Tomb/tomb

#!/usr/bin/env zsh
#
# Tomb, the Crypto Undertaker
#
# A commandline tool to easily operate encryption of secret data
#

# {{{ License

# Copyright (C) 2007-2023 Dyne.org Foundation
#
# Tomb is designed, written and maintained by Denis Roio <jaromil@dyne.org>
#
# Please refer to the AUTHORS file for more information.
#
# This source code is free software; you can redistribute it and/or
# modify it under the terms of the GNU Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This source code is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	Please refer
# to the GNU Public License for more details.
#
# You should have received a copy of the GNU Public License along with
# this source code; if not, , see <https://www.gnu.org/licenses/>.

# }}} - License

# {{{ Global variables

typeset VERSION="2.10.0"
typeset DATE="Sep/2023"
typeset TOMBEXEC=$0
typeset TMPDIR=${${TMPPREFIX%/*}:-/tmp}
# TODO: configure which tmp dir to use from a cli flag

# Tomb is using some global variables set by the shell:
# TMPPREFIX, UID, GID, PATH, TTY, USERNAME
# You can grep 'global variable' to see where they are used.

# Keep a reference of the original command line arguments
typeset -a OLDARGS
for arg in "${(@)argv}"; do OLDARGS+=("$arg"); done

# Special command requirements
typeset -a DD WIPE PINENTRY SUDO
DD=(dd)
WIPE=(rm -f)
PINENTRY=(pinentry)
SUDO=(sudo)

# load zsh regex module
zmodload zsh/mapfile
zmodload -F zsh/stat b:zstat

# make sure variables aren't exported
unsetopt allexport

# Flag optional commands if available (see _ensure_dependencies())
typeset -i KDF=1
typeset -i STEGHIDE=1
typeset -i CLOAKIFY=1
typeset -i DECLOAKIFY=1
typeset -i SPHINX=1
typeset -i RESIZER=1
typeset -i SWISH=1
typeset -i QRENCODE=1

# Default mount options
typeset		 MOUNTOPTS="rw,noatime,nodev"

# Makes glob matching case insensitive
unsetopt CASE_MATCH

typeset -AH OPTS			  # Command line options (see main())

# Command context (see _whoami())
typeset -H _USER			  # Running username
typeset -Hi _UID			  # Running user identifier
typeset -Hi _GID			  # Running user group identifier
typeset -H  _TTY			  # Connected input terminal

# Tomb context (see is_valid_tomb())
typeset -H TOMBPATH			  # Full path to the tomb
typeset -H TOMBDIR			  # Directory where the tomb is
typeset -H TOMBFILE			  # File name of the tomb
typeset -H TOMBNAME			  # Name of the tomb

# Tomb secrets
typeset -H TOMBKEY			  # Encrypted key contents (see forge_key(), recover_key())
typeset -H TOMBKEYFILE		  # Key file			   (ditto)
typeset -H TOMBSECRET		  # Raw deciphered key	   (see forge_key(), gpg_decrypt())
typeset -H TOMBPASSWORD		  # Raw tomb passphrase	   (see gen_key(), ask_key_password())
typeset -H TOMBTMP			  # Filename of secure temp just created (see _tmp_create())

typeset -aH TOMBTMPFILES	  # Keep track of temporary files
typeset -aH TOMBLOOPDEVS	  # Keep track of used loop devices
typeset -A TOMBFILESSTAT      # Keep track of access date attributes

typeset _MSG_FD_OVERRIDE # if set, _msg will write to this file descriptor

# Make sure sbin is in PATH (man zshparam)
path+=( /sbin /usr/sbin )

# For gettext
export TEXTDOMAIN=tomb

# }}}

# {{{ Safety functions

# Wrap sudo with a more visible message or apply user-supplied alternative to sudo
_sudo() {
	if option_is_set --sudo; then
               pescmd=`option_value --sudo`
		case `basename $pescmd` in
			"doas"|"sup"|"sud"|"pkexec")
				command -v $pescmd > /dev/null || _failure "$pescmd executable not found"
				_verbose "Super user execution using $pescmd"
				${pescmd} ${@}
				return $?
				;;
			"skip"|"none")
				_verbose "Super user execution skipped (SUID caller)"
				${@}
				return $?
				;;
			 *)
				_failure "Super user execution not supported: ::1 sudo::" "`option_value --sudo`"
				;;
		esac

	else
		local msg="[sudo] Enter password for user ::1 user:: to gain superuser privileges"
		command -v gettext 1>/dev/null 2>/dev/null && msg="$(gettext -s "$msg")"
		msg=${(S)msg//::1*::/$USER}
		[[ -n "$SUDO_ASKPASS" ]] && local sudo_askpass="--askpass"
		sudo $sudo_askpass -p "
$msg

" ${@}
		return $?
	fi
}

# Cleanup anything sensitive before exiting.
_endgame() {

	option_value_contains -o ro || {
		# Restore access time of sensitive files
		[[ -z $TOMBFILESSTAT ]] || _restore_stat
	}

	# Prepare some random material to overwrite vars
	local rr="$RANDOM"
	while [[ ${#rr} -lt 500 ]]; do
		rr+="$RANDOM"
	done

	# Ensure no information is left in unallocated memory
	TOMBPATH="$rr";		 unset TOMBPATH
	TOMBDIR="$rr";		 unset TOMBDIR
	TOMBFILE="$rr";		 unset TOMBFILE
	TOMBNAME="$rr";		 unset TOMBNAME
	TOMBKEY="$rr";		 unset TOMBKEY
	TOMBKEYFILE="$rr";	 unset TOMBKEYFILE
	TOMBSECRET="$rr";	 unset TOMBSECRET
	TOMBPASSWORD="$rr";	 unset TOMBPASSWORD

	# Clear temporary files
	for f in $TOMBTMPFILES; do
		${=WIPE} "$f"
	done
	unset TOMBTMPFILES

	# Detach loop devices
	for l in $TOMBLOOPDEVS; do
		_sudo losetup -d "$l"
	done
	unset TOMBLOOPDEVS

}

# Trap functions for the _endgame event
TRAPINT()  { _endgame INT;	}
TRAPEXIT() { _endgame EXIT;	}
TRAPHUP()  { _endgame HUP;	}
TRAPQUIT() { _endgame QUIT;	}
TRAPABRT() { _endgame ABORT;    }
TRAPKILL() { _endgame KILL;	}
TRAPPIPE() { _endgame PIPE;	}
TRAPTERM() { _endgame TERM;	}
TRAPSTOP() { _endgame STOP;	}

_is_found() {
	# returns 0 if binary is found in path
	[[ -z $1 ]] && return 1
	command -v "$1" 1>/dev/null 2>/dev/null
	return $?
}

# Track acces and modification time of tomb files.
# $1: file to track
# date format: seconds since Epoch
# stat format: <last access>:<last modified>
_track_stat() {
    local file="$1"
    local stat=$(stat --format="%X:%Y" "$file")
    TOMBFILESSTAT+=("$file" "$stat")
}

# Restore files stats
_restore_stat() {
    local file stat
    for file stat in "${(@kv)TOMBFILESSTAT}"; do
        stats=("${(@s.:.)stat}")
        _verbose "Restoring access and modification time for ::1 file::" $file
        [[ -z "${stats[1]}" ]] || touch -a --date="@${stats[1]}" "$file"
        [[ -z "${stats[2]}" ]] || touch -m --date="@${stats[2]}" "$file"
    done
}

# Identify the running user
# Set global variables _UID, _GID, _TTY, and _USER, either from the
# command line, -U, -G, -T, respectively, or from the environment.
# Also update USERNAME and HOME to maintain consistency.
_whoami() {

	# Set username from UID or environment
	_USER=$SUDO_USER
	[[ -z $_USER ]] && { _USER=$USERNAME }
	[[ -z $_USER ]] && { _USER=$(id -un) }
	[[ -z $_USER ]] && {
		_failure "Failing to identify the user who is calling us" }

	# Get GID from option -G or the environment
	option_is_set -G \
		&& _GID=$(option_value -G) || _GID=$(id -g $_USER)

	# Get UID from option -U or the environment
	option_is_set -U \
		&& _UID=$(option_value -U) || _UID=$(id -u $_USER)

	_verbose "Identified caller: ::1 username:: (::2 UID:::::3	GID::)" $_USER $_UID $_GID

	# Update USERNAME accordingly if possible
	# [[ $EUID == 0 && $_USER != $USERNAME ]] && {
	#	  _verbose "Updating USERNAME from '::1 USERNAME::' to '::2 _USER::')" $USERNAME $_USER
	#	  USERNAME=$_USER
	# }

	# Force HOME to _USER's HOME if necessary
	local home=`_get_home $_USER`
	[[ $home == $HOME ]] || {
		_verbose "Updating HOME to match user's: ::1 home:: (was ::2 HOME::)" \
				 $home $HOME
		HOME=$home }

	# Get connecting TTY from option -T or the environment
	option_is_set -T && _TTY=$(option_value -T)
	[[ -z $_TTY ]]	 && _TTY=$TTY

}

# Provide a random filename in shared memory
_tmp_create() {
	[[ -d "$TMPDIR" ]] || {
		# we create the tempdir with the sticky bit on
		_sudo mkdir -m 1777 "$TMPDIR"
		[[ $? == 0 ]] || _failure "Fatal error creating the temporary directory: ::1 temp dir::" "$TMPDIR"
	}

	# We're going to add one more $RANDOM for each time someone complains
	# about this being too weak of a random.
	tfile="${TMPDIR}/$RANDOM$RANDOM$RANDOM$RANDOM"	# Temporary file
	umask 066
	[[ $? == 0 ]] || {
		_failure "Fatal error setting the permission umask for temporary files" }

	[[ -r "$tfile" ]] && {
		_failure "Someone is messing up with us trying to hijack temporary files." }

	touch "$tfile"
	[[ $? == 0 ]] || {
		_failure "Fatal error creating a temporary file: ::1 temp file::" "$tfile" }

	_verbose "Created tempfile: ::1 temp file::" "$tfile"
	TOMBTMP="$tfile"
	TOMBTMPFILES+=("$tfile")

	return 0
}

# Check if a *block* device is encrypted
# Check if a *block* device is a zram device
# Synopsis: _is_zramswap /path/to/block/device
# Return 0 if it is a zramswap
# Return 1 if it is not a zramswap
_is_zramswap() {
	local	b=$1 # Path to a block device

	# check if device b is a zram block device
	zramctl --raw -o NAME | grep "^$b" >/dev/null

	return $?
}

# Check if a zram device uses the writeback feature that writes data onto a disk
# Synopsis: _zramswap_uses_writeback /path/to/block/device
# Return 0 if the zram device writes to disk
# Return 1 if the zram device does not write to disk
_zramswap_uses_writeback() {
	local	b=$1 # Path to a block device
	local	m="" # major device number
	local	n="" # minor device number

	read n m < <(stat -c '%T %t' $b) # get major and minor device number in hex
	printf -v m %d $((16#$m)) # get major device number in decimal
	printf -v n %d $((16#$n)) # get minor device number in decimal

	if grep '^none$' "/sys/dev/block/$m:$n/backing_dev" > /dev/null; then
		return 1
	fi

	return 0
}

# Check if a *block* device is a zram device
# Synopsis: _is_zramswap /path/to/block/device
# Return 0 if it is a zramswap
# Return 1 if it is not a zramswap
_is_zramswap() {
	local	b=$1 # Path to a block device

	zramctl --raw -o NAME | grep "^$b" >/dev/null
	# @todo How to do this without zramctl?
	# - device node major is dynamically allocated to zram0
	# - in /sys/ there seems to be no file identifying a zram device

	return $?
}

# Check if a zram device uses the writeback feature that writes data onto a disk
# Synopsis: _zramswap_uses_writeback /path/to/block/device
# Return 0 if the zram device writes to disk
# Return 1 if the zram device does not write to disk
_zramswap_uses_writeback() {
	local	b=$1 # Path to a block device
	local	m="" # major device number
	local	n="" # minor device number

	read n m < <(stat -c '%T %t' $b) # get major and minor device number in hex
	printf -v m %d $((16#$m)) # get major device number in decimal
	printf -v n %d $((16#$n)) # get minor device number in decimal

	if grep '^none$' "/sys/dev/block/$m:$n/backing_dev" > /dev/null; then
		return 1
	fi

	return 0
}

# Synopsis: _is_encrypted_block /path/to/block/device
# Return 0 if it is an encrypted block device
_is_encrypted_block() {
	local	 b=$1 # Path to a block device
	local	 s="" # lsblk option -s (if available)

	# Issue #163
	# lsblk --inverse appeared in util-linux 2.22
	# but --version is not consistent...
	lsblk --help | grep -Fq -- --inverse
	[[ $? -eq 0 ]] && s="--inverse"

	_sudo lsblk $s -o type -n $b 2>/dev/null \
		| egrep -q '^crypt$'

	return $?
}

# Check if swap is activated
# Return 0 if NO swap is used, 1 if swap is used.
# Return 1 if any of the swaps is not encrypted.
# Return 2 if swap(s) is(are) used, but ALL encrypted or zramswap without writeback to disk.
# Use _check_swap in functions. It will call this function and
# exit if unsafe swap is present.
_ensure_safe_swap() {

	local -i r=1	# Return code: 0 no swap, 1 unsafe swap, 2 encrypted
	local -a swaps	# List of swap partitions
	local	 bone is_crypt

	swaps="$(awk '/^\// { print $1 }' /proc/swaps 2>/dev/null)"
	[[ -z "$swaps" ]] && return 0 # No swap partition is active

	_message "An active swap partition is detected..."
	for s in $=swaps; do
		if _is_encrypted_block $s; then
			r=2;
		elif _is_zramswap $s; then
			if _zramswap_uses_writeback $s; then
				# We're dealing with unencrypted stuff written to disk.
				# Maybe it lives on an encrypted filesystem anyway.
				# @todo verify it's actually written to an encrypted FS
				# Well, no: bail out.
				_message "Found zramswap with writeback enabled."
				r=1; break;
			else
				_message "Found zramswap without writeback to disk."
				r=2
			fi
		else
			# We're dealing with unencrypted stuff written to disk.
			# Maybe it lives on an encrypted filesystem anyway.
			# @todo: verify it's actually on an encrypted FS (see #163 and !189)
			# Well, no: bail out.
			r=1; break;
		fi
	done

	if [[ $r -eq 2 ]]; then
		_success "The undertaker found that all swap partitions are encrypted. Good."
	else
		_warning "This poses a security risk."
		_warning "You can deactivate all swap partitions using the command:"
		_warning " swapoff -a"
		_warning "[#163] I may not detect plain swaps on an encrypted volume."
		_warning "But if you want to proceed like this, use the -f (force) flag."
	fi
	return $r

}

# Wrapper to allow encrypted swap and remind the user about possible
# data leaks to disk if swap is on, which shouldn't be ignored. It could
# be run once in main(), but as swap evolves, it's better to run it
# whenever swap may be needed.
# Exit if unencrypted swap is active on the system.
_check_swap() {
	if ! option_is_set -f && ! option_is_set --ignore-swap; then
		_ensure_safe_swap
		case $? in
			0|2)	 # No, or encrypted swap
				return 0
				;;
			*)		 # Unencrypted swap
				_failure "Operation aborted."
				;;
		esac
	fi
}

pinentry_assuan_getpass() {
	# simply prints out commands for pinentry's stdin to activate the
	# password dialog
	cat <<EOF
OPTION ttyname=$TTY
OPTION lc-ctype=$LANG
SETTITLE $title
SETDESC $description
SETPROMPT Password:
GETPIN
EOF
}

# Ask user for a password
# Wraps around the pinentry command, from the GnuPG project, as it
# provides better security and conveniently use the right toolkit.
ask_password() {

	local description="$1"
	local title="${2:-Enter tomb password.}"
	local output
	local password
	local gtkrc
	local theme
	local pass_asked

	# Distributions have broken wrappers for pinentry: they do
	# implement fallback, but they disrupt the output somehow.	We are
	# better off relying on less intermediaries, so we implement our
	# own fallback mechanisms. Pinentry supported: curses, gtk-2, qt4, qt5
	# and x11.

