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/atomic.h>
  24 #include <linux/err.h>
  25 #include <linux/init.h>
  26 #include <linux/module.h>
  27 #include <linux/slab.h>
  28 #include <linux/notifier.h>
  29 #include <linux/kobject.h>
  30 #include <linux/cpu.h>
  31 #include <crypto/pcrypt.h>
  32
  33 struct padata_pcrypt {
  34         struct padata_instance *pinst;
  35         struct workqueue_struct *wq;
  36
  37         /*
  38          * Cpumask for callback CPUs. It should be
  39          * equal to serial cpumask of corresponding padata instance,
  40          * so it is updated when padata notifies us about serial
  41          * cpumask change.
  42          *
  43          * cb_cpumask is protected by RCU. This fact prevents us from
  44          * using cpumask_var_t directly because the actual type of
  45          * cpumsak_var_t depends on kernel configuration(particularly on
  46          * CONFIG_CPUMASK_OFFSTACK macro). Depending on the configuration
  47          * cpumask_var_t may be either a pointer to the struct cpumask
  48          * or a variable allocated on the stack. Thus we can not safely use
  49          * cpumask_var_t with RCU operations such as rcu_assign_pointer or
  50          * rcu_dereference. So cpumask_var_t is wrapped with struct
  51          * pcrypt_cpumask which makes possible to use it with RCU.
  52          */
  53         struct pcrypt_cpumask {
  54                 cpumask_var_t mask;
  55         } *cb_cpumask;
  56         struct notifier_block nblock;
  57 };
  58
  59 static struct padata_pcrypt pencrypt;
  60 static struct padata_pcrypt pdecrypt;
  61 static struct kset           *pcrypt_kset;
  62
  63 struct pcrypt_instance_ctx {
  64         struct crypto_aead_spawn spawn;
  65         atomic_t tfm_count;
  66 };
  67
  68 struct pcrypt_aead_ctx {
  69         struct crypto_aead *child;
  70         unsigned int cb_cpu;
  71 };
  72
  73 static int pcrypt_do_parallel(struct padata_priv *padata, unsigned int *cb_cpu,
  74                               struct padata_pcrypt *pcrypt)
  75 {
  76         unsigned int cpu_index, cpu, i;
  77         struct pcrypt_cpumask *cpumask;
  78
  79         cpu = *cb_cpu;
  80
  81         rcu_read_lock_bh();
  82         cpumask = rcu_dereference_bh(pcrypt->cb_cpumask);
  83         if (cpumask_test_cpu(cpu, cpumask->mask))
  84                         goto out;
  85
  86         if (!cpumask_weight(cpumask->mask))
  87                         goto out;
  88
  89         cpu_index = cpu % cpumask_weight(cpumask->mask);
  90
  91         cpu = cpumask_first(cpumask->mask);
  92         for (i = 0; i < cpu_index; i++)
  93                 cpu = cpumask_next(cpu, cpumask->mask);
  94
  95         *cb_cpu = cpu;
  96
  97 out:
  98         rcu_read_unlock_bh();
  99         return padata_do_parallel(pcrypt->pinst, padata, cpu);
 100 }
 101
 102 static int pcrypt_aead_setkey(struct crypto_aead *parent,
 103                               const u8 *key, unsigned int keylen)
 104 {
 105         struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(parent);
 106
 107         return crypto_aead_setkey(ctx->child, key, keylen);
 108 }
 109
 110 static int pcrypt_aead_setauthsize(struct crypto_aead *parent,
 111                                    unsigned int authsize)
 112 {
 113         struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(parent);
 114
 115         return crypto_aead_setauthsize(ctx->child, authsize);
 116 }
 117
 118 static void pcrypt_aead_serial(struct padata_priv *padata)
 119 {
 120         struct pcrypt_request *preq = pcrypt_padata_request(padata);
 121         struct aead_request *req = pcrypt_request_ctx(preq);
 122
 123         aead_request_complete(req->base.data, padata->info);
 124 }
 125
 126 static void pcrypt_aead_giv_serial(struct padata_priv *padata)
 127 {
 128         struct pcrypt_request *preq = pcrypt_padata_request(padata);
