[RFC PATCH 16/20] KEYS: Remove KEY_FLAG_TRUSTED and KEY_ALLOC_TRUSTED [ver #2]

[David Howells <dhowells@redhat.com>]

Remove KEY_FLAG_TRUSTED and KEY_ALLOC_TRUSTED as they're no longer
meaningful.  Also we can drop the trusted flag from the preparse structure.

Given this, we no longer need to pass the key flags through to
restrict_link().

Further, we can now get rid of keyring_restrict_trusted_only() also.

Signed-off-by: David Howells <dhowells@redhat.com>
---

 certs/system_keyring.c        |    2 --
 include/keys/system_keyring.h |    1 -
 include/linux/key-type.h      |    1 -
 include/linux/key.h           |   20 +++++---------------
 security/integrity/digsig.c   |    4 +---
 security/keys/key.c           |   11 ++---------
 security/keys/keyring.c       |   28 +---------------------------
 7 files changed, 9 insertions(+), 58 deletions(-)

diff --git a/certs/system_keyring.c b/certs/system_keyring.c
index 6e069246c168..5e76121d4cc2 100644
--- a/certs/system_keyring.c
+++ b/certs/system_keyring.c
@@ -31,7 +31,6 @@ extern __initconst const unsigned long system_certificate_list_size;
  */
 int restrict_link_by_system_trusted(struct key *keyring,
 				    const struct key_type *type,
-				    unsigned long flags,
 				    const union key_payload *payload)
 {
 	return public_key_restrict_link(system_trusted_keyring, type, payload);
@@ -96,7 +95,6 @@ static __init int load_system_certificate_list(void)
 					   ((KEY_POS_ALL & ~KEY_POS_SETATTR) |
 					   KEY_USR_VIEW | KEY_USR_READ),
 					   KEY_ALLOC_NOT_IN_QUOTA |
-					   KEY_ALLOC_TRUSTED |
 					   KEY_ALLOC_BUILT_IN |
 					   KEY_ALLOC_BYPASS_RESTRICTION);
 		if (IS_ERR(key)) {
diff --git a/include/keys/system_keyring.h b/include/keys/system_keyring.h
index 28ca2d824554..615244b1e276 100644
--- a/include/keys/system_keyring.h
+++ b/include/keys/system_keyring.h
@@ -18,7 +18,6 @@
 
 extern int restrict_link_by_system_trusted(struct key *keyring,
 					   const struct key_type *type,
-					   unsigned long flags,
 					   const union key_payload *payload);
 #endif
 
diff --git a/include/linux/key-type.h b/include/linux/key-type.h
index 7463355a198b..eaee981c5558 100644
--- a/include/linux/key-type.h
+++ b/include/linux/key-type.h
@@ -45,7 +45,6 @@ struct key_preparsed_payload {
 	size_t		datalen;	/* Raw datalen */
 	size_t		quotalen;	/* Quota length for proposed payload */
 	time_t		expiry;		/* Expiry time of key */
-	bool		trusted;	/* True if key is trusted */
 };
 
 typedef int (*request_key_actor_t)(struct key_construction *key,
diff --git a/include/linux/key.h b/include/linux/key.h
index c331b8bed035..9b885ba3ba63 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -173,10 +173,9 @@ struct key {
 #define KEY_FLAG_NEGATIVE	5	/* set if key is negative */
 #define KEY_FLAG_ROOT_CAN_CLEAR	6	/* set if key can be cleared by root without permission */
 #define KEY_FLAG_INVALIDATED	7	/* set if key has been invalidated */
-#define KEY_FLAG_TRUSTED	8	/* set if key is trusted */
-#define KEY_FLAG_BUILTIN	9	/* set if key is built in to the kernel */
-#define KEY_FLAG_ROOT_CAN_INVAL	10	/* set if key can be invalidated by root without permission */
-#define KEY_FLAG_KEEP		11	/* set if key should not be removed */
+#define KEY_FLAG_BUILTIN	8	/* set if key is built in to the kernel */
+#define KEY_FLAG_ROOT_CAN_INVAL	9	/* set if key can be invalidated by root without permission */
+#define KEY_FLAG_KEEP		10	/* set if key should not be removed */
 
