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Commit | Line | Data |
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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 | ||
77dbd7a9 HX |
37 | static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg); |
38 | ||
2825982d | 39 | struct crypto_alg *crypto_mod_get(struct crypto_alg *alg) |
6521f302 HX |
40 | { |
41 | return try_module_get(alg->cra_module) ? crypto_alg_get(alg) : NULL; | |
1da177e4 | 42 | } |
2825982d | 43 | EXPORT_SYMBOL_GPL(crypto_mod_get); |
1da177e4 | 44 | |
2825982d | 45 | void crypto_mod_put(struct crypto_alg *alg) |
1da177e4 | 46 | { |
da7cd59a HX |
47 | struct module *module = alg->cra_module; |
48 | ||
6521f302 | 49 | crypto_alg_put(alg); |
da7cd59a | 50 | module_put(module); |
1da177e4 | 51 | } |
2825982d | 52 | EXPORT_SYMBOL_GPL(crypto_mod_put); |
1da177e4 | 53 | |
73d3864a HX |
54 | static inline int crypto_is_test_larval(struct crypto_larval *larval) |
55 | { | |
56 | return larval->alg.cra_driver_name[0]; | |
57 | } | |
58 | ||
c51b6c81 HX |
59 | static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type, |
60 | u32 mask) | |
1da177e4 LT |
61 | { |
62 | struct crypto_alg *q, *alg = NULL; | |
2825982d | 63 | int best = -2; |
1da177e4 | 64 | |
1da177e4 | 65 | list_for_each_entry(q, &crypto_alg_list, cra_list) { |
5cb1454b HX |
66 | int exact, fuzzy; |
67 | ||
6bfd4809 HX |
68 | if (crypto_is_moribund(q)) |
69 | continue; | |
70 | ||
492e2b63 HX |
71 | if ((q->cra_flags ^ type) & mask) |
72 | continue; | |
73 | ||
74 | if (crypto_is_larval(q) && | |
73d3864a | 75 | !crypto_is_test_larval((struct crypto_larval *)q) && |
492e2b63 HX |
76 | ((struct crypto_larval *)q)->mask != mask) |
77 | continue; | |
78 | ||
5cb1454b HX |
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 | ||
72fa4919 | 84 | if (unlikely(!crypto_mod_get(q))) |
5cb1454b HX |
85 | continue; |
86 | ||
87 | best = q->cra_priority; | |
88 | if (alg) | |
72fa4919 | 89 | crypto_mod_put(alg); |
5cb1454b HX |
90 | alg = q; |
91 | ||
92 | if (exact) | |
1da177e4 | 93 | break; |
1da177e4 | 94 | } |
2825982d HX |
95 | |
96 | return alg; | |
97 | } | |
2825982d HX |
98 | |
99 | static 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 | ||
73d3864a | 109 | struct crypto_larval *crypto_larval_alloc(const char *name, u32 type, u32 mask) |
2825982d | 110 | { |
2825982d HX |
111 | struct crypto_larval *larval; |
112 | ||
113 | larval = kzalloc(sizeof(*larval), GFP_KERNEL); | |
114 | if (!larval) | |
6bfd4809 | 115 | return ERR_PTR(-ENOMEM); |
2825982d | 116 | |
492e2b63 HX |
117 | larval->mask = mask; |
118 | larval->alg.cra_flags = CRYPTO_ALG_LARVAL | type; | |
2825982d HX |
119 | larval->alg.cra_priority = -1; |
120 | larval->alg.cra_destroy = crypto_larval_destroy; | |
121 | ||
2825982d HX |
122 | strlcpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME); |
123 | init_completion(&larval->completion); | |
124 | ||
73d3864a HX |
125 | return larval; |
126 | } | |
127 | EXPORT_SYMBOL_GPL(crypto_larval_alloc); | |
128 | ||
129 | static 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 | ||
