crypto/pcrypt.c

   1 /*
   2  * pcrypt - Parallel crypto wrapper.
   3  *
   4  * Copyright (C) 2009 secunet Security Networks AG
   5  * Copyright (C) 2009 Steffen Klassert <steffen.klassert@secunet.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms and conditions of the GNU General Public License,
   9  * version 2, as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14  * more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along with
  17  * this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #include <crypto/algapi.h>
  22 #include <crypto/internal/aead.h>
  23 #include <linux/err.h>
  24 #include <linux/init.h>
  25 #include <linux/module.h>
  26 #include <linux/slab.h>
  27 #include <linux/notifier.h>
  28 #include <crypto/pcrypt.h>
  29
  30 struct pcrypt_instance {
  31         struct padata_instance *pinst;
  32         struct workqueue_struct *wq;
  33
  34         /*
  35          * Cpumask for callback CPUs. It should be
  36          * equal to serial cpumask of corresponding padata instance,
  37          * so it is updated when padata notifies us about serial
  38          * cpumask change.
  39          *
  40          * cb_cpumask is protected by RCU. This fact prevents us from
  41          * using cpumask_var_t directly because the actual type of
  42          * cpumsak_var_t depends on kernel configuration(particularly on
  43          * CONFIG_CPUMASK_OFFSTACK macro). Depending on the configuration
  44          * cpumask_var_t may be either a pointer to the struct cpumask
  45          * or a variable allocated on the stack. Thus we can not safely use
  46          * cpumask_var_t with RCU operations such as rcu_assign_pointer or
  47          * rcu_dereference. So cpumask_var_t is wrapped with struct
  48          * pcrypt_cpumask which makes possible to use it with RCU.
  49          */
  50         struct pcrypt_cpumask {
  51                 cpumask_var_t mask;
  52         } *cb_cpumask;
  53         struct notifier_block nblock;
  54 };
  55
  56 static struct pcrypt_instance pencrypt;
  57 static struct pcrypt_instance pdecrypt;
  58
  59
  60 struct pcrypt_instance_ctx {
  61         struct crypto_spawn spawn;
  62         unsigned int tfm_count;
  63 };
  64
  65 struct pcrypt_aead_ctx {
  66         struct crypto_aead *child;
  67         unsigned int cb_cpu;
  68 };
  69
  70 static int pcrypt_do_parallel(struct padata_priv *padata, unsigned int *cb_cpu,
  71                               struct pcrypt_instance *pcrypt)
  72 {
  73         unsigned int cpu_index, cpu, i;
  74         struct pcrypt_cpumask *cpumask;
  75
  76         cpu = *cb_cpu;
  77
  78         rcu_read_lock_bh();
  79         cpumask = rcu_dereference(pcrypt->cb_cpumask);
  80         if (cpumask_test_cpu(cpu, cpumask->mask))
  81                         goto out;
  82
  83         cpu_index = cpu % cpumask_weight(cpumask->mask);
  84
  85         cpu = cpumask_first(cpumask->mask);
  86         for (i = 0; i < cpu_index; i++)
  87                 cpu = cpumask_next(cpu, cpumask->mask);
  88
  89         *cb_cpu = cpu;
  90
  91 out:
  92         rcu_read_unlock_bh();
  93         return padata_do_parallel(pcrypt->pinst, padata, cpu);
  94 }
  95
  96 static int pcrypt_aead_setkey(struct crypto_aead *parent,
  97                               const u8 *key, unsigned int keylen)
  98 {
  99         struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(parent);
 100
 101         return crypto_aead_setkey(ctx->child, key, keylen);
 102 }
 103
 104 static int pcrypt_aead_setauthsize(struct crypto_aead *parent,
 105                                    unsigned int authsize)
 106 {
 107         struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(parent);
 108
