p2p/discover: add node URL functions, distinguish TCP/UDP ports

The discovery RPC protocol does not yet distinguish TCP and UDP ports.
But it can't hurt to do so in our internal model.
pull/292/head
Felix Lange 10 years ago
parent 56f777b2fc
commit 8564eb9f7e
  1. 289
      p2p/discover/node.go
  2. 201
      p2p/discover/node_test.go
  3. 197
      p2p/discover/table.go
  4. 116
      p2p/discover/table_test.go
  5. 32
      p2p/discover/udp.go
  6. 13
      p2p/discover/udp_test.go
  7. 7
      p2p/server.go
  8. 3
      p2p/server_test.go

@ -0,0 +1,289 @@
package discover
import (
"crypto/ecdsa"
"crypto/elliptic"
"encoding/hex"
"errors"
"fmt"
"io"
"math/rand"
"net"
"net/url"
"strconv"
"strings"
"time"
"github.com/ethereum/go-ethereum/crypto/secp256k1"
"github.com/ethereum/go-ethereum/rlp"
)
// Node represents a host on the network.
type Node struct {
ID NodeID
IP net.IP
DiscPort int // UDP listening port for discovery protocol
TCPPort int // TCP listening port for RLPx
active time.Time
}
func newNode(id NodeID, addr *net.UDPAddr) *Node {
return &Node{
ID: id,
IP: addr.IP,
DiscPort: addr.Port,
TCPPort: addr.Port,
active: time.Now(),
}
}
func (n *Node) isValid() bool {
// TODO: don't accept localhost, LAN addresses from internet hosts
return !n.IP.IsMulticast() && !n.IP.IsUnspecified() && n.TCPPort != 0 && n.DiscPort != 0
}
// The string representation of a Node is a URL.
// Please see ParseNode for a description of the format.
func (n *Node) String() string {
addr := net.TCPAddr{IP: n.IP, Port: n.TCPPort}
u := url.URL{
Scheme: "enode",
User: url.User(fmt.Sprintf("%x", n.ID[:])),
Host: addr.String(),
}
if n.DiscPort != n.TCPPort {
u.RawQuery = "discport=" + strconv.Itoa(n.DiscPort)
}
return u.String()
}
// ParseNode parses a node URL.
//
// A node URL has scheme "enode".
//
// The hexadecimal node ID is encoded in the username portion of the
// URL, separated from the host by an @ sign. The hostname can only be
// given as an IP address, DNS domain names are not allowed. The port
// in the host name section is the TCP listening port. If the TCP and
// UDP (discovery) ports differ, the UDP port is specified as query
// parameter "discport".
//
// In the following example, the node URL describes
// a node with IP address 10.3.58.6, TCP listening port 30303
// and UDP discovery port 30301.
//
// enode://<hex node id>@10.3.58.6:30303?discport=30301
func ParseNode(rawurl string) (*Node, error) {
var n Node
u, err := url.Parse(rawurl)
if u.Scheme != "enode" {
return nil, errors.New("invalid URL scheme, want \"enode\"")
}
if u.User == nil {
return nil, errors.New("does not contain node ID")
}
if n.ID, err = HexID(u.User.String()); err != nil {
return nil, fmt.Errorf("invalid node ID (%v)", err)
}
ip, port, err := net.SplitHostPort(u.Host)
if err != nil {
return nil, fmt.Errorf("invalid host: %v", err)
}
if n.IP = net.ParseIP(ip); n.IP == nil {
return nil, errors.New("invalid IP address")
}
if n.TCPPort, err = strconv.Atoi(port); err != nil {
return nil, errors.New("invalid port")
}
qv := u.Query()
if qv.Get("discport") == "" {
n.DiscPort = n.TCPPort
} else {
if n.DiscPort, err = strconv.Atoi(qv.Get("discport")); err != nil {
return nil, errors.New("invalid discport in query")
}
}
return &n, nil
}
// MustParseNode parses a node URL. It panics if the URL is not valid.
func MustParseNode(rawurl string) *Node {
n, err := ParseNode(rawurl)
if err != nil {
panic("invalid node URL: " + err.Error())
}
return n
}
func (n Node) EncodeRLP(w io.Writer) error {
return rlp.Encode(w, rpcNode{IP: n.IP.String(), Port: uint16(n.TCPPort), ID: n.ID})
}
func (n *Node) DecodeRLP(s *rlp.Stream) (err error) {
var ext rpcNode
if err = s.Decode(&ext); err == nil {
n.TCPPort = int(ext.Port)
n.DiscPort = int(ext.Port)
n.ID = ext.ID
if n.IP = net.ParseIP(ext.IP); n.IP == nil {
return errors.New("invalid IP string")
}
}
return err
}
// NodeID is a unique identifier for each node.