2825982d | 141 | down_write(&crypto_alg_sem); |
492e2b63 | 142 | alg = __crypto_alg_lookup(name, type, mask); |
2825982d HX |
143 | if (!alg) { |
144 | alg = &larval->alg; | |
145 | list_add(&alg->cra_list, &crypto_alg_list); | |
146 | } | |
147 | up_write(&crypto_alg_sem); | |
148 | ||
77dbd7a9 | 149 | if (alg != &larval->alg) { |
2825982d | 150 | kfree(larval); |
77dbd7a9 HX |
151 | if (crypto_is_larval(alg)) |
152 | alg = crypto_larval_wait(alg); | |
153 | } | |
2825982d HX |
154 | |
155 | return alg; | |
156 | } | |
157 | ||
b9c55aa4 | 158 | void crypto_larval_kill(struct crypto_alg *alg) |
2825982d HX |
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); | |
fe3c5206 | 165 | complete_all(&larval->completion); |
2825982d HX |
166 | crypto_alg_put(alg); |
167 | } | |
b9c55aa4 | 168 | EXPORT_SYMBOL_GPL(crypto_larval_kill); |
2825982d HX |
169 | |
170 | static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg) | |
171 | { | |
172 | struct crypto_larval *larval = (void *)alg; | |
73d3864a HX |
173 | long timeout; |
174 | ||
3fc89adb | 175 | timeout = wait_for_completion_killable_timeout( |
73d3864a | 176 | &larval->completion, 60 * HZ); |
2825982d | 177 | |
2825982d | 178 | alg = larval->adult; |
73d3864a HX |
179 | if (timeout < 0) |
180 | alg = ERR_PTR(-EINTR); | |
181 | else if (!timeout) | |
182 | alg = ERR_PTR(-ETIMEDOUT); | |
183 | else if (!alg) | |
6bfd4809 | 184 | alg = ERR_PTR(-ENOENT); |
73d3864a HX |
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); | |
2825982d HX |
190 | crypto_mod_put(&larval->alg); |
191 | ||
192 | return alg; | |
193 | } | |
194 | ||
c51b6c81 | 195 | struct crypto_alg *crypto_alg_lookup(const char *name, u32 type, u32 mask) |
2825982d HX |
196 | { |
197 | struct crypto_alg *alg; | |
198 | ||
2825982d | 199 | down_read(&crypto_alg_sem); |
492e2b63 | 200 | alg = __crypto_alg_lookup(name, type, mask); |
1da177e4 | 201 | up_read(&crypto_alg_sem); |
2825982d | 202 | |
1da177e4 LT |
203 | return alg; |
204 | } | |
c51b6c81 | 205 | EXPORT_SYMBOL_GPL(crypto_alg_lookup); |
1da177e4 | 206 | |
b9c55aa4 | 207 | struct crypto_alg *crypto_larval_lookup(const char *name, u32 type, u32 mask) |
176c3652 | 208 | { |
2825982d | 209 | struct crypto_alg *alg; |
2825982d | 210 | |
6bfd4809 HX |
211 | if (!name) |
212 | return ERR_PTR(-ENOENT); | |
213 | ||
214 | mask &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD); | |
492e2b63 HX |
215 | type &= mask; |
216 | ||
a760a665 HX |
217 | alg = crypto_alg_lookup(name, type, mask); |
218 | if (!alg) { | |
5d26a105 | 219 | request_module("crypto-%s", name); |
a760a665 | 220 | |
37fc334c | 221 | if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask & |
aa07a699 | 222 | CRYPTO_ALG_NEED_FALLBACK)) |
5d26a105 | 223 | request_module("crypto-%s-all", name); |
a760a665 HX |
224 | |
225 | alg = crypto_alg_lookup(name, type, mask); | |
226 | } | |
227 | ||
2825982d HX |
228 | if (alg) |
229 | return crypto_is_larval(alg) ? crypto_larval_wait(alg) : alg; | |
230 | ||
73d3864a | 231 | return crypto_larval_add(name, type, mask); |
