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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc
[cris-mirror.git] / net / netfilter / nfnetlink_queue.c
blobb83123f12b42e30612481796bc6c9a4d3bacab60
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 = -ENOBUFS;
391
392 /* rcu_read_lock()ed by nf_hook_slow() */
393 queue = instance_lookup(queuenum);
394 if (!queue) {
395 err = -ESRCH;
396 goto err_out;
397 }
398
399 if (queue->copy_mode == NFQNL_COPY_NONE) {
400 err = -EINVAL;
401 goto err_out;
402 }
403
404 nskb = nfqnl_build_packet_message(queue, entry);
405 if (nskb == NULL) {
406 err = -ENOMEM;
407 goto err_out;
408 }
409 spin_lock_bh(&queue->lock);
410
411 if (!queue->peer_pid) {
412 err = -EINVAL;
413 goto err_out_free_nskb;
414 }
415 if (queue->queue_total >= queue->queue_maxlen) {
416 queue->queue_dropped++;
417 if (net_ratelimit())
418 printk(KERN_WARNING "nf_queue: full at %d entries, "
419 "dropping packets(s).\n",
420 queue->queue_total);
421 goto err_out_free_nskb;
422 }
423
424 /* nfnetlink_unicast will either free the nskb or add it to a socket */
425 err = nfnetlink_unicast(nskb, &init_net, queue->peer_pid, MSG_DONTWAIT);
426 if (err < 0) {
427 queue->queue_user_dropped++;
428 goto err_out_unlock;
429 }
430
431 __enqueue_entry(queue, entry);
432
433 spin_unlock_bh(&queue->lock);
434 return 0;
435
436 err_out_free_nskb:
437 kfree_skb(nskb);
438 err_out_unlock:
439 spin_unlock_bh(&queue->lock);
440 err_out:
441 return err;
442 }
443
444 static int
445 nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e)
446 {
447 struct sk_buff *nskb;
448 int diff;
449
450 diff = data_len - e->skb->len;
451 if (diff < 0) {
452 if (pskb_trim(e->skb, data_len))
453 return -ENOMEM;
454 } else if (diff > 0) {
455 if (data_len > 0xFFFF)
456 return -EINVAL;
457 if (diff > skb_tailroom(e->skb)) {
458 nskb = skb_copy_expand(e->skb, skb_headroom(e->skb),
459 diff, GFP_ATOMIC);
460 if (!nskb) {
461 printk(KERN_WARNING "nf_queue: OOM "
462 "in mangle, dropping packet\n");
463 return -ENOMEM;
464 }
465 kfree_skb(e->skb);
466 e->skb = nskb;
467 }
468 skb_put(e->skb, diff);
469 }
470 if (!skb_make_writable(e->skb, data_len))
471 return -ENOMEM;
472 skb_copy_to_linear_data(e->skb, data, data_len);
473 e->skb->ip_summed = CHECKSUM_NONE;
474 return 0;
475 }
476
477 static int
478 nfqnl_set_mode(struct nfqnl_instance *queue,
479 unsigned char mode, unsigned int range)
480 {
481 int status = 0;
482
483 spin_lock_bh(&queue->lock);
484 switch (mode) {
485 case NFQNL_COPY_NONE:
486 case NFQNL_COPY_META:
487 queue->copy_mode = mode;
488 queue->copy_range = 0;
489 break;
490
491 case NFQNL_COPY_PACKET:
492 queue->copy_mode = mode;
493 /* we're using struct nlattr which has 16bit nla_len */
494 if (range > 0xffff)
495 queue->copy_range = 0xffff;
496 else
497 queue->copy_range = range;
498 break;
499
500 default:
501 status = -EINVAL;
502
503 }
504 spin_unlock_bh(&queue->lock);
505
506 return status;
507 }
508
509 static int
510 dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex)
511 {
512 if (entry->indev)
513 if (entry->indev->ifindex == ifindex)
514 return 1;
515 if (entry->outdev)
516 if (entry->outdev->ifindex == ifindex)
517 return 1;
518 #ifdef CONFIG_BRIDGE_NETFILTER
519 if (entry->skb->nf_bridge) {
520 if (entry->skb->nf_bridge->physindev &&
521 entry->skb->nf_bridge->physindev->ifindex == ifindex)
