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Commit | Line | Data |
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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 | ||
cf0a018a PM |
122 | static void netlink_skb_destructor(struct sk_buff *skb) |
123 | { | |
124 | sock_rfree(skb); | |
125 | } | |
126 | ||
127 | static void netlink_skb_set_owner_r(struct sk_buff *skb, struct sock *sk) | |
128 | { | |
129 | WARN_ON(skb->sk != NULL); | |
130 | skb->sk = sk; | |
131 | skb->destructor = netlink_skb_destructor; | |
132 | atomic_add(skb->truesize, &sk->sk_rmem_alloc); | |
133 | sk_mem_charge(sk, skb->truesize); | |
134 | } | |
135 | ||
1da177e4 LT |
136 | static void netlink_sock_destruct(struct sock *sk) |
137 | { | |
3f660d66 HX |
138 | struct netlink_sock *nlk = nlk_sk(sk); |
139 | ||
3f660d66 HX |
140 | if (nlk->cb) { |
141 | if (nlk->cb->done) | |
142 | nlk->cb->done(nlk->cb); | |
6dc878a8 G |
143 | |
144 | module_put(nlk->cb->module); | |
3f660d66 HX |
145 | netlink_destroy_callback(nlk->cb); |
146 | } | |
147 | ||
1da177e4 LT |
148 | skb_queue_purge(&sk->sk_receive_queue); |
149 | ||
150 | if (!sock_flag(sk, SOCK_DEAD)) { | |
6ac552fd | 151 | printk(KERN_ERR "Freeing alive netlink socket %p\n", sk); |
1da177e4 LT |
152 | return; |
153 | } | |
547b792c IJ |
154 | |
155 | WARN_ON(atomic_read(&sk->sk_rmem_alloc)); | |
156 | WARN_ON(atomic_read(&sk->sk_wmem_alloc)); | |
157 | WARN_ON(nlk_sk(sk)->groups); | |
1da177e4 LT |
158 | } |
159 | ||
6ac552fd PM |
160 | /* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on |
161 | * SMP. Look, when several writers sleep and reader wakes them up, all but one | |
1da177e4 LT |
162 | * immediately hit write lock and grab all the cpus. Exclusive sleep solves |
163 | * this, _but_ remember, it adds useless work on UP machines. | |
164 | */ | |
165 | ||
d136f1bd | 166 | void netlink_table_grab(void) |
9a429c49 | 167 | __acquires(nl_table_lock) |
1da177e4 | 168 | { |
d136f1bd JB |
169 | might_sleep(); |
170 | ||
6abd219c | 171 | write_lock_irq(&nl_table_lock); |
1da177e4 LT |
172 | |
173 | if (atomic_read(&nl_table_users)) { | |
174 | DECLARE_WAITQUEUE(wait, current); | |
175 | ||
176 | add_wait_queue_exclusive(&nl_table_wait, &wait); | |
6ac552fd | 177 | for (;;) { |
1da177e4 LT |
178 | set_current_state(TASK_UNINTERRUPTIBLE); |
179 | if (atomic_read(&nl_table_users) == 0) | |
180 | break; | |
6abd219c | 181 | write_unlock_irq(&nl_table_lock); |
1da177e4 | 182 | schedule(); |
6abd219c | 183 | write_lock_irq(&nl_table_lock); |
1da177e4 LT |
184 | } |
185 | ||
186 | __set_current_state(TASK_RUNNING); | |
187 | remove_wait_queue(&nl_table_wait, &wait); | |
188 | } | |
189 | } | |
190 | ||
d136f1bd | 191 | void netlink_table_ungrab(void) |
9a429c49 | 192 | __releases(nl_table_lock) |
1da177e4 | 193 | { |
6abd219c | 194 | write_unlock_irq(&nl_table_lock); |
1da177e4 LT |
195 | wake_up(&nl_table_wait); |
196 | } | |
197 | ||
6ac552fd | 198 | static inline void |
1da177e4 LT |
199 | netlink_lock_table(void) |
200 | { | |
201 | /* read_lock() synchronizes us to netlink_table_grab */ | |
202 | ||
203 | read_lock(&nl_table_lock); | |
204 | atomic_inc(&nl_table_users); | |
205 | read_unlock(&nl_table_lock); | |
206 | } | |
207 | ||
6ac552fd | 208 | static inline void |
1da177e4 LT |
209 | netlink_unlock_table(void) |
210 | { | |
211 | if (atomic_dec_and_test(&nl_table_users)) | |
212 | wake_up(&nl_table_wait); | |
213 | } | |
214 | ||
15e47304 | 215 | static struct sock *netlink_lookup(struct net *net, int protocol, u32 portid) |
1da177e4 | 216 | { |
15e47304 | 217 | struct nl_portid_hash *hash = &nl_table[protocol].hash; |
1da177e4 LT |
218 | struct hlist_head *head; |
219 | struct sock *sk; | |
1da177e4 LT |
220 | |
221 | read_lock(&nl_table_lock); | |
15e47304 | 222 | head = nl_portid_hashfn(hash, portid); |
b67bfe0d | 223 | sk_for_each(sk, head) { |
15e47304 | 224 | if (net_eq(sock_net(sk), net) && (nlk_sk(sk)->portid == portid)) { |
1da177e4 LT |
225 | sock_hold(sk); |
226 | goto found; | |
227 | } | |
228 | } | |
229 | sk = NULL; | |
230 | found: | |
231 | read_unlock(&nl_table_lock); | |
232 | return sk; | |
233 | } | |
234 | ||
15e47304 | 235 | static struct hlist_head *nl_portid_hash_zalloc(size_t size) |
1da177e4 LT |
236 | { |
237 | if (size <= PAGE_SIZE) | |
ea72912c | 238 | return kzalloc(size, GFP_ATOMIC); |
1da177e4 LT |
239 | else |
240 | return (struct hlist_head *) | |
ea72912c ED |
241 | __get_free_pages(GFP_ATOMIC | __GFP_ZERO, |
242 | get_order(size)); | |
1da177e4 LT |
243 | } |
244 | ||
15e47304 | 245 | static void nl_portid_hash_free(struct hlist_head *table, size_t size) |
1da177e4 LT |
246 | { |
247 | if (size <= PAGE_SIZE) | |
248 | kfree(table); | |
249 | else | |
250 | free_pages((unsigned long)table, get_order(size)); | |
251 | } | |
252 | ||
15e47304 | 253 | static int nl_portid_hash_rehash(struct nl_portid_hash *hash, int grow) |
1da177e4 LT |
254 | { |
255 | unsigned int omask, mask, shift; | |
256 | size_t osize, size; | |
257 | struct hlist_head *otable, *table; | |
258 | int i; | |
259 | ||
260 | omask = mask = hash->mask; | |
261 | osize = size = (mask + 1) * sizeof(*table); | |
262 | shift = hash->shift; | |
263 | ||
264 | if (grow) { | |
265 | if (++shift > hash->max_shift) | |
266 | return 0; | |
267 | mask = mask * 2 + 1; | |
268 | size *= 2; | |
269 | } | |
270 | ||
15e47304 | 271 | table = nl_portid_hash_zalloc(size); |
1da177e4 LT |
272 | if (!table) |
273 | return 0; | |
274 | ||
1da177e4 LT |
275 | otable = hash->table; |
276 | hash->table = table; | |
277 | hash->mask = mask; | |
278 | hash->shift = shift; | |
279 | get_random_bytes(&hash->rnd, sizeof(hash->rnd)); | |
280 | ||
281 | for (i = 0; i <= omask; i++) { | |
282 | struct sock *sk; | |
b67bfe0d | 283 | struct hlist_node *tmp; |
1da177e4 | 284 | |
b67bfe0d | 285 | sk_for_each_safe(sk, tmp, &otable[i]) |
15e47304 | 286 | __sk_add_node(sk, nl_portid_hashfn(hash, nlk_sk(sk)->portid)); |
1da177e4 LT |
287 | } |
288 | ||
15e47304 | 289 | nl_portid_hash_free(otable, osize); |
1da177e4 LT |
290 | hash->rehash_time = jiffies + 10 * 60 * HZ; |
291 | return 1; | |
292 | } | |
293 | ||
15e47304 | 294 | static inline int nl_portid_hash_dilute(struct nl_portid_hash *hash, int len) |
1da177e4 LT |
295 | { |
296 | int avg = hash->entries >> hash->shift; | |
297 | ||
15e47304 | 298 | if (unlikely(avg > 1) && nl_portid_hash_rehash(hash, 1)) |
1da177e4 LT |
299 | return 1; |
300 | ||
301 | if (unlikely(len > avg) && time_after(jiffies, hash->rehash_time)) { | |
15e47304 | 302 | nl_portid_hash_rehash(hash, 0); |
1da177e4 LT |
303 | return 1; |
304 | } | |
305 | ||
306 | return 0; | |
307 | } | |
308 | ||
90ddc4f0 | 309 | static const struct proto_ops netlink_ops; |
1da177e4 | 310 | |
4277a083 PM |
311 | static void |
312 | netlink_update_listeners(struct sock *sk) | |
313 | { | |
314 | struct netlink_table *tbl = &nl_table[sk->sk_protocol]; | |
4277a083 PM |
315 | unsigned long mask; |
316 | unsigned int i; | |
6d772ac5 ED |
317 | struct listeners *listeners; |
318 | ||
319 | listeners = nl_deref_protected(tbl->listeners); | |
320 | if (!listeners) | |
321 | return; | |
4277a083 | 322 | |
b4ff4f04 | 323 | for (i = 0; i < NLGRPLONGS(tbl->groups); i++) { |
4277a083 | 324 | mask = 0; |
b67bfe0d | 325 | sk_for_each_bound(sk, &tbl->mc_list) { |
b4ff4f04 JB |
326 | if (i < NLGRPLONGS(nlk_sk(sk)->ngroups)) |
327 | mask |= nlk_sk(sk)->groups[i]; | |
328 | } | |
6d772ac5 | 329 | listeners->masks[i] = mask; |
4277a083 PM |
330 | } |
331 | /* this function is only called with the netlink table "grabbed", which | |
332 | * makes sure updates are visible before bind or setsockopt return. */ | |
333 | } | |
334 | ||
15e47304 | 335 | static int netlink_insert(struct sock *sk, struct net *net, u32 portid) |
1da177e4 | 336 | { |
15e47304 | 337 | struct nl_portid_hash *hash = &nl_table[sk->sk_protocol].hash; |
1da177e4 LT |
338 | struct hlist_head *head; |
339 | int err = -EADDRINUSE; | |
340 | struct sock *osk; | |
1da177e4 LT |
341 | int len; |
342 | ||
343 | netlink_table_grab(); | |
15e47304 | 344 | head = nl_portid_hashfn(hash, portid); |
1da177e4 | 345 | len = 0; |
b67bfe0d | 346 | sk_for_each(osk, head) { |
15e47304 | 347 | if (net_eq(sock_net(osk), net) && (nlk_sk(osk)->portid == portid)) |
1da177e4 LT |
348 | break; |
349 | len++; | |
350 | } | |
b67bfe0d | 351 | if (osk) |
1da177e4 LT |
352 | goto err; |
353 | ||
354 | err = -EBUSY; | |
15e47304 | 355 | if (nlk_sk(sk)->portid) |
1da177e4 LT |
356 | goto err; |
357 | ||
358 | err = -ENOMEM; | |
359 | if (BITS_PER_LONG > 32 && unlikely(hash->entries >= UINT_MAX)) | |
360 | goto err; | |
361 | ||
15e47304 EB |
362 | if (len && nl_portid_hash_dilute(hash, len)) |
363 | head = nl_portid_hashfn(hash, portid); | |
1da177e4 | 364 | hash->entries++; |
15e47304 | 365 | nlk_sk(sk)->portid = portid; |
1da177e4 LT |
366 | sk_add_node(sk, head); |
367 | err = 0; | |
368 | ||
369 | err: | |
370 | netlink_table_ungrab(); | |
371 | return err; | |
372 | } | |
373 | ||
374 | static void netlink_remove(struct sock *sk) | |
375 | { | |
376 | netlink_table_grab(); | |
d470e3b4 DM |
377 | if (sk_del_node_init(sk)) |
378 | nl_table[sk->sk_protocol].hash.entries--; | |
f7fa9b10 | 379 | if (nlk_sk(sk)->subscriptions) |
1da177e4 LT |
380 | __sk_del_bind_node(sk); |
381 | netlink_table_ungrab(); | |
382 | } | |
383 | ||
384 | static struct proto netlink_proto = { | |
385 | .name = "NETLINK", | |
