mmgen-geek-tools/scripts/armbian_rootenc_setup.sh

#!/bin/bash

PATH="$PATH:/usr/sbin:/sbin"
RED="\e[31;1m" GREEN="\e[32;1m" YELLOW="\e[33;1m" BLUE="\e[34;1m" PURPLE="\e[35;1m" RESET="\e[0m"
PROGNAME=$(basename $0)
TITLE='Armbian Encrypted  Root Filesystem          Setup'
CONFIG_VARS='
	ARMBIAN_IMAGE
	BOOTPART_LABEL
	ROOTFS_NAME
	DISK_PASSWD
	UNLOCKING_USERHOST
	IP_ADDRESS
	ADD_ALL_MODS
	USE_LOCAL_AUTHORIZED_KEYS
'
STATES='
	card_partitioned
	bootpart_copied
	bootpart_label_created
	rootpart_copied
	target_configured
'
USER_OPTS_INFO="
	NO_CLEANUP                 no cleanup of mounts after program run
	FORCE_REBUILD              force full rebuild
	FORCE_RECONFIGURE          force reconfiguration
	FORCE_REFORMAT_ROOT        force reformat of encrypted root partition
	ADD_ALL_MODS               add all currently loaded modules to initramfs
	USE_LOCAL_AUTHORIZED_KEYS  use local 'authorized_keys' file
	PARTITION_ONLY             partition and create filesystems only
	ERASE                      zero boot sector, boot partition and beginning of root partition
	ROOTENC_REUSE_FS           reuse existing filesystems (for development only)
	ROOTENC_TESTING            developer tweaks
	ROOTENC_PAUSE              pause along the way
	ROOTENC_IGNORE_APT_ERRORS  continue even if apt update fails
"
RSYNC_VERBOSITY='--info=progress2'

print_help() {
	echo "  ${PROGNAME^^}: Create an Armbian image with encrypted root filesystem
  USAGE:           $PROGNAME [options] <SD card device name>
  OPTIONS:   '-h'  Print this help message
             '-C'  Don't perform unmounts or clean up build directory at exit
             '-d'  Produce tons of debugging output
             '-f'  Force reconfiguration of target system
             '-F'  Force a complete rebuild of target system
             '-m'  Add all currently loaded modules to the initramfs (may help
                   fix blank screen on bootup issues)
             '-p'  Partition and create filesystems only.  Do not copy data
             '-R'  Force reformat of encrypted root partition
             '-s'  Use 'authorized_keys' file from working directory, if available
                   (see below)
             '-v'  Be more verbose
             '-u'  Perform an 'apt upgrade' after each 'apt update'
             '-z'  Erase boot sector and first partition of SD card before partitioning
                   (an extra paranoia step, but it can’t hurt)

  For non-interactive operation, set the following variables in your environment
  or on the command line:

      ROOTFS_NAME        - device mapper name of target root filesystem
      IP_ADDRESS         - IP address of target (set to 'dhcp' for dynamic IP
                           or 'none' to disable remote SSH unlocking support)
      BOOTPART_LABEL     - Boot partition label of target
      DISK_PASSWD        - Disk password of target root filesystem
      UNLOCKING_USERHOST - USER@HOST of remote unlocking host


                            INSTRUCTIONS FOR USE

  This script must be invoked as superuser on a running Armbian system.
  Packages will be installed using APT, so the system must be Internet-
  connected and its clock correctly set.

  If remote unlocking via SSH is desired, the unlocking host must be reachable.
  Alternatively, SSH public keys for the unlocking host or hosts may be listed
  in the file 'authorized_keys' in the current directory.  This file has the
  same format as a standard SSH 'authorized_keys' file.

  Architecture of host and target (e.g. 64-bit or 32-bit ARM) must be the same.

  For best results, the host and target hardware should also be identical or
  similar.  Building on a host with more memory than the target, for example,
  may lead to disk unlocking failure on the target.  For most users, who’ll be
  building for the currently-running board, this point is a non-issue.

  1. Place an Armbian boot image file for the target system in the current
     directory.  For best results, the image file should match the Debian
     or Ubuntu release of the host system.

  2. Insert a USB card reader with a blank micro-SD card for the target
     system into the host’s USB port.

  3. Determine the SD card’s device name using 'dmesg' or 'lsblk'.

  4. Invoke the script with the device name as argument.  If any options
     are desired, they must precede the device name.

  If the board has an eMMC, it may be used as the target device instead of
  an SD card." | less
}

pause() {
	echo -ne $GREEN'(Press any key to continue)'$RESET >&$stderr_dup
	read
	no_fmsg=1
}
_debug_pause() { [ "$ROOTENC_PAUSE" ] && pause; true; }
imsg()      { echo -e "$1" >&$stdout_dup; no_fmsg=1; }
imsg_nonl() { echo -ne "$1" >&$stdout_dup; no_fmsg=1; }
tmsg()      {
	no_fmsg=1
	[ "$ROOTENC_TESTING" ] || return 0
	echo -e "$1" >&$stdout_dup
}
warn()      { echo -e "$YELLOW$1$RESET" >&$stdout_dup; no_fmsg=1; }
warn_nonl() { echo -ne "$YELLOW$1$RESET" >&$stdout_dup; no_fmsg=1; }
rmsg()      { echo -e "$RED$1$RESET" >&$stdout_dup; no_fmsg=1; }
gmsg()      { echo -e "$GREEN$1$RESET" >&$stdout_dup; no_fmsg=1; }
pu_msg()    { echo -e "$PURPLE$1$RESET" >&$stdout_dup; no_fmsg=1; }

do_partprobe() {
	if [ "$VERBOSE" ]; then partprobe; else partprobe 2>/dev/null; fi
	no_fmsg=1
}

_show_output() { [ "$VERBOSE" ] || exec 1>&$stdout_dup 2>&$stderr_dup; }
_hide_output() { [ "$VERBOSE" ] || exec &>'/dev/null'; }

bail() { exit; }
die() {
	echo -e "$RED$1$RESET" >&$stdout_dup
	no_fmsg=1
	exit 1
}

