1 /* FCrypt encryption algorithm
2 *
3 * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 *
11 * Based on code:
12 *
13 * Copyright (c) 1995 - 2000 Kungliga Tekniska Högskolan
14 * (Royal Institute of Technology, Stockholm, Sweden).
15 * All rights reserved.
16 *
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions
19 * are met:
20 *
21 * 1. Redistributions of source code must retain the above copyright
22 * notice, this list of conditions and the following disclaimer.
23 *
24 * 2. Redistributions in binary form must reproduce the above copyright
25 * notice, this list of conditions and the following disclaimer in the
26 * documentation and/or other materials provided with the distribution.
27 *
28 * 3. Neither the name of the Institute nor the names of its contributors
29 * may be used to endorse or promote products derived from this software
30 * without specific prior written permission.
31 *
32 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
33 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
34 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
35 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
36 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
40 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
41 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
42 * SUCH DAMAGE.
43 */
44
45 #include <asm/byteorder.h>
46 #include <linux/bitops.h>
47 #include <linux/init.h>
48 #include <linux/module.h>
49 #include <linux/crypto.h>
50
51 #define ROUNDS 16
52
53 struct fcrypt_ctx {
54 __be32 sched[ROUNDS];
55 };
56
57 /* Rotate right two 32 bit numbers as a 56 bit number */
58 #define ror56(hi, lo, n) \
59 do { \
60 u32 t = lo & ((1 << n) - 1); \
61 lo = (lo >> n) | ((hi & ((1 << n) - 1)) << (32 - n)); \
62 hi = (hi >> n) | (t << (24-n)); \
63 } while (0)
64
65 /* Rotate right one 64 bit number as a 56 bit number */
66 #define ror56_64(k, n) \
67 do { \
68 k = (k >> n) | ((k & ((1 << n) - 1)) << (56 - n)); \
69 } while (0)
70
71 /*
72 * Sboxes for Feistel network derived from
73 * /afs/transarc.com/public/afsps/afs.rel31b.export-src/rxkad/sboxes.h
74 */
75 #undef Z
76 #define Z(x) cpu_to_be32(x << 3)
77 static const __be32 sbox0[256] = {
78 Z(0xea), Z(0x7f), Z(0xb2), Z(0x64), Z(0x9d), Z(0xb0), Z(0xd9), Z(0x11),
79 Z(0xcd), Z(0x86), Z(0x86), Z(0x91), Z(0x0a), Z(0xb2), Z(0x93), Z(0x06),
80 Z(0x0e), Z(0x06), Z(0xd2), Z(0x65), Z(0x73), Z(0xc5), Z(0x28), Z(0x60),
81 Z(0xf2), Z(0x20), Z(0xb5), Z(0x38), Z(0x7e), Z(0xda), Z(0x9f), Z(0xe3),
82 Z(0xd2), Z(0xcf), Z(0xc4), Z(0x3c), Z(0x61), Z(0xff), Z(0x4a), Z(0x4a),
83 Z(0x35), Z(0xac), Z(0xaa), Z(0x5f), Z(0x2b), Z(0xbb), Z(0xbc), Z(0x53),
84 Z(0x4e), Z(0x9d), Z(0x78), Z(0xa3), Z(0xdc), Z(0x09), Z(0x32), Z(0x10),
85 Z(0xc6), Z(0x6f), Z(0x66), Z(0xd6), Z(0xab), Z(0xa9), Z(0xaf), Z(0xfd),
86 Z(0x3b), Z(0x95), Z(0xe8), Z(0x34), Z(0x9a), Z(0x81), Z(0x72), Z(0x80),
87 Z(0x9c), Z(0xf3), Z(0xec), Z(0xda), Z(0x9f), Z(0x26), Z(0x76), Z(0x15),
88 Z(0x3e), Z(0x55), Z(0x4d), Z(0xde), Z(0x84), Z(0xee), Z(0xad), Z(0xc7),
89 Z(0xf1), Z(0x6b), Z(0x3d), Z(0xd3), Z(0x04), Z(0x49), Z(0xaa), Z(0x24),
90 Z(0x0b), Z(0x8a), Z(0x83), Z(0xba), Z(0xfa), Z(0x85), Z(0xa0), Z(0xa8),
91 Z(0xb1), Z(0xd4), Z(0x01), Z(0xd8), Z(0x70), Z(0x64), Z(0xf0), Z(0x51),
92 Z(0xd2), Z(0xc3), Z(0xa7), Z(0x75), Z(0x8c), Z(0xa5), Z(0x64), Z(0xef),
93 Z(0x10), Z(0x4e), Z(0xb7), Z(0xc6), Z(0x61), Z(0x03), Z(0xeb), Z(0x44),
94 Z(0x3d), Z(0xe5), Z(0xb3), Z(0x5b), Z(0xae), Z(0xd5), Z(0xad), Z(0x1d),
95 Z(0xfa), Z(0x5a), Z(0x1e), Z(0x33), Z(0xab), Z(0x93), Z(0xa2), Z(0xb7),
96 Z(0xe7), Z(0xa8), Z(0x45), Z(0xa4), Z(0xcd), Z(0x29), Z(0x63), Z(0x44),
97 Z(0xb6), Z(0x69), Z(0x7e), Z(0x2e), Z(0x62), Z(0x03), Z(0xc8), Z(0xe0),
98 Z(0x17), Z(0xbb), Z(0xc7), Z(0xf3), Z(0x3f), Z(0x36), Z(0xba), Z(0x71),
99 Z(0x8e), Z(0x97), Z(0x65), Z(0x60), Z(0x69), Z(0xb6), Z(0xf6), Z(0xe6),
100 Z(0x6e), Z(0xe0), Z(0x81), Z(0x59), Z(0xe8), Z(0xaf), Z(0xdd), Z(0x95),
101 Z(0x22), Z(0x99), Z(0xfd), Z(0x63), Z(0x19), Z(0x74), Z(0x61), Z(0xb1),
102 Z(0xb6), Z(0x5b), Z(0xae), Z(0x54), Z(0xb3), Z(0x70), Z(0xff), Z(0xc6),
103 Z(0x3b), Z(0x3e), Z(0xc1), Z(0xd7), Z(0xe1), Z(0x0e), Z(0x76), Z(0xe5),
104 Z(0x36), Z(0x4f), Z(0x59), Z(0xc7), Z(0x08), Z(0x6e), Z(0x82), Z(0xa6),
105 Z(0x93), Z(0xc4), Z(0xaa), Z(0x26), Z(0x49), Z(0xe0), Z(0x21), Z(0x64),
106 Z(0x07), Z(0x9f), Z(0x64), Z(0x81), Z(0x9c), Z(0xbf), Z(0xf9), Z(0xd1),
107 Z(0x43), Z(0xf8), Z(0xb6), Z(0xb9), Z(0xf1), Z(0x24), Z(0x75), Z(0x03),
108 Z(0xe4), Z(0xb0), Z(0x99), Z(0x46), Z(0x3d), Z(0xf5), Z(0xd1), Z(0x39),
109 Z(0x72), Z(0x12), Z(0xf6), Z(0xba), Z(0x0c), Z(0x0d), Z(0x42), Z(0x2e)
110 };
111
112 #undef Z
113 #define Z(x) cpu_to_be32((x << 27) | (x >> 5))
114 static const __be32 sbox1[256] = {
