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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 | |
f7fa9b10 | 64 | #define NLGRPSZ(x) (ALIGN(x, sizeof(unsigned long) * 8) / 8) |
b4ff4f04 | 65 | #define NLGRPLONGS(x) (NLGRPSZ(x)/sizeof(unsigned long)) |
1da177e4 LT |
66 | |
67 | struct netlink_sock { | |
68 | /* struct sock has to be the first member of netlink_sock */ | |
69 | struct sock sk; | |
70 | u32 pid; | |
1da177e4 | 71 | u32 dst_pid; |
d629b836 | 72 | u32 dst_group; |
f7fa9b10 PM |
73 | u32 flags; |
74 | u32 subscriptions; | |
75 | u32 ngroups; | |
76 | unsigned long *groups; | |
1da177e4 LT |
77 | unsigned long state; |
78 | wait_queue_head_t wait; | |
79 | struct netlink_callback *cb; | |
af65bdfc PM |
80 | struct mutex *cb_mutex; |
81 | struct mutex cb_def_mutex; | |
cd40b7d3 | 82 | void (*netlink_rcv)(struct sk_buff *skb); |
03292745 | 83 | void (*netlink_bind)(int group); |
77247bbb | 84 | struct module *module; |
1da177e4 LT |
85 | }; |
86 | ||
5c398dc8 ED |
87 | struct listeners { |
88 | struct rcu_head rcu; | |
89 | unsigned long masks[0]; | |
6c04bb18 JB |
90 | }; |
91 | ||
77247bbb | 92 | #define NETLINK_KERNEL_SOCKET 0x1 |
9a4595bc | 93 | #define NETLINK_RECV_PKTINFO 0x2 |
be0c22a4 | 94 | #define NETLINK_BROADCAST_SEND_ERROR 0x4 |
38938bfe | 95 | #define NETLINK_RECV_NO_ENOBUFS 0x8 |
77247bbb | 96 | |
1da177e4 LT |
97 | static inline struct netlink_sock *nlk_sk(struct sock *sk) |
98 | { | |
32b21e03 | 99 | return container_of(sk, struct netlink_sock, sk); |
1da177e4 LT |
100 | } |
101 | ||
035c4c16 | 102 | static inline int netlink_is_kernel(struct sock *sk) |
aed81560 DL |
103 | { |
104 | return nlk_sk(sk)->flags & NETLINK_KERNEL_SOCKET; | |
105 | } | |
106 | ||
1da177e4 | 107 | struct nl_pid_hash { |
658cb354 ED |
108 | struct hlist_head *table; |
109 | unsigned long rehash_time; | |
1da177e4 | 110 | |
658cb354 ED |
111 | unsigned int mask; |
112 | unsigned int shift; | |
1da177e4 | 113 | |
658cb354 ED |
114 | unsigned int entries; |
115 | unsigned int max_shift; | |
1da177e4 | 116 | |
658cb354 | 117 | u32 rnd; |
1da177e4 LT |
118 | }; |
119 | ||
120 | struct netlink_table { | |
658cb354 ED |
121 | struct nl_pid_hash hash; |
122 | struct hlist_head mc_list; | |
123 | struct listeners __rcu *listeners; | |
124 | unsigned int nl_nonroot; | |
125 | unsigned int groups; | |
126 | struct mutex *cb_mutex; | |
127 | struct module *module; | |
03292745 | 128 | void (*bind)(int group); |
658cb354 | 129 | int registered; |
1da177e4 LT |
130 | }; |
131 | ||
132 | static struct netlink_table *nl_table; | |
133 | ||
134 | static DECLARE_WAIT_QUEUE_HEAD(nl_table_wait); | |
135 | ||
136 | static int netlink_dump(struct sock *sk); | |
1da177e4 LT |
137 | |
138 | static DEFINE_RWLOCK(nl_table_lock); | |
139 | static atomic_t nl_table_users = ATOMIC_INIT(0); | |
140 | ||
e041c683 | 141 | static ATOMIC_NOTIFIER_HEAD(netlink_chain); |
1da177e4 | 142 | |
b57ef81f | 143 | static inline u32 netlink_group_mask(u32 group) |
d629b836 PM |
144 | { |
145 | return group ? 1 << (group - 1) : 0; | |
146 | } | |
147 | ||
b57ef81f | 148 | static inline struct hlist_head *nl_pid_hashfn(struct nl_pid_hash *hash, u32 pid) |
1da177e4 LT |
149 | { |
150 | return &hash->table[jhash_1word(pid, hash->rnd) & hash->mask]; | |
151 | } | |
152 | ||
658cb354 ED |
153 | static void netlink_destroy_callback(struct netlink_callback *cb) |
154 | { | |
155 | kfree_skb(cb->skb); | |
156 | kfree(cb); | |
157 | } | |
158 | ||
bfb253c9 ED |
159 | static void netlink_consume_callback(struct netlink_callback *cb) |
160 | { | |
161 | consume_skb(cb->skb); | |
162 | kfree(cb); | |
163 | } | |
164 | ||
1da177e4 LT |
165 | static void netlink_sock_destruct(struct sock *sk) |
166 | { | |
3f660d66 HX |
167 | struct netlink_sock *nlk = nlk_sk(sk); |
168 | ||
3f660d66 HX |
169 | if (nlk->cb) { |
170 | if (nlk->cb->done) | |
171 | nlk->cb->done(nlk->cb); | |
172 | netlink_destroy_callback(nlk->cb); | |
173 | } | |
174 | ||
1da177e4 LT |
175 | skb_queue_purge(&sk->sk_receive_queue); |
176 | ||
177 | if (!sock_flag(sk, SOCK_DEAD)) { | |
6ac552fd | 178 | printk(KERN_ERR "Freeing alive netlink socket %p\n", sk); |
1da177e4 LT |
179 | return; |
180 | } | |
547b792c IJ |
181 | |
182 | WARN_ON(atomic_read(&sk->sk_rmem_alloc)); | |
183 | WARN_ON(atomic_read(&sk->sk_wmem_alloc)); | |
184 | WARN_ON(nlk_sk(sk)->groups); | |
1da177e4 LT |
185 | } |
186 | ||
6ac552fd PM |
187 | /* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on |
188 | * SMP. Look, when several writers sleep and reader wakes them up, all but one | |
1da177e4 LT |
189 | * immediately hit write lock and grab all the cpus. Exclusive sleep solves |
190 | * this, _but_ remember, it adds useless work on UP machines. | |
191 | */ | |
192 | ||
d136f1bd | 193 | void netlink_table_grab(void) |
9a429c49 | 194 | __acquires(nl_table_lock) |
1da177e4 | 195 | { |
d136f1bd JB |
196 | might_sleep(); |
197 | ||
6abd219c | 198 | write_lock_irq(&nl_table_lock); |
1da177e4 LT |
199 | |
200 | if (atomic_read(&nl_table_users)) { | |
201 | DECLARE_WAITQUEUE(wait, current); | |
202 | ||
203 | add_wait_queue_exclusive(&nl_table_wait, &wait); | |
6ac552fd | 204 | for (;;) { |
1da177e4 LT |
205 | set_current_state(TASK_UNINTERRUPTIBLE); |
206 | if (atomic_read(&nl_table_users) == 0) | |
207 | break; | |
6abd219c | 208 | write_unlock_irq(&nl_table_lock); |
1da177e4 | 209 | schedule(); |
6abd219c | 210 | write_lock_irq(&nl_table_lock); |
1da177e4 LT |
211 | } |
212 | ||
213 | __set_current_state(TASK_RUNNING); | |
214 | remove_wait_queue(&nl_table_wait, &wait); | |
215 | } | |
216 | } | |
217 | ||
d136f1bd | 218 | void netlink_table_ungrab(void) |
9a429c49 | 219 | __releases(nl_table_lock) |
1da177e4 | 220 | { |
6abd219c | 221 | write_unlock_irq(&nl_table_lock); |
1da177e4 LT |
222 | wake_up(&nl_table_wait); |
223 | } | |
224 | ||
6ac552fd | 225 | static inline void |
1da177e4 LT |
226 | netlink_lock_table(void) |
227 | { | |
228 | /* read_lock() synchronizes us to netlink_table_grab */ | |
229 | ||
230 | read_lock(&nl_table_lock); | |
231 | atomic_inc(&nl_table_users); | |
232 | read_unlock(&nl_table_lock); | |
233 | } | |
234 | ||
6ac552fd | 235 | static inline void |
1da177e4 LT |
236 | netlink_unlock_table(void) |
237 | { | |
238 | if (atomic_dec_and_test(&nl_table_users)) | |
239 | wake_up(&nl_table_wait); | |
240 | } | |
241 | ||
b57ef81f | 242 | static struct sock *netlink_lookup(struct net *net, int protocol, u32 pid) |
1da177e4 LT |
243 | { |
244 | struct nl_pid_hash *hash = &nl_table[protocol].hash; | |
245 | struct hlist_head *head; | |
246 | struct sock *sk; | |
247 | struct hlist_node *node; | |
248 | ||
249 | read_lock(&nl_table_lock); | |
250 | head = nl_pid_hashfn(hash, pid); | |
251 | sk_for_each(sk, node, head) { | |
878628fb | 252 | if (net_eq(sock_net(sk), net) && (nlk_sk(sk)->pid == pid)) { |
1da177e4 LT |
253 | sock_hold(sk); |
254 | goto found; | |
255 | } | |
256 | } | |
257 | sk = NULL; | |
258 | found: | |
259 | read_unlock(&nl_table_lock); | |
260 | return sk; | |
261 | } | |
262 | ||
b57ef81f | 263 | static struct hlist_head *nl_pid_hash_zalloc(size_t size) |
1da177e4 LT |
264 | { |
265 | if (size <= PAGE_SIZE) | |
ea72912c | 266 | return kzalloc(size, GFP_ATOMIC); |
1da177e4 LT |
267 | else |
268 | return (struct hlist_head *) | |
ea72912c ED |
269 | __get_free_pages(GFP_ATOMIC | __GFP_ZERO, |
270 | get_order(size)); | |
1da177e4 LT |
271 | } |
272 | ||
b57ef81f | 273 | static void nl_pid_hash_free(struct hlist_head *table, size_t size) |
1da177e4 LT |
274 | { |
275 | if (size <= PAGE_SIZE) | |
276 | kfree(table); | |
277 | else | |
278 | free_pages((unsigned long)table, get_order(size)); | |
279 | } | |
280 | ||
281 | static int nl_pid_hash_rehash(struct nl_pid_hash *hash, int grow) | |
282 | { | |
283 | unsigned int omask, mask, shift; | |
284 | size_t osize, size; | |
285 | struct hlist_head *otable, *table; | |
286 | int i; | |
287 | ||
288 | omask = mask = hash->mask; | |
289 | osize = size = (mask + 1) * sizeof(*table); | |
290 | shift = hash->shift; | |
291 | ||
292 | if (grow) { | |
293 | if (++shift > hash->max_shift) | |
294 | return 0; | |
295 | mask = mask * 2 + 1; | |
296 | size *= 2; | |
297 | } | |
298 | ||
ea72912c | 299 | table = nl_pid_hash_zalloc(size); |
1da177e4 LT |
300 | if (!table) |
301 | return 0; | |
302 | ||
1da177e4 LT |
303 | otable = hash->table; |
304 | hash->table = table; | |
305 | hash->mask = mask; | |
306 | hash->shift = shift; | |
307 | get_random_bytes(&hash->rnd, sizeof(hash->rnd)); | |
308 | ||
309 | for (i = 0; i <= omask; i++) { | |
310 | struct sock *sk; | |
311 | struct hlist_node *node, *tmp; | |
312 | ||
313 | sk_for_each_safe(sk, node, tmp, &otable[i]) | |
314 | __sk_add_node(sk, nl_pid_hashfn(hash, nlk_sk(sk)->pid)); | |
315 | } | |
316 | ||
317 | nl_pid_hash_free(otable, osize); | |
318 | hash->rehash_time = jiffies + 10 * 60 * HZ; | |
319 | return 1; | |
320 | } | |
321 | ||
322 | static inline int nl_pid_hash_dilute(struct nl_pid_hash *hash, int len) | |
323 | { | |
324 | int avg = hash->entries >> hash->shift; | |
325 | ||
326 | if (unlikely(avg > 1) && nl_pid_hash_rehash(hash, 1)) | |
327 | return 1; | |
328 | ||
329 | if (unlikely(len > avg) && time_after(jiffies, hash->rehash_time)) { | |
330 | nl_pid_hash_rehash(hash, 0); | |
331 | return 1; | |
332 | } | |
333 | ||
334 | return 0; | |
335 | } | |
336 | ||
90ddc4f0 | 337 | static const struct proto_ops netlink_ops; |
1da177e4 | 338 | |
4277a083 PM |
