ia64/linux-2.6.18-xen.hg

view crypto/api.c @ 854:950b9eb27661

usbback: fix urb interval value for interrupt urbs.

Signed-off-by: Noboru Iwamatsu <n_iwamatsu@jp.fujitsu.com>
author Keir Fraser <keir.fraser@citrix.com>
date Mon Apr 06 13:51:20 2009 +0100 (2009-04-06)
parents 831230e53067
children
line source
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 */
18 #include <linux/compiler.h>
19 #include <linux/init.h>
20 #include <linux/crypto.h>
21 #include <linux/errno.h>
22 #include <linux/kernel.h>
23 #include <linux/kmod.h>
24 #include <linux/rwsem.h>
25 #include <linux/slab.h>
26 #include <linux/string.h>
27 #include "internal.h"
29 LIST_HEAD(crypto_alg_list);
30 DECLARE_RWSEM(crypto_alg_sem);
32 static inline int crypto_alg_get(struct crypto_alg *alg)
33 {
34 return try_module_get(alg->cra_module);
35 }
37 static inline void crypto_alg_put(struct crypto_alg *alg)
38 {
39 module_put(alg->cra_module);
40 }
42 static struct crypto_alg *crypto_alg_lookup(const char *name)
43 {
44 struct crypto_alg *q, *alg = NULL;
45 int best = -1;
47 if (!name)
48 return NULL;
50 down_read(&crypto_alg_sem);
52 list_for_each_entry(q, &crypto_alg_list, cra_list) {
53 int exact, fuzzy;
55 exact = !strcmp(q->cra_driver_name, name);
56 fuzzy = !strcmp(q->cra_name, name);
57 if (!exact && !(fuzzy && q->cra_priority > best))
58 continue;
60 if (unlikely(!crypto_alg_get(q)))
61 continue;
63 best = q->cra_priority;
64 if (alg)
65 crypto_alg_put(alg);
66 alg = q;
68 if (exact)
69 break;
70 }
72 up_read(&crypto_alg_sem);
73 return alg;
74 }
76 /* A far more intelligent version of this is planned. For now, just
77 * try an exact match on the name of the algorithm. */
78 static inline struct crypto_alg *crypto_alg_mod_lookup(const char *name)
79 {
80 return try_then_request_module(crypto_alg_lookup(name), name);
81 }
83 static int crypto_init_flags(struct crypto_tfm *tfm, u32 flags)
84 {
85 tfm->crt_flags = flags & CRYPTO_TFM_REQ_MASK;
86 flags &= ~CRYPTO_TFM_REQ_MASK;
88 switch (crypto_tfm_alg_type(tfm)) {
89 case CRYPTO_ALG_TYPE_CIPHER:
90 return crypto_init_cipher_flags(tfm, flags);
92 case CRYPTO_ALG_TYPE_DIGEST:
93 return crypto_init_digest_flags(tfm, flags);
95 case CRYPTO_ALG_TYPE_COMPRESS:
96 return crypto_init_compress_flags(tfm, flags);
98 default:
99 break;
100 }
102 BUG();
103 return -EINVAL;
104 }
106 static int crypto_init_ops(struct crypto_tfm *tfm)
107 {
108 switch (crypto_tfm_alg_type(tfm)) {
109 case CRYPTO_ALG_TYPE_CIPHER:
110 return crypto_init_cipher_ops(tfm);
112 case CRYPTO_ALG_TYPE_DIGEST:
113 return crypto_init_digest_ops(tfm);
115 case CRYPTO_ALG_TYPE_COMPRESS:
116 return crypto_init_compress_ops(tfm);
118 default:
119 break;
120 }
122 BUG();
123 return -EINVAL;
124 }
126 static void crypto_exit_ops(struct crypto_tfm *tfm)
127 {
128 switch (crypto_tfm_alg_type(tfm)) {
129 case CRYPTO_ALG_TYPE_CIPHER:
130 crypto_exit_cipher_ops(tfm);
131 break;
133 case CRYPTO_ALG_TYPE_DIGEST:
134 crypto_exit_digest_ops(tfm);
135 break;
137 case CRYPTO_ALG_TYPE_COMPRESS:
138 crypto_exit_compress_ops(tfm);
139 break;
141 default:
142 BUG();
144 }
145 }
147 static unsigned int crypto_ctxsize(struct crypto_alg *alg, int flags)
148 {
149 unsigned int len;
151 switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
152 default:
153 BUG();
155 case CRYPTO_ALG_TYPE_CIPHER:
156 len = crypto_cipher_ctxsize(alg, flags);
157 break;
159 case CRYPTO_ALG_TYPE_DIGEST:
160 len = crypto_digest_ctxsize(alg, flags);
161 break;