 129         struct aead_givcrypt_request *req = pcrypt_request_ctx(preq);
 130
 131         aead_request_complete(req->areq.base.data, padata->info);
 132 }
 133
 134 static void pcrypt_aead_done(struct crypto_async_request *areq, int err)
 135 {
 136         struct aead_request *req = areq->data;
 137         struct pcrypt_request *preq = aead_request_ctx(req);
 138         struct padata_priv *padata = pcrypt_request_padata(preq);
 139
 140         padata->info = err;
 141         req->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
 142
 143         padata_do_serial(padata);
 144 }
 145
 146 static void pcrypt_aead_enc(struct padata_priv *padata)
 147 {
 148         struct pcrypt_request *preq = pcrypt_padata_request(padata);
 149         struct aead_request *req = pcrypt_request_ctx(preq);
 150
 151         padata->info = crypto_aead_encrypt(req);
 152
 153         if (padata->info == -EINPROGRESS)
 154                 return;
 155
 156         padata_do_serial(padata);
 157 }
 158
 159 static int pcrypt_aead_encrypt(struct aead_request *req)
 160 {
 161         int err;
 162         struct pcrypt_request *preq = aead_request_ctx(req);
 163         struct aead_request *creq = pcrypt_request_ctx(preq);
 164         struct padata_priv *padata = pcrypt_request_padata(preq);
 165         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 166         struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(aead);
 167         u32 flags = aead_request_flags(req);
 168
 169         memset(padata, 0, sizeof(struct padata_priv));
 170
 171         padata->parallel = pcrypt_aead_enc;
 172         padata->serial = pcrypt_aead_serial;
 173
 174         aead_request_set_tfm(creq, ctx->child);
 175         aead_request_set_callback(creq, flags & ~CRYPTO_TFM_REQ_MAY_SLEEP,
 176                                   pcrypt_aead_done, req);
 177         aead_request_set_crypt(creq, req->src, req->dst,
 178                                req->cryptlen, req->iv);
 179         aead_request_set_assoc(creq, req->assoc, req->assoclen);
 180
 181         err = pcrypt_do_parallel(padata, &ctx->cb_cpu, &pencrypt);
 182         if (!err)
 183                 return -EINPROGRESS;
 184
 185         return err;
 186 }
 187
 188 static void pcrypt_aead_dec(struct padata_priv *padata)
 189 {
 190         struct pcrypt_request *preq = pcrypt_padata_request(padata);
 191         struct aead_request *req = pcrypt_request_ctx(preq);
 192
 193         padata->info = crypto_aead_decrypt(req);
 194
 195         if (padata->info == -EINPROGRESS)
 196                 return;
 197
 198         padata_do_serial(padata);
 199 }
 200
 201 static int pcrypt_aead_decrypt(struct aead_request *req)
 202 {
 203         int err;
 204         struct pcrypt_request *preq = aead_request_ctx(req);
 205         struct aead_request *creq = pcrypt_request_ctx(preq);
 206         struct padata_priv *padata = pcrypt_request_padata(preq);
 207         struct crypto_aead *aead = crypto_aead_reqtfm(req);
 208         struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(aead);
 209         u32 flags = aead_request_flags(req);
 210
 211         memset(padata, 0, sizeof(struct padata_priv));
 212
 213         padata->parallel = pcrypt_aead_dec;
 214         padata->serial = pcrypt_aead_serial;
 215
 216         aead_request_set_tfm(creq, ctx->child);
 217         aead_request_set_callback(creq, flags & ~CRYPTO_TFM_REQ_MAY_SLEEP,
 218                                   pcrypt_aead_done, req);
 219         aead_request_set_crypt(creq, req->src, req->dst,
 220                                req->cryptlen, req->iv);
 221         aead_request_set_assoc(creq, req->assoc, req->assoclen);
 222
 223         err = pcrypt_do_parallel(padata, &ctx->cb_cpu, &pdecrypt);
 224         if (!err)
 225                 return -EINPROGRESS;
 226
 227         return err;
 228 }
 229
 230 static void pcrypt_aead_givenc(struct padata_priv *padata)
