Re: Hash cash keys

Michael Rogers wrote:
> the data must be 
> accompanied by a string whose hash shares a b-bit prefix with the hash 
> of the public part of the key.

Sorry for replying to myself but I just spotted a problem: you could 
build up a dictionary of strings for all b-bit prefixes and reuse them. 
So instead of hash(string) matching hash(public_part) in the first b 
bits, hash(xor(string,public_part)) should match hash(public_part) in 
the first b bits.

Cheers,
Michael