ed25519

README

ed25519

Golang ed25519 with extended functionality

Documentation

Overview

Package ed25519 implements the Ed25519 signature algorithm. See https://ed25519.cr.yp.to/.

These functions are also compatible with the “Ed25519” function defined in RFC 8032. However, unlike RFC 8032's formulation, this package's private key representation includes a public key suffix to make multiple signing operations with the same key more efficient. This package refers to the RFC 8032 private key as the “seed”.

Index

• Constants
• func GenerateExtendedKey(rand io.Reader) (PublicKey, ExtendedPrivateKey, error)
• func GenerateKey(rand io.Reader) (PublicKey, PrivateKey, error)
• func Sign(privateKey PrivateKey, message []byte) []byte
• func SignExtended(extendedPrivateKey ExtendedPrivateKey, message []byte) []byte
• func Verify(publicKey PublicKey, message, sig []byte) bool
• type ExtendedPrivateKey
  • func (xpriv ExtendedPrivateKey) Public() crypto.PublicKey
  • func (xpriv ExtendedPrivateKey) Sign(rand io.Reader, message []byte, opts crypto.SignerOpts) (signature []byte, err error)
• type PrivateKey
  • func NewKeyFromSeed(seed []byte) PrivateKey
  • func (priv PrivateKey) Equal(x crypto.PrivateKey) bool
  • func (priv PrivateKey) Public() crypto.PublicKey
  • func (priv PrivateKey) Seed() []byte
  • func (priv PrivateKey) Sign(rand io.Reader, message []byte, opts crypto.SignerOpts) (signature []byte, err error)
• type PublicKey
  • func PublicKeyFrom(extendedPrivateKey ExtendedPrivateKey) PublicKey
  • func (pub PublicKey) Equal(x crypto.PublicKey) bool

Constants

const (
	// PublicKeySize is the size, in bytes, of public keys as used in this package.
	PublicKeySize = 32
	// PrivateKeySize is the size, in bytes, of private keys as used in this package.
	PrivateKeySize = 64
	// ExtendedPrivateKeySize is the size, in bytes, of extended private keys as used in this package.
	ExtendedPrivateKeySize = 64
	// SignatureSize is the size, in bytes, of signatures generated and verified by this package.
	SignatureSize = 64
	// SeedSize is the size, in bytes, of private key seeds. These are the private key representations used by RFC 8032.
	SeedSize = 32
)

Functions

func GenerateExtendedKey

func GenerateExtendedKey(rand io.Reader) (PublicKey, ExtendedPrivateKey, error)

GenerateExtendedKey generates a public/private(extended) key pair using entropy from rand. If rand is nil, crypto/rand.Reader will be used.

func GenerateKey

func GenerateKey(rand io.Reader) (PublicKey, PrivateKey, error)

GenerateKey generates a public/private key pair using entropy from rand. If rand is nil, crypto/rand.Reader will be used.

func Sign

func Sign(privateKey PrivateKey, message []byte) []byte

Sign signs the message with privateKey and returns a signature. It will panic if len(privateKey) is not PrivateKeySize.

func SignExtended

func SignExtended(extendedPrivateKey ExtendedPrivateKey, message []byte) []byte

SignExtended the message with extendedPrivateKey and returns a signature. It will panic if len(extendedPrivateKey) is not ExtendedPrivateKeySize.

func Verify

func Verify(publicKey PublicKey, message, sig []byte) bool

Verify reports whether sig is a valid signature of message by publicKey. It will panic if len(publicKey) is not PublicKeySize.

Types

type ExtendedPrivateKey

type ExtendedPrivateKey []byte

ExtendedPrivateKey is the type of Ed25519 private keys. It implements crypto.Signer.

func (ExtendedPrivateKey) Public

func (xpriv ExtendedPrivateKey) Public() crypto.PublicKey

Public returns the PublicKey corresponding to priv.

func (ExtendedPrivateKey) Sign

func (xpriv ExtendedPrivateKey) Sign(rand io.Reader, message []byte, opts crypto.SignerOpts) (signature []byte, err error)

Sign signs the given message with xpriv. Ed25519 performs two passes over messages to be signed and therefore cannot handle pre-hashed messages. Thus opts.HashFunc() must return zero to indicate the message hasn't been hashed. This can be achieved by passing crypto.Hash(0) as the value for opts.

type PrivateKey

type PrivateKey []byte

PrivateKey is the type of Ed25519 private keys. It implements crypto.Signer.

func NewKeyFromSeed

func NewKeyFromSeed(seed []byte) PrivateKey

NewKeyFromSeed calculates a private key from a seed. It will panic if len(seed) is not SeedSize. This function is provided for interoperability with RFC 8032. RFC 8032's private keys correspond to seeds in this package.

func (PrivateKey) Equal

func (priv PrivateKey) Equal(x crypto.PrivateKey) bool

Equal reports whether priv and x have the same value.

func (PrivateKey) Public

func (priv PrivateKey) Public() crypto.PublicKey

Public returns the PublicKey corresponding to priv.

func (PrivateKey) Seed

func (priv PrivateKey) Seed() []byte

Seed returns the private key seed corresponding to priv. It is provided for interoperability with RFC 8032. RFC 8032's private keys correspond to seeds in this package.

func (PrivateKey) Sign

func (priv PrivateKey) Sign(rand io.Reader, message []byte, opts crypto.SignerOpts) (signature []byte, err error)

Sign signs the given message with priv. Ed25519 performs two passes over messages to be signed and therefore cannot handle pre-hashed messages. Thus opts.HashFunc() must return zero to indicate the message hasn't been hashed. This can be achieved by passing crypto.Hash(0) as the value for opts.

type PublicKey

type PublicKey []byte

PublicKey is the type of Ed25519 public keys.

func PublicKeyFrom

func PublicKeyFrom(extendedPrivateKey ExtendedPrivateKey) PublicKey

PublicKeyFrom returns the PublicKey corresponding to extendedPrivateKey.

func (PublicKey) Equal

func (pub PublicKey) Equal(x crypto.PublicKey) bool

Equal reports whether pub and x have the same value.