// Copyright 2015 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package eth
import (
"fmt"
"math"
"math/big"
"sync"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/eth/downloader"
"github.com/ethereum/go-ethereum/eth/fetcher"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/event"
"github.com/ethereum/go-ethereum/logger"
"github.com/ethereum/go-ethereum/logger/glog"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/pow"
"github.com/ethereum/go-ethereum/rlp"
)
const (
softResponseLimit = 2 * 1024 * 1024 // Target maximum size of returned blocks, headers or node data.
estHeaderRlpSize = 500 // Approximate size of an RLP encoded block header
)
func errResp(code errCode, format string, v ...interface{}) error {
return fmt.Errorf("%v - %v", code, fmt.Sprintf(format, v...))
}
type hashFetcherFn func(common.Hash) error
type blockFetcherFn func([]common.Hash) error
// extProt is an interface which is passed around so we can expose GetHashes and GetBlock without exposing it to the rest of the protocol
// extProt is passed around to peers which require to GetHashes and GetBlocks
type extProt struct {
getHashes hashFetcherFn
getBlocks blockFetcherFn
}
func (ep extProt) GetHashes(hash common.Hash) error { return ep.getHashes(hash) }
func (ep extProt) GetBlock(hashes []common.Hash) error { return ep.getBlocks(hashes) }
type ProtocolManager struct {
txpool txPool
chainman *core.ChainManager
chaindb ethdb.Database
downloader *downloader.Downloader
fetcher *fetcher.Fetcher
peers *peerSet
SubProtocols []p2p.Protocol
eventMux *event.TypeMux
txSub event.Subscription
minedBlockSub event.Subscription
// channels for fetcher, syncer, txsyncLoop
newPeerCh chan *peer
txsyncCh chan *txsync
quitSync chan struct{}
// wait group is used for graceful shutdowns during downloading
// and processing
wg sync.WaitGroup
quit bool
}
// NewProtocolManager returns a new ethereum sub protocol manager. The Ethereum sub protocol manages peers capable
// with the ethereum network.
func NewProtocolManager(networkId int, mux *event.TypeMux, txpool txPool, pow pow.PoW, chainman *core.ChainManager, chaindb ethdb.Database) *ProtocolManager {
// Create the protocol manager with the base fields
manager := &ProtocolManager{
eventMux: mux,
txpool: txpool,
chainman: chainman,
chaindb: chaindb,
peers: newPeerSet(),
newPeerCh: make(chan *peer, 1),
txsyncCh: make(chan *txsync),
quitSync: make(chan struct{}),
}
// Initiate a sub-protocol for every implemented version we can handle
manager.SubProtocols = make([]p2p.Protocol, len(ProtocolVersions))
for i := 0; i < len(manager.SubProtocols); i++ {
version := ProtocolVersions[i]
manager.SubProtocols[i] = p2p.Protocol{
Name: "eth",
Version: version,
Length: ProtocolLengths[i],
Run: func(p *p2p.Peer, rw p2p.MsgReadWriter) error {
peer := manager.newPeer(int(version), networkId, p, rw)
manager.newPeerCh <- peer
return manager.handle(peer)
},
}
}
// Construct the different synchronisation mechanisms
manager.downloader = downloader.New(manager.eventMux, manager.chainman.HasBlock, manager.chainman.GetBlock, manager.chainman.CurrentBlock, manager.chainman.GetTd, manager.chainman.InsertChain, manager.removePeer)
validator := func(block *types.Block, parent *types.Block) error {
return core.ValidateHeader(pow, block.Header(), parent, true, false)
}
heighter := func() uint64 {
return manager.chainman.CurrentBlock().NumberU64()
}
manager.fetcher = fetcher.New(manager.chainman.GetBlock, validator, manager.BroadcastBlock, heighter, manager.chainman.InsertChain, manager.removePeer)
return manager
}
func (pm *ProtocolManager) removePeer(id string) {
// Short circuit if the peer was already removed
peer := pm.peers.Peer(id)
if peer == nil {
return
}
glog.V(logger.Debug).Infoln("Removing peer", id)
// Unregister the peer from the downloader and Ethereum peer set
pm.downloader.UnregisterPeer(id)
if err := pm.peers.Unregister(id); err != nil {
glog.V(logger.Error).Infoln("Removal failed:", err)
}
// Hard disconnect at the networking layer
if peer != nil {
peer.Peer.Disconnect(p2p.DiscUselessPeer)
}
}
func (pm *ProtocolManager) Start() {
// broadcast transactions
pm.txSub = pm.eventMux.Subscribe(core.TxPreEvent{})
go pm.txBroadcastLoop()
// broadcast mined blocks
pm.minedBlockSub = pm.eventMux.Subscribe(core.NewMinedBlockEvent{})
go pm.minedBroadcastLoop()
// start sync handlers
go pm.syncer()
go pm.txsyncLoop()
}
func (pm *ProtocolManager) Stop() {
// Showing a log message. During download / process this could actually
// take between 5 to 10 seconds and therefor feedback is required.
