Bug#369401: openssh-client: SenvEnv misses possibility to reset/override/disable previous settings

[Andreas Beckmann <debian@abeckmann.de>]

Package: openssh-client
Version: 1:4.3p2-2
Severity: wishlist

Hi,

the SendEnv config option is an 'append-only' option making it
impossible to overwrite settings from /etc/ssh/ssh_config (the default
there is 'SendEnv LANG LC_*') in .ssh/config
This may be needed for 'broken servers' that don't have the locales
available that are used on the client, but still run a sshd with
'AcceptEnv LANG LC_*' resulting in tons of error messages during login.

I could imagine a few possibilities to enhance SendEnv:

# SendEnv without any arguments clears the current list
SendEnv

# SendEnv with special argument '!' clears the current list
SendEnv !

# variables prefixed with an '!' won't be exported to the server
# even is they are in the SenvEnv list
# (Each SendEnv option appends to the right side of the list
# the list is checked from left to right and the rightmost match
# determines the fate of a variable.)
SendEnv !LC_* LC_FOO
# would override the LC_* setting (but not the LANG setting) from
# /etc/ssh/ssh_config, as a result LANG and LC_FOO would be exported to
# the server

Since there is no client specific sshd_config a reset/clear argument
for AcceptEnv would not be useful, but the '!' prefix could be:

# this machine only speaks POSIX
AcceptEnv LANG LC_* !LC_MESSAGES


Andreas

-- System Information:
Debian Release: testing/unstable
  APT prefers testing
  APT policy: (900, 'testing'), (900, 'stable'), (600, 'unstable')
Architecture: i386 (i686)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.16-1-k7
Locale: LANG=C, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)

Versions of packages openssh-client depends on:
ii  adduser       3.87                       Add and remove users and groups
ii  debconf [debc 1.5.1                      Debian configuration management sy
ii  dpkg          1.13.19                    package maintenance system for Deb
ii  libc6         2.3.6-7                    GNU C Library: Shared libraries
ii  libcomerr2    1.38+1.39-WIP-2005.12.31-1 common error description library
ii  libedit2      2.9.cvs.20050518-2.2       BSD editline and history libraries
ii  libkrb53      1.4.3-7                    MIT Kerberos runtime libraries
ii  libncurses5   5.5-2                      Shared libraries for terminal hand
ii  libselinux1   1.30-1                     SELinux shared libraries
ii  libssl0.9.8   0.9.8b-2                   SSL shared libraries
ii  zlib1g        1:1.2.3-11                 compression library - runtime

openssh-client recommends no packages.

-- no debconf information