src/chrome/browser/download/download_request_limiter.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 "chrome/browser/download/download_request_limiter.h"
   6
   7 #include "base/bind.h"
   8 #include "base/stl_util.h"
   9 #include "chrome/browser/content_settings/host_content_settings_map.h"
  10 #include "chrome/browser/content_settings/tab_specific_content_settings.h"
  11 #include "chrome/browser/download/download_permission_request.h"
  12 #include "chrome/browser/download/download_request_infobar_delegate.h"
  13 #include "chrome/browser/infobars/infobar_service.h"
  14 #include "chrome/browser/profiles/profile.h"
  15 #include "chrome/browser/tab_contents/tab_util.h"
  16 #include "chrome/browser/ui/website_settings/permission_bubble_manager.h"
  17 #include "content/public/browser/browser_context.h"
  18 #include "content/public/browser/browser_thread.h"
  19 #include "content/public/browser/navigation_controller.h"
  20 #include "content/public/browser/navigation_entry.h"
  21 #include "content/public/browser/notification_source.h"
  22 #include "content/public/browser/notification_types.h"
  23 #include "content/public/browser/render_process_host.h"
  24 #include "content/public/browser/resource_dispatcher_host.h"
  25 #include "content/public/browser/web_contents.h"
  26 #include "content/public/browser/web_contents_delegate.h"
  27 #include "url/gurl.h"
  28
  29 using content::BrowserThread;
  30 using content::NavigationController;
  31 using content::NavigationEntry;
  32
  33 // TabDownloadState ------------------------------------------------------------
  34
  35 DownloadRequestLimiter::TabDownloadState::TabDownloadState(
  36     DownloadRequestLimiter* host,
  37     content::WebContents* contents,
  38     content::WebContents* originating_web_contents)
  39     : content::WebContentsObserver(contents),
  40       web_contents_(contents),
  41       host_(host),
  42       status_(DownloadRequestLimiter::ALLOW_ONE_DOWNLOAD),
  43       download_count_(0),
  44       factory_(this) {
  45   content::Source<NavigationController> notification_source(
  46       &contents->GetController());
  47   registrar_.Add(this, content::NOTIFICATION_NAV_ENTRY_PENDING,
  48                  notification_source);
  49   NavigationEntry* active_entry = originating_web_contents ?
  50       originating_web_contents->GetController().GetActiveEntry() :
  51       contents->GetController().GetActiveEntry();
  52   if (active_entry)
  53     initial_page_host_ = active_entry->GetURL().host();
  54 }
  55
  56 DownloadRequestLimiter::TabDownloadState::~TabDownloadState() {
  57   // We should only be destroyed after the callbacks have been notified.
  58   DCHECK(callbacks_.empty());
  59
  60   // And we should have invalidated the back pointer.
  61   DCHECK(!factory_.HasWeakPtrs());
  62 }
  63
  64 void DownloadRequestLimiter::TabDownloadState::AboutToNavigateRenderView(
  65     content::RenderViewHost* render_view_host) {
  66   switch (status_) {
  67     case ALLOW_ONE_DOWNLOAD:
  68     case PROMPT_BEFORE_DOWNLOAD:
  69       // When the user reloads the page without responding to the infobar, they
  70       // are expecting DownloadRequestLimiter to behave as if they had just
  71       // initially navigated to this page. See http://crbug.com/171372
  72       NotifyCallbacks(false);
  73       host_->Remove(this, web_contents());
  74       // WARNING: We've been deleted.
  75       break;
  76     case DOWNLOADS_NOT_ALLOWED:
  77     case ALLOW_ALL_DOWNLOADS:
  78       // Don't drop this information. The user has explicitly said that they
  79       // do/don't want downloads from this host.  If they accidentally Accepted
  80       // or Canceled, tough luck, they don't get another chance. They can copy
  81       // the URL into a new tab, which will make a new DownloadRequestLimiter.
