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 H��gskolan
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 <crypto/algapi.h>
47#include <linux/bitops.h>
48#include <linux/init.h>
49#include <linux/module.h>
50
51#define ROUNDS 16
52
53struct 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)					\
59do {								\
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) (k = (k >> n) | ((k & ((1 << n) - 1)) << (56 - n)))
67
68/*
69 * Sboxes for Feistel network derived from
70 * /afs/transarc.com/public/afsps/afs.rel31b.export-src/rxkad/sboxes.h
71 */
72#undef Z
73#define Z(x) cpu_to_be32(x << 3)
74static const __be32 sbox0[256] = {
75	Z(0xea), Z(0x7f), Z(0xb2), Z(0x64), Z(0x9d), Z(0xb0), Z(0xd9), Z(0x11),
76	Z(0xcd), Z(0x86), Z(0x86), Z(0x91), Z(0x0a), Z(0xb2), Z(0x93), Z(0x06),
77	Z(0x0e), Z(0x06), Z(0xd2), Z(0x65), Z(0x73), Z(0xc5), Z(0x28), Z(0x60),
78	Z(0xf2), Z(0x20), Z(0xb5), Z(0x38), Z(0x7e), Z(0xda), Z(0x9f), Z(0xe3),
79	Z(0xd2), Z(0xcf), Z(0xc4), Z(0x3c), Z(0x61), Z(0xff), Z(0x4a), Z(0x4a),
80	Z(0x35), Z(0xac), Z(0xaa), Z(0x5f), Z(0x2b), Z(0xbb), Z(0xbc), Z(0x53),
81	Z(0x4e), Z(0x9d), Z(0x78), Z(0xa3), Z(0xdc), Z(0x09), Z(0x32), Z(0x10),
82	Z(0xc6), Z(0x6f), Z(0x66), Z(0xd6), Z(0xab), Z(0xa9), Z(0xaf), Z(0xfd),
83	Z(0x3b), Z(0x95), Z(0xe8), Z(0x34), Z(0x9a), Z(0x81), Z(0x72), Z(0x80),
84	Z(0x9c), Z(0xf3), Z(0xec), Z(0xda), Z(0x9f), Z(0x26), Z(0x76), Z(0x15),
85	Z(0x3e), Z(0x55), Z(0x4d), Z(0xde), Z(0x84), Z(0xee), Z(0xad), Z(0xc7),
86	Z(0xf1), Z(0x6b), Z(0x3d), Z(0xd3), Z(0x04), Z(0x49), Z(0xaa), Z(0x24),
87	Z(0x0b), Z(0x8a), Z(0x83), Z(0xba), Z(0xfa), Z(0x85), Z(0xa0), Z(0xa8),
88	Z(0xb1), Z(0xd4), Z(0x01), Z(0xd8), Z(0x70), Z(0x64), Z(0xf0), Z(0x51),
89	Z(0xd2), Z(0xc3), Z(0xa7), Z(0x75), Z(0x8c), Z(0xa5), Z(0x64), Z(0xef),
90	Z(0x10), Z(0x4e), Z(0xb7), Z(0xc6), Z(0x61), Z(0x03), Z(0xeb), Z(0x44),
91	Z(0x3d), Z(0xe5), Z(0xb3), Z(0x5b), Z(0xae), Z(0xd5), Z(0xad), Z(0x1d),
92	Z(0xfa), Z(0x5a), Z(0x1e), Z(0x33), Z(0xab), Z(0x93), Z(0xa2), Z(0xb7),
93	Z(0xe7), Z(0xa8), Z(0x45), Z(0xa4), Z(0xcd), Z(0x29), Z(0x63), Z(0x44),
94	Z(0xb6), Z(0x69), Z(0x7e), Z(0x2e), Z(0x62), Z(0x03), Z(0xc8), Z(0xe0),
