Tomb/tomb

#!/bin/zsh
#
# Tomb, the Crypto Undertaker
#
# A commandline tool to easily operate encryption of secret data
#
# Homepage on: [tomb.dyne.org](http://tomb.dyne.org)

# {{{ License

# Copyright (C) 2007-2014 Dyne.org Foundation
#
# Tomb is designed, written and maintained by Denis Roio <jaromil@dyne.org>
#
# With contributions by Anathema, Boyska and Hellekin O. Wolf.
#
# Testing and reviews are contributed by Dreamer, Shining,
# Mancausoft, Asbesto Molesto and Nignux.
#
# Tomb's artwork is contributed by Jordi aka Mon Mort.

#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.

# }}} - License

# {{{ Global variables

VERSION=1.5.3
DATE="Jun/2014"
TOMBEXEC=$0
typeset -a OLDARGS
for arg in ${argv}; do OLDARGS+=($arg); done
DD="dd"
WIPE="rm -f"
MKFS="mkfs.ext3 -q -F -j -L"
KDF=1
STEGHIDE=1
MKTEMP=1
RESIZER=1
SWISH=1
QRENCODE=1
MOUNTOPTS="rw,noatime,nodev"

typeset -A global_opts
typeset -A opts
typeset -h username

typeset -h _uid
typeset -h _gid
typeset -h _tty

typeset -H tomb_secret

# Make sure sbin is in PATH
PATH+=:/sbin:/usr/sbin

# For gettext
export TEXTDOMAIN=tomb

# }}}

# {{{ Safety functions

endgame() {
    # here clear all temp files and flush all pipes
    _verbose "Signal trap: $1"
    unset tomb_secret
}

# 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  }

_have_shm() {
    # Check availability of 1MB of SHM
    _verbose "_have_shm 0 We need only 1 MB of RAM."
    [[ -k /dev/shm ]] || return 1

    local -i SHM RAM

    SHM=$(df -k -B 4K -a -t tmpfs /dev/shm | awk '/\/dev\/shm/ { print $4; }')
    (( $? )) && return 1
    _verbose "_have_shm 1 SHM $SHM KB are available."

    RAM=$(awk '/MemFree/ { print $2 }' /proc/meminfo)
    _verbose "_have_shm 2 RAM $RAM KB are free."
    (( $RAM >= 1024 )) && return 0

    _verbose "_have_shm 3 RAM $RAM KB left only :("
    # Now we have more RAM than affected to SHM, so we can expect some for our little needs.
    # Does that work when SHM is disabled from kernel config?
    return 1
}

# Create temporary directories with caution
safe_dir() {
    # Try and create our temporary directory in RAM
    # Note that there's no warranty the underlying FS won't swap
    # every 5 seconds (e.g., ext3)
    local -i tries
    while (( $tries < 3 )) ; do
        tries+=1
        if _have_shm; then
            _verbose "safe_dir creating $1 dir in RAM."
            if (( $MKTEMP )); then
                mktemp -d /dev/shm/tomb.$1.$$.XXXXXXX
            else
                dir="/dev/shm/tomb.$1.$$.$RANDOM$RANDOM"
                mkdir -m 0700 -p "$dir"
                print "$dir"
            fi
            return 0
        else
            _warning "WARNING: we cannot ensure we're running in RAM."
            _verbose "Wait a bit before retrying... (attempt $tries)."
            sync && sleep 0.5
        fi
    done
    _warning "WARNING: no RAM available for me to run safely."
    return 1
}

# Provide a random filename in shared memory
safe_filename() {
    _have_shm || _failure "No access to shared memory on this system, sorry."
    (( $MKTEMP )) && \
        mktemp -u /dev/shm/tomb.$1.$$.XXXXXXX || \
        print "/dev/shm/tomb.$1.$$.$RANDOM$RANDOM"
}

# Check if swap is activated
check_swap() {
    # Return 0 if NO swap is used, 1 if swap is used
    # Return 2 if swap(s) is(are) used, but ALL encrypted
    local swaps="$(awk '/^\// { print $1 }' /proc/swaps 2>-)"
    [[ -z "$swaps" ]] && return 0                # No swap partition is active
    # Check whether all swaps are encrypted, and return 2
    # If any of the swaps is not encrypted, we bail out and return 1.
    ret=1
    for s in $=swaps; do
        bone=`sudo file $s`
        if `echo "$bone" | grep 'swap file' &>-`; then
            # It's a regular (unencrypted) swap file
            ret=1
            break
        elif `echo "$bone" | grep 'symbolic link' &>-`; then
            # Might link to a block
            ret=1
            if [ "/dev/mapper" = "${s%/*}" ]; then
                is_crypt=`sudo dmsetup status "$s" | awk '/crypt/ {print $3}'`
                if [ "crypt" = "$is_crypt" ]; then
                    ret=2
                fi
            else
                break
            fi
        elif `echo "$bone" | grep 'block special' &>-`; then
            # Is a block
            ret=1
            is_crypt=`sudo dmsetup status "$s" | awk '/crypt/ {print $3}'`
            if [ "crypt" = "$is_crypt" ]; then
                ret=2
            else
                break
            fi
        fi
    done
    _warning  "An active swap partition is detected, this poses security risks."
    if [[ $ret -eq 2 ]]; then
        _success "All your swaps are belong to crypt.  Good."
    else
        _warning  "You can deactivate all swap partitions using the command:"
        _warning  " swapoff -a"
        _warning  "But if you want to proceed like this, use the -f (force) flag."
        _failure "Operation aborted."
    fi
    return $ret
}

# Wrapper to allow encrypted swap and remind the user about
# possible data leaks to disk if swap is on, and not to be ignored
_check_swap() {
    if ! option_is_set -f && ! option_is_set --ignore-swap; then
        check_swap
        case $? in
            0|2)     # No, or encrypted swap
                return 0
                ;;
            *)       # Unencrypted swap
                return 1
                ;;
        esac
    fi
}

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

    # 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

    title="Insert tomb password."
    if [ $2 ]; then title="$2"; fi

    output=`cat <<EOF | GTK2_RC_FILES=${GTK2_RC} pinentry 2>- | tail -n +7
OPTION ttyname=$TTY
OPTION lc-ctype=$LANG
SETTITLE $title
SETDESC $1
SETPROMPT Password:
GETPIN
EOF`
    if [[ `tail -n1 <<<$output` =~ ERR ]]; then
        return 1
    fi
    head -n1 <<<$output | awk '/^D / { sub(/^D /, ""); print }'
    return 0
}

# Drop privileges
exec_as_user() {
    if ! [ $SUDO_USER ]; then
        exec $@[@]
        return $?
    fi
    _verbose "exec_as_user '$SUDO_USER': ${(f)@}"
    sudo -u $SUDO_USER "${@[@]}"
    return $?
}

#Escalate privileges
check_priv() {
    # save original user
    username=$USER
    if [ $UID != 0 ]; then
        _verbose "Using sudo for root execution of '${TOMBEXEC} ${(f)OLDARGS}'."
        # check if sudo has a timestamp active
        sudok=false

        if ! option_is_set --sudo-pwd; then
            if [ $? != 0 ]; then # if not then ask a password
                cat <<EOF | pinentry 2>- | awk '/^D / { sub(/^D /, ""); print }' | sudo -S -v
OPTION ttyname=$TTY
OPTION lc-ctype=$LANG
SETTITLE Super user privileges required
SETDESC Sudo execution of Tomb ${OLDARGS[@]}
SETPROMPT Insert your USER password:
GETPIN
EOF
            fi
        else
            _verbose "Escalating privileges using sudo-pwd."
            sudo -S -v <<<`option_value --sudo-pwd`
        fi
        sudo "${TOMBEXEC}" -U ${UID} -G ${GID} -T ${TTY} "${(@)OLDARGS}"
        exit $?
    fi # are we root already

    # check if we have support for loop mounting
    losetup -f >-
    { test "$?" = "0" } || {
        _warning "Loop mount of volumes is not supported 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 at this conditions."
        _failure "Operation aborted."
    }

    # make sure necessary kernel modules are loaded
    modprobe dm_mod 2>-
    modprobe dm_crypt 2>-

    return 0
}

# check if a filename is a valid tomb
is_valid_tomb() {
    _verbose "is_valid_tomb $1"
    # argument check
    { test "$1" = "" } && {
        _warning "Tomb file is missing from arguments."; return 1 }
    # file checks
    { test -r "$1" } || {
        _warning "Tomb file not found: $1"; return 1 }
    { test -f "$1" } || {
        _warning "Tomb file is not a regular file: $1"; return 1 }
    # check file type (if its a Luks fs)
    file "$1" | grep -i 'luks encrypted file' >-
    { test $? = 0 } || {
        _warning "File is not a valid tomb: $1"; return 1 }
    # check if its already open
    tombfile=`basename $1`
    tombname=${tombfile%%\.*}
    mount -l | grep "${tombfile}.*\[$tombname\]$" >-
    { test $? = 0 } && {
        _warning "Tomb is currently in use: $tombname"; return 1 }
    _message "Valid tomb file found: $1"
    return 0
}