  82       // See also the initial_page_host_ logic in Observe() for
  83       // NOTIFICATION_NAV_ENTRY_PENDING.
  84       break;
  85     default:
  86       NOTREACHED();
  87   }
  88 }
  89
  90 void DownloadRequestLimiter::TabDownloadState::DidGetUserGesture() {
  91   if (is_showing_prompt()) {
  92     // Don't change the state if the user clicks on the page somewhere.
  93     return;
  94   }
  95
  96   bool promptable = (InfoBarService::FromWebContents(web_contents()) != NULL);
  97   if (PermissionBubbleManager::Enabled()) {
  98     promptable =
  99         (PermissionBubbleManager::FromWebContents(web_contents()) != NULL);
 100   }
 101
 102   // See PromptUserForDownload(): if there's no InfoBarService, then
 103   // DOWNLOADS_NOT_ALLOWED is functionally equivalent to PROMPT_BEFORE_DOWNLOAD.
 104   if ((status_ != DownloadRequestLimiter::ALLOW_ALL_DOWNLOADS) &&
 105       (!promptable ||
 106        (status_ != DownloadRequestLimiter::DOWNLOADS_NOT_ALLOWED))) {
 107     // Revert to default status.
 108     host_->Remove(this, web_contents());
 109     // WARNING: We've been deleted.
 110   }
 111 }
 112
 113 void DownloadRequestLimiter::TabDownloadState::WebContentsDestroyed() {
 114   // Tab closed, no need to handle closing the dialog as it's owned by the
 115   // WebContents.
 116
 117   NotifyCallbacks(false);
 118   host_->Remove(this, web_contents());
 119   // WARNING: We've been deleted.
 120 }
 121
 122 void DownloadRequestLimiter::TabDownloadState::PromptUserForDownload(
 123     const DownloadRequestLimiter::Callback& callback) {
 124   callbacks_.push_back(callback);
 125   DCHECK(web_contents_);
 126   if (is_showing_prompt())
 127     return;
 128
 129   if (PermissionBubbleManager::Enabled()) {
 130     PermissionBubbleManager* bubble_manager =
 131         PermissionBubbleManager::FromWebContents(web_contents_);
 132     if (bubble_manager) {
 133       bubble_manager->AddRequest(new DownloadPermissionRequest(
 134           factory_.GetWeakPtr()));
 135     } else {
 136       Cancel();
 137     }
 138     return;
 139   }
 140
 141   DownloadRequestInfoBarDelegate::Create(
 142       InfoBarService::FromWebContents(web_contents_), factory_.GetWeakPtr());
 143 }
 144
 145 void DownloadRequestLimiter::TabDownloadState::SetContentSetting(
 146     ContentSetting setting) {
 147   if (!web_contents_)
 148     return;
 149   HostContentSettingsMap* settings =
 150     DownloadRequestLimiter::GetContentSettings(web_contents_);
 151   ContentSettingsPattern pattern(
 152       ContentSettingsPattern::FromURL(web_contents_->GetURL()));
 153   if (!settings || !pattern.IsValid())
 154     return;
 155   settings->SetContentSetting(
 156       pattern,
 157       ContentSettingsPattern::Wildcard(),
 158       CONTENT_SETTINGS_TYPE_AUTOMATIC_DOWNLOADS,
 159       std::string(),
 160       setting);
 161 }
 162
 163 void DownloadRequestLimiter::TabDownloadState::Cancel() {
 164   SetContentSetting(CONTENT_SETTING_BLOCK);
 165   NotifyCallbacks(false);
 166 }
 167
 168 void DownloadRequestLimiter::TabDownloadState::CancelOnce() {
 169   NotifyCallbacks(false);
 170 }
 171
 172 void DownloadRequestLimiter::TabDownloadState::Accept() {
 173   SetContentSetting(CONTENT_SETTING_ALLOW);
 174   NotifyCallbacks(true);
 175 }
 176
 177 DownloadRequestLimiter::TabDownloadState::TabDownloadState()
 178     : web_contents_(NULL),
 179       host_(NULL),
 180       status_(DownloadRequestLimiter::ALLOW_ONE_DOWNLOAD),
 181       download_count_(0),
 182       factory_(this) {
 183 }
 184
 185 bool DownloadRequestLimiter::TabDownloadState::is_showing_prompt() const {
 186   return factory_.HasWeakPtrs();
 187 }
 188
