content/browser/fileapi/browser_file_system_helper.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/browser/fileapi/browser_file_system_helper.h"
   6
   7 #include <string>
   8 #include <vector>
   9
  10 #include "base/command_line.h"
  11 #include "base/files/file_path.h"
  12 #include "base/sequenced_task_runner.h"
  13 #include "base/threading/sequenced_worker_pool.h"
  14 #include "content/browser/child_process_security_policy_impl.h"
  15 #include "content/public/browser/browser_context.h"
  16 #include "content/public/browser/browser_thread.h"
  17 #include "content/public/browser/content_browser_client.h"
  18 #include "content/public/common/content_client.h"
  19 #include "content/public/common/content_switches.h"
  20 #include "content/public/common/url_constants.h"
  21 #include "webkit/browser/fileapi/external_mount_points.h"
  22 #include "webkit/browser/fileapi/file_permission_policy.h"
  23 #include "webkit/browser/fileapi/file_system_backend.h"
  24 #include "webkit/browser/fileapi/file_system_operation_runner.h"
  25 #include "webkit/browser/fileapi/file_system_options.h"
  26 #include "webkit/browser/quota/quota_manager.h"
  27
  28 namespace content {
  29
  30 namespace {
  31
  32 using fileapi::FileSystemOptions;
  33
  34 FileSystemOptions CreateBrowserFileSystemOptions(bool is_incognito) {
  35   FileSystemOptions::ProfileMode profile_mode =
  36       is_incognito ? FileSystemOptions::PROFILE_MODE_INCOGNITO
  37                    : FileSystemOptions::PROFILE_MODE_NORMAL;
  38   std::vector<std::string> additional_allowed_schemes;
  39   GetContentClient()->browser()->GetAdditionalAllowedSchemesForFileSystem(
  40       &additional_allowed_schemes);
  41   if (CommandLine::ForCurrentProcess()->HasSwitch(
  42           switches::kAllowFileAccessFromFiles)) {
  43     additional_allowed_schemes.push_back(chrome::kFileScheme);
  44   }
  45   return FileSystemOptions(profile_mode, additional_allowed_schemes);
  46 }
  47
  48 }  // namespace
  49
  50 scoped_refptr<fileapi::FileSystemContext> CreateFileSystemContext(
  51     BrowserContext* browser_context,
  52     const base::FilePath& profile_path,
  53     bool is_incognito,
  54     quota::QuotaManagerProxy* quota_manager_proxy) {
  55
  56   base::SequencedWorkerPool* pool = content::BrowserThread::GetBlockingPool();
  57   scoped_refptr<base::SequencedTaskRunner> file_task_runner =
  58       pool->GetSequencedTaskRunnerWithShutdownBehavior(
  59           pool->GetNamedSequenceToken("FileAPI"),
  60           base::SequencedWorkerPool::SKIP_ON_SHUTDOWN);
  61
  62   // Setting up additional filesystem backends.
  63   ScopedVector<fileapi::FileSystemBackend> additional_backends;
  64   GetContentClient()->browser()->GetAdditionalFileSystemBackends(
  65       browser_context,
  66       profile_path,
  67       &additional_backends);
  68
  69   scoped_refptr<fileapi::FileSystemContext> file_system_context =
  70       new fileapi::FileSystemContext(
  71           BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO).get(),
  72           file_task_runner.get(),
  73           BrowserContext::GetMountPoints(browser_context),
  74           browser_context->GetSpecialStoragePolicy(),
  75           quota_manager_proxy,
  76           additional_backends.Pass(),
  77           profile_path,
  78           CreateBrowserFileSystemOptions(is_incognito));
  79
  80   std::vector<fileapi::FileSystemType> types;
  81   file_system_context->GetFileSystemTypes(&types);
  82   for (size_t i = 0; i < types.size(); ++i) {
  83     ChildProcessSecurityPolicyImpl::GetInstance()->
  84         RegisterFileSystemPermissionPolicy(
  85             types[i],
  86             fileapi::FileSystemContext::GetPermissionPolicy(types[i]));
  87   }
  88
  89   return file_system_context;
  90 }
  91
  92 bool FileSystemURLIsValid(
  93     fileapi::FileSystemContext* context,
  94     const fileapi::FileSystemURL& url) {
  95   if (!url.is_valid())
  96     return false;
  97
  98   return context->GetFileSystemBackend(url.type()) != NULL;
  99 }
 100
 101 void SyncGetPlatformPath(fileapi::FileSystemContext* context,
 102                          int process_id,
 103                          const GURL& path,
 104                          base::FilePath* platform_path) {
 105   DCHECK(context->default_file_task_runner()->
 106          RunsTasksOnCurrentThread());
 107   DCHECK(platform_path);
 108   *platform_path = base::FilePath();
 109   fileapi::FileSystemURL url(context->CrackURL(path));
 110   if (!FileSystemURLIsValid(context, url))
 111     return;
 112
 113   // Make sure if this file is ok to be read (in the current architecture
 114   // which means roughly same as the renderer is allowed to get the platform
 115   // path to the file).
 116   ChildProcessSecurityPolicyImpl* policy =
 117       ChildProcessSecurityPolicyImpl::GetInstance();
 118   if (!policy->CanReadFileSystemFile(process_id, url))
 119     return;
 120
 121   context->operation_runner()->SyncGetPlatformPath(url, platform_path);
 122
 123   // The path is to be attached to URLLoader so we grant read permission
 124   // for the file. (We need to check first because a parent directory may
 125   // already have the permissions and we don't need to grant it to the file.)
 126   if (!policy->CanReadFile(process_id, *platform_path))
 127     policy->GrantReadFile(process_id, *platform_path);
 128 }
 129
 130 }  // namespace content