Packages

bitcoinlib

0.1.0
0.4.7 0.4.6 0.4.5 0.4.4 0.4.3 0.4.2 0.4.1 0.4.0 0.3.5 0.3.4 0.3.3 0.3.2 0.3.1 0.3.0 0.2.10 0.2.9 0.2.8 0.2.7 0.2.6 0.2.5 0.2.4 0.2.3 0.2.2 0.2.0 0.2.0-pre4 0.2.0-pre3 0.2.0-pre2 0.2.0-pre1 0.1.3 0.1.2 0.1.1 0.1.0

Generate private/public keys and addresses for the bitcoin network

HexDocs

Current section

Files

Jump to
Readme
32 Versions
5 Dependencies
Dependants
Files
Activity
bitcoinlib lib crypto secp256k1.ex
Raw

lib/crypto/secp256k1.ex 

defmodule BitcoinLib.Crypto.Secp256k1 do

  @moduledoc """

  Elliptic curve cryptography



  Based on https://hexdocs.pm/curvy/Curvy.html

  """



  alias Curvy.{Point, Key}



  @doc """

  Add two keys on the elliptic curve using Jacobian Point mathematics



  ## Examples

    iex> key1 = 0x2E65A9C40338B8D07D72CD82BF3C9DDD0375F362863BC0808E6AD194F19F5EBA0

    ...> key2 = 0x2702DED1CCA9816FA1A94787FFC6F3ACE62CD3B63164F76D227D0935A33EE48C3

    ...> BitcoinLib.Crypto.Secp256k1.add_keys(key1, key2)

    0x2FC5BA55A539899D67EE66E99EE50AB59DCCBB122025D18C5EB9446D380A9EC0A

  """

  def add_keys(key1, key2) do

    point1 = get_point(key1)

    point2 = get_point(key2)



    add_points(point1, point2)

    |> to_integer()

  end



  defp get_point(key) do

    key

    |> Binary.from_integer()

    |> Key.from_pubkey()

    |> Map.get(:point)

  end



  defp add_points(point1, point2) do

    Point.add(point1, point2)

  end



  defp to_integer(point) do

    point

    |> Key.from_point()

    |> Key.to_pubkey()

    |> Binary.to_integer()

  end

end