lnd.xprv/channeldb/db.go
Olaoluwa Osuntokun 66ba2e862c
channeldb: store the funding transaction broadcast height for channels
This commit expands the field within the OpenChannel struct in order to
start tracking the height that the funding transaction was initially
broadcast. Other sub-systems within lnd can now use this data to give a
more accurate height hint to the ChainNotifier, or to use during the
funding workflow to decide if a channel should be forgotten after it
fails to confirm for N blocks.
2017-06-05 19:15:44 -07:00

556 lines
15 KiB
Go

package channeldb
import (
"bytes"
"encoding/binary"
"fmt"
"os"
"path/filepath"
"sync"
"github.com/boltdb/bolt"
"github.com/roasbeef/btcd/btcec"
"github.com/roasbeef/btcd/wire"
)
const (
dbName = "channel.db"
dbFilePermission = 0600
)
// migration is a function which takes a prior outdated version of the database
// instances and mutates the key/bucket structure to arrive at a more
// up-to-date version of the database.
type migration func(tx *bolt.Tx) error
type version struct {
number uint32
migration migration
}
var (
// dbVersions is storing all versions of database. If current version
// of database don't match with latest version this list will be used
// for retrieving all migration function that are need to apply to the
// current db.
dbVersions = []version{
{
// The base DB version requires no migration.
number: 0,
migration: nil,
},
{
number: 1,
migration: deliveryScriptBugMigration,
},
}
// Big endian is the preferred byte order, due to cursor scans over
// integer keys iterating in order.
byteOrder = binary.BigEndian
)
var bufPool = &sync.Pool{
New: func() interface{} { return new(bytes.Buffer) },
}
// DB is the primary datastore for the lnd daemon. The database stores
// information related to nodes, routing data, open/closed channels, fee
// schedules, and reputation data.
type DB struct {
*bolt.DB
dbPath string
}
// Open opens an existing channeldb. Any necessary schemas migrations due to
// updates will take place as necessary.
func Open(dbPath string) (*DB, error) {
path := filepath.Join(dbPath, dbName)
if !fileExists(path) {
if err := createChannelDB(dbPath); err != nil {
return nil, err
}
}
bdb, err := bolt.Open(path, dbFilePermission, nil)
if err != nil {
return nil, err
}
chanDB := &DB{
DB: bdb,
dbPath: dbPath,
}
// Synchronize the version of database and apply migrations if needed.
if err := chanDB.syncVersions(dbVersions); err != nil {
bdb.Close()
return nil, err
}
return chanDB, nil
}
// Wipe completely deletes all saved state within all used buckets within the
// database. The deletion is done in a single transaction, therefore this
// operation is fully atomic.
func (d *DB) Wipe() error {
return d.Update(func(tx *bolt.Tx) error {
err := tx.DeleteBucket(openChannelBucket)
if err != nil && err != bolt.ErrBucketNotFound {
return err
}
err = tx.DeleteBucket(closedChannelBucket)
if err != nil && err != bolt.ErrBucketNotFound {
return err
}
err = tx.DeleteBucket(invoiceBucket)
if err != nil && err != bolt.ErrBucketNotFound {
return err
}
err = tx.DeleteBucket(nodeInfoBucket)
if err != nil && err != bolt.ErrBucketNotFound {
return err
}
err = tx.DeleteBucket(nodeBucket)
if err != nil && err != bolt.ErrBucketNotFound {
return err
}
err = tx.DeleteBucket(edgeBucket)
if err != nil && err != bolt.ErrBucketNotFound {
return err
}
err = tx.DeleteBucket(edgeIndexBucket)
if err != nil && err != bolt.ErrBucketNotFound {
return err
}
err = tx.DeleteBucket(graphMetaBucket)
if err != nil && err != bolt.ErrBucketNotFound {
return err
}
return nil
})
}
// createChannelDB creates and initializes a fresh version of channeldb. In
// the case that the target path has not yet been created or doesn't yet exist,
// then the path is created. Additionally, all required top-level buckets used
// within the database are created.
