The new templates management mechanism records information associated
to an event into an array of 'ima_field_data' structures and makes it
available through the 'template_data' field of the 'ima_template_entry'
structure (the element of the measurements list created by IMA).
Since 'ima_field_data' contains dynamically allocated data (which length
varies depending on the data associated to a selected template field),
it is not enough to just free the memory reserved for a
'ima_template_entry' structure if something goes wrong.
This patch creates the new function ima_free_template_entry() which
walks the array of 'ima_field_data' structures, frees the memory
referenced by the 'data' pointer and finally the space reserved for
the 'ima_template_entry' structure. Further, it replaces existing kfree()
that have a pointer to an 'ima_template_entry' structure as argument
with calls to the new function.
Fixes: a71dc65: ima: switch to new template management mechanism
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
7bc5f447ce (ima: define new function ima_alloc_init_template() to
API) moved the initialization of 'entry' in ima_add_boot_aggregate() a
bit more below, after the if (ima_used_chip).
So, 'entry' is not initialized while being inside this if-block. So, we
should not attempt to free it.
Found by Coverity (CID: 1131971)
Fixes: 7bc5f447ce (ima: define new function ima_alloc_init_template() to API)
Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
This patch stores the address of the 'template_fmt_copy' variable in a new
variable, called 'template_fmt_ptr', so that the latter is passed as an
argument of strsep() instead of the former. This modification is needed
in order to correctly free the memory area referenced by
'template_fmt_copy' (strsep() modifies the pointer of the passed string).
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Reported-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
This patch defines a new value for the 'ima_show_type' enumerator
(IMA_SHOW_BINARY_NO_FIELD_LEN) to prevent that the field length
is transmitted through the 'binary_runtime_measurements' interface
for the digest field of the 'ima' template.
Fixes commit: 3ce1217 ima: define template fields library and new helpers
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
To maintain compatibility with userspace tools, the field length must not
be included in the template digest calculation for the 'ima' template.
Fixes commit: a71dc65 ima: switch to new template management mechanism
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This reverts commit 217091dd7a, which
caused the following build error:
security/integrity/digsig.c:70:5: error: redefinition of ‘integrity_init_keyring’
security/integrity/integrity.h:149:12: note: previous definition of ‘integrity_init_keyring’ w
security/integrity/integrity.h:149:12: warning: ‘integrity_init_keyring’ defined but not used
reported by Krzysztof Kolasa. Mimi says:
"I made the classic mistake of requesting this patch to be upstreamed
at the last second, rather than waiting until the next open window.
At this point, the best course would probably be to revert the two
commits and fix them for the next open window"
Reported-by: Krzysztof Kolasa <kkolasa@winsoft.pl>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull security subsystem updates from James Morris:
"In this patchset, we finally get an SELinux update, with Paul Moore
taking over as maintainer of that code.
Also a significant update for the Keys subsystem, as well as
maintenance updates to Smack, IMA, TPM, and Apparmor"
and since I wanted to know more about the updates to key handling,
here's the explanation from David Howells on that:
"Okay. There are a number of separate bits. I'll go over the big bits
and the odd important other bit, most of the smaller bits are just
fixes and cleanups. If you want the small bits accounting for, I can
do that too.
(1) Keyring capacity expansion.
KEYS: Consolidate the concept of an 'index key' for key access
KEYS: Introduce a search context structure
KEYS: Search for auth-key by name rather than target key ID
Add a generic associative array implementation.
KEYS: Expand the capacity of a keyring
Several of the patches are providing an expansion of the capacity of a
keyring. Currently, the maximum size of a keyring payload is one page.
Subtract a small header and then divide up into pointers, that only gives
you ~500 pointers on an x86_64 box. However, since the NFS idmapper uses
a keyring to store ID mapping data, that has proven to be insufficient to
the cause.
Whatever data structure I use to handle the keyring payload, it can only
store pointers to keys, not the keys themselves because several keyrings
may point to a single key. This precludes inserting, say, and rb_node
struct into the key struct for this purpose.
