Opal

A PGP encryption and decryption library via NIF bindings in sequoia

Time Limit

I initially started building something completely different, however towards the end of the hackathon I decided to try to build this instead, as I got stuck coming up with a good idea for the initial LiveView esque project.

Usecase/Example

In order to create secure financial systems, it is recommended data at rest is encrypted with AES, which is provided by the excellent erlang crypto stdlib.

For data travelling over a network, PGP is preffered. This library tries to provide a simple api library for this.

For example from Circle's documentation:

import { createMessage, encrypt, readKey } from 'openpgp'

// Object to be encrypted
interface CardDetails {
 number?: string,    // required when storing card details
 cvv?: string        // required when cardVerification is set to cvv
}

// Encrypted result
interface EncryptedValue {
 encryptedData: string,
 keyId: string
}
 
const pciEncryptionKey = await getPCIPublicKey()
 
/**
* Encrypt card data function
*/
return async function(dataToEncrypt: CardDetails): Promise<EncryptedValue> {
 const decodedPublicKey = await readKey({ armoredKey: atob(publicKey) })
  const message = await createMessage({ text: JSON.stringify(dataToEncrypt) })
  return encrypt({
    message,
    encryptionKeys: decodedPublicKey,
  }).then((ciphertext) => {
    return {
      encryptedMessage: btoa(ciphertext),
      keyId,
    }
  })
}

might be achieved in elixir like so:

with {:ok, %Key{public_key: key}} <- Opal.get_pci_public_key(), 
     {:ok, json_data} <- Jason.encode(%{hello: "world"}),
     {:ok, message} <- Opal.create_message(json_data),
     {:ok, data} <- Opal.encrypt(key, message) do
       data
     else
     # error handing
     end

Installation

If available in Hex, the package can be installed by adding opal to your list of dependencies in mix.exs:

def deps do
  [
    {:opal, "~> 0.1.0"}
  ]
end

Documentation can be generated with ExDoc and published on HexDocs. Once published, the docs can be found at https://hexdocs.pm/opal.