wallet: remove sync.go, references decred

This commit is contained in:
Olaoluwa Osuntokun 2017-04-21 16:28:45 -07:00
parent bf86ccf5b4
commit 14e6fe36d0

View file

@ -1,710 +0,0 @@
//+build ignore
/*
* Copyright (c) 2013-2016 The btcsuite developers
* Copyright (c) 2015 The Decred developers
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
package wallet
import (
"bytes"
"encoding/hex"
"fmt"
"strconv"
"github.com/btcsuite/btclog"
"github.com/decred/bitset"
"github.com/decred/dcrutil"
"github.com/decred/dcrwallet/chain"
"github.com/decred/dcrwallet/waddrmgr"
"github.com/decred/dcrwallet/walletdb"
)
// finalScanLength is the final length of accounts to scan for the
// function below.
var finalAcctScanLength = 50
// acctSeekWidth is the number of addresses for both internal and external
// branches to scan to determine whether or not an account exists and should
// be rescanned. This is the tolerance for account gaps as well.
var acctSeekWidth uint32 = 5
// accountIsUsed checks if an account has ever been used by scanning the
// first acctSeekWidth many addresses for usage.
func (w *Wallet) accountIsUsed(account uint32, chainClient *chain.RPCClient) bool {
// Search external branch then internal branch for a used
// address. We need to set the address function to use based
// on whether or not this is the initial sync. The function
// AddressDerivedFromCointype is able to see addresses that
// exists in accounts that have not yet been created, while
// AddressDerivedFromDbAcct can not.
addrFunc := w.Manager.AddressDerivedFromDbAcct
if w.initiallyUnlocked {
addrFunc = w.Manager.AddressDerivedFromCointype
}
for branch := uint32(0); branch < 2; branch++ {
for i := uint32(0); i < acctSeekWidth; i++ {
var addr dcrutil.Address
err := walletdb.View(w.db, func(tx walletdb.ReadTx) error {
addrmgrNs := tx.ReadBucket(waddrmgrNamespaceKey)
var err error
addr, err = addrFunc(addrmgrNs, i, account, branch)
return err
})
if err != nil {
// Skip erroneous keys, which happen rarely.
continue
}
exists, err := chainClient.ExistsAddress(addr)
if err != nil {
return false
}
if exists {
return true
}
}
}
return false
}
// bisectLastAcctIndex is a helper function for searching through accounts to
// find the last used account. It uses logarithmic scanning to determine if
// an account has been used.
func (w *Wallet) bisectLastAcctIndex(hi, low int) int {
chainClient, err := w.requireChainClient()
if err != nil {
return 0
}
offset := low
for i := hi - low - 1; i > 0; i /= 2 {
if i+offset+int(acctSeekWidth) < waddrmgr.MaxAddressesPerAccount {
for j := i + offset + int(addrSeekWidth); j >= i+offset; j-- {
if w.accountIsUsed(uint32(j), chainClient) {
return i + offset
}
}
} else {
if w.accountIsUsed(uint32(i+offset), chainClient) {
return i + offset
}
}
}
return 0
}
// findAcctEnd is a helper function for searching for the last used account by
// logarithmic scanning of the account indexes.
func (w *Wallet) findAcctEnd(start, stop int) int {
indexStart := w.bisectLastAcctIndex(stop, start)
indexLast := 0
for {
indexLastStored := indexStart
low := indexLastStored
hi := indexLast + ((indexStart - indexLast) * 2) + 1
indexStart = w.bisectLastAcctIndex(hi, low)
indexLast = indexLastStored
if indexStart == 0 {
break
}
}
return indexLast
}
// scanAccountIndex identifies the last used address in an HD keychain of public
// keys. It returns the index of the last used key, along with the address of
// this key.
func (w *Wallet) scanAccountIndex(start int, end int) (uint32, error) {
chainClient, err := w.requireChainClient()
if err != nil {
return 0, err
}
// Find the last used account. Scan from it to the end in case there was a
// gap from that position, which is possible. Then, return the account
// in that position.
lastUsed := w.findAcctEnd(start, end)
if lastUsed != 0 {
for i := lastUsed + finalAcctScanLength; i >= lastUsed; i-- {
if w.accountIsUsed(uint32(i), chainClient) {
return uint32(i), nil
}
}
}
// We can't find any used addresses. The account is
// unused.
return 0, nil
}
// debugScanLength is the final length of keys to scan past the
// last index returned from the logarithmic scanning function
// when creating the debug string of used addresses.
var debugAddrScanLength = 3500
// addrSeekWidth is the number of new addresses to generate and add to the
// address manager when trying to sync up a wallet to the main chain. This
// is the maximum gap introduced by a resyncing as well, and should be less
// than finalScanLength above.
