lbcwallet/wallet/chainntfns.go
Bjarne Magnussen 419381b749
wallet: call InsertTxCheckIfExists to add a relevant tx
Let the method `addRelevantTx` use `InsertTxCheckIfExists` to insert a relevant 
transaction. If the transaction has already been recorded, the method call 
`addRelevantTx` will return early and not proceed with duplicating work of 
checking every output and duplicating the tx notification to the notification 
server.
2021-07-13 09:24:53 +02:00

493 lines
15 KiB
Go

// Copyright (c) 2013-2015 The btcsuite developers
// Use of this source code is governed by an ISC
// license that can be found in the LICENSE file.
package wallet
import (
"bytes"
"fmt"
"time"
"github.com/btcsuite/btcd/chaincfg/chainhash"
"github.com/btcsuite/btcd/txscript"
"github.com/btcsuite/btcd/wire"
"github.com/btcsuite/btcwallet/chain"
"github.com/btcsuite/btcwallet/waddrmgr"
"github.com/btcsuite/btcwallet/walletdb"
"github.com/btcsuite/btcwallet/wtxmgr"
)
const (
// birthdayBlockDelta is the maximum time delta allowed between our
// birthday timestamp and our birthday block's timestamp when searching
// for a better birthday block candidate (if possible).
birthdayBlockDelta = 2 * time.Hour
)
func (w *Wallet) handleChainNotifications() {
defer w.wg.Done()
chainClient, err := w.requireChainClient()
if err != nil {
log.Errorf("handleChainNotifications called without RPC client")
return
}
catchUpHashes := func(w *Wallet, client chain.Interface,
height int32) error {
// TODO(aakselrod): There's a race condition here, which
// happens when a reorg occurs between the
// rescanProgress notification and the last GetBlockHash
// call. The solution when using btcd is to make btcd
// send blockconnected notifications with each block
// the way Neutrino does, and get rid of the loop. The
// other alternative is to check the final hash and,
// if it doesn't match the original hash returned by
// the notification, to roll back and restart the
// rescan.
log.Infof("Catching up block hashes to height %d, this"+
" might take a while", height)
err := walletdb.Update(w.db, func(tx walletdb.ReadWriteTx) error {
ns := tx.ReadWriteBucket(waddrmgrNamespaceKey)
startBlock := w.Manager.SyncedTo()
for i := startBlock.Height + 1; i <= height; i++ {
hash, err := client.GetBlockHash(int64(i))
if err != nil {
return err
}
header, err := chainClient.GetBlockHeader(hash)
if err != nil {
return err
}
bs := waddrmgr.BlockStamp{
Height: i,
Hash: *hash,
Timestamp: header.Timestamp,
}
err = w.Manager.SetSyncedTo(ns, &bs)
if err != nil {
return err
}
}
return nil
})
if err != nil {
log.Errorf("Failed to update address manager "+
"sync state for height %d: %v", height, err)
}
log.Info("Done catching up block hashes")
return err
}
for {
select {
case n, ok := <-chainClient.Notifications():
if !ok {
return
}
var notificationName string
var err error
switch n := n.(type) {
case chain.ClientConnected:
// Before attempting to sync with our backend,
// we'll make sure that our birthday block has
// been set correctly to potentially prevent
// missing relevant events.
birthdayStore := &walletBirthdayStore{
db: w.db,
manager: w.Manager,
}
birthdayBlock, err := birthdaySanityCheck(
chainClient, birthdayStore,
)
if err != nil && !waddrmgr.IsError(err, waddrmgr.ErrBirthdayBlockNotSet) {
panic(fmt.Errorf("unable to sanity "+
"check wallet birthday block: %v",
err))
}
err = w.syncWithChain(birthdayBlock)
if err != nil && !w.ShuttingDown() {
panic(fmt.Errorf("unable to synchronize "+
"wallet to chain: %v", err))
}
case chain.BlockConnected:
err = walletdb.Update(w.db, func(tx walletdb.ReadWriteTx) error {
return w.connectBlock(tx, wtxmgr.BlockMeta(n))
})
notificationName = "block connected"
case chain.BlockDisconnected:
err = walletdb.Update(w.db, func(tx walletdb.ReadWriteTx) error {
return w.disconnectBlock(tx, wtxmgr.BlockMeta(n))
})
notificationName = "block disconnected"
case chain.RelevantTx:
err = walletdb.Update(w.db, func(tx walletdb.ReadWriteTx) error {
return w.addRelevantTx(tx, n.TxRecord, n.Block)
})
notificationName = "relevant transaction"
case chain.FilteredBlockConnected:
// Atomically update for the whole block.
