usb: gadget: composite: Fix cdev null after rmmod
[linux-3.10.git] / crypto / algapi.c
1 /*
2  * Cryptographic API for algorithms (i.e., low-level API).
3  *
4  * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
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/slab.h>
21 #include <linux/string.h>
22
23 #include "internal.h"
24
25 static LIST_HEAD(crypto_template_list);
26
27 static inline int crypto_set_driver_name(struct crypto_alg *alg)
28 {
29         static const char suffix[] = "-generic";
30         char *driver_name = alg->cra_driver_name;
31         int len;
32
33         if (*driver_name)
34                 return 0;
35
36         len = strlcpy(driver_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
37         if (len + sizeof(suffix) > CRYPTO_MAX_ALG_NAME)
38                 return -ENAMETOOLONG;
39
40         memcpy(driver_name + len, suffix, sizeof(suffix));
41         return 0;
42 }
43
44 static int crypto_check_alg(struct crypto_alg *alg)
45 {
46         if (alg->cra_alignmask & (alg->cra_alignmask + 1))
47                 return -EINVAL;
48
49         if (alg->cra_blocksize > PAGE_SIZE / 8)
50                 return -EINVAL;
51
52         if (alg->cra_priority < 0)
53                 return -EINVAL;
54
55         return crypto_set_driver_name(alg);
56 }
57
58 static void crypto_destroy_instance(struct crypto_alg *alg)
59 {
60         struct crypto_instance *inst = (void *)alg;
61         struct crypto_template *tmpl = inst->tmpl;
62
63         tmpl->free(inst);
64         crypto_tmpl_put(tmpl);
65 }
66
67 static struct list_head *crypto_more_spawns(struct crypto_alg *alg,
68                                             struct list_head *stack,
69                                             struct list_head *top,
70                                             struct list_head *secondary_spawns)
71 {
72         struct crypto_spawn *spawn, *n;
73
74         if (list_empty(stack))
75                 return NULL;
76
77         spawn = list_first_entry(stack, struct crypto_spawn, list);
78         n = list_entry(spawn->list.next, struct crypto_spawn, list);
79
80         if (spawn->alg && &n->list != stack && !n->alg)
81                 n->alg = (n->list.next == stack) ? alg :
82                          &list_entry(n->list.next, struct crypto_spawn,
83                                      list)->inst->alg;
84
85         list_move(&spawn->list, secondary_spawns);
86
87         return &n->list == stack ? top : &n->inst->alg.cra_users;
88 }
89
90 static void crypto_remove_spawn(struct crypto_spawn *spawn,
91                                 struct list_head *list)
92 {
93         struct crypto_instance *inst = spawn->inst;
94         struct crypto_template *tmpl = inst->tmpl;
95
96         if (crypto_is_dead(&inst->alg))
97                 return;
98
99         inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
100         if (hlist_unhashed(&inst->list))
101                 return;
102
103         if (!tmpl || !crypto_tmpl_get(tmpl))
104                 return;
105
106         crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, &inst->alg);
107         list_move(&inst->alg.cra_list, list);
108         hlist_del(&inst->list);
109         inst->alg.cra_destroy = crypto_destroy_instance;
110
111         BUG_ON(!list_empty(&inst->alg.cra_users));
112 }
113
114 void crypto_remove_spawns(struct crypto_alg *alg, struct list_head *list,
115                           struct crypto_alg *nalg)
116 {
117         u32 new_type = (nalg ?: alg)->cra_flags;
118         struct crypto_spawn *spawn, *n;
119         LIST_HEAD(secondary_spawns);
120         struct list_head *spawns;
121         LIST_HEAD(stack);
122         LIST_HEAD(top);
123
124         spawns = &alg->cra_users;
125         list_for_each_entry_safe(spawn, n, spawns, list) {
126                 if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
127                         continue;
128
129                 list_move(&spawn->list, &top);
130         }
131
132         spawns = &top;
133         do {
134                 while (!list_empty(spawns)) {
135                         struct crypto_instance *inst;
136
137                         spawn = list_first_entry(spawns, struct crypto_spawn,
138                                                  list);
139                         inst = spawn->inst;
