go-ethereum/swarm/network/protocol.go
Lewis Marshall da6d15da4c p2p/simulations: Drop adapters.NodeId in favour of discover.NodeID
Signed-off-by: Lewis Marshall <lewis@lmars.net>
2017-05-27 16:11:03 +01:00

359 lines
9.4 KiB
Go

// Copyright 2016 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 network
import (
"context"
"errors"
"fmt"
"net"
"sync"
"time"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/p2p/discover"
"github.com/ethereum/go-ethereum/p2p/protocols"
"github.com/ethereum/go-ethereum/rpc"
)
const (
NetworkId = 322 // BZZ in l33t
ProtocolMaxMsgSize = 10 * 1024 * 1024
)
var BzzHandshakeSpec = &protocols.Spec{
Name: "bzz",
Version: 1,
MaxMsgSize: 10 * 1024 * 1024,
Messages: []interface{}{
bzzHandshake{},
},
}
var DiscoverySpec = &protocols.Spec{
Name: "hive",
Version: 1,
MaxMsgSize: 10 * 1024 * 1024,
Messages: []interface{}{
peersMsg{},
getPeersMsg{},
subPeersMsg{},
},
}
// the Addr interface that peerPool needs
type Addr interface {
OverlayPeer
Over() []byte
Under() []byte
String() string
Update(OverlayAddr) OverlayAddr
}
// Peer interface represents an live peer connection
type Peer interface {
Addr // the address of a peer
Conn // the live connection (protocols.Peer)
LastActive() time.Time // last time active
}
// Conn interface represents an live peer connection
type Conn interface {
ID() discover.NodeID // the key that uniquely identifies the Node for the peerPool
Handshake(context.Context, interface{}) (interface{}, error) // can send messages
Send(interface{}) error // can send messages
Drop(error) // disconnect this peer
Run(func(interface{}) error) error // the run function to run a protocol
Off() OverlayAddr
}
// TODO: implement store for exec nodes
type StateStore interface {
Load(string) ([]byte, error)
Save(string, []byte) error
}
// BzzConfig captures the config params used by the hive
type BzzConfig struct {
OverlayAddr []byte
UnderlayAddr []byte
HiveParams *HiveParams
}
// Bzz is the swarm protocol bundle
type Bzz struct {
Hive *Hive
localAddr *bzzAddr
mtx sync.Mutex
handshakes map[discover.NodeID]*bzzHandshake
}
// NewBzz is the swarm protocol constructor
func NewBzz(config *BzzConfig, kad Overlay, store StateStore) *Bzz {
return &Bzz{
Hive: NewHive(config.HiveParams, kad, store),
localAddr: &bzzAddr{config.OverlayAddr, config.UnderlayAddr},
handshakes: make(map[discover.NodeID]*bzzHandshake),
}
}
// Bzz implements the node.Service interface, offers Protocols
// * handshake/hive
// * discovery
func (b *Bzz) Protocols() []p2p.Protocol {
return []p2p.Protocol{
{
Name: BzzHandshakeSpec.Name,
Version: BzzHandshakeSpec.Version,
Length: BzzHandshakeSpec.Length(),
Run: b.runHandshake,
},
{
Name: DiscoverySpec.Name,
Version: DiscoverySpec.Version,
Length: DiscoverySpec.Length(),
Run: b.runProtocol(DiscoverySpec, b.Hive.Run),
NodeInfo: b.Hive.NodeInfo,
PeerInfo: b.Hive.PeerInfo,
},
}
}
// Bzz implements the node.Service interface, offers APIs:
// * hive
func (b *Bzz) APIs() []rpc.API {
return []rpc.API{{
Namespace: "hive",
Version: "1.0",
Service: b.Hive,
}}
}
func (b *Bzz) Start(server *p2p.Server) error {
return b.Hive.Start(server)
}
func (b *Bzz) Stop() error {
b.Hive.Stop()
return nil
}
func (b *Bzz) runHandshake(p *p2p.Peer, rw p2p.MsgReadWriter) error {
handshake := b.getHandshake(p.ID())
defer b.removeHandshake(p.ID())
if err := handshake.Perform(p, rw); err != nil {
log.Error("handshake failed", "peer", p.ID(), "err", err)
return err
}
// fail if we get another handshake
msg, err := rw.ReadMsg()
if err != nil {
return err
}
msg.Discard()
return errors.New("received multiple handshakes")
}
func (b *Bzz) runProtocol(spec *protocols.Spec, run func(*bzzPeer) error) func(*p2p.Peer, p2p.MsgReadWriter) error {
return func(p *p2p.Peer, rw p2p.MsgReadWriter) error {
// wait for the bzz protocol to perform the handshake
handshake := b.getHandshake(p.ID())
if err := handshake.Wait(); err != nil {
return err
}
// the handshake has succeeded so run the service
peer := &bzzPeer{
Peer: protocols.NewPeer(p, rw, spec),
localAddr: b.localAddr,
bzzAddr: handshake.peerAddr,
}
return run(peer)
}
}
func (b *Bzz) removeHandshake(peerID discover.NodeID) {
b.mtx.Lock()
defer b.mtx.Unlock()
