A Framework for Universally Composable Non-Committing Blind Signatures
Source: Nippon Telegraph and Telephone
A Universally Composable (UC) blind signature functionality requires user to commit to the message to be blindly signed. It is thereby impossible to realize in the plain model. This paper shows that even non-committing variants of UC blind signature functionality cannot be realized in the plain model. The authors characterize UC non-committing blind signatures in the common reference string model by presenting equivalent stand-alone security notions under static corruption. Usefulness of the characterization is demonstrated by showing that Fischlin's basic stand-alone blind signature scheme can be transformed into a UC non-committing blind signature protocol without using extra cryptographic components.