diff --git a/p2p/discover/table.go b/p2p/discover/table.go
index 61c62f1878e4ab20bb104bdad69292eac737a409..3460e8377cfee48319b27f49ba4d02c4d34405d4 100644
--- a/p2p/discover/table.go
+++ b/p2p/discover/table.go
@@ -53,15 +53,17 @@ const (
bucketIPLimit, bucketSubnet = 2, 24 // at most 2 addresses from the same /24
tableIPLimit, tableSubnet = 10, 24
- maxFindnodeFailures = 5 // Nodes exceeding this limit are dropped
- refreshInterval = 30 * time.Minute
- revalidateInterval = 10 * time.Second
- copyNodesInterval = 30 * time.Second
- seedMinTableTime = 5 * time.Minute
- seedCount = 30
- seedMaxAge = 5 * 24 * time.Hour
+ refreshInterval = 30 * time.Minute
+ revalidateInterval = 10 * time.Second
+ copyNodesInterval = 30 * time.Second
+ seedMinTableTime = 5 * time.Minute
+ seedCount = 30
+ seedMaxAge = 5 * 24 * time.Hour
)
+// Table is the 'node table', a Kademlia-like index of neighbor nodes. The table keeps
+// itself up-to-date by verifying the liveness of neighbors and requesting their node
+// records when announcements of a new record version are received.
type Table struct {
mutex sync.Mutex // protects buckets, bucket content, nursery, rand
buckets [nBuckets]*bucket // index of known nodes by distance
@@ -80,12 +82,13 @@ type Table struct {
nodeAddedHook func(*node) // for testing
}
-// transport is implemented by UDP transports.
+// transport is implemented by the UDP transports.
type transport interface {
Self() *enode.Node
lookupRandom() []*enode.Node
lookupSelf() []*enode.Node
- ping(*enode.Node) error
+ ping(*enode.Node) (seq uint64, err error)
+ requestENR(*enode.Node) (*enode.Node, error)
}
// bucket contains nodes, ordered by their last activity. the entry
@@ -175,14 +178,16 @@ func (tab *Table) ReadRandomNodes(buf []*enode.Node) (n int) {
return i + 1
}
-// 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 {
+// getNode returns the node with the given ID or nil if it isn't in the table.
+func (tab *Table) getNode(id enode.ID) *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])
+ defer tab.mutex.Unlock()
+
+ b := tab.bucket(id)
+ for _, e := range b.entries {
+ if e.ID() == id {
+ return unwrapNode(e)
+ }
}
return nil
}
@@ -226,7 +231,7 @@ func (tab *Table) refresh() <-chan struct{} {
return done
}
-// loop schedules refresh, revalidate runs and coordinates shutdown.
+// loop schedules runs of doRefresh, doRevalidate and copyLiveNodes.
func (tab *Table) loop() {
var (
revalidate = time.NewTimer(tab.nextRevalidateTime())
@@ -288,9 +293,8 @@ loop:
close(tab.closed)
}
-// doRefresh performs a lookup for a random target to keep buckets
-// full. seed nodes are inserted if the table is empty (initial
-// bootstrap or discarded faulty peers).
+// doRefresh performs a lookup for a random target to keep buckets full. seed nodes are
+// inserted if the table is empty (initial bootstrap or discarded faulty peers).
func (tab *Table) doRefresh(done chan struct{}) {
defer close(done)
@@ -324,8 +328,8 @@ func (tab *Table) loadSeedNodes() {
}
}
-// doRevalidate checks that the last node in a random bucket is still live
-// and replaces or deletes the node if it isn't.
+// doRevalidate checks that the last node in a random bucket is still live and replaces or
+// deletes the node if it isn't.
func (tab *Table) doRevalidate(done chan<- struct{}) {
defer func() { done <- struct{}{} }()
@@ -336,7 +340,17 @@ func (tab *Table) doRevalidate(done chan<- struct{}) {
}
// Ping the selected node and wait for a pong.
- err := tab.net.ping(unwrapNode(last))
+ remoteSeq, err := tab.net.ping(unwrapNode(last))
+
+ // Also fetch record if the node replied and returned a higher sequence number.
+ if last.Seq() < remoteSeq {
+ n, err := tab.net.requestENR(unwrapNode(last))
+ if err != nil {
+ tab.log.Debug("ENR request failed", "id", last.ID(), "addr", last.addr(), "err", err)
+ } else {
+ last = &node{Node: *n, addedAt: last.addedAt, livenessChecks: last.livenessChecks}
+ }
+ }
tab.mutex.Lock()
defer tab.mutex.Unlock()
diff --git a/p2p/discover/table_test.go b/p2p/discover/table_test.go
index 81763e7fead16e078bb43a9835ec556f8c25f7e1..895c284b270b38f9779e213c6b6191fdaa575aee 100644
--- a/p2p/discover/table_test.go
+++ b/p2p/discover/table_test.go
@@ -368,6 +368,34 @@ func TestTable_addSeenNode(t *testing.T) {
checkIPLimitInvariant(t, tab)
}
+// This test checks that ENR updates happen during revalidation. If a node in the table
+// announces a new sequence number, the new record should be pulled.
