Commit Graph

151 Commits

Author SHA1 Message Date
Mimi Zohar fdf90729e5 ima: support new kernel module syscall
With the addition of the new kernel module syscall, which defines two
arguments - a file descriptor to the kernel module and a pointer to a NULL
terminated string of module arguments - it is now possible to measure and
appraise kernel modules like any other file on the file system.

This patch adds support to measure and appraise kernel modules in an
extensible and consistent manner.

To support filesystems without extended attribute support, additional
patches could pass the signature as the first parameter.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-12-14 13:05:26 +10:30
Dmitry Kasatkin d26e193622 ima: fix bug in argument order
mask argument goes first, then func, like ima_must_measure
and ima_get_action. ima_inode_post_setattr() assumes that.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-10-05 22:32:16 +10:00
Linus Torvalds 88265322c1 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "Highlights:

   - Integrity: add local fs integrity verification to detect offline
     attacks
   - Integrity: add digital signature verification
   - Simple stacking of Yama with other LSMs (per LSS discussions)
   - IBM vTPM support on ppc64
   - Add new driver for Infineon I2C TIS TPM
   - Smack: add rule revocation for subject labels"

Fixed conflicts with the user namespace support in kernel/auditsc.c and
security/integrity/ima/ima_policy.c.

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (39 commits)
  Documentation: Update git repository URL for Smack userland tools
  ima: change flags container data type
  Smack: setprocattr memory leak fix
  Smack: implement revoking all rules for a subject label
  Smack: remove task_wait() hook.
  ima: audit log hashes
  ima: generic IMA action flag handling
  ima: rename ima_must_appraise_or_measure
  audit: export audit_log_task_info
  tpm: fix tpm_acpi sparse warning on different address spaces
  samples/seccomp: fix 31 bit build on s390
  ima: digital signature verification support
  ima: add support for different security.ima data types
  ima: add ima_inode_setxattr/removexattr function and calls
  ima: add inode_post_setattr call
  ima: replace iint spinblock with rwlock/read_lock
  ima: allocating iint improvements
  ima: add appraise action keywords and default rules
  ima: integrity appraisal extension
  vfs: move ima_file_free before releasing the file
  ...
2012-10-02 21:38:48 -07:00
Eric W. Biederman 8b94eea4bf userns: Add user namespace support to IMA
Use kuid's in the IMA rules.

When reporting the current uid in audit logs use from_kuid
to get a usable value.

Cc: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-09-21 03:13:24 -07:00
Eric W. Biederman cf9c93526f userns: Convert EVM to deal with kuids and kgids in it's hmac computation
Cc: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-09-21 03:13:24 -07:00
Dmitry Kasatkin 0a72ba7aff ima: change flags container data type
IMA audit hashes patches introduced new IMA flags and required
space went beyond 8 bits. Currently the only flag is IMA_DIGSIG.
This patch use 16 bit short instead of 8 bit char.
Without this fix IMA signature will be replaced with hash, which
should not happen.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2012-09-19 08:55:20 -04:00
Peter Moody e7c568e0fd ima: audit log hashes
This adds an 'audit' policy action which audit logs file measurements.

Changelog v6:
 - use new action flag handling (Dmitry Kasatkin).
 - removed whitespace (Mimi)

Changelog v5:
 - use audit_log_untrustedstring.

Changelog v4:
 - cleanup digest -> hash conversion.
 - use filename rather than d_path in ima_audit_measurement.

Changelog v3:
 - Use newly exported audit_log_task_info for logging pid/ppid/uid/etc.
 - Update the ima_policy ABI documentation.

Changelog v2:
 - Use 'audit' action rather than 'measure_and_audit' to permit
 auditing in the absence of measuring..

Changelog v1:
 - Initial posting.

