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Merge branch 'acpi-lpss'
[deliverable/linux.git] / net / netfilter / nfnetlink_queue_core.c
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 #include <net/netfilter/nfnetlink_queue.h>
34
35 #include <linux/atomic.h>
36
37 #ifdef CONFIG_BRIDGE_NETFILTER
38 #include "../bridge/br_private.h"
39 #endif
40
41 #define NFQNL_QMAX_DEFAULT 1024
42
43 struct nfqnl_instance {
44 struct hlist_node hlist; /* global list of queues */
45 struct rcu_head rcu;
46
47 int peer_portid;
48 unsigned int queue_maxlen;
49 unsigned int copy_range;
50 unsigned int queue_dropped;
51 unsigned int queue_user_dropped;
52
53
54 u_int16_t queue_num; /* number of this queue */
55 u_int8_t copy_mode;
56 u_int32_t flags; /* Set using NFQA_CFG_FLAGS */
57 /*
58 * Following fields are dirtied for each queued packet,
59 * keep them in same cache line if possible.
60 */
61 spinlock_t lock;
62 unsigned int queue_total;
63 unsigned int id_sequence; /* 'sequence' of pkt ids */
64 struct list_head queue_list; /* packets in queue */
65 };
66
67 typedef int (*nfqnl_cmpfn)(struct nf_queue_entry *, unsigned long);
68
69 static DEFINE_SPINLOCK(instances_lock);
70
71 #define INSTANCE_BUCKETS 16
72 static struct hlist_head instance_table[INSTANCE_BUCKETS] __read_mostly;
73
74 static inline u_int8_t instance_hashfn(u_int16_t queue_num)
75 {
76 return ((queue_num >> 8) | queue_num) % INSTANCE_BUCKETS;
77 }
78
79 static struct nfqnl_instance *
80 instance_lookup(u_int16_t queue_num)
81 {
82 struct hlist_head *head;
83 struct nfqnl_instance *inst;
84
85 head = &instance_table[instance_hashfn(queue_num)];
86 hlist_for_each_entry_rcu(inst, head, hlist) {
87 if (inst->queue_num == queue_num)
88 return inst;
89 }
90 return NULL;
91 }
92
93 static struct nfqnl_instance *
94 instance_create(u_int16_t queue_num, int portid)
95 {
96 struct nfqnl_instance *inst;
97 unsigned int h;
98 int err;
99
100 spin_lock(&instances_lock);
101 if (instance_lookup(queue_num)) {
102 err = -EEXIST;
103 goto out_unlock;
104 }
105
106 inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
107 if (!inst) {
108 err = -ENOMEM;
109 goto out_unlock;
110 }
111
112 inst->queue_num = queue_num;
113 inst->peer_portid = portid;
114 inst->queue_maxlen = NFQNL_QMAX_DEFAULT;
115 inst->copy_range = 0xffff;
116 inst->copy_mode = NFQNL_COPY_NONE;
117 spin_lock_init(&inst->lock);
118 INIT_LIST_HEAD(&inst->queue_list);
119
120 if (!try_module_get(THIS_MODULE)) {
121 err = -EAGAIN;
122 goto out_free;
123 }
124
125 h = instance_hashfn(queue_num);
126 hlist_add_head_rcu(&inst->hlist, &instance_table[h]);
127
128 spin_unlock(&instances_lock);
129
130 return inst;
131
132 out_free:
133 kfree(inst);
134 out_unlock:
135 spin_unlock(&instances_lock);
136 return ERR_PTR(err);
137 }
138
139 static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
140 unsigned long data);
141
142 static void
143 instance_destroy_rcu(struct rcu_head *head)
144 {
145 struct nfqnl_instance *inst = container_of(head, struct nfqnl_instance,
146 rcu);
147
148 nfqnl_flush(inst, NULL, 0);
149 kfree(inst);
150 module_put(THIS_MODULE);
151 }
152
153 static void
154 __instance_destroy(struct nfqnl_instance *inst)
155 {
156 hlist_del_rcu(&inst->hlist);
157 call_rcu(&inst->rcu, instance_destroy_rcu);
158 }
159
160 static void
161 instance_destroy(struct nfqnl_instance *inst)
162 {
163 spin_lock(&instances_lock);
164 __instance_destroy(inst);
165 spin_unlock(&instances_lock);
166 }
167
