Commit | Line | Data |
---|---|---|
1da177e4 LT |
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) | |
5cb1454b | 6 | * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au> |
1da177e4 LT |
7 | * |
8 | * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no> | |
991d1740 | 9 | * and Nettle, by Niels Möller. |
1da177e4 LT |
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 | |
3d01a33b | 13 | * Software Foundation; either version 2 of the License, or (at your option) |
1da177e4 LT |
14 | * any later version. |
15 | * | |
16 | */ | |
a61cc448 | 17 | |
6bfd4809 | 18 | #include <linux/err.h> |
1da177e4 | 19 | #include <linux/errno.h> |
5cb1454b | 20 | #include <linux/kernel.h> |
176c3652 | 21 | #include <linux/kmod.h> |
2b8c19db | 22 | #include <linux/module.h> |
2825982d | 23 | #include <linux/param.h> |
6bfd4809 | 24 | #include <linux/sched.h> |
1da177e4 | 25 | #include <linux/slab.h> |
5cb1454b | 26 | #include <linux/string.h> |
1da177e4 LT |
27 | #include "internal.h" |
28 | ||
29 | LIST_HEAD(crypto_alg_list); | |
cce9e06d | 30 | EXPORT_SYMBOL_GPL(crypto_alg_list); |
1da177e4 | 31 | DECLARE_RWSEM(crypto_alg_sem); |
cce9e06d | 32 | EXPORT_SYMBOL_GPL(crypto_alg_sem); |
1da177e4 | 33 | |
2825982d HX |
34 | BLOCKING_NOTIFIER_HEAD(crypto_chain); |
35 | EXPORT_SYMBOL_GPL(crypto_chain); | |
36 | ||
2825982d | 37 | struct crypto_alg *crypto_mod_get(struct crypto_alg *alg) |
6521f302 HX |
38 | { |
39 | return try_module_get(alg->cra_module) ? crypto_alg_get(alg) : NULL; | |
1da177e4 | 40 | } |
2825982d | 41 | EXPORT_SYMBOL_GPL(crypto_mod_get); |
1da177e4 | 42 | |
2825982d | 43 | void crypto_mod_put(struct crypto_alg *alg) |
1da177e4 | 44 | { |
da7cd59a HX |
45 | struct module *module = alg->cra_module; |
46 | ||
6521f302 | 47 | crypto_alg_put(alg); |
da7cd59a | 48 | module_put(module); |
1da177e4 | 49 | } |
2825982d | 50 | EXPORT_SYMBOL_GPL(crypto_mod_put); |
1da177e4 | 51 | |
73d3864a HX |
52 | static inline int crypto_is_test_larval(struct crypto_larval *larval) |
53 | { | |
54 | return larval->alg.cra_driver_name[0]; | |
55 | } | |
56 | ||
c51b6c81 HX |
57 | static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type, |
58 | u32 mask) | |
1da177e4 LT |
59 | { |
60 | struct crypto_alg *q, *alg = NULL; | |
2825982d | 61 | int best = -2; |
1da177e4 | 62 | |
1da177e4 | 63 | list_for_each_entry(q, &crypto_alg_list, cra_list) { |
5cb1454b HX |
64 | int exact, fuzzy; |
65 | ||
6bfd4809 HX |
66 | if (crypto_is_moribund(q)) |
67 | continue; | |
68 | ||
492e2b63 HX |
69 | if ((q->cra_flags ^ type) & mask) |
70 | continue; | |
71 | ||
72 | if (crypto_is_larval(q) && | |
73d3864a | 73 | !crypto_is_test_larval((struct crypto_larval *)q) && |
492e2b63 HX |
74 | ((struct crypto_larval *)q)->mask != mask) |
75 | continue; | |
76 | ||
5cb1454b HX |
77 | exact = !strcmp(q->cra_driver_name, name); |
78 | fuzzy = !strcmp(q->cra_name, name); | |
79 | if (!exact && !(fuzzy && q->cra_priority > best)) | |
80 | continue; | |
81 | ||
