xref: /linux/crypto/algapi.c (revision ca70c24fb17b161a6096c584238cf81f664db45d)
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/fips.h>
16  #include <linux/init.h>
17  #include <linux/kernel.h>
18  #include <linux/list.h>
19  #include <linux/module.h>
20  #include <linux/rtnetlink.h>
21  #include <linux/slab.h>
22  #include <linux/string.h>
23  
24  #include "internal.h"
25  
26  static LIST_HEAD(crypto_template_list);
27  
28  static inline int crypto_set_driver_name(struct crypto_alg *alg)
29  {
30  	static const char suffix[] = "-generic";
31  	char *driver_name = alg->cra_driver_name;
32  	int len;
33  
34  	if (*driver_name)
35  		return 0;
36  
37  	len = strlcpy(driver_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
38  	if (len + sizeof(suffix) > CRYPTO_MAX_ALG_NAME)
39  		return -ENAMETOOLONG;
40  
41  	memcpy(driver_name + len, suffix, sizeof(suffix));
42  	return 0;
43  }
44  
45  static inline void crypto_check_module_sig(struct module *mod)
46  {
47  	if (fips_enabled && mod && !module_sig_ok(mod))
48  		panic("Module %s signature verification failed in FIPS mode\n",
49  		      module_name(mod));
50  }
51  
52  static int crypto_check_alg(struct crypto_alg *alg)
53  {
54  	crypto_check_module_sig(alg->cra_module);
55  
56  	if (alg->cra_alignmask & (alg->cra_alignmask + 1))
57  		return -EINVAL;
58  
59  	if (alg->cra_blocksize > PAGE_SIZE / 8)
60  		return -EINVAL;
61  
62  	if (alg->cra_priority < 0)
63  		return -EINVAL;
64  
65  	atomic_set(&alg->cra_refcnt, 1);
66  
67  	return crypto_set_driver_name(alg);
68  }
69  
70  static void crypto_free_instance(struct crypto_instance *inst)
71  {
72  	if (!inst->alg.cra_type->free) {
73  		inst->tmpl->free(inst);
74  		return;
75  	}
76  
77  	inst->alg.cra_type->free(inst);
78  }
79  
80  static void crypto_destroy_instance(struct crypto_alg *alg)
81  {
82  	struct crypto_instance *inst = (void *)alg;
83  	struct crypto_template *tmpl = inst->tmpl;
84  
85  	crypto_free_instance(inst);
86  	crypto_tmpl_put(tmpl);
87  }
88  
89  static struct list_head *crypto_more_spawns(struct crypto_alg *alg,
90  					    struct list_head *stack,
91  					    struct list_head *top,
92  					    struct list_head *secondary_spawns)
93  {
94  	struct crypto_spawn *spawn, *n;
95  
96  	spawn = list_first_entry_or_null(stack, struct crypto_spawn, list);
97  	if (!spawn)
98  		return NULL;
99  
100  	n = list_next_entry(spawn, list);
101  
102  	if (spawn->alg && &n->list != stack && !n->alg)
103  		n->alg = (n->list.next == stack) ? alg :
104  			 &list_next_entry(n, list)->inst->alg;
105  
106  	list_move(&spawn->list, secondary_spawns);
107  
108  	return &n->list == stack ? top : &n->inst->alg.cra_users;
109  }
110  
111  static void crypto_remove_instance(struct crypto_instance *inst,
112  				   struct list_head *list)
113  {
114  	struct crypto_template *tmpl = inst->tmpl;
115  
116  	if (crypto_is_dead(&inst->alg))
117  		return;
118  
119  	inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
120  	if (hlist_unhashed(&inst->list))
121  		return;
122  
123  	if (!tmpl || !crypto_tmpl_get(tmpl))
124  		return;
125  
126  	crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, &inst->alg);
127  	list_move(&inst->alg.cra_list, list);
128  	hlist_del(&inst->list);
129  	inst->alg.cra_destroy = crypto_destroy_instance;
130  
131  	BUG_ON(!list_empty(&inst->alg.cra_users));
132  }
133  
134  void crypto_remove_spawns(struct crypto_alg *alg, struct list_head *list,
135  			  struct crypto_alg *nalg)
136  {
137  	u32 new_type = (nalg ?: alg)->cra_flags;
138  	struct crypto_spawn *spawn, *n;
139  	LIST_HEAD(secondary_spawns);
140  	struct list_head *spawns;
141  	LIST_HEAD(stack);
142  	LIST_HEAD(top);
143  
144  	spawns = &alg->cra_users;