# }}}

# {{{ Commandline interaction

usage() {
    cat <<EOF

Syntax: tomb [options] command [arguments]

Commands:

 // Creation:
 dig     create a new empty TOMB file of size -s in MB
 forge   create a new KEY file and set its password
 lock    installs a lock on a TOMB to use it with KEY

 // Operations on tombs:
 open    open an existing TOMB
 index   update the search indexes of tombs
 search  looks for filenames matching text patterns
 list    list of open TOMBs and information on them
 close   close a specific TOMB (or 'all')
 slam    slam a TOMB killing all programs using it
EOF
    if [ "$RESIZER" = 1 ]; then
        cat <<EOF
 resize  resize a TOMB to a new size -s (can only grow)
EOF
    fi
cat <<EOF

 // Operations on keys:
 passwd  change the password of a KEY
 setkey  change the KEY locking a TOMB (needs old one)
EOF

    { test "$QRENCODE" = "1" } && {
        cat <<EOF
 engrave makes a QR code of a KEY to be saved on paper
EOF
    }

    if [ "$STEGHIDE" = 1 ]; then
        cat <<EOF
 bury    hide a KEY inside a JPEG image
 exhume  extract a KEY from a JPEG image
EOF
    fi
    cat <<EOF

Options:

 -s     size of the tomb file when creating/resizing one (in MB)
 -k     path to the key to be used ('-k -' to read from stdin)
 -n     don't process the hooks found in tomb
 -o     mount options used to open (default: rw,noatime,nodev)
 -f     force operation (i.e. even if swap is active)
EOF
    { test "$KDF" = 1 } && {
        cat <<EOF
 --kdf  generate passwords armored against dictionary attacks
EOF
    }

cat <<EOF

 -h     print this help
 -v     print version, license and list of available ciphers
 -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://github.com/dyne/tomb/issues>.
EOF
}


# Check an option
option_is_set() {
    # First argument, the commandline flag (i.e. "-s").
    # Second (optional) argument: if "out", command will print it out 'set'/'unset'
    # (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;
}

# Get an option value
option_value() {
    # First argument, the commandline flag (i.e. "-s").
    <<< ${opts[$1]}
}

# Messaging function with pretty coloring
function _msg() {
    local msg="$(gettext -s "$2")"
    local command="print -P"
    local progname="$fg[magenta]${TOMBEXEC##*/}$reset_color"
    local message="$fg_bold[normal]$fg_no_bold[normal]$msg$reset_color"
    local -i returncode

    case "$1" in
        inline)
            command+=" -n"; pchars=" > "; pcolor="yellow"
            ;;
        message)
            pchars=" . "; pcolor="white"; message="$fg_no_bold[$pcolor]$msg$reset_color"
            ;;
        verbose)
            pchars="[D]"; pcolor="blue"
            ;;
        success)
            pchars="(*)"; pcolor="green"; message="$fg_no_bold[$pcolor]$msg$reset_color"
            ;;
        warning)
            pchars="[W]"; pcolor="yellow"; message="$fg_no_bold[$pcolor]$msg$reset_color"
            ;;
        failure)
            pchars="[E]"; pcolor="red"; message="$fg_no_bold[$pcolor]$msg$reset_color"
            returncode=1
            ;;
        *)
            pchars="[F]"; pcolor="red"
            message="Developer oops!  Usage: _msg MESSAGE_TYPE \"MESSAGE_CONTENT\""
            returncode=127
            ;;
    esac
    ${=command} "${progname} $fg_bold[$pcolor]$pchars$reset_color ${message}$color[reset_color]" >&2
    return $returncode
}

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

function _verbose xxx() {
    option_is_set -D && _msg verbose "$1"
    return 0
}

function _success yes() {
    option_is_set -q || _msg success "$1"
    return 0
}

function _warning  no() {
    option_is_set -q || _msg warning "$1"
    return 1
}

function _failure die() {
    typeset -i exitcode=${2:-1}
    option_is_set -q || _msg failure "$1"
    # be sure we forget the secrets we were told
    unset tomb_secret
    exit $exitcode
}

# Print out progress to inform GUI caller applications (--batch mode)
progress() {
    #      $1 is "what is progressing"
    #      $2 is "percentage"
    #      $3 is (eventually blank) status
    #      Example: if creating a tomb, it could be sth like
    #          progress create 0 filling with random data
    #          progress create 40 generating key
    #          progress keygen 0 please move the mouse
    #          progress keygen 30 please move the mouse
    #          progress keygen 60 please move the mouse
    #          progress keygen 100 key generated
    #          progress create 80 please enter password
    #          progress create 90 formatting the tomb
    #          progress create 100 tomb created successfully
    if ! option_is_set --batch; then
        return
    fi
    print "[m][P][$1][$2][$3]" >&2

}

# Check what's installed
check_bin() {
    # check for required programs
    for req in cryptsetup pinentry sudo gpg; do
        command -v $req >- || _failure "Cannot find $req. It's a requirement to use Tomb, please install it." 1
    done

    export PATH=/sbin:/usr/sbin:$PATH

    # which dd command to use
    command -v dcfldd >-
    { test $? = 0 } && { DD="dcfldd statusinterval=1" }

    # which wipe command to use
    command -v wipe >- && WIPE="wipe -f -s" || WIPE="rm -f"

    # check for filesystem creation progs
    command -v mkfs.ext4 >- && \
        MKFS="mkfs.ext4 -q -F -j -L" || \
        MKFS="mkfs.ext3 -q -F -j -L"

    # check for mktemp
    command -v mktemp >- || MKTEMP=0
    # check for steghide
    command -v steghide >- || STEGHIDE=0
    # check for resize
    command -v e2fsck resize2fs >- || RESIZER=0
    # check for KDF auxiliary tools
    command -v tomb-kdb-pbkdf2 >- || KDF=0
    # check for Swish-E file content indexer
    command -v swish-e >- || SWISH=0
    # check for QREncode for paper backups of keys
    command -v qrencode >- || QRENCODE=0
}

# }}} - Commandline interaction

# {{{ Key operations

# This function retrieves a tomb key specified on commandline or from
# stdin if -k - was selected.  It also runs validity checks on the
# file. Callers should always use drop_key() when done with all key
# operations.  On success returns 0 and prints out the full path to
# the key.
load_key() {
    # take the name of a tomb file as argument to option -k
    # if no argument is given, tomb{key|dir|file} are set by caller

    { option_is_set -k } || {
        _failure "This operation requires a key file to be specified using the -k option."
        return 1 }

    local keyopt
    keyopt="`option_value -k`"

    if [[ "$keyopt" == "-" ]]; then
        _verbose "load_key reading from stdin."
        # take key from stdin
        tombkeydir=`safe_dir load_key_stdin`
        # tombkeydir is a global used to check if key from stdin
        _verbose "tempdir is $tombkeydir"
        act "Waiting for the key to be piped from stdin... "
        cat > ${tombkeydir}/stdin.tmp.key
        print ok >&2
        tombdir=${tombkeydir}
        tombfile=stdin.tmp.key
        tombname="stdin"
    elif [[ "$keyopt" != "" ]]; then
        _verbose "load_key argument: `option_value -k`"
        # take key from a file
        tombkey=`option_value -k`
        tombdir=`dirname $tombkey`
        tombfile=`basename $tombkey`
    fi

    tombkey=${tombdir}/${tombfile}

    _verbose "load_key: ${tombkey}"
    { test -r "${tombkey}" } || {
        _warning "Key not found, specify one using -k."
        drop_key
        return 1 }

    # TODO: move this condition for JPEG steg into is_valid_key
    [[ `file "$tombkey"` =~ "JP.G" ]] || {
        # if the key file is an image don't check file header
        if ! is_valid_key ${tombkey}; then
            _warning "The key seems invalid or its format is not known by this version of Tomb."
            drop_key
            return 1
        fi
    }

    print "$tombkey"
    return 0
}

# takes two args just like get_lukskey
# prints out the decrypted content
# contains tweaks for different gpg versions
gpg_decrypt() {
    # fix for gpg 1.4.11 where the --status-* options don't work ;^/
    gpgver=`gpg --version --no-permission-warning | awk '/^gpg/ {print $3}'`
    local lukspass="$1"
    local keyfile="$2"

    if [ "$gpgver" = "1.4.11" ]; then
        _verbose "GnuPG is version 1.4.11 - adopting status fix."

