CS 685 Computer Security

Quick Facts

Times: Monday and Wednesday: 19:05 - 20:25
Location: Technology Hall N324
Instructor: Dr. Delbert R. Hart
Office: Technology Hall N345
email: dhart@cs.uah.edu
Phone: (256) 824-5160 (email preferred)
Required Textbook:
Title Computer Security
Author Dieter Gollmann
Publisher John Wiley & Sons
ISBN 0-471-97844-2

Optional Textbook:
Title Practical Unix and Internet Security
Author Simson Garfinkel and Gene Spafford
Publisher O'Reilly
ISBN 1-56592-148-8

Final Exam: Mon Dec 10 18:30 - 21:00

Basic Information


This class will cover the basic theoretical and practical aspects of computer security. Students are required to follow all applicable acceptable use and other computer policies. Failure to do so will result in failing grade for the course in addition to other penalties.

Exams

Test 1 ps
Test 1 pdf

Test 2 ps
Test 2 pdf

Test 3 ps
Test 3 pdf

Test 4 ps
Test 4 pdf

Resources

Class info pdf ps Local CVS information here
AREN Acceptable Use Policy
UAH Acceptable Use Policy

Homework

  1. August 30, 2001

    Inspect the security settings of the programs you typically use: (email, web browser, etc). Ask yourself why you need each feature that is enabled and what threat it poses.
    Locate software that will enable you to sign/encrypt your email.
    Download a password cracking program and evaluate the strength of the passwords that you use.
    From the textbook: 2.2, 2.3, 2.7, 3.3, 3.4, 3.7

  2. September 24, 2001

    There have been recent calls to backdoors to encryption products. Estimate the practical viability of such an approach. Specifically devise a feasible scheme of who would keep the keys and how they would be used. Then estimate the (monetary) value of the keys and determine what safeguards would be necessary to protect them.
    Another recent event has been another worm, Nimba. Find an official warning about the worm on the internet. Decide what vulnerabilities it exploited and how similar attacks could be avoided in the future. What are the obstacles?
    From the book, Chapter 4: 4.1, a paragraph or two on 4.2, 4.3, 4.5, 4.10
    As part of 4.10 consider scenarios for each of the models. What strengths and weaknesses does each model have?
    What are the purpose of models? What do they provide that you wouldn't have by just coding them?

  3. October 3, 2001

    Questions from the book: 5.2, 5.3, 5.6, 5.7, and 5.9 with the addition that you consider what (if any) security implications this has.
    6.1, 6.2, and a couple of paragraphs on 6.8
    How are the reference monitor, security kernel, and trusted computing base related to each other?
    Interrupts allow a processor to respond to actions in the outside world. Another way of responding is to use polling. Consider the pros and cons in general and with respect to security of interrupts versus polling.
    Describe real user id versus effective user id. Is it worthwhile to distinguish between the two? Come up with an example to illustrate its usefulness.
    A very careful system administrator may install new software while operating under a chrooted environment. What are the pros and cons of this approach.
    How can you implement an ACL using setuid programs? What is the trade-off between a setuid implementation and a kernel implementation?

  4. October 23, 2001

    From the book questions 7.3, 7.6, 8.3, 8.5, 8.6, 8.7, 9.3, 9.7.
    
    What are the trade-offs of evaluating the process versus evaluating the
    product.
    
    Is it better to emphasize prevention or monitoring?  Explain.
    
    What is the least privilege principle?  Give an example of how it would be
    violated.
    
    Describe an interrupt table virus.
    
    What are viruses, worms, and trojan horses?
    
    Find the source code for one of the above and review how it worked and
    propagated.  What security hole did it exploit?
    
    Download a virus scanner and see if you find anything.  Consider what you
    need to do to be sure that a virus can't interfere with the scan.
    
    Look at all of the processes currently running, do you know what each of
    them does?
    
  5. November 12, 2001

    
    From the book: 10.1, 10.4, 10.5, 10.7, 11.6, 11.7.
    
    What ideas is the Kerberos protocol based on?  What are the
    strengths and weaknesses of these ideas?
    
    Find another security protocol for distributed systems and
    compare it to Kerberos.
    
    What are the pros and cons of cookies?  Propose an alternative.
    
    Consider the trade-offs between conveinence and security in
    web browsing.
    
  6. November 26, 2001 (a)
    From the book 12.1, 12.2, 12.3, 12.10, 13.5, 13.7, 13.8, 14.3 and 14.5.
    
    How does a digital signature differ from an encrypted message?
    
    What are IPSec and SSL?
    
    What are the different types of network security protections
    available?  What are the strengths of each?
    
    How are views useful for security?
    
    
  7. November 26, 2001 (b)
    From the book 17.5, and 17.6.
    
    Discuss what goes into an acceptable use policy.
    
    Describe the DES algorithm.
    

dhart@cs.uah.edu
Last modified: Tue Nov 20 13:02:47 CST 2001