_fmsg() {
	local funcname=$1 errval=$2 res
	if [ "${funcname:0:1}" == '_' -o "$no_fmsg" ]; then
		no_fmsg=
		return 0
	fi
	if [ "$errval" -eq 0 ]; then res='OK'; else res="False ($errval)"; fi
	printf "$BLUE%-32s $res$RESET\n" "$funcname" >&$stdout_dup
}

_sigint_handler() {
	warn "\nExiting at user request"
	usr_exit=1
	exit 1
}

_exit_handler() {
	local err=$?
	_show_output
	[ $err -ne 0 -a -z "$usr_exit" ] && {
		rmsg "$SCRIPT_DESC exiting with error (exit code $err)"
	}
	return $err
}

_do_header() {
	echo
	local reply
	if banner=$(toilet --filter border --filter gay --width 51 -s -f smbraille "$TITLE" 2>/dev/null); then
		while read reply; do
			echo -e "             $reply"
		done <<-EOF
			$banner
		EOF
	else
		echo -n '                  '
		echo $TITLE
		echo
	fi
	echo "                      For detailed usage information,"
	echo "                        invoke with the '-h' switch"
	echo
}

_warn_user_opts() {
	local out
	while read opt text; do
		[ "$opt" ] || continue
		[ $(eval echo -n \$$opt) ] && out+="  + $text\n"
	done <<-EOF
		$USER_OPTS_INFO
	EOF
	[ "$out" ] && {
		warn      "  The following user options are in effect:"
		warn_nonl "${out}"
	}
}

_set_host_vars() {
	BUILD_DIR='armbian_rootenc_build'
	SRC_ROOT="$BUILD_DIR/src"
	BOOT_ROOT="$BUILD_DIR/boot"
	TARGET_ROOT="$BUILD_DIR/target"
	CONFIG_VARS_FILE="$BOOT_ROOT/.rootenc_config_vars"
	host_distro=$(lsb_release --short --codename)
	host_kernel=$(ls '/boot' | egrep '^vmlinu[xz]') # allow 'vmlinux' or 'vmlinuz'
}

check_sdcard_name_and_params() {
	local dev chk
	dev=$1
	[ "$dev" ] || die "You must supply a device name"
	[ "${dev:0:5}" == '/dev/' ] || dev="/dev/$dev"
	[ -e "$dev" ] || die "$dev does not exist"
	chk="$(lsblk --noheadings --nodeps --list --output=TYPE $dev 2>/dev/null)"
	[ "$chk" != 'disk' ] && {
		[ "$chk" == 'part' ] && die "$dev is a partition, not a block device!"
		die "$dev is not a block device!"
	}
	local pttype size nodos oversize removable non_removable part_sep
	pttype=$(blkid --output=udev $dev | grep TYPE | cut -d '=' -f2)
	size="$(lsblk --noheadings --nodeps --list --output=SIZE --bytes $dev 2>/dev/null)"
	removable="$(lsblk --noheadings --nodeps --list --output=RM $dev 2>/dev/null)"
	nodos=$([ "$pttype" -a "$pttype" != 'dos' ] && echo "Partition type is ${pttype^^}")
	oversize=$([ $size -gt 137438953472 ] && echo 'Size is > 128GiB')
	non_removable=$([ $removable -ne 0 ] || echo 'Device is non-removable')
	SD_INFO="$(lsblk --noheadings --nodeps --list --output=VENDOR,MODEL,SIZE $dev 2>/dev/null)"
	SD_INFO=${SD_INFO//  / }
	[ "$nodos" -o "$oversize" -o "$non_removable" ] && {
		warn "  $dev ($SD_INFO) doesn’t appear to be an SD card"
		warn "  for the following reasons:"
		[ "$non_removable" ] && warn "      $non_removable"
		[ "$nodos" ] && warn "      $nodos"
		[ "$oversize" ] && warn "      $oversize"
		_user_confirm '  Are you sure this is the correct device of your blank SD card?' 'no'
	}
	SDCARD_DEVNAME=${dev:5}
	[ "${SDCARD_DEVNAME%[0-9]}" == $SDCARD_DEVNAME ] || part_sep='p'
	BOOT_DEVNAME=$SDCARD_DEVNAME${part_sep}1
	ROOT_DEVNAME=$SDCARD_DEVNAME${part_sep}2
	[ "$SDCARD_DEVNAME" ] || die 'You must supply a device name for the SD card!'
	pu_msg "Will write to target $dev ($SD_INFO)"
}

_get_user_var() {
	local var desc dfl prompt pat pat_errmsg vtest cprompt seen_prompt reply redo
	var=$1 desc=$2 dfl=$3 prompt=$4 pat=$5 pat_errmsg=$6 vtest=$7
	while true; do
		[ -z "${!var}" -o "$seen_prompt" -o "$redo" ] && {
			if [ "$seen_prompt" ]; then
				echo -n "  Enter $desc: "
			else
				cprompt=
				while read reply; do
					cprompt+="  ${reply## }\n"
				done <<-EOF
					$prompt
				EOF
				echo
				if [ "$dfl" ]; then
					printf "${cprompt:0:-2} " "$dfl"
				else
					echo -ne "${cprompt:0:-2} "
				fi
				seen_prompt=1
			fi
			eval "read $var"
		}
		redo=1
		[ -z "${!var}" -a "$dfl" ] && eval "$var=$dfl"
		[ "${!var}" ] || {
			rmsg "  $desc must not be empty"
			continue
		}
		[ "$pat" ] && {
			echo "${!var}" | egrep -qi "$pat" || {
				rmsg "  ${!var}: $pat_errmsg"
				continue
			}
		}
		[ "$vtest" ] && {
			$vtest || continue
		}
		break
	done
}

