lnd.xprv/channeldb/db.go
2020-05-22 11:26:25 +02:00

1325 lines
38 KiB
Go

package channeldb
import (
"bytes"
"encoding/binary"
"fmt"
"net"
"os"
"time"
"github.com/btcsuite/btcd/btcec"
"github.com/btcsuite/btcd/wire"
"github.com/go-errors/errors"
"github.com/lightningnetwork/lnd/channeldb/kvdb"
"github.com/lightningnetwork/lnd/channeldb/migration12"
"github.com/lightningnetwork/lnd/channeldb/migration13"
"github.com/lightningnetwork/lnd/channeldb/migration_01_to_11"
"github.com/lightningnetwork/lnd/clock"
"github.com/lightningnetwork/lnd/lnwire"
)
const (
dbName = "channel.db"
dbFilePermission = 0600
)
var (
// ErrDryRunMigrationOK signals that a migration executed successful,
// but we intentionally did not commit the result.
ErrDryRunMigrationOK = errors.New("Dry run migration successful")
)
// migration is a function which takes a prior outdated version of the database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 kvdb.RwTx) 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,
},
{
// The version of the database where two new indexes
// for the update time of node and channel updates were
// added.
number: 1,
migration: migration_01_to_11.MigrateNodeAndEdgeUpdateIndex,
},
{
// The DB version that added the invoice event time
// series.
number: 2,
migration: migration_01_to_11.MigrateInvoiceTimeSeries,
},
{
// The DB version that updated the embedded invoice in
// outgoing payments to match the new format.
number: 3,
migration: migration_01_to_11.MigrateInvoiceTimeSeriesOutgoingPayments,
},
{
// The version of the database where every channel
// always has two entries in the edges bucket. If
// a policy is unknown, this will be represented
// by a special byte sequence.
number: 4,
migration: migration_01_to_11.MigrateEdgePolicies,
},
{
// The DB version where we persist each attempt to send
// an HTLC to a payment hash, and track whether the
// payment is in-flight, succeeded, or failed.
number: 5,
migration: migration_01_to_11.PaymentStatusesMigration,
},
{
// The DB version that properly prunes stale entries
// from the edge update index.
number: 6,
migration: migration_01_to_11.MigratePruneEdgeUpdateIndex,
},
{
// The DB version that migrates the ChannelCloseSummary
// to a format where optional fields are indicated with
// boolean flags.
number: 7,
migration: migration_01_to_11.MigrateOptionalChannelCloseSummaryFields,
},
{
// The DB version that changes the gossiper's message
// store keys to account for the message's type and
// ShortChannelID.
number: 8,
migration: migration_01_to_11.MigrateGossipMessageStoreKeys,
},
{
// The DB version where the payments and payment
// statuses are moved to being stored in a combined
// bucket.
number: 9,
migration: migration_01_to_11.MigrateOutgoingPayments,
},
{
// The DB version where we started to store legacy
// payload information for all routes, as well as the
// optional TLV records.
number: 10,
migration: migration_01_to_11.MigrateRouteSerialization,
},
{
// Add invoice htlc and cltv delta fields.
number: 11,
migration: migration_01_to_11.MigrateInvoices,
},
{
// Migrate to TLV invoice bodies, add payment address
// and features, remove receipt.
number: 12,
migration: migration12.MigrateInvoiceTLV,
},
{
// Migrate to multi-path payments.
number: 13,
migration: migration13.MigrateMPP,
},
}
// Big endian is the preferred byte order, due to cursor scans over
// integer keys iterating in order.
byteOrder = binary.BigEndian
)
// 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 {
kvdb.Backend
dbPath string
graph *ChannelGraph
clock clock.Clock
dryRun bool
}
// Open opens or creates channeldb. Any necessary schemas migrations due
// to updates will take place as necessary.
// TODO(bhandras): deprecate this function.
func Open(dbPath string, modifiers ...OptionModifier) (*DB, error) {
opts := DefaultOptions()
for _, modifier := range modifiers {
modifier(&opts)
}
backend, err := kvdb.GetBoltBackend(dbPath, dbName, opts.NoFreelistSync)
if err != nil {
return nil, err
}
db, err := CreateWithBackend(backend, modifiers...)
if err == nil {
db.dbPath = dbPath
}
return db, err
}
// CreateWithBackend creates channeldb instance using the passed kvdb.Backend.
