Refactor genimportscript command

Author: guggero

README.md

@@ -274,7 +274,9 @@ Usage:
 
 [genimportscript command options]
           --rootkey=        BIP32 HD root key to use. Leave empty to prompt for lnd 24 word aezeed.
-          --format=         The format of the generated import script. Currently supported are: bitcoin-cli, bitcoin-cli-watchonly.
+          --format=         The format of the generated import script. Currently supported are: bitcoin-cli, bitcoin-cli-watchonly, bitcoin-importwallet.
+          --lndpaths        Use all derivation paths that lnd uses. Results in a large number of results. Cannot be used in conjunction with --derivationpath.
+          --derivationpath= Use one specific derivation path. Specify the first levels of the derivation path before any internal/external branch. Cannot be used in conjunction with --lndpaths. (default m/84'/0'/0')
           --recoverywindow= The number of keys to scan per internal/external branch. The output will consist of double this amount of keys. (default 2500)
           --rescanfrom=     The block number to rescan from. Will be set automatically from the wallet birthday if the lnd 24 word aezeed is entered. (default 500000)
 ```

btc/bitcoind.go

@@ -0,0 +1,217 @@
+package btc
+
+import (
+	"fmt"
+	"io"
+	"time"
+
+	"github.com/btcsuite/btcd/chaincfg"
+	"github.com/btcsuite/btcd/txscript"
+	"github.com/btcsuite/btcutil"
+	"github.com/btcsuite/btcutil/hdkeychain"
+	"github.com/guggero/chantools/lnd"
+)
+
+const (
+	FormatCli          = "bitcoin-cli"
+	FormatCliWatchOnly = "bitcoin-cli-watchonly"
+	FormatImportwallet = "bitcoin-importwallet"
+)
+
+type KeyExporter interface {
+	Header() string
+	Format(*hdkeychain.ExtendedKey, *chaincfg.Params, string, uint32,
+		uint32) (string, error)
+	Trailer(uint32) string
+}
+
+// ParseFormat parses the given format name and returns its associated print
+// function.
+func ParseFormat(format string) KeyExporter {
+	switch format {
+	default:
+		fallthrough
+
+	case FormatCli:
+		return &Cli{}
+
+	case FormatCliWatchOnly:
+		return &CliWatchOnly{}
+
+	case FormatImportwallet:
+		return &ImportWallet{}
+	}
+}
+
+func ExportKeys(extendedKey *hdkeychain.ExtendedKey, strPaths []string,
+	paths [][]uint32, params *chaincfg.Params, recoveryWindow,
+	rescanFrom uint32, exporter KeyExporter, writer io.Writer) error {
+
+	_, _ = fmt.Fprintf(
+		writer, "# Wallet dump created by chantools on %s\n",
+		time.Now().UTC(),
+	)
+	_, _ = fmt.Fprintf(writer, "%s\n", exporter.Header())
+	for idx, strPath := range strPaths {
+		path := paths[idx]
+
+		// External branch first (<DerivationPath>/0/i).
+		for i := uint32(0); i < recoveryWindow; i++ {
+			path := append(path, 0, i)
+			derivedKey, err := lnd.DeriveChildren(extendedKey, path)
+			if err != nil {
+				return err
+			}
+			result, err := exporter.Format(
+				derivedKey, params, strPath, 0, i,
+			)
+			if err != nil {
+				return err
+			}
+			_, _ = fmt.Fprintf(writer, "%s\n", result)
+		}
+
+		// Now the internal branch (<DerivationPath>/1/i).
+		for i := uint32(0); i < recoveryWindow; i++ {
+			path := append(path, 1, i)
+			derivedKey, err := lnd.DeriveChildren(extendedKey, path)
+			if err != nil {
+				return err
+			}
+			result, err := exporter.Format(
+				derivedKey, params, strPath, 1, i,
+			)
+			if err != nil {
+				return err
+			}
+			_, _ = fmt.Fprintf(writer, "%s\n", result)
+		}
+	}
+
+	_, _ = fmt.Fprintf(writer, "%s\n", exporter.Trailer(rescanFrom))
+	return nil
+}
+
+func SeedBirthdayToBlock(params *chaincfg.Params,
+	birthdayTimestamp time.Time) uint32 {
+
+	var genesisTimestamp time.Time
+	switch params.Name {
