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 <jussi.kivilinna@mbnet.fi>
   6  * Copyright (c) 2016 Herbert Xu <herbert@gondor.apana.org.au>
   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 <ying.huang@intel.com>
  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(struct skcipher_alg *ialg,
 140                                                       const char *algname,
 141                                                       const char *drvname,
 142                                                       const char *basename)
 143 {
 144         struct simd_skcipher_alg *salg;
 145         struct skcipher_alg *alg;
 146         int err;
 147
 148         salg = kzalloc(sizeof(*salg), GFP_KERNEL);
 149         if (!salg) {
 150                 salg = ERR_PTR(-ENOMEM);
 151                 goto out;
 152         }
 153
 154         salg->ialg_name = basename;
 155         alg = &salg->alg;
 156
 157         err = -ENAMETOOLONG;
 158         if (snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", algname) >=
 159             CRYPTO_MAX_ALG_NAME)
 160                 goto out_free_salg;
 161
 162         if (snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
 163                      drvname) >= CRYPTO_MAX_ALG_NAME)
 164                 goto out_free_salg;
 165
 166         alg->base.cra_flags = CRYPTO_ALG_ASYNC |
 167                 (ialg->base.cra_flags & CRYPTO_ALG_INHERITED_FLAGS);
 168         alg->base.cra_priority = ialg->base.cra_priority;
 169         alg->base.cra_blocksize = ialg->base.cra_blocksize;
 170         alg->base.cra_alignmask = ialg->base.cra_alignmask;
 171         alg->base.cra_module = ialg->base.cra_module;
 172         alg->base.cra_ctxsize = sizeof(struct simd_skcipher_ctx);
 173
 174         alg->ivsize = ialg->ivsize;
 175         alg->chunksize = ialg->chunksize;
 176         alg->min_keysize = ialg->min_keysize;
 177         alg->max_keysize = ialg->max_keysize;
 178
 179         alg->init = simd_skcipher_init;
 180         alg->exit = simd_skcipher_exit;
 181
 182         alg->setkey = simd_skcipher_setkey;
 183         alg->encrypt = simd_skcipher_encrypt;
 184         alg->decrypt = simd_skcipher_decrypt;
 185
 186         err = crypto_register_skcipher(alg);
 187         if (err)
 188                 goto out_free_salg;
 189
 190 out:
 191         return salg;
 192
 193 out_free_salg:
 194         kfree(salg);
 195         salg = ERR_PTR(err);
 196         goto out;
 197 }
 198 EXPORT_SYMBOL_GPL(simd_skcipher_create_compat);
 199
 200 void simd_skcipher_free(struct simd_skcipher_alg *salg)
 201 {
 202         crypto_unregister_skcipher(&salg->alg);
 203         kfree(salg);
 204 }
 205 EXPORT_SYMBOL_GPL(simd_skcipher_free);
 206
 207 int simd_register_skciphers_compat(struct skcipher_alg *algs, int count,
 208                                    struct simd_skcipher_alg **simd_algs)
 209 {
 210         int err;
 211         int i;
 212         const char *algname;
 213         const char *drvname;
 214         const char *basename;
 215         struct simd_skcipher_alg *simd;
 216
 217         err = crypto_register_skciphers(algs, count);
 218         if (err)
 219                 return err;
 220
 221         for (i = 0; i < count; i++) {
 222                 WARN_ON(strncmp(algs[i].base.cra_name, "__", 2));
 223                 WARN_ON(strncmp(algs[i].base.cra_driver_name, "__", 2));
 224                 algname = algs[i].base.cra_name + 2;
 225                 drvname = algs[i].base.cra_driver_name + 2;
 226                 basename = algs[i].base.cra_driver_name;
 227                 simd = simd_skcipher_create_compat(algs + i, algname, drvname, basename);
 228                 err = PTR_ERR(simd);
 229                 if (IS_ERR(simd))
 230                         goto err_unregister;
 231                 simd_algs[i] = simd;
 232         }
 233         return 0;
 234
 235 err_unregister:
 236         simd_unregister_skciphers(algs, count, simd_algs);
 237         return err;
