blob: 314dab96840e2792ee7af4b205b2ab63722faac4 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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)
Herbert Xu5cb14542005-11-05 16:58:14 +11006 * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 *
8 * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
John Anthony Kazos Jr991d1742007-10-19 23:06:17 +02009 * and Nettle, by Niels Möller.
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 *
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 */
Jesper Juhla61cc442005-07-06 13:54:31 -070017
Herbert Xu6bfd4802006-09-21 11:39:29 +100018#include <linux/err.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/errno.h>
Herbert Xu5cb14542005-11-05 16:58:14 +110020#include <linux/kernel.h>
Adrian Bunk176c3652005-07-06 13:53:09 -070021#include <linux/kmod.h>
Herbert Xu2b8c19d2006-09-21 11:31:44 +100022#include <linux/module.h>
Herbert Xu28259822006-08-06 21:23:26 +100023#include <linux/param.h>
Herbert Xu6bfd4802006-09-21 11:39:29 +100024#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070025#include <linux/slab.h>
Herbert Xu5cb14542005-11-05 16:58:14 +110026#include <linux/string.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include "internal.h"
28
29LIST_HEAD(crypto_alg_list);
Herbert Xucce9e062006-08-21 21:08:13 +100030EXPORT_SYMBOL_GPL(crypto_alg_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -070031DECLARE_RWSEM(crypto_alg_sem);
Herbert Xucce9e062006-08-21 21:08:13 +100032EXPORT_SYMBOL_GPL(crypto_alg_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -070033
Herbert Xu28259822006-08-06 21:23:26 +100034BLOCKING_NOTIFIER_HEAD(crypto_chain);
35EXPORT_SYMBOL_GPL(crypto_chain);
36
Herbert Xu6521f302006-08-06 20:28:44 +100037static inline struct crypto_alg *crypto_alg_get(struct crypto_alg *alg)
Linus Torvalds1da177e2005-04-16 15:20:36 -070038{
Herbert Xu6521f302006-08-06 20:28:44 +100039 atomic_inc(&alg->cra_refcnt);
40 return alg;
Linus Torvalds1da177e2005-04-16 15:20:36 -070041}
42
Herbert Xu28259822006-08-06 21:23:26 +100043struct crypto_alg *crypto_mod_get(struct crypto_alg *alg)
Herbert Xu6521f302006-08-06 20:28:44 +100044{
45 return try_module_get(alg->cra_module) ? crypto_alg_get(alg) : NULL;
46}
Herbert Xu28259822006-08-06 21:23:26 +100047EXPORT_SYMBOL_GPL(crypto_mod_get);
Herbert Xu6521f302006-08-06 20:28:44 +100048
Herbert Xu28259822006-08-06 21:23:26 +100049void crypto_mod_put(struct crypto_alg *alg)
Herbert Xu6521f302006-08-06 20:28:44 +100050{
Herbert Xuda7cd592007-05-19 14:51:00 +100051 struct module *module = alg->cra_module;
52
Herbert Xu6521f302006-08-06 20:28:44 +100053 crypto_alg_put(alg);
Herbert Xuda7cd592007-05-19 14:51:00 +100054 module_put(module);
Linus Torvalds1da177e2005-04-16 15:20:36 -070055}
Herbert Xu28259822006-08-06 21:23:26 +100056EXPORT_SYMBOL_GPL(crypto_mod_put);
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
Herbert Xu73d38642008-08-03 21:15:23 +080058static inline int crypto_is_test_larval(struct crypto_larval *larval)
59{
60 return larval->alg.cra_driver_name[0];
61}
62
Herbert Xuc51b6c82008-08-04 11:44:59 +080063static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type,
64 u32 mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -070065{
66 struct crypto_alg *q, *alg = NULL;
