arch/x86/crypto/des3_ede_glue.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Glue Code for assembler optimized version of 3DES
   4  *
   5  * Copyright © 2014 Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
   6  *
   7  * CBC & ECB parts based on code (crypto/cbc.c,ecb.c) by:
   8  *   Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
   9  * CTR part based on code (crypto/ctr.c) by:
  10  *   (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com>
  11  */
  12
  13 #include <crypto/algapi.h>
  14 #include <crypto/des.h>
  15 #include <crypto/internal/skcipher.h>
  16 #include <linux/crypto.h>
  17 #include <linux/init.h>
  18 #include <linux/module.h>
  19 #include <linux/types.h>
  20
  21 struct des3_ede_x86_ctx {
  22         u32 enc_expkey[DES3_EDE_EXPKEY_WORDS];
  23         u32 dec_expkey[DES3_EDE_EXPKEY_WORDS];
  24 };
  25
  26 /* regular block cipher functions */
  27 asmlinkage void des3_ede_x86_64_crypt_blk(const u32 *expkey, u8 *dst,
  28                                           const u8 *src);
  29
  30 /* 3-way parallel cipher functions */
  31 asmlinkage void des3_ede_x86_64_crypt_blk_3way(const u32 *expkey, u8 *dst,
  32                                                const u8 *src);
  33
  34 static inline void des3_ede_enc_blk(struct des3_ede_x86_ctx *ctx, u8 *dst,
  35                                     const u8 *src)
  36 {
  37         u32 *enc_ctx = ctx->enc_expkey;
  38
  39         des3_ede_x86_64_crypt_blk(enc_ctx, dst, src);
  40 }
  41
  42 static inline void des3_ede_dec_blk(struct des3_ede_x86_ctx *ctx, u8 *dst,
  43                                     const u8 *src)
  44 {
  45         u32 *dec_ctx = ctx->dec_expkey;
  46
  47         des3_ede_x86_64_crypt_blk(dec_ctx, dst, src);
  48 }
  49
  50 static inline void des3_ede_enc_blk_3way(struct des3_ede_x86_ctx *ctx, u8 *dst,
  51                                          const u8 *src)
  52 {
  53         u32 *enc_ctx = ctx->enc_expkey;
  54
  55         des3_ede_x86_64_crypt_blk_3way(enc_ctx, dst, src);
  56 }
  57
  58 static inline void des3_ede_dec_blk_3way(struct des3_ede_x86_ctx *ctx, u8 *dst,
  59                                          const u8 *src)
  60 {
  61         u32 *dec_ctx = ctx->dec_expkey;
  62
  63         des3_ede_x86_64_crypt_blk_3way(dec_ctx, dst, src);
  64 }
  65
  66 static void des3_ede_x86_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
  67 {
  68         des3_ede_enc_blk(crypto_tfm_ctx(tfm), dst, src);
  69 }
  70
  71 static void des3_ede_x86_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
  72 {
  73         des3_ede_dec_blk(crypto_tfm_ctx(tfm), dst, src);
  74 }
  75
  76 static int ecb_crypt(struct skcipher_request *req, const u32 *expkey)
  77 {
  78         const unsigned int bsize = DES3_EDE_BLOCK_SIZE;
  79         struct skcipher_walk walk;
  80         unsigned int nbytes;
  81         int err;
  82
  83         err = skcipher_walk_virt(&walk, req, false);
  84
  85         while ((nbytes = walk.nbytes)) {
  86                 u8 *wsrc = walk.src.virt.addr;
  87                 u8 *wdst = walk.dst.virt.addr;
  88
  89                 /* Process four block batch */
  90                 if (nbytes >= bsize * 3) {
  91                         do {
  92                                 des3_ede_x86_64_crypt_blk_3way(expkey, wdst,
  93                                                                wsrc);
  94
  95                                 wsrc += bsize * 3;
  96                                 wdst += bsize * 3;
  97                                 nbytes -= bsize * 3;
  98                         } while (nbytes >= bsize * 3);
  99
 100                         if (nbytes < bsize)
 101                                 goto done;