145  	list_for_each_entry_safe(spawn, n, spawns, list) {
146  		if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
147  			continue;
148  
149  		list_move(&spawn->list, &top);
150  	}
151  
152  	spawns = &top;
153  	do {
154  		while (!list_empty(spawns)) {
155  			struct crypto_instance *inst;
156  
157  			spawn = list_first_entry(spawns, struct crypto_spawn,
158  						 list);
159  			inst = spawn->inst;
160  
161  			BUG_ON(&inst->alg == alg);
162  
163  			list_move(&spawn->list, &stack);
164  
165  			if (&inst->alg == nalg)
166  				break;
167  
168  			spawn->alg = NULL;
169  			spawns = &inst->alg.cra_users;
170  		}
171  	} while ((spawns = crypto_more_spawns(alg, &stack, &top,
172  					      &secondary_spawns)));
173  
174  	list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {
175  		if (spawn->alg)
176  			list_move(&spawn->list, &spawn->alg->cra_users);
177  		else
178  			crypto_remove_instance(spawn->inst, list);
179  	}
180  }
181  EXPORT_SYMBOL_GPL(crypto_remove_spawns);
182  
183  static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg)
184  {
185  	struct crypto_alg *q;
186  	struct crypto_larval *larval;
187  	int ret = -EAGAIN;
188  
189  	if (crypto_is_dead(alg))
190  		goto err;
191  
192  	INIT_LIST_HEAD(&alg->cra_users);
193  
194  	/* No cheating! */
195  	alg->cra_flags &= ~CRYPTO_ALG_TESTED;
196  
197  	ret = -EEXIST;
198  
199  	list_for_each_entry(q, &crypto_alg_list, cra_list) {
200  		if (q == alg)
201  			goto err;
202  
203  		if (crypto_is_moribund(q))
204  			continue;
205  
206  		if (crypto_is_larval(q)) {
207  			if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
208  				goto err;
209  			continue;
210  		}
211  
212  		if (!strcmp(q->cra_driver_name, alg->cra_name) ||
213  		    !strcmp(q->cra_name, alg->cra_driver_name))
214  			goto err;
215  	}
216  
217  	larval = crypto_larval_alloc(alg->cra_name,
218  				     alg->cra_flags | CRYPTO_ALG_TESTED, 0);
219  	if (IS_ERR(larval))
220  		goto out;
221  
222  	ret = -ENOENT;
223  	larval->adult = crypto_mod_get(alg);
224  	if (!larval->adult)
225  		goto free_larval;
226  
227  	atomic_set(&larval->alg.cra_refcnt, 1);
228  	memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
229  	       CRYPTO_MAX_ALG_NAME);
230  	larval->alg.cra_priority = alg->cra_priority;
231  
232  	list_add(&alg->cra_list, &crypto_alg_list);
233  	list_add(&larval->alg.cra_list, &crypto_alg_list);
234  
235  out:
236  	return larval;
237  
238  free_larval:
239  	kfree(larval);
240  err:
241  	larval = ERR_PTR(ret);
242  	goto out;
243  }
244  
245  void crypto_alg_tested(const char *name, int err)
246  {
247  	struct crypto_larval *test;
248  	struct crypto_alg *alg;
249  	struct crypto_alg *q;
250  	LIST_HEAD(list);
251  
252  	down_write(&crypto_alg_sem);
253  	list_for_each_entry(q, &crypto_alg_list, cra_list) {
254  		if (crypto_is_moribund(q) || !crypto_is_larval(q))
255  			continue;
256  
257  		test = (struct crypto_larval *)q;
258  
259  		if (!strcmp(q->cra_driver_name, name))
260  			goto found;
261  	}
262  
263  	printk(KERN_ERR "alg: Unexpected test result for %s: %d\n", name, err);
264  	goto unlock;
265  
266  found:
267  	q->cra_flags |= CRYPTO_ALG_DEAD;
268  	alg = test->adult;
269  	if (err || list_empty(&alg->cra_list))
270  		goto complete;
271  
272  	alg->cra_flags |= CRYPTO_ALG_TESTED;
273  
274  	list_for_each_entry(q, &crypto_alg_list, cra_list) {
275  		if (q == alg)
276  			continue;
277  
278  		if (crypto_is_moribund(q))
279  			continue;
280  
281  		if (crypto_is_larval(q)) {
282  			struct crypto_larval *larval = (void *)q;
283  
284  			/*
285  			 * Check to see if either our generic name or
286  			 * specific name can satisfy the name requested
287  			 * by the larval entry q.
