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1/*
2 * Cryptographic API for algorithms (i.e., low-level API).
3 *
4 * Copyright (c) 2006 Herbert Xu <[email protected]>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the Free
8 * Software Foundation; either version 2 of the License, or (at your option)
9 * any later version.
10 *
11 */
12
13#include <linux/err.h>
14#include <linux/errno.h>
15#include <linux/init.h>
16#include <linux/kernel.h>
17#include <linux/list.h>
18#include <linux/module.h>
19#include <linux/rtnetlink.h>
20#include <linux/string.h>
21
22#include "internal.h"
23
24static LIST_HEAD(crypto_template_list);
25
26void crypto_larval_error(const char *name, u32 type, u32 mask)
27{
28 struct crypto_alg *alg;
29
30 down_read(&crypto_alg_sem);
31 alg = __crypto_alg_lookup(name, type, mask);
32 up_read(&crypto_alg_sem);
33
34 if (alg) {
35 if (crypto_is_larval(alg)) {
36 struct crypto_larval *larval = (void *)alg;
37 complete_all(&larval->completion);
38 }
39 crypto_mod_put(alg);
40 }
41}
42EXPORT_SYMBOL_GPL(crypto_larval_error);
43
44static inline int crypto_set_driver_name(struct crypto_alg *alg)
45{
46 static const char suffix[] = "-generic";
47 char *driver_name = alg->cra_driver_name;
48 int len;
49
50 if (*driver_name)
51 return 0;
52
53 len = strlcpy(driver_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
54 if (len + sizeof(suffix) > CRYPTO_MAX_ALG_NAME)
55 return -ENAMETOOLONG;
56
57 memcpy(driver_name + len, suffix, sizeof(suffix));
58 return 0;
59}
60
61static int crypto_check_alg(struct crypto_alg *alg)
62{
63 if (alg->cra_alignmask & (alg->cra_alignmask + 1))
64 return -EINVAL;
65
66 if (alg->cra_blocksize > PAGE_SIZE / 8)
67 return -EINVAL;
68
69 if (alg->cra_priority < 0)
70 return -EINVAL;
71
72 return crypto_set_driver_name(alg);
73}
74
75static void crypto_destroy_instance(struct crypto_alg *alg)
76{
77 struct crypto_instance *inst = (void *)alg;
78 struct crypto_template *tmpl = inst->tmpl;
79
80 tmpl->free(inst);
81 crypto_tmpl_put(tmpl);
82}
83
84static void crypto_remove_spawn(struct crypto_spawn *spawn,
85 struct list_head *list,
86 struct list_head *secondary_spawns)
87{
88 struct crypto_instance *inst = spawn->inst;
89 struct crypto_template *tmpl = inst->tmpl;
90
91 list_del_init(&spawn->list);
92 spawn->alg = NULL;
93
94 if (crypto_is_dead(&inst->alg))
95 return;
96
97 inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
98 if (hlist_unhashed(&inst->list))
99 return;
100
101 if (!tmpl || !crypto_tmpl_get(tmpl))
102 return;
103
104 crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, &inst->alg);
105 list_move(&inst->alg.cra_list, list);
106 hlist_del(&inst->list);
107 inst->alg.cra_destroy = crypto_destroy_instance;
108
109 list_splice(&inst->alg.cra_users, secondary_spawns);
110}
111
112static void crypto_remove_spawns(struct list_head *spawns,
113 struct list_head *list, u32 new_type)
114{
115 struct crypto_spawn *spawn, *n;
116 LIST_HEAD(secondary_spawns);
117
118 list_for_each_entry_safe(spawn, n, spawns, list) {
119 if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
120 continue;
121
122 crypto_remove_spawn(spawn, list, &secondary_spawns);
123 }
124
125 while (!list_empty(&secondary_spawns)) {
126 list_for_each_entry_safe(spawn, n, &secondary_spawns, list)
127 crypto_remove_spawn(spawn, list, &secondary_spawns);
128 }
129}
130
131static int __crypto_register_alg(struct crypto_alg *alg,
132 struct list_head *list)
133{
134 struct crypto_alg *q;
135 int ret = -EAGAIN;
136
137 if (crypto_is_dead(alg))
138 goto out;
139
140 INIT_LIST_HEAD(&alg->cra_users);
141
142 ret = -EEXIST;
143
144 atomic_set(&alg->cra_refcnt, 1);
145 list_for_each_entry(q, &crypto_alg_list, cra_list) {
146 if (q == alg)
147 goto out;
148
149 if (crypto_is_moribund(q))
150 continue;
151
152 if (crypto_is_larval(q)) {
153 struct crypto_larval *larval = (void *)q;
154
155 /*
156 * Check to see if either our generic name or
157 * specific name can satisfy the name requested
158 * by the larval entry q.