 109         return crypto_aead_setauthsize(ctx->child, authsize);
 110 }
 111
 112 static void pcrypt_aead_serial(struct padata_priv *padata)
 113 {
 114         struct pcrypt_request *preq = pcrypt_padata_request(padata);
 115         struct aead_request *req = pcrypt_request_ctx(preq);
 116
 117         aead_request_complete(req->base.data, padata->info);
 118 }
 119
 120 static void pcrypt_aead_giv_serial(struct padata_priv *padata)
 121 {
 122         struct pcrypt_request *preq = pcrypt_padata_request(padata);
 123         struct aead_givcrypt_request *req = pcrypt_request_ctx(preq);
 124
 125         aead_request_complete(req->areq.base.data, padata->info);
 126 }
 127
 128 static void pcrypt_aead_done(struct crypto_async_request *areq, int err)
 129 {
 130         struct aead_request *req = areq->data;
 131         struct pcrypt_request *preq = aead_request_ctx(req);
 132         struct padata_priv *padata = pcrypt_request_padata(preq);
 133
 134         padata->info = err;
 135         req->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
 136
 137         padata_do_serial(padata);
 138 }
 139
 140 static void pcrypt_aead_enc(struct padata_priv *padata)
 141 {
 142         struct pcrypt_request *preq = pcrypt_padata_request(padata);
 143         struct aead_request *req = pcrypt_request_ctx(preq);
 144
 145         padata->info = crypto_aead_encrypt(req);
 146
 147         if (padata->info == -EINPROGRESS)
 148                 return;
 149
 150         padata_do_serial(padata);
 151 }
 152
 153 static int pcrypt_aead_encrypt(struct aead_request *req)
 154 {
 155         int err;
 156         struct pcrypt_request *preq = aead_request_ctx(req);
 157         struct aead_request *creq = pcrypt_request_ctx(preq);
 158         struct padata_priv *padata = pcrypt_request_padata(preq);
 159         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 160         struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(aead);
 161         u32 flags = aead_request_flags(req);
 162
 163         memset(padata, 0, sizeof(struct padata_priv));
 164
 165         padata->parallel = pcrypt_aead_enc;
 166         padata->serial = pcrypt_aead_serial;
 167
 168         aead_request_set_tfm(creq, ctx->child);
 169         aead_request_set_callback(creq, flags & ~CRYPTO_TFM_REQ_MAY_SLEEP,
 170                                   pcrypt_aead_done, req);
 171         aead_request_set_crypt(creq, req->src, req->dst,
 172                                req->cryptlen, req->iv);
 173         aead_request_set_assoc(creq, req->assoc, req->assoclen);
 174
 175         err = pcrypt_do_parallel(padata, &ctx->cb_cpu, &pencrypt);
 176         if (!err)
 177                 return -EINPROGRESS;
 178
 179         return err;
 180 }
 181
 182 static void pcrypt_aead_dec(struct padata_priv *padata)
 183 {
 184         struct pcrypt_request *preq = pcrypt_padata_request(padata);
 185         struct aead_request *req = pcrypt_request_ctx(preq);
 186
 187         padata->info = crypto_aead_decrypt(req);
 188
 189         if (padata->info == -EINPROGRESS)
 190                 return;
 191
 192         padata_do_serial(padata);
 193 }
 194
 195 static int pcrypt_aead_decrypt(struct aead_request *req)
 196 {
 197         int err;
 198         struct pcrypt_request *preq = aead_request_ctx(req);
 199         struct aead_request *creq = pcrypt_request_ctx(preq);
 200         struct padata_priv *padata = pcrypt_request_padata(preq);
 201         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 202         struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(aead);
 203         u32 flags = aead_request_flags(req);
 204
 205         memset(padata, 0, sizeof(struct padata_priv));
 206
 207         padata->parallel = pcrypt_aead_dec;
 208         padata->serial = pcrypt_aead_serial;