95	Z(0x17), Z(0xbb), Z(0xc7), Z(0xf3), Z(0x3f), Z(0x36), Z(0xba), Z(0x71),
96	Z(0x8e), Z(0x97), Z(0x65), Z(0x60), Z(0x69), Z(0xb6), Z(0xf6), Z(0xe6),
97	Z(0x6e), Z(0xe0), Z(0x81), Z(0x59), Z(0xe8), Z(0xaf), Z(0xdd), Z(0x95),
98	Z(0x22), Z(0x99), Z(0xfd), Z(0x63), Z(0x19), Z(0x74), Z(0x61), Z(0xb1),
99	Z(0xb6), Z(0x5b), Z(0xae), Z(0x54), Z(0xb3), Z(0x70), Z(0xff), Z(0xc6),
100	Z(0x3b), Z(0x3e), Z(0xc1), Z(0xd7), Z(0xe1), Z(0x0e), Z(0x76), Z(0xe5),
101	Z(0x36), Z(0x4f), Z(0x59), Z(0xc7), Z(0x08), Z(0x6e), Z(0x82), Z(0xa6),
102	Z(0x93), Z(0xc4), Z(0xaa), Z(0x26), Z(0x49), Z(0xe0), Z(0x21), Z(0x64),
103	Z(0x07), Z(0x9f), Z(0x64), Z(0x81), Z(0x9c), Z(0xbf), Z(0xf9), Z(0xd1),
104	Z(0x43), Z(0xf8), Z(0xb6), Z(0xb9), Z(0xf1), Z(0x24), Z(0x75), Z(0x03),
105	Z(0xe4), Z(0xb0), Z(0x99), Z(0x46), Z(0x3d), Z(0xf5), Z(0xd1), Z(0x39),
106	Z(0x72), Z(0x12), Z(0xf6), Z(0xba), Z(0x0c), Z(0x0d), Z(0x42), Z(0x2e)
107};
108
109#undef Z
110#define Z(x) cpu_to_be32(((x & 0x1f) << 27) | (x >> 5))
111static const __be32 sbox1[256] = {
112	Z(0x77), Z(0x14), Z(0xa6), Z(0xfe), Z(0xb2), Z(0x5e), Z(0x8c), Z(0x3e),
113	Z(0x67), Z(0x6c), Z(0xa1), Z(0x0d), Z(0xc2), Z(0xa2), Z(0xc1), Z(0x85),
114	Z(0x6c), Z(0x7b), Z(0x67), Z(0xc6), Z(0x23), Z(0xe3), Z(0xf2), Z(0x89),
115	Z(0x50), Z(0x9c), Z(0x03), Z(0xb7), Z(0x73), Z(0xe6), Z(0xe1), Z(0x39),
116	Z(0x31), Z(0x2c), Z(0x27), Z(0x9f), Z(0xa5), Z(0x69), Z(0x44), Z(0xd6),
117	Z(0x23), Z(0x83), Z(0x98), Z(0x7d), Z(0x3c), Z(0xb4), Z(0x2d), Z(0x99),
118	Z(0x1c), Z(0x1f), Z(0x8c), Z(0x20), Z(0x03), Z(0x7c), Z(0x5f), Z(0xad),
119	Z(0xf4), Z(0xfa), Z(0x95), Z(0xca), Z(0x76), Z(0x44), Z(0xcd), Z(0xb6),
120	Z(0xb8), Z(0xa1), Z(0xa1), Z(0xbe), Z(0x9e), Z(0x54), Z(0x8f), Z(0x0b),
121	Z(0x16), Z(0x74), Z(0x31), Z(0x8a), Z(0x23), Z(0x17), Z(0x04), Z(0xfa),
122	Z(0x79), Z(0x84), Z(0xb1), Z(0xf5), Z(0x13), Z(0xab), Z(0xb5), Z(0x2e),
123	Z(0xaa), Z(0x0c), Z(0x60), Z(0x6b), Z(0x5b), Z(0xc4), Z(0x4b), Z(0xbc),
124	Z(0xe2), Z(0xaf), Z(0x45), Z(0x73), Z(0xfa), Z(0xc9), Z(0x49), Z(0xcd),
125	Z(0x00), Z(0x92), Z(0x7d), Z(0x97), Z(0x7a), Z(0x18), Z(0x60), Z(0x3d),
126	Z(0xcf), Z(0x5b), Z(0xde), Z(0xc6), Z(0xe2), Z(0xe6), Z(0xbb), Z(0x8b),
