manager: pipeline UAPI requests

This avoids the somewhat expensive pipe setup.

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

7 files changed, 117 insertions, 41 deletions

diff --git a/conf/parser.go b/conf/parser.go
index d26bdea4..dd0ee317 100644
--- a/conf/parser.go
+++ b/conf/parser.go
@@ -6,8 +6,10 @@
 package conf
 
 import (
+	"bufio"
 	"encoding/base64"
 	"encoding/hex"
+	"io"
 	"net"
 	"strconv"
 	"strings"
@@ -367,8 +369,7 @@ func FromWgQuickWithUnknownEncoding(s string, name string) (*Config, error) {
 	return nil, firstErr
 }
 
-func FromUAPI(s string, existingConfig *Config) (*Config, error) {
-	lines := strings.Split(s, "\n")
+func FromUAPI(reader io.Reader, existingConfig *Config) (*Config, error) {
 	parserState := inInterfaceSection
 	conf := Config{
 		Name: existingConfig.Name,
@@ -380,9 +381,15 @@ func FromUAPI(s string, existingConfig *Config) (*Config, error) {
 		},
 	}
 	var peer *Peer
-	for _, line := range lines {
+	lineReader := bufio.NewReader(reader)
+	for {
+		line, err := lineReader.ReadString('\n')
+		if err != nil {
+			return nil, err
+		}
+		line = line[:len(line)-1]
 		if len(line) == 0 {
-			continue
+			break
 		}
 		equals := strings.IndexByte(line, '=')
 		if equals < 0 {
diff --git a/embeddable-dll-service/csharp/DemoUI/MainWindow.cs b/embeddable-dll-service/csharp/DemoUI/MainWindow.cs
index 13499fcb..50a42c42 100644
--- a/embeddable-dll-service/csharp/DemoUI/MainWindow.cs
+++ b/embeddable-dll-service/csharp/DemoUI/MainWindow.cs
@@ -58,24 +58,25 @@ namespace DemoUI
 
         private void tailTransfer()
         {
+            StreamReader reader = null;
             NamedPipeClientStream stream = null;
+            while (threadsRunning)
+            {
+                try
+                {
+                    stream = Tunnel.Service.GetPipe(configFile);
+                    stream.Connect();
+                    reader = new StreamReader(stream);
+                    break;
+                }
+                catch { }
+                Thread.Sleep(1000);
+            }
+
             try
             {
                 while (threadsRunning)
                 {
-                    while (threadsRunning)
-                    {
-                        try
-                        {
-                            stream = Tunnel.Service.GetPipe(configFile);
-                            stream.Connect();
-                            break;
-                        }
-                        catch { }
-                        Thread.Sleep(1000);
-                    }
-
-                    var reader = new StreamReader(stream);
                     stream.Write(Encoding.UTF8.GetBytes("get=1\n\n"));
                     ulong rx = 0, tx = 0;
                     while (threadsRunning)
@@ -92,14 +93,13 @@ namespace DemoUI
                             tx += ulong.Parse(line.Substring(9));
                     }
                     Invoke(new Action<ulong, ulong>(updateTransferTitle), new object[] { rx, tx });
-                    stream.Close();
                     Thread.Sleep(1000);
                 }
             }
             catch { }
             finally
             {
-                if (stream != null && stream.IsConnected)
+                if (stream.IsConnected)
                     stream.Close();
             }
         }
diff --git a/go.mod b/go.mod
index 92373c4d..20b2d06c 100644
--- a/go.mod
+++ b/go.mod
@@ -9,7 +9,7 @@ require (
 	golang.org/x/net v0.0.0-20210119194325-5f4716e94777
 	golang.org/x/sys v0.0.0-20210124154548-22da62e12c0c
 	golang.org/x/text v0.3.5
-	golang.zx2c4.com/wireguard v0.0.20201119-0.20210120232502-fcc8ad05df75
+	golang.zx2c4.com/wireguard v0.0.20201119-0.20210125194828-18e47795e598
 )
 
