arch/x86/crypto/des3_ede_glue.c

   1 /*
   2  * Glue Code for assembler optimized version of 3DES
   3  *
   4  * Copyright © 2014 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  */
  22
  23 #include <asm/processor.h>
  24 #include <crypto/des.h>
  25 #include <linux/crypto.h>
  26 #include <linux/init.h>
  27 #include <linux/module.h>
  28 #include <linux/types.h>
  29 #include <crypto/algapi.h>
  30
  31 struct des3_ede_x86_ctx {
  32         u32 enc_expkey[DES3_EDE_EXPKEY_WORDS];
  33         u32 dec_expkey[DES3_EDE_EXPKEY_WORDS];
  34 };
  35
  36 /* regular block cipher functions */
  37 asmlinkage void des3_ede_x86_64_crypt_blk(const u32 *expkey, u8 *dst,
  38                                           const u8 *src);
  39
  40 /* 3-way parallel cipher functions */
  41 asmlinkage void des3_ede_x86_64_crypt_blk_3way(const u32 *expkey, u8 *dst,
  42                                                const u8 *src);
  43
  44 static inline void des3_ede_enc_blk(struct des3_ede_x86_ctx *ctx, u8 *dst,
  45                                     const u8 *src)
  46 {
  47         u32 *enc_ctx = ctx->enc_expkey;
  48
  49         des3_ede_x86_64_crypt_blk(enc_ctx, dst, src);
  50 }
  51
  52 static inline void des3_ede_dec_blk(struct des3_ede_x86_ctx *ctx, u8 *dst,
  53                                     const u8 *src)
  54 {
  55         u32 *dec_ctx = ctx->dec_expkey;
  56
  57         des3_ede_x86_64_crypt_blk(dec_ctx, dst, src);
  58 }
  59
  60 static inline void des3_ede_enc_blk_3way(struct des3_ede_x86_ctx *ctx, u8 *dst,
  61                                          const u8 *src)
  62 {
  63         u32 *enc_ctx = ctx->enc_expkey;
  64
  65         des3_ede_x86_64_crypt_blk_3way(enc_ctx, dst, src);
  66 }
  67
  68 static inline void des3_ede_dec_blk_3way(struct des3_ede_x86_ctx *ctx, u8 *dst,
  69                                          const u8 *src)
  70 {
  71         u32 *dec_ctx = ctx->dec_expkey;
  72
  73         des3_ede_x86_64_crypt_blk_3way(dec_ctx, dst, src);
  74 }
  75
  76 static void des3_ede_x86_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
  77 {
  78         des3_ede_enc_blk(crypto_tfm_ctx(tfm), dst, src);
  79 }
  80
  81 static void des3_ede_x86_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
  82 {
  83         des3_ede_dec_blk(crypto_tfm_ctx(tfm), dst, src);
  84 }
  85
  86 static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk,
  87                      const u32 *expkey)
  88 {
  89         unsigned int bsize = DES3_EDE_BLOCK_SIZE;
  90         unsigned int nbytes;
  91         int err;
  92
  93         err = blkcipher_walk_virt(desc, walk);
  94
  95         while ((nbytes = walk->nbytes)) {
  96                 u8 *wsrc = walk->src.virt.addr;
  97                 u8 *wdst = walk->dst.virt.addr;
  98
  99                 /* Process four block batch */
 100                 if (nbytes >= bsize * 3) {
 101                         do {
 102                                 des3_ede_x86_64_crypt_blk_3way(expkey, wdst,
 103                                                                wsrc);
 104
 105                                 wsrc += bsize * 3;
 106                                 wdst += bsize * 3;
 107                                 nbytes -= bsize * 3;
 108                         } while (nbytes >= bsize * 3);
 109
 110                         if (nbytes < bsize)
 111                                 goto done;
 112                 }
 113
 114                 /* Handle leftovers */
 115                 do {
 116                         des3_ede_x86_64_crypt_blk(expkey, wdst, wsrc);
