Brutforce too slow? / Increment-Problems [Solved]
#1
Question 
Hello everyone,

bruteforcing with the 7970 and only ?d seems a bit slow here.

oclHashcat64.exe --gpu-accel=32 --gpu-loops=32 --gpu-temp-abort=90 -m 2500 -a 3 -i --increment-min=8 --increment-max=9 -1 ?d -2 ?d -3 ?d -4 ?d test.hccap

Gives me:
Input.Mode: Mask (?1?2?2?2?2?2?2?3) [8]
Time.Estimated: 1 year, 135 days
Speed.GPU.#1: 129.0 kH/s
HWMon.GPU.#1: 92% Util, 68c Temp, 67% Fan

I have defined -1 to -4 since the generated mask used -1, -2 and -3 even when I only defined -1.
Since haschat should try 00000000 to 999999999, the estimated duration seems a little long for me.

Where is my mistake?
Thanks in advance Smile

EDIT:
Solved the problem:
Increment does work with custom masks, but only if it has to shorten them. Thus the mask provided has to be at least as long as the increment-max value (or longer).
#2
Its using the default mask because you didnt provide one.

Code:
oclHashcat64.exe --gpu-accel=32 --gpu-loops=32 --gpu-temp-abort=90 -m 2500 -a 3 ?d?d?d?d?d?d?d?d?d test.hccap --pw-min 8 --increment
#3
Just to clarify radix's point:
You "defined" 4 different character sets that can be used in a mask, but you didn't define the mask itself.
The mask is shown in its own position without using the numbered switches.
#4
and you should use -u 4096 -n 32 for optimal speed (not -u 32)
#5
Thanks for the fast reply ^^

I think I have solved the problem:

Code:
oclHashcat64.exe --gpu-accel=32 --gpu-loops=32 --gpu-temp-abort=90 -m 2500 -a 3 -i --increment-min=8 --increment-max=9 -1 ?d test.hccap ?1?1?1?1?1?1?1?1

This way it says "13 Minutes", which sounds way more reasonable. But I am still not getting the whole increment thing here. If I set min to a higher value, it won't start ("Mask is too short"), and if I set max to 9 or bigger, it still ends after the lengh of 8.

And: How are -u and -n linked? This thread mentiones -u 800 and -n 1024, yet you use a higher value for -u, but a lower for -n?

Thank you all again ^^
#6
you don't need to define a custom character set for a single character class. instead of
Code:
-1 ?d ?1?1?1?1?1?1?1?1
you can simply do
Code:
?d?d?d?d?d?d?d?d
of course since your mask is eight characters, it will always end after a length of 8 regardless of what you set --increment-max to. and since wpa has a minimum of 8 characters, it's not possible to set --increment-min lower than 8.
so to brute force digits length 8 & 9, your attack would simply be
Code:
-i --increment-min 8 ?d?d?d?d?d?d?d?d?d
that thread you linked to mentions -n 800 -u 1024, not -u 800 -n 1024. you have it backwards. for wpa you absolutely want to use -u 4096 and a low -n value.
#7
The thing is: All this is part of a small script I am writing that should -in theory- make launching hashcat a little easyier. And to be a little more flexible, it asks the user to define the charset which will be used as said custon charset -1. That is also why I want to stick to a ?1?1...-mask if possible.
Now I have provided a 8x?1 mask at the end, since -as you have also mentioned- the minimum lengh is always 8 characters, but if I set increment min to a higher value, it still complains that the mask is too small. Seeing your example now, I'd assume that the provided mask always has to be as long as my value for increment-max, right? So if I have min=9 and max=12, it would be 12x?1 and then cut down by hashcat for each new step.

Oh sorry, I was tired back then Big Grin So I have to set the accelleration (-n) to a low value (32 as it has been recommended here) and the loops (-u) to a high value such as 4096. Although I will set this the way you recommended, I am curious what those settings exactly do and why it is the best to set them in such a way.

Sorry for all these questions and problems, but (obviously) I am quite new to all this. ^^'
Thus thank you all for your kindness and patience Smile

PS: If you like, I can provide the whole script (.bat since I won't get hashcat running on my The-Distribution-Which-Does-Not-Handle-OpenCL-Well (Kali)-Partition, but that's another story ) as soon as it works fine.
#8
Sorry for double-posting, but as I have mentioned in my first post the problem has been solved:
Increment does not add characters to a custom mask. Instead it cuts in down to the lenght needed. Thus for increment-min:8 and increment-max:12 the mask must be at least 12 characters long.
In my case -to keep the settings as flexible als possible- I have used a 40x?1 mask that is currently being cut down to 9 to 12. Everything else works fine.

With -n 32 and -u 4096 I get something about 140 kH/s on my 7970. Is there still room for improvement without OCing my card?

Btw: This is the script I have mentioned:
http://pastebin.com/BJ71efds
#9
140 kH/s on 7970 sounds perfect without overclock
#10
(01-13-2014, 12:04 AM)atom Wrote: 140 kH/s on 7970 sounds perfect without overclock

Ok, thanks for the info. Smile