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762 lines
21 KiB
762 lines
21 KiB
package pex
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import (
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"fmt"
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"reflect"
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"sync"
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"time"
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"github.com/pkg/errors"
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amino "github.com/tendermint/go-amino"
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cmn "github.com/tendermint/tendermint/libs/common"
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"github.com/tendermint/tendermint/p2p"
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"github.com/tendermint/tendermint/p2p/conn"
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)
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type Peer = p2p.Peer
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const (
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// PexChannel is a channel for PEX messages
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PexChannel = byte(0x00)
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// over-estimate of max NetAddress size
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// hexID (40) + IP (16) + Port (2) + Name (100) ...
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// NOTE: dont use massive DNS name ..
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maxAddressSize = 256
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// NOTE: amplificaiton factor!
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// small request results in up to maxMsgSize response
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maxMsgSize = maxAddressSize * maxGetSelection
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// ensure we have enough peers
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defaultEnsurePeersPeriod = 30 * time.Second
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// Seed/Crawler constants
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// minTimeBetweenCrawls is a minimum time between attempts to crawl a peer.
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minTimeBetweenCrawls = 2 * time.Minute
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// check some peers every this
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crawlPeerPeriod = 30 * time.Second
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maxAttemptsToDial = 16 // ~ 35h in total (last attempt - 18h)
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// if node connects to seed, it does not have any trusted peers.
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// Especially in the beginning, node should have more trusted peers than
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// untrusted.
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biasToSelectNewPeers = 30 // 70 to select good peers
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)
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type errMaxAttemptsToDial struct {
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}
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func (e errMaxAttemptsToDial) Error() string {
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return fmt.Sprintf("reached max attempts %d to dial", maxAttemptsToDial)
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}
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type errTooEarlyToDial struct {
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backoffDuration time.Duration
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lastDialed time.Time
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}
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func (e errTooEarlyToDial) Error() string {
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return fmt.Sprintf(
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"too early to dial (backoff duration: %d, last dialed: %v, time since: %v)",
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e.backoffDuration, e.lastDialed, time.Since(e.lastDialed))
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}
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// PEXReactor handles PEX (peer exchange) and ensures that an
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// adequate number of peers are connected to the switch.
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//
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// It uses `AddrBook` (address book) to store `NetAddress`es of the peers.
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//
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// ## Preventing abuse
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//
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// Only accept pexAddrsMsg from peers we sent a corresponding pexRequestMsg too.
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// Only accept one pexRequestMsg every ~defaultEnsurePeersPeriod.
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type PEXReactor struct {
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p2p.BaseReactor
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book AddrBook
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config *PEXReactorConfig
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ensurePeersPeriod time.Duration // TODO: should go in the config
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// maps to prevent abuse
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requestsSent *cmn.CMap // ID->struct{}: unanswered send requests
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lastReceivedRequests *cmn.CMap // ID->time.Time: last time peer requested from us
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seedAddrs []*p2p.NetAddress
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attemptsToDial sync.Map // address (string) -> {number of attempts (int), last time dialed (time.Time)}
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// seed/crawled mode fields
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crawlPeerInfos map[p2p.ID]crawlPeerInfo
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}
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func (r *PEXReactor) minReceiveRequestInterval() time.Duration {
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// NOTE: must be less than ensurePeersPeriod, otherwise we'll request
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// peers too quickly from others and they'll think we're bad!
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return r.ensurePeersPeriod / 3
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}
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// PEXReactorConfig holds reactor specific configuration data.
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type PEXReactorConfig struct {
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// Seed/Crawler mode
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SeedMode bool
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// We want seeds to only advertise good peers. Therefore they should wait at
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// least as long as we expect it to take for a peer to become good before
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// disconnecting.
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SeedDisconnectWaitPeriod time.Duration
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// Seeds is a list of addresses reactor may use
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// if it can't connect to peers in the addrbook.
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Seeds []string
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}
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type _attemptsToDial struct {
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number int
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lastDialed time.Time
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}
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// NewPEXReactor creates new PEX reactor.
