1 /* $OpenBSD: rc2_cbc.c,v 1.8 2023/07/07 13:40:44 beck Exp $ */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58
59 #include <openssl/rc2.h>
60 #include "rc2_local.h"
61
62 void
RC2_cbc_encrypt(const unsigned char * in,unsigned char * out,long length,RC2_KEY * ks,unsigned char * iv,int encrypt)63 RC2_cbc_encrypt(const unsigned char *in, unsigned char *out, long length,
64 RC2_KEY *ks, unsigned char *iv, int encrypt)
65 {
66 unsigned long tin0, tin1;
67 unsigned long tout0, tout1, xor0, xor1;
68 long l = length;
69 unsigned long tin[2];
70
71 if (encrypt) {
72 c2l(iv, tout0);
73 c2l(iv, tout1);
74 iv -= 8;
75 for (l -= 8; l >= 0; l -= 8)
76 {
77 c2l(in, tin0);
78 c2l(in, tin1);
79 tin0 ^= tout0;
80 tin1 ^= tout1;
81 tin[0] = tin0;
82 tin[1] = tin1;
83 RC2_encrypt(tin, ks);
84 tout0 = tin[0];
85 l2c(tout0, out);
86 tout1 = tin[1];
87 l2c(tout1, out);
88 }
89 if (l != -8) {
90 c2ln(in, tin0, tin1, l + 8);
91 tin0 ^= tout0;
92 tin1 ^= tout1;
93 tin[0] = tin0;
94 tin[1] = tin1;
95 RC2_encrypt(tin, ks);
96 tout0 = tin[0];
97 l2c(tout0, out);
98 tout1 = tin[1];
99 l2c(tout1, out);
100 }
101 l2c(tout0, iv);
102 l2c(tout1, iv);
103 } else {
104 c2l(iv, xor0);
105 c2l(iv, xor1);
106 iv -= 8;
107 for (l -= 8; l >= 0; l -= 8)
108 {
109 c2l(in, tin0);
110 tin[0] = tin0;
111 c2l(in, tin1);
112 tin[1] = tin1;
113 RC2_decrypt(tin, ks);
114 tout0 = tin[0] ^ xor0;
115 tout1 = tin[1] ^ xor1;
116 l2c(tout0, out);
117 l2c(tout1, out);
118 xor0 = tin0;
119 xor1 = tin1;
120 }
121 if (l != -8) {
122 c2l(in, tin0);
123 tin[0] = tin0;
124 c2l(in, tin1);
125 tin[1] = tin1;
126 RC2_decrypt(tin, ks);
127 tout0 = tin[0] ^ xor0;
128 tout1 = tin[1] ^ xor1;
129 l2cn(tout0, tout1, out, l + 8);
130 xor0 = tin0;
131 xor1 = tin1;
132 }
133 l2c(xor0, iv);
134 l2c(xor1, iv);
135 }
136 tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0;
137 tin[0] = tin[1] = 0;
138 }
139 LCRYPTO_ALIAS(RC2_cbc_encrypt);
140
141 void
RC2_encrypt(unsigned long * d,RC2_KEY * key)142 RC2_encrypt(unsigned long *d, RC2_KEY *key)
143 {
144 int i, n;
145 RC2_INT *p0, *p1;
146 RC2_INT x0, x1, x2, x3, t;
147 unsigned long l;
148
149 l = d[0];
150 x0 = (RC2_INT)l & 0xffff;
151 x1 = (RC2_INT)(l >> 16L);
152 l = d[1];
153 x2 = (RC2_INT)l & 0xffff;
154 x3 = (RC2_INT)(l >> 16L);
155
156 n = 3;
157 i = 5;
158
159 p0 = p1 = &(key->data[0]);
160 for (;;) {
161 t = (x0 + (x1 & ~x3) + (x2 & x3) + *(p0++)) & 0xffff;
162 x0 = (t << 1)|(t >> 15);
163 t = (x1 + (x2 & ~x0) + (x3 & x0) + *(p0++)) & 0xffff;
164 x1 = (t << 2)|(t >> 14);
165 t = (x2 + (x3 & ~x1) + (x0 & x1) + *(p0++)) & 0xffff;
166 x2 = (t << 3)|(t >> 13);
167 t = (x3 + (x0 & ~x2) + (x1 & x2) + *(p0++)) & 0xffff;
168 x3 = (t << 5)|(t >> 11);
169
170 if (--i == 0) {
171 if (--n == 0)
172 break;
173 i = (n == 2) ? 6 : 5;
174
175 x0 += p1[x3 & 0x3f];
176 x1 += p1[x0 & 0x3f];
177 x2 += p1[x1 & 0x3f];
178 x3 += p1[x2 & 0x3f];
179 }
180 }
181
182 d[0] = (unsigned long)(x0 & 0xffff)|((unsigned long)(x1 & 0xffff) <<
183 16L);
184 d[1] = (unsigned long)(x2 & 0xffff)|((unsigned long)(x3 & 0xffff) <<
185 16L);
186 }
187 LCRYPTO_ALIAS(RC2_encrypt);
188
189 void
RC2_decrypt(unsigned long * d,RC2_KEY * key)190 RC2_decrypt(unsigned long *d, RC2_KEY *key)
191 {
192 int i, n;
193 RC2_INT *p0, *p1;
194 RC2_INT x0, x1, x2, x3, t;
195 unsigned long l;
196
197 l = d[0];
198 x0 = (RC2_INT)l & 0xffff;
199 x1 = (RC2_INT)(l >> 16L);
200 l = d[1];
201 x2 = (RC2_INT)l & 0xffff;
202 x3 = (RC2_INT)(l >> 16L);
203
204 n = 3;
205 i = 5;
206
207 p0 = &(key->data[63]);
208 p1 = &(key->data[0]);
209 for (;;) {
210 t = ((x3 << 11)|(x3 >> 5)) & 0xffff;
211 x3 = (t - (x0 & ~x2) - (x1 & x2) - *(p0--)) & 0xffff;
212 t = ((x2 << 13)|(x2 >> 3)) & 0xffff;
213 x2 = (t - (x3 & ~x1) - (x0 & x1) - *(p0--)) & 0xffff;
214 t = ((x1 << 14)|(x1 >> 2)) & 0xffff;
215 x1 = (t - (x2 & ~x0) - (x3 & x0) - *(p0--)) & 0xffff;
216 t = ((x0 << 15)|(x0 >> 1)) & 0xffff;
217 x0 = (t - (x1 & ~x3) - (x2 & x3) - *(p0--)) & 0xffff;
218
219 if (--i == 0) {
220 if (--n == 0)
221 break;
222 i = (n == 2) ? 6 : 5;
223
224 x3 = (x3 - p1[x2 & 0x3f]) & 0xffff;
225 x2 = (x2 - p1[x1 & 0x3f]) & 0xffff;
226 x1 = (x1 - p1[x0 & 0x3f]) & 0xffff;
227 x0 = (x0 - p1[x3 & 0x3f]) & 0xffff;
228 }
229 }
230
231 d[0] = (unsigned long)(x0 & 0xffff)|((unsigned long)(x1 & 0xffff) <<
232 16L);
233 d[1] = (unsigned long)(x2 & 0xffff)|((unsigned long)(x3 & 0xffff) <<
234 16L);
235 }
236 LCRYPTO_ALIAS(RC2_decrypt);
237