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