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func NewPEXReactor(b AddrBook, config *PEXReactorConfig) *PEXReactor {
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r := &PEXReactor{
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book: b,
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config: config,
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ensurePeersPeriod: defaultEnsurePeersPeriod,
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requestsSent: cmn.NewCMap(),
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lastReceivedRequests: cmn.NewCMap(),
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crawlPeerInfos: make(map[p2p.ID]crawlPeerInfo),
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}
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r.BaseReactor = *p2p.NewBaseReactor("PEXReactor", r)
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return r
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}
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// OnStart implements BaseService
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func (r *PEXReactor) OnStart() error {
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err := r.book.Start()
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if err != nil && err != cmn.ErrAlreadyStarted {
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return err
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}
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numOnline, seedAddrs, err := r.checkSeeds()
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if err != nil {
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return err
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} else if numOnline == 0 && r.book.Empty() {
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return errors.New("Address book is empty and couldn't resolve any seed nodes")
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}
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r.seedAddrs = seedAddrs
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// Check if this node should run
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// in seed/crawler mode
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if r.config.SeedMode {
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go r.crawlPeersRoutine()
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} else {
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go r.ensurePeersRoutine()
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}
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return nil
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}
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// OnStop implements BaseService
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func (r *PEXReactor) OnStop() {
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r.book.Stop()
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}
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// GetChannels implements Reactor
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func (r *PEXReactor) GetChannels() []*conn.ChannelDescriptor {
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return []*conn.ChannelDescriptor{
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{
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ID: PexChannel,
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Priority: 1,
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SendQueueCapacity: 10,
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},
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}
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}
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// AddPeer implements Reactor by adding peer to the address book (if inbound)
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// or by requesting more addresses (if outbound).
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func (r *PEXReactor) AddPeer(p Peer) {
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if p.IsOutbound() {
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// For outbound peers, the address is already in the books -
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// either via DialPeersAsync or r.Receive.
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// Ask it for more peers if we need.
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if r.book.NeedMoreAddrs() {
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r.RequestAddrs(p)
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}
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} else {
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// inbound peer is its own source
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addr, err := p.NodeInfo().NetAddress()
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if err != nil {
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r.Logger.Error("Failed to get peer NetAddress", "err", err, "peer", p)
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return
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}
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// Make it explicit that addr and src are the same for an inbound peer.
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src := addr
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// add to book. dont RequestAddrs right away because
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// we don't trust inbound as much - let ensurePeersRoutine handle it.
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err = r.book.AddAddress(addr, src)
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r.logErrAddrBook(err)
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}
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}
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// RemovePeer implements Reactor by resetting peer's requests info.
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func (r *PEXReactor) RemovePeer(p Peer, reason interface{}) {
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id := string(p.ID())
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r.requestsSent.Delete(id)
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r.lastReceivedRequests.Delete(id)
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}
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func (r *PEXReactor) logErrAddrBook(err error) {
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if err != nil {
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switch err.(type) {
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case ErrAddrBookNilAddr:
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r.Logger.Error("Failed to add new address", "err", err)
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default:
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// non-routable, self, full book, private, etc.
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r.Logger.Debug("Failed to add new address", "err", err)
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}
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}
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}
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// Receive implements Reactor by handling incoming PEX messages.
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func (r *PEXReactor) Receive(chID byte, src Peer, msgBytes []byte) {
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msg, err := decodeMsg(msgBytes)
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if err != nil {
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r.Logger.Error("Error decoding message", "src", src, "chId", chID, "msg", msg, "err", err, "bytes", msgBytes)
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r.Switch.StopPeerForError(src, err)
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return
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}
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r.Logger.Debug("Received message", "src", src, "chId", chID, "msg", msg)
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switch msg := msg.(type) {
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case *pexRequestMessage:
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// NOTE: this is a prime candidate for amplification attacks,
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// so it's important we
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// 1) restrict how frequently peers can request
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// 2) limit the output size
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// If we're a seed and this is an inbound peer,
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// respond once and disconnect.
