p54: fix queue stall due to underrun
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / crypto / algapi.c
blob56c62e2858d56a9eee11b9167fe8362a71a7c6c1
1 /*
2 * Cryptographic API for algorithms (i.e., low-level API).
4 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
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.
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>
22 #include "internal.h"
24 static void crypto_remove_final(struct list_head *list);
26 static LIST_HEAD(crypto_template_list);
28 void crypto_larval_error(const char *name, u32 type, u32 mask)
30 struct crypto_alg *alg;
32 alg = crypto_alg_lookup(name, type, mask);
34 if (alg) {
35 if (crypto_is_larval(alg)) {
36 struct crypto_larval *larval = (void *)alg;
37 complete_all(&larval->completion);
39 crypto_mod_put(alg);
42 EXPORT_SYMBOL_GPL(crypto_larval_error);
44 static inline int crypto_set_driver_name(struct crypto_alg *alg)
46 static const char suffix[] = "-generic";
47 char *driver_name = alg->cra_driver_name;
48 int len;
50 if (*driver_name)
51 return 0;
53 len = strlcpy(driver_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
54 if (len + sizeof(suffix) > CRYPTO_MAX_ALG_NAME)
55 return -ENAMETOOLONG;
57 memcpy(driver_name + len, suffix, sizeof(suffix));
58 return 0;
61 static int crypto_check_alg(struct crypto_alg *alg)
63 if (alg->cra_alignmask & (alg->cra_alignmask + 1))
64 return -EINVAL;
66 if (alg->cra_blocksize > PAGE_SIZE / 8)
67 return -EINVAL;
69 if (alg->cra_priority < 0)
70 return -EINVAL;
72 return crypto_set_driver_name(alg);
75 static void crypto_destroy_instance(struct crypto_alg *alg)
77 struct crypto_instance *inst = (void *)alg;
78 struct crypto_template *tmpl = inst->tmpl;
80 tmpl->free(inst);
81 crypto_tmpl_put(tmpl);
84 static void crypto_remove_spawn(struct crypto_spawn *spawn,
85 struct list_head *list,
86 struct list_head *secondary_spawns)
88 struct crypto_instance *inst = spawn->inst;
89 struct crypto_template *tmpl = inst->tmpl;
91 list_del_init(&spawn->list);
92 spawn->alg = NULL;
94 if (crypto_is_dead(&inst->alg))
95 return;
97 inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
98 if (hlist_unhashed(&inst->list))
99 return;
101 if (!tmpl || !crypto_tmpl_get(tmpl))
102 return;
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;
109 list_splice(&inst->alg.cra_users, secondary_spawns);
112 static void crypto_remove_spawns(struct list_head *spawns,
113 struct list_head *list, u32 new_type)
115 struct crypto_spawn *spawn, *n;
116 LIST_HEAD(secondary_spawns);
118 list_for_each_entry_safe(spawn, n, spawns, list) {
119 if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
120 continue;
122 crypto_remove_spawn(spawn, list, &secondary_spawns);
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);
131 static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg)
133 struct crypto_alg *q;
134 struct crypto_larval *larval;
135 int ret = -EAGAIN;
137 if (crypto_is_dead(alg))
138 goto err;
140 INIT_LIST_HEAD(&alg->cra_users);
142 /* No cheating! */
143 alg->cra_flags &= ~CRYPTO_ALG_TESTED;
145 ret = -EEXIST;
147 atomic_set(&alg->cra_refcnt, 1);
148 list_for_each_entry(q, &crypto_alg_list, cra_list) {
149 if (q == alg)
150 goto err;
152 if (crypto_is_moribund(q))
153 continue;
155 if (crypto_is_larval(q)) {
156 if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
157 goto err;
158 continue;
161 if (!strcmp(q->cra_driver_name, alg->cra_name) ||