522 return 1;
523 if (entry->skb->nf_bridge->physoutdev &&
524 entry->skb->nf_bridge->physoutdev->ifindex == ifindex)
525 return 1;
526 }
527 #endif
528 return 0;
529 }
530
531 /* drop all packets with either indev or outdev == ifindex from all queue
532 * instances */
533 static void
534 nfqnl_dev_drop(int ifindex)
535 {
536 int i;
537
538 rcu_read_lock();
539
540 for (i = 0; i < INSTANCE_BUCKETS; i++) {
541 struct hlist_node *tmp;
542 struct nfqnl_instance *inst;
543 struct hlist_head *head = &instance_table[i];
544
545 hlist_for_each_entry_rcu(inst, tmp, head, hlist)
546 nfqnl_flush(inst, dev_cmp, ifindex);
547 }
548
549 rcu_read_unlock();
550 }
551
552 #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
553
554 static int
555 nfqnl_rcv_dev_event(struct notifier_block *this,
556 unsigned long event, void *ptr)
557 {
558 struct net_device *dev = ptr;
559
560 if (!net_eq(dev_net(dev), &init_net))
561 return NOTIFY_DONE;
562
563 /* Drop any packets associated with the downed device */
564 if (event == NETDEV_DOWN)
565 nfqnl_dev_drop(dev->ifindex);
566 return NOTIFY_DONE;
567 }
568
569 static struct notifier_block nfqnl_dev_notifier = {
570 .notifier_call = nfqnl_rcv_dev_event,
571 };
572
573 static int
574 nfqnl_rcv_nl_event(struct notifier_block *this,
575 unsigned long event, void *ptr)
576 {
577 struct netlink_notify *n = ptr;
578
579 if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
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 const struct nlmsghdr *nlh,
613 const struct nlattr * const nfqa[])
614 {
615 struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
616 u_int16_t queue_num = ntohs(nfmsg->res_id);
617
618 struct nfqnl_msg_verdict_hdr *vhdr;
619 struct nfqnl_instance *queue;
620 unsigned int verdict;
621 struct nf_queue_entry *entry;
622 int err;
623
624 rcu_read_lock();
625 queue = instance_lookup(queue_num);
626 if (!queue) {
627 err = -ENODEV;
628 goto err_out_unlock;
629 }
630
631 if (queue->peer_pid != NETLINK_CB(skb).pid) {
632 err = -EPERM;
633 goto err_out_unlock;
634 }
635
636 if (!nfqa[NFQA_VERDICT_HDR]) {
637 err = -EINVAL;
638 goto err_out_unlock;
639 }
640
641 vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]);
642 verdict = ntohl(vhdr->verdict);
643
644 if ((verdict & NF_VERDICT_MASK) > NF_MAX_VERDICT) {
645 err = -EINVAL;
646 goto err_out_unlock;
647 }
648
649 entry = find_dequeue_entry(queue, ntohl(vhdr->id));
650 if (entry == NULL) {
651 err = -ENOENT;
652 goto err_out_unlock;
653 }
654 rcu_read_unlock();
655
656 if (nfqa[NFQA_PAYLOAD]) {
657 if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),
658 nla_len(nfqa[NFQA_PAYLOAD]), entry) < 0)
659 verdict = NF_DROP;
660 }
661
662 if (nfqa[NFQA_MARK])
663 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
664
665 nf_reinject(entry, verdict);
666 return 0;
667
668 err_out_unlock:
669 rcu_read_unlock();
670 return err;
671 }
672
673 static int
674 nfqnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb,
675 const struct nlmsghdr *nlh,
676 const struct nlattr * const nfqa[])
677 {
678 return -ENOTSUPP;
679 }
680
681 static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = {
682 [NFQA_CFG_CMD] = { .len = sizeof(struct nfqnl_msg_config_cmd) },
683 [NFQA_CFG_PARAMS] = { .len = sizeof(struct nfqnl_msg_config_params) },
684 };
685
686 static const struct nf_queue_handler nfqh = {
687 .name = "nf_queue",
