Files
ethdo/util/mnemonic.go
2022-10-29 12:10:31 +01:00

48 lines
1.6 KiB
Go

// Copyright © 2020, 2022 Weald Technology Trading
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package util
import (
"regexp"
"strings"
"github.com/pkg/errors"
"github.com/tyler-smith/go-bip39"
"golang.org/x/text/unicode/norm"
)
// hdPathRegex is the regular expression that matches an HD path.
var hdPathRegex = regexp.MustCompile("^m/[0-9]+/[0-9]+(/[0-9+])+")
// SeedFromMnemonic creates a seed from a mnemonic.
func SeedFromMnemonic(mnemonic string) ([]byte, error) {
// If there are more than 24 words we treat the additional characters as the passphrase.
mnemonicParts := strings.Split(mnemonic, " ")
mnemonicPassphrase := ""
if len(mnemonicParts) > 24 {
mnemonic = strings.Join(mnemonicParts[:24], " ")
mnemonicPassphrase = strings.Join(mnemonicParts[24:], " ")
}
// Normalise the input.
mnemonic = string(norm.NFKD.Bytes([]byte(mnemonic)))
mnemonicPassphrase = string(norm.NFKD.Bytes([]byte(mnemonicPassphrase)))
if !bip39.IsMnemonicValid(mnemonic) {
return nil, errors.New("mnemonic is invalid")
}
// Create seed from mnemonic and passphrase.
return bip39.NewSeed(mnemonic, mnemonicPassphrase), nil
}