Signed-off-by: Peter Moody <pmoody@google.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2012-09-13 14:48:44 -04:00
Dmitry Kasatkin 45e2472e67 ima: generic IMA action flag handling
Make the IMA action flag handling generic in order to support
additional new actions, without requiring changes to the base
implementation.  New actions, like audit logging, will only
need to modify the define statements.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2012-09-13 14:23:57 -04:00
Dmitry Kasatkin d9d300cdb6 ima: rename ima_must_appraise_or_measure
When AUDIT action support is added to the IMA,
ima_must_appraise_or_measure() does not reflect the real meaning anymore.
Rename it to ima_get_action().

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2012-09-12 07:28:05 -04:00
Dmitry Kasatkin 8606404fa5 ima: digital signature verification support
This patch adds support for digital signature based integrity appraisal.
With this patch, 'security.ima' contains either the file data hash or
a digital signature of the file data hash. The file data hash provides
the security attribute of file integrity. In addition to file integrity,
a digital signature provides the security attribute of authenticity.

Unlike EVM, when the file metadata changes, the digital signature is
replaced with an HMAC, modification of the file data does not cause the
'security.ima' digital signature to be replaced with a hash. As a
result, after any modification, subsequent file integrity appraisals
would fail.

Although digitally signed files can be modified, but by not updating
'security.ima' to reflect these modifications, in essence digitally
signed files could be considered 'immutable'.

IMA uses a different keyring than EVM. While the EVM keyring should not
be updated after initialization and locked, the IMA keyring should allow
updating or adding new keys when upgrading or installing packages.

Changelog v4:
- Change IMA_DIGSIG to hex equivalent
Changelog v3:
- Permit files without any 'security.ima' xattr to be labeled properly.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2012-09-07 14:57:48 -04:00
Mimi Zohar 5a44b41207 ima: add support for different security.ima data types
IMA-appraisal currently verifies the integrity of a file based on a
known 'good' measurement value.  This patch reserves the first byte
of 'security.ima' as a place holder for the type of method used for
verifying file data integrity.

Changelog v1:
- Use the newly defined 'struct evm_ima_xattr_data'

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@nokia.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2012-09-07 14:57:47 -04:00
Mimi Zohar 42c63330f2 ima: add ima_inode_setxattr/removexattr function and calls
Based on xattr_permission comments, the restriction to modify 'security'
xattr is left up to the underlying fs or lsm. Ensure that not just anyone
can modify or remove 'security.ima'.

Changelog v1:
- Unless IMA-APPRAISE is configured, use stub ima_inode_removexattr()/setxattr()
  functions.  (Moved ima_inode_removexattr()/setxattr() to ima_appraise.c)

Changelog:
  - take i_mutex to fix locking (Dmitry Kasatkin)
  - ima_reset_appraise_flags should only be called when modifying or
    removing the 'security.ima' xattr. Requires CAP_SYS_ADMIN privilege.
    (Incorporated fix from Roberto Sassu)
  - Even if allowed to update security.ima, reset the appraisal flags,
    forcing re-appraisal.
  - Replace CAP_MAC_ADMIN with CAP_SYS_ADMIN
  - static inline ima_inode_setxattr()/ima_inode_removexattr() stubs
  - ima_protect_xattr should be static

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
2012-09-07 14:57:47 -04:00
Dmitry Kasatkin a10bf26b2f ima: replace iint spinblock with rwlock/read_lock
For performance, replace the iint spinlock with rwlock/read_lock.

Eric Paris questioned this change, from spinlocks to rwlocks, saying
"rwlocks have been shown to actually be slower on multi processor
systems in a number of cases due to the cache line bouncing required."

Based on performance measurements compiling the kernel on a cold
boot with multiple jobs with/without this patch, Dmitry Kasatkin
and I found that rwlocks performed better than spinlocks, but very
insignificantly.  For example with total compilation time around 6
minutes, with rwlocks time was 1 - 3 seconds shorter... but always
like that.

Changelog v2:
- new patch taken from the 'allocating iint improvements' patch

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2012-09-07 14:57:46 -04:00
Dmitry Kasatkin bf2276d10c ima: allocating iint improvements
With IMA-appraisal's removal of the iint mutex and taking the i_mutex
instead, allocating the iint becomes a lot simplier, as we don't need
to be concerned with two processes racing to allocate the iint. This
patch cleans up and improves performance for allocating the iint.

