1. 06 2月, 2013 2 次提交
  2. 23 1月, 2013 1 次提交
    • M
      ima: per hook cache integrity appraisal status · d79d72e0
      Mimi Zohar 提交于
      With the new IMA policy 'appraise_type=' option, different hooks
      can require different methods for appraising a file's integrity.
      
      For example, the existing 'ima_appraise_tcb' policy defines a
      generic rule, requiring all root files to be appraised, without
      specfying the appraisal method.  A more specific rule could require
      all kernel modules, for example, to be signed.
      
      appraise fowner=0 func=MODULE_CHECK appraise_type=imasig
      appraise fowner=0
      
      As a result, the integrity appraisal results for the same inode, but
      for different hooks, could differ.  This patch caches the integrity
      appraisal results on a per hook basis.
      
      Changelog v2:
      - Rename ima_cache_status() to ima_set_cache_status()
      - Rename and move get_appraise_status() to ima_get_cache_status()
      Changelog v0:
      - include IMA_APPRAISE/APPRAISED_SUBMASK in IMA_DO/DONE_MASK (Dmitry)
      - Support independent MODULE_CHECK appraise status.
      - fixed IMA_XXXX_APPRAISE/APPRAISED flags
      Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
      Signed-off-by: NDmitry Kasatkin <dmitry.kasatkin@intel.com>
      d79d72e0
  3. 17 1月, 2013 2 次提交
  4. 14 12月, 2012 1 次提交
    • M
      ima: support new kernel module syscall · fdf90729
      Mimi Zohar 提交于
      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: NMimi Zohar <zohar@us.ibm.com>
      Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      fdf90729
  5. 05 10月, 2012 1 次提交
  6. 14 9月, 2012 1 次提交
    • P
      ima: audit log hashes · e7c568e0
      Peter Moody 提交于
      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: NPeter Moody <pmoody@google.com>
      Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
      e7c568e0
  7. 12 9月, 2012 1 次提交
  8. 08 9月, 2012 1 次提交
    • M
      ima: integrity appraisal extension · 2fe5d6de
      Mimi Zohar 提交于
      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: NMimi Zohar <zohar@us.ibm.com>
      Signed-off-by: NDmitry Kasatkin <dmitry.kasatkin@intel.com>
      2fe5d6de
  9. 06 7月, 2012 1 次提交
  10. 10 9月, 2011 1 次提交
  11. 19 7月, 2011 1 次提交
    • M
      integrity: move ima inode integrity data management · f381c272
      Mimi Zohar 提交于
      Move the inode integrity data(iint) management up to the integrity directory
      in order to share the iint among the different integrity models.
      
      Changelog:
      - don't define MAX_DIGEST_SIZE
      - rename several globally visible 'ima_' prefixed functions, structs,
        locks, etc to 'integrity_'
      - replace '20' with SHA1_DIGEST_SIZE
      - reflect location change in appropriate Kconfig and Makefiles
      - remove unnecessary initialization of iint_initialized to 0
      - rebased on current ima_iint.c
      - define integrity_iint_store/lock as static
      
      There should be no other functional changes.
      Signed-off-by: NMimi Zohar <zohar@us.ibm.com>
      Acked-by: NSerge Hallyn <serge.hallyn@ubuntu.com>
      f381c272
  12. 24 2月, 2011 1 次提交
    • M
      ima: remove unnecessary call to ima_must_measure · 1adace9b
      Mimi Zohar 提交于
      The original ima_must_measure() function based its results on cached
      iint information, which required an iint be allocated for all files.
      Currently, an iint is allocated only for files in policy.  As a result,
      for those files in policy, ima_must_measure() is now called twice: once
      to determine if the inode is in the measurement policy and, the second
      time, to determine if it needs to be measured/re-measured.
      
      The second call to ima_must_measure() unnecessarily checks to see if
      the file is in policy. As we already know the file is in policy, this
      patch removes the second unnecessary call to ima_must_measure(), removes
      the vestige iint parameter, and just checks the iint directly to determine
      if the inode has been measured or needs to be measured/re-measured.
      Signed-off-by: NMimi Zohar <zohar@us.ibm.com>
      Acked-by: NEric Paris <eparis@redhat.com>
      1adace9b
  13. 27 10月, 2010 8 次提交
    • E
      IMA: drop refcnt from ima_iint_cache since it isn't needed · 64c62f06
      Eric Paris 提交于
      Since finding a struct ima_iint_cache requires a valid struct inode, and
      the struct ima_iint_cache is supposed to have the same lifetime as a
      struct inode (technically they die together but don't need to be created
      at the same time) we don't have to worry about the ima_iint_cache
      outliving or dieing before the inode.  So the refcnt isn't useful.  Just
      get rid of it and free the structure when the inode is freed.
      Signed-off-by: NEric Paris <eapris@redhat.com>
      Acked-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      64c62f06
    • E
      IMA: move read counter into struct inode · a178d202
      Eric Paris 提交于
      IMA currently allocated an inode integrity structure for every inode in
      core.  This stucture is about 120 bytes long.  Most files however
      (especially on a system which doesn't make use of IMA) will never need
      any of this space.  The problem is that if IMA is enabled we need to
      know information about the number of readers and the number of writers
      for every inode on the box.  At the moment we collect that information
      in the per inode iint structure and waste the rest of the space.  This
      patch moves those counters into the struct inode so we can eventually
      stop allocating an IMA integrity structure except when absolutely
      needed.
      
