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> | |
4c63f83c | 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; | |
79 | node->type = type; | |
80 | list_add(&node->list, &alg_types); | |
81 | err = 0; | |
82 | ||
83 | unlock: | |
84 | up_write(&alg_types_sem); | |
85 | ||
86 | return err; | |
87 | } | |
88 | EXPORT_SYMBOL_GPL(af_alg_register_type); | |
89 | ||
90 | int af_alg_unregister_type(const struct af_alg_type *type) | |
91 | { | |
92 | struct alg_type_list *node; | |
93 | int err = -ENOENT; | |
94 | ||
95 | down_write(&alg_types_sem); | |
96 | list_for_each_entry(node, &alg_types, list) { | |
97 | if (strcmp(node->type->name, type->name)) | |
98 | continue; | |
99 | ||
100 | list_del(&node->list); | |
101 | kfree(node); | |
102 | err = 0; | |
103 | break; | |
104 | } | |
105 | up_write(&alg_types_sem); | |
106 | ||
107 | return err; | |
108 | } | |
109 | EXPORT_SYMBOL_GPL(af_alg_unregister_type); | |
110 | ||
111 | static void alg_do_release(const struct af_alg_type *type, void *private) | |
112 | { | |
113 | if (!type) | |
114 | return; | |
115 | ||
116 | type->release(private); | |
117 | module_put(type->owner); | |
118 | } | |
119 | ||
120 | int af_alg_release(struct socket *sock) | |
121 | { | |
122 | if (sock->sk) | |
123 | sock_put(sock->sk); | |
124 | return 0; | |
125 | } | |
126 | EXPORT_SYMBOL_GPL(af_alg_release); | |
127 | ||
128 | static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) | |
129 | { | |
130 | struct sock *sk = sock->sk; | |
131 | struct alg_sock *ask = alg_sk(sk); | |
132 | struct sockaddr_alg *sa = (void *)uaddr; | |
133 | const struct af_alg_type *type; | |
134 | void *private; | |
135 | ||
136 | if (sock->state == SS_CONNECTED) | |
137 | return -EINVAL; | |
138 | ||
139 | if (addr_len != sizeof(*sa)) | |
140 | return -EINVAL; | |
141 | ||
142 | sa->salg_type[sizeof(sa->salg_type) - 1] = 0; | |
143 | sa->salg_name[sizeof(sa->salg_name) - 1] = 0; | |
144 | ||
145 | type = alg_get_type(sa->salg_type); | |
146 | if (IS_ERR(type) && PTR_ERR(type) == -ENOENT) { | |
147 | request_module("algif-%s", sa->salg_type); | |
148 | type = alg_get_type(sa->salg_type); | |
149 | } | |
150 | ||
151 | if (IS_ERR(type)) | |
152 | return PTR_ERR(type); | |
153 | ||
154 | private = type->bind(sa->salg_name, sa->salg_feat, sa->salg_mask); | |
155 | if (IS_ERR(private)) { | |
156 | module_put(type->owner); | |
157 | return PTR_ERR(private); | |
158 | } | |
159 | ||
160 | lock_sock(sk); | |
161 | ||
162 | swap(ask->type, type); | |
163 | swap(ask->private, private); | |
164 | ||
165 | release_sock(sk); | |
166 | ||
167 | alg_do_release(type, private); | |
168 | ||
169 | return 0; | |
170 | } | |
171 | ||
172 | static int alg_setkey(struct sock *sk, char __user *ukey, | |
173 | unsigned int keylen) | |
174 | { | |
175 | struct alg_sock *ask = alg_sk(sk); | |
176 | const struct af_alg_type *type = ask->type; | |
177 | u8 *key; | |