159 */
160 if (strcmp(alg->cra_name, q->cra_name) &&
161 strcmp(alg->cra_driver_name, q->cra_name))
162 continue;
163
164 if (larval->adult)
165 continue;
166 if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
167 continue;
168 if (!crypto_mod_get(alg))
169 continue;
170
171 larval->adult = alg;
172 complete_all(&larval->completion);
173 continue;
174 }
175
176 if (strcmp(alg->cra_name, q->cra_name))
177 continue;
178
179 if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
180 q->cra_priority > alg->cra_priority)
181 continue;
182
183 crypto_remove_spawns(&q->cra_users, list, alg->cra_flags);
184 }
185
186 list_add(&alg->cra_list, &crypto_alg_list);
187
188 crypto_notify(CRYPTO_MSG_ALG_REGISTER, alg);
189 ret = 0;
190
191out:
192 return ret;
193}
194
195static void crypto_remove_final(struct list_head *list)
196{
197 struct crypto_alg *alg;
198 struct crypto_alg *n;
199
200 list_for_each_entry_safe(alg, n, list, cra_list) {
201 list_del_init(&alg->cra_list);
202 crypto_alg_put(alg);
203 }
204}
205
206int crypto_register_alg(struct crypto_alg *alg)
207{
208 LIST_HEAD(list);
209 int err;
210
211 err = crypto_check_alg(alg);
212 if (err)
213 return err;
214
215 down_write(&crypto_alg_sem);
216 err = __crypto_register_alg(alg, &list);
217 up_write(&crypto_alg_sem);
218
219 crypto_remove_final(&list);
220 return err;
221}
222EXPORT_SYMBOL_GPL(crypto_register_alg);
223
224static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
225{
226 if (unlikely(list_empty(&alg->cra_list)))
227 return -ENOENT;
228
229 alg->cra_flags |= CRYPTO_ALG_DEAD;
230
231 crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, alg);
232 list_del_init(&alg->cra_list);
233 crypto_remove_spawns(&alg->cra_users, list, alg->cra_flags);
234
235 return 0;
236}
237
238int crypto_unregister_alg(struct crypto_alg *alg)
239{
240 int ret;
241 LIST_HEAD(list);
242
243 down_write(&crypto_alg_sem);
244 ret = crypto_remove_alg(alg, &list);
245 up_write(&crypto_alg_sem);
246
247 if (ret)
248 return ret;
249
250 BUG_ON(atomic_read(&alg->cra_refcnt) != 1);
251 if (alg->cra_destroy)
252 alg->cra_destroy(alg);
253
254 crypto_remove_final(&list);
255 return 0;
256}
257EXPORT_SYMBOL_GPL(crypto_unregister_alg);
258
259int crypto_register_template(struct crypto_template *tmpl)
260{
261 struct crypto_template *q;
262 int err = -EEXIST;
263
264 down_write(&crypto_alg_sem);
265
266 list_for_each_entry(q, &crypto_template_list, list) {
267 if (q == tmpl)
268 goto out;
269 }
270
271 list_add(&tmpl->list, &crypto_template_list);
272 crypto_notify(CRYPTO_MSG_TMPL_REGISTER, tmpl);
273 err = 0;
274out:
275 up_write(&crypto_alg_sem);
276 return err;
277}
278EXPORT_SYMBOL_GPL(crypto_register_template);
279
280void crypto_unregister_template(struct crypto_template *tmpl)
281{
282 struct crypto_instance *inst;
283 struct hlist_node *p, *n;
284 struct hlist_head *list;
285 LIST_HEAD(users);
286
287 down_write(&crypto_alg_sem);
288
289 BUG_ON(list_empty(&tmpl->list));
290 list_del_init(&tmpl->list);
291
292 list = &tmpl->instances;
