2 * NETLINK Kernel-user communication protocol.
4 * Authors: Alan Cox <alan@redhat.com>
5 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
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.
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)
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
24 #include <linux/module.h>
26 #include <linux/capability.h>
27 #include <linux/kernel.h>
28 #include <linux/init.h>
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>
36 #include <linux/fcntl.h>
37 #include <linux/termios.h>
38 #include <linux/sockios.h>
39 #include <linux/net.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>
48 #include <linux/smp_lock.h>
49 #include <linux/notifier.h>
50 #include <linux/security.h>
51 #include <linux/jhash.h>
52 #include <linux/jiffies.h>
53 #include <linux/random.h>
54 #include <linux/bitops.h>
56 #include <linux/types.h>
57 #include <linux/audit.h>
58 #include <linux/selinux.h>
62 #include <net/netlink.h>
64 #define NLGRPSZ(x) (ALIGN(x, sizeof(unsigned long) * 8) / 8)
67 /* struct sock has to be the first member of netlink_sock */
75 unsigned long *groups
;
77 wait_queue_head_t wait
;
78 struct netlink_callback
*cb
;
80 void (*data_ready
)(struct sock
*sk
, int bytes
);
81 struct module
*module
;
84 #define NETLINK_KERNEL_SOCKET 0x1
85 #define NETLINK_RECV_PKTINFO 0x2
87 static inline struct netlink_sock
*nlk_sk(struct sock
*sk
)
89 return (struct netlink_sock
*)sk
;
93 struct hlist_head
*table
;
94 unsigned long rehash_time
;
100 unsigned int max_shift
;
105 struct netlink_table
{
106 struct nl_pid_hash hash
;
107 struct hlist_head mc_list
;
108 unsigned long *listeners
;
109 unsigned int nl_nonroot
;
111 struct module
*module
;
115 static struct netlink_table
*nl_table
;
117 static DECLARE_WAIT_QUEUE_HEAD(nl_table_wait
);
119 static int netlink_dump(struct sock
*sk
);
120 static void netlink_destroy_callback(struct netlink_callback
*cb
);
122 static DEFINE_RWLOCK(nl_table_lock
);
123 static atomic_t nl_table_users
= ATOMIC_INIT(0);
125 static ATOMIC_NOTIFIER_HEAD(netlink_chain
);
127 static u32
netlink_group_mask(u32 group
)
129 return group
? 1 << (group
- 1) : 0;
132 static struct hlist_head
*nl_pid_hashfn(struct nl_pid_hash
*hash
, u32 pid
)
134 return &hash
->table
[jhash_1word(pid
, hash
->rnd
) & hash
->mask
];
137 static void netlink_sock_destruct(struct sock
*sk
)
139 skb_queue_purge(&sk
->sk_receive_queue
);
141 if (!sock_flag(sk
, SOCK_DEAD
)) {
142 printk("Freeing alive netlink socket %p\n", sk
);
145 BUG_TRAP(!atomic_read(&sk
->sk_rmem_alloc
));
146 BUG_TRAP(!atomic_read(&sk
->sk_wmem_alloc
));
147 BUG_TRAP(!nlk_sk(sk
)->cb
);
148 BUG_TRAP(!nlk_sk(sk
)->groups
);
151 /* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on SMP.
152 * Look, when several writers sleep and reader wakes them up, all but one
153 * immediately hit write lock and grab all the cpus. Exclusive sleep solves
154 * this, _but_ remember, it adds useless work on UP machines.
157 static void netlink_table_grab(void)
159 write_lock_irq(&nl_table_lock
);
161 if (atomic_read(&nl_table_users
)) {
162 DECLARE_WAITQUEUE(wait
, current
);
164 add_wait_queue_exclusive(&nl_table_wait
, &wait
);
166 set_current_state(TASK_UNINTERRUPTIBLE
);
167 if (atomic_read(&nl_table_users
) == 0)
169 write_unlock_irq(&nl_table_lock
);
171 write_lock_irq(&nl_table_lock
);
174 __set_current_state(TASK_RUNNING
);
175 remove_wait_queue(&nl_table_wait
, &wait
);
179 static __inline__
void netlink_table_ungrab(void)
181 write_unlock_irq(&nl_table_lock
);
182 wake_up(&nl_table_wait
);
185 static __inline__
void
186 netlink_lock_table(void)
188 /* read_lock() synchronizes us to netlink_table_grab */
190 read_lock(&nl_table_lock
);
191 atomic_inc(&nl_table_users
);
192 read_unlock(&nl_table_lock
);
195 static __inline__
void
196 netlink_unlock_table(void)
198 if (atomic_dec_and_test(&nl_table_users
))
199 wake_up(&nl_table_wait
);
202 static __inline__
struct sock
*netlink_lookup(int protocol
, u32 pid
)
204 struct nl_pid_hash
*hash
= &nl_table
[protocol
].hash
;
205 struct hlist_head
*head
;
207 struct hlist_node
*node
;
209 read_lock(&nl_table_lock
);
210 head
= nl_pid_hashfn(hash
, pid
);
211 sk_for_each(sk
, node
, head
) {
212 if (nlk_sk(sk
)->pid
== pid
) {
219 read_unlock(&nl_table_lock
);
223 static inline struct hlist_head
*nl_pid_hash_alloc(size_t size
)
225 if (size
<= PAGE_SIZE
)
226 return kmalloc(size
, GFP_ATOMIC
);
228 return (struct hlist_head
*)
229 __get_free_pages(GFP_ATOMIC
, get_order(size
));
232 static inline void nl_pid_hash_free(struct hlist_head
*table
, size_t size
)
234 if (size
<= PAGE_SIZE
)
237 free_pages((unsigned long)table
, get_order(size
));
