Different hooks can require different methods for appraising a
file's integrity. As a result, an integrity appraisal status is
cached on a per hook basis.
Only a hook specific rule, requires the inode to be re-appraised.
This patch eliminates unnecessary appraisals.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
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: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
In preparation for hook specific appraise status results, increase
the iint flags size.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
The 'security.ima' extended attribute may contain either the file data's
hash or a digital signature. This patch adds support for requiring a
specific extended attribute type. It extends the IMA policy with a new
keyword 'appraise_type=imasig'. (Default is hash.)
Changelog v2:
- Fixed Documentation/ABI/testing/ima_policy option syntax
Changelog v1:
- Differentiate between 'required' vs. 'actual' extended attribute
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch forbids write access to files with digital signatures, as they
are considered immutable.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Define a new function ima_d_path(), which returns the full pathname.
This function will be used further, for example, by the directory
verification code.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch reduces size of the iint structure by 8 bytes.
It saves about 15% of iint cache memory.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Based on the IMA appraisal policy, files are appraised. For those
files appraised, the IMA hooks return the integrity appraisal result,
assuming IMA-appraisal is in enforcing mode. This patch combines
both of these criteria (in policy and enforcing file integrity),
removing the checking duplication.
Changelog v1:
- Update hook comments
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
When a file system is mounted read-only, setting the xattr value in
fix mode fails with an error code -EROFS. The xattr should be fixed
after the file system is remounted read-write. This patch verifies
that the set xattr succeeds, before setting the appraise status value
to INTEGRITY_PASS.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Although the IMA policy does not change, the LSM policy can be
reloaded, leaving the IMA LSM based rules referring to the old,
stale LSM policy. This patch updates the IMA LSM based rules
to reflect the reloaded LSM policy.
Reported-by: Sven Vermeulen <sven.vermeulen@siphos.be>
tested-by: Sven Vermeulen <sven.vermeulen@siphos.be>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Pull networking fixes from David Miller:
1) Really fix tuntap SKB use after free bug, from Eric Dumazet.
2) Adjust SKB data pointer to point past the transport header before
calling icmpv6_notify() so that the headers are in the state which
that function expects. From Duan Jiong.
3) Fix ambiguities in the new tuntap multi-queue APIs. From Jason
Wang.
4) mISDN needs to use del_timer_sync(), from Konstantin Khlebnikov.
5) Don't destroy mutex after freeing up device private in mac802154,
fix also from Konstantin Khlebnikov.
6) Fix INET request socket leak in TCP and DCCP, from Christoph Paasch.
7) SCTP HMAC kconfig rework, from Neil Horman.
8) Fix SCTP jprobes function signature, otherwise things explode, from
Daniel Borkmann.
9) Fix typo in ipv6-offload Makefile variable reference, from Simon
Arlott.
10) Don't fail USBNET open just because remote wakeup isn't supported,
from Oliver Neukum.
11) be2net driver bug fixes from Sathya Perla.
12) SOLOS PCI ATM driver bug fixes from Nathan Williams and David
Woodhouse.
13) Fix MTU changing regression in 8139cp driver, from John Greene.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (45 commits)
solos-pci: ensure all TX packets are aligned to 4 bytes
solos-pci: add firmware upgrade support for new models
solos-pci: remove superfluous debug output
solos-pci: add GPIO support for newer versions on Geos board
8139cp: Prevent dev_close/cp_interrupt race on MTU change
net: qmi_wwan: add ZTE MF880
drivers/net: Use of_match_ptr() macro in smsc911x.c
drivers/net: Use of_match_ptr() macro in smc91x.c
ipv6: addrconf.c: remove unnecessary "if"
bridge: Correctly encode addresses when dumping mdb entries
bridge: Do not unregister all PF_BRIDGE rtnl operations
use generic usbnet_manage_power()
usbnet: generic manage_power()
usbnet: handle PM failure gracefully
ksz884x: fix receive polling race condition
qlcnic: update driver version
qlcnic: fix unused variable warnings
net: fec: forbid FEC_PTP on SoCs that do not support
be2net: fix wrong frag_idx reported by RX CQ
be2net: fix be_close() to ensure all events are ack'ed
...
