#!/bin/bash
###########################################################################
############### A quick way to securely erase a list of files
###########################################################################

ww="which wipe >/dev/null"
eval $ww
if [ "$?" != "0" ]; then echo "!! You need to install wipe to use this tool !!"; unset ww; exit 1; fi
####
declare -i ctstat #files deleted
declare -i ctfail #files failed
declare -i ctignore #files ignored (already removed)
cfd=""
cff=""
cfi=""
ctstat=0
ctfail=0
ctignore=0
laststat=""
devseed="/dev/random"
tmprnd="./.rmprnd"
_retval=""
wforce=""
wrecurse=""
wkeep=""
wcomopts="-Sr -R $devseed -Ma -Q3 -iq$wforce$wrecurse$wkeep"
wcom="wipe $wcomopts"
bvb="n"
###
# this is the only way to get aliasing to work
shopt -s expand_aliases
alias echo='echo -e' #gets removed in quit
#####
#functions
usage() {
    echo "usage: $0 [options] <file1 [\"file2\" \'file3\' ...]>"
    echo "usage: $0 -h|--help\t\tshow this"
    echo "usage: $0 -f|--force\t\tforce wipe, do not prompt"
    echo "usage: $0 -r|--recurse\t\tallow the removal of the entire directory tree"
    echo "usage: $0 -k\t\tdo not delete the file after wiping it"
    echo "usage: $0 quickwipe may encounter problems with gathering random data (\"low entropy\")\n\t\t\tif this happens, the program will try to gather random data from 3 other sources before giving up\n\t\t\tdata sources (in order): /dev/random, /dev/urandom/, 'openssl rand' output"
    quit 0
}
quit() {
    unalias echo
    shopt -u expand_aliases
    unset devseed
    rm -f $tmprnd
    unset tmprnd
    unset _retval
    unset wforce
    unset wrecurse
    unset wcom
    unset wcomopts
    unset wkeep
    unset gencrstemp
    unset arg1
    unset arg2
    unset shorti
    unset ctstat
    unset ctfail
    unset ctignore
    unset laststat
    unset cfd
    unset cff
    unset cfi
    unset bvb
    unset ww
    echo "(exitting with code $1)"
    exit $1
}
_reseed() {
    #devseed must be updated prior to calling this function

    orand="openssl rand -out $devseed 10000000" #10mb of random data
    eval $orand
    return $?
}
execwipe() {
    #devseed must be updated prior to calling this function

    wcomopts="-Sr -R $devseed -Ma -Q3 -iq$wforce$wrecurse$wkeep"
    wcom="wipe $wcomopts $1 2>/dev/null"
    eval $wcom
    return $?
}
genshorti() {
    shorti=""
    arg1="$1"
    arg1=${#arg1}
    if [ "$arg1" -gt "7" ]; then shorti="${i:0:7}..."; else shorti="$i"; fi
}
_ks() {
    #cfd files del
    #cff file fail
    #cfi file ignore

    _arg1="$1"

    # file was forced/failed
    if [ "$#" == "2" ]; then _arg2="$2"
    else _arg2=""; fi
    if [ "$_arg2" == "f" ]; then cff="$cff $_arg1"; ((ctfail++)); return 0; fi

    # check file existence
    if [ ! -f "$_arg1" ]; then cfd="$cfd $_arg1"; ((ctstat++)); return 0
    else cff="$cff $_arg1"; ((ctfail++)); fi
}
keepstat() {
    #gather some stats (only works if --keep is NOT enabled)
    if [ "$wkeep" == "k" ]; then return 0; fi

    arg1="$1"

    # get 2nd var
    if [ "$#" == "2" ]; then arg2="$2"
    else arg2=""; fi

    # file was ignored (i = ignore flag)
    if [ "$arg2" == "i" ]; then cfi="$cfi $arg1"; ((ctignore++)); laststat="$arg1"; return 0; fi

    # duplicate call
    if [ "$laststat" == "$arg1" ]; then

        # only run _ks if the force flag it given
        if [ "$arg2" == "f" ]; then
            _ks "$arg1" "f"
            laststat="$arg1"
        fi
    else
        _ks "$arg1"
        laststat="$arg1"
        #echo "ls $laststat || curr $arg1"
    fi
}