688 .outfn = &nfqnl_enqueue_packet,
689 };
690
691 static int
692 nfqnl_recv_config(struct sock *ctnl, struct sk_buff *skb,
693 const struct nlmsghdr *nlh,
694 const struct nlattr * const nfqa[])
695 {
696 struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
697 u_int16_t queue_num = ntohs(nfmsg->res_id);
698 struct nfqnl_instance *queue;
699 struct nfqnl_msg_config_cmd *cmd = NULL;
700 int ret = 0;
701
702 if (nfqa[NFQA_CFG_CMD]) {
703 cmd = nla_data(nfqa[NFQA_CFG_CMD]);
704
705 /* Commands without queue context - might sleep */
706 switch (cmd->command) {
707 case NFQNL_CFG_CMD_PF_BIND:
708 return nf_register_queue_handler(ntohs(cmd->pf),
709 &nfqh);
710 case NFQNL_CFG_CMD_PF_UNBIND:
711 return nf_unregister_queue_handler(ntohs(cmd->pf),
712 &nfqh);
713 }
714 }
715
716 rcu_read_lock();
717 queue = instance_lookup(queue_num);
718 if (queue && queue->peer_pid != NETLINK_CB(skb).pid) {
719 ret = -EPERM;
720 goto err_out_unlock;
721 }
722
723 if (cmd != NULL) {
724 switch (cmd->command) {
725 case NFQNL_CFG_CMD_BIND:
726 if (queue) {
727 ret = -EBUSY;
728 goto err_out_unlock;
729 }
730 queue = instance_create(queue_num, NETLINK_CB(skb).pid);
731 if (IS_ERR(queue)) {
732 ret = PTR_ERR(queue);
733 goto err_out_unlock;
734 }
735 break;
736 case NFQNL_CFG_CMD_UNBIND:
737 if (!queue) {
738 ret = -ENODEV;
739 goto err_out_unlock;
740 }
741 instance_destroy(queue);
742 break;
743 case NFQNL_CFG_CMD_PF_BIND:
744 case NFQNL_CFG_CMD_PF_UNBIND:
745 break;
746 default:
747 ret = -ENOTSUPP;
748 break;
749 }
750 }
751
752 if (nfqa[NFQA_CFG_PARAMS]) {
753 struct nfqnl_msg_config_params *params;
754
755 if (!queue) {
756 ret = -ENODEV;
757 goto err_out_unlock;
758 }
759 params = nla_data(nfqa[NFQA_CFG_PARAMS]);
760 nfqnl_set_mode(queue, params->copy_mode,
761 ntohl(params->copy_range));
762 }
763
764 if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) {
765 __be32 *queue_maxlen;
766
767 if (!queue) {
768 ret = -ENODEV;
769 goto err_out_unlock;
770 }
771 queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]);
772 spin_lock_bh(&queue->lock);
773 queue->queue_maxlen = ntohl(*queue_maxlen);
774 spin_unlock_bh(&queue->lock);
775 }
776
777 err_out_unlock:
778 rcu_read_unlock();
779 return ret;
780 }
781
782 static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
783 [NFQNL_MSG_PACKET] = { .call = nfqnl_recv_unsupp,
784 .attr_count = NFQA_MAX, },
785 [NFQNL_MSG_VERDICT] = { .call = nfqnl_recv_verdict,
786 .attr_count = NFQA_MAX,
787 .policy = nfqa_verdict_policy },
788 [NFQNL_MSG_CONFIG] = { .call = nfqnl_recv_config,
789 .attr_count = NFQA_CFG_MAX,
790 .policy = nfqa_cfg_policy },
791 };
792
793 static const struct nfnetlink_subsystem nfqnl_subsys = {
794 .name = "nf_queue",
795 .subsys_id = NFNL_SUBSYS_QUEUE,
796 .cb_count = NFQNL_MSG_MAX,
797 .cb = nfqnl_cb,
798 };
799
800 #ifdef CONFIG_PROC_FS
801 struct iter_state {
802 unsigned int bucket;
803 };
804
805 static struct hlist_node *get_first(struct seq_file *seq)
806 {
807 struct iter_state *st = seq->private;
808
809 if (!st)
810 return NULL;
811
812 for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
813 if (!hlist_empty(&instance_table[st->bucket]))
814 return instance_table[st->bucket].first;
815 }
816 return NULL;
817 }
818
819 static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h)
820 {
821 struct iter_state *st = seq->private;
822
823 h = h->next;
