Loading...
1/*
2 * Scatterlist Cryptographic API.
3 *
4 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
5 * Copyright (c) 2002 David S. Miller (davem@redhat.com)
6 * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
7 *
8 * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
9 * and Nettle, by Niels Möller.
10 *
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by the Free
13 * Software Foundation; either version 2 of the License, or (at your option)
14 * any later version.
15 *
16 */
17
18#include <linux/err.h>
19#include <linux/errno.h>
20#include <linux/kernel.h>
21#include <linux/kmod.h>
22#include <linux/module.h>
23#include <linux/param.h>
24#include <linux/sched/signal.h>
25#include <linux/slab.h>
26#include <linux/string.h>
27#include <linux/completion.h>
28#include "internal.h"
29
30LIST_HEAD(crypto_alg_list);
31EXPORT_SYMBOL_GPL(crypto_alg_list);
32DECLARE_RWSEM(crypto_alg_sem);
33EXPORT_SYMBOL_GPL(crypto_alg_sem);
34
35BLOCKING_NOTIFIER_HEAD(crypto_chain);
36EXPORT_SYMBOL_GPL(crypto_chain);
37
38static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg);
39
40struct crypto_alg *crypto_mod_get(struct crypto_alg *alg)
41{
42 return try_module_get(alg->cra_module) ? crypto_alg_get(alg) : NULL;
43}
44EXPORT_SYMBOL_GPL(crypto_mod_get);
45
46void crypto_mod_put(struct crypto_alg *alg)
47{
48 struct module *module = alg->cra_module;
49
50 crypto_alg_put(alg);
51 module_put(module);
52}
53EXPORT_SYMBOL_GPL(crypto_mod_put);
54
55static inline int crypto_is_test_larval(struct crypto_larval *larval)
56{
57 return larval->alg.cra_driver_name[0];
58}
59
60static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type,
61 u32 mask)
62{
63 struct crypto_alg *q, *alg = NULL;
64 int best = -2;
65
66 list_for_each_entry(q, &crypto_alg_list, cra_list) {
67 int exact, fuzzy;
68
69 if (crypto_is_moribund(q))
70 continue;
71
72 if ((q->cra_flags ^ type) & mask)
73 continue;
74
75 if (crypto_is_larval(q) &&
76 !crypto_is_test_larval((struct crypto_larval *)q) &&
77 ((struct crypto_larval *)q)->mask != mask)
78 continue;
79
80 exact = !strcmp(q->cra_driver_name, name);
81 fuzzy = !strcmp(q->cra_name, name);
82 if (!exact && !(fuzzy && q->cra_priority > best))
83 continue;
84
85 if (unlikely(!crypto_mod_get(q)))
86 continue;
87
88 best = q->cra_priority;
89 if (alg)
90 crypto_mod_put(alg);
91 alg = q;
92
93 if (exact)
94 break;
95 }
96
97 return alg;
98}
99
100static void crypto_larval_destroy(struct crypto_alg *alg)
101{
102 struct crypto_larval *larval = (void *)alg;
103
104 BUG_ON(!crypto_is_larval(alg));
105 if (larval->adult)
106 crypto_mod_put(larval->adult);
107 kfree(larval);
108}
109
110struct crypto_larval *crypto_larval_alloc(const char *name, u32 type, u32 mask)
111{
112 struct crypto_larval *larval;
113
114 larval = kzalloc(sizeof(*larval), GFP_KERNEL);
115 if (!larval)
116 return ERR_PTR(-ENOMEM);
117
118 larval->mask = mask;
119 larval->alg.cra_flags = CRYPTO_ALG_LARVAL | type;
120 larval->alg.cra_priority = -1;
121 larval->alg.cra_destroy = crypto_larval_destroy;
122
123 strlcpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME);
124 init_completion(&larval->completion);
125
126 return larval;
127}
128EXPORT_SYMBOL_GPL(crypto_larval_alloc);
129
130static struct crypto_alg *crypto_larval_add(const char *name, u32 type,
131 u32 mask)
132{
133 struct crypto_alg *alg;
134 struct crypto_larval *larval;
135
136 larval = crypto_larval_alloc(name, type, mask);
137 if (IS_ERR(larval))
138 return ERR_CAST(larval);
139
140 refcount_set(&larval->alg.cra_refcnt, 2);
