Push API: Validate storage before returning cached subscriptions

chrome/browser/push_messaging/push_messaging_app_identifier.cc

 // Copyright 2014 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/push_messaging/push_messaging_app_identifier.h"
 
 #include <string.h>
 
 #include "base/guid.h"
 #include "base/logging.h"
@@ skipping 56 matching lines @@
 // static
 bool PushMessagingAppIdentifier::UseInstanceID(const std::string& app_id) {
   return base::EndsWith(app_id, kInstanceIDGuidSuffix,
                         base::CompareCase::SENSITIVE);
 }
 
 // static
 PushMessagingAppIdentifier PushMessagingAppIdentifier::Generate(
     const GURL& origin,
     int64_t service_worker_registration_id) {
+  // All new push subscriptions use Instance ID tokens.
+  return GenerateInternal(origin, service_worker_registration_id,
+                          true /* use_instance_id */);
+}
+
+// static
+PushMessagingAppIdentifier PushMessagingAppIdentifier::LegacyGenerateForTesting(
+    const GURL& origin,
+    int64_t service_worker_registration_id) {
+  return GenerateInternal(origin, service_worker_registration_id,
+                          false /* use_instance_id */);
+}
+
+// static
+PushMessagingAppIdentifier PushMessagingAppIdentifier::GenerateInternal(
+    const GURL& origin,
+    int64_t service_worker_registration_id,
+    bool use_instance_id) {
   // Use uppercase GUID for consistency with GUIDs Push has already sent to GCM.
   // Also allows detecting case mangling; see code commented "crbug.com/461867".
   std::string guid = base::ToUpperASCII(base::GenerateGUID());
-  // All new push subscriptions are Instance ID tokens.
-  guid.replace(guid.size() - kGuidSuffixLength, kGuidSuffixLength,
-               kInstanceIDGuidSuffix);
+  if (use_instance_id) {
+    guid.replace(guid.size() - kGuidSuffixLength, kGuidSuffixLength,
+                 kInstanceIDGuidSuffix);
+  }
   CHECK(!guid.empty());
   std::string app_id =
       kPushMessagingAppIdentifierPrefix + origin.spec() + kSeparator + guid;
 
   PushMessagingAppIdentifier app_identifier(app_id, origin,
                                             service_worker_registration_id);
   app_identifier.DCheckValid();
   return app_identifier;
 }
 
@@ skipping 150 matching lines @@
   if (UseInstanceID(app_id_)) {
     DCHECK(!base::IsValidGUID(guid));
 
     // Replace suffix with valid hex so we can validate the rest of the string.
     guid = guid.replace(guid.size() - kGuidSuffixLength, kGuidSuffixLength,
                         kGuidSuffixLength, 'C');
   }
   DCHECK(base::IsValidGUID(guid));
 #endif  // DCHECK_IS_ON()
 }