168 static inline void
169 __enqueue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
170 {
171 list_add_tail(&entry->list, &queue->queue_list);
172 queue->queue_total++;
173 }
174
175 static void
176 __dequeue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
177 {
178 list_del(&entry->list);
179 queue->queue_total--;
180 }
181
182 static struct nf_queue_entry *
183 find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id)
184 {
185 struct nf_queue_entry *entry = NULL, *i;
186
187 spin_lock_bh(&queue->lock);
188
189 list_for_each_entry(i, &queue->queue_list, list) {
190 if (i->id == id) {
191 entry = i;
192 break;
193 }
194 }
195
196 if (entry)
197 __dequeue_entry(queue, entry);
198
199 spin_unlock_bh(&queue->lock);
200
201 return entry;
202 }
203
204 static void
205 nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data)
206 {
207 struct nf_queue_entry *entry, *next;
208
209 spin_lock_bh(&queue->lock);
210 list_for_each_entry_safe(entry, next, &queue->queue_list, list) {
211 if (!cmpfn || cmpfn(entry, data)) {
212 list_del(&entry->list);
213 queue->queue_total--;
214 nf_reinject(entry, NF_DROP);
215 }
216 }
217 spin_unlock_bh(&queue->lock);
218 }
219
220 static struct sk_buff *
221 nfqnl_build_packet_message(struct nfqnl_instance *queue,
222 struct nf_queue_entry *entry,
223 __be32 **packet_id_ptr)
224 {
225 sk_buff_data_t old_tail;
226 size_t size;
227 size_t data_len = 0, cap_len = 0;
228 struct sk_buff *skb;
229 struct nlattr *nla;
230 struct nfqnl_msg_packet_hdr *pmsg;
231 struct nlmsghdr *nlh;
232 struct nfgenmsg *nfmsg;
233 struct sk_buff *entskb = entry->skb;
234 struct net_device *indev;
235 struct net_device *outdev;
236 struct nf_conn *ct = NULL;
237 enum ip_conntrack_info uninitialized_var(ctinfo);
238
239 size = NLMSG_SPACE(sizeof(struct nfgenmsg))
240 + nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))
241 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
242 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
243 #ifdef CONFIG_BRIDGE_NETFILTER
244 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
245 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
246 #endif
247 + nla_total_size(sizeof(u_int32_t)) /* mark */
248 + nla_total_size(sizeof(struct nfqnl_msg_packet_hw))
249 + nla_total_size(sizeof(struct nfqnl_msg_packet_timestamp)
250 + nla_total_size(sizeof(u_int32_t))); /* cap_len */
251
252 outdev = entry->outdev;
253
254 switch ((enum nfqnl_config_mode)ACCESS_ONCE(queue->copy_mode)) {
255 case NFQNL_COPY_META:
256 case NFQNL_COPY_NONE:
257 break;
258
259 case NFQNL_COPY_PACKET:
260 if (entskb->ip_summed == CHECKSUM_PARTIAL &&
261 skb_checksum_help(entskb))
262 return NULL;
263
264 data_len = ACCESS_ONCE(queue->copy_range);
265 if (data_len == 0 || data_len > entskb->len)
266 data_len = entskb->len;
267
268 size += nla_total_size(data_len);
269 cap_len = entskb->len;
270 break;
271 }
272
273 if (queue->flags & NFQA_CFG_F_CONNTRACK)
274 ct = nfqnl_ct_get(entskb, &size, &ctinfo);
275
276 skb = alloc_skb(size, GFP_ATOMIC);
277 if (!skb)
278 return NULL;
279
280 old_tail = skb->tail;
281 nlh = nlmsg_put(skb, 0, 0,
282 NFNL_SUBSYS_QUEUE << 8 | NFQNL_MSG_PACKET,
283 sizeof(struct nfgenmsg), 0);
284 if (!nlh) {
285 kfree_skb(skb);
286 return NULL;
287 }
288 nfmsg = nlmsg_data(nlh);
289 nfmsg->nfgen_family = entry->pf;
290 nfmsg->version = NFNETLINK_V0;
291 nfmsg->res_id = htons(queue->queue_num);
292
293 nla = __nla_reserve(skb, NFQA_PACKET_HDR, sizeof(*pmsg));
