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viafb: Do not remove gpiochip under spinlock
[linux/fpc-iii.git] / net / netfilter / nfnetlink_log.c
blobd9b8fb8ab340b5a97e57073abdfe611f7b0c1c74
1 /*
2 * This is a module which is used for logging packets to userspace via
3 * nfetlink.
4 *
5 * (C) 2005 by Harald Welte <laforge@netfilter.org>
6 *
7 * Based on the old ipv4-only ipt_ULOG.c:
8 * (C) 2000-2004 by Harald Welte <laforge@netfilter.org>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 */
14 #include <linux/module.h>
15 #include <linux/skbuff.h>
16 #include <linux/init.h>
17 #include <linux/ip.h>
18 #include <linux/ipv6.h>
19 #include <linux/netdevice.h>
20 #include <linux/netfilter.h>
21 #include <linux/netlink.h>
22 #include <linux/netfilter/nfnetlink.h>
23 #include <linux/netfilter/nfnetlink_log.h>
24 #include <linux/spinlock.h>
25 #include <linux/sysctl.h>
26 #include <linux/proc_fs.h>
27 #include <linux/security.h>
28 #include <linux/list.h>
29 #include <linux/jhash.h>
30 #include <linux/random.h>
31 #include <net/sock.h>
32 #include <net/netfilter/nf_log.h>
33 #include <net/netfilter/nfnetlink_log.h>
34
35 #include <asm/atomic.h>
36
37 #ifdef CONFIG_BRIDGE_NETFILTER
38 #include "../bridge/br_private.h"
39 #endif
40
41 #define NFULNL_NLBUFSIZ_DEFAULT NLMSG_GOODSIZE
42 #define NFULNL_TIMEOUT_DEFAULT 100 /* every second */
43 #define NFULNL_QTHRESH_DEFAULT 100 /* 100 packets */
44 #define NFULNL_COPY_RANGE_MAX 0xFFFF /* max packet size is limited by 16-bit struct nfattr nfa_len field */
45
46 #define PRINTR(x, args...) do { if (net_ratelimit()) \
47 printk(x, ## args); } while (0);
48
49 struct nfulnl_instance {
50 struct hlist_node hlist; /* global list of instances */
51 spinlock_t lock;
52 atomic_t use; /* use count */
53
54 unsigned int qlen; /* number of nlmsgs in skb */
55 struct sk_buff *skb; /* pre-allocatd skb */
56 struct timer_list timer;
57 int peer_pid; /* PID of the peer process */
58
59 /* configurable parameters */
60 unsigned int flushtimeout; /* timeout until queue flush */
61 unsigned int nlbufsiz; /* netlink buffer allocation size */
62 unsigned int qthreshold; /* threshold of the queue */
63 u_int32_t copy_range;
64 u_int32_t seq; /* instance-local sequential counter */
65 u_int16_t group_num; /* number of this queue */
66 u_int16_t flags;
67 u_int8_t copy_mode;
68 };
69
70 static DEFINE_RWLOCK(instances_lock);
71 static atomic_t global_seq;
72
73 #define INSTANCE_BUCKETS 16
74 static struct hlist_head instance_table[INSTANCE_BUCKETS];
75 static unsigned int hash_init;
76
77 static inline u_int8_t instance_hashfn(u_int16_t group_num)
78 {
79 return ((group_num & 0xff) % INSTANCE_BUCKETS);
80 }
81
82 static struct nfulnl_instance *
83 __instance_lookup(u_int16_t group_num)
84 {
85 struct hlist_head *head;
86 struct hlist_node *pos;
87 struct nfulnl_instance *inst;
88
89 head = &instance_table[instance_hashfn(group_num)];
90 hlist_for_each_entry(inst, pos, head, hlist) {
91 if (inst->group_num == group_num)
92 return inst;
93 }
94 return NULL;
95 }
96
97 static inline void
98 instance_get(struct nfulnl_instance *inst)
99 {
100 atomic_inc(&inst->use);
101 }
102
103 static struct nfulnl_instance *
