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 <openssl/rc2.h>
11#include "rc2_local.h"
12
13void RC2_cbc_encrypt(const unsigned char *in, unsigned char *out, long length,
14 RC2_KEY *ks, unsigned char *iv, int encrypt)
15{
16 register unsigned long tin0, tin1;
17 register unsigned long tout0, tout1, xor0, xor1;
18 register long l = length;
19 unsigned long tin[2];
20
21 if (encrypt) {
22 c2l(iv, tout0);
23 c2l(iv, tout1);
24 iv -= 8;
25 for (l -= 8; l >= 0; l -= 8) {
26 c2l(in, tin0);
27 c2l(in, tin1);
28 tin0 ^= tout0;
29 tin1 ^= tout1;
30 tin[0] = tin0;
31 tin[1] = tin1;
32 RC2_encrypt(tin, ks);
33 tout0 = tin[0];
34 l2c(tout0, out);
35 tout1 = tin[1];
36 l2c(tout1, out);
37 }
38 if (l != -8) {
39 c2ln(in, tin0, tin1, l + 8);
40 tin0 ^= tout0;
41 tin1 ^= tout1;
42 tin[0] = tin0;
43 tin[1] = tin1;
44 RC2_encrypt(tin, ks);
45 tout0 = tin[0];
46 l2c(tout0, out);
47 tout1 = tin[1];
48 l2c(tout1, out);
49 }
50 l2c(tout0, iv);
51 l2c(tout1, iv);
52 } else {
53 c2l(iv, xor0);
54 c2l(iv, xor1);
55 iv -= 8;
56 for (l -= 8; l >= 0; l -= 8) {
57 c2l(in, tin0);
58 tin[0] = tin0;
59 c2l(in, tin1);
60 tin[1] = tin1;
61 RC2_decrypt(tin, ks);
62 tout0 = tin[0] ^ xor0;
63 tout1 = tin[1] ^ xor1;
64 l2c(tout0, out);
65 l2c(tout1, out);
66 xor0 = tin0;
67 xor1 = tin1;
68 }
69 if (l != -8) {
70 c2l(in, tin0);
71 tin[0] = tin0;
72 c2l(in, tin1);
73 tin[1] = tin1;
74 RC2_decrypt(tin, ks);
75 tout0 = tin[0] ^ xor0;
76 tout1 = tin[1] ^ xor1;
77 l2cn(tout0, tout1, out, l + 8);
78 xor0 = tin0;
79 xor1 = tin1;
80 }
81 l2c(xor0, iv);
82 l2c(xor1, iv);
83 }
84 tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0;
85 tin[0] = tin[1] = 0;
86}
87
88void RC2_encrypt(unsigned long *d, RC2_KEY *key)
89{
90 int i, n;
91 register RC2_INT *p0, *p1;
92 register RC2_INT x0, x1, x2, x3, t;
93 unsigned long l;
94
95 l = d[0];
96 x0 = (RC2_INT) l & 0xffff;
97 x1 = (RC2_INT) (l >> 16L);
98 l = d[1];
99 x2 = (RC2_INT) l & 0xffff;
100 x3 = (RC2_INT) (l >> 16L);
101
102 n = 3;
103 i = 5;
104
105 p0 = p1 = &(key->data[0]);
106 for (;;) {
107 t = (x0 + (x1 & ~x3) + (x2 & x3) + *(p0++)) & 0xffff;
108 x0 = (t << 1) | (t >> 15);
109 t = (x1 + (x2 & ~x0) + (x3 & x0) + *(p0++)) & 0xffff;
110 x1 = (t << 2) | (t >> 14);
111 t = (x2 + (x3 & ~x1) + (x0 & x1) + *(p0++)) & 0xffff;
112 x2 = (t << 3) | (t >> 13);
113 t = (x3 + (x0 & ~x2) + (x1 & x2) + *(p0++)) & 0xffff;
114 x3 = (t << 5) | (t >> 11);
115
116 if (--i == 0) {
117 if (--n == 0)
118 break;
119 i = (n == 2) ? 6 : 5;
120
121 x0 += p1[x3 & 0x3f];
122 x1 += p1[x0 & 0x3f];
123 x2 += p1[x1 & 0x3f];
124 x3 += p1[x2 & 0x3f];
125 }
126 }
127
128 d[0] =
129 (unsigned long)(x0 & 0xffff) | ((unsigned long)(x1 & 0xffff) << 16L);
130 d[1] =
131 (unsigned long)(x2 & 0xffff) | ((unsigned long)(x3 & 0xffff) << 16L);
132}
133
134void RC2_decrypt(unsigned long *d, RC2_KEY *key)
135{
136 int i, n;
137 register RC2_INT *p0, *p1;
138 register RC2_INT x0, x1, x2, x3, t;
139 unsigned long l;
140
141 l = d[0];
142 x0 = (RC2_INT) l & 0xffff;
143 x1 = (RC2_INT) (l >> 16L);
144 l = d[1];
145 x2 = (RC2_INT) l & 0xffff;
146 x3 = (RC2_INT) (l >> 16L);
147
148 n = 3;
149 i = 5;
150
151 p0 = &(key->data[63]);
152 p1 = &(key->data[0]);
153 for (;;) {
154 t = ((x3 << 11) | (x3 >> 5)) & 0xffff;
155 x3 = (t - (x0 & ~x2) - (x1 & x2) - *(p0--)) & 0xffff;
156 t = ((x2 << 13) | (x2 >> 3)) & 0xffff;
157 x2 = (t - (x3 & ~x1) - (x0 & x1) - *(p0--)) & 0xffff;
158 t = ((x1 << 14) | (x1 >> 2)) & 0xffff;
159 x1 = (t - (x2 & ~x0) - (x3 & x0) - *(p0--)) & 0xffff;
160 t = ((x0 << 15) | (x0 >> 1)) & 0xffff;
161 x0 = (t - (x1 & ~x3) - (x2 & x3) - *(p0--)) & 0xffff;
162
163 if (--i == 0) {
164 if (--n == 0)
165 break;
166 i = (n == 2) ? 6 : 5;
167
168 x3 = (x3 - p1[x2 & 0x3f]) & 0xffff;
169 x2 = (x2 - p1[x1 & 0x3f]) & 0xffff;
170 x1 = (x1 - p1[x0 & 0x3f]) & 0xffff;
171 x0 = (x0 - p1[x3 & 0x3f]) & 0xffff;
172 }
173 }
174
175 d[0] =
176 (unsigned long)(x0 & 0xffff) | ((unsigned long)(x1 & 0xffff) << 16L);
177 d[1] =
178 (unsigned long)(x2 & 0xffff) | ((unsigned long)(x3 & 0xffff) << 16L);
179}
180