140
141                         BUG_ON(&inst->alg == alg);
142
143                         list_move(&spawn->list, &stack);
144
145                         if (&inst->alg == nalg)
146                                 break;
147
148                         spawn->alg = NULL;
149                         spawns = &inst->alg.cra_users;
150                 }
151         } while ((spawns = crypto_more_spawns(alg, &stack, &top,
152                                               &secondary_spawns)));
153
154         list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {
155                 if (spawn->alg)
156                         list_move(&spawn->list, &spawn->alg->cra_users);
157                 else
158                         crypto_remove_spawn(spawn, list);
159         }
160 }
161 EXPORT_SYMBOL_GPL(crypto_remove_spawns);
162
163 static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg)
164 {
165         struct crypto_alg *q;
166         struct crypto_larval *larval;
167         int ret = -EAGAIN;
168
169         if (crypto_is_dead(alg))
170                 goto err;
171
172         INIT_LIST_HEAD(&alg->cra_users);
173
174         /* No cheating! */
175         alg->cra_flags &= ~CRYPTO_ALG_TESTED;
176
177         ret = -EEXIST;
178
179         atomic_set(&alg->cra_refcnt, 1);
180         list_for_each_entry(q, &crypto_alg_list, cra_list) {
181                 if (q == alg)
182                         goto err;
183
184                 if (crypto_is_moribund(q))
185                         continue;
186
187                 if (crypto_is_larval(q)) {
188                         if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
189                                 goto err;
190                         continue;
191                 }
192
193                 if (!strcmp(q->cra_driver_name, alg->cra_name) ||
194                     !strcmp(q->cra_name, alg->cra_driver_name))
195                         goto err;
196         }
197
198         larval = crypto_larval_alloc(alg->cra_name,
199                                      alg->cra_flags | CRYPTO_ALG_TESTED, 0);
200         if (IS_ERR(larval))
201                 goto out;
202
203         ret = -ENOENT;
204         larval->adult = crypto_mod_get(alg);
205         if (!larval->adult)
206                 goto free_larval;
207
208         atomic_set(&larval->alg.cra_refcnt, 1);
209         memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
210                CRYPTO_MAX_ALG_NAME);
211         larval->alg.cra_priority = alg->cra_priority;
212
213         list_add(&alg->cra_list, &crypto_alg_list);
214         list_add(&larval->alg.cra_list, &crypto_alg_list);
215
216 out:
217         return larval;
218
219 free_larval:
220         kfree(larval);
221 err:
222         larval = ERR_PTR(ret);
223         goto out;
224 }
225
226 void crypto_alg_tested(const char *name, int err)
227 {
228         struct crypto_larval *test;
229         struct crypto_alg *alg;
230         struct crypto_alg *q;
231         LIST_HEAD(list);
232
233         down_write(&crypto_alg_sem);
234         list_for_each_entry(q, &crypto_alg_list, cra_list) {
235                 if (crypto_is_moribund(q) || !crypto_is_larval(q))
236                         continue;
237
238                 test = (struct crypto_larval *)q;
239
240                 if (!strcmp(q->cra_driver_name, name))
241                         goto found;
242         }
243
244         printk(KERN_ERR "alg: Unexpected test result for %s: %d\n", name, err);
245         goto unlock;
246
247 found:
248         q->cra_flags |= CRYPTO_ALG_DEAD;
249         alg = test->adult;
250         if (err || list_empty(&alg->cra_list))
251                 goto complete;
252
253         alg->cra_flags |= CRYPTO_ALG_TESTED;
254
255         list_for_each_entry(q, &crypto_alg_list, cra_list) {
256                 if (q == alg)
257                         continue;
258
259                 if (crypto_is_moribund(q))
260                         continue;
261
262                 if (crypto_is_larval(q)) {
263                         struct crypto_larval *larval = (void *)q;
264
265                         /*
266                          * Check to see if either our generic name or
267                          * specific name can satisfy the name requested
268                          * by the larval entry q.
