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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * NETLINK Kernel-user communication protocol. | |
3 | * | |
4 | * Authors: Alan Cox <alan@redhat.com> | |
5 | * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or | |
8 | * modify it under the terms of the GNU General Public License | |
9 | * as published by the Free Software Foundation; either version | |
10 | * 2 of the License, or (at your option) any later version. | |
746fac4d | 11 | * |
1da177e4 LT |
12 | * Tue Jun 26 14:36:48 MEST 2001 Herbert "herp" Rosmanith |
13 | * added netlink_proto_exit | |
14 | * Tue Jan 22 18:32:44 BRST 2002 Arnaldo C. de Melo <acme@conectiva.com.br> | |
15 | * use nlk_sk, as sk->protinfo is on a diet 8) | |
4fdb3bb7 HW |
16 | * Fri Jul 22 19:51:12 MEST 2005 Harald Welte <laforge@gnumonks.org> |
17 | * - inc module use count of module that owns | |
18 | * the kernel socket in case userspace opens | |
19 | * socket of same protocol | |
20 | * - remove all module support, since netlink is | |
21 | * mandatory if CONFIG_NET=y these days | |
1da177e4 LT |
22 | */ |
23 | ||
1da177e4 LT |
24 | #include <linux/module.h> |
25 | ||
4fc268d2 | 26 | #include <linux/capability.h> |
1da177e4 LT |
27 | #include <linux/kernel.h> |
28 | #include <linux/init.h> | |
1da177e4 LT |
29 | #include <linux/signal.h> |
30 | #include <linux/sched.h> | |
31 | #include <linux/errno.h> | |
32 | #include <linux/string.h> | |
33 | #include <linux/stat.h> | |
34 | #include <linux/socket.h> | |
35 | #include <linux/un.h> | |
36 | #include <linux/fcntl.h> | |
37 | #include <linux/termios.h> | |
38 | #include <linux/sockios.h> | |
39 | #include <linux/net.h> | |
40 | #include <linux/fs.h> | |
41 | #include <linux/slab.h> | |
42 | #include <asm/uaccess.h> | |
43 | #include <linux/skbuff.h> | |
44 | #include <linux/netdevice.h> | |
45 | #include <linux/rtnetlink.h> | |
46 | #include <linux/proc_fs.h> | |
47 | #include <linux/seq_file.h> | |
1da177e4 LT |
48 | #include <linux/notifier.h> |
49 | #include <linux/security.h> | |
50 | #include <linux/jhash.h> | |
51 | #include <linux/jiffies.h> | |
52 | #include <linux/random.h> | |
53 | #include <linux/bitops.h> | |
54 | #include <linux/mm.h> | |
55 | #include <linux/types.h> | |
54e0f520 | 56 | #include <linux/audit.h> |
e7c34970 | 57 | #include <linux/selinux.h> |
af65bdfc | 58 | #include <linux/mutex.h> |
54e0f520 | 59 | |
1da177e4 LT |
60 | #include <net/sock.h> |
61 | #include <net/scm.h> | |
82ace47a | 62 | #include <net/netlink.h> |
1da177e4 | 63 | |
f7fa9b10 | 64 | #define NLGRPSZ(x) (ALIGN(x, sizeof(unsigned long) * 8) / 8) |
1da177e4 LT |
65 | |
66 | struct netlink_sock { | |
67 | /* struct sock has to be the first member of netlink_sock */ | |
68 | struct sock sk; | |
69 | u32 pid; | |
1da177e4 | 70 | u32 dst_pid; |
d629b836 | 71 | u32 dst_group; |
f7fa9b10 PM |
72 | u32 flags; |
73 | u32 subscriptions; | |
74 | u32 ngroups; | |
75 | unsigned long *groups; | |
1da177e4 LT |
76 | unsigned long state; |
77 | wait_queue_head_t wait; | |
78 | struct netlink_callback *cb; | |
af65bdfc PM |
79 | struct mutex *cb_mutex; |
80 | struct mutex cb_def_mutex; | |
1da177e4 | 81 | void (*data_ready)(struct sock *sk, int bytes); |
77247bbb | 82 | struct module *module; |
1da177e4 LT |
83 | }; |
84 | ||
77247bbb | 85 | #define NETLINK_KERNEL_SOCKET 0x1 |
9a4595bc | 86 | #define NETLINK_RECV_PKTINFO 0x2 |
77247bbb | 87 | |
1da177e4 LT |
88 | static inline struct netlink_sock *nlk_sk(struct sock *sk) |
89 | { | |
90 | return (struct netlink_sock *)sk; | |
91 | } | |
92 | ||
93 | struct nl_pid_hash { | |
94 | struct hlist_head *table; | |
95 | unsigned long rehash_time; | |
96 | ||
97 | unsigned int mask; | |
98 | unsigned int shift; | |
99 | ||
100 | unsigned int entries; | |
101 | unsigned int max_shift; | |
102 | ||
103 | u32 rnd; | |
104 | }; | |
105 | ||
106 | struct netlink_table { | |
107 | struct nl_pid_hash hash; | |
108 | struct hlist_head mc_list; | |
4277a083 | 109 | unsigned long *listeners; |
1da177e4 | 110 | unsigned int nl_nonroot; |
f7fa9b10 | 111 | unsigned int groups; |
af65bdfc | 112 | struct mutex *cb_mutex; |
77247bbb | 113 | struct module *module; |
ab33a171 | 114 | int registered; |
1da177e4 LT |
115 | }; |
116 | ||
117 | static struct netlink_table *nl_table; | |
118 | ||
119 | static DECLARE_WAIT_QUEUE_HEAD(nl_table_wait); | |
120 | ||
121 | static int netlink_dump(struct sock *sk); | |
122 | static void netlink_destroy_callback(struct netlink_callback *cb); | |
42bad1da | 123 | static void netlink_queue_skip(struct nlmsghdr *nlh, struct sk_buff *skb); |
1da177e4 LT |
124 | |
125 | static DEFINE_RWLOCK(nl_table_lock); | |
126 | static atomic_t nl_table_users = ATOMIC_INIT(0); | |
127 | ||
e041c683 | 128 | static ATOMIC_NOTIFIER_HEAD(netlink_chain); |
1da177e4 | 129 | |
d629b836 PM |
130 | static u32 netlink_group_mask(u32 group) |
131 | { | |
132 | return group ? 1 << (group - 1) : 0; | |
133 | } | |
134 | ||
1da177e4 LT |
135 | static struct hlist_head *nl_pid_hashfn(struct nl_pid_hash *hash, u32 pid) |
136 | { | |
137 | return &hash->table[jhash_1word(pid, hash->rnd) & hash->mask]; | |
138 | } | |
139 | ||
140 | static void netlink_sock_destruct(struct sock *sk) | |
141 | { | |
3f660d66 HX |
142 | struct netlink_sock *nlk = nlk_sk(sk); |
143 | ||
3f660d66 HX |
144 | if (nlk->cb) { |
145 | if (nlk->cb->done) | |
146 | nlk->cb->done(nlk->cb); | |
147 | netlink_destroy_callback(nlk->cb); | |
148 | } | |
149 | ||
1da177e4 LT |
150 | skb_queue_purge(&sk->sk_receive_queue); |
151 | ||
152 | if (!sock_flag(sk, SOCK_DEAD)) { | |
153 | printk("Freeing alive netlink socket %p\n", sk); | |
154 | return; | |
155 | } | |
156 | BUG_TRAP(!atomic_read(&sk->sk_rmem_alloc)); | |
157 | BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc)); | |
f7fa9b10 | 158 | BUG_TRAP(!nlk_sk(sk)->groups); |
1da177e4 LT |
159 | } |
160 | ||
161 | /* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on SMP. | |
162 | * Look, when several writers sleep and reader wakes them up, all but one | |
163 | * immediately hit write lock and grab all the cpus. Exclusive sleep solves | |
164 | * this, _but_ remember, it adds useless work on UP machines. | |
165 | */ | |
166 | ||
167 | static void netlink_table_grab(void) | |
168 | { | |
6abd219c | 169 | write_lock_irq(&nl_table_lock); |
1da177e4 LT |
170 | |
171 | if (atomic_read(&nl_table_users)) { | |
172 | DECLARE_WAITQUEUE(wait, current); | |
173 | ||
174 | add_wait_queue_exclusive(&nl_table_wait, &wait); | |
175 | for(;;) { | |
176 | set_current_state(TASK_UNINTERRUPTIBLE); | |
177 | if (atomic_read(&nl_table_users) == 0) | |
178 | break; | |
6abd219c | 179 | write_unlock_irq(&nl_table_lock); |
1da177e4 | 180 | schedule(); |
6abd219c | 181 | write_lock_irq(&nl_table_lock); |
1da177e4 LT |
182 | } |
183 | ||
184 | __set_current_state(TASK_RUNNING); | |
185 | remove_wait_queue(&nl_table_wait, &wait); | |
186 | } | |
187 | } | |
188 | ||
189 | static __inline__ void netlink_table_ungrab(void) | |
190 | { | |
6abd219c | 191 | write_unlock_irq(&nl_table_lock); |
1da177e4 LT |
192 | wake_up(&nl_table_wait); |
193 | } | |
194 | ||
195 | static __inline__ void | |
196 | netlink_lock_table(void) | |
197 | { | |
198 | /* read_lock() synchronizes us to netlink_table_grab */ | |
199 | ||
200 | read_lock(&nl_table_lock); | |
201 | atomic_inc(&nl_table_users); | |
202 | read_unlock(&nl_table_lock); | |
203 | } | |
204 | ||
205 | static __inline__ void | |
206 | netlink_unlock_table(void) | |
207 | { | |
208 | if (atomic_dec_and_test(&nl_table_users)) | |
209 | wake_up(&nl_table_wait); | |
210 | } | |
211 | ||
212 | static __inline__ struct sock *netlink_lookup(int protocol, u32 pid) | |
213 | { | |
214 | struct nl_pid_hash *hash = &nl_table[protocol].hash; | |