339 | static void |
340 | netlink_update_listeners(struct sock *sk) | |
341 | { | |
342 | struct netlink_table *tbl = &nl_table[sk->sk_protocol]; | |
343 | struct hlist_node *node; | |
344 | unsigned long mask; | |
345 | unsigned int i; | |
346 | ||
b4ff4f04 | 347 | for (i = 0; i < NLGRPLONGS(tbl->groups); i++) { |
4277a083 | 348 | mask = 0; |
b4ff4f04 JB |
349 | sk_for_each_bound(sk, node, &tbl->mc_list) { |
350 | if (i < NLGRPLONGS(nlk_sk(sk)->ngroups)) | |
351 | mask |= nlk_sk(sk)->groups[i]; | |
352 | } | |
5c398dc8 | 353 | tbl->listeners->masks[i] = mask; |
4277a083 PM |
354 | } |
355 | /* this function is only called with the netlink table "grabbed", which | |
356 | * makes sure updates are visible before bind or setsockopt return. */ | |
357 | } | |
358 | ||
b4b51029 | 359 | static int netlink_insert(struct sock *sk, struct net *net, u32 pid) |
1da177e4 LT |
360 | { |
361 | struct nl_pid_hash *hash = &nl_table[sk->sk_protocol].hash; | |
362 | struct hlist_head *head; | |
363 | int err = -EADDRINUSE; | |
364 | struct sock *osk; | |
365 | struct hlist_node *node; | |
366 | int len; | |
367 | ||
368 | netlink_table_grab(); | |
369 | head = nl_pid_hashfn(hash, pid); | |
370 | len = 0; | |
371 | sk_for_each(osk, node, head) { | |
878628fb | 372 | if (net_eq(sock_net(osk), net) && (nlk_sk(osk)->pid == pid)) |
1da177e4 LT |
373 | break; |
374 | len++; | |
375 | } | |
376 | if (node) | |
377 | goto err; | |
378 | ||
379 | err = -EBUSY; | |
380 | if (nlk_sk(sk)->pid) | |
381 | goto err; | |
382 | ||
383 | err = -ENOMEM; | |
384 | if (BITS_PER_LONG > 32 && unlikely(hash->entries >= UINT_MAX)) | |
385 | goto err; | |
386 | ||
387 | if (len && nl_pid_hash_dilute(hash, len)) | |
388 | head = nl_pid_hashfn(hash, pid); | |
389 | hash->entries++; | |
390 | nlk_sk(sk)->pid = pid; | |
391 | sk_add_node(sk, head); | |
392 | err = 0; | |
393 | ||
394 | err: | |
395 | netlink_table_ungrab(); | |
396 | return err; | |
397 | } | |
398 | ||
399 | static void netlink_remove(struct sock *sk) | |
400 | { | |
401 | netlink_table_grab(); | |
d470e3b4 DM |
402 | if (sk_del_node_init(sk)) |
403 | nl_table[sk->sk_protocol].hash.entries--; | |
f7fa9b10 | 404 | if (nlk_sk(sk)->subscriptions) |
1da177e4 LT |
405 | __sk_del_bind_node(sk); |
406 | netlink_table_ungrab(); | |
407 | } | |
408 | ||
409 | static struct proto netlink_proto = { | |
410 | .name = "NETLINK", | |
411 | .owner = THIS_MODULE, | |
412 | .obj_size = sizeof(struct netlink_sock), | |
413 | }; | |
414 | ||
1b8d7ae4 EB |
415 | static int __netlink_create(struct net *net, struct socket *sock, |
416 | struct mutex *cb_mutex, int protocol) | |
1da177e4 LT |
417 | { |
418 | struct sock *sk; | |
419 | struct netlink_sock *nlk; | |
ab33a171 PM |
420 | |
421 | sock->ops = &netlink_ops; | |
422 | ||
6257ff21 | 423 | sk = sk_alloc(net, PF_NETLINK, GFP_KERNEL, &netlink_proto); |
ab33a171 PM |
424 | if (!sk) |
425 | return -ENOMEM; | |
426 | ||
427 | sock_init_data(sock, sk); | |
428 | ||
429 | nlk = nlk_sk(sk); | |
658cb354 | 430 | if (cb_mutex) { |
ffa4d721 | 431 | nlk->cb_mutex = cb_mutex; |
658cb354 | 432 | } else { |
ffa4d721 PM |
433 | nlk->cb_mutex = &nlk->cb_def_mutex; |
434 | mutex_init(nlk->cb_mutex); | |
435 | } | |
ab33a171 PM |
436 | init_waitqueue_head(&nlk->wait); |
437 | ||
438 | sk->sk_destruct = netlink_sock_destruct; | |
439 | sk->sk_protocol = protocol; | |
440 | return 0; | |
441 | } | |
442 | ||
3f378b68 EP |
443 | static int netlink_create(struct net *net, struct socket *sock, int protocol, |
444 | int kern) | |
ab33a171 PM |
445 | { |
446 | struct module *module = NULL; | |
af65bdfc | 447 | struct mutex *cb_mutex; |
f7fa9b10 | 448 | struct netlink_sock *nlk; |
03292745 | 449 | void (*bind)(int group); |
ab33a171 | 450 | int err = 0; |
1da177e4 LT |
451 | |
452 | sock->state = SS_UNCONNECTED; | |
453 | ||
454 | if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM) | |
455 | return -ESOCKTNOSUPPORT; | |
456 | ||
6ac552fd | 457 | if (protocol < 0 || protocol >= MAX_LINKS) |
1da177e4 LT |
458 | return -EPROTONOSUPPORT; |
459 | ||
77247bbb | 460 | netlink_lock_table(); |
95a5afca | 461 | #ifdef CONFIG_MODULES |
ab33a171 | 462 | if (!nl_table[protocol].registered) { |
77247bbb | 463 | netlink_unlock_table(); |
4fdb3bb7 | 464 | request_module("net-pf-%d-proto-%d", PF_NETLINK, protocol); |
77247bbb | 465 | netlink_lock_table(); |
4fdb3bb7 | 466 | } |
ab33a171 PM |
467 | #endif |
468 | if (nl_table[protocol].registered && | |
469 | try_module_get(nl_table[protocol].module)) | |
470 | module = nl_table[protocol].module; | |
974c37e9 AD |
471 | else |
472 | err = -EPROTONOSUPPORT; | |
af65bdfc | 473 | cb_mutex = nl_table[protocol].cb_mutex; |
03292745 | 474 | bind = nl_table[protocol].bind; |
77247bbb | 475 | netlink_unlock_table(); |
4fdb3bb7 | 476 | |
974c37e9 AD |
477 | if (err < 0) |
478 | goto out; | |
479 | ||
6ac552fd PM |
480 | err = __netlink_create(net, sock, cb_mutex, protocol); |
481 | if (err < 0) | |
f7fa9b10 PM |
482 | goto out_module; |
483 | ||
6f756a8c | 484 | local_bh_disable(); |
c1fd3b94 | 485 | sock_prot_inuse_add(net, &netlink_proto, 1); |
6f756a8c DM |
486 | local_bh_enable(); |
487 | ||
f7fa9b10 | 488 | nlk = nlk_sk(sock->sk); |
f7fa9b10 | 489 | nlk->module = module; |
03292745 | 490 | nlk->netlink_bind = bind; |
ab33a171 PM |
491 | out: |
492 | return err; | |
1da177e4 | 493 | |
ab33a171 PM |
494 | out_module: |
495 | module_put(module); | |
496 | goto out; | |
1da177e4 LT |
497 | } |
498 | ||
499 | static int netlink_release(struct socket *sock) | |
500 | { | |
501 | struct sock *sk = sock->sk; | |
502 | struct netlink_sock *nlk; | |
503 | ||
504 | if (!sk) | |
505 | return 0; | |
506 | ||
507 | netlink_remove(sk); | |
ac57b3a9 | 508 | sock_orphan(sk); |
1da177e4 LT |
509 | nlk = nlk_sk(sk); |
510 | ||
3f660d66 HX |
511 | /* |
512 | * OK. Socket is unlinked, any packets that arrive now | |
513 | * will be purged. | |
514 | */ | |
1da177e4 | 515 | |
1da177e4 LT |
516 | sock->sk = NULL; |
517 | wake_up_interruptible_all(&nlk->wait); | |
518 | ||
519 | skb_queue_purge(&sk->sk_write_queue); | |
520 | ||
649300b9 | 521 | if (nlk->pid) { |
1da177e4 | 522 | struct netlink_notify n = { |
3b1e0a65 | 523 | .net = sock_net(sk), |
1da177e4 LT |
524 | .protocol = sk->sk_protocol, |
525 | .pid = nlk->pid, | |
526 | }; | |
e041c683 AS |
527 | atomic_notifier_call_chain(&netlink_chain, |
528 | NETLINK_URELEASE, &n); | |
746fac4d | 529 | } |
4fdb3bb7 | 530 | |
5e7c001c | 531 | module_put(nlk->module); |
4fdb3bb7 | 532 | |
4277a083 | 533 | netlink_table_grab(); |
aed81560 | 534 | if (netlink_is_kernel(sk)) { |
869e58f8 DL |
535 | BUG_ON(nl_table[sk->sk_protocol].registered == 0); |
536 | if (--nl_table[sk->sk_protocol].registered == 0) { | |
537 | kfree(nl_table[sk->sk_protocol].listeners); | |
538 | nl_table[sk->sk_protocol].module = NULL; | |
539 | nl_table[sk->sk_protocol].registered = 0; | |
540 | } | |
658cb354 | 541 | } else if (nlk->subscriptions) { |
4277a083 | 542 | netlink_update_listeners(sk); |
658cb354 | 543 | } |
4277a083 | 544 | netlink_table_ungrab(); |
77247bbb | 545 | |
f7fa9b10 PM |
546 | kfree(nlk->groups); |
547 | nlk->groups = NULL; | |
548 | ||
3755810c | 549 | local_bh_disable(); |
c1fd3b94 | 550 | sock_prot_inuse_add(sock_net(sk), &netlink_proto, -1); |
3755810c | 551 | local_bh_enable(); |
1da177e4 LT |
552 | sock_put(sk); |
553 | return 0; | |
554 | } | |
555 | ||
556 | static int netlink_autobind(struct socket *sock) | |
557 | { | |
558 | struct sock *sk = sock->sk; | |
3b1e0a65 | 559 | struct net *net = sock_net(sk); |
1da177e4 LT |
560 | struct nl_pid_hash *hash = &nl_table[sk->sk_protocol].hash; |
561 | struct hlist_head *head; | |
562 | struct sock *osk; | |
563 | struct hlist_node *node; | |
66aa4a55 | 564 | s32 pid = task_tgid_vnr(current); |
1da177e4 LT |
565 | int err; |
566 | static s32 rover = -4097; | |
567 | ||
568 | retry: | |
569 | cond_resched(); | |
570 | netlink_table_grab(); | |
571 | head = nl_pid_hashfn(hash, pid); | |
572 | sk_for_each(osk, node, head) { | |
878628fb | 573 | if (!net_eq(sock_net(osk), net)) |
b4b51029 | 574 | continue; |
1da177e4 LT |
575 | if (nlk_sk(osk)->pid == pid) { |
576 | /* Bind collision, search negative pid values. */ | |
577 | pid = rover--; | |
578 | if (rover > -4097) | |
579 | rover = -4097; | |
580 | netlink_table_ungrab(); | |
581 | goto retry; | |
582 | } | |
583 | } | |
584 | netlink_table_ungrab(); | |
585 | ||
b4b51029 | 586 | err = netlink_insert(sk, net, pid); |
1da177e4 LT |
587 | if (err == -EADDRINUSE) |
588 | goto retry; | |
d470e3b4 DM |
589 | |
590 | /* If 2 threads race to autobind, that is fine. */ | |
591 | if (err == -EBUSY) | |
592 | err = 0; | |
593 | ||
594 | return err; | |
1da177e4 LT |
595 | } |
596 | ||
b57ef81f | 597 | static inline int netlink_capable(const struct socket *sock, unsigned int flag) |
746fac4d | 598 | { |
1da177e4 LT |
599 | return (nl_table[sock->sk->sk_protocol].nl_nonroot & flag) || |
600 | capable(CAP_NET_ADMIN); | |
746fac4d | 601 | } |
1da177e4 | 602 | |
f7fa9b10 PM |
603 | static void |
604 | netlink_update_subscriptions(struct sock *sk, unsigned int subscriptions) | |
605 | { | |
606 | struct netlink_sock *nlk = nlk_sk(sk); | |
607 | ||
608 | if (nlk->subscriptions && !subscriptions) | |
609 | __sk_del_bind_node(sk); | |
610 | else if (!nlk->subscriptions && subscriptions) | |
611 | sk_add_bind_node(sk, &nl_table[sk->sk_protocol].mc_list); | |
612 | nlk->subscriptions = subscriptions; | |
613 | } | |
614 | ||
