Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * NETLINK Kernel-user communication protocol. | |
3 | * | |
113aa838 | 4 | * Authors: Alan Cox <alan@lxorguk.ukuu.org.uk> |
1da177e4 LT |
5 | * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> |
6 | * | |
7 | * This program is free software; you can redistribute it and/or | |
8 | * modify it under the terms of the GNU General Public License | |
9 | * as published by the Free Software Foundation; either version | |
10 | * 2 of the License, or (at your option) any later version. | |
746fac4d | 11 | * |
1da177e4 LT |
12 | * Tue Jun 26 14:36:48 MEST 2001 Herbert "herp" Rosmanith |
13 | * added netlink_proto_exit | |
14 | * Tue Jan 22 18:32:44 BRST 2002 Arnaldo C. de Melo <acme@conectiva.com.br> | |
15 | * use nlk_sk, as sk->protinfo is on a diet 8) | |
4fdb3bb7 HW |
16 | * Fri Jul 22 19:51:12 MEST 2005 Harald Welte <laforge@gnumonks.org> |
17 | * - inc module use count of module that owns | |
18 | * the kernel socket in case userspace opens | |
19 | * socket of same protocol | |
20 | * - remove all module support, since netlink is | |
21 | * mandatory if CONFIG_NET=y these days | |
1da177e4 LT |
22 | */ |
23 | ||
1da177e4 LT |
24 | #include <linux/module.h> |
25 | ||
4fc268d2 | 26 | #include <linux/capability.h> |
1da177e4 LT |
27 | #include <linux/kernel.h> |
28 | #include <linux/init.h> | |
1da177e4 LT |
29 | #include <linux/signal.h> |
30 | #include <linux/sched.h> | |
31 | #include <linux/errno.h> | |
32 | #include <linux/string.h> | |
33 | #include <linux/stat.h> | |
34 | #include <linux/socket.h> | |
35 | #include <linux/un.h> | |
36 | #include <linux/fcntl.h> | |
37 | #include <linux/termios.h> | |
38 | #include <linux/sockios.h> | |
39 | #include <linux/net.h> | |
40 | #include <linux/fs.h> | |
41 | #include <linux/slab.h> | |
42 | #include <asm/uaccess.h> | |
43 | #include <linux/skbuff.h> | |
44 | #include <linux/netdevice.h> | |
45 | #include <linux/rtnetlink.h> | |
46 | #include <linux/proc_fs.h> | |
47 | #include <linux/seq_file.h> | |
1da177e4 LT |
48 | #include <linux/notifier.h> |
49 | #include <linux/security.h> | |
50 | #include <linux/jhash.h> | |
51 | #include <linux/jiffies.h> | |
52 | #include <linux/random.h> | |
53 | #include <linux/bitops.h> | |
54 | #include <linux/mm.h> | |
55 | #include <linux/types.h> | |
54e0f520 | 56 | #include <linux/audit.h> |
af65bdfc | 57 | #include <linux/mutex.h> |
54e0f520 | 58 | |
457c4cbc | 59 | #include <net/net_namespace.h> |
1da177e4 LT |
60 | #include <net/sock.h> |
61 | #include <net/scm.h> | |
82ace47a | 62 | #include <net/netlink.h> |
1da177e4 | 63 | |
0f29c768 | 64 | #include "af_netlink.h" |
1da177e4 | 65 | |
5c398dc8 ED |
66 | struct listeners { |
67 | struct rcu_head rcu; | |
68 | unsigned long masks[0]; | |
6c04bb18 JB |
69 | }; |
70 | ||
cd967e05 PM |
71 | /* state bits */ |
72 | #define NETLINK_CONGESTED 0x0 | |
73 | ||
74 | /* flags */ | |
77247bbb | 75 | #define NETLINK_KERNEL_SOCKET 0x1 |
9a4595bc | 76 | #define NETLINK_RECV_PKTINFO 0x2 |
be0c22a4 | 77 | #define NETLINK_BROADCAST_SEND_ERROR 0x4 |
38938bfe | 78 | #define NETLINK_RECV_NO_ENOBUFS 0x8 |
77247bbb | 79 | |
035c4c16 | 80 | static inline int netlink_is_kernel(struct sock *sk) |
aed81560 DL |
81 | { |
82 | return nlk_sk(sk)->flags & NETLINK_KERNEL_SOCKET; | |
83 | } | |
84 | ||
0f29c768 AV |
85 | struct netlink_table *nl_table; |
86 | EXPORT_SYMBOL_GPL(nl_table); | |
1da177e4 LT |
87 | |
88 | static DECLARE_WAIT_QUEUE_HEAD(nl_table_wait); | |
89 | ||
90 | static int netlink_dump(struct sock *sk); | |
1da177e4 | 91 | |
0f29c768 AV |
92 | DEFINE_RWLOCK(nl_table_lock); |
93 | EXPORT_SYMBOL_GPL(nl_table_lock); | |
1da177e4 LT |
94 | static atomic_t nl_table_users = ATOMIC_INIT(0); |
95 | ||
6d772ac5 ED |
96 | #define nl_deref_protected(X) rcu_dereference_protected(X, lockdep_is_held(&nl_table_lock)); |
97 | ||
e041c683 | 98 | static ATOMIC_NOTIFIER_HEAD(netlink_chain); |
1da177e4 | 99 | |
b57ef81f | 100 | static inline u32 netlink_group_mask(u32 group) |
d629b836 PM |
101 | { |
102 | return group ? 1 << (group - 1) : 0; | |
103 | } | |
104 | ||
15e47304 | 105 | static inline struct hlist_head *nl_portid_hashfn(struct nl_portid_hash *hash, u32 portid) |
1da177e4 | 106 | { |
15e47304 | 107 | return &hash->table[jhash_1word(portid, hash->rnd) & hash->mask]; |
1da177e4 LT |
108 | } |
109 | ||
658cb354 ED |
110 | static void netlink_destroy_callback(struct netlink_callback *cb) |
111 | { | |
112 | kfree_skb(cb->skb); | |
113 | kfree(cb); | |
114 | } | |
115 | ||
bfb253c9 ED |
116 | static void netlink_consume_callback(struct netlink_callback *cb) |
117 | { | |
118 | consume_skb(cb->skb); | |
119 | kfree(cb); | |
120 | } | |
121 | ||
1da177e4 LT |
122 | static void netlink_sock_destruct(struct sock *sk) |
123 | { | |
3f660d66 HX |
124 | struct netlink_sock *nlk = nlk_sk(sk); |
125 | ||
3f660d66 HX |
126 | if (nlk->cb) { |
127 | if (nlk->cb->done) | |
128 | nlk->cb->done(nlk->cb); | |
6dc878a8 G |
129 | |
130 | module_put(nlk->cb->module); | |
3f660d66 HX |
131 | netlink_destroy_callback(nlk->cb); |
132 | } | |
133 | ||
1da177e4 LT |
134 | skb_queue_purge(&sk->sk_receive_queue); |
135 | ||
136 | if (!sock_flag(sk, SOCK_DEAD)) { | |
6ac552fd | 137 | printk(KERN_ERR "Freeing alive netlink socket %p\n", sk); |
1da177e4 LT |
138 | return; |
139 | } | |
547b792c IJ |
140 | |
141 | WARN_ON(atomic_read(&sk->sk_rmem_alloc)); | |
142 | WARN_ON(atomic_read(&sk->sk_wmem_alloc)); | |
143 | WARN_ON(nlk_sk(sk)->groups); | |
1da177e4 LT |
144 | } |
145 | ||
6ac552fd PM |
146 | /* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on |
147 | * SMP. Look, when several writers sleep and reader wakes them up, all but one | |
1da177e4 LT |
148 | * immediately hit write lock and grab all the cpus. Exclusive sleep solves |
149 | * this, _but_ remember, it adds useless work on UP machines. | |
150 | */ | |
151 | ||
d136f1bd | 152 | void netlink_table_grab(void) |
9a429c49 | 153 | __acquires(nl_table_lock) |
1da177e4 | 154 | { |
d136f1bd JB |
155 | might_sleep(); |
156 | ||
6abd219c | 157 | write_lock_irq(&nl_table_lock); |
1da177e4 LT |
158 | |
159 | if (atomic_read(&nl_table_users)) { | |
160 | DECLARE_WAITQUEUE(wait, current); | |
161 | ||
162 | add_wait_queue_exclusive(&nl_table_wait, &wait); | |
6ac552fd | 163 | for (;;) { |
1da177e4 LT |
164 | set_current_state(TASK_UNINTERRUPTIBLE); |
165 | if (atomic_read(&nl_table_users) == 0) | |
166 | break; | |
6abd219c | 167 | write_unlock_irq(&nl_table_lock); |
1da177e4 | 168 | schedule(); |
6abd219c | 169 | write_lock_irq(&nl_table_lock); |
1da177e4 LT |
170 | } |
171 | ||
172 | __set_current_state(TASK_RUNNING); | |
173 | remove_wait_queue(&nl_table_wait, &wait); | |
174 | } | |
175 | } | |
176 | ||
d136f1bd | 177 | void netlink_table_ungrab(void) |
9a429c49 | 178 | __releases(nl_table_lock) |
1da177e4 | 179 | { |
6abd219c | 180 | write_unlock_irq(&nl_table_lock); |
1da177e4 LT |
181 | wake_up(&nl_table_wait); |
182 | } | |
183 | ||
6ac552fd | 184 | static inline void |
1da177e4 LT |
185 | netlink_lock_table(void) |
186 | { | |
187 | /* read_lock() synchronizes us to netlink_table_grab */ | |
188 | ||
189 | read_lock(&nl_table_lock); | |
190 | atomic_inc(&nl_table_users); | |
191 | read_unlock(&nl_table_lock); | |
192 | } | |
193 | ||
6ac552fd | 194 | static inline void |
1da177e4 LT |
195 | netlink_unlock_table(void) |
196 | { | |
197 | if (atomic_dec_and_test(&nl_table_users)) | |
198 | wake_up(&nl_table_wait); | |
199 | } | |
200 | ||
15e47304 | 201 | static struct sock *netlink_lookup(struct net *net, int protocol, u32 portid) |
1da177e4 | 202 | { |
15e47304 | 203 | struct nl_portid_hash *hash = &nl_table[protocol].hash; |
1da177e4 LT |
204 | struct hlist_head *head; |
205 | struct sock *sk; | |
1da177e4 LT |
206 | |
207 | read_lock(&nl_table_lock); | |
15e47304 | 208 | head = nl_portid_hashfn(hash, portid); |
b67bfe0d | 209 | sk_for_each(sk, head) { |
15e47304 | 210 | if (net_eq(sock_net(sk), net) && (nlk_sk(sk)->portid == portid)) { |
1da177e4 LT |
211 | sock_hold(sk); |
212 | goto found; | |
213 | } | |
214 | } | |
215 | sk = NULL; | |
216 | found: | |
217 | read_unlock(&nl_table_lock); | |
218 | return sk; | |
219 | } | |
220 | ||
15e47304 | 221 | static struct hlist_head *nl_portid_hash_zalloc(size_t size) |
1da177e4 LT |
222 | { |
223 | if (size <= PAGE_SIZE) | |
ea72912c | 224 | return kzalloc(size, GFP_ATOMIC); |
1da177e4 LT |
225 | else |
226 | return (struct hlist_head *) | |
ea72912c ED |
227 | __get_free_pages(GFP_ATOMIC | __GFP_ZERO, |
228 | get_order(size)); | |
1da177e4 LT |
229 | } |
230 | ||
15e47304 | 231 | static void nl_portid_hash_free(struct hlist_head *table, size_t size) |
1da177e4 LT |
232 | { |
233 | if (size <= PAGE_SIZE) | |
234 | kfree(table); | |
235 | else | |
236 | free_pages((unsigned long)table, get_order(size)); | |
237 | } | |
238 | ||
15e47304 | 239 | static int nl_portid_hash_rehash(struct nl_portid_hash *hash, int grow) |
1da177e4 LT |
240 | { |
241 | unsigned int omask, mask, shift; | |
242 | size_t osize, size; | |
243 | struct hlist_head *otable, *table; | |
244 | int i; | |
245 | ||
246 | omask = mask = hash->mask; | |
247 | osize = size = (mask + 1) * sizeof(*table); | |
248 | shift = hash->shift; | |
249 | ||
250 | if (grow) { | |
251 | if (++shift > hash->max_shift) | |
252 | return 0; | |
253 | mask = mask * 2 + 1; | |
254 | size *= 2; | |
255 | } | |
256 | ||
15e47304 | 257 | table = nl_portid_hash_zalloc(size); |
1da177e4 LT |
258 | if (!table) |
259 | return 0; | |
260 | ||
1da177e4 LT |
261 | otable = hash->table; |
262 | hash->table = table; | |
263 | hash->mask = mask; | |
264 | hash->shift = shift; | |
265 | get_random_bytes(&hash->rnd, sizeof(hash->rnd)); | |
266 | ||
267 | for (i = 0; i <= omask; i++) { | |
268 | struct sock *sk; | |
b67bfe0d | 269 | struct hlist_node *tmp; |
1da177e4 | 270 | |
b67bfe0d | 271 | sk_for_each_safe(sk, tmp, &otable[i]) |
