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Jussi Kivilinna8280daa2011-09-26 16:47:25 +03001/*
2 * Glue Code for 3-way parallel assembler optimized version of Twofish
3 *
4 * Copyright (c) 2011 Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
5 *
6 * CBC & ECB parts based on code (crypto/cbc.c,ecb.c) by:
7 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
8 * CTR part based on code (crypto/ctr.c) by:
9 * (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
24 * USA
25 *
26 */
27
Jussi Kivilinnaa522ee82011-12-20 12:20:16 +020028#include <asm/processor.h>
Jussi Kivilinna8280daa2011-09-26 16:47:25 +030029#include <linux/crypto.h>
30#include <linux/init.h>
31#include <linux/module.h>
32#include <linux/types.h>
33#include <crypto/algapi.h>
34#include <crypto/twofish.h>
35#include <crypto/b128ops.h>
Jussi Kivilinna81559f92011-10-18 13:33:02 +030036#include <crypto/lrw.h>
Jussi Kivilinnabae6d302011-10-18 13:33:43 +030037#include <crypto/xts.h>
Jussi Kivilinna81559f92011-10-18 13:33:02 +030038
Jussi Kivilinna8280daa2011-09-26 16:47:25 +030039/* regular block cipher functions from twofish_x86_64 module */
40asmlinkage void twofish_enc_blk(struct twofish_ctx *ctx, u8 *dst,
41 const u8 *src);
42asmlinkage void twofish_dec_blk(struct twofish_ctx *ctx, u8 *dst,
43 const u8 *src);
44
45/* 3-way parallel cipher functions */
46asmlinkage void __twofish_enc_blk_3way(struct twofish_ctx *ctx, u8 *dst,
47 const u8 *src, bool xor);
48asmlinkage void twofish_dec_blk_3way(struct twofish_ctx *ctx, u8 *dst,
49 const u8 *src);
50
51static inline void twofish_enc_blk_3way(struct twofish_ctx *ctx, u8 *dst,
52 const u8 *src)
53{
54 __twofish_enc_blk_3way(ctx, dst, src, false);
55}
56
57static inline void twofish_enc_blk_xor_3way(struct twofish_ctx *ctx, u8 *dst,
58 const u8 *src)
59{
60 __twofish_enc_blk_3way(ctx, dst, src, true);
61}
62
63static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk,
64 void (*fn)(struct twofish_ctx *, u8 *, const u8 *),
65 void (*fn_3way)(struct twofish_ctx *, u8 *, const u8 *))
66{
67 struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
68 unsigned int bsize = TF_BLOCK_SIZE;
69 unsigned int nbytes;
70 int err;
71
72 err = blkcipher_walk_virt(desc, walk);
73
74 while ((nbytes = walk->nbytes)) {
75 u8 *wsrc = walk->src.virt.addr;
76 u8 *wdst = walk->dst.virt.addr;
77
78 /* Process three block batch */
79 if (nbytes >= bsize * 3) {
80 do {
81 fn_3way(ctx, wdst, wsrc);
82
83 wsrc += bsize * 3;
84 wdst += bsize * 3;
85 nbytes -= bsize * 3;
86 } while (nbytes >= bsize * 3);
87
88 if (nbytes < bsize)
89 goto done;
90 }
91
92 /* Handle leftovers */
93 do {
94 fn(ctx, wdst, wsrc);
95
96 wsrc += bsize;
97 wdst += bsize;
98 nbytes -= bsize;
99 } while (nbytes >= bsize);
100
101done:
102 err = blkcipher_walk_done(desc, walk, nbytes);
103 }
104
105 return err;
106}
107
108static int ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
109 struct scatterlist *src, unsigned int nbytes)
110{
111 struct blkcipher_walk walk;
112
113 blkcipher_walk_init(&walk, dst, src, nbytes);
114 return ecb_crypt(desc, &walk, twofish_enc_blk, twofish_enc_blk_3way);
115}
116
117static int ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
118 struct scatterlist *src, unsigned int nbytes)
119{
120 struct blkcipher_walk walk;
121
122 blkcipher_walk_init(&walk, dst, src, nbytes);
123 return ecb_crypt(desc, &walk, twofish_dec_blk, twofish_dec_blk_3way);
124}
125
126static struct crypto_alg blk_ecb_alg = {
127 .cra_name = "ecb(twofish)",
128 .cra_driver_name = "ecb-twofish-3way",
129 .cra_priority = 300,