Herbert Xu28259822006-08-06 21:23:26 +100067 int best = -2;
Linus Torvalds1da177e2005-04-16 15:20:36 -070068
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 list_for_each_entry(q, &crypto_alg_list, cra_list) {
Herbert Xu5cb14542005-11-05 16:58:14 +110070 int exact, fuzzy;
71
Herbert Xu6bfd4802006-09-21 11:39:29 +100072 if (crypto_is_moribund(q))
73 continue;
74
Herbert Xu492e2b62006-09-21 11:35:17 +100075 if ((q->cra_flags ^ type) & mask)
76 continue;
77
78 if (crypto_is_larval(q) &&
Herbert Xu73d38642008-08-03 21:15:23 +080079 !crypto_is_test_larval((struct crypto_larval *)q) &&
Herbert Xu492e2b62006-09-21 11:35:17 +100080 ((struct crypto_larval *)q)->mask != mask)
81 continue;
82
Herbert Xu5cb14542005-11-05 16:58:14 +110083 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
Herbert Xu72fa4912006-05-28 09:05:24 +100088 if (unlikely(!crypto_mod_get(q)))
Herbert Xu5cb14542005-11-05 16:58:14 +110089 continue;
90
91 best = q->cra_priority;
92 if (alg)
Herbert Xu72fa4912006-05-28 09:05:24 +100093 crypto_mod_put(alg);
Herbert Xu5cb14542005-11-05 16:58:14 +110094 alg = q;
95
96 if (exact)
Linus Torvalds1da177e2005-04-16 15:20:36 -070097 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -070098 }
Herbert Xu28259822006-08-06 21:23:26 +100099
100 return alg;
101}
Herbert Xu28259822006-08-06 21:23:26 +1000102
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
Herbert Xu73d38642008-08-03 21:15:23 +0800113struct crypto_larval *crypto_larval_alloc(const char *name, u32 type, u32 mask)
Herbert Xu28259822006-08-06 21:23:26 +1000114{
Herbert Xu28259822006-08-06 21:23:26 +1000115 struct crypto_larval *larval;
116
117 larval = kzalloc(sizeof(*larval), GFP_KERNEL);
118 if (!larval)
Herbert Xu6bfd4802006-09-21 11:39:29 +1000119 return ERR_PTR(-ENOMEM);
Herbert Xu28259822006-08-06 21:23:26 +1000120
Herbert Xu492e2b62006-09-21 11:35:17 +1000121 larval->mask = mask;
122 larval->alg.cra_flags = CRYPTO_ALG_LARVAL | type;
Herbert Xu28259822006-08-06 21:23:26 +1000123 larval->alg.cra_priority = -1;
124 larval->alg.cra_destroy = crypto_larval_destroy;
125
Herbert Xu28259822006-08-06 21:23:26 +1000126 strlcpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME);
127 init_completion(&larval->completion);
128
Herbert Xu73d38642008-08-03 21:15:23 +0800129 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
Herbert Xu28259822006-08-06 21:23:26 +1000145 down_write(&crypto_alg_sem);
Herbert Xu492e2b62006-09-21 11:35:17 +1000146 alg = __crypto_alg_lookup(name, type, mask);
Herbert Xu28259822006-08-06 21:23:26 +1000147 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
Herbert Xub9c55aa2007-12-04 12:46:48 +1100159void crypto_larval_kill(struct crypto_alg *alg)
Herbert Xu28259822006-08-06 21:23:26 +1000160{
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);
Herbert Xufe3c5202007-05-19 17:51:40 +1000166 complete_all(&larval->completion);
Herbert Xu28259822006-08-06 21:23:26 +1000167 crypto_alg_put(alg);
168}
Herbert Xub9c55aa2007-12-04 12:46:48 +1100169EXPORT_SYMBOL_GPL(crypto_larval_kill);
Herbert Xu28259822006-08-06 21:23:26 +1000170
171static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg)
172{
173 struct crypto_larval *larval = (void *)alg;
Herbert Xu73d38642008-08-03 21:15:23 +0800174 long timeout;