 102                 }
 103
 104                 /* Handle leftovers */
 105                 do {
 106                         des3_ede_x86_64_crypt_blk(expkey, wdst, wsrc);
 107
 108                         wsrc += bsize;
 109                         wdst += bsize;
 110                         nbytes -= bsize;
 111                 } while (nbytes >= bsize);
 112
 113 done:
 114                 err = skcipher_walk_done(&walk, nbytes);
 115         }
 116
 117         return err;
 118 }
 119
 120 static int ecb_encrypt(struct skcipher_request *req)
 121 {
 122         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 123         struct des3_ede_x86_ctx *ctx = crypto_skcipher_ctx(tfm);
 124
 125         return ecb_crypt(req, ctx->enc_expkey);
 126 }
 127
 128 static int ecb_decrypt(struct skcipher_request *req)
 129 {
 130         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 131         struct des3_ede_x86_ctx *ctx = crypto_skcipher_ctx(tfm);
 132
 133         return ecb_crypt(req, ctx->dec_expkey);
 134 }
 135
 136 static unsigned int __cbc_encrypt(struct des3_ede_x86_ctx *ctx,
 137                                   struct skcipher_walk *walk)
 138 {
 139         unsigned int bsize = DES3_EDE_BLOCK_SIZE;
 140         unsigned int nbytes = walk->nbytes;
 141         u64 *src = (u64 *)walk->src.virt.addr;
 142         u64 *dst = (u64 *)walk->dst.virt.addr;
 143         u64 *iv = (u64 *)walk->iv;
 144
 145         do {
 146                 *dst = *src ^ *iv;
 147                 des3_ede_enc_blk(ctx, (u8 *)dst, (u8 *)dst);
 148                 iv = dst;
 149
 150                 src += 1;
 151                 dst += 1;
 152                 nbytes -= bsize;
 153         } while (nbytes >= bsize);
 154
 155         *(u64 *)walk->iv = *iv;
 156         return nbytes;
 157 }
 158
 159 static int cbc_encrypt(struct skcipher_request *req)
 160 {
 161         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 162         struct des3_ede_x86_ctx *ctx = crypto_skcipher_ctx(tfm);
 163         struct skcipher_walk walk;
 164         unsigned int nbytes;
 165         int err;
 166
 167         err = skcipher_walk_virt(&walk, req, false);
 168
 169         while ((nbytes = walk.nbytes)) {
 170                 nbytes = __cbc_encrypt(ctx, &walk);
 171                 err = skcipher_walk_done(&walk, nbytes);
 172         }
 173
 174         return err;
 175 }
 176
 177 static unsigned int __cbc_decrypt(struct des3_ede_x86_ctx *ctx,
 178                                   struct skcipher_walk *walk)
 179 {
 180         unsigned int bsize = DES3_EDE_BLOCK_SIZE;
 181         unsigned int nbytes = walk->nbytes;
 182         u64 *src = (u64 *)walk->src.virt.addr;
 183         u64 *dst = (u64 *)walk->dst.virt.addr;
 184         u64 ivs[3 - 1];
 185         u64 last_iv;
 186
 187         /* Start of the last block. */
 188         src += nbytes / bsize - 1;
 189         dst += nbytes / bsize - 1;
 190
 191         last_iv = *src;
 192
 193         /* Process four block batch */
 194         if (nbytes >= bsize * 3) {
 195                 do {
 196                         nbytes -= bsize * 3 - bsize;
 197                         src -= 3 - 1;
 198                         dst -= 3 - 1;
 199
 200                         ivs[0] = src[0];
 201                         ivs[1] = src[1];
 202
 203                         des3_ede_dec_blk_3way(ctx, (u8 *)dst, (u8 *)src);
 204
 205                         dst[1] ^= ivs[0];
 206                         dst[2] ^= ivs[1];
 207
 208                         nbytes -= bsize;
 209                         if (nbytes < bsize)
 210                                 goto done;
 211
 212                         *dst ^= *(src - 1);
