content/browser/download/download_resource_handler.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/download/download_resource_handler.h"
   6
   7 #include <string>
   8
   9 #include "base/bind.h"
  10 #include "base/location.h"
  11 #include "base/logging.h"
  12 #include "base/metrics/histogram_macros.h"
  13 #include "base/metrics/sparse_histogram.h"
  14 #include "base/single_thread_task_runner.h"
  15 #include "base/strings/stringprintf.h"
  16 #include "base/thread_task_runner_handle.h"
  17 #include "content/browser/byte_stream.h"
  18 #include "content/browser/download/download_create_info.h"
  19 #include "content/browser/download/download_interrupt_reasons_impl.h"
  20 #include "content/browser/download/download_manager_impl.h"
  21 #include "content/browser/download/download_request_handle.h"
  22 #include "content/browser/download/download_stats.h"
  23 #include "content/browser/loader/resource_dispatcher_host_impl.h"
  24 #include "content/browser/loader/resource_request_info_impl.h"
  25 #include "content/public/browser/browser_thread.h"
  26 #include "content/public/browser/download_interrupt_reasons.h"
  27 #include "content/public/browser/download_item.h"
  28 #include "content/public/browser/download_manager_delegate.h"
  29 #include "content/public/browser/navigation_entry.h"
  30 #include "content/public/browser/power_save_blocker.h"
  31 #include "content/public/browser/web_contents.h"
  32 #include "content/public/common/resource_response.h"
  33 #include "net/base/io_buffer.h"
  34 #include "net/base/net_errors.h"
  35 #include "net/http/http_response_headers.h"
  36 #include "net/http/http_status_code.h"
  37 #include "net/url_request/url_request_context.h"
  38
  39 namespace content {
  40
  41 struct DownloadResourceHandler::DownloadTabInfo {
  42   GURL tab_url;
  43   GURL tab_referrer_url;
  44 };
  45
  46 namespace {
  47
  48 void CallStartedCBOnUIThread(
  49     const DownloadUrlParameters::OnStartedCallback& started_cb,
  50     DownloadItem* item,
  51     DownloadInterruptReason interrupt_reason) {
  52   DCHECK_CURRENTLY_ON(BrowserThread::UI);
  53
  54   if (started_cb.is_null())
  55     return;
  56   started_cb.Run(item, interrupt_reason);
  57 }
  58
  59 // Static function in order to prevent any accidental accesses to
  60 // DownloadResourceHandler members from the UI thread.
  61 static void StartOnUIThread(
  62     scoped_ptr<DownloadCreateInfo> info,
  63     scoped_ptr<DownloadResourceHandler::DownloadTabInfo> tab_info,
  64     scoped_ptr<ByteStreamReader> stream,
  65     const DownloadUrlParameters::OnStartedCallback& started_cb) {
  66   DCHECK_CURRENTLY_ON(BrowserThread::UI);
  67
  68   DownloadManager* download_manager = info->request_handle.GetDownloadManager();
  69   if (!download_manager) {
  70     // NULL in unittests or if the page closed right after starting the
  71     // download.
  72     if (!started_cb.is_null())
  73       started_cb.Run(NULL, DOWNLOAD_INTERRUPT_REASON_USER_CANCELED);
  74
  75     // |stream| gets deleted on non-FILE thread, but it's ok since
  76     // we're not using stream_writer_ yet.
