The switch to uuid_t invereted the logic of verfication that &entry->fsuuid
is zero during parsing of "fsuuid=" rule. Instead of making sure the
&entry->fsuuid field is not attempted to be overwritten, we bail out for
perfectly correct rule.
Fixes: 787d8c530a ("ima/policy: switch to use uuid_t")
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
i_version is only supported by a filesystem when the SB_I_VERSION
flag is set. This patch tests for the SB_I_VERSION flag before using
i_version. If we can't use i_version to detect a file change then we
must assume the file has changed in the last_writer path and remeasure
it.
On filesystems without i_version support IMA used to measure a file
only once and didn't detect any changes to a file. With this patch
IMA now works properly on these filesystems.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Simple but useful message log to the user in case of module appraise is
forced and fails due to the lack of file descriptor, that might be
caused by kmod calls to compressed modules.
Signed-off-by: Bruno E. O. Meneguele <brdeoliv@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
ima_rdwr_violation_check() retrieves the full path of a measured file by
calling ima_d_path(). If process_measurement() calls this function, it
reuses the pointer and passes it to the functions to measure/appraise/audit
an accessed file.
After commit bc15ed663e ("ima: fix ima_d_path() possible race with
rename"), ima_d_path() first tries to retrieve the full path by calling
d_absolute_path() and, if there is an error, copies the dentry name to the
buffer passed as argument.
However, ima_rdwr_violation_check() passes to ima_d_path() the pointer of a
local variable. process_measurement() might be reusing the pointer to an
area in the stack which may have been already overwritten after
ima_rdwr_violation_check() returned.
Correct this issue by passing to ima_rdwr_violation_check() the pointer of
a buffer declared in process_measurement().
Fixes: bc15ed663e ("ima: fix ima_d_path() possible race with rename")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Line continuations with excess spacing causes unexpected output.
Based on commit 6f76b6fcaa ("CodingStyle: Document the exception of
not splitting user-visible strings, for grepping") recommendation.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The builtin ima_appraise_tcb policy, which is specified on the boot
command line, can be replaced with a custom policy, normally early in
the boot process. Custom policies can be more restrictive in some ways,
like requiring file signatures, but can be less restrictive in other
ways, like not appraising mutable files. With a less restrictive policy
in place, files in the builtin policy might not be hashed and labeled
with a security.ima hash. On reboot, files which should be labeled in
the ima_appraise_tcb are not labeled, possibly preventing the system
from booting properly.
To resolve this problem, this patch extends the existing IMA policy
actions "measure", "dont_measure", "appraise", "dont_appraise", and
"audit" with "hash" and "dont_hash". The new "hash" action will write
the file hash as security.ima, but without requiring the file to be
appraised as well.
For example, the builtin ima_appraise_tcb policy includes the rule,
"appraise fowner=0". Adding the "hash fowner=0" rule to a custom
policy, will cause the needed file hashes to be calculated and written
as security.ima xattrs.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Before IMA appraisal was introduced, IMA was using own integrity cache
lock along with i_mutex. process_measurement and ima_file_free took
the iint->mutex first and then the i_mutex, while setxattr, chmod and
chown took the locks in reverse order. To resolve the potential deadlock,
i_mutex was moved to protect entire IMA functionality and the redundant
iint->mutex was eliminated.
Solution was based on the assumption that filesystem code does not take
i_mutex further. But when file is opened with O_DIRECT flag, direct-io
implementation takes i_mutex and produces deadlock. Furthermore, certain
other filesystem operations, such as llseek, also take i_mutex.
More recently some filesystems have replaced their filesystem specific
lock with the global i_rwsem to read a file. As a result, when IMA
attempts to calculate the file hash, reading the file attempts to take
the i_rwsem again.
To resolve O_DIRECT related deadlock problem, this patch re-introduces
iint->mutex. But to eliminate the original chmod() related deadlock
problem, this patch eliminates the requirement for chmod hooks to take
the iint->mutex by introducing additional atomic iint->attr_flags to
indicate calling of the hooks. The allowed locking order is to take
the iint->mutex first and then the i_rwsem.
Original flags were cleared in chmod(), setxattr() or removwxattr()
hooks and tested when file was closed or opened again. New atomic flags
are set or cleared in those hooks and tested to clear iint->flags on
close or on open.
