Re: [Haskell-cafe] Digests

On 12/03/2010 10:48 AM, Serguey Zefirov wrote:

2010/12/3 Permjacov Evgeniy :

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Most of the time you can get away with usual block ciphers (and even with weaker parameters). There is a scheme that transforms block cipher into hash function: http://en.wikipedia.org/wiki/CRHF#Hash_functions_based_on_block_ciphers */me wrote it into to_read list. The problem is, however, that block ciphers are quite unfriendly to plain word8 streams. It is not a deadly problem, but i'd like to avoid block collections. All one-way hashes do block collections. This is unavoidable. Why ? Is there some math behind this proposition ?