+func TestTable_revalidateSyncRecord(t *testing.T) {
+ transport := newPingRecorder()
+ tab, db := newTestTable(transport)
+ <-tab.initDone
+ defer db.Close()
+ defer tab.close()
+
+ // Insert a node.
+ var r enr.Record
+ r.Set(enr.IP(net.IP{127, 0, 0, 1}))
+ id := enode.ID{1}
+ n1 := wrapNode(enode.SignNull(&r, id))
+ tab.addSeenNode(n1)
+
+ // Update the node record.
+ r.Set(enr.WithEntry("foo", "bar"))
+ n2 := enode.SignNull(&r, id)
+ transport.updateRecord(n2)
+
+ tab.doRevalidate(make(chan struct{}, 1))
+ intable := tab.getNode(id)
+ if !reflect.DeepEqual(intable, n2) {
+ t.Fatalf("table contains old record with seq %d, want seq %d", intable.Seq(), n2.Seq())
+ }
+}
+
// 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{} {
diff --git a/p2p/discover/table_util_test.go b/p2p/discover/table_util_test.go
index 71cb1895b0a37f58298d126503023ce71425e227..3075c43408f5a7f378c387e95f6f9952f123d6c0 100644
--- a/p2p/discover/table_util_test.go
+++ b/p2p/discover/table_util_test.go
@@ -98,6 +98,7 @@ func fillTable(tab *Table, nodes []*node) {
type pingRecorder struct {
mu sync.Mutex
dead, pinged map[enode.ID]bool
+ records map[enode.ID]*enode.Node
n *enode.Node
}
@@ -107,38 +108,53 @@ func newPingRecorder() *pingRecorder {
n := enode.SignNull(&r, enode.ID{})
return &pingRecorder{
- dead: make(map[enode.ID]bool),
- pinged: make(map[enode.ID]bool),
- n: n,
+ dead: make(map[enode.ID]bool),
+ pinged: make(map[enode.ID]bool),
+ records: make(map[enode.ID]*enode.Node),
+ n: n,
}
}
-func (t *pingRecorder) Self() *enode.Node {
- return nullNode
+// setRecord updates a node record. Future calls to ping and
+// requestENR will return this record.
+func (t *pingRecorder) updateRecord(n *enode.Node) {
+ t.mu.Lock()
+ defer t.mu.Unlock()
+ t.records[n.ID()] = n
}
-func (t *pingRecorder) ping(n *enode.Node) error {
+// Stubs to satisfy the transport interface.
+func (t *pingRecorder) Self() *enode.Node { return nullNode }
+func (t *pingRecorder) lookupSelf() []*enode.Node { return nil }
+func (t *pingRecorder) lookupRandom() []*enode.Node { return nil }
+func (t *pingRecorder) close() {}
+
+// ping simulates a ping request.
+func (t *pingRecorder) ping(n *enode.Node) (seq uint64, err error) {
t.mu.Lock()
defer t.mu.Unlock()
t.pinged[n.ID()] = true
if t.dead[n.ID()] {
- return errTimeout
- } else {
- return nil
+ return 0, errTimeout
}
+ if t.records[n.ID()] != nil {
+ seq = t.records[n.ID()].Seq()
+ }
+ return seq, nil
}
-func (t *pingRecorder) lookupSelf() []*enode.Node {
- return nil
-}
+// requestENR simulates an ENR request.
+func (t *pingRecorder) requestENR(n *enode.Node) (*enode.Node, error) {
+ t.mu.Lock()
+ defer t.mu.Unlock()
-func (t *pingRecorder) lookupRandom() []*enode.Node {
- return nil
+ if t.dead[n.ID()] || t.records[n.ID()] == nil {
+ return nil, errTimeout
+ }
+ return t.records[n.ID()], nil
}
-func (t *pingRecorder) close() {}
-
func hasDuplicates(slice []*node) bool {
seen := make(map[enode.ID]bool)
for i, e := range slice {
diff --git a/p2p/discover/v4_udp.go b/p2p/discover/v4_udp.go
index 3c68beac1c858027ba0efc45d079d1fd4a1f2d48..b0b0053a7a07668d3d2a7ec87cc3a50cb709a14a 100644
--- a/p2p/discover/v4_udp.go
+++ b/p2p/discover/v4_udp.go
@@ -31,6 +31,7 @@ import (
"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"
"github.com/ethereum/go-ethereum/p2p/netutil"
"github.com/ethereum/go-ethereum/rlp"
)
@@ -47,12 +48,12 @@ var (
errClosed = errors.New("socket closed")
)
-// Timeouts
const (
respTimeout = 500 * time.Millisecond
expiration = 20 * time.Second
bondExpiration = 24 * time.Hour
+ maxFindnodeFailures = 5 // nodes exceeding this limit are dropped
ntpFailureThreshold = 32 // Continuous timeouts after which to check NTP
ntpWarningCooldown = 10 * time.Minute // Minimum amount of time to pass before repeating NTP warning
driftThreshold = 10 * time.Second // Allowed clock drift before warning user
@@ -69,6 +70,8 @@ const (
p_pongV4
p_findnodeV4
p_neighborsV4
+ p_enrRequestV4
+ p_enrResponseV4
)
// RPC request structures
@@ -112,6 +115,21 @@ type (
Rest []rlp.RawValue `rlp:"tail"`
}
+ // enrRequestV4 queries for the remote node's record.
