Salty

An Elixir wrapper for enacl and libsodium.

Requirements

Installation of Salty require the following library to be installed:

• libsodium must be installed on your machine.

Installation

Add salty to your hex dependencies:

defp deps do
  [{:salty, "~> 0.1.0"}]
end

Then run mix deps.get and you're done.

Usage

Salty supports both symmetric-key encryption (SecretBox) and asymmetric-key encryption (Box) with optional integration with Cloak for use in Ecto applications.

Symmetric-key encryption

Symmetric-key encryption is an encryption that uses the same key to encrypt and decrypt the data. In this scheme, in order for Alice and Bob to send each other a message, they both will have to share the same key. No one else can decrypt the message without knowing the key.

iex> key = Salty.SecretBox.generate_key
"j6fy7rZP9ASvf1bmywWGRjrmh8gKANrg40yWZ-rSKpI"
iex> payload = Salty.SecretBox.encrypt(%{key: key, payload: "hello, world"})
"HDNg7zwwGejt9qWe8UbvQZFIMCGbO2L841Z4Pwh9Vhi-vKCCdILYlDy5RkHB"
iex> Salty.SecretBox.decrypt(%{key: key, payload: payload})
"hello, world"

Using with Cloak

Salty symmetric-key encryption can be used as a cipher for Cloak and supports key migration via multiple key tags the same way Cloak.AES.CTR does:

config :cloak, Salty.SecretBox.Cloak,
  tag: "SBX",
  default: true,
  keys: [
    %{tag: <<1>>, key: "..."},
    %{tag: <<2>>, key: "...", default: true},
  ]

Asymmetric-key encryption

Asymmetric-key encryption is an encryption that uses two different keys for each party. For Alice to send Bob a message in this scheme, the message need to be encrypted with Alice's private key and Bob's public key, and for Bob to decrypt the message, Bob will need to decrypt the message with his own private key and Alice's public key. An attacker cannot decrypt the message without first obtaining the private key of either Alice or Bob.

iex> alice_secret_key = Salty.Box.generate_secret_key
"NuPf7kaOvJrdETKI5PR7qV7KFTCzjX19QYBGTaPOAu4"
iex> alice_public_key = Salty.Box.generate_public_key(alice_secret_key)
"VU8_8ZV-njF3N7cB5YUkqWAZwRb88edvRb6J1GU230Q"
iex> bob_secret_key = Salty.Box.generate_secret_key
"FuhDx6EifCK_EudsBq1fp0RkcE2tASodXaUz85xgjoA"
iex> bob_public_key = Salty.Box.generate_public_key(bob_secret_key)
"1MV78_LqSCKetEfr9aoi0sMIXdsywfJgTyUDPPYiiRM"
iex> payload = Salty.Box.encrypt(%{
...>   secret_key: alice_secret_key,
...>   public_key: bob_public_key,
...>   payload: "hello, world"
...> })
"sigKcp3CuC3cW0Fio_MQ4SjkDH10KQh2fYVFSoouSgaOZxArzgGTUmraXxU_8gl0fjsEnA"
iex> Salty.Box.decrypt(%{
...>   secret_key: bob_secret_key,
...>   public_key: alice_public_key,
...>   payload: payload
...> })
"hello, world"

Using with Cloak

Salty asymmetric-key encryption can be used as a cipher for Cloak and supports key migration via multiple key tags the same way Cloak.AES.CTR does:

config :cloak, Salty.Box.Cloak,
  tag: "BOX",
  default: true,
  keys: [
    %{tag: <<1>>, public_key: "...", secret_key: "..."},
    %{tag: <<2>>, public_key: "...", secret_key: "...", default: true},
  ]

Contributing

See how you can help.

License

Salty is released under the Apache License.