#!/bin/bash
# SPDX-License-Identifier: MIT
#
# Copyright IBM Corp.


#
# CLEANUP STACK FUNCTIONS
#

# Initialize the cleanup stack as an array
declare -a CLEANUP_STACK=()

cleanup_push() {
	local cmd="$*"
	if [[ -z "$cmd" ]]; then
		log_error "pvics: no command provided"
		return 1
	fi
	CLEANUP_STACK+=("$cmd")
	log_debug "registered cleanup: ${cmd}"
	return 0
}

cleanup_pop() {
	local stack_size=${#CLEANUP_STACK[@]}

	if [[ $stack_size -eq 0 ]]; then
		log_warn "cleanup_pop: Warning - cleanup stack is empty"
		return 1
	fi

	# Get the last command (top of stack)
	local last_idx=$((stack_size - 1))
	local cmd="${CLEANUP_STACK[$last_idx]}"

	# Remove it from the stack
	unset 'CLEANUP_STACK[$last_idx]'

	# Execute the command
	log_debug "cleanup_pop: Executing: $cmd"
	execute "${cmd}"
	local ret=$?

	if [[ $ret -ne 0 ]]; then
		log_warn "cleanup_pop: Warning - command failed with exit code $ret"
	fi

	return $ret
}

cleanup_run() {
	local stack_size=${#CLEANUP_STACK[@]}
	local failed=0

	if [[ "${stack_size}" -eq 0 ]]; then
		log_debug "cleanup_run: No cleanup commands to execute"
		return 0
	fi

	log_debug "cleanup_run: Executing ${stack_size} cleanup command(s)"

	# Execute commands in reverse order (LIFO)
	while [[ ${#CLEANUP_STACK[@]} -gt 0 ]]; do
		if ! cleanup_pop; then
		((failed++))
		fi
	done

	if [[ "${failed}" -gt 0 ]]; then
		log_warn "cleanup_run: Warning - ${failed} command(s) failed"
		return 1
	fi

	return 0
}

cleanup_clear() {
	local stack_size=${#CLEANUP_STACK[@]}
	CLEANUP_STACK=()
	log_debug "cleanup_clear: Cleared $stack_size command(s) from stack"
	return 0
}

cleanup_show() {
	local stack_size=${#CLEANUP_STACK[@]}

	if [[ $stack_size -eq 0 ]]; then
		log_info "Cleanup stack is empty"
		return 0
	fi

	log_info "Cleanup stack ($stack_size command(s)):"
	local idx=0
	for cmd in "${CLEANUP_STACK[@]}"; do
		log_info "  [$idx] $cmd"
		((idx++))
	done

	return 0
}

cleanup() {
	local rc=${1:-1}
	local stack_size=${#CLEANUP_STACK[@]}

	trap - ERR EXIT PIPE

	if [[ "${stack_size}" -gt 0 ]]; then
		cleanup_run
		log_info "Cleanup finished"
	fi

	if [[ "${rc}" -ne 0 ]]; then
		exit "${rc}"
	fi

	return 0
}


#
# LOGGING FUNCTIONS
#

# Configuration for logger utility
LOGGER_TAG="pvics"
LOGGER_FACILITY="user"

log_init() {
	logger -t "${LOGGER_TAG}" -p "${LOGGER_FACILITY}.info" "Logging initialized"
	return 0
}

log_debug() {
	local msg="$*"
	logger -t "${LOGGER_TAG}" -p "${LOGGER_FACILITY}.debug" "${msg}"
	return 0
}

log_info() {
	local msg="$*"
	echo "[ INFO ] ${msg}"
	logger -t "${LOGGER_TAG}" -p "${LOGGER_FACILITY}.info" "${msg}"
	return 0
}

log_warn() {
	local msg="$*"
	echo "[ WARN ] ${msg}"
	logger -t "${LOGGER_TAG}" -p "${LOGGER_FACILITY}.warning" "${msg}"
	return 0
}

log_error() {
	local msg="$*"
	echo "[ ERR  ] ${msg}" >&2
	logger -t "${LOGGER_TAG}" -p "${LOGGER_FACILITY}.err" "${msg}"
	return 1
}

log_cleanup() {
	logger -t "${LOGGER_TAG}" -p "${LOGGER_FACILITY}.info" "Logging cleanup complete"
	return 0
}

setup_logger() {
	log_init
	cleanup_push log_cleanup
	return 0
}

warn_overwrite() {
	local file

	if [[ $# -lt 1 ]]; then
		log_error "internal error"
	fi

	file=$1

	if [[ -e "${file}" ]]; then
		log_warn "${file} already exists and may be overwritten"
	fi

	return 0
}

err_noexist() {
	local file

	if [[ $# -lt 1 ]]; then
		return 0
	fi

	file=$1

	if [[ ! -e "${file}" ]]; then
		log_error "${file} does not exist"
	fi

	return 0
}


#
# PREREQ FUNCTIONS
#

check_pvsecret_ebc() {
	local pvsecret_version

	# Run pvsecret with --version --verbose to check for EBC support
	pvsecret_version=$(pvsecret --version --verbose 2>&1 || true)

	if ! echo "${pvsecret_version}" | grep -q "+ebc"; then
		log_error "pvsecret does not support EBC feature. Please use a version compiled with EBC support."
	fi

	log_info "pvsecret supports EBC feature"

	return 0
}

check_prereqs_convert() {
	local tools

	tools=(
		"blkid"
		"lsblk"
		"lsinitrd"
		"modprobe"
		"mount"
		"mountpoint"
		"pvextract-hdr"
		"pvimg"
		"printf"
		"qemu-nbd"
		"systemctl"
		"umount"
	)

	for tool in "${tools[@]}"; do
		require_command "${tool}"
	done

	# Check for virtualization tools based on architecture
	if [[ "${ARCH}" == "s390x" ]]; then
		require_command "virt-install"
		require_command "virsh"
	else
		require_command "qemu-system-s390x"
		require_command "pgrep"
	fi