104 instance_lookup_get(u_int16_t group_num)
105 {
106 struct nfulnl_instance *inst;
107
108 read_lock_bh(&instances_lock);
109 inst = __instance_lookup(group_num);
110 if (inst)
111 instance_get(inst);
112 read_unlock_bh(&instances_lock);
113
114 return inst;
115 }
116
117 static void
118 instance_put(struct nfulnl_instance *inst)
119 {
120 if (inst && atomic_dec_and_test(&inst->use)) {
121 kfree(inst);
122 module_put(THIS_MODULE);
123 }
124 }
125
126 static void nfulnl_timer(unsigned long data);
127
128 static struct nfulnl_instance *
129 instance_create(u_int16_t group_num, int pid)
130 {
131 struct nfulnl_instance *inst;
132 int err;
133
134 write_lock_bh(&instances_lock);
135 if (__instance_lookup(group_num)) {
136 err = -EEXIST;
137 goto out_unlock;
138 }
139
140 inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
141 if (!inst) {
142 err = -ENOMEM;
143 goto out_unlock;
144 }
145
146 if (!try_module_get(THIS_MODULE)) {
147 kfree(inst);
148 err = -EAGAIN;
149 goto out_unlock;
150 }
151
152 INIT_HLIST_NODE(&inst->hlist);
153 spin_lock_init(&inst->lock);
154 /* needs to be two, since we _put() after creation */
155 atomic_set(&inst->use, 2);
156
157 setup_timer(&inst->timer, nfulnl_timer, (unsigned long)inst);
158
159 inst->peer_pid = pid;
160 inst->group_num = group_num;
161
162 inst->qthreshold = NFULNL_QTHRESH_DEFAULT;
163 inst->flushtimeout = NFULNL_TIMEOUT_DEFAULT;
164 inst->nlbufsiz = NFULNL_NLBUFSIZ_DEFAULT;
165 inst->copy_mode = NFULNL_COPY_PACKET;
166 inst->copy_range = NFULNL_COPY_RANGE_MAX;
167
168 hlist_add_head(&inst->hlist,
169 &instance_table[instance_hashfn(group_num)]);
170
171 write_unlock_bh(&instances_lock);
172
173 return inst;
174
175 out_unlock:
176 write_unlock_bh(&instances_lock);
177 return ERR_PTR(err);
178 }
179
180 static void __nfulnl_flush(struct nfulnl_instance *inst);
181
182 static void
183 __instance_destroy(struct nfulnl_instance *inst)
184 {
185 /* first pull it out of the global list */
186 hlist_del(&inst->hlist);
187
188 /* then flush all pending packets from skb */
189
190 spin_lock_bh(&inst->lock);
191 if (inst->skb)
192 __nfulnl_flush(inst);
193 spin_unlock_bh(&inst->lock);
194
195 /* and finally put the refcount */
196 instance_put(inst);
197 }
198
199 static inline void
200 instance_destroy(struct nfulnl_instance *inst)
201 {
202 write_lock_bh(&instances_lock);
203 __instance_destroy(inst);
204 write_unlock_bh(&instances_lock);
205 }
206
207 static int
208 nfulnl_set_mode(struct nfulnl_instance *inst, u_int8_t mode,
209 unsigned int range)
210 {
211 int status = 0;
212
213 spin_lock_bh(&inst->lock);
214
215 switch (mode) {
216 case NFULNL_COPY_NONE:
217 case NFULNL_COPY_META:
218 inst->copy_mode = mode;
219 inst->copy_range = 0;
220 break;
221
222 case NFULNL_COPY_PACKET:
223 inst->copy_mode = mode;
224 inst->copy_range = min_t(unsigned int,
225 range, NFULNL_COPY_RANGE_MAX);
226 break;
227
228 default:
229 status = -EINVAL;
230 break;
231 }
232
233 spin_unlock_bh(&inst->lock);
234
235 return status;
236 }
237
238 static int
239 nfulnl_set_nlbufsiz(struct nfulnl_instance *inst, u_int32_t nlbufsiz)
240 {
241 int status;
242
243 spin_lock_bh(&inst->lock);
244 if (nlbufsiz < NFULNL_NLBUFSIZ_DEFAULT)
245 status = -ERANGE;
