blob: faa48f70b7c9b132bfaf3c8ce561982e82c4c7b6 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * NETLINK Kernel-user communication protocol.
3 *
Alan Cox113aa832008-10-13 19:01:08 -07004 * Authors: Alan Cox <alan@lxorguk.ukuu.org.uk>
Linus Torvalds1da177e2005-04-16 15:20:36 -07005 * 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.
YOSHIFUJI Hideaki746fac42007-02-09 23:25:07 +090011 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070012 * 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)
Harald Welte4fdb3bb2005-08-09 19:40:55 -070016 * 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
Linus Torvalds1da177e2005-04-16 15:20:36 -070022 */
23
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/module.h>
25
Randy Dunlap4fc268d2006-01-11 12:17:47 -080026#include <linux/capability.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <linux/kernel.h>
28#include <linux/init.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070048#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>
Andrew Morton54e0f522005-04-30 07:07:04 +010056#include <linux/audit.h>
Patrick McHardyaf65bdf2007-04-20 14:14:21 -070057#include <linux/mutex.h>
Andrew Morton54e0f522005-04-30 07:07:04 +010058
Eric W. Biederman457c4cb2007-09-12 12:01:34 +020059#include <net/net_namespace.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070060#include <net/sock.h>
61#include <net/scm.h>
Thomas Graf82ace472005-11-10 02:25:53 +010062#include <net/netlink.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070063
Patrick McHardyf7fa9b12005-08-15 12:29:13 -070064#define NLGRPSZ(x) (ALIGN(x, sizeof(unsigned long) * 8) / 8)
Johannes Bergb4ff4f02007-07-18 15:46:06 -070065#define NLGRPLONGS(x) (NLGRPSZ(x)/sizeof(unsigned long))
Linus Torvalds1da177e2005-04-16 15:20:36 -070066
67struct netlink_sock {
68 /* struct sock has to be the first member of netlink_sock */
69 struct sock sk;
70 u32 pid;
Linus Torvalds1da177e2005-04-16 15:20:36 -070071 u32 dst_pid;
Patrick McHardyd629b832005-08-14 19:27:50 -070072 u32 dst_group;
Patrick McHardyf7fa9b12005-08-15 12:29:13 -070073 u32 flags;
74 u32 subscriptions;
75 u32 ngroups;
76 unsigned long *groups;
Linus Torvalds1da177e2005-04-16 15:20:36 -070077 unsigned long state;
78 wait_queue_head_t wait;
79 struct netlink_callback *cb;
Patrick McHardyaf65bdf2007-04-20 14:14:21 -070080 struct mutex *cb_mutex;
81 struct mutex cb_def_mutex;
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -070082 void (*netlink_rcv)(struct sk_buff *skb);
Patrick McHardy77247bb2005-08-14 19:27:13 -070083 struct module *module;
Linus Torvalds1da177e2005-04-16 15:20:36 -070084};
85
Eric Dumazet5c398dc2010-10-24 04:27:10 +000086struct listeners {
87 struct rcu_head rcu;
88 unsigned long masks[0];
Johannes Berg6c04bb12009-07-10 09:51:32 +000089};
90
Patrick McHardy77247bb2005-08-14 19:27:13 -070091#define NETLINK_KERNEL_SOCKET 0x1
Patrick McHardy9a4595b2005-08-15 12:32:15 -070092#define NETLINK_RECV_PKTINFO 0x2
Pablo Neira Ayusobe0c22a2009-02-18 01:40:43 +000093#define NETLINK_BROADCAST_SEND_ERROR 0x4
Pablo Neira Ayuso38938bf2009-03-24 16:37:55 -070094#define NETLINK_RECV_NO_ENOBUFS 0x8
Patrick McHardy77247bb2005-08-14 19:27:13 -070095
Linus Torvalds1da177e2005-04-16 15:20:36 -070096static inline struct netlink_sock *nlk_sk(struct sock *sk)
97{
Denis Cheng32b21e02007-08-28 15:41:11 -070098 return container_of(sk, struct netlink_sock, sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099}
100
David S. Miller035c4c12011-12-23 17:33:03 -0500101static inline int netlink_is_kernel(struct sock *sk)
Denis V. Lunevaed81562007-10-10 21:14:32 -0700102{
103 return nlk_sk(sk)->flags & NETLINK_KERNEL_SOCKET;
104}
105
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106struct nl_pid_hash {
107 struct hlist_head *table;
108 unsigned long rehash_time;
109
110 unsigned int mask;
111 unsigned int shift;
112
113 unsigned int entries;
114 unsigned int max_shift;
115
116 u32 rnd;
117};
118
119struct netlink_table {
120 struct nl_pid_hash hash;
121 struct hlist_head mc_list;
Eric Dumazet5c398dc2010-10-24 04:27:10 +0000122 struct listeners __rcu *listeners;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123 unsigned int nl_nonroot;
Patrick McHardyf7fa9b12005-08-15 12:29:13 -0700124 unsigned int groups;
Patrick McHardyaf65bdf2007-04-20 14:14:21 -0700125 struct mutex *cb_mutex;
Patrick McHardy77247bb2005-08-14 19:27:13 -0700126 struct module *module;
Patrick McHardyab33a172005-08-14 19:31:36 -0700127 int registered;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128};
129
130static struct netlink_table *nl_table;
131
132static DECLARE_WAIT_QUEUE_HEAD(nl_table_wait);
133
134static int netlink_dump(struct sock *sk);
135static void netlink_destroy_callback(struct netlink_callback *cb);
136
137static DEFINE_RWLOCK(nl_table_lock);
138static atomic_t nl_table_users = ATOMIC_INIT(0);
139
Alan Sterne041c682006-03-27 01:16:30 -0800140static ATOMIC_NOTIFIER_HEAD(netlink_chain);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141
stephen hemmingerb57ef81f2011-12-22 08:52:02 +0000142static inline u32 netlink_group_mask(u32 group)
Patrick McHardyd629b832005-08-14 19:27:50 -0700143{
144 return group ? 1 << (group - 1) : 0;
145}
146
stephen hemmingerb57ef81f2011-12-22 08:52:02 +0000147static inline struct hlist_head *nl_pid_hashfn(struct nl_pid_hash *hash, u32 pid)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148{
149 return &hash->table[jhash_1word(pid, hash->rnd) & hash->mask];
150}
151
152static void netlink_sock_destruct(struct sock *sk)
153{
Herbert Xu3f660d62007-05-03 03:17:14 -0700154 struct netlink_sock *nlk = nlk_sk(sk);
155
Herbert Xu3f660d62007-05-03 03:17:14 -0700156 if (nlk->cb) {
157 if (nlk->cb->done)
158 nlk->cb->done(nlk->cb);
159 netlink_destroy_callback(nlk->cb);
160 }
161
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162 skb_queue_purge(&sk->sk_receive_queue);
163
164 if (!sock_flag(sk, SOCK_DEAD)) {
Patrick McHardy6ac552f2007-12-04 00:19:38 -0800165 printk(KERN_ERR "Freeing alive netlink socket %p\n", sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166 return;
167 }
Ilpo Järvinen547b7922008-07-25 21:43:18 -0700168
169 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
170 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
171 WARN_ON(nlk_sk(sk)->groups);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172}
173
Patrick McHardy6ac552f2007-12-04 00:19:38 -0800174/* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on
175 * SMP. Look, when several writers sleep and reader wakes them up, all but one
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 * immediately hit write lock and grab all the cpus. Exclusive sleep solves
177 * this, _but_ remember, it adds useless work on UP machines.
178 */
179
Johannes Bergd136f1b2009-09-12 03:03:15 +0000180void netlink_table_grab(void)
Eric Dumazet9a429c42008-01-01 21:58:02 -0800181 __acquires(nl_table_lock)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182{
Johannes Bergd136f1b2009-09-12 03:03:15 +0000183 might_sleep();
184
Arjan van de Ven6abd2192006-07-03 00:24:07 -0700185 write_lock_irq(&nl_table_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186
187 if (atomic_read(&nl_table_users)) {
188 DECLARE_WAITQUEUE(wait, current);
189
190 add_wait_queue_exclusive(&nl_table_wait, &wait);
Patrick McHardy6ac552f2007-12-04 00:19:38 -0800191 for (;;) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192 set_current_state(TASK_UNINTERRUPTIBLE);
193 if (atomic_read(&nl_table_users) == 0)
194 break;
Arjan van de Ven6abd2192006-07-03 00:24:07 -0700195 write_unlock_irq(&nl_table_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196 schedule();
Arjan van de Ven6abd2192006-07-03 00:24:07 -0700197 write_lock_irq(&nl_table_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 }
199
200 __set_current_state(TASK_RUNNING);
201 remove_wait_queue(&nl_table_wait, &wait);
202 }
203}
204
Johannes Bergd136f1b2009-09-12 03:03:15 +0000205void netlink_table_ungrab(void)
Eric Dumazet9a429c42008-01-01 21:58:02 -0800206 __releases(nl_table_lock)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207{
Arjan van de Ven6abd2192006-07-03 00:24:07 -0700208 write_unlock_irq(&nl_table_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209 wake_up(&nl_table_wait);
210}
211
Patrick McHardy6ac552f2007-12-04 00:19:38 -0800212static inline void
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213netlink_lock_table(void)
214{
215 /* read_lock() synchronizes us to netlink_table_grab */
216
217 read_lock(&nl_table_lock);
218 atomic_inc(&nl_table_users);
219 read_unlock(&nl_table_lock);
220}
221
Patrick McHardy6ac552f2007-12-04 00:19:38 -0800222static inline void
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223netlink_unlock_table(void)
224{
225 if (atomic_dec_and_test(&nl_table_users))
226 wake_up(&nl_table_wait);
227}
228
stephen hemmingerb57ef81f2011-12-22 08:52:02 +0000229static struct sock *netlink_lookup(struct net *net, int protocol, u32 pid)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230{
231 struct nl_pid_hash *hash = &nl_table[protocol].hash;
232 struct hlist_head *head;
233 struct sock *sk;
234 struct hlist_node *node;
235
236 read_lock(&nl_table_lock);
237 head = nl_pid_hashfn(hash, pid);
238 sk_for_each(sk, node, head) {
YOSHIFUJI Hideaki878628f2008-03-26 03:57:35 +0900239 if (net_eq(sock_net(sk), net) && (nlk_sk(sk)->pid == pid)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240 sock_hold(sk);
241 goto found;
242 }
243 }
244 sk = NULL;
245found:
246 read_unlock(&nl_table_lock);
247 return sk;
248}
249
stephen hemmingerb57ef81f2011-12-22 08:52:02 +0000250static struct hlist_head *nl_pid_hash_zalloc(size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251{
252 if (size <= PAGE_SIZE)
Eric Dumazetea729122007-12-11 02:09:47 -0800253 return kzalloc(size, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 else
255 return (struct hlist_head *)
Eric Dumazetea729122007-12-11 02:09:47 -0800256 __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
257 get_order(size));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258}
259
stephen hemmingerb57ef81f2011-12-22 08:52:02 +0000260static void nl_pid_hash_free(struct hlist_head *table, size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261{
262 if (size <= PAGE_SIZE)
263 kfree(table);
264 else
265 free_pages((unsigned long)table, get_order(size));
266}
267