// TODO Optimize the scanning so that rather than overshooting the end address,
// you instead step through addresses incrementally until reaching idx so that
// you don't reach a gap. This can be done by keeping track of where the current
// cursor is and adding addresses in big chunks until you hit the end.
var addrSeekWidth uint32 = 20
// errDerivation is an error type signifying that the waddrmgr failed to
// derive a key.
var errDerivation = fmt.Errorf("failed to derive key")
// scanAddressRange scans backwards from end to start many addresses in the
// account branch, and return the first index that is found on the blockchain.
// If the address doesn't exist, false is returned as the first argument.
func (w *Wallet) scanAddressRange(account uint32, branch uint32, start int,
end int, chainClient *chain.RPCClient) (bool, int, error) {
var addresses []dcrutil.Address
err := walletdb.View(w.db, func(tx walletdb.ReadTx) error {
addrmgrNs := tx.ReadBucket(waddrmgrNamespaceKey)
var err error
addresses, err = w.Manager.AddressesDerivedFromDbAcct(addrmgrNs,
uint32(start), uint32(end+1), account, branch)
if err != nil {
return errDerivation
}
return nil
})
if err != nil {
return false, 0, err
}
// Whether or not the addresses exist is encoded as a binary
// bitset.
exists, err := chainClient.ExistsAddresses(addresses)
if err != nil {
return false, 0, err
}
existsB, err := hex.DecodeString(exists)
if err != nil {
return false, 0, err
}
set := bitset.Bytes(existsB)
// Prevent a panic when an empty message is passed as a response.
if len(set) == 0 {
return false, 0, nil
}
// Scan backwards and return if we find an address exists.
idx := end
itr := len(addresses) - 1
for idx >= start {
// If the address exists in the mempool or blockchain according
// to the bit set returned, return this index.
if set.Get(itr) {
return true, idx, nil
}
itr--
idx--
}
return false, 0, nil
}
// bisectLastAddrIndex is a helper function for search through addresses.
func (w *Wallet) bisectLastAddrIndex(hi, low int, account uint32, branch uint32) int {
chainClient, err := w.requireChainClient()
if err != nil {
return 0
}
// Logarithmically scan address indexes to find the last used
// address index. Each time the algorithm receives an end point,
// scans a chunk of addresses at the end point, and if no
// addresses are found, divides the address index by two and
// repeats until it finds the last used index.
offset := low
for i := hi - low - 1; i > 0; i /= 2 {
if i+offset+int(addrSeekWidth) < waddrmgr.MaxAddressesPerAccount {
start := i + offset
end := i + offset + int(addrSeekWidth)
exists, idx, err := w.scanAddressRange(account, branch, start, end,
chainClient)
// Skip erroneous keys, which happen rarely. Don't skip
// other errors.
if err == errDerivation {
continue
}
if err != nil {
log.Warnf("unexpected error encountered during bisection "+
"scan of account %v, branch %v: %s", account, branch,
err.Error())
return 0
}
if exists {
return idx
}
} else {
var addr dcrutil.Address
err := walletdb.View(w.db, func(tx walletdb.ReadTx) error {
addrmgrNs := tx.ReadBucket(waddrmgrNamespaceKey)
var err error
addr, err = w.Manager.AddressDerivedFromDbAcct(addrmgrNs,
uint32(i+offset), account, branch)
return err
})
// Skip erroneous keys, which happen rarely.
if err != nil {
continue
}
exists, err := chainClient.ExistsAddress(addr)
if err != nil {
return 0
}
if exists {
return i + offset
}
}
}
return 0
}
// findEnd is a helper function for searching for used addresses.
