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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
58struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type, u32 mask)
59{
60 struct crypto_alg *q, *alg = NULL;
61 int best = -2;
62
63 list_for_each_entry(q, &crypto_alg_list, cra_list) {
64 int exact, fuzzy;
65
66 if (crypto_is_moribund(q))
67 continue;
68
69 if ((q->cra_flags ^ type) & mask)
70 continue;
71
72 if (crypto_is_larval(q) &&
73 ((struct crypto_larval *)q)->mask != mask)
74 continue;
75
76 exact = !strcmp(q->cra_driver_name, name);
77 fuzzy = !strcmp(q->cra_name, name);
78 if (!exact && !(fuzzy && q->cra_priority > best))
79 continue;
80
81 if (unlikely(!crypto_mod_get(q)))
82 continue;
83
84 best = q->cra_priority;
85 if (alg)
86 crypto_mod_put(alg);
87 alg = q;
88
89 if (exact)
90 break;
91 }
92
93 return alg;
94}
95EXPORT_SYMBOL_GPL(__crypto_alg_lookup);
96
97static 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
107static struct crypto_alg *crypto_larval_alloc(const char *name, u32 type,
108 u32 mask)
109{
110 struct crypto_alg *alg;
111 struct crypto_larval *larval;
112
113 larval = kzalloc(sizeof(*larval), GFP_KERNEL);
114 if (!larval)
115 return ERR_PTR(-ENOMEM);
116
117 larval->mask = mask;
118 larval->alg.cra_flags = CRYPTO_ALG_LARVAL | type;
119 larval->alg.cra_priority = -1;
120 larval->alg.cra_destroy = crypto_larval_destroy;
121
122 atomic_set(&larval->alg.cra_refcnt, 2);
123 strlcpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME);
124 init_completion(&larval->completion);
125
126 down_write(&crypto_alg_sem);
127 alg = __crypto_alg_lookup(name, type, mask);
128 if (!alg) {
129 alg = &larval->alg;
130 list_add(&alg->cra_list, &crypto_alg_list);
131 }
132 up_write(&crypto_alg_sem);
133
134 if (alg != &larval->alg)
135 kfree(larval);
136
137 return alg;
138}
139
140void crypto_larval_kill(struct crypto_alg *alg)
141{
142 struct crypto_larval *larval = (void *)alg;
143
144 down_write(&crypto_alg_sem);
145 list_del(&alg->cra_list);
146 up_write(&crypto_alg_sem);
147 complete_all(&larval->completion);
148 crypto_alg_put(alg);
149}
150EXPORT_SYMBOL_GPL(crypto_larval_kill);
151
152static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg)
153{
154 struct crypto_larval *larval = (void *)alg;
155
156 wait_for_completion_interruptible_timeout(&larval->completion, 60 * HZ);
157 alg = larval->adult;
158 if (alg) {
159 if (!crypto_mod_get(alg))
160 alg = ERR_PTR(-EAGAIN);
161 } else
162 alg = ERR_PTR(-ENOENT);
163 crypto_mod_put(&larval->alg);
164
165 return alg;
166}
167
168static struct crypto_alg *crypto_alg_lookup(const char *name, u32 type,
169 u32 mask)
170{
171 struct crypto_alg *alg;
172
173 down_read(&crypto_alg_sem);
174 alg = __crypto_alg_lookup(name, type, mask);
175 up_read(&crypto_alg_sem);
176
177 return alg;
178}
179
180struct crypto_alg *crypto_larval_lookup(const char *name, u32 type, u32 mask)
181{
182 struct crypto_alg *alg;
183
184 if (!name)
185 return ERR_PTR(-ENOENT);
186
187 mask &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
188 type &= mask;
189
190 alg = try_then_request_module(crypto_alg_lookup(name, type, mask),
191 name);
192 if (alg)
193 return crypto_is_larval(alg) ? crypto_larval_wait(alg) : alg;
194
195 return crypto_larval_alloc(name, type, mask);
196}
197EXPORT_SYMBOL_GPL(crypto_larval_lookup);
198
199struct crypto_alg *crypto_alg_mod_lookup(const char *name, u32 type, u32 mask)
200{
201 struct crypto_alg *alg;
202 struct crypto_alg *larval;
203 int ok;
204
205 larval = crypto_larval_lookup(name, type, mask);
206 if (IS_ERR(larval) || !crypto_is_larval(larval))
207 return larval;
208
209 ok = crypto_notify(CRYPTO_MSG_ALG_REQUEST, larval);
210 if (ok == NOTIFY_DONE) {
211 request_module("cryptomgr");
212 ok = crypto_notify(CRYPTO_MSG_ALG_REQUEST, larval);
213 }
214
215 if (ok == NOTIFY_STOP)
216 alg = crypto_larval_wait(larval);
217 else {
218 crypto_mod_put(larval);
219 alg = ERR_PTR(-ENOENT);
220 }
221 crypto_larval_kill(larval);
222 return alg;
223}
224EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
225
226static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
227{
228 const struct crypto_type *type_obj = tfm->__crt_alg->cra_type;
229
230 if (type_obj)
