add token manager, add token to request/response, sucessfully perform a STORE request on the python daemon

dht/bitmap.go

@@ -3,27 +3,26 @@ package dht
 import (
 	"crypto/rand"
 	"encoding/hex"
-	"strconv"
 
 	"github.com/lbryio/errors.go"
 	"github.com/lyoshenka/bencode"
 )
 
-type bitmap [nodeIDLength]byte
+type Bitmap [nodeIDLength]byte
 
-func (b bitmap) RawString() string {
+func (b Bitmap) RawString() string {
 	return string(b[:])
 }
 
-func (b bitmap) Hex() string {
+func (b Bitmap) Hex() string {
 	return hex.EncodeToString(b[:])
 }
 
-func (b bitmap) HexShort() string {
+func (b Bitmap) HexShort() string {
 	return hex.EncodeToString(b[:4])
 }
 
-func (b bitmap) Equals(other bitmap) bool {
+func (b Bitmap) Equals(other Bitmap) bool {
 	for k := range b {
 		if b[k] != other[k] {
 			return false
@@ -32,17 +31,17 @@ func (b bitmap) Equals(other bitmap) bool {
 	return true
 }
 
-func (b bitmap) Less(other interface{}) bool {
+func (b Bitmap) Less(other interface{}) bool {
 	for k := range b {
-		if b[k] != other.(bitmap)[k] {
+		if b[k] != other.(Bitmap)[k] {
-			return b[k] < other.(bitmap)[k]
+			return b[k] < other.(Bitmap)[k]
 		}
 	}
 	return false
 }
 
-func (b bitmap) Xor(other bitmap) bitmap {
+func (b Bitmap) Xor(other Bitmap) Bitmap {
-	var ret bitmap
+	var ret Bitmap
 	for k := range b {
 		ret[k] = b[k] ^ other[k]
 	}
@@ -50,7 +49,7 @@ func (b bitmap) Xor(other bitmap) bitmap {
 }
 
 // PrefixLen returns the number of leading 0 bits
-func (b bitmap) PrefixLen() int {
+func (b Bitmap) PrefixLen() int {
 	for i := range b {
 		for j := 0; j < 8; j++ {
 			if (b[i]>>uint8(7-j))&0x1 != 0 {
@@ -61,12 +60,12 @@ func (b bitmap) PrefixLen() int {
 	return numBuckets
 }
 
-func (b bitmap) MarshalBencode() ([]byte, error) {
+func (b Bitmap) MarshalBencode() ([]byte, error) {
 	str := string(b[:])
 	return bencode.EncodeBytes(str)
 }
 
-func (b *bitmap) UnmarshalBencode(encoded []byte) error {
+func (b *Bitmap) UnmarshalBencode(encoded []byte) error {
 	var str string
 	err := bencode.DecodeBytes(encoded, &str)
 	if err != nil {
@@ -79,30 +78,55 @@ func (b *bitmap) UnmarshalBencode(encoded []byte) error {
 	return nil
 }
 
-func newBitmapFromBytes(data []byte) bitmap {
+func BitmapFromBytes(data []byte) (Bitmap, error) {
-	if len(data) != nodeIDLength {
+	var bmp Bitmap
-		panic("invalid bitmap of length " + strconv.Itoa(len(data)))
+
+	if len(data) != len(bmp) {
+		return bmp, errors.Err("invalid bitmap of length %d", len(data))
 	}
 
-	var bmp bitmap
 	copy(bmp[:], data)
-	return bmp
+	return bmp, nil
 }
 
-func newBitmapFromString(data string) bitmap {
+func BitmapFromBytesP(data []byte) Bitmap {
-	return newBitmapFromBytes([]byte(data))
+	bmp, err := BitmapFromBytes(data)
-}
-
-func newBitmapFromHex(hexStr string) bitmap {
-	decoded, err := hex.DecodeString(hexStr)
 	if err != nil {
 		panic(err)
 	}
-	return newBitmapFromBytes(decoded)
+	return bmp
 }
 
-func newRandomBitmap() bitmap {
+func BitmapFromString(data string) (Bitmap, error) {
-	var id bitmap
+	return BitmapFromBytes([]byte(data))
+}
+
+func BitmapFromStringP(data string) Bitmap {
+	bmp, err := BitmapFromString(data)
+	if err != nil {
+		panic(err)
+	}
+	return bmp
+}
+
+func BitmapFromHex(hexStr string) (Bitmap, error) {
+	decoded, err := hex.DecodeString(hexStr)
+	if err != nil {
+		return Bitmap{}, errors.Err(err)
+	}
+	return BitmapFromBytes(decoded)
+}
+
+func BitmapFromHexP(hexStr string) Bitmap {
+	bmp, err := BitmapFromHex(hexStr)
+	if err != nil {
+		panic(err)
+	}
+	return bmp
+}
+
+func RandomBitmapP() Bitmap {
+	var id Bitmap
 	_, err := rand.Read(id[:])
 	if err != nil {
 		panic(err)

dht/bitmap_test.go

@@ -7,19 +7,19 @@ import (
 )
 
 func TestBitmap(t *testing.T) {
-	a := bitmap{
+	a := Bitmap{
 		0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
 		12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
 		24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
 		36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
 	}
-	b := bitmap{
+	b := Bitmap{
 		0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
 		12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
 		24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
 		36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 47, 46,
 	}
-	c := bitmap{
+	c := Bitmap{
 		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,
@@ -46,13 +46,13 @@ func TestBitmap(t *testing.T) {
 	}
 
 	id := "0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef"
-	if newBitmapFromHex(id).Hex() != id {
+	if BitmapFromHexP(id).Hex() != id {
-		t.Error(newBitmapFromHex(id).Hex())
+		t.Error(BitmapFromHexP(id).Hex())
 	}
 }
 
 func TestBitmapMarshal(t *testing.T) {
-	b := newBitmapFromString("123456789012345678901234567890123456789012345678")
+	b := BitmapFromStringP("123456789012345678901234567890123456789012345678")
 	encoded, err := bencode.EncodeBytes(b)
 	if err != nil {
 		t.Error(err)
@@ -66,11 +66,11 @@ func TestBitmapMarshal(t *testing.T) {
 func TestBitmapMarshalEmbedded(t *testing.T) {
 	e := struct {
 		A string
-		B bitmap
+		B Bitmap
 		C int
 	}{
 		A: "1",
-		B: newBitmapFromString("222222222222222222222222222222222222222222222222"),
+		B: BitmapFromStringP("222222222222222222222222222222222222222222222222"),
 		C: 3,
 	}
 