b4ff4f04 | 615 | static int netlink_realloc_groups(struct sock *sk) |
513c2500 PM |
616 | { |
617 | struct netlink_sock *nlk = nlk_sk(sk); | |
618 | unsigned int groups; | |
b4ff4f04 | 619 | unsigned long *new_groups; |
513c2500 PM |
620 | int err = 0; |
621 | ||
b4ff4f04 JB |
622 | netlink_table_grab(); |
623 | ||
513c2500 | 624 | groups = nl_table[sk->sk_protocol].groups; |
b4ff4f04 | 625 | if (!nl_table[sk->sk_protocol].registered) { |
513c2500 | 626 | err = -ENOENT; |
b4ff4f04 JB |
627 | goto out_unlock; |
628 | } | |
513c2500 | 629 | |
b4ff4f04 JB |
630 | if (nlk->ngroups >= groups) |
631 | goto out_unlock; | |
513c2500 | 632 | |
b4ff4f04 JB |
633 | new_groups = krealloc(nlk->groups, NLGRPSZ(groups), GFP_ATOMIC); |
634 | if (new_groups == NULL) { | |
635 | err = -ENOMEM; | |
636 | goto out_unlock; | |
637 | } | |
6ac552fd | 638 | memset((char *)new_groups + NLGRPSZ(nlk->ngroups), 0, |
b4ff4f04 JB |
639 | NLGRPSZ(groups) - NLGRPSZ(nlk->ngroups)); |
640 | ||
641 | nlk->groups = new_groups; | |
513c2500 | 642 | nlk->ngroups = groups; |
b4ff4f04 JB |
643 | out_unlock: |
644 | netlink_table_ungrab(); | |
645 | return err; | |
513c2500 PM |
646 | } |
647 | ||
6ac552fd PM |
648 | static int netlink_bind(struct socket *sock, struct sockaddr *addr, |
649 | int addr_len) | |
1da177e4 LT |
650 | { |
651 | struct sock *sk = sock->sk; | |
3b1e0a65 | 652 | struct net *net = sock_net(sk); |
1da177e4 LT |
653 | struct netlink_sock *nlk = nlk_sk(sk); |
654 | struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr; | |
655 | int err; | |
746fac4d | 656 | |
1da177e4 LT |
657 | if (nladdr->nl_family != AF_NETLINK) |
658 | return -EINVAL; | |
659 | ||
660 | /* Only superuser is allowed to listen multicasts */ | |
513c2500 PM |
661 | if (nladdr->nl_groups) { |
662 | if (!netlink_capable(sock, NL_NONROOT_RECV)) | |
663 | return -EPERM; | |
b4ff4f04 JB |
664 | err = netlink_realloc_groups(sk); |
665 | if (err) | |
666 | return err; | |
513c2500 | 667 | } |
1da177e4 LT |
668 | |
669 | if (nlk->pid) { | |
670 | if (nladdr->nl_pid != nlk->pid) | |
671 | return -EINVAL; | |
672 | } else { | |
673 | err = nladdr->nl_pid ? | |
b4b51029 | 674 | netlink_insert(sk, net, nladdr->nl_pid) : |
1da177e4 LT |
675 | netlink_autobind(sock); |
676 | if (err) | |
677 | return err; | |
678 | } | |
679 | ||
513c2500 | 680 | if (!nladdr->nl_groups && (nlk->groups == NULL || !(u32)nlk->groups[0])) |
1da177e4 LT |
681 | return 0; |
682 | ||
683 | netlink_table_grab(); | |
f7fa9b10 | 684 | netlink_update_subscriptions(sk, nlk->subscriptions + |
746fac4d YH |
685 | hweight32(nladdr->nl_groups) - |
686 | hweight32(nlk->groups[0])); | |
687 | nlk->groups[0] = (nlk->groups[0] & ~0xffffffffUL) | nladdr->nl_groups; | |
4277a083 | 688 | netlink_update_listeners(sk); |
1da177e4 LT |
689 | netlink_table_ungrab(); |
690 | ||
03292745 PNA |
691 | if (nlk->netlink_bind && nlk->groups[0]) { |
692 | int i; | |
693 | ||
694 | for (i=0; i<nlk->ngroups; i++) { | |
695 | if (test_bit(i, nlk->groups)) | |
696 | nlk->netlink_bind(i); | |
697 | } | |
698 | } | |
699 | ||
1da177e4 LT |
700 | return 0; |
701 | } | |
702 | ||
703 | static int netlink_connect(struct socket *sock, struct sockaddr *addr, | |
704 | int alen, int flags) | |
705 | { | |
706 | int err = 0; | |
707 | struct sock *sk = sock->sk; | |
708 | struct netlink_sock *nlk = nlk_sk(sk); | |
6ac552fd | 709 | struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr; |
1da177e4 | 710 | |
6503d961 CG |
711 | if (alen < sizeof(addr->sa_family)) |
712 | return -EINVAL; | |
713 | ||
1da177e4 LT |
714 | if (addr->sa_family == AF_UNSPEC) { |
715 | sk->sk_state = NETLINK_UNCONNECTED; | |
716 | nlk->dst_pid = 0; | |
d629b836 | 717 | nlk->dst_group = 0; |
1da177e4 LT |
718 | return 0; |
719 | } | |
720 | if (addr->sa_family != AF_NETLINK) | |
721 | return -EINVAL; | |
722 | ||
723 | /* Only superuser is allowed to send multicasts */ | |
724 | if (nladdr->nl_groups && !netlink_capable(sock, NL_NONROOT_SEND)) | |
725 | return -EPERM; | |
726 | ||
727 | if (!nlk->pid) | |
728 | err = netlink_autobind(sock); | |
729 | ||
730 | if (err == 0) { | |
731 | sk->sk_state = NETLINK_CONNECTED; | |
732 | nlk->dst_pid = nladdr->nl_pid; | |
d629b836 | 733 | nlk->dst_group = ffs(nladdr->nl_groups); |
1da177e4 LT |
734 | } |
735 | ||
736 | return err; | |
737 | } | |
738 | ||
6ac552fd PM |
739 | static int netlink_getname(struct socket *sock, struct sockaddr *addr, |
740 | int *addr_len, int peer) | |
1da177e4 LT |
741 | { |
742 | struct sock *sk = sock->sk; | |
743 | struct netlink_sock *nlk = nlk_sk(sk); | |
13cfa97b | 744 | DECLARE_SOCKADDR(struct sockaddr_nl *, nladdr, addr); |
746fac4d | 745 | |
1da177e4 LT |
746 | nladdr->nl_family = AF_NETLINK; |
747 | nladdr->nl_pad = 0; | |
748 | *addr_len = sizeof(*nladdr); | |
749 | ||
750 | if (peer) { | |
751 | nladdr->nl_pid = nlk->dst_pid; | |
d629b836 | 752 | nladdr->nl_groups = netlink_group_mask(nlk->dst_group); |
1da177e4 LT |
753 | } else { |
754 | nladdr->nl_pid = nlk->pid; | |
513c2500 | 755 | nladdr->nl_groups = nlk->groups ? nlk->groups[0] : 0; |
1da177e4 LT |
756 | } |
757 | return 0; | |
758 | } | |
759 | ||
760 | static void netlink_overrun(struct sock *sk) | |
761 | { | |
38938bfe PNA |
762 | struct netlink_sock *nlk = nlk_sk(sk); |
763 | ||
764 | if (!(nlk->flags & NETLINK_RECV_NO_ENOBUFS)) { | |
765 | if (!test_and_set_bit(0, &nlk_sk(sk)->state)) { | |
766 | sk->sk_err = ENOBUFS; | |
767 | sk->sk_error_report(sk); | |
768 | } | |
1da177e4 | 769 | } |
38938bfe | 770 | atomic_inc(&sk->sk_drops); |
1da177e4 LT |
771 | } |
772 | ||
773 | static struct sock *netlink_getsockbypid(struct sock *ssk, u32 pid) | |
774 | { | |
1da177e4 LT |
775 | struct sock *sock; |
776 | struct netlink_sock *nlk; | |
777 | ||
3b1e0a65 | 778 | sock = netlink_lookup(sock_net(ssk), ssk->sk_protocol, pid); |
1da177e4 LT |
779 | if (!sock) |
780 | return ERR_PTR(-ECONNREFUSED); | |
781 | ||
782 | /* Don't bother queuing skb if kernel socket has no input function */ | |
783 | nlk = nlk_sk(sock); | |
cd40b7d3 DL |
784 | if (sock->sk_state == NETLINK_CONNECTED && |
785 | nlk->dst_pid != nlk_sk(ssk)->pid) { | |
1da177e4 LT |
786 | sock_put(sock); |
787 | return ERR_PTR(-ECONNREFUSED); | |
788 | } | |
789 | return sock; | |
790 | } | |
791 | ||
792 | struct sock *netlink_getsockbyfilp(struct file *filp) | |
793 | { | |
6db5fc5d | 794 | struct inode *inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
795 | struct sock *sock; |
796 | ||
797 | if (!S_ISSOCK(inode->i_mode)) | |
798 | return ERR_PTR(-ENOTSOCK); | |
799 | ||
800 | sock = SOCKET_I(inode)->sk; | |
801 | if (sock->sk_family != AF_NETLINK) | |
802 | return ERR_PTR(-EINVAL); | |
803 | ||
804 | sock_hold(sock); | |
805 | return sock; | |
806 | } | |
807 | ||
808 | /* | |
809 | * Attach a skb to a netlink socket. | |
810 | * The caller must hold a reference to the destination socket. On error, the | |
811 | * reference is dropped. The skb is not send to the destination, just all | |
812 | * all error checks are performed and memory in the queue is reserved. | |
813 | * Return values: | |
814 | * < 0: error. skb freed, reference to sock dropped. | |
815 | * 0: continue | |
816 | * 1: repeat lookup - reference dropped while waiting for socket memory. | |
817 | */ | |
9457afee | 818 | int netlink_attachskb(struct sock *sk, struct sk_buff *skb, |
c3d8d1e3 | 819 | long *timeo, struct sock *ssk) |
1da177e4 LT |
820 | { |
821 | struct netlink_sock *nlk; | |
822 | ||
823 | nlk = nlk_sk(sk); | |
824 | ||
825 | if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || | |
826 | test_bit(0, &nlk->state)) { | |
827 | DECLARE_WAITQUEUE(wait, current); | |
c3d8d1e3 | 828 | if (!*timeo) { |
aed81560 | 829 | if (!ssk || netlink_is_kernel(ssk)) |
1da177e4 LT |
830 | netlink_overrun(sk); |
831 | sock_put(sk); | |
832 | kfree_skb(skb); | |
833 | return -EAGAIN; | |
834 | } | |
835 | ||
836 | __set_current_state(TASK_INTERRUPTIBLE); | |
837 | add_wait_queue(&nlk->wait, &wait); | |
838 | ||
839 | if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || | |
840 | test_bit(0, &nlk->state)) && | |
841 | !sock_flag(sk, SOCK_DEAD)) | |
c3d8d1e3 | 842 | *timeo = schedule_timeout(*timeo); |
1da177e4 LT |
843 | |
844 | __set_current_state(TASK_RUNNING); | |
845 | remove_wait_queue(&nlk->wait, &wait); | |
846 | sock_put(sk); | |
847 | ||
848 | if (signal_pending(current)) { | |
849 | kfree_skb(skb); | |
c3d8d1e3 | 850 | return sock_intr_errno(*timeo); |
1da177e4 LT |
851 | } |
852 | return 1; | |
853 | } | |
854 | skb_set_owner_r(skb, sk); | |
855 | return 0; | |
856 | } | |
857 | ||
4a7e7c2a | 858 | static int __netlink_sendskb(struct sock *sk, struct sk_buff *skb) |
1da177e4 | 859 | { |
1da177e4 LT |
860 | int len = skb->len; |
861 | ||
1da177e4 LT |
862 | skb_queue_tail(&sk->sk_receive_queue, skb); |
863 | sk->sk_data_ready(sk, len); | |
4a7e7c2a ED |
864 | return len; |
865 | } | |
866 | ||
867 | int netlink_sendskb(struct sock *sk, struct sk_buff *skb) | |
868 | { | |
869 | int len = __netlink_sendskb(sk, skb); | |
870 | ||
1da177e4 LT |
871 | sock_put(sk); |
872 | return len; | |
873 | } | |
874 | ||
875 | void netlink_detachskb(struct sock *sk, struct sk_buff *skb) | |
876 | { | |
877 | kfree_skb(skb); | |
878 | sock_put(sk); | |
879 | } | |
880 | ||
b57ef81f | 881 | static struct sk_buff *netlink_trim(struct sk_buff *skb, gfp_t allocation) |
1da177e4 LT |
882 | { |
883 | int delta; | |
884 | ||
885 | skb_orphan(skb); | |
886 | ||
4305b541 | 887 | delta = skb->end - skb->tail; |
1da177e4 LT |
888 | if (delta * 2 < skb->truesize) |
889 | return skb; | |
890 | ||
891 | if (skb_shared(skb)) { | |
892 | struct sk_buff *nskb = skb_clone(skb, allocation); | |
893 | if (!nskb) | |
894 | return skb; | |
8460c00f | 895 | consume_skb(skb); |
1da177e4 LT |
896 | skb = nskb; |
897 | } | |
898 | ||
899 | if (!pskb_expand_head(skb, 0, -delta, allocation)) | |
900 | skb->truesize -= delta; | |
901 | ||
902 | return skb; | |
903 | } | |
904 | ||
b57ef81f | 905 | static void netlink_rcv_wake(struct sock *sk) |
cd40b7d3 DL |
906 | { |
907 | struct netlink_sock *nlk = nlk_sk(sk); | |
908 | ||
909 | if (skb_queue_empty(&sk->sk_receive_queue)) | |
910 | clear_bit(0, &nlk->state); | |
911 | if (!test_bit(0, &nlk->state)) | |
912 | wake_up_interruptible(&nlk->wait); | |
913 | } | |
914 | ||
b57ef81f | 915 | static int netlink_unicast_kernel(struct sock *sk, struct sk_buff *skb) |
cd40b7d3 DL |
916 | { |
917 | int ret; | |
918 | struct netlink_sock *nlk = nlk_sk(sk); | |
919 | ||
920 | ret = -ECONNREFUSED; | |
921 | if (nlk->netlink_rcv != NULL) { | |
922 | ret = skb->len; | |
923 | skb_set_owner_r(skb, sk); | |
924 | nlk->netlink_rcv(skb); | |
bfb253c9 ED |
925 | consume_skb(skb); |
926 | } else { | |
927 | kfree_skb(skb); | |
cd40b7d3 | 928 | } |
cd40b7d3 DL |
929 | sock_put(sk); |
930 | return ret; | |
931 | } | |
932 | ||
933 | int netlink_unicast(struct sock *ssk, struct sk_buff *skb, | |
934 | u32 pid, int nonblock) | |
1da177e4 LT |
935 | { |
936 | struct sock *sk; | |
937 | int err; | |
938 | long timeo; | |
939 | ||
940 | skb = netlink_trim(skb, gfp_any()); | |
941 | ||
942 | timeo = sock_sndtimeo(ssk, nonblock); | |
943 | retry: | |
944 | sk = netlink_getsockbypid(ssk, pid); | |
945 | if (IS_ERR(sk)) { | |
946 | kfree_skb(skb); | |
947 | return PTR_ERR(sk); | |
948 | } | |
cd40b7d3 DL |
949 | if (netlink_is_kernel(sk)) |
950 | return netlink_unicast_kernel(sk, skb); | |
951 | ||
b1153f29 | 952 | if (sk_filter(sk, skb)) { |
84874607 | 953 | err = skb->len; |
b1153f29 SH |
954 | kfree_skb(skb); |
955 | sock_put(sk); | |
956 | return err; | |
957 | } | |
958 | ||
9457afee | 959 | err = netlink_attachskb(sk, skb, &timeo, ssk); |
1da177e4 LT |
960 | if (err == 1) |
961 | goto retry; | |
962 | if (err) | |
963 | return err; | |
964 | ||
7ee015e0 | 965 | return netlink_sendskb(sk, skb); |
1da177e4 | 966 | } |
6ac552fd | 967 | EXPORT_SYMBOL(netlink_unicast); |
1da177e4 | 968 | |
4277a083 PM |
969 | int netlink_has_listeners(struct sock *sk, unsigned int group) |
970 | { | |
971 | int res = 0; | |
5c398dc8 | 972 | struct listeners *listeners; |
4277a083 | 973 | |
aed81560 | 974 | BUG_ON(!netlink_is_kernel(sk)); |
b4ff4f04 JB |
975 | |
976 | rcu_read_lock(); | |
977 | listeners = rcu_dereference(nl_table[sk->sk_protocol].listeners); | |
978 | ||
4277a083 | 979 | if (group - 1 < nl_table[sk->sk_protocol].groups) |
5c398dc8 | 980 | res = test_bit(group - 1, listeners->masks); |
b4ff4f04 JB |
981 | |
982 | rcu_read_unlock(); | |
983 | ||
4277a083 PM |
984 | return res; |
985 | } | |
986 | EXPORT_SYMBOL_GPL(netlink_has_listeners); | |
987 | ||
b57ef81f | 988 | static int netlink_broadcast_deliver(struct sock *sk, struct sk_buff *skb) |
1da177e4 LT |
989 | { |
990 | struct netlink_sock *nlk = nlk_sk(sk); | |
991 | ||
992 | if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf && | |
993 | !test_bit(0, &nlk->state)) { | |
994 | skb_set_owner_r(skb, sk); | |
4a7e7c2a | 995 | __netlink_sendskb(sk, skb); |
2c645800 | 996 | return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1); |
1da177e4 LT |
997 | } |
998 | return -1; | |
999 | } | |
1000 | ||
1001 | struct netlink_broadcast_data { | |
1002 | struct sock *exclude_sk; | |
b4b51029 | 1003 | struct net *net; |
1da177e4 LT |
1004 | u32 pid; |
1005 | u32 group; | |
1006 | int failure; | |
ff491a73 | 1007 | int delivery_failure; |
1da177e4 LT |
1008 | int congested; |
1009 | int delivered; | |
7d877f3b | 1010 | gfp_t allocation; |
1da177e4 | 1011 | struct sk_buff *skb, *skb2; |
910a7e90 EB |
1012 | int (*tx_filter)(struct sock *dsk, struct sk_buff *skb, void *data); |
1013 | void *tx_data; | |
1da177e4 LT |
1014 | }; |
1015 | ||
b57ef81f | 1016 | static int do_one_broadcast(struct sock *sk, |
1da177e4 LT |
1017 | struct netlink_broadcast_data *p) |
1018 | { | |
1019 | struct netlink_sock *nlk = nlk_sk(sk); | |
1020 | int val; | |
1021 | ||
1022 | if (p->exclude_sk == sk) | |
1023 | goto out; | |
1024 | ||
f7fa9b10 PM |
1025 | if (nlk->pid == p->pid || p->group - 1 >= nlk->ngroups || |
1026 | !test_bit(p->group - 1, nlk->groups)) | |
1da177e4 LT |
1027 | goto out; |
1028 | ||
878628fb | 1029 | if (!net_eq(sock_net(sk), p->net)) |
b4b51029 EB |
1030 | goto out; |
1031 | ||
1da177e4 LT |
1032 | if (p->failure) { |
1033 | netlink_overrun(sk); | |
1034 | goto out; | |
1035 | } | |
1036 | ||
1037 | sock_hold(sk); | |
1038 | if (p->skb2 == NULL) { | |
68acc024 | 1039 | if (skb_shared(p->skb)) { |
1da177e4 LT |
1040 | p->skb2 = skb_clone(p->skb, p->allocation); |
1041 | } else { | |
68acc024 TC |
1042 | p->skb2 = skb_get(p->skb); |
1043 | /* | |
1044 | * skb ownership may have been set when | |
1045 | * delivered to a previous socket. | |
1046 | */ | |
1047 | skb_orphan(p->skb2); | |
1da177e4 LT |
1048 | } |
1049 | } | |
1050 | if (p->skb2 == NULL) { | |
1051 | netlink_overrun(sk); | |
1052 | /* Clone failed. Notify ALL listeners. */ | |
1053 | p->failure = 1; | |
be0c22a4 PNA |
1054 | if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR) |
1055 | p->delivery_failure = 1; | |
910a7e90 EB |
1056 | } else if (p->tx_filter && p->tx_filter(sk, p->skb2, p->tx_data)) { |
1057 | kfree_skb(p->skb2); | |
1058 | p->skb2 = NULL; | |
b1153f29 SH |
1059 | } else if (sk_filter(sk, p->skb2)) { |
1060 | kfree_skb(p->skb2); | |
1061 | p->skb2 = NULL; | |
1da177e4 LT |
1062 | } else if ((val = netlink_broadcast_deliver(sk, p->skb2)) < 0) { |
1063 | netlink_overrun(sk); | |
be0c22a4 PNA |
1064 | if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR) |
1065 | p->delivery_failure = 1; | |
1da177e4 LT |
1066 | } else { |
1067 | p->congested |= val; | |
1068 | p->delivered = 1; | |
1069 | p->skb2 = NULL; | |
1070 | } | |
1071 | sock_put(sk); | |
1072 | ||
1073 | out: | |
1074 | return 0; | |
1075 | } | |
1076 | ||
910a7e90 EB |
1077 | int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb, u32 pid, |
1078 | u32 group, gfp_t allocation, | |
1079 | int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data), | |
1080 | void *filter_data) | |
1da177e4 | 1081 | { |
3b1e0a65 | 1082 | struct net *net = sock_net(ssk); |
1da177e4 LT |
1083 | struct netlink_broadcast_data info; |
1084 | struct hlist_node *node; | |
1085 | struct sock *sk; | |
1086 | ||
1087 | skb = netlink_trim(skb, allocation); | |
1088 | ||
1089 | info.exclude_sk = ssk; | |
b4b51029 | 1090 | info.net = net; |
1da177e4 LT |
1091 | info.pid = pid; |
1092 | info.group = group; | |
1093 | info.failure = 0; | |
ff491a73 | 1094 | info.delivery_failure = 0; |
1da177e4 LT |
1095 | info.congested = 0; |
1096 | info.delivered = 0; | |
1097 | info.allocation = allocation; | |
1098 | info.skb = skb; | |
1099 | info.skb2 = NULL; | |
910a7e90 EB |
1100 | info.tx_filter = filter; |
1101 | info.tx_data = filter_data; | |
1da177e4 LT |
1102 | |
1103 | /* While we sleep in clone, do not allow to change socket list */ | |
1104 | ||
1105 | netlink_lock_table(); | |
1106 | ||
1107 | sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list) | |
1108 | do_one_broadcast(sk, &info); | |
1109 | ||
70d4bf6d | 1110 | consume_skb(skb); |
aa1c6a6f | 1111 | |
1da177e4 LT |
1112 | netlink_unlock_table(); |
1113 | ||
70d4bf6d NH |
1114 | if (info.delivery_failure) { |
1115 | kfree_skb(info.skb2); | |
ff491a73 | 1116 | return -ENOBUFS; |
658cb354 ED |
1117 | } |
1118 | consume_skb(info.skb2); | |
ff491a73 | 1119 | |
1da177e4 LT |
1120 | if (info.delivered) { |
1121 | if (info.congested && (allocation & __GFP_WAIT)) | |
1122 | yield(); | |
1123 | return 0; | |
1124 | } | |
1da177e4 LT |
1125 | return -ESRCH; |
1126 | } | |
910a7e90 EB |
1127 | EXPORT_SYMBOL(netlink_broadcast_filtered); |
1128 | ||
1129 | int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 pid, | |
1130 | u32 group, gfp_t allocation) | |
1131 | { | |
1132 | return netlink_broadcast_filtered(ssk, skb, pid, group, allocation, | |
1133 | NULL, NULL); | |
1134 | } | |
6ac552fd | 1135 | EXPORT_SYMBOL(netlink_broadcast); |
1da177e4 LT |
1136 | |
1137 | struct netlink_set_err_data { | |
1138 | struct sock *exclude_sk; | |
1139 | u32 pid; | |
1140 | u32 group; | |
1141 | int code; | |
1142 | }; | |
1143 | ||
b57ef81f | 1144 | static int do_one_set_err(struct sock *sk, struct netlink_set_err_data *p) |
1da177e4 LT |
1145 | { |
1146 | struct netlink_sock *nlk = nlk_sk(sk); | |
1a50307b | 1147 | int ret = 0; |
1da177e4 LT |
1148 | |
1149 | if (sk == p->exclude_sk) | |
1150 | goto out; | |
1151 | ||
09ad9bc7 | 1152 | if (!net_eq(sock_net(sk), sock_net(p->exclude_sk))) |
b4b51029 EB |
1153 | goto out; |
1154 | ||
f7fa9b10 PM |
1155 | if (nlk->pid == p->pid || p->group - 1 >= nlk->ngroups || |
1156 | !test_bit(p->group - 1, nlk->groups)) | |
1da177e4 LT |
1157 | goto out; |
1158 | ||
1a50307b PNA |
1159 | if (p->code == ENOBUFS && nlk->flags & NETLINK_RECV_NO_ENOBUFS) { |
1160 | ret = 1; | |
1161 | goto out; | |
1162 | } | |
1163 | ||
1da177e4 LT |
1164 | sk->sk_err = p->code; |
1165 | sk->sk_error_report(sk); | |
1166 | out: | |
1a50307b | 1167 | return ret; |
