Problem with reverse tunnel between SSH client 5.5p1 and SSH server > 6.4p1
Hi,
I suffer from some change between OpenSSH 6.4 and 6.5, probably
https://bugzilla.mindrot.org/attachment.cgi?id=2344 (fix for bug
https://bugzilla.mindrot.org/show_bug.cgi?id=2147).
I have an OpenSSH client 1:5.5p1-6+squeeze3 on Debian 6 (Squeeze)
building a reverse tunnel with dynamic port to a Jessie server:
$ /usr/bin/ssh -t -t -R *:0:localhost:443 user@server somecommand
If the server runs OpenSSH up to version 6.4p1-2 ("forwardports" from
snaphot.d.o), everything is fine. With any OpenSSH server from 6.5p1-6
to 7.3p1-3, the tunnel gets established, but no data can be
transmitted over it. On any activity, the client side shows:
WARNING: Server requests forwarding for unknown listen_port 54321
debug1: failure forwarded-tcpip
When the client specifies the port (= no dynamic port):
$ /usr/bin/ssh -t -t -R *:54321:localhost:443 user@server somecommand
everything works fine, independent of the OpenSSH server version.
Reverting part of the change above solves the problem:
--- openssh-7.3p1.orig/channels.c
+++ openssh-7.3p1/channels.c
@@ -1458,7 +1458,7 @@ port_open_helper(Channel *c, char *rtype
} else {
/* listen address, port */
packet_put_cstring(c->path);
- packet_put_int(local_port);
+ packet_put_int(c->listening_port);
}
if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
/* reserved for future owner/mode info */
Can we have this revert in Debian, please?
Or does it have any problems, i.e. what about bug 2147?
TIA & Cheers
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