// Uses the txid of the target funding transaction and asks blockchain.info's
// api for information (in json) relaated to that transaction.
func lookupTxid(hash *wire.ShaHash) *blockChainInfoTx {
url := "https://blockchain.info/rawtx/" + hash.String()
resp, err := http.Get(url)
if err != nil {
log.Fatal(fmt.Errorf("Tx Lookup failed: %v", err))
}
b, err := ioutil.ReadAll(resp.Body)
if err != nil {
log.Fatal(fmt.Errorf("TxInfo read failed: %s", err))
}
//fmt.Printf("%s\n", b)
txinfo := &blockChainInfoTx{}
err = json.Unmarshal(b, txinfo)
if err != nil {
log.Fatal(err)
}
if txinfo.Ver != 1 {
log.Fatal(fmt.Errorf("Blockchain.info's response seems bad: %v", txinfo))
}
return txinfo
}
// FetchHeightRange looks up a range of blocks by the start and ending
// heights. Fetch is inclusive of the start height and exclusive of the
// ending height. To fetch all hashes from the start height until no
// more are present, use the special id `AllShas'.
func (db *LevelDb) FetchHeightRange(startHeight, endHeight int64) (rshalist []wire.ShaHash, err error) {
db.dbLock.Lock()
defer db.dbLock.Unlock()
var endidx int64
if endHeight == database.AllShas {
endidx = startHeight + 500
} else {
endidx = endHeight
}
shalist := make([]wire.ShaHash, 0, endidx-startHeight)
for height := startHeight; height < endidx; height++ {
// TODO(drahn) fix blkFile from height
key := int64ToKey(height)
blkVal, lerr := db.lDb.Get(key, db.ro)
if lerr != nil {
break
}
var sha wire.ShaHash
sha.SetBytes(blkVal[0:32])
shalist = append(shalist, sha)
}
if err != nil {
return
}
//log.Tracef("FetchIdxRange idx %v %v returned %v shas err %v", startHeight, endHeight, len(shalist), err)
return shalist, nil
}
func parsesha(argstr string) (argtype int, height int64, psha *wire.ShaHash, err error) {
var sha wire.ShaHash
var hashbuf string
switch len(argstr) {
case 64:
hashbuf = argstr
case 66:
if argstr[0:2] != "0x" {
log.Infof("prefix is %v", argstr[0:2])
err = errBadShaPrefix
return
}
hashbuf = argstr[2:]
default:
if len(argstr) <= 16 {
// assume value is height
argtype = argHeight
var h int
h, err = strconv.Atoi(argstr)
if err == nil {
height = int64(h)
return
}
log.Infof("Unable to parse height %v, err %v", height, err)
}
err = errBadShaLen
return
}
var buf [32]byte
for idx, ch := range hashbuf {
var val rune
switch {
case ch >= '0' && ch <= '9':
val = ch - '0'
case ch >= 'a' && ch <= 'f':
val = ch - 'a' + rune(10)
case ch >= 'A' && ch <= 'F':
val = ch - 'A' + rune(10)
default:
err = errBadShaChar
return
}
b := buf[31-idx/2]
if idx&1 == 1 {
b |= byte(val)
} else {
b |= (byte(val) << 4)
}
buf[31-idx/2] = b
}
sha.SetBytes(buf[0:32])
psha = &sha
return
}
// GetBlockAsync returns an instance of a type that can be used to get the
// result of the RPC at some future time by invoking the Receive function on the
// returned instance.
//
// See GetBlock for the blocking version and more details.
func (c *Client) GetBlockAsync(blockHash *wire.ShaHash) FutureGetBlockResult {
hash := ""
if blockHash != nil {
hash = blockHash.String()
}
cmd := btcjson.NewGetBlockCmd(hash, btcjson.Bool(false), nil)
return c.sendCmd(cmd)
}
// GetRawTransactionAsync returns an instance of a type that can be used to get
// the result of the RPC at some future time by invoking the Receive function on
// the returned instance.
