Pileus Git - ~andy/linux/blob - arch/x86/crypto/twofish_glue_3way.c

   1 /*
   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
  28 #include <linux/crypto.h>
  29 #include <linux/init.h>
  30 #include <linux/module.h>
  31 #include <linux/types.h>
  32 #include <crypto/algapi.h>
  33 #include <crypto/twofish.h>
  34 #include <crypto/b128ops.h>
  35 #include <crypto/lrw.h>
  36 #include <crypto/xts.h>
  37
  38 /* regular block cipher functions from twofish_x86_64 module */
  39 asmlinkage void twofish_enc_blk(struct twofish_ctx *ctx, u8 *dst,
  40                                 const u8 *src);
  41 asmlinkage void twofish_dec_blk(struct twofish_ctx *ctx, u8 *dst,
  42                                 const u8 *src);
  43
  44 /* 3-way parallel cipher functions */
  45 asmlinkage void __twofish_enc_blk_3way(struct twofish_ctx *ctx, u8 *dst,
  46                                        const u8 *src, bool xor);
  47 asmlinkage void twofish_dec_blk_3way(struct twofish_ctx *ctx, u8 *dst,
  48                                      const u8 *src);
  49
  50 static inline void twofish_enc_blk_3way(struct twofish_ctx *ctx, u8 *dst,
  51                                         const u8 *src)
  52 {
  53         __twofish_enc_blk_3way(ctx, dst, src, false);
  54 }
  55
  56 static inline void twofish_enc_blk_xor_3way(struct twofish_ctx *ctx, u8 *dst,
  57                                             const u8 *src)
  58 {
  59         __twofish_enc_blk_3way(ctx, dst, src, true);
  60 }
  61
  62 static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk,
  63                      void (*fn)(struct twofish_ctx *, u8 *, const u8 *),
  64                      void (*fn_3way)(struct twofish_ctx *, u8 *, const u8 *))
  65 {
  66         struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
  67         unsigned int bsize = TF_BLOCK_SIZE;
  68         unsigned int nbytes;
  69         int err;
  70
  71         err = blkcipher_walk_virt(desc, walk);
  72
  73         while ((nbytes = walk->nbytes)) {
  74                 u8 *wsrc = walk->src.virt.addr;
  75                 u8 *wdst = walk->dst.virt.addr;
  76
  77                 /* Process three block batch */
  78                 if (nbytes >= bsize * 3) {
  79                         do {
  80                                 fn_3way(ctx, wdst, wsrc);
  81
  82                                 wsrc += bsize * 3;
  83                                 wdst += bsize * 3;
  84                                 nbytes -= bsize * 3;
  85                         } while (nbytes >= bsize * 3);
  86
  87                         if (nbytes < bsize)
  88                                 goto done;
  89                 }
  90
  91                 /* Handle leftovers */
  92                 do {
  93                         fn(ctx, wdst, wsrc);
  94
  95                         wsrc += bsize;
  96                         wdst += bsize;
  97                         nbytes -= bsize;
  98                 } while (nbytes >= bsize);
  99
 100 done:
 101                 err = blkcipher_walk_done(desc, walk, nbytes);
 102         }
 103
 104         return err;
 105 }
 106
 107 static int ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 108                        struct scatterlist *src, unsigned int nbytes)
 109 {
 110         struct blkcipher_walk walk;
 111
 112         blkcipher_walk_init(&walk, dst, src, nbytes);
 113         return ecb_crypt(desc, &walk, twofish_enc_blk, twofish_enc_blk_3way);
 114 }
 115
 116 static int ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 117                        struct scatterlist *src, unsigned int nbytes)
 118 {
 119         struct blkcipher_walk walk;
 120
 121         blkcipher_walk_init(&walk, dst, src, nbytes);
 122         return ecb_crypt(desc, &walk, twofish_dec_blk, twofish_dec_blk_3way);
 123 }
 124
 125 static struct crypto_alg blk_ecb_alg = {
 126         .cra_name               = "ecb(twofish)",
 127         .cra_driver_name        = "ecb-twofish-3way",
 128         .cra_priority           = 300,
 129         .cra_flags              = CRYPTO_ALG_TYPE_BLKCIPHER,
 130         .cra_blocksize          = TF_BLOCK_SIZE,