        tomb_secret=`print "$lukspass" | \
            gpg --batch --passphrase-fd 0 --no-tty --no-options \
            -d "${keyfile}"`
        ret=$?
        unset lukspass

    else # using status-file in gpg != 1.4.11

        res=`safe_filename lukskey`
        [[ $? = 0 ]] || {
            unset lukspass;
            _failure "Fatal error creating temp file." }

        tomb_secret=`print "$lukspass" | \
            gpg --batch --passphrase-fd 0 --no-tty --no-options \
            --status-fd 2 --no-mdc-warning --no-permission-warning \
            --no-secmem-warning -d "${keyfile}" 2> $res`

        unset lukspass
        grep 'DECRYPTION_OKAY' $res >-
        ret=$?; rm -f $res

    fi
    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, $2 is the keyfile

    local lukspass="$1"
    local keyfile="$2"
    local exhumedkey

    firstline=`head -n1 $keyfile`
    _verbose "get_lukskey XXX $keyfile"

    # key is KDF encoded
    if [[ $firstline =~ '^_KDF_' ]]; then
        _verbose "KDF: `cut -d_ -f 3 <<<$firstline`"
        case `cut -d_ -f 3 <<<$firstline` in
            pbkdf2sha1)
                pbkdf2_param=`cut -d_ -f 4- <<<$firstline | tr '_' ' '`
                lukspass=$(tomb-kdb-pbkdf2 ${=pbkdf2_param} 2>- <<<$lukspass)
                ;;
            *)
                _failure "No suitable program for KDF `cut -f 3 <<<$firstline`."
                unset lukspass
                return 1
                ;;
        esac

    # key needs to be exhumed from an image
    elif [[ `file "$keyfile"` =~ "JP.G" ]]; then
        exhumedkey="`safe_filename exhumedkey`"
        exhume_key "$keyfile" "$lukspass" "$exhumedkey"
        keyfile="$exhumedkey"
    fi

    # check validity, eventually repair adding headers
    is_valid_key "$keyfile" || {
        _failure "This key is unusable: $keyfile" }

    # saves decrypted content into $tomb_secret
    gpg_decrypt "$lukspass" "$keyfile"
    ret="$?"

    { test "$exhumedkey" = "" } || { ${=WIPE} "$exhumedkey" }

    _verbose "get_lukskey returns $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 prints
# the password (be careful about where you save it!)
ask_key_password() {
    local tombkey="$1"
    local keyname=`basename $tombkey`
    _message "A password is required to use key ${keyname}"
    local passok=0
    local tombpass=""
    if [ "$2" = "" ]; then
        for c in 1 2 3; do
            if [ $c = 1 ]; then
                tombpass=`exec_as_user ${TOMBEXEC} askpass "Insert password to use key: $keyname"`
            else
                tombpass=`exec_as_user ${TOMBEXEC} askpass "Insert password to use key: $keyname (retry $c)"`
            fi
            if [[ $? != 0 ]]; then
                _warning "User aborted password dialog."
                return 1
            fi

            get_lukskey "$tombpass" "$tombkey"

            if [ $? = 0 ]; then
                passok=1; _message "Password OK."
                break;
            fi
        done

    else
        # if a second argument is present then the password is already known
        tombpass="$2"
        _verbose "ask_key_password with tombpass: $tombpass"

        get_lukskey "$tombpass" "$tombkey"

        if [ $? = 0 ]; then
            passok=1; _message "Password OK."; fi

    fi
    # print the password out in case caller needs to know it
    print "$tombpass"
    unset tombpass
    { test "$passok" = "1" } || { return 1 }
    return 0
}

# change tomb key password
change_passwd() {
    _message "Commanded to change password for tomb key $1"
    _check_swap

    keyfile="`load_key`"

    local tmpnewkey lukskey c tombpass tombpasstmp

    tmpnewkey=`safe_filename passnew`
    lukskey=`safe_filename passold`

    _success "Changing password for $keyfile"


    if option_is_set --tomb-old-pwd; then
        tomb_old_pwd="`option_value --tomb-old-pwd`"
        _verbose "--tomb-old-pwd = $tomb_old_pwd"
        ask_key_password "$keyfile" "$tomb_old_pwd" >-
    else
        ask_key_password "$keyfile" >-
    fi

    { test $? = 0 } || {
        _failure "No valid password supplied." }

    # danger zone in which the key is written in clear

    print "$tomb_secret"> "$lukskey"

    drop_key

    if option_is_set --tomb-pwd; then
        tomb_new_pwd="`option_value --tomb-pwd`"
        _verbose "--tomb-pwd = $tomb_new_pwd"
        gen_key "$lukskey" "$tomb_new_pwd" > "$tmpnewkey"
    else
        gen_key "$lukskey" > "$tmpnewkey"
    fi

    ${=WIPE} "$lukskey"

    if ! is_valid_key "$tmpnewkey"; then
        _failure "Error: the newly generated keyfile does not seem valid."
    else
        # copy the new key as the original keyfile name
        cp -f "${tmpnewkey}" "${keyfile}"
        _success "Your passphrase was successfully updated."

    fi

    _verbose "Cleanup: $tmpnewkey"
    ${=WIPE} "${tmpnewkey}"

}


# To be called after load_key()
drop_key() {
    _verbose "drop_key $tombkey"
    # delete key if temp stored from stdin
    if [[ "$tombkey" =~ "/dev/shm/tomb.load_key_stdin" ]]; then
        { test -r ${tombkey} } && {
            _message "Removing key temporarily stored from stdin"
            ${=WIPE} ${tombkey}; rmdir `dirname ${tombkey}` }
    fi
}

#$1 is the keyfile we are checking
is_valid_key() {
    _verbose "is_valid_key $1"
    # argument check
    { test "$1" = "" } && {
        _warning "Key file is missing from arguments."; return 1 }
    # file checks
    { test -r "$1" } || {
        _warning "Key file not found: $1"; return 1 }
    { test -f "$1" } || {
        _warning "Key file is not a regular file: $1"; return 1 }
    # this header validity check is a virtuosism by Hellekin
    [[ `file =(awk '/^-+BEGIN/,0' $1)` =~ PGP ]] && {
        if [ "$tombkeydir" = "" ]; then _message "Valid key file found: $1"
        else _message "Valid key file passed from stdin"; fi
        return 0 }
    # if no BEGIN header found then we try to recover it
    [[ `file $1 -bi` =~ text/plain ]] && {
        _warning "Key data found with missing headers, attempting recovery."
        local tmp_keyfix=`safe_filename keyfix`
        touch $tmp_keyfix
        # make sure KDF header comes first
        local header=`grep '^_KDF_' $1`
        print "$header" >> $tmp_keyfix
        cat $1 | awk '
BEGIN {
print "-----BEGIN PGP MESSAGE-----"
print
}
/^_KDF_/ { next }
{ print $0 }
END {
print "-----END PGP MESSAGE-----"
}' >> ${tmp_keyfix}
        mv $tmp_keyfix $1
        chown ${_uid}:${_gid} ${1}
        chmod 0600 ${1}
        return 0
    }
    _warning "Invalid key format: $1"
    return 1
}




# takes care to encrypt a key
# honored options: --kdf  --tomb-pwd
gen_key() {
# $1 the lukskey to encrypt
# $2 is the --cipher-algo to use (string taken by GnuPG)
    local lukskey="$1"
    local algopt="`option_value -o`"
    local algo="${algopt:-AES256}"
    # here user is prompted for key password
    local tombpass=""
    local tombpasstmp=""
    local tombpassarg="$2"
    if [ "$tombpassarg" = "" ]; then
        while true; do
            # 3 tries to write two times a matching password
            tombpass=`exec_as_user ${TOMBEXEC} askpass "Type the new password to secure your key"`
            if [[ $? != 0 ]]; then
                _failure "User aborted."
            fi
            if [ -z $tombpass ]; then
                _warning "You set empty password, which is not possible."
                continue
            fi
            tombpasstmp=$tombpass
            tombpass=`exec_as_user ${TOMBEXEC} askpass "Type the new password to secure your key (again)"`
            if [[ $? != 0 ]]; then
                _failure "User aborted."
            fi
            if [ "$tombpasstmp" = "$tombpass" ]; then
                break;
            fi
            unset tombpasstmp
            unset tombpass
        done
    else
        tombpass="$tombpassarg"
        _verbose "gen_key takes tombpass from CLI argument: $tombpass"
    fi

    header=""
    { test "$KDF" = 1 } && {
        { option_is_set --kdf } && {
    # KDF is a new key strenghtening technique against brute forcing
    # see: https://github.com/dyne/Tomb/issues/82
            itertime="`option_value --kdf`"
        # removing support of floating points because they can't be type checked well
            if [[ "$itertime" != <-> ]]; then
                unset tombpass
                unset tombpasstmp
                _failure "Wrong argument for --kdf: must be an integer number (iteration seconds)."
            fi
            # --kdf takes one parameter: iter time (on present machine) in seconds
            local -i microseconds
            microseconds=$(( itertime * 10000 ))
            _success "Using KDF, iterations: $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"
        }
    }


    print -n $header

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

    unset tombpass
    unset tombpasstmp
}

# prints an array of ciphers available in gnupg (to encrypt keys)
list_gnupg_ciphers() {
    # prints an error if GnuPG is not found
    which gpg >- || _failure "gpg (GnuPG) is not found, Tomb cannot function without it."

