arch/x86/crypto/blowfish_glue.c

   1 /*
   2  * Glue Code for assembler optimized version of Blowfish
   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 <asm/processor.h>
  29 #include <crypto/blowfish.h>
  30 #include <linux/crypto.h>
  31 #include <linux/init.h>
  32 #include <linux/module.h>
  33 #include <linux/types.h>
  34 #include <crypto/algapi.h>
  35
  36 /* regular block cipher functions */
  37 asmlinkage void __blowfish_enc_blk(struct bf_ctx *ctx, u8 *dst, const u8 *src,
  38                                    bool xor);
  39 asmlinkage void blowfish_dec_blk(struct bf_ctx *ctx, u8 *dst, const u8 *src);
  40
  41 /* 4-way parallel cipher functions */
  42 asmlinkage void __blowfish_enc_blk_4way(struct bf_ctx *ctx, u8 *dst,
  43                                         const u8 *src, bool xor);
  44 asmlinkage void blowfish_dec_blk_4way(struct bf_ctx *ctx, u8 *dst,
  45                                       const u8 *src);
  46
  47 static inline void blowfish_enc_blk(struct bf_ctx *ctx, u8 *dst, const u8 *src)
  48 {
  49         __blowfish_enc_blk(ctx, dst, src, false);
  50 }
  51
  52 static inline void blowfish_enc_blk_xor(struct bf_ctx *ctx, u8 *dst,
  53                                         const u8 *src)
  54 {
  55         __blowfish_enc_blk(ctx, dst, src, true);
  56 }
  57
  58 static inline void blowfish_enc_blk_4way(struct bf_ctx *ctx, u8 *dst,
  59                                          const u8 *src)
  60 {
  61         __blowfish_enc_blk_4way(ctx, dst, src, false);
  62 }
  63
  64 static inline void blowfish_enc_blk_xor_4way(struct bf_ctx *ctx, u8 *dst,
  65                                       const u8 *src)
  66 {
  67         __blowfish_enc_blk_4way(ctx, dst, src, true);
  68 }
  69
  70 static void blowfish_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
  71 {
  72         blowfish_enc_blk(crypto_tfm_ctx(tfm), dst, src);
  73 }
  74
  75 static void blowfish_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
  76 {
  77         blowfish_dec_blk(crypto_tfm_ctx(tfm), dst, src);
  78 }
  79
  80 static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk,
  81                      void (*fn)(struct bf_ctx *, u8 *, const u8 *),
  82                      void (*fn_4way)(struct bf_ctx *, u8 *, const u8 *))
  83 {
  84         struct bf_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
  85         unsigned int bsize = BF_BLOCK_SIZE;
  86         unsigned int nbytes;
  87         int err;
  88
  89         err = blkcipher_walk_virt(desc, walk);
  90
  91         while ((nbytes = walk->nbytes)) {
  92                 u8 *wsrc = walk->src.virt.addr;
  93                 u8 *wdst = walk->dst.virt.addr;
  94
  95                 /* Process four block batch */
  96                 if (nbytes >= bsize * 4) {
  97                         do {
  98                                 fn_4way(ctx, wdst, wsrc);
  99
 100                                 wsrc += bsize * 4;
 101                                 wdst += bsize * 4;
 102                                 nbytes -= bsize * 4;
 103                         } while (nbytes >= bsize * 4);
 104
 105                         if (nbytes < bsize)
 106                                 goto done;
 107                 }
 108
 109                 /* Handle leftovers */
 110                 do {
 111                         fn(ctx, wdst, wsrc);
 112
 113                         wsrc += bsize;
 114                         wdst += bsize;
 115                         nbytes -= bsize;
 116                 } while (nbytes >= bsize);
 117
 118 done:
 119                 err = blkcipher_walk_done(desc, walk, nbytes);
 120         }
 121
 122         return err;
 123 }
 124
 125 static int ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 126                        struct scatterlist *src, unsigned int nbytes)
 127 {
 128         struct blkcipher_walk walk;
 129
 130         blkcipher_walk_init(&walk, dst, src, nbytes);
 131         return ecb_crypt(desc, &walk, blowfish_enc_blk, blowfish_enc_blk_4way);
 132 }
 133
 134 static int ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 135                        struct scatterlist *src, unsigned int nbytes)
