?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt...
[linux-2.6/x86.git] / net / netfilter / nfnetlink_queue.c
blobfdd2fafe0a14ed8810181aae57168f841d5b3f1e
1 /*
2 * This is a module which is used for queueing packets and communicating with
3 * userspace via nfnetlink.
4 *
5 * (C) 2005 by Harald Welte <laforge@netfilter.org>
6 * (C) 2007 by Patrick McHardy <kaber@trash.net>
7 *
8 * Based on the old ipv4-only ip_queue.c:
9 * (C) 2000-2002 James Morris <jmorris@intercode.com.au>
10 * (C) 2003-2005 Netfilter Core Team <coreteam@netfilter.org>
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License version 2 as
14 * published by the Free Software Foundation.
15 *
16 */
17 #include <linux/module.h>
18 #include <linux/skbuff.h>
19 #include <linux/init.h>
20 #include <linux/spinlock.h>
21 #include <linux/slab.h>
22 #include <linux/notifier.h>
23 #include <linux/netdevice.h>
24 #include <linux/netfilter.h>
25 #include <linux/proc_fs.h>
26 #include <linux/netfilter_ipv4.h>
27 #include <linux/netfilter_ipv6.h>
28 #include <linux/netfilter/nfnetlink.h>
29 #include <linux/netfilter/nfnetlink_queue.h>
30 #include <linux/list.h>
31 #include <net/sock.h>
32 #include <net/netfilter/nf_queue.h>
33
34 #include <asm/atomic.h>
35
36 #ifdef CONFIG_BRIDGE_NETFILTER
37 #include "../bridge/br_private.h"
38 #endif
39
40 #define NFQNL_QMAX_DEFAULT 1024
41
42 struct nfqnl_instance {
43 struct hlist_node hlist; /* global list of queues */
44 struct rcu_head rcu;
45
46 int peer_pid;
47 unsigned int queue_maxlen;
48 unsigned int copy_range;
49 unsigned int queue_dropped;
50 unsigned int queue_user_dropped;
51
52
53 u_int16_t queue_num; /* number of this queue */
54 u_int8_t copy_mode;
55 /*
56 * Following fields are dirtied for each queued packet,
57 * keep them in same cache line if possible.
58 */
59 spinlock_t lock;
60 unsigned int queue_total;
61 atomic_t id_sequence; /* 'sequence' of pkt ids */
62 struct list_head queue_list; /* packets in queue */
63 };
64
65 typedef int (*nfqnl_cmpfn)(struct nf_queue_entry *, unsigned long);
66
67 static DEFINE_SPINLOCK(instances_lock);
68
69 #define INSTANCE_BUCKETS 16
70 static struct hlist_head instance_table[INSTANCE_BUCKETS] __read_mostly;
71
72 static inline u_int8_t instance_hashfn(u_int16_t queue_num)
73 {
74 return ((queue_num >> 8) | queue_num) % INSTANCE_BUCKETS;
75 }
76
77 static struct nfqnl_instance *
78 instance_lookup(u_int16_t queue_num)
79 {
80 struct hlist_head *head;
81 struct hlist_node *pos;
82 struct nfqnl_instance *inst;
83
84 head = &instance_table[instance_hashfn(queue_num)];
85 hlist_for_each_entry_rcu(inst, pos, head, hlist) {
86 if (inst->queue_num == queue_num)
87 return inst;
88 }
89 return NULL;
90 }
91
92 static struct nfqnl_instance *
93 instance_create(u_int16_t queue_num, int pid)
94 {
95 struct nfqnl_instance *inst;
96 unsigned int h;
97 int err;
98
99 spin_lock(&instances_lock);
100 if (instance_lookup(queue_num)) {
101 err = -EEXIST;
102 goto out_unlock;
103 }
104
105 inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
106 if (!inst) {
107 err = -ENOMEM;
108 goto out_unlock;
109 }
110
111 inst->queue_num = queue_num;
