Method for generating key sequence and apparatus for generating cipher key

Abstract

The invention provides a generation method of a key sequence and a key generation device; wherein, the method comprises the steps: A, key seeds are obtained, divided into N sections and put into N LFSRs in the device, wherein, N is an integral number; B, constant bits are extracted from each LFSR and carried out conversion, whether the LFSR needed to be shifted is determined according to the result after conversion, and the LFSR needed to be shifted is controlled; C, one or more bits from the LFSR are extracted and processed to form an intermediate key sequence; and D, the intermediate key sequence is carried out scrambling conversion so as to form the key sequence. The method can greatly improve the nonlinearity degree of the key sequence.

Description

technical field [0001] The invention relates to the technical field of encryption and decryption, in particular to a method for generating a key sequence and a key generating device. Background technique [0002] With the rapid development of network technology, the security requirements for data content transmission between devices are getting higher and higher. The most common way is when transmitting data streams, the sender uses a key to encrypt the data streams to be transmitted. The receiving end then uses the same key to decrypt the received data stream, thereby preventing the leakage of the data stream content. [0003] The specific system structure can be as follows figure 1 As shown, the key generation module in the sending end uses the key seed to generate a key sequence, and the encryption module uses the encryption sequence to encrypt the plaintext data and then transmits the ciphertext data to the receiving end; the key generating module in the receiving end u...

AI Technical Summary

Problems solved by technology

In the encryption and decryption process, the non-linearity and autocorrelation of the key will affect the security level of the encryption and decryption. The higher the degree of nonlinearity, the higher the security level. The final output data is linear, relying entirely on the mixing processing of the mixing module to improve the non-linearity of the key sequence. Obviously, the operation of the mixing module to scramble the order according to the predetermined rules still makes the non-linearity of the key sequence very low

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