294 pmsg = nla_data(nla);
295 pmsg->hw_protocol = entskb->protocol;
296 pmsg->hook = entry->hook;
297 *packet_id_ptr = &pmsg->packet_id;
298
299 indev = entry->indev;
300 if (indev) {
301 #ifndef CONFIG_BRIDGE_NETFILTER
302 if (nla_put_be32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex)))
303 goto nla_put_failure;
304 #else
305 if (entry->pf == PF_BRIDGE) {
306 /* Case 1: indev is physical input device, we need to
307 * look for bridge group (when called from
308 * netfilter_bridge) */
309 if (nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
310 htonl(indev->ifindex)) ||
311 /* this is the bridge group "brX" */
312 /* rcu_read_lock()ed by __nf_queue */
313 nla_put_be32(skb, NFQA_IFINDEX_INDEV,
314 htonl(br_port_get_rcu(indev)->br->dev->ifindex)))
315 goto nla_put_failure;
316 } else {
317 /* Case 2: indev is bridge group, we need to look for
318 * physical device (when called from ipv4) */
319 if (nla_put_be32(skb, NFQA_IFINDEX_INDEV,
320 htonl(indev->ifindex)))
321 goto nla_put_failure;
322 if (entskb->nf_bridge && entskb->nf_bridge->physindev &&
323 nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
324 htonl(entskb->nf_bridge->physindev->ifindex)))
325 goto nla_put_failure;
326 }
327 #endif
328 }
329
330 if (outdev) {
331 #ifndef CONFIG_BRIDGE_NETFILTER
332 if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex)))
333 goto nla_put_failure;
334 #else
335 if (entry->pf == PF_BRIDGE) {
336 /* Case 1: outdev is physical output device, we need to
337 * look for bridge group (when called from
338 * netfilter_bridge) */
339 if (nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
340 htonl(outdev->ifindex)) ||
341 /* this is the bridge group "brX" */
342 /* rcu_read_lock()ed by __nf_queue */
343 nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
344 htonl(br_port_get_rcu(outdev)->br->dev->ifindex)))
345 goto nla_put_failure;
346 } else {
347 /* Case 2: outdev is bridge group, we need to look for
348 * physical output device (when called from ipv4) */
349 if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
350 htonl(outdev->ifindex)))
351 goto nla_put_failure;
352 if (entskb->nf_bridge && entskb->nf_bridge->physoutdev &&
353 nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
354 htonl(entskb->nf_bridge->physoutdev->ifindex)))
355 goto nla_put_failure;
356 }
357 #endif
358 }
359
360 if (entskb->mark &&
361 nla_put_be32(skb, NFQA_MARK, htonl(entskb->mark)))
362 goto nla_put_failure;
363
364 if (indev && entskb->dev &&
365 entskb->mac_header != entskb->network_header) {
366 struct nfqnl_msg_packet_hw phw;
367 int len = dev_parse_header(entskb, phw.hw_addr);
368 if (len) {
369 phw.hw_addrlen = htons(len);
370 if (nla_put(skb, NFQA_HWADDR, sizeof(phw), &phw))
371 goto nla_put_failure;
372 }
373 }
374
375 if (entskb->tstamp.tv64) {
376 struct nfqnl_msg_packet_timestamp ts;
377 struct timeval tv = ktime_to_timeval(entskb->tstamp);
378 ts.sec = cpu_to_be64(tv.tv_sec);
379 ts.usec = cpu_to_be64(tv.tv_usec);
380
381 if (nla_put(skb, NFQA_TIMESTAMP, sizeof(ts), &ts))
382 goto nla_put_failure;
383 }
384
385 if (data_len) {
386 struct nlattr *nla;
387 int sz = nla_attr_size(data_len);
388
389 if (skb_tailroom(skb) < nla_total_size(data_len)) {
390 printk(KERN_WARNING "nf_queue: no tailroom!\n");
391 kfree_skb(skb);
392 return NULL;
393 }
394
395 nla = (struct nlattr *)skb_put(skb, nla_total_size(data_len));
396 nla->nla_type = NFQA_PAYLOAD;
397 nla->nla_len = sz;
398
399 if (skb_copy_bits(entskb, 0, nla_data(nla), data_len))
