Merge pull request #19513 from fjl/p2p-discover-split-v4

p2p/discover: split out discv4 code

internal/testlog/testlog.go

@@ -0,0 +1,46 @@
+// Copyright 2017 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 testlog provides a log handler for unit tests.
+package testlog
+
+import (
+	"testing"
+
+	"github.com/ethereum/go-ethereum/log"
+)
+
+// Logger returns a logger which logs to the unit test log of t.
+func Logger(t *testing.T, level log.Lvl) log.Logger {
+	l := log.New()
+	l.SetHandler(Handler(t, level))
+	return l
+}
+
+// Handler returns a log handler which logs to the unit test log of t.
+func Handler(t *testing.T, level log.Lvl) log.Handler {
+	return log.LvlFilterHandler(level, &handler{t, log.TerminalFormat(false)})
+}
+
+type handler struct {
+	t   *testing.T
+	fmt log.Format
+}
+
+func (h *handler) Log(r *log.Record) error {
+	h.t.Logf("%s", h.fmt.Format(r))
+	return nil
+}

p2p/discover/common.go

@@ -0,0 +1,57 @@
+// Copyright 2019 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 discover
+
+import (
+	"crypto/ecdsa"
+	"net"
+
+	"github.com/ethereum/go-ethereum/log"
+	"github.com/ethereum/go-ethereum/p2p/enode"
+	"github.com/ethereum/go-ethereum/p2p/netutil"
+)
+
+type UDPConn interface {
+	ReadFromUDP(b []byte) (n int, addr *net.UDPAddr, err error)
+	WriteToUDP(b []byte, addr *net.UDPAddr) (n int, err error)
+	Close() error
+	LocalAddr() net.Addr
+}
+
+// Config holds Table-related settings.
+type Config struct {
+	// These settings are required and configure the UDP listener:
+	PrivateKey *ecdsa.PrivateKey
+
+	// These settings are optional:
+	NetRestrict *netutil.Netlist  // network whitelist
+	Bootnodes   []*enode.Node     // list of bootstrap nodes
+	Unhandled   chan<- ReadPacket // unhandled packets are sent on this channel
+	Log         log.Logger        // if set, log messages go here
+}
+
+// ListenUDP starts listening for discovery packets on the given UDP socket.
+func ListenUDP(c UDPConn, ln *enode.LocalNode, cfg Config) (*UDPv4, error) {
+	return ListenV4(c, ln, cfg)
+}
+
+// ReadPacket is a packet that couldn't be handled. Those packets are sent to the unhandled
+// channel if configured.
+type ReadPacket struct {
+	Data []byte
+	Addr *net.UDPAddr
+}

p2p/discover/table.go

@@ -23,7 +23,6 @@
 package discover
 
 import (
-	"crypto/ecdsa"
 	crand "crypto/rand"
 	"encoding/binary"
 	"fmt"
@@ -34,7 +33,6 @@ import (
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/p2p/netutil"
@@ -71,26 +69,23 @@ type Table struct {
 	rand    *mrand.Rand       // source of randomness, periodically reseeded
 	ips     netutil.DistinctNetSet
 
+	log        log.Logger
 	db         *enode.DB // database of known nodes
 	net        transport
 	refreshReq chan chan struct{}
 	initDone   chan struct{}
-
-	closeOnce sync.Once
-	closeReq  chan struct{}
-	closed    chan struct{}
+	closeReq   chan struct{}
+	closed     chan struct{}
 
 	nodeAddedHook func(*node) // for testing
 }
 
-// transport is implemented by the UDP transport.
-// it is an interface so we can test without opening lots of UDP
-// sockets and without generating a private key.
+// transport is implemented by UDP transports.
 type transport interface {
-	self() *enode.Node
-	ping(enode.ID, *net.UDPAddr) error
-	findnode(toid enode.ID, addr *net.UDPAddr, target encPubkey) ([]*node, error)
-	close()
+	Self() *enode.Node
+	lookupRandom() []*enode.Node
+	lookupSelf() []*enode.Node
+	ping(*enode.Node) error
 }
 
 // bucket contains nodes, ordered by their last activity. the entry
@@ -101,7 +96,7 @@ type bucket struct {
 	ips          netutil.DistinctNetSet
 }
 
-func newTable(t transport, db *enode.DB, bootnodes []*enode.Node) (*Table, error) {
+func newTable(t transport, db *enode.DB, bootnodes []*enode.Node, log log.Logger) (*Table, error) {
 	tab := &Table{
 		net:        t,
 		db:         db,
@@ -111,6 +106,7 @@ func newTable(t transport, db *enode.DB, bootnodes []*enode.Node) (*Table, error
 		closed:     make(chan struct{}),
 		rand:       mrand.New(mrand.NewSource(0)),
 		ips:        netutil.DistinctNetSet{Subnet: tableSubnet, Limit: tableIPLimit},
+		log:        log,
 	}
 	if err := tab.setFallbackNodes(bootnodes); err != nil {
 		return nil, err
@@ -128,7 +124,7 @@ func newTable(t transport, db *enode.DB, bootnodes []*enode.Node) (*Table, error
 }
 
 func (tab *Table) self() *enode.Node {
-	return tab.net.self()
+	return tab.net.Self()
 }
 
 func (tab *Table) seedRand() {
@@ -180,16 +176,22 @@ func (tab *Table) ReadRandomNodes(buf []*enode.Node) (n int) {
 	return i + 1
 }
 
-// Close terminates the network listener and flushes the node database.
-func (tab *Table) Close() {
-	tab.closeOnce.Do(func() {
-		if tab.net != nil {
-			tab.net.close()
-		}
-		// Wait for loop to end.
-		close(tab.closeReq)
-		<-tab.closed
-	})
+// Resolve searches for a specific node with the given ID.
+// It returns nil if the node could not be found.
+func (tab *Table) Resolve(n *enode.Node) *enode.Node {
+	tab.mutex.Lock()
+	cl := tab.closest(n.ID(), 1, false)
+	tab.mutex.Unlock()
+	if len(cl.entries) > 0 && cl.entries[0].ID() == n.ID() {
+		return unwrapNode(cl.entries[0])
+	}
+	return nil
+}
+
+// close terminates the network listener and flushes the node database.
+func (tab *Table) close() {
+	close(tab.closeReq)
+	<-tab.closed
 }
 
 // setFallbackNodes sets the initial points of contact. These nodes
@@ -215,124 +217,6 @@ func (tab *Table) isInitDone() bool {
 	}
 }
 
-// Resolve searches for a specific node with the given ID.
-// It returns nil if the node could not be found.
-func (tab *Table) Resolve(n *enode.Node) *enode.Node {
-	// If the node is present in the local table, no
-	// network interaction is required.
-	hash := n.ID()
-	tab.mutex.Lock()
-	cl := tab.closest(hash, 1)
-	tab.mutex.Unlock()
-	if len(cl.entries) > 0 && cl.entries[0].ID() == hash {
-		return unwrapNode(cl.entries[0])
-	}
-	// Otherwise, do a network lookup.
-	result := tab.lookup(encodePubkey(n.Pubkey()), true)
-	for _, n := range result {
-		if n.ID() == hash {
-			return unwrapNode(n)
-		}
-	}
-	return nil
-}
-
-// LookupRandom finds random nodes in the network.
-func (tab *Table) LookupRandom() []*enode.Node {
-	var target encPubkey
-	crand.Read(target[:])
-	return unwrapNodes(tab.lookup(target, true))
-}
-
-// lookup performs a network search for nodes close to the given target. It approaches the
-// target by querying nodes that are closer to it on each iteration. The given target does
-// not need to be an actual node identifier.
-func (tab *Table) lookup(targetKey encPubkey, refreshIfEmpty bool) []*node {
-	var (
-		target         = enode.ID(crypto.Keccak256Hash(targetKey[:]))
-		asked          = make(map[enode.ID]bool)
-		seen           = make(map[enode.ID]bool)
-		reply          = make(chan []*node, alpha)
-		pendingQueries = 0
-		result         *nodesByDistance
-	)
-	// don't query further if we hit ourself.
-	// unlikely to happen often in practice.
-	asked[tab.self().ID()] = true
-
-	for {
-		tab.mutex.Lock()
-		// generate initial result set
-		result = tab.closest(target, bucketSize)
-		tab.mutex.Unlock()
-		if len(result.entries) > 0 || !refreshIfEmpty {
-			break
-		}
-		// The result set is empty, all nodes were dropped, refresh.
-		// We actually wait for the refresh to complete here. The very
-		// first query will hit this case and run the bootstrapping
-		// logic.
-		<-tab.refresh()
-		refreshIfEmpty = false
-	}
-
-	for {
-		// ask the alpha closest nodes that we haven't asked yet
-		for i := 0; i < len(result.entries) && pendingQueries < alpha; i++ {
-			n := result.entries[i]
-			if !asked[n.ID()] {
-				asked[n.ID()] = true
-				pendingQueries++
-				go tab.findnode(n, targetKey, reply)
-			}
-		}
-		if pendingQueries == 0 {
-			// we have asked all closest nodes, stop the search
-			break
-		}
-		select {
-		case nodes := <-reply:
-			for _, n := range nodes {
-				if n != nil && !seen[n.ID()] {
-					seen[n.ID()] = true
-					result.push(n, bucketSize)
-				}
-			}
-		case <-tab.closeReq:
-			return nil // shutdown, no need to continue.
-		}
-		pendingQueries--
-	}
-	return result.entries
-}
-
-func (tab *Table) findnode(n *node, targetKey encPubkey, reply chan<- []*node) {
-	fails := tab.db.FindFails(n.ID(), n.IP())
-	r, err := tab.net.findnode(n.ID(), n.addr(), targetKey)
-	if err == errClosed {
-		// Avoid recording failures on shutdown.
-		reply <- nil
-		return
-	} else if len(r) == 0 {
-		fails++
-		tab.db.UpdateFindFails(n.ID(), n.IP(), fails)
-		log.Trace("Findnode failed", "id", n.ID(), "failcount", fails, "err", err)
-		if fails >= maxFindnodeFailures {
-			log.Trace("Too many findnode failures, dropping", "id", n.ID(), "failcount", fails)
-			tab.delete(n)
-		}
-	} else if fails > 0 {
-		tab.db.UpdateFindFails(n.ID(), n.IP(), fails-1)
-	}
-
-	// Grab as many nodes as possible. Some of them might not be alive anymore, but we'll
-	// just remove those again during revalidation.
-	for _, n := range r {
-		tab.addSeenNode(n)
-	}
-	reply <- r
-}
-
 func (tab *Table) refresh() <-chan struct{} {
 	done := make(chan struct{})
 	select {
@@ -417,11 +301,7 @@ func (tab *Table) doRefresh(done chan struct{}) {
 	tab.loadSeedNodes()
 
 	// Run self lookup to discover new neighbor nodes.
-	// We can only do this if we have a secp256k1 identity.
-	var key ecdsa.PublicKey
-	if err := tab.self().Load((*enode.Secp256k1)(&key)); err == nil {
-		tab.lookup(encodePubkey(&key), false)
-	}
+	tab.net.lookupSelf()
 
 	// The Kademlia paper specifies that the bucket refresh should
 	// perform a lookup in the least recently used bucket. We cannot
@@ -430,9 +310,7 @@ func (tab *Table) doRefresh(done chan struct{}) {
 	// sha3 preimage that falls into a chosen bucket.
 	// We perform a few lookups with a random target instead.
 	for i := 0; i < 3; i++ {
-		var target encPubkey
-		crand.Read(target[:])
-		tab.lookup(target, false)
+		tab.net.lookupRandom()
 	}
 }
 
@@ -442,7 +320,7 @@ func (tab *Table) loadSeedNodes() {
 	for i := range seeds {
 		seed := seeds[i]
 		age := log.Lazy{Fn: func() interface{} { return time.Since(tab.db.LastPongReceived(seed.ID(), seed.IP())) }}
-		log.Trace("Found seed node in database", "id", seed.ID(), "addr", seed.addr(), "age", age)
+		tab.log.Trace("Found seed node in database", "id", seed.ID(), "addr", seed.addr(), "age", age)
 		tab.addSeenNode(seed)
 	}
 }
@@ -459,7 +337,7 @@ func (tab *Table) doRevalidate(done chan<- struct{}) {
 	}
 
 	// Ping the selected node and wait for a pong.
-	err := tab.net.ping(last.ID(), last.addr())
+	err := tab.net.ping(unwrapNode(last))
 
 	tab.mutex.Lock()
 	defer tab.mutex.Unlock()
@@ -467,16 +345,16 @@ func (tab *Table) doRevalidate(done chan<- struct{}) {
 	if err == nil {
 		// The node responded, move it to the front.
 		last.livenessChecks++
-		log.Debug("Revalidated node", "b", bi, "id", last.ID(), "checks", last.livenessChecks)
+		tab.log.Debug("Revalidated node", "b", bi, "id", last.ID(), "checks", last.livenessChecks)
 		tab.bumpInBucket(b, last)
 		return
 	}
 	// No reply received, pick a replacement or delete the node if there aren't
 	// any replacements.
 	if r := tab.replace(b, last); r != nil {
-		log.Debug("Replaced dead node", "b", bi, "id", last.ID(), "ip", last.IP(), "checks", last.livenessChecks, "r", r.ID(), "rip", r.IP())
+		tab.log.Debug("Replaced dead node", "b", bi, "id", last.ID(), "ip", last.IP(), "checks", last.livenessChecks, "r", r.ID(), "rip", r.IP())
 	} else {
-		log.Debug("Removed dead node", "b", bi, "id", last.ID(), "ip", last.IP(), "checks", last.livenessChecks)
+		tab.log.Debug("Removed dead node", "b", bi, "id", last.ID(), "ip", last.IP(), "checks", last.livenessChecks)
 	}
 }
 
@@ -520,22 +398,27 @@ func (tab *Table) copyLiveNodes() {
 
 // closest returns the n nodes in the table that are closest to the
 // given id. The caller must hold tab.mutex.
-func (tab *Table) closest(target enode.ID, nresults int) *nodesByDistance {
+func (tab *Table) closest(target enode.ID, nresults int, checklive bool) *nodesByDistance {
 	// This is a very wasteful way to find the closest nodes but
 	// obviously correct. I believe that tree-based buckets would make
 	// this easier to implement efficiently.
 	close := &nodesByDistance{target: target}
 	for _, b := range &tab.buckets {
 		for _, n := range b.entries {
-			if n.livenessChecks > 0 {
-				close.push(n, nresults)
+			if checklive && n.livenessChecks == 0 {
+				continue
 			}
+			close.push(n, nresults)
 		}
 	}
 	return close
 }
 
+// len returns the number of nodes in the table.
 func (tab *Table) len() (n int) {
+	tab.mutex.Lock()
+	defer tab.mutex.Unlock()
+
 	for _, b := range &tab.buckets {
 		n += len(b.entries)
 	}
@@ -641,11 +524,11 @@ func (tab *Table) addIP(b *bucket, ip net.IP) bool {
 		return true
 	}
 	if !tab.ips.Add(ip) {
-		log.Debug("IP exceeds table limit", "ip", ip)
+		tab.log.Debug("IP exceeds table limit", "ip", ip)
 		return false
 	}
 	if !b.ips.Add(ip) {
-		log.Debug("IP exceeds bucket limit", "ip", ip)
+		tab.log.Debug("IP exceeds bucket limit", "ip", ip)
 		tab.ips.Remove(ip)
 		return false
 	}
@@ -754,8 +637,7 @@ func deleteNode(list []*node, n *node) []*node {
 	return list
 }
 
-// nodesByDistance is a list of nodes, ordered by
-// distance to target.
+// nodesByDistance is a list of nodes, ordered by distance to target.
 type nodesByDistance struct {
 	entries []*node
 	target  enode.ID

p2p/discover/table_test.go

@@ -52,7 +52,7 @@ func testPingReplace(t *testing.T, newNodeIsResponding, lastInBucketIsResponding
 	transport := newPingRecorder()
 	tab, db := newTestTable(transport)
 	defer db.Close()
-	defer tab.Close()
+	defer tab.close()
 
