Maxim Integrated Products, Inc.
Systems and methods for masking RSA operations

Abstract:

Presented are systems and methods for protecting secret data that is stored in memory to prevent unauthorized access and data manipulation. Various embodiments may be applied to hide or mask an RSA exponent used for public key cryptography and stored in a cryptographic hardware block that uses a non-erasable working memory for computations. In certain embodiments, masking RSA exponents is accomplished by a two-step process that combines a specifically calculated, random and secret value with the secret exponent. The random value is stored in an erasable memory, such that in case of attack, both the erasable memory and the non-erasable memory do not leak any embedded secrets. The additional expenditure of memory resources only insignificantly affects system performance.