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-rw-r--r--net/netfilter/nfnetlink_queue.c1028
1 files changed, 1028 insertions, 0 deletions
diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
new file mode 100644
index 00000000000..a80b0cb03f1
--- /dev/null
+++ b/net/netfilter/nfnetlink_queue.c
@@ -0,0 +1,1028 @@
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 <linux/atomic.h>
35
36#ifdef CONFIG_BRIDGE_NETFILTER
37#include "../bridge/br_private.h"
38#endif
39
40#define NFQNL_QMAX_DEFAULT 1024
41
42struct 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 unsigned int id_sequence; /* 'sequence' of pkt ids */
62 struct list_head queue_list; /* packets in queue */
63};
64
65typedef int (*nfqnl_cmpfn)(struct nf_queue_entry *, unsigned long);
66
67static DEFINE_SPINLOCK(instances_lock);
68
69#define INSTANCE_BUCKETS 16
70static struct hlist_head instance_table[INSTANCE_BUCKETS] __read_mostly;
71
72static inline u_int8_t instance_hashfn(u_int16_t queue_num)
73{
74 return ((queue_num >> 8) | queue_num) % INSTANCE_BUCKETS;
75}
76
77static struct nfqnl_instance *
78instance_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
92static struct nfqnl_instance *
93instance_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
131out_free:
132 kfree(inst);
133out_unlock:
134 spin_unlock(&instances_lock);
135 return ERR_PTR(err);
136}
137
138static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
139 unsigned long data);
140
141static void
142instance_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
152static 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
159static void
160instance_destroy(struct nfqnl_instance *inst)
161{
162 spin_lock(&instances_lock);
163 __instance_destroy(inst);
164 spin_unlock(&instances_lock);
165}
166
167static 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
174static void
175__dequeue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
176{
177 list_del(&entry->list);
178 queue->queue_total--;
179}
180
181static struct nf_queue_entry *
182find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id)
183{
184 struct nf_queue_entry *entry = NULL, *i;
185
186 spin_lock_bh(&queue->lock);
187
188 list_for_each_entry(i, &queue->queue_list, list) {
189 if (i->id == id) {
190 entry = i;
191 break;
192 }
193 }
194
195 if (entry)
196 __dequeue_entry(queue, entry);
197
198 spin_unlock_bh(&queue->lock);
199
200 return entry;
201}
202
203static void
204nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data)
205{
206 struct nf_queue_entry *entry, *next;
207
208 spin_lock_bh(&queue->lock);
209 list_for_each_entry_safe(entry, next, &queue->queue_list, list) {
210 if (!cmpfn || cmpfn(entry, data)) {
211 list_del(&entry->list);
212 queue->queue_total--;
213 nf_reinject(entry, NF_DROP);
214 }
215 }
216 spin_unlock_bh(&queue->lock);
217}
218
219static struct sk_buff *
220nfqnl_build_packet_message(struct nfqnl_instance *queue,
221 struct nf_queue_entry *entry,
222 __be32 **packet_id_ptr)
223{
224 sk_buff_data_t old_tail;
225 size_t size;
226 size_t data_len = 0;
227 struct sk_buff *skb;
228 struct nlattr *nla;
229 struct nfqnl_msg_packet_hdr *pmsg;
230 struct nlmsghdr *nlh;
231 struct nfgenmsg *nfmsg;
232 struct sk_buff *entskb = entry->skb;
233 struct net_device *indev;
234 struct net_device *outdev;
235
236 size = NLMSG_SPACE(sizeof(struct nfgenmsg))
237 + nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))