I could make an rbtree of records such that each record has an rb_node
and a key pointer, but that would use four words of space per key stored
in the keyring. It would, however, be able to use much existing code.
I selected instead a non-rebalancing radix-tree type approach as that
could have a better space-used/key-pointer ratio. I could have used the
radix tree implementation that we already have and insert keys into it by
their serial numbers, but that means any sort of search must iterate over
the whole radix tree. Further, its nodes are a bit on the capacious side
for what I want - especially given that key serial numbers are randomly
allocated, thus leaving a lot of empty space in the tree.
So what I have is an associative array that internally is a radix-tree
with 16 pointers per node where the index key is constructed from the key
type pointer and the key description. This means that an exact lookup by
type+description is very fast as this tells us how to navigate directly to
the target key.
I made the data structure general in lib/assoc_array.c as far as it is
concerned, its index key is just a sequence of bits that leads to a
pointer. It's possible that someone else will be able to make use of it
also. FS-Cache might, for example.
(2) Mark keys as 'trusted' and keyrings as 'trusted only'.
KEYS: verify a certificate is signed by a 'trusted' key
KEYS: Make the system 'trusted' keyring viewable by userspace
KEYS: Add a 'trusted' flag and a 'trusted only' flag
KEYS: Separate the kernel signature checking keyring from module signing
These patches allow keys carrying asymmetric public keys to be marked as
being 'trusted' and allow keyrings to be marked as only permitting the
addition or linkage of trusted keys.
Keys loaded from hardware during kernel boot or compiled into the kernel
during build are marked as being trusted automatically. New keys can be
loaded at runtime with add_key(). They are checked against the system
keyring contents and if their signatures can be validated with keys that
are already marked trusted, then they are marked trusted also and can
thus be added into the master keyring.
Patches from Mimi Zohar make this usable with the IMA keyrings also.
(3) Remove the date checks on the key used to validate a module signature.
X.509: Remove certificate date checks
It's not reasonable to reject a signature just because the key that it was
generated with is no longer valid datewise - especially if the kernel
hasn't yet managed to set the system clock when the first module is
loaded - so just remove those checks.
(4) Make it simpler to deal with additional X.509 being loaded into the kernel.
KEYS: Load *.x509 files into kernel keyring
KEYS: Have make canonicalise the paths of the X.509 certs better to deduplicate
The builder of the kernel now just places files with the extension ".x509"
into the kernel source or build trees and they're concatenated by the
kernel build and stuffed into the appropriate section.
(5) Add support for userspace kerberos to use keyrings.
KEYS: Add per-user_namespace registers for persistent per-UID kerberos caches
KEYS: Implement a big key type that can save to tmpfs
Fedora went to, by default, storing kerberos tickets and tokens in tmpfs.
We looked at storing it in keyrings instead as that confers certain
advantages such as tickets being automatically deleted after a certain
amount of time and the ability for the kernel to get at these tokens more
easily.
To make this work, two things were needed:
(a) A way for the tickets to persist beyond the lifetime of all a user's
sessions so that cron-driven processes can still use them.
The problem is that a user's session keyrings are deleted when the
session that spawned them logs out and the user's user keyring is
deleted when the UID is deleted (typically when the last log out
happens), so neither of these places is suitable.
I've added a system keyring into which a 'persistent' keyring is
created for each UID on request. Each time a user requests their
persistent keyring, the expiry time on it is set anew. If the user
doesn't ask for it for, say, three days, the keyring is automatically
expired and garbage collected using the existing gc. All the kerberos
tokens it held are then also gc'd.
(b) A key type that can hold really big tickets (up to 1MB in size).