	# make sure LANG is set, default to C
	LANG=${LANG:-C}

	_verbose "asking password with tty=$TTY lc-ctype=$LANG"

	pass_asked=0

	if [[ ! -z $WAYLAND_DISPLAY ]]; then
		_verbose "wayland display detected"
		_is_found "pinentry-gnome3" && {
			_verbose "using pinentry-gnome3 on wayland"
			output=$(pinentry_assuan_getpass | pinentry-gnome3)
			pass_asked=1
		}
	fi
	if [[ ! -z $DISPLAY ]] && [[ $pass_asked == 0 ]]; then
		_verbose "X11 display detected"
		if _is_found "pinentry-gtk-2"; then
			_verbose "using pinentry-gtk2"
			output=$(pinentry_assuan_getpass | pinentry-gtk-2)
			pass_asked=1
		elif _is_found "pinentry-x11"; then
			_verbose "using pinentry-x11"
			output=$(pinentry_assuan_getpass | pinentry-x11)
			pass_asked=1
		elif _is_found "pinentry-gnome3"; then
			_verbose "using pinentry-gnome3 on X11"
			output=$(pinentry_assuan_getpass | pinentry-gnome3)
			pass_asked=1
		elif _is_found "pinentry-qt5"; then
			_verbose "using pinentry-qt5"
			output=$(pinentry_assuan_getpass | pinentry-qt5)
			pass_asked=1
		elif _is_found "pinentry-qt4"; then
			_verbose "using pinentry-qt4"
			output=$(pinentry_assuan_getpass | pinentry-qt4)
			pass_asked=1
		fi
	fi
	if [[ $pass_asked == 0 ]]; then
		_verbose "no display detected"
		_is_found "pinentry-curses" && {
			_verbose "using pinentry-curses with no display"
			output=$(pinentry_assuan_getpass | pinentry-curses)
			pass_asked=1
		}
	fi

	[[ $pass_asked == 0 ]] &&
		_failure "Cannot find any pinentry-curses and no DISPLAY detected."

	# parse the pinentry output
	local pinentry_error
	for i in ${(f)output}; do
		[[ "$i" =~ "^ERR.*" ]] && {
			pinentry_error="${i[(w)3]}"
		}

		# here the password is found
		[[ "$i" =~ "^D .*" ]] && password="${i##D }";
	done

	[[ ! -z $pinentry_error ]] && [[ -z $password ]] && {
		_warning "Pinentry error: ::1 error::" ${pinentry_error}
		print "canceled"
		return 1
	}

	# if sphinx mode is chosen, use the provided input
	# as master password to retrieve the actual password
	if option_is_set --sphx-user || option_is_set --sphx-host; then
		password=$(sphinx_get_password "$password")
	fi

	[[ -z $password ]] && {
		_warning "Empty password"
		print "empty"
		return 1
	}

	print "$password"
	return 0
}

# Retrieve PASSWORD from sphinx
# $1 MASTER password for the password store
# requires --sphx-host and --sphx-user flags to be set
sphinx_get_password() {
	local errorfile
	local password
	if option_is_set --sphx-user && option_is_set --sphx-host; then
		# value error in sphinx doesn't set exit code
		# using tempfile as a workaround to notice the error
		errorfile=$(mktemp /tmp/tomb_error.XXXXXXXXX)
		password=$(echo "$1" | sphinx get $(option_value --sphx-user) $(option_value --sphx-host) 2>$errorfile)
		if  ! grep -q "ValueError: fail" $errorfile ; then
			echo "$password"
			rm $errorfile
			return 0
		else
			_warning "sphinx returns error: ::1 error::" $(cat $errorfile)
			rm $errorfile
			_failure "Failed to retrieve actual password with sphinx."
		fi
	else
		_failure "Both host and user have to be set to use sphinx"
	fi
}

# Create PASSWORD in sphinx
# $1 MASTER password for the password store
# requires --sphx-host and --sphx-user flags to be set
sphinx_set_password() {
	local errorfile
	local password
	if option_is_set --sphx-user && option_is_set --sphx-host; then
		# value error in sphinx doesn't set exit code
		# using tempfile as a workaround to notice the error
		errorfile=$(mktemp /tmp/tomb_error.XXXXXXXXX)
		# check first if this host/user combination exists in store
		# if yes, there is no need to make a call to create
		password=$(echo "$1" | sphinx get $(option_value --sphx-user) $(option_value --sphx-host) 2>$errorfile)
		if  ! grep -q "error: sphinx protocol failure" $errorfile ; then
			echo "$password"
			rm $errorfile
			return 0
		fi
		# no such host/user combination in store, create one
		password=$(echo "$1" | sphinx create $(option_value --sphx-user) $(option_value --sphx-host) ulsd 0 2>$errorfile)
		if  ! grep -q "error: sphinx protocol failure" $errorfile ; then
			echo "$password"
			rm $errorfile
			return 0
		else
			_warning "sphinx returns error: ::1 error::" $(cat $errorfile)
			rm $errorfile
			_failure "Failed to create password with sphinx"
		fi
	else
		_failure "Both host and user have to be set to use sphinx"
	fi
}

# Check if a filename is a valid tomb
is_valid_tomb() {

	_verbose "is_valid_tomb ::1 tomb file::" $1

	# First argument must be the path to a tomb
	[[ ! -z $1 ]] ||	_failure "Tomb file is missing from arguments."

	local _fail=0
	# Tomb file must be a readable, writable, non-empty regular file.
	# If passed the "ro" mount option, the writable check is skipped.
	option_value_contains -o ro || {
		[[ ! -w "$1" ]] && {
			_warning "Tomb file is not writable: ::1 tomb file::" $1
			_fail=1
		}
	}
	_verbose "tomb file is readable"

	[[ ! -f "$1" ]] && {
		_warning "Tomb file is not a regular file: ::1 tomb file::" $1
		_fail=1
	}
	_verbose "tomb file is a regular file"

	[[ ! -s "$1" ]] && {
		_warning "Tomb file is empty (zero length): ::1 tomb file::" $1
		_fail=1
	}
	_verbose "tomb file is not empty"

	[[ $_fail == 1 ]] && {
		_failure "Tomb command failed: ::1 command name::" $subcommand
	}

	# Tomb file may be a LUKS FS (or we are creating it)
	[[ "`file $1`" =~ "luks encrypted file" ]] || {
		_message "File is not yet a tomb: ::1 tomb file::" $1 }

	# We set global variables
	typeset -g TOMBPATH TOMBDIR TOMBFILE TOMBNAME TOMBMAPPER

	TOMBPATH="$1"

	TOMBDIR=$(dirname $TOMBPATH)

	TOMBFILE=$(basename $TOMBPATH)

	# The tomb name is TOMBFILE without an extension and underscores instead of spaces (for mount and cryptsetup)
	# It can start with dots: ..foo bar baz.tomb -> ..foo_bar_baz
	TOMBNAME=${${TOMBFILE// /_}%.*}
	# use the entire filename if the previous transformation returns
	# an empty string. This handles the corner case of tomb being
	# hidden files (starting with a dot) and have no extension (only
	# one dot in string)
	TOMBNAME=${TOMBNAME:-${TOMBFILE}}
	[[ -z $TOMBNAME ]] &&
		_failure "Tomb won't work without a TOMBNAME."

	# checks if Tomb already mounted (or we cannot alter it)
	local maphash=`realpath $TOMBPATH | sha256sum -z`
	lo_mount # fills TOMBLOOP with next loop
	TOMBMAPPER="tomb.$TOMBNAME.${maphash[(w)1]}.`basename $TOMBLOOP`"
	local mounted_tombs=(`list_tomb_mounts`)
	local usedmapper
	for t in ${mounted_tombs}; do
		usedmapper=`basename "${t[(ws:;:)1]}"`
		[[ "${usedmapper%.*}" == "${TOMBMAPPER%.*}" ]] &&
			_failure "Tomb file already in use: ::1 tombname::" $TOMBPATH
	done
	_verbose "Mapper: ::1 mapper::" $TOMBMAPPER

	_verbose "tomb file is not currently in use"

	_message "Valid tomb file found: ::1 tomb path::" $TOMBPATH
	return 0
}


# $1 is the tomb file to be lomounted
lo_mount() {
	tpath="$1"

	# check if we have support for loop mounting
	TOMBLOOP=`_sudo losetup -f`
	[[ $? = 0 ]] || {
		_warning "Loop mount of volumes is not possible on this machine, this error"
		_warning "often occurs on VPS and kernels that don't provide the loop module."
		_warning "It is impossible to use Tomb on this machine under these conditions."
		_failure "Operation aborted."
	}

	[[ "$tpath" == "" ]] && return 0


	# allocates the next loopback for our file
	_sudo losetup -f "$tpath" || _failure "Loopback mount failed: ::1 path:: on ::2 loop::" "$tpath" $TOMBLOOP

	TOMBLOOPDEVS+=("$TOMBLOOP") # add to array of lodevs used

	return 0
}

# print out latest loopback mounted
lo_new() { print - "${TOMBLOOPDEVS[${#TOMBLOOPDEVS}]}" }

# $1 is the path to the lodev to be preserved after quit
lo_preserve() {
	_verbose "lo_preserve on ::1 path::" $1
	# remove the lodev from the tomb_lodevs array
	TOMBLOOPDEVS=("${(@)TOMBLOOPDEVS:#$1}")
}

# eventually used for debugging
dump_secrets() {
	print "TOMBPATH: $TOMBPATH"
	print "TOMBNAME: $TOMBNAME"

	print "TOMBKEY len: ${#TOMBKEY}"
	print "TOMBKEYFILE: $TOMBKEYFILE"
	print "TOMBSECRET len: ${#TOMBSECRET}"
	print "TOMBPASSWORD: $TOMBPASSWORD"

	print "TOMBTMPFILES: ${(@)TOMBTMPFILES}"
	print "TOMBLOOPDEVS: ${(@)TOMBLOOPDEVS}"
}

# }}}

# {{{ Commandline interaction

usage() {
	_print "Syntax: tomb [options] command [arguments]"
	echo
	_print "Commands:"
	echo
	_print " // Creation:"
	_print " dig          create a new empty TOMB file of size -s in MiB"
	_print " forge        create a new KEY file and set its password"
	_print " lock         installs a lock on a TOMB to use it with KEY"
	echo
	_print " // Operations on tombs:"
	_print " open         open an existing TOMB (-k KEY file or - for stdin)"
	_print " index        update the search indexes of tombs"
	_print " search       looks for filenames matching text patterns"
	_print " list         list of open TOMBs and information on them"
	_print " ps           list of running processes inside open TOMBs"
	_print " close        close a specific TOMB (or 'all')"
	_print " slam         slam a TOMB killing all programs using it"
	[[ $RESIZER == 1 ]] && {
		_print " resize       resize a TOMB to a new size -s (can only grow)"
	}
	echo
	_print " // Operations on keys:"
	_print " passwd       change the password of a KEY (needs old pass)"
	_print " setkey       change the KEY locking a TOMB (needs old key and pass)"
	echo
	[[ $QRENCODE == 1 ]] && {
		_print " // Backup on paper:"
		_print " engrave      makes a QR code of a KEY to be saved on paper"
		echo
	}
	[[ $STEGHIDE == 1 || $CLOAKIFY == 1 || $DECLOAKIFY == 1 ]] && {
		_print " // Steganography:"
		[[ $STEGHIDE == 1 ]] && {
			_print " bury         hide a KEY inside a JPEG image (for use with -k)"
			_print " exhume       extract a KEY from a JPEG image (prints to stdout)"
		}
		[[ $CLOAKIFY == 1 ]] && {
			_print " cloak        transform a KEY into TEXT using CIPHER (for use with -k)"
		}
		[[ $DECLOAKIFY == 1 ]] && {
			_print " uncloak      extract a KEY from a TEXT using CIPHER (prints to stdout)"
		}
		echo
	}
	_print "Options:"
	echo
	_print " -s           size of the tomb file when creating/resizing one (in MiB)"
	_print " -k           path to the key to be used ('-k -' to read from stdin)"
	_print " -n           don't launch the execution hooks found in tomb"
	_print " -p           preserve the ownership of all files in tomb"
	_print " -o           options passed to commands: open, lock, forge (see man)"
	_print " -f           force operation (i.e. even if swap is active)"
	_print " -g           use a GnuPG key to encrypt a tomb key"
	_print " -r           provide GnuPG recipients (separated by comma)"
	_print " -R           provide GnuPG hidden recipients (separated by comma)"
	_print " --sudo       super user exec alternative to sudo (doas or none)"

	[[ $SPHINX == 1 ]] && {
		_print " --sphx-user  user associated with the key (for use with pitchforkedsphinx)"
		_print " --sphx-host  host associated with the key (for use with pitchforkedsphinx)"
	}

	[[ $KDF == 1 ]] && {
		_print " --kdf        forge keys armored against dictionary attacks"
	}

	echo
	_print " -h           print this help"
	_print " -v           print version, license and list of available ciphers"
	_print " -q           run quietly without printing informations"
	_print " -D           print debugging information at runtime"
	echo
	_print "For more information on Tomb read the manual: man tomb"
	_print "Please report bugs on <http://github.com/dyne/tomb/issues>."
}


# Check whether a commandline option is set.
#
# Synopsis: option_is_set -flag [out]
#
# First argument is the commandline flag (e.g., "-s").
# If the second argument is present and set to 'out', print out the
# result: either 'set' or 'unset' (useful for if conditions).
#
# Return 0 if is set, 1 otherwise
option_is_set() {
	local -i r	 # the return code (0 = set, 1 = unset)

	[[ -n ${(k)OPTS[$1]} ]];
	r=$?

	[[ $2 == "out" ]] && {
		[[ $r == 0 ]] && { print 'set' } || { print 'unset' }
	}

	return $r;
}

# Print the option value matching the given flag
# Unique argument is the commandline flag (e.g., "-s").
option_value() {
	print -n - "${OPTS[$1]}"
}

# check if the option value contains a string between commas
option_value_contains() {
	local opt="${OPTS[$1]}"
	local str="$2"
	for i in ${(s:,:)opt}; do
		[[ "$i" == "$2" ]] && return 0
	done
	return 1
}

# Messaging function with pretty coloring
function _msg() {
	local msg="$2"
	local i
	command -v gettext 1>/dev/null 2>/dev/null && msg="$(gettext -s "$2")"
	for i in {3..${#}}; do
		msg=${(S)msg//::$(($i - 2))*::/$*[$i]}
	done

	local command="print -P"
	local progname="${TOMBEXEC##*/}"
	local pchars=""
	local pcolor="normal"
	local fd=2
	local -i returncode

	case "$1" in
		inline)
			command+=" -n"; pchars=" > "; pcolor="yellow"
			;;
		message)
			pchars=" . "; pcolor="white"
			;;
		verbose)
			pchars="[D]"; pcolor="blue"
			;;
		success)
			pchars="(*)"; pcolor="green"
			;;
		warning)
			pchars="[W]"; pcolor="yellow"
			;;
		failure)
			pchars="[E]"; pcolor="red"
			returncode=1
			;;
		print)
			progname=""
			fd=1
			;;
		*)
			pchars="[F]"; pcolor="red"
			msg="Developer oops!  Usage: _msg MESSAGE_TYPE \"MESSAGE_CONTENT\""
			returncode=127
			;;
	esac

	[[ -n $_MSG_FD_OVERRIDE ]] && fd=$_MSG_FD_OVERRIDE

	if [[ -t $fd ]]; then
	       [[ -n "$progname" ]] && progname="$fg[magenta]$progname$reset_color"
	       [[ -n "$pchars" ]] && pchars="$fg_bold[$pcolor]$pchars$reset_color"
	       msg="$fg[$pcolor]$msg$reset_color"
	fi

	${=command} "${progname}" "${pchars}" "${msg}" >&$fd
	return $returncode
}

function _message() {
	local notice="message"
	[[ "$1" = "-n" ]] && shift && notice="inline"
	option_is_set -q || _msg "$notice" $@
	return 0
}

function _verbose() {
	option_is_set -D && _msg verbose $@
	return 0
}

function _success() {
	option_is_set -q || _msg success $@
	return 0
}

function _warning() {
	option_is_set -q || _msg warning $@
	return 1
}

function _failure() {
	typeset -i exitcode=${exitv:-1}
	option_is_set -q || _msg failure $@
	# be sure we forget the secrets we were told
	exit $exitcode
}

function _print() {
	option_is_set -q || _msg print $@
	return 0
}

_list_optional_tools() {
	typeset -a _deps
	_deps=(gettext dcfldd shred steghide)
	_deps+=(resize2fs tomb-kdb-pbkdf2 argon2 qrencode swish-e unoconv lsof)
	for d in $_deps; do
		_print "`which $d`"
	done
	return 0
}


# Check program dependencies
#
# Tomb depends on system utilities that must be present, and other
# functionality that can be provided by various programs according to
# what's available on the system.  If some required commands are
# missing, bail out.
_ensure_dependencies() {