Atomic flags are following:
* IMA_CHANGE_ATTR - indicates that chATTR() was called (chmod, chown,
chgrp) and file attributes have changed. On file open, it causes IMA
to clear iint->flags to re-evaluate policy and perform IMA functions
again.
* IMA_CHANGE_XATTR - indicates that setxattr or removexattr was called
and extended attributes have changed. On file open, it causes IMA to
clear iint->flags IMA_DONE_MASK to re-appraise.
* IMA_UPDATE_XATTR - indicates that security.ima needs to be updated.
It is cleared if file policy changes and no update is needed.
* IMA_DIGSIG - indicates that file security.ima has signature and file
security.ima must not update to file has on file close.
* IMA_MUST_MEASURE - indicates the file is in the measurement policy.
Fixes: Commit 6552321831 ("xfs: remove i_iolock and use i_rwsem in
the VFS inode instead")
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The EVM signature includes the inode number and (optionally) the
filesystem UUID, making it impractical to ship EVM signatures in
packages. This patch adds a new portable format intended to allow
distributions to include EVM signatures. It is identical to the existing
format but hardcodes the inode and generation numbers to 0 and does not
include the filesystem UUID even if the kernel is configured to do so.
Removing the inode means that the metadata and signature from one file
could be copied to another file without invalidating it. This is avoided
by ensuring that an IMA xattr is present during EVM validation.
Portable signatures are intended to be immutable - ie, they will never
be transformed into HMACs.
Based on earlier work by Dmitry Kasatkin and Mikhail Kurinnoi.
Signed-off-by: Matthew Garrett <mjg59@google.com>
Cc: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Cc: Mikhail Kurinnoi <viewizard@viewizard.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Custom policies can require file signatures based on LSM labels. These
files are normally created and only afterwards labeled, requiring them
to be signed.
Instead of requiring file signatures based on LSM labels, entire
filesystems could require file signatures. In this case, we need the
ability of writing new files without requiring file signatures.
The definition of a "new" file was originally defined as any file with
a length of zero. Subsequent patches redefined a "new" file to be based
on the FILE_CREATE open flag. By combining the open flag with a file
size of zero, this patch relaxes the file signature requirement.
Fixes: 1ac202e978 ima: accept previously set IMA_NEW_FILE
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Commit b65a9cfc2c ("Untangling ima mess, part 2: deal with counters")
moved the call of ima_file_check() from may_open() to do_filp_open() at a
point where the file descriptor is already opened.
This breaks the assumption made by IMA that file descriptors being closed
belong to files whose access was granted by ima_file_check(). The
consequence is that security.ima and security.evm are updated with good
values, regardless of the current appraisal status.
For example, if a file does not have security.ima, IMA will create it after
opening the file for writing, even if access is denied. Access to the file
will be allowed afterwards.
Avoid this issue by checking the appraisal status before updating
security.ima.
Cc: stable@vger.kernel.org
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Pull crypto updates from Herbert Xu:
"Here is the crypto update for 4.15:
API:
- Disambiguate EBUSY when queueing crypto request by adding ENOSPC.
This change touches code outside the crypto API.
- Reset settings when empty string is written to rng_current.
Algorithms:
- Add OSCCA SM3 secure hash.
Drivers:
- Remove old mv_cesa driver (replaced by marvell/cesa).
- Enable rfc3686/ecb/cfb/ofb AES in crypto4xx.
- Add ccm/gcm AES in crypto4xx.
- Add support for BCM7278 in iproc-rng200.
- Add hash support on Exynos in s5p-sss.
- Fix fallback-induced error in vmx.
- Fix output IV in atmel-aes.
- Fix empty GCM hash in mediatek.
Others:
- Fix DoS potential in lib/mpi.