 	<-tab.initDone
 
@@ -117,7 +117,7 @@ func TestBucket_bumpNoDuplicates(t *testing.T) {
 	prop := func(nodes []*node, bumps []int) (ok bool) {
 		tab, db := newTestTable(newPingRecorder())
 		defer db.Close()
-		defer tab.Close()
+		defer tab.close()
 
 		b := &bucket{entries: make([]*node, len(nodes))}
 		copy(b.entries, nodes)
@@ -144,7 +144,7 @@ func TestTable_IPLimit(t *testing.T) {
 	transport := newPingRecorder()
 	tab, db := newTestTable(transport)
 	defer db.Close()
-	defer tab.Close()
+	defer tab.close()
 
 	for i := 0; i < tableIPLimit+1; i++ {
 		n := nodeAtDistance(tab.self().ID(), i, net.IP{172, 0, 1, byte(i)})
@@ -161,7 +161,7 @@ func TestTable_BucketIPLimit(t *testing.T) {
 	transport := newPingRecorder()
 	tab, db := newTestTable(transport)
 	defer db.Close()
-	defer tab.Close()
+	defer tab.close()
 
 	d := 3
 	for i := 0; i < bucketIPLimit+1; i++ {
@@ -198,11 +198,11 @@ func TestTable_closest(t *testing.T) {
 		transport := newPingRecorder()
 		tab, db := newTestTable(transport)
 		defer db.Close()
-		defer tab.Close()
+		defer tab.close()
 		fillTable(tab, test.All)
 
 		// check that closest(Target, N) returns nodes
-		result := tab.closest(test.Target, test.N).entries
+		result := tab.closest(test.Target, test.N, false).entries
 		if hasDuplicates(result) {
 			t.Errorf("result contains duplicates")
 			return false
@@ -259,7 +259,7 @@ func TestTable_ReadRandomNodesGetAll(t *testing.T) {
 		transport := newPingRecorder()
 		tab, db := newTestTable(transport)
 		defer db.Close()
-		defer tab.Close()
+		defer tab.close()
 		<-tab.initDone
 
 		for i := 0; i < len(buf); i++ {
@@ -309,7 +309,7 @@ func TestTable_addVerifiedNode(t *testing.T) {
 	tab, db := newTestTable(newPingRecorder())
 	<-tab.initDone
 	defer db.Close()
-	defer tab.Close()
+	defer tab.close()
 
 	// Insert two nodes.
 	n1 := nodeAtDistance(tab.self().ID(), 256, net.IP{88, 77, 66, 1})
@@ -341,7 +341,7 @@ func TestTable_addSeenNode(t *testing.T) {
 	tab, db := newTestTable(newPingRecorder())
 	<-tab.initDone
 	defer db.Close()
-	defer tab.Close()
+	defer tab.close()
 
 	// Insert two nodes.
 	n1 := nodeAtDistance(tab.self().ID(), 256, net.IP{88, 77, 66, 1})
@@ -368,298 +368,6 @@ func TestTable_addSeenNode(t *testing.T) {
 	checkIPLimitInvariant(t, tab)
 }
 