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if r.config.SeedMode && !src.IsOutbound() {
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id := string(src.ID())
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v := r.lastReceivedRequests.Get(id)
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if v != nil {
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// FlushStop/StopPeer are already
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// running in a go-routine.
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return
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}
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r.lastReceivedRequests.Set(id, time.Now())
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// Send addrs and disconnect
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r.SendAddrs(src, r.book.GetSelectionWithBias(biasToSelectNewPeers))
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go func() {
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// In a go-routine so it doesn't block .Receive.
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src.FlushStop()
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r.Switch.StopPeerGracefully(src)
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}()
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} else {
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// Check we're not receiving requests too frequently.
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if err := r.receiveRequest(src); err != nil {
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r.Switch.StopPeerForError(src, err)
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return
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}
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r.SendAddrs(src, r.book.GetSelection())
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}
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case *pexAddrsMessage:
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// If we asked for addresses, add them to the book
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if err := r.ReceiveAddrs(msg.Addrs, src); err != nil {
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r.Switch.StopPeerForError(src, err)
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return
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}
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default:
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r.Logger.Error(fmt.Sprintf("Unknown message type %v", reflect.TypeOf(msg)))
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}
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}
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// enforces a minimum amount of time between requests
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func (r *PEXReactor) receiveRequest(src Peer) error {
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id := string(src.ID())
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v := r.lastReceivedRequests.Get(id)
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if v == nil {
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// initialize with empty time
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lastReceived := time.Time{}
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r.lastReceivedRequests.Set(id, lastReceived)
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return nil
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}
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lastReceived := v.(time.Time)
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if lastReceived.Equal(time.Time{}) {
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// first time gets a free pass. then we start tracking the time
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lastReceived = time.Now()
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r.lastReceivedRequests.Set(id, lastReceived)
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return nil
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}
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now := time.Now()
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minInterval := r.minReceiveRequestInterval()
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if now.Sub(lastReceived) < minInterval {
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return fmt.Errorf("peer (%v) sent next PEX request too soon. lastReceived: %v, now: %v, minInterval: %v. Disconnecting",
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src.ID(),
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lastReceived,
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now,
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minInterval,
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)
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}
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r.lastReceivedRequests.Set(id, now)
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return nil
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}
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// RequestAddrs asks peer for more addresses if we do not already have a
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// request out for this peer.
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func (r *PEXReactor) RequestAddrs(p Peer) {
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id := string(p.ID())
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if r.requestsSent.Has(id) {
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return
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}
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r.Logger.Debug("Request addrs", "from", p)
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r.requestsSent.Set(id, struct{}{})
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p.Send(PexChannel, cdc.MustMarshalBinaryBare(&pexRequestMessage{}))
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}
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// ReceiveAddrs adds the given addrs to the addrbook if theres an open
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// request for this peer and deletes the open request.
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// If there's no open request for the src peer, it returns an error.
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func (r *PEXReactor) ReceiveAddrs(addrs []*p2p.NetAddress, src Peer) error {
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id := string(src.ID())
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if !r.requestsSent.Has(id) {
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return errors.New("unsolicited pexAddrsMessage")
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}
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r.requestsSent.Delete(id)
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srcAddr, err := src.NodeInfo().NetAddress()
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if err != nil {
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return err
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}
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for _, netAddr := range addrs {
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// Validate netAddr. Disconnect from a peer if it sends us invalid data.
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if netAddr == nil {
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return errors.New("nil address in pexAddrsMessage")
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}
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// TODO: extract validating logic from NewNetAddressString
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// and put it in netAddr#Valid (#2722)
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na, err := p2p.NewNetAddressString(netAddr.String())
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if err != nil {
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return fmt.Errorf("%s address in pexAddrsMessage is invalid: %v",
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netAddr.String(),
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err,
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)
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}
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// NOTE: we check netAddr validity and routability in book#AddAddress.