	return 0
}

check_prereqs_encrypt() {
	local tools

	tools=(
		"blkid"
		"cryptsetup"
		"hexdump"
		"lsblk"
		"mktemp"
		"modprobe"
		"mount"
		"mountpoint"
		"pvebc"
		"pvextract-hdr"
		"pvsecret"
		"qemu-img"
		"qemu-nbd"
		"sha256sum"
		"strings"
		"umount"
		"xxd"
		"virt-resize"
	)

	for tool in "${tools[@]}"; do
		require_command "${tool}"
	done

	# Check if pvsecret supports EBC feature
	check_pvsecret_ebc

	return 0
}

check_prereqs_list() {
	local tools

	tools=(
		"blkid"
		"lsblk"
		"lsinitrd"
		"modprobe"
		"mountpoint"
		"mount"
		"qemu-nbd"
		"sha256sum"
		"umount"
	)

	for tool in "${tools[@]}"; do
		require_command "${tool}"
	done

	return 0
}

check_prereqs() {
	local tools
	log_info "checking for required commands"

	# always needed prereqs
	tools=(
		"grep"
		"mkdir"
		"uname"
		"uuidgen"
		"yq"
	)
	for tool in "${tools[@]}"; do
		require_command "${tool}"
	done

	if [[ "${ACTION}" == "convert" ]]; then
		check_prereqs_convert
	elif [[ "${ACTION}" == "encrypt" ]]; then
		check_prereqs_encrypt
	elif [[ "${ACTION}" == "full" ]]; then
		check_prereqs_convert
		check_prereqs_encrypt
	elif [[ "${ACTION}" == "list" ]]; then
		check_prereqs_list
	else
		log_error "internal error"
	fi

	log_info "all required commands found, continuing..."

	return 0
}

require_command() {
	local cmd

	cmd="$1"

	command -v "${cmd}" >/dev/null 2>&1 || \
		log_error "${cmd} required but not installed."

	return 0
}


#
# HELPER FUNCTIONS
#

get_free_nbd() {
	local free

	test -b /dev/nbd0 || modprobe nbd

	free=$(lsblk --output NAME,SIZE \
		| grep nbd \
		| grep 0B \
		| grep -oE "nbd[0-9]+" \
		| head -n 1)

	if [[ -z "${free}" ]]; then
		log_error "no free NBD found"
	fi

	free="/dev/${free}"

	log_info "found free NBD: ${free}"

	NBD="${free}"

	return 0
}

execute() {
	log_debug "$@"
	# shellcheck disable=SC2294
	eval "$@"

	return $?
}

get_arch() {
	ARCH=$(uname -m)
	if [[ "${ARCH}" == "" ]]; then
		log_error "Architecture not officially supported"
		return 1
	else
		if [[ "${ARCH}" != "s390x" && "${ARCH}" != "x86_64" ]]; then
			log_warn "the detected host architecture ${ARCH} is not one of the officially supported architectures (s390x, x86_64)"
		else
			log_info "found supported architecture ${ARCH}"
		fi
	fi

	return 0
}


# $1 path to image
# Returns: Sets global NBD variable
connect_nbd() {
	local image i nbd_size

	if [[ $# -lt 1 ]]; then
		log_error "internal error"
	fi

	image="$1"

	get_free_nbd

	execute qemu-nbd --connect="${NBD}" "${image}"

	log_info "waiting for qemu-nbd:"
	for i in {1..10}; do
		test -b "${NBD}p1" && break
		echo -n "."
		sleep 0.1
	done
	echo ""

	if [[ -b "${NBD}p1" ]]; then
		# Verify the NBD device is actually connected to our image
		nbd_size=$(lsblk --bytes --noheadings --output SIZE "${NBD}" 2>/dev/null || echo "0")
		if [[ "${nbd_size}" == "0" ]]; then
			log_error "NBD device ${NBD} appears to be claimed by another process"
		fi
		cleanup_push disconnect_nbd
	else
		log_error "unable to connect ${image} to ${NBD}"
	fi

	return 0
}

disconnect_nbd() {
	test -z "${NBD}" && return 0

	execute "qemu-nbd --disconnect '${NBD}' 2>/dev/null"
	unset NBD

	return 0
}

# $1 partition device (e.g., "${NBD}p${BOOT_PARTNUM}")
# $2 mount point path
# $3 optional: mount options (e.g., "-r" for read-only)
mount_partition() {
	local partition mount_point mount_opts

	if [[ $# -lt 2 ]]; then
		log_error "internal error"
	fi

	partition="$1"
	mount_point="$2"
	mount_opts="${3:-}"

	execute mount "${mount_opts}" "${partition}" "${mount_point}"

	if mountpoint -q "${mount_point}"; then
		cleanup_push umount_partition "${mount_point}"
	fi

	return 0
}

# $1 mountpoint
umount_partition() {
	local mntp="${1:?no mountpoint specified}"

	if mountpoint -q "${mntp}"; then
		umount "${mntp}"
	fi

	return 0
}


# $1 path to asr
# $2 path to toc.pol
add_asr_to_toc() {
	local toc asr

	if [[ $# -lt 2 ]]; then
		log_error "internal error"
	fi

	asr="$1"
	toc="$2"

	log_info "adding Add-Secret-Request ${asr} to TOC policy ${toc}"

	xxd -p -s -16 "${asr}" >> "${toc}"

	return 0
}

# $1 partition label
# $2 path to image
get_partnum() {
	local partition image p partnum

	if [[ $# -lt 2 ]]; then
		log_error "internal error"
	fi

	partition="$1"
	image="$2"

	connect_nbd "${image}"