386 | .owner = THIS_MODULE, | |
387 | .obj_size = sizeof(struct netlink_sock), | |
388 | }; | |
389 | ||
1b8d7ae4 EB |
390 | static int __netlink_create(struct net *net, struct socket *sock, |
391 | struct mutex *cb_mutex, int protocol) | |
1da177e4 LT |
392 | { |
393 | struct sock *sk; | |
394 | struct netlink_sock *nlk; | |
ab33a171 PM |
395 | |
396 | sock->ops = &netlink_ops; | |
397 | ||
6257ff21 | 398 | sk = sk_alloc(net, PF_NETLINK, GFP_KERNEL, &netlink_proto); |
ab33a171 PM |
399 | if (!sk) |
400 | return -ENOMEM; | |
401 | ||
402 | sock_init_data(sock, sk); | |
403 | ||
404 | nlk = nlk_sk(sk); | |
658cb354 | 405 | if (cb_mutex) { |
ffa4d721 | 406 | nlk->cb_mutex = cb_mutex; |
658cb354 | 407 | } else { |
ffa4d721 PM |
408 | nlk->cb_mutex = &nlk->cb_def_mutex; |
409 | mutex_init(nlk->cb_mutex); | |
410 | } | |
ab33a171 PM |
411 | init_waitqueue_head(&nlk->wait); |
412 | ||
413 | sk->sk_destruct = netlink_sock_destruct; | |
414 | sk->sk_protocol = protocol; | |
415 | return 0; | |
416 | } | |
417 | ||
3f378b68 EP |
418 | static int netlink_create(struct net *net, struct socket *sock, int protocol, |
419 | int kern) | |
ab33a171 PM |
420 | { |
421 | struct module *module = NULL; | |
af65bdfc | 422 | struct mutex *cb_mutex; |
f7fa9b10 | 423 | struct netlink_sock *nlk; |
03292745 | 424 | void (*bind)(int group); |
ab33a171 | 425 | int err = 0; |
1da177e4 LT |
426 | |
427 | sock->state = SS_UNCONNECTED; | |
428 | ||
429 | if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM) | |
430 | return -ESOCKTNOSUPPORT; | |
431 | ||
6ac552fd | 432 | if (protocol < 0 || protocol >= MAX_LINKS) |
1da177e4 LT |
433 | return -EPROTONOSUPPORT; |
434 | ||
77247bbb | 435 | netlink_lock_table(); |
95a5afca | 436 | #ifdef CONFIG_MODULES |
ab33a171 | 437 | if (!nl_table[protocol].registered) { |
77247bbb | 438 | netlink_unlock_table(); |
4fdb3bb7 | 439 | request_module("net-pf-%d-proto-%d", PF_NETLINK, protocol); |
77247bbb | 440 | netlink_lock_table(); |
4fdb3bb7 | 441 | } |
ab33a171 PM |
442 | #endif |
443 | if (nl_table[protocol].registered && | |
444 | try_module_get(nl_table[protocol].module)) | |
445 | module = nl_table[protocol].module; | |
974c37e9 AD |
446 | else |
447 | err = -EPROTONOSUPPORT; | |
af65bdfc | 448 | cb_mutex = nl_table[protocol].cb_mutex; |
03292745 | 449 | bind = nl_table[protocol].bind; |
77247bbb | 450 | netlink_unlock_table(); |
4fdb3bb7 | 451 | |
974c37e9 AD |
452 | if (err < 0) |
453 | goto out; | |
454 | ||
6ac552fd PM |
455 | err = __netlink_create(net, sock, cb_mutex, protocol); |
456 | if (err < 0) | |
f7fa9b10 PM |
457 | goto out_module; |
458 | ||
6f756a8c | 459 | local_bh_disable(); |
c1fd3b94 | 460 | sock_prot_inuse_add(net, &netlink_proto, 1); |
6f756a8c DM |
461 | local_bh_enable(); |
462 | ||
f7fa9b10 | 463 | nlk = nlk_sk(sock->sk); |
f7fa9b10 | 464 | nlk->module = module; |
03292745 | 465 | nlk->netlink_bind = bind; |
ab33a171 PM |
466 | out: |
467 | return err; | |
1da177e4 | 468 | |
ab33a171 PM |
469 | out_module: |
470 | module_put(module); | |
471 | goto out; | |
1da177e4 LT |
472 | } |
473 | ||
474 | static int netlink_release(struct socket *sock) | |
475 | { | |
476 | struct sock *sk = sock->sk; | |
477 | struct netlink_sock *nlk; | |
478 | ||
479 | if (!sk) | |
480 | return 0; | |
481 | ||
482 | netlink_remove(sk); | |
ac57b3a9 | 483 | sock_orphan(sk); |
1da177e4 LT |
484 | nlk = nlk_sk(sk); |
485 | ||
3f660d66 HX |
486 | /* |
487 | * OK. Socket is unlinked, any packets that arrive now | |
488 | * will be purged. | |
489 | */ | |
1da177e4 | 490 | |
1da177e4 LT |
491 | sock->sk = NULL; |
492 | wake_up_interruptible_all(&nlk->wait); | |
493 | ||
494 | skb_queue_purge(&sk->sk_write_queue); | |
495 | ||
15e47304 | 496 | if (nlk->portid) { |
1da177e4 | 497 | struct netlink_notify n = { |
3b1e0a65 | 498 | .net = sock_net(sk), |
1da177e4 | 499 | .protocol = sk->sk_protocol, |
15e47304 | 500 | .portid = nlk->portid, |
1da177e4 | 501 | }; |
e041c683 AS |
502 | atomic_notifier_call_chain(&netlink_chain, |
503 | NETLINK_URELEASE, &n); | |
746fac4d | 504 | } |
4fdb3bb7 | 505 | |
5e7c001c | 506 | module_put(nlk->module); |
4fdb3bb7 | 507 | |
4277a083 | 508 | netlink_table_grab(); |
aed81560 | 509 | if (netlink_is_kernel(sk)) { |
869e58f8 DL |
510 | BUG_ON(nl_table[sk->sk_protocol].registered == 0); |
511 | if (--nl_table[sk->sk_protocol].registered == 0) { | |
6d772ac5 ED |
512 | struct listeners *old; |
513 | ||
514 | old = nl_deref_protected(nl_table[sk->sk_protocol].listeners); | |
515 | RCU_INIT_POINTER(nl_table[sk->sk_protocol].listeners, NULL); | |
516 | kfree_rcu(old, rcu); | |
869e58f8 | 517 | nl_table[sk->sk_protocol].module = NULL; |
9785e10a PNA |
518 | nl_table[sk->sk_protocol].bind = NULL; |
519 | nl_table[sk->sk_protocol].flags = 0; | |
869e58f8 DL |
520 | nl_table[sk->sk_protocol].registered = 0; |
521 | } | |
658cb354 | 522 | } else if (nlk->subscriptions) { |
4277a083 | 523 | netlink_update_listeners(sk); |
658cb354 | 524 | } |
4277a083 | 525 | netlink_table_ungrab(); |
77247bbb | 526 | |
f7fa9b10 PM |
527 | kfree(nlk->groups); |
528 | nlk->groups = NULL; | |
529 | ||
3755810c | 530 | local_bh_disable(); |
c1fd3b94 | 531 | sock_prot_inuse_add(sock_net(sk), &netlink_proto, -1); |
3755810c | 532 | local_bh_enable(); |
1da177e4 LT |
533 | sock_put(sk); |
534 | return 0; | |
535 | } | |
536 | ||
537 | static int netlink_autobind(struct socket *sock) | |
538 | { | |
539 | struct sock *sk = sock->sk; | |
3b1e0a65 | 540 | struct net *net = sock_net(sk); |
15e47304 | 541 | struct nl_portid_hash *hash = &nl_table[sk->sk_protocol].hash; |
1da177e4 LT |
542 | struct hlist_head *head; |
543 | struct sock *osk; | |
15e47304 | 544 | s32 portid = task_tgid_vnr(current); |
1da177e4 LT |
545 | int err; |
546 | static s32 rover = -4097; | |
547 | ||
548 | retry: | |
549 | cond_resched(); | |
550 | netlink_table_grab(); | |
15e47304 | 551 | head = nl_portid_hashfn(hash, portid); |
b67bfe0d | 552 | sk_for_each(osk, head) { |
878628fb | 553 | if (!net_eq(sock_net(osk), net)) |
b4b51029 | 554 | continue; |
15e47304 EB |
555 | if (nlk_sk(osk)->portid == portid) { |
556 | /* Bind collision, search negative portid values. */ | |
557 | portid = rover--; | |
1da177e4 LT |
558 | if (rover > -4097) |
559 | rover = -4097; | |
560 | netlink_table_ungrab(); | |
561 | goto retry; | |
562 | } | |
563 | } | |
564 | netlink_table_ungrab(); | |
565 | ||
15e47304 | 566 | err = netlink_insert(sk, net, portid); |
1da177e4 LT |
567 | if (err == -EADDRINUSE) |
568 | goto retry; | |
d470e3b4 DM |
569 | |
570 | /* If 2 threads race to autobind, that is fine. */ | |
571 | if (err == -EBUSY) | |
572 | err = 0; | |
573 | ||
574 | return err; | |
1da177e4 LT |
575 | } |
576 | ||
b57ef81f | 577 | static inline int netlink_capable(const struct socket *sock, unsigned int flag) |
746fac4d | 578 | { |
9785e10a | 579 | return (nl_table[sock->sk->sk_protocol].flags & flag) || |
df008c91 | 580 | ns_capable(sock_net(sock->sk)->user_ns, CAP_NET_ADMIN); |
746fac4d | 581 | } |
1da177e4 | 582 | |
f7fa9b10 PM |
583 | static void |
584 | netlink_update_subscriptions(struct sock *sk, unsigned int subscriptions) | |
585 | { | |
586 | struct netlink_sock *nlk = nlk_sk(sk); | |
587 | ||
588 | if (nlk->subscriptions && !subscriptions) | |
589 | __sk_del_bind_node(sk); | |
590 | else if (!nlk->subscriptions && subscriptions) | |
591 | sk_add_bind_node(sk, &nl_table[sk->sk_protocol].mc_list); | |
592 | nlk->subscriptions = subscriptions; | |
593 | } | |
594 | ||
b4ff4f04 | 595 | static int netlink_realloc_groups(struct sock *sk) |
513c2500 PM |
596 | { |
597 | struct netlink_sock *nlk = nlk_sk(sk); | |
598 | unsigned int groups; | |
b4ff4f04 | 599 | unsigned long *new_groups; |
513c2500 PM |
600 | int err = 0; |
601 | ||
b4ff4f04 JB |
602 | netlink_table_grab(); |
603 | ||
513c2500 | 604 | groups = nl_table[sk->sk_protocol].groups; |
b4ff4f04 | 605 | if (!nl_table[sk->sk_protocol].registered) { |
513c2500 | 606 | err = -ENOENT; |
b4ff4f04 JB |
607 | goto out_unlock; |
608 | } | |
513c2500 | 609 | |
b4ff4f04 JB |
610 | if (nlk->ngroups >= groups) |
611 | goto out_unlock; | |
513c2500 | 612 | |
b4ff4f04 JB |
613 | new_groups = krealloc(nlk->groups, NLGRPSZ(groups), GFP_ATOMIC); |
614 | if (new_groups == NULL) { | |
615 | err = -ENOMEM; | |
616 | goto out_unlock; | |
617 | } | |
6ac552fd | 618 | memset((char *)new_groups + NLGRPSZ(nlk->ngroups), 0, |
b4ff4f04 JB |
619 | NLGRPSZ(groups) - NLGRPSZ(nlk->ngroups)); |
620 | ||
621 | nlk->groups = new_groups; | |
513c2500 | 622 | nlk->ngroups = groups; |
b4ff4f04 JB |
623 | out_unlock: |
624 | netlink_table_ungrab(); | |
625 | return err; | |
513c2500 PM |
626 | } |
627 | ||
6ac552fd PM |
628 | static int netlink_bind(struct socket *sock, struct sockaddr *addr, |
629 | int addr_len) | |
1da177e4 LT |
630 | { |
631 | struct sock *sk = sock->sk; | |
3b1e0a65 | 632 | struct net *net = sock_net(sk); |
1da177e4 LT |
633 | struct netlink_sock *nlk = nlk_sk(sk); |
634 | struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr; | |
635 | int err; | |
746fac4d | 636 | |
4e4b5376 HFS |
637 | if (addr_len < sizeof(struct sockaddr_nl)) |
638 | return -EINVAL; | |
639 | ||
1da177e4 LT |
640 | if (nladdr->nl_family != AF_NETLINK) |
641 | return -EINVAL; | |
642 | ||
643 | /* Only superuser is allowed to listen multicasts */ | |
513c2500 | 644 | if (nladdr->nl_groups) { |
9785e10a | 645 | if (!netlink_capable(sock, NL_CFG_F_NONROOT_RECV)) |