15e47304 | 272 | __sk_add_node(sk, nl_portid_hashfn(hash, nlk_sk(sk)->portid)); |
1da177e4 LT |
273 | } |
274 | ||
15e47304 | 275 | nl_portid_hash_free(otable, osize); |
1da177e4 LT |
276 | hash->rehash_time = jiffies + 10 * 60 * HZ; |
277 | return 1; | |
278 | } | |
279 | ||
15e47304 | 280 | static inline int nl_portid_hash_dilute(struct nl_portid_hash *hash, int len) |
1da177e4 LT |
281 | { |
282 | int avg = hash->entries >> hash->shift; | |
283 | ||
15e47304 | 284 | if (unlikely(avg > 1) && nl_portid_hash_rehash(hash, 1)) |
1da177e4 LT |
285 | return 1; |
286 | ||
287 | if (unlikely(len > avg) && time_after(jiffies, hash->rehash_time)) { | |
15e47304 | 288 | nl_portid_hash_rehash(hash, 0); |
1da177e4 LT |
289 | return 1; |
290 | } | |
291 | ||
292 | return 0; | |
293 | } | |
294 | ||
90ddc4f0 | 295 | static const struct proto_ops netlink_ops; |
1da177e4 | 296 | |
4277a083 PM |
297 | static void |
298 | netlink_update_listeners(struct sock *sk) | |
299 | { | |
300 | struct netlink_table *tbl = &nl_table[sk->sk_protocol]; | |
4277a083 PM |
301 | unsigned long mask; |
302 | unsigned int i; | |
6d772ac5 ED |
303 | struct listeners *listeners; |
304 | ||
305 | listeners = nl_deref_protected(tbl->listeners); | |
306 | if (!listeners) | |
307 | return; | |
4277a083 | 308 | |
b4ff4f04 | 309 | for (i = 0; i < NLGRPLONGS(tbl->groups); i++) { |
4277a083 | 310 | mask = 0; |
b67bfe0d | 311 | sk_for_each_bound(sk, &tbl->mc_list) { |
b4ff4f04 JB |
312 | if (i < NLGRPLONGS(nlk_sk(sk)->ngroups)) |
313 | mask |= nlk_sk(sk)->groups[i]; | |
314 | } | |
6d772ac5 | 315 | listeners->masks[i] = mask; |
4277a083 PM |
316 | } |
317 | /* this function is only called with the netlink table "grabbed", which | |
318 | * makes sure updates are visible before bind or setsockopt return. */ | |
319 | } | |
320 | ||
15e47304 | 321 | static int netlink_insert(struct sock *sk, struct net *net, u32 portid) |
1da177e4 | 322 | { |
15e47304 | 323 | struct nl_portid_hash *hash = &nl_table[sk->sk_protocol].hash; |
1da177e4 LT |
324 | struct hlist_head *head; |
325 | int err = -EADDRINUSE; | |
326 | struct sock *osk; | |
1da177e4 LT |
327 | int len; |
328 | ||
329 | netlink_table_grab(); | |
15e47304 | 330 | head = nl_portid_hashfn(hash, portid); |
1da177e4 | 331 | len = 0; |
b67bfe0d | 332 | sk_for_each(osk, head) { |
15e47304 | 333 | if (net_eq(sock_net(osk), net) && (nlk_sk(osk)->portid == portid)) |
1da177e4 LT |
334 | break; |
335 | len++; | |
336 | } | |
b67bfe0d | 337 | if (osk) |
1da177e4 LT |
338 | goto err; |
339 | ||
340 | err = -EBUSY; | |
15e47304 | 341 | if (nlk_sk(sk)->portid) |
1da177e4 LT |
342 | goto err; |
343 | ||
344 | err = -ENOMEM; | |
345 | if (BITS_PER_LONG > 32 && unlikely(hash->entries >= UINT_MAX)) | |
346 | goto err; | |
347 | ||
15e47304 EB |
348 | if (len && nl_portid_hash_dilute(hash, len)) |
349 | head = nl_portid_hashfn(hash, portid); | |
1da177e4 | 350 | hash->entries++; |
15e47304 | 351 | nlk_sk(sk)->portid = portid; |
1da177e4 LT |
352 | sk_add_node(sk, head); |
353 | err = 0; | |
354 | ||
355 | err: | |
356 | netlink_table_ungrab(); | |
357 | return err; | |
358 | } | |
359 | ||
360 | static void netlink_remove(struct sock *sk) | |
361 | { | |
362 | netlink_table_grab(); | |
d470e3b4 DM |
363 | if (sk_del_node_init(sk)) |
364 | nl_table[sk->sk_protocol].hash.entries--; | |
f7fa9b10 | 365 | if (nlk_sk(sk)->subscriptions) |
1da177e4 LT |
366 | __sk_del_bind_node(sk); |
367 | netlink_table_ungrab(); | |
368 | } | |
369 | ||
370 | static struct proto netlink_proto = { | |
371 | .name = "NETLINK", | |
372 | .owner = THIS_MODULE, | |
373 | .obj_size = sizeof(struct netlink_sock), | |
374 | }; | |
375 | ||
1b8d7ae4 EB |
376 | static int __netlink_create(struct net *net, struct socket *sock, |
377 | struct mutex *cb_mutex, int protocol) | |
1da177e4 LT |
378 | { |
379 | struct sock *sk; | |
380 | struct netlink_sock *nlk; | |
ab33a171 PM |
381 | |
382 | sock->ops = &netlink_ops; | |
383 | ||
6257ff21 | 384 | sk = sk_alloc(net, PF_NETLINK, GFP_KERNEL, &netlink_proto); |
ab33a171 PM |
385 | if (!sk) |
386 | return -ENOMEM; | |
387 | ||
388 | sock_init_data(sock, sk); | |
389 | ||
390 | nlk = nlk_sk(sk); | |
658cb354 | 391 | if (cb_mutex) { |
ffa4d721 | 392 | nlk->cb_mutex = cb_mutex; |
658cb354 | 393 | } else { |
ffa4d721 PM |
394 | nlk->cb_mutex = &nlk->cb_def_mutex; |
395 | mutex_init(nlk->cb_mutex); | |
396 | } | |
ab33a171 PM |
397 | init_waitqueue_head(&nlk->wait); |
398 | ||
399 | sk->sk_destruct = netlink_sock_destruct; | |
400 | sk->sk_protocol = protocol; | |
401 | return 0; | |
402 | } | |
403 | ||
3f378b68 EP |
404 | static int netlink_create(struct net *net, struct socket *sock, int protocol, |
405 | int kern) | |
ab33a171 PM |
406 | { |
407 | struct module *module = NULL; | |
af65bdfc | 408 | struct mutex *cb_mutex; |
f7fa9b10 | 409 | struct netlink_sock *nlk; |
03292745 | 410 | void (*bind)(int group); |
ab33a171 | 411 | int err = 0; |
1da177e4 LT |
412 | |
413 | sock->state = SS_UNCONNECTED; | |
414 | ||
415 | if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM) | |
416 | return -ESOCKTNOSUPPORT; | |
417 | ||
6ac552fd | 418 | if (protocol < 0 || protocol >= MAX_LINKS) |
1da177e4 LT |
419 | return -EPROTONOSUPPORT; |
420 | ||
77247bbb | 421 | netlink_lock_table(); |
95a5afca | 422 | #ifdef CONFIG_MODULES |
ab33a171 | 423 | if (!nl_table[protocol].registered) { |
77247bbb | 424 | netlink_unlock_table(); |
4fdb3bb7 | 425 | request_module("net-pf-%d-proto-%d", PF_NETLINK, protocol); |
77247bbb | 426 | netlink_lock_table(); |
4fdb3bb7 | 427 | } |
ab33a171 PM |
428 | #endif |
429 | if (nl_table[protocol].registered && | |
430 | try_module_get(nl_table[protocol].module)) | |
431 | module = nl_table[protocol].module; | |
974c37e9 AD |
432 | else |
433 | err = -EPROTONOSUPPORT; | |
af65bdfc | 434 | cb_mutex = nl_table[protocol].cb_mutex; |
03292745 | 435 | bind = nl_table[protocol].bind; |
77247bbb | 436 | netlink_unlock_table(); |
4fdb3bb7 | 437 | |
974c37e9 AD |
438 | if (err < 0) |
439 | goto out; | |
440 | ||
6ac552fd PM |
441 | err = __netlink_create(net, sock, cb_mutex, protocol); |
442 | if (err < 0) | |
f7fa9b10 PM |
443 | goto out_module; |
444 | ||
6f756a8c | 445 | local_bh_disable(); |
c1fd3b94 | 446 | sock_prot_inuse_add(net, &netlink_proto, 1); |
6f756a8c DM |
447 | local_bh_enable(); |
448 | ||
f7fa9b10 | 449 | nlk = nlk_sk(sock->sk); |
f7fa9b10 | 450 | nlk->module = module; |
03292745 | 451 | nlk->netlink_bind = bind; |
ab33a171 PM |
452 | out: |
453 | return err; | |
1da177e4 | 454 | |
ab33a171 PM |
455 | out_module: |
456 | module_put(module); | |
457 | goto out; | |
1da177e4 LT |
458 | } |
459 | ||
460 | static int netlink_release(struct socket *sock) | |
461 | { | |
462 | struct sock *sk = sock->sk; | |
463 | struct netlink_sock *nlk; | |
464 | ||
465 | if (!sk) | |
466 | return 0; | |
467 | ||
468 | netlink_remove(sk); | |
ac57b3a9 | 469 | sock_orphan(sk); |
1da177e4 LT |
470 | nlk = nlk_sk(sk); |
471 | ||
3f660d66 HX |
472 | /* |
473 | * OK. Socket is unlinked, any packets that arrive now | |
474 | * will be purged. | |
475 | */ | |
1da177e4 | 476 | |
1da177e4 LT |
477 | sock->sk = NULL; |
478 | wake_up_interruptible_all(&nlk->wait); | |
479 | ||
480 | skb_queue_purge(&sk->sk_write_queue); | |
481 | ||
15e47304 | 482 | if (nlk->portid) { |
1da177e4 | 483 | struct netlink_notify n = { |
3b1e0a65 | 484 | .net = sock_net(sk), |
1da177e4 | 485 | .protocol = sk->sk_protocol, |
15e47304 | 486 | .portid = nlk->portid, |
1da177e4 | 487 | }; |
e041c683 AS |
488 | atomic_notifier_call_chain(&netlink_chain, |
489 | NETLINK_URELEASE, &n); | |
746fac4d | 490 | } |
4fdb3bb7 | 491 | |
5e7c001c | 492 | module_put(nlk->module); |
4fdb3bb7 | 493 | |
4277a083 | 494 | netlink_table_grab(); |
aed81560 | 495 | if (netlink_is_kernel(sk)) { |
869e58f8 DL |
496 | BUG_ON(nl_table[sk->sk_protocol].registered == 0); |
497 | if (--nl_table[sk->sk_protocol].registered == 0) { | |
6d772ac5 ED |
498 | struct listeners *old; |
499 | ||
500 | old = nl_deref_protected(nl_table[sk->sk_protocol].listeners); | |
501 | RCU_INIT_POINTER(nl_table[sk->sk_protocol].listeners, NULL); | |
502 | kfree_rcu(old, rcu); | |
869e58f8 | 503 | nl_table[sk->sk_protocol].module = NULL; |
9785e10a PNA |
504 | nl_table[sk->sk_protocol].bind = NULL; |
505 | nl_table[sk->sk_protocol].flags = 0; | |
869e58f8 DL |
506 | nl_table[sk->sk_protocol].registered = 0; |
507 | } | |
658cb354 | 508 | } else if (nlk->subscriptions) { |
4277a083 | 509 | netlink_update_listeners(sk); |
658cb354 | 510 | } |
4277a083 | 511 | netlink_table_ungrab(); |
77247bbb | 512 | |
f7fa9b10 PM |
513 | kfree(nlk->groups); |
514 | nlk->groups = NULL; | |
515 | ||
3755810c | 516 | local_bh_disable(); |
c1fd3b94 | 517 | sock_prot_inuse_add(sock_net(sk), &netlink_proto, -1); |
3755810c | 518 | local_bh_enable(); |
1da177e4 LT |
519 | sock_put(sk); |
520 | return 0; | |
521 | } | |
522 | ||
523 | static int netlink_autobind(struct socket *sock) | |
524 | { | |
525 | struct sock *sk = sock->sk; | |
3b1e0a65 | 526 | struct net *net = sock_net(sk); |
15e47304 | 527 | struct nl_portid_hash *hash = &nl_table[sk->sk_protocol].hash; |
1da177e4 LT |
528 | struct hlist_head *head; |
529 | struct sock *osk; | |
15e47304 | 530 | s32 portid = task_tgid_vnr(current); |
1da177e4 LT |
531 | int err; |
532 | static s32 rover = -4097; | |
533 | ||
534 | retry: | |
535 | cond_resched(); | |
536 | netlink_table_grab(); | |
15e47304 | 537 | head = nl_portid_hashfn(hash, portid); |
b67bfe0d | 538 | sk_for_each(osk, head) { |
878628fb | 539 | if (!net_eq(sock_net(osk), net)) |
b4b51029 | 540 | continue; |
15e47304 EB |
541 | if (nlk_sk(osk)->portid == portid) { |
542 | /* Bind collision, search negative portid values. */ | |
543 | portid = rover--; | |
1da177e4 LT |
544 | if (rover > -4097) |
545 | rover = -4097; | |
546 | netlink_table_ungrab(); | |
547 | goto retry; | |
548 | } | |
549 | } | |
550 | netlink_table_ungrab(); | |
551 | ||
