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I like crypto. Need I say more?


May
11
revised Finding hash almost-collisions
deleted 123 characters in body
May
10
comment Finding hash almost-collisions
@0xFE, if the problem is massively parallelizable, then hardware can make a huge difference. See cs.rit.edu/~ark/parallelcrypto/sha3test01 for more info (including some code).
May
10
revised Finding hash almost-collisions
deleted 254 characters in body
May
10
comment Finding hash almost-collisions
@CodesInChaos, this is good. I need all the checking of my math I can get. You are right, it should be $2^{51}$ for a $.5$ probability. Threw in a little birthday problem math by mistake.
May
10
comment Cryptography based upon neural networks
@D.W., is right. The only reason I wrote an answer is because it wouldn't fit in a comment.
May
10
answered Cryptography based upon neural networks
May
10
revised Finding hash almost-collisions
added 5 characters in body
May
10
comment Is the DES algorithm in OPENSSL random?
@vikkyhacks,Depending on your application, hiding the salt (much like hiding an IV or nonce) is unnecessary. The salt ensures the key is different from execution to execution making it such that the ciphertext is different even for the same plaintext/password. See also.
May
10
comment Finding hash almost-collisions
One problem I ran into when doing this is that the output of the Skein library I was using Skeinfish wasn't the same as what XKCD reported. They were apparently using PySkein which had a newer tweak to the key schedule constants. It took me a while to figure this out.
May
10
revised Finding hash almost-collisions
added 70 characters in body
May
10
comment Is the DES algorithm in OPENSSL random?
@vikkyhacks, I haven't looked at the code, but I imagine that the first few bytes immediately after SALTED_ in the ciphertext is the salt.
May
10
answered Finding hash almost-collisions
May
10
comment Is the DES algorithm in OPENSSL random?
Cleaned up some comments from a previous version of answer. Thanks @StephenTouset for pointing out my flaw.
May
10
revised Is the DES algorithm in OPENSSL random?
deleted 50 characters in body
May
10
revised Is the DES algorithm in OPENSSL random?
added 28 characters in body
May
10
answered Is the DES algorithm in OPENSSL random?
May
10
comment Cryptography based upon neural networks
Have you done a background/lit. search? If so, would you mind sharing some of the results you've come across. For me in particular and probably others here, neural crypto is something I've never heard of.
May
8
awarded  rsa
May
7
revised How to hash a structure that needs to include that hash's outcome?
added 184 characters in body
May
7
comment How to hash a structure that needs to include that hash's outcome?
@JohnDeters, I totally agree and should have put that in the answer.