Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
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/*
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* Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, version 2.
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*
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* Authors:
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* Casey Schaufler <casey@schaufler-ca.com>
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* Ahmed S. Darwish <darwish.07@gmail.com>
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*
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* Special thanks to the authors of selinuxfs.
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*
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* Karl MacMillan <kmacmillan@tresys.com>
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* James Morris <jmorris@redhat.com>
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*
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*/
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#include <linux/kernel.h>
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#include <linux/vmalloc.h>
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#include <linux/security.h>
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#include <linux/mutex.h>
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2009-01-01 01:54:12 +08:00
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#include <net/net_namespace.h>
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Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
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#include <net/netlabel.h>
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#include <net/cipso_ipv4.h>
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#include <linux/seq_file.h>
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#include <linux/ctype.h>
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2008-02-16 07:24:25 +08:00
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#include <linux/audit.h>
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Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
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|
#include "smack.h"
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|
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/*
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* smackfs pseudo filesystem.
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*/
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enum smk_inos {
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SMK_ROOT_INO = 2,
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SMK_LOAD = 3, /* load policy */
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SMK_CIPSO = 4, /* load label -> CIPSO mapping */
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SMK_DOI = 5, /* CIPSO DOI */
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SMK_DIRECT = 6, /* CIPSO level indicating direct label */
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SMK_AMBIENT = 7, /* internet ambient label */
|
2009-01-01 01:54:12 +08:00
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SMK_NETLBLADDR = 8, /* single label hosts */
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2008-07-31 06:37:11 +08:00
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SMK_ONLYCAP = 9, /* the only "capable" label */
|
2009-04-09 02:40:06 +08:00
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SMK_LOGGING = 10, /* logging */
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
};
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/*
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* List locks
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*/
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static DEFINE_MUTEX(smack_list_lock);
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static DEFINE_MUTEX(smack_cipso_lock);
|
2008-02-16 07:24:25 +08:00
|
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|
static DEFINE_MUTEX(smack_ambient_lock);
|
2009-01-01 01:54:12 +08:00
|
|
|
static DEFINE_MUTEX(smk_netlbladdr_lock);
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
|
|
|
/*
|
|
|
|
* This is the "ambient" label for network traffic.
|
|
|
|
* If it isn't somehow marked, use this.
|
|
|
|
* It can be reset via smackfs/ambient
|
|
|
|
*/
|
|
|
|
char *smack_net_ambient = smack_known_floor.smk_known;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* This is the level in a CIPSO header that indicates a
|
|
|
|
* smack label is contained directly in the category set.
|
|
|
|
* It can be reset via smackfs/direct
|
|
|
|
*/
|
|
|
|
int smack_cipso_direct = SMACK_CIPSO_DIRECT_DEFAULT;
|
|
|
|
|
2008-07-31 06:37:11 +08:00
|
|
|
/*
|
|
|
|
* Unless a process is running with this label even
|
|
|
|
* having CAP_MAC_OVERRIDE isn't enough to grant
|
|
|
|
* privilege to violate MAC policy. If no label is
|
|
|
|
* designated (the NULL case) capabilities apply to
|
|
|
|
* everyone. It is expected that the hat (^) label
|
|
|
|
* will be used if any label is used.
|
|
|
|
*/
|
|
|
|
char *smack_onlycap;
|
|
|
|
|
2009-01-01 01:54:12 +08:00
|
|
|
/*
|
|
|
|
* Certain IP addresses may be designated as single label hosts.
|
|
|
|
* Packets are sent there unlabeled, but only from tasks that
|
|
|
|
* can write to the specified label.
|
|
|
|
*/
|
2009-03-25 03:53:24 +08:00
|
|
|
|
|
|
|
LIST_HEAD(smk_netlbladdr_list);
|
|
|
|
LIST_HEAD(smack_rule_list);
|
2009-01-01 01:54:12 +08:00
|
|
|
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
static int smk_cipso_doi_value = SMACK_CIPSO_DOI_DEFAULT;
|
|
|
|
|
2009-03-28 05:11:01 +08:00
|
|
|
const char *smack_cipso_option = SMACK_CIPSO_OPTION;
|
|
|
|
|
|
|
|
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
#define SEQ_READ_FINISHED 1
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Values for parsing cipso rules
|
|
|
|
* SMK_DIGITLEN: Length of a digit field in a rule.
|
2008-03-14 03:32:34 +08:00
|
|
|
* SMK_CIPSOMIN: Minimum possible cipso rule length.
|
|
|
|
* SMK_CIPSOMAX: Maximum possible cipso rule length.
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
*/
|
|
|
|
#define SMK_DIGITLEN 4
|
2008-03-14 03:32:34 +08:00
|
|
|
#define SMK_CIPSOMIN (SMK_LABELLEN + 2 * SMK_DIGITLEN)
|
|
|
|
#define SMK_CIPSOMAX (SMK_CIPSOMIN + SMACK_CIPSO_MAXCATNUM * SMK_DIGITLEN)
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Values for parsing MAC rules
|
|
|
|
* SMK_ACCESS: Maximum possible combination of access permissions
|
|
|
|
* SMK_ACCESSLEN: Maximum length for a rule access field
|
|
|
|
* SMK_LOADLEN: Smack rule length
|
|
|
|
*/
|
|
|
|
#define SMK_ACCESS "rwxa"
|
|
|
|
#define SMK_ACCESSLEN (sizeof(SMK_ACCESS) - 1)
|
|
|
|
#define SMK_LOADLEN (SMK_LABELLEN + SMK_LABELLEN + SMK_ACCESSLEN)
|
|
|
|
|
2009-01-01 01:54:12 +08:00
|
|
|
/**
|
|
|
|
* smk_netlabel_audit_set - fill a netlbl_audit struct
|
|
|
|
* @nap: structure to fill
|
|
|
|
*/
|
|
|
|
static void smk_netlabel_audit_set(struct netlbl_audit *nap)
|
|
|
|
{
|
|
|
|
nap->loginuid = audit_get_loginuid(current);
|
|
|
|
nap->sessionid = audit_get_sessionid(current);
|
|
|
|
nap->secid = smack_to_secid(current_security());
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Values for parsing single label host rules
|
|
|
|
* "1.2.3.4 X"
|
|
|
|
* "192.168.138.129/32 abcdefghijklmnopqrstuvw"
|
|
|
|
*/
|
|
|
|
#define SMK_NETLBLADDRMIN 9
|
|
|
|
#define SMK_NETLBLADDRMAX 42
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
|
|
|
/*
|
|
|
|
* Seq_file read operations for /smack/load
|
|
|
|
*/
|
|
|
|
|
|
|
|
static void *load_seq_start(struct seq_file *s, loff_t *pos)
|
|
|
|
{
|
|
|
|
if (*pos == SEQ_READ_FINISHED)
|
|
|
|
return NULL;
|
2009-03-25 03:53:24 +08:00
|
|
|
if (list_empty(&smack_rule_list))
|
|
|
|
return NULL;
|
|
|
|
return smack_rule_list.next;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
static void *load_seq_next(struct seq_file *s, void *v, loff_t *pos)
|
|
|
|
{
|
2009-03-25 03:53:24 +08:00
|
|
|
struct list_head *list = v;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
2009-03-25 03:53:24 +08:00
|
|
|
if (list_is_last(list, &smack_rule_list)) {
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
*pos = SEQ_READ_FINISHED;
|
2009-03-25 03:53:24 +08:00
|
|
|
return NULL;
|
|
|
|
}
|
|
|
|
return list->next;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
static int load_seq_show(struct seq_file *s, void *v)
|
|
|
|
{
|
2009-03-25 03:53:24 +08:00
|
|
|
struct list_head *list = v;
|
|
|
|
struct smack_rule *srp =
|
|
|
|
list_entry(list, struct smack_rule, list);
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
|
|
|
seq_printf(s, "%s %s", (char *)srp->smk_subject,
|
|
|
|
(char *)srp->smk_object);
|
|
|
|
|
|
|
|
seq_putc(s, ' ');
|
|
|
|
|
|
|
|
if (srp->smk_access & MAY_READ)
|
|
|
|
seq_putc(s, 'r');
|
|
|
|
if (srp->smk_access & MAY_WRITE)
|
|
|
|
seq_putc(s, 'w');
|
|
|
|
if (srp->smk_access & MAY_EXEC)
|
|
|
|
seq_putc(s, 'x');
|
|
|
|
if (srp->smk_access & MAY_APPEND)
|
|
|
|
seq_putc(s, 'a');
|
|
|
|
if (srp->smk_access == 0)
|
|
|
|
seq_putc(s, '-');
|
|
|
|
|
|
|
|
seq_putc(s, '\n');
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void load_seq_stop(struct seq_file *s, void *v)
|
|
|
|
{
|
|
|
|
/* No-op */
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct seq_operations load_seq_ops = {
|
|
|
|
.start = load_seq_start,
|
|
|
|
.next = load_seq_next,
|
|
|
|
.show = load_seq_show,
|
|
|
|
.stop = load_seq_stop,
|
|
|
|
};
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_open_load - open() for /smack/load
|
|
|
|
* @inode: inode structure representing file
|
|
|
|
* @file: "load" file pointer
|
|
|
|
*
|
|
|
|
* For reading, use load_seq_* seq_file reading operations.
