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Documentation/git-shell.txt

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+git-shell(1)
+============
+
+NAME
+----
+git-shell - Restricted login shell for Git-only SSH access
+
+
+SYNOPSIS
+--------
+[verse]
+'chsh' -s $(command -v git-shell) <user>
+'git clone' <user>`@localhost:/path/to/repo.git`
+'ssh' <user>`@localhost`
+
+DESCRIPTION
+-----------
+
+This is a login shell for SSH accounts to provide restricted Git access.
+It permits execution only of server-side Git commands implementing the
+pull/push functionality, plus custom commands present in a subdirectory
+named `git-shell-commands` in the user's home directory.
+
+COMMANDS
+--------
+
+'git shell' accepts the following commands after the `-c` option:
+
+'git receive-pack <argument>'::
+'git upload-pack <argument>'::
+'git upload-archive <argument>'::
+	Call the corresponding server-side command to support
+	the client's 'git push', 'git fetch', or 'git archive --remote'
+	request.
+'cvs server'::
+	Imitate a CVS server.  See linkgit:git-cvsserver[1].
+
+If a `~/git-shell-commands` directory is present, 'git shell' will
+also handle other, custom commands by running
+"`git-shell-commands/<command> <arguments>`" from the user's home
+directory.
+
+INTERACTIVE USE
+---------------
+
+By default, the commands above can be executed only with the `-c`
+option; the shell is not interactive.
+
+If a `~/git-shell-commands` directory is present, 'git shell'
+can also be run interactively (with no arguments).  If a `help`
+command is present in the `git-shell-commands` directory, it is
+run to provide the user with an overview of allowed actions.  Then a
+"git> " prompt is presented at which one can enter any of the
+commands from the `git-shell-commands` directory, or `exit` to close
+the connection.
+
+Generally this mode is used as an administrative interface to allow
+users to list repositories they have access to, create, delete, or
+rename repositories, or change repository descriptions and
+permissions.
+
+If a `no-interactive-login` command exists, then it is run and the
+interactive shell is aborted.
+
+EXAMPLES
+--------
+
+To disable interactive logins, displaying a greeting instead:
+
+----------------
+$ chsh -s /usr/bin/git-shell
+$ mkdir $HOME/git-shell-commands
+$ cat >$HOME/git-shell-commands/no-interactive-login <<\EOF
+#!/bin/sh
+printf '%s\n' "Hi $USER! You've successfully authenticated, but I do not"
+printf '%s\n' "provide interactive shell access."
+exit 128
+EOF
+$ chmod +x $HOME/git-shell-commands/no-interactive-login
+----------------
+
+To enable git-cvsserver access (which should generally have the
+`no-interactive-login` example above as a prerequisite, as creating
+the git-shell-commands directory allows interactive logins):
+
+----------------
+$ cat >$HOME/git-shell-commands/cvs <<\EOF
+if ! test $# = 1 && test "$1" = "server"
+then
+	echo >&2 "git-cvsserver only handles \"server\""
+	exit 1
+fi
+exec git cvsserver server
+EOF
+$ chmod +x $HOME/git-shell-commands/cvs
+----------------
+
+SEE ALSO
+--------
+ssh(1),
+linkgit:git-daemon[1],
+contrib/git-shell-commands/README
+
+GIT
+---
+Part of the linkgit:git[1] suite