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
pcrypt_do_parallel(struct padata_priv * padata,unsigned int * cb_cpu,struct padata_pcrypt * pcrypt)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
pcrypt_aead_setkey(struct crypto_aead * parent,const u8 * key,unsigned int keylen)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
pcrypt_aead_setauthsize(struct crypto_aead * parent,unsigned int authsize)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
pcrypt_aead_serial(struct padata_priv * padata)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
pcrypt_aead_done(struct crypto_async_request * areq,int err)126 static void pcrypt_aead_done(struct crypto_async_request *areq, int err)
127 {
128 struct aead_request *req = areq->data;
129 struct pcrypt_request *preq = aead_request_ctx(req);
130 struct padata_priv *padata = pcrypt_request_padata(preq);
131
132 padata->info = err;
133
134 padata_do_serial(padata);
135 }
136
pcrypt_aead_enc(struct padata_priv * padata)137 static void pcrypt_aead_enc(struct padata_priv *padata)
138 {
139 struct pcrypt_request *preq = pcrypt_padata_request(padata);
140 struct aead_request *req = pcrypt_request_ctx(preq);
141 int ret;
142
143 ret = crypto_aead_encrypt(req);
144
145 if (ret == -EINPROGRESS)
146 return;
147
148 padata->info = ret;
149 padata_do_serial(padata);
150 }
151
pcrypt_aead_encrypt(struct aead_request * req)152 static int pcrypt_aead_encrypt(struct aead_request *req)
153 {
154 int err;
155 struct pcrypt_request *preq = aead_request_ctx(req);
156 struct aead_request *creq = pcrypt_request_ctx(preq);
157 struct padata_priv *padata = pcrypt_request_padata(preq);
158 struct crypto_aead *aead = crypto_aead_reqtfm(req);
159 struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(aead);
160 u32 flags = aead_request_flags(req);
161
162 memset(padata, 0, sizeof(struct padata_priv));
163
164 padata->parallel = pcrypt_aead_enc;
165 padata->serial = pcrypt_aead_serial;
166
167 aead_request_set_tfm(creq, ctx->child);
168 aead_request_set_callback(creq, flags & ~CRYPTO_TFM_REQ_MAY_SLEEP,
169 pcrypt_aead_done, req);
170 aead_request_set_crypt(creq, req->src, req->dst,
171 req->cryptlen, req->iv);
172 aead_request_set_ad(creq, req->assoclen);
173
174 err = pcrypt_do_parallel(padata, &ctx->cb_cpu, &pencrypt);
175 if (!err)
176 return -EINPROGRESS;
177
178 return err;
179 }
180
pcrypt_aead_dec(struct padata_priv * padata)181 static void pcrypt_aead_dec(struct padata_priv *padata)
182 {
183 struct pcrypt_request *preq = pcrypt_padata_request(padata);
184 struct aead_request *req = pcrypt_request_ctx(preq);
185 int ret;
186
187 ret = crypto_aead_decrypt(req);
188
189 if (ret == -EINPROGRESS)
190 return;
191
192 padata->info = ret;
193 padata_do_serial(padata);
194 }
195
pcrypt_aead_decrypt(struct aead_request * req)196 static int pcrypt_aead_decrypt(struct aead_request *req)
197 {
198 int err;
199 struct pcrypt_request *preq = aead_request_ctx(req);
200 struct aead_request *creq = pcrypt_request_ctx(preq);
201 struct padata_priv *padata = pcrypt_request_padata(preq);
202 struct crypto_aead *aead = crypto_aead_reqtfm(req);