 136 {
 137         struct blkcipher_walk walk;
 138
 139         blkcipher_walk_init(&walk, dst, src, nbytes);
 140         return ecb_crypt(desc, &walk, blowfish_dec_blk, blowfish_dec_blk_4way);
 141 }
 142
 143 static unsigned int __cbc_encrypt(struct blkcipher_desc *desc,
 144                                   struct blkcipher_walk *walk)
 145 {
 146         struct bf_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 147         unsigned int bsize = BF_BLOCK_SIZE;
 148         unsigned int nbytes = walk->nbytes;
 149         u64 *src = (u64 *)walk->src.virt.addr;
 150         u64 *dst = (u64 *)walk->dst.virt.addr;
 151         u64 *iv = (u64 *)walk->iv;
 152
 153         do {
 154                 *dst = *src ^ *iv;
 155                 blowfish_enc_blk(ctx, (u8 *)dst, (u8 *)dst);
 156                 iv = dst;
 157
 158                 src += 1;
 159                 dst += 1;
 160                 nbytes -= bsize;
 161         } while (nbytes >= bsize);
 162
 163         *(u64 *)walk->iv = *iv;
 164         return nbytes;
 165 }
 166
 167 static int cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 168                        struct scatterlist *src, unsigned int nbytes)
 169 {
 170         struct blkcipher_walk walk;
 171         int err;
 172
 173         blkcipher_walk_init(&walk, dst, src, nbytes);
 174         err = blkcipher_walk_virt(desc, &walk);
 175
 176         while ((nbytes = walk.nbytes)) {
 177                 nbytes = __cbc_encrypt(desc, &walk);
 178                 err = blkcipher_walk_done(desc, &walk, nbytes);
 179         }
 180
 181         return err;
 182 }
 183
 184 static unsigned int __cbc_decrypt(struct blkcipher_desc *desc,
 185                                   struct blkcipher_walk *walk)
 186 {
 187         struct bf_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 188         unsigned int bsize = BF_BLOCK_SIZE;
 189         unsigned int nbytes = walk->nbytes;
 190         u64 *src = (u64 *)walk->src.virt.addr;
 191         u64 *dst = (u64 *)walk->dst.virt.addr;
 192         u64 ivs[4 - 1];
 193         u64 last_iv;
 194
 195         /* Start of the last block. */
 196         src += nbytes / bsize - 1;
 197         dst += nbytes / bsize - 1;
 198
 199         last_iv = *src;
 200
 201         /* Process four block batch */
 202         if (nbytes >= bsize * 4) {
 203                 do {
 204                         nbytes -= bsize * 4 - bsize;
 205                         src -= 4 - 1;
 206                         dst -= 4 - 1;
 207
 208                         ivs[0] = src[0];
 209                         ivs[1] = src[1];
 210                         ivs[2] = src[2];
 211
 212                         blowfish_dec_blk_4way(ctx, (u8 *)dst, (u8 *)src);
 213
 214                         dst[1] ^= ivs[0];
 215                         dst[2] ^= ivs[1];
 216                         dst[3] ^= ivs[2];
 217
 218                         nbytes -= bsize;
 219                         if (nbytes < bsize)
 220                                 goto done;
 221
 222                         *dst ^= *(src - 1);
 223                         src -= 1;
 224                         dst -= 1;
 225                 } while (nbytes >= bsize * 4);
 226
 227                 if (nbytes < bsize)
 228                         goto done;
 229         }
 230
 231         /* Handle leftovers */
 232         for (;;) {
 233                 blowfish_dec_blk(ctx, (u8 *)dst, (u8 *)src);
 234
 235                 nbytes -= bsize;
 236                 if (nbytes < bsize)
 237                         break;
 238
 239                 *dst ^= *(src - 1);
 240                 src -= 1;
 241                 dst -= 1;
 242         }
 243
 244 done:
 245         *dst ^= *(u64 *)walk->iv;
 246         *(u64 *)walk->iv = last_iv;
 247
 248         return nbytes;
 249 }
 250
 251 static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 252                        struct scatterlist *src, unsigned int nbytes)
 253 {
 254         struct blkcipher_walk walk;
 255         int err;
 256
 257         blkcipher_walk_init(&walk, dst, src, nbytes);
 258         err = blkcipher_walk_virt(desc, &walk);
 259