268static int nl_pid_hash_rehash(struct nl_pid_hash *hash, int grow)
269{
270 unsigned int omask, mask, shift;
271 size_t osize, size;
272 struct hlist_head *otable, *table;
273 int i;
274
275 omask = mask = hash->mask;
276 osize = size = (mask + 1) * sizeof(*table);
277 shift = hash->shift;
278
279 if (grow) {
280 if (++shift > hash->max_shift)
281 return 0;
282 mask = mask * 2 + 1;
283 size *= 2;
284 }
285
Eric Dumazetea729122007-12-11 02:09:47 -0800286 table = nl_pid_hash_zalloc(size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 if (!table)
288 return 0;
289
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 otable = hash->table;
291 hash->table = table;
292 hash->mask = mask;
293 hash->shift = shift;
294 get_random_bytes(&hash->rnd, sizeof(hash->rnd));
295
296 for (i = 0; i <= omask; i++) {
297 struct sock *sk;
298 struct hlist_node *node, *tmp;
299
300 sk_for_each_safe(sk, node, tmp, &otable[i])
301 __sk_add_node(sk, nl_pid_hashfn(hash, nlk_sk(sk)->pid));
302 }
303
304 nl_pid_hash_free(otable, osize);
305 hash->rehash_time = jiffies + 10 * 60 * HZ;
306 return 1;
307}
308
309static inline int nl_pid_hash_dilute(struct nl_pid_hash *hash, int len)
310{
311 int avg = hash->entries >> hash->shift;
312
313 if (unlikely(avg > 1) && nl_pid_hash_rehash(hash, 1))
314 return 1;
315
316 if (unlikely(len > avg) && time_after(jiffies, hash->rehash_time)) {
317 nl_pid_hash_rehash(hash, 0);
318 return 1;
319 }
320
321 return 0;
322}
323
Eric Dumazet90ddc4f2005-12-22 12:49:22 -0800324static const struct proto_ops netlink_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325
Patrick McHardy4277a082006-03-20 18:52:01 -0800326static void
327netlink_update_listeners(struct sock *sk)
328{
329 struct netlink_table *tbl = &nl_table[sk->sk_protocol];
330 struct hlist_node *node;
331 unsigned long mask;
332 unsigned int i;
333
Johannes Bergb4ff4f02007-07-18 15:46:06 -0700334 for (i = 0; i < NLGRPLONGS(tbl->groups); i++) {
Patrick McHardy4277a082006-03-20 18:52:01 -0800335 mask = 0;
Johannes Bergb4ff4f02007-07-18 15:46:06 -0700336 sk_for_each_bound(sk, node, &tbl->mc_list) {
337 if (i < NLGRPLONGS(nlk_sk(sk)->ngroups))
338 mask |= nlk_sk(sk)->groups[i];
339 }
Eric Dumazet5c398dc2010-10-24 04:27:10 +0000340 tbl->listeners->masks[i] = mask;
Patrick McHardy4277a082006-03-20 18:52:01 -0800341 }
342 /* this function is only called with the netlink table "grabbed", which
343 * makes sure updates are visible before bind or setsockopt return. */
344}
345
Eric W. Biedermanb4b51022007-09-12 13:05:38 +0200346static int netlink_insert(struct sock *sk, struct net *net, u32 pid)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347{
348 struct nl_pid_hash *hash = &nl_table[sk->sk_protocol].hash;
349 struct hlist_head *head;
350 int err = -EADDRINUSE;
351 struct sock *osk;
352 struct hlist_node *node;
353 int len;
354
355 netlink_table_grab();
356 head = nl_pid_hashfn(hash, pid);
357 len = 0;
358 sk_for_each(osk, node, head) {
YOSHIFUJI Hideaki878628f2008-03-26 03:57:35 +0900359 if (net_eq(sock_net(osk), net) && (nlk_sk(osk)->pid == pid))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360 break;
361 len++;
362 }
363 if (node)
364 goto err;
365
366 err = -EBUSY;
367 if (nlk_sk(sk)->pid)
368 goto err;
369
370 err = -ENOMEM;
371 if (BITS_PER_LONG > 32 && unlikely(hash->entries >= UINT_MAX))
372 goto err;
373
374 if (len && nl_pid_hash_dilute(hash, len))
375 head = nl_pid_hashfn(hash, pid);
376 hash->entries++;
377 nlk_sk(sk)->pid = pid;
378 sk_add_node(sk, head);
379 err = 0;
380
381err:
382 netlink_table_ungrab();
383 return err;
384}
385
386static void netlink_remove(struct sock *sk)
387{
388 netlink_table_grab();
David S. Millerd470e3b2005-06-26 15:31:51 -0700389 if (sk_del_node_init(sk))
390 nl_table[sk->sk_protocol].hash.entries--;
Patrick McHardyf7fa9b12005-08-15 12:29:13 -0700391 if (nlk_sk(sk)->subscriptions)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392 __sk_del_bind_node(sk);
393 netlink_table_ungrab();
394}
395
396static struct proto netlink_proto = {
397 .name = "NETLINK",
398 .owner = THIS_MODULE,
399 .obj_size = sizeof(struct netlink_sock),
400};
401
Eric W. Biederman1b8d7ae2007-10-08 23:24:22 -0700402static int __netlink_create(struct net *net, struct socket *sock,
403 struct mutex *cb_mutex, int protocol)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404{
405 struct sock *sk;
406 struct netlink_sock *nlk;
Patrick McHardyab33a172005-08-14 19:31:36 -0700407
408 sock->ops = &netlink_ops;
409
Pavel Emelyanov6257ff22007-11-01 00:39:31 -0700410 sk = sk_alloc(net, PF_NETLINK, GFP_KERNEL, &netlink_proto);
Patrick McHardyab33a172005-08-14 19:31:36 -0700411 if (!sk)
412 return -ENOMEM;
413
414 sock_init_data(sock, sk);
415
416 nlk = nlk_sk(sk);
Patrick McHardyffa4d722007-04-25 14:01:17 -0700417 if (cb_mutex)
418 nlk->cb_mutex = cb_mutex;
419 else {
420 nlk->cb_mutex = &nlk->cb_def_mutex;
421 mutex_init(nlk->cb_mutex);
422 }
Patrick McHardyab33a172005-08-14 19:31:36 -0700423 init_waitqueue_head(&nlk->wait);
424
425 sk->sk_destruct = netlink_sock_destruct;
426 sk->sk_protocol = protocol;
427 return 0;
428}
429
Eric Paris3f378b62009-11-05 22:18:14 -0800430static int netlink_create(struct net *net, struct socket *sock, int protocol,
431 int kern)
Patrick McHardyab33a172005-08-14 19:31:36 -0700432{
433 struct module *module = NULL;
Patrick McHardyaf65bdf2007-04-20 14:14:21 -0700434 struct mutex *cb_mutex;
Patrick McHardyf7fa9b12005-08-15 12:29:13 -0700435 struct netlink_sock *nlk;
Patrick McHardyab33a172005-08-14 19:31:36 -0700436 int err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437
438 sock->state = SS_UNCONNECTED;
439
440 if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
441 return -ESOCKTNOSUPPORT;
442
Patrick McHardy6ac552f2007-12-04 00:19:38 -0800443 if (protocol < 0 || protocol >= MAX_LINKS)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444 return -EPROTONOSUPPORT;
445
Patrick McHardy77247bb2005-08-14 19:27:13 -0700446 netlink_lock_table();
Johannes Berg95a5afc2008-10-16 15:24:51 -0700447#ifdef CONFIG_MODULES
Patrick McHardyab33a172005-08-14 19:31:36 -0700448 if (!nl_table[protocol].registered) {
Patrick McHardy77247bb2005-08-14 19:27:13 -0700449 netlink_unlock_table();
Harald Welte4fdb3bb2005-08-09 19:40:55 -0700450 request_module("net-pf-%d-proto-%d", PF_NETLINK, protocol);
Patrick McHardy77247bb2005-08-14 19:27:13 -0700451 netlink_lock_table();
Harald Welte4fdb3bb2005-08-09 19:40:55 -0700452 }
Patrick McHardyab33a172005-08-14 19:31:36 -0700453#endif
454 if (nl_table[protocol].registered &&
455 try_module_get(nl_table[protocol].module))
456 module = nl_table[protocol].module;
Alexey Dobriyan974c37e2010-01-30 10:05:05 +0000457 else
458 err = -EPROTONOSUPPORT;
Patrick McHardyaf65bdf2007-04-20 14:14:21 -0700459 cb_mutex = nl_table[protocol].cb_mutex;
Patrick McHardy77247bb2005-08-14 19:27:13 -0700460 netlink_unlock_table();
Harald Welte4fdb3bb2005-08-09 19:40:55 -0700461
Alexey Dobriyan974c37e2010-01-30 10:05:05 +0000462 if (err < 0)
463 goto out;
464
Patrick McHardy6ac552f2007-12-04 00:19:38 -0800465 err = __netlink_create(net, sock, cb_mutex, protocol);
466 if (err < 0)
Patrick McHardyab33a172005-08-14 19:31:36 -0700467 goto out_module;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468
David S. Miller6f756a82008-11-23 17:34:03 -0800469 local_bh_disable();
Eric Dumazetc1fd3b92008-11-23 15:48:22 -0800470 sock_prot_inuse_add(net, &netlink_proto, 1);
David S. Miller6f756a82008-11-23 17:34:03 -0800471 local_bh_enable();
472
Patrick McHardyf7fa9b12005-08-15 12:29:13 -0700473 nlk = nlk_sk(sock->sk);
Patrick McHardyf7fa9b12005-08-15 12:29:13 -0700474 nlk->module = module;
Patrick McHardyab33a172005-08-14 19:31:36 -0700475out:
476 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700477
Patrick McHardyab33a172005-08-14 19:31:36 -0700478out_module:
479 module_put(module);
480 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481}
482
483static int netlink_release(struct socket *sock)
484{
485 struct sock *sk = sock->sk;
486 struct netlink_sock *nlk;
487
488 if (!sk)
489 return 0;
490
491 netlink_remove(sk);
Denis Lunevac57b3a2007-04-18 17:05:58 -0700492 sock_orphan(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493 nlk = nlk_sk(sk);
494
Herbert Xu3f660d62007-05-03 03:17:14 -0700495 /*
496 * OK. Socket is unlinked, any packets that arrive now
497 * will be purged.
498 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500 sock->sk = NULL;
501 wake_up_interruptible_all(&nlk->wait);
502
503 skb_queue_purge(&sk->sk_write_queue);
504
Johannes Berg649300b2009-11-16 12:05:34 +0000505 if (nlk->pid) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506 struct netlink_notify n = {
YOSHIFUJI Hideaki3b1e0a62008-03-26 02:26:21 +0900507 .net = sock_net(sk),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 .protocol = sk->sk_protocol,
509 .pid = nlk->pid,
510 };
Alan Sterne041c682006-03-27 01:16:30 -0800511 atomic_notifier_call_chain(&netlink_chain,
512 NETLINK_URELEASE, &n);
YOSHIFUJI Hideaki746fac42007-02-09 23:25:07 +0900513 }
Harald Welte4fdb3bb2005-08-09 19:40:55 -0700514
Mariusz Kozlowski5e7c0012007-01-02 15:24:30 -0800515 module_put(nlk->module);
Harald Welte4fdb3bb2005-08-09 19:40:55 -0700516
Patrick McHardy4277a082006-03-20 18:52:01 -0800517 netlink_table_grab();
Denis V. Lunevaed81562007-10-10 21:14:32 -0700518 if (netlink_is_kernel(sk)) {
Denis V. Lunev869e58f2008-01-18 23:53:31 -0800519 BUG_ON(nl_table[sk->sk_protocol].registered == 0);
520 if (--nl_table[sk->sk_protocol].registered == 0) {
521 kfree(nl_table[sk->sk_protocol].listeners);
522 nl_table[sk->sk_protocol].module = NULL;
523 nl_table[sk->sk_protocol].registered = 0;
524 }
Patrick McHardy4277a082006-03-20 18:52:01 -0800525 } else if (nlk->subscriptions)
526 netlink_update_listeners(sk);
527 netlink_table_ungrab();
Patrick McHardy77247bb2005-08-14 19:27:13 -0700528
Patrick McHardyf7fa9b12005-08-15 12:29:13 -0700529 kfree(nlk->groups);
530 nlk->groups = NULL;
531
Eric Dumazet37558102008-11-24 14:05:22 -0800532 local_bh_disable();
Eric Dumazetc1fd3b92008-11-23 15:48:22 -0800533 sock_prot_inuse_add(sock_net(sk), &netlink_proto, -1);
Eric Dumazet37558102008-11-24 14:05:22 -0800534 local_bh_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535 sock_put(sk);
536 return 0;
537}
538
539static int netlink_autobind(struct socket *sock)
540{
541 struct sock *sk = sock->sk;
