From e9085e0ad38a333012629d815c203155d61ebe7e Mon Sep 17 00:00:00 2001 From: Lakshmi Ramasubramanian Date: Wed, 11 Dec 2019 08:47:06 -0800 Subject: IMA: Add support to limit measuring keys Limit measuring keys to those keys being loaded onto a given set of keyrings only and when the user id (uid) matches if uid is specified in the policy. This patch defines a new IMA policy option namely "keyrings=" that can be used to specify a set of keyrings. If this option is specified in the policy for "measure func=KEY_CHECK" then only the keys loaded onto a keyring given in the "keyrings=" option are measured. If uid is specified in the policy then the key is measured only if the current user id matches the one specified in the policy. Added a new parameter namely "keyring" (name of the keyring) to process_buffer_measurement(). The keyring name is passed to ima_get_action() to determine the required action. ima_match_rules() is updated to check keyring in the policy, if specified, for KEY_CHECK function. Signed-off-by: Lakshmi Ramasubramanian Signed-off-by: Mimi Zohar --- Documentation/ABI/testing/ima_policy | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'Documentation/ABI/testing/ima_policy') diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy index 066d32797500..cd572912c593 100644 --- a/Documentation/ABI/testing/ima_policy +++ b/Documentation/ABI/testing/ima_policy @@ -25,7 +25,7 @@ Description: lsm: [[subj_user=] [subj_role=] [subj_type=] [obj_user=] [obj_role=] [obj_type=]] option: [[appraise_type=]] [template=] [permit_directio] - [appraise_flag=] + [appraise_flag=] [keyrings=] base: func:= [BPRM_CHECK][MMAP_CHECK][CREDS_CHECK][FILE_CHECK][MODULE_CHECK] [FIRMWARE_CHECK] [KEXEC_KERNEL_CHECK] [KEXEC_INITRAMFS_CHECK] @@ -42,6 +42,9 @@ Description: appraise_flag:= [check_blacklist] Currently, blacklist check is only for files signed with appended signature. + keyrings:= list of keyrings + (eg, .builtin_trusted_keys|.ima). Only valid + when action is "measure" and func is KEY_CHECK. template:= name of a defined IMA template type (eg, ima-ng). Only valid when action is "measure". pcr:= decimal value @@ -117,3 +120,8 @@ Description: Example of measure rule using KEY_CHECK to measure all keys: measure func=KEY_CHECK + + Example of measure rule using KEY_CHECK to only measure + keys added to .builtin_trusted_keys or .ima keyring: + + measure func=KEY_CHECK keyrings=.builtin_trusted_keys|.ima -- cgit v1.2.3