Plaintext selection related collision attack method based on mask SM4 cryptographic algorithm

Abstract

The invention relates to the field of side channel attacks, and discloses a plaintext selection related collision attack method based on a mask SM4 cryptographic algorithm. The method comprises a measurement stage and a collision detection stage; in the measurement stage, an attacker performs encryption operation on cryptographic equipment by selecting an input plaintext, records and collects a corresponding energy trace for use in the collision detection stage; in the collision detection stage, the attacker performs correlation calculation according to the collected energy traces and based onthe energy traces corresponding to the two collision bytes, so that the input difference of the collision bytes is determined; four round secret keys are obtained after obtaining the input differenceamong the four bytes, namely the round secret key information of the first round; and then the attack method is repeatedly performed, and round keys of the second round, the third round and the fourth round are sequentially solved; and finally an original 128-bit key is reversely deduced through a key expansion algorithm. According to the method, the encryption frequency required by collision isreduced, and the algorithm attack on the mask SM4 is realized.

Description

technical field [0001] The invention relates to the field of side channel attacks, in particular to a selected plaintext correlation collision attack method based on a masked SM4 cipher algorithm. Background technique [0002] (1) Masking scheme based on SM4 cryptographic algorithm [0003] The SM4 cipher algorithm is a block cipher standard adopted by the Chinese government. The algorithm is a grouping algorithm with a group length of 128 bits and a key length of 128 bits. Both the encryption algorithm and the key expansion algorithm adopt a 32-round nonlinear iterative structure. The structure of the decryption algorithm is the same as that of the encryption algorithm, except that the order in which the round keys are used is reversed, and the decryption round key is the reverse order of the encryption round key. [0004] The SM4 algorithm encryption process is attached figure 1 shown. Let the plaintext input be X 0 , X 1 , X 2 , X 3 , the round key is i=0, 1, 2...

AI Technical Summary

Problems solved by technology

Collision attacks are only effective for unprotected cryptographic algorithms. When the cryptographic algorithm is added with mask protection measures, collision attacks are difficult to work

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