Patent ID: 8566609
Filing Date: 2013-10-22
Classification: G09C,H04L

Abstract:
1. A method for protecting the integrity of data ciphered by a ciphering algorithm providing at least one intermediary state meant to be identical in ciphering and deciphering, comprising: sampling, by a processing unit of an integrated circuit, several intermediary states resulting from ciphering of the data; generating, by the processing unit, several signatures based on the several sampled intermediary states; gathering, by the processing unit, the several signatures and processing the gathered signatures to obtain a result; and providing, by the processing unit, the result of processing the gathered signatures in addition to the ciphered data, wherein the result is stored, together with the ciphered data, in a memory external to the integrated circuit executing the ciphering algorithm, wherein the gathered signatures are combined by an XOR function with part of the data to be ciphered, and wherein the result is stored together with the ciphered data in the memory.