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* ima: allow to check MAY_APPENDLans Zhang2017-01-271-3/+3
| | | | | | | | 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>
* ima: fix ima_d_path() possible race with renameMimi Zohar2017-01-271-3/+5
| | | | | | | | | | | | | | 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
* ima: store the builtin/custom template definitions in a listMimi Zohar2016-12-201-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | The builtin and single custom templates are currently stored in an array. In preparation for being able to restore a measurement list containing multiple builtin/custom templates, this patch stores the builtin and custom templates as a linked list. This will permit defining more than one custom template per boot. Link: http://lkml.kernel.org/r/1480554346-29071-8-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>
* ima: use file_dentry()Miklos Szeredi2016-09-161-1/+1
| | | | | | | | | | | Ima tries to call ->setxattr() on overlayfs dentry after having locked underlying inode, which results in a deadlock. Reported-by: Krisztian Litkey <kli@iki.fi> Fixes: 4bacc9c9234c ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Cc: <stable@vger.kernel.org> # v4.2 Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: change integrity cache to store measured pcrEric Richter2016-06-301-1/+6
| | | | | | | | | | | | | | IMA avoids re-measuring files by storing the current state as a flag in the integrity cache. It will then skip adding a new measurement log entry if the cache reports the file as already measured. If a policy measures an already measured file to a new PCR, the measurement will not be added to the list. This patch implements a new bitfield for specifying which PCR the file was measured into, rather than if it was measured. Signed-off-by: Eric Richter <erichte@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: include pcr for each measurement log entryEric Richter2016-06-301-1/+1
| | | | | | | | | The IMA measurement list entries include the Kconfig defined PCR value. This patch defines a new ima_template_entry field for including the PCR as specified in the policy rule. Signed-off-by: Eric Richter <erichte@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: extend ima_get_action() to return the policy pcrEric Richter2016-06-301-1/+2
| | | | | | | | | | Different policy rules may extend different PCRs. This patch retrieves the specific PCR for the matched rule. Subsequent patches will include the rule specific PCR in the measurement list and extend the appropriate PCR. Signed-off-by: Eric Richter <erichte@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: add support for creating files using the mknodat syscallMimi Zohar2016-05-011-1/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 3034a14 "ima: pass 'opened' flag to identify newly created files" stopped identifying empty files as new files. However new empty files can be created using the mknodat syscall. On systems with IMA-appraisal enabled, these empty files are not labeled with security.ima extended attributes properly, preventing them from subsequently being opened in order to write the file data contents. This patch defines a new hook named ima_post_path_mknod() to mark these empty files, created using mknodat, as new in order to allow the file data contents to be written. In addition, files with security.ima xattrs containing a file signature are considered "immutable" and can not be modified. The file contents need to be written, before signing the file. This patch relaxes this requirement for new files, allowing the file signature to be written before the file contents. Changelog: - defer identifying files with signatures stored as security.ima (based on Dmitry Rozhkov's comments) - removing tests (eg. dentry, dentry->d_inode, inode->i_size == 0) (based on Al's review) Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Al Viro <<viro@zeniv.linux.org.uk> Tested-by: Dmitry Rozhkov <dmitry.rozhkov@linux.intel.com>
* ima: measure and appraise the IMA policy itselfMimi Zohar2016-02-211-0/+1
| | | | | | | | | | | | | 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>
* ima: support for kexec image and initramfsMimi Zohar2016-02-211-6/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* module: replace copy_module_from_fd with kernel versionMimi Zohar2016-02-211-22/+13
| | | | | | | | | | | | | | | | | | | | | | | | | 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>
* security: define kernel_read_file hookMimi Zohar2016-02-211-0/+16
| | | | | | | | | | | | | 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>
* firmware: replace call to fw_read_file_contents() with kernel versionMimi Zohar2016-02-211-11/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* ima: define a new hook to measure and appraise a file already in memoryMimi Zohar2016-02-201-8/+37
| | | | | | | | | | | | | | | | | | 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>