	# Check for required programs
	for req in cryptsetup pinentry sudo gpg mkfs.ext4 e2fsck; do
		command -v $req 1>/dev/null 2>/dev/null || {
			_failure "Missing required dependency ::1 command::.  Please install it." $req; }
	done

	# Ensure system binaries are available in the PATH
	path+=(/sbin /usr/sbin) # zsh magic

	# use pkexec in place of sudo if found in path and polkitd is running
	# command -v pkexec 1>/dev/null 2>/dev/null
	# [[ $? == 0 ]] && ps ax | grep '[p]olkitd' 1>/dev/null 2>/dev/null && {
	#     SUDO=(pkexec)	}
	[[ "$SUDO" == "sudo" ]] && {
	    command -v sudo 1>/dev/null 2>/dev/null ||
		_failure "No privilege escalation tool found, not even sudo"
	}

	# Which dd command to use
	command -v dcfldd 1>/dev/null 2>/dev/null && DD=(dcfldd statusinterval=1)

	# Which wipe command to use
	command -v shred 1>/dev/null 2>/dev/null && WIPE=(shred -f -u)

	# Check for lsof for slamming tombs
	command -v lsof 1>/dev/null 2>/dev/null || LSOF=0
	# Check for steghide
	command -v steghide 1>/dev/null 2>/dev/null || STEGHIDE=0
	# Check for cloakify
	command -v cloakify 1>/dev/null 2>/dev/null || CLOAKIFY=0
	# Check for decloakify
	command -v decloakify 1>/dev/null 2>/dev/null || DECLOAKIFY=0
	# Check for pitchforkedsphinx client
	command -v sphinx 1>/dev/null 2>/dev/null || SPHINX=0
	# Check for resize
	command -v resize2fs 1>/dev/null 2>/dev/null || RESIZER=0
	# Check for KDF auxiliary tools
	command -v tomb-kdb-pbkdf2 1>/dev/null 2>/dev/null || KDF=0
	# Check for ARGON2 KDF auxiliary tools
	command -v argon2 1>/dev/null 2>/dev/null || ARGON2=0
	# Check for Swish-E file content indexer
	command -v swish-e 1>/dev/null 2>/dev/null || SWISH=0
	# Check for QREncode for paper backups of keys
	command -v qrencode 1>/dev/null 2>/dev/null || QRENCODE=0
}

# }}} - Commandline interaction

# {{{ Key operations

# $@ is the list of all the recipient used to encrypt a tomb key
is_valid_recipients() {
	typeset -a recipients
	recipients=($@)
	trusted=(m f u w s)

	_verbose "is_valid_recipients"

	# All the keys ID must be valid (the public keys must be present in the database)
	for gpg_id in ${recipients[@]}; do
		trust="$(gpg --with-colons --batch --list-keys "$gpg_id" 2> /dev/null |
				 	awk 'BEGIN { FS=":" } /^pub/ { print $2; exit}')"
		[[ "${trust}" == "" ]] && {
			_warning "Not a valid GPG key ID: ::1 gpgid:: " $gpg_id
			return 1
		}
		[[ ${trusted[(r)$trust]} != $trust ]] && {
			_warning "The key ::1 gpgid:: is not trusted enough" $gpg_id
			return 1
		}
	done

	# At least one private key must be present
#	for gpg_id in ${recipients[@]}; do
#		gpg --with-colons --batch --list-secret-keys "$gpg_id" &> /dev/null
#		[[ $? = 0 ]] && {
#			return 0
#		}
#	done

	return 0
}

# $@ is the list of all the recipient used to encrypt a tomb key
# Print the recipient arg to be used in gpg.
_recipients_arg() {
	local arg="$1"; shift
	typeset -a recipients
	recipients=($@)

	for gpg_id in ${recipients[@]}; do
		print -R -n "$arg $gpg_id "
	done
	return 0
}

# $1 is a GPG key recipient
# Print the fingerprint of the GPG key
_gpg_fingerprint() {
	gpg --with-colons --fingerprint "$1" |
		awk 'BEGIN { FS=":" } /^fpr/ { print $10; exit }' }
_gpg_uid() {
	gpg --with-colons --list-key "$1" |
		awk 'BEGIN { FS=":" } /^uid/ { print $10; exit}' }

# helpers to retrieve data from passwd using getent
_get_username() { getent passwd ${1} | awk -F: '{print $1}' }
_get_home()     { getent passwd ${1} | awk -F: '{print $6}' }

# $1 is the encrypted key contents we are checking
is_valid_key() {
	local key="$1"		 # Unique argument is an encrypted key to test

	_verbose "is_valid_key"

	[[ -z $key ]] && key=$TOMBKEY
	[[ "$key" = "cleartext" ]] && {
		{ option_is_set --unsafe } || {
			_warning "cleartext key from stdin selected: this is unsafe."
			exitv=127 _failure "please use --unsafe if you really want to do this."
		}
		_warning "received key in cleartext from stdin (unsafe mode)"
		return 0 }

	[[ -z $key ]] && {
		_warning "is_valid_key() called without an argument."
		return 1
	}

	# If the key file is an image don't check file header
	[[ -r $TOMBKEYFILE ]] \
		&& [[ $(file $TOMBKEYFILE) =~ "JP.G" ]] \
		&& {
		_message "Key is an image, it might be valid."
		return 0 }

	[[ $KDF == 1 ]] && { ! option_is_set -g } && { option_is_set --kdf } && {
		_head="${key[(f)1]}"
		[[ $_head =~ '^_KDF_' ]] || {
			_warning "Key is missing KDF header."
			return 1
		}
	}

	[[ $key =~ "BEGIN PGP" ]] && {
		_message "Key is valid."
		return 0 }

	return 1
}

# $1 is a string containing an encrypted key
recover_key() {
	local key="${1}"	# Unique argument is an encrypted key

	_warning "Attempting key recovery."

	_head="${key[(f)1]}" # take the first line

	TOMBKEY=""		  # Reset global variable

	[[ $_head =~ "^_KDF_" ]] && TOMBKEY+="$_head\n"

	TOMBKEY+="-----BEGIN PGP MESSAGE-----\n"
	TOMBKEY+="$key\n"
	TOMBKEY+="-----END PGP MESSAGE-----\n"

	return 0
}

# Retrieve the tomb key from the file specified from the command line,
# or from stdin if -k - was selected.  Run validity checks on the
# file.	 On success, return 0 and print out the full path of the key.
# Set global variables TOMBKEY and TOMBKEYFILE.
_load_key() {
	local keyfile="$1"	  # Unique argument is an optional keyfile

	[[ -z $keyfile ]] && keyfile=$(option_value -k)
	[[ -z $keyfile ]] && {
		_failure "This operation requires a key file to be specified using the -k option." }

	if [[ $keyfile == "-" ]]; then
		_verbose "load_key reading from stdin."
		_message "Waiting for the key to be piped from stdin... "
		TOMBKEYFILE=stdin
		TOMBKEY=$(cat)
	elif [[ $keyfile == "cleartext" ]]; then
		_verbose "load_key reading SECRET from stdin"
		_message "Waiting for the key to be piped from stdin... "
		TOMBKEYFILE=cleartext
		TOMBKEY=cleartext
		TOMBSECRET=$(cat)
	else
		_verbose "load_key argument: ::1 key file::" $keyfile
		[[ -r $keyfile ]] || _failure "Key not found, specify one using -k."
		_track_stat "$keyfile"
		TOMBKEYFILE=$keyfile
		TOMBKEY="${mapfile[$TOMBKEYFILE]}"
	fi

	_verbose "load_key: ::1 key::" $TOMBKEYFILE

	[[ -z $TOMBKEY ]] && {
		# something went wrong, there is no key to load
		# this occurs especially when piping from stdin and aborted
		_failure "Key not found, specify one using -k."
	}

	is_valid_key $TOMBKEY || {
		_warning "The key seems invalid or its format is not known by this version of Tomb."
		recover_key $TOMBKEY
	}

	# Declared TOMBKEYFILE (path)
	# Declared TOMBKEY (contents)

	return 0
}

# takes two args just like get_lukskey
# prints out the decrypted content
# contains tweaks for different gpg versions
# support both symmetric and asymmetric encryption
gpg_decrypt() {
	# fix for gpg 1.4.11 where the --status-* options don't work ;^/
	local gpgver=$(gpg --version --no-permission-warning | awk '/^gpg/ {print $3}')
	local gpgpass="$1\n$TOMBKEY"
	local tmpres ret
	typeset -a gpgopt
	gpgpopt=(--batch --no-tty --passphrase-fd 0 --no-options)

	{ option_is_set -g } && {
		gpgpass="$TOMBKEY"
		gpgpopt=(--yes)

		# GPG option '--try-secret-key' exist since GPG 2.1
		{ option_is_set -R } && { autoload -U is-at-least && is-at-least "2.1" $gpgver } && {
			typeset -a recipients
			recipients=(${(s:,:)$(option_value -R)})
			{ is_valid_recipients $recipients } || {
				_failure "You set an invalid GPG ID."
			}
			gpgpopt+=(`_recipients_arg "--try-secret-key" $recipients`)
		}
	}

	[[ $gpgver == "1.4.11" ]] && {
		_verbose "GnuPG is version 1.4.11 - adopting status fix."
		TOMBSECRET=`print - "$gpgpass" | \
			gpg --decrypt ${gpgpopt[@]}`
		ret=$?
		unset gpgpass
		return $ret
	}

	_tmp_create
	tmpres=$TOMBTMP
	TOMBSECRET=`print - "$gpgpass" | \
		gpg --decrypt ${gpgpopt[@]} \
			--status-fd 2 --no-mdc-warning --no-permission-warning \
			--no-secmem-warning 2> $tmpres`
	unset gpgpass
	ret=1
	for i in ${(f)"$(cat $tmpres)"}; do
		_verbose "$i"
		[[ "$i" =~ "DECRYPTION_OKAY" ]] && ret=0;
	done
	return $ret

}


# Gets a key file and a password, prints out the decoded contents to
# be used directly by Luks as a cryptographic key
get_lukskey() {
	# $1 is the password
	_verbose "get_lukskey"

	_password="$1"


	firstline="${TOMBKEY[(f)1]}"

	# key is KDF encoded
	if [[ $firstline =~ '^_KDF_' ]]; then
		kdf_hash="${firstline[(ws:_:)2]}"
		_verbose "KDF: ::1 kdf::" "$kdf_hash"
		case "$kdf_hash" in
			"pbkdf2sha1")
				kdf_salt="${firstline[(ws:_:)3]}"
				kdf_ic="${firstline[(ws:_:)4]}"
				kdf_len="${firstline[(ws:_:)5]}"
				_message "Unlocking KDF key protection (::1 kdf::)" $kdf_hash
				_verbose "KDF salt: $kdf_salt"
				_verbose "KDF ic: $kdf_ic"
				_verbose "KDF len: $kdf_len"
				_password=$(tomb-kdb-pbkdf2 $kdf_salt $kdf_ic $kdf_len 2>/dev/null <<<$_password)
				;;

			"argon2")
				kdf_salt="${firstline[(ws:_:)3]}"
				kdf_ic="${firstline[(ws:_:)4]}"
				kdf_mem="${firstline[(ws:_:)5]}"
				_message "Unlocking KDF key protection (::1 kdf::)" $kdf_hash
				_verbose "KDF salt: $kdf_salt"
				_verbose "KDF ic: $kdf_ic"
				_verbose "KDF mem: $kdf_mem"
				_password=$(argon2 $kdf_salt -m $kdf_mem -t $kdf_ic -l 64 -r 2>/dev/null <<<$_password)
				;;

			*)
				_failure "No suitable program for KDF ::1 program::." $pbkdf_hash
				unset _password
				return 1
				;;
		esac

		# key needs to be exhumed from an image
	elif [[ -r $TOMBKEYFILE && $(file $TOMBKEYFILE) =~ "JP.G" ]]; then
		if option_is_set -g; then
			# When using a GPG key, the tomb key is buried using a steganography password
			if option_is_set --tomb-pwd; then
				_password="`option_value --tomb-pwd`"
				_verbose "tomb-pwd = ::1 tomb pass::" $_password
			else
				_password=$(ask_password "Insert password to exhume key from $imagefile")
				[[ $? != 0 ]] && {
					_warning "User aborted password dialog."
					return 1
				}
			fi
			exhume_key $TOMBKEYFILE "$_password"
			unset _password
		else
			exhume_key $TOMBKEYFILE "$_password"
		fi
	fi

	gpg_decrypt "$_password" # Save decrypted contents into $TOMBSECRET

	ret="$?"

	_verbose "get_lukskey returns ::1::" $ret
	return $ret
}

# This function asks the user for the password to use the key it tests
# it against the return code of gpg on success returns 0 and saves
# the password in the global variable $TOMBPASSWORD
ask_key_password() {
	[[ -z "$TOMBKEYFILE" ]] && {
		_failure "Internal error: ask_key_password() called before _load_key()." }

	[[ "$TOMBKEYFILE" = "cleartext" ]] && {
		_verbose "no password needed, using secret bytes from stdin"
		return 0 }

	if option_is_set -g; then
		_verbose "no password needed, using GPG key"
		get_lukskey
		return $?
	fi

	_message "A password is required to use key ::1 key::" $TOMBKEYFILE
	passok=0
	tombpass=""
	if [[ -z $1 ]]; then

		for c in 1 2 3; do
			if [[ $c == 1 ]]; then
				tombpass=$(ask_password "Insert password to: $TOMBKEYFILE")
			else
				tombpass=$(ask_password "Insert password to: $TOMBKEYFILE (attempt $c)")
			fi
			[[ $? = 0 ]] || {
				_warning "User aborted password dialog."
				return 1
			}

			get_lukskey "$tombpass"

			[[ $? = 0 ]] && {
				passok=1; _message "Password OK."
				break;
			}
		done

	else
		# if a second argument is present then the password is already known
		tombpass="$1"
		_verbose "ask_key_password with tombpass: ::1 tomb pass::" $tombpass

		# if sphinx mode is chosen, use the provided input
		# as master password to retrieve the actual password
		if option_is_set --sphx-user || option_is_set --sphx-host; then
			tombpass=$(sphinx_get_password "$tombpass")
		fi

		get_lukskey "$tombpass"

		[[ $? = 0 ]] && {
			passok=1; _message "Password OK."
		}

	fi
	[[ $passok == 1 ]] || return 1

	TOMBPASSWORD=$tombpass
	return 0
}

# call cryptsetup with arguments using the currently known secret
# echo flags eliminate newline and disable escape (BSD_ECHO)
_cryptsetup() {
	if option_is_set -q; then
		print -R -n - "$TOMBSECRET" | _sudo cryptsetup --type luks1 --key-file - ${@} 2> /dev/null
	else
		print -R -n - "$TOMBSECRET" | _sudo cryptsetup --type luks1 --key-file - ${@}
	fi
	return $?
}

# change tomb key password
change_passwd() {
	local tmpnewkey lukskey c tombpass tombpasstmp

	_check_swap	 # Ensure swap is secure, if any
	_load_key	 # Try loading key from option -k and set TOMBKEYFILE

	{ option_is_set -g } && {
		_message "Commanded to change GnuPG key for tomb key ::1 key::" $TOMBKEYFILE
	} || {
		_message "Commanded to change password for tomb key ::1 key::" $TOMBKEYFILE
	}

	_tmp_create
	tmpnewkey=$TOMBTMP

	if option_is_set --tomb-old-pwd; then
		local tomboldpwd="`option_value --tomb-old-pwd`"
		_verbose "tomb-old-pwd = ::1 old pass::" $tomboldpwd
		ask_key_password "$tomboldpwd"
	else
		ask_key_password
	fi
	[[ $? == 0 ]] || _failure "No valid password supplied."

