device: return generic error from Ipc{Get,Set}Operation.

device/boundif_windows.go → conn/boundif_windows.go

@@ -3,11 +3,10 @@
  * Copyright (C) 2017-2019 WireGuard LLC. All Rights Reserved.
  */
 
-package device
+package conn
 
 import (
 	"encoding/binary"
-	"errors"
 	"unsafe"
 
 	"golang.org/x/sys/windows"
@@ -18,17 +17,13 @@ const (
 	sockoptIPV6_UNICAST_IF = 31
 )
 
-func (device *Device) BindSocketToInterface4(interfaceIndex uint32, blackhole bool) error {
+func (bind *nativeBind) BindSocketToInterface4(interfaceIndex uint32, blackhole bool) error {
 	/* MSDN says for IPv4 this needs to be in net byte order, so that it's like an IP address with leading zeros. */
 	bytes := make([]byte, 4)
 	binary.BigEndian.PutUint32(bytes, interfaceIndex)
 	interfaceIndex = *(*uint32)(unsafe.Pointer(&bytes[0]))
 
-	if device.net.bind == nil {
-		return errors.New("Bind is not yet initialized")
-	}
-
-	sysconn, err := device.net.bind.(*nativeBind).ipv4.SyscallConn()
+	sysconn, err := bind.ipv4.SyscallConn()
 	if err != nil {
 		return err
 	}
@@ -41,12 +36,12 @@ func (device *Device) BindSocketToInterface4(interfaceIndex uint32, blackhole bo
 	if err != nil {
 		return err
 	}
-	device.net.bind.(*nativeBind).blackhole4 = blackhole
+	bind.blackhole4 = blackhole
 	return nil
 }
 
-func (device *Device) BindSocketToInterface6(interfaceIndex uint32, blackhole bool) error {
-	sysconn, err := device.net.bind.(*nativeBind).ipv6.SyscallConn()
+func (bind *nativeBind) BindSocketToInterface6(interfaceIndex uint32, blackhole bool) error {
+	sysconn, err := bind.ipv6.SyscallConn()
 	if err != nil {
 		return err
 	}
@@ -59,6 +54,6 @@ func (device *Device) BindSocketToInterface6(interfaceIndex uint32, blackhole bo
 	if err != nil {
 		return err
 	}
-	device.net.bind.(*nativeBind).blackhole6 = blackhole
+	bind.blackhole6 = blackhole
 	return nil
 }

conn/conn.go

@@ -0,0 +1,101 @@
+/* SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2017-2019 WireGuard LLC. All Rights Reserved.
+ */
+
+// Package conn implements WireGuard's network connections.
+package conn
+
+import (
+	"errors"
+	"net"
+	"strings"
+)
+
+// A Bind listens on a port for both IPv6 and IPv4 UDP traffic.
+type Bind interface {
+	// LastMark reports the last mark set for this Bind.
+	LastMark() uint32
+
+	// SetMark sets the mark for each packet sent through this Bind.
+	// This mark is passed to the kernel as the socket option SO_MARK.
+	SetMark(mark uint32) error
+
+	// ReceiveIPv6 reads an IPv6 UDP packet into b.
+	//
+	// It reports the number of bytes read, n,
+	// the packet source address ep,
+	// and any error.
+	ReceiveIPv6(buff []byte) (n int, ep Endpoint, err error)
+
+	// ReceiveIPv4 reads an IPv4 UDP packet into b.
+	//
+	// It reports the number of bytes read, n,
+	// the packet source address ep,
+	// and any error.
+	ReceiveIPv4(b []byte) (n int, ep Endpoint, err error)
+
+	// Send writes a packet b to address ep.
+	Send(b []byte, ep Endpoint) error
+
+	// Close closes the Bind connection.
+	Close() error
+}
+
+// CreateBind creates a Bind bound to a port.
+//
+// The value actualPort reports the actual port number the Bind
+// object gets bound to.
+func CreateBind(port uint16) (b Bind, actualPort uint16, err error) {
+	return createBind(port)
+}
+
+// BindToInterface is implemented by Bind objects that support being
+// tied to a single network interface.
+type BindToInterface interface {
+	BindToInterface4(interfaceIndex uint32, blackhole bool) error
+	BindToInterface6(interfaceIndex uint32, blackhole bool) error
+}
+
+// An Endpoint maintains the source/destination caching for a peer.
+//
+//	dst : the remote address of a peer ("endpoint" in uapi terminology)
+//	src : the local address from which datagrams originate going to the peer
+type Endpoint interface {
+	ClearSrc()           // clears the source address
+	SrcToString() string // returns the local source address (ip:port)
+	DstToString() string // returns the destination address (ip:port)
+	DstToBytes() []byte  // used for mac2 cookie calculations
+	DstIP() net.IP
+	SrcIP() net.IP
+}
+
+func parseEndpoint(s string) (*net.UDPAddr, error) {
+	// ensure that the host is an IP address
+
+	host, _, err := net.SplitHostPort(s)
+	if err != nil {
+		return nil, err
+	}
+	if i := strings.LastIndexByte(host, '%'); i > 0 && strings.IndexByte(host, ':') >= 0 {
+		// Remove the scope, if any. ResolveUDPAddr below will use it, but here we're just
+		// trying to make sure with a small sanity test that this is a real IP address and
+		// not something that's likely to incur DNS lookups.
+		host = host[:i]
+	}
+	if ip := net.ParseIP(host); ip == nil {
+		return nil, errors.New("Failed to parse IP address: " + host)
+	}
+
+	// parse address and port
+
+	addr, err := net.ResolveUDPAddr("udp", s)
+	if err != nil {
+		return nil, err
+	}
+	ip4 := addr.IP.To4()
+	if ip4 != nil {
+		addr.IP = ip4
+	}
+	return addr, err
+}

device/conn_default.go → conn/conn_default.go

@@ -5,7 +5,7 @@
  * Copyright (C) 2017-2019 WireGuard LLC. All Rights Reserved.
  */
 
-package device
+package conn
 
 import (
 	"net"
@@ -67,16 +67,13 @@ func (e *NativeEndpoint) SrcToString() string {
 }
 
 func listenNet(network string, port int) (*net.UDPConn, int, error) {
-
-	// listen
-
 	conn, err := net.ListenUDP(network, &net.UDPAddr{Port: port})
 	if err != nil {
 		return nil, 0, err
 	}
 
-	// retrieve port
-
+	// Retrieve port.
+	// TODO(crawshaw): under what circumstances is this necessary?
 	laddr := conn.LocalAddr()
 	uaddr, err := net.ResolveUDPAddr(
 		laddr.Network(),
@@ -100,7 +97,7 @@ func extractErrno(err error) error {
 	return syscallErr.Err
 }
 
-func CreateBind(uport uint16, device *Device) (Bind, uint16, error) {
+func createBind(uport uint16) (Bind, uint16, error) {
 	var err error
 	var bind nativeBind
 
@@ -135,6 +132,8 @@ func (bind *nativeBind) Close() error {
 	return err2
 }
 
+func (bind *nativeBind) LastMark() uint32 { return 0 }
+
 func (bind *nativeBind) ReceiveIPv4(buff []byte) (int, Endpoint, error) {
 	if bind.ipv4 == nil {
 		return 0, nil, syscall.EAFNOSUPPORT