_get_user_vars() {
	_get_user_var 'IP_ADDRESS' 'IP address' '' \
		"Enter the IP address of the target machine.
		Enter 'dhcp' for a dynamic IP or 'none' for no remote SSH unlocking support
		IP address:" \
		'^(dhcp|none|[0-9]{1,3}\.[0-9]{1,3}\.[0-9]+\.[0-9]{1,3})$' \
		'malformed IP address'
	IP_ADDRESS=${IP_ADDRESS,,}

	_get_user_var 'BOOTPART_LABEL' 'boot partition label' 'ARMBIAN_BOOT' \
		"Enter a boot partition label for the target machine,
		or hit ENTER for the default (%s): " \
		'^[A-Za-z0-9_]{1,16}$' \
		"Label must contain no more than 16 characters in the set 'A-Za-z0-9_'"

	_get_user_var 'ROOTFS_NAME' 'root filesystem device name' 'rootfs' \
		"Enter a device name for the encrypted root filesystem,
		or hit ENTER for the default (%s):" \
		'^[a-z0-9_]{1,48}$' \
		"Name must contain no more than 48 characters in the set 'a-z0-9_'" \
		'_test_rootfs_mounted'

	_get_user_var 'DISK_PASSWD' 'disk password' '' \
		"Choose a simple disk password for the installation process.
		Once your encrypted system is up and running, you can change
		the password using the 'cryptsetup' command.
		Enter password:" \
		'^[A-Za-z0-9_ ]{1,10}$' \
		"Temporary disk password must contain no more than 10 characters in the set 'A-Za-z0-9_ '"

	if [ "$IP_ADDRESS" == 'none' ]; then
		UNLOCKING_USERHOST=
	elif [ -e 'authorized_keys' -a "$USE_LOCAL_AUTHORIZED_KEYS" ]; then
		UNLOCKING_USERHOST=
	else
		_get_user_var 'UNLOCKING_USERHOST' 'USER@HOST' '' \
			"Enter the user@host of the machine you'll be unlocking from:" \
			'\S+@\S+' \
			'malformed USER@HOST' \
			'_test_unlocking_host_available'
	fi
	true
}

_test_rootfs_mounted() {
	[ -e "/dev/mapper/$ROOTFS_NAME" ] && {
		local mnt=$(lsblk --list --noheadings --output=MOUNTPOINT /dev/mapper/$ROOTFS_NAME)
		[ "$mnt" ] && {
			rmsg "  Device '$ROOTFS_NAME' is in use and mounted on $mnt"
			return 1
		}
	}
	return 0
}

_test_unlocking_host_available() {
	local ul_host=${UNLOCKING_USERHOST#*@}
	ping -c1 $ul_host &>/dev/null || {
		rmsg "  Unable to ping host '$ul_host'"
		return 1
	}
}

_test_sdcard_mounted() {
	local chk="$(lsblk --noheadings --list --output=MOUNTPOINT /dev/$SDCARD_DEVNAME)"
	[ -z "$chk" ] || {
		lsblk --output=NAME,SIZE,TYPE,FSTYPE,MOUNTPOINT /dev/$SDCARD_DEVNAME
		die "Device /dev/$SDCARD_DEVNAME has mounted partitions!"
	}
}

get_authorized_keys() {
	[ -e 'authorized_keys' -a "$USE_LOCAL_AUTHORIZED_KEYS" ] || {
		rsync "$UNLOCKING_USERHOST:.ssh/id_*.pub" 'authorized_keys'
	}
}

_apt_update() {
	[ "$ROOTENC_IGNORE_APT_ERRORS" ] && set +e
	apt --yes update
	[ "$APT_UPGRADE" ] && apt --yes upgrade
	[ "$ROOTENC_IGNORE_APT_ERRORS" ] && set -e
	true
}

_print_pkgs_to_install() {
	local pkgs pkgs_ssh
	case $1 in
		'host')
			case "$host_distro" in
				focal|bionic|buster) pkgs='cryptsetup-bin ed' ;;
				*)                   pkgs='cryptsetup ed'
									 warn "Warning: unrecognized host distribution '$host_distro'" ;;
			esac ;;
		'target')
			case "$target_distro" in
				focal|buster) pkgs='cryptsetup-initramfs' pkgs_ssh='dropbear-initramfs' ;;
				bionic)       pkgs='cryptsetup'           pkgs_ssh='dropbear-initramfs' ;;
				*)            pkgs='cryptsetup'           pkgs_ssh='dropbear'
							  warn "Warning: unrecognized target distribution '$target_distro'" ;;
			esac
			[ "$IP_ADDRESS" != 'none' ] && pkgs+=" $pkgs_ssh" ;;
	esac
	for i in $pkgs; do
		dpkg -l $i 2>/dev/null | grep -q ^ii || echo $i
	done
}

apt_install_host() {
	local pkgs=$(_print_pkgs_to_install 'host')
	[ "$pkgs" ] && {
		_apt_update
		apt --yes install $pkgs
	}
	true
}

create_build_dir() {
	mkdir -p $BUILD_DIR
	mkdir -p $SRC_ROOT
	mkdir -p $BOOT_ROOT
	mkdir -p $TARGET_ROOT
}

umount_target() {
	for i in $BOOT_ROOT $TARGET_ROOT; do
		while mountpoint -q $i; do
			umount -Rl $i
		done
	done
}

remove_build_dir() {
	[ -d $TARGET_ROOT ] && rmdir $TARGET_ROOT
	[ -d $BOOT_ROOT ] && rmdir $BOOT_ROOT
	[ -d $SRC_ROOT ] && rmdir $SRC_ROOT
	[ -d $BUILD_DIR ] && rmdir $BUILD_DIR
	true
}