178 | int err; | |
179 | ||
180 | key = sock_kmalloc(sk, keylen, GFP_KERNEL); | |
181 | if (!key) | |
182 | return -ENOMEM; | |
183 | ||
184 | err = -EFAULT; | |
185 | if (copy_from_user(key, ukey, keylen)) | |
186 | goto out; | |
187 | ||
188 | err = type->setkey(ask->private, key, keylen); | |
189 | ||
190 | out: | |
191 | sock_kfree_s(sk, key, keylen); | |
192 | ||
193 | return err; | |
194 | } | |
195 | ||
196 | static int alg_setsockopt(struct socket *sock, int level, int optname, | |
197 | char __user *optval, unsigned int optlen) | |
198 | { | |
199 | struct sock *sk = sock->sk; | |
200 | struct alg_sock *ask = alg_sk(sk); | |
201 | const struct af_alg_type *type; | |
202 | int err = -ENOPROTOOPT; | |
203 | ||
204 | lock_sock(sk); | |
205 | type = ask->type; | |
206 | ||
207 | if (level != SOL_ALG || !type) | |
208 | goto unlock; | |
209 | ||
210 | switch (optname) { | |
211 | case ALG_SET_KEY: | |
212 | if (sock->state == SS_CONNECTED) | |
213 | goto unlock; | |
214 | if (!type->setkey) | |
215 | goto unlock; | |
216 | ||
217 | err = alg_setkey(sk, optval, optlen); | |
218 | } | |
219 | ||
220 | unlock: | |
221 | release_sock(sk); | |
222 | ||
223 | return err; | |
224 | } | |
225 | ||
226 | int af_alg_accept(struct sock *sk, struct socket *newsock) | |
227 | { | |
228 | struct alg_sock *ask = alg_sk(sk); | |
229 | const struct af_alg_type *type; | |
230 | struct sock *sk2; | |
231 | int err; | |
232 | ||
233 | lock_sock(sk); | |
234 | type = ask->type; | |
235 | ||
236 | err = -EINVAL; | |
237 | if (!type) | |
238 | goto unlock; | |
239 | ||
240 | sk2 = sk_alloc(sock_net(sk), PF_ALG, GFP_KERNEL, &alg_proto); | |
241 | err = -ENOMEM; | |
242 | if (!sk2) | |
243 | goto unlock; | |
244 | ||
245 | sock_init_data(newsock, sk2); | |
507cad35 | 246 | sock_graft(sk2, newsock); |
4c63f83c | 247 | security_sk_clone(sk, sk2); |
03c8efc1 HX |
248 | |
249 | err = type->accept(ask->private, sk2); | |
250 | if (err) { | |
251 | sk_free(sk2); | |
252 | goto unlock; | |
253 | } | |
254 | ||
255 | sk2->sk_family = PF_ALG; | |
256 | ||
257 | sock_hold(sk); | |
258 | alg_sk(sk2)->parent = sk; | |
259 | alg_sk(sk2)->type = type; | |
260 | ||
261 | newsock->ops = type->ops; | |
262 | newsock->state = SS_CONNECTED; | |
263 | ||
264 | err = 0; | |
265 | ||
266 | unlock: | |
267 | release_sock(sk); | |
268 | ||
269 | return err; | |
270 | } | |
271 | EXPORT_SYMBOL_GPL(af_alg_accept); | |
272 | ||
273 | static int alg_accept(struct socket *sock, struct socket *newsock, int flags) | |
274 | { | |
275 | return af_alg_accept(sock->sk, newsock); | |
276 | } | |
277 | ||
278 | static const struct proto_ops alg_proto_ops = { | |
279 | .family = PF_ALG, | |
280 | .owner = THIS_MODULE, | |
281 | ||
282 | .connect = sock_no_connect, | |
283 | .socketpair = sock_no_socketpair, | |
284 | .getname = sock_no_getname, | |
285 | .ioctl = sock_no_ioctl, | |
286 | .listen = sock_no_listen, | |