215 | struct hlist_head *head; | |
216 | struct sock *sk; | |
217 | struct hlist_node *node; | |
218 | ||
219 | read_lock(&nl_table_lock); | |
220 | head = nl_pid_hashfn(hash, pid); | |
221 | sk_for_each(sk, node, head) { | |
222 | if (nlk_sk(sk)->pid == pid) { | |
223 | sock_hold(sk); | |
224 | goto found; | |
225 | } | |
226 | } | |
227 | sk = NULL; | |
228 | found: | |
229 | read_unlock(&nl_table_lock); | |
230 | return sk; | |
231 | } | |
232 | ||
233 | static inline struct hlist_head *nl_pid_hash_alloc(size_t size) | |
234 | { | |
235 | if (size <= PAGE_SIZE) | |
236 | return kmalloc(size, GFP_ATOMIC); | |
237 | else | |
238 | return (struct hlist_head *) | |
239 | __get_free_pages(GFP_ATOMIC, get_order(size)); | |
240 | } | |
241 | ||
242 | static inline void nl_pid_hash_free(struct hlist_head *table, size_t size) | |
243 | { | |
244 | if (size <= PAGE_SIZE) | |
245 | kfree(table); | |
246 | else | |
247 | free_pages((unsigned long)table, get_order(size)); | |
248 | } | |
249 | ||
250 | static int nl_pid_hash_rehash(struct nl_pid_hash *hash, int grow) | |
251 | { | |
252 | unsigned int omask, mask, shift; | |
253 | size_t osize, size; | |
254 | struct hlist_head *otable, *table; | |
255 | int i; | |
256 | ||
257 | omask = mask = hash->mask; | |
258 | osize = size = (mask + 1) * sizeof(*table); | |
259 | shift = hash->shift; | |
260 | ||
261 | if (grow) { | |
262 | if (++shift > hash->max_shift) | |
263 | return 0; | |
264 | mask = mask * 2 + 1; | |
265 | size *= 2; | |
266 | } | |
267 | ||
268 | table = nl_pid_hash_alloc(size); | |
269 | if (!table) | |
270 | return 0; | |
271 | ||
272 | memset(table, 0, size); | |
273 | otable = hash->table; | |
274 | hash->table = table; | |
275 | hash->mask = mask; | |
276 | hash->shift = shift; | |
277 | get_random_bytes(&hash->rnd, sizeof(hash->rnd)); | |
278 | ||
279 | for (i = 0; i <= omask; i++) { | |
280 | struct sock *sk; | |
281 | struct hlist_node *node, *tmp; | |
282 | ||
283 | sk_for_each_safe(sk, node, tmp, &otable[i]) | |
284 | __sk_add_node(sk, nl_pid_hashfn(hash, nlk_sk(sk)->pid)); | |
285 | } | |
286 | ||
287 | nl_pid_hash_free(otable, osize); | |
288 | hash->rehash_time = jiffies + 10 * 60 * HZ; | |
289 | return 1; | |
290 | } | |
291 | ||
292 | static inline int nl_pid_hash_dilute(struct nl_pid_hash *hash, int len) | |
293 | { | |
294 | int avg = hash->entries >> hash->shift; | |
295 | ||
296 | if (unlikely(avg > 1) && nl_pid_hash_rehash(hash, 1)) | |
297 | return 1; | |
298 | ||
299 | if (unlikely(len > avg) && time_after(jiffies, hash->rehash_time)) { | |
300 | nl_pid_hash_rehash(hash, 0); | |
301 | return 1; | |
302 | } | |
303 | ||
304 | return 0; | |
305 | } | |
306 | ||
90ddc4f0 | 307 | static const struct proto_ops netlink_ops; |
1da177e4 | 308 | |
4277a083 PM |
309 | static void |
310 | netlink_update_listeners(struct sock *sk) | |
311 | { | |
312 | struct netlink_table *tbl = &nl_table[sk->sk_protocol]; | |
313 | struct hlist_node *node; | |
314 | unsigned long mask; | |
315 | unsigned int i; | |
316 | ||
317 | for (i = 0; i < NLGRPSZ(tbl->groups)/sizeof(unsigned long); i++) { | |
318 | mask = 0; | |
319 | sk_for_each_bound(sk, node, &tbl->mc_list) | |
320 | mask |= nlk_sk(sk)->groups[i]; | |
321 | tbl->listeners[i] = mask; | |
322 | } | |
323 | /* this function is only called with the netlink table "grabbed", which | |
324 | * makes sure updates are visible before bind or setsockopt return. */ | |
325 | } | |
326 | ||
1da177e4 LT |
327 | static int netlink_insert(struct sock *sk, u32 pid) |
328 | { | |
329 | struct nl_pid_hash *hash = &nl_table[sk->sk_protocol].hash; | |
330 | struct hlist_head *head; | |
331 | int err = -EADDRINUSE; | |
332 | struct sock *osk; | |
333 | struct hlist_node *node; | |
334 | int len; | |
335 | ||
336 | netlink_table_grab(); | |
337 | head = nl_pid_hashfn(hash, pid); | |
338 | len = 0; | |
339 | sk_for_each(osk, node, head) { | |
340 | if (nlk_sk(osk)->pid == pid) | |
341 | break; | |
342 | len++; | |
343 | } | |
344 | if (node) | |
345 | goto err; | |
346 | ||
347 | err = -EBUSY; | |
348 | if (nlk_sk(sk)->pid) | |
349 | goto err; | |
350 | ||
351 | err = -ENOMEM; | |
352 | if (BITS_PER_LONG > 32 && unlikely(hash->entries >= UINT_MAX)) | |
353 | goto err; | |
354 | ||
355 | if (len && nl_pid_hash_dilute(hash, len)) | |
356 | head = nl_pid_hashfn(hash, pid); | |
357 | hash->entries++; | |
358 | nlk_sk(sk)->pid = pid; | |
359 | sk_add_node(sk, head); | |
360 | err = 0; | |
361 | ||
362 | err: | |
363 | netlink_table_ungrab(); | |
364 | return err; | |
365 | } | |
366 | ||
367 | static void netlink_remove(struct sock *sk) | |
368 | { | |
369 | netlink_table_grab(); | |
d470e3b4 DM |
370 | if (sk_del_node_init(sk)) |
371 | nl_table[sk->sk_protocol].hash.entries--; | |
f7fa9b10 | 372 | if (nlk_sk(sk)->subscriptions) |
1da177e4 LT |
373 | __sk_del_bind_node(sk); |
374 | netlink_table_ungrab(); | |
375 | } | |
376 | ||
377 | static struct proto netlink_proto = { | |
378 | .name = "NETLINK", | |
379 | .owner = THIS_MODULE, | |
380 | .obj_size = sizeof(struct netlink_sock), | |
381 | }; | |
382 | ||
af65bdfc PM |
383 | static int __netlink_create(struct socket *sock, struct mutex *cb_mutex, |
384 | int protocol) | |
1da177e4 LT |
385 | { |
386 | struct sock *sk; | |
387 | struct netlink_sock *nlk; | |
ab33a171 PM |
388 | |
389 | sock->ops = &netlink_ops; | |
390 | ||
391 | sk = sk_alloc(PF_NETLINK, GFP_KERNEL, &netlink_proto, 1); | |
392 | if (!sk) | |
393 | return -ENOMEM; | |
394 | ||
395 | sock_init_data(sock, sk); | |
396 | ||
397 | nlk = nlk_sk(sk); | |
ffa4d721 PM |
398 | if (cb_mutex) |
399 | nlk->cb_mutex = cb_mutex; | |
400 | else { | |
401 | nlk->cb_mutex = &nlk->cb_def_mutex; | |
402 | mutex_init(nlk->cb_mutex); | |
403 | } | |
ab33a171 PM |
404 | init_waitqueue_head(&nlk->wait); |
405 | ||
406 | sk->sk_destruct = netlink_sock_destruct; | |
407 | sk->sk_protocol = protocol; | |
408 | return 0; | |
409 | } | |
410 | ||
411 | static int netlink_create(struct socket *sock, int protocol) | |
412 | { | |
413 | struct module *module = NULL; | |
af65bdfc | 414 | struct mutex *cb_mutex; |
f7fa9b10 | 415 | struct netlink_sock *nlk; |
ab33a171 | 416 | int err = 0; |
1da177e4 LT |
417 | |
418 | sock->state = SS_UNCONNECTED; | |
419 | ||
420 | if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM) | |
421 | return -ESOCKTNOSUPPORT; | |
422 | ||
423 | if (protocol<0 || protocol >= MAX_LINKS) | |
424 | return -EPROTONOSUPPORT; | |
425 | ||
77247bbb | 426 | netlink_lock_table(); |
4fdb3bb7 | 427 | #ifdef CONFIG_KMOD |
ab33a171 | 428 | if (!nl_table[protocol].registered) { |
77247bbb | 429 | netlink_unlock_table(); |
4fdb3bb7 | 430 | request_module("net-pf-%d-proto-%d", PF_NETLINK, protocol); |
77247bbb | 431 | netlink_lock_table(); |
4fdb3bb7 | 432 | } |
ab33a171 PM |
433 | #endif |
434 | if (nl_table[protocol].registered && | |
435 | try_module_get(nl_table[protocol].module)) | |
436 | module = nl_table[protocol].module; | |
af65bdfc | 437 | cb_mutex = nl_table[protocol].cb_mutex; |
77247bbb | 438 | netlink_unlock_table(); |
4fdb3bb7 | 439 | |
af65bdfc | 440 | if ((err = __netlink_create(sock, cb_mutex, protocol)) < 0) |
f7fa9b10 PM |
441 | goto out_module; |
442 | ||
443 | nlk = nlk_sk(sock->sk); | |
f7fa9b10 | 444 | nlk->module = module; |
ab33a171 PM |
445 | out: |
446 | return err; | |
1da177e4 | 447 | |
ab33a171 PM |
448 | out_module: |
449 | module_put(module); | |
450 | goto out; | |
1da177e4 LT |
451 | } |
452 | ||
453 | static int netlink_release(struct socket *sock) | |
454 | { | |
455 | struct sock *sk = sock->sk; | |
456 | struct netlink_sock *nlk; | |
457 | ||
458 | if (!sk) | |
459 | return 0; | |
460 | ||
461 | netlink_remove(sk); | |
ac57b3a9 | 462 | sock_orphan(sk); |
1da177e4 LT |
463 | nlk = nlk_sk(sk); |
464 | ||
3f660d66 HX |
465 | /* |