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err = r.book.AddAddress(na, srcAddr)
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if err != nil {
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r.logErrAddrBook(err)
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// XXX: should we be strict about incoming data and disconnect from a
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// peer here too?
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continue
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}
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// If this address came from a seed node, try to connect to it without
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// waiting.
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for _, seedAddr := range r.seedAddrs {
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if seedAddr.Equals(srcAddr) {
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r.ensurePeers()
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}
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}
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}
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return nil
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}
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// SendAddrs sends addrs to the peer.
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func (r *PEXReactor) SendAddrs(p Peer, netAddrs []*p2p.NetAddress) {
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p.Send(PexChannel, cdc.MustMarshalBinaryBare(&pexAddrsMessage{Addrs: netAddrs}))
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}
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// SetEnsurePeersPeriod sets period to ensure peers connected.
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func (r *PEXReactor) SetEnsurePeersPeriod(d time.Duration) {
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r.ensurePeersPeriod = d
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}
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// Ensures that sufficient peers are connected. (continuous)
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func (r *PEXReactor) ensurePeersRoutine() {
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var (
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seed = cmn.NewRand()
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jitter = seed.Int63n(r.ensurePeersPeriod.Nanoseconds())
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)
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// Randomize first round of communication to avoid thundering herd.
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// If no peers are present directly start connecting so we guarantee swift
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// setup with the help of configured seeds.
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if r.nodeHasSomePeersOrDialingAny() {
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time.Sleep(time.Duration(jitter))
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}
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// fire once immediately.
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// ensures we dial the seeds right away if the book is empty
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r.ensurePeers()
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// fire periodically
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ticker := time.NewTicker(r.ensurePeersPeriod)
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for {
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select {
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case <-ticker.C:
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r.ensurePeers()
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case <-r.Quit():
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ticker.Stop()
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return
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}
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}
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}
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// ensurePeers ensures that sufficient peers are connected. (once)
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//
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// heuristic that we haven't perfected yet, or, perhaps is manually edited by
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// the node operator. It should not be used to compute what addresses are
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// already connected or not.
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func (r *PEXReactor) ensurePeers() {
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var (
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out, in, dial = r.Switch.NumPeers()
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numToDial = r.Switch.MaxNumOutboundPeers() - (out + dial)
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)
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r.Logger.Info(
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"Ensure peers",
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"numOutPeers", out,
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"numInPeers", in,
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"numDialing", dial,
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"numToDial", numToDial,
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)
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if numToDial <= 0 {
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return
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}
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// bias to prefer more vetted peers when we have fewer connections.
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// not perfect, but somewhate ensures that we prioritize connecting to more-vetted
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// NOTE: range here is [10, 90]. Too high ?
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newBias := cmn.MinInt(out, 8)*10 + 10
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toDial := make(map[p2p.ID]*p2p.NetAddress)
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// Try maxAttempts times to pick numToDial addresses to dial
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maxAttempts := numToDial * 3
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for i := 0; i < maxAttempts && len(toDial) < numToDial; i++ {
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try := r.book.PickAddress(newBias)
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if try == nil {
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continue
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}
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if _, selected := toDial[try.ID]; selected {
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continue
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}
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if r.Switch.IsDialingOrExistingAddress(try) {
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continue
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}
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// TODO: consider moving some checks from toDial into here
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// so we don't even consider dialing peers that we want to wait
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// before dialling again, or have dialed too many times already
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r.Logger.Info("Will dial address", "addr", try)
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toDial[try.ID] = try
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}
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// Dial picked addresses
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for _, addr := range toDial {
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go func(addr *p2p.NetAddress) {
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err := r.dialPeer(addr)
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if err != nil {
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switch err.(type) {
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case errMaxAttemptsToDial, errTooEarlyToDial:
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r.Logger.Debug(err.Error(), "addr", addr)
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default:
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r.Logger.Error(err.Error(), "addr", addr)
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}
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}
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}(addr)
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}
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if r.book.NeedMoreAddrs() {
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// 1) Pick a random peer and ask for more.