b9c55aa4 HX |
232 | } |
233 | EXPORT_SYMBOL_GPL(crypto_larval_lookup); | |
234 | ||
73d3864a HX |
235 | int 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 | } | |
247 | EXPORT_SYMBOL_GPL(crypto_probing_notify); | |
248 | ||
b9c55aa4 HX |
249 | struct 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 | ||
ff753308 | 255 | if (!((type | mask) & CRYPTO_ALG_TESTED)) { |
73d3864a HX |
256 | type |= CRYPTO_ALG_TESTED; |
257 | mask |= CRYPTO_ALG_TESTED; | |
258 | } | |
259 | ||
06ca7f68 SM |
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 | ||
b9c55aa4 | 270 | larval = crypto_larval_lookup(name, type, mask); |
6bfd4809 | 271 | if (IS_ERR(larval) || !crypto_is_larval(larval)) |
2825982d HX |
272 | return larval; |
273 | ||
73d3864a | 274 | ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval); |
2b8c19db HX |
275 | |
276 | if (ok == NOTIFY_STOP) | |
2825982d HX |
277 | alg = crypto_larval_wait(larval); |
278 | else { | |
279 | crypto_mod_put(larval); | |
6bfd4809 | 280 | alg = ERR_PTR(-ENOENT); |
2825982d HX |
281 | } |
282 | crypto_larval_kill(larval); | |
283 | return alg; | |
176c3652 | 284 | } |
492e2b63 | 285 | EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup); |
176c3652 | 286 | |
27d2a330 | 287 | static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask) |
1da177e4 | 288 | { |
27d2a330 | 289 | const struct crypto_type *type_obj = tfm->__crt_alg->cra_type; |
e853c3cf | 290 | |
27d2a330 HX |
291 | if (type_obj) |
292 | return type_obj->init(tfm, type, mask); | |
e853c3cf | 293 | |
1da177e4 LT |
294 | switch (crypto_tfm_alg_type(tfm)) { |
295 | case CRYPTO_ALG_TYPE_CIPHER: | |
296 | return crypto_init_cipher_ops(tfm); | |
004a403c | 297 | |
1da177e4 LT |
298 | case CRYPTO_ALG_TYPE_COMPRESS: |
299 | return crypto_init_compress_ops(tfm); | |
3d01a33b | 300 | |
1da177e4 LT |
301 | default: |
302 | break; | |
303 | } | |
3d01a33b | 304 | |
1da177e4 LT |
305 | BUG(); |
306 | return -EINVAL; | |
307 | } | |
308 | ||
309 | static void crypto_exit_ops(struct crypto_tfm *tfm) | |
310 | { | |
e853c3cf HX |
311 | const struct crypto_type *type = tfm->__crt_alg->cra_type; |
312 | ||
9c8ae17b EB |
313 | if (type && tfm->exit) |
314 | tfm->exit(tfm); | |
1da177e4 LT |
315 | } |
316 | ||
27d2a330 | 317 | static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask) |
fbdae9f3 | 318 | { |
27d2a330 | 319 | const struct crypto_type *type_obj = alg->cra_type; |
fbdae9f3 HX |
320 | unsigned int len; |
321 | ||
e853c3cf | 322 | len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1); |
27d2a330 HX |
323 | if (type_obj) |
324 | return len + type_obj->ctxsize(alg, type, mask); | |
e853c3cf | 325 | |
fbdae9f3 HX |
326 | switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) { |
327 | default: | |
328 | BUG(); | |
329 | ||
330 | case CRYPTO_ALG_TYPE_CIPHER: | |
f1ddcaf3 | 331 | len += crypto_cipher_ctxsize(alg); |
fbdae9f3 | 332 | break; |
6941c3a0 | 333 | |
fbdae9f3 | 334 | case CRYPTO_ALG_TYPE_COMPRESS: |
f1ddcaf3 | 335 | len += crypto_compress_ctxsize(alg); |
fbdae9f3 HX |
336 | break; |
