1 files changed, 193 insertions, 0 deletions
diff --git a/tunnel/tools/libwg-go/api-android.go b/tunnel/tools/libwg-go/api-android.go
new file mode 100644
index 00000000..7a393cae
--- /dev/null
+++ b/tunnel/tools/libwg-go/api-android.go
@@ -0,0 +1,193 @@
+/* SPDX-License-Identifier: Apache-2.0
+ *
+ * Copyright (C) 2017-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+package main
+
+// #cgo LDFLAGS: -llog
+// #include <android/log.h>
+import "C"
+
+import (
+	"bufio"
+	"golang.org/x/sys/unix"
+	"golang.zx2c4.com/wireguard/device"
+	"golang.zx2c4.com/wireguard/ipc"
+	"golang.zx2c4.com/wireguard/tun"
+	"bytes"
+	"log"
+	"math"
+	"net"
+	"os"
+	"os/signal"
+	"runtime"
+	"strings"
+	"unsafe"
+)
+
+type AndroidLogger struct {
+	level         C.int
+	interfaceName string
+}
+
+func (l AndroidLogger) Write(p []byte) (int, error) {
+	C.__android_log_write(l.level, C.CString("WireGuard/GoBackend/"+l.interfaceName), C.CString(string(p)))
+	return len(p), nil
+}
+
+type TunnelHandle struct {
+	device *device.Device
+	uapi   net.Listener
+}
+
+var tunnelHandles map[int32]TunnelHandle
+
+func init() {
+	device.RoamingDisabled = true
+	tunnelHandles = make(map[int32]TunnelHandle)
+	signals := make(chan os.Signal)
+	signal.Notify(signals, unix.SIGUSR2)
+	go func() {
+		buf := make([]byte, os.Getpagesize())
+		for {
+			select {
+			case <-signals:
+				n := runtime.Stack(buf, true)
+				buf[n] = 0
+				C.__android_log_write(C.ANDROID_LOG_ERROR, C.CString("WireGuard/GoBackend/Stacktrace"), (*C.char)(unsafe.Pointer(&buf[0])))
+			}
+		}
+	}()
+}
+
+//export wgTurnOn
+func wgTurnOn(ifnameRef string, tunFd int32, settings string) int32 {
+	interfaceName := string([]byte(ifnameRef))
+
+	logger := &device.Logger{
+		Debug: log.New(&AndroidLogger{level: C.ANDROID_LOG_DEBUG, interfaceName: interfaceName}, "", 0),
+		Info:  log.New(&AndroidLogger{level: C.ANDROID_LOG_INFO, interfaceName: interfaceName}, "", 0),
+		Error: log.New(&AndroidLogger{level: C.ANDROID_LOG_ERROR, interfaceName: interfaceName}, "", 0),
+	}
+
+	logger.Debug.Println("Debug log enabled")
+
+	tun, name, err := tun.CreateUnmonitoredTUNFromFD(int(tunFd))
+	if err != nil {
+		unix.Close(int(tunFd))
+		logger.Error.Println(err)
+		return -1
+	}
+
+	logger.Info.Println("Attaching to interface", name)
+	device := device.NewDevice(tun, logger)
+
+	setError := device.IpcSetOperation(bufio.NewReader(strings.NewReader(settings)))
+	if setError != nil {
+		unix.Close(int(tunFd))
+		logger.Error.Println(setError)
+		return -1
+	}
+
+	var uapi net.Listener
+
+	uapiFile, err := ipc.UAPIOpen(name)
+	if err != nil {
+		logger.Error.Println(err)
+	} else {
+		uapi, err = ipc.UAPIListen(name, uapiFile)
+		if err != nil {
+			uapiFile.Close()
+			logger.Error.Println(err)
+		} else {
+			go func() {
+				for {
+					conn, err := uapi.Accept()
+					if err != nil {
+						return
+					}
+					go device.IpcHandle(conn)
+				}
+			}()
+		}
+	}
+
+	device.Up()
+	logger.Info.Println("Device started")
+
+	var i int32
+	for i = 0; i < math.MaxInt32; i++ {
+		if _, exists := tunnelHandles[i]; !exists {
+			break
+		}
+	}
+	if i == math.MaxInt32 {
+		unix.Close(int(tunFd))
+		return -1
+	}
+	tunnelHandles[i] = TunnelHandle{device: device, uapi: uapi}
+	return i
+}
+
+//export wgTurnOff
+func wgTurnOff(tunnelHandle int32) {
+	handle, ok := tunnelHandles[tunnelHandle]
+	if !ok {
+		return
+	}
+	delete(tunnelHandles, tunnelHandle)
+	if handle.uapi != nil {
+		handle.uapi.Close()
+	}
+	handle.device.Close()
+}
+
+//export wgGetSocketV4
+func wgGetSocketV4(tunnelHandle int32) int32 {
+	handle, ok := tunnelHandles[tunnelHandle]
+	if !ok {
+		return -1
+	}
+	fd, err := handle.device.PeekLookAtSocketFd4()
+	if err != nil {
+		return -1
+	}
+	return int32(fd)
+}
+
+//export wgGetSocketV6
+func wgGetSocketV6(tunnelHandle int32) int32 {
+	handle, ok := tunnelHandles[tunnelHandle]
+	if !ok {
+		return -1
+	}
+	fd, err := handle.device.PeekLookAtSocketFd6()
+	if err != nil {
+		return -1
+	}
+	return int32(fd)
+}
+
+//export wgGetConfig
+func wgGetConfig(tunnelHandle int32) *C.char {
+	handle, ok := tunnelHandles[tunnelHandle]
+	if !ok {
+		return nil
+	}
+	settings := new(bytes.Buffer)
+	writer := bufio.NewWriter(settings)
+	err := handle.device.IpcGetOperation(writer)
+	if err != nil {
+		return nil
+	}
+	writer.Flush()
+	return C.CString(settings.String())
+}
+
+//export wgVersion
+func wgVersion() *C.char {
+	return C.CString(device.WireGuardGoVersion)
+}
+
+func main() {}