-func TestTable_Lookup(t *testing.T) {
-	tab, db := newTestTable(lookupTestnet)
-	defer db.Close()
-	defer tab.Close()
-
-	// lookup on empty table returns no nodes
-	if results := tab.lookup(lookupTestnet.target, false); len(results) > 0 {
-		t.Fatalf("lookup on empty table returned %d results: %#v", len(results), results)
-	}
-	// seed table with initial node (otherwise lookup will terminate immediately)
-	seedKey, _ := decodePubkey(lookupTestnet.dists[256][0])
-	seed := wrapNode(enode.NewV4(seedKey, net.IP{127, 0, 0, 1}, 0, 256))
-	seed.livenessChecks = 1
-	fillTable(tab, []*node{seed})
-
-	results := tab.lookup(lookupTestnet.target, true)
-	t.Logf("results:")
-	for _, e := range results {
-		t.Logf("  ld=%d, %x", enode.LogDist(lookupTestnet.targetSha, e.ID()), e.ID().Bytes())
-	}
-	if len(results) != bucketSize {
-		t.Errorf("wrong number of results: got %d, want %d", len(results), bucketSize)
-	}
-	if hasDuplicates(results) {
-		t.Errorf("result set contains duplicate entries")
-	}
-	if !sortedByDistanceTo(lookupTestnet.targetSha, results) {
-		t.Errorf("result set not sorted by distance to target")
-	}
-	// TODO: check result nodes are actually closest
-}
-
-// This is the test network for the Lookup test.
-// The nodes were obtained by running testnet.mine with a random NodeID as target.
-var lookupTestnet = &preminedTestnet{
-	target:    hexEncPubkey("166aea4f556532c6d34e8b740e5d314af7e9ac0ca79833bd751d6b665f12dfd38ec563c363b32f02aef4a80b44fd3def94612d497b99cb5f17fd24de454927ec"),
-	targetSha: enode.HexID("5c944ee51c5ae9f72a95eccb8aed0374eecb5119d720cbea6813e8e0d6ad9261"),
-	dists: [257][]encPubkey{
-		240: {
-			hexEncPubkey("2001ad5e3e80c71b952161bc0186731cf5ffe942d24a79230a0555802296238e57ea7a32f5b6f18564eadc1c65389448481f8c9338df0a3dbd18f708cbc2cbcb"),
-			hexEncPubkey("6ba3f4f57d084b6bf94cc4555b8c657e4a8ac7b7baf23c6874efc21dd1e4f56b7eb2721e07f5242d2f1d8381fc8cae535e860197c69236798ba1ad231b105794"),
-		},
-		244: {
-			hexEncPubkey("696ba1f0a9d55c59246f776600542a9e6432490f0cd78f8bb55a196918df2081a9b521c3c3ba48e465a75c10768807717f8f689b0b4adce00e1c75737552a178"),
-		},
-		246: {
-			hexEncPubkey("d6d32178bdc38416f46ffb8b3ec9e4cb2cfff8d04dd7e4311a70e403cb62b10be1b447311b60b4f9ee221a8131fc2cbd45b96dd80deba68a949d467241facfa8"),
-			hexEncPubkey("3ea3d04a43a3dfb5ac11cffc2319248cf41b6279659393c2f55b8a0a5fc9d12581a9d97ef5d8ff9b5abf3321a290e8f63a4f785f450dc8a672aba3ba2ff4fdab"),
-			hexEncPubkey("2fc897f05ae585553e5c014effd3078f84f37f9333afacffb109f00ca8e7a3373de810a3946be971cbccdfd40249f9fe7f322118ea459ac71acca85a1ef8b7f4"),
-		},
-		247: {
-			hexEncPubkey("3155e1427f85f10a5c9a7755877748041af1bcd8d474ec065eb33df57a97babf54bfd2103575fa829115d224c523596b401065a97f74010610fce76382c0bf32"),
-			hexEncPubkey("312c55512422cf9b8a4097e9a6ad79402e87a15ae909a4bfefa22398f03d20951933beea1e4dfa6f968212385e829f04c2d314fc2d4e255e0d3bc08792b069db"),
-			hexEncPubkey("38643200b172dcfef857492156971f0e6aa2c538d8b74010f8e140811d53b98c765dd2d96126051913f44582e8c199ad7c6d6819e9a56483f637feaac9448aac"),
-			hexEncPubkey("8dcab8618c3253b558d459da53bd8fa68935a719aff8b811197101a4b2b47dd2d47295286fc00cc081bb542d760717d1bdd6bec2c37cd72eca367d6dd3b9df73"),
-			hexEncPubkey("8b58c6073dd98bbad4e310b97186c8f822d3a5c7d57af40e2136e88e315afd115edb27d2d0685a908cfe5aa49d0debdda6e6e63972691d6bd8c5af2d771dd2a9"),
-			hexEncPubkey("2cbb718b7dc682da19652e7d9eb4fefaf7b7147d82c1c2b6805edf77b85e29fde9f6da195741467ff2638dc62c8d3e014ea5686693c15ed0080b6de90354c137"),
-			hexEncPubkey("e84027696d3f12f2de30a9311afea8fbd313c2360daff52bb5fc8c7094d5295758bec3134e4eef24e4cdf377b40da344993284628a7a346eba94f74160998feb"),
-			hexEncPubkey("f1357a4f04f9d33753a57c0b65ba20a5d8777abbffd04e906014491c9103fb08590e45548d37aa4bd70965e2e81ddba94f31860348df01469eec8c1829200a68"),
-			hexEncPubkey("4ab0a75941b12892369b4490a1928c8ca52a9ad6d3dffbd1d8c0b907bc200fe74c022d011ec39b64808a39c0ca41f1d3254386c3e7733e7044c44259486461b6"),
-			hexEncPubkey("d45150a72dc74388773e68e03133a3b5f51447fe91837d566706b3c035ee4b56f160c878c6273394daee7f56cc398985269052f22f75a8057df2fe6172765354"),
-		},
-		248: {
-			hexEncPubkey("6aadfce366a189bab08ac84721567483202c86590642ea6d6a14f37ca78d82bdb6509eb7b8b2f6f63c78ae3ae1d8837c89509e41497d719b23ad53dd81574afa"),
-			hexEncPubkey("a605ecfd6069a4cf4cf7f5840e5bc0ce10d23a3ac59e2aaa70c6afd5637359d2519b4524f56fc2ca180cdbebe54262f720ccaae8c1b28fd553c485675831624d"),
-			hexEncPubkey("29701451cb9448ca33fc33680b44b840d815be90146eb521641efbffed0859c154e8892d3906eae9934bfacee72cd1d2fa9dd050fd18888eea49da155ab0efd2"),
-			hexEncPubkey("3ed426322dee7572b08592e1e079f8b6c6b30e10e6243edd144a6a48fdbdb83df73a6e41b1143722cb82604f2203a32758610b5d9544f44a1a7921ba001528c1"),
-			hexEncPubkey("b2e2a2b7fdd363572a3256e75435fab1da3b16f7891a8bd2015f30995dae665d7eabfd194d87d99d5df628b4bbc7b04e5b492c596422dd8272746c7a1b0b8e4f"),
-			hexEncPubkey("0c69c9756162c593e85615b814ce57a2a8ca2df6c690b9c4e4602731b61e1531a3bbe3f7114271554427ffabea80ad8f36fa95a49fa77b675ae182c6ccac1728"),
-			hexEncPubkey("8d28be21d5a97b0876442fa4f5e5387f5bf3faad0b6f13b8607b64d6e448c0991ca28dd7fe2f64eb8eadd7150bff5d5666aa6ed868b84c71311f4ba9a38569dd"),
-			hexEncPubkey("2c677e1c64b9c9df6359348a7f5f33dc79e22f0177042486d125f8b6ca7f0dc756b1f672aceee5f1746bcff80aaf6f92a8dc0c9fbeb259b3fa0da060de5ab7e8"),
-			hexEncPubkey("3994880f94a8678f0cd247a43f474a8af375d2a072128da1ad6cae84a244105ff85e94fc7d8496f639468de7ee998908a91c7e33ef7585fff92e984b210941a1"),
-			hexEncPubkey("b45a9153c08d002a48090d15d61a7c7dad8c2af85d4ff5bd36ce23a9a11e0709bf8d56614c7b193bc028c16cbf7f20dfbcc751328b64a924995d47b41e452422"),
-			hexEncPubkey("057ab3a9e53c7a84b0f3fc586117a525cdd18e313f52a67bf31798d48078e325abe5cfee3f6c2533230cb37d0549289d692a29dd400e899b8552d4b928f6f907"),
-			hexEncPubkey("0ddf663d308791eb92e6bd88a2f8cb45e4f4f35bb16708a0e6ff7f1362aa6a73fedd0a1b1557fb3365e38e1b79d6918e2fae2788728b70c9ab6b51a3b94a4338"),
-			hexEncPubkey("f637e07ff50cc1e3731735841c4798411059f2023abcf3885674f3e8032531b0edca50fd715df6feb489b6177c345374d64f4b07d257a7745de393a107b013a5"),
-			hexEncPubkey("e24ec7c6eec094f63c7b3239f56d311ec5a3e45bc4e622a1095a65b95eea6fe13e29f3b6b7a2cbfe40906e3989f17ac834c3102dd0cadaaa26e16ee06d782b72"),
-			hexEncPubkey("b76ea1a6fd6506ef6e3506a4f1f60ed6287fff8114af6141b2ff13e61242331b54082b023cfea5b3083354a4fb3f9eb8be01fb4a518f579e731a5d0707291a6b"),
-			hexEncPubkey("9b53a37950ca8890ee349b325032d7b672cab7eced178d3060137b24ef6b92a43977922d5bdfb4a3409a2d80128e02f795f9dae6d7d99973ad0e23a2afb8442f"),
-		},
-		249: {
-			hexEncPubkey("675ae65567c3c72c50c73bc0fd4f61f202ea5f93346ca57b551de3411ccc614fad61cb9035493af47615311b9d44ee7a161972ee4d77c28fe1ec029d01434e6a"),
-			hexEncPubkey("8eb81408389da88536ae5800392b16ef5109d7ea132c18e9a82928047ecdb502693f6e4a4cdd18b54296caf561db937185731456c456c98bfe7de0baf0eaa495"),
-			hexEncPubkey("2adba8b1612a541771cb93a726a38a4b88e97b18eced2593eb7daf82f05a5321ca94a72cc780c306ff21e551a932fc2c6d791e4681907b5ceab7f084c3fa2944"),
-			hexEncPubkey("b1b4bfbda514d9b8f35b1c28961da5d5216fe50548f4066f69af3b7666a3b2e06eac646735e963e5c8f8138a2fb95af15b13b23ff00c6986eccc0efaa8ee6fb4"),
-			hexEncPubkey("d2139281b289ad0e4d7b4243c4364f5c51aac8b60f4806135de06b12b5b369c9e43a6eb494eab860d115c15c6fbb8c5a1b0e382972e0e460af395b8385363de7"),
-			hexEncPubkey("4a693df4b8fc5bdc7cec342c3ed2e228d7c5b4ab7321ddaa6cccbeb45b05a9f1d95766b4002e6d4791c2deacb8a667aadea6a700da28a3eea810a30395701bbc"),
-			hexEncPubkey("ab41611195ec3c62bb8cd762ee19fb182d194fd141f4a66780efbef4b07ce916246c022b841237a3a6b512a93431157edd221e854ed2a259b72e9c5351f44d0c"),
-			hexEncPubkey("68e8e26099030d10c3c703ae7045c0a48061fb88058d853b3e67880014c449d4311014da99d617d3150a20f1a3da5e34bf0f14f1c51fe4dd9d58afd222823176"),
-			hexEncPubkey("3fbcacf546fb129cd70fc48de3b593ba99d3c473798bc309292aca280320e0eacc04442c914cad5c4cf6950345ba79b0d51302df88285d4e83ee3fe41339eee7"),
-			hexEncPubkey("1d4a623659f7c8f80b6c3939596afdf42e78f892f682c768ad36eb7bfba402dbf97aea3a268f3badd8fe7636be216edf3d67ee1e08789ebbc7be625056bd7109"),
-			hexEncPubkey("a283c474ab09da02bbc96b16317241d0627646fcc427d1fe790b76a7bf1989ced90f92101a973047ae9940c92720dffbac8eff21df8cae468a50f72f9e159417"),
-			hexEncPubkey("dbf7e5ad7f87c3dfecae65d87c3039e14ed0bdc56caf00ce81931073e2e16719d746295512ff7937a15c3b03603e7c41a4f9df94fcd37bb200dd8f332767e9cb"),
-			hexEncPubkey("caaa070a26692f64fc77f30d7b5ae980d419b4393a0f442b1c821ef58c0862898b0d22f74a4f8c5d83069493e3ec0b92f17dc1fe6e4cd437c1ec25039e7ce839"),
-			hexEncPubkey("874cc8d1213beb65c4e0e1de38ef5d8165235893ac74ab5ea937c885eaab25c8d79dad0456e9fd3e9450626cac7e107b004478fb59842f067857f39a47cee695"),
-			hexEncPubkey("d94193f236105010972f5df1b7818b55846592a0445b9cdc4eaed811b8c4c0f7c27dc8cc9837a4774656d6b34682d6d329d42b6ebb55da1d475c2474dc3dfdf4"),
-			hexEncPubkey("edd9af6aded4094e9785637c28fccbd3980cbe28e2eb9a411048a23c2ace4bd6b0b7088a7817997b49a3dd05fc6929ca6c7abbb69438dbdabe65e971d2a794b2"),
-		},
-		250: {
-			hexEncPubkey("53a5bd1215d4ab709ae8fdc2ced50bba320bced78bd9c5dc92947fb402250c914891786db0978c898c058493f86fc68b1c5de8a5cb36336150ac7a88655b6c39"),
-			hexEncPubkey("b7f79e3ab59f79262623c9ccefc8f01d682323aee56ffbe295437487e9d5acaf556a9c92e1f1c6a9601f2b9eb6b027ae1aeaebac71d61b9b78e88676efd3e1a3"),
-			hexEncPubkey("d374bf7e8d7ffff69cc00bebff38ef5bc1dcb0a8d51c1a3d70e61ac6b2e2d6617109254b0ac224354dfbf79009fe4239e09020c483cc60c071e00b9238684f30"),
-			hexEncPubkey("1e1eac1c9add703eb252eb991594f8f5a173255d526a855fab24ae57dc277e055bc3c7a7ae0b45d437c4f47a72d97eb7b126f2ba344ba6c0e14b2c6f27d4b1e6"),
-			hexEncPubkey("ae28953f63d4bc4e706712a59319c111f5ff8f312584f65d7436b4cd3d14b217b958f8486bad666b4481fe879019fb1f767cf15b3e3e2711efc33b56d460448a"),
-			hexEncPubkey("934bb1edf9c7a318b82306aca67feb3d6b434421fa275d694f0b4927afd8b1d3935b727fd4ff6e3d012e0c82f1824385174e8c6450ade59c2a43281a4b3446b6"),
-			hexEncPubkey("9eef3f28f70ce19637519a0916555bf76d26de31312ac656cf9d3e379899ea44e4dd7ffcce923b4f3563f8a00489a34bd6936db0cbb4c959d32c49f017e07d05"),
-			hexEncPubkey("82200872e8f871c48f1fad13daec6478298099b591bb3dbc4ef6890aa28ebee5860d07d70be62f4c0af85085a90ae8179ee8f937cf37915c67ea73e704b03ee7"),
-			hexEncPubkey("6c75a5834a08476b7fc37ff3dc2011dc3ea3b36524bad7a6d319b18878fad813c0ba76d1f4555cacd3890c865438c21f0e0aed1f80e0a157e642124c69f43a11"),
-			hexEncPubkey("995b873742206cb02b736e73a88580c2aacb0bd4a3c97a647b647bcab3f5e03c0e0736520a8b3600da09edf4248991fb01091ec7ff3ec7cdc8a1beae011e7aae"),
-			hexEncPubkey("c773a056594b5cdef2e850d30891ff0e927c3b1b9c35cd8e8d53a1017001e237468e1ece3ae33d612ca3e6abb0a9169aa352e9dcda358e5af2ad982b577447db"),
-			hexEncPubkey("2b46a5f6923f475c6be99ec6d134437a6d11f6bb4b4ac6bcd94572fa1092639d1c08aeefcb51f0912f0a060f71d4f38ee4da70ecc16010b05dd4a674aab14c3a"),
-			hexEncPubkey("af6ab501366debbaa0d22e20e9688f32ef6b3b644440580fd78de4fe0e99e2a16eb5636bbae0d1c259df8ddda77b35b9a35cbc36137473e9c68fbc9d203ba842"),
-			hexEncPubkey("c9f6f2dd1a941926f03f770695bda289859e85fabaf94baaae20b93e5015dc014ba41150176a36a1884adb52f405194693e63b0c464a6891cc9cc1c80d450326"),
-			hexEncPubkey("5b116f0751526868a909b61a30b0c5282c37df6925cc03ddea556ef0d0602a9595fd6c14d371f8ed7d45d89918a032dcd22be4342a8793d88fdbeb3ca3d75bd7"),
-			hexEncPubkey("50f3222fb6b82481c7c813b2172e1daea43e2710a443b9c2a57a12bd160dd37e20f87aa968c82ad639af6972185609d47036c0d93b4b7269b74ebd7073221c10"),
-		},
-		251: {
-			hexEncPubkey("9b8f702a62d1bee67bedfeb102eca7f37fa1713e310f0d6651cc0c33ea7c5477575289ccd463e5a2574a00a676a1fdce05658ba447bb9d2827f0ba47b947e894"),
-			hexEncPubkey("b97532eb83054ed054b4abdf413bb30c00e4205545c93521554dbe77faa3cfaa5bd31ef466a107b0b34a71ec97214c0c83919720142cddac93aa7a3e928d4708"),
-			hexEncPubkey("2f7a5e952bfb67f2f90b8441b5fadc9ee13b1dcde3afeeb3dd64bf937f86663cc5c55d1fa83952b5422763c7df1b7f2794b751c6be316ebc0beb4942e65ab8c1"),
-			hexEncPubkey("42c7483781727051a0b3660f14faf39e0d33de5e643702ae933837d036508ab856ce7eec8ec89c4929a4901256e5233a3d847d5d4893f91bcf21835a9a880fee"),
-			hexEncPubkey("873bae27bf1dc854408fba94046a53ab0c965cebe1e4e12290806fc62b88deb1f4a47f9e18f78fc0e7913a0c6e42ac4d0fc3a20cea6bc65f0c8a0ca90b67521e"),
-			hexEncPubkey("a7e3a370bbd761d413f8d209e85886f68bf73d5c3089b2dc6fa42aab1ecb5162635497eed95dee2417f3c9c74a3e76319625c48ead2e963c7de877cd4551f347"),
-			hexEncPubkey("528597534776a40df2addaaea15b6ff832ce36b9748a265768368f657e76d58569d9f30dbb91e91cf0ae7efe8f402f17aa0ae15f5c55051ba03ba830287f4c42"),
-			hexEncPubkey("461d8bd4f13c3c09031fdb84f104ed737a52f630261463ce0bdb5704259bab4b737dda688285b8444dbecaecad7f50f835190b38684ced5e90c54219e5adf1bc"),
-			hexEncPubkey("6ec50c0be3fd232737090fc0111caaf0bb6b18f72be453428087a11a97fd6b52db0344acbf789a689bd4f5f50f79017ea784f8fd6fe723ad6ae675b9e3b13e21"),
-			hexEncPubkey("12fc5e2f77a83fdcc727b79d8ae7fe6a516881138d3011847ee136b400fed7cfba1f53fd7a9730253c7aa4f39abeacd04f138417ba7fcb0f36cccc3514e0dab6"),
-			hexEncPubkey("4fdbe75914ccd0bce02101606a1ccf3657ec963e3b3c20239d5fec87673fe446d649b4f15f1fe1a40e6cfbd446dda2d31d40bb602b1093b8fcd5f139ba0eb46a"),
-			hexEncPubkey("3753668a0f6281e425ea69b52cb2d17ab97afbe6eb84cf5d25425bc5e53009388857640668fadd7c110721e6047c9697803bd8a6487b43bb343bfa32ebf24039"),
-			hexEncPubkey("2e81b16346637dec4410fd88e527346145b9c0a849dbf2628049ac7dae016c8f4305649d5659ec77f1e8a0fac0db457b6080547226f06283598e3740ad94849a"),
-			hexEncPubkey("802c3cc27f91c89213223d758f8d2ecd41135b357b6d698f24d811cdf113033a81c38e0bdff574a5c005b00a8c193dc2531f8c1fa05fa60acf0ab6f2858af09f"),
-			hexEncPubkey("fcc9a2e1ac3667026ff16192876d1813bb75abdbf39b929a92863012fe8b1d890badea7a0de36274d5c1eb1e8f975785532c50d80fd44b1a4b692f437303393f"),
-			hexEncPubkey("6d8b3efb461151dd4f6de809b62726f5b89e9b38e9ba1391967f61cde844f7528fecf821b74049207cee5a527096b31f3ad623928cd3ce51d926fa345a6b2951"),
-		},
-		252: {
-			hexEncPubkey("f1ae93157cc48c2075dd5868fbf523e79e06caf4b8198f352f6e526680b78ff4227263de92612f7d63472bd09367bb92a636fff16fe46ccf41614f7a72495c2a"),
-			hexEncPubkey("587f482d111b239c27c0cb89b51dd5d574db8efd8de14a2e6a1400c54d4567e77c65f89c1da52841212080b91604104768350276b6682f2f961cdaf4039581c7"),
-			hexEncPubkey("e3f88274d35cefdaabdf205afe0e80e936cc982b8e3e47a84ce664c413b29016a4fb4f3a3ebae0a2f79671f8323661ed462bf4390af94c424dc8ace0c301b90f"),
-			hexEncPubkey("0ddc736077da9a12ba410dc5ea63cbcbe7659dd08596485b2bff3435221f82c10d263efd9af938e128464be64a178b7cd22e19f400d5802f4c9df54bf89f2619"),
-			hexEncPubkey("784aa34d833c6ce63fcc1279630113c3272e82c4ae8c126c5a52a88ac461b6baeed4244e607b05dc14e5b2f41c70a273c3804dea237f14f7a1e546f6d1309d14"),
-			hexEncPubkey("f253a2c354ee0e27cfcae786d726753d4ad24be6516b279a936195a487de4a59dbc296accf20463749ff55293263ed8c1b6365eecb248d44e75e9741c0d18205"),
-			hexEncPubkey("a1910b80357b3ad9b4593e0628922939614dc9056a5fbf477279c8b2c1d0b4b31d89a0c09d0d41f795271d14d3360ef08a3f821e65e7e1f56c07a36afe49c7c5"),
-			hexEncPubkey("f1168552c2efe541160f0909b0b4a9d6aeedcf595cdf0e9b165c97e3e197471a1ee6320e93389edfba28af6eaf10de98597ad56e7ab1b504ed762451996c3b98"),
-			hexEncPubkey("b0c8e5d2c8634a7930e1a6fd082e448c6cf9d2d8b7293558b59238815a4df926c286bf297d2049f14e8296a6eb3256af614ec1812c4f2bbe807673b58bf14c8c"),
-			hexEncPubkey("0fb346076396a38badc342df3679b55bd7f40a609ab103411fe45082c01f12ea016729e95914b2b5540e987ff5c9b133e85862648e7f36abdfd23100d248d234"),
-			hexEncPubkey("f736e0cc83417feaa280d9483f5d4d72d1b036cd0c6d9cbdeb8ac35ceb2604780de46dddaa32a378474e1d5ccdf79b373331c30c7911ade2ae32f98832e5de1f"),
-			hexEncPubkey("8b02991457602f42b38b342d3f2259ae4100c354b3843885f7e4e07bd644f64dab94bb7f38a3915f8b7f11d8e3f81c28e07a0078cf79d7397e38a7b7e0c857e2"),
-			hexEncPubkey("9221d9f04a8a184993d12baa91116692bb685f887671302999d69300ad103eb2d2c75a09d8979404c6dd28f12362f58a1a43619c493d9108fd47588a23ce5824"),
-			hexEncPubkey("652797801744dada833fff207d67484742eea6835d695925f3e618d71b68ec3c65bdd85b4302b2cdcb835ad3f94fd00d8da07e570b41bc0d2bcf69a8de1b3284"),
-			hexEncPubkey("d84f06fe64debc4cd0625e36d19b99014b6218375262cc2209202bdbafd7dffcc4e34ce6398e182e02fd8faeed622c3e175545864902dfd3d1ac57647cddf4c6"),
-			hexEncPubkey("d0ed87b294f38f1d741eb601020eeec30ac16331d05880fe27868f1e454446de367d7457b41c79e202eaf9525b029e4f1d7e17d85a55f83a557c005c68d7328a"),
-		},
-		253: {
-			hexEncPubkey("ad4485e386e3cc7c7310366a7c38fb810b8896c0d52e55944bfd320ca294e7912d6c53c0a0cf85e7ce226e92491d60430e86f8f15cda0161ed71893fb4a9e3a1"),
-			hexEncPubkey("36d0e7e5b7734f98c6183eeeb8ac5130a85e910a925311a19c4941b1290f945d4fc3996b12ef4966960b6fa0fb29b1604f83a0f81bd5fd6398d2e1a22e46af0c"),
-			hexEncPubkey("7d307d8acb4a561afa23bdf0bd945d35c90245e26345ec3a1f9f7df354222a7cdcb81339c9ed6744526c27a1a0c8d10857e98df942fa433602facac71ac68a31"),
-			hexEncPubkey("d97bf55f88c83fae36232661af115d66ca600fc4bd6d1fb35ff9bb4dad674c02cf8c8d05f317525b5522250db58bb1ecafb7157392bf5aa61b178c61f098d995"),
-			hexEncPubkey("7045d678f1f9eb7a4613764d17bd5698796494d0bf977b16f2dbc272b8a0f7858a60805c022fc3d1fe4f31c37e63cdaca0416c0d053ef48a815f8b19121605e0"),
-			hexEncPubkey("14e1f21418d445748de2a95cd9a8c3b15b506f86a0acabd8af44bb968ce39885b19c8822af61b3dd58a34d1f265baec30e3ae56149dc7d2aa4a538f7319f69c8"),
-			hexEncPubkey("b9453d78281b66a4eac95a1546017111eaaa5f92a65d0de10b1122940e92b319728a24edf4dec6acc412321b1c95266d39c7b3a5d265c629c3e49a65fb022c09"),
-			hexEncPubkey("e8a49248419e3824a00d86af422f22f7366e2d4922b304b7169937616a01d9d6fa5abf5cc01061a352dc866f48e1fa2240dbb453d872b1d7be62bdfc1d5e248c"),
-			hexEncPubkey("bebcff24b52362f30e0589ee573ce2d86f073d58d18e6852a592fa86ceb1a6c9b96d7fb9ec7ed1ed98a51b6743039e780279f6bb49d0a04327ac7a182d9a56f6"),
-			hexEncPubkey("d0835e5a4291db249b8d2fca9f503049988180c7d247bedaa2cf3a1bad0a76709360a85d4f9a1423b2cbc82bb4d94b47c0cde20afc430224834c49fe312a9ae3"),
-			hexEncPubkey("6b087fe2a2da5e4f0b0f4777598a4a7fb66bf77dbd5bfc44e8a7eaa432ab585a6e226891f56a7d4f5ed11a7c57b90f1661bba1059590ca4267a35801c2802913"),
-			hexEncPubkey("d901e5bde52d1a0f4ddf010a686a53974cdae4ebe5c6551b3c37d6b6d635d38d5b0e5f80bc0186a2c7809dbf3a42870dd09643e68d32db896c6da8ba734579e7"),
-			hexEncPubkey("96419fb80efae4b674402bb969ebaab86c1274f29a83a311e24516d36cdf148fe21754d46c97688cdd7468f24c08b13e4727c29263393638a3b37b99ff60ebca"),
-			hexEncPubkey("7b9c1889ae916a5d5abcdfb0aaedcc9c6f9eb1c1a4f68d0c2d034fe79ac610ce917c3abc670744150fa891bfcd8ab14fed6983fca964de920aa393fa7b326748"),
-			hexEncPubkey("7a369b2b8962cc4c65900be046482fbf7c14f98a135bbbae25152c82ad168fb2097b3d1429197cf46d3ce9fdeb64808f908a489cc6019725db040060fdfe5405"),
-			hexEncPubkey("47bcae48288da5ecc7f5058dfa07cf14d89d06d6e449cb946e237aa6652ea050d9f5a24a65efdc0013ccf232bf88670979eddef249b054f63f38da9d7796dbd8"),
-		},
-		254: {
-			hexEncPubkey("099739d7abc8abd38ecc7a816c521a1168a4dbd359fa7212a5123ab583ffa1cf485a5fed219575d6475dbcdd541638b2d3631a6c7fce7474e7fe3cba1d4d5853"),
-			hexEncPubkey("c2b01603b088a7182d0cf7ef29fb2b04c70acb320fccf78526bf9472e10c74ee70b3fcfa6f4b11d167bd7d3bc4d936b660f2c9bff934793d97cb21750e7c3d31"),
-			hexEncPubkey("20e4d8f45f2f863e94b45548c1ef22a11f7d36f263e4f8623761e05a64c4572379b000a52211751e2561b0f14f4fc92dd4130410c8ccc71eb4f0e95a700d4ca9"),
-			hexEncPubkey("27f4a16cc085e72d86e25c98bd2eca173eaaee7565c78ec5a52e9e12b2211f35de81b5b45e9195de2ebfe29106742c59112b951a04eb7ae48822911fc1f9389e"),
-			hexEncPubkey("55db5ee7d98e7f0b1c3b9d5be6f2bc619a1b86c3cdd513160ad4dcf267037a5fffad527ac15d50aeb32c59c13d1d4c1e567ebbf4de0d25236130c8361f9aac63"),
-			hexEncPubkey("883df308b0130fc928a8559fe50667a0fff80493bc09685d18213b2db241a3ad11310ed86b0ef662b3ce21fc3d9aa7f3fc24b8d9afe17c7407e9afd3345ae548"),
-			hexEncPubkey("c7af968cc9bc8200c3ee1a387405f7563be1dce6710a3439f42ea40657d0eae9d2b3c16c42d779605351fcdece4da637b9804e60ca08cfb89aec32c197beffa6"),
-			hexEncPubkey("3e66f2b788e3ff1d04106b80597915cd7afa06c405a7ae026556b6e583dca8e05cfbab5039bb9a1b5d06083ffe8de5780b1775550e7218f5e98624bf7af9a0a8"),
-			hexEncPubkey("4fc7f53764de3337fdaec0a711d35d3a923e72fa65025444d12230b3552ed43d9b2d1ad08ccb11f2d50c58809e6dd74dde910e195294fca3b47ae5a3967cc479"),
-			hexEncPubkey("bafdfdcf6ccaa989436752fa97c77477b6baa7deb374b16c095492c529eb133e8e2f99e1977012b64767b9d34b2cf6d2048ed489bd822b5139b523f6a423167b"),
-			hexEncPubkey("7f5d78008a4312fe059104ce80202c82b8915c2eb4411c6b812b16f7642e57c00f2c9425121f5cbac4257fe0b3e81ef5dea97ea2dbaa98f6a8b6fd4d1e5980bb"),
-			hexEncPubkey("598c37fe78f922751a052f463aeb0cb0bc7f52b7c2a4cf2da72ec0931c7c32175d4165d0f8998f7320e87324ac3311c03f9382a5385c55f0407b7a66b2acd864"),
-			hexEncPubkey("f758c4136e1c148777a7f3275a76e2db0b2b04066fd738554ec398c1c6cc9fb47e14a3b4c87bd47deaeab3ffd2110514c3855685a374794daff87b605b27ee2e"),
-			hexEncPubkey("0307bb9e4fd865a49dcf1fe4333d1b944547db650ab580af0b33e53c4fef6c789531110fac801bbcbce21fc4d6f61b6d5b24abdf5b22e3030646d579f6dca9c2"),
-			hexEncPubkey("82504b6eb49bb2c0f91a7006ce9cefdbaf6df38706198502c2e06601091fc9dc91e4f15db3410d45c6af355bc270b0f268d3dff560f956985c7332d4b10bd1ed"),
-			hexEncPubkey("b39b5b677b45944ceebe76e76d1f051de2f2a0ec7b0d650da52135743e66a9a5dba45f638258f9a7545d9a790c7fe6d3fdf82c25425c7887323e45d27d06c057"),
-		},
-		255: {
-			hexEncPubkey("5c4d58d46e055dd1f093f81ee60a675e1f02f54da6206720adee4dccef9b67a31efc5c2a2949c31a04ee31beadc79aba10da31440a1f9ff2a24093c63c36d784"),
-			hexEncPubkey("ea72161ffdd4b1e124c7b93b0684805f4c4b58d617ed498b37a145c670dbc2e04976f8785583d9c805ffbf343c31d492d79f841652bbbd01b61ed85640b23495"),
-			hexEncPubkey("51caa1d93352d47a8e531692a3612adac1e8ac68d0a200d086c1c57ae1e1a91aa285ab242e8c52ef9d7afe374c9485b122ae815f1707b875569d0433c1c3ce85"),
-			hexEncPubkey("c08397d5751b47bd3da044b908be0fb0e510d3149574dff7aeab33749b023bb171b5769990fe17469dbebc100bc150e798aeda426a2dcc766699a225fddd75c6"),
-			hexEncPubkey("0222c1c194b749736e593f937fad67ee348ac57287a15c7e42877aa38a9b87732a408bca370f812efd0eedbff13e6d5b854bf3ba1dec431a796ed47f32552b09"),
-			hexEncPubkey("03d859cd46ef02d9bfad5268461a6955426845eef4126de6be0fa4e8d7e0727ba2385b78f1a883a8239e95ebb814f2af8379632c7d5b100688eebc5841209582"),
-			hexEncPubkey("64d5004b7e043c39ff0bd10cb20094c287721d5251715884c280a612b494b3e9e1c64ba6f67614994c7d969a0d0c0295d107d53fc225d47c44c4b82852d6f960"),
-			hexEncPubkey("b0a5eefb2dab6f786670f35bf9641eefe6dd87fd3f1362bcab4aaa792903500ab23d88fae68411372e0813b057535a601d46e454323745a948017f6063a47b1f"),
-			hexEncPubkey("0cc6df0a3433d448b5684d2a3ffa9d1a825388177a18f44ad0008c7bd7702f1ec0fc38b83506f7de689c3b6ecb552599927e29699eed6bb867ff08f80068b287"),
-			hexEncPubkey("50772f7b8c03a4e153355fbbf79c8a80cf32af656ff0c7873c99911099d04a0dae0674706c357e0145ad017a0ade65e6052cb1b0d574fcd6f67da3eee0ace66b"),
-			hexEncPubkey("1ae37829c9ef41f8b508b82259ebac76b1ed900d7a45c08b7970f25d2d48ddd1829e2f11423a18749940b6dab8598c6e416cef0efd47e46e51f29a0bc65b37cd"),
-			hexEncPubkey("ba973cab31c2af091fc1644a93527d62b2394999e2b6ccbf158dd5ab9796a43d408786f1803ef4e29debfeb62fce2b6caa5ab2b24d1549c822a11c40c2856665"),
-			hexEncPubkey("bc413ad270dd6ea25bddba78f3298b03b8ba6f8608ac03d06007d4116fa78ef5a0cfe8c80155089382fc7a193243ee5500082660cb5d7793f60f2d7d18650964"),
-			hexEncPubkey("5a6a9ef07634d9eec3baa87c997b529b92652afa11473dfee41ef7037d5c06e0ddb9fe842364462d79dd31cff8a59a1b8d5bc2b810dea1d4cbbd3beb80ecec83"),
-			hexEncPubkey("f492c6ee2696d5f682f7f537757e52744c2ae560f1090a07024609e903d334e9e174fc01609c5a229ddbcac36c9d21adaf6457dab38a25bfd44f2f0ee4277998"),
-			hexEncPubkey("459e4db99298cb0467a90acee6888b08bb857450deac11015cced5104853be5adce5b69c740968bc7f931495d671a70cad9f48546d7cd203357fe9af0e8d2164"),
-		},
-		256: {
-			hexEncPubkey("a8593af8a4aef7b806b5197612017951bac8845a1917ca9a6a15dd6086d608505144990b245785c4cd2d67a295701c7aac2aa18823fb0033987284b019656268"),
-			hexEncPubkey("d2eebef914928c3aad77fc1b2a495f52d2294acf5edaa7d8a530b540f094b861a68fe8348a46a7c302f08ab609d85912a4968eacfea0740847b29421b4795d9e"),
-			hexEncPubkey("b14bfcb31495f32b650b63cf7d08492e3e29071fdc73cf2da0da48d4b191a70ba1a65f42ad8c343206101f00f8a48e8db4b08bf3f622c0853e7323b250835b91"),
-			hexEncPubkey("7feaee0d818c03eb30e4e0bf03ade0f3c21ca38e938a761aa1781cf70bda8cc5cd631a6cc53dd44f1d4a6d3e2dae6513c6c66ee50cb2f0e9ad6f7e319b309fd9"),
-			hexEncPubkey("4ca3b657b139311db8d583c25dd5963005e46689e1317620496cc64129c7f3e52870820e0ec7941d28809311df6db8a2867bbd4f235b4248af24d7a9c22d1232"),
-			hexEncPubkey("1181defb1d16851d42dd951d84424d6bd1479137f587fa184d5a8152be6b6b16ed08bcdb2c2ed8539bcde98c80c432875f9f724737c316a2bd385a39d3cab1d8"),
-			hexEncPubkey("d9dd818769fa0c3ec9f553c759b92476f082817252a04a47dc1777740b1731d280058c66f982812f173a294acf4944a85ba08346e2de153ba3ba41ce8a62cb64"),
-			hexEncPubkey("bd7c4f8a9e770aa915c771b15e107ca123d838762da0d3ffc53aa6b53e9cd076cffc534ec4d2e4c334c683f1f5ea72e0e123f6c261915ed5b58ac1b59f003d88"),
-			hexEncPubkey("3dd5739c73649d510456a70e9d6b46a855864a4a3f744e088fd8c8da11b18e4c9b5f2d7da50b1c147b2bae5ca9609ae01f7a3cdea9dce34f80a91d29cd82f918"),
-			hexEncPubkey("f0d7df1efc439b4bcc0b762118c1cfa99b2a6143a9f4b10e3c9465125f4c9fca4ab88a2504169bbcad65492cf2f50da9dd5d077c39574a944f94d8246529066b"),
-			hexEncPubkey("dd598b9ba441448e5fb1a6ec6c5f5aa9605bad6e223297c729b1705d11d05f6bfd3d41988b694681ae69bb03b9a08bff4beab5596503d12a39bffb5cd6e94c7c"),
-			hexEncPubkey("3fce284ac97e567aebae681b15b7a2b6df9d873945536335883e4bbc26460c064370537f323fd1ada828ea43154992d14ac0cec0940a2bd2a3f42ec156d60c83"),
-			hexEncPubkey("7c8dfa8c1311cb14fb29a8ac11bca23ecc115e56d9fcf7b7ac1db9066aa4eb39f8b1dabf46e192a65be95ebfb4e839b5ab4533fef414921825e996b210dd53bd"),
-			hexEncPubkey("cafa6934f82120456620573d7f801390ed5e16ed619613a37e409e44ab355ef755e83565a913b48a9466db786f8d4fbd590bfec474c2524d4a2608d4eafd6abd"),
-			hexEncPubkey("9d16600d0dd310d77045769fed2cb427f32db88cd57d86e49390c2ba8a9698cfa856f775be2013237226e7bf47b248871cf865d23015937d1edeb20db5e3e760"),
-			hexEncPubkey("17be6b6ba54199b1d80eff866d348ea11d8a4b341d63ad9a6681d3ef8a43853ac564d153eb2a8737f0afc9ab320f6f95c55aa11aaa13bbb1ff422fd16bdf8188"),
-		},
-	},
-}
-
-type preminedTestnet struct {
-	target    encPubkey
-	targetSha enode.ID // sha3(target)
-	dists     [hashBits + 1][]encPubkey
-}
-
-func (tn *preminedTestnet) self() *enode.Node {
-	return nullNode
-}
-
-func (tn *preminedTestnet) findnode(toid enode.ID, toaddr *net.UDPAddr, target encPubkey) ([]*node, error) {
-	// current log distance is encoded in port number
-	// fmt.Println("findnode query at dist", toaddr.Port)
-	if toaddr.Port == 0 {
-		panic("query to node at distance 0")
-	}
-	next := toaddr.Port - 1
-	var result []*node
-	for i, ekey := range tn.dists[toaddr.Port] {
-		key, _ := decodePubkey(ekey)
-		node := wrapNode(enode.NewV4(key, net.ParseIP("127.0.0.1"), i, next))
-		result = append(result, node)
-	}
-	return result, nil
-}
-
-func (*preminedTestnet) close()                                        {}
-func (*preminedTestnet) ping(toid enode.ID, toaddr *net.UDPAddr) error { return nil }
-
-var _ = (*preminedTestnet).mine // avoid linter warning about mine being dead code.
-
-// mine generates a testnet struct literal with nodes at
-// various distances to the given target.
-func (tn *preminedTestnet) mine(target encPubkey) {
-	tn.target = target
-	tn.targetSha = tn.target.id()
-	found := 0
-	for found < bucketSize*10 {
-		k := newkey()
-		key := encodePubkey(&k.PublicKey)
-		ld := enode.LogDist(tn.targetSha, key.id())
-		if len(tn.dists[ld]) < bucketSize {
-			tn.dists[ld] = append(tn.dists[ld], key)
-			fmt.Println("found ID with ld", ld)
-			found++
-		}
-	}
-	fmt.Println("&preminedTestnet{")
-	fmt.Printf("	target: %#v,\n", tn.target)
-	fmt.Printf("	targetSha: %#v,\n", tn.targetSha)
-	fmt.Printf("	dists: [%d][]encPubkey{\n", len(tn.dists))
-	for ld, ns := range tn.dists {
-		if len(ns) == 0 {
-			continue
-		}
-		fmt.Printf("		%d: []encPubkey{\n", ld)
-		for _, n := range ns {
-			fmt.Printf("			hexEncPubkey(\"%x\"),\n", n[:])
-		}
-		fmt.Println("		},")
-	}
-	fmt.Println("	},")
-	fmt.Println("}")
-}
-
 // gen wraps quick.Value so it's easier to use.
 // it generates a random value of the given value's type.
 func gen(typ interface{}, rand *rand.Rand) interface{} {