@@ -86,7 +86,7 @@ func TestBitmapMarshalEmbedded(t *testing.T) {
 
 func TestBitmapMarshalEmbedded2(t *testing.T) {
 	encoded, err := bencode.EncodeBytes([]interface{}{
-		newBitmapFromString("333333333333333333333333333333333333333333333333"),
+		BitmapFromStringP("333333333333333333333333333333333333333333333333"),
 	})
 	if err != nil {
 		t.Error(err)
@@ -113,7 +113,7 @@ func TestBitmap_PrefixLen(t *testing.T) {
 	}
 
 	for _, test := range tt {
-		len := newBitmapFromHex(test.str).PrefixLen()
+		len := BitmapFromHexP(test.str).PrefixLen()
 		if len != test.len {
 			t.Errorf("got prefix len %d; expected %d for %s", len, test.len, test.str)
 		}

dht/dht.go

@@ -3,6 +3,7 @@ package dht
 import (
 	"context"
 	"net"
+	"strconv"
 	"strings"
 	"sync"
 	"time"
@@ -28,6 +29,7 @@ const bucketSize = 8       // this is the constant k in the spec
 
 const udpRetry = 3
 const udpTimeout = 10 * time.Second
+const udpMaxMessageLength = 1024 // I think our longest message is ~676 bytes, so I rounded up
 
 const tExpire = 86400 * time.Second    // the time after which a key/value pair expires; this is a time-to-live (TTL) from the original publication date
 const tRefresh = 3600 * time.Second    // the time after which an otherwise unaccessed bucket must be refreshed
@@ -37,6 +39,8 @@ const tRepublish = 86400 * time.Second // the time after which the original publ
 const numBuckets = nodeIDLength * 8
 const compactNodeInfoLength = nodeIDLength + 6
 
+const tokenSecretRotationInterval = 5 * time.Minute // how often the token-generating secret is rotated
+
 // packet represents the information receive from udp.
 type packet struct {
 	data  []byte
@@ -92,6 +96,8 @@ type DHT struct {
 	store *peerStore
 	// transaction manager
 	tm *transactionManager
+	// token manager
+	tokens *tokenManager
 	// stopper to shut down DHT
 	stop *stopOnce.Stopper
 	// wait group for all the things that need to be stopped when DHT shuts down
@@ -106,11 +112,11 @@ func New(config *Config) (*DHT, error) {
 		config = NewStandardConfig()
 	}
 
-	var id bitmap
+	var id Bitmap
 	if config.NodeID == "" {
-		id = newRandomBitmap()
+		id = RandomBitmapP()
 	} else {
-		id = newBitmapFromHex(config.NodeID)
+		id = BitmapFromHexP(config.NodeID)
 	}
 
 	ip, port, err := net.SplitHostPort(config.Address)
@@ -141,8 +147,10 @@ func New(config *Config) (*DHT, error) {
 		stop:    stopOnce.New(),
 		stopWG:  &sync.WaitGroup{},
 		joined:  make(chan struct{}),
+		tokens:  &tokenManager{},
 	}
 	d.tm = newTransactionManager(d)
+	d.tokens.Start(tokenSecretRotationInterval)
 	return d, nil
 }
 
@@ -173,7 +181,7 @@ func (dht *DHT) listen() {
 	dht.stopWG.Add(1)
 	defer dht.stopWG.Done()
 
-	buf := make([]byte, 16384)
+	buf := make([]byte, udpMaxMessageLength)
 
 	for {
 		select {
@@ -212,7 +220,7 @@ func (dht *DHT) join() {
 			continue
 		}
 
-		tmpNode := Node{id: newRandomBitmap(), ip: raddr.IP, port: raddr.Port}
+		tmpNode := Node{id: RandomBitmapP(), ip: raddr.IP, port: raddr.Port}
 		res := dht.tm.Send(tmpNode, Request{Method: pingMethod})
 		if res == nil {
 			log.Errorf("[%s] join: no response from seed node %s", dht.node.id.HexShort(), addr)
@@ -271,12 +279,13 @@ func (dht *DHT) Shutdown() {
 	log.Debugf("[%s] DHT shutting down", dht.node.id.HexShort())
 	dht.stop.Stop()
 	dht.stopWG.Wait()
+	dht.tokens.Stop()
 	dht.conn.Close()
 	log.Debugf("[%s] DHT stopped", dht.node.id.HexShort())
 }
 
 // Get returns the list of nodes that have the blob for the given hash
-func (dht *DHT) Get(hash bitmap) ([]Node, error) {
+func (dht *DHT) Get(hash Bitmap) ([]Node, error) {
 	nf := newNodeFinder(dht, hash, true)
 	res, err := nf.Find()
 	if err != nil {
@@ -290,20 +299,48 @@ func (dht *DHT) Get(hash bitmap) ([]Node, error) {
 }
 
 // Announce announces to the DHT that this node has the blob for the given hash
-func (dht *DHT) Announce(hash bitmap) error {
+func (dht *DHT) Announce(hash Bitmap) error {
 	nf := newNodeFinder(dht, hash, false)
 	res, err := nf.Find()
 	if err != nil {
 		return err
 	}
 
+	// TODO: if this node is closer than farthest peer, store locally and pop farthest peer
+
 	for _, node := range res.Nodes {
+		go dht.storeOnNode(hash, node)
+	}
+
+	return nil
+}
+
+func (dht *DHT) storeOnNode(hash Bitmap, node Node) {
+	dht.stopWG.Add(1)
+	defer dht.stopWG.Done()
+
+	resCh := dht.tm.SendAsync(context.Background(), node, Request{
+		Method: findValueMethod,
+		Arg:    &hash,
+	})
+	var res *Response
+
+	select {
+	case res = <-resCh:
+	case <-dht.stop.Chan():
+		return
+	}
+
+	if res == nil {
+		return // request timed out
+	}
+
 	dht.tm.SendAsync(context.Background(), node, Request{
 		Method: storeMethod,
 		StoreArgs: &storeArgs{
 			BlobHash: hash,
 			Value: storeArgsValue{
-					Token:  "",
+				Token:  res.Token,
 				LbryID: dht.node.id,
 				Port:   dht.node.port,
 			},
@@ -311,11 +348,8 @@ func (dht *DHT) Announce(hash bitmap) error {
 	})
 }
 
-	return nil
-}
-
 func (dht *DHT) PrintState() {
-	log.Printf("DHT state at %s", time.Now().Format(time.RFC822Z))
+	log.Printf("DHT node %s at %s", dht.node.String(), time.Now().Format(time.RFC822Z))
 	log.Printf("Outstanding transactions: %d", dht.tm.Count())
 	log.Printf("Stored hashes: %d", dht.store.CountStoredHashes())
 	log.Printf("Buckets:")
@@ -326,6 +360,34 @@ func (dht *DHT) PrintState() {
 
 func printNodeList(list []Node) {
 	for i, n := range list {
-		log.Printf("%d) %s %s:%d", i, n.id.HexShort(), n.ip.String(), n.port)
+		log.Printf("%d) %s", i, n.String())
 	}
 }
+
+func MakeTestDHT(numNodes int) []*DHT {
+	if numNodes < 1 {
+		return nil
+	}
+
+	ip := "127.0.0.1"
+	firstPort := 21000
+	dhts := make([]*DHT, numNodes)
+
+	for i := 0; i < numNodes; i++ {
+		seeds := []string{}
+		if i > 0 {
+			seeds = []string{ip + ":" + strconv.Itoa(firstPort)}
+		}
+
+		dht, err := New(&Config{Address: ip + ":" + strconv.Itoa(firstPort+i), NodeID: RandomBitmapP().Hex(), SeedNodes: seeds})
+		if err != nil {
+			panic(err)
+		}
+
+		go dht.Start()
+		dht.WaitUntilJoined()
+		dhts[i] = dht
+	}
+
+	return dhts
+}

dht/dht_test.go

@@ -3,7 +3,6 @@ package dht
 import (
 	"math/rand"
 	"net"
-	"strconv"
 	"sync"
 	"testing"
 	"time"
@@ -12,14 +11,14 @@ import (
 )
 
 func TestNodeFinder_FindNodes(t *testing.T) {
-	dhts := makeDHT(t, 3)
+	dhts := MakeTestDHT(3)
 	defer func() {
 		for i := range dhts {
 			dhts[i].Shutdown()
 		}
 	}()
 