- removed redundant double i_mutex locking
- combined iint allocation with tree search

Changelog v2:
- removed the rwlock/read_lock changes from this patch

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2012-09-07 14:57:45 -04:00
Mimi Zohar 07f6a79415 ima: add appraise action keywords and default rules
Unlike the IMA measurement policy, the appraise policy can not be dependent
on runtime process information, such as the task uid, as the 'security.ima'
xattr is written on file close and must be updated each time the file changes,
regardless of the current task uid.

This patch extends the policy language with 'fowner', defines an appraise
policy, which appraises all files owned by root, and defines 'ima_appraise_tcb',
a new boot command line option, to enable the appraise policy.

Changelog v3:
- separate the measure from the appraise rules in order to support measuring
  without appraising and appraising without measuring.
- change appraisal default for filesystems without xattr support to fail
- update default appraise policy for cgroups

Changelog v1:
- don't appraise RAMFS (Dmitry Kasatkin)
- merged rest of "ima: ima_must_appraise_or_measure API change" commit
  (Dmtiry Kasatkin)

  ima_must_appraise_or_measure() called ima_match_policy twice, which
  searched the policy for a matching rule.  Once for a matching measurement
  rule and subsequently for an appraisal rule. Searching the policy twice
  is unnecessary overhead, which could be noticeable with a large policy.

  The new version of ima_must_appraise_or_measure() does everything in a
  single iteration using a new version of ima_match_policy().  It returns
  IMA_MEASURE, IMA_APPRAISE mask.

  With the use of action mask only one efficient matching function
  is enough.  Removed other specific versions of matching functions.

Changelog:
- change 'owner' to 'fowner' to conform to the new LSM conditions posted by
  Roberto Sassu.
- fix calls to ima_log_string()

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
2012-09-07 14:57:45 -04:00
Mimi Zohar 2fe5d6def1 ima: integrity appraisal extension
IMA currently maintains an integrity measurement list used to assert the
integrity of the running system to a third party.  The IMA-appraisal
extension adds local integrity validation and enforcement of the
measurement against a "good" value stored as an extended attribute
'security.ima'.  The initial methods for validating 'security.ima' are
hashed based, which provides file data integrity, and digital signature
based, which in addition to providing file data integrity, provides
authenticity.

This patch creates and maintains the 'security.ima' xattr, containing
the file data hash measurement.  Protection of the xattr is provided by
EVM, if enabled and configured.

Based on policy, IMA calls evm_verifyxattr() to verify a file's metadata
integrity and, assuming success, compares the file's current hash value
with the one stored as an extended attribute in 'security.ima'.

Changelov v4:
- changed iint cache flags to hex values

Changelog v3:
- change appraisal default for filesystems without xattr support to fail

Changelog v2:
- fix audit msg 'res' value
- removed unused 'ima_appraise=' values

Changelog v1:
- removed unused iint mutex (Dmitry Kasatkin)
- setattr hook must not reset appraised (Dmitry Kasatkin)
- evm_verifyxattr() now differentiates between no 'security.evm' xattr
  (INTEGRITY_NOLABEL) and no EVM 'protected' xattrs included in the
  'security.evm' (INTEGRITY_NOXATTRS).
- replace hash_status with ima_status (Dmitry Kasatkin)
- re-initialize slab element ima_status on free (Dmitry Kasatkin)
- include 'security.ima' in EVM if CONFIG_IMA_APPRAISE, not CONFIG_IMA
- merged half "ima: ima_must_appraise_or_measure API change" (Dmitry Kasatkin)
- removed unnecessary error variable in process_measurement() (Dmitry Kasatkin)
- use ima_inode_post_setattr() stub function, if IMA_APPRAISE not configured
  (moved ima_inode_post_setattr() to ima_appraise.c)
- make sure ima_collect_measurement() can read file