if len(n.RelevantTxs) > 0 {
err = walletdb.Update(w.db, func(
tx walletdb.ReadWriteTx) error {
var err error
for _, rec := range n.RelevantTxs {
err = w.addRelevantTx(tx, rec,
n.Block)
if err != nil {
return err
}
}
return nil
})
}
notificationName = "filtered block connected"
// The following require some database maintenance, but also
// need to be reported to the wallet's rescan goroutine.
case *chain.RescanProgress:
err = catchUpHashes(w, chainClient, n.Height)
notificationName = "rescan progress"
select {
case w.rescanNotifications <- n:
case <-w.quitChan():
return
}
case *chain.RescanFinished:
err = catchUpHashes(w, chainClient, n.Height)
notificationName = "rescan finished"
w.SetChainSynced(true)
select {
case w.rescanNotifications <- n:
case <-w.quitChan():
return
}
}
if err != nil {
// If we received a block connected notification
// while rescanning, then we can ignore logging
// the error as we'll properly catch up once we
// process the RescanFinished notification.
if notificationName == "block connected" &&
waddrmgr.IsError(err, waddrmgr.ErrBlockNotFound) &&
!w.ChainSynced() {
log.Debugf("Received block connected "+
"notification for height %v "+
"while rescanning",
n.(chain.BlockConnected).Height)
continue
}
log.Errorf("Unable to process chain backend "+
"%v notification: %v", notificationName,
err)
}
case <-w.quit:
return
}
}
}
// connectBlock handles a chain server notification by marking a wallet
// that's currently in-sync with the chain server as being synced up to
// the passed block.
func (w *Wallet) connectBlock(dbtx walletdb.ReadWriteTx, b wtxmgr.BlockMeta) error {
addrmgrNs := dbtx.ReadWriteBucket(waddrmgrNamespaceKey)
bs := waddrmgr.BlockStamp{
Height: b.Height,
Hash: b.Hash,
Timestamp: b.Time,
}
err := w.Manager.SetSyncedTo(addrmgrNs, &bs)
if err != nil {
return err
}
// Notify interested clients of the connected block.
//
// TODO: move all notifications outside of the database transaction.
w.NtfnServer.notifyAttachedBlock(dbtx, &b)
return nil
}
// disconnectBlock handles a chain server reorganize by rolling back all
// block history from the reorged block for a wallet in-sync with the chain
// server.
func (w *Wallet) disconnectBlock(dbtx walletdb.ReadWriteTx, b wtxmgr.BlockMeta) error {
addrmgrNs := dbtx.ReadWriteBucket(waddrmgrNamespaceKey)
txmgrNs := dbtx.ReadWriteBucket(wtxmgrNamespaceKey)
if !w.ChainSynced() {
return nil
}
// Disconnect the removed block and all blocks after it if we know about
// the disconnected block. Otherwise, the block is in the future.
if b.Height <= w.Manager.SyncedTo().Height {
hash, err := w.Manager.BlockHash(addrmgrNs, b.Height)
if err != nil {
return err
}
if bytes.Equal(hash[:], b.Hash[:]) {
bs := waddrmgr.BlockStamp{
Height: b.Height - 1,
}
hash, err = w.Manager.BlockHash(addrmgrNs, bs.Height)
if err != nil {
return err
}
b.Hash = *hash
client := w.ChainClient()
header, err := client.GetBlockHeader(hash)
if err != nil {
return err
}
bs.Timestamp = header.Timestamp
err = w.Manager.SetSyncedTo(addrmgrNs, &bs)
if err != nil {
return err
}
err = w.TxStore.Rollback(txmgrNs, b.Height)
if err != nil {
return err
}
}
}
// Notify interested clients of the disconnected block.
