crypto: tcrypt - do not attempt to write to readonly variable
[linux-2.6.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 void crypto_remove_final(struct list_head *list);
26
27 static LIST_HEAD(crypto_template_list);
28
29 void crypto_larval_error(const char *name, u32 type, u32 mask)
30 {
31         struct crypto_alg *alg;
32
33         alg = crypto_alg_lookup(name, type, mask);
34
35         if (alg) {
36                 if (crypto_is_larval(alg)) {
37                         struct crypto_larval *larval = (void *)alg;
38                         complete_all(&larval->completion);
39                 }
40                 crypto_mod_put(alg);
41         }
42 }
43 EXPORT_SYMBOL_GPL(crypto_larval_error);
44
45 static inline int crypto_set_driver_name(struct crypto_alg *alg)
46 {
47         static const char suffix[] = "-generic";
48         char *driver_name = alg->cra_driver_name;
49         int len;
50
51         if (*driver_name)
52                 return 0;
53
54         len = strlcpy(driver_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
55         if (len + sizeof(suffix) > CRYPTO_MAX_ALG_NAME)
56                 return -ENAMETOOLONG;
57
58         memcpy(driver_name + len, suffix, sizeof(suffix));
59         return 0;
60 }
61
62 static int crypto_check_alg(struct crypto_alg *alg)
63 {
64         if (alg->cra_alignmask & (alg->cra_alignmask + 1))
65                 return -EINVAL;
66
67         if (alg->cra_blocksize > PAGE_SIZE / 8)
68                 return -EINVAL;
69
70         if (alg->cra_priority < 0)
71                 return -EINVAL;
72
73         return crypto_set_driver_name(alg);
74 }
75
76 static void crypto_destroy_instance(struct crypto_alg *alg)
77 {
78         struct crypto_instance *inst = (void *)alg;
79         struct crypto_template *tmpl = inst->tmpl;
80
81         tmpl->free(inst);
82         crypto_tmpl_put(tmpl);
83 }
84
85 static struct list_head *crypto_more_spawns(struct crypto_alg *alg,
86                                             struct list_head *stack,
87                                             struct list_head *top,
88                                             struct list_head *secondary_spawns)
89 {
90         struct crypto_spawn *spawn, *n;
91
92         if (list_empty(stack))
93                 return NULL;
94
95         spawn = list_first_entry(stack, struct crypto_spawn, list);
96         n = list_entry(spawn->list.next, struct crypto_spawn, list);
97
98         if (spawn->alg && &n->list != stack && !n->alg)
99                 n->alg = (n->list.next == stack) ? alg :
100                          &list_entry(n->list.next, struct crypto_spawn,
101                                      list)->inst->alg;
102
103         list_move(&spawn->list, secondary_spawns);
104
105         return &n->list == stack ? top : &n->inst->alg.cra_users;
106 }
107
108 static void crypto_remove_spawn(struct crypto_spawn *spawn,
109                                 struct list_head *list)
110 {
111         struct crypto_instance *inst = spawn->inst;
112         struct crypto_template *tmpl = inst->tmpl;
113
114         if (crypto_is_dead(&inst->alg))
115                 return;
116
117         inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
118         if (hlist_unhashed(&inst->list))
119                 return;
120
121         if (!tmpl || !crypto_tmpl_get(tmpl))
122                 return;
123
124         crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, &inst->alg);
125         list_move(&inst->alg.cra_list, list);
126         hlist_del(&inst->list);
127         inst->alg.cra_destroy = crypto_destroy_instance;
128
129         BUG_ON(!list_empty(&inst->alg.cra_users));
130 }
131
132 static void crypto_remove_spawns(struct crypto_alg *alg,
133                                  struct list_head *list,
134                                  struct crypto_alg *nalg)
135 {
136         u32 new_type = (nalg ?: alg)->cra_flags;
137         struct crypto_spawn *spawn, *n;
138         LIST_HEAD(secondary_spawns);
139         struct list_head *spawns;
140         LIST_HEAD(stack);
141         LIST_HEAD(top);
142
143         spawns = &alg->cra_users;
144         list_for_each_entry_safe(spawn, n, spawns, list) {
145                 if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
146                         continue;
147
148                 list_move(&spawn->list, &top);
149         }
150
151         spawns = &top;
152         do {
153                 while (!list_empty(spawns)) {
