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/common/resource_response.h"
28 #include "net/base/io_buffer.h"
29 #include "net/base/net_errors.h"
30 #include "net/http/http_response_headers.h"
31 #include "net/http/http_status_code.h"
32 #include "net/url_request/url_request_context.h"
33
34 namespace content {
35 namespace {
36
CallStartedCBOnUIThread(const DownloadUrlParameters::OnStartedCallback & started_cb,DownloadItem * item,net::Error error)37 void CallStartedCBOnUIThread(
38 const DownloadUrlParameters::OnStartedCallback& started_cb,
39 DownloadItem* item,
40 net::Error error) {
41 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
42
43 if (started_cb.is_null())
44 return;
45 started_cb.Run(item, error);
46 }
47
48 // Static function in order to prevent any accidental accesses to
49 // DownloadResourceHandler members from the UI thread.
StartOnUIThread(scoped_ptr<DownloadCreateInfo> info,scoped_ptr<ByteStreamReader> stream,const DownloadUrlParameters::OnStartedCallback & started_cb)50 static void StartOnUIThread(
51 scoped_ptr<DownloadCreateInfo> info,
52 scoped_ptr<ByteStreamReader> stream,
53 const DownloadUrlParameters::OnStartedCallback& started_cb) {
54 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
55
56 DownloadManager* download_manager = info->request_handle.GetDownloadManager();
57 if (!download_manager) {
58 // NULL in unittests or if the page closed right after starting the
59 // download.
60 if (!started_cb.is_null())
61 started_cb.Run(NULL, net::ERR_ACCESS_DENIED);
62 return;
63 }
64
65 download_manager->StartDownload(info.Pass(), stream.Pass(), started_cb);
66 }
67
68 } // namespace
69
70 const int DownloadResourceHandler::kDownloadByteStreamSize = 100 * 1024;
71
DownloadResourceHandler(uint32 id,net::URLRequest * request,const DownloadUrlParameters::OnStartedCallback & started_cb,scoped_ptr<DownloadSaveInfo> save_info)72 DownloadResourceHandler::DownloadResourceHandler(
73 uint32 id,
74 net::URLRequest* request,
75 const DownloadUrlParameters::OnStartedCallback& started_cb,
76 scoped_ptr<DownloadSaveInfo> save_info)
77 : ResourceHandler(request),
78 download_id_(id),
79 started_cb_(started_cb),
80 save_info_(save_info.Pass()),
81 last_buffer_size_(0),
82 bytes_read_(0),
83 pause_count_(0),
84 was_deferred_(false),
85 on_response_started_called_(false) {
86 RecordDownloadCount(UNTHROTTLED_COUNT);
87 }
88
OnUploadProgress(int request_id,uint64 position,uint64 size)89 bool DownloadResourceHandler::OnUploadProgress(int request_id,
90 uint64 position,
91 uint64 size) {
92 return true;
93 }
94
OnRequestRedirected(int request_id,const GURL & url,ResourceResponse * response,bool * defer)95 bool DownloadResourceHandler::OnRequestRedirected(
96 int request_id,
97 const GURL& url,
98 ResourceResponse* response,
99 bool* defer) {
100 // We treat a download as a main frame load, and thus update the policy URL
101 // on redirects.
102 request()->set_first_party_for_cookies(url);
103 return true;
104 }
105
106 // Send the download creation information to the download thread.
OnResponseStarted(int request_id,ResourceResponse * response,bool * defer)107 bool DownloadResourceHandler::OnResponseStarted(
108 int request_id,
109 ResourceResponse* response,
110 bool* defer) {
111 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
112 // There can be only one (call)
113 DCHECK(!on_response_started_called_);
114 on_response_started_called_ = true;
115
116 VLOG(20) << __FUNCTION__ << "()" << DebugString()
117 << " request_id = " << request_id;
118 download_start_time_ = base::TimeTicks::Now();
119
120 // If it's a download, we don't want to poison the cache with it.
121 request()->StopCaching();
122
123 // Lower priority as well, so downloads don't contend for resources
124 // with main frames.
125 request()->SetPriority(net::IDLE);
126
127 // If the content-length header is not present (or contains something other
128 // than numbers), the incoming content_length is -1 (unknown size).
129 // Set the content length to 0 to indicate unknown size to DownloadManager.
130 int64 content_length =
131 response->head.content_length > 0 ? response->head.content_length : 0;
132
133 const ResourceRequestInfoImpl* request_info = GetRequestInfo();
134
135 // Deleted in DownloadManager.