_get_device_maps() {
	local dm_type=$1
	local varname="device_maps_${dm_type}"
	eval "$varname="
	local data=$(lsblk --list --noheadings --output=KNAME,MOUNTPOINT | egrep '^dm-[0-9]')
	while read kname mountpoint; do
		[ "$dm_type" == 'unmounted' -a "$mountpoint" ] && continue
		[ "$dm_type" == 'mounted_on_target' -a \
			"${mountpoint: -${#TARGET_ROOT}}" != "$TARGET_ROOT" ] && continue
		eval "$varname+=/dev/$kname "
	done <<-EOF
		$data
	EOF
	tmsg "$varname=[${!varname}]"
}

_close_device_maps() {
	local dm_type=$1
	local varname="device_maps_${dm_type}"
	for i in ${!varname}; do
		tmsg "closing $i"
		cryptsetup status $i > '/dev/null' && cryptsetup luksClose $i
	done
}

_preclean() {
	close_loopmount
	_get_device_maps 'unmounted'
	_close_device_maps 'unmounted'
	_get_device_maps 'mounted_on_target'
	umount_target
	_close_device_maps 'mounted_on_target'
	remove_build_dir
}

_clean() {
	local err=$?
	[ $err -ne 0 -a -z "$usr_exit" ] && rmsg "$SCRIPT_DESC exiting with error (exit code $err)"
	pu_msg "Cleaning up, please wait..."
	_show_output
	close_loopmount
	_get_device_maps 'mounted_on_target'
	umount_target
	update_config_vars_file
	_close_device_maps 'mounted_on_target'
	[ -e 'authorized_keys' -a -z "$USE_LOCAL_AUTHORIZED_KEYS" ] && shred -u 'authorized_keys'
	remove_build_dir
}

get_armbian_image() {
	ARMBIAN_IMAGE="$(ls *.img)"
	[ "$ARMBIAN_IMAGE" ] || die 'You must place an Armbian image in the current directory!'
	local count=$(echo "$ARMBIAN_IMAGE" | wc -l)
	[ "$count" == 1 ] || die "More than one image file present!:\n$ARMBIAN_IMAGE"
}

_confirm_user_vars() {
	echo
	echo "  Armbian image:                $ARMBIAN_IMAGE"
	echo "  Target device:                /dev/$SDCARD_DEVNAME ($SD_INFO)"
	echo "  Root filesystem device name:  /dev/mapper/$ROOTFS_NAME"
	echo "  Target IP address:            $IP_ADDRESS"
	echo "  Boot partition label:         $BOOTPART_LABEL"
	echo "  Disk password:                $DISK_PASSWD"
	[ "$UNLOCKING_USERHOST" ] && echo "  user@host of unlocking machine: $UNLOCKING_USERHOST"
	echo
	_user_confirm '  Are these settings correct?' 'yes'
}

setup_loopmount() {
	LOOP_DEV=$(losetup -f)
	losetup -P $LOOP_DEV $ARMBIAN_IMAGE
	mount ${LOOP_DEV}p1 $SRC_ROOT
	START_SECTOR=$(fdisk -l $LOOP_DEV -o Start | tail -n1 | tr -d ' ') # usually 32768
	BOOT_SECTORS=409600 # 200MB
}

_umount_with_check() {
	mountpoint -q $1 && umount $1
}

update_config_vars_file() {
	mount "/dev/$BOOT_DEVNAME" $BOOT_ROOT
	_print_config_vars $CONFIG_VARS_FILE
	umount $BOOT_ROOT
}

_print_states() {
	for i in $STATES; do
		echo $i: ${!i}
	done
}

_update_state_from_config_vars() {
	[ -e $CONFIG_VARS_FILE ] || return 0
	local reply
	while read reply; do eval "c$reply"; done <<-EOF
		$(cat $CONFIG_VARS_FILE)
	EOF
	local saved_states cfgvar_changed
	saved_states="$(_print_states)"
	cfgvar_changed=
	[ $cARMBIAN_IMAGE != $ARMBIAN_IMAGE ]    && cfgvar_changed+=' ARMBIAN_IMAGE' card_partitioned='n'
	[ $cBOOTPART_LABEL != $BOOTPART_LABEL ]  && cfgvar_changed+=' BOOTPART_LABEL' bootpart_label_created='n'
	[ $cROOTFS_NAME != $ROOTFS_NAME ]        && cfgvar_changed+=' ROOTFS_NAME' target_configured='n'
	[ $cDISK_PASSWD != $DISK_PASSWD ]        && cfgvar_changed+=' DISK_PASSWD' rootpart_copied='n'
	[ "$UNLOCKING_USERHOST" -a "$cUNLOCKING_USERHOST" != "$UNLOCKING_USERHOST" ] && {
		cfgvar_changed+=' UNLOCKING_USERHOST' target_configured='n'
	}
	[ $cIP_ADDRESS != $IP_ADDRESS ]          && cfgvar_changed+=' IP_ADDRESS' target_configured='n'
	[ "$cADD_ALL_MODS" != "$ADD_ALL_MODS" ]  && cfgvar_changed+=' ADD_ALL_MODS' target_configured='n'
	[ "$IP_ADDRESS" -a "$cUSE_LOCAL_AUTHORIZED_KEYS" != "$USE_LOCAL_AUTHORIZED_KEYS" ] && {
		cfgvar_changed+=' USE_LOCAL_AUTHORIZED_KEYS' target_configured='n'
	}

	[ $card_partitioned == 'n' ] && {
		bootpart_copied='n'
		bootpart_label_created='n'
		rootpart_copied='n'
		target_configured='n'
	}
	[ $bootpart_copied == 'n' ] && bootpart_label_created='n'
	[ $rootpart_copied == 'n' ] && target_configured='n'

	[ "$saved_states" != "$(_print_states)" ] && {
		warn "Install state altered due to changed config vars:$cfgvar_changed"
		for i in $STATES; do
			if [ "${!i}" == 'n' ]; then
				imsg "  $i: ${RED}no$RESET"
			else
				imsg "  $i: ${GREEN}yes$RESET"
			fi
		done
		_delete_state_files
	}
	true
}