15e47304 | 552 | err = netlink_insert(sk, net, portid); |
1da177e4 LT |
553 | if (err == -EADDRINUSE) |
554 | goto retry; | |
d470e3b4 DM |
555 | |
556 | /* If 2 threads race to autobind, that is fine. */ | |
557 | if (err == -EBUSY) | |
558 | err = 0; | |
559 | ||
560 | return err; | |
1da177e4 LT |
561 | } |
562 | ||
b57ef81f | 563 | static inline int netlink_capable(const struct socket *sock, unsigned int flag) |
746fac4d | 564 | { |
9785e10a | 565 | return (nl_table[sock->sk->sk_protocol].flags & flag) || |
df008c91 | 566 | ns_capable(sock_net(sock->sk)->user_ns, CAP_NET_ADMIN); |
746fac4d | 567 | } |
1da177e4 | 568 | |
f7fa9b10 PM |
569 | static void |
570 | netlink_update_subscriptions(struct sock *sk, unsigned int subscriptions) | |
571 | { | |
572 | struct netlink_sock *nlk = nlk_sk(sk); | |
573 | ||
574 | if (nlk->subscriptions && !subscriptions) | |
575 | __sk_del_bind_node(sk); | |
576 | else if (!nlk->subscriptions && subscriptions) | |
577 | sk_add_bind_node(sk, &nl_table[sk->sk_protocol].mc_list); | |
578 | nlk->subscriptions = subscriptions; | |
579 | } | |
580 | ||
b4ff4f04 | 581 | static int netlink_realloc_groups(struct sock *sk) |
513c2500 PM |
582 | { |
583 | struct netlink_sock *nlk = nlk_sk(sk); | |
584 | unsigned int groups; | |
b4ff4f04 | 585 | unsigned long *new_groups; |
513c2500 PM |
586 | int err = 0; |
587 | ||
b4ff4f04 JB |
588 | netlink_table_grab(); |
589 | ||
513c2500 | 590 | groups = nl_table[sk->sk_protocol].groups; |
b4ff4f04 | 591 | if (!nl_table[sk->sk_protocol].registered) { |
513c2500 | 592 | err = -ENOENT; |
b4ff4f04 JB |
593 | goto out_unlock; |
594 | } | |
513c2500 | 595 | |
b4ff4f04 JB |
596 | if (nlk->ngroups >= groups) |
597 | goto out_unlock; | |
513c2500 | 598 | |
b4ff4f04 JB |
599 | new_groups = krealloc(nlk->groups, NLGRPSZ(groups), GFP_ATOMIC); |
600 | if (new_groups == NULL) { | |
601 | err = -ENOMEM; | |
602 | goto out_unlock; | |
603 | } | |
6ac552fd | 604 | memset((char *)new_groups + NLGRPSZ(nlk->ngroups), 0, |
b4ff4f04 JB |
605 | NLGRPSZ(groups) - NLGRPSZ(nlk->ngroups)); |
606 | ||
607 | nlk->groups = new_groups; | |
513c2500 | 608 | nlk->ngroups = groups; |
b4ff4f04 JB |
609 | out_unlock: |
610 | netlink_table_ungrab(); | |
611 | return err; | |
513c2500 PM |
612 | } |
613 | ||
6ac552fd PM |
614 | static int netlink_bind(struct socket *sock, struct sockaddr *addr, |
615 | int addr_len) | |
1da177e4 LT |
616 | { |
617 | struct sock *sk = sock->sk; | |
3b1e0a65 | 618 | struct net *net = sock_net(sk); |
1da177e4 LT |
619 | struct netlink_sock *nlk = nlk_sk(sk); |
620 | struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr; | |
621 | int err; | |
746fac4d | 622 | |
4e4b5376 HFS |
623 | if (addr_len < sizeof(struct sockaddr_nl)) |
624 | return -EINVAL; | |
625 | ||
1da177e4 LT |
626 | if (nladdr->nl_family != AF_NETLINK) |
627 | return -EINVAL; | |
628 | ||
629 | /* Only superuser is allowed to listen multicasts */ | |
513c2500 | 630 | if (nladdr->nl_groups) { |
9785e10a | 631 | if (!netlink_capable(sock, NL_CFG_F_NONROOT_RECV)) |
513c2500 | 632 | return -EPERM; |
b4ff4f04 JB |
633 | err = netlink_realloc_groups(sk); |
634 | if (err) | |
635 | return err; | |
513c2500 | 636 | } |
1da177e4 | 637 | |
15e47304 EB |
638 | if (nlk->portid) { |
639 | if (nladdr->nl_pid != nlk->portid) | |
1da177e4 LT |
640 | return -EINVAL; |
641 | } else { | |
642 | err = nladdr->nl_pid ? | |
b4b51029 | 643 | netlink_insert(sk, net, nladdr->nl_pid) : |
1da177e4 LT |
644 | netlink_autobind(sock); |
645 | if (err) | |
646 | return err; | |
647 | } | |
648 | ||
513c2500 | 649 | if (!nladdr->nl_groups && (nlk->groups == NULL || !(u32)nlk->groups[0])) |
1da177e4 LT |
650 | return 0; |
651 | ||
652 | netlink_table_grab(); | |
f7fa9b10 | 653 | netlink_update_subscriptions(sk, nlk->subscriptions + |
746fac4d YH |
654 | hweight32(nladdr->nl_groups) - |
655 | hweight32(nlk->groups[0])); | |
656 | nlk->groups[0] = (nlk->groups[0] & ~0xffffffffUL) | nladdr->nl_groups; | |
4277a083 | 657 | netlink_update_listeners(sk); |
1da177e4 LT |
658 | netlink_table_ungrab(); |
659 | ||
03292745 PNA |
660 | if (nlk->netlink_bind && nlk->groups[0]) { |
661 | int i; | |
662 | ||
663 | for (i=0; i<nlk->ngroups; i++) { | |
664 | if (test_bit(i, nlk->groups)) | |
665 | nlk->netlink_bind(i); | |
666 | } | |
667 | } | |
668 | ||
1da177e4 LT |
669 | return 0; |
670 | } | |
671 | ||
672 | static int netlink_connect(struct socket *sock, struct sockaddr *addr, | |
673 | int alen, int flags) | |
674 | { | |
675 | int err = 0; | |
676 | struct sock *sk = sock->sk; | |
677 | struct netlink_sock *nlk = nlk_sk(sk); | |
6ac552fd | 678 | struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr; |
1da177e4 | 679 | |
6503d961 CG |
680 | if (alen < sizeof(addr->sa_family)) |
681 | return -EINVAL; | |
682 | ||
1da177e4 LT |
683 | if (addr->sa_family == AF_UNSPEC) { |
684 | sk->sk_state = NETLINK_UNCONNECTED; | |
15e47304 | 685 | nlk->dst_portid = 0; |
d629b836 | 686 | nlk->dst_group = 0; |
1da177e4 LT |
687 | return 0; |
688 | } | |
689 | if (addr->sa_family != AF_NETLINK) | |
690 | return -EINVAL; | |
691 | ||
692 | /* Only superuser is allowed to send multicasts */ | |
9785e10a | 693 | if (nladdr->nl_groups && !netlink_capable(sock, NL_CFG_F_NONROOT_SEND)) |
1da177e4 LT |
694 | return -EPERM; |
695 | ||
15e47304 | 696 | if (!nlk->portid) |
1da177e4 LT |
697 | err = netlink_autobind(sock); |
698 | ||
699 | if (err == 0) { | |
700 | sk->sk_state = NETLINK_CONNECTED; | |
15e47304 | 701 | nlk->dst_portid = nladdr->nl_pid; |
d629b836 | 702 | nlk->dst_group = ffs(nladdr->nl_groups); |
1da177e4 LT |
703 | } |
704 | ||
705 | return err; | |
706 | } | |
707 | ||
6ac552fd PM |
708 | static int netlink_getname(struct socket *sock, struct sockaddr *addr, |
709 | int *addr_len, int peer) | |
1da177e4 LT |
710 | { |
711 | struct sock *sk = sock->sk; | |
712 | struct netlink_sock *nlk = nlk_sk(sk); | |
13cfa97b | 713 | DECLARE_SOCKADDR(struct sockaddr_nl *, nladdr, addr); |
746fac4d | 714 | |
1da177e4 LT |
715 | nladdr->nl_family = AF_NETLINK; |
716 | nladdr->nl_pad = 0; | |
717 | *addr_len = sizeof(*nladdr); | |
718 | ||
719 | if (peer) { | |
15e47304 | 720 | nladdr->nl_pid = nlk->dst_portid; |
d629b836 | 721 | nladdr->nl_groups = netlink_group_mask(nlk->dst_group); |
1da177e4 | 722 | } else { |
15e47304 | 723 | nladdr->nl_pid = nlk->portid; |
513c2500 | 724 | nladdr->nl_groups = nlk->groups ? nlk->groups[0] : 0; |
1da177e4 LT |
725 | } |
726 | return 0; | |
727 | } | |
728 | ||
729 | static void netlink_overrun(struct sock *sk) | |
730 | { | |
38938bfe PNA |
731 | struct netlink_sock *nlk = nlk_sk(sk); |
732 | ||
733 | if (!(nlk->flags & NETLINK_RECV_NO_ENOBUFS)) { | |
cd967e05 | 734 | if (!test_and_set_bit(NETLINK_CONGESTED, &nlk_sk(sk)->state)) { |
38938bfe PNA |
735 | sk->sk_err = ENOBUFS; |
736 | sk->sk_error_report(sk); | |
737 | } | |
1da177e4 | 738 | } |
38938bfe | 739 | atomic_inc(&sk->sk_drops); |
1da177e4 LT |
740 | } |
741 | ||
15e47304 | 742 | static struct sock *netlink_getsockbyportid(struct sock *ssk, u32 portid) |
1da177e4 | 743 | { |
1da177e4 LT |
744 | struct sock *sock; |
745 | struct netlink_sock *nlk; | |
746 | ||
15e47304 | 747 | sock = netlink_lookup(sock_net(ssk), ssk->sk_protocol, portid); |
1da177e4 LT |
748 | if (!sock) |
749 | return ERR_PTR(-ECONNREFUSED); | |
750 | ||
751 | /* Don't bother queuing skb if kernel socket has no input function */ | |
752 | nlk = nlk_sk(sock); | |
cd40b7d3 | 753 | if (sock->sk_state == NETLINK_CONNECTED && |
15e47304 | 754 | nlk->dst_portid != nlk_sk(ssk)->portid) { |
1da177e4 LT |
755 | sock_put(sock); |
756 | return ERR_PTR(-ECONNREFUSED); | |
757 | } | |
758 | return sock; | |
759 | } | |
760 | ||
761 | struct sock *netlink_getsockbyfilp(struct file *filp) | |
762 | { | |
496ad9aa | 763 | struct inode *inode = file_inode(filp); |
1da177e4 LT |
764 | struct sock *sock; |
765 | ||
766 | if (!S_ISSOCK(inode->i_mode)) | |
767 | return ERR_PTR(-ENOTSOCK); | |
768 | ||
769 | sock = SOCKET_I(inode)->sk; | |
770 | if (sock->sk_family != AF_NETLINK) | |
771 | return ERR_PTR(-EINVAL); | |
772 | ||
773 | sock_hold(sock); | |
774 | return sock; | |
775 | } | |
776 | ||
777 | /* | |
778 | * Attach a skb to a netlink socket. | |
779 | * The caller must hold a reference to the destination socket. On error, the | |
780 | * reference is dropped. The skb is not send to the destination, just all | |
781 | * all error checks are performed and memory in the queue is reserved. | |
782 | * Return values: | |
783 | * < 0: error. skb freed, reference to sock dropped. | |
784 | * 0: continue | |
785 | * 1: repeat lookup - reference dropped while waiting for socket memory. | |
786 | */ | |
9457afee | 787 | int netlink_attachskb(struct sock *sk, struct sk_buff *skb, |
c3d8d1e3 | 788 | long *timeo, struct sock *ssk) |
1da177e4 LT |
789 | { |
790 | struct netlink_sock *nlk; | |
791 | ||
792 | nlk = nlk_sk(sk); | |
793 | ||
794 | if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || | |
cd967e05 | 795 | test_bit(NETLINK_CONGESTED, &nlk->state)) { |
1da177e4 | 796 | DECLARE_WAITQUEUE(wait, current); |
c3d8d1e3 | 797 | if (!*timeo) { |
aed81560 | 798 | if (!ssk || netlink_is_kernel(ssk)) |
1da177e4 LT |
799 | netlink_overrun(sk); |
800 | sock_put(sk); | |
801 | kfree_skb(skb); | |
802 | return -EAGAIN; | |
803 | } | |
804 | ||
805 | __set_current_state(TASK_INTERRUPTIBLE); | |
806 | add_wait_queue(&nlk->wait, &wait); | |
807 | ||
808 | if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || | |
cd967e05 | 809 | test_bit(NETLINK_CONGESTED, &nlk->state)) && |
1da177e4 | 810 | !sock_flag(sk, SOCK_DEAD)) |
c3d8d1e3 | 811 | *timeo = schedule_timeout(*timeo); |
1da177e4 LT |
812 | |
813 | __set_current_state(TASK_RUNNING); | |
814 | remove_wait_queue(&nlk->wait, &wait); | |
815 | sock_put(sk); | |
816 | ||
817 | if (signal_pending(current)) { | |
818 | kfree_skb(skb); | |
c3d8d1e3 | 819 | return sock_intr_errno(*timeo); |
