1 /*
2  * Glue Code for AVX assembler version of Twofish Cipher
3  *
4  * Copyright (C) 2012 Johannes Goetzfried
5  *     <Johannes.Goetzfried@informatik.stud.uni-erlangen.de>
6  *
7  * Copyright © 2013 Jussi Kivilinna <jussi.kivilinna@iki.fi>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
22  * USA
23  *
24  */
25 
26 #include <linux/module.h>
27 #include <linux/types.h>
28 #include <linux/crypto.h>
29 #include <linux/err.h>
30 #include <crypto/algapi.h>
31 #include <crypto/internal/simd.h>
32 #include <crypto/twofish.h>
33 #include <crypto/xts.h>
34 #include <asm/crypto/glue_helper.h>
35 #include <asm/crypto/twofish.h>
36 
37 #define TWOFISH_PARALLEL_BLOCKS 8
38 
39 /* 8-way parallel cipher functions */
40 asmlinkage void twofish_ecb_enc_8way(struct twofish_ctx *ctx, u8 *dst,
41 				     const u8 *src);
42 asmlinkage void twofish_ecb_dec_8way(struct twofish_ctx *ctx, u8 *dst,
43 				     const u8 *src);
44 
45 asmlinkage void twofish_cbc_dec_8way(struct twofish_ctx *ctx, u8 *dst,
46 				     const u8 *src);
47 asmlinkage void twofish_ctr_8way(struct twofish_ctx *ctx, u8 *dst,
48 				 const u8 *src, le128 *iv);
49 
50 asmlinkage void twofish_xts_enc_8way(struct twofish_ctx *ctx, u8 *dst,
51 				     const u8 *src, le128 *iv);
52 asmlinkage void twofish_xts_dec_8way(struct twofish_ctx *ctx, u8 *dst,
53 				     const u8 *src, le128 *iv);
54 
55 static int twofish_setkey_skcipher(struct crypto_skcipher *tfm,
56 				   const u8 *key, unsigned int keylen)
57 {
58 	return twofish_setkey(&tfm->base, key, keylen);
59 }
60 
61 static inline void twofish_enc_blk_3way(struct twofish_ctx *ctx, u8 *dst,
62 					const u8 *src)
63 {
64 	__twofish_enc_blk_3way(ctx, dst, src, false);
65 }
66 
67 static void twofish_xts_enc(void *ctx, u128 *dst, const u128 *src, le128 *iv)
68 {
69 	glue_xts_crypt_128bit_one(ctx, dst, src, iv,
70 				  GLUE_FUNC_CAST(twofish_enc_blk));
71 }
72 
73 static void twofish_xts_dec(void *ctx, u128 *dst, const u128 *src, le128 *iv)
74 {
75 	glue_xts_crypt_128bit_one(ctx, dst, src, iv,
76 				  GLUE_FUNC_CAST(twofish_dec_blk));
77 }
78 
79 struct twofish_xts_ctx {
80 	struct twofish_ctx tweak_ctx;
81 	struct twofish_ctx crypt_ctx;
82 };
83 
84 static int xts_twofish_setkey(struct crypto_skcipher *tfm, const u8 *key,
85 			      unsigned int keylen)
86 {
87 	struct twofish_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
88 	u32 *flags = &tfm->base.crt_flags;
89 	int err;
90 
91 	err = xts_verify_key(tfm, key, keylen);
92 	if (err)
93 		return err;
94 
95 	/* first half of xts-key is for crypt */
96 	err = __twofish_setkey(&ctx->crypt_ctx, key, keylen / 2, flags);
97 	if (err)
98 		return err;
99 
100 	/* second half of xts-key is for tweak */
101 	return __twofish_setkey(&ctx->tweak_ctx, key + keylen / 2, keylen / 2,
102 				flags);
103 }
104 
105 static const struct common_glue_ctx twofish_enc = {
106 	.num_funcs = 3,
107 	.fpu_blocks_limit = TWOFISH_PARALLEL_BLOCKS,
108 
109 	.funcs = { {
110 		.num_blocks = TWOFISH_PARALLEL_BLOCKS,
111 		.fn_u = { .ecb = GLUE_FUNC_CAST(twofish_ecb_enc_8way) }
112 	}, {
113 		.num_blocks = 3,
114 		.fn_u = { .ecb = GLUE_FUNC_CAST(twofish_enc_blk_3way) }
115 	}, {
116 		.num_blocks = 1,
117 		.fn_u = { .ecb = GLUE_FUNC_CAST(twofish_enc_blk) }
118 	} }
119 };
120 
