Commit | Line | Data |
---|---|---|
cce9e06d HX |
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 | ||
6bfd4809 | 13 | #include <linux/err.h> |
cce9e06d HX |
14 | #include <linux/errno.h> |
15 | #include <linux/init.h> | |
16 | #include <linux/kernel.h> | |
4cc7720c | 17 | #include <linux/list.h> |
cce9e06d | 18 | #include <linux/module.h> |
7fed0bf2 | 19 | #include <linux/rtnetlink.h> |
cce9e06d HX |
20 | #include <linux/string.h> |
21 | ||
22 | #include "internal.h" | |
23 | ||
4cc7720c HX |
24 | static LIST_HEAD(crypto_template_list); |
25 | ||
492e2b63 | 26 | void crypto_larval_error(const char *name, u32 type, u32 mask) |
2825982d HX |
27 | { |
28 | struct crypto_alg *alg; | |
29 | ||
30 | down_read(&crypto_alg_sem); | |
492e2b63 | 31 | alg = __crypto_alg_lookup(name, type, mask); |
2825982d HX |
32 | up_read(&crypto_alg_sem); |
33 | ||
34 | if (alg) { | |
35 | if (crypto_is_larval(alg)) { | |
36 | struct crypto_larval *larval = (void *)alg; | |
37 | complete(&larval->completion); | |
38 | } | |
39 | crypto_mod_put(alg); | |
40 | } | |
41 | } | |
42 | EXPORT_SYMBOL_GPL(crypto_larval_error); | |
43 | ||
cce9e06d HX |
44 | static inline int crypto_set_driver_name(struct crypto_alg *alg) |
45 | { | |
46 | static const char suffix[] = "-generic"; | |
47 | char *driver_name = alg->cra_driver_name; | |
48 | int len; | |
49 | ||
50 | if (*driver_name) | |
51 | return 0; | |
52 | ||
53 | len = strlcpy(driver_name, alg->cra_name, CRYPTO_MAX_ALG_NAME); | |
54 | if (len + sizeof(suffix) > CRYPTO_MAX_ALG_NAME) | |
55 | return -ENAMETOOLONG; | |
56 | ||
57 | memcpy(driver_name + len, suffix, sizeof(suffix)); | |
58 | return 0; | |
59 | } | |
60 | ||
4cc7720c | 61 | static int crypto_check_alg(struct crypto_alg *alg) |
cce9e06d | 62 | { |
cce9e06d HX |
63 | if (alg->cra_alignmask & (alg->cra_alignmask + 1)) |
64 | return -EINVAL; | |
65 | ||
66 | if (alg->cra_alignmask & alg->cra_blocksize) | |
67 | return -EINVAL; | |
68 | ||
69 | if (alg->cra_blocksize > PAGE_SIZE / 8) | |
70 | return -EINVAL; | |
71 | ||
72 | if (alg->cra_priority < 0) | |
73 | return -EINVAL; | |
cce9e06d | 74 | |
4cc7720c HX |
75 | return crypto_set_driver_name(alg); |
76 | } | |
77 | ||
6bfd4809 HX |
78 | static void crypto_destroy_instance(struct crypto_alg *alg) |
79 | { | |
80 | struct crypto_instance *inst = (void *)alg; | |
81 | struct crypto_template *tmpl = inst->tmpl; | |
82 | ||
83 | tmpl->free(inst); | |
84 | crypto_tmpl_put(tmpl); | |
85 | } | |
86 | ||
87 | static void crypto_remove_spawns(struct list_head *spawns, | |
88 | struct list_head *list) | |
89 | { | |
90 | struct crypto_spawn *spawn, *n; | |
91 | ||
92 | list_for_each_entry_safe(spawn, n, spawns, list) { | |
93 | struct crypto_instance *inst = spawn->inst; | |
94 | struct crypto_template *tmpl = inst->tmpl; | |
95 | ||
96 | list_del_init(&spawn->list); | |
97 | spawn->alg = NULL; | |
98 | ||
99 | if (crypto_is_dead(&inst->alg)) | |
100 | continue; | |
101 | ||