 131         .cra_ctxsize            = sizeof(struct twofish_ctx),
 132         .cra_alignmask          = 0,
 133         .cra_type               = &crypto_blkcipher_type,
 134         .cra_module             = THIS_MODULE,
 135         .cra_list               = LIST_HEAD_INIT(blk_ecb_alg.cra_list),
 136         .cra_u = {
 137                 .blkcipher = {
 138                         .min_keysize    = TF_MIN_KEY_SIZE,
 139                         .max_keysize    = TF_MAX_KEY_SIZE,
 140                         .setkey         = twofish_setkey,
 141                         .encrypt        = ecb_encrypt,
 142                         .decrypt        = ecb_decrypt,
 143                 },
 144         },
 145 };
 146
 147 static unsigned int __cbc_encrypt(struct blkcipher_desc *desc,
 148                                   struct blkcipher_walk *walk)
 149 {
 150         struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 151         unsigned int bsize = TF_BLOCK_SIZE;
 152         unsigned int nbytes = walk->nbytes;
 153         u128 *src = (u128 *)walk->src.virt.addr;
 154         u128 *dst = (u128 *)walk->dst.virt.addr;
 155         u128 *iv = (u128 *)walk->iv;
 156
 157         do {
 158                 u128_xor(dst, src, iv);
 159                 twofish_enc_blk(ctx, (u8 *)dst, (u8 *)dst);
 160                 iv = dst;
 161
 162                 src += 1;
 163                 dst += 1;
 164                 nbytes -= bsize;
 165         } while (nbytes >= bsize);
 166
 167         u128_xor((u128 *)walk->iv, (u128 *)walk->iv, iv);
 168         return nbytes;
 169 }
 170
 171 static int cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 172                        struct scatterlist *src, unsigned int nbytes)
 173 {
 174         struct blkcipher_walk walk;
 175         int err;
 176
 177         blkcipher_walk_init(&walk, dst, src, nbytes);
 178         err = blkcipher_walk_virt(desc, &walk);
 179
 180         while ((nbytes = walk.nbytes)) {
 181                 nbytes = __cbc_encrypt(desc, &walk);
 182                 err = blkcipher_walk_done(desc, &walk, nbytes);
 183         }
 184
 185         return err;
 186 }
 187
 188 static unsigned int __cbc_decrypt(struct blkcipher_desc *desc,
 189                                   struct blkcipher_walk *walk)
 190 {
 191         struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 192         unsigned int bsize = TF_BLOCK_SIZE;
 193         unsigned int nbytes = walk->nbytes;
 194         u128 *src = (u128 *)walk->src.virt.addr;
 195         u128 *dst = (u128 *)walk->dst.virt.addr;
 196         u128 ivs[3 - 1];
 197         u128 last_iv;
 198
 199         /* Start of the last block. */
 200         src += nbytes / bsize - 1;
 201         dst += nbytes / bsize - 1;
 202
 203         last_iv = *src;
 204
 205         /* Process three block batch */
 206         if (nbytes >= bsize * 3) {
 207                 do {
 208                         nbytes -= bsize * (3 - 1);
 209                         src -= 3 - 1;
 210                         dst -= 3 - 1;
 211
 212                         ivs[0] = src[0];
 213                         ivs[1] = src[1];
 214
 215                         twofish_dec_blk_3way(ctx, (u8 *)dst, (u8 *)src);
 216
 217                         u128_xor(dst + 1, dst + 1, ivs + 0);
 218                         u128_xor(dst + 2, dst + 2, ivs + 1);
 219
 220                         nbytes -= bsize;
 221                         if (nbytes < bsize)
 222                                 goto done;
 223
 224                         u128_xor(dst, dst, src - 1);
 225                         src -= 1;
 226                         dst -= 1;
 227                 } while (nbytes >= bsize * 3);
 228
 229                 if (nbytes < bsize)
 230                         goto done;
 231         }
 232
 233         /* Handle leftovers */
 234         for (;;) {
 235                 twofish_dec_blk(ctx, (u8 *)dst, (u8 *)src);
 236
 237                 nbytes -= bsize;
 238                 if (nbytes < bsize)
 239                         break;
 240
 241                 u128_xor(dst, dst, src - 1);
 242                 src -= 1;
