PUF authentication and key-exchange by substring matching

摘要

Mechanisms for operating a prover device and a verifier device so that the verifier device can verify the authenticity of the prover device. The prover device generates a data string by: (a) submitting a challenge to a physical unclonable function (PUF) to obtain a response string, (b) selecting a substring from the response string, (c) injecting the selected substring into the data string, and (d) injecting random bits into bit positions of the data string not assigned to the selected substring. The verifier: (e) generates an estimated response string by evaluating a computational model of the PUF based on the challenge; (f) performs a search process to identify the selected substring within the data string using the estimated response string; and (g) determines whether the prover device is authentic based on a measure of similarity between the identified substring and a corresponding substring of the estimated response string.

主权项

1. A method for operating a device to verify the authenticity of a communicating party, the method comprising:
receiving a data string from the communicating party, wherein the data string is generated by the communicating party by:
(a) submitting a challenge to a physical unclonable function to obtain a response string,(b) selecting a substring of predetermined length from the response string,(c) injecting the selected substring onto a continuous range of bit positions within the data string, wherein a start position of the selected substring within the data string is determined by a variable number that is not communicated to said device, and(d) injecting random bits into bit positions of the data string not assigned to the selected substring, wherein said generating the data string also includes randomly selecting the variable number; generating an estimated response string by evaluating a computational model of the physical unclonable function based on the challenge; performing a search process to identify the selected substring within the data string using the estimated response string; determining whether the communicating party is authentic based on a measure of similarity between the identified selected substring and a corresponding substring of the estimated response string, wherein said generating, said performing and said determining are performed by digital circuitry.