141
142 down_write(&crypto_alg_sem);
143 alg = __crypto_alg_lookup(name, type, mask);
144 if (!alg) {
145 alg = &larval->alg;
146 list_add(&alg->cra_list, &crypto_alg_list);
147 }
148 up_write(&crypto_alg_sem);
149
150 if (alg != &larval->alg) {
151 kfree(larval);
152 if (crypto_is_larval(alg))
153 alg = crypto_larval_wait(alg);
154 }
155
156 return alg;
157}
158
159void crypto_larval_kill(struct crypto_alg *alg)
160{
161 struct crypto_larval *larval = (void *)alg;
162
163 down_write(&crypto_alg_sem);
164 list_del(&alg->cra_list);
165 up_write(&crypto_alg_sem);
166 complete_all(&larval->completion);
167 crypto_alg_put(alg);
168}
169EXPORT_SYMBOL_GPL(crypto_larval_kill);
170
171static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg)
172{
173 struct crypto_larval *larval = (void *)alg;
174 long timeout;
175
176 timeout = wait_for_completion_killable_timeout(
177 &larval->completion, 60 * HZ);
178
179 alg = larval->adult;
180 if (timeout < 0)
181 alg = ERR_PTR(-EINTR);
182 else if (!timeout)
183 alg = ERR_PTR(-ETIMEDOUT);
184 else if (!alg)
185 alg = ERR_PTR(-ENOENT);
186 else if (crypto_is_test_larval(larval) &&
187 !(alg->cra_flags & CRYPTO_ALG_TESTED))
188 alg = ERR_PTR(-EAGAIN);
189 else if (!crypto_mod_get(alg))
190 alg = ERR_PTR(-EAGAIN);
191 crypto_mod_put(&larval->alg);
192
193 return alg;
194}
195
196static struct crypto_alg *crypto_alg_lookup(const char *name, u32 type,
197 u32 mask)
198{
199 struct crypto_alg *alg;
200 u32 test = 0;
201
202 if (!((type | mask) & CRYPTO_ALG_TESTED))
203 test |= CRYPTO_ALG_TESTED;
204
205 down_read(&crypto_alg_sem);
206 alg = __crypto_alg_lookup(name, type | test, mask | test);
207 if (!alg && test) {
208 alg = __crypto_alg_lookup(name, type, mask);
209 if (alg && !crypto_is_larval(alg)) {
210 /* Test failed */
211 crypto_mod_put(alg);
212 alg = ERR_PTR(-ELIBBAD);
213 }
214 }
215 up_read(&crypto_alg_sem);
216
217 return alg;
218}
219
220static struct crypto_alg *crypto_larval_lookup(const char *name, u32 type,
221 u32 mask)
222{
223 struct crypto_alg *alg;
224
225 if (!name)
226 return ERR_PTR(-ENOENT);
227
228 type &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
229 mask &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
230
231 alg = crypto_alg_lookup(name, type, mask);
232 if (!alg) {
233 request_module("crypto-%s", name);
234
235 if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask &
236 CRYPTO_ALG_NEED_FALLBACK))
237 request_module("crypto-%s-all", name);
238
239 alg = crypto_alg_lookup(name, type, mask);
240 }
241
242 if (!IS_ERR_OR_NULL(alg) && crypto_is_larval(alg))
243 alg = crypto_larval_wait(alg);
244 else if (!alg)
245 alg = crypto_larval_add(name, type, mask);
246
247 return alg;
248}
249
250int crypto_probing_notify(unsigned long val, void *v)
251{
252 int ok;
253
254 ok = blocking_notifier_call_chain(&crypto_chain, val, v);
255 if (ok == NOTIFY_DONE) {
256 request_module("cryptomgr");
257 ok = blocking_notifier_call_chain(&crypto_chain, val, v);
258 }
259
260 return ok;
261}
262EXPORT_SYMBOL_GPL(crypto_probing_notify);
263
264struct crypto_alg *crypto_alg_mod_lookup(const char *name, u32 type, u32 mask)
265{
266 struct crypto_alg *alg;
267 struct crypto_alg *larval;
268 int ok;
269
270 /*
271 * If the internal flag is set for a cipher, require a caller to
272 * to invoke the cipher with the internal flag to use that cipher.
273 * Also, if a caller wants to allocate a cipher that may or may
274 * not be an internal cipher, use type | CRYPTO_ALG_INTERNAL and
275 * !(mask & CRYPTO_ALG_INTERNAL).
