Commit | Line | Data |
---|---|---|
03c8efc1 HX |
1 | /* |
2 | * af_alg: User-space algorithm interface | |
3 | * | |
4 | * This file provides the user-space API for algorithms. | |
5 | * | |
6 | * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au> | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify it | |
9 | * under the terms of the GNU General Public License as published by the Free | |
10 | * Software Foundation; either version 2 of the License, or (at your option) | |
11 | * any later version. | |
12 | * | |
13 | */ | |
14 | ||
60063497 | 15 | #include <linux/atomic.h> |
03c8efc1 HX |
16 | #include <crypto/if_alg.h> |
17 | #include <linux/crypto.h> | |
18 | #include <linux/init.h> | |
19 | #include <linux/kernel.h> | |
20 | #include <linux/list.h> | |
21 | #include <linux/module.h> | |
22 | #include <linux/net.h> | |
23 | #include <linux/rwsem.h> | |
4a6d0c80 | 24 | #include <linux/security.h> |
03c8efc1 HX |
25 | |
26 | struct alg_type_list { | |
27 | const struct af_alg_type *type; | |
28 | struct list_head list; | |
29 | }; | |
30 | ||
06869524 | 31 | static atomic_long_t alg_memory_allocated; |
03c8efc1 HX |
32 | |
33 | static struct proto alg_proto = { | |
34 | .name = "ALG", | |
35 | .owner = THIS_MODULE, | |
36 | .memory_allocated = &alg_memory_allocated, | |
37 | .obj_size = sizeof(struct alg_sock), | |
38 | }; | |
39 | ||
40 | static LIST_HEAD(alg_types); | |
41 | static DECLARE_RWSEM(alg_types_sem); | |
42 | ||
43 | static const struct af_alg_type *alg_get_type(const char *name) | |
44 | { | |
45 | const struct af_alg_type *type = ERR_PTR(-ENOENT); | |
46 | struct alg_type_list *node; | |
47 | ||
48 | down_read(&alg_types_sem); | |
49 | list_for_each_entry(node, &alg_types, list) { | |
50 | if (strcmp(node->type->name, name)) | |
51 | continue; | |
52 | ||
53 | if (try_module_get(node->type->owner)) | |
54 | type = node->type; | |
55 | break; | |
56 | } | |
57 | up_read(&alg_types_sem); | |
58 | ||
59 | return type; | |
60 | } | |
61 | ||
62 | int af_alg_register_type(const struct af_alg_type *type) | |
63 | { | |
64 | struct alg_type_list *node; | |
65 | int err = -EEXIST; | |
66 | ||
67 | down_write(&alg_types_sem); | |
68 | list_for_each_entry(node, &alg_types, list) { | |
69 | if (!strcmp(node->type->name, type->name)) | |
70 | goto unlock; | |
71 | } | |
72 | ||
73 | node = kmalloc(sizeof(*node), GFP_KERNEL); | |
74 | err = -ENOMEM; | |
75 | if (!node) | |
76 | goto unlock; | |
77 | ||
78 | type->ops->owner = THIS_MODULE; | |
a37d0897 HX |
79 | if (type->ops_nokey) |
80 | type->ops_nokey->owner = THIS_MODULE; | |
03c8efc1 HX |
81 | node->type = type; |
82 | list_add(&node->list, &alg_types); | |
83 | err = 0; | |
84 | ||
85 | unlock: | |
86 | up_write(&alg_types_sem); | |
87 | ||
88 | return err; | |
89 | } | |
90 | EXPORT_SYMBOL_GPL(af_alg_register_type); | |
91 | ||
92 | int af_alg_unregister_type(const struct af_alg_type *type) | |
93 | { | |
94 | struct alg_type_list *node; | |
95 | int err = -ENOENT; | |
96 | ||
97 | down_write(&alg_types_sem); | |
98 | list_for_each_entry(node, &alg_types, list) { | |
