Tomb/src/tomb

#!/bin/zsh
#
# Tomb, the Crypto Undertaker
#
# a tool to easily operate file encryption of private and secret data
#
# Copyleft (C) 2007-2011 Denis Roio <jaromil@dyne.org>
#
# 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, write to:
# Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

VERSION=1.1
DATE=May/2011
TOMBEXEC=$0
TOMBOPENEXEC="tomb-open"
typeset -a OLDARGS
for arg in ${argv}; do OLDARGS+=($arg); done
STEGHIDE=1
MOUNTOPTS="rw,noatime,nodev"

#declare global variables
QUIET=0
DEBUG=0
typeset -A global_opts
typeset -A opts

# PATH=/usr/bin:/usr/sbin:/bin:/sbin

autoload colors; colors

# standard output message routines
# it's always useful to wrap them, in case we change behaviour later
notice() { if [[ $QUIET == 0 ]]; then print "$fg_bold[green][*]$fg_no_bold[white] $1" >&2; fi }
error()  { if [[ $QUIET == 0 ]]; then print "$fg[red][!]$fg[white] $1" >&2; fi }
func()   { if [[ $DEBUG == 1 ]]; then   print "$fg[blue][D]$fg[white] $1" >&2; fi }
act()    {
    if [[ $QUIET == 0 ]]; then
	if [ "$1" = "-n" ]; then
	    print -n "$fg_bold[white] . $fg_no_bold[white] $2" >&2;
	else
	    print "$fg_bold[white] . $fg_no_bold[white] $1" >&2;
	fi
    fi
}

check_bin() {
    # which dd command to use
    which dcfldd > /dev/null
    if [ $? = 0 ]; then
	DD="dcfldd"
    else
	DD=dd
    fi

    # which wipe command to use
    which wipe > /dev/null
    if [ $? = 0 ]; then
	WIPE=(wipe -f -s)
    else
	WIPE=(rm -f)
    fi

    # check for filesystem creation progs
    which mkfs.ext4 > /dev/null
    if [ $? = 0 ]; then
	MKFS=(mkfs.ext4 -q -F -j -L)
    else
	MKFS=(mkfs.ext3 -q -F -j -L)
    fi

    # check for sudo
    which sudo > /dev/null
    if [ $? != 0 ]; then
	error "Cannot find sudo. Please install it"
	exit 1
    fi

    # check for steghide
    which steghide > /dev/null
    if [ $? != 0 ]; then
	STEGHIDE=0
    fi

    which cryptsetup > /dev/null
    if [ $? != 0 ]; then
        error "Cannot find cryptsetup. Please install it."
        exit 1
    fi

    which pinentry > /dev/null
    if [ $? != 0 ]; then
        error "Cannot find pinentry. Please install it."
        exit 1
    fi
 
    # check for tomb-open script
    if [ "$0" = "./tomb" ]; then
	TOMBOPENEXEC="./tomb-open"
    elif [ "$0" != "tomb" ]; then
	TOMBOPENEXEC="`dirname $0`/tomb-open"
    fi
}

# safe dir creation function
safe_dir() {
    which mktemp &> /dev/null
    if [[ $? = 0 ]]; then
        mktemp -d /dev/shm/$1.$$.XXXXXXX
        return
    fi
    dir="/dev/shm/$1.$$.$RANDOM.$RANDOM"
    (umask 077 && mkdir "$dir") || print "-1"
    print "$dir"
}

#check if there is swap activated
check_swap() {
    # Return 0 if NO swap is used, 1 if swap is used
    # TODO: it should return 2 if swap is used, but encrypted
    nlines=$(wc -l /proc/swaps|cut -f1 -d ' ')
    if [[ $nlines -gt 1 ]]; then
        r=1
    else
        #and return 2
        r=0
    fi
    if [[ $1 == out ]]; then
        echo $r;
    fi
    return $r;
}

# we use pinentry now
# comes from gpg project and is much more secure
# it also conveniently uses the right toolkit
ask_password() {

    # pinentry has no custom icon setting
    # so we need to temporary modify the gtk theme
    if [ -r /usr/local/share/themes/tomb/gtk-2.0-key/gtkrc ]; then
	GTK2_RC=/usr/local/share/themes/tomb/gtk-2.0-key/gtkrc
    elif [ -r /usr/share/themes/tomb/gtk-2.0-key/gtkrc ]; then
	GTK2_RC=/usr/share/themes/tomb/gtk-2.0-key/gtkrc
    fi

    cat <<EOF | GTK2_RC_FILES=${GTK2_RC} pinentry 2>/dev/null | awk '/^D / { sub(/^D /, ""); print }'
OPTION ttyname=$TTY
OPTION lc-ctype=$LANG
SETTITLE Insert tomb password
SETDESC Open tomb: $1
SETPROMPT Password:
GETPIN
EOF

}

# drop privileges
exec_as_user() {
    if ! [ $SUDO_USER ]; then
	exec $@[@]
	return $?
    fi

    func "exec_as_user '$SUDO_USER': ${(f)@}"
    sudo -u $SUDO_USER "${@[@]}"
    return $?
}