* ima: use "ima_hooks" enum as function argumentMimi Zohar2016-02-181-7/+7
| | | | | | | | 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>
* ima: separate 'security.ima' reading functionality from collectDmitry Kasatkin2016-02-181-4/+7
| | | | | | | | | | 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>
* wrappers for ->i_mutex accessAl Viro2016-01-221-4/+4
| | | | | | | | | | | 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>
* ima: pass iint to ima_add_violation()Roberto Sassu2015-05-211-2/+3
| | | | | | | | | | | | | | | | | | This patch adds the iint associated to the current inode as a new parameter of ima_add_violation(). The passed iint is always not NULL if a violation is detected. This modification will be used to determine the inode for which there is a violation. Since the 'd' and 'd-ng' template field init() functions were detecting a violation from the value of the iint pointer, they now check the new field 'violation', added to the 'ima_event_data' structure. Changelog: - v1: - modified an old comment (Roberto Sassu) Signed-off-by: Roberto Sassu <rsassu@suse.de> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: use path names cacheDmitry Kasatkin2014-10-071-1/+2
| | | | | | | | __getname() uses slab allocation which is faster than kmalloc. Make use of it. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: check ima_policy_flag in the ima_file_free() hookDmitry Kasatkin2014-10-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | This patch completes the switching to the 'ima_policy_flag' variable in the checks at the beginning of IMA functions, starting with the commit a756024e. Checking 'iint_initialized' is completely unnecessary, because S_IMA flag is unset if iint was not allocated. At the same time the integrity cache is allocated with SLAB_PANIC and the kernel will panic if the allocation fails during kernel initialization. So on a running system iint_initialized is always true and can be removed. Changes in v3: * not limiting test to IMA_APPRAISE (spotted by Roberto Sassu) Changes in v2: * 'iint_initialized' removal patch merged to this patch (requested by Mimi) Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Acked-by: Roberto Sassu <roberto.sassu@polito.it>
* ima: detect violations for mmaped filesRoberto Sassu2014-09-181-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes the detection of the 'open_writers' violation for mmaped files. before) an 'open_writers' violation is detected if the policy contains a rule with the criteria: func=FILE_CHECK mask=MAY_READ after) an 'open_writers' violation is detected if the current event matches one of the policy rules. With the old behaviour, the 'open_writers' violation is not detected in the following case: policy: measure func=FILE_MMAP mask=MAY_EXEC steps: 1) open a shared library for writing 2) execute a binary that links that shared library 3) during the binary execution, modify the shared library and save the change result: the 'open_writers' violation measurement is not present in the IMA list. Only binaries executed are protected from writes. For libraries mapped in memory there is the flag MAP_DENYWRITE for this purpose, but according to the output of 'man mmap', the mmap flag is ignored. Since ima_rdwr_violation_check() is now called by process_measurement() the information about if the inode must be measured is already provided by ima_get_action(). Thus the unnecessary function ima_must_measure() has been removed. Changes in v3 (Dmitry Kasatkin): - Violation for MMAP_CHECK function are verified since this patch - Changed patch description a bit Signed-off-by: Roberto Sassu <roberto.sassu@polito.it> Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: fix race condition on ima_rdwr_violation_check and process_measurementRoberto Sassu2014-09-181-21/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes a race condition between two functions that try to access the same inode. Since the i_mutex lock is held and released separately in the two functions, there may be the possibility that a violation is not correctly detected. Suppose there are two processes, A (reader) and B (writer), if the following sequence happens: A: ima_rdwr_violation_check() B: ima_rdwr_violation_check() B: process_measurement() B: starts writing the inode A: process_measurement() the ToMToU violation (a reader may be accessing a content different from that measured, due to a concurrent modification by a writer) will not be detected. To avoid this issue, the violation check and the measurement must be done atomically. This patch fixes the problem by moving the violation check inside process_measurement() when the i_mutex lock is held. Differently from the old code, the violation check is executed also for the MMAP_CHECK hook (other than for FILE_CHECK). This allows to detect ToMToU violations that are possible because shared libraries can be opened for writing while