 189 void DownloadRequestLimiter::TabDownloadState::Observe(
 190     int type,
 191     const content::NotificationSource& source,
 192     const content::NotificationDetails& details) {
 193   DCHECK_EQ(content::NOTIFICATION_NAV_ENTRY_PENDING, type);
 194   content::NavigationController* controller = &web_contents()->GetController();
 195   DCHECK_EQ(controller, content::Source<NavigationController>(source).ptr());
 196
 197   // NOTE: Resetting state on a pending navigate isn't ideal. In particular it
 198   // is possible that queued up downloads for the page before the pending
 199   // navigation will be delivered to us after we process this request. If this
 200   // happens we may let a download through that we shouldn't have. But this is
 201   // rather rare, and it is difficult to get 100% right, so we don't deal with
 202   // it.
 203   NavigationEntry* entry = controller->GetPendingEntry();
 204   if (!entry)
 205     return;
 206
 207   // Redirects don't count.
 208   if (ui::PageTransitionIsRedirect(entry->GetTransitionType()))
 209     return;
 210
 211   if (status_ == DownloadRequestLimiter::ALLOW_ALL_DOWNLOADS ||
 212       status_ == DownloadRequestLimiter::DOWNLOADS_NOT_ALLOWED) {
 213     // User has either allowed all downloads or canceled all downloads. Only
 214     // reset the download state if the user is navigating to a different host
 215     // (or host is empty).
 216     if (!initial_page_host_.empty() && !entry->GetURL().host().empty() &&
 217         entry->GetURL().host() == initial_page_host_)
 218       return;
 219   }
 220
 221   NotifyCallbacks(false);
 222   host_->Remove(this, web_contents());
 223 }
 224
 225 void DownloadRequestLimiter::TabDownloadState::NotifyCallbacks(bool allow) {
 226   set_download_status(allow ?
 227       DownloadRequestLimiter::ALLOW_ALL_DOWNLOADS :
 228       DownloadRequestLimiter::DOWNLOADS_NOT_ALLOWED);
 229   std::vector<DownloadRequestLimiter::Callback> callbacks;
 230   bool change_status = false;
 231
 232   // Selectively send first few notifications only if number of downloads exceed
 233   // kMaxDownloadsAtOnce. In that case, we also retain the infobar instance and
 234   // don't close it. If allow is false, we send all the notifications to cancel
 235   // all remaining downloads and close the infobar.
 236   if (!allow || (callbacks_.size() < kMaxDownloadsAtOnce)) {
 237     // Null the generated weak pointer so we don't get notified again.
 238     factory_.InvalidateWeakPtrs();
 239     callbacks.swap(callbacks_);
 240   } else {
 241     std::vector<DownloadRequestLimiter::Callback>::iterator start, end;
 242     start = callbacks_.begin();
 243     end = callbacks_.begin() + kMaxDownloadsAtOnce;
 244     callbacks.assign(start, end);
 245     callbacks_.erase(start, end);
 246     change_status = true;
 247   }
 248
 249   for (size_t i = 0; i < callbacks.size(); ++i)
 250     host_->ScheduleNotification(callbacks[i], allow);
 251
 252   if (change_status)
 253     set_download_status(DownloadRequestLimiter::PROMPT_BEFORE_DOWNLOAD);
 254 }
 255
 256 // DownloadRequestLimiter ------------------------------------------------------
 257
 258 HostContentSettingsMap* DownloadRequestLimiter::content_settings_ = NULL;
 259
 260 void DownloadRequestLimiter::SetContentSettingsForTesting(
 261     HostContentSettingsMap* content_settings) {
 262   content_settings_ = content_settings;
 263 }
 264
 265 DownloadRequestLimiter::DownloadRequestLimiter()
 266     : factory_(this) {
 267 }
 268
 269 DownloadRequestLimiter::~DownloadRequestLimiter() {
 270   // All the tabs should have closed before us, which sends notification and
 271   // removes from state_map_. As such, there should be no pending callbacks.