288  			 */
289  			if (strcmp(alg->cra_name, q->cra_name) &&
290  			    strcmp(alg->cra_driver_name, q->cra_name))
291  				continue;
292  
293  			if (larval->adult)
294  				continue;
295  			if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
296  				continue;
297  			if (!crypto_mod_get(alg))
298  				continue;
299  
300  			larval->adult = alg;
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  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  EXPORT_SYMBOL_GPL(crypto_remove_final);
335  
336  static void crypto_wait_for_test(struct crypto_larval *larval)
337  {
338  	int err;
339  
340  	err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult);
341  	if (err != NOTIFY_STOP) {
342  		if (WARN_ON(err != NOTIFY_DONE))
343  			goto out;
344  		crypto_alg_tested(larval->alg.cra_driver_name, 0);
345  	}
346  
347  	err = wait_for_completion_killable(&larval->completion);
348  	WARN_ON(err);
349  
350  out:
351  	crypto_larval_kill(&larval->alg);
352  }
353  
354  int crypto_register_alg(struct crypto_alg *alg)
355  {
356  	struct crypto_larval *larval;
357  	int err;
358  
359  	err = crypto_check_alg(alg);
360  	if (err)
361  		return err;
362  
363  	down_write(&crypto_alg_sem);
364  	larval = __crypto_register_alg(alg);
365  	up_write(&crypto_alg_sem);
366  
367  	if (IS_ERR(larval))
368  		return PTR_ERR(larval);
369  
370  	crypto_wait_for_test(larval);
371  	return 0;
372  }
373  EXPORT_SYMBOL_GPL(crypto_register_alg);
374  
375  static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
376  {
377  	if (unlikely(list_empty(&alg->cra_list)))
378  		return -ENOENT;
379  
380  	alg->cra_flags |= CRYPTO_ALG_DEAD;
381  
382  	crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, alg);
383  	list_del_init(&alg->cra_list);
384  	crypto_remove_spawns(alg, list, NULL);
385  
386  	return 0;
387  }
388  
389  int crypto_unregister_alg(struct crypto_alg *alg)
390  {
391  	int ret;
392  	LIST_HEAD(list);
393  
394  	down_write(&crypto_alg_sem);
395  	ret = crypto_remove_alg(alg, &list);
396  	up_write(&crypto_alg_sem);
397  
398  	if (ret)
399  		return ret;
400  
401  	BUG_ON(atomic_read(&alg->cra_refcnt) != 1);
402  	if (alg->cra_destroy)
403  		alg->cra_destroy(alg);
404  
405  	crypto_remove_final(&list);
406  	return 0;
407  }
408  EXPORT_SYMBOL_GPL(crypto_unregister_alg);
409  
410  int crypto_register_algs(struct crypto_alg *algs, int count)
411  {
412  	int i, ret;
413  
414  	for (i = 0; i < count; i++) {
415  		ret = crypto_register_alg(&algs[i]);
416  		if (ret)
417  			goto err;
418  	}
419  
420  	return 0;
421  
422  err:
423  	for (--i; i >= 0; --i)
424  		crypto_unregister_alg(&algs[i]);
425  
426  	return ret;
427  }
428  EXPORT_SYMBOL_GPL(crypto_register_algs);
429  
430  int crypto_unregister_algs(struct crypto_alg *algs, int count)
431  {
432  	int i, ret;
433  
434  	for (i = 0; i < count; i++) {
435  		ret = crypto_unregister_alg(&algs[i]);
436  		if (ret)
437  			pr_err("Failed to unregister %s %s: %d\n",
438  			       algs[i].cra_driver_name, algs[i].cra_name, ret);
439  	}
440  
441  	return 0;
442  }
443  EXPORT_SYMBOL_GPL(crypto_unregister_algs);
444  
445  int crypto_register_template(struct crypto_template *tmpl)
446  {
447  	struct crypto_template *q;
448  	int err = -EEXIST;
449  
450  	down_write(&crypto_alg_sem);
451  
452  	crypto_check_module_sig(tmpl->module);
453  
454  	list_for_each_entry(q, &crypto_template_list, list) {
455  		if (q == tmpl)
456  			goto out;