 231 {
 232         struct pcrypt_request *preq = pcrypt_padata_request(padata);
 233         struct aead_givcrypt_request *req = pcrypt_request_ctx(preq);
 234
 235         padata->info = crypto_aead_givencrypt(req);
 236
 237         if (padata->info == -EINPROGRESS)
 238                 return;
 239
 240         padata_do_serial(padata);
 241 }
 242
 243 static int pcrypt_aead_givencrypt(struct aead_givcrypt_request *req)
 244 {
 245         int err;
 246         struct aead_request *areq = &req->areq;
 247         struct pcrypt_request *preq = aead_request_ctx(areq);
 248         struct aead_givcrypt_request *creq = pcrypt_request_ctx(preq);
 249         struct padata_priv *padata = pcrypt_request_padata(preq);
 250         struct crypto_aead *aead = aead_givcrypt_reqtfm(req);
 251         struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(aead);
 252         u32 flags = aead_request_flags(areq);
 253
 254         memset(padata, 0, sizeof(struct padata_priv));
 255
 256         padata->parallel = pcrypt_aead_givenc;
 257         padata->serial = pcrypt_aead_giv_serial;
 258
 259         aead_givcrypt_set_tfm(creq, ctx->child);
 260         aead_givcrypt_set_callback(creq, flags & ~CRYPTO_TFM_REQ_MAY_SLEEP,
 261                                    pcrypt_aead_done, areq);
 262         aead_givcrypt_set_crypt(creq, areq->src, areq->dst,
 263                                 areq->cryptlen, areq->iv);
 264         aead_givcrypt_set_assoc(creq, areq->assoc, areq->assoclen);
 265         aead_givcrypt_set_giv(creq, req->giv, req->seq);
 266
 267         err = pcrypt_do_parallel(padata, &ctx->cb_cpu, &pencrypt);
 268         if (!err)
 269                 return -EINPROGRESS;
 270
 271         return err;
 272 }
 273
 274 static int pcrypt_aead_init_tfm(struct crypto_tfm *tfm)
 275 {
 276         int cpu, cpu_index;
 277         struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
 278         struct pcrypt_instance_ctx *ictx = crypto_instance_ctx(inst);
 279         struct pcrypt_aead_ctx *ctx = crypto_tfm_ctx(tfm);
 280         struct crypto_aead *cipher;
 281
 282         cpu_index = (unsigned int)atomic_inc_return(&ictx->tfm_count) %
 283                     cpumask_weight(cpu_online_mask);
 284
 285         ctx->cb_cpu = cpumask_first(cpu_online_mask);
 286         for (cpu = 0; cpu < cpu_index; cpu++)
 287                 ctx->cb_cpu = cpumask_next(ctx->cb_cpu, cpu_online_mask);
 288
 289         cipher = crypto_spawn_aead(crypto_instance_ctx(inst));
 290
 291         if (IS_ERR(cipher))
 292                 return PTR_ERR(cipher);
 293
 294         ctx->child = cipher;
 295         crypto_aead_set_reqsize(__crypto_aead_cast(tfm),
 296                 sizeof(struct pcrypt_request) +
 297                 sizeof(struct aead_givcrypt_request) +
 298                 crypto_aead_reqsize(cipher));
 299
 300         return 0;
 301 }
 302
 303 static void pcrypt_aead_exit_tfm(struct crypto_tfm *tfm)
 304 {
 305         struct pcrypt_aead_ctx *ctx = crypto_tfm_ctx(tfm);
 306
 307         crypto_free_aead(ctx->child);
 308 }
 309
 310 static int pcrypt_init_instance(struct crypto_instance *inst,
 311                                 struct crypto_alg *alg)
 312 {
 313         if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
 314                      "pcrypt(%s)", alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
 315                 return -ENAMETOOLONG;
 316
 317         memcpy(inst->alg.cra_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
 318
 319         inst->alg.cra_priority = alg->cra_priority + 100;
 320         inst->alg.cra_blocksize = alg->cra_blocksize;
 321         inst->alg.cra_alignmask = alg->cra_alignmask;
 322
 323         return 0;
 324 }
 325
 326 static struct crypto_instance *pcrypt_alloc_aead(struct rtattr **tb,
 327                                                  u32 type, u32 mask)
 328 {
 329         struct pcrypt_instance_ctx *ctx;