 117
 118                         wsrc += bsize;
 119                         wdst += bsize;
 120                         nbytes -= bsize;
 121                 } while (nbytes >= bsize);
 122
 123 done:
 124                 err = blkcipher_walk_done(desc, walk, nbytes);
 125         }
 126
 127         return err;
 128 }
 129
 130 static int ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 131                        struct scatterlist *src, unsigned int nbytes)
 132 {
 133         struct des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 134         struct blkcipher_walk walk;
 135
 136         blkcipher_walk_init(&walk, dst, src, nbytes);
 137         return ecb_crypt(desc, &walk, ctx->enc_expkey);
 138 }
 139
 140 static int ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 141                        struct scatterlist *src, unsigned int nbytes)
 142 {
 143         struct des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 144         struct blkcipher_walk walk;
 145
 146         blkcipher_walk_init(&walk, dst, src, nbytes);
 147         return ecb_crypt(desc, &walk, ctx->dec_expkey);
 148 }
 149
 150 static unsigned int __cbc_encrypt(struct blkcipher_desc *desc,
 151                                   struct blkcipher_walk *walk)
 152 {
 153         struct des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 154         unsigned int bsize = DES3_EDE_BLOCK_SIZE;
 155         unsigned int nbytes = walk->nbytes;
 156         u64 *src = (u64 *)walk->src.virt.addr;
 157         u64 *dst = (u64 *)walk->dst.virt.addr;
 158         u64 *iv = (u64 *)walk->iv;
 159
 160         do {
 161                 *dst = *src ^ *iv;
 162                 des3_ede_enc_blk(ctx, (u8 *)dst, (u8 *)dst);
 163                 iv = dst;
 164
 165                 src += 1;
 166                 dst += 1;
 167                 nbytes -= bsize;
 168         } while (nbytes >= bsize);
 169
 170         *(u64 *)walk->iv = *iv;
 171         return nbytes;
 172 }
 173
 174 static int cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 175                        struct scatterlist *src, unsigned int nbytes)
 176 {
 177         struct blkcipher_walk walk;
 178         int err;
 179
 180         blkcipher_walk_init(&walk, dst, src, nbytes);
 181         err = blkcipher_walk_virt(desc, &walk);
 182
 183         while ((nbytes = walk.nbytes)) {
 184                 nbytes = __cbc_encrypt(desc, &walk);
 185                 err = blkcipher_walk_done(desc, &walk, nbytes);
 186         }
 187
 188         return err;
 189 }
 190
 191 static unsigned int __cbc_decrypt(struct blkcipher_desc *desc,
 192                                   struct blkcipher_walk *walk)
 193 {
 194         struct des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 195         unsigned int bsize = DES3_EDE_BLOCK_SIZE;
 196         unsigned int nbytes = walk->nbytes;
 197         u64 *src = (u64 *)walk->src.virt.addr;
 198         u64 *dst = (u64 *)walk->dst.virt.addr;
 199         u64 ivs[3 - 1];
 200         u64 last_iv;
 201
 202         /* Start of the last block. */
 203         src += nbytes / bsize - 1;
 204         dst += nbytes / bsize - 1;
 205
 206         last_iv = *src;
 207
 208         /* Process four block batch */
 209         if (nbytes >= bsize * 3) {
 210                 do {
 211                         nbytes -= bsize * 3 - bsize;
 212                         src -= 3 - 1;
 213                         dst -= 3 - 1;
 214
 215                         ivs[0] = src[0];
 216                         ivs[1] = src[1];
 217
