diff options
Diffstat (limited to 'Documentation/ABI/testing/ima_policy')
-rw-r--r-- | Documentation/ABI/testing/ima_policy | 45 |
1 files changed, 42 insertions, 3 deletions
diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy index 839fab811b18..db17fc8a0c9f 100644 --- a/Documentation/ABI/testing/ima_policy +++ b/Documentation/ABI/testing/ima_policy @@ -27,8 +27,9 @@ Description: [fowner=] [fgroup=]] lsm: [[subj_user=] [subj_role=] [subj_type=] [obj_user=] [obj_role=] [obj_type=]] - option: [[appraise_type=]] [template=] [permit_directio] - [appraise_flag=] [appraise_algos=] [keyrings=] + option: [digest_type=] [template=] [permit_directio] + [appraise_type=] [appraise_flag=] + [appraise_algos=] [keyrings=] base: func:= [BPRM_CHECK][MMAP_CHECK][CREDS_CHECK][FILE_CHECK][MODULE_CHECK] [FIRMWARE_CHECK] @@ -47,10 +48,21 @@ Description: fgroup:= decimal value lsm: are LSM specific option: - appraise_type:= [imasig] [imasig|modsig] + appraise_type:= [imasig] | [imasig|modsig] | [sigv3] + where 'imasig' is the original or the signature + format v2. + where 'modsig' is an appended signature, + where 'sigv3' is the signature format v3. (Currently + limited to fsverity digest based signatures + stored in security.ima xattr. Requires + specifying "digest_type=verity" first.) + appraise_flag:= [check_blacklist] Currently, blacklist check is only for files signed with appended signature. + digest_type:= verity + Require fs-verity's file digest instead of the + regular IMA file hash. keyrings:= list of keyrings (eg, .builtin_trusted_keys|.ima). Only valid when action is "measure" and func is KEY_CHECK. @@ -149,3 +161,30 @@ Description: security.ima xattr of a file: appraise func=SETXATTR_CHECK appraise_algos=sha256,sha384,sha512 + + Example of a 'measure' rule requiring fs-verity's digests + with indication of type of digest in the measurement list. + + measure func=FILE_CHECK digest_type=verity \ + template=ima-ngv2 + + Example of 'measure' and 'appraise' rules requiring fs-verity + signatures (format version 3) stored in security.ima xattr. + + The 'measure' rule specifies the 'ima-sigv3' template option, + which includes the indication of type of digest and the file + signature in the measurement list. + + measure func=BPRM_CHECK digest_type=verity \ + template=ima-sigv3 + + + The 'appraise' rule specifies the type and signature format + version (sigv3) required. + + appraise func=BPRM_CHECK digest_type=verity \ + appraise_type=sigv3 + + All of these policy rules could, for example, be constrained + either based on a filesystem's UUID (fsuuid) or based on LSM + labels. |