[PATCH v1 3/6] KEYS: ima hook to measure builtin_trusted_keys

[Lakshmi Ramasubramanian]

Add a new ima hook to measure keys added to builtin_trusted_keys
keyring.

Updated ima_match_rules function to handle the new ima hook.
This is used to determine if ima policy requires measurement
of keys added to builtin_trusted_keys keyring.

Signed-off-by: Lakshmi Ramasubramanian <nra...@linux.microsoft.com>
---
 Documentation/ABI/testing/ima_policy | 1 +
 security/integrity/ima/ima.h         | 1 +
 security/integrity/ima/ima_api.c     | 1 +
 security/integrity/ima/ima_policy.c  | 5 ++++-
 4 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/Documentation/ABI/testing/ima_policy 
b/Documentation/ABI/testing/ima_policy
index fc376a323908..25566c74e679 100644
--- a/Documentation/ABI/testing/ima_policy
+++ b/Documentation/ABI/testing/ima_policy
@@ -29,6 +29,7 @@ Description:
                                [FIRMWARE_CHECK]
                                [KEXEC_KERNEL_CHECK] [KEXEC_INITRAMFS_CHECK]
                                [KEXEC_CMDLINE]
+                               [BUILTIN_TRUSTED_KEYS]
                        mask:= [[^]MAY_READ] [[^]MAY_WRITE] [[^]MAY_APPEND]
                               [[^]MAY_EXEC]
                        fsmagic:= hex value
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index b6847ee1f47a..0d2908036882 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -189,6 +189,7 @@ static inline unsigned long ima_hash_key(u8 *digest)
        hook(KEXEC_INITRAMFS_CHECK)     \
        hook(POLICY_CHECK)              \
        hook(KEXEC_CMDLINE)             \
+       hook(BUILTIN_TRUSTED_KEYS)      \
        hook(MAX_CHECK)
 #define __ima_hook_enumify(ENUM)       ENUM,
 
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index f614e22bf39f..cc04706b7e7a 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -175,6 +175,7 @@ void ima_add_violation(struct file *file, const unsigned 
char *filename,
  *     subj,obj, and type: are LSM specific.
  *     func: FILE_CHECK | BPRM_CHECK | CREDS_CHECK | MMAP_CHECK | MODULE_CHECK
  *     | KEXEC_CMDLINE
+ *     | BUILTIN_TRUSTED_KEYS
  *     mask: contains the permission mask
  *     fsmagic: hex value
  *
diff --git a/security/integrity/ima/ima_policy.c 
b/security/integrity/ima/ima_policy.c
index 6df7f641ff66..944636076152 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -370,7 +370,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule, 
struct inode *inode,
 {
        int i;
 
-       if (func == KEXEC_CMDLINE) {
+       if ((func == KEXEC_CMDLINE) || (func == BUILTIN_TRUSTED_KEYS)) {
                if ((rule->flags & IMA_FUNC) && (rule->func == func))
                        return true;
                return false;
@@ -959,6 +959,9 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry 
*entry)
                                entry->func = POLICY_CHECK;
                        else if (strcmp(args[0].from, "KEXEC_CMDLINE") == 0)
                                entry->func = KEXEC_CMDLINE;
+                       else if (strcmp(args[0].from,
+                                       "BUILTIN_TRUSTED_KEYS") == 0)
+                               entry->func = BUILTIN_TRUSTED_KEYS;
                        else
                                result = -EINVAL;
                        if (!result)
-- 
2.17.1