127	Z(0x06), Z(0xda), Z(0x08), Z(0x15), Z(0x1b), Z(0x88), Z(0x6a), Z(0x17),
128	Z(0x89), Z(0xd0), Z(0xa9), Z(0xc1), Z(0xc9), Z(0x70), Z(0x6b), Z(0xe5),
129	Z(0x43), Z(0xf4), Z(0x68), Z(0xc8), Z(0xd3), Z(0x84), Z(0x28), Z(0x0a),
130	Z(0x52), Z(0x66), Z(0xa3), Z(0xca), Z(0xf2), Z(0xe3), Z(0x7f), Z(0x7a),
131	Z(0x31), Z(0xf7), Z(0x88), Z(0x94), Z(0x5e), Z(0x9c), Z(0x63), Z(0xd5),
132	Z(0x24), Z(0x66), Z(0xfc), Z(0xb3), Z(0x57), Z(0x25), Z(0xbe), Z(0x89),
133	Z(0x44), Z(0xc4), Z(0xe0), Z(0x8f), Z(0x23), Z(0x3c), Z(0x12), Z(0x52),
134	Z(0xf5), Z(0x1e), Z(0xf4), Z(0xcb), Z(0x18), Z(0x33), Z(0x1f), Z(0xf8),
135	Z(0x69), Z(0x10), Z(0x9d), Z(0xd3), Z(0xf7), Z(0x28), Z(0xf8), Z(0x30),
136	Z(0x05), Z(0x5e), Z(0x32), Z(0xc0), Z(0xd5), Z(0x19), Z(0xbd), Z(0x45),
137	Z(0x8b), Z(0x5b), Z(0xfd), Z(0xbc), Z(0xe2), Z(0x5c), Z(0xa9), Z(0x96),
138	Z(0xef), Z(0x70), Z(0xcf), Z(0xc2), Z(0x2a), Z(0xb3), Z(0x61), Z(0xad),
139	Z(0x80), Z(0x48), Z(0x81), Z(0xb7), Z(0x1d), Z(0x43), Z(0xd9), Z(0xd7),
140	Z(0x45), Z(0xf0), Z(0xd8), Z(0x8a), Z(0x59), Z(0x7c), Z(0x57), Z(0xc1),
141	Z(0x79), Z(0xc7), Z(0x34), Z(0xd6), Z(0x43), Z(0xdf), Z(0xe4), Z(0x78),
142	Z(0x16), Z(0x06), Z(0xda), Z(0x92), Z(0x76), Z(0x51), Z(0xe1), Z(0xd4),
143	Z(0x70), Z(0x03), Z(0xe0), Z(0x2f), Z(0x96), Z(0x91), Z(0x82), Z(0x80)
144};
145
146#undef Z
147#define Z(x) cpu_to_be32(x << 11)
148static const __be32 sbox2[256] = {
149	Z(0xf0), Z(0x37), Z(0x24), Z(0x53), Z(0x2a), Z(0x03), Z(0x83), Z(0x86),
150	Z(0xd1), Z(0xec), Z(0x50), Z(0xf0), Z(0x42), Z(0x78), Z(0x2f), Z(0x6d),
151	Z(0xbf), Z(0x80), Z(0x87), Z(0x27), Z(0x95), Z(0xe2), Z(0xc5), Z(0x5d),
152	Z(0xf9), Z(0x6f), Z(0xdb), Z(0xb4), Z(0x65), Z(0x6e), Z(0xe7), Z(0x24),
153	Z(0xc8), Z(0x1a), Z(0xbb), Z(0x49), Z(0xb5), Z(0x0a), Z(0x7d), Z(0xb9),
154	Z(0xe8), Z(0xdc), Z(0xb7), Z(0xd9), Z(0x45), Z(0x20), Z(0x1b), Z(0xce),
155	Z(0x59), Z(0x9d), Z(0x6b), Z(0xbd), Z(0x0e), Z(0x8f), Z(0xa3), Z(0xa9),
156	Z(0xbc), Z(0x74), Z(0xa6), Z(0xf6), Z(0x7f), Z(0x5f), Z(0xb1), Z(0x68),
157	Z(0x84), Z(0xbc), Z(0xa9), Z(0xfd), Z(0x55), Z(0x50), Z(0xe9), Z(0xb6),
158	Z(0x13), Z(0x5e), Z(0x07), Z(0xb8), Z(0x95), Z(0x02), Z(0xc0), Z(0xd0),
