plugeth/swarm/network/stream/stream.go
Felix Lange 30cd5c1854
all: new p2p node representation (#17643)
Package p2p/enode provides a generalized representation of p2p nodes
which can contain arbitrary information in key/value pairs. It is also
the new home for the node database. The "v4" identity scheme is also
moved here from p2p/enr to remove the dependency on Ethereum crypto from
that package.

Record signature handling is changed significantly. The identity scheme
registry is removed and acceptable schemes must be passed to any method
that needs identity. This means records must now be validated explicitly
after decoding.

The enode API is designed to make signature handling easy and safe: most
APIs around the codebase work with enode.Node, which is a wrapper around
a valid record. Going from enr.Record to enode.Node requires a valid
signature.

* p2p/discover: port to p2p/enode

This ports the discovery code to the new node representation in
p2p/enode. The wire protocol is unchanged, this can be considered a
refactoring change. The Kademlia table can now deal with nodes using an
arbitrary identity scheme. This requires a few incompatible API changes:

  - Table.Lookup is not available anymore. It used to take a public key
    as argument because v4 protocol requires one. Its replacement is
    LookupRandom.
  - Table.Resolve takes *enode.Node instead of NodeID. This is also for
    v4 protocol compatibility because nodes cannot be looked up by ID
    alone.
  - Types Node and NodeID are gone. Further commits in the series will be
    fixes all over the the codebase to deal with those removals.

* p2p: port to p2p/enode and discovery changes

This adapts package p2p to the changes in p2p/discover. All uses of
discover.Node and discover.NodeID are replaced by their equivalents from
p2p/enode.

New API is added to retrieve the enode.Node instance of a peer. The
behavior of Server.Self with discovery disabled is improved. It now
tries much harder to report a working IP address, falling back to
127.0.0.1 if no suitable address can be determined through other means.
These changes were needed for tests of other packages later in the
series.

* p2p/simulations, p2p/testing: port to p2p/enode

No surprises here, mostly replacements of discover.Node, discover.NodeID
with their new equivalents. The 'interesting' API changes are:

 - testing.ProtocolSession tracks complete nodes, not just their IDs.
 - adapters.NodeConfig has a new method to create a complete node.

These changes were needed to make swarm tests work.

Note that the NodeID change makes the code incompatible with old
simulation snapshots.

* whisper/whisperv5, whisper/whisperv6: port to p2p/enode

This port was easy because whisper uses []byte for node IDs and
URL strings in the API.

* eth: port to p2p/enode

Again, easy to port because eth uses strings for node IDs and doesn't
care about node information in any way.

* les: port to p2p/enode

Apart from replacing discover.NodeID with enode.ID, most changes are in
the server pool code. It now deals with complete nodes instead
of (Pubkey, IP, Port) triples. The database format is unchanged for now,
but we should probably change it to use the node database later.

* node: port to p2p/enode

This change simply replaces discover.Node and discover.NodeID with their
new equivalents.

* swarm/network: port to p2p/enode

Swarm has its own node address representation, BzzAddr, containing both
an overlay address (the hash of a secp256k1 public key) and an underlay
address (enode:// URL).

There are no changes to the BzzAddr format in this commit, but certain
operations such as creating a BzzAddr from a node ID are now impossible
because node IDs aren't public keys anymore.

Most swarm-related changes in the series remove uses of
NewAddrFromNodeID, replacing it with NewAddr which takes a complete node
as argument. ToOverlayAddr is removed because we can just use the node
ID directly.
2018-09-25 00:59:00 +02:00