  77
  78     return;
  79   }
  80
  81   info->tab_url = tab_info->tab_url;
  82   info->tab_referrer_url = tab_info->tab_referrer_url;
  83
  84   download_manager->StartDownload(info.Pass(), stream.Pass(), started_cb);
  85 }
  86
  87 void InitializeDownloadTabInfoOnUIThread(
  88     const DownloadRequestHandle& request_handle,
  89     DownloadResourceHandler::DownloadTabInfo* tab_info) {
  90   DCHECK_CURRENTLY_ON(BrowserThread::UI);
  91
  92   WebContents* web_contents = request_handle.GetWebContents();
  93   if (web_contents) {
  94     NavigationEntry* entry = web_contents->GetController().GetVisibleEntry();
  95     if (entry) {
  96       tab_info->tab_url = entry->GetURL();
  97       tab_info->tab_referrer_url = entry->GetReferrer().url;
  98     }
  99   }
 100 }
 101
 102 void DeleteOnUIThread(
 103     scoped_ptr<DownloadResourceHandler::DownloadTabInfo> tab_info) {}
 104
 105 }  // namespace
 106
 107 const int DownloadResourceHandler::kDownloadByteStreamSize = 100 * 1024;
 108
 109 DownloadResourceHandler::DownloadResourceHandler(
 110     uint32 id,
 111     net::URLRequest* request,
 112     const DownloadUrlParameters::OnStartedCallback& started_cb,
 113     scoped_ptr<DownloadSaveInfo> save_info)
 114     : ResourceHandler(request),
 115       download_id_(id),
 116       started_cb_(started_cb),
 117       save_info_(save_info.Pass()),
 118       tab_info_(new DownloadTabInfo()),
 119       last_buffer_size_(0),
 120       bytes_read_(0),
 121       pause_count_(0),
 122       was_deferred_(false),
 123       on_response_started_called_(false) {
 124   RecordDownloadCount(UNTHROTTLED_COUNT);
 125
 126   // Do UI thread initialization for tab_info_ asap after
 127   // DownloadResourceHandler creation since the tab could be navigated
 128   // before StartOnUIThread gets called.  This is safe because deletion
 129   // will occur via PostTask() as well, which will serialized behind this
 130   // PostTask()
 131   const ResourceRequestInfoImpl* request_info = GetRequestInfo();
 132   BrowserThread::PostTask(
 133       BrowserThread::UI, FROM_HERE,
 134       base::Bind(&InitializeDownloadTabInfoOnUIThread,
 135                  DownloadRequestHandle(AsWeakPtr(), request_info->GetChildID(),
 136                                        request_info->GetRouteID(),
 137                                        request_info->GetRequestID(),
 138                                        request_info->frame_tree_node_id()),
 139                  tab_info_.get()));
 140   power_save_blocker_ = PowerSaveBlocker::Create(
 141       PowerSaveBlocker::kPowerSaveBlockPreventAppSuspension,
 142       PowerSaveBlocker::kReasonOther, "Download in progress");
 143 }
 144
 145 bool DownloadResourceHandler::OnUploadProgress(uint64 position,
 146                                                uint64 size) {
 147   return true;
 148 }
 149
 150 bool DownloadResourceHandler::OnRequestRedirected(
 151     const net::RedirectInfo& redirect_info,
 152     ResourceResponse* response,
 153     bool* defer) {
 154   return true;
 155 }
 156
 157 // Send the download creation information to the download thread.
 158 bool DownloadResourceHandler::OnResponseStarted(
 159     ResourceResponse* response,
 160     bool* defer) {
 161   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 162   // There can be only one (call)
 163   DCHECK(!on_response_started_called_);
 164   on_response_started_called_ = true;
 165
 166   DVLOG(20) << __FUNCTION__ << "()" << DebugString();
 167   download_start_time_ = base::TimeTicks::Now();
 168
 169   // If it's a download, we don't want to poison the cache with it.
 170   request()->StopCaching();
 171
 172   // Lower priority as well, so downloads don't contend for resources
 173   // with main frames.
 174   request()->SetPriority(net::IDLE);
 175
 176   // If the content-length header is not present (or contains something other
 177   // than numbers), the incoming content_length is -1 (unknown size).
 178   // Set the content length to 0 to indicate unknown size to DownloadManager.
 179   int64 content_length =
 180       response->head.content_length > 0 ? response->head.content_length : 0;
 181
 182   const ResourceRequestInfoImpl* request_info = GetRequestInfo();
 183
 184   // Deleted in DownloadManager.