 243                 dst -= 1;
 244         }
 245
 246 done:
 247         u128_xor(dst, dst, (u128 *)walk->iv);
 248         *(u128 *)walk->iv = last_iv;
 249
 250         return nbytes;
 251 }
 252
 253 static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 254                        struct scatterlist *src, unsigned int nbytes)
 255 {
 256         struct blkcipher_walk walk;
 257         int err;
 258
 259         blkcipher_walk_init(&walk, dst, src, nbytes);
 260         err = blkcipher_walk_virt(desc, &walk);
 261
 262         while ((nbytes = walk.nbytes)) {
 263                 nbytes = __cbc_decrypt(desc, &walk);
 264                 err = blkcipher_walk_done(desc, &walk, nbytes);
 265         }
 266
 267         return err;
 268 }
 269
 270 static struct crypto_alg blk_cbc_alg = {
 271         .cra_name               = "cbc(twofish)",
 272         .cra_driver_name        = "cbc-twofish-3way",
 273         .cra_priority           = 300,
 274         .cra_flags              = CRYPTO_ALG_TYPE_BLKCIPHER,
 275         .cra_blocksize          = TF_BLOCK_SIZE,
 276         .cra_ctxsize            = sizeof(struct twofish_ctx),
 277         .cra_alignmask          = 0,
 278         .cra_type               = &crypto_blkcipher_type,
 279         .cra_module             = THIS_MODULE,
 280         .cra_list               = LIST_HEAD_INIT(blk_cbc_alg.cra_list),
 281         .cra_u = {
 282                 .blkcipher = {
 283                         .min_keysize    = TF_MIN_KEY_SIZE,
 284                         .max_keysize    = TF_MAX_KEY_SIZE,
 285                         .ivsize         = TF_BLOCK_SIZE,
 286                         .setkey         = twofish_setkey,
 287                         .encrypt        = cbc_encrypt,
 288                         .decrypt        = cbc_decrypt,
 289                 },
 290         },
 291 };
 292
 293 static inline void u128_to_be128(be128 *dst, const u128 *src)
 294 {
 295         dst->a = cpu_to_be64(src->a);
 296         dst->b = cpu_to_be64(src->b);
 297 }
 298
 299 static inline void be128_to_u128(u128 *dst, const be128 *src)
 300 {
 301         dst->a = be64_to_cpu(src->a);
 302         dst->b = be64_to_cpu(src->b);
 303 }
 304
 305 static inline void u128_inc(u128 *i)
 306 {
 307         i->b++;
 308         if (!i->b)
 309                 i->a++;
 310 }
 311
 312 static void ctr_crypt_final(struct blkcipher_desc *desc,
 313                             struct blkcipher_walk *walk)
 314 {
 315         struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 316         u8 *ctrblk = walk->iv;
 317         u8 keystream[TF_BLOCK_SIZE];
 318         u8 *src = walk->src.virt.addr;
 319         u8 *dst = walk->dst.virt.addr;
 320         unsigned int nbytes = walk->nbytes;
 321
 322         twofish_enc_blk(ctx, keystream, ctrblk);
 323         crypto_xor(keystream, src, nbytes);
 324         memcpy(dst, keystream, nbytes);
 325
 326         crypto_inc(ctrblk, TF_BLOCK_SIZE);
 327 }
 328
 329 static unsigned int __ctr_crypt(struct blkcipher_desc *desc,
 330                                 struct blkcipher_walk *walk)
 331 {
 332         struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 333         unsigned int bsize = TF_BLOCK_SIZE;
 334         unsigned int nbytes = walk->nbytes;
 335         u128 *src = (u128 *)walk->src.virt.addr;
 336         u128 *dst = (u128 *)walk->dst.virt.addr;
 337         u128 ctrblk;
 338         be128 ctrblocks[3];
 339
 340         be128_to_u128(&ctrblk, (be128 *)walk->iv);
 341
 342         /* Process three block batch */
 343         if (nbytes >= bsize * 3) {
 344                 do {
 345                         if (dst != src) {
 346                                 dst[0] = src[0];
 347                                 dst[1] = src[1];
 348                                 dst[2] = src[2];
 349                         }
 350
 351                         /* create ctrblks for parallel encrypt */
 352                         u128_to_be128(&ctrblocks[0], &ctrblk);
 353                         u128_inc(&ctrblk);
 354                         u128_to_be128(&ctrblocks[1], &ctrblk);
 355                         u128_inc(&ctrblk);
