Obfuscation

Python is the best language to start with if you are a beginner, which is what makes it so popular. You can write powerful code with just a few lines, and most importantly, you can handle arbitrarily large integers with complete precision. This book covers essential cryptography concepts; classic encryption methods, such as the Caesar cipher and XOR; the concepts of confusion and diffusion, which determine how strong a crypto system is; hiding data with obfuscation; hashing data for integrity and passwords; and strong encryption methods and attacks against these methods, including the padding oracle attack. You do not need to have programming experience to learn any of this. You don't need any special computer; any computer that can run Python can do these projects. We'll not be inventing new encryption techniques just for learning how to use standard pre-existing ones that don't require anything more than very basic algebra.

We will first deal with obfuscation, the basic idea of what encryption is, and old-fashioned encryption techniques that hide data to make it more difficult to read. This latter process is one of the basic activities that encryption modules use in combination with other methods to make stronger, more modern encryption techniques.

In this chapter, we will cover the following topics:

• About cryptography
• Installing and setting up Python
• Caesar cipher and ROT13
• base64 encoding
• XOR