102 | inst->alg.cra_flags |= CRYPTO_ALG_DEAD; | |
103 | if (!tmpl || !crypto_tmpl_get(tmpl)) | |
104 | continue; | |
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 | if (!list_empty(&inst->alg.cra_users)) { | |
112 | if (&n->list == spawns) | |
113 | n = list_entry(inst->alg.cra_users.next, | |
114 | typeof(*n), list); | |
115 | __list_splice(&inst->alg.cra_users, spawns->prev); | |
116 | } | |
117 | } | |
118 | } | |
119 | ||
120 | static int __crypto_register_alg(struct crypto_alg *alg, | |
121 | struct list_head *list) | |
4cc7720c HX |
122 | { |
123 | struct crypto_alg *q; | |
6bfd4809 HX |
124 | int ret = -EAGAIN; |
125 | ||
126 | if (crypto_is_dead(alg)) | |
127 | goto out; | |
128 | ||
129 | INIT_LIST_HEAD(&alg->cra_users); | |
130 | ||
131 | ret = -EEXIST; | |
4cc7720c | 132 | |
2825982d | 133 | atomic_set(&alg->cra_refcnt, 1); |
cce9e06d | 134 | list_for_each_entry(q, &crypto_alg_list, cra_list) { |
4cc7720c | 135 | if (q == alg) |
cce9e06d | 136 | goto out; |
6bfd4809 HX |
137 | |
138 | if (crypto_is_moribund(q)) | |
139 | continue; | |
140 | ||
141 | if (crypto_is_larval(q)) { | |
2825982d HX |
142 | struct crypto_larval *larval = (void *)q; |
143 | ||
6bfd4809 HX |
144 | if (strcmp(alg->cra_name, q->cra_name) && |
145 | strcmp(alg->cra_driver_name, q->cra_name)) | |
146 | continue; | |
147 | ||
148 | if (larval->adult) | |
149 | continue; | |
492e2b63 HX |
150 | if ((q->cra_flags ^ alg->cra_flags) & larval->mask) |
151 | continue; | |
2825982d HX |
152 | if (!crypto_mod_get(alg)) |
153 | continue; | |
6bfd4809 | 154 | |
2825982d HX |
155 | larval->adult = alg; |
156 | complete(&larval->completion); | |
6bfd4809 | 157 | continue; |
2825982d | 158 | } |
6bfd4809 HX |
159 | |
160 | if (strcmp(alg->cra_name, q->cra_name)) | |
161 | continue; | |
162 | ||
163 | if (strcmp(alg->cra_driver_name, q->cra_driver_name) && | |
164 | q->cra_priority > alg->cra_priority) | |
165 | continue; | |
166 | ||
167 | crypto_remove_spawns(&q->cra_users, list); | |
cce9e06d HX |
168 | } |
169 | ||
170 | list_add(&alg->cra_list, &crypto_alg_list); | |
2825982d HX |
171 | |
172 | crypto_notify(CRYPTO_MSG_ALG_REGISTER, alg); | |
4cc7720c | 173 | ret = 0; |
2825982d | 174 | |
cce9e06d | 175 | out: |
cce9e06d HX |
176 | return ret; |
177 | } | |
4cc7720c | 178 | |
6bfd4809 HX |
179 | static void crypto_remove_final(struct list_head *list) |
180 | { | |
181 | struct crypto_alg *alg; | |
182 | struct crypto_alg *n; | |
183 | ||
184 | list_for_each_entry_safe(alg, n, list, cra_list) { | |
185 | list_del_init(&alg->cra_list); | |
186 | crypto_alg_put(alg); | |
187 | } | |
188 | } | |
189 | ||
4cc7720c HX |
190 | int crypto_register_alg(struct crypto_alg *alg) |
191 | { | |
6bfd4809 | 192 | LIST_HEAD(list); |
4cc7720c HX |
193 | int err; |
194 | ||
195 | err = crypto_check_alg(alg); | |
196 | if (err) | |
197 | return err; | |
198 | ||
199 | down_write(&crypto_alg_sem); | |
6bfd4809 | 200 | err = __crypto_register_alg(alg, &list); |