246 else if (nlbufsiz > 131072)
247 status = -ERANGE;
248 else {
249 inst->nlbufsiz = nlbufsiz;
250 status = 0;
251 }
252 spin_unlock_bh(&inst->lock);
253
254 return status;
255 }
256
257 static int
258 nfulnl_set_timeout(struct nfulnl_instance *inst, u_int32_t timeout)
259 {
260 spin_lock_bh(&inst->lock);
261 inst->flushtimeout = timeout;
262 spin_unlock_bh(&inst->lock);
263
264 return 0;
265 }
266
267 static int
268 nfulnl_set_qthresh(struct nfulnl_instance *inst, u_int32_t qthresh)
269 {
270 spin_lock_bh(&inst->lock);
271 inst->qthreshold = qthresh;
272 spin_unlock_bh(&inst->lock);
273
274 return 0;
275 }
276
277 static int
278 nfulnl_set_flags(struct nfulnl_instance *inst, u_int16_t flags)
279 {
280 spin_lock_bh(&inst->lock);
281 inst->flags = flags;
282 spin_unlock_bh(&inst->lock);
283
284 return 0;
285 }
286
287 static struct sk_buff *
288 nfulnl_alloc_skb(unsigned int inst_size, unsigned int pkt_size)
289 {
290 struct sk_buff *skb;
291 unsigned int n;
292
293 /* alloc skb which should be big enough for a whole multipart
294 * message. WARNING: has to be <= 128k due to slab restrictions */
295
296 n = max(inst_size, pkt_size);
297 skb = alloc_skb(n, GFP_ATOMIC);
298 if (!skb) {
299 PRINTR("nfnetlink_log: can't alloc whole buffer (%u bytes)\n",
300 inst_size);
301
302 if (n > pkt_size) {
303 /* try to allocate only as much as we need for current
304 * packet */
305
306 skb = alloc_skb(pkt_size, GFP_ATOMIC);
307 if (!skb)
308 PRINTR("nfnetlink_log: can't even alloc %u "
309 "bytes\n", pkt_size);
310 }
311 }
312
313 return skb;
314 }
315
316 static int
317 __nfulnl_send(struct nfulnl_instance *inst)
318 {
319 int status = -1;
320
321 if (inst->qlen > 1)
322 NLMSG_PUT(inst->skb, 0, 0,
323 NLMSG_DONE,
324 sizeof(struct nfgenmsg));
325
326 status = nfnetlink_unicast(inst->skb, &init_net, inst->peer_pid,
327 MSG_DONTWAIT);
328
329 inst->qlen = 0;
330 inst->skb = NULL;
331
332 nlmsg_failure:
333 return status;
334 }
335
336 static void
337 __nfulnl_flush(struct nfulnl_instance *inst)
338 {
339 /* timer holds a reference */
340 if (del_timer(&inst->timer))
341 instance_put(inst);
342 if (inst->skb)
343 __nfulnl_send(inst);
344 }
345
346 static void
347 nfulnl_timer(unsigned long data)
348 {
349 struct nfulnl_instance *inst = (struct nfulnl_instance *)data;
350
351 spin_lock_bh(&inst->lock);
352 if (inst->skb)
353 __nfulnl_send(inst);
354 spin_unlock_bh(&inst->lock);
355 instance_put(inst);
356 }
357
358 /* This is an inline function, we don't really care about a long
359 * list of arguments */
360 static inline int
361 __build_packet_message(struct nfulnl_instance *inst,
362 const struct sk_buff *skb,
363 unsigned int data_len,
364 u_int8_t pf,
365 unsigned int hooknum,
366 const struct net_device *indev,
367 const struct net_device *outdev,
368 const struct nf_loginfo *li,
369 const char *prefix, unsigned int plen)
370 {
371 struct nfulnl_msg_packet_hdr pmsg;
372 struct nlmsghdr *nlh;
373 struct nfgenmsg *nfmsg;
374 __be32 tmp_uint;
375 sk_buff_data_t old_tail = inst->skb->tail;
376
377 nlh = NLMSG_PUT(inst->skb, 0, 0,
378 NFNL_SUBSYS_ULOG << 8 | NFULNL_MSG_PACKET,
379 sizeof(struct nfgenmsg));
380 nfmsg = NLMSG_DATA(nlh);
381 nfmsg->nfgen_family = pf;