-	nf := newNodeFinder(dhts[2], newRandomBitmap(), false)
+	nf := newNodeFinder(dhts[2], RandomBitmapP(), false)
 	res, err := nf.Find()
 	if err != nil {
 		t.Fatal(err)
@@ -55,15 +54,15 @@ func TestNodeFinder_FindNodes(t *testing.T) {
 }
 
 func TestNodeFinder_FindValue(t *testing.T) {
-	dhts := makeDHT(t, 3)
+	dhts := MakeTestDHT(3)
 	defer func() {
 		for i := range dhts {
 			dhts[i].Shutdown()
 		}
 	}()
 
-	blobHashToFind := newRandomBitmap()
+	blobHashToFind := RandomBitmapP()
-	nodeToFind := Node{id: newRandomBitmap(), ip: net.IPv4(1, 2, 3, 4), port: 5678}
+	nodeToFind := Node{id: RandomBitmapP(), ip: net.IPv4(1, 2, 3, 4), port: 5678}
 	dhts[0].store.Upsert(blobHashToFind, nodeToFind)
 
 	nf := newNodeFinder(dhts[2], blobHashToFind, true)
@@ -90,7 +89,7 @@ func TestDHT_LargeDHT(t *testing.T) {
 	rand.Seed(time.Now().UnixNano())
 	log.Println("if this takes longer than 20 seconds, its stuck. idk why it gets stuck sometimes, but its a bug.")
 	nodes := 100
-	dhts := makeDHT(t, nodes)
+	dhts := MakeTestDHT(nodes)
 	defer func() {
 		for _, d := range dhts {
 			go d.Shutdown()
@@ -100,9 +99,9 @@ func TestDHT_LargeDHT(t *testing.T) {
 
 	wg := &sync.WaitGroup{}
 	numIDs := nodes / 2
-	ids := make([]bitmap, numIDs)
+	ids := make([]Bitmap, numIDs)
 	for i := 0; i < numIDs; i++ {
-		ids[i] = newRandomBitmap()
+		ids[i] = RandomBitmapP()
 	}
 	for i := 0; i < numIDs; i++ {
 		go func(i int) {
@@ -116,31 +115,3 @@ func TestDHT_LargeDHT(t *testing.T) {
 
 	dhts[1].PrintState()
 }
-
-func makeDHT(t *testing.T, numNodes int) []*DHT {
-	if numNodes < 1 {
-		return nil
-	}
-
-	ip := "127.0.0.1"
-	firstPort := 21000
-	dhts := make([]*DHT, numNodes)
-
-	for i := 0; i < numNodes; i++ {
-		seeds := []string{}
-		if i > 0 {
-			seeds = []string{ip + ":" + strconv.Itoa(firstPort)}
-		}
-
-		dht, err := New(&Config{Address: ip + ":" + strconv.Itoa(firstPort+i), NodeID: newRandomBitmap().Hex(), SeedNodes: seeds})
-		if err != nil {
-			t.Fatal(err)
-		}
-
-		go dht.Start()
-		dht.WaitUntilJoined()
-		dhts[i] = dht
-	}
-
-	return dhts
-}

dht/message.go

@@ -38,6 +38,8 @@ const (
 	headerNodeIDField    = "2" // node id is 48 bytes long
 	headerPayloadField   = "3"
 	headerArgsField      = "4"
+	contactsField        = "contacts"
+	tokenField           = "token"
 )
 
 type Message interface {
@@ -76,9 +78,9 @@ func newMessageID() messageID {
 
 type Request struct {
 	ID        messageID
-	NodeID    bitmap
+	NodeID    Bitmap
 	Method    string
-	Arg       *bitmap
+	Arg       *Bitmap
 	StoreArgs *storeArgs
 }
 
@@ -87,7 +89,7 @@ func (r Request) MarshalBencode() ([]byte, error) {
 	if r.StoreArgs != nil {
 		args = r.StoreArgs
 	} else if r.Arg != nil {
-		args = []bitmap{*r.Arg}
+		args = []Bitmap{*r.Arg}
 	}
 	return bencode.EncodeBytes(map[string]interface{}{
 		headerTypeField:      requestType,
@@ -101,7 +103,7 @@ func (r Request) MarshalBencode() ([]byte, error) {
 func (r *Request) UnmarshalBencode(b []byte) error {
 	var raw struct {
 		ID     messageID          `bencode:"1"`
-		NodeID bitmap             `bencode:"2"`
+		NodeID Bitmap             `bencode:"2"`
 		Method string             `bencode:"3"`
 		Args   bencode.RawMessage `bencode:"4"`
 	}
@@ -121,7 +123,7 @@ func (r *Request) UnmarshalBencode(b []byte) error {
 			return errors.Prefix("request unmarshal", err)
 		}
 	} else if len(raw.Args) > 2 { // 2 because an empty list is `le`
-		tmp := []bitmap{}
+		tmp := []Bitmap{}
 		err = bencode.DecodeBytes(raw.Args, &tmp)
 		if err != nil {
 			return errors.Prefix("request unmarshal", err)
@@ -143,14 +145,14 @@ func (r Request) ArgsDebug() string {
 
 type storeArgsValue struct {
 	Token  string `bencode:"token"`
-	LbryID bitmap `bencode:"lbryid"`
+	LbryID Bitmap `bencode:"lbryid"`
 	Port   int    `bencode:"port"`
 }
 
 type storeArgs struct {
-	BlobHash  bitmap
+	BlobHash  Bitmap
 	Value     storeArgsValue
-	NodeID    bitmap
+	NodeID    Bitmap
 	SelfStore bool // this is an int on the wire
 }
 
@@ -217,10 +219,11 @@ func (s *storeArgs) UnmarshalBencode(b []byte) error {
 
 type Response struct {
 	ID           messageID
-	NodeID       bitmap
+	NodeID       Bitmap
 	Data         string
 	FindNodeData []Node
 	FindValueKey string
+	Token        string
 }
 
 func (r Response) ArgsDebug() string {
@@ -238,6 +241,11 @@ func (r Response) ArgsDebug() string {
 		str += c.Addr().String() + ":" + c.id.HexShort() + ","
 	}
 	str = strings.TrimRight(str, ",") + "|"
+
+	if r.Token != "" {
+		str += " token: " + hex.EncodeToString([]byte(r.Token))[:8]
+	}
+
 	return str
 }
 