4cc7720c HX |
201 | up_write(&crypto_alg_sem); |
202 | ||
6bfd4809 | 203 | crypto_remove_final(&list); |
4cc7720c HX |
204 | return err; |
205 | } | |
cce9e06d HX |
206 | EXPORT_SYMBOL_GPL(crypto_register_alg); |
207 | ||
6bfd4809 HX |
208 | static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list) |
209 | { | |
210 | if (unlikely(list_empty(&alg->cra_list))) | |
211 | return -ENOENT; | |
212 | ||
213 | alg->cra_flags |= CRYPTO_ALG_DEAD; | |
214 | ||
215 | crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, alg); | |
216 | list_del_init(&alg->cra_list); | |
217 | crypto_remove_spawns(&alg->cra_users, list); | |
218 | ||
219 | return 0; | |
220 | } | |
221 | ||
cce9e06d HX |
222 | int crypto_unregister_alg(struct crypto_alg *alg) |
223 | { | |
6bfd4809 HX |
224 | int ret; |
225 | LIST_HEAD(list); | |
cce9e06d HX |
226 | |
227 | down_write(&crypto_alg_sem); | |
6bfd4809 | 228 | ret = crypto_remove_alg(alg, &list); |
cce9e06d HX |
229 | up_write(&crypto_alg_sem); |
230 | ||
231 | if (ret) | |
232 | return ret; | |
233 | ||
234 | BUG_ON(atomic_read(&alg->cra_refcnt) != 1); | |
235 | if (alg->cra_destroy) | |
236 | alg->cra_destroy(alg); | |
237 | ||
6bfd4809 | 238 | crypto_remove_final(&list); |
cce9e06d HX |
239 | return 0; |
240 | } | |
241 | EXPORT_SYMBOL_GPL(crypto_unregister_alg); | |
242 | ||
4cc7720c HX |
243 | int crypto_register_template(struct crypto_template *tmpl) |
244 | { | |
245 | struct crypto_template *q; | |
246 | int err = -EEXIST; | |
247 | ||
248 | down_write(&crypto_alg_sem); | |
249 | ||
250 | list_for_each_entry(q, &crypto_template_list, list) { | |
251 | if (q == tmpl) | |
252 | goto out; | |
253 | } | |
254 | ||
255 | list_add(&tmpl->list, &crypto_template_list); | |
2825982d | 256 | crypto_notify(CRYPTO_MSG_TMPL_REGISTER, tmpl); |
4cc7720c HX |
257 | err = 0; |
258 | out: | |
259 | up_write(&crypto_alg_sem); | |
260 | return err; | |
261 | } | |
262 | EXPORT_SYMBOL_GPL(crypto_register_template); | |
263 | ||
264 | void crypto_unregister_template(struct crypto_template *tmpl) | |
265 | { | |
266 | struct crypto_instance *inst; | |
267 | struct hlist_node *p, *n; | |
268 | struct hlist_head *list; | |
6bfd4809 | 269 | LIST_HEAD(users); |
4cc7720c HX |
270 | |
271 | down_write(&crypto_alg_sem); | |
272 | ||
273 | BUG_ON(list_empty(&tmpl->list)); | |
274 | list_del_init(&tmpl->list); | |
275 | ||
276 | list = &tmpl->instances; | |
277 | hlist_for_each_entry(inst, p, list, list) { | |
6bfd4809 HX |
278 | int err = crypto_remove_alg(&inst->alg, &users); |
279 | BUG_ON(err); | |
4cc7720c HX |
280 | } |
281 | ||
2825982d HX |
282 | crypto_notify(CRYPTO_MSG_TMPL_UNREGISTER, tmpl); |
283 | ||
4cc7720c HX |
284 | up_write(&crypto_alg_sem); |
285 | ||
286 | hlist_for_each_entry_safe(inst, p, n, list, list) { | |
287 | BUG_ON(atomic_read(&inst->alg.cra_refcnt) != 1); | |
288 | tmpl->free(inst); | |
289 | } | |
6bfd4809 | 290 | crypto_remove_final(&users); |
4cc7720c HX |
291 | } |