 260         while ((nbytes = walk.nbytes)) {
 261                 nbytes = __cbc_decrypt(desc, &walk);
 262                 err = blkcipher_walk_done(desc, &walk, nbytes);
 263         }
 264
 265         return err;
 266 }
 267
 268 static void ctr_crypt_final(struct bf_ctx *ctx, struct blkcipher_walk *walk)
 269 {
 270         u8 *ctrblk = walk->iv;
 271         u8 keystream[BF_BLOCK_SIZE];
 272         u8 *src = walk->src.virt.addr;
 273         u8 *dst = walk->dst.virt.addr;
 274         unsigned int nbytes = walk->nbytes;
 275
 276         blowfish_enc_blk(ctx, keystream, ctrblk);
 277         crypto_xor(keystream, src, nbytes);
 278         memcpy(dst, keystream, nbytes);
 279
 280         crypto_inc(ctrblk, BF_BLOCK_SIZE);
 281 }
 282
 283 static unsigned int __ctr_crypt(struct blkcipher_desc *desc,
 284                                 struct blkcipher_walk *walk)
 285 {
 286         struct bf_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 287         unsigned int bsize = BF_BLOCK_SIZE;
 288         unsigned int nbytes = walk->nbytes;
 289         u64 *src = (u64 *)walk->src.virt.addr;
 290         u64 *dst = (u64 *)walk->dst.virt.addr;
 291         u64 ctrblk = be64_to_cpu(*(__be64 *)walk->iv);
 292         __be64 ctrblocks[4];
 293
 294         /* Process four block batch */
 295         if (nbytes >= bsize * 4) {
 296                 do {
 297                         if (dst != src) {
 298                                 dst[0] = src[0];
 299                                 dst[1] = src[1];
 300                                 dst[2] = src[2];
 301                                 dst[3] = src[3];
 302                         }
 303
 304                         /* create ctrblks for parallel encrypt */
 305                         ctrblocks[0] = cpu_to_be64(ctrblk++);
 306                         ctrblocks[1] = cpu_to_be64(ctrblk++);
 307                         ctrblocks[2] = cpu_to_be64(ctrblk++);
 308                         ctrblocks[3] = cpu_to_be64(ctrblk++);
 309
 310                         blowfish_enc_blk_xor_4way(ctx, (u8 *)dst,
 311                                                   (u8 *)ctrblocks);
 312
 313                         src += 4;
 314                         dst += 4;
 315                 } while ((nbytes -= bsize * 4) >= bsize * 4);
 316
 317                 if (nbytes < bsize)
 318                         goto done;
 319         }
 320
 321         /* Handle leftovers */
 322         do {
 323                 if (dst != src)
 324                         *dst = *src;
 325
 326                 ctrblocks[0] = cpu_to_be64(ctrblk++);
 327
 328                 blowfish_enc_blk_xor(ctx, (u8 *)dst, (u8 *)ctrblocks);
 329
 330                 src += 1;
 331                 dst += 1;
 332         } while ((nbytes -= bsize) >= bsize);
 333
 334 done:
 335         *(__be64 *)walk->iv = cpu_to_be64(ctrblk);
 336         return nbytes;
 337 }
 338
 339 static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 340                      struct scatterlist *src, unsigned int nbytes)
 341 {
 342         struct blkcipher_walk walk;
 343         int err;
 344
 345         blkcipher_walk_init(&walk, dst, src, nbytes);
 346         err = blkcipher_walk_virt_block(desc, &walk, BF_BLOCK_SIZE);
 347
 348         while ((nbytes = walk.nbytes) >= BF_BLOCK_SIZE) {
 349                 nbytes = __ctr_crypt(desc, &walk);
 350                 err = blkcipher_walk_done(desc, &walk, nbytes);
 351         }
 352
 353         if (walk.nbytes) {
 354                 ctr_crypt_final(crypto_blkcipher_ctx(desc->tfm), &walk);
 355                 err = blkcipher_walk_done(desc, &walk, 0);
 356         }
 357
 358         return err;
 359 }
 360
 361 static struct crypto_alg bf_algs[4] = { {
 362         .cra_name               = "blowfish",
 363         .cra_driver_name        = "blowfish-asm",
 364         .cra_priority           = 200,
 365         .cra_flags              = CRYPTO_ALG_TYPE_CIPHER,
 366         .cra_blocksize          = BF_BLOCK_SIZE,
 367         .cra_ctxsize            = sizeof(struct bf_ctx),
 368         .cra_alignmask          = 0,
 369         .cra_module             = THIS_MODULE,