|
|
|
|
*/
|
|
|
|
static int smk_open_load(struct inode *inode, struct file *file)
|
|
|
|
{
|
2008-03-25 03:29:49 +08:00
|
|
|
return seq_open(file, &load_seq_ops);
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_set_access - add a rule to the rule list
|
|
|
|
* @srp: the new rule to add
|
|
|
|
*
|
|
|
|
* Looks through the current subject/object/access list for
|
|
|
|
* the subject/object pair and replaces the access that was
|
|
|
|
* there. If the pair isn't found add it with the specified
|
|
|
|
* access.
|
2008-12-22 12:16:15 +08:00
|
|
|
*
|
|
|
|
* Returns 0 if nothing goes wrong or -ENOMEM if it fails
|
|
|
|
* during the allocation of the new pair to add.
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
*/
|
2008-12-22 12:16:15 +08:00
|
|
|
static int smk_set_access(struct smack_rule *srp)
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
{
|
2009-03-25 03:53:24 +08:00
|
|
|
struct smack_rule *sp;
|
2008-12-22 12:16:15 +08:00
|
|
|
int ret = 0;
|
2009-03-25 03:53:24 +08:00
|
|
|
int found;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
mutex_lock(&smack_list_lock);
|
|
|
|
|
2009-03-25 03:53:24 +08:00
|
|
|
found = 0;
|
|
|
|
list_for_each_entry_rcu(sp, &smack_rule_list, list) {
|
|
|
|
if (sp->smk_subject == srp->smk_subject &&
|
|
|
|
sp->smk_object == srp->smk_object) {
|
|
|
|
found = 1;
|
|
|
|
sp->smk_access = srp->smk_access;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
2009-03-25 03:53:24 +08:00
|
|
|
if (found == 0)
|
|
|
|
list_add_rcu(&srp->list, &smack_rule_list);
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
|
|
|
mutex_unlock(&smack_list_lock);
|
|
|
|
|
2008-12-22 12:16:15 +08:00
|
|
|
return ret;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_write_load - write() for /smack/load
|
2009-02-19 03:42:33 +08:00
|
|
|
* @file: file pointer, not actually used
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
* @buf: where to get the data from
|
|
|
|
* @count: bytes sent
|
|
|
|
* @ppos: where to start - must be 0
|
|
|
|
*
|
|
|
|
* Get one smack access rule from above.
|
|
|
|
* The format is exactly:
|
|
|
|
* char subject[SMK_LABELLEN]
|
|
|
|
* char object[SMK_LABELLEN]
|
2008-03-14 03:32:34 +08:00
|
|
|
* char access[SMK_ACCESSLEN]
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
*
|
2008-03-14 03:32:34 +08:00
|
|
|
* writes must be SMK_LABELLEN+SMK_LABELLEN+SMK_ACCESSLEN bytes.
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
*/
|
|
|
|
static ssize_t smk_write_load(struct file *file, const char __user *buf,
|
|
|
|
size_t count, loff_t *ppos)
|
|
|
|
{
|
2009-03-25 03:53:24 +08:00
|
|
|
struct smack_rule *rule;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
char *data;
|
|
|
|
int rc = -EINVAL;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Must have privilege.
|
|
|
|
* No partial writes.
|
|
|
|
* Enough data must be present.
|
|
|
|
*/
|
|
|
|
if (!capable(CAP_MAC_ADMIN))
|
|
|
|
return -EPERM;
|
2009-03-25 03:53:24 +08:00
|
|
|
|
|
|
|
if (*ppos != 0 || count != SMK_LOADLEN)
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
data = kzalloc(count, GFP_KERNEL);
|
|
|
|
if (data == NULL)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
if (copy_from_user(data, buf, count) != 0) {
|
|
|
|
rc = -EFAULT;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
2009-03-25 03:53:24 +08:00
|
|
|
rule = kzalloc(sizeof(*rule), GFP_KERNEL);
|
|
|
|
if (rule == NULL) {
|
|
|
|
rc = -ENOMEM;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
goto out;
|
2009-03-25 03:53:24 +08:00
|
|
|
}
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
2009-03-25 03:53:24 +08:00
|
|
|
rule->smk_subject = smk_import(data, 0);
|
|
|
|
if (rule->smk_subject == NULL)
|
|
|
|
goto out_free_rule;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
2009-03-25 03:53:24 +08:00
|
|
|
rule->smk_object = smk_import(data + SMK_LABELLEN, 0);
|
|
|
|
if (rule->smk_object == NULL)
|
|
|
|
goto out_free_rule;
|
|
|
|
|
|
|
|
rule->smk_access = 0;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
|
|
|
switch (data[SMK_LABELLEN + SMK_LABELLEN]) {
|
|
|
|
case '-':
|
|
|
|
break;
|
|
|
|
case 'r':
|
|
|
|
case 'R':
|
2009-03-25 03:53:24 +08:00
|
|
|
rule->smk_access |= MAY_READ;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
break;
|
|
|
|
default:
|
2009-03-25 03:53:24 +08:00
|
|
|
goto out_free_rule;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
switch (data[SMK_LABELLEN + SMK_LABELLEN + 1]) {
|
|
|
|
case '-':
|
|
|
|
break;
|
|
|
|
case 'w':
|
|
|
|
case 'W':
|
2009-03-25 03:53:24 +08:00
|
|
|
rule->smk_access |= MAY_WRITE;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
break;
|
|
|
|
default:
|
2009-03-25 03:53:24 +08:00
|
|
|
goto out_free_rule;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
switch (data[SMK_LABELLEN + SMK_LABELLEN + 2]) {
|
|
|
|
case '-':
|
|
|
|
break;
|
|
|
|
case 'x':
|
|
|
|
case 'X':
|
2009-03-25 03:53:24 +08:00
|
|
|
rule->smk_access |= MAY_EXEC;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
break;
|
|
|
|
default:
|
2009-03-25 03:53:24 +08:00
|
|
|
goto out_free_rule;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
switch (data[SMK_LABELLEN + SMK_LABELLEN + 3]) {
|
|
|
|
case '-':
|
|
|
|
break;
|
|
|
|
case 'a':
|
|
|
|
case 'A':
|
2009-03-25 03:53:24 +08:00
|
|
|
rule->smk_access |= MAY_APPEND;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
break;
|
|
|
|
default:
|
2009-03-25 03:53:24 +08:00
|
|
|
goto out_free_rule;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
}
|
|
|
|
|
2009-03-25 03:53:24 +08:00
|
|
|
rc = smk_set_access(rule);
|
2008-12-22 12:16:15 +08:00
|
|
|
|
|
|
|
if (!rc)
|
|
|
|
rc = count;
|
2009-03-25 03:53:24 +08:00
|
|
|
goto out;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
2009-03-25 03:53:24 +08:00
|
|
|
out_free_rule:
|
|
|
|
kfree(rule);
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
out:
|
|
|
|
kfree(data);
|
|
|
|
return rc;
|
|
|
|
}
|
|
|
|
|
|
|
|
static const struct file_operations smk_load_ops = {
|
|
|
|
.open = smk_open_load,
|
|
|
|
.read = seq_read,
|
|
|
|
.llseek = seq_lseek,
|
|
|
|
.write = smk_write_load,
|
2008-03-25 03:29:49 +08:00
|
|
|
.release = seq_release,
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
};
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_cipso_doi - initialize the CIPSO domain