 218                         des3_ede_dec_blk_3way(ctx, (u8 *)dst, (u8 *)src);
 219
 220                         dst[1] ^= ivs[0];
 221                         dst[2] ^= ivs[1];
 222
 223                         nbytes -= bsize;
 224                         if (nbytes < bsize)
 225                                 goto done;
 226
 227                         *dst ^= *(src - 1);
 228                         src -= 1;
 229                         dst -= 1;
 230                 } while (nbytes >= bsize * 3);
 231         }
 232
 233         /* Handle leftovers */
 234         for (;;) {
 235                 des3_ede_dec_blk(ctx, (u8 *)dst, (u8 *)src);
 236
 237                 nbytes -= bsize;
 238                 if (nbytes < bsize)
 239                         break;
 240
 241                 *dst ^= *(src - 1);
 242                 src -= 1;
 243                 dst -= 1;
 244         }
 245
 246 done:
 247         *dst ^= *(u64 *)walk->iv;
 248         *(u64 *)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 void ctr_crypt_final(struct des3_ede_x86_ctx *ctx,
 271                             struct blkcipher_walk *walk)
 272 {
 273         u8 *ctrblk = walk->iv;
 274         u8 keystream[DES3_EDE_BLOCK_SIZE];
 275         u8 *src = walk->src.virt.addr;
 276         u8 *dst = walk->dst.virt.addr;
 277         unsigned int nbytes = walk->nbytes;
 278
 279         des3_ede_enc_blk(ctx, keystream, ctrblk);
 280         crypto_xor_cpy(dst, keystream, src, nbytes);
 281
 282         crypto_inc(ctrblk, DES3_EDE_BLOCK_SIZE);
 283 }
 284
 285 static unsigned int __ctr_crypt(struct blkcipher_desc *desc,
 286                                 struct blkcipher_walk *walk)
 287 {
 288         struct des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 289         unsigned int bsize = DES3_EDE_BLOCK_SIZE;
 290         unsigned int nbytes = walk->nbytes;
 291         __be64 *src = (__be64 *)walk->src.virt.addr;
 292         __be64 *dst = (__be64 *)walk->dst.virt.addr;
 293         u64 ctrblk = be64_to_cpu(*(__be64 *)walk->iv);
 294         __be64 ctrblocks[3];
 295
 296         /* Process four block batch */
 297         if (nbytes >= bsize * 3) {
 298                 do {
 299                         /* create ctrblks for parallel encrypt */
 300                         ctrblocks[0] = cpu_to_be64(ctrblk++);
 301                         ctrblocks[1] = cpu_to_be64(ctrblk++);
 302                         ctrblocks[2] = cpu_to_be64(ctrblk++);
 303
 304                         des3_ede_enc_blk_3way(ctx, (u8 *)ctrblocks,
 305                                               (u8 *)ctrblocks);
 306
 307                         dst[0] = src[0] ^ ctrblocks[0];
 308                         dst[1] = src[1] ^ ctrblocks[1];
 309                         dst[2] = src[2] ^ ctrblocks[2];
 310
 311                         src += 3;
 312                         dst += 3;
 313                 } while ((nbytes -= bsize * 3) >= bsize * 3);
 314
 315                 if (nbytes < bsize)
 316                         goto done;
 317         }
 318
 319         /* Handle leftovers */
 320         do {
 321                 ctrblocks[0] = cpu_to_be64(ctrblk++);
 322
 323                 des3_ede_enc_blk(ctx, (u8 *)ctrblocks, (u8 *)ctrblocks);
 324
 325                 dst[0] = src[0] ^ ctrblocks[0];
 326
 327                 src += 1;
 328                 dst += 1;
 329         } while ((nbytes -= bsize) >= bsize);
 330
 331 done:
 332         *(__be64 *)walk->iv = cpu_to_be64(ctrblk);
 333         return nbytes;
 334 }
 335
 336 static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 337                      struct scatterlist *src, unsigned int nbytes)