Herbert Xu28259822006-08-06 21:23:26 +1000175
Herbert Xu73d38642008-08-03 21:15:23 +0800176 timeout = wait_for_completion_interruptible_timeout(
177 &larval->completion, 60 * HZ);
178
Herbert Xu28259822006-08-06 21:23:26 +1000179 alg = larval->adult;
Herbert Xu73d38642008-08-03 21:15:23 +0800180 if (timeout < 0)
181 alg = ERR_PTR(-EINTR);
182 else if (!timeout)
183 alg = ERR_PTR(-ETIMEDOUT);
184 else if (!alg)
Herbert Xu6bfd4802006-09-21 11:39:29 +1000185 alg = ERR_PTR(-ENOENT);
Herbert Xu73d38642008-08-03 21:15:23 +0800186 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);
Herbert Xu28259822006-08-06 21:23:26 +1000191 crypto_mod_put(&larval->alg);
192
193 return alg;
194}
195
Herbert Xuc51b6c82008-08-04 11:44:59 +0800196struct crypto_alg *crypto_alg_lookup(const char *name, u32 type, u32 mask)
Herbert Xu28259822006-08-06 21:23:26 +1000197{
198 struct crypto_alg *alg;
199
Herbert Xu28259822006-08-06 21:23:26 +1000200 down_read(&crypto_alg_sem);
Herbert Xu492e2b62006-09-21 11:35:17 +1000201 alg = __crypto_alg_lookup(name, type, mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 up_read(&crypto_alg_sem);
Herbert Xu28259822006-08-06 21:23:26 +1000203
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 return alg;
205}
Herbert Xuc51b6c82008-08-04 11:44:59 +0800206EXPORT_SYMBOL_GPL(crypto_alg_lookup);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207
Herbert Xub9c55aa2007-12-04 12:46:48 +1100208struct crypto_alg *crypto_larval_lookup(const char *name, u32 type, u32 mask)
Adrian Bunk176c3652005-07-06 13:53:09 -0700209{
Herbert Xu28259822006-08-06 21:23:26 +1000210 struct crypto_alg *alg;
Herbert Xu28259822006-08-06 21:23:26 +1000211
Herbert Xu6bfd4802006-09-21 11:39:29 +1000212 if (!name)
213 return ERR_PTR(-ENOENT);
214
215 mask &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
Herbert Xu492e2b62006-09-21 11:35:17 +1000216 type &= mask;
217
Herbert Xua760a662009-02-26 14:06:31 +0800218 alg = crypto_alg_lookup(name, type, mask);
219 if (!alg) {
220 char tmp[CRYPTO_MAX_ALG_NAME];
221
222 request_module(name);
223
224 if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask) &&
225 snprintf(tmp, sizeof(tmp), "%s-all", name) < sizeof(tmp))
226 request_module(tmp);
227
228 alg = crypto_alg_lookup(name, type, mask);
229 }
230
Herbert Xu28259822006-08-06 21:23:26 +1000231 if (alg)
232 return crypto_is_larval(alg) ? crypto_larval_wait(alg) : alg;
233
Herbert Xu73d38642008-08-03 21:15:23 +0800234 return crypto_larval_add(name, type, mask);
Herbert Xub9c55aa2007-12-04 12:46:48 +1100235}
236EXPORT_SYMBOL_GPL(crypto_larval_lookup);
237
Herbert Xu73d38642008-08-03 21:15:23 +0800238int crypto_probing_notify(unsigned long val, void *v)
239{
240 int ok;
241
242 ok = blocking_notifier_call_chain(&crypto_chain, val, v);
243 if (ok == NOTIFY_DONE) {
244 request_module("cryptomgr");
245 ok = blocking_notifier_call_chain(&crypto_chain, val, v);
246 }
247
248 return ok;
249}
250EXPORT_SYMBOL_GPL(crypto_probing_notify);
251
Herbert Xub9c55aa2007-12-04 12:46:48 +1100252struct crypto_alg *crypto_alg_mod_lookup(const char *name, u32 type, u32 mask)
253{
254 struct crypto_alg *alg;
255 struct crypto_alg *larval;
256 int ok;
257