# escalate privileges
check_priv() {
    if [ $UID != 0 ]; then
	func "Using sudo for root execution of 'tomb ${(f)OLDARGS}'"
	# check if sudo has a timestamp active
	sudok=false
	sudo -n ${TOMBEXEC} &> /dev/null
	if [ $? != 0 ]; then # if not then ask a password
	    cat <<EOF | pinentry 2>/dev/null | awk '/^D / { sub(/^D /, ""); print }' | sudo -S -v
OPTION ttyname=$TTY
OPTION lc-ctype=$LANG
SETTITLE Super user privileges required
SETDESC Sudo execution of Tomb ${OLDARGS[@]}
SETPROMPT Insert your USER password:
GETPIN
EOF
	fi
	sudo "${TOMBEXEC}" "${(@)OLDARGS}"
	exit $?
    fi # are we root already
    return 0
}

get_arg_tomb() {
# set up variables to be used by caller:
# tombfile - filename without path
# tombdir  - directory where the tomb is
# tombname - name of the tomb (filename without extension)
# the full path is made with $tombdir/$tombfile
    if [ -z $1 ]; then
	error "internal: get_arg_tomb called without argument"
	return 1
    fi

    arg=${1}
    if ! [ -r ${arg} ]; then
	error "file not found: $arg"
	return 1
    fi

    tombfile=`basename $arg`
    tombdir=`dirname $arg`

    file ${tombdir}/${tombfile} | grep -i 'luks encrypted file' 2>&1 >/dev/null
    if [ $? != 0 ]; then
	error "$arg is not a valid tomb file, operation aborted"
	return 1
    fi

    tombname=${tombfile%%\.*}
    func "tomb found: ${tombdir}/${tombfile}"
    # now check if the key is kept beside or in args
    # we use the extension .key

    # the problem with .tomb.gpg is that decoding by hand using gpg it
    # can override the tomb contents if the key is in the same
    # directory than the tomb
    if [ $KEY ]; then
	tombkey=$KEY # commandline -k flag
	act "tomb key specified manually: $tombkey"
    elif [ -r ${tombdir}/${tombname}.tomb.key ]; then
	tombkey=${tombdir}/${tombname}.tomb.key
	act "key found for tomb '${tombname}': ${tombkey}"
    else
	error "key not found for tomb '${tombname}'"
	return 1
    fi
    return 0
}

usage() {
	cat <<EOF
Tomb $VERSION - a strong and gentle undertaker for your secrets

 Copyright (C) 2007-2011 Dyne.org Foundation, License GNU GPL v3+
 This is free software: you are free to change and redistribute it
 The latest Tomb sourcecode is published on <http://tomb.dyne.org>

Syntax: tomb [options] command [file] [place]

Commands:

 create     create a new tomb FILE and its keys
 open       open an existing tomb FILE on PLACE
 list       list all open tombs or the one called FILE
 close      close the open tomb called FILE (or all)
 slam       close tomb FILE and kill all pids using it
EOF
if [ "$STEGHIDE" = 1 ]; then
    cat <<EOF
 bury       hide a tomb key FILE inside a jpeg PLACE
 exhume     extract a tomb key FILE from a jpeg PL
EOF
fi
cat <<EOF

Options:

 -s     size of the tomb file when creating one (in MB)
 -k     path to the key to use for opening a tomb
 -n     don't process the hooks found in tomb
 -o     mount options used to open (default: rw,noatime,nodev)

 -h     print this help
 -v     version information for this tool
 -q     run quietly without printing informations
 -D     print debugging information at runtime

For more informations on Tomb read the manual: man tomb
Please report bugs on <http://bugs.dyne.org>.
EOF
}

generate_translatable_strings() {
    cat <<EOF
# Tomb - The Crypto Undertaker.
# Copyright (C) 2007-2011 Dyne.org Foundation
# Denis Roio <jaromil@dyne.org>, 2011.
#
#, fuzzy
msgid ""
msgstr ""
"Project-Id-Version: Tomb $VERSION\n"
"PO-Revision-Date: `date`\n"
"Last-Translator: Denis Roio <jaromil@dyne.org>\n"
"Language-Team: Tomb developers <crypto@lists.dyne.org>\n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=CHARSET\n"
"Content-Transfer-Encoding: 8bit\n"

#
#: commandline help
#

msgid ""
EOF

    usage | awk '
{ print "\"" $0 "\"" }'
cat <<EOF
msgstr ""

#
# tomb internal messages
#

EOF

    cat $TOMBEXEC | awk '
/notice ".*"$/ { sub( /notice/ , "");
                 print "#: notice"; print "msgid " $0; print "msgstr \"\"\n" }

/act ".*"$/ { sub( /act/ , "");
              print "#: act"; print "msgid " $0; print "msgstr \"\"\n" }
'
}

create_tomb() {
    if ! option_is_set --ignore-swap && [[ `check_swap out` == 1 ]]; then
        error "You have swap activated; use --ignore-swap if you want to skip this check"
        act "Using encryption with swap activated is very bad, because some files, or even your secret key, could be written on hard disk."
        act "However, it could be that your swap is encrypted. If this is case, this is ok. Then, use --ignore-swap to skip this check"
        exit 1
    fi
    if ! [ ${CMD2} ]; then
        error "no tomb name specified for creation"
        return 1
    fi

    tombfile=`basename ${CMD2}`
    tombdir=`dirname ${CMD2}`
    # make sure the file has a .tomb extension
    tombname=${tombfile%%\.*}
    tombfile=${tombname}.tomb
	 tombsize=$opts[-s]
    
    if [[ $tombsize != <-> ]]; then
        error "Size is not an integer"
        return 1
    fi
    
    if [ -e ${tombdir}/${tombfile} ]; then
	    error "tomb exists already. I'm not digging here:"
	    ls -lh ${tombdir}/${tombfile}
	    return 1
    fi
    
    if option_is_set -k; then
        tombkey="`option_value -k`.tomb.key"
    else
        tombkey="${tombdir}/${tombfile}.key"
    fi

    if [ -e "${tombkey}" ]; then
        error "tomb key already exists. Quitting."
        ls -lh ${tombkey}
        return 1
    fi

    notice "Creating a new tomb in ${tombdir}/${tombfile}"

    if [ -z $tombsize ]; then
        act "No size specified, summoning the Tomb Undertaker to guide us in the creation."
        "$TOMBOPENEXEC" &
        wait $!
        return 0
    fi

    tombsize_4k=`expr $tombsize \* 1024 / 4`
    act "Generating ${tombfile} of ${tombsize}Mb (${tombsize_4k} blocks of 4Kb)"
    $DD if=/dev/urandom bs=4k count=${tombsize_4k} of=${tombdir}/${tombfile}

    if [ $? = 0 -a -e ${tombdir}/${tombfile} ]; then
	act "OK: `ls -lh ${tombdir}/${tombfile}`"
    else
	error "Error creating the tomb ${tombdir}/${tombfile}, operation aborted."
	exit 1
    fi

    nstloop=`losetup -f` # get the number for next loopback device
    losetup -f ${tombdir}/${tombfile} # allocates the next loopback for our file

