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 */
23void DES_ede3_ofb64_encrypt(register const unsigned char *in,
24                            register unsigned char *out, long length,
25                            DES_key_schedule *k1, DES_key_schedule *k2,
26                            DES_key_schedule *k3, DES_cblock *ivec, int *num)
27{
28    register DES_LONG v0, v1;
29    register int n = *num;
30    register long l = length;
31    DES_cblock d;
32    register char *dp;
33    DES_LONG ti[2];
34    unsigned char *iv;
35    int save = 0;
36
37    iv = &(*ivec)[0];
38    c2l(iv, v0);
39    c2l(iv, v1);
40    ti[0] = v0;
41    ti[1] = v1;
42    dp = (char *)d;
43    l2c(v0, dp);
44    l2c(v1, dp);
45    while (l--) {
46        if (n == 0) {
47            /* ti[0]=v0; */
48            /* ti[1]=v1; */
49            DES_encrypt3(ti, k1, k2, k3);
50            v0 = ti[0];
51            v1 = ti[1];
52
53            dp = (char *)d;
54            l2c(v0, dp);
55            l2c(v1, dp);
56            save++;
57        }
58        *(out++) = *(in++) ^ d[n];
59        n = (n + 1) & 0x07;
60    }
61    if (save) {
62        iv = &(*ivec)[0];
63        l2c(v0, iv);
64        l2c(v1, iv);
65    }
66    v0 = v1 = ti[0] = ti[1] = 0;
67    *num = n;
68}
69