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