    ciphers=(`gpg --version | awk '
BEGIN { ciphers=0 }
/^Cipher:/ { gsub(/,/,""); sub(/^Cipher:/,""); print; ciphers=1; next }
/^Hash:/ { ciphers=0 }
{ if(ciphers==0) { next } else { gsub(/,/,""); print; } }
'`)
    echo " ${ciphers}"
    return 1
}

# Steganographic function to bury a key inside an image.
# Requires steghide(1) to be installed
bury_key() {
    tombkey="`load_key`"
    { test "$tombkey" = "" } && {
       _failure "Bury failed: invalid key $tombkey" }

    imagefile=$1

    file $imagefile | grep -i JPEG >-
    if [ $? != 0 ]; then
       _warning "Encode failed: $imagefile is not a jpeg image."
       return 1
    fi

    _success "Encoding key $tombkey inside image $imagefile"
    _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 its not strictly necessary (and having different
    # password would enhance security). Nevertheless here we prefer
    # usability.

    if option_is_set --tomb-pwd; then
        tomb_pwd="`option_value --tomb-pwd`"
        _verbose "--tomb-pwd = $tomb_pwd"
        tombpass=`ask_key_password "$tombkey" "$tomb_pwd"`
    else
        tombpass=`ask_key_password "$tombkey"`
    fi
    { test $? = 0 } || {
        drop_key
        _warning "Wrong password supplied."
        _failure "You shall not bury a key whose password is unknown to you."
    }

    # we omit armor strings since having them as constants can give
    # ground to effective attacks on steganography

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

    unset tombpass
    drop_key

    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() {

    imagefile="$1"
    res=1

    knownpass="$2"

    tombkey="$3"
    [[ "$tombkey" = "" ]] && {
        tombkey="`option_value -k`"
        { test "$tombkey" = "" } && {
            # no key output specified: fallback to stdout
            tombkey="-"
            _message "printing exhumed key on stdout" }
    }

    [[ `file "$imagefile"` =~ "JP.G" ]] || {
        _failure "Encode failed: $imagefile is not a jpeg image." }

    # when a password is passed as argument then always print out
    # the exhumed key on stdout without further checks (internal use)
    { test "$knownpass" = "" } || {
        steghide extract -sf "$imagefile" -p "$knownpass" -xf -
        { test $? = 0 } || {
            _failure "Wrong password or no steganographic key found" }
    }

    { test "$tombkey" = "-" } || {
        if [[ -e "$tombkey" ]]; then
            _warning "File exists: $tombkey"
            { option_is_set -f } || {
                _warning "Make explicit use of --force to overwrite."
                _failure "Refusing to overwrite file. Operation aborted." }
            _warning "Use of --force selected: overwriting."
            rm -f ${tombkey}
        fi
    }

    _message "Trying to exhume a key out of image $imagefile"
    if option_is_set --tomb-pwd; then
        tombpass="`option_value --tomb-pwd`"
        _verbose "--tomb-pwd = $tombpass"
    else
        tombpass=`exec_as_user ${TOMBEXEC} askpass "Insert password to exhume key from $imagefile"`
        if [[ $? != 0 ]]; then
            _warning "User aborted password dialog."
            return 1
        fi
    fi

    # always steghide required
    steghide extract -sf ${imagefile} -p ${tombpass} -xf ${tombkey}
    res=$?

    unset tombpass

    if [ $res = 0 ]; then
        _success "${tombkey} succesfully decoded."
    else
        _warning "Nothing found in $imagefile"
    fi

    return $res
}

# Produces a printable image of the key contents so that it can be
# backuped on paper and hidden in books etc.
engrave_key() {
    # load key from options
    tombkey="`load_key`"
    { test $? = 0 } || { _failure "No key specified." }
    keyname=`basename $tombkey`
    pngname="$keyname.qr.png"

    _success "Rendering a printable QRCode for key: $tombkey"
    # we omit armor strings to save space
    awk '
/^-----/ {next}
/^Version/ {next}
{print $0}' ${tombkey} | qrencode --size 4 --level H \
    --casesensitive -o "$pngname"
    { test $? = 0 } || { _failure "QREncode reported an error." }
    _success "Operation successful:"
    _message "`ls -lh $pngname`"
    _message "`file $pngname`"
    drop_key
}

# }}} - Key handling

# {{{ Create

# This is a new way to create tombs which dissects the whole create_tomb() into 3 clear steps:
#
# * 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)


forge_key() {
    # can be specified both as simple argument or using -k
    local destkey="$1"
    { option_is_set -k } && { destkey="`option_value -k`" }

    { test "$destkey" = "" } && {
        _warning "A filename needs to be specified using -k to forge a new key."
        return 1 }

    _message "Commanded to forge key $destkey"
    _check_swap


    # make sure that gnupg doesn't quits with an error before first run
    { test -r $HOME/.gnupg/pubring.gpg } || {
        mkdir $HOME/.gnupg
        touch $HOME/.gnupg/pubring.gpg }

    { test -r "$destkey" } && {
        _warning "Forging this key would overwrite an existing file. Operation aborted."
        _failure "`ls -lh $destkey`"    }

    # create the keyfile in tmpfs so that we leave less traces in RAM
    local keytmp=`safe_dir forge`
    (( $? )) && _failure "Error creating temp dir."
    _verbose "safe_dir at $keytmp"

    mount tmpfs "${keytmp}" -t tmpfs -o size=1m
    if [ $? != 0 ]; then
        _warning "Cannot mount tmpfs filesystem in volatile memory."
        rm -r "${keytmp}"
        _failure "Operation aborted."
    fi

    local algo
    { option_is_set -o } && { algopt="`option_value -o`" }
    algo=${algopt:-AES256}

    _message "Commanded to forge key $destkey with cipher algorithm $algo"

    local tombkey="$destkey"

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

    touch ${keytmp}/tomb.tmp
    chmod 0600 ${keytmp}/tomb.tmp
    local random_source=/dev/random
    if option_is_set --use-urandom; then
        random_source=/dev/urandom
    fi

    _verbose "Data dump using ${DD[1]} from $random_source"
    ${=DD} bs=1 count=256 if=$random_source of=${keytmp}/tomb.tmp

    if ! [ -r ${keytmp}/tomb.tmp ]; then
        _warning "Cannot generate encryption key."
        umount ${keytmp}
        rm -r $keytmp
        _failure "Operation aborted."
    fi

    _success "Choose the password of your key: ${tombkey}"
    _message "(You can also change it later using 'tomb passwd'.)"
    touch ${tombkey}
    chown ${_uid}:${_gid} ${tombkey}
    chmod 0600 ${tombkey}

    tombname="$tombkey"
    # the gen_key() function takes care of the new key's encryption
    if option_is_set --tomb-pwd; then
        tomb_new_pwd="`option_value --tomb-pwd`"
        _verbose "--tomb-pwd = $tomb_new_pwd"
        gen_key "${keytmp}/tomb.tmp" "$tomb_new_pwd" > "$tombkey"
    else
        gen_key "${keytmp}/tomb.tmp" > "$tombkey"
    fi

    # this does a check on the file header
    if ! is_valid_key ${tombkey}; then
        _warning "The key does not seem to be valid."
        _warning "Dumping contents to screen:"
        cat ${tombkey}
        _warning "--"
        umount ${keytmp}
        rm -r $keytmp
        _failure "Operation aborted."
    fi

    ${=WIPE} ${keytmp}/tomb.tmp # no need really, but anyway
    umount ${keytmp}
    rm -r ${keytmp}

    chown ${_uid}:${_gid} ${tombkey}

    _message "Done forging $tombkey"
    _success "Your key is ready:"
    ls -lh ${tombkey}
}

# Dig a tomb, means that 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 which improves the tomb's overall security
dig_tomb() {
    _message "Commanded to dig tomb $1"
    if [ "$1" = "" ]; then
        _warning "No tomb name specified for creation."
        return 1
    fi

    _check_swap

    tombfile=`basename $1`
    tombdir=`dirname $1`
    # make sure the file has a .tomb extension
    tombname=${tombfile%%\.*}
    tombfile=${tombname}.tomb

    # require the specification of the size of the tomb (-s) in MB
    tombsize="`option_value -s`"

    [ $tombsize ] || _failure "Size argument missing, use -s"

    [[ $tombsize != <-> ]] && _failure "Size argument is not an integer."

