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 "storage/browser/fileapi/external_mount_points.h"
  21 #include "storage/browser/fileapi/file_permission_policy.h"
  22 #include "storage/browser/fileapi/file_system_backend.h"
  23 #include "storage/browser/fileapi/file_system_context.h"
  24 #include "storage/browser/fileapi/file_system_operation_runner.h"
  25 #include "storage/browser/fileapi/file_system_options.h"
  26 #include "storage/browser/quota/quota_manager.h"
  27 #include "url/url_constants.h"
  28
  29 namespace content {
  30
  31 namespace {
  32
  33 using storage::FileSystemOptions;
  34
  35 FileSystemOptions CreateBrowserFileSystemOptions(bool is_incognito) {
  36   FileSystemOptions::ProfileMode profile_mode =
  37       is_incognito ? FileSystemOptions::PROFILE_MODE_INCOGNITO
  38                    : FileSystemOptions::PROFILE_MODE_NORMAL;
  39   std::vector<std::string> additional_allowed_schemes;
  40   GetContentClient()->browser()->GetAdditionalAllowedSchemesForFileSystem(
  41       &additional_allowed_schemes);
  42   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
  43           switches::kAllowFileAccessFromFiles)) {
  44     additional_allowed_schemes.push_back(url::kFileScheme);
  45   }
  46   return FileSystemOptions(profile_mode, additional_allowed_schemes, NULL);
  47 }
  48
  49 }  // namespace
  50
  51 scoped_refptr<storage::FileSystemContext> CreateFileSystemContext(
  52     BrowserContext* browser_context,
  53     const base::FilePath& profile_path,
  54     bool is_incognito,
  55     storage::QuotaManagerProxy* quota_manager_proxy) {
  56   base::SequencedWorkerPool* pool = 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<storage::FileSystemBackend> additional_backends;
  64   GetContentClient()->browser()->GetAdditionalFileSystemBackends(
  65       browser_context,
  66       profile_path,
  67       &additional_backends);
  68
  69   // Set up the auto mount handlers for url requests.
  70   std::vector<storage::URLRequestAutoMountHandler>
  71       url_request_auto_mount_handlers;
  72   GetContentClient()->browser()->GetURLRequestAutoMountHandlers(
  73       &url_request_auto_mount_handlers);
  74
  75   scoped_refptr<storage::FileSystemContext> file_system_context =
  76       new storage::FileSystemContext(
  77           BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO).get(),
  78           file_task_runner.get(),
  79           BrowserContext::GetMountPoints(browser_context),
  80           browser_context->GetSpecialStoragePolicy(),
  81           quota_manager_proxy,
  82           additional_backends.Pass(),
  83           url_request_auto_mount_handlers,
  84           profile_path,
  85           CreateBrowserFileSystemOptions(is_incognito));
  86
  87   std::vector<storage::FileSystemType> types;
  88   file_system_context->GetFileSystemTypes(&types);
  89   for (size_t i = 0; i < types.size(); ++i) {
  90     ChildProcessSecurityPolicyImpl::GetInstance()
  91         ->RegisterFileSystemPermissionPolicy(
  92             types[i],
  93             storage::FileSystemContext::GetPermissionPolicy(types[i]));
  94   }
  95
  96   return file_system_context;
  97 }
  98
  99 bool FileSystemURLIsValid(storage::FileSystemContext* context,
 100                           const storage::FileSystemURL& url) {
 101   if (!url.is_valid())
 102     return false;
 103
 104   return context->GetFileSystemBackend(url.type()) != NULL;
 105 }
 106
 107 void SyncGetPlatformPath(storage::FileSystemContext* context,
 108                          int process_id,
 109                          const GURL& path,
 110                          base::FilePath* platform_path) {
 111   DCHECK(context->default_file_task_runner()->
 112          RunsTasksOnCurrentThread());
 113   DCHECK(platform_path);
 114   *platform_path = base::FilePath();
 115   storage::FileSystemURL url(context->CrackURL(path));
 116   if (!FileSystemURLIsValid(context, url))
 117     return;
 118
 119   // Make sure if this file is ok to be read (in the current architecture
 120   // which means roughly same as the renderer is allowed to get the platform
 121   // path to the file).
 122   ChildProcessSecurityPolicyImpl* policy =
 123       ChildProcessSecurityPolicyImpl::GetInstance();
 124   if (!policy->CanReadFileSystemFile(process_id, url))
 125     return;
 126
 127   context->operation_runner()->SyncGetPlatformPath(url, platform_path);
 128
 129   // The path is to be attached to URLLoader so we grant read permission
 130   // for the file. (We need to check first because a parent directory may
 131   // already have the permissions and we don't need to grant it to the file.)
 132   if (!policy->CanReadFile(process_id, *platform_path))
 133     policy->GrantReadFile(process_id, *platform_path);
 134 }
 135
 136 }  // namespace content