@@ -247,9 +255,16 @@ func (r Response) MarshalBencode() ([]byte, error) {
 		headerMessageIDField: r.ID,
 		headerNodeIDField:    r.NodeID,
 	}
+
 	if r.Data != "" {
+		// ping or store
 		data[headerPayloadField] = r.Data
 	} else if r.FindValueKey != "" {
+		// findValue success
+		if r.Token == "" {
+			return nil, errors.Err("response to findValue must have a token")
+		}
+
 		var contacts [][]byte
 		for _, n := range r.FindNodeData {
 			compact, err := n.MarshalCompact()
@@ -258,9 +273,19 @@ func (r Response) MarshalBencode() ([]byte, error) {
 			}
 			contacts = append(contacts, compact)
 		}
-		data[headerPayloadField] = map[string][][]byte{r.FindValueKey: contacts}
+		data[headerPayloadField] = map[string]interface{}{
+			r.FindValueKey: contacts,
+			tokenField:     r.Token,
+		}
+	} else if r.Token != "" {
+		// findValue failure falling back to findNode
+		data[headerPayloadField] = map[string]interface{}{
+			contactsField: r.FindNodeData,
+			tokenField:    r.Token,
+		}
 	} else {
-		data[headerPayloadField] = map[string][]Node{"contacts": r.FindNodeData}
+		// straight up findNode
+		data[headerPayloadField] = r.FindNodeData
 	}
 
 	return bencode.EncodeBytes(data)
@@ -269,7 +294,7 @@ func (r Response) MarshalBencode() ([]byte, error) {
 func (r *Response) UnmarshalBencode(b []byte) error {
 	var raw struct {
 		ID     messageID          `bencode:"1"`
-		NodeID bitmap             `bencode:"2"`
+		NodeID Bitmap             `bencode:"2"`
 		Data   bencode.RawMessage `bencode:"3"`
 	}
 	err := bencode.DecodeBytes(b, &raw)
@@ -280,15 +305,34 @@ func (r *Response) UnmarshalBencode(b []byte) error {
 	r.ID = raw.ID
 	r.NodeID = raw.NodeID
 
+	// maybe data is a string (response to ping or store)?
 	err = bencode.DecodeBytes(raw.Data, &r.Data)
-	if err != nil {
+	if err == nil {
+		return nil
+	}
+
+	// maybe data is a list of nodes (response to findNode)?
+	err = bencode.DecodeBytes(raw.Data, &r.FindNodeData)
+	if err == nil {
+		return nil
+	}
+
+	// it must be a response to findValue
 	var rawData map[string]bencode.RawMessage
 	err = bencode.DecodeBytes(raw.Data, &rawData)
 	if err != nil {
 		return err
 	}
 
-		if contacts, ok := rawData["contacts"]; ok {
+	if token, ok := rawData[tokenField]; ok {
+		err = bencode.DecodeBytes(token, &r.Token)
+		if err != nil {
+			return err
+		}
+		delete(rawData, tokenField) // it doesnt mess up findValue key finding below
+	}
+
+	if contacts, ok := rawData[contactsField]; ok {
 		err = bencode.DecodeBytes(contacts, &r.FindNodeData)
 		if err != nil {
 			return err
@@ -312,14 +356,13 @@ func (r *Response) UnmarshalBencode(b []byte) error {
 			break
 		}
 	}
-	}
 
 	return nil
 }
 
 type Error struct {
 	ID            messageID
-	NodeID        bitmap
+	NodeID        Bitmap
 	ExceptionType string
 	Response      []string
 }
@@ -337,7 +380,7 @@ func (e Error) MarshalBencode() ([]byte, error) {
 func (e *Error) UnmarshalBencode(b []byte) error {
 	var raw struct {
 		ID            messageID   `bencode:"1"`
-		NodeID        bitmap      `bencode:"2"`
+		NodeID        Bitmap      `bencode:"2"`
 		ExceptionType string      `bencode:"3"`
 		Args          interface{} `bencode:"4"`
 	}

dht/node_finder.go

@@ -13,7 +13,7 @@ import (
 
 type nodeFinder struct {
 	findValue bool // true if we're using findValue
-	target    bitmap
+	target    Bitmap
 	dht       *DHT
 
 	done *stopOnce.Stopper
@@ -26,7 +26,10 @@ type nodeFinder struct {
 
 	shortlistMutex *sync.Mutex
 	shortlist      []Node
-	shortlistAdded map[bitmap]bool
+	shortlistAdded map[Bitmap]bool
+
+	outstandingRequestsMutex *sync.RWMutex
+	outstandingRequests      uint
 }
 
 type findNodeResponse struct {
@@ -34,7 +37,7 @@ type findNodeResponse struct {
 	Nodes []Node
 }
 
-func newNodeFinder(dht *DHT, target bitmap, findValue bool) *nodeFinder {
+func newNodeFinder(dht *DHT, target Bitmap, findValue bool) *nodeFinder {
 	return &nodeFinder{
 		dht:              dht,
 		target:           target,
@@ -42,13 +45,18 @@ func newNodeFinder(dht *DHT, target bitmap, findValue bool) *nodeFinder {
 		findValueMutex:   &sync.Mutex{},
 		activeNodesMutex: &sync.Mutex{},
 		shortlistMutex:   &sync.Mutex{},
-		shortlistAdded:   make(map[bitmap]bool),
+		shortlistAdded:   make(map[Bitmap]bool),
 		done:             stopOnce.New(),
+		outstandingRequestsMutex: &sync.RWMutex{},
 	}
 }
 
 func (nf *nodeFinder) Find() (findNodeResponse, error) {
-	log.Debugf("[%s] starting an iterative Find() for %s (findValue is %t)", nf.dht.node.id.HexShort(), nf.target.HexShort(), nf.findValue)
+	if nf.findValue {
+		log.Debugf("[%s] starting an iterative Find for the value %s", nf.dht.node.id.HexShort(), nf.target.HexShort())
+	} else {
+		log.Debugf("[%s] starting an iterative Find for nodes near %s", nf.dht.node.id.HexShort(), nf.target.HexShort())
+	}
 	nf.appendNewToShortlist(nf.dht.rt.GetClosest(nf.target, alpha))
 	if len(nf.shortlist) == 0 {
 		return findNodeResponse{}, errors.Err("no nodes in routing table")
@@ -67,7 +75,7 @@ func (nf *nodeFinder) Find() (findNodeResponse, error) {
 	wg.Wait()
 
 	// TODO: what to do if we have less than K active nodes, shortlist is empty, but we
-	// TODO: have other nodes in our routing table whom we have not contacted. prolly contact them?
+	// TODO: have other nodes in our routing table whom we have not contacted. prolly contact them
 
 	result := findNodeResponse{}
 	if nf.findValue && len(nf.findValueResult) > 0 {
@@ -91,8 +99,8 @@ func (nf *nodeFinder) iterationWorker(num int) {
 		maybeNode := nf.popFromShortlist()
 		if maybeNode == nil {
 			// TODO: block if there are pending requests out from other workers. there may be more shortlist values coming
-			log.Debugf("[%s] no more nodes in shortlist", nf.dht.node.id.HexShort())
+			log.Debugf("[%s] worker %d: no nodes in shortlist, waiting...", nf.dht.node.id.HexShort(), num)
-			time.Sleep(10 * time.Millisecond)
+			time.Sleep(100 * time.Millisecond)
 		} else {
 			node := *maybeNode
 
@@ -107,7 +115,9 @@ func (nf *nodeFinder) iterationWorker(num int) {
 				req.Method = findNodeMethod
 			}
 
