View Source Tezex.Crypto.ECDSA (tezex v2.0.0)

Elliptic Curve Digital Signature Algorithm (ECDSA) implementation to:

  • decode compressed public key
  • verify signatures
  • sign bytes

Summary

Functions

decode_point(compressed_pubkey, curve)
decode_public_key(compressed_pubkey, curve_name)

Decodes a compressed public key to the EC public key it is representing on EC curve.

sign(message, private_key, options \\ [])
verify?(message, signature, public_key, options \\ [])

Verifies a message signature based on a public key

Functions

Link to this function

decode_point(compressed_pubkey, curve)

View Source 
@spec decode_point(nonempty_binary(), Tezex.Crypto.Curve.t()) ::
  Tezex.Crypto.Point.t()
Link to this function

decode_public_key(compressed_pubkey, curve_name)

View Source 
@spec decode_public_key(
  nonempty_binary(),
  :prime256v1 | :secp256k1 | Tezex.Crypto.Curve.t()
) ::
  Tezex.Crypto.PublicKey.t()

Decodes a compressed public key to the EC public key it is representing on EC curve.

Here is a sample curve, P-256 with curve parameters from https://neuromancer.sk/std/nist/:

%Curve{
    name: :prime256v1,
    A: 0xFFFFFFFF00000001000000000000000000000000FFFFFFFFFFFFFFFFFFFFFFFC,
    B: 0x5AC635D8AA3A93E7B3EBBD55769886BC651D06B0CC53B0F63BCE3C3E27D2604B,
    P: 0xFFFFFFFF00000001000000000000000000000000FFFFFFFFFFFFFFFFFFFFFFFF,
    N: 0xFFFFFFFF00000000FFFFFFFFFFFFFFFFBCE6FAADA7179E84F3B9CAC2FC632551,
    G: %Point{
      x: 0x6B17D1F2E12C4247F8BCE6E563A440F277037D812DEB33A0F4A13945D898C296,
      y: 0x4FE342E2FE1A7F9B8EE7EB4A7C0F9E162BCE33576B315ECECBB6406837BF51F5
    }
  }

Parameters:

  • compressed_pubkey [binary/0]: the public key to decode
  • curve [Tezex.Crypto.Curve.t/0]: the curve to use (or one of :prime256v1, :secp256k1 for the two known curves supported by default)

Returns:

Link to this function

sign(message, private_key, options \\ [])

View Source 
@spec sign(iodata(), Tezex.Crypto.PrivateKey.t(), [any()]) ::
  Tezex.Crypto.Signature.t()
Link to this function

verify?(message, signature, public_key, options \\ [])

View Source 
@spec verify?(
  nonempty_binary(),
  Tezex.Crypto.Signature.t(),
  Tezex.Crypto.PublicKey.t(),
  list()
) ::
  boolean()

Verifies a message signature based on a public key

Parameters:

  • message [binary/0]: message that was signed
  • signature [Tezex.Crypto.Signature.t/0]: signature associated with the message
  • public_key [Tezex.Crypto.PublicKey.t/0]: public key associated with the message signer
  • options [kw list]: refines request
    • :hashfunc [fun/1]: hash function applied to the message. Default: fn msg -> :crypto.hash(:sha256, msg) end

Returns:

  • verified [boolean/0]: true if message, public key and signature are compatible, false otherwise