1da177e4 LT |
1168 | } |
1169 | ||
4843b93c PNA |
1170 | /** |
1171 | * netlink_set_err - report error to broadcast listeners | |
1172 | * @ssk: the kernel netlink socket, as returned by netlink_kernel_create() | |
1173 | * @pid: the PID of a process that we want to skip (if any) | |
1174 | * @groups: the broadcast group that will notice the error | |
1175 | * @code: error code, must be negative (as usual in kernelspace) | |
1a50307b PNA |
1176 | * |
1177 | * This function returns the number of broadcast listeners that have set the | |
1178 | * NETLINK_RECV_NO_ENOBUFS socket option. | |
4843b93c | 1179 | */ |
1a50307b | 1180 | int netlink_set_err(struct sock *ssk, u32 pid, u32 group, int code) |
1da177e4 LT |
1181 | { |
1182 | struct netlink_set_err_data info; | |
1183 | struct hlist_node *node; | |
1184 | struct sock *sk; | |
1a50307b | 1185 | int ret = 0; |
1da177e4 LT |
1186 | |
1187 | info.exclude_sk = ssk; | |
1188 | info.pid = pid; | |
1189 | info.group = group; | |
4843b93c PNA |
1190 | /* sk->sk_err wants a positive error value */ |
1191 | info.code = -code; | |
1da177e4 LT |
1192 | |
1193 | read_lock(&nl_table_lock); | |
1194 | ||
1195 | sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list) | |
1a50307b | 1196 | ret += do_one_set_err(sk, &info); |
1da177e4 LT |
1197 | |
1198 | read_unlock(&nl_table_lock); | |
1a50307b | 1199 | return ret; |
1da177e4 | 1200 | } |
dd5b6ce6 | 1201 | EXPORT_SYMBOL(netlink_set_err); |
1da177e4 | 1202 | |
84659eb5 JB |
1203 | /* must be called with netlink table grabbed */ |
1204 | static void netlink_update_socket_mc(struct netlink_sock *nlk, | |
1205 | unsigned int group, | |
1206 | int is_new) | |
1207 | { | |
1208 | int old, new = !!is_new, subscriptions; | |
1209 | ||
1210 | old = test_bit(group - 1, nlk->groups); | |
1211 | subscriptions = nlk->subscriptions - old + new; | |
1212 | if (new) | |
1213 | __set_bit(group - 1, nlk->groups); | |
1214 | else | |
1215 | __clear_bit(group - 1, nlk->groups); | |
1216 | netlink_update_subscriptions(&nlk->sk, subscriptions); | |
1217 | netlink_update_listeners(&nlk->sk); | |
1218 | } | |
1219 | ||
9a4595bc | 1220 | static int netlink_setsockopt(struct socket *sock, int level, int optname, |
b7058842 | 1221 | char __user *optval, unsigned int optlen) |
9a4595bc PM |
1222 | { |
1223 | struct sock *sk = sock->sk; | |
1224 | struct netlink_sock *nlk = nlk_sk(sk); | |
eb496534 JB |
1225 | unsigned int val = 0; |
1226 | int err; | |
9a4595bc PM |
1227 | |
1228 | if (level != SOL_NETLINK) | |
1229 | return -ENOPROTOOPT; | |
1230 | ||
1231 | if (optlen >= sizeof(int) && | |
eb496534 | 1232 | get_user(val, (unsigned int __user *)optval)) |
9a4595bc PM |
1233 | return -EFAULT; |
1234 | ||
1235 | switch (optname) { | |
1236 | case NETLINK_PKTINFO: | |
1237 | if (val) | |
1238 | nlk->flags |= NETLINK_RECV_PKTINFO; | |
1239 | else | |
1240 | nlk->flags &= ~NETLINK_RECV_PKTINFO; | |
1241 | err = 0; | |
1242 | break; | |
1243 | case NETLINK_ADD_MEMBERSHIP: | |
1244 | case NETLINK_DROP_MEMBERSHIP: { | |
9a4595bc PM |
1245 | if (!netlink_capable(sock, NL_NONROOT_RECV)) |
1246 | return -EPERM; | |
b4ff4f04 JB |
1247 | err = netlink_realloc_groups(sk); |
1248 | if (err) | |
1249 | return err; | |
9a4595bc PM |
1250 | if (!val || val - 1 >= nlk->ngroups) |
1251 | return -EINVAL; | |
1252 | netlink_table_grab(); | |
84659eb5 JB |
1253 | netlink_update_socket_mc(nlk, val, |
1254 | optname == NETLINK_ADD_MEMBERSHIP); | |
9a4595bc | 1255 | netlink_table_ungrab(); |
03292745 PNA |
1256 | |
1257 | if (nlk->netlink_bind) | |
1258 | nlk->netlink_bind(val); | |
1259 | ||
9a4595bc PM |
1260 | err = 0; |
1261 | break; | |
1262 | } | |
be0c22a4 PNA |
1263 | case NETLINK_BROADCAST_ERROR: |
1264 | if (val) | |
1265 | nlk->flags |= NETLINK_BROADCAST_SEND_ERROR; | |
1266 | else | |
1267 | nlk->flags &= ~NETLINK_BROADCAST_SEND_ERROR; | |
1268 | err = 0; | |
1269 | break; | |
38938bfe PNA |
1270 | case NETLINK_NO_ENOBUFS: |
1271 | if (val) { | |
1272 | nlk->flags |= NETLINK_RECV_NO_ENOBUFS; | |
1273 | clear_bit(0, &nlk->state); | |
1274 | wake_up_interruptible(&nlk->wait); | |
658cb354 | 1275 | } else { |
38938bfe | 1276 | nlk->flags &= ~NETLINK_RECV_NO_ENOBUFS; |
658cb354 | 1277 | } |
38938bfe PNA |
1278 | err = 0; |
1279 | break; | |
9a4595bc PM |
1280 | default: |
1281 | err = -ENOPROTOOPT; | |
1282 | } | |
1283 | return err; | |
1284 | } | |
1285 | ||
1286 | static int netlink_getsockopt(struct socket *sock, int level, int optname, | |
746fac4d | 1287 | char __user *optval, int __user *optlen) |
9a4595bc PM |
1288 | { |
1289 | struct sock *sk = sock->sk; | |
1290 | struct netlink_sock *nlk = nlk_sk(sk); | |
1291 | int len, val, err; | |
1292 | ||
1293 | if (level != SOL_NETLINK) | |
1294 | return -ENOPROTOOPT; | |
1295 | ||
1296 | if (get_user(len, optlen)) | |
1297 | return -EFAULT; | |
1298 | if (len < 0) | |
1299 | return -EINVAL; | |
1300 | ||
1301 | switch (optname) { | |
1302 | case NETLINK_PKTINFO: | |
1303 | if (len < sizeof(int)) | |
1304 | return -EINVAL; | |
1305 | len = sizeof(int); | |
1306 | val = nlk->flags & NETLINK_RECV_PKTINFO ? 1 : 0; | |
a27b58fe HC |
1307 | if (put_user(len, optlen) || |
1308 | put_user(val, optval)) | |
1309 | return -EFAULT; | |
9a4595bc PM |
1310 | err = 0; |
1311 | break; | |
be0c22a4 PNA |
1312 | case NETLINK_BROADCAST_ERROR: |
1313 | if (len < sizeof(int)) | |
1314 | return -EINVAL; | |
1315 | len = sizeof(int); | |
1316 | val = nlk->flags & NETLINK_BROADCAST_SEND_ERROR ? 1 : 0; | |
1317 | if (put_user(len, optlen) || | |
1318 | put_user(val, optval)) | |
1319 | return -EFAULT; | |
1320 | err = 0; | |
1321 | break; | |
38938bfe PNA |
1322 | case NETLINK_NO_ENOBUFS: |
1323 | if (len < sizeof(int)) | |
1324 | return -EINVAL; | |
1325 | len = sizeof(int); | |
1326 | val = nlk->flags & NETLINK_RECV_NO_ENOBUFS ? 1 : 0; | |
1327 | if (put_user(len, optlen) || | |
1328 | put_user(val, optval)) | |
1329 | return -EFAULT; | |
1330 | err = 0; | |
1331 | break; | |
9a4595bc PM |
1332 | default: |
1333 | err = -ENOPROTOOPT; | |
1334 | } | |
1335 | return err; | |
1336 | } | |
1337 | ||
1338 | static void netlink_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb) | |
1339 | { | |
1340 | struct nl_pktinfo info; | |
1341 | ||
1342 | info.group = NETLINK_CB(skb).dst_group; | |
1343 | put_cmsg(msg, SOL_NETLINK, NETLINK_PKTINFO, sizeof(info), &info); | |
1344 | } | |
1345 | ||
1da177e4 LT |
1346 | static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock, |
1347 | struct msghdr *msg, size_t len) | |
1348 | { | |
1349 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1350 | struct sock *sk = sock->sk; | |
1351 | struct netlink_sock *nlk = nlk_sk(sk); | |
6ac552fd | 1352 | struct sockaddr_nl *addr = msg->msg_name; |
1da177e4 | 1353 | u32 dst_pid; |
d629b836 | 1354 | u32 dst_group; |
1da177e4 LT |
1355 | struct sk_buff *skb; |
1356 | int err; | |
1357 | struct scm_cookie scm; | |
1358 | ||
1359 | if (msg->msg_flags&MSG_OOB) | |
1360 | return -EOPNOTSUPP; | |
1361 | ||
16e57262 | 1362 | if (NULL == siocb->scm) |
1da177e4 | 1363 | siocb->scm = &scm; |
16e57262 | 1364 | |
1da177e4 LT |
1365 | err = scm_send(sock, msg, siocb->scm); |
1366 | if (err < 0) | |
1367 | return err; | |
1368 | ||
1369 | if (msg->msg_namelen) { | |
b47030c7 | 1370 | err = -EINVAL; |
1da177e4 | 1371 | if (addr->nl_family != AF_NETLINK) |
b47030c7 | 1372 | goto out; |
1da177e4 | 1373 | dst_pid = addr->nl_pid; |
d629b836 | 1374 | dst_group = ffs(addr->nl_groups); |
b47030c7 | 1375 | err = -EPERM; |
d629b836 | 1376 | if (dst_group && !netlink_capable(sock, NL_NONROOT_SEND)) |
b47030c7 | 1377 | goto out; |
1da177e4 LT |
1378 | } else { |
1379 | dst_pid = nlk->dst_pid; | |
d629b836 | 1380 | dst_group = nlk->dst_group; |
1da177e4 LT |
1381 | } |
1382 | ||
1383 | if (!nlk->pid) { | |
1384 | err = netlink_autobind(sock); | |
1385 | if (err) | |
1386 | goto out; | |
1387 | } | |
1388 | ||
1389 | err = -EMSGSIZE; | |
1390 | if (len > sk->sk_sndbuf - 32) | |
1391 | goto out; | |
1392 | err = -ENOBUFS; | |
339bf98f | 1393 | skb = alloc_skb(len, GFP_KERNEL); |
6ac552fd | 1394 | if (skb == NULL) |
1da177e4 LT |
1395 | goto out; |
1396 | ||
1397 | NETLINK_CB(skb).pid = nlk->pid; | |
d629b836 | 1398 | NETLINK_CB(skb).dst_group = dst_group; |
1da177e4 LT |
1399 | memcpy(NETLINK_CREDS(skb), &siocb->scm->creds, sizeof(struct ucred)); |
1400 | ||
1da177e4 | 1401 | err = -EFAULT; |
6ac552fd | 1402 | if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) { |
1da177e4 LT |
1403 | kfree_skb(skb); |
1404 | goto out; | |
1405 | } | |
1406 | ||
1407 | err = security_netlink_send(sk, skb); | |
1408 | if (err) { | |
1409 | kfree_skb(skb); | |
1410 | goto out; | |
1411 | } | |
1412 | ||
d629b836 | 1413 | if (dst_group) { |
1da177e4 | 1414 | atomic_inc(&skb->users); |
d629b836 | 1415 | netlink_broadcast(sk, skb, dst_pid, dst_group, GFP_KERNEL); |
1da177e4 LT |
1416 | } |
1417 | err = netlink_unicast(sk, skb, dst_pid, msg->msg_flags&MSG_DONTWAIT); | |
1418 | ||
1419 | out: | |
b47030c7 | 1420 | scm_destroy(siocb->scm); |
1da177e4 LT |
1421 | return err; |
1422 | } | |
1423 | ||
1424 | static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock, | |
1425 | struct msghdr *msg, size_t len, | |
1426 | int flags) | |
1427 | { | |
1428 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1429 | struct scm_cookie scm; | |
1430 | struct sock *sk = sock->sk; | |
1431 | struct netlink_sock *nlk = nlk_sk(sk); | |
1432 | int noblock = flags&MSG_DONTWAIT; | |