    # create the keyfile in tmpfs so that we leave less traces in RAM
    keytmp=`safe_dir tomb`
    if [ "$keytmp" = "-1" ]; then
	error "error creating temp dir"
	exit 1
    fi
    #rm -f $keytmp
    # ?????? creo, cancello e ricreo ??????
    #mkdir -p $keytmp
    mount tmpfs "${keytmp}" -t tmpfs -o size=1m
    if [ $? != 0 ]; then
	error "cannot mount tmpfs filesystem in volatile memory"
	error "operation aborted."
	losetup -d $nstloop
	rm -r "${keytmp}"
	exit 1
    fi
    act "Generating secret key..."
    act "this operation takes time, keep using this computer on other tasks,"
    act "once done you will be asked to choose a password for your tomb."
    act "To make it faster you can move the mouse around"
    touch ${keytmp}/tomb.tmp
    chmod 0600 ${keytmp}/tomb.tmp
    if [[ $DD = "dcfldd" ]]; then
        $DD bs=1 count=256 if=/dev/random of=${keytmp}/tomb.tmp statusinterval=1
    else
        $DD bs=1 count=256 if=/dev/random of=${keytmp}/tomb.tmp
    fi
    if ! [ -r ${keytmp}/tomb.tmp ]; then
	error "cannot generate encryption key, operation aborted."
	umount ${keytmp}
	losetup -d $nstloop
	rm -r $keytmp
	exit 1
    fi

    notice "Setup your secret key file ${tombkey}"

    # here user is prompted for key password
    for c in 1 2 3; do
	# 3 tries to write two times a matching password
	tombpass=`exec_as_user ${TOMBEXEC} askpass ${tombname}`
	tombpasstmp=$tombpass
	tombpass=`exec_as_user ${TOMBEXEC} askpass "${tombname} (again)"`
	if [ "$tombpasstmp" = "$tombpass" ]; then
	    break;
	fi
	unset tombpasstmp
	unset tombpass
    done

    if [ -z $tombpass ]; then
	error "passwords don't match, aborting operation"
	umount ${keytmp}
	losetup -d $nstloop
	rm -r $keytmp
	exit 1
    fi


    gpg \
	--openpgp --batch --no-options --no-tty --passphrase-fd 0 2>/dev/null \
	-o "${tombkey}" -c -a ${keytmp}/tomb.tmp <<< ${tombpass}

    # if [ $? != 0 ]; then
    # 	error "setting password failed: gnupg returns 2"
    # 	umount ${keytmp}
    # 	losetup -d $nstloop
    # 	rm -r $keytmp
    # 	exit 1
    # fi

    act "formatting Luks mapped device"
	# we use aes-cbc-essiv with sha256
	# for security, performance and compatibility
    cryptsetup --batch-mode \
	--cipher aes-cbc-essiv:sha256 --key-size 256 \
	luksFormat ${nstloop} ${keytmp}/tomb.tmp

    if ! [ $? = 0 ]; then
	act "operation aborted."
	exit 0
    fi

    cryptsetup --key-file ${keytmp}/tomb.tmp --cipher aes luksOpen ${nstloop} tomb.tmp
    ${WIPE[@]} ${keytmp}/tomb.tmp
    umount ${keytmp}
    rm -r ${keytmp}

 #  cryptsetup luksDump ${nstloop}

    act "formatting your Tomb with Ext3/Ext4 filesystem"
    ${MKFS} ${tombname} /dev/mapper/tomb.tmp

    if [ $? != 0 ]; then
	error "Tomb format returns error"
	error "your tomb ${tombfile} maybe corrupt"
    fi

    sync

    cryptsetup luksClose tomb.tmp
    losetup -d ${nstloop}

    # set permissions on the tomb
    ME=${SUDO_USER:-$(whoami)}
    chmod 0600 "${tombdir}/${tombfile}"
    chown $(id -u $ME):$(id -g $ME) "${tombdir}/${tombfile}"

    act "done creating $tombname encrypted storage (using Luks dm-crypt AES/SHA256)"
    notice "Your tomb is ready in ${tombdir}/${tombfile} and secured with key ${tombkey}"

}

mount_tomb() {
    notice "Commanded to open tomb $CMD2"
    if ! option_is_set --ignore-swap && [[ `check_swap out` == 1 ]]; then
        error "You have swap activated; use --ignore-swap if you want to skip this check"
        act "Using encryption with swap activated is very bad, because some files, or even your secret key, could be written on hard disk."
        act "However, it could be that your swap is encrypted. If this is case, this is ok. Then, use --ignore-swap to skip this check"
        exit 1
    fi
    if ! [ ${CMD2} ]; then
        error "no tomb name specified for creation"
        return 1
    fi