238 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
239 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
240#ifdef CONFIG_BRIDGE_NETFILTER
241 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
242 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
243#endif
244 + nla_total_size(sizeof(u_int32_t)) /* mark */
245 + nla_total_size(sizeof(struct nfqnl_msg_packet_hw))
246 + nla_total_size(sizeof(struct nfqnl_msg_packet_timestamp));
247
248 outdev = entry->outdev;
249
250 switch ((enum nfqnl_config_mode)ACCESS_ONCE(queue->copy_mode)) {
251 case NFQNL_COPY_META:
252 case NFQNL_COPY_NONE:
253 break;
254
255 case NFQNL_COPY_PACKET:
256 if (entskb->ip_summed == CHECKSUM_PARTIAL &&
257 skb_checksum_help(entskb))
258 return NULL;
259
260 data_len = ACCESS_ONCE(queue->copy_range);
261 if (data_len == 0 || data_len > entskb->len)
262 data_len = entskb->len;
263
264 size += nla_total_size(data_len);
265 break;
266 }
267
268
269 skb = alloc_skb(size, GFP_ATOMIC);
270 if (!skb)
271 goto nlmsg_failure;
272
273 old_tail = skb->tail;
274 nlh = NLMSG_PUT(skb, 0, 0,
275 NFNL_SUBSYS_QUEUE << 8 | NFQNL_MSG_PACKET,
276 sizeof(struct nfgenmsg));
277 nfmsg = NLMSG_DATA(nlh);
278 nfmsg->nfgen_family = entry->pf;
279 nfmsg->version = NFNETLINK_V0;
280 nfmsg->res_id = htons(queue->queue_num);
281
282 nla = __nla_reserve(skb, NFQA_PACKET_HDR, sizeof(*pmsg));
283 pmsg = nla_data(nla);
284 pmsg->hw_protocol = entskb->protocol;
285 pmsg->hook = entry->hook;
286 *packet_id_ptr = &pmsg->packet_id;
287
288 indev = entry->indev;
289 if (indev) {
290#ifndef CONFIG_BRIDGE_NETFILTER
291 NLA_PUT_BE32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex));
292#else
293 if (entry->pf == PF_BRIDGE) {
294 /* Case 1: indev is physical input device, we need to
295 * look for bridge group (when called from
296 * netfilter_bridge) */
297 NLA_PUT_BE32(skb, NFQA_IFINDEX_PHYSINDEV,
298 htonl(indev->ifindex));
299 /* this is the bridge group "brX" */
300 /* rcu_read_lock()ed by __nf_queue */
301 NLA_PUT_BE32(skb, NFQA_IFINDEX_INDEV,
302 htonl(br_port_get_rcu(indev)->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 /* rcu_read_lock()ed by __nf_queue */
327 NLA_PUT_BE32(skb, NFQA_IFINDEX_OUTDEV,
328 htonl(br_port_get_rcu(outdev)->br->dev->ifindex));
329 } else {
330 /* Case 2: outdev is bridge group, we need to look for
331 * physical output device (when called from ipv4) */
332 NLA_PUT_BE32(skb, NFQA_IFINDEX_OUTDEV,
333 htonl(outdev->ifindex));
334 if (entskb->nf_bridge && entskb->nf_bridge->physoutdev)
335 NLA_PUT_BE32(skb, NFQA_IFINDEX_PHYSOUTDEV,
336 htonl(entskb->nf_bridge->physoutdev->ifindex));
337 }
338#endif
339 }
340
341 if (entskb->mark)
342 NLA_PUT_BE32(skb, NFQA_MARK, htonl(entskb->mark));
343
344 if (indev && entskb->dev &&
345 entskb->mac_header != entskb->network_header) {
346 struct nfqnl_msg_packet_hw phw;
347 int len = dev_parse_header(entskb, phw.hw_addr);
348 if (len) {
349 phw.hw_addrlen = htons(len);
350 NLA_PUT(skb, NFQA_HWADDR, sizeof(phw), &phw);
351 }
352 }
353
354 if (entskb->tstamp.tv64) {
355 struct nfqnl_msg_packet_timestamp ts;
356 struct timeval tv = ktime_to_timeval(entskb->tstamp);
357 ts.sec = cpu_to_be64(tv.tv_sec);
358 ts.usec = cpu_to_be64(tv.tv_usec);
359
360 NLA_PUT(skb, NFQA_TIMESTAMP, sizeof(ts), &ts);
361 }
362
363 if (data_len) {
364 struct nlattr *nla;
365 int sz = nla_attr_size(data_len);
366
