1 files changed, 85 insertions, 5 deletions

diff --git a/wireguard-go-bridge/src/api-ios.go b/wireguard-go-bridge/src/api-ios.go
index 67ce785..0fdb3be 100644
--- a/wireguard-go-bridge/src/api-ios.go
+++ b/wireguard-go-bridge/src/api-ios.go
@@ -25,6 +25,8 @@ import (
 	"os/signal"
 	"runtime"
 	"strings"
+	"syscall"
+	"time"
 	"unsafe"
 )
 
@@ -46,12 +48,54 @@ func (l *CLogger) Write(p []byte) (int, error) {
 	return len(p), nil
 }
 
-var tunnelHandles map[int32]*Device
+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)
+					}
+				})
+			}
+		}
+	}
+}
 
 func init() {
 	versionString = C.CString(WireGuardGoVersion)
 	roamingDisabled = true
-	tunnelHandles = make(map[int32]*Device)
+	tunnelHandles = make(map[int32]*DeviceState)
 	signals := make(chan os.Signal)
 	signal.Notify(signals, unix.SIGUSR2)
 	go func() {
@@ -67,6 +111,7 @@ func init() {
 			}
 		}
 	}()
+	go listenForRouteChanges()
 }
 
 //export wgSetLogger
@@ -74,6 +119,32 @@ 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))
@@ -113,18 +184,27 @@ func wgTurnOn(ifnameRef string, settings string, tunFd int32) int32 {
 	if i == math.MaxInt32 {
 		return -1
 	}
-	tunnelHandles[i] = device
+	tunnelHandles[i] = &DeviceState{
+		device:            device,
+		logger:            logger,
+		endpointsSettings: extractEndpointFromSettings(settings),
+	}
 	return i
 }
 
 //export wgTurnOff
 func wgTurnOff(tunnelHandle int32) {
-	device, ok := tunnelHandles[tunnelHandle]
+	deviceState, ok := tunnelHandles[tunnelHandle]
 	if !ok {
 		return
 	}
 	delete(tunnelHandles, tunnelHandle)
-	device.Close()
+	t := deviceState.endpointsTimer
+	if t != nil {
+		deviceState.endpointsTimer = nil
+		t.Stop()
+	}
+	deviceState.device.Close()
 }
 
 //export wgVersion