293 hlist_for_each_entry(inst, p, list, list) {
294 int err = crypto_remove_alg(&inst->alg, &users);
295 BUG_ON(err);
296 }
297
298 crypto_notify(CRYPTO_MSG_TMPL_UNREGISTER, tmpl);
299
300 up_write(&crypto_alg_sem);
301
302 hlist_for_each_entry_safe(inst, p, n, list, list) {
303 BUG_ON(atomic_read(&inst->alg.cra_refcnt) != 1);
304 tmpl->free(inst);
305 }
306 crypto_remove_final(&users);
307}
308EXPORT_SYMBOL_GPL(crypto_unregister_template);
309
310static struct crypto_template *__crypto_lookup_template(const char *name)
311{
312 struct crypto_template *q, *tmpl = NULL;
313
314 down_read(&crypto_alg_sem);
315 list_for_each_entry(q, &crypto_template_list, list) {
316 if (strcmp(q->name, name))
317 continue;
318 if (unlikely(!crypto_tmpl_get(q)))
319 continue;
320
321 tmpl = q;
322 break;
323 }
324 up_read(&crypto_alg_sem);
325
326 return tmpl;
327}
328
329struct crypto_template *crypto_lookup_template(const char *name)
330{
331 return try_then_request_module(__crypto_lookup_template(name), name);
332}
333EXPORT_SYMBOL_GPL(crypto_lookup_template);
334
335int crypto_register_instance(struct crypto_template *tmpl,
336 struct crypto_instance *inst)
337{
338 LIST_HEAD(list);
339 int err = -EINVAL;
340
341 err = crypto_check_alg(&inst->alg);
342 if (err)
343 goto err;
344
345 inst->alg.cra_module = tmpl->module;
346
347 down_write(&crypto_alg_sem);
348
349 err = __crypto_register_alg(&inst->alg, &list);
350 if (err)
351 goto unlock;
352
353 hlist_add_head(&inst->list, &tmpl->instances);
354 inst->tmpl = tmpl;
355
356unlock:
357 up_write(&crypto_alg_sem);
358
359 crypto_remove_final(&list);
360
361err:
362 return err;
363}
364EXPORT_SYMBOL_GPL(crypto_register_instance);
365
366int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg,
367 struct crypto_instance *inst, u32 mask)
368{
369 int err = -EAGAIN;
370
371 spawn->inst = inst;
372 spawn->mask = mask;
373
374 down_write(&crypto_alg_sem);
375 if (!crypto_is_moribund(alg)) {
376 list_add(&spawn->list, &alg->cra_users);
377 spawn->alg = alg;
378 err = 0;
379 }
380 up_write(&crypto_alg_sem);
381
382 return err;
383}
384EXPORT_SYMBOL_GPL(crypto_init_spawn);
385
386void crypto_drop_spawn(struct crypto_spawn *spawn)
387{
388 down_write(&crypto_alg_sem);
389 list_del(&spawn->list);
390 up_write(&crypto_alg_sem);
391}
392EXPORT_SYMBOL_GPL(crypto_drop_spawn);
393
394struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
395 u32 mask)
396{
397 struct crypto_alg *alg;
398 struct crypto_alg *alg2;
399 struct crypto_tfm *tfm;
400
401 down_read(&crypto_alg_sem);
402 alg = spawn->alg;
403 alg2 = alg;
404 if (alg2)
405 alg2 = crypto_mod_get(alg2);
406 up_read(&crypto_alg_sem);
407
408 if (!alg2) {
409 if (alg)
410 crypto_shoot_alg(alg);
411 return ERR_PTR(-EAGAIN);
412 }
413
414 tfm = ERR_PTR(-EINVAL);
415 if (unlikely((alg->cra_flags ^ type) & mask))
416 goto out_put_alg;
417
418 tfm = __crypto_alloc_tfm(alg, type, mask);
419 if (IS_ERR(tfm))
420 goto out_put_alg;
421
422 return tfm;
423
424out_put_alg:
425 crypto_mod_put(alg);