-			log.Debugf("[%s] contacting %s", nf.dht.node.id.HexShort(), node.id.HexShort())
+			log.Debugf("[%s] worker %d: contacting %s", nf.dht.node.id.HexShort(), num, node.id.HexShort())
+
+			nf.incrementOutstanding()
 
 			var res *Response
 			ctx, cancel := context.WithCancel(context.Background())
@@ -122,6 +132,7 @@ func (nf *nodeFinder) iterationWorker(num int) {
 
 			if res == nil {
 				// nothing to do, response timed out
+				log.Debugf("[%s] worker %d: timed out waiting for %s", nf.dht.node.id.HexShort(), num, node.id.HexShort())
 			} else if nf.findValue && res.FindValueKey != "" {
 				log.Debugf("[%s] worker %d: got value", nf.dht.node.id.HexShort(), num)
 				nf.findValueMutex.Lock()
@@ -130,10 +141,12 @@ func (nf *nodeFinder) iterationWorker(num int) {
 				nf.done.Stop()
 				return
 			} else {
-				log.Debugf("[%s] worker %d: got more contacts", nf.dht.node.id.HexShort(), num)
+				log.Debugf("[%s] worker %d: got contacts", nf.dht.node.id.HexShort(), num)
 				nf.insertIntoActiveList(node)
 				nf.appendNewToShortlist(res.FindNodeData)
 			}
+
+			nf.decrementOutstanding() // this is all the way down here because we need to add to shortlist first
 		}
 
 		if nf.isSearchFinished() {
@@ -199,6 +212,7 @@ func (nf *nodeFinder) isSearchFinished() bool {
 	default:
 	}
 
+	if !nf.areRequestsOutstanding() {
 		nf.shortlistMutex.Lock()
 		defer nf.shortlistMutex.Unlock()
 
@@ -213,6 +227,25 @@ func (nf *nodeFinder) isSearchFinished() bool {
 			// we have at least K active nodes, and we don't have any closer nodes yet to contact
 			return true
 		}
+	}
 
 	return false
 }
+
+func (nf *nodeFinder) incrementOutstanding() {
+	nf.outstandingRequestsMutex.Lock()
+	defer nf.outstandingRequestsMutex.Unlock()
+	nf.outstandingRequests++
+}
+func (nf *nodeFinder) decrementOutstanding() {
+	nf.outstandingRequestsMutex.Lock()
+	defer nf.outstandingRequestsMutex.Unlock()
+	if nf.outstandingRequests > 0 {
+		nf.outstandingRequests--
+	}
+}
+func (nf *nodeFinder) areRequestsOutstanding() bool {
+	nf.outstandingRequestsMutex.RLock()
+	defer nf.outstandingRequestsMutex.RUnlock()
+	return nf.outstandingRequests > 0
+}

dht/routing_table.go

@@ -15,9 +15,14 @@ import (
 )
 
 type Node struct {
-	id   bitmap
+	id    Bitmap
 	ip    net.IP
 	port  int
+	token string // this is set when the node is returned from a FindNode call
+}
+
+func (n Node) String() string {
+	return n.id.HexShort() + "@" + n.Addr().String()
 }
 
 func (n Node) Addr() *net.UDPAddr {
@@ -51,7 +56,7 @@ func (n *Node) UnmarshalCompact(b []byte) error {
 	}
 	n.ip = net.IPv4(b[0], b[1], b[2], b[3]).To4()
 	n.port = int(uint16(b[5]) | uint16(b[4])<<8)
-	n.id = newBitmapFromBytes(b[6:])
+	n.id = BitmapFromBytesP(b[6:])
 	return nil
 }
 
@@ -95,7 +100,7 @@ func (n *Node) UnmarshalBencode(b []byte) error {
 
 type sortedNode struct {
 	node                Node
-	xorDistanceToTarget bitmap
+	xorDistanceToTarget Bitmap
 }
 
 type byXorDistance []sortedNode
@@ -128,6 +133,18 @@ func (rt *routingTable) BucketInfo() string {
 
 	bucketInfo := []string{}
 	for i, b := range rt.buckets {
+		contents := bucketContents(b)
+		if contents != "" {
+			bucketInfo = append(bucketInfo, fmt.Sprintf("Bucket %d: %s", i, contents))
+		}
+	}
+	if len(bucketInfo) == 0 {
+		return "buckets are empty"
+	}
+	return strings.Join(bucketInfo, "\n")
+}
+
+func bucketContents(b *list.List) string {
 	count := 0
 	ids := ""
 	for curr := b.Front(); curr != nil; curr = curr.Next() {
@@ -139,14 +156,11 @@ func (rt *routingTable) BucketInfo() string {
 	}
 
 	if count > 0 {
-			bucketInfo = append(bucketInfo, fmt.Sprintf("Bucket %d: (%d) %s", i, count, ids))
+		return fmt.Sprintf("(%d) %s", count, ids)
+	} else {
+		return ""
 	}
 }
-	if len(bucketInfo) == 0 {
-		return "buckets are empty"
-	}
-	return strings.Join(bucketInfo, "\n")
-}
 
 func (rt *routingTable) Update(node Node) {
 	rt.lock.Lock()
@@ -165,7 +179,7 @@ func (rt *routingTable) Update(node Node) {
 	}
 }
 
-func (rt *routingTable) RemoveByID(id bitmap) {
+func (rt *routingTable) RemoveByID(id Bitmap) {
 	rt.lock.Lock()
 	defer rt.lock.Unlock()
 	bucketNum := bucketFor(rt.node.id, id)
@@ -176,7 +190,7 @@ func (rt *routingTable) RemoveByID(id bitmap) {
 	}
 }
 
-func (rt *routingTable) GetClosest(target bitmap, limit int) []Node {
+func (rt *routingTable) GetClosest(target Bitmap, limit int) []Node {
 	rt.lock.RLock()
 	defer rt.lock.RUnlock()
 
@@ -216,7 +230,7 @@ func (rt *routingTable) GetClosest(target bitmap, limit int) []Node {
 	return nodes
 }
 
-func findInList(bucket *list.List, value bitmap) *list.Element {
+func findInList(bucket *list.List, value Bitmap) *list.Element {
 	for curr := bucket.Front(); curr != nil; curr = curr.Next() {
 		if curr.Value.(Node).id.Equals(value) {
 			return curr
@@ -225,7 +239,7 @@ func findInList(bucket *list.List, value bitmap) *list.Element {
 	return nil
 }
 
-func appendNodes(nodes []sortedNode, start *list.Element, target bitmap) []sortedNode {
+func appendNodes(nodes []sortedNode, start *list.Element, target Bitmap) []sortedNode {
 	for curr := start; curr != nil; curr = curr.Next() {
 		node := curr.Value.(Node)
 		nodes = append(nodes, sortedNode{node, node.id.Xor(target)})
@@ -233,14 +247,14 @@ func appendNodes(nodes []sortedNode, start *list.Element, target bitmap) []sorte
 	return nodes
 }
 
-func bucketFor(id bitmap, target bitmap) int {
+func bucketFor(id Bitmap, target Bitmap) int {
 	if id.Equals(target) {
 		panic("nodes do not have a bucket for themselves")
 	}
 	return numBuckets - 1 - target.Xor(id).PrefixLen()
 }
 
-func sortNodesInPlace(nodes []Node, target bitmap) {
+func sortNodesInPlace(nodes []Node, target Bitmap) {
 	toSort := make([]sortedNode, len(nodes))
 
 	for i, n := range nodes {

dht/routing_table_test.go

@@ -7,21 +7,21 @@ import (
 )
 
 func TestRoutingTable_bucketFor(t *testing.T) {
-	target := newBitmapFromHex("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000")
+	target := BitmapFromHexP("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000")
 	var tests = []struct {
-		id       bitmap
+		id       Bitmap
-		target   bitmap
+		target   Bitmap
 		expected int
 	}{
-		{newBitmapFromHex("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001"), target, 0},
+		{BitmapFromHexP("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001"), target, 0},
-		{newBitmapFromHex("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002"), target, 1},
+		{BitmapFromHexP("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002"), target, 1},
-		{newBitmapFromHex("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003"), target, 1},
+		{BitmapFromHexP("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003"), target, 1},
-		{newBitmapFromHex("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000004"), target, 2},
+		{BitmapFromHexP("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000004"), target, 2},
-		{newBitmapFromHex("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005"), target, 2},
+		{BitmapFromHexP("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005"), target, 2},
-		{newBitmapFromHex("00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000f"), target, 3},
+		{BitmapFromHexP("00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000f"), target, 3},
-		{newBitmapFromHex("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010"), target, 4},
+		{BitmapFromHexP("000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010"), target, 4},
-		{newBitmapFromHex("F00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), target, 383},
+		{BitmapFromHexP("F00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), target, 383},
-		{newBitmapFromHex("F0000000000000000000000000000000F0000000000000000000000000F0000000000000000000000000000000000000"), target, 383},
+		{BitmapFromHexP("F0000000000000000000000000000000F0000000000000000000000000F0000000000000000000000000000000000000"), target, 383},
 	}
 
 	for _, tt := range tests {
@@ -33,14 +33,14 @@ func TestRoutingTable_bucketFor(t *testing.T) {
 }
 
 func TestRoutingTable(t *testing.T) {
-	n1 := newBitmapFromHex("FFFFFFFF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000")
+	n1 := BitmapFromHexP("FFFFFFFF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000")
-	n2 := newBitmapFromHex("FFFFFFF00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000")
+	n2 := BitmapFromHexP("FFFFFFF00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000")
-	n3 := newBitmapFromHex("111111110000000000000000000000000000000000000000000000000000000000000000000000000000000000000000")
+	n3 := BitmapFromHexP("111111110000000000000000000000000000000000000000000000000000000000000000000000000000000000000000")
-	rt := newRoutingTable(&Node{n1, net.ParseIP("127.0.0.1"), 8000})
+	rt := newRoutingTable(&Node{n1, net.ParseIP("127.0.0.1"), 8000, ""})
-	rt.Update(Node{n2, net.ParseIP("127.0.0.1"), 8001})
+	rt.Update(Node{n2, net.ParseIP("127.0.0.1"), 8001, ""})
-	rt.Update(Node{n3, net.ParseIP("127.0.0.1"), 8002})
+	rt.Update(Node{n3, net.ParseIP("127.0.0.1"), 8002, ""})
 
-	contacts := rt.GetClosest(newBitmapFromHex("222222220000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), 1)
+	contacts := rt.GetClosest(BitmapFromHexP("222222220000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), 1)
 	if len(contacts) != 1 {
 		t.Fail()
 		return
@@ -64,7 +64,7 @@ func TestRoutingTable(t *testing.T) {
 
 func TestCompactEncoding(t *testing.T) {
 	n := Node{
-		id:   newBitmapFromHex("1c8aff71b99462464d9eeac639595ab99664be3482cb91a29d87467515c7d9158fe72aa1f1582dab07d8f8b5db277f41"),
+		id:   BitmapFromHexP("1c8aff71b99462464d9eeac639595ab99664be3482cb91a29d87467515c7d9158fe72aa1f1582dab07d8f8b5db277f41"),
 		ip:   net.ParseIP("1.2.3.4"),
 		port: int(55<<8 + 66),
 	}

dht/rpc.go

@@ -15,7 +15,7 @@ import (
 
 // handlePacket handles packets received from udp.
 func handlePacket(dht *DHT, pkt packet) {
-	//log.Debugf("[%s] Received message from %s:%s (%d bytes) %s", dht.node.id.HexShort(), pkt.raddr.IP.String(), strconv.Itoa(pkt.raddr.Port), len(pkt.data), hex.EncodeToString(pkt.data))
+	//log.Debugf("[%s] Received message from %s (%d bytes) %s", dht.node.id.HexShort(), pkt.raddr.String(), len(pkt.data), hex.EncodeToString(pkt.data))
 
 	if !util.InSlice(string(pkt.data[0:5]), []string{"d1:0i", "di0ei"}) {
 		log.Errorf("[%s] data is not a well-formatted dict: (%d bytes) %s", dht.node.id.HexShort(), len(pkt.data), hex.EncodeToString(pkt.data))
@@ -32,7 +32,7 @@ func handlePacket(dht *DHT, pkt packet) {
 		request := Request{}
 		err := bencode.DecodeBytes(pkt.data, &request)
 		if err != nil {
-			log.Errorf("[%s] error decoding request: %s: (%d bytes) %s", dht.node.id.HexShort(), err.Error(), len(pkt.data), hex.EncodeToString(pkt.data))
+			log.Errorf("[%s] error decoding request from %s: %s: (%d bytes) %s", dht.node.id.HexShort(), pkt.raddr.String(), err.Error(), len(pkt.data), hex.EncodeToString(pkt.data))
 			return
 		}
 		log.Debugf("[%s] query %s: received request from %s: %s(%s)", dht.node.id.HexShort(), request.ID.HexShort(), request.NodeID.HexShort(), request.Method, request.ArgsDebug())
@@ -42,7 +42,7 @@ func handlePacket(dht *DHT, pkt packet) {
 		response := Response{}
 		err := bencode.DecodeBytes(pkt.data, &response)
 		if err != nil {
-			log.Errorf("[%s] error decoding response: %s: (%d bytes) %s", dht.node.id.HexShort(), err.Error(), len(pkt.data), hex.EncodeToString(pkt.data))
+			log.Errorf("[%s] error decoding response from %s: %s: (%d bytes) %s", dht.node.id.HexShort(), pkt.raddr.String(), err.Error(), len(pkt.data), hex.EncodeToString(pkt.data))
 			return
 		}
 		log.Debugf("[%s] query %s: received response from %s: %s", dht.node.id.HexShort(), response.ID.HexShort(), response.NodeID.HexShort(), response.ArgsDebug())
@@ -52,7 +52,7 @@ func handlePacket(dht *DHT, pkt packet) {
 		e := Error{}
 		err := bencode.DecodeBytes(pkt.data, &e)
 		if err != nil {
-			log.Errorf("[%s] error decoding error: %s: (%d bytes) %s", dht.node.id.HexShort(), err.Error(), len(pkt.data), hex.EncodeToString(pkt.data))
+			log.Errorf("[%s] error decoding error from %s: %s: (%d bytes) %s", dht.node.id.HexShort(), pkt.raddr.String(), err.Error(), len(pkt.data), hex.EncodeToString(pkt.data))
 			return
 		}
 		log.Debugf("[%s] query %s: received error from %s: %s", dht.node.id.HexShort(), e.ID.HexShort(), e.NodeID.HexShort(), e.ExceptionType)
@@ -72,19 +72,28 @@ func handleRequest(dht *DHT, addr *net.UDPAddr, request Request) {
 	}
 