72fa4919 | 82 | if (unlikely(!crypto_mod_get(q))) |
5cb1454b HX |
83 | continue; |
84 | ||
85 | best = q->cra_priority; | |
86 | if (alg) | |
72fa4919 | 87 | crypto_mod_put(alg); |
5cb1454b HX |
88 | alg = q; |
89 | ||
90 | if (exact) | |
1da177e4 | 91 | break; |
1da177e4 | 92 | } |
2825982d HX |
93 | |
94 | return alg; | |
95 | } | |
2825982d HX |
96 | |
97 | static void crypto_larval_destroy(struct crypto_alg *alg) | |
98 | { | |
99 | struct crypto_larval *larval = (void *)alg; | |
100 | ||
101 | BUG_ON(!crypto_is_larval(alg)); | |
102 | if (larval->adult) | |
103 | crypto_mod_put(larval->adult); | |
104 | kfree(larval); | |
105 | } | |
106 | ||
73d3864a | 107 | struct crypto_larval *crypto_larval_alloc(const char *name, u32 type, u32 mask) |
2825982d | 108 | { |
2825982d HX |
109 | struct crypto_larval *larval; |
110 | ||
111 | larval = kzalloc(sizeof(*larval), GFP_KERNEL); | |
112 | if (!larval) | |
6bfd4809 | 113 | return ERR_PTR(-ENOMEM); |
2825982d | 114 | |
492e2b63 HX |
115 | larval->mask = mask; |
116 | larval->alg.cra_flags = CRYPTO_ALG_LARVAL | type; | |
2825982d HX |
117 | larval->alg.cra_priority = -1; |
118 | larval->alg.cra_destroy = crypto_larval_destroy; | |
119 | ||
2825982d HX |
120 | strlcpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME); |
121 | init_completion(&larval->completion); | |
122 | ||
73d3864a HX |
123 | return larval; |
124 | } | |
125 | EXPORT_SYMBOL_GPL(crypto_larval_alloc); | |
126 | ||
127 | static struct crypto_alg *crypto_larval_add(const char *name, u32 type, | |
128 | u32 mask) | |
129 | { | |
130 | struct crypto_alg *alg; | |
131 | struct crypto_larval *larval; | |
132 | ||
133 | larval = crypto_larval_alloc(name, type, mask); | |
134 | if (IS_ERR(larval)) | |
135 | return ERR_CAST(larval); | |
136 | ||
137 | atomic_set(&larval->alg.cra_refcnt, 2); | |
138 | ||
2825982d | 139 | down_write(&crypto_alg_sem); |
492e2b63 | 140 | alg = __crypto_alg_lookup(name, type, mask); |
2825982d HX |
141 | if (!alg) { |
142 | alg = &larval->alg; | |
143 | list_add(&alg->cra_list, &crypto_alg_list); | |
144 | } | |
145 | up_write(&crypto_alg_sem); | |
146 | ||
147 | if (alg != &larval->alg) | |
148 | kfree(larval); | |
149 | ||
150 | return alg; | |
151 | } | |
152 | ||
b9c55aa4 | 153 | void crypto_larval_kill(struct crypto_alg *alg) |
2825982d HX |
154 | { |
155 | struct crypto_larval *larval = (void *)alg; | |
156 | ||
157 | down_write(&crypto_alg_sem); | |
158 | list_del(&alg->cra_list); | |
159 | up_write(&crypto_alg_sem); | |
fe3c5206 | 160 | complete_all(&larval->completion); |
2825982d HX |
161 | crypto_alg_put(alg); |
162 | } | |
b9c55aa4 | 163 | EXPORT_SYMBOL_GPL(crypto_larval_kill); |
2825982d HX |
164 | |
165 | static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg) | |
166 | { | |
167 | struct crypto_larval *larval = (void *)alg; | |
73d3864a HX |
168 | long timeout; |
169 | ||
170 | timeout = wait_for_completion_interruptible_timeout( | |
171 | &larval->completion, 60 * HZ); | |
2825982d | 172 | |