136 scoped_ptr<DownloadCreateInfo> info(
137 new DownloadCreateInfo(base::Time::Now(),
138 content_length,
139 request()->net_log(),
140 request_info->HasUserGesture(),
141 request_info->GetPageTransition(),
142 save_info_.Pass()));
143
144 // Create the ByteStream for sending data to the download sink.
145 scoped_ptr<ByteStreamReader> stream_reader;
146 CreateByteStream(
147 base::MessageLoopProxy::current(),
148 BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE),
149 kDownloadByteStreamSize, &stream_writer_, &stream_reader);
150 stream_writer_->RegisterCallback(
151 base::Bind(&DownloadResourceHandler::ResumeRequest, AsWeakPtr()));
152
153 info->download_id = download_id_;
154 info->url_chain = request()->url_chain();
155 info->referrer_url = GURL(request()->referrer());
156 info->mime_type = response->head.mime_type;
157 info->remote_address = request()->GetSocketAddress().host();
158 request()->GetResponseHeaderByName("content-disposition",
159 &info->content_disposition);
160 RecordDownloadMimeType(info->mime_type);
161 RecordDownloadContentDisposition(info->content_disposition);
162
163 info->request_handle =
164 DownloadRequestHandle(AsWeakPtr(), request_info->GetChildID(),
165 request_info->GetRouteID(),
166 request_info->GetRequestID());
167
168 // Get the last modified time and etag.
169 const net::HttpResponseHeaders* headers = request()->response_headers();
170 if (headers) {
171 if (headers->HasStrongValidators()) {
172 // If we don't have strong validators as per RFC 2616 section 13.3.3, then
173 // we neither store nor use them for range requests.
174 if (!headers->EnumerateHeader(NULL, "Last-Modified",
175 &info->last_modified))
176 info->last_modified.clear();
177 if (!headers->EnumerateHeader(NULL, "ETag", &info->etag))
178 info->etag.clear();
179 }
180
181 int status = headers->response_code();
182 if (2 == status / 100 && status != net::HTTP_PARTIAL_CONTENT) {
183 // Success & not range response; if we asked for a range, we didn't
184 // get it--reset the file pointers to reflect that.
185 info->save_info->offset = 0;
186 info->save_info->hash_state = "";
187 }
188
189 if (!headers->GetMimeType(&info->original_mime_type))
190 info->original_mime_type.clear();
191 }
192
193 BrowserThread::PostTask(
194 BrowserThread::UI, FROM_HERE,
195 base::Bind(&StartOnUIThread,
196 base::Passed(&info),
197 base::Passed(&stream_reader),
198 // Pass to StartOnUIThread so that variable
199 // access is always on IO thread but function
200 // is called on UI thread.
201 started_cb_));
202 // Guaranteed to be called in StartOnUIThread
203 started_cb_.Reset();
204
205 return true;
206 }
207
CallStartedCB(DownloadItem * item,net::Error error)208 void DownloadResourceHandler::CallStartedCB(
209 DownloadItem* item, net::Error error) {
210 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
211 if (started_cb_.is_null())
212 return;
213 BrowserThread::PostTask(
214 BrowserThread::UI, FROM_HERE,
215 base::Bind(&CallStartedCBOnUIThread, started_cb_, item, error));
216 started_cb_.Reset();
217 }
218
OnWillStart(int request_id,const GURL & url,bool * defer)219 bool DownloadResourceHandler::OnWillStart(int request_id,
220 const GURL& url,
221 bool* defer) {
222 return true;
223 }
224
225 // Create a new buffer, which will be handed to the download thread for file
226 // writing and deletion.
OnWillRead(int request_id,scoped_refptr<net::IOBuffer> * buf,int * buf_size,int min_size)227 bool DownloadResourceHandler::OnWillRead(int request_id,
228 scoped_refptr<net::IOBuffer>* buf,
229 int* buf_size,
230 int min_size) {
231 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
232 DCHECK(buf && buf_size);
233 DCHECK(!read_buffer_.get());
234
235 *buf_size = min_size < 0 ? kReadBufSize : min_size;
236 last_buffer_size_ = *buf_size;
237 read_buffer_ = new net::IOBuffer(*buf_size);
238 *buf = read_buffer_.get();
239 return true;
240 }
241
242 // Pass the buffer to the download file writer.
OnReadCompleted(int request_id,int bytes_read,bool * defer)243 bool DownloadResourceHandler::OnReadCompleted(int request_id, int bytes_read,
244 bool* defer) {
245 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
246 DCHECK(read_buffer_.get());
247
248 base::TimeTicks now(base::TimeTicks::Now());
249 if (!last_read_time_.is_null()) {
250 double seconds_since_last_read = (now - last_read_time_).InSecondsF();
251 if (now == last_read_time_)
252 // Use 1/10 ms as a "very small number" so that we avoid
253 // divide-by-zero error and still record a very high potential bandwidth.
