Fleshing out error cases

examples/echobot/main.go

@@ -12,7 +12,7 @@ func main() {
 	ricochet.Init("./private_key", true)
 	ricochet.Connect("kwke2hntvyfqm7dr", "127.0.0.1:55555|jlq67qzo6s4yp3sp")
 	
-	// Not needed passed the initial run
+	// Not needed past the initial run
 	// TODO need to wait for contact response before sending OpenChannel
 	// ricochet.SendContactRequest("EchoBot", "I'm an EchoBot")
 

ricochet.go

@@ -144,9 +144,8 @@ func (r *Ricochet) Connect(from string, to string) error {
 		r.logger.Fatal("Cannot Marshal Open Channel Message: ", err)
 	}
 
-	openChannel := r.constructProtocol(data, 0)
+	r.sendPacket(data, 0)
 	r.logger.Print("Opening Channel: ", pc)
-	r.send(openChannel)
 
 	response, _ := r.getMessages()
 	openChannelResponse, _ := r.decodePacket(response[0], CONTROL)
@@ -203,10 +202,7 @@ func (r *Ricochet) Connect(from string, to string) error {
 	}
 
 	data, err = proto.Marshal(ahsPacket)
-
+	r.sendPacket(data, 1)
-	sendProof := r.constructProtocol(data, 1)
-	r.logger.Print("Constructed Proof: ", ahsPacket)
-	r.send(sendProof)
 	
 	response, _ = r.getMessages()
 	resultResponse, _ := r.decodePacket(response[0], AUTH)
@@ -230,9 +226,7 @@ func (r *Ricochet) OpenChannel(channelType string, id int) error {
 	}
 
 	data, _ := proto.Marshal(pc)
-	openChannel := r.constructProtocol(data, 0)
+	r.sendPacket(data, 0)
-	r.logger.Print("Opening Channel: ", pc)
-	r.send(openChannel)
 	return nil
 }
 
@@ -261,9 +255,8 @@ func (r *Ricochet) SendContactRequest(nick string, message string) {
 		r.logger.Fatal("Cannot Marshal Open Channel Message: ", err)
 	}
 
-	openChannel := r.constructProtocol(data, 0)
+	r.sendPacket(data, 0)
-	r.logger.Print("Opening Channel: ", pc)
+
-	r.send(openChannel)
 }
 
 // SendMessage sends a Chat Message (message) to a give Channel (channel).
@@ -280,9 +273,8 @@ func (r *Ricochet) SendMessage(message string, channel int) {
 	}
 
 	data, _ := proto.Marshal(chatPacket)
-	chatMessageBytes := r.constructProtocol(data, channel)
+	r.sendPacket(data, channel)
-	r.logger.Print("Sending Message: ", chatPacket)
+
-	r.send(chatMessageBytes)
 }
 
 // negotiateVersion Perform version negotiation with the connected host.
@@ -292,7 +284,7 @@ func (r *Ricochet) negotiateVersion() {
 	version[1] = 0x4D
 	version[2] = 0x01
 	version[3] = 0x01
-	r.send(version)
+	fmt.Fprintf(r.conn, "%s", version)
 	r.logger.Print("Negotiating Version ", version)
 	res, err := r.recv()
 
@@ -307,9 +299,9 @@ func (r *Ricochet) negotiateVersion() {
 	r.logger.Print("Successfully Negotiated Version ", res[0])
 }
 
-// constructProtocol places the data into a structure needed for the client to
+// sendPacket places the data into a structure needed for the client to
-// decode the packet.
+// decode the packet and writes the packet to the network.
-func (r *Ricochet) constructProtocol(data []byte, channel int) []byte {
+func (r *Ricochet) sendPacket(data []byte, channel int) {
 	header := make([]byte, 4+len(data))
 	r.logger.Print("Wrting Packet of Size: ", len(header))
 	header[0] = byte(len(header) >> 8)
@@ -317,13 +309,9 @@ func (r *Ricochet) constructProtocol(data []byte, channel int) []byte {
 	header[2] = 0x00
 	header[3] = byte(channel)
 	copy(header[4:], data[:])
-	return header
+	fmt.Fprintf(r.conn, "%s", header)
 }
 
-// send is a utility funtion to send data to the connected client.
-func (r *Ricochet) send(data []byte) {
-	fmt.Fprintf(r.conn, "%s", data)
-}
 
 // Listen blocks and waits for a new message to arrive from the connected user
 // once a message has arrived, it returns the message and the channel it occured
@@ -349,9 +337,12 @@ func (r *Ricochet) Listen() (string, int, error) {
 		ChatAcknowledge: cr,
 	}
 
-	data, _ := proto.Marshal(pc)
+	data,err := proto.Marshal(pc)
-	ack := r.constructProtocol(data, message.Channel)
+	if err != nil {
-	r.send(ack)
+	    return "",0,errors.New("Failed to serialize chat message")
+	}
+
+	r.sendPacket(data, message.Channel)
 	return message.DataPacket.GetChatMessage().GetMessageText(), message.Channel, nil
 }
 
@@ -370,7 +361,12 @@ func (r *Ricochet) ListenAndWait() error {
 		for _, packet := range packets {
 			if packet.Channel == 0 {
 				// This is a Control Channel Message
-				message, _ := r.decodePacket(packet, CONTROL)
+				message,err := r.decodePacket(packet, CONTROL)
+				
+				if err != nil {
+				    r.logger.Printf("Failed to decode control packet, discarding")
+				    break;
+				}
 
 				// Automatically accept new channels
 				if message.ControlPacket.GetOpenChannel() != nil {
@@ -384,10 +380,14 @@ func (r *Ricochet) ListenAndWait() error {
 						ChannelResult: cr,
 					}
 
-					data, _ := proto.Marshal(pc)
+					data,err := proto.Marshal(pc)
-					openChannel := r.constructProtocol(data, 0)
+					
-					r.logger.Print("Opening Channel: ", pc)
+					if err != nil {
-					r.send(openChannel)
+					    r.logger.Printf("Failed to marshal control packet. Something went very wrong.")
+					    
+					}
+					
+					r.sendPacket(data, 0)
 					r.channelState[int(message.ControlPacket.GetOpenChannel().GetChannelIdentifier())] = 1
 					break
 				}
@@ -406,7 +406,13 @@ func (r *Ricochet) ListenAndWait() error {
 			} else {
 				// At this point the only other expected type of message
 				// is a Chat Message
-				message, _ := r.decodePacket(packet, DATA)
+				message,err := r.decodePacket(packet, DATA)
+				
+			    if err != nil {
+				    r.logger.Printf("Failed to decode data packet, discarding")
+				    break;
+				}
+				
 				r.logger.Print("Receieved Data Packet: ", message)
 				r.channel <- message
 			}
@@ -454,7 +460,6 @@ func (r *Ricochet) getMessages() ([]RicochetData, error) {
 	for !finished {
 		size := int(binary.BigEndian.Uint16(buf[pos+0 : pos+2]))
 		channel := int(binary.BigEndian.Uint16(buf[pos+2 : pos+4]))
-		r.logger.Println(buf[pos+2 : pos+4])
 
 		if pos+size > len(buf) {
 			return datas, errors.New("Partial data packet received")
@@ -464,7 +469,7 @@ func (r *Ricochet) getMessages() ([]RicochetData, error) {
 			Channel: int(channel),
 			Data:    buf[pos+4 : pos+size],
 		}
-		r.logger.Println("Got new Data:", data)
+
 		datas = append(datas, data)
 		pos += size
 		if pos >= len(buf) {