400 BUG();
401 }
402
403 if (ct && nfqnl_ct_put(skb, ct, ctinfo) < 0)
404 goto nla_put_failure;
405
406 if (cap_len > 0 && nla_put_be32(skb, NFQA_CAP_LEN, htonl(cap_len)))
407 goto nla_put_failure;
408
409 nlh->nlmsg_len = skb->tail - old_tail;
410 return skb;
411
412 nla_put_failure:
413 kfree_skb(skb);
414 net_err_ratelimited("nf_queue: error creating packet message\n");
415 return NULL;
416 }
417
418 static int
419 nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
420 {
421 struct sk_buff *nskb;
422 struct nfqnl_instance *queue;
423 int err = -ENOBUFS;
424 __be32 *packet_id_ptr;
425 int failopen = 0;
426
427 /* rcu_read_lock()ed by nf_hook_slow() */
428 queue = instance_lookup(queuenum);
429 if (!queue) {
430 err = -ESRCH;
431 goto err_out;
432 }
433
434 if (queue->copy_mode == NFQNL_COPY_NONE) {
435 err = -EINVAL;
436 goto err_out;
437 }
438
439 nskb = nfqnl_build_packet_message(queue, entry, &packet_id_ptr);
440 if (nskb == NULL) {
441 err = -ENOMEM;
442 goto err_out;
443 }
444 spin_lock_bh(&queue->lock);
445
446 if (!queue->peer_portid) {
447 err = -EINVAL;
448 goto err_out_free_nskb;
449 }
450 if (queue->queue_total >= queue->queue_maxlen) {
451 if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
452 failopen = 1;
453 err = 0;
454 } else {
455 queue->queue_dropped++;
456 net_warn_ratelimited("nf_queue: full at %d entries, dropping packets(s)\n",
457 queue->queue_total);
458 }
459 goto err_out_free_nskb;
460 }
461 entry->id = ++queue->id_sequence;
462 *packet_id_ptr = htonl(entry->id);
463
464 /* nfnetlink_unicast will either free the nskb or add it to a socket */
465 err = nfnetlink_unicast(nskb, &init_net, queue->peer_portid, MSG_DONTWAIT);
466 if (err < 0) {
467 queue->queue_user_dropped++;
468 goto err_out_unlock;
469 }
470
471 __enqueue_entry(queue, entry);
472
473 spin_unlock_bh(&queue->lock);
474 return 0;
475
476 err_out_free_nskb:
477 kfree_skb(nskb);
478 err_out_unlock:
479 spin_unlock_bh(&queue->lock);
480 if (failopen)
481 nf_reinject(entry, NF_ACCEPT);
482 err_out:
483 return err;
484 }
485
486 static int
487 nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e, int diff)
488 {
489 struct sk_buff *nskb;
490
491 if (diff < 0) {
492 if (pskb_trim(e->skb, data_len))
493 return -ENOMEM;
494 } else if (diff > 0) {
495 if (data_len > 0xFFFF)
496 return -EINVAL;
497 if (diff > skb_tailroom(e->skb)) {
498 nskb = skb_copy_expand(e->skb, skb_headroom(e->skb),
499 diff, GFP_ATOMIC);
500 if (!nskb) {
501 printk(KERN_WARNING "nf_queue: OOM "
502 "in mangle, dropping packet\n");
503 return -ENOMEM;
504 }
505 kfree_skb(e->skb);
506 e->skb = nskb;
507 }
508 skb_put(e->skb, diff);
509 }
510 if (!skb_make_writable(e->skb, data_len))
511 return -ENOMEM;
512 skb_copy_to_linear_data(e->skb, data, data_len);
513 e->skb->ip_summed = CHECKSUM_NONE;
514 return 0;
515 }
516
517 static int
518 nfqnl_set_mode(struct nfqnl_instance *queue,
519 unsigned char mode, unsigned int range)
520 {
521 int status = 0;
522
523 spin_lock_bh(&queue->lock);
524 switch (mode) {
525 case NFQNL_COPY_NONE:
526 case NFQNL_COPY_META:
527 queue->copy_mode = mode;
528 queue->copy_range = 0;
529 break;
530
531 case NFQNL_COPY_PACKET:
532 queue->copy_mode = mode;
533 /* We're using struct nlattr which has 16bit nla_len. Note that
534 * nla_len includes the header length. Thus, the maximum packet
535 * length that we support is 65531 bytes. We send truncated
536 * packets if the specified length is larger than that.