 238 }
 239 EXPORT_SYMBOL_GPL(simd_register_skciphers_compat);
 240
 241 void simd_unregister_skciphers(struct skcipher_alg *algs, int count,
 242                                struct simd_skcipher_alg **simd_algs)
 243 {
 244         int i;
 245
 246         crypto_unregister_skciphers(algs, count);
 247
 248         for (i = 0; i < count; i++) {
 249                 if (simd_algs[i]) {
 250                         simd_skcipher_free(simd_algs[i]);
 251                         simd_algs[i] = NULL;
 252                 }
 253         }
 254 }
 255 EXPORT_SYMBOL_GPL(simd_unregister_skciphers);
 256
 257 /* AEAD support */
 258
 259 struct simd_aead_alg {
 260         const char *ialg_name;
 261         struct aead_alg alg;
 262 };
 263
 264 struct simd_aead_ctx {
 265         struct cryptd_aead *cryptd_tfm;
 266 };
 267
 268 static int simd_aead_setkey(struct crypto_aead *tfm, const u8 *key,
 269                                 unsigned int key_len)
 270 {
 271         struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
 272         struct crypto_aead *child = &ctx->cryptd_tfm->base;
 273
 274         crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
 275         crypto_aead_set_flags(child, crypto_aead_get_flags(tfm) &
 276                                      CRYPTO_TFM_REQ_MASK);
 277         return crypto_aead_setkey(child, key, key_len);
 278 }
 279
 280 static int simd_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
 281 {
 282         struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
 283         struct crypto_aead *child = &ctx->cryptd_tfm->base;
 284
 285         return crypto_aead_setauthsize(child, authsize);
 286 }
 287
 288 static int simd_aead_encrypt(struct aead_request *req)
 289 {
 290         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 291         struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
 292         struct aead_request *subreq;
 293         struct crypto_aead *child;
 294
 295         subreq = aead_request_ctx(req);
 296         *subreq = *req;
 297
 298         if (!crypto_simd_usable() ||
 299             (in_atomic() && cryptd_aead_queued(ctx->cryptd_tfm)))
 300                 child = &ctx->cryptd_tfm->base;
 301         else
 302                 child = cryptd_aead_child(ctx->cryptd_tfm);
 303
 304         aead_request_set_tfm(subreq, child);
 305
 306         return crypto_aead_encrypt(subreq);
 307 }
 308
 309 static int simd_aead_decrypt(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_decrypt(subreq);
 328 }
 329
 330 static void simd_aead_exit(struct crypto_aead *tfm)
 331 {
 332         struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
 333
 334         cryptd_free_aead(ctx->cryptd_tfm);
 335 }
 336
 337 static int simd_aead_init(struct crypto_aead *tfm)
 338 {
 339         struct simd_aead_ctx *ctx = crypto_aead_ctx(tfm);
 340         struct cryptd_aead *cryptd_tfm;
 341         struct simd_aead_alg *salg;
 342         struct aead_alg *alg;
 343         unsigned reqsize;
 344
 345         alg = crypto_aead_alg(tfm);
 346         salg = container_of(alg, struct simd_aead_alg, alg);
 347
 348         cryptd_tfm = cryptd_alloc_aead(salg->ialg_name, CRYPTO_ALG_INTERNAL,
 349                                        CRYPTO_ALG_INTERNAL);
 350         if (IS_ERR(cryptd_tfm))
 351                 return PTR_ERR(cryptd_tfm);
 352
 353         ctx->cryptd_tfm = cryptd_tfm;
 354
 355         reqsize = crypto_aead_reqsize(cryptd_aead_child(cryptd_tfm));
 356         reqsize = max(reqsize, crypto_aead_reqsize(&cryptd_tfm->base));
 357         reqsize += sizeof(struct aead_request);
 358
 359         crypto_aead_set_reqsize(tfm, reqsize);
 360
 361         return 0;
 362 }
 363
 364 static struct simd_aead_alg *simd_aead_create_compat(struct aead_alg *ialg,
 365                                                      const char *algname,
 366                                                      const char *drvname,