734 lines
18 KiB
Go

// Copyright 2018 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 stream
import (
"context"
"fmt"
"math"
"sync"
"time"
"github.com/ethereum/go-ethereum/metrics"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/p2p/enode"
"github.com/ethereum/go-ethereum/p2p/protocols"
"github.com/ethereum/go-ethereum/rpc"
"github.com/ethereum/go-ethereum/swarm/log"
"github.com/ethereum/go-ethereum/swarm/network"
"github.com/ethereum/go-ethereum/swarm/network/stream/intervals"
"github.com/ethereum/go-ethereum/swarm/pot"
"github.com/ethereum/go-ethereum/swarm/state"
"github.com/ethereum/go-ethereum/swarm/storage"
)
const (
Low uint8 = iota
Mid
High
Top
PriorityQueue = 4 // number of priority queues - Low, Mid, High, Top
PriorityQueueCap = 4096 // queue capacity
HashSize = 32
)
// Registry registry for outgoing and incoming streamer constructors
type Registry struct {
addr enode.ID
api *API
skipCheck bool
clientMu sync.RWMutex
serverMu sync.RWMutex
peersMu sync.RWMutex
serverFuncs map[string]func(*Peer, string, bool) (Server, error)
clientFuncs map[string]func(*Peer, string, bool) (Client, error)
peers map[enode.ID]*Peer
delivery *Delivery
intervalsStore state.Store
doRetrieve bool
}
// RegistryOptions holds optional values for NewRegistry constructor.
type RegistryOptions struct {
SkipCheck bool
DoSync bool
DoRetrieve bool
SyncUpdateDelay time.Duration
}
// NewRegistry is Streamer constructor
func NewRegistry(localID enode.ID, delivery *Delivery, syncChunkStore storage.SyncChunkStore, intervalsStore state.Store, options *RegistryOptions) *Registry {
if options == nil {
options = &RegistryOptions{}
}
if options.SyncUpdateDelay <= 0 {
options.SyncUpdateDelay = 15 * time.Second
}
streamer := &Registry{
addr: localID,
skipCheck: options.SkipCheck,
serverFuncs: make(map[string]func(*Peer, string, bool) (Server, error)),
clientFuncs: make(map[string]func(*Peer, string, bool) (Client, error)),
peers: make(map[enode.ID]*Peer),
delivery: delivery,
intervalsStore: intervalsStore,
doRetrieve: options.DoRetrieve,
}
streamer.api = NewAPI(streamer)
delivery.getPeer = streamer.getPeer
streamer.RegisterServerFunc(swarmChunkServerStreamName, func(_ *Peer, _ string, _ bool) (Server, error) {
return NewSwarmChunkServer(delivery.chunkStore), nil
})
streamer.RegisterClientFunc(swarmChunkServerStreamName, func(p *Peer, t string, live bool) (Client, error) {
return NewSwarmSyncerClient(p, syncChunkStore, NewStream(swarmChunkServerStreamName, t, live))
})
RegisterSwarmSyncerServer(streamer, syncChunkStore)
RegisterSwarmSyncerClient(streamer, syncChunkStore)
if options.DoSync {
// latestIntC function ensures that
// - receiving from the in chan is not blocked by processing inside the for loop
// - the latest int value is delivered to the loop after the processing is done
// In context of NeighbourhoodDepthC:
// after the syncing is done updating inside the loop, we do not need to update on the intermediate
// depth changes, only to the latest one
latestIntC := func(in <-chan int) <-chan int {
out := make(chan int, 1)
go func() {
defer close(out)
for i := range in {
select {
case <-out:
default:
}
out <- i
}
}()
return out
}
go func() {
// wait for kademlia table to be healthy
time.Sleep(options.SyncUpdateDelay)
kad := streamer.delivery.kad
depthC := latestIntC(kad.NeighbourhoodDepthC())
addressBookSizeC := latestIntC(kad.AddrCountC())
