How do I design a cryptographic hash function?

Posted by Eyal on Stack Overflow See other posts from Stack Overflow or by Eyal
Published on 2010-05-26T08:37:48Z Indexed on 2010/05/26 8:41 UTC
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Filed under:

hash

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cryptography

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one-way

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feistel

After reading the following about why one-way hash functions are one-way, I would like to know how to design a hash function.

http://stackoverflow.com/questions/1038307/help-me-better-understand-cryptographic-hash-functions/1047106#1047106

Before everyone gets on my case: Yes, I know that it's a bad idea to not use a proven and tested hash function. I would still like to know how it's done.

I'm familiar with Feistel-network ciphers but those are necessarily reversible, horrible for a cryptographic hash. Is there some sort of construction that is well-used in cryptographic hashing? Something that makes it very one-way?

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