// The node identifier is a marshaled elliptic curve public key.
type NodeID [512 / 8]byte
// NodeID prints as a long hexadecimal number.
func (n NodeID) String() string {
return fmt.Sprintf("%#x", n[:])
}
// The Go syntax representation of a NodeID is a call to HexID.
func (n NodeID) GoString() string {
return fmt.Sprintf("discover.HexID(\"%#x\")", n[:])
}
// HexID converts a hex string to a NodeID.
// The string may be prefixed with 0x.
func HexID(in string) (NodeID, error) {
if strings.HasPrefix(in, "0x") {
in = in[2:]
}
var id NodeID
b, err := hex.DecodeString(in)
if err != nil {
return id, err
} else if len(b) != len(id) {
return id, fmt.Errorf("wrong length, need %d hex bytes", len(id))
}
copy(id[:], b)
return id, nil
}
// MustHexID converts a hex string to a NodeID.
// It panics if the string is not a valid NodeID.
func MustHexID(in string) NodeID {
id, err := HexID(in)
if err != nil {
panic(err)
}
return id
}
// PubkeyID returns a marshaled representation of the given public key.
func PubkeyID(pub *ecdsa.PublicKey) NodeID {
var id NodeID
pbytes := elliptic.Marshal(pub.Curve, pub.X, pub.Y)
if len(pbytes)-1 != len(id) {
panic(fmt.Errorf("need %d bit pubkey, got %d bits", (len(id)+1)*8, len(pbytes)))
}
copy(id[:], pbytes[1:])
return id
}
// recoverNodeID computes the public key used to sign the
// given hash from the signature.
func recoverNodeID(hash, sig []byte) (id NodeID, err error) {
pubkey, err := secp256k1.RecoverPubkey(hash, sig)
if err != nil {
return id, err
}
if len(pubkey)-1 != len(id) {
return id, fmt.Errorf("recovered pubkey has %d bits, want %d bits", len(pubkey)*8, (len(id)+1)*8)
}
for i := range id {
id[i] = pubkey[i+1]
}
return id, nil
}
// distcmp compares the distances a->target and b->target.
// Returns -1 if a is closer to target, 1 if b is closer to target
// and 0 if they are equal.
func distcmp(target, a, b NodeID) int {
for i := range target {
da := a[i] ^ target[i]
db := b[i] ^ target[i]
if da > db {
return 1
} else if da < db {
return -1
}
}
return 0
}
// table of leading zero counts for bytes [0..255]
var lzcount = [256]int{
8, 7, 6, 6, 5, 5, 5, 5,
4, 4, 4, 4, 4, 4, 4, 4,
3, 3, 3, 3, 3, 3, 3, 3,
3, 3, 3, 3, 3, 3, 3, 3,
2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
}
// logdist returns the logarithmic distance between a and b, log2(a ^ b).