+ enrRequestV4 struct {
+ Expiration uint64
+ // Ignore additional fields (for forward compatibility).
+ Rest []rlp.RawValue `rlp:"tail"`
+ }
+
+ // enrResponseV4 is the reply to enrRequestV4.
+ enrResponseV4 struct {
+ ReplyTok []byte // Hash of the enrRequest packet.
+ Record enr.Record
+ // Ignore additional fields (for forward compatibility).
+ Rest []rlp.RawValue `rlp:"tail"`
+ }
+
rpcNode struct {
IP net.IP // len 4 for IPv4 or 16 for IPv6
UDP uint16 // for discovery protocol
@@ -126,14 +144,15 @@ type (
}
)
-// packet is implemented by all v4 protocol messages.
+// packetV4 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.
+ // packet name and type for logging purposes.
name() string
+ kind() byte
}
func makeEndpoint(addr *net.UDPAddr, tcpPort uint16) rpcEndpoint {
@@ -191,7 +210,7 @@ type UDPv4 struct {
closing chan struct{}
}
-// pending represents a pending reply.
+// replyMatcher represents a pending reply.
//
// Some implementations of the protocol wish to send more than one
// reply packet to findnode. In general, any neighbors packet cannot
@@ -217,17 +236,20 @@ type replyMatcher struct {
// errc receives nil when the callback indicates completion or an
// error if no further reply is received within the timeout.
- errc chan<- error
+ errc chan error
+
+ // reply contains the most recent reply. This field is safe for reading after errc has
+ // received a value.
+ reply packetV4
}
type replyMatchFunc func(interface{}) (matched bool, requestDone bool)
+// reply is a reply packet from a certain node.
type reply struct {
- from enode.ID
- ip net.IP
- ptype byte
- data packetV4
-
+ from enode.ID
+ ip net.IP
+ data packetV4
// loop indicates whether there was
// a matching request by sending on this channel.
matched chan<- bool
@@ -377,7 +399,8 @@ func (t *UDPv4) lookupWorker(n *node, targetKey encPubkey, reply chan<- []*node)
t.tab.delete(n)
}
} else if fails > 0 {
- t.db.UpdateFindFails(n.ID(), n.IP(), fails-1)
+ // Reset failure counter because it counts _consecutive_ failures.
+ t.db.UpdateFindFails(n.ID(), n.IP(), 0)
}
// Grab as many nodes as possible. Some of them might not be alive anymore, but we'll
@@ -388,23 +411,34 @@ func (t *UDPv4) lookupWorker(n *node, targetKey encPubkey, reply chan<- []*node)
reply <- r
}
-// Resolve searches for a specific node with the given ID.
-// It returns nil if the node could not be found.
+// Resolve searches for a specific node with the given ID and tries to get the most recent
+// version of the node record for it. It returns n if the node could not be resolved.
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
+ // Try asking directly. This works if the node is still responding on the endpoint we have.
+ if rn, err := t.requestENR(n); err == nil {
+ return rn
+ }
+ // Check table for the ID, we might have a newer version there.
+ if intable := t.tab.getNode(n.ID()); intable != nil && intable.Seq() > n.Seq() {
+ n = intable
+ if rn, err := t.requestENR(n); err == nil {
+ return rn
}
}
- return nil
+ // Otherwise perform a network lookup.
+ var key *enode.Secp256k1
+ if n.Load(key) != nil {
+ return n // no secp256k1 key
+ }
+ result := t.LookupPubkey((*ecdsa.PublicKey)(key))
+ for _, rn := range result {
+ if rn.ID() == n.ID() {
+ if rn, err := t.requestENR(rn); err == nil {
+ return rn
+ }
+ }
+ }
+ return n
}
func (t *UDPv4) ourEndpoint() rpcEndpoint {
@@ -414,28 +448,27 @@ func (t *UDPv4) ourEndpoint() rpcEndpoint {
}
// ping sends a ping message to the given node and waits for a reply.
-func (t *UDPv4) ping(n *enode.Node) error {
- return <-t.sendPing(n.ID(), &net.UDPAddr{IP: n.IP(), Port: n.UDP()}, nil)
+func (t *UDPv4) ping(n *enode.Node) (seq uint64, err error) {
+ rm := t.sendPing(n.ID(), &net.UDPAddr{IP: n.IP(), Port: n.UDP()}, nil)
+ if err = <-rm.errc; err == nil {
+ seq = seqFromTail(rm.reply.(*pongV4).Rest)
+ }
+ return seq, err
}
// sendPing sends a ping message to the given node and invokes the callback
// when the reply arrives.