 	/* the key type and key description string
 	 * - the desc is used to match a key against search criteria
@@ -217,7 +216,6 @@ struct key {
 	 */
 	int (*restrict_link)(struct key *keyring,
 			     const struct key_type *type,
-			     unsigned long flags,
 			     const union key_payload *payload);
 };
 
@@ -229,16 +227,14 @@ extern struct key *key_alloc(struct key_type *type,
 			     unsigned long flags,
 			     int (*restrict_link)(struct key *,
 						  const struct key_type *,
-						  unsigned long,
 						  const union key_payload *));
 
 
 #define KEY_ALLOC_IN_QUOTA		0x0000	/* add to quota, reject if would overrun */
 #define KEY_ALLOC_QUOTA_OVERRUN		0x0001	/* add to quota, permit even if overrun */
 #define KEY_ALLOC_NOT_IN_QUOTA		0x0002	/* not in quota */
-#define KEY_ALLOC_TRUSTED		0x0004	/* Key should be flagged as trusted */
-#define KEY_ALLOC_BUILT_IN		0x0008	/* Key is built into kernel */
-#define KEY_ALLOC_BYPASS_RESTRICTION	0x0010	/* Override the check on restricted keyrings */
+#define KEY_ALLOC_BUILT_IN		0x0004	/* Key is built into kernel */
+#define KEY_ALLOC_BYPASS_RESTRICTION	0x0008	/* Override the check on restricted keyrings */
 
 extern void key_revoke(struct key *key);
 extern void key_invalidate(struct key *key);
@@ -309,15 +305,9 @@ extern struct key *keyring_alloc(const char *description, kuid_t uid, kgid_t gid
 				 unsigned long flags,
 				 int (*restrict_link)(struct key *,
 						      const struct key_type *,
-						      unsigned long,
 						      const union key_payload *),
 				 struct key *dest);
 
-extern int keyring_restrict_trusted_only(struct key *keyring,
-					 const struct key_type *type,
-					 unsigned long,
-					 const union key_payload *payload);
-
 extern int keyring_clear(struct key *keyring);
 
 extern key_ref_t keyring_search(key_ref_t keyring,
diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c
index fee9b5b08b01..464d25e698ec 100644
--- a/security/integrity/digsig.c
+++ b/security/integrity/digsig.c
@@ -50,12 +50,11 @@ static bool init_keyring __initdata;
  */
 static int restrict_link_by_ima_mok(struct key *keyring,
 				    const struct key_type *type,
-				    unsigned long flags,
 				    const union key_payload *payload)
 {
 	int ret;
 
-	ret = restrict_link_by_system_trusted(keyring, type, flags, payload);
+	ret = restrict_link_by_system_trusted(keyring, type, payload);
 	if (ret != -ENOKEY)
 		return ret;
 
@@ -96,7 +95,6 @@ int __init integrity_init_keyring(const unsigned int id)
 {
 	int (*restrict_link)(struct key *,
 			     const struct key_type *,
-			     unsigned long,
 			     const union key_payload *) = NULL;
 	const struct cred *cred = current_cred();
 	int err = 0;
diff --git a/security/keys/key.c b/security/keys/key.c
index 23b271b1834d..f61e2fd5c0c5 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -227,7 +227,6 @@ struct key *key_alloc(struct key_type *type, const char *desc,
 		      key_perm_t perm, unsigned long flags,
 		      int (*restrict_link)(struct key *,
 					   const struct key_type *,
-					   unsigned long,
 					   const union key_payload *))
 {
 	struct key_user *user = NULL;
@@ -300,8 +299,6 @@ struct key *key_alloc(struct key_type *type, const char *desc,
 
 	if (!(flags & KEY_ALLOC_NOT_IN_QUOTA))
 		key->flags |= 1 << KEY_FLAG_IN_QUOTA;
-	if (flags & KEY_ALLOC_TRUSTED)
-		key->flags |= 1 << KEY_FLAG_TRUSTED;
 	if (flags & KEY_ALLOC_BUILT_IN)
 		key->flags |= 1 << KEY_FLAG_BUILTIN;
 