// initial requests for syncing subscription to peers
streamer.updateSyncing()
for depth := range depthC {
log.Debug("Kademlia neighbourhood depth change", "depth", depth)
// Prevent too early sync subscriptions by waiting until there are no
// new peers connecting. Sync streams updating will be done after no
// peers are connected for at least SyncUpdateDelay period.
timer := time.NewTimer(options.SyncUpdateDelay)
// Hard limit to sync update delay, preventing long delays
// on a very dynamic network
maxTimer := time.NewTimer(3 * time.Minute)
loop:
for {
select {
case <-maxTimer.C:
// force syncing update when a hard timeout is reached
log.Trace("Sync subscriptions update on hard timeout")
// request for syncing subscription to new peers
streamer.updateSyncing()
break loop
case <-timer.C:
// start syncing as no new peers has been added to kademlia
// for some time
log.Trace("Sync subscriptions update")
// request for syncing subscription to new peers
streamer.updateSyncing()
break loop
case size := <-addressBookSizeC:
log.Trace("Kademlia address book size changed on depth change", "size", size)
// new peers has been added to kademlia,
// reset the timer to prevent early sync subscriptions
if !timer.Stop() {
<-timer.C
}
timer.Reset(options.SyncUpdateDelay)
}
}
timer.Stop()
maxTimer.Stop()
}
}()
}
return streamer
}
// RegisterClient registers an incoming streamer constructor
func (r *Registry) RegisterClientFunc(stream string, f func(*Peer, string, bool) (Client, error)) {
r.clientMu.Lock()
defer r.clientMu.Unlock()
r.clientFuncs[stream] = f
}
// RegisterServer registers an outgoing streamer constructor
func (r *Registry) RegisterServerFunc(stream string, f func(*Peer, string, bool) (Server, error)) {
r.serverMu.Lock()
defer r.serverMu.Unlock()
r.serverFuncs[stream] = f
}
// GetClient accessor for incoming streamer constructors
func (r *Registry) GetClientFunc(stream string) (func(*Peer, string, bool) (Client, error), error) {
r.clientMu.RLock()
defer r.clientMu.RUnlock()
f := r.clientFuncs[stream]
if f == nil {
return nil, fmt.Errorf("stream %v not registered", stream)
}
return f, nil
}
// GetServer accessor for incoming streamer constructors
func (r *Registry) GetServerFunc(stream string) (func(*Peer, string, bool) (Server, error), error) {
r.serverMu.RLock()
defer r.serverMu.RUnlock()
f := r.serverFuncs[stream]
if f == nil {
return nil, fmt.Errorf("stream %v not registered", stream)
}
return f, nil
}
func (r *Registry) RequestSubscription(peerId enode.ID, s Stream, h *Range, prio uint8) error {
// check if the stream is registered
if _, err := r.GetServerFunc(s.Name); err != nil {
return err
}
peer := r.getPeer(peerId)
if peer == nil {
return fmt.Errorf("peer not found %v", peerId)
}
if _, err := peer.getServer(s); err != nil {
if e, ok := err.(*notFoundError); ok && e.t == "server" {
// request subscription only if the server for this stream is not created
log.Debug("RequestSubscription ", "peer", peerId, "stream", s, "history", h)
return peer.Send(context.TODO(), &RequestSubscriptionMsg{
Stream: s,
History: h,
Priority: prio,
})
}
return err
}
log.Trace("RequestSubscription: already subscribed", "peer", peerId, "stream", s, "history", h)
return nil
}
// Subscribe initiates the streamer
func (r *Registry) Subscribe(peerId enode.ID, s Stream, h *Range, priority uint8) error {
// check if the stream is registered
if _, err := r.GetClientFunc(s.Name); err != nil {
