Commit Graph

370 Commits

Author SHA1 Message Date
Linus Torvalds
bb7aeae3d6 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security layer updates from James Morris:
 "There are a bunch of fixes to the TPM, IMA, and Keys code, with minor
  fixes scattered across the subsystem.

  IMA now requires signed policy, and that policy is also now measured
  and appraised"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (67 commits)
  X.509: Make algo identifiers text instead of enum
  akcipher: Move the RSA DER encoding check to the crypto layer
  crypto: Add hash param to pkcs1pad
  sign-file: fix build with CMS support disabled
  MAINTAINERS: update tpmdd urls
  MODSIGN: linux/string.h should be #included to get memcpy()
  certs: Fix misaligned data in extra certificate list
  X.509: Handle midnight alternative notation in GeneralizedTime
  X.509: Support leap seconds
  Handle ISO 8601 leap seconds and encodings of midnight in mktime64()
  X.509: Fix leap year handling again
  PKCS#7: fix unitialized boolean 'want'
  firmware: change kernel read fail to dev_dbg()
  KEYS: Use the symbol value for list size, updated by scripts/insert-sys-cert
  KEYS: Reserve an extra certificate symbol for inserting without recompiling
  modsign: hide openssl output in silent builds
  tpm_tis: fix build warning with tpm_tis_resume
  ima: require signed IMA policy
  ima: measure and appraise the IMA policy itself
  ima: load policy using path
  ...
2016-03-17 11:33:45 -07:00
James Morris
88a1b564a2 Merge tag 'keys-next-20160303' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs into next 2016-03-04 11:39:53 +11:00
David Howells
4e8ae72a75 X.509: Make algo identifiers text instead of enum
Make the identifier public key and digest algorithm fields text instead of
enum.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-03-03 21:49:27 +00:00
David Howells
d43de6c780 akcipher: Move the RSA DER encoding check to the crypto layer
Move the RSA EMSA-PKCS1-v1_5 encoding from the asymmetric-key public_key
subtype to the rsa crypto module's pkcs1pad template.  This means that the
public_key subtype no longer has any dependencies on public key type.

To make this work, the following changes have been made:

 (1) The rsa pkcs1pad template is now used for RSA keys.  This strips off the
     padding and returns just the message hash.

 (2) In a previous patch, the pkcs1pad template gained an optional second
     parameter that, if given, specifies the hash used.  We now give this,
     and pkcs1pad checks the encoded message E(M) for the EMSA-PKCS1-v1_5
     encoding and verifies that the correct digest OID is present.

 (3) The crypto driver in crypto/asymmetric_keys/rsa.c is now reduced to
     something that doesn't care about what the encryption actually does
     and and has been merged into public_key.c.

 (4) CONFIG_PUBLIC_KEY_ALGO_RSA is gone.  Module signing must set
     CONFIG_CRYPTO_RSA=y instead.

Thoughts:

 (*) Should the encoding style (eg. raw, EMSA-PKCS1-v1_5) also be passed to
     the padding template?  Should there be multiple padding templates
     registered that share most of the code?

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-03-03 21:49:27 +00:00
Mimi Zohar
95ee08fa37 ima: require signed IMA policy
Require the IMA policy to be signed when additional rules can be added.

v1:
- initialize the policy flag
- include IMA_APPRAISE_POLICY in the policy flag

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>
2016-02-21 09:34:23 -05:00
Mimi Zohar
19f8a84713 ima: measure and appraise the IMA policy itself
Add support for measuring and appraising the IMA policy itself.

Changelog v4:
- use braces on both if/else branches, even if single line on one of the
branches - Dmitry
- Use the id mapping - Dmitry

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>
2016-02-21 09:34:22 -05:00
Dmitry Kasatkin
7429b09281 ima: load policy using path
We currently cannot do appraisal or signature vetting of IMA policies
since we currently can only load IMA policies by writing the contents
of the policy directly in, as follows:

cat policy-file > <securityfs>/ima/policy

If we provide the kernel the path to the IMA policy so it can load
the policy itself it'd be able to later appraise or vet the file
signature if it has one.  This patch adds support to load the IMA
policy with a given path as follows:

echo /etc/ima/ima_policy > /sys/kernel/security/ima/policy

Changelog v4+:
- moved kernel_read_file_from_path() error messages to callers
v3:
- moved kernel_read_file_from_path() to a separate patch
v2:
- after re-ordering the patches, replace calling integrity_kernel_read()
  to read the file with kernel_read_file_from_path() (Mimi)
- Patch description re-written by Luis R. Rodriguez

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2016-02-21 09:34:05 -05:00
Mimi Zohar
d9ddf077bb ima: support for kexec image and initramfs
Add IMA policy support for measuring/appraising the kexec image and
initramfs. Two new IMA policy identifiers KEXEC_KERNEL_CHECK and
KEXEC_INITRAMFS_CHECK are defined.

