#! /bin/sh
# #############################################################################

       NAME_="obfsh"
       HTML_="shell script obfuscator"
    PURPOSE_="shell script obfuscator"
   SYNOPSIS_="$NAME_ [-cd <n>] [-ej <n1>-<n2>] [-g <n1>-<n2>+<n3>-<n4>] [-vhmli] -f <file> [file...]"
   REQUIRES_="standard GNU commands"
    VERSION_="1.2"
       DATE_="2001-10-12; last update: 2004-08-09"
     AUTHOR_="Dawid Michalczyk <dm@eonworks.com>"
        URL_="www.comp.eonworks.com"
   CATEGORY_="misc"
   PLATFORM_="Linux"
      SHELL_="bash"
 DISTRIBUTE_="yes"

# #############################################################################
# This program is distributed under the terms of the GNU General Public License

# HISTORY:
# 2001-10-12 - v1.0
# 2003-12-20 - v1.1 - major rewrite
# 2004-08-09 - v1.2 - added some more input checking, minor cosmetic changes

# TODO:
# - speed up header/footer generation


# ------------------------------------------- #
# user defined variables start
# ------------------------------------------- #

# add as much deciving code and comment variables as desired

# add/remove deceiving comments here
deceiving_comment[0]="# comment"
deceiving_comment[1]="# comment"

# add/remove deceiving code here, make sure it won't interfere with the 
# real code in the script to obfuscate
deceiving_code[0]="a=1; c=0"
deceiving_code[1]='f_() { while read l; do echo $l; done < $f ; }'

# ------------------------------------------- #
# user defined variables end
# ------------------------------------------- #

usage () {

echo >&2 "$NAME_ $VERSION_ - $PURPOSE_
Usage: $SYNOPSIS_
Requires: $REQUIRES_
Options:
    -c <n>, insert deceiving comments for every n line
    -d <n>, insert deceiving code for every n line
    -e <n1>-<n2>, prepend each line with a random number of spaces ranging
       from n1 to n2
    -f <file>, file to obfuscate
    -g <n1>-<n2>+<n3>-<n4>, insert gibberish header and footer of n2 lines
       long with each line n1 signs long, n3-n4 being range of characters
       to generate from. See the manual for more details.
    -h, usage and options (this help)
    -i, remove blank lines, comments, leading and trailing spaces and tabs
    -j <n1>-<n2>, insert n1 empty lines for every n2 line
    -m, manual
    -l, see this script"

    exit 1
}

manual () { echo >&2 "

NAME

    $NAME_ - $PURPOSE_

SYNOPSIS

    $SYNOPSIS_

DESCRIPTION

    $NAME_ is quite flexible and can obfuscate any type of shell script. The
    obfuscated script version is printed to stdo. The original script is not
    modified.

    Using $NAME_ options cleverly, one may fool more then just a casual intruder
    or snooper, and certainly make understanding of the obfuscated script harder
    and more time consuming.

OPTIONS

    -c <n>, insert deceiving comment for every n line. In the User Defined
       Variables section, you can add deceiving comments that will
       be added to the obfuscated script to further the obfuscation.

    -d <n>, insert deceiving code for every n line. In the User Defined
       Variables section, you can write deceiving code that will
       be added to the obfuscated script to further the obfuscation.
       Make sure that the deceiving code does not interfere with the
       real code. This option should be used with caution.

    -e <n1>-<n2> prepend each line with a random number of spaces ranging from
       n1 to n2. Basically specify a range from which random number of spaces
       will be generated.

    -f <file>, script to obfuscate

    -g <n1>-<n2>+<n3>-<n4>, insert gibberish header and footer of n1 lines long
       with each line n2 signs long. The n3-n4 refer to a range of signs from
       which to generate the random gibberish. The minimum n3 is 100 and the
       maximum n4 is 309. See string_randomSigns() for all elements of range.

    -h, usage and options (help)

    -i, remove blank lines, comments, leading and trailing spaces and tabs.
        As for comments, all lines starting with a #, or white space following
        a # are removed.