112 inst->peer_pid = pid;
113 inst->queue_maxlen = NFQNL_QMAX_DEFAULT;
114 inst->copy_range = 0xfffff;
115 inst->copy_mode = NFQNL_COPY_NONE;
116 spin_lock_init(&inst->lock);
117 INIT_LIST_HEAD(&inst->queue_list);
118
119 if (!try_module_get(THIS_MODULE)) {
120 err = -EAGAIN;
121 goto out_free;
122 }
123
124 h = instance_hashfn(queue_num);
125 hlist_add_head_rcu(&inst->hlist, &instance_table[h]);
126
127 spin_unlock(&instances_lock);
128
129 return inst;
130
131 out_free:
132 kfree(inst);
133 out_unlock:
134 spin_unlock(&instances_lock);
135 return ERR_PTR(err);
136 }
137
138 static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
139 unsigned long data);
140
141 static void
142 instance_destroy_rcu(struct rcu_head *head)
143 {
144 struct nfqnl_instance *inst = container_of(head, struct nfqnl_instance,
145 rcu);
146
147 nfqnl_flush(inst, NULL, 0);
148 kfree(inst);
149 module_put(THIS_MODULE);
150 }
151
152 static void
153 __instance_destroy(struct nfqnl_instance *inst)
154 {
155 hlist_del_rcu(&inst->hlist);
156 call_rcu(&inst->rcu, instance_destroy_rcu);
157 }
158
159 static void
160 instance_destroy(struct nfqnl_instance *inst)
161 {
162 spin_lock(&instances_lock);
163 __instance_destroy(inst);
164 spin_unlock(&instances_lock);
165 }
166
167 static inline void
168 __enqueue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
169 {
170 list_add_tail(&entry->list, &queue->queue_list);
171 queue->queue_total++;
172 }
173
174 static struct nf_queue_entry *
175 find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id)
176 {
177 struct nf_queue_entry *entry = NULL, *i;
178
179 spin_lock_bh(&queue->lock);
180
181 list_for_each_entry(i, &queue->queue_list, list) {
182 if (i->id == id) {
183 entry = i;
184 break;
185 }
186 }
187
188 if (entry) {
189 list_del(&entry->list);
190 queue->queue_total--;
191 }
192
193 spin_unlock_bh(&queue->lock);
194
195 return entry;
196 }
197
198 static void
199 nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data)
200 {
201 struct nf_queue_entry *entry, *next;
202
203 spin_lock_bh(&queue->lock);
204 list_for_each_entry_safe(entry, next, &queue->queue_list, list) {
205 if (!cmpfn || cmpfn(entry, data)) {
206 list_del(&entry->list);
207 queue->queue_total--;
208 nf_reinject(entry, NF_DROP);
209 }
210 }
211 spin_unlock_bh(&queue->lock);
212 }
213
214 static struct sk_buff *
215 nfqnl_build_packet_message(struct nfqnl_instance *queue,
216 struct nf_queue_entry *entry)
217 {
218 sk_buff_data_t old_tail;
219 size_t size;
220 size_t data_len = 0;
221 struct sk_buff *skb;
222 struct nfqnl_msg_packet_hdr pmsg;
223 struct nlmsghdr *nlh;
224 struct nfgenmsg *nfmsg;
225 struct sk_buff *entskb = entry->skb;
226 struct net_device *indev;
227 struct net_device *outdev;
228
229 size = NLMSG_SPACE(sizeof(struct nfgenmsg))
230 + nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))
231 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
232 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
233 #ifdef CONFIG_BRIDGE_NETFILTER
234 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
235 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