466 | * OK. Socket is unlinked, any packets that arrive now | |
467 | * will be purged. | |
468 | */ | |
1da177e4 | 469 | |
1da177e4 LT |
470 | sock->sk = NULL; |
471 | wake_up_interruptible_all(&nlk->wait); | |
472 | ||
473 | skb_queue_purge(&sk->sk_write_queue); | |
474 | ||
f7fa9b10 | 475 | if (nlk->pid && !nlk->subscriptions) { |
1da177e4 LT |
476 | struct netlink_notify n = { |
477 | .protocol = sk->sk_protocol, | |
478 | .pid = nlk->pid, | |
479 | }; | |
e041c683 AS |
480 | atomic_notifier_call_chain(&netlink_chain, |
481 | NETLINK_URELEASE, &n); | |
746fac4d | 482 | } |
4fdb3bb7 | 483 | |
5e7c001c | 484 | module_put(nlk->module); |
4fdb3bb7 | 485 | |
4277a083 | 486 | netlink_table_grab(); |
77247bbb | 487 | if (nlk->flags & NETLINK_KERNEL_SOCKET) { |
4277a083 | 488 | kfree(nl_table[sk->sk_protocol].listeners); |
77247bbb | 489 | nl_table[sk->sk_protocol].module = NULL; |
ab33a171 | 490 | nl_table[sk->sk_protocol].registered = 0; |
4277a083 PM |
491 | } else if (nlk->subscriptions) |
492 | netlink_update_listeners(sk); | |
493 | netlink_table_ungrab(); | |
77247bbb | 494 | |
f7fa9b10 PM |
495 | kfree(nlk->groups); |
496 | nlk->groups = NULL; | |
497 | ||
1da177e4 LT |
498 | sock_put(sk); |
499 | return 0; | |
500 | } | |
501 | ||
502 | static int netlink_autobind(struct socket *sock) | |
503 | { | |
504 | struct sock *sk = sock->sk; | |
505 | struct nl_pid_hash *hash = &nl_table[sk->sk_protocol].hash; | |
506 | struct hlist_head *head; | |
507 | struct sock *osk; | |
508 | struct hlist_node *node; | |
c27bd492 | 509 | s32 pid = current->tgid; |
1da177e4 LT |
510 | int err; |
511 | static s32 rover = -4097; | |
512 | ||
513 | retry: | |
514 | cond_resched(); | |
515 | netlink_table_grab(); | |
516 | head = nl_pid_hashfn(hash, pid); | |
517 | sk_for_each(osk, node, head) { | |
518 | if (nlk_sk(osk)->pid == pid) { | |
519 | /* Bind collision, search negative pid values. */ | |
520 | pid = rover--; | |
521 | if (rover > -4097) | |
522 | rover = -4097; | |
523 | netlink_table_ungrab(); | |
524 | goto retry; | |
525 | } | |
526 | } | |
527 | netlink_table_ungrab(); | |
528 | ||
529 | err = netlink_insert(sk, pid); | |
530 | if (err == -EADDRINUSE) | |
531 | goto retry; | |
d470e3b4 DM |
532 | |
533 | /* If 2 threads race to autobind, that is fine. */ | |
534 | if (err == -EBUSY) | |
535 | err = 0; | |
536 | ||
537 | return err; | |
1da177e4 LT |
538 | } |
539 | ||
746fac4d YH |
540 | static inline int netlink_capable(struct socket *sock, unsigned int flag) |
541 | { | |
1da177e4 LT |
542 | return (nl_table[sock->sk->sk_protocol].nl_nonroot & flag) || |
543 | capable(CAP_NET_ADMIN); | |
746fac4d | 544 | } |
1da177e4 | 545 | |
f7fa9b10 PM |
546 | static void |
547 | netlink_update_subscriptions(struct sock *sk, unsigned int subscriptions) | |
548 | { | |
549 | struct netlink_sock *nlk = nlk_sk(sk); | |
550 | ||
551 | if (nlk->subscriptions && !subscriptions) | |
552 | __sk_del_bind_node(sk); | |
553 | else if (!nlk->subscriptions && subscriptions) | |
554 | sk_add_bind_node(sk, &nl_table[sk->sk_protocol].mc_list); | |
555 | nlk->subscriptions = subscriptions; | |
556 | } | |
557 | ||
513c2500 PM |
558 | static int netlink_alloc_groups(struct sock *sk) |
559 | { | |
560 | struct netlink_sock *nlk = nlk_sk(sk); | |
561 | unsigned int groups; | |
562 | int err = 0; | |
563 | ||
564 | netlink_lock_table(); | |
565 | groups = nl_table[sk->sk_protocol].groups; | |
566 | if (!nl_table[sk->sk_protocol].registered) | |
567 | err = -ENOENT; | |
568 | netlink_unlock_table(); | |
569 | ||
570 | if (err) | |
571 | return err; | |
572 | ||
0da974f4 | 573 | nlk->groups = kzalloc(NLGRPSZ(groups), GFP_KERNEL); |
513c2500 PM |
574 | if (nlk->groups == NULL) |
575 | return -ENOMEM; | |
513c2500 PM |
576 | nlk->ngroups = groups; |
577 | return 0; | |
578 | } | |
579 | ||
1da177e4 LT |
580 | static int netlink_bind(struct socket *sock, struct sockaddr *addr, int addr_len) |
581 | { | |
582 | struct sock *sk = sock->sk; | |
583 | struct netlink_sock *nlk = nlk_sk(sk); | |
584 | struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr; | |
585 | int err; | |
746fac4d | 586 | |
1da177e4 LT |
587 | if (nladdr->nl_family != AF_NETLINK) |
588 | return -EINVAL; | |
589 | ||
590 | /* Only superuser is allowed to listen multicasts */ | |
513c2500 PM |
591 | if (nladdr->nl_groups) { |
592 | if (!netlink_capable(sock, NL_NONROOT_RECV)) | |
593 | return -EPERM; | |
594 | if (nlk->groups == NULL) { | |
595 | err = netlink_alloc_groups(sk); | |
596 | if (err) | |
597 | return err; | |
598 | } | |
599 | } | |
1da177e4 LT |
600 | |
601 | if (nlk->pid) { | |
602 | if (nladdr->nl_pid != nlk->pid) | |
603 | return -EINVAL; | |
604 | } else { | |
605 | err = nladdr->nl_pid ? | |
606 | netlink_insert(sk, nladdr->nl_pid) : | |
607 | netlink_autobind(sock); | |
608 | if (err) | |
609 | return err; | |
610 | } | |
611 | ||
513c2500 | 612 | if (!nladdr->nl_groups && (nlk->groups == NULL || !(u32)nlk->groups[0])) |
1da177e4 LT |
613 | return 0; |
614 | ||
615 | netlink_table_grab(); | |
f7fa9b10 | 616 | netlink_update_subscriptions(sk, nlk->subscriptions + |
746fac4d YH |
617 | hweight32(nladdr->nl_groups) - |
618 | hweight32(nlk->groups[0])); | |
619 | nlk->groups[0] = (nlk->groups[0] & ~0xffffffffUL) | nladdr->nl_groups; | |
4277a083 | 620 | netlink_update_listeners(sk); |
1da177e4 LT |
621 | netlink_table_ungrab(); |
622 | ||
623 | return 0; | |
624 | } | |
625 | ||
626 | static int netlink_connect(struct socket *sock, struct sockaddr *addr, | |
627 | int alen, int flags) | |
628 | { | |
629 | int err = 0; | |
630 | struct sock *sk = sock->sk; | |
631 | struct netlink_sock *nlk = nlk_sk(sk); | |
632 | struct sockaddr_nl *nladdr=(struct sockaddr_nl*)addr; | |
633 | ||
634 | if (addr->sa_family == AF_UNSPEC) { | |
635 | sk->sk_state = NETLINK_UNCONNECTED; | |
636 | nlk->dst_pid = 0; | |
d629b836 | 637 | nlk->dst_group = 0; |
1da177e4 LT |
638 | return 0; |
639 | } | |
640 | if (addr->sa_family != AF_NETLINK) | |
641 | return -EINVAL; | |
642 | ||
643 | /* Only superuser is allowed to send multicasts */ | |
644 | if (nladdr->nl_groups && !netlink_capable(sock, NL_NONROOT_SEND)) | |
645 | return -EPERM; | |
646 | ||
647 | if (!nlk->pid) | |
648 | err = netlink_autobind(sock); | |
649 | ||
650 | if (err == 0) { | |
651 | sk->sk_state = NETLINK_CONNECTED; | |
652 | nlk->dst_pid = nladdr->nl_pid; | |
d629b836 | 653 | nlk->dst_group = ffs(nladdr->nl_groups); |
1da177e4 LT |
654 | } |
655 | ||
656 | return err; | |
657 | } | |
658 | ||
659 | static int netlink_getname(struct socket *sock, struct sockaddr *addr, int *addr_len, int peer) | |
660 | { | |
661 | struct sock *sk = sock->sk; | |
662 | struct netlink_sock *nlk = nlk_sk(sk); | |
663 | struct sockaddr_nl *nladdr=(struct sockaddr_nl *)addr; | |
746fac4d | 664 | |
1da177e4 LT |
665 | nladdr->nl_family = AF_NETLINK; |
666 | nladdr->nl_pad = 0; | |
667 | *addr_len = sizeof(*nladdr); | |
668 | ||
669 | if (peer) { | |
670 | nladdr->nl_pid = nlk->dst_pid; | |
d629b836 | 671 | nladdr->nl_groups = netlink_group_mask(nlk->dst_group); |
1da177e4 LT |
672 | } else { |
673 | nladdr->nl_pid = nlk->pid; | |
513c2500 | 674 | nladdr->nl_groups = nlk->groups ? nlk->groups[0] : 0; |
1da177e4 LT |
675 | } |
676 | return 0; | |
677 | } | |
678 | ||
679 | static void netlink_overrun(struct sock *sk) | |
680 | { | |
681 | if (!test_and_set_bit(0, &nlk_sk(sk)->state)) { | |
682 | sk->sk_err = ENOBUFS; | |
683 | sk->sk_error_report(sk); | |
684 | } | |
685 | } | |
686 | ||
687 | static struct sock *netlink_getsockbypid(struct sock *ssk, u32 pid) | |
688 | { | |
689 | int protocol = ssk->sk_protocol; | |
690 | struct sock *sock; | |
691 | struct netlink_sock *nlk; | |
692 | ||
693 | sock = netlink_lookup(protocol, pid); | |
694 | if (!sock) | |
