GPU Password Cracking

1. Not for noobs… GPU Password Cracking

2. What even is a GPU? • A GPU (Graphics Processing Unit) is piece of hardware(single chip processor) primarily used for computing 3D functions. • Such things are lighting effects, object transformations, and 3D motion. www.techterms.com/definition/gpu

3. CPU vs. GPU • Simple look at architecture

4. CPU Vs. GPU speeds

5. Why is this important? • Currently the first 80 of the top 500 super computers are there due to (general purpose) GPGPUs. This shows how powerful GPUs have become and their usability.

6. What choices do we have?

7. Nvidia • These are slightly more expensive graphics cards. • Nvidia is required if your attempting to get on the top 500 supercomputers list. (this is due to CUDA) • Higher clock shader clock speeds, along with more complex ALUs

8. ATI • ATI is competing technology against Nvidia. • Has potential to be faster than Nvidia in password cracking applications. • Cheaper • Slower shader clock speeds, but more ALUs on chip

9. Cloud Based and DistributedNetworks • On solution is to pay for time on cloud based services. Ex. (Amazon AWC/ EC2, Nimbix, Peer1, Penguin) • Join a Distributed network • Distributed.net • Folding@home • Boinc (freerainbowtables.net) • SETI@home

10. What is feasible? • The cost of running a cloud based service is more for those with deeper pockets. • Instead a locally hosted machine is more affordable

11. That leaves us with Nvida Vs. ATI • The most common question…. WHICH IS BETTER?!

12. Nvidia cant compete… • Nvidia design for example on the GTX 590 has 2 GTX 580s on a single card. • This means it has 512 cores x 2 = 1024cores * 8 cells = 8192 steams. • While this is a lot of steams (meaning more password cracking pipelines) mapping to each stream is done by only the first cell.

13. This does not utilize the GPU as much as it can be. • Another blow is that the BIT_ALIGN_INT operator must be emulated on Nvidia cards requiring 2 shifts + 1 add • This means Nvidia cards must use 3 instructions instead of 1 for some hashing functions as compared to ATI cards.

14. Comparisons • ATI Radeon HD6990 • 3072 ALUs x 830 MHz = 2550 billion 32-bit instructions per second • Nvidia GTX 590 • 1024 ALUs x 1214 MHz = 1243 billion 32-bit instructions per second

15. Winner? • As seen in the previous slide ATI takes the cake for password cracking applications. • Due to BIT_ALIGN_INT, more ALUs, and cost to power efficiency, ATI has approximately 3x-5x performance boost. en.bitcoin.it

16. What even is? • The differences between the card architecture translates into a direct increase in password cracking speed for ATI cards. • Simpler ALUs at lower clocks == less energy consumption.

17. Scalability • Adding another GPU actually increases how many password can be cracked more than 100% Ex. 2x Radeons HD6990 != 2550 billion instructions per second * 2 Its actually faster! (minutely though)

18. Password Cracking Software • GPU cracking • Oclhashcat • IghashGPU • WhitePixel • Extreme GPU Bruteforcer • CUDA – MULTIFORCER • Lightning hash cracker

19. Distributed solutions • LastBit • Elecomsoft • Durandural

20. Password cracker of choice • OclHashcat • Advanced mask processing • Character per position attacks (using **clues**) • Rule engine • Manipulate wordlists based on rules on the fly • Hybrid dictionary + mask attacks • Use wordlists and masks together to hit more passwords • Finger Printing attack • Psychology of humans based attack

21. Mask Engine • ?d – Digits • ?l – lower case alpha • ?u – uppercase • ?s – symbols • ?h – hex 0xc0 – 0xff • ?D-German alphabet • ?F-French alphabet • ?R-Russian alphabet

22. Lets try it out. • We will manipulate the string and use a mask to hit our hashes ichidor Command: echo ichidor | expander | sort -u > outfile

23. Common human convention is to append numbers within the string • Some examples of wordlist + ‘?d?d’ • Chido06 • Dori09 • hido30 • chidori15 • ichi91 • hidori24