513c2500 | 646 | return -EPERM; |
b4ff4f04 JB |
647 | err = netlink_realloc_groups(sk); |
648 | if (err) | |
649 | return err; | |
513c2500 | 650 | } |
1da177e4 | 651 | |
15e47304 EB |
652 | if (nlk->portid) { |
653 | if (nladdr->nl_pid != nlk->portid) | |
1da177e4 LT |
654 | return -EINVAL; |
655 | } else { | |
656 | err = nladdr->nl_pid ? | |
b4b51029 | 657 | netlink_insert(sk, net, nladdr->nl_pid) : |
1da177e4 LT |
658 | netlink_autobind(sock); |
659 | if (err) | |
660 | return err; | |
661 | } | |
662 | ||
513c2500 | 663 | if (!nladdr->nl_groups && (nlk->groups == NULL || !(u32)nlk->groups[0])) |
1da177e4 LT |
664 | return 0; |
665 | ||
666 | netlink_table_grab(); | |
f7fa9b10 | 667 | netlink_update_subscriptions(sk, nlk->subscriptions + |
746fac4d YH |
668 | hweight32(nladdr->nl_groups) - |
669 | hweight32(nlk->groups[0])); | |
670 | nlk->groups[0] = (nlk->groups[0] & ~0xffffffffUL) | nladdr->nl_groups; | |
4277a083 | 671 | netlink_update_listeners(sk); |
1da177e4 LT |
672 | netlink_table_ungrab(); |
673 | ||
03292745 PNA |
674 | if (nlk->netlink_bind && nlk->groups[0]) { |
675 | int i; | |
676 | ||
677 | for (i=0; i<nlk->ngroups; i++) { | |
678 | if (test_bit(i, nlk->groups)) | |
679 | nlk->netlink_bind(i); | |
680 | } | |
681 | } | |
682 | ||
1da177e4 LT |
683 | return 0; |
684 | } | |
685 | ||
686 | static int netlink_connect(struct socket *sock, struct sockaddr *addr, | |
687 | int alen, int flags) | |
688 | { | |
689 | int err = 0; | |
690 | struct sock *sk = sock->sk; | |
691 | struct netlink_sock *nlk = nlk_sk(sk); | |
6ac552fd | 692 | struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr; |
1da177e4 | 693 | |
6503d961 CG |
694 | if (alen < sizeof(addr->sa_family)) |
695 | return -EINVAL; | |
696 | ||
1da177e4 LT |
697 | if (addr->sa_family == AF_UNSPEC) { |
698 | sk->sk_state = NETLINK_UNCONNECTED; | |
15e47304 | 699 | nlk->dst_portid = 0; |
d629b836 | 700 | nlk->dst_group = 0; |
1da177e4 LT |
701 | return 0; |
702 | } | |
703 | if (addr->sa_family != AF_NETLINK) | |
704 | return -EINVAL; | |
705 | ||
706 | /* Only superuser is allowed to send multicasts */ | |
9785e10a | 707 | if (nladdr->nl_groups && !netlink_capable(sock, NL_CFG_F_NONROOT_SEND)) |
1da177e4 LT |
708 | return -EPERM; |
709 | ||
15e47304 | 710 | if (!nlk->portid) |
1da177e4 LT |
711 | err = netlink_autobind(sock); |
712 | ||
713 | if (err == 0) { | |
714 | sk->sk_state = NETLINK_CONNECTED; | |
15e47304 | 715 | nlk->dst_portid = nladdr->nl_pid; |
d629b836 | 716 | nlk->dst_group = ffs(nladdr->nl_groups); |
1da177e4 LT |
717 | } |
718 | ||
719 | return err; | |
720 | } | |
721 | ||
6ac552fd PM |
722 | static int netlink_getname(struct socket *sock, struct sockaddr *addr, |
723 | int *addr_len, int peer) | |
1da177e4 LT |
724 | { |
725 | struct sock *sk = sock->sk; | |
726 | struct netlink_sock *nlk = nlk_sk(sk); | |
13cfa97b | 727 | DECLARE_SOCKADDR(struct sockaddr_nl *, nladdr, addr); |
746fac4d | 728 | |
1da177e4 LT |
729 | nladdr->nl_family = AF_NETLINK; |
730 | nladdr->nl_pad = 0; | |
731 | *addr_len = sizeof(*nladdr); | |
732 | ||
733 | if (peer) { | |
15e47304 | 734 | nladdr->nl_pid = nlk->dst_portid; |
d629b836 | 735 | nladdr->nl_groups = netlink_group_mask(nlk->dst_group); |
1da177e4 | 736 | } else { |
15e47304 | 737 | nladdr->nl_pid = nlk->portid; |
513c2500 | 738 | nladdr->nl_groups = nlk->groups ? nlk->groups[0] : 0; |
1da177e4 LT |
739 | } |
740 | return 0; | |
741 | } | |
742 | ||
743 | static void netlink_overrun(struct sock *sk) | |
744 | { | |
38938bfe PNA |
745 | struct netlink_sock *nlk = nlk_sk(sk); |
746 | ||
747 | if (!(nlk->flags & NETLINK_RECV_NO_ENOBUFS)) { | |
cd967e05 | 748 | if (!test_and_set_bit(NETLINK_CONGESTED, &nlk_sk(sk)->state)) { |
38938bfe PNA |
749 | sk->sk_err = ENOBUFS; |
750 | sk->sk_error_report(sk); | |
751 | } | |
1da177e4 | 752 | } |
38938bfe | 753 | atomic_inc(&sk->sk_drops); |
1da177e4 LT |
754 | } |
755 | ||
15e47304 | 756 | static struct sock *netlink_getsockbyportid(struct sock *ssk, u32 portid) |
1da177e4 | 757 | { |
1da177e4 LT |
758 | struct sock *sock; |
759 | struct netlink_sock *nlk; | |
760 | ||
15e47304 | 761 | sock = netlink_lookup(sock_net(ssk), ssk->sk_protocol, portid); |
1da177e4 LT |
762 | if (!sock) |
763 | return ERR_PTR(-ECONNREFUSED); | |
764 | ||
765 | /* Don't bother queuing skb if kernel socket has no input function */ | |
766 | nlk = nlk_sk(sock); | |
cd40b7d3 | 767 | if (sock->sk_state == NETLINK_CONNECTED && |
15e47304 | 768 | nlk->dst_portid != nlk_sk(ssk)->portid) { |
1da177e4 LT |
769 | sock_put(sock); |
770 | return ERR_PTR(-ECONNREFUSED); | |
771 | } | |
772 | return sock; | |
773 | } | |
774 | ||
775 | struct sock *netlink_getsockbyfilp(struct file *filp) | |
776 | { | |
496ad9aa | 777 | struct inode *inode = file_inode(filp); |
1da177e4 LT |
778 | struct sock *sock; |
779 | ||
780 | if (!S_ISSOCK(inode->i_mode)) | |
781 | return ERR_PTR(-ENOTSOCK); | |
782 | ||
783 | sock = SOCKET_I(inode)->sk; | |
784 | if (sock->sk_family != AF_NETLINK) | |
785 | return ERR_PTR(-EINVAL); | |
786 | ||
787 | sock_hold(sock); | |
788 | return sock; | |
789 | } | |
790 | ||
791 | /* | |
792 | * Attach a skb to a netlink socket. | |
793 | * The caller must hold a reference to the destination socket. On error, the | |
794 | * reference is dropped. The skb is not send to the destination, just all | |
795 | * all error checks are performed and memory in the queue is reserved. | |
796 | * Return values: | |
797 | * < 0: error. skb freed, reference to sock dropped. | |
798 | * 0: continue | |
799 | * 1: repeat lookup - reference dropped while waiting for socket memory. | |
800 | */ | |
9457afee | 801 | int netlink_attachskb(struct sock *sk, struct sk_buff *skb, |
c3d8d1e3 | 802 | long *timeo, struct sock *ssk) |
1da177e4 LT |
803 | { |
804 | struct netlink_sock *nlk; | |
805 | ||
806 | nlk = nlk_sk(sk); | |
807 | ||
808 | if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || | |
cd967e05 | 809 | test_bit(NETLINK_CONGESTED, &nlk->state)) { |
1da177e4 | 810 | DECLARE_WAITQUEUE(wait, current); |
c3d8d1e3 | 811 | if (!*timeo) { |
aed81560 | 812 | if (!ssk || netlink_is_kernel(ssk)) |
1da177e4 LT |
813 | netlink_overrun(sk); |
814 | sock_put(sk); | |
815 | kfree_skb(skb); | |
816 | return -EAGAIN; | |
817 | } | |
818 | ||
819 | __set_current_state(TASK_INTERRUPTIBLE); | |
820 | add_wait_queue(&nlk->wait, &wait); | |
821 | ||
822 | if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || | |
cd967e05 | 823 | test_bit(NETLINK_CONGESTED, &nlk->state)) && |
1da177e4 | 824 | !sock_flag(sk, SOCK_DEAD)) |
c3d8d1e3 | 825 | *timeo = schedule_timeout(*timeo); |
1da177e4 LT |
826 | |
827 | __set_current_state(TASK_RUNNING); | |
828 | remove_wait_queue(&nlk->wait, &wait); | |
829 | sock_put(sk); | |
830 | ||
831 | if (signal_pending(current)) { | |
832 | kfree_skb(skb); | |
c3d8d1e3 | 833 | return sock_intr_errno(*timeo); |
1da177e4 LT |
834 | } |
835 | return 1; | |
836 | } | |
cf0a018a | 837 | netlink_skb_set_owner_r(skb, sk); |
1da177e4 LT |
838 | return 0; |
839 | } | |
840 | ||
4a7e7c2a | 841 | static int __netlink_sendskb(struct sock *sk, struct sk_buff *skb) |
1da177e4 | 842 | { |
1da177e4 LT |
843 | int len = skb->len; |
844 | ||
1da177e4 LT |
845 | skb_queue_tail(&sk->sk_receive_queue, skb); |
846 | sk->sk_data_ready(sk, len); | |
4a7e7c2a ED |
847 | return len; |
848 | } | |
849 | ||
850 | int netlink_sendskb(struct sock *sk, struct sk_buff *skb) | |
851 | { | |
852 | int len = __netlink_sendskb(sk, skb); | |
853 | ||
1da177e4 LT |
854 | sock_put(sk); |
855 | return len; | |
856 | } | |
857 | ||
858 | void netlink_detachskb(struct sock *sk, struct sk_buff *skb) | |
859 | { | |
860 | kfree_skb(skb); | |
861 | sock_put(sk); | |
862 | } | |
863 | ||
b57ef81f | 864 | static struct sk_buff *netlink_trim(struct sk_buff *skb, gfp_t allocation) |
1da177e4 LT |
865 | { |
866 | int delta; | |
867 | ||
1298ca46 | 868 | WARN_ON(skb->sk != NULL); |
1da177e4 | 869 | |
4305b541 | 870 | delta = skb->end - skb->tail; |
1da177e4 LT |
871 | if (delta * 2 < skb->truesize) |
872 | return skb; | |
873 | ||
874 | if (skb_shared(skb)) { | |
875 | struct sk_buff *nskb = skb_clone(skb, allocation); | |
876 | if (!nskb) | |
877 | return skb; | |
8460c00f | 878 | consume_skb(skb); |
1da177e4 LT |
879 | skb = nskb; |
880 | } | |
881 | ||
882 | if (!pskb_expand_head(skb, 0, -delta, allocation)) | |
883 | skb->truesize -= delta; | |
884 | ||
885 | return skb; | |
886 | } | |
887 | ||
b57ef81f | 888 | static void netlink_rcv_wake(struct sock *sk) |
cd40b7d3 DL |
889 | { |
890 | struct netlink_sock *nlk = nlk_sk(sk); | |
891 | ||
892 | if (skb_queue_empty(&sk->sk_receive_queue)) | |
cd967e05 PM |
893 | clear_bit(NETLINK_CONGESTED, &nlk->state); |
894 | if (!test_bit(NETLINK_CONGESTED, &nlk->state)) | |
cd40b7d3 DL |
895 | wake_up_interruptible(&nlk->wait); |
896 | } | |
897 | ||
3fbc2905 EB |
898 | static int netlink_unicast_kernel(struct sock *sk, struct sk_buff *skb, |
899 | struct sock *ssk) | |
cd40b7d3 DL |
900 | { |
901 | int ret; | |
902 | struct netlink_sock *nlk = nlk_sk(sk); | |
903 | ||
904 | ret = -ECONNREFUSED; | |
905 | if (nlk->netlink_rcv != NULL) { | |
906 | ret = skb->len; | |
cf0a018a | 907 | netlink_skb_set_owner_r(skb, sk); |
e32123e5 | 908 | NETLINK_CB(skb).sk = ssk; |
cd40b7d3 | 909 | nlk->netlink_rcv(skb); |
bfb253c9 ED |
910 | consume_skb(skb); |
911 | } else { | |
912 | kfree_skb(skb); | |
cd40b7d3 | 913 | } |
cd40b7d3 DL |