YOSHIFUJI Hideaki3b1e0a62008-03-26 02:26:21 +0900542 struct net *net = sock_net(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543 struct nl_pid_hash *hash = &nl_table[sk->sk_protocol].hash;
544 struct hlist_head *head;
545 struct sock *osk;
546 struct hlist_node *node;
Tom Goff66aa4a52010-03-19 15:38:50 +0000547 s32 pid = task_tgid_vnr(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548 int err;
549 static s32 rover = -4097;
550
551retry:
552 cond_resched();
553 netlink_table_grab();
554 head = nl_pid_hashfn(hash, pid);
555 sk_for_each(osk, node, head) {
YOSHIFUJI Hideaki878628f2008-03-26 03:57:35 +0900556 if (!net_eq(sock_net(osk), net))
Eric W. Biedermanb4b51022007-09-12 13:05:38 +0200557 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558 if (nlk_sk(osk)->pid == pid) {
559 /* Bind collision, search negative pid values. */
560 pid = rover--;
561 if (rover > -4097)
562 rover = -4097;
563 netlink_table_ungrab();
564 goto retry;
565 }
566 }
567 netlink_table_ungrab();
568
Eric W. Biedermanb4b51022007-09-12 13:05:38 +0200569 err = netlink_insert(sk, net, pid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570 if (err == -EADDRINUSE)
571 goto retry;
David S. Millerd470e3b2005-06-26 15:31:51 -0700572
573 /* If 2 threads race to autobind, that is fine. */
574 if (err == -EBUSY)
575 err = 0;
576
577 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578}
579
stephen hemmingerb57ef81f2011-12-22 08:52:02 +0000580static inline int netlink_capable(const struct socket *sock, unsigned int flag)
YOSHIFUJI Hideaki746fac42007-02-09 23:25:07 +0900581{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700582 return (nl_table[sock->sk->sk_protocol].nl_nonroot & flag) ||
583 capable(CAP_NET_ADMIN);
YOSHIFUJI Hideaki746fac42007-02-09 23:25:07 +0900584}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585
Patrick McHardyf7fa9b12005-08-15 12:29:13 -0700586static void
587netlink_update_subscriptions(struct sock *sk, unsigned int subscriptions)
588{
589 struct netlink_sock *nlk = nlk_sk(sk);
590
591 if (nlk->subscriptions && !subscriptions)
592 __sk_del_bind_node(sk);
593 else if (!nlk->subscriptions && subscriptions)
594 sk_add_bind_node(sk, &nl_table[sk->sk_protocol].mc_list);
595 nlk->subscriptions = subscriptions;
596}
597
Johannes Bergb4ff4f02007-07-18 15:46:06 -0700598static int netlink_realloc_groups(struct sock *sk)
Patrick McHardy513c2502005-09-06 15:43:59 -0700599{
600 struct netlink_sock *nlk = nlk_sk(sk);
601 unsigned int groups;
Johannes Bergb4ff4f02007-07-18 15:46:06 -0700602 unsigned long *new_groups;
Patrick McHardy513c2502005-09-06 15:43:59 -0700603 int err = 0;
604
Johannes Bergb4ff4f02007-07-18 15:46:06 -0700605 netlink_table_grab();
606
Patrick McHardy513c2502005-09-06 15:43:59 -0700607 groups = nl_table[sk->sk_protocol].groups;
Johannes Bergb4ff4f02007-07-18 15:46:06 -0700608 if (!nl_table[sk->sk_protocol].registered) {
Patrick McHardy513c2502005-09-06 15:43:59 -0700609 err = -ENOENT;
Johannes Bergb4ff4f02007-07-18 15:46:06 -0700610 goto out_unlock;
611 }
Patrick McHardy513c2502005-09-06 15:43:59 -0700612
Johannes Bergb4ff4f02007-07-18 15:46:06 -0700613 if (nlk->ngroups >= groups)
614 goto out_unlock;
Patrick McHardy513c2502005-09-06 15:43:59 -0700615
Johannes Bergb4ff4f02007-07-18 15:46:06 -0700616 new_groups = krealloc(nlk->groups, NLGRPSZ(groups), GFP_ATOMIC);
617 if (new_groups == NULL) {
618 err = -ENOMEM;
619 goto out_unlock;
620 }
Patrick McHardy6ac552f2007-12-04 00:19:38 -0800621 memset((char *)new_groups + NLGRPSZ(nlk->ngroups), 0,
Johannes Bergb4ff4f02007-07-18 15:46:06 -0700622 NLGRPSZ(groups) - NLGRPSZ(nlk->ngroups));
623
624 nlk->groups = new_groups;
Patrick McHardy513c2502005-09-06 15:43:59 -0700625 nlk->ngroups = groups;
Johannes Bergb4ff4f02007-07-18 15:46:06 -0700626 out_unlock:
627 netlink_table_ungrab();
628 return err;
Patrick McHardy513c2502005-09-06 15:43:59 -0700629}
630
Patrick McHardy6ac552f2007-12-04 00:19:38 -0800631static int netlink_bind(struct socket *sock, struct sockaddr *addr,
632 int addr_len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633{
634 struct sock *sk = sock->sk;
YOSHIFUJI Hideaki3b1e0a62008-03-26 02:26:21 +0900635 struct net *net = sock_net(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636 struct netlink_sock *nlk = nlk_sk(sk);
637 struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr;
638 int err;
YOSHIFUJI Hideaki746fac42007-02-09 23:25:07 +0900639
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640 if (nladdr->nl_family != AF_NETLINK)
641 return -EINVAL;
642
643 /* Only superuser is allowed to listen multicasts */
Patrick McHardy513c2502005-09-06 15:43:59 -0700644 if (nladdr->nl_groups) {
645 if (!netlink_capable(sock, NL_NONROOT_RECV))
646 return -EPERM;
Johannes Bergb4ff4f02007-07-18 15:46:06 -0700647 err = netlink_realloc_groups(sk);
648 if (err)
649 return err;
Patrick McHardy513c2502005-09-06 15:43:59 -0700650 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651
652 if (nlk->pid) {
653 if (nladdr->nl_pid != nlk->pid)
654 return -EINVAL;
655 } else {
656 err = nladdr->nl_pid ?
Eric W. Biedermanb4b51022007-09-12 13:05:38 +0200657 netlink_insert(sk, net, nladdr->nl_pid) :
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658 netlink_autobind(sock);
659 if (err)
660 return err;
661 }
662
Patrick McHardy513c2502005-09-06 15:43:59 -0700663 if (!nladdr->nl_groups && (nlk->groups == NULL || !(u32)nlk->groups[0]))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664 return 0;
665
666 netlink_table_grab();
Patrick McHardyf7fa9b12005-08-15 12:29:13 -0700667 netlink_update_subscriptions(sk, nlk->subscriptions +
YOSHIFUJI Hideaki746fac42007-02-09 23:25:07 +0900668 hweight32(nladdr->nl_groups) -
669 hweight32(nlk->groups[0]));
670 nlk->groups[0] = (nlk->groups[0] & ~0xffffffffUL) | nladdr->nl_groups;
Patrick McHardy4277a082006-03-20 18:52:01 -0800671 netlink_update_listeners(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672 netlink_table_ungrab();
673
674 return 0;
675}
676
677static int netlink_connect(struct socket *sock, struct sockaddr *addr,
678 int alen, int flags)
679{
680 int err = 0;
681 struct sock *sk = sock->sk;
682 struct netlink_sock *nlk = nlk_sk(sk);
Patrick McHardy6ac552f2007-12-04 00:19:38 -0800683 struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684
Changli Gao6503d962010-03-31 22:58:26 +0000685 if (alen < sizeof(addr->sa_family))
686 return -EINVAL;
687
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688 if (addr->sa_family == AF_UNSPEC) {
689 sk->sk_state = NETLINK_UNCONNECTED;
690 nlk->dst_pid = 0;
Patrick McHardyd629b832005-08-14 19:27:50 -0700691 nlk->dst_group = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700692 return 0;
693 }
694 if (addr->sa_family != AF_NETLINK)
695 return -EINVAL;
696
697 /* Only superuser is allowed to send multicasts */
698 if (nladdr->nl_groups && !netlink_capable(sock, NL_NONROOT_SEND))
699 return -EPERM;
700
701 if (!nlk->pid)
702 err = netlink_autobind(sock);
703
704 if (err == 0) {
705 sk->sk_state = NETLINK_CONNECTED;
706 nlk->dst_pid = nladdr->nl_pid;
Patrick McHardyd629b832005-08-14 19:27:50 -0700707 nlk->dst_group = ffs(nladdr->nl_groups);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708 }
709
710 return err;
711}
712
Patrick McHardy6ac552f2007-12-04 00:19:38 -0800713static int netlink_getname(struct socket *sock, struct sockaddr *addr,
714 int *addr_len, int peer)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715{
716 struct sock *sk = sock->sk;
717 struct netlink_sock *nlk = nlk_sk(sk);
Cyrill Gorcunov13cfa972009-11-08 05:51:19 +0000718 DECLARE_SOCKADDR(struct sockaddr_nl *, nladdr, addr);
YOSHIFUJI Hideaki746fac42007-02-09 23:25:07 +0900719
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720 nladdr->nl_family = AF_NETLINK;
721 nladdr->nl_pad = 0;
722 *addr_len = sizeof(*nladdr);
723
724 if (peer) {
725 nladdr->nl_pid = nlk->dst_pid;
Patrick McHardyd629b832005-08-14 19:27:50 -0700726 nladdr->nl_groups = netlink_group_mask(nlk->dst_group);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727 } else {
728 nladdr->nl_pid = nlk->pid;
Patrick McHardy513c2502005-09-06 15:43:59 -0700729 nladdr->nl_groups = nlk->groups ? nlk->groups[0] : 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730 }
731 return 0;
732}
733
734static void netlink_overrun(struct sock *sk)
735{
Pablo Neira Ayuso38938bf2009-03-24 16:37:55 -0700736 struct netlink_sock *nlk = nlk_sk(sk);
737
738 if (!(nlk->flags & NETLINK_RECV_NO_ENOBUFS)) {
739 if (!test_and_set_bit(0, &nlk_sk(sk)->state)) {
740 sk->sk_err = ENOBUFS;
741 sk->sk_error_report(sk);
742 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743 }
Pablo Neira Ayuso38938bf2009-03-24 16:37:55 -0700744 atomic_inc(&sk->sk_drops);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745}
746
747static struct sock *netlink_getsockbypid(struct sock *ssk, u32 pid)
748{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749 struct sock *sock;
750 struct netlink_sock *nlk;
751
YOSHIFUJI Hideaki3b1e0a62008-03-26 02:26:21 +0900752 sock = netlink_lookup(sock_net(ssk), ssk->sk_protocol, pid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753 if (!sock)
754 return ERR_PTR(-ECONNREFUSED);
755
756 /* Don't bother queuing skb if kernel socket has no input function */
757 nlk = nlk_sk(sock);
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -0700758 if (sock->sk_state == NETLINK_CONNECTED &&
759 nlk->dst_pid != nlk_sk(ssk)->pid) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700760 sock_put(sock);
761 return ERR_PTR(-ECONNREFUSED);
762 }
763 return sock;
764}
765
766struct sock *netlink_getsockbyfilp(struct file *filp)
767{
Josef Sipek6db5fc52006-12-08 02:37:25 -0800768 struct inode *inode = filp->f_path.dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769 struct sock *sock;
770
771 if (!S_ISSOCK(inode->i_mode))
772 return ERR_PTR(-ENOTSOCK);
773
774 sock = SOCKET_I(inode)->sk;
775 if (sock->sk_family != AF_NETLINK)
776 return ERR_PTR(-EINVAL);
777
778 sock_hold(sock);
779 return sock;
780}
781
782/*
783 * Attach a skb to a netlink socket.
784 * The caller must hold a reference to the destination socket. On error, the
785 * reference is dropped. The skb is not send to the destination, just all
786 * all error checks are performed and memory in the queue is reserved.
787 * Return values:
788 * < 0: error. skb freed, reference to sock dropped.
789 * 0: continue
790 * 1: repeat lookup - reference dropped while waiting for socket memory.