- Fix potential out-of-order issues with padata"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (162 commits)
lib/mpi: call cond_resched() from mpi_powm() loop
crypto: stm32/hash - Fix return issue on update
crypto: dh - Remove pointless checks for NULL 'p' and 'g'
crypto: qat - Clean up error handling in qat_dh_set_secret()
crypto: dh - Don't permit 'key' or 'g' size longer than 'p'
crypto: dh - Don't permit 'p' to be 0
crypto: dh - Fix double free of ctx->p
hwrng: iproc-rng200 - Add support for BCM7278
dt-bindings: rng: Document BCM7278 RNG200 compatible
crypto: chcr - Replace _manual_ swap with swap macro
crypto: marvell - Add a NULL entry at the end of mv_cesa_plat_id_table[]
hwrng: virtio - Virtio RNG devices need to be re-registered after suspend/resume
crypto: atmel - remove empty functions
crypto: ecdh - remove empty exit()
MAINTAINERS: update maintainer for qat
crypto: caam - remove unused param of ctx_map_to_sec4_sg()
crypto: caam - remove unneeded edesc zeroization
crypto: atmel-aes - Reset the controller before each use
crypto: atmel-aes - properly set IV after {en,de}crypt
hwrng: core - Reset user selected rng by writing "" to rng_current
...
Pull security subsystem integrity updates from James Morris:
"There is a mixture of bug fixes, code cleanup, preparatory code for
new functionality and new functionality.
Commit 26ddabfe96 ("evm: enable EVM when X509 certificate is
loaded") enabled EVM without loading a symmetric key, but was limited
to defining the x509 certificate pathname at build. Included in this
set of patches is the ability of enabling EVM, without loading the EVM
symmetric key, from userspace. New is the ability to prevent the
loading of an EVM symmetric key."
* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
ima: Remove redundant conditional operator
ima: Fix bool initialization/comparison
ima: check signature enforcement against cmdline param instead of CONFIG
module: export module signature enforcement status
ima: fix hash algorithm initialization
EVM: Only complain about a missing HMAC key once
EVM: Allow userspace to signal an RSA key has been loaded
EVM: Include security.apparmor in EVM measurements
ima: call ima_file_free() prior to calling fasync
integrity: use kernel_read_file_from_path() to read x509 certs
ima: always measure and audit files in policy
ima: don't remove the securityfs policy file
vfs: fix mounting a filesystem with i_version
A non-zero value is converted to 1 when assigned to a bool variable, so the
conditional operator in is_ima_appraise_enabled is redundant.
The value of a comparison operator is either 1 or 0 so the conditional
operator in ima_inode_setxattr is redundant as well.
Confirmed that the patch is correct by comparing the object file from
before and after the patch. They are identical.
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Bool initializations should use true and false. Bool tests don't need
comparisons.
Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
When the user requests MODULE_CHECK policy and its kernel is compiled
with CONFIG_MODULE_SIG_FORCE not set, all modules would not load, just
those loaded in initram time. One option the user would have would be
set a kernel cmdline param (module.sig_enforce) to true, but the IMA
module check code doesn't rely on this value, it checks just
CONFIG_MODULE_SIG_FORCE.
This patch solves this problem checking for the exported value of
module.sig_enforce cmdline param intead of CONFIG_MODULE_SIG_FORCE,
which holds the effective value (CONFIG || param).
Signed-off-by: Bruno E. O. Meneguele <brdeoliv@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The hash_setup function always sets the hash_setup_done flag, even
when the hash algorithm is invalid. This prevents the default hash
algorithm defined as CONFIG_IMA_DEFAULT_HASH from being used.
This patch sets hash_setup_done flag only for valid hash algorithms.
Fixes: e7a2ad7eb6 "ima: enable support for larger default filedata hash
algorithms"
Signed-off-by: Boshi Wang <wangboshi@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The CONFIG_IMA_LOAD_X509 and CONFIG_EVM_LOAD_X509 options permit
loading x509 signed certificates onto the trusted keyrings without
verifying the x509 certificate file's signature.
This patch replaces the call to the integrity_read_file() specific
function with the common kernel_read_file_from_path() function.
To avoid verifying the file signature, this patch defines
READING_X509_CERTFICATE.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
All files matching a "measure" rule must be included in the IMA
measurement list, even when the file hash cannot be calculated.
Similarly, all files matching an "audit" rule must be audited, even when
the file hash can not be calculated.
The file data hash field contained in the IMA measurement list template
data will contain 0's instead of the actual file hash digest.
Note:
In general, adding, deleting or in anyway changing which files are
included in the IMA measurement list is not a good idea, as it might
result in not being able to unseal trusted keys sealed to a specific
TPM PCR value. This patch not only adds file measurements that were
not previously measured, but specifies that the file hash value for
these files will be 0's.
