lnd.xprv/channeldb/migrations.go
Wilmer Paulino 85ea08fd17
channeldb: add migration to properly prune edge update index
In this commit, we introduce a migration to fix some of the recent
issues found w.r.t. the edge update index. The migration attempts to fix
two things:

1) Edge policies include an extra byte at the end due to reading an
extra byte for the node's public key from the serialized node info.

2) Properly prune all stale entries within the edge update index.

As a result of this migration, nodes will have a slightly smaller in
size channeldb. We will also no longer send stale edges to our peers in
response to their gossip queries, which should also fix the fetching
channel announcement for closed channels issue.
2018-09-04 18:33:43 -07:00

566 lines
17 KiB
Go

package channeldb
import (
"bytes"
"crypto/sha256"
"encoding/binary"
"errors"
"fmt"
"github.com/coreos/bbolt"
)
// migrateNodeAndEdgeUpdateIndex is a migration function that will update the
// database from version 0 to version 1. In version 1, we add two new indexes
// (one for nodes and one for edges) to keep track of the last time a node or
// edge was updated on the network. These new indexes allow us to implement the
// new graph sync protocol added.
func migrateNodeAndEdgeUpdateIndex(tx *bolt.Tx) error {
// First, we'll populating the node portion of the new index. Before we
// can add new values to the index, we'll first create the new bucket
// where these items will be housed.
nodes, err := tx.CreateBucketIfNotExists(nodeBucket)
if err != nil {
return fmt.Errorf("unable to create node bucket: %v", err)
}
nodeUpdateIndex, err := nodes.CreateBucketIfNotExists(
nodeUpdateIndexBucket,
)
if err != nil {
return fmt.Errorf("unable to create node update index: %v", err)
}
log.Infof("Populating new node update index bucket")
// Now that we know the bucket has been created, we'll iterate over the
// entire node bucket so we can add the (updateTime || nodePub) key
// into the node update index.
err = nodes.ForEach(func(nodePub, nodeInfo []byte) error {
if len(nodePub) != 33 {
return nil
}
log.Tracef("Adding %x to node update index", nodePub)
// The first 8 bytes of a node's serialize data is the update
// time, so we can extract that without decoding the entire
// structure.
updateTime := nodeInfo[:8]
// Now that we have the update time, we can construct the key
// to insert into the index.
var indexKey [8 + 33]byte
copy(indexKey[:8], updateTime)
copy(indexKey[8:], nodePub)
return nodeUpdateIndex.Put(indexKey[:], nil)
})
if err != nil {
return fmt.Errorf("unable to update node indexes: %v", err)
}
log.Infof("Populating new edge update index bucket")
// With the set of nodes updated, we'll now update all edges to have a
// corresponding entry in the edge update index.
edges, err := tx.CreateBucketIfNotExists(edgeBucket)
if err != nil {
return fmt.Errorf("unable to create edge bucket: %v", err)
}
edgeUpdateIndex, err := edges.CreateBucketIfNotExists(
edgeUpdateIndexBucket,
)
if err != nil {
return fmt.Errorf("unable to create edge update index: %v", err)
}
// We'll now run through each edge policy in the database, and update
// the index to ensure each edge has the proper record.
err = edges.ForEach(func(edgeKey, edgePolicyBytes []byte) error {
if len(edgeKey) != 41 {
return nil
}
// Now that we know this is the proper record, we'll grab the
// channel ID (last 8 bytes of the key), and then decode the
// edge policy so we can access the update time.
chanID := edgeKey[33:]
edgePolicyReader := bytes.NewReader(edgePolicyBytes)
edgePolicy, err := deserializeChanEdgePolicy(
edgePolicyReader, nodes,
)
if err != nil {
return err
}
log.Tracef("Adding chan_id=%v to edge update index",
edgePolicy.ChannelID)
// We'll now construct the index key using the channel ID, and
// the last time it was updated: (updateTime || chanID).
var indexKey [8 + 8]byte
byteOrder.PutUint64(
indexKey[:], uint64(edgePolicy.LastUpdate.Unix()),
)
copy(indexKey[8:], chanID)
return edgeUpdateIndex.Put(indexKey[:], nil)
})
if err != nil {
return fmt.Errorf("unable to update edge indexes: %v", err)
}
log.Infof("Migration to node and edge update indexes complete!")
return nil
}
// migrateInvoiceTimeSeries is a database migration that assigns all existing
// invoices an index in the add and/or the settle index. Additionally, all
// existing invoices will have their bytes padded out in order to encode the
// add+settle index as well as the amount paid.