they are in use (according to the output of 'man mmap', the mmap() flag MAP_DENYWRITE is ignored). Changes in v5 (Roberto Sassu): * get iint if action is not zero * exit process_measurement() after the violation check if action is zero * reverse order process_measurement() exit cleanup (Mimi) Changes in v4 (Dmitry Kasatkin): * iint allocation is done before calling ima_rdrw_violation_check() (Suggested-by Mimi) * do not check for violations if the policy does not contain 'measure' rules (done by Roberto Sassu) Changes in v3 (Dmitry Kasatkin): * no violation checking for MMAP_CHECK function in this patch * remove use of filename from violation * removes checking if ima is enabled from ima_rdrw_violation_check * slight style change Suggested-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Roberto Sassu <roberto.sassu@polito.it> Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: added ima_policy_flag variableRoberto Sassu2014-09-171-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces the new variable 'ima_policy_flag', whose bits are set depending on the action of the current policy rules. Only the flags IMA_MEASURE, IMA_APPRAISE and IMA_AUDIT are set. The new variable will be used to improve performance by skipping the unnecessary execution of IMA code if the policy does not contain rules with the above actions. Changes in v6 (Roberto Sassu) * do not check 'ima_initialized' before calling ima_update_policy_flag() in ima_update_policy() (suggested by Dmitry) * calling ima_update_policy_flag() moved to init_ima to co-locate with ima_initialized (Dmitry) * add/revise comments (Mimi) Changes in v5 (Roberto Sassu) * reset IMA_APPRAISE flag in 'ima_policy_flag' if 'ima_appraise' is set to zero (reported by Dmitry) * update 'ima_policy_flag' only if IMA initialization is successful (suggested by Mimi and Dmitry) * check 'ima_policy_flag' instead of 'ima_initialized' (suggested by Mimi and Dmitry) Signed-off-by: Roberto Sassu <roberto.sassu@polito.it> Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: move keyring initialization to ima_init()Dmitry Kasatkin2014-09-171-8/+2
| | | | | | | | | | | | | | | ima_init() is used as a single place for all initializations. Experimental keyring patches used the 'late_initcall' which was co-located with the late_initcall(init_ima). When the late_initcall for the keyring initialization was abandoned, initialization moved to init_ima, though it would be more logical to move it to ima_init, where the rest of the initialization is done. This patch moves the keyring initialization to ima_init() as a preparatory step for loading the keys which will be added to ima_init() in following patches. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: remove usage of filename parameterDmitry Kasatkin2014-09-091-11/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In all cases except ima_bprm_check() the filename was not defined and ima_d_path() was used to find the full path. Unfortunately, the bprm filename is a relative pathname (eg. ./<dir>/filename). ima_bprm_check() selects between bprm->interp and bprm->filename. The following dump demonstrates the differences between using filename and interp. bprm->filename filename: ./foo.sh, pathname: /root/bin/foo.sh filename: ./foo.sh, pathname: /bin/dash bprm->interp filename: ./foo.sh, pathname: /root/bin/foo.sh filename: /bin/sh, pathname: /bin/dash In both cases the pathnames are currently the same. This patch removes usage of filename and interp in favor of d_absolute_path. Changes v3: - 11 extra bytes for "deleted" not needed (Mimi) - purpose "replace relative bprm filename with full pathname" (Mimi) Changes v2: - use d_absolute_path() instead of d_path to work in chroot environments. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: remove unnecessary extra variableDmitry Kasatkin2014-09-091-4/+5
| | | | | | | | 'function' variable value can be changed instead of allocating extra '_func' variable. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: simplify conditional statement to improve performanceDmitry Kasatkin2014-09-091-4/+2
| | | | | | | | | | | Precede bit testing before string comparison makes code faster. Also refactor statement as a single line pointer assignment. Logic is following: we set 'xattr_ptr' to read xattr value when we will do appraisal or in any case when measurement template is other than 'ima'. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: pass 'opened' flag to identify newly created filesDmitry Kasatkin2014-09-091-8/+8
| | | | | | | | | | Empty files and missing xattrs do not guarantee that a file was just created. This patch passes FILE_CREATED flag to IMA to reliably identify new files. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> 3.14+
* ima: provide flag to identify new empty filesDmitry Kasatkin2014-09-081-5/+7