The problem is that Active Directory can return huge tickets with lots
of auxiliary data attached. We don't, however, want to eat up huge
tracts of unswappable kernel space for this, so if the ticket is
greater than a certain size, we create a swappable shmem file and dump
the contents in there and just live with the fact we then have an
inode and a dentry overhead. If the ticket is smaller than that, we
slap it in a kmalloc()'d buffer"
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (121 commits)
KEYS: Fix keyring content gc scanner
KEYS: Fix error handling in big_key instantiation
KEYS: Fix UID check in keyctl_get_persistent()
KEYS: The RSA public key algorithm needs to select MPILIB
ima: define '_ima' as a builtin 'trusted' keyring
ima: extend the measurement list to include the file signature
kernel/system_certificate.S: use real contents instead of macro GLOBAL()
KEYS: fix error return code in big_key_instantiate()
KEYS: Fix keyring quota misaccounting on key replacement and unlink
KEYS: Fix a race between negating a key and reading the error set
KEYS: Make BIG_KEYS boolean
apparmor: remove the "task" arg from may_change_ptraced_domain()
apparmor: remove parent task info from audit logging
apparmor: remove tsk field from the apparmor_audit_struct
apparmor: fix capability to not use the current task, during reporting
Smack: Ptrace access check mode
ima: provide hash algo info in the xattr
ima: enable support for larger default filedata hash algorithms
ima: define kernel parameter 'ima_template=' to change configured default
ima: add Kconfig default measurement list template
...
Pull audit updates from Eric Paris:
"Nothing amazing. Formatting, small bug fixes, couple of fixes where
we didn't get records due to some old VFS changes, and a change to how
we collect execve info..."
Fixed conflict in fs/exec.c as per Eric and linux-next.
* git://git.infradead.org/users/eparis/audit: (28 commits)
audit: fix type of sessionid in audit_set_loginuid()
audit: call audit_bprm() only once to add AUDIT_EXECVE information
audit: move audit_aux_data_execve contents into audit_context union
audit: remove unused envc member of audit_aux_data_execve
audit: Kill the unused struct audit_aux_data_capset
audit: do not reject all AUDIT_INODE filter types
audit: suppress stock memalloc failure warnings since already managed
audit: log the audit_names record type
audit: add child record before the create to handle case where create fails
audit: use given values in tty_audit enable api
audit: use nlmsg_len() to get message payload length
audit: use memset instead of trying to initialize field by field
audit: fix info leak in AUDIT_GET requests
audit: update AUDIT_INODE filter rule to comparator function
audit: audit feature to set loginuid immutable
audit: audit feature to only allow unsetting the loginuid
audit: allow unsetting the loginuid (with priv)
audit: remove CONFIG_AUDIT_LOGINUID_IMMUTABLE
audit: loginuid functions coding style
selinux: apply selinux checks on new audit message types
...
Key pointers stored in the keyring are marked in bit 1 to indicate if they
point to a keyring. We need to strip off this bit before using the pointer
when iterating over the keyring for the purpose of looking for links to garbage
collect.
This means that expirable keyrings aren't correctly expiring because the
checker is seeing their key pointer with 2 added to it.
Since the fix for this involves knowing about the internals of the keyring,
key_gc_keyring() is moved to keyring.c and merged into keyring_gc().
This can be tested by:
echo 2 >/proc/sys/kernel/keys/gc_delay
keyctl timeout `keyctl add keyring qwerty "" @s` 2
cat /proc/keys
sleep 5; cat /proc/keys
which should see a keyring called "qwerty" appear in the session keyring and
then disappear after it expires, and:
echo 2 >/proc/sys/kernel/keys/gc_delay
a=`keyctl get_persistent @s`
b=`keyctl add keyring 0 "" $a`
keyctl add user a a $b
keyctl timeout $b 2
cat /proc/keys
sleep 5; cat /proc/keys
which should see a keyring called "0" with a key called "a" in it appear in the
user's persistent keyring (which will be attached to the session keyring) and
then both the "0" keyring and the "a" key should disappear when the "0" keyring
expires.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Simo Sorce <simo@redhat.com>
In the big_key_instantiate() function we return 0 if kernel_write() returns us
an error rather than returning an error. This can potentially lead to
dentry_open() giving a BUG when called from big_key_read() with an unset
tmpfile path.
------------[ cut here ]------------
kernel BUG at fs/open.c:798!
...
RIP: 0010:[<ffffffff8119bbd1>] dentry_open+0xd1/0xe0
...
