# is an overlay of the subhost's root and an OS root. The service
# subhost is defined by a configuration file named on teh command line
+OVERLAYDIR="$(realpath $(dirname $0))"
+
[ $(id -u) = 0 ] || exec sudo $0 $@
. $(dirname $(realpath $0))/functions $*
+
CONFIG="$1"
[ -r "$CONFIG" ] || die "Missing configuration $CONFIG"
+
config NAME $(basename $1 .${1##*.})
config LOG /tmp/oly-$NAME.log
#
# Create the network namespace for the subhost, then trigger
# detached re-run with unshared mount namespace
- [ -r /run/netns/$NAME ] || ip netns add $NAME
+ [ -r /run/netns/$NAME ] || {
+ ip netns add $NAME
+ ip netns exec $NAME ip link set lo up
+ }
exec env UNSHARED=yes unshare -m $0 $@ > $LOG 2>&1 &
echo "Logging to $LOG" >&2
exit 0
config BASE
BASE="$(cd $(dirname $CONFIG); realpath $BASE)"
+[ -z "$BASE" ] && die "BASE is unset; bogus $CONFIG ?"
+[ -d "$BASE" ] || die "$BASE is not a directory; bogus $CONFIG ?"
+cd "$BASE" || die "$BASE is inaccessible"
+
config LIVE "$BASE/live"
config UPPER "$BASE/root"
config WORK "$BASE/work"
config CABLES ""
config START "networking ssh"
config SUBSHELL /bin/sh
-config STOP ""
-# Setup virtual cabling and subhost's /etc/network/interfaces
+# Setup virtual cabling
setup_veth_cables $NAME $CABLES
# Set up the mount for this subhost, including a new tmpfs on its /run
+# and a default $UPPER/etc/network/interfaces if needed
echo setup_overlay "$NAME" "$LIVE" "$LOWER" "$UPPER" "$WORK"
setup_overlay "$NAME" "$LIVE" "$LOWER" "$UPPER" "$WORK"
exithandler() {
ip netns del $NAME
- umount -R "$LIVE"
+ [ "$LOWER" != "$LIVE" ] && umount -R "$LIVE"
+ [ -f "${UPPER%% *}" ] && [ -x "${UPPER%% *}" ] && \
+ env ACTION=teardown $UPPER
}
trap "exithandler" 0
CMD="unshare -fp --mount-proc ip netns exec $NAME chroot $LIVE /bin/sh"
echo "$CMD"
+config RAM_SIZE 50M
+
cat <<EOF | $CMD
set -x
mount -t proc proc /proc
+mount -t devpts devpts /dev/pts
+mount -t sysfs sysfs /sys
+if [ "$RAM_SIZE" != "none" ] && ! grep -q '/run tmpfs' /proc/mounts ; then
+ mount -t tmpfs -osize=$RAM_SIZE,mode=755 tmpfs /run
+fi
for srv in $START ; do service \$srv start ; done
+dummy_service() {
+ [ \$# -gt 3 ] && return 0
+ echo "Starting dummy service" >&2
+ set +x
+ [ -p /run/dummy_service ] || mkfifo /run/dummy_service
+ ( printf dummy_service > /proc/self/comm ; read X < /run/dummy_service ) &
+ set -x
+}
+dummy_service /proc/*/comm
exec /.reaper $NAME
EOF
echo "EXITED $CMD"