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Merge branch 'media_fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab...
[cris-mirror.git] / net / netfilter / nfnetlink_queue.c
blob68e67d19724d83f844c25a5aa0f603156421f57e
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 struct nfqnl_msg_packet_hw phw;
340 int len = dev_parse_header(entskb, phw.hw_addr);
341 if (len) {
342 phw.hw_addrlen = htons(len);
343 NLA_PUT(skb, NFQA_HWADDR, sizeof(phw), &phw);
344 }
345 }
346
347 if (entskb->tstamp.tv64) {
348 struct nfqnl_msg_packet_timestamp ts;
349 struct timeval tv = ktime_to_timeval(entskb->tstamp);
350 ts.sec = cpu_to_be64(tv.tv_sec);
351 ts.usec = cpu_to_be64(tv.tv_usec);
352
353 NLA_PUT(skb, NFQA_TIMESTAMP, sizeof(ts), &ts);
354 }
355
356 if (data_len) {
357 struct nlattr *nla;
358 int sz = nla_attr_size(data_len);
359
360 if (skb_tailroom(skb) < nla_total_size(data_len)) {
361 printk(KERN_WARNING "nf_queue: no tailroom!\n");
362 goto nlmsg_failure;
363 }
364
365 nla = (struct nlattr *)skb_put(skb, nla_total_size(data_len));
366 nla->nla_type = NFQA_PAYLOAD;
367 nla->nla_len = sz;
368
369 if (skb_copy_bits(entskb, 0, nla_data(nla), data_len))
370 BUG();
371 }
372
373 nlh->nlmsg_len = skb->tail - old_tail;
374 return skb;
375
376 nlmsg_failure:
377 nla_put_failure:
378 if (skb)
379 kfree_skb(skb);
380 if (net_ratelimit())
381 printk(KERN_ERR "nf_queue: error creating packet message\n");
382 return NULL;
383 }
384
385 static int
386 nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
387 {
388 struct sk_buff *nskb;
389 struct nfqnl_instance *queue;
390 int err;
391
392 /* rcu_read_lock()ed by nf_hook_slow() */
393 queue = instance_lookup(queuenum);
394 if (!queue)
395 goto err_out;
396
397 if (queue->copy_mode == NFQNL_COPY_NONE)
398 goto err_out;
399
400 nskb = nfqnl_build_packet_message(queue, entry);
401 if (nskb == NULL)
402 goto err_out;
403
404 spin_lock_bh(&queue->lock);
405
406 if (!queue->peer_pid)
407 goto err_out_free_nskb;
408
409 if (queue->queue_total >= queue->queue_maxlen) {
410 queue->queue_dropped++;
411 if (net_ratelimit())
412 printk(KERN_WARNING "nf_queue: full at %d entries, "
413 "dropping packets(s).\n",
414 queue->queue_total);
415 goto err_out_free_nskb;
416 }
417
418 /* nfnetlink_unicast will either free the nskb or add it to a socket */
419 err = nfnetlink_unicast(nskb, &init_net, queue->peer_pid, MSG_DONTWAIT);
420 if (err < 0) {
421 queue->queue_user_dropped++;
422 goto err_out_unlock;
423 }
424
425 __enqueue_entry(queue, entry);
426
427 spin_unlock_bh(&queue->lock);
428 return 0;
429
430 err_out_free_nskb:
431 kfree_skb(nskb);
432 err_out_unlock:
433 spin_unlock_bh(&queue->lock);
434 err_out:
435 return -1;
436 }
437
438 static int
439 nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e)
440 {
441 struct sk_buff *nskb;
442 int diff;
443
444 diff = data_len - e->skb->len;
445 if (diff < 0) {
446 if (pskb_trim(e->skb, data_len))
447 return -ENOMEM;
448 } else if (diff > 0) {
449 if (data_len > 0xFFFF)
450 return -EINVAL;
451 if (diff > skb_tailroom(e->skb)) {
452 nskb = skb_copy_expand(e->skb, skb_headroom(e->skb),