695 | return ERR_PTR(-ECONNREFUSED); | |
696 | ||
697 | /* Don't bother queuing skb if kernel socket has no input function */ | |
698 | nlk = nlk_sk(sock); | |
699 | if ((nlk->pid == 0 && !nlk->data_ready) || | |
700 | (sock->sk_state == NETLINK_CONNECTED && | |
701 | nlk->dst_pid != nlk_sk(ssk)->pid)) { | |
702 | sock_put(sock); | |
703 | return ERR_PTR(-ECONNREFUSED); | |
704 | } | |
705 | return sock; | |
706 | } | |
707 | ||
708 | struct sock *netlink_getsockbyfilp(struct file *filp) | |
709 | { | |
6db5fc5d | 710 | struct inode *inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
711 | struct sock *sock; |
712 | ||
713 | if (!S_ISSOCK(inode->i_mode)) | |
714 | return ERR_PTR(-ENOTSOCK); | |
715 | ||
716 | sock = SOCKET_I(inode)->sk; | |
717 | if (sock->sk_family != AF_NETLINK) | |
718 | return ERR_PTR(-EINVAL); | |
719 | ||
720 | sock_hold(sock); | |
721 | return sock; | |
722 | } | |
723 | ||
724 | /* | |
725 | * Attach a skb to a netlink socket. | |
726 | * The caller must hold a reference to the destination socket. On error, the | |
727 | * reference is dropped. The skb is not send to the destination, just all | |
728 | * all error checks are performed and memory in the queue is reserved. | |
729 | * Return values: | |
730 | * < 0: error. skb freed, reference to sock dropped. | |
731 | * 0: continue | |
732 | * 1: repeat lookup - reference dropped while waiting for socket memory. | |
733 | */ | |
a70ea994 AK |
734 | int netlink_attachskb(struct sock *sk, struct sk_buff *skb, int nonblock, |
735 | long timeo, struct sock *ssk) | |
1da177e4 LT |
736 | { |
737 | struct netlink_sock *nlk; | |
738 | ||
739 | nlk = nlk_sk(sk); | |
740 | ||
741 | if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || | |
742 | test_bit(0, &nlk->state)) { | |
743 | DECLARE_WAITQUEUE(wait, current); | |
744 | if (!timeo) { | |
a70ea994 | 745 | if (!ssk || nlk_sk(ssk)->pid == 0) |
1da177e4 LT |
746 | netlink_overrun(sk); |
747 | sock_put(sk); | |
748 | kfree_skb(skb); | |
749 | return -EAGAIN; | |
750 | } | |
751 | ||
752 | __set_current_state(TASK_INTERRUPTIBLE); | |
753 | add_wait_queue(&nlk->wait, &wait); | |
754 | ||
755 | if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || | |
756 | test_bit(0, &nlk->state)) && | |
757 | !sock_flag(sk, SOCK_DEAD)) | |
758 | timeo = schedule_timeout(timeo); | |
759 | ||
760 | __set_current_state(TASK_RUNNING); | |
761 | remove_wait_queue(&nlk->wait, &wait); | |
762 | sock_put(sk); | |
763 | ||
764 | if (signal_pending(current)) { | |
765 | kfree_skb(skb); | |
766 | return sock_intr_errno(timeo); | |
767 | } | |
768 | return 1; | |
769 | } | |
770 | skb_set_owner_r(skb, sk); | |
771 | return 0; | |
772 | } | |
773 | ||
774 | int netlink_sendskb(struct sock *sk, struct sk_buff *skb, int protocol) | |
775 | { | |
1da177e4 LT |
776 | int len = skb->len; |
777 | ||
1da177e4 LT |
778 | skb_queue_tail(&sk->sk_receive_queue, skb); |
779 | sk->sk_data_ready(sk, len); | |
780 | sock_put(sk); | |
781 | return len; | |
782 | } | |
783 | ||
784 | void netlink_detachskb(struct sock *sk, struct sk_buff *skb) | |
785 | { | |
786 | kfree_skb(skb); | |
787 | sock_put(sk); | |
788 | } | |
789 | ||
37da647d | 790 | static inline struct sk_buff *netlink_trim(struct sk_buff *skb, |
dd0fc66f | 791 | gfp_t allocation) |
1da177e4 LT |
792 | { |
793 | int delta; | |
794 | ||
795 | skb_orphan(skb); | |
796 | ||
4305b541 | 797 | delta = skb->end - skb->tail; |
1da177e4 LT |
798 | if (delta * 2 < skb->truesize) |
799 | return skb; | |
800 | ||
801 | if (skb_shared(skb)) { | |
802 | struct sk_buff *nskb = skb_clone(skb, allocation); | |
803 | if (!nskb) | |
804 | return skb; | |
805 | kfree_skb(skb); | |
806 | skb = nskb; | |
807 | } | |
808 | ||
809 | if (!pskb_expand_head(skb, 0, -delta, allocation)) | |
810 | skb->truesize -= delta; | |
811 | ||
812 | return skb; | |
813 | } | |
814 | ||
815 | int netlink_unicast(struct sock *ssk, struct sk_buff *skb, u32 pid, int nonblock) | |
816 | { | |
817 | struct sock *sk; | |
818 | int err; | |
819 | long timeo; | |
820 | ||
821 | skb = netlink_trim(skb, gfp_any()); | |
822 | ||
823 | timeo = sock_sndtimeo(ssk, nonblock); | |
824 | retry: | |
825 | sk = netlink_getsockbypid(ssk, pid); | |
826 | if (IS_ERR(sk)) { | |
827 | kfree_skb(skb); | |
828 | return PTR_ERR(sk); | |
829 | } | |
a70ea994 | 830 | err = netlink_attachskb(sk, skb, nonblock, timeo, ssk); |
1da177e4 LT |
831 | if (err == 1) |
832 | goto retry; | |
833 | if (err) | |
834 | return err; | |
835 | ||
836 | return netlink_sendskb(sk, skb, ssk->sk_protocol); | |
837 | } | |
838 | ||
4277a083 PM |
839 | int netlink_has_listeners(struct sock *sk, unsigned int group) |
840 | { | |
841 | int res = 0; | |
842 | ||
843 | BUG_ON(!(nlk_sk(sk)->flags & NETLINK_KERNEL_SOCKET)); | |
844 | if (group - 1 < nl_table[sk->sk_protocol].groups) | |
845 | res = test_bit(group - 1, nl_table[sk->sk_protocol].listeners); | |
846 | return res; | |
847 | } | |
848 | EXPORT_SYMBOL_GPL(netlink_has_listeners); | |
849 | ||
1da177e4 LT |
850 | static __inline__ int netlink_broadcast_deliver(struct sock *sk, struct sk_buff *skb) |
851 | { | |
852 | struct netlink_sock *nlk = nlk_sk(sk); | |
853 | ||
854 | if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf && | |
855 | !test_bit(0, &nlk->state)) { | |
856 | skb_set_owner_r(skb, sk); | |
857 | skb_queue_tail(&sk->sk_receive_queue, skb); | |
858 | sk->sk_data_ready(sk, skb->len); | |
859 | return atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf; | |
860 | } | |
861 | return -1; | |
862 | } | |
863 | ||
864 | struct netlink_broadcast_data { | |
865 | struct sock *exclude_sk; | |
866 | u32 pid; | |
867 | u32 group; | |
868 | int failure; | |
869 | int congested; | |
870 | int delivered; | |
7d877f3b | 871 | gfp_t allocation; |
1da177e4 LT |
872 | struct sk_buff *skb, *skb2; |
873 | }; | |
874 | ||
875 | static inline int do_one_broadcast(struct sock *sk, | |
876 | struct netlink_broadcast_data *p) | |
877 | { | |
878 | struct netlink_sock *nlk = nlk_sk(sk); | |
879 | int val; | |
880 | ||
881 | if (p->exclude_sk == sk) | |
882 | goto out; | |
883 | ||
f7fa9b10 PM |
884 | if (nlk->pid == p->pid || p->group - 1 >= nlk->ngroups || |
885 | !test_bit(p->group - 1, nlk->groups)) | |
1da177e4 LT |
886 | goto out; |
887 | ||
888 | if (p->failure) { | |
889 | netlink_overrun(sk); | |
890 | goto out; | |
891 | } | |
892 | ||
893 | sock_hold(sk); | |
894 | if (p->skb2 == NULL) { | |
68acc024 | 895 | if (skb_shared(p->skb)) { |
1da177e4 LT |
896 | p->skb2 = skb_clone(p->skb, p->allocation); |
897 | } else { | |
68acc024 TC |
898 | p->skb2 = skb_get(p->skb); |
899 | /* | |
900 | * skb ownership may have been set when | |
901 | * delivered to a previous socket. | |
902 | */ | |
903 | skb_orphan(p->skb2); | |
1da177e4 LT |
904 | } |
905 | } | |
906 | if (p->skb2 == NULL) { | |
907 | netlink_overrun(sk); | |
908 | /* Clone failed. Notify ALL listeners. */ | |
909 | p->failure = 1; | |
910 | } else if ((val = netlink_broadcast_deliver(sk, p->skb2)) < 0) { | |
911 | netlink_overrun(sk); | |
912 | } else { | |
913 | p->congested |= val; | |
914 | p->delivered = 1; | |
915 | p->skb2 = NULL; | |
916 | } | |
917 | sock_put(sk); | |
918 | ||
919 | out: | |
920 | return 0; | |
921 | } | |
922 | ||
923 | int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 pid, | |
dd0fc66f | 924 | u32 group, gfp_t allocation) |
1da177e4 LT |
925 | { |
926 | struct netlink_broadcast_data info; | |
927 | struct hlist_node *node; | |
928 | struct sock *sk; | |
929 | ||
930 | skb = netlink_trim(skb, allocation); | |
931 | ||
932 | info.exclude_sk = ssk; | |
933 | info.pid = pid; | |
934 | info.group = group; | |
935 | info.failure = 0; | |
936 | info.congested = 0; | |
937 | info.delivered = 0; | |
938 | info.allocation = allocation; | |