	{ option_is_set -g } && {
		_success "Changing GnuPG key for ::1 key file::" $TOMBKEYFILE
	} || {
		_success "Changing password for ::1 key file::" $TOMBKEYFILE
	}

	# Here $TOMBSECRET contains the key material in clear

	{ option_is_set --tomb-pwd } && {
		local tombpwd="`option_value --tomb-pwd`"
		_verbose "tomb-pwd = ::1 new pass::" $tombpwd
		gen_key "$tmpnewkey" "$tombpwd"
	} || {
		gen_key "$tmpnewkey"
	}

	{ is_valid_key "${mapfile[$tmpnewkey]}" } || {
		_failure "Error: the newly generated keyfile does not seem valid." }

	# Copy the new key as the original keyfile name
	cp -f "${tmpnewkey}" $TOMBKEYFILE
	{ option_is_set -g } && {
		_success "Your GnuPG key was successfully changed"
	} || {
		_success "Your passphrase was successfully updated."
	}

	return 0
}


# takes care to encrypt a key
# honored options: --kdf  --tomb-pwd -o -g -r
gen_key() {
	# $1 key file
	# $2 the password to use; if not set ask user
	# -o is the --cipher-algo to use (string taken by GnuPG)
	local algopt="`option_value -o`"
	local algo="${algopt:-AES256}"
	local gpgpass opt
	local recipients_opt
	typeset -a gpgopt
	local sphx_host_tmp
	local sphx_user_tmp
	# here user is prompted for key password
	tombpass=""
	tombpasstmp=""

	# remove sphinx opts not to mess with initial password prompt
	option_is_set --sphx-user && {
		sphx_user_tmp="$(option_value --sphx-user)"
		unset "OPTS[--sphx-user]"
	}
	option_is_set --sphx-host && {
		sphx_host_tmp="$(option_value --sphx-host)"
		unset "OPTS[--sphx-host]"
	}

	if option_is_set -g; then
		gpgopt=(--encrypt)

		if option_is_set -r || option_is_set -R; then
			typeset -a recipients
			if option_is_set -r; then
				recipients=(${(s:,:)$(option_value -r)})
				recipients_opt="--recipient"
			else
				recipients=(${(s:,:)$(option_value -R)})
				recipients_opt="--hidden-recipient"
			fi

		    is_valid_recipients $recipients || {
				_failure "You set an invalid GPG ID."
			}

			_warning "You are going to encrypt a tomb key with ::1 nrecipients:: recipient(s)."	 ${#recipients}
			_warning "It is your responsibility to check these fingerprints."
			_warning "The fingerprints are:"
			for gpg_id in ${recipients[@]}; do
				_warning "	  `_gpg_fingerprint "$gpg_id"` :: `_gpg_uid "$gpg_id"`"
			done

			gpgopt+=(`_recipients_arg "$recipients_opt" $recipients`)
		else
			_message "No recipient specified, using default GPG key."
			gpgopt+=("--default-recipient-self")
		fi

		# Set gpg inputs and options
		gpgpass="$TOMBSECRET"
		opt=''
	else
		if [ "$2" = "" ]; then
			while true; do
				# 3 tries to write two times a matching password
				tombpass=`ask_password "Type the new password to secure your key"`
				if [[ $? != 0 ]]; then
					_failure "User aborted."
				fi
				if [ -z $tombpass ]; then
					_failure "You set empty password, which is not possible."
				fi
				tombpasstmp=$tombpass
				tombpass=`ask_password "Type the new password to secure your key (again)"`
				if [[ $? != 0 ]]; then
					_failure "User aborted."
				fi
				if [ "$tombpasstmp" = "$tombpass" ]; then
					break;
				fi
				unset tombpasstmp
				unset tombpass
			done
		else
			tombpass="$2"
			_verbose "gen_key takes tombpass from CLI argument: ::1 tomb pass::" $tombpass
		fi

		# if sphinx mode is chosen, use the provided input
		# as master password to generate the actual password
		if [[ ! -z $sphx_host_tmp ]] || [[ ! -z $sphx_user_tmp ]]; then
			OPTS[--sphx-user]=$sphx_user_tmp
			OPTS[--sphx-host]=$sphx_host_tmp
			unset sphx_user_tmp
			unset sphx_host_tmp
			tombpass=$(sphinx_set_password "$tombpass")
			if [[ $? != 0 ]]; then
				_failure "User aborted."
			fi
		fi

		header=""
		[[ $KDF == 1 ]] && {
			{ option_is_set --kdf } && {
				# KDF is a new key strenghtening technique against brute forcing
				# see: https://github.com/dyne/Tomb/issues/82
				itertime="`option_value --kdf`"
				# removing support of floating points because they can't be type checked well
				# if [[ "$itertime" != <-> ]]; then
				# 	unset tombpass
				# 	unset tombpasstmp
				# 	_warning "Wrong argument for --kdf: must be an integer number (iteration seconds)."
				# 	_failure "Depending on the speed of machines using this tomb, use 1 to 10, or more"
				# 	return 1
				# fi
				# # --kdf takes one parameter: iter time (on present machine) in seconds

				kdftype="`option_value --kdftype`"
				kdftype=${kdftype:-pbkdf2}
				case ${kdftype} in
				    pbkdf2)
					local -i microseconds
					microseconds=$(( itertime * 1000000 ))
					_success "Using KDF, iteration time: ::1 microseconds::" $microseconds
					_message "generating salt"
					pbkdf2_salt=`tomb-kdb-pbkdf2-gensalt`
					_message "calculating iterations"
					pbkdf2_iter=`tomb-kdb-pbkdf2-getiter $microseconds`
					_message "encoding the password"
					# We use a length of 64bytes = 512bits (more than needed!?)
					tombpass=`tomb-kdb-pbkdf2 $pbkdf2_salt $pbkdf2_iter 64 <<<"${tombpass}"`

					header="_KDF_pbkdf2sha1_${pbkdf2_salt}_${pbkdf2_iter}_64\n"
					;;
				    argon2)
					_success "Using KDF Argon2"
					kdfmem="`option_value --kdfmem`"
					kdfmem=${kdfmem:-18}
					_message "memory used: 2^::1 kdfmemory::" $kdfmem
					kdfsalt=`tomb-kdb-pbkdf2-gensalt`
					_message "kdf salt: ::1 kdfsalt::" $kdfsalt
					_message "kdf iterations: ::1 kdfiterations::" $itertime
					tombpass=`argon2 $kdfsalt -m $kdfmem -t $itertime -l 64 -r <<<"${tombpass}"`
					header="_KDF_argon2_${kdfsalt}_${itertime}_${kdfmem}_64\n"
					;;
				esac
			}
		}
		print $header >> "$1"

		# Set gpg inputs and options
		gpgpass="${tombpass}\n$TOMBSECRET"
		gpgopt=(--passphrase-fd 0 --symmetric --no-options)
		opt='-n'
	fi

	_tmp_create
	local tmpres=$TOMBTMP
	print $opt - "$gpgpass" \
		| gpg --openpgp --force-mdc --cipher-algo ${algo} \
			  --batch --no-tty ${gpgopt} \
			  --status-fd 2 -o - --armor 2> $tmpres >> "$1"
	unset gpgpass
	# check result of gpg operation
	for i in ${(f)"$(cat $tmpres)"}; do
		_verbose "$i"
	done

	# print -n "${tombpass}" \
		#	  | gpg --openpgp --force-mdc --cipher-algo ${algo} \
		#	  --batch --no-options --no-tty --passphrase-fd 0 --status-fd 2 \
		#	  -o - -c -a ${lukskey}

	TOMBPASSWORD="$tombpass"	# Set global variable
	unset tombpass
	unset tombpasstmp
}

# prints an array of ciphers available in gnupg (to encrypt keys)
list_gnupg_ciphers() {
	# On gpg1 and gpg2 line 10 always point to available ciphers.
	# Print those until the next section is found
	ciphers=(`gpg --version | awk '
BEGIN { ciphers=0 }
NR==11 { gsub(/,/,""); sub(/^.*:/,""); print; ciphers=1; next }
/^.*:/ { ciphers=0 }
{ if(ciphers==0) { next } else { gsub(/,/,""); print; } }
'`)
	print "${ciphers}"
	return 1
}

# Steganographic function to bury a key inside an image.
# Requires steghide(1) to be installed
bury_key() {

	_load_key	 # Try loading key from option -k and set TOMBKEY

	imagefile=$PARAM

	[[ "`file $imagefile`" =~ "JPEG" ]] || {
		_warning "Encode failed: ::1 image file:: is not a jpeg image." $imagefile
		return 1
	}

	_success "Encoding key ::1 tomb key:: inside image ::2 image file::" $TOMBKEY $imagefile
	{ option_is_set -g } && {
		_message "Using GnuPG Key ID"
	} || {
		_message "Please confirm the key password for the encoding"
	}

	# We ask the password and test if it is the same encoding the
	# base key, to insure that the same password is used for the
	# encryption and the steganography. This is a standard enforced
	# by Tomb, but it isn't strictly necessary (and having different
	# password would enhance security). Nevertheless here we prefer
	# usability.
	# However, steganography cannot be done with GPG key. Therefore,
	# if using a GPG key, we test if the user can decrypt the tomb
	# with its key and we ask for a steganography password.

	{ option_is_set --tomb-pwd } && { ! option_is_set -g } && {
		local tombpwd="`option_value --tomb-pwd`"
		_verbose "tomb-pwd = ::1 tomb pass::" $tombpwd
		ask_key_password "$tombpwd"
	} || {
		ask_key_password
	}
	[[ $? != 0 ]] && {
		_warning "Wrong password/GnuPG ID supplied."
		_failure "You shall not bury a key whose password is unknown to you." }

	if option_is_set -g && option_is_set --tomb-pwd; then
		TOMBPASSWORD="`option_value --tomb-pwd`"
		_verbose "tomb-pwd = ::1 tomb pass::" $TOMBPASSWORD
	elif option_is_set -g; then
		tombpass=""
		tombpasstmp=""
		while true; do
			# 3 tries to write two times a matching password
			tombpass=`ask_password "Type a password to bury your key"`
			if [[ $? != 0 ]]; then
				_failure "User aborted."
			fi
			if [ -z $tombpass ]; then
				_failure "You set empty password, which is not possible."
			fi
			tombpasstmp=$tombpass
			tombpass=`ask_password "Type a password to bury your key (again)"`
			if [[ $? != 0 ]]; then
				_failure "User aborted."
			fi
			if [ "$tombpasstmp" = "$tombpass" ]; then
				break;
			fi
			unset tombpasstmp
			unset tombpass
		done
		TOMBPASSWORD="$tombpass"
	fi

	# We omit armor strings since having them as constants can give
	# ground to effective attacks on steganography
	print - "$TOMBKEY" | awk '
/^-----/ {next}
/^Version/ {next}
{print $0}' \
		| steghide embed --embedfile - --coverfile ${imagefile} \
				   -p $TOMBPASSWORD -z 9 -e serpent cbc
	if [ $? != 0 ]; then
		_warning "Encoding error: steghide reports problems."
		res=1
	else
		_success "Tomb key encoded succesfully into image ::1 image file::" $imagefile
		res=0
	fi

	return $res
}

# mandatory 1st arg: the image file where key is supposed to be
# optional 2nd arg: the password to use (same as key, internal use)
# optional 3rd arg: the key where to save the result (- for stdout)
exhume_key() {
	[[ -z $1 ]] && {
		_failure "Exhume failed, no image specified" }

	local imagefile="$1"  # The image file where to look for the key
	local tombpass="$2"	  # (Optional) the password to use (internal use)
	local destkey="$3"	  # (Optional) the key file where to save the
	# result (- for stdout)
	local r=1			  # Return code (default: fail)

	# write all messages to stderr to avoid polluting stdout
	_MSG_FD_OVERRIDE=2

	# Ensure the image file is a readable JPEG
	[[ ! -r $imagefile ]] && {
		_failure "Exhume failed, image file not found: ::1 image file::" "${imagefile:-none}" }
	[[ ! $(file "$imagefile") =~ "JP.G" ]] && {
		_failure "Exhume failed: ::1 image file:: is not a jpeg image." $imagefile }

	# When a password is passed as argument then always print out
	# the exhumed key on stdout without further checks (internal use)
	[[ -n "$tombpass" ]] && {
		TOMBKEY=$(steghide extract -sf $imagefile -p $tombpass -xf -)
		[[ $? != 0 ]] && {
			_failure "Wrong password or no steganographic key found" }

		recover_key $TOMBKEY

		return 0
	}

	# Ensure we have a valid destination for the key
	[[ -z $destkey ]] && { option_is_set -k } && destkey=$(option_value -k)
	[[ -z $destkey ]] && {
		destkey="-" # No key was specified: fallback to stdout
		_message "printing exhumed key on stdout" }

	# Bail out if destination exists, unless -f (force) was passed
	[[ $destkey != "-" && -s $destkey ]] && {
		_warning "File exists: ::1 tomb key::" $destkey
		{ option_is_set -f } && {
			_warning "Use of --force selected: overwriting."
			rm -f $destkey
		} || {
			_warning "Make explicit use of --force to overwrite."
			_failure "Refusing to overwrite file. Operation aborted." }
	}

	_message "Trying to exhume a key out of image ::1 image file::" $imagefile
	{ option_is_set --tomb-pwd } && {
		tombpass=$(option_value --tomb-pwd)
		_verbose "tomb-pwd = ::1 tomb pass::" $tombpass
	} || {
		[[ -n $TOMBPASSWORD ]] && tombpass=$TOMBPASSWORD
	} || {
		tombpass=$(ask_password "Insert password to exhume key from $imagefile")
		[[ $? != 0 ]] && {
			_warning "User aborted password dialog."
			return 1
		}
	}

	# Extract the key from the image
	steghide extract -sf $imagefile -p ${tombpass} -xf $destkey
	r=$?

	# Report to the user
	[[ "$destkey" = "-" ]] && destkey="stdout"
	[[ $r == 0 ]] && {
		_success "Key succesfully exhumed to ::1 key::." $destkey
	} || {
		_warning "Nothing found in ::1 image file::" $imagefile
	}

	unset _MSG_FD_OVERRIDE

	return $r
}

# Steganographic function to transform a key into harmless-looking text
# using a cipher
# Requires cloakify to be installed
#
# mandatory 1st arg: the cipher to use
# optional 2nd arg: the output file where to save the result (none for stdout)
cloakify_key() {

	_load_key	 # Try loading key from option -k and set TOMBKEY

	local cipher="$1"    # The cipher to use
	local destfile="$2"  # (Optional) the output file where to save the
	# result (none for stdout)

	_success "Encoding key ::1 tomb key:: using cipher ::2 cipher file::" $TOMBKEYFILE $cipher

	# Ensure we have a valid destination for the cloaked key
	[[ -z $destfile ]] && {
		  destfile="/dev/stdout" # No file was specified: fallback to stdout
		  _message "printing cloaked key on stdout" }

	# Bail out if destination exists, unless -f (force) was passed
	[[ $destfile != "/dev/stdout" && -s $destfile ]] && {
		  _warning "File exists: ::1 output file::" $destfile
		  { option_is_set -f } && {
			    _warning "Use of --force selected: overwriting."
			    rm -f $destfile
		  } || {
			    _warning "Make explicit use of --force to overwrite."
			    _failure "Refusing to overwrite file. Operation aborted." }
	}

	# Cipher the key
	cloakify $TOMBKEYFILE $cipher >$destfile
	if [ $? != 0 ]; then
		_warning "Encoding error: cloakify reports problems."
		res=1
	else
		_success "Tomb key encoded succesfully"
		res=0
	fi

	return $res
}

# mandatory 1st arg: the text file where key is supposed to be
# mandatory 2nd arg: the cipher to use
# optional 3rd arg: the key where to save the result (none for stdout)
decloakify_key() {
	[[ -z $1 ]] && {
		  _failure "Uncloak failed, no text file specified" }
	[[ -z $2 ]] && {
		  _failure "Uncloak failed, no cipher file specified" }

	local textfile="$1"   # The text file where to look for the key
	local cipher="$2"     # The cipher to use
	local destkey="$3"    # (Optional) the key file where to save the
	# result (none for stdout)
	local r=1			  # Return code (default: fail)

	# write all messages to stderr to avoid polluting stdout
	_MSG_FD_OVERRIDE=2

	# Ensure the text file is readable
	[[ ! -r $textfile ]] && {
		_failure "Uncloak failed, text file not found: ::1 text file::" "${textfile:-none}" }
	# Ensure the cipher file is readable
	[[ ! -r $cipher ]] && {
		_failure "Uncloak failed, cipher file not found: ::1 cipher file::" "${cipher:-none}" }

	# Ensure we have a valid destination for the key
	[[ -z $destkey ]] && { option_is_set -k } && destkey=$(option_value -k)
	[[ -z $destkey ]] && {
		destkey="/dev/stdout" # No key was specified: fallback to stdout
		_message "printing uncloaked key on stdout" }

	# Bail out if destination exists, unless -f (force) was passed
	[[ $destkey != "/dev/stdout" && -s $destkey ]] && {
		_warning "File exists: ::1 tomb key::" $destkey
		{ option_is_set -f } && {
			_warning "Use of --force selected: overwriting."
			rm -f $destkey
		} || {
			_warning "Make explicit use of --force to overwrite."
			_failure "Refusing to overwrite file. Operation aborted." }
	}

