Re: [PATCH 2/2] shell: pay attention to exit status from 'help' command

> Junio C Hamano wrote:
>> Jonathan Nieder <jrnieder@gmail.com> writes:
>
>>> +To disable interactive logins, displaying a greeting instead:
>>> ++
>>> +----------------
>>> +$ chsh -s /usr/bin/git-shell
>>> +$ mkdir $HOME/git-shell-commands
>>> +$ cat >$HOME/git-shell-commands/help <<\EOF
>>> +#!/bin/sh
>>> +printf '%s\n' "Hi $USER! You've successfully authenticated, but I do not"
>>
>> Where in the sshd to git-shell exec chain is $USER variable set for
>> the user?  Just being curious if this is the simplest but one of the
>> more robust ways to get the user's name.
>
> That's a good question.  environment= in an authorized_keys file is
> obsolete, so USER generally represents the actual logged in user.
>
> That means the main way to base behavior on private key (letting one
> system user represent multiple people) is a gitolite-style command=
> wrapper that checks SSH_ORIGINAL_COMMAND.  In that setup, there is no
> reason to forward simple no-args "are you there?" requests to the
> git-shell, so we can forget about it here.
>
> So by the time we get to git-shell, most likely either
>
>  A) this is a generic system user, with a username like "git", and the
>     above example would insult the client with "Hi git!" or "Hi
>     project-x-git!"
>
> or
>
>  B) each person has a separate account on the system, perhaps to help
>     the admin to set filesystem permissions based on users and groups,
>     and the above would address the user by her normal name.