Herbert Xuff753302009-02-17 20:18:34 +0800258 if (!((type | mask) & CRYPTO_ALG_TESTED)) {
Herbert Xu73d38642008-08-03 21:15:23 +0800259 type |= CRYPTO_ALG_TESTED;
260 mask |= CRYPTO_ALG_TESTED;
261 }
262
Herbert Xub9c55aa2007-12-04 12:46:48 +1100263 larval = crypto_larval_lookup(name, type, mask);
Herbert Xu6bfd4802006-09-21 11:39:29 +1000264 if (IS_ERR(larval) || !crypto_is_larval(larval))
Herbert Xu28259822006-08-06 21:23:26 +1000265 return larval;
266
Herbert Xu73d38642008-08-03 21:15:23 +0800267 ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);
Herbert Xu2b8c19d2006-09-21 11:31:44 +1000268
269 if (ok == NOTIFY_STOP)
Herbert Xu28259822006-08-06 21:23:26 +1000270 alg = crypto_larval_wait(larval);
271 else {
272 crypto_mod_put(larval);
Herbert Xu6bfd4802006-09-21 11:39:29 +1000273 alg = ERR_PTR(-ENOENT);
Herbert Xu28259822006-08-06 21:23:26 +1000274 }
275 crypto_larval_kill(larval);
276 return alg;
Adrian Bunk176c3652005-07-06 13:53:09 -0700277}
Herbert Xu492e2b62006-09-21 11:35:17 +1000278EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
Adrian Bunk176c3652005-07-06 13:53:09 -0700279
Herbert Xu27d2a332007-01-24 20:50:26 +1100280static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281{
Herbert Xu27d2a332007-01-24 20:50:26 +1100282 const struct crypto_type *type_obj = tfm->__crt_alg->cra_type;
Herbert Xue853c3c2006-08-22 00:06:54 +1000283
Herbert Xu27d2a332007-01-24 20:50:26 +1100284 if (type_obj)
285 return type_obj->init(tfm, type, mask);
Herbert Xue853c3c2006-08-22 00:06:54 +1000286
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 switch (crypto_tfm_alg_type(tfm)) {
288 case CRYPTO_ALG_TYPE_CIPHER:
289 return crypto_init_cipher_ops(tfm);
290
291 case CRYPTO_ALG_TYPE_DIGEST:
Loc Ho004a4032008-05-14 20:41:47 +0800292 if ((mask & CRYPTO_ALG_TYPE_HASH_MASK) !=
293 CRYPTO_ALG_TYPE_HASH_MASK)
294 return crypto_init_digest_ops_async(tfm);
295 else
296 return crypto_init_digest_ops(tfm);
297
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298 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{
Herbert Xue853c3c2006-08-22 00:06:54 +1000311 const struct crypto_type *type = tfm->__crt_alg->cra_type;
312
313 if (type) {
Herbert Xu4a779482008-09-13 18:19:03 -0700314 if (tfm->exit)
315 tfm->exit(tfm);
Herbert Xue853c3c2006-08-22 00:06:54 +1000316 return;
317 }
318
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319 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_DIGEST:
325 crypto_exit_digest_ops(tfm);
326 break;
327
328 case CRYPTO_ALG_TYPE_COMPRESS:
329 crypto_exit_compress_ops(tfm);
330 break;
331
332 default:
333 BUG();
334
335 }
336}
337
Herbert Xu27d2a332007-01-24 20:50:26 +1100338static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask)
Herbert Xufbdae9f2005-07-06 13:53:29 -0700339{
Herbert Xu27d2a332007-01-24 20:50:26 +1100340 const struct crypto_type *type_obj = alg->cra_type;
Herbert Xufbdae9f2005-07-06 13:53:29 -0700341 unsigned int len;
342
Herbert Xue853c3c2006-08-22 00:06:54 +1000343 len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1);
Herbert Xu27d2a332007-01-24 20:50:26 +1100344 if (type_obj)
345 return len + type_obj->ctxsize(alg, type, mask);
Herbert Xue853c3c2006-08-22 00:06:54 +1000346
Herbert Xufbdae9f2005-07-06 13:53:29 -0700347 switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