 replace (
diff --git a/go.sum b/go.sum
index 6ec53d78..b3f0f5b8 100644
--- a/go.sum
+++ b/go.sum
@@ -19,8 +19,8 @@ golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.5 h1:i6eZZ+zk0SOf0xgBpEpPD18qWcJda6q1sxt3S0kzyUQ=
 golang.org/x/text v0.3.5/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
-golang.zx2c4.com/wireguard v0.0.20201119-0.20210120232502-fcc8ad05df75 h1:Q8bLImgHajG+re7SSJQstC0ySZtGYx2KH6wVg8BG5YU=
-golang.zx2c4.com/wireguard v0.0.20201119-0.20210120232502-fcc8ad05df75/go.mod h1:r0ExowOoGFfDoLDxx+M9SYbNVsoZ0xviLL+K4f2mt+A=
+golang.zx2c4.com/wireguard v0.0.20201119-0.20210125194828-18e47795e598 h1:adinkobWM0mDfoPbr3b13Lwy0+G6pr4dlXmYaY5lbm8=
+golang.zx2c4.com/wireguard v0.0.20201119-0.20210125194828-18e47795e598/go.mod h1:r0ExowOoGFfDoLDxx+M9SYbNVsoZ0xviLL+K4f2mt+A=
 golang.zx2c4.com/wireguard/windows v0.0.0-20201107183008-659a4e955570 h1:sbXpfRwl+7YQY72KBuzyacG7ucr6w4OueJiEb7+pvSk=
 golang.zx2c4.com/wireguard/windows v0.0.0-20201107183008-659a4e955570/go.mod h1:KxxjdtRkfNoYDCUP5ryK7XJJNTnpC8atvtmTheChOtk=
 golang.zx2c4.com/wireguard/windows v0.0.0-20210121140954-e7fc19d483bd h1:kAUzMAITME2MCtrXBaUa9P4tndiXGWO674k9gn6ZR28=
diff --git a/manager/ipc_server.go b/manager/ipc_server.go
index 19298016..ccdfe85e 100644
--- a/manager/ipc_server.go
+++ b/manager/ipc_server.go
@@ -10,7 +10,6 @@ import (
 	"encoding/gob"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
 	"os"
 	"sync"
@@ -20,8 +19,6 @@ import (
 	"golang.org/x/sys/windows"
 	"golang.org/x/sys/windows/svc"
 