Example policy rules:
measure func=KEXEC_KERNEL_CHECK
appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig
measure func=KEXEC_INITRAMFS_CHECK
appraise func=KEXEC_INITRAMFS_CHECK appraise_type=imasig

Moving the enumeration to the vfs layer simplified the patches, allowing
the IMA changes, for the most part, to be separated from the other
changes.  Unfortunately, passing either a kernel_read_file_id or a
ima_hooks enumeration within IMA is messy.

Option 1: duplicate kernel_read_file enumeration in ima_hooks

enum kernel_read_file_id {
	...
        READING_KEXEC_IMAGE,
        READING_KEXEC_INITRAMFS,
        READING_MAX_ID

enum ima_hooks {
	...
	KEXEC_KERNEL_CHECK
	KEXEC_INITRAMFS_CHECK

Option 2: define ima_hooks as extension of kernel_read_file
eg: enum ima_hooks {
        FILE_CHECK = READING_MAX_ID,
        MMAP_CHECK,

In order to pass both kernel_read_file_id and ima_hooks values, we
would need to specify a struct containing a union.

struct caller_id {
        union {
                enum ima_hooks func_id;
                enum kernel_read_file_id read_id;
        };
};

Option 3: incorportate the ima_hooks enumeration into kernel_read_file_id,
perhaps changing the enumeration name.

For now, duplicate the new READING_KEXEC_IMAGE/INITRAMFS in the ima_hooks.

Changelog v4:
- replaced switch statement with a kernel_read_file_id to an ima_hooks
id mapping array - Dmitry
- renamed ima_hook tokens KEXEC_CHECK and INITRAMFS_CHECK to
KEXEC_KERNEL_CHECK and KEXEC_INITRAMFS_CHECK respectively - Dave Young

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>
Cc: Dave Young <dyoung@redhat.com>
2016-02-21 09:06:16 -05:00
Mimi Zohar
c6af8efe97 ima: remove firmware and module specific cached status info
Each time a file is read by the kernel, the file should be re-measured and
the file signature re-appraised, based on policy.  As there is no need to
preserve the status information, this patch replaces the firmware and
module specific cache status with a generic one named read_file.

This change simplifies adding support for other files read by the kernel.

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>
2016-02-21 09:06:13 -05:00
Mimi Zohar
a1db742094 module: replace copy_module_from_fd with kernel version
Replace copy_module_from_fd() with kernel_read_file_from_fd().

Although none of the upstreamed LSMs define a kernel_module_from_file
hook, IMA is called, based on policy, to prevent unsigned kernel modules
from being loaded by the original kernel module syscall and to
measure/appraise signed kernel modules.

The security function security_kernel_module_from_file() was called prior
to reading a kernel module.  Preventing unsigned kernel modules from being
loaded by the original kernel module syscall remains on the pre-read
kernel_read_file() security hook.  Instead of reading the kernel module
twice, once for measuring/appraising and again for loading the kernel
module, the signature validation is moved to the kernel_post_read_file()
security hook.

This patch removes the security_kernel_module_from_file() hook and security
call.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
2016-02-21 09:06:12 -05:00
Mimi Zohar
39eeb4fb97 security: define kernel_read_file hook
The kernel_read_file security hook is called prior to reading the file
into memory.

Changelog v4+:
- export security_kernel_read_file()

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Luis R. Rodriguez <mcgrof@kernel.org>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2016-02-21 09:06:09 -05:00
Mimi Zohar
e40ba6d56b firmware: replace call to fw_read_file_contents() with kernel version
Replace the fw_read_file_contents with kernel_file_read_from_path().

Although none of the upstreamed LSMs define a kernel_fw_from_file hook,
IMA is called by the security function to prevent unsigned firmware from
being loaded and to measure/appraise signed firmware, based on policy.

Instead of reading the firmware twice, once for measuring/appraising the
firmware and again for reading the firmware contents into memory, the
kernel_post_read_file() security hook calculates the file hash based on
the in memory file buffer.  The firmware is read once.

This patch removes the LSM kernel_fw_from_file() hook and security call.

