=== modified file 'sbin/ns_run'
--- sbin/ns_run	2020-12-18 04:07:00 +0000
+++ sbin/ns_run	2020-12-18 00:22:04 +0000
@@ -1,138 +1,14 @@
-#!/command/execlineb -s1
-
-## usage: ns_run <root_directory> <executable> [<arg1> ...]
-##
-## Creates isolated namespace/container with given root and runs given
-## executable in it.
-## Environment variables used:
-##   HOST - hostname to set
-##   NS_ROOT - where to bind-mount the root directory
-##   NS_EXTRA - extra execline script to run after setting up the namespaces
-##              and mounting essential filesystems but before entering it
-##              and unmounting host filesystem
-##   NS_FSTAB - file with extra mounts to make after running above script
-##   NS_TMPFS - place to store binaries in the container that are run
-##              before dropping privs, relative path from new root
-##   NS_BIN - directory to get said binaries from; currently needs:
-##            - `if` from execline
-##            - busybox with `umount` and `chpst` functions
-##            - anything you wish to call before and for dropping privs,
-##              eg. s6-applyuidgid
-##            All statically linked of course.
-
-# import variables from environment, with defaults
-multisubstitute {
-	importas -D mnt/ns NS_TMPFS
-	importas -D /mnt/volumes/containers/bin NS_BIN
-	importas -D /mnt/chroot NS_ROOT
-}
-
-# check we are PID1 (in a new PID namespace)
+#!/command/execlineb -S0
 getpid PID
 ifelse { importas -i PID PID test 1 -ne $PID } {
 	fdmove -c 1 2
 	echo "ns_run: fatal: not PID 1"
-	exit 111
+	exit 2
 }
 unexport PID
 
-
 unshare -m -u -i  # new mount, UTS and IPC namespaces
 foreground { importas -i HOST HOST hostname $HOST }
-
-# We will generate final script we exec into before we start mounting anything,
-# so only the mountpoints that exist at this point will get unmounted and
-# everything we will mount below will stay.
-backtick -i NS_FINAL_SCRIPT {
-	# Generate execline script that performs pivot_root
-	# and umounts all the filesystems not used by the container
-	# formerly: /root/ns_execline.zsh $@
-
-	if {
-		printf "%s\n"
-		"if { pivot_root . \$NS_TMPFS/oldroot }"
-	}
-	if {
-		ns_umount_script.awk
-		-vROOT=/$NS_TMPFS/oldroot
-		-vBIN=/$NS_TMPFS/bin
-		/proc/self/mountinfo
-	}
-	if { printf "%s\n" "./$NS_TMPFS/bin/busybox chpst -/ ." }
-	# quote all the arguments we got for interpretation by execline
-	forx -o 0 X { $@ } importas -i X X s6-quote $X
-}
-
-# mount and enter the chroot directory
-if { mount --rbind $1 $NS_ROOT }
-cd $NS_ROOT
-
-## this will be better handled by NS_EXTRA script
-## and perhaps /etc/resolv.conf -> /run/resolv.conf symlink
-# foreground { cp /etc/resolv.conf etc/ }
-
-# /proc
-if { mount -t proc proc proc }
-
-# /dev
-if { s6-mount -nwt tmpfs -o nosuid,dev,mode=0755 dev dev }
-if { mknod -m 666 dev/null c 1 3 }
-if { mknod -m 666 dev/full c 1 7 }
-if { mknod -m 666 dev/ptmx c 5 2 }
-if { mknod -m 644 dev/random c 1 8 }
-if { mknod -m 644 dev/urandom c 1 9 }