154                         struct crypto_instance *inst;
155
156                         spawn = list_first_entry(spawns, struct crypto_spawn,
157                                                  list);
158                         inst = spawn->inst;
159
160                         BUG_ON(&inst->alg == alg);
161
162                         list_move(&spawn->list, &stack);
163
164                         if (&inst->alg == nalg)
165                                 break;
166
167                         spawn->alg = NULL;
168                         spawns = &inst->alg.cra_users;
169                 }
170         } while ((spawns = crypto_more_spawns(alg, &stack, &top,
171                                               &secondary_spawns)));
172
173         list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {
174                 if (spawn->alg)
175                         list_move(&spawn->list, &spawn->alg->cra_users);
176                 else
177                         crypto_remove_spawn(spawn, list);
178         }
179 }
180
181 static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg)
182 {
183         struct crypto_alg *q;
184         struct crypto_larval *larval;
185         int ret = -EAGAIN;
186
187         if (crypto_is_dead(alg))
188                 goto err;
189
190         INIT_LIST_HEAD(&alg->cra_users);
191
192         /* No cheating! */
193         alg->cra_flags &= ~CRYPTO_ALG_TESTED;
194
195         ret = -EEXIST;
196
197         atomic_set(&alg->cra_refcnt, 1);
198         list_for_each_entry(q, &crypto_alg_list, cra_list) {
199                 if (q == alg)
200                         goto err;
201
202                 if (crypto_is_moribund(q))
203                         continue;
204
205                 if (crypto_is_larval(q)) {
206                         if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
207                                 goto err;
208                         continue;
209                 }
210
211                 if (!strcmp(q->cra_driver_name, alg->cra_name) ||
212                     !strcmp(q->cra_name, alg->cra_driver_name))
213                         goto err;
214         }
215
216         larval = crypto_larval_alloc(alg->cra_name,
217                                      alg->cra_flags | CRYPTO_ALG_TESTED, 0);
218         if (IS_ERR(larval))
219                 goto out;
220
221         ret = -ENOENT;
222         larval->adult = crypto_mod_get(alg);
223         if (!larval->adult)
224                 goto free_larval;
225
226         atomic_set(&larval->alg.cra_refcnt, 1);
227         memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
228                CRYPTO_MAX_ALG_NAME);
229         larval->alg.cra_priority = alg->cra_priority;
230
231         list_add(&alg->cra_list, &crypto_alg_list);
232         list_add(&larval->alg.cra_list, &crypto_alg_list);
233
234 out:
235         return larval;
236
237 free_larval:
238         kfree(larval);
239 err:
240         larval = ERR_PTR(ret);
241         goto out;
242 }
243
244 void crypto_alg_tested(const char *name, int err)
245 {
246         struct crypto_larval *test;
247         struct crypto_alg *alg;
248         struct crypto_alg *q;
249         LIST_HEAD(list);
250
251         down_write(&crypto_alg_sem);
252         list_for_each_entry(q, &crypto_alg_list, cra_list) {
253                 if (crypto_is_moribund(q) || !crypto_is_larval(q))
254                         continue;
255
256                 test = (struct crypto_larval *)q;
257
258                 if (!strcmp(q->cra_driver_name, name))
259                         goto found;
260         }
261
262         printk(KERN_ERR "alg: Unexpected test result for %s: %d\n", name, err);
263         goto unlock;
264
265 found:
266         q->cra_flags |= CRYPTO_ALG_DEAD;
267         alg = test->adult;
268         if (err || list_empty(&alg->cra_list))
269                 goto complete;
270
271         alg->cra_flags |= CRYPTO_ALG_TESTED;
272
273         list_for_each_entry(q, &crypto_alg_list, cra_list) {
274                 if (q == alg)
275                         continue;
276
277                 if (crypto_is_moribund(q))
278                         continue;
279
280                 if (crypto_is_larval(q)) {
281                         struct crypto_larval *larval = (void *)q;
282
283                         /*
284                          * Check to see if either our generic name or
285                          * specific name can satisfy the name requested
286                          * by the larval entry q.