914 | sock_put(sk); |
915 | return ret; | |
916 | } | |
917 | ||
918 | int netlink_unicast(struct sock *ssk, struct sk_buff *skb, | |
15e47304 | 919 | u32 portid, int nonblock) |
1da177e4 LT |
920 | { |
921 | struct sock *sk; | |
922 | int err; | |
923 | long timeo; | |
924 | ||
925 | skb = netlink_trim(skb, gfp_any()); | |
926 | ||
927 | timeo = sock_sndtimeo(ssk, nonblock); | |
928 | retry: | |
15e47304 | 929 | sk = netlink_getsockbyportid(ssk, portid); |
1da177e4 LT |
930 | if (IS_ERR(sk)) { |
931 | kfree_skb(skb); | |
932 | return PTR_ERR(sk); | |
933 | } | |
cd40b7d3 | 934 | if (netlink_is_kernel(sk)) |
3fbc2905 | 935 | return netlink_unicast_kernel(sk, skb, ssk); |
cd40b7d3 | 936 | |
b1153f29 | 937 | if (sk_filter(sk, skb)) { |
84874607 | 938 | err = skb->len; |
b1153f29 SH |
939 | kfree_skb(skb); |
940 | sock_put(sk); | |
941 | return err; | |
942 | } | |
943 | ||
9457afee | 944 | err = netlink_attachskb(sk, skb, &timeo, ssk); |
1da177e4 LT |
945 | if (err == 1) |
946 | goto retry; | |
947 | if (err) | |
948 | return err; | |
949 | ||
7ee015e0 | 950 | return netlink_sendskb(sk, skb); |
1da177e4 | 951 | } |
6ac552fd | 952 | EXPORT_SYMBOL(netlink_unicast); |
1da177e4 | 953 | |
4277a083 PM |
954 | int netlink_has_listeners(struct sock *sk, unsigned int group) |
955 | { | |
956 | int res = 0; | |
5c398dc8 | 957 | struct listeners *listeners; |
4277a083 | 958 | |
aed81560 | 959 | BUG_ON(!netlink_is_kernel(sk)); |
b4ff4f04 JB |
960 | |
961 | rcu_read_lock(); | |
962 | listeners = rcu_dereference(nl_table[sk->sk_protocol].listeners); | |
963 | ||
6d772ac5 | 964 | if (listeners && group - 1 < nl_table[sk->sk_protocol].groups) |
5c398dc8 | 965 | res = test_bit(group - 1, listeners->masks); |
b4ff4f04 JB |
966 | |
967 | rcu_read_unlock(); | |
968 | ||
4277a083 PM |
969 | return res; |
970 | } | |
971 | EXPORT_SYMBOL_GPL(netlink_has_listeners); | |
972 | ||
b57ef81f | 973 | static int netlink_broadcast_deliver(struct sock *sk, struct sk_buff *skb) |
1da177e4 LT |
974 | { |
975 | struct netlink_sock *nlk = nlk_sk(sk); | |
976 | ||
977 | if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf && | |
cd967e05 | 978 | !test_bit(NETLINK_CONGESTED, &nlk->state)) { |
cf0a018a | 979 | netlink_skb_set_owner_r(skb, sk); |
4a7e7c2a | 980 | __netlink_sendskb(sk, skb); |
2c645800 | 981 | return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1); |
1da177e4 LT |
982 | } |
983 | return -1; | |
984 | } | |
985 | ||
986 | struct netlink_broadcast_data { | |
987 | struct sock *exclude_sk; | |
b4b51029 | 988 | struct net *net; |
15e47304 | 989 | u32 portid; |
1da177e4 LT |
990 | u32 group; |
991 | int failure; | |
ff491a73 | 992 | int delivery_failure; |
1da177e4 LT |
993 | int congested; |
994 | int delivered; | |
7d877f3b | 995 | gfp_t allocation; |
1da177e4 | 996 | struct sk_buff *skb, *skb2; |
910a7e90 EB |
997 | int (*tx_filter)(struct sock *dsk, struct sk_buff *skb, void *data); |
998 | void *tx_data; | |
1da177e4 LT |
999 | }; |
1000 | ||
b57ef81f | 1001 | static int do_one_broadcast(struct sock *sk, |
1da177e4 LT |
1002 | struct netlink_broadcast_data *p) |
1003 | { | |
1004 | struct netlink_sock *nlk = nlk_sk(sk); | |
1005 | int val; | |
1006 | ||
1007 | if (p->exclude_sk == sk) | |
1008 | goto out; | |
1009 | ||
15e47304 | 1010 | if (nlk->portid == p->portid || p->group - 1 >= nlk->ngroups || |
f7fa9b10 | 1011 | !test_bit(p->group - 1, nlk->groups)) |
1da177e4 LT |
1012 | goto out; |
1013 | ||
878628fb | 1014 | if (!net_eq(sock_net(sk), p->net)) |
b4b51029 EB |
1015 | goto out; |
1016 | ||
1da177e4 LT |
1017 | if (p->failure) { |
1018 | netlink_overrun(sk); | |
1019 | goto out; | |
1020 | } | |
1021 | ||
1022 | sock_hold(sk); | |
1023 | if (p->skb2 == NULL) { | |
68acc024 | 1024 | if (skb_shared(p->skb)) { |
1da177e4 LT |
1025 | p->skb2 = skb_clone(p->skb, p->allocation); |
1026 | } else { | |
68acc024 TC |
1027 | p->skb2 = skb_get(p->skb); |
1028 | /* | |
1029 | * skb ownership may have been set when | |
1030 | * delivered to a previous socket. | |
1031 | */ | |
1032 | skb_orphan(p->skb2); | |
1da177e4 LT |
1033 | } |
1034 | } | |
1035 | if (p->skb2 == NULL) { | |
1036 | netlink_overrun(sk); | |
1037 | /* Clone failed. Notify ALL listeners. */ | |
1038 | p->failure = 1; | |
be0c22a4 PNA |
1039 | if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR) |
1040 | p->delivery_failure = 1; | |
910a7e90 EB |
1041 | } else if (p->tx_filter && p->tx_filter(sk, p->skb2, p->tx_data)) { |
1042 | kfree_skb(p->skb2); | |
1043 | p->skb2 = NULL; | |
b1153f29 SH |
1044 | } else if (sk_filter(sk, p->skb2)) { |
1045 | kfree_skb(p->skb2); | |
1046 | p->skb2 = NULL; | |
1da177e4 LT |
1047 | } else if ((val = netlink_broadcast_deliver(sk, p->skb2)) < 0) { |
1048 | netlink_overrun(sk); | |
be0c22a4 PNA |
1049 | if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR) |
1050 | p->delivery_failure = 1; | |
1da177e4 LT |
1051 | } else { |
1052 | p->congested |= val; | |
1053 | p->delivered = 1; | |
1054 | p->skb2 = NULL; | |
1055 | } | |
1056 | sock_put(sk); | |
1057 | ||
1058 | out: | |
1059 | return 0; | |
1060 | } | |
1061 | ||
15e47304 | 1062 | int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb, u32 portid, |
910a7e90 EB |
1063 | u32 group, gfp_t allocation, |
1064 | int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data), | |
1065 | void *filter_data) | |
1da177e4 | 1066 | { |
3b1e0a65 | 1067 | struct net *net = sock_net(ssk); |
1da177e4 | 1068 | struct netlink_broadcast_data info; |
1da177e4 LT |
1069 | struct sock *sk; |
1070 | ||
1071 | skb = netlink_trim(skb, allocation); | |
1072 | ||
1073 | info.exclude_sk = ssk; | |
b4b51029 | 1074 | info.net = net; |
15e47304 | 1075 | info.portid = portid; |
1da177e4 LT |
1076 | info.group = group; |
1077 | info.failure = 0; | |
ff491a73 | 1078 | info.delivery_failure = 0; |
1da177e4 LT |
1079 | info.congested = 0; |
1080 | info.delivered = 0; | |
1081 | info.allocation = allocation; | |
1082 | info.skb = skb; | |
1083 | info.skb2 = NULL; | |
910a7e90 EB |
1084 | info.tx_filter = filter; |
1085 | info.tx_data = filter_data; | |
1da177e4 LT |
1086 | |
1087 | /* While we sleep in clone, do not allow to change socket list */ | |
1088 | ||
1089 | netlink_lock_table(); | |
1090 | ||
b67bfe0d | 1091 | sk_for_each_bound(sk, &nl_table[ssk->sk_protocol].mc_list) |
1da177e4 LT |
1092 | do_one_broadcast(sk, &info); |
1093 | ||
70d4bf6d | 1094 | consume_skb(skb); |
aa1c6a6f | 1095 | |
1da177e4 LT |
1096 | netlink_unlock_table(); |
1097 | ||
70d4bf6d NH |
1098 | if (info.delivery_failure) { |
1099 | kfree_skb(info.skb2); | |
ff491a73 | 1100 | return -ENOBUFS; |
658cb354 ED |
1101 | } |
1102 | consume_skb(info.skb2); | |
ff491a73 | 1103 | |
1da177e4 LT |
1104 | if (info.delivered) { |
1105 | if (info.congested && (allocation & __GFP_WAIT)) | |
1106 | yield(); | |
1107 | return 0; | |
1108 | } | |
1da177e4 LT |
1109 | return -ESRCH; |
1110 | } | |
910a7e90 EB |
1111 | EXPORT_SYMBOL(netlink_broadcast_filtered); |
1112 | ||
15e47304 | 1113 | int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 portid, |
910a7e90 EB |
1114 | u32 group, gfp_t allocation) |
1115 | { | |
15e47304 | 1116 | return netlink_broadcast_filtered(ssk, skb, portid, group, allocation, |
910a7e90 EB |
1117 | NULL, NULL); |
1118 | } | |
6ac552fd | 1119 | EXPORT_SYMBOL(netlink_broadcast); |
1da177e4 LT |
1120 | |
1121 | struct netlink_set_err_data { | |
1122 | struct sock *exclude_sk; | |
15e47304 | 1123 | u32 portid; |
1da177e4 LT |
1124 | u32 group; |
1125 | int code; | |
1126 | }; | |
1127 | ||
b57ef81f | 1128 | static int do_one_set_err(struct sock *sk, struct netlink_set_err_data *p) |
1da177e4 LT |
1129 | { |
1130 | struct netlink_sock *nlk = nlk_sk(sk); | |
1a50307b | 1131 | int ret = 0; |
1da177e4 LT |
1132 | |
1133 | if (sk == p->exclude_sk) | |
1134 | goto out; | |
1135 | ||
09ad9bc7 | 1136 | if (!net_eq(sock_net(sk), sock_net(p->exclude_sk))) |
b4b51029 EB |
1137 | goto out; |
1138 | ||
15e47304 | 1139 | if (nlk->portid == p->portid || p->group - 1 >= nlk->ngroups || |
f7fa9b10 | 1140 | !test_bit(p->group - 1, nlk->groups)) |
1da177e4 LT |
1141 | goto out; |
1142 | ||
1a50307b PNA |
1143 | if (p->code == ENOBUFS && nlk->flags & NETLINK_RECV_NO_ENOBUFS) { |
1144 | ret = 1; | |
1145 | goto out; | |
1146 | } | |
1147 | ||
1da177e4 LT |
1148 | sk->sk_err = p->code; |
1149 | sk->sk_error_report(sk); | |
1150 | out: | |
1a50307b | 1151 | return ret; |
1da177e4 LT |
1152 | } |
1153 | ||
4843b93c PNA |
1154 | /** |
1155 | * netlink_set_err - report error to broadcast listeners | |
1156 | * @ssk: the kernel netlink socket, as returned by netlink_kernel_create() | |
15e47304 | 1157 | * @portid: the PORTID of a process that we want to skip (if any) |
4843b93c PNA |
1158 | * @groups: the broadcast group that will notice the error |
1159 | * @code: error code, must be negative (as usual in kernelspace) | |
1a50307b PNA |
1160 | * |
1161 | * This function returns the number of broadcast listeners that have set the | |
1162 | * NETLINK_RECV_NO_ENOBUFS socket option. | |
4843b93c | 1163 | */ |
15e47304 | 1164 | int netlink_set_err(struct sock *ssk, u32 portid, u32 group, int code) |
1da177e4 LT |
1165 | { |
1166 | struct netlink_set_err_data info; | |
1da177e4 | 1167 | struct sock *sk; |
1a50307b | 1168 | int ret = 0; |
1da177e4 LT |
1169 | |
1170 | info.exclude_sk = ssk; | |
15e47304 | 1171 | info.portid = portid; |
1da177e4 | 1172 | info.group = group; |