Call Trace:
[<ffffffff812350c5>] big_key_read+0x55/0x100
[<ffffffff81231084>] keyctl_read_key+0xb4/0xe0
[<ffffffff81231e58>] SyS_keyctl+0xf8/0x1d0
[<ffffffff815bb799>] system_call_fastpath+0x16/0x1b
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Stephen Gallagher <sgallagh@redhat.com>
Pull networking updates from David Miller:
1) The addition of nftables. No longer will we need protocol aware
firewall filtering modules, it can all live in userspace.
At the core of nftables is a, for lack of a better term, virtual
machine that executes byte codes to inspect packet or metadata
(arriving interface index, etc.) and make verdict decisions.
Besides support for loading packet contents and comparing them, the
interpreter supports lookups in various datastructures as
fundamental operations. For example sets are supports, and
therefore one could create a set of whitelist IP address entries
which have ACCEPT verdicts attached to them, and use the appropriate
byte codes to do such lookups.
Since the interpreted code is composed in userspace, userspace can
do things like optimize things before giving it to the kernel.
Another major improvement is the capability of atomically updating
portions of the ruleset. In the existing netfilter implementation,
one has to update the entire rule set in order to make a change and
this is very expensive.
Userspace tools exist to create nftables rules using existing
netfilter rule sets, but both kernel implementations will need to
co-exist for quite some time as we transition from the old to the
new stuff.
Kudos to Patrick McHardy, Pablo Neira Ayuso, and others who have
worked so hard on this.
2) Daniel Borkmann and Hannes Frederic Sowa made several improvements
to our pseudo-random number generator, mostly used for things like
UDP port randomization and netfitler, amongst other things.
In particular the taus88 generater is updated to taus113, and test
cases are added.
3) Support 64-bit rates in HTB and TBF schedulers, from Eric Dumazet
and Yang Yingliang.
4) Add support for new 577xx tigon3 chips to tg3 driver, from Nithin
Sujir.
5) Fix two fatal flaws in TCP dynamic right sizing, from Eric Dumazet,
Neal Cardwell, and Yuchung Cheng.
6) Allow IP_TOS and IP_TTL to be specified in sendmsg() ancillary
control message data, much like other socket option attributes.
From Francesco Fusco.
7) Allow applications to specify a cap on the rate computed
automatically by the kernel for pacing flows, via a new
SO_MAX_PACING_RATE socket option. From Eric Dumazet.
8) Make the initial autotuned send buffer sizing in TCP more closely
reflect actual needs, from Eric Dumazet.
9) Currently early socket demux only happens for TCP sockets, but we
can do it for connected UDP sockets too. Implementation from Shawn
Bohrer.
10) Refactor inet socket demux with the goal of improving hash demux
performance for listening sockets. With the main goals being able
to use RCU lookups on even request sockets, and eliminating the
listening lock contention. From Eric Dumazet.
11) The bonding layer has many demuxes in it's fast path, and an RCU
conversion was started back in 3.11, several changes here extend the
RCU usage to even more locations. From Ding Tianhong and Wang
Yufen, based upon suggestions by Nikolay Aleksandrov and Veaceslav
Falico.
12) Allow stackability of segmentation offloads to, in particular, allow
segmentation offloading over tunnels. From Eric Dumazet.
13) Significantly improve the handling of secret keys we input into the
various hash functions in the inet hashtables, TCP fast open, as
well as syncookies. From Hannes Frederic Sowa. The key fundamental
operation is "net_get_random_once()" which uses static keys.
Hannes even extended this to ipv4/ipv6 fragmentation handling and
our generic flow dissector.
14) The generic driver layer takes care now to set the driver data to
NULL on device removal, so it's no longer necessary for drivers to
explicitly set it to NULL any more. Many drivers have been cleaned
up in this way, from Jingoo Han.
15) Add a BPF based packet scheduler classifier, from Daniel Borkmann.
16) Improve CRC32 interfaces and generic SKB checksum iterators so that
SCTP's checksumming can more cleanly be handled. Also from Daniel
Borkmann.
17) Add a new PMTU discovery mode, IP_PMTUDISC_INTERFACE, which forces
using the interface MTU value. This helps avoid PMTU attacks,
particularly on DNS servers. From Hannes Frederic Sowa.