|
|
|
|
*/
|
2008-04-28 17:13:43 +08:00
|
|
|
static void smk_cipso_doi(void)
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
{
|
|
|
|
int rc;
|
|
|
|
struct cipso_v4_doi *doip;
|
2009-01-01 01:54:12 +08:00
|
|
|
struct netlbl_audit nai;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
2009-01-01 01:54:12 +08:00
|
|
|
smk_netlabel_audit_set(&nai);
|
2008-02-16 07:24:25 +08:00
|
|
|
|
2009-01-01 01:54:12 +08:00
|
|
|
rc = netlbl_cfg_map_del(NULL, PF_INET, NULL, NULL, &nai);
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
if (rc != 0)
|
|
|
|
printk(KERN_WARNING "%s:%d remove rc = %d\n",
|
|
|
|
__func__, __LINE__, rc);
|
|
|
|
|
|
|
|
doip = kmalloc(sizeof(struct cipso_v4_doi), GFP_KERNEL);
|
|
|
|
if (doip == NULL)
|
|
|
|
panic("smack: Failed to initialize cipso DOI.\n");
|
|
|
|
doip->map.std = NULL;
|
|
|
|
doip->doi = smk_cipso_doi_value;
|
|
|
|
doip->type = CIPSO_V4_MAP_PASS;
|
|
|
|
doip->tags[0] = CIPSO_V4_TAG_RBITMAP;
|
|
|
|
for (rc = 1; rc < CIPSO_V4_TAG_MAXCNT; rc++)
|
|
|
|
doip->tags[rc] = CIPSO_V4_TAG_INVALID;
|
|
|
|
|
2009-01-01 01:54:12 +08:00
|
|
|
rc = netlbl_cfg_cipsov4_add(doip, &nai);
|
2008-10-10 22:16:31 +08:00
|
|
|
if (rc != 0) {
|
2009-01-01 01:54:11 +08:00
|
|
|
printk(KERN_WARNING "%s:%d cipso add rc = %d\n",
|
|
|
|
__func__, __LINE__, rc);
|
|
|
|
kfree(doip);
|
|
|
|
return;
|
|
|
|
}
|
2009-01-01 01:54:12 +08:00
|
|
|
rc = netlbl_cfg_cipsov4_map_add(doip->doi, NULL, NULL, NULL, &nai);
|
2009-01-01 01:54:11 +08:00
|
|
|
if (rc != 0) {
|
|
|
|
printk(KERN_WARNING "%s:%d map add rc = %d\n",
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
__func__, __LINE__, rc);
|
2008-10-10 22:16:31 +08:00
|
|
|
kfree(doip);
|
2009-01-01 01:54:11 +08:00
|
|
|
return;
|
2008-10-10 22:16:31 +08:00
|
|
|
}
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
}
|
|
|
|
|
2008-02-16 07:24:25 +08:00
|
|
|
/**
|
|
|
|
* smk_unlbl_ambient - initialize the unlabeled domain
|
2009-02-19 03:42:33 +08:00
|
|
|
* @oldambient: previous domain string
|
2008-02-16 07:24:25 +08:00
|
|
|
*/
|
2008-04-28 17:13:43 +08:00
|
|
|
static void smk_unlbl_ambient(char *oldambient)
|
2008-02-16 07:24:25 +08:00
|
|
|
{
|
|
|
|
int rc;
|
2009-01-01 01:54:12 +08:00
|
|
|
struct netlbl_audit nai;
|
2008-02-16 07:24:25 +08:00
|
|
|
|
2009-01-01 01:54:12 +08:00
|
|
|
smk_netlabel_audit_set(&nai);
|
2008-02-16 07:24:25 +08:00
|
|
|
|
|
|
|
if (oldambient != NULL) {
|
2009-01-01 01:54:12 +08:00
|
|
|
rc = netlbl_cfg_map_del(oldambient, PF_INET, NULL, NULL, &nai);
|
2008-02-16 07:24:25 +08:00
|
|
|
if (rc != 0)
|
|
|
|
printk(KERN_WARNING "%s:%d remove rc = %d\n",
|
|
|
|
__func__, __LINE__, rc);
|
|
|
|
}
|
|
|
|
|
2009-01-01 01:54:12 +08:00
|
|
|
rc = netlbl_cfg_unlbl_map_add(smack_net_ambient, PF_INET,
|
|
|
|
NULL, NULL, &nai);
|
2008-02-16 07:24:25 +08:00
|
|
|
if (rc != 0)
|
|
|
|
printk(KERN_WARNING "%s:%d add rc = %d\n",
|
|
|
|
__func__, __LINE__, rc);
|
|
|
|
}
|
|
|
|
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
/*
|
|
|
|
* Seq_file read operations for /smack/cipso
|
|
|
|
*/
|
|
|
|
|
|
|
|
static void *cipso_seq_start(struct seq_file *s, loff_t *pos)
|
|
|
|
{
|
|
|
|
if (*pos == SEQ_READ_FINISHED)
|
|
|
|
return NULL;
|
2009-03-25 03:53:24 +08:00
|
|
|
if (list_empty(&smack_known_list))
|
|
|
|
return NULL;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
2009-03-25 03:53:24 +08:00
|
|
|
return smack_known_list.next;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
static void *cipso_seq_next(struct seq_file *s, void *v, loff_t *pos)
|
|
|
|
{
|
2009-03-25 03:53:24 +08:00
|
|
|
struct list_head *list = v;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
|
|
|
/*
|
2009-03-25 03:53:24 +08:00
|
|
|
* labels with no associated cipso value wont be printed
|
|
|
|
* in cipso_seq_show
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
*/
|
2009-03-25 03:53:24 +08:00
|
|
|
if (list_is_last(list, &smack_known_list)) {
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
*pos = SEQ_READ_FINISHED;
|
2009-03-25 03:53:24 +08:00
|
|
|
return NULL;
|
|
|
|
}
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
2009-03-25 03:53:24 +08:00
|
|
|
return list->next;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Print cipso labels in format:
|
|
|
|
* label level[/cat[,cat]]
|
|
|
|
*/
|
|
|
|
static int cipso_seq_show(struct seq_file *s, void *v)
|
|
|
|
{
|
2009-03-25 03:53:24 +08:00
|
|
|
struct list_head *list = v;
|
|
|
|
struct smack_known *skp =
|
|
|
|
list_entry(list, struct smack_known, list);
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
struct smack_cipso *scp = skp->smk_cipso;
|
|
|
|
char *cbp;
|
|
|
|
char sep = '/';
|
|
|
|
int cat = 1;
|
|
|
|
int i;
|
|
|
|
unsigned char m;
|
|
|
|
|
|
|
|
if (scp == NULL)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
seq_printf(s, "%s %3d", (char *)&skp->smk_known, scp->smk_level);
|
|
|
|
|
|
|
|
cbp = scp->smk_catset;
|
|
|
|
for (i = 0; i < SMK_LABELLEN; i++)
|
|
|
|
for (m = 0x80; m != 0; m >>= 1) {
|
|
|
|
if (m & cbp[i]) {
|
|
|
|
seq_printf(s, "%c%d", sep, cat);
|
|
|
|
sep = ',';
|
|
|
|
}
|
|
|
|
cat++;
|
|
|
|
}
|
|
|
|
|
|
|
|
seq_putc(s, '\n');
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void cipso_seq_stop(struct seq_file *s, void *v)
|
|
|
|
{
|
|
|
|
/* No-op */
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct seq_operations cipso_seq_ops = {
|
|
|
|
.start = cipso_seq_start,
|
|
|
|
.stop = cipso_seq_stop,
|
|
|
|
.next = cipso_seq_next,
|
|
|
|
.show = cipso_seq_show,
|
|
|
|
};
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_open_cipso - open() for /smack/cipso
|
|
|
|
* @inode: inode structure representing file
|
|
|
|
* @file: "cipso" file pointer
|
|
|
|
*
|
|
|
|
* Connect our cipso_seq_* operations with /smack/cipso
|
|
|
|
* file_operations
|
|
|
|
*/
|
|
|
|
static int smk_open_cipso(struct inode *inode, struct file *file)
|
|
|
|
{
|
|
|
|
return seq_open(file, &cipso_seq_ops);
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_write_cipso - write() for /smack/cipso
|
2009-02-19 03:42:33 +08:00
|
|
|
* @file: file pointer, not actually used
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
* @buf: where to get the data from
|
|
|
|
* @count: bytes sent
|
|
|
|
* @ppos: where to start
|
|
|
|
*
|
|
|
|
* Accepts only one cipso rule per write call.
