Common Name Mismatch Handler For WWW Subdomain Mismatch case

chrome/browser/ssl/common_name_mismatch_handler.h

+// Copyright (c) 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.
+
+#ifndef CHROME_BROWSER_SSL_COMMON_NAME_MISMATCH_HANDLER_H_
+#define CHROME_BROWSER_SSL_COMMON_NAME_MISMATCH_HANDLER_H_
+
+#include "base/basictypes.h"
+#include "base/callback.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/threading/non_thread_safe.h"
+#include "base/time/time.h"
+#include "net/url_request/url_fetcher.h"
+#include "net/url_request/url_fetcher_delegate.h"
+#include "net/url_request/url_request_context_getter.h"
+#include "url/gurl.h"
+
+namespace net {
+class URLFetcher;
+}
+
+// This class handles errors due to common name mismatches
+// (|ERR_CERT_COMMON_NAME_INVALID|) and helps remediate them by suggesting
+// alternative URLs that may be what the user intended to load.
+class CommonNameMismatchHandler : public net::URLFetcherDelegate,
+                                  public base::NonThreadSafe {
+ public:
+  enum SuggestedUrlCheckResult {
+    // The request succeeds with good response code i.e. URL exists and its
+    // certificate is valid.
+    SUGGESTED_URL_AVAILABLE,
+    // Suggested URL is either not available or has a bad certificate.
+    SUGGESTED_URL_NOT_AVAILABLE
+  };
+
+  enum TestingState {
+    NOT_TESTING,
+    // Disables the actual request to the |suggested_url|.
+    IGNORE_REQUESTS_FOR_TESTING
+  };
+
+  typedef base::Callback<void(const SuggestedUrlCheckResult& result,
+                              const GURL& suggested_url)> CheckUrlCallback;
+
+  CommonNameMismatchHandler(
+      const GURL& request_url,
+      const scoped_refptr<net::URLRequestContextGetter>& request_context);
+  ~CommonNameMismatchHandler() override;
+
+  // Performs a network request to suggested URL. After completion, runs the
+  // |callback|.
+  void CheckSuggestedUrl(const GURL& url, const CheckUrlCallback& callback);
+
+  // Determines if, for |request_url| serving a certificate that is valid for
+  // the domain names |dns_names|, there is a name that the certificate is
+  // valid for that closely matches the original name in |request_url|. If
+  // so, returns true, and sets |*suggested_url| to a URL that is unlikely
+  // to cause an ERR_CERT_COMMON_NAME_INVALID error.
+  static bool GetSuggestedUrl(const GURL& request_url,
+                              const std::vector<std::string>& dns_names,
+                              GURL* suggested_url);
+
+  // Used in tests, to disable the request to |suggested_url|.
+  static void set_state_for_testing(TestingState testing_state) {

[davidben, 2015/08/17 18:59:18]

Since this makes you skip the callback, it might be better to do a
set_hang_requests_for_testing(bool) or something? I can't come up with a
terribly clear name. Certainly the comment should mention that the callback
won't get called since that's what happens from the consumer's perspective.

(Why not URLFetcherFactory?)

[Bhanu Dev, 2015/08/18 05:09:09]

Updated the comment. Similar method names and signatures are used in case of
captive portal, I thought that it might be good to keep them similar to keep
consistency. Also, I think that having an enum and setting its value might be
better than using just a boolean variable. Thanks.

+    testing_state_ = testing_state;
+  }
+
+  // Cancels the request to |suggested_url|
+  void Cancel();
+
+ private:
+  // net::URLFetcherDelegate:
+  void OnURLFetchComplete(const net::URLFetcher* source) override;
+
+  // Returns true if the check is currently running.
+  bool IsCheckingSuggestedUrl() const;
+
+  static TestingState testing_state_;
+  const GURL request_url_;
+  scoped_refptr<net::URLRequestContextGetter> request_context_;
+  CheckUrlCallback check_url_callback_;
+  scoped_ptr<net::URLFetcher> url_fetcher_;
+
+  DISALLOW_COPY_AND_ASSIGN(CommonNameMismatchHandler);
+};
+
+#endif  // CHROME_BROWSER_SSL_COMMON_NAME_MISMATCH_HANDLER_H_