p2p/discover/table_util_test.go

@@ -17,12 +17,16 @@
 package discover
 
 import (
+	"crypto/ecdsa"
 	"encoding/hex"
 	"fmt"
 	"math/rand"
 	"net"
+	"sort"
 	"sync"
 
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/p2p/enr"
 )
@@ -37,7 +41,7 @@ func init() {
 
 func newTestTable(t transport) (*Table, *enode.DB) {
 	db, _ := enode.OpenDB("")
-	tab, _ := newTable(t, db, nil)
+	tab, _ := newTable(t, db, nil, log.Root())
 	return tab, db
 }
 
@@ -108,26 +112,30 @@ func newPingRecorder() *pingRecorder {
 	}
 }
 
-func (t *pingRecorder) self() *enode.Node {
+func (t *pingRecorder) Self() *enode.Node {
 	return nullNode
 }
 
-func (t *pingRecorder) findnode(toid enode.ID, toaddr *net.UDPAddr, target encPubkey) ([]*node, error) {
-	return nil, nil
-}
-
-func (t *pingRecorder) ping(toid enode.ID, toaddr *net.UDPAddr) error {
+func (t *pingRecorder) ping(n *enode.Node) error {
 	t.mu.Lock()
 	defer t.mu.Unlock()
 
-	t.pinged[toid] = true
-	if t.dead[toid] {
+	t.pinged[n.ID()] = true
+	if t.dead[n.ID()] {
 		return errTimeout
 	} else {
 		return nil
 	}
 }
 
+func (t *pingRecorder) lookupSelf() []*enode.Node {
+	return nil
+}
+
+func (t *pingRecorder) lookupRandom() []*enode.Node {
+	return nil
+}
+
 func (t *pingRecorder) close() {}
 
 func hasDuplicates(slice []*node) bool {
@@ -145,14 +153,21 @@ func hasDuplicates(slice []*node) bool {
 }
 
 func sortedByDistanceTo(distbase enode.ID, slice []*node) bool {
-	var last enode.ID
-	for i, e := range slice {
-		if i > 0 && enode.DistCmp(distbase, e.ID(), last) < 0 {
-			return false
-		}
-		last = e.ID()
+	return sort.SliceIsSorted(slice, func(i, j int) bool {
+		return enode.DistCmp(distbase, slice[i].ID(), slice[j].ID()) < 0
+	})
+}
+
+func hexEncPrivkey(h string) *ecdsa.PrivateKey {
+	b, err := hex.DecodeString(h)
+	if err != nil {
+		panic(err)
 	}
-	return true
+	key, err := crypto.ToECDSA(b)
+	if err != nil {
+		panic(err)
+	}
+	return key
 }
 
 func hexEncPubkey(h string) (ret encPubkey) {

p2p/discover/v4_udp.go

@@ -20,8 +20,10 @@ import (
 	"bytes"
 	"container/list"
 	"crypto/ecdsa"
+	crand "crypto/rand"
 	"errors"
 	"fmt"
+	"io"
 	"net"
 	"sync"
 	"time"
@@ -63,15 +65,15 @@ const (
 