162 !strcmp(q->cra_name, alg->cra_driver_name))
163 goto err;
166 larval = crypto_larval_alloc(alg->cra_name,
167 alg->cra_flags | CRYPTO_ALG_TESTED, 0);
168 if (IS_ERR(larval))
169 goto out;
171 ret = -ENOENT;
172 larval->adult = crypto_mod_get(alg);
173 if (!larval->adult)
174 goto free_larval;
176 atomic_set(&larval->alg.cra_refcnt, 1);
177 memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
178 CRYPTO_MAX_ALG_NAME);
179 larval->alg.cra_priority = alg->cra_priority;
181 list_add(&alg->cra_list, &crypto_alg_list);
182 list_add(&larval->alg.cra_list, &crypto_alg_list);
184 out:
185 return larval;
187 free_larval:
188 kfree(larval);
189 err:
190 larval = ERR_PTR(ret);
191 goto out;
194 void crypto_alg_tested(const char *name, int err)
196 struct crypto_larval *test;
197 struct crypto_alg *alg;
198 struct crypto_alg *q;
199 LIST_HEAD(list);
201 down_write(&crypto_alg_sem);
202 list_for_each_entry(q, &crypto_alg_list, cra_list) {
203 if (crypto_is_moribund(q) || !crypto_is_larval(q))
204 continue;
206 test = (struct crypto_larval *)q;
208 if (!strcmp(q->cra_driver_name, name))
209 goto found;
212 printk(KERN_ERR "alg: Unexpected test result for %s: %d\n", name, err);
213 goto unlock;
215 found:
216 q->cra_flags |= CRYPTO_ALG_DEAD;
217 alg = test->adult;
218 if (err || list_empty(&alg->cra_list))
219 goto complete;
221 alg->cra_flags |= CRYPTO_ALG_TESTED;
223 list_for_each_entry(q, &crypto_alg_list, cra_list) {
224 if (q == alg)
225 continue;
227 if (crypto_is_moribund(q))
228 continue;
230 if (crypto_is_larval(q)) {
231 struct crypto_larval *larval = (void *)q;
234 * Check to see if either our generic name or
235 * specific name can satisfy the name requested
236 * by the larval entry q.
238 if (strcmp(alg->cra_name, q->cra_name) &&
239 strcmp(alg->cra_driver_name, q->cra_name))
240 continue;
242 if (larval->adult)
243 continue;
244 if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
245 continue;
246 if (!crypto_mod_get(alg))
247 continue;
249 larval->adult = alg;
250 complete_all(&larval->completion);
251 continue;
254 if (strcmp(alg->cra_name, q->cra_name))
255 continue;
257 if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
258 q->cra_priority > alg->cra_priority)
259 continue;
261 crypto_remove_spawns(&q->cra_users, &list, alg->cra_flags);
264 complete:
265 complete_all(&test->completion);
267 unlock:
268 up_write(&crypto_alg_sem);
270 crypto_remove_final(&list);
272 EXPORT_SYMBOL_GPL(crypto_alg_tested);
274 static void crypto_remove_final(struct list_head *list)
276 struct crypto_alg *alg;
277 struct crypto_alg *n;
279 list_for_each_entry_safe(alg, n, list, cra_list) {
280 list_del_init(&alg->cra_list);
281 crypto_alg_put(alg);
285 static void crypto_wait_for_test(struct crypto_larval *larval)
287 int err;
289 err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult);
290 if (err != NOTIFY_STOP) {
291 if (WARN_ON(err != NOTIFY_DONE))
292 goto out;
293 crypto_alg_tested(larval->alg.cra_driver_name, 0);
296 err = wait_for_completion_interruptible(&larval->completion);
297 WARN_ON(err);
299 out:
300 crypto_larval_kill(&larval->alg);
303 int crypto_register_alg(struct crypto_alg *alg)
305 struct crypto_larval *larval;
306 int err;
308 err = crypto_check_alg(alg);
309 if (err)
310 return err;
312 down_write(&crypto_alg_sem);
313 larval = __crypto_register_alg(alg);
314 up_write(&crypto_alg_sem);
316 if (IS_ERR(larval))
317 return PTR_ERR(larval);