// Any necessary schemas migrations due to updates will take place as necessary.
func CreateWithBackend(backend kvdb.Backend, modifiers ...OptionModifier) (*DB, error) {
if err := initChannelDB(backend); err != nil {
return nil, err
}
opts := DefaultOptions()
for _, modifier := range modifiers {
modifier(&opts)
}
chanDB := &DB{
Backend: backend,
clock: opts.clock,
dryRun: opts.dryRun,
}
chanDB.graph = newChannelGraph(
chanDB, opts.RejectCacheSize, opts.ChannelCacheSize,
)
// Synchronize the version of database and apply migrations if needed.
if err := chanDB.syncVersions(dbVersions); err != nil {
backend.Close()
return nil, err
}
return chanDB, nil
}
// Path returns the file path to the channel database.
func (d *DB) Path() string {
return d.dbPath
}
// 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 kvdb.Update(d, func(tx kvdb.RwTx) error {
err := tx.DeleteTopLevelBucket(openChannelBucket)
if err != nil && err != kvdb.ErrBucketNotFound {
return err
}
err = tx.DeleteTopLevelBucket(closedChannelBucket)
if err != nil && err != kvdb.ErrBucketNotFound {
return err
}
err = tx.DeleteTopLevelBucket(invoiceBucket)
if err != nil && err != kvdb.ErrBucketNotFound {
return err
}
err = tx.DeleteTopLevelBucket(nodeInfoBucket)
if err != nil && err != kvdb.ErrBucketNotFound {
return err
}
err = tx.DeleteTopLevelBucket(nodeBucket)
if err != nil && err != kvdb.ErrBucketNotFound {
return err
}
err = tx.DeleteTopLevelBucket(edgeBucket)
if err != nil && err != kvdb.ErrBucketNotFound {
return err
}
err = tx.DeleteTopLevelBucket(edgeIndexBucket)
if err != nil && err != kvdb.ErrBucketNotFound {
return err
}
err = tx.DeleteTopLevelBucket(graphMetaBucket)
if err != nil && err != kvdb.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 initChannelDB(db kvdb.Backend) error {
err := kvdb.Update(db, func(tx kvdb.RwTx) error {
meta := &Meta{}
// Check if DB is already initialized.
err := fetchMeta(meta, tx)
if err == nil {
return nil
}
if _, err := tx.CreateTopLevelBucket(openChannelBucket); err != nil {
return err
}
if _, err := tx.CreateTopLevelBucket(closedChannelBucket); err != nil {
return err
}
if _, err := tx.CreateTopLevelBucket(forwardingLogBucket); err != nil {
return err
}
if _, err := tx.CreateTopLevelBucket(fwdPackagesKey); err != nil {
return err
}
if _, err := tx.CreateTopLevelBucket(invoiceBucket); err != nil {
return err
}
if _, err := tx.CreateTopLevelBucket(nodeInfoBucket); err != nil {
return err
}
nodes, err := tx.CreateTopLevelBucket(nodeBucket)
if err != nil {
return err
}
_, err = nodes.CreateBucket(aliasIndexBucket)
if err != nil {
return err
}
_, err = nodes.CreateBucket(nodeUpdateIndexBucket)
if err != nil {
return err
}
edges, err := tx.CreateTopLevelBucket(edgeBucket)
if err != nil {
return err
}
if _, err := edges.CreateBucket(edgeIndexBucket); err != nil {
return err
}
if _, err := edges.CreateBucket(edgeUpdateIndexBucket); err != nil {
return err
}
if _, err := edges.CreateBucket(channelPointBucket); err != nil {
return err
}
if _, err := edges.CreateBucket(zombieBucket); err != nil {
return err
}
graphMeta, err := tx.CreateTopLevelBucket(graphMetaBucket)
if err != nil {
return err
}
_, err = graphMeta.CreateBucket(pruneLogBucket)
if err != nil {
return err
}
if _, err := tx.CreateTopLevelBucket(metaBucket); err != nil {
return err
}
meta.DbVersionNumber = getLatestDBVersion(dbVersions)
return putMeta(meta, tx)
})
if err != nil {
return fmt.Errorf("unable to create new channeldb: %v", err)
}
return nil
}
// 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 starts a new database transaction and 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 := kvdb.View(d, func(tx kvdb.ReadTx) error {
var err error
channels, err = d.fetchOpenChannels(tx, nodeID)
return err
})
return channels, err
}
// fetchOpenChannels uses and existing database transaction and 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(tx kvdb.ReadTx,
nodeID *btcec.PublicKey) ([]*OpenChannel, error) {
// Get the bucket dedicated to storing the metadata for open channels.
