diff options
| author | Florent Revest <revest@google.com> | 2020-01-13 12:42:44 +0300 |
|---|---|---|
| committer | Mimi Zohar <zohar@linux.ibm.com> | 2020-01-22 23:22:51 +0300 |
| commit | 6beea7afcc72b86986080ea1d228a42f2000f2a9 (patch) | |
| tree | f4dcbae6ca30de7fd291c6e84ee384bcfc0945d9 /include/linux/ima.h | |
| parent | 5350ceb0b7befba9f607fd4c09b1a424e117fe1c (diff) | |
| download | linux-6beea7afcc72b86986080ea1d228a42f2000f2a9.tar.xz | |
ima: add the ability to query the cached hash of a given file
This allows other parts of the kernel (perhaps a stacked LSM allowing
system monitoring, eg. the proposed KRSI LSM [1]) to retrieve the hash
of a given file from IMA if it's present in the iint cache.
It's true that the existence of the hash means that it's also in the
audit logs or in /sys/kernel/security/ima/ascii_runtime_measurements,
but it can be difficult to pull that information out for every
subsequent exec. This is especially true if a given host has been up
for a long time and the file was first measured a long time ago.
It should be kept in mind that this function gives access to cached
entries which can be removed, for instance on security_inode_free().
This is based on Peter Moody's patch:
https://sourceforge.net/p/linux-ima/mailman/message/33036180/
[1] https://lkml.org/lkml/2019/9/10/393
Signed-off-by: Florent Revest <revest@google.com>
Reviewed-by: KP Singh <kpsingh@chromium.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Diffstat (limited to 'include/linux/ima.h')
| -rw-r--r-- | include/linux/ima.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/ima.h b/include/linux/ima.h index f4644c54f648..1659217e9b60 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -23,6 +23,7 @@ extern int ima_read_file(struct file *file, enum kernel_read_file_id id); extern int ima_post_read_file(struct file *file, void *buf, loff_t size, enum kernel_read_file_id id); extern void ima_post_path_mknod(struct dentry *dentry); +extern int ima_file_hash(struct file *file, char *buf, size_t buf_size); extern void ima_kexec_cmdline(const void *buf, int size); #ifdef CONFIG_IMA_KEXEC @@ -91,6 +92,11 @@ static inline void ima_post_path_mknod(struct dentry *dentry) return; } +static inline int ima_file_hash(struct file *file, char *buf, size_t buf_size) +{ + return -EOPNOTSUPP; +} + static inline void ima_kexec_cmdline(const void *buf, int size) {} #endif /* CONFIG_IMA */ |