348 default:
349 BUG();
350
351 case CRYPTO_ALG_TYPE_CIPHER:
Herbert Xuf1ddcaf2007-01-27 10:05:15 +1100352 len += crypto_cipher_ctxsize(alg);
Herbert Xufbdae9f2005-07-06 13:53:29 -0700353 break;
354
355 case CRYPTO_ALG_TYPE_DIGEST:
Herbert Xuf1ddcaf2007-01-27 10:05:15 +1100356 len += crypto_digest_ctxsize(alg);
Herbert Xufbdae9f2005-07-06 13:53:29 -0700357 break;
358
359 case CRYPTO_ALG_TYPE_COMPRESS:
Herbert Xuf1ddcaf2007-01-27 10:05:15 +1100360 len += crypto_compress_ctxsize(alg);
Herbert Xufbdae9f2005-07-06 13:53:29 -0700361 break;
362 }
363
Herbert Xue853c3c2006-08-22 00:06:54 +1000364 return len;
Herbert Xufbdae9f2005-07-06 13:53:29 -0700365}
366
Herbert Xu6bfd4802006-09-21 11:39:29 +1000367void crypto_shoot_alg(struct crypto_alg *alg)
368{
369 down_write(&crypto_alg_sem);
370 alg->cra_flags |= CRYPTO_ALG_DYING;
371 up_write(&crypto_alg_sem);
372}
373EXPORT_SYMBOL_GPL(crypto_shoot_alg);
374
Herbert Xu27d2a332007-01-24 20:50:26 +1100375struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type,
376 u32 mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377{
378 struct crypto_tfm *tfm = NULL;
Herbert Xufbdae9f2005-07-06 13:53:29 -0700379 unsigned int tfm_size;
Herbert Xu6bfd4802006-09-21 11:39:29 +1000380 int err = -ENOMEM;
Herbert Xufbdae9f2005-07-06 13:53:29 -0700381
Herbert Xu27d2a332007-01-24 20:50:26 +1100382 tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
Eric Sesterhennbbeb5632006-03-06 21:42:07 +1100383 tfm = kzalloc(tfm_size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384 if (tfm == NULL)
Akinobu Mita9765d262006-10-11 22:29:51 +1000385 goto out_err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387 tfm->__crt_alg = alg;
Herbert Xu6bfd4802006-09-21 11:39:29 +1000388
Herbert Xu27d2a332007-01-24 20:50:26 +1100389 err = crypto_init_ops(tfm, type, mask);
Herbert Xu6bfd4802006-09-21 11:39:29 +1000390 if (err)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391 goto out_free_tfm;
Herbert Xuc7fc0592006-05-24 13:02:26 +1000392
Herbert Xu4a779482008-09-13 18:19:03 -0700393 if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
Herbert Xuc7fc0592006-05-24 13:02:26 +1000394 goto cra_init_failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395
396 goto out;
397
Herbert Xuc7fc0592006-05-24 13:02:26 +1000398cra_init_failed:
399 crypto_exit_ops(tfm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400out_free_tfm:
Herbert Xu4a779482008-09-13 18:19:03 -0700401 if (err == -EAGAIN)
402 crypto_shoot_alg(alg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 kfree(tfm);
Akinobu Mita9765d262006-10-11 22:29:51 +1000404out_err:
Herbert Xu6bfd4802006-09-21 11:39:29 +1000405 tfm = ERR_PTR(err);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700406out:
407 return tfm;
408}
Herbert Xu6bfd4802006-09-21 11:39:29 +1000409EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
410
Herbert Xu6d7d6842006-07-30 11:53:01 +1000411/*
412 * crypto_alloc_base - Locate algorithm and allocate transform
413 * @alg_name: Name of algorithm
414 * @type: Type of algorithm
415 * @mask: Mask for type comparison
416 *
Herbert Xu7b0bac62008-09-21 06:52:53 +0900417 * This function should not be used by new algorithm types.
418 * Plesae use crypto_alloc_tfm instead.