    -j <n1>-<n2>, insert n1 empty lines for every n2 line.

AUTHOR

    $AUTHOR_. Comments, suggestions and bug reports are welcome.

"; exit 1; }

# ===========================================================================
# ENVIRONMENT SETUP
# ===========================================================================

umask 077

# tmp file set up
tmp_dir=/tmp/${RANDOM}
mkdir $tmp_dir
tmp_1=$tmp_dir/tmp.${RANDOM}${RANDOM}
tmp_2=$tmp_dir/tmp.${RANDOM}${RANDOM}
tmp_3=$tmp_dir/tmp.${RANDOM}${RANDOM}

# signal trapping and tmp file removal
trap 'rm -f $tmp_1 $tmp_2 $tmp_3; rmdir $tmp_dir >/dev/null 2>&1' 0 
trap "exit 1" 1 2 3 15

# ===========================================================================
# LIB FUNCTIONS
# ===========================================================================


lang_fncArgCheck () {

    # argument checking
    local _args
    ((_args = $# - 2))
    if (( $1 > $_args ));then

        echo "function error: ${FUNCNAME}(): missing argument(s) passed to $(eval echo \${$#})(); requires $1 argument(s)"
        exit 1

    fi
 }


math_isInteger() {

    # argument checking
    lang_fncArgCheck 1 $1 $FUNCNAME

    case $1 in
       *[!0-9]*) return 1;;
       *) return 0;;
    esac

}

math_randFromRange() {

    # argument checking
    lang_fncArgCheck 2 $1 $2 $FUNCNAME
    
    math_isInteger $1
    [ $? != 0 ] && { echo >&2 argument ${1} passed to $FUNCNAME not an integer ; exit 1; }

    math_isInteger $2
    [ $? != 0 ] && { echo >&2 argument ${2} passed to $FUNCNAME not an integer ; exit 1; }

    local _rand=$((($RANDOM % ($2 - $1 + 1) + $1)))
    echo $_rand

}

string_returnSignNTimes() {

    # argument checking
    lang_fncArgCheck 2 $1 $2 $FUNCNAME

    local _c=0
    while (( $1 != $_c ));do
        echo -n $2
        ((_c++))
    done