func logdist(a, b NodeID) int {
lz := 0
for i := range a {
x := a[i] ^ b[i]
if x == 0 {
lz += 8
} else {
lz += lzcount[x]
break
}
}
return len(a)*8 - lz
}
// randomID returns a random NodeID such that logdist(a, b) == n
func randomID(a NodeID, n int) (b NodeID) {
if n == 0 {
return a
}
// flip bit at position n, fill the rest with random bits
b = a
pos := len(a) - n/8 - 1
bit := byte(0x01) << (byte(n%8) - 1)
if bit == 0 {
pos++
bit = 0x80
}
b[pos] = a[pos]&^bit | ^a[pos]&bit // TODO: randomize end bits
for i := pos + 1; i < len(a); i++ {
b[i] = byte(rand.Intn(255))
}
return b
}

@ -0,0 +1,201 @@
package discover
import (
"math/big"
"math/rand"
"net"
"reflect"
"testing"
"testing/quick"
"time"
"github.com/ethereum/go-ethereum/crypto"
)
var (
quickrand = rand.New(rand.NewSource(time.Now().Unix()))
quickcfg = &quick.Config{MaxCount: 5000, Rand: quickrand}
)
var parseNodeTests = []struct {
rawurl string
wantError string
wantResult *Node
}{
{
rawurl: "http://foobar",
wantError: `invalid URL scheme, want "enode"`,
},
{
rawurl: "enode://foobar",
wantError: `does not contain node ID`,
},
{
rawurl: "enode://01010101@123.124.125.126:3",
wantError: `invalid node ID (wrong length, need 64 hex bytes)`,
},
{
rawurl: "enode://1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439@hostname:3",
wantError: `invalid IP address`,
},
{
rawurl: "enode://1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439@127.0.0.1:foo",
wantError: `invalid port`,
},
{
rawurl: "enode://1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439@127.0.0.1:3?discport=foo",
wantError: `invalid discport in query`,
},
{
rawurl: "enode://1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439@127.0.0.1:52150",
wantResult: &Node{
ID: MustHexID("0x1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439"),
IP: net.ParseIP("127.0.0.1"),
DiscPort: 52150,
TCPPort: 52150,
},
},
{
rawurl: "enode://1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439@[::]:52150",
wantResult: &Node{
ID: MustHexID("0x1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439"),
IP: net.ParseIP("::"),
DiscPort: 52150,
TCPPort: 52150,
},
},
{
rawurl: "enode://1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439@127.0.0.1:52150?discport=223344",
wantResult: &Node{
ID: MustHexID("0x1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439"),
IP: net.ParseIP("127.0.0.1"),
DiscPort: 223344,
TCPPort: 52150,
},
},
}
func TestParseNode(t *testing.T) {
for i, test := range parseNodeTests {
n, err := ParseNode(test.rawurl)
if err == nil && test.wantError != "" {
t.Errorf("test %d: got nil error, expected %#q", i, test.wantError)
continue
}
if err != nil && err.Error() != test.wantError {
t.Errorf("test %d: got error %#q, expected %#q", i, err.Error(), test.wantError)
continue
}
if !reflect.DeepEqual(n, test.wantResult) {
t.Errorf("test %d: result mismatch:\ngot: %#v, want: %#v", i, n, test.wantResult)
}
}
}
func TestNodeString(t *testing.T) {
for i, test := range parseNodeTests {
if test.wantError != "" {
continue
}
str := test.wantResult.String()
if str != test.rawurl {
t.Errorf("test %d: Node.String() mismatch:\ngot: %s\nwant: %s", i, str, test.rawurl)
}
}
}
func TestHexID(t *testing.T) {
ref := NodeID{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 106, 217, 182, 31, 165, 174, 1, 67, 7, 235, 220, 150, 66, 83, 173, 205, 159, 44, 10, 57, 42, 161, 26, 188}
id1 := MustHexID("0x000000000000000000000000000000000000000000000000000000000000000000000000000000806ad9b61fa5ae014307ebdc964253adcd9f2c0a392aa11abc")
id2 := MustHexID("000000000000000000000000000000000000000000000000000000000000000000000000000000806ad9b61fa5ae014307ebdc964253adcd9f2c0a392aa11abc")
if id1 != ref {
t.Errorf("wrong id1\ngot %v\nwant %v", id1[:], ref[:])
}
if id2 != ref {
t.Errorf("wrong id2\ngot %v\nwant %v", id2[:], ref[:])
}
}
func TestNodeID_recover(t *testing.T) {
prv := newkey()
hash := make([]byte, 32)
sig, err := crypto.Sign(hash, prv)
if err != nil {
t.Fatalf("signing error: %v", err)
}
pub := PubkeyID(&prv.PublicKey)
recpub, err := recoverNodeID(hash, sig)
if err != nil {
t.Fatalf("recovery error: %v", err)
}
if pub != recpub {
t.Errorf("recovered wrong pubkey:\ngot: %v\nwant: %v", recpub, pub)
}
}
func TestNodeID_distcmp(t *testing.T) {
distcmpBig := func(target, a, b NodeID) int {
tbig := new(big.Int).SetBytes(target[:])
abig := new(big.Int).SetBytes(a[:])
bbig := new(big.Int).SetBytes(b[:])
return new(big.Int).Xor(tbig, abig).Cmp(new(big.Int).Xor(tbig, bbig))
}
if err := quick.CheckEqual(distcmp, distcmpBig, quickcfg); err != nil {
t.Error(err)
}
}
// the random tests is likely to miss the case where they're equal.