240 static int nl_pid_hash_rehash(struct nl_pid_hash
*hash
, int grow
)
242 unsigned int omask
, mask
, shift
;
244 struct hlist_head
*otable
, *table
;
247 omask
= mask
= hash
->mask
;
248 osize
= size
= (mask
+ 1) * sizeof(*table
);
252 if (++shift
> hash
->max_shift
)
258 table
= nl_pid_hash_alloc(size
);
262 memset(table
, 0, size
);
263 otable
= hash
->table
;
267 get_random_bytes(&hash
->rnd
, sizeof(hash
->rnd
));
269 for (i
= 0; i
<= omask
; i
++) {
271 struct hlist_node
*node
, *tmp
;
273 sk_for_each_safe(sk
, node
, tmp
, &otable
[i
])
274 __sk_add_node(sk
, nl_pid_hashfn(hash
, nlk_sk(sk
)->pid
));
277 nl_pid_hash_free(otable
, osize
);
278 hash
->rehash_time
= jiffies
+ 10 * 60 * HZ
;
282 static inline int nl_pid_hash_dilute(struct nl_pid_hash
*hash
, int len
)
284 int avg
= hash
->entries
>> hash
->shift
;
286 if (unlikely(avg
> 1) && nl_pid_hash_rehash(hash
, 1))
289 if (unlikely(len
> avg
) && time_after(jiffies
, hash
->rehash_time
)) {
290 nl_pid_hash_rehash(hash
, 0);
297 static const struct proto_ops netlink_ops
;
300 netlink_update_listeners(struct sock
*sk
)
302 struct netlink_table
*tbl
= &nl_table
[sk
->sk_protocol
];
303 struct hlist_node
*node
;
307 for (i
= 0; i
< NLGRPSZ(tbl
->groups
)/sizeof(unsigned long); i
++) {
309 sk_for_each_bound(sk
, node
, &tbl
->mc_list
)
310 mask
|= nlk_sk(sk
)->groups
[i
];
311 tbl
->listeners
[i
] = mask
;
313 /* this function is only called with the netlink table "grabbed", which
314 * makes sure updates are visible before bind or setsockopt return. */
317 static int netlink_insert(struct sock
*sk
, u32 pid
)
319 struct nl_pid_hash
*hash
= &nl_table
[sk
->sk_protocol
].hash
;
320 struct hlist_head
*head
;
321 int err
= -EADDRINUSE
;
323 struct hlist_node
*node
;
326 netlink_table_grab();
327 head
= nl_pid_hashfn(hash
, pid
);
329 sk_for_each(osk
, node
, head
) {
330 if (nlk_sk(osk
)->pid
== pid
)
342 if (BITS_PER_LONG
> 32 && unlikely(hash
->entries
>= UINT_MAX
))
345 if (len
&& nl_pid_hash_dilute(hash
, len
))
346 head
= nl_pid_hashfn(hash
, pid
);
348 nlk_sk(sk
)->pid
= pid
;
349 sk_add_node(sk
, head
);
353 netlink_table_ungrab();
357 static void netlink_remove(struct sock
*sk
)
359 netlink_table_grab();
360 if (sk_del_node_init(sk
))
361 nl_table
[sk
->sk_protocol
].hash
.entries
--;
362 if (nlk_sk(sk
)->subscriptions
)
363 __sk_del_bind_node(sk
);
364 netlink_table_ungrab();
367 static struct proto netlink_proto
= {
369 .owner
= THIS_MODULE
,
370 .obj_size
= sizeof(struct netlink_sock
),
373 static int __netlink_create(struct socket
*sock
, int protocol
)
376 struct netlink_sock
*nlk
;
378 sock
->ops
= &netlink_ops
;
380 sk
= sk_alloc(PF_NETLINK
, GFP_KERNEL
, &netlink_proto
, 1);
384 sock_init_data(sock
, sk
);
387 spin_lock_init(&nlk
->cb_lock
);
388 init_waitqueue_head(&nlk
->wait
);
390 sk
->sk_destruct
= netlink_sock_destruct
;
391 sk
->sk_protocol
= protocol
;
395 static int netlink_create(struct socket
*sock
, int protocol
)
397 struct module
*module
= NULL
;
398 struct netlink_sock
*nlk
;
401 sock
->state
= SS_UNCONNECTED
;
403 if (sock
->type
!= SOCK_RAW
&& sock
->type
!= SOCK_DGRAM
)
404 return -ESOCKTNOSUPPORT
;
406 if (protocol
<0 || protocol
>= MAX_LINKS
)
407 return -EPROTONOSUPPORT
;
409 netlink_lock_table();
411 if (!nl_table
[protocol
].registered
) {
412 netlink_unlock_table();
413 request_module("net-pf-%d-proto-%d", PF_NETLINK
, protocol
);
414 netlink_lock_table();
417 if (nl_table
[protocol
].registered
&&
418 try_module_get(nl_table
[protocol
].module
))
419 module
= nl_table
[protocol
].module
;
420 netlink_unlock_table();
422 if ((err
= __netlink_create(sock
, protocol
)) < 0)
425 nlk
= nlk_sk(sock
->sk
);
426 nlk
->module
= module
;
435 static int netlink_release(struct socket
*sock
)
437 struct sock
*sk
= sock
->sk
;
438 struct netlink_sock
*nlk
;
447 spin_lock(&nlk
->cb_lock
);
450 nlk
->cb
->done(nlk
->cb
);
451 netlink_destroy_callback(nlk
->cb
);
454 spin_unlock(&nlk
->cb_lock
);
456 /* OK. Socket is unlinked, and, therefore,
457 no new packets will arrive */
460 wake_up_interruptible_all(&nlk
->wait
);
462 skb_queue_purge(&sk
->sk_write_queue
);
464 if (nlk
->pid
&& !nlk
->subscriptions
) {
465 struct netlink_notify n
= {
466 .protocol
= sk
->sk_protocol
,
469 atomic_notifier_call_chain(&netlink_chain
,
470 NETLINK_URELEASE
, &n
);
473 module_put(nlk
->module
);
475 netlink_table_grab();
476 if (nlk
->flags
& NETLINK_KERNEL_SOCKET
) {
477 kfree(nl_table
[sk
->sk_protocol
].listeners
);
478 nl_table
[sk
->sk_protocol
].module
= NULL
;
479 nl_table
[sk
->sk_protocol
].registered
= 0;
480 } else if (nlk
->subscriptions
)
481 netlink_update_listeners(sk
);
482 netlink_table_ungrab();