939 | info.skb = skb; | |
940 | info.skb2 = NULL; | |
941 | ||
942 | /* While we sleep in clone, do not allow to change socket list */ | |
943 | ||
944 | netlink_lock_table(); | |
945 | ||
946 | sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list) | |
947 | do_one_broadcast(sk, &info); | |
948 | ||
aa1c6a6f TC |
949 | kfree_skb(skb); |
950 | ||
1da177e4 LT |
951 | netlink_unlock_table(); |
952 | ||
953 | if (info.skb2) | |
954 | kfree_skb(info.skb2); | |
1da177e4 LT |
955 | |
956 | if (info.delivered) { | |
957 | if (info.congested && (allocation & __GFP_WAIT)) | |
958 | yield(); | |
959 | return 0; | |
960 | } | |
961 | if (info.failure) | |
962 | return -ENOBUFS; | |
963 | return -ESRCH; | |
964 | } | |
965 | ||
966 | struct netlink_set_err_data { | |
967 | struct sock *exclude_sk; | |
968 | u32 pid; | |
969 | u32 group; | |
970 | int code; | |
971 | }; | |
972 | ||
973 | static inline int do_one_set_err(struct sock *sk, | |
974 | struct netlink_set_err_data *p) | |
975 | { | |
976 | struct netlink_sock *nlk = nlk_sk(sk); | |
977 | ||
978 | if (sk == p->exclude_sk) | |
979 | goto out; | |
980 | ||
f7fa9b10 PM |
981 | if (nlk->pid == p->pid || p->group - 1 >= nlk->ngroups || |
982 | !test_bit(p->group - 1, nlk->groups)) | |
1da177e4 LT |
983 | goto out; |
984 | ||
985 | sk->sk_err = p->code; | |
986 | sk->sk_error_report(sk); | |
987 | out: | |
988 | return 0; | |
989 | } | |
990 | ||
991 | void netlink_set_err(struct sock *ssk, u32 pid, u32 group, int code) | |
992 | { | |
993 | struct netlink_set_err_data info; | |
994 | struct hlist_node *node; | |
995 | struct sock *sk; | |
996 | ||
997 | info.exclude_sk = ssk; | |
998 | info.pid = pid; | |
999 | info.group = group; | |
1000 | info.code = code; | |
1001 | ||
1002 | read_lock(&nl_table_lock); | |
1003 | ||
1004 | sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list) | |
1005 | do_one_set_err(sk, &info); | |
1006 | ||
1007 | read_unlock(&nl_table_lock); | |
1008 | } | |
1009 | ||
9a4595bc | 1010 | static int netlink_setsockopt(struct socket *sock, int level, int optname, |
746fac4d | 1011 | char __user *optval, int optlen) |
9a4595bc PM |
1012 | { |
1013 | struct sock *sk = sock->sk; | |
1014 | struct netlink_sock *nlk = nlk_sk(sk); | |
1015 | int val = 0, err; | |
1016 | ||
1017 | if (level != SOL_NETLINK) | |
1018 | return -ENOPROTOOPT; | |
1019 | ||
1020 | if (optlen >= sizeof(int) && | |
1021 | get_user(val, (int __user *)optval)) | |
1022 | return -EFAULT; | |
1023 | ||
1024 | switch (optname) { | |
1025 | case NETLINK_PKTINFO: | |
1026 | if (val) | |
1027 | nlk->flags |= NETLINK_RECV_PKTINFO; | |
1028 | else | |
1029 | nlk->flags &= ~NETLINK_RECV_PKTINFO; | |
1030 | err = 0; | |
1031 | break; | |
1032 | case NETLINK_ADD_MEMBERSHIP: | |
1033 | case NETLINK_DROP_MEMBERSHIP: { | |
1034 | unsigned int subscriptions; | |
1035 | int old, new = optname == NETLINK_ADD_MEMBERSHIP ? 1 : 0; | |
1036 | ||
1037 | if (!netlink_capable(sock, NL_NONROOT_RECV)) | |
1038 | return -EPERM; | |
513c2500 PM |
1039 | if (nlk->groups == NULL) { |
1040 | err = netlink_alloc_groups(sk); | |
1041 | if (err) | |
1042 | return err; | |
1043 | } | |
9a4595bc PM |
1044 | if (!val || val - 1 >= nlk->ngroups) |
1045 | return -EINVAL; | |
1046 | netlink_table_grab(); | |
1047 | old = test_bit(val - 1, nlk->groups); | |
1048 | subscriptions = nlk->subscriptions - old + new; | |
1049 | if (new) | |
1050 | __set_bit(val - 1, nlk->groups); | |
1051 | else | |
1052 | __clear_bit(val - 1, nlk->groups); | |
1053 | netlink_update_subscriptions(sk, subscriptions); | |
4277a083 | 1054 | netlink_update_listeners(sk); |
9a4595bc PM |
1055 | netlink_table_ungrab(); |
1056 | err = 0; | |
1057 | break; | |
1058 | } | |
1059 | default: | |
1060 | err = -ENOPROTOOPT; | |
1061 | } | |
1062 | return err; | |
1063 | } | |
1064 | ||
1065 | static int netlink_getsockopt(struct socket *sock, int level, int optname, | |
746fac4d | 1066 | char __user *optval, int __user *optlen) |
9a4595bc PM |
1067 | { |
1068 | struct sock *sk = sock->sk; | |
1069 | struct netlink_sock *nlk = nlk_sk(sk); | |
1070 | int len, val, err; | |
1071 | ||
1072 | if (level != SOL_NETLINK) | |
1073 | return -ENOPROTOOPT; | |
1074 | ||
1075 | if (get_user(len, optlen)) | |
1076 | return -EFAULT; | |
1077 | if (len < 0) | |
1078 | return -EINVAL; | |
1079 | ||
1080 | switch (optname) { | |
1081 | case NETLINK_PKTINFO: | |
1082 | if (len < sizeof(int)) | |
1083 | return -EINVAL; | |
1084 | len = sizeof(int); | |
1085 | val = nlk->flags & NETLINK_RECV_PKTINFO ? 1 : 0; | |
a27b58fe HC |
1086 | if (put_user(len, optlen) || |
1087 | put_user(val, optval)) | |
1088 | return -EFAULT; | |
9a4595bc PM |
1089 | err = 0; |
1090 | break; | |
1091 | default: | |
1092 | err = -ENOPROTOOPT; | |
1093 | } | |
1094 | return err; | |
1095 | } | |
1096 | ||
1097 | static void netlink_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb) | |
1098 | { | |
1099 | struct nl_pktinfo info; | |
1100 | ||
1101 | info.group = NETLINK_CB(skb).dst_group; | |
1102 | put_cmsg(msg, SOL_NETLINK, NETLINK_PKTINFO, sizeof(info), &info); | |
1103 | } | |
1104 | ||
1da177e4 LT |
1105 | static inline void netlink_rcv_wake(struct sock *sk) |
1106 | { | |
1107 | struct netlink_sock *nlk = nlk_sk(sk); | |
1108 | ||
b03efcfb | 1109 | if (skb_queue_empty(&sk->sk_receive_queue)) |
1da177e4 LT |
1110 | clear_bit(0, &nlk->state); |
1111 | if (!test_bit(0, &nlk->state)) | |
1112 | wake_up_interruptible(&nlk->wait); | |
1113 | } | |
1114 | ||
1115 | static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock, | |
1116 | struct msghdr *msg, size_t len) | |
1117 | { | |
1118 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1119 | struct sock *sk = sock->sk; | |
1120 | struct netlink_sock *nlk = nlk_sk(sk); | |
1121 | struct sockaddr_nl *addr=msg->msg_name; | |
1122 | u32 dst_pid; | |
d629b836 | 1123 | u32 dst_group; |
1da177e4 LT |
1124 | struct sk_buff *skb; |
1125 | int err; | |
1126 | struct scm_cookie scm; | |
1127 | ||
1128 | if (msg->msg_flags&MSG_OOB) | |
1129 | return -EOPNOTSUPP; | |
1130 | ||
1131 | if (NULL == siocb->scm) | |
1132 | siocb->scm = &scm; | |
1133 | err = scm_send(sock, msg, siocb->scm); | |
1134 | if (err < 0) | |
1135 | return err; | |
1136 | ||
1137 | if (msg->msg_namelen) { | |
1138 | if (addr->nl_family != AF_NETLINK) | |
1139 | return -EINVAL; | |
1140 | dst_pid = addr->nl_pid; | |
d629b836 PM |
1141 | dst_group = ffs(addr->nl_groups); |
1142 | if (dst_group && !netlink_capable(sock, NL_NONROOT_SEND)) | |
1da177e4 LT |
1143 | return -EPERM; |
1144 | } else { | |
1145 | dst_pid = nlk->dst_pid; | |
d629b836 | 1146 | dst_group = nlk->dst_group; |
1da177e4 LT |
1147 | } |
1148 | ||
1149 | if (!nlk->pid) { | |
1150 | err = netlink_autobind(sock); | |
1151 | if (err) | |
1152 | goto out; | |
1153 | } | |
1154 | ||
1155 | err = -EMSGSIZE; | |
1156 | if (len > sk->sk_sndbuf - 32) | |
1157 | goto out; | |
1158 | err = -ENOBUFS; | |
339bf98f | 1159 | skb = alloc_skb(len, GFP_KERNEL); |
1da177e4 LT |
1160 | if (skb==NULL) |
1161 | goto out; | |
1162 | ||
1163 | NETLINK_CB(skb).pid = nlk->pid; | |
d629b836 | 1164 | NETLINK_CB(skb).dst_group = dst_group; |
c94c257c | 1165 | NETLINK_CB(skb).loginuid = audit_get_loginuid(current->audit_context); |
e7c34970 | 1166 | selinux_get_task_sid(current, &(NETLINK_CB(skb).sid)); |
1da177e4 LT |
1167 | memcpy(NETLINK_CREDS(skb), &siocb->scm->creds, sizeof(struct ucred)); |
1168 | ||
1169 | /* What can I do? Netlink is asynchronous, so that | |
1170 | we will have to save current capabilities to | |
1171 | check them, when this message will be delivered | |
1172 | to corresponding kernel module. --ANK (980802) | |
1173 | */ | |
1174 | ||
1175 | err = -EFAULT; | |
1176 | if (memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len)) { | |