4843b93c PNA |
1173 | /* sk->sk_err wants a positive error value */ |
1174 | info.code = -code; | |
1da177e4 LT |
1175 | |
1176 | read_lock(&nl_table_lock); | |
1177 | ||
b67bfe0d | 1178 | sk_for_each_bound(sk, &nl_table[ssk->sk_protocol].mc_list) |
1a50307b | 1179 | ret += do_one_set_err(sk, &info); |
1da177e4 LT |
1180 | |
1181 | read_unlock(&nl_table_lock); | |
1a50307b | 1182 | return ret; |
1da177e4 | 1183 | } |
dd5b6ce6 | 1184 | EXPORT_SYMBOL(netlink_set_err); |
1da177e4 | 1185 | |
84659eb5 JB |
1186 | /* must be called with netlink table grabbed */ |
1187 | static void netlink_update_socket_mc(struct netlink_sock *nlk, | |
1188 | unsigned int group, | |
1189 | int is_new) | |
1190 | { | |
1191 | int old, new = !!is_new, subscriptions; | |
1192 | ||
1193 | old = test_bit(group - 1, nlk->groups); | |
1194 | subscriptions = nlk->subscriptions - old + new; | |
1195 | if (new) | |
1196 | __set_bit(group - 1, nlk->groups); | |
1197 | else | |
1198 | __clear_bit(group - 1, nlk->groups); | |
1199 | netlink_update_subscriptions(&nlk->sk, subscriptions); | |
1200 | netlink_update_listeners(&nlk->sk); | |
1201 | } | |
1202 | ||
9a4595bc | 1203 | static int netlink_setsockopt(struct socket *sock, int level, int optname, |
b7058842 | 1204 | char __user *optval, unsigned int optlen) |
9a4595bc PM |
1205 | { |
1206 | struct sock *sk = sock->sk; | |
1207 | struct netlink_sock *nlk = nlk_sk(sk); | |
eb496534 JB |
1208 | unsigned int val = 0; |
1209 | int err; | |
9a4595bc PM |
1210 | |
1211 | if (level != SOL_NETLINK) | |
1212 | return -ENOPROTOOPT; | |
1213 | ||
1214 | if (optlen >= sizeof(int) && | |
eb496534 | 1215 | get_user(val, (unsigned int __user *)optval)) |
9a4595bc PM |
1216 | return -EFAULT; |
1217 | ||
1218 | switch (optname) { | |
1219 | case NETLINK_PKTINFO: | |
1220 | if (val) | |
1221 | nlk->flags |= NETLINK_RECV_PKTINFO; | |
1222 | else | |
1223 | nlk->flags &= ~NETLINK_RECV_PKTINFO; | |
1224 | err = 0; | |
1225 | break; | |
1226 | case NETLINK_ADD_MEMBERSHIP: | |
1227 | case NETLINK_DROP_MEMBERSHIP: { | |
9785e10a | 1228 | if (!netlink_capable(sock, NL_CFG_F_NONROOT_RECV)) |
9a4595bc | 1229 | return -EPERM; |
b4ff4f04 JB |
1230 | err = netlink_realloc_groups(sk); |
1231 | if (err) | |
1232 | return err; | |
9a4595bc PM |
1233 | if (!val || val - 1 >= nlk->ngroups) |
1234 | return -EINVAL; | |
1235 | netlink_table_grab(); | |
84659eb5 JB |
1236 | netlink_update_socket_mc(nlk, val, |
1237 | optname == NETLINK_ADD_MEMBERSHIP); | |
9a4595bc | 1238 | netlink_table_ungrab(); |
03292745 PNA |
1239 | |
1240 | if (nlk->netlink_bind) | |
1241 | nlk->netlink_bind(val); | |
1242 | ||
9a4595bc PM |
1243 | err = 0; |
1244 | break; | |
1245 | } | |
be0c22a4 PNA |
1246 | case NETLINK_BROADCAST_ERROR: |
1247 | if (val) | |
1248 | nlk->flags |= NETLINK_BROADCAST_SEND_ERROR; | |
1249 | else | |
1250 | nlk->flags &= ~NETLINK_BROADCAST_SEND_ERROR; | |
1251 | err = 0; | |
1252 | break; | |
38938bfe PNA |
1253 | case NETLINK_NO_ENOBUFS: |
1254 | if (val) { | |
1255 | nlk->flags |= NETLINK_RECV_NO_ENOBUFS; | |
cd967e05 | 1256 | clear_bit(NETLINK_CONGESTED, &nlk->state); |
38938bfe | 1257 | wake_up_interruptible(&nlk->wait); |
658cb354 | 1258 | } else { |
38938bfe | 1259 | nlk->flags &= ~NETLINK_RECV_NO_ENOBUFS; |
658cb354 | 1260 | } |
38938bfe PNA |
1261 | err = 0; |
1262 | break; | |
9a4595bc PM |
1263 | default: |
1264 | err = -ENOPROTOOPT; | |
1265 | } | |
1266 | return err; | |
1267 | } | |
1268 | ||
1269 | static int netlink_getsockopt(struct socket *sock, int level, int optname, | |
746fac4d | 1270 | char __user *optval, int __user *optlen) |
9a4595bc PM |
1271 | { |
1272 | struct sock *sk = sock->sk; | |
1273 | struct netlink_sock *nlk = nlk_sk(sk); | |
1274 | int len, val, err; | |
1275 | ||
1276 | if (level != SOL_NETLINK) | |
1277 | return -ENOPROTOOPT; | |
1278 | ||
1279 | if (get_user(len, optlen)) | |
1280 | return -EFAULT; | |
1281 | if (len < 0) | |
1282 | return -EINVAL; | |
1283 | ||
1284 | switch (optname) { | |
1285 | case NETLINK_PKTINFO: | |
1286 | if (len < sizeof(int)) | |
1287 | return -EINVAL; | |
1288 | len = sizeof(int); | |
1289 | val = nlk->flags & NETLINK_RECV_PKTINFO ? 1 : 0; | |
a27b58fe HC |
1290 | if (put_user(len, optlen) || |
1291 | put_user(val, optval)) | |
1292 | return -EFAULT; | |
9a4595bc PM |
1293 | err = 0; |
1294 | break; | |
be0c22a4 PNA |
1295 | case NETLINK_BROADCAST_ERROR: |
1296 | if (len < sizeof(int)) | |
1297 | return -EINVAL; | |
1298 | len = sizeof(int); | |
1299 | val = nlk->flags & NETLINK_BROADCAST_SEND_ERROR ? 1 : 0; | |
1300 | if (put_user(len, optlen) || | |
1301 | put_user(val, optval)) | |
1302 | return -EFAULT; | |
1303 | err = 0; | |
1304 | break; | |
38938bfe PNA |
1305 | case NETLINK_NO_ENOBUFS: |
1306 | if (len < sizeof(int)) | |
1307 | return -EINVAL; | |
1308 | len = sizeof(int); | |
1309 | val = nlk->flags & NETLINK_RECV_NO_ENOBUFS ? 1 : 0; | |
1310 | if (put_user(len, optlen) || | |
1311 | put_user(val, optval)) | |
1312 | return -EFAULT; | |
1313 | err = 0; | |
1314 | break; | |
9a4595bc PM |
1315 | default: |
1316 | err = -ENOPROTOOPT; | |
1317 | } | |
1318 | return err; | |
1319 | } | |
1320 | ||
1321 | static void netlink_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb) | |
1322 | { | |
1323 | struct nl_pktinfo info; | |
1324 | ||
1325 | info.group = NETLINK_CB(skb).dst_group; | |
1326 | put_cmsg(msg, SOL_NETLINK, NETLINK_PKTINFO, sizeof(info), &info); | |
1327 | } | |
1328 | ||
1da177e4 LT |
1329 | static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock, |
1330 | struct msghdr *msg, size_t len) | |
1331 | { | |
1332 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1333 | struct sock *sk = sock->sk; | |
1334 | struct netlink_sock *nlk = nlk_sk(sk); | |
6ac552fd | 1335 | struct sockaddr_nl *addr = msg->msg_name; |
15e47304 | 1336 | u32 dst_portid; |
d629b836 | 1337 | u32 dst_group; |
1da177e4 LT |
1338 | struct sk_buff *skb; |
1339 | int err; | |
1340 | struct scm_cookie scm; | |
1341 | ||
1342 | if (msg->msg_flags&MSG_OOB) | |
1343 | return -EOPNOTSUPP; | |
1344 | ||
16e57262 | 1345 | if (NULL == siocb->scm) |
1da177e4 | 1346 | siocb->scm = &scm; |
16e57262 | 1347 | |
e0e3cea4 | 1348 | err = scm_send(sock, msg, siocb->scm, true); |
1da177e4 LT |
1349 | if (err < 0) |
1350 | return err; | |
1351 | ||
1352 | if (msg->msg_namelen) { | |
b47030c7 | 1353 | err = -EINVAL; |
1da177e4 | 1354 | if (addr->nl_family != AF_NETLINK) |
b47030c7 | 1355 | goto out; |
15e47304 | 1356 | dst_portid = addr->nl_pid; |
d629b836 | 1357 | dst_group = ffs(addr->nl_groups); |
b47030c7 | 1358 | err = -EPERM; |
15e47304 | 1359 | if ((dst_group || dst_portid) && |
9785e10a | 1360 | !netlink_capable(sock, NL_CFG_F_NONROOT_SEND)) |
b47030c7 | 1361 | goto out; |
1da177e4 | 1362 | } else { |
15e47304 | 1363 | dst_portid = nlk->dst_portid; |
d629b836 | 1364 | dst_group = nlk->dst_group; |
1da177e4 LT |
1365 | } |
1366 | ||
15e47304 | 1367 | if (!nlk->portid) { |
1da177e4 LT |
1368 | err = netlink_autobind(sock); |
1369 | if (err) | |
1370 | goto out; | |
1371 | } | |
1372 | ||
1373 | err = -EMSGSIZE; | |
1374 | if (len > sk->sk_sndbuf - 32) | |
1375 | goto out; | |
1376 | err = -ENOBUFS; | |
339bf98f | 1377 | skb = alloc_skb(len, GFP_KERNEL); |
6ac552fd | 1378 | if (skb == NULL) |
1da177e4 LT |
1379 | goto out; |
1380 | ||
15e47304 | 1381 | NETLINK_CB(skb).portid = nlk->portid; |
d629b836 | 1382 | NETLINK_CB(skb).dst_group = dst_group; |
dbe9a417 | 1383 | NETLINK_CB(skb).creds = siocb->scm->creds; |
1da177e4 | 1384 | |
1da177e4 | 1385 | err = -EFAULT; |
6ac552fd | 1386 | if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) { |
1da177e4 LT |
1387 | kfree_skb(skb); |
1388 | goto out; | |
1389 | } | |
1390 | ||
1391 | err = security_netlink_send(sk, skb); | |
1392 | if (err) { | |
1393 | kfree_skb(skb); | |
1394 | goto out; | |
1395 | } | |
1396 | ||
d629b836 | 1397 | if (dst_group) { |
1da177e4 | 1398 | atomic_inc(&skb->users); |
15e47304 | 1399 | netlink_broadcast(sk, skb, dst_portid, dst_group, GFP_KERNEL); |
1da177e4 | 1400 | } |
15e47304 | 1401 | err = netlink_unicast(sk, skb, dst_portid, msg->msg_flags&MSG_DONTWAIT); |
1da177e4 LT |
1402 | |
1403 | out: | |
b47030c7 | 1404 | scm_destroy(siocb->scm); |
1da177e4 LT |
1405 | return err; |
1406 | } | |
1407 | ||
1408 | static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock, | |
1409 | struct msghdr *msg, size_t len, | |
1410 | int flags) | |
1411 | { | |
1412 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1413 | struct scm_cookie scm; | |
1414 | struct sock *sk = sock->sk; | |
1415 | struct netlink_sock *nlk = nlk_sk(sk); | |
1416 | int noblock = flags&MSG_DONTWAIT; | |
1417 | size_t copied; | |
68d6ac6d | 1418 | struct sk_buff *skb, *data_skb; |
b44d211e | 1419 | int err, ret; |
1da177e4 LT |
1420 | |
1421 | if (flags&MSG_OOB) | |
1422 | return -EOPNOTSUPP; | |
1423 | ||
1424 | copied = 0; | |
1425 | ||
6ac552fd PM |
1426 | skb = skb_recv_datagram(sk, flags, noblock, &err); |
1427 | if (skb == NULL) | |
1da177e4 LT |
1428 | goto out; |
1429 | ||
68d6ac6d JB |
1430 | data_skb = skb; |
1431 | ||
1dacc76d JB |
1432 | #ifdef CONFIG_COMPAT_NETLINK_MESSAGES |
1433 | if (unlikely(skb_shinfo(skb)->frag_list)) { | |
1dacc76d | 1434 | /* |
68d6ac6d JB |
1435 | * If this skb has a frag_list, then here that means that we |
1436 | * will have to use the frag_list skb's data for compat tasks | |
1437 | * and the regular skb's data for normal (non-compat) tasks. | |