18) Use generic XPS for transmit queue steering rather than internal
(re-)implementation in virtio-net. From Jason Wang.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1622 commits)
random32: add test cases for taus113 implementation
random32: upgrade taus88 generator to taus113 from errata paper
random32: move rnd_state to linux/random.h
random32: add prandom_reseed_late() and call when nonblocking pool becomes initialized
random32: add periodic reseeding
random32: fix off-by-one in seeding requirement
PHY: Add RTL8201CP phy_driver to realtek
xtsonic: add missing platform_set_drvdata() in xtsonic_probe()
macmace: add missing platform_set_drvdata() in mace_probe()
ethernet/arc/arc_emac: add missing platform_set_drvdata() in arc_emac_probe()
ipv6: protect for_each_sk_fl_rcu in mem_check with rcu_read_lock_bh
vlan: Implement vlan_dev_get_egress_qos_mask as an inline.
ixgbe: add warning when max_vfs is out of range.
igb: Update link modes display in ethtool
netfilter: push reasm skb through instead of original frag skbs
ip6_output: fragment outgoing reassembled skb properly
MAINTAINERS: mv643xx_eth: take over maintainership from Lennart
net_sched: tbf: support of 64bit rates
ixgbe: deleting dfwd stations out of order can cause null ptr deref
ixgbe: fix build err, num_rx_queues is only available with CONFIG_RPS
...
Pull cgroup changes from Tejun Heo:
"Not too much activity this time around. css_id is finally killed and
a minor update to device_cgroup"
* 'for-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
device_cgroup: remove can_attach
cgroup: kill css_id
memcg: stop using css id
memcg: fail to create cgroup if the cgroup id is too big
memcg: convert to use cgroup id
memcg: convert to use cgroup_is_descendant()
If the UID is specified by userspace when calling the KEYCTL_GET_PERSISTENT
function and the process does not have the CAP_SETUID capability, then the
function will return -EPERM if the current process's uid, suid, euid and fsuid
all match the requested UID. This is incorrect.
Fix it such that when a non-privileged caller requests a persistent keyring by
a specific UID they can only request their own (ie. the specified UID matches
either then process's UID or the process's EUID).
This can be tested by logging in as the user and doing:
keyctl get_persistent @p
keyctl get_persistent @p `id -u`
keyctl get_persistent @p 0
The first two should successfully print the same key ID. The third should do
the same if called by UID 0 or indicate Operation Not Permitted otherwise.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Stephen Gallagher <sgallagh@redhat.com>
Supress the stock memory allocation failure warnings for audit buffers
since audit alreay takes care of memory allocation failure warnings, including
rate-limiting, in audit_log_start().
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
We use the read check to get the feature set (like AUDIT_GET) and the
write check to set the features (like AUDIT_SET).
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Require all keys added to the IMA keyring be signed by an
existing trusted key on the system trusted keyring.
Changelog:
- define stub integrity_init_keyring() function (reported-by Fengguang Wu)
- differentiate between regular and trusted keyring names.
- replace printk with pr_info (D. Kasatkin)
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
This patch defines a new template called 'ima-sig', which includes
the file signature in the template data, in addition to the file's
digest and pathname.
A template is composed of a set of fields. Associated with each
field is an initialization and display function. This patch defines
a new template field called 'sig', the initialization function
ima_eventsig_init(), and the display function ima_show_template_sig().
This patch modifies the .field_init() function definition to include
the 'security.ima' extended attribute and length.
Changelog:
- remove unused code (Dmitry Kasatkin)
- avoid calling ima_write_template_field_data() unnecesarily (Roberto Sassu)
- rename DATA_FMT_SIG to DATA_FMT_HEX
- cleanup ima_eventsig_init() based on Roberto's comments
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: David Howells <dhowells@redhat.com>
If a key is displaced from a keyring by a matching one, then four more bytes
of quota are allocated to the keyring - despite the fact that the keyring does
not change in size.
Further, when a key is unlinked from a keyring, the four bytes of quota
allocated the link isn't recovered and returned to the user's pool.