287 | .shutdown = sock_no_shutdown, | |
288 | .getsockopt = sock_no_getsockopt, | |
289 | .mmap = sock_no_mmap, | |
290 | .sendpage = sock_no_sendpage, | |
291 | .sendmsg = sock_no_sendmsg, | |
292 | .recvmsg = sock_no_recvmsg, | |
293 | .poll = sock_no_poll, | |
294 | ||
295 | .bind = alg_bind, | |
296 | .release = af_alg_release, | |
297 | .setsockopt = alg_setsockopt, | |
298 | .accept = alg_accept, | |
299 | }; | |
300 | ||
301 | static void alg_sock_destruct(struct sock *sk) | |
302 | { | |
303 | struct alg_sock *ask = alg_sk(sk); | |
304 | ||
305 | alg_do_release(ask->type, ask->private); | |
306 | } | |
307 | ||
308 | static int alg_create(struct net *net, struct socket *sock, int protocol, | |
309 | int kern) | |
310 | { | |
311 | struct sock *sk; | |
312 | int err; | |
313 | ||
314 | if (sock->type != SOCK_SEQPACKET) | |
315 | return -ESOCKTNOSUPPORT; | |
316 | if (protocol != 0) | |
317 | return -EPROTONOSUPPORT; | |
318 | ||
319 | err = -ENOMEM; | |
320 | sk = sk_alloc(net, PF_ALG, GFP_KERNEL, &alg_proto); | |
321 | if (!sk) | |
322 | goto out; | |
323 | ||
324 | sock->ops = &alg_proto_ops; | |
325 | sock_init_data(sock, sk); | |
326 | ||
327 | sk->sk_family = PF_ALG; | |
328 | sk->sk_destruct = alg_sock_destruct; | |
329 | ||
330 | return 0; | |
331 | out: | |
332 | return err; | |
333 | } | |
334 | ||
335 | static const struct net_proto_family alg_family = { | |
336 | .family = PF_ALG, | |
337 | .create = alg_create, | |
338 | .owner = THIS_MODULE, | |
339 | }; | |
340 | ||
341 | int af_alg_make_sg(struct af_alg_sgl *sgl, void __user *addr, int len, | |
342 | int write) | |
343 | { | |
344 | unsigned long from = (unsigned long)addr; | |
345 | unsigned long npages; | |
346 | unsigned off; | |
347 | int err; | |
348 | int i; | |
349 | ||
350 | err = -EFAULT; | |
351 | if (!access_ok(write ? VERIFY_READ : VERIFY_WRITE, addr, len)) | |
352 | goto out; | |
353 | ||
354 | off = from & ~PAGE_MASK; | |
355 | npages = (off + len + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
356 | if (npages > ALG_MAX_PAGES) | |
357 | npages = ALG_MAX_PAGES; | |
358 | ||
359 | err = get_user_pages_fast(from, npages, write, sgl->pages); | |
360 | if (err < 0) | |
361 | goto out; | |
362 | ||
363 | npages = err; | |
364 | err = -EINVAL; | |
365 | if (WARN_ON(npages == 0)) | |
366 | goto out; | |
367 | ||
368 | err = 0; | |
369 | ||
370 | sg_init_table(sgl->sg, npages); | |
371 | ||
372 | for (i = 0; i < npages; i++) { | |
373 | int plen = min_t(int, len, PAGE_SIZE - off); | |
374 | ||
375 | sg_set_page(sgl->sg + i, sgl->pages[i], plen, off); | |
376 | ||
377 | off = 0; | |
378 | len -= plen; | |
379 | err += plen; | |
380 | } | |
381 | ||
382 | out: | |
383 | return err; | |
384 | } | |
385 | EXPORT_SYMBOL_GPL(af_alg_make_sg); | |
386 | ||
387 | void af_alg_free_sg(struct af_alg_sgl *sgl) | |
388 | { | |
389 | int i; | |
390 | ||
391 | i = 0; | |
392 | do { | |
