Public Release

udp_generic.go

@@ -0,0 +1,123 @@
+// +build !linux
+
+// udp_generic implements the nebula UDP interface in pure Go stdlib. This
+// means it can be used on platforms like Darwin and Windows.
+
+package nebula
+
+import (
+	"context"
+	"encoding/binary"
+	"fmt"
+	"net"
+	"strconv"
+	"strings"
+)
+
+type udpAddr struct {
+	net.UDPAddr
+}
+
+type udpConn struct {
+	*net.UDPConn
+}
+
+func NewUDPAddr(ip uint32, port uint16) *udpAddr {
+	return &udpAddr{
+		UDPAddr: net.UDPAddr{
+			IP:   int2ip(ip),
+			Port: int(port),
+		},
+	}
+}
+
+func NewUDPAddrFromString(s string) *udpAddr {
+	p := strings.Split(s, ":")
+	if len(p) < 2 {
+		return nil
+	}
+
+	port, _ := strconv.Atoi(p[1])
+	return &udpAddr{
+		UDPAddr: net.UDPAddr{
+			IP:   net.ParseIP(p[0]),
+			Port: port,
+		},
+	}
+}
+
+func NewListener(ip string, port int, multi bool) (*udpConn, error) {
+	lc := NewListenConfig(multi)
+	pc, err := lc.ListenPacket(context.TODO(), "udp4", fmt.Sprintf("%s:%d", ip, port))
+	if err != nil {
+		return nil, err
+	}
+	if uc, ok := pc.(*net.UDPConn); ok {
+		return &udpConn{UDPConn: uc}, nil
+	}
+	return nil, fmt.Errorf("Unexpected PacketConn: %T %#v", pc, pc)
+}
+
+func (ua *udpAddr) Equals(t *udpAddr) bool {
+	if t == nil || ua == nil {
+		return t == nil && ua == nil
+	}
+	return ua.IP.Equal(t.IP) && ua.Port == t.Port
+}
+
+func (uc *udpConn) WriteTo(b []byte, addr *udpAddr) error {
+	_, err := uc.UDPConn.WriteToUDP(b, &addr.UDPAddr)
+	return err
+}
+
+func (uc *udpConn) LocalAddr() (*udpAddr, error) {
+	a := uc.UDPConn.LocalAddr()
+
+	switch v := a.(type) {
+	case *net.UDPAddr:
+		return &udpAddr{UDPAddr: *v}, nil
+	default:
+		return nil, fmt.Errorf("LocalAddr returned: %#v", a)
+	}
+}
+
+func (u *udpConn) reloadConfig(c *Config) {
+	// TODO
+}
+
+type rawMessage struct {
+	Len uint32
+}
+
+func (u *udpConn) ListenOut(f *Interface) {
+	plaintext := make([]byte, mtu)
+	buffer := make([]byte, mtu)
+	header := &Header{}
+	fwPacket := &FirewallPacket{}
+	udpAddr := &udpAddr{}
+	nb := make([]byte, 12, 12)
+
+	for {
+		// Just read one packet at a time
+		n, rua, err := u.ReadFromUDP(buffer)
+		if err != nil {
+			l.WithError(err).Error("Failed to read packets")
+			continue
+		}
+
+		udpAddr.UDPAddr = *rua
+		f.readOutsidePackets(udpAddr, plaintext[:0], buffer[:n], header, fwPacket, nb)
+	}
+}
+
+func udp2ip(addr *udpAddr) net.IP {
+	return addr.IP
+}
+
+func udp2ipInt(addr *udpAddr) uint32 {
+	return binary.BigEndian.Uint32(addr.IP.To4())
+}
+
+func hostDidRoam(addr *udpAddr, newaddr *udpAddr) bool {
+	return !addr.Equals(newaddr)
+}