	# get partitions
	for p in "${NBD}"p*; do

		if [[ $(blkid | grep -E "^${p}" | grep -oE "LABEL=\"[a-zA-Z]*\"" | cut -d '"' -f 2) == "${partition}" ]]; then
			partnum="$(blkid | grep -oE "^${p}" | cut -d 'p' -f 2)"
			log_info "Found partition with label ${partition} at partition ${partnum}"

			cleanup_pop  # Disconnect and remove from stack
			PARTNUM="${partnum}"
			return 0
		fi
	done

	cleanup_pop  # Disconnect and remove from stack
	PARTNUM=""

	return 0
}

# Build pv_cmd array for pvimg/pvsecret commands
# $1: hkds - space-separated list of HKD paths
# $2: no_verify - "true" or "false"
# $3: certs - space-separated list of certificate paths (optional if no_verify=true)
# $4: crls - space-separated list of CRL paths (optional if no_verify=true)
# $5: rootca - path to root CA (optional if no_verify=true)
# $6: offline - "true" or "false" (optional if no_verify=true)
# Returns: Sets global pv_cmd array
build_pv_cmd() {
	local hkds no_verify certs crls rootca offline
	local h c files f

	if [[ $# -lt 2 ]]; then
		log_error "internal error: build_pv_cmd requires at least 2 arguments"
	fi

	hkds="$1"
	no_verify="$2"
	certs="${3:-}"
	crls="${4:-}"
	rootca="${5:-}"
	offline="${6:-false}"

	# Initialize pv_cmd array
	pv_cmd=()

	# Add HKD files
	for h in ${hkds}; do
		files=$(ls "${h}")
		for f in ${files}; do
			pv_cmd+=("--host-key-document" "${f}")
		done
	done

	# If verification is enabled
	if [[ "${no_verify}" == "false" ]]; then
		# Add certificates
		for c in ${certs}; do
			files=$(ls "${c}")
			for f in ${files}; do
				pv_cmd+=("--cert" "${f}")
			done
		done

		# Add CRLs
		for c in ${crls}; do
			files=$(ls "${c}")
			for f in ${files}; do
				pv_cmd+=("--crl" "${f}")
			done
		done

		# Add root CA
		pv_cmd+=("--root-ca" "${rootca}")

		# Add offline flag if requested
		if [[ "${offline}" == "true" ]]; then
			pv_cmd+=("--offline")
		fi
	else
		# Verification disabled
		pv_cmd+=("--no-verify")
	fi

	return 0
}

# $1 kernel
# $2 initramfs
# $3 kernel parameter
# $4 output
# $5 yaml configuration
#
# If this function is called by another script that sourced this one the yaml configuration has to
# be supplied as many variables will not be set otherwise
build_sel_image() {
	if [[ $# -lt 4 ]]; then
		return 1
	fi

	i="$1"
	r="$2"
	p="$3"
	o="$4"
	err_noexist "${i}"
	err_noexist "${r}"
	err_noexist "${p}"

	if [[ $# -gt 4 ]]; then
		CONFIG_FILE="$5"
		err_noexist "${CONFIG_FILE}"
		parse_yaml_pv
	fi

	log_info "The following configuration is used to generate the SEL image:"
	log_info "kernel:		${i}"
	log_info "initramfs:		${r}"
	log_info "kernel parameter:	$(cat "${p}")"

	# Build pv_cmd array using helper function
	build_pv_cmd "${hkds}" "${NO_VERIFY}" "${certs}" "${crls}" "${rootca}" "${offline}"

	# create SEL image
	pvimg_cmd=("pvimg" "create")
	pvimg_cmd+=("--kernel" "${i}")
	pvimg_cmd+=("--ramdisk" "${r}")
	pvimg_cmd+=("--parmfile" "${p}")
	pvimg_cmd+=("--output" "${o}")
	pvimg_cmd+=("${pv_cmd[@]}")
	if [[ "${NO_EBC:-false}" != "true" ]]; then
		pvimg_cmd+=("--enable-cck-update" "--quiet" "--disable-image-encryption")
	fi
	pvimg_cmd+=("${PVIMG_USER_OPTS}")

	execute "${pvimg_cmd[@]}"

	return 0
}


#
# USAGE FUNCTIONS
#

usage() {
	local action required_options

	action="${ACTION}"
	required_options="--image <FILE>"

	if [[ "${action}" == "list" ]]; then
		echo "
List all available boot loader entries of a s390x guest image and its partitions."
	elif [[ "${action}" == "convert" ]]; then
		echo "
Convert a s390x guest to a Secure Execution for Linux guest."
	elif [[ "${action}" == "encrypt" ]]; then
		echo "
Encrypt the root filesystem of a s390x Secure Execution for Linux guest."
	elif [[ "${action}" == "" || "${action}" == "full" ]]; then
		if [[ "${action}" == "" ]]; then
			action="[ACTION]"
		fi
		echo "
Convert a s390x guest to a Secure Execution for Linux guest with encrypted root
filesystem."
	fi

	if [[ "${action}" == "convert" || "${action}" == "encrypt" || "${action}" == "full" ]]; then
		required_options="${required_options} --config <FILE>"
	fi

	echo "
Usage: $0 ${action} [OPTIONS] ${required_options}"

	if [[ "${action}" == "[ACTION]" ]]; then
		echo "
Actions:
	list		List boot entries of a guest
	convert		Convert the guest to Secure Execution for Linux guest
	encrypt		Encrypt the root filesystem of the guest
	full		Convert the guest to SEL guest and encrypt the root fs"
	fi

	echo "
Options:
	-h, --help		Show this help text
	    --version		Show version information"
	if [[ "${action}" == "[ACTION]" ]]; then
		echo -e "\t-c, --config\t\tConfiguration yaml file"
	fi

	echo ""

	return 0
}

print_version() {
	cat <<-EOD
	$0: version %S390_TOOLS_VERSION%
	Copyright IBM Corp.
	EOD
}