1da177e4 LT |
820 | } |
821 | return 1; | |
822 | } | |
823 | skb_set_owner_r(skb, sk); | |
824 | return 0; | |
825 | } | |
826 | ||
4a7e7c2a | 827 | static int __netlink_sendskb(struct sock *sk, struct sk_buff *skb) |
1da177e4 | 828 | { |
1da177e4 LT |
829 | int len = skb->len; |
830 | ||
1da177e4 LT |
831 | skb_queue_tail(&sk->sk_receive_queue, skb); |
832 | sk->sk_data_ready(sk, len); | |
4a7e7c2a ED |
833 | return len; |
834 | } | |
835 | ||
836 | int netlink_sendskb(struct sock *sk, struct sk_buff *skb) | |
837 | { | |
838 | int len = __netlink_sendskb(sk, skb); | |
839 | ||
1da177e4 LT |
840 | sock_put(sk); |
841 | return len; | |
842 | } | |
843 | ||
844 | void netlink_detachskb(struct sock *sk, struct sk_buff *skb) | |
845 | { | |
846 | kfree_skb(skb); | |
847 | sock_put(sk); | |
848 | } | |
849 | ||
b57ef81f | 850 | static struct sk_buff *netlink_trim(struct sk_buff *skb, gfp_t allocation) |
1da177e4 LT |
851 | { |
852 | int delta; | |
853 | ||
854 | skb_orphan(skb); | |
855 | ||
4305b541 | 856 | delta = skb->end - skb->tail; |
1da177e4 LT |
857 | if (delta * 2 < skb->truesize) |
858 | return skb; | |
859 | ||
860 | if (skb_shared(skb)) { | |
861 | struct sk_buff *nskb = skb_clone(skb, allocation); | |
862 | if (!nskb) | |
863 | return skb; | |
8460c00f | 864 | consume_skb(skb); |
1da177e4 LT |
865 | skb = nskb; |
866 | } | |
867 | ||
868 | if (!pskb_expand_head(skb, 0, -delta, allocation)) | |
869 | skb->truesize -= delta; | |
870 | ||
871 | return skb; | |
872 | } | |
873 | ||
b57ef81f | 874 | static void netlink_rcv_wake(struct sock *sk) |
cd40b7d3 DL |
875 | { |
876 | struct netlink_sock *nlk = nlk_sk(sk); | |
877 | ||
878 | if (skb_queue_empty(&sk->sk_receive_queue)) | |
cd967e05 PM |
879 | clear_bit(NETLINK_CONGESTED, &nlk->state); |
880 | if (!test_bit(NETLINK_CONGESTED, &nlk->state)) | |
cd40b7d3 DL |
881 | wake_up_interruptible(&nlk->wait); |
882 | } | |
883 | ||
3fbc2905 EB |
884 | static int netlink_unicast_kernel(struct sock *sk, struct sk_buff *skb, |
885 | struct sock *ssk) | |
cd40b7d3 DL |
886 | { |
887 | int ret; | |
888 | struct netlink_sock *nlk = nlk_sk(sk); | |
889 | ||
890 | ret = -ECONNREFUSED; | |
891 | if (nlk->netlink_rcv != NULL) { | |
892 | ret = skb->len; | |
893 | skb_set_owner_r(skb, sk); | |
e32123e5 | 894 | NETLINK_CB(skb).sk = ssk; |
cd40b7d3 | 895 | nlk->netlink_rcv(skb); |
bfb253c9 ED |
896 | consume_skb(skb); |
897 | } else { | |
898 | kfree_skb(skb); | |
cd40b7d3 | 899 | } |
cd40b7d3 DL |
900 | sock_put(sk); |
901 | return ret; | |
902 | } | |
903 | ||
904 | int netlink_unicast(struct sock *ssk, struct sk_buff *skb, | |
15e47304 | 905 | u32 portid, int nonblock) |
1da177e4 LT |
906 | { |
907 | struct sock *sk; | |
908 | int err; | |
909 | long timeo; | |
910 | ||
911 | skb = netlink_trim(skb, gfp_any()); | |
912 | ||
913 | timeo = sock_sndtimeo(ssk, nonblock); | |
914 | retry: | |
15e47304 | 915 | sk = netlink_getsockbyportid(ssk, portid); |
1da177e4 LT |
916 | if (IS_ERR(sk)) { |
917 | kfree_skb(skb); | |
918 | return PTR_ERR(sk); | |
919 | } | |
cd40b7d3 | 920 | if (netlink_is_kernel(sk)) |
3fbc2905 | 921 | return netlink_unicast_kernel(sk, skb, ssk); |
cd40b7d3 | 922 | |
b1153f29 | 923 | if (sk_filter(sk, skb)) { |
84874607 | 924 | err = skb->len; |
b1153f29 SH |
925 | kfree_skb(skb); |
926 | sock_put(sk); | |
927 | return err; | |
928 | } | |
929 | ||
9457afee | 930 | err = netlink_attachskb(sk, skb, &timeo, ssk); |
1da177e4 LT |
931 | if (err == 1) |
932 | goto retry; | |
933 | if (err) | |
934 | return err; | |
935 | ||
7ee015e0 | 936 | return netlink_sendskb(sk, skb); |
1da177e4 | 937 | } |
6ac552fd | 938 | EXPORT_SYMBOL(netlink_unicast); |
1da177e4 | 939 | |
4277a083 PM |
940 | int netlink_has_listeners(struct sock *sk, unsigned int group) |
941 | { | |
942 | int res = 0; | |
5c398dc8 | 943 | struct listeners *listeners; |
4277a083 | 944 | |
aed81560 | 945 | BUG_ON(!netlink_is_kernel(sk)); |
b4ff4f04 JB |
946 | |
947 | rcu_read_lock(); | |
948 | listeners = rcu_dereference(nl_table[sk->sk_protocol].listeners); | |
949 | ||
6d772ac5 | 950 | if (listeners && group - 1 < nl_table[sk->sk_protocol].groups) |
5c398dc8 | 951 | res = test_bit(group - 1, listeners->masks); |
b4ff4f04 JB |
952 | |
953 | rcu_read_unlock(); | |
954 | ||
4277a083 PM |
955 | return res; |
956 | } | |
957 | EXPORT_SYMBOL_GPL(netlink_has_listeners); | |
958 | ||
b57ef81f | 959 | static int netlink_broadcast_deliver(struct sock *sk, struct sk_buff *skb) |
1da177e4 LT |
960 | { |
961 | struct netlink_sock *nlk = nlk_sk(sk); | |
962 | ||
963 | if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf && | |
cd967e05 | 964 | !test_bit(NETLINK_CONGESTED, &nlk->state)) { |
1da177e4 | 965 | skb_set_owner_r(skb, sk); |
4a7e7c2a | 966 | __netlink_sendskb(sk, skb); |
2c645800 | 967 | return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1); |
1da177e4 LT |
968 | } |
969 | return -1; | |
970 | } | |
971 | ||
972 | struct netlink_broadcast_data { | |
973 | struct sock *exclude_sk; | |
b4b51029 | 974 | struct net *net; |
15e47304 | 975 | u32 portid; |
1da177e4 LT |
976 | u32 group; |
977 | int failure; | |
ff491a73 | 978 | int delivery_failure; |
1da177e4 LT |
979 | int congested; |
980 | int delivered; | |
7d877f3b | 981 | gfp_t allocation; |
1da177e4 | 982 | struct sk_buff *skb, *skb2; |
910a7e90 EB |
983 | int (*tx_filter)(struct sock *dsk, struct sk_buff *skb, void *data); |
984 | void *tx_data; | |
1da177e4 LT |
985 | }; |
986 | ||
b57ef81f | 987 | static int do_one_broadcast(struct sock *sk, |
1da177e4 LT |
988 | struct netlink_broadcast_data *p) |
989 | { | |
990 | struct netlink_sock *nlk = nlk_sk(sk); | |
991 | int val; | |
992 | ||
993 | if (p->exclude_sk == sk) | |
994 | goto out; | |
995 | ||
15e47304 | 996 | if (nlk->portid == p->portid || p->group - 1 >= nlk->ngroups || |
f7fa9b10 | 997 | !test_bit(p->group - 1, nlk->groups)) |
1da177e4 LT |
998 | goto out; |
999 | ||
878628fb | 1000 | if (!net_eq(sock_net(sk), p->net)) |
b4b51029 EB |
1001 | goto out; |
1002 | ||
1da177e4 LT |
1003 | if (p->failure) { |
1004 | netlink_overrun(sk); | |
1005 | goto out; | |
1006 | } | |
1007 | ||
1008 | sock_hold(sk); | |
1009 | if (p->skb2 == NULL) { | |
68acc024 | 1010 | if (skb_shared(p->skb)) { |
1da177e4 LT |
1011 | p->skb2 = skb_clone(p->skb, p->allocation); |
1012 | } else { | |
68acc024 TC |
1013 | p->skb2 = skb_get(p->skb); |
1014 | /* | |
1015 | * skb ownership may have been set when | |
1016 | * delivered to a previous socket. | |
1017 | */ | |
1018 | skb_orphan(p->skb2); | |
1da177e4 LT |
1019 | } |
1020 | } | |
1021 | if (p->skb2 == NULL) { | |
1022 | netlink_overrun(sk); | |
1023 | /* Clone failed. Notify ALL listeners. */ | |
1024 | p->failure = 1; | |
be0c22a4 PNA |
1025 | if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR) |
1026 | p->delivery_failure = 1; | |
910a7e90 EB |
1027 | } else if (p->tx_filter && p->tx_filter(sk, p->skb2, p->tx_data)) { |
1028 | kfree_skb(p->skb2); | |
1029 | p->skb2 = NULL; | |
b1153f29 SH |
1030 | } else if (sk_filter(sk, p->skb2)) { |
1031 | kfree_skb(p->skb2); | |
1032 | p->skb2 = NULL; | |
1da177e4 LT |
1033 | } else if ((val = netlink_broadcast_deliver(sk, p->skb2)) < 0) { |
1034 | netlink_overrun(sk); | |
be0c22a4 PNA |
1035 | if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR) |
1036 | p->delivery_failure = 1; | |
1da177e4 LT |
1037 | } else { |
1038 | p->congested |= val; | |
1039 | p->delivered = 1; | |
1040 | p->skb2 = NULL; | |
1041 | } | |
1042 | sock_put(sk); | |
1043 | ||
1044 | out: | |
1045 | return 0; | |
1046 | } | |
1047 | ||
15e47304 | 1048 | int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb, u32 portid, |
910a7e90 EB |
1049 | u32 group, gfp_t allocation, |
1050 | int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data), | |
1051 | void *filter_data) | |
1da177e4 | 1052 | { |
3b1e0a65 | 1053 | struct net *net = sock_net(ssk); |
1da177e4 | 1054 | struct netlink_broadcast_data info; |
1da177e4 LT |
1055 | struct sock *sk; |
1056 | ||
1057 | skb = netlink_trim(skb, allocation); | |
1058 | ||
1059 | info.exclude_sk = ssk; | |
b4b51029 | 1060 | info.net = net; |
15e47304 | 1061 | info.portid = portid; |
1da177e4 LT |
1062 | info.group = group; |
1063 | info.failure = 0; | |
ff491a73 | 1064 | info.delivery_failure = 0; |
1da177e4 LT |
1065 | info.congested = 0; |
1066 | info.delivered = 0; | |
1067 | info.allocation = allocation; | |
1068 | info.skb = skb; | |
1069 | info.skb2 = NULL; | |
910a7e90 EB |
1070 | info.tx_filter = filter; |
1071 | info.tx_data = filter_data; | |
1da177e4 LT |
1072 | |
1073 | /* While we sleep in clone, do not allow to change socket list */ | |
1074 | ||
1075 | netlink_lock_table(); | |
1076 | ||
b67bfe0d | 1077 | sk_for_each_bound(sk, &nl_table[ssk->sk_protocol].mc_list) |
1da177e4 LT |
1078 | do_one_broadcast(sk, &info); |
1079 | ||
70d4bf6d | 1080 | consume_skb(skb); |
aa1c6a6f | 1081 | |
1da177e4 LT |
1082 | netlink_unlock_table(); |
1083 | ||
70d4bf6d NH |
1084 | if (info.delivery_failure) { |
1085 | kfree_skb(info.skb2); | |
ff491a73 | 1086 | return -ENOBUFS; |
658cb354 ED |
1087 | } |
1088 | consume_skb(info.skb2); | |
ff491a73 | 1089 | |
1da177e4 LT |
1090 | if (info.delivered) { |
1091 | if (info.congested && (allocation & __GFP_WAIT)) | |
1092 | yield(); | |
1093 | return 0; | |
1094 | } | |
1da177e4 LT |
1095 | return -ESRCH; |
1096 | } | |
910a7e90 EB |
1097 | EXPORT_SYMBOL(netlink_broadcast_filtered); |
1098 | ||
15e47304 | 1099 | int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 portid, |
910a7e90 EB |
1100 | u32 group, gfp_t allocation) |
1101 | { | |
15e47304 | 1102 | return netlink_broadcast_filtered(ssk, skb, portid, group, allocation, |
910a7e90 EB |
1103 | NULL, NULL); |
1104 | } | |
6ac552fd | 1105 | EXPORT_SYMBOL(netlink_broadcast); |
1da177e4 LT |
1106 | |
1107 | struct netlink_set_err_data { | |
1108 | struct sock *exclude_sk; | |
15e47304 | 1109 | u32 portid; |
