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