 213                         src -= 1;
 214                         dst -= 1;
 215                 } while (nbytes >= bsize * 3);
 216         }
 217
 218         /* Handle leftovers */
 219         for (;;) {
 220                 des3_ede_dec_blk(ctx, (u8 *)dst, (u8 *)src);
 221
 222                 nbytes -= bsize;
 223                 if (nbytes < bsize)
 224                         break;
 225
 226                 *dst ^= *(src - 1);
 227                 src -= 1;
 228                 dst -= 1;
 229         }
 230
 231 done:
 232         *dst ^= *(u64 *)walk->iv;
 233         *(u64 *)walk->iv = last_iv;
 234
 235         return nbytes;
 236 }
 237
 238 static int cbc_decrypt(struct skcipher_request *req)
 239 {
 240         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 241         struct des3_ede_x86_ctx *ctx = crypto_skcipher_ctx(tfm);
 242         struct skcipher_walk walk;
 243         unsigned int nbytes;
 244         int err;
 245
 246         err = skcipher_walk_virt(&walk, req, false);
 247
 248         while ((nbytes = walk.nbytes)) {
 249                 nbytes = __cbc_decrypt(ctx, &walk);
 250                 err = skcipher_walk_done(&walk, nbytes);
 251         }
 252
 253         return err;
 254 }
 255
 256 static void ctr_crypt_final(struct des3_ede_x86_ctx *ctx,
 257                             struct skcipher_walk *walk)
 258 {
 259         u8 *ctrblk = walk->iv;
 260         u8 keystream[DES3_EDE_BLOCK_SIZE];
 261         u8 *src = walk->src.virt.addr;
 262         u8 *dst = walk->dst.virt.addr;
 263         unsigned int nbytes = walk->nbytes;
 264
 265         des3_ede_enc_blk(ctx, keystream, ctrblk);
 266         crypto_xor_cpy(dst, keystream, src, nbytes);
 267
 268         crypto_inc(ctrblk, DES3_EDE_BLOCK_SIZE);
 269 }
 270
 271 static unsigned int __ctr_crypt(struct des3_ede_x86_ctx *ctx,
 272                                 struct skcipher_walk *walk)
 273 {
 274         unsigned int bsize = DES3_EDE_BLOCK_SIZE;
 275         unsigned int nbytes = walk->nbytes;
 276         __be64 *src = (__be64 *)walk->src.virt.addr;
 277         __be64 *dst = (__be64 *)walk->dst.virt.addr;
 278         u64 ctrblk = be64_to_cpu(*(__be64 *)walk->iv);
 279         __be64 ctrblocks[3];
 280
 281         /* Process four block batch */
 282         if (nbytes >= bsize * 3) {
 283                 do {
 284                         /* create ctrblks for parallel encrypt */
 285                         ctrblocks[0] = cpu_to_be64(ctrblk++);
 286                         ctrblocks[1] = cpu_to_be64(ctrblk++);
 287                         ctrblocks[2] = cpu_to_be64(ctrblk++);
 288
 289                         des3_ede_enc_blk_3way(ctx, (u8 *)ctrblocks,
 290                                               (u8 *)ctrblocks);
 291
 292                         dst[0] = src[0] ^ ctrblocks[0];
 293                         dst[1] = src[1] ^ ctrblocks[1];
 294                         dst[2] = src[2] ^ ctrblocks[2];
 295
 296                         src += 3;
 297                         dst += 3;
 298                 } while ((nbytes -= bsize * 3) >= bsize * 3);
 299
 300                 if (nbytes < bsize)
 301                         goto done;
 302         }
 303
 304         /* Handle leftovers */
 305         do {
 306                 ctrblocks[0] = cpu_to_be64(ctrblk++);
 307
 308                 des3_ede_enc_blk(ctx, (u8 *)ctrblocks, (u8 *)ctrblocks);
 309
 310                 dst[0] = src[0] ^ ctrblocks[0];
 311
 312                 src += 1;
 313                 dst += 1;
 314         } while ((nbytes -= bsize) >= bsize);
 315
 316 done:
 317         *(__be64 *)walk->iv = cpu_to_be64(ctrblk);
 318         return nbytes;
 319 }
 320
