Initial commit

raknet/packets.go

@@ -0,0 +1,166 @@
+package raknet
+
+import (
+	"encoding/binary"
+	"net"
+)
+
+func BuildUnconnectedPong(timestamp int64, serverGUID int64, motd string) []byte {
+	s := NewStream()
+	s.WriteByte(0x1c)
+	s.WriteInt64BE(timestamp)
+	s.WriteInt64BE(serverGUID)
+	s.WriteMagic()
+	s.WriteString(motd)
+	return s.Bytes()
+}
+
+func BuildOpenConnectionReply1(serverGUID int64, mtu uint16) []byte {
+	s := NewStream()
+	s.WriteByte(0x06)
+	s.WriteMagic()
+	s.WriteInt64BE(serverGUID)
+	s.WriteBool(false)
+	s.WriteUint16BE(mtu)
+	return s.Bytes()
+}
+
+func BuildOpenConnectionReply2(serverGUID int64, clientAddr net.UDPAddr, mtu uint16) []byte {
+	s := NewStream()
+	s.WriteByte(0x08)
+	s.WriteMagic()
+	s.WriteInt64BE(serverGUID)
+	s.WriteAddress(clientAddr)
+	s.WriteUint16BE(mtu)
+	s.WriteBool(false)
+	return s.Bytes()
+}
+
+func BuildConnectionRequestAccepted(clientAddr net.UDPAddr, clientTimestamp int64, serverTimestamp int64) []byte {
+	s := NewStream()
+	s.WriteByte(0x10)
+	s.WriteAddress(clientAddr)
+	s.WriteUint16BE(0)
+	for i := 0; i < 10; i++ {
+		s.WriteAddress(net.UDPAddr{IP: net.ParseIP("0.0.0.0"), Port: 0})
+	}
+	s.WriteInt64BE(clientTimestamp)
+	s.WriteInt64BE(serverTimestamp)
+	return s.Bytes()
+}
+
+func BuildConnectedPong(pingTime int64, pongTime int64) []byte {
+	s := NewStream()
+	s.WriteByte(0x03)
+	s.WriteInt64BE(pingTime)
+	s.WriteInt64BE(pongTime)
+	return s.Bytes()
+}
+
+func ParseUnconnectedPing(data []byte) (timestamp int64, guid int64, ok bool) {
+	if len(data) < 1+8+16 {
+		return
+	}
+	timestamp = int64(binary.BigEndian.Uint64(data[1:9]))
+	magic := RaknetMagic()
+	for i, b := range magic {
+		if data[9+i] != b {
+			return
+		}
+	}
+	if len(data) >= 1+8+16+8 {
+		guid = int64(binary.BigEndian.Uint64(data[25:33]))
+	}
+	ok = true
+	return
+}
+
+func ParseOCR1(data []byte) (proto byte, mtu uint16, ok bool) {
+	if len(data) < 1+16+1 {
+		return
+	}
+	magic := RaknetMagic()
+	for i, b := range magic {
+		if data[1+i] != b {
+			return
+		}
+	}
+	proto = data[17]
+	mtu = uint16(len(data) + 28)
+	ok = true
+	return
+}
+
+func ParseOCR2(data []byte) (clientGUID int64, clientAddr net.UDPAddr, mtu uint16, ok bool) {
+	s := NewStreamBytes(data)
+	s.Skip(1)
+	magic := RaknetMagic()
+	mb, err := s.ReadBytes(16)
+	if err != nil {
+		return
+	}
+	for i, b := range magic {
+		if mb[i] != b {
+			return
+		}
+	}
+	addr, err := s.ReadAddress()
+	if err != nil {
+		return
+	}
+	clientAddr = addr
+	mtuV, err := s.ReadUint16BE()
+	if err != nil {
+		return
+	}
+	mtu = mtuV
+	guidV, err := s.ReadInt64BE()
+	if err != nil {
+		return
+	}
+	clientGUID = guidV
+	ok = true
+	return
+}
+
+func ParseConnectionRequest(payload []byte) (clientGUID int64, timestamp int64, ok bool) {
+	if len(payload) < 17 {
+		return
+	}
+	if payload[0] != 0x09 {
+		return
+	}
+	s := NewStreamBytes(payload[1:])
+	g, err := s.ReadInt64BE()
+	if err != nil {
+		return
+	}
+	t, err := s.ReadInt64BE()
+	if err != nil {
+		return
+	}
+	clientGUID = g
+	timestamp = t
+	ok = true
+	return
+}
+
+func IsNewIncomingConnection(payload []byte) bool {
+	return len(payload) > 0 && payload[0] == 0x13
+}
+
+func IsDisconnect(payload []byte) bool {
+	return len(payload) > 0 && payload[0] == 0x15
+}
+
+func ParseConnectedPing(payload []byte) (timestamp int64, ok bool) {
+	if len(payload) < 9 || payload[0] != 0x00 {
+		return
+	}
+	s := NewStreamBytes(payload[1:])
+	t, err := s.ReadInt64BE()
+	if err != nil {
+		return
+	}
+	return t, true
+}