Abstract:

A certificateless chameleon hash function was constructed based on the certificateless cryptography. It resolves the key escrow problem in identity-based chameleon hashing perfectly. No one except the specified verifier can find a collision of our proposed chameleon hash function. Moreover, a certificateless chameleon signature was given in this paper. The designated verifier only can verify the validity of signature in the verification process of our scheme. The new scheme is simple and efficient, which is secure in the random oracle model.

Key words:  certificateless cryptography; chameleon digital signature; designated verifier