crypto/simd.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Shared crypto simd helpers
   4  *
   5  * Copyright (c) 2012 Jussi Kivilinna <[email protected]>
   6  * Copyright (c) 2016 Herbert Xu <[email protected]>
   7  * Copyright (c) 2019 Google LLC
   8  *
   9  * Based on aesni-intel_glue.c by:
  10  *  Copyright (C) 2008, Intel Corp.
  11  *    Author: Huang Ying <[email protected]>
  12  */
  13
  14 /*
  15  * Shared crypto SIMD helpers.  These functions dynamically create and register
  16  * an skcipher or AEAD algorithm that wraps another, internal algorithm.  The
  17  * wrapper ensures that the internal algorithm is only executed in a context
  18  * where SIMD instructions are usable, i.e. where may_use_simd() returns true.
  19  * If SIMD is already usable, the wrapper directly calls the internal algorithm.
  20  * Otherwise it defers execution to a workqueue via cryptd.
  21  *
  22  * This is an alternative to the internal algorithm implementing a fallback for
  23  * the !may_use_simd() case itself.
  24  *
  25  * Note that the wrapper algorithm is asynchronous, i.e. it has the
  26  * CRYPTO_ALG_ASYNC flag set.  Therefore it won't be found by users who
  27  * explicitly allocate a synchronous algorithm.
  28  */
  29
  30 #include <crypto/cryptd.h>
  31 #include <crypto/internal/aead.h>
  32 #include <crypto/internal/simd.h>
  33 #include <crypto/internal/skcipher.h>
  34 #include <linux/kernel.h>
  35 #include <linux/module.h>
  36 #include <linux/preempt.h>
  37 #include <asm/simd.h>
  38
  39 /* skcipher support */
  40
  41 struct simd_skcipher_alg {
  42         const char *ialg_name;
  43         struct skcipher_alg alg;
  44 };
  45
  46 struct simd_skcipher_ctx {
  47         struct cryptd_skcipher *cryptd_tfm;
  48 };
  49
  50 static int simd_skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
  51                                 unsigned int key_len)
  52 {
  53         struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
  54         struct crypto_skcipher *child = &ctx->cryptd_tfm->base;
  55
  56         crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
  57         crypto_skcipher_set_flags(child, crypto_skcipher_get_flags(tfm) &
  58                                          CRYPTO_TFM_REQ_MASK);
  59         return crypto_skcipher_setkey(child, key, key_len);
  60 }
  61
  62 static int simd_skcipher_encrypt(struct skcipher_request *req)
  63 {
  64         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  65         struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
  66         struct skcipher_request *subreq;
  67         struct crypto_skcipher *child;
  68
  69         subreq = skcipher_request_ctx(req);
  70         *subreq = *req;
  71
  72         if (!crypto_simd_usable() ||
  73             (in_atomic() && cryptd_skcipher_queued(ctx->cryptd_tfm)))
  74                 child = &ctx->cryptd_tfm->base;
  75         else
  76                 child = cryptd_skcipher_child(ctx->cryptd_tfm);
  77
  78         skcipher_request_set_tfm(subreq, child);
  79
  80         return crypto_skcipher_encrypt(subreq);
  81 }
  82
  83 static int simd_skcipher_decrypt(struct skcipher_request *req)
  84 {
  85         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  86         struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
  87         struct skcipher_request *subreq;
  88         struct crypto_skcipher *child;
  89
  90         subreq = skcipher_request_ctx(req);
  91         *subreq = *req;
  92
  93         if (!crypto_simd_usable() ||
  94             (in_atomic() && cryptd_skcipher_queued(ctx->cryptd_tfm)))
  95                 child = &ctx->cryptd_tfm->base;
  96         else
  97                 child = cryptd_skcipher_child(ctx->cryptd_tfm);
  98
  99         skcipher_request_set_tfm(subreq, child);