419 *
Herbert Xu6d7d6842006-07-30 11:53:01 +1000420 * crypto_alloc_base() will first attempt to locate an already loaded
421 * algorithm. If that fails and the kernel supports dynamically loadable
422 * modules, it will then attempt to load a module of the same name or
423 * alias. If that fails it will send a query to any loaded crypto manager
424 * to construct an algorithm on the fly. A refcount is grabbed on the
425 * algorithm which is then associated with the new transform.
426 *
427 * The returned transform is of a non-determinate type. Most people
428 * should use one of the more specific allocation functions such as
429 * crypto_alloc_blkcipher.
430 *
431 * In case of error the return value is an error pointer.
432 */
433struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
434{
435 struct crypto_tfm *tfm;
436 int err;
437
438 for (;;) {
439 struct crypto_alg *alg;
440
441 alg = crypto_alg_mod_lookup(alg_name, type, mask);
Akinobu Mita9765d262006-10-11 22:29:51 +1000442 if (IS_ERR(alg)) {
443 err = PTR_ERR(alg);
Herbert Xu6d7d6842006-07-30 11:53:01 +1000444 goto err;
Akinobu Mita9765d262006-10-11 22:29:51 +1000445 }
Herbert Xu6d7d6842006-07-30 11:53:01 +1000446
Herbert Xu27d2a332007-01-24 20:50:26 +1100447 tfm = __crypto_alloc_tfm(alg, type, mask);
Herbert Xu6d7d6842006-07-30 11:53:01 +1000448 if (!IS_ERR(tfm))
Akinobu Mita9765d262006-10-11 22:29:51 +1000449 return tfm;
Herbert Xu6d7d6842006-07-30 11:53:01 +1000450
451 crypto_mod_put(alg);
452 err = PTR_ERR(tfm);
453
454err:
455 if (err != -EAGAIN)
456 break;
457 if (signal_pending(current)) {
458 err = -EINTR;
459 break;
460 }
Akinobu Mita9765d262006-10-11 22:29:51 +1000461 }
Herbert Xu6d7d6842006-07-30 11:53:01 +1000462
Akinobu Mita9765d262006-10-11 22:29:51 +1000463 return ERR_PTR(err);
Herbert Xu6d7d6842006-07-30 11:53:01 +1000464}
465EXPORT_SYMBOL_GPL(crypto_alloc_base);
Herbert Xu7b0bac62008-09-21 06:52:53 +0900466
Herbert Xu3f683d62009-02-18 16:56:59 +0800467void *crypto_create_tfm(struct crypto_alg *alg,
468 const struct crypto_type *frontend)
Herbert Xu7b0bac62008-09-21 06:52:53 +0900469{
470 char *mem;
471 struct crypto_tfm *tfm = NULL;
472 unsigned int tfmsize;
473 unsigned int total;
474 int err = -ENOMEM;
475
476 tfmsize = frontend->tfmsize;
477 total = tfmsize + sizeof(*tfm) + frontend->extsize(alg, frontend);
478
479 mem = kzalloc(total, GFP_KERNEL);
480 if (mem == NULL)
481 goto out_err;
482
483 tfm = (struct crypto_tfm *)(mem + tfmsize);
484 tfm->__crt_alg = alg;
485
486 err = frontend->init_tfm(tfm, frontend);
487 if (err)
488 goto out_free_tfm;
489
490 if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
491 goto cra_init_failed;
492
493 goto out;
494
495cra_init_failed:
496 crypto_exit_ops(tfm);
497out_free_tfm:
498 if (err == -EAGAIN)
499 crypto_shoot_alg(alg);
500 kfree(mem);
501out_err:
Herbert Xu3f683d62009-02-18 16:56:59 +0800502 mem = ERR_PTR(err);
Herbert Xu7b0bac62008-09-21 06:52:53 +0900503out:
Herbert Xu3f683d62009-02-18 16:56:59 +0800504 return mem;
Herbert Xu7b0bac62008-09-21 06:52:53 +0900505}
506EXPORT_SYMBOL_GPL(crypto_create_tfm);
