Commit graph

324 commits

Author SHA1 Message Date
Dmitry Kasatkin
11d7646df8 ima: provide buffer hash calculation function
This patch provides convenient buffer hash calculation function.

Changelog v3:
- fix while hash calculation - Dmitry
v1:
- rewrite to support loff_t sized buffers - Mimi
  (based on Fenguang Wu's testing)

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2016-02-18 17:14:28 -05:00
Mimi Zohar
4ad87a3d74 ima: use "ima_hooks" enum as function argument
Cleanup the function arguments by using "ima_hooks" enumerator as needed.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Petko Manolov <petkan@mip-labs.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
2016-02-18 17:13:58 -05:00
Mimi Zohar
b5269ab3e2 ima: refactor ima_policy_show() to display "ima_hooks" rules
Define and call a function to display the "ima_hooks" rules.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Petko Manolov <petkan@mip-labs.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
2016-02-18 17:13:56 -05:00
Dmitry Kasatkin
1525b06d99 ima: separate 'security.ima' reading functionality from collect
Instead of passing pointers to pointers to ima_collect_measurent() to
read and return the 'security.ima' xattr value, this patch moves the
functionality to the calling process_measurement() to directly read
the xattr and pass only the hash algo to the ima_collect_measurement().

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2016-02-18 17:13:32 -05:00
Colin Ian King
c75d8e96f3 IMA: fix non-ANSI declaration of ima_check_policy()
ima_check_policy() has no parameters, so use the normal void
parameter convention to make it match the prototype in the header file
security/integrity/ima/ima.h

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2016-02-08 18:17:38 -05:00
Al Viro
5955102c99 wrappers for ->i_mutex access
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 18:04:28 -05:00
Petko Manolov
6427e6c71c ima: ima_write_policy() limit locking
There is no need to hold the ima_write_mutex for so long.  We only need it
around ima_parse_add_rule().

Changelog:
- The return path now takes into account failed kmalloc() call.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Petko Manolov <petkan@mip-labs.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2016-01-03 13:22:38 -05:00
Sasha Levin
0112721df4 IMA: policy can be updated zero times
Commit "IMA: policy can now be updated multiple times" assumed that the
policy would be updated at least once.

If there are zero updates, the temporary list head object will get added
to the policy list, and later dereferenced as an IMA policy object, which
means that invalid memory will be accessed.

Changelog:
- Move list_empty() test to ima_release_policy(), before audit msg - Mimi

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-12-24 18:56:45 -05:00
Paul Gortmaker
92cc916638 security/integrity: make ima/ima_mok.c explicitly non-modular
The Kconfig currently controlling compilation of this code is:

ima/Kconfig:config IMA_MOK_KEYRING
ima/Kconfig: bool "Create IMA machine owner keys (MOK) and blacklist keyrings"

...meaning that it currently is not being built as a module by anyone.

Lets remove the couple of traces of modularity so that when reading the
driver there is no doubt it really is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: linux-ima-devel@lists.sourceforge.net
Cc: linux-ima-user@lists.sourceforge.net
Cc: linux-security-module@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-12-15 10:01:43 -05:00
Mimi Zohar
6ad6afa146 ima: update appraise flags after policy update completes
While creating a temporary list of new rules, the ima_appraise flag is
updated, but not reverted on failure to append the new rules to the
existing policy.  This patch defines temp_ima_appraise flag.  Only when
the new rules are appended to the policy is the flag updated.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Petko Manolov <petkan@mip-labs.com>
2015-12-15 10:01:43 -05:00
Mimi Zohar
501f1bde66 IMA: prevent keys on the .ima_blacklist from being removed
Set the KEY_FLAGS_KEEP on the .ima_blacklist to prevent userspace
from removing keys from the keyring.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-12-15 10:01:43 -05:00
Petko Manolov
80eae209d6 IMA: allow reading back the current IMA policy
It is often useful to be able to read back the IMA policy.  It is
even more important after introducing CONFIG_IMA_WRITE_POLICY.
This option allows the root user to see the current policy rules.

Signed-off-by: Zbigniew Jasinski <z.jasinski@samsung.com>
Signed-off-by: Petko Manolov <petkan@mip-labs.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-12-15 10:01:43 -05:00
Petko Manolov
41c89b64d7 IMA: create machine owner and blacklist keyrings
This option creates IMA MOK and blacklist keyrings.  IMA MOK is an
intermediate keyring that sits between .system and .ima keyrings,
effectively forming a simple CA hierarchy.  To successfully import a key
into .ima_mok it must be signed by a key which CA is in .system keyring.
On turn any key that needs to go in .ima keyring must be signed by CA in
either .system or .ima_mok keyrings. IMA MOK is empty at kernel boot.

IMA blacklist keyring contains all revoked IMA keys.  It is consulted
before any other keyring.  If the search is successful the requested
operation is rejected and error is returned to the caller.

Signed-off-by: Petko Manolov <petkan@mip-labs.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-12-15 10:01:43 -05:00
Petko Manolov
38d859f991 IMA: policy can now be updated multiple times
The new rules get appended to the original policy, forming a queue.
The new rules are first added to a temporary list, which on error
get released without disturbing the normal IMA operations.  On
success both lists (the current policy and the new rules) are spliced.

IMA policy reads are many orders of magnitude more numerous compared to
writes, the match code is RCU protected.  The updater side also does
list splice in RCU manner.

Signed-off-by: Petko Manolov <petkan@mip-labs.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-12-15 10:01:43 -05:00
Dmitry Kasatkin
f4dc37785e integrity: define '.evm' as a builtin 'trusted' keyring
Require all keys added to the EVM keyring be signed by an
existing trusted key on the system trusted keyring.

This patch also switches IMA to use integrity_init_keyring().

Changes in v3:
* Added 'init_keyring' config based variable to skip initializing
  keyring instead of using  __integrity_init_keyring() wrapper.
* Added dependency back to CONFIG_IMA_TRUSTED_KEYRING

Changes in v2:
* Replace CONFIG_EVM_TRUSTED_KEYRING with IMA and EVM common
  CONFIG_INTEGRITY_TRUSTED_KEYRING configuration option
* Deprecate CONFIG_IMA_TRUSTED_KEYRING but keep it for config
  file compatibility. (Mimi Zohar)

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-11-23 14:30:02 -05:00
Mel Gorman
71baba4b92 mm, page_alloc: rename __GFP_WAIT to __GFP_RECLAIM
__GFP_WAIT was used to signal that the caller was in atomic context and
could not sleep.  Now it is possible to distinguish between true atomic
context and callers that are not willing to sleep.  The latter should
clear __GFP_DIRECT_RECLAIM so kswapd will still wake.  As clearing
__GFP_WAIT behaves differently, there is a risk that people will clear the
wrong flags.  This patch renames __GFP_WAIT to __GFP_RECLAIM to clearly
indicate what it does -- setting it allows all reclaim activity, clearing
them prevents it.

[akpm@linux-foundation.org: fix build]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06 17:50:42 -08:00
Linus Torvalds
02201e3f1b Minor merge needed, due to function move.
Main excitement here is Peter Zijlstra's lockless rbtree optimization to
 speed module address lookup.  He found some abusers of the module lock
 doing that too.
 
 A little bit of parameter work here too; including Dan Streetman's breaking
 up the big param mutex so writing a parameter can load another module (yeah,
 really).  Unfortunately that broke the usual suspects, !CONFIG_MODULES and
 !CONFIG_SYSFS, so those fixes were appended too.
 
 Cheers,
 Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module updates from Rusty Russell:
 "Main excitement here is Peter Zijlstra's lockless rbtree optimization
  to speed module address lookup.  He found some abusers of the module
  lock doing that too.

