关键词: 数字签名, 椭圆曲线, 消息恢复, 生日攻击

Abstract: The paper analyses a signature scheme with message recovery based on elliptic curves, and finds the original scheme is insecure in message recovery. An improved scheme is presented in this paper to solve the problem that anyone can restore original message. An attack, named birthday attack, to a signature scheme with message recovery based on elliptic curves is introduced. When attackers use birthday attack to attack the signature information the secret key is easily exposed in original scheme, in this regard, an improved scheme is put forward and the new scheme can fully resist birthday attack.

Key words: digital signature, elliptic curve, message recovery, birthday attack