2825982d | 173 | alg = larval->adult; |
73d3864a HX |
174 | if (timeout < 0) |
175 | alg = ERR_PTR(-EINTR); | |
176 | else if (!timeout) | |
177 | alg = ERR_PTR(-ETIMEDOUT); | |
178 | else if (!alg) | |
6bfd4809 | 179 | alg = ERR_PTR(-ENOENT); |
73d3864a HX |
180 | else if (crypto_is_test_larval(larval) && |
181 | !(alg->cra_flags & CRYPTO_ALG_TESTED)) | |
182 | alg = ERR_PTR(-EAGAIN); | |
183 | else if (!crypto_mod_get(alg)) | |
184 | alg = ERR_PTR(-EAGAIN); | |
2825982d HX |
185 | crypto_mod_put(&larval->alg); |
186 | ||
187 | return alg; | |
188 | } | |
189 | ||
c51b6c81 | 190 | struct crypto_alg *crypto_alg_lookup(const char *name, u32 type, u32 mask) |
2825982d HX |
191 | { |
192 | struct crypto_alg *alg; | |
193 | ||
2825982d | 194 | down_read(&crypto_alg_sem); |
492e2b63 | 195 | alg = __crypto_alg_lookup(name, type, mask); |
1da177e4 | 196 | up_read(&crypto_alg_sem); |
2825982d | 197 | |
1da177e4 LT |
198 | return alg; |
199 | } | |
c51b6c81 | 200 | EXPORT_SYMBOL_GPL(crypto_alg_lookup); |
1da177e4 | 201 | |
b9c55aa4 | 202 | struct crypto_alg *crypto_larval_lookup(const char *name, u32 type, u32 mask) |
176c3652 | 203 | { |
2825982d | 204 | struct crypto_alg *alg; |
2825982d | 205 | |
6bfd4809 HX |
206 | if (!name) |
207 | return ERR_PTR(-ENOENT); | |
208 | ||
209 | mask &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD); | |
492e2b63 HX |
210 | type &= mask; |
211 | ||
a760a665 HX |
212 | alg = crypto_alg_lookup(name, type, mask); |
213 | if (!alg) { | |
aa07a699 | 214 | request_module("%s", name); |
a760a665 | 215 | |
37fc334c | 216 | if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask & |
aa07a699 AR |
217 | CRYPTO_ALG_NEED_FALLBACK)) |
218 | request_module("%s-all", name); | |
a760a665 HX |
219 | |
220 | alg = crypto_alg_lookup(name, type, mask); | |
221 | } | |
222 | ||
2825982d HX |
223 | if (alg) |
224 | return crypto_is_larval(alg) ? crypto_larval_wait(alg) : alg; | |
225 | ||
73d3864a | 226 | return crypto_larval_add(name, type, mask); |
b9c55aa4 HX |
227 | } |
228 | EXPORT_SYMBOL_GPL(crypto_larval_lookup); | |
229 | ||
73d3864a HX |
230 | int crypto_probing_notify(unsigned long val, void *v) |
231 | { | |
232 | int ok; | |
233 | ||
234 | ok = blocking_notifier_call_chain(&crypto_chain, val, v); | |
235 | if (ok == NOTIFY_DONE) { | |
236 | request_module("cryptomgr"); | |
237 | ok = blocking_notifier_call_chain(&crypto_chain, val, v); | |
238 | } | |
239 | ||
240 | return ok; | |
241 | } | |
242 | EXPORT_SYMBOL_GPL(crypto_probing_notify); | |
243 | ||
b9c55aa4 HX |
244 | struct crypto_alg *crypto_alg_mod_lookup(const char *name, u32 type, u32 mask) |
245 | { | |
246 | struct crypto_alg *alg; | |
247 | struct crypto_alg *larval; | |
248 | int ok; | |
249 | ||
ff753308 | 250 | if (!((type | mask) & CRYPTO_ALG_TESTED)) { |
73d3864a HX |
251 | type |= CRYPTO_ALG_TESTED; |
252 | mask |= CRYPTO_ALG_TESTED; | |
253 | } | |
254 | ||
b9c55aa4 | 255 | larval = crypto_larval_lookup(name, type, mask); |