#
# CLI FUNCTIONS
#

cli() {
	local temp

	if [[ "$#" -lt 1 ]]; then
		usage
		return 1
	fi

	if [[ "$1" == "convert" ]]; then
		ACTION="convert"
		shift
	elif [[ "$1" == "encrypt" ]]; then
		ACTION="encrypt"
		shift
	elif [[ "$1" == "full" ]]; then
		ACTION="full"
		shift
	elif [[ "$1" == "list" ]]; then
		ACTION="list"
		shift
	fi

	temp=$(getopt -o 'hc:i:' --long 'help,version,config:,image:' -- "$@")
	if ! eval set -- "$temp"; then
		usage
		return 1
	fi

	eval set -- "$temp"
	unset temp

	while true; do
		case "$1" in
			'-h'|'--help')
				usage
				exit 0
			;;
			'--version')
				print_version
				exit 0
			;;
			'-c'|'--config')
				case "$2" in
				'')
					usage
					exit 1
				;;
				*)
					CONFIG_FILE="$2"
				;;
				esac
				shift 2
				continue
			;;
			'-i'|'--image')
				case "$2" in
				'')
					usage
					exit 1
				;;
				*)
					IMAGE="$2"
				;;
				esac
				shift 2
				continue
			;;
			'--')
				shift
				break
			;;
			*)
				usage
				exit 1
			;;
		esac
	done

	if [[ -z ${IMAGE} ]]; then
		usage
		exit 1
	elif [[ ! -f ${IMAGE} ]]; then
		log_error "base image ${IMAGE} does not exist"

		return 1
	fi

	if [[ -z ${CONFIG_FILE} && ${ACTION} != "list" ]]; then
		usage
		exit 1
	elif [[ -n ${CONFIG_FILE} && ! -f ${CONFIG_FILE} ]]; then
		log_error "config file ${CONFIG_FILE} does not exist"

		return 1
	fi

	if [[ ${ACTION} != "convert" && ${ACTION} != "encrypt" && ${ACTION} != "full" && ${ACTION} != "list" ]]; then
		usage
		exit 1
	fi

	return 0
}


#
# YAML FUNCTIONS
#

parse_yaml_pv() {
	local files f hkd cert crl

	NO_VERIFY=$(yaml_get_opt ".no-verify")
	if [[ "${NO_VERIFY}" == "unset" ]]; then
		NO_VERIFY=false
	fi

	PVIMG_USER_OPTS="$(yaml_get_opt ".convert.pvimg-create-options")"
	if [[ "${PVIMG_USER_OPTS}" == "unset" && "${NO_EBC}" != "true" ]]; then
		PVIMG_USER_OPTS="--enable-pckmo-hmac"
	elif [[ "${PVIMG_USER_OPTS}" == "unset" ]]; then
		PVIMG_USER_OPTS=""
	fi

	HKDs="$(yaml_get_req ".hkds[]")"
	for hkd in ${HKDs}; do
		files=$(ls "${hkd}")
		for f in ${files}; do
			err_noexist "${f}"
		done
	done

	if [[ "${NO_VERIFY}" == "false" ]]; then
		CC_CERTS="$(yaml_get_req ".certificate-chain.certs[]")"
		for cert in ${CC_CERTS}; do
			files=$(ls "${cert}")
			for f in ${files}; do
				err_noexist "${f}"
			done
		done
		CC_CRLS="$(yaml_get_req ".certificate-chain.crls[]")"
		for crl in ${CC_CRLS}; do
			files=$(ls "${crl}")
			for f in ${files}; do
				err_noexist "${f}"
			done
		done
		CC_ROOTCA=$(yaml_get_req ".certificate-chain.root-ca")
		err_noexist "${CC_ROOTCA}"

		CC_OFFLINE=$(yaml_get_opt ".certificate-chain.offline")
		if [[ "${CC_OFFLINE}" == "unset" ]]; then
			CC_OFFLINE="false"
		fi
	fi

	return 0
}

parse_yaml() {
	# general required configuration settings
	NO_EBC=$(yaml_get_opt ".no-ebc")
	if [[ ${NO_EBC} == "unset" ]]; then
		NO_EBC=false
	fi

	parse_yaml_pv

	OUT=$(yaml_get_req ".out")
	err_noexist "${OUT}"

	if [[ ${ACTION} == "convert" || ${ACTION} == "full" ]]; then
		C_BOOT_LOADER_ENTRY=$(yaml_get_req ".convert.boot-loader-entry")
		C_SEL_KERNEL_PARAMETER=$(yaml_get_opt ".convert.sel-kernel-parameter")
	fi

	if [[ ${ACTION} == "encrypt" || ${ACTION} == "full" ]]; then
		E_CCK=$(yaml_get_opt ".encrypt.cck")
		if [[ ${E_CCK} != "unset" ]]; then
			err_noexist "${E_CCK}"
		fi
		E_LUKS_RFS_KEY=$(yaml_get_opt ".encrypt.luks-key")
		if [[ ${E_LUKS_RFS_KEY} != "unset" ]]; then
			err_noexist "${E_LUKS_RFS_KEY}"
		fi
		E_LUKS_PASSPHRASE=$(yaml_get_opt ".encrypt.luks-passphrase")
		if [[ ${E_LUKS_PASSPHRASE} != "unset" ]]; then
			err_noexist "${E_LUKS_PASSPHRASE}"
		fi
		E_LUKS_RFS_KEY_ASR_NAME=$(yaml_get_opt ".encrypt.luks-key-asr-name")
		E_LUKS_KEY_SIZE=$(yaml_get_opt ".encrypt.luks-key-size")
		if [[ "${E_LUKS_KEY_SIZE}" == "unset" ]]; then
			E_LUKS_KEY_SIZE="512"
		elif [[ "${E_LUKS_KEY_SIZE}" != "256" && "${E_LUKS_KEY_SIZE}" != "512" ]]; then
			log_error "invalid .encrypt.luks-key-size of ${E_LUKS_KEY_SIZE} != 256 or 512"
		fi
		E_ADD_SECRET_REQUESTS="$(yaml_get_opt ".encrypt.add-secret-requests[]")"
		if [[ "${E_ADD_SECRET_REQUESTS}" != "unset" ]]; then
			for asr in ${E_ADD_SECRET_REQUESTS}; do
				files=$(ls "${asr}")
				for f in ${files}; do
					err_noexist "${f}"
				done
			done