491 static int netlink_autobind(struct socket
*sock
)
493 struct sock
*sk
= sock
->sk
;
494 struct nl_pid_hash
*hash
= &nl_table
[sk
->sk_protocol
].hash
;
495 struct hlist_head
*head
;
497 struct hlist_node
*node
;
498 s32 pid
= current
->tgid
;
500 static s32 rover
= -4097;
504 netlink_table_grab();
505 head
= nl_pid_hashfn(hash
, pid
);
506 sk_for_each(osk
, node
, head
) {
507 if (nlk_sk(osk
)->pid
== pid
) {
508 /* Bind collision, search negative pid values. */
512 netlink_table_ungrab();
516 netlink_table_ungrab();
518 err
= netlink_insert(sk
, pid
);
519 if (err
== -EADDRINUSE
)
522 /* If 2 threads race to autobind, that is fine. */
529 static inline int netlink_capable(struct socket
*sock
, unsigned int flag
)
531 return (nl_table
[sock
->sk
->sk_protocol
].nl_nonroot
& flag
) ||
532 capable(CAP_NET_ADMIN
);
536 netlink_update_subscriptions(struct sock
*sk
, unsigned int subscriptions
)
538 struct netlink_sock
*nlk
= nlk_sk(sk
);
540 if (nlk
->subscriptions
&& !subscriptions
)
541 __sk_del_bind_node(sk
);
542 else if (!nlk
->subscriptions
&& subscriptions
)
543 sk_add_bind_node(sk
, &nl_table
[sk
->sk_protocol
].mc_list
);
544 nlk
->subscriptions
= subscriptions
;
547 static int netlink_alloc_groups(struct sock
*sk
)
549 struct netlink_sock
*nlk
= nlk_sk(sk
);
553 netlink_lock_table();
554 groups
= nl_table
[sk
->sk_protocol
].groups
;
555 if (!nl_table
[sk
->sk_protocol
].registered
)
557 netlink_unlock_table();
562 nlk
->groups
= kzalloc(NLGRPSZ(groups
), GFP_KERNEL
);
563 if (nlk
->groups
== NULL
)
565 nlk
->ngroups
= groups
;
569 static int netlink_bind(struct socket
*sock
, struct sockaddr
*addr
, int addr_len
)
571 struct sock
*sk
= sock
->sk
;
572 struct netlink_sock
*nlk
= nlk_sk(sk
);
573 struct sockaddr_nl
*nladdr
= (struct sockaddr_nl
*)addr
;
576 if (nladdr
->nl_family
!= AF_NETLINK
)
579 /* Only superuser is allowed to listen multicasts */
580 if (nladdr
->nl_groups
) {
581 if (!netlink_capable(sock
, NL_NONROOT_RECV
))
583 if (nlk
->groups
== NULL
) {
584 err
= netlink_alloc_groups(sk
);
591 if (nladdr
->nl_pid
!= nlk
->pid
)
594 err
= nladdr
->nl_pid
?
595 netlink_insert(sk
, nladdr
->nl_pid
) :
596 netlink_autobind(sock
);
601 if (!nladdr
->nl_groups
&& (nlk
->groups
== NULL
|| !(u32
)nlk
->groups
[0]))
604 netlink_table_grab();
605 netlink_update_subscriptions(sk
, nlk
->subscriptions
+
606 hweight32(nladdr
->nl_groups
) -
607 hweight32(nlk
->groups
[0]));
608 nlk
->groups
[0] = (nlk
->groups
[0] & ~0xffffffffUL
) | nladdr
->nl_groups
;
609 netlink_update_listeners(sk
);
610 netlink_table_ungrab();
615 static int netlink_connect(struct socket
*sock
, struct sockaddr
*addr
,
619 struct sock
*sk
= sock
->sk
;
620 struct netlink_sock
*nlk
= nlk_sk(sk
);
621 struct sockaddr_nl
*nladdr
=(struct sockaddr_nl
*)addr
;
623 if (addr
->sa_family
== AF_UNSPEC
) {
624 sk
->sk_state
= NETLINK_UNCONNECTED
;
629 if (addr
->sa_family
!= AF_NETLINK
)
632 /* Only superuser is allowed to send multicasts */
633 if (nladdr
->nl_groups
&& !netlink_capable(sock
, NL_NONROOT_SEND
))
637 err
= netlink_autobind(sock
);
640 sk
->sk_state
= NETLINK_CONNECTED
;
641 nlk
->dst_pid
= nladdr
->nl_pid
;
642 nlk
->dst_group
= ffs(nladdr
->nl_groups
);
648 static int netlink_getname(struct socket
*sock
, struct sockaddr
*addr
, int *addr_len
, int peer
)
650 struct sock
*sk
= sock
->sk
;
651 struct netlink_sock
*nlk
= nlk_sk(sk
);
652 struct sockaddr_nl
*nladdr
=(struct sockaddr_nl
*)addr
;
654 nladdr
->nl_family
= AF_NETLINK
;
656 *addr_len
= sizeof(*nladdr
);
659 nladdr
->nl_pid
= nlk
->dst_pid
;
660 nladdr
->nl_groups
= netlink_group_mask(nlk
->dst_group
);
662 nladdr
->nl_pid
= nlk
->pid
;
663 nladdr
->nl_groups
= nlk
->groups
? nlk
->groups
[0] : 0;
668 static void netlink_overrun(struct sock
*sk
)
670 if (!test_and_set_bit(0, &nlk_sk(sk
)->state
)) {
671 sk
->sk_err
= ENOBUFS
;
672 sk
->sk_error_report(sk
);
676 static struct sock
*netlink_getsockbypid(struct sock
*ssk
, u32 pid
)
678 int protocol
= ssk
->sk_protocol
;
680 struct netlink_sock
*nlk
;
682 sock
= netlink_lookup(protocol
, pid
);
684 return ERR_PTR(-ECONNREFUSED
);
686 /* Don't bother queuing skb if kernel socket has no input function */
688 if ((nlk
->pid
== 0 && !nlk
->data_ready
) ||
689 (sock
->sk_state
== NETLINK_CONNECTED
&&
690 nlk
->dst_pid
!= nlk_sk(ssk
)->pid
)) {
692 return ERR_PTR(-ECONNREFUSED
);
697 struct sock
*netlink_getsockbyfilp(struct file
*filp
)
699 struct inode
*inode
= filp
->f_path
.dentry
->d_inode
;
702 if (!S_ISSOCK(inode
->i_mode
))
703 return ERR_PTR(-ENOTSOCK
);
705 sock
= SOCKET_I(inode
)->sk
;
706 if (sock
->sk_family
!= AF_NETLINK
)
707 return ERR_PTR(-EINVAL
);
714 * Attach a skb to a netlink socket.
