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/cast.h>
11#include "cast_local.h"
12
13void CAST_encrypt(CAST_LONG *data, const CAST_KEY *key)
14{
15 CAST_LONG l, r, t;
16 const CAST_LONG *k;
17
18 k = &(key->data[0]);
19 l = data[0];
20 r = data[1];
21
22 E_CAST(0, k, l, r, +, ^, -);
23 E_CAST(1, k, r, l, ^, -, +);
24 E_CAST(2, k, l, r, -, +, ^);
25 E_CAST(3, k, r, l, +, ^, -);
26 E_CAST(4, k, l, r, ^, -, +);
27 E_CAST(5, k, r, l, -, +, ^);
28 E_CAST(6, k, l, r, +, ^, -);
29 E_CAST(7, k, r, l, ^, -, +);
30 E_CAST(8, k, l, r, -, +, ^);
31 E_CAST(9, k, r, l, +, ^, -);
32 E_CAST(10, k, l, r, ^, -, +);
33 E_CAST(11, k, r, l, -, +, ^);
34 if (!key->short_key) {
35 E_CAST(12, k, l, r, +, ^, -);
36 E_CAST(13, k, r, l, ^, -, +);
37 E_CAST(14, k, l, r, -, +, ^);
38 E_CAST(15, k, r, l, +, ^, -);
39 }
40
41 data[1] = l & 0xffffffffL;
42 data[0] = r & 0xffffffffL;
43}
44
45void CAST_decrypt(CAST_LONG *data, const CAST_KEY *key)
46{
47 CAST_LONG l, r, t;
48 const CAST_LONG *k;
49
50 k = &(key->data[0]);
51 l = data[0];
52 r = data[1];
53
54 if (!key->short_key) {
55 E_CAST(15, k, l, r, +, ^, -);
56 E_CAST(14, k, r, l, -, +, ^);
57 E_CAST(13, k, l, r, ^, -, +);
58 E_CAST(12, k, r, l, +, ^, -);
59 }
60 E_CAST(11, k, l, r, -, +, ^);
61 E_CAST(10, k, r, l, ^, -, +);
62 E_CAST(9, k, l, r, +, ^, -);
63 E_CAST(8, k, r, l, -, +, ^);
64 E_CAST(7, k, l, r, ^, -, +);
65 E_CAST(6, k, r, l, +, ^, -);
66 E_CAST(5, k, l, r, -, +, ^);
67 E_CAST(4, k, r, l, ^, -, +);
68 E_CAST(3, k, l, r, +, ^, -);
69 E_CAST(2, k, r, l, -, +, ^);
70 E_CAST(1, k, l, r, ^, -, +);
71 E_CAST(0, k, r, l, +, ^, -);
72
73 data[1] = l & 0xffffffffL;
74 data[0] = r & 0xffffffffL;
75}
76
77void CAST_cbc_encrypt(const unsigned char *in, unsigned char *out,
78 long length, const CAST_KEY *ks, unsigned char *iv,
79 int enc)
80{
81 register CAST_LONG tin0, tin1;
82 register CAST_LONG tout0, tout1, xor0, xor1;
83 register long l = length;
84 CAST_LONG tin[2];
85
86 if (enc) {
87 n2l(iv, tout0);
88 n2l(iv, tout1);
89 iv -= 8;
90 for (l -= 8; l >= 0; l -= 8) {
91 n2l(in, tin0);
92 n2l(in, tin1);
93 tin0 ^= tout0;
94 tin1 ^= tout1;
95 tin[0] = tin0;
96 tin[1] = tin1;
97 CAST_encrypt(tin, ks);
98 tout0 = tin[0];
99 tout1 = tin[1];
100 l2n(tout0, out);
101 l2n(tout1, out);
102 }
103 if (l != -8) {
104 n2ln(in, tin0, tin1, l + 8);
105 tin0 ^= tout0;
106 tin1 ^= tout1;
107 tin[0] = tin0;
108 tin[1] = tin1;
109 CAST_encrypt(tin, ks);
110 tout0 = tin[0];
111 tout1 = tin[1];
112 l2n(tout0, out);
113 l2n(tout1, out);
114 }
115 l2n(tout0, iv);
116 l2n(tout1, iv);
117 } else {
118 n2l(iv, xor0);
119 n2l(iv, xor1);
120 iv -= 8;
121 for (l -= 8; l >= 0; l -= 8) {
122 n2l(in, tin0);
123 n2l(in, tin1);
124 tin[0] = tin0;
125 tin[1] = tin1;
126 CAST_decrypt(tin, ks);
127 tout0 = tin[0] ^ xor0;
128 tout1 = tin[1] ^ xor1;
129 l2n(tout0, out);
130 l2n(tout1, out);
131 xor0 = tin0;
132 xor1 = tin1;
133 }
134 if (l != -8) {
135 n2l(in, tin0);
136 n2l(in, tin1);
137 tin[0] = tin0;
138 tin[1] = tin1;
139 CAST_decrypt(tin, ks);
140 tout0 = tin[0] ^ xor0;
141 tout1 = tin[1] ^ xor1;
142 l2nn(tout0, tout1, out, l + 8);
143 xor0 = tin0;
144 xor1 = tin1;
145 }
146 l2n(xor0, iv);
147 l2n(xor1, iv);
148 }
149 tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0;
150 tin[0] = tin[1] = 0;
151}
152