    # TODO: eliminate this function
    get_arg_tomb $CMD2

    local tombkey
    if option_is_set -k ; then
	if [[ "`option_value -k`" == "-" ]]; then
	    # take key from stdin
	    local tombkeydir
	    tombkeydir=`safe_dir`
	    cat > ${tombkeydir}/stdin.tmp
	    tombkey=${tombkeydir}/stdin.tmp
	else
	    # take key from a file
            tombkey=`option_value -k`
	fi
    else
	# guess key as lying besides the tomb
        tombkey="${PARAM[1]}.key"
    fi
    echo the key used is $tombkey
    if [ $? != 0 ]; then
        error "operation aborted."
        return 1
    fi

    if ! [ $CMD3 ]; then
        tombmount=/media/${tombfile}
        act "mountpoint not specified, using default: $tombmount"
    elif ! [ -x $CMD3 ]; then
        error "mountpoint $CMD3 doesn't exist, operation aborted."
        if [ -n "$usbkey_mount" ]; then
            umount $usbkey_mount
            rmdir  $usbkey_mount
            unset usbkey_mount
        fi
        return 1
    else
        tombmount=$CMD3
    fi

    # check if its already open
    mount -l | grep "${tombname}.tomb.*\[$tombname\]$" 2>&1 > /dev/null
    if [ $? = 0 ]; then
        error "$tombname is already mounted on $tombmount"
        act "tomb list - show all tombs currently open"
        if [ -n "$usbkey_mount" ]; then
            umount $usbkey_mount
            rmdir  $usbkey_mount
            unset usbkey_mount
        fi
        error "operation aborted."
        return 1
    fi

    notice "mounting $tombfile on mountpoint $tombmount"


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

    nstloop=`losetup -f`
    if [ $? = 255 ]; then
        error "too many tomb opened. Please close any of them to open another tomb"
        exit 1
    fi
    losetup -f ${tombdir}/${tombfile}

    act "check for a valid LUKS encrypted device"
    cryptsetup isLuks ${nstloop}
    if [ $? != 0 ]; then
        # is it a LUKS encrypted nest? see cryptsetup(1)
        error "$tombfile is not a valid Luks encrypted storage file"
        $norm || rmdir $tombmount 2>/dev/null
        return 1
    fi

    # save date of mount in minutes since 1970
    mapdate=`date +%s`

    mapper="tomb.${tombname}.${mapdate}.`basename $nstloop`"
    keyname=`basename $tombkey | cut -d. -f1`

    notice "Password is required for key ${keyname}"
    for c in 1 2 3; do
	if [ $c = 1 ]; then
	    tombpass=`exec_as_user ${TOMBEXEC} askpass ${keyname}`
	else
	    tombpass=`exec_as_user ${TOMBEXEC} askpass "$keyname (retry $c)"`
	fi
    (gpg --batch --passphrase-fd 0 --no-tty --no-options \
        -d "${tombkey}" 2> /dev/null <<< ${tombpass} ) \
    | cryptsetup --key-file - luksOpen ${nstloop} ${mapper}
	unset tombpass

	# if key was from stdin delete temp file and dir
	if [ $tombkeydir ]; then
	    ${WIPE[@]} ${tombkey}
	    rmdir $tombkeydir
	fi

	if [ -r /dev/mapper/${mapper} ]; then
	    break;  # password was correct
	fi
    done

    if ! [ -r /dev/mapper/${mapper} ]; then
        error "failure mounting the encrypted file"
        losetup -d ${nstloop}
        $norm || rmdir ${tombmount} 2>/dev/null
        return 1
    fi

    act "encrypted storage filesystem check"
    fsck -p -C0 /dev/mapper/${mapper}
    act "tomb engraved as $tombname"
    tune2fs -L ${tombname} /dev/mapper/${mapper} > /dev/null

    mount -o $MOUNTOPTS /dev/mapper/${mapper} ${tombmount}

    # Ensure the user can write the disk - 10x Hellekin :)
    ME=${SUDO_USER:-$(whoami)}
    chmod 0750 ${tombmount}
    chown $(id -u $ME):$(id -g $ME) ${tombmount}

    notice "encrypted storage $tombfile succesfully mounted on $tombmount"
    if ! [ $NOBIND ]; then
        exec_safe_bind_hooks ${tombmount}
        exec_safe_post_hooks ${tombmount} open
    fi
    return 0
}

encode_key() {
    tombkey=$CMD2
    imagefile=$CMD3

    file $tombkey | grep PGP > /dev/null
    if [ $? != 0 ]; then
	error "encode failed: $tombkey is not a tomb key"
	return 1
    fi
    file $imagefile | grep JPEG > /dev/null
    if [ $? != 0 ]; then
	error "encode failed: $imagefile is not a jpeg image"
	return 1
    fi

    notice "Encoding key $tombkey inside image $imagefile"
    act "please choose a password for the encoding"

    # here user is prompted for key password
    for c in 1 2 3; do
	# 3 tries to write two times a matching password
	tombpass=`exec_as_user ${TOMBEXEC} askpass ${tombkey}`
	tombpasstmp=$tombpass
	tombpass=`exec_as_user ${TOMBEXEC} askpass "${tombkey} (again)"`
	if [ "$tombpasstmp" = "$tombpass" ]; then
	    break;
	fi
	unset tombpasstmp
	unset tombpass
    done

    if [ -z $tombpass ]; then
	error "passwords don't match, aborting operation."
	return 1
    fi

    awk '
/^-----/ {next}
/^Version/ {next}
{print $0}' ${tombkey} \
    | steghide embed --embedfile - --coverfile ${imagefile} \
      -p ${tombpass} -z 9 -e serpent cbc
    if [ $? != 0 ]; then
	error "encoding error: steghide reports problems"
	res=1
    else
	notice "tomb key encoded succesfully into image ${imagefile}"
	res=0
    fi

    unset tombpass

    return $res
}

decode_key() {
    tombname=$CMD2
    imagefile=$CMD3
    res=1

    file $imagefile | grep JPEG > /dev/null
    if [ $? != 0 ]; then
	error "encode failed: $imagefile is not a jpeg image"
	return 1
    fi