715 * The caller must hold a reference to the destination socket. On error, the
716 * reference is dropped. The skb is not send to the destination, just all
717 * all error checks are performed and memory in the queue is reserved.
719 * < 0: error. skb freed, reference to sock dropped.
721 * 1: repeat lookup - reference dropped while waiting for socket memory.
723 int netlink_attachskb(struct sock
*sk
, struct sk_buff
*skb
, int nonblock
,
724 long timeo
, struct sock
*ssk
)
726 struct netlink_sock
*nlk
;
730 if (atomic_read(&sk
->sk_rmem_alloc
) > sk
->sk_rcvbuf
||
731 test_bit(0, &nlk
->state
)) {
732 DECLARE_WAITQUEUE(wait
, current
);
734 if (!ssk
|| nlk_sk(ssk
)->pid
== 0)
741 __set_current_state(TASK_INTERRUPTIBLE
);
742 add_wait_queue(&nlk
->wait
, &wait
);
744 if ((atomic_read(&sk
->sk_rmem_alloc
) > sk
->sk_rcvbuf
||
745 test_bit(0, &nlk
->state
)) &&
746 !sock_flag(sk
, SOCK_DEAD
))
747 timeo
= schedule_timeout(timeo
);
749 __set_current_state(TASK_RUNNING
);
750 remove_wait_queue(&nlk
->wait
, &wait
);
753 if (signal_pending(current
)) {
755 return sock_intr_errno(timeo
);
759 skb_set_owner_r(skb
, sk
);
763 int netlink_sendskb(struct sock
*sk
, struct sk_buff
*skb
, int protocol
)
767 skb_queue_tail(&sk
->sk_receive_queue
, skb
);
768 sk
->sk_data_ready(sk
, len
);
773 void netlink_detachskb(struct sock
*sk
, struct sk_buff
*skb
)
779 static inline struct sk_buff
*netlink_trim(struct sk_buff
*skb
,
786 delta
= skb
->end
- skb
->tail
;
787 if (delta
* 2 < skb
->truesize
)
790 if (skb_shared(skb
)) {
791 struct sk_buff
*nskb
= skb_clone(skb
, allocation
);
798 if (!pskb_expand_head(skb
, 0, -delta
, allocation
))
799 skb
->truesize
-= delta
;
804 int netlink_unicast(struct sock
*ssk
, struct sk_buff
*skb
, u32 pid
, int nonblock
)
810 skb
= netlink_trim(skb
, gfp_any());
812 timeo
= sock_sndtimeo(ssk
, nonblock
);
814 sk
= netlink_getsockbypid(ssk
, pid
);
819 err
= netlink_attachskb(sk
, skb
, nonblock
, timeo
, ssk
);
825 return netlink_sendskb(sk
, skb
, ssk
->sk_protocol
);
828 int netlink_has_listeners(struct sock
*sk
, unsigned int group
)
832 BUG_ON(!(nlk_sk(sk
)->flags
& NETLINK_KERNEL_SOCKET
));
833 if (group
- 1 < nl_table
[sk
->sk_protocol
].groups
)
834 res
= test_bit(group
- 1, nl_table
[sk
->sk_protocol
].listeners
);
837 EXPORT_SYMBOL_GPL(netlink_has_listeners
);
839 static __inline__
int netlink_broadcast_deliver(struct sock
*sk
, struct sk_buff
*skb
)
841 struct netlink_sock
*nlk
= nlk_sk(sk
);
843 if (atomic_read(&sk
->sk_rmem_alloc
) <= sk
->sk_rcvbuf
&&
844 !test_bit(0, &nlk
->state
)) {
845 skb_set_owner_r(skb
, sk
);
846 skb_queue_tail(&sk
->sk_receive_queue
, skb
);
847 sk
->sk_data_ready(sk
, skb
->len
);
848 return atomic_read(&sk
->sk_rmem_alloc
) > sk
->sk_rcvbuf
;
853 struct netlink_broadcast_data
{
854 struct sock
*exclude_sk
;
861 struct sk_buff
*skb
, *skb2
;
864 static inline int do_one_broadcast(struct sock
*sk
,
865 struct netlink_broadcast_data
*p
)
867 struct netlink_sock
*nlk
= nlk_sk(sk
);
870 if (p
->exclude_sk
== sk
)
873 if (nlk
->pid
== p
->pid
|| p
->group
- 1 >= nlk
->ngroups
||
874 !test_bit(p
->group
- 1, nlk
->groups
))
883 if (p
->skb2
== NULL
) {
884 if (skb_shared(p
->skb
)) {
885 p
->skb2
= skb_clone(p
->skb
, p
->allocation
);
887 p
->skb2
= skb_get(p
->skb
);
889 * skb ownership may have been set when
890 * delivered to a previous socket.