1433 | size_t copied; | |
68d6ac6d | 1434 | struct sk_buff *skb, *data_skb; |
b44d211e | 1435 | int err, ret; |
1da177e4 LT |
1436 | |
1437 | if (flags&MSG_OOB) | |
1438 | return -EOPNOTSUPP; | |
1439 | ||
1440 | copied = 0; | |
1441 | ||
6ac552fd PM |
1442 | skb = skb_recv_datagram(sk, flags, noblock, &err); |
1443 | if (skb == NULL) | |
1da177e4 LT |
1444 | goto out; |
1445 | ||
68d6ac6d JB |
1446 | data_skb = skb; |
1447 | ||
1dacc76d JB |
1448 | #ifdef CONFIG_COMPAT_NETLINK_MESSAGES |
1449 | if (unlikely(skb_shinfo(skb)->frag_list)) { | |
1dacc76d | 1450 | /* |
68d6ac6d JB |
1451 | * If this skb has a frag_list, then here that means that we |
1452 | * will have to use the frag_list skb's data for compat tasks | |
1453 | * and the regular skb's data for normal (non-compat) tasks. | |
1dacc76d | 1454 | * |
68d6ac6d JB |
1455 | * If we need to send the compat skb, assign it to the |
1456 | * 'data_skb' variable so that it will be used below for data | |
1457 | * copying. We keep 'skb' for everything else, including | |
1458 | * freeing both later. | |
1dacc76d | 1459 | */ |
68d6ac6d JB |
1460 | if (flags & MSG_CMSG_COMPAT) |
1461 | data_skb = skb_shinfo(skb)->frag_list; | |
1dacc76d JB |
1462 | } |
1463 | #endif | |
1464 | ||
1da177e4 LT |
1465 | msg->msg_namelen = 0; |
1466 | ||
68d6ac6d | 1467 | copied = data_skb->len; |
1da177e4 LT |
1468 | if (len < copied) { |
1469 | msg->msg_flags |= MSG_TRUNC; | |
1470 | copied = len; | |
1471 | } | |
1472 | ||
68d6ac6d JB |
1473 | skb_reset_transport_header(data_skb); |
1474 | err = skb_copy_datagram_iovec(data_skb, 0, msg->msg_iov, copied); | |
1da177e4 LT |
1475 | |
1476 | if (msg->msg_name) { | |
6ac552fd | 1477 | struct sockaddr_nl *addr = (struct sockaddr_nl *)msg->msg_name; |
1da177e4 LT |
1478 | addr->nl_family = AF_NETLINK; |
1479 | addr->nl_pad = 0; | |
1480 | addr->nl_pid = NETLINK_CB(skb).pid; | |
d629b836 | 1481 | addr->nl_groups = netlink_group_mask(NETLINK_CB(skb).dst_group); |
1da177e4 LT |
1482 | msg->msg_namelen = sizeof(*addr); |
1483 | } | |
1484 | ||
cc9a06cd PM |
1485 | if (nlk->flags & NETLINK_RECV_PKTINFO) |
1486 | netlink_cmsg_recv_pktinfo(msg, skb); | |
1487 | ||
1da177e4 LT |
1488 | if (NULL == siocb->scm) { |
1489 | memset(&scm, 0, sizeof(scm)); | |
1490 | siocb->scm = &scm; | |
1491 | } | |
1492 | siocb->scm->creds = *NETLINK_CREDS(skb); | |
188ccb55 | 1493 | if (flags & MSG_TRUNC) |
68d6ac6d | 1494 | copied = data_skb->len; |
daa3766e | 1495 | |
1da177e4 LT |
1496 | skb_free_datagram(sk, skb); |
1497 | ||
b44d211e AV |
1498 | if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) { |
1499 | ret = netlink_dump(sk); | |
1500 | if (ret) { | |
1501 | sk->sk_err = ret; | |
1502 | sk->sk_error_report(sk); | |
1503 | } | |
1504 | } | |
1da177e4 LT |
1505 | |
1506 | scm_recv(sock, msg, siocb->scm, flags); | |
1da177e4 LT |
1507 | out: |
1508 | netlink_rcv_wake(sk); | |
1509 | return err ? : copied; | |
1510 | } | |
1511 | ||
1512 | static void netlink_data_ready(struct sock *sk, int len) | |
1513 | { | |
cd40b7d3 | 1514 | BUG(); |
1da177e4 LT |
1515 | } |
1516 | ||
1517 | /* | |
746fac4d | 1518 | * We export these functions to other modules. They provide a |
1da177e4 LT |
1519 | * complete set of kernel non-blocking support for message |
1520 | * queueing. | |
1521 | */ | |
1522 | ||
1523 | struct sock * | |
a31f2d17 PNA |
1524 | netlink_kernel_create(struct net *net, int unit, |
1525 | struct module *module, | |
1526 | struct netlink_kernel_cfg *cfg) | |
1da177e4 LT |
1527 | { |
1528 | struct socket *sock; | |
1529 | struct sock *sk; | |
77247bbb | 1530 | struct netlink_sock *nlk; |
5c398dc8 | 1531 | struct listeners *listeners = NULL; |
a31f2d17 PNA |
1532 | struct mutex *cb_mutex = cfg ? cfg->cb_mutex : NULL; |
1533 | unsigned int groups; | |
1da177e4 | 1534 | |
fab2caf6 | 1535 | BUG_ON(!nl_table); |
1da177e4 | 1536 | |
6ac552fd | 1537 | if (unit < 0 || unit >= MAX_LINKS) |
1da177e4 LT |
1538 | return NULL; |
1539 | ||
1540 | if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock)) | |
1541 | return NULL; | |
1542 | ||
23fe1866 PE |
1543 | /* |
1544 | * We have to just have a reference on the net from sk, but don't | |
1545 | * get_net it. Besides, we cannot get and then put the net here. | |
1546 | * So we create one inside init_net and the move it to net. | |
1547 | */ | |
1548 | ||
1549 | if (__netlink_create(&init_net, sock, cb_mutex, unit) < 0) | |
1550 | goto out_sock_release_nosk; | |
1551 | ||
1552 | sk = sock->sk; | |
edf02087 | 1553 | sk_change_net(sk, net); |
4fdb3bb7 | 1554 | |
a31f2d17 | 1555 | if (!cfg || cfg->groups < 32) |
4277a083 | 1556 | groups = 32; |
a31f2d17 PNA |
1557 | else |
1558 | groups = cfg->groups; | |
4277a083 | 1559 | |
5c398dc8 | 1560 | listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL); |
4277a083 PM |
1561 | if (!listeners) |
1562 | goto out_sock_release; | |
1563 | ||
1da177e4 | 1564 | sk->sk_data_ready = netlink_data_ready; |
a31f2d17 PNA |
1565 | if (cfg && cfg->input) |
1566 | nlk_sk(sk)->netlink_rcv = cfg->input; | |
1da177e4 | 1567 | |
b4b51029 | 1568 | if (netlink_insert(sk, net, 0)) |
77247bbb | 1569 | goto out_sock_release; |
4fdb3bb7 | 1570 | |
77247bbb PM |
1571 | nlk = nlk_sk(sk); |
1572 | nlk->flags |= NETLINK_KERNEL_SOCKET; | |
4fdb3bb7 | 1573 | |
4fdb3bb7 | 1574 | netlink_table_grab(); |
b4b51029 EB |
1575 | if (!nl_table[unit].registered) { |
1576 | nl_table[unit].groups = groups; | |
5c398dc8 | 1577 | rcu_assign_pointer(nl_table[unit].listeners, listeners); |
b4b51029 EB |
1578 | nl_table[unit].cb_mutex = cb_mutex; |
1579 | nl_table[unit].module = module; | |
03292745 | 1580 | nl_table[unit].bind = cfg ? cfg->bind : NULL; |
b4b51029 | 1581 | nl_table[unit].registered = 1; |
f937f1f4 JJ |
1582 | } else { |
1583 | kfree(listeners); | |
869e58f8 | 1584 | nl_table[unit].registered++; |
b4b51029 | 1585 | } |
4fdb3bb7 | 1586 | netlink_table_ungrab(); |
77247bbb PM |
1587 | return sk; |
1588 | ||
4fdb3bb7 | 1589 | out_sock_release: |
4277a083 | 1590 | kfree(listeners); |
9dfbec1f | 1591 | netlink_kernel_release(sk); |
23fe1866 PE |
1592 | return NULL; |
1593 | ||
1594 | out_sock_release_nosk: | |
4fdb3bb7 | 1595 | sock_release(sock); |
77247bbb | 1596 | return NULL; |
1da177e4 | 1597 | } |
6ac552fd | 1598 | EXPORT_SYMBOL(netlink_kernel_create); |
1da177e4 | 1599 | |
b7c6ba6e DL |
1600 | |
1601 | void | |
1602 | netlink_kernel_release(struct sock *sk) | |
1603 | { | |
edf02087 | 1604 | sk_release_kernel(sk); |
b7c6ba6e DL |
1605 | } |
1606 | EXPORT_SYMBOL(netlink_kernel_release); | |
1607 | ||
d136f1bd | 1608 | int __netlink_change_ngroups(struct sock *sk, unsigned int groups) |
b4ff4f04 | 1609 | { |
5c398dc8 | 1610 | struct listeners *new, *old; |
b4ff4f04 | 1611 | struct netlink_table *tbl = &nl_table[sk->sk_protocol]; |
b4ff4f04 JB |
1612 | |
1613 | if (groups < 32) | |
1614 | groups = 32; | |
1615 | ||
b4ff4f04 | 1616 | if (NLGRPSZ(tbl->groups) < NLGRPSZ(groups)) { |
5c398dc8 ED |
1617 | new = kzalloc(sizeof(*new) + NLGRPSZ(groups), GFP_ATOMIC); |
1618 | if (!new) | |
d136f1bd | 1619 | return -ENOMEM; |
33d480ce | 1620 | old = rcu_dereference_protected(tbl->listeners, 1); |
5c398dc8 ED |
1621 | memcpy(new->masks, old->masks, NLGRPSZ(tbl->groups)); |
1622 | rcu_assign_pointer(tbl->listeners, new); | |
1623 | ||
37b6b935 | 1624 | kfree_rcu(old, rcu); |
b4ff4f04 JB |
1625 | } |
1626 | tbl->groups = groups; | |
1627 | ||
d136f1bd JB |
1628 | return 0; |
1629 | } | |
1630 | ||
1631 | /** | |
1632 | * netlink_change_ngroups - change number of multicast groups | |
1633 | * | |
1634 | * This changes the number of multicast groups that are available | |
1635 | * on a certain netlink family. Note that it is not possible to | |
1636 | * change the number of groups to below 32. Also note that it does | |
1637 | * not implicitly call netlink_clear_multicast_users() when the | |
1638 | * number of groups is reduced. | |
1639 | * | |
1640 | * @sk: The kernel netlink socket, as returned by netlink_kernel_create(). | |
1641 | * @groups: The new number of groups. | |
1642 | */ | |
1643 | int netlink_change_ngroups(struct sock *sk, unsigned int groups) | |
1644 | { | |
1645 | int err; | |
1646 | ||
1647 | netlink_table_grab(); | |
1648 | err = __netlink_change_ngroups(sk, groups); | |
b4ff4f04 | 1649 | netlink_table_ungrab(); |
d136f1bd | 1650 | |
b4ff4f04 JB |
1651 | return err; |
1652 | } | |
b4ff4f04 | 1653 | |
b8273570 JB |
1654 | void __netlink_clear_multicast_users(struct sock *ksk, unsigned int group) |
1655 | { | |
1656 | struct sock *sk; | |
1657 | struct hlist_node *node; | |
1658 | struct netlink_table *tbl = &nl_table[ksk->sk_protocol]; | |
1659 | ||
1660 | sk_for_each_bound(sk, node, &tbl->mc_list) | |
1661 | netlink_update_socket_mc(nlk_sk(sk), group, 0); | |
1662 | } | |
1663 | ||
84659eb5 JB |
1664 | /** |
1665 | * netlink_clear_multicast_users - kick off multicast listeners | |
1666 | * | |
1667 | * This function removes all listeners from the given group. | |
1668 | * @ksk: The kernel netlink socket, as returned by | |
1669 | * netlink_kernel_create(). | |
1670 | * @group: The multicast group to clear. | |
1671 | */ | |
1672 | void netlink_clear_multicast_users(struct sock *ksk, unsigned int group) | |
1673 | { | |
84659eb5 | 1674 | netlink_table_grab(); |
b8273570 | 1675 | __netlink_clear_multicast_users(ksk, group); |
84659eb5 JB |
1676 | netlink_table_ungrab(); |
1677 | } | |
84659eb5 | 1678 | |
1da177e4 | 1679 | void netlink_set_nonroot(int protocol, unsigned int flags) |