return err
}
peer := r.getPeer(peerId)
if peer == nil {
return fmt.Errorf("peer not found %v", peerId)
}
var to uint64
if !s.Live && h != nil {
to = h.To
}
err := peer.setClientParams(s, newClientParams(priority, to))
if err != nil {
return err
}
if s.Live && h != nil {
if err := peer.setClientParams(
getHistoryStream(s),
newClientParams(getHistoryPriority(priority), h.To),
); err != nil {
return err
}
}
msg := &SubscribeMsg{
Stream: s,
History: h,
Priority: priority,
}
log.Debug("Subscribe ", "peer", peerId, "stream", s, "history", h)
return peer.SendPriority(context.TODO(), msg, priority)
}
func (r *Registry) Unsubscribe(peerId enode.ID, s Stream) error {
peer := r.getPeer(peerId)
if peer == nil {
return fmt.Errorf("peer not found %v", peerId)
}
msg := &UnsubscribeMsg{
Stream: s,
}
log.Debug("Unsubscribe ", "peer", peerId, "stream", s)
if err := peer.Send(context.TODO(), msg); err != nil {
return err
}
return peer.removeClient(s)
}
// Quit sends the QuitMsg to the peer to remove the
// stream peer client and terminate the streaming.
func (r *Registry) Quit(peerId enode.ID, s Stream) error {
peer := r.getPeer(peerId)
if peer == nil {
log.Debug("stream quit: peer not found", "peer", peerId, "stream", s)
// if the peer is not found, abort the request
return nil
}
msg := &QuitMsg{
Stream: s,
}
log.Debug("Quit ", "peer", peerId, "stream", s)
return peer.Send(context.TODO(), msg)
}
func (r *Registry) NodeInfo() interface{} {
return nil
}
func (r *Registry) PeerInfo(id enode.ID) interface{} {
return nil
}
func (r *Registry) Close() error {
return r.intervalsStore.Close()
}
func (r *Registry) getPeer(peerId enode.ID) *Peer {
r.peersMu.RLock()
defer r.peersMu.RUnlock()
return r.peers[peerId]
}
func (r *Registry) setPeer(peer *Peer) {
r.peersMu.Lock()
r.peers[peer.ID()] = peer
metrics.GetOrRegisterGauge("registry.peers", nil).Update(int64(len(r.peers)))
r.peersMu.Unlock()
}
func (r *Registry) deletePeer(peer *Peer) {
r.peersMu.Lock()
delete(r.peers, peer.ID())
metrics.GetOrRegisterGauge("registry.peers", nil).Update(int64(len(r.peers)))
r.peersMu.Unlock()
}
func (r *Registry) peersCount() (c int) {
r.peersMu.Lock()
c = len(r.peers)
r.peersMu.Unlock()
return
}
// Run protocol run function
func (r *Registry) Run(p *network.BzzPeer) error {
sp := NewPeer(p.Peer, r)
r.setPeer(sp)
defer r.deletePeer(sp)
defer close(sp.quit)
defer sp.close()
if r.doRetrieve {
err := r.Subscribe(p.ID(), NewStream(swarmChunkServerStreamName, "", false), nil, Top)
if err != nil {
return err
}
}
return sp.Run(sp.HandleMsg)
}
// updateSyncing subscribes to SYNC streams by iterating over the
// kademlia connections and bins. If there are existing SYNC streams
// and they are no longer required after iteration, request to Quit
// them will be send to appropriate peers.
func (r *Registry) updateSyncing() {
kad := r.delivery.kad
// map of all SYNC streams for all peers
// used at the and of the function to remove servers
// that are not needed anymore
subs := make(map[enode.ID]map[Stream]struct{})
r.peersMu.RLock()
for id, peer := range r.peers {
peer.serverMu.RLock()
for stream := range peer.servers {
if stream.Name == "SYNC" {
if _, ok := subs[id]; !ok {
subs[id] = make(map[Stream]struct{})
}
subs[id][stream] = struct{}{}
}
}
peer.serverMu.RUnlock()
}
r.peersMu.RUnlock()
// request subscriptions for all nodes and bins