-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 := t.encode(t.priv, p_pingV4, req)
+func (t *UDPv4) sendPing(toid enode.ID, toaddr *net.UDPAddr, callback func()) *replyMatcher {
+ req := t.makePing(toaddr)
+ packet, hash, err := t.encode(t.priv, req)
if err != nil {
errc := make(chan error, 1)
errc <- err
- return errc
+ return &replyMatcher{errc: errc}
}
// 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, p_pongV4, func(p interface{}) (matched bool, requestDone bool) {
+ rm := 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()
@@ -445,25 +478,30 @@ func (t *UDPv4) sendPing(toid enode.ID, toaddr *net.UDPAddr, callback func()) <-
// Send the packet.
t.localNode.UDPContact(toaddr)
t.write(toaddr, toid, req.name(), packet)
- return errc
+ return rm
+}
+
+func (t *UDPv4) makePing(toaddr *net.UDPAddr) *pingV4 {
+ seq, _ := rlp.EncodeToBytes(t.localNode.Node().Seq())
+ return &pingV4{
+ Version: 4,
+ From: t.ourEndpoint(),
+ To: makeEndpoint(toaddr, 0),
+ Expiration: uint64(time.Now().Add(expiration).Unix()),
+ Rest: []rlp.RawValue{seq},
+ }
}
// findnode sends a findnode request to the given node and waits until
// the node has sent up to k neighbors.
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.sendPing(toid, toaddr, nil)
- // Wait for them to ping back and process our pong.
- time.Sleep(respTimeout)
- }
+ t.ensureBond(toid, toaddr)
// Add a matcher for 'neighbours' replies to the pending reply queue. The matcher is
// active until enough nodes have been received.
nodes := make([]*node, 0, bucketSize)
nreceived := 0
- errc := t.pending(toid, toaddr.IP, p_neighborsV4, func(r interface{}) (matched bool, requestDone bool) {
+ rm := t.pending(toid, toaddr.IP, p_neighborsV4, func(r interface{}) (matched bool, requestDone bool) {
reply := r.(*neighborsV4)
for _, rn := range reply.Nodes {
nreceived++
@@ -476,16 +514,56 @@ func (t *UDPv4) findnode(toid enode.ID, toaddr *net.UDPAddr, target encPubkey) (
}
return true, nreceived >= bucketSize
})
- t.send(toaddr, toid, p_findnodeV4, &findnodeV4{
+ t.send(toaddr, toid, &findnodeV4{
Target: target,
Expiration: uint64(time.Now().Add(expiration).Unix()),
})
- return nodes, <-errc
+ return nodes, <-rm.errc
+}
+
+// requestENR sends enrRequest to the given node and waits for a response.
+func (t *UDPv4) requestENR(n *enode.Node) (*enode.Node, error) {
+ addr := &net.UDPAddr{IP: n.IP(), Port: n.UDP()}
+ t.ensureBond(n.ID(), addr)
+
+ req := &enrRequestV4{
+ Expiration: uint64(time.Now().Add(expiration).Unix()),
+ }
+ packet, hash, err := t.encode(t.priv, req)
+ if err != nil {
+ return nil, err
+ }
+ // Add a matcher for the reply to the pending reply queue. Responses are matched if
+ // they reference the request we're about to send.
+ rm := t.pending(n.ID(), addr.IP, p_enrResponseV4, func(r interface{}) (matched bool, requestDone bool) {
+ matched = bytes.Equal(r.(*enrResponseV4).ReplyTok, hash)
+ return matched, matched
+ })
+ // Send the packet and wait for the reply.
+ t.write(addr, n.ID(), req.name(), packet)
+ if err := <-rm.errc; err != nil {
+ return nil, err
+ }
+ // Verify the response record.
+ respN, err := enode.New(enode.ValidSchemes, &rm.reply.(*enrResponseV4).Record)
+ if err != nil {
+ return nil, err
+ }
+ if respN.ID() != n.ID() {
+ return nil, fmt.Errorf("invalid ID in response record")
+ }
+ if respN.Seq() < n.Seq() {
+ return n, nil // response record is older
+ }
+ if err := netutil.CheckRelayIP(addr.IP, respN.IP()); err != nil {
+ return nil, fmt.Errorf("invalid IP in response record: %v", err)
+ }
+ return respN, nil
}
// pending adds a reply matcher to the pending reply queue.
// see the documentation of type replyMatcher for a detailed explanation.
-func (t *UDPv4) 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) *replyMatcher {
ch := make(chan error, 1)
p := &replyMatcher{from: id, ip: ip, ptype: ptype, callback: callback, errc: ch}
select {
@@ -494,15 +572,15 @@ func (t *UDPv4) pending(id enode.ID, ip net.IP, ptype byte, callback replyMatchF
case <-t.closing:
ch <- errClosed
}
- return ch
+ return p
}
// handleReply dispatches a reply packet, invoking reply matchers. It returns
// whether any matcher considered the packet acceptable.