 272   DCHECK(state_map_.empty());
 273 }
 274
 275 DownloadRequestLimiter::DownloadStatus
 276 DownloadRequestLimiter::GetDownloadStatus(content::WebContents* web_contents) {
 277   TabDownloadState* state = GetDownloadState(web_contents, NULL, false);
 278   return state ? state->download_status() : ALLOW_ONE_DOWNLOAD;
 279 }
 280
 281 void DownloadRequestLimiter::CanDownloadOnIOThread(
 282     int render_process_host_id,
 283     int render_view_id,
 284     const GURL& url,
 285     const std::string& request_method,
 286     const Callback& callback) {
 287   // This is invoked on the IO thread. Schedule the task to run on the UI
 288   // thread so that we can query UI state.
 289   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 290   BrowserThread::PostTask(
 291       BrowserThread::UI, FROM_HERE,
 292       base::Bind(&DownloadRequestLimiter::CanDownload, this,
 293                  render_process_host_id, render_view_id, url,
 294                  request_method, callback));
 295 }
 296
 297 DownloadRequestLimiter::TabDownloadState*
 298 DownloadRequestLimiter::GetDownloadState(
 299     content::WebContents* web_contents,
 300     content::WebContents* originating_web_contents,
 301     bool create) {
 302   DCHECK(web_contents);
 303   StateMap::iterator i = state_map_.find(web_contents);
 304   if (i != state_map_.end())
 305     return i->second;
 306
 307   if (!create)
 308     return NULL;
 309
 310   TabDownloadState* state =
 311       new TabDownloadState(this, web_contents, originating_web_contents);
 312   state_map_[web_contents] = state;
 313   return state;
 314 }
 315
 316 void DownloadRequestLimiter::CanDownload(int render_process_host_id,
 317                                          int render_view_id,
 318                                          const GURL& url,
 319                                          const std::string& request_method,
 320                                          const Callback& callback) {
 321   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 322
 323   content::WebContents* originating_contents =
 324       tab_util::GetWebContentsByID(render_process_host_id, render_view_id);
 325   if (!originating_contents) {
 326     // The WebContents was closed, don't allow the download.
 327     ScheduleNotification(callback, false);
 328     return;
 329   }
 330
 331   if (!originating_contents->GetDelegate()) {
 332     ScheduleNotification(callback, false);
 333     return;
 334   }
 335
 336   // Note that because |originating_contents| might go away before
 337   // OnCanDownloadDecided is invoked, we look it up by |render_process_host_id|
 338   // and |render_view_id|.
