p2p, p2p/discover, p2p/discv5: implement UDP port sharing (#15200)

This commit affects p2p/discv5 "topic discovery" by running it on
the same UDP port where the old discovery works. This is realized
by giving an "unhandled" packet channel to the old v4 discovery
packet handler where all invalid packets are sent. These packets
are then processed by v5. v5 packets are always invalid when
interpreted by v4 and vice versa. This is ensured by adding one
to the first byte of the packet hash in v5 packets.

DiscoveryV5Bootnodes is also changed to point to new bootnodes
that are implementing the changed packet format with modified
hash. Existing and new v5 bootnodes are both running on different
ports ATM.
This commit is contained in:
Felföldi Zsolt 2018-01-22 13:38:34 +01:00 committed by Felix Lange
parent 02aeb3d766
commit 92580d69d3
17 changed files with 150 additions and 91 deletions

View File

@ -21,6 +21,7 @@ import (
"crypto/ecdsa"
"flag"
"fmt"
"net"
"os"
"github.com/ethereum/go-ethereum/cmd/utils"
@ -96,12 +97,32 @@ func main() {
}
}
addr, err := net.ResolveUDPAddr("udp", *listenAddr)
if err != nil {
utils.Fatalf("-ResolveUDPAddr: %v", err)
}
conn, err := net.ListenUDP("udp", addr)
if err != nil {
utils.Fatalf("-ListenUDP: %v", err)
}
realaddr := conn.LocalAddr().(*net.UDPAddr)
if natm != nil {
if !realaddr.IP.IsLoopback() {
go nat.Map(natm, nil, "udp", realaddr.Port, realaddr.Port, "ethereum discovery")
}
// TODO: react to external IP changes over time.
if ext, err := natm.ExternalIP(); err == nil {
realaddr = &net.UDPAddr{IP: ext, Port: realaddr.Port}
}
}
if *runv5 {
if _, err := discv5.ListenUDP(nodeKey, *listenAddr, natm, "", restrictList); err != nil {
if _, err := discv5.ListenUDP(nodeKey, conn, realaddr, "", restrictList); err != nil {
utils.Fatalf("%v", err)
}
} else {
if _, err := discover.ListenUDP(nodeKey, *listenAddr, natm, "", restrictList); err != nil {
if _, err := discover.ListenUDP(nodeKey, conn, realaddr, nil, "", restrictList); err != nil {
utils.Fatalf("%v", err)
}
}

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@ -223,7 +223,6 @@ func newFaucet(genesis *core.Genesis, port int, enodes []*discv5.Node, network u
NoDiscovery: true,
DiscoveryV5: true,
ListenAddr: fmt.Sprintf(":%d", port),
DiscoveryV5Addr: fmt.Sprintf(":%d", port+1),
MaxPeers: 25,
BootstrapNodesV5: enodes,
},

View File

@ -636,14 +636,6 @@ func setListenAddress(ctx *cli.Context, cfg *p2p.Config) {
}
}
// setDiscoveryV5Address creates a UDP listening address string from set command
// line flags for the V5 discovery protocol.
func setDiscoveryV5Address(ctx *cli.Context, cfg *p2p.Config) {
if ctx.GlobalIsSet(ListenPortFlag.Name) {
cfg.DiscoveryV5Addr = fmt.Sprintf(":%d", ctx.GlobalInt(ListenPortFlag.Name)+1)
}
}
// setNAT creates a port mapper from command line flags.
func setNAT(ctx *cli.Context, cfg *p2p.Config) {
if ctx.GlobalIsSet(NATFlag.Name) {
@ -794,7 +786,6 @@ func SetP2PConfig(ctx *cli.Context, cfg *p2p.Config) {
setNodeKey(ctx, cfg)
setNAT(ctx, cfg)
setListenAddress(ctx, cfg)
setDiscoveryV5Address(ctx, cfg)
setBootstrapNodes(ctx, cfg)
setBootstrapNodesV5(ctx, cfg)
@ -830,7 +821,6 @@ func SetP2PConfig(ctx *cli.Context, cfg *p2p.Config) {
// --dev mode can't use p2p networking.
cfg.MaxPeers = 0
cfg.ListenAddr = ":0"
cfg.DiscoveryV5Addr = ":0"
cfg.NoDiscovery = true
cfg.DiscoveryV5 = false
}