| | | | | | | | | | | | | | | | | | | On ima_file_free(), newly created empty files are not labeled with an initial security.ima value, because the iversion did not change. Commit dff6efc "fs: fix iversion handling" introduced a change in iversion behavior. To verify this change use the shell command: $ (exec >foo) $ getfattr -h -e hex -d -m security foo This patch defines the IMA_NEW_FILE flag. The flag is initially set, when IMA detects that a new file is created, and subsequently checked on the ima_file_free() hook to set the initial security.ima value. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> 3.14+
* ima: add support for measuring and appraising firmwareMimi Zohar2014-07-251-0/+11
| | | | | | | | | | | | | The "security: introduce kernel_fw_from_file hook" patch defined a new security hook to evaluate any loaded firmware that wasn't built into the kernel. This patch defines ima_fw_from_file(), which is called from the new security hook, to measure and/or appraise the loaded firmware's integrity. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Kees Cook <keescook@chromium.org>
* ima: define '.ima' as a builtin 'trusted' keyringMimi Zohar2014-07-171-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Require all keys added to the IMA keyring be signed by an existing trusted key on the system trusted keyring. Changelog v6: - remove ifdef CONFIG_IMA_TRUSTED_KEYRING in C code - Dmitry - update Kconfig dependency and help - select KEYS_DEBUG_PROC_KEYS - Dmitry Changelog v5: - Move integrity_init_keyring() to init_ima() - Dmitry - reset keyring[id] on failure - Dmitry Changelog v1: - don't link IMA trusted keyring to user keyring Changelog: - define stub integrity_init_keyring() function (reported-by Fengguang Wu) - differentiate between regular and trusted keyring names. - replace printk with pr_info (D. Kasatkin) - only make the IMA keyring a trusted keyring (reported-by D. Kastatkin) - define stub integrity_init_keyring() definition based on CONFIG_INTEGRITY_SIGNATURE, not CONFIG_INTEGRITY_ASYMMETRIC_KEYS. (reported-by Jim Davis) Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Acked-by: David Howells <dhowells@redhat.com>
* ima: delay template descriptor lookup until useDmitry Kasatkin2014-07-171-1/+2
| | | | | | | | | | | process_measurement() always calls ima_template_desc_current(), including when an IMA policy has not been defined. This patch delays template descriptor lookup until action is determined. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: remove unnecessary i_mutex locking from ima_rdwr_violation_check()Dmitry Kasatkin2014-07-171-4/+0
| | | | | | | | | | | | | | | Before 2.6.39 inode->i_readcount was maintained by IMA. It was not atomic and protected using spinlock. For 2.6.39, i_readcount was converted to atomic and maintaining was moved VFS layer. Spinlock for some unclear reason was replaced by i_mutex. After analyzing the code, we came to conclusion that i_mutex locking is unnecessary, especially when an IMA policy has not been defined. This patch removes i_mutex locking from ima_rdwr_violation_check(). Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: check inode integrity cache in violation checkDmitry Kasatkin2014-06-121-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | When IMA did not support ima-appraisal, existance of the S_IMA flag clearly indicated that the file was measured. With IMA appraisal S_IMA flag indicates that file was measured and/or appraised. Because of this, when measurement is not enabled by the policy, violations are still reported. To differentiate between measurement and appraisal policies this patch checks the inode integrity cache flags. The IMA_MEASURED flag indicates whether the file was actually measured, while the IMA_MEASURE flag indicates whether the file should be measured. Unfortunately, the IMA_MEASURED flag is reset to indicate the file needs to be re-measured. Thus, this patch checks the IMA_MEASURE flag. This patch limits the false positive violation reports, but does not fix it entirely. The IMA_MEASURE/IMA_MEASURED flags are indications that, at some point in time, the file opened for read was in policy, but might not be in policy now (eg. different uid). Other changes would be needed to further limit false positive violation reports. Changelog: - expanded patch description based on conversation with Roberto (Mimi) Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: prevent unnecessary policy checkingDmitry Kasatkin2014-06-121-9/+4