236 #endif
237 + nla_total_size(sizeof(u_int32_t)) /* mark */
238 + nla_total_size(sizeof(struct nfqnl_msg_packet_hw))
239 + nla_total_size(sizeof(struct nfqnl_msg_packet_timestamp));
240
241 outdev = entry->outdev;
242
243 switch ((enum nfqnl_config_mode)ACCESS_ONCE(queue->copy_mode)) {
244 case NFQNL_COPY_META:
245 case NFQNL_COPY_NONE:
246 break;
247
248 case NFQNL_COPY_PACKET:
249 if (entskb->ip_summed == CHECKSUM_PARTIAL &&
250 skb_checksum_help(entskb))
251 return NULL;
252
253 data_len = ACCESS_ONCE(queue->copy_range);
254 if (data_len == 0 || data_len > entskb->len)
255 data_len = entskb->len;
256
257 size += nla_total_size(data_len);
258 break;
259 }
260
261
262 skb = alloc_skb(size, GFP_ATOMIC);
263 if (!skb)
264 goto nlmsg_failure;
265
266 old_tail = skb->tail;
267 nlh = NLMSG_PUT(skb, 0, 0,
268 NFNL_SUBSYS_QUEUE << 8 | NFQNL_MSG_PACKET,
269 sizeof(struct nfgenmsg));
270 nfmsg = NLMSG_DATA(nlh);
271 nfmsg->nfgen_family = entry->pf;
272 nfmsg->version = NFNETLINK_V0;
273 nfmsg->res_id = htons(queue->queue_num);
274
275 entry->id = atomic_inc_return(&queue->id_sequence);
276 pmsg.packet_id = htonl(entry->id);
277 pmsg.hw_protocol = entskb->protocol;
278 pmsg.hook = entry->hook;
279
280 NLA_PUT(skb, NFQA_PACKET_HDR, sizeof(pmsg), &pmsg);
281
282 indev = entry->indev;
283 if (indev) {
284 #ifndef CONFIG_BRIDGE_NETFILTER
285 NLA_PUT_BE32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex));
286 #else
287 if (entry->pf == PF_BRIDGE) {
288 /* Case 1: indev is physical input device, we need to
289 * look for bridge group (when called from
290 * netfilter_bridge) */
291 NLA_PUT_BE32(skb, NFQA_IFINDEX_PHYSINDEV,
292 htonl(indev->ifindex));
293 /* this is the bridge group "brX" */
294 /* rcu_read_lock()ed by __nf_queue */
295 NLA_PUT_BE32(skb, NFQA_IFINDEX_INDEV,
296 htonl(br_port_get_rcu(indev)->br->dev->ifindex));
297 } else {
298 /* Case 2: indev is bridge group, we need to look for
299 * physical device (when called from ipv4) */
300 NLA_PUT_BE32(skb, NFQA_IFINDEX_INDEV,
301 htonl(indev->ifindex));
302 if (entskb->nf_bridge && entskb->nf_bridge->physindev)
303 NLA_PUT_BE32(skb, NFQA_IFINDEX_PHYSINDEV,
304 htonl(entskb->nf_bridge->physindev->ifindex));
305 }
306 #endif
307 }
308
309 if (outdev) {
310 #ifndef CONFIG_BRIDGE_NETFILTER
311 NLA_PUT_BE32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex));
312 #else
313 if (entry->pf == PF_BRIDGE) {
314 /* Case 1: outdev is physical output device, we need to
315 * look for bridge group (when called from
316 * netfilter_bridge) */
317 NLA_PUT_BE32(skb, NFQA_IFINDEX_PHYSOUTDEV,
318 htonl(outdev->ifindex));
319 /* this is the bridge group "brX" */
320 /* rcu_read_lock()ed by __nf_queue */
321 NLA_PUT_BE32(skb, NFQA_IFINDEX_OUTDEV,
322 htonl(br_port_get_rcu(outdev)->br->dev->ifindex));
323 } else {
324 /* Case 2: outdev is bridge group, we need to look for
325 * physical output device (when called from ipv4) */
326 NLA_PUT_BE32(skb, NFQA_IFINDEX_OUTDEV,
327 htonl(outdev->ifindex));
328 if (entskb->nf_bridge && entskb->nf_bridge->physoutdev)
329 NLA_PUT_BE32(skb, NFQA_IFINDEX_PHYSOUTDEV,