  A little bit of parameter work here too; including Dan Streetman's
  breaking up the big param mutex so writing a parameter can load
  another module (yeah, really).  Unfortunately that broke the usual
  suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were
  appended too"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits)
  modules: only use mod->param_lock if CONFIG_MODULES
  param: fix module param locks when !CONFIG_SYSFS.
  rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()
  module: add per-module param_lock
  module: make perm const
  params: suppress unused variable error, warn once just in case code changes.
  modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'.
  kernel/module.c: avoid ifdefs for sig_enforce declaration
  kernel/workqueue.c: remove ifdefs over wq_power_efficient
  kernel/params.c: export param_ops_bool_enable_only
  kernel/params.c: generalize bool_enable_only
  kernel/module.c: use generic module param operaters for sig_enforce
  kernel/params: constify struct kernel_param_ops uses
  sysfs: tightened sysfs permission checks
  module: Rework module_addr_{min,max}
  module: Use __module_address() for module_address_lookup()
  module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING
  module: Optimize __module_address() using a latched RB-tree
  rbtree: Implement generic latch_tree
  seqlock: Introduce raw_read_seqcount_latch()
  ...
2015-07-01 10:49:25 -07:00
Mimi Zohar
24fd03c876 ima: update builtin policies
This patch defines a builtin measurement policy "tcb", similar to the
existing "ima_tcb", but with additional rules to also measure files
based on the effective uid and to measure files opened with the "read"
mode bit set (eg. read, read-write).

Changing the builtin "ima_tcb" policy could potentially break existing
users.  Instead of defining a new separate boot command line option each
time the builtin measurement policy is modified, this patch defines a
single generic boot command line option "ima_policy=" to specify the
builtin policy and deprecates the use of the builtin ima_tcb policy.

[The "ima_policy=" boot command line option is based on Roberto Sassu's
"ima: added new policy type exec" patch.]

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dr. Greg Wettstein <gw@idfusion.org>
Cc: stable@vger.kernel.org
2015-06-16 08:18:45 -04:00
Mimi Zohar
4351c294b8 ima: extend "mask" policy matching support
The current "mask" policy option matches files opened as MAY_READ,
MAY_WRITE, MAY_APPEND or MAY_EXEC.  This patch extends the "mask"
option to match files opened containing one of these modes.  For
example, "mask=^MAY_READ" would match files opened read-write.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dr. Greg Wettstein <gw@idfusion.org>
Cc: stable@vger.kernel.org
2015-06-16 08:18:44 -04:00
Mimi Zohar
139069eff7 ima: add support for new "euid" policy condition
The new "euid" policy condition measures files with the specified
effective uid (euid).  In addition, for CAP_SETUID files it measures
files with the specified uid or suid.

Changelog:
- fixed checkpatch.pl warnings
- fixed avc denied {setuid} messages - based on Roberto's feedback

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dr. Greg Wettstein <gw@idfusion.org>
Cc: stable@vger.kernel.org
2015-06-16 08:18:43 -04:00
Mimi Zohar
45b26133b9 ima: fix ima_show_template_data_ascii()
This patch fixes a bug introduced in "4d7aeee ima: define new template
ima-ng and template fields d-ng and n-ng".

Changelog:
- change int to uint32 (Roberto Sassu's suggestion)

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Roberto Sassu <rsassu@suse.de>
Cc: stable@vger.kernel.org # 3.13
2015-06-16 08:18:21 -04:00
Luis R. Rodriguez
9c27847dda kernel/params: constify struct kernel_param_ops uses
Most code already uses consts for the struct kernel_param_ops,
sweep the kernel for the last offending stragglers. Other than
include/linux/moduleparam.h and kernel/params.c all other changes
were generated with the following Coccinelle SmPL patch. Merge
conflicts between trees can be handled with Coccinelle.

In the future git could get Coccinelle merge support to deal with
patch --> fail --> grammar --> Coccinelle --> new patch conflicts
automatically for us on patches where the grammar is available and
the patch is of high confidence. Consider this a feature request.

Test compiled on x86_64 against:

	* allnoconfig
	* allmodconfig
	* allyesconfig

@ const_found @
identifier ops;
@@

const struct kernel_param_ops ops = {
};

@ const_not_found depends on !const_found @
identifier ops;
@@

-struct kernel_param_ops ops = {
+const struct kernel_param_ops ops = {
};

Generated-by: Coccinelle SmPL
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Junio C Hamano <gitster@pobox.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: cocci@systeme.lip6.fr
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-05-28 11:32:10 +09:30
Roberto Sassu
8d94eb9b5c ima: pass iint to ima_add_violation()
This patch adds the iint associated to the current inode as a new
parameter of ima_add_violation(). The passed iint is always not NULL
if a violation is detected. This modification will be used to determine
the inode for which there is a violation.

Since the 'd' and 'd-ng' template field init() functions were detecting
a violation from the value of the iint pointer, they now check the new
field 'violation', added to the 'ima_event_data' structure.

Changelog:
 - v1:
   - modified an old comment (Roberto Sassu)

Signed-off-by: Roberto Sassu <rsassu@suse.de>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-05-21 13:59:29 -04:00
Roberto Sassu
23b5741932 ima: wrap event related data to the new ima_event_data structure
All event related data has been wrapped into the new 'ima_event_data'
structure. The main benefit of this patch is that a new information
can be made available to template fields initialization functions
by simply adding a new field to the new structure instead of modifying
the definition of those functions.

Changelog:
 - v2:
   - f_dentry replaced with f_path.dentry (Roberto Sassu)
   - removed declaration of temporary variables in template field functions
     when possible (suggested by Dmitry Kasatkin)

Signed-off-by: Roberto Sassu <rsassu@suse.de>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-05-21 13:59:28 -04:00
Dmitry Kasatkin
a18d0cbfab ima: remove definition of IMA_X509_PATH
CONFIG_IMA_X509_PATH is always defined.  This patch removes the
IMA_X509_PATH definition and uses CONFIG_IMA_X509_PATH.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-05-21 13:28:47 -04:00
Dmitry Kasatkin
c68ed80c97 ima: limit file hash setting by user to fix and log modes
File hashes are automatically set and updated and should not be
manually set. This patch limits file hash setting to fix and log
modes.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-05-21 13:28:46 -04:00
Mimi Zohar
cd025f7f94 ima: do not measure or appraise the NSFS filesystem
Include don't appraise or measure rules for the NSFS filesystem
in the builtin ima_tcb and ima_appraise_tcb policies.

Changelog:
- Update documentation

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # 3.19
2015-05-21 13:28:41 -04:00
Roberto Sassu
6438de9f3f ima: skip measurement of cgroupfs files and update documentation
This patch adds a rule in the default measurement policy to skip inodes
in the cgroupfs filesystem. Measurements for this filesystem can be
avoided, as all the digests collected have the same value of the digest of
an empty file.

Furthermore, this patch updates the documentation of IMA policies in
Documentation/ABI/testing/ima_policy to make it consistent with
the policies set in security/integrity/ima/ima_policy.c.

Signed-off-by: Roberto Sassu <rsassu@suse.de>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-05-21 13:27:19 -04:00
Dan Carpenter
5577857f8e ima: cleanup ima_init_policy() a little
It's a bit easier to read this if we split it up into two for loops.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-05-13 06:07:19 -04:00
David Howells
c6f493d631 VFS: security/: d_backing_inode() annotations
most of the ->d_inode uses there refer to the same inode IO would
go to, i.e. d_backing_inode()

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:56 -04:00
David Howells
11cd64a234 ima: /proc/keys is now mandatory
/proc/keys is now mandatory and its config option no longer exists, so it
doesn't need selecting.

Reported-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-02-02 13:19:48 +11:00
James Morris
d0bffab043 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity into for-linus 2014-12-16 12:49:10 +11:00
Linus Torvalds
67e2c38838 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security layer updates from James Morris:
 "In terms of changes, there's general maintenance to the Smack,
  SELinux, and integrity code.

