02-04-2013, 05:02 AM
Hi all,
I'm completely unsure where to put this so I figured this would be the correct place. How would I integrate a custom SHA1 algo into hashcat to use GPU? The algorithm I am trying to brute force uses SHA1, however it also utilizes key stretching. It hashes into itself 10 times, while adding the KEY.
It starts with: KEY--salt--password-KEY
Then the next time it's: lasthash--salt-password--KEY, and it keeps using the hash from before 10 times.
I've created a perl script to use a wordlist:
However, since it's 10 iterations.. it's very slow. So I wanted to utilize GPU. Is this possible with hashcat?
I'm completely unsure where to put this so I figured this would be the correct place. How would I integrate a custom SHA1 algo into hashcat to use GPU? The algorithm I am trying to brute force uses SHA1, however it also utilizes key stretching. It hashes into itself 10 times, while adding the KEY.
It starts with: KEY--salt--password-KEY
Then the next time it's: lasthash--salt-password--KEY, and it keeps using the hash from before 10 times.
I've created a perl script to use a wordlist:
Code:
#!/usr/bin/perl
use strict;
use Digest::SHA1;
die "usage: $0 <hash list> <dictionary> <skey>\n" unless @ARGV == 3;
my $skey = $ARGV[2];
open(H, "<$ARGV[0]") || die "bad hash list";
my $i = 0;
$|++;
my $time = time;
while (<H>)
{
$i++;
my $sec = time - $time;
$time = time;
print "\rTesting hash $i... ($sec secs/hash)";
chomp;
my ($h, $s) = split(':');
open(W, "<$ARGV[1]") || die "bad pass list";
while (<W>)
{
chomp(my $w = $_);
my $x = "--$s--$w--$skey";
my $i = $skey;
$i = Digest::SHA1::sha1_hex($i . $x) for 1 .. 10;
if ($i eq $h)
{
print "\rgot: $h => $w\n";
last;
}
}
close W;
}
__DATA__
for (int b = c_start_block; b < blks; b++) {
write("Processing block: %d\n", b);
foreach (words[b * BLKSIZE..(b + 1) * BLKSIZE - 1], w) {
foreach (hashes; h; s) {
x = "--" + s + "--" + w + "--" + skey;
i = skey;
for (n = 0; n < 10; n++) {
i = String.string2hex(Crypto.SHA1.hash(i + x));
}
if (i == h) {
write("%s %s\n", h, w);
f_cracked->write("%s:%s\n", h, w);
}
}
}
}However, since it's 10 iterations.. it's very slow. So I wanted to utilize GPU. Is this possible with hashcat?