330 htonl(entskb->nf_bridge->physoutdev->ifindex));
331 }
332 #endif
333 }
334
335 if (entskb->mark)
336 NLA_PUT_BE32(skb, NFQA_MARK, htonl(entskb->mark));
337
338 if (indev && entskb->dev &&
339 entskb->mac_header != entskb->network_header) {
340 struct nfqnl_msg_packet_hw phw;
341 int len = dev_parse_header(entskb, phw.hw_addr);
342 if (len) {
343 phw.hw_addrlen = htons(len);
344 NLA_PUT(skb, NFQA_HWADDR, sizeof(phw), &phw);
345 }
346 }
347
348 if (entskb->tstamp.tv64) {
349 struct nfqnl_msg_packet_timestamp ts;
350 struct timeval tv = ktime_to_timeval(entskb->tstamp);
351 ts.sec = cpu_to_be64(tv.tv_sec);
352 ts.usec = cpu_to_be64(tv.tv_usec);
353
354 NLA_PUT(skb, NFQA_TIMESTAMP, sizeof(ts), &ts);
355 }
356
357 if (data_len) {
358 struct nlattr *nla;
359 int sz = nla_attr_size(data_len);
360
361 if (skb_tailroom(skb) < nla_total_size(data_len)) {
362 printk(KERN_WARNING "nf_queue: no tailroom!\n");
363 goto nlmsg_failure;
364 }
365
366 nla = (struct nlattr *)skb_put(skb, nla_total_size(data_len));
367 nla->nla_type = NFQA_PAYLOAD;
368 nla->nla_len = sz;
369
370 if (skb_copy_bits(entskb, 0, nla_data(nla), data_len))
371 BUG();
372 }
373
374 nlh->nlmsg_len = skb->tail - old_tail;
375 return skb;
376
377 nlmsg_failure:
378 nla_put_failure:
379 if (skb)
380 kfree_skb(skb);
381 if (net_ratelimit())
382 printk(KERN_ERR "nf_queue: error creating packet message\n");
383 return NULL;
384 }
385
386 static int
387 nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
388 {
389 struct sk_buff *nskb;
390 struct nfqnl_instance *queue;
391 int err = -ENOBUFS;
392
393 /* rcu_read_lock()ed by nf_hook_slow() */
394 queue = instance_lookup(queuenum);
395 if (!queue) {
396 err = -ESRCH;
397 goto err_out;
398 }
399
400 if (queue->copy_mode == NFQNL_COPY_NONE) {
401 err = -EINVAL;
402 goto err_out;
403 }
404
405 nskb = nfqnl_build_packet_message(queue, entry);
406 if (nskb == NULL) {
407 err = -ENOMEM;
408 goto err_out;
409 }
410 spin_lock_bh(&queue->lock);
411
412 if (!queue->peer_pid) {
413 err = -EINVAL;
414 goto err_out_free_nskb;
415 }
416 if (queue->queue_total >= queue->queue_maxlen) {
417 queue->queue_dropped++;
418 if (net_ratelimit())
419 printk(KERN_WARNING "nf_queue: full at %d entries, "
420 "dropping packets(s).\n",
421 queue->queue_total);
422 goto err_out_free_nskb;
423 }
424
425 /* nfnetlink_unicast will either free the nskb or add it to a socket */
426 err = nfnetlink_unicast(nskb, &init_net, queue->peer_pid, MSG_DONTWAIT);
427 if (err < 0) {
428 queue->queue_user_dropped++;
429 goto err_out_unlock;
430 }
431
432 __enqueue_entry(queue, entry);
433
434 spin_unlock_bh(&queue->lock);
435 return 0;
436
437 err_out_free_nskb:
438 kfree_skb(nskb);
439 err_out_unlock:
440 spin_unlock_bh(&queue->lock);
441 err_out:
442 return err;
443 }
444
445 static int
446 nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e)
447 {
448 struct sk_buff *nskb;
449 int diff;
450
451 diff = data_len - e->skb->len;
452 if (diff < 0) {
453 if (pskb_trim(e->skb, data_len))
454 return -ENOMEM;
455 } else if (diff > 0) {
456 if (data_len > 0xFFFF)
457 return -EINVAL;
458 if (diff > skb_tailroom(e->skb)) {