			# extension secret is now required
			E_EXTENSION_SECRET=$(yaml_get_req ".encrypt.extension-secret")
			err_noexist "${E_EXTENSION_SECRET}"
		else
			E_EXTENSION_SECRET=$(yaml_get_opt ".encrypt.extension-secret")
			if [[ ${E_EXTENSION_SECRET} != "unset" ]]; then
				err_noexist "${E_EXTENSION_SECRET}"
			fi
		fi
	fi

	return 0
}

yaml_get_req() {
	yaml_get "$@" true

	return 0
}

yaml_get_opt() {
	yaml_get "$@" false

	return 0
}

yaml_get() {
	local key required ret

	if [[ $# -lt 2 ]]; then
		log_error "internal error"
	fi

	key="$1"
	required="$2"

	ret="$(yq e -r "${key} // \"unset\"" "${CONFIG_FILE}")"

	if [[ "${required}" == "true" && "${ret}" == "unset" ]]; then
		log_error "key ${key} not specified in ${CONFIG_FILE} but required"
	fi

	echo "${ret}"

	return 0
}


#
# ACTION FUNCTIONS
#

list() {
	local image temp_boot ble_dir f title kernel initramfs kernel_params valid

	image="${IMAGE}"

	# mount guest
	connect_nbd "${image}"

	temp_boot="${TEMP_DIR}/boot"
	mount_partition "${NBD}p${BOOT_PARTNUM}" "${temp_boot}" "-r"

	ble_dir="${temp_boot}/loader/entries"
	if [[ ! -d "${ble_dir}" ]]; then
		log_error "directory ${ble_dir} does not exist, unable to find boot loader entries"
	fi

	log_info "Found the following boot loader entries:"
	for f in "${ble_dir}"/*.conf; do

		title="$(grep -E "^title" "${f}" | grep -oE " .*" | grep -oE "[^ ]*")"
		kernel="$(grep -E "^linux" "${f}" | cut -d ' ' -f 2)"
		initramfs="$(grep -E "^initrd" "${f}" | cut -d ' ' -f 2)"
		kernel_params="$(grep -E "^options" "${f}" | cut -d ' ' -f 2-)"

		if echo "${kernel_params}" | grep -q "root=LABEL=root"; then
			valid="valid"
		elif echo "${kernel_params}" | grep -q "root=/dev/disk/by-label/root"; then
			valid="valid"
		else
			valid="invalid"
		fi

		if ! lsinitrd "${TEMP_DIR}${initramfs}" | grep -q "sel-ebc.target"; then
			valid="invalid"
		fi

		echo "
title: \"${title}\" [ ${valid} ]:
	kernel:		${kernel}
		SHA256 ($(sha256sum "${TEMP_DIR}${kernel}" | cut -d ' ' -f 1))
	initramfs:	${initramfs}
		SHA256 ($(sha256sum "${TEMP_DIR}${initramfs}" | cut -d ' ' -f 1))
	kernel_params:	${kernel_params}
"
	done

	cleanup_pop  # Unmount temp_boot
	cleanup_pop  # Disconnect NBD

	return 0
}

# Generate SEL guest from existing guest
convert() {
	# setup variables
	local rootca offline crls certs hkds kernel_parameter
	local kernel_parameter_file sel_kernel_parameter initramfs kernel dest
	local image temp_boot temp_root sel_header guest_name
	local pvimg_cmd pv_cmd ble_array b

	# initialize
	image=${IMAGE}
	ble=${C_BOOT_LOADER_ENTRY}
	kernel_parameter_file="${TEMP_DIR}/kernel_parameter"
	hkds=${HKDs}
	# optional
	sel_kernel_parameter=${C_SEL_KERNEL_PARAMETER}
	certs="${CC_CERTS}"
	crls="${CC_CRLS}"
	rootca="${CC_ROOTCA}"
	offline="${CC_OFFLINE}"

	# check for files
	err_noexist "${image}"

	if [[ ${sel_kernel_parameter} == "unset" ]]; then
		sel_kernel_parameter=""
	fi

	# create copy for safety
	log_info "copying image; depending on size this may take some time"
	execute cp "${image}" "${TEMP_DIR}/image.copy"
	image="${TEMP_DIR}/image.copy"

	# mount guest
	connect_nbd "${image}"
	temp_boot="${TEMP_DIR}/boot"
	temp_root="${TEMP_DIR}/root"
	mount_partition "${NBD}p${BOOT_PARTNUM}" "${temp_boot}"
	mount_partition "${NBD}p${ROOT_PARTNUM}" "${temp_root}"

	# get kernel, initramfs, and kernel parameter from boot loader entry
	for f in "${temp_boot}"/loader/entries/*.conf; do

		title="$(grep -E "^title" "${f}" | cut -d ' ' -f 3)"
		if [[ "${title}" != "${ble}" ]]; then
			continue
		fi

		kernel="$(grep -E "^linux" "${f}" | cut -d ' ' -f 2)"
		initramfs="$(grep -E "^initrd" "${f}" | cut -d ' ' -f 2)"
		if [[ "${NO_EBC}" != "true" ]]; then
			kernel_parameter="rd.sel-ebc "
		fi
		kernel_parameter+="$(grep -E "^options" "${f}" | cut -d ' ' -f 2-) ${sel_kernel_parameter}"
		break
	done
	if [[ "${NO_EBC}" != "true" ]]; then
		if [[ $(echo "${kernel_parameter}" | grep "root=LABEL=root") == "" \
			&& $? == "1" \
			&& $(echo "${kernel_parameter}" | grep "root=/dev/disk/by-label/root") == "" \
			&& $? == "1" ]]; then
			log_error "root partition has to be identified using the LABEL root in the kernel parameter line"
		fi
		if [[ $(lsinitrd "${TEMP_DIR}${initramfs}" | grep "/usr/lib/systemd/system/sel-ebc.target") == "" \
			&& $? == "1" ]]; then
			log_error "initramfs ${initramfs} does not contain IBMs SEL EBC dracut module from s390-tools"
		fi
	fi

	# check existence
	echo "${kernel_parameter}" > "${kernel_parameter_file}"

	build_sel_image "${TEMP_DIR}${kernel}" "${TEMP_DIR}${initramfs}" "${kernel_parameter_file}" "${temp_boot}/sel-ebc.img"