99 | if (strcmp(node->type->name, type->name)) | |
100 | continue; | |
101 | ||
102 | list_del(&node->list); | |
103 | kfree(node); | |
104 | err = 0; | |
105 | break; | |
106 | } | |
107 | up_write(&alg_types_sem); | |
108 | ||
109 | return err; | |
110 | } | |
111 | EXPORT_SYMBOL_GPL(af_alg_unregister_type); | |
112 | ||
113 | static void alg_do_release(const struct af_alg_type *type, void *private) | |
114 | { | |
115 | if (!type) | |
116 | return; | |
117 | ||
118 | type->release(private); | |
119 | module_put(type->owner); | |
120 | } | |
121 | ||
122 | int af_alg_release(struct socket *sock) | |
123 | { | |
124 | if (sock->sk) | |
125 | sock_put(sock->sk); | |
126 | return 0; | |
127 | } | |
128 | EXPORT_SYMBOL_GPL(af_alg_release); | |
129 | ||
12514d46 HX |
130 | void af_alg_release_parent(struct sock *sk) |
131 | { | |
132 | struct alg_sock *ask = alg_sk(sk); | |
fb0b50cf HX |
133 | unsigned int nokey = ask->nokey_refcnt; |
134 | bool last = nokey && !ask->refcnt; | |
12514d46 HX |
135 | |
136 | sk = ask->parent; | |
137 | ask = alg_sk(sk); | |
138 | ||
139 | lock_sock(sk); | |
fb0b50cf HX |
140 | ask->nokey_refcnt -= nokey; |
141 | if (!last) | |
142 | last = !--ask->refcnt; | |
12514d46 HX |
143 | release_sock(sk); |
144 | ||
145 | if (last) | |
146 | sock_put(sk); | |
147 | } | |
148 | EXPORT_SYMBOL_GPL(af_alg_release_parent); | |
149 | ||
03c8efc1 HX |
150 | static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) |
151 | { | |
152 | struct sock *sk = sock->sk; | |
153 | struct alg_sock *ask = alg_sk(sk); | |
154 | struct sockaddr_alg *sa = (void *)uaddr; | |
155 | const struct af_alg_type *type; | |
156 | void *private; | |
12514d46 | 157 | int err; |
03c8efc1 HX |
158 | |
159 | if (sock->state == SS_CONNECTED) | |
160 | return -EINVAL; | |
161 | ||
162 | if (addr_len != sizeof(*sa)) | |
163 | return -EINVAL; | |
164 | ||
165 | sa->salg_type[sizeof(sa->salg_type) - 1] = 0; | |
166 | sa->salg_name[sizeof(sa->salg_name) - 1] = 0; | |
167 | ||
168 | type = alg_get_type(sa->salg_type); | |
169 | if (IS_ERR(type) && PTR_ERR(type) == -ENOENT) { | |
170 | request_module("algif-%s", sa->salg_type); | |
171 | type = alg_get_type(sa->salg_type); | |
172 | } | |
173 | ||
174 | if (IS_ERR(type)) | |
175 | return PTR_ERR(type); | |
176 | ||
177 | private = type->bind(sa->salg_name, sa->salg_feat, sa->salg_mask); | |
178 | if (IS_ERR(private)) { | |
179 | module_put(type->owner); | |
180 | return PTR_ERR(private); | |
181 | } | |
182 | ||
12514d46 | 183 | err = -EBUSY; |
03c8efc1 | 184 | lock_sock(sk); |
fb0b50cf | 185 | if (ask->refcnt | ask->nokey_refcnt) |
12514d46 | 186 | goto unlock; |
03c8efc1 HX |
187 | |
188 | swap(ask->type, type); | |
189 | swap(ask->private, private); | |
190 | ||
12514d46 HX |
191 | err = 0; |
192 | ||
193 | unlock: | |
03c8efc1 HX |
194 | release_sock(sk); |
195 | ||
196 | alg_do_release(type, private); | |
197 | ||
12514d46 | 198 | return err; |
03c8efc1 HX |
199 | } |
200 | ||
201 | static int alg_setkey(struct sock *sk, char __user *ukey, | |
202 | unsigned int keylen) | |
203 | { | |
204 | struct alg_sock *ask = alg_sk(sk); | |