-func (t *UDPv4) handleReply(from enode.ID, fromIP net.IP, ptype byte, req packetV4) bool {
+func (t *UDPv4) handleReply(from enode.ID, fromIP net.IP, req packetV4) bool {
matched := make(chan bool, 1)
select {
- case t.gotreply <- reply{from, fromIP, ptype, req, matched}:
+ case t.gotreply <- reply{from, fromIP, req, matched}:
// loop will handle it
return <-matched
case <-t.closing:
@@ -565,11 +643,12 @@ func (t *UDPv4) loop() {
var matched bool // whether any replyMatcher considered the reply acceptable.
for el := plist.Front(); el != nil; el = el.Next() {
p := el.Value.(*replyMatcher)
- if p.from == r.from && p.ptype == r.ptype && p.ip.Equal(r.ip) {
+ if p.from == r.from && p.ptype == r.data.kind() && p.ip.Equal(r.ip) {
ok, requestDone := p.callback(r.data)
matched = matched || ok
// Remove the matcher if callback indicates that all replies have been received.
if requestDone {
+ p.reply = r.data
p.errc <- nil
plist.Remove(el)
}
@@ -635,8 +714,8 @@ func init() {
}
}
-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)
+func (t *UDPv4) send(toaddr *net.UDPAddr, toid enode.ID, req packetV4) ([]byte, error) {
+ packet, hash, err := t.encode(t.priv, req)
if err != nil {
return hash, err
}
@@ -649,18 +728,19 @@ func (t *UDPv4) write(toaddr *net.UDPAddr, toid enode.ID, what string, packet []
return err
}
-func (t *UDPv4) encode(priv *ecdsa.PrivateKey, ptype byte, req interface{}) (packet, hash []byte, err error) {
+func (t *UDPv4) encode(priv *ecdsa.PrivateKey, req packetV4) (packet, hash []byte, err error) {
+ name := req.name()
b := new(bytes.Buffer)
b.Write(headSpace)
- b.WriteByte(ptype)
+ b.WriteByte(req.kind())
if err := rlp.Encode(b, req); err != nil {
- t.log.Error("Can't encode discv4 packet", "err", err)
+ t.log.Error(fmt.Sprintf("Can't encode %s packet", name), "err", err)
return nil, nil, err
}
packet = b.Bytes()
sig, err := crypto.Sign(crypto.Keccak256(packet[headSize:]), priv)
if err != nil {
- t.log.Error("Can't sign discv4 packet", "err", err)
+ t.log.Error(fmt.Sprintf("Can't sign %s packet", name), "err", err)
return nil, nil, err
}
copy(packet[macSize:], sig)
@@ -743,6 +823,10 @@ func decodeV4(buf []byte) (packetV4, encPubkey, []byte, error) {
req = new(findnodeV4)
case p_neighborsV4:
req = new(neighborsV4)
+ case p_enrRequestV4:
+ req = new(enrRequestV4)
+ case p_enrResponseV4:
+ req = new(enrResponseV4)
default:
return nil, fromKey, hash, fmt.Errorf("unknown type: %d", ptype)
}
@@ -751,7 +835,41 @@ func decodeV4(buf []byte) (packetV4, encPubkey, []byte, error) {
return req, fromKey, hash, err
}
-// Packet Handlers
+// checkBond checks if the given node has a recent enough endpoint proof.
+func (t *UDPv4) checkBond(id enode.ID, ip net.IP) bool {
+ return time.Since(t.db.LastPongReceived(id, ip)) < bondExpiration
+}
+
+// ensureBond solicits a ping from a node if we haven't seen a ping from it for a while.
+// This ensures there is a valid endpoint proof on the remote end.
+func (t *UDPv4) ensureBond(toid enode.ID, toaddr *net.UDPAddr) {
+ tooOld := time.Since(t.db.LastPingReceived(toid, toaddr.IP)) > bondExpiration
+ if tooOld || t.db.FindFails(toid, toaddr.IP) > maxFindnodeFailures {
+ rm := t.sendPing(toid, toaddr, nil)
+ <-rm.errc
+ // Wait for them to ping back and process our pong.
+ time.Sleep(respTimeout)
+ }
+}
+
+// expired checks whether the given UNIX time stamp is in the past.
+func expired(ts uint64) bool {
+ return time.Unix(int64(ts), 0).Before(time.Now())
+}
+
+func seqFromTail(tail []rlp.RawValue) uint64 {
+ if len(tail) == 0 {
+ return 0
+ }
+ var seq uint64
+ rlp.DecodeBytes(tail[0], &seq)
+ return seq
+}
+
+// PING/v4
+
+func (req *pingV4) name() string { return "PING/v4" }
+func (req *pingV4) kind() byte { return p_pingV4 }
func (req *pingV4) preverify(t *UDPv4, from *net.UDPAddr, fromID enode.ID, fromKey encPubkey) error {
if expired(req.Expiration) {
@@ -767,10 +885,12 @@ func (req *pingV4) preverify(t *UDPv4, from *net.UDPAddr, fromID enode.ID, fromK
func (req *pingV4) handle(t *UDPv4, from *net.UDPAddr, fromID enode.ID, mac []byte) {
// Reply.
- t.send(from, fromID, p_pongV4, &pongV4{
+ seq, _ := rlp.EncodeToBytes(t.localNode.Node().Seq())
+ t.send(from, fromID, &pongV4{
To: makeEndpoint(from, req.From.TCP),
ReplyTok: mac,
Expiration: uint64(time.Now().Add(expiration).Unix()),
+ Rest: []rlp.RawValue{seq},
})
// Ping back if our last pong on file is too far in the past.