287                          */
288                         if (strcmp(alg->cra_name, q->cra_name) &&
289                             strcmp(alg->cra_driver_name, q->cra_name))
290                                 continue;
291
292                         if (larval->adult)
293                                 continue;
294                         if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
295                                 continue;
296                         if (!crypto_mod_get(alg))
297                                 continue;
298
299                         larval->adult = alg;
300                         complete_all(&larval->completion);
301                         continue;
302                 }
303
304                 if (strcmp(alg->cra_name, q->cra_name))
305                         continue;
306
307                 if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
308                     q->cra_priority > alg->cra_priority)
309                         continue;
310
311                 crypto_remove_spawns(q, &list, alg);
312         }
313
314 complete:
315         complete_all(&test->completion);
316
317 unlock:
318         up_write(&crypto_alg_sem);
319
320         crypto_remove_final(&list);
321 }
322 EXPORT_SYMBOL_GPL(crypto_alg_tested);
323
324 static void crypto_remove_final(struct list_head *list)
325 {
326         struct crypto_alg *alg;
327         struct crypto_alg *n;
328
329         list_for_each_entry_safe(alg, n, list, cra_list) {
330                 list_del_init(&alg->cra_list);
331                 crypto_alg_put(alg);
332         }
333 }
334
335 static void crypto_wait_for_test(struct crypto_larval *larval)
336 {
337         int err;
338
339         err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult);
340         if (err != NOTIFY_STOP) {
341                 if (WARN_ON(err != NOTIFY_DONE))
342                         goto out;
343                 crypto_alg_tested(larval->alg.cra_driver_name, 0);
344         }
345
346         err = wait_for_completion_interruptible(&larval->completion);
347         WARN_ON(err);
348
349 out:
350         crypto_larval_kill(&larval->alg);
351 }
352
353 int crypto_register_alg(struct crypto_alg *alg)
354 {
355         struct crypto_larval *larval;
356         int err;
357
358         err = crypto_check_alg(alg);
359         if (err)
360                 return err;
361
362         down_write(&crypto_alg_sem);
363         larval = __crypto_register_alg(alg);
364         up_write(&crypto_alg_sem);
365
366         if (IS_ERR(larval))
367                 return PTR_ERR(larval);
368
369         crypto_wait_for_test(larval);
370         return 0;
371 }
372 EXPORT_SYMBOL_GPL(crypto_register_alg);
373
374 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
375 {
376         if (unlikely(list_empty(&alg->cra_list)))
377                 return -ENOENT;
378
379         alg->cra_flags |= CRYPTO_ALG_DEAD;
380
381         crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, alg);
382         list_del_init(&alg->cra_list);
383         crypto_remove_spawns(alg, list, NULL);
384
385         return 0;
386 }
387
388 int crypto_unregister_alg(struct crypto_alg *alg)
389 {
390         int ret;
391         LIST_HEAD(list);
392
393         down_write(&crypto_alg_sem);
394         ret = crypto_remove_alg(alg, &list);
395         up_write(&crypto_alg_sem);
396
397         if (ret)
398                 return ret;
399
400         BUG_ON(atomic_read(&alg->cra_refcnt) != 1);
401         if (alg->cra_destroy)
402                 alg->cra_destroy(alg);
403
404         crypto_remove_final(&list);
405         return 0;
406 }
407 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
408
409 int crypto_register_template(struct crypto_template *tmpl)
410 {
411         struct crypto_template *q;
412         int err = -EEXIST;
413
414         down_write(&crypto_alg_sem);
415
416         list_for_each_entry(q, &crypto_template_list, list) {
417                 if (q == tmpl)
418                         goto out;
419         }
420
421         list_add(&tmpl->list, &crypto_template_list);
422         crypto_notify(CRYPTO_MSG_TMPL_REGISTER, tmpl);
423         err = 0;
424 out:
425         up_write(&crypto_alg_sem);
426         return err;
427 }
428 EXPORT_SYMBOL_GPL(crypto_register_template);
429
430 void crypto_unregister_template(struct crypto_template *tmpl)
431 {
432         struct crypto_instance *inst;
433         struct hlist_node *p, *n;
434         struct hlist_head *list;
435         LIST_HEAD(users);
436
437         down_write(&crypto_alg_sem);
438
439         BUG_ON(list_empty(&tmpl->list));
440         list_del_init(&tmpl->list);
441