kad.EachBin(r.addr[:], pot.DefaultPof(256), 0, func(p *network.Peer, bin int) bool {
log.Debug(fmt.Sprintf("Requesting subscription by: registry %s from peer %s for bin: %d", r.addr, p.ID(), bin))
// bin is always less then 256 and it is safe to convert it to type uint8
stream := NewStream("SYNC", FormatSyncBinKey(uint8(bin)), true)
if streams, ok := subs[p.ID()]; ok {
// delete live and history streams from the map, so that it won't be removed with a Quit request
delete(streams, stream)
delete(streams, getHistoryStream(stream))
}
err := r.RequestSubscription(p.ID(), stream, NewRange(0, 0), High)
if err != nil {
log.Debug("Request subscription", "err", err, "peer", p.ID(), "stream", stream)
return false
}
return true
})
// remove SYNC servers that do not need to be subscribed
for id, streams := range subs {
if len(streams) == 0 {
continue
}
peer := r.getPeer(id)
if peer == nil {
continue
}
for stream := range streams {
log.Debug("Remove sync server", "peer", id, "stream", stream)
err := r.Quit(peer.ID(), stream)
if err != nil && err != p2p.ErrShuttingDown {
log.Error("quit", "err", err, "peer", peer.ID(), "stream", stream)
}
}
}
}
func (r *Registry) runProtocol(p *p2p.Peer, rw p2p.MsgReadWriter) error {
peer := protocols.NewPeer(p, rw, Spec)
bp := network.NewBzzPeer(peer)
np := network.NewPeer(bp, r.delivery.kad)
r.delivery.kad.On(np)
defer r.delivery.kad.Off(np)
return r.Run(bp)
}
// HandleMsg is the message handler that delegates incoming messages
func (p *Peer) HandleMsg(ctx context.Context, msg interface{}) error {
switch msg := msg.(type) {
case *SubscribeMsg:
return p.handleSubscribeMsg(ctx, msg)
case *SubscribeErrorMsg:
return p.handleSubscribeErrorMsg(msg)
case *UnsubscribeMsg:
return p.handleUnsubscribeMsg(msg)
case *OfferedHashesMsg:
return p.handleOfferedHashesMsg(ctx, msg)
case *TakeoverProofMsg:
return p.handleTakeoverProofMsg(ctx, msg)
case *WantedHashesMsg:
return p.handleWantedHashesMsg(ctx, msg)
case *ChunkDeliveryMsg:
return p.streamer.delivery.handleChunkDeliveryMsg(ctx, p, msg)
case *RetrieveRequestMsg:
return p.streamer.delivery.handleRetrieveRequestMsg(ctx, p, msg)
case *RequestSubscriptionMsg:
return p.handleRequestSubscription(ctx, msg)
case *QuitMsg:
return p.handleQuitMsg(msg)
default:
return fmt.Errorf("unknown message type: %T", msg)
}
}
type server struct {
Server
stream Stream
priority uint8
currentBatch []byte
}
// Server interface for outgoing peer Streamer
type Server interface {
SetNextBatch(uint64, uint64) (hashes []byte, from uint64, to uint64, proof *HandoverProof, err error)
GetData(context.Context, []byte) ([]byte, error)
Close()
}
type client struct {
Client
stream Stream
priority uint8
sessionAt uint64
to uint64
next chan error
quit chan struct{}
intervalsKey string
intervalsStore state.Store
}
func peerStreamIntervalsKey(p *Peer, s Stream) string {
return p.ID().String() + s.String()
}
func (c client) AddInterval(start, end uint64) (err error) {
i := &intervals.Intervals{}
err = c.intervalsStore.Get(c.intervalsKey, i)
if err != nil {
return err
}
i.Add(start, end)
return c.intervalsStore.Put(c.intervalsKey, i)
}
func (c client) NextInterval() (start, end uint64, err error) {
i := &intervals.Intervals{}
err = c.intervalsStore.Get(c.intervalsKey, i)
if err != nil {
return 0, 0, err
}
start, end = i.Next()
return start, end, nil
}
// Client interface for incoming peer Streamer
type Client interface {
NeedData(context.Context, []byte) func(context.Context) error