337 | } | |
338 | ||
e853c3cf | 339 | return len; |
fbdae9f3 HX |
340 | } |
341 | ||
6bfd4809 HX |
342 | void crypto_shoot_alg(struct crypto_alg *alg) |
343 | { | |
344 | down_write(&crypto_alg_sem); | |
345 | alg->cra_flags |= CRYPTO_ALG_DYING; | |
346 | up_write(&crypto_alg_sem); | |
347 | } | |
348 | EXPORT_SYMBOL_GPL(crypto_shoot_alg); | |
349 | ||
27d2a330 HX |
350 | struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type, |
351 | u32 mask) | |
1da177e4 LT |
352 | { |
353 | struct crypto_tfm *tfm = NULL; | |
fbdae9f3 | 354 | unsigned int tfm_size; |
6bfd4809 | 355 | int err = -ENOMEM; |
fbdae9f3 | 356 | |
27d2a330 | 357 | tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask); |
bbeb563f | 358 | tfm = kzalloc(tfm_size, GFP_KERNEL); |
1da177e4 | 359 | if (tfm == NULL) |
9765d262 | 360 | goto out_err; |
1da177e4 | 361 | |
1da177e4 | 362 | tfm->__crt_alg = alg; |
6bfd4809 | 363 | |
27d2a330 | 364 | err = crypto_init_ops(tfm, type, mask); |
6bfd4809 | 365 | if (err) |
1da177e4 | 366 | goto out_free_tfm; |
c7fc0599 | 367 | |
4a779486 | 368 | if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm))) |
c7fc0599 | 369 | goto cra_init_failed; |
1da177e4 LT |
370 | |
371 | goto out; | |
372 | ||
c7fc0599 HX |
373 | cra_init_failed: |
374 | crypto_exit_ops(tfm); | |
1da177e4 | 375 | out_free_tfm: |
4a779486 HX |
376 | if (err == -EAGAIN) |
377 | crypto_shoot_alg(alg); | |
1da177e4 | 378 | kfree(tfm); |
9765d262 | 379 | out_err: |
6bfd4809 | 380 | tfm = ERR_PTR(err); |
1da177e4 LT |
381 | out: |
382 | return tfm; | |
383 | } | |
6bfd4809 HX |
384 | EXPORT_SYMBOL_GPL(__crypto_alloc_tfm); |
385 | ||
6d7d684d HX |
386 | /* |
387 | * crypto_alloc_base - Locate algorithm and allocate transform | |
388 | * @alg_name: Name of algorithm | |
389 | * @type: Type of algorithm | |
390 | * @mask: Mask for type comparison | |
391 | * | |
7b0bac64 | 392 | * This function should not be used by new algorithm types. |
fd1a1900 | 393 | * Please use crypto_alloc_tfm instead. |
7b0bac64 | 394 | * |
6d7d684d HX |
395 | * crypto_alloc_base() will first attempt to locate an already loaded |
396 | * algorithm. If that fails and the kernel supports dynamically loadable | |
397 | * modules, it will then attempt to load a module of the same name or | |
398 | * alias. If that fails it will send a query to any loaded crypto manager | |
399 | * to construct an algorithm on the fly. A refcount is grabbed on the | |
400 | * algorithm which is then associated with the new transform. | |
401 | * | |
402 | * The returned transform is of a non-determinate type. Most people | |
403 | * should use one of the more specific allocation functions such as | |
404 | * crypto_alloc_blkcipher. | |
405 | * | |
406 | * In case of error the return value is an error pointer. | |
407 | */ | |
408 | struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask) | |
409 | { | |
410 | struct crypto_tfm *tfm; | |
411 | int err; | |
412 | ||
413 | for (;;) { | |
414 | struct crypto_alg *alg; | |
415 | ||
416 | alg = crypto_alg_mod_lookup(alg_name, type, mask); | |
