summaryrefslogtreecommitdiffstats
path: root/crypto/pcrypt.c
blob: 001a3a3e75dfd152c4687bc5b70eb0e60ce2faf8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
/*
 * pcrypt - Parallel crypto wrapper.
 *
 * Copyright (C) 2009 secunet Security Networks AG
 * Copyright (C) 2009 Steffen Klassert <steffen.klassert@secunet.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <crypto/algapi.h>
#include <crypto/internal/aead.h>
#include <linux/atomic.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/notifier.h>
#include <linux/kobject.h>
#include <linux/cpu.h>
#include <crypto/pcrypt.h>

struct padata_pcrypt {
	struct padata_instance *pinst;
	struct workqueue_struct *wq;

	/*
	 * Cpumask for callback CPUs. It should be
	 * equal to serial cpumask of corresponding padata instance,
	 * so it is updated when padata notifies us about serial
	 * cpumask change.
	 *
	 * cb_cpumask is protected by RCU. This fact prevents us from
	 * using cpumask_var_t directly because the actual type of
	 * cpumsak_var_t depends on kernel configuration(particularly on
	 * CONFIG_CPUMASK_OFFSTACK macro). Depending on the configuration
	 * cpumask_var_t may be either a pointer to the struct cpumask
	 * or a variable allocated on the stack. Thus we can not safely use
	 * cpumask_var_t with RCU operations such as rcu_assign_pointer or
	 * rcu_dereference. So cpumask_var_t is wrapped with struct
	 * pcrypt_cpumask which makes possible to use it with RCU.
	 */
	struct pcrypt_cpumask {
		cpumask_var_t mask;
	} *cb_cpumask;
	struct notifier_block nblock;
};

static struct padata_pcrypt pencrypt;
static struct padata_pcrypt pdecrypt;
static struct kset           *pcrypt_kset;

struct pcrypt_instance_ctx {
	struct crypto_aead_spawn spawn;
	atomic_t tfm_count;
};

struct pcrypt_aead_ctx {
	struct crypto_aead *child;
	unsigned int cb_cpu;
};

static int pcrypt_do_parallel(struct padata_priv *padata, unsigned int *cb_cpu,
			      struct padata_pcrypt *pcrypt)
{
	unsigned int cpu_index, cpu, i;
	struct pcrypt_cpumask *cpumask;

	cpu = *cb_cpu;

	rcu_read_lock_bh();
	cpumask = rcu_dereference_bh(pcrypt->cb_cpumask);
	if (cpumask_test_cpu(cpu, cpumask->mask))
			goto out;

	if (!cpumask_weight(cpumask->mask))
			goto out;

	cpu_index = cpu % cpumask_weight(cpumask->mask);

	cpu = cpumask_first(cpumask->mask);
	for (i = 0; i < cpu_index; i++)
		cpu = cpumask_next(cpu, cpumask->mask);

	*cb_cpu = cpu;

out:
	rcu_read_unlock_bh();
	return padata_do_parallel(pcrypt->pinst, padata, cpu);
}

static int pcrypt_aead_setkey(struct crypto_aead *parent,
			      const u8 *key, unsigned int keylen)
{
	struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(parent);

	return crypto_aead_setkey(ctx->child, key, keylen);
}

static int pcrypt_aead_setauthsize(struct crypto_aead *parent,
				   unsigned int authsize)
{
	struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(parent);

	return crypto_aead_setauthsize(ctx->child, authsize);
}

static void pcrypt_aead_serial(struct padata_priv *padata)
{
	struct pcrypt_request *preq = pcrypt_padata_request(padata);
	struct aead_request *req = pcrypt_request_ctx(preq);

	aead_request_complete(req->base.data, padata->info);
}

static void pcrypt_aead_done(struct crypto_async_request *areq, int err)
{
	struct aead_request *req = areq->data;
	struct pcrypt_request *preq = aead_request_ctx(req);
	struct padata_priv *padata = pcrypt_request_padata(preq);

	padata->info = err;
	req->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;

	padata_do_serial(padata);
}

static void pcrypt_aead_enc(struct padata_priv *padata)
{
	struct pcrypt_request *preq = pcrypt_padata_request(padata);
	struct aead_request *req = pcrypt_request_ctx(preq);