 209
 210         aead_request_set_tfm(creq, ctx->child);
 211         aead_request_set_callback(creq, flags & ~CRYPTO_TFM_REQ_MAY_SLEEP,
 212                                   pcrypt_aead_done, req);
 213         aead_request_set_crypt(creq, req->src, req->dst,
 214                                req->cryptlen, req->iv);
 215         aead_request_set_assoc(creq, req->assoc, req->assoclen);
 216
 217         err = pcrypt_do_parallel(padata, &ctx->cb_cpu, &pdecrypt);
 218         if (!err)
 219                 return -EINPROGRESS;
 220
 221         return err;
 222 }
 223
 224 static void pcrypt_aead_givenc(struct padata_priv *padata)
 225 {
 226         struct pcrypt_request *preq = pcrypt_padata_request(padata);
 227         struct aead_givcrypt_request *req = pcrypt_request_ctx(preq);
 228
 229         padata->info = crypto_aead_givencrypt(req);
 230
 231         if (padata->info == -EINPROGRESS)
 232                 return;
 233
 234         padata_do_serial(padata);
 235 }
 236
 237 static int pcrypt_aead_givencrypt(struct aead_givcrypt_request *req)
 238 {
 239         int err;
 240         struct aead_request *areq = &req->areq;
 241         struct pcrypt_request *preq = aead_request_ctx(areq);
 242         struct aead_givcrypt_request *creq = pcrypt_request_ctx(preq);
 243         struct padata_priv *padata = pcrypt_request_padata(preq);
 244         struct crypto_aead *aead = aead_givcrypt_reqtfm(req);
 245         struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(aead);
 246         u32 flags = aead_request_flags(areq);
 247
 248         memset(padata, 0, sizeof(struct padata_priv));
 249
 250         padata->parallel = pcrypt_aead_givenc;
 251         padata->serial = pcrypt_aead_giv_serial;
 252
 253         aead_givcrypt_set_tfm(creq, ctx->child);
 254         aead_givcrypt_set_callback(creq, flags & ~CRYPTO_TFM_REQ_MAY_SLEEP,
 255                                    pcrypt_aead_done, areq);
 256         aead_givcrypt_set_crypt(creq, areq->src, areq->dst,
 257                                 areq->cryptlen, areq->iv);
 258         aead_givcrypt_set_assoc(creq, areq->assoc, areq->assoclen);
 259         aead_givcrypt_set_giv(creq, req->giv, req->seq);
 260
 261         err = pcrypt_do_parallel(padata, &ctx->cb_cpu, &pencrypt);
 262         if (!err)
 263                 return -EINPROGRESS;
 264
 265         return err;
 266 }
 267
 268 static int pcrypt_aead_init_tfm(struct crypto_tfm *tfm)
 269 {
 270         int cpu, cpu_index;
 271         struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
 272         struct pcrypt_instance_ctx *ictx = crypto_instance_ctx(inst);
 273         struct pcrypt_aead_ctx *ctx = crypto_tfm_ctx(tfm);
 274         struct crypto_aead *cipher;
 275
 276         ictx->tfm_count++;
 277
 278         cpu_index = ictx->tfm_count % cpumask_weight(cpu_active_mask);
 279
 280         ctx->cb_cpu = cpumask_first(cpu_active_mask);
 281         for (cpu = 0; cpu < cpu_index; cpu++)
 282                 ctx->cb_cpu = cpumask_next(ctx->cb_cpu, cpu_active_mask);
 283
 284         cipher = crypto_spawn_aead(crypto_instance_ctx(inst));
 285
 286         if (IS_ERR(cipher))
 287                 return PTR_ERR(cipher);
 288
 289         ctx->child = cipher;
 290         tfm->crt_aead.reqsize = sizeof(struct pcrypt_request)
 291                 + sizeof(struct aead_givcrypt_request)
 292                 + crypto_aead_reqsize(cipher);
 293
 294         return 0;
 295 }
 296
 297 static void pcrypt_aead_exit_tfm(struct crypto_tfm *tfm)
 298 {
 299         struct pcrypt_aead_ctx *ctx = crypto_tfm_ctx(tfm);
 300
 301         crypto_free_aead(ctx->child);
 302 }
 303
 304 static struct crypto_instance *pcrypt_alloc_instance(struct crypto_alg *alg)
 305 {