}

string_randomSigns() {
    
    # argument checking
    lang_fncArgCheck 3 $1 $2 $3 $FUNCNAME
 
    local _sign

    _sign[100]=a
    _sign[101]=b
    _sign[102]=c
    _sign[103]=d
    _sign[104]=e
    _sign[105]=f
    _sign[106]=g
    _sign[107]=h
    _sign[108]=i
    _sign[109]=j
    _sign[110]=k
    _sign[111]=l
    _sign[112]=m
    _sign[113]=n
    _sign[114]=o
    _sign[115]=p
    _sign[116]=q
    _sign[117]=r
    _sign[118]=s
    _sign[119]=t
    _sign[120]=u
    _sign[121]=v
    _sign[122]=w
    _sign[123]=x
    _sign[124]=y
    _sign[125]=z
    _sign[126]=A
    _sign[127]=B
    _sign[128]=C
    _sign[129]=D
    _sign[130]=E
    _sign[131]=F
    _sign[132]=G
    _sign[133]=H
    _sign[134]=I
    _sign[135]=J
    _sign[136]=K
    _sign[137]=L
    _sign[138]=M
    _sign[139]=N
    _sign[140]=O
    _sign[141]=P
    _sign[142]=Q
    _sign[143]=R
    _sign[144]=S
    _sign[145]=T
    _sign[146]=U
    _sign[147]=V
    _sign[148]=W
    _sign[149]=X
    _sign[150]=Y
    _sign[151]=Z
    _sign[152]=0
    _sign[153]=1
    _sign[154]=2
    _sign[155]=3
    _sign[156]=4
    _sign[157]=5
    _sign[158]=6
    _sign[159]=7
    _sign[160]=8
    _sign[161]=9
    _sign[162]=0
    _sign[163]=1
    _sign[164]=2
    _sign[165]=3
    _sign[166]=4
    _sign[167]=5
    _sign[168]=6
    _sign[169]=7
    _sign[170]=8
    _sign[171]=9
    _sign[172]=0
    _sign[173]=1
    _sign[174]=2
    _sign[175]=3
    _sign[176]=4
    _sign[177]=5
    _sign[178]=6
    _sign[179]=7
    _sign[180]=8
    _sign[181]=9
    _sign[182]=0
    _sign[183]=1
    _sign[184]=2
    _sign[185]=3
    _sign[186]=4
    _sign[187]=5
    _sign[188]=6
    _sign[189]=7
    _sign[190]=8
    _sign[191]=9
    _sign[192]=0
    _sign[193]=1
    _sign[194]=2
    _sign[195]=3
    _sign[196]=4
    _sign[197]=5
    _sign[198]=6
    _sign[199]=7
    _sign[200]=8
    _sign[201]=9
    _sign[202]=0
    _sign[203]=1
    _sign[204]=2
    _sign[205]="¤"
    _sign[206]="%"
    _sign[207]="&"
    _sign[208]="]"
    _sign[209]="/"
    _sign[210]="("
    _sign[211]=")"
    _sign[212]="["
    _sign[213]="{"
    _sign[214]="}"
    _sign[215]="+"
    _sign[216]="?"
    _sign[217]="£"
    _sign[218]="*"
    _sign[219]="$"
    _sign[220]="+"
    _sign[221]="-"
    _sign[222]="~"
    _sign[223]=":"
    _sign[224]=";"
    _sign[225]="_"
    _sign[226]="="
    _sign[227]="¾"
    _sign[228]="½"
    _sign[229]="§"
    _sign[230]=","
    _sign[231]="."
    _sign[232]="¤"
    _sign[233]="%"
    _sign[234]="&"
    _sign[235]="]"
    _sign[236]="-"
    _sign[237]="("
    _sign[238]=")"
    _sign[239]="["
    _sign[240]="{"
    _sign[241]="}"
    _sign[242]="+"
    _sign[243]="?"
    _sign[244]="£"
    _sign[245]="*"
    _sign[246]="$"
    _sign[247]="?"
    _sign[248]="£"
    _sign[249]="!"
    _sign[250]="&"
    _sign[251]="?"
    _sign[252]="="
    _sign[253]="%"
    _sign[254]="."
    _sign[255]=":"
    _sign[256]=";"
    _sign[257]="¤"
    _sign[258]=" "
    _sign[259]=" "
    _sign[260]=" "
    _sign[261]=" "
    _sign[262]=" "
    _sign[263]=" "
    _sign[264]=" "
    _sign[265]=" "
    _sign[266]=" "
    _sign[267]=" "
    _sign[268]=" "
    _sign[269]="  "
    _sign[270]="  "
    _sign[271]="  "
    _sign[272]="  "
    _sign[273]="  "
    _sign[274]="  "
    _sign[275]="  "
    _sign[276]="  "
    _sign[277]="  "
    _sign[278]="  "
    _sign[279]="  "
    _sign[280]="  "
    _sign[281]="   "
    _sign[282]="   "
    _sign[283]="   "
    _sign[284]="   "
    _sign[285]="   "
    _sign[286]="   "
    _sign[287]="   "
    _sign[288]="   "
    _sign[289]="   "
    _sign[290]="    "
    _sign[291]="    "
    _sign[292]="    "
    _sign[293]="    "
    _sign[294]="    "
    _sign[295]="    "
    _sign[296]="    "
    _sign[297]="     "
    _sign[298]="     "
    _sign[299]="     "
    _sign[300]="     "
    _sign[301]="     "
    _sign[302]="     "
    _sign[303]="      "
    _sign[304]="      "
    _sign[305]="      "
    _sign[306]="      "
    _sign[307]="      "
    _sign[308]="      "
    _sign[309]="      "
               
