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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 = try_then_request_module(crypto_alg_lookup(name, type, mask),
219 name);
220 if (alg)
221 return crypto_is_larval(alg) ? crypto_larval_wait(alg) : alg;
222
223 return crypto_larval_add(name, type, mask);
224}
225EXPORT_SYMBOL_GPL(crypto_larval_lookup);
226
227int crypto_probing_notify(unsigned long val, void *v)
228{
229 int ok;
230
231 ok = blocking_notifier_call_chain(&crypto_chain, val, v);
232 if (ok == NOTIFY_DONE) {
233 request_module("cryptomgr");
234 ok = blocking_notifier_call_chain(&crypto_chain, val, v);
235 }
236
237 return ok;
238}
239EXPORT_SYMBOL_GPL(crypto_probing_notify);
240
241struct crypto_alg *crypto_alg_mod_lookup(const char *name, u32 type, u32 mask)
242{
243 struct crypto_alg *alg;
244 struct crypto_alg *larval;
245 int ok;
246
247 if (!(mask & CRYPTO_ALG_TESTED)) {
248 type |= CRYPTO_ALG_TESTED;
249 mask |= CRYPTO_ALG_TESTED;
250 }
251
252 larval = crypto_larval_lookup(name, type, mask);
253 if (IS_ERR(larval) || !crypto_is_larval(larval))
254 return larval;
255
256 ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);
257
258 if (ok == NOTIFY_STOP)
259 alg = crypto_larval_wait(larval);
260 else {
261 crypto_mod_put(larval);
262 alg = ERR_PTR(-ENOENT);
263 }
264 crypto_larval_kill(larval);
265 return alg;
266}
267EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
268
269static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
270{
271 const struct crypto_type *type_obj = tfm->__crt_alg->cra_type;
272
273 if (type_obj)
274 return type_obj->init(tfm, type, mask);
275
276 switch (crypto_tfm_alg_type(tfm)) {
277 case CRYPTO_ALG_TYPE_CIPHER:
278 return crypto_init_cipher_ops(tfm);
279
280 case CRYPTO_ALG_TYPE_DIGEST:
281 if ((mask & CRYPTO_ALG_TYPE_HASH_MASK) !=
282 CRYPTO_ALG_TYPE_HASH_MASK)
283 return crypto_init_digest_ops_async(tfm);
284 else
285 return crypto_init_digest_ops(tfm);
286
287 case CRYPTO_ALG_TYPE_COMPRESS:
288 return crypto_init_compress_ops(tfm);
289
290 default:
291 break;
292 }
293
294 BUG();
295 return -EINVAL;
296}
297
298static void crypto_exit_ops(struct crypto_tfm *tfm)
299{
300 const struct crypto_type *type = tfm->__crt_alg->cra_type;
301
302 if (type) {
303 if (type->exit)
304 type->exit(tfm);
305 return;
306 }
307
308 switch (crypto_tfm_alg_type(tfm)) {
309 case CRYPTO_ALG_TYPE_CIPHER:
310 crypto_exit_cipher_ops(tfm);
311 break;
312
313 case CRYPTO_ALG_TYPE_DIGEST:
314 crypto_exit_digest_ops(tfm);
315 break;
316
317 case CRYPTO_ALG_TYPE_COMPRESS:
318 crypto_exit_compress_ops(tfm);
319 break;
320
321 default:
322 BUG();
323
324 }
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_DIGEST:
345 len += crypto_digest_ctxsize(alg);
346 break;
347
348 case CRYPTO_ALG_TYPE_COMPRESS:
349 len += crypto_compress_ctxsize(alg);
350 break;
351 }
352
353 return len;
354}
355
356void crypto_shoot_alg(struct crypto_alg *alg)
357{
358 down_write(&crypto_alg_sem);
359 alg->cra_flags |= CRYPTO_ALG_DYING;
360 up_write(&crypto_alg_sem);
361}
362EXPORT_SYMBOL_GPL(crypto_shoot_alg);
363
364struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type,
365 u32 mask)
366{
367 struct crypto_tfm *tfm = NULL;
368 unsigned int tfm_size;
369 int err = -ENOMEM;
370
371 tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
372 tfm = kzalloc(tfm_size, GFP_KERNEL);
373 if (tfm == NULL)
374 goto out_err;
375
376 tfm->__crt_alg = alg;
377
378 err = crypto_init_ops(tfm, type, mask);
379 if (err)
380 goto out_free_tfm;
381
382 if (alg->cra_init && (err = alg->cra_init(tfm))) {
383 if (err == -EAGAIN)
384 crypto_shoot_alg(alg);
385 goto cra_init_failed;
386 }
387
388 goto out;
389
390cra_init_failed:
391 crypto_exit_ops(tfm);
392out_free_tfm:
393 kfree(tfm);
394out_err:
395 tfm = ERR_PTR(err);
396out:
397 return tfm;
398}
399EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
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420struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
421{
422 struct crypto_tfm *tfm;
423 int err;
424
425 for (;;) {
426 struct crypto_alg *alg;
427
428 alg = crypto_alg_mod_lookup(alg_name, type, mask);
429 if (IS_ERR(alg)) {
430 err = PTR_ERR(alg);
431 goto err;
432 }
433
434 tfm = __crypto_alloc_tfm(alg, type, mask);
435 if (!IS_ERR(tfm))
436 return tfm;
437
438 crypto_mod_put(alg);
439 err = PTR_ERR(tfm);
440
441err:
442 if (err != -EAGAIN)
443 break;
444 if (signal_pending(current)) {
445 err = -EINTR;
446 break;
447 }
448 }
449
450 return ERR_PTR(err);
451}
452EXPORT_SYMBOL_GPL(crypto_alloc_base);
453
454
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458
459
460
461void crypto_free_tfm(struct crypto_tfm *tfm)
462{
463 struct crypto_alg *alg;
464 int size;
465
466 if (unlikely(!tfm))
467 return;
468
469 alg = tfm->__crt_alg;
470 size = sizeof(*tfm) + alg->cra_ctxsize;
471
472 if (alg->cra_exit)
473 alg->cra_exit(tfm);
474 crypto_exit_ops(tfm);
475 crypto_mod_put(alg);
476 memset(tfm, 0, size);
477 kfree(tfm);
478}
479
480EXPORT_SYMBOL_GPL(crypto_free_tfm);
481
482int crypto_has_alg(const char *name, u32 type, u32 mask)
483{
484 int ret = 0;
485 struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
486
487 if (!IS_ERR(alg)) {
488 crypto_mod_put(alg);
489 ret = 1;
490 }
491
492 return ret;
493}
494EXPORT_SYMBOL_GPL(crypto_has_alg);
495
496MODULE_DESCRIPTION("Cryptographic core API");
497MODULE_LICENSE("GPL");
498
