11

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
  • 131
  • 3
Blanco
  • 1,622
  • 1
  • 10
  • 20

2 Answers2

13

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
  • 27,820
  • 1
  • 66
  • 83
7

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
  • 131
  • 3
Geoffroy Couteau
  • 19,919
  • 2
  • 46
  • 68