 100
 101         return crypto_skcipher_decrypt(subreq);
 102 }
 103
 104 static void simd_skcipher_exit(struct crypto_skcipher *tfm)
 105 {
 106         struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
 107
 108         cryptd_free_skcipher(ctx->cryptd_tfm);
 109 }
 110
 111 static int simd_skcipher_init(struct crypto_skcipher *tfm)
 112 {
 113         struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
 114         struct cryptd_skcipher *cryptd_tfm;
 115         struct simd_skcipher_alg *salg;
 116         struct skcipher_alg *alg;
 117         unsigned reqsize;
 118
 119         alg = crypto_skcipher_alg(tfm);
 120         salg = container_of(alg, struct simd_skcipher_alg, alg);
 121
 122         cryptd_tfm = cryptd_alloc_skcipher(salg->ialg_name,
 123                                            CRYPTO_ALG_INTERNAL,
 124                                            CRYPTO_ALG_INTERNAL);
 125         if (IS_ERR(cryptd_tfm))
 126                 return PTR_ERR(cryptd_tfm);
 127
 128         ctx->cryptd_tfm = cryptd_tfm;
 129
 130         reqsize = crypto_skcipher_reqsize(cryptd_skcipher_child(cryptd_tfm));
 131         reqsize = max(reqsize, crypto_skcipher_reqsize(&cryptd_tfm->base));
 132         reqsize += sizeof(struct skcipher_request);
 133
 134         crypto_skcipher_set_reqsize(tfm, reqsize);
 135
 136         return 0;
 137 }
 138
 139 struct simd_skcipher_alg *simd_skcipher_create_compat(const char *algname,
 140                                                       const char *drvname,
 141                                                       const char *basename)
 142 {
 143         struct simd_skcipher_alg *salg;
 144         struct crypto_skcipher *tfm;
 145         struct skcipher_alg *ialg;
 146         struct skcipher_alg *alg;
 147         int err;
 148
 149         tfm = crypto_alloc_skcipher(basename, CRYPTO_ALG_INTERNAL,
 150                                     CRYPTO_ALG_INTERNAL | CRYPTO_ALG_ASYNC);
 151         if (IS_ERR(tfm))
 152                 return ERR_CAST(tfm);
 153
 154         ialg = crypto_skcipher_alg(tfm);
 155
 156         salg = kzalloc(sizeof(*salg), GFP_KERNEL);
 157         if (!salg) {
 158                 salg = ERR_PTR(-ENOMEM);
 159                 goto out_put_tfm;
 160         }
 161
 162         salg->ialg_name = basename;
 163         alg = &salg->alg;
 164
 165         err = -ENAMETOOLONG;
 166         if (snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", algname) >=
 167             CRYPTO_MAX_ALG_NAME)
 168                 goto out_free_salg;
 169
 170         if (snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
 171                      drvname) >= CRYPTO_MAX_ALG_NAME)
 172                 goto out_free_salg;
 173
 174         alg->base.cra_flags = CRYPTO_ALG_ASYNC;
 175         alg->base.cra_priority = ialg->base.cra_priority;
 176         alg->base.cra_blocksize = ialg->base.cra_blocksize;
 177         alg->base.cra_alignmask = ialg->base.cra_alignmask;
 178         alg->base.cra_module = ialg->base.cra_module;
 179         alg->base.cra_ctxsize = sizeof(struct simd_skcipher_ctx);
 180
 181         alg->ivsize = ialg->ivsize;
 182         alg->chunksize = ialg->chunksize;
 183         alg->min_keysize = ialg->min_keysize;
 184         alg->max_keysize = ialg->max_keysize;
 185
 186         alg->init = simd_skcipher_init;
 187         alg->exit = simd_skcipher_exit;
 188
 189         alg->setkey = simd_skcipher_setkey;
 190         alg->encrypt = simd_skcipher_encrypt;
 191         alg->decrypt = simd_skcipher_decrypt;
 192
 193         err = crypto_register_skcipher(alg);
 194         if (err)
 195                 goto out_free_salg;
 196
 197 out_put_tfm:
 198         crypto_free_skcipher(tfm);
 199         return salg;
 200
 201 out_free_salg:
 202         kfree(salg);
 203         salg = ERR_PTR(err);
 204         goto out_put_tfm;
 205 }
 206 EXPORT_SYMBOL_GPL(simd_skcipher_create_compat);
 207
 208 struct simd_skcipher_alg *simd_skcipher_create(const char *algname,
 209                                                const char *basename)
 210 {
 211         char drvname[CRYPTO_MAX_ALG_NAME];
 212
 213         if (snprintf(drvname, CRYPTO_MAX_ALG_NAME, "simd-%s", basename) >=
 214             CRYPTO_MAX_ALG_NAME)
 215                 return ERR_PTR(-ENAMETOOLONG);
 216
 217         return simd_skcipher_create_compat(algname, drvname, basename);
 218 }
 219 EXPORT_SYMBOL_GPL(simd_skcipher_create);
 220
 221 void simd_skcipher_free(struct simd_skcipher_alg *salg)
 222 {
 223         crypto_unregister_skcipher(&salg->alg);
 224         kfree(salg);
 225 }
 226 EXPORT_SYMBOL_GPL(simd_skcipher_free);
 227
 228 int simd_register_skciphers_compat(struct skcipher_alg *algs, int count,
 229                                    struct simd_skcipher_alg **simd_algs)
 230 {
 231         int err;
 232         int i;
 233         const char *algname;
 234         const char *drvname;
 235         const char *basename;
 236         struct simd_skcipher_alg *simd;
 237
 238         err = crypto_register_skciphers(algs, count);
 239         if (err)
 240                 return err;
 241
 242         for (i = 0; i < count; i++) {
 243                 WARN_ON(strncmp(algs[i].base.cra_name, "__", 2));
 244                 WARN_ON(strncmp(algs[i].base.cra_driver_name, "__", 2));
 245                 algname = algs[i].base.cra_name + 2;
 246                 drvname = algs[i].base.cra_driver_name + 2;
 247                 basename = algs[i].base.cra_driver_name;
 248                 simd = simd_skcipher_create_compat(algname, drvname, basename);
 249                 err = PTR_ERR(simd);
 250                 if (IS_ERR(simd))
 251                         goto err_unregister;
 252                 simd_algs[i] = simd;
 253         }
 254         return 0;
 255
 256 err_unregister:
 257         simd_unregister_skciphers(algs, count, simd_algs);
 258         return err;
 259 }
 260 EXPORT_SYMBOL_GPL(simd_register_skciphers_compat);
 261
 262 void simd_unregister_skciphers(struct skcipher_alg *algs, int count,
 263                                struct simd_skcipher_alg **simd_algs)
 264 {
 265         int i;
 266
 267         crypto_unregister_skciphers(algs, count);
 268
 269         for (i = 0; i < count; i++) {
 270                 if (simd_algs[i]) {
 271                         simd_skcipher_free(simd_algs[i]);
 272                         simd_algs[i] = NULL;
 273                 }
 274         }
 275 }
 276 EXPORT_SYMBOL_GPL(simd_unregister_skciphers);
 277
 278 /* AEAD support */
 279
 280 struct simd_aead_alg {
 281         const char *ialg_name;
 282         struct aead_alg alg;
 283 };
 284
 285 struct simd_aead_ctx {
 286         struct cryptd_aead *cryptd_tfm;
 287 };
 288
 289 static int simd_aead_setkey(struct crypto_aead *tfm, const u8 *key,
 290                                 unsigned int key_len)
 291 {
 292         struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
 293         struct crypto_aead *child = &ctx->cryptd_tfm->base;
 294
 295         crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
 296         crypto_aead_set_flags(child, crypto_aead_get_flags(tfm) &
 297                                      CRYPTO_TFM_REQ_MASK);
 298         return crypto_aead_setkey(child, key, key_len);
 299 }
 300
 301 static int simd_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
 302 {
 303         struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
 304         struct crypto_aead *child = &ctx->cryptd_tfm->base;
 305
 306         return crypto_aead_setauthsize(child, authsize);
 307 }
 308