457  	}
458  
459  	list_add(&tmpl->list, &crypto_template_list);
460  	crypto_notify(CRYPTO_MSG_TMPL_REGISTER, tmpl);
461  	err = 0;
462  out:
463  	up_write(&crypto_alg_sem);
464  	return err;
465  }
466  EXPORT_SYMBOL_GPL(crypto_register_template);
467  
468  void crypto_unregister_template(struct crypto_template *tmpl)
469  {
470  	struct crypto_instance *inst;
471  	struct hlist_node *n;
472  	struct hlist_head *list;
473  	LIST_HEAD(users);
474  
475  	down_write(&crypto_alg_sem);
476  
477  	BUG_ON(list_empty(&tmpl->list));
478  	list_del_init(&tmpl->list);
479  
480  	list = &tmpl->instances;
481  	hlist_for_each_entry(inst, list, list) {
482  		int err = crypto_remove_alg(&inst->alg, &users);
483  
484  		BUG_ON(err);
485  	}
486  
487  	crypto_notify(CRYPTO_MSG_TMPL_UNREGISTER, tmpl);
488  
489  	up_write(&crypto_alg_sem);
490  
491  	hlist_for_each_entry_safe(inst, n, list, list) {
492  		BUG_ON(atomic_read(&inst->alg.cra_refcnt) != 1);
493  		crypto_free_instance(inst);
494  	}
495  	crypto_remove_final(&users);
496  }
497  EXPORT_SYMBOL_GPL(crypto_unregister_template);
498  
499  static struct crypto_template *__crypto_lookup_template(const char *name)
500  {
501  	struct crypto_template *q, *tmpl = NULL;
502  
503  	down_read(&crypto_alg_sem);
504  	list_for_each_entry(q, &crypto_template_list, list) {
505  		if (strcmp(q->name, name))
506  			continue;
507  		if (unlikely(!crypto_tmpl_get(q)))
508  			continue;
509  
510  		tmpl = q;
511  		break;
512  	}
513  	up_read(&crypto_alg_sem);
514  
515  	return tmpl;
516  }
517  
518  struct crypto_template *crypto_lookup_template(const char *name)
519  {
520  	return try_then_request_module(__crypto_lookup_template(name),
521  				       "crypto-%s", name);
522  }
523  EXPORT_SYMBOL_GPL(crypto_lookup_template);
524  
525  int crypto_register_instance(struct crypto_template *tmpl,
526  			     struct crypto_instance *inst)
527  {
528  	struct crypto_larval *larval;
529  	int err;
530  
531  	err = crypto_check_alg(&inst->alg);
532  	if (err)
533  		return err;
534  
535  	inst->alg.cra_module = tmpl->module;
536  	inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
537  
538  	if (unlikely(!crypto_mod_get(&inst->alg)))
539  		return -EAGAIN;
540  
541  	down_write(&crypto_alg_sem);
542  
543  	larval = __crypto_register_alg(&inst->alg);
544  	if (IS_ERR(larval))
545  		goto unlock;
546  
547  	hlist_add_head(&inst->list, &tmpl->instances);
548  	inst->tmpl = tmpl;
549  
550  unlock:
551  	up_write(&crypto_alg_sem);
552  
553  	err = PTR_ERR(larval);
554  	if (IS_ERR(larval))
555  		goto err;
556  
557  	crypto_wait_for_test(larval);
558  
559  	/* Remove instance if test failed */
560  	if (!(inst->alg.cra_flags & CRYPTO_ALG_TESTED))
561  		crypto_unregister_instance(inst);
562  	err = 0;
563  
564  err:
565  	crypto_mod_put(&inst->alg);
566  	return err;
567  }
568  EXPORT_SYMBOL_GPL(crypto_register_instance);
569  
570  int crypto_unregister_instance(struct crypto_instance *inst)
571  {
572  	LIST_HEAD(list);
573  
574  	down_write(&crypto_alg_sem);
575  
576  	crypto_remove_spawns(&inst->alg, &list, NULL);
577  	crypto_remove_instance(inst, &list);
578  
579  	up_write(&crypto_alg_sem);
580  
581  	crypto_remove_final(&list);
582  
583  	return 0;
584  }
585  EXPORT_SYMBOL_GPL(crypto_unregister_instance);
586  
587  int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg,
588  		      struct crypto_instance *inst, u32 mask)
589  {
590  	int err = -EAGAIN;