| | | | | | | | | | | | | | ima_rdwr_violation_check is called for every file openning. The function checks the policy even when violation condition is not met. It causes unnecessary policy checking. This patch does policy checking only if violation condition is met. Changelog: - check writecount is greater than zero (Mimi) Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: audit log files opened with O_DIRECT flagMimi Zohar2014-06-031-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Files are measured or appraised based on the IMA policy. When a file, in policy, is opened with the O_DIRECT flag, a deadlock occurs. The first attempt at resolving this lockdep temporarily removed the O_DIRECT flag and restored it, after calculating the hash. The second attempt introduced the O_DIRECT_HAVELOCK flag. Based on this flag, do_blockdev_direct_IO() would skip taking the i_mutex a second time. The third attempt, by Dmitry Kasatkin, resolves the i_mutex locking issue, by re-introducing the IMA mutex, but uncovered another problem. Reading a file with O_DIRECT flag set, writes directly to userspace pages. A second patch allocates a user-space like memory. This works for all IMA hooks, except ima_file_free(), which is called on __fput() to recalculate the file hash. Until this last issue is addressed, do not 'collect' the measurement for measuring, appraising, or auditing files opened with the O_DIRECT flag set. Based on policy, permit or deny file access. This patch defines a new IMA policy rule option named 'permit_directio'. Policy rules could be defined, based on LSM or other criteria, to permit specific applications to open files with the O_DIRECT flag set. Changelog v1: - permit or deny file access based IMA policy rules Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Cc: <stable@vger.kernel.org>
* ima: return d_name.name if d_path failsDmitry Kasatkin2014-03-071-6/+1
| | | | | | | | | This is a small refactoring so ima_d_path() returns dentry name if path reconstruction fails. It simplifies callers actions and removes code duplication. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* integrity: fix checkpatch errorsDmitry Kasatkin2014-03-071-2/+2
| | | | | | | | | | | | | Between checkpatch changes (eg. sizeof) and inconsistencies between Lindent and checkpatch, unfixed checkpatch errors make it difficult to see new errors. This patch fixes them. Some lines with over 80 chars remained unchanged to improve code readability. The "extern" keyword is removed from internal evm.h to make it consistent with internal ima.h. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: extend the measurement list to include the file signatureMimi Zohar2013-10-311-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | This patch defines a new template called 'ima-sig', which includes the file signature in the template data, in addition to the file's digest and pathname. A template is composed of a set of fields. Associated with each field is an initialization and display function. This patch defines a new template field called 'sig', the initialization function ima_eventsig_init(), and the display function ima_show_template_sig(). This patch modifies the .field_init() function definition to include the 'security.ima' extended attribute and length. Changelog: - remove unused code (Dmitry Kasatkin) - avoid calling ima_write_template_field_data() unnecesarily (Roberto Sassu) - rename DATA_FMT_SIG to DATA_FMT_HEX - cleanup ima_eventsig_init() based on Roberto's comments Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
* ima: enable support for larger default filedata hash algorithmsMimi Zohar2013-10-261-2/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The IMA measurement list contains two hashes - a template data hash and a filedata hash. The template data hash is committed to the TPM, which is limited, by the TPM v1.2 specification, to 20 bytes. The filedata hash is defined as 20 bytes as well. Now that support for variable length measurement list templates was added, the filedata hash is not limited to 20 bytes. This patch adds Kconfig support for defining larger default filedata hash algorithms and replacing the builtin default with one specified on the kernel command line. <uapi/linux/hash_info.h> contains a list of hash algorithms. The Kconfig default hash algorithm is a subset of this list, but any hash algorithm included in the list can be specified at boot, using the 'ima_hash=' kernel command line option. Changelog v2: - update Kconfig Changelog: - support hashes that are configured - use generic HASH_ALGO_ definitions - add Kconfig support - hash_setup must be called only once (Dmitry) - removed trailing whitespaces (Roberto Sassu) Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
* ima: defer determining the appraisal hash algorithm for 'ima' templateRoberto Sassu2013-10-261-1/+5
| | | | | | | | | | | | | | The same hash algorithm should be used for calculating the file data hash for the IMA measurement list, as for appraising the file data integrity. (The appraise hash algorithm is stored in the 'security.ima' extended attribute.) The exception is when the reference file data hash digest, stored in the extended attribute, is larger than the one supported by the template. In this case, the file data hash needs to be calculated twice, once for the measurement list and, again, for appraisal. Signed-off-by: Roberto Sassu <roberto.sassu@polito.it> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: pass the file descriptor to ima_add_violation()Roberto Sassu2013-10-251-3/+2
