US 11,722,312 B2
Privacy-preserving signature
Eric Diehl, Culver City, CA (US)
Assigned to Sony Group Corporation, Tokyo (JP); and Sony Pictures Entertainment Inc., Culver City, CA (US)
Filed by Sony Group Corporation, Tokyo (JP); and Sony Pictures Entertainment Inc., Culver City, CA (US)
Filed on Mar. 9, 2020, as Appl. No. 16/813,446.
Prior Publication US 2021/0281422 A1, Sep. 9, 2021
Int. Cl. H04L 29/06 (2006.01); H04L 9/32 (2006.01); H04L 9/08 (2006.01); H04L 9/06 (2006.01)
CPC H04L 9/3247 (2013.01) [H04L 9/0662 (2013.01); H04L 9/0825 (2013.01); H04L 9/0869 (2013.01); H04L 9/0894 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A method for signing data so that a signature can be verified by a verifier while preserving the privacy of a signer, the method comprising:
generating a signature nonce by processing the data with a secret function,
wherein the secret function is a function known only to the signer and is used to generate a pseudo-random value of the signature nonce based on data to be signed;
encrypting the signature nonce by the signer with a public key of the verifier to produce an encrypted signature nonce so that the encrypted signature nonce can be decrypted with a private key of the verifier instead of a private key of the signer;
calculating a signature of the data of the signer by signing the data concatenated with the signature nonce using the private key of the signer; and
distributing the data, the encrypted signature nonce, and the signature of the data of the signer.