Use larger UDP chunks for link-local IP and let the OS fragment it. Switch to UDP for link-local peers. Minor code cleanup for TCP.

src/yggdrasil/tcp.go

@@ -158,18 +158,7 @@ func (iface *tcpInterface) handler(sock *net.TCPConn) {
 	}
 	out := make(chan []byte, 32) // TODO? what size makes sense
 	defer close(out)
-	go func() {
+	send := func(msg []byte) {
-		var stack [][]byte
-		put := func(msg []byte) {
-			stack = append(stack, msg)
-			for len(stack) > 32 {
-				util_putBytes(stack[0])
-				stack = stack[1:]
-			}
-		}
-		send := func() {
-			msg := stack[len(stack)-1]
-			stack = stack[:len(stack)-1]
 		buf := net.Buffers{tcp_msg[:],
 			wire_encode_uint64(uint64(len(msg))),
 			msg}
@@ -186,6 +175,15 @@ func (iface *tcpInterface) handler(sock *net.TCPConn) {
 		}
 		util_putBytes(msg)
 	}
+	go func() {
+		var stack [][]byte
+		put := func(msg []byte) {
+			stack = append(stack, msg)
+			for len(stack) > 32 {
+				util_putBytes(stack[0])
+				stack = stack[1:]
+			}
+		}
 		for msg := range out {
 			put(msg)
 			for len(stack) > 0 {
@@ -197,7 +195,9 @@ func (iface *tcpInterface) handler(sock *net.TCPConn) {
 					}
 					put(msg)
 				default:
-					send()
+					msg := stack[len(stack)-1]
+					stack = stack[:len(stack)-1]
+					send(msg)
 				}
 			}
 		}

src/yggdrasil/udp.go

@@ -56,6 +56,7 @@ type connInfo struct {
 	out       chan []byte
 	countIn   uint8
 	countOut  uint8
+	chunkSize uint16
 }
 
 type udpKeys struct {
@@ -73,6 +74,8 @@ func (iface *udpInterface) init(core *Core, addr string) {
 	if err != nil {
 		panic(err)
 	}
+	//iface.sock.SetReadBuffer(1048576)
+	//iface.sock.SetWriteBuffer(1048576)
 	iface.conns = make(map[connAddr]*connInfo)
 	go iface.reader()
 }
@@ -168,6 +171,10 @@ func (iface *udpInterface) handleKeys(msg []byte, addr connAddr) {
 			linkIn:    make(chan []byte, 1),
 			keysIn:    make(chan *udpKeys, 1),
 			out:       make(chan []byte, 32),
+			chunkSize: 576 - 60 - 8 - 3, // max save - max ip - udp header - chunk overhead
+		}
+		if udpAddr.IP.IsLinkLocalUnicast() {
+			conn.chunkSize = 65535 - 8 - 3
 		}
 		/*
 		   conn.in = func (msg []byte) { conn.peer.handlePacket(msg, conn.linkIn) }
@@ -236,8 +243,8 @@ func (iface *udpInterface) handleKeys(msg []byte, addr connAddr) {
 			for msg := range conn.out {
 				chunks = chunks[:0]
 				bs := msg
-				for len(bs) > udp_chunkSize {
+				for len(bs) > int(conn.chunkSize) {
-					chunks, bs = append(chunks, bs[:udp_chunkSize]), bs[udp_chunkSize:]
+					chunks, bs = append(chunks, bs[:conn.chunkSize]), bs[conn.chunkSize:]
 				}
 				chunks = append(chunks, bs)
 				//iface.core.log.Println("DEBUG: out chunks:", len(chunks), len(msg))
@@ -284,7 +291,7 @@ func (iface *udpInterface) handlePacket(msg []byte, addr connAddr) {
 }
 
 func (iface *udpInterface) reader() {
-	bs := make([]byte, 2048) // This needs to be large enough for everything...
+	bs := make([]byte, 65536) // This needs to be large enough for everything...
 	for {
 		//iface.core.log.Println("Starting read")
 		n, udpAddr, err := iface.sock.ReadFromUDP(bs)
@@ -293,9 +300,7 @@ func (iface *udpInterface) reader() {
 			panic(err)
 			break
 		}
-		if n > 1500 {
+		//iface.core.log.Println("DEBUG: recv len:", n)
-			panic(n)
-		}
 		//msg := append(util_getBytes(), bs[:n]...)
 		msg := bs[:n]
 		var addr connAddr
@@ -319,7 +324,8 @@ func (iface *udpInterface) reader() {
 
 ////////////////////////////////////////////////////////////////////////////////
 
-const udp_chunkSize = 508 // Apparently the maximum guaranteed safe IPv4 size
+//const udp_chunkSize = 508 // Apparently the maximum guaranteed safe IPv4 size
+//const udp_chunkSize = 65535 - 3 - 8
 
 func udp_decode(bs []byte) (chunks, chunk, count uint8, payload []byte) {
 	if len(bs) >= 3 {

src/yggdrasil/wire.go

@@ -21,7 +21,7 @@ const (
 	wire_DHTLookupResponse          // inside protocol traffic header
 	wire_SearchRequest              // inside protocol traffic header
 	wire_SearchResponse             // inside protocol traffic header
-	//wire_Keys                 // udp key packet (boxPub, sigPub)
+	wire_Keys                       // udp key packet (boxPub, sigPub)
 )
 
 // Encode uint64 using a variable length scheme

yggdrasil.go

@@ -177,7 +177,7 @@ func (n *node) listen() {
 		saddr := addr.String()
 		//if _, isIn := n.peers[saddr]; isIn { continue }
 		//n.peers[saddr] = struct{}{}
-		n.core.DEBUG_addTCPConn(saddr) // FIXME? can result in 2 connections per peer
+		n.core.DEBUG_maybeSendUDPKeys(saddr) // FIXME? can result in 2 connections per peer
 		//fmt.Println("DEBUG:", "added multicast peer:", saddr)
 	}
 }
@@ -188,8 +188,8 @@ func (n *node) announce() {
 		panic(err)
 	}
 	var anAddr net.TCPAddr
-	tcpAddr := n.core.DEBUG_getGlobalTCPAddr()
+	myAddr := n.core.DEBUG_getGlobalUDPAddr()
-	anAddr.Port = tcpAddr.Port
+	anAddr.Port = myAddr.Port
 	destAddr, err := net.ResolveUDPAddr("udp6", multicastAddr)
 	if err != nil {
 		panic(err)