2 results about "Blind signature" patented technology

The application relates to the technical field of anonymous communication and provides an anonymous communication method and system based on blind signature and a medium, the method comprising the following steps: a sender generates a blind signature request containing public metadata and a message token, sends the blind signature request to a signature server, and the signature server performs blind signature; the sender performs de-blinding on the received blind signature result, obtains an anonymous token, and sends an authorization request to a bulletin board server; the bulletin board server verifies the validity of the anonymous token, allocates a mailbox and a corresponding writing time window to the sender; the sender obtains the writing permission of the mailbox within the time window, and then delivers a ciphertext to the mailbox; a receiver sends a private information retrieval request to the bulletin board server based on the mailbox identifier informed by the sender, and receives returned response ciphertext; and the receiver uses a PIR private key and a session key to decrypt the response ciphertext, and obtains a plaintext message. The application guarantees the strong privacy of both communication parties and realizes the safe transmission of confidential messages.

The present application relates to the technical field of identity authentication, and relates to a traceable blind signature data protection system based on SM9. A server initializes data protection parameters and discloses them. The server determines a private key of a first terminal and a data tracking label according to the data protection parameters, and sends them to the first terminal. The first terminal blinds transaction data according to the data protection parameters, the private key of the first terminal and the data tracking label, and determines blinded data. The blinded data is blindly signed through an SM9 algorithm. A deblinding key of the blindly signed blinded data is generated. The blindly signed blinded data is sent to the server. A second terminal purchases the blinded data through the server. The second terminal sends a decryption request and a purchase voucher to the first terminal and receives the deblinding key sent by the first terminal. The blindly signed blinded data is recovered according to the deblinding key. It can be ensured that the server and the second terminal cannot know the original data content before obtaining the deblinding key.