    keyfile=${tombname%%\.*}.tomb.key
    notice "Trying to exhume a key out of image $imagefile"
    for c in 1 2 3; do
	if [ $c = 1 ]; then
	    tombpass=`exec_as_user ${TOMBEXEC} askpass ${keyfile}`
	else
	    tombpass=`exec_as_user ${TOMBEXEC} askpass "$keyfile (retry $c)"`
	fi
	steghide extract -sf ${imagefile} -p ${tombpass} -xf - \
	    | awk '
BEGIN {
print "-----BEGIN PGP MESSAGE-----"
}
{ print $0 }
END {
print "-----END PGP MESSAGE-----"
}' > ${keyfile}

	if [ "`cat ${keyfile} | wc -l`" != "3" ]; then
	    act "${keyfile} succesfully decoded"
	    res=0
	    break;
	fi
    done

    unset tombpass

    if [ $res != 0 ]; then
	error "nothing found."
    fi

    return $res
}

exec_safe_bind_hooks() {
    if [[ -n ${(k)opts[-o]} ]]; then
        MOUNTOPTS=${opts[-o]}
    fi
  local MOUNTPOINT="${1}"
  local ME=${SUDO_USER:-$(whoami)}
  local HOME=$(grep $ME /etc/passwd | sed "s/^${ME}:.*:.*:.*:.*:\([\/a-z]*\):.*$/\1/" 2>/dev/null)
  if [ $? -ne 0 ]; then
      error "how pitiful!  A tomb, and no HOME"
      return 1
  fi
  if [ -z "$MOUNTPOINT" -o ! -d "$MOUNTPOINT" ]; then
      error "cannot exec bind hooks without a mounted tomb."
      return 1
   fi
   if ! [ -r "$MOUNTPOINT/bind-hooks" ]; then
      func "bind-hooks not found in $MOUNTPOINT"
      return 1
   fi
   typeset -al mounted
   typeset -Al maps
   maps=($(<"$MOUNTPOINT/bind-hooks"))
   for dir in ${(k)maps}; do
      if [ "${dir[1]}" = "/" -o "${dir[1,2]}" = ".." ]; then
	  error "bind-hooks map format: local/to/tomb local/to/\$HOME"
	  continue
      fi
      if [ "${${maps[$dir]}[1]}" = "/" -o "${${maps[$dir]}[1,2]}" = ".." ]; then
	  error "bind-hooks map format: local/to/tomb local/to/\$HOME.  Rolling back"
	  for dir in ${mounted}; do umount $dir; done
	  return 1
      fi
      if [ ! -r "$HOME/${maps[$dir]}" ]; then
	  error "bind-hook target not existent, skipping $HOME/${maps[$dir]}"
      elif [ ! -r "$MOUNTPOINT/$dir" ]; then
	  error "bind-hook source not found in tomb, skipping ${MOUNTPOINT}/${dir}"
      else
	  mount -o bind,$MOUNTOPTS $MOUNTPOINT/$dir $HOME/${maps[$dir]}
	  mounted+=("$HOME/${maps[$dir]}")
      fi
   done
}

exec_safe_post_hooks() {
    local mnt=$1 # first argument is where the tomb is mounted
    local ME=${SUDO_USER:-$(whoami)}
    if ! [ -x ${mnt}/post-hooks ]; then return; fi
    # if 'post-hooks' is found inside the tomb, check it: if it is an
    # executable, launch 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.  this feature opens the possibility to
    # make encrypted executables.
    cat ${mnt}/post-hooks | head -n1 | grep '^#!/'
    if [ $? = 0 ]; then
	act "post hooks found, executing as user $SUDO_USER"
	exec_as_user ${mnt}/post-hooks $2
    fi
}

kill_tomb() {
    # $1 = pids to kill
    # $2 = type of kill
    local e p
    # substitute the \n with space
    e=${1//$'\n'/ }
    # split the string at space delim
    # so we can get a for loop honestly
    e=(${(s: :)e})
    for p in $e; do
        func "killing PID $p..."
        if [[ "$2" == "soft" ]]; then
            kill -USR1 $p
        elif [[ "$2" == "hard" ]]; then
            kill -TERM $p
        elif [[ "$2" == "must die" ]]; then
            kill -KILL $p
        fi
    done
}

slam_tomb() {
    # $1 = tomb mount point
    local pidk

    pidk=`lsof -t "$1"`
    if [[ ! -z "$pidk" ]]; then
        kill_tomb "$pidk" "soft"
    else
        return 0
    fi

    # if there are remaining pids
    # we need to play hard    
    pidk=`lsof -t "$1"`
    if [[ -z "$pidk" ]]; then
        return 0
    fi

    # if we set the -f (force) option
    # don't wait, just kill
    option_is_set -f || sleep 3
    kill_tomb "$pidk" "hard"
    pidk=`lsof -t "$1"`
    if [[ -z "$pidk" ]]; then
        return 0
    fi

    # if there are still some pids around
    # we have to kill 'em all
    option_is_set -f || sleep 3
    kill_tomb "$pidk" "must die"
    pidk=`lsof -t "$1"`
    if [[ -z "$pidk" ]]; then
        return 0
    fi