426 return tfm;
427}
428EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
429
430int crypto_register_notifier(struct notifier_block *nb)
431{
432 return blocking_notifier_chain_register(&crypto_chain, nb);
433}
434EXPORT_SYMBOL_GPL(crypto_register_notifier);
435
436int crypto_unregister_notifier(struct notifier_block *nb)
437{
438 return blocking_notifier_chain_unregister(&crypto_chain, nb);
439}
440EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
441
442struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
443{
444 struct rtattr *rta = tb[0];
445 struct crypto_attr_type *algt;
446
447 if (!rta)
448 return ERR_PTR(-ENOENT);
449 if (RTA_PAYLOAD(rta) < sizeof(*algt))
450 return ERR_PTR(-EINVAL);
451 if (rta->rta_type != CRYPTOA_TYPE)
452 return ERR_PTR(-EINVAL);
453
454 algt = RTA_DATA(rta);
455
456 return algt;
457}
458EXPORT_SYMBOL_GPL(crypto_get_attr_type);
459
460int crypto_check_attr_type(struct rtattr **tb, u32 type)
461{
462 struct crypto_attr_type *algt;
463
464 algt = crypto_get_attr_type(tb);
465 if (IS_ERR(algt))
466 return PTR_ERR(algt);
467
468 if ((algt->type ^ type) & algt->mask)
469 return -EINVAL;
470
471 return 0;
472}
473EXPORT_SYMBOL_GPL(crypto_check_attr_type);
474
475const char *crypto_attr_alg_name(struct rtattr *rta)
476{
477 struct crypto_attr_alg *alga;
478
479 if (!rta)
480 return ERR_PTR(-ENOENT);
481 if (RTA_PAYLOAD(rta) < sizeof(*alga))
482 return ERR_PTR(-EINVAL);
483 if (rta->rta_type != CRYPTOA_ALG)
484 return ERR_PTR(-EINVAL);
485
486 alga = RTA_DATA(rta);
487 alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
488
489 return alga->name;
490}
491EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
492
493struct crypto_alg *crypto_attr_alg(struct rtattr *rta, u32 type, u32 mask)
494{
495 const char *name;
496 int err;
497
498 name = crypto_attr_alg_name(rta);
499 err = PTR_ERR(name);
500 if (IS_ERR(name))
501 return ERR_PTR(err);
502
503 return crypto_alg_mod_lookup(name, type, mask);
504}
505EXPORT_SYMBOL_GPL(crypto_attr_alg);
506
507int crypto_attr_u32(struct rtattr *rta, u32 *num)
508{
509 struct crypto_attr_u32 *nu32;
510
511 if (!rta)
512 return -ENOENT;
513 if (RTA_PAYLOAD(rta) < sizeof(*nu32))
514 return -EINVAL;
515 if (rta->rta_type != CRYPTOA_U32)
516 return -EINVAL;
517
518 nu32 = RTA_DATA(rta);
519 *num = nu32->num;
520
521 return 0;
522}
523EXPORT_SYMBOL_GPL(crypto_attr_u32);
524
525struct crypto_instance *crypto_alloc_instance(const char *name,
526 struct crypto_alg *alg)
527{
528 struct crypto_instance *inst;
529 struct crypto_spawn *spawn;
530 int err;
531
532 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
533 if (!inst)
534 return ERR_PTR(-ENOMEM);
535
536 err = -ENAMETOOLONG;
537 if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
538 alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
539 goto err_free_inst;
540
541 if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
542 name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
543 goto err_free_inst;
544
545 spawn = crypto_instance_ctx(inst);
