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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 struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg);
38
39struct crypto_alg *crypto_mod_get(struct crypto_alg *alg)
40{
41 return try_module_get(alg->cra_module) ? crypto_alg_get(alg) : NULL;
42}
43EXPORT_SYMBOL_GPL(crypto_mod_get);
44
45void crypto_mod_put(struct crypto_alg *alg)
46{
47 struct module *module = alg->cra_module;
48
49 crypto_alg_put(alg);
50 module_put(module);
51}
52EXPORT_SYMBOL_GPL(crypto_mod_put);
53
54static inline int crypto_is_test_larval(struct crypto_larval *larval)
55{
56 return larval->alg.cra_driver_name[0];
57}
58
59static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type,
60 u32 mask)
61{
62 struct crypto_alg *q, *alg = NULL;
63 int best = -2;
64
65 list_for_each_entry(q, &crypto_alg_list, cra_list) {
66 int exact, fuzzy;
67
68 if (crypto_is_moribund(q))
69 continue;
70
71 if ((q->cra_flags ^ type) & mask)
72 continue;
73
74 if (crypto_is_larval(q) &&
75 !crypto_is_test_larval((struct crypto_larval *)q) &&
76 ((struct crypto_larval *)q)->mask != mask)
77 continue;
78
79 exact = !strcmp(q->cra_driver_name, name);
80 fuzzy = !strcmp(q->cra_name, name);
81 if (!exact && !(fuzzy && q->cra_priority > best))
82 continue;
83
84 if (unlikely(!crypto_mod_get(q)))
85 continue;
86
87 best = q->cra_priority;
88 if (alg)
89 crypto_mod_put(alg);
90 alg = q;
91
92 if (exact)
93 break;
94 }
95
96 return alg;
97}
98
99static void crypto_larval_destroy(struct crypto_alg *alg)
100{
101 struct crypto_larval *larval = (void *)alg;
102
103 BUG_ON(!crypto_is_larval(alg));
104 if (larval->adult)
105 crypto_mod_put(larval->adult);
106 kfree(larval);
107}
108
109struct crypto_larval *crypto_larval_alloc(const char *name, u32 type, u32 mask)
110{
111 struct crypto_larval *larval;
112
113 larval = kzalloc(sizeof(*larval), GFP_KERNEL);
114 if (!larval)
115 return ERR_PTR(-ENOMEM);
116
117 larval->mask = mask;
118 larval->alg.cra_flags = CRYPTO_ALG_LARVAL | type;
119 larval->alg.cra_priority = -1;
120 larval->alg.cra_destroy = crypto_larval_destroy;
121
122 strlcpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME);
123 init_completion(&larval->completion);
124
125 return larval;
126}
127EXPORT_SYMBOL_GPL(crypto_larval_alloc);
128
129static struct crypto_alg *crypto_larval_add(const char *name, u32 type,
130 u32 mask)
131{
132 struct crypto_alg *alg;
133 struct crypto_larval *larval;
134
135 larval = crypto_larval_alloc(name, type, mask);
136 if (IS_ERR(larval))
137 return ERR_CAST(larval);
138
139 atomic_set(&larval->alg.cra_refcnt, 2);
140
141 down_write(&crypto_alg_sem);
142 alg = __crypto_alg_lookup(name, type, mask);
143 if (!alg) {
144 alg = &larval->alg;
145 list_add(&alg->cra_list, &crypto_alg_list);
146 }
147 up_write(&crypto_alg_sem);
148
149 if (alg != &larval->alg) {
150 kfree(larval);
151 if (crypto_is_larval(alg))
152 alg = crypto_larval_wait(alg);
153 }
154
155 return alg;
156}
157
158void crypto_larval_kill(struct crypto_alg *alg)
159{
160 struct crypto_larval *larval = (void *)alg;
161
162 down_write(&crypto_alg_sem);
163 list_del(&alg->cra_list);
164 up_write(&crypto_alg_sem);
165 complete_all(&larval->completion);
166 crypto_alg_put(alg);
167}
168EXPORT_SYMBOL_GPL(crypto_larval_kill);
169
170static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg)
171{
172 struct crypto_larval *larval = (void *)alg;
173 long timeout;
174
175 timeout = wait_for_completion_killable_timeout(
176 &larval->completion, 60 * HZ);
177
178 alg = larval->adult;
179 if (timeout < 0)
180 alg = ERR_PTR(-EINTR);
181 else if (!timeout)
182 alg = ERR_PTR(-ETIMEDOUT);
183 else if (!alg)
184 alg = ERR_PTR(-ENOENT);
185 else if (crypto_is_test_larval(larval) &&
