1 files changed, 92 insertions, 14 deletions

diff --git a/conf/path_windows.go b/conf/path_windows.go
index a53968c5..0ff0a057 100644
--- a/conf/path_windows.go
+++ b/conf/path_windows.go
@@ -1,33 +1,36 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2019 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2019-2022 WireGuard LLC. All Rights Reserved.
  */
 
 package conf
 
 import (
+	"errors"
 	"os"
 	"path/filepath"
+	"strings"
+	"unsafe"
 
 	"golang.org/x/sys/windows"
 )
 
-var cachedConfigFileDir string
-var cachedRootDir string
-var disableAutoMigration bool
+var (
+	cachedConfigFileDir string
+	cachedRootDir       string
+)
 
 func tunnelConfigurationsDirectory() (string, error) {
 	if cachedConfigFileDir != "" {
 		return cachedConfigFileDir, nil
 	}
-	root, err := RootDirectory()
+	root, err := RootDirectory(true)
 	if err != nil {
 		return "", err
 	}
 	c := filepath.Join(root, "Configurations")
-	maybeMigrate(c)
-	err = os.MkdirAll(c, os.ModeDir|0700)
-	if err != nil {
+	err = os.Mkdir(c, os.ModeDir|0o700)
+	if err != nil && !os.IsExist(err) {
 		return "", err
 	}
 	cachedConfigFileDir = c
@@ -39,22 +42,97 @@ func tunnelConfigurationsDirectory() (string, error) {
 // consumers of our libraries who might want to do strange things.
 func PresetRootDirectory(root string) {
 	cachedRootDir = root
-	disableAutoMigration = true
 }
 
-func RootDirectory() (string, error) {
+func RootDirectory(create bool) (string, error) {
 	if cachedRootDir != "" {
 		return cachedRootDir, nil
 	}
-	root, err := windows.KnownFolderPath(windows.FOLDERID_LocalAppData, windows.KF_FLAG_CREATE)
+	root, err := windows.KnownFolderPath(windows.FOLDERID_ProgramFiles, windows.KF_FLAG_DEFAULT)
+	if err != nil {
+		return "", err
+	}
+	root = filepath.Join(root, "WireGuard")
+	if !create {
+		return filepath.Join(root, "Data"), nil
+	}
+	root16, err := windows.UTF16PtrFromString(root)
+	if err != nil {
+		return "", err
+	}
+
+	// The root directory inherits its ACL from Program Files; we don't want to mess with that
+	err = windows.CreateDirectory(root16, nil)
+	if err != nil && err != windows.ERROR_ALREADY_EXISTS {
+		return "", err
+	}
+
+	dataDirectorySd, err := windows.SecurityDescriptorFromString("O:SYG:SYD:PAI(A;OICI;FA;;;SY)(A;OICI;FA;;;BA)")
 	if err != nil {
 		return "", err
 	}
-	c := filepath.Join(root, "WireGuard")
-	err = os.MkdirAll(c, os.ModeDir|0700)
+	dataDirectorySa := &windows.SecurityAttributes{
+		Length:             uint32(unsafe.Sizeof(windows.SecurityAttributes{})),
+		SecurityDescriptor: dataDirectorySd,
+	}
+
+	data := filepath.Join(root, "Data")
+	data16, err := windows.UTF16PtrFromString(data)
 	if err != nil {
 		return "", err
 	}
-	cachedRootDir = c
+	var dataHandle windows.Handle
+	for {
+		err = windows.CreateDirectory(data16, dataDirectorySa)
+		if err != nil && err != windows.ERROR_ALREADY_EXISTS {
+			return "", err
+		}
+		dataHandle, err = windows.CreateFile(data16, windows.READ_CONTROL|windows.WRITE_OWNER|windows.WRITE_DAC, windows.FILE_SHARE_READ|windows.FILE_SHARE_WRITE|windows.FILE_SHARE_DELETE, nil, windows.OPEN_EXISTING, windows.FILE_FLAG_BACKUP_SEMANTICS|windows.FILE_FLAG_OPEN_REPARSE_POINT|windows.FILE_ATTRIBUTE_DIRECTORY, 0)
+		if err != nil && err != windows.ERROR_FILE_NOT_FOUND {
+			return "", err
+		}
+		if err == nil {
+			break
+		}
+	}
+	defer windows.CloseHandle(dataHandle)
+	var fileInfo windows.ByHandleFileInformation
+	err = windows.GetFileInformationByHandle(dataHandle, &fileInfo)
+	if err != nil {
+		return "", err
+	}
+	if fileInfo.FileAttributes&windows.FILE_ATTRIBUTE_DIRECTORY == 0 {
+		return "", errors.New("Data directory is actually a file")
+	}
+	if fileInfo.FileAttributes&windows.FILE_ATTRIBUTE_REPARSE_POINT != 0 {
+		return "", errors.New("Data directory is reparse point")
+	}
+	buf := make([]uint16, windows.MAX_PATH+4)
+	for {
+		bufLen, err := windows.GetFinalPathNameByHandle(dataHandle, &buf[0], uint32(len(buf)), 0)
+		if err != nil {
+			return "", err
+		}
+		if bufLen < uint32(len(buf)) {
+			break
+		}
+		buf = make([]uint16, bufLen)
+	}
+	if !strings.EqualFold(`\\?\`+data, windows.UTF16ToString(buf[:])) {
+		return "", errors.New("Data directory jumped to unexpected location")
+	}
+	err = windows.SetKernelObjectSecurity(dataHandle, windows.DACL_SECURITY_INFORMATION|windows.GROUP_SECURITY_INFORMATION|windows.OWNER_SECURITY_INFORMATION|windows.PROTECTED_DACL_SECURITY_INFORMATION, dataDirectorySd)
+	if err != nil {
+		return "", err
+	}
+	cachedRootDir = data
 	return cachedRootDir, nil
 }
+
+func LogFile(createRoot bool) (string, error) {
+	root, err := RootDirectory(createRoot)
+	if err != nil {
+		return "", err
+	}
+	return filepath.Join(root, "log.bin"), nil
+}