func (w *Wallet) findAddrEnd(start, stop int, account uint32, branch uint32) int {
indexStart := w.bisectLastAddrIndex(stop, start, account, branch)
indexLast := 0
for {
indexLastStored := indexStart
low := indexLastStored
hi := indexLast + ((indexStart - indexLast) * 2) + 1
indexStart = w.bisectLastAddrIndex(hi, low, account, branch)
indexLast = indexLastStored
if indexStart == 0 {
break
}
}
return indexLast
}
// debugAccountAddrGapsString is a debug function that prints a graphical outlook
// of address usage to a string, from the perspective of the daemon.
func debugAccountAddrGapsString(scanBackFrom int, account uint32, branch uint32,
w *Wallet) (string, error) {
chainClient, err := w.requireChainClient()
if err != nil {
return "", err
}
var buf bytes.Buffer
str := fmt.Sprintf("Begin debug address scan scanning backwards from "+
"idx %v, account %v, branch %v\n", scanBackFrom, account, branch)
buf.WriteString(str)
firstUsedIndex := 0
for i := scanBackFrom; i > 0; i-- {
var addr dcrutil.Address
err := walletdb.View(w.db, func(tx walletdb.ReadTx) error {
addrmgrNs := tx.ReadBucket(waddrmgrNamespaceKey)
var err error
addr, err = w.Manager.AddressDerivedFromDbAcct(addrmgrNs,
uint32(i), account, branch)
return err
})
// Skip erroneous keys.
if err != nil {
continue
}
exists, err := chainClient.ExistsAddress(addr)
if err != nil {
return "", fmt.Errorf("failed to access chain server: %v",
err.Error())
}
if exists {
firstUsedIndex = i
break
}
}
str = fmt.Sprintf("Last used index found: %v\n", firstUsedIndex)
buf.WriteString(str)
batchSize := 50
batches := (firstUsedIndex / batchSize) + 1
lastBatchSize := 0
if firstUsedIndex%batchSize != 0 {
lastBatchSize = firstUsedIndex - ((batches - 1) * batchSize)
}
for i := 0; i < batches; i++ {
str = fmt.Sprintf("%8v", i*batchSize)
buf.WriteString(str)
start := i * batchSize
end := (i + 1) * batchSize
if i == batches-1 {
// Nothing to do because last batch empty.
if lastBatchSize == 0 {
break
}
end = (i*batchSize + lastBatchSize) + 1
}
for j := start; j < end; j++ {
if j%10 == 0 {
buf.WriteString(" ")
}
char := "_"
var addr dcrutil.Address
err := walletdb.View(w.db, func(tx walletdb.ReadTx) error {
addrmgrNs := tx.ReadBucket(waddrmgrNamespaceKey)
var err error
addr, err = w.Manager.AddressDerivedFromDbAcct(addrmgrNs,
uint32(j), account, branch)
return err
})
if err != nil {
char = "X"
}
exists, err := chainClient.ExistsAddress(addr)
if err != nil {
return "", fmt.Errorf("failed to access chain server: %v",
err.Error())
}
if exists {
char = "#"
}
buf.WriteString(char)
}
buf.WriteString("\n")
}
return buf.String(), nil
}
// scanAddressIndex identifies the last used address in an HD keychain of public
// keys. It returns the index of the last used key, along with the address of
// this key.
func (w *Wallet) scanAddressIndex(start int, end int, account uint32,
branch uint32) (uint32, dcrutil.Address, error) {
chainClient, err := w.requireChainClient()
if err != nil {
return 0, nil, err
}
// Find the last used address. Scan from it to the end in case there was a
// gap from that position, which is possible. Then, return the address
// in that position.
lastUsed := w.findAddrEnd(start, end, account, branch)
// If debug is on, do an exhaustive check and a graphical printout
// of what the used addresses currently look like.
if log.Level() == btclog.DebugLvl || log.Level() == btclog.TraceLvl {
dbgStr, err := debugAccountAddrGapsString(lastUsed+debugAddrScanLength,
account, branch, w)
if err != nil {
log.Debugf("Failed to debug address gaps for account %v, "+
"branch %v: %v", account, branch, err)
} else {
log.Debugf("%v", dbgStr)
}
}
// If there was a last used index, do an exhaustive final scan that
// reexamines the last used addresses and ensures that the final index
// we have found is correct.