 185   scoped_ptr<DownloadCreateInfo> info(
 186       new DownloadCreateInfo(base::Time::Now(),
 187                              content_length,
 188                              request()->net_log(),
 189                              request_info->HasUserGesture(),
 190                              request_info->GetPageTransition(),
 191                              save_info_.Pass()));
 192
 193   // Create the ByteStream for sending data to the download sink.
 194   scoped_ptr<ByteStreamReader> stream_reader;
 195   CreateByteStream(
 196       base::ThreadTaskRunnerHandle::Get(),
 197       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE),
 198       kDownloadByteStreamSize, &stream_writer_, &stream_reader);
 199   stream_writer_->RegisterCallback(
 200       base::Bind(&DownloadResourceHandler::ResumeRequest, AsWeakPtr()));
 201
 202   info->download_id = download_id_;
 203   info->url_chain = request()->url_chain();
 204   info->referrer_url = GURL(request()->referrer());
 205   info->mime_type = response->head.mime_type;
 206   info->remote_address = request()->GetSocketAddress().host();
 207   request()->GetResponseHeaderByName("content-disposition",
 208                                      &info->content_disposition);
 209   RecordDownloadMimeType(info->mime_type);
 210   RecordDownloadContentDisposition(info->content_disposition);
 211
 212   info->request_handle = DownloadRequestHandle(
 213       AsWeakPtr(), request_info->GetChildID(), request_info->GetRouteID(),
 214       request_info->GetRequestID(), request_info->frame_tree_node_id());
 215
 216   // Get the last modified time and etag.
 217   const net::HttpResponseHeaders* headers = request()->response_headers();
 218   if (headers) {
 219     if (headers->HasStrongValidators()) {
 220       // If we don't have strong validators as per RFC 2616 section 13.3.3, then
 221       // we neither store nor use them for range requests.
 222       if (!headers->EnumerateHeader(NULL, "Last-Modified",
 223                                     &info->last_modified))
 224         info->last_modified.clear();
 225       if (!headers->EnumerateHeader(NULL, "ETag", &info->etag))
 226         info->etag.clear();
 227     }
 228
 229     int status = headers->response_code();
 230     if (2 == status / 100  && status != net::HTTP_PARTIAL_CONTENT) {
 231       // Success & not range response; if we asked for a range, we didn't
 232       // get it--reset the file pointers to reflect that.
 233       info->save_info->offset = 0;
 234       info->save_info->hash_state = "";
 235     }
 236
 237     if (!headers->GetMimeType(&info->original_mime_type))
 238       info->original_mime_type.clear();
 239   }
 240
 241   // Blink verifies that the requester of this download is allowed to set a
 242   // suggested name for the security origin of the downlaod URL. However, this
 243   // assumption doesn't hold if there were cross origin redirects. Therefore,
 244   // clear the suggested_name for such requests.
 245   if (info->url_chain.size() > 1 &&
 246       info->url_chain.front().GetOrigin() != info->url_chain.back().GetOrigin())
 247     info->save_info->suggested_name.clear();
 248
 249   BrowserThread::PostTask(
 250       BrowserThread::UI, FROM_HERE,
 251       base::Bind(&StartOnUIThread,
 252                  base::Passed(&info),
 253                  base::Passed(&tab_info_),
 254                  base::Passed(&stream_reader),
 255                  // Pass to StartOnUIThread so that variable
 256                  // access is always on IO thread but function
 257                  // is called on UI thread.
