CS338 Computer Security
Wednesday, 12 November 2025

+ Exam 1 corrections
- "validation" of signatures

    given a document D and a signature Sig
     purportedly created by Bob, check whether
     the signature is correct using Bob's P_B
        e.g. E(P_B, Sig) ==? H(D)

- "validation" of certificates

    given certificate C which includes signature
        Sig, purportedly created by certificate
        authority CA, validate the signature
        (using P_CA). If CA is not a root level
        authority, then you have to validate
        *its* certificate, etc. until you get to the root.

+ Exam 2, part 1 is posted
- I have to fix cs338.jeffondich.com/fdf/, so give me a couple hours
- Same with clear LLM instructions: I'll get you those today

+ Projects
- I'll let you share on Slack (points TBD)

+ ??

+ Prep for ARP poisoning lab Friday
- Do a little Wireshark sniffing and look at a whole frame. What's in there?
- MAC addresses
- Network interfaces
- Routing tables
- ARP