As the IMA measurement list ordering is not consistent from one boot
to the next, it is unlikely that anyone is sealing keys based on the
IMA measurement list. Remote attestation servers should be able to
process these new measurement records, but might complain about
these unknown records.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Reviewed-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
The securityfs policy file is removed unless additional rules can be
appended to the IMA policy (CONFIG_IMA_WRITE_POLICY), regardless as
to whether the policy is configured so that it can be displayed.
This patch changes this behavior, removing the securityfs policy file,
only if CONFIG_IMA_READ_POLICY is also not enabled.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
ima starts several async crypto ops and waits for their completions.
Move it over to generic code doing the same.
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull security layer updates from James Morris:
- a major update for AppArmor. From JJ:
* several bug fixes and cleanups
* the patch to add symlink support to securityfs that was floated
on the list earlier and the apparmorfs changes that make use of
securityfs symlinks
* it introduces the domain labeling base code that Ubuntu has been
carrying for several years, with several cleanups applied. And it
converts the current mediation over to using the domain labeling
base, which brings domain stacking support with it. This finally
will bring the base upstream code in line with Ubuntu and provide
a base to upstream the new feature work that Ubuntu carries.
* This does _not_ contain any of the newer apparmor mediation
features/controls (mount, signals, network, keys, ...) that
Ubuntu is currently carrying, all of which will be RFC'd on top
of this.
- Notable also is the Infiniband work in SELinux, and the new file:map
permission. From Paul:
"While we're down to 21 patches for v4.13 (it was 31 for v4.12),
the diffstat jumps up tremendously with over 2k of line changes.
Almost all of these changes are the SELinux/IB work done by
Daniel Jurgens; some other noteworthy changes include a NFS v4.2
labeling fix, a new file:map permission, and reporting of policy
capabilities on policy load"
There's also now genfscon labeling support for tracefs, which was
lost in v4.1 with the separation from debugfs.
- Smack incorporates a safer socket check in file_receive, and adds a
cap_capable call in privilege check.
- TPM as usual has a bunch of fixes and enhancements.
- Multiple calls to security_add_hooks() can now be made for the same
LSM, to allow LSMs to have hook declarations across multiple files.
- IMA now supports different "ima_appraise=" modes (eg. log, fix) from
the boot command line.
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (126 commits)
apparmor: put back designators in struct initialisers
seccomp: Switch from atomic_t to recount_t
seccomp: Adjust selftests to avoid double-join
seccomp: Clean up core dump logic
IMA: update IMA policy documentation to include pcr= option
ima: Log the same audit cause whenever a file has no signature
ima: Simplify policy_func_show.
integrity: Small code improvements
ima: fix get_binary_runtime_size()
ima: use ima_parse_buf() to parse template data
ima: use ima_parse_buf() to parse measurements headers
ima: introduce ima_parse_buf()
ima: Add cgroups2 to the defaults list
ima: use memdup_user_nul
ima: fix up #endif comments
IMA: Correct Kconfig dependencies for hash selection
ima: define is_ima_appraise_enabled()
ima: define Kconfig IMA_APPRAISE_BOOTPARAM option
ima: define a set of appraisal rules requiring file signatures
ima: extend the "ima_policy" boot command line to support multiple policies
...
If the file doesn't have an xattr, ima_appraise_measurement sets cause to
"missing-hash" while if there's an xattr but it's a digest instead of a
signature it sets cause to "IMA-signature-required".
Fix it by setting cause to "IMA-signature-required" in both cases.
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
If the func_tokens array uses the same indices as enum ima_hooks,
policy_func_show can be a lot simpler, and the func_* enum becomes
unnecessary.
Also, if we use the same macro trick used by kernel_read_file_id_str we can
use one hooks list for both the enum and the string array, making sure they
are always in sync (suggested by Mimi Zohar).
Finally, by using the printf pattern for the function token directly
instead of using the pt macro we can simplify policy_func_show even further
and avoid needing a temporary buffer.
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
These changes are too small to warrant their own patches:
The keyid and sig_size members of struct signature_v2_hdr are in BE format,
so use a type that makes this assumption explicit. Also, use beXX_to_cpu
instead of __beXX_to_cpu to read them.