159	Z(0x6a), Z(0x1a), Z(0x85), Z(0xbd), Z(0xb6), Z(0xfd), Z(0xfe), Z(0x17),
160	Z(0x3f), Z(0x09), Z(0xa3), Z(0x8d), Z(0xfb), Z(0xed), Z(0xda), Z(0x1d),
161	Z(0x6d), Z(0x1c), Z(0x6c), Z(0x01), Z(0x5a), Z(0xe5), Z(0x71), Z(0x3e),
162	Z(0x8b), Z(0x6b), Z(0xbe), Z(0x29), Z(0xeb), Z(0x12), Z(0x19), Z(0x34),
163	Z(0xcd), Z(0xb3), Z(0xbd), Z(0x35), Z(0xea), Z(0x4b), Z(0xd5), Z(0xae),
164	Z(0x2a), Z(0x79), Z(0x5a), Z(0xa5), Z(0x32), Z(0x12), Z(0x7b), Z(0xdc),
165	Z(0x2c), Z(0xd0), Z(0x22), Z(0x4b), Z(0xb1), Z(0x85), Z(0x59), Z(0x80),
166	Z(0xc0), Z(0x30), Z(0x9f), Z(0x73), Z(0xd3), Z(0x14), Z(0x48), Z(0x40),
167	Z(0x07), Z(0x2d), Z(0x8f), Z(0x80), Z(0x0f), Z(0xce), Z(0x0b), Z(0x5e),
168	Z(0xb7), Z(0x5e), Z(0xac), Z(0x24), Z(0x94), Z(0x4a), Z(0x18), Z(0x15),
169	Z(0x05), Z(0xe8), Z(0x02), Z(0x77), Z(0xa9), Z(0xc7), Z(0x40), Z(0x45),
170	Z(0x89), Z(0xd1), Z(0xea), Z(0xde), Z(0x0c), Z(0x79), Z(0x2a), Z(0x99),
171	Z(0x6c), Z(0x3e), Z(0x95), Z(0xdd), Z(0x8c), Z(0x7d), Z(0xad), Z(0x6f),
172	Z(0xdc), Z(0xff), Z(0xfd), Z(0x62), Z(0x47), Z(0xb3), Z(0x21), Z(0x8a),
173	Z(0xec), Z(0x8e), Z(0x19), Z(0x18), Z(0xb4), Z(0x6e), Z(0x3d), Z(0xfd),
174	Z(0x74), Z(0x54), Z(0x1e), Z(0x04), Z(0x85), Z(0xd8), Z(0xbc), Z(0x1f),
175	Z(0x56), Z(0xe7), Z(0x3a), Z(0x56), Z(0x67), Z(0xd6), Z(0xc8), Z(0xa5),
176	Z(0xf3), Z(0x8e), Z(0xde), Z(0xae), Z(0x37), Z(0x49), Z(0xb7), Z(0xfa),
177	Z(0xc8), Z(0xf4), Z(0x1f), Z(0xe0), Z(0x2a), Z(0x9b), Z(0x15), Z(0xd1),
178	Z(0x34), Z(0x0e), Z(0xb5), Z(0xe0), Z(0x44), Z(0x78), Z(0x84), Z(0x59),
179	Z(0x56), Z(0x68), Z(0x77), Z(0xa5), Z(0x14), Z(0x06), Z(0xf5), Z(0x2f),
180	Z(0x8c), Z(0x8a), Z(0x73), Z(0x80), Z(0x76), Z(0xb4), Z(0x10), Z(0x86)
181};
182
183#undef Z
184#define Z(x) cpu_to_be32(x << 19)
185static const __be32 sbox3[256] = {
186	Z(0xa9), Z(0x2a), Z(0x48), Z(0x51), Z(0x84), Z(0x7e), Z(0x49), Z(0xe2),
187	Z(0xb5), Z(0xb7), Z(0x42), Z(0x33), Z(0x7d), Z(0x5d), Z(0xa6), Z(0x12),
188	Z(0x44), Z(0x48), Z(0x6d), Z(0x28), Z(0xaa), Z(0x20), Z(0x6d), Z(0x57),
189	Z(0xd6), Z(0x6b), Z(0x5d), Z(0x72), Z(0xf0), Z(0x92), Z(0x5a), Z(0x1b),
190	Z(0x53), Z(0x80), Z(0x24), Z(0x70), Z(0x9a), Z(0xcc), Z(0xa7), Z(0x66),