537 */
538 if (range > 0xffff - NLA_HDRLEN)
539 queue->copy_range = 0xffff - NLA_HDRLEN;
540 else
541 queue->copy_range = range;
542 break;
543
544 default:
545 status = -EINVAL;
546
547 }
548 spin_unlock_bh(&queue->lock);
549
550 return status;
551 }
552
553 static int
554 dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex)
555 {
556 if (entry->indev)
557 if (entry->indev->ifindex == ifindex)
558 return 1;
559 if (entry->outdev)
560 if (entry->outdev->ifindex == ifindex)
561 return 1;
562 #ifdef CONFIG_BRIDGE_NETFILTER
563 if (entry->skb->nf_bridge) {
564 if (entry->skb->nf_bridge->physindev &&
565 entry->skb->nf_bridge->physindev->ifindex == ifindex)
566 return 1;
567 if (entry->skb->nf_bridge->physoutdev &&
568 entry->skb->nf_bridge->physoutdev->ifindex == ifindex)
569 return 1;
570 }
571 #endif
572 return 0;
573 }
574
575 /* drop all packets with either indev or outdev == ifindex from all queue
576 * instances */
577 static void
578 nfqnl_dev_drop(int ifindex)
579 {
580 int i;
581
582 rcu_read_lock();
583
584 for (i = 0; i < INSTANCE_BUCKETS; i++) {
585 struct nfqnl_instance *inst;
586 struct hlist_head *head = &instance_table[i];
587
588 hlist_for_each_entry_rcu(inst, head, hlist)
589 nfqnl_flush(inst, dev_cmp, ifindex);
590 }
591
592 rcu_read_unlock();
593 }
594
595 #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
596
597 static int
598 nfqnl_rcv_dev_event(struct notifier_block *this,
599 unsigned long event, void *ptr)
600 {
601 struct net_device *dev = ptr;
602
603 if (!net_eq(dev_net(dev), &init_net))
604 return NOTIFY_DONE;
605
606 /* Drop any packets associated with the downed device */
607 if (event == NETDEV_DOWN)
608 nfqnl_dev_drop(dev->ifindex);
609 return NOTIFY_DONE;
610 }
611
612 static struct notifier_block nfqnl_dev_notifier = {
613 .notifier_call = nfqnl_rcv_dev_event,
614 };
615
616 static int
617 nfqnl_rcv_nl_event(struct notifier_block *this,
618 unsigned long event, void *ptr)
619 {
620 struct netlink_notify *n = ptr;
621
622 if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
623 int i;
624
625 /* destroy all instances for this portid */
626 spin_lock(&instances_lock);
627 for (i = 0; i < INSTANCE_BUCKETS; i++) {
628 struct hlist_node *t2;
629 struct nfqnl_instance *inst;
630 struct hlist_head *head = &instance_table[i];
631
632 hlist_for_each_entry_safe(inst, t2, head, hlist) {
633 if ((n->net == &init_net) &&
634 (n->portid == inst->peer_portid))
635 __instance_destroy(inst);
636 }
637 }
638 spin_unlock(&instances_lock);
639 }
640 return NOTIFY_DONE;
641 }
642
643 static struct notifier_block nfqnl_rtnl_notifier = {
644 .notifier_call = nfqnl_rcv_nl_event,
645 };
646
647 static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = {
648 [NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
649 [NFQA_MARK] = { .type = NLA_U32 },
650 [NFQA_PAYLOAD] = { .type = NLA_UNSPEC },
651 [NFQA_CT] = { .type = NLA_UNSPEC },
652 };
653
654 static const struct nla_policy nfqa_verdict_batch_policy[NFQA_MAX+1] = {
655 [NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
656 [NFQA_MARK] = { .type = NLA_U32 },
657 };
658
659 static struct nfqnl_instance *verdict_instance_lookup(u16 queue_num, int nlportid)
660 {
661 struct nfqnl_instance *queue;
662
663 queue = instance_lookup(queue_num);
664 if (!queue)
665 return ERR_PTR(-ENODEV);
666
667 if (queue->peer_portid != nlportid)
668 return ERR_PTR(-EPERM);
669
670 return queue;
671 }
672
673 static struct nfqnl_msg_verdict_hdr*
674 verdicthdr_get(const struct nlattr * const nfqa[])
675 {
676 struct nfqnl_msg_verdict_hdr *vhdr;
677 unsigned int verdict;
678
679 if (!nfqa[NFQA_VERDICT_HDR])
680 return NULL;
681
682 vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]);
