sphinxcrypto 0.0.15

Sphinx cryptographic packet format library
Documentation

rust-sphinxcrypto

This crate provides a concrete parameterization of the Sphinx cryptographic packet format and follows this "Sphinx Mix Network Cryptographic Packet Format Specification" document:

https://github.com/katzenpost/docs/blob/master/specs/sphinx.rst

Sphinx has the following features:

  • Single Use Reply Blocks
  • per hop bitwise unlinkability
  • indistinguishable replies
  • hidden path length
  • hidden relay position
  • tagging attack detection
  • reply attack detection

Read the Sphinx paper, Sphinx: A Compact and Provably Secure Mix Format by George Danezis and Ian Goldberg. See https://cypherpunks.ca/~iang/pubs/Sphinx_Oakland09.pdf

warning

This code has not been formally audited by a cryptographer. It therefore should not be considered safe or correct. Use it at your own risk!

details

The currently implemented Sphinx cryptographic parameterization is:

  • EXP(X, Y) - X25519
  • MAC(K, M), H(M) - Blake2b
  • S(K, IV) - Chacha20
  • KDF(SALT, IKM) - HKDF Sha256
  • SPRP_Encrypt(K, M)/SPRP_Decrypt(K, M) - AEZ

The Sphinx packet geometry is parameterized in the constants submodule.

Usage

To import sphinxcrypto, add the following to the dependencies section of your project's Cargo.toml:

sphinxcrypto = "^0.0.15"

Then import the crate as:

extern crate sphinxcrypto;

acknowledgments

This library is a Rust language port of Yawning's Katzenpost Sphinx implementation:

https://github.com/katzenpost/core/tree/master/sphinx

Thanks to Jeff Burdges for helping me with some of my rust problems.

license

GNU AFFERO GENERAL PUBLIC LICENSE