	# extract header from SEL image
	sel_header="${OUT}/selhdr.bin"
	execute pvextract-hdr -o "${sel_header}" "${temp_boot}/sel-ebc.img"

	# make old boot loader entries invalid (zipl will only find files ending in .conf)
	mapfile -t ble_array < <(ls "${temp_boot}/loader/entries/")
	for b in "${ble_array[@]}"; do
		execute mv "${temp_boot}/loader/entries/${b}" "${temp_boot}/loader/entries/${b}.old"
	done

	# create boot entry for SEL
	printf 'title sel-ebc\nlinux /boot/sel-ebc.img\n' > "${temp_boot}/loader/entries/sel-ebc.conf"

	# inject systemd service to run zipl
		local service_name="ebczipl.service"
		local systemd_dir="/usr/lib/systemd/system"
		local link
		cat > "${temp_root}${systemd_dir}/${service_name}" << EOF
[Unit]
Description=call zipl and shutdown system

[Service]
Type=oneshot
ExecStart=zipl
ExecStartPost=shutdown now
RemainAfterExit=yes
StandardOutput=file:/var/log/sel-ebc-zipl.log
StandardError=file:/var/log/sel-ebc-zipl.log

[Install]
WantedBy=multi-user.target
EOF
		systemctl --root="${temp_root}" --no-reload enable "${service_name}"

		# unmount mounted image
		cleanup_pop  # Unmount temp_root
		cleanup_pop  # Unmount temp_boot
		cleanup_pop  # Disconnect NBD

		guest_name="sel-ebc-${UUID}"

		# start guest
		log_info "starting guest to run zipl"
		if [[ "${ARCH}" == "s390x" ]]; then
			execute virt-install \
				--name "${guest_name}" \
				--memory 2048 \
				--vcpus 2 \
				--disk path="${image}",format=qcow2 \
				--import \
				--network network=default,model=virtio \
				--graphics none \
				--console pty,target_type=serial \
				--noautoconsole \
				--cpu model=host-model,-deflate \
				--osinfo detect=on,require=off > /dev/null
		else
			execute qemu-system-s390x \
				-name "${guest_name}" \
				-machine s390-ccw-virtio \
				-cpu max \
				-m 2048 \
				-drive file="${image}",if=virtio,format=qcow2 \
				-serial none \
				-display none \
				-daemonize \
				-netdev user,id=net0 \
				-device virtio-net-ccw,netdev=net0
		fi

		# shutdown and remove guest
		if [[ "${ARCH}" == "s390x" ]]; then
			log_info "waiting for ${guest_name} to shut down:"
			for _ in {1..200}; do
				execute virsh list --all | grep "${guest_name}" | grep "shut off" > /dev/null && break
				echo -n "."
				sleep 0.2
			done
			echo ""

			execute virsh undefine "${guest_name}"
		else
			log_info "waiting for ${guest_name} to shut down:"
			for _ in {1..200}; do
				execute ! pgrep -af "qemu-system-s390x.*${guest_name}" >/dev/null && break
				echo -n "."
				sleep 2
			done
			echo ""
		fi

		# mount guest
		connect_nbd "${image}"
		temp_root="${TEMP_DIR}/root"
		mount_partition "${NBD}p${ROOT_PARTNUM}" "${temp_root}"

		# eject systemd service to run zipl
		if [[ -f "${temp_root}${systemd_dir}/${service_name}" ]]; then
			rm -f "${temp_root}${systemd_dir}/${service_name}"
		fi
		link="${temp_root}${systemd_dir}/multi-user.target.wants/${service_name}"
		if [[ -h "${link}" ]]; then
			rm -f "${link}"
		fi

	# unmount mounted image
	cleanup_pop  # Unmount temp_root
	cleanup_pop  # Disconnect NBD

	# copy image to output directory
	IMAGE="${OUT}/image.qcow2"
	execute mv "${image}" "${IMAGE}"

	return 0
}

# Encrypt root partition of SEL guest
encrypt() {
	local image dest luks_dev_name passphrase luks_segment_key_size segment_key
	local asr_name hkds cck asrs certs crls rootca offline extension_secret
	local pvsecret_cmd_static pvsecret_cmd pv_cmd
	local retr_sec_type luks_segment_key_bytes blob blob_file
	local sector_size metadata_size keyslots_size temp_boot sics header
	local image_resized root_part retr_sec_id dump key_size pv_out pv_in
	local kcmdline files f asr

	image="${IMAGE}"
	dest="${OUT}/image.qcow2"
	luks_dev_name="cryptroot"
	passphrase="${E_LUKS_PASSPHRASE}"
	luks_segment_key_size="${E_LUKS_KEY_SIZE}"
	segment_key="${E_LUKS_RFS_KEY}"
	asr_name="${E_LUKS_RFS_KEY_ASR_NAME}"
	hkds="${HKDs}"
	cck="${E_CCK}"
	asrs="${E_ADD_SECRET_REQUESTS}"
	certs="${CC_CERTS}"
	crls="${CC_CRLS}"
	rootca="${CC_ROOTCA}"
	offline="${CC_OFFLINE}"
	extension_secret="${E_EXTENSION_SECRET}"
	pvsecret_cmd_static="pvsecret create "

	if [[ "${NO_EBC}" == "true" ]]; then
		log_info "EBC disabled, skipping encrypt"
		return 0
	fi

	# set default LUKS key ASR name
	if [[ "${asr_name}" == "unset" ]]; then
		asr_name="rfs-luks-key"
	fi

	# generate random extension secret if none supplied
	if [[ "${extension_secret}" == "unset" ]]; then
		extension_secret="${OUT}/extension.secret"
		execute dd if=/dev/random of="${extension_secret}" bs=32 count=1
		log_info "generated new extension secret to ${extension_secret}"
	fi

	# generate random cck if none supplied
	if [[ "${cck}" == "unset" ]]; then
		cck="${OUT}/cck.key"
		execute dd if=/dev/random of="${cck}" bs=32 count=1
		log_info "generated new Customer-Communication-Key to ${cck}"
	fi