9765d262 AM |
417 | if (IS_ERR(alg)) { |
418 | err = PTR_ERR(alg); | |
6d7d684d | 419 | goto err; |
9765d262 | 420 | } |
6d7d684d | 421 | |
27d2a330 | 422 | tfm = __crypto_alloc_tfm(alg, type, mask); |
6d7d684d | 423 | if (!IS_ERR(tfm)) |
9765d262 | 424 | return tfm; |
6d7d684d HX |
425 | |
426 | crypto_mod_put(alg); | |
427 | err = PTR_ERR(tfm); | |
428 | ||
429 | err: | |
430 | if (err != -EAGAIN) | |
431 | break; | |
3fc89adb | 432 | if (fatal_signal_pending(current)) { |
6d7d684d HX |
433 | err = -EINTR; |
434 | break; | |
435 | } | |
9765d262 | 436 | } |
6d7d684d | 437 | |
9765d262 | 438 | return ERR_PTR(err); |
6d7d684d HX |
439 | } |
440 | EXPORT_SYMBOL_GPL(crypto_alloc_base); | |
7b0bac64 | 441 | |
3f683d61 HX |
442 | void *crypto_create_tfm(struct crypto_alg *alg, |
443 | const struct crypto_type *frontend) | |
7b0bac64 HX |
444 | { |
445 | char *mem; | |
446 | struct crypto_tfm *tfm = NULL; | |
447 | unsigned int tfmsize; | |
448 | unsigned int total; | |
449 | int err = -ENOMEM; | |
450 | ||
451 | tfmsize = frontend->tfmsize; | |
2ca33da1 | 452 | total = tfmsize + sizeof(*tfm) + frontend->extsize(alg); |
7b0bac64 HX |
453 | |
454 | mem = kzalloc(total, GFP_KERNEL); | |
455 | if (mem == NULL) | |
456 | goto out_err; | |
457 | ||
458 | tfm = (struct crypto_tfm *)(mem + tfmsize); | |
459 | tfm->__crt_alg = alg; | |
460 | ||
2ca33da1 | 461 | err = frontend->init_tfm(tfm); |
7b0bac64 HX |
462 | if (err) |
463 | goto out_free_tfm; | |
464 | ||
465 | if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm))) | |
466 | goto cra_init_failed; | |
467 | ||
468 | goto out; | |
469 | ||
470 | cra_init_failed: | |
471 | crypto_exit_ops(tfm); | |
472 | out_free_tfm: | |
473 | if (err == -EAGAIN) | |
474 | crypto_shoot_alg(alg); | |
475 | kfree(mem); | |
476 | out_err: | |
3f683d61 | 477 | mem = ERR_PTR(err); |
7b0bac64 | 478 | out: |
3f683d61 | 479 | return mem; |
7b0bac64 HX |
480 | } |
481 | EXPORT_SYMBOL_GPL(crypto_create_tfm); | |
482 | ||
d06854f0 HX |
483 | struct crypto_alg *crypto_find_alg(const char *alg_name, |
484 | const struct crypto_type *frontend, | |
485 | u32 type, u32 mask) | |
486 | { | |
487 | struct crypto_alg *(*lookup)(const char *name, u32 type, u32 mask) = | |
488 | crypto_alg_mod_lookup; | |
489 | ||
490 | if (frontend) { | |
491 | type &= frontend->maskclear; | |
492 | mask &= frontend->maskclear; | |
493 | type |= frontend->type; | |
494 | mask |= frontend->maskset; | |
495 | ||
496 | if (frontend->lookup) | |
497 | lookup = frontend->lookup; | |
498 | } | |
499 | ||
500 | return lookup(alg_name, type, mask); | |
501 | } | |
502 | EXPORT_SYMBOL_GPL(crypto_find_alg); | |
503 | ||
7b0bac64 HX |
504 | /* |
505 | * crypto_alloc_tfm - Locate algorithm and allocate transform | |
506 | * @alg_name: Name of algorithm | |
507 | * @frontend: Frontend algorithm type | |
508 | * @type: Type of algorithm | |
509 | * @mask: Mask for type comparison | |
510 | * | |
511 | * crypto_alloc_tfm() will first attempt to locate an already loaded | |
512 | * algorithm. If that fails and the kernel supports dynamically loadable | |