130 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
131 .cra_blocksize = TF_BLOCK_SIZE,
132 .cra_ctxsize = sizeof(struct twofish_ctx),
133 .cra_alignmask = 0,
134 .cra_type = &crypto_blkcipher_type,
135 .cra_module = THIS_MODULE,
136 .cra_list = LIST_HEAD_INIT(blk_ecb_alg.cra_list),
137 .cra_u = {
138 .blkcipher = {
139 .min_keysize = TF_MIN_KEY_SIZE,
140 .max_keysize = TF_MAX_KEY_SIZE,
141 .setkey = twofish_setkey,
142 .encrypt = ecb_encrypt,
143 .decrypt = ecb_decrypt,
144 },
145 },
146};
147
148static unsigned int __cbc_encrypt(struct blkcipher_desc *desc,
149 struct blkcipher_walk *walk)
150{
151 struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
152 unsigned int bsize = TF_BLOCK_SIZE;
153 unsigned int nbytes = walk->nbytes;
154 u128 *src = (u128 *)walk->src.virt.addr;
155 u128 *dst = (u128 *)walk->dst.virt.addr;
156 u128 *iv = (u128 *)walk->iv;
157
158 do {
159 u128_xor(dst, src, iv);
160 twofish_enc_blk(ctx, (u8 *)dst, (u8 *)dst);
161 iv = dst;
162
163 src += 1;
164 dst += 1;
165 nbytes -= bsize;
166 } while (nbytes >= bsize);
167
168 u128_xor((u128 *)walk->iv, (u128 *)walk->iv, iv);
169 return nbytes;
170}
171
172static int cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
173 struct scatterlist *src, unsigned int nbytes)
174{
175 struct blkcipher_walk walk;
176 int err;
177
178 blkcipher_walk_init(&walk, dst, src, nbytes);
179 err = blkcipher_walk_virt(desc, &walk);
180
181 while ((nbytes = walk.nbytes)) {
182 nbytes = __cbc_encrypt(desc, &walk);
183 err = blkcipher_walk_done(desc, &walk, nbytes);
184 }
185
186 return err;
187}
188
189static unsigned int __cbc_decrypt(struct blkcipher_desc *desc,
190 struct blkcipher_walk *walk)
191{
192 struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
193 unsigned int bsize = TF_BLOCK_SIZE;
194 unsigned int nbytes = walk->nbytes;
195 u128 *src = (u128 *)walk->src.virt.addr;
196 u128 *dst = (u128 *)walk->dst.virt.addr;
197 u128 ivs[3 - 1];
198 u128 last_iv;
199
200 /* Start of the last block. */
201 src += nbytes / bsize - 1;
202 dst += nbytes / bsize - 1;
203
204 last_iv = *src;
205
206 /* Process three block batch */
207 if (nbytes >= bsize * 3) {
208 do {
209 nbytes -= bsize * (3 - 1);
210 src -= 3 - 1;
211 dst -= 3 - 1;
212
213 ivs[0] = src[0];
214 ivs[1] = src[1];
215
216 twofish_dec_blk_3way(ctx, (u8 *)dst, (u8 *)src);
217
218 u128_xor(dst + 1, dst + 1, ivs + 0);
219 u128_xor(dst + 2, dst + 2, ivs + 1);
220
221 nbytes -= bsize;
222 if (nbytes < bsize)
223 goto done;
224
225 u128_xor(dst, dst, src - 1);
226 src -= 1;
227 dst -= 1;
228 } while (nbytes >= bsize * 3);
229
230 if (nbytes < bsize)
231 goto done;
232 }
233
234 /* Handle leftovers */
235 for (;;) {
236 twofish_dec_blk(ctx, (u8 *)dst, (u8 *)src);
237
238 nbytes -= bsize;
239 if (nbytes < bsize)
240 break;
241
242 u128_xor(dst, dst, src - 1);
243 src -= 1;
244 dst -= 1;
245 }
246
247done:
248 u128_xor(dst, dst, (u128 *)walk->iv);
249 *(u128 *)walk->iv = last_iv;
250
251 return nbytes;
252}
253
254static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
255 struct scatterlist *src, unsigned int nbytes)
256{
257 struct blkcipher_walk walk;
258 int err;
259
260 blkcipher_walk_init(&walk, dst, src, nbytes);
261 err = blkcipher_walk_virt(desc, &walk);
262
263 while ((nbytes = walk.nbytes)) {
264 nbytes = __cbc_decrypt(desc, &walk);
265 err = blkcipher_walk_done(desc, &walk, nbytes);
266 }
267
268 return err;
269}
270
271static struct crypto_alg blk_cbc_alg = {
272 .cra_name = "cbc(twofish)",
273 .cra_driver_name = "cbc-twofish-3way",
274 .cra_priority = 300,
