Two-party collaborative SM2 key generation and ciphertext decryption method and medium

Abstract

The invention relates to a two-party collaborative SM2 key generation and ciphertext decryption method and a medium, and the method is realized through the following technical scheme: t participants participating in an algorithm randomly select xi from a set {1,..., n}, and generate a verification public key Q of an SM2 ciphertext through interaction, wherein one participant U2 calculates a part of ciphertext C'1 and sends the ciphertext C' 1 to U1, and U1 finally calculates a final plaintext M'. The method has the advantages of being low in implementation complexity, high in safety, easy to verify and the like. The method is used for cooperatively decrypting the SM2 ciphertext by two parties under the condition that respective partial private keys are not leaked, the two parties need to participate in the decryption process at the same time, and the original decryption private key cannot be leaked in the SM2 ciphertext decryption process, so that the security of the private key is ensured, and the fairness of decrypting the SM2 ciphertext by the two parties is improved.

Description

technical field [0001] The invention relates to an SM2 key generation and ciphertext decryption method and medium, in particular to a two-party cooperative SM2 key generation and ciphertext decryption method and medium. Background technique [0002] With the rapid development of science and technology, platforms such as cloud computing and fog computing provide a strong support platform for data storage and transmission, and provide more convenience for people's daily life. The new architecture has brought new challenges to data integrity, confidentiality, and availability, and data security and privacy issues have become highly concerned issues. [0003] For this kind of problem, the more common solution is to divide the private key into multiple shares and send them to multiple participants. When the private key needs to be used for decryption, t divided key shares can restore the user's original private key , if less than t participants, the original private key cannot b...

AI Technical Summary

Problems solved by technology

The method and system for the two parties to cooperate to decrypt the SM2 ciphertext proposed in this patent can only be decrypted under the joint operation of the two parties, and neither party can obtain the original decryption private key

[0006] At present, the existing common key splitting or threshold secret splitting can split the key, but in the decryption stage, the key will be restored and controlled by a certain party, which reduces the security and fairness of multi-party decryption. The party who holds the complete private key can complete the decryption without the knowledge of other users

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