895 if (p
->skb2
== NULL
) {
897 /* Clone failed. Notify ALL listeners. */
899 } else if ((val
= netlink_broadcast_deliver(sk
, p
->skb2
)) < 0) {
912 int netlink_broadcast(struct sock
*ssk
, struct sk_buff
*skb
, u32 pid
,
913 u32 group
, gfp_t allocation
)
915 struct netlink_broadcast_data info
;
916 struct hlist_node
*node
;
919 skb
= netlink_trim(skb
, allocation
);
921 info
.exclude_sk
= ssk
;
927 info
.allocation
= allocation
;
931 /* While we sleep in clone, do not allow to change socket list */
933 netlink_lock_table();
935 sk_for_each_bound(sk
, node
, &nl_table
[ssk
->sk_protocol
].mc_list
)
936 do_one_broadcast(sk
, &info
);
940 netlink_unlock_table();
943 kfree_skb(info
.skb2
);
945 if (info
.delivered
) {
946 if (info
.congested
&& (allocation
& __GFP_WAIT
))
955 struct netlink_set_err_data
{
956 struct sock
*exclude_sk
;
962 static inline int do_one_set_err(struct sock
*sk
,
963 struct netlink_set_err_data
*p
)
965 struct netlink_sock
*nlk
= nlk_sk(sk
);
967 if (sk
== p
->exclude_sk
)
970 if (nlk
->pid
== p
->pid
|| p
->group
- 1 >= nlk
->ngroups
||
971 !test_bit(p
->group
- 1, nlk
->groups
))
974 sk
->sk_err
= p
->code
;
975 sk
->sk_error_report(sk
);
980 void netlink_set_err(struct sock
*ssk
, u32 pid
, u32 group
, int code
)
982 struct netlink_set_err_data info
;
983 struct hlist_node
*node
;
986 info
.exclude_sk
= ssk
;
991 read_lock(&nl_table_lock
);
993 sk_for_each_bound(sk
, node
, &nl_table
[ssk
->sk_protocol
].mc_list
)
994 do_one_set_err(sk
, &info
);
996 read_unlock(&nl_table_lock
);
999 static int netlink_setsockopt(struct socket
*sock
, int level
, int optname
,
1000 char __user
*optval
, int optlen
)
1002 struct sock
*sk
= sock
->sk
;
1003 struct netlink_sock
*nlk
= nlk_sk(sk
);
1006 if (level
!= SOL_NETLINK
)
1007 return -ENOPROTOOPT
;
1009 if (optlen
>= sizeof(int) &&
1010 get_user(val
, (int __user
*)optval
))
1014 case NETLINK_PKTINFO
:
1016 nlk
->flags
|= NETLINK_RECV_PKTINFO
;
1018 nlk
->flags
&= ~NETLINK_RECV_PKTINFO
;
1021 case NETLINK_ADD_MEMBERSHIP
:
1022 case NETLINK_DROP_MEMBERSHIP
: {
1023 unsigned int subscriptions
;
1024 int old
, new = optname
== NETLINK_ADD_MEMBERSHIP
? 1 : 0;
1026 if (!netlink_capable(sock
, NL_NONROOT_RECV
))
1028 if (nlk
->groups
== NULL
) {
1029 err
= netlink_alloc_groups(sk
);
1033 if (!val
|| val
- 1 >= nlk
->ngroups
)
1035 netlink_table_grab();
1036 old
= test_bit(val
- 1, nlk
->groups
);
1037 subscriptions
= nlk
->subscriptions
- old
+ new;
1039 __set_bit(val
- 1, nlk
->groups
);
1041 __clear_bit(val
- 1, nlk
->groups
);
1042 netlink_update_subscriptions(sk
, subscriptions
);
1043 netlink_update_listeners(sk
);
1044 netlink_table_ungrab();
1054 static int netlink_getsockopt(struct socket
*sock
, int level
, int optname
,
1055 char __user
*optval
, int __user
*optlen
)
1057 struct sock
*sk
= sock
->sk
;
1058 struct netlink_sock
*nlk
= nlk_sk(sk
);
1061 if (level
!= SOL_NETLINK
)
1062 return -ENOPROTOOPT
;
1064 if (get_user(len
, optlen
))
1070 case NETLINK_PKTINFO
:
1071 if (len
< sizeof(int))
1074 val
= nlk
->flags
& NETLINK_RECV_PKTINFO
? 1 : 0;
1075 if (put_user(len
, optlen
) ||
1076 put_user(val
, optval
))
1086 static void netlink_cmsg_recv_pktinfo(struct msghdr
*msg
, struct sk_buff
*skb
)
1088 struct nl_pktinfo info
;
1090 info
.group
= NETLINK_CB(skb
).dst_group
;
1091 put_cmsg(msg
, SOL_NETLINK
, NETLINK_PKTINFO
, sizeof(info
), &info
);
1094 static inline void netlink_rcv_wake(struct sock
*sk
)
1096 struct netlink_sock
*nlk
= nlk_sk(sk
);
1098 if (skb_queue_empty(&sk
->sk_receive_queue
))
1099 clear_bit(0, &nlk
->state
);
1100 if (!test_bit(0, &nlk
->state
))
1101 wake_up_interruptible(&nlk
->wait
);
1104 static int netlink_sendmsg(struct kiocb
*kiocb
, struct socket
*sock
,
1105 struct msghdr
*msg
, size_t len
)
1107 struct sock_iocb
*siocb
= kiocb_to_siocb(kiocb
);
1108 struct sock
*sk
= sock
->sk
;
1109 struct netlink_sock
*nlk
= nlk_sk(sk
);
1110 struct sockaddr_nl
*addr
=msg
->msg_name
;
1113 struct sk_buff
*skb
;
1115 struct scm_cookie scm
;
1117 if (msg
->msg_flags
&MSG_OOB
)
1120 if (NULL
== siocb
->scm
)
1122 err
= scm_send(sock
, msg
, siocb
->scm
);
1126 if (msg
->msg_namelen
) {
1127 if (addr
->nl_family
!= AF_NETLINK
)
1129 dst_pid
= addr
->nl_pid
;
1130 dst_group
= ffs(addr
->nl_groups
);
1131 if (dst_group
&& !netlink_capable(sock
, NL_NONROOT_SEND
))
1134 dst_pid
= nlk
->dst_pid
;
1135 dst_group
= nlk
->dst_group
;
1139 err
= netlink_autobind(sock
);
1145 if (len
> sk
->sk_sndbuf
- 32)
1148 skb
= alloc_skb(len
, GFP_KERNEL
);
1152 NETLINK_CB(skb
).pid
= nlk
->pid
;
1153 NETLINK_CB(skb
).dst_group
= dst_group
;
1154 NETLINK_CB(skb
).loginuid
= audit_get_loginuid(current
