Research
（Japanese Version is here.）
Operating System Security
[Abstract]
Since computer networks are growing rapidly, networked computers today are at higher risk of attack through network. For example, a malicious person may hack web pages or release computer worms which perform undesirable activities on victim machines. To minimize damage from these attacks, we need operating system-level security. Security-Enhanced Linux (SELinux) is a Linux-based operating system developed by National Security Agency (NSA). While most operating systems today support discretionary access control (DAC), SELinux also supports mandatory access control (MAC) in order to improve the security. However, the configuration of SELinux access control becomes very complex. Such complexity may cause misconfiguring and spoiling the strong access control.
To reduce this complexity, a configuration tool called SELinux Policy Editor is developed by Hitachi Software. As a part of its support of configuration, this tool simplifies the configuration of SELinux by integrating some configuration items used in the SELinux access control policy. We examine effects of the simplification on the security.
[Graduation Thesis]
Abstract
Damages from computer viruses or modifications of web pages are serious problems in the Internet today. In order to prevent such damages, operating systems with security functions are actively developed.
Security-Enhanced Linux (SELinux) is the secure operating system developed by National Security Agency (NSA) . SELinux implements strong and fine-grained access control. However, the configuration of SELinux access control policy is very complex. Therefore, some tools for supporting the configuration are developed. SELinux Policy Editor is one of such tools and it simplifies the configuration by integrating some configuration items.
This paper points out extra authority given from the integration and analyses the security of SELinux access control mechanism based on the simplified policy. This analysis shows that the simplified policy may allow an attacker to steal or modify particular files illegally, and so on. Then, this paper examines improvement of the way of integration which solves the problems. Moreover, in order to make the configuration flexible for various requirements for security and configuration cost, this paper shows a way of configuration which combines the simplified configuration with the unsimplified one.
[Papers]
Katsuya SUEYASU, Toshihiro TABATA, Kouichi SAKURAI,
"On the Security of SELinux Access Control Based on a Simplified Policy,"
Proc. of the Computer Security Symposium 2003 (CSS2003), pp.253-258, Oct. 2003. (in Japanese)
Katsuya SUEYASU, Toshihiro TABATA, Kouichi SAKURAI,
"On the Security of SELinux with a Simplified Policy,"
Proc. of the IASTED International Conference on Communication, Network, and Information Security (CNIS 2003), pp.79-84, Dec. 2003.
Katsuya SUEYASU, Toshihiro TABATA, Kouichi SAKURAI,
"Notes on Secure Integration of SELinux Access Control Configuration Items,"
Proc. of the Symposium on Cryptography and Information Security (SCIS2003), pp.287-292, Jan. 2003. [PDF] (in Japanese)
[Links]
・SELinux
NSA（National Security Agency）
・SELinux Policy Editor
Hitachi Software
Return
Go To TCSLAB
Go To
SAKURAI Laboratory
Go To
SAKURAI Laboratory (Korean Version)