115 Z(0x77), Z(0x14), Z(0xa6), Z(0xfe), Z(0xb2), Z(0x5e), Z(0x8c), Z(0x3e),
116 Z(0x67), Z(0x6c), Z(0xa1), Z(0x0d), Z(0xc2), Z(0xa2), Z(0xc1), Z(0x85),
117 Z(0x6c), Z(0x7b), Z(0x67), Z(0xc6), Z(0x23), Z(0xe3), Z(0xf2), Z(0x89),
118 Z(0x50), Z(0x9c), Z(0x03), Z(0xb7), Z(0x73), Z(0xe6), Z(0xe1), Z(0x39),
119 Z(0x31), Z(0x2c), Z(0x27), Z(0x9f), Z(0xa5), Z(0x69), Z(0x44), Z(0xd6),
120 Z(0x23), Z(0x83), Z(0x98), Z(0x7d), Z(0x3c), Z(0xb4), Z(0x2d), Z(0x99),
121 Z(0x1c), Z(0x1f), Z(0x8c), Z(0x20), Z(0x03), Z(0x7c), Z(0x5f), Z(0xad),
122 Z(0xf4), Z(0xfa), Z(0x95), Z(0xca), Z(0x76), Z(0x44), Z(0xcd), Z(0xb6),
123 Z(0xb8), Z(0xa1), Z(0xa1), Z(0xbe), Z(0x9e), Z(0x54), Z(0x8f), Z(0x0b),
124 Z(0x16), Z(0x74), Z(0x31), Z(0x8a), Z(0x23), Z(0x17), Z(0x04), Z(0xfa),
125 Z(0x79), Z(0x84), Z(0xb1), Z(0xf5), Z(0x13), Z(0xab), Z(0xb5), Z(0x2e),
126 Z(0xaa), Z(0x0c), Z(0x60), Z(0x6b), Z(0x5b), Z(0xc4), Z(0x4b), Z(0xbc),
127 Z(0xe2), Z(0xaf), Z(0x45), Z(0x73), Z(0xfa), Z(0xc9), Z(0x49), Z(0xcd),
128 Z(0x00), Z(0x92), Z(0x7d), Z(0x97), Z(0x7a), Z(0x18), Z(0x60), Z(0x3d),
129 Z(0xcf), Z(0x5b), Z(0xde), Z(0xc6), Z(0xe2), Z(0xe6), Z(0xbb), Z(0x8b),
130 Z(0x06), Z(0xda), Z(0x08), Z(0x15), Z(0x1b), Z(0x88), Z(0x6a), Z(0x17),
131 Z(0x89), Z(0xd0), Z(0xa9), Z(0xc1), Z(0xc9), Z(0x70), Z(0x6b), Z(0xe5),
132 Z(0x43), Z(0xf4), Z(0x68), Z(0xc8), Z(0xd3), Z(0x84), Z(0x28), Z(0x0a),
133 Z(0x52), Z(0x66), Z(0xa3), Z(0xca), Z(0xf2), Z(0xe3), Z(0x7f), Z(0x7a),
134 Z(0x31), Z(0xf7), Z(0x88), Z(0x94), Z(0x5e), Z(0x9c), Z(0x63), Z(0xd5),
135 Z(0x24), Z(0x66), Z(0xfc), Z(0xb3), Z(0x57), Z(0x25), Z(0xbe), Z(0x89),
136 Z(0x44), Z(0xc4), Z(0xe0), Z(0x8f), Z(0x23), Z(0x3c), Z(0x12), Z(0x52),
137 Z(0xf5), Z(0x1e), Z(0xf4), Z(0xcb), Z(0x18), Z(0x33), Z(0x1f), Z(0xf8),
138 Z(0x69), Z(0x10), Z(0x9d), Z(0xd3), Z(0xf7), Z(0x28), Z(0xf8), Z(0x30),
139 Z(0x05), Z(0x5e), Z(0x32), Z(0xc0), Z(0xd5), Z(0x19), Z(0xbd), Z(0x45),
140 Z(0x8b), Z(0x5b), Z(0xfd), Z(0xbc), Z(0xe2), Z(0x5c), Z(0xa9), Z(0x96),
141 Z(0xef), Z(0x70), Z(0xcf), Z(0xc2), Z(0x2a), Z(0xb3), Z(0x61), Z(0xad),
142 Z(0x80), Z(0x48), Z(0x81), Z(0xb7), Z(0x1d), Z(0x43), Z(0xd9), Z(0xd7),
143 Z(0x45), Z(0xf0), Z(0xd8), Z(0x8a), Z(0x59), Z(0x7c), Z(0x57), Z(0xc1),
144 Z(0x79), Z(0xc7), Z(0x34), Z(0xd6), Z(0x43), Z(0xdf), Z(0xe4), Z(0x78),
145 Z(0x16), Z(0x06), Z(0xda), Z(0x92), Z(0x76), Z(0x51), Z(0xe1), Z(0xd4),