382 nfmsg->version = NFNETLINK_V0;
383 nfmsg->res_id = htons(inst->group_num);
384
385 pmsg.hw_protocol = skb->protocol;
386 pmsg.hook = hooknum;
387
388 NLA_PUT(inst->skb, NFULA_PACKET_HDR, sizeof(pmsg), &pmsg);
389
390 if (prefix)
391 NLA_PUT(inst->skb, NFULA_PREFIX, plen, prefix);
392
393 if (indev) {
394 #ifndef CONFIG_BRIDGE_NETFILTER
395 NLA_PUT_BE32(inst->skb, NFULA_IFINDEX_INDEV,
396 htonl(indev->ifindex));
397 #else
398 if (pf == PF_BRIDGE) {
399 /* Case 1: outdev is physical input device, we need to
400 * look for bridge group (when called from
401 * netfilter_bridge) */
402 NLA_PUT_BE32(inst->skb, NFULA_IFINDEX_PHYSINDEV,
403 htonl(indev->ifindex));
404 /* this is the bridge group "brX" */
405 NLA_PUT_BE32(inst->skb, NFULA_IFINDEX_INDEV,
406 htonl(indev->br_port->br->dev->ifindex));
407 } else {
408 /* Case 2: indev is bridge group, we need to look for
409 * physical device (when called from ipv4) */
410 NLA_PUT_BE32(inst->skb, NFULA_IFINDEX_INDEV,
411 htonl(indev->ifindex));
412 if (skb->nf_bridge && skb->nf_bridge->physindev)
413 NLA_PUT_BE32(inst->skb, NFULA_IFINDEX_PHYSINDEV,
414 htonl(skb->nf_bridge->physindev->ifindex));
415 }
416 #endif
417 }
418
419 if (outdev) {
420 tmp_uint = htonl(outdev->ifindex);
421 #ifndef CONFIG_BRIDGE_NETFILTER
422 NLA_PUT_BE32(inst->skb, NFULA_IFINDEX_OUTDEV,
423 htonl(outdev->ifindex));
424 #else
425 if (pf == PF_BRIDGE) {
426 /* Case 1: outdev is physical output device, we need to
427 * look for bridge group (when called from
428 * netfilter_bridge) */
429 NLA_PUT_BE32(inst->skb, NFULA_IFINDEX_PHYSOUTDEV,
430 htonl(outdev->ifindex));
431 /* this is the bridge group "brX" */
432 NLA_PUT_BE32(inst->skb, NFULA_IFINDEX_OUTDEV,
433 htonl(outdev->br_port->br->dev->ifindex));
434 } else {
435 /* Case 2: indev is a bridge group, we need to look
436 * for physical device (when called from ipv4) */
437 NLA_PUT_BE32(inst->skb, NFULA_IFINDEX_OUTDEV,
438 htonl(outdev->ifindex));
439 if (skb->nf_bridge && skb->nf_bridge->physoutdev)
440 NLA_PUT_BE32(inst->skb, NFULA_IFINDEX_PHYSOUTDEV,
441 htonl(skb->nf_bridge->physoutdev->ifindex));
442 }
443 #endif
444 }
445
446 if (skb->mark)
447 NLA_PUT_BE32(inst->skb, NFULA_MARK, htonl(skb->mark));
448
449 if (indev && skb->dev) {
450 struct nfulnl_msg_packet_hw phw;
451 int len = dev_parse_header(skb, phw.hw_addr);
452 if (len > 0) {
453 phw.hw_addrlen = htons(len);
454 NLA_PUT(inst->skb, NFULA_HWADDR, sizeof(phw), &phw);
455 }
456 }
457
458 if (indev && skb_mac_header_was_set(skb)) {
459 NLA_PUT_BE16(inst->skb, NFULA_HWTYPE, htons(skb->dev->type));
460 NLA_PUT_BE16(inst->skb, NFULA_HWLEN,
461 htons(skb->dev->hard_header_len));
462 NLA_PUT(inst->skb, NFULA_HWHEADER, skb->dev->hard_header_len,
463 skb_mac_header(skb));
464 }
465
466 if (skb->tstamp.tv64) {
467 struct nfulnl_msg_packet_timestamp ts;
468 struct timeval tv = ktime_to_timeval(skb->tstamp);
469 ts.sec = cpu_to_be64(tv.tv_sec);
470 ts.usec = cpu_to_be64(tv.tv_usec);
471
472 NLA_PUT(inst->skb, NFULA_TIMESTAMP, sizeof(ts), &ts);
473 }
474
475 /* UID */
476 if (skb->sk) {
477 read_lock_bh(&skb->sk->sk_callback_lock);
478 if (skb->sk->sk_socket && skb->sk->sk_socket->file) {
479 struct file *file = skb->sk->sk_socket->file;