254 seconds_since_last_read = 0.00001;
255
256 double actual_bandwidth = (bytes_read)/seconds_since_last_read;
257 double potential_bandwidth = last_buffer_size_/seconds_since_last_read;
258 RecordBandwidth(actual_bandwidth, potential_bandwidth);
259 }
260 last_read_time_ = now;
261
262 if (!bytes_read)
263 return true;
264 bytes_read_ += bytes_read;
265 DCHECK(read_buffer_.get());
266
267 // Take the data ship it down the stream. If the stream is full, pause the
268 // request; the stream callback will resume it.
269 if (!stream_writer_->Write(read_buffer_, bytes_read)) {
270 PauseRequest();
271 *defer = was_deferred_ = true;
272 last_stream_pause_time_ = now;
273 }
274
275 read_buffer_ = NULL; // Drop our reference.
276
277 if (pause_count_ > 0)
278 *defer = was_deferred_ = true;
279
280 return true;
281 }
282
OnResponseCompleted(int request_id,const net::URLRequestStatus & status,const std::string & security_info,bool * defer)283 void DownloadResourceHandler::OnResponseCompleted(
284 int request_id,
285 const net::URLRequestStatus& status,
286 const std::string& security_info,
287 bool* defer) {
288 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
289 int response_code = status.is_success() ? request()->GetResponseCode() : 0;
290 VLOG(20) << __FUNCTION__ << "()" << DebugString()
291 << " request_id = " << request_id
292 << " status.status() = " << status.status()
293 << " status.error() = " << status.error()
294 << " response_code = " << response_code;
295
296 net::Error error_code = net::OK;
297 if (status.status() == net::URLRequestStatus::FAILED ||
298 // Note cancels as failures too.
299 status.status() == net::URLRequestStatus::CANCELED) {
300 error_code = static_cast<net::Error>(status.error()); // Normal case.
301 // Make sure that at least the fact of failure comes through.
302 if (error_code == net::OK)
303 error_code = net::ERR_FAILED;
304 }
305
306 // ERR_CONTENT_LENGTH_MISMATCH and ERR_INCOMPLETE_CHUNKED_ENCODING are
307 // allowed since a number of servers in the wild close the connection too
308 // early by mistake. Other browsers - IE9, Firefox 11.0, and Safari 5.1.4 -
309 // treat downloads as complete in both cases, so we follow their lead.
310 if (error_code == net::ERR_CONTENT_LENGTH_MISMATCH ||
311 error_code == net::ERR_INCOMPLETE_CHUNKED_ENCODING) {
312 error_code = net::OK;
313 }
314 DownloadInterruptReason reason =
315 ConvertNetErrorToInterruptReason(
316 error_code, DOWNLOAD_INTERRUPT_FROM_NETWORK);
317
318 if (status.status() == net::URLRequestStatus::CANCELED &&
319 status.error() == net::ERR_ABORTED) {
320 // CANCELED + ERR_ABORTED == something outside of the network
321 // stack cancelled the request. There aren't that many things that
322 // could do this to a download request (whose lifetime is separated from
323 // the tab from which it came). We map this to USER_CANCELLED as the
324 // case we know about (system suspend because of laptop close) corresponds
325 // to a user action.
326 // TODO(ahendrickson) -- Find a better set of codes to use here, as
327 // CANCELED/ERR_ABORTED can occur for reasons other than user cancel.
328 reason = DOWNLOAD_INTERRUPT_REASON_USER_CANCELED;
329 }
330
331 if (status.is_success() &&
332 reason == DOWNLOAD_INTERRUPT_REASON_NONE &&
333 request()->response_headers()) {
334 // Handle server's response codes.
335 switch(response_code) {
336 case -1: // Non-HTTP request.
337 case net::HTTP_OK:
338 case net::HTTP_CREATED:
339 case net::HTTP_ACCEPTED:
340 case net::HTTP_NON_AUTHORITATIVE_INFORMATION:
341 case net::HTTP_RESET_CONTENT:
342 case net::HTTP_PARTIAL_CONTENT:
343 // Expected successful codes.
