xref: /linux/crypto/serpent_generic.c (revision 0d3b051adbb72ed81956447d0d1e54d5943ee6f5)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Cryptographic API.
4  *
5  * Serpent Cipher Algorithm.
6  *
7  * Copyright (C) 2002 Dag Arne Osvik <osvik@ii.uib.no>
8  *               2003 Herbert Valerio Riedel <hvr@gnu.org>
9  *
10  * Added tnepres support:
11  *		Ruben Jesus Garcia Hernandez <ruben@ugr.es>, 18.10.2004
12  *              Based on code by hvr
13  */
14 
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/errno.h>
18 #include <asm/byteorder.h>
19 #include <linux/crypto.h>
20 #include <linux/types.h>
21 #include <crypto/serpent.h>
22 
23 /* Key is padded to the maximum of 256 bits before round key generation.
24  * Any key length <= 256 bits (32 bytes) is allowed by the algorithm.
25  */
26 
27 #define PHI 0x9e3779b9UL
28 
29 #define keyiter(a, b, c, d, i, j) \
30 	({ b ^= d; b ^= c; b ^= a; b ^= PHI ^ i; b = rol32(b, 11); k[j] = b; })
31 
32 #define loadkeys(x0, x1, x2, x3, i) \
33 	({ x0 = k[i]; x1 = k[i+1]; x2 = k[i+2]; x3 = k[i+3]; })
34 
35 #define storekeys(x0, x1, x2, x3, i) \
36 	({ k[i] = x0; k[i+1] = x1; k[i+2] = x2; k[i+3] = x3; })
37 
38 #define store_and_load_keys(x0, x1, x2, x3, s, l) \
39 	({ storekeys(x0, x1, x2, x3, s); loadkeys(x0, x1, x2, x3, l); })
40 
41 #define K(x0, x1, x2, x3, i) ({				\
42 	x3 ^= k[4*(i)+3];        x2 ^= k[4*(i)+2];	\
43 	x1 ^= k[4*(i)+1];        x0 ^= k[4*(i)+0];	\
44 	})
45 
46 #define LK(x0, x1, x2, x3, x4, i) ({					   \
47 							x0 = rol32(x0, 13);\
48 	x2 = rol32(x2, 3);	x1 ^= x0;		x4  = x0 << 3;	   \
49 	x3 ^= x2;		x1 ^= x2;				   \
50 	x1 = rol32(x1, 1);	x3 ^= x4;				   \
51 	x3 = rol32(x3, 7);	x4  = x1;				   \
52 	x0 ^= x1;		x4 <<= 7;		x2 ^= x3;	   \
53 	x0 ^= x3;		x2 ^= x4;		x3 ^= k[4*i+3];	   \
54 	x1 ^= k[4*i+1];		x0 = rol32(x0, 5);	x2 = rol32(x2, 22);\
55 	x0 ^= k[4*i+0];		x2 ^= k[4*i+2];				   \
56 	})
57 
58 #define KL(x0, x1, x2, x3, x4, i) ({					   \
59 	x0 ^= k[4*i+0];		x1 ^= k[4*i+1];		x2 ^= k[4*i+2];	   \
60 	x3 ^= k[4*i+3];		x0 = ror32(x0, 5);	x2 = ror32(x2, 22);\
61 	x4 =  x1;		x2 ^= x3;		x0 ^= x3;	   \
62 	x4 <<= 7;		x0 ^= x1;		x1 = ror32(x1, 1); \
63 	x2 ^= x4;		x3 = ror32(x3, 7);	x4 = x0 << 3;	   \
64 	x1 ^= x0;		x3 ^= x4;		x0 = ror32(x0, 13);\
65 	x1 ^= x2;		x3 ^= x2;		x2 = ror32(x2, 3); \
66 	})
67 
68 #define S0(x0, x1, x2, x3, x4) ({			\
69 					x4  = x3;	\
70 	x3 |= x0;	x0 ^= x4;	x4 ^= x2;	\
71 	x4 = ~x4;	x3 ^= x1;	x1 &= x0;	\
72 	x1 ^= x4;	x2 ^= x0;	x0 ^= x3;	\
73 	x4 |= x0;	x0 ^= x2;	x2 &= x1;	\
74 	x3 ^= x2;	x1 = ~x1;	x2 ^= x4;	\
75 	x1 ^= x2;					\
76 	})
77 
78 #define S1(x0, x1, x2, x3, x4) ({			\
79 					x4  = x1;	\
80 	x1 ^= x0;	x0 ^= x3;	x3 = ~x3;	\
81 	x4 &= x1;	x0 |= x1;	x3 ^= x2;	\
82 	x0 ^= x3;	x1 ^= x3;	x3 ^= x4;	\
83 	x1 |= x4;	x4 ^= x2;	x2 &= x0;	\
84 	x2 ^= x1;	x1 |= x0;	x0 = ~x0;	\
85 	x0 ^= x2;	x4 ^= x1;			\
86 	})
87 
88 #define S2(x0, x1, x2, x3, x4) ({			\
89 					x3 = ~x3;	\
90 	x1 ^= x0;	x4  = x0;	x0 &= x2;	\
91 	x0 ^= x3;	x3 |= x4;	x2 ^= x1;	\
92 	x3 ^= x1;	x1 &= x0;	x0 ^= x2;	\
93 	x2 &= x3;	x3 |= x1;	x0 = ~x0;	\