w.NtfnServer.notifyDetachedBlock(&b.Hash)
return nil
}
func (w *Wallet) addRelevantTx(dbtx walletdb.ReadWriteTx, rec *wtxmgr.TxRecord, block *wtxmgr.BlockMeta) error {
addrmgrNs := dbtx.ReadWriteBucket(waddrmgrNamespaceKey)
txmgrNs := dbtx.ReadWriteBucket(wtxmgrNamespaceKey)
// At the moment all notified transactions are assumed to actually be
// relevant. This assumption will not hold true when SPV support is
// added, but until then, simply insert the transaction because there
// should either be one or more relevant inputs or outputs.
exists, err := w.TxStore.InsertTxCheckIfExists(txmgrNs, rec, block)
if err != nil {
return err
}
// If the transaction has already been recorded, we can return early.
// Note: Returning here is safe as we're within the context of an atomic
// database transaction, so we don't need to worry about the MarkUsed
// calls below.
if exists {
return nil
}
// Check every output to determine whether it is controlled by a wallet
// key. If so, mark the output as a credit.
for i, output := range rec.MsgTx.TxOut {
_, addrs, _, err := txscript.ExtractPkScriptAddrs(output.PkScript,
w.chainParams)
if err != nil {
// Non-standard outputs are skipped.
continue
}
for _, addr := range addrs {
ma, err := w.Manager.Address(addrmgrNs, addr)
if err == nil {
// TODO: Credits should be added with the
// account they belong to, so wtxmgr is able to
// track per-account balances.
err = w.TxStore.AddCredit(txmgrNs, rec, block, uint32(i),
ma.Internal())
if err != nil {
return err
}
err = w.Manager.MarkUsed(addrmgrNs, addr)
if err != nil {
return err
}
log.Debugf("Marked address %v used", addr)
continue
}
// Missing addresses are skipped. Other errors should
// be propagated.
if !waddrmgr.IsError(err, waddrmgr.ErrAddressNotFound) {
return err
}
}
}
// Send notification of mined or unmined transaction to any interested
// clients.
//
// TODO: Avoid the extra db hits.
if block == nil {
details, err := w.TxStore.UniqueTxDetails(txmgrNs, &rec.Hash, nil)
if err != nil {
log.Errorf("Cannot query transaction details for notification: %v", err)
}
// It's possible that the transaction was not found within the
// wallet's set of unconfirmed transactions due to it already
// being confirmed, so we'll avoid notifying it.
//
// TODO(wilmer): ideally we should find the culprit to why we're
// receiving an additional unconfirmed chain.RelevantTx
// notification from the chain backend.
if details != nil {
w.NtfnServer.notifyUnminedTransaction(dbtx, details)
}
} else {
details, err := w.TxStore.UniqueTxDetails(txmgrNs, &rec.Hash, &block.Block)
if err != nil {
log.Errorf("Cannot query transaction details for notification: %v", err)
}
// We'll only notify the transaction if it was found within the
// wallet's set of confirmed transactions.
if details != nil {
w.NtfnServer.notifyMinedTransaction(dbtx, details, block)
}
}
return nil
}
// chainConn is an interface that abstracts the chain connection logic required
// to perform a wallet's birthday block sanity check.
type chainConn interface {
// GetBestBlock returns the hash and height of the best block known to
// the backend.
GetBestBlock() (*chainhash.Hash, int32, error)
// GetBlockHash returns the hash of the block with the given height.
GetBlockHash(int64) (*chainhash.Hash, error)
// GetBlockHeader returns the header for the block with the given hash.
GetBlockHeader(*chainhash.Hash) (*wire.BlockHeader, error)
}
// birthdayStore is an interface that abstracts the wallet's sync-related
// information required to perform a birthday block sanity check.
type birthdayStore interface {
// Birthday returns the birthday timestamp of the wallet.