 // RPC packet types
 const (
-	pingPacket = iota + 1 // zero is 'reserved'
-	pongPacket
-	findnodePacket
-	neighborsPacket
+	p_pingV4 = iota + 1 // zero is 'reserved'
+	p_pongV4
+	p_findnodeV4
+	p_neighborsV4
 )
 
 // RPC request structures
 type (
-	ping struct {
+	pingV4 struct {
 		senderKey *ecdsa.PublicKey // filled in by preverify
 
 		Version    uint
@@ -81,8 +83,8 @@ type (
 		Rest []rlp.RawValue `rlp:"tail"`
 	}
 
-	// pong is the reply to ping.
-	pong struct {
+	// pongV4 is the reply to pingV4.
+	pongV4 struct {
 		// This field should mirror the UDP envelope address
 		// of the ping packet, which provides a way to discover the
 		// the external address (after NAT).
@@ -94,16 +96,16 @@ type (
 		Rest []rlp.RawValue `rlp:"tail"`
 	}
 
-	// findnode is a query for nodes close to the given target.
-	findnode struct {
+	// findnodeV4 is a query for nodes close to the given target.
+	findnodeV4 struct {
 		Target     encPubkey
 		Expiration uint64
 		// Ignore additional fields (for forward compatibility).
 		Rest []rlp.RawValue `rlp:"tail"`
 	}
 
-	// reply to findnode
-	neighbors struct {
+	// neighborsV4 is the reply to findnodeV4.
+	neighborsV4 struct {
 		Nodes      []rpcNode
 		Expiration uint64
 		// Ignore additional fields (for forward compatibility).
@@ -124,6 +126,16 @@ type (
 	}
 )
 
+// packet is implemented by all v4 protocol messages.
+type packetV4 interface {
+	// preverify checks whether the packet is valid and should be handled at all.
+	preverify(t *UDPv4, from *net.UDPAddr, fromID enode.ID, fromKey encPubkey) error
+	// handle handles the packet.
+	handle(t *UDPv4, from *net.UDPAddr, fromID enode.ID, mac []byte)
+	// name returns the name of the packet for logging purposes.
+	name() string
+}
+
 func makeEndpoint(addr *net.UDPAddr, tcpPort uint16) rpcEndpoint {
 	ip := net.IP{}
 	if ip4 := addr.IP.To4(); ip4 != nil {
@@ -134,7 +146,7 @@ func makeEndpoint(addr *net.UDPAddr, tcpPort uint16) rpcEndpoint {
 	return rpcEndpoint{IP: ip, UDP: uint16(addr.Port), TCP: tcpPort}
 }
 
-func (t *udp) nodeFromRPC(sender *net.UDPAddr, rn rpcNode) (*node, error) {
+func (t *UDPv4) nodeFromRPC(sender *net.UDPAddr, rn rpcNode) (*node, error) {
 	if rn.UDP <= 1024 {
 		return nil, errors.New("low port")
 	}
@@ -162,31 +174,16 @@ func nodeToRPC(n *node) rpcNode {
 	return rpcNode{ID: ekey, IP: n.IP(), UDP: uint16(n.UDP()), TCP: uint16(n.TCP())}
 }
 
-// packet is implemented by all protocol messages.
-type packet interface {
-	// preverify checks whether the packet is valid and should be handled at all.
-	preverify(t *udp, from *net.UDPAddr, fromID enode.ID, fromKey encPubkey) error
-	// handle handles the packet.
-	handle(t *udp, from *net.UDPAddr, fromID enode.ID, mac []byte)
-	// name returns the name of the packet for logging purposes.
-	name() string
-}
-
-type conn interface {
-	ReadFromUDP(b []byte) (n int, addr *net.UDPAddr, err error)
-	WriteToUDP(b []byte, addr *net.UDPAddr) (n int, err error)
-	Close() error
-	LocalAddr() net.Addr
-}
-
-// udp implements the discovery v4 UDP wire protocol.
-type udp struct {
-	conn        conn
+// UDPv4 implements the v4 wire protocol.
+type UDPv4 struct {
+	conn        UDPConn
+	log         log.Logger
 	netrestrict *netutil.Netlist
 	priv        *ecdsa.PrivateKey
 	localNode   *enode.LocalNode
 	db          *enode.DB
 	tab         *Table
+	closeOnce   sync.Once
 	wg          sync.WaitGroup
 
 	addReplyMatcher chan *replyMatcher
@@ -229,41 +226,15 @@ type reply struct {
 	from  enode.ID
 	ip    net.IP
 	ptype byte
-	data  packet
+	data  packetV4
 
 	// loop indicates whether there was
 	// a matching request by sending on this channel.
 	matched chan<- bool
 }
 
-// ReadPacket is sent to the unhandled channel when it could not be processed
-type ReadPacket struct {
-	Data []byte
-	Addr *net.UDPAddr
-}
-
-// Config holds Table-related settings.
-type Config struct {
-	// These settings are required and configure the UDP listener:
-	PrivateKey *ecdsa.PrivateKey
-
-	// These settings are optional:
-	NetRestrict *netutil.Netlist  // network whitelist
-	Bootnodes   []*enode.Node     // list of bootstrap nodes
-	Unhandled   chan<- ReadPacket // unhandled packets are sent on this channel
-}
-
-// ListenUDP returns a new table that listens for UDP packets on laddr.
-func ListenUDP(c conn, ln *enode.LocalNode, cfg Config) (*Table, error) {
-	tab, _, err := newUDP(c, ln, cfg)
-	if err != nil {
-		return nil, err
-	}
-	return tab, nil
-}
-
-func newUDP(c conn, ln *enode.LocalNode, cfg Config) (*Table, *udp, error) {
-	udp := &udp{
+func ListenV4(c UDPConn, ln *enode.LocalNode, cfg Config) (*UDPv4, error) {
+	t := &UDPv4{
 		conn:            c,
 		priv:            cfg.PrivateKey,
 		netrestrict:     cfg.NetRestrict,
@@ -272,50 +243,190 @@ func newUDP(c conn, ln *enode.LocalNode, cfg Config) (*Table, *udp, error) {
 		closing:         make(chan struct{}),
 		gotreply:        make(chan reply),
 		addReplyMatcher: make(chan *replyMatcher),
+		log:             cfg.Log,
 	}
-	tab, err := newTable(udp, ln.Database(), cfg.Bootnodes)
+	if t.log == nil {
+		t.log = log.Root()
+	}
+	tab, err := newTable(t, ln.Database(), cfg.Bootnodes, t.log)
 	if err != nil {
-		return nil, nil, err
+		return nil, err
 	}
-	udp.tab = tab
+	t.tab = tab
 
-	udp.wg.Add(2)
-	go udp.loop()
-	go udp.readLoop(cfg.Unhandled)
-	return udp.tab, udp, nil
+	t.wg.Add(2)
+	go t.loop()
+	go t.readLoop(cfg.Unhandled)
+	return t, nil
 }
 
-func (t *udp) self() *enode.Node {
+// Self returns the local node.
+func (t *UDPv4) Self() *enode.Node {
 	return t.localNode.Node()
 }
 
-func (t *udp) close() {
-	close(t.closing)
-	t.conn.Close()
-	t.wg.Wait()
+// Close shuts down the socket and aborts any running queries.
+func (t *UDPv4) Close() {
+	t.closeOnce.Do(func() {
+		close(t.closing)
+		t.conn.Close()
+		t.wg.Wait()
+		t.tab.close()
+	})
 }
 
-func (t *udp) ourEndpoint() rpcEndpoint {
-	n := t.self()
+// ReadRandomNodes reads random nodes from the local table.
+func (t *UDPv4) ReadRandomNodes(buf []*enode.Node) int {
+	return t.tab.ReadRandomNodes(buf)
+}
+
+// LookupRandom finds random nodes in the network.
+func (t *UDPv4) LookupRandom() []*enode.Node {
+	if t.tab.len() == 0 {
+		// All nodes were dropped, refresh. The very first query will hit this
+		// case and run the bootstrapping logic.
+		<-t.tab.refresh()
+	}
+	return t.lookupRandom()
+}
+
+func (t *UDPv4) LookupPubkey(key *ecdsa.PublicKey) []*enode.Node {
+	if t.tab.len() == 0 {
+		// All nodes were dropped, refresh. The very first query will hit this
+		// case and run the bootstrapping logic.
+		<-t.tab.refresh()
+	}
+	return unwrapNodes(t.lookup(encodePubkey(key)))
+}
+
+func (t *UDPv4) lookupRandom() []*enode.Node {
+	var target encPubkey
+	crand.Read(target[:])
+	return unwrapNodes(t.lookup(target))
+}
+
+func (t *UDPv4) lookupSelf() []*enode.Node {
+	return unwrapNodes(t.lookup(encodePubkey(&t.priv.PublicKey)))
+}
+
+// lookup performs a network search for nodes close to the given target. It approaches the
+// target by querying nodes that are closer to it on each iteration. The given target does
+// not need to be an actual node identifier.
+func (t *UDPv4) lookup(targetKey encPubkey) []*node {
+	var (
+		target         = enode.ID(crypto.Keccak256Hash(targetKey[:]))
+		asked          = make(map[enode.ID]bool)
+		seen           = make(map[enode.ID]bool)
+		reply          = make(chan []*node, alpha)
+		pendingQueries = 0
+		result         *nodesByDistance
+	)
+	// Don't query further if we hit ourself.
+	// Unlikely to happen often in practice.
+	asked[t.Self().ID()] = true
+
+	// Generate the initial result set.
+	t.tab.mutex.Lock()
+	result = t.tab.closest(target, bucketSize, false)
+	t.tab.mutex.Unlock()
+
+	for {
+		// ask the alpha closest nodes that we haven't asked yet
+		for i := 0; i < len(result.entries) && pendingQueries < alpha; i++ {
+			n := result.entries[i]
+			if !asked[n.ID()] {
+				asked[n.ID()] = true
+				pendingQueries++
+				go t.lookupWorker(n, targetKey, reply)
+			}
+		}
+		if pendingQueries == 0 {
+			// we have asked all closest nodes, stop the search
+			break
+		}
+		select {
+		case nodes := <-reply:
+			for _, n := range nodes {
+				if n != nil && !seen[n.ID()] {
+					seen[n.ID()] = true
+					result.push(n, bucketSize)
+				}
+			}
+		case <-t.tab.closeReq:
+			return nil // shutdown, no need to continue.
+		}
+		pendingQueries--
+	}
+	return result.entries
+}
+
+func (t *UDPv4) lookupWorker(n *node, targetKey encPubkey, reply chan<- []*node) {
+	fails := t.db.FindFails(n.ID(), n.IP())
+	r, err := t.findnode(n.ID(), n.addr(), targetKey)
+	if err == errClosed {
+		// Avoid recording failures on shutdown.
+		reply <- nil
+		return
+	} else if len(r) == 0 {
+		fails++
+		t.db.UpdateFindFails(n.ID(), n.IP(), fails)
+		t.log.Trace("Findnode failed", "id", n.ID(), "failcount", fails, "err", err)
+		if fails >= maxFindnodeFailures {
+			t.log.Trace("Too many findnode failures, dropping", "id", n.ID(), "failcount", fails)
+			t.tab.delete(n)
+		}
+	} else if fails > 0 {
+		t.db.UpdateFindFails(n.ID(), n.IP(), fails-1)
+	}
+
+	// Grab as many nodes as possible. Some of them might not be alive anymore, but we'll
+	// just remove those again during revalidation.
+	for _, n := range r {
+		t.tab.addSeenNode(n)
+	}
+	reply <- r
+}
+
+// Resolve searches for a specific node with the given ID.
+// It returns nil if the node could not be found.
+func (t *UDPv4) Resolve(n *enode.Node) *enode.Node {
+	// If the node is present in the local table, no
+	// network interaction is required.
+	if intab := t.tab.Resolve(n); intab != nil {
+		return intab
+	}
+	// Otherwise, do a network lookup.
+	hash := n.ID()
+	result := t.LookupPubkey(n.Pubkey())
+	for _, n := range result {
+		if n.ID() == hash {
+			return n
+		}
+	}
+	return nil
+}
+
+func (t *UDPv4) ourEndpoint() rpcEndpoint {
+	n := t.Self()
 	a := &net.UDPAddr{IP: n.IP(), Port: n.UDP()}
 	return makeEndpoint(a, uint16(n.TCP()))
 }
 
 // ping sends a ping message to the given node and waits for a reply.
-func (t *udp) ping(toid enode.ID, toaddr *net.UDPAddr) error {
-	return <-t.sendPing(toid, toaddr, nil)
+func (t *UDPv4) ping(n *enode.Node) error {
+	return <-t.sendPing(n.ID(), &net.UDPAddr{IP: n.IP(), Port: n.UDP()}, nil)
 }
 
 // sendPing sends a ping message to the given node and invokes the callback
 // when the reply arrives.
-func (t *udp) sendPing(toid enode.ID, toaddr *net.UDPAddr, callback func()) <-chan error {
-	req := &ping{
+func (t *UDPv4) sendPing(toid enode.ID, toaddr *net.UDPAddr, callback func()) <-chan error {
+	req := &pingV4{
 		Version:    4,
 		From:       t.ourEndpoint(),
 		To:         makeEndpoint(toaddr, 0), // TODO: maybe use known TCP port from DB
 		Expiration: uint64(time.Now().Add(expiration).Unix()),
 	}
-	packet, hash, err := encodePacket(t.priv, pingPacket, req)
+	packet, hash, err := t.encode(t.priv, p_pingV4, req)
 	if err != nil {
 		errc := make(chan error, 1)
 		errc <- err
@@ -323,8 +434,8 @@ func (t *udp) sendPing(toid enode.ID, toaddr *net.UDPAddr, callback func()) <-ch
 	}
 	// Add a matcher for the reply to the pending reply queue. Pongs are matched if they
 	// reference the ping we're about to send.
-	errc := t.pending(toid, toaddr.IP, pongPacket, func(p interface{}) (matched bool, requestDone bool) {
-		matched = bytes.Equal(p.(*pong).ReplyTok, hash)
+	errc := t.pending(toid, toaddr.IP, p_pongV4, func(p interface{}) (matched bool, requestDone bool) {
+		matched = bytes.Equal(p.(*pongV4).ReplyTok, hash)
 		if matched && callback != nil {
 			callback()
 		}
@@ -338,11 +449,11 @@ func (t *udp) sendPing(toid enode.ID, toaddr *net.UDPAddr, callback func()) <-ch
 
 // findnode sends a findnode request to the given node and waits until
 // the node has sent up to k neighbors.
-func (t *udp) findnode(toid enode.ID, toaddr *net.UDPAddr, target encPubkey) ([]*node, error) {
+func (t *UDPv4) findnode(toid enode.ID, toaddr *net.UDPAddr, target encPubkey) ([]*node, error) {
 	// If we haven't seen a ping from the destination node for a while, it won't remember
 	// our endpoint proof and reject findnode. Solicit a ping first.
 	if time.Since(t.db.LastPingReceived(toid, toaddr.IP)) > bondExpiration {
-		t.ping(toid, toaddr)
+		<-t.sendPing(toid, toaddr, nil)
 		// Wait for them to ping back and process our pong.
 		time.Sleep(respTimeout)
 	}
@@ -351,20 +462,20 @@ func (t *udp) findnode(toid enode.ID, toaddr *net.UDPAddr, target encPubkey) ([]
 	// active until enough nodes have been received.
 	nodes := make([]*node, 0, bucketSize)
 	nreceived := 0
-	errc := t.pending(toid, toaddr.IP, neighborsPacket, func(r interface{}) (matched bool, requestDone bool) {
-		reply := r.(*neighbors)
+	errc := t.pending(toid, toaddr.IP, p_neighborsV4, func(r interface{}) (matched bool, requestDone bool) {
+		reply := r.(*neighborsV4)
 		for _, rn := range reply.Nodes {
 			nreceived++
 			n, err := t.nodeFromRPC(toaddr, rn)
 			if err != nil {
-				log.Trace("Invalid neighbor node received", "ip", rn.IP, "addr", toaddr, "err", err)
+				t.log.Trace("Invalid neighbor node received", "ip", rn.IP, "addr", toaddr, "err", err)
 				continue
 			}
 			nodes = append(nodes, n)
 		}
 		return true, nreceived >= bucketSize
 	})
-	t.send(toaddr, toid, findnodePacket, &findnode{
+	t.send(toaddr, toid, p_findnodeV4, &findnodeV4{
 		Target:     target,
 		Expiration: uint64(time.Now().Add(expiration).Unix()),
 	})
@@ -373,7 +484,7 @@ func (t *udp) findnode(toid enode.ID, toaddr *net.UDPAddr, target encPubkey) ([]
 