1dacc76d | 1438 | * |
68d6ac6d JB |
1439 | * If we need to send the compat skb, assign it to the |
1440 | * 'data_skb' variable so that it will be used below for data | |
1441 | * copying. We keep 'skb' for everything else, including | |
1442 | * freeing both later. | |
1dacc76d | 1443 | */ |
68d6ac6d JB |
1444 | if (flags & MSG_CMSG_COMPAT) |
1445 | data_skb = skb_shinfo(skb)->frag_list; | |
1dacc76d JB |
1446 | } |
1447 | #endif | |
1448 | ||
1da177e4 LT |
1449 | msg->msg_namelen = 0; |
1450 | ||
68d6ac6d | 1451 | copied = data_skb->len; |
1da177e4 LT |
1452 | if (len < copied) { |
1453 | msg->msg_flags |= MSG_TRUNC; | |
1454 | copied = len; | |
1455 | } | |
1456 | ||
68d6ac6d JB |
1457 | skb_reset_transport_header(data_skb); |
1458 | err = skb_copy_datagram_iovec(data_skb, 0, msg->msg_iov, copied); | |
1da177e4 LT |
1459 | |
1460 | if (msg->msg_name) { | |
6ac552fd | 1461 | struct sockaddr_nl *addr = (struct sockaddr_nl *)msg->msg_name; |
1da177e4 LT |
1462 | addr->nl_family = AF_NETLINK; |
1463 | addr->nl_pad = 0; | |
15e47304 | 1464 | addr->nl_pid = NETLINK_CB(skb).portid; |
d629b836 | 1465 | addr->nl_groups = netlink_group_mask(NETLINK_CB(skb).dst_group); |
1da177e4 LT |
1466 | msg->msg_namelen = sizeof(*addr); |
1467 | } | |
1468 | ||
cc9a06cd PM |
1469 | if (nlk->flags & NETLINK_RECV_PKTINFO) |
1470 | netlink_cmsg_recv_pktinfo(msg, skb); | |
1471 | ||
1da177e4 LT |
1472 | if (NULL == siocb->scm) { |
1473 | memset(&scm, 0, sizeof(scm)); | |
1474 | siocb->scm = &scm; | |
1475 | } | |
1476 | siocb->scm->creds = *NETLINK_CREDS(skb); | |
188ccb55 | 1477 | if (flags & MSG_TRUNC) |
68d6ac6d | 1478 | copied = data_skb->len; |
daa3766e | 1479 | |
1da177e4 LT |
1480 | skb_free_datagram(sk, skb); |
1481 | ||
b44d211e AV |
1482 | if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) { |
1483 | ret = netlink_dump(sk); | |
1484 | if (ret) { | |
1485 | sk->sk_err = ret; | |
1486 | sk->sk_error_report(sk); | |
1487 | } | |
1488 | } | |
1da177e4 LT |
1489 | |
1490 | scm_recv(sock, msg, siocb->scm, flags); | |
1da177e4 LT |
1491 | out: |
1492 | netlink_rcv_wake(sk); | |
1493 | return err ? : copied; | |
1494 | } | |
1495 | ||
1496 | static void netlink_data_ready(struct sock *sk, int len) | |
1497 | { | |
cd40b7d3 | 1498 | BUG(); |
1da177e4 LT |
1499 | } |
1500 | ||
1501 | /* | |
746fac4d | 1502 | * We export these functions to other modules. They provide a |
1da177e4 LT |
1503 | * complete set of kernel non-blocking support for message |
1504 | * queueing. | |
1505 | */ | |
1506 | ||
1507 | struct sock * | |
9f00d977 PNA |
1508 | __netlink_kernel_create(struct net *net, int unit, struct module *module, |
1509 | struct netlink_kernel_cfg *cfg) | |
1da177e4 LT |
1510 | { |
1511 | struct socket *sock; | |
1512 | struct sock *sk; | |
77247bbb | 1513 | struct netlink_sock *nlk; |
5c398dc8 | 1514 | struct listeners *listeners = NULL; |
a31f2d17 PNA |
1515 | struct mutex *cb_mutex = cfg ? cfg->cb_mutex : NULL; |
1516 | unsigned int groups; | |
1da177e4 | 1517 | |
fab2caf6 | 1518 | BUG_ON(!nl_table); |
1da177e4 | 1519 | |
6ac552fd | 1520 | if (unit < 0 || unit >= MAX_LINKS) |
1da177e4 LT |
1521 | return NULL; |
1522 | ||
1523 | if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock)) | |
1524 | return NULL; | |
1525 | ||
23fe1866 PE |
1526 | /* |
1527 | * We have to just have a reference on the net from sk, but don't | |
1528 | * get_net it. Besides, we cannot get and then put the net here. | |
1529 | * So we create one inside init_net and the move it to net. | |
1530 | */ | |
1531 | ||
1532 | if (__netlink_create(&init_net, sock, cb_mutex, unit) < 0) | |
1533 | goto out_sock_release_nosk; | |
1534 | ||
1535 | sk = sock->sk; | |
edf02087 | 1536 | sk_change_net(sk, net); |
4fdb3bb7 | 1537 | |
a31f2d17 | 1538 | if (!cfg || cfg->groups < 32) |
4277a083 | 1539 | groups = 32; |
a31f2d17 PNA |
1540 | else |
1541 | groups = cfg->groups; | |
4277a083 | 1542 | |
5c398dc8 | 1543 | listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL); |
4277a083 PM |
1544 | if (!listeners) |
1545 | goto out_sock_release; | |
1546 | ||
1da177e4 | 1547 | sk->sk_data_ready = netlink_data_ready; |
a31f2d17 PNA |
1548 | if (cfg && cfg->input) |
1549 | nlk_sk(sk)->netlink_rcv = cfg->input; | |
1da177e4 | 1550 | |
b4b51029 | 1551 | if (netlink_insert(sk, net, 0)) |
77247bbb | 1552 | goto out_sock_release; |
4fdb3bb7 | 1553 | |
77247bbb PM |
1554 | nlk = nlk_sk(sk); |
1555 | nlk->flags |= NETLINK_KERNEL_SOCKET; | |
4fdb3bb7 | 1556 | |
4fdb3bb7 | 1557 | netlink_table_grab(); |
b4b51029 EB |
1558 | if (!nl_table[unit].registered) { |
1559 | nl_table[unit].groups = groups; | |
5c398dc8 | 1560 | rcu_assign_pointer(nl_table[unit].listeners, listeners); |
b4b51029 EB |
1561 | nl_table[unit].cb_mutex = cb_mutex; |
1562 | nl_table[unit].module = module; | |
9785e10a PNA |
1563 | if (cfg) { |
1564 | nl_table[unit].bind = cfg->bind; | |
1565 | nl_table[unit].flags = cfg->flags; | |
1566 | } | |
b4b51029 | 1567 | nl_table[unit].registered = 1; |
f937f1f4 JJ |
1568 | } else { |
1569 | kfree(listeners); | |
869e58f8 | 1570 | nl_table[unit].registered++; |
b4b51029 | 1571 | } |
4fdb3bb7 | 1572 | netlink_table_ungrab(); |
77247bbb PM |
1573 | return sk; |
1574 | ||
4fdb3bb7 | 1575 | out_sock_release: |
4277a083 | 1576 | kfree(listeners); |
9dfbec1f | 1577 | netlink_kernel_release(sk); |
23fe1866 PE |
1578 | return NULL; |
1579 | ||
1580 | out_sock_release_nosk: | |
4fdb3bb7 | 1581 | sock_release(sock); |
77247bbb | 1582 | return NULL; |
1da177e4 | 1583 | } |
9f00d977 | 1584 | EXPORT_SYMBOL(__netlink_kernel_create); |
b7c6ba6e DL |
1585 | |
1586 | void | |
1587 | netlink_kernel_release(struct sock *sk) | |
1588 | { | |
edf02087 | 1589 | sk_release_kernel(sk); |
b7c6ba6e DL |
1590 | } |
1591 | EXPORT_SYMBOL(netlink_kernel_release); | |
1592 | ||
d136f1bd | 1593 | int __netlink_change_ngroups(struct sock *sk, unsigned int groups) |
b4ff4f04 | 1594 | { |
5c398dc8 | 1595 | struct listeners *new, *old; |
b4ff4f04 | 1596 | struct netlink_table *tbl = &nl_table[sk->sk_protocol]; |
b4ff4f04 JB |
1597 | |
1598 | if (groups < 32) | |
1599 | groups = 32; | |
1600 | ||
b4ff4f04 | 1601 | if (NLGRPSZ(tbl->groups) < NLGRPSZ(groups)) { |
5c398dc8 ED |
1602 | new = kzalloc(sizeof(*new) + NLGRPSZ(groups), GFP_ATOMIC); |
1603 | if (!new) | |
d136f1bd | 1604 | return -ENOMEM; |
6d772ac5 | 1605 | old = nl_deref_protected(tbl->listeners); |
5c398dc8 ED |
1606 | memcpy(new->masks, old->masks, NLGRPSZ(tbl->groups)); |
1607 | rcu_assign_pointer(tbl->listeners, new); | |
1608 | ||
37b6b935 | 1609 | kfree_rcu(old, rcu); |
b4ff4f04 JB |
1610 | } |
1611 | tbl->groups = groups; | |
1612 | ||
d136f1bd JB |
1613 | return 0; |
1614 | } | |
1615 | ||
1616 | /** | |
1617 | * netlink_change_ngroups - change number of multicast groups | |
1618 | * | |
1619 | * This changes the number of multicast groups that are available | |
1620 | * on a certain netlink family. Note that it is not possible to | |
1621 | * change the number of groups to below 32. Also note that it does | |
1622 | * not implicitly call netlink_clear_multicast_users() when the | |
1623 | * number of groups is reduced. | |
1624 | * | |
1625 | * @sk: The kernel netlink socket, as returned by netlink_kernel_create(). | |
1626 | * @groups: The new number of groups. | |
1627 | */ | |
1628 | int netlink_change_ngroups(struct sock *sk, unsigned int groups) | |
1629 | { | |
1630 | int err; | |
1631 | ||
1632 | netlink_table_grab(); | |
1633 | err = __netlink_change_ngroups(sk, groups); | |
b4ff4f04 | 1634 | netlink_table_ungrab(); |
d136f1bd | 1635 | |
b4ff4f04 JB |
1636 | return err; |
1637 | } | |
b4ff4f04 | 1638 | |
b8273570 JB |
1639 | void __netlink_clear_multicast_users(struct sock *ksk, unsigned int group) |
1640 | { | |
1641 | struct sock *sk; | |
b8273570 JB |
1642 | struct netlink_table *tbl = &nl_table[ksk->sk_protocol]; |
1643 | ||
b67bfe0d | 1644 | sk_for_each_bound(sk, &tbl->mc_list) |
b8273570 JB |
1645 | netlink_update_socket_mc(nlk_sk(sk), group, 0); |
1646 | } | |
1647 | ||
84659eb5 JB |
1648 | /** |
1649 | * netlink_clear_multicast_users - kick off multicast listeners | |
1650 | * | |
1651 | * This function removes all listeners from the given group. | |
1652 | * @ksk: The kernel netlink socket, as returned by | |
1653 | * netlink_kernel_create(). | |
1654 | * @group: The multicast group to clear. | |
1655 | */ | |
1656 | void netlink_clear_multicast_users(struct sock *ksk, unsigned int group) | |
1657 | { | |
84659eb5 | 1658 | netlink_table_grab(); |
b8273570 | 1659 | __netlink_clear_multicast_users(ksk, group); |
84659eb5 JB |
1660 | netlink_table_ungrab(); |
1661 | } | |
84659eb5 | 1662 | |
a46621a3 | 1663 | struct nlmsghdr * |
15e47304 | 1664 | __nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int flags) |
a46621a3 DV |
1665 | { |
1666 | struct nlmsghdr *nlh; | |
573ce260 | 1667 | int size = nlmsg_msg_size(len); |
a46621a3 DV |
1668 | |
1669 | nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size)); | |
1670 | nlh->nlmsg_type = type; | |
1671 | nlh->nlmsg_len = size; | |
1672 | nlh->nlmsg_flags = flags; | |
15e47304 | 1673 | nlh->nlmsg_pid = portid; |
a46621a3 DV |
1674 | nlh->nlmsg_seq = seq; |
1675 | if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0) | |
573ce260 | 1676 | memset(nlmsg_data(nlh) + len, 0, NLMSG_ALIGN(size) - size); |
a46621a3 DV |
1677 | return nlh; |
1678 | } | |
1679 | EXPORT_SYMBOL(__nlmsg_put); | |
