Bugtraq mailing list archives

Re: [lists] Combining Hashes


From: Elliott Bäck <ecb29 () cornell edu>
Date: Sat, 19 Feb 2005 00:14:27 -0500

Kent Borg wrote:

I admit I don't know why this might be significantly better than
d1+d2, I was hoping someone here would.

I think there are a couple things going on here. First, since + is concatenation, SHA-1(SHA-1(data)+data+MD5(data)) provides an input to the hash that is three times as long as before. I'm also not familiar with the inner workings on SHA-1 and MD-5, but the second idea here is that they both represent (somewhat) orthogonal solution spaces, so that the concatenation of both of them adds more dimensionality and therefore more uniqueness.

However, I am just guessing here off the top of my head.

Thanks,
Elliott C. Bäck

607-229-0623
http://elliottback.com


Current thread: