macOS App Sandbox

CMakeLists.txt

@@ -237,10 +237,6 @@ if(OWNCLOUD_5XX_NO_BLACKLIST)
     add_definitions(-DOWNCLOUD_5XX_NO_BLACKLIST=1)
 endif()
 
-if(APPLE)
-  set( SOCKETAPI_TEAM_IDENTIFIER_PREFIX "" CACHE STRING "SocketApi prefix (including a following dot) that must match the codesign key's TeamIdentifier/Organizational Unit" )
-endif()
-
 if(BUILD_CLIENT)
     OPTION(GUI_TESTING "Build with gui introspection features of socket api" OFF)
 

NEXTCLOUD.cmake

@@ -31,6 +31,7 @@ set( APPLICATION_ICON_SET   "SVG" )
 set( APPLICATION_SERVER_URL "" CACHE STRING "URL for the server to use. If entered, the UI field will be pre-filled with it" )
 set( APPLICATION_SERVER_URL_ENFORCE ON ) # If set and APPLICATION_SERVER_URL is defined, the server can only connect to the pre-defined URL
 set( APPLICATION_REV_DOMAIN "com.nextcloud.desktopclient" )
+set( DEVELOPMENT_TEAM "NKUJUXUJ3B" CACHE STRING "Apple Development Team ID for code signing" )
 set( APPLICATION_VIRTUALFILE_SUFFIX "nextcloud" CACHE STRING "Virtual file suffix (not including the .)")
 set( APPLICATION_OCSP_STAPLING_ENABLED OFF )
 set( APPLICATION_FORBID_BAD_SSL OFF )

REUSE.toml

@@ -31,6 +31,7 @@ SPDX-License-Identifier = "GPL-2.0-or-later"
 
 [[annotations]]
 path = [
+    "admin/osx/container-migration.plist.cmake",
     "admin/osx/TransifexStringCatalogSanitizer/Package.swift",
     "admin/osx/TransifexStringCatalogSanitizer/Package.resolved",
     "admin/osx/TransifexStringCatalogSanitizer/README.md",

admin/osx/CMakeLists.txt

@@ -21,6 +21,11 @@ else()
     set(DEBUG_ENTITLEMENTS "")
 endif()
 
+# Sandbox migration description
+configure_file(container-migration.plist.cmake ${CMAKE_CURRENT_BINARY_DIR}/container-migration.plist @ONLY)
+install(FILES ${CMAKE_BINARY_DIR}/admin/osx/container-migration.plist
+        DESTINATION ${OWNCLOUD_OSX_BUNDLE}/Contents/Resources)
+
 configure_file(create_mac.sh.cmake ${CMAKE_CURRENT_BINARY_DIR}/create_mac.sh)
 configure_file(macosx.entitlements.cmake ${CMAKE_CURRENT_BINARY_DIR}/macosx.entitlements)
 configure_file(macosx.pkgproj.cmake ${CMAKE_CURRENT_BINARY_DIR}/macosx.pkgproj)

admin/osx/container-migration.plist.cmake

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>Move</key>
+	<array>
+		<string>${Library}/Preferences/@APPLICATION_NAME@</string>
+	</array>
+</dict>
+</plist>

admin/osx/macosx.entitlements.cmake

@@ -2,9 +2,15 @@
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
 <dict>
+	<key>com.apple.security.app-sandbox</key>
+	<true/>
+	<key>com.apple.security.network.client</key>
+	<true/>
+	<key>com.apple.security.files.user-selected.read-write</key>
+	<true/>
 	<key>com.apple.security.application-groups</key>
 	<array>
-		<string>@SOCKETAPI_TEAM_IDENTIFIER_PREFIX@@APPLICATION_REV_DOMAIN@</string>
+		<string>@DEVELOPMENT_TEAM@.@APPLICATION_REV_DOMAIN@</string>
 	</array>
 @DEBUG_ENTITLEMENTS@
 </dict>

cmake/modules/MacOSXBundleInfo.plist.in

@@ -91,6 +91,6 @@
         </dict>
     </array>
     <key>NCFPKAppGroupIdentifier</key>
-    <string>@SOCKETAPI_TEAM_IDENTIFIER_PREFIX@@APPLICATION_REV_DOMAIN@</string>
+    <string>@DEVELOPMENT_TEAM@.@APPLICATION_REV_DOMAIN@</string>
 </dict>
 </plist>

config.h.in

@@ -5,7 +5,7 @@
 #cmakedefine WITH_QTKEYCHAIN 1
 #cmakedefine BUILD_FILE_PROVIDER_MODULE "@BUILD_FILE_PROVIDER_MODULE@"
 #cmakedefine WITH_PROVIDERS "@WITH_PROVIDERS@"
-#define SOCKETAPI_TEAM_IDENTIFIER_PREFIX "@SOCKETAPI_TEAM_IDENTIFIER_PREFIX@"
+#cmakedefine DEVELOPMENT_TEAM "@DEVELOPMENT_TEAM@"
 
