关键词: 签密, 可公开验证性, 密钥交换协议, 遗嘱协议

Abstract: Signcryption is a cryptographic primitive that aims at providing confidentiality and authentication simultaneously.While most previous signcryptions only provide the confidentiality and don’t provide the publicly delegated authenticity，it is promptly to be resolved problem.Using key exchange protocol and HK signature，a publicly verifiable and directed signcryption scheme is proposed.In the scheme，the sender，via the signer，generates valid signcryption text of a gain message.The proposed scheme is publicly verifiable，namely，third partity can verify signature of message.

Key words: signcryption, public verifiability, key exchange protocol, testament protocol