Efficient Two-Move Blind Signatures in the Common Reference String Model

Blind signatures provide a mechanism for achieving privacy and anonymity whereby a user gets the signer to sign a message of his choice without the signer learning the content of the message, nor linking message/signature request pairs when he sees the final signature. In this paper, the authors construct a blind signature that requires minimal interaction (two rounds) between the user and the signer. The signature request protocol is akin to the classic, blind-unblind methodology used for RSA blind signatures in the random oracle model.