Rewrite bridge build system

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

wireguard-go-bridge/src/api-ios.go

@@ -0,0 +1,137 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * Copyright (C) 2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+package main
+
+// #include <stdlib.h>
+// #include <sys/types.h>
+// static void callLogger(void *func, int level, const char *tag, const char *msg)
+// {
+// 	((void(*)(int, const char *, const char *))func)(level, tag, msg);
+// }
+import "C"
+
+import (
+	"bufio"
+	"git.zx2c4.com/wireguard-go/tun"
+	"golang.org/x/sys/unix"
+	"io/ioutil"
+	"log"
+	"math"
+	"os"
+	"os/signal"
+	"runtime"
+	"strings"
+	"unsafe"
+	"errors"
+)
+
+var loggerFunc unsafe.Pointer
+var versionString *C.char
+
+type CLogger struct {
+	level         C.int
+	interfaceName string
+}
+
+func (l *CLogger) Write(p []byte) (int, error) {
+	if uintptr(loggerFunc) == 0 {
+		return 0, errors.New("No logger initialized")
+	}
+	tag := C.CString("WireGuard/GoBackend/"+l.interfaceName)
+	message := C.CString(string(p))
+	C.callLogger(loggerFunc, l.level, tag, message)
+	C.free(unsafe.Pointer(tag))
+	C.free(unsafe.Pointer(message))
+	return len(p), nil
+}
+
+var tunnelHandles map[int32]*Device
+
+func init() {
+	versionString = C.CString(WireGuardGoVersion)
+	roamingDisabled = true
+	tunnelHandles = make(map[int32]*Device)
+	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
+				if uintptr(loggerFunc) != 0 {
+					tag := C.CString("WireGuard/GoBackend/Stacktrace")
+					C.callLogger(loggerFunc, 0, tag, (*_Ctype_char)(unsafe.Pointer(&buf[0])))
+					C.free(unsafe.Pointer(tag))
+				}
+			}
+		}
+	}()
+}
+
+//export wgSetLogger
+func wgSetLogger(loggerFn uintptr) {
+	loggerFunc = unsafe.Pointer(loggerFn)
+}
+
+//export wgTurnOn
+func wgTurnOn(ifnameRef string, settings string, readFn uintptr, writeFn uintptr, ctx uintptr) int32 {
+	interfaceName := string([]byte(ifnameRef))
+
+	logger := &Logger{
+		Debug: log.New(&CLogger{level: 0, interfaceName: interfaceName}, "", 0),
+		Info:  log.New(&CLogger{level: 1, interfaceName: interfaceName}, "", 0),
+		Error: log.New(&CLogger{level: 2, interfaceName: interfaceName}, "", 0),
+	}
+
+	logger.Debug.Println("Debug log enabled")
+
+	tun := tun.CreateTUN(1280, unsafe.Pointer(readFn), unsafe.Pointer(writeFn), unsafe.Pointer(ctx))
+	logger.Info.Println("Attaching to interface")
+	device := NewDevice(tun, logger)
+
+	logger.Debug.Println("Interface has MTU", device.tun.mtu)
+
+	bufferedSettings := bufio.NewReadWriter(bufio.NewReader(strings.NewReader(settings)), bufio.NewWriter(ioutil.Discard))
+	setError := ipcSetOperation(device, bufferedSettings)
+	if setError != nil {
+		logger.Error.Println(setError)
+		return -1
+	}
+
+	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 {
+		return -1
+	}
+	tunnelHandles[i] = device
+	return i
+}
+
+//export wgTurnOff
+func wgTurnOff(tunnelHandle int32) {
+	device, ok := tunnelHandles[tunnelHandle]
+	if !ok {
+		return
+	}
+	delete(tunnelHandles, tunnelHandle)
+	device.Close()
+}
+
+//export wgVersion
+func wgVersion() *C.char {
+	return versionString
+}
+
+func main() {}