1da177e4 LT |
1110 | u32 group; |
1111 | int code; | |
1112 | }; | |
1113 | ||
b57ef81f | 1114 | static int do_one_set_err(struct sock *sk, struct netlink_set_err_data *p) |
1da177e4 LT |
1115 | { |
1116 | struct netlink_sock *nlk = nlk_sk(sk); | |
1a50307b | 1117 | int ret = 0; |
1da177e4 LT |
1118 | |
1119 | if (sk == p->exclude_sk) | |
1120 | goto out; | |
1121 | ||
09ad9bc7 | 1122 | if (!net_eq(sock_net(sk), sock_net(p->exclude_sk))) |
b4b51029 EB |
1123 | goto out; |
1124 | ||
15e47304 | 1125 | if (nlk->portid == p->portid || p->group - 1 >= nlk->ngroups || |
f7fa9b10 | 1126 | !test_bit(p->group - 1, nlk->groups)) |
1da177e4 LT |
1127 | goto out; |
1128 | ||
1a50307b PNA |
1129 | if (p->code == ENOBUFS && nlk->flags & NETLINK_RECV_NO_ENOBUFS) { |
1130 | ret = 1; | |
1131 | goto out; | |
1132 | } | |
1133 | ||
1da177e4 LT |
1134 | sk->sk_err = p->code; |
1135 | sk->sk_error_report(sk); | |
1136 | out: | |
1a50307b | 1137 | return ret; |
1da177e4 LT |
1138 | } |
1139 | ||
4843b93c PNA |
1140 | /** |
1141 | * netlink_set_err - report error to broadcast listeners | |
1142 | * @ssk: the kernel netlink socket, as returned by netlink_kernel_create() | |
15e47304 | 1143 | * @portid: the PORTID of a process that we want to skip (if any) |
4843b93c PNA |
1144 | * @groups: the broadcast group that will notice the error |
1145 | * @code: error code, must be negative (as usual in kernelspace) | |
1a50307b PNA |
1146 | * |
1147 | * This function returns the number of broadcast listeners that have set the | |
1148 | * NETLINK_RECV_NO_ENOBUFS socket option. | |
4843b93c | 1149 | */ |
15e47304 | 1150 | int netlink_set_err(struct sock *ssk, u32 portid, u32 group, int code) |
1da177e4 LT |
1151 | { |
1152 | struct netlink_set_err_data info; | |
1da177e4 | 1153 | struct sock *sk; |
1a50307b | 1154 | int ret = 0; |
1da177e4 LT |
1155 | |
1156 | info.exclude_sk = ssk; | |
15e47304 | 1157 | info.portid = portid; |
1da177e4 | 1158 | info.group = group; |
4843b93c PNA |
1159 | /* sk->sk_err wants a positive error value */ |
1160 | info.code = -code; | |
1da177e4 LT |
1161 | |
1162 | read_lock(&nl_table_lock); | |
1163 | ||
b67bfe0d | 1164 | sk_for_each_bound(sk, &nl_table[ssk->sk_protocol].mc_list) |
1a50307b | 1165 | ret += do_one_set_err(sk, &info); |
1da177e4 LT |
1166 | |
1167 | read_unlock(&nl_table_lock); | |
1a50307b | 1168 | return ret; |
1da177e4 | 1169 | } |
dd5b6ce6 | 1170 | EXPORT_SYMBOL(netlink_set_err); |
1da177e4 | 1171 | |
84659eb5 JB |
1172 | /* must be called with netlink table grabbed */ |
1173 | static void netlink_update_socket_mc(struct netlink_sock *nlk, | |
1174 | unsigned int group, | |
1175 | int is_new) | |
1176 | { | |
1177 | int old, new = !!is_new, subscriptions; | |
1178 | ||
1179 | old = test_bit(group - 1, nlk->groups); | |
1180 | subscriptions = nlk->subscriptions - old + new; | |
1181 | if (new) | |
1182 | __set_bit(group - 1, nlk->groups); | |
1183 | else | |
1184 | __clear_bit(group - 1, nlk->groups); | |
1185 | netlink_update_subscriptions(&nlk->sk, subscriptions); | |
1186 | netlink_update_listeners(&nlk->sk); | |
1187 | } | |
1188 | ||
9a4595bc | 1189 | static int netlink_setsockopt(struct socket *sock, int level, int optname, |
b7058842 | 1190 | char __user *optval, unsigned int optlen) |
9a4595bc PM |
1191 | { |
1192 | struct sock *sk = sock->sk; | |
1193 | struct netlink_sock *nlk = nlk_sk(sk); | |
eb496534 JB |
1194 | unsigned int val = 0; |
1195 | int err; | |
9a4595bc PM |
1196 | |
1197 | if (level != SOL_NETLINK) | |
1198 | return -ENOPROTOOPT; | |
1199 | ||
1200 | if (optlen >= sizeof(int) && | |
eb496534 | 1201 | get_user(val, (unsigned int __user *)optval)) |
9a4595bc PM |
1202 | return -EFAULT; |
1203 | ||
1204 | switch (optname) { | |
1205 | case NETLINK_PKTINFO: | |
1206 | if (val) | |
1207 | nlk->flags |= NETLINK_RECV_PKTINFO; | |
1208 | else | |
1209 | nlk->flags &= ~NETLINK_RECV_PKTINFO; | |
1210 | err = 0; | |
1211 | break; | |
1212 | case NETLINK_ADD_MEMBERSHIP: | |
1213 | case NETLINK_DROP_MEMBERSHIP: { | |
9785e10a | 1214 | if (!netlink_capable(sock, NL_CFG_F_NONROOT_RECV)) |
9a4595bc | 1215 | return -EPERM; |
b4ff4f04 JB |
1216 | err = netlink_realloc_groups(sk); |
1217 | if (err) | |
1218 | return err; | |
9a4595bc PM |
1219 | if (!val || val - 1 >= nlk->ngroups) |
1220 | return -EINVAL; | |
1221 | netlink_table_grab(); | |
84659eb5 JB |
1222 | netlink_update_socket_mc(nlk, val, |
1223 | optname == NETLINK_ADD_MEMBERSHIP); | |
9a4595bc | 1224 | netlink_table_ungrab(); |
03292745 PNA |
1225 | |
1226 | if (nlk->netlink_bind) | |
1227 | nlk->netlink_bind(val); | |
1228 | ||
9a4595bc PM |
1229 | err = 0; |
1230 | break; | |
1231 | } | |
be0c22a4 PNA |
1232 | case NETLINK_BROADCAST_ERROR: |
1233 | if (val) | |
1234 | nlk->flags |= NETLINK_BROADCAST_SEND_ERROR; | |
1235 | else | |
1236 | nlk->flags &= ~NETLINK_BROADCAST_SEND_ERROR; | |
1237 | err = 0; | |
1238 | break; | |
38938bfe PNA |
1239 | case NETLINK_NO_ENOBUFS: |
1240 | if (val) { | |
1241 | nlk->flags |= NETLINK_RECV_NO_ENOBUFS; | |
cd967e05 | 1242 | clear_bit(NETLINK_CONGESTED, &nlk->state); |
38938bfe | 1243 | wake_up_interruptible(&nlk->wait); |
658cb354 | 1244 | } else { |
38938bfe | 1245 | nlk->flags &= ~NETLINK_RECV_NO_ENOBUFS; |
658cb354 | 1246 | } |
38938bfe PNA |
1247 | err = 0; |
1248 | break; | |
9a4595bc PM |
1249 | default: |
1250 | err = -ENOPROTOOPT; | |
1251 | } | |
1252 | return err; | |
1253 | } | |
1254 | ||
1255 | static int netlink_getsockopt(struct socket *sock, int level, int optname, | |
746fac4d | 1256 | char __user *optval, int __user *optlen) |
9a4595bc PM |
1257 | { |
1258 | struct sock *sk = sock->sk; | |
1259 | struct netlink_sock *nlk = nlk_sk(sk); | |
1260 | int len, val, err; | |
1261 | ||
1262 | if (level != SOL_NETLINK) | |
1263 | return -ENOPROTOOPT; | |
1264 | ||
1265 | if (get_user(len, optlen)) | |
1266 | return -EFAULT; | |
1267 | if (len < 0) | |
1268 | return -EINVAL; | |
1269 | ||
1270 | switch (optname) { | |
1271 | case NETLINK_PKTINFO: | |
1272 | if (len < sizeof(int)) | |
1273 | return -EINVAL; | |
1274 | len = sizeof(int); | |
1275 | val = nlk->flags & NETLINK_RECV_PKTINFO ? 1 : 0; | |
a27b58fe HC |
1276 | if (put_user(len, optlen) || |
1277 | put_user(val, optval)) | |
1278 | return -EFAULT; | |
9a4595bc PM |
1279 | err = 0; |
1280 | break; | |
be0c22a4 PNA |
1281 | case NETLINK_BROADCAST_ERROR: |
1282 | if (len < sizeof(int)) | |
1283 | return -EINVAL; | |
1284 | len = sizeof(int); | |
1285 | val = nlk->flags & NETLINK_BROADCAST_SEND_ERROR ? 1 : 0; | |
1286 | if (put_user(len, optlen) || | |
1287 | put_user(val, optval)) | |
1288 | return -EFAULT; | |
1289 | err = 0; | |
1290 | break; | |
38938bfe PNA |
1291 | case NETLINK_NO_ENOBUFS: |
1292 | if (len < sizeof(int)) | |
1293 | return -EINVAL; | |
1294 | len = sizeof(int); | |
1295 | val = nlk->flags & NETLINK_RECV_NO_ENOBUFS ? 1 : 0; | |
1296 | if (put_user(len, optlen) || | |
1297 | put_user(val, optval)) | |
1298 | return -EFAULT; | |
1299 | err = 0; | |
1300 | break; | |
9a4595bc PM |
1301 | default: |
1302 | err = -ENOPROTOOPT; | |
1303 | } | |
1304 | return err; | |
1305 | } | |
1306 | ||
1307 | static void netlink_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb) | |
1308 | { | |
1309 | struct nl_pktinfo info; | |
1310 | ||
1311 | info.group = NETLINK_CB(skb).dst_group; | |
1312 | put_cmsg(msg, SOL_NETLINK, NETLINK_PKTINFO, sizeof(info), &info); | |
1313 | } | |
1314 | ||
1da177e4 LT |
1315 | static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock, |
1316 | struct msghdr *msg, size_t len) | |
1317 | { | |
1318 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1319 | struct sock *sk = sock->sk; | |
1320 | struct netlink_sock *nlk = nlk_sk(sk); | |
6ac552fd | 1321 | struct sockaddr_nl *addr = msg->msg_name; |
15e47304 | 1322 | u32 dst_portid; |
d629b836 | 1323 | u32 dst_group; |
1da177e4 LT |
1324 | struct sk_buff *skb; |
1325 | int err; | |
1326 | struct scm_cookie scm; | |
1327 | ||
1328 | if (msg->msg_flags&MSG_OOB) | |
1329 | return -EOPNOTSUPP; | |
1330 | ||
16e57262 | 1331 | if (NULL == siocb->scm) |
1da177e4 | 1332 | siocb->scm = &scm; |
16e57262 | 1333 | |
e0e3cea4 | 1334 | err = scm_send(sock, msg, siocb->scm, true); |
1da177e4 LT |
1335 | if (err < 0) |
1336 | return err; | |
1337 | ||
1338 | if (msg->msg_namelen) { | |
b47030c7 | 1339 | err = -EINVAL; |
1da177e4 | 1340 | if (addr->nl_family != AF_NETLINK) |
b47030c7 | 1341 | goto out; |
15e47304 | 1342 | dst_portid = addr->nl_pid; |
d629b836 | 1343 | dst_group = ffs(addr->nl_groups); |
b47030c7 | 1344 | err = -EPERM; |
15e47304 | 1345 | if ((dst_group || dst_portid) && |
9785e10a | 1346 | !netlink_capable(sock, NL_CFG_F_NONROOT_SEND)) |
b47030c7 | 1347 | goto out; |
1da177e4 | 1348 | } else { |
15e47304 | 1349 | dst_portid = nlk->dst_portid; |
d629b836 | 1350 | dst_group = nlk->dst_group; |
1da177e4 LT |
1351 | } |
1352 | ||
15e47304 | 1353 | if (!nlk->portid) { |
1da177e4 LT |
1354 | err = netlink_autobind(sock); |
1355 | if (err) | |
1356 | goto out; | |
1357 | } | |
1358 | ||
1359 | err = -EMSGSIZE; | |
1360 | if (len > sk->sk_sndbuf - 32) | |
1361 | goto out; | |
1362 | err = -ENOBUFS; | |
339bf98f | 1363 | skb = alloc_skb(len, GFP_KERNEL); |
6ac552fd | 1364 | if (skb == NULL) |
1da177e4 LT |
1365 | goto out; |
1366 | ||
15e47304 | 1367 | NETLINK_CB(skb).portid = nlk->portid; |
d629b836 | 1368 | NETLINK_CB(skb).dst_group = dst_group; |
dbe9a417 | 1369 | NETLINK_CB(skb).creds = siocb->scm->creds; |
1da177e4 | 1370 | |
1da177e4 | 1371 | err = -EFAULT; |
6ac552fd | 1372 | if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) { |
1da177e4 LT |
1373 | kfree_skb(skb); |
1374 | goto out; | |
1375 | } | |
1376 | ||
1377 | err = security_netlink_send(sk, skb); | |
1378 | if (err) { | |
1379 | kfree_skb(skb); | |
1380 | goto out; | |
1381 | } | |
1382 | ||
d629b836 | 1383 | if (dst_group) { |
1da177e4 | 1384 | atomic_inc(&skb->users); |
