whisper: topics replaced by bloom filters

2 files changed, 35 insertions, 29 deletions

diff --git a/whisper/mailserver/mailserver.go b/whisper/mailserver/mailserver.go
index a889c2bd2..57e6505ad 100644
--- a/whisper/mailserver/mailserver.go
+++ b/whisper/mailserver/mailserver.go
@@ -107,17 +107,16 @@ func (s *WMailServer) DeliverMail(peer *whisper.Peer, request *whisper.Envelope)
 		return
 	}
 
-	ok, lower, upper, topic := s.validateRequest(peer.ID(), request)
+	ok, lower, upper, bloom := s.validateRequest(peer.ID(), request)
 	if ok {
-		s.processRequest(peer, lower, upper, topic)
+		s.processRequest(peer, lower, upper, bloom)
 	}
 }
 
-func (s *WMailServer) processRequest(peer *whisper.Peer, lower, upper uint32, topic whisper.TopicType) []*whisper.Envelope {
+func (s *WMailServer) processRequest(peer *whisper.Peer, lower, upper uint32, bloom []byte) []*whisper.Envelope {
 	ret := make([]*whisper.Envelope, 0)
 	var err error
 	var zero common.Hash
-	var empty whisper.TopicType
 	kl := NewDbKey(lower, zero)
 	ku := NewDbKey(upper, zero)
 	i := s.db.NewIterator(&util.Range{Start: kl.raw, Limit: ku.raw}, nil)
@@ -130,7 +129,7 @@ func (s *WMailServer) processRequest(peer *whisper.Peer, lower, upper uint32, to
 			log.Error(fmt.Sprintf("RLP decoding failed: %s", err))
 		}
 
-		if topic == empty || envelope.Topic == topic {
+		if whisper.BloomFilterMatch(bloom, envelope.Bloom()) {
 			if peer == nil {
 				// used for test purposes
 				ret = append(ret, &envelope)
@@ -152,22 +151,16 @@ func (s *WMailServer) processRequest(peer *whisper.Peer, lower, upper uint32, to
 	return ret
 }
 
-func (s *WMailServer) validateRequest(peerID []byte, request *whisper.Envelope) (bool, uint32, uint32, whisper.TopicType) {
-	var topic whisper.TopicType
+func (s *WMailServer) validateRequest(peerID []byte, request *whisper.Envelope) (bool, uint32, uint32, []byte) {
 	if s.pow > 0.0 && request.PoW() < s.pow {
-		return false, 0, 0, topic
+		return false, 0, 0, nil
 	}
 
 	f := whisper.Filter{KeySym: s.key}
 	decrypted := request.Open(&f)
 	if decrypted == nil {
 		log.Warn(fmt.Sprintf("Failed to decrypt p2p request"))
-		return false, 0, 0, topic
-	}
-
-	if len(decrypted.Payload) < 8 {
-		log.Warn(fmt.Sprintf("Undersized p2p request"))
-		return false, 0, 0, topic
+		return false, 0, 0, nil
 	}
 
 	src := crypto.FromECDSAPub(decrypted.Src)
@@ -179,15 +172,24 @@ func (s *WMailServer) validateRequest(peerID []byte, request *whisper.Envelope)
 	// if !bytes.Equal(peerID, src) {
 	if src == nil {
 		log.Warn(fmt.Sprintf("Wrong signature of p2p request"))
-		return false, 0, 0, topic
+		return false, 0, 0, nil
 	}
 
-	lower := binary.BigEndian.Uint32(decrypted.Payload[:4])
-	upper := binary.BigEndian.Uint32(decrypted.Payload[4:8])
-
-	if len(decrypted.Payload) >= 8+whisper.TopicLength {
-		topic = whisper.BytesToTopic(decrypted.Payload[8:])
+	var bloom []byte
+	payloadSize := len(decrypted.Payload)
+	if payloadSize < 8 {
+		log.Warn(fmt.Sprintf("Undersized p2p request"))
+		return false, 0, 0, nil
+	} else if payloadSize == 8 {
+		bloom = whisper.MakeFullNodeBloom()
+	} else if payloadSize < 8+whisper.BloomFilterSize {
+		log.Warn(fmt.Sprintf("Undersized bloom filter in p2p request"))
+		return false, 0, 0, nil
+	} else {
+		bloom = decrypted.Payload[8 : 8+whisper.BloomFilterSize]
 	}
 