 330         struct crypto_instance *inst;
 331         struct crypto_alg *alg;
 332         const char *name;
 333         int err;
 334
 335         name = crypto_attr_alg_name(tb[1]);
 336         if (IS_ERR(name))
 337                 return ERR_CAST(name);
 338
 339         inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
 340         if (!inst)
 341                 return ERR_PTR(-ENOMEM);
 342
 343         ctx = crypto_instance_ctx(inst);
 344         crypto_set_aead_spawn(&ctx->spawn, inst);
 345
 346         err = crypto_grab_aead(&ctx->spawn, name, 0, 0);
 347         if (err)
 348                 goto out_free_inst;
 349
 350         alg = crypto_aead_spawn_alg(&ctx->spawn);
 351         err = pcrypt_init_instance(inst, alg);
 352         if (err)
 353                 goto out_drop_aead;
 354
 355         inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_ASYNC;
 356         inst->alg.cra_type = &crypto_aead_type;
 357
 358         inst->alg.cra_aead.ivsize = alg->cra_aead.ivsize;
 359         inst->alg.cra_aead.geniv = alg->cra_aead.geniv;
 360         inst->alg.cra_aead.maxauthsize = alg->cra_aead.maxauthsize;
 361
 362         inst->alg.cra_ctxsize = sizeof(struct pcrypt_aead_ctx);
 363
 364         inst->alg.cra_init = pcrypt_aead_init_tfm;
 365         inst->alg.cra_exit = pcrypt_aead_exit_tfm;
 366
 367         inst->alg.cra_aead.setkey = pcrypt_aead_setkey;
 368         inst->alg.cra_aead.setauthsize = pcrypt_aead_setauthsize;
 369         inst->alg.cra_aead.encrypt = pcrypt_aead_encrypt;
 370         inst->alg.cra_aead.decrypt = pcrypt_aead_decrypt;
 371         inst->alg.cra_aead.givencrypt = pcrypt_aead_givencrypt;
 372
 373 out:
 374         return inst;
 375
 376 out_drop_aead:
 377         crypto_drop_aead(&ctx->spawn);
 378 out_free_inst:
 379         kfree(inst);
 380         inst = ERR_PTR(err);
 381         goto out;
 382 }
 383
 384 static struct crypto_instance *pcrypt_alloc(struct rtattr **tb)
 385 {
 386         struct crypto_attr_type *algt;
 387
 388         algt = crypto_get_attr_type(tb);
 389         if (IS_ERR(algt))
 390                 return ERR_CAST(algt);
 391
 392         switch (algt->type & algt->mask & CRYPTO_ALG_TYPE_MASK) {
 393         case CRYPTO_ALG_TYPE_AEAD:
 394                 return pcrypt_alloc_aead(tb, algt->type, algt->mask);
 395         }
 396
 397         return ERR_PTR(-EINVAL);
 398 }
 399
 400 static void pcrypt_free(struct crypto_instance *inst)
 401 {
 402         struct pcrypt_instance_ctx *ctx = crypto_instance_ctx(inst);
 403
 404         crypto_drop_aead(&ctx->spawn);
 405         kfree(inst);
 406 }
 407
 408 static int pcrypt_cpumask_change_notify(struct notifier_block *self,
 409                                         unsigned long val, void *data)
 410 {
 411         struct padata_pcrypt *pcrypt;
 412         struct pcrypt_cpumask *new_mask, *old_mask;
 413         struct padata_cpumask *cpumask = (struct padata_cpumask *)data;
 414
 415         if (!(val & PADATA_CPU_SERIAL))
 416                 return 0;
 417
 418         pcrypt = container_of(self, struct padata_pcrypt, nblock);
 419         new_mask = kmalloc(sizeof(*new_mask), GFP_KERNEL);
 420         if (!new_mask)
 421                 return -ENOMEM;
 422         if (!alloc_cpumask_var(&new_mask->mask, GFP_KERNEL)) {
 423                 kfree(new_mask);
 424                 return -ENOMEM;
 425         }
 426
 427         old_mask = pcrypt->cb_cpumask;
 428
 429         cpumask_copy(new_mask->mask, cpumask->cbcpu);
 430         rcu_assign_pointer(pcrypt->cb_cpumask, new_mask);
 431         synchronize_rcu_bh();
 432
 433         free_cpumask_var(old_mask->mask);
 434         kfree(old_mask);
 435         return 0;
 436 }
 437
 438 static int pcrypt_sysfs_add(struct padata_instance *pinst, const char *name)
 439 {
 440         int ret;
 441
 442         pinst->kobj.kset = pcrypt_kset;
 443         ret = kobject_add(&pinst->kobj, NULL, name);