View File

@ -221,9 +221,8 @@ func (s *LightEthereum) Start(srvr *p2p.Server) error {
s.startBloomHandlers()
log.Warn("Light client mode is an experimental feature")
s.netRPCService = ethapi.NewPublicNetAPI(srvr, s.networkId)
// search the topic belonging to the oldest supported protocol because
// servers always advertise all supported protocols
protocolVersion := ClientProtocolVersions[len(ClientProtocolVersions)-1]
// clients are searching for the first advertised protocol in the list
protocolVersion := AdvertiseProtocolVersions[0]
s.serverPool.start(srvr, lesTopic(s.blockchain.Genesis().Hash(), protocolVersion))
s.protocolManager.Start()
return nil

View File

@ -41,8 +41,9 @@ const (
// Supported versions of the les protocol (first is primary)
var (
ClientProtocolVersions = []uint{lpv2, lpv1}
ServerProtocolVersions = []uint{lpv2, lpv1}
ClientProtocolVersions = []uint{lpv2, lpv1}
ServerProtocolVersions = []uint{lpv2, lpv1}
AdvertiseProtocolVersions = []uint{lpv2} // clients are searching for the first advertised protocol in the list
)
// Number of implemented message corresponding to different protocol versions.

View File

@ -56,8 +56,8 @@ func NewLesServer(eth *eth.Ethereum, config *eth.Config) (*LesServer, error) {
return nil, err
}
lesTopics := make([]discv5.Topic, len(ServerProtocolVersions))
for i, pv := range ServerProtocolVersions {
lesTopics := make([]discv5.Topic, len(AdvertiseProtocolVersions))
for i, pv := range AdvertiseProtocolVersions {
lesTopics[i] = lesTopic(eth.BlockChain().Genesis().Hash(), pv)
}

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@ -116,7 +116,6 @@ func NewNode(datadir string, config *NodeConfig) (stack *Node, _ error) {
P2P: p2p.Config{
NoDiscovery: true,
DiscoveryV5: true,
DiscoveryV5Addr: ":0",
BootstrapNodesV5: config.BootstrapNodes.nodes,
ListenAddr: ":0",
NAT: nat.Any(),

View File

@ -41,10 +41,9 @@ var DefaultConfig = Config{
WSPort: DefaultWSPort,
WSModules: []string{"net", "web3"},
P2P: p2p.Config{
ListenAddr: ":30303",
DiscoveryV5Addr: ":30304",
MaxPeers: 25,
NAT: nat.Any(),
ListenAddr: ":30303",
MaxPeers: 25,
NAT: nat.Any(),
},
}

