First off, you guys are awesome here, I have always got help with what i was trying to accomplish. I just hope that one day I can be as good as a programmer as alot of yall :)
Ok to the point. I am using perl (active state perl latest build 64 bit). I have tried over and over to accomplish this. I have a file. I open the file and then binmode it.
In the beginning of this file there are static references to the actual data. The references are as follows: file location, and file size. I need to setup a script that will find the file location and the filesize, then seek to that spot in the file and extract it. I can setup almost everything myself, but I just cannot get my head around how to accomplish this. here is a sort of flow chart if you will:
open file
binmode file
seek to static reference offset (file location) in file
read a predefined byte length
seek to static reference offset (file size) in file
read a predefined byte length
use that info (file location) to goto to the actual data.
then extract (file size)
Hopefully you understand what i am trying to accomplish. Its sort of like a dynamic extractor. It extract data based of the information it finds in the static references.
EDIT:
Thank you all for helping. i finally got it to work like this:
open(my $infile, "<", "./file") or die "Cannot open file: $!";
# GET FILESIZE AND LOCATION
$buffer1 = '';
$buffer2 = '';
seek $infile, 0x15, 0;
read $infile, $location, 0x03;
seek ($infile, 0x1D, 0);
read ($infile, $filesize, 0x03);
$location =~ s/(.)/sprintf("%02x",ord($1))/eg;
$filesize =~ s/(.)/sprintf("%02x",ord($1))/eg;
# GET FILENAME
seek $infile, 0x20, 0;
read $infile, $filename, 0x25;
$filename =~ s/\0*$//g;
print $filename, "\n";
my $directory = "extracted\\";
system "mkdir $directory";
# EXTRACT FILE
open($newfile, '>', "extracted//$filename");
sysseek $infile, hex($location), 0;
sysread $infile, $new, hex($filesize);
syswrite $newfile, $new;
Thanks to everyone who took their time to help me :)
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