|
|
|
|
* Returns number of bytes written or error code, as appropriate
|
|
|
|
*/
|
|
|
|
static ssize_t smk_write_cipso(struct file *file, const char __user *buf,
|
|
|
|
size_t count, loff_t *ppos)
|
|
|
|
{
|
|
|
|
struct smack_known *skp;
|
|
|
|
struct smack_cipso *scp = NULL;
|
|
|
|
char mapcatset[SMK_LABELLEN];
|
|
|
|
int maplevel;
|
|
|
|
int cat;
|
|
|
|
int catlen;
|
|
|
|
ssize_t rc = -EINVAL;
|
|
|
|
char *data = NULL;
|
|
|
|
char *rule;
|
|
|
|
int ret;
|
|
|
|
int i;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Must have privilege.
|
|
|
|
* No partial writes.
|
|
|
|
* Enough data must be present.
|
|
|
|
*/
|
|
|
|
if (!capable(CAP_MAC_ADMIN))
|
|
|
|
return -EPERM;
|
|
|
|
if (*ppos != 0)
|
|
|
|
return -EINVAL;
|
2008-03-14 03:32:34 +08:00
|
|
|
if (count < SMK_CIPSOMIN || count > SMK_CIPSOMAX)
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
data = kzalloc(count + 1, GFP_KERNEL);
|
|
|
|
if (data == NULL)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
if (copy_from_user(data, buf, count) != 0) {
|
|
|
|
rc = -EFAULT;
|
|
|
|
goto unlockedout;
|
|
|
|
}
|
|
|
|
|
2009-03-28 05:11:01 +08:00
|
|
|
/* labels cannot begin with a '-' */
|
|
|
|
if (data[0] == '-') {
|
|
|
|
rc = -EINVAL;
|
|
|
|
goto unlockedout;
|
|
|
|
}
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
data[count] = '\0';
|
|
|
|
rule = data;
|
|
|
|
/*
|
|
|
|
* Only allow one writer at a time. Writes should be
|
|
|
|
* quite rare and small in any case.
|
|
|
|
*/
|
|
|
|
mutex_lock(&smack_cipso_lock);
|
|
|
|
|
|
|
|
skp = smk_import_entry(rule, 0);
|
|
|
|
if (skp == NULL)
|
|
|
|
goto out;
|
|
|
|
|
2009-01-08 10:09:08 +08:00
|
|
|
rule += SMK_LABELLEN;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
ret = sscanf(rule, "%d", &maplevel);
|
|
|
|
if (ret != 1 || maplevel > SMACK_CIPSO_MAXLEVEL)
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
rule += SMK_DIGITLEN;
|
|
|
|
ret = sscanf(rule, "%d", &catlen);
|
|
|
|
if (ret != 1 || catlen > SMACK_CIPSO_MAXCATNUM)
|
|
|
|
goto out;
|
|
|
|
|
2008-03-14 03:32:34 +08:00
|
|
|
if (count != (SMK_CIPSOMIN + catlen * SMK_DIGITLEN))
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
goto out;
|
|
|
|
|
|
|
|
memset(mapcatset, 0, sizeof(mapcatset));
|
|
|
|
|
|
|
|
for (i = 0; i < catlen; i++) {
|
|
|
|
rule += SMK_DIGITLEN;
|
|
|
|
ret = sscanf(rule, "%d", &cat);
|
|
|
|
if (ret != 1 || cat > SMACK_CIPSO_MAXCATVAL)
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
smack_catset_bit(cat, mapcatset);
|
|
|
|
}
|
|
|
|
|
|
|
|
if (skp->smk_cipso == NULL) {
|
|
|
|
scp = kzalloc(sizeof(struct smack_cipso), GFP_KERNEL);
|
|
|
|
if (scp == NULL) {
|
|
|
|
rc = -ENOMEM;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
spin_lock_bh(&skp->smk_cipsolock);
|
|
|
|
|
|
|
|
if (scp == NULL)
|
|
|
|
scp = skp->smk_cipso;
|
|
|
|
else
|
|
|
|
skp->smk_cipso = scp;
|
|
|
|
|
|
|
|
scp->smk_level = maplevel;
|
|
|
|
memcpy(scp->smk_catset, mapcatset, sizeof(mapcatset));
|
|
|
|
|
|
|
|
spin_unlock_bh(&skp->smk_cipsolock);
|
|
|
|
|
|
|
|
rc = count;
|
|
|
|
out:
|
|
|
|
mutex_unlock(&smack_cipso_lock);
|
|
|
|
unlockedout:
|
|
|
|
kfree(data);
|
|
|
|
return rc;
|
|
|
|
}
|
|
|
|
|
|
|
|
static const struct file_operations smk_cipso_ops = {
|
|
|
|
.open = smk_open_cipso,
|
|
|
|
.read = seq_read,
|
|
|
|
.llseek = seq_lseek,
|
|
|
|
.write = smk_write_cipso,
|
|
|
|
.release = seq_release,
|
|
|
|
};
|
|
|
|
|
2009-01-01 01:54:12 +08:00
|
|
|
/*
|
|
|
|
* Seq_file read operations for /smack/netlabel
|
|
|
|
*/
|
|
|
|
|
|
|
|
static void *netlbladdr_seq_start(struct seq_file *s, loff_t *pos)
|
|
|
|
{
|
|
|
|
if (*pos == SEQ_READ_FINISHED)
|
|
|
|
return NULL;
|
2009-03-25 03:53:24 +08:00
|
|
|
if (list_empty(&smk_netlbladdr_list))
|
|
|
|
return NULL;
|
|
|
|
return smk_netlbladdr_list.next;
|
2009-01-01 01:54:12 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
static void *netlbladdr_seq_next(struct seq_file *s, void *v, loff_t *pos)
|
|
|
|
{
|
2009-03-25 03:53:24 +08:00
|
|
|
struct list_head *list = v;
|
2009-01-01 01:54:12 +08:00
|
|
|
|
2009-03-25 03:53:24 +08:00
|
|
|
if (list_is_last(list, &smk_netlbladdr_list)) {
|
2009-01-01 01:54:12 +08:00
|
|
|
*pos = SEQ_READ_FINISHED;
|
2009-03-25 03:53:24 +08:00
|
|
|
return NULL;
|
|
|
|
}
|
2009-01-01 01:54:12 +08:00
|
|
|
|
2009-03-25 03:53:24 +08:00
|
|
|
return list->next;
|
2009-01-01 01:54:12 +08:00
|
|
|
}
|
|
|
|
#define BEBITS (sizeof(__be32) * 8)
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Print host/label pairs
|
|
|
|
*/
|
|
|
|
static int netlbladdr_seq_show(struct seq_file *s, void *v)
|
|
|
|
{
|
2009-03-25 03:53:24 +08:00
|
|
|
struct list_head *list = v;
|
|
|
|
struct smk_netlbladdr *skp =
|
|
|
|
list_entry(list, struct smk_netlbladdr, list);
|
2009-01-01 01:54:12 +08:00
|
|
|
unsigned char *hp = (char *) &skp->smk_host.sin_addr.s_addr;
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
int maskn;
|
|
|
|
u32 temp_mask = be32_to_cpu(skp->smk_mask.s_addr);
|
2009-01-01 01:54:12 +08:00
|
|
|
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
for (maskn = 0; temp_mask; temp_mask <<= 1, maskn++);
|
2009-01-01 01:54:12 +08:00
|
|
|
|
|
|
|
seq_printf(s, "%u.%u.%u.%u/%d %s\n",
|
|
|
|
hp[0], hp[1], hp[2], hp[3], maskn, skp->smk_label);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void netlbladdr_seq_stop(struct seq_file *s, void *v)
|
|
|
|
{
|
|
|
|
/* No-op */
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct seq_operations netlbladdr_seq_ops = {
|
|
|
|
.start = netlbladdr_seq_start,
|
|
|
|
.stop = netlbladdr_seq_stop,
|
|
|
|
.next = netlbladdr_seq_next,
|
|
|
|
.show = netlbladdr_seq_show,
|
|
|
|
};
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_open_netlbladdr - open() for /smack/netlabel
|
|
|
|
* @inode: inode structure representing file
|
|
|
|
* @file: "netlabel" file pointer
|
|
|
|
*
|
|
|
|
* Connect our netlbladdr_seq_* operations with /smack/netlabel
|
|
|
|
* file_operations
|
|
|
|
*/
|
|
|
|
static int smk_open_netlbladdr(struct inode *inode, struct file *file)
|
|
|
|
{
|
|
|
|
return seq_open(file, &netlbladdr_seq_ops);
|
|
|
|
}
|
|
|
|
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