_add_state_file() {
	local state=$1 cmd=$2
	if [ "$cmd" == 'target' ]; then
		touch "$TARGET_ROOT/boot/.rootenc_install_state/$state"
	else
		[ "$cmd" == 'mount' ] && mount "/dev/$BOOT_DEVNAME" $BOOT_ROOT
		mkdir -p "$BOOT_ROOT/.rootenc_install_state"
		touch "$BOOT_ROOT/.rootenc_install_state/$state"
		[ "$cmd" == 'mount' ] && umount $BOOT_ROOT
	fi
	eval "$state='y'"
	tmsg "added state file '$state'"
}

_delete_state_files() {
	for i in $STATES; do
		local fn="$BOOT_ROOT/.rootenc_install_state/$i"
		[ ${!i} == 'n' -a -e $fn ] && /bin/rm $fn
	done
	true
}

_get_state_from_state_files() {
	for i in $STATES; do
		if [ -e "$BOOT_ROOT/.rootenc_install_state/$i" ]; then
			eval "$i=y"
		else
			eval "$i=n"
		fi
	done
}

_print_state_from_state_files() {
	imsg 'Install state:'
	for i in $STATES; do
		if [ -e "$BOOT_ROOT/.rootenc_install_state/$i" ]; then
			imsg "  $i: ${GREEN}yes$RESET"
		else
			imsg "  $i: ${RED}no$RESET"
		fi
	done
}

check_install_state() {
	for i in $STATES; do eval "$i=n"; done
	if [ "$FORCE_REBUILD" ]; then
		return
	else
		do_partprobe
		lsblk --noheadings --list /dev/$SDCARD_DEVNAME -o 'NAME' | grep -q $BOOT_DEVNAME || return 0
		lsblk --noheadings --list /dev/$BOOT_DEVNAME -o 'FSTYPE' | grep -q 'ext4' || return 0

		mount "/dev/$BOOT_DEVNAME" $BOOT_ROOT
		_get_state_from_state_files
		if [ "$target_configured" == 'y' -a "$FORCE_RECONFIGURE" ]; then
			target_configured='n'
			_delete_state_files
		fi
		_print_state_from_state_files
		_update_state_from_config_vars
		_umount_with_check $BOOT_ROOT
	fi
}

close_loopmount() {
	while mountpoint -q $SRC_ROOT; do
		umount $SRC_ROOT
	done
	for i in $(losetup --noheadings --raw --list -j $ARMBIAN_IMAGE | awk '{print $1}'); do
		losetup -d $i
	done
}

_user_confirm() {
	local prompt1 prompt2 dfl_action reply
	prompt1=$1 dfl_action=$2
	if [ "$dfl_action" == 'yes' ]; then
		prompt2='(Y/n)'
	else
		prompt2='(y/N)'
	fi
	imsg_nonl "$prompt1 $prompt2 "
	read -n1 reply
	[ "$reply" ] && imsg ''
	[ "$dfl_action" == 'yes' -a -z "$reply" ] && return
	[ "$reply" == 'y' -o "$reply" == 'Y' ] && return
	warn "Exiting at user request"
	usr_exit=1
	exit 1
}

erase_boot_sector_and_first_partition() {
	local sectors count
	sectors=$((START_SECTOR+BOOT_SECTORS+100))
	count=$(((sectors/8192)+1))
	pu_msg "Erasing up to beginning of second partition ($sectors sectors, ${count}M):"
	_show_output
	dd  if=/dev/zero \
		of=/dev/$SDCARD_DEVNAME \
		status=progress \
		bs=$((512*8192)) \
		count=$count
	_hide_output
}

create_partition_label() {
	pu_msg "Creating new partition label on /dev/$SDCARD_DEVNAME"
	local fdisk_cmds="o\nw\n"
	set +e
	echo -e "$fdisk_cmds" | fdisk "/dev/$SDCARD_DEVNAME"
	set -e
	do_partprobe
}

copy_boot_loader() {
	local count
	count=$((START_SECTOR/2048))
	pu_msg "Copying boot loader ($START_SECTOR sectors, ${count}M):"
	_show_output
	dd  if=$ARMBIAN_IMAGE \
		of=/dev/$SDCARD_DEVNAME \
		status=progress \
		bs=$((512*2048)) \
		count=$count
	_hide_output
	do_partprobe
}

_print_config_vars() {
	local outfile=$1
	local data="$(for i in $CONFIG_VARS; do echo "$i=${!i}"; done)"
	if [ "$outfile" ]; then echo "$data" > $outfile; else echo "$data"; fi
}

partition_sd_card() {
	local p1_end p2_start fdisk_cmds bname rname fstype
	p1_end=$((START_SECTOR+BOOT_SECTORS-1))
	p2_start=$((p1_end+1))
	fdisk_cmds="o\nn\np\n1\n$START_SECTOR\n$p1_end\nn\np\n2\n$p2_start\n\nw\n"

	set +e
	echo -e "$fdisk_cmds" | fdisk "/dev/$SDCARD_DEVNAME"
	set -e
	do_partprobe

	bname="$(lsblk --noheadings --list --output=NAME /dev/$BOOT_DEVNAME)"
	[ "$bname" == $BOOT_DEVNAME ] || die 'Partitioning failed!'

	rname="$(lsblk --noheadings --list --output=NAME /dev/$ROOT_DEVNAME)"
	[ "$rname" == $ROOT_DEVNAME ] || die 'Partitioning failed!'