	# generate random luks passphrase if none supplied
	if [[ "${passphrase}" == "unset" ]]; then
		passphrase="${OUT}/passphrase"
		execute dd if=/dev/random of="${passphrase}" bs=32 count=1
		log_info "generated new LUKS passphrase to ${passphrase}"
	fi

	# check or set default LUKS key size
	if [[ "${luks_segment_key_size}" == "unset" ]]; then
		if [[ "${segment_key}" == "unset" ]]; then
			luks_segment_key_size="512"
		else
			key_size="$(wc --bytes < "${segment_key}")"
			if [[ "${key_size}" -lt "256" ]]; then
				log_error "${segment_key} has to be at least 32 bytes"
			elif [[ "${key_size}" -lt "512" ]]; then
				luks_segment_key_size="256"
			else
				luks_segment_key_size="256"
			fi
		fi
	fi

	# set retrievable secret type
	if [[ "${luks_segment_key_size}" == "256" ]]; then
		retr_sec_type="7"
	elif [[ "${luks_segment_key_size}" == "512" ]]; then
		retr_sec_type="8"
	else
		log_error "Cipher aes-xts-plain64 requires a key size of 256 or 512 bit!"
	fi

	# generate random LUKS key if none supplied
	if [[ "${segment_key}" == "unset" ]]; then
		luks_segment_key_bytes=$((luks_segment_key_size / 8))

		segment_key="${OUT}/rfs.key"
		execute dd if=/dev/random of="${segment_key}" bs="${luks_segment_key_bytes}" count=1
		log_info "generated new LUKS key for root filesystem to ${segment_key}"
	fi

	# Increase QCOW2 disk size by 32MiB to allow additional space for LUKS2 header
	log_info "increase size of qcow2 to fit the LUKS header"
	execute qemu-img resize "${image}" +32M
	# Increase partition size by 32MiB as well, but not the file system, as the LUKS2 encryption is around the filesystem
	image_resized="${TEMP_DIR}/resized.qcow2"
	execute cp "${image}" "${image_resized}"
	execute virt-resize --expand "/dev/vda${ROOT_PARTNUM}" --no-expand-content "${image}" "${image_resized}"
	# Remove smaller image, as we already made a copy
	execute rm -f "${image}"
	image="${image_resized}"

	# move image to output and compress
	# the longopt --compress to the short opt -c is broken
	execute qemu-img convert --target-format qcow2 -c "${image}" "${dest}" --quiet
	execute rm -f "${image}"
	image="${dest}"

	# mount guest image
	connect_nbd "${image}"
	root_part="${NBD}p${ROOT_PARTNUM}"

	# mount boot partition
	temp_boot="${TEMP_DIR}/boot"
	mount_partition "${NBD}p${BOOT_PARTNUM}" "${temp_boot}"

	# print kernel cmdline
	if [[ -f "${temp_boot}/sel-ebc.img" ]]; then
		kcmdline="$(strings "${temp_boot}/sel-ebc.img" | grep -E "^rd.sel-ebc")"

		log_info "found the following kernel cmdline:"
		log_info "${kcmdline}"
	else
		log_error "${temp_boot}/sel-ebc.img does not exist, unable to retrieve kernel cmdline"
	fi

	# Encrypt the root partition of the mounted guest
	log_info "encrypting partition"
	execute cryptsetup reencrypt --encrypt --reduce-device-size 32M \
			--cipher aes-xts-plain64 --key-size "${luks_segment_key_size}" \
			--volume-key-file "${segment_key}" --key-file "${passphrase}" "${root_part}" \
			--batch-mode --label=${luks_dev_name}
	log_info "done encrypting"

	log_info "reformat LUKS device from aes to paes"
	retr_sec_id=$(echo -n "${asr_name}" | sha256sum | cut -d " " -f 1)

	blob="00000000 09000000 000${retr_sec_type}0000 ${retr_sec_id}"
	blob_file="$(mktemp)"
	echo "${blob}" | xxd -r -p > "${blob_file}"
	printf "key blob: \n%s\n" "$(hexdump "${blob_file}")"
	if [[ "$(wc -c "${blob_file}" | cut -d " " -f 1 )" != "44" ]]; then
		log_error "size of ${blob_file} != 44"
	fi

	# parse LUKS header
	dump=$(mktemp)
	execute cryptsetup luksDump "${root_part}" > "${dump}"
	sector_size=$(grep "sector:" "${dump}" | awk 'NR==1{print $2}')
	metadata_size=$(grep "Metadata area:" "${dump}" | awk 'NR==1{print $3}')
	keyslots_size=$(grep "Keyslots area:" "${dump}" | awk 'NR==1{print $3}')

	# Reformat LUKS header of guest root fs from AES to PAES
	execute cryptsetup luksFormat "${root_part}" --batch-mode \
			--key-file "${passphrase}" \
			--uuid "${UUID}" --cipher paes-xts-plain64 \
			--sector-size "${sector_size}" \
			--luks2-metadata-size "${metadata_size}" \
			--luks2-keyslots-size "${keyslots_size}" \
			--volume-key-file "${blob_file}" --key-size 352 \
			--label=${luks_dev_name}

	sics="${temp_boot}/sics"
	if [[ ! -d "${sics}" ]]; then
		execute mkdir "${sics}"
	fi

	# Build pv_cmd array using helper function
	build_pv_cmd "${hkds}" "${NO_VERIFY}" "${certs}" "${crls}" "${rootca}" "${offline}"

	# prepare pvsecret command
	pvsecret_cmd_static=("pvsecret" "create")
	pvsecret_cmd_static+=("${pv_cmd[@]}" "--extension-secret" "${extension_secret}" "--quiet")
	header="${TEMP_DIR}/selhdr.bin"
	execute pvextract-hdr -o "${header}" "${temp_boot}/sel-ebc.img"
	pvsecret_cmd_static+=("--hdr" "${header}")