269                          */
270                         if (strcmp(alg->cra_name, q->cra_name) &&
271                             strcmp(alg->cra_driver_name, q->cra_name))
272                                 continue;
273
274                         if (larval->adult)
275                                 continue;
276                         if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
277                                 continue;
278                         if (!crypto_mod_get(alg))
279                                 continue;
280
281                         larval->adult = alg;
282                         continue;
283                 }
284
285                 if (strcmp(alg->cra_name, q->cra_name))
286                         continue;
287
288                 if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
289                     q->cra_priority > alg->cra_priority)
290                         continue;
291
292                 crypto_remove_spawns(q, &list, alg);
293         }
294
295 complete:
296         complete_all(&test->completion);
297
298 unlock:
299         up_write(&crypto_alg_sem);
300
301         crypto_remove_final(&list);
302 }
303 EXPORT_SYMBOL_GPL(crypto_alg_tested);
304
305 void crypto_remove_final(struct list_head *list)
306 {
307         struct crypto_alg *alg;
308         struct crypto_alg *n;
309
310         list_for_each_entry_safe(alg, n, list, cra_list) {
311                 list_del_init(&alg->cra_list);
312                 crypto_alg_put(alg);
313         }
314 }
315 EXPORT_SYMBOL_GPL(crypto_remove_final);
316
317 static void crypto_wait_for_test(struct crypto_larval *larval)
318 {
319         int err;
320
321         err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult);
322         if (err != NOTIFY_STOP) {
323                 if (WARN_ON(err != NOTIFY_DONE))
324                         goto out;
325                 crypto_alg_tested(larval->alg.cra_driver_name, 0);
326         }
327
328         err = wait_for_completion_interruptible(&larval->completion);
329         WARN_ON(err);
330
331 out:
332         crypto_larval_kill(&larval->alg);
333 }
334
335 int crypto_register_alg(struct crypto_alg *alg)
336 {
337         struct crypto_larval *larval;
338         int err;
339
340         err = crypto_check_alg(alg);
341         if (err)
342                 return err;
343
344         down_write(&crypto_alg_sem);
345         larval = __crypto_register_alg(alg);
346         up_write(&crypto_alg_sem);
347
348         if (IS_ERR(larval))
349                 return PTR_ERR(larval);
350
351         crypto_wait_for_test(larval);
352         return 0;
353 }
354 EXPORT_SYMBOL_GPL(crypto_register_alg);
355
356 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
357 {
358         if (unlikely(list_empty(&alg->cra_list)))
359                 return -ENOENT;
360
361         alg->cra_flags |= CRYPTO_ALG_DEAD;
362
363         crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, alg);
364         list_del_init(&alg->cra_list);
365         crypto_remove_spawns(alg, list, NULL);
366
367         return 0;
368 }
369
370 int crypto_unregister_alg(struct crypto_alg *alg)
371 {
372         int ret;
373         LIST_HEAD(list);
374
375         down_write(&crypto_alg_sem);
376         ret = crypto_remove_alg(alg, &list);
377         up_write(&crypto_alg_sem);
378
379         if (ret)
380                 return ret;
381
382         BUG_ON(atomic_read(&alg->cra_refcnt) != 1);
383         if (alg->cra_destroy)
384                 alg->cra_destroy(alg);
385
386         crypto_remove_final(&list);
387         return 0;
388 }
389 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
390
391 int crypto_register_algs(struct crypto_alg *algs, int count)
392 {
393         int i, ret;
394
395         for (i = 0; i < count; i++) {
396                 ret = crypto_register_alg(&algs[i]);
397                 if (ret)
398                         goto err;
399         }
400
401         return 0;
402
403 err:
404         for (--i; i >= 0; --i)
405                 crypto_unregister_alg(&algs[i]);
406
407         return ret;
