upstream commit

UpdateHostKeys fixes:

I accidentally changed the format of the hostkeys@openssh.com messages
last week without changing the extension name, and this has been causing
connection failures for people who are running -current. First reported
by sthen@

s/hostkeys@openssh.com/hostkeys-00@openssh.com/
Change the name of the proof message too, and reorder it a little.

Also, UpdateHostKeys=ask is incompatible with ControlPersist (no TTY
available to read the response) so disable UpdateHostKeys if it is in
ask mode and ControlPersist is active (and document this)

1 files changed, 13 insertions, 10 deletions

diff --git a/clientloop.c b/clientloop.c
index a19d9d06f..ca3a4595b 100644
--- a/clientloop.c
+++ b/clientloop.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: clientloop.c,v 1.269 2015/02/16 22:13:32 djm Exp $ */
+/* $OpenBSD: clientloop.c,v 1.270 2015/02/20 22:17:21 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -2265,10 +2265,10 @@ client_global_hostkeys_private_confirm(int type, u_int32_t seq, void *_ctx)
                         continue;
                 /* Prepare data to be signed: session ID, unique string, key */
                 sshbuf_reset(signdata);
-                if ((r = sshbuf_put_string(signdata, ssh->kex->session_id,
+                if ( (r = sshbuf_put_cstring(signdata,
+                    "hostkeys-prove-00@openssh.com")) != 0 ||
+                    (r = sshbuf_put_string(signdata, ssh->kex->session_id,
                     ssh->kex->session_id_len)) != 0 ||
-                    (r = sshbuf_put_cstring(signdata,
-                    "hostkeys-prove@openssh.com")) != 0 ||
                     (r = sshkey_puts(ctx->keys[i], signdata)) != 0)
                         fatal("%s: failed to prepare signature: %s",
                             __func__, ssh_err(r));
@@ -2300,7 +2300,7 @@ client_global_hostkeys_private_confirm(int type, u_int32_t seq, void *_ctx)
 }
 
 /*
- * Handle hostkeys@openssh.com global request to inform the client of all
+ * Handle hostkeys-00@openssh.com global request to inform the client of all
  * the server's hostkeys. The keys are checked against the user's
  * HostkeyAlgorithms preference before they are accepted.
  */
@@ -2335,8 +2335,10 @@ client_input_hostkeys(void)
                             __func__, ssh_err(r));
                         goto out;
                 }
-                if ((r = sshkey_from_blob(blob, len, &key)) != 0)
-                        fatal("%s: parse key: %s", __func__, ssh_err(r));
+                if ((r = sshkey_from_blob(blob, len, &key)) != 0) {
+                        error("%s: parse key: %s", __func__, ssh_err(r));
+                        goto out;
+                }
                 fp = sshkey_fingerprint(key, options.fingerprint_hash,
                     SSH_FP_DEFAULT);
                 debug3("%s: received %s key %s", __func__,
@@ -2376,9 +2378,10 @@ client_input_hostkeys(void)
         }
 
         if (ctx->nkeys == 0) {
-                error("%s: server sent no hostkeys", __func__);
+                debug("%s: server sent no hostkeys", __func__);
                 goto out;
         }
+
         if ((ctx->keys_seen = calloc(ctx->nkeys,
             sizeof(*ctx->keys_seen))) == NULL)
                 fatal("%s: calloc failed", __func__);
@@ -2418,7 +2421,7 @@ client_input_hostkeys(void)
                     __func__, ctx->nnew);
                 if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
                     (r = sshpkt_put_cstring(ssh,
-                    "hostkeys-prove@openssh.com")) != 0 ||
+                    "hostkeys-prove-00@openssh.com")) != 0 ||
                     (r = sshpkt_put_u8(ssh, 1)) != 0) /* bool: want reply */
                         fatal("%s: cannot prepare packet: %s",
                             __func__, ssh_err(r));
@@ -2465,7 +2468,7 @@ client_input_global_request(int type, u_int32_t seq, void *ctxt)
         want_reply = packet_get_char();
         debug("client_input_global_request: rtype %s want_reply %d",
             rtype, want_reply);
-        if (strcmp(rtype, "hostkeys@openssh.com") == 0)
+        if (strcmp(rtype, "hostkeys-00@openssh.com") == 0)
                 success = client_input_hostkeys();
         if (want_reply) {
                 packet_start(success ?