@@ -788,13 +908,16 @@ func (req *pingV4) handle(t *UDPv4, from *net.UDPAddr, fromID enode.ID, mac []by
t.localNode.UDPEndpointStatement(from, &net.UDPAddr{IP: req.To.IP, Port: int(req.To.UDP)})
}
-func (req *pingV4) name() string { return "PING/v4" }
+// PONG/v4
+
+func (req *pongV4) name() string { return "PONG/v4" }
+func (req *pongV4) kind() byte { return p_pongV4 }
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, p_pongV4, req) {
+ if !t.handleReply(fromID, from.IP, req) {
return errUnsolicitedReply
}
return nil
@@ -805,13 +928,16 @@ func (req *pongV4) handle(t *UDPv4, from *net.UDPAddr, fromID enode.ID, mac []by
t.db.UpdateLastPongReceived(fromID, from.IP, time.Now())
}
-func (req *pongV4) name() string { return "PONG/v4" }
+// FINDNODE/v4
+
+func (req *findnodeV4) name() string { return "FINDNODE/v4" }
+func (req *findnodeV4) kind() byte { return p_findnodeV4 }
func (req *findnodeV4) preverify(t *UDPv4, from *net.UDPAddr, fromID enode.ID, fromKey encPubkey) error {
if expired(req.Expiration) {
return errExpired
}
- if time.Since(t.db.LastPongReceived(fromID, from.IP)) > bondExpiration {
+ if !t.checkBond(fromID, from.IP) {
// No endpoint proof pong exists, we don't process the packet. This prevents an
// attack vector where the discovery protocol could be used to amplify traffic in a
// DDOS attack. A malicious actor would send a findnode request with the IP address
@@ -839,23 +965,26 @@ func (req *findnodeV4) handle(t *UDPv4, from *net.UDPAddr, fromID enode.ID, mac
p.Nodes = append(p.Nodes, nodeToRPC(n))
}
if len(p.Nodes) == maxNeighbors {
- t.send(from, fromID, p_neighborsV4, &p)
+ t.send(from, fromID, &p)
p.Nodes = p.Nodes[:0]
sent = true
}
}
if len(p.Nodes) > 0 || !sent {
- t.send(from, fromID, p_neighborsV4, &p)
+ t.send(from, fromID, &p)
}
}
-func (req *findnodeV4) name() string { return "FINDNODE/v4" }
+// NEIGHBORS/v4
+
+func (req *neighborsV4) name() string { return "NEIGHBORS/v4" }
+func (req *neighborsV4) kind() byte { return p_neighborsV4 }
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, p_neighborsV4, req) {
+ if !t.handleReply(fromID, from.IP, req) {
return errUnsolicitedReply
}
return nil
@@ -864,8 +993,39 @@ func (req *neighborsV4) preverify(t *UDPv4, from *net.UDPAddr, fromID enode.ID,
func (req *neighborsV4) handle(t *UDPv4, from *net.UDPAddr, fromID enode.ID, mac []byte) {
}
-func (req *neighborsV4) name() string { return "NEIGHBORS/v4" }
+// ENRREQUEST/v4
-func expired(ts uint64) bool {
- return time.Unix(int64(ts), 0).Before(time.Now())
+func (req *enrRequestV4) name() string { return "ENRREQUEST/v4" }
+func (req *enrRequestV4) kind() byte { return p_enrRequestV4 }
+
+func (req *enrRequestV4) preverify(t *UDPv4, from *net.UDPAddr, fromID enode.ID, fromKey encPubkey) error {
+ if expired(req.Expiration) {
+ return errExpired
+ }
+ if !t.checkBond(fromID, from.IP) {
+ return errUnknownNode
+ }
+ return nil
+}
+
+func (req *enrRequestV4) handle(t *UDPv4, from *net.UDPAddr, fromID enode.ID, mac []byte) {
+ t.send(from, fromID, &enrResponseV4{
+ ReplyTok: mac,
+ Record: *t.localNode.Node().Record(),
+ })
+}
+
+// ENRRESPONSE/v4
+
+func (req *enrResponseV4) name() string { return "ENRRESPONSE/v4" }
+func (req *enrResponseV4) kind() byte { return p_enrResponseV4 }
+
+func (req *enrResponseV4) preverify(t *UDPv4, from *net.UDPAddr, fromID enode.ID, fromKey encPubkey) error {
+ if !t.handleReply(fromID, from.IP, req) {
+ return errUnsolicitedReply
+ }
+ return nil
+}
+
+func (req *enrResponseV4) handle(t *UDPv4, from *net.UDPAddr, fromID enode.ID, mac []byte) {
}
diff --git a/p2p/discover/v4_udp_lookup_test.go b/p2p/discover/v4_udp_lookup_test.go
index 7e12aa4986e91f4b141b14eb7151560f2fd81c76..bc1cdfb089abdaebabad459190a96a45f59e56d8 100644
--- a/p2p/discover/v4_udp_lookup_test.go
+++ b/p2p/discover/v4_udp_lookup_test.go
@@ -54,11 +54,11 @@ func TestUDPv4_Lookup(t *testing.T) {
n, key := lookupTestnet.nodeByAddr(to)
switch p.(type) {
case *pingV4:
- test.packetInFrom(nil, key, to, p_pongV4, &pongV4{Expiration: futureExp, ReplyTok: hash})
+ test.packetInFrom(nil, key, to, &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})
+ test.packetInFrom(nil, key, to, &neighborsV4{Expiration: futureExp, Nodes: nodes})
}
})
}
diff --git a/p2p/discover/v4_udp_test.go b/p2p/discover/v4_udp_test.go
index 0aa4c01e5e2aacf04d9b1fe292c7fa4a88bf10e1..9d7badea197452d02218988f64241e221f60ba9c 100644
--- a/p2p/discover/v4_udp_test.go
+++ b/p2p/discover/v4_udp_test.go
@@ -37,6 +37,7 @@ import (
"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/p2p/enr"
"github.com/ethereum/go-ethereum/rlp"
)
@@ -91,19 +92,19 @@ func (test *udpTest) close() {
}
// handles a packet as if it had been sent to the transport.