 356                         u128_to_be128(&ctrblocks[2], &ctrblk);
 357                         u128_inc(&ctrblk);
 358
 359                         twofish_enc_blk_xor_3way(ctx, (u8 *)dst,
 360                                                  (u8 *)ctrblocks);
 361
 362                         src += 3;
 363                         dst += 3;
 364                         nbytes -= bsize * 3;
 365                 } while (nbytes >= bsize * 3);
 366
 367                 if (nbytes < bsize)
 368                         goto done;
 369         }
 370
 371         /* Handle leftovers */
 372         do {
 373                 if (dst != src)
 374                         *dst = *src;
 375
 376                 u128_to_be128(&ctrblocks[0], &ctrblk);
 377                 u128_inc(&ctrblk);
 378
 379                 twofish_enc_blk(ctx, (u8 *)ctrblocks, (u8 *)ctrblocks);
 380                 u128_xor(dst, dst, (u128 *)ctrblocks);
 381
 382                 src += 1;
 383                 dst += 1;
 384                 nbytes -= bsize;
 385         } while (nbytes >= bsize);
 386
 387 done:
 388         u128_to_be128((be128 *)walk->iv, &ctrblk);
 389         return nbytes;
 390 }
 391
 392 static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 393                      struct scatterlist *src, unsigned int nbytes)
 394 {
 395         struct blkcipher_walk walk;
 396         int err;
 397
 398         blkcipher_walk_init(&walk, dst, src, nbytes);
 399         err = blkcipher_walk_virt_block(desc, &walk, TF_BLOCK_SIZE);
 400
 401         while ((nbytes = walk.nbytes) >= TF_BLOCK_SIZE) {
 402                 nbytes = __ctr_crypt(desc, &walk);
 403                 err = blkcipher_walk_done(desc, &walk, nbytes);
 404         }
 405
 406         if (walk.nbytes) {
 407                 ctr_crypt_final(desc, &walk);
 408                 err = blkcipher_walk_done(desc, &walk, 0);
 409         }
 410
 411         return err;
 412 }
 413
 414 static struct crypto_alg blk_ctr_alg = {
 415         .cra_name               = "ctr(twofish)",
 416         .cra_driver_name        = "ctr-twofish-3way",
 417         .cra_priority           = 300,
 418         .cra_flags              = CRYPTO_ALG_TYPE_BLKCIPHER,
 419         .cra_blocksize          = 1,
 420         .cra_ctxsize            = sizeof(struct twofish_ctx),
 421         .cra_alignmask          = 0,
 422         .cra_type               = &crypto_blkcipher_type,
 423         .cra_module             = THIS_MODULE,
 424         .cra_list               = LIST_HEAD_INIT(blk_ctr_alg.cra_list),
 425         .cra_u = {
 426                 .blkcipher = {
 427                         .min_keysize    = TF_MIN_KEY_SIZE,
 428                         .max_keysize    = TF_MAX_KEY_SIZE,
 429                         .ivsize         = TF_BLOCK_SIZE,
 430                         .setkey         = twofish_setkey,
 431                         .encrypt        = ctr_crypt,
 432                         .decrypt        = ctr_crypt,
 433                 },
 434         },
 435 };
 436
 437 static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
 438 {
 439         const unsigned int bsize = TF_BLOCK_SIZE;
 440         struct twofish_ctx *ctx = priv;
 441         int i;
 442
 443         if (nbytes == 3 * bsize) {
 444                 twofish_enc_blk_3way(ctx, srcdst, srcdst);
 445                 return;
 446         }
 447
 448         for (i = 0; i < nbytes / bsize; i++, srcdst += bsize)
 449                 twofish_enc_blk(ctx, srcdst, srcdst);
 450 }
 451
 452 static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
 453 {
 454         const unsigned int bsize = TF_BLOCK_SIZE;
 455         struct twofish_ctx *ctx = priv;
 456         int i;
 457
 458         if (nbytes == 3 * bsize) {
 459                 twofish_dec_blk_3way(ctx, srcdst, srcdst);
 460                 return;
 461         }
 462
 463         for (i = 0; i < nbytes / bsize; i++, srcdst += bsize)
 464                 twofish_dec_blk(ctx, srcdst, srcdst);
 465 }
 466
 467 struct twofish_lrw_ctx {
 468         struct lrw_table_ctx lrw_table;
 469         struct twofish_ctx twofish_ctx;
 470 };
 471
