SM2 digital signature method based on two-party collaboration

Abstract

The invention discloses an SM2 digital signature method based on two-party collaboration, which is specifically as follows: two parties participating in the signature respectively generate respectivepublic-private key pairs (dA, PA), (dB, PB) and signature verification public keys PAB; and during the signature, A and B negotiate a session key sk at first. Then, A and B respectively select randomnumbers kA belongs to Zn, kB belongs to Zn, calculate RA=[kA]G and RB=[kB]G, and encrypts the RA=[kA]G and RB=[kB]G by using the session key and sends the RA=[kA]G and RB=[kB]G to the opposite party.At last, the A calculates a partial signature; the B calculates a partial signature and sends the partial signature to the A in the form of a ciphertext. The SM2 digital signature method disclosed bythe invention is applicable to the two parties to compete the SM2 cooperative signature together without leaking the respective partial signatures, the two parties must participate in the signature generation process at the same time, and no complete signature key is restored in the signature generation process, thereby ensuring the security of the signature key and improving the fairness of the two parties to participate in the signature.

Description

technical field [0001] The invention relates to information security technology, in particular to an SM2 digital signature method based on cooperation between two parties. Background technique [0002] Digital signature is the simulation of traditional handwritten signature in the digital environment, which can provide the unforgeability, authenticity and integrity of digital information. Typically, one party generates a digital signature that can be publicly verified by other parties. With the development of the Internet, digital signature technology has been used in many fields such as finance, commerce, military affairs and diplomacy. In order to reduce the risks caused by the concentration of signing rights or the loss of signing keys, some special documents, such as highly confidential documents, usually require the cooperation of multiple people to complete the signing. [0003] A common solution to this kind of problem is to use a threshold secret sharing scheme. I...

AI Technical Summary

Problems solved by technology

However, after recovering the complete signature key, the party holding the complete signature key can sign independently without the knowledge of other parties, thus undermining the security and fairness of the system

Especially in the case of only two parties, if one party restores and holds the complete signature key, it can sign independently without the knowledge of the other party, causing loss of benefits to the system

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