/**
|
|
|
|
* smk_netlbladdr_insert
|
|
|
|
* @new : netlabel to insert
|
|
|
|
*
|
|
|
|
* This helper insert netlabel in the smack_netlbladdrs list
|
|
|
|
* sorted by netmask length (longest to smallest)
|
2009-03-25 03:53:24 +08:00
|
|
|
* locked by &smk_netlbladdr_lock in smk_write_netlbladdr
|
|
|
|
*
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
*/
|
|
|
|
static void smk_netlbladdr_insert(struct smk_netlbladdr *new)
|
|
|
|
{
|
2009-03-25 03:53:24 +08:00
|
|
|
struct smk_netlbladdr *m, *m_next;
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
|
2009-03-25 03:53:24 +08:00
|
|
|
if (list_empty(&smk_netlbladdr_list)) {
|
|
|
|
list_add_rcu(&new->list, &smk_netlbladdr_list);
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
2009-04-15 02:17:16 +08:00
|
|
|
m = list_entry_rcu(smk_netlbladdr_list.next,
|
|
|
|
struct smk_netlbladdr, list);
|
2009-03-25 03:53:24 +08:00
|
|
|
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
/* the comparison '>' is a bit hacky, but works */
|
2009-03-25 03:53:24 +08:00
|
|
|
if (new->smk_mask.s_addr > m->smk_mask.s_addr) {
|
|
|
|
list_add_rcu(&new->list, &smk_netlbladdr_list);
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
return;
|
|
|
|
}
|
2009-03-25 03:53:24 +08:00
|
|
|
|
|
|
|
list_for_each_entry_rcu(m, &smk_netlbladdr_list, list) {
|
|
|
|
if (list_is_last(&m->list, &smk_netlbladdr_list)) {
|
|
|
|
list_add_rcu(&new->list, &m->list);
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
return;
|
|
|
|
}
|
2009-04-15 02:17:16 +08:00
|
|
|
m_next = list_entry_rcu(m->list.next,
|
|
|
|
struct smk_netlbladdr, list);
|
2009-03-25 03:53:24 +08:00
|
|
|
if (new->smk_mask.s_addr > m_next->smk_mask.s_addr) {
|
|
|
|
list_add_rcu(&new->list, &m->list);
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
return;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
|
2009-01-01 01:54:12 +08:00
|
|
|
/**
|
|
|
|
* smk_write_netlbladdr - write() for /smack/netlabel
|
2009-02-19 03:42:33 +08:00
|
|
|
* @file: file pointer, not actually used
|
2009-01-01 01:54:12 +08:00
|
|
|
* @buf: where to get the data from
|
|
|
|
* @count: bytes sent
|
|
|
|
* @ppos: where to start
|
|
|
|
*
|
|
|
|
* Accepts only one netlbladdr per write call.
|
|
|
|
* Returns number of bytes written or error code, as appropriate
|
|
|
|
*/
|
|
|
|
static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf,
|
|
|
|
size_t count, loff_t *ppos)
|
|
|
|
{
|
|
|
|
struct smk_netlbladdr *skp;
|
|
|
|
struct sockaddr_in newname;
|
|
|
|
char smack[SMK_LABELLEN];
|
|
|
|
char *sp;
|
2009-05-22 00:42:54 +08:00
|
|
|
char data[SMK_NETLBLADDRMAX + 1];
|
2009-01-01 01:54:12 +08:00
|
|
|
char *host = (char *)&newname.sin_addr.s_addr;
|
|
|
|
int rc;
|
|
|
|
struct netlbl_audit audit_info;
|
|
|
|
struct in_addr mask;
|
|
|
|
unsigned int m;
|
2009-03-25 03:53:24 +08:00
|
|
|
int found;
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
u32 mask_bits = (1<<31);
|
2009-01-01 01:54:12 +08:00
|
|
|
__be32 nsa;
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
u32 temp_mask;
|
2009-01-01 01:54:12 +08:00
|
|
|
|
|
|
|
/*
|
|
|
|
* Must have privilege.
|
|
|
|
* No partial writes.
|
|
|
|
* Enough data must be present.
|
|
|
|
* "<addr/mask, as a.b.c.d/e><space><label>"
|
|
|
|
* "<addr, as a.b.c.d><space><label>"
|
|
|
|
*/
|
|
|
|
if (!capable(CAP_MAC_ADMIN))
|
|
|
|
return -EPERM;
|
|
|
|
if (*ppos != 0)
|
|
|
|
return -EINVAL;
|
|
|
|
if (count < SMK_NETLBLADDRMIN || count > SMK_NETLBLADDRMAX)
|
|
|
|
return -EINVAL;
|
|
|
|
if (copy_from_user(data, buf, count) != 0)
|
|
|
|
return -EFAULT;
|
|
|
|
|
|
|
|
data[count] = '\0';
|
|
|
|
|
|
|
|
rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd/%d %s",
|
|
|
|
&host[0], &host[1], &host[2], &host[3], &m, smack);
|
|
|
|
if (rc != 6) {
|
|
|
|
rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd %s",
|
|
|
|
&host[0], &host[1], &host[2], &host[3], smack);
|
|
|
|
if (rc != 5)
|
|
|
|
return -EINVAL;
|
|
|
|
m = BEBITS;
|
|
|
|
}
|
|
|
|
if (m > BEBITS)
|
|
|
|
return -EINVAL;
|
|
|
|
|
2009-03-28 05:11:01 +08:00
|
|
|
/* if smack begins with '-', its an option, don't import it */
|
|
|
|
if (smack[0] != '-') {
|
|
|
|
sp = smk_import(smack, 0);
|
|
|
|
if (sp == NULL)
|
|
|
|
return -EINVAL;
|
|
|
|
} else {
|
|
|
|
/* check known options */
|
|
|
|
if (strcmp(smack, smack_cipso_option) == 0)
|
|
|
|
sp = (char *)smack_cipso_option;
|
|
|
|
else
|
|
|
|
return -EINVAL;
|
|
|
|
}
|
2009-01-01 01:54:12 +08:00
|
|
|
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
for (temp_mask = 0; m > 0; m--) {
|
|
|
|
temp_mask |= mask_bits;
|
|
|
|
mask_bits >>= 1;
|
2009-01-01 01:54:12 +08:00
|
|
|
}
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
mask.s_addr = cpu_to_be32(temp_mask);
|
|
|
|
|
|
|
|
newname.sin_addr.s_addr &= mask.s_addr;
|
2009-01-01 01:54:12 +08:00
|
|
|
/*
|
|
|
|
* Only allow one writer at a time. Writes should be
|
|
|
|
* quite rare and small in any case.
|
|
|
|
*/
|
|
|
|
mutex_lock(&smk_netlbladdr_lock);
|
|
|
|
|
|
|
|
nsa = newname.sin_addr.s_addr;
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
/* try to find if the prefix is already in the list */
|
2009-03-25 03:53:24 +08:00
|
|
|
found = 0;
|
|
|
|
list_for_each_entry_rcu(skp, &smk_netlbladdr_list, list) {
|
2009-01-01 01:54:12 +08:00
|
|
|
if (skp->smk_host.sin_addr.s_addr == nsa &&
|
2009-03-25 03:53:24 +08:00
|
|
|
skp->smk_mask.s_addr == mask.s_addr) {
|
|
|
|
found = 1;
|
2009-01-01 01:54:12 +08:00
|
|
|
break;
|
2009-03-25 03:53:24 +08:00
|
|
|
}
|
|
|
|
}
|
2009-01-01 01:54:12 +08:00
|
|
|
smk_netlabel_audit_set(&audit_info);
|
|
|
|
|
2009-03-25 03:53:24 +08:00
|
|
|
if (found == 0) {
|
2009-01-01 01:54:12 +08:00
|
|
|
skp = kzalloc(sizeof(*skp), GFP_KERNEL);
|
|
|
|
if (skp == NULL)
|
|
|
|
rc = -ENOMEM;
|
|
|
|
else {
|
|
|
|
rc = 0;
|
|
|
|
skp->smk_host.sin_addr.s_addr = newname.sin_addr.s_addr;
|
|
|
|
skp->smk_mask.s_addr = mask.s_addr;
|
|
|
|
skp->smk_label = sp;
|
smack: fixes for unlabeled host support
The following patch (against 2.6.29rc5) fixes a few issues in the
smack/netlabel "unlabeled host support" functionnality that was added in
2.6.29rc. It should go in before -final.