367 if (skb_tailroom(skb) < nla_total_size(data_len)) {
368 printk(KERN_WARNING "nf_queue: no tailroom!\n");
369 goto nlmsg_failure;
370 }
371
372 nla = (struct nlattr *)skb_put(skb, nla_total_size(data_len));
373 nla->nla_type = NFQA_PAYLOAD;
374 nla->nla_len = sz;
375
376 if (skb_copy_bits(entskb, 0, nla_data(nla), data_len))
377 BUG();
378 }
379
380 nlh->nlmsg_len = skb->tail - old_tail;
381 return skb;
382
383nlmsg_failure:
384nla_put_failure:
385 if (skb)
386 kfree_skb(skb);
387 if (net_ratelimit())
388 printk(KERN_ERR "nf_queue: error creating packet message\n");
389 return NULL;
390}
391
392static int
393nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
394{
395 struct sk_buff *nskb;
396 struct nfqnl_instance *queue;
397 int err = -ENOBUFS;
398 __be32 *packet_id_ptr;
399
400 /* rcu_read_lock()ed by nf_hook_slow() */
401 queue = instance_lookup(queuenum);
402 if (!queue) {
403 err = -ESRCH;
404 goto err_out;
405 }
406
407 if (queue->copy_mode == NFQNL_COPY_NONE) {
408 err = -EINVAL;
409 goto err_out;
410 }
411
412 nskb = nfqnl_build_packet_message(queue, entry, &packet_id_ptr);
413 if (nskb == NULL) {
414 err = -ENOMEM;
415 goto err_out;
416 }
417 spin_lock_bh(&queue->lock);
418
419 if (!queue->peer_pid) {
420 err = -EINVAL;
421 goto err_out_free_nskb;
422 }
423 if (queue->queue_total >= queue->queue_maxlen) {
424 queue->queue_dropped++;
425 if (net_ratelimit())
426 printk(KERN_WARNING "nf_queue: full at %d entries, "
427 "dropping packets(s).\n",
428 queue->queue_total);
429 goto err_out_free_nskb;
430 }
431 entry->id = ++queue->id_sequence;
432 *packet_id_ptr = htonl(entry->id);
433
434 /* nfnetlink_unicast will either free the nskb or add it to a socket */
435 err = nfnetlink_unicast(nskb, &init_net, queue->peer_pid, MSG_DONTWAIT);
436 if (err < 0) {
437 queue->queue_user_dropped++;
438 goto err_out_unlock;
439 }
440
441 __enqueue_entry(queue, entry);
442
443 spin_unlock_bh(&queue->lock);
444 return 0;
445
446err_out_free_nskb:
447 kfree_skb(nskb);
448err_out_unlock:
449 spin_unlock_bh(&queue->lock);
450err_out:
451 return err;
452}
453
454static int
455nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e)
456{
457 struct sk_buff *nskb;
458 int diff;
459
460 diff = data_len - e->skb->len;
461 if (diff < 0) {
462 if (pskb_trim(e->skb, data_len))
463 return -ENOMEM;
464 } else if (diff > 0) {
465 if (data_len > 0xFFFF)
466 return -EINVAL;
467 if (diff > skb_tailroom(e->skb)) {
468 nskb = skb_copy_expand(e->skb, skb_headroom(e->skb),
469 diff, GFP_ATOMIC);
470 if (!nskb) {
471 printk(KERN_WARNING "nf_queue: OOM "
472 "in mangle, dropping packet\n");
473 return -ENOMEM;
474 }
475 kfree_skb(e->skb);
476 e->skb = nskb;
477 }
478 skb_put(e->skb, diff);
479 }
480 if (!skb_make_writable(e->skb, data_len))
481 return -ENOMEM;
482 skb_copy_to_linear_data(e->skb, data, data_len);
483 e->skb->ip_summed = CHECKSUM_NONE;
484 return 0;
485}
486
487static int
488nfqnl_set_mode(struct nfqnl_instance *queue,
489 unsigned char mode, unsigned int range)
490{
491 int status = 0;
492
493 spin_lock_bh(&queue->lock);
494 switch (mode) {
495 case NFQNL_COPY_NONE:
496 case NFQNL_COPY_META:
497 queue->copy_mode = mode;
498 queue->copy_range = 0;
499 break;
500
501 case NFQNL_COPY_PACKET:
502 queue->copy_mode = mode;
503 /* we're using struct nlattr which has 16bit nla_len */
504 if (range > 0xffff)
505 queue->copy_range = 0xffff;
506 else