683 verdict = ntohl(vhdr->verdict) & NF_VERDICT_MASK;
684 if (verdict > NF_MAX_VERDICT || verdict == NF_STOLEN)
685 return NULL;
686 return vhdr;
687 }
688
689 static int nfq_id_after(unsigned int id, unsigned int max)
690 {
691 return (int)(id - max) > 0;
692 }
693
694 static int
695 nfqnl_recv_verdict_batch(struct sock *ctnl, struct sk_buff *skb,
696 const struct nlmsghdr *nlh,
697 const struct nlattr * const nfqa[])
698 {
699 struct nfgenmsg *nfmsg = nlmsg_data(nlh);
700 struct nf_queue_entry *entry, *tmp;
701 unsigned int verdict, maxid;
702 struct nfqnl_msg_verdict_hdr *vhdr;
703 struct nfqnl_instance *queue;
704 LIST_HEAD(batch_list);
705 u16 queue_num = ntohs(nfmsg->res_id);
706
707 queue = verdict_instance_lookup(queue_num, NETLINK_CB(skb).portid);
708 if (IS_ERR(queue))
709 return PTR_ERR(queue);
710
711 vhdr = verdicthdr_get(nfqa);
712 if (!vhdr)
713 return -EINVAL;
714
715 verdict = ntohl(vhdr->verdict);
716 maxid = ntohl(vhdr->id);
717
718 spin_lock_bh(&queue->lock);
719
720 list_for_each_entry_safe(entry, tmp, &queue->queue_list, list) {
721 if (nfq_id_after(entry->id, maxid))
722 break;
723 __dequeue_entry(queue, entry);
724 list_add_tail(&entry->list, &batch_list);
725 }
726
727 spin_unlock_bh(&queue->lock);
728
729 if (list_empty(&batch_list))
730 return -ENOENT;
731
732 list_for_each_entry_safe(entry, tmp, &batch_list, list) {
733 if (nfqa[NFQA_MARK])
734 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
735 nf_reinject(entry, verdict);
736 }
737 return 0;
738 }
739
740 static int
741 nfqnl_recv_verdict(struct sock *ctnl, struct sk_buff *skb,
742 const struct nlmsghdr *nlh,
743 const struct nlattr * const nfqa[])
744 {
745 struct nfgenmsg *nfmsg = nlmsg_data(nlh);
746 u_int16_t queue_num = ntohs(nfmsg->res_id);
747
748 struct nfqnl_msg_verdict_hdr *vhdr;
749 struct nfqnl_instance *queue;
750 unsigned int verdict;
751 struct nf_queue_entry *entry;
752 enum ip_conntrack_info uninitialized_var(ctinfo);
753 struct nf_conn *ct = NULL;
754
755 queue = instance_lookup(queue_num);
756 if (!queue)
757
758 queue = verdict_instance_lookup(queue_num, NETLINK_CB(skb).portid);
759 if (IS_ERR(queue))
760 return PTR_ERR(queue);
761
762 vhdr = verdicthdr_get(nfqa);
763 if (!vhdr)
764 return -EINVAL;
765
766 verdict = ntohl(vhdr->verdict);
767
768 entry = find_dequeue_entry(queue, ntohl(vhdr->id));
769 if (entry == NULL)
770 return -ENOENT;
771
772 rcu_read_lock();
773 if (nfqa[NFQA_CT] && (queue->flags & NFQA_CFG_F_CONNTRACK))
774 ct = nfqnl_ct_parse(entry->skb, nfqa[NFQA_CT], &ctinfo);
775
776 if (nfqa[NFQA_PAYLOAD]) {
777 u16 payload_len = nla_len(nfqa[NFQA_PAYLOAD]);
778 int diff = payload_len - entry->skb->len;
779
780 if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),
781 payload_len, entry, diff) < 0)
782 verdict = NF_DROP;
783
784 if (ct)
785 nfqnl_ct_seq_adjust(skb, ct, ctinfo, diff);
786 }
787 rcu_read_unlock();
788
789 if (nfqa[NFQA_MARK])
790 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
791
792 nf_reinject(entry, verdict);
793 return 0;
794 }
795
796 static int
797 nfqnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb,
798 const struct nlmsghdr *nlh,
799 const struct nlattr * const nfqa[])
800 {
801 return -ENOTSUPP;
802 }
803
804 static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = {
805 [NFQA_CFG_CMD] = { .len = sizeof(struct nfqnl_msg_config_cmd) },
806 [NFQA_CFG_PARAMS] = { .len = sizeof(struct nfqnl_msg_config_params) },
807 };
808
809 static const struct nf_queue_handler nfqh = {
810 .outfn = &nfqnl_enqueue_packet,
811 };
812
813 static int
814 nfqnl_recv_config(struct sock *ctnl, struct sk_buff *skb,
815 const struct nlmsghdr *nlh,
816 const struct nlattr * const nfqa[])
817 {