1680 | ||
1da177e4 LT |
1681 | /* |
1682 | * It looks a bit ugly. | |
1683 | * It would be better to create kernel thread. | |
1684 | */ | |
1685 | ||
1686 | static int netlink_dump(struct sock *sk) | |
1687 | { | |
1688 | struct netlink_sock *nlk = nlk_sk(sk); | |
1689 | struct netlink_callback *cb; | |
c7ac8679 | 1690 | struct sk_buff *skb = NULL; |
1da177e4 | 1691 | struct nlmsghdr *nlh; |
bf8b79e4 | 1692 | int len, err = -ENOBUFS; |
c7ac8679 | 1693 | int alloc_size; |
1da177e4 | 1694 | |
af65bdfc | 1695 | mutex_lock(nlk->cb_mutex); |
1da177e4 LT |
1696 | |
1697 | cb = nlk->cb; | |
1698 | if (cb == NULL) { | |
bf8b79e4 TG |
1699 | err = -EINVAL; |
1700 | goto errout_skb; | |
1da177e4 LT |
1701 | } |
1702 | ||
c7ac8679 GR |
1703 | alloc_size = max_t(int, cb->min_dump_alloc, NLMSG_GOODSIZE); |
1704 | ||
1705 | skb = sock_rmalloc(sk, alloc_size, 0, GFP_KERNEL); | |
1706 | if (!skb) | |
c63d6ea3 | 1707 | goto errout_skb; |
c7ac8679 | 1708 | |
1da177e4 LT |
1709 | len = cb->dump(skb, cb); |
1710 | ||
1711 | if (len > 0) { | |
af65bdfc | 1712 | mutex_unlock(nlk->cb_mutex); |
b1153f29 SH |
1713 | |
1714 | if (sk_filter(sk, skb)) | |
1715 | kfree_skb(skb); | |
4a7e7c2a ED |
1716 | else |
1717 | __netlink_sendskb(sk, skb); | |
1da177e4 LT |
1718 | return 0; |
1719 | } | |
1720 | ||
bf8b79e4 TG |
1721 | nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI); |
1722 | if (!nlh) | |
1723 | goto errout_skb; | |
1724 | ||
670dc283 JB |
1725 | nl_dump_check_consistent(cb, nlh); |
1726 | ||
bf8b79e4 TG |
1727 | memcpy(nlmsg_data(nlh), &len, sizeof(len)); |
1728 | ||
b1153f29 SH |
1729 | if (sk_filter(sk, skb)) |
1730 | kfree_skb(skb); | |
4a7e7c2a ED |
1731 | else |
1732 | __netlink_sendskb(sk, skb); | |
1da177e4 | 1733 | |
a8f74b22 TG |
1734 | if (cb->done) |
1735 | cb->done(cb); | |
1da177e4 | 1736 | nlk->cb = NULL; |
af65bdfc | 1737 | mutex_unlock(nlk->cb_mutex); |
1da177e4 | 1738 | |
6dc878a8 | 1739 | module_put(cb->module); |
bfb253c9 | 1740 | netlink_consume_callback(cb); |
1da177e4 | 1741 | return 0; |
1797754e | 1742 | |
bf8b79e4 | 1743 | errout_skb: |
af65bdfc | 1744 | mutex_unlock(nlk->cb_mutex); |
bf8b79e4 | 1745 | kfree_skb(skb); |
bf8b79e4 | 1746 | return err; |
1da177e4 LT |
1747 | } |
1748 | ||
6dc878a8 G |
1749 | int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb, |
1750 | const struct nlmsghdr *nlh, | |
1751 | struct netlink_dump_control *control) | |
1da177e4 LT |
1752 | { |
1753 | struct netlink_callback *cb; | |
1754 | struct sock *sk; | |
1755 | struct netlink_sock *nlk; | |
b44d211e | 1756 | int ret; |
1da177e4 | 1757 | |
0da974f4 | 1758 | cb = kzalloc(sizeof(*cb), GFP_KERNEL); |
1da177e4 LT |
1759 | if (cb == NULL) |
1760 | return -ENOBUFS; | |
1761 | ||
80d326fa PNA |
1762 | cb->dump = control->dump; |
1763 | cb->done = control->done; | |
1da177e4 | 1764 | cb->nlh = nlh; |
7175c883 | 1765 | cb->data = control->data; |
6dc878a8 | 1766 | cb->module = control->module; |
80d326fa | 1767 | cb->min_dump_alloc = control->min_dump_alloc; |
1da177e4 LT |
1768 | atomic_inc(&skb->users); |
1769 | cb->skb = skb; | |
1770 | ||
15e47304 | 1771 | sk = netlink_lookup(sock_net(ssk), ssk->sk_protocol, NETLINK_CB(skb).portid); |
1da177e4 LT |
1772 | if (sk == NULL) { |
1773 | netlink_destroy_callback(cb); | |
1774 | return -ECONNREFUSED; | |
1775 | } | |
1776 | nlk = nlk_sk(sk); | |
6dc878a8 | 1777 | |
af65bdfc | 1778 | mutex_lock(nlk->cb_mutex); |
6dc878a8 | 1779 | /* A dump is in progress... */ |
3f660d66 | 1780 | if (nlk->cb) { |
af65bdfc | 1781 | mutex_unlock(nlk->cb_mutex); |
1da177e4 | 1782 | netlink_destroy_callback(cb); |
6dc878a8 G |
1783 | ret = -EBUSY; |
1784 | goto out; | |
1da177e4 | 1785 | } |
6dc878a8 G |
1786 | /* add reference of module which cb->dump belongs to */ |
1787 | if (!try_module_get(cb->module)) { | |
1788 | mutex_unlock(nlk->cb_mutex); | |
1789 | netlink_destroy_callback(cb); | |
1790 | ret = -EPROTONOSUPPORT; | |
1791 | goto out; | |
1792 | } | |
1793 | ||
1da177e4 | 1794 | nlk->cb = cb; |
af65bdfc | 1795 | mutex_unlock(nlk->cb_mutex); |
1da177e4 | 1796 | |
b44d211e | 1797 | ret = netlink_dump(sk); |
6dc878a8 | 1798 | out: |
1da177e4 | 1799 | sock_put(sk); |
5c58298c | 1800 | |
b44d211e AV |
1801 | if (ret) |
1802 | return ret; | |
1803 | ||
5c58298c DL |
1804 | /* We successfully started a dump, by returning -EINTR we |
1805 | * signal not to send ACK even if it was requested. | |
1806 | */ | |
1807 | return -EINTR; | |
1da177e4 | 1808 | } |
6dc878a8 | 1809 | EXPORT_SYMBOL(__netlink_dump_start); |
1da177e4 LT |
1810 | |
1811 | void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err) | |
1812 | { | |
1813 | struct sk_buff *skb; | |
1814 | struct nlmsghdr *rep; | |
1815 | struct nlmsgerr *errmsg; | |
339bf98f | 1816 | size_t payload = sizeof(*errmsg); |
1da177e4 | 1817 | |
339bf98f TG |
1818 | /* error messages get the original request appened */ |
1819 | if (err) | |
1820 | payload += nlmsg_len(nlh); | |
1da177e4 | 1821 | |
339bf98f | 1822 | skb = nlmsg_new(payload, GFP_KERNEL); |
1da177e4 LT |
1823 | if (!skb) { |
1824 | struct sock *sk; | |
1825 | ||
3b1e0a65 | 1826 | sk = netlink_lookup(sock_net(in_skb->sk), |
b4b51029 | 1827 | in_skb->sk->sk_protocol, |
15e47304 | 1828 | NETLINK_CB(in_skb).portid); |
1da177e4 LT |
1829 | if (sk) { |
1830 | sk->sk_err = ENOBUFS; | |
1831 | sk->sk_error_report(sk); | |
1832 | sock_put(sk); | |
1833 | } | |
1834 | return; | |
1835 | } | |
1836 | ||
15e47304 | 1837 | rep = __nlmsg_put(skb, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, |
5dba93ae | 1838 | NLMSG_ERROR, payload, 0); |
bf8b79e4 | 1839 | errmsg = nlmsg_data(rep); |
1da177e4 | 1840 | errmsg->error = err; |
bf8b79e4 | 1841 | memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(*nlh)); |
15e47304 | 1842 | netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).portid, MSG_DONTWAIT); |
1da177e4 | 1843 | } |
6ac552fd | 1844 | EXPORT_SYMBOL(netlink_ack); |
1da177e4 | 1845 | |
cd40b7d3 | 1846 | int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *, |
1d00a4eb | 1847 | struct nlmsghdr *)) |
82ace47a | 1848 | { |
82ace47a TG |
1849 | struct nlmsghdr *nlh; |
1850 | int err; | |
1851 | ||
1852 | while (skb->len >= nlmsg_total_size(0)) { | |
cd40b7d3 DL |
1853 | int msglen; |
1854 | ||
b529ccf2 | 1855 | nlh = nlmsg_hdr(skb); |
d35b6856 | 1856 | err = 0; |
82ace47a | 1857 | |
ad8e4b75 | 1858 | if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len) |
82ace47a TG |
1859 | return 0; |
1860 | ||
d35b6856 TG |
1861 | /* Only requests are handled by the kernel */ |
1862 | if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) | |
5c58298c | 1863 | goto ack; |
45e7ae7f TG |
1864 | |
1865 | /* Skip control messages */ | |
1866 | if (nlh->nlmsg_type < NLMSG_MIN_TYPE) | |
5c58298c | 1867 | goto ack; |
d35b6856 | 1868 | |
1d00a4eb | 1869 | err = cb(skb, nlh); |
5c58298c DL |
1870 | if (err == -EINTR) |
1871 | goto skip; | |
1872 | ||
1873 | ack: | |
d35b6856 | 1874 | if (nlh->nlmsg_flags & NLM_F_ACK || err) |
82ace47a | 1875 | netlink_ack(skb, nlh, err); |
82ace47a | 1876 | |
5c58298c | 1877 | skip: |
6ac552fd | 1878 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); |
cd40b7d3 DL |
1879 | if (msglen > skb->len) |
1880 | msglen = skb->len; | |
1881 | skb_pull(skb, msglen); | |
82ace47a TG |
1882 | } |
1883 | ||
1884 | return 0; | |
1885 | } | |
6ac552fd | 1886 | EXPORT_SYMBOL(netlink_rcv_skb); |
82ace47a | 1887 | |
d387f6ad TG |
1888 | /** |
1889 | * nlmsg_notify - send a notification netlink message | |
1890 | * @sk: netlink socket to use | |
1891 | * @skb: notification message | |
15e47304 | 1892 | * @portid: destination netlink portid for reports or 0 |
d387f6ad TG |
1893 | * @group: destination multicast group or 0 |
1894 | * @report: 1 to report back, 0 to disable | |
1895 | * @flags: allocation flags | |
1896 | */ | |
15e47304 | 1897 | int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid, |
d387f6ad TG |
1898 | unsigned int group, int report, gfp_t flags) |
1899 | { | |
1900 | int err = 0; | |
1901 | ||
1902 | if (group) { | |
15e47304 | 1903 | int exclude_portid = 0; |
d387f6ad TG |
1904 | |
1905 | if (report) { | |
1906 | atomic_inc(&skb->users); | |
15e47304 | 1907 | exclude_portid = portid; |
d387f6ad TG |
1908 | } |
1909 | ||
1ce85fe4 PNA |
1910 | /* errors reported via destination sk->sk_err, but propagate |
1911 | * delivery errors if NETLINK_BROADCAST_ERROR flag is set */ | |
15e47304 | 1912 | err = nlmsg_multicast(sk, skb, exclude_portid, group, flags); |
d387f6ad TG |
1913 | } |
1914 | ||
1ce85fe4 PNA |
1915 | if (report) { |
1916 | int err2; | |
1917 | ||
15e47304 | 1918 | err2 = nlmsg_unicast(sk, skb, portid); |
1ce85fe4 PNA |
1919 | if (!err || err == -ESRCH) |
1920 | err = err2; | |
1921 | } | |
d387f6ad TG |
1922 | |
1923 | return err; | |
1924 | } | |
6ac552fd | 1925 | EXPORT_SYMBOL(nlmsg_notify); |
d387f6ad | 1926 | |
1da177e4 LT |
1927 | #ifdef CONFIG_PROC_FS |
1928 | struct nl_seq_iter { | |
e372c414 | 1929 | struct seq_net_private p; |
1da177e4 LT |
1930 | int link; |
1931 | int hash_idx; | |
1932 | }; | |
1933 | ||
1934 | static struct sock *netlink_seq_socket_idx(struct seq_file *seq, loff_t pos) | |
1935 | { | |
1936 | struct nl_seq_iter *iter = seq->private; | |
1937 | int i, j; | |
1938 | struct sock *s; | |
1da177e4 LT |
1939 | loff_t off = 0; |
1940 | ||
6ac552fd | 1941 | for (i = 0; i < MAX_LINKS; i++) { |
15e47304 | 1942 | struct nl_portid_hash *hash = &nl_table[i].hash; |