openChanBucket := tx.ReadBucket(openChannelBucket)
if openChanBucket == nil {
return nil, 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.NestedReadBucket(pub)
if nodeChanBucket == nil {
return nil, nil
}
// Next, we'll need to go down an additional layer in order to retrieve
// the channels for each chain the node knows of.
var channels []*OpenChannel
err := nodeChanBucket.ForEach(func(chainHash, v []byte) error {
// If there's a value, it's not a bucket so ignore it.
if v != nil {
return nil
}
// If we've found a valid chainhash bucket, then we'll retrieve
// that so we can extract all the channels.
chainBucket := nodeChanBucket.NestedReadBucket(chainHash)
if chainBucket == nil {
return fmt.Errorf("unable to read bucket for chain=%x",
chainHash[:])
}
// Finally, we both of the necessary buckets retrieved, fetch
// all the active channels related to this node.
nodeChannels, err := d.fetchNodeChannels(chainBucket)
if err != nil {
return fmt.Errorf("unable to read channel for "+
"chain_hash=%x, node_key=%x: %v",
chainHash[:], pub, err)
}
channels = append(channels, nodeChannels...)
return nil
})
return channels, err
}
// fetchNodeChannels retrieves all active channels from the target chainBucket
// which is under a node's dedicated channel bucket. This function is typically
// used to fetch all the active channels related to a particular node.
func (d *DB) fetchNodeChannels(chainBucket kvdb.ReadBucket) ([]*OpenChannel, error) {
var channels []*OpenChannel
// A node may have channels on several chains, so for each known chain,
// we'll extract all the channels.
err := chainBucket.ForEach(func(chanPoint, v []byte) error {
// If there's a value, it's not a bucket so ignore it.
if v != nil {
return nil
}
// Once we've found a valid channel bucket, we'll extract it
// from the node's chain bucket.
chanBucket := chainBucket.NestedReadBucket(chanPoint)
var outPoint wire.OutPoint
err := readOutpoint(bytes.NewReader(chanPoint), &outPoint)
if err != nil {
return err
}
oChannel, err := fetchOpenChannel(chanBucket, &outPoint)
if err != nil {
return fmt.Errorf("unable to read channel data for "+
"chan_point=%v: %v", outPoint, err)
}
oChannel.Db = d
channels = append(channels, oChannel)
return nil
})
if err != nil {
return nil, err
}
return channels, nil
}
// FetchChannel attempts to locate a channel specified by the passed channel
// point. If the channel cannot be found, then an error will be returned.
func (d *DB) FetchChannel(chanPoint wire.OutPoint) (*OpenChannel, error) {
var (
targetChan *OpenChannel
targetChanPoint bytes.Buffer
)
if err := writeOutpoint(&targetChanPoint, &chanPoint); err != nil {
return nil, err
}
// chanScan will traverse the following bucket structure:
// * nodePub => chainHash => chanPoint
//
// At each level we go one further, ensuring that we're traversing the
// proper key (that's actually a bucket). By only reading the bucket
// structure and skipping fully decoding each channel, we save a good
// bit of CPU as we don't need to do things like decompress public
// keys.
chanScan := func(tx kvdb.ReadTx) error {
// Get the bucket dedicated to storing the metadata for open
// channels.
openChanBucket := tx.ReadBucket(openChannelBucket)
if openChanBucket == nil {
return ErrNoActiveChannels
}
// Within the node channel bucket, are the set of node pubkeys
// we have channels with, we don't know the entire set, so
// we'll check them all.
return openChanBucket.ForEach(func(nodePub, v []byte) error {
// Ensure that this is a key the same size as a pubkey,
// and also that it leads directly to a bucket.
if len(nodePub) != 33 || v != nil {
return nil
}
nodeChanBucket := openChanBucket.NestedReadBucket(nodePub)
if nodeChanBucket == nil {
return nil
}
// The next layer down is all the chains that this node
// has channels on with us.