186 !(alg->cra_flags & CRYPTO_ALG_TESTED))
187 alg = ERR_PTR(-EAGAIN);
188 else if (!crypto_mod_get(alg))
189 alg = ERR_PTR(-EAGAIN);
190 crypto_mod_put(&larval->alg);
191
192 return alg;
193}
194
195struct crypto_alg *crypto_alg_lookup(const char *name, u32 type, u32 mask)
196{
197 struct crypto_alg *alg;
198
199 down_read(&crypto_alg_sem);
200 alg = __crypto_alg_lookup(name, type, mask);
201 up_read(&crypto_alg_sem);
202
203 return alg;
204}
205EXPORT_SYMBOL_GPL(crypto_alg_lookup);
206
207struct crypto_alg *crypto_larval_lookup(const char *name, u32 type, u32 mask)
208{
209 struct crypto_alg *alg;
210
211 if (!name)
212 return ERR_PTR(-ENOENT);
213
214 mask &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
215 type &= mask;
216
217 alg = crypto_alg_lookup(name, type, mask);
218 if (!alg) {
219 request_module("crypto-%s", name);
220
221 if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask &
222 CRYPTO_ALG_NEED_FALLBACK))
223 request_module("crypto-%s-all", name);
224
225 alg = crypto_alg_lookup(name, type, mask);
226 }
227
228 if (alg)
229 return crypto_is_larval(alg) ? crypto_larval_wait(alg) : alg;
230
231 return crypto_larval_add(name, type, mask);
232}
233EXPORT_SYMBOL_GPL(crypto_larval_lookup);
234
235int crypto_probing_notify(unsigned long val, void *v)
236{
237 int ok;
238
239 ok = blocking_notifier_call_chain(&crypto_chain, val, v);
240 if (ok == NOTIFY_DONE) {
241 request_module("cryptomgr");
242 ok = blocking_notifier_call_chain(&crypto_chain, val, v);
243 }
244
245 return ok;
246}
247EXPORT_SYMBOL_GPL(crypto_probing_notify);
248
249struct crypto_alg *crypto_alg_mod_lookup(const char *name, u32 type, u32 mask)
250{
251 struct crypto_alg *alg;
252 struct crypto_alg *larval;
253 int ok;
254
255 if (!((type | mask) & CRYPTO_ALG_TESTED)) {
256 type |= CRYPTO_ALG_TESTED;
257 mask |= CRYPTO_ALG_TESTED;
258 }
259
260 /*
261 * If the internal flag is set for a cipher, require a caller to
262 * to invoke the cipher with the internal flag to use that cipher.
263 * Also, if a caller wants to allocate a cipher that may or may
264 * not be an internal cipher, use type | CRYPTO_ALG_INTERNAL and
265 * !(mask & CRYPTO_ALG_INTERNAL).
266 */
267 if (!((type | mask) & CRYPTO_ALG_INTERNAL))
268 mask |= CRYPTO_ALG_INTERNAL;
269
270 larval = crypto_larval_lookup(name, type, mask);
271 if (IS_ERR(larval) || !crypto_is_larval(larval))
272 return larval;
273
274 ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);
275
276 if (ok == NOTIFY_STOP)
277 alg = crypto_larval_wait(larval);
278 else {
279 crypto_mod_put(larval);
280 alg = ERR_PTR(-ENOENT);
281 }
282 crypto_larval_kill(larval);
283 return alg;
284}
285EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
286
287static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
288{
289 const struct crypto_type *type_obj = tfm->__crt_alg->cra_type;
290
291 if (type_obj)
292 return type_obj->init(tfm, type, mask);
293
294 switch (crypto_tfm_alg_type(tfm)) {
295 case CRYPTO_ALG_TYPE_CIPHER:
296 return crypto_init_cipher_ops(tfm);
297
298 case CRYPTO_ALG_TYPE_COMPRESS:
299 return crypto_init_compress_ops(tfm);
300
301 default:
302 break;
303 }
304
305 BUG();
306 return -EINVAL;
307}
308
309static void crypto_exit_ops(struct crypto_tfm *tfm)
310{
311 const struct crypto_type *type = tfm->__crt_alg->cra_type;
312
313 if (type) {
314 if (tfm->exit)
315 tfm->exit(tfm);
316 return;
317 }
318
319 switch (crypto_tfm_alg_type(tfm)) {
320 case CRYPTO_ALG_TYPE_CIPHER:
321 crypto_exit_cipher_ops(tfm);
322 break;
323
324 case CRYPTO_ALG_TYPE_COMPRESS:
325 crypto_exit_compress_ops(tfm);
326 break;
327
328 default:
329 BUG();
330 }
331}
332
333static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask)
334{