1da177e4 LT |
1943 | |
1944 | for (j = 0; j <= hash->mask; j++) { | |
b67bfe0d | 1945 | sk_for_each(s, &hash->table[j]) { |
1218854a | 1946 | if (sock_net(s) != seq_file_net(seq)) |
b4b51029 | 1947 | continue; |
1da177e4 LT |
1948 | if (off == pos) { |
1949 | iter->link = i; | |
1950 | iter->hash_idx = j; | |
1951 | return s; | |
1952 | } | |
1953 | ++off; | |
1954 | } | |
1955 | } | |
1956 | } | |
1957 | return NULL; | |
1958 | } | |
1959 | ||
1960 | static void *netlink_seq_start(struct seq_file *seq, loff_t *pos) | |
9a429c49 | 1961 | __acquires(nl_table_lock) |
1da177e4 LT |
1962 | { |
1963 | read_lock(&nl_table_lock); | |
1964 | return *pos ? netlink_seq_socket_idx(seq, *pos - 1) : SEQ_START_TOKEN; | |
1965 | } | |
1966 | ||
1967 | static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
1968 | { | |
1969 | struct sock *s; | |
1970 | struct nl_seq_iter *iter; | |
1971 | int i, j; | |
1972 | ||
1973 | ++*pos; | |
1974 | ||
1975 | if (v == SEQ_START_TOKEN) | |
1976 | return netlink_seq_socket_idx(seq, 0); | |
746fac4d | 1977 | |
b4b51029 EB |
1978 | iter = seq->private; |
1979 | s = v; | |
1980 | do { | |
1981 | s = sk_next(s); | |
1218854a | 1982 | } while (s && sock_net(s) != seq_file_net(seq)); |
1da177e4 LT |
1983 | if (s) |
1984 | return s; | |
1985 | ||
1da177e4 LT |
1986 | i = iter->link; |
1987 | j = iter->hash_idx + 1; | |
1988 | ||
1989 | do { | |
15e47304 | 1990 | struct nl_portid_hash *hash = &nl_table[i].hash; |
1da177e4 LT |
1991 | |
1992 | for (; j <= hash->mask; j++) { | |
1993 | s = sk_head(&hash->table[j]); | |
1218854a | 1994 | while (s && sock_net(s) != seq_file_net(seq)) |
b4b51029 | 1995 | s = sk_next(s); |
1da177e4 LT |
1996 | if (s) { |
1997 | iter->link = i; | |
1998 | iter->hash_idx = j; | |
1999 | return s; | |
2000 | } | |
2001 | } | |
2002 | ||
2003 | j = 0; | |
2004 | } while (++i < MAX_LINKS); | |
2005 | ||
2006 | return NULL; | |
2007 | } | |
2008 | ||
2009 | static void netlink_seq_stop(struct seq_file *seq, void *v) | |
9a429c49 | 2010 | __releases(nl_table_lock) |
1da177e4 LT |
2011 | { |
2012 | read_unlock(&nl_table_lock); | |
2013 | } | |
2014 | ||
2015 | ||
2016 | static int netlink_seq_show(struct seq_file *seq, void *v) | |
2017 | { | |
658cb354 | 2018 | if (v == SEQ_START_TOKEN) { |
1da177e4 LT |
2019 | seq_puts(seq, |
2020 | "sk Eth Pid Groups " | |
cf0aa4e0 | 2021 | "Rmem Wmem Dump Locks Drops Inode\n"); |
658cb354 | 2022 | } else { |
1da177e4 LT |
2023 | struct sock *s = v; |
2024 | struct netlink_sock *nlk = nlk_sk(s); | |
2025 | ||
9f1e0ad0 | 2026 | seq_printf(seq, "%pK %-3d %-6u %08x %-8d %-8d %pK %-8d %-8d %-8lu\n", |
1da177e4 LT |
2027 | s, |
2028 | s->sk_protocol, | |
15e47304 | 2029 | nlk->portid, |
513c2500 | 2030 | nlk->groups ? (u32)nlk->groups[0] : 0, |
31e6d363 ED |
2031 | sk_rmem_alloc_get(s), |
2032 | sk_wmem_alloc_get(s), | |
1da177e4 | 2033 | nlk->cb, |
38938bfe | 2034 | atomic_read(&s->sk_refcnt), |
cf0aa4e0 MY |
2035 | atomic_read(&s->sk_drops), |
2036 | sock_i_ino(s) | |
1da177e4 LT |
2037 | ); |
2038 | ||
2039 | } | |
2040 | return 0; | |
2041 | } | |
2042 | ||
56b3d975 | 2043 | static const struct seq_operations netlink_seq_ops = { |
1da177e4 LT |
2044 | .start = netlink_seq_start, |
2045 | .next = netlink_seq_next, | |
2046 | .stop = netlink_seq_stop, | |
2047 | .show = netlink_seq_show, | |
2048 | }; | |
2049 | ||
2050 | ||
2051 | static int netlink_seq_open(struct inode *inode, struct file *file) | |
2052 | { | |
e372c414 DL |
2053 | return seq_open_net(inode, file, &netlink_seq_ops, |
2054 | sizeof(struct nl_seq_iter)); | |
b4b51029 EB |
2055 | } |
2056 | ||
da7071d7 | 2057 | static const struct file_operations netlink_seq_fops = { |
1da177e4 LT |
2058 | .owner = THIS_MODULE, |
2059 | .open = netlink_seq_open, | |
2060 | .read = seq_read, | |
2061 | .llseek = seq_lseek, | |
e372c414 | 2062 | .release = seq_release_net, |
1da177e4 LT |
2063 | }; |
2064 | ||
2065 | #endif | |
2066 | ||
2067 | int netlink_register_notifier(struct notifier_block *nb) | |
2068 | { | |
e041c683 | 2069 | return atomic_notifier_chain_register(&netlink_chain, nb); |
1da177e4 | 2070 | } |
6ac552fd | 2071 | EXPORT_SYMBOL(netlink_register_notifier); |
1da177e4 LT |
2072 | |
2073 | int netlink_unregister_notifier(struct notifier_block *nb) | |
2074 | { | |
e041c683 | 2075 | return atomic_notifier_chain_unregister(&netlink_chain, nb); |
1da177e4 | 2076 | } |
6ac552fd | 2077 | EXPORT_SYMBOL(netlink_unregister_notifier); |
746fac4d | 2078 | |
90ddc4f0 | 2079 | static const struct proto_ops netlink_ops = { |
1da177e4 LT |
2080 | .family = PF_NETLINK, |
2081 | .owner = THIS_MODULE, | |
2082 | .release = netlink_release, | |
2083 | .bind = netlink_bind, | |
2084 | .connect = netlink_connect, | |
2085 | .socketpair = sock_no_socketpair, | |
2086 | .accept = sock_no_accept, | |
2087 | .getname = netlink_getname, | |
2088 | .poll = datagram_poll, | |
2089 | .ioctl = sock_no_ioctl, | |
2090 | .listen = sock_no_listen, | |
2091 | .shutdown = sock_no_shutdown, | |
9a4595bc PM |
2092 | .setsockopt = netlink_setsockopt, |
2093 | .getsockopt = netlink_getsockopt, | |
1da177e4 LT |
2094 | .sendmsg = netlink_sendmsg, |
2095 | .recvmsg = netlink_recvmsg, | |
2096 | .mmap = sock_no_mmap, | |
2097 | .sendpage = sock_no_sendpage, | |
2098 | }; | |
2099 | ||
ec1b4cf7 | 2100 | static const struct net_proto_family netlink_family_ops = { |
1da177e4 LT |
2101 | .family = PF_NETLINK, |
2102 | .create = netlink_create, | |
2103 | .owner = THIS_MODULE, /* for consistency 8) */ | |
2104 | }; | |
2105 | ||
4665079c | 2106 | static int __net_init netlink_net_init(struct net *net) |
b4b51029 EB |
2107 | { |
2108 | #ifdef CONFIG_PROC_FS | |
d4beaa66 | 2109 | if (!proc_create("netlink", 0, net->proc_net, &netlink_seq_fops)) |
b4b51029 EB |
2110 | return -ENOMEM; |
2111 | #endif | |
2112 | return 0; | |
2113 | } | |
2114 | ||
4665079c | 2115 | static void __net_exit netlink_net_exit(struct net *net) |
b4b51029 EB |
2116 | { |
2117 | #ifdef CONFIG_PROC_FS | |
ece31ffd | 2118 | remove_proc_entry("netlink", net->proc_net); |
b4b51029 EB |
2119 | #endif |
2120 | } | |
2121 | ||
b963ea89 DM |
2122 | static void __init netlink_add_usersock_entry(void) |
2123 | { | |
5c398dc8 | 2124 | struct listeners *listeners; |
b963ea89 DM |
2125 | int groups = 32; |
2126 | ||
5c398dc8 | 2127 | listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL); |
b963ea89 | 2128 | if (!listeners) |
5c398dc8 | 2129 | panic("netlink_add_usersock_entry: Cannot allocate listeners\n"); |
b963ea89 DM |
2130 | |
2131 | netlink_table_grab(); | |
2132 | ||
2133 | nl_table[NETLINK_USERSOCK].groups = groups; | |
5c398dc8 | 2134 | rcu_assign_pointer(nl_table[NETLINK_USERSOCK].listeners, listeners); |
b963ea89 DM |
2135 | nl_table[NETLINK_USERSOCK].module = THIS_MODULE; |
2136 | nl_table[NETLINK_USERSOCK].registered = 1; | |
9785e10a | 2137 | nl_table[NETLINK_USERSOCK].flags = NL_CFG_F_NONROOT_SEND; |
b963ea89 DM |
2138 | |
2139 | netlink_table_ungrab(); | |
2140 | } | |
2141 | ||
022cbae6 | 2142 | static struct pernet_operations __net_initdata netlink_net_ops = { |
b4b51029 EB |
2143 | .init = netlink_net_init, |
2144 | .exit = netlink_net_exit, | |
2145 | }; | |
2146 | ||
1da177e4 LT |
2147 | static int __init netlink_proto_init(void) |
2148 | { | |
1da177e4 | 2149 | int i; |
26ff5ddc | 2150 | unsigned long limit; |
1da177e4 LT |
2151 | unsigned int order; |
2152 | int err = proto_register(&netlink_proto, 0); | |
2153 | ||
2154 | if (err != 0) | |
2155 | goto out; | |
2156 | ||
fab25745 | 2157 | BUILD_BUG_ON(sizeof(struct netlink_skb_parms) > FIELD_SIZEOF(struct sk_buff, cb)); |
1da177e4 | 2158 | |
0da974f4 | 2159 | nl_table = kcalloc(MAX_LINKS, sizeof(*nl_table), GFP_KERNEL); |
fab2caf6 AM |
2160 | if (!nl_table) |
2161 | goto panic; | |
1da177e4 | 2162 | |
4481374c JB |
2163 | if (totalram_pages >= (128 * 1024)) |
2164 | limit = totalram_pages >> (21 - PAGE_SHIFT); | |
1da177e4 | 2165 | else |
4481374c | 2166 | limit = totalram_pages >> (23 - PAGE_SHIFT); |
1da177e4 | 2167 | |
26ff5ddc DC |
2168 | order = get_bitmask_order(limit) - 1 + PAGE_SHIFT; |
2169 | limit = (1UL << order) / sizeof(struct hlist_head); | |
2170 | order = get_bitmask_order(min(limit, (unsigned long)UINT_MAX)) - 1; | |
1da177e4 LT |
2171 | |
2172 | for (i = 0; i < MAX_LINKS; i++) { | |
15e47304 | 2173 | struct nl_portid_hash *hash = &nl_table[i].hash; |
1da177e4 | 2174 | |
15e47304 | 2175 | hash->table = nl_portid_hash_zalloc(1 * sizeof(*hash->table)); |
1da177e4 LT |
2176 | if (!hash->table) { |
2177 | while (i-- > 0) | |
15e47304 | 2178 | nl_portid_hash_free(nl_table[i].hash.table, |
1da177e4 LT |
2179 | 1 * sizeof(*hash->table)); |
2180 | kfree(nl_table); | |
fab2caf6 | 2181 | goto panic; |
1da177e4 | 2182 | } |
1da177e4 LT |
2183 | hash->max_shift = order; |
2184 | hash->shift = 0; | |
2185 | hash->mask = 0; | |
2186 | hash->rehash_time = jiffies; | |
2187 | } | |
2188 | ||
b963ea89 DM |
2189 | netlink_add_usersock_entry(); |
2190 | ||
1da177e4 | 2191 | sock_register(&netlink_family_ops); |
b4b51029 | 2192 | register_pernet_subsys(&netlink_net_ops); |
746fac4d | 2193 | /* The netlink device handler may be needed early. */ |
1da177e4 LT |
2194 | rtnetlink_init(); |
2195 | out: | |
2196 | return err; | |
fab2caf6 AM |
2197 | panic: |
2198 | panic("netlink_init: Cannot allocate nl_table\n"); | |
1da177e4 LT |
2199 | } |
2200 | ||
1da177e4 | 2201 | core_initcall(netlink_proto_init); |