513 | * modules, it will then attempt to load a module of the same name or | |
514 | * alias. If that fails it will send a query to any loaded crypto manager | |
515 | * to construct an algorithm on the fly. A refcount is grabbed on the | |
516 | * algorithm which is then associated with the new transform. | |
517 | * | |
518 | * The returned transform is of a non-determinate type. Most people | |
519 | * should use one of the more specific allocation functions such as | |
520 | * crypto_alloc_blkcipher. | |
521 | * | |
522 | * In case of error the return value is an error pointer. | |
523 | */ | |
3f683d61 HX |
524 | void *crypto_alloc_tfm(const char *alg_name, |
525 | const struct crypto_type *frontend, u32 type, u32 mask) | |
7b0bac64 | 526 | { |
3f683d61 | 527 | void *tfm; |
7b0bac64 HX |
528 | int err; |
529 | ||
7b0bac64 HX |
530 | for (;;) { |
531 | struct crypto_alg *alg; | |
532 | ||
d06854f0 | 533 | alg = crypto_find_alg(alg_name, frontend, type, mask); |
7b0bac64 HX |
534 | if (IS_ERR(alg)) { |
535 | err = PTR_ERR(alg); | |
536 | goto err; | |
537 | } | |
538 | ||
539 | tfm = crypto_create_tfm(alg, frontend); | |
540 | if (!IS_ERR(tfm)) | |
541 | return tfm; | |
542 | ||
543 | crypto_mod_put(alg); | |
544 | err = PTR_ERR(tfm); | |
545 | ||
546 | err: | |
547 | if (err != -EAGAIN) | |
548 | break; | |
3fc89adb | 549 | if (fatal_signal_pending(current)) { |
7b0bac64 HX |
550 | err = -EINTR; |
551 | break; | |
552 | } | |
553 | } | |
554 | ||
555 | return ERR_PTR(err); | |
556 | } | |
557 | EXPORT_SYMBOL_GPL(crypto_alloc_tfm); | |
7b2cd92a | 558 | |
6d7d684d | 559 | /* |
7b2cd92a HX |
560 | * crypto_destroy_tfm - Free crypto transform |
561 | * @mem: Start of tfm slab | |
6d7d684d HX |
562 | * @tfm: Transform to free |
563 | * | |
7b2cd92a | 564 | * This function frees up the transform and any associated resources, |
6d7d684d HX |
565 | * then drops the refcount on the associated algorithm. |
566 | */ | |
7b2cd92a | 567 | void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm) |
1da177e4 | 568 | { |
a61cc448 | 569 | struct crypto_alg *alg; |
a61cc448 | 570 | |
7b2cd92a | 571 | if (unlikely(!mem)) |
a61cc448 JJ |
572 | return; |
573 | ||
574 | alg = tfm->__crt_alg; | |
1da177e4 | 575 | |
4a779486 | 576 | if (!tfm->exit && alg->cra_exit) |
c7fc0599 | 577 | alg->cra_exit(tfm); |
1da177e4 | 578 | crypto_exit_ops(tfm); |
72fa4919 | 579 | crypto_mod_put(alg); |
811d8f06 | 580 | kzfree(mem); |
1da177e4 | 581 | } |
7b2cd92a | 582 | EXPORT_SYMBOL_GPL(crypto_destroy_tfm); |
fce32d70 HX |
583 | |
584 | int crypto_has_alg(const char *name, u32 type, u32 mask) | |
585 | { | |
586 | int ret = 0; | |
587 | struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask); | |
3d01a33b | 588 | |
fce32d70 HX |
589 | if (!IS_ERR(alg)) { |
590 | crypto_mod_put(alg); | |
591 | ret = 1; | |
592 | } | |
3d01a33b | 593 | |
fce32d70 HX |
594 | return ret; |
595 | } | |
596 | EXPORT_SYMBOL_GPL(crypto_has_alg); | |
c3715cb9 SS |
597 | |
598 | MODULE_DESCRIPTION("Cryptographic core API"); | |
599 | MODULE_LICENSE("GPL"); |