Pull module update from Rusty Russell:
"Nothing all that exciting; a new module-from-fd syscall for those who
want to verify the source of the module (ChromeOS) and/or use standard
IMA on it or other security hooks."
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
MODSIGN: Fix kbuild output when using default extra_certificates
MODSIGN: Avoid using .incbin in C source
modules: don't hand 0 to vmalloc.
module: Remove a extra null character at the top of module->strtab.
ASN.1: Use the ASN1_LONG_TAG and ASN1_INDEFINITE_LENGTH constants
ASN.1: Define indefinite length marker constant
moduleparam: use __UNIQUE_ID()
__UNIQUE_ID()
MODSIGN: Add modules_sign make target
powerpc: add finit_module syscall.
ima: support new kernel module syscall
add finit_module syscall to asm-generic
ARM: add finit_module syscall to ARM
security: introduce kernel_module_from_file hook
module: add flags arg to sys_finit_module()
module: add syscall to load module from fd
Pull (again) user namespace infrastructure changes from Eric Biederman:
"Those bugs, those darn embarrasing bugs just want don't want to get
fixed.
Linus I just updated my mirror of your kernel.org tree and it appears
you successfully pulled everything except the last 4 commits that fix
those embarrasing bugs.
When you get a chance can you please repull my branch"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
userns: Fix typo in description of the limitation of userns_install
userns: Add a more complete capability subset test to commit_creds
userns: Require CAP_SYS_ADMIN for most uses of setns.
Fix cap_capable to only allow owners in the parent user namespace to have caps.
Pull user namespace changes from Eric Biederman:
"While small this set of changes is very significant with respect to
containers in general and user namespaces in particular. The user
space interface is now complete.
This set of changes adds support for unprivileged users to create user
namespaces and as a user namespace root to create other namespaces.
The tyranny of supporting suid root preventing unprivileged users from
using cool new kernel features is broken.
This set of changes completes the work on setns, adding support for
the pid, user, mount namespaces.
This set of changes includes a bunch of basic pid namespace
cleanups/simplifications. Of particular significance is the rework of
the pid namespace cleanup so it no longer requires sending out
tendrils into all kinds of unexpected cleanup paths for operation. At
least one case of broken error handling is fixed by this cleanup.
The files under /proc/<pid>/ns/ have been converted from regular files
to magic symlinks which prevents incorrect caching by the VFS,
ensuring the files always refer to the namespace the process is
currently using and ensuring that the ptrace_mayaccess permission
checks are always applied.
The files under /proc/<pid>/ns/ have been given stable inode numbers
so it is now possible to see if different processes share the same
namespaces.
Through the David Miller's net tree are changes to relax many of the
permission checks in the networking stack to allowing the user
namespace root to usefully use the networking stack. Similar changes
for the mount namespace and the pid namespace are coming through my
tree.
Two small changes to add user namespace support were commited here adn
in David Miller's -net tree so that I could complete the work on the
/proc/<pid>/ns/ files in this tree.
Work remains to make it safe to build user namespaces and 9p, afs,
ceph, cifs, coda, gfs2, ncpfs, nfs, nfsd, ocfs2, and xfs so the
Kconfig guard remains in place preventing that user namespaces from
being built when any of those filesystems are enabled.