return nodeChanBucket.ForEach(func(chainHash, v []byte) error {
// If there's a value, it's not a bucket so
// ignore it.
if v != nil {
return nil
}
chainBucket := nodeChanBucket.NestedReadBucket(
chainHash,
)
if chainBucket == nil {
return fmt.Errorf("unable to read "+
"bucket for chain=%x", chainHash[:])
}
// Finally we reach the leaf bucket that stores
// all the chanPoints for this node.
chanBucket := chainBucket.NestedReadBucket(
targetChanPoint.Bytes(),
)
if chanBucket == nil {
return nil
}
channel, err := fetchOpenChannel(
chanBucket, &chanPoint,
)
if err != nil {
return err
}
targetChan = channel
targetChan.Db = d
return nil
})
})
}
err := kvdb.View(d, chanScan)
if err != nil {
return nil, err
}
if targetChan != nil {
return targetChan, nil
}
// If we can't find the channel, then we return with an error, as we
// have nothing to backup.
return nil, ErrChannelNotFound
}
// FetchAllChannels attempts to retrieve all open channels currently stored
// within the database, including pending open, fully open and channels waiting
// for a closing transaction to confirm.
func (d *DB) FetchAllChannels() ([]*OpenChannel, error) {
return fetchChannels(d)
}
// FetchAllOpenChannels will return all channels that have the funding
// transaction confirmed, and is not waiting for a closing transaction to be
// confirmed.
func (d *DB) FetchAllOpenChannels() ([]*OpenChannel, error) {
return fetchChannels(
d,
pendingChannelFilter(false),
waitingCloseFilter(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,
pendingChannelFilter(true),
waitingCloseFilter(false),
)
}
// FetchWaitingCloseChannels will return all channels that have been opened,
// but are now waiting for a closing transaction to be confirmed.
//
// NOTE: This includes channels that are also pending to be opened.
func (d *DB) FetchWaitingCloseChannels() ([]*OpenChannel, error) {
return fetchChannels(
d, waitingCloseFilter(true),
)
}
// fetchChannelsFilter applies a filter to channels retrieved in fetchchannels.
// A set of filters can be combined to filter across multiple dimensions.
type fetchChannelsFilter func(channel *OpenChannel) bool
// pendingChannelFilter returns a filter based on whether channels are pending
// (ie, their funding transaction still needs to confirm). If pending is false,
// channels with confirmed funding transactions are returned.
func pendingChannelFilter(pending bool) fetchChannelsFilter {
return func(channel *OpenChannel) bool {
return channel.IsPending == pending
}
}
// waitingCloseFilter returns a filter which filters channels based on whether
// they are awaiting the confirmation of their closing transaction. If waiting
// close is true, channels that have had their closing tx broadcast are
// included. If it is false, channels that are not awaiting confirmation of
// their close transaction are returned.
func waitingCloseFilter(waitingClose bool) fetchChannelsFilter {
return func(channel *OpenChannel) bool {
// If the channel is in any other state than Default,
// then it means it is waiting to be closed.
channelWaitingClose :=
channel.ChanStatus() != ChanStatusDefault
// Include the channel if it matches the value for
// waiting close that we are filtering on.
return channelWaitingClose == waitingClose
}
}
// fetchChannels attempts to retrieve channels currently stored in the
// database. It takes a set of filters which are applied to each channel to
// obtain a set of channels with the desired set of properties. Only channels
// which have a true value returned for *all* of the filters will be returned.
// If no filters are provided, every channel in the open channels bucket will
// be returned.
func fetchChannels(d *DB, filters ...fetchChannelsFilter) ([]*OpenChannel, error) {
var channels []*OpenChannel
err := kvdb.View(d, func(tx kvdb.ReadTx) error {
// Get the bucket dedicated to storing the metadata for open
// channels.
openChanBucket := tx.ReadBucket(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.ReadBucket(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 particular node.
return nodeMetaBucket.ForEach(func(k, v []byte) error {
nodeChanBucket := openChanBucket.NestedReadBucket(k)
if nodeChanBucket == nil {
return nil
}
return nodeChanBucket.ForEach(func(chainHash, v []byte) error {
// If there's a value, it's not a bucket so
// ignore it.