Changelog v4+:
- revert dropped buf->size assignment - reported by Sergey Senozhatsky
v3:
- remove kernel_fw_from_file hook
- use kernel_file_read_from_path() - requested by Luis
v2:
- reordered and squashed firmware patches
- fix MAX firmware size (Kees Cook)

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Luis R. Rodriguez <mcgrof@kernel.org>
2016-02-21 09:03:44 -05:00
Mimi Zohar
cf22221786 ima: define a new hook to measure and appraise a file already in memory
This patch defines a new IMA hook ima_post_read_file() for measuring
and appraising files read by the kernel. The caller loads the file into
memory before calling this function, which calculates the hash followed by
the normal IMA policy based processing.

Changelog v5:
- fail ima_post_read_file() if either file or buf is NULL
v3:
- rename ima_hash_and_process_file() to ima_post_read_file()

v1:
- split patch

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
2016-02-20 22:35:08 -05:00
Mimi Zohar
98304bcf71 ima: calculate the hash of a buffer using aynchronous hash(ahash)
Setting up ahash has some overhead.  Only use ahash to calculate the
hash of a buffer, if the buffer is larger than ima_ahash_minsize.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
2016-02-18 17:14:44 -05:00
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
Tadeusz Struk
eb5798f2e2 integrity: convert digsig to akcipher api
Convert asymmetric_verify to akcipher api.

Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David Howells <dhowells@redhat.com>
2016-02-18 14:52:32 +00:00
Ryan Ware
613317bd21 EVM: Use crypto_memneq() for digest comparisons
This patch fixes vulnerability CVE-2016-2085.  The problem exists
because the vm_verify_hmac() function includes a use of memcmp().
Unfortunately, this allows timing side channel attacks; specifically
a MAC forgery complexity drop from 2^128 to 2^12.  This patch changes
the memcmp() to the cryptographically safe crypto_memneq().

Reported-by: Xiaofei Rex Guo <xiaofei.rex.guo@intel.com>
Signed-off-by: Ryan Ware <ware@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2016-02-12 18:36:47 +11:00
David Howells
50d35015ff KEYS: CONFIG_KEYS_DEBUG_PROC_KEYS is no longer an option
CONFIG_KEYS_DEBUG_PROC_KEYS is no longer an option as /proc/keys is now
mandatory if the keyrings facility is enabled (it's used by libkeyutils in
userspace).

The defconfig references were removed with:

	perl -p -i -e 's/CONFIG_KEYS_DEBUG_PROC_KEYS=y\n//' \
	    `git grep -l CONFIG_KEYS_DEBUG_PROC_KEYS=y`

and the integrity Kconfig fixed by hand.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Andreas Ziegler <andreas.ziegler@fau.de>
cc: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
2016-02-10 10:13:27 +00:00
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
Linus Torvalds
5807fcaa9b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:

 - EVM gains support for loading an x509 cert from the kernel
   (EVM_LOAD_X509), into the EVM trusted kernel keyring.

 - Smack implements 'file receive' process-based permission checking for
   sockets, rather than just depending on inode checks.

 - Misc enhancments for TPM & TPM2.

 - Cleanups and bugfixes for SELinux, Keys, and IMA.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (41 commits)
  selinux: Inode label revalidation performance fix
  KEYS: refcount bug fix
  ima: ima_write_policy() limit locking
  IMA: policy can be updated zero times
  selinux: rate-limit netlink message warnings in selinux_nlmsg_perm()
  selinux: export validatetrans decisions
  gfs2: Invalid security labels of inodes when they go invalid
  selinux: Revalidate invalid inode security labels
  security: Add hook to invalidate inode security labels
  selinux: Add accessor functions for inode->i_security
  security: Make inode argument of inode_getsecid non-const
  security: Make inode argument of inode_getsecurity non-const
  selinux: Remove unused variable in selinux_inode_init_security
  keys, trusted: seal with a TPM2 authorization policy
  keys, trusted: select hash algorithm for TPM2 chips
  keys, trusted: fix: *do not* allow duplicate key options
  tpm_ibmvtpm: properly handle interrupted packet receptions
  tpm_tis: Tighten IRQ auto-probing
  tpm_tis: Refactor the interrupt setup
  tpm_tis: Get rid of the duplicate IRQ probing code
  ...
2016-01-17 19:13:15 -08:00
Al Viro
cc4e719e83 fix the leak in integrity_read_file()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-04 10:28:19 -05:00