1 /*
2 * Copyright 1995-2020 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 /*
11 * DES low level APIs are deprecated for public use, but still ok for internal
12 * use.
13 */
14 #include "internal/deprecated.h"
15
16 #include "des_local.h"
17
18 /*
19 * The input and output encrypted as though 64bit ofb mode is being used.
20 * The extra state information to record how much of the 64bit block we have
21 * used is contained in *num;
22 */
DES_ofb64_encrypt(register const unsigned char * in,register unsigned char * out,long length,DES_key_schedule * schedule,DES_cblock * ivec,int * num)23 void DES_ofb64_encrypt(register const unsigned char *in,
24 register unsigned char *out, long length,
25 DES_key_schedule *schedule, DES_cblock *ivec, int *num)
26 {
27 register DES_LONG v0, v1, t;
28 register int n = *num;
29 register long l = length;
30 DES_cblock d;
31 register unsigned char *dp;
32 DES_LONG ti[2];
33 unsigned char *iv;
34 int save = 0;
35
36 iv = &(*ivec)[0];
37 c2l(iv, v0);
38 c2l(iv, v1);
39 ti[0] = v0;
40 ti[1] = v1;
41 dp = d;
42 l2c(v0, dp);
43 l2c(v1, dp);
44 while (l--) {
45 if (n == 0) {
46 DES_encrypt1(ti, schedule, DES_ENCRYPT);
47 dp = d;
48 t = ti[0];
49 l2c(t, dp);
50 t = ti[1];
51 l2c(t, dp);
52 save++;
53 }
54 *(out++) = *(in++) ^ d[n];
55 n = (n + 1) & 0x07;
56 }
57 if (save) {
58 v0 = ti[0];
59 v1 = ti[1];
60 iv = &(*ivec)[0];
61 l2c(v0, iv);
62 l2c(v1, iv);
63 }
64 t = v0 = v1 = ti[0] = ti[1] = 0;
65 *num = n;
66 }
67
