Prototype linux directory locker

dLocker.sh

#!/bin/bash

# dLocker.sh by Brian Wilson
#
# Quick and dirty prototype for a directory locker
#
# Initialization Example:
# $ cd dLocker
# $ ls
# dLocker/ dLocker.sh
# $ ./dLocker.sh --init
#
# This will compress ./dLocker/dLocker into a gzipped tarball
# and encrypt it with gpg2 as ./dLocker.lk
# From here usage of the script is fairly straight forward.
# Simply use ./dLocker.sh -u to unlock the archive. 
#
# NOTE: Any changes made to the unlocked directory are stored in /tmp/dLocker,
# so if the system were to go down before the directory is locked again, all data
# would be lost.
#
# REPEAT: The only way to save data at this moment, is to relock the directory!

BASE=$(basename $PWD)
TMPDIR="/tmp/$BASE"
# Name for GPG key in keyring
USER="Brian Wilson"

# Lock the files up
lock() {
    if [ -d "$TMPDIR" ]; then
        echo "[OK] $TMPDIR exists"
        echo "Archiving data..."
        if tar -C /tmp -czf $TMPDIR.tar.gz $BASE; then
            echo "[OK] Archiving successful"
            echo "Encrypting for user: $USER..."
            if gpg2 -o $BASE.lk -se -r "$USER" $TMPDIR.tar.gz; then
                echo "[OK] Encryption successful"
                echo "Cleaning up..."
                #TODO: Find a better way to remove files. Recursively zero them maybe
                rm -rf $TMPDIR
                rm $TMPDIR.tar.gz
                # $ rm -rf $BASE is used when the --init argument is used
                unlink $BASE 2> /dev/null || rm -rf $BASE
            else
                echo "[ERROR] Encryption failed!"
                exit -1
            fi 
        fi    
    else
        echo "[ERROR] Data has not been initialized yet..."
        echo "[ERROR] Please use $0 --init"
        exit -1
    fi
}

unlock() {
    if [ -f $BASE.lk ]; then
        if gpg2 -d $BASE.lk > $TMPDIR.tar.gz; then
            echo "[OK] Decryption successful"
            echo "Extracting archive..."
            if tar -C /tmp -xzf $TMPDIR.tar.gz; then
                echo "[OK] Extraction successful"
                echo "Soft linking to current directory..."
                ln -s $TMPDIR $PWD/$BASE
                echo "[OK] Done!"
            else
                echo "[ERROR] Extraction failed!"
            fi
        else
            echo "[ERROR] Decryption failed!"
        fi
    else
        echo "[ERROR] Could not find $PWD/$BASE.lk!"
    fi
}

init() {
    if [ -d $BASE ]; then
        cp -R $BASE $TMPDIR
        if lock; then
            echo "[OK] Initialization complete"
            echo "Use $0 --unlock to use your files"
            # ./$BASE still needs to be zeroed
        fi
    fi
}

showHelp() {
    echo "Welcome to $0! Here are the available commands:"
    printf "\t--init, -i\tInitialize a new locked directory\n"
    printf "\t--lock, -l\tLock an existing unlocked directory\n"
    printf "\t--unlock, -u\tUnlock an existing locked directory\n"
}

case "$1" in
    --init | -i)
        init ;;
    --lock | -l)
        lock ;;
    --unlock | -u)
        unlock ;;
    *)
        showHelp ;;

esac