  The IMA code adds a new kconfig option, IMA_APPRAISE_SIGNED_INIT,
  which allows IMA appraisal to require signatures.  Support for reading
  keys from rootfs before init is call is also added"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (23 commits)
  selinux: Remove security_ops extern
  security: smack: fix out-of-bounds access in smk_parse_smack()
  VFS: refactor vfs_read()
  ima: require signature based appraisal
  integrity: provide a hook to load keys when rootfs is ready
  ima: load x509 certificate from the kernel
  integrity: provide a function to load x509 certificate from the kernel
  integrity: define a new function integrity_read_file()
  Security: smack: replace kzalloc with kmem_cache for inode_smack
  Smack: Lock mode for the floor and hat labels
  ima: added support for new kernel cmdline parameter ima_template_fmt
  ima: allocate field pointers array on demand in template_desc_init_fields()
  ima: don't allocate a copy of template_fmt in template_desc_init_fields()
  ima: display template format in meas. list if template name length is zero
  ima: added error messages to template-related functions
  ima: use atomic bit operations to protect policy update interface
  ima: ignore empty and with whitespaces policy lines
  ima: no need to allocate entry for comment
  ima: report policy load status
  ima: use path names cache
  ...
2014-12-14 20:36:37 -08:00
Al Viro
ba00410b81 Merge branch 'iov_iter' into for-next 2014-12-08 20:39:29 -05:00
Michael Ellerman
63a0eb7891 ima: Fix build failure on powerpc when TCG_IBMVTPM dependencies are not met
On powerpc we can end up with IMA=y and PPC_PSERIES=n which leads to:

 warning: (IMA) selects TCG_IBMVTPM which has unmet direct dependencies (TCG_TPM && PPC_PSERIES)
  tpm_ibmvtpm.c:(.text+0x14f3e8): undefined reference to `.plpar_hcall_norets'

I'm not sure why IMA needs to select those user-visible symbols, but if
it must then the simplest fix is to just express the proper dependencies
on the select.

Tested-by: Hon Ching (Vicky) Lo <lo1@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-12-06 21:50:37 -05:00
Al Viro
b583043e99 kill f_dentry uses
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-19 13:01:25 -05:00
Dmitry Kasatkin
c57782c13e ima: require signature based appraisal
This patch provides CONFIG_IMA_APPRAISE_SIGNED_INIT kernel configuration
option to force IMA appraisal using signatures. This is useful, when EVM
key is not initialized yet and we want securely initialize integrity or
any other functionality.

It forces embedded policy to require signature. Signed initialization
script can initialize EVM key, update the IMA policy and change further
requirement of everything to be signed.

Changes in v3:
* kernel parameter fixed to configuration option in the patch description

Changes in v2:
* policy change of this patch separated from the key loading patch

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-11-17 23:12:01 -05:00
Dmitry Kasatkin
fd5f4e9054 ima: load x509 certificate from the kernel
Define configuration option to load X509 certificate into the
IMA trusted kernel keyring. It implements ima_load_x509() hook
to load X509 certificate into the .ima trusted kernel keyring
from the root filesystem.

Changes in v3:
* use ima_policy_flag in ima_get_action()
  ima_load_x509 temporarily clears ima_policy_flag to disable
  appraisal to load key. Use it to skip appraisal rules.
* Key directory path changed to /etc/keys (Mimi)
* Expand IMA_LOAD_X509 Kconfig help

Changes in v2:
* added '__init'
* use ima_policy_flag to disable appraisal to load keys

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-11-17 23:12:00 -05:00
Dmitry Kasatkin
e3c4abbfa9 integrity: define a new function integrity_read_file()
This patch defines a new function called integrity_read_file()
to read file from the kernel into a buffer. Subsequent patches
will read a file containing the public keys and load them onto
the IMA keyring.

This patch moves and renames ima_kernel_read(), the non-security
checking version of kernel_read(), to integrity_kernel_read().

Changes in v3:
* Patch descriptions improved (Mimi)
* Add missing cast (kbuild test robot)

Changes in v2:
* configuration option removed
* function declared as '__init'

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-11-17 23:09:18 -05:00
James Morris
6c880ad51b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity into for-linus 2014-10-29 15:03:54 +11:00
Dmitry Kasatkin
a48fda9de9 ima: check xattr value length and type in the ima_inode_setxattr()
ima_inode_setxattr() can be called with no value. Function does not
check the length so that following command can be used to produce
kernel oops: setfattr -n security.ima FOO. This patch fixes it.

Changes in v3:
* for stable reverted "allow setting hash only in fix or log mode"
  It will be a separate patch.

Changes in v2:
* testing validity of xattr type
* allow setting hash only in fix or log mode (Mimi)

[  261.562522] BUG: unable to handle kernel NULL pointer dereference at           (null)
[  261.564109] IP: [<ffffffff812af272>] ima_inode_setxattr+0x3e/0x5a
[  261.564109] PGD 3112f067 PUD 42965067 PMD 0
[  261.564109] Oops: 0000 [#1] SMP
[  261.564109] Modules linked in: bridge stp llc evdev serio_raw i2c_piix4 button fuse
[  261.564109] CPU: 0 PID: 3299 Comm: setxattr Not tainted 3.16.0-kds+ #2924
[  261.564109] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  261.564109] task: ffff8800428c2430 ti: ffff880042be0000 task.ti: ffff880042be0000
[  261.564109] RIP: 0010:[<ffffffff812af272>]  [<ffffffff812af272>] ima_inode_setxattr+0x3e/0x5a
[  261.564109] RSP: 0018:ffff880042be3d50  EFLAGS: 00010246
[  261.564109] RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000015
[  261.564109] RDX: 0000001500000000 RSI: 0000000000000000 RDI: ffff8800375cc600
[  261.564109] RBP: ffff880042be3d68 R08: 0000000000000000 R09: 00000000004d6256
[  261.564109] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88002149ba00
[  261.564109] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[  261.564109] FS:  00007f6c1e219740(0000) GS:ffff88005da00000(0000) knlGS:0000000000000000
[  261.564109] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  261.564109] CR2: 0000000000000000 CR3: 000000003b35a000 CR4: 00000000000006f0
[  261.564109] Stack:
[  261.564109]  ffff88002149ba00 ffff880042be3df8 0000000000000000 ffff880042be3d98
[  261.564109]  ffffffff812a101b ffff88002149ba00 ffff880042be3df8 0000000000000000
[  261.564109]  0000000000000000 ffff880042be3de0 ffffffff8116d08a ffff880042be3dc8
[  261.564109] Call Trace:
[  261.564109]  [<ffffffff812a101b>] security_inode_setxattr+0x48/0x6a
[  261.564109]  [<ffffffff8116d08a>] vfs_setxattr+0x6b/0x9f
[  261.564109]  [<ffffffff8116d1e0>] setxattr+0x122/0x16c
[  261.564109]  [<ffffffff811687e8>] ? mnt_want_write+0x21/0x45
[  261.564109]  [<ffffffff8114d011>] ? __sb_start_write+0x10f/0x143
[  261.564109]  [<ffffffff811687e8>] ? mnt_want_write+0x21/0x45
[  261.564109]  [<ffffffff811687c0>] ? __mnt_want_write+0x48/0x4f
[  261.564109]  [<ffffffff8116d3e6>] SyS_setxattr+0x6e/0xb0
[  261.564109]  [<ffffffff81529da9>] system_call_fastpath+0x16/0x1b
[  261.564109] Code: 48 89 f7 48 c7 c6 58 36 81 81 53 31 db e8 73 27 04 00 85 c0 75 28 bf 15 00 00 00 e8 8a a5 d9 ff 84 c0 75 05 83 cb ff eb 15 31 f6 <41> 80 7d 00 03 49 8b 7c 24 68 40 0f 94 c6 e8 e1 f9 ff ff 89 d8
[  261.564109] RIP  [<ffffffff812af272>] ima_inode_setxattr+0x3e/0x5a
[  261.564109]  RSP <ffff880042be3d50>
[  261.564109] CR2: 0000000000000000
[  261.599998] ---[ end trace 39a89a3fc267e652 ]---

Reported-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-10-28 10:03:49 -04:00
Behan Webster
357aabed62 security, crypto: LLVMLinux: Remove VLAIS from ima_crypto.c
Replaced the use of a Variable Length Array In Struct (VLAIS) with a C99
compliant equivalent. This patch allocates the appropriate amount of memory
using a char array using the SHASH_DESC_ON_STACK macro.