453 diff, GFP_ATOMIC);
454 if (!nskb) {
455 printk(KERN_WARNING "nf_queue: OOM "
456 "in mangle, dropping packet\n");
457 return -ENOMEM;
458 }
459 kfree_skb(e->skb);
460 e->skb = nskb;
461 }
462 skb_put(e->skb, diff);
463 }
464 if (!skb_make_writable(e->skb, data_len))
465 return -ENOMEM;
466 skb_copy_to_linear_data(e->skb, data, data_len);
467 e->skb->ip_summed = CHECKSUM_NONE;
468 return 0;
469 }
470
471 static int
472 nfqnl_set_mode(struct nfqnl_instance *queue,
473 unsigned char mode, unsigned int range)
474 {
475 int status = 0;
476
477 spin_lock_bh(&queue->lock);
478 switch (mode) {
479 case NFQNL_COPY_NONE:
480 case NFQNL_COPY_META:
481 queue->copy_mode = mode;
482 queue->copy_range = 0;
483 break;
484
485 case NFQNL_COPY_PACKET:
486 queue->copy_mode = mode;
487 /* we're using struct nlattr which has 16bit nla_len */
488 if (range > 0xffff)
489 queue->copy_range = 0xffff;
490 else
491 queue->copy_range = range;
492 break;
493
494 default:
495 status = -EINVAL;
496
497 }
498 spin_unlock_bh(&queue->lock);
499
500 return status;
501 }
502
503 static int
504 dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex)
505 {
506 if (entry->indev)
507 if (entry->indev->ifindex == ifindex)
508 return 1;
509 if (entry->outdev)
510 if (entry->outdev->ifindex == ifindex)
511 return 1;
512 #ifdef CONFIG_BRIDGE_NETFILTER
513 if (entry->skb->nf_bridge) {
514 if (entry->skb->nf_bridge->physindev &&
515 entry->skb->nf_bridge->physindev->ifindex == ifindex)
516 return 1;
517 if (entry->skb->nf_bridge->physoutdev &&
518 entry->skb->nf_bridge->physoutdev->ifindex == ifindex)
519 return 1;
520 }
521 #endif
522 return 0;
523 }
524
525 /* drop all packets with either indev or outdev == ifindex from all queue
526 * instances */
527 static void
528 nfqnl_dev_drop(int ifindex)
529 {
530 int i;
531
532 rcu_read_lock();
533
534 for (i = 0; i < INSTANCE_BUCKETS; i++) {
535 struct hlist_node *tmp;
536 struct nfqnl_instance *inst;
537 struct hlist_head *head = &instance_table[i];
538
539 hlist_for_each_entry_rcu(inst, tmp, head, hlist)
540 nfqnl_flush(inst, dev_cmp, ifindex);
541 }
542
543 rcu_read_unlock();
544 }
545
546 #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
547
548 static int
549 nfqnl_rcv_dev_event(struct notifier_block *this,
550 unsigned long event, void *ptr)
551 {
552 struct net_device *dev = ptr;
553
554 if (!net_eq(dev_net(dev), &init_net))
555 return NOTIFY_DONE;
556
557 /* Drop any packets associated with the downed device */
558 if (event == NETDEV_DOWN)
559 nfqnl_dev_drop(dev->ifindex);
560 return NOTIFY_DONE;
561 }
562
563 static struct notifier_block nfqnl_dev_notifier = {
564 .notifier_call = nfqnl_rcv_dev_event,
565 };
566
567 static int
568 nfqnl_rcv_nl_event(struct notifier_block *this,
569 unsigned long event, void *ptr)
570 {
571 struct netlink_notify *n = ptr;
572
573 if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
574 int i;
575
576 /* destroy all instances for this pid */
577 spin_lock(&instances_lock);
578 for (i = 0; i < INSTANCE_BUCKETS; i++) {
579 struct hlist_node *tmp, *t2;
580 struct nfqnl_instance *inst;