275 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
276 .cra_blocksize = TF_BLOCK_SIZE,
277 .cra_ctxsize = sizeof(struct twofish_ctx),
278 .cra_alignmask = 0,
279 .cra_type = &crypto_blkcipher_type,
280 .cra_module = THIS_MODULE,
281 .cra_list = LIST_HEAD_INIT(blk_cbc_alg.cra_list),
282 .cra_u = {
283 .blkcipher = {
284 .min_keysize = TF_MIN_KEY_SIZE,
285 .max_keysize = TF_MAX_KEY_SIZE,
286 .ivsize = TF_BLOCK_SIZE,
287 .setkey = twofish_setkey,
288 .encrypt = cbc_encrypt,
289 .decrypt = cbc_decrypt,
290 },
291 },
292};
293
294static inline void u128_to_be128(be128 *dst, const u128 *src)
295{
296 dst->a = cpu_to_be64(src->a);
297 dst->b = cpu_to_be64(src->b);
298}
299
300static inline void be128_to_u128(u128 *dst, const be128 *src)
301{
302 dst->a = be64_to_cpu(src->a);
303 dst->b = be64_to_cpu(src->b);
304}
305
306static inline void u128_inc(u128 *i)
307{
308 i->b++;
309 if (!i->b)
310 i->a++;
311}
312
313static void ctr_crypt_final(struct blkcipher_desc *desc,
314 struct blkcipher_walk *walk)
315{
316 struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
317 u8 *ctrblk = walk->iv;
318 u8 keystream[TF_BLOCK_SIZE];
319 u8 *src = walk->src.virt.addr;
320 u8 *dst = walk->dst.virt.addr;
321 unsigned int nbytes = walk->nbytes;
322
323 twofish_enc_blk(ctx, keystream, ctrblk);
324 crypto_xor(keystream, src, nbytes);
325 memcpy(dst, keystream, nbytes);
326
327 crypto_inc(ctrblk, TF_BLOCK_SIZE);
328}
329
330static unsigned int __ctr_crypt(struct blkcipher_desc *desc,
331 struct blkcipher_walk *walk)
332{
333 struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
334 unsigned int bsize = TF_BLOCK_SIZE;
335 unsigned int nbytes = walk->nbytes;
336 u128 *src = (u128 *)walk->src.virt.addr;
337 u128 *dst = (u128 *)walk->dst.virt.addr;
338 u128 ctrblk;
339 be128 ctrblocks[3];
340
341 be128_to_u128(&ctrblk, (be128 *)walk->iv);
342
343 /* Process three block batch */
344 if (nbytes >= bsize * 3) {
345 do {
346 if (dst != src) {
347 dst[0] = src[0];
348 dst[1] = src[1];
349 dst[2] = src[2];
350 }
351
352 /* create ctrblks for parallel encrypt */
353 u128_to_be128(&ctrblocks[0], &ctrblk);
354 u128_inc(&ctrblk);
355 u128_to_be128(&ctrblocks[1], &ctrblk);
356 u128_inc(&ctrblk);
357 u128_to_be128(&ctrblocks[2], &ctrblk);
358 u128_inc(&ctrblk);
359
360 twofish_enc_blk_xor_3way(ctx, (u8 *)dst,
361 (u8 *)ctrblocks);
362
363 src += 3;
364 dst += 3;
365 nbytes -= bsize * 3;
366 } while (nbytes >= bsize * 3);
367
368 if (nbytes < bsize)
369 goto done;
370 }
371
372 /* Handle leftovers */
373 do {
374 if (dst != src)
375 *dst = *src;
376
377 u128_to_be128(&ctrblocks[0], &ctrblk);
378 u128_inc(&ctrblk);
379
380 twofish_enc_blk(ctx, (u8 *)ctrblocks, (u8 *)ctrblocks);
381 u128_xor(dst, dst, (u128 *)ctrblocks);
382
383 src += 1;
384 dst += 1;
385 nbytes -= bsize;
386 } while (nbytes >= bsize);
387
388done:
389 u128_to_be128((be128 *)walk->iv, &ctrblk);
390 return nbytes;
391}
392
393static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
394 struct scatterlist *src, unsigned int nbytes)
395{
396 struct blkcipher_walk walk;
397 int err;
398
399 blkcipher_walk_init(&walk, dst, src, nbytes);
400 err = blkcipher_walk_virt_block(desc, &walk, TF_BLOCK_SIZE);
401
402 while ((nbytes = walk.nbytes) >= TF_BLOCK_SIZE) {
403 nbytes = __ctr_crypt(desc, &walk);
404 err = blkcipher_walk_done(desc, &walk, nbytes);
405 }
406
407 if (walk.nbytes) {
408 ctr_crypt_final(desc, &walk);
409 err = blkcipher_walk_done(desc, &walk, 0);
410 }
411
412 return err;
413}
414
415static struct crypto_alg blk_ctr_alg = {
416 .cra_name = "ctr(twofish)",