6bfd4809 | 256 | if (IS_ERR(larval) || !crypto_is_larval(larval)) |
2825982d HX |
257 | return larval; |
258 | ||
73d3864a | 259 | ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval); |
2b8c19db HX |
260 | |
261 | if (ok == NOTIFY_STOP) | |
2825982d HX |
262 | alg = crypto_larval_wait(larval); |
263 | else { | |
264 | crypto_mod_put(larval); | |
6bfd4809 | 265 | alg = ERR_PTR(-ENOENT); |
2825982d HX |
266 | } |
267 | crypto_larval_kill(larval); | |
268 | return alg; | |
176c3652 | 269 | } |
492e2b63 | 270 | EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup); |
176c3652 | 271 | |
27d2a330 | 272 | static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask) |
1da177e4 | 273 | { |
27d2a330 | 274 | const struct crypto_type *type_obj = tfm->__crt_alg->cra_type; |
e853c3cf | 275 | |
27d2a330 HX |
276 | if (type_obj) |
277 | return type_obj->init(tfm, type, mask); | |
e853c3cf | 278 | |
1da177e4 LT |
279 | switch (crypto_tfm_alg_type(tfm)) { |
280 | case CRYPTO_ALG_TYPE_CIPHER: | |
281 | return crypto_init_cipher_ops(tfm); | |
004a403c | 282 | |
1da177e4 LT |
283 | case CRYPTO_ALG_TYPE_COMPRESS: |
284 | return crypto_init_compress_ops(tfm); | |
3d01a33b | 285 | |
1da177e4 LT |
286 | default: |
287 | break; | |
288 | } | |
3d01a33b | 289 | |
1da177e4 LT |
290 | BUG(); |
291 | return -EINVAL; | |
292 | } | |
293 | ||
294 | static void crypto_exit_ops(struct crypto_tfm *tfm) | |
295 | { | |
e853c3cf HX |
296 | const struct crypto_type *type = tfm->__crt_alg->cra_type; |
297 | ||
298 | if (type) { | |
4a779486 HX |
299 | if (tfm->exit) |
300 | tfm->exit(tfm); | |
e853c3cf HX |
301 | return; |
302 | } | |
303 | ||
1da177e4 LT |
304 | switch (crypto_tfm_alg_type(tfm)) { |
305 | case CRYPTO_ALG_TYPE_CIPHER: | |
306 | crypto_exit_cipher_ops(tfm); | |
307 | break; | |
6941c3a0 | 308 | |
1da177e4 LT |
309 | case CRYPTO_ALG_TYPE_COMPRESS: |
310 | crypto_exit_compress_ops(tfm); | |
311 | break; | |
3d01a33b | 312 | |
1da177e4 LT |
313 | default: |
314 | BUG(); | |
1da177e4 LT |
315 | } |
316 | } | |
317 | ||
27d2a330 | 318 | static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask) |
fbdae9f3 | 319 | { |
27d2a330 | 320 | const struct crypto_type *type_obj = alg->cra_type; |
fbdae9f3 HX |
321 | unsigned int len; |
322 | ||
e853c3cf | 323 | len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1); |
27d2a330 HX |
324 | if (type_obj) |
325 | return len + type_obj->ctxsize(alg, type, mask); | |
e853c3cf | 326 | |
fbdae9f3 HX |
327 | switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) { |
328 | default: | |
329 | BUG(); | |
330 | ||
331 | case CRYPTO_ALG_TYPE_CIPHER: | |
f1ddcaf3 | 332 | len += crypto_cipher_ctxsize(alg); |
fbdae9f3 | 333 | break; |
6941c3a0 | 334 | |
fbdae9f3 | 335 | case CRYPTO_ALG_TYPE_COMPRESS: |
f1ddcaf3 | 336 | len += crypto_compress_ctxsize(alg); |
fbdae9f3 HX |
337 | break; |
338 | } | |
339 | ||
e853c3cf | 340 | return len; |
fbdae9f3 HX |
341 | } |
342 | ||
6bfd4809 HX |
343 | void crypto_shoot_alg(struct crypto_alg *alg) |
344 | { | |