func migrateInvoiceTimeSeries(tx *bolt.Tx) error {
invoices, err := tx.CreateBucketIfNotExists(invoiceBucket)
if err != nil {
return err
}
addIndex, err := invoices.CreateBucketIfNotExists(
addIndexBucket,
)
if err != nil {
return err
}
settleIndex, err := invoices.CreateBucketIfNotExists(
settleIndexBucket,
)
if err != nil {
return err
}
log.Infof("Migrating invoice database to new time series format")
// Now that we have all the buckets we need, we'll run through each
// invoice in the database, and update it to reflect the new format
// expected post migration.
err = invoices.ForEach(func(invoiceNum, invoiceBytes []byte) error {
// If this is a sub bucket, then we'll skip it.
if invoiceBytes == nil {
return nil
}
// First, we'll make a copy of the encoded invoice bytes.
invoiceBytesCopy := make([]byte, len(invoiceBytes))
copy(invoiceBytesCopy, invoiceBytes)
// With the bytes copied over, we'll append 24 additional
// bytes. We do this so we can decode the invoice under the new
// serialization format.
padding := bytes.Repeat([]byte{0}, 24)
invoiceBytesCopy = append(invoiceBytesCopy, padding...)
invoiceReader := bytes.NewReader(invoiceBytesCopy)
invoice, err := deserializeInvoice(invoiceReader)
if err != nil {
return fmt.Errorf("unable to decode invoice: %v", err)
}
// Now that we have the fully decoded invoice, we can update
// the various indexes that we're added, and finally the
// invoice itself before re-inserting it.
// First, we'll get the new sequence in the addIndex in order
// to create the proper mapping.
nextAddSeqNo, err := addIndex.NextSequence()
if err != nil {
return err
}
var seqNoBytes [8]byte
byteOrder.PutUint64(seqNoBytes[:], nextAddSeqNo)
err = addIndex.Put(seqNoBytes[:], invoiceNum[:])
if err != nil {
return err
}
log.Tracef("Adding invoice (preimage=%x, add_index=%v) to add "+
"time series", invoice.Terms.PaymentPreimage[:],
nextAddSeqNo)
// Next, we'll check if the invoice has been settled or not. If
// so, then we'll also add it to the settle index.
var nextSettleSeqNo uint64
if invoice.Terms.Settled {
nextSettleSeqNo, err = settleIndex.NextSequence()
if err != nil {
return err
}
var seqNoBytes [8]byte
byteOrder.PutUint64(seqNoBytes[:], nextSettleSeqNo)
err := settleIndex.Put(seqNoBytes[:], invoiceNum)
if err != nil {
return err
}
invoice.AmtPaid = invoice.Terms.Value
log.Tracef("Adding invoice (preimage=%x, "+
"settle_index=%v) to add time series",
invoice.Terms.PaymentPreimage[:],
nextSettleSeqNo)
}
// Finally, we'll update the invoice itself with the new
// indexing information as well as the amount paid if it has
// been settled or not.
invoice.AddIndex = nextAddSeqNo
invoice.SettleIndex = nextSettleSeqNo
// We've fully migrated an invoice, so we'll now update the
// invoice in-place.
var b bytes.Buffer
if err := serializeInvoice(&b, &invoice); err != nil {
return err
}
return invoices.Put(invoiceNum, b.Bytes())
})
if err != nil {
return err
}
log.Infof("Migration to invoice time series index complete!")
return nil
}
// migrateInvoiceTimeSeriesOutgoingPayments is a follow up to the
// migrateInvoiceTimeSeries migration. As at the time of writing, the
// OutgoingPayment struct embeddeds an instance of the Invoice struct. As a
// result, we also need to migrate the internal invoice to the new format.
func migrateInvoiceTimeSeriesOutgoingPayments(tx *bolt.Tx) error {
payBucket := tx.Bucket(paymentBucket)
if payBucket == nil {
return nil
}
log.Infof("Migrating invoice database to new outgoing payment format")
err := payBucket.ForEach(func(payID, paymentBytes []byte) error {
log.Tracef("Migrating payment %x", payID[:])
// The internal invoices for each payment only contain a
// populated contract term, and creation date, as a result,
// most of the bytes will be "empty".