94 	x3 ^= x0;	x4 ^= x0;	x0 ^= x2;	\
95 	x1 |= x2;					\
96 	})
97 
98 #define S3(x0, x1, x2, x3, x4) ({			\
99 					x4  = x1;	\
100 	x1 ^= x3;	x3 |= x0;	x4 &= x0;	\
101 	x0 ^= x2;	x2 ^= x1;	x1 &= x3;	\
102 	x2 ^= x3;	x0 |= x4;	x4 ^= x3;	\
103 	x1 ^= x0;	x0 &= x3;	x3 &= x4;	\
104 	x3 ^= x2;	x4 |= x1;	x2 &= x1;	\
105 	x4 ^= x3;	x0 ^= x3;	x3 ^= x2;	\
106 	})
107 
108 #define S4(x0, x1, x2, x3, x4) ({			\
109 					x4  = x3;	\
110 	x3 &= x0;	x0 ^= x4;			\
111 	x3 ^= x2;	x2 |= x4;	x0 ^= x1;	\
112 	x4 ^= x3;	x2 |= x0;			\
113 	x2 ^= x1;	x1 &= x0;			\
114 	x1 ^= x4;	x4 &= x2;	x2 ^= x3;	\
115 	x4 ^= x0;	x3 |= x1;	x1 = ~x1;	\
116 	x3 ^= x0;					\
117 	})
118 
119 #define S5(x0, x1, x2, x3, x4) ({			\
120 	x4  = x1;	x1 |= x0;			\
121 	x2 ^= x1;	x3 = ~x3;	x4 ^= x0;	\
122 	x0 ^= x2;	x1 &= x4;	x4 |= x3;	\
123 	x4 ^= x0;	x0 &= x3;	x1 ^= x3;	\
124 	x3 ^= x2;	x0 ^= x1;	x2 &= x4;	\
125 	x1 ^= x2;	x2 &= x0;			\
126 	x3 ^= x2;					\
127 	})
128 
129 #define S6(x0, x1, x2, x3, x4) ({			\
130 					x4  = x1;	\
131 	x3 ^= x0;	x1 ^= x2;	x2 ^= x0;	\
132 	x0 &= x3;	x1 |= x3;	x4 = ~x4;	\
133 	x0 ^= x1;	x1 ^= x2;			\
134 	x3 ^= x4;	x4 ^= x0;	x2 &= x0;	\
135 	x4 ^= x1;	x2 ^= x3;	x3 &= x1;	\
136 	x3 ^= x0;	x1 ^= x2;			\
137 	})
138 
139 #define S7(x0, x1, x2, x3, x4) ({			\
140 					x1 = ~x1;	\
141 	x4  = x1;	x0 = ~x0;	x1 &= x2;	\
142 	x1 ^= x3;	x3 |= x4;	x4 ^= x2;	\
143 	x2 ^= x3;	x3 ^= x0;	x0 |= x1;	\
144 	x2 &= x0;	x0 ^= x4;	x4 ^= x3;	\
145 	x3 &= x0;	x4 ^= x1;			\
146 	x2 ^= x4;	x3 ^= x1;	x4 |= x0;	\
147 	x4 ^= x1;					\
148 	})
149 
150 #define SI0(x0, x1, x2, x3, x4) ({			\
151 			x4  = x3;	x1 ^= x0;	\
152 	x3 |= x1;	x4 ^= x1;	x0 = ~x0;	\
153 	x2 ^= x3;	x3 ^= x0;	x0 &= x1;	\
154 	x0 ^= x2;	x2 &= x3;	x3 ^= x4;	\
155 	x2 ^= x3;	x1 ^= x3;	x3 &= x0;	\
156 	x1 ^= x0;	x0 ^= x2;	x4 ^= x3;	\
157 	})
158 
159 #define SI1(x0, x1, x2, x3, x4) ({			\
160 	x1 ^= x3;	x4  = x0;			\
161 	x0 ^= x2;	x2 = ~x2;	x4 |= x1;	\
162 	x4 ^= x3;	x3 &= x1;	x1 ^= x2;	\
163 	x2 &= x4;	x4 ^= x1;	x1 |= x3;	\
164 	x3 ^= x0;	x2 ^= x0;	x0 |= x4;	\
165 	x2 ^= x4;	x1 ^= x0;			\
166 	x4 ^= x1;					\
167 	})
168 
169 #define SI2(x0, x1, x2, x3, x4) ({			\
170 	x2 ^= x1;	x4  = x3;	x3 = ~x3;	\
171 	x3 |= x2;	x2 ^= x4;	x4 ^= x0;	\
172 	x3 ^= x1;	x1 |= x2;	x2 ^= x0;	\
173 	x1 ^= x4;	x4 |= x3;	x2 ^= x3;	\
174 	x4 ^= x2;	x2 &= x1;			\
175 	x2 ^= x3;	x3 ^= x4;	x4 ^= x0;	\
176 	})
177 
178 #define SI3(x0, x1, x2, x3, x4) ({			\
179 					x2 ^= x1;	\
180 	x4  = x1;	x1 &= x2;			\
181 	x1 ^= x0;	x0 |= x4;	x4 ^= x3;	\
182 	x0 ^= x3;	x3 |= x1;	x1 ^= x2;	\
183 	x1 ^= x3;	x0 ^= x2;	x2 ^= x3;	\
184 	x3 &= x1;	x1 ^= x0;	x0 &= x2;	\
185 	x4 ^= x3;	x3 ^= x0;	x0 ^= x1;	\
186 	})
187 
188 #define SI4(x0, x1, x2, x3, x4) ({			\
189 	x2 ^= x3;	x4  = x0;	x0 &= x1;	\
190 	x0 ^= x2;	x2 |= x3;	x4 = ~x4;	\
191 	x1 ^= x0;	x0 ^= x2;	x2 &= x4;	\
192 	x2 ^= x0;	x0 |= x4;			\
193 	x0 ^= x3;	x3 &= x2;			\
194 	x4 ^= x3;	x3 ^= x1;	x1 &= x0;	\
195 	x4 ^= x1;	x0 ^= x3;			\
196 	})
197 
198 #define SI5(x0, x1, x2, x3, x4) ({			\
199 			x4  = x1;	x1 |= x2;	\
200 	x2 ^= x4;	x1 ^= x3;	x3 &= x4;	\
201 	x2 ^= x3;	x3 |= x0;	x0 = ~x0;	\
