To piggy back on this thread, can anyone recommend a book on cryptography for mathematicians? I'm familiar with some of the more popular applied books, but I'm also interested in more rigorous texts that use careful proofs and state theorems etc.
We used the above two books in addition to Handbook of Applied Cryptography by Alfred J. Menezes, Paul C. van Oorschot and Scott A. Vanstone. I notice Boneh no longer uses the latter for CS255; perhaps it is too out of date now? At any rate, it is also available free on the web: https://cacr.uwaterloo.ca/hac/
Neil Koblitz has "A Course in Number Theory and Cryptography", which I haven't read, but is often used: https://www.amazon.com/Course-Number-Cryptography-Graduate-M...
Also, Boneh and Shoup is good and mentioned in other comments: https://toc.cryptobook.us/