    # what PITA!
    return 1
}

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

    if ! [ $1 ]; then
	    tombs=`find /dev/mapper -name 'tomb.*'`
	    how_many_tombs=`wc -w <<< "$tombs"`
	    if [[ "$how_many_tombs" == "0" ]]; then
	        error "There is no open tomb to be closed"
	        return 1
	    elif [[ "$how_many_tombs" == "1" ]]; then
	        #mapper=`find /dev/mapper -name 'tomb.*'`
	        func "closing mapper $tombs"
	        umount_tomb ${tombs}
	        return 1
	    else
	        error "Too many tombs mounted, please specify which to unmount:"
	        ls /dev/mapper/tomb.*
	        error "or issue the command 'tomb close all' to clos'em all."
	        return 1
	    fi
    fi

    if [ "$1" = "all" ]; then
	    tombs=`find /dev/mapper -name 'tomb.*'`
	    if ! [ $tombs ]; then
	        notice "Tombs are all closed, cemetery is quiet."
	        return 0
	    fi
	    for t in ${(f)tombs}; do
	        umount_tomb ${t}
	    done
	    return 0
    fi


    # tomb close argument deduction
    pathmap=`dirname "$1"`

    if [ "${pathmap}" = "/dev/mapper" ]; then
	    mapper="$1" # argument is the mapper (or none which autofills mapper)
	    tombname="`print $mapper | cut -d. -f2`"
	    tombmount=`mount -l | \
	    awk -vtomb="[$tombname]" '/^\/dev\/mapper\/tomb/ { if($7==tomb) print $3 } '`
    elif [ "$pathmap" = "." ]; then
	    tombname="$1" # argument is the name
	    mapper=`mount -l | \
	    awk -vtomb="[$tombname]" '/^\/dev\/mapper\/tomb/ { if($7==tomb) print $1 } '`
	    tombmount=`mount -l | \
	    awk -vtomb="[$tombname]" '/^\/dev\/mapper\/tomb/ { if($7==tomb) print $3 } '`
    else
	    tombmount="$1" # argument should be the mount
    	mapper=`mount | awk -vmnt="$tombmount" '/^\/dev\/mapper\/tomb/ { if($3==mnt) print $1 }'`
	    tombname="`print $mapper | cut -d. -f2`"
    fi

    # avoid block when the same tomb is mounted, take only the first
    for tm in ${(f)tombmount}; do tombmount=${tm}; break; done

    func "tomb close argument: $1"
    func "name:\t$tombname"
    func "mount:\t$tombmount"
    func "mapper:\t$mapper"

    if ! [ -e "$mapper" ]; then
	error "Tomb not found: $1"
	error "Please specify an existing tomb."
	return 0
    fi

    if [ $SLAM ]; then
	    notice "Slamming tomb $tombname mounted on $tombmount"
	    act "Kill all processes busy inside the tomb"
        slam_tomb "$tombmount"
        if [[ $? == 1 ]]; then
            error "Cannot slam the tomb $tombname"
            return 1
        fi
    else
	    notice "Closing tomb $tombname mounted on $tombmount"
    fi

    # check if there are binded dirs and close them
    tombmount_esc=`sed 's:\/:\\\/:g' <<< $tombmount `
    unbind=`mount | awk "/^$tombmount_esc.*bind/"' { print $3 }'`
    for b in ${(f)unbind}; do
	    hook="`basename $b`"
	    act "closing tomb hook: $hook"
	    umount $b
	    if [[ $? != 0 ]]; then
	        if [ $SLAM ]; then
		        notice "Slamming tomb: killing all processes using this hook"
                slam_tomb "$b"
                if [[ $? == 1 ]]; then
                    error "Cannot slam the tomb $b"
                    return 1
                fi
		        umount $b
            else
		        error "Tomb hook is busy, cannot close tomb."
		        return 1
	        fi
	    fi
    done

    # Execute post-hooks for eventual cleanup
    if ! [ $NOBIND ]; then
	    exec_safe_post_hooks ${tombmount%%/} close
    fi

    if [ $tombmount ]; then # tomb is actively mounted
	func "performing umount of $tombmount"
	umount ${tombmount}
	if ! [ $? = 0 ]; then
	    error "Tomb is busy, cannot umount!"
	else
	    rmdir ${tombmount}
	fi
    fi

    cryptsetup luksClose $mapper
    if ! [ $? = 0 ]; then
	error "error occurred in cryptsetup luksClose ${mapper}"
	return 1
    fi

    loopdev=`cut -d '.' -f4 <<< "$mapper"`
    losetup -d "/dev/$loopdev"

    # kill the status tray widget if still present
    # this makes the widget disappear when closing tomb from cli
    awkmapper=`sed 's:\/:\\\/:g' <<< $mapper`
    statustray_pid=`ps ax | awk "/tomb-status $awkmapper/"' {print $1} '`
    if [ ${statustray_pid} ]; then
	kill ${statustray_pid}
    fi

    notice "Tomb $tombname closed: your bones will rest in peace."
    return 0
}

# list all tombs mounted in a readable format
list_tombs() {
    if [ $1 ]; then
	# list a specific tomb
	mounted_tombs=`mount -l |
    awk -vtomb="[$1]" '/^\/dev\/mapper\/tomb/ { if($7==tomb) print $1 ";" $3 ";" $5 ";" $6 ";" $7 }'`
    else
	# list all open tombs
	mounted_tombs=`mount -l |
    awk '/^\/dev\/mapper\/tomb/ { print $1 ";" $3 ";" $5 ";" $6 ";" $7 }'`
    fi
    # 1 = full mapper path
    # 2 = mountpont
    # 3 = filesystem
    # 4 = mount options
    # 5 = name

    if ! [ $mounted_tombs ]; then
	if [ $1 ]; then
	    error "There seems to be no open tomb engraved as [${1}]"
	else
	    error "I can't see any open tomb, may they all rest in peace."
	fi
	exit 1
    fi

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

	tombname=${t[(ws:;:)5]}
	tombmount=${t[(ws:;:)2]}
	tombfs=${t[(ws:;:)3]}
	tombfsopts=${t[(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%%%}
	tombsince=`date --date=@${mapper[(ws:.:)3]} +%c`