442         list = &tmpl->instances;
443         hlist_for_each_entry(inst, p, list, list) {
444                 int err = crypto_remove_alg(&inst->alg, &users);
445                 BUG_ON(err);
446         }
447
448         crypto_notify(CRYPTO_MSG_TMPL_UNREGISTER, tmpl);
449
450         up_write(&crypto_alg_sem);
451
452         hlist_for_each_entry_safe(inst, p, n, list, list) {
453                 BUG_ON(atomic_read(&inst->alg.cra_refcnt) != 1);
454                 tmpl->free(inst);
455         }
456         crypto_remove_final(&users);
457 }
458 EXPORT_SYMBOL_GPL(crypto_unregister_template);
459
460 static struct crypto_template *__crypto_lookup_template(const char *name)
461 {
462         struct crypto_template *q, *tmpl = NULL;
463
464         down_read(&crypto_alg_sem);
465         list_for_each_entry(q, &crypto_template_list, list) {
466                 if (strcmp(q->name, name))
467                         continue;
468                 if (unlikely(!crypto_tmpl_get(q)))
469                         continue;
470
471                 tmpl = q;
472                 break;
473         }
474         up_read(&crypto_alg_sem);
475
476         return tmpl;
477 }
478
479 struct crypto_template *crypto_lookup_template(const char *name)
480 {
481         return try_then_request_module(__crypto_lookup_template(name), name);
482 }
483 EXPORT_SYMBOL_GPL(crypto_lookup_template);
484
485 int crypto_register_instance(struct crypto_template *tmpl,
486                              struct crypto_instance *inst)
487 {
488         struct crypto_larval *larval;
489         int err;
490
491         err = crypto_check_alg(&inst->alg);
492         if (err)
493                 goto err;
494
495         inst->alg.cra_module = tmpl->module;
496
497         down_write(&crypto_alg_sem);
498
499         larval = __crypto_register_alg(&inst->alg);
500         if (IS_ERR(larval))
501                 goto unlock;
502
503         hlist_add_head(&inst->list, &tmpl->instances);
504         inst->tmpl = tmpl;
505
506 unlock:
507         up_write(&crypto_alg_sem);
508
509         err = PTR_ERR(larval);
510         if (IS_ERR(larval))
511                 goto err;
512
513         crypto_wait_for_test(larval);
514         err = 0;
515
516 err:
517         return err;
518 }
519 EXPORT_SYMBOL_GPL(crypto_register_instance);
520
521 int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg,
522                       struct crypto_instance *inst, u32 mask)
523 {
524         int err = -EAGAIN;
525
526         spawn->inst = inst;
527         spawn->mask = mask;
528
529         down_write(&crypto_alg_sem);
530         if (!crypto_is_moribund(alg)) {
531                 list_add(&spawn->list, &alg->cra_users);
532                 spawn->alg = alg;
533                 err = 0;
534         }
535         up_write(&crypto_alg_sem);
536
537         return err;
538 }
539 EXPORT_SYMBOL_GPL(crypto_init_spawn);
540
541 int crypto_init_spawn2(struct crypto_spawn *spawn, struct crypto_alg *alg,
542                        struct crypto_instance *inst,
543                        const struct crypto_type *frontend)
544 {
545         int err = -EINVAL;
546
547         if ((alg->cra_flags ^ frontend->type) & frontend->maskset)
548                 goto out;
549
550         spawn->frontend = frontend;
551         err = crypto_init_spawn(spawn, alg, inst, frontend->maskset);
552
553 out:
554         return err;
555 }
556 EXPORT_SYMBOL_GPL(crypto_init_spawn2);
557
558 void crypto_drop_spawn(struct crypto_spawn *spawn)
559 {
560         if (!spawn->alg)
561                 return;
562
563         down_write(&crypto_alg_sem);
564         list_del(&spawn->list);
565         up_write(&crypto_alg_sem);
566 }
567 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
568
569 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
570 {
571         struct crypto_alg *alg;
572         struct crypto_alg *alg2;
573
574         down_read(&crypto_alg_sem);
575         alg = spawn->alg;
576         alg2 = alg;
577         if (alg2)
578                 alg2 = crypto_mod_get(alg2);
579         up_read(&crypto_alg_sem);
580
581         if (!alg2) {
582                 if (alg)
583                         crypto_shoot_alg(alg);
584                 return ERR_PTR(-EAGAIN);
585         }
586
587         return alg;
588 }
589
590 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
591                                     u32 mask)
592 {
593         struct crypto_alg *alg;
594         struct crypto_tfm *tfm;
595
596         alg = crypto_spawn_alg(spawn);
597         if (IS_ERR(alg))
598                 return ERR_CAST(alg);
599
600         tfm = ERR_PTR(-EINVAL);
601         if (unlikely((alg->cra_flags ^ type) & mask))