417 .cra_driver_name = "ctr-twofish-3way",
418 .cra_priority = 300,
419 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
Jussi Kivilinna906b2c92011-10-10 12:33:02 +0300420 .cra_blocksize = 1,
Jussi Kivilinna8280daa2011-09-26 16:47:25 +0300421 .cra_ctxsize = sizeof(struct twofish_ctx),
422 .cra_alignmask = 0,
423 .cra_type = &crypto_blkcipher_type,
424 .cra_module = THIS_MODULE,
425 .cra_list = LIST_HEAD_INIT(blk_ctr_alg.cra_list),
426 .cra_u = {
427 .blkcipher = {
428 .min_keysize = TF_MIN_KEY_SIZE,
429 .max_keysize = TF_MAX_KEY_SIZE,
430 .ivsize = TF_BLOCK_SIZE,
431 .setkey = twofish_setkey,
432 .encrypt = ctr_crypt,
433 .decrypt = ctr_crypt,
434 },
435 },
436};
437
Jussi Kivilinna81559f92011-10-18 13:33:02 +0300438static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
439{
440 const unsigned int bsize = TF_BLOCK_SIZE;
441 struct twofish_ctx *ctx = priv;
442 int i;
443
444 if (nbytes == 3 * bsize) {
445 twofish_enc_blk_3way(ctx, srcdst, srcdst);
446 return;
447 }
448
449 for (i = 0; i < nbytes / bsize; i++, srcdst += bsize)
450 twofish_enc_blk(ctx, srcdst, srcdst);
451}
452
453static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
454{
455 const unsigned int bsize = TF_BLOCK_SIZE;
456 struct twofish_ctx *ctx = priv;
457 int i;
458
459 if (nbytes == 3 * bsize) {
460 twofish_dec_blk_3way(ctx, srcdst, srcdst);
461 return;
462 }
463
464 for (i = 0; i < nbytes / bsize; i++, srcdst += bsize)
465 twofish_dec_blk(ctx, srcdst, srcdst);
466}
467
468struct twofish_lrw_ctx {
469 struct lrw_table_ctx lrw_table;
470 struct twofish_ctx twofish_ctx;
471};
472
473static int lrw_twofish_setkey(struct crypto_tfm *tfm, const u8 *key,
474 unsigned int keylen)
475{
476 struct twofish_lrw_ctx *ctx = crypto_tfm_ctx(tfm);
477 int err;
478
479 err = __twofish_setkey(&ctx->twofish_ctx, key, keylen - TF_BLOCK_SIZE,
480 &tfm->crt_flags);
481 if (err)
482 return err;
483
484 return lrw_init_table(&ctx->lrw_table, key + keylen - TF_BLOCK_SIZE);
485}
486
487static int lrw_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
488 struct scatterlist *src, unsigned int nbytes)
489{
490 struct twofish_lrw_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
491 be128 buf[3];
492 struct lrw_crypt_req req = {
493 .tbuf = buf,
494 .tbuflen = sizeof(buf),
495
496 .table_ctx = &ctx->lrw_table,
497 .crypt_ctx = &ctx->twofish_ctx,
498 .crypt_fn = encrypt_callback,
499 };
500
501 return lrw_crypt(desc, dst, src, nbytes, &req);
502}
503
504static int lrw_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
505 struct scatterlist *src, unsigned int nbytes)
506{
507 struct twofish_lrw_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
508 be128 buf[3];
509 struct lrw_crypt_req req = {
510 .tbuf = buf,
511 .tbuflen = sizeof(buf),
512
513 .table_ctx = &ctx->lrw_table,
514 .crypt_ctx = &ctx->twofish_ctx,
515 .crypt_fn = decrypt_callback,
516 };
517
518 return lrw_crypt(desc, dst, src, nbytes, &req);
519}
520
521static void lrw_exit_tfm(struct crypto_tfm *tfm)
522{
523 struct twofish_lrw_ctx *ctx = crypto_tfm_ctx(tfm);
524
525 lrw_free_table(&ctx->lrw_table);
526}
527
528static struct crypto_alg blk_lrw_alg = {
529 .cra_name = "lrw(twofish)",
530 .cra_driver_name = "lrw-twofish-3way",
531 .cra_priority = 300,
532 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
533 .cra_blocksize = TF_BLOCK_SIZE,
534 .cra_ctxsize = sizeof(struct twofish_lrw_ctx),
535 .cra_alignmask = 0,
536 .cra_type = &crypto_blkcipher_type,
537 .cra_module = THIS_MODULE,
538 .cra_list = LIST_HEAD_INIT(blk_lrw_alg.cra_list),
539 .cra_exit = lrw_exit_tfm,
