[![Build Status](https://travis-ci.org/jedisct1/libhydrogen.svg?branch=master)](https://travis-ci.org/jedisct1/libhydrogen?branch=master) [![Financial Contributors on Open Collective](https://opencollective.com/libhydrogen/all/badge.svg?label=financial+contributors)](https://opencollective.com/libhydrogen) [![Coverity Scan Build Status](https://scan.coverity.com/projects/13315/badge.svg)](https://scan.coverity.com/projects/13315) ![libhydrogen](https://raw.github.com/jedisct1/libhydrogen/master/logo.png) ============== The Hydrogen library is a small, easy-to-use, hard-to-misuse cryptographic library. Features: - Consistent high-level API, inspired by libsodium. Instead of low-level primitives, it exposes simple functions to solve common problems that cryptography can solve. - 100% built using just two cryptographic building blocks: the [Curve25519](https://cr.yp.to/ecdh.html) elliptic curve, and the [Gimli](https://csrc.nist.gov/CSRC/media/Projects/Lightweight-Cryptography/documents/round-1/spec-doc/gimli-spec.pdf) permutation. - Small and easy to audit. Implemented as one tiny file for every set of operation, and adding a single `.c` file to your project is all it takes to use libhydrogen in your project. - The whole code is released under a single, very liberal license (ISC). - Zero dynamic memory allocations and low stack requirements (median: 32 bytes, max: 128 bytes). This makes it usable in constrained environments such as microcontrollers. - Portable: written in standard C99. Supports Linux, *BSD, MacOS, Windows, and the Arduino IDE out of the box. - Can generate cryptographically-secure random numbers, even on Arduino boards. - Attempts to mitigate the implications of accidental misuse, even on systems with an unreliable PRG and/or no clock. Non-goals: - Having multiple primitives serving the same purpose, even to provide compatibility with other libraries. - Networking -- but a simple key exchange API based on the Noise protocol is available, and a STROBE-based transport API will be implemented. - Interoperability with other libraries. - Replacing libsodium. Libhydrogen tries to keep the number of APIs and the code size down to a minimum. # [Libhydrogen documentation](https://github.com/jedisct1/libhydrogen/wiki) The documentation is maintained in the [libhydrogen wiki](https://github.com/jedisct1/libhydrogen/wiki). The legacy libhydrogen code (leveraging XChaCha20, SipHashX, BLAKE2SX, Curve25519) remains available in the [v0 branch](https://github.com/jedisct1/libhydrogen/tree/v0). ## Contributors ### Code Contributors This project exists thanks to all the people who contribute. [[Contribute](CONTRIBUTING.md)].