Patent ID: 10630462

Abstract:
A method for implementing a pseudo-random function (PRF) using a white-box implementation of a cryptographic function in N rounds, including: receiving an input to the PRF; receiving a cryptographic key in a first round; encrypting, using the white-box implementation of the cryptographic function and the cryptographic key, an input message that is one of M possible input messages based upon a portion of the input to produce a first output; for each succeeding round: encrypting, using the white-box implementation of the cryptographic function and an ith cryptographic key, further input messages that are one of M possible input messages based upon a further portion of the input to produce an ith output, wherein the ith cryptographic key is the output from the preceding round, wherein the white-box implementation of the cryptographic function only produces a correct output for the M possible input messages and produces an incorrect output for input messages that are not one of the M possible input messages.