480 __be32 uid = htonl(file->f_cred->fsuid);
481 __be32 gid = htonl(file->f_cred->fsgid);
482 /* need to unlock here since NLA_PUT may goto */
483 read_unlock_bh(&skb->sk->sk_callback_lock);
484 NLA_PUT_BE32(inst->skb, NFULA_UID, uid);
485 NLA_PUT_BE32(inst->skb, NFULA_GID, gid);
486 } else
487 read_unlock_bh(&skb->sk->sk_callback_lock);
488 }
489
490 /* local sequence number */
491 if (inst->flags & NFULNL_CFG_F_SEQ)
492 NLA_PUT_BE32(inst->skb, NFULA_SEQ, htonl(inst->seq++));
493
494 /* global sequence number */
495 if (inst->flags & NFULNL_CFG_F_SEQ_GLOBAL)
496 NLA_PUT_BE32(inst->skb, NFULA_SEQ_GLOBAL,
497 htonl(atomic_inc_return(&global_seq)));
498
499 if (data_len) {
500 struct nlattr *nla;
501 int size = nla_attr_size(data_len);
502
503 if (skb_tailroom(inst->skb) < nla_total_size(data_len)) {
504 printk(KERN_WARNING "nfnetlink_log: no tailroom!\n");
505 goto nlmsg_failure;
506 }
507
508 nla = (struct nlattr *)skb_put(inst->skb, nla_total_size(data_len));
509 nla->nla_type = NFULA_PAYLOAD;
510 nla->nla_len = size;
511
512 if (skb_copy_bits(skb, 0, nla_data(nla), data_len))
513 BUG();
514 }
515
516 nlh->nlmsg_len = inst->skb->tail - old_tail;
517 return 0;
518
519 nlmsg_failure:
520 nla_put_failure:
521 PRINTR(KERN_ERR "nfnetlink_log: error creating log nlmsg\n");
522 return -1;
523 }
524
525 #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
526
527 static struct nf_loginfo default_loginfo = {
528 .type = NF_LOG_TYPE_ULOG,
529 .u = {
530 .ulog = {
531 .copy_len = 0xffff,
532 .group = 0,
533 .qthreshold = 1,
534 },
535 },
536 };
537
538 /* log handler for internal netfilter logging api */
539 void
540 nfulnl_log_packet(u_int8_t pf,
541 unsigned int hooknum,
542 const struct sk_buff *skb,
543 const struct net_device *in,
544 const struct net_device *out,
545 const struct nf_loginfo *li_user,
546 const char *prefix)
547 {
548 unsigned int size, data_len;
549 struct nfulnl_instance *inst;
550 const struct nf_loginfo *li;
551 unsigned int qthreshold;
552 unsigned int plen;
553
554 if (li_user && li_user->type == NF_LOG_TYPE_ULOG)
555 li = li_user;
556 else
557 li = &default_loginfo;
558
559 inst = instance_lookup_get(li->u.ulog.group);
560 if (!inst)
561 return;
562
563 plen = 0;
564 if (prefix)
565 plen = strlen(prefix) + 1;
566
567 /* FIXME: do we want to make the size calculation conditional based on
568 * what is actually present? way more branches and checks, but more
569 * memory efficient... */
570 size = NLMSG_SPACE(sizeof(struct nfgenmsg))
571 + nla_total_size(sizeof(struct nfulnl_msg_packet_hdr))
572 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
573 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
574 #ifdef CONFIG_BRIDGE_NETFILTER
575 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
576 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
577 #endif
578 + nla_total_size(sizeof(u_int32_t)) /* mark */
579 + nla_total_size(sizeof(u_int32_t)) /* uid */
580 + nla_total_size(sizeof(u_int32_t)) /* gid */
581 + nla_total_size(plen) /* prefix */
582 + nla_total_size(sizeof(struct nfulnl_msg_packet_hw))
583 + nla_total_size(sizeof(struct nfulnl_msg_packet_timestamp));
584
585 if (in && skb_mac_header_was_set(skb)) {