824 while (!h) {
825 if (++st->bucket >= INSTANCE_BUCKETS)
826 return NULL;
827
828 h = instance_table[st->bucket].first;
829 }
830 return h;
831 }
832
833 static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos)
834 {
835 struct hlist_node *head;
836 head = get_first(seq);
837
838 if (head)
839 while (pos && (head = get_next(seq, head)))
840 pos--;
841 return pos ? NULL : head;
842 }
843
844 static void *seq_start(struct seq_file *seq, loff_t *pos)
845 __acquires(instances_lock)
846 {
847 spin_lock(&instances_lock);
848 return get_idx(seq, *pos);
849 }
850
851 static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
852 {
853 (*pos)++;
854 return get_next(s, v);
855 }
856
857 static void seq_stop(struct seq_file *s, void *v)
858 __releases(instances_lock)
859 {
860 spin_unlock(&instances_lock);
861 }
862
863 static int seq_show(struct seq_file *s, void *v)
864 {
865 const struct nfqnl_instance *inst = v;
866
867 return seq_printf(s, "%5d %6d %5d %1d %5d %5d %5d %8d %2d\n",
868 inst->queue_num,
869 inst->peer_pid, inst->queue_total,
870 inst->copy_mode, inst->copy_range,
871 inst->queue_dropped, inst->queue_user_dropped,
872 atomic_read(&inst->id_sequence), 1);
873 }
874
875 static const struct seq_operations nfqnl_seq_ops = {
876 .start = seq_start,
877 .next = seq_next,
878 .stop = seq_stop,
879 .show = seq_show,
880 };
881
882 static int nfqnl_open(struct inode *inode, struct file *file)
883 {
884 return seq_open_private(file, &nfqnl_seq_ops,
885 sizeof(struct iter_state));
886 }
887
888 static const struct file_operations nfqnl_file_ops = {
889 .owner = THIS_MODULE,
890 .open = nfqnl_open,
891 .read = seq_read,
892 .llseek = seq_lseek,
893 .release = seq_release_private,
894 };
895
896 #endif /* PROC_FS */
897
898 static int __init nfnetlink_queue_init(void)
899 {
900 int i, status = -ENOMEM;
901
902 for (i = 0; i < INSTANCE_BUCKETS; i++)
903 INIT_HLIST_HEAD(&instance_table[i]);
904
905 netlink_register_notifier(&nfqnl_rtnl_notifier);
906 status = nfnetlink_subsys_register(&nfqnl_subsys);
907 if (status < 0) {
908 printk(KERN_ERR "nf_queue: failed to create netlink socket\n");
909 goto cleanup_netlink_notifier;
910 }
911
912 #ifdef CONFIG_PROC_FS
913 if (!proc_create("nfnetlink_queue", 0440,
914 proc_net_netfilter, &nfqnl_file_ops))
915 goto cleanup_subsys;
916 #endif
917
918 register_netdevice_notifier(&nfqnl_dev_notifier);
919 return status;
920
921 #ifdef CONFIG_PROC_FS
922 cleanup_subsys:
923 nfnetlink_subsys_unregister(&nfqnl_subsys);
924 #endif
925 cleanup_netlink_notifier:
926 netlink_unregister_notifier(&nfqnl_rtnl_notifier);
927 return status;
928 }
929
930 static void __exit nfnetlink_queue_fini(void)
931 {
932 nf_unregister_queue_handlers(&nfqh);
933 unregister_netdevice_notifier(&nfqnl_dev_notifier);
934 #ifdef CONFIG_PROC_FS
935 remove_proc_entry("nfnetlink_queue", proc_net_netfilter);
936 #endif
937 nfnetlink_subsys_unregister(&nfqnl_subsys);
938 netlink_unregister_notifier(&nfqnl_rtnl_notifier);
939
940 rcu_barrier(); /* Wait for completion of call_rcu()'s */
941 }
942
943 MODULE_DESCRIPTION("netfilter packet queue handler");
944 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
945 MODULE_LICENSE("GPL");
946 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE);
947
948 module_init(nfnetlink_queue_init);
949 module_exit(nfnetlink_queue_fini);
CRIS linux kernel tree