//
// See GetRawTransaction for the blocking version and more details.
func (c *Client) GetRawTransactionAsync(txHash *wire.ShaHash) FutureGetRawTransactionResult {
hash := ""
if txHash != nil {
hash = txHash.String()
}
cmd := btcjson.NewGetRawTransactionCmd(hash, btcjson.Int(0))
return c.sendCmd(cmd)
}
// GetTxOutAsync returns an instance of a type that can be used to get
// the result of the RPC at some future time by invoking the Receive function on
// the returned instance.
//
// See GetTxOut for the blocking version and more details.
func (c *Client) GetTxOutAsync(txHash *wire.ShaHash, index uint32, mempool bool) FutureGetTxOutResult {
hash := ""
if txHash != nil {
hash = txHash.String()
}
cmd := btcjson.NewGetTxOutCmd(hash, index, &mempool)
return c.sendCmd(cmd)
}
// GetBlockVerboseAsync returns an instance of a type that can be used to get
// the result of the RPC at some future time by invoking the Receive function on
// the returned instance.
//
// See GetBlockVerbose for the blocking version and more details.
func (c *Client) GetBlockVerboseAsync(blockHash *wire.ShaHash, verboseTx bool) FutureGetBlockVerboseResult {
hash := ""
if blockHash != nil {
hash = blockHash.String()
}
cmd := btcjson.NewGetBlockCmd(hash, btcjson.Bool(true), &verboseTx)
return c.sendCmd(cmd)
}
// add txid of interest
func (t *TxStore) AddTxid(txid *wire.ShaHash, height int32) error {
if txid == nil {
return fmt.Errorf("tried to add nil txid")
}
log.Printf("added %s to OKTxids at height %d\n", txid.String(), height)
t.OKMutex.Lock()
t.OKTxids[*txid] = height
t.OKMutex.Unlock()
return nil
}
// ShaHashToBig converts a wire.ShaHash into a big.Int that can be used to
// perform math comparisons.
func ShaHashToBig(hash *wire.ShaHash) *big.Int {
// A ShaHash is in little-endian, but the big package wants the bytes
// in big-endian. Reverse them. ShaHash.Bytes makes a copy, so it
// is safe to modify the returned buffer.
buf := hash.Bytes()
blen := len(buf)
for i := 0; i < blen/2; i++ {
buf[i], buf[blen-1-i] = buf[blen-1-i], buf[i]
}
return new(big.Int).SetBytes(buf)
}
func assertAddrIndexTipIsUpdated(db database.Db, t *testing.T, newestSha *wire.ShaHash, newestBlockIdx int32) {
// Safe to ignore error, since height will be < 0 in "error" case.
sha, height, _ := db.FetchAddrIndexTip()
if newestBlockIdx != height {
t.Fatalf("Height of address index tip failed to update, "+
"expected %v, got %v", newestBlockIdx, height)
}
if !bytes.Equal(newestSha.Bytes(), sha.Bytes()) {
t.Fatalf("Sha of address index tip failed to update, "+
"expected %v, got %v", newestSha, sha)
}
}
// HashMerkleBranches takes two hashes, treated as the left and right tree
// nodes, and returns the hash of their concatenation. This is a helper
// function used to aid in the generation of a merkle tree.
func HashMerkleBranches(left *wire.ShaHash, right *wire.ShaHash) *wire.ShaHash {
// Concatenate the left and right nodes.
var sha [wire.HashSize * 2]byte
copy(sha[:wire.HashSize], left.Bytes())
copy(sha[wire.HashSize:], right.Bytes())
// Create a new sha hash from the double sha 256. Ignore the error
// here since SetBytes can't fail here due to the fact DoubleSha256
// always returns a []byte of the right size regardless of input.
newSha, _ := wire.NewShaHash(wire.DoubleSha256(sha[:]))
return newSha
}
// fetchBlockShaByHeight returns a block hash based on its height in the
// block chain.
func (db *LevelDb) fetchBlockShaByHeight(height int64) (rsha *wire.ShaHash, err error) {
key := int64ToKey(height)
blkVal, err := db.lDb.Get(key, db.ro)
if err != nil {
log.Tracef("failed to find height %v", height)
return // exists ???