335 const struct crypto_type *type_obj = alg->cra_type;
336 unsigned int len;
337
338 len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1);
339 if (type_obj)
340 return len + type_obj->ctxsize(alg, type, mask);
341
342 switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
343 default:
344 BUG();
345
346 case CRYPTO_ALG_TYPE_CIPHER:
347 len += crypto_cipher_ctxsize(alg);
348 break;
349
350 case CRYPTO_ALG_TYPE_COMPRESS:
351 len += crypto_compress_ctxsize(alg);
352 break;
353 }
354
355 return len;
356}
357
358void crypto_shoot_alg(struct crypto_alg *alg)
359{
360 down_write(&crypto_alg_sem);
361 alg->cra_flags |= CRYPTO_ALG_DYING;
362 up_write(&crypto_alg_sem);
363}
364EXPORT_SYMBOL_GPL(crypto_shoot_alg);
365
366struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type,
367 u32 mask)
368{
369 struct crypto_tfm *tfm = NULL;
370 unsigned int tfm_size;
371 int err = -ENOMEM;
372
373 tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
374 tfm = kzalloc(tfm_size, GFP_KERNEL);
375 if (tfm == NULL)
376 goto out_err;
377
378 tfm->__crt_alg = alg;
379
380 err = crypto_init_ops(tfm, type, mask);
381 if (err)
382 goto out_free_tfm;
383
384 if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
385 goto cra_init_failed;
386
387 goto out;
388
389cra_init_failed:
390 crypto_exit_ops(tfm);
391out_free_tfm:
392 if (err == -EAGAIN)
393 crypto_shoot_alg(alg);
394 kfree(tfm);
395out_err:
396 tfm = ERR_PTR(err);
397out:
398 return tfm;
399}
400EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
401
402/*
403 * crypto_alloc_base - Locate algorithm and allocate transform
404 * @alg_name: Name of algorithm
405 * @type: Type of algorithm
406 * @mask: Mask for type comparison
407 *
408 * This function should not be used by new algorithm types.
409 * Please use crypto_alloc_tfm instead.
410 *
411 * crypto_alloc_base() will first attempt to locate an already loaded
412 * algorithm. If that fails and the kernel supports dynamically loadable
413 * modules, it will then attempt to load a module of the same name or
414 * alias. If that fails it will send a query to any loaded crypto manager
415 * to construct an algorithm on the fly. A refcount is grabbed on the
416 * algorithm which is then associated with the new transform.
417 *
418 * The returned transform is of a non-determinate type. Most people
419 * should use one of the more specific allocation functions such as
420 * crypto_alloc_blkcipher.
421 *
422 * In case of error the return value is an error pointer.
423 */
424struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
425{
426 struct crypto_tfm *tfm;
427 int err;
428
429 for (;;) {
430 struct crypto_alg *alg;
431
432 alg = crypto_alg_mod_lookup(alg_name, type, mask);
433 if (IS_ERR(alg)) {
434 err = PTR_ERR(alg);
435 goto err;
436 }
437
438 tfm = __crypto_alloc_tfm(alg, type, mask);
439 if (!IS_ERR(tfm))
440 return tfm;
441
442 crypto_mod_put(alg);
443 err = PTR_ERR(tfm);
444
445err:
446 if (err != -EAGAIN)
447 break;
448 if (fatal_signal_pending(current)) {
449 err = -EINTR;
450 break;
451 }
452 }
453
454 return ERR_PTR(err);
455}
456EXPORT_SYMBOL_GPL(crypto_alloc_base);
457
458void *crypto_create_tfm(struct crypto_alg *alg,
459 const struct crypto_type *frontend)
460{
461 char *mem;
462 struct crypto_tfm *tfm = NULL;
463 unsigned int tfmsize;
464 unsigned int total;
465 int err = -ENOMEM;
466
467 tfmsize = frontend->tfmsize;
468 total = tfmsize + sizeof(*tfm) + frontend->extsize(alg);
469
470 mem = kzalloc(total, GFP_KERNEL);
471 if (mem == NULL)
472 goto out_err;
473
474 tfm = (struct crypto_tfm *)(mem + tfmsize);
475 tfm->__crt_alg = alg;
476
477 err = frontend->init_tfm(tfm);
478 if (err)
479 goto out_free_tfm;
480
481 if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
