[Bug 302791] [NEW] ssh not setting XAUTHORITY, XDG_SESSION_COOKIE

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Description:	Ubuntu 8.04.1
Release:	8.04

When logging in to a machine through ssh (without -X or -Y), XAUTHORITY
is not set; and when logging in non-interactively, XDG_SESSION_COOKIE is
not set.  This prevents programs started over an ssh session to connect
to the X server of the machine on which it's running.

I use synergy to control my work desktop from my laptop (and so I have
more screen real estate).  I wrote the following script to automatically
run the synergy server and client when I come in to work in the morning:

#!/bin/bash
killall synergys
ssh gdunlap at elijah "killall synergyc"
synergys
ssh -R 24800:localhost:24800 gdunlap at elijah "synergyc -f --name elijah localhost"
ssh gdunlap at elijah "killall synergyc"
killall synergys

It worked until I upgraded this morning, at which point it gave the
following error:

DEBUG: CXWindowsScreen.cpp,840: XOpenDisplay(":0.0")
No protocol specified
WARNING: synergyc.cpp,337: cannot open secondary screen: unable to open screen

Digging a little deeper, I found that synergyc was trying to use
~/.Xauthority instead of /tmp/.gdm[...] as it should have, because
XAUTHORITY was not being set when logging in over ssh.

Furthermore, I discovered that if I logged in using an interactive shell
and set XAUTHORITY manually, then synergyc worked; but if I set
XAUTHORITY script-wise in a non-interactive shell, it still didn't work.
Further investigation revealed that in the interactive shell,
XDG_SESSION_COOKIE is being set, but in a non-interactive shell, it's
not being set.  If logged in interactively and unset XDG_SESSION_COOKIE,
it failed the same way as if I logged in non-interactively.

I'm not sure what the behavior was before, because things "just worked".
:-)  When I first came in this morning, the script worked, but not after
I did a apt-get update.  I believe the packages updated were libc,
fglrx-control, and some linux modles.  libc is the most likely-looking
candidate.

** Affects: openssh (Ubuntu)
     Importance: Undecided
         Status: New

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ssh not setting XAUTHORITY, XDG_SESSION_COOKIE
https://bugs.launchpad.net/bugs/302791
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