203 struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(aead);
204 u32 flags = aead_request_flags(req);
205
206 memset(padata, 0, sizeof(struct padata_priv));
207
208 padata->parallel = pcrypt_aead_dec;
209 padata->serial = pcrypt_aead_serial;
210
211 aead_request_set_tfm(creq, ctx->child);
212 aead_request_set_callback(creq, flags & ~CRYPTO_TFM_REQ_MAY_SLEEP,
213 pcrypt_aead_done, req);
214 aead_request_set_crypt(creq, req->src, req->dst,
215 req->cryptlen, req->iv);
216 aead_request_set_ad(creq, req->assoclen);
217
218 err = pcrypt_do_parallel(padata, &ctx->cb_cpu, &pdecrypt);
219 if (!err)
220 return -EINPROGRESS;
221
222 return err;
223 }
224
pcrypt_aead_init_tfm(struct crypto_aead * tfm)225 static int pcrypt_aead_init_tfm(struct crypto_aead *tfm)
226 {
227 int cpu, cpu_index;
228 struct aead_instance *inst = aead_alg_instance(tfm);
229 struct pcrypt_instance_ctx *ictx = aead_instance_ctx(inst);
230 struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(tfm);
231 struct crypto_aead *cipher;
232
233 cpu_index = (unsigned int)atomic_inc_return(&ictx->tfm_count) %
234 cpumask_weight(cpu_online_mask);
235
236 ctx->cb_cpu = cpumask_first(cpu_online_mask);
237 for (cpu = 0; cpu < cpu_index; cpu++)
238 ctx->cb_cpu = cpumask_next(ctx->cb_cpu, cpu_online_mask);
239
240 cipher = crypto_spawn_aead(&ictx->spawn);
241
242 if (IS_ERR(cipher))
243 return PTR_ERR(cipher);
244
245 ctx->child = cipher;
246 crypto_aead_set_reqsize(tfm, sizeof(struct pcrypt_request) +
247 sizeof(struct aead_request) +
248 crypto_aead_reqsize(cipher));
249
250 return 0;
251 }
252
pcrypt_aead_exit_tfm(struct crypto_aead * tfm)253 static void pcrypt_aead_exit_tfm(struct crypto_aead *tfm)
254 {
255 struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(tfm);
256
257 crypto_free_aead(ctx->child);
258 }
259
pcrypt_free(struct aead_instance * inst)260 static void pcrypt_free(struct aead_instance *inst)
261 {
262 struct pcrypt_instance_ctx *ctx = aead_instance_ctx(inst);
263
264 crypto_drop_aead(&ctx->spawn);
265 kfree(inst);
266 }
267
pcrypt_init_instance(struct crypto_instance * inst,struct crypto_alg * alg)268 static int pcrypt_init_instance(struct crypto_instance *inst,
269 struct crypto_alg *alg)
270 {
271 if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
272 "pcrypt(%s)", alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
273 return -ENAMETOOLONG;
274
275 memcpy(inst->alg.cra_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
276
277 inst->alg.cra_priority = alg->cra_priority + 100;
278 inst->alg.cra_blocksize = alg->cra_blocksize;
279 inst->alg.cra_alignmask = alg->cra_alignmask;
280
281 return 0;
282 }
283
pcrypt_create_aead(struct crypto_template * tmpl,struct rtattr ** tb,u32 type,u32 mask)284 static int pcrypt_create_aead(struct crypto_template *tmpl, struct rtattr **tb,
285 u32 type, u32 mask)
286 {
287 struct pcrypt_instance_ctx *ctx;
288 struct crypto_attr_type *algt;
289 struct aead_instance *inst;
290 struct aead_alg *alg;
291 const char *name;
292 int err;
293
294 algt = crypto_get_attr_type(tb);
295 if (IS_ERR(algt))
296 return PTR_ERR(algt);
297
