/* * cc_cmp_safe.c * corecrypto * * Created on 04/22/2014 * * Copyright (c) 2014,2015 Apple Inc. All rights reserved. * * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ #include <corecrypto/cc_priv.h> int cc_cmp_safe (size_t num, const void * ptr1, const void * ptr2) { size_t i; const uint8_t *s=(const uint8_t *)ptr1; const uint8_t *t=(const uint8_t *)ptr2; uint8_t flag=((num<=0)?1:0); // If 0 return an error for (i=0;i<num;i++) { flag|=(s[i]^t[i]); } HEAVISIDE_STEP_UINT8(flag,flag); // flag=(flag==0)?0:1; return flag; // 0 iff all bytes were equal, 1 if there is any difference }