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