408 }
409 EXPORT_SYMBOL_GPL(crypto_register_algs);
410
411 int crypto_unregister_algs(struct crypto_alg *algs, int count)
412 {
413         int i, ret;
414
415         for (i = 0; i < count; i++) {
416                 ret = crypto_unregister_alg(&algs[i]);
417                 if (ret)
418                         pr_err("Failed to unregister %s %s: %d\n",
419                                algs[i].cra_driver_name, algs[i].cra_name, ret);
420         }
421
422         return 0;
423 }
424 EXPORT_SYMBOL_GPL(crypto_unregister_algs);
425
426 int crypto_register_template(struct crypto_template *tmpl)
427 {
428         struct crypto_template *q;
429         int err = -EEXIST;
430
431         down_write(&crypto_alg_sem);
432
433         list_for_each_entry(q, &crypto_template_list, list) {
434                 if (q == tmpl)
435                         goto out;
436         }
437
438         list_add(&tmpl->list, &crypto_template_list);
439         crypto_notify(CRYPTO_MSG_TMPL_REGISTER, tmpl);
440         err = 0;
441 out:
442         up_write(&crypto_alg_sem);
443         return err;
444 }
445 EXPORT_SYMBOL_GPL(crypto_register_template);
446
447 void crypto_unregister_template(struct crypto_template *tmpl)
448 {
449         struct crypto_instance *inst;
450         struct hlist_node *n;
451         struct hlist_head *list;
452         LIST_HEAD(users);
453
454         down_write(&crypto_alg_sem);
455
456         BUG_ON(list_empty(&tmpl->list));
457         list_del_init(&tmpl->list);
458
459         list = &tmpl->instances;
460         hlist_for_each_entry(inst, list, list) {
461                 int err = crypto_remove_alg(&inst->alg, &users);
462                 BUG_ON(err);
463         }
464
465         crypto_notify(CRYPTO_MSG_TMPL_UNREGISTER, tmpl);
466
467         up_write(&crypto_alg_sem);
468
469         hlist_for_each_entry_safe(inst, n, list, list) {
470                 BUG_ON(atomic_read(&inst->alg.cra_refcnt) != 1);
471                 tmpl->free(inst);
472         }
473         crypto_remove_final(&users);
474 }
475 EXPORT_SYMBOL_GPL(crypto_unregister_template);
476
477 static struct crypto_template *__crypto_lookup_template(const char *name)
478 {
479         struct crypto_template *q, *tmpl = NULL;
480
481         down_read(&crypto_alg_sem);
482         list_for_each_entry(q, &crypto_template_list, list) {
483                 if (strcmp(q->name, name))
484                         continue;
485                 if (unlikely(!crypto_tmpl_get(q)))
486                         continue;
487
488                 tmpl = q;
489                 break;
490         }
491         up_read(&crypto_alg_sem);
492
493         return tmpl;
494 }
495
496 struct crypto_template *crypto_lookup_template(const char *name)
497 {
498         return try_then_request_module(__crypto_lookup_template(name), "%s",
499                                        name);
500 }
501 EXPORT_SYMBOL_GPL(crypto_lookup_template);
502
503 int crypto_register_instance(struct crypto_template *tmpl,
504                              struct crypto_instance *inst)
505 {
506         struct crypto_larval *larval;
507         int err;
508
509         err = crypto_check_alg(&inst->alg);
510         if (err)
511                 goto err;
512
513         inst->alg.cra_module = tmpl->module;
514         inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
515
516         down_write(&crypto_alg_sem);
517
518         larval = __crypto_register_alg(&inst->alg);
519         if (IS_ERR(larval))
520                 goto unlock;
521
522         hlist_add_head(&inst->list, &tmpl->instances);
523         inst->tmpl = tmpl;
524
525 unlock:
526         up_write(&crypto_alg_sem);
527
528         err = PTR_ERR(larval);
529         if (IS_ERR(larval))
530                 goto err;
531
532         crypto_wait_for_test(larval);
533         err = 0;
534
535 err:
536         return err;
537 }
538 EXPORT_SYMBOL_GPL(crypto_register_instance);
539
540 int crypto_unregister_instance(struct crypto_alg *alg)
541 {
542         int err;
543         struct crypto_instance *inst = (void *)alg;