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peers := r.Switch.Peers().List()
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peersCount := len(peers)
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if peersCount > 0 {
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peer := peers[cmn.RandInt()%peersCount] // nolint: gas
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r.Logger.Info("We need more addresses. Sending pexRequest to random peer", "peer", peer)
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r.RequestAddrs(peer)
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}
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// 2) Dial seeds if we are not dialing anyone.
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// This is done in addition to asking a peer for addresses to work-around
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// peers not participating in PEX.
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if len(toDial) == 0 {
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r.Logger.Info("No addresses to dial. Falling back to seeds")
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r.dialSeeds()
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}
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}
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}
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func (r *PEXReactor) dialAttemptsInfo(addr *p2p.NetAddress) (attempts int, lastDialed time.Time) {
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_attempts, ok := r.attemptsToDial.Load(addr.DialString())
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if !ok {
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return
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}
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atd := _attempts.(_attemptsToDial)
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return atd.number, atd.lastDialed
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}
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func (r *PEXReactor) dialPeer(addr *p2p.NetAddress) error {
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attempts, lastDialed := r.dialAttemptsInfo(addr)
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if attempts > maxAttemptsToDial {
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// TODO(melekes): have a blacklist in the addrbook with peers whom we've
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// failed to connect to. Then we can clean up attemptsToDial, which acts as
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// a blacklist currently.
|
|
// https://github.com/tendermint/tendermint/issues/3572
|
|
r.book.MarkBad(addr)
|
|
return errMaxAttemptsToDial{}
|
|
}
|
|
|
|
// exponential backoff if it's not our first attempt to dial given address
|
|
if attempts > 0 {
|
|
jitterSeconds := time.Duration(cmn.RandFloat64() * float64(time.Second)) // 1s == (1e9 ns)
|
|
backoffDuration := jitterSeconds + ((1 << uint(attempts)) * time.Second)
|
|
sinceLastDialed := time.Since(lastDialed)
|
|
if sinceLastDialed < backoffDuration {
|
|
return errTooEarlyToDial{backoffDuration, lastDialed}
|
|
}
|
|
}
|
|
|
|
err := r.Switch.DialPeerWithAddress(addr)
|
|
if err != nil {
|
|
if _, ok := err.(p2p.ErrCurrentlyDialingOrExistingAddress); ok {
|
|
return err
|
|
}
|
|
|
|
markAddrInBookBasedOnErr(addr, r.book, err)
|
|
switch err.(type) {
|
|
case p2p.ErrSwitchAuthenticationFailure:
|
|
// NOTE: addr is removed from addrbook in markAddrInBookBasedOnErr
|
|
r.attemptsToDial.Delete(addr.DialString())
|
|
default:
|
|
r.attemptsToDial.Store(addr.DialString(), _attemptsToDial{attempts + 1, time.Now()})
|
|
}
|
|
return errors.Wrapf(err, "dialing failed (attempts: %d)", attempts+1)
|
|
}
|
|
|
|
// cleanup any history
|
|
r.attemptsToDial.Delete(addr.DialString())
|
|
return nil
|
|
}
|
|
|
|
// checkSeeds checks that addresses are well formed.
|
|
// Returns number of seeds we can connect to, along with all seeds addrs.
|
|
// return err if user provided any badly formatted seed addresses.
|
|
// Doesn't error if the seed node can't be reached.
|
|
// numOnline returns -1 if no seed nodes were in the initial configuration.