1) smack_host_label disregard a "0.0.0.0/0 @" rule (or other label),
preventing 'tagged' tasks to access Internet (many systems drop packets with
IP options)
2) netmasks were not handled correctly, they were stored in a way _not
equivalent_ to conversion to be32 (it was equivalent for /0, /8, /16, /24,
/32 masks but not other masks)
3) smack_netlbladdr prefixes (IP/mask) were not consistent (mask&IP was not
done), so there could have been different list entries for the same IP
prefix; if those entries had different labels, well ...
4) they were not sorted
1) 2) 3) are bugs, 4) is a more cosmetic issue.
The patch :
-creates a new helper smk_netlbladdr_insert to insert a smk_netlbladdr,
-sorted by netmask length
-use the new sorted nature of smack_netlbladdrs list to simplify
smack_host_label : the first match _will_ be the more specific
-corrects endianness issues in smk_write_netlbladdr & netlbladdr_seq_show
Signed-off-by: <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-03-04 14:33:51 +08:00
|
|
|
smk_netlbladdr_insert(skp);
|
2009-01-01 01:54:12 +08:00
|
|
|
}
|
|
|
|
} else {
|
2009-03-28 05:11:01 +08:00
|
|
|
/* we delete the unlabeled entry, only if the previous label
|
|
|
|
* wasnt the special CIPSO option */
|
|
|
|
if (skp->smk_label != smack_cipso_option)
|
|
|
|
rc = netlbl_cfg_unlbl_static_del(&init_net, NULL,
|
|
|
|
&skp->smk_host.sin_addr, &skp->smk_mask,
|
|
|
|
PF_INET, &audit_info);
|
|
|
|
else
|
|
|
|
rc = 0;
|
2009-01-01 01:54:12 +08:00
|
|
|
skp->smk_label = sp;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Now tell netlabel about the single label nature of
|
|
|
|
* this host so that incoming packets get labeled.
|
2009-03-28 05:11:01 +08:00
|
|
|
* but only if we didn't get the special CIPSO option
|
2009-01-01 01:54:12 +08:00
|
|
|
*/
|
2009-03-28 05:11:01 +08:00
|
|
|
if (rc == 0 && sp != smack_cipso_option)
|
2009-01-01 01:54:12 +08:00
|
|
|
rc = netlbl_cfg_unlbl_static_add(&init_net, NULL,
|
|
|
|
&skp->smk_host.sin_addr, &skp->smk_mask, PF_INET,
|
|
|
|
smack_to_secid(skp->smk_label), &audit_info);
|
|
|
|
|
|
|
|
if (rc == 0)
|
|
|
|
rc = count;
|
|
|
|
|
|
|
|
mutex_unlock(&smk_netlbladdr_lock);
|
|
|
|
|
|
|
|
return rc;
|
|
|
|
}
|
|
|
|
|
|
|
|
static const struct file_operations smk_netlbladdr_ops = {
|
|
|
|
.open = smk_open_netlbladdr,
|
|
|
|
.read = seq_read,
|
|
|
|
.llseek = seq_lseek,
|
|
|
|
.write = smk_write_netlbladdr,
|
|
|
|
.release = seq_release,
|
|
|
|
};
|
|
|
|
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
/**
|
|
|
|
* smk_read_doi - read() for /smack/doi
|
|
|
|
* @filp: file pointer, not actually used
|
|
|
|
* @buf: where to put the result
|
|
|
|
* @count: maximum to send along
|
|
|
|
* @ppos: where to start
|
|
|
|
*
|
|
|
|
* Returns number of bytes read or error code, as appropriate
|
|
|
|
*/
|
|
|
|
static ssize_t smk_read_doi(struct file *filp, char __user *buf,
|
|
|
|
size_t count, loff_t *ppos)
|
|
|
|
{
|
|
|
|
char temp[80];
|
|
|
|
ssize_t rc;
|
|
|
|
|
|
|
|
if (*ppos != 0)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
sprintf(temp, "%d", smk_cipso_doi_value);
|
|
|
|
rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
|
|
|
|
|
|
|
|
return rc;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_write_doi - write() for /smack/doi
|
2009-02-19 03:42:33 +08:00
|
|
|
* @file: file pointer, not actually used
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
* @buf: where to get the data from
|
|
|
|
* @count: bytes sent
|
|
|
|
* @ppos: where to start
|
|
|
|
*
|
|
|
|
* Returns number of bytes written or error code, as appropriate
|
|
|
|
*/
|
|
|
|
static ssize_t smk_write_doi(struct file *file, const char __user *buf,
|
|
|
|
size_t count, loff_t *ppos)
|
|
|
|
{
|
|
|
|
char temp[80];
|
|
|
|
int i;
|
|
|
|
|
|
|
|
if (!capable(CAP_MAC_ADMIN))
|
|
|
|
return -EPERM;
|
|
|
|
|
|
|
|
if (count >= sizeof(temp) || count == 0)
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
if (copy_from_user(temp, buf, count) != 0)
|
|
|
|
return -EFAULT;
|
|
|
|
|
|
|
|
temp[count] = '\0';
|
|
|
|
|
|
|
|
if (sscanf(temp, "%d", &i) != 1)
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
smk_cipso_doi_value = i;
|
|
|
|
|
|
|
|
smk_cipso_doi();
|
|
|
|
|
|
|
|
return count;
|
|
|
|
}
|
|
|
|
|
|
|
|
static const struct file_operations smk_doi_ops = {
|
|
|
|
.read = smk_read_doi,
|
|
|
|
.write = smk_write_doi,
|
|
|
|
};
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_read_direct - read() for /smack/direct
|
|
|
|
* @filp: file pointer, not actually used
|
|
|
|
* @buf: where to put the result
|
|
|
|
* @count: maximum to send along
|
|
|
|
* @ppos: where to start
|
|
|
|
*
|
|
|
|
* Returns number of bytes read or error code, as appropriate
|
|
|
|
*/
|
|
|
|
static ssize_t smk_read_direct(struct file *filp, char __user *buf,
|
|
|
|
size_t count, loff_t *ppos)
|
|
|
|
{
|
|
|
|
char temp[80];
|
|
|
|
ssize_t rc;
|
|
|
|
|
|
|
|
if (*ppos != 0)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
sprintf(temp, "%d", smack_cipso_direct);
|
|
|
|
rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
|
|
|
|
|
|
|
|
return rc;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_write_direct - write() for /smack/direct
|
2009-02-19 03:42:33 +08:00
|
|
|
* @file: file pointer, not actually used
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
* @buf: where to get the data from
|
|
|
|
* @count: bytes sent
|
|
|
|
* @ppos: where to start
|
|
|
|
*
|
|
|
|
* Returns number of bytes written or error code, as appropriate
|
|
|
|
*/
|
|
|
|
static ssize_t smk_write_direct(struct file *file, const char __user *buf,
|
|
|
|
size_t count, loff_t *ppos)
|
|
|
|
{
|
|
|
|
char temp[80];
|
|
|
|
int i;
|
|
|
|
|
|
|
|
if (!capable(CAP_MAC_ADMIN))
|
|
|
|
return -EPERM;
|
|
|
|
|
|
|
|
if (count >= sizeof(temp) || count == 0)
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
if (copy_from_user(temp, buf, count) != 0)
|
|
|
|
return -EFAULT;
|
|
|
|
|
|
|
|
temp[count] = '\0';
|
|
|
|
|
|
|
|
if (sscanf(temp, "%d", &i) != 1)
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
smack_cipso_direct = i;
|
|
|
|
|
|
|
|
return count;
|
|
|
|
}
|
|
|
|
|
|
|
|
static const struct file_operations smk_direct_ops = {
|
|
|
|
.read = smk_read_direct,
|
|
|
|
.write = smk_write_direct,
|
|
|
|
};
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_read_ambient - read() for /smack/ambient
|
|
|
|
* @filp: file pointer, not actually used
|
|
|
|
* @buf: where to put the result
|
|
|
|
* @cn: maximum to send along
|
|
|
|
* @ppos: where to start
|
|
|
|
*
|
|
|
|
* Returns number of bytes read or error code, as appropriate
|
|
|
|
*/
|
|
|
|
static ssize_t smk_read_ambient(struct file *filp, char __user *buf,
|
|
|
|
size_t cn, loff_t *ppos)
|
|
|
|
{
|
|
|
|
ssize_t rc;
|
|
|
|
int asize;
|
|
|
|
|
|
|
|
if (*ppos != 0)
|
|
|
|
return 0;
|
|
|
|
/*
|
|
|
|
* Being careful to avoid a problem in the case where
|
|
|
|
* smack_net_ambient gets changed in midstream.