The first can be tested by repeating:
keyctl add big_key a fred @s
cat /proc/key-users
(Don't put it in a shell loop otherwise the garbage collector won't have time
to clear the displaced keys, thus affecting the result).
This was causing the kerberos keyring to run out of room fairly quickly.
The second can be tested by:
cat /proc/key-users
a=`keyctl add user a a @s`
cat /proc/key-users
keyctl unlink $a
sleep 1 # Give RCU a chance to delete the key
cat /proc/key-users
assuming no system activity that otherwise adds/removes keys, the amount of
key data allocated should go up (say 40/20000 -> 47/20000) and then return to
the original value at the end.
Reported-by: Stephen Gallagher <sgallagh@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Having the big_keys functionality as a module is very marginally useful.
The userspace code that would use this functionality will get odd error
messages from the keys layer if the module isn't loaded. The code itself
is fairly small, so just have this as a boolean option and not a tristate.
Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Unless task == current ptrace_parent(task) is not safe even under
rcu_read_lock() and most of the current users are not right.
So may_change_ptraced_domain(task) looks wrong as well. However it
is always called with task == current so the code is actually fine.
Remove this argument to make this fact clear.
Note: perhaps we should simply kill ptrace_parent(), it buys almost
nothing. And it is obviously racy, perhaps this should be fixed.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
The reporting of the parent task info is a vestage from old versions of
apparmor. The need for this information was removed by unique null-
profiles before apparmor was upstreamed so remove this info from logging.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Now that aa_capabile no longer sets the task field it can be removed
and the lsm_audit version of the field can be used.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Mediation is based off of the cred but auditing includes the current
task which may not be related to the actual request.
Signed-off-by: John Johansen <john.johansen@canonical.com>
When the ptrace security hooks were split the addition of
a mode parameter was not taken advantage of in the Smack
ptrace access check. This changes the access check from
always looking for read and write access to using the
passed mode. This will make use of /proc much happier.
Targeted for git://git.gitorious.org/smack-next/kernel.git
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
All files labeled with 'security.ima' hashes, are hashed using the
same hash algorithm. Changing from one hash algorithm to another,
requires relabeling the filesystem. This patch defines a new xattr
type, which includes the hash algorithm, permitting different files
to be hashed with different algorithms.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The IMA measurement list contains two hashes - a template data hash
and a filedata hash. The template data hash is committed to the TPM,
which is limited, by the TPM v1.2 specification, to 20 bytes. The
filedata hash is defined as 20 bytes as well.
Now that support for variable length measurement list templates was
added, the filedata hash is not limited to 20 bytes. This patch adds
Kconfig support for defining larger default filedata hash algorithms
and replacing the builtin default with one specified on the kernel
command line.
<uapi/linux/hash_info.h> contains a list of hash algorithms. The
Kconfig default hash algorithm is a subset of this list, but any hash
algorithm included in the list can be specified at boot, using the
'ima_hash=' kernel command line option.
Changelog v2:
- update Kconfig
Changelog:
- support hashes that are configured
- use generic HASH_ALGO_ definitions
- add Kconfig support
- hash_setup must be called only once (Dmitry)
- removed trailing whitespaces (Roberto Sassu)
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
This patch allows users to specify from the kernel command line the
template descriptor, among those defined, that will be used to generate
and display measurement entries. If an user specifies a wrong template,
IMA reverts to the template descriptor set in the kernel configuration.
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch adds a Kconfig option to select the default IMA
measurement list template. The 'ima' template limited the
filedata hash to 20 bytes and the pathname to 255 charaters.
The 'ima-ng' measurement list template permits larger hash
digests and longer pathnames.
Changelog:
- keep 'select CRYPTO_HASH_INFO' in 'config IMA' section (Kconfig)
(Roberto Sassu);
- removed trailing whitespaces (Roberto Sassu).
- Lindent fixes
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
The same hash algorithm should be used for calculating the file
data hash for the IMA measurement list, as for appraising the file
data integrity. (The appraise hash algorithm is stored in the
'security.ima' extended attribute.) The exception is when the
reference file data hash digest, stored in the extended attribute,
is larger than the one supported by the template. In this case,
the file data hash needs to be calculated twice, once for the
measurement list and, again, for appraisal.
