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