View File

@ -210,17 +210,15 @@ type reply struct {
matched chan<- bool
}
// ReadPacket is sent to the unhandled channel when it could not be processed
type ReadPacket struct {
Data []byte
Addr *net.UDPAddr
}
// ListenUDP returns a new table that listens for UDP packets on laddr.
func ListenUDP(priv *ecdsa.PrivateKey, laddr string, natm nat.Interface, nodeDBPath string, netrestrict *netutil.Netlist) (*Table, error) {
addr, err := net.ResolveUDPAddr("udp", laddr)
if err != nil {
return nil, err
}
conn, err := net.ListenUDP("udp", addr)
if err != nil {
return nil, err
}
tab, _, err := newUDP(priv, conn, natm, nodeDBPath, netrestrict)
func ListenUDP(priv *ecdsa.PrivateKey, conn conn, realaddr *net.UDPAddr, unhandled chan ReadPacket, nodeDBPath string, netrestrict *netutil.Netlist) (*Table, error) {
tab, _, err := newUDP(priv, conn, realaddr, unhandled, nodeDBPath, netrestrict)
if err != nil {
return nil, err
}
@ -228,7 +226,7 @@ func ListenUDP(priv *ecdsa.PrivateKey, laddr string, natm nat.Interface, nodeDBP
return tab, nil
}
func newUDP(priv *ecdsa.PrivateKey, c conn, natm nat.Interface, nodeDBPath string, netrestrict *netutil.Netlist) (*Table, *udp, error) {
func newUDP(priv *ecdsa.PrivateKey, c conn, realaddr *net.UDPAddr, unhandled chan ReadPacket, nodeDBPath string, netrestrict *netutil.Netlist) (*Table, *udp, error) {
udp := &udp{
conn: c,
priv: priv,
@ -237,16 +235,6 @@ func newUDP(priv *ecdsa.PrivateKey, c conn, natm nat.Interface, nodeDBPath strin
gotreply: make(chan reply),
addpending: make(chan *pending),
}
realaddr := c.LocalAddr().(*net.UDPAddr)
if natm != nil {
if !realaddr.IP.IsLoopback() {
go nat.Map(natm, udp.closing, "udp", realaddr.Port, realaddr.Port, "ethereum discovery")
}
// TODO: react to external IP changes over time.
if ext, err := natm.ExternalIP(); err == nil {
realaddr = &net.UDPAddr{IP: ext, Port: realaddr.Port}
}
}
// TODO: separate TCP port
udp.ourEndpoint = makeEndpoint(realaddr, uint16(realaddr.Port))
tab, err := newTable(udp, PubkeyID(&priv.PublicKey), realaddr, nodeDBPath)
@ -256,7 +244,7 @@ func newUDP(priv *ecdsa.PrivateKey, c conn, natm nat.Interface, nodeDBPath strin
udp.Table = tab
go udp.loop()
go udp.readLoop()
go udp.readLoop(unhandled)
return udp.Table, udp, nil
}
@ -492,8 +480,11 @@ func encodePacket(priv *ecdsa.PrivateKey, ptype byte, req interface{}) ([]byte,
}
// readLoop runs in its own goroutine. it handles incoming UDP packets.
func (t *udp) readLoop() {
func (t *udp) readLoop(unhandled chan ReadPacket) {
defer t.conn.Close()
if unhandled != nil {
defer close(unhandled)
}
// Discovery packets are defined to be no larger than 1280 bytes.
// Packets larger than this size will be cut at the end and treated
// as invalid because their hash won't match.
@ -509,7 +500,12 @@ func (t *udp) readLoop() {
log.Debug("UDP read error", "err", err)
return
}
t.handlePacket(from, buf[:nbytes])
if t.handlePacket(from, buf[:nbytes]) != nil && unhandled != nil {
select {
case unhandled <- ReadPacket{buf[:nbytes], from}:
default:
}
}
}
}

View File

@ -70,7 +70,8 @@ func newUDPTest(t *testing.T) *udpTest {
remotekey: newkey(),
remoteaddr: &net.UDPAddr{IP: net.IP{10, 0, 1, 99}, Port: 30303},
}
test.table, test.udp, _ = newUDP(test.localkey, test.pipe, nil, "", nil)
realaddr := test.pipe.LocalAddr().(*net.UDPAddr)
test.table, test.udp, _ = newUDP(test.localkey, test.pipe, realaddr, nil, "", nil)
return test
}