163 case CRYPTO_ALG_TYPE_COMPRESS:
164 len = crypto_compress_ctxsize(alg, flags);
165 break;
166 }
168 return len + (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));
169 }
171 struct crypto_tfm *crypto_alloc_tfm(const char *name, u32 flags)
172 {
173 struct crypto_tfm *tfm = NULL;
174 struct crypto_alg *alg;
175 unsigned int tfm_size;
177 alg = crypto_alg_mod_lookup(name);
178 if (alg == NULL)
179 goto out;
181 tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, flags);
182 tfm = kzalloc(tfm_size, GFP_KERNEL);
183 if (tfm == NULL)
184 goto out_put;
186 tfm->__crt_alg = alg;
188 if (crypto_init_flags(tfm, flags))
189 goto out_free_tfm;
191 if (crypto_init_ops(tfm))
192 goto out_free_tfm;
194 if (alg->cra_init && alg->cra_init(tfm))
195 goto cra_init_failed;
197 goto out;
199 cra_init_failed:
200 crypto_exit_ops(tfm);
201 out_free_tfm:
202 kfree(tfm);
203 tfm = NULL;
204 out_put:
205 crypto_alg_put(alg);
206 out:
207 return tfm;
208 }
210 void crypto_free_tfm(struct crypto_tfm *tfm)
211 {
212 struct crypto_alg *alg;
213 int size;
215 if (unlikely(!tfm))
216 return;
218 alg = tfm->__crt_alg;
219 size = sizeof(*tfm) + alg->cra_ctxsize;
221 if (alg->cra_exit)
222 alg->cra_exit(tfm);
223 crypto_exit_ops(tfm);
224 crypto_alg_put(alg);
225 memset(tfm, 0, size);
226 kfree(tfm);
227 }
229 static inline int crypto_set_driver_name(struct crypto_alg *alg)
230 {
231 static const char suffix[] = "-generic";
232 char *driver_name = alg->cra_driver_name;
233 int len;
235 if (*driver_name)
236 return 0;
238 len = strlcpy(driver_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
239 if (len + sizeof(suffix) > CRYPTO_MAX_ALG_NAME)
240 return -ENAMETOOLONG;
242 memcpy(driver_name + len, suffix, sizeof(suffix));
243 return 0;
244 }
246 int crypto_register_alg(struct crypto_alg *alg)
247 {
248 int ret;
249 struct crypto_alg *q;
251 if (alg->cra_alignmask & (alg->cra_alignmask + 1))
252 return -EINVAL;
254 if (alg->cra_alignmask & alg->cra_blocksize)
255 return -EINVAL;
257 if (alg->cra_blocksize > PAGE_SIZE / 8)
258 return -EINVAL;
260 if (alg->cra_priority < 0)
261 return -EINVAL;
263 ret = crypto_set_driver_name(alg);
264 if (unlikely(ret))
265 return ret;
267 down_write(&crypto_alg_sem);
269 list_for_each_entry(q, &crypto_alg_list, cra_list) {
270 if (q == alg) {
271 ret = -EEXIST;
272 goto out;
273 }
274 }
276 list_add(&alg->cra_list, &crypto_alg_list);
277 out:
278 up_write(&crypto_alg_sem);
279 return ret;
280 }
282 int crypto_unregister_alg(struct crypto_alg *alg)
283 {
284 int ret = -ENOENT;
285 struct crypto_alg *q;
287 BUG_ON(!alg->cra_module);
289 down_write(&crypto_alg_sem);
290 list_for_each_entry(q, &crypto_alg_list, cra_list) {
291 if (alg == q) {
292 list_del(&alg->cra_list);
293 ret = 0;
294 goto out;
295 }
296 }
297 out:
298 up_write(&crypto_alg_sem);
299 return ret;
300 }
302 int crypto_alg_available(const char *name, u32 flags)
303 {
304 int ret = 0;
305 struct crypto_alg *alg = crypto_alg_mod_lookup(name);
307 if (alg) {
308 crypto_alg_put(alg);
309 ret = 1;
310 }
312 return ret;
313 }
315 static int __init init_crypto(void)
316 {
317 printk(KERN_INFO "Initializing Cryptographic API\n");
318 crypto_init_proc();
319 return 0;
320 }
322 __initcall(init_crypto);
324 EXPORT_SYMBOL_GPL(crypto_register_alg);
325 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
326 EXPORT_SYMBOL_GPL(crypto_alloc_tfm);
327 EXPORT_SYMBOL_GPL(crypto_free_tfm);
328 EXPORT_SYMBOL_GPL(crypto_alg_available);