393 | put_page(sgl->pages[i]); | |
394 | } while (!sg_is_last(sgl->sg + (i++))); | |
395 | } | |
396 | EXPORT_SYMBOL_GPL(af_alg_free_sg); | |
397 | ||
398 | int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con) | |
399 | { | |
400 | struct cmsghdr *cmsg; | |
401 | ||
f95b414e | 402 | for_each_cmsghdr(cmsg, msg) { |
03c8efc1 HX |
403 | if (!CMSG_OK(msg, cmsg)) |
404 | return -EINVAL; | |
405 | if (cmsg->cmsg_level != SOL_ALG) | |
406 | continue; | |
407 | ||
408 | switch(cmsg->cmsg_type) { | |
409 | case ALG_SET_IV: | |
410 | if (cmsg->cmsg_len < CMSG_LEN(sizeof(*con->iv))) | |
411 | return -EINVAL; | |
412 | con->iv = (void *)CMSG_DATA(cmsg); | |
413 | if (cmsg->cmsg_len < CMSG_LEN(con->iv->ivlen + | |
414 | sizeof(*con->iv))) | |
415 | return -EINVAL; | |
416 | break; | |
417 | ||
418 | case ALG_SET_OP: | |
419 | if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32))) | |
420 | return -EINVAL; | |
421 | con->op = *(u32 *)CMSG_DATA(cmsg); | |
422 | break; | |
423 | ||
af8e8073 SM |
424 | case ALG_SET_AEAD_ASSOCLEN: |
425 | if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32))) | |
426 | return -EINVAL; | |
427 | con->aead_assoclen = *(u32 *)CMSG_DATA(cmsg); | |
428 | break; | |
429 | ||
03c8efc1 HX |
430 | default: |
431 | return -EINVAL; | |
432 | } | |
433 | } | |
434 | ||
435 | return 0; | |
436 | } | |
437 | EXPORT_SYMBOL_GPL(af_alg_cmsg_send); | |
438 | ||
439 | int af_alg_wait_for_completion(int err, struct af_alg_completion *completion) | |
440 | { | |
441 | switch (err) { | |
442 | case -EINPROGRESS: | |
443 | case -EBUSY: | |
444 | wait_for_completion(&completion->completion); | |
16735d02 | 445 | reinit_completion(&completion->completion); |
03c8efc1 HX |
446 | err = completion->err; |
447 | break; | |
448 | }; | |
449 | ||
450 | return err; | |
451 | } | |
452 | EXPORT_SYMBOL_GPL(af_alg_wait_for_completion); | |
453 | ||
454 | void af_alg_complete(struct crypto_async_request *req, int err) | |
455 | { | |
456 | struct af_alg_completion *completion = req->data; | |
457 | ||
458 | completion->err = err; | |
459 | complete(&completion->completion); | |
460 | } | |
461 | EXPORT_SYMBOL_GPL(af_alg_complete); | |
462 | ||
463 | static int __init af_alg_init(void) | |
464 | { | |
465 | int err = proto_register(&alg_proto, 0); | |
466 | ||
467 | if (err) | |
468 | goto out; | |
469 | ||
470 | err = sock_register(&alg_family); | |
471 | if (err != 0) | |
472 | goto out_unregister_proto; | |
473 | ||
474 | out: | |
475 | return err; | |
476 | ||
477 | out_unregister_proto: | |
478 | proto_unregister(&alg_proto); | |
479 | goto out; | |
480 | } | |
481 | ||
482 | static void __exit af_alg_exit(void) | |
483 | { | |
484 | sock_unregister(PF_ALG); | |
485 | proto_unregister(&alg_proto); | |
486 | } | |
487 | ||
488 | module_init(af_alg_init); | |
489 | module_exit(af_alg_exit); | |
490 | MODULE_LICENSE("GPL"); | |
491 | MODULE_ALIAS_NETPROTO(AF_ALG); |