#!/bin/bash
# Copyright © 2010  Sascha Silbe <sascha-pgp@silbe.org>
#
# schroot is free software: you can redistribute it and/or modify it
# under the terms of the GNU General Public License version 3
# as published by the Free Software Foundation.
#
# schroot is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see
# <http://www.gnu.org/licenses/>.
#
#####################################################################
# 10mount-ssh: "Forward" ssh-agent to chroot.
# Performs a bind-mount of the ssh-agent socket directory. Clean-up
# happens at session end in setup.d/10mount.
#####################################################################

set -e

. "$SETUP_DATA_DIR/common-data"
. "$SETUP_DATA_DIR/common-functions"
. "$SETUP_DATA_DIR/common-config"

ACTION="$1"

SYMLINK_PATH="${CHROOT_PATH}/tmp/ssh-auth-sock.${SESSION_ID}"

if [ "$ACTION" = "setup-stop" -o "$ACTION" = "setup-recover" ] \
    && [ -h "${SYMLINK_PATH}" ]; then
    SOCK_PATH="${CHROOT_PATH}/$(readlink "${SYMLINK_PATH}")"
    info "Unmounting ${SOCK_PATH}"
    umount -f "${SOCK_PATH}"
    rm -f "${SYMLINK_PATH}"
fi

if [ "$ACTION" = "setup-start" -o "$ACTION" = "setup-recover" ] ; then
    # Extract SSH_AUTH_SOCK from environment of schroot process ($PID)
    SSH_AUTH_SOCK="$(tr '\0' '\n' < /proc/"$PID"/environ | grep ^SSH_AUTH_SOCK | head -n 1 |sed -e 's/^SSH_AUTH_SOCK=//')"

    if [ -z "${SSH_AUTH_SOCK:-}" ] \
	|| [ -e "${CHROOT_PATH}/${SSH_AUTH_SOCK}" ] ; then
        exit 0
    fi

    info "Mounting ${CHROOT_PATH}/${SSH_AUTH_SOCK}"
    SOCK_DIR="$(dirname "${SSH_AUTH_SOCK}")"
    mkdir -p "${CHROOT_PATH}/${SOCK_DIR}"
    touch "${CHROOT_PATH}/${SSH_AUTH_SOCK}"
    mount -o bind "${SSH_AUTH_SOCK}" "${CHROOT_PATH}/${SSH_AUTH_SOCK}"
    mkdir -p "$(dirname "${SYMLINK_PATH}")"
    rm -f "${SYMLINK_PATH}"
    ln -s "${SSH_AUTH_SOCK}" "${SYMLINK_PATH}"
fi