 306         struct crypto_instance *inst;
 307         struct pcrypt_instance_ctx *ctx;
 308         int err;
 309
 310         inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
 311         if (!inst) {
 312                 inst = ERR_PTR(-ENOMEM);
 313                 goto out;
 314         }
 315
 316         err = -ENAMETOOLONG;
 317         if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
 318                      "pcrypt(%s)", alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
 319                 goto out_free_inst;
 320
 321         memcpy(inst->alg.cra_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
 322
 323         ctx = crypto_instance_ctx(inst);
 324         err = crypto_init_spawn(&ctx->spawn, alg, inst,
 325                                 CRYPTO_ALG_TYPE_MASK);
 326         if (err)
 327                 goto out_free_inst;
 328
 329         inst->alg.cra_priority = alg->cra_priority + 100;
 330         inst->alg.cra_blocksize = alg->cra_blocksize;
 331         inst->alg.cra_alignmask = alg->cra_alignmask;
 332
 333 out:
 334         return inst;
 335
 336 out_free_inst:
 337         kfree(inst);
 338         inst = ERR_PTR(err);
 339         goto out;
 340 }
 341
 342 static struct crypto_instance *pcrypt_alloc_aead(struct rtattr **tb,
 343                                                  u32 type, u32 mask)
 344 {
 345         struct crypto_instance *inst;
 346         struct crypto_alg *alg;
 347
 348         alg = crypto_get_attr_alg(tb, type, (mask & CRYPTO_ALG_TYPE_MASK));
 349         if (IS_ERR(alg))
 350                 return ERR_CAST(alg);
 351
 352         inst = pcrypt_alloc_instance(alg);
 353         if (IS_ERR(inst))
 354                 goto out_put_alg;
 355
 356         inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_ASYNC;
 357         inst->alg.cra_type = &crypto_aead_type;
 358
 359         inst->alg.cra_aead.ivsize = alg->cra_aead.ivsize;
 360         inst->alg.cra_aead.geniv = alg->cra_aead.geniv;
 361         inst->alg.cra_aead.maxauthsize = alg->cra_aead.maxauthsize;
 362
 363         inst->alg.cra_ctxsize = sizeof(struct pcrypt_aead_ctx);
 364
 365         inst->alg.cra_init = pcrypt_aead_init_tfm;
 366         inst->alg.cra_exit = pcrypt_aead_exit_tfm;
 367
 368         inst->alg.cra_aead.setkey = pcrypt_aead_setkey;
 369         inst->alg.cra_aead.setauthsize = pcrypt_aead_setauthsize;
 370         inst->alg.cra_aead.encrypt = pcrypt_aead_encrypt;
 371         inst->alg.cra_aead.decrypt = pcrypt_aead_decrypt;
 372         inst->alg.cra_aead.givencrypt = pcrypt_aead_givencrypt;
 373
 374 out_put_alg:
 375         crypto_mod_put(alg);
 376         return inst;
 377 }
 378
 379 static struct crypto_instance *pcrypt_alloc(struct rtattr **tb)
 380 {
 381         struct crypto_attr_type *algt;
 382
 383         algt = crypto_get_attr_type(tb);
 384         if (IS_ERR(algt))
 385                 return ERR_CAST(algt);
 386
 387         switch (algt->type & algt->mask & CRYPTO_ALG_TYPE_MASK) {
 388         case CRYPTO_ALG_TYPE_AEAD:
 389                 return pcrypt_alloc_aead(tb, algt->type, algt->mask);
 390         }
 391
 392         return ERR_PTR(-EINVAL);
 393 }
 394
 395 static void pcrypt_free(struct crypto_instance *inst)
 396 {
 397         struct pcrypt_instance_ctx *ctx = crypto_instance_ctx(inst);
 398
 399         crypto_drop_spawn(&ctx->spawn);
 400         kfree(inst);
 401 }
 402
 403 static int pcrypt_cpumask_change_notify(struct notifier_block *self,
 404                                         unsigned long val, void *data)
 405 {
 406         struct pcrypt_instance *pcrypt;
 407         struct pcrypt_cpumask *new_mask, *old_mask;
 408
 409         if (!(val & PADATA_CPU_SERIAL))
 410                 return 0;
 411