544         struct crypto_template *tmpl = inst->tmpl;
545         LIST_HEAD(users);
546
547         if (!(alg->cra_flags & CRYPTO_ALG_INSTANCE))
548                 return -EINVAL;
549
550         BUG_ON(atomic_read(&alg->cra_refcnt) != 1);
551
552         down_write(&crypto_alg_sem);
553
554         hlist_del_init(&inst->list);
555         err = crypto_remove_alg(alg, &users);
556
557         up_write(&crypto_alg_sem);
558
559         if (err)
560                 return err;
561
562         tmpl->free(inst);
563         crypto_remove_final(&users);
564
565         return 0;
566 }
567 EXPORT_SYMBOL_GPL(crypto_unregister_instance);
568
569 int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg,
570                       struct crypto_instance *inst, u32 mask)
571 {
572         int err = -EAGAIN;
573
574         spawn->inst = inst;
575         spawn->mask = mask;
576
577         down_write(&crypto_alg_sem);
578         if (!crypto_is_moribund(alg)) {
579                 list_add(&spawn->list, &alg->cra_users);
580                 spawn->alg = alg;
581                 err = 0;
582         }
583         up_write(&crypto_alg_sem);
584
585         return err;
586 }
587 EXPORT_SYMBOL_GPL(crypto_init_spawn);
588
589 int crypto_init_spawn2(struct crypto_spawn *spawn, struct crypto_alg *alg,
590                        struct crypto_instance *inst,
591                        const struct crypto_type *frontend)
592 {
593         int err = -EINVAL;
594
595         if ((alg->cra_flags ^ frontend->type) & frontend->maskset)
596                 goto out;
597
598         spawn->frontend = frontend;
599         err = crypto_init_spawn(spawn, alg, inst, frontend->maskset);
600
601 out:
602         return err;
603 }
604 EXPORT_SYMBOL_GPL(crypto_init_spawn2);
605
606 void crypto_drop_spawn(struct crypto_spawn *spawn)
607 {
608         if (!spawn->alg)
609                 return;
610
611         down_write(&crypto_alg_sem);
612         list_del(&spawn->list);
613         up_write(&crypto_alg_sem);
614 }
615 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
616
617 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
618 {
619         struct crypto_alg *alg;
620         struct crypto_alg *alg2;
621
622         down_read(&crypto_alg_sem);
623         alg = spawn->alg;
624         alg2 = alg;
625         if (alg2)
626                 alg2 = crypto_mod_get(alg2);
627         up_read(&crypto_alg_sem);
628
629         if (!alg2) {
630                 if (alg)
631                         crypto_shoot_alg(alg);
632                 return ERR_PTR(-EAGAIN);
633         }
634
635         return alg;
636 }
637
638 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
639                                     u32 mask)
640 {
641         struct crypto_alg *alg;
642         struct crypto_tfm *tfm;
643
644         alg = crypto_spawn_alg(spawn);
645         if (IS_ERR(alg))
646                 return ERR_CAST(alg);
647
648         tfm = ERR_PTR(-EINVAL);
649         if (unlikely((alg->cra_flags ^ type) & mask))
650                 goto out_put_alg;
651
652         tfm = __crypto_alloc_tfm(alg, type, mask);
653         if (IS_ERR(tfm))
654                 goto out_put_alg;
655
656         return tfm;
657
658 out_put_alg:
659         crypto_mod_put(alg);
660         return tfm;
661 }
662 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
663
664 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
665 {
666         struct crypto_alg *alg;
667         struct crypto_tfm *tfm;
668
669         alg = crypto_spawn_alg(spawn);
670         if (IS_ERR(alg))
671                 return ERR_CAST(alg);
672
673         tfm = crypto_create_tfm(alg, spawn->frontend);
674         if (IS_ERR(tfm))
675                 goto out_put_alg;
676
677         return tfm;
678
679 out_put_alg:
680         crypto_mod_put(alg);
681         return tfm;
682 }
683 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
684
685 int crypto_register_notifier(struct notifier_block *nb)
686 {
687         return blocking_notifier_chain_register(&crypto_chain, nb);
688 }
689 EXPORT_SYMBOL_GPL(crypto_register_notifier);
690