func createChannelDB(dbPath string) error {
if !fileExists(dbPath) {
if err := os.MkdirAll(dbPath, 0700); err != nil {
return err
}
}
path := filepath.Join(dbPath, dbName)
bdb, err := bolt.Open(path, dbFilePermission, nil)
if err != nil {
return err
}
err = bdb.Update(func(tx *bolt.Tx) error {
if _, err := tx.CreateBucket(openChannelBucket); err != nil {
return err
}
if _, err := tx.CreateBucket(closedChannelBucket); err != nil {
return err
}
if _, err := tx.CreateBucket(invoiceBucket); err != nil {
return err
}
if _, err := tx.CreateBucket(nodeInfoBucket); err != nil {
return err
}
if _, err := tx.CreateBucket(nodeBucket); err != nil {
return err
}
if _, err := tx.CreateBucket(edgeBucket); err != nil {
return err
}
if _, err := tx.CreateBucket(edgeIndexBucket); err != nil {
return err
}
if _, err := tx.CreateBucket(graphMetaBucket); err != nil {
return err
}
if _, err := tx.CreateBucket(metaBucket); err != nil {
return err
}
meta := &Meta{
DbVersionNumber: getLatestDBVersion(dbVersions),
}
return putMeta(meta, tx)
})
if err != nil {
return fmt.Errorf("unable to create new channeldb")
}
return bdb.Close()
}
// fileExists returns true if the file exists, and false otherwise.
func fileExists(path string) bool {
if _, err := os.Stat(path); err != nil {
if os.IsNotExist(err) {
return false
}
}
return true
}
// FetchOpenChannels returns all stored currently active/open channels
// associated with the target nodeID. In the case that no active channels are
// known to have been created with this node, then a zero-length slice is
// returned.
func (d *DB) FetchOpenChannels(nodeID *btcec.PublicKey) ([]*OpenChannel, error) {
var channels []*OpenChannel
err := d.View(func(tx *bolt.Tx) error {
// Get the bucket dedicated to storing the metadata for open
// channels.
openChanBucket := tx.Bucket(openChannelBucket)
if openChanBucket == nil {
return nil
}
// Within this top level bucket, fetch the bucket dedicated to storing
// open channel data specific to the remote node.
pub := nodeID.SerializeCompressed()
nodeChanBucket := openChanBucket.Bucket(pub)
if nodeChanBucket == nil {
return nil
}
// Finally, we both of the necessary buckets retrieved, fetch
// all the active channels related to this node.
nodeChannels, err := d.fetchNodeChannels(openChanBucket,
nodeChanBucket)
if err != nil {
return fmt.Errorf("unable to read channel for "+
"node_key=%x: %v", pub, err)
}
channels = nodeChannels
return nil
})
return channels, err
}
// fetchNodeChannels retrieves all active channels from the target
// nodeChanBucket. This function is typically used to fetch all the active
// channels related to a particular node.
func (d *DB) fetchNodeChannels(openChanBucket,
nodeChanBucket *bolt.Bucket) ([]*OpenChannel, error) {
var channels []*OpenChannel
// Once we have the node's channel bucket, iterate through each
// item in the inner chan ID bucket. This bucket acts as an
// index for all channels we currently have open with this node.
nodeChanIDBucket := nodeChanBucket.Bucket(chanIDBucket[:])
if nodeChanIDBucket == nil {
return nil, nil
}
err := nodeChanIDBucket.ForEach(func(k, v []byte) error {
if k == nil {
return nil
}
outBytes := bytes.NewReader(k)
chanID := &wire.OutPoint{}
if err := readOutpoint(outBytes, chanID); err != nil {
return err
}
oChannel, err := fetchOpenChannel(openChanBucket,
nodeChanBucket, chanID)
if err != nil {
return fmt.Errorf("unable to read channel data for "+
"chan_point=%v: %v", chanID, err)
}
oChannel.Db = d
channels = append(channels, oChannel)
return nil
})
if err != nil {
return nil, err
}
return channels, nil
}
// FetchAllChannels attempts to retrieve all open channels currently stored
// within the database.