// We'll calculate the end of the invoice index assuming a
// "minimal" index that's embedded within the greater
// OutgoingPayment. The breakdown is:
// 3 bytes empty var bytes, 16 bytes creation date, 16 bytes
// settled date, 32 bytes payment pre-image, 8 bytes value, 1
// byte settled.
endOfInvoiceIndex := 1 + 1 + 1 + 16 + 16 + 32 + 8 + 1
// We'll now extract the prefix of the pure invoice embedded
// within.
invoiceBytes := paymentBytes[:endOfInvoiceIndex]
// With the prefix extracted, we'll copy over the invoice, and
// also add padding for the new 24 bytes of fields, and finally
// append the remainder of the outgoing payment.
paymentCopy := make([]byte, len(invoiceBytes))
copy(paymentCopy[:], invoiceBytes)
padding := bytes.Repeat([]byte{0}, 24)
paymentCopy = append(paymentCopy, padding...)
paymentCopy = append(
paymentCopy, paymentBytes[endOfInvoiceIndex:]...,
)
// At this point, we now have the new format of the outgoing
// payments, we'll attempt to deserialize it to ensure the
// bytes are properly formatted.
paymentReader := bytes.NewReader(paymentCopy)
_, err := deserializeOutgoingPayment(paymentReader)
if err != nil {
return fmt.Errorf("unable to deserialize payment: %v", err)
}
// Now that we know the modifications was successful, we'll
// write it back to disk in the new format.
if err := payBucket.Put(payID, paymentCopy); err != nil {
return err
}
return nil
})
if err != nil {
return err
}
log.Infof("Migration to outgoing payment invoices complete!")
return nil
}
// migrateEdgePolicies is a migration function that will update the edges
// bucket. It ensure that edges with unknown policies will also have an entry
// in the bucket. After the migration, there will be two edge entries for
// every channel, regardless of whether the policies are known.
func migrateEdgePolicies(tx *bolt.Tx) error {
nodes := tx.Bucket(nodeBucket)
if nodes == nil {
return nil
}
edges := tx.Bucket(edgeBucket)
if edges == nil {
return nil
}
edgeIndex := edges.Bucket(edgeIndexBucket)
if edgeIndex == nil {
return nil
}
// checkKey gets the policy from the database with a low-level call
// so that it is still possible to distinguish between unknown and
// not present.
checkKey := func(channelId uint64, keyBytes []byte) error {
var channelID [8]byte
byteOrder.PutUint64(channelID[:], channelId)
_, err := fetchChanEdgePolicy(edges,
channelID[:], keyBytes, nodes)
if err == ErrEdgeNotFound {
log.Tracef("Adding unknown edge policy present for node %x, channel %v",
keyBytes, channelId)
err := putChanEdgePolicyUnknown(edges, channelId, keyBytes)
if err != nil {
return err
}
return nil
}
return err
}
// Iterate over all channels and check both edge policies.
err := edgeIndex.ForEach(func(chanID, edgeInfoBytes []byte) error {
infoReader := bytes.NewReader(edgeInfoBytes)
edgeInfo, err := deserializeChanEdgeInfo(infoReader)
if err != nil {
return err
}
for _, key := range [][]byte{edgeInfo.NodeKey1Bytes[:],
edgeInfo.NodeKey2Bytes[:]} {
if err := checkKey(edgeInfo.ChannelID, key); err != nil {
return err
}
}
return nil
})
if err != nil {
return fmt.Errorf("unable to update edge policies: %v", err)
}
log.Infof("Migration of edge policies complete!")
return nil
}
// paymentStatusesMigration is a database migration intended for adding payment
// statuses for each existing payment entity in bucket to be able control
// transitions of statuses and prevent cases such as double payment
func paymentStatusesMigration(tx *bolt.Tx) error {
// Get the bucket dedicated to storing statuses of payments,
// where a key is payment hash, value is payment status.
paymentStatuses, err := tx.CreateBucketIfNotExists(paymentStatusBucket)
if err != nil {
return err
}
log.Infof("Migrating database to support payment statuses")
circuitAddKey := []byte("circuit-adds")
circuits := tx.Bucket(circuitAddKey)
if circuits != nil {
log.Infof("Marking all known circuits with status InFlight")
err = circuits.ForEach(func(k, v []byte) error {
// Parse the first 8 bytes as the short chan ID for the
// circuit. We'll skip all short chan IDs are not
// locally initiated, which includes all non-zero short
// chan ids.
chanID := binary.BigEndian.Uint64(k[:8])
if chanID != 0 {
return nil
}
// The payment hash is the third item in the serialized
// payment circuit. The first two items are an AddRef
// (10 bytes) and the incoming circuit key (16 bytes).
