whisper: made PoW and MaxMsgSize customizable

cmd/wnode/main.go

@@ -84,8 +84,8 @@ var (
 	argVerbosity = flag.Int("verbosity", int(log.LvlWarn), "log verbosity level")
 	argTTL       = flag.Uint("ttl", 30, "time-to-live for messages in seconds")
 	argWorkTime  = flag.Uint("work", 5, "work time in seconds")
-	argPoW       = flag.Float64("pow", whisper.MinimumPoW, "PoW for normal messages in float format (e.g. 2.7)")
+	argPoW       = flag.Float64("pow", whisper.DefaultMinimumPoW, "PoW for normal messages in float format (e.g. 2.7)")
-	argServerPoW = flag.Float64("mspow", whisper.MinimumPoW, "PoW requirement for Mail Server request")
+	argServerPoW = flag.Float64("mspow", whisper.DefaultMinimumPoW, "PoW requirement for Mail Server request")
 
 	argIP     = flag.String("ip", "", "IP address and port of this node (e.g. 127.0.0.1:30303)")
 	argPub    = flag.String("pub", "", "public key for asymmetric encryption")

whisper/whisperv5/api.go

@@ -72,6 +72,20 @@ func (api *PublicWhisperAPI) Stats() (string, error) {
 	return api.whisper.Stats(), nil
 }
 
+func (api *PublicWhisperAPI) SetMaxMessageLength(val int) error {
+	if api.whisper == nil {
+		return whisperOffLineErr
+	}
+	return api.whisper.SetMaxMessageLength(val)
+}
+
+func (api *PublicWhisperAPI) SetMinimumPoW(val float64) error {
+	if api.whisper == nil {
+		return whisperOffLineErr
+	}
+	return api.whisper.SetMinimumPoW(val)
+}
+
 // MarkPeerTrusted marks specific peer trusted, which will allow it
 // to send historic (expired) messages.
 func (api *PublicWhisperAPI) MarkPeerTrusted(peerID hexutil.Bytes) error {
@@ -352,7 +366,7 @@ func (api *PublicWhisperAPI) Post(args PostArgs) error {
 		log.Error(fmt.Sprintf(err.Error()))
 		return err
 	}
-	if envelope.size() > MaxMessageLength {
+	if envelope.size() > api.whisper.maxMsgLength {
 		info := "Post: message is too big"
 		log.Error(fmt.Sprintf(info))
 		return errors.New(info)

whisper/whisperv5/api_test.go

@@ -323,7 +323,7 @@ func TestIntegrationAsym(t *testing.T) {
 	f.To = key
 	f.From = sig
 	f.Topics = topics[:]
-	f.PoW = MinimumPoW / 2
+	f.PoW = DefaultMinimumPoW / 2
 	f.AcceptP2P = true
 
 	id, err := api.NewFilter(f)
@@ -337,7 +337,7 @@ func TestIntegrationAsym(t *testing.T) {
 	p.To = f.To
 	p.Padding = []byte("test string")
 	p.Payload = []byte("extended test string")
-	p.PoW = MinimumPoW
+	p.PoW = DefaultMinimumPoW
 	p.Topic = TopicType{0xf2, 0x6e, 0x77, 0x79}
 	p.WorkTime = 2
 
@@ -427,7 +427,7 @@ func TestIntegrationSym(t *testing.T) {
 	p.From = f.From
 	p.Padding = []byte("test string")
 	p.Payload = []byte("extended test string")
-	p.PoW = MinimumPoW
+	p.PoW = DefaultMinimumPoW
 	p.Topic = TopicType{0xf2, 0x6e, 0x77, 0x79}
 	p.WorkTime = 2
 
@@ -517,7 +517,7 @@ func TestIntegrationSymWithFilter(t *testing.T) {
 	p.From = sig
 	p.Padding = []byte("test string")
 	p.Payload = []byte("extended test string")
-	p.PoW = MinimumPoW
+	p.PoW = DefaultMinimumPoW
 	p.Topic = TopicType{0xf2, 0x6e, 0x77, 0x79}
 	p.WorkTime = 2
 

whisper/whisperv5/doc.go

@@ -55,8 +55,8 @@ const (
 	saltLength        = 12
 	AESNonceMaxLength = 12
 
-	MaxMessageLength = 1024 * 1024
+	DefaultMaxMessageLength = 1024 * 1024
-	MinimumPoW       = 10.0     // todo: review after testing.
+	DefaultMinimumPoW       = 10.0 // todo: review after testing.
 
 	padSizeLimitLower = 128 // it can not be less - we don't want to reveal the absence of signature
 	padSizeLimitUpper = 256 // just an arbitrary number, could be changed without losing compatibility

whisper/whisperv5/message.go

@@ -215,17 +215,6 @@ func (msg *SentMessage) encryptSymmetric(key []byte) (salt []byte, nonce []byte,
 }
 
