Practical Cryptography for Developers (in Ruby)

This repository contains examples of how to use various Ruby libraries to perform cryptographic operations safely and with purpose.

The primary purposes of cryptography are:

• Confidentiality
• Integrity
• Non-repudiation
• Authentication

The examples in this repository depend on the https://github.com/RubyCrypto/rbnacl gem and the libsodium C library.

Examples

To install dependencies, run make

Confidentiality

Symmetric examples: encrypt.rb & decrypt.rb

Asymmetric examples: pkencrypt.rb & pkdecrypt.rb

Run either encrypt.rb or pkencrypt.rb with the appropriate arguments and the final output should show the command required to decrypt.

Integrity

Hash example: hash.rb

Run hash.rb with the same input argument and you should get the same output argument every time.

Asymmetric example: pksign.rb & pkverify.rb

Run pksign with the appropriate arguments and the final output should show the command required to verify.

Non-repudiation

Asymmetric examples: pksign.rb & pkverify.rb

Run pksign with the appropriate arguments and the final output should show the command required to verify.

Authentication

Symmetric example: auth.rb & verify.rb

Run auth.rb with the appropriate arguments and the final output should show the command required to verify.