1/*
2 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10#include "des_local.h"
11
12DES_LONG DES_cbc_cksum(const unsigned char *in, DES_cblock *output,
13 long length, DES_key_schedule *schedule,
14 const_DES_cblock *ivec)
15{
16 register DES_LONG tout0, tout1, tin0, tin1;
17 register long l = length;
18 DES_LONG tin[2];
19 unsigned char *out = &(*output)[0];
20 const unsigned char *iv = &(*ivec)[0];
21
22 c2l(iv, tout0);
23 c2l(iv, tout1);
24 for (; l > 0; l -= 8) {
25 if (l >= 8) {
26 c2l(in, tin0);
27 c2l(in, tin1);
28 } else
29 c2ln(in, tin0, tin1, l);
30
31 tin0 ^= tout0;
32 tin[0] = tin0;
33 tin1 ^= tout1;
34 tin[1] = tin1;
35 DES_encrypt1((DES_LONG *)tin, schedule, DES_ENCRYPT);
36 tout0 = tin[0];
37 tout1 = tin[1];
38 }
39 if (out != NULL) {
40 l2c(tout0, out);
41 l2c(tout1, out);
42 }
43 tout0 = tin0 = tin1 = tin[0] = tin[1] = 0;
44 /*
45 * Transform the data in tout1 so that it will match the return value
46 * that the MIT Kerberos mit_des_cbc_cksum API returns.
47 */
48 tout1 = ((tout1 >> 24L) & 0x000000FF)
49 | ((tout1 >> 8L) & 0x0000FF00)
50 | ((tout1 << 8L) & 0x00FF0000)
51 | ((tout1 << 24L) & 0xFF000000);
52 return tout1;
53}
54