An Improved Secure Identity-Based On-Line/Off-Line Signature Scheme

摘要

On-line/off-line signature is an important cryptographic tool, it is widely applied to resource-constrained environment. Recently, an ID-based online/offline signature scheme was proposed for authentication in the AODV protocol. Unfortunately, we show that the scheme are insecure in the paper, it is universally forgeable and malleable. And we give a stronger attack which is able to make that any one can produce a forged signature on arbitrary a message in the absence of the private key of a signer and a valid signature of a message. To overcome the attack, an improved scheme is proposed and we show that the improved scheme is provably secure against adaptive chosen message attack in the random oracle model.