15e47304 | 1385 | netlink_broadcast(sk, skb, dst_portid, dst_group, GFP_KERNEL); |
1da177e4 | 1386 | } |
15e47304 | 1387 | err = netlink_unicast(sk, skb, dst_portid, msg->msg_flags&MSG_DONTWAIT); |
1da177e4 LT |
1388 | |
1389 | out: | |
b47030c7 | 1390 | scm_destroy(siocb->scm); |
1da177e4 LT |
1391 | return err; |
1392 | } | |
1393 | ||
1394 | static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock, | |
1395 | struct msghdr *msg, size_t len, | |
1396 | int flags) | |
1397 | { | |
1398 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1399 | struct scm_cookie scm; | |
1400 | struct sock *sk = sock->sk; | |
1401 | struct netlink_sock *nlk = nlk_sk(sk); | |
1402 | int noblock = flags&MSG_DONTWAIT; | |
1403 | size_t copied; | |
68d6ac6d | 1404 | struct sk_buff *skb, *data_skb; |
b44d211e | 1405 | int err, ret; |
1da177e4 LT |
1406 | |
1407 | if (flags&MSG_OOB) | |
1408 | return -EOPNOTSUPP; | |
1409 | ||
1410 | copied = 0; | |
1411 | ||
6ac552fd PM |
1412 | skb = skb_recv_datagram(sk, flags, noblock, &err); |
1413 | if (skb == NULL) | |
1da177e4 LT |
1414 | goto out; |
1415 | ||
68d6ac6d JB |
1416 | data_skb = skb; |
1417 | ||
1dacc76d JB |
1418 | #ifdef CONFIG_COMPAT_NETLINK_MESSAGES |
1419 | if (unlikely(skb_shinfo(skb)->frag_list)) { | |
1dacc76d | 1420 | /* |
68d6ac6d JB |
1421 | * If this skb has a frag_list, then here that means that we |
1422 | * will have to use the frag_list skb's data for compat tasks | |
1423 | * and the regular skb's data for normal (non-compat) tasks. | |
1dacc76d | 1424 | * |
68d6ac6d JB |
1425 | * If we need to send the compat skb, assign it to the |
1426 | * 'data_skb' variable so that it will be used below for data | |
1427 | * copying. We keep 'skb' for everything else, including | |
1428 | * freeing both later. | |
1dacc76d | 1429 | */ |
68d6ac6d JB |
1430 | if (flags & MSG_CMSG_COMPAT) |
1431 | data_skb = skb_shinfo(skb)->frag_list; | |
1dacc76d JB |
1432 | } |
1433 | #endif | |
1434 | ||
1da177e4 LT |
1435 | msg->msg_namelen = 0; |
1436 | ||
68d6ac6d | 1437 | copied = data_skb->len; |
1da177e4 LT |
1438 | if (len < copied) { |
1439 | msg->msg_flags |= MSG_TRUNC; | |
1440 | copied = len; | |
1441 | } | |
1442 | ||
68d6ac6d JB |
1443 | skb_reset_transport_header(data_skb); |
1444 | err = skb_copy_datagram_iovec(data_skb, 0, msg->msg_iov, copied); | |
1da177e4 LT |
1445 | |
1446 | if (msg->msg_name) { | |
6ac552fd | 1447 | struct sockaddr_nl *addr = (struct sockaddr_nl *)msg->msg_name; |
1da177e4 LT |
1448 | addr->nl_family = AF_NETLINK; |
1449 | addr->nl_pad = 0; | |
15e47304 | 1450 | addr->nl_pid = NETLINK_CB(skb).portid; |
d629b836 | 1451 | addr->nl_groups = netlink_group_mask(NETLINK_CB(skb).dst_group); |
1da177e4 LT |
1452 | msg->msg_namelen = sizeof(*addr); |
1453 | } | |
1454 | ||
cc9a06cd PM |
1455 | if (nlk->flags & NETLINK_RECV_PKTINFO) |
1456 | netlink_cmsg_recv_pktinfo(msg, skb); | |
1457 | ||
1da177e4 LT |
1458 | if (NULL == siocb->scm) { |
1459 | memset(&scm, 0, sizeof(scm)); | |
1460 | siocb->scm = &scm; | |
1461 | } | |
1462 | siocb->scm->creds = *NETLINK_CREDS(skb); | |
188ccb55 | 1463 | if (flags & MSG_TRUNC) |
68d6ac6d | 1464 | copied = data_skb->len; |
daa3766e | 1465 | |
1da177e4 LT |
1466 | skb_free_datagram(sk, skb); |
1467 | ||
b44d211e AV |
1468 | if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) { |
1469 | ret = netlink_dump(sk); | |
1470 | if (ret) { | |
1471 | sk->sk_err = ret; | |
1472 | sk->sk_error_report(sk); | |
1473 | } | |
1474 | } | |
1da177e4 LT |
1475 | |
1476 | scm_recv(sock, msg, siocb->scm, flags); | |
1da177e4 LT |
1477 | out: |
1478 | netlink_rcv_wake(sk); | |
1479 | return err ? : copied; | |
1480 | } | |
1481 | ||
1482 | static void netlink_data_ready(struct sock *sk, int len) | |
1483 | { | |
cd40b7d3 | 1484 | BUG(); |
1da177e4 LT |
1485 | } |
1486 | ||
1487 | /* | |
746fac4d | 1488 | * We export these functions to other modules. They provide a |
1da177e4 LT |
1489 | * complete set of kernel non-blocking support for message |
1490 | * queueing. | |
1491 | */ | |
1492 | ||
1493 | struct sock * | |
9f00d977 PNA |
1494 | __netlink_kernel_create(struct net *net, int unit, struct module *module, |
1495 | struct netlink_kernel_cfg *cfg) | |
1da177e4 LT |
1496 | { |
1497 | struct socket *sock; | |
1498 | struct sock *sk; | |
77247bbb | 1499 | struct netlink_sock *nlk; |
5c398dc8 | 1500 | struct listeners *listeners = NULL; |
a31f2d17 PNA |
1501 | struct mutex *cb_mutex = cfg ? cfg->cb_mutex : NULL; |
1502 | unsigned int groups; | |
1da177e4 | 1503 | |
fab2caf6 | 1504 | BUG_ON(!nl_table); |
1da177e4 | 1505 | |
6ac552fd | 1506 | if (unit < 0 || unit >= MAX_LINKS) |
1da177e4 LT |
1507 | return NULL; |
1508 | ||
1509 | if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock)) | |
1510 | return NULL; | |
1511 | ||
23fe1866 PE |
1512 | /* |
1513 | * We have to just have a reference on the net from sk, but don't | |
1514 | * get_net it. Besides, we cannot get and then put the net here. | |
1515 | * So we create one inside init_net and the move it to net. | |
1516 | */ | |
1517 | ||
1518 | if (__netlink_create(&init_net, sock, cb_mutex, unit) < 0) | |
1519 | goto out_sock_release_nosk; | |
1520 | ||
1521 | sk = sock->sk; | |
edf02087 | 1522 | sk_change_net(sk, net); |
4fdb3bb7 | 1523 | |
a31f2d17 | 1524 | if (!cfg || cfg->groups < 32) |
4277a083 | 1525 | groups = 32; |
a31f2d17 PNA |
1526 | else |
1527 | groups = cfg->groups; | |
4277a083 | 1528 | |
5c398dc8 | 1529 | listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL); |
4277a083 PM |
1530 | if (!listeners) |
1531 | goto out_sock_release; | |
1532 | ||
1da177e4 | 1533 | sk->sk_data_ready = netlink_data_ready; |
a31f2d17 PNA |
1534 | if (cfg && cfg->input) |
1535 | nlk_sk(sk)->netlink_rcv = cfg->input; | |
1da177e4 | 1536 | |
b4b51029 | 1537 | if (netlink_insert(sk, net, 0)) |
77247bbb | 1538 | goto out_sock_release; |
4fdb3bb7 | 1539 | |
77247bbb PM |
1540 | nlk = nlk_sk(sk); |
1541 | nlk->flags |= NETLINK_KERNEL_SOCKET; | |
4fdb3bb7 | 1542 | |
4fdb3bb7 | 1543 | netlink_table_grab(); |
b4b51029 EB |
1544 | if (!nl_table[unit].registered) { |
1545 | nl_table[unit].groups = groups; | |
5c398dc8 | 1546 | rcu_assign_pointer(nl_table[unit].listeners, listeners); |
b4b51029 EB |
1547 | nl_table[unit].cb_mutex = cb_mutex; |
1548 | nl_table[unit].module = module; | |
9785e10a PNA |
1549 | if (cfg) { |
1550 | nl_table[unit].bind = cfg->bind; | |
1551 | nl_table[unit].flags = cfg->flags; | |
1552 | } | |
b4b51029 | 1553 | nl_table[unit].registered = 1; |
f937f1f4 JJ |
1554 | } else { |
1555 | kfree(listeners); | |
869e58f8 | 1556 | nl_table[unit].registered++; |
b4b51029 | 1557 | } |
4fdb3bb7 | 1558 | netlink_table_ungrab(); |
77247bbb PM |
1559 | return sk; |
1560 | ||
4fdb3bb7 | 1561 | out_sock_release: |
4277a083 | 1562 | kfree(listeners); |
9dfbec1f | 1563 | netlink_kernel_release(sk); |
23fe1866 PE |
1564 | return NULL; |
1565 | ||
1566 | out_sock_release_nosk: | |
4fdb3bb7 | 1567 | sock_release(sock); |
77247bbb | 1568 | return NULL; |
1da177e4 | 1569 | } |
9f00d977 | 1570 | EXPORT_SYMBOL(__netlink_kernel_create); |
b7c6ba6e DL |
1571 | |
1572 | void | |
1573 | netlink_kernel_release(struct sock *sk) | |
1574 | { | |
edf02087 | 1575 | sk_release_kernel(sk); |
b7c6ba6e DL |
1576 | } |
1577 | EXPORT_SYMBOL(netlink_kernel_release); | |
1578 | ||
d136f1bd | 1579 | int __netlink_change_ngroups(struct sock *sk, unsigned int groups) |
b4ff4f04 | 1580 | { |
5c398dc8 | 1581 | struct listeners *new, *old; |
b4ff4f04 | 1582 | struct netlink_table *tbl = &nl_table[sk->sk_protocol]; |
b4ff4f04 JB |
1583 | |
1584 | if (groups < 32) | |
1585 | groups = 32; | |
1586 | ||
b4ff4f04 | 1587 | if (NLGRPSZ(tbl->groups) < NLGRPSZ(groups)) { |
5c398dc8 ED |
1588 | new = kzalloc(sizeof(*new) + NLGRPSZ(groups), GFP_ATOMIC); |
1589 | if (!new) | |
d136f1bd | 1590 | return -ENOMEM; |
6d772ac5 | 1591 | old = nl_deref_protected(tbl->listeners); |
5c398dc8 ED |
1592 | memcpy(new->masks, old->masks, NLGRPSZ(tbl->groups)); |
1593 | rcu_assign_pointer(tbl->listeners, new); | |
1594 | ||
37b6b935 | 1595 | kfree_rcu(old, rcu); |
b4ff4f04 JB |
1596 | } |
1597 | tbl->groups = groups; | |
1598 | ||
d136f1bd JB |
1599 | return 0; |
1600 | } | |
1601 | ||
1602 | /** | |
1603 | * netlink_change_ngroups - change number of multicast groups | |
1604 | * | |
1605 | * This changes the number of multicast groups that are available | |
1606 | * on a certain netlink family. Note that it is not possible to | |
1607 | * change the number of groups to below 32. Also note that it does | |
1608 | * not implicitly call netlink_clear_multicast_users() when the | |
1609 | * number of groups is reduced. | |
1610 | * | |
1611 | * @sk: The kernel netlink socket, as returned by netlink_kernel_create(). | |
1612 | * @groups: The new number of groups. | |
1613 | */ | |
1614 | int netlink_change_ngroups(struct sock *sk, unsigned int groups) | |
1615 | { | |
1616 | int err; | |
1617 | ||
1618 | netlink_table_grab(); | |
1619 | err = __netlink_change_ngroups(sk, groups); | |
b4ff4f04 | 1620 | netlink_table_ungrab(); |
d136f1bd | 1621 | |
b4ff4f04 JB |
1622 | return err; |
1623 | } | |
b4ff4f04 | 1624 | |
b8273570 JB |
1625 | void __netlink_clear_multicast_users(struct sock *ksk, unsigned int group) |
1626 | { | |
1627 | struct sock *sk; | |
b8273570 JB |
1628 | struct netlink_table *tbl = &nl_table[ksk->sk_protocol]; |
1629 | ||
b67bfe0d | 1630 | sk_for_each_bound(sk, &tbl->mc_list) |
b8273570 JB |
1631 | netlink_update_socket_mc(nlk_sk(sk), group, 0); |
1632 | } | |
1633 | ||
84659eb5 JB |
1634 | /** |
1635 | * netlink_clear_multicast_users - kick off multicast listeners | |
1636 | * | |
1637 | * This function removes all listeners from the given group. | |
1638 | * @ksk: The kernel netlink socket, as returned by | |
1639 | * netlink_kernel_create(). | |
1640 | * @group: The multicast group to clear. | |
1641 | */ | |
1642 | void netlink_clear_multicast_users(struct sock *ksk, unsigned int group) | |
