#!/bin/sh

# Why not use "openct-tool rwait" instead of polling opensc-tool exit status?
# Well openct daemon has to be running which interferes with pcscd since both
# implement reader drivers, my particular CCID reader (SCM SCR331-LC1) doesn't
# work with the CCID driver in openct, however it does work with pcscd.

# Why not use "opensc-tool --wait" instead of polling opensc-tool exit status?
# Although opensc-tool --help reports that there is a --wait option, it doesn't
# seem to be implemented.

# Load configuration and test set default value if missing
. /etc/default/decrypt_pkcs
SMARTCARD_PRESENCE_COMMAND=${SMARTCARD_PRESENCE_COMMAND:-/usr/bin/opensc-tool}
SMARTCARD_PRESENCE_ARGS=${SMARTCARD_PRESENCE_ARGS:-'-n'}
DECIPHER_COMMAND=${DECIPHER_COMMAND:-/usr/bin/pkcs15-crypt}
DECIPHER_ARGS=${DECIPHER_ARGS:-'--decipher --pkcs1 --raw --input'}
DECIPHER_ASK_PIN=${DECIPHER_ASK_PIN:-'--pin'}
DECIPHER_MULTI=${DECIPHER_MULTI:-0}
KEY="${1}" 

check_plymouth() {
    plymouth=0
    if [ -x /bin/plymouth ] && plymouth --ping > /dev/null ; then
        plymouth=1
    fi
}

check_osk_sdl() {
    osk_sdl=0
    if [ -f /usr/bin/osk-sdl ] ; then
        osk_sdl=1
        export ETNA_MESA_DEBUG=no_supertile
        export SDL_VIDEODRIVER=kmsdrm
    fi
}

check_card() {
    cardfound=0
    if $SMARTCARD_PRESENCE_COMMAND $SMARTCARD_PRESENCE_ARGS >/dev/null 2>&1; then
        cardfound=1
    fi
}

check_key() {
    if [ $DECIPHER_MULTI = 1 ] ; then
        temp=$($DECIPHER_MULTI_SCRIPT)
        KEY=$(echo $temp | awk '{print $1}')
        DECIPHER_EXTRA_ARGS=$(echo $temp | awk '{$1=""; print}')
    fi
}

log_message() {
    if [ $plymouth = 1 ] ; then
        plymouth display-message --text="$@" 2>/dev/null
    else
        echo "$@" >&2
    fi 
}

fallback() {
    log_message 'Asking for passphrase'
    if [ $plymouth = 1 ] ; then
        if [ $osk_sdl = 1 ] ; then
            plymouth hide-splash 2>/dev/null
		    /usr/bin/osk-sdl -k -d "${CRYPTTAB_SOURCE}" -n "${CRYPTTAB_NAME}" -c /etc/osk.conf 2> /dev/null \
              || panic "Failure running osk-sdl. Good luck."
            plymouth show-splash 2>/dev/null
        else
            plymouth ask-for-password --prompt "Try LUKS password for $CRYPTTAB_NAME: " 2>/dev/null
            exit 0
	fi
    else
        if [ $osk_sdl = 1 ] ; then
		    /usr/bin/osk-sdl -k -d "${CRYPTTAB_SOURCE}" -n "${CRYPTTAB_NAME}" -c /etc/osk.conf 2> /dev/null \
              || panic "Failure running osk-sdl. Good luck."
        else
            echo </dev/console 2>/dev/console
            exit 0
	fi
        	
    fi
    exit $?
}

wait_card() {
    check_card
    if [ $cardfound = 0 ] ; then
        log_message "Waiting for Smart Card..."
        tries=0
        while [ $cardfound = 0 ] && [ $tries -lt 15 ] ; do
            sleep 1
            check_card
            tries=$(($tries + 1))
        done
        if [ $cardfound = 0 ] ; then
            log_message 'Failed to find Smart Card card!'
	    if [ -b "/dev/mapper/${CRYPTTAB_NAME}" ] ; then 
		log_message 'Already decrypted'
		exit 0
	    else
		fallback
	    fi
        fi
    fi
}


check_plymouth
check_osk_sdl

if [ -b "/dev/mapper/${CRYPTTAB_NAME}" ] ; then 
    log_message 'Already decrypted'
    exit 0
fi

wait_card
check_key

if [ $plymouth = 1 ] ; then
    if [ $osk_sdl = 1 ] ; then
	# Get pin number from osk_sdl
	plymouth hide-splash 2>/dev/null
	${DECIPHER_COMMAND} $DECIPHER_ARGS "$KEY" $DECIPHER_EXTRA_ARGS \
		$DECIPHER_ASK_PIN "$(/usr/bin/osk-sdl -k -d "${CRYPTTAB_SOURCE}" -n "${CRYPTTAB_NAME}" -c /etc/osk.conf 2> /dev/null | tail -n1)"
	plymouth show-splash 2>/dev/null
    else
	# Get pin number from plymouth
	${DECIPHER_COMMAND} $DECIPHER_ARGS "$KEY" $DECIPHER_EXTRA_ARGS \
                $DECIPHER_ASK_PIN "$(plymouth ask-for-password --prompt "Enter pin for $CRYPTTAB_NAME ($KEY): ")"
    fi
else
    if [ $osk_sdl = 1 ] ; then
	# Get pin number from osk_sdl
	${DECIPHER_COMMAND} $DECIPHER_ARGS "$KEY" $DECIPHER_EXTRA_ARGS \
		$DECIPHER_ASK_PIN "$(/usr/bin/osk-sdl -k -d "${CRYPTTAB_SOURCE}" -n "${CRYPTTAB_NAME}" -c /etc/osk.conf 2> /dev/null | tail -n1)"
    else
	# Get pin number from console
	${DECIPHER_COMMAND} $DECIPHER_ARGS "$KEY" $DECIPHER_EXTRA_ARGS </dev/console 2>/dev/console
    fi
fi

exit $?