if v != nil {
return nil
}
// If we've found a valid chainhash bucket,
// then we'll retrieve that so we can extract
// all the channels.
chainBucket := nodeChanBucket.NestedReadBucket(
chainHash,
)
if chainBucket == nil {
return fmt.Errorf("unable to read "+
"bucket for chain=%x", chainHash[:])
}
nodeChans, err := d.fetchNodeChannels(chainBucket)
if err != nil {
return fmt.Errorf("unable to read "+
"channel for chain_hash=%x, "+
"node_key=%x: %v", chainHash[:], k, err)
}
for _, channel := range nodeChans {
// includeChannel indicates whether the channel
// meets the criteria specified by our filters.
includeChannel := true
// Run through each filter and check whether the
// channel should be included.
for _, f := range filters {
// If the channel fails the filter, set
// includeChannel to false and don't bother
// checking the remaining filters.
if !f(channel) {
includeChannel = false
break
}
}
// If the channel passed every filter, include it in
// our set of channels.
if includeChannel {
channels = append(channels, channel)
}
}
return nil
})
})
})
if err != nil {
return nil, err
}
return channels, nil
}
// 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 in the 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 := kvdb.View(d, func(tx kvdb.ReadTx) error {
closeBucket := tx.ReadBucket(closedChannelBucket)
if closeBucket == nil {
return ErrNoClosedChannels
}
return closeBucket.ForEach(func(chanID []byte, summaryBytes []byte) error {
summaryReader := bytes.NewReader(summaryBytes)
chanSummary, err := deserializeCloseChannelSummary(summaryReader)
if err != nil {
return err
}
// If the query specified to only include pending
// channels, then we'll skip any channels which aren't
// currently pending.
if !chanSummary.IsPending && pendingOnly {
return nil
}
chanSummaries = append(chanSummaries, chanSummary)
return nil
})
}); err != nil {
return nil, err
}
return chanSummaries, nil
}
// ErrClosedChannelNotFound signals that a closed channel could not be found in
// the channeldb.
var ErrClosedChannelNotFound = errors.New("unable to find closed channel summary")
// FetchClosedChannel queries for a channel close summary using the channel
// point of the channel in question.
func (d *DB) FetchClosedChannel(chanID *wire.OutPoint) (*ChannelCloseSummary, error) {
var chanSummary *ChannelCloseSummary
if err := kvdb.View(d, func(tx kvdb.ReadTx) error {
closeBucket := tx.ReadBucket(closedChannelBucket)
if closeBucket == nil {
return ErrClosedChannelNotFound
}
var b bytes.Buffer
var err error
if err = writeOutpoint(&b, chanID); err != nil {
return err
}
summaryBytes := closeBucket.Get(b.Bytes())
if summaryBytes == nil {
return ErrClosedChannelNotFound
}
summaryReader := bytes.NewReader(summaryBytes)
chanSummary, err = deserializeCloseChannelSummary(summaryReader)
return err
}); err != nil {
return nil, err
}
return chanSummary, nil
}
// FetchClosedChannelForID queries for a channel close summary using the
// channel ID of the channel in question.
func (d *DB) FetchClosedChannelForID(cid lnwire.ChannelID) (
*ChannelCloseSummary, error) {
var chanSummary *ChannelCloseSummary
if err := kvdb.View(d, func(tx kvdb.ReadTx) error {
closeBucket := tx.ReadBucket(closedChannelBucket)
if closeBucket == nil {
return ErrClosedChannelNotFound
}
// The first 30 bytes of the channel ID and outpoint will be
// equal.
cursor := closeBucket.ReadCursor()
op, c := cursor.Seek(cid[:30])
// We scan over all possible candidates for this channel ID.
for ; op != nil && bytes.Compare(cid[:30], op[:30]) <= 0; op, c = cursor.Next() {
var outPoint wire.OutPoint
err := readOutpoint(bytes.NewReader(op), &outPoint)
if err != nil {
return err
}
// If the found outpoint does not correspond to this
// channel ID, we continue.
if !cid.IsChanPoint(&outPoint) {
continue
}
// Deserialize the close summary and return.
