Partially blind signature method based on identity on lattice

Abstract

The invention relates to a partially blind signature method based on identity on a lattice. The method comprises the following steps: 1) a private key generator PKG (private key generator) generates a system main key S0 and a system parameter Param by taking a security parameter lambda as the input and using a trap-door generation algorithm TrapGen(1lambda); 2) the PKG uses the main key S0, the identity ID of a signer and the system parameter Param, and uses a matrix sampling algorithm SampleMat to output the private key SID corresponding to the ID; 3) the signer S randomly selects a vector y in the distribution as shown in description, randomly samples a vector pair as shown in description, and then computes to obtain (c1,c2) to send to a message owner C; 4) C blinds the to-be-signed message msg by using the (c1,c2) to obtain the blinded message epsilon* to send to S; 5) the S computes the signature as shown in description of the blinded message epsilon* by using the private key SID and the sampling rejection theorem to send to the C; and 6) the C makes the de-blinding computation to output the signature (z1, z2, epsilon1, epsilon2) of the message (msg, info); a verifier V can verify the accuracy of the message (msg, info) and the signature (z1, z2, epsilon1, epsilon2) through a certain computation. The attack from the quantum computer can be resisted, the generated user key is short, and the signature speed is fast.

Description

technical field [0001] The invention relates to the technical field of information security, and specifically proposes an identity-based partial blind signature method on lattice. Background technique [0002] At present, the lattice-based public-key cryptosystem is one of the few classical public-key cryptosystems that cannot be broken by quantum computers, and the lattice-based public-key cryptosystem has other excellent properties, such as the average case is as safe as the worst case and simple and efficient etc. Therefore, the lattice-based cryptosystem can become an important tool to ensure information security in the quantum era. [0003] Blind signature (BS, blind signature) is an interactive protocol between the signer and the requester, which allows the signer to sign the message without knowing the specific content of the message to be signed. When the blind signature is announced, the signer also It was not possible to link the signing process to the final publi...

AI Technical Summary

Problems solved by technology

Especially in the electronic cash system, the partial blind signature can not only protect the privacy of the signature requester but also enable the signer to partially control the content of the signature, which solves the problem of blind signature in practical applications well, and the partial blind signature It is more efficient than blind signatures in applications, but there is currently no provably secure identity-based partial blind signature scheme on lattices

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