Change integrity_kernel_read to take a void * buffer instead of char *
buffer, so that callers don't have to use a cast if they provide a buffer
that isn't a char *.
Add missing #endif comment in ima.h pointing out which macro it refers to.
Add missing fall through comment in ima_appraise.c.
Constify mask_tokens and func_tokens arrays.
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Remove '+ 1' from 'size += strlen(entry->template_desc->name) + 1;',
as the template name is sent to userspace without the '\0' character.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The binary_field_data structure definition has been removed from
ima_restore_template_data(). The lengths and data pointers are directly
stored into the template_data array of the ima_template_entry structure.
For template data, both the number of fields and buffer end checks can
be done, as these information are known (respectively from the template
descriptor, and from the measurement header field).
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The binary_hdr_v1 and binary_data_v1 structures defined in
ima_restore_measurement_list() have been replaced with an array of four
ima_field_data structures where pcr, digest, template name and
template data lengths and pointers are stored.
The length of pcr and digest in the ima_field_data array and the bits
in the bitmap are set before ima_parse_buf() is called. The ENFORCE_FIELDS
bit is set for all entries except the last one (there is still data to
parse), and ENFORCE_BUFEND is set only for the last entry.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
ima_parse_buf() takes as input the buffer start and end pointers, and
stores the result in a static array of ima_field_data structures,
where the len field contains the length parsed from the buffer, and
the data field contains the address of the buffer just after the length.
Optionally, the function returns the current value of the buffer pointer
and the number of array elements written.
A bitmap has been added as parameter of ima_parse_buf() to handle
the cases where the length is not prepended to data. Each bit corresponds
to an element of the ima_field_data array. If a bit is set, the length
is not parsed from the buffer, but is read from the corresponding element
of the array (the length must be set before calling the function).
ima_parse_buf() can perform three checks upon request by callers,
depending on the enforce mask passed to it:
- ENFORCE_FIELDS: matching of number of fields (length-data combination)
- there must be enough data in the buffer to parse the number of fields
requested (output: current value of buffer pointer)
- ENFORCE_BUFEND: matching of buffer end
- the ima_field_data array must be large enough to contain lengths and
data pointers for the amount of data requested (output: number
of fields written)
- ENFORCE_FIELDS | ENFORCE_BUFEND: matching of both
Use cases
- measurement entry header: ENFORCE_FIELDS | ENFORCE_BUFEND
- four fields must be parsed: pcr, digest, template name, template data
- ENFORCE_BUFEND is enforced only for the last measurement entry
- template digest (Crypto Agile): ENFORCE_BUFEND
- since only the total template digest length is known, the function
parses length-data combinations until the buffer end is reached
- template data: ENFORCE_FIELDS | ENFORCE_BUFEND
- since the number of fields and the total template data length
are known, the function can perform both checks
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
cgroups2 is beginning to show up in wider usage. Add it to the default
nomeasure/noappraise list like other filesystems.
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Use memdup_user_nul() helper instead of open-coding to simplify the
code.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
While reading the code, I noticed that these #endif comments don't match
how they're actually nested. This patch fixes that.
Signed-off-by: Tycho Andersen <tycho@docker.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
IMA uses the hash algorithm too early to be able to use a module.
Require the selected hash algorithm to be built-in.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Only return enabled if in enforcing mode, not fix or log modes.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Changes:
- Define is_ima_appraise_enabled() as a bool (Thiago Bauermann)
The builtin "ima_appraise_tcb" policy should require file signatures for
at least a few of the hooks (eg. kernel modules, firmware, and the kexec
kernel image), but changing it would break the existing userspace/kernel
ABI.
This patch defines a new builtin policy named "secure_boot", which
can be specified on the "ima_policy=" boot command line, independently
or in conjunction with the "ima_appraise_tcb" policy, by specifing
ima_policy="appraise_tcb | secure_boot". The new appraisal rules
requiring file signatures will be added prior to the "ima_appraise_tcb"
rules.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Changelog:
- Reference secure boot in the new builtin policy name. (Thiago Bauermann)
Add support for providing multiple builtin policies on the "ima_policy="
boot command line. Use "|" as the delimitor separating the policy names.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
For some file systems we still memcpy into it, but in various places this
already allows us to use the proper uuid helpers. More to come..