591  
592  	spawn->inst = inst;
593  	spawn->mask = mask;
594  
595  	down_write(&crypto_alg_sem);
596  	if (!crypto_is_moribund(alg)) {
597  		list_add(&spawn->list, &alg->cra_users);
598  		spawn->alg = alg;
599  		err = 0;
600  	}
601  	up_write(&crypto_alg_sem);
602  
603  	return err;
604  }
605  EXPORT_SYMBOL_GPL(crypto_init_spawn);
606  
607  int crypto_init_spawn2(struct crypto_spawn *spawn, struct crypto_alg *alg,
608  		       struct crypto_instance *inst,
609  		       const struct crypto_type *frontend)
610  {
611  	int err = -EINVAL;
612  
613  	if ((alg->cra_flags ^ frontend->type) & frontend->maskset)
614  		goto out;
615  
616  	spawn->frontend = frontend;
617  	err = crypto_init_spawn(spawn, alg, inst, frontend->maskset);
618  
619  out:
620  	return err;
621  }
622  EXPORT_SYMBOL_GPL(crypto_init_spawn2);
623  
624  int crypto_grab_spawn(struct crypto_spawn *spawn, const char *name,
625  		      u32 type, u32 mask)
626  {
627  	struct crypto_alg *alg;
628  	int err;
629  
630  	alg = crypto_find_alg(name, spawn->frontend, type, mask);
631  	if (IS_ERR(alg))
632  		return PTR_ERR(alg);
633  
634  	err = crypto_init_spawn(spawn, alg, spawn->inst, mask);
635  	crypto_mod_put(alg);
636  	return err;
637  }
638  EXPORT_SYMBOL_GPL(crypto_grab_spawn);
639  
640  void crypto_drop_spawn(struct crypto_spawn *spawn)
641  {
642  	if (!spawn->alg)
643  		return;
644  
645  	down_write(&crypto_alg_sem);
646  	list_del(&spawn->list);
647  	up_write(&crypto_alg_sem);
648  }
649  EXPORT_SYMBOL_GPL(crypto_drop_spawn);
650  
651  static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
652  {
653  	struct crypto_alg *alg;
654  	struct crypto_alg *alg2;
655  
656  	down_read(&crypto_alg_sem);
657  	alg = spawn->alg;
658  	alg2 = alg;
659  	if (alg2)
660  		alg2 = crypto_mod_get(alg2);
661  	up_read(&crypto_alg_sem);
662  
663  	if (!alg2) {
664  		if (alg)
665  			crypto_shoot_alg(alg);
666  		return ERR_PTR(-EAGAIN);
667  	}
668  
669  	return alg;
670  }
671  
672  struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
673  				    u32 mask)
674  {
675  	struct crypto_alg *alg;
676  	struct crypto_tfm *tfm;
677  
678  	alg = crypto_spawn_alg(spawn);
679  	if (IS_ERR(alg))
680  		return ERR_CAST(alg);
681  
682  	tfm = ERR_PTR(-EINVAL);
683  	if (unlikely((alg->cra_flags ^ type) & mask))
684  		goto out_put_alg;
685  
686  	tfm = __crypto_alloc_tfm(alg, type, mask);
687  	if (IS_ERR(tfm))
688  		goto out_put_alg;
689  
690  	return tfm;
691  
692  out_put_alg:
693  	crypto_mod_put(alg);
694  	return tfm;
695  }
696  EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
697  
698  void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
699  {
700  	struct crypto_alg *alg;
701  	struct crypto_tfm *tfm;
702  
703  	alg = crypto_spawn_alg(spawn);
704  	if (IS_ERR(alg))
705  		return ERR_CAST(alg);
706  
707  	tfm = crypto_create_tfm(alg, spawn->frontend);
708  	if (IS_ERR(tfm))
709  		goto out_put_alg;
710  
711  	return tfm;
712  
713  out_put_alg:
714  	crypto_mod_put(alg);
715  	return tfm;
716  }
717  EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
718  
719  int crypto_register_notifier(struct notifier_block *nb)
720  {
721  	return blocking_notifier_chain_register(&crypto_chain, nb);
722  }
723  EXPORT_SYMBOL_GPL(crypto_register_notifier);
724  
725  int crypto_unregister_notifier(struct notifier_block *nb)
726  {
727  	return blocking_notifier_chain_unregister(&crypto_chain, nb);
728  }