791 */
Denis V. Lunev9457afe2008-06-05 11:23:39 -0700792int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
Patrick McHardyc3d8d1e2007-11-07 02:42:09 -0800793 long *timeo, struct sock *ssk)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794{
795 struct netlink_sock *nlk;
796
797 nlk = nlk_sk(sk);
798
799 if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
800 test_bit(0, &nlk->state)) {
801 DECLARE_WAITQUEUE(wait, current);
Patrick McHardyc3d8d1e2007-11-07 02:42:09 -0800802 if (!*timeo) {
Denis V. Lunevaed81562007-10-10 21:14:32 -0700803 if (!ssk || netlink_is_kernel(ssk))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804 netlink_overrun(sk);
805 sock_put(sk);
806 kfree_skb(skb);
807 return -EAGAIN;
808 }
809
810 __set_current_state(TASK_INTERRUPTIBLE);
811 add_wait_queue(&nlk->wait, &wait);
812
813 if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
814 test_bit(0, &nlk->state)) &&
815 !sock_flag(sk, SOCK_DEAD))
Patrick McHardyc3d8d1e2007-11-07 02:42:09 -0800816 *timeo = schedule_timeout(*timeo);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700817
818 __set_current_state(TASK_RUNNING);
819 remove_wait_queue(&nlk->wait, &wait);
820 sock_put(sk);
821
822 if (signal_pending(current)) {
823 kfree_skb(skb);
Patrick McHardyc3d8d1e2007-11-07 02:42:09 -0800824 return sock_intr_errno(*timeo);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700825 }
826 return 1;
827 }
828 skb_set_owner_r(skb, sk);
829 return 0;
830}
831
Eric Dumazet4a7e7c22012-04-05 22:17:46 +0000832static int __netlink_sendskb(struct sock *sk, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700833{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834 int len = skb->len;
835
Linus Torvalds1da177e2005-04-16 15:20:36 -0700836 skb_queue_tail(&sk->sk_receive_queue, skb);
837 sk->sk_data_ready(sk, len);
Eric Dumazet4a7e7c22012-04-05 22:17:46 +0000838 return len;
839}
840
841int netlink_sendskb(struct sock *sk, struct sk_buff *skb)
842{
843 int len = __netlink_sendskb(sk, skb);
844
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845 sock_put(sk);
846 return len;
847}
848
849void netlink_detachskb(struct sock *sk, struct sk_buff *skb)
850{
851 kfree_skb(skb);
852 sock_put(sk);
853}
854
stephen hemmingerb57ef81f2011-12-22 08:52:02 +0000855static struct sk_buff *netlink_trim(struct sk_buff *skb, gfp_t allocation)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856{
857 int delta;
858
859 skb_orphan(skb);
860
Arnaldo Carvalho de Melo4305b542007-04-19 20:43:29 -0700861 delta = skb->end - skb->tail;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862 if (delta * 2 < skb->truesize)
863 return skb;
864
865 if (skb_shared(skb)) {
866 struct sk_buff *nskb = skb_clone(skb, allocation);
867 if (!nskb)
868 return skb;
869 kfree_skb(skb);
870 skb = nskb;
871 }
872
873 if (!pskb_expand_head(skb, 0, -delta, allocation))
874 skb->truesize -= delta;
875
876 return skb;
877}
878
stephen hemmingerb57ef81f2011-12-22 08:52:02 +0000879static void netlink_rcv_wake(struct sock *sk)
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -0700880{
881 struct netlink_sock *nlk = nlk_sk(sk);
882
883 if (skb_queue_empty(&sk->sk_receive_queue))
884 clear_bit(0, &nlk->state);
885 if (!test_bit(0, &nlk->state))
886 wake_up_interruptible(&nlk->wait);
887}
888
stephen hemmingerb57ef81f2011-12-22 08:52:02 +0000889static int netlink_unicast_kernel(struct sock *sk, struct sk_buff *skb)
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -0700890{
891 int ret;
892 struct netlink_sock *nlk = nlk_sk(sk);
893
894 ret = -ECONNREFUSED;
895 if (nlk->netlink_rcv != NULL) {
896 ret = skb->len;
897 skb_set_owner_r(skb, sk);
898 nlk->netlink_rcv(skb);
899 }
900 kfree_skb(skb);
901 sock_put(sk);
902 return ret;
903}
904
905int netlink_unicast(struct sock *ssk, struct sk_buff *skb,
906 u32 pid, int nonblock)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700907{
908 struct sock *sk;
909 int err;
910 long timeo;
911
912 skb = netlink_trim(skb, gfp_any());
913
914 timeo = sock_sndtimeo(ssk, nonblock);
915retry:
916 sk = netlink_getsockbypid(ssk, pid);
917 if (IS_ERR(sk)) {
918 kfree_skb(skb);
919 return PTR_ERR(sk);
920 }
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -0700921 if (netlink_is_kernel(sk))
922 return netlink_unicast_kernel(sk, skb);
923
Stephen Hemmingerb1153f22008-03-21 15:46:12 -0700924 if (sk_filter(sk, skb)) {
Wang Chen84874602008-07-01 19:55:09 -0700925 err = skb->len;
Stephen Hemmingerb1153f22008-03-21 15:46:12 -0700926 kfree_skb(skb);
927 sock_put(sk);
928 return err;
929 }
930
Denis V. Lunev9457afe2008-06-05 11:23:39 -0700931 err = netlink_attachskb(sk, skb, &timeo, ssk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700932 if (err == 1)
933 goto retry;
934 if (err)
935 return err;
936
Denis V. Lunev7ee015e2007-10-10 21:14:03 -0700937 return netlink_sendskb(sk, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938}
Patrick McHardy6ac552f2007-12-04 00:19:38 -0800939EXPORT_SYMBOL(netlink_unicast);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700940
Patrick McHardy4277a082006-03-20 18:52:01 -0800941int netlink_has_listeners(struct sock *sk, unsigned int group)
942{
943 int res = 0;
Eric Dumazet5c398dc2010-10-24 04:27:10 +0000944 struct listeners *listeners;
Patrick McHardy4277a082006-03-20 18:52:01 -0800945
Denis V. Lunevaed81562007-10-10 21:14:32 -0700946 BUG_ON(!netlink_is_kernel(sk));
Johannes Bergb4ff4f02007-07-18 15:46:06 -0700947
948 rcu_read_lock();
949 listeners = rcu_dereference(nl_table[sk->sk_protocol].listeners);
950
Patrick McHardy4277a082006-03-20 18:52:01 -0800951 if (group - 1 < nl_table[sk->sk_protocol].groups)
Eric Dumazet5c398dc2010-10-24 04:27:10 +0000952 res = test_bit(group - 1, listeners->masks);
Johannes Bergb4ff4f02007-07-18 15:46:06 -0700953
954 rcu_read_unlock();
955
Patrick McHardy4277a082006-03-20 18:52:01 -0800956 return res;
957}
958EXPORT_SYMBOL_GPL(netlink_has_listeners);
959
stephen hemmingerb57ef81f2011-12-22 08:52:02 +0000960static int netlink_broadcast_deliver(struct sock *sk, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700961{
962 struct netlink_sock *nlk = nlk_sk(sk);
963
964 if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf &&
965 !test_bit(0, &nlk->state)) {
966 skb_set_owner_r(skb, sk);
Eric Dumazet4a7e7c22012-04-05 22:17:46 +0000967 __netlink_sendskb(sk, skb);
stephen hemminger2c6458002011-12-22 08:52:03 +0000968 return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700969 }
970 return -1;
971}
972
973struct netlink_broadcast_data {
974 struct sock *exclude_sk;
Eric W. Biedermanb4b51022007-09-12 13:05:38 +0200975 struct net *net;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700976 u32 pid;
977 u32 group;
978 int failure;
Pablo Neira Ayusoff491a72009-02-05 23:56:36 -0800979 int delivery_failure;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980 int congested;
981 int delivered;
Al Viro7d877f32005-10-21 03:20:43 -0400982 gfp_t allocation;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700983 struct sk_buff *skb, *skb2;
Eric W. Biederman910a7e92010-05-04 17:36:46 -0700984 int (*tx_filter)(struct sock *dsk, struct sk_buff *skb, void *data);
985 void *tx_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700986};
987
stephen hemmingerb57ef81f2011-12-22 08:52:02 +0000988static int do_one_broadcast(struct sock *sk,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700989 struct netlink_broadcast_data *p)
990{
991 struct netlink_sock *nlk = nlk_sk(sk);
992 int val;
993
994 if (p->exclude_sk == sk)
995 goto out;
996
Patrick McHardyf7fa9b12005-08-15 12:29:13 -0700997 if (nlk->pid == p->pid || p->group - 1 >= nlk->ngroups ||
998 !test_bit(p->group - 1, nlk->groups))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700999 goto out;
1000
YOSHIFUJI Hideaki878628f2008-03-26 03:57:35 +09001001 if (!net_eq(sock_net(sk), p->net))
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02001002 goto out;
1003
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004 if (p->failure) {
1005 netlink_overrun(sk);
1006 goto out;
1007 }
1008
1009 sock_hold(sk);
1010 if (p->skb2 == NULL) {
Tommy S. Christensen68acc022005-05-19 13:06:35 -07001011 if (skb_shared(p->skb)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001012 p->skb2 = skb_clone(p->skb, p->allocation);
1013 } else {
Tommy S. Christensen68acc022005-05-19 13:06:35 -07001014 p->skb2 = skb_get(p->skb);
1015 /*
1016 * skb ownership may have been set when
1017 * delivered to a previous socket.
1018 */
1019 skb_orphan(p->skb2);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001020 }
1021 }
1022 if (p->skb2 == NULL) {
1023 netlink_overrun(sk);
1024 /* Clone failed. Notify ALL listeners. */
1025 p->failure = 1;
Pablo Neira Ayusobe0c22a2009-02-18 01:40:43 +00001026 if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR)
1027 p->delivery_failure = 1;
Eric W. Biederman910a7e92010-05-04 17:36:46 -07001028 } else if (p->tx_filter && p->tx_filter(sk, p->skb2, p->tx_data)) {
1029 kfree_skb(p->skb2);
1030 p->skb2 = NULL;
Stephen Hemmingerb1153f22008-03-21 15:46:12 -07001031 } else if (sk_filter(sk, p->skb2)) {
1032 kfree_skb(p->skb2);
1033 p->skb2 = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001034 } else if ((val = netlink_broadcast_deliver(sk, p->skb2)) < 0) {
1035 netlink_overrun(sk);
Pablo Neira Ayusobe0c22a2009-02-18 01:40:43 +00001036 if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR)
1037 p->delivery_failure = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001038 } else {
1039 p->congested |= val;
1040 p->delivered = 1;
1041 p->skb2 = NULL;
1042 }
1043 sock_put(sk);
1044
1045out:
1046 return 0;
1047}
1048
Eric W. Biederman910a7e92010-05-04 17:36:46 -07001049int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb, u32 pid,
1050 u32 group, gfp_t allocation,
1051 int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data),
1052 void *filter_data)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053{
YOSHIFUJI Hideaki3b1e0a62008-03-26 02:26:21 +09001054 struct net *net = sock_net(ssk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001055 struct netlink_broadcast_data info;
1056 struct hlist_node *node;
1057 struct sock *sk;
1058
1059 skb = netlink_trim(skb, allocation);
1060
1061 info.exclude_sk = ssk;
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02001062 info.net = net;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001063 info.pid = pid;
1064 info.group = group;
1065 info.failure = 0;
Pablo Neira Ayusoff491a72009-02-05 23:56:36 -08001066 info.delivery_failure = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001067 info.congested = 0;
1068 info.delivered = 0;
1069 info.allocation = allocation;
1070 info.skb = skb;
1071 info.skb2 = NULL;
Eric W. Biederman910a7e92010-05-04 17:36:46 -07001072 info.tx_filter = filter;
1073 info.tx_data = filter_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001074
1075 /* While we sleep in clone, do not allow to change socket list */
1076
1077 netlink_lock_table();
1078
1079 sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list)
1080 do_one_broadcast(sk, &info);
1081
Neil Horman70d4bf62010-07-20 06:45:56 +00001082 consume_skb(skb);
Tommy S. Christensenaa1c6a62005-05-19 13:07:32 -07001083
Linus Torvalds1da177e2005-04-16 15:20:36 -07001084 netlink_unlock_table();
1085
Neil Horman70d4bf62010-07-20 06:45:56 +00001086 if (info.delivery_failure) {
1087 kfree_skb(info.skb2);
Pablo Neira Ayusoff491a72009-02-05 23:56:36 -08001088 return -ENOBUFS;
Neil Horman70d4bf62010-07-20 06:45:56 +00001089 } else
1090 consume_skb(info.skb2);
Pablo Neira Ayusoff491a72009-02-05 23:56:36 -08001091
Linus Torvalds1da177e2005-04-16 15:20:36 -07001092 if (info.delivered) {
1093 if (info.congested && (allocation & __GFP_WAIT))
1094 yield();
1095 return 0;
1096 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001097 return -ESRCH;
1098}
Eric W. Biederman910a7e92010-05-04 17:36:46 -07001099EXPORT_SYMBOL(netlink_broadcast_filtered);
1100
1101int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 pid,
1102 u32 group, gfp_t allocation)
1103{
1104 return netlink_broadcast_filtered(ssk, skb, pid, group, allocation,
1105 NULL, NULL);
1106}
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001107EXPORT_SYMBOL(netlink_broadcast);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001108
1109struct netlink_set_err_data {
1110 struct sock *exclude_sk;
1111 u32 pid;
1112 u32 group;
1113 int code;
1114};
1115
stephen hemmingerb57ef81f2011-12-22 08:52:02 +00001116static int do_one_set_err(struct sock *sk, struct netlink_set_err_data *p)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001117{
1118 struct netlink_sock *nlk = nlk_sk(sk);
Pablo Neira Ayuso1a503072010-03-18 14:24:42 +00001119 int ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001120
1121 if (sk == p->exclude_sk)
1122 goto out;
1123
Octavian Purdila09ad9bc2009-11-25 15:14:13 -08001124 if (!net_eq(sock_net(sk), sock_net(p->exclude_sk)))
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02001125 goto out;
1126
Patrick McHardyf7fa9b12005-08-15 12:29:13 -07001127 if (nlk->pid == p->pid || p->group - 1 >= nlk->ngroups ||
1128 !test_bit(p->group - 1, nlk->groups))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001129 goto out;
1130
Pablo Neira Ayuso1a503072010-03-18 14:24:42 +00001131 if (p->code == ENOBUFS && nlk->flags & NETLINK_RECV_NO_ENOBUFS) {
1132 ret = 1;
1133 goto out;
1134 }
1135
Linus Torvalds1da177e2005-04-16 15:20:36 -07001136 sk->sk_err = p->code;
1137 sk->sk_error_report(sk);
1138out:
Pablo Neira Ayuso1a503072010-03-18 14:24:42 +00001139 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001140}
1141
Pablo Neira Ayuso4843b932009-03-03 23:37:30 -08001142/**
1143 * netlink_set_err - report error to broadcast listeners
1144 * @ssk: the kernel netlink socket, as returned by netlink_kernel_create()
1145 * @pid: the PID of a process that we want to skip (if any)
1146 * @groups: the broadcast group that will notice the error
1147 * @code: error code, must be negative (as usual in kernelspace)
Pablo Neira Ayuso1a503072010-03-18 14:24:42 +00001148 *
1149 * This function returns the number of broadcast listeners that have set the
1150 * NETLINK_RECV_NO_ENOBUFS socket option.