482 goto cra_init_failed;
483
484 goto out;
485
486cra_init_failed:
487 crypto_exit_ops(tfm);
488out_free_tfm:
489 if (err == -EAGAIN)
490 crypto_shoot_alg(alg);
491 kfree(mem);
492out_err:
493 mem = ERR_PTR(err);
494out:
495 return mem;
496}
497EXPORT_SYMBOL_GPL(crypto_create_tfm);
498
499struct crypto_alg *crypto_find_alg(const char *alg_name,
500 const struct crypto_type *frontend,
501 u32 type, u32 mask)
502{
503 struct crypto_alg *(*lookup)(const char *name, u32 type, u32 mask) =
504 crypto_alg_mod_lookup;
505
506 if (frontend) {
507 type &= frontend->maskclear;
508 mask &= frontend->maskclear;
509 type |= frontend->type;
510 mask |= frontend->maskset;
511
512 if (frontend->lookup)
513 lookup = frontend->lookup;
514 }
515
516 return lookup(alg_name, type, mask);
517}
518EXPORT_SYMBOL_GPL(crypto_find_alg);
519
520/*
521 * crypto_alloc_tfm - Locate algorithm and allocate transform
522 * @alg_name: Name of algorithm
523 * @frontend: Frontend algorithm type
524 * @type: Type of algorithm
525 * @mask: Mask for type comparison
526 *
527 * crypto_alloc_tfm() will first attempt to locate an already loaded
528 * algorithm. If that fails and the kernel supports dynamically loadable
529 * modules, it will then attempt to load a module of the same name or
530 * alias. If that fails it will send a query to any loaded crypto manager
531 * to construct an algorithm on the fly. A refcount is grabbed on the
532 * algorithm which is then associated with the new transform.
533 *
534 * The returned transform is of a non-determinate type. Most people
535 * should use one of the more specific allocation functions such as
536 * crypto_alloc_blkcipher.
537 *
538 * In case of error the return value is an error pointer.
539 */
540void *crypto_alloc_tfm(const char *alg_name,
541 const struct crypto_type *frontend, u32 type, u32 mask)
542{
543 void *tfm;
544 int err;
545
546 for (;;) {
547 struct crypto_alg *alg;
548
549 alg = crypto_find_alg(alg_name, frontend, type, mask);
550 if (IS_ERR(alg)) {
551 err = PTR_ERR(alg);
552 goto err;
553 }
554
555 tfm = crypto_create_tfm(alg, frontend);
556 if (!IS_ERR(tfm))
557 return tfm;
558
559 crypto_mod_put(alg);
560 err = PTR_ERR(tfm);
561
562err:
563 if (err != -EAGAIN)
564 break;
565 if (fatal_signal_pending(current)) {
566 err = -EINTR;
567 break;
568 }
569 }
570
571 return ERR_PTR(err);
572}
573EXPORT_SYMBOL_GPL(crypto_alloc_tfm);
574
575/*
576 * crypto_destroy_tfm - Free crypto transform
577 * @mem: Start of tfm slab
578 * @tfm: Transform to free
579 *
580 * This function frees up the transform and any associated resources,
581 * then drops the refcount on the associated algorithm.
582 */
583void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm)
584{
585 struct crypto_alg *alg;
586
587 if (unlikely(!mem))
588 return;
589
590 alg = tfm->__crt_alg;
591
592 if (!tfm->exit && alg->cra_exit)
593 alg->cra_exit(tfm);
594 crypto_exit_ops(tfm);
595 crypto_mod_put(alg);
596 kzfree(mem);
597}
598EXPORT_SYMBOL_GPL(crypto_destroy_tfm);
599
600int crypto_has_alg(const char *name, u32 type, u32 mask)
601{
602 int ret = 0;
603 struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
604
605 if (!IS_ERR(alg)) {
606 crypto_mod_put(alg);
607 ret = 1;
608 }
609
610 return ret;
611}
612EXPORT_SYMBOL_GPL(crypto_has_alg);
613
614MODULE_DESCRIPTION("Cryptographic core API");
615MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Scatterlist Cryptographic API.
4 *
5 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
6 * Copyright (c) 2002 David S. Miller (davem@redhat.com)
7 * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
8 *
9 * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
10 * and Nettle, by Niels Möller.