146 Z(0x70), Z(0x03), Z(0xe0), Z(0x2f), Z(0x96), Z(0x91), Z(0x82), Z(0x80)
147 };
148
149 #undef Z
150 #define Z(x) cpu_to_be32(x << 11)
151 static const __be32 sbox2[256] = {
152 Z(0xf0), Z(0x37), Z(0x24), Z(0x53), Z(0x2a), Z(0x03), Z(0x83), Z(0x86),
153 Z(0xd1), Z(0xec), Z(0x50), Z(0xf0), Z(0x42), Z(0x78), Z(0x2f), Z(0x6d),
154 Z(0xbf), Z(0x80), Z(0x87), Z(0x27), Z(0x95), Z(0xe2), Z(0xc5), Z(0x5d),
155 Z(0xf9), Z(0x6f), Z(0xdb), Z(0xb4), Z(0x65), Z(0x6e), Z(0xe7), Z(0x24),
156 Z(0xc8), Z(0x1a), Z(0xbb), Z(0x49), Z(0xb5), Z(0x0a), Z(0x7d), Z(0xb9),
157 Z(0xe8), Z(0xdc), Z(0xb7), Z(0xd9), Z(0x45), Z(0x20), Z(0x1b), Z(0xce),
158 Z(0x59), Z(0x9d), Z(0x6b), Z(0xbd), Z(0x0e), Z(0x8f), Z(0xa3), Z(0xa9),
159 Z(0xbc), Z(0x74), Z(0xa6), Z(0xf6), Z(0x7f), Z(0x5f), Z(0xb1), Z(0x68),
160 Z(0x84), Z(0xbc), Z(0xa9), Z(0xfd), Z(0x55), Z(0x50), Z(0xe9), Z(0xb6),
161 Z(0x13), Z(0x5e), Z(0x07), Z(0xb8), Z(0x95), Z(0x02), Z(0xc0), Z(0xd0),
162 Z(0x6a), Z(0x1a), Z(0x85), Z(0xbd), Z(0xb6), Z(0xfd), Z(0xfe), Z(0x17),
163 Z(0x3f), Z(0x09), Z(0xa3), Z(0x8d), Z(0xfb), Z(0xed), Z(0xda), Z(0x1d),
164 Z(0x6d), Z(0x1c), Z(0x6c), Z(0x01), Z(0x5a), Z(0xe5), Z(0x71), Z(0x3e),
165 Z(0x8b), Z(0x6b), Z(0xbe), Z(0x29), Z(0xeb), Z(0x12), Z(0x19), Z(0x34),
166 Z(0xcd), Z(0xb3), Z(0xbd), Z(0x35), Z(0xea), Z(0x4b), Z(0xd5), Z(0xae),
167 Z(0x2a), Z(0x79), Z(0x5a), Z(0xa5), Z(0x32), Z(0x12), Z(0x7b), Z(0xdc),
168 Z(0x2c), Z(0xd0), Z(0x22), Z(0x4b), Z(0xb1), Z(0x85), Z(0x59), Z(0x80),
169 Z(0xc0), Z(0x30), Z(0x9f), Z(0x73), Z(0xd3), Z(0x14), Z(0x48), Z(0x40),
170 Z(0x07), Z(0x2d), Z(0x8f), Z(0x80), Z(0x0f), Z(0xce), Z(0x0b), Z(0x5e),
171 Z(0xb7), Z(0x5e), Z(0xac), Z(0x24), Z(0x94), Z(0x4a), Z(0x18), Z(0x15),
172 Z(0x05), Z(0xe8), Z(0x02), Z(0x77), Z(0xa9), Z(0xc7), Z(0x40), Z(0x45),
173 Z(0x89), Z(0xd1), Z(0xea), Z(0xde), Z(0x0c), Z(0x79), Z(0x2a), Z(0x99),
174 Z(0x6c), Z(0x3e), Z(0x95), Z(0xdd), Z(0x8c), Z(0x7d), Z(0xad), Z(0x6f),
175 Z(0xdc), Z(0xff), Z(0xfd), Z(0x62), Z(0x47), Z(0xb3), Z(0x21), Z(0x8a),
176 Z(0xec), Z(0x8e), Z(0x19), Z(0x18), Z(0xb4), Z(0x6e), Z(0x3d), Z(0xfd),
177 Z(0x74), Z(0x54), Z(0x1e), Z(0x04), Z(0x85), Z(0xd8), Z(0xbc), Z(0x1f),
178 Z(0x56), Z(0xe7), Z(0x3a), Z(0x56), Z(0x67), Z(0xd6), Z(0xc8), Z(0xa5),
179 Z(0xf3), Z(0x8e), Z(0xde), Z(0xae), Z(0x37), Z(0x49), Z(0xb7), Z(0xfa),
180 Z(0xc8), Z(0xf4), Z(0x1f), Z(0xe0), Z(0x2a), Z(0x9b), Z(0x15), Z(0xd1),