292 | EXPORT_SYMBOL_GPL(crypto_unregister_template); | |
293 | ||
294 | static struct crypto_template *__crypto_lookup_template(const char *name) | |
295 | { | |
296 | struct crypto_template *q, *tmpl = NULL; | |
297 | ||
298 | down_read(&crypto_alg_sem); | |
299 | list_for_each_entry(q, &crypto_template_list, list) { | |
300 | if (strcmp(q->name, name)) | |
301 | continue; | |
302 | if (unlikely(!crypto_tmpl_get(q))) | |
303 | continue; | |
304 | ||
305 | tmpl = q; | |
306 | break; | |
307 | } | |
308 | up_read(&crypto_alg_sem); | |
309 | ||
310 | return tmpl; | |
311 | } | |
312 | ||
313 | struct crypto_template *crypto_lookup_template(const char *name) | |
314 | { | |
315 | return try_then_request_module(__crypto_lookup_template(name), name); | |
316 | } | |
317 | EXPORT_SYMBOL_GPL(crypto_lookup_template); | |
318 | ||
319 | int crypto_register_instance(struct crypto_template *tmpl, | |
320 | struct crypto_instance *inst) | |
321 | { | |
6bfd4809 | 322 | LIST_HEAD(list); |
4cc7720c HX |
323 | int err = -EINVAL; |
324 | ||
325 | if (inst->alg.cra_destroy) | |
326 | goto err; | |
327 | ||
328 | err = crypto_check_alg(&inst->alg); | |
329 | if (err) | |
330 | goto err; | |
331 | ||
332 | inst->alg.cra_module = tmpl->module; | |
333 | ||
334 | down_write(&crypto_alg_sem); | |
335 | ||
6bfd4809 | 336 | err = __crypto_register_alg(&inst->alg, &list); |
4cc7720c HX |
337 | if (err) |
338 | goto unlock; | |
339 | ||
340 | hlist_add_head(&inst->list, &tmpl->instances); | |
341 | inst->tmpl = tmpl; | |
342 | ||
343 | unlock: | |
344 | up_write(&crypto_alg_sem); | |
345 | ||
6bfd4809 HX |
346 | crypto_remove_final(&list); |
347 | ||
4cc7720c HX |
348 | err: |
349 | return err; | |
350 | } | |
351 | EXPORT_SYMBOL_GPL(crypto_register_instance); | |
352 | ||
6bfd4809 HX |
353 | int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg, |
354 | struct crypto_instance *inst) | |
355 | { | |
356 | int err = -EAGAIN; | |
357 | ||
358 | spawn->inst = inst; | |
359 | ||
360 | down_write(&crypto_alg_sem); | |
361 | if (!crypto_is_moribund(alg)) { | |
362 | list_add(&spawn->list, &alg->cra_users); | |
363 | spawn->alg = alg; | |
364 | err = 0; | |
365 | } | |
366 | up_write(&crypto_alg_sem); | |
367 | ||
368 | return err; | |
369 | } | |
370 | EXPORT_SYMBOL_GPL(crypto_init_spawn); | |
371 | ||
372 | void crypto_drop_spawn(struct crypto_spawn *spawn) | |
373 | { | |
374 | down_write(&crypto_alg_sem); | |
375 | list_del(&spawn->list); | |
376 | up_write(&crypto_alg_sem); | |
377 | } | |
378 | EXPORT_SYMBOL_GPL(crypto_drop_spawn); | |
379 | ||
380 | struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn) | |
381 | { | |
382 | struct crypto_alg *alg; | |
383 | struct crypto_alg *alg2; | |
384 | struct crypto_tfm *tfm; | |
385 | ||
386 | down_read(&crypto_alg_sem); | |
387 | alg = spawn->alg; | |
388 | alg2 = alg; | |
389 | if (alg2) | |
390 | alg2 = crypto_mod_get(alg2); | |
391 | up_read(&crypto_alg_sem); | |
392 | ||
393 | if (!alg2) { | |