The new code can be compiled with both gcc and clang.

Signed-off-by: Behan Webster <behanw@converseincode.com>
Reviewed-by: Mark Charlebois <charlebm@gmail.com>
Reviewed-by: Jan-Simon Möller <dl9pf@gmx.de>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Cc: tglx@linutronix.de
2014-10-14 10:51:24 +02:00
Roberto Sassu
c2426d2ad5 ima: added support for new kernel cmdline parameter ima_template_fmt
This patch allows users to provide a custom template format through the
new kernel command line parameter 'ima_template_fmt'. If the supplied
format is not valid, IMA uses the default template descriptor.

Changelog:
 - v3:
   - added check for 'fields' and 'num_fields' in
     template_desc_init_fields() (suggested by Mimi Zohar)

 - v2:
   - using template_desc_init_fields() to validate a format string
     (Roberto Sassu)
   - updated documentation by stating that only the chosen template
     descriptor is initialized (Roberto Sassu)

 - v1:
   - simplified code of ima_template_fmt_setup()
     (Roberto Sassu, suggested by Mimi Zohar)

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-10-13 08:39:02 -04:00
Roberto Sassu
1bd7face74 ima: allocate field pointers array on demand in template_desc_init_fields()
The allocation of a field pointers array is moved at the end of
template_desc_init_fields() and done only if the value of the 'fields'
and 'num_fields' parameters is not NULL. For just validating a template
format string, retrieved template field pointers are placed in a temporary
array.

Changelog:
 - v3:
   - do not check in this patch if 'fields' and 'num_fields' are NULL
     (suggested by Mimi Zohar)

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-10-13 08:39:02 -04:00
Roberto Sassu
9f3166b8ca ima: don't allocate a copy of template_fmt in template_desc_init_fields()
This patch removes the allocation of a copy of 'template_fmt', needed for
iterating over all fields in the passed template format string. The removal
was possible by replacing strcspn(), which modifies the passed string,
with strchrnul(). The currently processed template field is copied in
a temporary variable.

The purpose of this change is use template_desc_init_fields() in two ways:
for just validating a template format string (the function should work
if called by a setup function, when memory cannot be allocated), and for
actually initializing a template descriptor. The implementation of this
feature will be complete with the next patch.

Changelog:
 - v3:
   - added 'goto out' in template_desc_init_fields() to free allocated
     memory if a template field length is not valid (suggested by
     Mimi Zohar)

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-10-13 08:39:01 -04:00
Roberto Sassu
7dbdb4206b ima: display template format in meas. list if template name length is zero
With the introduction of the 'ima_template_fmt' kernel cmdline parameter,
a user can define a new template descriptor with custom format. However,
in this case, userspace tools will be unable to parse the measurements
list because the new template is unknown. For this reason, this patch
modifies the current IMA behavior to display in the list the template
format instead of the name (only if the length of the latter is zero)
so that a tool can extract needed information if it can handle listed
fields.

This patch also correctly displays the error log message in
ima_init_template() if the selected template cannot be initialized.

Changelog:
 - v3:
   - check the first byte of 'e->template_desc->name' instead of using
     strlen() in ima_fs.c (suggested by Mimi Zohar)

 - v2:
   - print the template format in ima_init_template(), if the selected
     template is custom (Roberto Sassu)

 - v1:
   - fixed patch description (Roberto Sassu, suggested by Mimi Zohar)
   - set 'template_name' variable in ima_fs.c only once
     (Roberto Sassu, suggested by Mimi Zohar)

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-10-13 08:39:01 -04:00
Roberto Sassu
71fed2eee0 ima: added error messages to template-related functions
This patch adds some error messages to inform users about the following
events: template descriptor not found, invalid template descriptor,
template field not found and template initialization failed.

Changelog:
 - v2:
   - display an error message if the format string contains too many
     fields (Roberto Sassu)

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-10-13 08:39:01 -04:00
Dmitry Kasatkin
0716abbb58 ima: use atomic bit operations to protect policy update interface
The current implementation uses an atomic counter to provide exclusive
access to the sysfs 'policy' entry to update the IMA policy. While it is
highly unlikely, the usage of a counter might potentially allow another
process to overflow the counter, open the interface and insert additional
rules into the policy being loaded.

This patch replaces using an atomic counter with atomic bit operations
which is more reliable and a widely used method to provide exclusive access.

As bit operation keep the interface locked after successful update, it makes
it unnecessary to verify if the default policy was set or not during parsing
and interface closing. This patch also removes that code.

Changes in v3:
* move audit log message to ima_relead_policy() to report successful and
  unsuccessful result
* unnecessary comment removed

Changes in v2:
* keep interface locked after successful policy load as in original design
* remove sysfs entry as in original design

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-10-11 23:33:02 -04:00
Dmitry Kasatkin
7178784f0a ima: ignore empty and with whitespaces policy lines
Empty policy lines cause parsing failures which is, especially
for new users, hard to spot. This patch prevents it.

Changes in v2:
* strip leading blanks and tabs in rules to prevent parsing failures

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-10-11 23:29:19 -04:00
Dmitry Kasatkin
272a6e90ff ima: no need to allocate entry for comment
If a rule is a comment, there is no need to allocate an entry.
Move the checking for comments before allocating the entry.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-10-11 23:28:07 -04:00
Dmitry Kasatkin
78bb5d0b4f ima: report policy load status
Audit messages are rate limited, often causing the policy update
info to not be visible.  Report policy loading status also using
pr_info.

Changes in v2:
* reporting moved to ima_release_policy to notice parsing errors
* reporting both completed and failed status

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-10-11 23:25:25 -04:00
Dmitry Kasatkin
456f5fd3f6 ima: use path names cache
__getname() uses slab allocation which is faster than kmalloc.
Make use of it.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-10-07 14:32:54 -04:00
Dmitry Kasatkin
0f34a0060a ima: check ima_policy_flag in the ima_file_free() hook
This patch completes the switching to the 'ima_policy_flag' variable
in the checks at the beginning of IMA functions, starting with the
commit a756024e.

Checking 'iint_initialized' is completely unnecessary, because
S_IMA flag is unset if iint was not allocated. At the same time
the integrity cache is allocated with SLAB_PANIC and the kernel will
panic if the allocation fails during kernel initialization. So on
a running system iint_initialized is always true and can be removed.

Changes in v3:
* not limiting test to IMA_APPRAISE (spotted by Roberto Sassu)

Changes in v2:
* 'iint_initialized' removal patch merged to this patch (requested
   by Mimi)

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Acked-by: Roberto Sassu <roberto.sassu@polito.it>
2014-10-07 14:32:52 -04:00
Roberto Sassu
1b68bdf9cd ima: detect violations for mmaped files
This patch fixes the detection of the 'open_writers' violation for mmaped
files.

before) an 'open_writers' violation is detected if the policy contains
        a rule with the criteria: func=FILE_CHECK mask=MAY_READ

after) an 'open_writers' violation is detected if the current event
       matches one of the policy rules.

With the old behaviour, the 'open_writers' violation is not detected
in the following case:

policy:
measure func=FILE_MMAP mask=MAY_EXEC

steps:
1) open a shared library for writing
2) execute a binary that links that shared library
3) during the binary execution, modify the shared library and save
   the change

result:
the 'open_writers' violation measurement is not present in the IMA list.

Only binaries executed are protected from writes. For libraries mapped
in memory there is the flag MAP_DENYWRITE for this purpose, but according
to the output of 'man mmap', the mmap flag is ignored.