507 queue->copy_range = range;
508 break;
509
510 default:
511 status = -EINVAL;
512
513 }
514 spin_unlock_bh(&queue->lock);
515
516 return status;
517}
518
519static int
520dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex)
521{
522 if (entry->indev)
523 if (entry->indev->ifindex == ifindex)
524 return 1;
525 if (entry->outdev)
526 if (entry->outdev->ifindex == ifindex)
527 return 1;
528#ifdef CONFIG_BRIDGE_NETFILTER
529 if (entry->skb->nf_bridge) {
530 if (entry->skb->nf_bridge->physindev &&
531 entry->skb->nf_bridge->physindev->ifindex == ifindex)
532 return 1;
533 if (entry->skb->nf_bridge->physoutdev &&
534 entry->skb->nf_bridge->physoutdev->ifindex == ifindex)
535 return 1;
536 }
537#endif
538 return 0;
539}
540
541/* drop all packets with either indev or outdev == ifindex from all queue
542 * instances */
543static void
544nfqnl_dev_drop(int ifindex)
545{
546 int i;
547
548 rcu_read_lock();
549
550 for (i = 0; i < INSTANCE_BUCKETS; i++) {
551 struct hlist_node *tmp;
552 struct nfqnl_instance *inst;
553 struct hlist_head *head = &instance_table[i];
554
555 hlist_for_each_entry_rcu(inst, tmp, head, hlist)
556 nfqnl_flush(inst, dev_cmp, ifindex);
557 }
558
559 rcu_read_unlock();
560}
561
562#define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
563
564static int
565nfqnl_rcv_dev_event(struct notifier_block *this,
566 unsigned long event, void *ptr)
567{
568 struct net_device *dev = ptr;
569
570 if (!net_eq(dev_net(dev), &init_net))
571 return NOTIFY_DONE;
572
573 /* Drop any packets associated with the downed device */
574 if (event == NETDEV_DOWN)
575 nfqnl_dev_drop(dev->ifindex);
576 return NOTIFY_DONE;
577}
578
579static struct notifier_block nfqnl_dev_notifier = {
580 .notifier_call = nfqnl_rcv_dev_event,
581};
582
583static int
584nfqnl_rcv_nl_event(struct notifier_block *this,
585 unsigned long event, void *ptr)
586{
587 struct netlink_notify *n = ptr;
588
589 if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
590 int i;
591
592 /* destroy all instances for this pid */
593 spin_lock(&instances_lock);
594 for (i = 0; i < INSTANCE_BUCKETS; i++) {
595 struct hlist_node *tmp, *t2;
596 struct nfqnl_instance *inst;
597 struct hlist_head *head = &instance_table[i];
598
599 hlist_for_each_entry_safe(inst, tmp, t2, head, hlist) {
600 if ((n->net == &init_net) &&
601 (n->pid == inst->peer_pid))
602 __instance_destroy(inst);
603 }
604 }
605 spin_unlock(&instances_lock);
606 }
607 return NOTIFY_DONE;
608}
609
610static struct notifier_block nfqnl_rtnl_notifier = {
611 .notifier_call = nfqnl_rcv_nl_event,
612};
613
614static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = {
615 [NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
616 [NFQA_MARK] = { .type = NLA_U32 },
617 [NFQA_PAYLOAD] = { .type = NLA_UNSPEC },
618};
619
620static const struct nla_policy nfqa_verdict_batch_policy[NFQA_MAX+1] = {
621 [NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
622 [NFQA_MARK] = { .type = NLA_U32 },
623};
624
625static struct nfqnl_instance *verdict_instance_lookup(u16 queue_num, int nlpid)
626{
627 struct nfqnl_instance *queue;
628
629 queue = instance_lookup(queue_num);
630 if (!queue)
631 return ERR_PTR(-ENODEV);
632
633 if (queue->peer_pid != nlpid)
634 return ERR_PTR(-EPERM);
635
636 return queue;
637}
638
639static struct nfqnl_msg_verdict_hdr*
640verdicthdr_get(const struct nlattr * const nfqa[])
641{