459 nskb = skb_copy_expand(e->skb, skb_headroom(e->skb),
460 diff, GFP_ATOMIC);
461 if (!nskb) {
462 printk(KERN_WARNING "nf_queue: OOM "
463 "in mangle, dropping packet\n");
464 return -ENOMEM;
465 }
466 kfree_skb(e->skb);
467 e->skb = nskb;
468 }
469 skb_put(e->skb, diff);
470 }
471 if (!skb_make_writable(e->skb, data_len))
472 return -ENOMEM;
473 skb_copy_to_linear_data(e->skb, data, data_len);
474 e->skb->ip_summed = CHECKSUM_NONE;
475 return 0;
476 }
477
478 static int
479 nfqnl_set_mode(struct nfqnl_instance *queue,
480 unsigned char mode, unsigned int range)
481 {
482 int status = 0;
483
484 spin_lock_bh(&queue->lock);
485 switch (mode) {
486 case NFQNL_COPY_NONE:
487 case NFQNL_COPY_META:
488 queue->copy_mode = mode;
489 queue->copy_range = 0;
490 break;
491
492 case NFQNL_COPY_PACKET:
493 queue->copy_mode = mode;
494 /* we're using struct nlattr which has 16bit nla_len */
495 if (range > 0xffff)
496 queue->copy_range = 0xffff;
497 else
498 queue->copy_range = range;
499 break;
500
501 default:
502 status = -EINVAL;
503
504 }
505 spin_unlock_bh(&queue->lock);
506
507 return status;
508 }
509
510 static int
511 dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex)
512 {
513 if (entry->indev)
514 if (entry->indev->ifindex == ifindex)
515 return 1;
516 if (entry->outdev)
517 if (entry->outdev->ifindex == ifindex)
518 return 1;
519 #ifdef CONFIG_BRIDGE_NETFILTER
520 if (entry->skb->nf_bridge) {
521 if (entry->skb->nf_bridge->physindev &&
522 entry->skb->nf_bridge->physindev->ifindex == ifindex)
523 return 1;
524 if (entry->skb->nf_bridge->physoutdev &&
525 entry->skb->nf_bridge->physoutdev->ifindex == ifindex)
526 return 1;
527 }
528 #endif
529 return 0;
530 }
531
532 /* drop all packets with either indev or outdev == ifindex from all queue
533 * instances */
534 static void
535 nfqnl_dev_drop(int ifindex)
536 {
537 int i;
538
539 rcu_read_lock();
540
541 for (i = 0; i < INSTANCE_BUCKETS; i++) {
542 struct hlist_node *tmp;
543 struct nfqnl_instance *inst;
544 struct hlist_head *head = &instance_table[i];
545
546 hlist_for_each_entry_rcu(inst, tmp, head, hlist)
547 nfqnl_flush(inst, dev_cmp, ifindex);
548 }
549
550 rcu_read_unlock();
551 }
552
553 #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
554
555 static int
556 nfqnl_rcv_dev_event(struct notifier_block *this,
557 unsigned long event, void *ptr)
558 {
559 struct net_device *dev = ptr;
560
561 if (!net_eq(dev_net(dev), &init_net))
562 return NOTIFY_DONE;
563
564 /* Drop any packets associated with the downed device */
565 if (event == NETDEV_DOWN)
566 nfqnl_dev_drop(dev->ifindex);
567 return NOTIFY_DONE;
568 }
569
570 static struct notifier_block nfqnl_dev_notifier = {
571 .notifier_call = nfqnl_rcv_dev_event,
572 };
573
574 static int
575 nfqnl_rcv_nl_event(struct notifier_block *this,
576 unsigned long event, void *ptr)
577 {
578 struct netlink_notify *n = ptr;
579
580 if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
581 int i;
582
583 /* destroy all instances for this pid */
584 spin_lock(&instances_lock);
585 for (i = 0; i < INSTANCE_BUCKETS; i++) {
586 struct hlist_node *tmp, *t2;