540 .cra_u = {
541 .blkcipher = {
542 .min_keysize = TF_MIN_KEY_SIZE + TF_BLOCK_SIZE,
543 .max_keysize = TF_MAX_KEY_SIZE + TF_BLOCK_SIZE,
544 .ivsize = TF_BLOCK_SIZE,
545 .setkey = lrw_twofish_setkey,
546 .encrypt = lrw_encrypt,
547 .decrypt = lrw_decrypt,
548 },
549 },
550};
551
Jussi Kivilinnabae6d302011-10-18 13:33:43 +0300552struct twofish_xts_ctx {
553 struct twofish_ctx tweak_ctx;
554 struct twofish_ctx crypt_ctx;
555};
556
557static int xts_twofish_setkey(struct crypto_tfm *tfm, const u8 *key,
558 unsigned int keylen)
559{
560 struct twofish_xts_ctx *ctx = crypto_tfm_ctx(tfm);
561 u32 *flags = &tfm->crt_flags;
562 int err;
563
564 /* key consists of keys of equal size concatenated, therefore
565 * the length must be even
566 */
567 if (keylen % 2) {
568 *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
569 return -EINVAL;
570 }
571
572 /* first half of xts-key is for crypt */
573 err = __twofish_setkey(&ctx->crypt_ctx, key, keylen / 2, flags);
574 if (err)
575 return err;
576
577 /* second half of xts-key is for tweak */
578 return __twofish_setkey(&ctx->tweak_ctx, key + keylen / 2, keylen / 2,
579 flags);
580}
581
582static int xts_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
583 struct scatterlist *src, unsigned int nbytes)
584{
585 struct twofish_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
586 be128 buf[3];
587 struct xts_crypt_req req = {
588 .tbuf = buf,
589 .tbuflen = sizeof(buf),
590
591 .tweak_ctx = &ctx->tweak_ctx,
592 .tweak_fn = XTS_TWEAK_CAST(twofish_enc_blk),
593 .crypt_ctx = &ctx->crypt_ctx,
594 .crypt_fn = encrypt_callback,
595 };
596
597 return xts_crypt(desc, dst, src, nbytes, &req);
598}
599
600static int xts_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
601 struct scatterlist *src, unsigned int nbytes)
602{
603 struct twofish_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
604 be128 buf[3];
605 struct xts_crypt_req req = {
606 .tbuf = buf,
607 .tbuflen = sizeof(buf),
608
609 .tweak_ctx = &ctx->tweak_ctx,
610 .tweak_fn = XTS_TWEAK_CAST(twofish_enc_blk),
611 .crypt_ctx = &ctx->crypt_ctx,
612 .crypt_fn = decrypt_callback,
613 };
614
615 return xts_crypt(desc, dst, src, nbytes, &req);
616}
617
618static struct crypto_alg blk_xts_alg = {
619 .cra_name = "xts(twofish)",
620 .cra_driver_name = "xts-twofish-3way",
621 .cra_priority = 300,
622 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
623 .cra_blocksize = TF_BLOCK_SIZE,
624 .cra_ctxsize = sizeof(struct twofish_xts_ctx),
625 .cra_alignmask = 0,
626 .cra_type = &crypto_blkcipher_type,
627 .cra_module = THIS_MODULE,
628 .cra_list = LIST_HEAD_INIT(blk_xts_alg.cra_list),
629 .cra_u = {
630 .blkcipher = {
631 .min_keysize = TF_MIN_KEY_SIZE * 2,
632 .max_keysize = TF_MAX_KEY_SIZE * 2,
633 .ivsize = TF_BLOCK_SIZE,
634 .setkey = xts_twofish_setkey,
635 .encrypt = xts_encrypt,
636 .decrypt = xts_decrypt,
637 },
638 },
639};
640
Jussi Kivilinnaa522ee82011-12-20 12:20:16 +0200641static bool is_blacklisted_cpu(void)
642{
643 if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
644 return false;
645
646 if (boot_cpu_data.x86 == 0x06 &&
647 (boot_cpu_data.x86_model == 0x1c ||
648 boot_cpu_data.x86_model == 0x26 ||
649 boot_cpu_data.x86_model == 0x36)) {
650 /*
651 * On Atom, twofish-3way is slower than original assembler
652 * implementation. Twofish-3way trades off some performance in
653 * storing blocks in 64bit registers to allow three blocks to
654 * be processed parallel. Parallel operation then allows gaining
655 * more performance than was trade off, on out-of-order CPUs.