    [[ $tombsize -lt 10 ]] && _failure "Tombs can't be smaller than 10 megabytes."

    if [ -e ${tombdir}/${tombfile} ]; then
        _warning "A tomb exists already. I'm not digging here:"
        _warning " `ls -lh ${tombdir}/${tombfile}`"
        return 1
    fi

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

    _message "Generating ${tombfile} of ${tombsize}MiB"
    # we will first touch the file and set permissions: this way, even if interrupted, permissions are right
    touch ${tombdir}/${tombfile}
    chmod 0600 "${tombdir}/${tombfile}"
    chown $_uid:$_gid "${tombdir}/${tombfile}"

    _verbose "Data dump using ${DD[1]} from /dev/urandom"

    ${=DD} if=/dev/urandom bs=1048576 count=${tombsize} of=${tombdir}/${tombfile}

    if [ $? = 0 -a -e ${tombdir}/${tombfile} ]; then
        _message " `ls -lh ${tombdir}/${tombfile}`"
    else
        _failure "Error creating the tomb ${tombdir}/${tombfile}, operation aborted."
    fi

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


# this function locks a tomb with a key file
# in fact LUKS formatting the loopback volume
# it take arguments as the LUKS cipher to be used
lock_tomb_with_key() {
    if ! [ $1 ]; then
        _warning "No tomb specified for locking."
        _warning "Usage: tomb lock file.tomb file.tomb.key"
        return 1
    fi

    tombpath="$1"
    _message "Commanded to lock tomb ${tombfile}"

    tombdir=`dirname "$tombpath"`
    tombfile=`basename "$tombpath"`
    tombname="${tombfile%%\.*}"

    { test -f ${tombdir}/${tombfile} } || {
        _failure "There is no tomb here. You have to it dig first."
        return 1 }

    _verbose "Tomb found: ${tombdir}/${tombfile}"

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

    _verbose "Loop mounted on ${nstloop}"

    _message "Checking if the tomb is empty (we never step on somebody else's bones)."
    cryptsetup isLuks ${nstloop}
    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."
        losetup -d ${nstloop}
        _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 from options or file
    tombkey=`load_key`
    { test $? = 0 } || {
        losetup -d $nstloop
        _failure "Aborting operations: error loading key." }
        # make sure to call drop_key later

    # the encryption cipher for a tomb can be set when locking using -o
    if option_is_set -o; then
        cipher="`option_value -o`"
    else
        cipher="aes-xts-plain64:sha256"
        # old default was aes-cbc-essiv:sha256
        # for more alternatives refer to cryptsetup(8)
    fi
    _message "Locking using 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 = $tomb_pwd"
        ask_key_password "$tombkey" "$tomb_pwd" >-
    else
        ask_key_password "$tombkey" >-
    fi
    { test $? = 0 } || {
        losetup -d ${nstloop}
        _failure "No valid password supplied." }

    _success "Locking ${tombfile} with ${tombkey}"

    _message "Formatting Luks mapped device."
    print "$tomb_secret" | \
        cryptsetup --key-file -   --batch-mode \
        --cipher ${cipher} --key-size 256 --key-slot 0 \
        luksFormat ${nstloop}
    if ! [ $? = 0 ]; then
        _warning "cryptsetup luksFormat returned an error."
        losetup -d $nstloop
        _failure "Operation aborted."
    fi

    print "$tomb_secret" | \
        cryptsetup --key-file - \
        --cipher ${cipher} luksOpen ${nstloop} tomb.tmp
    if ! [ $? = 0 ]; then
        _warning "cryptsetup luksOpen returned an error."
        losetup -d $nstloop
        _failure "Operation aborted."
    fi

    # cleanup tombs
    drop_key # make sure all temp files are out

    _message "Formatting your Tomb with Ext3/Ext4 filesystem."
    ${=MKFS} ${tombname} /dev/mapper/tomb.tmp

    if [ $? != 0 ]; then
        _warning "Tomb format returned an error."
        _warning "Your tomb ${tombfile} may be corrupted."
    fi

    sync

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


    _message "Done locking $tombname using Luks dm-crypt ${create_cipher}"
    _success "Your tomb is ready in ${tombdir}/${tombfile} and secured with key ${tombkey}"

}

# This function changes the key that locks a tomb
change_tomb_key() {
    _message "Commanded to reset key for tomb $2"
    _check_swap

    newkey="`load_key`"
    { test $? = 0 } || {
        _failure "Aborting operations: error loading new key from -k" }

    oldkey="$1"
    { is_valid_key "$oldkey" } || {
        _failure "Old key invalid. 1st argument of setkey must be a valid key file." }

    { is_valid_tomb "$2" } || {
        _failure "Tomb invalid. 2nd argument of setkey must be a valid tomb file." }

    nstloop=`losetup -f`
    { test $? = 255 } && {
        _failure "Too many tombs are open. Please close any of them to proceed." }
    losetup -f "$2"
    cryptsetup isLuks ${nstloop}
    # is it a LUKS encrypted nest? we check one more timesee cryptsetup(1)
    { test $? = 0 } || {
        losetup -d "$nstloop"
        _failure "Not a valid LUKS encrypted volume: $2" }

    # we have everything, prepare to mount
    _success "Changing lock on tomb $tombname"
    _message "Old key: $oldkey"
    _message "New key: $newkey"

    # render the mapper
    mapdate=`date +%s`
    # save date of mount in minutes since 1970
    mapper="tomb.${tombname}.${mapdate}.`basename $nstloop`"

    if option_is_set --tomb-pwd; then
        tomb_new_pwd="`option_value --tomb-pwd`"
        _verbose "--tomb-pwd = $tomb_new_pwd"
        ask_key_password "$newkey" "$tomb_new_pwd" >-
    else
        ask_key_password "$newkey" >-
    fi
    { test $? = 0 } || {
        _failure "No valid password supplied for the new key." }
    newkeyfile="`safe_filename newkey`"
    print "$tomb_secret" > $newkeyfile


    # load the old key
    if option_is_set --tomb-old-pwd; then
        tomb_old_pwd="`option_value --tomb-old-pwd`"
        _verbose "--tomb-old-pwd = $tomb_old_pwd"
        ask_key_password "$oldkey" "$tomb_old_pwd" >-
    else
        ask_key_password "$oldkey" >-
    fi
    { test $? = 0 } || {
        _failure "No valid password supplied for the old key." }

    # luksOpen the tomb (not really mounting, just on the loopback)
    print "$tomb_secret" | \
        cryptsetup --key-file - luksOpen ${nstloop} ${mapper}
    { test $? = 0 } || {
        losetup -d "$nstloop"
        _failure "Unexpected error in luksOpen." }

    print "$tomb_secret"| \
        cryptsetup --key-file - luksChangeKey "$nstloop" "$newkeyfile"
    { test $? = 0 } || {
        losetup -d "$nstloop"
        _failure "Unexpected error in luksChangeKey." }

    ${=WIPE} "$newkeyfile"

    cryptsetup luksClose "${mapper}"
    { test $? = 0 } || {
        losetup -d "$nstloop"
        _failure "Unexpected error in luksClose." }

    drop_key
    losetup -d ${nstloop}

    _success "Succesfully changed key for tomb: $2"
    _message "The new key is: $newkey"

    return 0
}

# backward compatibility
create_tomb() {
    _verbose "create_tomb(): ${=@} ${=OLDARGS}"
    if ! [ $1 ]; then
        _warning "No tomb name specified for creation."
        return 1
    fi


    { test -r "$1" } && {
        _warning "Creating this tomb would overwrite an existing file. Operation aborted."
        _failure "`ls -lh $1`"    }

    { test $? = 0 } || { _failure "Failed to dig tomb, operation aborted." }


    tombfile=`basename $1`
    tombdir=`dirname $1`
    # make sure the file has a .tomb extension
    tombname=${tombfile%%\.*}
    tombfile=${tombname}.tomb

    ${TOMBEXEC} dig ${=PARAM}
    ${TOMBEXEC} forge ${tombdir}/${tombfile}.key
    { test $? = 0 } || { _failure "Failed to forge key, operation aborted." }

    ${TOMBEXEC} lock ${tombdir}/${tombfile} -k ${tombdir}/${tombfile}.key
    { test $? = 0 } || { _failure "Failed to lock tomb with key, operation aborted." }

