File system API: whitelist the Downloads dir on Chrome OS.

chrome/browser/extensions/api/file_system/file_system_api.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/extensions/api/file_system/file_system_api.h"
 
 #include "apps/saved_files_service.h"
 #include "base/bind.h"
 #include "base/file_util.h"
 #include "base/files/file_path.h"
@@ skipping 55 matching lines @@
 namespace file_system = extensions::api::file_system;
 namespace ChooseEntry = file_system::ChooseEntry;
 
 namespace {
 
 const int kBlacklistedPaths[] = {
   chrome::DIR_APP,
   chrome::DIR_USER_DATA,
 };
 
+#if defined(OS_CHROMEOS)
+// On Chrome OS, the default downloads directory is a subdirectory of user data
+// directory, and should be whitelisted.
+const int kWhitelistedPaths[] = {
+  chrome::DIR_DEFAULT_DOWNLOADS_SAFE,
+};
+#endif
+
 #if defined(OS_MACOSX)
 // Retrieves the localized display name for the base name of the given path.
 // If the path is not localized, this will just return the base name.
 std::string GetDisplayBaseName(const base::FilePath& path) {
   base::mac::ScopedCFTypeRef<CFURLRef> url(
       CFURLCreateFromFileSystemRepresentation(
           NULL,
           (const UInt8*)path.value().c_str(),
           path.value().length(),
           true));
@@ skipping 118 matching lines @@
 
 bool DoCheckWritableFile(const base::FilePath& path,
                          const base::FilePath& extension_directory) {
   // Don't allow links.
   if (file_util::PathExists(path) && file_util::IsLink(path))
     return false;
 
   if (extension_directory == path || extension_directory.IsParent(path))
     return false;
 
-  for (size_t i = 0; i < arraysize(kBlacklistedPaths); i++) {
-    base::FilePath blacklisted_path;
-    if (PathService::Get(kBlacklistedPaths[i], &blacklisted_path) &&
-        (blacklisted_path == path || blacklisted_path.IsParent(path))) {
-      return false;
+  bool is_whitelisted_path = false;
+
+#if defined(OS_CHROMEOS)
+  for (size_t i = 0; i < arraysize(kWhitelistedPaths); i++) {
+    base::FilePath whitelisted_path;
+    if (PathService::Get(kWhitelistedPaths[i], &whitelisted_path) &&
+        (whitelisted_path == path || whitelisted_path.IsParent(path))) {
+      is_whitelisted_path = true;
+      break;
+    }
+  }
+#endif
+
+  if (!is_whitelisted_path) {
+    for (size_t i = 0; i < arraysize(kBlacklistedPaths); i++) {
+      base::FilePath blacklisted_path;
+      if (PathService::Get(kBlacklistedPaths[i], &blacklisted_path) &&
+          (blacklisted_path == path || blacklisted_path.IsParent(path))) {
+        return false;
+      }
     }
   }
 
   // Create the file if it doesn't already exist.
   base::PlatformFileError error = base::PLATFORM_FILE_OK;
   int creation_flags = base::PLATFORM_FILE_CREATE |
                        base::PLATFORM_FILE_READ |
                        base::PLATFORM_FILE_WRITE;
   base::PlatformFile file = base::CreatePlatformFile(path, creation_flags,
                                                      NULL, &error);
@@ skipping 589 matching lines @@
     // ID that was passed to restoreEntry.
     RegisterFileSystemAndSendResponseWithIdOverride(
         file_entry->path,
         file_entry->writable ? WRITABLE : READ_ONLY,
         file_entry->id);
   }
   return true;
 }
 
 }  // namespace extensions