|
|
func (r *PEXReactor) checkSeeds() (numOnline int, netAddrs []*p2p.NetAddress, err error) {
|
|
lSeeds := len(r.config.Seeds)
|
|
if lSeeds == 0 {
|
|
return -1, nil, nil
|
|
}
|
|
netAddrs, errs := p2p.NewNetAddressStrings(r.config.Seeds)
|
|
numOnline = lSeeds - len(errs)
|
|
for _, err := range errs {
|
|
switch e := err.(type) {
|
|
case p2p.ErrNetAddressLookup:
|
|
r.Logger.Error("Connecting to seed failed", "err", e)
|
|
default:
|
|
return 0, nil, errors.Wrap(e, "seed node configuration has error")
|
|
}
|
|
}
|
|
return numOnline, netAddrs, nil
|
|
}
|
|
|
|
// randomly dial seeds until we connect to one or exhaust them
|
|
func (r *PEXReactor) dialSeeds() {
|
|
perm := cmn.RandPerm(len(r.seedAddrs))
|
|
// perm := r.Switch.rng.Perm(lSeeds)
|
|
for _, i := range perm {
|
|
// dial a random seed
|
|
seedAddr := r.seedAddrs[i]
|
|
err := r.Switch.DialPeerWithAddress(seedAddr)
|
|
if err == nil {
|
|
return
|
|
}
|
|
r.Switch.Logger.Error("Error dialing seed", "err", err, "seed", seedAddr)
|
|
}
|
|
r.Switch.Logger.Error("Couldn't connect to any seeds")
|
|
}
|
|
|
|
// AttemptsToDial returns the number of attempts to dial specific address. It
|
|
// returns 0 if never attempted or successfully connected.
|
|
func (r *PEXReactor) AttemptsToDial(addr *p2p.NetAddress) int {
|
|
lAttempts, attempted := r.attemptsToDial.Load(addr.DialString())
|
|
if attempted {
|
|
return lAttempts.(_attemptsToDial).number
|
|
}
|
|
return 0
|
|
}
|
|
|
|
//----------------------------------------------------------
|
|
|
|
// Explores the network searching for more peers. (continuous)
|
|
// Seed/Crawler Mode causes this node to quickly disconnect
|
|
// from peers, except other seed nodes.
|
|
func (r *PEXReactor) crawlPeersRoutine() {
|
|
// If we have any seed nodes, consult them first
|
|
if len(r.seedAddrs) > 0 {
|
|
r.dialSeeds()
|
|
} else {
|
|
// Do an initial crawl
|
|
r.crawlPeers(r.book.GetSelection())
|
|
}
|
|
|
|
// Fire periodically
|
|
ticker := time.NewTicker(crawlPeerPeriod)
|
|
|
|
for {
|
|
select {
|
|
case <-ticker.C:
|
|
r.attemptDisconnects()
|
|
r.crawlPeers(r.book.GetSelection())
|
|
r.cleanupCrawlPeerInfos()
|
|
case <-r.Quit():
|
|
return
|
|
}
|
|
}
|
|
}
|
|
|
|
// nodeHasSomePeersOrDialingAny returns true if the node is connected to some
|
|
// peers or dialing them currently.
|
|
func (r *PEXReactor) nodeHasSomePeersOrDialingAny() bool {
|
|
out, in, dial := r.Switch.NumPeers()
|
|
return out+in+dial > 0
|
|
}
|
|
|
|
// crawlPeerInfo handles temporary data needed for the network crawling
|
|
// performed during seed/crawler mode.
|
|
type crawlPeerInfo struct {
|
|
Addr *p2p.NetAddress `json:"addr"`
|
|
// The last time we crawled the peer or attempted to do so.
|
|
LastCrawled time.Time `json:"last_crawled"`
|
|
}
|
|
|
|
// crawlPeers will crawl the network looking for new peer addresses.
|
|
func (r *PEXReactor) crawlPeers(addrs []*p2p.NetAddress) {
|
|
now := time.Now()
|
|
|
|
for _, addr := range addrs {
|
|
peerInfo, ok := r.crawlPeerInfos[addr.ID]
|
|
|
|
// Do not attempt to connect with peers we recently crawled.
|
|
if ok && now.Sub(peerInfo.LastCrawled) < minTimeBetweenCrawls {
|
|
continue
|
|
}
|
|
|
|
// Record crawling attempt.