394 | if (alg) | |
395 | crypto_shoot_alg(alg); | |
396 | return ERR_PTR(-EAGAIN); | |
397 | } | |
398 | ||
399 | tfm = __crypto_alloc_tfm(alg, 0); | |
400 | if (IS_ERR(tfm)) | |
401 | crypto_mod_put(alg); | |
402 | ||
403 | return tfm; | |
404 | } | |
405 | EXPORT_SYMBOL_GPL(crypto_spawn_tfm); | |
406 | ||
2825982d HX |
407 | int crypto_register_notifier(struct notifier_block *nb) |
408 | { | |
409 | return blocking_notifier_chain_register(&crypto_chain, nb); | |
410 | } | |
411 | EXPORT_SYMBOL_GPL(crypto_register_notifier); | |
412 | ||
413 | int crypto_unregister_notifier(struct notifier_block *nb) | |
414 | { | |
415 | return blocking_notifier_chain_unregister(&crypto_chain, nb); | |
416 | } | |
417 | EXPORT_SYMBOL_GPL(crypto_unregister_notifier); | |
418 | ||
7fed0bf2 HX |
419 | struct crypto_alg *crypto_get_attr_alg(void *param, unsigned int len, |
420 | u32 type, u32 mask) | |
421 | { | |
422 | struct rtattr *rta = param; | |
423 | struct crypto_attr_alg *alga; | |
424 | ||
425 | if (!RTA_OK(rta, len)) | |
426 | return ERR_PTR(-EBADR); | |
427 | if (rta->rta_type != CRYPTOA_ALG || RTA_PAYLOAD(rta) < sizeof(*alga)) | |
428 | return ERR_PTR(-EINVAL); | |
429 | ||
430 | alga = RTA_DATA(rta); | |
431 | alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0; | |
432 | ||
433 | return crypto_alg_mod_lookup(alga->name, type, mask); | |
434 | } | |
435 | EXPORT_SYMBOL_GPL(crypto_get_attr_alg); | |
436 | ||
437 | struct crypto_instance *crypto_alloc_instance(const char *name, | |
438 | struct crypto_alg *alg) | |
439 | { | |
440 | struct crypto_instance *inst; | |
441 | struct crypto_spawn *spawn; | |
442 | int err; | |
443 | ||
444 | inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); | |
445 | if (!inst) | |
446 | return ERR_PTR(-ENOMEM); | |
447 | ||
448 | err = -ENAMETOOLONG; | |
449 | if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name, | |
450 | alg->cra_name) >= CRYPTO_MAX_ALG_NAME) | |
451 | goto err_free_inst; | |
452 | ||
453 | if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", | |
454 | name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME) | |
455 | goto err_free_inst; | |
456 | ||
457 | spawn = crypto_instance_ctx(inst); | |
458 | err = crypto_init_spawn(spawn, alg, inst); | |
459 | ||
460 | if (err) | |
461 | goto err_free_inst; | |
462 | ||
463 | return inst; | |
464 | ||
465 | err_free_inst: | |
466 | kfree(inst); | |
467 | return ERR_PTR(err); | |
468 | } | |
469 | EXPORT_SYMBOL_GPL(crypto_alloc_instance); | |
470 | ||
cce9e06d HX |
471 | static int __init crypto_algapi_init(void) |
472 | { | |
473 | crypto_init_proc(); | |
474 | return 0; | |
475 | } | |
476 | ||
477 | static void __exit crypto_algapi_exit(void) | |
478 | { | |
479 | crypto_exit_proc(); | |
480 | } | |
481 | ||
482 | module_init(crypto_algapi_init); | |
483 | module_exit(crypto_algapi_exit); | |
484 | ||
485 | MODULE_LICENSE("GPL"); | |
486 | MODULE_DESCRIPTION("Cryptographic algorithms API"); |