 321 static int ctr_crypt(struct skcipher_request *req)
 322 {
 323         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 324         struct des3_ede_x86_ctx *ctx = crypto_skcipher_ctx(tfm);
 325         struct skcipher_walk walk;
 326         unsigned int nbytes;
 327         int err;
 328
 329         err = skcipher_walk_virt(&walk, req, false);
 330
 331         while ((nbytes = walk.nbytes) >= DES3_EDE_BLOCK_SIZE) {
 332                 nbytes = __ctr_crypt(ctx, &walk);
 333                 err = skcipher_walk_done(&walk, nbytes);
 334         }
 335
 336         if (nbytes) {
 337                 ctr_crypt_final(ctx, &walk);
 338                 err = skcipher_walk_done(&walk, 0);
 339         }
 340
 341         return err;
 342 }
 343
 344 static int des3_ede_x86_setkey(struct crypto_tfm *tfm, const u8 *key,
 345                                unsigned int keylen)
 346 {
 347         struct des3_ede_x86_ctx *ctx = crypto_tfm_ctx(tfm);
 348         u32 i, j, tmp;
 349         int err;
 350
 351         /* Generate encryption context using generic implementation. */
 352         err = __des3_ede_setkey(ctx->enc_expkey, &tfm->crt_flags, key, keylen);
 353         if (err < 0)
 354                 return err;
 355
 356         /* Fix encryption context for this implementation and form decryption
 357          * context. */
 358         j = DES3_EDE_EXPKEY_WORDS - 2;
 359         for (i = 0; i < DES3_EDE_EXPKEY_WORDS; i += 2, j -= 2) {
 360                 tmp = ror32(ctx->enc_expkey[i + 1], 4);
 361                 ctx->enc_expkey[i + 1] = tmp;
 362
 363                 ctx->dec_expkey[j + 0] = ctx->enc_expkey[i + 0];
 364                 ctx->dec_expkey[j + 1] = tmp;
 365         }
 366
 367         return 0;
 368 }
 369
 370 static int des3_ede_x86_setkey_skcipher(struct crypto_skcipher *tfm,
 371                                         const u8 *key,
 372                                         unsigned int keylen)
 373 {
 374         return des3_ede_x86_setkey(&tfm->base, key, keylen);
 375 }
 376
 377 static struct crypto_alg des3_ede_cipher = {
 378         .cra_name               = "des3_ede",
 379         .cra_driver_name        = "des3_ede-asm",
 380         .cra_priority           = 200,
 381         .cra_flags              = CRYPTO_ALG_TYPE_CIPHER,
 382         .cra_blocksize          = DES3_EDE_BLOCK_SIZE,
 383         .cra_ctxsize            = sizeof(struct des3_ede_x86_ctx),
 384         .cra_alignmask          = 0,
 385         .cra_module             = THIS_MODULE,
 386         .cra_u = {
 387                 .cipher = {
 388                         .cia_min_keysize        = DES3_EDE_KEY_SIZE,
 389                         .cia_max_keysize        = DES3_EDE_KEY_SIZE,
 390                         .cia_setkey             = des3_ede_x86_setkey,
 391                         .cia_encrypt            = des3_ede_x86_encrypt,
 392                         .cia_decrypt            = des3_ede_x86_decrypt,
 393                 }
 394         }
 395 };
 396
 397 static struct skcipher_alg des3_ede_skciphers[] = {
 398         {
 399                 .base.cra_name          = "ecb(des3_ede)",
 400                 .base.cra_driver_name   = "ecb-des3_ede-asm",
 401                 .base.cra_priority      = 300,
 402                 .base.cra_blocksize     = DES3_EDE_BLOCK_SIZE,
 403                 .base.cra_ctxsize       = sizeof(struct des3_ede_x86_ctx),
 404                 .base.cra_module        = THIS_MODULE,
 405                 .min_keysize            = DES3_EDE_KEY_SIZE,
 406                 .max_keysize            = DES3_EDE_KEY_SIZE,
 407                 .setkey                 = des3_ede_x86_setkey_skcipher,
 408                 .encrypt                = ecb_encrypt,