func TestNodeID_distcmpEqual(t *testing.T) {
base := NodeID{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15}
x := NodeID{15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0}
if distcmp(base, x, x) != 0 {
t.Errorf("distcmp(base, x, x) != 0")
}
}
func TestNodeID_logdist(t *testing.T) {
logdistBig := func(a, b NodeID) int {
abig, bbig := new(big.Int).SetBytes(a[:]), new(big.Int).SetBytes(b[:])
return new(big.Int).Xor(abig, bbig).BitLen()
}
if err := quick.CheckEqual(logdist, logdistBig, quickcfg); err != nil {
t.Error(err)
}
}
// the random tests is likely to miss the case where they're equal.
func TestNodeID_logdistEqual(t *testing.T) {
x := NodeID{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15}
if logdist(x, x) != 0 {
t.Errorf("logdist(x, x) != 0")
}
}
func TestNodeID_randomID(t *testing.T) {
// we don't use quick.Check here because its output isn't
// very helpful when the test fails.
for i := 0; i < quickcfg.MaxCount; i++ {
a := gen(NodeID{}, quickrand).(NodeID)
dist := quickrand.Intn(len(NodeID{}) * 8)
result := randomID(a, dist)
actualdist := logdist(result, a)
if dist != actualdist {
t.Log("a: ", a)
t.Log("result:", result)
t.Fatalf("#%d: distance of result is %d, want %d", i, actualdist, dist)
}
}
}
func (NodeID) Generate(rand *rand.Rand, size int) reflect.Value {
var id NodeID
m := rand.Intn(len(id))
for i := len(id) - 1; i > m; i-- {
id[i] = byte(rand.Uint32())
}
return reflect.ValueOf(id)
}

@ -7,20 +7,10 @@
package discover
import (
"crypto/ecdsa"
"crypto/elliptic"
"encoding/hex"
"fmt"
"io"
"math/rand"
"net"
"sort"
"strings"
"sync"
"time"
"github.com/ethereum/go-ethereum/crypto/secp256k1"
"github.com/ethereum/go-ethereum/rlp"
)
const (
@ -53,36 +43,10 @@ type bucket struct {
entries []*Node
}
// Node represents node metadata that is stored in the table.
type Node struct {
Addr *net.UDPAddr
ID NodeID
active time.Time
}
type rpcNode struct {
IP string
Port uint16
ID NodeID
}
func (n Node) EncodeRLP(w io.Writer) error {
return rlp.Encode(w, rpcNode{IP: n.Addr.IP.String(), Port: uint16(n.Addr.Port), ID: n.ID})
}
func (n *Node) DecodeRLP(s *rlp.Stream) (err error) {
var ext rpcNode
if err = s.Decode(&ext); err == nil {
n.Addr = &net.UDPAddr{IP: net.ParseIP(ext.IP), Port: int(ext.Port)}
n.ID = ext.ID
}
return err
}
func newTable(t transport, ourID NodeID, ourAddr *net.UDPAddr) *Table {
tab := &Table{net: t, self: &Node{ID: ourID, Addr: ourAddr}}
tab := &Table{net: t, self: newNode(ourID, ourAddr)}
for i := range tab.buckets {
tab.buckets[i] = &bucket{}
tab.buckets[i] = new(bucket)
}
return tab
}
@ -217,7 +181,7 @@ func (tab *Table) len() (n int) {
func (tab *Table) bumpOrAdd(node NodeID, from *net.UDPAddr) (n *Node) {
b := tab.buckets[logdist(tab.self.ID, node)]
if n = b.bump(node); n == nil {
n = &Node{ID: node, Addr: from, active: time.Now()}
n = newNode(node, from)
if len(b.entries) == bucketSize {
tab.pingReplace(n, b)
} else {
@ -238,6 +202,7 @@ func (tab *Table) pingReplace(n *Node, b *bucket) {
tab.mutex.Lock()
if len(b.entries) > 0 && b.entries[len(b.entries)-1] == old {
// slide down other entries and put the new one in front.