const payHashOffset = 10 + 16
paymentHash := v[payHashOffset : payHashOffset+32]
return paymentStatuses.Put(
paymentHash[:], StatusInFlight.Bytes(),
)
})
if err != nil {
return err
}
}
log.Infof("Marking all existing payments with status Completed")
// Get the bucket dedicated to storing payments
bucket := tx.Bucket(paymentBucket)
if bucket == nil {
return nil
}
// For each payment in the bucket, deserialize the payment and mark it
// as completed.
err = bucket.ForEach(func(k, v []byte) error {
// Ignores if it is sub-bucket.
if v == nil {
return nil
}
r := bytes.NewReader(v)
payment, err := deserializeOutgoingPayment(r)
if err != nil {
return err
}
// Calculate payment hash for current payment.
paymentHash := sha256.Sum256(payment.PaymentPreimage[:])
// Update status for current payment to completed. If it fails,
// the migration is aborted and the payment bucket is returned
// to its previous state.
return paymentStatuses.Put(paymentHash[:], StatusCompleted.Bytes())
})
if err != nil {
return err
}
log.Infof("Migration of payment statuses complete!")
return nil
}
// migratePruneEdgeUpdateIndex is a database migration that attempts to resolve
// some lingering bugs with regards to edge policies and their update index.
// Stale entries within the edge update index were not being properly pruned due
// to a miscalculation on the offset of an edge's policy last update. This
// migration also fixes the case where the public keys within edge policies were
// being serialized with an extra byte, causing an even greater error when
// attempting to perform the offset calculation described earlier.
func migratePruneEdgeUpdateIndex(tx *bolt.Tx) error {
// To begin the migration, we'll retrieve the update index bucket. If it
// does not exist, we have nothing left to do so we can simply exit.
edges := tx.Bucket(edgeBucket)
if edges == nil {
return nil
}
edgeUpdateIndex := edges.Bucket(edgeUpdateIndexBucket)
if edgeUpdateIndex == nil {
return nil
}
// Retrieve some buckets that will be needed later on. These should
// already exist given the assumption that the buckets above do as well.
edgeIndex := edges.Bucket(edgeIndexBucket)
if edgeIndex == nil {
return errors.New("edge index should exist but does not")
}
nodes := tx.Bucket(nodeBucket)
if nodes == nil {
return errors.New("node bucket should exist but does not")
}
log.Info("Migrating database to properly prune edge update index")
// We'll need to properly prune all the outdated entries within the edge
// update index. To do so, we'll gather all of the existing policies
// within the graph to re-populate them later on.
var edgeKeys [][]byte
err := edges.ForEach(func(edgeKey, edgePolicyBytes []byte) error {
// All valid entries are indexed by a public key (33 bytes)
// followed by a channel ID (8 bytes), so we'll skip any entries
// with keys that do not match this.
if len(edgeKey) != 33+8 {
return nil
}
edgeKeys = append(edgeKeys, edgeKey)
return nil
})
if err != nil {
return fmt.Errorf("unable to gather existing edge policies: %v",
err)
}
// With the existing edge policies gathered, we'll recreate the index
// and populate it with the correct entries.
oldNumEntries := edgeUpdateIndex.Stats().KeyN
if err := edges.DeleteBucket(edgeUpdateIndexBucket); err != nil {
return fmt.Errorf("unable to remove existing edge update "+
"index: %v", err)
}
edgeUpdateIndex, err = edges.CreateBucketIfNotExists(
edgeUpdateIndexBucket,
)
if err != nil {
return fmt.Errorf("unable to recreate edge update index: %v",
err)
}
// For each edge key, we'll retrieve the policy, deserialize it, and
// re-add it to the different buckets. By doing so, we'll ensure that
// all existing edge policies are serialized correctly within their
// respective buckets and that the correct entries are populated within
// the edge update index.
for _, edgeKey := range edgeKeys {
edgePolicyBytes := edges.Get(edgeKey)
// Skip any entries with unknown policies as there will not be
// any entries for them in the edge update index.
if bytes.Equal(edgePolicyBytes[:], unknownPolicy) {
continue
}
edgePolicy, err := deserializeChanEdgePolicy(
bytes.NewReader(edgePolicyBytes), nodes,
)
if err != nil {
return err
}
err = updateEdgePolicy(edges, edgeIndex, nodes, edgePolicy)
if err != nil {
return err
}
}
newNumEntries := edgeUpdateIndex.Stats().KeyN
log.Infof("Pruned %d stale entries from the edge update index",
oldNumEntries-newNumEntries)
log.Info("Migration to properly prune edge update index complete!")
return nil
}