	# Extract the key from the text file
	decloakify $textfile $cipher >$destkey
	r=$?

	# Report to the user
	[[ "$destkey" = "/dev/stdout" ]] && destkey="stdout"
	[[ $r == 0 ]] && {
		_success "Key succesfully uncloaked to ::1 key::." $destkey
	} || {
		_warning "Nothing found in ::1 text file::" $textfile
	}

	unset _MSG_FD_OVERRIDE

	return $r
}

# Produces a printable image of the key contents so a backup on paper
# can be made and hidden in books etc.
engrave_key() {

	_load_key	 # Try loading key from option -k and set TOMBKEYFILE

	local keyname=$(basename $TOMBKEYFILE)
	local pngname="$keyname.qr.png"

	_success "Rendering a printable QRCode for key: ::1 tomb key file::" $TOMBKEYFILE
	# we omit armor strings to save space
	awk '/^-----/ {next}; /^Version/ {next}; {print $0}' $TOMBKEYFILE \
		| qrencode --size 4 --level H --casesensitive -o $pngname
	[[ $? != 0 ]] && {
		_failure "QREncode reported an error." }

	_success "Operation successful:"
	# TODO: only if verbose and/or not silent
	ls -lh $pngname
	file $pngname
}

# }}} - Key handling

# {{{ Create

# Since version 1.5.3, tomb creation is a three-step process that replaces create_tomb():
#
# * dig a .tomb (the large file) using /dev/urandom (takes some minutes at least)
#
# * forge a .key (the small file) using /dev/random (good entropy needed)
#
# * lock the .tomb file with the key, binding the key to the tomb (requires dm_crypt format)

# Step one - Dig a tomb
#
# Synopsis: dig_tomb /path/to/tomb -s sizemebibytes
#
# It will create an empty file to be formatted as a loopback
# filesystem.  Initially the file is filled with random data taken
# from /dev/urandom to improve overall tomb's security and prevent
# some attacks aiming at detecting how much data is in the tomb, or
# which blocks in the filesystem contain that data.

dig_tomb() {
	# $1 arg is path to tomb

	# Require the specification of the size of the tomb (-s) in MiB
	local -i tombsize=$(option_value -s)

	_message "Commanded to dig tomb ::1 tomb path::" $tombpath

	[[ ! -z $1 ]] || _failure "Missing path to tomb"
	[[ -n "$tombsize"	]] || _failure "Size argument missing, use -s"
	[[ $tombsize == <-> ]] || _failure "Size must be an integer (mebibytes)"
	[[ $tombsize -ge 10 ]] || _failure "Tombs can't be smaller than 10 mebibytes"

	[[ -e $1 ]] && {
		_warning "A tomb exists already. I'm not digging here:"
		ls -lh $1
		return 1
	}

	_success "Creating a new tomb in ::1 tomb path::" $1
	_message "Generating ::1 tomb file:: of ::2 size::MiB" $1 $tombsize

	touch "$1"
	[[ $? = 0 ]] || {
		_warning "Error creating the tomb ::1 tomb path::" $1
		_failure "Operation aborted."
	}
	# Ensure that file permissions are safe even if interrupted
	[[ -n $SUDO_USER ]] && chown ${_UID}:${_GID} "$1"
	chmod 0600 $1
	_verbose "Data dump using ::1:: from /dev/urandom" ${DD[1]}
	${=DD} if=/dev/urandom bs=1048576 count=$tombsize of=$1
	ls -lh "$1"

	_success "Done digging ::1 tomb name::" $1
	_message "Your tomb is not yet ready, you need to forge a key and lock it:"
	_message "tomb forge ::1 tomb path::.key" $1
	_message "tomb lock ::1 tomb path:: -k ::1 tomb path::.key" $1

	return 0
}

# Step two -- Create a detached key to lock a tomb with
#
# Synopsis: forge_key [destkey|-k destkey] [-o cipher] [-r|-R gpgid]
#
# Arguments:
# -k				path to destination keyfile
# -o				Use an alternate algorithm
# -r				GPG recipients to be used
#
forge_key() {
	# can be specified both as simple argument or using -k
	local destkey="$1"
	{ option_is_set -k } && { destkey=$(option_value -k) }

	local algo="AES256"	 # Default encryption algorithm

	[[ -z "$destkey" ]] && {
		_failure "A filename needs to be specified using -k to forge a new key." }

	#	 _message "Commanded to forge key ::1 key::" $destkey

	_check_swap # Ensure the available memory is safe to use

	# Ensure GnuPG won't exit with an error before first run
	local gpghome=${GNUPGHOME:-$HOME/.gnupg}
	[[ -r $gpghome/pubring.gpg ]] || {
        mkdir -p -m 0700 $gpghome
        touch $gpghome/pubring.gpg }

	# Do not overwrite any files accidentally
	[[ -r "$destkey" ]] && {
		ls -lh $destkey
		_failure "Forging this key would overwrite an existing file. Operation aborted." }

	touch $destkey
	[[ $? == 0 ]] || {
		_warning "Cannot generate encryption key."
		_failure "Operation aborted." }
	chmod 0600 $destkey

	# Update algorithm if it was passed on the command line with -o
	{ option_is_set -o } && algopt="$(option_value -o)"
	[[ -n "$algopt" ]] && algo=$algopt

	_message "Commanded to forge key ::1 key:: with cipher algorithm ::2 algorithm::" \
			 $destkey $algo

	[[ $KDF == 1 ]] && { ! option_is_set -g } && {
		_message "Using KDF to protect the key password (`option_value --kdf` rounds)"
	}

	TOMBKEYFILE="$destkey"	  # Set global variable

	_warning "This operation takes time. Keep using this computer on other tasks."
	_warning "Once done you will be asked to choose a password for your tomb."
	_warning "To make it faster you can move the mouse around."
	_warning "If you are on a server, you can use an Entropy Generation Daemon."

	# Use /dev/urandom as the entropy source, unless --use-random is specified
	local random_source=/dev/urandom
	{ option_is_set --use-random } && random_source=/dev/random

	_verbose "Data dump using ::1:: from ::2 source::" ${DD[1]} $random_source
	TOMBSECRET=$(${=DD} bs=1 count=512 if=$random_source)
	[[ $? == 0 ]] || {
		_warning "Cannot generate encryption key."
		_failure "Operation aborted." }

	# Here the global variable TOMBSECRET contains the naked secret

	{ option_is_set -g } && {
		_success "Using GnuPG key(s) to encrypt your key: ::1 tomb key::" $TOMBKEYFILE
	} || {
		_success "Choose the password of your key: ::1 tomb key::" $TOMBKEYFILE
	}
	_message "(You can also change it later using 'tomb passwd'.)"
	# _user_file $TOMBKEYFILE

	tombname="$TOMBKEYFILE" # XXX ???
	# the gen_key() function takes care of the new key's encryption
	{ option_is_set --tomb-pwd } && {
		local tombpwd="`option_value --tomb-pwd`"
		_verbose "tomb-pwd = ::1 new pass::" $tombpwd
		gen_key $TOMBKEYFILE "$tombpwd"
	} || {
		gen_key $TOMBKEYFILE
	}

	# load the key contents (set global variable)
	TOMBKEY="${mapfile[$TOMBKEYFILE]}"

	# this does a check on the file header
	is_valid_key $TOMBKEY || {
		_warning "The key does not seem to be valid."
		_warning "Dumping contents to screen:"
		print "${mapfile[$TOMBKEY]}"
		_warning "--"
		rm -f ${TOMBKEYFILE}
		_failure "Operation aborted."
	}

	[[ -n $SUDO_USER ]] && chown ${_UID}:${_GID} "$TOMBKEYFILE"
	_message "Done forging ::1 key file::" $TOMBKEYFILE
	_success "Your key is ready:"
	ls -lh $TOMBKEYFILE
}

# Step three -- Lock tomb
#
# Synopsis: tomb_lock file.tomb file.tomb.key [-o cipher] [-r gpgid]
#
# Lock the given tomb with the given key file, in fact formatting the
# loopback volume as a LUKS device.
# Default cipher 'aes-xts-plain64'can be overridden with -o
lock_tomb_with_key() {
	# old default was aes-cbc-essiv:sha256
	# Override with -o
	# for more alternatives refer to cryptsetup(8)
	local cipher="aes-xts-plain64"

	local tombpath="$1"		 # First argument is the path to the tomb

	[[ -n $tombpath ]] || {
		_warning "No tomb specified for locking."
		_warning "Usage: tomb lock file.tomb -k file.tomb.key"
		return 1
	}


	is_valid_tomb $tombpath

	_message "Commanded to lock tomb ::1 tomb file::" $TOMBFILE

	[[ -f $TOMBPATH ]] || {
		_failure "There is no tomb here. You have to dig it first." }

	_verbose "Tomb found: ::1 tomb path::" $TOMBPATH

	local filesystem=ext4
    option_is_set --filesystem && {
		filesystem=`option_value --filesystem`
		local tombsize=`stat --format '%s' $tombpath`
		case $filesystem in
			ext3|ext4) ;;
			ext3maxinodes|ext4maxinodes) ;;
			btrfs)
				if [[ $tombsize -lt 49283072 ]]; then
					_failure "Filesystem ::1 filesystem:: not supported on tombs smaller than 47MB." \
						$filesystem
				fi
				;;
			btrfsmixedmode)
				if [[ $tombsize -lt 18874368 ]]; then
					_failure "Filesystem ::1 filesystem:: not supported on tombs smaller than 18MB." \
						$filesystem
				fi
				;;
			*)
				_failure "Filesystem not supported: ::1 filesystem::" $filesystem
				return 1
				;;
		esac
		_success "Selected filesystem type $filesystem."
	}

	lo_mount "$TOMBPATH"

	_verbose "Loop mounted on ::1 mount point::" $TOMBLOOP

	_message "Checking if the tomb is empty (we never step on somebody else's bones)."
	_sudo cryptsetup isLuks ${TOMBLOOP}
	if [ $? = 0 ]; then
		# is it a LUKS encrypted nest? then bail out and avoid reformatting it
		_warning "The tomb was already locked with another key."
		_failure "Operation aborted. I cannot lock an already locked tomb. Go dig a new one."
	else
		_message "Fine, this tomb seems empty."
	fi

	_load_key	 # Try loading key from option -k and set TOMBKEYFILE

	# the encryption cipher for a tomb can be set when locking using -c
	{ option_is_set -o } && algopt="$(option_value -o)"
	[[ -n "$algopt" ]] && cipher=$algopt
	_message "Locking using cipher: ::1 cipher::" $cipher

	# get the pass from the user and check it
	if option_is_set --tomb-pwd; then
		tomb_pwd="`option_value --tomb-pwd`"
		_verbose "tomb-pwd = ::1 tomb pass::" $tomb_pwd
		ask_key_password "$tomb_pwd"
	else
		ask_key_password
	fi
	[[ $? == 0 ]] || _failure "No valid password supplied."

	_success "Locking ::1 tomb file:: with ::2 tomb key file::" $TOMBFILE $TOMBKEYFILE

	_message "Formatting Luks mapped device."
	_cryptsetup --batch-mode \
				--cipher ${cipher} --hash sha512 --key-size 512 --key-slot 0 \
				luksFormat ${TOMBLOOP}
	[[ $? == 0 ]] || {
		_warning "cryptsetup luksFormat returned an error."
		_failure "Operation aborted." }

	_cryptsetup --cipher ${cipher} --hash sha512 luksOpen ${TOMBLOOP} tomb.tmp
	[[ $? == 0 ]] || {
		_warning "cryptsetup luksOpen returned an error."
		_failure "Operation aborted." }

	_message "Formatting your Tomb with $filesystem filesystem."
	case $filesystem in
		ext3|ext4)
			_sudo mkfs.${filesystem} -q -F -j -L $TOMBNAME /dev/mapper/tomb.tmp
			;;
		ext3maxinodes|ext4maxinodes) # TODO: cover with test
			filesystem=${filesystem:0:4}
			_sudo mkfs.${filesystem} -q -F -j -i 1024 -b 1024 -L $TOMBNAME /dev/mapper/tomb.tmp
			;;
		btrfs) # TODO: cover with test
			_sudo mkfs.${filesystem} -q -L $TOMBNAME /dev/mapper/tomb.tmp
			;;
		btrfsmixedmode) # TODO: cover with test
			filesystem=${filesystem:0:5}
			_sudo mkfs.${filesystem} -q -M -L $TOMBNAME /dev/mapper/tomb.tmp
			;;
	esac

	[[ $? == 0 ]] || {
		_warning "Tomb format returned an error."
		_sudo cryptsetup luksClose tomb.tmp
		_failure "Your tomb ::1 tomb file:: may be corrupted." $TOMBFILE }

	# Sync
	_sudo cryptsetup luksClose tomb.tmp

	_message "Done locking ::1 tomb name:: using Luks dm-crypt ::2 cipher::" $TOMBNAME $cipher
	_success "Your tomb is ready in ::1 tomb path:: and secured with key ::2 tomb key::" \
			 $TOMBPATH $TOMBKEYFILE
	return 0
}

# This function changes the key that locks a tomb
change_tomb_key() {
	local tombkey="$1"		# Path to the tomb's key file
	local tombpath="$2"		# Path to the tomb

	_message "Commanded to reset key for tomb ::1 tomb path::" $tombpath

	[[ -z "$tombpath" ]] && {
		_warning "Command 'setkey' needs two arguments: the old key file and the tomb."
		_warning "I.e:	tomb -k new.tomb.key old.tomb.key secret.tomb"
		_failure "Execution aborted."
	}

	_check_swap

	is_valid_tomb $tombpath

	lo_mount "$TOMBPATH"

	_sudo cryptsetup isLuks ${TOMBLOOP}
	# is it a LUKS encrypted nest? we check one more time
	[[ $? == 0 ]] || {
		_failure "Not a valid LUKS encrypted volume: ::1 volume::" $TOMBPATH }

	_load_key $tombkey	  # Try loading given key and set TOMBKEY


	# TOMBKEYFILE
	local oldkey=$TOMBKEY
	local oldkeyfile=$TOMBKEYFILE

	# we have everything, prepare to mount
	_success "Changing lock on tomb ::1 tomb name::" $TOMBNAME
	_message "Old key: ::1 old key::" $oldkeyfile

	# load the old key
	if option_is_set --tomb-old-pwd; then
		tomb_old_pwd="`option_value --tomb-old-pwd`"
		_verbose "tomb-old-pwd = ::1 old pass::" $tomb_old_pwd
		ask_key_password "$tomb_old_pwd"
	else
		ask_key_password
	fi
	[[ $? == 0 ]] || {
		_failure "No valid password supplied for the old key." }
	old_secret=$TOMBSECRET

	# luksOpen the tomb (not really mounting, just on the loopback)
	print -R -n - "$old_secret" | _sudo cryptsetup --key-file - \
										luksOpen ${TOMBLOOP} ${TOMBMAPPER}
	[[ $? == 0 ]] || _failure "Unexpected error in luksOpen."

	_load_key # Try loading new key from option -k and set TOMBKEYFILE

	_message "New key: ::1 key file::" $TOMBKEYFILE

	if option_is_set --tomb-pwd; then
		tomb_new_pwd="`option_value --tomb-pwd`"
		_verbose "tomb-pwd = ::1 tomb pass::" $tomb_new_pwd
		ask_key_password "$tomb_new_pwd"
	else
		ask_key_password
	fi
	[[ $? == 0 ]] || {
		_failure "No valid password supplied for the new key." }

	_tmp_create
	tmpnewkey=$TOMBTMP
	print -R -n - "$TOMBSECRET" >> $tmpnewkey

	print -R -n - "$old_secret" | _sudo cryptsetup --key-file - \
										luksChangeKey "$TOMBLOOP" "$tmpnewkey"

	[[ $? == 0 ]] || _failure "Unexpected error in luksChangeKey."

	_sudo cryptsetup luksClose "${TOMBMAPPER}" || _failure "Unexpected error in luksClose."

	_success "Successfully changed key for tomb: ::1 tomb file::" $TOMBFILE
	_message "The new key is: ::1 new key::" $TOMBKEYFILE

	return 0
}

# }}} - Creation

# {{{ Open

_update_control_file() {
	# make sure a control file exists, gives it user ownership
	# and replaces it with new contents
	# stdin = contents
	# $1 = path to control file
	# $2 = contents
	[[ -z $2 ]] && return 1
	_sudo touch "$1"
	_sudo chown ${_UID}:${_GID} "$1"
	print "$2" > "$1"
	_verbose "updated control file $1 = $2"
}

_detect_filesystem() {
	local device=$1
	_verbose "detecting filesystem of ::1 device::" $device
	print "`lsblk -in -o FSTYPE $device`"
}

# $1 = tombfile $2(optional) = mountpoint
mount_tomb() {
	[[ -n "$1" ]] || _failure "No tomb name specified for opening."