181 Z(0x34), Z(0x0e), Z(0xb5), Z(0xe0), Z(0x44), Z(0x78), Z(0x84), Z(0x59),
182 Z(0x56), Z(0x68), Z(0x77), Z(0xa5), Z(0x14), Z(0x06), Z(0xf5), Z(0x2f),
183 Z(0x8c), Z(0x8a), Z(0x73), Z(0x80), Z(0x76), Z(0xb4), Z(0x10), Z(0x86)
184 };
185
186 #undef Z
187 #define Z(x) cpu_to_be32(x << 19)
188 static const __be32 sbox3[256] = {
189 Z(0xa9), Z(0x2a), Z(0x48), Z(0x51), Z(0x84), Z(0x7e), Z(0x49), Z(0xe2),
190 Z(0xb5), Z(0xb7), Z(0x42), Z(0x33), Z(0x7d), Z(0x5d), Z(0xa6), Z(0x12),
191 Z(0x44), Z(0x48), Z(0x6d), Z(0x28), Z(0xaa), Z(0x20), Z(0x6d), Z(0x57),
192 Z(0xd6), Z(0x6b), Z(0x5d), Z(0x72), Z(0xf0), Z(0x92), Z(0x5a), Z(0x1b),
193 Z(0x53), Z(0x80), Z(0x24), Z(0x70), Z(0x9a), Z(0xcc), Z(0xa7), Z(0x66),
194 Z(0xa1), Z(0x01), Z(0xa5), Z(0x41), Z(0x97), Z(0x41), Z(0x31), Z(0x82),
195 Z(0xf1), Z(0x14), Z(0xcf), Z(0x53), Z(0x0d), Z(0xa0), Z(0x10), Z(0xcc),
196 Z(0x2a), Z(0x7d), Z(0xd2), Z(0xbf), Z(0x4b), Z(0x1a), Z(0xdb), Z(0x16),
197 Z(0x47), Z(0xf6), Z(0x51), Z(0x36), Z(0xed), Z(0xf3), Z(0xb9), Z(0x1a),
198 Z(0xa7), Z(0xdf), Z(0x29), Z(0x43), Z(0x01), Z(0x54), Z(0x70), Z(0xa4),
199 Z(0xbf), Z(0xd4), Z(0x0b), Z(0x53), Z(0x44), Z(0x60), Z(0x9e), Z(0x23),
200 Z(0xa1), Z(0x18), Z(0x68), Z(0x4f), Z(0xf0), Z(0x2f), Z(0x82), Z(0xc2),
201 Z(0x2a), Z(0x41), Z(0xb2), Z(0x42), Z(0x0c), Z(0xed), Z(0x0c), Z(0x1d),
202 Z(0x13), Z(0x3a), Z(0x3c), Z(0x6e), Z(0x35), Z(0xdc), Z(0x60), Z(0x65),
203 Z(0x85), Z(0xe9), Z(0x64), Z(0x02), Z(0x9a), Z(0x3f), Z(0x9f), Z(0x87),
204 Z(0x96), Z(0xdf), Z(0xbe), Z(0xf2), Z(0xcb), Z(0xe5), Z(0x6c), Z(0xd4),
205 Z(0x5a), Z(0x83), Z(0xbf), Z(0x92), Z(0x1b), Z(0x94), Z(0x00), Z(0x42),
206 Z(0xcf), Z(0x4b), Z(0x00), Z(0x75), Z(0xba), Z(0x8f), Z(0x76), Z(0x5f),
207 Z(0x5d), Z(0x3a), Z(0x4d), Z(0x09), Z(0x12), Z(0x08), Z(0x38), Z(0x95),
208 Z(0x17), Z(0xe4), Z(0x01), Z(0x1d), Z(0x4c), Z(0xa9), Z(0xcc), Z(0x85),
209 Z(0x82), Z(0x4c), Z(0x9d), Z(0x2f), Z(0x3b), Z(0x66), Z(0xa1), Z(0x34),
210 Z(0x10), Z(0xcd), Z(0x59), Z(0x89), Z(0xa5), Z(0x31), Z(0xcf), Z(0x05),
211 Z(0xc8), Z(0x84), Z(0xfa), Z(0xc7), Z(0xba), Z(0x4e), Z(0x8b), Z(0x1a),
212 Z(0x19), Z(0xf1), Z(0xa1), Z(0x3b), Z(0x18), Z(0x12), Z(0x17), Z(0xb0),
213 Z(0x98), Z(0x8d), Z(0x0b), Z(0x23), Z(0xc3), Z(0x3a), Z(0x2d), Z(0x20),
214 Z(0xdf), Z(0x13), Z(0xa0), Z(0xa8), Z(0x4c), Z(0x0d), Z(0x6c), Z(0x2f),
215 Z(0x47), Z(0x13), Z(0x13), Z(0x52), Z(0x1f), Z(0x2d), Z(0xf5), Z(0x79),
