USING WHITE-BOX IN A LEAKAGE-RESILIENT PRIMITIVE

• Main Authors: HOOGERBRUGGE, Jan, MURRAY, Bruce, BOS, Joppe Willem, MICHIELS, Wilhelmus Petrus Adrianus Johannus, VENTZISLAV, Nikov, MEDWED, Marcel
• Format: Patent
• Language: English; French; German
• Published: 24.03.2021
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHICCOMMUNICATION

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 i th cryptographic key, further input messages that are one of M possible input messages based upon a further portion of the input to produce an i th output, wherein the i th 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.