hashcat Forum

here you can find an interesting challenge about cracking a bitcoin "brain wallet". 
Privatekey is derived from a passphrase is 8 characters long, only alphanumerics. For example, 'b234FEzz'. the salt is [email protected]

I've found a github repo tryng to brute force using a CPU only GO script, any idea how could perform hascat with an ad-hoc algorithm?

here hashing detail:
s1 = scrypt(key=(passphrase||0x1), salt=(salt||0x1), N=218, r=8, p=1, dkLen=32)

s2 = pbkdf2(key=(passphrase||0x2), salt=(salt||0x2), c=216, dkLen=32, prf=HMAC_SHA256)
keypair = generate_bitcoin_keypair(s1 ⊕ s2)

whats that?

Hashcat doesn't support ad-hoc algorithms.

John the Ripper supports ad-hoc algorithms, but only using certain components. Direct support would be required. This thread might be informative.

I have no experience with it, but Brainflayer may also be of use.

i think that would be dope to create an hashcat algo for 20 BTC ^,^

I've already looked into this challenge once before, as well as worked on attack code for it. The keyspace is VERY large for the algorithm so it become a bit of an issue if you try and attack it.

(10-06-2017, 05:20 PM)Chick3nman Wrote: [ -> ]I've already looked into this challenge once before, as well as worked on attack code for it. The keyspace is VERY large for the algorithm so it become a bit of an issue if you try and attack it.

its maybe huge, but if we combined gpu powa and solve it we can then split the reward.

I see as a major issue the low hashrate reachable against scrypt algorithm, considering also the parameter r=8 slowing all down dramatically. Since the challenge'll close the 1st Jan , we probably would have some chance only with something like 20 MH/s

i have a nice rig x8 1080, that i can contribute to the task, but some one as to make an algo first

Could you use a Litecoin ASIC miner since they use scrypt?