191	Z(0xa1), Z(0x01), Z(0xa5), Z(0x41), Z(0x97), Z(0x41), Z(0x31), Z(0x82),
192	Z(0xf1), Z(0x14), Z(0xcf), Z(0x53), Z(0x0d), Z(0xa0), Z(0x10), Z(0xcc),
193	Z(0x2a), Z(0x7d), Z(0xd2), Z(0xbf), Z(0x4b), Z(0x1a), Z(0xdb), Z(0x16),
194	Z(0x47), Z(0xf6), Z(0x51), Z(0x36), Z(0xed), Z(0xf3), Z(0xb9), Z(0x1a),
195	Z(0xa7), Z(0xdf), Z(0x29), Z(0x43), Z(0x01), Z(0x54), Z(0x70), Z(0xa4),
196	Z(0xbf), Z(0xd4), Z(0x0b), Z(0x53), Z(0x44), Z(0x60), Z(0x9e), Z(0x23),
197	Z(0xa1), Z(0x18), Z(0x68), Z(0x4f), Z(0xf0), Z(0x2f), Z(0x82), Z(0xc2),
198	Z(0x2a), Z(0x41), Z(0xb2), Z(0x42), Z(0x0c), Z(0xed), Z(0x0c), Z(0x1d),
199	Z(0x13), Z(0x3a), Z(0x3c), Z(0x6e), Z(0x35), Z(0xdc), Z(0x60), Z(0x65),
200	Z(0x85), Z(0xe9), Z(0x64), Z(0x02), Z(0x9a), Z(0x3f), Z(0x9f), Z(0x87),
201	Z(0x96), Z(0xdf), Z(0xbe), Z(0xf2), Z(0xcb), Z(0xe5), Z(0x6c), Z(0xd4),
202	Z(0x5a), Z(0x83), Z(0xbf), Z(0x92), Z(0x1b), Z(0x94), Z(0x00), Z(0x42),
203	Z(0xcf), Z(0x4b), Z(0x00), Z(0x75), Z(0xba), Z(0x8f), Z(0x76), Z(0x5f),
204	Z(0x5d), Z(0x3a), Z(0x4d), Z(0x09), Z(0x12), Z(0x08), Z(0x38), Z(0x95),
205	Z(0x17), Z(0xe4), Z(0x01), Z(0x1d), Z(0x4c), Z(0xa9), Z(0xcc), Z(0x85),
206	Z(0x82), Z(0x4c), Z(0x9d), Z(0x2f), Z(0x3b), Z(0x66), Z(0xa1), Z(0x34),
207	Z(0x10), Z(0xcd), Z(0x59), Z(0x89), Z(0xa5), Z(0x31), Z(0xcf), Z(0x05),
208	Z(0xc8), Z(0x84), Z(0xfa), Z(0xc7), Z(0xba), Z(0x4e), Z(0x8b), Z(0x1a),
209	Z(0x19), Z(0xf1), Z(0xa1), Z(0x3b), Z(0x18), Z(0x12), Z(0x17), Z(0xb0),
210	Z(0x98), Z(0x8d), Z(0x0b), Z(0x23), Z(0xc3), Z(0x3a), Z(0x2d), Z(0x20),
211	Z(0xdf), Z(0x13), Z(0xa0), Z(0xa8), Z(0x4c), Z(0x0d), Z(0x6c), Z(0x2f),
212	Z(0x47), Z(0x13), Z(0x13), Z(0x52), Z(0x1f), Z(0x2d), Z(0xf5), Z(0x79),
213	Z(0x3d), Z(0xa2), Z(0x54), Z(0xbd), Z(0x69), Z(0xc8), Z(0x6b), Z(0xf3),
214	Z(0x05), Z(0x28), Z(0xf1), Z(0x16), Z(0x46), Z(0x40), Z(0xb0), Z(0x11),
215	Z(0xd3), Z(0xb7), Z(0x95), Z(0x49), Z(0xcf), Z(0xc3), Z(0x1d), Z(0x8f),
216	Z(0xd8), Z(0xe1), Z(0x73), Z(0xdb), Z(0xad), Z(0xc8), Z(0xc9), Z(0xa9),
217	Z(0xa1), Z(0xc2), Z(0xc5), Z(0xe3), Z(0xba), Z(0xfc), Z(0x0e), Z(0x25)
218};
219
220/*
221 * This is a 16 round Feistel network with permutation F_ENCRYPT
222 */
223#define F_ENCRYPT(R, L, sched)						\
