keys package: fundraiser compatibility and HD keys (BIP 39 & BIP 32 /…

… BIP 44) (cosmos#118)

- fundraiser compatibility for HD keys (BIP 39 & BIP 32 / BIP 44)

Gopkg.toml

@@ -28,10 +28,6 @@
   name = "github.com/btcsuite/btcutil"
   branch = "master"
 
-[[constraint]]
-  name = "github.com/howeyc/crc16"
-  branch = "master"
-
 [[constraint]]
   name = "github.com/pkg/errors"
   version = "0.8.0"

Makefile

@@ -15,7 +15,7 @@ check: check_tools
 # Command to generate the workd list (kept here for documentation purposes only):
 wordlist:
 	# To re-generate wordlist.go run:
-	# go-bindata -ignore ".*\.go" -o keys/words/wordlist/wordlist.go -pkg "wordlist" keys/words/wordlist/...
+	# go-bindata -ignore ".*\.go" -o keys/words/bip39/wordlist.go -pkg "wordlist" keys/bip39/wordlist/...
 
 build: wordlist
 	# Nothing else to build!

amino.go

@@ -15,6 +15,7 @@ func init() {
 	RegisterAmino(cdc)
 }
 
+// RegisterAmino registers all go-crypto related types in the given (amino) codec.
 func RegisterAmino(cdc *amino.Codec) {
 	cdc.RegisterInterface((*PubKey)(nil), nil)
 	cdc.RegisterConcrete(PubKeyEd25519{},

armor.go

@@ -2,25 +2,25 @@ package crypto
 
 import (
 	"bytes"
+	"fmt"
 	"io/ioutil"
 
-	. "github.com/tendermint/tmlibs/common"
 	"golang.org/x/crypto/openpgp/armor"
 )
 
 func EncodeArmor(blockType string, headers map[string]string, data []byte) string {
 	buf := new(bytes.Buffer)
 	w, err := armor.Encode(buf, blockType, headers)
 	if err != nil {
-		PanicSanity("Error encoding ascii armor: " + err.Error())
+		panic(fmt.Errorf("could not encode ascii armor: %s", err))
 	}
 	_, err = w.Write(data)
 	if err != nil {
-		PanicSanity("Error encoding ascii armor: " + err.Error())
+		panic(fmt.Errorf("could not encode ascii armor: %s", err))
 	}
 	err = w.Close()
 	if err != nil {
-		PanicSanity("Error encoding ascii armor: " + err.Error())
+		panic(fmt.Errorf("could not encode ascii armor: %s", err))
 	}
 	return buf.String()
 }

keys/bcrypt/bcrypt.go

@@ -88,7 +88,7 @@ type hashed struct {
 // to compare the returned hashed password with its cleartext version.
 func GenerateFromPassword(salt []byte, password []byte, cost int) ([]byte, error) {
 	if len(salt) != maxSaltSize {
-		return nil, fmt.Errorf("Salt len must be %v", maxSaltSize)
+		return nil, fmt.Errorf("salt len must be %v", maxSaltSize)
 	}
 	p, err := newFromPassword(salt, password, cost)
 	if err != nil {

keys/bip39/wordcodec.go

@@ -0,0 +1,62 @@
+package bip39
+
+import (
+	"strings"
+
+	"github.com/bartekn/go-bip39"
+)
+
+// ValidSentenceLen defines the mnemonic sentence lengths supported by this BIP 39 library.
+type ValidSentenceLen uint8
+
+const (
+	// FundRaiser is the sentence length used during the cosmos fundraiser (12 words).
+	FundRaiser ValidSentenceLen = 12
+	// FreshKey is the sentence length used for newly created keys (24 words).
+	FreshKey ValidSentenceLen = 24
+)
+
+// NewMnemonic will return a string consisting of the mnemonic words for
+// the given sentence length.
+func NewMnemonic(len ValidSentenceLen) (words []string, err error) {
+	// len = (ENT + checksum) / 11
+	var ENT int
+	switch len {
+	case FundRaiser:
+		ENT = 128
+	case FreshKey:
+		ENT = 256
+	}
+	var entropy []byte
+	entropy, err = bip39.NewEntropy(ENT)
+	if err != nil {
+		return
+	}
+	var mnemonic string
+	mnemonic, err = bip39.NewMnemonic(entropy)
+	if err != nil {
+		return
+	}
+	words = strings.Split(mnemonic, " ")
+	return
+}
+
+// MnemonicToSeed creates a BIP 39 seed from the passed mnemonic (with an empty BIP 39 password).
+// This method does not validate the mnemonics checksum.
+func MnemonicToSeed(mne string) (seed []byte) {
+	// we do not checksum here...
+	seed = bip39.NewSeed(mne, "")
+	return
+}
+
+// MnemonicToSeedWithErrChecking returns the same seed as MnemonicToSeed.
+// It creates a BIP 39 seed from the passed mnemonic (with an empty BIP 39 password).
+//
+// Different from MnemonicToSeed it validates the checksum.
+// For details on the checksum see the BIP 39 spec.
+func MnemonicToSeedWithErrChecking(mne string) (seed []byte, err error) {
+	seed, err = bip39.NewSeedWithErrorChecking(mne, "")
+	return
+}
+
+

keys/bip39/wordcodec_test.go

@@ -0,0 +1,15 @@
+package bip39
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestWordCodec_NewMnemonic(t *testing.T) {
+	_, err := NewMnemonic(FundRaiser)
+	assert.NoError(t, err, "unexpected error generating fundraiser mnemonic")
+
+	_, err = NewMnemonic(FreshKey)
+	assert.NoError(t, err, "unexpected error generating new 24-word mnemonic")
+}