202 	x3 ^= x2;	x2 |= x0;	x4 ^= x1;	\
203 	x2 ^= x4;	x4 &= x0;	x0 ^= x1;	\
204 	x1 ^= x3;	x0 &= x2;	x2 ^= x3;	\
205 	x0 ^= x2;	x2 ^= x4;	x4 ^= x3;	\
206 	})
207 
208 #define SI6(x0, x1, x2, x3, x4) ({			\
209 			x0 ^= x2;			\
210 	x4  = x0;	x0 &= x3;	x2 ^= x3;	\
211 	x0 ^= x2;	x3 ^= x1;	x2 |= x4;	\
212 	x2 ^= x3;	x3 &= x0;	x0 = ~x0;	\
213 	x3 ^= x1;	x1 &= x2;	x4 ^= x0;	\
214 	x3 ^= x4;	x4 ^= x2;	x0 ^= x1;	\
215 	x2 ^= x0;					\
216 	})
217 
218 #define SI7(x0, x1, x2, x3, x4) ({			\
219 	x4  = x3;	x3 &= x0;	x0 ^= x2;	\
220 	x2 |= x4;	x4 ^= x1;	x0 = ~x0;	\
221 	x1 |= x3;	x4 ^= x0;	x0 &= x2;	\
222 	x0 ^= x1;	x1 &= x2;	x3 ^= x2;	\
223 	x4 ^= x3;	x2 &= x3;	x3 |= x0;	\
224 	x1 ^= x4;	x3 ^= x4;	x4 &= x0;	\
225 	x4 ^= x2;					\
226 	})
227 
228 /*
229  * both gcc and clang have misoptimized this function in the past,
230  * producing horrible object code from spilling temporary variables
231  * on the stack. Forcing this part out of line avoids that.
232  */
233 static noinline void __serpent_setkey_sbox(u32 r0, u32 r1, u32 r2,
234 					   u32 r3, u32 r4, u32 *k)
235 {
236 	k += 100;
237 	S3(r3, r4, r0, r1, r2); store_and_load_keys(r1, r2, r4, r3, 28, 24);
238 	S4(r1, r2, r4, r3, r0); store_and_load_keys(r2, r4, r3, r0, 24, 20);
239 	S5(r2, r4, r3, r0, r1); store_and_load_keys(r1, r2, r4, r0, 20, 16);
240 	S6(r1, r2, r4, r0, r3); store_and_load_keys(r4, r3, r2, r0, 16, 12);
241 	S7(r4, r3, r2, r0, r1); store_and_load_keys(r1, r2, r0, r4, 12, 8);
242 	S0(r1, r2, r0, r4, r3); store_and_load_keys(r0, r2, r4, r1, 8, 4);
243 	S1(r0, r2, r4, r1, r3); store_and_load_keys(r3, r4, r1, r0, 4, 0);
244 	S2(r3, r4, r1, r0, r2); store_and_load_keys(r2, r4, r3, r0, 0, -4);
245 	S3(r2, r4, r3, r0, r1); store_and_load_keys(r0, r1, r4, r2, -4, -8);
246 	S4(r0, r1, r4, r2, r3); store_and_load_keys(r1, r4, r2, r3, -8, -12);
247 	S5(r1, r4, r2, r3, r0); store_and_load_keys(r0, r1, r4, r3, -12, -16);
248 	S6(r0, r1, r4, r3, r2); store_and_load_keys(r4, r2, r1, r3, -16, -20);
249 	S7(r4, r2, r1, r3, r0); store_and_load_keys(r0, r1, r3, r4, -20, -24);
250 	S0(r0, r1, r3, r4, r2); store_and_load_keys(r3, r1, r4, r0, -24, -28);
251 	k -= 50;
252 	S1(r3, r1, r4, r0, r2); store_and_load_keys(r2, r4, r0, r3, 22, 18);
253 	S2(r2, r4, r0, r3, r1); store_and_load_keys(r1, r4, r2, r3, 18, 14);
254 	S3(r1, r4, r2, r3, r0); store_and_load_keys(r3, r0, r4, r1, 14, 10);
255 	S4(r3, r0, r4, r1, r2); store_and_load_keys(r0, r4, r1, r2, 10, 6);
256 	S5(r0, r4, r1, r2, r3); store_and_load_keys(r3, r0, r4, r2, 6, 2);
257 	S6(r3, r0, r4, r2, r1); store_and_load_keys(r4, r1, r0, r2, 2, -2);
258 	S7(r4, r1, r0, r2, r3); store_and_load_keys(r3, r0, r2, r4, -2, -6);
259 	S0(r3, r0, r2, r4, r1); store_and_load_keys(r2, r0, r4, r3, -6, -10);
260 	S1(r2, r0, r4, r3, r1); store_and_load_keys(r1, r4, r3, r2, -10, -14);
261 	S2(r1, r4, r3, r2, r0); store_and_load_keys(r0, r4, r1, r2, -14, -18);
262 	S3(r0, r4, r1, r2, r3); store_and_load_keys(r2, r3, r4, r0, -18, -22);
263 	k -= 50;
264 	S4(r2, r3, r4, r0, r1); store_and_load_keys(r3, r4, r0, r1, 28, 24);
265 	S5(r3, r4, r0, r1, r2); store_and_load_keys(r2, r3, r4, r1, 24, 20);