319 crypto_wait_for_test(larval);
320 return 0;
322 EXPORT_SYMBOL_GPL(crypto_register_alg);
324 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
326 if (unlikely(list_empty(&alg->cra_list)))
327 return -ENOENT;
329 alg->cra_flags |= CRYPTO_ALG_DEAD;
331 crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, alg);
332 list_del_init(&alg->cra_list);
333 crypto_remove_spawns(&alg->cra_users, list, alg->cra_flags);
335 return 0;
338 int crypto_unregister_alg(struct crypto_alg *alg)
340 int ret;
341 LIST_HEAD(list);
343 down_write(&crypto_alg_sem);
344 ret = crypto_remove_alg(alg, &list);
345 up_write(&crypto_alg_sem);
347 if (ret)
348 return ret;
350 BUG_ON(atomic_read(&alg->cra_refcnt) != 1);
351 if (alg->cra_destroy)
352 alg->cra_destroy(alg);
354 crypto_remove_final(&list);
355 return 0;
357 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
359 int crypto_register_template(struct crypto_template *tmpl)
361 struct crypto_template *q;
362 int err = -EEXIST;
364 down_write(&crypto_alg_sem);
366 list_for_each_entry(q, &crypto_template_list, list) {
367 if (q == tmpl)
368 goto out;
371 list_add(&tmpl->list, &crypto_template_list);
372 crypto_notify(CRYPTO_MSG_TMPL_REGISTER, tmpl);
373 err = 0;
374 out:
375 up_write(&crypto_alg_sem);
376 return err;
378 EXPORT_SYMBOL_GPL(crypto_register_template);
380 void crypto_unregister_template(struct crypto_template *tmpl)
382 struct crypto_instance *inst;
383 struct hlist_node *p, *n;
384 struct hlist_head *list;
385 LIST_HEAD(users);
387 down_write(&crypto_alg_sem);
389 BUG_ON(list_empty(&tmpl->list));
390 list_del_init(&tmpl->list);
392 list = &tmpl->instances;
393 hlist_for_each_entry(inst, p, list, list) {
394 int err = crypto_remove_alg(&inst->alg, &users);
395 BUG_ON(err);
398 crypto_notify(CRYPTO_MSG_TMPL_UNREGISTER, tmpl);
400 up_write(&crypto_alg_sem);
402 hlist_for_each_entry_safe(inst, p, n, list, list) {
403 BUG_ON(atomic_read(&inst->alg.cra_refcnt) != 1);
404 tmpl->free(inst);
406 crypto_remove_final(&users);
408 EXPORT_SYMBOL_GPL(crypto_unregister_template);
410 static struct crypto_template *__crypto_lookup_template(const char *name)
412 struct crypto_template *q, *tmpl = NULL;
414 down_read(&crypto_alg_sem);
415 list_for_each_entry(q, &crypto_template_list, list) {
416 if (strcmp(q->name, name))
417 continue;
418 if (unlikely(!crypto_tmpl_get(q)))
419 continue;
421 tmpl = q;
422 break;
424 up_read(&crypto_alg_sem);
426 return tmpl;
429 struct crypto_template *crypto_lookup_template(const char *name)
431 return try_then_request_module(__crypto_lookup_template(name), name);
433 EXPORT_SYMBOL_GPL(crypto_lookup_template);
435 int crypto_register_instance(struct crypto_template *tmpl,
436 struct crypto_instance *inst)
438 struct crypto_larval *larval;
439 int err;
441 err = crypto_check_alg(&inst->alg);
442 if (err)
443 goto err;
445 inst->alg.cra_module = tmpl->module;
447 down_write(&crypto_alg_sem);
449 larval = __crypto_register_alg(&inst->alg);
450 if (IS_ERR(larval))
451 goto unlock;
453 hlist_add_head(&inst->list, &tmpl->instances);
454 inst->tmpl = tmpl;
456 unlock:
457 up_write(&crypto_alg_sem);
459 err = PTR_ERR(larval);
460 if (IS_ERR(larval))
461 goto err;
463 crypto_wait_for_test(larval);
464 err = 0;
466 err:
467 return err;
469 EXPORT_SYMBOL_GPL(crypto_register_instance);
471 int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg,
472 struct crypto_instance *inst, u32 mask)