-if { mknod -m 666 dev/zero c 1 5 }
-if { mknod -m 666 dev/tty c 5 0 }
-
-# shm, pts and mqueue are provided below
-# also have some convenience dirs in place for optionally bind-mounting them
-if {
-	mkdir
-	dev/shm
-	dev/pts
-	dev/mqueue
-
-	dev/block
-	dev/bus
-	dev/char
-	dev/dri
-	dev/input
-	dev/loop
-	dev/net
-	dev/snd
-	dev/usb
-
-}
-if { mount -t devpts devpts dev/pts }
-if { s6-mount -nwt tmpfs -o nosuid,nodev,mode=1777 shm dev/shm }
-if { s6-mount -nwt mqueue -o nosuid,nodev,noexec,relatime mqueue dev/mqueue }
-# leave /dev read-write for now, so stuff can be added by scripts below
-
-# mountpoint for privileged operations and pivot_root
-if { s6-mount -nwt tmpfs -o nosuid,nodev,mode=700 mnt_ns $NS_TMPFS }
-if { mkdir $NS_TMPFS/oldroot $NS_TMPFS/bin }
-#if { s6-hiercopy $NS_BIN $NS_TMPFS/bin }
-if { s6-mount -n -o bind,ro $NS_BIN ${NS_TMPFS}/bin }
-
-# container-specific setup provided in environment
-if {
-	if -t { s6-test -V NS_EXTRA }
-	importas -i NS_EXTRA NS_EXTRA
-	execlineb -c $NS_EXTRA
-}
-
-if {
-	if -t { s6-test -V NS_FSTAB }
-	importas -i NS_FSTAB NS_FSTAB
-	mount -a --fstab $NS_FSTAB
-}
-
-# now we can make /dev immutable
-if { mount -o remount,ro dev }
-
-# exec into the script we generated above, it:
-# * does pivot_root to change rootdir
-# * umounts all undesired filesystems
-# * execs into $@
-importas -i NS_FINAL_SCRIPT NS_FINAL_SCRIPT
-execlineb -c $NS_FINAL_SCRIPT
+fdmove -c 3 0  # store original stdin as we are calling pipelined script
+pipeline -d { /root/ns_execline.zsh $@ }
+execlineb /dev/stdin

=== removed file 'sbin/ns_umount_script.awk'
--- sbin/ns_umount_script.awk	2020-12-18 04:07:00 +0000
+++ sbin/ns_umount_script.awk	1970-01-01 00:00:00 +0000
@@ -1,58 +0,0 @@
-#!/usr/bin/awk -f
-function el_quote(s) {
-	RESULT="\"${${${1}//\\/\\\\}//\"/\\\"}\""
-	gsub(/\\/, "\\\\", s);  # first double all backslashes
-	gsub(/"/, "\\\"", s);  # then escape quote marks
-	return "\"" s "\""  # then surround with quote marks
-}
-
-BEGIN {
-	# check if necessary variables were defined
-	if(BIN == "") { exit 100 }
-	if(ROOT == "") { exit 100 }
-
-	# quote common stings
-	IF = el_quote(BIN "/if")
-	UMOUNT = el_quote(BIN "/busybox") " umount"
-
-	# mount IDs seem to be unsigned, so let's use -1 to signify not found
-	max_id = -1
-	root_id = -1
-}
-
-# read in /proc/self/mountinfo
-$5 == "/" { root_id = $1 }
-{
-	max_id = max_id < $1 ? $1 : max_id
-	parents[$1] = $2
-	mountpoints[$1] = $5
-}
-
-function _if(opts, s) {
-	return IF opts " { " s " } "
-}
-
-function umount(opts, s) {
-	return UMOUNT opts " " el_quote(ROOT s)
-}
-
-function print_umount(mtp){
-	print _if("", \
-	      _if(" -n -t",  umount("", mtp)) \
-	      umount(" -l", mtp) \
-      )
-}
-
-function recursively_umount(mount_id,    id) {
-	for(id=max_id; id>=0; id--){
-		if(parents[id] == mount_id){
-			recursively_umount(id)
-		}
-	}
-	print_umount(mountpoints[mount_id])
-}
-
-END{
-	if(root_id == -1) { exit 111 }
-	recursively_umount(root_id)
-}