upstream: move client/server SSH-* banners to buffers under

ssh->kex and factor out the banner exchange. This eliminates some common code
from the client and server.

Also be more strict about handling \r characters - these should only
be accepted immediately before \n (pointed out by Jann Horn).

Inspired by a patch from Markus Schmidt.
(lots of) feedback and ok markus@

OpenBSD-Commit-ID: 1cc7885487a6754f63641d7d3279b0941890275b

1 files changed, 3 insertions, 3 deletions

diff --git a/kexgexc.c b/kexgexc.c
index 0d07f73c7..f2be35ab2 100644
--- a/kexgexc.c
+++ b/kexgexc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexgexc.c,v 1.27 2018/02/07 02:06:51 jsing Exp $ */
+/* $OpenBSD: kexgexc.c,v 1.29 2018/12/27 03:25:25 djm Exp $ */
 /*
  * Copyright (c) 2000 Niels Provos.  All rights reserved.
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
@@ -222,8 +222,8 @@ input_kex_dh_gex_reply(int type, u_int32_t seq, struct ssh *ssh)
         hashlen = sizeof(hash);
         if ((r = kexgex_hash(
             kex->hash_alg,
-            kex->client_version_string,
-            kex->server_version_string,
+            kex->client_version,
+            kex->server_version,
             sshbuf_ptr(kex->my), sshbuf_len(kex->my),
             sshbuf_ptr(kex->peer), sshbuf_len(kex->peer),
             server_host_key_blob, sbloblen,