Practical Cryptography in Python: Learning Correct Cryptography by Example

© Seth James Nielson, Christopher K. Monson 2019

S. J. Nielson, C. K. MonsonPractical Cryptography in Pythonhttps://doi.org/10.1007/978-1-4842-4900-0_7

7. More Symmetric Crypto: Authenticated Encryption and Kerberos

Seth James Nielson¹  and Christopher K. Monson²

(1)

Austin, TX, USA

(2)

Hampstead, MD, USA

 

In this chapter we’ll be covering some advanced symmetric cryptography, and we’ll get deeper into authenticated encryption.

Let’s dive right into an example and some code using AES-GCM.

AES-GCM

Alice and Bob have had a few close calls with Eve over the past month. During that time, they have been exchanging USB drives with encrypted files. This has worked out for them so far, but they seem to have trouble remembering a handful of key things: that they ...