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_context.h"
  25 #include "webkit/browser/fileapi/file_system_operation_runner.h"
  26 #include "webkit/browser/fileapi/file_system_options.h"
  27 #include "webkit/browser/quota/quota_manager.h"
  28
  29 namespace content {
  30
  31 namespace {
  32
  33 using fileapi::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 (CommandLine::ForCurrentProcess()->HasSwitch(
  43           switches::kAllowFileAccessFromFiles)) {
  44     additional_allowed_schemes.push_back(kFileScheme);
  45   }
  46   return FileSystemOptions(profile_mode, additional_allowed_schemes, NULL);
  47 }
  48
  49 }  // namespace
  50
  51 scoped_refptr<fileapi::FileSystemContext> CreateFileSystemContext(
  52     BrowserContext* browser_context,
  53     const base::FilePath& profile_path,
  54     bool is_incognito,
  55     quota::QuotaManagerProxy* quota_manager_proxy) {
  56
  57   base::SequencedWorkerPool* pool = BrowserThread::GetBlockingPool();
  58   scoped_refptr<base::SequencedTaskRunner> file_task_runner =
  59       pool->GetSequencedTaskRunnerWithShutdownBehavior(
  60           pool->GetNamedSequenceToken("FileAPI"),
  61           base::SequencedWorkerPool::SKIP_ON_SHUTDOWN);
  62
  63   // Setting up additional filesystem backends.
  64   ScopedVector<fileapi::FileSystemBackend> additional_backends;
  65   GetContentClient()->browser()->GetAdditionalFileSystemBackends(
  66       browser_context,
  67       profile_path,
  68       &additional_backends);
  69
  70   // Set up the auto mount handlers for url requests.
  71   std::vector<fileapi::URLRequestAutoMountHandler>
  72       url_request_auto_mount_handlers;
  73   GetContentClient()->browser()->GetURLRequestAutoMountHandlers(
  74       &url_request_auto_mount_handlers);
  75
  76   scoped_refptr<fileapi::FileSystemContext> file_system_context =
  77       new fileapi::FileSystemContext(
  78           BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO).get(),
  79           file_task_runner.get(),
  80           BrowserContext::GetMountPoints(browser_context),
  81           browser_context->GetSpecialStoragePolicy(),
  82           quota_manager_proxy,
  83           additional_backends.Pass(),
  84           url_request_auto_mount_handlers,
  85           profile_path,
  86           CreateBrowserFileSystemOptions(is_incognito));
  87
  88   std::vector<fileapi::FileSystemType> types;
  89   file_system_context->GetFileSystemTypes(&types);
  90   for (size_t i = 0; i < types.size(); ++i) {
  91     ChildProcessSecurityPolicyImpl::GetInstance()->
  92         RegisterFileSystemPermissionPolicy(
  93             types[i],
  94             fileapi::FileSystemContext::GetPermissionPolicy(types[i]));
  95   }
  96
  97   return file_system_context;
  98 }
  99
 100 bool FileSystemURLIsValid(
 101     fileapi::FileSystemContext* context,
 102     const fileapi::FileSystemURL& url) {
 103   if (!url.is_valid())
 104     return false;
 105
 106   return context->GetFileSystemBackend(url.type()) != NULL;
 107 }
 108
 109 void SyncGetPlatformPath(fileapi::FileSystemContext* context,
 110                          int process_id,
 111                          const GURL& path,
 112                          base::FilePath* platform_path) {
 113   DCHECK(context->default_file_task_runner()->
 114          RunsTasksOnCurrentThread());
 115   DCHECK(platform_path);
 116   *platform_path = base::FilePath();
 117   fileapi::FileSystemURL url(context->CrackURL(path));
 118   if (!FileSystemURLIsValid(context, url))
 119     return;
 120
 121   // Make sure if this file is ok to be read (in the current architecture
 122   // which means roughly same as the renderer is allowed to get the platform
 123   // path to the file).
 124   ChildProcessSecurityPolicyImpl* policy =
 125       ChildProcessSecurityPolicyImpl::GetInstance();
 126   if (!policy->CanReadFileSystemFile(process_id, url))
 127     return;
 128
 129   context->operation_runner()->SyncGetPlatformPath(url, platform_path);
 130
 131   // The path is to be attached to URLLoader so we grant read permission
 132   // for the file. (We need to check first because a parent directory may
 133   // already have the permissions and we don't need to grant it to the file.)
 134   if (!policy->CanReadFile(process_id, *platform_path))
 135     policy->GrantReadFile(process_id, *platform_path);
 136 }
 137
 138 }  // namespace content