}
var sha wire.ShaHash
sha.SetBytes(blkVal[0:32])
return &sha, nil
}
// blockExists determines whether a block with the given hash exists either in
// the main chain or any side chains.
func (b *BlockChain) blockExists(hash *wire.ShaHash) (bool, error) {
// Check memory chain first (could be main chain or side chain blocks).
if _, ok := b.index[*hash]; ok {
return true, nil
}
// Check if it's the latest checkpoint block
if hash.IsEqual(b.chainParams.Checkpoints[len(b.chainParams.Checkpoints)-1].Hash) {
return true, nil
}
// Check in database (rest of main chain not in memory).
return b.db.ExistsSha(hash)
}
func (db *LevelDb) setBlk(sha *wire.ShaHash, blkHeight int64, buf []byte) {
// serialize
var lw [8]byte
binary.LittleEndian.PutUint64(lw[0:8], uint64(blkHeight))
shaKey := shaBlkToKey(sha)
blkKey := int64ToKey(blkHeight)
shaB := sha.Bytes()
blkVal := make([]byte, len(shaB)+len(buf))
copy(blkVal[0:], shaB)
copy(blkVal[len(shaB):], buf)
db.lBatch().Put(shaKey, lw[:])
db.lBatch().Put(blkKey, blkVal)
}
// fetchAddrIndexTip returns the last block height and block sha to be indexed.
// Meta-data about the address tip is currently cached in memory, and will be
// updated accordingly by functions that modify the state. This function is
// used on start up to load the info into memory. Callers will use the public
// version of this function below, which returns our cached copy.
func (db *LevelDb) fetchAddrIndexTip() (*wire.ShaHash, int64, error) {
db.dbLock.Lock()
defer db.dbLock.Unlock()
data, err := db.lDb.Get(addrIndexMetaDataKey, db.ro)
if err != nil {
return &wire.ShaHash{}, -1, database.ErrAddrIndexDoesNotExist
}
var blkSha wire.ShaHash
blkSha.SetBytes(data[0:32])
blkHeight := binary.LittleEndian.Uint64(data[32:])
return &blkSha, int64(blkHeight), nil
}
// newDummyCredit creates a new credit with the given hash and outpointIdx,
// locked to the votingpool address identified by the given
// series/index/branch.
func newDummyCredit(t *testing.T, pool *Pool, series uint32, index Index, branch Branch,
txSha []byte, outpointIdx uint32) credit {
var hash wire.ShaHash
if err := hash.SetBytes(txSha); err != nil {
t.Fatal(err)
}
// Ensure the address defined by the given series/branch/index is present on
// the set of used addresses as that's a requirement of WithdrawalAddress.
TstEnsureUsedAddr(t, pool, series, branch, index)
addr := TstNewWithdrawalAddress(t, pool, series, branch, index)
c := wtxmgr.Credit{
OutPoint: wire.OutPoint{
Hash: hash,
Index: outpointIdx,
},
}
return newCredit(c, *addr)
}
// GetTx takes a txid and returns the transaction. If we have it.
func (ts *TxStore) GetTx(txid *wire.ShaHash) (*wire.MsgTx, error) {
rtx := wire.NewMsgTx()
err := ts.StateDB.View(func(btx *bolt.Tx) error {
txns := btx.Bucket(BKTTxns)
if txns == nil {
return fmt.Errorf("no transactions in db")
}
txbytes := txns.Get(txid.Bytes())
if txbytes == nil {
return fmt.Errorf("tx %x not in db", txid.String())
}
buf := bytes.NewBuffer(txbytes)
return rtx.Deserialize(buf)
})
if err != nil {
return nil, err
}
return rtx, nil
}
func (db *LevelDb) getBlkByHeight(blkHeight int64) (rsha *wire.ShaHash, rbuf []byte, err error) {
var blkVal []byte
key := int64ToKey(blkHeight)
blkVal, err = db.lDb.Get(key, db.ro)
if err != nil {
log.Tracef("failed to find height %v", blkHeight)
return // exists ???
