Research on dynamic key generation and data encryption scheme based on chaotic mapping and SM4

In the field of information security, the storage of private data is always one of the key security risk points. This study aims to design and implement a dynamic key generation and data encryption scheme based on chaotic mapping and SM4 algorithm. By selecting Logistic chaotic mapping to generate pseudo-random sequences, the unpredictability of chaotic systems is used for the dynamic update of SM4 keys, thereby enhancing the security and randomness of SM4 key updates. Then, combining the encryption security of SM4 algorithm and the encryption speed advantage of chaotic sequence, data storage encryption is achieved through chaotic sequence mapping parameter initialization, chaotic sequence binary quantization, SM4 dynamic encryption and tail processing. Experimental analysis shows that the algorithm has the characteristics of large key space and good key sensitivity. While improving the encryption speed, it effectively reduces the memory usage and maintains high execution efficiency.