[PATCH v4 06/12] KEYS: add a reference to mok keyring

[Eric Snowberg <eric.snowberg@oracle.com>]

Expose the .mok keyring created in integrity code by adding
a reference.  This makes the mok keyring accessible for keyring
restrictions in the future.

Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com>
---
v2: Initial version
v3: set_mok_trusted_keys only available when secondary is enabled
v4: Moved code under CONFIG_INTEGRITY_MOK_KEYRING
---
 certs/system_keyring.c        | 9 +++++++++
 include/keys/system_keyring.h | 8 ++++++++
 2 files changed, 17 insertions(+)

diff --git a/certs/system_keyring.c b/certs/system_keyring.c
index 692365dee2bd..94af3fe107b4 100644
--- a/certs/system_keyring.c
+++ b/certs/system_keyring.c
@@ -22,6 +22,9 @@ static struct key *builtin_trusted_keys;
 #ifdef CONFIG_SECONDARY_TRUSTED_KEYRING
 static struct key *secondary_trusted_keys;
 #endif
+#ifdef CONFIG_INTEGRITY_MOK_KEYRING
+static struct key *mok_trusted_keys;
+#endif
 #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
 static struct key *platform_trusted_keys;
 #endif
@@ -91,6 +94,12 @@ static __init struct key_restriction *get_builtin_and_secondary_restriction(void
 	return restriction;
 }
 #endif
+#ifdef CONFIG_INTEGRITY_MOK_KEYRING
+void __init set_mok_trusted_keys(struct key *keyring)
+{
+	mok_trusted_keys = keyring;
+}
+#endif
 
 /*
  * Create the trusted keyrings
diff --git a/include/keys/system_keyring.h b/include/keys/system_keyring.h
index 6acd3cf13a18..059e32e36b3a 100644
--- a/include/keys/system_keyring.h
+++ b/include/keys/system_keyring.h
@@ -38,6 +38,14 @@ extern int restrict_link_by_builtin_and_secondary_trusted(
 #define restrict_link_by_builtin_and_secondary_trusted restrict_link_by_builtin_trusted
 #endif
 
+#ifdef CONFIG_INTEGRITY_MOK_KEYRING
+extern void __init set_mok_trusted_keys(struct key *keyring);
+#else
+static inline void __init set_mok_trusted_keys(struct key *keyring)
+{
+}
+#endif
+
 extern struct pkcs7_message *pkcs7;
 #ifdef CONFIG_SYSTEM_BLACKLIST_KEYRING
 extern int mark_hash_blacklisted(const char *hash);
-- 
2.18.4