Method and module for updating code of encryption algorithm, method and module for generating seed, and encryption processor and recording medium for these methods

Abstract

This method for renewing the code of an algorithm comprises: receiving (122) a randomly drawn seed whose size in terms of number of bits, is at least four times smaller than the number of bits needed to encode the N numerical constants of the cryptographic algorithm, expanding (128) the seed deterministically to obtain a sequence of numbers whose size, in number of bits, is at least equal to the number of bits needed to encode the N numerical constants of the cryptographic algorithm, generating (132) N new numerical constants from the sequence of numbers obtained, and replacing (134) the N constants of the code of the cryptographic algorithm by the N new constants generated to obtain the code of a renewed cryptographic algorithm.

Description

technical field [0001] The invention relates to a password update module and update method that can be executed by an electronic computer, and also relates to a security processor and an information recording medium for executing the above method. Background technique [0002] Usually, a cryptographic algorithm is used to encrypt a segment of data D with a key K, thereby obtaining a password D * , or pass key K to cipher D * Decryption is performed to obtain segments of data D. When a cryptographic algorithm is executed on an electronic computer, such cryptographic algorithm corresponds to executable or translatable code. Here, the codes to be executed have been compiled in advance, so that the computer can directly execute these codes. And when the code is translated into instructions and executed, the code can be translated. Wherein, codes can be translated into executable instructions by means of a "virtual machine", for example, the JAVA language produced by Sun Micr...

AI Technical Summary

Problems solved by technology

Furthermore, the security processor monitors and cryptanalyzes the received startup message so that the security processor itself cannot find out the update encryption algorithm

[0012] However, the second method requires more memory resources due to the need to initialize records of the different variables of the cryptographic algorithm in the security processor

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