 #cmakedefine THEME_CLASS @THEME_CLASS@
 #cmakedefine THEME_INCLUDE @THEME_INCLUDE@

doc/macOS-Sandbox-Qt.md

@@ -0,0 +1,231 @@
+<!--
+  - SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
+  - SPDX-License-Identifier: GPL-2.0-or-later
+-->
+
+# macOS App Sandbox Support for Qt Applications
+
+## Overview
+
+This document explains how to make the Nextcloud Desktop Client work properly with macOS App Sandbox when using Qt. The key issue is that Qt's `QFileDialog` returns security-scoped URLs that require explicit access management in sandboxed applications.
+
+## The Problem
+
+When running a sandboxed macOS application with the `com.apple.security.files.user-selected.read-write` entitlement, file operations on user-selected files (via `QFileDialog`) will fail unless you explicitly:
+
+1. Call `startAccessingSecurityScopedResource()` on the URL before accessing the file
+2. Call `stopAccessingSecurityScopedResource()` when done
+
+This is **required by macOS sandbox security**, but Qt does not handle this automatically. The underlying issue is that:
+
+- `QFileDialog::getSaveFileUrl()` returns a `QUrl` that represents a security-scoped bookmark
+- Without calling `startAccessingSecurityScopedResource()`, the sandboxed app has no permission to access the file
+- Even though you have the entitlement, you must explicitly claim access for each user-selected file
+
+## The Solution
+
+### 1. Security-Scoped Access Wrapper
+
+We created a RAII wrapper class `MacSandboxSecurityScopedAccess` (in `utility_mac_sandbox.h/mm`) that:
+
+- Automatically calls `startAccessingSecurityScopedResource()` in the constructor
+- Automatically calls `stopAccessingSecurityScopedResource()` in the destructor
+- Uses unique_ptr for exception safety
+- Provides `isValid()` to check if access was successfully obtained
+
+### 2. Usage Pattern
+
+```cpp
+#ifdef Q_OS_MACOS
+#include "utility_mac_sandbox.h"
+#endif
+
+void MyClass::saveFile()
+{
+    const auto fileUrl = QFileDialog::getSaveFileUrl(
+        this,
+        tr("Save File"),
+        QUrl::fromLocalFile(QDir::homePath()),
+        tr("Text Files (*.txt)")
+    );
+
+    if (fileUrl.isEmpty()) {
+        return;
+    }
+
+#ifdef Q_OS_MACOS
+    // Acquire security-scoped access for the user-selected file
+    auto scopedAccess = Utility::MacSandboxSecurityScopedAccess::create(fileUrl);
+
+    if (!scopedAccess->isValid()) {
+        // Handle error - access could not be obtained
+        QMessageBox::critical(this, tr("Error"), tr("Could not access file"));
+        return;
+    }
+    // scopedAccess will automatically release when it goes out of scope
+#endif
+
+    // Now you can safely access the file
+    QFile file(fileUrl.toLocalFile());
+    if (file.open(QIODevice::WriteOnly)) {
+        // Write to file...
+    }
+}
+```
+
+### 3. Required Entitlements
+
+In `admin/osx/macosx.entitlements.cmake`, ensure you have:
+
+```xml
+<key>com.apple.security.app-sandbox</key>
+<true/>
+<key>com.apple.security.files.user-selected.read-write</key>
+<true/>
+```
+
+## Key Requirements for Qt + macOS Sandbox
+
+### 1. Use QFileDialog URL-based Methods
+
+Always use the URL-based variants of QFileDialog methods:
+- ✅ `QFileDialog::getSaveFileUrl()`
+- ✅ `QFileDialog::getOpenFileUrl()`
+- ✅ `QFileDialog::getOpenFileUrls()`
+- ❌ `QFileDialog::getSaveFileName()` - returns QString, not security-scoped
+- ❌ `QFileDialog::getOpenFileName()` - returns QString, not security-scoped
+
+### 2. Wrap File Access with Security Scoping
+
+```cpp
+#ifdef Q_OS_MACOS
+auto scopedAccess = Utility::MacSandboxSecurityScopedAccess::create(fileUrl);
+if (!scopedAccess->isValid()) {
+    // Handle error
+    return;
+}
+#endif
+// Access file here
+// scopedAccess releases automatically when going out of scope
+```
+
+### 3. Handle Scope Lifetime Correctly
+
+The security-scoped access must remain valid for the entire duration of file access:
+
+```cpp
+// ✅ CORRECT - scopedAccess lives until after file operations
+#ifdef Q_OS_MACOS
+auto scopedAccess = Utility::MacSandboxSecurityScopedAccess::create(fileUrl);
+if (!scopedAccess->isValid()) {
+    return;
+}
+#endif
+
+QFile file(fileUrl.toLocalFile());
+file.open(QIODevice::WriteOnly);
+file.write(data);
+file.close();
+// scopedAccess destructor called here
+
+// ❌ WRONG - scopedAccess destroyed before file operations
+#ifdef Q_OS_MACOS
+{
+    auto scopedAccess = Utility::MacSandboxSecurityScopedAccess::create(fileUrl);
+    if (!scopedAccess->isValid()) {
+        return;
+    }
+} // scopedAccess destroyed here!
+#endif
+
+QFile file(fileUrl.toLocalFile());  // This will fail!
+file.open(QIODevice::WriteOnly);    // No longer have access
+```
+
+### 4. Consider All File Operations
+
+This applies to ANY file operation on user-selected files:
+- Reading files
+- Writing files
+- Creating archives/zip files
+- Copying files
+- Moving files
+- Checking file existence/permissions
+
+## Common Pitfalls
+
+### 1. Using QString-based paths instead of QUrl
+
+```cpp
+// ❌ WRONG - loses security-scoped bookmark
+QString path = QFileDialog::getSaveFileName(...);
+
+// ✅ CORRECT - preserves security-scoped bookmark
+QUrl url = QFileDialog::getSaveFileUrl(...);
+```
+
+### 2. Converting QUrl too early
+
+```cpp
+// ❌ WRONG - converts to string before starting access
+QUrl url = QFileDialog::getSaveFileUrl(...);
+QString path = url.toLocalFile();  // Loses security scope!
+#ifdef Q_OS_MACOS
+auto access = Utility::MacSandboxSecurityScopedAccess::create(QUrl::fromLocalFile(path));  // Won't work
+#endif
+
+// ✅ CORRECT - start access before conversion
+QUrl url = QFileDialog::getSaveFileUrl(...);
+#ifdef Q_OS_MACOS
+auto access = Utility::MacSandboxSecurityScopedAccess::create(url);  // Works!
+#endif
+QString path = url.toLocalFile();
+```
+
+### 3. Forgetting to check isValid()
+
+```cpp
+// ❌ RISKY - doesn't check if access was obtained
+auto scopedAccess = Utility::MacSandboxSecurityScopedAccess::create(fileUrl);
+QFile file(fileUrl.toLocalFile());  // Might fail silently
+
+// ✅ CORRECT - always check validity
+auto scopedAccess = Utility::MacSandboxSecurityScopedAccess::create(fileUrl);
+if (!scopedAccess->isValid()) {
+    // Show error to user
+    return;
+}
+QFile file(fileUrl.toLocalFile());  // Now safe to use
+```
+
+## Testing Sandbox Behavior
+
+To test if your app properly handles sandbox restrictions:
+
+1. **Build with proper entitlements**: Ensure the app is codesigned with the entitlements file
+2. **Test file operations**: Try to save/open files in various locations
+3. **Check Console.app**: Look for sandbox violation messages like:
+   ```
+   Sandbox: MyApp(12345) deny(1) file-write-create /Users/...
+   ```
+4. **Test without access calls**: Temporarily remove the security-scoped access calls to verify they're needed
+
+## References
+
+- [Apple Documentation: App Sandbox](https://developer.apple.com/documentation/security/app_sandbox)
+- [Apple Documentation: Security-Scoped Bookmarks](https://developer.apple.com/documentation/foundation/nsurl/1417051-startaccessingsecurityscopedreso)
+- [Qt Documentation: QFileDialog](https://doc.qt.io/qt-6/qfiledialog.html)
+
+## Files Modified
+
+- `src/common/utility_mac_sandbox.h` - Header for security-scoped access wrapper
+- `src/common/utility_mac_sandbox.mm` - Implementation using Objective-C++
+- `src/common/common.cmake` - Added new files to build system
+- `src/gui/generalsettings.cpp` - Fixed debug archive creation to use security-scoped access
+
+## Future Work
+
+Consider auditing all uses of `QFileDialog` in the codebase to ensure they:
+1. Use URL-based methods (`getSaveFileUrl`, `getOpenFileUrl`, etc.)
+2. Properly acquire security-scoped access on macOS
+3. Handle access errors gracefully