1643 | { | |
84659eb5 | 1644 | netlink_table_grab(); |
b8273570 | 1645 | __netlink_clear_multicast_users(ksk, group); |
84659eb5 JB |
1646 | netlink_table_ungrab(); |
1647 | } | |
84659eb5 | 1648 | |
a46621a3 | 1649 | struct nlmsghdr * |
15e47304 | 1650 | __nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int flags) |
a46621a3 DV |
1651 | { |
1652 | struct nlmsghdr *nlh; | |
573ce260 | 1653 | int size = nlmsg_msg_size(len); |
a46621a3 DV |
1654 | |
1655 | nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size)); | |
1656 | nlh->nlmsg_type = type; | |
1657 | nlh->nlmsg_len = size; | |
1658 | nlh->nlmsg_flags = flags; | |
15e47304 | 1659 | nlh->nlmsg_pid = portid; |
a46621a3 DV |
1660 | nlh->nlmsg_seq = seq; |
1661 | if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0) | |
573ce260 | 1662 | memset(nlmsg_data(nlh) + len, 0, NLMSG_ALIGN(size) - size); |
a46621a3 DV |
1663 | return nlh; |
1664 | } | |
1665 | EXPORT_SYMBOL(__nlmsg_put); | |
1666 | ||
1da177e4 LT |
1667 | /* |
1668 | * It looks a bit ugly. | |
1669 | * It would be better to create kernel thread. | |
1670 | */ | |
1671 | ||
1672 | static int netlink_dump(struct sock *sk) | |
1673 | { | |
1674 | struct netlink_sock *nlk = nlk_sk(sk); | |
1675 | struct netlink_callback *cb; | |
c7ac8679 | 1676 | struct sk_buff *skb = NULL; |
1da177e4 | 1677 | struct nlmsghdr *nlh; |
bf8b79e4 | 1678 | int len, err = -ENOBUFS; |
c7ac8679 | 1679 | int alloc_size; |
1da177e4 | 1680 | |
af65bdfc | 1681 | mutex_lock(nlk->cb_mutex); |
1da177e4 LT |
1682 | |
1683 | cb = nlk->cb; | |
1684 | if (cb == NULL) { | |
bf8b79e4 TG |
1685 | err = -EINVAL; |
1686 | goto errout_skb; | |
1da177e4 LT |
1687 | } |
1688 | ||
c7ac8679 GR |
1689 | alloc_size = max_t(int, cb->min_dump_alloc, NLMSG_GOODSIZE); |
1690 | ||
1691 | skb = sock_rmalloc(sk, alloc_size, 0, GFP_KERNEL); | |
1692 | if (!skb) | |
c63d6ea3 | 1693 | goto errout_skb; |
c7ac8679 | 1694 | |
1da177e4 LT |
1695 | len = cb->dump(skb, cb); |
1696 | ||
1697 | if (len > 0) { | |
af65bdfc | 1698 | mutex_unlock(nlk->cb_mutex); |
b1153f29 SH |
1699 | |
1700 | if (sk_filter(sk, skb)) | |
1701 | kfree_skb(skb); | |
4a7e7c2a ED |
1702 | else |
1703 | __netlink_sendskb(sk, skb); | |
1da177e4 LT |
1704 | return 0; |
1705 | } | |
1706 | ||
bf8b79e4 TG |
1707 | nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI); |
1708 | if (!nlh) | |
1709 | goto errout_skb; | |
1710 | ||
670dc283 JB |
1711 | nl_dump_check_consistent(cb, nlh); |
1712 | ||
bf8b79e4 TG |
1713 | memcpy(nlmsg_data(nlh), &len, sizeof(len)); |
1714 | ||
b1153f29 SH |
1715 | if (sk_filter(sk, skb)) |
1716 | kfree_skb(skb); | |
4a7e7c2a ED |
1717 | else |
1718 | __netlink_sendskb(sk, skb); | |
1da177e4 | 1719 | |
a8f74b22 TG |
1720 | if (cb->done) |
1721 | cb->done(cb); | |
1da177e4 | 1722 | nlk->cb = NULL; |
af65bdfc | 1723 | mutex_unlock(nlk->cb_mutex); |
1da177e4 | 1724 | |
6dc878a8 | 1725 | module_put(cb->module); |
bfb253c9 | 1726 | netlink_consume_callback(cb); |
1da177e4 | 1727 | return 0; |
1797754e | 1728 | |
bf8b79e4 | 1729 | errout_skb: |
af65bdfc | 1730 | mutex_unlock(nlk->cb_mutex); |
bf8b79e4 | 1731 | kfree_skb(skb); |
bf8b79e4 | 1732 | return err; |
1da177e4 LT |
1733 | } |
1734 | ||
6dc878a8 G |
1735 | int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb, |
1736 | const struct nlmsghdr *nlh, | |
1737 | struct netlink_dump_control *control) | |
1da177e4 LT |
1738 | { |
1739 | struct netlink_callback *cb; | |
1740 | struct sock *sk; | |
1741 | struct netlink_sock *nlk; | |
b44d211e | 1742 | int ret; |
1da177e4 | 1743 | |
0da974f4 | 1744 | cb = kzalloc(sizeof(*cb), GFP_KERNEL); |
1da177e4 LT |
1745 | if (cb == NULL) |
1746 | return -ENOBUFS; | |
1747 | ||
80d326fa PNA |
1748 | cb->dump = control->dump; |
1749 | cb->done = control->done; | |
1da177e4 | 1750 | cb->nlh = nlh; |
7175c883 | 1751 | cb->data = control->data; |
6dc878a8 | 1752 | cb->module = control->module; |
80d326fa | 1753 | cb->min_dump_alloc = control->min_dump_alloc; |
1da177e4 LT |
1754 | atomic_inc(&skb->users); |
1755 | cb->skb = skb; | |
1756 | ||
15e47304 | 1757 | sk = netlink_lookup(sock_net(ssk), ssk->sk_protocol, NETLINK_CB(skb).portid); |
1da177e4 LT |
1758 | if (sk == NULL) { |
1759 | netlink_destroy_callback(cb); | |
1760 | return -ECONNREFUSED; | |
1761 | } | |
1762 | nlk = nlk_sk(sk); | |
6dc878a8 | 1763 | |
af65bdfc | 1764 | mutex_lock(nlk->cb_mutex); |
6dc878a8 | 1765 | /* A dump is in progress... */ |
3f660d66 | 1766 | if (nlk->cb) { |
af65bdfc | 1767 | mutex_unlock(nlk->cb_mutex); |
1da177e4 | 1768 | netlink_destroy_callback(cb); |
6dc878a8 G |
1769 | ret = -EBUSY; |
1770 | goto out; | |
1da177e4 | 1771 | } |
6dc878a8 G |
1772 | /* add reference of module which cb->dump belongs to */ |
1773 | if (!try_module_get(cb->module)) { | |
1774 | mutex_unlock(nlk->cb_mutex); | |
1775 | netlink_destroy_callback(cb); | |
1776 | ret = -EPROTONOSUPPORT; | |
1777 | goto out; | |
1778 | } | |
1779 | ||
1da177e4 | 1780 | nlk->cb = cb; |
af65bdfc | 1781 | mutex_unlock(nlk->cb_mutex); |
1da177e4 | 1782 | |
b44d211e | 1783 | ret = netlink_dump(sk); |
6dc878a8 | 1784 | out: |
1da177e4 | 1785 | sock_put(sk); |
5c58298c | 1786 | |
b44d211e AV |
1787 | if (ret) |
1788 | return ret; | |
1789 | ||
5c58298c DL |
1790 | /* We successfully started a dump, by returning -EINTR we |
1791 | * signal not to send ACK even if it was requested. | |
1792 | */ | |
1793 | return -EINTR; | |
1da177e4 | 1794 | } |
6dc878a8 | 1795 | EXPORT_SYMBOL(__netlink_dump_start); |
1da177e4 LT |
1796 | |
1797 | void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err) | |
1798 | { | |
1799 | struct sk_buff *skb; | |
1800 | struct nlmsghdr *rep; | |
1801 | struct nlmsgerr *errmsg; | |
339bf98f | 1802 | size_t payload = sizeof(*errmsg); |
1da177e4 | 1803 | |
339bf98f TG |
1804 | /* error messages get the original request appened */ |
1805 | if (err) | |
1806 | payload += nlmsg_len(nlh); | |
1da177e4 | 1807 | |
339bf98f | 1808 | skb = nlmsg_new(payload, GFP_KERNEL); |
1da177e4 LT |
1809 | if (!skb) { |
1810 | struct sock *sk; | |
1811 | ||
3b1e0a65 | 1812 | sk = netlink_lookup(sock_net(in_skb->sk), |
b4b51029 | 1813 | in_skb->sk->sk_protocol, |
15e47304 | 1814 | NETLINK_CB(in_skb).portid); |
1da177e4 LT |
1815 | if (sk) { |
1816 | sk->sk_err = ENOBUFS; | |
1817 | sk->sk_error_report(sk); | |
1818 | sock_put(sk); | |
1819 | } | |
1820 | return; | |
1821 | } | |
1822 | ||
15e47304 | 1823 | rep = __nlmsg_put(skb, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, |
5dba93ae | 1824 | NLMSG_ERROR, payload, 0); |
bf8b79e4 | 1825 | errmsg = nlmsg_data(rep); |
1da177e4 | 1826 | errmsg->error = err; |
bf8b79e4 | 1827 | memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(*nlh)); |
15e47304 | 1828 | netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).portid, MSG_DONTWAIT); |
1da177e4 | 1829 | } |
6ac552fd | 1830 | EXPORT_SYMBOL(netlink_ack); |
1da177e4 | 1831 | |
cd40b7d3 | 1832 | int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *, |
1d00a4eb | 1833 | struct nlmsghdr *)) |
82ace47a | 1834 | { |
82ace47a TG |
1835 | struct nlmsghdr *nlh; |
1836 | int err; | |
1837 | ||
1838 | while (skb->len >= nlmsg_total_size(0)) { | |
cd40b7d3 DL |
1839 | int msglen; |
1840 | ||
b529ccf2 | 1841 | nlh = nlmsg_hdr(skb); |
d35b6856 | 1842 | err = 0; |
82ace47a | 1843 | |
ad8e4b75 | 1844 | if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len) |
82ace47a TG |
1845 | return 0; |
1846 | ||
d35b6856 TG |
1847 | /* Only requests are handled by the kernel */ |
1848 | if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) | |
5c58298c | 1849 | goto ack; |
45e7ae7f TG |
1850 | |
1851 | /* Skip control messages */ | |
1852 | if (nlh->nlmsg_type < NLMSG_MIN_TYPE) | |
5c58298c | 1853 | goto ack; |
d35b6856 | 1854 | |
1d00a4eb | 1855 | err = cb(skb, nlh); |
5c58298c DL |
1856 | if (err == -EINTR) |
1857 | goto skip; | |
1858 | ||
1859 | ack: | |
d35b6856 | 1860 | if (nlh->nlmsg_flags & NLM_F_ACK || err) |
82ace47a | 1861 | netlink_ack(skb, nlh, err); |
82ace47a | 1862 | |
5c58298c | 1863 | skip: |
6ac552fd | 1864 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); |
cd40b7d3 DL |
1865 | if (msglen > skb->len) |
1866 | msglen = skb->len; | |
1867 | skb_pull(skb, msglen); | |
82ace47a TG |
1868 | } |
1869 | ||
1870 | return 0; | |
1871 | } | |
6ac552fd | 1872 | EXPORT_SYMBOL(netlink_rcv_skb); |
82ace47a | 1873 | |
d387f6ad TG |
1874 | /** |
1875 | * nlmsg_notify - send a notification netlink message | |
1876 | * @sk: netlink socket to use | |
1877 | * @skb: notification message | |
15e47304 | 1878 | * @portid: destination netlink portid for reports or 0 |
d387f6ad TG |
1879 | * @group: destination multicast group or 0 |
1880 | * @report: 1 to report back, 0 to disable | |
1881 | * @flags: allocation flags | |
1882 | */ | |
15e47304 | 1883 | int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid, |
d387f6ad TG |
1884 | unsigned int group, int report, gfp_t flags) |
1885 | { | |
1886 | int err = 0; | |
1887 | ||
1888 | if (group) { | |
15e47304 | 1889 | int exclude_portid = 0; |
d387f6ad TG |
1890 | |
1891 | if (report) { | |
1892 | atomic_inc(&skb->users); | |
15e47304 | 1893 | exclude_portid = portid; |
d387f6ad TG |
1894 | } |
1895 | ||
1ce85fe4 PNA |
1896 | /* errors reported via destination sk->sk_err, but propagate |
1897 | * delivery errors if NETLINK_BROADCAST_ERROR flag is set */ | |
15e47304 | 1898 | err = nlmsg_multicast(sk, skb, exclude_portid, group, flags); |
d387f6ad TG |
1899 | } |
1900 | ||
1ce85fe4 PNA |
1901 | if (report) { |
1902 | int err2; | |
1903 | ||
15e47304 | 1904 | err2 = nlmsg_unicast(sk, skb, portid); |
1ce85fe4 PNA |
1905 | if (!err || err == -ESRCH) |
1906 | err = err2; | |
1907 | } | |
d387f6ad TG |
1908 | |
1909 | return err; | |
1910 | } | |
6ac552fd | 1911 | EXPORT_SYMBOL(nlmsg_notify); |
d387f6ad | 1912 | |
1da177e4 LT |
1913 | #ifdef CONFIG_PROC_FS |
1914 | struct nl_seq_iter { | |