344 break;
345 case net::HTTP_NO_CONTENT:
346 case net::HTTP_NOT_FOUND:
347 reason = DOWNLOAD_INTERRUPT_REASON_SERVER_BAD_CONTENT;
348 break;
349 case net::HTTP_PRECONDITION_FAILED:
350 // Failed our 'If-Unmodified-Since' or 'If-Match'; see
351 // download_manager_impl.cc BeginDownload()
352 reason = DOWNLOAD_INTERRUPT_REASON_SERVER_PRECONDITION;
353 break;
354 case net::HTTP_REQUESTED_RANGE_NOT_SATISFIABLE:
355 // Retry by downloading from the start automatically:
356 // If we haven't received data when we get this error, we won't.
357 reason = DOWNLOAD_INTERRUPT_REASON_SERVER_NO_RANGE;
358 break;
359 default: // All other errors.
360 // Redirection and informational codes should have been handled earlier
361 // in the stack.
362 DCHECK_NE(3, response_code / 100);
363 DCHECK_NE(1, response_code / 100);
364 reason = DOWNLOAD_INTERRUPT_REASON_SERVER_FAILED;
365 break;
366 }
367 }
368
369 std::string accept_ranges;
370 bool has_strong_validators = false;
371 if (request()->response_headers()) {
372 request()->response_headers()->EnumerateHeader(
373 NULL, "Accept-Ranges", &accept_ranges);
374 has_strong_validators =
375 request()->response_headers()->HasStrongValidators();
376 }
377 RecordAcceptsRanges(accept_ranges, bytes_read_, has_strong_validators);
378 RecordNetworkBlockage(base::TimeTicks::Now() - download_start_time_,
379 total_pause_time_);
380
381 CallStartedCB(NULL, error_code);
382
383 // Send the info down the stream. Conditional is in case we get
384 // OnResponseCompleted without OnResponseStarted.
385 if (stream_writer_)
386 stream_writer_->Close(reason);
387
388 // If the error mapped to something unknown, record it so that
389 // we can drill down.
390 if (reason == DOWNLOAD_INTERRUPT_REASON_NETWORK_FAILED) {
391 UMA_HISTOGRAM_CUSTOM_ENUMERATION("Download.MapErrorNetworkFailed",
392 std::abs(status.error()),
393 net::GetAllErrorCodesForUma());
394 }
395
396 stream_writer_.reset(); // We no longer need the stream.
397 read_buffer_ = NULL;
398 }
399
OnDataDownloaded(int request_id,int bytes_downloaded)400 void DownloadResourceHandler::OnDataDownloaded(
401 int request_id,
402 int bytes_downloaded) {
403 NOTREACHED();
404 }
405
PauseRequest()406 void DownloadResourceHandler::PauseRequest() {
407 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
408
409 ++pause_count_;
410 }
411
ResumeRequest()412 void DownloadResourceHandler::ResumeRequest() {
413 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
414 DCHECK_LT(0, pause_count_);
415
416 --pause_count_;
417
418 if (!was_deferred_)
419 return;
420 if (pause_count_ > 0)
421 return;
422
423 was_deferred_ = false;
424 if (!last_stream_pause_time_.is_null()) {
425 total_pause_time_ += (base::TimeTicks::Now() - last_stream_pause_time_);
426 last_stream_pause_time_ = base::TimeTicks();
427 }
428
429 controller()->Resume();
430 }
431
CancelRequest()432 void DownloadResourceHandler::CancelRequest() {
433 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
434
435 const ResourceRequestInfo* info = GetRequestInfo();
436 ResourceDispatcherHostImpl::Get()->CancelRequest(
437 info->GetChildID(),
438 info->GetRequestID(),
439 false);
440 }
441
DebugString() const442 std::string DownloadResourceHandler::DebugString() const {
443 const ResourceRequestInfo* info = GetRequestInfo();
444 return base::StringPrintf("{"
445 " url_ = " "\"%s\""
446 " info = {"
447 " child_id = " "%d"
448 " request_id = " "%d"
449 " route_id = " "%d"
450 " }"
451 " }",
452 request() ?
453 request()->url().spec().c_str() :
454 "<NULL request>",
455 info->GetChildID(),
456 info->GetRequestID(),
457 info->GetRouteID());
458 }
459
~DownloadResourceHandler()460 DownloadResourceHandler::~DownloadResourceHandler() {
461 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
462
463 // This won't do anything if the callback was called before.
464 // If it goes through, it will likely be because OnWillStart() returned
465 // false somewhere in the chain of resource handlers.
466 CallStartedCB(NULL, net::ERR_ACCESS_DENIED);
467
468 // Remove output stream callback if a stream exists.
469 if (stream_writer_)
470 stream_writer_->RegisterCallback(base::Closure());
471
472 UMA_HISTOGRAM_TIMES("SB2.DownloadDuration",
473 base::TimeTicks::Now() - download_start_time_);
474 }
475
476 } // namespace content
477