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 <linux/bitops.h>
47#include <linux/init.h>
48#include <linux/module.h>
49#include <linux/crypto.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)						\
67do {								\
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)
77static 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 & 0x1f) << 27) | (x >> 5))
114static 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)
151static 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)
188static 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)						\
227do {									\
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 */
236static 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 */
268static 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 */
303static 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
392static 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
407static int __init fcrypt_mod_init(void)
408{
409	return crypto_register_alg(&fcrypt_alg);
410}
411
412static void __exit fcrypt_mod_fini(void)
413{
414	crypto_unregister_alg(&fcrypt_alg);
415}
416
417module_init(fcrypt_mod_init);
418module_exit(fcrypt_mod_fini);
419
420MODULE_LICENSE("Dual BSD/GPL");
421MODULE_DESCRIPTION("FCrypt Cipher Algorithm");
422MODULE_AUTHOR("David Howells <dhowells@redhat.com>");
423MODULE_ALIAS_CRYPTO("fcrypt");
424