11 */
12
13#include <linux/err.h>
14#include <linux/errno.h>
15#include <linux/kernel.h>
16#include <linux/kmod.h>
17#include <linux/module.h>
18#include <linux/param.h>
19#include <linux/sched/signal.h>
20#include <linux/slab.h>
21#include <linux/string.h>
22#include <linux/completion.h>
23#include "internal.h"
24
25LIST_HEAD(crypto_alg_list);
26EXPORT_SYMBOL_GPL(crypto_alg_list);
27DECLARE_RWSEM(crypto_alg_sem);
28EXPORT_SYMBOL_GPL(crypto_alg_sem);
29
30BLOCKING_NOTIFIER_HEAD(crypto_chain);
31EXPORT_SYMBOL_GPL(crypto_chain);
32
33static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg);
34
35struct crypto_alg *crypto_mod_get(struct crypto_alg *alg)
36{
37 return try_module_get(alg->cra_module) ? crypto_alg_get(alg) : NULL;
38}
39EXPORT_SYMBOL_GPL(crypto_mod_get);
40
41void crypto_mod_put(struct crypto_alg *alg)
42{
43 struct module *module = alg->cra_module;
44
45 crypto_alg_put(alg);
46 module_put(module);
47}
48EXPORT_SYMBOL_GPL(crypto_mod_put);
49
50static inline int crypto_is_test_larval(struct crypto_larval *larval)
51{
52 return larval->alg.cra_driver_name[0];
53}
54
55static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type,
56 u32 mask)
57{
58 struct crypto_alg *q, *alg = NULL;
59 int best = -2;
60
61 list_for_each_entry(q, &crypto_alg_list, cra_list) {
62 int exact, fuzzy;
63
64 if (crypto_is_moribund(q))
65 continue;
66
67 if ((q->cra_flags ^ type) & mask)
68 continue;
69
70 if (crypto_is_larval(q) &&
71 !crypto_is_test_larval((struct crypto_larval *)q) &&
72 ((struct crypto_larval *)q)->mask != mask)
73 continue;
74
75 exact = !strcmp(q->cra_driver_name, name);
76 fuzzy = !strcmp(q->cra_name, name);
77 if (!exact && !(fuzzy && q->cra_priority > best))
78 continue;
79
80 if (unlikely(!crypto_mod_get(q)))
81 continue;
82
83 best = q->cra_priority;
84 if (alg)
85 crypto_mod_put(alg);
86 alg = q;
87
88 if (exact)
89 break;
90 }
91
92 return alg;
93}
94
95static void crypto_larval_destroy(struct crypto_alg *alg)
96{
97 struct crypto_larval *larval = (void *)alg;
98
99 BUG_ON(!crypto_is_larval(alg));
100 if (!IS_ERR_OR_NULL(larval->adult))
101 crypto_mod_put(larval->adult);
102 kfree(larval);
103}
104
105struct crypto_larval *crypto_larval_alloc(const char *name, u32 type, u32 mask)
106{
107 struct crypto_larval *larval;
108
109 larval = kzalloc(sizeof(*larval), GFP_KERNEL);
110 if (!larval)
111 return ERR_PTR(-ENOMEM);
112
113 larval->mask = mask;
114 larval->alg.cra_flags = CRYPTO_ALG_LARVAL | type;
115 larval->alg.cra_priority = -1;
116 larval->alg.cra_destroy = crypto_larval_destroy;
117
118 strlcpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME);
119 init_completion(&larval->completion);
120
121 return larval;
122}
123EXPORT_SYMBOL_GPL(crypto_larval_alloc);
124
125static struct crypto_alg *crypto_larval_add(const char *name, u32 type,
126 u32 mask)
127{
128 struct crypto_alg *alg;
129 struct crypto_larval *larval;
130
131 larval = crypto_larval_alloc(name, type, mask);
132 if (IS_ERR(larval))
133 return ERR_CAST(larval);
134
135 refcount_set(&larval->alg.cra_refcnt, 2);
136
137 down_write(&crypto_alg_sem);
138 alg = __crypto_alg_lookup(name, type, mask);
139 if (!alg) {
140 alg = &larval->alg;
141 list_add(&alg->cra_list, &crypto_alg_list);
142 }
143 up_write(&crypto_alg_sem);
144
145 if (alg != &larval->alg) {
146 kfree(larval);