 258                  started_cb_));
 259   // Guaranteed to be called in StartOnUIThread
 260   started_cb_.Reset();
 261
 262   return true;
 263 }
 264
 265 void DownloadResourceHandler::CallStartedCB(
 266     DownloadItem* item,
 267     DownloadInterruptReason interrupt_reason) {
 268   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 269   if (started_cb_.is_null())
 270     return;
 271   BrowserThread::PostTask(
 272       BrowserThread::UI,
 273       FROM_HERE,
 274       base::Bind(
 275           &CallStartedCBOnUIThread, started_cb_, item, interrupt_reason));
 276   started_cb_.Reset();
 277 }
 278
 279 bool DownloadResourceHandler::OnWillStart(const GURL& url, bool* defer) {
 280   return true;
 281 }
 282
 283 bool DownloadResourceHandler::OnBeforeNetworkStart(const GURL& url,
 284                                                    bool* defer) {
 285   return true;
 286 }
 287
 288 // Create a new buffer, which will be handed to the download thread for file
 289 // writing and deletion.
 290 bool DownloadResourceHandler::OnWillRead(scoped_refptr<net::IOBuffer>* buf,
 291                                          int* buf_size,
 292                                          int min_size) {
 293   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 294   DCHECK(buf && buf_size);
 295   DCHECK(!read_buffer_.get());
 296
 297   *buf_size = min_size < 0 ? kReadBufSize : min_size;
 298   last_buffer_size_ = *buf_size;
 299   read_buffer_ = new net::IOBuffer(*buf_size);
 300   *buf = read_buffer_.get();
 301   return true;
 302 }
 303
 304 // Pass the buffer to the download file writer.
 305 bool DownloadResourceHandler::OnReadCompleted(int bytes_read, bool* defer) {
 306   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 307   DCHECK(read_buffer_.get());
 308
 309   base::TimeTicks now(base::TimeTicks::Now());
 310   if (!last_read_time_.is_null()) {
 311     double seconds_since_last_read = (now - last_read_time_).InSecondsF();
 312     if (now == last_read_time_)
 313       // Use 1/10 ms as a "very small number" so that we avoid
 314       // divide-by-zero error and still record a very high potential bandwidth.
 315       seconds_since_last_read = 0.00001;
 316
 317     double actual_bandwidth = (bytes_read)/seconds_since_last_read;
 318     double potential_bandwidth = last_buffer_size_/seconds_since_last_read;
 319     RecordBandwidth(actual_bandwidth, potential_bandwidth);
 320   }
 321   last_read_time_ = now;
 322
 323   if (!bytes_read)
 324     return true;
 325   bytes_read_ += bytes_read;
 326   DCHECK(read_buffer_.get());
 327
 328   // Take the data ship it down the stream.  If the stream is full, pause the
 329   // request; the stream callback will resume it.
 330   if (!stream_writer_->Write(read_buffer_, bytes_read)) {
 331     PauseRequest();
 332     *defer = was_deferred_ = true;
 333     last_stream_pause_time_ = now;
 334   }
 335
 336   read_buffer_ = NULL;  // Drop our reference.
 337
 338   if (pause_count_ > 0)
 339     *defer = was_deferred_ = true;
 340
 341   return true;
 342 }
 343
 344 void DownloadResourceHandler::OnResponseCompleted(
 345     const net::URLRequestStatus& status,
 346     const std::string& security_info,
 347     bool* defer) {
 348   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 349   int response_code = status.is_success() ? request()->GetResponseCode() : 0;
 350   DVLOG(20) << __FUNCTION__ << "()" << DebugString()
 351             << " status.status() = " << status.status()
 352             << " status.error() = " << status.error()
 353             << " response_code = " << response_code;
 354
 355   net::Error error_code = net::OK;
 356   if (status.status() == net::URLRequestStatus::FAILED ||
 357       // Note cancels as failures too.
 358       status.status() == net::URLRequestStatus::CANCELED) {
 359     error_code = static_cast<net::Error>(status.error());  // Normal case.
 360     // Make sure that at least the fact of failure comes through.
 361     if (error_code == net::OK)
 362       error_code = net::ERR_FAILED;
 363   }
 364
 365   // ERR_CONTENT_LENGTH_MISMATCH and ERR_INCOMPLETE_CHUNKED_ENCODING are
 366   // allowed since a number of servers in the wild close the connection too
 367   // early by mistake. Other browsers - IE9, Firefox 11.0, and Safari 5.1.4 -
 368   // treat downloads as complete in both cases, so we follow their lead.
