manager: rewrite service arguments when migrating configs

If a service is installed already, it's a good idea to migrate its conf
argument when migrating the file name, so that these don't get out of
sync. We're already doing this when migrating from the legacy config
store, so this is also an opportunity to clean up that code a bit and
quit using regexes.

Reported-by: Станислав Мацак <smatsak@mail.ru>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 44 insertions, 0 deletions

diff --git a/manager/install.go b/manager/install.go
index bd7d23c7..f74fecf0 100644
--- a/manager/install.go
+++ b/manager/install.go
@@ -7,7 +7,9 @@ package manager
 
 import (
 	"errors"
+	"log"
 	"os"
+	"strings"
 	"time"
 
 	"golang.org/x/sys/windows"
@@ -197,3 +199,45 @@ func UninstallTunnel(name string) error {
 	}
 	return err2
 }
+
+func changeTunnelServiceConfigFilePath(name, oldPath, newPath string) {
+	var err error
+	defer func() {
+		if err != nil {
+			log.Printf("Unable to change tunnel service command line argument from %#q to %#q: %v", oldPath, newPath, err)
+		}
+	}()
+	m, err := serviceManager()
+	if err != nil {
+		return
+	}
+	serviceName, err := services.ServiceNameOfTunnel(name)
+	if err != nil {
+		return
+	}
+	service, err := m.OpenService(serviceName)
+	if err == windows.ERROR_SERVICE_DOES_NOT_EXIST {
+		err = nil
+		return
+	} else if err != nil {
+		return
+	}
+	defer service.Close()
+	config, err := service.Config()
+	if err != nil {
+		return
+	}
+	exePath, err := os.Executable()
+	if err != nil {
+		return
+	}
+	args, err := windows.DecomposeCommandLine(config.BinaryPathName)
+	if err != nil || len(args) != 3 ||
+		!strings.EqualFold(args[0], exePath) || args[1] != "/tunnelservice" || !strings.EqualFold(args[2], oldPath) {
+		err = nil
+		return
+	}
+	args[2] = newPath
+	config.BinaryPathName = windows.ComposeCommandLine(args)
+	err = service.UpdateConfig(config)
+}