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