147 if (crypto_is_larval(alg))
148 alg = crypto_larval_wait(alg);
149 }
150
151 return alg;
152}
153
154void crypto_larval_kill(struct crypto_alg *alg)
155{
156 struct crypto_larval *larval = (void *)alg;
157
158 down_write(&crypto_alg_sem);
159 list_del(&alg->cra_list);
160 up_write(&crypto_alg_sem);
161 complete_all(&larval->completion);
162 crypto_alg_put(alg);
163}
164EXPORT_SYMBOL_GPL(crypto_larval_kill);
165
166static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg)
167{
168 struct crypto_larval *larval = (void *)alg;
169 long timeout;
170
171 timeout = wait_for_completion_killable_timeout(
172 &larval->completion, 60 * HZ);
173
174 alg = larval->adult;
175 if (timeout < 0)
176 alg = ERR_PTR(-EINTR);
177 else if (!timeout)
178 alg = ERR_PTR(-ETIMEDOUT);
179 else if (!alg)
180 alg = ERR_PTR(-ENOENT);
181 else if (IS_ERR(alg))
182 ;
183 else if (crypto_is_test_larval(larval) &&
184 !(alg->cra_flags & CRYPTO_ALG_TESTED))
185 alg = ERR_PTR(-EAGAIN);
186 else if (!crypto_mod_get(alg))
187 alg = ERR_PTR(-EAGAIN);
188 crypto_mod_put(&larval->alg);
189
190 return alg;
191}
192
193static struct crypto_alg *crypto_alg_lookup(const char *name, u32 type,
194 u32 mask)
195{
196 struct crypto_alg *alg;
197 u32 test = 0;
198
199 if (!((type | mask) & CRYPTO_ALG_TESTED))
200 test |= CRYPTO_ALG_TESTED;
201
202 down_read(&crypto_alg_sem);
203 alg = __crypto_alg_lookup(name, type | test, mask | test);
204 if (!alg && test) {
205 alg = __crypto_alg_lookup(name, type, mask);
206 if (alg && !crypto_is_larval(alg)) {
207 /* Test failed */
208 crypto_mod_put(alg);
209 alg = ERR_PTR(-ELIBBAD);
210 }
211 }
212 up_read(&crypto_alg_sem);
213
214 return alg;
215}
216
217static struct crypto_alg *crypto_larval_lookup(const char *name, u32 type,
218 u32 mask)
219{
220 struct crypto_alg *alg;
221
222 if (!name)
223 return ERR_PTR(-ENOENT);
224
225 type &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
226 mask &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
227
228 alg = crypto_alg_lookup(name, type, mask);
229 if (!alg && !(mask & CRYPTO_NOLOAD)) {
230 request_module("crypto-%s", name);
231
232 if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask &
233 CRYPTO_ALG_NEED_FALLBACK))
234 request_module("crypto-%s-all", name);
235
236 alg = crypto_alg_lookup(name, type, mask);
237 }
238
239 if (!IS_ERR_OR_NULL(alg) && crypto_is_larval(alg))
240 alg = crypto_larval_wait(alg);
241 else if (!alg)
242 alg = crypto_larval_add(name, type, mask);
243
244 return alg;
245}
246
247int crypto_probing_notify(unsigned long val, void *v)
248{
249 int ok;
250
251 ok = blocking_notifier_call_chain(&crypto_chain, val, v);
252 if (ok == NOTIFY_DONE) {
253 request_module("cryptomgr");
254 ok = blocking_notifier_call_chain(&crypto_chain, val, v);
255 }
256
257 return ok;
258}
259EXPORT_SYMBOL_GPL(crypto_probing_notify);
260
261struct crypto_alg *crypto_alg_mod_lookup(const char *name, u32 type, u32 mask)
262{
263 struct crypto_alg *alg;
264 struct crypto_alg *larval;
265 int ok;
266
267 /*
268 * If the internal flag is set for a cipher, require a caller to
269 * to invoke the cipher with the internal flag to use that cipher.
270 * Also, if a caller wants to allocate a cipher that may or may
271 * not be an internal cipher, use type | CRYPTO_ALG_INTERNAL and
272 * !(mask & CRYPTO_ALG_INTERNAL).
