一个灵活的操作系统安全框架FMAC

FMAC:A Flexible Security Framework for Secure OS

当前,操作系统的安全需求越来越多样、灵活和具体,它们往往只描述系统中一小部分实体之间的约束,但对安全策略的灵活性及定制的简洁性有较高的要求。传统的安全框架,如 FLASK 等,难于满足此类“轻量级”的安全需求。本文提出的 FMAC 框架专门面向此类安全需求,它定义了基于标记迁移系统 LTS 的安全策略模型,以规范和简化安全策略的定制。FMAC 框架由通用的对象管理器模型和安全策略管理器模型组成。讨论了 FMAC 在 Unix 类操作系统中的实现,通过层次式的客体组织与基于角色的主体组织,普通用户可以方便快捷地定制出满足要求的轻量级安全策略。

The security requirements of current operating system become more and more diverse, flexible and concrete. Usually, they only specify the constraints among a little set of entities of the system, but expect to be implemented quickly and expediently. These ＂lightweight＂ security requirements can＇t be satisfied well in traditional security framework like FLASK and this is why FMAC is presented. The FMAC model is made up of two sub-models named object manager and security policy manager. FMAC also defines a security policy model based on labeled transition system （I.TS）in order to standardize and facilitate the policy customization. How to implement FMAC in Unix-class operating systems is also discussed. It＇s simple to customize the lightweight security policies with the hierarchical structure of objects and role based structure of subjects which are two key elements of the implementation.