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 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_interruptible_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("%s", name);
220
221 if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask &
222 CRYPTO_ALG_NEED_FALLBACK))
223 request_module("%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 larval = crypto_larval_lookup(name, type, mask);
261 if (IS_ERR(larval) || !crypto_is_larval(larval))
262 return larval;
263
264 ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);
265
266 if (ok == NOTIFY_STOP)
267 alg = crypto_larval_wait(larval);
268 else {
269 crypto_mod_put(larval);
270 alg = ERR_PTR(-ENOENT);
271 }
272 crypto_larval_kill(larval);
273 return alg;
274}
275EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
276
277static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
278{
279 const struct crypto_type *type_obj = tfm->__crt_alg->cra_type;
280
281 if (type_obj)
282 return type_obj->init(tfm, type, mask);
283
284 switch (crypto_tfm_alg_type(tfm)) {
285 case CRYPTO_ALG_TYPE_CIPHER:
286 return crypto_init_cipher_ops(tfm);
287
288 case CRYPTO_ALG_TYPE_COMPRESS:
289 return crypto_init_compress_ops(tfm);
290
291 default:
292 break;
293 }
294
295 BUG();
296 return -EINVAL;
297}
298
299static void crypto_exit_ops(struct crypto_tfm *tfm)
300{
301 const struct crypto_type *type = tfm->__crt_alg->cra_type;
302
303 if (type) {
304 if (tfm->exit)
305 tfm->exit(tfm);
306 return;
307 }
308
309 switch (crypto_tfm_alg_type(tfm)) {
310 case CRYPTO_ALG_TYPE_CIPHER:
311 crypto_exit_cipher_ops(tfm);
312 break;
313
314 case CRYPTO_ALG_TYPE_COMPRESS:
315 crypto_exit_compress_ops(tfm);
316 break;
317
318 default:
319 BUG();
320 }
321}
322
323static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask)
324{
325 const struct crypto_type *type_obj = alg->cra_type;
326 unsigned int len;
327
328 len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1);
329 if (type_obj)
330 return len + type_obj->ctxsize(alg, type, mask);
331
332 switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
333 default:
334 BUG();
335
336 case CRYPTO_ALG_TYPE_CIPHER:
337 len += crypto_cipher_ctxsize(alg);
338 break;
339
340 case CRYPTO_ALG_TYPE_COMPRESS:
341 len += crypto_compress_ctxsize(alg);
342 break;
343 }
344
345 return len;
346}
347
348void crypto_shoot_alg(struct crypto_alg *alg)
349{
350 down_write(&crypto_alg_sem);
351 alg->cra_flags |= CRYPTO_ALG_DYING;
352 up_write(&crypto_alg_sem);
353}
354EXPORT_SYMBOL_GPL(crypto_shoot_alg);
355
356struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type,
357 u32 mask)
358{
359 struct crypto_tfm *tfm = NULL;
360 unsigned int tfm_size;
361 int err = -ENOMEM;
362
363 tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
364 tfm = kzalloc(tfm_size, GFP_KERNEL);
365 if (tfm == NULL)
366 goto out_err;
367
368 tfm->__crt_alg = alg;
369
370 err = crypto_init_ops(tfm, type, mask);
371 if (err)
372 goto out_free_tfm;
373
374 if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
375 goto cra_init_failed;
376
377 goto out;
378
379cra_init_failed:
380 crypto_exit_ops(tfm);
381out_free_tfm:
382 if (err == -EAGAIN)
383 crypto_shoot_alg(alg);
384 kfree(tfm);
385out_err:
386 tfm = ERR_PTR(err);
387out:
388 return tfm;
389}
390EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
391
392/*
393 * crypto_alloc_base - Locate algorithm and allocate transform
394 * @alg_name: Name of algorithm
395 * @type: Type of algorithm
396 * @mask: Mask for type comparison
397 *
398 * This function should not be used by new algorithm types.
399 * Please use crypto_alloc_tfm instead.
400 *
401 * crypto_alloc_base() will first attempt to locate an already loaded
402 * algorithm. If that fails and the kernel supports dynamically loadable
403 * modules, it will then attempt to load a module of the same name or
404 * alias. If that fails it will send a query to any loaded crypto manager
405 * to construct an algorithm on the fly. A refcount is grabbed on the
406 * algorithm which is then associated with the new transform.
407 *
408 * The returned transform is of a non-determinate type. Most people
409 * should use one of the more specific allocation functions such as
410 * crypto_alloc_blkcipher.
411 *
412 * In case of error the return value is an error pointer.