1177 | kfree_skb(skb); | |
1178 | goto out; | |
1179 | } | |
1180 | ||
1181 | err = security_netlink_send(sk, skb); | |
1182 | if (err) { | |
1183 | kfree_skb(skb); | |
1184 | goto out; | |
1185 | } | |
1186 | ||
d629b836 | 1187 | if (dst_group) { |
1da177e4 | 1188 | atomic_inc(&skb->users); |
d629b836 | 1189 | netlink_broadcast(sk, skb, dst_pid, dst_group, GFP_KERNEL); |
1da177e4 LT |
1190 | } |
1191 | err = netlink_unicast(sk, skb, dst_pid, msg->msg_flags&MSG_DONTWAIT); | |
1192 | ||
1193 | out: | |
1194 | return err; | |
1195 | } | |
1196 | ||
1197 | static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock, | |
1198 | struct msghdr *msg, size_t len, | |
1199 | int flags) | |
1200 | { | |
1201 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1202 | struct scm_cookie scm; | |
1203 | struct sock *sk = sock->sk; | |
1204 | struct netlink_sock *nlk = nlk_sk(sk); | |
1205 | int noblock = flags&MSG_DONTWAIT; | |
1206 | size_t copied; | |
1207 | struct sk_buff *skb; | |
1208 | int err; | |
1209 | ||
1210 | if (flags&MSG_OOB) | |
1211 | return -EOPNOTSUPP; | |
1212 | ||
1213 | copied = 0; | |
1214 | ||
1215 | skb = skb_recv_datagram(sk,flags,noblock,&err); | |
1216 | if (skb==NULL) | |
1217 | goto out; | |
1218 | ||
1219 | msg->msg_namelen = 0; | |
1220 | ||
1221 | copied = skb->len; | |
1222 | if (len < copied) { | |
1223 | msg->msg_flags |= MSG_TRUNC; | |
1224 | copied = len; | |
1225 | } | |
1226 | ||
badff6d0 | 1227 | skb_reset_transport_header(skb); |
1da177e4 LT |
1228 | err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); |
1229 | ||
1230 | if (msg->msg_name) { | |
1231 | struct sockaddr_nl *addr = (struct sockaddr_nl*)msg->msg_name; | |
1232 | addr->nl_family = AF_NETLINK; | |
1233 | addr->nl_pad = 0; | |
1234 | addr->nl_pid = NETLINK_CB(skb).pid; | |
d629b836 | 1235 | addr->nl_groups = netlink_group_mask(NETLINK_CB(skb).dst_group); |
1da177e4 LT |
1236 | msg->msg_namelen = sizeof(*addr); |
1237 | } | |
1238 | ||
cc9a06cd PM |
1239 | if (nlk->flags & NETLINK_RECV_PKTINFO) |
1240 | netlink_cmsg_recv_pktinfo(msg, skb); | |
1241 | ||
1da177e4 LT |
1242 | if (NULL == siocb->scm) { |
1243 | memset(&scm, 0, sizeof(scm)); | |
1244 | siocb->scm = &scm; | |
1245 | } | |
1246 | siocb->scm->creds = *NETLINK_CREDS(skb); | |
188ccb55 PM |
1247 | if (flags & MSG_TRUNC) |
1248 | copied = skb->len; | |
1da177e4 LT |
1249 | skb_free_datagram(sk, skb); |
1250 | ||
1251 | if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) | |
1252 | netlink_dump(sk); | |
1253 | ||
1254 | scm_recv(sock, msg, siocb->scm, flags); | |
1da177e4 LT |
1255 | out: |
1256 | netlink_rcv_wake(sk); | |
1257 | return err ? : copied; | |
1258 | } | |
1259 | ||
1260 | static void netlink_data_ready(struct sock *sk, int len) | |
1261 | { | |
1262 | struct netlink_sock *nlk = nlk_sk(sk); | |
1263 | ||
1264 | if (nlk->data_ready) | |
1265 | nlk->data_ready(sk, len); | |
1266 | netlink_rcv_wake(sk); | |
1267 | } | |
1268 | ||
1269 | /* | |
746fac4d | 1270 | * We export these functions to other modules. They provide a |
1da177e4 LT |
1271 | * complete set of kernel non-blocking support for message |
1272 | * queueing. | |
1273 | */ | |
1274 | ||
1275 | struct sock * | |
06628607 | 1276 | netlink_kernel_create(int unit, unsigned int groups, |
746fac4d | 1277 | void (*input)(struct sock *sk, int len), |
af65bdfc | 1278 | struct mutex *cb_mutex, struct module *module) |
1da177e4 LT |
1279 | { |
1280 | struct socket *sock; | |
1281 | struct sock *sk; | |
77247bbb | 1282 | struct netlink_sock *nlk; |
4277a083 | 1283 | unsigned long *listeners = NULL; |
1da177e4 | 1284 | |
fab2caf6 | 1285 | BUG_ON(!nl_table); |
1da177e4 LT |
1286 | |
1287 | if (unit<0 || unit>=MAX_LINKS) | |
1288 | return NULL; | |
1289 | ||
1290 | if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock)) | |
1291 | return NULL; | |
1292 | ||
af65bdfc | 1293 | if (__netlink_create(sock, cb_mutex, unit) < 0) |
77247bbb | 1294 | goto out_sock_release; |
4fdb3bb7 | 1295 | |
4277a083 PM |
1296 | if (groups < 32) |
1297 | groups = 32; | |
1298 | ||
1299 | listeners = kzalloc(NLGRPSZ(groups), GFP_KERNEL); | |
1300 | if (!listeners) | |
1301 | goto out_sock_release; | |
1302 | ||
1da177e4 LT |
1303 | sk = sock->sk; |
1304 | sk->sk_data_ready = netlink_data_ready; | |
1305 | if (input) | |
1306 | nlk_sk(sk)->data_ready = input; | |
1307 | ||
77247bbb PM |
1308 | if (netlink_insert(sk, 0)) |
1309 | goto out_sock_release; | |
4fdb3bb7 | 1310 | |
77247bbb PM |
1311 | nlk = nlk_sk(sk); |
1312 | nlk->flags |= NETLINK_KERNEL_SOCKET; | |
4fdb3bb7 | 1313 | |
4fdb3bb7 | 1314 | netlink_table_grab(); |
4277a083 PM |
1315 | nl_table[unit].groups = groups; |
1316 | nl_table[unit].listeners = listeners; | |
af65bdfc | 1317 | nl_table[unit].cb_mutex = cb_mutex; |
77247bbb | 1318 | nl_table[unit].module = module; |
ab33a171 | 1319 | nl_table[unit].registered = 1; |
4fdb3bb7 | 1320 | netlink_table_ungrab(); |
77247bbb PM |
1321 | |
1322 | return sk; | |
1323 | ||
4fdb3bb7 | 1324 | out_sock_release: |
4277a083 | 1325 | kfree(listeners); |
4fdb3bb7 | 1326 | sock_release(sock); |
77247bbb | 1327 | return NULL; |
1da177e4 LT |
1328 | } |
1329 | ||
1330 | void netlink_set_nonroot(int protocol, unsigned int flags) | |
746fac4d YH |
1331 | { |
1332 | if ((unsigned int)protocol < MAX_LINKS) | |
1da177e4 | 1333 | nl_table[protocol].nl_nonroot = flags; |
746fac4d | 1334 | } |
1da177e4 LT |
1335 | |
1336 | static void netlink_destroy_callback(struct netlink_callback *cb) | |
1337 | { | |
1338 | if (cb->skb) | |
1339 | kfree_skb(cb->skb); | |
1340 | kfree(cb); | |
1341 | } | |
1342 | ||
1343 | /* | |
1344 | * It looks a bit ugly. | |
1345 | * It would be better to create kernel thread. | |
1346 | */ | |
1347 | ||
1348 | static int netlink_dump(struct sock *sk) | |
1349 | { | |
1350 | struct netlink_sock *nlk = nlk_sk(sk); | |
1351 | struct netlink_callback *cb; | |
1352 | struct sk_buff *skb; | |
1353 | struct nlmsghdr *nlh; | |
bf8b79e4 | 1354 | int len, err = -ENOBUFS; |
746fac4d | 1355 | |
1da177e4 LT |
1356 | skb = sock_rmalloc(sk, NLMSG_GOODSIZE, 0, GFP_KERNEL); |
1357 | if (!skb) | |
bf8b79e4 | 1358 | goto errout; |
1da177e4 | 1359 | |
af65bdfc | 1360 | mutex_lock(nlk->cb_mutex); |
1da177e4 LT |
1361 | |
1362 | cb = nlk->cb; | |
1363 | if (cb == NULL) { | |
bf8b79e4 TG |
1364 | err = -EINVAL; |
1365 | goto errout_skb; | |
1da177e4 LT |
1366 | } |
1367 | ||
1368 | len = cb->dump(skb, cb); | |
1369 | ||
1370 | if (len > 0) { | |
af65bdfc | 1371 | mutex_unlock(nlk->cb_mutex); |
1da177e4 LT |
1372 | skb_queue_tail(&sk->sk_receive_queue, skb); |
1373 | sk->sk_data_ready(sk, len); | |
1374 | return 0; | |
1375 | } | |
1376 | ||
bf8b79e4 TG |
1377 | nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI); |
1378 | if (!nlh) | |
1379 | goto errout_skb; | |
1380 | ||
1381 | memcpy(nlmsg_data(nlh), &len, sizeof(len)); | |
1382 | ||
1da177e4 LT |
1383 | skb_queue_tail(&sk->sk_receive_queue, skb); |
1384 | sk->sk_data_ready(sk, skb->len); | |
1385 | ||
a8f74b22 TG |
1386 | if (cb->done) |
1387 | cb->done(cb); | |
1da177e4 | 1388 | nlk->cb = NULL; |
af65bdfc | 1389 | mutex_unlock(nlk->cb_mutex); |
1da177e4 LT |
1390 | |
1391 | netlink_destroy_callback(cb); | |
1da177e4 | 1392 | return 0; |
1797754e | 1393 | |
bf8b79e4 | 1394 | errout_skb: |
af65bdfc | 1395 | mutex_unlock(nlk->cb_mutex); |
bf8b79e4 TG |
1396 | kfree_skb(skb); |
1397 | errout: | |
1398 | return err; | |
1da177e4 LT |
1399 | } |
1400 | ||
1401 | int netlink_dump_start(struct sock *ssk, struct sk_buff *skb, | |
1402 | struct nlmsghdr *nlh, | |
1403 | int (*dump)(struct sk_buff *skb, struct netlink_callback*), | |
1404 | int (*done)(struct netlink_callback*)) | |
1405 | { | |
1406 | struct netlink_callback *cb; | |
1407 | struct sock *sk; | |
1408 | struct netlink_sock *nlk; | |
1409 | ||