587 struct nfqnl_instance *inst;
588 struct hlist_head *head = &instance_table[i];
589
590 hlist_for_each_entry_safe(inst, tmp, t2, head, hlist) {
591 if ((n->net == &init_net) &&
592 (n->pid == inst->peer_pid))
593 __instance_destroy(inst);
594 }
595 }
596 spin_unlock(&instances_lock);
597 }
598 return NOTIFY_DONE;
599 }
600
601 static struct notifier_block nfqnl_rtnl_notifier = {
602 .notifier_call = nfqnl_rcv_nl_event,
603 };
604
605 static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = {
606 [NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
607 [NFQA_MARK] = { .type = NLA_U32 },
608 [NFQA_PAYLOAD] = { .type = NLA_UNSPEC },
609 };
610
611 static int
612 nfqnl_recv_verdict(struct sock *ctnl, struct sk_buff *skb,
613 const struct nlmsghdr *nlh,
614 const struct nlattr * const nfqa[])
615 {
616 struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
617 u_int16_t queue_num = ntohs(nfmsg->res_id);
618
619 struct nfqnl_msg_verdict_hdr *vhdr;
620 struct nfqnl_instance *queue;
621 unsigned int verdict;
622 struct nf_queue_entry *entry;
623 int err;
624
625 rcu_read_lock();
626 queue = instance_lookup(queue_num);
627 if (!queue) {
628 err = -ENODEV;
629 goto err_out_unlock;
630 }
631
632 if (queue->peer_pid != NETLINK_CB(skb).pid) {
633 err = -EPERM;
634 goto err_out_unlock;
635 }
636
637 if (!nfqa[NFQA_VERDICT_HDR]) {
638 err = -EINVAL;
639 goto err_out_unlock;
640 }
641
642 vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]);
643 verdict = ntohl(vhdr->verdict);
644
645 if ((verdict & NF_VERDICT_MASK) > NF_MAX_VERDICT) {
646 err = -EINVAL;
647 goto err_out_unlock;
648 }
649
650 entry = find_dequeue_entry(queue, ntohl(vhdr->id));
651 if (entry == NULL) {
652 err = -ENOENT;
653 goto err_out_unlock;
654 }
655 rcu_read_unlock();
656
657 if (nfqa[NFQA_PAYLOAD]) {
658 if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),
659 nla_len(nfqa[NFQA_PAYLOAD]), entry) < 0)
660 verdict = NF_DROP;
661 }
662
663 if (nfqa[NFQA_MARK])
664 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
665
666 nf_reinject(entry, verdict);
667 return 0;
668
669 err_out_unlock:
670 rcu_read_unlock();
671 return err;
672 }
673
674 static int
675 nfqnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb,
676 const struct nlmsghdr *nlh,
677 const struct nlattr * const nfqa[])
678 {
679 return -ENOTSUPP;
680 }
681
682 static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = {
683 [NFQA_CFG_CMD] = { .len = sizeof(struct nfqnl_msg_config_cmd) },
684 [NFQA_CFG_PARAMS] = { .len = sizeof(struct nfqnl_msg_config_params) },
685 };
686
687 static const struct nf_queue_handler nfqh = {
688 .name = "nf_queue",
689 .outfn = &nfqnl_enqueue_packet,
690 };
691
692 static int
693 nfqnl_recv_config(struct sock *ctnl, struct sk_buff *skb,
694 const struct nlmsghdr *nlh,
695 const struct nlattr * const nfqa[])
696 {
697 struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
698 u_int16_t queue_num = ntohs(nfmsg->res_id);
699 struct nfqnl_instance *queue;
700 struct nfqnl_msg_config_cmd *cmd = NULL;
701 int ret = 0;
702
703 if (nfqa[NFQA_CFG_CMD]) {
704 cmd = nla_data(nfqa[NFQA_CFG_CMD]);
705