 370         .cra_u = {
 371                 .cipher = {
 372                         .cia_min_keysize        = BF_MIN_KEY_SIZE,
 373                         .cia_max_keysize        = BF_MAX_KEY_SIZE,
 374                         .cia_setkey             = blowfish_setkey,
 375                         .cia_encrypt            = blowfish_encrypt,
 376                         .cia_decrypt            = blowfish_decrypt,
 377                 }
 378         }
 379 }, {
 380         .cra_name               = "ecb(blowfish)",
 381         .cra_driver_name        = "ecb-blowfish-asm",
 382         .cra_priority           = 300,
 383         .cra_flags              = CRYPTO_ALG_TYPE_BLKCIPHER,
 384         .cra_blocksize          = BF_BLOCK_SIZE,
 385         .cra_ctxsize            = sizeof(struct bf_ctx),
 386         .cra_alignmask          = 0,
 387         .cra_type               = &crypto_blkcipher_type,
 388         .cra_module             = THIS_MODULE,
 389         .cra_u = {
 390                 .blkcipher = {
 391                         .min_keysize    = BF_MIN_KEY_SIZE,
 392                         .max_keysize    = BF_MAX_KEY_SIZE,
 393                         .setkey         = blowfish_setkey,
 394                         .encrypt        = ecb_encrypt,
 395                         .decrypt        = ecb_decrypt,
 396                 },
 397         },
 398 }, {
 399         .cra_name               = "cbc(blowfish)",
 400         .cra_driver_name        = "cbc-blowfish-asm",
 401         .cra_priority           = 300,
 402         .cra_flags              = CRYPTO_ALG_TYPE_BLKCIPHER,
 403         .cra_blocksize          = BF_BLOCK_SIZE,
 404         .cra_ctxsize            = sizeof(struct bf_ctx),
 405         .cra_alignmask          = 0,
 406         .cra_type               = &crypto_blkcipher_type,
 407         .cra_module             = THIS_MODULE,
 408         .cra_u = {
 409                 .blkcipher = {
 410                         .min_keysize    = BF_MIN_KEY_SIZE,
 411                         .max_keysize    = BF_MAX_KEY_SIZE,
 412                         .ivsize         = BF_BLOCK_SIZE,
 413                         .setkey         = blowfish_setkey,
 414                         .encrypt        = cbc_encrypt,
 415                         .decrypt        = cbc_decrypt,
 416                 },
 417         },
 418 }, {
 419         .cra_name               = "ctr(blowfish)",
 420         .cra_driver_name        = "ctr-blowfish-asm",
 421         .cra_priority           = 300,
 422         .cra_flags              = CRYPTO_ALG_TYPE_BLKCIPHER,
 423         .cra_blocksize          = 1,
 424         .cra_ctxsize            = sizeof(struct bf_ctx),
 425         .cra_alignmask          = 0,
 426         .cra_type               = &crypto_blkcipher_type,
 427         .cra_module             = THIS_MODULE,
 428         .cra_u = {
 429                 .blkcipher = {
 430                         .min_keysize    = BF_MIN_KEY_SIZE,
 431                         .max_keysize    = BF_MAX_KEY_SIZE,
 432                         .ivsize         = BF_BLOCK_SIZE,
 433                         .setkey         = blowfish_setkey,
 434                         .encrypt        = ctr_crypt,
 435                         .decrypt        = ctr_crypt,
 436                 },
 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, blowfish-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 init(void)
 462 {
 463         if (!force && is_blacklisted_cpu()) {
 464                 printk(KERN_INFO
 465                         "blowfish-x86_64: performance on this CPU "
 466                         "would be suboptimal: disabling "
 467                         "blowfish-x86_64.\n");
 468                 return -ENODEV;
 469         }
 470
 471         return crypto_register_algs(bf_algs, ARRAY_SIZE(bf_algs));
 472 }
 473
 474 static void __exit fini(void)
 475 {
 476         crypto_unregister_algs(bf_algs, ARRAY_SIZE(bf_algs));
 477 }
 478
 479 module_init(init);
 480 module_exit(fini);
 481
 482 MODULE_LICENSE("GPL");
 483 MODULE_DESCRIPTION("Blowfish Cipher Algorithm, asm optimized");
 484 MODULE_ALIAS("blowfish");
 485 MODULE_ALIAS("blowfish-asm");