Since ima_rdwr_violation_check() is now called by process_measurement()
the information about if the inode must be measured is already provided
by ima_get_action(). Thus the unnecessary function ima_must_measure()
has been removed.

Changes in v3 (Dmitry Kasatkin):
- Violation for MMAP_CHECK function are verified since this patch
- Changed patch description a bit

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-18 10:04:12 -04:00
Roberto Sassu
f7a859ff73 ima: fix race condition on ima_rdwr_violation_check and process_measurement
This patch fixes a race condition between two functions that try to access
the same inode. Since the i_mutex lock is held and released separately
in the two functions, there may be the possibility that a violation is
not correctly detected.

Suppose there are two processes, A (reader) and B (writer), if the
following sequence happens:

A: ima_rdwr_violation_check()
B: ima_rdwr_violation_check()
B: process_measurement()
B: starts writing the inode
A: process_measurement()

the ToMToU violation (a reader may be accessing a content different from
that measured, due to a concurrent modification by a writer) will not be
detected. To avoid this issue, the violation check and the measurement
must be done atomically.

This patch fixes the problem by moving the violation check inside
process_measurement() when the i_mutex lock is held. Differently from
the old code, the violation check is executed also for the MMAP_CHECK
hook (other than for FILE_CHECK). This allows to detect ToMToU violations
that are possible because shared libraries can be opened for writing
while they are in use (according to the output of 'man mmap', the mmap()
flag MAP_DENYWRITE is ignored).

Changes in v5 (Roberto Sassu):
* get iint if action is not zero
* exit process_measurement() after the violation check if action is zero
* reverse order process_measurement() exit cleanup (Mimi)

Changes in v4 (Dmitry Kasatkin):
* iint allocation is done before calling ima_rdrw_violation_check()
  (Suggested-by Mimi)
* do not check for violations if the policy does not contain 'measure'
  rules (done by Roberto Sassu)

Changes in v3 (Dmitry Kasatkin):
* no violation checking for MMAP_CHECK function in this patch
* remove use of filename from violation
* removes checking if ima is enabled from ima_rdrw_violation_check
* slight style change

Suggested-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-18 10:03:55 -04:00
Roberto Sassu
a756024efe ima: added ima_policy_flag variable
This patch introduces the new variable 'ima_policy_flag', whose bits
are set depending on the action of the current policy rules. Only the
flags IMA_MEASURE, IMA_APPRAISE and IMA_AUDIT are set.

The new variable will be used to improve performance by skipping the
unnecessary execution of IMA code if the policy does not contain rules
with the above actions.

Changes in v6 (Roberto Sassu)
* do not check 'ima_initialized' before calling ima_update_policy_flag()
  in ima_update_policy() (suggested by Dmitry)
* calling ima_update_policy_flag() moved to init_ima to co-locate with
  ima_initialized (Dmitry)
* add/revise comments (Mimi)

Changes in v5 (Roberto Sassu)
* reset IMA_APPRAISE flag in 'ima_policy_flag' if 'ima_appraise' is set
  to zero (reported by Dmitry)
* update 'ima_policy_flag' only if IMA initialization is successful
  (suggested by Mimi and Dmitry)
* check 'ima_policy_flag' instead of 'ima_initialized'
  (suggested by Mimi and Dmitry)

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-17 16:39:36 -04:00
Roberto Sassu
be39ffc2fe ima: return an error code from ima_add_boot_aggregate()
This patch modifies ima_add_boot_aggregate() to return an error code.
This way we can determine if all the initialization procedures have
been executed successfully.

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-17 16:15:42 -04:00
Dmitry Kasatkin
2faa6ef3b2 ima: provide 'ima_appraise=log' kernel option
The kernel boot parameter "ima_appraise" currently defines 'off',
'enforce' and 'fix' modes.  When designing a policy and labeling
the system, access to files are either blocked in the default
'enforce' mode or automatically fixed in the 'fix' mode.  It is
beneficial to be able to run the system in a logging only mode,
without fixing it, in order to properly analyze the system. This
patch adds a 'log' mode to run the system in a permissive mode and
log the appraisal results.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-17 16:14:23 -04:00
Dmitry Kasatkin
31b70f6632 ima: move keyring initialization to ima_init()
ima_init() is used as a single place for all initializations.
Experimental keyring patches used the 'late_initcall' which was
co-located with the late_initcall(init_ima). When the late_initcall
for the keyring initialization was abandoned, initialization moved
to init_ima, though it would be more logical to move it to ima_init,
where the rest of the initialization is done. This patch moves the
keyring initialization to ima_init() as a preparatory step for
loading the keys which will be added to ima_init() in following
patches.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-17 16:10:59 -04:00
Dmitry Kasatkin
7ef84e65ec integrity: base integrity subsystem kconfig options on integrity
The integrity subsystem has lots of options and takes more than
half of the security menu.  This patch consolidates the options
under "integrity", which are hidden if not enabled.  This change
does not affect existing configurations.  Re-configuration is not
needed.

Changes v4:
- no need to change "integrity subsystem" to menuconfig as
options are hidden, when not enabled. (Mimi)
- add INTEGRITY Kconfig help description

Changes v3:
- dependency to INTEGRITY removed when behind 'if INTEGRITY'

Changes v2:
- previous patch moved integrity out of the 'security' menu.
  This version keeps integrity as a security option (Mimi).

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-09 10:28:56 -04:00
Dmitry Kasatkin
b4148db517 ima: initialize only required template
IMA uses only one template. This patch initializes only required
template to avoid unnecessary memory allocations.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Reviewed-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-09 10:28:54 -04:00
Dmitry Kasatkin
17f4bad3ab ima: remove usage of filename parameter
In all cases except ima_bprm_check() the filename was not defined
and ima_d_path() was used to find the full path.  Unfortunately,
the bprm filename is a relative pathname (eg. ./<dir>/filename).

ima_bprm_check() selects between bprm->interp and bprm->filename.
The following dump demonstrates the differences between using
filename and interp.

bprm->filename
 filename: ./foo.sh, pathname: /root/bin/foo.sh
 filename: ./foo.sh, pathname: /bin/dash

bprm->interp
 filename: ./foo.sh, pathname: /root/bin/foo.sh
 filename: /bin/sh, pathname: /bin/dash

In both cases the pathnames are currently the same.  This patch
removes usage of filename and interp in favor of d_absolute_path.

Changes v3:
- 11 extra bytes for "deleted" not needed (Mimi)
- purpose "replace relative bprm filename with full pathname" (Mimi)

Changes v2:
- use d_absolute_path() instead of d_path to work in chroot environments.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-09 10:28:52 -04:00
Dmitry Kasatkin
86f2bc0249 ima: remove unnecessary appraisal test
ima_get_action() sets the "action" flags based on policy.
Before collecting, measuring, appraising, or auditing the
file, the "action" flag is updated based on the cached
iint->flags.

This patch removes the subsequent unnecessary appraisal
test in ima_appraise_measurement().

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-09 10:28:51 -04:00
Dmitry Kasatkin
e4a9c51965 ima: add missing '__init' keywords
Add missing keywords to the function definition to cleanup
to discard initialization code.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Reviewed-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-09 10:28:50 -04:00
Dmitry Kasatkin
3a8a2eadc4 ima: remove unnecessary extra variable
'function' variable value can be changed instead of
allocating extra '_func' variable.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-09 10:28:48 -04:00
Dmitry Kasatkin
f68c05f4d2 ima: simplify conditional statement to improve performance
Precede bit testing before string comparison makes code
faster. Also refactor statement as a single line pointer
assignment. Logic is following: we set 'xattr_ptr' to read
xattr value when we will do appraisal or in any case when
measurement template is other than 'ima'.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-09 10:28:47 -04:00
Dmitry Kasatkin
65d98f3be2 integrity: remove declaration of non-existing functions
Commit f381c27 "integrity: move ima inode integrity data management"
(re)moved few functions but left their declarations in header files.
This patch removes them and also removes duplicated declaration of
integrity_iint_find().