 338 {
 339         struct blkcipher_walk walk;
 340         int err;
 341
 342         blkcipher_walk_init(&walk, dst, src, nbytes);
 343         err = blkcipher_walk_virt_block(desc, &walk, DES3_EDE_BLOCK_SIZE);
 344
 345         while ((nbytes = walk.nbytes) >= DES3_EDE_BLOCK_SIZE) {
 346                 nbytes = __ctr_crypt(desc, &walk);
 347                 err = blkcipher_walk_done(desc, &walk, nbytes);
 348         }
 349
 350         if (walk.nbytes) {
 351                 ctr_crypt_final(crypto_blkcipher_ctx(desc->tfm), &walk);
 352                 err = blkcipher_walk_done(desc, &walk, 0);
 353         }
 354
 355         return err;
 356 }
 357
 358 static int des3_ede_x86_setkey(struct crypto_tfm *tfm, const u8 *key,
 359                                unsigned int keylen)
 360 {
 361         struct des3_ede_x86_ctx *ctx = crypto_tfm_ctx(tfm);
 362         u32 i, j, tmp;
 363         int err;
 364
 365         /* Generate encryption context using generic implementation. */
 366         err = __des3_ede_setkey(ctx->enc_expkey, &tfm->crt_flags, key, keylen);
 367         if (err < 0)
 368                 return err;
 369
 370         /* Fix encryption context for this implementation and form decryption
 371          * context. */
 372         j = DES3_EDE_EXPKEY_WORDS - 2;
 373         for (i = 0; i < DES3_EDE_EXPKEY_WORDS; i += 2, j -= 2) {
 374                 tmp = ror32(ctx->enc_expkey[i + 1], 4);
 375                 ctx->enc_expkey[i + 1] = tmp;
 376
 377                 ctx->dec_expkey[j + 0] = ctx->enc_expkey[i + 0];
 378                 ctx->dec_expkey[j + 1] = tmp;
 379         }
 380
 381         return 0;
 382 }
 383
 384 static struct crypto_alg des3_ede_algs[4] = { {
 385         .cra_name               = "des3_ede",
 386         .cra_driver_name        = "des3_ede-asm",
 387         .cra_priority           = 200,
 388         .cra_flags              = CRYPTO_ALG_TYPE_CIPHER,
 389         .cra_blocksize          = DES3_EDE_BLOCK_SIZE,
 390         .cra_ctxsize            = sizeof(struct des3_ede_x86_ctx),
 391         .cra_alignmask          = 0,
 392         .cra_module             = THIS_MODULE,
 393         .cra_u = {
 394                 .cipher = {
 395                         .cia_min_keysize        = DES3_EDE_KEY_SIZE,
 396                         .cia_max_keysize        = DES3_EDE_KEY_SIZE,
 397                         .cia_setkey             = des3_ede_x86_setkey,
 398                         .cia_encrypt            = des3_ede_x86_encrypt,
 399                         .cia_decrypt            = des3_ede_x86_decrypt,
 400                 }
 401         }
 402 }, {
 403         .cra_name               = "ecb(des3_ede)",
 404         .cra_driver_name        = "ecb-des3_ede-asm",
 405         .cra_priority           = 300,
 406         .cra_flags              = CRYPTO_ALG_TYPE_BLKCIPHER,
 407         .cra_blocksize          = DES3_EDE_BLOCK_SIZE,
 408         .cra_ctxsize            = sizeof(struct des3_ede_x86_ctx),
 409         .cra_alignmask          = 0,
 410         .cra_type               = &crypto_blkcipher_type,
 411         .cra_module             = THIS_MODULE,
 412         .cra_u = {
 413                 .blkcipher = {
 414                         .min_keysize    = DES3_EDE_KEY_SIZE,
 415                         .max_keysize    = DES3_EDE_KEY_SIZE,
 416                         .setkey         = des3_ede_x86_setkey,
 417                         .encrypt        = ecb_encrypt,
 418                         .decrypt        = ecb_decrypt,
 419                 },