0da974f4 | 1410 | cb = kzalloc(sizeof(*cb), GFP_KERNEL); |
1da177e4 LT |
1411 | if (cb == NULL) |
1412 | return -ENOBUFS; | |
1413 | ||
1da177e4 LT |
1414 | cb->dump = dump; |
1415 | cb->done = done; | |
1416 | cb->nlh = nlh; | |
1417 | atomic_inc(&skb->users); | |
1418 | cb->skb = skb; | |
1419 | ||
1420 | sk = netlink_lookup(ssk->sk_protocol, NETLINK_CB(skb).pid); | |
1421 | if (sk == NULL) { | |
1422 | netlink_destroy_callback(cb); | |
1423 | return -ECONNREFUSED; | |
1424 | } | |
1425 | nlk = nlk_sk(sk); | |
3f660d66 | 1426 | /* A dump is in progress... */ |
af65bdfc | 1427 | mutex_lock(nlk->cb_mutex); |
3f660d66 | 1428 | if (nlk->cb) { |
af65bdfc | 1429 | mutex_unlock(nlk->cb_mutex); |
1da177e4 LT |
1430 | netlink_destroy_callback(cb); |
1431 | sock_put(sk); | |
1432 | return -EBUSY; | |
1433 | } | |
1434 | nlk->cb = cb; | |
af65bdfc | 1435 | mutex_unlock(nlk->cb_mutex); |
1da177e4 LT |
1436 | |
1437 | netlink_dump(sk); | |
1438 | sock_put(sk); | |
c702e804 TG |
1439 | |
1440 | /* We successfully started a dump, by returning -EINTR we | |
1441 | * signal the queue mangement to interrupt processing of | |
1442 | * any netlink messages so userspace gets a chance to read | |
1443 | * the results. */ | |
1444 | return -EINTR; | |
1da177e4 LT |
1445 | } |
1446 | ||
1447 | void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err) | |
1448 | { | |
1449 | struct sk_buff *skb; | |
1450 | struct nlmsghdr *rep; | |
1451 | struct nlmsgerr *errmsg; | |
339bf98f | 1452 | size_t payload = sizeof(*errmsg); |
1da177e4 | 1453 | |
339bf98f TG |
1454 | /* error messages get the original request appened */ |
1455 | if (err) | |
1456 | payload += nlmsg_len(nlh); | |
1da177e4 | 1457 | |
339bf98f | 1458 | skb = nlmsg_new(payload, GFP_KERNEL); |
1da177e4 LT |
1459 | if (!skb) { |
1460 | struct sock *sk; | |
1461 | ||
1462 | sk = netlink_lookup(in_skb->sk->sk_protocol, | |
1463 | NETLINK_CB(in_skb).pid); | |
1464 | if (sk) { | |
1465 | sk->sk_err = ENOBUFS; | |
1466 | sk->sk_error_report(sk); | |
1467 | sock_put(sk); | |
1468 | } | |
1469 | return; | |
1470 | } | |
1471 | ||
1472 | rep = __nlmsg_put(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, | |
1797754e | 1473 | NLMSG_ERROR, sizeof(struct nlmsgerr), 0); |
bf8b79e4 | 1474 | errmsg = nlmsg_data(rep); |
1da177e4 | 1475 | errmsg->error = err; |
bf8b79e4 | 1476 | memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(*nlh)); |
1da177e4 LT |
1477 | netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).pid, MSG_DONTWAIT); |
1478 | } | |
1479 | ||
82ace47a | 1480 | static int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *, |
1d00a4eb | 1481 | struct nlmsghdr *)) |
82ace47a | 1482 | { |
82ace47a TG |
1483 | struct nlmsghdr *nlh; |
1484 | int err; | |
1485 | ||
1486 | while (skb->len >= nlmsg_total_size(0)) { | |
b529ccf2 | 1487 | nlh = nlmsg_hdr(skb); |
d35b6856 | 1488 | err = 0; |
82ace47a | 1489 | |
ad8e4b75 | 1490 | if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len) |
82ace47a TG |
1491 | return 0; |
1492 | ||
d35b6856 TG |
1493 | /* Only requests are handled by the kernel */ |
1494 | if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) | |
1495 | goto skip; | |
45e7ae7f TG |
1496 | |
1497 | /* Skip control messages */ | |
1498 | if (nlh->nlmsg_type < NLMSG_MIN_TYPE) | |
1499 | goto skip; | |
d35b6856 | 1500 | |
1d00a4eb TG |
1501 | err = cb(skb, nlh); |
1502 | if (err == -EINTR) { | |
1503 | /* Not an error, but we interrupt processing */ | |
1504 | netlink_queue_skip(nlh, skb); | |
1505 | return err; | |
d35b6856 TG |
1506 | } |
1507 | skip: | |
1508 | if (nlh->nlmsg_flags & NLM_F_ACK || err) | |
82ace47a | 1509 | netlink_ack(skb, nlh, err); |
82ace47a | 1510 | |
bf8b79e4 | 1511 | netlink_queue_skip(nlh, skb); |
82ace47a TG |
1512 | } |
1513 | ||
1514 | return 0; | |
1515 | } | |
1516 | ||
1517 | /** | |
1518 | * nelink_run_queue - Process netlink receive queue. | |
1519 | * @sk: Netlink socket containing the queue | |
1520 | * @qlen: Place to store queue length upon entry | |
1521 | * @cb: Callback function invoked for each netlink message found | |
1522 | * | |
1523 | * Processes as much as there was in the queue upon entry and invokes | |
1524 | * a callback function for each netlink message found. The callback | |
1525 | * function may refuse a message by returning a negative error code | |
1526 | * but setting the error pointer to 0 in which case this function | |
1527 | * returns with a qlen != 0. | |
1528 | * | |
1529 | * qlen must be initialized to 0 before the initial entry, afterwards | |
1530 | * the function may be called repeatedly until qlen reaches 0. | |
1d00a4eb TG |
1531 | * |
1532 | * The callback function may return -EINTR to signal that processing | |
1533 | * of netlink messages shall be interrupted. In this case the message | |
1534 | * currently being processed will NOT be requeued onto the receive | |
1535 | * queue. | |
82ace47a TG |
1536 | */ |
1537 | void netlink_run_queue(struct sock *sk, unsigned int *qlen, | |
1d00a4eb | 1538 | int (*cb)(struct sk_buff *, struct nlmsghdr *)) |
82ace47a TG |
1539 | { |
1540 | struct sk_buff *skb; | |
1541 | ||
1542 | if (!*qlen || *qlen > skb_queue_len(&sk->sk_receive_queue)) | |
1543 | *qlen = skb_queue_len(&sk->sk_receive_queue); | |
1544 | ||
1545 | for (; *qlen; (*qlen)--) { | |
1546 | skb = skb_dequeue(&sk->sk_receive_queue); | |
1547 | if (netlink_rcv_skb(skb, cb)) { | |
1548 | if (skb->len) | |
1549 | skb_queue_head(&sk->sk_receive_queue, skb); | |
1550 | else { | |
1551 | kfree_skb(skb); | |
1552 | (*qlen)--; | |
1553 | } | |
1554 | break; | |
1555 | } | |
1556 | ||
1557 | kfree_skb(skb); | |
1558 | } | |
1559 | } | |
1560 | ||
1561 | /** | |
1562 | * netlink_queue_skip - Skip netlink message while processing queue. | |
1563 | * @nlh: Netlink message to be skipped | |
1564 | * @skb: Socket buffer containing the netlink messages. | |
1565 | * | |
1566 | * Pulls the given netlink message off the socket buffer so the next | |
1567 | * call to netlink_queue_run() will not reconsider the message. | |
1568 | */ | |
42bad1da | 1569 | static void netlink_queue_skip(struct nlmsghdr *nlh, struct sk_buff *skb) |
82ace47a TG |
1570 | { |
1571 | int msglen = NLMSG_ALIGN(nlh->nlmsg_len); | |
1572 | ||
1573 | if (msglen > skb->len) | |
1574 | msglen = skb->len; | |
1575 | ||
1576 | skb_pull(skb, msglen); | |
1577 | } | |
1da177e4 | 1578 | |
d387f6ad TG |
1579 | /** |
1580 | * nlmsg_notify - send a notification netlink message | |
1581 | * @sk: netlink socket to use | |
1582 | * @skb: notification message | |
1583 | * @pid: destination netlink pid for reports or 0 | |
1584 | * @group: destination multicast group or 0 | |
1585 | * @report: 1 to report back, 0 to disable | |
1586 | * @flags: allocation flags | |
1587 | */ | |
1588 | int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 pid, | |
1589 | unsigned int group, int report, gfp_t flags) | |
1590 | { | |
1591 | int err = 0; | |
1592 | ||
1593 | if (group) { | |
1594 | int exclude_pid = 0; | |
1595 | ||
1596 | if (report) { | |
1597 | atomic_inc(&skb->users); | |
1598 | exclude_pid = pid; | |
1599 | } | |
1600 | ||
1601 | /* errors reported via destination sk->sk_err */ | |
1602 | nlmsg_multicast(sk, skb, exclude_pid, group, flags); | |
1603 | } | |
1604 | ||
1605 | if (report) | |
1606 | err = nlmsg_unicast(sk, skb, pid); | |
1607 | ||
1608 | return err; | |
1609 | } | |
1610 | ||
1da177e4 LT |
1611 | #ifdef CONFIG_PROC_FS |
1612 | struct nl_seq_iter { | |
1613 | int link; | |
1614 | int hash_idx; | |
1615 | }; | |
1616 | ||
1617 | static struct sock *netlink_seq_socket_idx(struct seq_file *seq, loff_t pos) | |
1618 | { | |
1619 | struct nl_seq_iter *iter = seq->private; | |
1620 | int i, j; | |
1621 | struct sock *s; | |
1622 | struct hlist_node *node; | |