// TODO: insert in correct position to keep the order
copy(b.entries[1:], b.entries)
b.entries[0] = n
}
@ -312,157 +277,3 @@ func (h *nodesByDistance) push(n *Node, maxElems int) {
h.entries[ix] = n
}
}
// NodeID is a unique identifier for each node.
// The node identifier is a marshaled elliptic curve public key.
type NodeID [512 / 8]byte
// NodeID prints as a long hexadecimal number.
func (n NodeID) String() string {
return fmt.Sprintf("%#x", n[:])
}
// The Go syntax representation of a NodeID is a call to HexID.
func (n NodeID) GoString() string {
return fmt.Sprintf("HexID(\"%#x\")", n[:])
}
// HexID converts a hex string to a NodeID.
// The string may be prefixed with 0x.
func HexID(in string) (NodeID, error) {
if strings.HasPrefix(in, "0x") {
in = in[2:]
}
var id NodeID
b, err := hex.DecodeString(in)
if err != nil {
return id, err
} else if len(b) != len(id) {
return id, fmt.Errorf("wrong length, need %d hex bytes", len(id))
}
copy(id[:], b)
return id, nil
}
// MustHexID converts a hex string to a NodeID.
// It panics if the string is not a valid NodeID.
func MustHexID(in string) NodeID {
id, err := HexID(in)
if err != nil {
panic(err)
}
return id
}
func PubkeyID(pub *ecdsa.PublicKey) NodeID {
var id NodeID
pbytes := elliptic.Marshal(pub.Curve, pub.X, pub.Y)
if len(pbytes)-1 != len(id) {
panic(fmt.Errorf("invalid key: need %d bit pubkey, got %d bits", (len(id)+1)*8, len(pbytes)))
}
copy(id[:], pbytes[1:])
return id
}
// recoverNodeID computes the public key used to sign the
// given hash from the signature.
func recoverNodeID(hash, sig []byte) (id NodeID, err error) {
pubkey, err := secp256k1.RecoverPubkey(hash, sig)
if err != nil {
return id, err
}
if len(pubkey)-1 != len(id) {
return id, fmt.Errorf("recovered pubkey has %d bits, want %d bits", len(pubkey)*8, (len(id)+1)*8)
}
for i := range id {
id[i] = pubkey[i+1]
}
return id, nil
}
// distcmp compares the distances a->target and b->target.
// Returns -1 if a is closer to target, 1 if b is closer to target
// and 0 if they are equal.
func distcmp(target, a, b NodeID) int {
for i := range target {
da := a[i] ^ target[i]
db := b[i] ^ target[i]
if da > db {
return 1
} else if da < db {
return -1
}
}
return 0
}
// table of leading zero counts for bytes [0..255]
var lzcount = [256]int{
8, 7, 6, 6, 5, 5, 5, 5,
4, 4, 4, 4, 4, 4, 4, 4,
3, 3, 3, 3, 3, 3, 3, 3,
3, 3, 3, 3, 3, 3, 3, 3,
2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
}
// logdist returns the logarithmic distance between a and b, log2(a ^ b).