586 size += nla_total_size(skb->dev->hard_header_len)
587 + nla_total_size(sizeof(u_int16_t)) /* hwtype */
588 + nla_total_size(sizeof(u_int16_t)); /* hwlen */
589 }
590
591 spin_lock_bh(&inst->lock);
592
593 if (inst->flags & NFULNL_CFG_F_SEQ)
594 size += nla_total_size(sizeof(u_int32_t));
595 if (inst->flags & NFULNL_CFG_F_SEQ_GLOBAL)
596 size += nla_total_size(sizeof(u_int32_t));
597
598 qthreshold = inst->qthreshold;
599 /* per-rule qthreshold overrides per-instance */
600 if (li->u.ulog.qthreshold)
601 if (qthreshold > li->u.ulog.qthreshold)
602 qthreshold = li->u.ulog.qthreshold;
603
604
605 switch (inst->copy_mode) {
606 case NFULNL_COPY_META:
607 case NFULNL_COPY_NONE:
608 data_len = 0;
609 break;
610
611 case NFULNL_COPY_PACKET:
612 if (inst->copy_range == 0
613 || inst->copy_range > skb->len)
614 data_len = skb->len;
615 else
616 data_len = inst->copy_range;
617
618 size += nla_total_size(data_len);
619 break;
620
621 default:
622 goto unlock_and_release;
623 }
624
625 if (inst->skb &&
626 size > skb_tailroom(inst->skb) - sizeof(struct nfgenmsg)) {
627 /* either the queue len is too high or we don't have
628 * enough room in the skb left. flush to userspace. */
629 __nfulnl_flush(inst);
630 }
631
632 if (!inst->skb) {
633 inst->skb = nfulnl_alloc_skb(inst->nlbufsiz, size);
634 if (!inst->skb)
635 goto alloc_failure;
636 }
637
638 inst->qlen++;
639
640 __build_packet_message(inst, skb, data_len, pf,
641 hooknum, in, out, li, prefix, plen);
642
643 if (inst->qlen >= qthreshold)
644 __nfulnl_flush(inst);
645 /* timer_pending always called within inst->lock, so there
646 * is no chance of a race here */
647 else if (!timer_pending(&inst->timer)) {
648 instance_get(inst);
649 inst->timer.expires = jiffies + (inst->flushtimeout*HZ/100);
650 add_timer(&inst->timer);
651 }
652
653 unlock_and_release:
654 spin_unlock_bh(&inst->lock);
655 instance_put(inst);
656 return;
657
658 alloc_failure:
659 /* FIXME: statistics */
660 goto unlock_and_release;
661 }
662 EXPORT_SYMBOL_GPL(nfulnl_log_packet);
663
664 static int
665 nfulnl_rcv_nl_event(struct notifier_block *this,
666 unsigned long event, void *ptr)
667 {
668 struct netlink_notify *n = ptr;
669
670 if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
671 int i;
672
673 /* destroy all instances for this pid */
674 write_lock_bh(&instances_lock);
675 for (i = 0; i < INSTANCE_BUCKETS; i++) {
676 struct hlist_node *tmp, *t2;
677 struct nfulnl_instance *inst;
678 struct hlist_head *head = &instance_table[i];
679
680 hlist_for_each_entry_safe(inst, tmp, t2, head, hlist) {
681 if ((net_eq(n->net, &init_net)) &&
682 (n->pid == inst->peer_pid))
683 __instance_destroy(inst);
684 }
685 }
686 write_unlock_bh(&instances_lock);
687 }
688 return NOTIFY_DONE;
689 }
690
691 static struct notifier_block nfulnl_rtnl_notifier = {
692 .notifier_call = nfulnl_rcv_nl_event,
693 };
694
695 static int
696 nfulnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb,
697 const struct nlmsghdr *nlh,
698 const struct nlattr * const nfqa[])
699 {
700 return -ENOTSUPP;
701 }
702
703 static struct nf_logger nfulnl_logger __read_mostly = {
704 .name = "nfnetlink_log",
705 .logfn = &nfulnl_log_packet,
706 .me = THIS_MODULE,
707 };
708