@@ -503,7 +500,7 @@ int key_instantiate_and_link(struct key *key,
 	if (keyring) {
 		if (keyring->restrict_link) {
 			ret = keyring->restrict_link(keyring, key->type,
-						     key->flags, &prep.payload);
+						     &prep.payload);
 			if (ret < 0)
 				goto error;
 		}
@@ -810,7 +807,6 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 	int ret;
 	int (*restrict_link)(struct key *,
 			     const struct key_type *,
-			     unsigned long,
 			     const union key_payload *) = NULL;
 
 	/* look up the key type to see if it's one of the registered kernel
@@ -842,7 +838,6 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 	prep.data = payload;
 	prep.datalen = plen;
 	prep.quotalen = index_key.type->def_datalen;
-	prep.trusted = flags & KEY_ALLOC_TRUSTED;
 	prep.expiry = TIME_T_MAX;
 	if (index_key.type->preparse) {
 		ret = index_key.type->preparse(&prep);
@@ -859,9 +854,7 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 	index_key.desc_len = strlen(index_key.description);
 
 	if (restrict_link) {
-		unsigned long kflags = prep.trusted ? KEY_FLAG_TRUSTED : 0;
-		ret = restrict_link(keyring,
-				    index_key.type, kflags, &prep.payload);
+		ret = restrict_link(keyring, index_key.type, &prep.payload);
 		if (ret < 0) {
 			key_ref = ERR_PTR(ret);
 			goto error_free_prep;
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index ea023ca6d217..68f02cd4e921 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -494,7 +494,6 @@ struct key *keyring_alloc(const char *description, kuid_t uid, kgid_t gid,
 			  unsigned long flags,
 			  int (*restrict_link)(struct key *,
 					       const struct key_type *,
-					       unsigned long,
 					       const union key_payload *),
 			  struct key *dest)
 {
@@ -515,30 +514,6 @@ struct key *keyring_alloc(const char *description, kuid_t uid, kgid_t gid,
 }
 EXPORT_SYMBOL(keyring_alloc);
 
-/**
- * keyring_restrict_trusted_only - Restrict additions to a keyring to trusted keys only
- * @keyring: The keyring being added to.
- * @type: The type of key being added.
- * @flags: The key flags.
- * @payload: The payload of the key intended to be added.
- *
- * Reject the addition of any links to a keyring that point to keys that aren't
- * marked as being trusted.  It can be overridden by passing
- * KEY_ALLOC_BYPASS_RESTRICTION to key_instantiate_and_link() when adding a key
- * to a keyring.
- *
- * This is meant to be passed as the restrict_link parameter to
- * keyring_alloc().
- */
-int keyring_restrict_trusted_only(struct key *keyring,
-				  const struct key_type *type,
-				  unsigned long flags,
-				  const union key_payload *payload)
-{
-	
-	return flags & KEY_FLAG_TRUSTED ? 0 : -EPERM;
-}
-
 /*
  * By default, we keys found by getting an exact match on their descriptions.
  */
@@ -1227,8 +1202,7 @@ static int __key_link_check_restriction(struct key *keyring, struct key *key)
 {
 	if (!keyring->restrict_link)
 		return 0;
-	return keyring->restrict_link(keyring,
-				      key->type, key->flags, &key->payload);
+	return keyring->restrict_link(keyring, key->type, &key->payload);
 }
 
 /**