 369   if (error_code == net::ERR_CONTENT_LENGTH_MISMATCH ||
 370       error_code == net::ERR_INCOMPLETE_CHUNKED_ENCODING) {
 371     error_code = net::OK;
 372   }
 373   DownloadInterruptReason reason =
 374       ConvertNetErrorToInterruptReason(
 375         error_code, DOWNLOAD_INTERRUPT_FROM_NETWORK);
 376
 377   if (status.status() == net::URLRequestStatus::CANCELED &&
 378       status.error() == net::ERR_ABORTED) {
 379     // CANCELED + ERR_ABORTED == something outside of the network
 380     // stack cancelled the request.  There aren't that many things that
 381     // could do this to a download request (whose lifetime is separated from
 382     // the tab from which it came).  We map this to USER_CANCELLED as the
 383     // case we know about (system suspend because of laptop close) corresponds
 384     // to a user action.
 385     // TODO(ahendrickson) -- Find a better set of codes to use here, as
 386     // CANCELED/ERR_ABORTED can occur for reasons other than user cancel.
 387     if (net::IsCertStatusError(request()->ssl_info().cert_status))
 388       reason = DOWNLOAD_INTERRUPT_REASON_SERVER_CERT_PROBLEM;
 389     else
 390       reason = DOWNLOAD_INTERRUPT_REASON_USER_CANCELED;
 391   }
 392
 393   if (status.is_success() &&
 394       reason == DOWNLOAD_INTERRUPT_REASON_NONE &&
 395       request()->response_headers()) {
 396     // Handle server's response codes.
 397     switch(response_code) {
 398       case -1:                          // Non-HTTP request.
 399       case net::HTTP_OK:
 400       case net::HTTP_CREATED:
 401       case net::HTTP_ACCEPTED:
 402       case net::HTTP_NON_AUTHORITATIVE_INFORMATION:
 403       case net::HTTP_RESET_CONTENT:
 404       case net::HTTP_PARTIAL_CONTENT:
 405         // Expected successful codes.
 406         break;
 407       case net::HTTP_NO_CONTENT:
 408       case net::HTTP_NOT_FOUND:
 409         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_BAD_CONTENT;
 410         break;
 411       case net::HTTP_PRECONDITION_FAILED:
 412         // Failed our 'If-Unmodified-Since' or 'If-Match'; see
 413         // download_manager_impl.cc BeginDownload()
 414         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_PRECONDITION;
 415         break;
 416       case net::HTTP_REQUESTED_RANGE_NOT_SATISFIABLE:
 417         // Retry by downloading from the start automatically:
 418         // If we haven't received data when we get this error, we won't.
 419         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_NO_RANGE;
 420         break;
 421       case net::HTTP_UNAUTHORIZED:
 422         // Server didn't authorize this request.
 423         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_UNAUTHORIZED;
 424         break;
 425       case net::HTTP_FORBIDDEN:
 426         // Server forbids access to this resource.
 427         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_FORBIDDEN;
 428         break;
 429       default:    // All other errors.
 430         // Redirection and informational codes should have been handled earlier
 431         // in the stack.
 432         DCHECK_NE(3, response_code / 100);
 433         DCHECK_NE(1, response_code / 100);
 434         reason = DOWNLOAD_INTERRUPT_REASON_SERVER_FAILED;
 435         break;
 436     }
 437   }
 438
 439   std::string accept_ranges;
 440   bool has_strong_validators = false;
 441   if (request()->response_headers()) {
 442     request()->response_headers()->EnumerateHeader(
 443         NULL, "Accept-Ranges", &accept_ranges);
 444     has_strong_validators =
 445         request()->response_headers()->HasStrongValidators();
 446   }
 447   RecordAcceptsRanges(accept_ranges, bytes_read_, has_strong_validators);
 448   RecordNetworkBlockage(base::TimeTicks::Now() - download_start_time_,
 449                         total_pause_time_);
 450
 451   CallStartedCB(NULL, reason);
 452
 453   // Send the info down the stream.  Conditional is in case we get
 454   // OnResponseCompleted without OnResponseStarted.