231 return type_obj->init(tfm, type, mask);
232
233 switch (crypto_tfm_alg_type(tfm)) {
234 case CRYPTO_ALG_TYPE_CIPHER:
235 return crypto_init_cipher_ops(tfm);
236
237 case CRYPTO_ALG_TYPE_DIGEST:
238 if ((mask & CRYPTO_ALG_TYPE_HASH_MASK) !=
239 CRYPTO_ALG_TYPE_HASH_MASK)
240 return crypto_init_digest_ops_async(tfm);
241 else
242 return crypto_init_digest_ops(tfm);
243
244 case CRYPTO_ALG_TYPE_COMPRESS:
245 return crypto_init_compress_ops(tfm);
246
247 default:
248 break;
249 }
250
251 BUG();
252 return -EINVAL;
253}
254
255static void crypto_exit_ops(struct crypto_tfm *tfm)
256{
257 const struct crypto_type *type = tfm->__crt_alg->cra_type;
258
259 if (type) {
260 if (type->exit)
261 type->exit(tfm);
262 return;
263 }
264
265 switch (crypto_tfm_alg_type(tfm)) {
266 case CRYPTO_ALG_TYPE_CIPHER:
267 crypto_exit_cipher_ops(tfm);
268 break;
269
270 case CRYPTO_ALG_TYPE_DIGEST:
271 crypto_exit_digest_ops(tfm);
272 break;
273
274 case CRYPTO_ALG_TYPE_COMPRESS:
275 crypto_exit_compress_ops(tfm);
276 break;
277
278 default:
279 BUG();
280
281 }
282}
283
284static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask)
285{
286 const struct crypto_type *type_obj = alg->cra_type;
287 unsigned int len;
288
289 len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1);
290 if (type_obj)
291 return len + type_obj->ctxsize(alg, type, mask);
292
293 switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
294 default:
295 BUG();
296
297 case CRYPTO_ALG_TYPE_CIPHER:
298 len += crypto_cipher_ctxsize(alg);
299 break;
300
301 case CRYPTO_ALG_TYPE_DIGEST:
302 len += crypto_digest_ctxsize(alg);
303 break;
304
305 case CRYPTO_ALG_TYPE_COMPRESS:
306 len += crypto_compress_ctxsize(alg);
307 break;
308 }
309
310 return len;
311}
312
313void crypto_shoot_alg(struct crypto_alg *alg)
314{
315 down_write(&crypto_alg_sem);
316 alg->cra_flags |= CRYPTO_ALG_DYING;
317 up_write(&crypto_alg_sem);
318}
319EXPORT_SYMBOL_GPL(crypto_shoot_alg);
320
321struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type,
322 u32 mask)
323{
324 struct crypto_tfm *tfm = NULL;
325 unsigned int tfm_size;
326 int err = -ENOMEM;
327
328 tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
329 tfm = kzalloc(tfm_size, GFP_KERNEL);
330 if (tfm == NULL)
331 goto out_err;
332
333 tfm->__crt_alg = alg;
334
335 err = crypto_init_ops(tfm, type, mask);
336 if (err)
337 goto out_free_tfm;
338
339 if (alg->cra_init && (err = alg->cra_init(tfm))) {
340 if (err == -EAGAIN)
341 crypto_shoot_alg(alg);
342 goto cra_init_failed;
343 }
344
345 goto out;
346
347cra_init_failed:
348 crypto_exit_ops(tfm);
349out_free_tfm:
350 kfree(tfm);
351out_err:
352 tfm = ERR_PTR(err);
353out:
354 return tfm;
355}
356EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
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377struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
378{
379 struct crypto_tfm *tfm;
380 int err;
381
382 for (;;) {
383 struct crypto_alg *alg;
384
385 alg = crypto_alg_mod_lookup(alg_name, type, mask);
386 if (IS_ERR(alg)) {
387 err = PTR_ERR(alg);
388 goto err;
389 }
390
391 tfm = __crypto_alloc_tfm(alg, type, mask);
392 if (!IS_ERR(tfm))
393 return tfm;
394
395 crypto_mod_put(alg);
396 err = PTR_ERR(tfm);
397
398err:
399 if (err != -EAGAIN)
400 break;
401 if (signal_pending(current)) {
402 err = -EINTR;
403 break;
404 }
405 }
406
407 return ERR_PTR(err);
408}
409EXPORT_SYMBOL_GPL(crypto_alloc_base);
410
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416
417
418void crypto_free_tfm(struct crypto_tfm *tfm)
419{
420 struct crypto_alg *alg;
421 int size;
422
423 if (unlikely(!tfm))
424 return;
425
426 alg = tfm->__crt_alg;
427 size = sizeof(*tfm) + alg->cra_ctxsize;
428
429 if (alg->cra_exit)
430 alg->cra_exit(tfm);
431 crypto_exit_ops(tfm);
432 crypto_mod_put(alg);
433 memset(tfm, 0, size);
434 kfree(tfm);
435}
436
437EXPORT_SYMBOL_GPL(crypto_free_tfm);
438
439int crypto_has_alg(const char *name, u32 type, u32 mask)
440{
441 int ret = 0;
442 struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
443
444 if (!IS_ERR(alg)) {
445 crypto_mod_put(alg);
446 ret = 1;
447 }
448
449 return ret;
450}
451EXPORT_SYMBOL_GPL(crypto_has_alg);
452
453MODULE_DESCRIPTION("Cryptographic core API");
454MODULE_LICENSE("GPL");
455
