KEYS: Generalise x509_request_asymmetric_key()

Generalise x509_request_asymmetric_key().  It doesn't really have any
dependencies on X.509 features as it uses generalised IDs and the
public_key structs that contain data extracted from X.509.

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

crypto/asymmetric_keys/pkcs7_trust.c

@@ -51,9 +51,8 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
 		/* Look to see if this certificate is present in the trusted
 		 * keys.
 		 */
-		key = x509_request_asymmetric_key(trust_keyring,
-						  x509->id, x509->skid,
-						  false);
+		key = find_asymmetric_key(trust_keyring,
+					  x509->id, x509->skid, false);
 		if (!IS_ERR(key)) {
 			/* One of the X.509 certificates in the PKCS#7 message
 			 * is apparently the same as one we already trust.
@@ -84,10 +83,10 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
 	 * trusted keys.
 	 */
 	if (last && (last->sig->auth_ids[0] || last->sig->auth_ids[1])) {
-		key = x509_request_asymmetric_key(trust_keyring,
-						  last->sig->auth_ids[0],
-						  last->sig->auth_ids[1],
-						  false);
+		key = find_asymmetric_key(trust_keyring,
+					  last->sig->auth_ids[0],
+					  last->sig->auth_ids[1],
+					  false);
 		if (!IS_ERR(key)) {
 			x509 = last;
 			pr_devel("sinfo %u: Root cert %u signer is key %x\n",
@@ -101,10 +100,8 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
 	/* As a last resort, see if we have a trusted public key that matches
 	 * the signed info directly.
 	 */
-	key = x509_request_asymmetric_key(trust_keyring,
-					  sinfo->sig->auth_ids[0],
-					  NULL,
-					  false);
+	key = find_asymmetric_key(trust_keyring,
+				  sinfo->sig->auth_ids[0], NULL, false);
 	if (!IS_ERR(key)) {
 		pr_devel("sinfo %u: Direct signer is key %x\n",
 			 sinfo->index, key_serial(key));