    # checking for proper range
    if (( $2 > (( ${#_sign[*]} + 100 )) )) || (( $2 < 100 )); then
        echo "invalid range passed to ${FUNCNAME}, range is 100 - "$((( ${#_sign[*]} + 100 )))
        exit 1
    elif (( $3 > (( ${#_sign[*]} + 100 )) )) || (( $3 < 100 )); then
        echo "invalid range passed to ${FUNCNAME}, range is 100 - "$((( ${#_sign[*]} + 100 )))
        exit 1
    fi


    local _ac=0
    while (( $1 > _ac )); do
        local _num=${RANDOM:0:3}
        if (( $_num >= $2 )) && (( $_num <= $3 )); then
            echo -n "${_sign[$_num]}"
            ((_ac++))
        fi     
    done       
               
}

text_generateGibberish(){

    # argument checking
    lang_fncArgCheck 4 $1 $2 $3 $4 $FUNCNAME

    local _c=0
    while (( $2 != _c ));do
        echo $(string_randomSigns $1 $3 $4)
        ((_c++))
    done

}

text_listFile () {

    # argument checking
    lang_fncArgCheck 1 $1 $FUNCNAME

    # function
    local IFS=
    local _i
    while read -r _i; do
        printf "%s\n" "$_i"
    done < "$1"

}

# ===========================================================================
# LOCAL FUNCTIONS
# ===========================================================================

is_arg_integer() {

    math_isInteger $1 
    [ $? != 0 ] && { echo >&2 the argument to $2 option must be an integer ; exit 1; }

}

# ===========================================================================
# OPTION AND ARGUMENT HANDLING
# ===========================================================================

# option defaults
add_cmnt=off        # add deceiving comment for every n line
add_code=off        # add deceiving code for every n line
prepend=off         # prepend each line with a random n from within a range of
gibberish=off       # gibberish header
cleanup=off         # remove blank lines, comments, leading and trailing spaces and tabs
add_blanks=off      # insert n blanks for every n line

# args check
[ $# -eq 0 ] && { echo >&2 missing argument, type $NAME_ -h for help; exit 1; }

while getopts c:d:e:f:g:hij:k:lm options; do

    case $options in

        c) add_cmnt=$OPTARG ;;
        d) add_code=$OPTARG ;;
        e) prepend=$OPTARG ;;   
        f) file=$OPTARG ;;
        g) gibberish=$OPTARG ;;
        h) usage ;;
        i) cleanup=on ;;
        j) add_blanks=$OPTARG ;;
        l) more $0; exit 1 ;;
        m) manual ;;
       \?) echo invalid argument, type $NAME_ -h for help; exit 1 ;;
        
    esac

done
shift $(( $OPTIND - 1 ))

[ -f $file ] || { echo >&2 file $file does not exist ; exit 1; }
[ $file ] || { echo >&2 file input missing ; exit 1; }

# ===========================================================================
# MAIN
# ===========================================================================

touch $tmp_1 $tmp_2 $tmp_3
cp $file $tmp_2


# inserting deceiving code for every n line.
c=0
c2=0
if [[ $add_code != off ]]; then

    is_arg_integer $add_code -d
    oldifs=$IFS ; IFS=
    while read -r line; do # we need to read in raw mode, to disable backslash escaping...

        if (($c2 == $add_code)); then 
            # add deceiving comments for every n line
            if (( c < ${#deceiving_code[*]} )); then
                printf "%s\n" "${deceiving_code[c]}" >> $tmp_1
                ((c++))
            fi
            c2=0
        fi

