liberte/enter

#!/bin/sh -e

sinfo() {
    echo ${BASH:+-e} "\033[1;33;41m$@\033[0m"
}


# Must have root directory as an argument
if [ -z "$1" ]; then
    echo "$0 <livecd root> [copy] [-c 'shell command']"
    exit 1
fi


# Launch in a separate mount namespace
if [ unshare != "$1" ]; then
    exec unshare -m -- "$0" unshare "$@"
else
    shift
fi


# Variables
SRC=`dirname $0`/src
RSYNC="rsync -rlptOHS"

version=`cat ${SRC}/../conf/version`
environment="LVERSION=${version} LOGNAME=root USER=root HOME=/root HOSTNAME=liberte"
for env in LANG TERM RSYNC_PROXY http_proxy https_proxy ftp_proxy no_proxy; do
    if printenv ${env} 1>/dev/null; then
        environment="${environment} ${env}=`printenv ${env}`"
    fi
done


# Tweak target directory if alternative is given,
# otherwise, synchronize configuration
if [ "$2" = copy ]; then
    PHASE=$2
    LIVECD=$1/${PHASE}
    shift 2
else
    PHASE=src
    LIVECD=$1/${PHASE}
    shift

    # NOTE: non-pruned files: /, /etc/portage/gnupg, /etc/privoxy, /var/lib/portage
    #                         /home/anon/persist/security/pgp/*.{gpg,crt}

    # Specify permissions completely, to be independent from ${SRC}/* chmods
    sinfo "Copying configuration files:"
    ${RSYNC} --chmod=u=rwX,go=rX -i        \
          --exclude=/root/                 \
          --exclude=/home/anon/            \
          --exclude=/home/nofw/            \
          --exclude=/var/lib/portage/      \
          --exclude=/usr/local/portage/    \
          --exclude=/etc/sudoers           \
          --exclude=/etc/sysctl.conf       \
          --exclude=/etc/polkit-1          \
          --exclude=/etc/portage/gnupg/ -C ${SRC}/ ${LIVECD}

    ${RSYNC} --chmod=u=rwX,go=rX -i --delete-excluded \
        -C --exclude=.gitignore                          ${SRC}/root              ${LIVECD}
    ${RSYNC} --chmod=u=rwX,go=   -i                   -C ${SRC}/etc/portage/gnupg ${LIVECD}/etc/portage
    ${RSYNC} --chmod=u=rwX,go=rX,Dg+s -i              -C ${SRC}/var/lib/portage   ${LIVECD}/var/lib
    ${RSYNC} --chmod=u=rwX,go=rX -i --delete --exclude=/portage/distfiles -C ${SRC}/usr/local/portage ${LIVECD}/usr/local

    if [ -e ${LIVECD}/var/log/privoxy ]; then
        chown -hR --from=`stat -c %u:%g ${LIVECD}/var/log/privoxy` 0:0 ${LIVECD}/etc/privoxy
    fi

    ${RSYNC} --chmod=ug=r,o=     -i ${SRC}/etc/sudoers           ${LIVECD}/etc
    ${RSYNC} --chmod=u=rw,g=r,o= -i ${SRC}/etc/sysctl.conf       ${LIVECD}/etc

    if [ -e ${LIVECD}/etc/polkit-1/rules.d ]; then
        ${RSYNC} --chmod=u=rwX,go=rX -i -C \
            ${SRC}/etc/polkit-1/rules.d/* ${LIVECD}/etc/polkit-1/rules.d
    fi

    mkdir -p -m 755 ${LIVECD}/usr/local/addons
    ${RSYNC} --chmod=u=rwX,go=rX -i --delete-excluded -C ${SRC}/../conf/certs ${LIVECD}/usr/local/addons