273 */
274 if (!((type | mask) & CRYPTO_ALG_INTERNAL))
275 mask |= CRYPTO_ALG_INTERNAL;
276
277 larval = crypto_larval_lookup(name, type, mask);
278 if (IS_ERR(larval) || !crypto_is_larval(larval))
279 return larval;
280
281 ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);
282
283 if (ok == NOTIFY_STOP)
284 alg = crypto_larval_wait(larval);
285 else {
286 crypto_mod_put(larval);
287 alg = ERR_PTR(-ENOENT);
288 }
289 crypto_larval_kill(larval);
290 return alg;
291}
292EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
293
294static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
295{
296 const struct crypto_type *type_obj = tfm->__crt_alg->cra_type;
297
298 if (type_obj)
299 return type_obj->init(tfm, type, mask);
300 return 0;
301}
302
303static void crypto_exit_ops(struct crypto_tfm *tfm)
304{
305 const struct crypto_type *type = tfm->__crt_alg->cra_type;
306
307 if (type && tfm->exit)
308 tfm->exit(tfm);
309}
310
311static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask)
312{
313 const struct crypto_type *type_obj = alg->cra_type;
314 unsigned int len;
315
316 len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1);
317 if (type_obj)
318 return len + type_obj->ctxsize(alg, type, mask);
319
320 switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
321 default:
322 BUG();
323
324 case CRYPTO_ALG_TYPE_CIPHER:
325 len += crypto_cipher_ctxsize(alg);
326 break;
327
328 case CRYPTO_ALG_TYPE_COMPRESS:
329 len += crypto_compress_ctxsize(alg);
330 break;
331 }
332
333 return len;
334}
335
336void crypto_shoot_alg(struct crypto_alg *alg)
337{
338 down_write(&crypto_alg_sem);
339 alg->cra_flags |= CRYPTO_ALG_DYING;
340 up_write(&crypto_alg_sem);
341}
342EXPORT_SYMBOL_GPL(crypto_shoot_alg);
343
344struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type,
345 u32 mask)
346{
347 struct crypto_tfm *tfm = NULL;
348 unsigned int tfm_size;
349 int err = -ENOMEM;
350
351 tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
352 tfm = kzalloc(tfm_size, GFP_KERNEL);
353 if (tfm == NULL)
354 goto out_err;
355
356 tfm->__crt_alg = alg;
357
358 err = crypto_init_ops(tfm, type, mask);
359 if (err)
360 goto out_free_tfm;
361
362 if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
363 goto cra_init_failed;
364
365 goto out;
366
367cra_init_failed:
368 crypto_exit_ops(tfm);
369out_free_tfm:
370 if (err == -EAGAIN)
371 crypto_shoot_alg(alg);
372 kfree(tfm);
373out_err:
374 tfm = ERR_PTR(err);
375out:
376 return tfm;
377}
378EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
379
380/*
381 * crypto_alloc_base - Locate algorithm and allocate transform
382 * @alg_name: Name of algorithm
383 * @type: Type of algorithm
384 * @mask: Mask for type comparison
385 *
386 * This function should not be used by new algorithm types.
387 * Please use crypto_alloc_tfm instead.
388 *
389 * crypto_alloc_base() will first attempt to locate an already loaded
390 * algorithm. If that fails and the kernel supports dynamically loadable
391 * modules, it will then attempt to load a module of the same name or
392 * alias. If that fails it will send a query to any loaded crypto manager
393 * to construct an algorithm on the fly. A refcount is grabbed on the
394 * algorithm which is then associated with the new transform.
395 *
396 * The returned transform is of a non-determinate type. Most people
397 * should use one of the more specific allocation functions such as
398 * crypto_alloc_skcipher().
399 *
400 * In case of error the return value is an error pointer.
401 */
402struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
403{
404 struct crypto_tfm *tfm;
405 int err;
406
407 for (;;) {
408 struct crypto_alg *alg;
409
410 alg = crypto_alg_mod_lookup(alg_name, type, mask);
411 if (IS_ERR(alg)) {
412 err = PTR_ERR(alg);
413 goto err;
414 }
415
416 tfm = __crypto_alloc_tfm(alg, type, mask);
417 if (!IS_ERR(tfm))
418 return tfm;
419
420 crypto_mod_put(alg);
421 err = PTR_ERR(tfm);
422
423err:
424 if (err != -EAGAIN)
425 break;
426 if (fatal_signal_pending(current)) {
427 err = -EINTR;
428 break;
429 }
430 }
431
432 return ERR_PTR(err);
433}
434EXPORT_SYMBOL_GPL(crypto_alloc_base);
435
436void *crypto_create_tfm_node(struct crypto_alg *alg,
437 const struct crypto_type *frontend,
438 int node)
439{
440 char *mem;
441 struct crypto_tfm *tfm = NULL;
442 unsigned int tfmsize;
443 unsigned int total;
444 int err = -ENOMEM;
445
446 tfmsize = frontend->tfmsize;
447 total = tfmsize + sizeof(*tfm) + frontend->extsize(alg);
448
449 mem = kzalloc_node(total, GFP_KERNEL, node);
450 if (mem == NULL)
451 goto out_err;
452
453 tfm = (struct crypto_tfm *)(mem + tfmsize);
454 tfm->__crt_alg = alg;
455 tfm->node = node;
456
457 err = frontend->init_tfm(tfm);
458 if (err)
459 goto out_free_tfm;
460
461 if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
462 goto cra_init_failed;
463
464 goto out;
465
466cra_init_failed:
467 crypto_exit_ops(tfm);
468out_free_tfm:
469 if (err == -EAGAIN)
470 crypto_shoot_alg(alg);
471 kfree(mem);
472out_err:
473 mem = ERR_PTR(err);
474out:
475 return mem;
476}
477EXPORT_SYMBOL_GPL(crypto_create_tfm_node);
478
479struct crypto_alg *crypto_find_alg(const char *alg_name,
480 const struct crypto_type *frontend,
481 u32 type, u32 mask)
482{
483 if (frontend) {
484 type &= frontend->maskclear;
485 mask &= frontend->maskclear;
486 type |= frontend->type;
487 mask |= frontend->maskset;
488 }
489
490 return crypto_alg_mod_lookup(alg_name, type, mask);
491}
492EXPORT_SYMBOL_GPL(crypto_find_alg);
493
494/*
495 * crypto_alloc_tfm_node - Locate algorithm and allocate transform
496 * @alg_name: Name of algorithm
497 * @frontend: Frontend algorithm type
498 * @type: Type of algorithm
499 * @mask: Mask for type comparison
500 * @node: NUMA node in which users desire to put requests, if node is
501 * NUMA_NO_NODE, it means users have no special requirement.