266 	S6(r2, r3, r4, r1, r0); store_and_load_keys(r4, r0, r3, r1, 20, 16);
267 	S7(r4, r0, r3, r1, r2); store_and_load_keys(r2, r3, r1, r4, 16, 12);
268 	S0(r2, r3, r1, r4, r0); store_and_load_keys(r1, r3, r4, r2, 12, 8);
269 	S1(r1, r3, r4, r2, r0); store_and_load_keys(r0, r4, r2, r1, 8, 4);
270 	S2(r0, r4, r2, r1, r3); store_and_load_keys(r3, r4, r0, r1, 4, 0);
271 	S3(r3, r4, r0, r1, r2); storekeys(r1, r2, r4, r3, 0);
272 }
273 
274 int __serpent_setkey(struct serpent_ctx *ctx, const u8 *key,
275 		     unsigned int keylen)
276 {
277 	u32 *k = ctx->expkey;
278 	u8  *k8 = (u8 *)k;
279 	u32 r0, r1, r2, r3, r4;
280 	int i;
281 
282 	/* Copy key, add padding */
283 
284 	for (i = 0; i < keylen; ++i)
285 		k8[i] = key[i];
286 	if (i < SERPENT_MAX_KEY_SIZE)
287 		k8[i++] = 1;
288 	while (i < SERPENT_MAX_KEY_SIZE)
289 		k8[i++] = 0;
290 
291 	/* Expand key using polynomial */
292 
293 	r0 = le32_to_cpu(k[3]);
294 	r1 = le32_to_cpu(k[4]);
295 	r2 = le32_to_cpu(k[5]);
296 	r3 = le32_to_cpu(k[6]);
297 	r4 = le32_to_cpu(k[7]);
298 
299 	keyiter(le32_to_cpu(k[0]), r0, r4, r2, 0, 0);
300 	keyiter(le32_to_cpu(k[1]), r1, r0, r3, 1, 1);
301 	keyiter(le32_to_cpu(k[2]), r2, r1, r4, 2, 2);
302 	keyiter(le32_to_cpu(k[3]), r3, r2, r0, 3, 3);
303 	keyiter(le32_to_cpu(k[4]), r4, r3, r1, 4, 4);
304 	keyiter(le32_to_cpu(k[5]), r0, r4, r2, 5, 5);
305 	keyiter(le32_to_cpu(k[6]), r1, r0, r3, 6, 6);
306 	keyiter(le32_to_cpu(k[7]), r2, r1, r4, 7, 7);
307 
308 	keyiter(k[0], r3, r2, r0, 8, 8);
309 	keyiter(k[1], r4, r3, r1, 9, 9);
310 	keyiter(k[2], r0, r4, r2, 10, 10);
311 	keyiter(k[3], r1, r0, r3, 11, 11);
312 	keyiter(k[4], r2, r1, r4, 12, 12);
313 	keyiter(k[5], r3, r2, r0, 13, 13);
314 	keyiter(k[6], r4, r3, r1, 14, 14);
315 	keyiter(k[7], r0, r4, r2, 15, 15);
316 	keyiter(k[8], r1, r0, r3, 16, 16);
317 	keyiter(k[9], r2, r1, r4, 17, 17);
318 	keyiter(k[10], r3, r2, r0, 18, 18);
319 	keyiter(k[11], r4, r3, r1, 19, 19);
320 	keyiter(k[12], r0, r4, r2, 20, 20);
321 	keyiter(k[13], r1, r0, r3, 21, 21);
322 	keyiter(k[14], r2, r1, r4, 22, 22);
323 	keyiter(k[15], r3, r2, r0, 23, 23);
324 	keyiter(k[16], r4, r3, r1, 24, 24);
325 	keyiter(k[17], r0, r4, r2, 25, 25);
326 	keyiter(k[18], r1, r0, r3, 26, 26);
327 	keyiter(k[19], r2, r1, r4, 27, 27);
328 	keyiter(k[20], r3, r2, r0, 28, 28);
329 	keyiter(k[21], r4, r3, r1, 29, 29);
330 	keyiter(k[22], r0, r4, r2, 30, 30);
331 	keyiter(k[23], r1, r0, r3, 31, 31);
332 
333 	k += 50;
334 
335 	keyiter(k[-26], r2, r1, r4, 32, -18);
336 	keyiter(k[-25], r3, r2, r0, 33, -17);
337 	keyiter(k[-24], r4, r3, r1, 34, -16);
338 	keyiter(k[-23], r0, r4, r2, 35, -15);
339 	keyiter(k[-22], r1, r0, r3, 36, -14);
340 	keyiter(k[-21], r2, r1, r4, 37, -13);
341 	keyiter(k[-20], r3, r2, r0, 38, -12);
342 	keyiter(k[-19], r4, r3, r1, 39, -11);
343 	keyiter(k[-18], r0, r4, r2, 40, -10);
344 	keyiter(k[-17], r1, r0, r3, 41, -9);
345 	keyiter(k[-16], r2, r1, r4, 42, -8);
346 	keyiter(k[-15], r3, r2, r0, 43, -7);
347 	keyiter(k[-14], r4, r3, r1, 44, -6);
348 	keyiter(k[-13], r0, r4, r2, 45, -5);
