keys: Add domain tag to the keyring search criteria

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I49KW1
CVE: NA

--------------------------------

Add keyring_search_tag() version of keyring_search(), that allows to
specify the key domain tag.
Signed-off-by: NKrzysztof Struczynski <krzysztof.struczynski@huawei.com>
Reviewed-by: NZhang Tianxing <zhangtianxing3@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

include/linux/key.h

@@ -417,10 +417,11 @@ extern int restrict_link_reject(struct key *keyring,
 
 extern int keyring_clear(struct key *keyring);
 
-extern key_ref_t keyring_search(key_ref_t keyring,
-				struct key_type *type,
-				const char *description,
-				bool recurse);
+extern key_ref_t keyring_search_tag(key_ref_t keyring,
+				    struct key_type *type,
+				    const char *description,
+				    struct key_tag *domain_tag,
+				    bool recurse);
 
 extern int keyring_add_key(struct key *keyring,
 			   struct key *key);
@@ -430,6 +431,14 @@ extern int keyring_restrict(key_ref_t keyring, const char *type,
 
 extern struct key *key_lookup(key_serial_t id);
 
+static inline key_ref_t keyring_search(key_ref_t keyring,
+				       struct key_type *type,
+				       const char *description,
+				       bool recurse)
+{
+	return keyring_search_tag(keyring, type, description, NULL, recurse);
+}
+
 static inline key_serial_t key_serial(const struct key *key)
 {
 	return key ? key->serial : 0;

security/keys/keyring.c

@@ -925,22 +925,25 @@ key_ref_t keyring_search_rcu(key_ref_t keyring_ref,
 }
 
 /**
- * keyring_search - Search the supplied keyring tree for a matching key
+ * keyring_search_tag - Search the supplied keyring tree for a matching key
  * @keyring: The root of the keyring tree to be searched.
  * @type: The type of keyring we want to find.
  * @description: The name of the keyring we want to find.
+ * @domain_tag: The domain_tag of the key we want to find.
  * @recurse: True to search the children of @keyring also
  *
  * As keyring_search_rcu() above, but using the current task's credentials and
  * type's default matching function and preferred search method.
  */
-key_ref_t keyring_search(key_ref_t keyring,
-			 struct key_type *type,
-			 const char *description,
-			 bool recurse)
+key_ref_t keyring_search_tag(key_ref_t keyring,
+			     struct key_type *type,
+			     const char *description,
+			     struct key_tag *domain_tag,
+			     bool recurse)
 {
 	struct keyring_search_context ctx = {
 		.index_key.type		= type,
+		.index_key.domain_tag   = domain_tag,
 		.index_key.description	= description,
 		.index_key.desc_len	= strlen(description),
 		.cred			= current_cred(),
@@ -968,7 +971,7 @@ key_ref_t keyring_search(key_ref_t keyring,
 		type->match_free(&ctx.match_data);
 	return key;
 }
-EXPORT_SYMBOL(keyring_search);
+EXPORT_SYMBOL(keyring_search_tag);
 
 static struct key_restriction *keyring_restriction_alloc(
 	key_restrict_link_func_t check)