729  EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
730  
731  struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
732  {
733  	struct rtattr *rta = tb[0];
734  	struct crypto_attr_type *algt;
735  
736  	if (!rta)
737  		return ERR_PTR(-ENOENT);
738  	if (RTA_PAYLOAD(rta) < sizeof(*algt))
739  		return ERR_PTR(-EINVAL);
740  	if (rta->rta_type != CRYPTOA_TYPE)
741  		return ERR_PTR(-EINVAL);
742  
743  	algt = RTA_DATA(rta);
744  
745  	return algt;
746  }
747  EXPORT_SYMBOL_GPL(crypto_get_attr_type);
748  
749  int crypto_check_attr_type(struct rtattr **tb, u32 type)
750  {
751  	struct crypto_attr_type *algt;
752  
753  	algt = crypto_get_attr_type(tb);
754  	if (IS_ERR(algt))
755  		return PTR_ERR(algt);
756  
757  	if ((algt->type ^ type) & algt->mask)
758  		return -EINVAL;
759  
760  	return 0;
761  }
762  EXPORT_SYMBOL_GPL(crypto_check_attr_type);
763  
764  const char *crypto_attr_alg_name(struct rtattr *rta)
765  {
766  	struct crypto_attr_alg *alga;
767  
768  	if (!rta)
769  		return ERR_PTR(-ENOENT);
770  	if (RTA_PAYLOAD(rta) < sizeof(*alga))
771  		return ERR_PTR(-EINVAL);
772  	if (rta->rta_type != CRYPTOA_ALG)
773  		return ERR_PTR(-EINVAL);
774  
775  	alga = RTA_DATA(rta);
776  	alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
777  
778  	return alga->name;
779  }
780  EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
781  
782  struct crypto_alg *crypto_attr_alg2(struct rtattr *rta,
783  				    const struct crypto_type *frontend,
784  				    u32 type, u32 mask)
785  {
786  	const char *name;
787  
788  	name = crypto_attr_alg_name(rta);
789  	if (IS_ERR(name))
790  		return ERR_CAST(name);
791  
792  	return crypto_find_alg(name, frontend, type, mask);
793  }
794  EXPORT_SYMBOL_GPL(crypto_attr_alg2);
795  
796  int crypto_attr_u32(struct rtattr *rta, u32 *num)
797  {
798  	struct crypto_attr_u32 *nu32;
799  
800  	if (!rta)
801  		return -ENOENT;
802  	if (RTA_PAYLOAD(rta) < sizeof(*nu32))
803  		return -EINVAL;
804  	if (rta->rta_type != CRYPTOA_U32)
805  		return -EINVAL;
806  
807  	nu32 = RTA_DATA(rta);
808  	*num = nu32->num;
809  
810  	return 0;
811  }
812  EXPORT_SYMBOL_GPL(crypto_attr_u32);
813  
814  void *crypto_alloc_instance2(const char *name, struct crypto_alg *alg,
815  			     unsigned int head)
816  {
817  	struct crypto_instance *inst;
818  	char *p;
819  	int err;
820  
821  	p = kzalloc(head + sizeof(*inst) + sizeof(struct crypto_spawn),
822  		    GFP_KERNEL);
823  	if (!p)
824  		return ERR_PTR(-ENOMEM);
825  
826  	inst = (void *)(p + head);
827  
828  	err = -ENAMETOOLONG;
829  	if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
830  		     alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
831  		goto err_free_inst;
832  
833  	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
834  		     name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
835  		goto err_free_inst;
836  
837  	return p;
838  
839  err_free_inst:
840  	kfree(p);
841  	return ERR_PTR(err);
842  }
843  EXPORT_SYMBOL_GPL(crypto_alloc_instance2);
844  
845  struct crypto_instance *crypto_alloc_instance(const char *name,
846  					      struct crypto_alg *alg)
847  {
848  	struct crypto_instance *inst;
849  	struct crypto_spawn *spawn;
850  	int err;
851  
852  	inst = crypto_alloc_instance2(name, alg, 0);
853  	if (IS_ERR(inst))
854  		goto out;
855  
856  	spawn = crypto_instance_ctx(inst);
857  	err = crypto_init_spawn(spawn, alg, inst,
858  				CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