349 	keyiter(k[-12], r1, r0, r3, 46, -4);
350 	keyiter(k[-11], r2, r1, r4, 47, -3);
351 	keyiter(k[-10], r3, r2, r0, 48, -2);
352 	keyiter(k[-9], r4, r3, r1, 49, -1);
353 	keyiter(k[-8], r0, r4, r2, 50, 0);
354 	keyiter(k[-7], r1, r0, r3, 51, 1);
355 	keyiter(k[-6], r2, r1, r4, 52, 2);
356 	keyiter(k[-5], r3, r2, r0, 53, 3);
357 	keyiter(k[-4], r4, r3, r1, 54, 4);
358 	keyiter(k[-3], r0, r4, r2, 55, 5);
359 	keyiter(k[-2], r1, r0, r3, 56, 6);
360 	keyiter(k[-1], r2, r1, r4, 57, 7);
361 	keyiter(k[0], r3, r2, r0, 58, 8);
362 	keyiter(k[1], r4, r3, r1, 59, 9);
363 	keyiter(k[2], r0, r4, r2, 60, 10);
364 	keyiter(k[3], r1, r0, r3, 61, 11);
365 	keyiter(k[4], r2, r1, r4, 62, 12);
366 	keyiter(k[5], r3, r2, r0, 63, 13);
367 	keyiter(k[6], r4, r3, r1, 64, 14);
368 	keyiter(k[7], r0, r4, r2, 65, 15);
369 	keyiter(k[8], r1, r0, r3, 66, 16);
370 	keyiter(k[9], r2, r1, r4, 67, 17);
371 	keyiter(k[10], r3, r2, r0, 68, 18);
372 	keyiter(k[11], r4, r3, r1, 69, 19);
373 	keyiter(k[12], r0, r4, r2, 70, 20);
374 	keyiter(k[13], r1, r0, r3, 71, 21);
375 	keyiter(k[14], r2, r1, r4, 72, 22);
376 	keyiter(k[15], r3, r2, r0, 73, 23);
377 	keyiter(k[16], r4, r3, r1, 74, 24);
378 	keyiter(k[17], r0, r4, r2, 75, 25);
379 	keyiter(k[18], r1, r0, r3, 76, 26);
380 	keyiter(k[19], r2, r1, r4, 77, 27);
381 	keyiter(k[20], r3, r2, r0, 78, 28);
382 	keyiter(k[21], r4, r3, r1, 79, 29);
383 	keyiter(k[22], r0, r4, r2, 80, 30);
384 	keyiter(k[23], r1, r0, r3, 81, 31);
385 
386 	k += 50;
387 
388 	keyiter(k[-26], r2, r1, r4, 82, -18);
389 	keyiter(k[-25], r3, r2, r0, 83, -17);
390 	keyiter(k[-24], r4, r3, r1, 84, -16);
391 	keyiter(k[-23], r0, r4, r2, 85, -15);
392 	keyiter(k[-22], r1, r0, r3, 86, -14);
393 	keyiter(k[-21], r2, r1, r4, 87, -13);
394 	keyiter(k[-20], r3, r2, r0, 88, -12);
395 	keyiter(k[-19], r4, r3, r1, 89, -11);
396 	keyiter(k[-18], r0, r4, r2, 90, -10);
397 	keyiter(k[-17], r1, r0, r3, 91, -9);
398 	keyiter(k[-16], r2, r1, r4, 92, -8);
399 	keyiter(k[-15], r3, r2, r0, 93, -7);
400 	keyiter(k[-14], r4, r3, r1, 94, -6);
401 	keyiter(k[-13], r0, r4, r2, 95, -5);
402 	keyiter(k[-12], r1, r0, r3, 96, -4);
403 	keyiter(k[-11], r2, r1, r4, 97, -3);
404 	keyiter(k[-10], r3, r2, r0, 98, -2);
405 	keyiter(k[-9], r4, r3, r1, 99, -1);
406 	keyiter(k[-8], r0, r4, r2, 100, 0);
407 	keyiter(k[-7], r1, r0, r3, 101, 1);
408 	keyiter(k[-6], r2, r1, r4, 102, 2);
409 	keyiter(k[-5], r3, r2, r0, 103, 3);
410 	keyiter(k[-4], r4, r3, r1, 104, 4);
411 	keyiter(k[-3], r0, r4, r2, 105, 5);
412 	keyiter(k[-2], r1, r0, r3, 106, 6);
413 	keyiter(k[-1], r2, r1, r4, 107, 7);
414 	keyiter(k[0], r3, r2, r0, 108, 8);
415 	keyiter(k[1], r4, r3, r1, 109, 9);
416 	keyiter(k[2], r0, r4, r2, 110, 10);
417 	keyiter(k[3], r1, r0, r3, 111, 11);
418 	keyiter(k[4], r2, r1, r4, 112, 12);
419 	keyiter(k[5], r3, r2, r0, 113, 13);
420 	keyiter(k[6], r4, r3, r1, 114, 14);
421 	keyiter(k[7], r0, r4, r2, 115, 15);
422 	keyiter(k[8], r1, r0, r3, 116, 16);
423 	keyiter(k[9], r2, r1, r4, 117, 17);
424 	keyiter(k[10], r3, r2, r0, 118, 18);
425 	keyiter(k[11], r4, r3, r1, 119, 19);
426 	keyiter(k[12], r0, r4, r2, 120, 20);