	padata->info = crypto_aead_encrypt(req);

	if (padata->info == -EINPROGRESS)
		return;

	padata_do_serial(padata);
}

static int pcrypt_aead_encrypt(struct aead_request *req)
{
	int err;
	struct pcrypt_request *preq = aead_request_ctx(req);
	struct aead_request *creq = pcrypt_request_ctx(preq);
	struct padata_priv *padata = pcrypt_request_padata(preq);
	struct crypto_aead *aead = crypto_aead_reqtfm(req);
	struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(aead);
	u32 flags = aead_request_flags(req);

	memset(padata, 0, sizeof(struct padata_priv));

	padata->parallel = pcrypt_aead_enc;
	padata->serial = pcrypt_aead_serial;

	aead_request_set_tfm(creq, ctx->child);
	aead_request_set_callback(creq, flags & ~CRYPTO_TFM_REQ_MAY_SLEEP,
				  pcrypt_aead_done, req);
	aead_request_set_crypt(creq, req->src, req->dst,
			       req->cryptlen, req->iv);
	aead_request_set_ad(creq, req->assoclen);

	err = pcrypt_do_parallel(padata, &ctx->cb_cpu, &pencrypt);
	if (!err)
		return -EINPROGRESS;

	return err;
}

static void pcrypt_aead_dec(struct padata_priv *padata)
{
	struct pcrypt_request *preq = pcrypt_padata_request(padata);
	struct aead_request *req = pcrypt_request_ctx(preq);

	padata->info = crypto_aead_decrypt(req);

	if (padata->info == -EINPROGRESS)
		return;

	padata_do_serial(padata);
}

static int pcrypt_aead_decrypt(struct aead_request *req)
{
	int err;
	struct pcrypt_request *preq = aead_request_ctx(req);
	struct aead_request *creq = pcrypt_request_ctx(preq);
	struct padata_priv *padata = pcrypt_request_padata(preq);
	struct crypto_aead *aead = crypto_aead_reqtfm(req);
	struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(aead);
	u32 flags = aead_request_flags(req);

	memset(padata, 0, sizeof(struct padata_priv));

	padata->parallel = pcrypt_aead_dec;
	padata->serial = pcrypt_aead_serial;

	aead_request_set_tfm(creq, ctx->child);
	aead_request_set_callback(creq, flags & ~CRYPTO_TFM_REQ_MAY_SLEEP,
				  pcrypt_aead_done, req);
	aead_request_set_crypt(creq, req->src, req->dst,
			       req->cryptlen, req->iv);
	aead_request_set_ad(creq, req->assoclen);

	err = pcrypt_do_parallel(padata, &ctx->cb_cpu, &pdecrypt);
	if (!err)
		return -EINPROGRESS;

	return err;
}

static int pcrypt_aead_init_tfm(struct crypto_aead *tfm)
{
	int cpu, cpu_index;
	struct aead_instance *inst = aead_alg_instance(tfm);
	struct pcrypt_instance_ctx *ictx = aead_instance_ctx(inst);
	struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(tfm);
	struct crypto_aead *cipher;

	cpu_index = (unsigned int)atomic_inc_return(&ictx->tfm_count) %
		    cpumask_weight(cpu_online_mask);

	ctx->cb_cpu = cpumask_first(cpu_online_mask);
	for (cpu = 0; cpu < cpu_index; cpu++)
		ctx->cb_cpu = cpumask_next(ctx->cb_cpu, cpu_online_mask);

	cipher = crypto_spawn_aead(&ictx->spawn);

	if (IS_ERR(cipher))
		return PTR_ERR(cipher);

	ctx->child = cipher;
	crypto_aead_set_reqsize(tfm, sizeof(struct pcrypt_request) +
				     sizeof(struct aead_request) +
				     crypto_aead_reqsize(cipher));

	return 0;
}

static void pcrypt_aead_exit_tfm(struct crypto_aead *tfm)
{
	struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(tfm);

	crypto_free_aead(ctx->child);
}

static int pcrypt_init_instance(struct crypto_instance *inst,
				struct crypto_alg *alg)
{
	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
		     "pcrypt(%s)", alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
		return -ENAMETOOLONG;