Changelog:
- add 'iint' to evm_verifyxattr() call (Dimitry Kasatkin)
- fix the race condition between chmod, which takes the i_mutex and then
  iint->mutex, and ima_file_free() and process_measurement(), which take
  the locks in the reverse order, by eliminating iint->mutex. (Dmitry Kasatkin)
- cleanup of ima_appraise_measurement() (Dmitry Kasatkin)
- changes as a result of the iint not allocated for all regular files, but
  only for those measured/appraised.
- don't try to appraise new/empty files
- expanded ima_appraisal description in ima/Kconfig
- IMA appraise definitions required even if IMA_APPRAISE not enabled
- add return value to ima_must_appraise() stub
- unconditionally set status = INTEGRITY_PASS *after* testing status,
  not before.  (Found by Joe Perches)

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
2012-09-07 14:57:44 -04:00
Kent Yoder 20328b56cd ima: enable the IBM vTPM as the default TPM in the PPC64 case
Enable tpm_ibmvtpm driver by default when IMA is enabled on PPC64

Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2012-08-22 16:23:23 -05:00
Dmitry Kasatkin 417c6c8ee2 ima: audit is compiled only when enabled
IMA auditing code was compiled even when CONFIG_AUDIT was not enabled.
This patch compiles auditing code only when possible and enabled.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2012-07-05 16:43:59 -04:00
Dmitry Kasatkin 7ff2267af5 ima: ima_initialized is set only if successful
Set ima_initialized only if initialization was successful.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2012-07-05 16:43:57 -04:00
Dmitry Kasatkin 8445d64dd7 ima: add policy for pseudo fs
Exclude DEVPTS and BINFMT filesystems from the measurement policy.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2012-07-05 16:42:33 -04:00
Dmitry Kasatkin c7de7adc18 ima: remove unused cleanup functions
IMA cannot be used as module and does not need __exit functions.
Removed them.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2012-07-02 16:43:30 -04:00
Dmitry Kasatkin 0ea4f8ae41 ima: free securityfs violations file
On ima_fs_init() error, free securityfs violations file.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2012-07-02 16:43:30 -04:00
Mimi Zohar 08e1b76ae3 ima: use full pathnames in measurement list
The IMA measurement list contains filename hints, which can be
ambigious without the full pathname.  This patch replaces the
filename hint with the full pathname, simplifying for userspace
the correlating of file hash measurements with files.

Change log v1:
- Revert to short filenames, when full pathname is longer than IMA
  measurement buffer size. (Based on Dmitry's review)

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2012-07-02 16:43:29 -04:00
Mimi Zohar fbbb456347 ima: fix filename hint to reflect script interpreter name
When IMA was first upstreamed, the bprm filename and interp were
always the same.  Currently, the bprm->filename and bprm->interp
are the same, except for when only bprm->interp contains the
interpreter name.  So instead of using the bprm->filename as
the IMA filename hint in the measurement list, we could replace
it with bprm->interp, but this feels too fragil.

The following patch is not much better, but at least there is some
indication that sometimes we're passing the filename and other times
the interpreter name.

Reported-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-05-16 10:36:41 +10:00
Randy Dunlap a69f158902 security: fix ima kconfig warning
Fix IMA kconfig warning on non-X86 architectures:

warning: (IMA) selects TCG_TIS which has unmet direct dependencies
(TCG_TPM && X86)

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-02-28 11:01:15 +11:00
Eric Paris b0d5de4d58 IMA: fix audit res field to indicate 1 for success and 0 for failure
The audit res field ususally indicates success with a 1 and 0 for a
failure.  So make IMA do it the same way.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-16 12:01:42 +11:00
James Morris 9e3ff38647 Merge branch 'next-queue' into next 2012-02-09 17:02:34 +11:00
Dmitry Kasatkin 4c2c392763 ima: policy for RAMFS
Don't measure ramfs files.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2012-01-19 21:30:21 -05:00
Fabio Estevam f4a0391dfa ima: fix Kconfig dependencies
Fix the following build warning:
warning: (IMA) selects TCG_TPM which has unmet direct dependencies
(HAS_IOMEM && EXPERIMENTAL)

Suggested-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2012-01-19 21:30:09 -05:00
Mimi Zohar 3db59dd933 ima: fix cred sparse warning
Fix ima_policy.c sparse "warning: dereference of noderef expression"
message, by accessing cred->uid using current_cred().

