[PATCH v6 3/3] KEYS: Call the IMA hook to measure keys

[Lakshmi Ramasubramanian]

Call the IMA hook from key_create_or_update function to measure
the key 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 at linux.microsoft.com>
---
 include/linux/ima.h | 13 +++++++++++++
 security/keys/key.c |  9 +++++++++
 2 files changed, 22 insertions(+)

diff --git a/include/linux/ima.h b/include/linux/ima.h
index 6d904754d858..ec5afe319ab7 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h
@@ -25,6 +25,12 @@ extern int ima_post_read_file(struct file *file, void *buf, loff_t size,
 extern void ima_post_path_mknod(struct dentry *dentry);
 extern void ima_kexec_cmdline(const void *buf, int size);
 
+#ifdef CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS
+extern void ima_post_key_create_or_update(struct key *keyring,
+					  struct key *key,
+					  unsigned long flags, bool create);
+#endif
+
 #ifdef CONFIG_IMA_KEXEC
 extern void ima_add_kexec_buffer(struct kimage *image);
 #endif
@@ -101,6 +107,13 @@ static inline void ima_add_kexec_buffer(struct kimage *image)
 {}
 #endif
 
+#ifndef CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS
+static inline void ima_post_key_create_or_update(struct key *keyring,
+						 struct key *key,
+						 unsigned long flags,
+						 bool create) {}
+#endif
+
 #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..9782d4d046fd 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;
 	}
 
+	/* let the ima module know about the created key. */
+	ima_post_key_create_or_update(keyring, key, flags, true);
+
 	key_ref = make_key_ref(key, is_key_possessed(keyring_ref));
 
 error_link_end:
@@ -965,6 +969,11 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 	}
 
 	key_ref = __key_update(key_ref, &prep);
+
+	/* let the ima module know about the updated key. */
+	if (!IS_ERR(key_ref))
+		ima_post_key_create_or_update(keyring, key, flags, false);
+
 	goto error_free_prep;
 }
 EXPORT_SYMBOL(key_create_or_update);
-- 
2.17.1