}
var sha wire.ShaHash
sha.SetBytes(blkVal[0:32])
blockdata := make([]byte, len(blkVal[32:]))
copy(blockdata[:], blkVal[32:])
return &sha, blockdata, nil
}
// RescanEndBlockAsync returns an instance of a type that can be used to get
// the result of the RPC at some future time by invoking the Receive function on
// the returned instance.
//
// See RescanEndBlock for the blocking version and more details.
//
// NOTE: This is a btcd extension and requires a websocket connection.
func (c *Client) RescanEndBlockAsync(startBlock *wire.ShaHash,
addresses []btcutil.Address, outpoints []*wire.OutPoint,
endBlock *wire.ShaHash) FutureRescanResult {
// Not supported in HTTP POST mode.
if c.config.HTTPPostMode {
return newFutureError(ErrNotificationsNotSupported)
}
// Ignore the notification if the client is not interested in
// notifications.
if c.ntfnHandlers == nil {
return newNilFutureResult()
}
// Convert block hashes to strings.
var startBlockShaStr, endBlockShaStr string
if startBlock != nil {
startBlockShaStr = startBlock.String()
}
if endBlock != nil {
endBlockShaStr = endBlock.String()
}
// Convert addresses to strings.
addrs := make([]string, 0, len(addresses))
for _, addr := range addresses {
addrs = append(addrs, addr.String())
}
// Convert outpoints.
ops := make([]btcjson.OutPoint, 0, len(outpoints))
for _, op := range outpoints {
ops = append(ops, newOutPointFromWire(op))
}
cmd := btcjson.NewRescanCmd(startBlockShaStr, addrs, ops,
&endBlockShaStr)
return c.sendCmd(cmd)
}
func (db *LevelDb) getBlkLoc(sha *wire.ShaHash) (int32, error) {
key := shaBlkToKey(sha)
checkpointSha, _ := wire.NewShaHashFromStr("00000000000000000a8dc6ed5b133d0eb2fd6af56203e4159789b092defd8ab2")
if sha.IsEqual(checkpointSha) {
return 382320, nil
}
data, err := db.lDb.Get(key, db.ro)
if err != nil {
if err == leveldb.ErrNotFound {
err = database.ErrBlockShaMissing
}
return 0, err
}
// deserialize
blkHeight := binary.LittleEndian.Uint64(data)
return int32(blkHeight), nil
}
// UpdateAddrIndexForBlock updates the stored addrindex with passed
// index information for a particular block height. Additionally, it
// will update the stored meta-data related to the curent tip of the
// addr index. These two operations are performed in an atomic
// transaction which is commited before the function returns.
// Transactions indexed by address are stored with the following format:
// * prefix || hash160 || blockHeight || txoffset || txlen
// Indexes are stored purely in the key, with blank data for the actual value
// in order to facilitate ease of iteration by their shared prefix and
// also to allow limiting the number of returned transactions (RPC).
// Alternatively, indexes for each address could be stored as an
// append-only list for the stored value. However, this add unnecessary
// overhead when storing and retrieving since the entire list must
// be fetched each time.
func (db *LevelDb) UpdateAddrIndexForBlock(blkSha *wire.ShaHash, blkHeight int64, addrIndex database.BlockAddrIndex) error {
db.dbLock.Lock()
defer db.dbLock.Unlock()
var blankData []byte
batch := db.lBatch()
defer db.lbatch.Reset()
// Write all data for the new address indexes in a single batch
// transaction.
for addrKey, indexes := range addrIndex {
for _, txLoc := range indexes {
index := &txAddrIndex{
hash160: addrKey,
blkHeight: blkHeight,
txoffset: txLoc.TxStart,
txlen: txLoc.TxLen,
}
// The index is stored purely in the key.
packedIndex := addrIndexToKey(index)
batch.Put(packedIndex, blankData)
}
}
// Update tip of addrindex.