 // Wrap bundles the message into an Envelope to transmit over the network.
-//
-// pow (Proof Of Work) controls how much time to spend on hashing the message,
-// inherently controlling its priority through the network (smaller hash, bigger
-// priority).
-//
-// The user can control the amount of identity, privacy and encryption through
-// the options parameter as follows:
-//   - options.From == nil && options.To == nil: anonymous broadcast
-//   - options.From != nil && options.To == nil: signed broadcast (known sender)
-//   - options.From == nil && options.To != nil: encrypted anonymous message
-//   - options.From != nil && options.To != nil: encrypted signed message
 func (msg *SentMessage) Wrap(options *MessageParams) (envelope *Envelope, err error) {
 	if options.TTL == 0 {
 		options.TTL = DefaultTTL
@@ -236,10 +225,6 @@ func (msg *SentMessage) Wrap(options *MessageParams) (envelope *Envelope, err er
 			return nil, err
 		}
 	}
-	if len(msg.Raw) > MaxMessageLength {
-		log.Error(fmt.Sprintf("Message size must not exceed %d bytes", MaxMessageLength))
-		return nil, errors.New("Oversized message")
-	}
 	var salt, nonce []byte
 	if options.Dst != nil {
 		err = msg.encryptAsymmetric(options.Dst)
@@ -258,11 +243,6 @@ func (msg *SentMessage) Wrap(options *MessageParams) (envelope *Envelope, err er
 	if err != nil {
 		return nil, err
 	}
-	if envelope.size() > MaxMessageLength {
-		log.Error(fmt.Sprintf("Envelope size must not exceed %d bytes", MaxMessageLength))
-		return nil, errors.New("Oversized message")
-	}
-
 	return envelope, nil
 }
 

whisper/whisperv5/peer_test.go

@@ -114,7 +114,7 @@ func initialize(t *testing.T) {
 	for i := 0; i < NumNodes; i++ {
 		var node TestNode
 		node.shh = New()
-		node.shh.test = true
+		node.shh.SetMinimumPoW(0.00000001)
 		node.shh.Start(nil)
 		topics := make([]TopicType, 0)
 		topics = append(topics, sharedTopic)

whisper/whisperv5/whisper.go

@@ -66,8 +66,9 @@ type Whisper struct {
 
 	stats Statistics
 
+	minPoW       float64
+	maxMsgLength int
 	overflow     bool
-	test     bool
 }
 
 // New creates a Whisper client ready to communicate through the Ethereum P2P network.
@@ -82,6 +83,8 @@ func New() *Whisper {
 		messageQueue: make(chan *Envelope, messageQueueLimit),
 		p2pMsgQueue:  make(chan *Envelope, messageQueueLimit),
 		quit:         make(chan struct{}),
+		minPoW:       DefaultMinimumPoW,
+		maxMsgLength: DefaultMaxMessageLength,
 	}
 	whisper.filters = NewFilters(whisper)
 
@@ -122,6 +125,22 @@ func (w *Whisper) Version() uint {
 	return w.protocol.Version
 }
 
+func (w *Whisper) SetMaxMessageLength(val int) error {
+	if val <= 0 {
+		return fmt.Errorf("Invalid message length: %d", val)
+	}
+	w.maxMsgLength = val
+	return nil
+}
+
+func (w *Whisper) SetMinimumPoW(val float64) error {
+	if val <= 0.0 {
+		return fmt.Errorf("Invalid PoW: %f", val)
+	}
+	w.minPoW = val
+	return nil
+}
+
 func (w *Whisper) getPeer(peerID []byte) (*Peer, error) {
 	w.peerMu.Lock()
 	defer w.peerMu.Unlock()
@@ -358,7 +377,7 @@ func (wh *Whisper) runMessageLoop(p *Peer, rw p2p.MsgReadWriter) error {
 		if err != nil {
 			return err
 		}
-		if packet.Size > MaxMessageLength {
+		if packet.Size > uint32(wh.maxMsgLength) {
 			return fmt.Errorf("oversized message received")
 		}
 
@@ -441,7 +460,7 @@ func (wh *Whisper) add(envelope *Envelope) (bool, error) {
 		}
 	}
 
-	if envelope.size() > MaxMessageLength {
+	if envelope.size() > wh.maxMsgLength {
 		return false, fmt.Errorf("huge messages are not allowed [%x]", envelope.Hash())
 	}
 
@@ -459,7 +478,7 @@ func (wh *Whisper) add(envelope *Envelope) (bool, error) {
 		return false, fmt.Errorf("oversized salt [%x]", envelope.Hash())
 	}
 
-	if envelope.PoW() < MinimumPoW && !wh.test {
+	if envelope.PoW() < wh.minPoW {
 		log.Debug(fmt.Sprintf("envelope with low PoW dropped: %f [%x]", envelope.PoW(), envelope.Hash()))
 		return false, nil // drop envelope without error
 	}
@@ -519,6 +538,7 @@ func (w *Whisper) checkOverflow() {
 	} else if queueSize <= messageQueueLimit/2 {
 		if w.overflow {
 			w.overflow = false
+			log.Warn(fmt.Sprint("message queue overflow fixed (back to normal)"))
 		}
 	}
 }

whisper/whisperv5/whisper_test.go

@@ -305,7 +305,8 @@ func TestExpiry(t *testing.T) {
 	InitSingleTest()
 
 	w := New()
-	w.test = true
+	w.SetMinimumPoW(0.0000001)
+	defer w.SetMinimumPoW(DefaultMinimumPoW)
 	w.Start(nil)
 	defer w.Stop()