Changelog v1:
- Change __cred to just cred (based on David Howell's comment)

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2012-01-19 15:59:11 +11:00
Linus Torvalds a25a2b8409 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  integrity: digital signature config option name change
  lib: Removed MPILIB, MPILIB_EXTRA, and SIGNATURE prompts
  lib: MPILIB Kconfig description update
  lib: digital signature dependency fix
  lib: digital signature config option name change
  encrypted-keys: fix rcu and sparse messages
  keys: fix trusted/encrypted keys sparse rcu_assign_pointer messages
  KEYS: Add missing smp_rmb() primitives to the keyring search code
  TOMOYO: Accept \000 as a valid character.
  security: update MAINTAINERS file with new git repo
2012-01-17 16:43:39 -08:00
Dmitry Kasatkin f1be242c95 integrity: digital signature config option name change
Similar to SIGNATURE, rename INTEGRITY_DIGSIG to INTEGRITY_SIGNATURE.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: James Morris <jmorris@namei.org>
2012-01-18 10:46:27 +11:00
Dmitry Kasatkin 5e8898e97a lib: digital signature config option name change
It was reported that DIGSIG is confusing name for digital signature
module. It was suggested to rename DIGSIG to SIGNATURE.

Requested-by: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: James Morris <jmorris@namei.org>
2012-01-18 10:46:21 +11:00
Kees Cook 41fdc3054e audit: treat s_id as an untrusted string
The use of s_id should go through the untrusted string path, just to be
extra careful.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:17:03 -05:00
James Morris 8fcc995495 Merge branch 'next' into for-linus
Conflicts:
	security/integrity/evm/evm_crypto.c

Resolved upstream fix vs. next conflict manually.

Signed-off-by: James Morris <jmorris@namei.org>
2012-01-09 12:16:48 +11:00
Dmitry Kasatkin 97426f9857 evm: prevent racing during tfm allocation
There is a small chance of racing during tfm allocation.
This patch fixes it.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-12-20 17:50:08 +02:00
Dmitry Kasatkin d21b594518 evm: key must be set once during initialization
On multi-core systems, setting of the key before every caclculation,
causes invalid HMAC calculation for other tfm users, because internal
state (ipad, opad) can be invalid before set key call returns.
It needs to be set only once during initialization.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-12-20 17:45:45 +02:00
Roberto Sassu 7b7e5916aa ima: fix invalid memory reference
Don't free a valid measurement entry on TPM PCR extend failure.

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Cc: stable@vger.kernel.org
2011-12-19 22:07:54 -05:00
Roberto Sassu 45fae74939 ima: free duplicate measurement memory
Info about new measurements are cached in the iint for performance.  When
the inode is flushed from cache, the associated iint is flushed as well.
Subsequent access to the inode will cause the inode to be re-measured and
will attempt to add a duplicate entry to the measurement list.

This patch frees the duplicate measurement memory, fixing a memory leak.

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Cc: stable@vger.kernel.org
2011-12-19 22:04:32 -05:00
Dmitry Kasatkin 143b01d332 evm: prevent racing during tfm allocation
There is a small chance of racing during tfm allocation.
This patch fixes it.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-12-08 10:06:12 +11:00
Dmitry Kasatkin 88d7ed3508 evm: key must be set once during initialization
On multi-core systems, setting of the key before every caclculation,
causes invalid HMAC calculation for other tfm users, because internal
state (ipad, opad) can be invalid before set key call returns.
It needs to be set only once during initialization.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-12-08 10:06:09 +11:00
Dmitry Kasatkin de35353375 digsig: build dependency fix
Fix build errors by adding Kconfig dependency on KEYS.
CRYPTO dependency removed.