glog.V(logger.Info).Infoln("Stopping ethereum protocol handler...")
pm.quit = true
pm.txSub.Unsubscribe() // quits txBroadcastLoop
pm.minedBlockSub.Unsubscribe() // quits blockBroadcastLoop
close(pm.quitSync) // quits syncer, fetcher, txsyncLoop
// Wait for any process action
pm.wg.Wait()
glog.V(logger.Info).Infoln("Ethereum protocol handler stopped")
}
func (pm *ProtocolManager) newPeer(pv, nv int, p *p2p.Peer, rw p2p.MsgReadWriter) *peer {
return newPeer(pv, nv, p, newMeteredMsgWriter(rw))
}
// handle is the callback invoked to manage the life cycle of an eth peer. When
// this function terminates, the peer is disconnected.
func (pm *ProtocolManager) handle(p *peer) error {
glog.V(logger.Debug).Infof("%v: peer connected [%s]", p, p.Name())
// Execute the Ethereum handshake
td, head, genesis := pm.chainman.Status()
if err := p.Handshake(td, head, genesis); err != nil {
glog.V(logger.Debug).Infof("%v: handshake failed: %v", p, err)
return err
}
if rw, ok := p.rw.(*meteredMsgReadWriter); ok {
rw.Init(p.version)
}
// Register the peer locally
glog.V(logger.Detail).Infof("%v: adding peer", p)
if err := pm.peers.Register(p); err != nil {
glog.V(logger.Error).Infof("%v: addition failed: %v", p, err)
return err
}
defer pm.removePeer(p.id)
// Register the peer in the downloader. If the downloader considers it banned, we disconnect
if err := pm.downloader.RegisterPeer(p.id, p.version, p.Head(),
p.RequestHashes, p.RequestHashesFromNumber, p.RequestBlocks,
p.RequestHeadersByHash, p.RequestHeadersByNumber, p.RequestBodies); err != nil {
return err
}
// Propagate existing transactions. new transactions appearing
// after this will be sent via broadcasts.
pm.syncTransactions(p)
// main loop. handle incoming messages.
for {
if err := pm.handleMsg(p); err != nil {
glog.V(logger.Debug).Infof("%v: message handling failed: %v", p, err)
return err
}
}
return nil
}
// handleMsg is invoked whenever an inbound message is received from a remote
// peer. The remote connection is torn down upon returning any error.