 	switch request.Method {
+	default:
+		//		send(dht, addr, makeError(t, protocolError, "invalid q"))
+		log.Errorln("invalid request method")
+		return
 	case pingMethod:
 		send(dht, addr, Response{ID: request.ID, NodeID: dht.node.id, Data: pingSuccessResponse})
 	case storeMethod:
 		// TODO: we should be sending the IP in the request, not just using the sender's IP
 		// TODO: should we be using StoreArgs.NodeID or StoreArgs.Value.LbryID ???
+		if dht.tokens.Verify(request.StoreArgs.Value.Token, request.NodeID, addr) {
 			dht.store.Upsert(request.StoreArgs.BlobHash, Node{id: request.StoreArgs.NodeID, ip: addr.IP, port: request.StoreArgs.Value.Port})
 			send(dht, addr, Response{ID: request.ID, NodeID: dht.node.id, Data: storeSuccessResponse})
+		} else {
+			send(dht, addr, Error{ID: request.ID, NodeID: dht.node.id, ExceptionType: "invalid-token"})
+		}
 	case findNodeMethod:
 		if request.Arg == nil {
 			log.Errorln("request is missing arg")
 			return
 		}
-		doFindNodes(dht, addr, request)
+		send(dht, addr, getFindResponse(dht, request))
+
 	case findValueMethod:
 		if request.Arg == nil {
 			log.Errorln("request is missing arg")
@@ -97,32 +106,30 @@ func handleRequest(dht *DHT, addr *net.UDPAddr, request Request) {
 				NodeID:       dht.node.id,
 				FindValueKey: request.Arg.RawString(),
 				FindNodeData: nodes,
+				Token:        dht.tokens.Get(request.NodeID, addr),
 			})
 		} else {
-			doFindNodes(dht, addr, request)
+			res := getFindResponse(dht, request)
+			res.Token = dht.tokens.Get(request.NodeID, addr)
+			send(dht, addr, res)
 		}
-
-	default:
-		//		send(dht, addr, makeError(t, protocolError, "invalid q"))
-		log.Errorln("invalid request method")
-		return
 	}
 
 	node := Node{id: request.NodeID, ip: addr.IP, port: addr.Port}
 	dht.rt.Update(node)
 }
 
-func doFindNodes(dht *DHT, addr *net.UDPAddr, request Request) {
+func getFindResponse(dht *DHT, request Request) Response {
 	closestNodes := dht.rt.GetClosest(*request.Arg, bucketSize)
-	if len(closestNodes) > 0 {
+	response := Response{
-		response := Response{ID: request.ID, NodeID: dht.node.id, FindNodeData: make([]Node, len(closestNodes))}
+		ID:           request.ID,
+		NodeID:       dht.node.id,
+		FindNodeData: make([]Node, len(closestNodes)),
+	}
 	for i, n := range closestNodes {
 		response.FindNodeData[i] = n
 	}
-		send(dht, addr, response)
+	return response
-	} else {
-		log.Warn("no nodes in routing table")
-	}
 }
 
 // handleResponse handles responses received from udp.

dht/rpc_test.go

@@ -88,8 +88,8 @@ func (t *testUDPConn) Close() error {
 }
 
 func TestPing(t *testing.T) {
-	dhtNodeID := newRandomBitmap()
+	dhtNodeID := RandomBitmapP()
-	testNodeID := newRandomBitmap()
+	testNodeID := RandomBitmapP()
 
 	conn := newTestUDPConn("127.0.0.1:21217")
 
@@ -183,8 +183,8 @@ func TestPing(t *testing.T) {
 }
 
 func TestStore(t *testing.T) {
-	dhtNodeID := newRandomBitmap()
+	dhtNodeID := RandomBitmapP()
-	testNodeID := newRandomBitmap()
+	testNodeID := RandomBitmapP()
 
 	conn := newTestUDPConn("127.0.0.1:21217")
 
@@ -199,7 +199,7 @@ func TestStore(t *testing.T) {
 	defer dht.Shutdown()
 
 	messageID := newMessageID()
-	blobHashToStore := newRandomBitmap()
+	blobHashToStore := RandomBitmapP()
 
 	storeRequest := Request{
 		ID:     messageID,
@@ -208,7 +208,7 @@ func TestStore(t *testing.T) {
 		StoreArgs: &storeArgs{
 			BlobHash: blobHashToStore,
 			Value: storeArgsValue{
-				Token:  "arst",
+				Token:  dht.tokens.Get(testNodeID, conn.addr),
 				LbryID: testNodeID,
 				Port:   9999,
 			},
@@ -280,8 +280,8 @@ func TestStore(t *testing.T) {
 }
 
 func TestFindNode(t *testing.T) {
-	dhtNodeID := newRandomBitmap()
+	dhtNodeID := RandomBitmapP()
-	testNodeID := newRandomBitmap()
+	testNodeID := RandomBitmapP()
 
 	conn := newTestUDPConn("127.0.0.1:21217")
 
@@ -297,13 +297,13 @@ func TestFindNode(t *testing.T) {
 	nodesToInsert := 3
 	var nodes []Node
 	for i := 0; i < nodesToInsert; i++ {
-		n := Node{id: newRandomBitmap(), ip: net.ParseIP("127.0.0.1"), port: 10000 + i}
+		n := Node{id: RandomBitmapP(), ip: net.ParseIP("127.0.0.1"), port: 10000 + i}
 		nodes = append(nodes, n)
 		dht.rt.Update(n)
 	}
 
 	messageID := newMessageID()
-	blobHashToFind := newRandomBitmap()
+	blobHashToFind := RandomBitmapP()
 
 	request := Request{
 		ID:     messageID,
@@ -338,27 +338,17 @@ func TestFindNode(t *testing.T) {
 		t.Fatal("missing payload field")
 	}
 
-	payload, ok := response[headerPayloadField].(map[string]interface{})
+	contacts, ok := response[headerPayloadField].([]interface{})
 	if !ok {
-		t.Fatal("payload is not a dictionary")
+		t.Fatal("payload is not a list")
-	}
-
-	contactsList, ok := payload["contacts"]
-	if !ok {
-		t.Fatal("payload is missing 'contacts' key")
-	}
-
-	contacts, ok := contactsList.([]interface{})
-	if !ok {
-		t.Fatal("'contacts' is not a list")
 	}
 
 	verifyContacts(t, contacts, nodes)
 }
 
 func TestFindValueExisting(t *testing.T) {
-	dhtNodeID := newRandomBitmap()
+	dhtNodeID := RandomBitmapP()
-	testNodeID := newRandomBitmap()
+	testNodeID := RandomBitmapP()
 
 	conn := newTestUDPConn("127.0.0.1:21217")
 
