Stop on redirects while checking for www mismatches

chrome/browser/ssl/common_name_mismatch_handler.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 "chrome/browser/ssl/common_name_mismatch_handler.h"
 
 #include "base/callback_helpers.h"
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 #include "components/ssl_errors/error_classification.h"
@@ skipping 60 matching lines @@
   url_fetcher_ = net::URLFetcher::Create(url, net::URLFetcher::HEAD, this,
                                          traffic_annotation);
   url_fetcher_->SetAutomaticallyRetryOn5xx(false);
   url_fetcher_->SetRequestContext(request_context_.get());
 
   // Can't safely use net::LOAD_DISABLE_CERT_REVOCATION_CHECKING here,
   // since then the connection may be reused without checking the cert.
   url_fetcher_->SetLoadFlags(net::LOAD_DO_NOT_SAVE_COOKIES |
                              net::LOAD_DO_NOT_SEND_COOKIES |
                              net::LOAD_DO_NOT_SEND_AUTH_DATA);
+  // Don't follow redirects to prevent leaking URL data to HTTP sites.
+  url_fetcher_->SetStopOnRedirect(true);
   url_fetcher_->Start();
 }
 
 // static
 bool CommonNameMismatchHandler::GetSuggestedUrl(
     const GURL& request_url,
     const std::vector<std::string>& dns_names,
     GURL* suggested_url) {
   std::string www_mismatch_hostname;
   if (!ssl_errors::GetWWWSubDomainMatch(request_url, dns_names,
@@ skipping 19 matching lines @@
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
   DCHECK(IsCheckingSuggestedUrl());
   DCHECK_EQ(url_fetcher_.get(), source);
   DCHECK(!check_url_callback_.is_null());
   DCHECK(!url_fetcher_.get()->GetStatus().is_io_pending());
 
   SuggestedUrlCheckResult result = SUGGESTED_URL_NOT_AVAILABLE;
   // Save a copy of |suggested_url| so it can be used after |url_fetcher_|
   // is destroyed.
   const GURL suggested_url = url_fetcher_->GetOriginalURL();
-  const GURL& landing_url = url_fetcher_->GetURL();
+  const GURL landing_url = url_fetcher_->GetURL();
 
   // Make sure the |landing_url| is a HTTPS page and returns a proper response
   // code.
   if (url_fetcher_.get()->GetResponseCode() == 200 &&
       landing_url.SchemeIsCryptographic() &&
       landing_url.host() != request_url_.host()) {
+    DCHECK_EQ(landing_url.host(), suggested_url.host());
     result = SUGGESTED_URL_AVAILABLE;
   }
   url_fetcher_.reset();
   base::ResetAndReturn(&check_url_callback_).Run(result, suggested_url);
 }
 
 bool CommonNameMismatchHandler::IsCheckingSuggestedUrl() const {
   return !!url_fetcher_;
 }