216 Z(0x3d), Z(0xa2), Z(0x54), Z(0xbd), Z(0x69), Z(0xc8), Z(0x6b), Z(0xf3),
217 Z(0x05), Z(0x28), Z(0xf1), Z(0x16), Z(0x46), Z(0x40), Z(0xb0), Z(0x11),
218 Z(0xd3), Z(0xb7), Z(0x95), Z(0x49), Z(0xcf), Z(0xc3), Z(0x1d), Z(0x8f),
219 Z(0xd8), Z(0xe1), Z(0x73), Z(0xdb), Z(0xad), Z(0xc8), Z(0xc9), Z(0xa9),
220 Z(0xa1), Z(0xc2), Z(0xc5), Z(0xe3), Z(0xba), Z(0xfc), Z(0x0e), Z(0x25)
221 };
222
223 /*
224 * This is a 16 round Feistel network with permutation F_ENCRYPT
225 */
226 #define F_ENCRYPT(R, L, sched) \
227 do { \
228 union lc4 { __be32 l; u8 c[4]; } u; \
229 u.l = sched ^ R; \
230 L ^= sbox0[u.c[0]] ^ sbox1[u.c[1]] ^ sbox2[u.c[2]] ^ sbox3[u.c[3]]; \
231 } while (0)
232
233 /*
234 * encryptor
235 */
fcrypt_encrypt(struct crypto_tfm * tfm,u8 * dst,const u8 * src)236 static void fcrypt_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
237 {
238 const struct fcrypt_ctx *ctx = crypto_tfm_ctx(tfm);
239 struct {
240 __be32 l, r;
241 } X;
242
243 memcpy(&X, src, sizeof(X));
244
245 F_ENCRYPT(X.r, X.l, ctx->sched[0x0]);
246 F_ENCRYPT(X.l, X.r, ctx->sched[0x1]);
247 F_ENCRYPT(X.r, X.l, ctx->sched[0x2]);
248 F_ENCRYPT(X.l, X.r, ctx->sched[0x3]);
249 F_ENCRYPT(X.r, X.l, ctx->sched[0x4]);
250 F_ENCRYPT(X.l, X.r, ctx->sched[0x5]);
251 F_ENCRYPT(X.r, X.l, ctx->sched[0x6]);
252 F_ENCRYPT(X.l, X.r, ctx->sched[0x7]);
253 F_ENCRYPT(X.r, X.l, ctx->sched[0x8]);
254 F_ENCRYPT(X.l, X.r, ctx->sched[0x9]);
255 F_ENCRYPT(X.r, X.l, ctx->sched[0xa]);
256 F_ENCRYPT(X.l, X.r, ctx->sched[0xb]);
257 F_ENCRYPT(X.r, X.l, ctx->sched[0xc]);
258 F_ENCRYPT(X.l, X.r, ctx->sched[0xd]);
259 F_ENCRYPT(X.r, X.l, ctx->sched[0xe]);
260 F_ENCRYPT(X.l, X.r, ctx->sched[0xf]);
261
262 memcpy(dst, &X, sizeof(X));
263 }
264
265 /*
266 * decryptor
267 */
fcrypt_decrypt(struct crypto_tfm * tfm,u8 * dst,const u8 * src)268 static void fcrypt_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
269 {
270 const struct fcrypt_ctx *ctx = crypto_tfm_ctx(tfm);
271 struct {
272 __be32 l, r;
273 } X;
274
275 memcpy(&X, src, sizeof(X));
276
277 F_ENCRYPT(X.l, X.r, ctx->sched[0xf]);
278 F_ENCRYPT(X.r, X.l, ctx->sched[0xe]);
279 F_ENCRYPT(X.l, X.r, ctx->sched[0xd]);
280 F_ENCRYPT(X.r, X.l, ctx->sched[0xc]);
281 F_ENCRYPT(X.l, X.r, ctx->sched[0xb]);
282 F_ENCRYPT(X.r, X.l, ctx->sched[0xa]);
283 F_ENCRYPT(X.l, X.r, ctx->sched[0x9]);
284 F_ENCRYPT(X.r, X.l, ctx->sched[0x8]);
285 F_ENCRYPT(X.l, X.r, ctx->sched[0x7]);