581 struct hlist_head *head = &instance_table[i];
582
583 hlist_for_each_entry_safe(inst, tmp, t2, head, hlist) {
584 if ((n->net == &init_net) &&
585 (n->pid == inst->peer_pid))
586 __instance_destroy(inst);
587 }
588 }
589 spin_unlock(&instances_lock);
590 }
591 return NOTIFY_DONE;
592 }
593
594 static struct notifier_block nfqnl_rtnl_notifier = {
595 .notifier_call = nfqnl_rcv_nl_event,
596 };
597
598 static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = {
599 [NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
600 [NFQA_MARK] = { .type = NLA_U32 },
601 [NFQA_PAYLOAD] = { .type = NLA_UNSPEC },
602 };
603
604 static int
605 nfqnl_recv_verdict(struct sock *ctnl, struct sk_buff *skb,
606 const struct nlmsghdr *nlh,
607 const struct nlattr * const nfqa[])
608 {
609 struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
610 u_int16_t queue_num = ntohs(nfmsg->res_id);
611
612 struct nfqnl_msg_verdict_hdr *vhdr;
613 struct nfqnl_instance *queue;
614 unsigned int verdict;
615 struct nf_queue_entry *entry;
616 int err;
617
618 rcu_read_lock();
619 queue = instance_lookup(queue_num);
620 if (!queue) {
621 err = -ENODEV;
622 goto err_out_unlock;
623 }
624
625 if (queue->peer_pid != NETLINK_CB(skb).pid) {
626 err = -EPERM;
627 goto err_out_unlock;
628 }
629
630 if (!nfqa[NFQA_VERDICT_HDR]) {
631 err = -EINVAL;
632 goto err_out_unlock;
633 }
634
635 vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]);
636 verdict = ntohl(vhdr->verdict);
637
638 if ((verdict & NF_VERDICT_MASK) > NF_MAX_VERDICT) {
639 err = -EINVAL;
640 goto err_out_unlock;
641 }
642
643 entry = find_dequeue_entry(queue, ntohl(vhdr->id));
644 if (entry == NULL) {
645 err = -ENOENT;
646 goto err_out_unlock;
647 }
648 rcu_read_unlock();
649
650 if (nfqa[NFQA_PAYLOAD]) {
651 if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),
652 nla_len(nfqa[NFQA_PAYLOAD]), entry) < 0)
653 verdict = NF_DROP;
654 }
655
656 if (nfqa[NFQA_MARK])
657 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
658
659 nf_reinject(entry, verdict);
660 return 0;
661
662 err_out_unlock:
663 rcu_read_unlock();
664 return err;
665 }
666
667 static int
668 nfqnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb,
669 const struct nlmsghdr *nlh,
670 const struct nlattr * const nfqa[])
671 {
672 return -ENOTSUPP;
673 }
674
675 static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = {
676 [NFQA_CFG_CMD] = { .len = sizeof(struct nfqnl_msg_config_cmd) },
677 [NFQA_CFG_PARAMS] = { .len = sizeof(struct nfqnl_msg_config_params) },
678 };
679
680 static const struct nf_queue_handler nfqh = {
681 .name = "nf_queue",
682 .outfn = &nfqnl_enqueue_packet,
683 };
684
685 static int
686 nfqnl_recv_config(struct sock *ctnl, struct sk_buff *skb,
687 const struct nlmsghdr *nlh,
688 const struct nlattr * const nfqa[])
689 {
690 struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
691 u_int16_t queue_num = ntohs(nfmsg->res_id);
692 struct nfqnl_instance *queue;
693 struct nfqnl_msg_config_cmd *cmd = NULL;
694 int ret = 0;
695
696 if (nfqa[NFQA_CFG_CMD]) {
697 cmd = nla_data(nfqa[NFQA_CFG_CMD]);
698
699 /* Commands without queue context - might sleep */