func logdist(a, b NodeID) int {
lz := 0
for i := range a {
x := a[i] ^ b[i]
if x == 0 {
lz += 8
} else {
lz += lzcount[x]
break
}
}
return len(a)*8 - lz
}
// randomID returns a random NodeID such that logdist(a, b) == n
func randomID(a NodeID, n int) (b NodeID) {
if n == 0 {
return a
}
// flip bit at position n, fill the rest with random bits
b = a
pos := len(a) - n/8 - 1
bit := byte(0x01) << (byte(n%8) - 1)
if bit == 0 {
pos++
bit = 0x80
}
b[pos] = a[pos]&^bit | ^a[pos]&bit // TODO: randomize end bits
for i := pos + 1; i < len(a); i++ {
b[i] = byte(rand.Intn(255))
}
return b
}

@ -4,7 +4,6 @@ import (
"crypto/ecdsa"
"errors"
"fmt"
"math/big"
"math/rand"
"net"
"reflect"
@ -15,107 +14,6 @@ import (
"github.com/ethereum/go-ethereum/crypto"
)
var (
quickrand = rand.New(rand.NewSource(time.Now().Unix()))
quickcfg = &quick.Config{MaxCount: 5000, Rand: quickrand}
)
func TestHexID(t *testing.T) {
ref := NodeID{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 106, 217, 182, 31, 165, 174, 1, 67, 7, 235, 220, 150, 66, 83, 173, 205, 159, 44, 10, 57, 42, 161, 26, 188}
id1 := MustHexID("0x000000000000000000000000000000000000000000000000000000000000000000000000000000806ad9b61fa5ae014307ebdc964253adcd9f2c0a392aa11abc")
id2 := MustHexID("000000000000000000000000000000000000000000000000000000000000000000000000000000806ad9b61fa5ae014307ebdc964253adcd9f2c0a392aa11abc")
if id1 != ref {
t.Errorf("wrong id1\ngot %v\nwant %v", id1[:], ref[:])
}
if id2 != ref {
t.Errorf("wrong id2\ngot %v\nwant %v", id2[:], ref[:])
}
}
func TestNodeID_recover(t *testing.T) {
prv := newkey()
hash := make([]byte, 32)
sig, err := crypto.Sign(hash, prv)
if err != nil {
t.Fatalf("signing error: %v", err)
}
pub := PubkeyID(&prv.PublicKey)
recpub, err := recoverNodeID(hash, sig)
if err != nil {
t.Fatalf("recovery error: %v", err)
}
if pub != recpub {
t.Errorf("recovered wrong pubkey:\ngot: %v\nwant: %v", recpub, pub)
}
}
func TestNodeID_distcmp(t *testing.T) {
distcmpBig := func(target, a, b NodeID) int {
tbig := new(big.Int).SetBytes(target[:])
abig := new(big.Int).SetBytes(a[:])
bbig := new(big.Int).SetBytes(b[:])
return new(big.Int).Xor(tbig, abig).Cmp(new(big.Int).Xor(tbig, bbig))
}
if err := quick.CheckEqual(distcmp, distcmpBig, quickcfg); err != nil {
t.Error(err)
}
}
// the random tests is likely to miss the case where they're equal.
func TestNodeID_distcmpEqual(t *testing.T) {
base := NodeID{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15}
x := NodeID{15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0}
if distcmp(base, x, x) != 0 {
t.Errorf("distcmp(base, x, x) != 0")
}
}
func TestNodeID_logdist(t *testing.T) {
logdistBig := func(a, b NodeID) int {
abig, bbig := new(big.Int).SetBytes(a[:]), new(big.Int).SetBytes(b[:])
return new(big.Int).Xor(abig, bbig).BitLen()
}
if err := quick.CheckEqual(logdist, logdistBig, quickcfg); err != nil {
t.Error(err)
}
}
// the random tests is likely to miss the case where they're equal.
func TestNodeID_logdistEqual(t *testing.T) {
x := NodeID{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15}
if logdist(x, x) != 0 {
t.Errorf("logdist(x, x) != 0")
}
}
func TestNodeID_randomID(t *testing.T) {
// we don't use quick.Check here because its output isn't
// very helpful when the test fails.
for i := 0; i < quickcfg.MaxCount; i++ {
a := gen(NodeID{}, quickrand).(NodeID)
dist := quickrand.Intn(len(NodeID{}) * 8)
result := randomID(a, dist)
actualdist := logdist(result, a)
if dist != actualdist {
t.Log("a: ", a)
t.Log("result:", result)
t.Fatalf("#%d: distance of result is %d, want %d", i, actualdist, dist)
}
}
}
func (NodeID) Generate(rand *rand.Rand, size int) reflect.Value {
var id NodeID
m := rand.Intn(len(id))
for i := len(id) - 1; i > m; i-- {
id[i] = byte(rand.Uint32())
}
return reflect.ValueOf(id)
}
func TestTable_bumpOrAddPingReplace(t *testing.T) {
pingC := make(pingC)
tab := newTable(pingC, NodeID{}, &net.UDPAddr{})
@ -123,7 +21,7 @@ func TestTable_bumpOrAddPingReplace(t *testing.T) {
// this bumpOrAdd should not replace the last node
// because the node replies to ping.