205 | const struct af_alg_type *type = ask->type; | |
206 | u8 *key; | |
207 | int err; | |
208 | ||
209 | key = sock_kmalloc(sk, keylen, GFP_KERNEL); | |
210 | if (!key) | |
211 | return -ENOMEM; | |
212 | ||
213 | err = -EFAULT; | |
214 | if (copy_from_user(key, ukey, keylen)) | |
215 | goto out; | |
216 | ||
217 | err = type->setkey(ask->private, key, keylen); | |
218 | ||
219 | out: | |
220 | sock_kfree_s(sk, key, keylen); | |
221 | ||
222 | return err; | |
223 | } | |
224 | ||
225 | static int alg_setsockopt(struct socket *sock, int level, int optname, | |
226 | char __user *optval, unsigned int optlen) | |
227 | { | |
228 | struct sock *sk = sock->sk; | |
229 | struct alg_sock *ask = alg_sk(sk); | |
230 | const struct af_alg_type *type; | |
12514d46 | 231 | int err = -EBUSY; |
03c8efc1 HX |
232 | |
233 | lock_sock(sk); | |
12514d46 HX |
234 | if (ask->refcnt) |
235 | goto unlock; | |
236 | ||
03c8efc1 HX |
237 | type = ask->type; |
238 | ||
12514d46 | 239 | err = -ENOPROTOOPT; |
03c8efc1 HX |
240 | if (level != SOL_ALG || !type) |
241 | goto unlock; | |
242 | ||
243 | switch (optname) { | |
244 | case ALG_SET_KEY: | |
245 | if (sock->state == SS_CONNECTED) | |
246 | goto unlock; | |
247 | if (!type->setkey) | |
248 | goto unlock; | |
249 | ||
250 | err = alg_setkey(sk, optval, optlen); | |
251 | } | |
252 | ||
253 | unlock: | |
254 | release_sock(sk); | |
255 | ||
256 | return err; | |
257 | } | |
258 | ||
259 | int af_alg_accept(struct sock *sk, struct socket *newsock) | |
260 | { | |
261 | struct alg_sock *ask = alg_sk(sk); | |
262 | const struct af_alg_type *type; | |
263 | struct sock *sk2; | |
61d05831 | 264 | unsigned int nokey; |
03c8efc1 HX |
265 | int err; |
266 | ||
267 | lock_sock(sk); | |
268 | type = ask->type; | |
269 | ||
270 | err = -EINVAL; | |
271 | if (!type) | |
272 | goto unlock; | |
273 | ||
274 | sk2 = sk_alloc(sock_net(sk), PF_ALG, GFP_KERNEL, &alg_proto); | |
275 | err = -ENOMEM; | |
276 | if (!sk2) | |
277 | goto unlock; | |
278 | ||
279 | sock_init_data(newsock, sk2); | |
507cad35 | 280 | sock_graft(sk2, newsock); |
4a6d0c80 | 281 | security_sk_clone(sk, sk2); |
03c8efc1 HX |
282 | |
283 | err = type->accept(ask->private, sk2); | |
a37d0897 HX |
284 | |
285 | nokey = err == -ENOKEY; | |
286 | if (nokey && type->accept_nokey) | |
287 | err = type->accept_nokey(ask->private, sk2); | |
288 | ||
f77597b2 | 289 | if (err) |
03c8efc1 | 290 | goto unlock; |
03c8efc1 HX |
291 | |
292 | sk2->sk_family = PF_ALG; | |
293 | ||
a37d0897 | 294 | if (nokey || !ask->refcnt++) |
12514d46 | 295 | sock_hold(sk); |
fb0b50cf | 296 | ask->nokey_refcnt += nokey; |
03c8efc1 HX |
297 | alg_sk(sk2)->parent = sk; |
298 | alg_sk(sk2)->type = type; | |
61d05831 | 299 | alg_sk(sk2)->nokey_refcnt = nokey; |
03c8efc1 HX |
300 | |
301 | newsock->ops = type->ops; | |
302 | newsock->state = SS_CONNECTED; | |
303 | ||
a37d0897 HX |
304 | if (nokey) |
305 | newsock->ops = type->ops_nokey; | |
306 | ||
03c8efc1 HX |
307 | err = 0; |
308 | ||
309 | unlock: | |
310 | release_sock(sk); | |
311 | ||
312 | return err; | |
313 | } | |
