|  | // Copyright 2015 The Weave 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 LIBUWEAVE_SRC_CRYPTO_UTILS_H_ | 
|  | #define LIBUWEAVE_SRC_CRYPTO_UTILS_H_ | 
|  |  | 
|  | #include <stdbool.h> | 
|  | #include <stddef.h> | 
|  | #include <stdint.h> | 
|  |  | 
|  | /** | 
|  | * Check if two byte arrays are the same in constant time (the running time | 
|  | * should only depend on the length of the given arrays). It's critical to use | 
|  | * constant-time methods to compare secret data. Timing information can lead to | 
|  | * full recovery of the secret data. | 
|  | */ | 
|  | bool uw_crypto_utils_equal_(const uint8_t* arr1, | 
|  | const uint8_t* arr2, | 
|  | size_t len); | 
|  |  | 
|  | #endif  // LIBUWEAVE_SRC_CRYPTO_UTILS_H_ |