newIndexTip := make([]byte, 40, 40)
copy(newIndexTip[:32], blkSha.Bytes())
binary.LittleEndian.PutUint64(newIndexTip[32:], uint64(blkHeight))
batch.Put(addrIndexMetaDataKey, newIndexTip)
if err := db.lDb.Write(batch, db.wo); err != nil {
return err
}
db.lastAddrIndexBlkIdx = blkHeight
db.lastAddrIndexBlkSha = *blkSha
return nil
}
func MakeMerkleParent(left *wire.ShaHash, right *wire.ShaHash) *wire.ShaHash {
// dupes can screw things up; CVE-2012-2459. check for them
if left != nil && right != nil && left.IsEqual(right) {
fmt.Printf("DUP HASH CRASH")
return nil
}
// if left child is nil, output nil. Need this for hard mode.
if left == nil {
return nil
}
// if right is nil, hash left with itself
if right == nil {
right = left
}
// Concatenate the left and right nodes
var sha [64]byte
copy(sha[:32], left[:])
copy(sha[32:], right[:])
newSha := wire.DoubleSha256SH(sha[:])
return &newSha
}
// MakeMerkleParent ...
func MakeMerkleParent(left *wire.ShaHash, right *wire.ShaHash) *wire.ShaHash {
// this can screw things up; CVE-2012-2459
if left != nil && right != nil && left.IsEqual(right) {
fmt.Printf("DUP HASH CRASH")
return nil
}
// if left chils is nil, output nil. Shouldn't need this?
if left == nil {
fmt.Printf("L CRASH")
return nil
}
// if right is nil, has left with itself
if right == nil {
right = left
}
// Concatenate the left and right nodes
var sha [wire.HashSize * 2]byte
copy(sha[:wire.HashSize], left[:])
copy(sha[wire.HashSize:], right[:])
newSha := wire.DoubleSha256SH(sha[:])
return &newSha
}
func testBasicWalletReservationWorkFlow(lnwallet *LightningWallet, t *testing.T) {
// Create our test wallet, will have a total of 20 BTC available for
bobNode, err := newBobNode()
if err != nil {
t.Fatalf("unable to create bob node: %v", err)
}
// Bob initiates a channel funded with 5 BTC for each side, so 10
// BTC total. He also generates 2 BTC in change.
fundingAmount := btcutil.Amount(5 * 1e8)
chanReservation, err := lnwallet.InitChannelReservation(fundingAmount,
SIGHASH, bobNode.id, 4)
if err != nil {
t.Fatalf("unable to initialize funding reservation: %v", err)
}
// The channel reservation should now be populated with a multi-sig key
// from our HD chain, a change output with 3 BTC, and 2 outputs selected
// of 4 BTC each. Additionally, the rest of the items needed to fufill a
// funding contribution should also have been filled in.
ourContribution := chanReservation.OurContribution()
if len(ourContribution.Inputs) != 2 {
t.Fatalf("outputs for funding tx not properly selected, have %v "+
"outputs should have 2", len(ourContribution.Inputs))
}
if ourContribution.ChangeOutputs[0].Value != 3e8 {
t.Fatalf("coin selection failed, change output should be 3e8 "+
"satoshis, is instead %v", ourContribution.ChangeOutputs[0].Value)
}
if ourContribution.MultiSigKey == nil {
t.Fatalf("alice's key for multi-sig not found")
}
if ourContribution.CommitKey == nil {
t.Fatalf("alice's key for commit not found")
}
if ourContribution.DeliveryAddress == nil {
t.Fatalf("alice's final delivery address not found")
}
if bytes.Equal(ourContribution.RevocationHash[:], zeroHash) {
t.Fatalf("alice's revocation hash not found")
}
if ourContribution.CsvDelay == 0 {
t.Fatalf("csv delay not set")
}
// Bob sends over his output, change addr, pub keys, initial revocation,
// final delivery address, and his accepted csv delay for the commitmen
// t transactions.
if err := chanReservation.ProcessContribution(bobNode.Contribution()); err != nil {
t.Fatalf("unable to add bob's funds to the funding tx: %v", err)
}
// At this point, the reservation should have our signatures, and a
// partial funding transaction (missing bob's sigs).
theirContribution := chanReservation.TheirContribution()
ourFundingSigs, ourCommitSig := chanReservation.OurSignatures()
if len(ourFundingSigs) != 2 {
t.Fatalf("only %v of our sigs present, should have 2",
len(ourFundingSigs))
}
if ourCommitSig == nil {
t.Fatalf("commitment sig not found")
}
// Additionally, the funding tx should have been populated.
if chanReservation.partialState.FundingTx == nil {
t.Fatalf("funding transaction never created!")