 409                 .decrypt                = ecb_decrypt,
 410         }, {
 411                 .base.cra_name          = "cbc(des3_ede)",
 412                 .base.cra_driver_name   = "cbc-des3_ede-asm",
 413                 .base.cra_priority      = 300,
 414                 .base.cra_blocksize     = DES3_EDE_BLOCK_SIZE,
 415                 .base.cra_ctxsize       = sizeof(struct des3_ede_x86_ctx),
 416                 .base.cra_module        = THIS_MODULE,
 417                 .min_keysize            = DES3_EDE_KEY_SIZE,
 418                 .max_keysize            = DES3_EDE_KEY_SIZE,
 419                 .ivsize                 = DES3_EDE_BLOCK_SIZE,
 420                 .setkey                 = des3_ede_x86_setkey_skcipher,
 421                 .encrypt                = cbc_encrypt,
 422                 .decrypt                = cbc_decrypt,
 423         }, {
 424                 .base.cra_name          = "ctr(des3_ede)",
 425                 .base.cra_driver_name   = "ctr-des3_ede-asm",
 426                 .base.cra_priority      = 300,
 427                 .base.cra_blocksize     = 1,
 428                 .base.cra_ctxsize       = sizeof(struct des3_ede_x86_ctx),
 429                 .base.cra_module        = THIS_MODULE,
 430                 .min_keysize            = DES3_EDE_KEY_SIZE,
 431                 .max_keysize            = DES3_EDE_KEY_SIZE,
 432                 .ivsize                 = DES3_EDE_BLOCK_SIZE,
 433                 .chunksize              = DES3_EDE_BLOCK_SIZE,
 434                 .setkey                 = des3_ede_x86_setkey_skcipher,
 435                 .encrypt                = ctr_crypt,
 436                 .decrypt                = ctr_crypt,
 437         }
 438 };
 439
 440 static bool is_blacklisted_cpu(void)
 441 {
 442         if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
 443                 return false;
 444
 445         if (boot_cpu_data.x86 == 0x0f) {
 446                 /*
 447                  * On Pentium 4, des3_ede-x86_64 is slower than generic C
 448                  * implementation because use of 64bit rotates (which are really
 449                  * slow on P4). Therefore blacklist P4s.
 450                  */
 451                 return true;
 452         }
 453
 454         return false;
 455 }
 456
 457 static int force;
 458 module_param(force, int, 0);
 459 MODULE_PARM_DESC(force, "Force module load, ignore CPU blacklist");
 460
 461 static int __init des3_ede_x86_init(void)
 462 {
 463         int err;
 464
 465         if (!force && is_blacklisted_cpu()) {
 466                 pr_info("des3_ede-x86_64: performance on this CPU would be suboptimal: disabling des3_ede-x86_64.\n");
 467                 return -ENODEV;
 468         }
 469
 470         err = crypto_register_alg(&des3_ede_cipher);
 471         if (err)
 472                 return err;
 473
 474         err = crypto_register_skciphers(des3_ede_skciphers,
 475                                         ARRAY_SIZE(des3_ede_skciphers));
 476         if (err)
 477                 crypto_unregister_alg(&des3_ede_cipher);
 478
 479         return err;
 480 }
 481
 482 static void __exit des3_ede_x86_fini(void)
 483 {
 484         crypto_unregister_alg(&des3_ede_cipher);
 485         crypto_unregister_skciphers(des3_ede_skciphers,
 486                                     ARRAY_SIZE(des3_ede_skciphers));
 487 }
 488
 489 module_init(des3_ede_x86_init);
 490 module_exit(des3_ede_x86_fini);
 491
 492 MODULE_LICENSE("GPL");
 493 MODULE_DESCRIPTION("Triple DES EDE Cipher Algorithm, asm optimized");
 494 MODULE_ALIAS_CRYPTO("des3_ede");
 495 MODULE_ALIAS_CRYPTO("des3_ede-asm");
 496 MODULE_AUTHOR("Jussi Kivilinna <jussi.kivilinna@iki.fi>");