基于加密解密过程的信息流模型(哈尔滨工业大学学报稿).doc

基于加密解密过程的信息流模型 刘益和 1 、 2 沈昌祥3 （1 、内江师范学院计算机与信息科学系 四川内江 641112 , 2、四川大学信息安全研究所 四川成都 610064, 3 海军计算技术研究所北京 100841 ） 摘要：加密解密是确保信息安全的必不可少的手段，一个安全的加密算法，可以使秘密信息加密后放在任意环境下传输，而不会泄密。从安全等级来看，加密前的信息密级高于加密后的信息密级；从信息流角度来看，信息能从高密级流向低密级。显然，如果利用客体密级来划分安全类，定义信息流策略，将不能正确地描述信息从加密到解密这一系列过程。本文通过引入客体的加密标识的概念，并利用客体的密级和完整性等级来定义新的客体安全类和信息流策略，由此得到一个新的基于加密解密过程的信息流模型。通过分析,我们认为：新模型是合理的、安全的,这将对信息安全体系结构模型构建起到积极作用。 关键词：加密解密, BLP 模型,Biba 模型,信息流模型 中图分类号： TP309 A Information Flow Model Based On Encryption And Decryption Process LIU yi-he1,2 SHEN chang-xiang3 (1.Department of Computer and Information Science,Neijiang Teachers College, Neijiang 641112 2.Institute of Information Security , Sichuan University ,Chengdu 610064 3.Computing Technology Research Institute of Navy ,Beijing 100841） Abstract: Encryption and decryption are the essential means to ensure information security, and a secure encryption algorithm can make some secret information transfer under arbitrarily the environment and cant divulge a secret when the information are encrypted. From the angle of security grade , the classification of information before which are encrypted is high to the classification of information which have encrypted , and from the angle of information flow ,the information will flow from high to low. To define the information security class and the information flow policy with the object classification, it can’ t correctly describe the encryption and decryption process by all appearances. A new information flow model based on encryption and decryption is given out in the paper, according to new information security class and new information flow policy with new concept of object’s Encryption_Mark, and with the classification and integrality grade of object .The new model is reasonable and secure by analysis, and it will rise the positive effect to design information security architecture model. Keywords: Encryption and decryption, BLP model, Biba model, Information flow model 1引言 信息安全是指必威体育官网网址性、完整性和可用性的结