345 | down_write(&crypto_alg_sem); | |
346 | alg->cra_flags |= CRYPTO_ALG_DYING; | |
347 | up_write(&crypto_alg_sem); | |
348 | } | |
349 | EXPORT_SYMBOL_GPL(crypto_shoot_alg); | |
350 | ||
27d2a330 HX |
351 | struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type, |
352 | u32 mask) | |
1da177e4 LT |
353 | { |
354 | struct crypto_tfm *tfm = NULL; | |
fbdae9f3 | 355 | unsigned int tfm_size; |
6bfd4809 | 356 | int err = -ENOMEM; |
fbdae9f3 | 357 | |
27d2a330 | 358 | tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask); |
bbeb563f | 359 | tfm = kzalloc(tfm_size, GFP_KERNEL); |
1da177e4 | 360 | if (tfm == NULL) |
9765d262 | 361 | goto out_err; |
1da177e4 | 362 | |
1da177e4 | 363 | tfm->__crt_alg = alg; |
6bfd4809 | 364 | |
27d2a330 | 365 | err = crypto_init_ops(tfm, type, mask); |
6bfd4809 | 366 | if (err) |
1da177e4 | 367 | goto out_free_tfm; |
c7fc0599 | 368 | |
4a779486 | 369 | if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm))) |
c7fc0599 | 370 | goto cra_init_failed; |
1da177e4 LT |
371 | |
372 | goto out; | |
373 | ||
c7fc0599 HX |
374 | cra_init_failed: |
375 | crypto_exit_ops(tfm); | |
1da177e4 | 376 | out_free_tfm: |
4a779486 HX |
377 | if (err == -EAGAIN) |
378 | crypto_shoot_alg(alg); | |
1da177e4 | 379 | kfree(tfm); |
9765d262 | 380 | out_err: |
6bfd4809 | 381 | tfm = ERR_PTR(err); |
1da177e4 LT |
382 | out: |
383 | return tfm; | |
384 | } | |
6bfd4809 HX |
385 | EXPORT_SYMBOL_GPL(__crypto_alloc_tfm); |
386 | ||
6d7d684d HX |
387 | /* |
388 | * crypto_alloc_base - Locate algorithm and allocate transform | |
389 | * @alg_name: Name of algorithm | |
390 | * @type: Type of algorithm | |
391 | * @mask: Mask for type comparison | |
392 | * | |
7b0bac64 HX |
393 | * This function should not be used by new algorithm types. |
394 | * Plesae use crypto_alloc_tfm instead. | |
395 | * | |
6d7d684d HX |
396 | * crypto_alloc_base() will first attempt to locate an already loaded |
397 | * algorithm. If that fails and the kernel supports dynamically loadable | |
398 | * modules, it will then attempt to load a module of the same name or | |
399 | * alias. If that fails it will send a query to any loaded crypto manager | |
400 | * to construct an algorithm on the fly. A refcount is grabbed on the | |
401 | * algorithm which is then associated with the new transform. | |
402 | * | |
403 | * The returned transform is of a non-determinate type. Most people | |
404 | * should use one of the more specific allocation functions such as | |
405 | * crypto_alloc_blkcipher. | |
406 | * | |
407 | * In case of error the return value is an error pointer. | |
408 | */ | |
409 | struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask) | |
410 | { | |
411 | struct crypto_tfm *tfm; | |
412 | int err; | |
413 | ||
414 | for (;;) { | |
415 | struct crypto_alg *alg; | |
416 | ||
417 | alg = crypto_alg_mod_lookup(alg_name, type, mask); | |
9765d262 AM |
418 | if (IS_ERR(alg)) { |
419 | err = PTR_ERR(alg); | |
6d7d684d | 420 | goto err; |