->audit_context
);
1155 selinux_get_task_sid(current
, &(NETLINK_CB(skb
).sid
));
1156 memcpy(NETLINK_CREDS(skb
), &siocb
->scm
->creds
, sizeof(struct ucred
));
1158 /* What can I do? Netlink is asynchronous, so that
1159 we will have to save current capabilities to
1160 check them, when this message will be delivered
1161 to corresponding kernel module. --ANK (980802)
1165 if (memcpy_fromiovec(skb_put(skb
,len
), msg
->msg_iov
, len
)) {
1170 err
= security_netlink_send(sk
, skb
);
1177 atomic_inc(&skb
->users
);
1178 netlink_broadcast(sk
, skb
, dst_pid
, dst_group
, GFP_KERNEL
);
1180 err
= netlink_unicast(sk
, skb
, dst_pid
, msg
->msg_flags
&MSG_DONTWAIT
);
1186 static int netlink_recvmsg(struct kiocb
*kiocb
, struct socket
*sock
,
1187 struct msghdr
*msg
, size_t len
,
1190 struct sock_iocb
*siocb
= kiocb_to_siocb(kiocb
);
1191 struct scm_cookie scm
;
1192 struct sock
*sk
= sock
->sk
;
1193 struct netlink_sock
*nlk
= nlk_sk(sk
);
1194 int noblock
= flags
&MSG_DONTWAIT
;
1196 struct sk_buff
*skb
;
1204 skb
= skb_recv_datagram(sk
,flags
,noblock
,&err
);
1208 msg
->msg_namelen
= 0;
1212 msg
->msg_flags
|= MSG_TRUNC
;
1216 skb_reset_transport_header(skb
);
1217 err
= skb_copy_datagram_iovec(skb
, 0, msg
->msg_iov
, copied
);
1219 if (msg
->msg_name
) {
1220 struct sockaddr_nl
*addr
= (struct sockaddr_nl
*)msg
->msg_name
;
1221 addr
->nl_family
= AF_NETLINK
;
1223 addr
->nl_pid
= NETLINK_CB(skb
).pid
;
1224 addr
->nl_groups
= netlink_group_mask(NETLINK_CB(skb
).dst_group
);
1225 msg
->msg_namelen
= sizeof(*addr
);
1228 if (nlk
->flags
& NETLINK_RECV_PKTINFO
)
1229 netlink_cmsg_recv_pktinfo(msg
, skb
);
1231 if (NULL
== siocb
->scm
) {
1232 memset(&scm
, 0, sizeof(scm
));
1235 siocb
->scm
->creds
= *NETLINK_CREDS(skb
);
1236 skb_free_datagram(sk
, skb
);
1238 if (nlk
->cb
&& atomic_read(&sk
->sk_rmem_alloc
) <= sk
->sk_rcvbuf
/ 2)
1241 scm_recv(sock
, msg
, siocb
->scm
, flags
);
1243 if (flags
& MSG_TRUNC
)
1247 netlink_rcv_wake(sk
);
1248 return err
? : copied
;
1251 static void netlink_data_ready(struct sock
*sk
, int len
)
1253 struct netlink_sock
*nlk
= nlk_sk(sk
);
1255 if (nlk
->data_ready
)
1256 nlk
->data_ready(sk
, len
);
1257 netlink_rcv_wake(sk
);
1261 * We export these functions to other modules. They provide a
1262 * complete set of kernel non-blocking support for message
1267 netlink_kernel_create(int unit
, unsigned int groups
,
1268 void (*input
)(struct sock
*sk
, int len
),
1269 struct module
*module
)
1271 struct socket
*sock
;
1273 struct netlink_sock
*nlk
;
1274 unsigned long *listeners
= NULL
;
1278 if (unit
<0 || unit
>=MAX_LINKS
)
1281 if (sock_create_lite(PF_NETLINK
, SOCK_DGRAM
, unit
, &sock
))
1284 if (__netlink_create(sock
, unit
) < 0)
1285 goto out_sock_release
;
1290 listeners
= kzalloc(NLGRPSZ(groups
), GFP_KERNEL
);
1292 goto out_sock_release
;
1295 sk
->sk_data_ready
= netlink_data_ready
;
1297 nlk_sk(sk
)->data_ready
= input
;
1299 if (netlink_insert(sk
, 0))
1300 goto out_sock_release
;
1303 nlk
->flags
|= NETLINK_KERNEL_SOCKET
;
1305 netlink_table_grab();
1306 nl_table
[unit
].groups
= groups
;
1307 nl_table
[unit
].listeners
= listeners
;
1308 nl_table
[unit
].module
= module
;
1309 nl_table
[unit
].registered
= 1;
1310 netlink_table_ungrab();
1320 void netlink_set_nonroot(int protocol
, unsigned int flags
)
1322 if ((unsigned int)protocol
< MAX_LINKS
)
1323 nl_table
[protocol
].nl_nonroot
= flags
;
1326 static void netlink_destroy_callback(struct netlink_callback
*cb
)
1334 * It looks a bit ugly.
1335 * It would be better to create kernel thread.
1338 static int netlink_dump(struct sock
*sk
)
1340 struct netlink_sock
*nlk
= nlk_sk(sk
);
1341 struct netlink_callback
*cb
;
1342 struct sk_buff
*skb
;
1343 struct nlmsghdr
*nlh
;
1344 int len
, err
= -ENOBUFS
;
1346 skb
= sock_rmalloc(sk
, NLMSG_GOODSIZE
, 0, GFP_KERNEL
);
1350 spin_lock(&nlk
->cb_lock
);
1358 len
= cb
->dump(skb
, cb
);
1361 spin_unlock(&nlk
->cb_lock
);
1362 skb_queue_tail(&sk
->sk_receive_queue
, skb
);
1363 sk
->sk_data_ready(sk
, len
);
1367 nlh
= nlmsg_put_answer(skb
, cb
, NLMSG_DONE
, sizeof(len
), NLM_F_MULTI
);
1371 memcpy(nlmsg_data(nlh
), &len
, sizeof(len
));
1373 skb_queue_tail(&sk
->sk_receive_queue
, skb
);
1374 sk
->sk_data_ready(sk
, skb
->len
);
1379 spin_unlock(&nlk
->cb_lock
);
1381 netlink_destroy_callback(cb
);
1385 spin_unlock(&nlk
->cb_lock
);
1391 int netlink_dump_start(struct sock
*ssk
, struct sk_buff
*skb
,
1392 struct nlmsghdr
*nlh
,
1393 int (*dump
)(struct sk_buff
*skb
, struct netlink_callback
*),
1394 int (*done
)(struct netlink_callback
*))
1396 struct netlink_callback
*cb
;
1398 struct netlink_sock
*nlk
;
1400 cb
= kzalloc(sizeof(*cb