818 struct nfgenmsg *nfmsg = nlmsg_data(nlh);
819 u_int16_t queue_num = ntohs(nfmsg->res_id);
820 struct nfqnl_instance *queue;
821 struct nfqnl_msg_config_cmd *cmd = NULL;
822 int ret = 0;
823
824 if (nfqa[NFQA_CFG_CMD]) {
825 cmd = nla_data(nfqa[NFQA_CFG_CMD]);
826
827 /* Obsolete commands without queue context */
828 switch (cmd->command) {
829 case NFQNL_CFG_CMD_PF_BIND: return 0;
830 case NFQNL_CFG_CMD_PF_UNBIND: return 0;
831 }
832 }
833
834 rcu_read_lock();
835 queue = instance_lookup(queue_num);
836 if (queue && queue->peer_portid != NETLINK_CB(skb).portid) {
837 ret = -EPERM;
838 goto err_out_unlock;
839 }
840
841 if (cmd != NULL) {
842 switch (cmd->command) {
843 case NFQNL_CFG_CMD_BIND:
844 if (queue) {
845 ret = -EBUSY;
846 goto err_out_unlock;
847 }
848 queue = instance_create(queue_num, NETLINK_CB(skb).portid);
849 if (IS_ERR(queue)) {
850 ret = PTR_ERR(queue);
851 goto err_out_unlock;
852 }
853 break;
854 case NFQNL_CFG_CMD_UNBIND:
855 if (!queue) {
856 ret = -ENODEV;
857 goto err_out_unlock;
858 }
859 instance_destroy(queue);
860 break;
861 case NFQNL_CFG_CMD_PF_BIND:
862 case NFQNL_CFG_CMD_PF_UNBIND:
863 break;
864 default:
865 ret = -ENOTSUPP;
866 break;
867 }
868 }
869
870 if (nfqa[NFQA_CFG_PARAMS]) {
871 struct nfqnl_msg_config_params *params;
872
873 if (!queue) {
874 ret = -ENODEV;
875 goto err_out_unlock;
876 }
877 params = nla_data(nfqa[NFQA_CFG_PARAMS]);
878 nfqnl_set_mode(queue, params->copy_mode,
879 ntohl(params->copy_range));
880 }
881
882 if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) {
883 __be32 *queue_maxlen;
884
885 if (!queue) {
886 ret = -ENODEV;
887 goto err_out_unlock;
888 }
889 queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]);
890 spin_lock_bh(&queue->lock);
891 queue->queue_maxlen = ntohl(*queue_maxlen);
892 spin_unlock_bh(&queue->lock);
893 }
894
895 if (nfqa[NFQA_CFG_FLAGS]) {
896 __u32 flags, mask;
897
898 if (!queue) {
899 ret = -ENODEV;
900 goto err_out_unlock;
901 }
902
903 if (!nfqa[NFQA_CFG_MASK]) {
904 /* A mask is needed to specify which flags are being
905 * changed.
906 */
907 ret = -EINVAL;
908 goto err_out_unlock;
909 }
910
911 flags = ntohl(nla_get_be32(nfqa[NFQA_CFG_FLAGS]));
912 mask = ntohl(nla_get_be32(nfqa[NFQA_CFG_MASK]));
913
914 if (flags >= NFQA_CFG_F_MAX) {
915 ret = -EOPNOTSUPP;
916 goto err_out_unlock;
917 }
918
919 spin_lock_bh(&queue->lock);
920 queue->flags &= ~mask;
921 queue->flags |= flags & mask;
922 spin_unlock_bh(&queue->lock);
923 }
924
925 err_out_unlock:
926 rcu_read_unlock();
927 return ret;
928 }
929
930 static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
931 [NFQNL_MSG_PACKET] = { .call_rcu = nfqnl_recv_unsupp,
932 .attr_count = NFQA_MAX, },
933 [NFQNL_MSG_VERDICT] = { .call_rcu = nfqnl_recv_verdict,
934 .attr_count = NFQA_MAX,
935 .policy = nfqa_verdict_policy },
936 [NFQNL_MSG_CONFIG] = { .call = nfqnl_recv_config,
937 .attr_count = NFQA_CFG_MAX,
938 .policy = nfqa_cfg_policy },
939 [NFQNL_MSG_VERDICT_BATCH]={ .call_rcu = nfqnl_recv_verdict_batch,
940 .attr_count = NFQA_MAX,
941 .policy = nfqa_verdict_batch_policy },
942 };
943
944 static const struct nfnetlink_subsystem nfqnl_subsys = {
945 .name = "nf_queue",
946 .subsys_id = NFNL_SUBSYS_QUEUE,
947 .cb_count = NFQNL_MSG_MAX,
948 .cb = nfqnl_cb,
949 };
950
951 #ifdef CONFIG_PROC_FS
952 struct iter_state {
953 unsigned int bucket;
954 };
955
956 static struct hlist_node *get_first(struct seq_file *seq)
957 {
958 struct iter_state *st = seq->private;
959
960 if (!st)
961 return NULL;
962
963 for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
964 if (!hlist_empty(&instance_table[st->bucket]))
965 return instance_table[st->bucket].first;
966 }
967 return NULL;
968 }
969