 // pending adds a reply matcher to the pending reply queue.
 // see the documentation of type replyMatcher for a detailed explanation.
-func (t *udp) pending(id enode.ID, ip net.IP, ptype byte, callback replyMatchFunc) <-chan error {
+func (t *UDPv4) pending(id enode.ID, ip net.IP, ptype byte, callback replyMatchFunc) <-chan error {
 	ch := make(chan error, 1)
 	p := &replyMatcher{from: id, ip: ip, ptype: ptype, callback: callback, errc: ch}
 	select {
@@ -387,7 +498,7 @@ func (t *udp) pending(id enode.ID, ip net.IP, ptype byte, callback replyMatchFun
 
 // handleReply dispatches a reply packet, invoking reply matchers. It returns
 // whether any matcher considered the packet acceptable.
-func (t *udp) handleReply(from enode.ID, fromIP net.IP, ptype byte, req packet) bool {
+func (t *UDPv4) handleReply(from enode.ID, fromIP net.IP, ptype byte, req packetV4) bool {
 	matched := make(chan bool, 1)
 	select {
 	case t.gotreply <- reply{from, fromIP, ptype, req, matched}:
@@ -400,7 +511,7 @@ func (t *udp) handleReply(from enode.ID, fromIP net.IP, ptype byte, req packet)
 
 // loop runs in its own goroutine. it keeps track of
 // the refresh timer and the pending reply queue.
-func (t *udp) loop() {
+func (t *UDPv4) loop() {
 	defer t.wg.Done()
 
 	var (
@@ -507,7 +618,7 @@ var (
 )
 
 func init() {
-	p := neighbors{Expiration: ^uint64(0)}
+	p := neighborsV4{Expiration: ^uint64(0)}
 	maxSizeNode := rpcNode{IP: make(net.IP, 16), UDP: ^uint16(0), TCP: ^uint16(0)}
 	for n := 0; ; n++ {
 		p.Nodes = append(p.Nodes, maxSizeNode)
@@ -523,32 +634,32 @@ func init() {
 	}
 }
 
-func (t *udp) send(toaddr *net.UDPAddr, toid enode.ID, ptype byte, req packet) ([]byte, error) {
-	packet, hash, err := encodePacket(t.priv, ptype, req)
+func (t *UDPv4) send(toaddr *net.UDPAddr, toid enode.ID, ptype byte, req packetV4) ([]byte, error) {
+	packet, hash, err := t.encode(t.priv, ptype, req)
 	if err != nil {
 		return hash, err
 	}
 	return hash, t.write(toaddr, toid, req.name(), packet)
 }
 
-func (t *udp) write(toaddr *net.UDPAddr, toid enode.ID, what string, packet []byte) error {
+func (t *UDPv4) write(toaddr *net.UDPAddr, toid enode.ID, what string, packet []byte) error {
 	_, err := t.conn.WriteToUDP(packet, toaddr)
-	log.Trace(">> "+what, "id", toid, "addr", toaddr, "err", err)
+	t.log.Trace(">> "+what, "id", toid, "addr", toaddr, "err", err)
 	return err
 }
 
-func encodePacket(priv *ecdsa.PrivateKey, ptype byte, req interface{}) (packet, hash []byte, err error) {
+func (t *UDPv4) encode(priv *ecdsa.PrivateKey, ptype byte, req interface{}) (packet, hash []byte, err error) {
 	b := new(bytes.Buffer)
 	b.Write(headSpace)
 	b.WriteByte(ptype)
 	if err := rlp.Encode(b, req); err != nil {
-		log.Error("Can't encode discv4 packet", "err", err)
+		t.log.Error("Can't encode discv4 packet", "err", err)
 		return nil, nil, err
 	}
 	packet = b.Bytes()
 	sig, err := crypto.Sign(crypto.Keccak256(packet[headSize:]), priv)
 	if err != nil {
-		log.Error("Can't sign discv4 packet", "err", err)
+		t.log.Error("Can't sign discv4 packet", "err", err)
 		return nil, nil, err
 	}
 	copy(packet[macSize:], sig)
@@ -561,7 +672,7 @@ func encodePacket(priv *ecdsa.PrivateKey, ptype byte, req interface{}) (packet,
 }
 
 // readLoop runs in its own goroutine. it handles incoming UDP packets.
-func (t *udp) readLoop(unhandled chan<- ReadPacket) {
+func (t *UDPv4) readLoop(unhandled chan<- ReadPacket) {
 	defer t.wg.Done()
 	if unhandled != nil {
 		defer close(unhandled)
@@ -572,11 +683,13 @@ func (t *udp) readLoop(unhandled chan<- ReadPacket) {
 		nbytes, from, err := t.conn.ReadFromUDP(buf)
 		if netutil.IsTemporaryError(err) {
 			// Ignore temporary read errors.
-			log.Debug("Temporary UDP read error", "err", err)
+			t.log.Debug("Temporary UDP read error", "err", err)
 			continue
 		} else if err != nil {
 			// Shut down the loop for permament errors.
-			log.Debug("UDP read error", "err", err)
+			if err != io.EOF {
+				t.log.Debug("UDP read error", "err", err)
+			}
 			return
 		}
 		if t.handlePacket(from, buf[:nbytes]) != nil && unhandled != nil {
@@ -588,24 +701,24 @@ func (t *udp) readLoop(unhandled chan<- ReadPacket) {
 	}
 }
 
-func (t *udp) handlePacket(from *net.UDPAddr, buf []byte) error {
-	packet, fromKey, hash, err := decodePacket(buf)
+func (t *UDPv4) handlePacket(from *net.UDPAddr, buf []byte) error {
+	packet, fromKey, hash, err := decodeV4(buf)
 	if err != nil {
-		log.Debug("Bad discv4 packet", "addr", from, "err", err)
+		t.log.Debug("Bad discv4 packet", "addr", from, "err", err)
 		return err
 	}
 	fromID := fromKey.id()
 	if err == nil {
 		err = packet.preverify(t, from, fromID, fromKey)
 	}
-	log.Trace("<< "+packet.name(), "id", fromID, "addr", from, "err", err)
+	t.log.Trace("<< "+packet.name(), "id", fromID, "addr", from, "err", err)
 	if err == nil {
 		packet.handle(t, from, fromID, hash)
 	}
 	return err
 }
 
-func decodePacket(buf []byte) (packet, encPubkey, []byte, error) {
+func decodeV4(buf []byte) (packetV4, encPubkey, []byte, error) {
 	if len(buf) < headSize+1 {
 		return nil, encPubkey{}, nil, errPacketTooSmall
 	}
@@ -619,16 +732,16 @@ func decodePacket(buf []byte) (packet, encPubkey, []byte, error) {
 		return nil, fromKey, hash, err
 	}
 
-	var req packet
+	var req packetV4
 	switch ptype := sigdata[0]; ptype {
-	case pingPacket:
-		req = new(ping)
-	case pongPacket:
-		req = new(pong)
-	case findnodePacket:
-		req = new(findnode)
-	case neighborsPacket:
-		req = new(neighbors)
+	case p_pingV4:
+		req = new(pingV4)
+	case p_pongV4:
+		req = new(pongV4)
+	case p_findnodeV4:
+		req = new(findnodeV4)
+	case p_neighborsV4:
+		req = new(neighborsV4)
 	default:
 		return nil, fromKey, hash, fmt.Errorf("unknown type: %d", ptype)
 	}
@@ -639,7 +752,7 @@ func decodePacket(buf []byte) (packet, encPubkey, []byte, error) {
 
 // Packet Handlers
 
-func (req *ping) preverify(t *udp, from *net.UDPAddr, fromID enode.ID, fromKey encPubkey) error {
+func (req *pingV4) preverify(t *UDPv4, from *net.UDPAddr, fromID enode.ID, fromKey encPubkey) error {
 	if expired(req.Expiration) {
 		return errExpired
 	}
@@ -651,9 +764,9 @@ func (req *ping) preverify(t *udp, from *net.UDPAddr, fromID enode.ID, fromKey e
 	return nil
 }
 
-func (req *ping) handle(t *udp, from *net.UDPAddr, fromID enode.ID, mac []byte) {
+func (req *pingV4) handle(t *UDPv4, from *net.UDPAddr, fromID enode.ID, mac []byte) {
 	// Reply.
-	t.send(from, fromID, pongPacket, &pong{
+	t.send(from, fromID, p_pongV4, &pongV4{
 		To:         makeEndpoint(from, req.From.TCP),
 		ReplyTok:   mac,
 		Expiration: uint64(time.Now().Add(expiration).Unix()),
@@ -674,26 +787,26 @@ func (req *ping) handle(t *udp, from *net.UDPAddr, fromID enode.ID, mac []byte)
 	t.localNode.UDPEndpointStatement(from, &net.UDPAddr{IP: req.To.IP, Port: int(req.To.UDP)})
 }
 
-func (req *ping) name() string { return "PING/v4" }
+func (req *pingV4) name() string { return "PING/v4" }
 
-func (req *pong) preverify(t *udp, from *net.UDPAddr, fromID enode.ID, fromKey encPubkey) error {
+func (req *pongV4) preverify(t *UDPv4, from *net.UDPAddr, fromID enode.ID, fromKey encPubkey) error {
 	if expired(req.Expiration) {
 		return errExpired
 	}
-	if !t.handleReply(fromID, from.IP, pongPacket, req) {
+	if !t.handleReply(fromID, from.IP, p_pongV4, req) {
 		return errUnsolicitedReply
 	}
 	return nil
 }
 
-func (req *pong) handle(t *udp, from *net.UDPAddr, fromID enode.ID, mac []byte) {
+func (req *pongV4) handle(t *UDPv4, from *net.UDPAddr, fromID enode.ID, mac []byte) {
 	t.localNode.UDPEndpointStatement(from, &net.UDPAddr{IP: req.To.IP, Port: int(req.To.UDP)})
 	t.db.UpdateLastPongReceived(fromID, from.IP, time.Now())
 }
 
-func (req *pong) name() string { return "PONG/v4" }
+func (req *pongV4) name() string { return "PONG/v4" }
 
-func (req *findnode) preverify(t *udp, from *net.UDPAddr, fromID enode.ID, fromKey encPubkey) error {
+func (req *findnodeV4) preverify(t *UDPv4, from *net.UDPAddr, fromID enode.ID, fromKey encPubkey) error {
 	if expired(req.Expiration) {
 		return errExpired
 	}
@@ -709,48 +822,48 @@ func (req *findnode) preverify(t *udp, from *net.UDPAddr, fromID enode.ID, fromK
 	return nil
 }
 
-func (req *findnode) handle(t *udp, from *net.UDPAddr, fromID enode.ID, mac []byte) {
+func (req *findnodeV4) handle(t *UDPv4, from *net.UDPAddr, fromID enode.ID, mac []byte) {
 	// Determine closest nodes.
 	target := enode.ID(crypto.Keccak256Hash(req.Target[:]))
 	t.tab.mutex.Lock()
-	closest := t.tab.closest(target, bucketSize).entries
+	closest := t.tab.closest(target, bucketSize, true).entries
 	t.tab.mutex.Unlock()
 
 	// Send neighbors in chunks with at most maxNeighbors per packet
 	// to stay below the packet size limit.
-	p := neighbors{Expiration: uint64(time.Now().Add(expiration).Unix())}
+	p := neighborsV4{Expiration: uint64(time.Now().Add(expiration).Unix())}
 	var sent bool
 	for _, n := range closest {
 		if netutil.CheckRelayIP(from.IP, n.IP()) == nil {
 			p.Nodes = append(p.Nodes, nodeToRPC(n))
 		}
 		if len(p.Nodes) == maxNeighbors {
-			t.send(from, fromID, neighborsPacket, &p)
+			t.send(from, fromID, p_neighborsV4, &p)
 			p.Nodes = p.Nodes[:0]
 			sent = true
 		}
 	}
 	if len(p.Nodes) > 0 || !sent {
-		t.send(from, fromID, neighborsPacket, &p)
+		t.send(from, fromID, p_neighborsV4, &p)
 	}
 }
 
-func (req *findnode) name() string { return "FINDNODE/v4" }
+func (req *findnodeV4) name() string { return "FINDNODE/v4" }
 
-func (req *neighbors) preverify(t *udp, from *net.UDPAddr, fromID enode.ID, fromKey encPubkey) error {
+func (req *neighborsV4) preverify(t *UDPv4, from *net.UDPAddr, fromID enode.ID, fromKey encPubkey) error {
 	if expired(req.Expiration) {
 		return errExpired
 	}
-	if !t.handleReply(fromID, from.IP, neighborsPacket, req) {
+	if !t.handleReply(fromID, from.IP, p_neighborsV4, req) {
 		return errUnsolicitedReply
 	}
 	return nil
 }
 
-func (req *neighbors) handle(t *udp, from *net.UDPAddr, fromID enode.ID, mac []byte) {
+func (req *neighborsV4) handle(t *UDPv4, from *net.UDPAddr, fromID enode.ID, mac []byte) {
 }
 
-func (req *neighbors) name() string { return "NEIGHBORS/v4" }
+func (req *neighborsV4) name() string { return "NEIGHBORS/v4" }
 
 func expired(ts uint64) bool {
 	return time.Unix(int64(ts), 0).Before(time.Now())