	memcpy(inst->alg.cra_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);

	inst->alg.cra_priority = alg->cra_priority + 100;
	inst->alg.cra_blocksize = alg->cra_blocksize;
	inst->alg.cra_alignmask = alg->cra_alignmask;

	return 0;
}

static int pcrypt_create_aead(struct crypto_template *tmpl, struct rtattr **tb,
			      u32 type, u32 mask)
{
	struct pcrypt_instance_ctx *ctx;
	struct crypto_attr_type *algt;
	struct aead_instance *inst;
	struct aead_alg *alg;
	const char *name;
	int err;

	algt = crypto_get_attr_type(tb);
	if (IS_ERR(algt))
		return PTR_ERR(algt);

	name = crypto_attr_alg_name(tb[1]);
	if (IS_ERR(name))
		return PTR_ERR(name);

	inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
	if (!inst)
		return -ENOMEM;

	ctx = aead_instance_ctx(inst);
	crypto_set_aead_spawn(&ctx->spawn, aead_crypto_instance(inst));

	err = crypto_grab_aead(&ctx->spawn, name,
			       algt->type & CRYPTO_ALG_AEAD_NEW,
			       algt->mask & CRYPTO_ALG_AEAD_NEW);
	if (err)
		goto out_free_inst;

	alg = crypto_spawn_aead_alg(&ctx->spawn);
	err = pcrypt_init_instance(aead_crypto_instance(inst), &alg->base);
	if (err)
		goto out_drop_aead;

	inst->alg.base.cra_flags = CRYPTO_ALG_ASYNC;
	inst->alg.base.cra_flags |= alg->base.cra_flags & CRYPTO_ALG_AEAD_NEW;

	inst->alg.ivsize = crypto_aead_alg_ivsize(alg);
	inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);

	inst->alg.base.cra_ctxsize = sizeof(struct pcrypt_aead_ctx);

	inst->alg.init = pcrypt_aead_init_tfm;
	inst->alg.exit = pcrypt_aead_exit_tfm;

	inst->alg.setkey = pcrypt_aead_setkey;
	inst->alg.setauthsize = pcrypt_aead_setauthsize;
	inst->alg.encrypt = pcrypt_aead_encrypt;
	inst->alg.decrypt = pcrypt_aead_decrypt;

	err = aead_register_instance(tmpl, inst);
	if (err)
		goto out_drop_aead;

out:
	return err;

out_drop_aead:
	crypto_drop_aead(&ctx->spawn);
out_free_inst:
	kfree(inst);
	goto out;
}

static int pcrypt_create(struct crypto_template *tmpl, struct rtattr **tb)
{
	struct crypto_attr_type *algt;

	algt = crypto_get_attr_type(tb);
	if (IS_ERR(algt))
		return PTR_ERR(algt);

	switch (algt->type & algt->mask & CRYPTO_ALG_TYPE_MASK) {
	case CRYPTO_ALG_TYPE_AEAD:
		return pcrypt_create_aead(tmpl, tb, algt->type, algt->mask);
	}

	return -EINVAL;
}

static void pcrypt_free(struct crypto_instance *inst)
{
	struct pcrypt_instance_ctx *ctx = crypto_instance_ctx(inst);

	crypto_drop_aead(&ctx->spawn);
	kfree(inst);
}

static int pcrypt_cpumask_change_notify(struct notifier_block *self,
					unsigned long val, void *data)
{
	struct padata_pcrypt *pcrypt;
	struct pcrypt_cpumask *new_mask, *old_mask;
	struct padata_cpumask *cpumask = (struct padata_cpumask *)data;

	if (!(val & PADATA_CPU_SERIAL))
		return 0;

	pcrypt = container_of(self, struct padata_pcrypt, nblock);
	new_mask = kmalloc(sizeof(*new_mask), GFP_KERNEL);
	if (!new_mask)
		return -ENOMEM;
	if (!alloc_cpumask_var(&new_mask->mask, GFP_KERNEL)) {
		kfree(new_mask);
		return -ENOMEM;
	}

	old_mask = pcrypt->cb_cpumask;

	cpumask_copy(new_mask->mask, cpumask->cbcpu);
	rcu_assign_pointer(pcrypt->cb_cpumask, new_mask);
	synchronize_rcu_bh();