746fac4d YH |
1680 | { |
1681 | if ((unsigned int)protocol < MAX_LINKS) | |
1da177e4 | 1682 | nl_table[protocol].nl_nonroot = flags; |
746fac4d | 1683 | } |
6ac552fd | 1684 | EXPORT_SYMBOL(netlink_set_nonroot); |
1da177e4 | 1685 | |
a46621a3 DV |
1686 | struct nlmsghdr * |
1687 | __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags) | |
1688 | { | |
1689 | struct nlmsghdr *nlh; | |
1690 | int size = NLMSG_LENGTH(len); | |
1691 | ||
1692 | nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size)); | |
1693 | nlh->nlmsg_type = type; | |
1694 | nlh->nlmsg_len = size; | |
1695 | nlh->nlmsg_flags = flags; | |
1696 | nlh->nlmsg_pid = pid; | |
1697 | nlh->nlmsg_seq = seq; | |
1698 | if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0) | |
1699 | memset(NLMSG_DATA(nlh) + len, 0, NLMSG_ALIGN(size) - size); | |
1700 | return nlh; | |
1701 | } | |
1702 | EXPORT_SYMBOL(__nlmsg_put); | |
1703 | ||
1da177e4 LT |
1704 | /* |
1705 | * It looks a bit ugly. | |
1706 | * It would be better to create kernel thread. | |
1707 | */ | |
1708 | ||
1709 | static int netlink_dump(struct sock *sk) | |
1710 | { | |
1711 | struct netlink_sock *nlk = nlk_sk(sk); | |
1712 | struct netlink_callback *cb; | |
c7ac8679 | 1713 | struct sk_buff *skb = NULL; |
1da177e4 | 1714 | struct nlmsghdr *nlh; |
bf8b79e4 | 1715 | int len, err = -ENOBUFS; |
c7ac8679 | 1716 | int alloc_size; |
1da177e4 | 1717 | |
af65bdfc | 1718 | mutex_lock(nlk->cb_mutex); |
1da177e4 LT |
1719 | |
1720 | cb = nlk->cb; | |
1721 | if (cb == NULL) { | |
bf8b79e4 TG |
1722 | err = -EINVAL; |
1723 | goto errout_skb; | |
1da177e4 LT |
1724 | } |
1725 | ||
c7ac8679 GR |
1726 | alloc_size = max_t(int, cb->min_dump_alloc, NLMSG_GOODSIZE); |
1727 | ||
1728 | skb = sock_rmalloc(sk, alloc_size, 0, GFP_KERNEL); | |
1729 | if (!skb) | |
c63d6ea3 | 1730 | goto errout_skb; |
c7ac8679 | 1731 | |
1da177e4 LT |
1732 | len = cb->dump(skb, cb); |
1733 | ||
1734 | if (len > 0) { | |
af65bdfc | 1735 | mutex_unlock(nlk->cb_mutex); |
b1153f29 SH |
1736 | |
1737 | if (sk_filter(sk, skb)) | |
1738 | kfree_skb(skb); | |
4a7e7c2a ED |
1739 | else |
1740 | __netlink_sendskb(sk, skb); | |
1da177e4 LT |
1741 | return 0; |
1742 | } | |
1743 | ||
bf8b79e4 TG |
1744 | nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI); |
1745 | if (!nlh) | |
1746 | goto errout_skb; | |
1747 | ||
670dc283 JB |
1748 | nl_dump_check_consistent(cb, nlh); |
1749 | ||
bf8b79e4 TG |
1750 | memcpy(nlmsg_data(nlh), &len, sizeof(len)); |
1751 | ||
b1153f29 SH |
1752 | if (sk_filter(sk, skb)) |
1753 | kfree_skb(skb); | |
4a7e7c2a ED |
1754 | else |
1755 | __netlink_sendskb(sk, skb); | |
1da177e4 | 1756 | |
a8f74b22 TG |
1757 | if (cb->done) |
1758 | cb->done(cb); | |
1da177e4 | 1759 | nlk->cb = NULL; |
af65bdfc | 1760 | mutex_unlock(nlk->cb_mutex); |
1da177e4 | 1761 | |
bfb253c9 | 1762 | netlink_consume_callback(cb); |
1da177e4 | 1763 | return 0; |
1797754e | 1764 | |
bf8b79e4 | 1765 | errout_skb: |
af65bdfc | 1766 | mutex_unlock(nlk->cb_mutex); |
bf8b79e4 | 1767 | kfree_skb(skb); |
bf8b79e4 | 1768 | return err; |
1da177e4 LT |
1769 | } |
1770 | ||
1771 | int netlink_dump_start(struct sock *ssk, struct sk_buff *skb, | |
3a6c2b41 | 1772 | const struct nlmsghdr *nlh, |
80d326fa | 1773 | struct netlink_dump_control *control) |
1da177e4 LT |
1774 | { |
1775 | struct netlink_callback *cb; | |
1776 | struct sock *sk; | |
1777 | struct netlink_sock *nlk; | |
b44d211e | 1778 | int ret; |
1da177e4 | 1779 | |
0da974f4 | 1780 | cb = kzalloc(sizeof(*cb), GFP_KERNEL); |
1da177e4 LT |
1781 | if (cb == NULL) |
1782 | return -ENOBUFS; | |
1783 | ||
80d326fa PNA |
1784 | cb->dump = control->dump; |
1785 | cb->done = control->done; | |
1da177e4 | 1786 | cb->nlh = nlh; |
7175c883 | 1787 | cb->data = control->data; |
80d326fa | 1788 | cb->min_dump_alloc = control->min_dump_alloc; |
1da177e4 LT |
1789 | atomic_inc(&skb->users); |
1790 | cb->skb = skb; | |
1791 | ||
3b1e0a65 | 1792 | sk = netlink_lookup(sock_net(ssk), ssk->sk_protocol, NETLINK_CB(skb).pid); |
1da177e4 LT |
1793 | if (sk == NULL) { |
1794 | netlink_destroy_callback(cb); | |
1795 | return -ECONNREFUSED; | |
1796 | } | |
1797 | nlk = nlk_sk(sk); | |
3f660d66 | 1798 | /* A dump is in progress... */ |
af65bdfc | 1799 | mutex_lock(nlk->cb_mutex); |
3f660d66 | 1800 | if (nlk->cb) { |
af65bdfc | 1801 | mutex_unlock(nlk->cb_mutex); |
1da177e4 LT |
1802 | netlink_destroy_callback(cb); |
1803 | sock_put(sk); | |
1804 | return -EBUSY; | |
1805 | } | |
1806 | nlk->cb = cb; | |
af65bdfc | 1807 | mutex_unlock(nlk->cb_mutex); |
1da177e4 | 1808 | |
b44d211e AV |
1809 | ret = netlink_dump(sk); |
1810 | ||
1da177e4 | 1811 | sock_put(sk); |
5c58298c | 1812 | |
b44d211e AV |
1813 | if (ret) |
1814 | return ret; | |
1815 | ||
5c58298c DL |
1816 | /* We successfully started a dump, by returning -EINTR we |
1817 | * signal not to send ACK even if it was requested. | |
1818 | */ | |
1819 | return -EINTR; | |
1da177e4 | 1820 | } |
6ac552fd | 1821 | EXPORT_SYMBOL(netlink_dump_start); |
1da177e4 LT |
1822 | |
1823 | void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err) | |
1824 | { | |
1825 | struct sk_buff *skb; | |
1826 | struct nlmsghdr *rep; | |
1827 | struct nlmsgerr *errmsg; | |
339bf98f | 1828 | size_t payload = sizeof(*errmsg); |
1da177e4 | 1829 | |
339bf98f TG |
1830 | /* error messages get the original request appened */ |
1831 | if (err) | |
1832 | payload += nlmsg_len(nlh); | |
1da177e4 | 1833 | |
339bf98f | 1834 | skb = nlmsg_new(payload, GFP_KERNEL); |
1da177e4 LT |
1835 | if (!skb) { |
1836 | struct sock *sk; | |
1837 | ||
3b1e0a65 | 1838 | sk = netlink_lookup(sock_net(in_skb->sk), |
b4b51029 | 1839 | in_skb->sk->sk_protocol, |
1da177e4 LT |
1840 | NETLINK_CB(in_skb).pid); |
1841 | if (sk) { | |
1842 | sk->sk_err = ENOBUFS; | |
1843 | sk->sk_error_report(sk); | |
1844 | sock_put(sk); | |
1845 | } | |
1846 | return; | |
1847 | } | |
1848 | ||
1849 | rep = __nlmsg_put(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, | |
5dba93ae | 1850 | NLMSG_ERROR, payload, 0); |
bf8b79e4 | 1851 | errmsg = nlmsg_data(rep); |
1da177e4 | 1852 | errmsg->error = err; |
bf8b79e4 | 1853 | memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(*nlh)); |
1da177e4 LT |
1854 | netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).pid, MSG_DONTWAIT); |
1855 | } | |
6ac552fd | 1856 | EXPORT_SYMBOL(netlink_ack); |
1da177e4 | 1857 | |
cd40b7d3 | 1858 | int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *, |
1d00a4eb | 1859 | struct nlmsghdr *)) |
82ace47a | 1860 | { |
82ace47a TG |
1861 | struct nlmsghdr *nlh; |
1862 | int err; | |
1863 | ||
1864 | while (skb->len >= nlmsg_total_size(0)) { | |
cd40b7d3 DL |
1865 | int msglen; |
1866 | ||
b529ccf2 | 1867 | nlh = nlmsg_hdr(skb); |
d35b6856 | 1868 | err = 0; |
82ace47a | 1869 | |
ad8e4b75 | 1870 | if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len) |
82ace47a TG |
1871 | return 0; |
1872 | ||
d35b6856 TG |
1873 | /* Only requests are handled by the kernel */ |
1874 | if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) | |
5c58298c | 1875 | goto ack; |
45e7ae7f TG |
1876 | |
1877 | /* Skip control messages */ | |
1878 | if (nlh->nlmsg_type < NLMSG_MIN_TYPE) | |
5c58298c | 1879 | goto ack; |
d35b6856 | 1880 | |
1d00a4eb | 1881 | err = cb(skb, nlh); |
5c58298c DL |
1882 | if (err == -EINTR) |
1883 | goto skip; | |
1884 | ||
1885 | ack: | |
d35b6856 | 1886 | if (nlh->nlmsg_flags & NLM_F_ACK || err) |
82ace47a | 1887 | netlink_ack(skb, nlh, err); |
82ace47a | 1888 | |
5c58298c | 1889 | skip: |
6ac552fd | 1890 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); |
cd40b7d3 DL |
1891 | if (msglen > skb->len) |
1892 | msglen = skb->len; | |
1893 | skb_pull(skb, msglen); | |
82ace47a TG |
1894 | } |
1895 | ||
1896 | return 0; | |
1897 | } | |
6ac552fd | 1898 | EXPORT_SYMBOL(netlink_rcv_skb); |
82ace47a | 1899 | |
d387f6ad TG |
1900 | /** |
1901 | * nlmsg_notify - send a notification netlink message | |
1902 | * @sk: netlink socket to use | |
1903 | * @skb: notification message | |
1904 | * @pid: destination netlink pid for reports or 0 | |
1905 | * @group: destination multicast group or 0 | |
1906 | * @report: 1 to report back, 0 to disable | |
1907 | * @flags: allocation flags | |
1908 | */ | |
1909 | int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 pid, | |
1910 | unsigned int group, int report, gfp_t flags) | |
1911 | { | |
1912 | int err = 0; | |
1913 | ||
1914 | if (group) { | |
1915 | int exclude_pid = 0; | |
1916 | ||
1917 | if (report) { | |
1918 | atomic_inc(&skb->users); | |
1919 | exclude_pid = pid; | |
1920 | } | |
1921 | ||
1ce85fe4 PNA |
1922 | /* errors reported via destination sk->sk_err, but propagate |
1923 | * delivery errors if NETLINK_BROADCAST_ERROR flag is set */ | |
1924 | err = nlmsg_multicast(sk, skb, exclude_pid, group, flags); | |
d387f6ad TG |
1925 | } |
1926 | ||
1ce85fe4 PNA |
1927 | if (report) { |
1928 | int err2; | |
1929 | ||
1930 | err2 = nlmsg_unicast(sk, skb, pid); | |
1931 | if (!err || err == -ESRCH) | |
1932 | err = err2; | |
1933 | } | |
d387f6ad TG |
1934 | |
1935 | return err; | |
1936 | } | |
6ac552fd | 1937 | EXPORT_SYMBOL(nlmsg_notify); |
d387f6ad | 1938 | |
1da177e4 LT |
1939 | #ifdef CONFIG_PROC_FS |
1940 | struct nl_seq_iter { | |
e372c414 | 1941 | struct seq_net_private p; |
1da177e4 LT |
1942 | int link; |
1943 | int hash_idx; | |
1944 | }; | |
1945 | ||
1946 | static struct sock *netlink_seq_socket_idx(struct seq_file *seq, loff_t pos) | |
1947 | { | |
