jan31 - CS 426 class...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
CS 426 class Jan 31, 2012 www.cs.purdue.edu/homes/ssw/cs426/{index.html,syll.pdf,outline} (General purpose) Operating System security Access protection of general objects In multiprogramming, OS must protect: memory (already discussed: fence, B/B, page, seg) files or data on auxiliary storage a running program in memory a directory of files a hardware device a data structure, such as a stack OS tables (page, segm) instructions, especially privileged ones passwords and user authentication mechanism the protection mechanism itself Memory protection is simple because every access goes thru certain points in hardware Other objects: more points, more paths, hard to check all A "user" or "subject" accesses an "object" Goals in protecting objects: 1. check every access (right may have been revoked) 2. enforce "least privilege" (no extra rights - pgm can't see real address) guards against part of protection mechanism failing. 3.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/23/2012 for the course CS 426 taught by Professor Staff during the Spring '08 term at Purdue.

Page1 / 2

jan31 - CS 426 class...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online