	_message "Commanded to open tomb ::1 tomb name::" $1

	_check_swap

	is_valid_tomb $1

	_track_stat "$TOMBPATH"

	_load_key # Try loading new key from option -k and set TOMBKEYFILE

	tombmount="$2"
	[[ -z "$tombmount" ]] && {
		tombmount="/media/$TOMBNAME"
		[[ -d /media ]] || { # no /media found, adopting /run/media/$USER (udisks2 compat)
			tombmount="/run/media/$_USER/$TOMBNAME"
		}
		_message "Mountpoint not specified, using default: ::1 mount point::" "$tombmount"
	}

	_success "Opening ::1 tomb file:: on ::2 mount point::" $TOMBNAME "$tombmount"

	# check if the mountpoint is already used
	mounted_tombs=(`list_tomb_mounts`)
	for t in ${mounted_tombs}; do
		usedmount=${t[(ws:;:)2]}
		[[ "$usedmount" == "$tombmount" ]] &&
			_failure "Mountpoint already in use: ::1 mount point::" "$tombmount"
	done

	lo_mount "$TOMBPATH"

	_sudo cryptsetup isLuks ${TOMBLOOP} || {
		# is it a LUKS encrypted nest? see cryptsetup(1)
		_failure "::1 tomb file:: is not a valid Luks encrypted storage file." $TOMBFILE }

	_message "This tomb is a valid LUKS encrypted device."

	luksdump="`_sudo cryptsetup luksDump ${TOMBLOOP}`"
	tombdump=(`print $luksdump | awk '
		/^Cipher name/ {print $3}
		/^Cipher mode/ {print $3}
		/^Hash spec/   {print $3}'`)
	_message "Cipher is \"::1 cipher::\" mode \"::2 mode::\" hash \"::3 hash::\"" $tombdump[1] $tombdump[2] $tombdump[3]

	slotwarn=`print $luksdump | awk '
		BEGIN { zero=0 }
		/^Key slot 0/ { zero=1 }
		/^Key slot.*ENABLED/ { if(zero==1) print "WARN" }'`
	[[ "$slotwarn" == "WARN" ]] && {
		_warning "Multiple key slots are enabled on this tomb. Beware: there can be a backdoor." }

	_verbose "Tomb key: ::1 key file::" $TOMBKEYFILE

	# take the name only, strip extensions
	_verbose "Tomb name: ::1 tomb name:: (to be engraved)" $TOMBNAME

	{ option_is_set --tomb-pwd } && { ! option_is_set -g } && {
		tomb_pwd="`option_value --tomb-pwd`"
		_verbose "tomb-pwd = ::1 tomb pass::" $tomb_pwd
		ask_key_password "$tomb_pwd"
	} || {
		ask_key_password
	}
	[[ $? == 0 ]] || _failure "No valid password supplied."

	_cryptsetup luksOpen ${TOMBLOOP} ${TOMBMAPPER}
	[[ $? = 0 ]] || {
		_failure "Failure mounting the encrypted file." }

	# preserve the loopdev after exit
	lo_preserve "$TOMBLOOP"

	# array: [ cipher, keysize, loopdevice ]
	tombstat=(`_sudo cryptsetup status ${TOMBMAPPER} | awk '
	/cipher:/  {print $2}
	/keysize:/ {print $2}
	/device:/  {print $2}'`)
	_success "Success unlocking tomb ::1 tomb name::" $TOMBNAME
	_verbose "Key size is ::1 size:: for cipher ::2 cipher::" $tombstat[2] $tombstat[1]

	filesystem=`_detect_filesystem /dev/mapper/${TOMBMAPPER}`
	_message "Filesystem detected: ::1 filesystem::" $filesystem
	# TODO: check if FS is supported, else close luks and loop

	_verbose "Tomb engraved as ::1 tomb name::" $TOMBNAME

	if option_value_contains -o ro; then
		_message "Skipping filesystem checks in read-only"
	else
		_message "Checking filesystem via ::1::" $tombstat[3]
		case $filesystem in
			ext3|ext4)
				if option_is_set -q; then
					_sudo fsck -p -C0 /dev/mapper/${TOMBMAPPER} > /dev/null
				else
					_sudo fsck -p -C0 /dev/mapper/${TOMBMAPPER}
				fi
				# TODO:     btrfs filesystem label [<device>|<mount_point>] [<newlabel>]
				_sudo tune2fs -L $TOMBNAME /dev/mapper/${TOMBMAPPER} > /dev/null
				;;
			btrfs)
				_sudo btrfs check /dev/mapper/${TOMBMAPPER}
				_sudo btrfs filesystem label /dev/mapper/${TOMBMAPPER} ${TOMBNAME}
				;;
		esac
	fi

	# we need root from here on
	_sudo mkdir -p "$tombmount"

	# Default mount options are overridden with the -o switch
	{ option_is_set -o } && {
		local oldmountopts=$MOUNTOPTS
		MOUNTOPTS="$(option_value -o)" }
	# TODO: safety check MOUNTOPTS
	# safe_mount_options &&
	_sudo mount -o $MOUNTOPTS /dev/mapper/${TOMBMAPPER} "${tombmount}"
	# Clean up if the mount failed
	[[ $? == 0 ]] || {
		_warning "Error mounting ::1 mapper:: on ::2 tombmount::" $TOMBMAPPER "$tombmount"
		[[ $oldmountopts != $MOUNTOPTS ]] && \
			_warning "Are mount options '::1 mount options::' valid?" $MOUNTOPTS
		# TODO: move cleanup to _endgame()
		[[ -d "$tombmount" ]] && _sudo rmdir "$tombmount"
		[[ -e /dev/mapper/$TOMBMAPPER ]] && _sudo cryptsetup luksClose $TOMBMAPPER
		# The loop is taken care of in _endgame()
		_failure "Cannot mount ::1 tomb name::" $TOMBNAME
	}

	_success "Success opening ::1 tomb file:: on ::2 mount point::" $TOMBFILE "$tombmount"
	local tombtty tombhost tombuid tombuser

	# print out when it was opened the last time, by whom and where
	[[ -r "${tombmount}/.last" ]] && {
		tombsince=$(cat "${tombmount}/.last")
		tombsince=$(date --date=@$tombsince +%c)
		tombtty=$(cat "${tombmount}/.tty")
		tombhost=$(cat "${tombmount}/.host")
		tomblast=$(cat "${tombmount}/.last")
		tombuid=$(cat "${tombmount}/.uid" | tr -d ' ')

		tombuser=`_get_username $tombuid`

		_message "Last visit by ::1 user::(::2 tomb build::) from ::3 tty:: on ::4 host::" $tombuser $tombuid $tombtty $tombhost
		_message "on date ::1 date::" $tombsince
		[[ -r "${tombmount}"/.cleanexit ]] || _message "the door was slammed or shutdown called before umount."
	}

	# write down the UID and TTY that opened the tomb
	option_value_contains -o ro || {
		_update_control_file "${tombmount}/.uid" $_UID
		_update_control_file "${tombmount}/.tty" $_TTY
		# also the hostname
		if command -v hostname >/dev/null; then
			_update_control_file "${tombmount}/.host" `hostname`
		elif [[ -r /etc/hostname ]]; then
			_update_control_file "${tombmount}/.host" $(cat /etc/hostname)
		else
			_update_control_file "${tombmount}/.host" localhost
		fi
		# and the "last time opened" information
		# in minutes since 1970, this is printed at next open
		_update_control_file "${tombmount}/.last" `date +%s`
		# human readable: date --date=@"`cat .last`" +%c
	}
	# process bind-hooks (mount -o bind of directories)
	# and exec-hooks (execute on open)
	option_is_set -n || {
		exec_safe_bind_hooks "${tombmount}"
		exec_safe_func_hooks open "${tombmount}"
	}

	# Changes ownership to current user. This facilitates a lot
	# usability by single users. If a Tomb is opened read-only or it
	# is "multiuser" and contains ACL "by convention" using UNIX
	# ownership that needs to be preserved, then this behavior can be
	# deactivated using -p
	local dochown=true
	option_value_contains -o ro && dochown=false
	option_is_set -p            && dochown=false
	$dochown && _sudo chown -R ${_UID}:${_GID} "${tombmount}"

	return 0
}

## HOOKS EXECUTION
#
# Execution of code inside a tomb may present a security risk, e.g.,
# if the tomb is shared or compromised, an attacker could embed
# malicious code.  When in doubt, open the tomb with the -n switch in
# order to skip this feature and verify the files mount-hooks and
# bind-hooks inside the tomb yourself before letting them run.

# Mount files and directories from the tomb to the current user's HOME.
#
# Synopsis: exec_safe_bind_hooks /path/to/mounted/tomb
#
# This can be a security risk if you share tombs with untrusted people.
# In that case, use the -n switch to turn off this feature.
exec_safe_bind_hooks() {
	local mnt="$1"	 # First argument is the mount point of the tomb

	# Default mount options are overridden with the -o switch
	[[ -n ${(k)OPTS[-o]} ]] && MOUNTOPTS=${OPTS[-o]}

	# No HOME set? Note: this should never happen again.
	[[ -z $HOME ]] && {
		_warning "How pitiful!	A tomb, and no HOME."
		return 1 }

	[[ -z $mnt || ! -d $mnt ]] && {
		_warning "Cannot exec bind hooks without a mounted tomb."
		return 1 }

	[[ -r "$mnt/bind-hooks" ]] || {
		_verbose "bind-hooks not found in ::1 mount point::" $mnt
		return 0 }

	typeset -Al maps		# Maps of files and directories to mount
	typeset -al mounted		# Track already mounted files and directories

	# better parsing for bind hooks checks for two separated words on
	# each line, using zsh word separator array subscript
	_bindhooks="${mapfile[${mnt}/bind-hooks]}"
	for h in ${(f)_bindhooks}; do
		h=${h//\\ /__ESC_SPACE__}
		s="${h[(w)1]}"
		d="${h[(w)2]}"
		s=${s//__ESC_SPACE__/ }
		d=${d//__ESC_SPACE__/ }
		[[ -z $s ]] && { _warning "bind-hooks file is broken"; return 1 }
		[[ -z $d ]] && { _warning "bind-hooks file is broken"; return 1 }
		maps+=($s $d)
		_verbose "bind-hook found: $s -> $d"
	done
	unset _bindhooks

	for dir in ${(k)maps}; do
		[[ "${dir[1]}" == "/" || "${dir[1,2]}" == ".." ]] && {
			_warning "bind-hooks map format: local/to/tomb local/to/\$HOME"
			continue }

		[[ "${${maps[$dir]}[1]}" == "/" || "${${maps[$dir]}[1,2]}" == ".." ]] && {
			_warning "bind-hooks map format: local/to/tomb local/to/\$HOME.	 Rolling back"
			for dir in ${mounted}; do _sudo umount $dir; done
			return 0 }

		if [[ ! -r "$HOME/${maps[$dir]}" ]]; then
			_warning "bind-hook target not existent, skipping ::1 home::/::2 subdir::" $HOME ${maps[$dir]}
		elif [[ ! -r "$mnt/$dir" ]]; then
			_warning "bind-hook source not found in tomb, skipping ::1 mount point::/::2 subdir::" $mnt $dir
		else
			_sudo mount -o bind,$MOUNTOPTS $mnt/$dir $HOME/${maps[$dir]} \
				&& mounted+=("$HOME/${maps[$dir]}")
		fi
	done
}

# Execute automated actions configured in the tomb.
#
# Synopsis: exec_safe_func_hooks /path/to/mounted/tomb
#
# If an executable file named 'exec-hooks' is found inside the tomb,
# run it as a user.	 This might need a dialog for security on what is
# being run, however we expect you know well what is inside your tomb.
# If you're mounting an untrusted tomb, be safe and use the -n switch
# to verify what it would run if you let it.  This feature opens the
# possibility to make encrypted executables.
exec_safe_func_hooks() {
	local mnt
	mnt="$2"
	# Only run if post-hooks has the executable bit set
	[[ -x $mnt/exec-hooks ]] && {
		_success "Exec hook: ::1 exec hook:: ::2 action::" \
				 "${mnt}/exec-hooks" "$1"
		# here call two actions: open or close. Synopsis:
		# $1	 $2			  $3		  $4		  $5
		# open	"$tombmount"
		# close "$tombmount" "$tombname" "$tombloop" "$TOMBMAPPER"
		$mnt/exec-hooks "$1" "$2" "$3" "$4" "$5"
		return $?
	}
	return 0
}

# }}} - Tomb open

# {{{ List

# list all tombs mounted in a readable format
# $1 is optional, to specify a tomb
list_tombs() {

	local tombname tombmount tombfs tombfsopts tombloop
	local ts tombtot tombused tombavail tombpercent tombp tombsince
	local tombtty tombhost tombuid tombuser
	# list all open tombs
	mounted_tombs=(`list_tomb_mounts $1`)
	[[ ${#mounted_tombs} == 0 ]] && {
		_failure "I can't see any ::1 status:: tomb, may they all rest in peace." ${1:-open} }

	for t in ${mounted_tombs}; do
		mapper=`basename ${t[(ws:;:)1]}`
		tombname=${t[(ws:;:)5]}
		tombmount="${t[(ws:;:)2]}"
		tombfs=${t[(ws:;:)3]}
		tombfsopts=${t[(ws:;:)4]}
		tombloop=${mapper[(ws:.:)4]}

		# calculate tomb size
		ts=`df -hP /dev/mapper/$mapper |
awk "/mapper/"' { print $2 ";" $3 ";" $4 ";" $5 }'`
		tombtot=${ts[(ws:;:)1]}
		tombused=${ts[(ws:;:)2]}
		tombavail=${ts[(ws:;:)3]}
		tombpercent=${ts[(ws:;:)4]}
		tombp=${tombpercent%%%}

		# obsolete way to get the last open date from /dev/mapper
		# which doesn't work when tomb filename contain dots
		# tombsince=`date --date=@${mapper[(ws:.:)3]} +%c`

		# find out who opens it from where
		[[ -r "${tombmount}/.tty" ]] && {
			tombsince=$(cat "${tombmount}/.last")
			tombsince=$(date --date=@$tombsince +%c)
			tombtty=$(cat "${tombmount}/.tty")
			tombhost=$(cat "${tombmount}/.host")
			tombuid=$(cat "${tombmount}/.uid" | tr -d ' ')

			tombuser=`_get_username $tombuid`
		}

		{ option_is_set --get-mountpoint } && { print "$tombmount"; continue }

		_message "::1 tombname:: open on ::2 tombmount:: using ::3 tombfsopts::" \
				 $tombname "$tombmount" $tombfsopts

		_verbose "::1 tombname:: /dev/::2 tombloop:: device mounted (detach with losetup -d)" $tombname $tombloop

		_message "::1 tombname:: open since ::2 tombsince::" $tombname $tombsince

		[[ -z "$tombtty" ]] || {
			_message "::1 tombname:: open by ::2 tombuser:: from ::3 tombtty:: on ::4 tombhost::" \
					 $tombname $tombuser $tombtty $tombhost
		}

		_message "::1 tombname:: size ::2 tombtot:: of which ::3 tombused:: (::5 tombpercent::%) is used: ::4 tombavail:: free " \
				 $tombname $tombtot $tombused $tombavail $tombpercent

		[[ ${tombp} -ge 90 ]] && {
			_warning "::1 tombname:: warning: your tomb is almost full!" $tombname
		}

		# Now check hooks
		mounted_hooks=(`list_tomb_binds $tombname "$tombmount"`)
		for h in ${mounted_hooks}; do
			_message "::1 tombname:: hooks ::2 hookdest::" \
					 $tombname ${h[(ws:;:)2]}
		done
	done
	return 0
}