413 */
414struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
415{
416 struct crypto_tfm *tfm;
417 int err;
418
419 for (;;) {
420 struct crypto_alg *alg;
421
422 alg = crypto_alg_mod_lookup(alg_name, type, mask);
423 if (IS_ERR(alg)) {
424 err = PTR_ERR(alg);
425 goto err;
426 }
427
428 tfm = __crypto_alloc_tfm(alg, type, mask);
429 if (!IS_ERR(tfm))
430 return tfm;
431
432 crypto_mod_put(alg);
433 err = PTR_ERR(tfm);
434
435err:
436 if (err != -EAGAIN)
437 break;
438 if (signal_pending(current)) {
439 err = -EINTR;
440 break;
441 }
442 }
443
444 return ERR_PTR(err);
445}
446EXPORT_SYMBOL_GPL(crypto_alloc_base);
447
448void *crypto_create_tfm(struct crypto_alg *alg,
449 const struct crypto_type *frontend)
450{
451 char *mem;
452 struct crypto_tfm *tfm = NULL;
453 unsigned int tfmsize;
454 unsigned int total;
455 int err = -ENOMEM;
456
457 tfmsize = frontend->tfmsize;
458 total = tfmsize + sizeof(*tfm) + frontend->extsize(alg);
459
460 mem = kzalloc(total, GFP_KERNEL);
461 if (mem == NULL)
462 goto out_err;
463
464 tfm = (struct crypto_tfm *)(mem + tfmsize);
465 tfm->__crt_alg = alg;
466
467 err = frontend->init_tfm(tfm);
468 if (err)
469 goto out_free_tfm;
470
471 if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
472 goto cra_init_failed;
473
474 goto out;
475
476cra_init_failed:
477 crypto_exit_ops(tfm);
478out_free_tfm:
479 if (err == -EAGAIN)
480 crypto_shoot_alg(alg);
481 kfree(mem);
482out_err:
483 mem = ERR_PTR(err);
484out:
485 return mem;
486}
487EXPORT_SYMBOL_GPL(crypto_create_tfm);
488
489struct crypto_alg *crypto_find_alg(const char *alg_name,
490 const struct crypto_type *frontend,
491 u32 type, u32 mask)
492{
493 struct crypto_alg *(*lookup)(const char *name, u32 type, u32 mask) =
494 crypto_alg_mod_lookup;
495
496 if (frontend) {
497 type &= frontend->maskclear;
498 mask &= frontend->maskclear;
499 type |= frontend->type;
500 mask |= frontend->maskset;
501
502 if (frontend->lookup)
503 lookup = frontend->lookup;
504 }
505
506 return lookup(alg_name, type, mask);
507}
508EXPORT_SYMBOL_GPL(crypto_find_alg);
509
510/*
511 * crypto_alloc_tfm - Locate algorithm and allocate transform
512 * @alg_name: Name of algorithm
513 * @frontend: Frontend algorithm type
514 * @type: Type of algorithm
515 * @mask: Mask for type comparison
516 *
517 * crypto_alloc_tfm() will first attempt to locate an already loaded
518 * algorithm. If that fails and the kernel supports dynamically loadable
519 * modules, it will then attempt to load a module of the same name or
520 * alias. If that fails it will send a query to any loaded crypto manager
521 * to construct an algorithm on the fly. A refcount is grabbed on the
522 * algorithm which is then associated with the new transform.
523 *
524 * The returned transform is of a non-determinate type. Most people
525 * should use one of the more specific allocation functions such as
526 * crypto_alloc_blkcipher.
527 *
528 * In case of error the return value is an error pointer.
529 */
530void *crypto_alloc_tfm(const char *alg_name,
531 const struct crypto_type *frontend, u32 type, u32 mask)
532{
533 void *tfm;
534 int err;
535
536 for (;;) {
537 struct crypto_alg *alg;
538
539 alg = crypto_find_alg(alg_name, frontend, type, mask);
540 if (IS_ERR(alg)) {
541 err = PTR_ERR(alg);
542 goto err;
543 }
544
545 tfm = crypto_create_tfm(alg, frontend);
546 if (!IS_ERR(tfm))
547 return tfm;
548
549 crypto_mod_put(alg);
550 err = PTR_ERR(tfm);
551
552err:
553 if (err != -EAGAIN)
554 break;
555 if (signal_pending(current)) {
556 err = -EINTR;
557 break;
558 }
559 }
560
561 return ERR_PTR(err);
562}
563EXPORT_SYMBOL_GPL(crypto_alloc_tfm);
564
565/*
566 * crypto_destroy_tfm - Free crypto transform
567 * @mem: Start of tfm slab
568 * @tfm: Transform to free
569 *
570 * This function frees up the transform and any associated resources,
571 * then drops the refcount on the associated algorithm.
572 */
573void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm)
574{
575 struct crypto_alg *alg;
576
577 if (unlikely(!mem))
578 return;
579
580 alg = tfm->__crt_alg;
581
582 if (!tfm->exit && alg->cra_exit)
583 alg->cra_exit(tfm);
584 crypto_exit_ops(tfm);
585 crypto_mod_put(alg);
586 kzfree(mem);
587}
588EXPORT_SYMBOL_GPL(crypto_destroy_tfm);
589
590int crypto_has_alg(const char *name, u32 type, u32 mask)
591{
592 int ret = 0;
593 struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
594
595 if (!IS_ERR(alg)) {
596 crypto_mod_put(alg);
597 ret = 1;
598 }
599
600 return ret;
601}
602EXPORT_SYMBOL_GPL(crypto_has_alg);
603
604MODULE_DESCRIPTION("Cryptographic core API");
605MODULE_LICENSE("GPL");