	# breaking up such strings is good for translation
	print -n "$fg[green]$tombname"
	print -n "$fg[white] open on "
	print -n "$fg_bold[white]$tombmount"
	print -n "$fg_no_bold[white] using "
	print "$fg_bold[white]$tombfs $tombfsopts"

	print -n "$fg_no_bold[green]$tombname"
	print -n "$fg[white] size "
	print -n "$fg_bold[white]$tombtot"
	print -n "$fg_no_bold[white] of which "
	print -n "$fg_bold[white]$tombused"
	print -n "$fg_no_bold[white] used "
	print -n "$fg_bold[white]$tombavail"
	print -n "$fg_no_bold[white] free ("
	print -n "$fg_bold[white]$tombpercent"
	print "$fg_no_bold[white] full)"
    
    if [[ ${tombp} -ge 90 ]]; then
        error "Your tomb is almost full!"
    fi

	print -n "$fg_no_bold[green]$tombname"
	print -n "$fg_no_bold[white] open since "
	print "$fg_bold[white]$tombsince$fg_no_bold[white]"
	
	# now check hooks
	mtomb=`sed 's:\/:\\\/:g' <<< $tombmount`
	mounted_hooks=`mount | awk "/^$mtomb/"' {print $1 ";" $3}'`
	for h in ${(f)mounted_hooks}; do
	    print -n "$fg[green]$tombname"
	    print -n "$fg_no_bold[white] hooks "
	    print -n "$fg_bold[white]`basename ${h[(ws:;:)1]}`"
	    print -n "$fg_no_bold[white] on "
	    print "$fg_bold[white]${h[(ws:;:)2]}$fg_no_bold[white]"
	done
    done
}

launch_status() {
    # calculates the correct arguments to launch tomb-status tray
    # applet; it takes the tomb name as an argument and can be
    # launched after a successful tomb mount.

    which tomb-status > /dev/null
    if [ $? != 0 ]; then
	error "Cannot find tomb-status binary, operation aborted."
	return 1
    fi

    if ! [ $DISPLAY ]; then
	error "No active X display found, operation aborted."
	error "Status launches a graphical tray applet, you need X running."
	return 1
    fi

    # check argument. use single tomb mounted if no argument
    # abort if more than one tomb is mounted.
    if ! [ $1 ]; then
	tombs=`find /dev/mapper -name 'tomb.*'`
	how_many_tombs=`wc -w <<< "$tombs"`
	if [[ "$how_many_tombs" == "0" ]]; then
	    error "There is no open tomb, status cannot be launched"
	    return 1
	elif [[ "$how_many_tombs" == "1" ]]; then
	        #mapper=`find /dev/mapper -name 'tomb.*'`
	    tombname=`find /dev/mapper -name "tomb.*"`
	    tombname=`basename $tombname | cut -d. -f2`
	    notice "launching status for tomb $tombname"
	else
	    error "Too many tombs mounted, please specify which one"
	    list_tombs
	    return 0
	fi
    else
	# name was specified on command line
	tombname=$1
	ls /dev/mapper | grep "^tomb.${tombname}.*" > /dev/null
	if [ $? != 0 ]; then
	    error "Cannot find any tomb named $tombname being open, operation aborted."
	    return 1
	fi
    fi

    # finally we launch
    tombmap=`mount -l | awk "/\[${tombname}\]$/"' { print $1 } '`
    tombmount=`mount -l | awk "/\[${tombname}\]$/"' { print $3 } '`
    tomb-status $tombmap $tombname $tombmount &!
    return 0
}

# install mime-types, bells and whistles for the desktop
# see http://developers.sun.com/solaris/articles/integrating_gnome.html
# and freedesktop specs
install_tomb() {

# TODO: distro package deps (for binary)
# debian: zsh, cryptsetup, sudo
    act "updating mimetypes..."
    cat <<EOF > /tmp/dyne-tomb.xml
<?xml version="1.0"?>
<mime-info xmlns='http://www.freedesktop.org/standards/shared-mime-info'>
  <mime-type type="application/x-tomb-volume">
    <comment>Tomb encrypted volume</comment>
    <glob pattern="*.tomb"/>
  </mime-type>
  <mime-type type="application/x-tomb-key">
    <comment>Tomb crypto key</comment>
    <glob pattern="*.tomb.key"/>
  </mime-type>
</mime-info>
EOF
    xdg-mime install /tmp/dyne-tomb.xml
    xdg-icon-resource install --context mimetypes --size 32 monmort.xpm monmort
    xdg-icon-resource install --size 32 monmort.xpm dyne-monmort

    rm /tmp/dyne-tomb.xml

    act "updating desktop..."
    cat <<EOF > /usr/share/applications/tomb.desktop
[Desktop Entry]
Version=1.0
Type=Application
Name=Tomb crypto undertaker
GenericName=Crypto undertaker
Comment=Keep your bones safe
Exec="${TOMBOPENEXEC}" %U
TryExec=tomb-open
Icon=monmort.xpm
Terminal=true
Categories=Utility;Security;Archiving;Filesystem;
MimeType=application/x-tomb-volume;
X-AppInstall-Package=tomb
EOF
	update-desktop-database

    act "updating menus..."
    cat <<EOF > /etc/menu/tomb
?package(tomb):command="tomb" icon="/usr/share/pixmaps/monmort.xpm" needs="text" \
	section="Applications/Accessories" title="Tomb" hints="Crypto" \
	hotkey="Tomb"
EOF
    update-menus

    act "updating mime info..."
    cat <<EOF > /usr/share/mime-info/tomb.keys
# actions for encrypted tomb storage
application/x-tomb-volume:
	open="${TOMBOPENEXEC}" %f
	view=tomb-open %f
	icon-filename=monmort.xpm
	short_list_application_ids_for_novice_user_level=tomb
EOF
    cat <<EOF > /usr/share/mime-info/tomb.mime
# mime type for encrypted tomb storage
application/x-tomb-volume
	ext: tomb

application/x-tomb-key
	ext: tomb.key
EOF
    cat <<EOF > /usr/lib/mime/packages/tomb
application/x-tomb-volume; tomb-open '%s'; priority=8
EOF
    update-mime

    act "updating application entry..."