 455   if (stream_writer_)
 456     stream_writer_->Close(reason);
 457
 458   // If the error mapped to something unknown, record it so that
 459   // we can drill down.
 460   if (reason == DOWNLOAD_INTERRUPT_REASON_NETWORK_FAILED) {
 461     UMA_HISTOGRAM_SPARSE_SLOWLY("Download.MapErrorNetworkFailed",
 462                                 std::abs(status.error()));
 463   }
 464
 465   stream_writer_.reset();  // We no longer need the stream.
 466   read_buffer_ = NULL;
 467 }
 468
 469 void DownloadResourceHandler::OnDataDownloaded(int bytes_downloaded) {
 470   NOTREACHED();
 471 }
 472
 473 void DownloadResourceHandler::PauseRequest() {
 474   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 475
 476   ++pause_count_;
 477 }
 478
 479 void DownloadResourceHandler::ResumeRequest() {
 480   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 481   DCHECK_LT(0, pause_count_);
 482
 483   --pause_count_;
 484
 485   if (!was_deferred_)
 486     return;
 487   if (pause_count_ > 0)
 488     return;
 489
 490   was_deferred_ = false;
 491   if (!last_stream_pause_time_.is_null()) {
 492     total_pause_time_ += (base::TimeTicks::Now() - last_stream_pause_time_);
 493     last_stream_pause_time_ = base::TimeTicks();
 494   }
 495
 496   controller()->Resume();
 497 }
 498
 499 void DownloadResourceHandler::CancelRequest() {
 500   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 501
 502   const ResourceRequestInfo* info = GetRequestInfo();
 503   ResourceDispatcherHostImpl::Get()->CancelRequest(
 504       info->GetChildID(),
 505       info->GetRequestID());
 506   // This object has been deleted.
 507 }
 508
 509 std::string DownloadResourceHandler::DebugString() const {
 510   const ResourceRequestInfo* info = GetRequestInfo();
 511   return base::StringPrintf("{"
 512                             " url_ = " "\"%s\""
 513                             " info = {"
 514                             " child_id = " "%d"
 515                             " request_id = " "%d"
 516                             " route_id = " "%d"
 517                             " }"
 518                             " }",
 519                             request() ?
 520                                 request()->url().spec().c_str() :
 521                                 "<NULL request>",
 522                             info->GetChildID(),
 523                             info->GetRequestID(),
 524                             info->GetRouteID());
 525 }
 526
 527 DownloadResourceHandler::~DownloadResourceHandler() {
 528   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 529
 530   // This won't do anything if the callback was called before.
 531   // If it goes through, it will likely be because OnWillStart() returned
 532   // false somewhere in the chain of resource handlers.
 533   CallStartedCB(NULL, DOWNLOAD_INTERRUPT_REASON_NETWORK_FAILED);
 534
 535   // Remove output stream callback if a stream exists.
 536   if (stream_writer_)
 537     stream_writer_->RegisterCallback(base::Closure());
 538
 539   // tab_info_ must be destroyed on UI thread, since
 540   // InitializeDownloadTabInfoOnUIThread might still be using it.
 541   if (tab_info_.get()) {
 542     BrowserThread::PostTask(
 543         BrowserThread::UI, FROM_HERE,
 544         base::Bind(&DeleteOnUIThread, base::Passed(&tab_info_)));
 545   }
 546
 547   UMA_HISTOGRAM_TIMES("SB2.DownloadDuration",
 548                       base::TimeTicks::Now() - download_start_time_);
 549 }
 550
 551 }  // namespace content