bip39

README

go-bip39

A golang implementation of the BIP0039 spec for mnemonic seeds

Credits

English wordlist and test vectors are from the standard Python BIP0039 implementation from the Trezor guys: https://github.com/trezor/python-mnemonic

Example

package main

import (
  "github.com/tyler-smith/go-bip39"
  "github.com/tyler-smith/go-bip32"
  "fmt"
)

func main(){
  // Generate a mnemonic for memorization or user-friendly seeds
  entropy, _ := bip39.NewEntropy(256)
  mnemonic, _ := bip39.NewMnemonic(entropy)

  // Generate a Bip32 HD wallet for the mnemonic and a user supplied password
  seed := bip39.NewSeed(mnemonic, "Secret Passphrase")

  masterKey, _ := bip32.NewMasterKey(seed)
  publicKey := masterKey.PublicKey()

  // Display mnemonic and keys
  fmt.Println("Mnemonic: ", mnemonic)
  fmt.Println("Master private key: ", masterKey)
  fmt.Println("Master public key: ", publicKey)
}

Documentation

Overview

Package bip39 implements BIP0039 spec for mnemonic seeds.

Index

• Variables
• func IsMnemonicValid(mnemonic string) bool
• func MnemonicToByteArray(mnemonic string) ([]byte, error)
• func NewCustomSeed(mnemonic, salt []byte, iter, size int) []byte
• func NewDefaultEntropy() ([]byte, error)
• func NewEntropy(bitSize int) ([]byte, error)
• func NewMnemonic(entropy []byte) (string, error)
• func NewSeed(mnemonic, salt []byte) []byte
• func NewSeedFromString(mnemonic, salt string) []byte
• func NewSeedWithErrorChecking(mnemonic, password string) ([]byte, error)

Variables

var (
	Last11BitsMask          = big.NewInt(2047)
	RightShift11BitsDivider = big.NewInt(2048)
	BigOne                  = big.NewInt(1)
	BigTwo                  = big.NewInt(2)
)

Some bitwise operands for working with big.Ints

var EnglishWordList = []string{}/* 2048 elements not displayed */

EnglishWordList is a list of english words used to construct mnemonic.

var ReverseWordMap = make(map[string]int)

ReverseWordMap is a mapping of mnemonic words to numbers.

var WordList = EnglishWordList

WordList is the wordlist to use.

Functions

func IsMnemonicValid

func IsMnemonicValid(mnemonic string) bool

IsMnemonicValid attempts to verify that the provided mnemonic is valid. Validity is determined by both the number of words being appropriate, and that all the words in the mnemonic are present in the word list.

func MnemonicToByteArray

func MnemonicToByteArray(mnemonic string) ([]byte, error)

MnemonicToByteArray takes a mnemonic string and turns it into a byte array suitable for creating another mnemonic. An error is returned if the mnemonic is invalid. FIXME This does not work for all values in the test vectors. Namely Vectors 0, 4, and 8. This is not really important because BIP39 doesnt really define a conversion from string to bytes.

func NewCustomSeed

func NewCustomSeed(mnemonic, salt []byte, iter, size int) []byte

NewCustomSeed Creates a new key generation seed with given size from mnemonic, salt and amount of derivation iterations to perform. NewSeed creates a hashed seed output given a provided string and password. No checking is performed to validate that the string provided is a valid mnemonic.

func NewDefaultEntropy

func NewDefaultEntropy() ([]byte, error)

NewDefaultEntropy will create random entropy bytes of size 32 bits.

func NewEntropy

func NewEntropy(bitSize int) ([]byte, error)

NewEntropy will create random entropy bytes so long as the requested size bitSize is an appropriate size.

func NewMnemonic

func NewMnemonic(entropy []byte) (string, error)

NewMnemonic will return a string consisting of the mnemonic words for the given entropy. If the provide entropy is invalid, an error will be returned.

func NewSeed

func NewSeed(mnemonic, salt []byte) []byte

NewSeed creates a hashed seed output given a provided string and password. No checking is performed to validate that the string provided is a valid mnemonic.

func NewSeedFromString

func NewSeedFromString(mnemonic, salt string) []byte

NewSeedFromString creates a new hashed seed from string. See NewSeed.

func NewSeedWithErrorChecking

func NewSeedWithErrorChecking(mnemonic, password string) ([]byte, error)

NewSeedWithErrorChecking creates a hashed seed output given the mnemonic string and a password. An error is returned if the mnemonic is not convertible to a byte array.