-	"golang.zx2c4.com/wireguard/ipc/winpipe"
-
 	"golang.zx2c4.com/wireguard/windows/conf"
 	"golang.zx2c4.com/wireguard/windows/services"
 	"golang.zx2c4.com/wireguard/windows/updater"
@@ -54,30 +51,30 @@ func (s *ManagerService) RuntimeConfig(tunnelName string) (*conf.Config, error)
 	if err != nil {
 		return nil, err
 	}
-	pipePath, err := services.PipePathOfTunnel(storedConfig.Name)
-	if err != nil {
-		return nil, err
-	}
-	localSystem, err := windows.CreateWellKnownSid(windows.WinLocalSystemSid)
+	pipe, err := connectTunnelServicePipe(tunnelName)
 	if err != nil {
 		return nil, err
 	}
-	pipe, err := winpipe.DialPipe(pipePath, nil, localSystem)
-	if err != nil {
-		return nil, err
-	}
-	defer pipe.Close()
-	pipe.SetWriteDeadline(time.Now().Add(time.Second * 2))
+	pipe.SetDeadline(time.Now().Add(time.Second * 2))
 	_, err = pipe.Write([]byte("get=1\n\n"))
-	if err != nil {
-		return nil, err
+	if err == windows.ERROR_NO_DATA {
+		log.Println("IPC pipe closed unexpectedly, so reopening")
+		pipe.Unlock()
+		disconnectTunnelServicePipe(tunnelName)
+		pipe, err = connectTunnelServicePipe(tunnelName)
+		if err != nil {
+			return nil, err
+		}
+		pipe.SetDeadline(time.Now().Add(time.Second * 2))
+		_, err = pipe.Write([]byte("get=1\n\n"))
 	}
-	pipe.SetReadDeadline(time.Now().Add(time.Second * 2))
-	resp, err := ioutil.ReadAll(pipe)
 	if err != nil {
+		pipe.Unlock()
+		disconnectTunnelServicePipe(tunnelName)
 		return nil, err
 	}
-	conf, err := conf.FromUAPI(string(resp), storedConfig)
+	conf, err := conf.FromUAPI(pipe, storedConfig)
+	pipe.Unlock()
 	if err != nil {
 		return nil, err
 	}
diff --git a/manager/ipc_uapi.go b/manager/ipc_uapi.go
new file mode 100644
index 00000000..b339e3ac
--- /dev/null
+++ b/manager/ipc_uapi.go
@@ -0,0 +1,71 @@
+/* SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2019-2021 WireGuard LLC. All Rights Reserved.
+ */
+
+package manager
+
+import (
+	"net"
+	"sync"
+
+	"golang.org/x/sys/windows"
+	"golang.zx2c4.com/wireguard/ipc/winpipe"
+
+	"golang.zx2c4.com/wireguard/windows/services"
+)
+
+type connectedTunnel struct {
+	net.Conn
+	sync.Mutex
+}
+
+var connectedTunnelServicePipes = make(map[string]*connectedTunnel)
+var connectedTunnelServicePipesLock sync.RWMutex
+
+func connectTunnelServicePipe(tunnelName string) (*connectedTunnel, error) {
+	connectedTunnelServicePipesLock.RLock()
+	pipe, ok := connectedTunnelServicePipes[tunnelName]
+	if ok {
+		pipe.Lock()
+		connectedTunnelServicePipesLock.RUnlock()
+		return pipe, nil
+	}
+	connectedTunnelServicePipesLock.RUnlock()
+	connectedTunnelServicePipesLock.Lock()
+	defer connectedTunnelServicePipesLock.Unlock()
+	pipe, ok = connectedTunnelServicePipes[tunnelName]
+	if ok {
+		pipe.Lock()
+		return pipe, nil
+	}
+	pipePath, err := services.PipePathOfTunnel(tunnelName)
+	if err != nil {
+		return nil, err
+	}
+	localSystem, err := windows.CreateWellKnownSid(windows.WinLocalSystemSid)
+	if err != nil {
+		return nil, err
+	}
+	pipe = &connectedTunnel{}
+	pipe.Conn, err = winpipe.DialPipe(pipePath, nil, localSystem)
+	if err != nil {
+		return nil, err
+	}
+	connectedTunnelServicePipes[tunnelName] = pipe
+	pipe.Lock()
+	return pipe, nil
+}
+
+func disconnectTunnelServicePipe(tunnelName string) {
+	connectedTunnelServicePipesLock.Lock()
+	defer connectedTunnelServicePipesLock.Unlock()
+	pipe, ok := connectedTunnelServicePipes[tunnelName]
+	if !ok {
+		return
+	}
+	pipe.Lock()
+	pipe.Close()
+	delete(connectedTunnelServicePipes, tunnelName)
+	pipe.Unlock()
+}
diff --git a/manager/tunneltracker.go b/manager/tunneltracker.go
index cfd28693..4625a8e8 100644
--- a/manager/tunneltracker.go
+++ b/manager/tunneltracker.go
@@ -273,4 +273,5 @@ func trackTunnelService(tunnelName string, service *mgr.Service) {
 		IPCServerNotifyTunnelChange(tunnelName, TunnelStopped, fmt.Errorf("Unable to continue monitoring service, so stopping: %w", err))
 		service.Control(svc.Stop)
 	}
+	disconnectTunnelServicePipe(tunnelName)
 }