642 struct nfqnl_msg_verdict_hdr *vhdr;
643 unsigned int verdict;
644
645 if (!nfqa[NFQA_VERDICT_HDR])
646 return NULL;
647
648 vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]);
649 verdict = ntohl(vhdr->verdict) & NF_VERDICT_MASK;
650 if (verdict > NF_MAX_VERDICT || verdict == NF_STOLEN)
651 return NULL;
652 return vhdr;
653}
654
655static int nfq_id_after(unsigned int id, unsigned int max)
656{
657 return (int)(id - max) > 0;
658}
659
660static int
661nfqnl_recv_verdict_batch(struct sock *ctnl, struct sk_buff *skb,
662 const struct nlmsghdr *nlh,
663 const struct nlattr * const nfqa[])
664{
665 struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
666 struct nf_queue_entry *entry, *tmp;
667 unsigned int verdict, maxid;
668 struct nfqnl_msg_verdict_hdr *vhdr;
669 struct nfqnl_instance *queue;
670 LIST_HEAD(batch_list);
671 u16 queue_num = ntohs(nfmsg->res_id);
672
673 queue = verdict_instance_lookup(queue_num, NETLINK_CB(skb).pid);
674 if (IS_ERR(queue))
675 return PTR_ERR(queue);
676
677 vhdr = verdicthdr_get(nfqa);
678 if (!vhdr)
679 return -EINVAL;
680
681 verdict = ntohl(vhdr->verdict);
682 maxid = ntohl(vhdr->id);
683
684 spin_lock_bh(&queue->lock);
685
686 list_for_each_entry_safe(entry, tmp, &queue->queue_list, list) {
687 if (nfq_id_after(entry->id, maxid))
688 break;
689 __dequeue_entry(queue, entry);
690 list_add_tail(&entry->list, &batch_list);
691 }
692
693 spin_unlock_bh(&queue->lock);
694
695 if (list_empty(&batch_list))
696 return -ENOENT;
697
698 list_for_each_entry_safe(entry, tmp, &batch_list, list) {
699 if (nfqa[NFQA_MARK])
700 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
701 nf_reinject(entry, verdict);
702 }
703 return 0;
704}
705
706static int
707nfqnl_recv_verdict(struct sock *ctnl, struct sk_buff *skb,
708 const struct nlmsghdr *nlh,
709 const struct nlattr * const nfqa[])
710{
711 struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
712 u_int16_t queue_num = ntohs(nfmsg->res_id);
713
714 struct nfqnl_msg_verdict_hdr *vhdr;
715 struct nfqnl_instance *queue;
716 unsigned int verdict;
717 struct nf_queue_entry *entry;
718
719 queue = instance_lookup(queue_num);
720 if (!queue)
721
722 queue = verdict_instance_lookup(queue_num, NETLINK_CB(skb).pid);
723 if (IS_ERR(queue))
724 return PTR_ERR(queue);
725
726 vhdr = verdicthdr_get(nfqa);
727 if (!vhdr)
728 return -EINVAL;
729
730 verdict = ntohl(vhdr->verdict);
731
732 entry = find_dequeue_entry(queue, ntohl(vhdr->id));
733 if (entry == NULL)
734 return -ENOENT;
735
736 if (nfqa[NFQA_PAYLOAD]) {
737 if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),
738 nla_len(nfqa[NFQA_PAYLOAD]), entry) < 0)
739 verdict = NF_DROP;
740 }
741
742 if (nfqa[NFQA_MARK])
743 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
744
745 nf_reinject(entry, verdict);
746 return 0;
747}
748
749static int
750nfqnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb,
751 const struct nlmsghdr *nlh,
752 const struct nlattr * const nfqa[])
753{
754 return -ENOTSUPP;
755}
756
757static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = {
758 [NFQA_CFG_CMD] = { .len = sizeof(struct nfqnl_msg_config_cmd) },
759 [NFQA_CFG_PARAMS] = { .len = sizeof(struct nfqnl_msg_config_params) },
760};
761
762static const struct nf_queue_handler nfqh = {
763 .name = "nf_queue",
764 .outfn = &nfqnl_enqueue_packet,
765};
766
767static int
768nfqnl_recv_config(struct sock *ctnl, struct sk_buff *skb,