Pablo Neira Ayuso4843b932009-03-03 23:37:30 -08001151 */
Pablo Neira Ayuso1a503072010-03-18 14:24:42 +00001152int netlink_set_err(struct sock *ssk, u32 pid, u32 group, int code)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001153{
1154 struct netlink_set_err_data info;
1155 struct hlist_node *node;
1156 struct sock *sk;
Pablo Neira Ayuso1a503072010-03-18 14:24:42 +00001157 int ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001158
1159 info.exclude_sk = ssk;
1160 info.pid = pid;
1161 info.group = group;
Pablo Neira Ayuso4843b932009-03-03 23:37:30 -08001162 /* sk->sk_err wants a positive error value */
1163 info.code = -code;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001164
1165 read_lock(&nl_table_lock);
1166
1167 sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list)
Pablo Neira Ayuso1a503072010-03-18 14:24:42 +00001168 ret += do_one_set_err(sk, &info);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001169
1170 read_unlock(&nl_table_lock);
Pablo Neira Ayuso1a503072010-03-18 14:24:42 +00001171 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001172}
Pablo Neira Ayusodd5b6ce2009-03-23 13:21:06 +01001173EXPORT_SYMBOL(netlink_set_err);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001174
Johannes Berg84659eb2007-07-18 15:47:05 -07001175/* must be called with netlink table grabbed */
1176static void netlink_update_socket_mc(struct netlink_sock *nlk,
1177 unsigned int group,
1178 int is_new)
1179{
1180 int old, new = !!is_new, subscriptions;
1181
1182 old = test_bit(group - 1, nlk->groups);
1183 subscriptions = nlk->subscriptions - old + new;
1184 if (new)
1185 __set_bit(group - 1, nlk->groups);
1186 else
1187 __clear_bit(group - 1, nlk->groups);
1188 netlink_update_subscriptions(&nlk->sk, subscriptions);
1189 netlink_update_listeners(&nlk->sk);
1190}
1191
Patrick McHardy9a4595b2005-08-15 12:32:15 -07001192static int netlink_setsockopt(struct socket *sock, int level, int optname,
David S. Millerb7058842009-09-30 16:12:20 -07001193 char __user *optval, unsigned int optlen)
Patrick McHardy9a4595b2005-08-15 12:32:15 -07001194{
1195 struct sock *sk = sock->sk;
1196 struct netlink_sock *nlk = nlk_sk(sk);
Johannes Bergeb496532007-07-18 02:07:51 -07001197 unsigned int val = 0;
1198 int err;
Patrick McHardy9a4595b2005-08-15 12:32:15 -07001199
1200 if (level != SOL_NETLINK)
1201 return -ENOPROTOOPT;
1202
1203 if (optlen >= sizeof(int) &&
Johannes Bergeb496532007-07-18 02:07:51 -07001204 get_user(val, (unsigned int __user *)optval))
Patrick McHardy9a4595b2005-08-15 12:32:15 -07001205 return -EFAULT;
1206
1207 switch (optname) {
1208 case NETLINK_PKTINFO:
1209 if (val)
1210 nlk->flags |= NETLINK_RECV_PKTINFO;
1211 else
1212 nlk->flags &= ~NETLINK_RECV_PKTINFO;
1213 err = 0;
1214 break;
1215 case NETLINK_ADD_MEMBERSHIP:
1216 case NETLINK_DROP_MEMBERSHIP: {
Patrick McHardy9a4595b2005-08-15 12:32:15 -07001217 if (!netlink_capable(sock, NL_NONROOT_RECV))
1218 return -EPERM;
Johannes Bergb4ff4f02007-07-18 15:46:06 -07001219 err = netlink_realloc_groups(sk);
1220 if (err)
1221 return err;
Patrick McHardy9a4595b2005-08-15 12:32:15 -07001222 if (!val || val - 1 >= nlk->ngroups)
1223 return -EINVAL;
1224 netlink_table_grab();
Johannes Berg84659eb2007-07-18 15:47:05 -07001225 netlink_update_socket_mc(nlk, val,
1226 optname == NETLINK_ADD_MEMBERSHIP);
Patrick McHardy9a4595b2005-08-15 12:32:15 -07001227 netlink_table_ungrab();
1228 err = 0;
1229 break;
1230 }
Pablo Neira Ayusobe0c22a2009-02-18 01:40:43 +00001231 case NETLINK_BROADCAST_ERROR:
1232 if (val)
1233 nlk->flags |= NETLINK_BROADCAST_SEND_ERROR;
1234 else
1235 nlk->flags &= ~NETLINK_BROADCAST_SEND_ERROR;
1236 err = 0;
1237 break;
Pablo Neira Ayuso38938bf2009-03-24 16:37:55 -07001238 case NETLINK_NO_ENOBUFS:
1239 if (val) {
1240 nlk->flags |= NETLINK_RECV_NO_ENOBUFS;
1241 clear_bit(0, &nlk->state);
1242 wake_up_interruptible(&nlk->wait);
1243 } else
1244 nlk->flags &= ~NETLINK_RECV_NO_ENOBUFS;
1245 err = 0;
1246 break;
Patrick McHardy9a4595b2005-08-15 12:32:15 -07001247 default:
1248 err = -ENOPROTOOPT;
1249 }
1250 return err;
1251}
1252
1253static int netlink_getsockopt(struct socket *sock, int level, int optname,
YOSHIFUJI Hideaki746fac42007-02-09 23:25:07 +09001254 char __user *optval, int __user *optlen)
Patrick McHardy9a4595b2005-08-15 12:32:15 -07001255{
1256 struct sock *sk = sock->sk;
1257 struct netlink_sock *nlk = nlk_sk(sk);
1258 int len, val, err;
1259
1260 if (level != SOL_NETLINK)
1261 return -ENOPROTOOPT;
1262
1263 if (get_user(len, optlen))
1264 return -EFAULT;
1265 if (len < 0)
1266 return -EINVAL;
1267
1268 switch (optname) {
1269 case NETLINK_PKTINFO:
1270 if (len < sizeof(int))
1271 return -EINVAL;
1272 len = sizeof(int);
1273 val = nlk->flags & NETLINK_RECV_PKTINFO ? 1 : 0;
Heiko Carstensa27b58f2006-10-30 15:06:12 -08001274 if (put_user(len, optlen) ||
1275 put_user(val, optval))
1276 return -EFAULT;
Patrick McHardy9a4595b2005-08-15 12:32:15 -07001277 err = 0;
1278 break;
Pablo Neira Ayusobe0c22a2009-02-18 01:40:43 +00001279 case NETLINK_BROADCAST_ERROR:
1280 if (len < sizeof(int))
1281 return -EINVAL;
1282 len = sizeof(int);
1283 val = nlk->flags & NETLINK_BROADCAST_SEND_ERROR ? 1 : 0;
1284 if (put_user(len, optlen) ||
1285 put_user(val, optval))
1286 return -EFAULT;
1287 err = 0;
1288 break;
Pablo Neira Ayuso38938bf2009-03-24 16:37:55 -07001289 case NETLINK_NO_ENOBUFS:
1290 if (len < sizeof(int))
1291 return -EINVAL;
1292 len = sizeof(int);
1293 val = nlk->flags & NETLINK_RECV_NO_ENOBUFS ? 1 : 0;
1294 if (put_user(len, optlen) ||
1295 put_user(val, optval))
1296 return -EFAULT;
1297 err = 0;
1298 break;
Patrick McHardy9a4595b2005-08-15 12:32:15 -07001299 default:
1300 err = -ENOPROTOOPT;
1301 }
1302 return err;
1303}
1304
1305static void netlink_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
1306{
1307 struct nl_pktinfo info;
1308
1309 info.group = NETLINK_CB(skb).dst_group;
1310 put_cmsg(msg, SOL_NETLINK, NETLINK_PKTINFO, sizeof(info), &info);
1311}
1312
Linus Torvalds1da177e2005-04-16 15:20:36 -07001313static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
1314 struct msghdr *msg, size_t len)
1315{
1316 struct sock_iocb *siocb = kiocb_to_siocb(kiocb);
1317 struct sock *sk = sock->sk;
1318 struct netlink_sock *nlk = nlk_sk(sk);
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001319 struct sockaddr_nl *addr = msg->msg_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001320 u32 dst_pid;
Patrick McHardyd629b832005-08-14 19:27:50 -07001321 u32 dst_group;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001322 struct sk_buff *skb;
1323 int err;
1324 struct scm_cookie scm;
1325
1326 if (msg->msg_flags&MSG_OOB)
1327 return -EOPNOTSUPP;
1328
Eric Dumazet16e57262011-09-19 05:52:27 +00001329 if (NULL == siocb->scm)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001330 siocb->scm = &scm;
Eric Dumazet16e57262011-09-19 05:52:27 +00001331
Linus Torvalds1da177e2005-04-16 15:20:36 -07001332 err = scm_send(sock, msg, siocb->scm);
1333 if (err < 0)
1334 return err;
1335
1336 if (msg->msg_namelen) {
Eric W. Biedermanb47030c2010-06-13 03:31:06 +00001337 err = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001338 if (addr->nl_family != AF_NETLINK)
Eric W. Biedermanb47030c2010-06-13 03:31:06 +00001339 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001340 dst_pid = addr->nl_pid;
Patrick McHardyd629b832005-08-14 19:27:50 -07001341 dst_group = ffs(addr->nl_groups);
Eric W. Biedermanb47030c2010-06-13 03:31:06 +00001342 err = -EPERM;
Patrick McHardyd629b832005-08-14 19:27:50 -07001343 if (dst_group && !netlink_capable(sock, NL_NONROOT_SEND))
Eric W. Biedermanb47030c2010-06-13 03:31:06 +00001344 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001345 } else {
1346 dst_pid = nlk->dst_pid;
Patrick McHardyd629b832005-08-14 19:27:50 -07001347 dst_group = nlk->dst_group;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001348 }
1349
1350 if (!nlk->pid) {
1351 err = netlink_autobind(sock);
1352 if (err)
1353 goto out;
1354 }
1355
1356 err = -EMSGSIZE;
1357 if (len > sk->sk_sndbuf - 32)
1358 goto out;
1359 err = -ENOBUFS;
Thomas Graf339bf982006-11-10 14:10:15 -08001360 skb = alloc_skb(len, GFP_KERNEL);
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001361 if (skb == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001362 goto out;
1363
1364 NETLINK_CB(skb).pid = nlk->pid;
Patrick McHardyd629b832005-08-14 19:27:50 -07001365 NETLINK_CB(skb).dst_group = dst_group;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001366 memcpy(NETLINK_CREDS(skb), &siocb->scm->creds, sizeof(struct ucred));
1367
Linus Torvalds1da177e2005-04-16 15:20:36 -07001368 err = -EFAULT;
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001369 if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001370 kfree_skb(skb);
1371 goto out;
1372 }
1373
1374 err = security_netlink_send(sk, skb);
1375 if (err) {
1376 kfree_skb(skb);
1377 goto out;
1378 }
1379
Patrick McHardyd629b832005-08-14 19:27:50 -07001380 if (dst_group) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001381 atomic_inc(&skb->users);
Patrick McHardyd629b832005-08-14 19:27:50 -07001382 netlink_broadcast(sk, skb, dst_pid, dst_group, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001383 }
1384 err = netlink_unicast(sk, skb, dst_pid, msg->msg_flags&MSG_DONTWAIT);
1385
1386out:
Eric W. Biedermanb47030c2010-06-13 03:31:06 +00001387 scm_destroy(siocb->scm);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001388 return err;
1389}
1390
1391static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
1392 struct msghdr *msg, size_t len,
1393 int flags)
1394{
1395 struct sock_iocb *siocb = kiocb_to_siocb(kiocb);
1396 struct scm_cookie scm;
1397 struct sock *sk = sock->sk;
1398 struct netlink_sock *nlk = nlk_sk(sk);
1399 int noblock = flags&MSG_DONTWAIT;
1400 size_t copied;
Johannes Berg68d6ac62010-08-15 21:20:44 +00001401 struct sk_buff *skb, *data_skb;
Andrey Vaginb44d2112011-02-21 02:40:47 +00001402 int err, ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001403
1404 if (flags&MSG_OOB)
1405 return -EOPNOTSUPP;
1406
1407 copied = 0;
1408
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001409 skb = skb_recv_datagram(sk, flags, noblock, &err);
1410 if (skb == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001411 goto out;
1412
Johannes Berg68d6ac62010-08-15 21:20:44 +00001413 data_skb = skb;
1414
Johannes Berg1dacc762009-07-01 11:26:02 +00001415#ifdef CONFIG_COMPAT_NETLINK_MESSAGES
1416 if (unlikely(skb_shinfo(skb)->frag_list)) {
Johannes Berg1dacc762009-07-01 11:26:02 +00001417 /*
Johannes Berg68d6ac62010-08-15 21:20:44 +00001418 * If this skb has a frag_list, then here that means that we
1419 * will have to use the frag_list skb's data for compat tasks
1420 * and the regular skb's data for normal (non-compat) tasks.