# Print out an array of mounted tombs (internal use)
# Format is semi-colon separated list of attributes
# if 1st arg is supplied, then list only that tomb
#
# String positions in the semicolon separated array:
#
# 1. full mapper path
#
# 2. mountpoint
#
# 3. filesystem type
#
# 4. mount options
#
# 5. tomb name
list_tomb_mounts() {
	[[ -z "$1" ]] && {
		# list all open tombs
		_sudo findmnt -rvo SOURCE,TARGET,FSTYPE,OPTIONS,LABEL \
			| awk '
BEGIN { main="" }
/^\/dev\/mapper\/tomb/ {
  if(main==$1) next;
  print $1 ";" $2 ";" $3 ";(" $4 ");[" $5 "]"
  main=$1
}
'
	} || {
		# list a specific tomb
		# add square parens if not present (detection)
		local tname
		if [[ "${1[1]}" = "[" ]]; then tname="$1"
		else tname="[$1]"; fi
		_sudo findmnt -rvo SOURCE,TARGET,FSTYPE,OPTIONS,LABEL \
			| awk -vtomb="$tname" '
BEGIN { main="" }
/^\/dev\/mapper\/tomb/ {
  if("["$5"]"!=tomb) next;
  if(main==$1) next;
  print $1 ";" $2 ";" $3 ";(" $4 ");[" $5 "]"
  main=$1
}
'
	}
}

# list_tomb_binds
# print out an array of mounted bind hooks (internal use)
# format is semi-colon separated list of attributes
# needs two arguments: name of tomb whose hooks belong
#					   mount tomb
list_tomb_binds() {
	[[ -z "$2" ]] && {
		_failure "Internal error: list_tomb_binds called without argument." }

	# much simpler than the crazy from before
	# in fact, the second parameter is now redundant
	# as we only need the tomb name

	# note that this code assumes that the tomb name is provided in square brackets

	_sudo findmnt -ro SOURCE,TARGET,FSTYPE,OPTIONS,LABEL \
		| grep -F "/dev/mapper/tomb" \
		| awk -vpattern="$1" '
BEGIN { }
{
  if("["$5"]"!=pattern) next;
  if(index($1,"[")==0) next;
  gsub("[[][^]]*[]]","",$1);
  print $1 ";" $2 ";" $3 ";(" $4 ");[" $5 "]"
}
'
}

# }}} - Tomb list

# {{{ Index and search

# index files in all tombs for search
# $1 is optional, to specify a tomb
index_tombs() {
	{ command -v updatedb 1>/dev/null 2>/dev/null } || {
		_failure "Cannot index tombs on this system: updatedb (mlocate/plocate) not installed." }

	updatedbver=`updatedb --version | grep '^updatedb'`
	[[ "$updatedbver" =~ "GNU findutils" ]] && {
		_warning "Cannot use GNU findutils for index/search commands." }
	[[ "$updatedbver" =~ "locate" ]] || {
		_failure "Index command needs 'mlocate/plocate' to be installed." }

	_verbose "$updatedbver"

	mounted_tombs=(`list_tomb_mounts $1`)
	[[ ${#mounted_tombs} == 0 ]] && {
		# Considering one tomb
		[[ -n "$1" ]] && {
			_failure "There seems to be no open tomb engraved as [::1::]" $1 }
		# Or more
		_failure "I can't see any open tomb, may they all rest in peace." }

	_success "Creating and updating search indexes."

	# start the LibreOffice document converter if installed
	{ command -v unoconv 1>/dev/null 2>/dev/null } && {
		unoconv -l 2>/dev/null &
		_verbose "unoconv listener launched."
		sleep 1 }

	for t in ${mounted_tombs}; do
		mapper=`basename ${t[(ws:;:)1]}`
		tombname=${t[(ws:;:)5]}
		tombmount="${t[(ws:;:)2]}"
		[[ -r "${tombmount}/.noindex" ]] && {
			_message "Skipping ::1 tomb name:: (.noindex found)." $tombname
			continue }
		_message "Indexing ::1 tomb name:: filenames..." $tombname
		updatedb -l 0 -o "${tombmount}/.updatedb" -U "${tombmount}"

		# here we use swish to index file contents
		[[ $SWISH == 1 ]] && {
			_message "Indexing ::1 tomb name:: contents..." $tombname
			rm -f "${tombmount}/.swishrc"
			_message "Generating a new swish-e configuration file: ::1 swish conf::" "${tombmount}/.swishrc"
			cat <<EOF > "${tombmount}/.swishrc"
# index directives
DefaultContents TXT*
IndexDir "$tombmount"
IndexFile "$tombmount/.swish"
# exclude images
FileRules filename regex /\.jp.?g/i
FileRules filename regex /\.png/i
FileRules filename regex /\.gif/i
FileRules filename regex /\.tiff/i
FileRules filename regex /\.svg/i
FileRules filename regex /\.xcf/i
FileRules filename regex /\.eps/i
FileRules filename regex /\.ttf/i
# exclude audio
FileRules filename regex /\.mp3/i
FileRules filename regex /\.ogg/i
FileRules filename regex /\.wav/i
FileRules filename regex /\.mod/i
FileRules filename regex /\.xm/i
# exclude video
FileRules filename regex /\.mp4/i
FileRules filename regex /\.avi/i
FileRules filename regex /\.ogv/i
FileRules filename regex /\.ogm/i
FileRules filename regex /\.mkv/i
FileRules filename regex /\.mov/i
FileRules filename regex /\.flv/i
FileRules filename regex /\.webm/i
# exclude system
FileRules filename is ok
FileRules filename is lock
FileRules filename is control
FileRules filename is status
FileRules filename is proc
FileRules filename is sys
FileRules filename is supervise
FileRules filename regex /\.asc$/i
FileRules filename regex /\.gpg$/i
# pdf and postscript
FileFilter .pdf pdftotext "'%p' -"
FileFilter .ps	ps2txt "'%p' -"
# compressed files
FileFilterMatch lesspipe "%p" /\.tgz$/i
FileFilterMatch lesspipe "%p" /\.zip$/i
FileFilterMatch lesspipe "%p" /\.gz$/i
FileFilterMatch lesspipe "%p" /\.bz2$/i
FileFilterMatch lesspipe "%p" /\.Z$/
# spreadsheets
FileFilterMatch unoconv "-d spreadsheet -f csv --stdout %P" /\.xls.*/i
FileFilterMatch unoconv "-d spreadsheet -f csv --stdout %P" /\.xlt.*/i
FileFilter .ods unoconv "-d spreadsheet -f csv --stdout %P"
FileFilter .ots unoconv "-d spreadsheet -f csv --stdout %P"
FileFilter .dbf unoconv "-d spreadsheet -f csv --stdout %P"
FileFilter .dif unoconv "-d spreadsheet -f csv --stdout %P"
FileFilter .uos unoconv "-d spreadsheet -f csv --stdout %P"
FileFilter .sxc unoconv "-d spreadsheet -f csv --stdout %P"
# word documents
FileFilterMatch unoconv "-d document -f txt --stdout %P" /\.doc.*/i
FileFilterMatch unoconv "-d document -f txt --stdout %P" /\.odt.*/i
FileFilterMatch unoconv "-d document -f txt --stdout %P" /\.rtf.*/i
FileFilterMatch unoconv "-d document -f txt --stdout %P" /\.tex$/i
# native html support
IndexContents HTML* .htm .html .shtml
IndexContents XML* .xml
EOF

			swish-e -c "${tombmount}/.swishrc" -S fs -v3
		}
		_message "Search index updated."
	done
	return 0
}

search_tombs() {
	{ command -v locate 1>/dev/null 2>/dev/null } || {
		_failure "Cannot index tombs on this system: updatedb (mlocate/plocate) not installed." }

	updatedbver=`updatedb --version | grep '^updatedb'`
	[[ "$updatedbver" =~ "GNU findutils" ]] && {
		_warning "Cannot use GNU findutils for index/search commands." }
	[[ "$updatedbver" =~ "locate" ]] || {
		_failure "Index command needs 'mlocate/plocate' to be installed." }

	_verbose "$updatedbver"

	# list all open tombs
	mounted_tombs=(`list_tomb_mounts`)
	[[ ${#mounted_tombs} == 0 ]] && {
		_failure "I can't see any open tomb, may they all rest in peace." }

	_success "Searching for: ::1::" ${(f)@}
	for t in ${mounted_tombs}; do
		_verbose "Checking for index: ::1::" ${t}
		mapper=`basename ${t[(ws:;:)1]}`
		tombname=${t[(ws:;:)5]}
		tombmount="${t[(ws:;:)2]}"
		[[ -r "${tombmount}/.updatedb" ]] && {
			# Use mlocate/plocate to search hits on filenames
			_message "Searching filenames in tomb ::1 tomb name::" $tombname
			locate -d "${tombmount}/.updatedb" -e -i "${(f)@}"
			_message "Matches found: ::1 matches::" \
					 $(locate -d "${tombmount}/.updatedb" -e -i -c ${(f)@})

			# Use swish-e to search over contents
			[[ $SWISH == 1 && -r "$tombmount/.swish" ]] && {
				_message "Searching contents in tomb ::1 tomb name::" $tombname
				swish-e -w ${@} -f "$tombmount/.swish" -H0 }
		} || {
			_warning "Skipping tomb ::1 tomb name::: not indexed." $tombname
			_warning "Run 'tomb index' to create indexes." }
	done
	_message "Search completed."
	return 0
}

# }}} - Index and search

# {{{ Resize

# resize tomb file size
resize_tomb() {
	local tombpath="$1"	   # First argument is the path to the tomb

	_message "Commanded to resize tomb ::1 tomb name:: to ::2 size:: mebibytes." $1 $OPTS[-s]

	[[ -z "$1" ]] && _failure "No tomb name specified for resizing."
	[[ ! -r "$1" ]] && _failure "Cannot find ::1::" $1

	newtombsize="`option_value -s`"
	[[ -z "$newtombsize" ]] && {
		_failure "Aborting operations: new size was not specified, use -s" }

	is_valid_tomb $tombpath

	_load_key # Try loading new key from option -k and set TOMBKEYFILE

	if option_is_set --tomb-pwd; then
		tomb_pwd="`option_value --tomb-pwd`"
		_verbose "tomb-pwd = ::1 tomb pass::" $tomb_pwd
		ask_key_password "$tomb_pwd"
	else
		ask_key_password
	fi
	[[ $? == 0 ]] || _failure "No valid password supplied."

	local oldtombsize=$(( `stat -c %s "$TOMBPATH" 2>/dev/null` / 1048576 ))

	# New tomb size must be specified
	[[ -n "$newtombsize" ]] || {
		_failure "You must specify the new size of ::1 tomb name::" $TOMBNAME }
	# New tomb size must be an integer
	[[ $newtombsize == <-> ]] || _failure "Size is not an integer."

	# Tombs can only grow in size
	if [[ "$newtombsize" -gt "$oldtombsize" ]]; then

		delta="$(( $newtombsize - $oldtombsize ))"

		_message "Generating ::1 tomb file:: of ::2 size::MiB" $TOMBFILE $newtombsize

		_verbose "Data dump using ::1:: from /dev/urandom" ${DD[1]}
		${=DD} if=/dev/urandom bs=1048576 count=${delta} >> $TOMBPATH
		[[ $? == 0 ]] || {
			_failure "Error creating the extra resize ::1 size::, operation aborted." \
					 $tmp_resize }

		# If same size this allows to re-launch resize if pinentry expires
		# so that it will continue resizing without appending more space.
		# Resizing the partition to the file size cannot harm data anyway.
	elif [[ "$newtombsize" = "$oldtombsize" ]]; then
		_message "Tomb seems resized already, operating filesystem stretch"
	else
		_failure "The new size must be greater then old tomb size."
	fi

	lo_mount "$TOMBPATH"

	_message "opening tomb"
	_cryptsetup luksOpen ${TOMBLOOP} ${TOMBMAPPER} || {
		_failure "Failure mounting the encrypted file." }

	_sudo cryptsetup resize "${TOMBMAPPER}" || {
		_failure "cryptsetup failed to resize ::1 mapper::" $TOMBMAPPER }


	filesystem=`_detect_filesystem /dev/mapper/${TOMBMAPPER}`
	_message "Filesystem detected: ::1 filesystem::" $filesystem
	case $filesystem in
		ext3|ext4)
			_sudo e2fsck -p -f /dev/mapper/${TOMBMAPPER} || {
				_sudo cryptsetup luksClose "${TOMBMAPPER}"
				_failure "e2fsck failed to check ::1 mapper::" $TOMBMAPPER }
			_sudo resize2fs /dev/mapper/${TOMBMAPPER} || {
				_sudo cryptsetup luksClose "${TOMBMAPPER}"
				_failure "resize2fs failed to resize ::1 mapper::" $TOMBMAPPER }
			;;
		btrfs)
			_sudo btrfs check /dev/mapper/${TOMBMAPPER} || {
				_sudo cryptsetup luksClose "${TOMBMAPPER}"
				_failure "filesystem check failed on ::1 mapper::" $TOMBMAPPER }
			# btrfs requires mounting before resize
			local mp=${TOMBNAME}.tomb.resize
			mkdir -p /tmp/${mp}
			_sudo mount /dev/mapper/${TOMBMAPPER} /tmp/${mp}
			_sudo btrfs filesystem resize max /tmp/${mp} || {
				_sudo umount /tmp/${mp}
				_sudo cryptsetup luksClose "${TOMBMAPPER}"
				rmdir /tmp/${mp}
				_failure "filesystem resize failed on ::1 mapper::" $TOMBMAPPER }
			_sudo umount /tmp/${mp}
			rmdir /tmp/${mp}
			;;
		# TODO: report error on unrecognized filesystem
	esac

	# close and free the loop device
	_sudo cryptsetup luksClose "${TOMBMAPPER}"

	return 0
}

# }}}

# {{{ Close

umount_tomb() {
	local tombs how_many_tombs
	local pathmap mapper tombname tombmount loopdev
	local ans pidk pname

	if [ "$1" = "all" ]; then
		mounted_tombs=(`list_tomb_mounts`)
	else
		mounted_tombs=(`list_tomb_mounts $1`)
	fi

	[[ ${#mounted_tombs} == 0 ]] && {
		_failure "There is no open tomb to be closed." }

	[[ ${#mounted_tombs} -gt 1 && -z "$1" ]] && {
		_warning "Too many tombs mounted, please specify one (see tomb list)"
		_warning "or issue the command 'tomb close all' to close them all."
		_failure "Operation aborted." }

	for t in ${mounted_tombs}; do
		mapper=`basename ${t[(ws:;:)1]}`

		# strip square parens from tombname
		tombname=${t[(ws:;:)5]}
		tombmount="${t[(ws:;:)2]}"
		tombfs=${t[(ws:;:)3]}
		tombfsopts=${t[(ws:;:)4]}
		tombloop=${mapper[(ws:.:)4]}

		_verbose "Name: ::1 tomb name::" $tombname
		_verbose "Mount: ::1 mount point::" "$tombmount"
		_verbose "Loop: ::1 mount loop::" $tombloop
		_verbose "Mapper: ::1 mapper::" $mapper

		[[ -e "$mapper" ]] && {
			_warning "Tomb not found: ::1 tomb file::" $1
			_warning "Please specify an existing tomb."
			return 0 }

		option_is_set -n || {
			exec_safe_func_hooks \
				close "$tombmount" "$tombname" "$tombloop" "$mapper"
			exec_hook_res=$?
			[[ $exec_hook_res = 0 ]] || {
				_warning "close exec-hook returns a non-zero error code: ::1 error::" $exec_hook_res
				_failure "Operation aborted"
			}
		}

		_message "Closing tomb ::1 tomb name:: mounted on ::2 mount point::" \
				 $tombname "$tombmount"

		# check if there are binded dirs and close them
		bind_tombs=(`list_tomb_binds $tombname "$tombmount"`)
		for b in ${(f)"$(list_tomb_binds $tombname "$tombmount")"}; do
			bind_mapper="${b[(ws:;:)1]}"
			bind_mount="${b[(ws:;:)2]}"
			_message "Closing tomb bind hook: ::1 hook::" "$bind_mount"
			_sudo umount "$(echo "$bind_mount")" ||
				_failure "Tomb bind hook ::1 hook:: is busy, cannot close tomb." "$bind_mount"
		done

		# check if the tomb is actually still mounted. Background:
		# When mounted on a binded directory in appears twice in 'list_tomb_binds'
		# and will get umounted automatically through the above function
		# causing an error and a remaining (decrypted!) loop device
		# posing a security risk.
		# See https://github.com/dyne/Tomb/issues/273

		# checking for tombs still mounted
		mounted_tombs=(`list_tomb_mounts`)
		for t in ${mounted_tombs}; do
			usedmount=${t[(ws:;:)2]}
			[[ "$usedmount" == "$tombmount" ]] && {
				_verbose "Performing umount of ::1 mount point::" "$tombmount"
				touch "${tombmount}"/.cleanexit
				_sudo umount "${tombmount}"
				[[ $? = 0 ]] || {
					rm -f "${tombmount}"/.cleanexit
					_failure "Tomb is busy, cannot umount!"
				}
			}
		done