276 */
277 if (!((type | mask) & CRYPTO_ALG_INTERNAL))
278 mask |= CRYPTO_ALG_INTERNAL;
279
280 larval = crypto_larval_lookup(name, type, mask);
281 if (IS_ERR(larval) || !crypto_is_larval(larval))
282 return larval;
283
284 ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);
285
286 if (ok == NOTIFY_STOP)
287 alg = crypto_larval_wait(larval);
288 else {
289 crypto_mod_put(larval);
290 alg = ERR_PTR(-ENOENT);
291 }
292 crypto_larval_kill(larval);
293 return alg;
294}
295EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
296
297static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
298{
299 const struct crypto_type *type_obj = tfm->__crt_alg->cra_type;
300
301 if (type_obj)
302 return type_obj->init(tfm, type, mask);
303
304 switch (crypto_tfm_alg_type(tfm)) {
305 case CRYPTO_ALG_TYPE_CIPHER:
306 return crypto_init_cipher_ops(tfm);
307
308 case CRYPTO_ALG_TYPE_COMPRESS:
309 return crypto_init_compress_ops(tfm);
310
311 default:
312 break;
313 }
314
315 BUG();
316 return -EINVAL;
317}
318
319static void crypto_exit_ops(struct crypto_tfm *tfm)
320{
321 const struct crypto_type *type = tfm->__crt_alg->cra_type;
322
323 if (type && tfm->exit)
324 tfm->exit(tfm);
325}
326
327static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask)
328{
329 const struct crypto_type *type_obj = alg->cra_type;
330 unsigned int len;
331
332 len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1);
333 if (type_obj)
334 return len + type_obj->ctxsize(alg, type, mask);
335
336 switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
337 default:
338 BUG();
339
340 case CRYPTO_ALG_TYPE_CIPHER:
341 len += crypto_cipher_ctxsize(alg);
342 break;
343
344 case CRYPTO_ALG_TYPE_COMPRESS:
345 len += crypto_compress_ctxsize(alg);
346 break;
347 }
348
349 return len;
350}
351
352void crypto_shoot_alg(struct crypto_alg *alg)
353{
354 down_write(&crypto_alg_sem);
355 alg->cra_flags |= CRYPTO_ALG_DYING;
356 up_write(&crypto_alg_sem);
357}
358EXPORT_SYMBOL_GPL(crypto_shoot_alg);
359
360struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type,
361 u32 mask)
362{
363 struct crypto_tfm *tfm = NULL;
364 unsigned int tfm_size;
365 int err = -ENOMEM;
366
367 tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
368 tfm = kzalloc(tfm_size, GFP_KERNEL);
369 if (tfm == NULL)
370 goto out_err;
371
372 tfm->__crt_alg = alg;
373
374 err = crypto_init_ops(tfm, type, mask);
375 if (err)
376 goto out_free_tfm;
377
378 if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
379 goto cra_init_failed;
380
381 goto out;
382
383cra_init_failed:
384 crypto_exit_ops(tfm);
385out_free_tfm:
386 if (err == -EAGAIN)
387 crypto_shoot_alg(alg);
388 kfree(tfm);
389out_err:
390 tfm = ERR_PTR(err);
391out:
392 return tfm;
393}
394EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
395
396/*
397 * crypto_alloc_base - Locate algorithm and allocate transform
398 * @alg_name: Name of algorithm
399 * @type: Type of algorithm
400 * @mask: Mask for type comparison
401 *
402 * This function should not be used by new algorithm types.
403 * Please use crypto_alloc_tfm instead.
404 *
405 * crypto_alloc_base() will first attempt to locate an already loaded
406 * algorithm. If that fails and the kernel supports dynamically loadable
407 * modules, it will then attempt to load a module of the same name or
408 * alias. If that fails it will send a query to any loaded crypto manager
409 * to construct an algorithm on the fly. A refcount is grabbed on the
410 * algorithm which is then associated with the new transform.
411 *
412 * The returned transform is of a non-determinate type. Most people
413 * should use one of the more specific allocation functions such as
414 * crypto_alloc_blkcipher.
415 *
416 * In case of error the return value is an error pointer.