    _success "Tomb $tombname succesfully created."
    ls -l ${tombfile}*
}

# }}} - Creation

# {{{ Open

# $1 = tombfile $2(optional) = mountpoint
mount_tomb() {
    _message "Commanded to open tomb $1"
    if [ "$1" = "" ]; then
        _warning "No tomb name specified for opening."
        return 1
    fi

    _check_swap

    # set up variables to be used
    # the full path is made with $tombdir/$tombfile

    local tombkey
    local tombfile
    local tombdir
    local tombname
    local tombpass
    tombfile=`basename ${1}`
    tombdir=`dirname ${1}`
    # check file type (if its a Luks fs)
    file ${tombdir}/${tombfile} | grep -i 'luks encrypted file' 2>&1 >-
    if [ $? != 0 ]; then
        _warning "$1 is not a valid tomb file, operation aborted."
        return 1
    fi
    tombname=${tombfile%%\.*}
    _verbose "Tomb found: ${tombdir}/${tombfile}"

    # load_key called here
    tombkey=`load_key`
    { test $? = 0 } || {
        _failure "Aborting operations: error loading key $tombkey"    }

    if [ "$2" = "" ]; then
        tombmount=/media/${tombfile}
        _message "Mountpoint not specified, using default: $tombmount"
    else
        tombmount=$2
    fi

    # check if its already open
    mount -l | grep "${tombfile}.*\[$tombname\]$" 2>&1 >-
    if [ $? = 0 ]; then
        _warning "$tombname is already open."
        _message "Here below its status is reported:"
        list_tombs ${tombname}
        return 0
    fi

    _success "Opening $tombfile on $tombmount"


    nstloop=`losetup -f`
    if [ $? = 255 ]; then
        _failure "Too many tombs open. Please close any of them to open another tomb."
    fi
    _verbose "Next free loop device: $nstloop"
    losetup -f ${tombdir}/${tombfile}

    cryptsetup isLuks ${nstloop}
    if [ $? != 0 ]; then
        # is it a LUKS encrypted nest? see cryptsetup(1)
        _warning "$tombfile is not a valid Luks encrypted storage file."
        losetup -d ${nstloop}
        return 1
    fi
    _message "This tomb is a valid LUKS encrypted device."

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

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

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

    mapper="tomb.${tombname}.${mapdate}.`basename $nstloop`"
    _verbose "dev mapper device: $mapper"
    _verbose "Tomb key: $tombkey"

    # take the name only, strip extensions
    keyname=${tombkey%%.*}
    _verbose "Tomb name: $keyname (to be engraved)"

    if option_is_set --tomb-pwd; then
        tomb_pwd="`option_value --tomb-pwd`"
        _verbose "--tomb-pwd = $tomb_pwd"
        ask_key_password "$tombkey" "$tomb_pwd" >-
    else
        ask_key_password "$tombkey" >-
    fi
    { test $? = 0 } || {
        losetup -d ${nstloop}
        _failure "No valid password supplied." }

    print -n "$tomb_secret" | \
        cryptsetup --key-file - luksOpen ${nstloop} ${mapper}

    # key dropped here
    drop_key

    if ! [ -r /dev/mapper/${mapper} ]; then
        losetup -d ${nstloop}
        _failure "Failure mounting the encrypted file."
    fi

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

    _message "Checking filesystem via $tombstat[3]"
    fsck -p -C0 /dev/mapper/${mapper}
    _verbose "Tomb engraved as $tombname"
    tune2fs -L ${tombname} /dev/mapper/${mapper} >-

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

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

    chown ${_uid}:${_gid} ${tombmount}
    chmod 0711 ${tombmount}

    _success "Success opening $tombfile on $fg_bold[white]$tombmount$fg_no_bold[white]"

    # print out when was opened the last time, by whom and where
    { test -r ${tombmount}/.last } && {
        tombtty="`cat ${tombmount}/.tty`"
        tombhost="`cat ${tombmount}/.host`"
        tombuid="`cat ${tombmount}/.uid`"
        tomblast="`cat ${tombmount}/.last`"
        tombuser=`awk -F: '/:'"$tombuid"':/ {print $1}' /etc/passwd`
        _message "Last visit by $fg_bold[white]$tombuser($tombuid)$fg_no_bold[white] from $fg_bold[white]$tombtty$fg_no_bold[white] on $fg_bold[white]$tombhost$fg_no_bold[white]"
        _message "on date $fg_bold[white]`date --date @${tomblast} +%c`$fg_no_bold[white]"
    }
    # write down the UID and TTY that opened the tomb
    rm -f ${tombmount}/.uid
    echo ${_uid} > ${tombmount}/.uid
    rm -f ${tombmount}/.tty
    echo ${_tty} > ${tombmount}/.tty
    # also the hostname
    rm -f ${tombmount}/.host
    echo `hostname` > ${tombmount}/.host
    # and the "last time opened" information
    # in minutes since 1970, this is printed at next open
    rm -f ${tombmount}/.last
    echo "`date +%s`" > ${tombmount}/.last
    # human readable: date --date=@"`cat .last`" +%c


    # process bind-hooks (mount -o bind of directories)
    # and post-hooks (execute on open)
    if ! option_is_set -n ; then
        exec_safe_bind_hooks ${tombmount}
        exec_safe_post_hooks ${tombmount} open
    fi
    return 0
}

# ## Hooks execution
exec_safe_bind_hooks() {
    if [[ -n ${(k)opts[-o]} ]]; then
        MOUNTOPTS=${opts[-o]}
    fi
    local MOUNTPOINT="${1}"
    local ME=${SUDO_USER:-$(whoami)}
    local HOME=$(awk -v a="$ME" -F ':' '{if ($1 == a) print $6}' /etc/passwd 2>-)
    if [ $? -ne 0 ]; then
        _warning "How pitiful!  A tomb, and no HOME."
        return 1
    fi
    if [ -z "$MOUNTPOINT" -o ! -d "$MOUNTPOINT" ]; then
        _warning "Cannot exec bind hooks without a mounted tomb."
        return 1
    fi
    if ! [ -r "$MOUNTPOINT/bind-hooks" ]; then
        _verbose "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 "${dir[1,2]}" = ".." ]; then
            _warning "bind-hooks map format: local/to/tomb local/to/\$HOME"
            continue
        fi
        if [ "${${maps[$dir]}[1]}" = "/" -o "${${maps[$dir]}[1,2]}" = ".." ]; then
            _warning "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
            _warning "bind-hook target not existent, skipping $HOME/${maps[$dir]}"
        elif [ ! -r "$MOUNTPOINT/$dir" ]; then
            _warning "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
}

# Post mount hooks
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
        _success "Post hooks found, executing as user $SUDO_USER."
        exec_as_user ${mnt}/post-hooks "$2" "$1"
    fi
}

# }}} - Tomb open

# {{{ List

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

    # list all open tombs
    mounted_tombs=(`list_tomb_mounts $1`)
    { test ${#mounted_tombs} = 0 } && {
        _failure "I can't see any ${1:-open} tomb, may they all rest in peace." }

    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%%%}
        tombsince=`date --date=@${mapper[(ws:.:)3]} +%c`

        # find out who opens it from where
        { test -r ${tombmount}/.tty } && {
            tombtty="`cat ${tombmount}/.tty`"
            tombhost="`cat ${tombmount}/.host`"
            tombuid="`cat ${tombmount}/.uid`"
            tombuser=`awk -F: '/:'"$tombuid"':/ {print $1}' /etc/passwd`
        }

    if option_is_set --get-mountpoint; then
        echo $tombmount
        continue
    fi
        # breaking up such strings is good for translation
        print -n "$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 "$fg_no_bold[white] open since "
        print "$fg_bold[white]$tombsince$fg_no_bold[white]"

        { test "$tombtty" = "" } || {
            print -n "$fg_no_bold[green]$tombname"
            print -n "$fg_no_bold[white] open by "
            print -n "$fg_bold[white]$tombuser"
            print -n "$fg_no_bold[white] from "
            print -n "$fg_bold[white]$tombtty"
            print -n "$fg_no_bold[white] on "
            print "$fg_bold[white]$tombhost"
        }

        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 [[ ${tombp} -ge 90 ]]; then
            print -n "$fg_no_bold[green]$tombname"
            print "$fg_bold[red] Your tomb is almost full!"
        fi

        # now check hooks
        mounted_hooks=(`list_tomb_binds $tombname`)
        for h in ${mounted_hooks}; do
            print -n "$fg_no_bold[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
}