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com> (Changes to IMA/EVM)
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
This helper was only used by IMA of all things, which would get spurious
errors if CONFIG_BLOCK is disabled. Just opencode the call there.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Replace struct key's restrict_link function pointer with a pointer to
the new struct key_restriction. The structure contains pointers to the
restriction function as well as relevant data for evaluating the
restriction.
The garbage collector checks restrict_link->keytype when key types are
unregistered. Restrictions involving a removed key type are converted
to use restrict_link_reject so that restrictions cannot be removed by
unregistering key types.
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
For now we have only "=" operator for fowner/uid/euid rules. This
patch provide two more operators - ">" and "<" in order to make
fowner/uid/euid rules more flexible.
Examples of usage.
Appraise all files owned by special and system users (SYS_UID_MAX 999):
appraise fowner<1000
Don't appraise files owned by normal users (UID_MIN 1000):
dont_appraise fowner>999
Appraise all files owned by users with UID 1000-1010:
dont_appraise fowner>1010
appraise fowner>999
Changelog v3:
- Removed code duplication in ima_parse_rule().
- Fix ima_policy_show() - (Mimi)
Changelog v2:
- Fixed default policy rules.
Signed-off-by: Mikhail Kurinnoi <viewizard@viewizard.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
security/integrity/ima/ima_policy.c | 115 +++++++++++++++++++++++++++---------
1 file changed, 87 insertions(+), 28 deletions(-)
Modifying the attributes of a file makes ima_inode_post_setattr reset
the IMA cache flags. So if the file, which has just been created,
is opened a second time before the first file descriptor is closed,
verification fails since the security.ima xattr has not been written
yet. We therefore have to look at the IMA_NEW_FILE even if the file
already existed.
With this patch there should no longer be an error when cat tries to
open testfile:
$ rm -f testfile
$ ( echo test >&3 ; touch testfile ; cat testfile ) 3>testfile
A file being new is no reason to accept that it is missing a digital
signature demanded by the policy.
Signed-off-by: Daniel Glöckner <dg@emlix.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The default IMA rules are loaded during init and then do not
change, so mark them as __ro_after_init.
Signed-off-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Otherwise some mask and inmask tokens with MAY_APPEND flag may not work
as expected.
Signed-off-by: Lans Zhang <jia.zhang@windriver.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
On failure to return a pathname from ima_d_path(), a pointer to
dname is returned, which is subsequently used in the IMA measurement
list, the IMA audit records, and other audit logging. Saving the
pointer to dname for later use has the potential to race with rename.
Intead of returning a pointer to dname on failure, this patch returns
a pointer to a copy of the filename.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
For remote attestion it is important for the ima measurement values to
be platform-independent. Therefore integer fields to be hashed must be
converted to canonical format.
Link: http://lkml.kernel.org/r/1480554346-29071-11-git-send-email-zohar@linux.vnet.ibm.com
Signed-off-by: Andreas Steffen <andreas.steffen@strongswan.org>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: Josh Sklar <sklar@linux.vnet.ibm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The IMA binary_runtime_measurements list is currently in platform native
format.
To allow restoring a measurement list carried across kexec with a
different endianness than the targeted kernel, this patch defines
little-endian as the canonical format. For big endian systems wanting
to save/restore the measurement list from a system with a different
endianness, a new boot command line parameter named "ima_canonical_fmt"
is defined.
Considerations: use of the "ima_canonical_fmt" boot command line option
will break existing userspace applications on big endian systems
expecting the binary_runtime_measurements list to be in platform native
format.
Link: http://lkml.kernel.org/r/1480554346-29071-10-git-send-email-zohar@linux.vnet.ibm.com
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andreas Steffen <andreas.steffen@strongswan.org>
Cc: Josh Sklar <sklar@linux.vnet.ibm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The configured IMA measurement list template format can be replaced at
runtime on the boot command line, including a custom template format.
This patch adds support for restoring a measuremement list containing
multiple builtin/custom template formats.
Link: http://lkml.kernel.org/r/1480554346-29071-9-git-send-email-zohar@linux.vnet.ibm.com
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andreas Steffen <andreas.steffen@strongswan.org>
Cc: Josh Sklar <sklar@linux.vnet.ibm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