 412         pcrypt = container_of(self, struct pcrypt_instance, nblock);
 413         new_mask = kmalloc(sizeof(*new_mask), GFP_KERNEL);
 414         if (!new_mask)
 415                 return -ENOMEM;
 416         if (!alloc_cpumask_var(&new_mask->mask, GFP_KERNEL)) {
 417                 kfree(new_mask);
 418                 return -ENOMEM;
 419         }
 420
 421         old_mask = pcrypt->cb_cpumask;
 422
 423         padata_get_cpumask(pcrypt->pinst, PADATA_CPU_SERIAL, new_mask->mask);
 424         rcu_assign_pointer(pcrypt->cb_cpumask, new_mask);
 425         synchronize_rcu_bh();
 426
 427         free_cpumask_var(old_mask->mask);
 428         kfree(old_mask);
 429         return 0;
 430 }
 431
 432 static int __pcrypt_init_instance(struct pcrypt_instance *pcrypt,
 433                                   const char *name)
 434 {
 435         int ret = -ENOMEM;
 436         struct pcrypt_cpumask *mask;
 437
 438         pcrypt->wq = create_workqueue(name);
 439         if (!pcrypt->wq)
 440                 goto err;
 441
 442         pcrypt->pinst = padata_alloc(pcrypt->wq);
 443         if (!pcrypt->pinst)
 444                 goto err_destroy_workqueue;
 445
 446         mask = kmalloc(sizeof(*mask), GFP_KERNEL);
 447         if (!mask)
 448                 goto err_free_padata;
 449         if (!alloc_cpumask_var(&mask->mask, GFP_KERNEL)) {
 450                 kfree(mask);
 451                 goto err_free_padata;
 452         }
 453
 454         padata_get_cpumask(pcrypt->pinst, PADATA_CPU_SERIAL, mask->mask);
 455         rcu_assign_pointer(pcrypt->cb_cpumask, mask);
 456
 457         pcrypt->nblock.notifier_call = pcrypt_cpumask_change_notify;
 458         ret = padata_register_cpumask_notifier(pcrypt->pinst, &pcrypt->nblock);
 459         if (ret)
 460                 goto err_free_cpumask;
 461
 462         return ret;
 463 err_free_cpumask:
 464         free_cpumask_var(mask->mask);
 465         kfree(mask);
 466 err_free_padata:
 467         padata_free(pcrypt->pinst);
 468 err_destroy_workqueue:
 469         destroy_workqueue(pcrypt->wq);
 470 err:
 471         return ret;
 472 }
 473
 474 static void __pcrypt_deinit_instance(struct pcrypt_instance *pcrypt)
 475 {
 476         free_cpumask_var(pcrypt->cb_cpumask->mask);
 477         kfree(pcrypt->cb_cpumask);
 478
 479         padata_stop(pcrypt->pinst);
 480         padata_unregister_cpumask_notifier(pcrypt->pinst, &pcrypt->nblock);
 481         destroy_workqueue(pcrypt->wq);
 482         padata_free(pcrypt->pinst);
 483 }
 484
 485 static struct crypto_template pcrypt_tmpl = {
 486         .name = "pcrypt",
 487         .alloc = pcrypt_alloc,
 488         .free = pcrypt_free,
 489         .module = THIS_MODULE,
 490 };
 491
 492 static int __init pcrypt_init(void)
 493 {
 494         int err;
 495
 496         err = __pcrypt_init_instance(&pencrypt, "pencrypt");
 497         if (err)
 498                 goto err;
 499
 500         err = __pcrypt_init_instance(&pdecrypt, "pdecrypt");
 501         if (err)
 502                 goto err_deinit_pencrypt;
 503
 504         padata_start(pencrypt.pinst);
 505         padata_start(pdecrypt.pinst);
 506
 507         return crypto_register_template(&pcrypt_tmpl);
 508
 509 err_deinit_pencrypt:
 510         __pcrypt_deinit_instance(&pencrypt);
 511 err:
 512         return err;
 513 }
 514
 515 static void __exit pcrypt_exit(void)
 516 {
 517         __pcrypt_deinit_instance(&pencrypt);
 518         __pcrypt_deinit_instance(&pdecrypt);
 519
 520         crypto_unregister_template(&pcrypt_tmpl);
 521 }
 522
 523 module_init(pcrypt_init);
 524 module_exit(pcrypt_exit);
 525
 526 MODULE_LICENSE("GPL");
 527 MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
 528 MODULE_DESCRIPTION("Parallel crypto wrapper");