9765d262 | 421 | } |
6d7d684d | 422 | |
27d2a330 | 423 | tfm = __crypto_alloc_tfm(alg, type, mask); |
6d7d684d | 424 | if (!IS_ERR(tfm)) |
9765d262 | 425 | return tfm; |
6d7d684d HX |
426 | |
427 | crypto_mod_put(alg); | |
428 | err = PTR_ERR(tfm); | |
429 | ||
430 | err: | |
431 | if (err != -EAGAIN) | |
432 | break; | |
433 | if (signal_pending(current)) { | |
434 | err = -EINTR; | |
435 | break; | |
436 | } | |
9765d262 | 437 | } |
6d7d684d | 438 | |
9765d262 | 439 | return ERR_PTR(err); |
6d7d684d HX |
440 | } |
441 | EXPORT_SYMBOL_GPL(crypto_alloc_base); | |
7b0bac64 | 442 | |
3f683d61 HX |
443 | void *crypto_create_tfm(struct crypto_alg *alg, |
444 | const struct crypto_type *frontend) | |
7b0bac64 HX |
445 | { |
446 | char *mem; | |
447 | struct crypto_tfm *tfm = NULL; | |
448 | unsigned int tfmsize; | |
449 | unsigned int total; | |
450 | int err = -ENOMEM; | |
451 | ||
452 | tfmsize = frontend->tfmsize; | |
2ca33da1 | 453 | total = tfmsize + sizeof(*tfm) + frontend->extsize(alg); |
7b0bac64 HX |
454 | |
455 | mem = kzalloc(total, GFP_KERNEL); | |
456 | if (mem == NULL) | |
457 | goto out_err; | |
458 | ||
459 | tfm = (struct crypto_tfm *)(mem + tfmsize); | |
460 | tfm->__crt_alg = alg; | |
461 | ||
2ca33da1 | 462 | err = frontend->init_tfm(tfm); |
7b0bac64 HX |
463 | if (err) |
464 | goto out_free_tfm; | |
465 | ||
466 | if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm))) | |
467 | goto cra_init_failed; | |
468 | ||
469 | goto out; | |
470 | ||
471 | cra_init_failed: | |
472 | crypto_exit_ops(tfm); | |
473 | out_free_tfm: | |
474 | if (err == -EAGAIN) | |
475 | crypto_shoot_alg(alg); | |
476 | kfree(mem); | |
477 | out_err: | |
3f683d61 | 478 | mem = ERR_PTR(err); |
7b0bac64 | 479 | out: |
3f683d61 | 480 | return mem; |
7b0bac64 HX |
481 | } |
482 | EXPORT_SYMBOL_GPL(crypto_create_tfm); | |
483 | ||
d06854f0 HX |
484 | struct crypto_alg *crypto_find_alg(const char *alg_name, |
485 | const struct crypto_type *frontend, | |
486 | u32 type, u32 mask) | |
487 | { | |
488 | struct crypto_alg *(*lookup)(const char *name, u32 type, u32 mask) = | |
489 | crypto_alg_mod_lookup; | |
490 | ||
491 | if (frontend) { | |
492 | type &= frontend->maskclear; | |
493 | mask &= frontend->maskclear; | |
494 | type |= frontend->type; | |
495 | mask |= frontend->maskset; | |
496 | ||
497 | if (frontend->lookup) | |
498 | lookup = frontend->lookup; | |
499 | } | |
500 | ||
501 | return lookup(alg_name, type, mask); | |
502 | } | |
503 | EXPORT_SYMBOL_GPL(crypto_find_alg); | |
504 | ||
7b0bac64 HX |
505 | /* |
506 | * crypto_alloc_tfm - Locate algorithm and allocate transform | |
507 | * @alg_name: Name of algorithm | |
508 | * @frontend: Frontend algorithm type | |
509 | * @type: Type of algorithm | |
510 | * @mask: Mask for type comparison | |
511 | * | |
512 | * crypto_alloc_tfm() will first attempt to locate an already loaded | |
513 | * algorithm. If that fails and the kernel supports dynamically loadable | |
