These resources may help you with the problem sets.
Problem 1-2 data files are available as a ZIP file or tar.bz2
archive. You might find the xor
function in encrypt.py
useful if you're writing in Python.
Problem 2-1 data files and our RC4 implementation are available as a ZIP file or tar.gz archive (both 13M compressed, 20M uncompressed).
Problem 2-2's website is at 6.857.scripts.mit.edu/ps2/. There's a Python module for accessing the website that you might find helpful, although it's a simple HTTP-based protocol. (There's also a version for Python 3, provided by student Matthew Falk — thanks!)