        ((c2++))
        printf "%s\n" "$line" >> $tmp_1
    done < $tmp_2
    IFS=$oldifs
    mv $tmp_1 $tmp_2

fi


# removing blank lines, comments, leading and trailing spaces and tabs
if [[ $cleanup != off ]]; then

    sed -e '2,$ {/^ *$/d ; /^ *#/d ; /^[ \t] *#/d ; /*^/d ; s/^[ \t]*// ; s/*[ \t]$// ; s/ $//}' $tmp_2 > $tmp_1
    mv $tmp_1 $tmp_2

fi


# inserting deceiving comments for every n line
c=0
c2=0
if [[ $add_cmnt != off ]]; then

    is_arg_integer $add_cmnt -c
    oldifs=$IFS ; IFS=
    while read -r line; do

        if (($c2 == $add_cmnt)); then 
            # add deceiving comments for every n line
            if (( c < ${#deceiving_comment[*]} )); then
                printf "%s\n" "${deceiving_comment[c]}" >> $tmp_1
                ((c++))
            fi
            c2=0
        fi

        ((c2++))
        printf "%s\n" "$line" >> $tmp_1
    done < $tmp_2
    IFS=$oldifs
    mv $tmp_1 $tmp_2
fi


# inserting n empty lines for every n line
c2=0
if [[ $add_blanks != off ]]; then

    is_arg_integer ${add_blanks##*-} -j
    is_arg_integer ${add_blanks%%-*} -j

    oldifs=$IFS ; IFS=
    while read -r line; do
        
        if (( $c2 == ${add_blanks##*-} )); then 
            # add n blanks for every n line
            for (( c = 0 ; c < ${add_blanks%%-*} ; c++)); do
                echo >> $tmp_1
            done
            c2=0
        fi

        ((c2++))
        printf "%s\n" "$line" >> $tmp_1
    done < $tmp_2
    IFS=$oldifs
    mv $tmp_1 $tmp_2

fi

# prepending each line with a random number of spaces
if [[ $prepend != off ]]; then

    is_arg_integer ${prepend%%-*} -e
    is_arg_integer ${prepend##*-} -e

    c=0
    oldifs=$IFS ; IFS=
    while read -r line; do

        if (( c == 0)); then # skipping shebang
            printf "%s\n" "$line" >> $tmp_1
        else
            prep=$(math_randFromRange ${prepend%%-*} ${prepend##*-})
            printf "%b%s\n" $(string_returnSignNTimes ${prep} "\\040") "$line" >> $tmp_1
        fi

    ((c++))
    done < $tmp_2
    IFS=$oldifs
    mv $tmp_1 $tmp_2

fi


# adding gibberish header and footer
if [[ $gibberish != off ]]; then
                         
    signs=${gibberish%%+*} # n1-n2 - nr of signs per line and nr of lines
    range=${gibberish#*+}  # n3-n4 - range of signs to generate from

    is_arg_integer ${range%%-*} -g
    is_arg_integer ${range##*-} -g

    is_arg_integer ${signs##*-} -g
    is_arg_integer ${signs%%-*} -g

    # validating range input
    if (( ${range%%-*} < 100 || ${range%%-*} > 309 )) \
    || (( ${range##*-} > 309 || ${range##*-} < 100 )) \
    || (( ${range%%-*} > ${range##*-} ));then
        echo >&2 the n3-n4 integer arguments to the -g option must be between
        echo >&2 100 and 309, both inclusive. n3 must not be bigger then n4.
        exit 1
    fi 

    c=0
    oldifs=$IFS ; IFS=
    while read -r line; do

        if (( c == 0)); then # skipping shebang
            printf "%s\n" "$line" >> $tmp_1 
            d=${gibberish%%-*} # to make the first line of same length as other lines
            echo : "'"$(string_randomSigns $(((d-=3))) ${range%%-*} ${range##*-}) >> $tmp_3
            text_generateGibberish ${signs%%-*} ${signs##*-} ${range%%-*} ${range##*-} >> $tmp_3
            echo -e $(string_returnSignNTimes ${signs%%-*} "\\040")"'" >> $tmp_3
            text_listFile $tmp_3 >> $tmp_1
        else
            printf "%s\n" "$line" >> $tmp_1
        fi

        ((c++))
    done < $tmp_2
    text_listFile $tmp_3 >> $tmp_1
    IFS=$oldifs
    mv $tmp_1 $tmp_2

fi

text_listFile $tmp_2