602                 goto out_put_alg;
603
604         tfm = __crypto_alloc_tfm(alg, type, mask);
605         if (IS_ERR(tfm))
606                 goto out_put_alg;
607
608         return tfm;
609
610 out_put_alg:
611         crypto_mod_put(alg);
612         return tfm;
613 }
614 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
615
616 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
617 {
618         struct crypto_alg *alg;
619         struct crypto_tfm *tfm;
620
621         alg = crypto_spawn_alg(spawn);
622         if (IS_ERR(alg))
623                 return ERR_CAST(alg);
624
625         tfm = crypto_create_tfm(alg, spawn->frontend);
626         if (IS_ERR(tfm))
627                 goto out_put_alg;
628
629         return tfm;
630
631 out_put_alg:
632         crypto_mod_put(alg);
633         return tfm;
634 }
635 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
636
637 int crypto_register_notifier(struct notifier_block *nb)
638 {
639         return blocking_notifier_chain_register(&crypto_chain, nb);
640 }
641 EXPORT_SYMBOL_GPL(crypto_register_notifier);
642
643 int crypto_unregister_notifier(struct notifier_block *nb)
644 {
645         return blocking_notifier_chain_unregister(&crypto_chain, nb);
646 }
647 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
648
649 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
650 {
651         struct rtattr *rta = tb[0];
652         struct crypto_attr_type *algt;
653
654         if (!rta)
655                 return ERR_PTR(-ENOENT);
656         if (RTA_PAYLOAD(rta) < sizeof(*algt))
657                 return ERR_PTR(-EINVAL);
658         if (rta->rta_type != CRYPTOA_TYPE)
659                 return ERR_PTR(-EINVAL);
660
661         algt = RTA_DATA(rta);
662
663         return algt;
664 }
665 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
666
667 int crypto_check_attr_type(struct rtattr **tb, u32 type)
668 {
669         struct crypto_attr_type *algt;
670
671         algt = crypto_get_attr_type(tb);
672         if (IS_ERR(algt))
673                 return PTR_ERR(algt);
674
675         if ((algt->type ^ type) & algt->mask)
676                 return -EINVAL;
677
678         return 0;
679 }
680 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
681
682 const char *crypto_attr_alg_name(struct rtattr *rta)
683 {
684         struct crypto_attr_alg *alga;
685
686         if (!rta)
687                 return ERR_PTR(-ENOENT);
688         if (RTA_PAYLOAD(rta) < sizeof(*alga))
689                 return ERR_PTR(-EINVAL);
690         if (rta->rta_type != CRYPTOA_ALG)
691                 return ERR_PTR(-EINVAL);
692
693         alga = RTA_DATA(rta);
694         alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
695
696         return alga->name;
697 }
698 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
699
700 struct crypto_alg *crypto_attr_alg2(struct rtattr *rta,
701                                     const struct crypto_type *frontend,
702                                     u32 type, u32 mask)
703 {
704         const char *name;
705         int err;
706
707         name = crypto_attr_alg_name(rta);
708         err = PTR_ERR(name);
709         if (IS_ERR(name))
710                 return ERR_PTR(err);
711
712         return crypto_find_alg(name, frontend, type, mask);
713 }
714 EXPORT_SYMBOL_GPL(crypto_attr_alg2);
715
716 int crypto_attr_u32(struct rtattr *rta, u32 *num)
717 {
718         struct crypto_attr_u32 *nu32;
719
720         if (!rta)
721                 return -ENOENT;
722         if (RTA_PAYLOAD(rta) < sizeof(*nu32))
723                 return -EINVAL;
724         if (rta->rta_type != CRYPTOA_U32)
725                 return -EINVAL;
726
727         nu32 = RTA_DATA(rta);
728         *num = nu32->num;
729
730         return 0;
731 }
732 EXPORT_SYMBOL_GPL(crypto_attr_u32);
733
734 void *crypto_alloc_instance2(const char *name, struct crypto_alg *alg,
735                              unsigned int head)
736 {
737         struct crypto_instance *inst;
738         char *p;
739         int err;
740
741         p = kzalloc(head + sizeof(*inst) + sizeof(struct crypto_spawn),
742                     GFP_KERNEL);
743         if (!p)
744                 return ERR_PTR(-ENOMEM);
745
746         inst = (void *)(p + head);
747
748         err = -ENAMETOOLONG;
749         if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
750                      alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
751                 goto err_free_inst;
752
753         if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
754                      name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
755                 goto err_free_inst;
