Bug#731950: ssh -g has no effect if master socket already open
Package: openssh-client
Version: 1:5.9p1-5
Control: found -1 1:6.4p1-1
From the man page:
-g Allows remote hosts to connect to local forwarded ports.
When working with a control socket, this works fine if -g is included
with the initial connect attempt, for example:
$ cat ~/.ssh/config
Host *
ControlMaster auto
ControlPath ~/.ssh/%r@%h:%p
$ ssh -gTfNL 12345:localhost:12345 host
$ netstat -tln
tcp 0 0 0.0.0.0:12345 0.0.0.0:*
LISTEN -
$ lsof -n
ssh 182446 user 3u IPv4 76397177 0t0
TCP 192.168.0.9:51181->192.168.0.15:ssh (ESTABLISHED)
ssh 182446 user 4u IPv4 76397181 0t0
TCP *:3128 (LISTEN)
ssh 182446 user 5u IPv6 76397182 0t0
TCP *:3128 (LISTEN)
and similarly:
$ ssh -g host
user@host:~$ exit
$ ssh -gTfNL 12345:localhost:12345 host
$ netstat -tln
tcp 0 0 0.0.0.0:12345 0.0.0.0:*
LISTEN -
However, if it isn't then -g is ignored on subsequent attempts to
forward ports:
$ ssh host
user@host:~$ exit
$ ssh -g -L 12345:localhost:12345 host
$ netstat -tln
tcp 0 0 127.0.0.1:12345 0.0.0.0:*
LISTEN -
$ lsof -n
ssh 182399 user 3u IPv4 76390396 0t0
TCP 192.168.0.9:51178->192.168.0.15:ssh (ESTABLISHED)
ssh 182399 user 4u unix 0x0000000000000000 0t0
76390976 /home/user/.ssh/user@host
ssh 182399 user 6u IPv6 76392394 0t0
TCP [::1]:3128 (LISTEN)
ssh 182399 user 7u IPv4 76392395 0t0
TCP 127.0.0.1:3128 (LISTEN)
This doesn't really make sense: ssh should still be capable of binding
to the correct address as requested.
Originally reported:
https://bugs.launchpad.net/ubuntu/+source/openssh/+bug/1259939
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