 339   base::Callback<void(bool)> can_download_callback = base::Bind(
 340       &DownloadRequestLimiter::OnCanDownloadDecided,
 341       factory_.GetWeakPtr(),
 342       render_process_host_id,
 343       render_view_id,
 344       request_method,
 345       callback);
 346
 347   originating_contents->GetDelegate()->CanDownload(
 348       originating_contents->GetRenderViewHost(),
 349       url,
 350       request_method,
 351       can_download_callback);
 352 }
 353
 354 void DownloadRequestLimiter::OnCanDownloadDecided(
 355     int render_process_host_id,
 356     int render_view_id,
 357     const std::string& request_method,
 358     const Callback& orig_callback, bool allow) {
 359   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 360   content::WebContents* originating_contents =
 361       tab_util::GetWebContentsByID(render_process_host_id, render_view_id);
 362   if (!originating_contents || !allow) {
 363     ScheduleNotification(orig_callback, false);
 364     return;
 365   }
 366
 367   CanDownloadImpl(originating_contents,
 368                   request_method,
 369                   orig_callback);
 370 }
 371
 372 HostContentSettingsMap* DownloadRequestLimiter::GetContentSettings(
 373     content::WebContents* contents) {
 374   return content_settings_ ? content_settings_ : Profile::FromBrowserContext(
 375       contents->GetBrowserContext())->GetHostContentSettingsMap();
 376 }
 377
 378 void DownloadRequestLimiter::CanDownloadImpl(
 379     content::WebContents* originating_contents,
 380     const std::string& request_method,
 381     const Callback& callback) {
 382   DCHECK(originating_contents);
 383
 384   TabDownloadState* state = GetDownloadState(
 385       originating_contents, originating_contents, true);
 386   switch (state->download_status()) {
 387     case ALLOW_ALL_DOWNLOADS:
 388       if (state->download_count() && !(state->download_count() %
 389             DownloadRequestLimiter::kMaxDownloadsAtOnce))
 390         state->set_download_status(PROMPT_BEFORE_DOWNLOAD);
 391       ScheduleNotification(callback, true);
 392       state->increment_download_count();
 393       break;
 394
 395     case ALLOW_ONE_DOWNLOAD:
 396       state->set_download_status(PROMPT_BEFORE_DOWNLOAD);
 397       ScheduleNotification(callback, true);
 398       state->increment_download_count();
 399       break;
 400
 401     case DOWNLOADS_NOT_ALLOWED:
 402       ScheduleNotification(callback, false);
 403       break;
 404
 405     case PROMPT_BEFORE_DOWNLOAD: {
 406       HostContentSettingsMap* content_settings = GetContentSettings(
 407           originating_contents);
 408       ContentSetting setting = CONTENT_SETTING_ASK;
 409       if (content_settings)
 410         setting = content_settings->GetContentSetting(
 411             originating_contents->GetURL(),
 412             originating_contents->GetURL(),
 413             CONTENT_SETTINGS_TYPE_AUTOMATIC_DOWNLOADS,
 414             std::string());
 415       switch (setting) {
 416         case CONTENT_SETTING_ALLOW: {
 417           TabSpecificContentSettings* settings =
 418               TabSpecificContentSettings::FromWebContents(
 419                   originating_contents);
 420           if (settings)
 421             settings->SetDownloadsBlocked(false);
 422           ScheduleNotification(callback, true);
 423           state->increment_download_count();
 424           return;
 425         }
 426         case CONTENT_SETTING_BLOCK: {
 427           TabSpecificContentSettings* settings =
 428               TabSpecificContentSettings::FromWebContents(
 429                   originating_contents);
 430           if (settings)
 431             settings->SetDownloadsBlocked(true);
 432           ScheduleNotification(callback, false);
 433           return;
 434         }
 435         case CONTENT_SETTING_DEFAULT:
 436         case CONTENT_SETTING_ASK:
 437         case CONTENT_SETTING_SESSION_ONLY:
 438           state->PromptUserForDownload(callback);
 439           state->increment_download_count();
 440           break;
 441         case CONTENT_SETTING_NUM_SETTINGS:
 442         default:
 443           NOTREACHED();
 444           return;
 445       }
 446       break;
 447     }
 448
 449     default:
 450       NOTREACHED();
 451   }
 452 }
 453
 454 void DownloadRequestLimiter::ScheduleNotification(const Callback& callback,
 455                                                   bool allow) {
 456   BrowserThread::PostTask(
 457       BrowserThread::IO, FROM_HERE, base::Bind(callback, allow));
 458 }
 459
 460 void DownloadRequestLimiter::Remove(TabDownloadState* state,
 461                                     content::WebContents* contents) {
 462   DCHECK(ContainsKey(state_map_, contents));
 463   state_map_.erase(contents);
 464   delete state;
 465 }