 367                                                      const char *basename)
 368 {
 369         struct simd_aead_alg *salg;
 370         struct aead_alg *alg;
 371         int err;
 372
 373         salg = kzalloc(sizeof(*salg), GFP_KERNEL);
 374         if (!salg) {
 375                 salg = ERR_PTR(-ENOMEM);
 376                 goto out;
 377         }
 378
 379         salg->ialg_name = basename;
 380         alg = &salg->alg;
 381
 382         err = -ENAMETOOLONG;
 383         if (snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", algname) >=
 384             CRYPTO_MAX_ALG_NAME)
 385                 goto out_free_salg;
 386
 387         if (snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
 388                      drvname) >= CRYPTO_MAX_ALG_NAME)
 389                 goto out_free_salg;
 390
 391         alg->base.cra_flags = CRYPTO_ALG_ASYNC |
 392                 (ialg->base.cra_flags & CRYPTO_ALG_INHERITED_FLAGS);
 393         alg->base.cra_priority = ialg->base.cra_priority;
 394         alg->base.cra_blocksize = ialg->base.cra_blocksize;
 395         alg->base.cra_alignmask = ialg->base.cra_alignmask;
 396         alg->base.cra_module = ialg->base.cra_module;
 397         alg->base.cra_ctxsize = sizeof(struct simd_aead_ctx);
 398
 399         alg->ivsize = ialg->ivsize;
 400         alg->maxauthsize = ialg->maxauthsize;
 401         alg->chunksize = ialg->chunksize;
 402
 403         alg->init = simd_aead_init;
 404         alg->exit = simd_aead_exit;
 405
 406         alg->setkey = simd_aead_setkey;
 407         alg->setauthsize = simd_aead_setauthsize;
 408         alg->encrypt = simd_aead_encrypt;
 409         alg->decrypt = simd_aead_decrypt;
 410
 411         err = crypto_register_aead(alg);
 412         if (err)
 413                 goto out_free_salg;
 414
 415 out:
 416         return salg;
 417
 418 out_free_salg:
 419         kfree(salg);
 420         salg = ERR_PTR(err);
 421         goto out;
 422 }
 423
 424 static void simd_aead_free(struct simd_aead_alg *salg)
 425 {
 426         crypto_unregister_aead(&salg->alg);
 427         kfree(salg);
 428 }
 429
 430 int simd_register_aeads_compat(struct aead_alg *algs, int count,
 431                                struct simd_aead_alg **simd_algs)
 432 {
 433         int err;
 434         int i;
 435         const char *algname;
 436         const char *drvname;
 437         const char *basename;
 438         struct simd_aead_alg *simd;
 439
 440         err = crypto_register_aeads(algs, count);
 441         if (err)
 442                 return err;
 443
 444         for (i = 0; i < count; i++) {
 445                 WARN_ON(strncmp(algs[i].base.cra_name, "__", 2));
 446                 WARN_ON(strncmp(algs[i].base.cra_driver_name, "__", 2));
 447                 algname = algs[i].base.cra_name + 2;
 448                 drvname = algs[i].base.cra_driver_name + 2;
 449                 basename = algs[i].base.cra_driver_name;
 450                 simd = simd_aead_create_compat(algs + i, algname, drvname, basename);
 451                 err = PTR_ERR(simd);
 452                 if (IS_ERR(simd))
 453                         goto err_unregister;
 454                 simd_algs[i] = simd;
 455         }
 456         return 0;
 457
 458 err_unregister:
 459         simd_unregister_aeads(algs, count, simd_algs);
 460         return err;
 461 }
 462 EXPORT_SYMBOL_GPL(simd_register_aeads_compat);
 463
 464 void simd_unregister_aeads(struct aead_alg *algs, int count,
 465                            struct simd_aead_alg **simd_algs)
 466 {
 467         int i;
 468
 469         crypto_unregister_aeads(algs, count);
 470
 471         for (i = 0; i < count; i++) {
 472                 if (simd_algs[i]) {
 473                         simd_aead_free(simd_algs[i]);
 474                         simd_algs[i] = NULL;
 475                 }
 476         }
 477 }
 478 EXPORT_SYMBOL_GPL(simd_unregister_aeads);
 479
 480 MODULE_DESCRIPTION("Shared crypto SIMD helpers");
 481 MODULE_LICENSE("GPL");