r := bytes.NewReader(c)
chanSummary, err = deserializeCloseChannelSummary(r)
if err != nil {
return err
}
return nil
}
return ErrClosedChannelNotFound
}); err != nil {
return nil, err
}
return chanSummary, 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 reached 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 kvdb.Update(d, func(tx kvdb.RwTx) error {
var b bytes.Buffer
if err := writeOutpoint(&b, chanPoint); err != nil {
return err
}
chanID := b.Bytes()
closedChanBucket, err := tx.CreateTopLevelBucket(
closedChannelBucket,
)
if err != nil {
return err
}
chanSummaryBytes := closedChanBucket.Get(chanID)
if chanSummaryBytes == nil {
return fmt.Errorf("no closed channel for "+
"chan_point=%v found", chanPoint)
}
chanSummaryReader := bytes.NewReader(chanSummaryBytes)
chanSummary, err := deserializeCloseChannelSummary(
chanSummaryReader,
)
if err != nil {
return err
}
chanSummary.IsPending = false
var newSummary bytes.Buffer
err = serializeChannelCloseSummary(&newSummary, chanSummary)
if err != nil {
return err
}
err = closedChanBucket.Put(chanID, newSummary.Bytes())
if err != nil {
return err
}
// Now that the channel is closed, we'll check if we have any
// other open channels with this peer. If we don't we'll
// garbage collect it to ensure we don't establish persistent
// connections to peers without open channels.
return d.pruneLinkNode(tx, chanSummary.RemotePub)
})
}
// pruneLinkNode determines whether we should garbage collect a link node from
// the database due to no longer having any open channels with it. If there are
// any left, then this acts as a no-op.
func (d *DB) pruneLinkNode(tx kvdb.RwTx, remotePub *btcec.PublicKey) error {
openChannels, err := d.fetchOpenChannels(tx, remotePub)
if err != nil {
return fmt.Errorf("unable to fetch open channels for peer %x: "+
"%v", remotePub.SerializeCompressed(), err)
}
if len(openChannels) > 0 {
return nil
}
log.Infof("Pruning link node %x with zero open channels from database",
remotePub.SerializeCompressed())
return d.deleteLinkNode(tx, remotePub)
}
// PruneLinkNodes attempts to prune all link nodes found within the databse with
// whom we no longer have any open channels with.
func (d *DB) PruneLinkNodes() error {
return kvdb.Update(d, func(tx kvdb.RwTx) error {
linkNodes, err := d.fetchAllLinkNodes(tx)
if err != nil {
return err
}
for _, linkNode := range linkNodes {
err := d.pruneLinkNode(tx, linkNode.IdentityPub)
if err != nil {
return err
}
}
return nil
})
}
// ChannelShell is a shell of a channel that is meant to be used for channel
// recovery purposes. It contains a minimal OpenChannel instance along with
// addresses for that target node.
type ChannelShell struct {
// NodeAddrs the set of addresses that this node has known to be
// reachable at in the past.
NodeAddrs []net.Addr
// Chan is a shell of an OpenChannel, it contains only the items
// required to restore the channel on disk.
Chan *OpenChannel
}
// RestoreChannelShells is a method that allows the caller to reconstruct the
// state of an OpenChannel from the ChannelShell. We'll attempt to write the
// new channel to disk, create a LinkNode instance with the passed node
// addresses, and finally create an edge within the graph for the channel as
// well. This method is idempotent, so repeated calls with the same set of
// channel shells won't modify the database after the initial call.
func (d *DB) RestoreChannelShells(channelShells ...*ChannelShell) error {
chanGraph := d.ChannelGraph()
// TODO(conner): find way to do this w/o accessing internal members?
chanGraph.cacheMu.Lock()
defer chanGraph.cacheMu.Unlock()
var chansRestored []uint64
err := kvdb.Update(d, func(tx kvdb.RwTx) error {
for _, channelShell := range channelShells {
channel := channelShell.Chan
// When we make a channel, we mark that the channel has
// been restored, this will signal to other sub-systems
// to not attempt to use the channel as if it was a
// regular one.
channel.chanStatus |= ChanStatusRestored
// First, we'll attempt to create a new open channel
// and link node for this channel. If the channel
// already exists, then in order to ensure this method
// is idempotent, we'll continue to the next step.
channel.Db = d
err := syncNewChannel(
tx, channel, channelShell.NodeAddrs,
)
if err != nil {
return err
}
// Next, we'll create an active edge in the graph
// database for this channel in order to restore our
// partial view of the network.
