Revert pure-go network monitoring and add wgSetConfig

This reverts commit 99f0e457c3 and adds a
function too.

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

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

@@ -25,8 +25,6 @@ import (
 	"os/signal"
 	"runtime"
 	"strings"
-	"syscall"
-	"time"
 	"unsafe"
 )
 
@@ -48,54 +46,12 @@ func (l *CLogger) Write(p []byte) (int, error) {
 	return len(p), nil
 }
 
-type DeviceState struct {
-	device            *Device
-	logger            *Logger
-	endpointsTimer    *time.Timer
-	endpointsSettings string
-}
-
-var tunnelHandles map[int32]*DeviceState
-
-func listenForRouteChanges() {
-	//TODO: replace with NWPathMonitor
-	data := make([]byte, os.Getpagesize())
-	routeSocket, err := unix.Socket(unix.AF_ROUTE, unix.SOCK_RAW, unix.AF_UNSPEC)
-	if err != nil {
-		return
-	}
-	for {
-		n, err := unix.Read(routeSocket, data)
-		if err != nil {
-			if errno, ok := err.(syscall.Errno); ok && errno == syscall.EINTR {
-				continue
-			}
-			return
-		}
-
-		if n < 4 {
-			continue
-		}
-		for _, deviceState := range tunnelHandles {
-			if deviceState.endpointsTimer == nil {
-				deviceState.endpointsTimer = time.AfterFunc(time.Second, func() {
-					deviceState.endpointsTimer = nil
-					bufferedSettings := bufio.NewReadWriter(bufio.NewReader(strings.NewReader(deviceState.endpointsSettings)), bufio.NewWriter(ioutil.Discard))
-					deviceState.logger.Info.Println("Setting endpoints for re-resolution due to network change")
-					err := ipcSetOperation(deviceState.device, bufferedSettings)
-					if err != nil {
-						deviceState.logger.Error.Println(err)
-					}
-				})
-			}
-		}
-	}
-}
+var tunnelHandles map[int32]*Device
 
 func init() {
 	versionString = C.CString(WireGuardGoVersion)
 	roamingDisabled = true
-	tunnelHandles = make(map[int32]*DeviceState)
+	tunnelHandles = make(map[int32]*Device)
 	signals := make(chan os.Signal)
 	signal.Notify(signals, unix.SIGUSR2)
 	go func() {
@@ -111,7 +67,6 @@ func init() {
 			}
 		}
 	}()
-	go listenForRouteChanges()
 }
 
 //export wgSetLogger
@@ -119,32 +74,6 @@ func wgSetLogger(loggerFn uintptr) {
 	loggerFunc = unsafe.Pointer(loggerFn)
 }
 
-func extractEndpointFromSettings(settings string) string {
-	var b strings.Builder
-	pubkey := ""
-	endpoint := ""
-	listenPort := "listen_port=0"
-	for _, line := range strings.Split(settings, "\n") {
-		if strings.HasPrefix(line, "listen_port=") {
-			listenPort = line
-		} else if strings.HasPrefix(line, "public_key=") {
-			if pubkey != "" && endpoint != "" {
-				b.WriteString(pubkey + "\n" + endpoint + "\n")
-			}
-			pubkey = line
-		} else if strings.HasPrefix(line, "endpoint=") {
-			endpoint = line
-		} else if line == "remove=true" {
-			pubkey = ""
-			endpoint = ""
-		}
-	}
-	if pubkey != "" && endpoint != "" {
-		b.WriteString(pubkey + "\n" + endpoint + "\n")
-	}
-	return listenPort + "\n" + b.String()
-}
-
 //export wgTurnOn
 func wgTurnOn(ifnameRef string, settings string, tunFd int32) int32 {
 	interfaceName := string([]byte(ifnameRef))
@@ -184,27 +113,31 @@ func wgTurnOn(ifnameRef string, settings string, tunFd int32) int32 {
 	if i == math.MaxInt32 {
 		return -1
 	}
-	tunnelHandles[i] = &DeviceState{
-		device:            device,
-		logger:            logger,
-		endpointsSettings: extractEndpointFromSettings(settings),
-	}
+	tunnelHandles[i] = device
 	return i
 }
 
 //export wgTurnOff
 func wgTurnOff(tunnelHandle int32) {
-	deviceState, ok := tunnelHandles[tunnelHandle]
+	device, ok := tunnelHandles[tunnelHandle]
 	if !ok {
 		return
 	}
 	delete(tunnelHandles, tunnelHandle)
-	t := deviceState.endpointsTimer
-	if t != nil {
-		deviceState.endpointsTimer = nil
-		t.Stop()
+	device.Close()
+}
+
+//export wgSetConfig
+func wgSetConfig(tunnelHandle int32, settings string) {
+	device, ok := tunnelHandles[tunnelHandle]
+	if !ok {
+		return
+	}
+	bufferedSettings := bufio.NewReadWriter(bufio.NewReader(strings.NewReader(settings)), bufio.NewWriter(ioutil.Discard))
+	err := ipcSetOperation(device, bufferedSettings)
+	if err != nil {
+		device.log.Error.Println(err)
 	}
-	deviceState.device.Close()
 }
 
 //export wgVersion

wireguard-go-bridge/wireguard.h

@@ -14,6 +14,7 @@ typedef void(*logger_fn_t)(int level, const char *msg);
 extern void wgSetLogger(logger_fn_t logger_fn);
 extern int wgTurnOn(gostring_t ifname, gostring_t settings, int32_t tun_fd);
 extern void wgTurnOff(int handle);
+extern void wgSetConfig(int handle, gostring_t settings);
 extern char *wgVersion();
 
 #endif