Garbled circuit over-simplificationDue: April 19
Here is a short paper from (I think) a Ph.D. student at UC Davis describing a simplified version of Yao's garbled circuit protocol.
I thought about assigning it as a reference material for the class, and then realized there is a major, serious security flaw in how it handles the encryptions.
Here's the link: https://www.math.ucla.edu/~tdokos/notes_files/garbledCircuits.pdf
Find the security flaw and describe how it could be used for Bob (the circuit evaluator) to do something that he shouldn't be able to do.
(Note: I have tried to be responsible and asked the author to fix it or take down the PDF, and got no response. So I'm doing the next-best thing, which is to make a problem out of it for you to solve!)