@@ -375,7 +365,7 @@ func TestFindValueExisting(t *testing.T) {
 	nodesToInsert := 3
 	var nodes []Node
 	for i := 0; i < nodesToInsert; i++ {
-		n := Node{id: newRandomBitmap(), ip: net.ParseIP("127.0.0.1"), port: 10000 + i}
+		n := Node{id: RandomBitmapP(), ip: net.ParseIP("127.0.0.1"), port: 10000 + i}
 		nodes = append(nodes, n)
 		dht.rt.Update(n)
 	}
@@ -383,9 +373,9 @@ func TestFindValueExisting(t *testing.T) {
 	//data, _ := hex.DecodeString("64313a30693065313a3132303a7de8e57d34e316abbb5a8a8da50dcd1ad4c80e0f313a3234383a7ce1b831dec8689e44f80f547d2dea171f6a625e1a4ff6c6165e645f953103dabeb068a622203f859c6c64658fd3aa3b313a33393a66696e6456616c7565313a346c34383aa47624b8e7ee1e54df0c45e2eb858feb0b705bd2a78d8b739be31ba188f4bd6f56b371c51fecc5280d5fd26ba4168e966565")
 
 	messageID := newMessageID()
-	valueToFind := newRandomBitmap()
+	valueToFind := RandomBitmapP()
 
-	nodeToFind := Node{id: newRandomBitmap(), ip: net.ParseIP("1.2.3.4"), port: 1286}
+	nodeToFind := Node{id: RandomBitmapP(), ip: net.ParseIP("1.2.3.4"), port: 1286}
 	dht.store.Upsert(valueToFind, nodeToFind)
 	dht.store.Upsert(valueToFind, nodeToFind)
 	dht.store.Upsert(valueToFind, nodeToFind)
@@ -442,8 +432,8 @@ func TestFindValueExisting(t *testing.T) {
 }
 
 func TestFindValueFallbackToFindNode(t *testing.T) {
-	dhtNodeID := newRandomBitmap()
+	dhtNodeID := RandomBitmapP()
-	testNodeID := newRandomBitmap()
+	testNodeID := RandomBitmapP()
 
 	conn := newTestUDPConn("127.0.0.1:21217")
 
@@ -460,13 +450,13 @@ func TestFindValueFallbackToFindNode(t *testing.T) {
 	nodesToInsert := 3
 	var nodes []Node
 	for i := 0; i < nodesToInsert; i++ {
-		n := Node{id: newRandomBitmap(), ip: net.ParseIP("127.0.0.1"), port: 10000 + i}
+		n := Node{id: RandomBitmapP(), ip: net.ParseIP("127.0.0.1"), port: 10000 + i}
 		nodes = append(nodes, n)
 		dht.rt.Update(n)
 	}
 
 	messageID := newMessageID()
-	valueToFind := newRandomBitmap()
+	valueToFind := RandomBitmapP()
 
 	request := Request{
 		ID:     messageID,
@@ -506,7 +496,7 @@ func TestFindValueFallbackToFindNode(t *testing.T) {
 		t.Fatal("payload is not a dictionary")
 	}
 
-	contactsList, ok := payload["contacts"]
+	contactsList, ok := payload[contactsField]
 	if !ok {
 		t.Fatal("payload is missing 'contacts' key")
 	}

dht/store.go

@@ -11,30 +11,30 @@ type peer struct {
 
 type peerStore struct {
 	// map of blob hashes to (map of node IDs to bools)
-	hashes map[bitmap]map[bitmap]bool
+	hashes map[Bitmap]map[Bitmap]bool
 	// map of node IDs to peers
-	nodeInfo map[bitmap]peer
+	nodeInfo map[Bitmap]peer
 	lock     sync.RWMutex
 }
 
 func newPeerStore() *peerStore {
 	return &peerStore{
-		hashes:   make(map[bitmap]map[bitmap]bool),
+		hashes:   make(map[Bitmap]map[Bitmap]bool),
-		nodeInfo: make(map[bitmap]peer),
+		nodeInfo: make(map[Bitmap]peer),
 	}
 }
 
-func (s *peerStore) Upsert(blobHash bitmap, node Node) {
+func (s *peerStore) Upsert(blobHash Bitmap, node Node) {
 	s.lock.Lock()
 	defer s.lock.Unlock()
 	if _, ok := s.hashes[blobHash]; !ok {
-		s.hashes[blobHash] = make(map[bitmap]bool)
+		s.hashes[blobHash] = make(map[Bitmap]bool)
 	}
 	s.hashes[blobHash][node.id] = true
 	s.nodeInfo[node.id] = peer{node: node}
 }
 
-func (s *peerStore) Get(blobHash bitmap) []Node {
+func (s *peerStore) Get(blobHash Bitmap) []Node {
 	s.lock.RLock()
 	defer s.lock.RUnlock()
 	var nodes []Node

dht/token_manager.go

@@ -0,0 +1,80 @@
+package dht
+
+import (
+	"bytes"
+	"crypto/rand"
+	"crypto/sha256"
+	"net"
+	"strconv"
+	"sync"
+	"time"
+
+	"github.com/lbryio/lbry.go/stopOnce"
+)
+
+type tokenManager struct {
+	secret     []byte
+	prevSecret []byte
+	lock       *sync.RWMutex
+	wg         *sync.WaitGroup
+	done       *stopOnce.Stopper
+}
+
+func (tm *tokenManager) Start(interval time.Duration) {
+	tm.secret = make([]byte, 64)
+	tm.prevSecret = make([]byte, 64)
+	tm.lock = &sync.RWMutex{}
+	tm.wg = &sync.WaitGroup{}
+	tm.done = stopOnce.New()
+
+	tm.rotateSecret()
+
+	tm.wg.Add(1)
+	go func() {
+		defer tm.wg.Done()
+		tick := time.NewTicker(interval)
+		for {
+			select {
+			case <-tick.C:
+				tm.rotateSecret()
+			case <-tm.done.Chan():
+				return
+			}
+		}
+	}()
+}
+
+func (tm *tokenManager) Stop() {
+	tm.done.Stop()
+	tm.wg.Wait()
+}
+
+func (tm *tokenManager) Get(nodeID Bitmap, addr *net.UDPAddr) string {
+	return genToken(tm.secret, nodeID, addr)
+}
+
+func (tm *tokenManager) Verify(token string, nodeID Bitmap, addr *net.UDPAddr) bool {
+	return token == genToken(tm.secret, nodeID, addr) || token == genToken(tm.prevSecret, nodeID, addr)
+}
+
+func genToken(secret []byte, nodeID Bitmap, addr *net.UDPAddr) string {
+	buf := bytes.Buffer{}
+	buf.Write(nodeID[:])
+	buf.Write(addr.IP)
+	buf.WriteString(strconv.Itoa(addr.Port))
+	buf.Write(secret)
+	t := sha256.Sum256(buf.Bytes())
+	return string(t[:])
+}
+
+func (tm *tokenManager) rotateSecret() {
+	tm.lock.Lock()
+	defer tm.lock.Unlock()
+
+	copy(tm.prevSecret, tm.secret)
+
+	_, err := rand.Read(tm.secret)
+	if err != nil {
+		panic(err)
+	}
+}