    cat <<EOF > /usr/share/application-registry/tomb.applications
tomb
	 command=tomb-open
	 name=Tomb - Crypto Undertaker
	 can_open_multiple_files=false
	 expects_uris=false
	 requires_terminal=true
	 mime-types=application/x-tomb-volume,application/x-tomb-key
EOF
    act "Tomb is now installed."
}

option_is_set() {
    #First argument, the option (something like "-s")
    #Second (optional) argument: if it's "out", command will print it out 'set'/'unset'
    #                       This is useful for if conditions
    #Return 0 if is set, 1 otherwise
    [[ -n ${(k)opts[$1]} ]];
    r=$?
    if [[ $2 == out ]]; then
        if [[ $r == 0 ]]; then
            echo 'set'
        else
            echo 'unset'
        fi
    fi
    return $r;
}
option_value() {
    #First argument, the option (something like "-s")
    <<< ${opts[$1]}
}

main() {
    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:
    # 1. An option CAN'T have differente meanings/behaviour in different subcommands.
    #    For example, "-s" means "size" and accept an argument. If you are tempted to add
    #    an option "-s" (that means, for example "silent", and doesn't accept an argument)
    #              DON'T DO IT!
    #     There are two reasons for that:
    #       I. usability; user expect that "-s" is "size
    #       II. Option parsing WILL EXPLODE if you do this kind of bad things
    #               (it will say "option defined more than once, and he's right)
    main_opts=(q -quiet=q D -debug=D h -help=h v -version=v)
    subcommands_opts[__default]=""
    subcommands_opts[open]="n -nohook=n k: -key=k o: -mount-options=o -ignore-swap"
    subcommands_opts[mount]=${subcommands_opts[open]}
    subcommands_opts[create]="s: -size=s -ignore-swap k: -key=k"
    subcommands_opts[close]=""
    subcommands_opts[help]=""
    subcommands_opts[slam]=""
    subcommands_opts[list]=""
    subcommands_opts[help]=""
    subcommands_opts[bury]=""
    subcommands_opts[exhume]=""
    subcommands_opts[decompose]=""
    subcommands_opts[recompose]=""
    subcommands_opts[install]=""
    subcommands_opts[askpass]=""
    subcommands_opts[mktemp]=""
    subcommands_opts[source]=""
    subcommands_opts[status]=""
    ### 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)
    zparseopts -M -E -D -Adiscardme ${every_opts}
    unset discardme
    subcommand=$1
    if [[ -z $subcommand ]]; then
        subcommand="__default"
    fi
    if [[ -z ${(k)subcommands_opts[$subcommand]} ]]; then #there's no such subcommand
        error "Subcommand '$subcommand' doesn't exist"
        exit 127
    fi
    argv=(${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 [[ -n $cmd_opts ]]; then #if there is no option, we don't need parsing
        zparseopts -M -E -D -Aopts ${cmd_opts}
	if [[ $? != 0 ]]; then
	  error "Some error occurred during option processing. See \"tomb help\" for more info"
	  exit 127
	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 shouldnt be appended to PARAM
	elif [[ $arg[1] == '-'  ]]; then
	  if [[ $ok == 0 ]]; then
		error "unrecognized option $arg"
		exit 127
	  fi
	fi
	PARAM+=$arg
  done
  #first parameter actually is the subcommand: delete it and shift
  if [[ $subcommand != '__default' ]]; then
      PARAM[1]=()
      shift
  fi
  ### End parsing command-specific options

  ### Set global options (useless, but for code retro-compatibility)
  for opt in ${(k)global_opts}; do
	if [[ $opt == '-q' ]]; then
	  QUIET=1
	elif [[ $opt == '-D' ]]; then
        DEBUG=1
	fi
  done

  CMD=$subcommand
  CMD2=$PARAM[1]
  CMD3=$PARAM[2]

    func "Tomb command: $CMD $CMD2 $CMD3"

    case "$subcommand" in
	 create) check_priv ; create_tomb ;;
	  mount) check_priv ; mount_tomb  ;;
	   open) check_priv ; mount_tomb  ;;
	 umount) check_priv ; umount_tomb ${CMD2} ;;
	  close) check_priv ; umount_tomb ${CMD2} ;;
	   slam) check_priv ; SLAM=1; umount_tomb ${CMD2} ;;
	   list) list_tombs ${CMD2} ;;
	 status) launch_status ${CMD2} ;;
	   help) usage ;;
	   bury) if [ "$STEGHIDE" = 0 ]; then
		    error "steghide not installed. Cannot bury your key"
		    return 1
		 fi
		 encode_key ${CMD2} ${CMD3} ;;
	 exhume) if [ "$STEGHIDE" = 0 ]; then
 		    error "steghide not installed. Cannot exhume your key"
		    return 1
		 fi
		 decode_key ${CMD2} ;;
	# internal commands useful to developers
       'source') return 0 ;;
	install) check_priv ; install_tomb ;;
	askpass) ask_password $CMD2 ;;
	 mktemp) safe_dir ${CMD2} ;;
      translate) generate_translatable_strings ;;
      __default)
          if option_is_set -v; then
            echo Tomb - $VERSION
        else
          usage
      fi;;
	      *) error "command \"$CMD\" not recognized"
		 act "try -h for help"
		 return 1
		 ;;
    esac
    return 0
}

check_bin
main $@