func (d *DB) FetchAllChannels() ([]*OpenChannel, error) {
return fetchChannels(d, false)
}
// FetchPendingChannels will return channels that have completed the process
// of generating and broadcasting funding transactions, but whose funding
// transactions have yet to be confirmed on the blockchain.
func (d *DB) FetchPendingChannels() ([]*OpenChannel, error) {
return fetchChannels(d, true)
}
// fetchChannels attempts to retrieve channels currently stored in the
// database. The pendingOnly parameter determines whether only pending
// channels will be returned. If no active channels exist within the network,
// then ErrNoActiveChannels is returned.
func fetchChannels(d *DB, pendingOnly bool) ([]*OpenChannel, error) {
var channels []*OpenChannel
err := d.View(func(tx *bolt.Tx) error {
// Get the bucket dedicated to storing the metadata for open
// channels.
openChanBucket := tx.Bucket(openChannelBucket)
if openChanBucket == nil {
return ErrNoActiveChannels
}
// Next, fetch the bucket dedicated to storing metadata
// related to all nodes. All keys within this bucket are the
// serialized public keys of all our direct counterparties.
nodeMetaBucket := tx.Bucket(nodeInfoBucket)
if nodeMetaBucket == nil {
return fmt.Errorf("node bucket not created")
}
// Finally for each node public key in the bucket, fetch all
// the channels related to this particualr ndoe.
return nodeMetaBucket.ForEach(func(k, v []byte) error {
nodeChanBucket := openChanBucket.Bucket(k)
if nodeChanBucket == nil {
return nil
}
nodeChannels, err := d.fetchNodeChannels(openChanBucket,
nodeChanBucket)
if err != nil {
return fmt.Errorf("unable to read channel for "+
"node_key=%x: %v", k, err)
}
// TODO(roasbeef): simplify
if pendingOnly {
for _, channel := range nodeChannels {
if channel.IsPending {
channels = append(channels, channel)
}
}
} else {
channels = append(channels, nodeChannels...)
}
return nil
})
})
return channels, err
}
// MarkChannelAsOpen records the finalization of the funding process and marks
// a channel as available for use. Additionally the height in which this
// channel as opened will also be recorded within the database.
func (d *DB) MarkChannelAsOpen(outpoint *wire.OutPoint, openHeight uint32) error {
return d.Update(func(tx *bolt.Tx) error {
openChanBucket := tx.Bucket(openChannelBucket)
if openChanBucket == nil {
return ErrNoActiveChannels
}
// Generate the database key, which will consist of the
// IsPending prefix followed by the channel's outpoint.
var b bytes.Buffer
if err := writeOutpoint(&b, outpoint); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix[3:], b.Bytes())
copy(keyPrefix[:3], isPendingPrefix)
// For the database value, store a zero, since the channel is
// no longer pending.
scratch := make([]byte, 4)
byteOrder.PutUint16(scratch[:2], uint16(0))
if err := openChanBucket.Put(keyPrefix, scratch[:2]); err != nil {
return err
}
// Finally, we'll also store the opening height for this
// channel as well.
confInfoKey := make([]byte, len(confInfoPrefix)+len(b.Bytes()))
copy(confInfoKey[:len(confInfoPrefix)], confInfoPrefix)
copy(confInfoKey[len(confInfoPrefix):], b.Bytes())
confInfoBytes := openChanBucket.Get(confInfoKey)
infoCopy := make([]byte, len(confInfoBytes))
copy(infoCopy[:], confInfoBytes)
byteOrder.PutUint32(infoCopy[4:], openHeight)
return openChanBucket.Put(confInfoKey, infoCopy)
})
}
// FetchClosedChannels attempts to fetch all closed channels from the database.