|
|
|
|
*/
|
2008-02-16 07:24:25 +08:00
|
|
|
mutex_lock(&smack_ambient_lock);
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
2008-02-16 07:24:25 +08:00
|
|
|
asize = strlen(smack_net_ambient) + 1;
|
|
|
|
|
|
|
|
if (cn >= asize)
|
|
|
|
rc = simple_read_from_buffer(buf, cn, ppos,
|
|
|
|
smack_net_ambient, asize);
|
|
|
|
else
|
|
|
|
rc = -EINVAL;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
2008-02-16 07:24:25 +08:00
|
|
|
mutex_unlock(&smack_ambient_lock);
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
|
|
|
return rc;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_write_ambient - write() for /smack/ambient
|
2009-02-19 03:42:33 +08:00
|
|
|
* @file: file pointer, not actually used
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
* @buf: where to get the data from
|
|
|
|
* @count: bytes sent
|
|
|
|
* @ppos: where to start
|
|
|
|
*
|
|
|
|
* Returns number of bytes written or error code, as appropriate
|
|
|
|
*/
|
|
|
|
static ssize_t smk_write_ambient(struct file *file, const char __user *buf,
|
|
|
|
size_t count, loff_t *ppos)
|
|
|
|
{
|
|
|
|
char in[SMK_LABELLEN];
|
2008-02-16 07:24:25 +08:00
|
|
|
char *oldambient;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
char *smack;
|
|
|
|
|
|
|
|
if (!capable(CAP_MAC_ADMIN))
|
|
|
|
return -EPERM;
|
|
|
|
|
|
|
|
if (count >= SMK_LABELLEN)
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
if (copy_from_user(in, buf, count) != 0)
|
|
|
|
return -EFAULT;
|
|
|
|
|
|
|
|
smack = smk_import(in, count);
|
|
|
|
if (smack == NULL)
|
|
|
|
return -EINVAL;
|
|
|
|
|
2008-02-16 07:24:25 +08:00
|
|
|
mutex_lock(&smack_ambient_lock);
|
|
|
|
|
|
|
|
oldambient = smack_net_ambient;
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
smack_net_ambient = smack;
|
2008-02-16 07:24:25 +08:00
|
|
|
smk_unlbl_ambient(oldambient);
|
|
|
|
|
|
|
|
mutex_unlock(&smack_ambient_lock);
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
|
|
|
|
return count;
|
|
|
|
}
|
|
|
|
|
|
|
|
static const struct file_operations smk_ambient_ops = {
|
|
|
|
.read = smk_read_ambient,
|
|
|
|
.write = smk_write_ambient,
|
|
|
|
};
|
|
|
|
|
2008-07-31 06:37:11 +08:00
|
|
|
/**
|
|
|
|
* smk_read_onlycap - read() for /smack/onlycap
|
|
|
|
* @filp: file pointer, not actually used
|
|
|
|
* @buf: where to put the result
|
|
|
|
* @cn: maximum to send along
|
|
|
|
* @ppos: where to start
|
|
|
|
*
|
|
|
|
* Returns number of bytes read or error code, as appropriate
|
|
|
|
*/
|
|
|
|
static ssize_t smk_read_onlycap(struct file *filp, char __user *buf,
|
|
|
|
size_t cn, loff_t *ppos)
|
|
|
|
{
|
|
|
|
char *smack = "";
|
|
|
|
ssize_t rc = -EINVAL;
|
|
|
|
int asize;
|
|
|
|
|
|
|
|
if (*ppos != 0)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
if (smack_onlycap != NULL)
|
|
|
|
smack = smack_onlycap;
|
|
|
|
|
|
|
|
asize = strlen(smack) + 1;
|
|
|
|
|
|
|
|
if (cn >= asize)
|
|
|
|
rc = simple_read_from_buffer(buf, cn, ppos, smack, asize);
|
|
|
|
|
|
|
|
return rc;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_write_onlycap - write() for /smack/onlycap
|
2009-02-19 03:42:33 +08:00
|
|
|
* @file: file pointer, not actually used
|
2008-07-31 06:37:11 +08:00
|
|
|
* @buf: where to get the data from
|
|
|
|
* @count: bytes sent
|
|
|
|
* @ppos: where to start
|
|
|
|
*
|
|
|
|
* Returns number of bytes written or error code, as appropriate
|
|
|
|
*/
|
|
|
|
static ssize_t smk_write_onlycap(struct file *file, const char __user *buf,
|
|
|
|
size_t count, loff_t *ppos)
|
|
|
|
{
|
|
|
|
char in[SMK_LABELLEN];
|
2008-11-14 07:39:16 +08:00
|
|
|
char *sp = current->cred->security;
|
2008-07-31 06:37:11 +08:00
|
|
|
|
|
|
|
if (!capable(CAP_MAC_ADMIN))
|
|
|
|
return -EPERM;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* This can be done using smk_access() but is done
|
|
|
|
* explicitly for clarity. The smk_access() implementation
|
|
|
|
* would use smk_access(smack_onlycap, MAY_WRITE)
|
|
|
|
*/
|
|
|
|
if (smack_onlycap != NULL && smack_onlycap != sp)
|
|
|
|
return -EPERM;
|
|
|
|
|
|
|
|
if (count >= SMK_LABELLEN)
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
if (copy_from_user(in, buf, count) != 0)
|
|
|
|
return -EFAULT;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Should the null string be passed in unset the onlycap value.
|
|
|
|
* This seems like something to be careful with as usually
|
|
|
|
* smk_import only expects to return NULL for errors. It
|
|
|
|
* is usually the case that a nullstring or "\n" would be
|
|
|
|
* bad to pass to smk_import but in fact this is useful here.