427 	keyiter(k[13], r1, r0, r3, 121, 21);
428 	keyiter(k[14], r2, r1, r4, 122, 22);
429 	keyiter(k[15], r3, r2, r0, 123, 23);
430 	keyiter(k[16], r4, r3, r1, 124, 24);
431 	keyiter(k[17], r0, r4, r2, 125, 25);
432 	keyiter(k[18], r1, r0, r3, 126, 26);
433 	keyiter(k[19], r2, r1, r4, 127, 27);
434 	keyiter(k[20], r3, r2, r0, 128, 28);
435 	keyiter(k[21], r4, r3, r1, 129, 29);
436 	keyiter(k[22], r0, r4, r2, 130, 30);
437 	keyiter(k[23], r1, r0, r3, 131, 31);
438 
439 	/* Apply S-boxes */
440 	__serpent_setkey_sbox(r0, r1, r2, r3, r4, ctx->expkey);
441 
442 	return 0;
443 }
444 EXPORT_SYMBOL_GPL(__serpent_setkey);
445 
446 int serpent_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
447 {
448 	return __serpent_setkey(crypto_tfm_ctx(tfm), key, keylen);
449 }
450 EXPORT_SYMBOL_GPL(serpent_setkey);
451 
452 void __serpent_encrypt(const void *c, u8 *dst, const u8 *src)
453 {
454 	const struct serpent_ctx *ctx = c;
455 	const u32 *k = ctx->expkey;
456 	const __le32 *s = (const __le32 *)src;
457 	__le32	*d = (__le32 *)dst;
458 	u32	r0, r1, r2, r3, r4;
459 
460 /*
461  * Note: The conversions between u8* and u32* might cause trouble
462  * on architectures with stricter alignment rules than x86
463  */
464 
465 	r0 = le32_to_cpu(s[0]);
466 	r1 = le32_to_cpu(s[1]);
467 	r2 = le32_to_cpu(s[2]);
468 	r3 = le32_to_cpu(s[3]);
469 
470 					K(r0, r1, r2, r3, 0);
471 	S0(r0, r1, r2, r3, r4);		LK(r2, r1, r3, r0, r4, 1);
472 	S1(r2, r1, r3, r0, r4);		LK(r4, r3, r0, r2, r1, 2);
473 	S2(r4, r3, r0, r2, r1);		LK(r1, r3, r4, r2, r0, 3);
474 	S3(r1, r3, r4, r2, r0);		LK(r2, r0, r3, r1, r4, 4);
475 	S4(r2, r0, r3, r1, r4);		LK(r0, r3, r1, r4, r2, 5);
476 	S5(r0, r3, r1, r4, r2);		LK(r2, r0, r3, r4, r1, 6);
477 	S6(r2, r0, r3, r4, r1);		LK(r3, r1, r0, r4, r2, 7);
478 	S7(r3, r1, r0, r4, r2);		LK(r2, r0, r4, r3, r1, 8);
479 	S0(r2, r0, r4, r3, r1);		LK(r4, r0, r3, r2, r1, 9);
480 	S1(r4, r0, r3, r2, r1);		LK(r1, r3, r2, r4, r0, 10);
481 	S2(r1, r3, r2, r4, r0);		LK(r0, r3, r1, r4, r2, 11);
482 	S3(r0, r3, r1, r4, r2);		LK(r4, r2, r3, r0, r1, 12);
483 	S4(r4, r2, r3, r0, r1);		LK(r2, r3, r0, r1, r4, 13);
484 	S5(r2, r3, r0, r1, r4);		LK(r4, r2, r3, r1, r0, 14);
485 	S6(r4, r2, r3, r1, r0);		LK(r3, r0, r2, r1, r4, 15);
486 	S7(r3, r0, r2, r1, r4);		LK(r4, r2, r1, r3, r0, 16);
487 	S0(r4, r2, r1, r3, r0);		LK(r1, r2, r3, r4, r0, 17);
488 	S1(r1, r2, r3, r4, r0);		LK(r0, r3, r4, r1, r2, 18);
489 	S2(r0, r3, r4, r1, r2);		LK(r2, r3, r0, r1, r4, 19);
490 	S3(r2, r3, r0, r1, r4);		LK(r1, r4, r3, r2, r0, 20);
491 	S4(r1, r4, r3, r2, r0);		LK(r4, r3, r2, r0, r1, 21);
492 	S5(r4, r3, r2, r0, r1);		LK(r1, r4, r3, r0, r2, 22);
493 	S6(r1, r4, r3, r0, r2);		LK(r3, r2, r4, r0, r1, 23);
494 	S7(r3, r2, r4, r0, r1);		LK(r1, r4, r0, r3, r2, 24);
495 	S0(r1, r4, r0, r3, r2);		LK(r0, r4, r3, r1, r2, 25);
496 	S1(r0, r4, r3, r1, r2);		LK(r2, r3, r1, r0, r4, 26);
497 	S2(r2, r3, r1, r0, r4);		LK(r4, r3, r2, r0, r1, 27);
498 	S3(r4, r3, r2, r0, r1);		LK(r0, r1, r3, r4, r2, 28);
499 	S4(r0, r1, r3, r4, r2);		LK(r1, r3, r4, r2, r0, 29);