417 */
418struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
419{
420 struct crypto_tfm *tfm;
421 int err;
422
423 for (;;) {
424 struct crypto_alg *alg;
425
426 alg = crypto_alg_mod_lookup(alg_name, type, mask);
427 if (IS_ERR(alg)) {
428 err = PTR_ERR(alg);
429 goto err;
430 }
431
432 tfm = __crypto_alloc_tfm(alg, type, mask);
433 if (!IS_ERR(tfm))
434 return tfm;
435
436 crypto_mod_put(alg);
437 err = PTR_ERR(tfm);
438
439err:
440 if (err != -EAGAIN)
441 break;
442 if (fatal_signal_pending(current)) {
443 err = -EINTR;
444 break;
445 }
446 }
447
448 return ERR_PTR(err);
449}
450EXPORT_SYMBOL_GPL(crypto_alloc_base);
451
452void *crypto_create_tfm(struct crypto_alg *alg,
453 const struct crypto_type *frontend)
454{
455 char *mem;
456 struct crypto_tfm *tfm = NULL;
457 unsigned int tfmsize;
458 unsigned int total;
459 int err = -ENOMEM;
460
461 tfmsize = frontend->tfmsize;
462 total = tfmsize + sizeof(*tfm) + frontend->extsize(alg);
463
464 mem = kzalloc(total, GFP_KERNEL);
465 if (mem == NULL)
466 goto out_err;
467
468 tfm = (struct crypto_tfm *)(mem + tfmsize);
469 tfm->__crt_alg = alg;
470
471 err = frontend->init_tfm(tfm);
472 if (err)
473 goto out_free_tfm;
474
475 if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
476 goto cra_init_failed;
477
478 goto out;
479
480cra_init_failed:
481 crypto_exit_ops(tfm);
482out_free_tfm:
483 if (err == -EAGAIN)
484 crypto_shoot_alg(alg);
485 kfree(mem);
486out_err:
487 mem = ERR_PTR(err);
488out:
489 return mem;
490}
491EXPORT_SYMBOL_GPL(crypto_create_tfm);
492
493struct crypto_alg *crypto_find_alg(const char *alg_name,
494 const struct crypto_type *frontend,
495 u32 type, u32 mask)
496{
497 if (frontend) {
498 type &= frontend->maskclear;
499 mask &= frontend->maskclear;
500 type |= frontend->type;
501 mask |= frontend->maskset;
502 }
503
504 return crypto_alg_mod_lookup(alg_name, type, mask);
505}
506EXPORT_SYMBOL_GPL(crypto_find_alg);
507
508/*
509 * crypto_alloc_tfm - Locate algorithm and allocate transform
510 * @alg_name: Name of algorithm
511 * @frontend: Frontend algorithm type
512 * @type: Type of algorithm
513 * @mask: Mask for type comparison
514 *
515 * crypto_alloc_tfm() will first attempt to locate an already loaded
516 * algorithm. If that fails and the kernel supports dynamically loadable
517 * modules, it will then attempt to load a module of the same name or
518 * alias. If that fails it will send a query to any loaded crypto manager
519 * to construct an algorithm on the fly. A refcount is grabbed on the
520 * algorithm which is then associated with the new transform.
521 *
522 * The returned transform is of a non-determinate type. Most people
523 * should use one of the more specific allocation functions such as
524 * crypto_alloc_blkcipher.
525 *
526 * In case of error the return value is an error pointer.
527 */
528void *crypto_alloc_tfm(const char *alg_name,
529 const struct crypto_type *frontend, u32 type, u32 mask)
530{
531 void *tfm;
532 int err;
533
534 for (;;) {
535 struct crypto_alg *alg;
536
537 alg = crypto_find_alg(alg_name, frontend, type, mask);
538 if (IS_ERR(alg)) {
539 err = PTR_ERR(alg);
540 goto err;
541 }
542
543 tfm = crypto_create_tfm(alg, frontend);
544 if (!IS_ERR(tfm))
545 return tfm;
546
547 crypto_mod_put(alg);
548 err = PTR_ERR(tfm);
549
550err:
551 if (err != -EAGAIN)
552 break;
553 if (fatal_signal_pending(current)) {
554 err = -EINTR;
555 break;
556 }
557 }
558
559 return ERR_PTR(err);
560}
561EXPORT_SYMBOL_GPL(crypto_alloc_tfm);
562
563/*
564 * crypto_destroy_tfm - Free crypto transform
565 * @mem: Start of tfm slab
566 * @tfm: Transform to free
567 *
568 * This function frees up the transform and any associated resources,
569 * then drops the refcount on the associated algorithm.
570 */
571void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm)
572{
573 struct crypto_alg *alg;
574
575 if (unlikely(!mem))
576 return;
577
578 alg = tfm->__crt_alg;
579
580 if (!tfm->exit && alg->cra_exit)
581 alg->cra_exit(tfm);
582 crypto_exit_ops(tfm);
583 crypto_mod_put(alg);
584 kzfree(mem);
585}
586EXPORT_SYMBOL_GPL(crypto_destroy_tfm);
587
588int crypto_has_alg(const char *name, u32 type, u32 mask)
589{
590 int ret = 0;
591 struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
592
593 if (!IS_ERR(alg)) {
594 crypto_mod_put(alg);
595 ret = 1;
596 }
597
598 return ret;
599}
600EXPORT_SYMBOL_GPL(crypto_has_alg);
601
602void crypto_req_done(struct crypto_async_request *req, int err)
603{
604 struct crypto_wait *wait = req->data;
605
606 if (err == -EINPROGRESS)
607 return;
608
609 wait->err = err;
610 complete(&wait->completion);
611}
612EXPORT_SYMBOL_GPL(crypto_req_done);
613
614MODULE_DESCRIPTION("Cryptographic core API");
615MODULE_LICENSE("GPL");
1/*
2 * Scatterlist Cryptographic API.