286 F_ENCRYPT(X.r, X.l, ctx->sched[0x6]);
287 F_ENCRYPT(X.l, X.r, ctx->sched[0x5]);
288 F_ENCRYPT(X.r, X.l, ctx->sched[0x4]);
289 F_ENCRYPT(X.l, X.r, ctx->sched[0x3]);
290 F_ENCRYPT(X.r, X.l, ctx->sched[0x2]);
291 F_ENCRYPT(X.l, X.r, ctx->sched[0x1]);
292 F_ENCRYPT(X.r, X.l, ctx->sched[0x0]);
293
294 memcpy(dst, &X, sizeof(X));
295 }
296
297 /*
298 * Generate a key schedule from key, the least significant bit in each key byte
299 * is parity and shall be ignored. This leaves 56 significant bits in the key
300 * to scatter over the 16 key schedules. For each schedule extract the low
301 * order 32 bits and use as schedule, then rotate right by 11 bits.
302 */
fcrypt_setkey(struct crypto_tfm * tfm,const u8 * key,unsigned int keylen)303 static int fcrypt_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
304 {
305 struct fcrypt_ctx *ctx = crypto_tfm_ctx(tfm);
306
307 #if BITS_PER_LONG == 64 /* the 64-bit version can also be used for 32-bit
308 * kernels - it seems to be faster but the code is
309 * larger */
310
311 u64 k; /* k holds all 56 non-parity bits */
312
313 /* discard the parity bits */
314 k = (*key++) >> 1;
315 k <<= 7;
316 k |= (*key++) >> 1;
317 k <<= 7;
318 k |= (*key++) >> 1;
319 k <<= 7;
320 k |= (*key++) >> 1;
321 k <<= 7;
322 k |= (*key++) >> 1;
323 k <<= 7;
324 k |= (*key++) >> 1;
325 k <<= 7;
326 k |= (*key++) >> 1;
327 k <<= 7;
328 k |= (*key) >> 1;
329
330 /* Use lower 32 bits for schedule, rotate by 11 each round (16 times) */
331 ctx->sched[0x0] = cpu_to_be32(k); ror56_64(k, 11);
332 ctx->sched[0x1] = cpu_to_be32(k); ror56_64(k, 11);
333 ctx->sched[0x2] = cpu_to_be32(k); ror56_64(k, 11);
334 ctx->sched[0x3] = cpu_to_be32(k); ror56_64(k, 11);
335 ctx->sched[0x4] = cpu_to_be32(k); ror56_64(k, 11);
336 ctx->sched[0x5] = cpu_to_be32(k); ror56_64(k, 11);
337 ctx->sched[0x6] = cpu_to_be32(k); ror56_64(k, 11);
338 ctx->sched[0x7] = cpu_to_be32(k); ror56_64(k, 11);
339 ctx->sched[0x8] = cpu_to_be32(k); ror56_64(k, 11);
340 ctx->sched[0x9] = cpu_to_be32(k); ror56_64(k, 11);
341 ctx->sched[0xa] = cpu_to_be32(k); ror56_64(k, 11);
342 ctx->sched[0xb] = cpu_to_be32(k); ror56_64(k, 11);
343 ctx->sched[0xc] = cpu_to_be32(k); ror56_64(k, 11);
344 ctx->sched[0xd] = cpu_to_be32(k); ror56_64(k, 11);
345 ctx->sched[0xe] = cpu_to_be32(k); ror56_64(k, 11);
346 ctx->sched[0xf] = cpu_to_be32(k);
347
348 return 0;
349 #else