314 | EXPORT_SYMBOL_GPL(af_alg_accept); | |
315 | ||
316 | static int alg_accept(struct socket *sock, struct socket *newsock, int flags) | |
317 | { | |
318 | return af_alg_accept(sock->sk, newsock); | |
319 | } | |
320 | ||
321 | static const struct proto_ops alg_proto_ops = { | |
322 | .family = PF_ALG, | |
323 | .owner = THIS_MODULE, | |
324 | ||
325 | .connect = sock_no_connect, | |
326 | .socketpair = sock_no_socketpair, | |
327 | .getname = sock_no_getname, | |
328 | .ioctl = sock_no_ioctl, | |
329 | .listen = sock_no_listen, | |
330 | .shutdown = sock_no_shutdown, | |
331 | .getsockopt = sock_no_getsockopt, | |
332 | .mmap = sock_no_mmap, | |
333 | .sendpage = sock_no_sendpage, | |
334 | .sendmsg = sock_no_sendmsg, | |
335 | .recvmsg = sock_no_recvmsg, | |
336 | .poll = sock_no_poll, | |
337 | ||
338 | .bind = alg_bind, | |
339 | .release = af_alg_release, | |
340 | .setsockopt = alg_setsockopt, | |
341 | .accept = alg_accept, | |
342 | }; | |
343 | ||
344 | static void alg_sock_destruct(struct sock *sk) | |
345 | { | |
346 | struct alg_sock *ask = alg_sk(sk); | |
347 | ||
348 | alg_do_release(ask->type, ask->private); | |
349 | } | |
350 | ||
351 | static int alg_create(struct net *net, struct socket *sock, int protocol, | |
352 | int kern) | |
353 | { | |
354 | struct sock *sk; | |
355 | int err; | |
356 | ||
357 | if (sock->type != SOCK_SEQPACKET) | |
358 | return -ESOCKTNOSUPPORT; | |
359 | if (protocol != 0) | |
360 | return -EPROTONOSUPPORT; | |
361 | ||
362 | err = -ENOMEM; | |
363 | sk = sk_alloc(net, PF_ALG, GFP_KERNEL, &alg_proto); | |
364 | if (!sk) | |
365 | goto out; | |
366 | ||
367 | sock->ops = &alg_proto_ops; | |
368 | sock_init_data(sock, sk); | |
369 | ||
370 | sk->sk_family = PF_ALG; | |
371 | sk->sk_destruct = alg_sock_destruct; | |
372 | ||
373 | return 0; | |
374 | out: | |
375 | return err; | |
376 | } | |
377 | ||
378 | static const struct net_proto_family alg_family = { | |
379 | .family = PF_ALG, | |
380 | .create = alg_create, | |
381 | .owner = THIS_MODULE, | |
382 | }; | |
383 | ||
384 | int af_alg_make_sg(struct af_alg_sgl *sgl, void __user *addr, int len, | |
385 | int write) | |
386 | { | |
387 | unsigned long from = (unsigned long)addr; | |
388 | unsigned long npages; | |
389 | unsigned off; | |
390 | int err; | |
391 | int i; | |
392 | ||
393 | err = -EFAULT; | |
394 | if (!access_ok(write ? VERIFY_READ : VERIFY_WRITE, addr, len)) | |
395 | goto out; | |
396 | ||
397 | off = from & ~PAGE_MASK; | |
398 | npages = (off + len + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
399 | if (npages > ALG_MAX_PAGES) | |
400 | npages = ALG_MAX_PAGES; | |
401 | ||
402 | err = get_user_pages_fast(from, npages, write, sgl->pages); | |
403 | if (err < 0) | |
404 | goto out; | |
405 | ||
406 | npages = err; | |
407 | err = -EINVAL; | |
408 | if (WARN_ON(npages == 0)) | |
409 | goto out; | |
410 | ||
411 | err = 0; | |
412 | ||
413 | sg_init_table(sgl->sg, npages); | |
414 | ||
415 | for (i = 0; i < npages; i++) { | |
416 | int plen = min_t(int, len, PAGE_SIZE - off); | |
417 | ||
418 | sg_set_page(sgl->sg + i, sgl->pages[i], plen, off); | |
