upstream: Request RSA-SHA2 signatures for

rsa-sha2-{256|512}-cert-v01@openssh.com cert algorithms; ok markus@

OpenBSD-Commit-ID: afc6f7ca216ccd821656d1c911d2a3deed685033
diff --git a/authfd.c b/authfd.c
index cc9c650..95348ab 100644
--- a/authfd.c
+++ b/authfd.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: authfd.c,v 1.112 2018/11/30 02:24:52 djm Exp $ */
+/* $OpenBSD: authfd.c,v 1.113 2018/12/27 23:02:11 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -327,10 +327,12 @@
 static u_int
 agent_encode_alg(const struct sshkey *key, const char *alg)
 {
-	if (alg != NULL && key->type == KEY_RSA) {
-		if (strcmp(alg, "rsa-sha2-256") == 0)
+	if (alg != NULL && sshkey_type_plain(key->type) == KEY_RSA) {
+		if (strcmp(alg, "rsa-sha2-256") == 0 ||
+		    strcmp(alg, "rsa-sha2-256-cert-v01@openssh.com") == 0)
 			return SSH_AGENT_RSA_SHA2_256;
-		else if (strcmp(alg, "rsa-sha2-512") == 0)
+		if (strcmp(alg, "rsa-sha2-512") == 0 ||
+		    strcmp(alg, "rsa-sha2-512-cert-v01@openssh.com") == 0)
 			return SSH_AGENT_RSA_SHA2_512;
 	}
 	return 0;