p2p/discover/v4_udp_lookup_test.go

@@ -0,0 +1,220 @@
+// Copyright 2019 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 discover
+
+import (
+	"crypto/ecdsa"
+	"fmt"
+	"net"
+	"reflect"
+	"sort"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/p2p/enode"
+)
+
+func TestUDPv4_Lookup(t *testing.T) {
+	t.Parallel()
+	test := newUDPTest(t)
+
+	// Lookup on empty table returns no nodes.
+	targetKey, _ := decodePubkey(lookupTestnet.target)
+	if results := test.udp.LookupPubkey(targetKey); len(results) > 0 {
+		t.Fatalf("lookup on empty table returned %d results: %#v", len(results), results)
+	}
+
+	// Seed table with initial node.
+	fillTable(test.table, []*node{wrapNode(lookupTestnet.node(256, 0))})
+
+	// Start the lookup.
+	resultC := make(chan []*enode.Node, 1)
+	go func() {
+		resultC <- test.udp.LookupPubkey(targetKey)
+		test.close()
+	}()
+
+	// Answer lookup packets.
+	for done := false; !done; {
+		done = test.waitPacketOut(func(p packetV4, to *net.UDPAddr, hash []byte) {
+			n, key := lookupTestnet.nodeByAddr(to)
+			switch p.(type) {
+			case *pingV4:
+				test.packetInFrom(nil, key, to, p_pongV4, &pongV4{Expiration: futureExp, ReplyTok: hash})
+			case *findnodeV4:
+				dist := enode.LogDist(n.ID(), lookupTestnet.target.id())
+				nodes := lookupTestnet.nodesAtDistance(dist - 1)
+				test.packetInFrom(nil, key, to, p_neighborsV4, &neighborsV4{Expiration: futureExp, Nodes: nodes})
+			}
+		})
+	}
+
+	// Verify result nodes.
+	results := <-resultC
+	t.Logf("results:")
+	for _, e := range results {
+		t.Logf("  ld=%d, %x", enode.LogDist(lookupTestnet.target.id(), e.ID()), e.ID().Bytes())
+	}
+	if len(results) != bucketSize {
+		t.Errorf("wrong number of results: got %d, want %d", len(results), bucketSize)
+	}
+	if hasDuplicates(wrapNodes(results)) {
+		t.Errorf("result set contains duplicate entries")
+	}
+	if !sortedByDistanceTo(lookupTestnet.target.id(), wrapNodes(results)) {
+		t.Errorf("result set not sorted by distance to target")
+	}
+	if !reflect.DeepEqual(results, lookupTestnet.closest(bucketSize)) {
+		t.Errorf("results aren't the closest %d nodes", bucketSize)
+	}
+}
+
+// This is the test network for the Lookup test.
+// The nodes were obtained by running lookupTestnet.mine with a random NodeID as target.
+var lookupTestnet = &preminedTestnet{
+	target: hexEncPubkey("5d485bdcbe9bc89314a10ae9231e429d33853e3a8fa2af39f5f827370a2e4185e344ace5d16237491dad41f278f1d3785210d29ace76cd627b9147ee340b1125"),
+	dists: [257][]*ecdsa.PrivateKey{
+		251: {
+			hexEncPrivkey("29738ba0c1a4397d6a65f292eee07f02df8e58d41594ba2be3cf84ce0fc58169"),
+			hexEncPrivkey("511b1686e4e58a917f7f848e9bf5539d206a68f5ad6b54b552c2399fe7d174ae"),
+			hexEncPrivkey("d09e5eaeec0fd596236faed210e55ef45112409a5aa7f3276d26646080dcfaeb"),
+			hexEncPrivkey("c1e20dbbf0d530e50573bd0a260b32ec15eb9190032b4633d44834afc8afe578"),
+			hexEncPrivkey("ed5f38f5702d92d306143e5d9154fb21819777da39af325ea359f453d179e80b"),
+		},
+		252: {
+			hexEncPrivkey("1c9b1cafbec00848d2c174b858219914b42a7d5c9359b1ca03fd650e8239ae94"),
+			hexEncPrivkey("e0e1e8db4a6f13c1ffdd3e96b72fa7012293ced187c9dcdcb9ba2af37a46fa10"),
+			hexEncPrivkey("3d53823e0a0295cb09f3e11d16c1b44d07dd37cec6f739b8df3a590189fe9fb9"),
+		},
+		253: {
+			hexEncPrivkey("2d0511ae9bf590166597eeab86b6f27b1ab761761eaea8965487b162f8703847"),
+			hexEncPrivkey("6cfbd7b8503073fc3dbdb746a7c672571648d3bd15197ccf7f7fef3d904f53a2"),
+			hexEncPrivkey("a30599b12827b69120633f15b98a7f6bc9fc2e9a0fd6ae2ebb767c0e64d743ab"),
+			hexEncPrivkey("14a98db9b46a831d67eff29f3b85b1b485bb12ae9796aea98d91be3dc78d8a91"),
+			hexEncPrivkey("2369ff1fc1ff8ca7d20b17e2673adc3365c3674377f21c5d9dafaff21fe12e24"),
+			hexEncPrivkey("9ae91101d6b5048607f41ec0f690ef5d09507928aded2410aabd9237aa2727d7"),
+			hexEncPrivkey("05e3c59090a3fd1ae697c09c574a36fcf9bedd0afa8fe3946f21117319ca4973"),
+			hexEncPrivkey("06f31c5ea632658f718a91a1b1b9ae4b7549d7b3bc61cbc2be5f4a439039f3ad"),
+		},
+		254: {
+			hexEncPrivkey("dec742079ec00ff4ec1284d7905bc3de2366f67a0769431fd16f80fd68c58a7c"),
+			hexEncPrivkey("ff02c8861fa12fbd129d2a95ea663492ef9c1e51de19dcfbbfe1c59894a28d2b"),
+			hexEncPrivkey("4dded9e4eefcbce4262be4fd9e8a773670ab0b5f448f286ec97dfc8cf681444a"),
+			hexEncPrivkey("750d931e2a8baa2c9268cb46b7cd851f4198018bed22f4dceb09dd334a2395f6"),
+			hexEncPrivkey("ce1435a956a98ffec484cd11489c4f165cf1606819ab6b521cee440f0c677e9e"),
+			hexEncPrivkey("996e7f8d1638be92d7328b4770f47e5420fc4bafecb4324fd33b1f5d9f403a75"),
+			hexEncPrivkey("ebdc44e77a6cc0eb622e58cf3bb903c3da4c91ca75b447b0168505d8fc308b9c"),
+			hexEncPrivkey("46bd1eddcf6431bea66fc19ebc45df191c1c7d6ed552dcdc7392885009c322f0"),
+		},
+		255: {
+			hexEncPrivkey("da8645f90826e57228d9ea72aff84500060ad111a5d62e4af831ed8e4b5acfb8"),
+			hexEncPrivkey("3c944c5d9af51d4c1d43f5d0f3a1a7ef65d5e82744d669b58b5fed242941a566"),
+			hexEncPrivkey("5ebcde76f1d579eebf6e43b0ffe9157e65ffaa391175d5b9aa988f47df3e33da"),
+			hexEncPrivkey("97f78253a7d1d796e4eaabce721febcc4550dd68fb11cc818378ba807a2cb7de"),
+			hexEncPrivkey("a38cd7dc9b4079d1c0406afd0fdb1165c285f2c44f946eca96fc67772c988c7d"),
+			hexEncPrivkey("d64cbb3ffdf712c372b7a22a176308ef8f91861398d5dbaf326fd89c6eaeef1c"),
+			hexEncPrivkey("d269609743ef29d6446e3355ec647e38d919c82a4eb5837e442efd7f4218944f"),
+			hexEncPrivkey("d8f7bcc4a530efde1d143717007179e0d9ace405ddaaf151c4d863753b7fd64c"),
+		},
+		256: {
+			hexEncPrivkey("8c5b422155d33ea8e9d46f71d1ad3e7b24cb40051413ffa1a81cff613d243ba9"),
+			hexEncPrivkey("937b1af801def4e8f5a3a8bd225a8bcff1db764e41d3e177f2e9376e8dd87233"),
+			hexEncPrivkey("120260dce739b6f71f171da6f65bc361b5fad51db74cf02d3e973347819a6518"),
+			hexEncPrivkey("1fa56cf25d4b46c2bf94e82355aa631717b63190785ac6bae545a88aadc304a9"),
+			hexEncPrivkey("3c38c503c0376f9b4adcbe935d5f4b890391741c764f61b03cd4d0d42deae002"),
+			hexEncPrivkey("3a54af3e9fa162bc8623cdf3e5d9b70bf30ade1d54cc3abea8659aba6cff471f"),
+			hexEncPrivkey("6799a02ea1999aefdcbcc4d3ff9544478be7365a328d0d0f37c26bd95ade0cda"),
+			hexEncPrivkey("e24a7bc9051058f918646b0f6e3d16884b2a55a15553b89bab910d55ebc36116"),
+		},
+	},
+}
+
+type preminedTestnet struct {
+	target encPubkey
+	dists  [hashBits + 1][]*ecdsa.PrivateKey
+}
+
+func (tn *preminedTestnet) node(dist, index int) *enode.Node {
+	key := tn.dists[dist][index]
+	ip := net.IP{127, byte(dist >> 8), byte(dist), byte(index)}
+	return enode.NewV4(&key.PublicKey, ip, 0, 5000)
+}
+
+func (tn *preminedTestnet) nodeByAddr(addr *net.UDPAddr) (*enode.Node, *ecdsa.PrivateKey) {
+	dist := int(addr.IP[1])<<8 + int(addr.IP[2])
+	index := int(addr.IP[3])
+	key := tn.dists[dist][index]
+	return tn.node(dist, index), key
+}
+
+func (tn *preminedTestnet) nodesAtDistance(dist int) []rpcNode {
+	result := make([]rpcNode, len(tn.dists[dist]))
+	for i := range result {
+		result[i] = nodeToRPC(wrapNode(tn.node(dist, i)))
+	}
+	return result
+}
+
+func (tn *preminedTestnet) closest(n int) (nodes []*enode.Node) {
+	for d := range tn.dists {
+		for i := range tn.dists[d] {
+			nodes = append(nodes, tn.node(d, i))
+		}
+	}
+	sort.Slice(nodes, func(i, j int) bool {
+		return enode.DistCmp(tn.target.id(), nodes[i].ID(), nodes[j].ID()) < 0
+	})
+	return nodes[:n]
+}
+
+var _ = (*preminedTestnet).mine // avoid linter warning about mine being dead code.
+
+// mine generates a testnet struct literal with nodes at
+// various distances to the network's target.
+func (tn *preminedTestnet) mine() {
+	// Clear existing slices first (useful when re-mining).
+	for i := range tn.dists {
+		tn.dists[i] = nil
+	}
+
+	targetSha := tn.target.id()
+	found, need := 0, 40
+	for found < need {
+		k := newkey()
+		ld := enode.LogDist(targetSha, encodePubkey(&k.PublicKey).id())
+		if len(tn.dists[ld]) < 8 {
+			tn.dists[ld] = append(tn.dists[ld], k)
+			found++
+			fmt.Printf("found ID with ld %d (%d/%d)\n", ld, found, need)
+		}
+	}
+	fmt.Printf("&preminedTestnet{\n")
+	fmt.Printf("	target: hexEncPubkey(\"%x\"),\n", tn.target[:])
+	fmt.Printf("	dists: [%d][]*ecdsa.PrivateKey{\n", len(tn.dists))
+	for ld, ns := range tn.dists {
+		if len(ns) == 0 {
+			continue
+		}
+		fmt.Printf("		%d: {\n", ld)
+		for _, key := range ns {
+			fmt.Printf("			hexEncPrivkey(\"%x\"),\n", crypto.FromECDSA(key))
+		}
+		fmt.Printf("		},\n")
+	}
+	fmt.Printf("	},\n")
+	fmt.Printf("}\n")
+}

p2p/discover/v4_udp_test.go

@@ -23,13 +23,10 @@ import (
 	"encoding/binary"
 	"encoding/hex"
 	"errors"
-	"fmt"
 	"io"
 	"math/rand"
 	"net"
-	"path/filepath"
 	"reflect"
-	"runtime"
 	"sync"
 	"testing"
 	"time"
@@ -37,6 +34,8 @@ import (
 	"github.com/davecgh/go-spew/spew"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/internal/testlog"
+	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/rlp"
 )
@@ -59,7 +58,7 @@ type udpTest struct {
 	pipe                *dgramPipe
 	table               *Table
 	db                  *enode.DB
-	udp                 *udp
+	udp                 *UDPv4
 	sent                [][]byte
 	localkey, remotekey *ecdsa.PrivateKey
 	remoteaddr          *net.UDPAddr
@@ -73,91 +72,93 @@ func newUDPTest(t *testing.T) *udpTest {
 		remotekey:  newkey(),
 		remoteaddr: &net.UDPAddr{IP: net.IP{10, 0, 1, 99}, Port: 30303},
 	}
+
 	test.db, _ = enode.OpenDB("")
 	ln := enode.NewLocalNode(test.db, test.localkey)
-	test.table, test.udp, _ = newUDP(test.pipe, ln, Config{PrivateKey: test.localkey})
+	test.udp, _ = ListenV4(test.pipe, ln, Config{
+		PrivateKey: test.localkey,
+		Log:        testlog.Logger(t, log.LvlTrace),
+	})
+	test.table = test.udp.tab
 	// Wait for initial refresh so the table doesn't send unexpected findnode.
 	<-test.table.initDone
 	return test
 }
 
 func (test *udpTest) close() {
-	test.table.Close()
+	test.udp.Close()
 	test.db.Close()
 }
 
 // handles a packet as if it had been sent to the transport.
-func (test *udpTest) packetIn(wantError error, ptype byte, data packet) error {
-	return test.packetInFrom(wantError, test.remotekey, test.remoteaddr, ptype, data)
+func (test *udpTest) packetIn(wantError error, ptype byte, data packetV4) {
+	test.t.Helper()
+
+	test.packetInFrom(wantError, test.remotekey, test.remoteaddr, ptype, data)
 }
 
 // handles a packet as if it had been sent to the transport by the key/endpoint.
-func (test *udpTest) packetInFrom(wantError error, key *ecdsa.PrivateKey, addr *net.UDPAddr, ptype byte, data packet) error {
-	enc, _, err := encodePacket(key, ptype, data)
+func (test *udpTest) packetInFrom(wantError error, key *ecdsa.PrivateKey, addr *net.UDPAddr, ptype byte, data packetV4) {
+	test.t.Helper()
+
+	enc, _, err := test.udp.encode(key, ptype, data)
 	if err != nil {
-		return test.errorf("packet (%d) encode error: %v", ptype, err)
+		test.t.Errorf("packet (%d) encode error: %v", ptype, err)
 	}
 	test.sent = append(test.sent, enc)
 	if err = test.udp.handlePacket(addr, enc); err != wantError {
-		return test.errorf("error mismatch: got %q, want %q", err, wantError)
+		test.t.Errorf("error mismatch: got %q, want %q", err, wantError)
 	}
-	return nil
 }
 
 // waits for a packet to be sent by the transport.
-// validate should have type func(*udpTest, X) error, where X is a packet type.
-func (test *udpTest) waitPacketOut(validate interface{}) (*net.UDPAddr, []byte, error) {
-	dgram := test.pipe.waitPacketOut()
-	p, _, hash, err := decodePacket(dgram.data)
+// validate should have type func(X, *net.UDPAddr, []byte), where X is a packet type.
+func (test *udpTest) waitPacketOut(validate interface{}) (closed bool) {
+	test.t.Helper()
+
+	dgram, ok := test.pipe.receive()
+	if !ok {
+		return true
+	}
+	p, _, hash, err := decodeV4(dgram.data)
 	if err != nil {
-		return &dgram.to, hash, test.errorf("sent packet decode error: %v", err)
+		test.t.Errorf("sent packet decode error: %v", err)
+		return false
 	}
 	fn := reflect.ValueOf(validate)
 	exptype := fn.Type().In(0)
-	if reflect.TypeOf(p) != exptype {
-		return &dgram.to, hash, test.errorf("sent packet type mismatch, got: %v, want: %v", reflect.TypeOf(p), exptype)
+	if !reflect.TypeOf(p).AssignableTo(exptype) {
+		test.t.Errorf("sent packet type mismatch, got: %v, want: %v", reflect.TypeOf(p), exptype)
+		return false
 	}
-	fn.Call([]reflect.Value{reflect.ValueOf(p)})
-	return &dgram.to, hash, nil
+	fn.Call([]reflect.Value{reflect.ValueOf(p), reflect.ValueOf(&dgram.to), reflect.ValueOf(hash)})
+	return false
 }
 
-func (test *udpTest) errorf(format string, args ...interface{}) error {
-	_, file, line, ok := runtime.Caller(2) // errorf + waitPacketOut
-	if ok {
-		file = filepath.Base(file)
-	} else {
-		file = "???"
-		line = 1
-	}
-	err := fmt.Errorf(format, args...)
-	fmt.Printf("\t%s:%d: %v\n", file, line, err)
-	test.t.Fail()
-	return err
-}
-
-func TestUDP_packetErrors(t *testing.T) {
+func TestUDPv4_packetErrors(t *testing.T) {
 	test := newUDPTest(t)
 	defer test.close()
 
-	test.packetIn(errExpired, pingPacket, &ping{From: testRemote, To: testLocalAnnounced, Version: 4})
-	test.packetIn(errUnsolicitedReply, pongPacket, &pong{ReplyTok: []byte{}, Expiration: futureExp})
-	test.packetIn(errUnknownNode, findnodePacket, &findnode{Expiration: futureExp})
-	test.packetIn(errUnsolicitedReply, neighborsPacket, &neighbors{Expiration: futureExp})
+	test.packetIn(errExpired, p_pingV4, &pingV4{From: testRemote, To: testLocalAnnounced, Version: 4})
+	test.packetIn(errUnsolicitedReply, p_pongV4, &pongV4{ReplyTok: []byte{}, Expiration: futureExp})
+	test.packetIn(errUnknownNode, p_findnodeV4, &findnodeV4{Expiration: futureExp})
+	test.packetIn(errUnsolicitedReply, p_neighborsV4, &neighborsV4{Expiration: futureExp})
 }
 
-func TestUDP_pingTimeout(t *testing.T) {
+func TestUDPv4_pingTimeout(t *testing.T) {
 	t.Parallel()
 	test := newUDPTest(t)
 	defer test.close()
 
+	key := newkey()
 	toaddr := &net.UDPAddr{IP: net.ParseIP("1.2.3.4"), Port: 2222}
-	toid := enode.ID{1, 2, 3, 4}
-	if err := test.udp.ping(toid, toaddr); err != errTimeout {
+	node := enode.NewV4(&key.PublicKey, toaddr.IP, 0, toaddr.Port)
+	if err := test.udp.ping(node); err != errTimeout {
 		t.Error("expected timeout error, got", err)
 	}
 }
 
