Fault analysis attack detection method for last round reduction round of SM4 cryptographic algorithm

The invention discloses a fault analysis attack detection method for the last round reduction round of an SM4 cryptographic algorithm, and the method comprises the following steps: S1, carrying out the fault injection of the round input of the last four rounds of the SM4 cryptographic algorithm, so as to reduce the number of iterated rounds, and obtaining the round input of the last four rounds of the SM4 cryptographic algorithm; s2, round keys of the last four rounds are deduced according to round input of the last four rounds of the SM4 cryptographic algorithm, and an initial key is reversely calculated according to an SM4 key expansion algorithm; by the adoption of the analysis method, SM4 reduction round fault analysis is achieved, the number of attacks needed for attacking a complete secret key is reduced, and the attack efficiency and the success rate are improved. 本发明公开了一种针对SM4密码算法末轮约减轮故障分析攻击检测方法，包括以下步骤：S1：对SM4密码算法后4轮的轮输入进行故障注入来减少迭代的轮数，获取SM4密码算法后4轮的轮输入；S2：根据SM4密码算法后4轮的轮输入推出后4轮的轮密钥，根据SM4密钥扩展算法，逆向计算出初始密钥