	# generate ASR for LUKS segment key
	pv_in="${segment_key}"
	pv_out="${sics}/${asr_name}.asr"
	pvsecret_cmd=("${pvsecret_cmd_static[@]}" "--toc-policy" "${sics}/toc.pol" "--output" "${pv_out}" "retrievable" "--secret" "${pv_in}" "--type" "aes-xts" "${asr_name}")
	execute "${pvsecret_cmd[@]}"
	log_info "generated Add-Secret-Request ${pv_out} from ${pv_in} containing the LUKS encryption key for the root filesystem"

	# generate ASR for CCK
	pv_in="${cck}"
	pv_out="${sics}/cck.asr"
	pvsecret_cmd=("${pvsecret_cmd_static[@]}" "--toc-policy" "${sics}/toc.pol" "--output" "${pv_out}" "update-cck" "--secret" "${pv_in}")
	execute "${pvsecret_cmd[@]}"
	log_info "generated Add-Secret-Request ${pv_out} from ${pv_in} containing the Customer-Communication-Key"

	# generate ASR for LUKS passphrase
	pv_out="${sics}/luks-rfs-passphrase.asr"
	pv_in="${passphrase}"
	pvsecret_cmd=("${pvsecret_cmd_static[@]}" "--toc-policy" "${sics}/toc.pol" "--output" "${pv_out}" "retrievable" "--secret" "${pv_in}" "--type" "plain" "luks-rfs-passphrase")
	execute "${pvsecret_cmd[@]}"
	log_info "generated Add-Secret-Request ${pv_out} from ${pv_in} containing the LUKS passphrase for the root filesystem"

	# add additional ASRs to toc.pol
	if [[ "${asrs}" != "unset" ]]; then
		for asr in ${asrs}; do
			files=$(ls "${asr}")
			for f in ${files}; do
				add_asr_to_toc "${f}" "${sics}/toc.pol"
				execute cp "${f}" "${sics}/"
				log_info "added user provided Add-Secret-Request ${f}"
			done
		done
	fi

	# generate toc.asr
	pvsecret_cmd=("${pvsecret_cmd_static[@]}" "--output" "${sics}/toc.asr" "--policy" "toc.pol" "meta")
	execute cp "${sics}/toc.pol" "toc.pol"
	execute "${pvsecret_cmd[@]}"
	execute rm -f toc.pol

	# check sanity of SICS
	pv_cmd=("pvebc" "--dry-run" "--toc" "${sics}/toc.asr")
	execute "${pv_cmd[@]}"
	log_info "${sics} is sane"

	# unmount image
	cleanup_pop  # Unmount temp_boot
	cleanup_pop  # Disconnect NBD

	return 0
}


#
# MAIN
#

main() {
	# Set strict error handling when running as script
	local -
	set -Eu

	# call cleanup on error
	# PIPE is needed to allow out=$(main list -i <image> | grep -m 1 <filter>)
	#   bash will close the subshell executing the main function as soon as grep has found a match
	#   cleanup will not be executed anymore
	trap 'cleanup 1' ERR EXIT PIPE

	# general
	ACTION=""
	NBD=""
	ARCH=""
	CONFIG_FILE=""
	OUT=""
	UUID=""
	TEMP_DIR=""
	NO_VERIFY=""
	NO_EBC=""
	BOOT_PARTNUM=""
	ROOT_PARTNUM=""
	HKDs=""
	IMAGE=""
	PARTNUM=""

	# certificate chain related
	CC_CERTS=""
	CC_CRLS=""
	CC_ROOTCA=""
	CC_OFFLINE=""

	# conversion related
	C_BOOT_LOADER_ENTRY=""
	C_SEL_KERNEL_PARAMETER=""

	# encryption related
	E_CCK=""
	E_EXTENSION_SECRET=""
	E_LUKS_RFS_KEY=""
	E_LUKS_PASSPHRASE=""
	E_LUKS_RFS_KEY_ASR_NAME=""
	E_LUKS_KEY_SIZE=""
	E_ADD_SECRET_REQUESTS=""

	# parse command line
	cli "$@"

	# set up logger
	setup_logger

	# get architecture
	get_arch

	# check for prereqs
	check_prereqs

	if [[ "${ACTION}" != "list" ]]; then
		# parse yaml configuration
		parse_yaml

		# setup output directory
		if [[ ! -d ${OUT} ]]; then
			execute mkdir "${OUT}"
			if [[ ! -d ${OUT} ]]; then
				log_error "unable to create ${OUT}"
			fi
		fi
	fi

	# get partitions
	get_partnum "root" "${IMAGE}"
	ROOT_PARTNUM="${PARTNUM}"
	test -z "${ROOT_PARTNUM}" && log_error "unable to find root partition on ${IMAGE}"
	get_partnum "boot" "${IMAGE}"
	BOOT_PARTNUM="${PARTNUM}"
	test -z "${BOOT_PARTNUM}" && log_error "unable to find boot partition on ${IMAGE}"

	# setup temporary directory
	UUID=$(uuidgen)
	TEMP_DIR=/opt/sel-ebc-${UUID}
	execute mkdir "${TEMP_DIR}"
	if [[ ! -d ${TEMP_DIR} ]]; then
		log_error "unable to create ${TEMP_DIR}"
	fi
	# Register cleanup for TEMP_DIR (will be removed on any exit)
	if [[ -d "${TEMP_DIR}" ]]; then
		cleanup_push rm -rf "${TEMP_DIR}"
	fi
	execute mkdir "${TEMP_DIR}/boot"
	execute mkdir "${TEMP_DIR}/root"

	log_info "all temporary resources will be placed in ${TEMP_DIR}"

	if [[ "${ACTION}" == "list" ]]; then
		list
	fi

	if [[ "${ACTION}" == "convert" || "${ACTION}" == "full" ]]; then
		convert
	fi

	if [[ "${ACTION}" == "encrypt" || "${ACTION}" == "full" ]]; then
		encrypt
	fi

	# Done - run cleanup explicitly to support sourcing
	log_info "done"

	# Run cleanup stack to reset logging and clean up resources
	# This ensures cleanup happens even when script is sourced
	cleanup 0
	return $?
}


#
# SOURCE WRAPPER
#

if [[ "$0" == "${BASH_SOURCE[0]}" ]]; then
	main "${@}"
fi