Commit c7de7ad "ima: remove unused cleanup functions".  This patch
removes these definitions as well.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-09 10:28:46 -04:00
Dmitry Kasatkin
3034a14682 ima: pass 'opened' flag to identify newly created files
Empty files and missing xattrs do not guarantee that a file was
just created.  This patch passes FILE_CREATED flag to IMA to
reliably identify new files.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>  3.14+
2014-09-09 10:28:43 -04:00
Dmitry Kasatkin
b151d6b00b ima: provide flag to identify new empty files
On ima_file_free(), newly created empty files are not labeled with
an initial security.ima value, because the iversion did not change.
Commit dff6efc "fs: fix iversion handling" introduced a change in
iversion behavior.  To verify this change use the shell command:

  $ (exec >foo)
  $ getfattr -h -e hex -d -m security foo

This patch defines the IMA_NEW_FILE flag.  The flag is initially
set, when IMA detects that a new file is created, and subsequently
checked on the ima_file_free() hook to set the initial security.ima
value.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>  3.14+
2014-09-08 17:38:57 -04:00
Dmitry Kasatkin
27cd1fc3ae ima: fix fallback to use new_sync_read()
3.16 commit aad4f8bb42
'switch simple generic_file_aio_read() users to ->read_iter()'
replaced ->aio_read with ->read_iter in most of the file systems
and introduced new_sync_read() as a replacement for do_sync_read().

Most of file systems set '->read' and ima_kernel_read is not affected.
When ->read is not set, this patch adopts fallback call changes from the
vfs_read.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>  3.16+
2014-09-02 17:03:36 -04:00
Dmitry Kasatkin
23c19e2ca7 ima: prevent buffer overflow in ima_alloc_tfm()
This patch fixes the case where the file's signature/hash xattr contains
an invalid hash algorithm.  Although we can not verify the xattr, we still
need to measure the file.  Use the default IMA hash algorithm.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-02 17:03:36 -04:00
Mimi Zohar
9a8d289fbc ima: fix ima_alloc_atfm()
The patch 3bcced39ea: "ima: use ahash API for file hash
calculation" from Feb 26, 2014, leads to the following static checker
warning:

security/integrity/ima/ima_crypto.c:204 ima_alloc_atfm()
         error: buffer overflow 'hash_algo_name' 17 <= 17

Unlike shash tfm memory, which is allocated on initialization, the
ahash tfm memory allocation is deferred until needed.

This patch fixes the case where ima_ahash_tfm has not yet been
allocated and the file's signature/hash xattr contains an invalid hash
algorithm.  Although we can not verify the xattr, we still need to
measure the file.  Use the default IMA hash algorithm.

Changelog:
- set valid algo before testing tfm - based on Dmitry's comment

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
2014-09-02 17:03:35 -04:00
Mimi Zohar
5a9196d715 ima: add support for measuring and appraising firmware
The "security: introduce kernel_fw_from_file hook" patch defined a
new security hook to evaluate any loaded firmware that wasn't built
into the kernel.

This patch defines ima_fw_from_file(), which is called from the new
security hook, to measure and/or appraise the loaded firmware's
integrity.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2014-07-25 11:47:46 -07:00
Mimi Zohar
7d2ce2320e ima: define '.ima' as a builtin 'trusted' keyring
Require all keys added to the IMA keyring be signed by an
existing trusted key on the system trusted keyring.

Changelog v6:
- remove ifdef CONFIG_IMA_TRUSTED_KEYRING in C code - Dmitry
- update Kconfig dependency and help
- select KEYS_DEBUG_PROC_KEYS - Dmitry

Changelog v5:
- Move integrity_init_keyring() to init_ima() - Dmitry
- reset keyring[id] on failure - Dmitry

Changelog v1:
- don't link IMA trusted keyring to user 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)
- only make the IMA keyring a trusted keyring (reported-by D. Kastatkin)
- define stub integrity_init_keyring() definition based on
  CONFIG_INTEGRITY_SIGNATURE, not CONFIG_INTEGRITY_ASYMMETRIC_KEYS.
  (reported-by Jim Davis)

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Acked-by: David Howells <dhowells@redhat.com>
2014-07-17 09:35:17 -04:00
Dmitry Kasatkin
32c2e6752f ima: provide double buffering for hash calculation
The asynchronous hash API allows initiating a hash calculation and
then performing other tasks, while waiting for the hash calculation
to complete.

This patch introduces usage of double buffering for simultaneous
hashing and reading of the next chunk of data from storage.

Changes in v3:
- better comments

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-17 09:35:11 -04:00
Dmitry Kasatkin
6edf7a8926 ima: introduce multi-page collect buffers
Use of multiple-page collect buffers reduces:
1) the number of block IO requests
2) the number of asynchronous hash update requests

Second is important for HW accelerated hashing, because significant
amount of time is spent for preparation of hash update operation,
which includes configuring acceleration HW, DMA engine, etc...
Thus, HW accelerators are more efficient when working on large
chunks of data.

This patch introduces usage of multi-page collect buffers. Buffer size
can be specified using 'ahash_bufsize' module parameter. Default buffer
size is 4096 bytes.

Changes in v3:
- kernel parameter replaced with module parameter

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-17 09:35:11 -04:00
Dmitry Kasatkin
3bcced39ea ima: use ahash API for file hash calculation
Async hash API allows the use of HW acceleration for hash calculation.
It may give significant performance gain and/or reduce power consumption,
which might be very beneficial for battery powered devices.

This patch introduces hash calculation using ahash API. ahash performance
depends on the data size and the particular HW. Depending on the specific
system, shash performance may be better.

This patch defines 'ahash_minsize' module parameter, which is used to
define the minimal file size to use with ahash.  If this minimum file size
is not set or the file is smaller than defined by the parameter, shash will
be used.

Changes in v3:
- kernel parameter replaced with module parameter
- pr_crit replaced with pr_crit_ratelimited
- more comment changes - Mimi

Changes in v2:
- ima_ahash_size became as ima_ahash
- ahash pre-allocation moved out from __init code to be able to use
  ahash crypto modules. Ahash allocated once on the first use.
- hash calculation falls back to shash if ahash allocation/calculation fails
- complex initialization separated from variable declaration
- improved comments

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-17 09:35:10 -04:00
Richard Guy Briggs
7e9001f663 audit: fix dangling keywords in integrity ima message output
Replace spaces in op keyword labels in log output since userspace audit tools
can't parse orphaned keywords.

Reported-by: Steve Grubb <sgrubb@redhat.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-17 09:35:10 -04:00
Dmitry Kasatkin
209b43ca64 ima: delay template descriptor lookup until use
process_measurement() always calls ima_template_desc_current(),
including when an IMA policy has not been defined.

This patch delays template descriptor lookup until action is
determined.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-17 09:35:09 -04:00
Dmitry Kasatkin
2c50b96482 ima: remove unnecessary i_mutex locking from ima_rdwr_violation_check()
Before 2.6.39 inode->i_readcount was maintained by IMA. It was not atomic
and protected using spinlock. For 2.6.39, i_readcount was converted to
atomic and maintaining was moved VFS layer. Spinlock for some unclear
reason was replaced by i_mutex.

After analyzing the code, we came to conclusion that i_mutex locking is
unnecessary, especially when an IMA policy has not been defined.

This patch removes i_mutex locking from ima_rdwr_violation_check().

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-17 09:35:09 -04:00
Dmitry Kasatkin
0430e49b6e ima: introduce ima_kernel_read()
Commit 8aac62706 "move exit_task_namespaces() outside of exit_notify"
introduced the kernel opps since the kernel v3.10, which happens when
Apparmor and IMA-appraisal are enabled at the same time.