350 u32 hi, lo; /* hi is upper 24 bits and lo lower 32, total 56 */
351
352 /* discard the parity bits */
353 lo = (*key++) >> 1;
354 lo <<= 7;
355 lo |= (*key++) >> 1;
356 lo <<= 7;
357 lo |= (*key++) >> 1;
358 lo <<= 7;
359 lo |= (*key++) >> 1;
360 hi = lo >> 4;
361 lo &= 0xf;
362 lo <<= 7;
363 lo |= (*key++) >> 1;
364 lo <<= 7;
365 lo |= (*key++) >> 1;
366 lo <<= 7;
367 lo |= (*key++) >> 1;
368 lo <<= 7;
369 lo |= (*key) >> 1;
370
371 /* Use lower 32 bits for schedule, rotate by 11 each round (16 times) */
372 ctx->sched[0x0] = cpu_to_be32(lo); ror56(hi, lo, 11);
373 ctx->sched[0x1] = cpu_to_be32(lo); ror56(hi, lo, 11);
374 ctx->sched[0x2] = cpu_to_be32(lo); ror56(hi, lo, 11);
375 ctx->sched[0x3] = cpu_to_be32(lo); ror56(hi, lo, 11);
376 ctx->sched[0x4] = cpu_to_be32(lo); ror56(hi, lo, 11);
377 ctx->sched[0x5] = cpu_to_be32(lo); ror56(hi, lo, 11);
378 ctx->sched[0x6] = cpu_to_be32(lo); ror56(hi, lo, 11);
379 ctx->sched[0x7] = cpu_to_be32(lo); ror56(hi, lo, 11);
380 ctx->sched[0x8] = cpu_to_be32(lo); ror56(hi, lo, 11);
381 ctx->sched[0x9] = cpu_to_be32(lo); ror56(hi, lo, 11);
382 ctx->sched[0xa] = cpu_to_be32(lo); ror56(hi, lo, 11);
383 ctx->sched[0xb] = cpu_to_be32(lo); ror56(hi, lo, 11);
384 ctx->sched[0xc] = cpu_to_be32(lo); ror56(hi, lo, 11);
385 ctx->sched[0xd] = cpu_to_be32(lo); ror56(hi, lo, 11);
386 ctx->sched[0xe] = cpu_to_be32(lo); ror56(hi, lo, 11);
387 ctx->sched[0xf] = cpu_to_be32(lo);
388 return 0;
389 #endif
390 }
391
392 static struct crypto_alg fcrypt_alg = {
393 .cra_name = "fcrypt",
394 .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
395 .cra_blocksize = 8,
396 .cra_ctxsize = sizeof(struct fcrypt_ctx),
397 .cra_module = THIS_MODULE,
398 .cra_alignmask = 3,
399 .cra_u = { .cipher = {
400 .cia_min_keysize = 8,
401 .cia_max_keysize = 8,
402 .cia_setkey = fcrypt_setkey,
403 .cia_encrypt = fcrypt_encrypt,
404 .cia_decrypt = fcrypt_decrypt } }
405 };
406
fcrypt_mod_init(void)407 static int __init fcrypt_mod_init(void)
408 {
409 return crypto_register_alg(&fcrypt_alg);
410 }
411
fcrypt_mod_fini(void)412 static void __exit fcrypt_mod_fini(void)
413 {
414 crypto_unregister_alg(&fcrypt_alg);
415 }
416
417 module_init(fcrypt_mod_init);
418 module_exit(fcrypt_mod_fini);
419
420 MODULE_LICENSE("Dual BSD/GPL");
421 MODULE_DESCRIPTION("FCrypt Cipher Algorithm");
422 MODULE_AUTHOR("David Howells <dhowells@redhat.com>");
423