859  
860  	if (err)
861  		goto err_free_inst;
862  
863  	return inst;
864  
865  err_free_inst:
866  	kfree(inst);
867  	inst = ERR_PTR(err);
868  
869  out:
870  	return inst;
871  }
872  EXPORT_SYMBOL_GPL(crypto_alloc_instance);
873  
874  void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
875  {
876  	INIT_LIST_HEAD(&queue->list);
877  	queue->backlog = &queue->list;
878  	queue->qlen = 0;
879  	queue->max_qlen = max_qlen;
880  }
881  EXPORT_SYMBOL_GPL(crypto_init_queue);
882  
883  int crypto_enqueue_request(struct crypto_queue *queue,
884  			   struct crypto_async_request *request)
885  {
886  	int err = -EINPROGRESS;
887  
888  	if (unlikely(queue->qlen >= queue->max_qlen)) {
889  		err = -EBUSY;
890  		if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG))
891  			goto out;
892  		if (queue->backlog == &queue->list)
893  			queue->backlog = &request->list;
894  	}
895  
896  	queue->qlen++;
897  	list_add_tail(&request->list, &queue->list);
898  
899  out:
900  	return err;
901  }
902  EXPORT_SYMBOL_GPL(crypto_enqueue_request);
903  
904  struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
905  {
906  	struct list_head *request;
907  
908  	if (unlikely(!queue->qlen))
909  		return NULL;
910  
911  	queue->qlen--;
912  
913  	if (queue->backlog != &queue->list)
914  		queue->backlog = queue->backlog->next;
915  
916  	request = queue->list.next;
917  	list_del(request);
918  
919  	return list_entry(request, struct crypto_async_request, list);
920  }
921  EXPORT_SYMBOL_GPL(crypto_dequeue_request);
922  
923  int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm)
924  {
925  	struct crypto_async_request *req;
926  
927  	list_for_each_entry(req, &queue->list, list) {
928  		if (req->tfm == tfm)
929  			return 1;
930  	}
931  
932  	return 0;
933  }
934  EXPORT_SYMBOL_GPL(crypto_tfm_in_queue);
935  
936  static inline void crypto_inc_byte(u8 *a, unsigned int size)
937  {
938  	u8 *b = (a + size);
939  	u8 c;
940  
941  	for (; size; size--) {
942  		c = *--b + 1;
943  		*b = c;
944  		if (c)
945  			break;
946  	}
947  }
948  
949  void crypto_inc(u8 *a, unsigned int size)
950  {
951  	__be32 *b = (__be32 *)(a + size);
952  	u32 c;
953  
954  	for (; size >= 4; size -= 4) {
955  		c = be32_to_cpu(*--b) + 1;
956  		*b = cpu_to_be32(c);
957  		if (c)
958  			return;
959  	}
960  
961  	crypto_inc_byte(a, size);
962  }
963  EXPORT_SYMBOL_GPL(crypto_inc);
964  
965  static inline void crypto_xor_byte(u8 *a, const u8 *b, unsigned int size)
966  {
967  	for (; size; size--)
968  		*a++ ^= *b++;
969  }
970  
971  void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
972  {
973  	u32 *a = (u32 *)dst;
974  	u32 *b = (u32 *)src;
975  
976  	for (; size >= 4; size -= 4)
977  		*a++ ^= *b++;
978  
979  	crypto_xor_byte((u8 *)a, (u8 *)b, size);
980  }
981  EXPORT_SYMBOL_GPL(crypto_xor);
982  
983  unsigned int crypto_alg_extsize(struct crypto_alg *alg)
984  {
985  	return alg->cra_ctxsize +
986  	       (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));
987  }
988  EXPORT_SYMBOL_GPL(crypto_alg_extsize);
989  
990  static int __init crypto_algapi_init(void)
991  {
992  	crypto_init_proc();
993  	return 0;
994  }
995  
996  static void __exit crypto_algapi_exit(void)
997  {
998  	crypto_exit_proc();
999  }
1000  
1001  module_init(crypto_algapi_init);
1002  module_exit(crypto_algapi_exit);
1003  
1004  MODULE_LICENSE("GPL");
1005  MODULE_DESCRIPTION("Cryptographic algorithms API");
1006