3 *
4 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
5 * Copyright (c) 2002 David S. Miller (davem@redhat.com)
6 * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
7 *
8 * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
9 * and Nettle, by Niels Möller.
10 *
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by the Free
13 * Software Foundation; either version 2 of the License, or (at your option)
14 * any later version.
15 *
16 */
17
18#include <linux/err.h>
19#include <linux/errno.h>
20#include <linux/kernel.h>
21#include <linux/kmod.h>
22#include <linux/module.h>
23#include <linux/param.h>
24#include <linux/sched.h>
25#include <linux/slab.h>
26#include <linux/string.h>
27#include "internal.h"
28
29LIST_HEAD(crypto_alg_list);
30EXPORT_SYMBOL_GPL(crypto_alg_list);
31DECLARE_RWSEM(crypto_alg_sem);
32EXPORT_SYMBOL_GPL(crypto_alg_sem);
33
34BLOCKING_NOTIFIER_HEAD(crypto_chain);
35EXPORT_SYMBOL_GPL(crypto_chain);
36
37static inline struct crypto_alg *crypto_alg_get(struct crypto_alg *alg)
38{
39 atomic_inc(&alg->cra_refcnt);
40 return alg;
41}
42
43struct crypto_alg *crypto_mod_get(struct crypto_alg *alg)
44{
45 return try_module_get(alg->cra_module) ? crypto_alg_get(alg) : NULL;
46}
47EXPORT_SYMBOL_GPL(crypto_mod_get);
48
49void crypto_mod_put(struct crypto_alg *alg)
50{
51 struct module *module = alg->cra_module;
52
53 crypto_alg_put(alg);
54 module_put(module);
55}
56EXPORT_SYMBOL_GPL(crypto_mod_put);
57
58static inline int crypto_is_test_larval(struct crypto_larval *larval)
59{
60 return larval->alg.cra_driver_name[0];
61}
62
63static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type,
64 u32 mask)
65{
66 struct crypto_alg *q, *alg = NULL;
67 int best = -2;
68
69 list_for_each_entry(q, &crypto_alg_list, cra_list) {
70 int exact, fuzzy;
71
72 if (crypto_is_moribund(q))
73 continue;
74
75 if ((q->cra_flags ^ type) & mask)
76 continue;
77
78 if (crypto_is_larval(q) &&
79 !crypto_is_test_larval((struct crypto_larval *)q) &&
80 ((struct crypto_larval *)q)->mask != mask)
81 continue;
82
83 exact = !strcmp(q->cra_driver_name, name);
84 fuzzy = !strcmp(q->cra_name, name);
85 if (!exact && !(fuzzy && q->cra_priority > best))
86 continue;
87
88 if (unlikely(!crypto_mod_get(q)))
89 continue;
90
91 best = q->cra_priority;
92 if (alg)
93 crypto_mod_put(alg);
94 alg = q;
95
96 if (exact)
97 break;
98 }
99
100 return alg;
101}
102
103static void crypto_larval_destroy(struct crypto_alg *alg)
104{
105 struct crypto_larval *larval = (void *)alg;
106
107 BUG_ON(!crypto_is_larval(alg));
108 if (larval->adult)
109 crypto_mod_put(larval->adult);
110 kfree(larval);
111}
112
113struct crypto_larval *crypto_larval_alloc(const char *name, u32 type, u32 mask)
114{
115 struct crypto_larval *larval;
116
117 larval = kzalloc(sizeof(*larval), GFP_KERNEL);
118 if (!larval)
119 return ERR_PTR(-ENOMEM);
120
121 larval->mask = mask;
122 larval->alg.cra_flags = CRYPTO_ALG_LARVAL | type;
123 larval->alg.cra_priority = -1;
124 larval->alg.cra_destroy = crypto_larval_destroy;
125
126 strlcpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME);
127 init_completion(&larval->completion);
128
129 return larval;
130}
131EXPORT_SYMBOL_GPL(crypto_larval_alloc);
132
133static struct crypto_alg *crypto_larval_add(const char *name, u32 type,
134 u32 mask)
135{
136 struct crypto_alg *alg;
137 struct crypto_larval *larval;
138
139 larval = crypto_larval_alloc(name, type, mask);
140 if (IS_ERR(larval))
141 return ERR_CAST(larval);
