Verifiable random functions with Boolean function constraints

Verifiable Random Functions

We efficiently combine unpredictability and verifiability by extending the Goldreich–Goldwasser–Micali construction of pseudorandom functions fs from a secret seed s, so that knowledge of s not only enables one to evaluate fs at any point x, but also to provide an NP-proof that the value fs(x) is indeed correct without compromising the unpredictability of fs at any other point for which no such...

Weak Verifiable Random Functions

Verifiable random functions (VRFs), introduced by Micali, Rabin and Vadhan, are pseudorandom functions in which the owner of the seed produces a public-key that constitutes a commitment to all values of the function and can then produce, for any input x, a proof that the function has been evaluated correctly on x, preserving pseudorandomness for all other inputs. No public-key (even a falsely g...

Constrained Verifiable Random Functions

We extend the notion of verifiable random functions (VRF) to constrained VRFs, which generalize the concept of constrained pseudorandom functions, put forward by Boneh and Waters (Asiacrypt’13), and independently by Kiayias et al. (CCS’13) and Boyle et al. (PKC’14), who call them delegatable PRFs and functional PRFs, respectively. In a standard VRF the secret key sk allows one to evaluate a pse...

Abstracting numeric constraints with Boolean functions

Verifiable Random Functions from Weaker Assumptions

The construction of a verifiable random function (VRF) with large input space and full adaptive security from a static, non-interactive complexity assumption, like decisional Diffie-Hellman, has proven to be a challenging task. To date it is not even clear that such a VRF exists. Most known constructions either allow only a small input space of polynomially-bounded size, or do not achieve full ...