	free_cpumask_var(old_mask->mask);
	kfree(old_mask);
	return 0;
}

static int pcrypt_sysfs_add(struct padata_instance *pinst, const char *name)
{
	int ret;

	pinst->kobj.kset = pcrypt_kset;
	ret = kobject_add(&pinst->kobj, NULL, name);
	if (!ret)
		kobject_uevent(&pinst->kobj, KOBJ_ADD);

	return ret;
}

static int pcrypt_init_padata(struct padata_pcrypt *pcrypt,
			      const char *name)
{
	int ret = -ENOMEM;
	struct pcrypt_cpumask *mask;

	get_online_cpus();

	pcrypt->wq = alloc_workqueue("%s", WQ_MEM_RECLAIM | WQ_CPU_INTENSIVE,
				     1, name);
	if (!pcrypt->wq)
		goto err;

	pcrypt->pinst = padata_alloc_possible(pcrypt->wq);
	if (!pcrypt->pinst)
		goto err_destroy_workqueue;

	mask = kmalloc(sizeof(*mask), GFP_KERNEL);
	if (!mask)
		goto err_free_padata;
	if (!alloc_cpumask_var(&mask->mask, GFP_KERNEL)) {
		kfree(mask);
		goto err_free_padata;
	}

	cpumask_and(mask->mask, cpu_possible_mask, cpu_online_mask);
	rcu_assign_pointer(pcrypt->cb_cpumask, mask);

	pcrypt->nblock.notifier_call = pcrypt_cpumask_change_notify;
	ret = padata_register_cpumask_notifier(pcrypt->pinst, &pcrypt->nblock);
	if (ret)
		goto err_free_cpumask;

	ret = pcrypt_sysfs_add(pcrypt->pinst, name);
	if (ret)
		goto err_unregister_notifier;

	put_online_cpus();

	return ret;

err_unregister_notifier:
	padata_unregister_cpumask_notifier(pcrypt->pinst, &pcrypt->nblock);
err_free_cpumask:
	free_cpumask_var(mask->mask);
	kfree(mask);
err_free_padata:
	padata_free(pcrypt->pinst);
err_destroy_workqueue:
	destroy_workqueue(pcrypt->wq);
err:
	put_online_cpus();

	return ret;
}

static void pcrypt_fini_padata(struct padata_pcrypt *pcrypt)
{
	free_cpumask_var(pcrypt->cb_cpumask->mask);
	kfree(pcrypt->cb_cpumask);

	padata_stop(pcrypt->pinst);
	padata_unregister_cpumask_notifier(pcrypt->pinst, &pcrypt->nblock);
	destroy_workqueue(pcrypt->wq);
	padata_free(pcrypt->pinst);
}

static struct crypto_template pcrypt_tmpl = {
	.name = "pcrypt",
	.create = pcrypt_create,
	.free = pcrypt_free,
	.module = THIS_MODULE,
};

static int __init pcrypt_init(void)
{
	int err = -ENOMEM;

	pcrypt_kset = kset_create_and_add("pcrypt", NULL, kernel_kobj);
	if (!pcrypt_kset)
		goto err;

	err = pcrypt_init_padata(&pencrypt, "pencrypt");
	if (err)
		goto err_unreg_kset;

	err = pcrypt_init_padata(&pdecrypt, "pdecrypt");
	if (err)
		goto err_deinit_pencrypt;

	padata_start(pencrypt.pinst);
	padata_start(pdecrypt.pinst);

	return crypto_register_template(&pcrypt_tmpl);

err_deinit_pencrypt:
	pcrypt_fini_padata(&pencrypt);
err_unreg_kset:
	kset_unregister(pcrypt_kset);
err:
	return err;
}

static void __exit pcrypt_exit(void)
{
	pcrypt_fini_padata(&pencrypt);
	pcrypt_fini_padata(&pdecrypt);

	kset_unregister(pcrypt_kset);
	crypto_unregister_template(&pcrypt_tmpl);
}

module_init(pcrypt_init);
module_exit(pcrypt_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
MODULE_DESCRIPTION("Parallel crypto wrapper");
MODULE_ALIAS_CRYPTO("pcrypt");