 444         if (!ret)
 445                 kobject_uevent(&pinst->kobj, KOBJ_ADD);
 446
 447         return ret;
 448 }
 449
 450 static int pcrypt_init_padata(struct padata_pcrypt *pcrypt,
 451                               const char *name)
 452 {
 453         int ret = -ENOMEM;
 454         struct pcrypt_cpumask *mask;
 455
 456         get_online_cpus();
 457
 458         pcrypt->wq = alloc_workqueue("%s", WQ_MEM_RECLAIM | WQ_CPU_INTENSIVE,
 459                                      1, name);
 460         if (!pcrypt->wq)
 461                 goto err;
 462
 463         pcrypt->pinst = padata_alloc_possible(pcrypt->wq);
 464         if (!pcrypt->pinst)
 465                 goto err_destroy_workqueue;
 466
 467         mask = kmalloc(sizeof(*mask), GFP_KERNEL);
 468         if (!mask)
 469                 goto err_free_padata;
 470         if (!alloc_cpumask_var(&mask->mask, GFP_KERNEL)) {
 471                 kfree(mask);
 472                 goto err_free_padata;
 473         }
 474
 475         cpumask_and(mask->mask, cpu_possible_mask, cpu_online_mask);
 476         rcu_assign_pointer(pcrypt->cb_cpumask, mask);
 477
 478         pcrypt->nblock.notifier_call = pcrypt_cpumask_change_notify;
 479         ret = padata_register_cpumask_notifier(pcrypt->pinst, &pcrypt->nblock);
 480         if (ret)
 481                 goto err_free_cpumask;
 482
 483         ret = pcrypt_sysfs_add(pcrypt->pinst, name);
 484         if (ret)
 485                 goto err_unregister_notifier;
 486
 487         put_online_cpus();
 488
 489         return ret;
 490
 491 err_unregister_notifier:
 492         padata_unregister_cpumask_notifier(pcrypt->pinst, &pcrypt->nblock);
 493 err_free_cpumask:
 494         free_cpumask_var(mask->mask);
 495         kfree(mask);
 496 err_free_padata:
 497         padata_free(pcrypt->pinst);
 498 err_destroy_workqueue:
 499         destroy_workqueue(pcrypt->wq);
 500 err:
 501         put_online_cpus();
 502
 503         return ret;
 504 }
 505
 506 static void pcrypt_fini_padata(struct padata_pcrypt *pcrypt)
 507 {
 508         free_cpumask_var(pcrypt->cb_cpumask->mask);
 509         kfree(pcrypt->cb_cpumask);
 510
 511         padata_stop(pcrypt->pinst);
 512         padata_unregister_cpumask_notifier(pcrypt->pinst, &pcrypt->nblock);
 513         destroy_workqueue(pcrypt->wq);
 514         padata_free(pcrypt->pinst);
 515 }
 516
 517 static struct crypto_template pcrypt_tmpl = {
 518         .name = "pcrypt",
 519         .alloc = pcrypt_alloc,
 520         .free = pcrypt_free,
 521         .module = THIS_MODULE,
 522 };
 523
 524 static int __init pcrypt_init(void)
 525 {
 526         int err = -ENOMEM;
 527
 528         pcrypt_kset = kset_create_and_add("pcrypt", NULL, kernel_kobj);
 529         if (!pcrypt_kset)
 530                 goto err;
 531
 532         err = pcrypt_init_padata(&pencrypt, "pencrypt");
 533         if (err)
 534                 goto err_unreg_kset;
 535
 536         err = pcrypt_init_padata(&pdecrypt, "pdecrypt");
 537         if (err)
 538                 goto err_deinit_pencrypt;
 539
 540         padata_start(pencrypt.pinst);
 541         padata_start(pdecrypt.pinst);
 542
 543         return crypto_register_template(&pcrypt_tmpl);
 544
 545 err_deinit_pencrypt:
 546         pcrypt_fini_padata(&pencrypt);
 547 err_unreg_kset:
 548         kset_unregister(pcrypt_kset);
 549 err:
 550         return err;
 551 }
 552
 553 static void __exit pcrypt_exit(void)
 554 {
 555         pcrypt_fini_padata(&pencrypt);
 556         pcrypt_fini_padata(&pdecrypt);
 557
 558         kset_unregister(pcrypt_kset);
 559         crypto_unregister_template(&pcrypt_tmpl);
 560 }
 561
 562 module_init(pcrypt_init);
 563 module_exit(pcrypt_exit);
 564
 565 MODULE_LICENSE("GPL");
 566 MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
 567 MODULE_DESCRIPTION("Parallel crypto wrapper");
 568 MODULE_ALIAS_CRYPTO("pcrypt");