delete(b.handshakes, peerID)
}
func (b *Bzz) getHandshake(peerID discover.NodeID) *bzzHandshake {
b.mtx.Lock()
defer b.mtx.Unlock()
handshake, ok := b.handshakes[peerID]
if !ok {
handshake = &bzzHandshake{
Version: uint64(BzzHandshakeSpec.Version),
NetworkId: uint64(NetworkId),
Addr: b.localAddr,
done: make(chan struct{}),
}
b.handshakes[peerID] = handshake
}
return handshake
}
// bzzPeer is the bzz protocol view of a protocols.Peer (itself an extension of p2p.Peer)
// implements the Peer interface and all interfaces Peer implements: Addr, OverlayPeer
type bzzPeer struct {
*protocols.Peer // represents the connection for online peers
localAddr *bzzAddr // local Peers address
*bzzAddr // remote address -> implements Addr interface = protocols.Peer
lastActive time.Time // time is updated whenever mutexes are releasing
}
func newBzzPeer(p *protocols.Peer, over, under []byte) *bzzPeer {
return &bzzPeer{
Peer: p,
localAddr: &bzzAddr{over, under},
}
}
// Off returns the overlay peer record for offline persistance
func (self *bzzPeer) Off() OverlayAddr {
return self.bzzAddr
}
// LastActive returns the time the peer was last active
func (self *bzzPeer) LastActive() time.Time {
return self.lastActive
}
/*
Handshake
* Version: 8 byte integer version of the protocol
* NetworkId: 8 byte integer network identifier
* Addr: the address advertised by the node including underlay and overlay connecctions
*/
type bzzHandshake struct {
Version uint64
NetworkId uint64
Addr *bzzAddr
// peerAddr is the address received in the peer handshake
peerAddr *bzzAddr
done chan struct{}
err error
}
func (self *bzzHandshake) String() string {
return fmt.Sprintf("Handshake: Version: %v, NetworkId: %v, Addr: %v", self.Version, self.NetworkId, self.Addr)
}
const bzzHandshakeTimeout = time.Second
func (self *bzzHandshake) Perform(p *p2p.Peer, rw p2p.MsgReadWriter) (err error) {
defer func() {
self.err = err
close(self.done)
}()
peer := protocols.NewPeer(p, rw, BzzHandshakeSpec)
ctx, cancel := context.WithTimeout(context.Background(), bzzHandshakeTimeout)
defer cancel()
hs, err := peer.Handshake(ctx, self)
if err != nil {
return err
}
rhs := hs.(*bzzHandshake)
if rhs.NetworkId != self.NetworkId {
return fmt.Errorf("network id mismatch %d (!= %d)", rhs.NetworkId, self.NetworkId)
}
if rhs.Version != self.Version {
return fmt.Errorf("version mismatch %d (!= %d)", rhs.Version, self.Version)
}
self.peerAddr = rhs.Addr
return nil
}
func (self *bzzHandshake) Wait() error {
select {
case <-self.done:
return self.err
case <-time.After(bzzHandshakeTimeout):
return errors.New("timed out waiting for bzz handshake")
}
}
// bzzAddr implements the PeerAddr interface
type bzzAddr struct {
OAddr []byte
UAddr []byte
}
// implements OverlayPeer interface to be used in pot package
func (self *bzzAddr) Address() []byte {
return self.OAddr
}
// Over returns the overlay address
func (self *bzzAddr) Over() []byte {
return self.OAddr
}
// Under retrun the underlay address
func (self *bzzAddr) Under() []byte {
return self.UAddr
}
func (self *bzzAddr) Update(a OverlayAddr) OverlayAddr {
return &bzzAddr{self.OAddr, a.(Addr).Under()}
}
func (self *bzzAddr) String() string {
return fmt.Sprintf("%x <%s>", self.OAddr, self.UAddr)
}
// RandomAddr is a utility method generating an address from a public key
func RandomAddr() *bzzAddr {
key, err := crypto.GenerateKey()
if err != nil {
panic("unable to generate key")
}
pubkey := crypto.FromECDSAPub(&key.PublicKey)
var id discover.NodeID
copy(id[:], pubkey[1:])
return &bzzAddr{
OAddr: crypto.Keccak256(pubkey[1:]),
UAddr: id[:],
}
}
// NewNodeIDFromAddr transforms the underlay address to an adapters.NodeID
func NewNodeIDFromAddr(addr Addr) discover.NodeID {
return discover.MustBytesID(addr.Under())
}
// NewAddrFromNodeID constucts a bzzAddr from a discover.NodeID
// the overlay address is derived as the hash of the nodeID
func NewAddrFromNodeID(id discover.NodeID) *bzzAddr {
return &bzzAddr{
OAddr: ToOverlayAddr(id.Bytes()),
UAddr: []byte(discover.NewNode(id, net.IP{127, 0, 0, 1}, 30303, 30303).String()),
}
}
// ToOverlayAddr creates an overlayaddress from NodeID
func ToOverlayAddr(id []byte) []byte {
return crypto.Keccak256(id)
}