 420         },
 421 }, {
 422         .cra_name               = "cbc(des3_ede)",
 423         .cra_driver_name        = "cbc-des3_ede-asm",
 424         .cra_priority           = 300,
 425         .cra_flags              = CRYPTO_ALG_TYPE_BLKCIPHER,
 426         .cra_blocksize          = DES3_EDE_BLOCK_SIZE,
 427         .cra_ctxsize            = sizeof(struct des3_ede_x86_ctx),
 428         .cra_alignmask          = 0,
 429         .cra_type               = &crypto_blkcipher_type,
 430         .cra_module             = THIS_MODULE,
 431         .cra_u = {
 432                 .blkcipher = {
 433                         .min_keysize    = DES3_EDE_KEY_SIZE,
 434                         .max_keysize    = DES3_EDE_KEY_SIZE,
 435                         .ivsize         = DES3_EDE_BLOCK_SIZE,
 436                         .setkey         = des3_ede_x86_setkey,
 437                         .encrypt        = cbc_encrypt,
 438                         .decrypt        = cbc_decrypt,
 439                 },
 440         },
 441 }, {
 442         .cra_name               = "ctr(des3_ede)",
 443         .cra_driver_name        = "ctr-des3_ede-asm",
 444         .cra_priority           = 300,
 445         .cra_flags              = CRYPTO_ALG_TYPE_BLKCIPHER,
 446         .cra_blocksize          = 1,
 447         .cra_ctxsize            = sizeof(struct des3_ede_x86_ctx),
 448         .cra_alignmask          = 0,
 449         .cra_type               = &crypto_blkcipher_type,
 450         .cra_module             = THIS_MODULE,
 451         .cra_u = {
 452                 .blkcipher = {
 453                         .min_keysize    = DES3_EDE_KEY_SIZE,
 454                         .max_keysize    = DES3_EDE_KEY_SIZE,
 455                         .ivsize         = DES3_EDE_BLOCK_SIZE,
 456                         .setkey         = des3_ede_x86_setkey,
 457                         .encrypt        = ctr_crypt,
 458                         .decrypt        = ctr_crypt,
 459                 },
 460         },
 461 } };
 462
 463 static bool is_blacklisted_cpu(void)
 464 {
 465         if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
 466                 return false;
 467
 468         if (boot_cpu_data.x86 == 0x0f) {
 469                 /*
 470                  * On Pentium 4, des3_ede-x86_64 is slower than generic C
 471                  * implementation because use of 64bit rotates (which are really
 472                  * slow on P4). Therefore blacklist P4s.
 473                  */
 474                 return true;
 475         }
 476
 477         return false;
 478 }
 479
 480 static int force;
 481 module_param(force, int, 0);
 482 MODULE_PARM_DESC(force, "Force module load, ignore CPU blacklist");
 483
 484 static int __init des3_ede_x86_init(void)
 485 {
 486         if (!force && is_blacklisted_cpu()) {
 487                 pr_info("des3_ede-x86_64: performance on this CPU would be suboptimal: disabling des3_ede-x86_64.\n");
 488                 return -ENODEV;
 489         }
 490
 491         return crypto_register_algs(des3_ede_algs, ARRAY_SIZE(des3_ede_algs));
 492 }
 493
 494 static void __exit des3_ede_x86_fini(void)
 495 {
 496         crypto_unregister_algs(des3_ede_algs, ARRAY_SIZE(des3_ede_algs));
 497 }
 498
 499 module_init(des3_ede_x86_init);
 500 module_exit(des3_ede_x86_fini);
 501
 502 MODULE_LICENSE("GPL");
 503 MODULE_DESCRIPTION("Triple DES EDE Cipher Algorithm, asm optimized");
 504 MODULE_ALIAS_CRYPTO("des3_ede");
 505 MODULE_ALIAS_CRYPTO("des3_ede-asm");
 506 MODULE_AUTHOR("Jussi Kivilinna <jussi.kivilinna@iki.fi>");