  CC      security/integrity/digsig.o
security/integrity/digsig.c: In function ?integrity_digsig_verify?:
security/integrity/digsig.c:38:4: error: implicit declaration of function ?request_key?
security/integrity/digsig.c:38:17: error: ?key_type_keyring? undeclared (first use in this function)
security/integrity/digsig.c:38:17: note: each undeclared identifier is reported only once for each function it appears in
make[2]: *** [security/integrity/digsig.o] Error 1

Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-11-22 10:02:32 +11:00
Dmitry Kasatkin 15647eb398 evm: digital signature verification support
This patch adds support for digital signature verification to EVM.
With this feature file metadata can be protected using digital
signature instead of an HMAC. When building an image,
which has to be flashed to different devices, an HMAC cannot
be used to sign file metadata, because the HMAC key should be
different on every device.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
2011-11-09 16:51:14 +02:00
Dmitry Kasatkin 8607c50147 integrity: digital signature verification using multiple keyrings
Define separate keyrings for each of the different use cases - evm, ima,
and modules. Using different keyrings improves search performance, and also
allows "locking" specific keyring to prevent adding new keys.
This is useful for evm and module keyrings, when keys are usually only
added from initramfs.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
2011-11-09 16:51:09 +02:00
Linus Torvalds de0a5345a5 Merge branch 'for-linus' of git://github.com/richardweinberger/linux
* 'for-linus' of git://github.com/richardweinberger/linux: (90 commits)
  um: fix ubd cow size
  um: Fix kmalloc argument order in um/vdso/vma.c
  um: switch to use of drivers/Kconfig
  UserModeLinux-HOWTO.txt: fix a typo
  UserModeLinux-HOWTO.txt: remove ^H characters
  um: we need sys/user.h only on i386
  um: merge delay_{32,64}.c
  um: distribute exports to where exported stuff is defined
  um: kill system-um.h
  um: generic ftrace.h will do...
  um: segment.h is x86-only and needed only there
  um: asm/pda.h is not needed anymore
  um: hw_irq.h can go generic as well
  um: switch to generic-y
  um: clean Kconfig up a bit
  um: a couple of missing dependencies...
  um: kill useless argument of free_chan() and free_one_chan()
  um: unify ptrace_user.h
  um: unify KSTK_...
  um: fix gcov build breakage
  ...
2011-11-02 09:45:39 -07:00
Al Viro 3369465ed1 um: switch to use of drivers/Kconfig
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:41 +01:00
Dmitry Kasatkin fb788d8b98 evm: clean verification status
When allocating from slab, initialization is done the first time in
init_once() and subsequently on free.  Because evm_status was not
re-initialized on free, evm_verify_hmac() skipped verifications.

This patch re-initializes evm_status.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14 15:24:52 -04:00
Mimi Zohar 566be59ab8 evm: permit mode bits to be updated
Before permitting 'security.evm' to be updated, 'security.evm' must
exist and be valid.  In the case that there are no existing EVM protected
xattrs, it is safe for posix acls to update the mode bits.

To differentiate between no 'security.evm' xattr and no xattrs used to
calculate 'security.evm', this patch defines INTEGRITY_NOXATTR.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14 15:24:52 -04:00
Mimi Zohar bf6d0f5dcd evm: posix acls modify i_mode
The posix xattr acls are 'system' prefixed, which normally would not
affect security.evm.  An interesting side affect of writing posix xattr
acls is their modifying of the i_mode, which is included in security.evm.

This patch updates security.evm when posix xattr acls are written.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14 15:24:51 -04:00
Mimi Zohar a924ce0b35 evm: limit verifying current security.evm integrity
evm_protect_xattr unnecessarily validates the current security.evm
integrity, before updating non-evm protected extended attributes
and other file metadata. This patch limits validating the current
security.evm integrity to evm protected metadata.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14 15:24:51 -04:00