upstream commit

Make remote channel ID a u_int

Previously we tracked the remote channel IDs in an int, but this is
strictly incorrect: the wire protocol uses uint32 and there is nothing
in-principle stopping a SSH implementation from sending, say, 0xffff0000.

In practice everyone numbers their channels sequentially, so this has
never been a problem.

ok markus@

Upstream-ID: b9f4cd3dc53155b4a5c995c0adba7da760d03e73

1 files changed, 5 insertions, 1 deletions

diff --git a/serverloop.c b/serverloop.c
index 567159410..ae75fc2ec 100644
--- a/serverloop.c
+++ b/serverloop.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: serverloop.c,v 1.197 2017/09/12 06:32:07 djm Exp $ */
+/* $OpenBSD: serverloop.c,v 1.198 2017/09/12 06:35:32 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -619,6 +619,7 @@ server_input_channel_open(int type, u_int32_t seq, struct ssh *ssh)
         if (c != NULL) {
                 debug("server_input_channel_open: confirm %s", ctype);
                 c->remote_id = rchan;
+                c->have_remote_id = 1;
                 c->remote_window = rwindow;
                 c->remote_maxpacket = rmaxpack;
                 if (c->type != SSH_CHANNEL_CONNECTING) {
@@ -844,6 +845,9 @@ server_input_channel_req(int type, u_int32_t seq, struct ssh *ssh)
             c->type == SSH_CHANNEL_OPEN) && strcmp(c->ctype, "session") == 0)
                 success = session_input_channel_req(ssh, c, rtype);
         if (reply && !(c->flags & CHAN_CLOSE_SENT)) {
+                if (!c->have_remote_id)
+                        fatal("%s: channel %d: no remote_id",
+                            __func__, c->self);
                 packet_start(success ?
                     SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
                 packet_put_int(c->remote_id);