ecdsa

Documentation

Overview

Package ecdsa implements the Elliptic Curve Digital Signature Algorithm, as defined in FIPS 186-3.

This implementation derives the nonce from an AES-CTR CSPRNG keyed by ChopMD(256, SHA2-512(priv.D || entropy || hash)). The CSPRNG key is IRO by a result of Coron; the AES-CTR stream is IRO under standard assumptions.

Index

• func Sign(rand io.Reader, priv *PrivateKey, hash []byte) (r, s *big.Int, err error)
• func Verify(pub *PublicKey, hash []byte, r, s *big.Int) bool
• type PrivateKey
  • func GenerateKey(c elliptic.Curve, rand io.Reader) (*PrivateKey, error)
  • func (priv *PrivateKey) Public() crypto.PublicKey
  • func (priv *PrivateKey) Sign(rand io.Reader, msg []byte, opts crypto.SignerOpts) ([]byte, error)
• type PublicKey

Functions

func Sign

func Sign(rand io.Reader, priv *PrivateKey, hash []byte) (r, s *big.Int, err error)

Sign signs a hash (which should be the result of hashing a larger message) using the private key, priv. If the hash is longer than the bit-length of the private key's curve order, the hash will be truncated to that length. It returns the signature as a pair of integers. The security of the private key depends on the entropy of rand.

func Verify

func Verify(pub *PublicKey, hash []byte, r, s *big.Int) bool

Verify verifies the signature in r, s of hash using the public key, pub. Its return value records whether the signature is valid.

Types

type PrivateKey

type PrivateKey struct {
	PublicKey
	D *big.Int
}

PrivateKey represents an ECDSA private key.

func GenerateKey

func GenerateKey(c elliptic.Curve, rand io.Reader) (*PrivateKey, error)

GenerateKey generates a public and private key pair.

func (*PrivateKey) Public

func (priv *PrivateKey) Public() crypto.PublicKey

Public returns the public key corresponding to priv.

func (*PrivateKey) Sign

func (priv *PrivateKey) Sign(rand io.Reader, msg []byte, opts crypto.SignerOpts) ([]byte, error)

Sign signs msg with priv, reading randomness from rand. This method is intended to support keys where the private part is kept in, for example, a hardware module. Common uses should use the Sign function in this package directly.

type PublicKey

type PublicKey struct {
	elliptic.Curve
	X, Y *big.Int
}

PublicKey represents an ECDSA public key.