1948 | struct nl_seq_iter *iter = seq->private; | |
1949 | int i, j; | |
1950 | struct sock *s; | |
1951 | struct hlist_node *node; | |
1952 | loff_t off = 0; | |
1953 | ||
6ac552fd | 1954 | for (i = 0; i < MAX_LINKS; i++) { |
1da177e4 LT |
1955 | struct nl_pid_hash *hash = &nl_table[i].hash; |
1956 | ||
1957 | for (j = 0; j <= hash->mask; j++) { | |
1958 | sk_for_each(s, node, &hash->table[j]) { | |
1218854a | 1959 | if (sock_net(s) != seq_file_net(seq)) |
b4b51029 | 1960 | continue; |
1da177e4 LT |
1961 | if (off == pos) { |
1962 | iter->link = i; | |
1963 | iter->hash_idx = j; | |
1964 | return s; | |
1965 | } | |
1966 | ++off; | |
1967 | } | |
1968 | } | |
1969 | } | |
1970 | return NULL; | |
1971 | } | |
1972 | ||
1973 | static void *netlink_seq_start(struct seq_file *seq, loff_t *pos) | |
9a429c49 | 1974 | __acquires(nl_table_lock) |
1da177e4 LT |
1975 | { |
1976 | read_lock(&nl_table_lock); | |
1977 | return *pos ? netlink_seq_socket_idx(seq, *pos - 1) : SEQ_START_TOKEN; | |
1978 | } | |
1979 | ||
1980 | static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
1981 | { | |
1982 | struct sock *s; | |
1983 | struct nl_seq_iter *iter; | |
1984 | int i, j; | |
1985 | ||
1986 | ++*pos; | |
1987 | ||
1988 | if (v == SEQ_START_TOKEN) | |
1989 | return netlink_seq_socket_idx(seq, 0); | |
746fac4d | 1990 | |
b4b51029 EB |
1991 | iter = seq->private; |
1992 | s = v; | |
1993 | do { | |
1994 | s = sk_next(s); | |
1218854a | 1995 | } while (s && sock_net(s) != seq_file_net(seq)); |
1da177e4 LT |
1996 | if (s) |
1997 | return s; | |
1998 | ||
1da177e4 LT |
1999 | i = iter->link; |
2000 | j = iter->hash_idx + 1; | |
2001 | ||
2002 | do { | |
2003 | struct nl_pid_hash *hash = &nl_table[i].hash; | |
2004 | ||
2005 | for (; j <= hash->mask; j++) { | |
2006 | s = sk_head(&hash->table[j]); | |
1218854a | 2007 | while (s && sock_net(s) != seq_file_net(seq)) |
b4b51029 | 2008 | s = sk_next(s); |
1da177e4 LT |
2009 | if (s) { |
2010 | iter->link = i; | |
2011 | iter->hash_idx = j; | |
2012 | return s; | |
2013 | } | |
2014 | } | |
2015 | ||
2016 | j = 0; | |
2017 | } while (++i < MAX_LINKS); | |
2018 | ||
2019 | return NULL; | |
2020 | } | |
2021 | ||
2022 | static void netlink_seq_stop(struct seq_file *seq, void *v) | |
9a429c49 | 2023 | __releases(nl_table_lock) |
1da177e4 LT |
2024 | { |
2025 | read_unlock(&nl_table_lock); | |
2026 | } | |
2027 | ||
2028 | ||
2029 | static int netlink_seq_show(struct seq_file *seq, void *v) | |
2030 | { | |
658cb354 | 2031 | if (v == SEQ_START_TOKEN) { |
1da177e4 LT |
2032 | seq_puts(seq, |
2033 | "sk Eth Pid Groups " | |
cf0aa4e0 | 2034 | "Rmem Wmem Dump Locks Drops Inode\n"); |
658cb354 | 2035 | } else { |
1da177e4 LT |
2036 | struct sock *s = v; |
2037 | struct netlink_sock *nlk = nlk_sk(s); | |
2038 | ||
71338aa7 | 2039 | seq_printf(seq, "%pK %-3d %-6d %08x %-8d %-8d %pK %-8d %-8d %-8lu\n", |
1da177e4 LT |
2040 | s, |
2041 | s->sk_protocol, | |
2042 | nlk->pid, | |
513c2500 | 2043 | nlk->groups ? (u32)nlk->groups[0] : 0, |
31e6d363 ED |
2044 | sk_rmem_alloc_get(s), |
2045 | sk_wmem_alloc_get(s), | |
1da177e4 | 2046 | nlk->cb, |
38938bfe | 2047 | atomic_read(&s->sk_refcnt), |
cf0aa4e0 MY |
2048 | atomic_read(&s->sk_drops), |
2049 | sock_i_ino(s) | |
1da177e4 LT |
2050 | ); |
2051 | ||
2052 | } | |
2053 | return 0; | |
2054 | } | |
2055 | ||
56b3d975 | 2056 | static const struct seq_operations netlink_seq_ops = { |
1da177e4 LT |
2057 | .start = netlink_seq_start, |
2058 | .next = netlink_seq_next, | |
2059 | .stop = netlink_seq_stop, | |
2060 | .show = netlink_seq_show, | |
2061 | }; | |
2062 | ||
2063 | ||
2064 | static int netlink_seq_open(struct inode *inode, struct file *file) | |
2065 | { | |
e372c414 DL |
2066 | return seq_open_net(inode, file, &netlink_seq_ops, |
2067 | sizeof(struct nl_seq_iter)); | |
b4b51029 EB |
2068 | } |
2069 | ||
da7071d7 | 2070 | static const struct file_operations netlink_seq_fops = { |
1da177e4 LT |
2071 | .owner = THIS_MODULE, |
2072 | .open = netlink_seq_open, | |
2073 | .read = seq_read, | |
2074 | .llseek = seq_lseek, | |
e372c414 | 2075 | .release = seq_release_net, |
1da177e4 LT |
2076 | }; |
2077 | ||
2078 | #endif | |
2079 | ||
2080 | int netlink_register_notifier(struct notifier_block *nb) | |
2081 | { | |
e041c683 | 2082 | return atomic_notifier_chain_register(&netlink_chain, nb); |
1da177e4 | 2083 | } |
6ac552fd | 2084 | EXPORT_SYMBOL(netlink_register_notifier); |
1da177e4 LT |
2085 | |
2086 | int netlink_unregister_notifier(struct notifier_block *nb) | |
2087 | { | |
e041c683 | 2088 | return atomic_notifier_chain_unregister(&netlink_chain, nb); |
1da177e4 | 2089 | } |
6ac552fd | 2090 | EXPORT_SYMBOL(netlink_unregister_notifier); |
746fac4d | 2091 | |
90ddc4f0 | 2092 | static const struct proto_ops netlink_ops = { |
1da177e4 LT |
2093 | .family = PF_NETLINK, |
2094 | .owner = THIS_MODULE, | |
2095 | .release = netlink_release, | |
2096 | .bind = netlink_bind, | |
2097 | .connect = netlink_connect, | |
2098 | .socketpair = sock_no_socketpair, | |
2099 | .accept = sock_no_accept, | |
2100 | .getname = netlink_getname, | |
2101 | .poll = datagram_poll, | |
2102 | .ioctl = sock_no_ioctl, | |
2103 | .listen = sock_no_listen, | |
2104 | .shutdown = sock_no_shutdown, | |
9a4595bc PM |
2105 | .setsockopt = netlink_setsockopt, |
2106 | .getsockopt = netlink_getsockopt, | |
1da177e4 LT |
2107 | .sendmsg = netlink_sendmsg, |
2108 | .recvmsg = netlink_recvmsg, | |
2109 | .mmap = sock_no_mmap, | |
2110 | .sendpage = sock_no_sendpage, | |
2111 | }; | |
2112 | ||
ec1b4cf7 | 2113 | static const struct net_proto_family netlink_family_ops = { |
1da177e4 LT |
2114 | .family = PF_NETLINK, |
2115 | .create = netlink_create, | |
2116 | .owner = THIS_MODULE, /* for consistency 8) */ | |
2117 | }; | |
2118 | ||
4665079c | 2119 | static int __net_init netlink_net_init(struct net *net) |
b4b51029 EB |
2120 | { |
2121 | #ifdef CONFIG_PROC_FS | |
2122 | if (!proc_net_fops_create(net, "netlink", 0, &netlink_seq_fops)) | |
2123 | return -ENOMEM; | |
2124 | #endif | |
2125 | return 0; | |
2126 | } | |
2127 | ||
4665079c | 2128 | static void __net_exit netlink_net_exit(struct net *net) |
b4b51029 EB |
2129 | { |
2130 | #ifdef CONFIG_PROC_FS | |
2131 | proc_net_remove(net, "netlink"); | |
2132 | #endif | |
2133 | } | |
2134 | ||
b963ea89 DM |
2135 | static void __init netlink_add_usersock_entry(void) |
2136 | { | |
5c398dc8 | 2137 | struct listeners *listeners; |
b963ea89 DM |
2138 | int groups = 32; |
2139 | ||
5c398dc8 | 2140 | listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL); |
b963ea89 | 2141 | if (!listeners) |
5c398dc8 | 2142 | panic("netlink_add_usersock_entry: Cannot allocate listeners\n"); |
b963ea89 DM |
2143 | |
2144 | netlink_table_grab(); | |
2145 | ||
2146 | nl_table[NETLINK_USERSOCK].groups = groups; | |
5c398dc8 | 2147 | rcu_assign_pointer(nl_table[NETLINK_USERSOCK].listeners, listeners); |
b963ea89 DM |
2148 | nl_table[NETLINK_USERSOCK].module = THIS_MODULE; |
2149 | nl_table[NETLINK_USERSOCK].registered = 1; | |
2150 | ||
2151 | netlink_table_ungrab(); | |
2152 | } | |
2153 | ||
022cbae6 | 2154 | static struct pernet_operations __net_initdata netlink_net_ops = { |
b4b51029 EB |
2155 | .init = netlink_net_init, |
2156 | .exit = netlink_net_exit, | |
2157 | }; | |
2158 | ||
1da177e4 LT |
2159 | static int __init netlink_proto_init(void) |
2160 | { | |
2161 | struct sk_buff *dummy_skb; | |
2162 | int i; | |
26ff5ddc | 2163 | unsigned long limit; |
1da177e4 LT |
2164 | unsigned int order; |
2165 | int err = proto_register(&netlink_proto, 0); | |
2166 | ||
2167 | if (err != 0) | |
2168 | goto out; | |
2169 | ||
ef047f5e | 2170 | BUILD_BUG_ON(sizeof(struct netlink_skb_parms) > sizeof(dummy_skb->cb)); |
1da177e4 | 2171 | |
0da974f4 | 2172 | nl_table = kcalloc(MAX_LINKS, sizeof(*nl_table), GFP_KERNEL); |
fab2caf6 AM |
2173 | if (!nl_table) |
2174 | goto panic; | |
1da177e4 | 2175 | |
4481374c JB |
2176 | if (totalram_pages >= (128 * 1024)) |
2177 | limit = totalram_pages >> (21 - PAGE_SHIFT); | |
1da177e4 | 2178 | else |
4481374c | 2179 | limit = totalram_pages >> (23 - PAGE_SHIFT); |
1da177e4 | 2180 | |
26ff5ddc DC |
2181 | order = get_bitmask_order(limit) - 1 + PAGE_SHIFT; |
2182 | limit = (1UL << order) / sizeof(struct hlist_head); | |
2183 | order = get_bitmask_order(min(limit, (unsigned long)UINT_MAX)) - 1; | |
1da177e4 LT |
2184 | |
2185 | for (i = 0; i < MAX_LINKS; i++) { | |
2186 | struct nl_pid_hash *hash = &nl_table[i].hash; | |
2187 | ||
ea72912c | 2188 | hash->table = nl_pid_hash_zalloc(1 * sizeof(*hash->table)); |
1da177e4 LT |
2189 | if (!hash->table) { |
2190 | while (i-- > 0) | |
2191 | nl_pid_hash_free(nl_table[i].hash.table, | |
2192 | 1 * sizeof(*hash->table)); | |
2193 | kfree(nl_table); | |
fab2caf6 | 2194 | goto panic; |
1da177e4 | 2195 | } |
1da177e4 LT |
2196 | hash->max_shift = order; |
2197 | hash->shift = 0; | |
2198 | hash->mask = 0; | |
2199 | hash->rehash_time = jiffies; | |
2200 | } | |
2201 | ||
b963ea89 DM |
2202 | netlink_add_usersock_entry(); |
2203 | ||
1da177e4 | 2204 | sock_register(&netlink_family_ops); |
b4b51029 | 2205 | register_pernet_subsys(&netlink_net_ops); |
746fac4d | 2206 | /* The netlink device handler may be needed early. */ |
1da177e4 LT |
2207 | rtnetlink_init(); |
2208 | out: | |
2209 | return err; | |
fab2caf6 AM |
2210 | panic: |
2211 | panic("netlink_init: Cannot allocate nl_table\n"); | |
1da177e4 LT |
2212 | } |
2213 | ||
1da177e4 | 2214 | core_initcall(netlink_proto_init); |