756
757         return p;
758
759 err_free_inst:
760         kfree(p);
761         return ERR_PTR(err);
762 }
763 EXPORT_SYMBOL_GPL(crypto_alloc_instance2);
764
765 struct crypto_instance *crypto_alloc_instance(const char *name,
766                                               struct crypto_alg *alg)
767 {
768         struct crypto_instance *inst;
769         struct crypto_spawn *spawn;
770         int err;
771
772         inst = crypto_alloc_instance2(name, alg, 0);
773         if (IS_ERR(inst))
774                 goto out;
775
776         spawn = crypto_instance_ctx(inst);
777         err = crypto_init_spawn(spawn, alg, inst,
778                                 CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
779
780         if (err)
781                 goto err_free_inst;
782
783         return inst;
784
785 err_free_inst:
786         kfree(inst);
787         inst = ERR_PTR(err);
788
789 out:
790         return inst;
791 }
792 EXPORT_SYMBOL_GPL(crypto_alloc_instance);
793
794 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
795 {
796         INIT_LIST_HEAD(&queue->list);
797         queue->backlog = &queue->list;
798         queue->qlen = 0;
799         queue->max_qlen = max_qlen;
800 }
801 EXPORT_SYMBOL_GPL(crypto_init_queue);
802
803 int crypto_enqueue_request(struct crypto_queue *queue,
804                            struct crypto_async_request *request)
805 {
806         int err = -EINPROGRESS;
807
808         if (unlikely(queue->qlen >= queue->max_qlen)) {
809                 err = -EBUSY;
810                 if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG))
811                         goto out;
812                 if (queue->backlog == &queue->list)
813                         queue->backlog = &request->list;
814         }
815
816         queue->qlen++;
817         list_add_tail(&request->list, &queue->list);
818
819 out:
820         return err;
821 }
822 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
823
824 void *__crypto_dequeue_request(struct crypto_queue *queue, unsigned int offset)
825 {
826         struct list_head *request;
827
828         if (unlikely(!queue->qlen))
829                 return NULL;
830
831         queue->qlen--;
832
833         if (queue->backlog != &queue->list)
834                 queue->backlog = queue->backlog->next;
835
836         request = queue->list.next;
837         list_del(request);
838
839         return (char *)list_entry(request, struct crypto_async_request, list) -
840                offset;
841 }
842 EXPORT_SYMBOL_GPL(__crypto_dequeue_request);
843
844 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
845 {
846         return __crypto_dequeue_request(queue, 0);
847 }
848 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
849
850 int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm)
851 {
852         struct crypto_async_request *req;
853
854         list_for_each_entry(req, &queue->list, list) {
855                 if (req->tfm == tfm)
856                         return 1;
857         }
858
859         return 0;
860 }
861 EXPORT_SYMBOL_GPL(crypto_tfm_in_queue);
862
863 static inline void crypto_inc_byte(u8 *a, unsigned int size)
864 {
865         u8 *b = (a + size);
866         u8 c;
867
868         for (; size; size--) {
869                 c = *--b + 1;
870                 *b = c;
871                 if (c)
872                         break;
873         }
874 }
875
876 void crypto_inc(u8 *a, unsigned int size)
877 {
878         __be32 *b = (__be32 *)(a + size);
879         u32 c;
880
881         for (; size >= 4; size -= 4) {
882                 c = be32_to_cpu(*--b) + 1;
883                 *b = cpu_to_be32(c);
884                 if (c)
885                         return;
886         }
887
888         crypto_inc_byte(a, size);
889 }
890 EXPORT_SYMBOL_GPL(crypto_inc);
891
892 static inline void crypto_xor_byte(u8 *a, const u8 *b, unsigned int size)
893 {
894         for (; size; size--)
895                 *a++ ^= *b++;
896 }
897
898 void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
899 {
900         u32 *a = (u32 *)dst;
901         u32 *b = (u32 *)src;
902
903         for (; size >= 4; size -= 4)
904                 *a++ ^= *b++;
905
906         crypto_xor_byte((u8 *)a, (u8 *)b, size);
907 }
908 EXPORT_SYMBOL_GPL(crypto_xor);
909
910 static int __init crypto_algapi_init(void)
911 {
912         crypto_init_proc();
913         return 0;
914 }
915
916 static void __exit crypto_algapi_exit(void)
917 {
918         crypto_exit_proc();
919 }
920
921 module_init(crypto_algapi_init);
922 module_exit(crypto_algapi_exit);
923
924 MODULE_LICENSE("GPL");
925 MODULE_DESCRIPTION("Cryptographic algorithms API");