func (pm *ProtocolManager) handleMsg(p *peer) error {
// Read the next message from the remote peer, and ensure it's fully consumed
msg, err := p.rw.ReadMsg()
if err != nil {
return err
}
if msg.Size > ProtocolMaxMsgSize {
return errResp(ErrMsgTooLarge, "%v > %v", msg.Size, ProtocolMaxMsgSize)
}
defer msg.Discard()
// Handle the message depending on its contents
switch {
case msg.Code == StatusMsg:
// Status messages should never arrive after the handshake
return errResp(ErrExtraStatusMsg, "uncontrolled status message")
case p.version < eth62 && msg.Code == GetBlockHashesMsg:
// Retrieve the number of hashes to return and from which origin hash
var request getBlockHashesData
if err := msg.Decode(&request); err != nil {
return errResp(ErrDecode, "%v: %v", msg, err)
}
if request.Amount > uint64(downloader.MaxHashFetch) {
request.Amount = uint64(downloader.MaxHashFetch)
}
// Retrieve the hashes from the block chain and return them
hashes := pm.chainman.GetBlockHashesFromHash(request.Hash, request.Amount)
if len(hashes) == 0 {
glog.V(logger.Debug).Infof("invalid block hash %x", request.Hash.Bytes()[:4])
}
return p.SendBlockHashes(hashes)
case p.version < eth62 && msg.Code == GetBlockHashesFromNumberMsg:
// Retrieve and decode the number of hashes to return and from which origin number
var request getBlockHashesFromNumberData
if err := msg.Decode(&request); err != nil {
return errResp(ErrDecode, "%v: %v", msg, err)
}
if request.Amount > uint64(downloader.MaxHashFetch) {
request.Amount = uint64(downloader.MaxHashFetch)
}
// Calculate the last block that should be retrieved, and short circuit if unavailable
last := pm.chainman.GetBlockByNumber(request.Number + request.Amount - 1)
if last == nil {
last = pm.chainman.CurrentBlock()
request.Amount = last.NumberU64() - request.Number + 1
}
if last.NumberU64() < request.Number {
return p.SendBlockHashes(nil)
}
// Retrieve the hashes from the last block backwards, reverse and return
hashes := []common.Hash{last.Hash()}
hashes = append(hashes, pm.chainman.GetBlockHashesFromHash(last.Hash(), request.Amount-1)...)
for i := 0; i < len(hashes)/2; i++ {
hashes[i], hashes[len(hashes)-1-i] = hashes[len(hashes)-1-i], hashes[i]
}
return p.SendBlockHashes(hashes)
case p.version < eth62 && msg.Code == BlockHashesMsg:
// A batch of hashes arrived to one of our previous requests
var hashes []common.Hash
if err := msg.Decode(&hashes); err != nil {
break
}
// Deliver them all to the downloader for queuing
err := pm.downloader.DeliverHashes61(p.id, hashes)
if err != nil {
glog.V(logger.Debug).Infoln(err)
}
case p.version < eth62 && msg.Code == GetBlocksMsg:
// Decode the retrieval message
msgStream := rlp.NewStream(msg.Payload, uint64(msg.Size))
if _, err := msgStream.List(); err != nil {
return err
}
// Gather blocks until the fetch or network limits is reached
var (
hash common.Hash
bytes common.StorageSize
blocks []*types.Block
)
for len(blocks) < downloader.MaxBlockFetch && bytes < softResponseLimit {
//Retrieve the hash of the next block
err := msgStream.Decode(&hash)
if err == rlp.EOL {
break
} else if err != nil {
return errResp(ErrDecode, "msg %v: %v", msg, err)
}
// Retrieve the requested block, stopping if enough was found
if block := pm.chainman.GetBlock(hash); block != nil {
blocks = append(blocks, block)
bytes += block.Size()
}
}
return p.SendBlocks(blocks)
case p.version < eth62 && msg.Code == BlocksMsg:
// Decode the arrived block message
var blocks []*types.Block
if err := msg.Decode(&blocks); err != nil {
glog.V(logger.Detail).Infoln("Decode error", err)
blocks = nil
}
// Update the receive timestamp of each block
for _, block := range blocks {
block.ReceivedAt = msg.ReceivedAt
}
// Filter out any explicitly requested blocks, deliver the rest to the downloader
if blocks := pm.fetcher.FilterBlocks(blocks); len(blocks) > 0 {
pm.downloader.DeliverBlocks61(p.id, blocks)
}
// Block header query, collect the requested headers and reply
case p.version >= eth62 && msg.Code == GetBlockHeadersMsg:
// Decode the complex header query
var query getBlockHeadersData
if err := msg.Decode(&query); err != nil {
return errResp(ErrDecode, "%v: %v", msg, err)
}
// Gather headers until the fetch or network limits is reached
var (
bytes common.StorageSize
headers []*types.Header
unknown bool
)
for !unknown && len(headers) < int(query.Amount) && bytes < softResponseLimit && len(headers) < downloader.MaxHeaderFetch {
// Retrieve the next header satisfying the query
var origin *types.Header
if query.Origin.Hash != (common.Hash{}) {
origin = pm.chainman.GetHeader(query.Origin.Hash)
} else {
origin = pm.chainman.GetHeaderByNumber(query.Origin.Number)
}
if origin == nil {
break
}
headers = append(headers, origin)
bytes += estHeaderRlpSize
// Advance to the next header of the query
switch {
case query.Origin.Hash != (common.Hash{}) && query.Reverse:
// Hash based traversal towards the genesis block
for i := 0; i < int(query.Skip)+1; i++ {
if header := pm.chainman.GetHeader(query.Origin.Hash); header != nil {
query.Origin.Hash = header.ParentHash
} else {
unknown = true
break
}
}
case query.Origin.Hash != (common.Hash{}) && !query.Reverse:
// Hash based traversal towards the leaf block
if header := pm.chainman.GetHeaderByNumber(origin.Number.Uint64() + query.Skip + 1); header != nil {
if pm.chainman.GetBlockHashesFromHash(header.Hash(), query.Skip+1)[query.Skip] == query.Origin.Hash {
query.Origin.Hash = header.Hash()
} else {
unknown = true
}
} else {
unknown = true
}
case query.Reverse:
// Number based traversal towards the genesis block
if query.Origin.Number >= query.Skip+1 {
query.Origin.Number -= (query.Skip + 1)
} else {
unknown = true
}
case !query.Reverse:
// Number based traversal towards the leaf block
query.Origin.Number += (query.Skip + 1)
}
}
return p.SendBlockHeaders(headers)
case p.version >= eth62 && msg.Code == BlockHeadersMsg:
// A batch of headers arrived to one of our previous requests
var headers []*types.Header
if err := msg.Decode(&headers); err != nil {
return errResp(ErrDecode, "msg %v: %v", msg, err)
}
// Filter out any explicitly requested headers, deliver the rest to the downloader
filter := len(headers) == 1
if filter {
headers = pm.fetcher.FilterHeaders(headers, time.Now())
}
if len(headers) > 0 || !filter {
err := pm.downloader.DeliverHeaders(p.id, headers)
if err != nil {
glog.V(logger.Debug).Infoln(err)
}
}
case p.version >= eth62 && msg.Code == BlockBodiesMsg:
// A batch of block bodies arrived to one of our previous requests
var request blockBodiesData
if err := msg.Decode(&request); err != nil {
return errResp(ErrDecode, "msg %v: %v", msg, err)
}
// Deliver them all to the downloader for queuing
trasactions := make([][]*types.Transaction, len(request))
uncles := make([][]*types.Header, len(request))
for i, body := range request {
trasactions[i] = body.Transactions
uncles[i] = body.Uncles
}
// Filter out any explicitly requested bodies, deliver the rest to the downloader
if trasactions, uncles := pm.fetcher.FilterBodies(trasactions, uncles, time.Now()); len(trasactions) > 0 || len(uncles) > 0 {
err := pm.downloader.DeliverBodies(p.id, trasactions, uncles)
if err != nil {
glog.V(logger.Debug).Infoln(err)
}
}
case p.version >= eth62 && msg.Code == GetBlockBodiesMsg:
// Decode the retrieval message
msgStream := rlp.NewStream(msg.Payload, uint64(msg.Size))
if _, err := msgStream.List(); err != nil {
return err
}
// Gather blocks until the fetch or network limits is reached
var (
hash common.Hash
bytes int
bodies []rlp.RawValue
)
for bytes < softResponseLimit && len(bodies) < downloader.MaxBlockFetch {
// Retrieve the hash of the next block
if err := msgStream.Decode(&hash); err == rlp.EOL {
break
} else if err != nil {
return errResp(ErrDecode, "msg %v: %v", msg, err)
}
// Retrieve the requested block body, stopping if enough was found
if data := pm.chainman.GetBodyRLP(hash); len(data) != 0 {
bodies = append(bodies, data)
bytes += len(data)
}
}
return p.SendBlockBodiesRLP(bodies)
case p.version >= eth63 && msg.Code == GetNodeDataMsg:
// Decode the retrieval message
msgStream := rlp.NewStream(msg.Payload, uint64(msg.Size))
if _, err := msgStream.List(); err != nil {
return err
}
// Gather state data until the fetch or network limits is reached
var (
hash common.Hash
bytes int
data [][]byte
)
for bytes < softResponseLimit && len(data) < downloader.MaxStateFetch {
// Retrieve the hash of the next state entry
if err := msgStream.Decode(&hash); err == rlp.EOL {
break
} else if err != nil {
return errResp(ErrDecode, "msg %v: %v", msg, err)
}
// Retrieve the requested state entry, stopping if enough was found
if entry, err := pm.chaindb.Get(hash.Bytes()); err == nil {
data = append(data, entry)
bytes += len(entry)
}
}
return p.SendNodeData(data)
case p.version >= eth63 && msg.Code == GetReceiptsMsg:
// Decode the retrieval message
msgStream := rlp.NewStream(msg.Payload, uint64(msg.Size))
if _, err := msgStream.List(); err != nil {
return err
}
// Gather state data until the fetch or network limits is reached
var (
hash common.Hash
bytes int
receipts []*types.Receipt
)
for bytes < softResponseLimit && len(receipts) < downloader.MaxReceiptsFetch {
// Retrieve the hash of the next transaction receipt
if err := msgStream.Decode(&hash); err == rlp.EOL {
break
} else if err != nil {
return errResp(ErrDecode, "msg %v: %v", msg, err)
}
// Retrieve the requested receipt, stopping if enough was found
if receipt := core.GetReceipt(pm.chaindb, hash); receipt != nil {
receipts = append(receipts, receipt)
bytes += len(receipt.RlpEncode())
}
}
return p.SendReceipts(receipts)
case msg.Code == NewBlockHashesMsg:
// Retrieve and deseralize the remote new block hashes notification
type announce struct {
Hash common.Hash
Number uint64
}
var announces = []announce{}
if p.version < eth62 {
// We're running the old protocol, make block number unknown (0)
var hashes []common.Hash
if err := msg.Decode(&hashes); err != nil {
return errResp(ErrDecode, "%v: %v", msg, err)
}
for _, hash := range hashes {
announces = append(announces, announce{hash, 0})
}
} else {
// Otherwise extract both block hash and number
var request newBlockHashesData
if err := msg.Decode(&request); err != nil {
return errResp(ErrDecode, "%v: %v", msg, err)
}
for _, block := range request {
announces = append(announces, announce{block.Hash, block.Number})
}
}
// Mark the hashes as present at the remote node
for _, block := range announces {
p.MarkBlock(block.Hash)
p.SetHead(block.Hash)
}
// Schedule all the unknown hashes for retrieval
unknown := make([]announce, 0, len(announces))
for _, block := range announces {
if !pm.chainman.HasBlock(block.Hash) {
unknown = append(unknown, block)
}
}
for _, block := range unknown {
if p.version < eth62 {
pm.fetcher.Notify(p.id, block.Hash, block.Number, time.Now(), p.RequestBlocks, nil, nil)
} else {
pm.fetcher.Notify(p.id, block.Hash, block.Number, time.Now(), nil, p.RequestOneHeader, p.RequestBodies)
}
}
case msg.Code == NewBlockMsg:
// Retrieve and decode the propagated block
var request newBlockData
if err := msg.Decode(&request); err != nil {
return errResp(ErrDecode, "%v: %v", msg, err)
}
if err := request.Block.ValidateFields(); err != nil {
return errResp(ErrDecode, "block validation %v: %v", msg, err)
}
request.Block.ReceivedAt = msg.ReceivedAt
// Mark the block's arrival for whatever reason
_, chainHead, _ := pm.chainman.Status()
jsonlogger.LogJson(&logger.EthChainReceivedNewBlock{
BlockHash: request.Block.Hash().Hex(),
BlockNumber: request.Block.Number(),
ChainHeadHash: chainHead.Hex(),
BlockPrevHash: request.Block.ParentHash().Hex(),
RemoteId: p.ID().String(),
})
// Mark the peer as owning the block and schedule it for import
p.MarkBlock(request.Block.Hash())
p.SetHead(request.Block.Hash())
pm.fetcher.Enqueue(p.id, request.Block)
// Update the peers total difficulty if needed, schedule a download if gapped
if request.TD.Cmp(p.Td()) > 0 {
p.SetTd(request.TD)
if request.TD.Cmp(new(big.Int).Add(pm.chainman.Td(), request.Block.Difficulty())) > 0 {
go pm.synchronise(p)
}
}
case msg.Code == TxMsg:
// Transactions arrived, parse all of them and deliver to the pool
var txs []*types.Transaction
if err := msg.Decode(&txs); err != nil {
return errResp(ErrDecode, "msg %v: %v", msg, err)
}
for i, tx := range txs {
// Validate and mark the remote transaction
if tx == nil {
return errResp(ErrDecode, "transaction %d is nil", i)
}
p.MarkTransaction(tx.Hash())
// Log it's arrival for later analysis
jsonlogger.LogJson(&logger.EthTxReceived{
TxHash: tx.Hash().Hex(),
RemoteId: p.ID().String(),
})
}
pm.txpool.AddTransactions(txs)
default:
return errResp(ErrInvalidMsgCode, "%v", msg.Code)
}
return nil
}
// BroadcastBlock will either propagate a block to a subset of it's peers, or
// will only announce it's availability (depending what's requested).
func (pm *ProtocolManager) BroadcastBlock(block *types.Block, propagate bool) {
hash := block.Hash()
peers := pm.peers.PeersWithoutBlock(hash)
// If propagation is requested, send to a subset of the peer
if propagate {
// Calculate the TD of the block (it's not imported yet, so block.Td is not valid)
var td *big.Int
if parent := pm.chainman.GetBlock(block.ParentHash()); parent != nil {
td = new(big.Int).Add(block.Difficulty(), pm.chainman.GetTd(block.ParentHash()))
} else {
glog.V(logger.Error).Infof("propagating dangling block #%d [%x]", block.NumberU64(), hash[:4])
return
}
// Send the block to a subset of our peers
transfer := peers[:int(math.Sqrt(float64(len(peers))))]
for _, peer := range transfer {
peer.SendNewBlock(block, td)
}
glog.V(logger.Detail).Infof("propagated block %x to %d peers in %v", hash[:4], len(transfer), time.Since(block.ReceivedAt))
}
// Otherwise if the block is indeed in out own chain, announce it
if pm.chainman.HasBlock(hash) {
for _, peer := range peers {
if peer.version < eth62 {
peer.SendNewBlockHashes61([]common.Hash{hash})
} else {
peer.SendNewBlockHashes([]common.Hash{hash}, []uint64{block.NumberU64()})
}
}
glog.V(logger.Detail).Infof("announced block %x to %d peers in %v", hash[:4], len(peers), time.Since(block.ReceivedAt))
}
}
// BroadcastTx will propagate a transaction to all peers which are not known to
// already have the given transaction.
func (pm *ProtocolManager) BroadcastTx(hash common.Hash, tx *types.Transaction) {
// Broadcast transaction to a batch of peers not knowing about it
peers := pm.peers.PeersWithoutTx(hash)
//FIXME include this again: peers = peers[:int(math.Sqrt(float64(len(peers))))]
for _, peer := range peers {
peer.SendTransactions(types.Transactions{tx})
}
glog.V(logger.Detail).Infoln("broadcast tx to", len(peers), "peers")
}
// Mined broadcast loop
func (self *ProtocolManager) minedBroadcastLoop() {
// automatically stops if unsubscribe
for obj := range self.minedBlockSub.Chan() {
switch ev := obj.(type) {
case core.NewMinedBlockEvent:
self.BroadcastBlock(ev.Block, true) // First propagate block to peers
self.BroadcastBlock(ev.Block, false) // Only then announce to the rest
}
}
}
func (self *ProtocolManager) txBroadcastLoop() {
// automatically stops if unsubscribe
for obj := range self.txSub.Chan() {
event := obj.(core.TxPreEvent)
self.BroadcastTx(event.Tx.Hash(), event.Tx)
}
}