474 int err = -EAGAIN;
476 spawn->inst = inst;
477 spawn->mask = mask;
479 down_write(&crypto_alg_sem);
480 if (!crypto_is_moribund(alg)) {
481 list_add(&spawn->list, &alg->cra_users);
482 spawn->alg = alg;
483 err = 0;
485 up_write(&crypto_alg_sem);
487 return err;
489 EXPORT_SYMBOL_GPL(crypto_init_spawn);
491 void crypto_drop_spawn(struct crypto_spawn *spawn)
493 down_write(&crypto_alg_sem);
494 list_del(&spawn->list);
495 up_write(&crypto_alg_sem);
497 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
499 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
500 u32 mask)
502 struct crypto_alg *alg;
503 struct crypto_alg *alg2;
504 struct crypto_tfm *tfm;
506 down_read(&crypto_alg_sem);
507 alg = spawn->alg;
508 alg2 = alg;
509 if (alg2)
510 alg2 = crypto_mod_get(alg2);
511 up_read(&crypto_alg_sem);
513 if (!alg2) {
514 if (alg)
515 crypto_shoot_alg(alg);
516 return ERR_PTR(-EAGAIN);
519 tfm = ERR_PTR(-EINVAL);
520 if (unlikely((alg->cra_flags ^ type) & mask))
521 goto out_put_alg;
523 tfm = __crypto_alloc_tfm(alg, type, mask);
524 if (IS_ERR(tfm))
525 goto out_put_alg;
527 return tfm;
529 out_put_alg:
530 crypto_mod_put(alg);
531 return tfm;
533 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
535 int crypto_register_notifier(struct notifier_block *nb)
537 return blocking_notifier_chain_register(&crypto_chain, nb);
539 EXPORT_SYMBOL_GPL(crypto_register_notifier);
541 int crypto_unregister_notifier(struct notifier_block *nb)
543 return blocking_notifier_chain_unregister(&crypto_chain, nb);
545 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
547 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
549 struct rtattr *rta = tb[0];
550 struct crypto_attr_type *algt;
552 if (!rta)
553 return ERR_PTR(-ENOENT);
554 if (RTA_PAYLOAD(rta) < sizeof(*algt))
555 return ERR_PTR(-EINVAL);
556 if (rta->rta_type != CRYPTOA_TYPE)
557 return ERR_PTR(-EINVAL);
559 algt = RTA_DATA(rta);
561 return algt;
563 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
565 int crypto_check_attr_type(struct rtattr **tb, u32 type)
567 struct crypto_attr_type *algt;
569 algt = crypto_get_attr_type(tb);
570 if (IS_ERR(algt))
571 return PTR_ERR(algt);
573 if ((algt->type ^ type) & algt->mask)
574 return -EINVAL;
576 return 0;
578 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
580 const char *crypto_attr_alg_name(struct rtattr *rta)
582 struct crypto_attr_alg *alga;
584 if (!rta)
585 return ERR_PTR(-ENOENT);
586 if (RTA_PAYLOAD(rta) < sizeof(*alga))
587 return ERR_PTR(-EINVAL);
588 if (rta->rta_type != CRYPTOA_ALG)
589 return ERR_PTR(-EINVAL);
591 alga = RTA_DATA(rta);
592 alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
594 return alga->name;
596 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
598 struct crypto_alg *crypto_attr_alg(struct rtattr *rta, u32 type, u32 mask)
600 const char *name;
601 int err;
603 name = crypto_attr_alg_name(rta);
604 err = PTR_ERR(name);
605 if (IS_ERR(name))
606 return ERR_PTR(err);
608 return crypto_alg_mod_lookup(name, type, mask);
610 EXPORT_SYMBOL_GPL(crypto_attr_alg);
612 int crypto_attr_u32(struct rtattr *rta, u32 *num)
614 struct crypto_attr_u32 *nu32;
616 if (!rta)
617 return -ENOENT;
618 if (RTA_PAYLOAD(rta) < sizeof(*nu32))
619 return -EINVAL;
620 if (rta->rta_type != CRYPTOA_U32)
621 return -EINVAL;
623 nu32 = RTA_DATA(rta);
624 *num = nu32->num;
626 return 0;
628 EXPORT_SYMBOL_GPL(crypto_attr_u32);
