// generateSeed derives an address from an HDKeychain for use in wallet. It
// outputs the seed, address, and extended public key to the file specified.
func generateSeed(filename string) error {
seed, err := hdkeychain.GenerateSeed(hdkeychain.RecommendedSeedLen)
if err != nil {
return err
}
// Derive the master extended key from the seed.
root, err := hdkeychain.NewMaster(seed, HDPrivateKeyID)
if err != nil {
return err
}
// Derive the cointype key according to BIP0044.
coinTypeKeyPriv, err := deriveCoinTypeKey(root, HDCoinType)
if err != nil {
return err
}
// Derive the account key for the first account according to BIP0044.
acctKeyPriv, err := deriveAccountKey(coinTypeKeyPriv, 0)
if err != nil {
// The seed is unusable if the any of the children in the
// required hierarchy can't be derived due to invalid child.
if err == hdkeychain.ErrInvalidChild {
return fmt.Errorf("the provided seed is unusable")
}
return err
}
// Ensure the branch keys can be derived for the provided seed according
// to BIP0044.
if err := checkBranchKeys(acctKeyPriv); err != nil {
// The seed is unusable if the any of the children in the
// required hierarchy can't be derived due to invalid child.
if err == hdkeychain.ErrInvalidChild {
return fmt.Errorf("the provided seed is unusable")
}
return err
}
// The address manager needs the public extended key for the account.
acctKeyPub, err := acctKeyPriv.Neuter()
if err != nil {
return fmt.Errorf("failed to convert private key for account 0")
}
index := uint32(0) // First address
branch := uint32(0) // External
// The next address can only be generated for accounts that have already
// been created.
acctKey := acctKeyPub
// Derive the appropriate branch key and ensure it is zeroed when done.
branchKey, err := acctKey.Child(branch)
if err != nil {
return err
}
defer branchKey.Zero() // Ensure branch key is zeroed when done.
key, err := branchKey.Child(index)
if err != nil {
return err
}
addr, err := key.Address(PubKeyHashAddrID)
if err != nil {
return err
}
var buf bytes.Buffer
buf.WriteString("First address: ")
buf.WriteString(addr.EncodeAddress())
buf.WriteString("\n")
buf.WriteString("Extended public key: ")
acctKeyStr, err := acctKey.String()
if err != nil {
return err
}
buf.WriteString(acctKeyStr)
buf.WriteString("\n")
buf.WriteString("Seed: ")
seedStr, err := pgpwordlist.ToStringChecksum(seed)
if err != nil {
return err
}
buf.WriteString(seedStr)
buf.WriteString("\n")
buf.WriteString("Seed hex: ")
buf.WriteString(fmt.Sprintf("%x", seed))
buf.WriteString("\n")
err = writeNewFile(filename, buf.Bytes(), 0644)
if err != nil {
return err
}
return nil
}
// generateSeed derives an address from an HDKeychain for use in wallet. It
// outputs the seed, address, and extended public key to the file specified.
func generateSeed(filename string) error {
seed, err := hdkeychain.GenerateSeed(hdkeychain.RecommendedSeedLen)
if err != nil {
return err
}
// Derive the master extended key from the seed.
root, err := hdkeychain.NewMaster(seed, hdPrivateKeyID)
if err != nil {
return err
}
defer root.Zero()
// Derive the cointype key according to BIP0044.
coinTypeKeyPriv, err := deriveCoinTypeKey(root, hdCoinType)
if err != nil {
return err
}
defer coinTypeKeyPriv.Zero()
// Derive the account key for the first account according to BIP0044.
acctKeyPriv, err := deriveAccountKey(coinTypeKeyPriv, 0)
if err != nil {
// The seed is unusable if the any of the children in the
// required hierarchy can't be derived due to invalid child.
if err == hdkeychain.ErrInvalidChild {
return fmt.Errorf("the provided seed is unusable")
}
return err
}
// Ensure the branch keys can be derived for the provided seed according
// to BIP0044.
if err := checkBranchKeys(acctKeyPriv); err != nil {
// The seed is unusable if the any of the children in the
// required hierarchy can't be derived due to invalid child.
if err == hdkeychain.ErrInvalidChild {
return fmt.Errorf("the provided seed is unusable")
}
return err
}
// The address manager needs the public extended key for the account.
acctKeyPub, err := acctKeyPriv.Neuter()
if err != nil {
return fmt.Errorf("failed to convert private key for account 0")
}
index := uint32(0) // First address
branch := uint32(0) // External
// The next address can only be generated for accounts that have already
// been created.
acctKey := acctKeyPub
defer acctKey.Zero()
// Derive the appropriate branch key and ensure it is zeroed when done.
branchKey, err := acctKey.Child(branch)
if err != nil {
return err
}
defer branchKey.Zero() // Ensure branch key is zeroed when done.
key, err := branchKey.Child(index)
if err != nil {
return err
}
defer key.Zero()
addr, err := key.Address(pubKeyHashAddrID)
if err != nil {
return err
}
// Require the user to write down the seed.
reader := bufio.NewReader(os.Stdin)
seedStr, err := pgpwordlist.ToStringChecksum(seed)
if err != nil {
return err
}
seedStrSplit := strings.Split(seedStr, " ")
fmt.Println("WRITE DOWN THE SEED GIVEN BELOW. YOU WILL NOT BE GIVEN " +
"ANOTHER CHANCE TO.\n")
fmt.Printf("Your wallet generation seed is:\n\n")
for i := 0; i < hdkeychain.RecommendedSeedLen+1; i++ {
fmt.Printf("%v ", seedStrSplit[i])
if (i+1)%6 == 0 {
fmt.Printf("\n")
}
}
fmt.Printf("\n\nHex: %x\n", seed)
fmt.Println("IMPORTANT: Keep the seed in a safe place as you\n" +
"will NOT be able to restore your wallet without it.")
fmt.Println("Please keep in mind that anyone who has access\n" +
"to the seed can also restore your wallet thereby\n" +
"giving them access to all your funds, so it is\n" +
"imperative that you keep it in a secure location.\n")
for {
fmt.Print("Once you have stored the seed in a safe \n" +
"and secure location, enter OK here to erase the \n" +
"seed and all derived keys from memory. Derived \n" +
"public keys and an address will be stored in the \n" +
"file specified (default: keys.txt): ")
confirmSeed, err := reader.ReadString('\n')
if err != nil {
return err
}
confirmSeed = strings.TrimSpace(confirmSeed)
confirmSeed = strings.Trim(confirmSeed, `"`)
if confirmSeed == "OK" {
break
}
}
var buf bytes.Buffer
buf.WriteString("First address: ")
buf.WriteString(addr.EncodeAddress())
buf.WriteString("\n")
buf.WriteString("Extended public key: ")
acctKeyStr, err := acctKey.String()
if err != nil {
return err
}
buf.WriteString(acctKeyStr)
buf.WriteString("\n")
// Zero the seed array.
copy(seed[:], bytes.Repeat([]byte{0x00}, 32))
err = writeNewFile(filename, buf.Bytes(), 0644)
if err != nil {
return err
}
return nil
}