224do {									\
225	union lc4 { __be32 l; u8 c[4]; } u;				\
226	u.l = sched ^ R;						\
227	L ^= sbox0[u.c[0]] ^ sbox1[u.c[1]] ^ sbox2[u.c[2]] ^ sbox3[u.c[3]]; \
228} while (0)
229
230/*
231 * encryptor
232 */
233static void fcrypt_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
234{
235	const struct fcrypt_ctx *ctx = crypto_tfm_ctx(tfm);
236	struct {
237		__be32 l, r;
238	} X;
239
240	memcpy(&X, src, sizeof(X));
241
242	F_ENCRYPT(X.r, X.l, ctx->sched[0x0]);
243	F_ENCRYPT(X.l, X.r, ctx->sched[0x1]);
244	F_ENCRYPT(X.r, X.l, ctx->sched[0x2]);
245	F_ENCRYPT(X.l, X.r, ctx->sched[0x3]);
246	F_ENCRYPT(X.r, X.l, ctx->sched[0x4]);
247	F_ENCRYPT(X.l, X.r, ctx->sched[0x5]);
248	F_ENCRYPT(X.r, X.l, ctx->sched[0x6]);
249	F_ENCRYPT(X.l, X.r, ctx->sched[0x7]);
250	F_ENCRYPT(X.r, X.l, ctx->sched[0x8]);
251	F_ENCRYPT(X.l, X.r, ctx->sched[0x9]);
252	F_ENCRYPT(X.r, X.l, ctx->sched[0xa]);
253	F_ENCRYPT(X.l, X.r, ctx->sched[0xb]);
254	F_ENCRYPT(X.r, X.l, ctx->sched[0xc]);
255	F_ENCRYPT(X.l, X.r, ctx->sched[0xd]);
256	F_ENCRYPT(X.r, X.l, ctx->sched[0xe]);
257	F_ENCRYPT(X.l, X.r, ctx->sched[0xf]);
258
259	memcpy(dst, &X, sizeof(X));
260}
261
262/*
263 * decryptor
264 */
265static void fcrypt_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
266{
267	const struct fcrypt_ctx *ctx = crypto_tfm_ctx(tfm);
268	struct {
269		__be32 l, r;
270	} X;
271
272	memcpy(&X, src, sizeof(X));
273
274	F_ENCRYPT(X.l, X.r, ctx->sched[0xf]);
275	F_ENCRYPT(X.r, X.l, ctx->sched[0xe]);
276	F_ENCRYPT(X.l, X.r, ctx->sched[0xd]);
277	F_ENCRYPT(X.r, X.l, ctx->sched[0xc]);
278	F_ENCRYPT(X.l, X.r, ctx->sched[0xb]);
279	F_ENCRYPT(X.r, X.l, ctx->sched[0xa]);
280	F_ENCRYPT(X.l, X.r, ctx->sched[0x9]);
281	F_ENCRYPT(X.r, X.l, ctx->sched[0x8]);
282	F_ENCRYPT(X.l, X.r, ctx->sched[0x7]);
283	F_ENCRYPT(X.r, X.l, ctx->sched[0x6]);
284	F_ENCRYPT(X.l, X.r, ctx->sched[0x5]);
285	F_ENCRYPT(X.r, X.l, ctx->sched[0x4]);
286	F_ENCRYPT(X.l, X.r, ctx->sched[0x3]);
287	F_ENCRYPT(X.r, X.l, ctx->sched[0x2]);
288	F_ENCRYPT(X.l, X.r, ctx->sched[0x1]);
289	F_ENCRYPT(X.r, X.l, ctx->sched[0x0]);
290
291	memcpy(dst, &X, sizeof(X));
292}
293
294/*
