Study on the efficiency and fault tolerance of block cipher algorithm based on energy analysis

Block cipher is one of the most widely used cryptographic systems. It is a kind of symmetric cipher algorithm, which uses the same key for encryption and decryption. In essence, the block cipher is a permutation with a key, which divides the data into groups with equal length and is converted to the same length. At present, the main block cipher algorithm has high security, it is difficult to be mathematically analyzed. However, the mathematical analysis method is mainly aimed at the analysis of the text and the cipher text, and has some limitations in the security analysis of the encryption device. Since (1) is proposed to study the operating time of timing attacks since, side channel attack and defense has gradually become the cryptography is one of the important branches. Unlike the traditional brute force crack, or the account of the weakness of the password theory, the side channel attack analysis of the password algorithm to the physical realization of the process of certain intermediate values of the leakage of information, thus obtaining the key. Time, electromagnetic wave, and even sound can be used as the side channel information of the attack code system. In addition, the energy consumption analysis is one of the most effective means of side channel attack.Attackers usually want to attack as fast and efficient as possible, we use this as the starting point to propose a more flexible based on the two step distance of the bit collision attack, which uses the energy track distance model and the idea of a bit by bit. Take the algorithm as an example, select a full zero express and a special expressly factory each strictly contains a wide range of the same byte, the second is, the other bits are. And key of XOR box input values were obtained, each box of the input value is the change of key bytes of the bit and the Hamming weight before and after the operation also change. Due to input the corpse does not cause any bit change and therefore input tightly, through the comparison of different box input value of Hamming weight difference whether and input the same, you can infer the corresponding key bytes of the bit is equal.Therefore, under the different energy analysis, the different structures of the box of the anti attack. The design of the algorithm can be considered in the case of different attack method in the case of the security strength to meet specific needs.