# 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() {
    if [ "$1" = "" ]; then
        # list all open tombs
        mount -l \
            | awk '
BEGIN { main="" }
/^\/dev\/mapper\/tomb/ {
  if(main==$1) next;
  print $1 ";" $3 ";" $5 ";" $6 ";" $7
  main=$1
}
'
    else
        # list a specific tomb
        mount -l \
                | awk -vtomb="[$1]" '
BEGIN { main="" }
/^\/dev\/mapper\/tomb/ {
  if($7!=tomb) next;
  if(main==$1) next;
  print $1 ";" $3 ";" $5 ";" $6 ";" $7
  main=$1
}
'
    fi
}

# list_tomb_binds
# print out an array of mounted bind hooks (internal use)
# format is semi-colon separated list of attributes
# needs an argument: name of tomb whose hooks belong
list_tomb_binds() {
    if [ "$1" = "" ]; then
        _failure "Internal error: list_tomb_binds called without argument."; fi

    # list bind hooks on util-linux 2.20 (Debian 7)
    mount -l \
        | awk -vtomb="$1" '
BEGIN { main="" }
/^\/dev\/mapper\/tomb/ {
  if($7!=tomb) next;
  if(main=="") { main=$1; next; }
  if(main==$1)
    print $1 ";" $3 ";" $5 ";" $6 ";" $7
}
'

    # list bind hooks on util-linux 2.17 (Debian 6)
    tombmount=`mount -l \
      | awk -vtomb="$1" '
/^\/dev\/mapper\/tomb/ { if($7!=tomb) next; print $3; exit; }'`

    mount -l | grep "^$tombmount" \
        | awk -vtomb="$1" '
        /bind/ { print $1 ";" $3 ";" $5 ";" $6 ";" $7 }'
}

# }}} - Tomb list

# {{{ Index and search

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

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

    _verbose "$updatedbver"

    mounted_tombs=(`list_tomb_mounts $1`)
    { test ${#mounted_tombs} = 0 } && {
        if [ $1 ]; then _failure "There seems to be no open tomb engraved as [$1]"
        else _failure "I can't see any open tomb, may they all rest in peace."
        fi
    }


    _success "Creating and updating search indexes."

    # start the LibreOffice document converter if installed
    { command -v unoconv >- } && {
        unoconv -l 2>- &
        _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]}
        { test -r ${tombmount}/.noindex } && {
            _message "Skipping $tombname (.noindex found)."
            continue }
        _message "Indexing $tombname filenames..."
        updatedb -l 0 -o ${tombmount}/.updatedb -U ${tombmount}

        # here we use swish to index file contents
        { test $SWISH = 1 } && {
            _message "Indexing $tombname contents..."
            swishrc=`safe_filename swish`

            cat <<EOF > $swishrc
# index directives
DefaultContents TXT*
IndexDir $tombmount
IndexFile $tombmount/.swish
# exclude images
FileRules filename regex /\.jp.?g/i
FileRules filename regex /\.png/i
FileRules filename regex /\.gif/i
FileRules filename regex /\.tiff/i
FileRules filename regex /\.svg/i
FileRules filename regex /\.xcf/i
FileRules filename regex /\.eps/i
FileRules filename regex /\.ttf/i
# exclude audio
FileRules filename regex /\.mp3/i
FileRules filename regex /\.ogg/i
FileRules filename regex /\.wav/i
FileRules filename regex /\.mod/i
FileRules filename regex /\.xm/i
# exclude video
FileRules filename regex /\.mp4/i
FileRules filename regex /\.avi/i
FileRules filename regex /\.ogv/i
FileRules filename regex /\.ogm/i
FileRules filename regex /\.mkv/i
FileRules filename regex /\.mov/i
# exclude system
FileRules filename is ok
FileRules filename is lock
FileRules filename is control
FileRules filename is status
FileRules filename is proc
FileRules filename is sys
FileRules filename is supervise
FileRules filename regex /\.asc$/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

            _verbose "Using swish-e to create index."
            swish-e -c $swishrc -S fs -v3
            rm -f $swishrc
        }

        _message "Search index updated."
    done
}
search_tombs() {
    { command -v locate >- } || {
        _failure "Cannot index tombs on this system: updatedb (mlocate) not installed." }

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

    _verbose "$updatedbver"

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

    _success "Searching for: $fg_bold[white]${(f)@}$fg_no_bold[white]"
    for t in ${mounted_tombs}; do
        _verbose "Checking for index: ${t}"
        mapper=`basename ${t[(ws:;:)1]}`
        tombname=${t[(ws:;:)5]}
        tombmount=${t[(ws:;:)2]}
        if [ -r ${tombmount}/.updatedb ]; then

        # use mlocate to search hits on filenames
        _message "Searching filenames in tomb $tombname"
        locate -d ${tombmount}/.updatedb -e -i "${(f)@}"
        _message "Matches found: `locate -d ${tombmount}/.updatedb -e -i -c ${(f)@}`"

        # use swish-e to search over contents
        { test $SWISH = 1 } && { test -r $tombmount/.swish } && {
            _message "Searching contents in tomb $tombname"
            swish-search -w ${=@} -f $tombmount/.swish -H0 }

        else
            _warning "Skipping tomb $tombname: not indexed."
            _warning "Run 'tomb index' to create indexes."
        fi
    done
    _message "Search completed."
}

# }}} - Index and search

# {{{ Resize

# resize tomb file size
resize_tomb() {
    _message "Commanded to resize tomb $1 to $opts[-s] megabytes."
    if ! [ $1 ]; then
        _failure "No tomb name specified for resizing."
    elif ! [ -r "$1" ]; then
        _failure "Cannot find $1"
    fi
    # $1 is the tomb file path

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

    local c tombpass tombkey

    tombdir=`dirname $1`
    tombfile=`basename $1`
    tombname=${tombfile%%\.*}

    # load key from options or file
    local tombkey="`load_key`"
    # make sure to call drop_key later
    { test -r "$tombkey" } || {
        _failure "Aborting operations: key not found, use -k" }

    local oldtombsize=$(( `stat -c %s "$1" 2>-` / 1048576 ))
    local mounted_tomb=`mount -l |
        awk -vtomb="[$tombname]" '/^\/dev\/mapper\/tomb/ { if($7==tomb) print $1 }'`

    if [ "$mounted_tomb" ]; then
        _failure "The tomb $tombname is open, to resize it it needs to be closed."
    fi

    if ! [ "$newtombsize" ] ; then
        _failure "You must specify the new size of $tombname"
    elif [[ $newtombsize != <-> ]]; then
        _failure "Size is not an integer."
    elif [ "$newtombsize" -le "$oldtombsize" ]; then
        _failure "The new size must be greater then old tomb size."
    fi

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

    act "Generating ${tombfile} of ${newtombsize}MiB"

    _verbose "Data dump using ${DD[1]} from /dev/urandom"
    ${=DD} if=/dev/urandom bs=1048576 count=${delta} >> ${tombdir}/${tombfile}

    { test $? = 0 } || {
        _failure "Error creating the extra resize $tmp_resize, operation aborted." }

    if option_is_set --tomb-pwd; then
        tomb_pwd="`option_value --tomb-pwd`"
        _verbose "--tomb-pwd = $tomb_pwd"
        ask_key_password "$tombkey" "$tomb_pwd" >-
    else
        ask_key_password "$tombkey" >-
    fi
    { test $? = 0 } || {
        _failure "No valid password supplied." }

    local nstloop=`losetup -f`
    if [ $? = 255 ]; then
        _failure "Too many tombs opened. Please close any of them to open another tomb."
    fi

    losetup -f ${tombdir}/${tombfile}

    local mapdate=`date +%s`
    local mapper="tomb.${tombname}.${mapdate}.`basename $nstloop`"

    print "$tomb_secret" | \
        cryptsetup --key-file - luksOpen ${nstloop} ${mapper}

    drop_key # cleanup after load_key

    if ! [ -r /dev/mapper/${mapper} ]; then
        losetup -d ${nstloop}
        _failure "Failure mounting the encrypted file."
    fi

    cryptsetup resize "${mapper}"
    if [ $? != 0 ]; then
        losetup -d ${nstloop}
        _failure "cryptsetup failed to resize $mapper"
    fi

    e2fsck -p -f /dev/mapper/${mapper}
    if [ $? != 0 ]; then
        losetup -d ${nstloop}
        _failure "e2fsck failed to check $mapper"
    fi

    resize2fs /dev/mapper/${mapper}
    if [ $? != 0 ]; then
        losetup -d ${nstloop}
        _failure "resize2fs failed to resize $mapper"
    fi

    sleep 1 # needs to settle a bit

    # close and free the loop device
    cryptsetup luksClose "${mapper}"
    losetup -d ${nstloop}

    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

    { test ${#mounted_tombs} = 0 } && {
            _warning "There is no open tomb to be closed."
            return 1 }

    { test ${#mounted_tombs} -gt 1 } && { test "$1" = "" } && {
            _warning "Too many tombs mounted, please specify one (see tomb list)"
            _warning "or issue the command 'tomb close all' to close them all."
            return 1 }