706 /* Commands without queue context - might sleep */
707 switch (cmd->command) {
708 case NFQNL_CFG_CMD_PF_BIND:
709 return nf_register_queue_handler(ntohs(cmd->pf),
710 &nfqh);
711 case NFQNL_CFG_CMD_PF_UNBIND:
712 return nf_unregister_queue_handler(ntohs(cmd->pf),
713 &nfqh);
714 }
715 }
716
717 rcu_read_lock();
718 queue = instance_lookup(queue_num);
719 if (queue && queue->peer_pid != NETLINK_CB(skb).pid) {
720 ret = -EPERM;
721 goto err_out_unlock;
722 }
723
724 if (cmd != NULL) {
725 switch (cmd->command) {
726 case NFQNL_CFG_CMD_BIND:
727 if (queue) {
728 ret = -EBUSY;
729 goto err_out_unlock;
730 }
731 queue = instance_create(queue_num, NETLINK_CB(skb).pid);
732 if (IS_ERR(queue)) {
733 ret = PTR_ERR(queue);
734 goto err_out_unlock;
735 }
736 break;
737 case NFQNL_CFG_CMD_UNBIND:
738 if (!queue) {
739 ret = -ENODEV;
740 goto err_out_unlock;
741 }
742 instance_destroy(queue);
743 break;
744 case NFQNL_CFG_CMD_PF_BIND:
745 case NFQNL_CFG_CMD_PF_UNBIND:
746 break;
747 default:
748 ret = -ENOTSUPP;
749 break;
750 }
751 }
752
753 if (nfqa[NFQA_CFG_PARAMS]) {
754 struct nfqnl_msg_config_params *params;
755
756 if (!queue) {
757 ret = -ENODEV;
758 goto err_out_unlock;
759 }
760 params = nla_data(nfqa[NFQA_CFG_PARAMS]);
761 nfqnl_set_mode(queue, params->copy_mode,
762 ntohl(params->copy_range));
763 }
764
765 if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) {
766 __be32 *queue_maxlen;
767
768 if (!queue) {
769 ret = -ENODEV;
770 goto err_out_unlock;
771 }
772 queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]);
773 spin_lock_bh(&queue->lock);
774 queue->queue_maxlen = ntohl(*queue_maxlen);
775 spin_unlock_bh(&queue->lock);
776 }
777
778 err_out_unlock:
779 rcu_read_unlock();
780 return ret;
781 }
782
783 static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
784 [NFQNL_MSG_PACKET] = { .call = nfqnl_recv_unsupp,
785 .attr_count = NFQA_MAX, },
786 [NFQNL_MSG_VERDICT] = { .call = nfqnl_recv_verdict,
787 .attr_count = NFQA_MAX,
788 .policy = nfqa_verdict_policy },
789 [NFQNL_MSG_CONFIG] = { .call = nfqnl_recv_config,
790 .attr_count = NFQA_CFG_MAX,
791 .policy = nfqa_cfg_policy },
792 };
793
794 static const struct nfnetlink_subsystem nfqnl_subsys = {
795 .name = "nf_queue",
796 .subsys_id = NFNL_SUBSYS_QUEUE,
797 .cb_count = NFQNL_MSG_MAX,
798 .cb = nfqnl_cb,
799 };
800
801 #ifdef CONFIG_PROC_FS
802 struct iter_state {
803 unsigned int bucket;
804 };
805
806 static struct hlist_node *get_first(struct seq_file *seq)
807 {
808 struct iter_state *st = seq->private;
809
810 if (!st)
811 return NULL;
812
813 for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
814 if (!hlist_empty(&instance_table[st->bucket]))
815 return instance_table[st->bucket].first;
816 }
817 return NULL;
818 }
819
820 static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h)
821 {
822 struct iter_state *st = seq->private;
823
824 h = h->next;
825 while (!h) {
826 if (++st->bucket >= INSTANCE_BUCKETS)
827 return NULL;
828
829 h = instance_table[st->bucket].first;
830 }
831 return h;
832 }
833
834 static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos)
835 {
836 struct hlist_node *head;