if lastUsed != 0 {
start := lastUsed
end := lastUsed + w.addrIdxScanLen
exists, idx, err := w.scanAddressRange(account, branch, start, end,
chainClient)
if err != nil {
return 0, nil, err
}
if exists {
lastUsed = idx
var addr dcrutil.Address
err := walletdb.View(w.db, func(tx walletdb.ReadTx) error {
addrmgrNs := tx.ReadBucket(waddrmgrNamespaceKey)
var err error
addr, err = w.Manager.AddressDerivedFromDbAcct(addrmgrNs,
uint32(lastUsed), account, branch)
return err
})
if err != nil {
return 0, nil, err
}
return uint32(lastUsed), addr, nil
}
}
// In the case that 0 was returned as the last used address,
// make sure the the 0th address was not used. If it was,
// return this address to let the caller know that this
// 0th address was used.
if lastUsed == 0 {
var addr dcrutil.Address
err := walletdb.View(w.db, func(tx walletdb.ReadTx) error {
addrmgrNs := tx.ReadBucket(waddrmgrNamespaceKey)
var err error
addr, err = w.Manager.AddressDerivedFromDbAcct(addrmgrNs, 0,
account, branch)
return err
})
// Skip erroneous keys.
if err != nil {
return 0, nil, err
}
exists, err := chainClient.ExistsAddress(addr)
if err != nil {
return 0, nil, fmt.Errorf("failed to access chain server: %v",
err.Error())
}
if exists {
return 0, addr, nil
}
}
// We can't find any used addresses for this account's
// branch.
return 0, nil, nil
}
// rescanActiveAddresses accesses the daemon to discover all the addresses that
// have been used by an HD keychain stemming from this wallet in the default
// account.
func (w *Wallet) rescanActiveAddresses() error {
log.Infof("Beginning a rescan of active addresses using the daemon. " +
"This may take a while.")
// Start by rescanning the accounts and determining what the
// current account index is. This scan should only ever be
// performed if we're restoring our wallet from seed.
lastAcct := uint32(0)
var err error
if w.initiallyUnlocked {
min := 0
max := waddrmgr.MaxAccountNum
lastAcct, err = w.scanAccountIndex(min, max)
if err != nil {
return err
}
}
err = walletdb.Update(w.db, func(tx walletdb.ReadWriteTx) error {
addrmgrNs := tx.ReadWriteBucket(waddrmgrNamespaceKey)
lastAcctMgr, err := w.Manager.LastAccount(addrmgrNs)
if err != nil {
return err
}
// The address manager is not synced (wallet has been restored
// from seed?). In this case, spawn the accounts in the address
// manager first. The accounts are named by their respective
// index number, as strings.
if lastAcctMgr < lastAcct {
for i := lastAcctMgr + 1; i <= lastAcct; i++ {
_, err := w.Manager.NewAccount(
addrmgrNs, strconv.Itoa(int(i)))
if err != nil {
return err
}
}
}
// The account manager has a greater index than the rescan.
// It is likely that the end user created a new account but
// did not use it yet. Rescan it anyway so that the address
// pool is created.
if lastAcctMgr > lastAcct {
lastAcct = lastAcctMgr
}
return nil
})
if err != nil {
return err
}
log.Infof("The last used account was %v. Beginning a rescan for "+
"all active addresses in known accounts.", lastAcct)
// Rescan addresses for the both the internal and external
// branches of the account. Insert a new address pool for
// the respective account and initialize it.
for acct := uint32(0); acct <= lastAcct; acct++ {
var extIdx, intIdx uint32
min := 0
max := waddrmgr.MaxAddressesPerAccount
// Do this for both external (0) and internal (1) branches.
for branch := uint32(0); branch < 2; branch++ {
idx, lastAddr, err := w.scanAddressIndex(min, max, acct, branch)
if err != nil {
return err
}
err = walletdb.Update(w.db, func(tx walletdb.ReadWriteTx) error {
addrmgrNs := tx.ReadWriteBucket(waddrmgrNamespaceKey)
// If the account is unused, buffer the initial address pool
// by syncing the address manager upstream.