295 * Generate a key schedule from key, the least significant bit in each key byte
296 * is parity and shall be ignored. This leaves 56 significant bits in the key
297 * to scatter over the 16 key schedules. For each schedule extract the low
298 * order 32 bits and use as schedule, then rotate right by 11 bits.
299 */
300static int fcrypt_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
301{
302	struct fcrypt_ctx *ctx = crypto_tfm_ctx(tfm);
303
304#if BITS_PER_LONG == 64  /* the 64-bit version can also be used for 32-bit
305			  * kernels - it seems to be faster but the code is
306			  * larger */
307
308	u64 k;	/* k holds all 56 non-parity bits */
309
310	/* discard the parity bits */
311	k = (*key++) >> 1;
312	k <<= 7;
313	k |= (*key++) >> 1;
314	k <<= 7;
315	k |= (*key++) >> 1;
316	k <<= 7;
317	k |= (*key++) >> 1;
318	k <<= 7;
319	k |= (*key++) >> 1;
320	k <<= 7;
321	k |= (*key++) >> 1;
322	k <<= 7;
323	k |= (*key++) >> 1;
324	k <<= 7;
325	k |= (*key) >> 1;
326
327	/* Use lower 32 bits for schedule, rotate by 11 each round (16 times) */
328	ctx->sched[0x0] = cpu_to_be32(k); ror56_64(k, 11);
329	ctx->sched[0x1] = cpu_to_be32(k); ror56_64(k, 11);
330	ctx->sched[0x2] = cpu_to_be32(k); ror56_64(k, 11);
331	ctx->sched[0x3] = cpu_to_be32(k); ror56_64(k, 11);
332	ctx->sched[0x4] = cpu_to_be32(k); ror56_64(k, 11);
333	ctx->sched[0x5] = cpu_to_be32(k); ror56_64(k, 11);
334	ctx->sched[0x6] = cpu_to_be32(k); ror56_64(k, 11);
335	ctx->sched[0x7] = cpu_to_be32(k); ror56_64(k, 11);
336	ctx->sched[0x8] = cpu_to_be32(k); ror56_64(k, 11);
337	ctx->sched[0x9] = cpu_to_be32(k); ror56_64(k, 11);
338	ctx->sched[0xa] = cpu_to_be32(k); ror56_64(k, 11);
339	ctx->sched[0xb] = cpu_to_be32(k); ror56_64(k, 11);
340	ctx->sched[0xc] = cpu_to_be32(k); ror56_64(k, 11);
341	ctx->sched[0xd] = cpu_to_be32(k); ror56_64(k, 11);
342	ctx->sched[0xe] = cpu_to_be32(k); ror56_64(k, 11);
343	ctx->sched[0xf] = cpu_to_be32(k);
344
345	return 0;
346#else
347	u32 hi, lo;		/* hi is upper 24 bits and lo lower 32, total 56 */
348
349	/* discard the parity bits */
350	lo = (*key++) >> 1;
351	lo <<= 7;
352	lo |= (*key++) >> 1;
353	lo <<= 7;
354	lo |= (*key++) >> 1;
355	lo <<= 7;