970 static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h)
971 {
972 struct iter_state *st = seq->private;
973
974 h = h->next;
975 while (!h) {
976 if (++st->bucket >= INSTANCE_BUCKETS)
977 return NULL;
978
979 h = instance_table[st->bucket].first;
980 }
981 return h;
982 }
983
984 static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos)
985 {
986 struct hlist_node *head;
987 head = get_first(seq);
988
989 if (head)
990 while (pos && (head = get_next(seq, head)))
991 pos--;
992 return pos ? NULL : head;
993 }
994
995 static void *seq_start(struct seq_file *seq, loff_t *pos)
996 __acquires(instances_lock)
997 {
998 spin_lock(&instances_lock);
999 return get_idx(seq, *pos);
1000 }
1001
1002 static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
1003 {
1004 (*pos)++;
1005 return get_next(s, v);
1006 }
1007
1008 static void seq_stop(struct seq_file *s, void *v)
1009 __releases(instances_lock)
1010 {
1011 spin_unlock(&instances_lock);
1012 }
1013
1014 static int seq_show(struct seq_file *s, void *v)
1015 {
1016 const struct nfqnl_instance *inst = v;
1017
1018 return seq_printf(s, "%5d %6d %5d %1d %5d %5d %5d %8d %2d\n",
1019 inst->queue_num,
1020 inst->peer_portid, inst->queue_total,
1021 inst->copy_mode, inst->copy_range,
1022 inst->queue_dropped, inst->queue_user_dropped,
1023 inst->id_sequence, 1);
1024 }
1025
1026 static const struct seq_operations nfqnl_seq_ops = {
1027 .start = seq_start,
1028 .next = seq_next,
1029 .stop = seq_stop,
1030 .show = seq_show,
1031 };
1032
1033 static int nfqnl_open(struct inode *inode, struct file *file)
1034 {
1035 return seq_open_private(file, &nfqnl_seq_ops,
1036 sizeof(struct iter_state));
1037 }
1038
1039 static const struct file_operations nfqnl_file_ops = {
1040 .owner = THIS_MODULE,
1041 .open = nfqnl_open,
1042 .read = seq_read,
1043 .llseek = seq_lseek,
1044 .release = seq_release_private,
1045 };
1046
1047 #endif /* PROC_FS */
1048
1049 static int __init nfnetlink_queue_init(void)
1050 {
1051 int i, status = -ENOMEM;
1052
1053 for (i = 0; i < INSTANCE_BUCKETS; i++)
1054 INIT_HLIST_HEAD(&instance_table[i]);
1055
1056 netlink_register_notifier(&nfqnl_rtnl_notifier);
1057 status = nfnetlink_subsys_register(&nfqnl_subsys);
1058 if (status < 0) {
1059 printk(KERN_ERR "nf_queue: failed to create netlink socket\n");
1060 goto cleanup_netlink_notifier;
1061 }
1062
1063 #ifdef CONFIG_PROC_FS
1064 if (!proc_create("nfnetlink_queue", 0440,
1065 proc_net_netfilter, &nfqnl_file_ops)) {
1066 status = -ENOMEM;
1067 goto cleanup_subsys;
1068 }
1069 #endif
1070
1071 register_netdevice_notifier(&nfqnl_dev_notifier);
1072 nf_register_queue_handler(&nfqh);
1073 return status;
1074
1075 #ifdef CONFIG_PROC_FS
1076 cleanup_subsys:
1077 nfnetlink_subsys_unregister(&nfqnl_subsys);
1078 #endif
1079 cleanup_netlink_notifier:
1080 netlink_unregister_notifier(&nfqnl_rtnl_notifier);
1081 return status;
1082 }
1083
1084 static void __exit nfnetlink_queue_fini(void)
1085 {
1086 nf_unregister_queue_handler();
1087 unregister_netdevice_notifier(&nfqnl_dev_notifier);
1088 #ifdef CONFIG_PROC_FS
1089 remove_proc_entry("nfnetlink_queue", proc_net_netfilter);
1090 #endif
1091 nfnetlink_subsys_unregister(&nfqnl_subsys);
1092 netlink_unregister_notifier(&nfqnl_rtnl_notifier);
1093
1094 rcu_barrier(); /* Wait for completion of call_rcu()'s */
1095 }
1096
1097 MODULE_DESCRIPTION("netfilter packet queue handler");
1098 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
1099 MODULE_LICENSE("GPL");
1100 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE);
1101
1102 module_init(nfnetlink_queue_init);
1103 module_exit(nfnetlink_queue_fini);
Linux kernel - Deliverables
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