unusedAcct := (lastAddr == nil)
if unusedAcct {
_, err := w.Manager.SyncAccountToAddrIndex(
addrmgrNs, acct, addressPoolBuffer, branch)
if err != nil {
// A ErrSyncToIndex error indicates that we're already
// synced to beyond the end of the account in the
// waddrmgr.
errWaddrmgr, ok := err.(waddrmgr.ManagerError)
if !ok || errWaddrmgr.ErrorCode != waddrmgr.ErrSyncToIndex {
return fmt.Errorf("failed to create initial waddrmgr "+
"address buffer for the address pool, "+
"account %v, branch %v: %s", acct, branch,
err.Error())
}
}
}
branchString := "external"
if branch == waddrmgr.InternalBranch {
branchString = "internal"
}
// Fetch the address pool index for this account and
// branch from the database meta bucket.
isInternal := branch == waddrmgr.InternalBranch
oldIdx, err := w.Manager.NextToUseAddrPoolIndex(
addrmgrNs, isInternal, acct)
unexpectedError := false
if err != nil {
mErr, ok := err.(waddrmgr.ManagerError)
if !ok {
unexpectedError = true
} else {
// Skip errors where the account's address index
// has not been store. For this case, oldIdx will
// be the special case 0 which will always be
// skipped in the initialization step below.
if mErr.ErrorCode != waddrmgr.ErrMetaPoolIdxNoExist {
unexpectedError = true
}
}
if unexpectedError {
return fmt.Errorf("got unexpected error trying to "+
"retrieve last known addr index for acct %v, "+
"%s branch: %v", acct, branchString, err)
}
}
// If the stored index is further along than the sync-to
// index determined by the contents of daemon's addrindex,
// use it to initialize the address pool instead.
nextToUseIdx := idx
if !unusedAcct {
nextToUseIdx++
}
if oldIdx > nextToUseIdx {
nextToUseIdx = oldIdx
}
nextToUseAddr, err := w.Manager.AddressDerivedFromDbAcct(
addrmgrNs, nextToUseIdx, acct, branch)
if err != nil {
return fmt.Errorf("failed to derive next address for "+
"account %v, branch %v: %s", acct, branch,
err.Error())
}
// Save these for the address pool startup later.
if isInternal {
intIdx = nextToUseIdx
} else {
extIdx = nextToUseIdx
}
// Synchronize the account manager to our address index plus
// an extra chunk of addresses that are used as a buffer
// in the address pool.
_, err = w.Manager.SyncAccountToAddrIndex(addrmgrNs,
acct, nextToUseIdx+addressPoolBuffer, branch)
if err != nil {
// A ErrSyncToIndex error indicates that we're already
// synced to beyond the end of the account in the
// waddrmgr.
errWaddrmgr, ok := err.(waddrmgr.ManagerError)
if !ok || errWaddrmgr.ErrorCode != waddrmgr.ErrSyncToIndex {
return fmt.Errorf("couldn't sync %s addresses in "+
"address manager: %v", branchString, err.Error())
}
}
// Set the next address in the waddrmgr database so that the
// address pool can synchronize properly after.
err = w.Manager.StoreNextToUseAddress(
addrmgrNs, isInternal, acct, nextToUseIdx)
if err != nil {
log.Errorf("Failed to store next to use pool idx for "+
"%s pool in the manager on init sync: %v",
branchString, err.Error())
}
log.Infof("Successfully synchronized the address manager to "+
"%s address %v (key index %v) for account %v",
branchString,
nextToUseAddr.String(),
nextToUseIdx,
acct)
return nil
})
if err != nil {
return err
}
}
pool, err := newAddressPools(acct, intIdx, extIdx, w)
if err != nil {
return err
}
w.addrPoolsMtx.Lock()
w.addrPools[acct] = pool
w.addrPoolsMtx.Unlock()
}
log.Infof("Successfully synchronized wallet accounts to account "+
"number %v.", lastAcct)
return nil
}