hacks/btcphrasechecker/bitcoin/derivation.go
2026-02-12 12:26:39 -08:00

149 lines
3.7 KiB
Go

package bitcoin
import (
"fmt"
"btcphrasechecker/types"
"github.com/btcsuite/btcd/btcutil"
"github.com/btcsuite/btcd/btcutil/hdkeychain"
"github.com/btcsuite/btcd/chaincfg"
"github.com/btcsuite/btcd/txscript"
)
// DerivationPath represents a BIP derivation path configuration
type DerivationPath struct {
Name string
Path string
Purpose uint32
Desc string
}
// Standard Bitcoin derivation paths
var StandardPaths = []DerivationPath{
{
Name: "BIP44 (Legacy)",
Path: "m/44'/0'/0'/0",
Purpose: 44,
Desc: "P2PKH addresses (1...)",
},
{
Name: "BIP49 (SegWit)",
Path: "m/49'/0'/0'/0",
Purpose: 49,
Desc: "P2SH-wrapped SegWit (3...)",
},
{
Name: "BIP84 (Native SegWit)",
Path: "m/84'/0'/0'/0",
Purpose: 84,
Desc: "Bech32 addresses (bc1...)",
},
}
// DeriveAddresses derives Bitcoin addresses from a seed for all standard paths
func DeriveAddresses(seed []byte, addressCount int) ([]types.AddressInfo, error) {
masterKey, err := hdkeychain.NewMaster(seed, &chaincfg.MainNetParams)
if err != nil {
return nil, fmt.Errorf("failed to create master key: %w", err)
}
var allAddresses []types.AddressInfo
for _, pathInfo := range StandardPaths {
addresses, err := derivePathAddresses(masterKey, pathInfo, addressCount)
if err != nil {
return nil, err
}
allAddresses = append(allAddresses, addresses...)
}
return allAddresses, nil
}
// derivePathAddresses derives addresses for a specific derivation path
func derivePathAddresses(masterKey *hdkeychain.ExtendedKey, pathInfo DerivationPath, count int) ([]types.AddressInfo, error) {
var addresses []types.AddressInfo
// Derive base path: m/purpose'/coin_type'/account'/change
// For Bitcoin: coin_type = 0, account = 0, change = 0 (external addresses)
key := masterKey
key, _ = key.Derive(hdkeychain.HardenedKeyStart + pathInfo.Purpose)
key, _ = key.Derive(hdkeychain.HardenedKeyStart + 0) // coin_type = 0 for Bitcoin
key, _ = key.Derive(hdkeychain.HardenedKeyStart + 0) // account = 0
key, _ = key.Derive(0) // change = 0 (external)
// Derive individual addresses
for i := uint32(0); i < uint32(count); i++ {
childKey, err := key.Derive(i)
if err != nil {
continue
}
pubKey, err := childKey.ECPubKey()
if err != nil {
continue
}
pubKeyBytes := pubKey.SerializeCompressed()
address, err := deriveAddress(pubKeyBytes, pathInfo.Purpose)
if err != nil {
continue
}
addresses = append(addresses, types.AddressInfo{
Address: address,
Path: fmt.Sprintf("%s/%d", pathInfo.Path, i),
Chain: types.ChainBitcoin,
})
}
return addresses, nil
}
// deriveAddress creates an address from a public key based on the purpose
func deriveAddress(pubKeyBytes []byte, purpose uint32) (string, error) {
switch purpose {
case 44:
// Legacy P2PKH
addr, err := btcutil.NewAddressPubKey(pubKeyBytes, &chaincfg.MainNetParams)
if err != nil {
return "", err
}
return addr.EncodeAddress(), nil
case 49:
// P2SH-wrapped SegWit (BIP49)
// Create witness program for P2WPKH
pubKeyHash := btcutil.Hash160(pubKeyBytes)
witnessProgram, err := txscript.NewScriptBuilder().
AddOp(txscript.OP_0).
AddData(pubKeyHash).
Script()
if err != nil {
return "", err
}
// Wrap witness program in P2SH
scriptAddr, err := btcutil.NewAddressScriptHash(witnessProgram, &chaincfg.MainNetParams)
if err != nil {
return "", err
}
return scriptAddr.EncodeAddress(), nil
case 84:
// Native SegWit (bech32)
addr, err := btcutil.NewAddressWitnessPubKeyHash(
btcutil.Hash160(pubKeyBytes),
&chaincfg.MainNetParams,
)
if err != nil {
return "", err
}
return addr.EncodeAddress(), nil
default:
return "", fmt.Errorf("unsupported purpose: %d", purpose)
}
}