	# filesystem is required by call to _add_state_file(), so we must create it here
	fstype=$(lsblk --noheadings --list --output=FSTYPE "/dev/$BOOT_DEVNAME")
	[ "$fstype" == 'ext4' -a "$ROOTENC_REUSE_FS" ] || mkfs.ext4 -F "/dev/$BOOT_DEVNAME"
	do_partprobe

	_add_state_file 'card_partitioned' 'mount'
}

_do_partition() {
	imsg "All data on /dev/$SDCARD_DEVNAME ($SD_INFO) will be destroyed!!!"
	_user_confirm 'Are you sure you want to continue?' 'no'
	if [ "$ERASE" ]; then
		erase_boot_sector_and_first_partition
	else
		create_partition_label
	fi
	copy_boot_loader
	partition_sd_card
}

copy_system_boot() {
	[ "$PARTITION_ONLY" ] && {
		_add_state_file 'bootpart_copied' 'mount'
		return
	}
	mount "/dev/$BOOT_DEVNAME" $BOOT_ROOT
	pu_msg "Copying files to boot partition:"
	_show_output
	rsync $RSYNC_VERBOSITY --archive $SRC_ROOT/boot/* $BOOT_ROOT
	_hide_output
	[ -e "$BOOT_ROOT/boot" ] || (cd $BOOT_ROOT && ln -s . 'boot')
	_add_state_file 'bootpart_copied'
	umount $BOOT_ROOT
}

create_bootpart_label() {
	e2label "/dev/$BOOT_DEVNAME" "$BOOTPART_LABEL"
	do_partprobe
	_add_state_file 'bootpart_label_created' 'mount'
}

copy_system_root() {
	if [ "$FORCE_REFORMAT_ROOT" ] || ! cryptsetup isLuks "/dev/$ROOT_DEVNAME"; then
		pu_msg "Formatting encrypted root partition:"
		echo -n $DISK_PASSWD | cryptsetup luksFormat "/dev/$ROOT_DEVNAME" '-'
	fi
	echo $DISK_PASSWD | cryptsetup luksOpen "/dev/$ROOT_DEVNAME" $ROOTFS_NAME

	local fstype=$(lsblk --noheadings --list --output=FSTYPE "/dev/mapper/$ROOTFS_NAME")
	[ "$fstype" == 'ext4' -a "$ROOTENC_REUSE_FS" ] || mkfs.ext4 -F "/dev/mapper/$ROOTFS_NAME"

	[ "$PARTITION_ONLY" ] || {
		mount "/dev/mapper/$ROOTFS_NAME" $TARGET_ROOT

		pu_msg "Copying system to encrypted root partition:"
		_show_output
		rsync $RSYNC_VERBOSITY --archive --exclude=boot $SRC_ROOT/* $TARGET_ROOT
		_hide_output
		sync

		mkdir -p "$TARGET_ROOT/boot"
		touch "$TARGET_ROOT/root/.no_rootfs_resize"

		umount $TARGET_ROOT
	}

	cryptsetup luksClose $ROOTFS_NAME
	do_partprobe

	_add_state_file 'rootpart_copied' 'mount'
}

mount_target() {
	echo $DISK_PASSWD | cryptsetup luksOpen "/dev/$ROOT_DEVNAME" $ROOTFS_NAME
	mount "/dev/mapper/$ROOTFS_NAME" $TARGET_ROOT
	mount "/dev/$BOOT_DEVNAME" "$TARGET_ROOT/boot"

	local src dest args
	while read src dest args; do
		mount $args $src $TARGET_ROOT/$dest
	done <<-EOF
		udev   dev     -t devtmpfs -o rw,relatime,nosuid,mode=0755
		devpts dev/pts -t devpts
		tmpfs  dev/shm -t tmpfs    -o rw,nosuid,nodev,relatime
		proc   proc    -t proc
		sys    sys     -t sysfs
	EOF
}

_copy_to_target() {
	local fn=$1
	if [ -e $fn ]; then
		echo "Copying '$fn'"
		cat $fn > $TARGET_ROOT/$fn
	else
		imsg "Unable to copy '$fn' to target (file does not exist)"
		false
	fi
}

create_etc_crypttab() {
	local root_uuid="$(lsblk --noheadings --list --nodeps --output=UUID /dev/$ROOT_DEVNAME)"
	echo "$ROOTFS_NAME UUID=$root_uuid none initramfs,luks" > "$TARGET_ROOT/etc/crypttab"
	_display_file "$TARGET_ROOT/etc/crypttab"
}

copy_etc_files() {
	_copy_to_target '/etc/resolv.conf'
	_copy_to_target '/etc/hosts'
	set +e
	_copy_to_target /etc/apt/apt.conf.d/*proxy
	set -e
}

_set_target_vars() {
	target_distro=$(chroot $TARGET_ROOT 'lsb_release' '--short' '--codename')
	target_kernel=$(chroot $TARGET_ROOT 'ls' '/boot' | egrep '^vmlinu[xz]')
	imsg "$(printf '%-8s %-28s %s' ''        'Host'       'Target')"
	imsg "$(printf '%-8s %-28s %s' ''        '----'       '------')"
	imsg "$(printf '%-8s %-28s %s' 'distro:' $host_distro $target_distro)"
	imsg "$(printf '%-8s %-28s %s' 'kernel:' $host_kernel $target_kernel)"
}

_distros_match() {
	[ $host_distro == $target_distro ]
}

_kernels_match() {
	[ ${host_kernel%.*} == ${target_kernel%.*} ] || return 1
	[ ${host_kernel##*-} == ${target_kernel##*-} ]
}

copy_etc_files_distro_specific() {
	local files='/etc/apt/sources.list /etc/apt/sources.list.d/armbian.list'
	if _distros_match; then
		for i in $files; do _copy_to_target $i; done
	else
		warn 'Warning: host and target distros do not match:'
		for i in $files; do imsg "  not copying $i"; done
	fi
}