      This patch does the minimum needed to move the location of the data.
      Further cleanups, especially the location of counter updates, may still
      be possible.
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Acked-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a178d202
    • E
      IMA: use i_writecount rather than a private counter · b9593d30
      Eric Paris 提交于
      IMA tracks the number of struct files which are holding a given inode
      readonly and the number which are holding the inode write or r/w.  It
      needs this information so when a new reader or writer comes in it can
      tell if this new file will be able to invalidate results it already made
      about existing files.
      
      aka if a task is holding a struct file open RO, IMA measured the file
      and recorded those measurements and then a task opens the file RW IMA
      needs to note in the logs that the old measurement may not be correct.
      It's called a "Time of Measure Time of Use" (ToMToU) issue.  The same is
      true is a RO file is opened to an inode which has an open writer.  We
      cannot, with any validity, measure the file in question since it could
      be changing.
      
      This patch attempts to use the i_writecount field to track writers.  The
      i_writecount field actually embeds more information in it's value than
      IMA needs but it should work for our purposes and allow us to shrink the
      struct inode even more.
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Acked-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b9593d30
    • E
      IMA: use inode->i_lock to protect read and write counters · ad16ad00
      Eric Paris 提交于
      Currently IMA used the iint->mutex to protect the i_readcount and
      i_writecount.  This patch uses the inode->i_lock since we are going to
      start using in inode objects and that is the most appropriate lock.
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Acked-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      ad16ad00
    • E
      IMA: convert internal flags from long to char · 15aac676
      Eric Paris 提交于
      The IMA flags is an unsigned long but there is only 1 flag defined.
      Lets save a little space and make it a char.  This packs nicely next to
      the array of u8's.
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Acked-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      15aac676
    • E
      IMA: use unsigned int instead of long for counters · 497f3233
      Eric Paris 提交于
      Currently IMA uses 2 longs in struct inode.  To save space (and as it
      seems impossible to overflow 32 bits) we switch these to unsigned int.
      The switch to unsigned does require slightly different checks for
      underflow, but it isn't complex.
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Acked-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      497f3233
    • E
      IMA: drop the inode opencount since it isn't needed for operation · b575156d
      Eric Paris 提交于
      The opencount was used to help debugging to make sure that everything
      which created a struct file also correctly made the IMA calls.  Since we
      moved all of that into the VFS this isn't as necessary.  We should be
      able to get the same amount of debugging out of just the reader and
      write count.
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Acked-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b575156d
    • E
      IMA: use rbtree instead of radix tree for inode information cache · 85491641
      Eric Paris 提交于
      The IMA code needs to store the number of tasks which have an open fd
      granting permission to write a file even when IMA is not in use.  It
      needs this information in order to be enabled at a later point in time
      without losing it's integrity garantees.
      
      At the moment that means we store a little bit of data about every inode
      in a cache.  We use a radix tree key'd on the inode's memory address.
      Dave Chinner pointed out that a radix tree is a terrible data structure
      for such a sparse key space.  This patch switches to using an rbtree
      which should be more efficient.
      
      Bug report from Dave:
      
       "I just noticed that slabtop was reporting an awfully high usage of
        radix tree nodes:
      
         OBJS ACTIVE  USE OBJ SIZE  SLABS OBJ/SLAB CACHE SIZE NAME
        4200331 2778082  66%    0.55K 144839       29   2317424K radix_tree_node
        2321500 2060290  88%    1.00K  72581       32   2322592K xfs_inode
        2235648 2069791  92%    0.12K  69864       32    279456K iint_cache
      
        That is, 2.7M radix tree nodes are allocated, and the cache itself is
        consuming 2.3GB of RAM.  I know that the XFS inodei caches are indexed
        by radix tree node, but for 2 million cached inodes that would mean a
        density of 1 inode per radix tree node, which for a system with 16M
        inodes in the filsystems is an impossibly low density.  The worst I've
        seen in a production system like kernel.org is about 20-25% density,
        which would mean about 150-200k radix tree nodes for that many inodes.
        So it's not the inode cache.
      
