[PATCH 2/4] KEYS: Call the IMA hook to measure keys

[Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx>]

Call the IMA hook from key_create_or_update() function to measure
the payload when a new key is created or an existing key is updated.

This patch adds the call to the IMA hook from key_create_or_update()
function to measure the key on key create or update.

Signed-off-by: Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx>
Cc: David Howells <dhowells@xxxxxxxxxx>
Cc: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
Reported-by: kbuild test robot <lkp@xxxxxxxxx> # ima_asymmetric_keys.c
is built as a kernel module when it is actually not.
Fixes: cb1aa3823c92 ("KEYS: Call the IMA hook to measure keys")
---
 include/linux/ima.h | 14 ++++++++++++++
 security/keys/key.c | 10 ++++++++++
 2 files changed, 24 insertions(+)

diff --git a/include/linux/ima.h b/include/linux/ima.h
index 6d904754d858..f4644c54f648 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h
@@ -101,6 +101,20 @@ static inline void ima_add_kexec_buffer(struct kimage *image)
 {}
 #endif
 
+#ifdef CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS
+extern void ima_post_key_create_or_update(struct key *keyring,
+					  struct key *key,
+					  const void *payload, size_t plen,
+					  unsigned long flags, bool create);
+#else
+static inline void ima_post_key_create_or_update(struct key *keyring,
+						 struct key *key,
+						 const void *payload,
+						 size_t plen,
+						 unsigned long flags,
+						 bool create) {}
+#endif  /* CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS */
+
 #ifdef CONFIG_IMA_APPRAISE
 extern bool is_ima_appraise_enabled(void);
 extern void ima_inode_post_setattr(struct dentry *dentry);
diff --git a/security/keys/key.c b/security/keys/key.c
index 764f4c57913e..718bf7217420 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -13,6 +13,7 @@
 #include <linux/security.h>
 #include <linux/workqueue.h>
 #include <linux/random.h>
+#include <linux/ima.h>
 #include <linux/err.h>
 #include "internal.h"
 
@@ -936,6 +937,9 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 		goto error_link_end;
 	}
 
+	ima_post_key_create_or_update(keyring, key, payload, plen,
+				      flags, true);
+
 	key_ref = make_key_ref(key, is_key_possessed(keyring_ref));
 
 error_link_end:
@@ -965,6 +969,12 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 	}
 
 	key_ref = __key_update(key_ref, &prep);
+
+	if (!IS_ERR(key_ref))
+		ima_post_key_create_or_update(keyring, key,
+					      payload, plen,
+					      flags, false);
+
 	goto error_free_prep;
 }
 EXPORT_SYMBOL(key_create_or_update);
-- 
2.17.1