Johannes Berg1dacc762009-07-01 11:26:02 +00001421 *
Johannes Berg68d6ac62010-08-15 21:20:44 +00001422 * If we need to send the compat skb, assign it to the
1423 * 'data_skb' variable so that it will be used below for data
1424 * copying. We keep 'skb' for everything else, including
1425 * freeing both later.
Johannes Berg1dacc762009-07-01 11:26:02 +00001426 */
Johannes Berg68d6ac62010-08-15 21:20:44 +00001427 if (flags & MSG_CMSG_COMPAT)
1428 data_skb = skb_shinfo(skb)->frag_list;
Johannes Berg1dacc762009-07-01 11:26:02 +00001429 }
1430#endif
1431
Linus Torvalds1da177e2005-04-16 15:20:36 -07001432 msg->msg_namelen = 0;
1433
Johannes Berg68d6ac62010-08-15 21:20:44 +00001434 copied = data_skb->len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001435 if (len < copied) {
1436 msg->msg_flags |= MSG_TRUNC;
1437 copied = len;
1438 }
1439
Johannes Berg68d6ac62010-08-15 21:20:44 +00001440 skb_reset_transport_header(data_skb);
1441 err = skb_copy_datagram_iovec(data_skb, 0, msg->msg_iov, copied);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001442
1443 if (msg->msg_name) {
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001444 struct sockaddr_nl *addr = (struct sockaddr_nl *)msg->msg_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001445 addr->nl_family = AF_NETLINK;
1446 addr->nl_pad = 0;
1447 addr->nl_pid = NETLINK_CB(skb).pid;
Patrick McHardyd629b832005-08-14 19:27:50 -07001448 addr->nl_groups = netlink_group_mask(NETLINK_CB(skb).dst_group);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001449 msg->msg_namelen = sizeof(*addr);
1450 }
1451
Patrick McHardycc9a06c2006-03-12 20:34:27 -08001452 if (nlk->flags & NETLINK_RECV_PKTINFO)
1453 netlink_cmsg_recv_pktinfo(msg, skb);
1454
Linus Torvalds1da177e2005-04-16 15:20:36 -07001455 if (NULL == siocb->scm) {
1456 memset(&scm, 0, sizeof(scm));
1457 siocb->scm = &scm;
1458 }
1459 siocb->scm->creds = *NETLINK_CREDS(skb);
Patrick McHardy188ccb52007-05-03 03:27:01 -07001460 if (flags & MSG_TRUNC)
Johannes Berg68d6ac62010-08-15 21:20:44 +00001461 copied = data_skb->len;
David S. Millerdaa37662010-08-15 23:21:50 -07001462
Linus Torvalds1da177e2005-04-16 15:20:36 -07001463 skb_free_datagram(sk, skb);
1464
Andrey Vaginb44d2112011-02-21 02:40:47 +00001465 if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) {
1466 ret = netlink_dump(sk);
1467 if (ret) {
1468 sk->sk_err = ret;
1469 sk->sk_error_report(sk);
1470 }
1471 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001472
1473 scm_recv(sock, msg, siocb->scm, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001474out:
1475 netlink_rcv_wake(sk);
1476 return err ? : copied;
1477}
1478
1479static void netlink_data_ready(struct sock *sk, int len)
1480{
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -07001481 BUG();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001482}
1483
1484/*
YOSHIFUJI Hideaki746fac42007-02-09 23:25:07 +09001485 * We export these functions to other modules. They provide a
Linus Torvalds1da177e2005-04-16 15:20:36 -07001486 * complete set of kernel non-blocking support for message
1487 * queueing.
1488 */
1489
1490struct sock *
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02001491netlink_kernel_create(struct net *net, int unit, unsigned int groups,
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -07001492 void (*input)(struct sk_buff *skb),
Patrick McHardyaf65bdf2007-04-20 14:14:21 -07001493 struct mutex *cb_mutex, struct module *module)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001494{
1495 struct socket *sock;
1496 struct sock *sk;
Patrick McHardy77247bb2005-08-14 19:27:13 -07001497 struct netlink_sock *nlk;
Eric Dumazet5c398dc2010-10-24 04:27:10 +00001498 struct listeners *listeners = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001499
Akinobu Mitafab2caf2006-08-29 02:15:24 -07001500 BUG_ON(!nl_table);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001501
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001502 if (unit < 0 || unit >= MAX_LINKS)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001503 return NULL;
1504
1505 if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock))
1506 return NULL;
1507
Pavel Emelyanov23fe1862008-01-30 19:31:06 -08001508 /*
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;
Denis V. Lunevedf02082008-02-29 11:18:32 -08001518 sk_change_net(sk, net);
Harald Welte4fdb3bb2005-08-09 19:40:55 -07001519
Patrick McHardy4277a082006-03-20 18:52:01 -08001520 if (groups < 32)
1521 groups = 32;
1522
Eric Dumazet5c398dc2010-10-24 04:27:10 +00001523 listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL);
Patrick McHardy4277a082006-03-20 18:52:01 -08001524 if (!listeners)
1525 goto out_sock_release;
1526
Linus Torvalds1da177e2005-04-16 15:20:36 -07001527 sk->sk_data_ready = netlink_data_ready;
1528 if (input)
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -07001529 nlk_sk(sk)->netlink_rcv = input;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001530
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02001531 if (netlink_insert(sk, net, 0))
Patrick McHardy77247bb2005-08-14 19:27:13 -07001532 goto out_sock_release;
1533
1534 nlk = nlk_sk(sk);
1535 nlk->flags |= NETLINK_KERNEL_SOCKET;
1536
1537 netlink_table_grab();
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02001538 if (!nl_table[unit].registered) {
1539 nl_table[unit].groups = groups;
Eric Dumazet5c398dc2010-10-24 04:27:10 +00001540 rcu_assign_pointer(nl_table[unit].listeners, listeners);
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02001541 nl_table[unit].cb_mutex = cb_mutex;
1542 nl_table[unit].module = module;
1543 nl_table[unit].registered = 1;
Jesper Juhlf937f1f462007-10-15 01:39:12 -07001544 } else {
1545 kfree(listeners);
Denis V. Lunev869e58f2008-01-18 23:53:31 -08001546 nl_table[unit].registered++;
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02001547 }
Patrick McHardy77247bb2005-08-14 19:27:13 -07001548 netlink_table_ungrab();
Harald Welte4fdb3bb2005-08-09 19:40:55 -07001549 return sk;
1550
Harald Welte4fdb3bb2005-08-09 19:40:55 -07001551out_sock_release:
Patrick McHardy4277a082006-03-20 18:52:01 -08001552 kfree(listeners);
Denis V. Lunev9dfbec12008-02-29 11:17:56 -08001553 netlink_kernel_release(sk);
Pavel Emelyanov23fe1862008-01-30 19:31:06 -08001554 return NULL;
1555
1556out_sock_release_nosk:
Harald Welte4fdb3bb2005-08-09 19:40:55 -07001557 sock_release(sock);
Patrick McHardy77247bb2005-08-14 19:27:13 -07001558 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001559}
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001560EXPORT_SYMBOL(netlink_kernel_create);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001561
Denis V. Lunevb7c6ba62008-01-28 14:41:19 -08001562
1563void
1564netlink_kernel_release(struct sock *sk)
1565{
Denis V. Lunevedf02082008-02-29 11:18:32 -08001566 sk_release_kernel(sk);
Denis V. Lunevb7c6ba62008-01-28 14:41:19 -08001567}
1568EXPORT_SYMBOL(netlink_kernel_release);
1569
Johannes Bergd136f1b2009-09-12 03:03:15 +00001570int __netlink_change_ngroups(struct sock *sk, unsigned int groups)
Johannes Bergb4ff4f02007-07-18 15:46:06 -07001571{
Eric Dumazet5c398dc2010-10-24 04:27:10 +00001572 struct listeners *new, *old;
Johannes Bergb4ff4f02007-07-18 15:46:06 -07001573 struct netlink_table *tbl = &nl_table[sk->sk_protocol];
Johannes Bergb4ff4f02007-07-18 15:46:06 -07001574
1575 if (groups < 32)
1576 groups = 32;
1577
Johannes Bergb4ff4f02007-07-18 15:46:06 -07001578 if (NLGRPSZ(tbl->groups) < NLGRPSZ(groups)) {
Eric Dumazet5c398dc2010-10-24 04:27:10 +00001579 new = kzalloc(sizeof(*new) + NLGRPSZ(groups), GFP_ATOMIC);
1580 if (!new)
Johannes Bergd136f1b2009-09-12 03:03:15 +00001581 return -ENOMEM;
Eric Dumazet33d480c2011-08-11 19:30:52 +00001582 old = rcu_dereference_protected(tbl->listeners, 1);
Eric Dumazet5c398dc2010-10-24 04:27:10 +00001583 memcpy(new->masks, old->masks, NLGRPSZ(tbl->groups));
1584 rcu_assign_pointer(tbl->listeners, new);
1585
Lai Jiangshan37b6b932011-03-15 18:01:42 +08001586 kfree_rcu(old, rcu);
Johannes Bergb4ff4f02007-07-18 15:46:06 -07001587 }
1588 tbl->groups = groups;
1589
Johannes Bergd136f1b2009-09-12 03:03:15 +00001590 return 0;
1591}
1592
1593/**
1594 * netlink_change_ngroups - change number of multicast groups
1595 *
1596 * This changes the number of multicast groups that are available
1597 * on a certain netlink family. Note that it is not possible to
1598 * change the number of groups to below 32. Also note that it does
1599 * not implicitly call netlink_clear_multicast_users() when the
1600 * number of groups is reduced.
1601 *
1602 * @sk: The kernel netlink socket, as returned by netlink_kernel_create().
1603 * @groups: The new number of groups.
1604 */
1605int netlink_change_ngroups(struct sock *sk, unsigned int groups)
1606{
1607 int err;
1608
1609 netlink_table_grab();
1610 err = __netlink_change_ngroups(sk, groups);
Johannes Bergb4ff4f02007-07-18 15:46:06 -07001611 netlink_table_ungrab();
Johannes Bergd136f1b2009-09-12 03:03:15 +00001612
Johannes Bergb4ff4f02007-07-18 15:46:06 -07001613 return err;
1614}
Johannes Bergb4ff4f02007-07-18 15:46:06 -07001615
Johannes Bergb8273572009-09-24 15:44:05 -07001616void __netlink_clear_multicast_users(struct sock *ksk, unsigned int group)
1617{
1618 struct sock *sk;
1619 struct hlist_node *node;
1620 struct netlink_table *tbl = &nl_table[ksk->sk_protocol];
1621
1622 sk_for_each_bound(sk, node, &tbl->mc_list)
1623 netlink_update_socket_mc(nlk_sk(sk), group, 0);
1624}
1625
Johannes Berg84659eb2007-07-18 15:47:05 -07001626/**
1627 * netlink_clear_multicast_users - kick off multicast listeners
1628 *
1629 * This function removes all listeners from the given group.
1630 * @ksk: The kernel netlink socket, as returned by
1631 * netlink_kernel_create().
1632 * @group: The multicast group to clear.
1633 */
1634void netlink_clear_multicast_users(struct sock *ksk, unsigned int group)
1635{
Johannes Berg84659eb2007-07-18 15:47:05 -07001636 netlink_table_grab();
Johannes Bergb8273572009-09-24 15:44:05 -07001637 __netlink_clear_multicast_users(ksk, group);
Johannes Berg84659eb2007-07-18 15:47:05 -07001638 netlink_table_ungrab();
1639}
Johannes Berg84659eb2007-07-18 15:47:05 -07001640
Linus Torvalds1da177e2005-04-16 15:20:36 -07001641void netlink_set_nonroot(int protocol, unsigned int flags)
YOSHIFUJI Hideaki746fac42007-02-09 23:25:07 +09001642{
1643 if ((unsigned int)protocol < MAX_LINKS)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001644 nl_table[protocol].nl_nonroot = flags;
YOSHIFUJI Hideaki746fac42007-02-09 23:25:07 +09001645}
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001646EXPORT_SYMBOL(netlink_set_nonroot);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001647
1648static void netlink_destroy_callback(struct netlink_callback *cb)
1649{
Wei Yongjun91744f62009-02-25 00:34:41 +00001650 kfree_skb(cb->skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001651 kfree(cb);
1652}
1653
Denys Vlasenkoa46621a2012-01-30 15:22:06 -05001654struct nlmsghdr *
1655__nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags)
1656{
1657 struct nlmsghdr *nlh;
1658 int size = NLMSG_LENGTH(len);
1659
1660 nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size));
1661 nlh->nlmsg_type = type;
1662 nlh->nlmsg_len = size;
1663 nlh->nlmsg_flags = flags;
1664 nlh->nlmsg_pid = pid;
1665 nlh->nlmsg_seq = seq;
1666 if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0)
1667 memset(NLMSG_DATA(nlh) + len, 0, NLMSG_ALIGN(size) - size);
1668 return nlh;
1669}
1670EXPORT_SYMBOL(__nlmsg_put);
1671
Linus Torvalds1da177e2005-04-16 15:20:36 -07001672/*
1673 * It looks a bit ugly.
