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#ifndef CONTENT_BROWSER_LOADER_CROSS_SITE_RESOURCE_HANDLER_H_
6#define CONTENT_BROWSER_LOADER_CROSS_SITE_RESOURCE_HANDLER_H_
7
8#include "base/memory/ref_counted.h"
9#include "base/memory/weak_ptr.h"
10#include "content/browser/loader/layered_resource_handler.h"
11#include "content/common/content_export.h"
12#include "net/url_request/url_request_status.h"
13
14namespace net {
15class URLRequest;
16}
17
18namespace content {
19
20struct TransitionLayerData;
21
22// Ensures that responses are delayed for navigations that must be transferred
23// to a different process.  This handler wraps an AsyncEventHandler, and it sits
24// inside SafeBrowsing and Buffered event handlers.  This is important, so that
25// it can intercept OnResponseStarted after we determine that a response is safe
26// and not a download.
27class CrossSiteResourceHandler : public LayeredResourceHandler {
28 public:
29  CrossSiteResourceHandler(scoped_ptr<ResourceHandler> next_handler,
30                           net::URLRequest* request);
31  virtual ~CrossSiteResourceHandler();
32
33  // ResourceHandler implementation:
34  virtual bool OnRequestRedirected(const net::RedirectInfo& redirect_info,
35                                   ResourceResponse* response,
36                                   bool* defer) OVERRIDE;
37  virtual bool OnResponseStarted(ResourceResponse* response,
38                                 bool* defer) OVERRIDE;
39  virtual bool OnReadCompleted(int bytes_read,
40                               bool* defer) OVERRIDE;
41  virtual void OnResponseCompleted(const net::URLRequestStatus& status,
42                                   const std::string& security_info,
43                                   bool* defer) OVERRIDE;
44
45  // We can now send the response to the new renderer, which will cause
46  // WebContentsImpl to swap in the new renderer and destroy the old one.
47  void ResumeResponse();
48
49  // When set to true, requests are leaked when they can't be passed to a
50  // RenderViewHost, for unit tests.
51  CONTENT_EXPORT static void SetLeakRequestsForTesting(
52      bool leak_requests_for_testing);
53
54  // Navigations are deferred at OnResponseStarted to parse out any navigation
55  // transition link headers, and give the navigation transition (if it exists)
56  // a chance to run.
57  void ResumeResponseDeferredAtStart(int request_id);
58
59  // Returns whether the handler is deferred.
60  bool did_defer_for_testing() const { return did_defer_; }
61
62 private:
63  // Prepare to transfer the cross-site response to a new RenderFrameHost, by
64  // asking it to issue an identical request (on the UI thread).
65  void StartCrossSiteTransition(ResourceResponse* response);
66
67  // Defer the navigation to the UI thread to check whether transfer is required
68  // or not. Currently only used in --site-per-process.
69  bool DeferForNavigationPolicyCheck(ResourceRequestInfoImpl* info,
70                                     ResourceResponse* response,
71                                     bool* defer);
72
73  bool OnNavigationTransitionResponseStarted(
74      ResourceResponse* response,
75      bool* defer,
76      const TransitionLayerData& transition_data);
77
78  bool OnNormalResponseStarted(ResourceResponse* response,
79                               bool* defer);
80
81  void ResumeOrTransfer(bool is_transfer);
82  void ResumeIfDeferred();
83
84  // Called when about to defer a request.  Sets |did_defer_| and logs the
85  // defferral
86  void OnDidDefer();
87
88  bool has_started_response_;
89  bool in_cross_site_transition_;
90  bool completed_during_transition_;
91  bool did_defer_;
92  net::URLRequestStatus completed_status_;
93  std::string completed_security_info_;
94  scoped_refptr<ResourceResponse> response_;
95
96  // TODO(nasko): WeakPtr is needed in --site-per-process, since all navigations
97  // are deferred to the UI thread and come back to IO thread via
98  // PostTaskAndReplyWithResult. If a transfer is needed, it goes back to the UI
99  // thread. This can be removed once the code is changed to only do one hop.
100  base::WeakPtrFactory<CrossSiteResourceHandler> weak_ptr_factory_;
101
102  DISALLOW_COPY_AND_ASSIGN(CrossSiteResourceHandler);
103};
104
105}  // namespace content
106
107#endif  // CONTENT_BROWSER_LOADER_CROSS_SITE_RESOURCE_HANDLER_H_
108