}
// Their funds should also be filled in.
if len(theirContribution.Inputs) != 1 {
t.Fatalf("bob's outputs for funding tx not properly selected, have %v "+
"outputs should have 2", len(theirContribution.Inputs))
}
if theirContribution.ChangeOutputs[0].Value != 2e8 {
t.Fatalf("bob should have one change output with value 2e8"+
"satoshis, is instead %v",
theirContribution.ChangeOutputs[0].Value)
}
if theirContribution.MultiSigKey == nil {
t.Fatalf("bob's key for multi-sig not found")
}
if theirContribution.CommitKey == nil {
t.Fatalf("bob's key for commit tx not found")
}
if theirContribution.DeliveryAddress == nil {
t.Fatalf("bob's final delivery address not found")
}
if bytes.Equal(theirContribution.RevocationHash[:], zeroHash) {
t.Fatalf("bob's revocaiton hash not found")
}
// Alice responds with her output, change addr, multi-sig key and signatures.
// Bob then responds with his signatures.
bobsSigs, err := bobNode.signFundingTx(chanReservation.partialState.FundingTx)
if err != nil {
t.Fatalf("unable to sign inputs for bob: %v", err)
}
commitSig, err := bobNode.signCommitTx(
chanReservation.partialState.OurCommitTx,
chanReservation.partialState.FundingRedeemScript)
if err != nil {
t.Fatalf("bob is unable to sign alice's commit tx: %v", err)
}
if err := chanReservation.CompleteReservation(bobsSigs, commitSig); err != nil {
t.Fatalf("unable to complete funding tx: %v", err)
}
// At this point, the channel can be considered "open" when the funding
// txn hits a "comfortable" depth.
fundingTx := chanReservation.FinalFundingTx()
// The resulting active channel state should have been persisted to the DB.
channel, err := lnwallet.ChannelDB.FetchOpenChannel(bobNode.id)
if err != nil {
t.Fatalf("unable to retrieve channel from DB: %v", err)
}
if channel.FundingTx.TxSha() != fundingTx.TxSha() {
t.Fatalf("channel state not properly saved")
}
// The funding tx should now be valid and complete.
// Check each input and ensure all scripts are fully valid.
// TODO(roasbeef): remove this loop after nodetest hooked up.
var zeroHash wire.ShaHash
for i, input := range fundingTx.TxIn {
var pkscript []byte
// Bob's txin
if bytes.Equal(input.PreviousOutPoint.Hash.Bytes(),
zeroHash.Bytes()) {
pkscript = bobNode.changeOutputs[0].PkScript
} else {
// Does the wallet know about the txin?
txDetail, err := lnwallet.TxStore.TxDetails(&input.PreviousOutPoint.Hash)
if txDetail == nil || err != nil {
t.Fatalf("txstore can't find tx detail, err: %v", err)
}
prevIndex := input.PreviousOutPoint.Index
pkscript = txDetail.TxRecord.MsgTx.TxOut[prevIndex].PkScript
}
vm, err := txscript.NewEngine(pkscript,
fundingTx, i, txscript.StandardVerifyFlags, nil)
if err != nil {
// TODO(roasbeef): cancel at this stage if invalid sigs?
t.Fatalf("cannot create script engine: %s", err)
}
if err = vm.Execute(); err != nil {
t.Fatalf("cannot validate transaction: %s", err)
}
}
}
// RightSha ...
func RightSha(in wire.ShaHash) wire.ShaHash {
return wire.DoubleSha256SH(append(in.Bytes(), 0x01)) // sha(sha(in, 1))
}
// LeftSha ...
func LeftSha(in wire.ShaHash) wire.ShaHash {
return wire.DoubleSha256SH(in.Bytes()) // left is sha(sha(in))
}
// blockLocatorFromHash returns a block locator for the passed block hash.