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 */
Herbert Xu3f683d62009-02-18 16:56:59 +0800528void *crypto_alloc_tfm(const char *alg_name,
529 const struct crypto_type *frontend, u32 type, u32 mask)
Herbert Xu7b0bac62008-09-21 06:52:53 +0900530{
531 struct crypto_alg *(*lookup)(const char *name, u32 type, u32 mask);
Herbert Xu3f683d62009-02-18 16:56:59 +0800532 void *tfm;
Herbert Xu7b0bac62008-09-21 06:52:53 +0900533 int err;
534
535 type &= frontend->maskclear;
536 mask &= frontend->maskclear;
537 type |= frontend->type;
538 mask |= frontend->maskset;
539
540 lookup = frontend->lookup ?: crypto_alg_mod_lookup;
541
542 for (;;) {
543 struct crypto_alg *alg;
544
545 alg = lookup(alg_name, type, mask);
546 if (IS_ERR(alg)) {
547 err = PTR_ERR(alg);
548 goto err;
549 }
550
551 tfm = crypto_create_tfm(alg, frontend);
552 if (!IS_ERR(tfm))
553 return tfm;
554
555 crypto_mod_put(alg);
556 err = PTR_ERR(tfm);
557
558err:
559 if (err != -EAGAIN)
560 break;
561 if (signal_pending(current)) {
562 err = -EINTR;
563 break;
564 }
565 }
566
567 return ERR_PTR(err);
568}
569EXPORT_SYMBOL_GPL(crypto_alloc_tfm);
Herbert Xu7b2cd922009-02-05 16:48:24 +1100570
Herbert Xu6d7d6842006-07-30 11:53:01 +1000571/*
Herbert Xu7b2cd922009-02-05 16:48:24 +1100572 * crypto_destroy_tfm - Free crypto transform
573 * @mem: Start of tfm slab
Herbert Xu6d7d6842006-07-30 11:53:01 +1000574 * @tfm: Transform to free
575 *
Herbert Xu7b2cd922009-02-05 16:48:24 +1100576 * This function frees up the transform and any associated resources,
Herbert Xu6d7d6842006-07-30 11:53:01 +1000577 * then drops the refcount on the associated algorithm.
578 */
Herbert Xu7b2cd922009-02-05 16:48:24 +1100579void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580{
Jesper Juhla61cc442005-07-06 13:54:31 -0700581 struct crypto_alg *alg;
582 int size;
583
Herbert Xu7b2cd922009-02-05 16:48:24 +1100584 if (unlikely(!mem))
Jesper Juhla61cc442005-07-06 13:54:31 -0700585 return;
586
587 alg = tfm->__crt_alg;
Herbert Xu7b2cd922009-02-05 16:48:24 +1100588 size = ksize(mem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589
Herbert Xu4a779482008-09-13 18:19:03 -0700590 if (!tfm->exit && alg->cra_exit)
Herbert Xuc7fc0592006-05-24 13:02:26 +1000591 alg->cra_exit(tfm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592 crypto_exit_ops(tfm);
Herbert Xu72fa4912006-05-28 09:05:24 +1000593 crypto_mod_put(alg);
Herbert Xu7b2cd922009-02-05 16:48:24 +1100594 memset(mem, 0, size);
595 kfree(mem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596}
Herbert Xu7b2cd922009-02-05 16:48:24 +1100597EXPORT_SYMBOL_GPL(crypto_destroy_tfm);
Herbert Xufce32d72006-08-26 17:35:45 +1000598
599int crypto_has_alg(const char *name, u32 type, u32 mask)
600{
601 int ret = 0;
602 struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
603
604 if (!IS_ERR(alg)) {
605 crypto_mod_put(alg);
606 ret = 1;
607 }
608
609 return ret;
610}
611EXPORT_SYMBOL_GPL(crypto_has_alg);
Sebastian Siewiorc3715cb92008-03-30 16:36:09 +0800612
613MODULE_DESCRIPTION("Cryptographic core API");
614MODULE_LICENSE("GPL");