Tony Arcieri edited this page Dec 28, 2016 · 64 revisions

Easier-to-Use Cryptography*


Confused about cryptography? Don't know which primitive to choose? Do you have no idea what a nonce is? No worries!

SimpleBox puts cryptography on Rails. Think of it as omakase cryptography: all of the hard decisions have been made for you, providing the simplest API available while still providing the best cryptographic guarantees you are going to get out of a Ruby library, period.

Secret-key Encryption

Secret-key encryption works like a safe: you can put information inside of a "SecretBox", and anyone with the combination can open it.

Public-key Encryption

NaCl's public-key encryption works similarly to GPG: anyone can publish a public key, and if you have someone's public key, you can put messages into a "Box", but once closed, only the holder of the private key can open it.

Digital Signatures

In the real world, signatures help uniquely identify people because everyone's signature is unique. Digital signatures work similarly in that they are unique to holders of a private key, but unlike real world signatures, digital signatures are unforgeable.


HMAC provides hash-based message authentication codes, the symmetric equivalent to digital signatures. Anyone who knows a particular secret value can use that value to generate MACs or verify the authenticity of a MAC for a given message.

Hash Functions

Cryptographic hash functions compute a secure, fixed-length output from an arbitrarily long input. These functions are designed to keep the actual data being hashed confidential.

Password Hashing

Hash functions specifically designed for the purposes of deriving cryptographic keys or password storage that is resistant to brute force.

Power-User Cryptography

Scalar Multiplication

Direct access to the Curve25519 elliptic curve Diffie-Hellman function that underlies NaCl's public-key cryptography

One-time Authentication

Direct access to the Poly1305 one-time MAC function used by RbNaCl::Box and RbNaCl::SecretBox to authenticate messages

Additional Features

Random Number Generation

Create secure random numbers without screwing it up!


Miscellaneous features which can be used in conjunction with the cryptographic features:

  • Constant-time string comparison

YARD API Documentation

Secret-Key Encryption

Public-Key Encryption

Digital Signatures


Hash Functions

Password Hashing Functions

  • RbNaCl::PasswordHash: Compute hashes for passwords that are designed to be resistant to brute force attacks

Scalar Multiplication

*NOTE: crypto is really, really, really, really, really hard