121 static const struct common_glue_ctx twofish_ctr = {
122 	.num_funcs = 3,
123 	.fpu_blocks_limit = TWOFISH_PARALLEL_BLOCKS,
124 
125 	.funcs = { {
126 		.num_blocks = TWOFISH_PARALLEL_BLOCKS,
127 		.fn_u = { .ctr = GLUE_CTR_FUNC_CAST(twofish_ctr_8way) }
128 	}, {
129 		.num_blocks = 3,
130 		.fn_u = { .ctr = GLUE_CTR_FUNC_CAST(twofish_enc_blk_ctr_3way) }
131 	}, {
132 		.num_blocks = 1,
133 		.fn_u = { .ctr = GLUE_CTR_FUNC_CAST(twofish_enc_blk_ctr) }
134 	} }
135 };
136 
137 static const struct common_glue_ctx twofish_enc_xts = {
138 	.num_funcs = 2,
139 	.fpu_blocks_limit = TWOFISH_PARALLEL_BLOCKS,
140 
141 	.funcs = { {
142 		.num_blocks = TWOFISH_PARALLEL_BLOCKS,
143 		.fn_u = { .xts = GLUE_XTS_FUNC_CAST(twofish_xts_enc_8way) }
144 	}, {
145 		.num_blocks = 1,
146 		.fn_u = { .xts = GLUE_XTS_FUNC_CAST(twofish_xts_enc) }
147 	} }
148 };
149 
150 static const struct common_glue_ctx twofish_dec = {
151 	.num_funcs = 3,
152 	.fpu_blocks_limit = TWOFISH_PARALLEL_BLOCKS,
153 
154 	.funcs = { {
155 		.num_blocks = TWOFISH_PARALLEL_BLOCKS,
156 		.fn_u = { .ecb = GLUE_FUNC_CAST(twofish_ecb_dec_8way) }
157 	}, {
158 		.num_blocks = 3,
159 		.fn_u = { .ecb = GLUE_FUNC_CAST(twofish_dec_blk_3way) }
160 	}, {
161 		.num_blocks = 1,
162 		.fn_u = { .ecb = GLUE_FUNC_CAST(twofish_dec_blk) }
163 	} }
164 };
165 
166 static const struct common_glue_ctx twofish_dec_cbc = {
167 	.num_funcs = 3,
168 	.fpu_blocks_limit = TWOFISH_PARALLEL_BLOCKS,
169 
170 	.funcs = { {
171 		.num_blocks = TWOFISH_PARALLEL_BLOCKS,
172 		.fn_u = { .cbc = GLUE_CBC_FUNC_CAST(twofish_cbc_dec_8way) }
173 	}, {
174 		.num_blocks = 3,
175 		.fn_u = { .cbc = GLUE_CBC_FUNC_CAST(twofish_dec_blk_cbc_3way) }
176 	}, {
177 		.num_blocks = 1,
178 		.fn_u = { .cbc = GLUE_CBC_FUNC_CAST(twofish_dec_blk) }
179 	} }
180 };
181 
182 static const struct common_glue_ctx twofish_dec_xts = {
183 	.num_funcs = 2,
184 	.fpu_blocks_limit = TWOFISH_PARALLEL_BLOCKS,
185 
186 	.funcs = { {
187 		.num_blocks = TWOFISH_PARALLEL_BLOCKS,
188 		.fn_u = { .xts = GLUE_XTS_FUNC_CAST(twofish_xts_dec_8way) }
189 	}, {
190 		.num_blocks = 1,
191 		.fn_u = { .xts = GLUE_XTS_FUNC_CAST(twofish_xts_dec) }
192 	} }
193 };
194 
195 static int ecb_encrypt(struct skcipher_request *req)
196 {
197 	return glue_ecb_req_128bit(&twofish_enc, req);
198 }
199 
200 static int ecb_decrypt(struct skcipher_request *req)
201 {
202 	return glue_ecb_req_128bit(&twofish_dec, req);
203 }
204 
205 static int cbc_encrypt(struct skcipher_request *req)
206 {
207 	return glue_cbc_encrypt_req_128bit(GLUE_FUNC_CAST(twofish_enc_blk),
208 					   req);
209 }
210 
211 static int cbc_decrypt(struct skcipher_request *req)
212 {
213 	return glue_cbc_decrypt_req_128bit(&twofish_dec_cbc, req);
214 }
215 
216 static int ctr_crypt(struct skcipher_request *req)
217 {
218 	return glue_ctr_req_128bit(&twofish_ctr, req);
219 }
220 
221 static int xts_encrypt(struct skcipher_request *req)
222 {
223 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
224 	struct twofish_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
225 
226 	return glue_xts_req_128bit(&twofish_enc_xts, req,
227 				   XTS_TWEAK_CAST(twofish_enc_blk),
228 				   &ctx->tweak_ctx, &ctx->crypt_ctx);
229 }
230 
231 static int xts_decrypt(struct skcipher_request *req)
232 {
233 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