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Different files might be signed based on different hash algorithms.
This patch prefixes the audit log measurement hash with the hash
algorithm.
Changelog:
- use generic HASH_ALGO defintions
- use ':' as delimiter between the hash algorithm and the digest
(Roberto Sassu)
- always include the hash algorithm used when audit-logging a measurement
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Peter Moody <pmoody@google.com>
This patch performs the switch to the new template mechanism by modifying
the functions ima_alloc_init_template(), ima_measurements_show() and
ima_ascii_measurements_show(). The old function ima_template_show() was
removed as it is no longer needed. Also, if the template descriptor used
to generate a measurement entry is not 'ima', the whole length of field
data stored for an entry is provided before the data itself through the
binary_runtime_measurement interface.
Changelog:
- unnecessary to use strncmp() (Mimi Zohar)
- create new variable 'field' in ima_alloc_init_template() (Roberto Sassu)
- use GFP_NOFS flag in ima_alloc_init_template() (Roberto Sassu)
- new variable 'num_fields' in ima_store_template() (Roberto Sassu,
proposed by Mimi Zohar)
- rename ima_calc_buffer_hash/template_hash() to ima_calc_field_array_hash(),
something more generic (Mimi, requested by Dmitry)
- sparse error fix - Fengguang Wu
- fix lindent warnings
- always include the field length in the template data length
- include the template field length variable size in the template data length
- include both the template field data and field length in the template digest
calculation. Simplifies verifying the template digest. (Mimi)
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch adds support for the new template 'ima-ng', whose format
is defined as 'd-ng|n-ng'. These new field definitions remove the
size limitations of the original 'ima' template. Further, the 'd-ng'
field prefixes the inode digest with the hash algorithim, when
displaying the new larger digest sizes.
Change log:
- scripts/Lindent fixes - Mimi
- "always true comparison" - reported by Fengguang Wu, resolved Dmitry
- initialize hash_algo variable to HASH_ALGO__LAST
- always prefix digest with hash algorithm - Mimi
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch defines a library containing two initial template fields,
inode digest (d) and file name (n), the 'ima' template descriptor,
whose format is 'd|n', and two helper functions,
ima_write_template_field_data() and ima_show_template_field_data().
Changelog:
- replace ima_eventname_init() parameter NULL checking with BUG_ON.
(suggested by Mimi)
- include "new template fields for inode digest (d) and file name (n)"
definitions to fix a compiler warning. - Mimi
- unnecessary to prefix static function names with 'ima_'. remove
prefix to resolve Lindent formatting changes. - Mimi
- abbreviated/removed inline comments - Mimi
- always send the template field length - Mimi
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The original 'ima' template is fixed length, containing the filedata hash
and pathname. The filedata hash is limited to 20 bytes (md5/sha1). The
pathname is a null terminated string, limited to 255 characters. To
overcome these limitations and to add additional file metadata, it is
necessary to extend the current version of IMA by defining additional
templates.
The main reason to introduce this feature is that, each time a new
template is defined, the functions that generate and display the
measurement list would include the code for handling a new format and,
thus, would significantly grow over time.
This patch set solves this problem by separating the template management
from the remaining IMA code. The core of this solution is the definition
of two new data structures: a template descriptor, to determine which
information should be included in the measurement list, and a template
field, to generate and display data of a given type.
To define a new template field, developers define the field identifier
and implement two functions, init() and show(), respectively to generate
and display measurement entries. Initially, this patch set defines the
following template fields (support for additional data types will be
added later):
- 'd': the digest of the event (i.e. the digest of a measured file),
calculated with the SHA1 or MD5 hash algorithm;
- 'n': the name of the event (i.e. the file name), with size up to
255 bytes;
- 'd-ng': the digest of the event, calculated with an arbitrary hash
algorithm (field format: [<hash algo>:]digest, where the digest
prefix is shown only if the hash algorithm is not SHA1 or MD5);
- 'n-ng': the name of the event, without size limitations.
