| // Copyright (c) 2012 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 "base/rand_util.h" | 
 |  | 
 | #include <stdlib.h> | 
 |  | 
 | #include "base/basictypes.h" | 
 | #include "base/logging.h" | 
 |  | 
 | namespace { | 
 |  | 
 | uint32 RandUint32() { | 
 |   uint32 number; | 
 |   CHECK_EQ(rand_s(&number), 0); | 
 |   return number; | 
 | } | 
 |  | 
 | }  // namespace | 
 |  | 
 | namespace base { | 
 |  | 
 | // NOTE: This function must be cryptographically secure. http://crbug.com/140076 | 
 | uint64 RandUint64() { | 
 |   uint32 first_half = RandUint32(); | 
 |   uint32 second_half = RandUint32(); | 
 |   return (static_cast<uint64>(first_half) << 32) + second_half; | 
 | } | 
 |  | 
 | }  // namespace base |