 309 static int simd_aead_encrypt(struct aead_request *req)
 310 {
 311         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 312         struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
 313         struct aead_request *subreq;
 314         struct crypto_aead *child;
 315
 316         subreq = aead_request_ctx(req);
 317         *subreq = *req;
 318
 319         if (!crypto_simd_usable() ||
 320             (in_atomic() && cryptd_aead_queued(ctx->cryptd_tfm)))
 321                 child = &ctx->cryptd_tfm->base;
 322         else
 323                 child = cryptd_aead_child(ctx->cryptd_tfm);
 324
 325         aead_request_set_tfm(subreq, child);
 326
 327         return crypto_aead_encrypt(subreq);
 328 }
 329
 330 static int simd_aead_decrypt(struct aead_request *req)
 331 {
 332         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 333         struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
 334         struct aead_request *subreq;
 335         struct crypto_aead *child;
 336
 337         subreq = aead_request_ctx(req);
 338         *subreq = *req;
 339
 340         if (!crypto_simd_usable() ||
 341             (in_atomic() && cryptd_aead_queued(ctx->cryptd_tfm)))
 342                 child = &ctx->cryptd_tfm->base;
 343         else
 344                 child = cryptd_aead_child(ctx->cryptd_tfm);
 345
 346         aead_request_set_tfm(subreq, child);
 347
 348         return crypto_aead_decrypt(subreq);
 349 }
 350
 351 static void simd_aead_exit(struct crypto_aead *tfm)
 352 {
 353         struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
 354
 355         cryptd_free_aead(ctx->cryptd_tfm);
 356 }
 357
 358 static int simd_aead_init(struct crypto_aead *tfm)
 359 {
 360         struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
 361         struct cryptd_aead *cryptd_tfm;
 362         struct simd_aead_alg *salg;
 363         struct aead_alg *alg;
 364         unsigned reqsize;
 365
 366         alg = crypto_aead_alg(tfm);
 367         salg = container_of(alg, struct simd_aead_alg, alg);
 368
 369         cryptd_tfm = cryptd_alloc_aead(salg->ialg_name, CRYPTO_ALG_INTERNAL,
 370                                        CRYPTO_ALG_INTERNAL);
 371         if (IS_ERR(cryptd_tfm))
 372                 return PTR_ERR(cryptd_tfm);
 373
 374         ctx->cryptd_tfm = cryptd_tfm;
 375
 376         reqsize = crypto_aead_reqsize(cryptd_aead_child(cryptd_tfm));
 377         reqsize = max(reqsize, crypto_aead_reqsize(&cryptd_tfm->base));
 378         reqsize += sizeof(struct aead_request);
 379
 380         crypto_aead_set_reqsize(tfm, reqsize);
 381
 382         return 0;
 383 }
 384
 385 struct simd_aead_alg *simd_aead_create_compat(const char *algname,
 386                                               const char *drvname,
 387                                               const char *basename)
 388 {
 389         struct simd_aead_alg *salg;
 390         struct crypto_aead *tfm;
 391         struct aead_alg *ialg;
 392         struct aead_alg *alg;
 393         int err;
 394
 395         tfm = crypto_alloc_aead(basename, CRYPTO_ALG_INTERNAL,
 396                                 CRYPTO_ALG_INTERNAL | CRYPTO_ALG_ASYNC);
 397         if (IS_ERR(tfm))
 398                 return ERR_CAST(tfm);
 399
 400         ialg = crypto_aead_alg(tfm);
 401
 402         salg = kzalloc(sizeof(*salg), GFP_KERNEL);
 403         if (!salg) {
 404                 salg = ERR_PTR(-ENOMEM);
 405                 goto out_put_tfm;
 406         }
 407
 408         salg->ialg_name = basename;
 409         alg = &salg->alg;
 410
 411         err = -ENAMETOOLONG;
 412         if (snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", algname) >=
 413             CRYPTO_MAX_ALG_NAME)
 414                 goto out_free_salg;
 415
 416         if (snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