-	return true, lower, upper, topic
+	lower := binary.BigEndian.Uint32(decrypted.Payload[:4])
+	upper := binary.BigEndian.Uint32(decrypted.Payload[4:8])
+	return true, lower, upper, bloom
 }
diff --git a/whisper/mailserver/server_test.go b/whisper/mailserver/server_test.go
index 63864c1e6..d5b993afb 100644
--- a/whisper/mailserver/server_test.go
+++ b/whisper/mailserver/server_test.go
@@ -17,6 +17,7 @@
 package mailserver
 
 import (
+	"bytes"
 	"crypto/ecdsa"
 	"encoding/binary"
 	"io/ioutil"
@@ -61,7 +62,7 @@ func generateEnvelope(t *testing.T) *whisper.Envelope {
 	h := crypto.Keccak256Hash([]byte("test sample data"))
 	params := &whisper.MessageParams{
 		KeySym:   h[:],
-		Topic:    whisper.TopicType{},
+		Topic:    whisper.TopicType{0x1F, 0x7E, 0xA1, 0x7F},
 		Payload:  []byte("test payload"),
 		PoW:      powRequirement,
 		WorkTime: 2,
@@ -121,6 +122,7 @@ func deliverTest(t *testing.T, server *WMailServer, env *whisper.Envelope) {
 		upp:   birth + 1,
 		key:   testPeerID,
 	}
+
 	singleRequest(t, server, env, p, true)
 
 	p.low, p.upp = birth+1, 0xffffffff
@@ -131,14 +133,14 @@ func deliverTest(t *testing.T, server *WMailServer, env *whisper.Envelope) {
 
 	p.low = birth - 1
 	p.upp = birth + 1
-	p.topic[0]++
+	p.topic[0] = 0xFF
 	singleRequest(t, server, env, p, false)
 }
 
 func singleRequest(t *testing.T, server *WMailServer, env *whisper.Envelope, p *ServerTestParams, expect bool) {
 	request := createRequest(t, p)
 	src := crypto.FromECDSAPub(&p.key.PublicKey)
-	ok, lower, upper, topic := server.validateRequest(src, request)
+	ok, lower, upper, bloom := server.validateRequest(src, request)
 	if !ok {
 		t.Fatalf("request validation failed, seed: %d.", seed)
 	}
@@ -148,12 +150,13 @@ func singleRequest(t *testing.T, server *WMailServer, env *whisper.Envelope, p *
 	if upper != p.upp {
 		t.Fatalf("request validation failed (upper bound), seed: %d.", seed)
 	}
-	if topic != p.topic {
+	expectedBloom := whisper.TopicToBloom(p.topic)
+	if !bytes.Equal(bloom, expectedBloom) {
 		t.Fatalf("request validation failed (topic), seed: %d.", seed)
 	}
 
 	var exist bool
-	mail := server.processRequest(nil, p.low, p.upp, p.topic)
+	mail := server.processRequest(nil, p.low, p.upp, bloom)
 	for _, msg := range mail {
 		if msg.Hash() == env.Hash() {
 			exist = true
@@ -166,7 +169,7 @@ func singleRequest(t *testing.T, server *WMailServer, env *whisper.Envelope, p *
 	}
 
 	src[0]++
-	ok, lower, upper, topic = server.validateRequest(src, request)
+	ok, lower, upper, bloom = server.validateRequest(src, request)
 	if !ok {
 		// request should be valid regardless of signature
 		t.Fatalf("request validation false negative, seed: %d (lower: %d, upper: %d).", seed, lower, upper)
@@ -174,10 +177,11 @@ func singleRequest(t *testing.T, server *WMailServer, env *whisper.Envelope, p *
 }
 
 func createRequest(t *testing.T, p *ServerTestParams) *whisper.Envelope {
-	data := make([]byte, 8+whisper.TopicLength)
+	bloom := whisper.TopicToBloom(p.topic)
+	data := make([]byte, 8)
 	binary.BigEndian.PutUint32(data, p.low)
 	binary.BigEndian.PutUint32(data[4:], p.upp)
-	copy(data[8:], p.topic[:])
+	data = append(data, bloom...)
 
 	key, err := shh.GetSymKey(keyID)
 	if err != nil {