+	case "mainnet":
+		genesisTimestamp =
+			chaincfg.MainNetParams.GenesisBlock.Header.Timestamp
+
+	case "testnet3":
+		genesisTimestamp =
+			chaincfg.TestNet3Params.GenesisBlock.Header.Timestamp
+
+	case "regtest", "simnet":
+		return 0
+
+	default:
+		panic(fmt.Errorf("unimplemented network %v", params.Name))
+	}
+
+	// With the timestamps retrieved, we can estimate a block height by
+	// taking the difference between them and dividing by the average block
+	// time (10 minutes).
+	return uint32(birthdayTimestamp.Sub(genesisTimestamp).Seconds() / 600)
+}
+
+type Cli struct{}
+
+func (c *Cli) Header() string {
+	return "# Paste the following lines into a command line window."
+}
+
+func (c *Cli) Format(hdKey *hdkeychain.ExtendedKey, params *chaincfg.Params,
+	path string, branch, index uint32) (string, error) {
+
+	privKey, err := hdKey.ECPrivKey()
+	if err != nil {
+		return "", fmt.Errorf("could not derive private key: %v", err)
+	}
+	wif, err := btcutil.NewWIF(privKey, params, true)
+	if err != nil {
+		return "", fmt.Errorf("could not encode WIF: %v", err)
+	}
+	return fmt.Sprintf("bitcoin-cli importprivkey %s \"%s/%d/%d/\" false",
+		wif.String(), path, branch, index), nil
+}
+
+func (c *Cli) Trailer(birthdayBlock uint32) string {
+	return fmt.Sprintf("bitcoin-cli rescanblockchain %d\n", birthdayBlock)
+}
+
+type CliWatchOnly struct{}
+
+func (c *CliWatchOnly) Header() string {
+	return "# Paste the following lines into a command line window."
+}
+
+func (c *CliWatchOnly) Format(hdKey *hdkeychain.ExtendedKey, _ *chaincfg.Params,
+	path string, branch, index uint32) (string, error) {
+
+	pubKey, err := hdKey.ECPubKey()
+	if err != nil {
+		return "", fmt.Errorf("could not derive private key: %v", err)
+	}
+	return fmt.Sprintf("bitcoin-cli importpubkey %x \"%s/%d/%d/\" false",
+		pubKey.SerializeCompressed(), path, branch, index), nil
+}
+
+func (c *CliWatchOnly) Trailer(birthdayBlock uint32) string {
+	return fmt.Sprintf("bitcoin-cli rescanblockchain %d\n", birthdayBlock)
+}
+
+type ImportWallet struct{}
+
+func (i *ImportWallet) Header() string {
+	return "# Save this output to a file and use the importwallet " +
+		"command of bitcoin core."
+}
+
+func (i *ImportWallet) Format(hdKey *hdkeychain.ExtendedKey,
+	params *chaincfg.Params, path string, branch, index uint32) (string,
+	error) {
+
+	privKey, err := hdKey.ECPrivKey()
+	if err != nil {
+		return "", fmt.Errorf("could not derive private key: %v", err)
+	}
+	wif, err := btcutil.NewWIF(privKey, params, true)
+	if err != nil {
+		return "", fmt.Errorf("could not encode WIF: %v", err)
+	}
+	pubKey, err := hdKey.ECPubKey()
+	if err != nil {
+		return "", fmt.Errorf("could not derive private key: %v", err)
+	}
+	hash160 := btcutil.Hash160(pubKey.SerializeCompressed())
+	addrP2PKH, err := btcutil.NewAddressPubKeyHash(hash160, params)
+	if err != nil {
+		return "", fmt.Errorf("could not create address: %v", err)
+	}
+	addrP2WKH, err := btcutil.NewAddressWitnessPubKeyHash(hash160, params)
+	if err != nil {
+		return "", fmt.Errorf("could not create address: %v", err)
+	}
+	script, err := txscript.PayToAddrScript(addrP2WKH)
+	if err != nil {
+		return "", fmt.Errorf("could not create script: %v", err)
+	}
+	addrNP2WKH, err := btcutil.NewAddressScriptHash(script, params)
+	if err != nil {
+		return "", fmt.Errorf("could not create address: %v", err)
+	}
+
+	return fmt.Sprintf("%s 1970-01-01T00:00:01Z label=%s/%d/%d/ "+
+		"# addr=%s,%s,%s", wif.String(), path, branch, index,
+		addrP2PKH.EncodeAddress(), addrNP2WKH.EncodeAddress(),
+		addrP2WKH.EncodeAddress(),
+	), nil
+}
+
+func (i *ImportWallet) Trailer(_ uint32) string {
+	return ""
+}