BatchDone(Stream, uint64, []byte, []byte) func() (*TakeoverProof, error)
Close()
}
func (c *client) nextBatch(from uint64) (nextFrom uint64, nextTo uint64) {
if c.to > 0 && from >= c.to {
return 0, 0
}
if c.stream.Live {
return from, 0
} else if from >= c.sessionAt {
if c.to > 0 {
return from, c.to
}
return from, math.MaxUint64
}
nextFrom, nextTo, err := c.NextInterval()
if err != nil {
log.Error("next intervals", "stream", c.stream)
return
}
if nextTo > c.to {
nextTo = c.to
}
if nextTo == 0 {
nextTo = c.sessionAt
}
return
}
func (c *client) batchDone(p *Peer, req *OfferedHashesMsg, hashes []byte) error {
if tf := c.BatchDone(req.Stream, req.From, hashes, req.Root); tf != nil {
tp, err := tf()
if err != nil {
return err
}
if err := p.SendPriority(context.TODO(), tp, c.priority); err != nil {
return err
}
if c.to > 0 && tp.Takeover.End >= c.to {
return p.streamer.Unsubscribe(p.Peer.ID(), req.Stream)
}
return nil
}
// TODO: make a test case for testing if the interval is added when the batch is done
if err := c.AddInterval(req.From, req.To); err != nil {
return err
}
return nil
}
func (c *client) close() {
select {
case <-c.quit:
default:
close(c.quit)
}
c.Close()
}
// clientParams store parameters for the new client
// between a subscription and initial offered hashes request handling.
type clientParams struct {
priority uint8
to uint64
// signal when the client is created
clientCreatedC chan struct{}
}
func newClientParams(priority uint8, to uint64) *clientParams {
return &clientParams{
priority: priority,
to: to,
clientCreatedC: make(chan struct{}),
}
}
func (c *clientParams) waitClient(ctx context.Context) error {
select {
case <-ctx.Done():
return ctx.Err()
case <-c.clientCreatedC:
return nil
}
}
func (c *clientParams) clientCreated() {
close(c.clientCreatedC)
}
// Spec is the spec of the streamer protocol
var Spec = &protocols.Spec{
Name: "stream",
Version: 6,
MaxMsgSize: 10 * 1024 * 1024,
Messages: []interface{}{
UnsubscribeMsg{},
OfferedHashesMsg{},
WantedHashesMsg{},
TakeoverProofMsg{},
SubscribeMsg{},
RetrieveRequestMsg{},
ChunkDeliveryMsg{},
SubscribeErrorMsg{},
RequestSubscriptionMsg{},
QuitMsg{},
},
}
func (r *Registry) Protocols() []p2p.Protocol {
return []p2p.Protocol{
{
Name: Spec.Name,
Version: Spec.Version,
Length: Spec.Length(),
Run: r.runProtocol,
// NodeInfo: ,
// PeerInfo: ,
},
}
}
func (r *Registry) APIs() []rpc.API {
return []rpc.API{
{
Namespace: "stream",
Version: "3.0",
Service: r.api,
Public: true,
},
}
}
func (r *Registry) Start(server *p2p.Server) error {
log.Info("Streamer started")
return nil
}
func (r *Registry) Stop() error {
return nil
}
type Range struct {
From, To uint64
}
func NewRange(from, to uint64) *Range {
return &Range{
From: from,
To: to,
}
}
func (r *Range) String() string {
return fmt.Sprintf("%v-%v", r.From, r.To)
}
func getHistoryPriority(priority uint8) uint8 {
if priority == 0 {
return 0
}
return priority - 1
}
func getHistoryStream(s Stream) Stream {
return NewStream(s.Name, s.Key, false)
}
type API struct {
streamer *Registry
}
func NewAPI(r *Registry) *API {
return &API{
streamer: r,
}
}
func (api *API) SubscribeStream(peerId enode.ID, s Stream, history *Range, priority uint8) error {
return api.streamer.Subscribe(peerId, s, history, priority)
}
func (api *API) UnsubscribeStream(peerId enode.ID, s Stream) error {
return api.streamer.Unsubscribe(peerId, s)
}