US 10,873,446 B2 · False key-controlled aggressive voltage scaling

Abstract

Methods and systems are provided for single false key-controlled (SFKC) aggressive voltage scaling (AVS) and multiple parallel false key controlled (MPFKC) AVS countermeasure systems. When a plaintext value is input into a cryptographic circuit for modification by a correct key, power supplied to the cryptographic circuit is scaled based on a result of the plaintext value modified by a false key or by a random number of parallel false keys, which occurs during every clock cycle. The scaling may be triggered when the operating frequency of the cryptographic circuit falls below a threshold, which indicates occurrence of a leakage power attack. A key that is detectable within a power trace of the scaled power provided to the cryptographic circuit, with a highest correlation coefficient relative to a known key, is a key other than the correct key. The MPFKC AVS technique also inhibits unriddling of the input power scaling scheme.

Claims18

Dependent claims

A system for false key-controlled voltage scaling, the system comprising:

a power supply comprising an analog input, and an output that provides power to a cryptographic circuit;
an electronic controller operatively coupled to the analog input of the power supply, wherein the electronic controller:
receives a plaintext value that is also input to the cryptographic circuit, wherein the cryptographic circuit modifies the plaintext value with a correct key;
controls, based on a result of the plaintext value modified by a first false key, the analog input to scale the power provided via the output of the power supply to the cryptographic circuit;
and
wherein the electronic controller selects a random number of parallel false keys, and for every selected parallel false key, modifies an instance of the plaintext value with a respective one of the selected parallel false keys during a same clock period for determining a magnitude of the scaling of the power provided to the cryptographic circuit.

3 more elements

A method for false key-controlled voltage scaling, the method comprising:

providing power to a cryptographic circuit via an output of a power supply;
receiving by an electronic controller operatively coupled to an analog input of the power supply, a plaintext value that is also input to the cryptographic circuit, wherein the cryptographic circuit modifies the plaintext value with a correct key;
controlling, by the electronic controller and based on a result of the plaintext value modified by a first false key, the analog input to scale the power provided to the cryptographic circuit;
and
wherein the electronic controller selects a random number of parallel false keys, and for every selected parallel false key, modifies an instance of the plaintext value with a respective one of the selected parallel false keys during a same clock period for determining a magnitude of the scaling of the power provided to the cryptographic circuit.

2 more elements

Dependencies are inferred from the claim text.

False key-controlled aggressive voltage scaling

Life of this patent

False key-controlled aggressive voltage scaling

Life of this patent

Abstract

Claims18