), GFP_KERNEL
);
1407 atomic_inc(&skb
->users
);
1410 sk
= netlink_lookup(ssk
->sk_protocol
, NETLINK_CB(skb
).pid
);
1412 netlink_destroy_callback(cb
);
1413 return -ECONNREFUSED
;
1416 /* A dump or destruction is in progress... */
1417 spin_lock(&nlk
->cb_lock
);
1418 if (nlk
->cb
|| sock_flag(sk
, SOCK_DEAD
)) {
1419 spin_unlock(&nlk
->cb_lock
);
1420 netlink_destroy_callback(cb
);
1425 spin_unlock(&nlk
->cb_lock
);
1432 void netlink_ack(struct sk_buff
*in_skb
, struct nlmsghdr
*nlh
, int err
)
1434 struct sk_buff
*skb
;
1435 struct nlmsghdr
*rep
;
1436 struct nlmsgerr
*errmsg
;
1437 size_t payload
= sizeof(*errmsg
);
1439 /* error messages get the original request appened */
1441 payload
+= nlmsg_len(nlh
);
1443 skb
= nlmsg_new(payload
, GFP_KERNEL
);
1447 sk
= netlink_lookup(in_skb
->sk
->sk_protocol
,
1448 NETLINK_CB(in_skb
).pid
);
1450 sk
->sk_err
= ENOBUFS
;
1451 sk
->sk_error_report(sk
);
1457 rep
= __nlmsg_put(skb
, NETLINK_CB(in_skb
).pid
, nlh
->nlmsg_seq
,
1458 NLMSG_ERROR
, sizeof(struct nlmsgerr
), 0);
1459 errmsg
= nlmsg_data(rep
);
1460 errmsg
->error
= err
;
1461 memcpy(&errmsg
->msg
, nlh
, err
? nlh
->nlmsg_len
: sizeof(*nlh
));
1462 netlink_unicast(in_skb
->sk
, skb
, NETLINK_CB(in_skb
).pid
, MSG_DONTWAIT
);
1465 static int netlink_rcv_skb(struct sk_buff
*skb
, int (*cb
)(struct sk_buff
*,
1466 struct nlmsghdr
*, int *))
1468 struct nlmsghdr
*nlh
;
1471 while (skb
->len
>= nlmsg_total_size(0)) {
1472 nlh
= nlmsg_hdr(skb
);
1475 if (nlh
->nlmsg_len
< NLMSG_HDRLEN
|| skb
->len
< nlh
->nlmsg_len
)
1478 /* Only requests are handled by the kernel */
1479 if (!(nlh
->nlmsg_flags
& NLM_F_REQUEST
))
1482 /* Skip control messages */
1483 if (nlh
->nlmsg_type
< NLMSG_MIN_TYPE
)
1486 if (cb(skb
, nlh
, &err
) < 0) {
1487 /* Not an error, but we have to interrupt processing
1488 * here. Note: that in this case we do not pull
1489 * message from skb, it will be processed later.
1495 if (nlh
->nlmsg_flags
& NLM_F_ACK
|| err
)
1496 netlink_ack(skb
, nlh
, err
);
1498 netlink_queue_skip(nlh
, skb
);
1505 * nelink_run_queue - Process netlink receive queue.
1506 * @sk: Netlink socket containing the queue
1507 * @qlen: Place to store queue length upon entry
1508 * @cb: Callback function invoked for each netlink message found
1510 * Processes as much as there was in the queue upon entry and invokes
1511 * a callback function for each netlink message found. The callback
1512 * function may refuse a message by returning a negative error code
1513 * but setting the error pointer to 0 in which case this function
1514 * returns with a qlen != 0.
1516 * qlen must be initialized to 0 before the initial entry, afterwards
1517 * the function may be called repeatedly until qlen reaches 0.
1519 void netlink_run_queue(struct sock
*sk
, unsigned int *qlen
,
1520 int (*cb
)(struct sk_buff
*, struct nlmsghdr
*, int *))
1522 struct sk_buff
*skb
;
1524 if (!*qlen
|| *qlen
> skb_queue_len(&sk
->sk_receive_queue
))
1525 *qlen
= skb_queue_len(&sk
->sk_receive_queue
);
1527 for (; *qlen
; (*qlen
)--) {
1528 skb
= skb_dequeue(&sk
->sk_receive_queue
);
1529 if (netlink_rcv_skb(skb
, cb
)) {
1531 skb_queue_head(&sk
->sk_receive_queue
, skb
);
1544 * netlink_queue_skip - Skip netlink message while processing queue.
1545 * @nlh: Netlink message to be skipped
1546 * @skb: Socket buffer containing the netlink messages.
1548 * Pulls the given netlink message off the socket buffer so the next
1549 * call to netlink_queue_run() will not reconsider the message.
1551 void netlink_queue_skip(struct nlmsghdr
*nlh
, struct sk_buff
*skb
)
1553 int msglen
= NLMSG_ALIGN(nlh
->nlmsg_len
);
1555 if (msglen
> skb
->len
)
1558 skb_pull(skb
, msglen
);
1562 * nlmsg_notify - send a notification netlink message
1563 * @sk: netlink socket to use
1564 * @skb: notification message
1565 * @pid: destination netlink pid for reports or 0
1566 * @group: destination multicast group or 0
1567 * @report: 1 to report back, 0 to disable
1568 * @flags: allocation flags
1570 int nlmsg_notify(struct sock
*sk
, struct sk_buff
*skb
, u32 pid
,
1571 unsigned int group
, int report
, gfp_t flags
)
1576 int exclude_pid
= 0;
1579 atomic_inc(&skb
->users
);
1583 /* errors reported via destination sk->sk_err */
1584 nlmsg_multicast(sk
, skb
, exclude_pid
, group
, flags
);
1588 err
= nlmsg_unicast(sk
, skb
, pid
);
1593 #ifdef CONFIG_PROC_FS
1594 struct nl_seq_iter
{
1599 static struct sock
*netlink_seq_socket_idx(struct seq_file
*seq
, loff_t pos
)
1601 struct nl_seq_iter
*iter
= seq
->private;
1604 struct hlist_node
*node
;
1607 for (i
=0; i
<MAX_LINKS
; i
++) {
1608 struct nl_pid_hash
*hash
= &nl_table
[i
].hash
;
1610 for (j
= 0; j