 417                      drvname) >= CRYPTO_MAX_ALG_NAME)
 418                 goto out_free_salg;
 419
 420         alg->base.cra_flags = CRYPTO_ALG_ASYNC;
 421         alg->base.cra_priority = ialg->base.cra_priority;
 422         alg->base.cra_blocksize = ialg->base.cra_blocksize;
 423         alg->base.cra_alignmask = ialg->base.cra_alignmask;
 424         alg->base.cra_module = ialg->base.cra_module;
 425         alg->base.cra_ctxsize = sizeof(struct simd_aead_ctx);
 426
 427         alg->ivsize = ialg->ivsize;
 428         alg->maxauthsize = ialg->maxauthsize;
 429         alg->chunksize = ialg->chunksize;
 430
 431         alg->init = simd_aead_init;
 432         alg->exit = simd_aead_exit;
 433
 434         alg->setkey = simd_aead_setkey;
 435         alg->setauthsize = simd_aead_setauthsize;
 436         alg->encrypt = simd_aead_encrypt;
 437         alg->decrypt = simd_aead_decrypt;
 438
 439         err = crypto_register_aead(alg);
 440         if (err)
 441                 goto out_free_salg;
 442
 443 out_put_tfm:
 444         crypto_free_aead(tfm);
 445         return salg;
 446
 447 out_free_salg:
 448         kfree(salg);
 449         salg = ERR_PTR(err);
 450         goto out_put_tfm;
 451 }
 452 EXPORT_SYMBOL_GPL(simd_aead_create_compat);
 453
 454 struct simd_aead_alg *simd_aead_create(const char *algname,
 455                                        const char *basename)
 456 {
 457         char drvname[CRYPTO_MAX_ALG_NAME];
 458
 459         if (snprintf(drvname, CRYPTO_MAX_ALG_NAME, "simd-%s", basename) >=
 460             CRYPTO_MAX_ALG_NAME)
 461                 return ERR_PTR(-ENAMETOOLONG);
 462
 463         return simd_aead_create_compat(algname, drvname, basename);
 464 }
 465 EXPORT_SYMBOL_GPL(simd_aead_create);
 466
 467 void simd_aead_free(struct simd_aead_alg *salg)
 468 {
 469         crypto_unregister_aead(&salg->alg);
 470         kfree(salg);
 471 }
 472 EXPORT_SYMBOL_GPL(simd_aead_free);
 473
 474 int simd_register_aeads_compat(struct aead_alg *algs, int count,
 475                                struct simd_aead_alg **simd_algs)
 476 {
 477         int err;
 478         int i;
 479         const char *algname;
 480         const char *drvname;
 481         const char *basename;
 482         struct simd_aead_alg *simd;
 483
 484         err = crypto_register_aeads(algs, count);
 485         if (err)
 486                 return err;
 487
 488         for (i = 0; i < count; i++) {
 489                 WARN_ON(strncmp(algs[i].base.cra_name, "__", 2));
 490                 WARN_ON(strncmp(algs[i].base.cra_driver_name, "__", 2));
 491                 algname = algs[i].base.cra_name + 2;
 492                 drvname = algs[i].base.cra_driver_name + 2;
 493                 basename = algs[i].base.cra_driver_name;
 494                 simd = simd_aead_create_compat(algname, drvname, basename);
 495                 err = PTR_ERR(simd);
 496                 if (IS_ERR(simd))
 497                         goto err_unregister;
 498                 simd_algs[i] = simd;
 499         }
 500         return 0;
 501
 502 err_unregister:
 503         simd_unregister_aeads(algs, count, simd_algs);
 504         return err;
 505 }
 506 EXPORT_SYMBOL_GPL(simd_register_aeads_compat);
 507
 508 void simd_unregister_aeads(struct aead_alg *algs, int count,
 509                            struct simd_aead_alg **simd_algs)
 510 {
 511         int i;
 512
 513         crypto_unregister_aeads(algs, count);
 514
 515         for (i = 0; i < count; i++) {
 516                 if (simd_algs[i]) {
 517                         simd_aead_free(simd_algs[i]);
 518                         simd_algs[i] = NULL;
 519                 }
 520         }
 521 }
 522 EXPORT_SYMBOL_GPL(simd_unregister_aeads);
 523
 524 MODULE_LICENSE("GPL");