    # rwX------
    ${RSYNC} --chmod=u=rwX,go=   -i --delete \
          --exclude=/anon/persist/security/pgp/\*.gpg --exclude=/anon/persist/security/pgp/\*.crt \
          --exclude=/anon/persist/cables/queue        --exclude=/anon/persist/cables/rqueue       \
          --exclude=/anon/persist/mail/inbox          -C ${SRC}/home/anon ${LIVECD}/home
    ${RSYNC} --chmod=ug=rwX,o=,Do+t -i --delete-excluded \
        -C ${SRC}/home/anon/persist/cables/queue ${SRC}/home/anon/persist/cables/rqueue \
        ${LIVECD}/home/anon/persist/cables
    ${RSYNC} --chmod=ug=rwX,o=,Do+t -i --delete-excluded \
        -C ${SRC}/home/anon/persist/mail/inbox   ${LIVECD}/home/anon/persist/mail
    chown -hR --from=0:0 2101:9000 ${LIVECD}/home/anon

    ${RSYNC} --chmod=u=rwX,go=   -i --delete-excluded -C ${SRC}/home/nofw ${LIVECD}/home
    chown -hR --from=0:0 2102:9001 ${LIVECD}/home/nofw

    if [ -e /etc/resolv.conf ]; then
        ${RSYNC} -L --chmod=u=rw,go=r -i /etc/resolv.conf ${LIVECD}/etc
    fi
fi
environment="${environment} PHASE=${PHASE}"

setarch=`which setarch`
chroot=`which chroot`
tty=`tty`
mounted=


sinfo "Mounting system directories"

[ "${tty#/dev/pts/}" = "${tty}" ] || tty=
[ -L ${LIVECD}/dev/fd ] || ln -sfT /proc/self/fd ${LIVECD}/dev/fd
loop=`losetup -f`

for mp in /proc /dev/null /dev/random /dev/urandom /dev/tty /dev/ptmx /dev/pts /dev/shm ${loop} ${tty}; do
    if [ ${mp#/dev/loop} = ${mp} ]; then
        lmp=${LIVECD}${mp}
    else
        lmp=${LIVECD}/dev/loop
    fi
    if [ ! -e ${lmp} ]; then
        if   [ -d ${mp} ]; then
            mkdir -m 755 ${lmp}
        elif [ -e ${mp} ]; then
            touch ${lmp}
        fi
    fi
    mount -B ${mp} ${lmp}
    mounted="${lmp} ${mounted}"
done
mount -rB -o remount ${LIVECD}/proc

if   [ ${PHASE} = src ]; then
    mkdir -p -m 755 ${LIVECD}/../copy ${LIVECD}/../dist
    mount -B ${LIVECD}/../copy ${LIVECD}/mnt/live
    mount -B ${LIVECD}/../dist ${LIVECD}/mnt/boot
elif [ ${PHASE} = copy  -a  -d ${LIVECD}/usr/portage ]; then
    mount -B ${LIVECD}/../src/usr/portage ${LIVECD}/usr/portage
    mount -rB -o remount ${LIVECD}/usr/portage
fi


sinfo "Environment:"
echo "${environment}" | tr ' ' '\n' | sed 's/^/    /'


sinfo "Launching chrooted shell in ${LIVECD}"
set +e
env -i ${environment} "${setarch}" i686 "${chroot}" ${LIVECD} /bin/bash -l "$@"
retval=$?
if [ ${retval} != 0 ]; then
    sinfo "Failed."
fi


# Unnecessary with unshare -m, but stale processes might hold the mounts
sinfo "Unmounting system directories"

if   [ ${PHASE} = src ]; then
    umount ${LIVECD}/mnt/live ${LIVECD}/mnt/boot
elif [ ${PHASE} = copy  -a  -d ${LIVECD}/usr/portage ]; then
    umount ${LIVECD}/usr/portage
fi

umount -l ${mounted}

# Condition is false for empty and for block-device ${tty} (i.e., unmount failed)
[ ! -f ${LIVECD}${tty} ] || rm ${LIVECD}${tty}


exit ${retval}