Provable security for blind signature on discrete logarithm

Provable security is a definition and reduction based approach to security analysis for cryptographic schemes and protocols which proves to be a landmark in modern cryptography. In the paper, we introduced provable security and random oracle model into the designing and analyzing of blind signature, and presented an improved blind signature with formal security analysis on discrete logarithm problem. Security analysis was made under the random oracle model to justify the unforgeability (UF-CMA) of the scheme. Furthermore, we generalized malleability of encryption into security of non-malleability for signature scheme and formally proved the non-repudiation of blind signature based on this assumption. Besides, the algorithms in the schemes can be generalized into other cryptosystems based on discrete logarithm without any influence to efficiency or security. Copyright © 2010 Binary Information Press.