546 err = crypto_init_spawn(spawn, alg, inst,
547 CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
548
549 if (err)
550 goto err_free_inst;
551
552 return inst;
553
554err_free_inst:
555 kfree(inst);
556 return ERR_PTR(err);
557}
558EXPORT_SYMBOL_GPL(crypto_alloc_instance);
559
560void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
561{
562 INIT_LIST_HEAD(&queue->list);
563 queue->backlog = &queue->list;
564 queue->qlen = 0;
565 queue->max_qlen = max_qlen;
566}
567EXPORT_SYMBOL_GPL(crypto_init_queue);
568
569int crypto_enqueue_request(struct crypto_queue *queue,
570 struct crypto_async_request *request)
571{
572 int err = -EINPROGRESS;
573
574 if (unlikely(queue->qlen >= queue->max_qlen)) {
575 err = -EBUSY;
576 if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG))
577 goto out;
578 if (queue->backlog == &queue->list)
579 queue->backlog = &request->list;
580 }
581
582 queue->qlen++;
583 list_add_tail(&request->list, &queue->list);
584
585out:
586 return err;
587}
588EXPORT_SYMBOL_GPL(crypto_enqueue_request);
589
590struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
591{
592 struct list_head *request;
593
594 if (unlikely(!queue->qlen))
595 return NULL;
596
597 queue->qlen--;
598
599 if (queue->backlog != &queue->list)
600 queue->backlog = queue->backlog->next;
601
602 request = queue->list.next;
603 list_del(request);
604
605 return list_entry(request, struct crypto_async_request, list);
606}
607EXPORT_SYMBOL_GPL(crypto_dequeue_request);
608
609int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm)
610{
611 struct crypto_async_request *req;
612
613 list_for_each_entry(req, &queue->list, list) {
614 if (req->tfm == tfm)
615 return 1;
616 }
617
618 return 0;
619}
620EXPORT_SYMBOL_GPL(crypto_tfm_in_queue);
621
622static inline void crypto_inc_byte(u8 *a, unsigned int size)
623{
624 u8 *b = (a + size);
625 u8 c;
626
627 for (; size; size--) {
628 c = *--b + 1;
629 *b = c;
630 if (c)
631 break;
632 }
633}
634
635void crypto_inc(u8 *a, unsigned int size)
636{
637 __be32 *b = (__be32 *)(a + size);
638 u32 c;
639
640 for (; size >= 4; size -= 4) {
641 c = be32_to_cpu(*--b) + 1;
642 *b = cpu_to_be32(c);
643 if (c)
644 return;
645 }
646
647 crypto_inc_byte(a, size);
648}
649EXPORT_SYMBOL_GPL(crypto_inc);
650
651static inline void crypto_xor_byte(u8 *a, const u8 *b, unsigned int size)
652{
653 for (; size; size--)
654 *a++ ^= *b++;
655}
656
657void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
658{
659 u32 *a = (u32 *)dst;
660 u32 *b = (u32 *)src;
661
662 for (; size >= 4; size -= 4)
663 *a++ ^= *b++;
664
665 crypto_xor_byte((u8 *)a, (u8 *)b, size);
666}
667EXPORT_SYMBOL_GPL(crypto_xor);
668
669static int __init crypto_algapi_init(void)
670{
671 crypto_init_proc();
672 return 0;
673}
674
675static void __exit crypto_algapi_exit(void)
676{
677 crypto_exit_proc();
678}
679
680module_init(crypto_algapi_init);
681module_exit(crypto_algapi_exit);
682
683MODULE_LICENSE("GPL");
684MODULE_DESCRIPTION("Cryptographic algorithms API");