diff options
Diffstat (limited to 'ansible/docker/run_chroot.sh')
| -rwxr-xr-x | ansible/docker/run_chroot.sh | 418 |
1 files changed, 156 insertions, 262 deletions
diff --git a/ansible/docker/run_chroot.sh b/ansible/docker/run_chroot.sh index 3359fdcd..268143ed 100755 --- a/ansible/docker/run_chroot.sh +++ b/ansible/docker/run_chroot.sh @@ -22,7 +22,6 @@ set -e CMD=$(basename "$0") -UMOUNT_TIMEOUT=120 # 2mins # @@ -106,31 +105,18 @@ EXAMPLE: " } -# arg: <directory> -is_mounted() -{ - mountpoint=$(echo "$1" | sed 's#//*#/#g') - - LANG=C mount | grep -q "^[^[:space:]]\+[[:space:]]\+on[[:space:]]\+${mountpoint}[[:space:]]\+type[[:space:]]\+" -} - # layers are right to left! First is on the right, top/last is on the left do_overlay_mount() { - if [ -d "$overlay" ] && is_mounted "$overlay" ; then - echo ERROR: "The overlay directory is already mounted: $overlay" >&2 - echo ERROR: "Fix the issue - cannot proceed" >&2 - exit 1 - fi - # prepare dirs - rm -rf "$overlay" "$upperdir" "$workdir" +mkdir -p $ovtempdir +mount -t tmpfs -o mode=0755 tmpfs $ovtempdir mkdir -p "$overlay" mkdir -p "$upperdir" mkdir -p "$workdir" # finally overlay mount - if ! mount -t overlay --make-rprivate \ + if ! mount -t overlay \ -o lowerdir="$lowerdir",upperdir="$upperdir",workdir="$workdir" \ overlay "$overlay" ; then @@ -147,40 +133,16 @@ do_overlay_mount() return 0 } -cleanup() -{ - case "$OVERLAY_MOUNT" in - yes) - echo INFO: "Umounting overlay..." >&2 - if ! umount_retry "$CHROOT_DIR" ; then - echo ERROR: "Cannot umount chroot: $CHROOT_DIR" >&2 - return 1 - fi - - ;; - no) - echo INFO: "No overlay to umount" >&2 - ;; - esac - - if ! is_mounted "$overlay" ; then - echo INFO: "Deleting of temp directories..." >&2 - rm -rf "$overlay" "$upperdir" "$workdir" - else - echo ERROR: "Overlay is still mounted: $CHROOT_DIR" >&2 - echo ERROR: "Cannot delete: $overlay" >&2 - echo ERROR: "Cannot delete: $upperdir" >&2 - echo ERROR: "Cannot delete: $workdir" >&2 - return 1 - fi -} - check_external_mounts() { - echo "$EXTERNAL_MOUNTS" | sed '/^[[:space:]]*$/d' | while read -r mountexpr ; do + echo "$EXTERNAL_MOUNTS" | while read -r mountexpr ; do + #Skip empty lines, done with if for readability. + if [ -z $mountexpr ]; then + continue + fi mount_type=$(echo "$mountexpr" | awk 'BEGIN{FS=":"}{print $1;}') external=$(echo "$mountexpr" | awk 'BEGIN{FS=":"}{print $2;}') - internal=$(echo "$mountexpr" | awk 'BEGIN{FS=":"}{print $3;}' | sed -e 's#^/*##' -e 's#//*#/#g') + internal=$(echo "$mountexpr" | awk 'BEGIN{FS=":"}{print $3;}') case "$mount_type" in ro|rw) @@ -203,16 +165,13 @@ check_external_mounts() do_external_mounts() { echo INFO: "Bind mounting of external mounts..." >&2 - echo "$EXTERNAL_MOUNTS" | sed '/^[[:space:]]*$/d' | while read -r mountexpr ; do + echo "$EXTERNAL_MOUNTS" | while read -r mountexpr ; do + if [ -z $mountexpr ]; then + continue + fi mount_type=$(echo "$mountexpr" | awk 'BEGIN{FS=":"}{print $1;}') external=$(echo "$mountexpr" | awk 'BEGIN{FS=":"}{print $2;}') - internal=$(echo "$mountexpr" | awk 'BEGIN{FS=":"}{print $3;}' | sed -e 's#^/*##' -e 's#//*#/#g') - - if is_mounted "${CHROOT_DIR}/${internal}" ; then - echo ERROR: "Mountpoint is already mounted: ${CHROOT_DIR}/${internal}" >&2 - echo ERROR: "Fix the issue - cannot proceed" >&2 - exit 1 - fi + internal=$(echo "$mountexpr" | awk 'BEGIN{FS=":"}{print $3;}') # trying to follow the behaviour of docker if ! [ -e "$external" ] || [ -d "$external" ] ; then @@ -242,7 +201,9 @@ do_external_mounts() exit 1 fi - if ! mount --make-rprivate -o bind,${mount_type} "$external" "${CHROOT_DIR}/${internal}" ; then +#Note, this double mounting is needed to support older util-linux. + if ! mount -o bind "${external}" "${CHROOT_DIR}/${internal}" || + ! mount -o remount,bind,${mount_type} "${CHROOT_DIR}/${internal}" ; then echo ERROR: "Failed to mount: ${external} -> ${internal}" >&2 exit 1 else @@ -251,231 +212,164 @@ do_external_mounts() done } -# arg: <mountpoint> -umount_retry() -{ - mountpoint=$(echo "$1" | sed 's#//*#/#g') - timeout=${UMOUNT_TIMEOUT} - - umount "$mountpoint" 2>/dev/null - while is_mounted "$mountpoint" && [ $timeout -gt 0 ] ; do - umount "$mountpoint" 2>/dev/null - sleep 1 - timeout=$(( timeout - 1 )) - done - - if ! is_mounted "$mountpoint" ; then - return 0 - fi - - return 1 -} - -undo_external_mounts() -{ - echo INFO: "Umount external mount points..." >&2 - echo "$EXTERNAL_MOUNTS" | tac | sed '/^[[:space:]]*$/d' | while read -r mountexpr ; do - mount_type=$(echo "$mountexpr" | awk 'BEGIN{FS=":"}{print $1;}') - external=$(echo "$mountexpr" | awk 'BEGIN{FS=":"}{print $2;}') - internal=$(echo "$mountexpr" | awk 'BEGIN{FS=":"}{print $3;}' | sed -e 's#^/*##' -e 's#//*#/#g') - if umount_retry "${CHROOT_DIR}/${internal}" ; then - echo INFO: "Unmounted: ${CHROOT_DIR}/${internal}" >&2 - else - echo ERROR: "Failed to umount: ${CHROOT_DIR}/${internal}" >&2 - fi - done -} - -install_wrapper() -{ - cat > "$CHROOT_DIR"/usr/local/bin/fakeshell.sh <<EOF -#!/bin/sh - -PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin -export PATH - -gid_tty=\$(getent group | sed -n '/^tty:/p' | cut -d: -f 3) - -mount -t proc proc /proc -mount -t sysfs none /sys -mount -t tmpfs none /dev - -mkdir -p /dev/shm -mkdir -p /dev/pts -mount -t devpts -o gid=\${gid_tty},mode=620 none /dev/pts - -[ -e /dev/full ] || mknod -m 666 /dev/full c 1 7 -[ -e /dev/ptmx ] || mknod -m 666 /dev/ptmx c 5 2 -[ -e /dev/random ] || mknod -m 644 /dev/random c 1 8 -[ -e /dev/urandom ] || mknod -m 644 /dev/urandom c 1 9 -[ -e /dev/zero ] || mknod -m 666 /dev/zero c 1 5 -[ -e /dev/tty ] || mknod -m 666 /dev/tty c 5 0 -[ -e /dev/console ] || mknod -m 622 /dev/console c 5 1 -[ -e /dev/null ] || mknod -m 666 /dev/null c 1 3 - -chown root:tty /dev/console -chown root:tty /dev/ptmx -chown root:tty /dev/tty - -mkdir -p "\$1" || exit 1 -cd "\$1" || exit 1 -shift - -exec "\$@" - -EOF - chmod +x "$CHROOT_DIR"/usr/local/bin/fakeshell.sh -} - -on_exit() -{ - set +e - echo - - if [ -n "$OVERLAY_MOUNT" ] ; then - undo_external_mounts - fi - cleanup -} # -# parse arguments +# parse arguments out of namespace. # -state=nil -action=nil -EXTERNAL_MOUNTS='' -CHROOT_WORKDIR='' -CHROOT_METADIR='' -CHROOT_DIR='' -COMMAND='' -while [ -n "$1" ] ; do - case "$state" in - nil) - case "$1" in - ''|-h|--help|help) - help - exit 0 - ;; - --mount) - EXTERNAL_MOUNTS=$(printf "%s\n%s\n" "$EXTERNAL_MOUNTS" "${2}") - state=next - ;; - --workdir) - if [ -z "$CHROOT_WORKDIR" ] ; then - CHROOT_WORKDIR="$2" +if [ -z $IN_NAMESPACE ]; then + export state=nil + export action=nil + export EXTERNAL_MOUNTS='' + export CHROOT_WORKDIR='' + export CHROOT_METADIR='' + export CHROOT_DIR='' + export COMMAND='' + while [ -n "$1" ] ; do + case "$state" in + nil) + case "$1" in + ''|-h|--help|help) + help + exit 0 + ;; + --mount) + EXTERNAL_MOUNTS=$(printf "%s\n%s" "$EXTERNAL_MOUNTS" "${2}") state=next - else - echo ERROR: "Multiple working directory argument" >&2 + ;; + --workdir) + if [ -z "$CHROOT_WORKDIR" ] ; then + CHROOT_WORKDIR="$2" + state=next + else + echo ERROR: "Multiple working directory argument" >&2 + help >&2 + exit 1 + fi + ;; + execute) + action=execute + state=execute + ;; + *) + echo ERROR: "Bad usage" >&2 help >&2 exit 1 - fi - ;; - execute) - action=execute - state=execute - ;; - *) - echo ERROR: "Bad usage" >&2 - help >&2 - exit 1 - ;; - esac - ;; - next) - state=nil - ;; - execute) - CHROOT_METADIR="$1" - shift - break - ;; - esac - shift -done - - -case "$action" in - ''|nil) + ;; + esac + ;; + next) + state=nil + ;; + execute) + CHROOT_METADIR="$1" + shift + break + ;; + esac + shift + done + + + if [ $action = "nil" ]; then echo ERROR: "Nothing to do - missing command" >&2 help >&2 exit 1 - ;; - execute) - # firstly do sanity checking ... - - if [ -z "$CHROOT_METADIR" ] ; then - echo ERROR: "Missing argument" >&2 - help >&2 - exit 1 - fi - - # making sure that CHROOT_METADIR is absolute path - CHROOT_METADIR=$(readlink -f "$CHROOT_METADIR") - - if ! [ -d "$CHROOT_METADIR"/chroot ] ; then - echo ERROR: "Filepath does not exist: ${CHROOT_METADIR}/chroot" >&2 - exit 1 - fi - - # check external mounts if there are any - check_external_mounts - - # check workdir - if [ -n "$CHROOT_WORKDIR" ] ; then - CHROOT_WORKDIR=$(echo "$CHROOT_WORKDIR" | sed -e 's#^/*##' -e 's#//*#/#g') - fi - - # we must be root - if [ "$(id -u)" -ne 0 ] ; then - echo ERROR: "Need to be root and you are not: $(id -nu)" >&2 - exit 1 - fi + fi - if ! which unshare >/dev/null 2>/dev/null ; then - echo ERROR: "'unshare' system command is missing - ABORT" >&2 - echo INFO: "Try to install 'util-linux' package" >&2 - exit 1 - fi + # do sanity checking ... - # ... sanity checking done + if [ -z "$CHROOT_METADIR" ] ; then + echo ERROR: "Missing argument" >&2 + help >&2 + exit 1 + fi - # setup paths - lowerdir="$CHROOT_METADIR"/chroot - upperdir="$CHROOT_METADIR"/.overlay - workdir="$CHROOT_METADIR"/.workdir - overlay="$CHROOT_METADIR"/.merged + # making sure that CHROOT_METADIR is absolute path + CHROOT_METADIR=$(readlink -f "$CHROOT_METADIR") - # set