700 switch (cmd->command) {
701 case NFQNL_CFG_CMD_PF_BIND:
702 return nf_register_queue_handler(ntohs(cmd->pf),
703 &nfqh);
704 case NFQNL_CFG_CMD_PF_UNBIND:
705 return nf_unregister_queue_handler(ntohs(cmd->pf),
706 &nfqh);
707 }
708 }
709
710 rcu_read_lock();
711 queue = instance_lookup(queue_num);
712 if (queue && queue->peer_pid != NETLINK_CB(skb).pid) {
713 ret = -EPERM;
714 goto err_out_unlock;
715 }
716
717 if (cmd != NULL) {
718 switch (cmd->command) {
719 case NFQNL_CFG_CMD_BIND:
720 if (queue) {
721 ret = -EBUSY;
722 goto err_out_unlock;
723 }
724 queue = instance_create(queue_num, NETLINK_CB(skb).pid);
725 if (IS_ERR(queue)) {
726 ret = PTR_ERR(queue);
727 goto err_out_unlock;
728 }
729 break;
730 case NFQNL_CFG_CMD_UNBIND:
731 if (!queue) {
732 ret = -ENODEV;
733 goto err_out_unlock;
734 }
735 instance_destroy(queue);
736 break;
737 case NFQNL_CFG_CMD_PF_BIND:
738 case NFQNL_CFG_CMD_PF_UNBIND:
739 break;
740 default:
741 ret = -ENOTSUPP;
742 break;
743 }
744 }
745
746 if (nfqa[NFQA_CFG_PARAMS]) {
747 struct nfqnl_msg_config_params *params;
748
749 if (!queue) {
750 ret = -ENODEV;
751 goto err_out_unlock;
752 }
753 params = nla_data(nfqa[NFQA_CFG_PARAMS]);
754 nfqnl_set_mode(queue, params->copy_mode,
755 ntohl(params->copy_range));
756 }
757
758 if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) {
759 __be32 *queue_maxlen;
760
761 if (!queue) {
762 ret = -ENODEV;
763 goto err_out_unlock;
764 }
765 queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]);
766 spin_lock_bh(&queue->lock);
767 queue->queue_maxlen = ntohl(*queue_maxlen);
768 spin_unlock_bh(&queue->lock);
769 }
770
771 err_out_unlock:
772 rcu_read_unlock();
773 return ret;
774 }
775
776 static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
777 [NFQNL_MSG_PACKET] = { .call = nfqnl_recv_unsupp,
778 .attr_count = NFQA_MAX, },
779 [NFQNL_MSG_VERDICT] = { .call = nfqnl_recv_verdict,
780 .attr_count = NFQA_MAX,
781 .policy = nfqa_verdict_policy },
782 [NFQNL_MSG_CONFIG] = { .call = nfqnl_recv_config,
783 .attr_count = NFQA_CFG_MAX,
784 .policy = nfqa_cfg_policy },
785 };
786
787 static const struct nfnetlink_subsystem nfqnl_subsys = {
788 .name = "nf_queue",
789 .subsys_id = NFNL_SUBSYS_QUEUE,
790 .cb_count = NFQNL_MSG_MAX,
791 .cb = nfqnl_cb,
792 };
793
794 #ifdef CONFIG_PROC_FS
795 struct iter_state {
796 unsigned int bucket;
797 };
798
799 static struct hlist_node *get_first(struct seq_file *seq)
800 {
801 struct iter_state *st = seq->private;
802
803 if (!st)
804 return NULL;
805
806 for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
807 if (!hlist_empty(&instance_table[st->bucket]))
808 return instance_table[st->bucket].first;
809 }
810 return NULL;
811 }
812
813 static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h)
814 {
815 struct iter_state *st = seq->private;
816
817 h = h->next;
818 while (!h) {
819 if (++st->bucket >= INSTANCE_BUCKETS)
820 return NULL;
821
822 h = instance_table[st->bucket].first;
823 }
824 return h;
825 }
826
827 static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos)
828 {
829 struct hlist_node *head;