-func (test *udpTest) packetIn(wantError error, ptype byte, data packetV4) {
+func (test *udpTest) packetIn(wantError error, data packetV4) {
test.t.Helper()
- test.packetInFrom(wantError, test.remotekey, test.remoteaddr, ptype, data)
+ test.packetInFrom(wantError, test.remotekey, test.remoteaddr, 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 packetV4) {
+func (test *udpTest) packetInFrom(wantError error, key *ecdsa.PrivateKey, addr *net.UDPAddr, data packetV4) {
test.t.Helper()
- enc, _, err := test.udp.encode(key, ptype, data)
+ enc, _, err := test.udp.encode(key, data)
if err != nil {
- test.t.Errorf("packet (%d) encode error: %v", ptype, err)
+ test.t.Errorf("%s encode error: %v", data.name(), err)
}
test.sent = append(test.sent, enc)
if err = test.udp.handlePacket(addr, enc); err != wantError {
@@ -139,10 +140,10 @@ func TestUDPv4_packetErrors(t *testing.T) {
test := newUDPTest(t)
defer test.close()
- 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})
+ test.packetIn(errExpired, &pingV4{From: testRemote, To: testLocalAnnounced, Version: 4})
+ test.packetIn(errUnsolicitedReply, &pongV4{ReplyTok: []byte{}, Expiration: futureExp})
+ test.packetIn(errUnknownNode, &findnodeV4{Expiration: futureExp})
+ test.packetIn(errUnsolicitedReply, &neighborsV4{Expiration: futureExp})
}
func TestUDPv4_pingTimeout(t *testing.T) {
@@ -153,11 +154,21 @@ func TestUDPv4_pingTimeout(t *testing.T) {
key := newkey()
toaddr := &net.UDPAddr{IP: net.ParseIP("1.2.3.4"), Port: 2222}
node := enode.NewV4(&key.PublicKey, toaddr.IP, 0, toaddr.Port)
- if err := test.udp.ping(node); err != errTimeout {
+ if _, err := test.udp.ping(node); err != errTimeout {
t.Error("expected timeout error, got", err)
}
}
+type testPacket byte
+
+func (req testPacket) kind() byte { return byte(req) }
+func (req testPacket) name() string { return "" }
+func (req testPacket) preverify(*UDPv4, *net.UDPAddr, enode.ID, encPubkey) error {
+ return nil
+}
+func (req testPacket) handle(*UDPv4, *net.UDPAddr, enode.ID, []byte) {
+}
+
func TestUDPv4_responseTimeouts(t *testing.T) {
t.Parallel()
test := newUDPTest(t)
@@ -192,7 +203,7 @@ func TestUDPv4_responseTimeouts(t *testing.T) {
p.errc = nilErr
test.udp.addReplyMatcher <- p
time.AfterFunc(randomDuration(60*time.Millisecond), func() {
- if !test.udp.handleReply(p.from, p.ip, p.ptype, nil) {
+ if !test.udp.handleReply(p.from, p.ip, testPacket(p.ptype)) {
t.Logf("not matched: %v", p)
}
})
@@ -277,7 +288,7 @@ func TestUDPv4_findnode(t *testing.T) {
// check that closest neighbors are returned.
expected := test.table.closest(testTarget.id(), bucketSize, true)
- test.packetIn(nil, p_findnodeV4, &findnodeV4{Target: testTarget, Expiration: futureExp})
+ test.packetIn(nil, &findnodeV4{Target: testTarget, Expiration: futureExp})
waitNeighbors := func(want []*node) {
test.waitPacketOut(func(p *neighborsV4, to *net.UDPAddr, hash []byte) {
if len(p.Nodes) != len(want) {
@@ -340,8 +351,8 @@ func TestUDPv4_findnodeMultiReply(t *testing.T) {
for i := range list {
rpclist[i] = nodeToRPC(list[i])
}
- test.packetIn(nil, p_neighborsV4, &neighborsV4{Expiration: futureExp, Nodes: rpclist[:2]})
- test.packetIn(nil, p_neighborsV4, &neighborsV4{Expiration: futureExp, Nodes: rpclist[2:]})
+ test.packetIn(nil, &neighborsV4{Expiration: futureExp, Nodes: rpclist[:2]})
+ test.packetIn(nil, &neighborsV4{Expiration: futureExp, Nodes: rpclist[2:]})
// check that the sent neighbors are all returned by findnode
select {
@@ -357,6 +368,7 @@ func TestUDPv4_findnodeMultiReply(t *testing.T) {
}
}
+// This test checks that reply matching of pong verifies the ping hash.