709 static const struct nla_policy nfula_cfg_policy[NFULA_CFG_MAX+1] = {
710 [NFULA_CFG_CMD] = { .len = sizeof(struct nfulnl_msg_config_cmd) },
711 [NFULA_CFG_MODE] = { .len = sizeof(struct nfulnl_msg_config_mode) },
712 [NFULA_CFG_TIMEOUT] = { .type = NLA_U32 },
713 [NFULA_CFG_QTHRESH] = { .type = NLA_U32 },
714 [NFULA_CFG_NLBUFSIZ] = { .type = NLA_U32 },
715 [NFULA_CFG_FLAGS] = { .type = NLA_U16 },
716 };
717
718 static int
719 nfulnl_recv_config(struct sock *ctnl, struct sk_buff *skb,
720 const struct nlmsghdr *nlh,
721 const struct nlattr * const nfula[])
722 {
723 struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
724 u_int16_t group_num = ntohs(nfmsg->res_id);
725 struct nfulnl_instance *inst;
726 struct nfulnl_msg_config_cmd *cmd = NULL;
727 int ret = 0;
728
729 if (nfula[NFULA_CFG_CMD]) {
730 u_int8_t pf = nfmsg->nfgen_family;
731 cmd = nla_data(nfula[NFULA_CFG_CMD]);
732
733 /* Commands without queue context */
734 switch (cmd->command) {
735 case NFULNL_CFG_CMD_PF_BIND:
736 return nf_log_bind_pf(pf, &nfulnl_logger);
737 case NFULNL_CFG_CMD_PF_UNBIND:
738 nf_log_unbind_pf(pf);
739 return 0;
740 }
741 }
742
743 inst = instance_lookup_get(group_num);
744 if (inst && inst->peer_pid != NETLINK_CB(skb).pid) {
745 ret = -EPERM;
746 goto out_put;
747 }
748
749 if (cmd != NULL) {
750 switch (cmd->command) {
751 case NFULNL_CFG_CMD_BIND:
752 if (inst) {
753 ret = -EBUSY;
754 goto out_put;
755 }
756
757 inst = instance_create(group_num,
758 NETLINK_CB(skb).pid);
759 if (IS_ERR(inst)) {
760 ret = PTR_ERR(inst);
761 goto out;
762 }
763 break;
764 case NFULNL_CFG_CMD_UNBIND:
765 if (!inst) {
766 ret = -ENODEV;
767 goto out;
768 }
769
770 instance_destroy(inst);
771 goto out_put;
772 default:
773 ret = -ENOTSUPP;
774 break;
775 }
776 }
777
778 if (nfula[NFULA_CFG_MODE]) {
779 struct nfulnl_msg_config_mode *params;
780 params = nla_data(nfula[NFULA_CFG_MODE]);
781
782 if (!inst) {
783 ret = -ENODEV;
784 goto out;
785 }
786 nfulnl_set_mode(inst, params->copy_mode,
787 ntohl(params->copy_range));
788 }
789
790 if (nfula[NFULA_CFG_TIMEOUT]) {
791 __be32 timeout = nla_get_be32(nfula[NFULA_CFG_TIMEOUT]);
792
793 if (!inst) {
794 ret = -ENODEV;
795 goto out;
796 }
797 nfulnl_set_timeout(inst, ntohl(timeout));
798 }
799
800 if (nfula[NFULA_CFG_NLBUFSIZ]) {
801 __be32 nlbufsiz = nla_get_be32(nfula[NFULA_CFG_NLBUFSIZ]);
802
803 if (!inst) {
804 ret = -ENODEV;
805 goto out;
806 }
807 nfulnl_set_nlbufsiz(inst, ntohl(nlbufsiz));
808 }
809
810 if (nfula[NFULA_CFG_QTHRESH]) {
811 __be32 qthresh = nla_get_be32(nfula[NFULA_CFG_QTHRESH]);
812
813 if (!inst) {
814 ret = -ENODEV;
815 goto out;
816 }
817 nfulnl_set_qthresh(inst, ntohl(qthresh));
818 }
819
820 if (nfula[NFULA_CFG_FLAGS]) {
821 __be16 flags = nla_get_be16(nfula[NFULA_CFG_FLAGS]);
822
823 if (!inst) {
824 ret = -ENODEV;
825 goto out;
826 }
827 nfulnl_set_flags(inst, ntohs(flags));
828 }
829
830 out_put:
831 instance_put(inst);
832 out:
833 return ret;
834 }
835
836 static const struct nfnl_callback nfulnl_cb[NFULNL_MSG_MAX] = {
837 [NFULNL_MSG_PACKET] = { .call = nfulnl_recv_unsupp,
838 .attr_count = NFULA_MAX, },
839 [NFULNL_MSG_CONFIG] = { .call = nfulnl_recv_config,
840 .attr_count = NFULA_CFG_MAX,
