文档介绍：河北大学
硕士学位论文
基于化简行为轨迹的软件可信性评价模型
姓名:韩金娥
申请学位级别:硕士
专业:计算机系统结构
指导教师:田俊峰
2011-06
摘要
摘要
随着信息技术与产业的高速发展,危害信息安全的事件经常发生,可信计算技术应
运而生。目前可信计算技术对于计算机的可信测量大多仅限于系统开机时对系统资源的
静态可信性验证,但并不能保证系统运行过程中的动态可信性,因此软件的可信性评价
技术成为可信计算研究的一个重点问题。保证软件的动态可信性即是确保软件行为总是
以预期的方式达到预期的目标,故而可以通过软件行为对软件的动态可信性进行评价。
伴随着数据流攻击(如模拟攻击等)的出现,软件行为模型不仅包括软件执行的操作序
列,还要包括软件运行对应的场景信息才能充分检测出大多数攻击。
在充分考虑了软件的运行流程和运行背景的基础上,提出了基于化简行为轨迹的软
件可信性评价模型(creditability evaluation model of software based on simplified behavior
trace,简称 CEMSBT)。该模型引入行为轨迹描述软件行为,行为轨迹由运行轨迹和功
能轨迹构成,运行轨迹表示软件运行时的有序操作,表征为有序的检查点向量;功能轨
迹则由能够表征软件功能的一系列场景来刻画。为了减少可信性评价的时间和空间开
销,给出了行为轨迹的化简规则。模型应用检查点的标识评价规则和场景评价规则对实
际的软件行为进行评价。考虑到分支给程序带来的随机性很可能被入侵者利用,分支处
的检查很必要,模型通过场景确定分支的走向,从而提高评价的精确性。仿真实验表明
CEMSBT 具有较高的精确性、效率和检测能力。
关键词可信性评价软件行为行为轨迹检查点场景化简
I
Abstract
Abstract
With the rapid development of information technology and information industry, the
incidents harming information security often happen, and puting emerged as the
times require. Though technical route of TCG is able to insure the static credibility of
computer at initialization phase, it may cause security risks without considering the dynamic
credibility problem in the course of software running. So the dynamic credibility evaluation of
software has e a hot issue in information security field. Ensuring the dynamic
credibility is to keep that the software always behaves in the expected way and realizes the
expected purpose. Therefore, it is meaningful to research credibility evaluation based on
software behavior. With the emergence of mimicry attack, software behavior model should
not only contain operation sequences, but also record sequences of the corresponding scenes,
and then it can detect most of the attacks.
In order to improve the accuracy of evaluation, a creditability evaluation model of
software based on simplified behavior trace (CEMSBT) is demonstrated in this paper. We
introduce behavior trace (BT) to describe t