 472 static int lrw_twofish_setkey(struct crypto_tfm *tfm, const u8 *key,
 473                               unsigned int keylen)
 474 {
 475         struct twofish_lrw_ctx *ctx = crypto_tfm_ctx(tfm);
 476         int err;
 477
 478         err = __twofish_setkey(&ctx->twofish_ctx, key, keylen - TF_BLOCK_SIZE,
 479                                &tfm->crt_flags);
 480         if (err)
 481                 return err;
 482
 483         return lrw_init_table(&ctx->lrw_table, key + keylen - TF_BLOCK_SIZE);
 484 }
 485
 486 static int lrw_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 487                        struct scatterlist *src, unsigned int nbytes)
 488 {
 489         struct twofish_lrw_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 490         be128 buf[3];
 491         struct lrw_crypt_req req = {
 492                 .tbuf = buf,
 493                 .tbuflen = sizeof(buf),
 494
 495                 .table_ctx = &ctx->lrw_table,
 496                 .crypt_ctx = &ctx->twofish_ctx,
 497                 .crypt_fn = encrypt_callback,
 498         };
 499
 500         return lrw_crypt(desc, dst, src, nbytes, &req);
 501 }
 502
 503 static int lrw_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 504                        struct scatterlist *src, unsigned int nbytes)
 505 {
 506         struct twofish_lrw_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 507         be128 buf[3];
 508         struct lrw_crypt_req req = {
 509                 .tbuf = buf,
 510                 .tbuflen = sizeof(buf),
 511
 512                 .table_ctx = &ctx->lrw_table,
 513                 .crypt_ctx = &ctx->twofish_ctx,
 514                 .crypt_fn = decrypt_callback,
 515         };
 516
 517         return lrw_crypt(desc, dst, src, nbytes, &req);
 518 }
 519
 520 static void lrw_exit_tfm(struct crypto_tfm *tfm)
 521 {
 522         struct twofish_lrw_ctx *ctx = crypto_tfm_ctx(tfm);
 523
 524         lrw_free_table(&ctx->lrw_table);
 525 }
 526
 527 static struct crypto_alg blk_lrw_alg = {
 528         .cra_name               = "lrw(twofish)",
 529         .cra_driver_name        = "lrw-twofish-3way",
 530         .cra_priority           = 300,
 531         .cra_flags              = CRYPTO_ALG_TYPE_BLKCIPHER,
 532         .cra_blocksize          = TF_BLOCK_SIZE,
 533         .cra_ctxsize            = sizeof(struct twofish_lrw_ctx),
 534         .cra_alignmask          = 0,
 535         .cra_type               = &crypto_blkcipher_type,
 536         .cra_module             = THIS_MODULE,
 537         .cra_list               = LIST_HEAD_INIT(blk_lrw_alg.cra_list),
 538         .cra_exit               = lrw_exit_tfm,
 539         .cra_u = {
 540                 .blkcipher = {
 541                         .min_keysize    = TF_MIN_KEY_SIZE + TF_BLOCK_SIZE,
 542                         .max_keysize    = TF_MAX_KEY_SIZE + TF_BLOCK_SIZE,
 543                         .ivsize         = TF_BLOCK_SIZE,
 544                         .setkey         = lrw_twofish_setkey,
 545                         .encrypt        = lrw_encrypt,
 546                         .decrypt        = lrw_decrypt,
 547                 },
 548         },
 549 };
 550
 551 struct twofish_xts_ctx {
 552         struct twofish_ctx tweak_ctx;
 553         struct twofish_ctx crypt_ctx;
 554 };
 555
 556 static int xts_twofish_setkey(struct crypto_tfm *tfm, const u8 *key,
 557                               unsigned int keylen)
 558 {
 559         struct twofish_xts_ctx *ctx = crypto_tfm_ctx(tfm);
 560         u32 *flags = &tfm->crt_flags;
 561         int err;
 562
 563         /* key consists of keys of equal size concatenated, therefore
 564          * the length must be even
 565          */
 566         if (keylen % 2) {
 567                 *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
 568                 return -EINVAL;
 569         }
 570
 571         /* first half of xts-key is for crypt */
 572         err = __twofish_setkey(&ctx->crypt_ctx, key, keylen / 2, flags);
 573         if (err)
 574                 return err;
 575
 576         /* second half of xts-key is for tweak */
 577         return __twofish_setkey(&ctx->tweak_ctx, key + keylen / 2, keylen / 2,
