web_request_permissions.cc revision 2a99a7e74a7f215066514fe81d2bfa6639d9eddd 
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 "chrome/browser/extensions/api/web_request/web_request_permissions.h"
6
7#include "base/string_util.h"
8#include "base/stringprintf.h"
9#include "chrome/browser/extensions/extension_info_map.h"
10#include "chrome/common/extensions/extension.h"
11#include "chrome/common/extensions/extension_constants.h"
12#include "chrome/common/url_constants.h"
13#include "content/public/browser/resource_request_info.h"
14#include "extensions/common/constants.h"
15#include "googleurl/src/gurl.h"
16#include "net/url_request/url_request.h"
17
18using content::ResourceRequestInfo;
19
20namespace {
21
22// Returns true if the URL is sensitive and requests to this URL must not be
23// modified/canceled by extensions, e.g. because it is targeted to the webstore
24// to check for updates, extension blacklisting, etc.
25bool IsSensitiveURL(const GURL& url) {
26  // TODO(battre) Merge this, CanExtensionAccessURL and
27  // Extension::CanExecuteScriptOnPage into one function.
28  bool sensitive_chrome_url = false;
29  const std::string host = url.host();
30  const char kGoogleCom[] = ".google.com";
31  const char kClient[] = "clients";
32  if (EndsWith(host, kGoogleCom, true)) {
33    // Check for "clients[0-9]*.google.com" hosts.
34    // This protects requests to several internal services such as sync,
35    // extension update pings, captive portal detection, fraudulent certificate
36    // reporting, autofill and others.
37    if (StartsWithASCII(host, kClient, true)) {
38      bool match = true;
39      for (std::string::const_iterator i = host.begin() + strlen(kClient),
40               end = host.end() - strlen(kGoogleCom); i != end; ++i) {
41        if (!isdigit(*i))
42          match = false;
43      }
44      sensitive_chrome_url = sensitive_chrome_url || match;
45    }
46    // This protects requests to safe browsing, link doctor, and possibly
47    // others.
48    sensitive_chrome_url = sensitive_chrome_url ||
49        EndsWith(url.host(), ".clients.google.com", true) ||
50        url.host() == "sb-ssl.google.com";
51  }
52  GURL::Replacements replacements;
53  replacements.ClearQuery();
54  replacements.ClearRef();
55  GURL url_without_query = url.ReplaceComponents(replacements);
56  return sensitive_chrome_url ||
57      extension_urls::IsWebstoreUpdateUrl(url_without_query) ||
58      extension_urls::IsBlacklistUpdateUrl(url);
59}
60
61// Returns true if the scheme is one we want to allow extensions to have access
62// to. Extensions still need specific permissions for a given URL, which is
63// covered by CanExtensionAccessURL.
64bool HasWebRequestScheme(const GURL& url) {
65  return (url.SchemeIs(chrome::kAboutScheme) ||
66          url.SchemeIs(chrome::kFileScheme) ||
67          url.SchemeIs(chrome::kFileSystemScheme) ||
68          url.SchemeIs(chrome::kFtpScheme) ||
69          url.SchemeIs(chrome::kHttpScheme) ||
70          url.SchemeIs(chrome::kHttpsScheme) ||
71          url.SchemeIs(extensions::kExtensionScheme));
72}
73
74}  // namespace
75
76// static
77bool WebRequestPermissions::HideRequest(
78    const ExtensionInfoMap* extension_info_map,
79    const net::URLRequest* request) {
80  // Hide requests from the Chrome WebStore App.
81  const ResourceRequestInfo* info = ResourceRequestInfo::ForRequest(request);
82  if (info && extension_info_map) {
83    int process_id = info->GetChildID();
84    const extensions::ProcessMap& process_map =
85        extension_info_map->process_map();
86    if (process_map.Contains(extension_misc::kWebStoreAppId, process_id))
87      return true;
88  }
89
90  const GURL& url = request->url();
91  return IsSensitiveURL(url) || !HasWebRequestScheme(url);
92}
93
94// static
95bool WebRequestPermissions::CanExtensionAccessURL(
96    const ExtensionInfoMap* extension_info_map,
97    const std::string& extension_id,
98    const GURL& url,
99    bool crosses_incognito,
100    bool enforce_host_permissions) {
101  // extension_info_map can be NULL in testing.
102  if (!extension_info_map)
103    return true;
104
105  const extensions::Extension* extension =
106      extension_info_map->extensions().GetByID(extension_id);
107  if (!extension)
108    return false;
109
110  // Check if this event crosses incognito boundaries when it shouldn't.
111  if (crosses_incognito && !extension_info_map->CanCrossIncognito(extension))
112    return false;
113
114  if (enforce_host_permissions) {
115    // about: URLs are not covered in host permissions, but are allowed anyway.
116    bool host_permissions_ok = (url.SchemeIs(chrome::kAboutScheme) ||
117                                extension->HasHostPermission(url) ||
118                                url.GetOrigin() == extension->url());
119    if (!host_permissions_ok)
120      return false;
121  }
122
123  return true;
124}
125