|
|
|
|
*/
|
|
|
|
smack_onlycap = smk_import(in, count);
|
|
|
|
|
|
|
|
return count;
|
|
|
|
}
|
|
|
|
|
|
|
|
static const struct file_operations smk_onlycap_ops = {
|
|
|
|
.read = smk_read_onlycap,
|
|
|
|
.write = smk_write_onlycap,
|
|
|
|
};
|
|
|
|
|
2009-04-09 02:40:06 +08:00
|
|
|
/**
|
|
|
|
* smk_read_logging - read() for /smack/logging
|
|
|
|
* @filp: file pointer, not actually used
|
|
|
|
* @buf: where to put the result
|
|
|
|
* @cn: maximum to send along
|
|
|
|
* @ppos: where to start
|
|
|
|
*
|
|
|
|
* Returns number of bytes read or error code, as appropriate
|
|
|
|
*/
|
|
|
|
static ssize_t smk_read_logging(struct file *filp, char __user *buf,
|
|
|
|
size_t count, loff_t *ppos)
|
|
|
|
{
|
|
|
|
char temp[32];
|
|
|
|
ssize_t rc;
|
|
|
|
|
|
|
|
if (*ppos != 0)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
sprintf(temp, "%d\n", log_policy);
|
|
|
|
rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
|
|
|
|
return rc;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_write_logging - write() for /smack/logging
|
|
|
|
* @file: file pointer, not actually used
|
|
|
|
* @buf: where to get the data from
|
|
|
|
* @count: bytes sent
|
|
|
|
* @ppos: where to start
|
|
|
|
*
|
|
|
|
* Returns number of bytes written or error code, as appropriate
|
|
|
|
*/
|
|
|
|
static ssize_t smk_write_logging(struct file *file, const char __user *buf,
|
|
|
|
size_t count, loff_t *ppos)
|
|
|
|
{
|
|
|
|
char temp[32];
|
|
|
|
int i;
|
|
|
|
|
|
|
|
if (!capable(CAP_MAC_ADMIN))
|
|
|
|
return -EPERM;
|
|
|
|
|
|
|
|
if (count >= sizeof(temp) || count == 0)
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
if (copy_from_user(temp, buf, count) != 0)
|
|
|
|
return -EFAULT;
|
|
|
|
|
|
|
|
temp[count] = '\0';
|
|
|
|
|
|
|
|
if (sscanf(temp, "%d", &i) != 1)
|
|
|
|
return -EINVAL;
|
|
|
|
if (i < 0 || i > 3)
|
|
|
|
return -EINVAL;
|
|
|
|
log_policy = i;
|
|
|
|
return count;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
static const struct file_operations smk_logging_ops = {
|
|
|
|
.read = smk_read_logging,
|
|
|
|
.write = smk_write_logging,
|
|
|
|
};
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
/**
|
|
|
|
* smk_fill_super - fill the /smackfs superblock
|
|
|
|
* @sb: the empty superblock
|
|
|
|
* @data: unused
|
|
|
|
* @silent: unused
|
|
|
|
*
|
|
|
|
* Fill in the well known entries for /smack
|
|
|
|
*
|
|
|
|
* Returns 0 on success, an error code on failure
|
|
|
|
*/
|
|
|
|
static int smk_fill_super(struct super_block *sb, void *data, int silent)
|
|
|
|
{
|
|
|
|
int rc;
|
|
|
|
struct inode *root_inode;
|
|
|
|
|
|
|
|
static struct tree_descr smack_files[] = {
|
|
|
|
[SMK_LOAD] =
|
|
|
|
{"load", &smk_load_ops, S_IRUGO|S_IWUSR},
|
|
|
|
[SMK_CIPSO] =
|
|
|
|
{"cipso", &smk_cipso_ops, S_IRUGO|S_IWUSR},
|
|
|
|
[SMK_DOI] =
|
|
|
|
{"doi", &smk_doi_ops, S_IRUGO|S_IWUSR},
|
|
|
|
[SMK_DIRECT] =
|
|
|
|
{"direct", &smk_direct_ops, S_IRUGO|S_IWUSR},
|
|
|
|
[SMK_AMBIENT] =
|
|
|
|
{"ambient", &smk_ambient_ops, S_IRUGO|S_IWUSR},
|
2009-01-01 01:54:12 +08:00
|
|
|
[SMK_NETLBLADDR] =
|
|
|
|
{"netlabel", &smk_netlbladdr_ops, S_IRUGO|S_IWUSR},
|
2008-07-31 06:37:11 +08:00
|
|
|
[SMK_ONLYCAP] =
|
|
|
|
{"onlycap", &smk_onlycap_ops, S_IRUGO|S_IWUSR},
|
2009-04-09 02:40:06 +08:00
|
|
|
[SMK_LOGGING] =
|
|
|
|
{"logging", &smk_logging_ops, S_IRUGO|S_IWUSR},
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
/* last one */ {""}
|
|
|
|
};
|
|
|
|
|
|
|
|
rc = simple_fill_super(sb, SMACK_MAGIC, smack_files);
|
|
|
|
if (rc != 0) {
|
|
|
|
printk(KERN_ERR "%s failed %d while creating inodes\n",
|
|
|
|
__func__, rc);
|
|
|
|
return rc;
|
|
|
|
}
|
|
|
|
|
|
|
|
root_inode = sb->s_root->d_inode;
|
|
|
|
root_inode->i_security = new_inode_smack(smack_known_floor.smk_known);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* smk_get_sb - get the smackfs superblock
|
|
|
|
* @fs_type: passed along without comment
|
|
|
|
* @flags: passed along without comment
|
|
|
|
* @dev_name: passed along without comment
|
|
|
|
* @data: passed along without comment
|
|
|
|
* @mnt: passed along without comment
|
|
|
|
*
|
|
|
|
* Just passes everything along.
|
|
|
|
*
|
|
|
|
* Returns what the lower level code does.
|
|
|
|
*/
|
|
|
|
static int smk_get_sb(struct file_system_type *fs_type,
|
|
|
|
int flags, const char *dev_name, void *data,
|
|
|
|
struct vfsmount *mnt)
|
|
|
|
{
|
|
|
|
return get_sb_single(fs_type, flags, data, smk_fill_super, mnt);
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct file_system_type smk_fs_type = {
|
|
|
|
.name = "smackfs",
|
|
|
|
.get_sb = smk_get_sb,
|
|
|
|
.kill_sb = kill_litter_super,
|
|
|
|
};
|
|
|
|
|
|
|
|
static struct vfsmount *smackfs_mount;
|
|
|
|
|
|
|
|
/**
|
|
|
|
* init_smk_fs - get the smackfs superblock
|
|
|
|
*
|
|
|
|
* register the smackfs
|
|
|
|
*
|
2008-03-07 00:09:10 +08:00
|
|
|
* Do not register smackfs if Smack wasn't enabled
|
|
|
|
* on boot. We can not put this method normally under the
|
|
|
|
* smack_init() code path since the security subsystem get
|
|
|
|
* initialized before the vfs caches.
|
|
|
|
*
|
|
|
|
* Returns true if we were not chosen on boot or if
|
|
|
|
* we were chosen and filesystem registration succeeded.
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
*/
|
|
|
|
static int __init init_smk_fs(void)
|
|
|
|
{
|
|
|
|
int err;
|
|
|
|
|
2008-03-07 00:09:10 +08:00
|
|
|
if (!security_module_enable(&smack_ops))
|
|
|
|
return 0;
|
|
|
|
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
|
|
|
err = register_filesystem(&smk_fs_type);
|
|
|
|
if (!err) {
|
|
|
|
smackfs_mount = kern_mount(&smk_fs_type);
|
|
|
|
if (IS_ERR(smackfs_mount)) {
|
|
|
|
printk(KERN_ERR "smackfs: could not mount!\n");
|
|
|
|
err = PTR_ERR(smackfs_mount);
|
|
|
|
smackfs_mount = NULL;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
smk_cipso_doi();
|
2008-02-16 07:24:25 +08:00
|
|
|
smk_unlbl_ambient(NULL);
|
Smack: Simplified Mandatory Access Control Kernel
Smack is the Simplified Mandatory Access Control Kernel.
Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.
Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.
The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on
http://www.schaufler-ca.com
Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.
Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".
A file always gets the Smack label of the task that created it.
Smack defines and uses these labels:
"*" - pronounced "star"
"_" - pronounced "floor"
"^" - pronounced "hat"
"?" - pronounced "huh"
The access rules enforced by Smack are, in order:
1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
is permitted.
3. A read or execute access requested on an object labeled "_"
is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
label is permitted.
6. Any access requested that is explicitly defined in the loaded
rule set is permitted.
7. Any other access is denied.
Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.
Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.
Some practical use cases:
Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:
C Unclass rx
S C rx
S Unclass rx
TS S rx
TS C rx
TS Unclass rx
A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.
Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.
A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:
A case that Bell&LaPadula does not allow that Smack does:
ESPN ABC r
ABC ESPN r
On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.
Another case that I especially like:
SatData Guard w
Guard Publish w
A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.
The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 14:29:50 +08:00
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return err;
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}
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__initcall(init_smk_fs);
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