298 name = crypto_attr_alg_name(tb[1]);
299 if (IS_ERR(name))
300 return PTR_ERR(name);
301
302 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
303 if (!inst)
304 return -ENOMEM;
305
306 ctx = aead_instance_ctx(inst);
307 crypto_set_aead_spawn(&ctx->spawn, aead_crypto_instance(inst));
308
309 err = crypto_grab_aead(&ctx->spawn, name, 0, 0);
310 if (err)
311 goto out_free_inst;
312
313 alg = crypto_spawn_aead_alg(&ctx->spawn);
314 err = pcrypt_init_instance(aead_crypto_instance(inst), &alg->base);
315 if (err)
316 goto out_drop_aead;
317
318 inst->alg.base.cra_flags = CRYPTO_ALG_ASYNC;
319
320 inst->alg.ivsize = crypto_aead_alg_ivsize(alg);
321 inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
322
323 inst->alg.base.cra_ctxsize = sizeof(struct pcrypt_aead_ctx);
324
325 inst->alg.init = pcrypt_aead_init_tfm;
326 inst->alg.exit = pcrypt_aead_exit_tfm;
327
328 inst->alg.setkey = pcrypt_aead_setkey;
329 inst->alg.setauthsize = pcrypt_aead_setauthsize;
330 inst->alg.encrypt = pcrypt_aead_encrypt;
331 inst->alg.decrypt = pcrypt_aead_decrypt;
332
333 inst->free = pcrypt_free;
334
335 err = aead_register_instance(tmpl, inst);
336 if (err)
337 goto out_drop_aead;
338
339 out:
340 return err;
341
342 out_drop_aead:
343 crypto_drop_aead(&ctx->spawn);
344 out_free_inst:
345 kfree(inst);
346 goto out;
347 }
348
pcrypt_create(struct crypto_template * tmpl,struct rtattr ** tb)349 static int pcrypt_create(struct crypto_template *tmpl, struct rtattr **tb)
350 {
351 struct crypto_attr_type *algt;
352
353 algt = crypto_get_attr_type(tb);
354 if (IS_ERR(algt))
355 return PTR_ERR(algt);
356
357 switch (algt->type & algt->mask & CRYPTO_ALG_TYPE_MASK) {
358 case CRYPTO_ALG_TYPE_AEAD:
359 return pcrypt_create_aead(tmpl, tb, algt->type, algt->mask);
360 }
361
362 return -EINVAL;
363 }
364
pcrypt_cpumask_change_notify(struct notifier_block * self,unsigned long val,void * data)365 static int pcrypt_cpumask_change_notify(struct notifier_block *self,
366 unsigned long val, void *data)
367 {
368 struct padata_pcrypt *pcrypt;
369 struct pcrypt_cpumask *new_mask, *old_mask;
370 struct padata_cpumask *cpumask = (struct padata_cpumask *)data;
371
372 if (!(val & PADATA_CPU_SERIAL))
373 return 0;
374
375 pcrypt = container_of(self, struct padata_pcrypt, nblock);
376 new_mask = kmalloc(sizeof(*new_mask), GFP_KERNEL);
377 if (!new_mask)
378 return -ENOMEM;
379 if (!alloc_cpumask_var(&new_mask->mask, GFP_KERNEL)) {
380 kfree(new_mask);
381 return -ENOMEM;
382 }
383
384 old_mask = pcrypt->cb_cpumask;
385
386 cpumask_copy(new_mask->mask, cpumask->cbcpu);
387 rcu_assign_pointer(pcrypt->cb_cpumask, new_mask);
388 synchronize_rcu_bh();
389
390 free_cpumask_var(old_mask->mask);
391 kfree(old_mask);
392 return 0;
393 }
394
pcrypt_sysfs_add(struct padata_instance * pinst,const char * name)395 static int pcrypt_sysfs_add(struct padata_instance *pinst, const char *name)
396 {
397 int ret;
398
399 pinst->kobj.kset = pcrypt_kset;
400 ret = kobject_add(&pinst->kobj, NULL, "%s", name);
401 if (!ret)
402 kobject_uevent(&pinst->kobj, KOBJ_ADD);
403
404 return ret;
405 }
406