_display_file() {
	local name text reply
	if [ "$2" ]; then
		name="$1"
		text="$2"
	else
		name=${1#$TARGET_ROOT}
		text="$(cat $1)"
	fi
	hl='────────────────────────────────────────'
	hl="$hl$hl$hl"
	hls=${hl:0:${#name}+1}
	echo "┌─$hls─┐"
	echo "│ $name: │"
	echo "├─$hls─┘"
	echo "$text" | sed 's/^/│ /'
}

edit_armbianEnv() {
	local file text
	file="$TARGET_ROOT/boot/armbianEnv.txt"
	ed $file <<-'EOF'
		g/^\s*rootdev=/d
		g/^\s*console=/d
		g/^\s*bootlogo=/d
		wq
	EOF
	text="rootdev=/dev/mapper/$ROOTFS_NAME
console=display
bootlogo=false"
	echo "$text" >> $file
	_display_file $file
}

edit_boot_cmd() {
	local file="$TARGET_ROOT/boot/boot.cmd"
	ed $file <<-'EOF'
		g/^\s*setenv rootdev/d
		g/^\s*setenv console/d
		g/^\s*setenv bootlogo/d
		wq
	EOF
	_display_file $file
}

# Add the following lines to '/etc/initramfs-tools/initramfs.conf'. If
# your board’s IP address will be statically configured, substitute the
# correct static IP address after 'IP='.  If it will be configured via
# DHCP, omit the IP line entirely:
edit_initramfs_conf() {
	local file="$TARGET_ROOT/etc/initramfs-tools/initramfs.conf"
	ed $file <<-'EOF'
		g/^\s*IP=/s/^/# /
		g/^\s*DEVICE=/d
		wq
	EOF
	[ "$IP_ADDRESS" == 'dhcp' -o "$IP_ADDRESS" == 'none' ] || {
		echo "IP=$IP_ADDRESS:::255.255.255.0::eth0:off" >> $file
	}
	[ "$IP_ADDRESS" == 'none' ] || echo "DEVICE=eth0" >> $file
	_display_file $file
}

edit_initramfs_modules() {
	local modlist file hdr
	[ "$ADD_ALL_MODS" ] && {
		if ! _kernels_match; then
			warn 'Host and target kernels do not match.  Not adding modules to initramfs'
		elif ! _distros_match; then
			warn 'Host and target distros do not match.  Not adding modules to initramfs'
		else
			modlist=$(lsmod | cut -d ' ' -f1 | tail -n+2)
		fi
	}
	file="$TARGET_ROOT/etc/initramfs-tools/modules"
	hdr="# List of modules that you want to include in your initramfs.
# They will be loaded at boot time in the order below.
#
# Syntax:  module_name [args ...]
#
# You must run update-initramfs(8) to effect this change.
#
"
	echo "$hdr$modlist" > $file
	_display_file $file
}

copy_authorized_keys() {
	local dest="$TARGET_ROOT/etc/dropbear-initramfs"
	mkdir -p $dest
	/bin/cp 'authorized_keys' $dest
	_display_file "$dest/authorized_keys"
}

create_fstab() {
	local boot_uuid file text
	boot_uuid="$(lsblk --noheadings --list --output=UUID /dev/$BOOT_DEVNAME)"
	file="$TARGET_ROOT/etc/fstab"
	text="/dev/mapper/$ROOTFS_NAME / ext4 defaults,noatime,nodiratime,commit=600,errors=remount-ro 0 1
UUID=$boot_uuid /boot ext4 defaults,noatime,nodiratime,commit=600,errors=remount-ro 0 2
tmpfs /tmp tmpfs defaults,nosuid 0 0"
	echo "$text" > $file
	_display_file $file
}

edit_dropbear_cfg() {
	local dest file text
	dest="$TARGET_ROOT/etc/dropbear-initramfs"
	file="$dest/config"
	text='DROPBEAR_OPTIONS="-p 2222"
DROPBEAR=y'
	if [ "$IP_ADDRESS" == 'none' ]; then
		[ -e $file ] && rm -v $file
		true
	else
		mkdir -p $dest
		[ -e $file ] && grep -q '^DROPBEAR_OPTIONS="-p 2222"' $file || echo "$text" >> $file
		_display_file $file
	fi
}

create_cryptroot_unlock_sh() {
	local dest file text
	dest="$TARGET_ROOT/etc/initramfs-tools/hooks"
	file="$dest/cryptroot-unlock.sh"
	text='#!/bin/sh
if [ "$1" = "prereqs" ]; then echo "dropbear-initramfs"; exit 0; fi
. /usr/share/initramfs-tools/hook-functions
source="/tmp/cryptroot-unlock-profile"
root_home=$(echo $DESTDIR/root-*)
root_home=${root_home#$DESTDIR}
echo "if [ \"\$SSH_CLIENT\" ]; then /usr/bin/cryptroot-unlock; fi" > $source
copy_file ssh_login_profile $source $root_home/.profile
exit 0'
	mkdir -p $dest
	echo "$text" > $file
	chmod 755 $file
	_display_file $file
}

# begin chroot functions:

make_image() {
	local cmd text
	cmd="mkimage -C none -A arm -T script -d /boot/boot.cmd /boot/boot.scr"
	local text=$($cmd)
	_display_file "$cmd" "$text"
}

apt_install_target() {
	local pkgs=$(_print_pkgs_to_install 'target')
	[ "$pkgs" ] && {
		echo "target packages to install: $pkgs"
		local ls1 ls2
		_show_output
		ls1=$(ls -l /boot/initrd.img-*)
# DEBUG:
#		dpkg-reconfigure $pkgs # doesn't work in chroot
#		apt --yes purge $pkgs
#		apt-get --yes --purge autoremove
		dpkg --configure --pending --force-confdef
		set +e
		apt --yes purge 'bash-completion'
		apt --yes purge 'command-not-found'
		set -e
		_apt_update
		echo 'force-confdef' > /root/.dpkg.cfg
		apt --yes install $pkgs
		rm /root/.dpkg.cfg
		apt --yes autoremove
		ls2=$(ls -l /boot/initrd.img-*)
		[ "$ls1" != "$ls2" ] && initramfs_updated='y'
		_hide_output
	}
	true
}

update_initramfs() {
	[ "$ROOTENC_TESTING" ] && return 0
	_show_output
	local ver=$(echo /boot/vmlinu?-* | sed 's/.boot.vmlinu.-//')
	update-initramfs -k $ver -u
	_hide_output
}

check_initramfs() {
	local text chk count
	text="$(lsinitramfs /boot/initrd.img*)"
	set +e

	chk=$(echo "$text" | grep 'cryptsetup')
	count=$(echo "$chk" | wc -l)
	[ "$count" -gt 5 ] || { echo "$text"; die 'Cryptsetup scripts missing in initramfs image'; }
	_display_file "lsinitramfs /boot/initrd.img* | grep 'cryptsetup'" "$chk"