func TestUDPv4_pingMatch(t *testing.T) {
test := newUDPTest(t)
defer test.close()
@@ -364,22 +376,23 @@ func TestUDPv4_pingMatch(t *testing.T) {
randToken := make([]byte, 32)
crand.Read(randToken)
- test.packetIn(nil, p_pingV4, &pingV4{From: testRemote, To: testLocalAnnounced, Version: 4, Expiration: futureExp})
+ test.packetIn(nil, &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})
+ test.packetIn(errUnsolicitedReply, &pongV4{ReplyTok: randToken, To: testLocalAnnounced, Expiration: futureExp})
}
+// This test checks that reply matching of pong verifies the sender IP address.
func TestUDPv4_pingMatchIP(t *testing.T) {
test := newUDPTest(t)
defer test.close()
- test.packetIn(nil, p_pingV4, &pingV4{From: testRemote, To: testLocalAnnounced, Version: 4, Expiration: futureExp})
+ test.packetIn(nil, &pingV4{From: testRemote, To: testLocalAnnounced, Version: 4, Expiration: futureExp})
test.waitPacketOut(func(*pongV4, *net.UDPAddr, []byte) {})
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{
+ test.packetInFrom(errUnsolicitedReply, test.remotekey, wrongAddr, &pongV4{
ReplyTok: hash,
To: testLocalAnnounced,
Expiration: futureExp,
@@ -394,9 +407,9 @@ func TestUDPv4_successfulPing(t *testing.T) {
defer test.close()
// The remote side sends a ping packet to initiate the exchange.
- go test.packetIn(nil, p_pingV4, &pingV4{From: testRemote, To: testLocalAnnounced, Version: 4, Expiration: futureExp})
+ go test.packetIn(nil, &pingV4{From: testRemote, To: testLocalAnnounced, Version: 4, Expiration: futureExp})
- // the ping is replied to.
+ // The ping is replied to.
test.waitPacketOut(func(p *pongV4, to *net.UDPAddr, hash []byte) {
pinghash := test.sent[0][:macSize]
if !bytes.Equal(p.ReplyTok, pinghash) {
@@ -413,7 +426,7 @@ func TestUDPv4_successfulPing(t *testing.T) {
}
})
- // remote is unknown, the table pings back.
+ // Remote is unknown, the table pings back.
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())
@@ -427,10 +440,10 @@ func TestUDPv4_successfulPing(t *testing.T) {
if !reflect.DeepEqual(p.To, wantTo) {
t.Errorf("got ping.To %v, want %v", p.To, wantTo)
}
- test.packetIn(nil, p_pongV4, &pongV4{ReplyTok: hash, Expiration: futureExp})
+ test.packetIn(nil, &pongV4{ReplyTok: hash, Expiration: futureExp})
})
- // the node should be added to the table shortly after getting the
+ // The node should be added to the table shortly after getting the
// pong packet.
select {
case n := <-added:
@@ -452,6 +465,45 @@ func TestUDPv4_successfulPing(t *testing.T) {
}
}
+// This test checks that EIP-868 requests work.
+func TestUDPv4_EIP868(t *testing.T) {
+ test := newUDPTest(t)
+ defer test.close()
+
+ test.udp.localNode.Set(enr.WithEntry("foo", "bar"))
+ wantNode := test.udp.localNode.Node()
+
+ // ENR requests aren't allowed before endpoint proof.
+ test.packetIn(errUnknownNode, &enrRequestV4{Expiration: futureExp})
+
+ // Perform endpoint proof and check for sequence number in packet tail.
+ test.packetIn(nil, &pingV4{Expiration: futureExp})
+ test.waitPacketOut(func(p *pongV4, addr *net.UDPAddr, hash []byte) {
+ if seq := seqFromTail(p.Rest); seq != wantNode.Seq() {
+ t.Errorf("wrong sequence number in pong: %d, want %d", seq, wantNode.Seq())
+ }
+ })
+ test.waitPacketOut(func(p *pingV4, addr *net.UDPAddr, hash []byte) {
+ if seq := seqFromTail(p.Rest); seq != wantNode.Seq() {
+ t.Errorf("wrong sequence number in ping: %d, want %d", seq, wantNode.Seq())
+ }
+ test.packetIn(nil, &pongV4{Expiration: futureExp, ReplyTok: hash})
+ })
+
+ // Request should work now.
+ test.packetIn(nil, &enrRequestV4{Expiration: futureExp})
+ test.waitPacketOut(func(p *enrResponseV4, addr *net.UDPAddr, hash []byte) {
+ n, err := enode.New(enode.ValidSchemes, &p.Record)
+ if err != nil {
+ t.Fatalf("invalid record: %v", err)
+ }
+ if !reflect.DeepEqual(n, wantNode) {
+ t.Fatalf("wrong node in enrResponse: %v", n)
+ }
+ })
+}
+
+// EIP-8 test vectors.
var testPackets = []struct {
input string
wantPacket interface{}