Jitter attack protection circuit

A data storage device, comprising:

• a non-volatile memory (NVM);
• a controller circuit configured to direct a transfer of data between the NVM and a host device, the controller circuit comprising a cryptographic processing circuit configured to perform a cryptographic function on a set of input data to generate a corresponding set of transformed output data, the cryptographic processing circuit receiving an input signal from an input line to facilitate execution of the cryptographic function;
• and
• a monitor circuit configured to monitor the input signal at a connection point upstream of the cryptographic processing circuit and to output a disable signal to the cryptographic processing circuit to temporarily disable the cryptographic function on the input data for a predetermined elapsed period of time determined by a timer circuit responsive to a detection of time-varying changes to the input signal indicative of a potential jitter attack, the cryptographic processing circuit prevented by the monitor circuit from performing the cryptographic function on any input data while disabled, the cryptographic processing circuit enabled by the monitor circuit to resume the cryptographic function at a conclusion of the predetermined elapsed period of time.

A method comprising:

• supplying an input signal to a cryptographic processing IC;
• using the cryptographic processing IC to execute a cryptographic function on a set of input data to generate a corresponding set of transformed output data;
• monitoring the input signal during the execution of the cryptographic function at a connection point upstream of the cryptographic processing IC;
• and
• disabling the execution of the cryptographic function responsive to a detection of time-varying changes to the input signal at the connection point indicative of a potential jitter attack, the cryptographic processing IC prevented from performing the cryptographic function on any input data while the cryptographic processing IC remains disabled.