769 const struct nlmsghdr *nlh,
770 const struct nlattr * const nfqa[])
771{
772 struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
773 u_int16_t queue_num = ntohs(nfmsg->res_id);
774 struct nfqnl_instance *queue;
775 struct nfqnl_msg_config_cmd *cmd = NULL;
776 int ret = 0;
777
778 if (nfqa[NFQA_CFG_CMD]) {
779 cmd = nla_data(nfqa[NFQA_CFG_CMD]);
780
781 /* Commands without queue context - might sleep */
782 switch (cmd->command) {
783 case NFQNL_CFG_CMD_PF_BIND:
784 return nf_register_queue_handler(ntohs(cmd->pf),
785 &nfqh);
786 case NFQNL_CFG_CMD_PF_UNBIND:
787 return nf_unregister_queue_handler(ntohs(cmd->pf),
788 &nfqh);
789 }
790 }
791
792 rcu_read_lock();
793 queue = instance_lookup(queue_num);
794 if (queue && queue->peer_pid != NETLINK_CB(skb).pid) {
795 ret = -EPERM;
796 goto err_out_unlock;
797 }
798
799 if (cmd != NULL) {
800 switch (cmd->command) {
801 case NFQNL_CFG_CMD_BIND:
802 if (queue) {
803 ret = -EBUSY;
804 goto err_out_unlock;
805 }
806 queue = instance_create(queue_num, NETLINK_CB(skb).pid);
807 if (IS_ERR(queue)) {
808 ret = PTR_ERR(queue);
809 goto err_out_unlock;
810 }
811 break;
812 case NFQNL_CFG_CMD_UNBIND:
813 if (!queue) {
814 ret = -ENODEV;
815 goto err_out_unlock;
816 }
817 instance_destroy(queue);
818 break;
819 case NFQNL_CFG_CMD_PF_BIND:
820 case NFQNL_CFG_CMD_PF_UNBIND:
821 break;
822 default:
823 ret = -ENOTSUPP;
824 break;
825 }
826 }
827
828 if (nfqa[NFQA_CFG_PARAMS]) {
829 struct nfqnl_msg_config_params *params;
830
831 if (!queue) {
832 ret = -ENODEV;
833 goto err_out_unlock;
834 }
835 params = nla_data(nfqa[NFQA_CFG_PARAMS]);
836 nfqnl_set_mode(queue, params->copy_mode,
837 ntohl(params->copy_range));
838 }
839
840 if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) {
841 __be32 *queue_maxlen;
842
843 if (!queue) {
844 ret = -ENODEV;
845 goto err_out_unlock;
846 }
847 queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]);
848 spin_lock_bh(&queue->lock);
849 queue->queue_maxlen = ntohl(*queue_maxlen);
850 spin_unlock_bh(&queue->lock);
851 }
852
853err_out_unlock:
854 rcu_read_unlock();
855 return ret;
856}
857
858static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
859 [NFQNL_MSG_PACKET] = { .call_rcu = nfqnl_recv_unsupp,
860 .attr_count = NFQA_MAX, },
861 [NFQNL_MSG_VERDICT] = { .call_rcu = nfqnl_recv_verdict,
862 .attr_count = NFQA_MAX,
863 .policy = nfqa_verdict_policy },
864 [NFQNL_MSG_CONFIG] = { .call = nfqnl_recv_config,
865 .attr_count = NFQA_CFG_MAX,
866 .policy = nfqa_cfg_policy },
867 [NFQNL_MSG_VERDICT_BATCH]={ .call_rcu = nfqnl_recv_verdict_batch,
868 .attr_count = NFQA_MAX,
869 .policy = nfqa_verdict_batch_policy },
870};
871
872static const struct nfnetlink_subsystem nfqnl_subsys = {
873 .name = "nf_queue",
874 .subsys_id = NFNL_SUBSYS_QUEUE,
875 .cb_count = NFQNL_MSG_MAX,
876 .cb = nfqnl_cb,
877};
878
879#ifdef CONFIG_PROC_FS
880struct iter_state {
881 unsigned int bucket;
882};
883
884static struct hlist_node *get_first(struct seq_file *seq)
885{
886 struct iter_state *st = seq->private;
887
888 if (!st)
889 return NULL;
890
891 for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
892 if (!hlist_empty(&instance_table[st->bucket]))
893 return instance_table[st->bucket].first;
894 }
895 return NULL;
896}
897
898static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h)
899{
900 struct iter_state *st = seq->private;
901