//
// TODO(roasbeef): if we restore *after* the channel
// has been closed on chain, then need to inform the
// router that it should try and prune these values as
// we can detect them
edgeInfo := ChannelEdgeInfo{
ChannelID: channel.ShortChannelID.ToUint64(),
ChainHash: channel.ChainHash,
ChannelPoint: channel.FundingOutpoint,
Capacity: channel.Capacity,
}
nodes := tx.ReadWriteBucket(nodeBucket)
if nodes == nil {
return ErrGraphNotFound
}
selfNode, err := chanGraph.sourceNode(nodes)
if err != nil {
return err
}
// Depending on which pub key is smaller, we'll assign
// our roles as "node1" and "node2".
chanPeer := channel.IdentityPub.SerializeCompressed()
selfIsSmaller := bytes.Compare(
selfNode.PubKeyBytes[:], chanPeer,
) == -1
if selfIsSmaller {
copy(edgeInfo.NodeKey1Bytes[:], selfNode.PubKeyBytes[:])
copy(edgeInfo.NodeKey2Bytes[:], chanPeer)
} else {
copy(edgeInfo.NodeKey1Bytes[:], chanPeer)
copy(edgeInfo.NodeKey2Bytes[:], selfNode.PubKeyBytes[:])
}
// With the edge info shell constructed, we'll now add
// it to the graph.
err = chanGraph.addChannelEdge(tx, &edgeInfo)
if err != nil && err != ErrEdgeAlreadyExist {
return err
}
// Similarly, we'll construct a channel edge shell and
// add that itself to the graph.
chanEdge := ChannelEdgePolicy{
ChannelID: edgeInfo.ChannelID,
LastUpdate: time.Now(),
}
// If their pubkey is larger, then we'll flip the
// direction bit to indicate that us, the "second" node
// is updating their policy.
if !selfIsSmaller {
chanEdge.ChannelFlags |= lnwire.ChanUpdateDirection
}
_, err = updateEdgePolicy(tx, &chanEdge)
if err != nil {
return err
}
chansRestored = append(chansRestored, edgeInfo.ChannelID)
}
return nil
})
if err != nil {
return err
}
for _, chanid := range chansRestored {
chanGraph.rejectCache.remove(chanid)
chanGraph.chanCache.remove(chanid)
}
return nil
}
// AddrsForNode consults the graph and channel database for all addresses known
// to the passed node public key.
func (d *DB) AddrsForNode(nodePub *btcec.PublicKey) ([]net.Addr, error) {
var (
linkNode *LinkNode
graphNode LightningNode
)
dbErr := kvdb.View(d, func(tx kvdb.ReadTx) error {
var err error
linkNode, err = fetchLinkNode(tx, nodePub)
if err != nil {
return err
}
// We'll also query the graph for this peer to see if they have
// any addresses that we don't currently have stored within the
// link node database.
nodes := tx.ReadBucket(nodeBucket)
if nodes == nil {
return ErrGraphNotFound
}
compressedPubKey := nodePub.SerializeCompressed()
graphNode, err = fetchLightningNode(nodes, compressedPubKey)
if err != nil && err != ErrGraphNodeNotFound {
// If the node isn't found, then that's OK, as we still
// have the link node data.
return err
}
return nil
})
if dbErr != nil {
return nil, dbErr
}
// Now that we have both sources of addrs for this node, we'll use a
// map to de-duplicate any addresses between the two sources, and
// produce a final list of the combined addrs.
addrs := make(map[string]net.Addr)
for _, addr := range linkNode.Addresses {
addrs[addr.String()] = addr
}
for _, addr := range graphNode.Addresses {
addrs[addr.String()] = addr
}
dedupedAddrs := make([]net.Addr, 0, len(addrs))
for _, addr := range addrs {
dedupedAddrs = append(dedupedAddrs, addr)
}
return dedupedAddrs, nil
}
// AbandonChannel attempts to remove the target channel from the open channel
// database. If the channel was already removed (has a closed channel entry),
// then we'll return a nil error. Otherwise, we'll insert a new close summary
// into the database.