shell_integration/MacOSX/CMakeLists.txt

@@ -21,7 +21,6 @@ if(APPLE)
         "OC_OEM_SHARE_ICNS=${OC_OEM_SHARE_ICNS}"
         "OC_APPLICATION_NAME=${APPLICATION_NAME}"
         "OC_APPLICATION_REV_DOMAIN=${APPLICATION_REV_DOMAIN}"
-        "OC_SOCKETAPI_TEAM_IDENTIFIER_PREFIX=${SOCKETAPI_TEAM_IDENTIFIER_PREFIX}"
         COMMENT building Mac Overlay icons
         VERBATIM)
 
@@ -34,7 +33,6 @@ if(APPLE)
             "OC_APPLICATION_VENDOR=${APPLICATION_VENDOR}"
             "OC_APPLICATION_NAME=${APPLICATION_NAME}"
             "OC_APPLICATION_REV_DOMAIN=${APPLICATION_REV_DOMAIN}"
-            "OC_SOCKETAPI_TEAM_IDENTIFIER_PREFIX=${SOCKETAPI_TEAM_IDENTIFIER_PREFIX}"
             COMMENT building macOS File Provider extension
             VERBATIM)
 
@@ -46,7 +44,6 @@ if(APPLE)
             "OC_APPLICATION_VENDOR=${APPLICATION_VENDOR}"
             "OC_APPLICATION_NAME=${APPLICATION_NAME}"
             "OC_APPLICATION_REV_DOMAIN=${APPLICATION_REV_DOMAIN}"
-            "OC_SOCKETAPI_TEAM_IDENTIFIER_PREFIX=${SOCKETAPI_TEAM_IDENTIFIER_PREFIX}"
             DEPENDS mac_fileproviderplugin
             COMMENT building macOS File Provider UI extension
             VERBATIM)

shell_integration/MacOSX/NextcloudIntegration/.gitignore

@@ -2,6 +2,3 @@
 # SPDX-License-Identifier: GPL-2.0-or-later
 
 DerivedData
-
-# exception
-!NextcloudDev/Build.xcconfig.template

shell_integration/MacOSX/NextcloudIntegration/FileProviderExt/FileProviderExt.entitlements

@@ -6,7 +6,7 @@
 	<true/>
 	<key>com.apple.security.application-groups</key>
 	<array>
-		<string>$(OC_SOCKETAPI_TEAM_IDENTIFIER_PREFIX)$(OC_APPLICATION_REV_DOMAIN)</string>
+		<string>$(DEVELOPMENT_TEAM).$(OC_APPLICATION_REV_DOMAIN)</string>
 	</array>
 	<key>com.apple.security.network.client</key>
 	<true/>

shell_integration/MacOSX/NextcloudIntegration/FileProviderExt/FileProviderExtension.swift

@@ -21,21 +21,21 @@ import OSLog
     ///
     let ncKit: NextcloudKit
 
-    let appGroupIdentifier = Bundle.main.object(forInfoDictionaryKey: "SocketApiPrefix") as? String
     var ncAccount: Account?
     var dbManager: FilesDatabaseManager?
     var changeObserver: RemoteChangeObserver?
     var ignoredFiles: IgnoredFilesMatcher?
     lazy var ncKitBackground = NKBackground(nkCommonInstance: ncKit.nkCommonInstance)
+
     lazy var socketClient: LocalSocketClient? = {
-        guard let containerUrl = pathForAppGroupContainer() else {
+        guard let containerUrl = FileManager.default.applicationGroupContainer() else {
             logger.fault("Won't start socket client, no container URL available!")
             return nil;
         }
 
-        let socketPath = containerUrl.appendingPathComponent(
-            ".fileprovidersocket", conformingTo: .archive)
+        let socketPath = containerUrl.appendingPathComponent("fps", conformingTo: .archive)
         let lineProcessor = FileProviderSocketLineProcessor(delegate: self, log: log)
+
         return LocalSocketClient(socketPath: socketPath.path, lineProcessor: lineProcessor)
     }()