ncbc_enc.c revision 296465 
1/* crypto/des/ncbc_enc.c */
2/*-
3 * #included by:
4 *    cbc_enc.c  (DES_cbc_encrypt)
5 *    des_enc.c  (DES_ncbc_encrypt)
6 */
7/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
8 * All rights reserved.
9 *
10 * This package is an SSL implementation written
11 * by Eric Young (eay@cryptsoft.com).
12 * The implementation was written so as to conform with Netscapes SSL.
13 *
14 * This library is free for commercial and non-commercial use as long as
15 * the following conditions are aheared to.  The following conditions
16 * apply to all code found in this distribution, be it the RC4, RSA,
17 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
18 * included with this distribution is covered by the same copyright terms
19 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
20 *
21 * Copyright remains Eric Young's, and as such any Copyright notices in
22 * the code are not to be removed.
23 * If this package is used in a product, Eric Young should be given attribution
24 * as the author of the parts of the library used.
25 * This can be in the form of a textual message at program startup or
26 * in documentation (online or textual) provided with the package.
27 *
28 * Redistribution and use in source and binary forms, with or without
29 * modification, are permitted provided that the following conditions
30 * are met:
31 * 1. Redistributions of source code must retain the copyright
32 *    notice, this list of conditions and the following disclaimer.
33 * 2. Redistributions in binary form must reproduce the above copyright
34 *    notice, this list of conditions and the following disclaimer in the
35 *    documentation and/or other materials provided with the distribution.
36 * 3. All advertising materials mentioning features or use of this software
37 *    must display the following acknowledgement:
38 *    "This product includes cryptographic software written by
39 *     Eric Young (eay@cryptsoft.com)"
40 *    The word 'cryptographic' can be left out if the rouines from the library
41 *    being used are not cryptographic related :-).
42 * 4. If you include any Windows specific code (or a derivative thereof) from
43 *    the apps directory (application code) you must include an acknowledgement:
44 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
45 *
46 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
47 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
48 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
49 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
50 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
51 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
52 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
53 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
54 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
55 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
56 * SUCH DAMAGE.
57 *
58 * The licence and distribution terms for any publically available version or
59 * derivative of this code cannot be changed.  i.e. this code cannot simply be
60 * copied and put under another distribution licence
61 * [including the GNU Public Licence.]
62 */
63
64#include "des_locl.h"
65
66#ifdef CBC_ENC_C__DONT_UPDATE_IV
67void DES_cbc_encrypt(const unsigned char *in, unsigned char *out, long length,
68                     DES_key_schedule *_schedule, DES_cblock *ivec, int enc)
69#else
70void DES_ncbc_encrypt(const unsigned char *in, unsigned char *out,
71                      long length, DES_key_schedule *_schedule,
72                      DES_cblock *ivec, int enc)
73#endif
74{
75    register DES_LONG tin0, tin1;
76    register DES_LONG tout0, tout1, xor0, xor1;
77    register long l = length;
78    DES_LONG tin[2];
79    unsigned char *iv;
80
81    iv = &(*ivec)[0];
82
83    if (enc) {
84        c2l(iv, tout0);
85        c2l(iv, tout1);
86        for (l -= 8; l >= 0; l -= 8) {
87            c2l(in, tin0);
88            c2l(in, tin1);
89            tin0 ^= tout0;
90            tin[0] = tin0;
91            tin1 ^= tout1;
92            tin[1] = tin1;
93            DES_encrypt1((DES_LONG *)tin, _schedule, DES_ENCRYPT);
94            tout0 = tin[0];
95            l2c(tout0, out);
96            tout1 = tin[1];
97            l2c(tout1, out);
98        }
99        if (l != -8) {
100            c2ln(in, tin0, tin1, l + 8);
101            tin0 ^= tout0;
102            tin[0] = tin0;
103            tin1 ^= tout1;
104            tin[1] = tin1;
105            DES_encrypt1((DES_LONG *)tin, _schedule, DES_ENCRYPT);
106            tout0 = tin[0];
107            l2c(tout0, out);
108            tout1 = tin[1];
109            l2c(tout1, out);
110        }
111#ifndef CBC_ENC_C__DONT_UPDATE_IV
112        iv = &(*ivec)[0];
113        l2c(tout0, iv);
114        l2c(tout1, iv);
115#endif
116    } else {
117        c2l(iv, xor0);
118        c2l(iv, xor1);
119        for (l -= 8; l >= 0; l -= 8) {
120            c2l(in, tin0);
121            tin[0] = tin0;
122            c2l(in, tin1);
123            tin[1] = tin1;
124            DES_encrypt1((DES_LONG *)tin, _schedule, DES_DECRYPT);
125            tout0 = tin[0] ^ xor0;
126            tout1 = tin[1] ^ xor1;
127            l2c(tout0, out);
128            l2c(tout1, out);
129            xor0 = tin0;
130            xor1 = tin1;
131        }
132        if (l != -8) {
133            c2l(in, tin0);
134            tin[0] = tin0;
135            c2l(in, tin1);
136            tin[1] = tin1;
137            DES_encrypt1((DES_LONG *)tin, _schedule, DES_DECRYPT);
138            tout0 = tin[0] ^ xor0;
139            tout1 = tin[1] ^ xor1;
140            l2cn(tout0, tout1, out, l + 8);
141#ifndef CBC_ENC_C__DONT_UPDATE_IV
142            xor0 = tin0;
143            xor1 = tin1;
144#endif
145        }
146#ifndef CBC_ENC_C__DONT_UPDATE_IV
147        iv = &(*ivec)[0];
148        l2c(xor0, iv);
149        l2c(xor1, iv);
150#endif
151    }
152    tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0;
153    tin[0] = tin[1] = 0;
154}
155