integrity, KEYS: add a reference to platform keyring

commit 9dc92c4 ("integrity: Define a trusted platform keyring") introduced a .platform keyring for storing preboot keys, used for verifying kernel image signatures. Currently only IMA-appraisal is able to use the keyring to verify kernel images that have their signature stored in xattr. This patch exposes the .platform keyring, making it accessible for verifying PE signed kernel images as well. Suggested-by: Mimi Zohar <[email protected]> Signed-off-by: Kairui Song <[email protected]> Cc: David Howells <[email protected]> [[email protected]: fixed checkpatch errors, squashed with patch fix] Signed-off-by: Mimi Zohar <[email protected]>
josf · Feb 4, 2019 · 219a3e8 · 219a3e8
1 parent 2181e08
commit 219a3e8
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Showing 3 changed files with 21 additions and 0 deletions.
diff --git a/certs/system_keyring.c b/certs/system_keyring.c
@@ -24,6 +24,9 @@ static struct key *builtin_trusted_keys;
 #ifdef CONFIG_SECONDARY_TRUSTED_KEYRING
 static struct key *secondary_trusted_keys;
 #endif
+#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
+static struct key *platform_trusted_keys;
+#endif
 
 extern __initconst const u8 system_certificate_list[];
 extern __initconst const unsigned long system_certificate_list_size;
@@ -266,3 +269,10 @@ int verify_pkcs7_signature(const void *data, size_t len,
 EXPORT_SYMBOL_GPL(verify_pkcs7_signature);
 
 #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */
+
+#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
+void __init set_platform_trusted_keys(struct key *keyring)
+{
+	platform_trusted_keys = keyring;
+}
+#endif
diff --git a/include/keys/system_keyring.h b/include/keys/system_keyring.h
@@ -61,5 +61,13 @@ static inline struct key *get_ima_blacklist_keyring(void)
 }
 #endif /* CONFIG_IMA_BLACKLIST_KEYRING */
 
+#if defined(CONFIG_INTEGRITY_PLATFORM_KEYRING) && \
+	defined(CONFIG_SYSTEM_TRUSTED_KEYRING)
+extern void __init set_platform_trusted_keys(struct key *keyring);
+#else
+static inline void set_platform_trusted_keys(struct key *keyring)
+{
+}
+#endif
 
 #endif /* _KEYS_SYSTEM_KEYRING_H */
diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c
@@ -87,6 +87,9 @@ static int __integrity_init_keyring(const unsigned int id, key_perm_t perm,
 		pr_info("Can't allocate %s keyring (%d)\n",
 			keyring_name[id], err);
 		keyring[id] = NULL;
+	} else {
+		if (id == INTEGRITY_KEYRING_PLATFORM)
+			set_platform_trusted_keys(keyring[id]);
 	}
 
 	return err;