142
143 atomic_set(&larval->alg.cra_refcnt, 2);
144
145 down_write(&crypto_alg_sem);
146 alg = __crypto_alg_lookup(name, type, mask);
147 if (!alg) {
148 alg = &larval->alg;
149 list_add(&alg->cra_list, &crypto_alg_list);
150 }
151 up_write(&crypto_alg_sem);
152
153 if (alg != &larval->alg)
154 kfree(larval);
155
156 return alg;
157}
158
159void crypto_larval_kill(struct crypto_alg *alg)
160{
161 struct crypto_larval *larval = (void *)alg;
162
163 down_write(&crypto_alg_sem);
164 list_del(&alg->cra_list);
165 up_write(&crypto_alg_sem);
166 complete_all(&larval->completion);
167 crypto_alg_put(alg);
168}
169EXPORT_SYMBOL_GPL(crypto_larval_kill);
170
171static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg)
172{
173 struct crypto_larval *larval = (void *)alg;
174 long timeout;
175
176 timeout = wait_for_completion_interruptible_timeout(
177 &larval->completion, 60 * HZ);
178
179 alg = larval->adult;
180 if (timeout < 0)
181 alg = ERR_PTR(-EINTR);
182 else if (!timeout)
183 alg = ERR_PTR(-ETIMEDOUT);
184 else if (!alg)
185 alg = ERR_PTR(-ENOENT);
186 else if (crypto_is_test_larval(larval) &&
187 !(alg->cra_flags & CRYPTO_ALG_TESTED))
188 alg = ERR_PTR(-EAGAIN);
189 else if (!crypto_mod_get(alg))
190 alg = ERR_PTR(-EAGAIN);
191 crypto_mod_put(&larval->alg);
192
193 return alg;
194}
195
196struct crypto_alg *crypto_alg_lookup(const char *name, u32 type, u32 mask)
197{
198 struct crypto_alg *alg;
199
200 down_read(&crypto_alg_sem);
201 alg = __crypto_alg_lookup(name, type, mask);
202 up_read(&crypto_alg_sem);
203
204 return alg;
205}
206EXPORT_SYMBOL_GPL(crypto_alg_lookup);
207
208struct crypto_alg *crypto_larval_lookup(const char *name, u32 type, u32 mask)
209{
210 struct crypto_alg *alg;
211
212 if (!name)
213 return ERR_PTR(-ENOENT);
214
215 mask &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
216 type &= mask;
217
218 alg = crypto_alg_lookup(name, type, mask);
219 if (!alg) {
220 request_module("%s", name);
221
222 if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask &
223 CRYPTO_ALG_NEED_FALLBACK))
224 request_module("%s-all", name);
225
226 alg = crypto_alg_lookup(name, type, mask);
227 }
228
229 if (alg)
230 return crypto_is_larval(alg) ? crypto_larval_wait(alg) : alg;
231
232 return crypto_larval_add(name, type, mask);
233}
234EXPORT_SYMBOL_GPL(crypto_larval_lookup);
235
236int crypto_probing_notify(unsigned long val, void *v)
237{
238 int ok;
239
240 ok = blocking_notifier_call_chain(&crypto_chain, val, v);
241 if (ok == NOTIFY_DONE) {
242 request_module("cryptomgr");
243 ok = blocking_notifier_call_chain(&crypto_chain, val, v);
244 }
245
246 return ok;
247}
248EXPORT_SYMBOL_GPL(crypto_probing_notify);
249
250struct crypto_alg *crypto_alg_mod_lookup(const char *name, u32 type, u32 mask)
251{
252 struct crypto_alg *alg;
253 struct crypto_alg *larval;
254 int ok;
255
256 if (!((type | mask) & CRYPTO_ALG_TESTED)) {
257 type |= CRYPTO_ALG_TESTED;
258 mask |= CRYPTO_ALG_TESTED;
259 }
260
261 larval = crypto_larval_lookup(name, type, mask);
262 if (IS_ERR(larval) || !crypto_is_larval(larval))
263 return larval;
264
265 ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);
266
267 if (ok == NOTIFY_STOP)
268 alg = crypto_larval_wait(larval);
269 else {
270 crypto_mod_put(larval);
271 alg = ERR_PTR(-ENOENT);
272 }
273 crypto_larval_kill(larval);
274 return alg;
275}
276EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
277
278static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