 578                                 flags);
 579 }
 580
 581 static int xts_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 582                        struct scatterlist *src, unsigned int nbytes)
 583 {
 584         struct twofish_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 585         be128 buf[3];
 586         struct xts_crypt_req req = {
 587                 .tbuf = buf,
 588                 .tbuflen = sizeof(buf),
 589
 590                 .tweak_ctx = &ctx->tweak_ctx,
 591                 .tweak_fn = XTS_TWEAK_CAST(twofish_enc_blk),
 592                 .crypt_ctx = &ctx->crypt_ctx,
 593                 .crypt_fn = encrypt_callback,
 594         };
 595
 596         return xts_crypt(desc, dst, src, nbytes, &req);
 597 }
 598
 599 static int xts_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 600                        struct scatterlist *src, unsigned int nbytes)
 601 {
 602         struct twofish_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 603         be128 buf[3];
 604         struct xts_crypt_req req = {
 605                 .tbuf = buf,
 606                 .tbuflen = sizeof(buf),
 607
 608                 .tweak_ctx = &ctx->tweak_ctx,
 609                 .tweak_fn = XTS_TWEAK_CAST(twofish_enc_blk),
 610                 .crypt_ctx = &ctx->crypt_ctx,
 611                 .crypt_fn = decrypt_callback,
 612         };
 613
 614         return xts_crypt(desc, dst, src, nbytes, &req);
 615 }
 616
 617 static struct crypto_alg blk_xts_alg = {
 618         .cra_name               = "xts(twofish)",
 619         .cra_driver_name        = "xts-twofish-3way",
 620         .cra_priority           = 300,
 621         .cra_flags              = CRYPTO_ALG_TYPE_BLKCIPHER,
 622         .cra_blocksize          = TF_BLOCK_SIZE,
 623         .cra_ctxsize            = sizeof(struct twofish_xts_ctx),
 624         .cra_alignmask          = 0,
 625         .cra_type               = &crypto_blkcipher_type,
 626         .cra_module             = THIS_MODULE,
 627         .cra_list               = LIST_HEAD_INIT(blk_xts_alg.cra_list),
 628         .cra_u = {
 629                 .blkcipher = {
 630                         .min_keysize    = TF_MIN_KEY_SIZE * 2,
 631                         .max_keysize    = TF_MAX_KEY_SIZE * 2,
 632                         .ivsize         = TF_BLOCK_SIZE,
 633                         .setkey         = xts_twofish_setkey,
 634                         .encrypt        = xts_encrypt,
 635                         .decrypt        = xts_decrypt,
 636                 },
 637         },
 638 };
 639
 640 int __init init(void)
 641 {
 642         int err;
 643
 644         err = crypto_register_alg(&blk_ecb_alg);
 645         if (err)
 646                 goto ecb_err;
 647         err = crypto_register_alg(&blk_cbc_alg);
 648         if (err)
 649                 goto cbc_err;
 650         err = crypto_register_alg(&blk_ctr_alg);
 651         if (err)
 652                 goto ctr_err;
 653         err = crypto_register_alg(&blk_lrw_alg);
 654         if (err)
 655                 goto blk_lrw_err;
 656         err = crypto_register_alg(&blk_xts_alg);
 657         if (err)
 658                 goto blk_xts_err;
 659
 660         return 0;
 661
 662         crypto_unregister_alg(&blk_xts_alg);
 663 blk_xts_err:
 664         crypto_unregister_alg(&blk_lrw_alg);
 665 blk_lrw_err:
 666         crypto_unregister_alg(&blk_ctr_alg);
 667 ctr_err:
 668         crypto_unregister_alg(&blk_cbc_alg);
 669 cbc_err:
 670         crypto_unregister_alg(&blk_ecb_alg);
 671 ecb_err:
 672         return err;
 673 }
 674
 675 void __exit fini(void)
 676 {
 677         crypto_unregister_alg(&blk_xts_alg);
 678         crypto_unregister_alg(&blk_lrw_alg);
 679         crypto_unregister_alg(&blk_ctr_alg);
 680         crypto_unregister_alg(&blk_cbc_alg);
 681         crypto_unregister_alg(&blk_ecb_alg);
 682 }
 683
 684 module_init(init);
 685 module_exit(fini);
 686
 687 MODULE_LICENSE("GPL");
 688 MODULE_DESCRIPTION("Twofish Cipher Algorithm, 3-way parallel asm optimized");
 689 MODULE_ALIAS("twofish");
 690 MODULE_ALIAS("twofish-asm");