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