Re: Session channel extension to specify home directory?

[Bill Sommerfeld <sommerfeld%sun.com@localhost>]

On Wed, 2005-02-16 at 16:42, Joseph Galbraith wrote:
> We just had a user request us to start a shell session
> for them in an arbitrary directory.
> 
> I was wondering what people would think of the following
> extension (for the session channel only):
> 
> byte      SSH_MSG_CHANNEL_REQUEST
> uint32    recipient channel
> string    "home-directory"
> boolean   want reply
> string    path to use as home directory [UTF-8]

starting the session in an arbitrary directory does not to me imply
setting $HOME.

clearly: 

1) reading authorization information (~/.ssh/authorized_keys or 
~/.*hosts) from a client-specified directory is an incredibly bad idea.
I hope nobody's suggesting that but I run into bad ideas like this often
enough that I feel compelled to point it out...

2) setting $HOME after authentication could be accomplished by the env 
request Niels mentioned.

3) setting the working directory to something other than $HOME could be 
accomplished in most shells by sending over a compound command.  if the
account's shell is not a normal shell, you can't do that -- but in that case 
the account is may also be a captive environment, where setting either of 
the working directory or $HOME might violate the assumption of that 
captive environment.

> What do you think?

Needs a few rounds of "what do you really want to do?" with your users.

							- Bill