diff --git a/ssh-keyscan.1 b/ssh-keyscan.1
index 6bbc480cd..12eb5810b 100644
--- a/ssh-keyscan.1
+++ b/ssh-keyscan.1
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: ssh-keyscan.1,v 1.36 2014/08/30 15:33:50 sobrado Exp $
+.\"	$OpenBSD: ssh-keyscan.1,v 1.37 2015/11/08 22:30:20 djm Exp $
 .\"
 .\" Copyright 1995, 1996 by David Mazieres <dm@lcs.mit.edu>.
 .\"
@@ -6,7 +6,7 @@
 .\" permitted provided that due credit is given to the author and the
 .\" OpenBSD project by leaving this copyright notice intact.
 .\"
-.Dd $Mdocdate: August 30 2014 $
+.Dd $Mdocdate: November 8 2015 $
 .Dt SSH-KEYSCAN 1
 .Os
 .Sh NAME
@@ -15,7 +15,7 @@
 .Sh SYNOPSIS
 .Nm ssh-keyscan
 .Bk -words
-.Op Fl 46Hv
+.Op Fl 46Hcv
 .Op Fl f Ar file
 .Op Fl p Ar port
 .Op Fl T Ar timeout
@@ -54,6 +54,8 @@ to use IPv4 addresses only.
 Forces
 .Nm
 to use IPv6 addresses only.
+.It Fl c
+Request certificates from target hosts instead of plain keys.
 .It Fl f Ar file
 Read hosts or
 .Dq addrlist namelist
diff --git a/ssh-keyscan.c b/ssh-keyscan.c
index 7db0e10e5..0e5ca609a 100644
--- a/ssh-keyscan.c
+++ b/ssh-keyscan.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-keyscan.c,v 1.102 2015/10/24 22:56:19 djm Exp $ */
+/* $OpenBSD: ssh-keyscan.c,v 1.103 2015/11/08 22:30:20 djm Exp $ */
 /*
  * Copyright 1995, 1996 by David Mazieres <dm@lcs.mit.edu>.
  *
@@ -60,6 +60,7 @@ int ssh_port = SSH_DEFAULT_PORT;
 #define KT_ECDSA	8
 #define KT_ED25519	16
 
+int get_cert = 0;
 int get_keytypes = KT_RSA|KT_ECDSA|KT_ED25519;
 
 int hash_hosts = 0;		/* Hash hostname on output */
@@ -267,11 +268,32 @@ keygrab_ssh2(con *c)
 	int r;
 
 	enable_compat20();
-	myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
-	    c->c_keytype == KT_DSA ?  "ssh-dss" :
-	    (c->c_keytype == KT_RSA ? "ssh-rsa" :
-	    (c->c_keytype == KT_ED25519 ? "ssh-ed25519" :
-	    "ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521"));
+	switch (c->c_keytype) {
+	case KT_DSA:
+		myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = get_cert ?
+		    "ssh-dss-cert-v01@openssh.com" : "ssh-dss";
+		break;
+	case KT_RSA:
+		myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = get_cert ?
+		    "ssh-rsa-cert-v01@openssh.com" : "ssh-rsa";
+		break;
+	case KT_ED25519:
+		myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = get_cert ?
+		    "ssh-ed25519-cert-v01@openssh.com" : "ssh-ed25519";
+		break;
+	case KT_ECDSA:
+		myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = get_cert ?
+		    "ecdsa-sha2-nistp256-cert-v01@openssh.com,"
+		    "ecdsa-sha2-nistp384-cert-v01@openssh.com,"
+		    "ecdsa-sha2-nistp521-cert-v01@openssh.com" :
+		    "ecdsa-sha2-nistp256,"
+		    "ecdsa-sha2-nistp384,"
+		    "ecdsa-sha2-nistp521";
+		break;
+	default:
+		fatal("unknown key type %d", c->c_keytype);
+		break;
+	}
 	if ((r = kex_setup(c->c_ssh, myproposal)) != 0) {
 		free(c->c_ssh);
 		fprintf(stderr, "kex_setup: %s\n", ssh_err(r));
@@ -304,7 +326,8 @@ keyprint_one(char *host, struct sshkey *key)
 		fatal("host_hash failed");
 
 	hostport = put_host_port(host, ssh_port);
-	fprintf(stdout, "%s ", hostport);
+	if (!get_cert)
+		fprintf(stdout, "%s ", hostport);
 	sshkey_write(key, stdout);
 	fputs("\n", stdout);
 	free(hostport);
@@ -318,7 +341,7 @@ keyprint(con *c, struct sshkey *key)
 
 	if (key == NULL)
 		return;
-	if (!hash_hosts && ssh_port == SSH_DEFAULT_PORT) {
+	if (get_cert || (!hash_hosts && ssh_port == SSH_DEFAULT_PORT)) {
 		keyprint_one(hosts, key);
 		return;
 	}
@@ -384,6 +407,7 @@ conalloc(char *iname, char *oname, int keytype)
 	if (fdcon[s].c_status)
 		fatal("conalloc: attempt to reuse fdno %d", s);
 
+	debug3("%s: oname %s kt %d", __func__, oname, keytype);
 	fdcon[s].c_fd = s;
 	fdcon[s].c_status = CS_CON;
 	fdcon[s].c_namebase = namebase;
@@ -654,7 +678,7 @@ static void
 usage(void)
 {
 	fprintf(stderr,
-	    "usage: %s [-46Hv] [-f file] [-p port] [-T timeout] [-t type]\n"
+	    "usage: %s [-46Hcv] [-f file] [-p port] [-T timeout] [-t type]\n"
 	    "\t\t   [host | addrlist namelist] ...\n",
 	    __progname);
 	exit(1);
@@ -682,11 +706,14 @@ main(int argc, char **argv)
 	if (argc <= 1)
 		usage();
 
-	while ((opt = getopt(argc, argv, "Hv46p:T:t:f:")) != -1) {
+	while ((opt = getopt(argc, argv, "cHv46p:T:t:f:")) != -1) {
 		switch (opt) {
 		case 'H':
 			hash_hosts = 1;
 			break;
+		case 'c':
+			get_cert = 1;
+			break;
 		case 'p':
 			ssh_port = a2port(optarg);
 			if (ssh_port <= 0) {