Providing cpu smoothing of cryptographic function timings

Abstract

An approach that smoothes a cryptographic function's timing footprint is presented. A processor includes a 'function timing smoother' that smoothes out spikes in the amount of time that a particular cryptographic function requires to execute. When a cryptographic function executes, the function timing smoother tracks the amount of time that the cryptographic function executes (current execution time) and compares the time with the amount of time that the same cryptographic function took for a previous execution (previous execution time). When the current execution time is less than the previous execution time, the function timing smoother adds instructions or varies an execution unit's clock speed in order to increase the cryptographic function's current execution time. Using this approach, a malicious user is not able to decipher sensitive information from the cryptographic function's timing footprint.