Defining a new template descriptor requires specifying the template format,
a string of field identifiers separated by the '|' character. This patch
set defines the following template descriptors:
- "ima": its format is 'd|n';
- "ima-ng" (default): its format is 'd-ng|n-ng'
Further details about the new template architecture can be found in
Documentation/security/IMA-templates.txt.
Changelog:
- don't defer calling ima_init_template() - Mimi
- don't define ima_lookup_template_desc() until used - Mimi
- squashed with documentation patch - Mimi
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Instead of allocating and initializing the template entry from multiple
places (eg. boot aggregate, violation, and regular measurements), this
patch defines a new function called ima_alloc_init_template(). The new
function allocates and initializes the measurement entry with the inode
digest and the filename.
In respect to the current behavior, it truncates the file name passed
in the 'filename' argument if the latter's size is greater than 255 bytes
and the passed file descriptor is NULL.
Changelog:
- initialize 'hash' variable for non TPM case - Mimi
- conform to expectation for 'iint' to be defined as a pointer. - Mimi
- add missing 'file' dependency for recalculating file hash. - Mimi
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Pass the filename argument to ima_add_template_entry() in order to
eliminate a dependency on template specific data (third argument of
integrity_audit_msg).
This change is required because, with the new template management
mechanism, the generation of a new measurement entry will be performed
by new specific functions (introduced in next patches) and the current IMA
code will not be aware anymore of how data is stored in the entry payload.
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Pass the file descriptor instead of the inode to ima_add_violation(),
to make the latter consistent with ima_store_measurement() in
preparation for the new template architecture.
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
With multiple hash algorithms, ima_hash_tfm is no longer guaranteed to be sha1.
Need to force to use sha1.
Changelog:
- pass ima_digest_data to ima_calc_boot_aggregate() instead of char *
(Roberto Sassu);
- create an ima_digest_data structure in ima_add_boot_aggregate()
(Roberto Sassu);
- pass hash->algo to ima_alloc_tfm() (Roberto Sassu, reported by Dmitry).
- "move hash definition in ima_add_boot_aggregate()" commit hunk to here.
- sparse warning fix - Fengguang Wu
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
ima_calc_buffer_hash will be used with different hash algorithms.
This patch provides support for arbitrary hash algorithms in
ima_calc_buffer_hash.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch provides dedicated hash algo allocation and
deallocation function which can be used by different clients.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The TPM v1.2 limits the template hash size to 20 bytes. This
patch differentiates between the template hash size, as defined
in the ima_template_entry, and the file data hash size, as
defined in the ima_template_data. Subsequent patches add support
for different file data hash algorithms.
Change log:
- hash digest definition in ima_store_template() should be TPM_DIGEST_SIZE
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
For each inode in the IMA policy, an iint is allocated. To support
larger hash digests, the iint digest size changed from 20 bytes to
the maximum supported hash digest size. Instead of allocating the
maximum size, which most likely is not needed, this patch dynamically
allocates the needed hash storage.
Changelog:
- fix krealloc bug
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
For possibility to use xattr type for new signature formats,
pass full xattr to the signature verification function.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
All files on the filesystem, currently, are hashed using the same hash
algorithm. In preparation for files from different packages being
signed using different hash algorithms, this patch adds support for
reading the signature hash algorithm from the 'security.ima' extended
attribute and calculates the appropriate file data hash based on it.
Changelog:
- fix scripts Lindent and checkpatch msgs - Mimi
- fix md5 support for older version, which occupied 20 bytes in the
xattr, not the expected 16 bytes. Fix the comparison to compare
only the first 16 bytes.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
In preparation of supporting more hash algorithms with larger hash sizes
needed for signature verification, this patch replaces the 20 byte sized
digest, with a more flexible structure. The new structure includes the
hash algorithm, digest size, and digest.
Changelog:
- recalculate filedata hash for the measurement list, if the signature
hash digest size is greater than 20 bytes.
- use generic HASH_ALGO_
- make ima_calc_file_hash static
- scripts lindent and checkpatch fixes
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Roberto Sassu