On Jan 15, 2024 Roberto Sassu <roberto.sassu@xxxxxxxxxxxxxxx> wrote: > > Move hardcoded IMA function calls (not appraisal-specific functions) from > various places in the kernel to the LSM infrastructure, by introducing a > new LSM named 'ima' (at the end of the LSM list and always enabled like > 'integrity'). > > Having IMA before EVM in the Makefile is sufficient to preserve the > relative order of the new 'ima' LSM in respect to the upcoming 'evm' LSM, > and thus the order of IMA and EVM function calls as when they were > hardcoded. > > Make moved functions as static (except ima_post_key_create_or_update(), > which is not in ima_main.c), and register them as implementation of the > respective hooks in the new function init_ima_lsm(). > > Select CONFIG_SECURITY_PATH, to ensure that the path-based LSM hook > path_post_mknod is always available and ima_post_path_mknod() is always > executed to mark files as new, as before the move. > > A slight difference is that IMA and EVM functions registered for the > inode_post_setattr, inode_post_removexattr, path_post_mknod, > inode_post_create_tmpfile, inode_post_set_acl and inode_post_remove_acl > won't be executed for private inodes. Since those inodes are supposed to be > fs-internal, they should not be of interest of IMA or EVM. The S_PRIVATE > flag is used for anonymous inodes, hugetlbfs, reiserfs xattrs, XFS scrub > and kernel-internal tmpfs files. > > Conditionally register ima_post_key_create_or_update() if > CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS is enabled. Also, conditionally register > ima_kernel_module_request() if CONFIG_INTEGRITY_ASYMMETRIC_KEYS is enabled. > > Finally, add the LSM_ID_IMA case in lsm_list_modules_test.c. > > Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx> > Acked-by: Chuck Lever <chuck.lever@xxxxxxxxxx> > Acked-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx> > --- > fs/file_table.c | 2 - > fs/namei.c | 6 - > fs/nfsd/vfs.c | 7 -- > fs/open.c | 1 - > include/linux/ima.h | 104 ------------------ > include/uapi/linux/lsm.h | 1 + > security/integrity/Makefile | 1 + > security/integrity/ima/Kconfig | 1 + > security/integrity/ima/ima.h | 6 + > security/integrity/ima/ima_main.c | 78 +++++++++---- > security/integrity/integrity.h | 1 + > security/keys/key.c | 9 +- > security/security.c | 63 ++--------- > .../selftests/lsm/lsm_list_modules_test.c | 3 + > 14 files changed, 83 insertions(+), 200 deletions(-) Acked-by: Paul Moore <paul@xxxxxxxxxxxxxx> -- paul-moore.com