# https://gist.github.com/cosimo/3760587
OPTS=`getopt -o hfrkv --long help,force,recurse,keep,verbose -n 'parse-options' -- "$@"`
if [ $? != 0 ]; then echo "Failed parsing options..."; quit 1; fi
eval set -- "$OPTS"

# parse options
while true; do
        case "$1" in
                ( -h | --help )
                        usage
                        ;;
        ( -f | --force )
            wforce="f"
            ;;
        ( -r | --recurse )
            wrecurse="r"
            ;;
        ( -k | --keep )
            wkeep="k"
            ;;
        ( -v | --verbose )
            bvb="y"
            ;;
        ( -- ) shift; break ;;
        ( -* ) echo "$0: error - unrecognized option $1" 1>&2; quit 1;;
        ( * ) break ;;
    esac
    shift
done

# if there are no more arguments, show usage and quit
if [ "$#" -lt "1" ]; then usage; quit 1; fi


# parse files
for i in "$@"; do
    # check existence of file
    if [ ! -f "$i" ]; then echo "wipe: file not found"; keepstat "$i" "i"; shift; continue; fi

    # try wipe with /dev/random
    devseed="/dev/random"; genshorti $i
    echo -n "trying quickwipe($devseed) on \"$shorti\" -->  "
    execwipe $i

        # WIPEFAIL on /dev/random
        if [ "$?" != "0" ]; then echo "failed!"
        else keepstat "$i"; shift; continue; fi

    # try wipe with /dev/urandom
    devseed="/dev/urandom"; genshorti $i
    echo -n "\ttrying quickwipe($devseed) on \"$shorti\" -->  "
    execwipe $i

        # WIPEFAIL on /dev/urandom
        if [ "$?" != "0" ]; then echo "failed!"
        else keepstat "$i"; shift; continue; fi

    # try wiping with $tmprnd
    devseed="$tmprnd"
    echo -n "\ttrying to seed $devseed... "
    _reseed

        # SEEDFAIL on $tmprnd
        if [ "$?" != "0" ]; then echo "failed!"
        else
            genshorti $i
            echo -n "\ttrying quickwipe($devseed) on \"$shorti\" -->  "
            # seeding $tmprnd succeeded, try wiping
            devseed="$tmprnd"
            execwipe $i
            _retval="$?"
        fi

        # WIPEFAIL on $tmprnd
        if [ "$_retval" != "0" ]; then echo "failed!"
        else keepstat "$i"; shift; continue; fi

    # try seeding /dev/random
    devseed="/dev/random"
    echo -n "\ttrying to seed $devseed... "
    _reseed

        # SEEDFAIL on /dev/random
        if [ "$?" != "0" ]; then echo "failed!"
        else
            genshorti $i
            echo -n "\ttrying quickwipe($devseed) on \"$shorti\" -->  "
            #seeding /dev/random succeeded, try wipping
            devseed="/dev/random"
            execwipe $i
            _retval="$?"
        fi
            # WIPEFAIL on /dev/random
            if [ "$_retval" != "0" ]; then echo "failed!"
            else keepstat "$i"; shift; continue; fi

    # try seeding /dev/urandom
    devseed="/dev/urandom"
    echo -n "\ttrying to seed $devseed... "
    _reseed

        # final stop ... if wipe fails, shift & continue
        # SEEDFAIL on /dev/urandom
        if [ "$?" != "0" ]; then genshorti $i; echo "failed!\n!!\tout of options! quickwipe on \"$shorti...\" FAILED"; keepstat "$i" "f"; shift; continue
        else
            genshorti $i
            echo -n "trying quickwipe($devseed) on \"$shorti\" -->  "
            #seeding /dev/urandom succeeded, try wipping
            devseed="/dev/urandom"
            execwipe $i
            _retval="$?"
        fi
            # WIPEFAIL on /dev/urandom
            if [ "$_retval" != "0" ]; then genshorti $i; echo "failed!\n!!\tout of options! quickwipe on \"$shorti...\" FAILED"; keepstat "$i" "f"; shift; continue
            else keepstat "$i"; shift; continue; fi

    # move to next argument
    shift
done

if [ "$wkeep" == "" ]; then echo "\nfinished:\n$ctstat files wiped\n$ctfail files failed to be wiped\n$ctignore files ignored"; fi
if [ "$bvb" == "y" ]; then echo "\nfiles wiped: $cfd\nfiles ignored: $cfi\nfiles failed: $cff"; fi