|
|
r.crawlPeerInfos[addr.ID] = crawlPeerInfo{
|
|
Addr: addr,
|
|
LastCrawled: now,
|
|
}
|
|
|
|
err := r.dialPeer(addr)
|
|
if err != nil {
|
|
switch err.(type) {
|
|
case errMaxAttemptsToDial, errTooEarlyToDial:
|
|
r.Logger.Debug(err.Error(), "addr", addr)
|
|
default:
|
|
r.Logger.Error(err.Error(), "addr", addr)
|
|
}
|
|
continue
|
|
}
|
|
|
|
peer := r.Switch.Peers().Get(addr.ID)
|
|
if peer != nil {
|
|
r.RequestAddrs(peer)
|
|
}
|
|
}
|
|
}
|
|
|
|
func (r *PEXReactor) cleanupCrawlPeerInfos() {
|
|
for id, info := range r.crawlPeerInfos {
|
|
// If we did not crawl a peer for 24 hours, it means the peer was removed
|
|
// from the addrbook => remove
|
|
//
|
|
// 10000 addresses / maxGetSelection = 40 cycles to get all addresses in
|
|
// the ideal case,
|
|
// 40 * crawlPeerPeriod ~ 20 minutes
|
|
if time.Since(info.LastCrawled) > 24*time.Hour {
|
|
delete(r.crawlPeerInfos, id)
|
|
}
|
|
}
|
|
}
|
|
|
|
// attemptDisconnects checks if we've been with each peer long enough to disconnect
|
|
func (r *PEXReactor) attemptDisconnects() {
|
|
for _, peer := range r.Switch.Peers().List() {
|
|
if peer.Status().Duration < r.config.SeedDisconnectWaitPeriod {
|
|
continue
|
|
}
|
|
if peer.IsPersistent() {
|
|
continue
|
|
}
|
|
r.Switch.StopPeerGracefully(peer)
|
|
}
|
|
}
|
|
|
|
func markAddrInBookBasedOnErr(addr *p2p.NetAddress, book AddrBook, err error) {
|
|
// TODO: detect more "bad peer" scenarios
|
|
switch err.(type) {
|
|
case p2p.ErrSwitchAuthenticationFailure:
|
|
book.MarkBad(addr)
|
|
default:
|
|
book.MarkAttempt(addr)
|
|
}
|
|
}
|
|
|
|
//-----------------------------------------------------------------------------
|
|
// Messages
|
|
|
|
// PexMessage is a primary type for PEX messages. Underneath, it could contain
|
|
// either pexRequestMessage, or pexAddrsMessage messages.
|
|
type PexMessage interface{}
|
|
|
|
func RegisterPexMessage(cdc *amino.Codec) {
|
|
cdc.RegisterInterface((*PexMessage)(nil), nil)
|
|
cdc.RegisterConcrete(&pexRequestMessage{}, "tendermint/p2p/PexRequestMessage", nil)
|
|
cdc.RegisterConcrete(&pexAddrsMessage{}, "tendermint/p2p/PexAddrsMessage", nil)
|
|
}
|
|
|
|
func decodeMsg(bz []byte) (msg PexMessage, err error) {
|
|
if len(bz) > maxMsgSize {
|
|
return msg, fmt.Errorf("Msg exceeds max size (%d > %d)", len(bz), maxMsgSize)
|
|
}
|
|
err = cdc.UnmarshalBinaryBare(bz, &msg)
|
|
return
|
|
}
|
|
|
|
/*
|
|
A pexRequestMessage requests additional peer addresses.
|
|
*/
|
|
type pexRequestMessage struct {
|
|
}
|
|
|
|
func (m *pexRequestMessage) String() string {
|
|
return "[pexRequest]"
|
|
}
|
|
|
|
/*
|
|
A message with announced peer addresses.
|
|
*/
|
|
type pexAddrsMessage struct {
|
|
Addrs []*p2p.NetAddress
|
|
}
|
|
|
|
func (m *pexAddrsMessage) String() string {
|
|
return fmt.Sprintf("[pexAddrs %v]", m.Addrs)
|
|
}
|