234 	struct twofish_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
235 
236 	return glue_xts_req_128bit(&twofish_dec_xts, req,
237 				   XTS_TWEAK_CAST(twofish_enc_blk),
238 				   &ctx->tweak_ctx, &ctx->crypt_ctx);
239 }
240 
241 static struct skcipher_alg twofish_algs[] = {
242 	{
243 		.base.cra_name		= "__ecb(twofish)",
244 		.base.cra_driver_name	= "__ecb-twofish-avx",
245 		.base.cra_priority	= 400,
246 		.base.cra_flags		= CRYPTO_ALG_INTERNAL,
247 		.base.cra_blocksize	= TF_BLOCK_SIZE,
248 		.base.cra_ctxsize	= sizeof(struct twofish_ctx),
249 		.base.cra_module	= THIS_MODULE,
250 		.min_keysize		= TF_MIN_KEY_SIZE,
251 		.max_keysize		= TF_MAX_KEY_SIZE,
252 		.setkey			= twofish_setkey_skcipher,
253 		.encrypt		= ecb_encrypt,
254 		.decrypt		= ecb_decrypt,
255 	}, {
256 		.base.cra_name		= "__cbc(twofish)",
257 		.base.cra_driver_name	= "__cbc-twofish-avx",
258 		.base.cra_priority	= 400,
259 		.base.cra_flags		= CRYPTO_ALG_INTERNAL,
260 		.base.cra_blocksize	= TF_BLOCK_SIZE,
261 		.base.cra_ctxsize	= sizeof(struct twofish_ctx),
262 		.base.cra_module	= THIS_MODULE,
263 		.min_keysize		= TF_MIN_KEY_SIZE,
264 		.max_keysize		= TF_MAX_KEY_SIZE,
265 		.ivsize			= TF_BLOCK_SIZE,
266 		.setkey			= twofish_setkey_skcipher,
267 		.encrypt		= cbc_encrypt,
268 		.decrypt		= cbc_decrypt,
269 	}, {
270 		.base.cra_name		= "__ctr(twofish)",
271 		.base.cra_driver_name	= "__ctr-twofish-avx",
272 		.base.cra_priority	= 400,
273 		.base.cra_flags		= CRYPTO_ALG_INTERNAL,
274 		.base.cra_blocksize	= 1,
275 		.base.cra_ctxsize	= sizeof(struct twofish_ctx),
276 		.base.cra_module	= THIS_MODULE,
277 		.min_keysize		= TF_MIN_KEY_SIZE,
278 		.max_keysize		= TF_MAX_KEY_SIZE,
279 		.ivsize			= TF_BLOCK_SIZE,
280 		.chunksize		= TF_BLOCK_SIZE,
281 		.setkey			= twofish_setkey_skcipher,
282 		.encrypt		= ctr_crypt,
283 		.decrypt		= ctr_crypt,
284 	}, {
285 		.base.cra_name		= "__xts(twofish)",
286 		.base.cra_driver_name	= "__xts-twofish-avx",
287 		.base.cra_priority	= 400,
288 		.base.cra_flags		= CRYPTO_ALG_INTERNAL,
289 		.base.cra_blocksize	= TF_BLOCK_SIZE,
290 		.base.cra_ctxsize	= sizeof(struct twofish_xts_ctx),
291 		.base.cra_module	= THIS_MODULE,
292 		.min_keysize		= 2 * TF_MIN_KEY_SIZE,
293 		.max_keysize		= 2 * TF_MAX_KEY_SIZE,
294 		.ivsize			= TF_BLOCK_SIZE,
295 		.setkey			= xts_twofish_setkey,
296 		.encrypt		= xts_encrypt,
297 		.decrypt		= xts_decrypt,
298 	},
299 };
300 
301 static struct simd_skcipher_alg *twofish_simd_algs[ARRAY_SIZE(twofish_algs)];
302 
303 static int __init twofish_init(void)
304 {
305 	const char *feature_name;
306 
307 	if (!cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM, &feature_name)) {
308 		pr_info("CPU feature '%s' is not supported.\n", feature_name);
309 		return -ENODEV;
310 	}
311 
312 	return simd_register_skciphers_compat(twofish_algs,
313 					      ARRAY_SIZE(twofish_algs),
314 					      twofish_simd_algs);
315 }
316 
317 static void __exit twofish_exit(void)
318 {
319 	simd_unregister_skciphers(twofish_algs, ARRAY_SIZE(twofish_algs),
320 				  twofish_simd_algs);
321 }
322 
323 module_init(twofish_init);
324 module_exit(twofish_exit);
325 
326 MODULE_DESCRIPTION("Twofish Cipher Algorithm, AVX optimized");
327 MODULE_LICENSE("GPL");
328 MODULE_ALIAS_CRYPTO("twofish");
329