摘要： 基于当前网络通信中对报文鉴别码(MAC)的需求，介绍了Hash函数在密码学上的安全性质，分析了Hash函数在报文鉴别中的应用和针对Hash函数的主要攻击。在此基础之上，提出一种基于Hash函数的报文鉴别码——伪报文鉴别码(PMAC)。利用当前现有的Hash函数来构造MAC，而不改变原有的Hash函数的内部结构。在没有利用任何现有加密算法的基础上，仅应用一个密钥不仅对报文提供了鉴别，而且也提供了机密性。对该伪报文鉴别算法的安全性进行了初步分析。

关键词: Hash函数, 报文鉴别码, 伪报文鉴别码

Abstract: Based on the requirements of message authentication code (MAC) in current network communication, this paper introduces the cryptographic secure properties of a Hash function, and analyses its applications in message authentication and the main attacks against a Hash function. It presents a new message authentication method based on a hash function, the pseudo-message authentication code (PMAC). The proposed method constructs a MAC by an existing Hash function, and doesn’t change the inner structure of this Hash function. The proposed method, which doesn’t apply any existing encryption arithmetic, can provide message confidentiality as well as authentication by only a secret key. This paper gives a basic security analysis of PMAC.

Key words: Hash function, Message authentication code, Pseudo-message authentication code

中图分类号: 

• TP393