safe_browsing_resource_throttle.h revision eb525c5499e34cc9c4b825d6d9e75bb07cc06ace 
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 CHROME_BROWSER_RENDERER_HOST_SAFE_BROWSING_RESOURCE_THROTTLE_H_
6#define CHROME_BROWSER_RENDERER_HOST_SAFE_BROWSING_RESOURCE_THROTTLE_H_
7
8#include <string>
9#include <vector>
10
11#include "base/memory/ref_counted.h"
12#include "base/time/time.h"
13#include "base/timer/timer.h"
14#include "chrome/browser/safe_browsing/database_manager.h"
15#include "chrome/browser/safe_browsing/ui_manager.h"
16#include "content/public/browser/resource_throttle.h"
17
18class ResourceDispatcherHost;
19
20namespace net {
21class URLRequest;
22}
23
24// SafeBrowsingResourceThrottle checks that URLs are "safe" before navigating
25// to them. To be considered "safe", a URL must not appear in the
26// malware/phishing blacklists (see SafeBrowsingService for details).
27//
28// This check is done before requesting the original URL, and additionally
29// before following any subsequent redirect.
30//
31// In the common case, the check completes synchronously (no match in the bloom
32// filter), so the request's flow is un-interrupted.
33//
34// However if the URL fails this quick check, it has the possibility of being
35// on the blacklist. Now the request is suspended (prevented from starting),
36// and a more expensive safe browsing check is begun (fetches the full hashes).
37//
38// Note that the safe browsing check takes at most kCheckUrlTimeoutMs
39// milliseconds. If it takes longer than this, then the system defaults to
40// treating the URL as safe.
41//
42// Once the safe browsing check has completed, if the URL was decided to be
43// dangerous, a warning page is thrown up and the request remains suspended.
44// If on the other hand the URL was decided to be safe, the request is
45// resumed.
46class SafeBrowsingResourceThrottle
47    : public content::ResourceThrottle,
48      public SafeBrowsingDatabaseManager::Client,
49      public base::SupportsWeakPtr<SafeBrowsingResourceThrottle> {
50 public:
51  SafeBrowsingResourceThrottle(const net::URLRequest* request,
52                               int render_process_host_id,
53                               int render_view_id,
54                               bool is_subresource,
55                               SafeBrowsingService* safe_browsing);
56
57  // content::ResourceThrottle implementation (called on IO thread):
58  virtual void WillStartRequest(bool* defer) OVERRIDE;
59  virtual void WillRedirectRequest(const GURL& new_url, bool* defer) OVERRIDE;
60
61  // SafeBrowsingDabaseManager::Client implementation (called on IO thread):
62  virtual void OnCheckBrowseUrlResult(
63      const GURL& url, SBThreatType result) OVERRIDE;
64
65 private:
66  // Describes what phase of the check a throttle is in.
67  enum State {
68    STATE_NONE,
69    STATE_CHECKING_URL,
70    STATE_DISPLAYING_BLOCKING_PAGE,
71  };
72
73  // Describes what stage of the request got paused by the check.
74  enum DeferState {
75    DEFERRED_NONE,
76    DEFERRED_START,
77    DEFERRED_REDIRECT,
78  };
79
80  virtual ~SafeBrowsingResourceThrottle();
81
82  // SafeBrowsingService::UrlCheckCallback implementation.
83  void OnBlockingPageComplete(bool proceed);
84
85  // Starts running |url| through the safe browsing check. Returns true if the
86  // URL is safe to visit. Otherwise returns false and will call
87  // OnBrowseUrlResult() when the check has completed.
88  bool CheckUrl(const GURL& url);
89
90  // Callback for when the safe browsing check (which was initiated by
91  // StartCheckingUrl()) has taken longer than kCheckUrlTimeoutMs.
92  void OnCheckUrlTimeout();
93
94  // Starts displaying the safe browsing interstitial page.
95  void StartDisplayingBlockingPage(const GURL& url, SBThreatType threat_type);
96
97  // Resumes the request, by continuing the deferred action (either starting the
98  // request, or following a redirect).
99  void ResumeRequest();
100
101  State state_;
102  DeferState defer_state_;
103
104  // The result of the most recent safe browsing check. Only valid to read this
105  // when state_ != STATE_CHECKING_URL.
106  SBThreatType threat_type_;
107
108  // The time when the outstanding safe browsing check was started.
109  base::TimeTicks url_check_start_time_;
110
111  // Timer to abort the safe browsing check if it takes too long.
112  base::OneShotTimer<SafeBrowsingResourceThrottle> timer_;
113
114  // The redirect chain for this resource
115  std::vector<GURL> redirect_urls_;
116
117  GURL url_being_checked_;
118
119  int render_process_host_id_;
120  int render_view_id_;
121  scoped_refptr<SafeBrowsingDatabaseManager> database_manager_;
122  scoped_refptr<SafeBrowsingUIManager> ui_manager_;
123  const net::URLRequest* request_;
124  bool is_subresource_;
125
126  DISALLOW_COPY_AND_ASSIGN(SafeBrowsingResourceThrottle);
127};
128
129
130#endif  // CHROME_BROWSER_RENDERER_HOST_SAFE_BROWSING_RESOURCE_THROTTLE_H_
131