279{
280 const struct crypto_type *type_obj = tfm->__crt_alg->cra_type;
281
282 if (type_obj)
283 return type_obj->init(tfm, type, mask);
284
285 switch (crypto_tfm_alg_type(tfm)) {
286 case CRYPTO_ALG_TYPE_CIPHER:
287 return crypto_init_cipher_ops(tfm);
288
289 case CRYPTO_ALG_TYPE_COMPRESS:
290 return crypto_init_compress_ops(tfm);
291
292 default:
293 break;
294 }
295
296 BUG();
297 return -EINVAL;
298}
299
300static void crypto_exit_ops(struct crypto_tfm *tfm)
301{
302 const struct crypto_type *type = tfm->__crt_alg->cra_type;
303
304 if (type) {
305 if (tfm->exit)
306 tfm->exit(tfm);
307 return;
308 }
309
310 switch (crypto_tfm_alg_type(tfm)) {
311 case CRYPTO_ALG_TYPE_CIPHER:
312 crypto_exit_cipher_ops(tfm);
313 break;
314
315 case CRYPTO_ALG_TYPE_COMPRESS:
316 crypto_exit_compress_ops(tfm);
317 break;
318
319 default:
320 BUG();
321 }
322}
323
324static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask)
325{
326 const struct crypto_type *type_obj = alg->cra_type;
327 unsigned int len;
328
329 len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1);
330 if (type_obj)
331 return len + type_obj->ctxsize(alg, type, mask);
332
333 switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
334 default:
335 BUG();
336
337 case CRYPTO_ALG_TYPE_CIPHER:
338 len += crypto_cipher_ctxsize(alg);
339 break;
340
341 case CRYPTO_ALG_TYPE_COMPRESS:
342 len += crypto_compress_ctxsize(alg);
343 break;
344 }
345
346 return len;
347}
348
349void crypto_shoot_alg(struct crypto_alg *alg)
350{
351 down_write(&crypto_alg_sem);
352 alg->cra_flags |= CRYPTO_ALG_DYING;
353 up_write(&crypto_alg_sem);
354}
355EXPORT_SYMBOL_GPL(crypto_shoot_alg);
356
357struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type,
358 u32 mask)
359{
360 struct crypto_tfm *tfm = NULL;
361 unsigned int tfm_size;
362 int err = -ENOMEM;
363
364 tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
365 tfm = kzalloc(tfm_size, GFP_KERNEL);
366 if (tfm == NULL)
367 goto out_err;
368
369 tfm->__crt_alg = alg;
370
371 err = crypto_init_ops(tfm, type, mask);
372 if (err)
373 goto out_free_tfm;
374
375 if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
376 goto cra_init_failed;
377
378 goto out;
379
380cra_init_failed:
381 crypto_exit_ops(tfm);
382out_free_tfm:
383 if (err == -EAGAIN)
384 crypto_shoot_alg(alg);
385 kfree(tfm);
386out_err:
387 tfm = ERR_PTR(err);
388out:
389 return tfm;
390}
391EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
392
393/*
394 * crypto_alloc_base - Locate algorithm and allocate transform
395 * @alg_name: Name of algorithm
396 * @type: Type of algorithm
397 * @mask: Mask for type comparison
398 *
399 * This function should not be used by new algorithm types.
400 * Plesae use crypto_alloc_tfm instead.
401 *
402 * crypto_alloc_base() will first attempt to locate an already loaded
403 * algorithm. If that fails and the kernel supports dynamically loadable
404 * modules, it will then attempt to load a module of the same name or
405 * alias. If that fails it will send a query to any loaded crypto manager
406 * to construct an algorithm on the fly. A refcount is grabbed on the
407 * algorithm which is then associated with the new transform.
408 *
409 * The returned transform is of a non-determinate type. Most people
410 * should use one of the more specific allocation functions such as
411 * crypto_alloc_blkcipher.
412 *
413 * In case of error the return value is an error pointer.
