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Does the existence of a PRF/PRG/one way function imply the existence of a hash function? I did not find a proof of the existence of a cryptographic hash function, so I want to know whether it is based the same axiom (the PRG axiom)?

psmears
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Blanco
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2 Answers2

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There is a black-box separation between one-way functions and collision resistant hash functions. This was proven at Eurocrypt 1998 by Dan Simon, in the paper entitled Finding collisions on a one-way street: Can secure hash functions be based on general assumptions?. Of course, this doesn't mean that it's not possible using non-black-box reductions, but no one knows how to do this.

Yehuda Lindell
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To complement Yehuda Lindell's answer, if you need a property weaker than collision resistance (e.g. target collision resistance), then the existence of such hash function is equivalent to the existence of one-way functions, which is equivalent to the existence of prgs.

psmears
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Geoffroy Couteau
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