500 	S5(r1, r3, r4, r2, r0);		LK(r0, r1, r3, r2, r4, 30);
501 	S6(r0, r1, r3, r2, r4);		LK(r3, r4, r1, r2, r0, 31);
502 	S7(r3, r4, r1, r2, r0);		K(r0, r1, r2, r3, 32);
503 
504 	d[0] = cpu_to_le32(r0);
505 	d[1] = cpu_to_le32(r1);
506 	d[2] = cpu_to_le32(r2);
507 	d[3] = cpu_to_le32(r3);
508 }
509 EXPORT_SYMBOL_GPL(__serpent_encrypt);
510 
511 static void serpent_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
512 {
513 	struct serpent_ctx *ctx = crypto_tfm_ctx(tfm);
514 
515 	__serpent_encrypt(ctx, dst, src);
516 }
517 
518 void __serpent_decrypt(const void *c, u8 *dst, const u8 *src)
519 {
520 	const struct serpent_ctx *ctx = c;
521 	const u32 *k = ctx->expkey;
522 	const __le32 *s = (const __le32 *)src;
523 	__le32	*d = (__le32 *)dst;
524 	u32	r0, r1, r2, r3, r4;
525 
526 	r0 = le32_to_cpu(s[0]);
527 	r1 = le32_to_cpu(s[1]);
528 	r2 = le32_to_cpu(s[2]);
529 	r3 = le32_to_cpu(s[3]);
530 
531 					K(r0, r1, r2, r3, 32);
532 	SI7(r0, r1, r2, r3, r4);	KL(r1, r3, r0, r4, r2, 31);
533 	SI6(r1, r3, r0, r4, r2);	KL(r0, r2, r4, r1, r3, 30);
534 	SI5(r0, r2, r4, r1, r3);	KL(r2, r3, r0, r4, r1, 29);
535 	SI4(r2, r3, r0, r4, r1);	KL(r2, r0, r1, r4, r3, 28);
536 	SI3(r2, r0, r1, r4, r3);	KL(r1, r2, r3, r4, r0, 27);
537 	SI2(r1, r2, r3, r4, r0);	KL(r2, r0, r4, r3, r1, 26);
538 	SI1(r2, r0, r4, r3, r1);	KL(r1, r0, r4, r3, r2, 25);
539 	SI0(r1, r0, r4, r3, r2);	KL(r4, r2, r0, r1, r3, 24);
540 	SI7(r4, r2, r0, r1, r3);	KL(r2, r1, r4, r3, r0, 23);
541 	SI6(r2, r1, r4, r3, r0);	KL(r4, r0, r3, r2, r1, 22);
542 	SI5(r4, r0, r3, r2, r1);	KL(r0, r1, r4, r3, r2, 21);
543 	SI4(r0, r1, r4, r3, r2);	KL(r0, r4, r2, r3, r1, 20);
544 	SI3(r0, r4, r2, r3, r1);	KL(r2, r0, r1, r3, r4, 19);
545 	SI2(r2, r0, r1, r3, r4);	KL(r0, r4, r3, r1, r2, 18);
546 	SI1(r0, r4, r3, r1, r2);	KL(r2, r4, r3, r1, r0, 17);
547 	SI0(r2, r4, r3, r1, r0);	KL(r3, r0, r4, r2, r1, 16);
548 	SI7(r3, r0, r4, r2, r1);	KL(r0, r2, r3, r1, r4, 15);
549 	SI6(r0, r2, r3, r1, r4);	KL(r3, r4, r1, r0, r2, 14);
550 	SI5(r3, r4, r1, r0, r2);	KL(r4, r2, r3, r1, r0, 13);
551 	SI4(r4, r2, r3, r1, r0);	KL(r4, r3, r0, r1, r2, 12);
552 	SI3(r4, r3, r0, r1, r2);	KL(r0, r4, r2, r1, r3, 11);
553 	SI2(r0, r4, r2, r1, r3);	KL(r4, r3, r1, r2, r0, 10);
554 	SI1(r4, r3, r1, r2, r0);	KL(r0, r3, r1, r2, r4, 9);
555 	SI0(r0, r3, r1, r2, r4);	KL(r1, r4, r3, r0, r2, 8);
556 	SI7(r1, r4, r3, r0, r2);	KL(r4, r0, r1, r2, r3, 7);
557 	SI6(r4, r0, r1, r2, r3);	KL(r1, r3, r2, r4, r0, 6);
558 	SI5(r1, r3, r2, r4, r0);	KL(r3, r0, r1, r2, r4, 5);
559 	SI4(r3, r0, r1, r2, r4);	KL(r3, r1, r4, r2, r0, 4);
560 	SI3(r3, r1, r4, r2, r0);	KL(r4, r3, r0, r2, r1, 3);
561 	SI2(r4, r3, r0, r2, r1);	KL(r3, r1, r2, r0, r4, 2);
562 	SI1(r3, r1, r2, r0, r4);	KL(r4, r1, r2, r0, r3, 1);
563 	SI0(r4, r1, r2, r0, r3);	K(r2, r3, r1, r4, 0);
564 
565 	d[0] = cpu_to_le32(r2);
566 	d[1] = cpu_to_le32(r3);
567 	d[2] = cpu_to_le32(r1);
568 	d[3] = cpu_to_le32(r4);
569 }
570 EXPORT_SYMBOL_GPL(__serpent_decrypt);
571 
572 static void serpent_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
573 {
574 	struct serpent_ctx *ctx = crypto_tfm_ctx(tfm);
575 