902 h = h->next;
903 while (!h) {
904 if (++st->bucket >= INSTANCE_BUCKETS)
905 return NULL;
906
907 h = instance_table[st->bucket].first;
908 }
909 return h;
910}
911
912static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos)
913{
914 struct hlist_node *head;
915 head = get_first(seq);
916
917 if (head)
918 while (pos && (head = get_next(seq, head)))
919 pos--;
920 return pos ? NULL : head;
921}
922
923static void *seq_start(struct seq_file *seq, loff_t *pos)
924 __acquires(instances_lock)
925{
926 spin_lock(&instances_lock);
927 return get_idx(seq, *pos);
928}
929
930static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
931{
932 (*pos)++;
933 return get_next(s, v);
934}
935
936static void seq_stop(struct seq_file *s, void *v)
937 __releases(instances_lock)
938{
939 spin_unlock(&instances_lock);
940}
941
942static int seq_show(struct seq_file *s, void *v)
943{
944 const struct nfqnl_instance *inst = v;
945
946 return seq_printf(s, "%5d %6d %5d %1d %5d %5d %5d %8d %2d\n",
947 inst->queue_num,
948 inst->peer_pid, inst->queue_total,
949 inst->copy_mode, inst->copy_range,
950 inst->queue_dropped, inst->queue_user_dropped,
951 inst->id_sequence, 1);
952}
953
954static const struct seq_operations nfqnl_seq_ops = {
955 .start = seq_start,
956 .next = seq_next,
957 .stop = seq_stop,
958 .show = seq_show,
959};
960
961static int nfqnl_open(struct inode *inode, struct file *file)
962{
963 return seq_open_private(file, &nfqnl_seq_ops,
964 sizeof(struct iter_state));
965}
966
967static const struct file_operations nfqnl_file_ops = {
968 .owner = THIS_MODULE,
969 .open = nfqnl_open,
970 .read = seq_read,
971 .llseek = seq_lseek,
972 .release = seq_release_private,
973};
974
975#endif /* PROC_FS */
976
977static int __init nfnetlink_queue_init(void)
978{
979 int i, status = -ENOMEM;
980
981 for (i = 0; i < INSTANCE_BUCKETS; i++)
982 INIT_HLIST_HEAD(&instance_table[i]);
983
984 netlink_register_notifier(&nfqnl_rtnl_notifier);
985 status = nfnetlink_subsys_register(&nfqnl_subsys);
986 if (status < 0) {
987 printk(KERN_ERR "nf_queue: failed to create netlink socket\n");
988 goto cleanup_netlink_notifier;
989 }
990
991#ifdef CONFIG_PROC_FS
992 if (!proc_create("nfnetlink_queue", 0440,
993 proc_net_netfilter, &nfqnl_file_ops))
994 goto cleanup_subsys;
995#endif
996
997 register_netdevice_notifier(&nfqnl_dev_notifier);
998 return status;
999
1000#ifdef CONFIG_PROC_FS
1001cleanup_subsys:
1002 nfnetlink_subsys_unregister(&nfqnl_subsys);
1003#endif
1004cleanup_netlink_notifier:
1005 netlink_unregister_notifier(&nfqnl_rtnl_notifier);
1006 return status;
1007}
1008
1009static void __exit nfnetlink_queue_fini(void)
1010{
1011 nf_unregister_queue_handlers(&nfqh);
1012 unregister_netdevice_notifier(&nfqnl_dev_notifier);
1013#ifdef CONFIG_PROC_FS
1014 remove_proc_entry("nfnetlink_queue", proc_net_netfilter);
1015#endif
1016 nfnetlink_subsys_unregister(&nfqnl_subsys);
1017 netlink_unregister_notifier(&nfqnl_rtnl_notifier);
1018
1019 rcu_barrier(); /* Wait for completion of call_rcu()'s */
1020}
1021
1022MODULE_DESCRIPTION("netfilter packet queue handler");
1023MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
1024MODULE_LICENSE("GPL");
1025MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE);
1026
1027module_init(nfnetlink_queue_init);
1028module_exit(nfnetlink_queue_fini);
generated by cgit v1.2.2 (git 2.25.0) at 2025-04-17 08:14:17 -0400