<= hash
->mask
; j
++) {
1611 sk_for_each(s
, node
, &hash
->table
[j
]) {
1624 static void *netlink_seq_start(struct seq_file
*seq
, loff_t
*pos
)
1626 read_lock(&nl_table_lock
);
1627 return *pos
? netlink_seq_socket_idx(seq
, *pos
- 1) : SEQ_START_TOKEN
;
1630 static void *netlink_seq_next(struct seq_file
*seq
, void *v
, loff_t
*pos
)
1633 struct nl_seq_iter
*iter
;
1638 if (v
== SEQ_START_TOKEN
)
1639 return netlink_seq_socket_idx(seq
, 0);
1645 iter
= seq
->private;
1647 j
= iter
->hash_idx
+ 1;
1650 struct nl_pid_hash
*hash
= &nl_table
[i
].hash
;
1652 for (; j
<= hash
->mask
; j
++) {
1653 s
= sk_head(&hash
->table
[j
]);
1662 } while (++i
< MAX_LINKS
);
1667 static void netlink_seq_stop(struct seq_file
*seq
, void *v
)
1669 read_unlock(&nl_table_lock
);
1673 static int netlink_seq_show(struct seq_file
*seq
, void *v
)
1675 if (v
== SEQ_START_TOKEN
)
1677 "sk Eth Pid Groups "
1678 "Rmem Wmem Dump Locks\n");
1681 struct netlink_sock
*nlk
= nlk_sk(s
);
1683 seq_printf(seq
, "%p %-3d %-6d %08x %-8d %-8d %p %d\n",
1687 nlk
->groups
? (u32
)nlk
->groups
[0] : 0,
1688 atomic_read(&s
->sk_rmem_alloc
),
1689 atomic_read(&s
->sk_wmem_alloc
),
1691 atomic_read(&s
->sk_refcnt
)
1698 static struct seq_operations netlink_seq_ops
= {
1699 .start
= netlink_seq_start
,
1700 .next
= netlink_seq_next
,
1701 .stop
= netlink_seq_stop
,
1702 .show
= netlink_seq_show
,
1706 static int netlink_seq_open(struct inode
*inode
, struct file
*file
)
1708 struct seq_file
*seq
;
1709 struct nl_seq_iter
*iter
;
1712 iter
= kzalloc(sizeof(*iter
), GFP_KERNEL
);
1716 err
= seq_open(file
, &netlink_seq_ops
);
1722 seq
= file
->private_data
;
1723 seq
->private = iter
;
1727 static const struct file_operations netlink_seq_fops
= {
1728 .owner
= THIS_MODULE
,
1729 .open
= netlink_seq_open
,
1731 .llseek
= seq_lseek
,
1732 .release
= seq_release_private
,
1737 int netlink_register_notifier(struct notifier_block
*nb
)
1739 return atomic_notifier_chain_register(&netlink_chain
, nb
);
1742 int netlink_unregister_notifier(struct notifier_block
*nb
)
1744 return atomic_notifier_chain_unregister(&netlink_chain
, nb
);
1747 static const struct proto_ops netlink_ops
= {
1748 .family
= PF_NETLINK
,
1749 .owner
= THIS_MODULE
,
1750 .release
= netlink_release
,
1751 .bind
= netlink_bind
,
1752 .connect
= netlink_connect
,
1753 .socketpair
= sock_no_socketpair
,
1754 .accept
= sock_no_accept
,
1755 .getname
= netlink_getname
,
1756 .poll
= datagram_poll
,
1757 .ioctl
= sock_no_ioctl
,
1758 .listen
= sock_no_listen
,
1759 .shutdown
= sock_no_shutdown
,
1760 .setsockopt
= netlink_setsockopt
,
1761 .getsockopt
= netlink_getsockopt
,
1762 .sendmsg
= netlink_sendmsg
,
1763 .recvmsg
= netlink_recvmsg
,
1764 .mmap
= sock_no_mmap
,
1765 .sendpage
= sock_no_sendpage
,
1768 static struct net_proto_family netlink_family_ops
= {
1769 .family
= PF_NETLINK
,
1770 .create
= netlink_create
,
1771 .owner
= THIS_MODULE
, /* for consistency 8) */
1774 static int __init
netlink_proto_init(void)
1776 struct sk_buff
*dummy_skb
;
1780 int err
= proto_register(&netlink_proto
, 0);
1785 BUILD_BUG_ON(sizeof(struct netlink_skb_parms
) > sizeof(dummy_skb
->cb
));
1787 nl_table
= kcalloc(MAX_LINKS
, sizeof(*nl_table
), GFP_KERNEL
);
1791 if (num_physpages
>= (128 * 1024))
1792 max
= num_physpages
>> (21 - PAGE_SHIFT
);
1794 max
= num_physpages
>> (23 - PAGE_SHIFT
);
1796 order
= get_bitmask_order(max
) - 1 + PAGE_SHIFT
;
1797 max
= (1UL << order
) / sizeof(struct hlist_head
);
1798 order
= get_bitmask_order(max
> UINT_MAX
? UINT_MAX
: max
) - 1;
1800 for (i
= 0; i
< MAX_LINKS
; i
++) {
1801 struct nl_pid_hash
*hash
= &nl_table
[i
].hash
;
1803 hash
->table
= nl_pid_hash_alloc(1 * sizeof(*hash
->table
));
1806 nl_pid_hash_free(nl_table
[i
].hash
.table
,
1807 1 * sizeof(*hash
->table
));
1811 memset(hash
->table
, 0, 1 * sizeof(*hash
->table
));
1812 hash
->max_shift
= order
;
1815 hash
->rehash_time
= jiffies
;
1818 sock_register(&netlink_family_ops
);
1819 #ifdef CONFIG_PROC_FS
1820 proc_net_fops_create("netlink", 0, &netlink_seq_fops
);
1822 /* The netlink device handler may be needed early. */
1827 panic("netlink_init: Cannot allocate nl_table\n");
1830 core_initcall(netlink_proto_init
);
1832 EXPORT_SYMBOL(netlink_ack
);
1833 EXPORT_SYMBOL(netlink_run_queue
);
1834 EXPORT_SYMBOL(netlink_queue_skip
);
1835 EXPORT_SYMBOL(netlink_broadcast
);
1836 EXPORT_SYMBOL(netlink_dump_start
);
1837 EXPORT_SYMBOL(netlink_kernel_create
);
1838 EXPORT_SYMBOL(netlink_register_notifier
);
1839 EXPORT_SYMBOL(netlink_set_nonroot
);
1840 EXPORT_SYMBOL(netlink_unicast
);
1841 EXPORT_SYMBOL(netlink_unregister_notifier
);
1842 EXPORT_SYMBOL(nlmsg_notify
);