Online and offline circulating unbalanced oil and vinegar signature method

Disclosed in the present invention is an online and offline circulating unbalanced oil and vinegar signature method. The method breaks down a traditional unbalanced oil and vinegar signature process into an offline part and an online part, wherein offline steps are independent of a signature message and may be performed in advance, and a circulating computation method is used in combination during a computing process so as to enhance performance. When a signature is needed during the online part, a computing result stored during the offline steps is used in combination for completing a final signature operation. The method provided in the present invention is a multi-variable public key system-based unbalanced oil and vinegar signature scheme which is a lightweight digital signature solution applicable to low-performance electronic equipment. In the present invention, an unbalanced oil and vinegar signature algorithm is divided into the offline part and the online part, the computation during the offline steps may be performed in advance, and the online signature process may be accelerated at the same time that energy is more fully utilized. According to the present invention, a circulating computation method is used in the computation of the offline steps, so that the size of a secret key is greatly reduced, and meanwhile, the signature period is shortened.