e372c414 | 1915 | struct seq_net_private p; |
1da177e4 LT |
1916 | int link; |
1917 | int hash_idx; | |
1918 | }; | |
1919 | ||
1920 | static struct sock *netlink_seq_socket_idx(struct seq_file *seq, loff_t pos) | |
1921 | { | |
1922 | struct nl_seq_iter *iter = seq->private; | |
1923 | int i, j; | |
1924 | struct sock *s; | |
1da177e4 LT |
1925 | loff_t off = 0; |
1926 | ||
6ac552fd | 1927 | for (i = 0; i < MAX_LINKS; i++) { |
15e47304 | 1928 | struct nl_portid_hash *hash = &nl_table[i].hash; |
1da177e4 LT |
1929 | |
1930 | for (j = 0; j <= hash->mask; j++) { | |
b67bfe0d | 1931 | sk_for_each(s, &hash->table[j]) { |
1218854a | 1932 | if (sock_net(s) != seq_file_net(seq)) |
b4b51029 | 1933 | continue; |
1da177e4 LT |
1934 | if (off == pos) { |
1935 | iter->link = i; | |
1936 | iter->hash_idx = j; | |
1937 | return s; | |
1938 | } | |
1939 | ++off; | |
1940 | } | |
1941 | } | |
1942 | } | |
1943 | return NULL; | |
1944 | } | |
1945 | ||
1946 | static void *netlink_seq_start(struct seq_file *seq, loff_t *pos) | |
9a429c49 | 1947 | __acquires(nl_table_lock) |
1da177e4 LT |
1948 | { |
1949 | read_lock(&nl_table_lock); | |
1950 | return *pos ? netlink_seq_socket_idx(seq, *pos - 1) : SEQ_START_TOKEN; | |
1951 | } | |
1952 | ||
1953 | static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
1954 | { | |
1955 | struct sock *s; | |
1956 | struct nl_seq_iter *iter; | |
1957 | int i, j; | |
1958 | ||
1959 | ++*pos; | |
1960 | ||
1961 | if (v == SEQ_START_TOKEN) | |
1962 | return netlink_seq_socket_idx(seq, 0); | |
746fac4d | 1963 | |
b4b51029 EB |
1964 | iter = seq->private; |
1965 | s = v; | |
1966 | do { | |
1967 | s = sk_next(s); | |
1218854a | 1968 | } while (s && sock_net(s) != seq_file_net(seq)); |
1da177e4 LT |
1969 | if (s) |
1970 | return s; | |
1971 | ||
1da177e4 LT |
1972 | i = iter->link; |
1973 | j = iter->hash_idx + 1; | |
1974 | ||
1975 | do { | |
15e47304 | 1976 | struct nl_portid_hash *hash = &nl_table[i].hash; |
1da177e4 LT |
1977 | |
1978 | for (; j <= hash->mask; j++) { | |
1979 | s = sk_head(&hash->table[j]); | |
1218854a | 1980 | while (s && sock_net(s) != seq_file_net(seq)) |
b4b51029 | 1981 | s = sk_next(s); |
1da177e4 LT |
1982 | if (s) { |
1983 | iter->link = i; | |
1984 | iter->hash_idx = j; | |
1985 | return s; | |
1986 | } | |
1987 | } | |
1988 | ||
1989 | j = 0; | |
1990 | } while (++i < MAX_LINKS); | |
1991 | ||
1992 | return NULL; | |
1993 | } | |
1994 | ||
1995 | static void netlink_seq_stop(struct seq_file *seq, void *v) | |
9a429c49 | 1996 | __releases(nl_table_lock) |
1da177e4 LT |
1997 | { |
1998 | read_unlock(&nl_table_lock); | |
1999 | } | |
2000 | ||
2001 | ||
2002 | static int netlink_seq_show(struct seq_file *seq, void *v) | |
2003 | { | |
658cb354 | 2004 | if (v == SEQ_START_TOKEN) { |
1da177e4 LT |
2005 | seq_puts(seq, |
2006 | "sk Eth Pid Groups " | |
cf0aa4e0 | 2007 | "Rmem Wmem Dump Locks Drops Inode\n"); |
658cb354 | 2008 | } else { |
1da177e4 LT |
2009 | struct sock *s = v; |
2010 | struct netlink_sock *nlk = nlk_sk(s); | |
2011 | ||
9f1e0ad0 | 2012 | seq_printf(seq, "%pK %-3d %-6u %08x %-8d %-8d %pK %-8d %-8d %-8lu\n", |
1da177e4 LT |
2013 | s, |
2014 | s->sk_protocol, | |
15e47304 | 2015 | nlk->portid, |
513c2500 | 2016 | nlk->groups ? (u32)nlk->groups[0] : 0, |
31e6d363 ED |
2017 | sk_rmem_alloc_get(s), |
2018 | sk_wmem_alloc_get(s), | |
1da177e4 | 2019 | nlk->cb, |
38938bfe | 2020 | atomic_read(&s->sk_refcnt), |
cf0aa4e0 MY |
2021 | atomic_read(&s->sk_drops), |
2022 | sock_i_ino(s) | |
1da177e4 LT |
2023 | ); |
2024 | ||
2025 | } | |
2026 | return 0; | |
2027 | } | |
2028 | ||
56b3d975 | 2029 | static const struct seq_operations netlink_seq_ops = { |
1da177e4 LT |
2030 | .start = netlink_seq_start, |
2031 | .next = netlink_seq_next, | |
2032 | .stop = netlink_seq_stop, | |
2033 | .show = netlink_seq_show, | |
2034 | }; | |
2035 | ||
2036 | ||
2037 | static int netlink_seq_open(struct inode *inode, struct file *file) | |
2038 | { | |
e372c414 DL |
2039 | return seq_open_net(inode, file, &netlink_seq_ops, |
2040 | sizeof(struct nl_seq_iter)); | |
b4b51029 EB |
2041 | } |
2042 | ||
da7071d7 | 2043 | static const struct file_operations netlink_seq_fops = { |
1da177e4 LT |
2044 | .owner = THIS_MODULE, |
2045 | .open = netlink_seq_open, | |
2046 | .read = seq_read, | |
2047 | .llseek = seq_lseek, | |
e372c414 | 2048 | .release = seq_release_net, |
1da177e4 LT |
2049 | }; |
2050 | ||
2051 | #endif | |
2052 | ||
2053 | int netlink_register_notifier(struct notifier_block *nb) | |
2054 | { | |
e041c683 | 2055 | return atomic_notifier_chain_register(&netlink_chain, nb); |
1da177e4 | 2056 | } |
6ac552fd | 2057 | EXPORT_SYMBOL(netlink_register_notifier); |
1da177e4 LT |
2058 | |
2059 | int netlink_unregister_notifier(struct notifier_block *nb) | |
2060 | { | |
e041c683 | 2061 | return atomic_notifier_chain_unregister(&netlink_chain, nb); |
1da177e4 | 2062 | } |
6ac552fd | 2063 | EXPORT_SYMBOL(netlink_unregister_notifier); |
746fac4d | 2064 | |
90ddc4f0 | 2065 | static const struct proto_ops netlink_ops = { |
1da177e4 LT |
2066 | .family = PF_NETLINK, |
2067 | .owner = THIS_MODULE, | |
2068 | .release = netlink_release, | |
2069 | .bind = netlink_bind, | |
2070 | .connect = netlink_connect, | |
2071 | .socketpair = sock_no_socketpair, | |
2072 | .accept = sock_no_accept, | |
2073 | .getname = netlink_getname, | |
2074 | .poll = datagram_poll, | |
2075 | .ioctl = sock_no_ioctl, | |
2076 | .listen = sock_no_listen, | |
2077 | .shutdown = sock_no_shutdown, | |
9a4595bc PM |
2078 | .setsockopt = netlink_setsockopt, |
2079 | .getsockopt = netlink_getsockopt, | |
1da177e4 LT |
2080 | .sendmsg = netlink_sendmsg, |
2081 | .recvmsg = netlink_recvmsg, | |
2082 | .mmap = sock_no_mmap, | |
2083 | .sendpage = sock_no_sendpage, | |
2084 | }; | |
2085 | ||
ec1b4cf7 | 2086 | static const struct net_proto_family netlink_family_ops = { |
1da177e4 LT |
2087 | .family = PF_NETLINK, |
2088 | .create = netlink_create, | |
2089 | .owner = THIS_MODULE, /* for consistency 8) */ | |
2090 | }; | |
2091 | ||
4665079c | 2092 | static int __net_init netlink_net_init(struct net *net) |
b4b51029 EB |
2093 | { |
2094 | #ifdef CONFIG_PROC_FS | |
d4beaa66 | 2095 | if (!proc_create("netlink", 0, net->proc_net, &netlink_seq_fops)) |
b4b51029 EB |
2096 | return -ENOMEM; |
2097 | #endif | |
2098 | return 0; | |
2099 | } | |
2100 | ||
4665079c | 2101 | static void __net_exit netlink_net_exit(struct net *net) |
b4b51029 EB |
2102 | { |
2103 | #ifdef CONFIG_PROC_FS | |
ece31ffd | 2104 | remove_proc_entry("netlink", net->proc_net); |
b4b51029 EB |
2105 | #endif |
2106 | } | |
2107 | ||
b963ea89 DM |
2108 | static void __init netlink_add_usersock_entry(void) |
2109 | { | |
5c398dc8 | 2110 | struct listeners *listeners; |
b963ea89 DM |
2111 | int groups = 32; |
2112 | ||
5c398dc8 | 2113 | listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL); |
b963ea89 | 2114 | if (!listeners) |
5c398dc8 | 2115 | panic("netlink_add_usersock_entry: Cannot allocate listeners\n"); |
b963ea89 DM |
2116 | |
2117 | netlink_table_grab(); | |
2118 | ||
2119 | nl_table[NETLINK_USERSOCK].groups = groups; | |
5c398dc8 | 2120 | rcu_assign_pointer(nl_table[NETLINK_USERSOCK].listeners, listeners); |
b963ea89 DM |
2121 | nl_table[NETLINK_USERSOCK].module = THIS_MODULE; |
2122 | nl_table[NETLINK_USERSOCK].registered = 1; | |
9785e10a | 2123 | nl_table[NETLINK_USERSOCK].flags = NL_CFG_F_NONROOT_SEND; |
b963ea89 DM |
2124 | |
2125 | netlink_table_ungrab(); | |
2126 | } | |
2127 | ||
022cbae6 | 2128 | static struct pernet_operations __net_initdata netlink_net_ops = { |
b4b51029 EB |
2129 | .init = netlink_net_init, |
2130 | .exit = netlink_net_exit, | |
2131 | }; | |
2132 | ||
1da177e4 LT |
2133 | static int __init netlink_proto_init(void) |
2134 | { | |
1da177e4 | 2135 | int i; |
26ff5ddc | 2136 | unsigned long limit; |
1da177e4 LT |
2137 | unsigned int order; |
2138 | int err = proto_register(&netlink_proto, 0); | |
2139 | ||
2140 | if (err != 0) | |
2141 | goto out; | |
2142 | ||
fab25745 | 2143 | BUILD_BUG_ON(sizeof(struct netlink_skb_parms) > FIELD_SIZEOF(struct sk_buff, cb)); |
1da177e4 | 2144 | |
0da974f4 | 2145 | nl_table = kcalloc(MAX_LINKS, sizeof(*nl_table), GFP_KERNEL); |
fab2caf6 AM |
2146 | if (!nl_table) |
2147 | goto panic; | |
1da177e4 | 2148 | |
4481374c JB |
2149 | if (totalram_pages >= (128 * 1024)) |
2150 | limit = totalram_pages >> (21 - PAGE_SHIFT); | |
1da177e4 | 2151 | else |
4481374c | 2152 | limit = totalram_pages >> (23 - PAGE_SHIFT); |
1da177e4 | 2153 | |
26ff5ddc DC |
2154 | order = get_bitmask_order(limit) - 1 + PAGE_SHIFT; |
2155 | limit = (1UL << order) / sizeof(struct hlist_head); | |
2156 | order = get_bitmask_order(min(limit, (unsigned long)UINT_MAX)) - 1; | |
1da177e4 LT |
2157 | |
2158 | for (i = 0; i < MAX_LINKS; i++) { | |
15e47304 | 2159 | struct nl_portid_hash *hash = &nl_table[i].hash; |
1da177e4 | 2160 | |
15e47304 | 2161 | hash->table = nl_portid_hash_zalloc(1 * sizeof(*hash->table)); |
1da177e4 LT |
2162 | if (!hash->table) { |
2163 | while (i-- > 0) | |
15e47304 | 2164 | nl_portid_hash_free(nl_table[i].hash.table, |
1da177e4 LT |
2165 | 1 * sizeof(*hash->table)); |
2166 | kfree(nl_table); | |
fab2caf6 | 2167 | goto panic; |
1da177e4 | 2168 | } |
1da177e4 LT |
2169 | hash->max_shift = order; |
2170 | hash->shift = 0; | |
2171 | hash->mask = 0; | |
2172 | hash->rehash_time = jiffies; | |
2173 | } | |
2174 | ||
b963ea89 DM |
2175 | netlink_add_usersock_entry(); |
2176 | ||
1da177e4 | 2177 | sock_register(&netlink_family_ops); |
b4b51029 | 2178 | register_pernet_subsys(&netlink_net_ops); |
746fac4d | 2179 | /* The netlink device handler may be needed early. */ |
1da177e4 LT |
2180 | rtnetlink_init(); |
2181 | out: | |
2182 | return err; | |
fab2caf6 AM |
2183 | panic: |
2184 | panic("netlink_init: Cannot allocate nl_table\n"); | |
1da177e4 LT |
2185 | } |
2186 | ||
1da177e4 | 2187 | core_initcall(netlink_proto_init); |