656 * However Atom does not benefit from this parallellism and
657 * should be blacklisted.
658 */
659 return true;
660 }
661
662 if (boot_cpu_data.x86 == 0x0f) {
663 /*
664 * On Pentium 4, twofish-3way is slower than original assembler
665 * implementation because excessive uses of 64bit rotate and
666 * left-shifts (which are really slow on P4) needed to store and
667 * handle 128bit block in two 64bit registers.
668 */
669 return true;
670 }
671
672 return false;
673}
674
675static int force;
676module_param(force, int, 0);
677MODULE_PARM_DESC(force, "Force module load, ignore CPU blacklist");
678
Jussi Kivilinna8280daa2011-09-26 16:47:25 +0300679int __init init(void)
680{
681 int err;
682
Jussi Kivilinnaa522ee82011-12-20 12:20:16 +0200683 if (!force && is_blacklisted_cpu()) {
684 printk(KERN_INFO
685 "twofish-x86_64-3way: performance on this CPU "
686 "would be suboptimal: disabling "
687 "twofish-x86_64-3way.\n");
688 return -ENODEV;
689 }
690
Jussi Kivilinna8280daa2011-09-26 16:47:25 +0300691 err = crypto_register_alg(&blk_ecb_alg);
692 if (err)
693 goto ecb_err;
694 err = crypto_register_alg(&blk_cbc_alg);
695 if (err)
696 goto cbc_err;
697 err = crypto_register_alg(&blk_ctr_alg);
698 if (err)
699 goto ctr_err;
Jussi Kivilinna81559f92011-10-18 13:33:02 +0300700 err = crypto_register_alg(&blk_lrw_alg);
701 if (err)
702 goto blk_lrw_err;
Jussi Kivilinnabae6d302011-10-18 13:33:43 +0300703 err = crypto_register_alg(&blk_xts_alg);
704 if (err)
705 goto blk_xts_err;
Jussi Kivilinna8280daa2011-09-26 16:47:25 +0300706
707 return 0;
708
Jussi Kivilinnabae6d302011-10-18 13:33:43 +0300709 crypto_unregister_alg(&blk_xts_alg);
710blk_xts_err:
Jussi Kivilinnabae6d302011-10-18 13:33:43 +0300711 crypto_unregister_alg(&blk_lrw_alg);
712blk_lrw_err:
Jussi Kivilinnabae6d302011-10-18 13:33:43 +0300713 crypto_unregister_alg(&blk_ctr_alg);
Jussi Kivilinna8280daa2011-09-26 16:47:25 +0300714ctr_err:
715 crypto_unregister_alg(&blk_cbc_alg);
716cbc_err:
717 crypto_unregister_alg(&blk_ecb_alg);
718ecb_err:
719 return err;
720}
721
722void __exit fini(void)
723{
Jussi Kivilinnabae6d302011-10-18 13:33:43 +0300724 crypto_unregister_alg(&blk_xts_alg);
Jussi Kivilinna81559f92011-10-18 13:33:02 +0300725 crypto_unregister_alg(&blk_lrw_alg);
Jussi Kivilinna8280daa2011-09-26 16:47:25 +0300726 crypto_unregister_alg(&blk_ctr_alg);
727 crypto_unregister_alg(&blk_cbc_alg);
728 crypto_unregister_alg(&blk_ecb_alg);
729}
730
731module_init(init);
732module_exit(fini);
733
734MODULE_LICENSE("GPL");
735MODULE_DESCRIPTION("Twofish Cipher Algorithm, 3-way parallel asm optimized");
736MODULE_ALIAS("twofish");
737MODULE_ALIAS("twofish-asm");