414 */
415struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
416{
417 struct crypto_tfm *tfm;
418 int err;
419
420 for (;;) {
421 struct crypto_alg *alg;
422
423 alg = crypto_alg_mod_lookup(alg_name, type, mask);
424 if (IS_ERR(alg)) {
425 err = PTR_ERR(alg);
426 goto err;
427 }
428
429 tfm = __crypto_alloc_tfm(alg, type, mask);
430 if (!IS_ERR(tfm))
431 return tfm;
432
433 crypto_mod_put(alg);
434 err = PTR_ERR(tfm);
435
436err:
437 if (err != -EAGAIN)
438 break;
439 if (signal_pending(current)) {
440 err = -EINTR;
441 break;
442 }
443 }
444
445 return ERR_PTR(err);
446}
447EXPORT_SYMBOL_GPL(crypto_alloc_base);
448
449void *crypto_create_tfm(struct crypto_alg *alg,
450 const struct crypto_type *frontend)
451{
452 char *mem;
453 struct crypto_tfm *tfm = NULL;
454 unsigned int tfmsize;
455 unsigned int total;
456 int err = -ENOMEM;
457
458 tfmsize = frontend->tfmsize;
459 total = tfmsize + sizeof(*tfm) + frontend->extsize(alg);
460
461 mem = kzalloc(total, GFP_KERNEL);
462 if (mem == NULL)
463 goto out_err;
464
465 tfm = (struct crypto_tfm *)(mem + tfmsize);
466 tfm->__crt_alg = alg;
467
468 err = frontend->init_tfm(tfm);
469 if (err)
470 goto out_free_tfm;
471
472 if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
473 goto cra_init_failed;
474
475 goto out;
476
477cra_init_failed:
478 crypto_exit_ops(tfm);
479out_free_tfm:
480 if (err == -EAGAIN)
481 crypto_shoot_alg(alg);
482 kfree(mem);
483out_err:
484 mem = ERR_PTR(err);
485out:
486 return mem;
487}
488EXPORT_SYMBOL_GPL(crypto_create_tfm);
489
490struct crypto_alg *crypto_find_alg(const char *alg_name,
491 const struct crypto_type *frontend,
492 u32 type, u32 mask)
493{
494 struct crypto_alg *(*lookup)(const char *name, u32 type, u32 mask) =
495 crypto_alg_mod_lookup;
496
497 if (frontend) {
498 type &= frontend->maskclear;
499 mask &= frontend->maskclear;
500 type |= frontend->type;
501 mask |= frontend->maskset;
502
503 if (frontend->lookup)
504 lookup = frontend->lookup;
505 }
506
507 return lookup(alg_name, type, mask);
508}
509EXPORT_SYMBOL_GPL(crypto_find_alg);
510
511/*
512 * crypto_alloc_tfm - Locate algorithm and allocate transform
513 * @alg_name: Name of algorithm
514 * @frontend: Frontend algorithm type
515 * @type: Type of algorithm
516 * @mask: Mask for type comparison
517 *
518 * crypto_alloc_tfm() will first attempt to locate an already loaded
519 * algorithm. If that fails and the kernel supports dynamically loadable
520 * modules, it will then attempt to load a module of the same name or
521 * alias. If that fails it will send a query to any loaded crypto manager
522 * to construct an algorithm on the fly. A refcount is grabbed on the
523 * algorithm which is then associated with the new transform.
524 *
525 * The returned transform is of a non-determinate type. Most people
526 * should use one of the more specific allocation functions such as
527 * crypto_alloc_blkcipher.
528 *
529 * In case of error the return value is an error pointer.
530 */
531void *crypto_alloc_tfm(const char *alg_name,
532 const struct crypto_type *frontend, u32 type, u32 mask)
533{
534 void *tfm;
535 int err;
536
537 for (;;) {
538 struct crypto_alg *alg;
539
540 alg = crypto_find_alg(alg_name, frontend, type, mask);
541 if (IS_ERR(alg)) {
542 err = PTR_ERR(alg);
543 goto err;
544 }
545
546 tfm = crypto_create_tfm(alg, frontend);
547 if (!IS_ERR(tfm))
548 return tfm;
549
550 crypto_mod_put(alg);
551 err = PTR_ERR(tfm);
552
553err:
554 if (err != -EAGAIN)
555 break;
556 if (signal_pending(current)) {
557 err = -EINTR;
558 break;
559 }
560 }
561
562 return ERR_PTR(err);
563}
564EXPORT_SYMBOL_GPL(crypto_alloc_tfm);
565
566/*
567 * crypto_destroy_tfm - Free crypto transform
568 * @mem: Start of tfm slab
569 * @tfm: Transform to free
570 *
571 * This function frees up the transform and any associated resources,
572 * then drops the refcount on the associated algorithm.
573 */
574void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm)
575{
576 struct crypto_alg *alg;
577
578 if (unlikely(!mem))
579 return;
580
581 alg = tfm->__crt_alg;
582
583 if (!tfm->exit && alg->cra_exit)
584 alg->cra_exit(tfm);
585 crypto_exit_ops(tfm);
586 crypto_mod_put(alg);
587 kzfree(mem);
588}
589EXPORT_SYMBOL_GPL(crypto_destroy_tfm);
590
591int crypto_has_alg(const char *name, u32 type, u32 mask)
592{
593 int ret = 0;
594 struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
595
596 if (!IS_ERR(alg)) {
597 crypto_mod_put(alg);
598 ret = 1;
599 }
600
601 return ret;
602}
603EXPORT_SYMBOL_GPL(crypto_has_alg);
604
605MODULE_DESCRIPTION("Cryptographic core API");
606MODULE_LICENSE("GPL");