630 struct crypto_instance *crypto_alloc_instance(const char *name,
631 struct crypto_alg *alg)
633 struct crypto_instance *inst;
634 struct crypto_spawn *spawn;
635 int err;
637 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
638 if (!inst)
639 return ERR_PTR(-ENOMEM);
641 err = -ENAMETOOLONG;
642 if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
643 alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
644 goto err_free_inst;
646 if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
647 name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
648 goto err_free_inst;
650 spawn = crypto_instance_ctx(inst);
651 err = crypto_init_spawn(spawn, alg, inst,
652 CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
654 if (err)
655 goto err_free_inst;
657 return inst;
659 err_free_inst:
660 kfree(inst);
661 return ERR_PTR(err);
663 EXPORT_SYMBOL_GPL(crypto_alloc_instance);
665 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
667 INIT_LIST_HEAD(&queue->list);
668 queue->backlog = &queue->list;
669 queue->qlen = 0;
670 queue->max_qlen = max_qlen;
672 EXPORT_SYMBOL_GPL(crypto_init_queue);
674 int crypto_enqueue_request(struct crypto_queue *queue,
675 struct crypto_async_request *request)
677 int err = -EINPROGRESS;
679 if (unlikely(queue->qlen >= queue->max_qlen)) {
680 err = -EBUSY;
681 if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG))
682 goto out;
683 if (queue->backlog == &queue->list)
684 queue->backlog = &request->list;
687 queue->qlen++;
688 list_add_tail(&request->list, &queue->list);
690 out:
691 return err;
693 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
695 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
697 struct list_head *request;
699 if (unlikely(!queue->qlen))
700 return NULL;
702 queue->qlen--;
704 if (queue->backlog != &queue->list)
705 queue->backlog = queue->backlog->next;
707 request = queue->list.next;
708 list_del(request);
710 return list_entry(request, struct crypto_async_request, list);
712 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
714 int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm)
716 struct crypto_async_request *req;
718 list_for_each_entry(req, &queue->list, list) {
719 if (req->tfm == tfm)
720 return 1;
723 return 0;
725 EXPORT_SYMBOL_GPL(crypto_tfm_in_queue);
727 static inline void crypto_inc_byte(u8 *a, unsigned int size)
729 u8 *b = (a + size);
730 u8 c;
732 for (; size; size--) {
733 c = *--b + 1;
734 *b = c;
735 if (c)
736 break;
740 void crypto_inc(u8 *a, unsigned int size)
742 __be32 *b = (__be32 *)(a + size);
743 u32 c;
745 for (; size >= 4; size -= 4) {
746 c = be32_to_cpu(*--b) + 1;
747 *b = cpu_to_be32(c);
748 if (c)
749 return;
752 crypto_inc_byte(a, size);
754 EXPORT_SYMBOL_GPL(crypto_inc);
756 static inline void crypto_xor_byte(u8 *a, const u8 *b, unsigned int size)
758 for (; size; size--)
759 *a++ ^= *b++;
762 void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
764 u32 *a = (u32 *)dst;
765 u32 *b = (u32 *)src;
767 for (; size >= 4; size -= 4)
768 *a++ ^= *b++;
770 crypto_xor_byte((u8 *)a, (u8 *)b, size);
772 EXPORT_SYMBOL_GPL(crypto_xor);
774 static int __init crypto_algapi_init(void)
776 crypto_init_proc();
777 return 0;
780 static void __exit crypto_algapi_exit(void)
782 crypto_exit_proc();
785 module_init(crypto_algapi_init);
786 module_exit(crypto_algapi_exit);
788 MODULE_LICENSE("GPL");
789 MODULE_DESCRIPTION("Cryptographic algorithms API");