576 	__serpent_decrypt(ctx, dst, src);
577 }
578 
579 static int tnepres_setkey(struct crypto_tfm *tfm, const u8 *key,
580 			  unsigned int keylen)
581 {
582 	u8 rev_key[SERPENT_MAX_KEY_SIZE];
583 	int i;
584 
585 	for (i = 0; i < keylen; ++i)
586 		rev_key[keylen - i - 1] = key[i];
587 
588 	return serpent_setkey(tfm, rev_key, keylen);
589 }
590 
591 static void tnepres_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
592 {
593 	const u32 * const s = (const u32 * const)src;
594 	u32 * const d = (u32 * const)dst;
595 
596 	u32 rs[4], rd[4];
597 
598 	rs[0] = swab32(s[3]);
599 	rs[1] = swab32(s[2]);
600 	rs[2] = swab32(s[1]);
601 	rs[3] = swab32(s[0]);
602 
603 	serpent_encrypt(tfm, (u8 *)rd, (u8 *)rs);
604 
605 	d[0] = swab32(rd[3]);
606 	d[1] = swab32(rd[2]);
607 	d[2] = swab32(rd[1]);
608 	d[3] = swab32(rd[0]);
609 }
610 
611 static void tnepres_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
612 {
613 	const u32 * const s = (const u32 * const)src;
614 	u32 * const d = (u32 * const)dst;
615 
616 	u32 rs[4], rd[4];
617 
618 	rs[0] = swab32(s[3]);
619 	rs[1] = swab32(s[2]);
620 	rs[2] = swab32(s[1]);
621 	rs[3] = swab32(s[0]);
622 
623 	serpent_decrypt(tfm, (u8 *)rd, (u8 *)rs);
624 
625 	d[0] = swab32(rd[3]);
626 	d[1] = swab32(rd[2]);
627 	d[2] = swab32(rd[1]);
628 	d[3] = swab32(rd[0]);
629 }
630 
631 static struct crypto_alg srp_algs[2] = { {
632 	.cra_name		=	"serpent",
633 	.cra_driver_name	=	"serpent-generic",
634 	.cra_priority		=	100,
635 	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
636 	.cra_blocksize		=	SERPENT_BLOCK_SIZE,
637 	.cra_ctxsize		=	sizeof(struct serpent_ctx),
638 	.cra_alignmask		=	3,
639 	.cra_module		=	THIS_MODULE,
640 	.cra_u			=	{ .cipher = {
641 	.cia_min_keysize	=	SERPENT_MIN_KEY_SIZE,
642 	.cia_max_keysize	=	SERPENT_MAX_KEY_SIZE,
643 	.cia_setkey		=	serpent_setkey,
644 	.cia_encrypt		=	serpent_encrypt,
645 	.cia_decrypt		=	serpent_decrypt } }
646 }, {
647 	.cra_name		=	"tnepres",
648 	.cra_driver_name	=	"tnepres-generic",
649 	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
650 	.cra_blocksize		=	SERPENT_BLOCK_SIZE,
651 	.cra_ctxsize		=	sizeof(struct serpent_ctx),
652 	.cra_alignmask		=	3,
653 	.cra_module		=	THIS_MODULE,
654 	.cra_u			=	{ .cipher = {
655 	.cia_min_keysize	=	SERPENT_MIN_KEY_SIZE,
656 	.cia_max_keysize	=	SERPENT_MAX_KEY_SIZE,
657 	.cia_setkey		=	tnepres_setkey,
658 	.cia_encrypt		=	tnepres_encrypt,
659 	.cia_decrypt		=	tnepres_decrypt } }
660 } };
661 
662 static int __init serpent_mod_init(void)
663 {
664 	return crypto_register_algs(srp_algs, ARRAY_SIZE(srp_algs));
665 }
666 
667 static void __exit serpent_mod_fini(void)
668 {
669 	crypto_unregister_algs(srp_algs, ARRAY_SIZE(srp_algs));
670 }
671 
672 subsys_initcall(serpent_mod_init);
673 module_exit(serpent_mod_fini);
674 
675 MODULE_LICENSE("GPL");
676 MODULE_DESCRIPTION("Serpent and tnepres (kerneli compatible serpent reversed) Cipher Algorithm");
677 MODULE_AUTHOR("Dag Arne Osvik <osvik@ii.uib.no>");
678 MODULE_ALIAS_CRYPTO("tnepres");
679 MODULE_ALIAS_CRYPTO("serpent");
680 MODULE_ALIAS_CRYPTO("serpent-generic");
681