514 | * modules, it will then attempt to load a module of the same name or | |
515 | * alias. If that fails it will send a query to any loaded crypto manager | |
516 | * to construct an algorithm on the fly. A refcount is grabbed on the | |
517 | * algorithm which is then associated with the new transform. | |
518 | * | |
519 | * The returned transform is of a non-determinate type. Most people | |
520 | * should use one of the more specific allocation functions such as | |
521 | * crypto_alloc_blkcipher. | |
522 | * | |
523 | * In case of error the return value is an error pointer. | |
524 | */ | |
3f683d61 HX |
525 | void *crypto_alloc_tfm(const char *alg_name, |
526 | const struct crypto_type *frontend, u32 type, u32 mask) | |
7b0bac64 | 527 | { |
3f683d61 | 528 | void *tfm; |
7b0bac64 HX |
529 | int err; |
530 | ||
7b0bac64 HX |
531 | for (;;) { |
532 | struct crypto_alg *alg; | |
533 | ||
d06854f0 | 534 | alg = crypto_find_alg(alg_name, frontend, type, mask); |
7b0bac64 HX |
535 | if (IS_ERR(alg)) { |
536 | err = PTR_ERR(alg); | |
537 | goto err; | |
538 | } | |
539 | ||
540 | tfm = crypto_create_tfm(alg, frontend); | |
541 | if (!IS_ERR(tfm)) | |
542 | return tfm; | |
543 | ||
544 | crypto_mod_put(alg); | |
545 | err = PTR_ERR(tfm); | |
546 | ||
547 | err: | |
548 | if (err != -EAGAIN) | |
549 | break; | |
550 | if (signal_pending(current)) { | |
551 | err = -EINTR; | |
552 | break; | |
553 | } | |
554 | } | |
555 | ||
556 | return ERR_PTR(err); | |
557 | } | |
558 | EXPORT_SYMBOL_GPL(crypto_alloc_tfm); | |
7b2cd92a | 559 | |
6d7d684d | 560 | /* |
7b2cd92a HX |
561 | * crypto_destroy_tfm - Free crypto transform |
562 | * @mem: Start of tfm slab | |
6d7d684d HX |
563 | * @tfm: Transform to free |
564 | * | |
7b2cd92a | 565 | * This function frees up the transform and any associated resources, |
6d7d684d HX |
566 | * then drops the refcount on the associated algorithm. |
567 | */ | |
7b2cd92a | 568 | void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm) |
1da177e4 | 569 | { |
a61cc448 | 570 | struct crypto_alg *alg; |
a61cc448 | 571 | |
7b2cd92a | 572 | if (unlikely(!mem)) |
a61cc448 JJ |
573 | return; |
574 | ||
575 | alg = tfm->__crt_alg; | |
1da177e4 | 576 | |
4a779486 | 577 | if (!tfm->exit && alg->cra_exit) |
c7fc0599 | 578 | alg->cra_exit(tfm); |
1da177e4 | 579 | crypto_exit_ops(tfm); |
72fa4919 | 580 | crypto_mod_put(alg); |
811d8f06 | 581 | kzfree(mem); |
1da177e4 | 582 | } |
7b2cd92a | 583 | EXPORT_SYMBOL_GPL(crypto_destroy_tfm); |
fce32d70 HX |
584 | |
585 | int crypto_has_alg(const char *name, u32 type, u32 mask) | |
586 | { | |
587 | int ret = 0; | |
588 | struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask); | |
3d01a33b | 589 | |
fce32d70 HX |
590 | if (!IS_ERR(alg)) { |
591 | crypto_mod_put(alg); | |
592 | ret = 1; | |
593 | } | |
3d01a33b | 594 | |
fce32d70 HX |
595 | return ret; |
596 | } | |
597 | EXPORT_SYMBOL_GPL(crypto_has_alg); | |
c3715cb9 SS |
598 | |
599 | MODULE_DESCRIPTION("Cryptographic core API"); | |
600 | MODULE_LICENSE("GPL"); |