----------------------------------------------------------------------
[  106.750167] BUG: unable to handle kernel NULL pointer dereference at
0000000000000018
[  106.750221] IP: [<ffffffff811ec7da>] our_mnt+0x1a/0x30
[  106.750241] PGD 0
[  106.750254] Oops: 0000 [#1] SMP
[  106.750272] Modules linked in: cuse parport_pc ppdev bnep rfcomm
bluetooth rpcsec_gss_krb5 nfsd auth_rpcgss nfs_acl nfs lockd sunrpc
fscache dm_crypt intel_rapl x86_pkg_temp_thermal intel_powerclamp
kvm_intel snd_hda_codec_hdmi kvm crct10dif_pclmul crc32_pclmul
ghash_clmulni_intel aesni_intel aes_x86_64 glue_helper lrw gf128mul
ablk_helper cryptd snd_hda_codec_realtek dcdbas snd_hda_intel
snd_hda_codec snd_hwdep snd_pcm snd_page_alloc snd_seq_midi
snd_seq_midi_event snd_rawmidi psmouse snd_seq microcode serio_raw
snd_timer snd_seq_device snd soundcore video lpc_ich coretemp mac_hid lp
parport mei_me mei nbd hid_generic e1000e usbhid ahci ptp hid libahci
pps_core
[  106.750658] CPU: 6 PID: 1394 Comm: mysqld Not tainted 3.13.0-rc7-kds+ #15
[  106.750673] Hardware name: Dell Inc. OptiPlex 9010/0M9KCM, BIOS A08
09/19/2012
[  106.750689] task: ffff8800de804920 ti: ffff880400fca000 task.ti:
ffff880400fca000
[  106.750704] RIP: 0010:[<ffffffff811ec7da>]  [<ffffffff811ec7da>]
our_mnt+0x1a/0x30
[  106.750725] RSP: 0018:ffff880400fcba60  EFLAGS: 00010286
[  106.750738] RAX: 0000000000000000 RBX: 0000000000000100 RCX:
ffff8800d51523e7
[  106.750764] RDX: ffffffffffffffea RSI: ffff880400fcba34 RDI:
ffff880402d20020
[  106.750791] RBP: ffff880400fcbae0 R08: 0000000000000000 R09:
0000000000000001
[  106.750817] R10: 0000000000000000 R11: 0000000000000001 R12:
ffff8800d5152300
[  106.750844] R13: ffff8803eb8df510 R14: ffff880400fcbb28 R15:
ffff8800d51523e7
[  106.750871] FS:  0000000000000000(0000) GS:ffff88040d200000(0000)
knlGS:0000000000000000
[  106.750910] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  106.750935] CR2: 0000000000000018 CR3: 0000000001c0e000 CR4:
00000000001407e0
[  106.750962] Stack:
[  106.750981]  ffffffff813434eb ffff880400fcbb20 ffff880400fcbb18
0000000000000000
[  106.751037]  ffff8800de804920 ffffffff8101b9b9 0001800000000000
0000000000000100
[  106.751093]  0000010000000000 0000000000000002 000000000000000e
ffff8803eb8df500
[  106.751149] Call Trace:
[  106.751172]  [<ffffffff813434eb>] ? aa_path_name+0x2ab/0x430
[  106.751199]  [<ffffffff8101b9b9>] ? sched_clock+0x9/0x10
[  106.751225]  [<ffffffff8134a68d>] aa_path_perm+0x7d/0x170
[  106.751250]  [<ffffffff8101b945>] ? native_sched_clock+0x15/0x80
[  106.751276]  [<ffffffff8134aa73>] aa_file_perm+0x33/0x40
[  106.751301]  [<ffffffff81348c5e>] common_file_perm+0x8e/0xb0
[  106.751327]  [<ffffffff81348d78>] apparmor_file_permission+0x18/0x20
[  106.751355]  [<ffffffff8130c853>] security_file_permission+0x23/0xa0
[  106.751382]  [<ffffffff811c77a2>] rw_verify_area+0x52/0xe0
[  106.751407]  [<ffffffff811c789d>] vfs_read+0x6d/0x170
[  106.751432]  [<ffffffff811cda31>] kernel_read+0x41/0x60
[  106.751457]  [<ffffffff8134fd45>] ima_calc_file_hash+0x225/0x280
[  106.751483]  [<ffffffff8134fb52>] ? ima_calc_file_hash+0x32/0x280
[  106.751509]  [<ffffffff8135022d>] ima_collect_measurement+0x9d/0x160
[  106.751536]  [<ffffffff810b552d>] ? trace_hardirqs_on+0xd/0x10
[  106.751562]  [<ffffffff8134f07c>] ? ima_file_free+0x6c/0xd0
[  106.751587]  [<ffffffff81352824>] ima_update_xattr+0x34/0x60
[  106.751612]  [<ffffffff8134f0d0>] ima_file_free+0xc0/0xd0
[  106.751637]  [<ffffffff811c9635>] __fput+0xd5/0x300
[  106.751662]  [<ffffffff811c98ae>] ____fput+0xe/0x10
[  106.751687]  [<ffffffff81086774>] task_work_run+0xc4/0xe0
[  106.751712]  [<ffffffff81066fad>] do_exit+0x2bd/0xa90
[  106.751738]  [<ffffffff8173c958>] ? retint_swapgs+0x13/0x1b
[  106.751763]  [<ffffffff8106780c>] do_group_exit+0x4c/0xc0
[  106.751788]  [<ffffffff81067894>] SyS_exit_group+0x14/0x20
[  106.751814]  [<ffffffff8174522d>] system_call_fastpath+0x1a/0x1f
[  106.751839] Code: c3 0f 1f 44 00 00 55 48 89 e5 e8 22 fe ff ff 5d c3
0f 1f 44 00 00 55 65 48 8b 04 25 c0 c9 00 00 48 8b 80 28 06 00 00 48 89
e5 5d <48> 8b 40 18 48 39 87 c0 00 00 00 0f 94 c0 c3 0f 1f 80 00 00 00
[  106.752185] RIP  [<ffffffff811ec7da>] our_mnt+0x1a/0x30
[  106.752214]  RSP <ffff880400fcba60>
[  106.752236] CR2: 0000000000000018
[  106.752258] ---[ end trace 3c520748b4732721 ]---
----------------------------------------------------------------------

The reason for the oops is that IMA-appraisal uses "kernel_read()" when
file is closed. kernel_read() honors LSM security hook which calls
Apparmor handler, which uses current->nsproxy->mnt_ns. The 'guilty'
commit changed the order of cleanup code so that nsproxy->mnt_ns was
not already available for Apparmor.

Discussion about the issue with Al Viro and Eric W. Biederman suggested
that kernel_read() is too high-level for IMA. Another issue, except
security checking, that was identified is mandatory locking. kernel_read
honors it as well and it might prevent IMA from calculating necessary hash.
It was suggested to use simplified version of the function without security
and locking checks.

This patch introduces special version ima_kernel_read(), which skips security
and mandatory locking checking. It prevents the kernel oops to happen.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Suggested-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
2014-06-12 17:58:08 -04:00
Dmitry Kasatkin
14503eb994 ima: check inode integrity cache in violation check
When IMA did not support ima-appraisal, existance of the S_IMA flag
clearly indicated that the file was measured. With IMA appraisal S_IMA
flag indicates that file was measured and/or appraised. Because of
this, when measurement is not enabled by the policy, violations are
still reported.

To differentiate between measurement and appraisal policies this
patch checks the inode integrity cache flags.  The IMA_MEASURED
flag indicates whether the file was actually measured, while the
IMA_MEASURE flag indicates whether the file should be measured.
Unfortunately, the IMA_MEASURED flag is reset to indicate the file
needs to be re-measured.  Thus, this patch checks the IMA_MEASURE
flag.

This patch limits the false positive violation reports, but does
not fix it entirely.  The IMA_MEASURE/IMA_MEASURED flags are
indications that, at some point in time, the file opened for read
was in policy, but might not be in policy now (eg. different uid).
Other changes would be needed to further limit false positive
violation reports.