356	lo |= (*key++) >> 1;
357	hi = lo >> 4;
358	lo &= 0xf;
359	lo <<= 7;
360	lo |= (*key++) >> 1;
361	lo <<= 7;
362	lo |= (*key++) >> 1;
363	lo <<= 7;
364	lo |= (*key++) >> 1;
365	lo <<= 7;
366	lo |= (*key) >> 1;
367
368	/* Use lower 32 bits for schedule, rotate by 11 each round (16 times) */
369	ctx->sched[0x0] = cpu_to_be32(lo); ror56(hi, lo, 11);
370	ctx->sched[0x1] = cpu_to_be32(lo); ror56(hi, lo, 11);
371	ctx->sched[0x2] = cpu_to_be32(lo); ror56(hi, lo, 11);
372	ctx->sched[0x3] = cpu_to_be32(lo); ror56(hi, lo, 11);
373	ctx->sched[0x4] = cpu_to_be32(lo); ror56(hi, lo, 11);
374	ctx->sched[0x5] = cpu_to_be32(lo); ror56(hi, lo, 11);
375	ctx->sched[0x6] = cpu_to_be32(lo); ror56(hi, lo, 11);
376	ctx->sched[0x7] = cpu_to_be32(lo); ror56(hi, lo, 11);
377	ctx->sched[0x8] = cpu_to_be32(lo); ror56(hi, lo, 11);
378	ctx->sched[0x9] = cpu_to_be32(lo); ror56(hi, lo, 11);
379	ctx->sched[0xa] = cpu_to_be32(lo); ror56(hi, lo, 11);
380	ctx->sched[0xb] = cpu_to_be32(lo); ror56(hi, lo, 11);
381	ctx->sched[0xc] = cpu_to_be32(lo); ror56(hi, lo, 11);
382	ctx->sched[0xd] = cpu_to_be32(lo); ror56(hi, lo, 11);
383	ctx->sched[0xe] = cpu_to_be32(lo); ror56(hi, lo, 11);
384	ctx->sched[0xf] = cpu_to_be32(lo);
385	return 0;
386#endif
387}
388
389static struct crypto_alg fcrypt_alg = {
390	.cra_name		=	"fcrypt",
391	.cra_driver_name	=	"fcrypt-generic",
392	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
393	.cra_blocksize		=	8,
394	.cra_ctxsize		=	sizeof(struct fcrypt_ctx),
395	.cra_module		=	THIS_MODULE,
396	.cra_u			=	{ .cipher = {
397	.cia_min_keysize	=	8,
398	.cia_max_keysize	=	8,
399	.cia_setkey		=	fcrypt_setkey,
400	.cia_encrypt		=	fcrypt_encrypt,
401	.cia_decrypt		=	fcrypt_decrypt } }
402};
403
404static int __init fcrypt_mod_init(void)
405{
406	return crypto_register_alg(&fcrypt_alg);
407}
408
409static void __exit fcrypt_mod_fini(void)
410{
411	crypto_unregister_alg(&fcrypt_alg);
412}
413
414subsys_initcall(fcrypt_mod_init);
415module_exit(fcrypt_mod_fini);
416
417MODULE_LICENSE("Dual BSD/GPL");
418MODULE_DESCRIPTION("FCrypt Cipher Algorithm");
419MODULE_AUTHOR("David Howells <dhowells@redhat.com>");
420MODULE_ALIAS_CRYPTO("fcrypt");
421