Birthday() time.Time
// BirthdayBlock returns the birthday block of the wallet. The boolean
// returned should signal whether the wallet has already verified the
// correctness of its birthday block.
BirthdayBlock() (waddrmgr.BlockStamp, bool, error)
// SetBirthdayBlock updates the birthday block of the wallet to the
// given block. The boolean can be used to signal whether this block
// should be sanity checked the next time the wallet starts.
//
// NOTE: This should also set the wallet's synced tip to reflect the new
// birthday block. This will allow the wallet to rescan from this point
// to detect any potentially missed events.
SetBirthdayBlock(waddrmgr.BlockStamp) error
}
// walletBirthdayStore is a wrapper around the wallet's database and address
// manager that satisfies the birthdayStore interface.
type walletBirthdayStore struct {
db walletdb.DB
manager *waddrmgr.Manager
}
var _ birthdayStore = (*walletBirthdayStore)(nil)
// Birthday returns the birthday timestamp of the wallet.
func (s *walletBirthdayStore) Birthday() time.Time {
return s.manager.Birthday()
}
// BirthdayBlock returns the birthday block of the wallet.
func (s *walletBirthdayStore) BirthdayBlock() (waddrmgr.BlockStamp, bool, error) {
var (
birthdayBlock waddrmgr.BlockStamp
birthdayBlockVerified bool
)
err := walletdb.View(s.db, func(tx walletdb.ReadTx) error {
var err error
ns := tx.ReadBucket(waddrmgrNamespaceKey)
birthdayBlock, birthdayBlockVerified, err = s.manager.BirthdayBlock(ns)
return err
})
return birthdayBlock, birthdayBlockVerified, err
}
// SetBirthdayBlock updates the birthday block of the wallet to the
// given block. The boolean can be used to signal whether this block
// should be sanity checked the next time the wallet starts.
//
// NOTE: This should also set the wallet's synced tip to reflect the new
// birthday block. This will allow the wallet to rescan from this point
// to detect any potentially missed events.
func (s *walletBirthdayStore) SetBirthdayBlock(block waddrmgr.BlockStamp) error {
return walletdb.Update(s.db, func(tx walletdb.ReadWriteTx) error {
ns := tx.ReadWriteBucket(waddrmgrNamespaceKey)
err := s.manager.SetBirthdayBlock(ns, block, true)
if err != nil {
return err
}
return s.manager.SetSyncedTo(ns, &block)
})
}
// birthdaySanityCheck is a helper function that ensures a birthday block
// correctly reflects the birthday timestamp within a reasonable timestamp
// delta. It's intended to be run after the wallet establishes its connection
// with the backend, but before it begins syncing. This is done as the second
// part to the wallet's address manager migration where we populate the birthday
// block to ensure we do not miss any relevant events throughout rescans.
// waddrmgr.ErrBirthdayBlockNotSet is returned if the birthday block has not
// been set yet.
func birthdaySanityCheck(chainConn chainConn,
birthdayStore birthdayStore) (*waddrmgr.BlockStamp, error) {
// We'll start by fetching our wallet's birthday timestamp and block.
birthdayTimestamp := birthdayStore.Birthday()
birthdayBlock, birthdayBlockVerified, err := birthdayStore.BirthdayBlock()
if err != nil {
return nil, err
}
// If the birthday block has already been verified to be correct, we can
// exit our sanity check to prevent potentially fetching a better
// candidate.
if birthdayBlockVerified {
log.Debugf("Birthday block has already been verified: "+
"height=%d, hash=%v", birthdayBlock.Height,
birthdayBlock.Hash)
return &birthdayBlock, nil
}
// Otherwise, we'll attempt to locate a better one now that we have
// access to the chain.
newBirthdayBlock, err := locateBirthdayBlock(chainConn, birthdayTimestamp)
if err != nil {
return nil, err
}
if err := birthdayStore.SetBirthdayBlock(*newBirthdayBlock); err != nil {
return nil, err
}
return newBirthdayBlock, nil
}