Changelog:
- expanded patch description based on conversation with Roberto (Mimi)

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-06-12 17:58:07 -04:00
Dmitry Kasatkin
b882fae2d3 ima: prevent unnecessary policy checking
ima_rdwr_violation_check is called for every file openning.
The function checks the policy even when violation condition
is not met. It causes unnecessary policy checking.

This patch does policy checking only if violation condition is met.

Changelog:
- check writecount is greater than zero (Mimi)

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-06-12 17:58:06 -04:00
Mimi Zohar
060bdebfb0 ima: prevent new digsig xattr from being replaced
Even though a new xattr will only be appraised on the next access,
set the DIGSIG flag to prevent a signature from being replaced with
a hash on file close.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-06-12 17:58:05 -04:00
Mimi Zohar
f9b2a735bd ima: audit log files opened with O_DIRECT flag
Files are measured or appraised based on the IMA policy.  When a
file, in policy, is opened with the O_DIRECT flag, a deadlock
occurs.

The first attempt at resolving this lockdep temporarily removed the
O_DIRECT flag and restored it, after calculating the hash.  The
second attempt introduced the O_DIRECT_HAVELOCK flag. Based on this
flag, do_blockdev_direct_IO() would skip taking the i_mutex a second
time.  The third attempt, by Dmitry Kasatkin, resolves the i_mutex
locking issue, by re-introducing the IMA mutex, but uncovered
another problem.  Reading a file with O_DIRECT flag set, writes
directly to userspace pages.  A second patch allocates a user-space
like memory.  This works for all IMA hooks, except ima_file_free(),
which is called on __fput() to recalculate the file hash.

Until this last issue is addressed, do not 'collect' the
measurement for measuring, appraising, or auditing files opened
with the O_DIRECT flag set.  Based on policy, permit or deny file
access.  This patch defines a new IMA policy rule option named
'permit_directio'.  Policy rules could be defined, based on LSM
or other criteria, to permit specific applications to open files
with the O_DIRECT flag set.

Changelog v1:
- permit or deny file access based IMA policy rules

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Cc: <stable@vger.kernel.org>
2014-06-03 14:21:50 -05:00
Dmitry Kasatkin
1d91ac6213 ima: skip memory allocation for empty files
Memory allocation is unnecessary for empty files.
This patch calculates the hash without memory allocation.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-03-07 12:15:48 -05:00
Dmitry Kasatkin
61997c4383 ima: return d_name.name if d_path fails
This is a small refactoring so ima_d_path() returns dentry name
if path reconstruction fails. It simplifies callers actions
and removes code duplication.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-03-07 12:15:46 -05:00
Dmitry Kasatkin
2bb930abcf integrity: fix checkpatch errors
Between checkpatch changes (eg. sizeof) and inconsistencies between
Lindent and checkpatch, unfixed checkpatch errors make it difficult
to see new errors. This patch fixes them. Some lines with over 80 chars
remained unchanged to improve code readability.

The "extern" keyword is removed from internal evm.h to make it consistent
with internal ima.h.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-03-07 12:15:45 -05:00
Dmitry Kasatkin
09b1148ef5 ima: fix erroneous removal of security.ima xattr
ima_inode_post_setattr() calls ima_must_appraise() to check if the
file needs to be appraised. If it does not then it removes security.ima
xattr. With original policy matching code it might happen that even
file needs to be appraised with FILE_CHECK hook, it might not be
for POST_SETATTR hook. 'security.ima' might be erronously removed.

This patch treats POST_SETATTR as special wildcard function and will
cause ima_must_appraise() to be true if any of the hooks rules matches.
security.ima will not be removed if any of the hooks would require
appraisal.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-03-07 12:15:44 -05:00
Joe Perches
20ee451f5a security: integrity: Use a more current logging style
Convert printks to pr_<level>.
Add pr_fmt.
Remove embedded prefixes.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-03-07 12:15:21 -05:00
Roberto Sassu
e3b64c268b ima: reduce memory usage when a template containing the n field is used
Before this change, to correctly calculate the template digest for the
'ima' template, the event name field (id: 'n') length was set to the fixed
size of 256 bytes.

This patch reduces the length of the event name field to the string
length incremented of one (to make room for the termination character '\0')
and handles the specific case of the digest calculation for the 'ima'
template directly in ima_calc_field_array_hash_tfm().

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-03-07 11:32:30 -05:00
Roberto Sassu
c019e307ad ima: restore the original behavior for sending data with ima template
With the new template mechanism introduced in IMA since kernel 3.13,
the format of data sent through the binary_runtime_measurements interface
is slightly changed. Now, for a generic measurement, the format of
template data (after the template name) is:

template_len | field1_len | field1 | ... | fieldN_len | fieldN

In addition, fields containing a string now include the '\0' termination
character.

Instead, the format for the 'ima' template should be:

SHA1 digest | event name length | event name

It must be noted that while in the IMA 3.13 code 'event name length' is
'IMA_EVENT_NAME_LEN_MAX + 1' (256 bytes), so that the template digest
is calculated correctly, and 'event name' contains '\0', in the pre 3.13
code 'event name length' is exactly the string length and 'event name'
does not contain the termination character.

The patch restores the behavior of the IMA code pre 3.13 for the 'ima'
template so that legacy userspace tools obtain a consistent behavior
when receiving data from the binary_runtime_measurements interface
regardless of which kernel version is used.

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Cc: <stable@vger.kernel.org> # 3.3.13: 3ce1217 ima: define template fields library
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-03-07 11:32:29 -05:00
Mimi Zohar
52a1328484 ima: use static const char array definitions
A const char pointer allocates memory for a pointer as well as for
a string,  This patch replaces a number of the const char pointers
throughout IMA, with a static const char array.

Suggested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
2014-03-07 11:30:36 -05:00
Libo Chen
31d4b76189 ima: new helper: file_inode(file)
Replace "file->f_dentry->d_inode" with the new file_inode() helper
function.

Signed-off-by: Libo Chen <clbchenlibo.chen@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-03-04 16:53:03 -05:00
Jingoo Han
29707b206c security: replace strict_strto*() with kstrto*()
The usage of strict_strto*() is not preferred, because
strict_strto*() is obsolete. Thus, kstrto*() should be
used.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2014-02-06 19:11:04 +11:00
James Morris
38fd2c202a Merge to v3.13-rc7 for prerequisite changes in the Xen code for TPM 2014-01-06 22:23:01 +11:00
Roberto Sassu
dcf4e39286 ima: remove unneeded size_limit argument from ima_eventdigest_init_common()
This patch removes the 'size_limit' argument from
ima_eventdigest_init_common(). Since the 'd' field will never include
the hash algorithm as prefix and the 'd-ng' will always have it, we can
use the hash algorithm to differentiate the two cases in the modified
function (it is equal to HASH_ALGO__LAST in the first case, the opposite
in the second).

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-01-03 07:43:00 -05:00
Roberto Sassu
712a49bd7d ima: pass HASH_ALGO__LAST as hash algo in ima_eventdigest_init()
Replace the '-1' value with HASH_ALGO__LAST in ima_eventdigest_init()
as the called function ima_eventdigest_init_common() expects an unsigned
char.

Fix commit:
  4d7aeee ima: define new template ima-ng and template fields d-ng and n-ng

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-01-03 07:42:59 -05:00
Roberto Sassu
c502c78ba7 ima: change the default hash algorithm to SHA1 in ima_eventdigest_ng_init()
Replace HASH_ALGO__LAST with HASH_ALGO_SHA1 as the initial value of
the hash algorithm so that the prefix 'sha1:' is added to violation
digests.

Fix commit:
  4d7aeee ima: define new template ima-ng and template fields d-ng and n-ng

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Cc: <stable@vger.kernel.org> # 3.13.x
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-01-03 07:42:57 -05:00
Roberto Sassu
a7ed7c60e1 ima: properly free ima_template_entry structures
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>
2013-12-02 20:46:56 -05:00