Outline for March 15, 2006

Reading: text, §22 (except 22.6)

1. Greetings and felicitations!
2. Malicious logic
   1. Quickly review Trojan horses, viruses, bacteria; include animal and Thompson's compiler trick
   2. Logic Bombs, Worms (Schoch and Hupp)
3. Ideal: program to detect malicious logic
   1. Can be shown: not possible to be precise in most general case
   2. Can detect all such programs if willing to accept false positives
   3. Can constrain case enough to locate specific malicious logic
   4. Can use:
      1. Type checking (data vs. instructions)
      2. Limiting rights (sandboxing)
      3. Limiting sharing
      4. Preventing or detecting changes to files
      5. Prevent code from acting beyond specification (proof carrying code)
      6. Check statistical characteristics of programs (more authors than known, constructs in object files not corresponding to anything in the source)