		# If we used a default mountpoint and is now empty, delete it
		tombname_regex=${tombname//\[/}
		tombname_regex=${tombname_regex//\]/}

		[[ "$tombmount" =~ "(/run)?/media(/$_USER)?/$tombname_regex" ]] && {
			_sudo rmdir "$tombmount" }

		_sudo cryptsetup luksClose $mapper ||
			_failure "Error occurred in cryptsetup luksClose ::1 mapper::" $mapper

		# Normally the loopback device is detached when unused
		[[ -e "/dev/$tombloop" ]] && {
			_sudo losetup -d "/dev/$tombloop" ||
				_verbose "/dev/$tombloop was already closed."
		}

		_success "Tomb ::1 tomb name:: closed: your bones will rest in peace." $tombname

	done # loop across mounted tombs

	return 0
}

list_processes() {
	# $1 = (optional) name of tomb
	# returns a list of process UIDs, one per line
	local mounted_tombs i
	local pnum puid pcmd powner found
	found=0
	mounted_tombs=(`list_tomb_mounts $1`)
	if [[ "${#mounted_tombs}" -gt 0 ]]; then
		if [[ -z $1 ]]; then
			_success "Listing processes running inside all open tombs..."
		else
			_success "Listing processes running inside tomb '::1 tombname::'..." "$1"
		fi

		for i in ${mounted_tombs}; do
			_verbose "scanning tomb: ::1 tombmount::" $i
			tombmount="${i[(ws:;:)2]}"
			tombname=${i[(ws:;:)5]}
			for pnum in ${(f)"$(_sudo lsof -t +D "$tombmount")"}; do
				found=$(($found + 1))
				_verbose "process found: $pnum"
				puid=$(cat /proc/${pnum}/loginuid)
				pcmd=$(cat /proc/${pnum}/cmdline)
				powner=`_get_username $puid`
				_verbose "process found: $pnum $pcmd ($powner)"
				_message "::1 tombname:: ::2 cmd:: (::3 owner::)" \
						 $tombname $pcmd $powner
			done
		done
	fi
	_message "::1 foundproc:: running processes found inside ::2 numtombs:: open tombs" \
			 $found ${#mounted_tombs}
	return 0
}

# Kill all processes using the tomb
slam_tomb() {
	# $1 = (optional) name of tomb to slam, or "all" if more mounted

	if [ "$1" = "all" ]; then
		mounted_tombs=(`list_tomb_mounts`)
	else
		mounted_tombs=(`list_tomb_mounts $1`)
	fi

	[[ ${#mounted_tombs} == 0 ]] && {
		_failure "There is no open tomb to be closed." }

	[[ ${#mounted_tombs} -gt 1 && -z "$1" ]] && {
		_warning "Too many tombs mounted, please specify one (see tomb list)"
		_warning "or issue the command 'tomb close all' to close them all."
		_failure "Operation aborted." }

	local pnum puid pcmd powner result
	result=0
	# iterate through all mounted tomb affected
	for i in ${mounted_tombs}; do
		tombname=${i[(ws:;:)5]}
		tombmount="${i[(ws:;:)2]}"
		_success "Slamming tomb ::1 tombname:: mounted on ::2 tombmount::" \
				 ${tombname} "${tombmount}"
		# iterate through all processes running in mounted tombs
		for pnum in ${(f)"$(_sudo lsof -t +D "$tombmount")"}; do
			puid=$(cat /proc/${pnum}/loginuid)
			pcmd=$(cat /proc/${pnum}/cmdline)
			powner=`_get_username $puid`
			_verbose "process found: $pnum $pcmd ($powner)"
			# iterate through 3 different signals to send, break on success
			for s in TERM HUP KILL; do
				_message "::1 tombname:: sending ::2 sig:: to ::3 cmd:: (::4 uid::)" \
						 ${tombname} ${s} ${pcmd} ${powner}
				_sudo kill -$s $pnum
				# give some time to the process for a clean quit
				sleep .5
				# stop sending other signals if kill was succesfull
				[[ -r /proc/$pnum ]] || break
			done
			# if process still running then signal failure
			[[ -r /proc/$pnum ]] && {
				_warning "Can't kill ::1 process:: ::2 pcmd:: (::3 powner::)" \
						 $pnum $pcmd $powner
				result=1 }
		done
		# if it failed killing a process, report it
		[[ $result = 0 ]] && umount_tomb $tombname
	done
	return $result
}

# }}} - Tomb close

# {{{ Main routine

main() {

	_ensure_dependencies  # Check dependencies are present or bail out

	local -A subcommands_opts
	### Options configuration
	#
	# Hi, dear developer!  Are you trying to add a new subcommand, or
	# to add some options?	Well, keep in mind that option names are
	# global: they cannot bear a different meaning or behaviour across
	# subcommands.	The only exception is "-o" which means: "options
	# passed to the local subcommand", and thus can bear a different
	# meaning for different subcommands.
	#
	# For example, "-s" means "size" and accepts one argument. If you
	# are tempted to add an alternate option "-s" (e.g., to mean
	# "silent", and that doesn't accept any argument) DON'T DO IT!
	#
	# There are two reasons for that:
	#	 I. Usability; users expect that "-s" is "size"
	#	II. Option parsing WILL EXPLODE if you do this kind of bad
	#		things (it will complain: "option defined more than once")
	#
	# If you want to use the same option in multiple commands then you
	# can only use the non-abbreviated long-option version like:
	# -force and NOT -f
	#
	main_opts=(q -quiet=q D -debug=D h -help=h v -version=v f -force=f -tmp: U: G: T: -no-color -unsafe g -gpgkey=g -sudo:)
	subcommands_opts[__default]=""
	# -o in open and mount is used to pass alternate mount options
	subcommands_opts[open]="n -nohook=n k: -kdf: -kdftype: -kdfmem: o: -ignore-swap -tomb-pwd: r: R: -sphx-host: -sphx-user: p -preserve-ownership=p"
	subcommands_opts[mount]=${subcommands_opts[open]}

	subcommands_opts[create]="" # deprecated, will issue warning

	# -o in forge and lock is used to pass an alternate cipher.
	subcommands_opts[forge]="-ignore-swap k: -kdf: -kdftype: -kdfmem: o: -tomb-pwd: -use-random r: R: -sphx-host: -sphx-user: "
	subcommands_opts[dig]="-ignore-swap s: -size=s "
	subcommands_opts[lock]="-ignore-swap k: -kdf: -kdftype: -kdfmem: o: -tomb-pwd: r: R: -sphx-host: -sphx-user: -filesystem: "
	subcommands_opts[setkey]="k: -ignore-swap -kdf: -kdftype: -kdfmem: -tomb-old-pwd: -tomb-pwd: r: R: -sphx-host: -sphx-user: "
	subcommands_opts[engrave]="k: "

	subcommands_opts[passwd]="k: -ignore-swap -kdf: -kdftype: -kdfmem: -tomb-old-pwd: -tomb-pwd: r: R: -sphx-host: -sphx-user: "
	subcommands_opts[close]=""
	subcommands_opts[help]=""
	subcommands_opts[slam]=""
	subcommands_opts[ps]=""
	subcommands_opts[list]="-get-mountpoint "

	subcommands_opts[index]=""
	subcommands_opts[search]=""

	subcommands_opts[bury]="k: -tomb-pwd: r: R: -sphx-host: -sphx-user: "
	subcommands_opts[exhume]="k: -tomb-pwd: r: R: -sphx-host: -sphx-user: "
	subcommands_opts[cloak]="k: "
	subcommands_opts[uncloak]="k: "
	# subcommands_opts[decompose]=""
	# subcommands_opts[recompose]=""
	# subcommands_opts[install]=""
	subcommands_opts[askpass]=""
	subcommands_opts[source]=""
	subcommands_opts[resize]="-ignore-swap s: -size=s k: -tomb-pwd: r: R: -sphx-host: -sphx-user: "
	subcommands_opts[check]="-ignore-swap "
	#	 subcommands_opts[translate]=""

	### Detect subcommand
	local -aU every_opts #every_opts behave like a set; that is, an array with unique elements
	for optspec in $subcommands_opts$main_opts; do
		for opt in ${=optspec}; do
			every_opts+=${opt}
		done
	done
	local -a oldstar
	oldstar=("${(@)argv}")
	#### detect early: useful for --option-parsing
	zparseopts -M -D -Adiscardme ${every_opts}
	if [[ -n ${(k)discardme[--option-parsing]} ]]; then
		print $1
		if [[ -n "$1" ]]; then
			return 1
		fi
		return 0
	fi
	unset discardme
	if ! zparseopts -M -E -D -Adiscardme ${every_opts}; then
		_failure "Error parsing."
		return 127
	fi
	unset discardme
	subcommand=$1
	if [[ -z $subcommand ]]; then
		subcommand="__default"
	fi

	if [[ -z ${(k)subcommands_opts[$subcommand]} ]]; then
		_warning "There's no such command \"::1 subcommand::\"." $subcommand
		exitv=127 _failure "Please try -h for help."
	fi
	argv=("${(@)oldstar}")
	unset oldstar

	### Parsing global + command-specific options
	# zsh magic: ${=string} will split to multiple arguments when spaces occur
	set -A cmd_opts ${main_opts} ${=subcommands_opts[$subcommand]}
	# if there is no option, we don't need parsing
	if [[ -n $cmd_opts ]]; then
		zparseopts -M -E -D -AOPTS ${cmd_opts}
		if [[ $? != 0 ]]; then
			_warning "Some error occurred during option processing."
			exitv=127 _failure "See \"tomb help\" for more info."
		fi
	fi
	#build PARAM (array of arguments) and check if there are unrecognized options
	ok=0
	PARAM=()
	for arg in $*; do
		if [[ $arg == '--' || $arg == '-' ]]; then
			ok=1
			continue #it shouldn't be appended to PARAM
		elif [[ $arg[1] == '-' ]]; then
			if [[ $ok == 0 ]]; then
				exitv=127 _failure "Unrecognized option ::1 arg:: for subcommand ::2 subcommand::" $arg $subcommand
			fi
		fi
		PARAM+=$arg
	done
	# First parameter actually is the subcommand: delete it and shift
	[[ $subcommand != '__default' ]] && { PARAM[1]=(); shift }

	### End parsing command-specific options

	# Use colors unless told not to
	{ ! option_is_set --no-color } && { autoload -Uz colors && colors }
	# Some options are only available during insecure mode
	{ ! option_is_set --unsafe } && {
		for opt in --tomb-pwd --tomb-old-pwd; do
			{ option_is_set $opt } && {
				exitv=127 _failure "You specified option ::1 option::, which is DANGEROUS and should only be used for testing\nIf you really want so, add --unsafe" $opt }
		done
	}
	# read -t or --tmp flags to set a custom temporary directory
	option_is_set --tmp && TMPDIR=$(option_value --tmp)

	option_is_set --sudo && {
	    local _opt=`basename $(option_value --sudo)`
            _message "Privilege escalation tool configured: ::1 exec::" $_opt
	}

	# When we run as root, we remember the original uid:gid to set
	# permissions for the calling user and drop privileges
	_whoami # Reset _UID, _GID, _TTY

	[[ -z $PARAM ]] && {
		_verbose "Tomb command: ::1 subcommand::" $subcommand
	} || {
		_verbose "Tomb command: ::1 subcommand:: ::2 param::" $subcommand $PARAM
	}

	[[ -z $_UID ]] || {
		_verbose "Caller: uid[::1 uid::], gid[::2 gid::], tty[::3 tty::]." \
				 $_UID $_GID $_TTY
	}

	_verbose "Temporary directory: $TMPDIR"

	# Process subcommand
	case "$subcommand" in

		# USAGE
		help)
			usage
			;;

		# DEPRECATION notice (leave here as 'create' is still present in old docs)
		create)
			_warning "The create command is deprecated, please use dig, forge and lock instead."
			_warning "For more informations see Tomb's manual page (man tomb)."
			_failure "Operation aborted."
			;;

		# CREATE Step 1: dig -s NN file.tomb
		dig)
			dig_tomb $PARAM
			;;

		# CREATE Step 2: forge file.tomb.key
		forge)
			forge_key $PARAM
			;;

		# CREATE Step 3: lock -k file.tomb.key file.tomb
		lock)
			lock_tomb_with_key $PARAM
			;;

		# Open the tomb
		mount|open)
			mount_tomb $PARAM
			;;

		# List all processes using a tomb
		ps)
			list_processes $PARAM
			;;

		# Slam a tomb killing all processes running inside
		slam)
			slam_tomb $PARAM
			;;

		# Close the tomb
		# `slam` is used to force closing.
		umount|close)
			[[ "$subcommand" == "slam" ]] && {
				SLAM=1
				[[ $LSOF == 0 ]] && {
					unset SLAM
					_warning "lsof not installed: cannot slam tombs."
					_warning "Trying a regular close." }}
			umount_tomb $PARAM[1]
			;;

		# Grow tomb's size
		resize)
			[[ $RESIZER == 0 ]] && {
				_failure "Resize2fs not installed: cannot resize tombs." }
			resize_tomb $PARAM[1]
			;;

		## Contents manipulation

		# Index tomb contents
		index)
			index_tombs $PARAM[1]
			;;

		# List tombs
		list)
			list_tombs $PARAM[1]
			;;

		# Search tomb contents
		search)
			search_tombs $PARAM
			;;

		## Locking operations

		# Export key to QR Code
		engrave)
			[[ $QRENCODE == 0 ]] && {
				_failure "QREncode not installed: cannot engrave keys on paper." }
			engrave_key $PARAM
			;;

		# Change password on existing key
		passwd)
			change_passwd $PARAM[1]
			;;

		# Change tomb key
		setkey)
			change_tomb_key $PARAM
			;;

		# STEGANOGRAPHY: hide key inside an image
		bury)
			[[ $STEGHIDE == 0 ]] && {
				_failure "Steghide not installed: cannot bury keys into images." }
			bury_key $PARAM[1]
			;;

		# STEGANOGRAPHY: read key hidden in an image
		exhume)
			[[ $STEGHIDE == 0 ]] && {
				_failure "Steghide not installed: cannot exhume keys from images." }
			exhume_key $PARAM[1]
			;;

		# STEGANOGRAPHY: transform key into text using cipher
		cloak)
			[[ $CLOAKIFY == 0 ]] && {
				_failure "Cloakify not installed: cannot cipher keys into texts" }
			cloakify_key $PARAM
			;;

		# STEGANOGRAPHY: read key from text using cipher
		uncloak)
			[[ $DECLOAKIFY == 0 ]] && {
				_failure "Decloakify not installed: cannot decipher keys from texts" }
			decloakify_key $PARAM
			;;


		## Internal commands useful to developers

		# Make tomb functions available to the calling shell or script
		'source')	return 0 ;;

		# Ask user for a password interactively
		askpass)	ask_password $PARAM[1] $PARAM[2] ;;

		# Default operation: presentation, or version information with -v
		__default)
			_print "Tomb ::1 version:: - a strong and gentle undertaker for your secrets" $VERSION
			echo
			_print " Copyright (C) 2007-2021 Dyne.org Foundation, License GNU GPL v3+"
			_print " This is free software: you are free to change and redistribute it"
			_print " For the latest sourcecode go to <http://dyne.org/software/tomb>"
			echo
			option_is_set -v && {
				local langwas=$LANG
				LANG=en
				_print " This source code is distributed in the hope that it will be useful,"
				_print " but WITHOUT ANY WARRANTY; without even the implied warranty of"
				_print " MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE."
				LANG=$langwas
				_print " When in need please refer to <http://dyne.org/support>."
				echo
				_print "System utils:"
				echo
				cat <<EOF
  `zsh --version`
  `sudo -V | head -n1`
  `cryptsetup --version`
  `pinentry --version | head -n1`
  `findmnt -V`
  `gpg --version | head -n1` - key forging algorithms (GnuPG symmetric ciphers):
  `list_gnupg_ciphers`
EOF
				echo
				_print "Optional utils:"
				echo
				_list_optional_tools version
				return 0
			}
			usage
			;;

		# Reject unknown command and suggest help
		*)
			_warning "Command \"::1 subcommand::\" not recognized." $subcommand
			_message "Try -h for help."
			return 1
			;;
	esac
	return $?
}

# }}}

# {{{ Run

main "$@" || exit $?   # Prevent `source tomb source` from exiting

# }}}