1623 | loff_t off = 0; | |
1624 | ||
1625 | for (i=0; i<MAX_LINKS; i++) { | |
1626 | struct nl_pid_hash *hash = &nl_table[i].hash; | |
1627 | ||
1628 | for (j = 0; j <= hash->mask; j++) { | |
1629 | sk_for_each(s, node, &hash->table[j]) { | |
1630 | if (off == pos) { | |
1631 | iter->link = i; | |
1632 | iter->hash_idx = j; | |
1633 | return s; | |
1634 | } | |
1635 | ++off; | |
1636 | } | |
1637 | } | |
1638 | } | |
1639 | return NULL; | |
1640 | } | |
1641 | ||
1642 | static void *netlink_seq_start(struct seq_file *seq, loff_t *pos) | |
1643 | { | |
1644 | read_lock(&nl_table_lock); | |
1645 | return *pos ? netlink_seq_socket_idx(seq, *pos - 1) : SEQ_START_TOKEN; | |
1646 | } | |
1647 | ||
1648 | static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
1649 | { | |
1650 | struct sock *s; | |
1651 | struct nl_seq_iter *iter; | |
1652 | int i, j; | |
1653 | ||
1654 | ++*pos; | |
1655 | ||
1656 | if (v == SEQ_START_TOKEN) | |
1657 | return netlink_seq_socket_idx(seq, 0); | |
746fac4d | 1658 | |
1da177e4 LT |
1659 | s = sk_next(v); |
1660 | if (s) | |
1661 | return s; | |
1662 | ||
1663 | iter = seq->private; | |
1664 | i = iter->link; | |
1665 | j = iter->hash_idx + 1; | |
1666 | ||
1667 | do { | |
1668 | struct nl_pid_hash *hash = &nl_table[i].hash; | |
1669 | ||
1670 | for (; j <= hash->mask; j++) { | |
1671 | s = sk_head(&hash->table[j]); | |
1672 | if (s) { | |
1673 | iter->link = i; | |
1674 | iter->hash_idx = j; | |
1675 | return s; | |
1676 | } | |
1677 | } | |
1678 | ||
1679 | j = 0; | |
1680 | } while (++i < MAX_LINKS); | |
1681 | ||
1682 | return NULL; | |
1683 | } | |
1684 | ||
1685 | static void netlink_seq_stop(struct seq_file *seq, void *v) | |
1686 | { | |
1687 | read_unlock(&nl_table_lock); | |
1688 | } | |
1689 | ||
1690 | ||
1691 | static int netlink_seq_show(struct seq_file *seq, void *v) | |
1692 | { | |
1693 | if (v == SEQ_START_TOKEN) | |
1694 | seq_puts(seq, | |
1695 | "sk Eth Pid Groups " | |
1696 | "Rmem Wmem Dump Locks\n"); | |
1697 | else { | |
1698 | struct sock *s = v; | |
1699 | struct netlink_sock *nlk = nlk_sk(s); | |
1700 | ||
1701 | seq_printf(seq, "%p %-3d %-6d %08x %-8d %-8d %p %d\n", | |
1702 | s, | |
1703 | s->sk_protocol, | |
1704 | nlk->pid, | |
513c2500 | 1705 | nlk->groups ? (u32)nlk->groups[0] : 0, |
1da177e4 LT |
1706 | atomic_read(&s->sk_rmem_alloc), |
1707 | atomic_read(&s->sk_wmem_alloc), | |
1708 | nlk->cb, | |
1709 | atomic_read(&s->sk_refcnt) | |
1710 | ); | |
1711 | ||
1712 | } | |
1713 | return 0; | |
1714 | } | |
1715 | ||
56b3d975 | 1716 | static const struct seq_operations netlink_seq_ops = { |
1da177e4 LT |
1717 | .start = netlink_seq_start, |
1718 | .next = netlink_seq_next, | |
1719 | .stop = netlink_seq_stop, | |
1720 | .show = netlink_seq_show, | |
1721 | }; | |
1722 | ||
1723 | ||
1724 | static int netlink_seq_open(struct inode *inode, struct file *file) | |
1725 | { | |
1726 | struct seq_file *seq; | |
1727 | struct nl_seq_iter *iter; | |
1728 | int err; | |
1729 | ||
0da974f4 | 1730 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1da177e4 LT |
1731 | if (!iter) |
1732 | return -ENOMEM; | |
1733 | ||
1734 | err = seq_open(file, &netlink_seq_ops); | |
1735 | if (err) { | |
1736 | kfree(iter); | |
1737 | return err; | |
1738 | } | |
1739 | ||
1da177e4 LT |
1740 | seq = file->private_data; |
1741 | seq->private = iter; | |
1742 | return 0; | |
1743 | } | |
1744 | ||
da7071d7 | 1745 | static const struct file_operations netlink_seq_fops = { |
1da177e4 LT |
1746 | .owner = THIS_MODULE, |
1747 | .open = netlink_seq_open, | |
1748 | .read = seq_read, | |
1749 | .llseek = seq_lseek, | |
1750 | .release = seq_release_private, | |
1751 | }; | |
1752 | ||
1753 | #endif | |
1754 | ||
1755 | int netlink_register_notifier(struct notifier_block *nb) | |
1756 | { | |
e041c683 | 1757 | return atomic_notifier_chain_register(&netlink_chain, nb); |
1da177e4 LT |
1758 | } |
1759 | ||
1760 | int netlink_unregister_notifier(struct notifier_block *nb) | |
1761 | { | |
e041c683 | 1762 | return atomic_notifier_chain_unregister(&netlink_chain, nb); |
1da177e4 | 1763 | } |
746fac4d | 1764 | |
90ddc4f0 | 1765 | static const struct proto_ops netlink_ops = { |
1da177e4 LT |
1766 | .family = PF_NETLINK, |
1767 | .owner = THIS_MODULE, | |
1768 | .release = netlink_release, | |
1769 | .bind = netlink_bind, | |
1770 | .connect = netlink_connect, | |
1771 | .socketpair = sock_no_socketpair, | |
1772 | .accept = sock_no_accept, | |
1773 | .getname = netlink_getname, | |
1774 | .poll = datagram_poll, | |
1775 | .ioctl = sock_no_ioctl, | |
1776 | .listen = sock_no_listen, | |
1777 | .shutdown = sock_no_shutdown, | |
9a4595bc PM |
1778 | .setsockopt = netlink_setsockopt, |
1779 | .getsockopt = netlink_getsockopt, | |
1da177e4 LT |
1780 | .sendmsg = netlink_sendmsg, |
1781 | .recvmsg = netlink_recvmsg, | |
1782 | .mmap = sock_no_mmap, | |
1783 | .sendpage = sock_no_sendpage, | |
1784 | }; | |
1785 | ||
1786 | static struct net_proto_family netlink_family_ops = { | |
1787 | .family = PF_NETLINK, | |
1788 | .create = netlink_create, | |
1789 | .owner = THIS_MODULE, /* for consistency 8) */ | |
1790 | }; | |
1791 | ||
1da177e4 LT |
1792 | static int __init netlink_proto_init(void) |
1793 | { | |
1794 | struct sk_buff *dummy_skb; | |
1795 | int i; | |
1796 | unsigned long max; | |
1797 | unsigned int order; | |
1798 | int err = proto_register(&netlink_proto, 0); | |
1799 | ||
1800 | if (err != 0) | |
1801 | goto out; | |
1802 | ||
ef047f5e | 1803 | BUILD_BUG_ON(sizeof(struct netlink_skb_parms) > sizeof(dummy_skb->cb)); |
1da177e4 | 1804 | |
0da974f4 | 1805 | nl_table = kcalloc(MAX_LINKS, sizeof(*nl_table), GFP_KERNEL); |
fab2caf6 AM |
1806 | if (!nl_table) |
1807 | goto panic; | |
1da177e4 | 1808 | |
1da177e4 LT |
1809 | if (num_physpages >= (128 * 1024)) |
1810 | max = num_physpages >> (21 - PAGE_SHIFT); | |
1811 | else | |
1812 | max = num_physpages >> (23 - PAGE_SHIFT); | |
1813 | ||
1814 | order = get_bitmask_order(max) - 1 + PAGE_SHIFT; | |
1815 | max = (1UL << order) / sizeof(struct hlist_head); | |
1816 | order = get_bitmask_order(max > UINT_MAX ? UINT_MAX : max) - 1; | |
1817 | ||
1818 | for (i = 0; i < MAX_LINKS; i++) { | |
1819 | struct nl_pid_hash *hash = &nl_table[i].hash; | |
1820 | ||
1821 | hash->table = nl_pid_hash_alloc(1 * sizeof(*hash->table)); | |
1822 | if (!hash->table) { | |
1823 | while (i-- > 0) | |
1824 | nl_pid_hash_free(nl_table[i].hash.table, | |
1825 | 1 * sizeof(*hash->table)); | |
1826 | kfree(nl_table); | |
fab2caf6 | 1827 | goto panic; |
1da177e4 LT |
1828 | } |
1829 | memset(hash->table, 0, 1 * sizeof(*hash->table)); | |
1830 | hash->max_shift = order; | |
1831 | hash->shift = 0; | |
1832 | hash->mask = 0; | |
1833 | hash->rehash_time = jiffies; | |
1834 | } | |
1835 | ||
1836 | sock_register(&netlink_family_ops); | |
1837 | #ifdef CONFIG_PROC_FS | |
1838 | proc_net_fops_create("netlink", 0, &netlink_seq_fops); | |
1839 | #endif | |
746fac4d | 1840 | /* The netlink device handler may be needed early. */ |
1da177e4 LT |
1841 | rtnetlink_init(); |
1842 | out: | |
1843 | return err; | |
fab2caf6 AM |
1844 | panic: |
1845 | panic("netlink_init: Cannot allocate nl_table\n"); | |
1da177e4 LT |
1846 | } |
1847 | ||
1da177e4 | 1848 | core_initcall(netlink_proto_init); |
1da177e4 LT |
1849 | |
1850 | EXPORT_SYMBOL(netlink_ack); | |
82ace47a | 1851 | EXPORT_SYMBOL(netlink_run_queue); |
1da177e4 LT |
1852 | EXPORT_SYMBOL(netlink_broadcast); |
1853 | EXPORT_SYMBOL(netlink_dump_start); | |
1854 | EXPORT_SYMBOL(netlink_kernel_create); | |
1855 | EXPORT_SYMBOL(netlink_register_notifier); | |
1da177e4 LT |
1856 | EXPORT_SYMBOL(netlink_set_nonroot); |
1857 | EXPORT_SYMBOL(netlink_unicast); | |
1858 | EXPORT_SYMBOL(netlink_unregister_notifier); | |
d387f6ad | 1859 | EXPORT_SYMBOL(nlmsg_notify); |