502 *
503 * crypto_alloc_tfm() will first attempt to locate an already loaded
504 * algorithm. If that fails and the kernel supports dynamically loadable
505 * modules, it will then attempt to load a module of the same name or
506 * alias. If that fails it will send a query to any loaded crypto manager
507 * to construct an algorithm on the fly. A refcount is grabbed on the
508 * algorithm which is then associated with the new transform.
509 *
510 * The returned transform is of a non-determinate type. Most people
511 * should use one of the more specific allocation functions such as
512 * crypto_alloc_skcipher().
513 *
514 * In case of error the return value is an error pointer.
515 */
516
517void *crypto_alloc_tfm_node(const char *alg_name,
518 const struct crypto_type *frontend, u32 type, u32 mask,
519 int node)
520{
521 void *tfm;
522 int err;
523
524 for (;;) {
525 struct crypto_alg *alg;
526
527 alg = crypto_find_alg(alg_name, frontend, type, mask);
528 if (IS_ERR(alg)) {
529 err = PTR_ERR(alg);
530 goto err;
531 }
532
533 tfm = crypto_create_tfm_node(alg, frontend, node);
534 if (!IS_ERR(tfm))
535 return tfm;
536
537 crypto_mod_put(alg);
538 err = PTR_ERR(tfm);
539
540err:
541 if (err != -EAGAIN)
542 break;
543 if (fatal_signal_pending(current)) {
544 err = -EINTR;
545 break;
546 }
547 }
548
549 return ERR_PTR(err);
550}
551EXPORT_SYMBOL_GPL(crypto_alloc_tfm_node);
552
553/*
554 * crypto_destroy_tfm - Free crypto transform
555 * @mem: Start of tfm slab
556 * @tfm: Transform to free
557 *
558 * This function frees up the transform and any associated resources,
559 * then drops the refcount on the associated algorithm.
560 */
561void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm)
562{
563 struct crypto_alg *alg;
564
565 if (IS_ERR_OR_NULL(mem))
566 return;
567
568 alg = tfm->__crt_alg;
569
570 if (!tfm->exit && alg->cra_exit)
571 alg->cra_exit(tfm);
572 crypto_exit_ops(tfm);
573 crypto_mod_put(alg);
574 kfree_sensitive(mem);
575}
576EXPORT_SYMBOL_GPL(crypto_destroy_tfm);
577
578int crypto_has_alg(const char *name, u32 type, u32 mask)
579{
580 int ret = 0;
581 struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
582
583 if (!IS_ERR(alg)) {
584 crypto_mod_put(alg);
585 ret = 1;
586 }
587
588 return ret;
589}
590EXPORT_SYMBOL_GPL(crypto_has_alg);
591
592void crypto_req_done(struct crypto_async_request *req, int err)
593{
594 struct crypto_wait *wait = req->data;
595
596 if (err == -EINPROGRESS)
597 return;
598
599 wait->err = err;
600 complete(&wait->completion);
601}
602EXPORT_SYMBOL_GPL(crypto_req_done);
603
604MODULE_DESCRIPTION("Cryptographic core API");
605MODULE_LICENSE("GPL");
606MODULE_SOFTDEP("pre: cryptomgr");