    _message "Tomb close $1"

    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]}

        _verbose "Name: $tombname"
        _verbose "Mount: $tombmount"
        _verbose "Mapper: $mapper"

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

        if [ $SLAM ]; then
            _success "Slamming tomb $tombname mounted on $tombmount"
            _message "Kill all processes busy inside the tomb."
            if ! slam_tomb "$tombmount"; then
                _warning "Cannot slam the tomb $tombname"
                return 1
            fi
        else
            _message "Closing tomb $tombname mounted on $tombmount"
        fi

    # check if there are binded dirs and close them
        bind_tombs=(`list_tomb_binds $tombname`)
        for b in ${bind_tombs}; do
            bind_mapper="${b[(ws:;:)1]}"
            bind_mount="${b[(ws:;:)2]}"
            _message "Closing tomb bind hook: $bind_mount"
            umount $bind_mount
            if [[ $? != 0 ]]; then
                if [ $SLAM ]; then
                    _success "Slamming tomb: killing all processes using this hook."
                    slam_tomb "$bind_mount"
                    if [[ $? == 1 ]]; then
                        _warning "Cannot slam the bind hook $bind_mount"
                        return 1
                    fi
                    umount $bind_mount
                else
                    _warning "Tomb bind hook $bind_mount is busy, cannot close tomb."
                fi
            fi
        done

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

        _verbose "Performing umount of $tombmount"
        umount ${tombmount}
        if ! [ $? = 0 ]; then _warning "Tomb is busy, cannot umount!"
        else
        # this means we used a "default" mount point
            { test "${tombmount}" = "/media/${tombname}.tomb" } && {
                rmdir ${tombmount} }
        fi

        cryptsetup luksClose $mapper
        { test $? = 0 } || {
            _warning "Error occurred in cryptsetup luksClose ${mapper}"
            return 1 }

        losetup -d "/dev/$tombloop"

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

    done # loop across mounted tombs

    return 0
}

# Kill all processes using the tomb
slam_tomb() {
    # $1 = tomb mount point
    if [[ -z `fuser -m "$1" 2>-` ]]; then
        return 0
    fi
    #Note: shells are NOT killed by INT or TERM, but they are killed by HUP
    for s in TERM HUP KILL; do
        _verbose "Sending $s to processes inside the tomb:"
        if option_is_set -D; then
            ps -fp `fuser -m /media/a.tomb 2>-`|
            while read line; do
                _verbose $line
            done
        fi
        fuser -s -m "$1" -k -M -$s
        if [[ -z `fuser -m "$1" 2>-` ]]; then
            return 0
        fi
        if ! option_is_set -f; then
            sleep 3
        fi
    done
    return 1
}

# }}} - Tomb close

# {{{ Main routine
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 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")
    #
    #    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 U: -uid=U G: -gid=G T: -tty=T -no-color -unsecure-dev-mode)
    subcommands_opts[__default]=""
    subcommands_opts[open]="f -force n -nohook=n k: -key=k -kdf: o: -ignore-swap -sudo-pwd: -tomb-pwd: "
    subcommands_opts[mount]=${subcommands_opts[open]}

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

    subcommands_opts[forge]="f -force -ignore-swap k: -key=k -kdf: o: -tomb-pwd: -use-urandom "
    subcommands_opts[dig]="f -force -ignore-swap s: -size=s "
    subcommands_opts[lock]="f -force -ignore-swap k: -key=k -kdf: o: -sudo-pwd: -tomb-pwd: "
    subcommands_opts[setkey]="k: -key=k f -force -ignore-swap -kdf: -sudo-pwd: -tomb-old-pwd: -tomb-pwd: "
    subcommands_opts[engrave]="k: -key=k "

    subcommands_opts[passwd]="k: -key=k f -force -ignore-swap -kdf: -tomb-old-pwd: -tomb-pwd: "
    subcommands_opts[close]="-sudo-pwd: "
    subcommands_opts[help]=""
    subcommands_opts[slam]=""
    subcommands_opts[list]="-get-mountpoint "

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

    subcommands_opts[help]=""
    subcommands_opts[bury]="f -force k: -key=k -tomb-pwd: "
    subcommands_opts[exhume]="f -force k: -key=k -tomb-pwd: "
    # subcommands_opts[decompose]=""
    # subcommands_opts[recompose]=""
    # subcommands_opts[install]=""
    subcommands_opts[askpass]=""
    subcommands_opts[mktemp]=""
    subcommands_opts[source]=""
    subcommands_opts[resize]="f -force -ignore-swap s: -size=s k: -key=k -tomb-pwd: "
    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 --optiion-parsing
    zparseopts -M -D -Adiscardme ${every_opts}
        if [[ -n ${(k)discardme[--option-parsing]} ]]; then
                echo $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 \"$subcommand\"."
        _failure "Please try -h for help." 127
#        _failure "Subcommand '$subcommand' doesn't exist" 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 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."
            _failure "See \"tomb help\" for more info." 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
                _failure "Unrecognized option $arg for subcommand $subcommand" 127
            fi
        fi
        PARAM+=$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
    if ! option_is_set --no-color; then
        autoload colors; colors
    fi
    if ! option_is_set --unsecure-dev-mode; then
        for opt in --sudo-pwd --tomb-pwd --use-urandom --tomb-old-pwd; do
            if option_is_set $opt; then
                _failure "You specified option $opt, which is DANGEROUS and should only be used for testing\nIf you really want so, add --unsecure-dev-mode" 127
            fi
        done
    fi

    # when we run as root, we remember the original uid:gid
    # to set permissions for the calling user and drop privileges
    if option_is_set -U; then _uid="`option_value -U`"; fi
    if option_is_set -G; then _gid="`option_value -G`"; fi
    if option_is_set -T; then _tty="`option_value -T`"; fi

    _verbose "Tomb command: $subcommand ${PARAM}"
    _verbose "Caller: uid[$_uid], gid[$_gid], tty[$_tty]."

    case "$subcommand" in

        # new creation in three steps
        forge)
            check_priv
            forge_key ${=PARAM}
            ;;
        dig)
            dig_tomb ${=PARAM}
            ;;
        lock)
            check_priv
            lock_tomb_with_key ${=PARAM}
            ;;

        setkey)
            check_priv
            change_tomb_key ${=PARAM}
            ;;

        engrave)
            { test "$QRENCODE" = 0 } && {
                _failure "QREncode not installed: cannot engrave keys on paper." }
            engrave_key ${=PARAM}
            ;;

        # backward compat
        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)."
            ;;

        mount|open)
            check_priv
            mount_tomb $PARAM[1] $PARAM[2]
            ;;
        umount|close|slam)
            check_priv
            [ "$subcommand" =  "slam" ] && SLAM=1
            umount_tomb $PARAM[1]
            ;;
        passwd)
            change_passwd $PARAM[1]
            ;;
        list)
            list_tombs $PARAM[1]
            ;;

        index)
            index_tombs $PARAM[1]
            ;;
        search)
            search_tombs ${=PARAM}
            ;;

        help)
            usage
            ;;
        bury)
            { test "$STEGHIDE" = 0 } && {
                _failure "Steghide not installed: cannot bury keys into images." }
            bury_key $PARAM[1]
            ;;
        exhume)
            { test "$STEGHIDE" = 0 } && {
                _failure "Steghide not installed: cannot exhume keys from images." }
            exhume_key $PARAM[1]
            ;;
        resize)
            { test "$RESIZER" = 0 } && {
                _failure "Resize2fs not installed: cannot resize tombs." }
            check_priv
            resize_tomb $PARAM[1]
            ;;

        # internal commands useful to developers
        'source')   return 0 ;;
        askpass)    ask_password $PARAM[1] $PARAM[2] ;;
        mktemp)     safe_dir $PARAM[1] ;;

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

 Copyright (C) 2007-2014 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>
EOF
            option_is_set -v && {
                cat <<EOF
 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.

System utils:

 `sudo -V | head -n1`
 `cryptsetup --version`
 `pinentry --version`
 `gpg --version | head -n1` - key forging algorithms (GnuPG symmetric ciphers):
`list_gnupg_ciphers`
EOF
                return 0
            }
            usage
            ;;
        *)
            _warning "Command \"$subcommand\" not recognized."
            _message "Try -h for help."
            return 1
            ;;
    esac
    return $?
}

# }}}

# {{{ Run
check_bin


main $@
ret=$?
if [[ $ret != 0 ]]; then #this "if" seems useless, but avoid source tomb source from exiting
    exit $ret
fi
# }}}

# -*- tab-width: 4; indent-tabs-mode:nil; -*-
# vim: set shiftwidth=4 expandtab: