// 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 dex
import (
"encoding/json"
"errors"
"fmt"
"math"
"math/big"
"sync"
"sync/atomic"
"time"
"github.com/dexon-foundation/dexon/common"
"github.com/dexon-foundation/dexon/consensus"
"github.com/dexon-foundation/dexon/consensus/misc"
"github.com/dexon-foundation/dexon/core"
"github.com/dexon-foundation/dexon/core/types"
"github.com/dexon-foundation/dexon/eth/downloader"
"github.com/dexon-foundation/dexon/eth/fetcher"
"github.com/dexon-foundation/dexon/ethdb"
"github.com/dexon-foundation/dexon/event"
"github.com/dexon-foundation/dexon/log"
"github.com/dexon-foundation/dexon/p2p"
"github.com/dexon-foundation/dexon/p2p/enode"
"github.com/dexon-foundation/dexon/params"
"github.com/dexon-foundation/dexon/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
// txChanSize is the size of channel listening to NewTxsEvent.
// The number is referenced from the size of tx pool.
txChanSize = 4096
metaChanSize = 10240
)
var (
daoChallengeTimeout = 15 * time.Second // Time allowance for a node to reply to the DAO handshake challenge
)
// errIncompatibleConfig is returned if the requested protocols and configs are
// not compatible (low protocol version restrictions and high requirements).
var errIncompatibleConfig = errors.New("incompatible configuration")
func errResp(code errCode, format string, v ...interface{}) error {
return fmt.Errorf("%v - %v", code, fmt.Sprintf(format, v...))
}
type ProtocolManager struct {
networkID uint64
fastSync uint32 // Flag whether fast sync is enabled (gets disabled if we already have blocks)
acceptTxs uint32 // Flag whether we're considered synchronised (enables transaction processing)
txpool txPool
nodeTable *nodeTable
gov governance
blockchain *core.BlockChain
chainconfig *params.ChainConfig
maxPeers int
downloader *downloader.Downloader
fetcher *fetcher.Fetcher
peers *peerSet
SubProtocols []p2p.Protocol
eventMux *event.TypeMux
txsCh chan core.NewTxsEvent
txsSub event.Subscription
metasCh chan newMetasEvent
metasSub event.Subscription
minedBlockSub *event.TypeMuxSubscription
// channels for fetcher, syncer, txsyncLoop
newPeerCh chan *peer
txsyncCh chan *txsync
metasyncCh chan *metasync
quitSync chan struct{}
noMorePeers chan struct{}
// channels for peerSetLoop
crsCh chan core.NewCRSEvent
crsSub event.Subscription
srvr p2pServer
// wait group is used for graceful shutdowns during downloading
// and processing
wg sync.WaitGroup
}
// NewProtocolManager returns a new Ethereum sub protocol manager. The Ethereum sub protocol manages peers capable
// with the Ethereum network.
func NewProtocolManager(
config *params.ChainConfig, mode downloader.SyncMode, networkID uint64,
mux *event.TypeMux, txpool txPool, engine consensus.Engine,
blockchain *core.BlockChain, chaindb ethdb.Database,
gov governance) (*ProtocolManager, error) {
tab := newNodeTable()
// Create the protocol manager with the base fields
manager := &ProtocolManager{
networkID: networkID,
eventMux: mux,
txpool: txpool,
nodeTable: tab,
gov: gov,
blockchain: blockchain,
chainconfig: config,
newPeerCh: make(chan *peer),
noMorePeers: make(chan struct{}),
txsyncCh: make(chan *txsync),
quitSync: make(chan struct{}),
}
// Figure out whether to allow fast sync or not
if mode == downloader.FastSync && blockchain.CurrentBlock().NumberU64() > 0 {
log.Warn("Blockchain not empty, fast sync disabled")
mode = downloader.FullSync
}
if mode == downloader.FastSync {
manager.fastSync = uint32(1)
}
// Initiate a sub-protocol for every implemented version we can handle
manager.SubProtocols = make([]p2p.Protocol, 0, len(ProtocolVersions))
for i, version := range ProtocolVersions {
version := version // Closure for the run
manager.SubProtocols = append(manager.SubProtocols, p2p.Protocol{
Name: ProtocolName,
Version: version,
Length: ProtocolLengths[i],
Run: func(p *p2p.Peer, rw p2p.MsgReadWriter) error {
peer := manager.newPeer(int(version), p, rw)
select {
case manager.newPeerCh <- peer:
manager.wg.Add(1)
defer manager.wg.Done()
return manager.handle(peer)
case <-manager.quitSync:
return p2p.DiscQuitting
}
},
NodeInfo: func() interface{} {
return manager.NodeInfo()
},
PeerInfo: func(id enode.ID) interface{} {
if p := manager.peers.Peer(fmt.Sprintf("%x", id[:8])); p != nil {
return p.Info()
}
return nil
},
})
}
if len(manager.SubProtocols) == 0 {
return nil, errIncompatibleConfig
}
// Construct the different synchronisation mechanisms
manager.downloader = downloader.New(mode, chaindb, manager.eventMux, blockchain, nil, manager.removePeer)
validator := func(header *types.Header) error {
return engine.VerifyHeader(blockchain, header, true)
}
heighter := func() uint64 {
return blockchain.CurrentBlock().NumberU64()
}
inserter := func(blocks types.Blocks) (int, error) {
// If fast sync is running, deny importing weird blocks
if atomic.LoadUint32(&manager.fastSync) == 1 {
log.Warn("Discarded bad propagated block", "number", blocks[0].Number(), "hash", blocks[0].Hash())
return 0, nil
}
atomic.StoreUint32(&manager.acceptTxs, 1) // Mark initial sync done on any fetcher import
return manager.blockchain.InsertChain(blocks)
}
manager.fetcher = fetcher.New(blockchain.GetBlockByHash, validator, manager.BroadcastBlock, heighter, inserter, manager.removePeer)
return manager, nil
}
func (pm *ProtocolManager) removePeer(id string) {
// Short circuit if the peer was already removed
peer := pm.peers.Peer(id)
if peer == nil {
return
}
log.Debug("Removing Ethereum peer", "peer", id)
// Unregister the peer from the downloader and Ethereum peer set
pm.downloader.UnregisterPeer(id)
if err := pm.peers.Unregister(id); err != nil {
log.Error("Peer removal failed", "peer", id, "err", err)
}
// Hard disconnect at the networking layer
if peer != nil {
peer.Peer.Disconnect(p2p.DiscUselessPeer)
}
}
func (pm *ProtocolManager) Start(srvr p2pServer, maxPeers int) {
pm.maxPeers = maxPeers
pm.srvr = srvr
pm.peers = newPeerSet(pm.gov, pm.srvr, pm.nodeTable)
// if our self in node set build the node info
// broadcast transactions
pm.txsCh = make(chan core.NewTxsEvent, txChanSize)
pm.txsSub = pm.txpool.SubscribeNewTxsEvent(pm.txsCh)
go pm.txBroadcastLoop()
// broadcast node metas
pm.metasCh = make(chan newMetasEvent, metaChanSize)
pm.metasSub = pm.nodeTable.SubscribeNewMetasEvent(pm.metasCh)
go pm.metaBroadcastLoop()
// broadcast mined blocks
pm.minedBlockSub = pm.eventMux.Subscribe(core.NewMinedBlockEvent{})
go pm.minedBroadcastLoop()
// run the peer set loop
pm.crsCh = make(chan core.NewCRSEvent)
pm.crsSub = pm.gov.SubscribeNewCRSEvent(pm.crsCh)
go pm.peerSetLoop()
// start sync handlers
go pm.syncer()
go pm.txsyncLoop()
go pm.metasyncLoop()
}
func (pm *ProtocolManager) Stop() {
log.Info("Stopping Ethereum protocol")
pm.txsSub.Unsubscribe() // quits txBroadcastLoop
pm.minedBlockSub.Unsubscribe() // quits blockBroadcastLoop
// Quit the sync loop.
// After this send has completed, no new peers will be accepted.
pm.noMorePeers <- struct{}{}
// Quit fetcher, txsyncLoop.
close(pm.quitSync)
// Disconnect existing sessions.
// This also closes the gate for any new registrations on the peer set.
// sessions which are already established but not added to pm.peers yet
// will exit when they try to register.
pm.peers.Close()
// Wait for all peer handler goroutines and the loops to come down.
pm.wg.Wait()
log.Info("Ethereum protocol stopped")
}
func (pm *ProtocolManager) newPeer(pv int, p *p2p.Peer, rw p2p.MsgReadWriter) *peer {
return newPeer(pv, 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 {
// Ignore maxPeers if this is a trusted peer
if pm.peers.Len() >= pm.maxPeers && !p.Peer.Info().Network.Trusted {
return p2p.DiscTooManyPeers
}
p.Log().Debug("Ethereum peer connected", "name", p.Name())
// Execute the Ethereum handshake
var (
genesis = pm.blockchain.Genesis()
head = pm.blockchain.CurrentHeader()
hash = head.Hash()
number = head.Number.Uint64()
td = pm.blockchain.GetTd(hash, number)
)
if err := p.Handshake(pm.networkID, td, hash, genesis.Hash()); err != nil {
p.Log().Debug("Ethereum handshake failed", "err", err)
return err
}
if rw, ok := p.rw.(*meteredMsgReadWriter); ok {
rw.Init(p.version)
}
// Register the peer locally
if err := pm.peers.Register(p); err != nil {
p.Log().Error("Ethereum peer registration failed", "err", 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); err != nil {
return err
}
// Propagate existing transactions. new transactions appearing
// after this will be sent via broadcasts.
pm.syncTransactions(p)
pm.syncNodeMetas(p)
// If we're DAO hard-fork aware, validate any remote peer with regard to the hard-fork
if daoBlock := pm.chainconfig.DAOForkBlock; daoBlock != nil {
// Request the peer's DAO fork header for extra-data validation
if err := p.RequestHeadersByNumber(daoBlock.Uint64(), 1, 0, false); err != nil {
return err
}
// Start a timer to disconnect if the peer doesn't reply in time
p.forkDrop = time.AfterFunc(daoChallengeTimeout, func() {
p.Log().Debug("Timed out DAO fork-check, dropping")
pm.removePeer(p.id)
})
// Make sure it's cleaned up if the peer dies off
defer func() {
if p.forkDrop != nil {
p.forkDrop.Stop()
p.forkDrop = nil
}
}()
}
// main loop. handle incoming messages.
for {
if err := pm.handleMsg(p); err != nil {
p.Log().Debug("Ethereum message handling failed", "err", err)
return err
}
}
}
// 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")
// Block header query, collect the requested headers and reply
case 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)
}
hashMode := query.Origin.Hash != (common.Hash{})
first := true
maxNonCanonical := uint64(100)
// 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 hashMode {
if first {
first = false
origin = pm.blockchain.GetHeaderByHash(query.Origin.Hash)
if origin != nil {
query.Origin.Number = origin.Number.Uint64()
}
} else {
origin = pm.blockchain.GetHeader(query.Origin.Hash, query.Origin.Number)
}
} else {
origin = pm.blockchain.GetHeaderByNumber(query.Origin.Number)
}
if origin == nil {
break
}
headers = append(headers, origin)
bytes += estHeaderRlpSize
// Advance to the next header of the query
switch {
case hashMode && query.Reverse:
// Hash based traversal towards the genesis block
ancestor := query.Skip + 1
if ancestor == 0 {
unknown = true
} else {
query.Origin.Hash, query.Origin.Number = pm.blockchain.GetAncestor(query.Origin.Hash, query.Origin.Number, ancestor, &maxNonCanonical)
unknown = (query.Origin.Hash == common.Hash{})
}
case hashMode && !query.Reverse:
// Hash based traversal towards the leaf block
var (
current = origin.Number.Uint64()
next = current + query.Skip + 1
)
if next <= current {
infos, _ := json.MarshalIndent(p.Peer.Info(), "", " ")
p.Log().Warn("GetBlockHeaders skip overflow attack", "current", current, "skip", query.Skip, "next", next, "attacker", infos)
unknown = true
} else {
if header := pm.blockchain.GetHeaderByNumber(next); header != nil {
nextHash := header.Hash()
expOldHash, _ := pm.blockchain.GetAncestor(nextHash, next, query.Skip+1, &maxNonCanonical)
if expOldHash == query.Origin.Hash {
query.Origin.Hash, query.Origin.Number = nextHash, next
} 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 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)
}
// If no headers were received, but we're expending a DAO fork check, maybe it's that
if len(headers) == 0 && p.forkDrop != nil {
// Possibly an empty reply to the fork header checks, sanity check TDs
verifyDAO := true
// If we already have a DAO header, we can check the peer's TD against it. If
// the peer's ahead of this, it too must have a reply to the DAO check
if daoHeader := pm.blockchain.GetHeaderByNumber(pm.chainconfig.DAOForkBlock.Uint64()); daoHeader != nil {
if _, td := p.Head(); td.Cmp(pm.blockchain.GetTd(daoHeader.Hash(), daoHeader.Number.Uint64())) >= 0 {
verifyDAO = false
}
}
// If we're seemingly on the same chain, disable the drop timer
if verifyDAO {
p.Log().Debug("Seems to be on the same side of the DAO fork")
p.forkDrop.Stop()
p.forkDrop = nil
return nil
}
}
// Filter out any explicitly requested headers, deliver the rest to the downloader
filter := len(headers) == 1
if filter {
// If it's a potential DAO fork check, validate against the rules
if p.forkDrop != nil && pm.chainconfig.DAOForkBlock.Cmp(headers[0].Number) == 0 {
// Disable the fork drop timer
p.forkDrop.Stop()
p.forkDrop = nil
// Validate the header and either drop the peer or continue
if err := misc.VerifyDAOHeaderExtraData(pm.chainconfig, headers[0]); err != nil {
p.Log().Debug("Verified to be on the other side of the DAO fork, dropping")
return err
}
p.Log().Debug("Verified to be on the same side of the DAO fork")
return nil
}
// Irrelevant of the fork checks, send the header to the fetcher just in case
headers = pm.fetcher.FilterHeaders(p.id, headers, time.Now())
}
if len(headers) > 0 || !filter {
err := pm.downloader.DeliverHeaders(p.id, headers)
if err != nil {
log.Debug("Failed to deliver headers", "err", err)
}
}
case 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.blockchain.GetBodyRLP(hash); len(data) != 0 {
bodies = append(bodies, data)
bytes += len(data)
}
}
return p.SendBlockBodiesRLP(bodies)
case 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
transactions := make([][]*types.Transaction, len(request))
uncles := make([][]*types.Header, len(request))
for i, body := range request {
transactions[i] = body.Transactions
uncles[i] = body.Uncles
}
// Filter out any explicitly requested bodies, deliver the rest to the downloader
filter := len(transactions) > 0 || len(uncles) > 0
if filter {
transactions, uncles = pm.fetcher.FilterBodies(p.id, transactions, uncles, time.Now())
}
if len(transactions) > 0 || len(uncles) > 0 || !filter {
err := pm.downloader.DeliverBodies(p.id, transactions, uncles)
if err != nil {
log.Debug("Failed to deliver bodies", "err", err)
}
}
case 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.blockchain.TrieNode(hash); err == nil {
data = append(data, entry)
bytes += len(entry)
}
}
return p.SendNodeData(data)
case msg.Code == NodeDataMsg:
// A batch of node state data arrived to one of our previous requests
var data [][]byte
if err := msg.Decode(&data); err != nil {
return errResp(ErrDecode, "msg %v: %v", msg, err)
}
// Deliver all to the downloader
if err := pm.downloader.DeliverNodeData(p.id, data); err != nil {
log.Debug("Failed to deliver node state data", "err", err)
}
case 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 []rlp.RawValue
)
for bytes < softResponseLimit && len(receipts) < downloader.MaxReceiptFetch {
// 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's receipts, skipping if unknown to us
results := pm.blockchain.GetReceiptsByHash(hash)
if results == nil {
if header := pm.blockchain.GetHeaderByHash(hash); header == nil || header.ReceiptHash != types.EmptyRootHash {
continue
}
}
// If known, encode and queue for response packet
if encoded, err := rlp.EncodeToBytes(results); err != nil {
log.Error("Failed to encode receipt", "err", err)
} else {
receipts = append(receipts, encoded)
bytes += len(encoded)
}
}
return p.SendReceiptsRLP(receipts)
case msg.Code == ReceiptsMsg:
// A batch of receipts arrived to one of our previous requests
var receipts [][]*types.Receipt
if err := msg.Decode(&receipts); err != nil {
return errResp(ErrDecode, "msg %v: %v", msg, err)
}
// Deliver all to the downloader
if err := pm.downloader.DeliverReceipts(p.id, receipts); err != nil {
log.Debug("Failed to deliver receipts", "err", err)
}
case msg.Code == NewBlockHashesMsg:
var announces newBlockHashesData
if err := msg.Decode(&announces); err != nil {
return errResp(ErrDecode, "%v: %v", msg, err)
}
// Mark the hashes as present at the remote node
for _, block := range announces {
p.MarkBlock(block.Hash)
}
// Schedule all the unknown hashes for retrieval
unknown := make(newBlockHashesData, 0, len(announces))
for _, block := range announces {
if !pm.blockchain.HasBlock(block.Hash, block.Number) {
unknown = append(unknown, block)
}
}
for _, block := range unknown {
pm.fetcher.Notify(p.id, block.Hash, block.Number, time.Now(), 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)
}
request.Block.ReceivedAt = msg.ReceivedAt
request.Block.ReceivedFrom = p
// Mark the peer as owning the block and schedule it for import
p.MarkBlock(request.Block.Hash())
pm.fetcher.Enqueue(p.id, request.Block)
// Assuming the block is importable by the peer, but possibly not yet done so,
// calculate the head hash and TD that the peer truly must have.
var (
trueHead = request.Block.ParentHash()
trueTD = new(big.Int).Sub(request.TD, request.Block.Difficulty())
)
// Update the peers total difficulty if better than the previous
if _, td := p.Head(); trueTD.Cmp(td) > 0 {
p.SetHead(trueHead, trueTD)
// Schedule a sync if above ours. Note, this will not fire a sync for a gap of
// a singe block (as the true TD is below the propagated block), however this
// scenario should easily be covered by the fetcher.
currentBlock := pm.blockchain.CurrentBlock()
if trueTD.Cmp(pm.blockchain.GetTd(currentBlock.Hash(), currentBlock.NumberU64())) > 0 {
go pm.synchronise(p)
}
}
case msg.Code == TxMsg:
// Transactions arrived, make sure we have a valid and fresh chain to handle them
if atomic.LoadUint32(&pm.acceptTxs) == 0 {
break
}
// Transactions can be processed, 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())
}
pm.txpool.AddRemotes(txs)
case msg.Code == MetaMsg:
var metas []*NodeMeta
if err := msg.Decode(&metas); err != nil {
return errResp(ErrDecode, "msg %v: %v", msg, err)
}
for i, meta := range metas {
if meta == nil {
return errResp(ErrDecode, "node meta %d is nil", i)
}
p.MarkNodeMeta(meta.Hash())
}
pm.nodeTable.Add(metas)
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.blockchain.GetBlock(block.ParentHash(), block.NumberU64()-1); parent != nil {
td = new(big.Int).Add(block.Difficulty(), pm.blockchain.GetTd(block.ParentHash(), block.NumberU64()-1))
} else {
log.Error("Propagating dangling block", "number", block.Number(), "hash", hash)
return
}
// Send the block to a subset of our peers
transfer := peers[:int(math.Sqrt(float64(len(peers))))]
for _, peer := range transfer {
peer.AsyncSendNewBlock(block, td)
}
log.Trace("Propagated block", "hash", hash, "recipients", len(transfer), "duration", common.PrettyDuration(time.Since(block.ReceivedAt)))
return
}
// Otherwise if the block is indeed in out own chain, announce it
if pm.blockchain.HasBlock(hash, block.NumberU64()) {
for _, peer := range peers {
peer.AsyncSendNewBlockHash(block)
}
log.Trace("Announced block", "hash", hash, "recipients", len(peers), "duration", common.PrettyDuration(time.Since(block.ReceivedAt)))
}
}
// BroadcastTxs will propagate a batch of transactions to all peers which are not known to
// already have the given transaction.
func (pm *ProtocolManager) BroadcastTxs(txs types.Transactions) {
var txset = make(map[*peer]types.Transactions)
// Broadcast transactions to a batch of peers not knowing about it
for _, tx := range txs {
peers := pm.peers.PeersWithoutTx(tx.Hash())
for _, peer := range peers {
txset[peer] = append(txset[peer], tx)
}
log.Trace("Broadcast transaction", "hash", tx.Hash(), "recipients", len(peers))
}
// FIXME include this again: peers = peers[:int(math.Sqrt(float64(len(peers))))]
for peer, txs := range txset {
peer.AsyncSendTransactions(txs)
}
}
// BroadcastMetas will propagate node metas to its peers.
func (pm *ProtocolManager) BroadcastMetas(metas []*NodeMeta) {
var metaset = make(map[*peer][]*NodeMeta)
for _, meta := range metas {
peers := pm.peers.PeersWithoutNodeMeta(meta.Hash())
for _, peer := range peers {
metaset[peer] = append(metaset[peer], meta)
}
log.Trace("Broadcast meta", "ID", meta.ID, "recipients", len(peers))
}
for peer, metas := range metaset {
peer.AsyncSendNodeMetas(metas)
}
}
// Mined broadcast loop
func (pm *ProtocolManager) minedBroadcastLoop() {
// automatically stops if unsubscribe
for obj := range pm.minedBlockSub.Chan() {
if ev, ok := obj.Data.(core.NewMinedBlockEvent); ok {
pm.BroadcastBlock(ev.Block, true) // First propagate block to peers
pm.BroadcastBlock(ev.Block, false) // Only then announce to the rest
}
}
}
func (pm *ProtocolManager) txBroadcastLoop() {
for {
select {
case event := <-pm.txsCh:
pm.BroadcastTxs(event.Txs)
// Err() channel will be closed when unsubscribing.
case <-pm.txsSub.Err():
return
}
}
}
func (pm *ProtocolManager) metaBroadcastLoop() {
for {
select {
case event := <-pm.metasCh:
pm.BroadcastMetas(event.Metas)
// Err() channel will be closed when unsubscribing.
case <-pm.metasSub.Err():
return
}
}
}
// a loop keep building and maintaining peers in notary set.
// TODO: finish this
func (pm *ProtocolManager) peerSetLoop() {
for {
select {
case event := <-pm.crsCh:
pm.peers.BuildNotaryConn(event.Round)
pm.peers.BuildDKGConn(event.Round)
pm.peers.ForgetNotaryConn(event.Round - 1)
pm.peers.ForgetDKGConn(event.Round - 1)
case <-pm.quitSync:
return
}
}
}
// NodeInfo represents a short summary of the Ethereum sub-protocol metadata
// known about the host peer.
type NodeInfo struct {
Network uint64 `json:"network"` // Ethereum network ID (1=Frontier, 2=Morden, Ropsten=3, Rinkeby=4)
Difficulty *big.Int `json:"difficulty"` // Total difficulty of the host's blockchain
Genesis common.Hash `json:"genesis"` // SHA3 hash of the host's genesis block
Config *params.ChainConfig `json:"config"` // Chain configuration for the fork rules
Head common.Hash `json:"head"` // SHA3 hash of the host's best owned block
}
// NodeInfo retrieves some protocol metadata about the running host node.
func (pm *ProtocolManager) NodeInfo() *NodeInfo {
currentBlock := pm.blockchain.CurrentBlock()
return &NodeInfo{
Network: pm.networkID,
Difficulty: pm.blockchain.GetTd(currentBlock.Hash(), currentBlock.NumberU64()),
Genesis: pm.blockchain.Genesis().Hash(),
Config: pm.blockchain.Config(),
Head: currentBlock.Hash(),
}
}