# Argon2

Argon2 password hashing for Elixir.

[Argon2](https://github.com/P-H-C/phc-winner-argon2) is the official winner of the
Password Hashing Competition, a several year project to identify a successor to
bcrypt / PBKDF2 / scrypt password hashing methods.

So far, this has only been tested on Linux. If you have any difficulties installing
or using it on your platform, please open an issue.

## Requirements

* Elixir version 1.3 or later
* Erlang / OTP version 18 or later
  * Erlang needs to be built with the `--enable-dirty-schedulers` flag set
* A C compiler, such as gcc

### Dirty scheduler

As stated above, you need to build Erlang with dirty scheduler support
to use this library, which relies on dirty scheduler support in order
to handle long-running cryptography jobs, by moving them off the main
Erlang scheduler and letting the dirty schedulers handle the work.
This keeps the Erlang VM responsive.

## Installation

  1. Add `argon2_elixir` to your list of dependencies in `mix.exs`:

    ```elixir
    def deps do
      [{:argon2_elixir, "~> 0.10"}]
    end
    ```

  2. Ensure `argon2_elixir` is started before your application:

    ```elixir
    def application do
      [applications: [:argon2_elixir]]
    end
    ```

## Use

Most users will just need to use the `hash_pwd_salt/2` and `verify_hash/3`
functions in the Argon2 module.

`hash_pwd_salt` generates a random salt and creates a hash from a password.

`verify_hash` takes a stored hash and a password and checks that the hash
is correct.

Please read the documentation for the Argon2 module for more information.

### License

Apache 2.0