trap - trap on_exit QUIT TERM EXIT + if ! [ -d "$CHROOT_METADIR"/chroot ] ; then + echo ERROR: "Filepath does not exist: ${CHROOT_METADIR}/chroot" >&2 + exit 1 + fi - # mount overlay - OVERLAY_MOUNT='' - if do_overlay_mount ; then - # overlay chroot - OVERLAY_MOUNT=yes - else - # non overlay mount - OVERLAY_MOUNT=no - fi + # check external mounts if there are any + check_external_mounts - # do the user-specific mounts - do_external_mounts + # we must be root + if [ "$(id -u)" -ne 0 ] ; then + echo ERROR: "Need to be root and you are not: $(id -nu)" >&2 + exit 1 + fi - # I need this wrapper to do some setup inside the chroot... - install_wrapper + if ! which unshare >/dev/null 2>/dev/null ; then + echo ERROR: "'unshare' system command is missing - ABORT" >&2 + echo INFO: "Try to install 'util-linux' package" >&2 + exit 1 + fi - # execute chroot - if [ -n "$1" ] ; then - : - else - set -- /bin/sh -l - fi - unshare -mfpi --propagation private \ - chroot "$CHROOT_DIR" /usr/local/bin/fakeshell.sh "${CHROOT_WORKDIR:-/}" "$@" - ;; -esac + # ... sanity checking done + + #Reexec ourselves in new pid and mount namespace (isolate!). + #Note: newly executed shell will be pid1 in a new namespace. Killing it will kill + #every other process in the whole process tree with sigkill. That will in turn + #destroy namespaces and undo all mounts done previously. + IN_NAMESPACE=1 exec unshare -mpf "$0" "$@" +fi + +#We are namespaced. +# setup paths +lowerdir="$CHROOT_METADIR"/chroot +ovtempdir="$CHROOT_METADIR"/tmp +upperdir="$ovtempdir"/.overlay +workdir="$ovtempdir"/.workdir +overlay="$CHROOT_METADIR"/.merged + +#In case we are using a realy old unshare, make the whole tree into private mounts manually. +mount --make-rprivate / +#New mounts are private always from now on. + +do_overlay_mount + +# do the user-specific mounts +do_external_mounts + +#And setup api filesystems. +mount -t proc proc "${CHROOT_DIR}/proc" +mount -t sysfs none "${CHROOT_DIR}/sys" +mount -t tmpfs none "${CHROOT_DIR}/dev" + +mkdir -p "${CHROOT_DIR}/dev/shm" +mkdir -p "${CHROOT_DIR}/dev/pts" +mount -t devpts none "${CHROOT_DIR}/dev/pts" + +mknod -m 666 "${CHROOT_DIR}/dev/full" c 1 7 +mknod -m 666 "${CHROOT_DIR}/dev/ptmx" c 5 2 +mknod -m 644 "${CHROOT_DIR}/dev/random" c 1 8 +mknod -m 644 "${CHROOT_DIR}/dev/urandom" c 1 9 +mknod -m 666 "${CHROOT_DIR}/dev/zero" c 1 5 +mknod -m 666 "${CHROOT_DIR}/dev/tty" c 5 0 +mknod -m 622 "${CHROOT_DIR}/dev/console" c 5 1 +mknod -m 666 "${CHROOT_DIR}/dev/null" c 1 3 +ln -s /proc/self/fd/0 "$CHROOT_DIR/dev/stdin" +ln -s /proc/self/fd/1 "$CHROOT_DIR/dev/stdout" +ln -s /proc/self/fd/2 "$CHROOT_DIR/dev/stderr" + +# execute chroot +if [ -z "$1" ] ; then + set -- /bin/sh -l +fi + +#The redirection is to save our stdin, because we use it to pipe commands and we +#may want interactivity. +exec chroot "${CHROOT_DIR}" /bin/sh /dev/stdin "${CHROOT_WORKDIR:-/}" "$@" 3<&0 << "EOF" +mkdir -p $1 +cd $1 +shift +#I intend to reset stdin back *and* close the copy. +exec "$@" <&3 3<&- +EOF exit 0 |