The countermeasures against side channel analysis of the encryption algorithm using Boolean operations and arithmetic operations

摘要

The present invention relates to a countermeasure method for side channel analysis to a cryptographic algorithm using Boolean operations and arithmetic operations. In order to protect cryptographic algorithms that combine Boolean and arithmetic instructions for primary side channel analysis, it is necessary to perform a conversion between Boolean masking and arithmetic masking. The present invention proposes a new conversion method from arithmetic masking to Boolean masking using only one pre-calculated table T. The table T is configured to switch from arithmetic masking to Boolean masking k-bit nibbles with k-bit nibbles for integers having a size greater than k bits while adding the masked carry number from modular addition to nibbles. Is done.