1674 * It would be better to create kernel thread.
1675 */
1676
1677static int netlink_dump(struct sock *sk)
1678{
1679 struct netlink_sock *nlk = nlk_sk(sk);
1680 struct netlink_callback *cb;
Greg Rosec7ac8672011-06-10 01:27:09 +00001681 struct sk_buff *skb = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001682 struct nlmsghdr *nlh;
Thomas Grafbf8b79e2006-08-04 23:03:29 -07001683 int len, err = -ENOBUFS;
Greg Rosec7ac8672011-06-10 01:27:09 +00001684 int alloc_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001685
Patrick McHardyaf65bdf2007-04-20 14:14:21 -07001686 mutex_lock(nlk->cb_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001687
1688 cb = nlk->cb;
1689 if (cb == NULL) {
Thomas Grafbf8b79e2006-08-04 23:03:29 -07001690 err = -EINVAL;
1691 goto errout_skb;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001692 }
1693
Greg Rosec7ac8672011-06-10 01:27:09 +00001694 alloc_size = max_t(int, cb->min_dump_alloc, NLMSG_GOODSIZE);
1695
1696 skb = sock_rmalloc(sk, alloc_size, 0, GFP_KERNEL);
1697 if (!skb)
Dan Carpenterc63d6ea2011-06-15 03:11:42 +00001698 goto errout_skb;
Greg Rosec7ac8672011-06-10 01:27:09 +00001699
Linus Torvalds1da177e2005-04-16 15:20:36 -07001700 len = cb->dump(skb, cb);
1701
1702 if (len > 0) {
Patrick McHardyaf65bdf2007-04-20 14:14:21 -07001703 mutex_unlock(nlk->cb_mutex);
Stephen Hemmingerb1153f22008-03-21 15:46:12 -07001704
1705 if (sk_filter(sk, skb))
1706 kfree_skb(skb);
Eric Dumazet4a7e7c22012-04-05 22:17:46 +00001707 else
1708 __netlink_sendskb(sk, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001709 return 0;
1710 }
1711
Thomas Grafbf8b79e2006-08-04 23:03:29 -07001712 nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI);
1713 if (!nlh)
1714 goto errout_skb;
1715
Johannes Berg670dc282011-06-20 13:40:46 +02001716 nl_dump_check_consistent(cb, nlh);
1717
Thomas Grafbf8b79e2006-08-04 23:03:29 -07001718 memcpy(nlmsg_data(nlh), &len, sizeof(len));
1719
Stephen Hemmingerb1153f22008-03-21 15:46:12 -07001720 if (sk_filter(sk, skb))
1721 kfree_skb(skb);
Eric Dumazet4a7e7c22012-04-05 22:17:46 +00001722 else
1723 __netlink_sendskb(sk, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001724
Thomas Grafa8f74b22005-11-10 02:25:52 +01001725 if (cb->done)
1726 cb->done(cb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001727 nlk->cb = NULL;
Patrick McHardyaf65bdf2007-04-20 14:14:21 -07001728 mutex_unlock(nlk->cb_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001729
1730 netlink_destroy_callback(cb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001731 return 0;
Thomas Graf17977542005-06-18 22:53:48 -07001732
Thomas Grafbf8b79e2006-08-04 23:03:29 -07001733errout_skb:
Patrick McHardyaf65bdf2007-04-20 14:14:21 -07001734 mutex_unlock(nlk->cb_mutex);
Thomas Grafbf8b79e2006-08-04 23:03:29 -07001735 kfree_skb(skb);
Thomas Grafbf8b79e2006-08-04 23:03:29 -07001736 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001737}
1738
1739int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
Patrick McHardy3a6c2b42009-08-25 16:07:40 +02001740 const struct nlmsghdr *nlh,
Pablo Neira Ayuso80d326f2012-02-24 14:30:15 +00001741 struct netlink_dump_control *control)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001742{
1743 struct netlink_callback *cb;
1744 struct sock *sk;
1745 struct netlink_sock *nlk;
Andrey Vaginb44d2112011-02-21 02:40:47 +00001746 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001747
Panagiotis Issaris0da974f2006-07-21 14:51:30 -07001748 cb = kzalloc(sizeof(*cb), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001749 if (cb == NULL)
1750 return -ENOBUFS;
1751
Pablo Neira Ayuso80d326f2012-02-24 14:30:15 +00001752 cb->dump = control->dump;
1753 cb->done = control->done;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001754 cb->nlh = nlh;
Pablo Neira Ayuso7175c882012-02-24 14:30:16 +00001755 cb->data = control->data;
Pablo Neira Ayuso80d326f2012-02-24 14:30:15 +00001756 cb->min_dump_alloc = control->min_dump_alloc;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001757 atomic_inc(&skb->users);
1758 cb->skb = skb;
1759
YOSHIFUJI Hideaki3b1e0a62008-03-26 02:26:21 +09001760 sk = netlink_lookup(sock_net(ssk), ssk->sk_protocol, NETLINK_CB(skb).pid);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001761 if (sk == NULL) {
1762 netlink_destroy_callback(cb);
1763 return -ECONNREFUSED;
1764 }
1765 nlk = nlk_sk(sk);
Herbert Xu3f660d62007-05-03 03:17:14 -07001766 /* A dump is in progress... */
Patrick McHardyaf65bdf2007-04-20 14:14:21 -07001767 mutex_lock(nlk->cb_mutex);
Herbert Xu3f660d62007-05-03 03:17:14 -07001768 if (nlk->cb) {
Patrick McHardyaf65bdf2007-04-20 14:14:21 -07001769 mutex_unlock(nlk->cb_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001770 netlink_destroy_callback(cb);
1771 sock_put(sk);
1772 return -EBUSY;
1773 }
1774 nlk->cb = cb;
Patrick McHardyaf65bdf2007-04-20 14:14:21 -07001775 mutex_unlock(nlk->cb_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001776
Andrey Vaginb44d2112011-02-21 02:40:47 +00001777 ret = netlink_dump(sk);
1778
Linus Torvalds1da177e2005-04-16 15:20:36 -07001779 sock_put(sk);
Denis V. Lunev5c582982007-10-23 20:29:25 -07001780
Andrey Vaginb44d2112011-02-21 02:40:47 +00001781 if (ret)
1782 return ret;
1783
Denis V. Lunev5c582982007-10-23 20:29:25 -07001784 /* We successfully started a dump, by returning -EINTR we
1785 * signal not to send ACK even if it was requested.
1786 */
1787 return -EINTR;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001788}
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001789EXPORT_SYMBOL(netlink_dump_start);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001790
1791void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err)
1792{
1793 struct sk_buff *skb;
1794 struct nlmsghdr *rep;
1795 struct nlmsgerr *errmsg;
Thomas Graf339bf982006-11-10 14:10:15 -08001796 size_t payload = sizeof(*errmsg);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001797
Thomas Graf339bf982006-11-10 14:10:15 -08001798 /* error messages get the original request appened */
1799 if (err)
1800 payload += nlmsg_len(nlh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001801
Thomas Graf339bf982006-11-10 14:10:15 -08001802 skb = nlmsg_new(payload, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001803 if (!skb) {
1804 struct sock *sk;
1805
YOSHIFUJI Hideaki3b1e0a62008-03-26 02:26:21 +09001806 sk = netlink_lookup(sock_net(in_skb->sk),
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02001807 in_skb->sk->sk_protocol,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001808 NETLINK_CB(in_skb).pid);
1809 if (sk) {
1810 sk->sk_err = ENOBUFS;
1811 sk->sk_error_report(sk);
1812 sock_put(sk);
1813 }
1814 return;
1815 }
1816
1817 rep = __nlmsg_put(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
John Fastabend5dba93a2009-09-25 13:11:44 +00001818 NLMSG_ERROR, payload, 0);
Thomas Grafbf8b79e2006-08-04 23:03:29 -07001819 errmsg = nlmsg_data(rep);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001820 errmsg->error = err;
Thomas Grafbf8b79e2006-08-04 23:03:29 -07001821 memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(*nlh));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001822 netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).pid, MSG_DONTWAIT);
1823}
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001824EXPORT_SYMBOL(netlink_ack);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001825
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -07001826int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *,
Thomas Graf1d00a4e2007-03-22 23:30:12 -07001827 struct nlmsghdr *))
Thomas Graf82ace472005-11-10 02:25:53 +01001828{
Thomas Graf82ace472005-11-10 02:25:53 +01001829 struct nlmsghdr *nlh;
1830 int err;
1831
1832 while (skb->len >= nlmsg_total_size(0)) {
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -07001833 int msglen;
1834
Arnaldo Carvalho de Melob529ccf2007-04-25 19:08:35 -07001835 nlh = nlmsg_hdr(skb);
Thomas Grafd35b6852007-03-22 23:28:46 -07001836 err = 0;
Thomas Graf82ace472005-11-10 02:25:53 +01001837
Martin Murrayad8e4b72006-01-10 13:02:29 -08001838 if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len)
Thomas Graf82ace472005-11-10 02:25:53 +01001839 return 0;
1840
Thomas Grafd35b6852007-03-22 23:28:46 -07001841 /* Only requests are handled by the kernel */
1842 if (!(nlh->nlmsg_flags & NLM_F_REQUEST))
Denis V. Lunev5c582982007-10-23 20:29:25 -07001843 goto ack;
Thomas Grafd35b6852007-03-22 23:28:46 -07001844
Thomas Graf45e7ae72007-03-22 23:29:10 -07001845 /* Skip control messages */
1846 if (nlh->nlmsg_type < NLMSG_MIN_TYPE)
Denis V. Lunev5c582982007-10-23 20:29:25 -07001847 goto ack;
Thomas Graf45e7ae72007-03-22 23:29:10 -07001848
Thomas Graf1d00a4e2007-03-22 23:30:12 -07001849 err = cb(skb, nlh);
Denis V. Lunev5c582982007-10-23 20:29:25 -07001850 if (err == -EINTR)
1851 goto skip;
1852
1853ack:
Thomas Grafd35b6852007-03-22 23:28:46 -07001854 if (nlh->nlmsg_flags & NLM_F_ACK || err)
Thomas Graf82ace472005-11-10 02:25:53 +01001855 netlink_ack(skb, nlh, err);
Thomas Graf82ace472005-11-10 02:25:53 +01001856
Denis V. Lunev5c582982007-10-23 20:29:25 -07001857skip:
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001858 msglen = NLMSG_ALIGN(nlh->nlmsg_len);
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -07001859 if (msglen > skb->len)
1860 msglen = skb->len;
1861 skb_pull(skb, msglen);
Thomas Graf82ace472005-11-10 02:25:53 +01001862 }
1863
1864 return 0;
1865}
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001866EXPORT_SYMBOL(netlink_rcv_skb);
Thomas Graf82ace472005-11-10 02:25:53 +01001867
1868/**
Thomas Grafd387f6a2006-08-15 00:31:06 -07001869 * nlmsg_notify - send a notification netlink message
1870 * @sk: netlink socket to use
1871 * @skb: notification message
1872 * @pid: destination netlink pid for reports or 0
1873 * @group: destination multicast group or 0
1874 * @report: 1 to report back, 0 to disable
1875 * @flags: allocation flags
1876 */
1877int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 pid,
1878 unsigned int group, int report, gfp_t flags)
1879{
1880 int err = 0;
1881
1882 if (group) {
1883 int exclude_pid = 0;
1884
1885 if (report) {
1886 atomic_inc(&skb->users);
1887 exclude_pid = pid;
1888 }
1889
Pablo Neira Ayuso1ce85fe2009-02-24 23:18:28 -08001890 /* errors reported via destination sk->sk_err, but propagate
1891 * delivery errors if NETLINK_BROADCAST_ERROR flag is set */
1892 err = nlmsg_multicast(sk, skb, exclude_pid, group, flags);
Thomas Grafd387f6a2006-08-15 00:31:06 -07001893 }
1894
Pablo Neira Ayuso1ce85fe2009-02-24 23:18:28 -08001895 if (report) {
1896 int err2;
1897
1898 err2 = nlmsg_unicast(sk, skb, pid);
1899 if (!err || err == -ESRCH)
1900 err = err2;
1901 }
Thomas Grafd387f6a2006-08-15 00:31:06 -07001902
1903 return err;
1904}
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001905EXPORT_SYMBOL(nlmsg_notify);
Thomas Grafd387f6a2006-08-15 00:31:06 -07001906
Linus Torvalds1da177e2005-04-16 15:20:36 -07001907#ifdef CONFIG_PROC_FS
1908struct nl_seq_iter {
Denis V. Luneve372c412007-11-19 22:31:54 -08001909 struct seq_net_private p;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001910 int link;
1911 int hash_idx;
1912};
1913
1914static struct sock *netlink_seq_socket_idx(struct seq_file *seq, loff_t pos)
1915{