691 int crypto_unregister_notifier(struct notifier_block *nb)
692 {
693         return blocking_notifier_chain_unregister(&crypto_chain, nb);
694 }
695 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
696
697 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
698 {
699         struct rtattr *rta = tb[0];
700         struct crypto_attr_type *algt;
701
702         if (!rta)
703                 return ERR_PTR(-ENOENT);
704         if (RTA_PAYLOAD(rta) < sizeof(*algt))
705                 return ERR_PTR(-EINVAL);
706         if (rta->rta_type != CRYPTOA_TYPE)
707                 return ERR_PTR(-EINVAL);
708
709         algt = RTA_DATA(rta);
710
711         return algt;
712 }
713 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
714
715 int crypto_check_attr_type(struct rtattr **tb, u32 type)
716 {
717         struct crypto_attr_type *algt;
718
719         algt = crypto_get_attr_type(tb);
720         if (IS_ERR(algt))
721                 return PTR_ERR(algt);
722
723         if ((algt->type ^ type) & algt->mask)
724                 return -EINVAL;
725
726         return 0;
727 }
728 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
729
730 const char *crypto_attr_alg_name(struct rtattr *rta)
731 {
732         struct crypto_attr_alg *alga;
733
734         if (!rta)
735                 return ERR_PTR(-ENOENT);
736         if (RTA_PAYLOAD(rta) < sizeof(*alga))
737                 return ERR_PTR(-EINVAL);
738         if (rta->rta_type != CRYPTOA_ALG)
739                 return ERR_PTR(-EINVAL);
740
741         alga = RTA_DATA(rta);
742         alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
743
744         return alga->name;
745 }
746 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
747
748 struct crypto_alg *crypto_attr_alg2(struct rtattr *rta,
749                                     const struct crypto_type *frontend,
750                                     u32 type, u32 mask)
751 {
752         const char *name;
753
754         name = crypto_attr_alg_name(rta);
755         if (IS_ERR(name))
756                 return ERR_CAST(name);
757
758         return crypto_find_alg(name, frontend, type, mask);
759 }
760 EXPORT_SYMBOL_GPL(crypto_attr_alg2);
761
762 int crypto_attr_u32(struct rtattr *rta, u32 *num)
763 {
764         struct crypto_attr_u32 *nu32;
765
766         if (!rta)
767                 return -ENOENT;
768         if (RTA_PAYLOAD(rta) < sizeof(*nu32))
769                 return -EINVAL;
770         if (rta->rta_type != CRYPTOA_U32)
771                 return -EINVAL;
772
773         nu32 = RTA_DATA(rta);
774         *num = nu32->num;
775
776         return 0;
777 }
778 EXPORT_SYMBOL_GPL(crypto_attr_u32);
779
780 void *crypto_alloc_instance2(const char *name, struct crypto_alg *alg,
781                              unsigned int head)
782 {
783         struct crypto_instance *inst;
784         char *p;
785         int err;
786
787         p = kzalloc(head + sizeof(*inst) + sizeof(struct crypto_spawn),
788                     GFP_KERNEL);
789         if (!p)
790                 return ERR_PTR(-ENOMEM);
791
792         inst = (void *)(p + head);
793
794         err = -ENAMETOOLONG;
795         if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
796                      alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
797                 goto err_free_inst;
798
799         if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
800                      name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
801                 goto err_free_inst;
802
803         return p;
804
805 err_free_inst:
806         kfree(p);
807         return ERR_PTR(err);
808 }
809 EXPORT_SYMBOL_GPL(crypto_alloc_instance2);
810
811 struct crypto_instance *crypto_alloc_instance(const char *name,
812                                               struct crypto_alg *alg)
813 {
814         struct crypto_instance *inst;
815         struct crypto_spawn *spawn;
816         int err;
817
818         inst = crypto_alloc_instance2(name, alg, 0);
819         if (IS_ERR(inst))
820                 goto out;
821
822         spawn = crypto_instance_ctx(inst);
