Add chanbackup command

README.md

@@ -5,6 +5,7 @@
 * [Installation](#installation)
 * [Overview](#overview)
 * [Commands](#commands)
+  + [chanbackup](#chanbackup)
   + [derivekey](#derivekey)
   + [dumpbackup](#dumpbackup)
   + [dumpchannels](#dumpchannels)
@@ -57,6 +58,7 @@ Help Options:
   -h, --help             Show this help message
 
 Available commands:
+  chanbackup       Create a channel.backup file from a channel database.
   derivekey        Derive a key with a specific derivation path from the BIP32 HD root key.
   dumpbackup       Dump the content of a channel.backup file.
   dumpchannels     Dump all channel information from lnd's channel database.
@@ -73,6 +75,28 @@ Available commands:
 
 ## Commands
 
+### chanbackup
+
+```text
+Usage:
+  chantools [OPTIONS] chanbackup [chanbackup-OPTIONS]
+
+[chanbackup command options]
+          --rootkey=     BIP32 HD root key of the wallet that should be used to create the backup. Leave empty to prompt for lnd 24 word aezeed.
+          --channeldb=   The lnd channel.db file to create the backup from.
+          --multi_file=  The lnd channel.backup file to create.
+```
+
+This command creates a new channel.backup from a channel.db file.
+
+Example command:
+
+```bash
+chantools chanbackup --rootkey xprvxxxxxxxxxx \
+  --channeldb ~/.lnd/data/graph/mainnet/channel.db \
+  --multi_file new_channel_backup.backup 
+```
+
 ### derivekey
 
 ```text

cmd/chantools/chanbackup.go

@@ -0,0 +1,83 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"github.com/guggero/chantools/btc"
+	"github.com/lightningnetwork/lnd/chanbackup"
+	"github.com/lightningnetwork/lnd/keychain"
+	"path"
+
+	"github.com/btcsuite/btcutil/hdkeychain"
+	"github.com/lightningnetwork/lnd/channeldb"
+)
+
+type chanBackupCommand struct {
+	RootKey   string `long:"rootkey" description:"BIP32 HD root key of the wallet that should be used to create the backup. Leave empty to prompt for lnd 24 word aezeed."`
+	ChannelDB string `long:"channeldb" description:"The lnd channel.db file to create the backup from."`
+	MultiFile string `long:"multi_file" description:"The lnd channel.backup file to create."`
+}
+
+func (c *chanBackupCommand) Execute(_ []string) error {
+	setupChainParams(cfg)
+
+	var (
+		extendedKey *hdkeychain.ExtendedKey
+		err         error
+	)
+
+	// Check that root key is valid or fall back to console input.
+	switch {
+	case c.RootKey != "":
+		extendedKey, err = hdkeychain.NewKeyFromString(c.RootKey)
+
+	default:
+		extendedKey, _, err = rootKeyFromConsole()
+	}
+	if err != nil {
+		return fmt.Errorf("error reading root key: %v", err)
+	}
+
+	// Check that we have a backup file.
+	if c.MultiFile == "" {
+		return fmt.Errorf("backup file is required")
+	}
+
+	// Check that we have a channel DB.
+	if c.ChannelDB == "" {
+		return fmt.Errorf("channel DB is required")
+	}
+	db, err := channeldb.Open(path.Dir(c.ChannelDB))
+	if err != nil {
+		return fmt.Errorf("error opening rescue DB: %v", err)
+	}
+	multiFile := chanbackup.NewMultiFile(c.MultiFile)
+	keyRing := &btc.HDKeyRing{
+		ExtendedKey: extendedKey,
+		ChainParams: chainParams,
+	}
+	return createChannelBackup(db, multiFile, keyRing)
+}
+
+func createChannelBackup(db *channeldb.DB, multiFile *chanbackup.MultiFile,
+	ring keychain.KeyRing) error {
+
+	singles, err := chanbackup.FetchStaticChanBackups(db)
+	if err != nil {
+		return fmt.Errorf("error extracting channel backup: %v", err)
+	}
+	multi := &chanbackup.Multi{
+		Version: chanbackup.DefaultMultiVersion,
+		StaticBackups: singles,
+	}
+	var b bytes.Buffer
+	err = multi.PackToWriter(&b, ring)
+	if err != nil {
+		return fmt.Errorf("unable to pack backup: %v", err)
+	}
+	err = multiFile.UpdateAndSwap(b.Bytes())
+	if err != nil {
+		return fmt.Errorf("unable to write backup file: %v", err)
+	}
+	return nil
+}

cmd/chantools/main.go

@@ -5,6 +5,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"fmt"
+	"github.com/lightningnetwork/lnd/chanbackup"
 	"io/ioutil"
 	"os"
 	"strings"
@@ -12,6 +13,7 @@ import (
 	"time"
 
 	"github.com/btcsuite/btcd/chaincfg"
+	"github.com/btcsuite/btclog"
 	"github.com/btcsuite/btcutil/hdkeychain"
 	"github.com/guggero/chantools/dataformat"
 	"github.com/jessevdk/go-flags"
@@ -115,6 +117,10 @@ func runCommandParser() error {
 			"wallet.db file and optionally extracts the BIP32 HD "+
 			"root key.", "", &walletInfoCommand{},
 	)
+	_, _ = parser.AddCommand(
+		"chanbackup", "Create a channel.backup file from a channel "+
+			"database.", "", &chanBackupCommand{},
+	)
 
 	_, err := parser.Parse()
 	return err
@@ -258,7 +264,9 @@ func setupChainParams(cfg *config) {
 }
 
 func setupLogging() {
-	logWriter.RegisterSubLogger("CHAN", log)
+	setSubLogger("CHAN", log)
+	addSubLogger("CHDB", channeldb.UseLogger)
+	addSubLogger("BCKP", chanbackup.UseLogger)
 	err := logWriter.InitLogRotator("./results/chantools.log", 10, 3)
 	if err != nil {
 		panic(err)
@@ -269,6 +277,26 @@ func setupLogging() {
 	}
 }
 
+// addSubLogger is a helper method to conveniently create and register the
+// logger of one or more sub systems.
+func addSubLogger(subsystem string, useLoggers ...func(btclog.Logger)) {
+	// Create and register just a single logger to prevent them from
+	// overwriting each other internally.
+	logger := build.NewSubLogger(subsystem, logWriter.GenSubLogger)
+	setSubLogger(subsystem, logger, useLoggers...)
+}
+
+// setSubLogger is a helper method to conveniently register the logger of a sub
+// system.
+func setSubLogger(subsystem string, logger btclog.Logger,
+	useLoggers ...func(btclog.Logger)) {
+
+	logWriter.RegisterSubLogger(subsystem, logger)
+	for _, useLogger := range useLoggers {
+		useLogger(logger)
+	}
+}
+
 func noConsole() ([]byte, error) {
 	return nil, fmt.Errorf("wallet db requires console access")
 }

go.mod

@@ -4,6 +4,7 @@ require (
 	git.schwanenlied.me/yawning/bsaes.git v0.0.0-20190320102049-26d1add596b6 // indirect
 	github.com/Yawning/aez v0.0.0-20180408160647-ec7426b44926 // indirect
 	github.com/btcsuite/btcd v0.20.1-beta
+	github.com/btcsuite/btclog v0.0.0-20170628155309-84c8d2346e9f
 	github.com/btcsuite/btcutil v0.0.0-20191219182022-e17c9730c422
 	github.com/btcsuite/btcwallet v0.11.0
 	github.com/btcsuite/btcwallet/walletdb v1.1.0