419 | ||
420 | off = 0; | |
421 | len -= plen; | |
422 | err += plen; | |
423 | } | |
424 | ||
425 | out: | |
426 | return err; | |
427 | } | |
428 | EXPORT_SYMBOL_GPL(af_alg_make_sg); | |
429 | ||
430 | void af_alg_free_sg(struct af_alg_sgl *sgl) | |
431 | { | |
432 | int i; | |
433 | ||
434 | i = 0; | |
435 | do { | |
436 | put_page(sgl->pages[i]); | |
437 | } while (!sg_is_last(sgl->sg + (i++))); | |
438 | } | |
439 | EXPORT_SYMBOL_GPL(af_alg_free_sg); | |
440 | ||
441 | int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con) | |
442 | { | |
443 | struct cmsghdr *cmsg; | |
444 | ||
445 | for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) { | |
446 | if (!CMSG_OK(msg, cmsg)) | |
447 | return -EINVAL; | |
448 | if (cmsg->cmsg_level != SOL_ALG) | |
449 | continue; | |
450 | ||
451 | switch(cmsg->cmsg_type) { | |
452 | case ALG_SET_IV: | |
453 | if (cmsg->cmsg_len < CMSG_LEN(sizeof(*con->iv))) | |
454 | return -EINVAL; | |
455 | con->iv = (void *)CMSG_DATA(cmsg); | |
456 | if (cmsg->cmsg_len < CMSG_LEN(con->iv->ivlen + | |
457 | sizeof(*con->iv))) | |
458 | return -EINVAL; | |
459 | break; | |
460 | ||
461 | case ALG_SET_OP: | |
462 | if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32))) | |
463 | return -EINVAL; | |
464 | con->op = *(u32 *)CMSG_DATA(cmsg); | |
465 | break; | |
466 | ||
467 | default: | |
468 | return -EINVAL; | |
469 | } | |
470 | } | |
471 | ||
472 | return 0; | |
473 | } | |
474 | EXPORT_SYMBOL_GPL(af_alg_cmsg_send); | |
475 | ||
476 | int af_alg_wait_for_completion(int err, struct af_alg_completion *completion) | |
477 | { | |
478 | switch (err) { | |
479 | case -EINPROGRESS: | |
480 | case -EBUSY: | |
481 | wait_for_completion(&completion->completion); | |
482 | INIT_COMPLETION(completion->completion); | |
483 | err = completion->err; | |
484 | break; | |
485 | }; | |
486 | ||
487 | return err; | |
488 | } | |
489 | EXPORT_SYMBOL_GPL(af_alg_wait_for_completion); | |
490 | ||
491 | void af_alg_complete(struct crypto_async_request *req, int err) | |
492 | { | |
493 | struct af_alg_completion *completion = req->data; | |
494 | ||
3d53f1f7 RV |
495 | if (err == -EINPROGRESS) |
496 | return; | |
497 | ||
03c8efc1 HX |
498 | completion->err = err; |
499 | complete(&completion->completion); | |
500 | } | |
501 | EXPORT_SYMBOL_GPL(af_alg_complete); | |
502 | ||
503 | static int __init af_alg_init(void) | |
504 | { | |
505 | int err = proto_register(&alg_proto, 0); | |
506 | ||
507 | if (err) | |
508 | goto out; | |
509 | ||
510 | err = sock_register(&alg_family); | |
511 | if (err != 0) | |
512 | goto out_unregister_proto; | |
513 | ||
514 | out: | |
515 | return err; | |
516 | ||
517 | out_unregister_proto: | |
518 | proto_unregister(&alg_proto); | |
519 | goto out; | |
520 | } | |
521 | ||
522 | static void __exit af_alg_exit(void) | |
523 | { | |
524 | sock_unregister(PF_ALG); | |
525 | proto_unregister(&alg_proto); | |
526 | } | |
527 | ||
528 | module_init(af_alg_init); | |
529 | module_exit(af_alg_exit); | |
530 | MODULE_LICENSE("GPL"); | |
531 | MODULE_ALIAS_NETPROTO(AF_ALG); |