pcrypt_init_padata(struct padata_pcrypt * pcrypt,const char * name)407 static int pcrypt_init_padata(struct padata_pcrypt *pcrypt,
408 const char *name)
409 {
410 int ret = -ENOMEM;
411 struct pcrypt_cpumask *mask;
412
413 get_online_cpus();
414
415 pcrypt->wq = alloc_workqueue("%s", WQ_MEM_RECLAIM | WQ_CPU_INTENSIVE,
416 1, name);
417 if (!pcrypt->wq)
418 goto err;
419
420 pcrypt->pinst = padata_alloc_possible(pcrypt->wq);
421 if (!pcrypt->pinst)
422 goto err_destroy_workqueue;
423
424 mask = kmalloc(sizeof(*mask), GFP_KERNEL);
425 if (!mask)
426 goto err_free_padata;
427 if (!alloc_cpumask_var(&mask->mask, GFP_KERNEL)) {
428 kfree(mask);
429 goto err_free_padata;
430 }
431
432 cpumask_and(mask->mask, cpu_possible_mask, cpu_online_mask);
433 rcu_assign_pointer(pcrypt->cb_cpumask, mask);
434
435 pcrypt->nblock.notifier_call = pcrypt_cpumask_change_notify;
436 ret = padata_register_cpumask_notifier(pcrypt->pinst, &pcrypt->nblock);
437 if (ret)
438 goto err_free_cpumask;
439
440 ret = pcrypt_sysfs_add(pcrypt->pinst, name);
441 if (ret)
442 goto err_unregister_notifier;
443
444 put_online_cpus();
445
446 return ret;
447
448 err_unregister_notifier:
449 padata_unregister_cpumask_notifier(pcrypt->pinst, &pcrypt->nblock);
450 err_free_cpumask:
451 free_cpumask_var(mask->mask);
452 kfree(mask);
453 err_free_padata:
454 padata_free(pcrypt->pinst);
455 err_destroy_workqueue:
456 destroy_workqueue(pcrypt->wq);
457 err:
458 put_online_cpus();
459
460 return ret;
461 }
462
pcrypt_fini_padata(struct padata_pcrypt * pcrypt)463 static void pcrypt_fini_padata(struct padata_pcrypt *pcrypt)
464 {
465 free_cpumask_var(pcrypt->cb_cpumask->mask);
466 kfree(pcrypt->cb_cpumask);
467
468 padata_stop(pcrypt->pinst);
469 padata_unregister_cpumask_notifier(pcrypt->pinst, &pcrypt->nblock);
470 destroy_workqueue(pcrypt->wq);
471 padata_free(pcrypt->pinst);
472 }
473
474 static struct crypto_template pcrypt_tmpl = {
475 .name = "pcrypt",
476 .create = pcrypt_create,
477 .module = THIS_MODULE,
478 };
479
pcrypt_init(void)480 static int __init pcrypt_init(void)
481 {
482 int err = -ENOMEM;
483
484 pcrypt_kset = kset_create_and_add("pcrypt", NULL, kernel_kobj);
485 if (!pcrypt_kset)
486 goto err;
487
488 err = pcrypt_init_padata(&pencrypt, "pencrypt");
489 if (err)
490 goto err_unreg_kset;
491
492 err = pcrypt_init_padata(&pdecrypt, "pdecrypt");
493 if (err)
494 goto err_deinit_pencrypt;
495
496 padata_start(pencrypt.pinst);
497 padata_start(pdecrypt.pinst);
498
499 return crypto_register_template(&pcrypt_tmpl);
500
501 err_deinit_pencrypt:
502 pcrypt_fini_padata(&pencrypt);
503 err_unreg_kset:
504 kset_unregister(pcrypt_kset);
505 err:
506 return err;
507 }
508
pcrypt_exit(void)509 static void __exit pcrypt_exit(void)
510 {
511 crypto_unregister_template(&pcrypt_tmpl);
512
513 pcrypt_fini_padata(&pencrypt);
514 pcrypt_fini_padata(&pdecrypt);
515
516 kset_unregister(pcrypt_kset);
517 }
518
519 module_init(pcrypt_init);
520 module_exit(pcrypt_exit);
521
522 MODULE_LICENSE("GPL");
523 MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
524 MODULE_DESCRIPTION("Parallel crypto wrapper");
525 MODULE_ALIAS_CRYPTO("pcrypt");
526