-func TestUDP_responseTimeouts(t *testing.T) {
+func TestUDPv4_responseTimeouts(t *testing.T) {
 	t.Parallel()
 	test := newUDPTest(t)
 	defer test.close()
@@ -229,7 +230,7 @@ func TestUDP_responseTimeouts(t *testing.T) {
 	}
 }
 
-func TestUDP_findnodeTimeout(t *testing.T) {
+func TestUDPv4_findnodeTimeout(t *testing.T) {
 	t.Parallel()
 	test := newUDPTest(t)
 	defer test.close()
@@ -246,7 +247,7 @@ func TestUDP_findnodeTimeout(t *testing.T) {
 	}
 }
 
-func TestUDP_findnode(t *testing.T) {
+func TestUDPv4_findnode(t *testing.T) {
 	test := newUDPTest(t)
 	defer test.close()
 
@@ -275,10 +276,10 @@ func TestUDP_findnode(t *testing.T) {
 	test.table.db.UpdateLastPongReceived(remoteID, test.remoteaddr.IP, time.Now())
 
 	// check that closest neighbors are returned.
-	expected := test.table.closest(testTarget.id(), bucketSize)
-	test.packetIn(nil, findnodePacket, &findnode{Target: testTarget, Expiration: futureExp})
+	expected := test.table.closest(testTarget.id(), bucketSize, true)
+	test.packetIn(nil, p_findnodeV4, &findnodeV4{Target: testTarget, Expiration: futureExp})
 	waitNeighbors := func(want []*node) {
-		test.waitPacketOut(func(p *neighbors) {
+		test.waitPacketOut(func(p *neighborsV4, to *net.UDPAddr, hash []byte) {
 			if len(p.Nodes) != len(want) {
 				t.Errorf("wrong number of results: got %d, want %d", len(p.Nodes), bucketSize)
 			}
@@ -301,7 +302,7 @@ func TestUDP_findnode(t *testing.T) {
 	waitNeighbors(want)
 }
 
-func TestUDP_findnodeMultiReply(t *testing.T) {
+func TestUDPv4_findnodeMultiReply(t *testing.T) {
 	test := newUDPTest(t)
 	defer test.close()
 
@@ -322,7 +323,7 @@ func TestUDP_findnodeMultiReply(t *testing.T) {
 
 	// wait for the findnode to be sent.
 	// after it is sent, the transport is waiting for a reply
-	test.waitPacketOut(func(p *findnode) {
+	test.waitPacketOut(func(p *findnodeV4, to *net.UDPAddr, hash []byte) {
 		if p.Target != testTarget {
 			t.Errorf("wrong target: got %v, want %v", p.Target, testTarget)
 		}
@@ -339,8 +340,8 @@ func TestUDP_findnodeMultiReply(t *testing.T) {
 	for i := range list {
 		rpclist[i] = nodeToRPC(list[i])
 	}
-	test.packetIn(nil, neighborsPacket, &neighbors{Expiration: futureExp, Nodes: rpclist[:2]})
-	test.packetIn(nil, neighborsPacket, &neighbors{Expiration: futureExp, Nodes: rpclist[2:]})
+	test.packetIn(nil, p_neighborsV4, &neighborsV4{Expiration: futureExp, Nodes: rpclist[:2]})
+	test.packetIn(nil, p_neighborsV4, &neighborsV4{Expiration: futureExp, Nodes: rpclist[2:]})
 
 	// check that the sent neighbors are all returned by findnode
 	select {
@@ -356,46 +357,47 @@ func TestUDP_findnodeMultiReply(t *testing.T) {
 	}
 }
 
-func TestUDP_pingMatch(t *testing.T) {
+func TestUDPv4_pingMatch(t *testing.T) {
 	test := newUDPTest(t)
 	defer test.close()
 
 	randToken := make([]byte, 32)
 	crand.Read(randToken)
 
-	test.packetIn(nil, pingPacket, &ping{From: testRemote, To: testLocalAnnounced, Version: 4, Expiration: futureExp})
-	test.waitPacketOut(func(*pong) error { return nil })
-	test.waitPacketOut(func(*ping) error { return nil })
-	test.packetIn(errUnsolicitedReply, pongPacket, &pong{ReplyTok: randToken, To: testLocalAnnounced, Expiration: futureExp})
+	test.packetIn(nil, p_pingV4, &pingV4{From: testRemote, To: testLocalAnnounced, Version: 4, Expiration: futureExp})
+	test.waitPacketOut(func(*pongV4, *net.UDPAddr, []byte) {})
+	test.waitPacketOut(func(*pingV4, *net.UDPAddr, []byte) {})
+	test.packetIn(errUnsolicitedReply, p_pongV4, &pongV4{ReplyTok: randToken, To: testLocalAnnounced, Expiration: futureExp})
 }
 
-func TestUDP_pingMatchIP(t *testing.T) {
+func TestUDPv4_pingMatchIP(t *testing.T) {
 	test := newUDPTest(t)
 	defer test.close()
 
-	test.packetIn(nil, pingPacket, &ping{From: testRemote, To: testLocalAnnounced, Version: 4, Expiration: futureExp})
-	test.waitPacketOut(func(*pong) error { return nil })
+	test.packetIn(nil, p_pingV4, &pingV4{From: testRemote, To: testLocalAnnounced, Version: 4, Expiration: futureExp})
+	test.waitPacketOut(func(*pongV4, *net.UDPAddr, []byte) {})
 
-	_, hash, _ := test.waitPacketOut(func(*ping) error { return nil })
-	wrongAddr := &net.UDPAddr{IP: net.IP{33, 44, 1, 2}, Port: 30000}
-	test.packetInFrom(errUnsolicitedReply, test.remotekey, wrongAddr, pongPacket, &pong{
-		ReplyTok:   hash,
-		To:         testLocalAnnounced,
-		Expiration: futureExp,
+	test.waitPacketOut(func(p *pingV4, to *net.UDPAddr, hash []byte) {
+		wrongAddr := &net.UDPAddr{IP: net.IP{33, 44, 1, 2}, Port: 30000}
+		test.packetInFrom(errUnsolicitedReply, test.remotekey, wrongAddr, p_pongV4, &pongV4{
+			ReplyTok:   hash,
+			To:         testLocalAnnounced,
+			Expiration: futureExp,
+		})
 	})
 }
 
-func TestUDP_successfulPing(t *testing.T) {
+func TestUDPv4_successfulPing(t *testing.T) {
 	test := newUDPTest(t)
 	added := make(chan *node, 1)
 	test.table.nodeAddedHook = func(n *node) { added <- n }
 	defer test.close()
 
 	// The remote side sends a ping packet to initiate the exchange.
-	go test.packetIn(nil, pingPacket, &ping{From: testRemote, To: testLocalAnnounced, Version: 4, Expiration: futureExp})
+	go test.packetIn(nil, p_pingV4, &pingV4{From: testRemote, To: testLocalAnnounced, Version: 4, Expiration: futureExp})
 
 	// the ping is replied to.
-	test.waitPacketOut(func(p *pong) {
+	test.waitPacketOut(func(p *pongV4, to *net.UDPAddr, hash []byte) {
 		pinghash := test.sent[0][:macSize]
 		if !bytes.Equal(p.ReplyTok, pinghash) {
 			t.Errorf("got pong.ReplyTok %x, want %x", p.ReplyTok, pinghash)
@@ -412,7 +414,7 @@ func TestUDP_successfulPing(t *testing.T) {
 	})
 
 	// remote is unknown, the table pings back.
-	_, hash, _ := test.waitPacketOut(func(p *ping) error {
+	test.waitPacketOut(func(p *pingV4, to *net.UDPAddr, hash []byte) {
 		if !reflect.DeepEqual(p.From, test.udp.ourEndpoint()) {
 			t.Errorf("got ping.From %#v, want %#v", p.From, test.udp.ourEndpoint())
 		}
@@ -425,9 +427,8 @@ func TestUDP_successfulPing(t *testing.T) {
 		if !reflect.DeepEqual(p.To, wantTo) {
 			t.Errorf("got ping.To %v, want %v", p.To, wantTo)
 		}
-		return nil
+		test.packetIn(nil, p_pongV4, &pongV4{ReplyTok: hash, Expiration: futureExp})
 	})
-	test.packetIn(nil, pongPacket, &pong{ReplyTok: hash, Expiration: futureExp})
 
 	// the node should be added to the table shortly after getting the
 	// pong packet.
@@ -457,7 +458,7 @@ var testPackets = []struct {
 }{
 	{
 		input: "71dbda3a79554728d4f94411e42ee1f8b0d561c10e1e5f5893367948c6a7d70bb87b235fa28a77070271b6c164a2dce8c7e13a5739b53b5e96f2e5acb0e458a02902f5965d55ecbeb2ebb6cabb8b2b232896a36b737666c55265ad0a68412f250001ea04cb847f000001820cfa8215a8d790000000000000000000000000000000018208ae820d058443b9a355",
-		wantPacket: &ping{
+		wantPacket: &pingV4{
 			Version:    4,
 			From:       rpcEndpoint{net.ParseIP("127.0.0.1").To4(), 3322, 5544},
 			To:         rpcEndpoint{net.ParseIP("::1"), 2222, 3333},
@@ -467,7 +468,7 @@ var testPackets = []struct {
 	},
 	{
 		input: "e9614ccfd9fc3e74360018522d30e1419a143407ffcce748de3e22116b7e8dc92ff74788c0b6663aaa3d67d641936511c8f8d6ad8698b820a7cf9e1be7155e9a241f556658c55428ec0563514365799a4be2be5a685a80971ddcfa80cb422cdd0101ec04cb847f000001820cfa8215a8d790000000000000000000000000000000018208ae820d058443b9a3550102",
-		wantPacket: &ping{
+		wantPacket: &pingV4{
 			Version:    4,
 			From:       rpcEndpoint{net.ParseIP("127.0.0.1").To4(), 3322, 5544},
 			To:         rpcEndpoint{net.ParseIP("::1"), 2222, 3333},
@@ -477,7 +478,7 @@ var testPackets = []struct {
 	},
 	{
 		input: "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",
-		wantPacket: &ping{
+		wantPacket: &pingV4{
 			Version:    555,
 			From:       rpcEndpoint{net.ParseIP("2001:db8:3c4d:15::abcd:ef12"), 3322, 5544},
 			To:         rpcEndpoint{net.ParseIP("2001:db8:85a3:8d3:1319:8a2e:370:7348"), 2222, 33338},
@@ -487,7 +488,7 @@ var testPackets = []struct {
 	},
 	{
 		input: "09b2428d83348d27cdf7064ad9024f526cebc19e4958f0fdad87c15eb598dd61d08423e0bf66b2069869e1724125f820d851c136684082774f870e614d95a2855d000f05d1648b2d5945470bc187c2d2216fbe870f43ed0909009882e176a46b0102f846d79020010db885a308d313198a2e037073488208ae82823aa0fbc914b16819237dcd8801d7e53f69e9719adecb3cc0e790c57e91ca4461c9548443b9a355c6010203c2040506a0c969a58f6f9095004c0177a6b47f451530cab38966a25cca5cb58f055542124e",
-		wantPacket: &pong{
+		wantPacket: &pongV4{
 			To:         rpcEndpoint{net.ParseIP("2001:db8:85a3:8d3:1319:8a2e:370:7348"), 2222, 33338},
 			ReplyTok:   common.Hex2Bytes("fbc914b16819237dcd8801d7e53f69e9719adecb3cc0e790c57e91ca4461c954"),
 			Expiration: 1136239445,
@@ -496,7 +497,7 @@ var testPackets = []struct {
 	},
 	{
 		input: "c7c44041b9f7c7e41934417ebac9a8e1a4c6298f74553f2fcfdcae6ed6fe53163eb3d2b52e39fe91831b8a927bf4fc222c3902202027e5e9eb812195f95d20061ef5cd31d502e47ecb61183f74a504fe04c51e73df81f25c4d506b26db4517490103f84eb840ca634cae0d49acb401d8a4c6b6fe8c55b70d115bf400769cc1400f3258cd31387574077f301b421bc84df7266c44e9e6d569fc56be00812904767bf5ccd1fc7f8443b9a35582999983999999280dc62cc8255c73471e0a61da0c89acdc0e035e260add7fc0c04ad9ebf3919644c91cb247affc82b69bd2ca235c71eab8e49737c937a2c396",
-		wantPacket: &findnode{
+		wantPacket: &findnodeV4{
 			Target:     hexEncPubkey("ca634cae0d49acb401d8a4c6b6fe8c55b70d115bf400769cc1400f3258cd31387574077f301b421bc84df7266c44e9e6d569fc56be00812904767bf5ccd1fc7f"),
 			Expiration: 1136239445,
 			Rest:       []rlp.RawValue{{0x82, 0x99, 0x99}, {0x83, 0x99, 0x99, 0x99}},
@@ -504,7 +505,7 @@ var testPackets = []struct {
 	},
 	{
 		input: "c679fc8fe0b8b12f06577f2e802d34f6fa257e6137a995f6f4cbfc9ee50ed3710faf6e66f932c4c8d81d64343f429651328758b47d3dbc02c4042f0fff6946a50f4a49037a72bb550f3a7872363a83e1b9ee6469856c24eb4ef80b7535bcf99c0004f9015bf90150f84d846321163782115c82115db8403155e1427f85f10a5c9a7755877748041af1bcd8d474ec065eb33df57a97babf54bfd2103575fa829115d224c523596b401065a97f74010610fce76382c0bf32f84984010203040101b840312c55512422cf9b8a4097e9a6ad79402e87a15ae909a4bfefa22398f03d20951933beea1e4dfa6f968212385e829f04c2d314fc2d4e255e0d3bc08792b069dbf8599020010db83c4d001500000000abcdef12820d05820d05b84038643200b172dcfef857492156971f0e6aa2c538d8b74010f8e140811d53b98c765dd2d96126051913f44582e8c199ad7c6d6819e9a56483f637feaac9448aacf8599020010db885a308d313198a2e037073488203e78203e8b8408dcab8618c3253b558d459da53bd8fa68935a719aff8b811197101a4b2b47dd2d47295286fc00cc081bb542d760717d1bdd6bec2c37cd72eca367d6dd3b9df738443b9a355010203b525a138aa34383fec3d2719a0",
-		wantPacket: &neighbors{
+		wantPacket: &neighborsV4{
 			Nodes: []rpcNode{
 				{
 					ID:  hexEncPubkey("3155e1427f85f10a5c9a7755877748041af1bcd8d474ec065eb33df57a97babf54bfd2103575fa829115d224c523596b401065a97f74010610fce76382c0bf32"),
@@ -537,7 +538,7 @@ var testPackets = []struct {
 	},
 }
 
-func TestForwardCompatibility(t *testing.T) {
+func TestUDPv4_forwardCompatibility(t *testing.T) {
 	testkey, _ := crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
 	wantNodeKey := encodePubkey(&testkey.PublicKey)
 
@@ -546,7 +547,7 @@ func TestForwardCompatibility(t *testing.T) {
 		if err != nil {
 			t.Fatalf("invalid hex: %s", test.input)
 		}
-		packet, nodekey, _, err := decodePacket(input)
+		packet, nodekey, _, err := decodeV4(input)
 		if err != nil {
 			t.Errorf("did not accept packet %s\n%v", test.input, err)
 			continue
@@ -610,6 +611,7 @@ func (c *dgramPipe) Close() error {
 		close(c.closing)
 		c.closed = true
 	}
+	c.cond.Broadcast()
 	return nil
 }
 
@@ -617,14 +619,17 @@ func (c *dgramPipe) LocalAddr() net.Addr {
 	return &net.UDPAddr{IP: testLocal.IP, Port: int(testLocal.UDP)}
 }
 
-func (c *dgramPipe) waitPacketOut() dgram {
+func (c *dgramPipe) receive() (dgram, bool) {
 	c.mu.Lock()
 	defer c.mu.Unlock()
-	for len(c.queue) == 0 {
+	for len(c.queue) == 0 && !c.closed {
 		c.cond.Wait()
 	}
+	if c.closed {
+		return dgram{}, false
+	}
 	p := c.queue[0]
 	copy(c.queue, c.queue[1:])
 	c.queue = c.queue[:len(c.queue)-1]
-	return p
+	return p, true
 }