| | | | | | | | | Pass the file descriptor instead of the inode to ima_add_violation(), to make the latter consistent with ima_store_measurement() in preparation for the new template architecture. Signed-off-by: Roberto Sassu <roberto.sassu@polito.it> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: read and use signature hash algorithmDmitry Kasatkin2013-10-251-2/+9
| | | | | | | | | | | | | | | | | All files on the filesystem, currently, are hashed using the same hash algorithm. In preparation for files from different packages being signed using different hash algorithms, this patch adds support for reading the signature hash algorithm from the 'security.ima' extended attribute and calculates the appropriate file data hash based on it. Changelog: - fix scripts Lindent and checkpatch msgs - Mimi - fix md5 support for older version, which occupied 20 bytes in the xattr, not the expected 16 bytes. Fix the comparison to compare only the first 16 bytes. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: provide support for arbitrary hash algorithmsDmitry Kasatkin2013-10-251-2/+4
| | | | | | | | | | | | | | | | | In preparation of supporting more hash algorithms with larger hash sizes needed for signature verification, this patch replaces the 20 byte sized digest, with a more flexible structure. The new structure includes the hash algorithm, digest size, and digest. Changelog: - recalculate filedata hash for the measurement list, if the signature hash digest size is greater than 20 bytes. - use generic HASH_ALGO_ - make ima_calc_file_hash static - scripts lindent and checkpatch fixes Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: fix script messagesDmitry Kasatkin2013-10-251-5/+5
| | | | | | | Fix checkpatch, lindent, etc, warnings/errors Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* Replace a bunch of file->dentry->d_inode refs with file_inode()David Howells2013-06-291-1/+1
| | | | | | | | | | Replace a bunch of file->dentry->d_inode refs with file_inode(). In __fput(), use file->f_inode instead so as not to be affected by any tricks that file_inode() might grow. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ima: eliminate passing d_name.name to process_measurement()Mimi Zohar2013-04-171-9/+5
| | | | | | | | | | | | | | | | Passing a pointer to the dentry name, as a parameter to process_measurement(), causes a race condition with rename() and is unnecessary, as the dentry name is already accessible via the file parameter. In the normal case, we use the full pathname as provided by brpm->filename, bprm->interp, or ima_d_path(). Only on ima_d_path() failure, do we fallback to using the d_name.name, which points either to external memory or d_iname. Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2013-02-261-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile (part one) from Al Viro: "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent locking violations, etc. The most visible changes here are death of FS_REVAL_DOT (replaced with "has ->d_weak_revalidate()") and a new helper getting from struct file to inode. Some bits of preparation to xattr method interface changes. Misc patches by various people sent this cycle *and* ocfs2 fixes from several cycles ago that should've been upstream right then. PS: the next vfs pile will be xattr stuff." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits) saner proc_get_inode() calling conventions proc: avoid extra pde_put() in proc_fill_super() fs: change return values from -EACCES to -EPERM fs/exec.c: make bprm_mm_init() static ocfs2/dlm: use GFP_ATOMIC inside a spin_lock ocfs2: fix possible use-after-free with AIO ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero target: writev() on single-element vector is pointless export kernel_write(), convert open-coded instances fs: encode_fh: return FILEID_INVALID if invalid fid_type kill f_vfsmnt vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op nfsd: handle vfs_getattr errors in acl protocol switch vfs_getattr() to struct path default SET_PERSONALITY() in linux/elf.h ceph: prepopulate inodes only when request is aborted d_hash_and_lookup(): export, switch open-coded instances 9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate() 9p: split dropping the acls from v9fs_set_create_acl() ...
| * new helper: file_inode(file)Al Viro2013-02-221-2/+2
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | ima: "remove enforce checking duplication" merge fixMimi Zohar2013-02-261-1/+2
| | | | | | | | | | | | | | | | | | | | | | Commit "750943a ima: remove enforce checking duplication" combined the 'in IMA policy' and 'enforcing file integrity' checks. For the non-file, kernel module verification, a specific check for 'enforcing file integrity' was not added. This patch adds the check. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
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