	[ "$IP_ADDRESS" == 'none' ] || {
		chk=$(echo "$text" | grep 'dropbear')
		count=$(echo "$chk" | wc -l)
		[ "$count" -gt 5 ] || { echo "$text"; die 'Dropbear scripts missing in initramfs image'; }
		_display_file "lsinitramfs /boot/initrd.img* | grep 'dropbear'" "$chk"

		chk=$(echo "$text" | grep 'authorized_keys')
		count=$(echo "$chk" | wc -l)
		[ "$count" -eq 1 ] || { echo "$text"; die 'authorized_keys missing in initramfs image'; }
		_display_file "lsinitramfs /boot/initrd.img* | grep 'authorized_keys'" "$chk"
	}
	set -e
}

configure_target() {
	[ "$PARTITION_ONLY" ] && return
	mount_target
	_set_target_vars
	copy_etc_files
	copy_etc_files_distro_specific
	edit_boot_cmd
	edit_initramfs_conf
	edit_initramfs_modules
	[ "$IP_ADDRESS" == 'none' ] || copy_authorized_keys
	create_etc_crypttab
	create_fstab
	edit_dropbear_cfg
	[ "$IP_ADDRESS" == 'none' ] || create_cryptroot_unlock_sh
	edit_armbianEnv
	_debug_pause

	_show_output # this must be done before entering chroot
	/bin/cp $0 $TARGET_ROOT
	export 'ROOTFS_NAME' 'IP_ADDRESS' 'target_distro' 'ROOTENC_TESTING' 'ROOTENC_PAUSE' 'ROOTENC_IGNORE_APT_ERRORS' 'APT_UPGRADE'

	chroot $TARGET_ROOT "./$PROGNAME" $ORIG_OPTS 'in_target'

	/bin/cp -a '/etc/resolv.conf' "$TARGET_ROOT/etc" # this could be a symlink
	/bin/rm "$TARGET_ROOT/$PROGNAME"

	_add_state_file 'target_configured' 'target'
}

_set_env_vars() {
	shopt -s extglob
	local name val
	while [ $# -gt 0 ]; do
		name=${1%=?*} val=${1#+([A-Z_])=}
		[ "$name" == "$1" -o "$val" == "$1" ] && die "$1: illegal argument (must be in format 'NAME=value')"
		eval "$name=$val"
		shift
	done
	shopt -u extglob
}

# begin execution

while getopts hCdmfFpRsuvz OPT
do
		case "$OPT" in
			h)  print_help; exit ;;
			C)  NO_CLEANUP='y' ;;
			F)  FORCE_REBUILD='y' ;;
			f)  FORCE_RECONFIGURE='y' ;;
			m)  ADD_ALL_MODS='y' ;;
			p)  PARTITION_ONLY='y' ;;
			R)  FORCE_REFORMAT_ROOT='y' ;;
			s)  USE_LOCAL_AUTHORIZED_KEYS='y' ;;
			u)  APT_UPGRADE='y' ;;
			d)  DEBUG='y' ;&
			v)  VERBOSE='y' RSYNC_VERBOSITY='--verbose' ;;
			z)  ERASE='y' ;;
			*)  exit ;;
		esac
	ORIG_OPTS+="-$OPT "
done

shift $((OPTIND-1))

trap '_fmsg "$FUNCNAME" $?' RETURN
trap '_sigint_handler' INT
trap '_exit_handler' EXIT

set -o functrace

exec {stdout_dup}>&1
exec {stderr_dup}>&2

[ $UID == 0 -o $EUID == 0 ] || die 'This program must be run as root!'
export HOME='/root'

[ "$DEBUG" ] && set -x

ARG1=$1; shift

_set_env_vars $@

if [ "$ARG1" == 'in_target' ]; then
	SCRIPT_DESC='Target script'
	set -e
	_hide_output
	make_image
	[ "$target_distro" == 'bionic' ] && {
		echo 'export CRYPTSETUP=y' > '/etc/initramfs-tools/conf.d/cryptsetup'
	}
	apt_install_target
	[ "$initramfs_updated" ] || update_initramfs
	check_initramfs
else
	SCRIPT_DESC='Host script'
	_do_header
	_set_host_vars
	get_armbian_image
	apt_install_host # we need cryptsetup in next cmd
	_preclean
	check_sdcard_name_and_params $ARG1
	_get_user_vars
	_test_sdcard_mounted
	_warn_user_opts
	_confirm_user_vars

	set -e
	[ "$IP_ADDRESS" == 'none' ] || get_authorized_keys

	create_build_dir
	[ "$NO_CLEANUP" ] || trap '_clean' EXIT

	setup_loopmount
	_debug_pause

	check_install_state
	_hide_output

	[ "$card_partitioned" == 'n' ]       && _do_partition
	_debug_pause

	[ "$bootpart_copied" == 'n' ]        && copy_system_boot
	[ "$bootpart_label_created" == 'n' ] && create_bootpart_label
	[ "$rootpart_copied" == 'n' ]        && copy_system_root
	[ "$target_configured" == 'n' ]      && configure_target

	sync
	gmsg 'All done!'

	if [ "$IP_ADDRESS" != 'none' ]; then
		imsg "To unlock the target disk, execute the following from the unlocking host:"
		imsg "    ssh -p 2222 root@${IP_ADDRESS/dhcp/TARGET_IP}"
	fi
fi