Future design work remains to allow root users outside of the initial
user namespace to mount more than just /proc and /sys."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (38 commits)
proc: Usable inode numbers for the namespace file descriptors.
proc: Fix the namespace inode permission checks.
proc: Generalize proc inode allocation
userns: Allow unprivilged mounts of proc and sysfs
userns: For /proc/self/{uid,gid}_map derive the lower userns from the struct file
procfs: Print task uids and gids in the userns that opened the proc file
userns: Implement unshare of the user namespace
userns: Implent proc namespace operations
userns: Kill task_user_ns
userns: Make create_new_namespaces take a user_ns parameter
userns: Allow unprivileged use of setns.
userns: Allow unprivileged users to create new namespaces
userns: Allow setting a userns mapping to your current uid.
userns: Allow chown and setgid preservation
userns: Allow unprivileged users to create user namespaces.
userns: Ignore suid and sgid on binaries if the uid or gid can not be mapped
userns: fix return value on mntns_install() failure
vfs: Allow unprivileged manipulation of the mount namespace.
vfs: Only support slave subtrees across different user namespaces
vfs: Add a user namespace reference from struct mnt_namespace
...
Pull security subsystem updates from James Morris:
"A quiet cycle for the security subsystem with just a few maintenance
updates."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
Smack: create a sysfs mount point for smackfs
Smack: use select not depends in Kconfig
Yama: remove locking from delete path
Yama: add RCU to drop read locking
drivers/char/tpm: remove tasklet and cleanup
KEYS: Use keyring_alloc() to create special keyrings
KEYS: Reduce initial permissions on keys
KEYS: Make the session and process keyrings per-thread
seccomp: Make syscall skipping and nr changes more consistent
key: Fix resource leak
keys: Fix unreachable code
KEYS: Add payload preparsing opportunity prior to key instantiate or update
Andy Lutomirski pointed out that the current behavior of allowing the
owner of a user namespace to have all caps when that owner is not in a
parent user namespace is wrong. Add a test to ensure the owner of a user
namespace is in the parent of the user namespace to fix this bug.
Thankfully this bug did not apply to the initial user namespace, keeping
the mischief that can be caused by this bug quite small.
This is bug was introduced in v3.5 by commit 783291e690
"Simplify the user_namespace by making userns->creator a kuid."
But did not matter until the permisions required to create
a user namespace were relaxed allowing a user namespace to be created
inside of a user namespace.
The bug made it possible for the owner of a user namespace to be
present in a child user namespace. Since the owner of a user nameapce
is granted all capabilities it became possible for users in a
grandchild user namespace to have all privilges over their parent user
namspace.
Reorder the checks in cap_capable. This should make the common case
faster and make it clear that nothing magic happens in the initial
user namespace. The reordering is safe because cred->user_ns
can only be in targ_ns or targ_ns->parent but not both.
Add a comment a the top of the loop to make the logic of
the code clear.
Add a distinct variable ns that changes as we walk up
the user namespace hierarchy to make it clear which variable
is changing.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
There are a number of "conventions" for where to put LSM filesystems.
Smack adheres to none of them. Create a mount point at /sys/fs/smackfs
for mounting smackfs so that Smack can be conventional.
Targeted for git://git.gitorious.org/smack-next/kernel.git
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
The components NETLABEL and SECURITY_NETWORK are required by
Smack. Using "depends" in Kconfig hides the Smack option
if the user hasn't figured out that they need to be enabled
while using make menuconfig. Using select is a better choice.
Because select is not recursive depends on NET and SECURITY
are added. The reflects similar usage in TOMOYO and AppArmor.
Targeted for git://git.gitorious.org/smack-next/kernel.git
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
With the addition of the new kernel module syscall, which defines two
arguments - a file descriptor to the kernel module and a pointer to a NULL
terminated string of module arguments - it is now possible to measure and
appraise kernel modules like any other file on the file system.
This patch adds support to measure and appraise kernel modules in an
extensible and consistent manner.
To support filesystems without extended attribute support, additional
patches could pass the signature as the first parameter.
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Now that kernel module origins can be reasoned about, provide a hook to
the LSMs to make policy decisions about the module file. This will let
Chrome OS enforce that loadable kernel modules can only come from its
read-only hash-verified root filesystem. Other LSMs can, for example,
read extended attributes for signatures, etc.
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Acked-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Mimi Zohar
Dmitry Kasatkin
Alan Cox
Linus Torvalds
Amerigo Wang
Eric W. Biederman
Casey Schaufler
Kees Cook