837 head = get_first(seq);
838
839 if (head)
840 while (pos && (head = get_next(seq, head)))
841 pos--;
842 return pos ? NULL : head;
843 }
844
845 static void *seq_start(struct seq_file *seq, loff_t *pos)
846 __acquires(instances_lock)
847 {
848 spin_lock(&instances_lock);
849 return get_idx(seq, *pos);
850 }
851
852 static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
853 {
854 (*pos)++;
855 return get_next(s, v);
856 }
857
858 static void seq_stop(struct seq_file *s, void *v)
859 __releases(instances_lock)
860 {
861 spin_unlock(&instances_lock);
862 }
863
864 static int seq_show(struct seq_file *s, void *v)
865 {
866 const struct nfqnl_instance *inst = v;
867
868 return seq_printf(s, "%5d %6d %5d %1d %5d %5d %5d %8d %2d\n",
869 inst->queue_num,
870 inst->peer_pid, inst->queue_total,
871 inst->copy_mode, inst->copy_range,
872 inst->queue_dropped, inst->queue_user_dropped,
873 atomic_read(&inst->id_sequence), 1);
874 }
875
876 static const struct seq_operations nfqnl_seq_ops = {
877 .start = seq_start,
878 .next = seq_next,
879 .stop = seq_stop,
880 .show = seq_show,
881 };
882
883 static int nfqnl_open(struct inode *inode, struct file *file)
884 {
885 return seq_open_private(file, &nfqnl_seq_ops,
886 sizeof(struct iter_state));
887 }
888
889 static const struct file_operations nfqnl_file_ops = {
890 .owner = THIS_MODULE,
891 .open = nfqnl_open,
892 .read = seq_read,
893 .llseek = seq_lseek,
894 .release = seq_release_private,
895 };
896
897 #endif /* PROC_FS */
898
899 static int __init nfnetlink_queue_init(void)
900 {
901 int i, status = -ENOMEM;
902
903 for (i = 0; i < INSTANCE_BUCKETS; i++)
904 INIT_HLIST_HEAD(&instance_table[i]);
905
906 netlink_register_notifier(&nfqnl_rtnl_notifier);
907 status = nfnetlink_subsys_register(&nfqnl_subsys);
908 if (status < 0) {
909 printk(KERN_ERR "nf_queue: failed to create netlink socket\n");
910 goto cleanup_netlink_notifier;
911 }
912
913 #ifdef CONFIG_PROC_FS
914 if (!proc_create("nfnetlink_queue", 0440,
915 proc_net_netfilter, &nfqnl_file_ops))
916 goto cleanup_subsys;
917 #endif
918
919 register_netdevice_notifier(&nfqnl_dev_notifier);
920 return status;
921
922 #ifdef CONFIG_PROC_FS
923 cleanup_subsys:
924 nfnetlink_subsys_unregister(&nfqnl_subsys);
925 #endif
926 cleanup_netlink_notifier:
927 netlink_unregister_notifier(&nfqnl_rtnl_notifier);
928 return status;
929 }
930
931 static void __exit nfnetlink_queue_fini(void)
932 {
933 nf_unregister_queue_handlers(&nfqh);
934 unregister_netdevice_notifier(&nfqnl_dev_notifier);
935 #ifdef CONFIG_PROC_FS
936 remove_proc_entry("nfnetlink_queue", proc_net_netfilter);
937 #endif
938 nfnetlink_subsys_unregister(&nfqnl_subsys);
939 netlink_unregister_notifier(&nfqnl_rtnl_notifier);
940
941 rcu_barrier(); /* Wait for completion of call_rcu()'s */
942 }
943
944 MODULE_DESCRIPTION("netfilter packet queue handler");
945 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
946 MODULE_LICENSE("GPL");
947 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE);
948
949 module_init(nfnetlink_queue_init);
950 module_exit(nfnetlink_queue_fini);
x86 "subsystem" repository