new := tab.bumpOrAdd(randomID(tab.self.ID, 200), nil)
new := tab.bumpOrAdd(randomID(tab.self.ID, 200), &net.UDPAddr{})
pinged := <-pingC
if pinged != last.ID {
@ -149,7 +47,7 @@ func TestTable_bumpOrAddPingTimeout(t *testing.T) {
// this bumpOrAdd should replace the last node
// because the node does not reply to ping.
new := tab.bumpOrAdd(randomID(tab.self.ID, 200), nil)
new := tab.bumpOrAdd(randomID(tab.self.ID, 200), &net.UDPAddr{})
// wait for async bucket update. damn. this needs to go away.
time.Sleep(2 * time.Millisecond)
@ -329,19 +227,17 @@ type findnodeOracle struct {
}
func (t findnodeOracle) findnode(n *Node, target NodeID) ([]*Node, error) {
t.t.Logf("findnode query at dist %d", n.Addr.Port)
t.t.Logf("findnode query at dist %d", n.DiscPort)
// current log distance is encoded in port number
var result []*Node
switch port := n.Addr.Port; port {
switch n.DiscPort {
case 0:
panic("query to node at distance 0")
case 1:
result = append(result, &Node{ID: t.target, Addr: &net.UDPAddr{Port: 0}})
default:
// TODO: add more randomness to distances
port--
next := n.DiscPort - 1
for i := 0; i < bucketSize; i++ {
result = append(result, &Node{ID: randomID(t.target, port), Addr: &net.UDPAddr{Port: port}})
result = append(result, &Node{ID: randomID(t.target, next), DiscPort: next})
}
}
return result, nil

@ -69,6 +69,12 @@ type (
}
)
type rpcNode struct {
IP string
Port uint16
ID NodeID
}
// udp implements the RPC protocol.
type udp struct {
conn *net.UDPConn
@ -121,7 +127,7 @@ func ListenUDP(priv *ecdsa.PrivateKey, laddr string) (*Table, error) {
return nil, err
}
net.Table = newTable(net, PubkeyID(&priv.PublicKey), realaddr)
log.Debugf("Listening on %v, my ID %x\n", realaddr, net.self.ID[:])
log.Debugf("Listening, %v\n", net.self)
return net.Table, nil
}
@ -159,8 +165,8 @@ func (t *udp) ping(e *Node) error {
// TODO: maybe check for ReplyTo field in callback to measure RTT
errc := t.pending(e.ID, pongPacket, func(interface{}) bool { return true })
t.send(e, pingPacket, ping{
IP: t.self.Addr.String(),
Port: uint16(t.self.Addr.Port),
IP: t.self.IP.String(),
Port: uint16(t.self.TCPPort),
Expiration: uint64(time.Now().Add(expiration).Unix()),
})
return <-errc
@ -176,7 +182,7 @@ func (t *udp) findnode(to *Node, target NodeID) ([]*Node, error) {
for i := 0; i < len(reply.Nodes); i++ {
nreceived++
n := reply.Nodes[i]
if validAddr(n.Addr) && n.ID != t.self.ID {
if n.ID != t.self.ID && n.isValid() {
nodes = append(nodes, n)
}
}
@ -191,10 +197,6 @@ func (t *udp) findnode(to *Node, target NodeID) ([]*Node, error) {
return nodes, err
}
func validAddr(a *net.UDPAddr) bool {
return !a.IP.IsMulticast() && !a.IP.IsUnspecified() && a.Port != 0
}
// pending adds a reply callback to the pending reply queue.
// see the documentation of type pending for a detailed explanation.
func (t *udp) pending(id NodeID, ptype byte, callback func(interface{}) bool) <-chan error {
@ -302,8 +304,9 @@ func (t *udp) send(to *Node, ptype byte, req interface{}) error {
// the future.
copy(packet, crypto.Sha3(packet[macSize:]))
log.DebugDetailf(">>> %v %T %v\n", to.Addr, req, req)
if _, err = t.conn.WriteToUDP(packet, to.Addr); err != nil {
toaddr := &net.UDPAddr{IP: to.IP, Port: to.DiscPort}
log.DebugDetailf(">>> %v %T %v\n", toaddr, req, req)
if _, err = t.conn.WriteToUDP(packet, toaddr); err != nil {
log.DebugDetailln("UDP send failed:", err)
}
return err
@ -365,11 +368,14 @@ func (req *ping) handle(t *udp, from *net.UDPAddr, fromID NodeID, mac []byte) er
return errExpired
}
t.mutex.Lock()
// Note: we're ignoring the provided IP/Port right now.