func (d *DB) AbandonChannel(chanPoint *wire.OutPoint, bestHeight uint32) error {
// With the chanPoint constructed, we'll attempt to find the target
// channel in the database. If we can't find the channel, then we'll
// return the error back to the caller.
dbChan, err := d.FetchChannel(*chanPoint)
switch {
// If the channel wasn't found, then it's possible that it was already
// abandoned from the database.
case err == ErrChannelNotFound:
_, closedErr := d.FetchClosedChannel(chanPoint)
if closedErr != nil {
return closedErr
}
// If the channel was already closed, then we don't return an
// error as we'd like fro this step to be repeatable.
return nil
case err != nil:
return err
}
// Now that we've found the channel, we'll populate a close summary for
// the channel, so we can store as much information for this abounded
// channel as possible. We also ensure that we set Pending to false, to
// indicate that this channel has been "fully" closed.
summary := &ChannelCloseSummary{
CloseType: Abandoned,
ChanPoint: *chanPoint,
ChainHash: dbChan.ChainHash,
CloseHeight: bestHeight,
RemotePub: dbChan.IdentityPub,
Capacity: dbChan.Capacity,
SettledBalance: dbChan.LocalCommitment.LocalBalance.ToSatoshis(),
ShortChanID: dbChan.ShortChanID(),
RemoteCurrentRevocation: dbChan.RemoteCurrentRevocation,
RemoteNextRevocation: dbChan.RemoteNextRevocation,
LocalChanConfig: dbChan.LocalChanCfg,
}
// Finally, we'll close the channel in the DB, and return back to the
// caller. We set ourselves as the close initiator because we abandoned
// the channel.
return dbChan.CloseChannel(summary, ChanStatusLocalCloseInitiator)
}
// 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
}
}
latestVersion := getLatestDBVersion(versions)
log.Infof("Checking for schema update: latest_version=%v, "+
"db_version=%v", latestVersion, meta.DbVersionNumber)
switch {
// If the database reports a higher version that we are aware of, the
// user is probably trying to revert to a prior version of lnd. We fail
// here to prevent reversions and unintended corruption.
case meta.DbVersionNumber > latestVersion:
log.Errorf("Refusing to revert from db_version=%d to "+
"lower version=%d", meta.DbVersionNumber,
latestVersion)
return ErrDBReversion
// If the current database version matches the latest version number,
// then we don't need to perform any migrations.
case 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 kvdb.Update(d, func(tx kvdb.RwTx) 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
err := putMeta(meta, tx)
if err != nil {
return err
}
// In dry-run mode, return an error to prevent the transaction
// from committing.
if d.dryRun {
return ErrDryRunMigrationOK
}
return nil
})
}
// ChannelGraph returns a new instance of the directed channel graph.
func (d *DB) ChannelGraph() *ChannelGraph {
return d.graph
}
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
}
// fetchHistoricalChanBucket returns a the channel bucket for a given outpoint
// from the historical channel bucket. If the bucket does not exist,
// ErrNoHistoricalBucket is returned.
func fetchHistoricalChanBucket(tx kvdb.ReadTx,
outPoint *wire.OutPoint) (kvdb.ReadBucket, error) {
// First fetch the top level bucket which stores all data related to
// historically stored channels.
historicalChanBucket := tx.ReadBucket(historicalChannelBucket)
if historicalChanBucket == nil {
return nil, ErrNoHistoricalBucket
}
// With the bucket for the node and chain fetched, we can now go down
// another level, for the channel itself.
var chanPointBuf bytes.Buffer
if err := writeOutpoint(&chanPointBuf, outPoint); err != nil {
return nil, err
}
chanBucket := historicalChanBucket.NestedReadBucket(chanPointBuf.Bytes())
if chanBucket == nil {
return nil, ErrChannelNotFound
}
return chanBucket, nil
}
// FetchHistoricalChannel fetches open channel data from the historical channel
// bucket.
func (d *DB) FetchHistoricalChannel(outPoint *wire.OutPoint) (*OpenChannel, error) {
var channel *OpenChannel
err := kvdb.View(d, func(tx kvdb.ReadTx) error {
chanBucket, err := fetchHistoricalChanBucket(tx, outPoint)
if err != nil {
return err
}
channel, err = fetchOpenChannel(chanBucket, outPoint)
return err
})
if err != nil {
return nil, err
}
return channel, nil
}