        So I looked up what the iint_cache was.  It appears to used for
        storing per-inode IMA information, and uses a radix tree for indexing.
        It uses the *address* of the struct inode as the indexing key.  That
        means the key space is extremely sparse - for XFS the struct inode
        addresses are approximately 1000 bytes apart, which means the closest
        the radix tree index keys get is ~1000.  Which means that there is a
        single entry per radix tree leaf node, so the radix tree is using
        roughly 550 bytes for every 120byte structure being cached.  For the
        above example, it's probably wasting close to 1GB of RAM...."
      Reported-by: NDave Chinner <david@fromorbit.com>
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Acked-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      85491641
  14. 08 9月, 2010 1 次提交
    • M
      ima: always maintain counters · e950598d
      Mimi Zohar 提交于
      commit 8262bb85da allocated the inode integrity struct (iint) before any
      inodes were created. Only after IMA was initialized in late_initcall were
      the counters updated. This patch updates the counters, whether or not IMA
      has been initialized, to resolve 'imbalance' messages.
      
      This patch fixes the bug as reported in bugzilla: 15673.  When the i915
      is builtin, the ring_buffer is initialized before IMA, causing the
      imbalance message on suspend.
      Reported-by: NThomas Meyer <thomas@m3y3r.de>
      Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
      Tested-by: NThomas Meyer <thomas@m3y3r.de>
      Tested-by: David Safford<safford@watson.ibm.com>
      Cc: Stable Kernel <stable@kernel.org>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      e950598d
  15. 21 4月, 2010 1 次提交
    • E
      ima: handle multiple rules per write · 6ccd0456
      Eric Paris 提交于
      Currently IMA will only accept one rule per write().  This patch allows IMA to
      accept writes which contain multiple rules but only processes one rule per
      write.  \n is used as the delimiter between rules.  IMA will return a short
      write indicating that it only accepted up to the first \n.
      
      This allows simple userspace utilities like cat to be used to load an IMA
      policy instead of needing a special userspace utility that understood 'one
      write per rule'
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Acked-by: NMimi Zohar <zohar@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      6ccd0456
  16. 07 2月, 2010 2 次提交
  17. 17 12月, 2009 3 次提交
  18. 12 2月, 2009 1 次提交
  19. 06 2月, 2009 4 次提交
    • M
      Integrity: IMA file free imbalance · 1df9f0a7
      Mimi Zohar 提交于
      The number of calls to ima_path_check()/ima_file_free()
      should be balanced.  An extra call to fput(), indicates
      the file could have been accessed without first being
      measured.
      
      Although f_count is incremented/decremented in places other
      than fget/fput, like fget_light/fput_light and get_file, the
      current task must already hold a file refcnt.  The call to
      __fput() is delayed until the refcnt becomes 0, resulting
      in ima_file_free() flagging any changes.
      
      - add hook to increment opencount for IPC shared memory(SYSV),
        shmat files, and /dev/zero
      - moved NULL iint test in opencount_get()
      Signed-off-by: NMimi Zohar <zohar@us.ibm.com>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      1df9f0a7
    • M
      integrity: IMA policy · 4af4662f
      Mimi Zohar 提交于
      Support for a user loadable policy through securityfs
      with support for LSM specific policy data.
      - free invalid rule in ima_parse_add_rule()
      Signed-off-by: NMimi Zohar <zohar@us.ibm.com>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      4af4662f
    • M
      integrity: IMA display · bab73937
      Mimi Zohar 提交于
      Make the measurement lists available through securityfs.
      - removed test for NULL return code from securityfs_create_file/dir
      Signed-off-by: NMimi Zohar <zohar@us.ibm.com>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      bab73937
    • M
      integrity: IMA as an integrity service provider · 3323eec9
      Mimi Zohar 提交于
      IMA provides hardware (TPM) based measurement and attestation for
      file measurements. As the Trusted Computing (TPM) model requires,
      IMA measures all files before they are accessed in any way (on the
      integrity_bprm_check, integrity_path_check and integrity_file_mmap
      hooks), and commits the measurements to the TPM. Once added to the
      TPM, measurements can not be removed.
      
      In addition, IMA maintains a list of these file measurements, which
      can be used to validate the aggregate value stored in the TPM.  The
      TPM can sign these measurements, and thus the system can prove, to
      itself and to a third party, the system's integrity in a way that
      cannot be circumvented by malicious or compromised software.
      
      - alloc ima_template_entry before calling ima_store_template()
      - log ima_add_boot_aggregate() failure
      - removed unused IMA_TEMPLATE_NAME_LEN
      - replaced hard coded string length with #define name
      Signed-off-by: NMimi Zohar <zohar@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      3323eec9