how to limit password character length
#1
Hi,

I'm using this command to find my password on mac Yosemite

Code:
./hashcat-cli64.app -m 7100 hash.txt wordlist.txt

And it was successful, however it took a little bit long.

What if I know exactly how many chacracter my password have. In this case, it's 6 characters ("tobein"). How can I tell hashcat not to try further than that?
#2
http://hashcat.net/wiki/doku.php?id=rule_based_attack

You could use '6 or <7
#3
(03-02-2015, 06:08 AM)epixoip Wrote: http://hashcat.net/wiki/doku.php?id=rule_based_attack

You could use '6 or <7

Like this below?

Code:
./hashcat-cli64.app -m 6 7100 hash.txt wordlist.txt
#4
No, like this:

Code:
echo "<7"  >under_7.rule
./hashcat-cli64.app -m 7100 hash.txt wordlist.txt -r under_7.rule
#5
Ok. I'm still checking
#6
Works here:

Code:
epixoip@token:~$ echo "<7" >under_7.rule

epixoip@token:~$ cat under_7.rule
<7

Did you forget the quotes?
#7
I see. It's working now. But something interesting that I want to clarify with you.

The limit character method should work faster than no limit right? However the limit method reports the longer estimated time than without using

I attached the screen shots for your reference.


Attached Files
.jpg   limit character method.jpg (Size: 58.41 KB / Downloads: 15)
.jpg   normal method.jpg (Size: 36.01 KB / Downloads: 12)
#8
Too much overhead checking the length of each candidate. You can try using the other rule instead. Edit the rule file and replace <7 with '6 and see if that helps.
#9
(03-02-2015, 06:54 AM)epixoip Wrote: Too much overhead checking the length of each candidate. You can try using the other rule instead. Edit the rule file and replace <7 with '6 and see if that helps.

I just tried that. The estimated time now is still the same as "<7"


Attached Files
.jpg   limit 6 character.jpg (Size: 58.28 KB / Downloads: 5)
#10
Yeah, slightly faster but not near as fast as not filtering at all. String manipulation is just too slow.

So in this case what I'd suggest doing is pre-filtering your wordlist.

Code:
awk 'length < 7' wordlist.txt >wordlist_6.txt

Then run wordlist_6.txt instead of wordlist.txt