e := t.bumpOrAdd(fromID, from)
// Note: we're ignoring the provided IP address right now
n := t.bumpOrAdd(fromID, from)
if req.Port != 0 {
n.TCPPort = int(req.Port)
}
t.mutex.Unlock()
t.send(e, pongPacket, pong{
t.send(n, pongPacket, pong{
ReplyTok: mac,
Expiration: uint64(time.Now().Add(expiration).Unix()),
})

@ -4,6 +4,7 @@ import (
logpkg "log"
"net"
"os"
"reflect"
"testing"
"time"
@ -11,7 +12,7 @@ import (
)
func init() {
logger.AddLogSystem(logger.NewStdLogSystem(os.Stdout, logpkg.LstdFlags, logger.DebugLevel))
logger.AddLogSystem(logger.NewStdLogSystem(os.Stdout, logpkg.LstdFlags, logger.ErrorLevel))
}
func TestUDP_ping(t *testing.T) {
@ -52,7 +53,7 @@ func TestUDP_findnode(t *testing.T) {
defer n1.Close()
defer n2.Close()
entry := &Node{ID: NodeID{1}, Addr: &net.UDPAddr{IP: net.IP{1, 2, 3, 4}, Port: 15}}
entry := MustParseNode("enode://9d8a19597e312ef32d76e6b4903bb43d7bcd892d17b769d30b404bd3a4c2dca6c86184b17d0fdeeafe3b01e0e912d990ddc853db3f325d5419f31446543c30be@127.0.0.1:54194")
n2.add([]*Node{entry})
target := randomID(n1.self.ID, 100)
@ -60,7 +61,7 @@ func TestUDP_findnode(t *testing.T) {
if len(result) != 1 {
t.Fatalf("wrong number of results: got %d, want 1", len(result))
}
if result[0].ID != entry.ID {
if !reflect.DeepEqual(result[0], entry) {
t.Errorf("wrong result: got %v, want %v", result[0], entry)
}
}
@ -103,8 +104,10 @@ func TestUDP_findnodeMultiReply(t *testing.T) {
nodes := make([]*Node, bucketSize)
for i := range nodes {
nodes[i] = &Node{
Addr: &net.UDPAddr{IP: net.IP{1, 2, 3, 4}, Port: i + 1},
ID: randomID(n2.self.ID, i+1),
IP: net.IP{1, 2, 3, 4},
DiscPort: i + 1,
TCPPort: i + 1,
ID: randomID(n2.self.ID, i+1),
}
}

@ -136,7 +136,7 @@ func (srv *Server) PeerCount() int {
// SuggestPeer creates a connection to the given Node if it
// is not already connected.
func (srv *Server) SuggestPeer(ip net.IP, port int, id discover.NodeID) {
srv.peerConnect <- &discover.Node{ID: id, Addr: &net.UDPAddr{IP: ip, Port: port}}
srv.peerConnect <- &discover.Node{ID: id, IP: ip, TCPPort: port}
}
// Broadcast sends an RLP-encoded message to all connected peers.
@ -364,8 +364,9 @@ func (srv *Server) dialLoop() {
}
func (srv *Server) dialNode(dest *discover.Node) {
srvlog.Debugf("Dialing %v\n", dest.Addr)
conn, err := srv.Dialer.Dial("tcp", dest.Addr.String())
addr := &net.TCPAddr{IP: dest.IP, Port: dest.TCPPort}
srvlog.Debugf("Dialing %v\n", dest)
conn, err := srv.Dialer.Dial("tcp", addr.String())
if err != nil {
srvlog.DebugDetailf("dial error: %v", err)
return

@ -91,8 +91,7 @@ func TestServerDial(t *testing.T) {
// tell the server to connect
tcpAddr := listener.Addr().(*net.TCPAddr)
connAddr := &discover.Node{Addr: &net.UDPAddr{IP: tcpAddr.IP, Port: tcpAddr.Port}}
srv.peerConnect <- connAddr
srv.peerConnect <- &discover.Node{IP: tcpAddr.IP, TCPPort: tcpAddr.Port}
select {
case conn := <-accepted:

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