1916 struct nl_seq_iter *iter = seq->private;
1917 int i, j;
1918 struct sock *s;
1919 struct hlist_node *node;
1920 loff_t off = 0;
1921
Patrick McHardy6ac552f2007-12-04 00:19:38 -08001922 for (i = 0; i < MAX_LINKS; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001923 struct nl_pid_hash *hash = &nl_table[i].hash;
1924
1925 for (j = 0; j <= hash->mask; j++) {
1926 sk_for_each(s, node, &hash->table[j]) {
YOSHIFUJI Hideaki12188542008-03-26 02:36:06 +09001927 if (sock_net(s) != seq_file_net(seq))
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02001928 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001929 if (off == pos) {
1930 iter->link = i;
1931 iter->hash_idx = j;
1932 return s;
1933 }
1934 ++off;
1935 }
1936 }
1937 }
1938 return NULL;
1939}
1940
1941static void *netlink_seq_start(struct seq_file *seq, loff_t *pos)
Eric Dumazet9a429c42008-01-01 21:58:02 -08001942 __acquires(nl_table_lock)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001943{
1944 read_lock(&nl_table_lock);
1945 return *pos ? netlink_seq_socket_idx(seq, *pos - 1) : SEQ_START_TOKEN;
1946}
1947
1948static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1949{
1950 struct sock *s;
1951 struct nl_seq_iter *iter;
1952 int i, j;
1953
1954 ++*pos;
1955
1956 if (v == SEQ_START_TOKEN)
1957 return netlink_seq_socket_idx(seq, 0);
YOSHIFUJI Hideaki746fac42007-02-09 23:25:07 +09001958
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02001959 iter = seq->private;
1960 s = v;
1961 do {
1962 s = sk_next(s);
YOSHIFUJI Hideaki12188542008-03-26 02:36:06 +09001963 } while (s && sock_net(s) != seq_file_net(seq));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001964 if (s)
1965 return s;
1966
Linus Torvalds1da177e2005-04-16 15:20:36 -07001967 i = iter->link;
1968 j = iter->hash_idx + 1;
1969
1970 do {
1971 struct nl_pid_hash *hash = &nl_table[i].hash;
1972
1973 for (; j <= hash->mask; j++) {
1974 s = sk_head(&hash->table[j]);
YOSHIFUJI Hideaki12188542008-03-26 02:36:06 +09001975 while (s && sock_net(s) != seq_file_net(seq))
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02001976 s = sk_next(s);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001977 if (s) {
1978 iter->link = i;
1979 iter->hash_idx = j;
1980 return s;
1981 }
1982 }
1983
1984 j = 0;
1985 } while (++i < MAX_LINKS);
1986
1987 return NULL;
1988}
1989
1990static void netlink_seq_stop(struct seq_file *seq, void *v)
Eric Dumazet9a429c42008-01-01 21:58:02 -08001991 __releases(nl_table_lock)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001992{
1993 read_unlock(&nl_table_lock);
1994}
1995
1996
1997static int netlink_seq_show(struct seq_file *seq, void *v)
1998{
1999 if (v == SEQ_START_TOKEN)
2000 seq_puts(seq,
2001 "sk Eth Pid Groups "
Masatake YAMATOcf0aa4e2010-02-27 19:45:37 +00002002 "Rmem Wmem Dump Locks Drops Inode\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07002003 else {
2004 struct sock *s = v;
2005 struct netlink_sock *nlk = nlk_sk(s);
2006
Dan Rosenberg71338aa2011-05-23 12:17:35 +00002007 seq_printf(seq, "%pK %-3d %-6d %08x %-8d %-8d %pK %-8d %-8d %-8lu\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07002008 s,
2009 s->sk_protocol,
2010 nlk->pid,
Patrick McHardy513c2502005-09-06 15:43:59 -07002011 nlk->groups ? (u32)nlk->groups[0] : 0,
Eric Dumazet31e6d362009-06-17 19:05:41 -07002012 sk_rmem_alloc_get(s),
2013 sk_wmem_alloc_get(s),
Linus Torvalds1da177e2005-04-16 15:20:36 -07002014 nlk->cb,
Pablo Neira Ayuso38938bf2009-03-24 16:37:55 -07002015 atomic_read(&s->sk_refcnt),
Masatake YAMATOcf0aa4e2010-02-27 19:45:37 +00002016 atomic_read(&s->sk_drops),
2017 sock_i_ino(s)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002018 );
2019
2020 }
2021 return 0;
2022}
2023
Philippe De Muyter56b3d972007-07-10 23:07:31 -07002024static const struct seq_operations netlink_seq_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002025 .start = netlink_seq_start,
2026 .next = netlink_seq_next,
2027 .stop = netlink_seq_stop,
2028 .show = netlink_seq_show,
2029};
2030
2031
2032static int netlink_seq_open(struct inode *inode, struct file *file)
2033{
Denis V. Luneve372c412007-11-19 22:31:54 -08002034 return seq_open_net(inode, file, &netlink_seq_ops,
2035 sizeof(struct nl_seq_iter));
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02002036}
2037
Arjan van de Venda7071d2007-02-12 00:55:36 -08002038static const struct file_operations netlink_seq_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002039 .owner = THIS_MODULE,
2040 .open = netlink_seq_open,
2041 .read = seq_read,
2042 .llseek = seq_lseek,
Denis V. Luneve372c412007-11-19 22:31:54 -08002043 .release = seq_release_net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002044};
2045
2046#endif
2047
2048int netlink_register_notifier(struct notifier_block *nb)
2049{
Alan Sterne041c682006-03-27 01:16:30 -08002050 return atomic_notifier_chain_register(&netlink_chain, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002051}
Patrick McHardy6ac552f2007-12-04 00:19:38 -08002052EXPORT_SYMBOL(netlink_register_notifier);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002053
2054int netlink_unregister_notifier(struct notifier_block *nb)
2055{
Alan Sterne041c682006-03-27 01:16:30 -08002056 return atomic_notifier_chain_unregister(&netlink_chain, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002057}
Patrick McHardy6ac552f2007-12-04 00:19:38 -08002058EXPORT_SYMBOL(netlink_unregister_notifier);
YOSHIFUJI Hideaki746fac42007-02-09 23:25:07 +09002059
Eric Dumazet90ddc4f2005-12-22 12:49:22 -08002060static const struct proto_ops netlink_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002061 .family = PF_NETLINK,
2062 .owner = THIS_MODULE,
2063 .release = netlink_release,
2064 .bind = netlink_bind,
2065 .connect = netlink_connect,
2066 .socketpair = sock_no_socketpair,
2067 .accept = sock_no_accept,
2068 .getname = netlink_getname,
2069 .poll = datagram_poll,
2070 .ioctl = sock_no_ioctl,
2071 .listen = sock_no_listen,
2072 .shutdown = sock_no_shutdown,
Patrick McHardy9a4595b2005-08-15 12:32:15 -07002073 .setsockopt = netlink_setsockopt,
2074 .getsockopt = netlink_getsockopt,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002075 .sendmsg = netlink_sendmsg,
2076 .recvmsg = netlink_recvmsg,
2077 .mmap = sock_no_mmap,
2078 .sendpage = sock_no_sendpage,
2079};
2080
Stephen Hemmingerec1b4cf2009-10-05 05:58:39 +00002081static const struct net_proto_family netlink_family_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002082 .family = PF_NETLINK,
2083 .create = netlink_create,
2084 .owner = THIS_MODULE, /* for consistency 8) */
2085};
2086
Pavel Emelyanov46650792007-10-08 20:38:39 -07002087static int __net_init netlink_net_init(struct net *net)
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02002088{
2089#ifdef CONFIG_PROC_FS
2090 if (!proc_net_fops_create(net, "netlink", 0, &netlink_seq_fops))
2091 return -ENOMEM;
2092#endif
2093 return 0;
2094}
2095
Pavel Emelyanov46650792007-10-08 20:38:39 -07002096static void __net_exit netlink_net_exit(struct net *net)
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02002097{
2098#ifdef CONFIG_PROC_FS
2099 proc_net_remove(net, "netlink");
2100#endif
2101}
2102
David S. Millerb963ea82010-08-30 19:08:01 -07002103static void __init netlink_add_usersock_entry(void)
2104{
Eric Dumazet5c398dc2010-10-24 04:27:10 +00002105 struct listeners *listeners;
David S. Millerb963ea82010-08-30 19:08:01 -07002106 int groups = 32;
2107
Eric Dumazet5c398dc2010-10-24 04:27:10 +00002108 listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL);
David S. Millerb963ea82010-08-30 19:08:01 -07002109 if (!listeners)
Eric Dumazet5c398dc2010-10-24 04:27:10 +00002110 panic("netlink_add_usersock_entry: Cannot allocate listeners\n");
David S. Millerb963ea82010-08-30 19:08:01 -07002111
2112 netlink_table_grab();
2113
2114 nl_table[NETLINK_USERSOCK].groups = groups;
Eric Dumazet5c398dc2010-10-24 04:27:10 +00002115 rcu_assign_pointer(nl_table[NETLINK_USERSOCK].listeners, listeners);
David S. Millerb963ea82010-08-30 19:08:01 -07002116 nl_table[NETLINK_USERSOCK].module = THIS_MODULE;
2117 nl_table[NETLINK_USERSOCK].registered = 1;
2118
2119 netlink_table_ungrab();
2120}
2121
Denis V. Lunev022cbae2007-11-13 03:23:50 -08002122static struct pernet_operations __net_initdata netlink_net_ops = {
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02002123 .init = netlink_net_init,
2124 .exit = netlink_net_exit,
2125};
2126
Linus Torvalds1da177e2005-04-16 15:20:36 -07002127static int __init netlink_proto_init(void)
2128{
2129 struct sk_buff *dummy_skb;
2130 int i;
Denis Cheng26ff5dd2007-09-16 16:36:02 -07002131 unsigned long limit;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002132 unsigned int order;
2133 int err = proto_register(&netlink_proto, 0);
2134
2135 if (err != 0)
2136 goto out;
2137
YOSHIFUJI Hideakief047f52006-09-01 00:29:06 -07002138 BUILD_BUG_ON(sizeof(struct netlink_skb_parms) > sizeof(dummy_skb->cb));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002139
Panagiotis Issaris0da974f2006-07-21 14:51:30 -07002140 nl_table = kcalloc(MAX_LINKS, sizeof(*nl_table), GFP_KERNEL);
Akinobu Mitafab2caf2006-08-29 02:15:24 -07002141 if (!nl_table)
2142 goto panic;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002143
Jan Beulich44813742009-09-21 17:03:05 -07002144 if (totalram_pages >= (128 * 1024))
2145 limit = totalram_pages >> (21 - PAGE_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002146 else
Jan Beulich44813742009-09-21 17:03:05 -07002147 limit = totalram_pages >> (23 - PAGE_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002148
Denis Cheng26ff5dd2007-09-16 16:36:02 -07002149 order = get_bitmask_order(limit) - 1 + PAGE_SHIFT;
2150 limit = (1UL << order) / sizeof(struct hlist_head);
2151 order = get_bitmask_order(min(limit, (unsigned long)UINT_MAX)) - 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002152
2153 for (i = 0; i < MAX_LINKS; i++) {
2154 struct nl_pid_hash *hash = &nl_table[i].hash;
2155
Eric Dumazetea729122007-12-11 02:09:47 -08002156 hash->table = nl_pid_hash_zalloc(1 * sizeof(*hash->table));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002157 if (!hash->table) {
2158 while (i-- > 0)
2159 nl_pid_hash_free(nl_table[i].hash.table,
2160 1 * sizeof(*hash->table));
2161 kfree(nl_table);
Akinobu Mitafab2caf2006-08-29 02:15:24 -07002162 goto panic;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002163 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002164 hash->max_shift = order;
2165 hash->shift = 0;
2166 hash->mask = 0;
2167 hash->rehash_time = jiffies;
2168 }
2169
David S. Millerb963ea82010-08-30 19:08:01 -07002170 netlink_add_usersock_entry();
2171
Linus Torvalds1da177e2005-04-16 15:20:36 -07002172 sock_register(&netlink_family_ops);
Eric W. Biedermanb4b51022007-09-12 13:05:38 +02002173 register_pernet_subsys(&netlink_net_ops);
YOSHIFUJI Hideaki746fac42007-02-09 23:25:07 +09002174 /* The netlink device handler may be needed early. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002175 rtnetlink_init();
2176out:
2177 return err;
Akinobu Mitafab2caf2006-08-29 02:15:24 -07002178panic:
2179 panic("netlink_init: Cannot allocate nl_table\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07002180}
2181
Linus Torvalds1da177e2005-04-16 15:20:36 -07002182core_initcall(netlink_proto_init);