[Downloads] Do not store error responses during resumption.

content/browser/download/url_downloader.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/download/url_downloader.h"
 
 #include "base/callback_helpers.h"
 #include "base/location.h"
 #include "base/macros.h"
 #include "base/threading/sequenced_task_runner_handle.h"
@@ skipping 128 matching lines @@
     return;
 
   request_->set_delegate(this);
   request_->Start();
 }
 
 void UrlDownloader::OnReceivedRedirect(net::URLRequest* request,
                                        const net::RedirectInfo& redirect_info,
                                        bool* defer_redirect) {
   DVLOG(1) << "OnReceivedRedirect: " << request_->url().spec();
+  handler_.OnRequestRedirected(redirect_info);
+
+  // We are going to block redirects even if DownloadRequestCore allows it.  No
+  // redirects are expected for download requests that are made without a
+  // renderer, which are currently exclusively resumption requests. Since there
+  // is no security policy being applied here, it's safer to block redirects and
+  // revisit if some previously unknown legitimate use case arises for redirects
+  // while resuming.
+  CallStartedCallbackOnFailure(DOWNLOAD_INTERRUPT_REASON_SERVER_UNREACHABLE);
   request_->CancelWithError(net::ERR_ABORTED);

[svaldez, 2016/01/13 17:29:18]

Might actually want to change this to a more appropriate error code.

[asanka, 2016/01/28 02:24:17]

Changed to ERR_UNSAFE_REDIRECT which is the error code used by URLRequest to
indicate a redirect that was deemed unsafe by the URLRequestJob.

 }
 
 void UrlDownloader::OnResponseStarted(net::URLRequest* request) {
   DVLOG(1) << "OnResponseStarted: " << request_->url().spec();
 
   if (!request_->status().is_success()) {
     ResponseCompleted();
     return;
   }
 
   scoped_ptr<DownloadCreateInfo> create_info;
   scoped_ptr<ByteStreamReader> stream_reader;
 
-  handler_.OnResponseStarted(&create_info, &stream_reader);
+  DownloadInterruptReason result =
+      handler_.OnResponseStarted(&create_info, &stream_reader);
+  if (result != DOWNLOAD_INTERRUPT_REASON_NONE) {
+    CallStartedCallbackOnFailure(result);
+    Done();
+    return;
+  }
 
   create_info->download_id = download_id_;
   create_info->request_handle.reset(
       new RequestHandle(weak_ptr_factory_.GetWeakPtr(), manager_,
                         base::SequencedTaskRunnerHandle::Get()));
   BrowserThread::PostTask(
       BrowserThread::UI, FROM_HERE,
       base::Bind(&DownloadManagerImpl::StartDownload, manager_,
                  base::Passed(&create_info), base::Passed(&stream_reader),
                  base::ResetAndReturn(&on_started_callback_)));
@@ skipping 71 matching lines @@
     // URLRequest reported an EOF. Call ResponseCompleted.
     DCHECK_EQ(0, bytes_read);
     ResponseCompleted();
   }
 }
 
 void UrlDownloader::ResponseCompleted() {
   DVLOG(1) << "ResponseCompleted: " << request_->url().spec();
 
   handler_.OnResponseCompleted(request_->status());
-  BrowserThread::PostTask(
-      BrowserThread::UI, FROM_HERE,
-      base::Bind(&DownloadManagerImpl::RemoveUrlDownloader, manager_, this));
+  Done();
 }
 
 void UrlDownloader::ResumeReading() {
   if (request_->status().is_success()) {
     StartReading(false);  // Read the next chunk (OK to complete synchronously).
   } else {
     ResponseCompleted();
   }
 }
 
 void UrlDownloader::CallStartedCallbackOnFailure(
     DownloadInterruptReason result) {
   if (on_started_callback_.is_null())
     return;
   BrowserThread::PostTask(
       BrowserThread::UI, FROM_HERE,
       base::Bind(base::ResetAndReturn(&on_started_callback_), nullptr, result));
 }
 
 void UrlDownloader::PauseRequest() {
   handler_.PauseRequest();
 }
 
 void UrlDownloader::ResumeRequest() {
   handler_.ResumeRequest();
 }
 
 void UrlDownloader::CancelRequest() {
+  Done();
+}
+
+void UrlDownloader::Done() {
   BrowserThread::PostTask(
       BrowserThread::UI, FROM_HERE,
       base::Bind(&DownloadManagerImpl::RemoveUrlDownloader, manager_, this));
 }
 
 }  // namespace content