// See BlockLocator for details on the algotirhm used to create a block locator.
//
// In addition to the general algorithm referenced above, there are a couple of
// special cases which are handled:
//
// - If the genesis hash is passed, there are no previous hashes to add and
// therefore the block locator will only consist of the genesis hash
// - If the passed hash is not currently known, the block locator will only
// consist of the passed hash
//
// This function MUST be called with the chain state lock held (for reads).
func (b *BlockChain) blockLocatorFromHash(hash *wire.ShaHash) BlockLocator {
// The locator contains the requested hash at the very least.
locator := make(BlockLocator, 0, wire.MaxBlockLocatorsPerMsg)
locator = append(locator, hash)
// Nothing more to do if a locator for the genesis hash was requested.
if hash.IsEqual(b.chainParams.GenesisHash) {
return locator
}
// Attempt to find the height of the block that corresponds to the
// passed hash, and if it's on a side chain, also find the height at
// which it forks from the main chain.
blockHeight := int32(-1)
forkHeight := int32(-1)
node, exists := b.index[*hash]
if !exists {
// Try to look up the height for passed block hash. Assume an
// error means it doesn't exist and just return the locator for
// the block itself.
var height int32
err := b.db.View(func(dbTx database.Tx) error {
var err error
height, err = dbFetchHeightByHash(dbTx, hash)
return err
})
if err != nil {
return locator
}
blockHeight = height
} else {
blockHeight = node.height
// Find the height at which this node forks from the main chain
// if the node is on a side chain.
if !node.inMainChain {
for n := node; n.parent != nil; n = n.parent {
if n.inMainChain {
forkHeight = n.height
break
}
}
}
}
// Generate the block locators according to the algorithm described in
// in the BlockLocator comment and make sure to leave room for the final
// genesis hash.
//
// The error is intentionally ignored here since the only way the code
// could fail is if there is something wrong with the database which
// will be caught in short order anyways and it's also safe to ignore
// block locators.
_ = b.db.View(func(dbTx database.Tx) error {
iterNode := node
increment := int32(1)
for len(locator) < wire.MaxBlockLocatorsPerMsg-1 {
// Once there are 10 locators, exponentially increase
// the distance between each block locator.
if len(locator) > 10 {
increment *= 2
}
blockHeight -= increment
if blockHeight < 1 {
break
}
// As long as this is still on the side chain, walk
// backwards along the side chain nodes to each block
// height.
if forkHeight != -1 && blockHeight > forkHeight {
// Intentionally use parent field instead of the
// getPrevNodeFromNode function since we don't
// want to dynamically load nodes when building
// block locators. Side chain blocks should
// always be in memory already, and if they
// aren't for some reason it's ok to skip them.
for iterNode != nil && blockHeight > iterNode.height {
iterNode = iterNode.parent
}
if iterNode != nil && iterNode.height == blockHeight {
locator = append(locator, iterNode.hash)
}
continue
}
// The desired block height is in the main chain, so
// look it up from the main chain database.
h, err := dbFetchHashByHeight(dbTx, blockHeight)
if err != nil {
// This shouldn't happen and it's ok to ignore
// block locators, so just continue to the next
// one.
log.Warnf("Lookup of known valid height failed %v",
blockHeight)
continue
}
locator = append(locator, h)
}
return nil
})
// Append the appropriate genesis block.
locator = append(locator, b.chainParams.GenesisHash)
return locator
}
func shaBlkToKey(sha *wire.ShaHash) []byte {
shaB := sha.Bytes()
return shaB
}
func shaSpentTxToKey(sha *wire.ShaHash) []byte {
shaB := sha.Bytes()
shaB = append(shaB, "sx"...)
return shaB
}
func toHash(txHash *wire.ShaHash) *common.Hash {
h := new(common.Hash)
h.SetBytes(txHash.Bytes())
return h
}