823         err = crypto_init_spawn(spawn, alg, inst,
824                                 CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
825
826         if (err)
827                 goto err_free_inst;
828
829         return inst;
830
831 err_free_inst:
832         kfree(inst);
833         inst = ERR_PTR(err);
834
835 out:
836         return inst;
837 }
838 EXPORT_SYMBOL_GPL(crypto_alloc_instance);
839
840 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
841 {
842         INIT_LIST_HEAD(&queue->list);
843         queue->backlog = &queue->list;
844         queue->qlen = 0;
845         queue->max_qlen = max_qlen;
846 }
847 EXPORT_SYMBOL_GPL(crypto_init_queue);
848
849 int crypto_enqueue_request(struct crypto_queue *queue,
850                            struct crypto_async_request *request)
851 {
852         int err = -EINPROGRESS;
853
854         if (unlikely(queue->qlen >= queue->max_qlen)) {
855                 err = -EBUSY;
856                 if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG))
857                         goto out;
858                 if (queue->backlog == &queue->list)
859                         queue->backlog = &request->list;
860         }
861
862         queue->qlen++;
863         list_add_tail(&request->list, &queue->list);
864
865 out:
866         return err;
867 }
868 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
869
870 void *__crypto_dequeue_request(struct crypto_queue *queue, unsigned int offset)
871 {
872         struct list_head *request;
873
874         if (unlikely(!queue->qlen))
875                 return NULL;
876
877         queue->qlen--;
878
879         if (queue->backlog != &queue->list)
880                 queue->backlog = queue->backlog->next;
881
882         request = queue->list.next;
883         list_del(request);
884
885         return (char *)list_entry(request, struct crypto_async_request, list) -
886                offset;
887 }
888 EXPORT_SYMBOL_GPL(__crypto_dequeue_request);
889
890 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
891 {
892         return __crypto_dequeue_request(queue, 0);
893 }
894 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
895
896 int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm)
897 {
898         struct crypto_async_request *req;
899
900         list_for_each_entry(req, &queue->list, list) {
901                 if (req->tfm == tfm)
902                         return 1;
903         }
904
905         return 0;
906 }
907 EXPORT_SYMBOL_GPL(crypto_tfm_in_queue);
908
909 static inline void crypto_inc_byte(u8 *a, unsigned int size)
910 {
911         u8 *b = (a + size);
912         u8 c;
913
914         for (; size; size--) {
915                 c = *--b + 1;
916                 *b = c;
917                 if (c)
918                         break;
919         }
920 }
921
922 void crypto_inc(u8 *a, unsigned int size)
923 {
924         __be32 *b = (__be32 *)(a + size);
925         u32 c;
926
927         for (; size >= 4; size -= 4) {
928                 c = be32_to_cpu(*--b) + 1;
929                 *b = cpu_to_be32(c);
930                 if (c)
931                         return;
932         }
933
934         crypto_inc_byte(a, size);
935 }
936 EXPORT_SYMBOL_GPL(crypto_inc);
937
938 static inline void crypto_xor_byte(u8 *a, const u8 *b, unsigned int size)
939 {
940         for (; size; size--)
941                 *a++ ^= *b++;
942 }
943
944 void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
945 {
946         u32 *a = (u32 *)dst;
947         u32 *b = (u32 *)src;
948
949         for (; size >= 4; size -= 4)
950                 *a++ ^= *b++;
951
952         crypto_xor_byte((u8 *)a, (u8 *)b, size);
953 }
954 EXPORT_SYMBOL_GPL(crypto_xor);
955
956 static int __init crypto_algapi_init(void)
957 {
958         crypto_init_proc();
959         return 0;
960 }
961
962 static void __exit crypto_algapi_exit(void)
963 {
964         crypto_exit_proc();
965 }
966
967 module_init(crypto_algapi_init);
968 module_exit(crypto_algapi_exit);
969
970 MODULE_LICENSE("GPL");
971 MODULE_DESCRIPTION("Cryptographic algorithms API");