830 head = get_first(seq);
831
832 if (head)
833 while (pos && (head = get_next(seq, head)))
834 pos--;
835 return pos ? NULL : head;
836 }
837
838 static void *seq_start(struct seq_file *seq, loff_t *pos)
839 __acquires(instances_lock)
840 {
841 spin_lock(&instances_lock);
842 return get_idx(seq, *pos);
843 }
844
845 static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
846 {
847 (*pos)++;
848 return get_next(s, v);
849 }
850
851 static void seq_stop(struct seq_file *s, void *v)
852 __releases(instances_lock)
853 {
854 spin_unlock(&instances_lock);
855 }
856
857 static int seq_show(struct seq_file *s, void *v)
858 {
859 const struct nfqnl_instance *inst = v;
860
861 return seq_printf(s, "%5d %6d %5d %1d %5d %5d %5d %8d %2d\n",
862 inst->queue_num,
863 inst->peer_pid, inst->queue_total,
864 inst->copy_mode, inst->copy_range,
865 inst->queue_dropped, inst->queue_user_dropped,
866 atomic_read(&inst->id_sequence), 1);
867 }
868
869 static const struct seq_operations nfqnl_seq_ops = {
870 .start = seq_start,
871 .next = seq_next,
872 .stop = seq_stop,
873 .show = seq_show,
874 };
875
876 static int nfqnl_open(struct inode *inode, struct file *file)
877 {
878 return seq_open_private(file, &nfqnl_seq_ops,
879 sizeof(struct iter_state));
880 }
881
882 static const struct file_operations nfqnl_file_ops = {
883 .owner = THIS_MODULE,
884 .open = nfqnl_open,
885 .read = seq_read,
886 .llseek = seq_lseek,
887 .release = seq_release_private,
888 };
889
890 #endif /* PROC_FS */
891
892 static int __init nfnetlink_queue_init(void)
893 {
894 int i, status = -ENOMEM;
895
896 for (i = 0; i < INSTANCE_BUCKETS; i++)
897 INIT_HLIST_HEAD(&instance_table[i]);
898
899 netlink_register_notifier(&nfqnl_rtnl_notifier);
900 status = nfnetlink_subsys_register(&nfqnl_subsys);
901 if (status < 0) {
902 printk(KERN_ERR "nf_queue: failed to create netlink socket\n");
903 goto cleanup_netlink_notifier;
904 }
905
906 #ifdef CONFIG_PROC_FS
907 if (!proc_create("nfnetlink_queue", 0440,
908 proc_net_netfilter, &nfqnl_file_ops))
909 goto cleanup_subsys;
910 #endif
911
912 register_netdevice_notifier(&nfqnl_dev_notifier);
913 return status;
914
915 #ifdef CONFIG_PROC_FS
916 cleanup_subsys:
917 nfnetlink_subsys_unregister(&nfqnl_subsys);
918 #endif
919 cleanup_netlink_notifier:
920 netlink_unregister_notifier(&nfqnl_rtnl_notifier);
921 return status;
922 }
923
924 static void __exit nfnetlink_queue_fini(void)
925 {
926 nf_unregister_queue_handlers(&nfqh);
927 unregister_netdevice_notifier(&nfqnl_dev_notifier);
928 #ifdef CONFIG_PROC_FS
929 remove_proc_entry("nfnetlink_queue", proc_net_netfilter);
930 #endif
931 nfnetlink_subsys_unregister(&nfqnl_subsys);
932 netlink_unregister_notifier(&nfqnl_rtnl_notifier);
933
934 rcu_barrier(); /* Wait for completion of call_rcu()'s */
935 }
936
937 MODULE_DESCRIPTION("netfilter packet queue handler");
938 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
939 MODULE_LICENSE("GPL");
940 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE);
941
942 module_init(nfnetlink_queue_init);
943 module_exit(nfnetlink_queue_fini);
CRIS linux kernel tree