View File

@ -29,7 +29,6 @@ import (
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/crypto/sha3"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/p2p/nat"
"github.com/ethereum/go-ethereum/p2p/netutil"
"github.com/ethereum/go-ethereum/rlp"
)
@ -134,7 +133,7 @@ type timeoutEvent struct {
node *Node
}
func newNetwork(conn transport, ourPubkey ecdsa.PublicKey, natm nat.Interface, dbPath string, netrestrict *netutil.Netlist) (*Network, error) {
func newNetwork(conn transport, ourPubkey ecdsa.PublicKey, dbPath string, netrestrict *netutil.Netlist) (*Network, error) {
ourID := PubkeyID(&ourPubkey)
var db *nodeDB

View File

@ -28,7 +28,7 @@ import (
func TestNetwork_Lookup(t *testing.T) {
key, _ := crypto.GenerateKey()
network, err := newNetwork(lookupTestnet, key.PublicKey, nil, "", nil)
network, err := newNetwork(lookupTestnet, key.PublicKey, "", nil)
if err != nil {
t.Fatal(err)
}

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@ -282,7 +282,7 @@ func (s *simulation) launchNode(log bool) *Network {
addr := &net.UDPAddr{IP: ip, Port: 30303}
transport := &simTransport{joinTime: time.Now(), sender: id, senderAddr: addr, sim: s, priv: key}
net, err := newNetwork(transport, key.PublicKey, nil, "<no database>", nil)
net, err := newNetwork(transport, key.PublicKey, "<no database>", nil)
if err != nil {
panic("cannot launch new node: " + err.Error())
}

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@ -642,7 +642,7 @@ func (s *ticketStore) gotTopicNodes(from *Node, hash common.Hash, nodes []rpcNod
if ip.IsUnspecified() || ip.IsLoopback() {
ip = from.IP
}
n := NewNode(node.ID, ip, node.UDP-1, node.TCP-1) // subtract one from port while discv5 is running in test mode on UDPport+1
n := NewNode(node.ID, ip, node.UDP, node.TCP)
select {
case chn <- n:
default:

View File

@ -37,7 +37,7 @@ const Version = 4
// Errors
var (
errPacketTooSmall = errors.New("too small")
errBadHash = errors.New("bad hash")
errBadPrefix = errors.New("bad prefix")
errExpired = errors.New("expired")
errUnsolicitedReply = errors.New("unsolicited reply")
errUnknownNode = errors.New("unknown node")
@ -145,10 +145,11 @@ type (
}
)
const (
macSize = 256 / 8
sigSize = 520 / 8
headSize = macSize + sigSize // space of packet frame data
var (
versionPrefix = []byte("temporary discovery v5")
versionPrefixSize = len(versionPrefix)
sigSize = 520 / 8
headSize = versionPrefixSize + sigSize // space of packet frame data
)
// Neighbors replies are sent across multiple packets to
@ -237,12 +238,12 @@ type udp struct {
}
// ListenUDP returns a new table that listens for UDP packets on laddr.
func ListenUDP(priv *ecdsa.PrivateKey, laddr string, natm nat.Interface, nodeDBPath string, netrestrict *netutil.Netlist) (*Network, error) {
transport, err := listenUDP(priv, laddr)
func ListenUDP(priv *ecdsa.PrivateKey, conn conn, realaddr *net.UDPAddr, nodeDBPath string, netrestrict *netutil.Netlist) (*Network, error) {
transport, err := listenUDP(priv, conn, realaddr)
if err != nil {
return nil, err
}
net, err := newNetwork(transport, priv.PublicKey, natm, nodeDBPath, netrestrict)
net, err := newNetwork(transport, priv.PublicKey, nodeDBPath, netrestrict)
if err != nil {
return nil, err
}
@ -251,16 +252,8 @@ func ListenUDP(priv *ecdsa.PrivateKey, laddr string, natm nat.Interface, nodeDBP
return net, nil
}
func listenUDP(priv *ecdsa.PrivateKey, laddr string) (*udp, error) {
addr, err := net.ResolveUDPAddr("udp", laddr)
if err != nil {
return nil, err
}
conn, err := net.ListenUDP("udp", addr)
if err != nil {
return nil, err
}
return &udp{conn: conn, priv: priv, ourEndpoint: makeEndpoint(addr, uint16(addr.Port))}, nil
func listenUDP(priv *ecdsa.PrivateKey, conn conn, realaddr *net.UDPAddr) (*udp, error) {
return &udp{conn: conn, priv: priv, ourEndpoint: makeEndpoint(realaddr, uint16(realaddr.Port))}, nil
}
func (t *udp) localAddr() *net.UDPAddr {
@ -372,11 +365,9 @@ func encodePacket(priv *ecdsa.PrivateKey, ptype byte, req interface{}) (p, hash
log.Error(fmt.Sprint("could not sign packet:", err))
return nil, nil, err
}
copy(packet[macSize:], sig)
// add the hash to the front. Note: this doesn't protect the
// packet in any way.
hash = crypto.Keccak256(packet[macSize:])
copy(packet, hash)
copy(packet, versionPrefix)
copy(packet[versionPrefixSize:], sig)
hash = crypto.Keccak256(packet[versionPrefixSize:])
return packet, hash, nil
}
@ -420,17 +411,16 @@ func decodePacket(buffer []byte, pkt *ingressPacket) error {
}
buf := make([]byte, len(buffer))
copy(buf, buffer)
hash, sig, sigdata := buf[:macSize], buf[macSize:headSize], buf[headSize:]
shouldhash := crypto.Keccak256(buf[macSize:])
if !bytes.Equal(hash, shouldhash) {
return errBadHash
prefix, sig, sigdata := buf[:versionPrefixSize], buf[versionPrefixSize:headSize], buf[headSize:]
if !bytes.Equal(prefix, versionPrefix) {
return errBadPrefix
}
fromID, err := recoverNodeID(crypto.Keccak256(buf[headSize:]), sig)
if err != nil {
return err
}
pkt.rawData = buf
pkt.hash = hash
pkt.hash = crypto.Keccak256(buf[versionPrefixSize:])
pkt.remoteID = fromID
switch pkt.ev = nodeEvent(sigdata[0]); pkt.ev {
case pingPacket:

View File

@ -78,9 +78,6 @@ type Config struct {
// protocol should be started or not.
DiscoveryV5 bool `toml:",omitempty"`
// Listener address for the V5 discovery protocol UDP traffic.
DiscoveryV5Addr string `toml:",omitempty"`
// Name sets the node name of this server.
// Use common.MakeName to create a name that follows existing conventions.
Name string `toml:"-"`
@ -354,6 +351,32 @@ func (srv *Server) Stop() {
srv.loopWG.Wait()
}
// sharedUDPConn implements a shared connection. Write sends messages to the underlying connection while read returns
// messages that were found unprocessable and sent to the unhandled channel by the primary listener.
type sharedUDPConn struct {
*net.UDPConn
unhandled chan discover.ReadPacket
}
// ReadFromUDP implements discv5.conn
func (s *sharedUDPConn) ReadFromUDP(b []byte) (n int, addr *net.UDPAddr, err error) {
packet, ok := <-s.unhandled
if !ok {
return 0, nil, fmt.Errorf("Connection was closed")
}
l := len(packet.Data)
if l > len(b) {
l = len(b)
}
copy(b[:l], packet.Data[:l])
return l, packet.Addr, nil
}
// Close implements discv5.conn
func (s *sharedUDPConn) Close() error {
return nil
}
// Start starts running the server.
// Servers can not be re-used after stopping.
func (srv *Server) Start() (err error) {
@ -388,9 +411,43 @@ func (srv *Server) Start() (err error) {
srv.peerOp = make(chan peerOpFunc)
srv.peerOpDone = make(chan struct{})
var (
conn *net.UDPConn
sconn *sharedUDPConn
realaddr *net.UDPAddr
unhandled chan discover.ReadPacket
)
if !srv.NoDiscovery || srv.DiscoveryV5 {
addr, err := net.ResolveUDPAddr("udp", srv.ListenAddr)
if err != nil {
return err
}
conn, err = net.ListenUDP("udp", addr)
if err != nil {
return err
}
realaddr = conn.LocalAddr().(*net.UDPAddr)
if srv.NAT != nil {
if !realaddr.IP.IsLoopback() {
go nat.Map(srv.NAT, srv.quit, "udp", realaddr.Port, realaddr.Port, "ethereum discovery")
}
// TODO: react to external IP changes over time.
if ext, err := srv.NAT.ExternalIP(); err == nil {
realaddr = &net.UDPAddr{IP: ext, Port: realaddr.Port}
}
}
}
if !srv.NoDiscovery && srv.DiscoveryV5 {
unhandled = make(chan discover.ReadPacket, 100)
sconn = &sharedUDPConn{conn, unhandled}
}
// node table
if !srv.NoDiscovery {
ntab, err := discover.ListenUDP(srv.PrivateKey, srv.ListenAddr, srv.NAT, srv.NodeDatabase, srv.NetRestrict)
ntab, err := discover.ListenUDP(srv.PrivateKey, conn, realaddr, unhandled, srv.NodeDatabase, srv.NetRestrict)
if err != nil {
return err
}
@ -401,7 +458,15 @@ func (srv *Server) Start() (err error) {
}
if srv.DiscoveryV5 {
ntab, err := discv5.ListenUDP(srv.PrivateKey, srv.DiscoveryV5Addr, srv.NAT, "", srv.NetRestrict) //srv.NodeDatabase)
var (
ntab *discv5.Network
err error
)
if sconn != nil {
ntab, err = discv5.ListenUDP(srv.PrivateKey, sconn, realaddr, "", srv.NetRestrict) //srv.NodeDatabase)
} else {
ntab, err = discv5.ListenUDP(srv.PrivateKey, conn, realaddr, "", srv.NetRestrict) //srv.NodeDatabase)
}
if err != nil {
return err
}

View File

@ -56,7 +56,7 @@ var RinkebyV5Bootnodes = []string{
// DiscoveryV5Bootnodes are the enode URLs of the P2P bootstrap nodes for the
// experimental RLPx v5 topic-discovery network.
var DiscoveryV5Bootnodes = []string{
"enode://0cc5f5ffb5d9098c8b8c62325f3797f56509bff942704687b6530992ac706e2cb946b90a34f1f19548cd3c7baccbcaea354531e5983c7d1bc0dee16ce4b6440b@40.118.3.223:30305",
"enode://1c7a64d76c0334b0418c004af2f67c50e36a3be60b5e4790bdac0439d21603469a85fad36f2473c9a80eb043ae60936df905fa28f1ff614c3e5dc34f15dcd2dc@40.118.3.223:30308",
"enode://85c85d7143ae8bb96924f2b54f1b3e70d8c4d367af305325d30a61385a432f247d2c75c45c6b4a60335060d072d7f5b35dd1d4c45f76941f62a4f83b6e75daaf@40.118.3.223:30309",
"enode://0cc5f5ffb5d9098c8b8c62325f3797f56509bff942704687b6530992ac706e2cb946b90a34f1f19548cd3c7baccbcaea354531e5983c7d1bc0dee16ce4b6440b@40.118.3.223:30304",
"enode://1c7a64d76c0334b0418c004af2f67c50e36a3be60b5e4790bdac0439d21603469a85fad36f2473c9a80eb043ae60936df905fa28f1ff614c3e5dc34f15dcd2dc@40.118.3.223:30306",
"enode://85c85d7143ae8bb96924f2b54f1b3e70d8c4d367af305325d30a61385a432f247d2c75c45c6b4a60335060d072d7f5b35dd1d4c45f76941f62a4f83b6e75daaf@40.118.3.223:30307",
}