// The pendingOnly bool toggles if channels that aren't yet fully closed should
// be returned int he response or not. When a channel was cooperatively closed,
// it becomes fully closed after a single confirmation. When a channel was
// forcibly closed, it will become fully closed after _all_ the pending funds
// (if any) have been swept.
func (d *DB) FetchClosedChannels(pendingOnly bool) ([]*ChannelCloseSummary, error) {
var chanSummaries []*ChannelCloseSummary
if err := d.View(func(tx *bolt.Tx) error {
closeBucket := tx.Bucket(closedChannelBucket)
if closeBucket == nil {
return ErrNoClosedChannels
}
return closeBucket.ForEach(func(chanID []byte, summaryBytes []byte) error {
// The first byte of the summary is a bool which
// indicates if this channel is pending closure, or has
// been fully closed.
isPending := summaryBytes[0]
// If the query specified to only include pending
// channels, then we'll skip any channels which aren't
// currently pending.
if pendingOnly && isPending != 0x01 {
return nil
}
summaryReader := bytes.NewReader(summaryBytes)
chanSummary, err := deserializeCloseChannelSummary(summaryReader)
if err != nil {
return err
}
chanSummaries = append(chanSummaries, chanSummary)
return nil
})
}); err != nil {
return nil, err
}
return chanSummaries, nil
}
// MarkChanFullyClosed marks a channel as fully closed within the database. A
// channel should be marked as fully closed if the channel was initially
// cooperatively closed and it's reach a single confirmation, or after all the
// pending funds in a channel that has been forcibly closed have been swept.
func (d *DB) MarkChanFullyClosed(chanPoint *wire.OutPoint) error {
return d.Update(func(tx *bolt.Tx) error {
var b bytes.Buffer
if err := writeOutpoint(&b, chanPoint); err != nil {
return err
}
chanID := b.Bytes()
closedChanBucket, err := tx.CreateBucketIfNotExists(closedChannelBucket)
if err != nil {
return err
}
chanSummary := closedChanBucket.Get(chanID)
if chanSummary == nil {
return fmt.Errorf("no closed channel by that chanID found")
}
newSummary := make([]byte, len(chanSummary))
copy(newSummary[:], chanSummary[:])
newSummary[0] = 0x00
return closedChanBucket.Put(chanID, newSummary)
})
}
// syncVersions function is used for safe db version synchronization. It applies
// migration functions to the current database and recovers the previous
// state of db if at least one error/panic appeared during migration.
func (d *DB) syncVersions(versions []version) error {
meta, err := d.FetchMeta(nil)
if err != nil {
if err == ErrMetaNotFound {
meta = &Meta{}
} else {
return err
}
}
// If the current database version matches the latest version number,
// then we don't need to perform any migrations.
latestVersion := getLatestDBVersion(versions)
log.Infof("Checking for schema update: latest_version=%v, "+
"db_version=%v", latestVersion, meta.DbVersionNumber)
if meta.DbVersionNumber == latestVersion {
return nil
}
log.Infof("Performing database schema migration")
// Otherwise, we fetch the migrations which need to applied, and
// execute them serially within a single database transaction to ensure
// the migration is atomic.
migrations, migrationVersions := getMigrationsToApply(versions,
meta.DbVersionNumber)
return d.Update(func(tx *bolt.Tx) error {
for i, migration := range migrations {
if migration == nil {
continue
}
log.Infof("Applying migration #%v", migrationVersions[i])
if err := migration(tx); err != nil {
log.Infof("Unable to apply migration #%v",
migrationVersions[i])
return err
}
}
meta.DbVersionNumber = latestVersion
return putMeta(meta, tx)
})
}
// ChannelGraph returns a new instance of the directed channel graph.
func (d *DB) ChannelGraph() *ChannelGraph {
return &ChannelGraph{d}
}
func getLatestDBVersion(versions []version) uint32 {
return versions[len(versions)-1].number
}
// getMigrationsToApply retrieves the migration function that should be
// applied to the database.
func getMigrationsToApply(versions []version, version uint32) ([]migration, []uint32) {
migrations := make([]migration, 0, len(versions))
migrationVersions := make([]uint32, 0, len(versions))
for _, v := range versions {
if v.number > version {
migrations = append(migrations, v.migration)
migrationVersions = append(migrationVersions, v.number)
}
}
return migrations, migrationVersions
}