841 .policy = nfula_cfg_policy },
842 };
843
844 static const struct nfnetlink_subsystem nfulnl_subsys = {
845 .name = "log",
846 .subsys_id = NFNL_SUBSYS_ULOG,
847 .cb_count = NFULNL_MSG_MAX,
848 .cb = nfulnl_cb,
849 };
850
851 #ifdef CONFIG_PROC_FS
852 struct iter_state {
853 unsigned int bucket;
854 };
855
856 static struct hlist_node *get_first(struct iter_state *st)
857 {
858 if (!st)
859 return NULL;
860
861 for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
862 if (!hlist_empty(&instance_table[st->bucket]))
863 return instance_table[st->bucket].first;
864 }
865 return NULL;
866 }
867
868 static struct hlist_node *get_next(struct iter_state *st, struct hlist_node *h)
869 {
870 h = h->next;
871 while (!h) {
872 if (++st->bucket >= INSTANCE_BUCKETS)
873 return NULL;
874
875 h = instance_table[st->bucket].first;
876 }
877 return h;
878 }
879
880 static struct hlist_node *get_idx(struct iter_state *st, loff_t pos)
881 {
882 struct hlist_node *head;
883 head = get_first(st);
884
885 if (head)
886 while (pos && (head = get_next(st, head)))
887 pos--;
888 return pos ? NULL : head;
889 }
890
891 static void *seq_start(struct seq_file *seq, loff_t *pos)
892 __acquires(instances_lock)
893 {
894 read_lock_bh(&instances_lock);
895 return get_idx(seq->private, *pos);
896 }
897
898 static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
899 {
900 (*pos)++;
901 return get_next(s->private, v);
902 }
903
904 static void seq_stop(struct seq_file *s, void *v)
905 __releases(instances_lock)
906 {
907 read_unlock_bh(&instances_lock);
908 }
909
910 static int seq_show(struct seq_file *s, void *v)
911 {
912 const struct nfulnl_instance *inst = v;
913
914 return seq_printf(s, "%5d %6d %5d %1d %5d %6d %2d\n",
915 inst->group_num,
916 inst->peer_pid, inst->qlen,
917 inst->copy_mode, inst->copy_range,
918 inst->flushtimeout, atomic_read(&inst->use));
919 }
920
921 static const struct seq_operations nful_seq_ops = {
922 .start = seq_start,
923 .next = seq_next,
924 .stop = seq_stop,
925 .show = seq_show,
926 };
927
928 static int nful_open(struct inode *inode, struct file *file)
929 {
930 return seq_open_private(file, &nful_seq_ops,
931 sizeof(struct iter_state));
932 }
933
934 static const struct file_operations nful_file_ops = {
935 .owner = THIS_MODULE,
936 .open = nful_open,
937 .read = seq_read,
938 .llseek = seq_lseek,
939 .release = seq_release_private,
940 };
941
942 #endif /* PROC_FS */
943
944 static int __init nfnetlink_log_init(void)
945 {
946 int i, status = -ENOMEM;
947
948 for (i = 0; i < INSTANCE_BUCKETS; i++)
949 INIT_HLIST_HEAD(&instance_table[i]);
950
951 /* it's not really all that important to have a random value, so
952 * we can do this from the init function, even if there hasn't
953 * been that much entropy yet */
954 get_random_bytes(&hash_init, sizeof(hash_init));
955
956 netlink_register_notifier(&nfulnl_rtnl_notifier);
957 status = nfnetlink_subsys_register(&nfulnl_subsys);
958 if (status < 0) {
959 printk(KERN_ERR "log: failed to create netlink socket\n");
960 goto cleanup_netlink_notifier;
961 }
962
963 status = nf_log_register(NFPROTO_UNSPEC, &nfulnl_logger);
964 if (status < 0) {
965 printk(KERN_ERR "log: failed to register logger\n");
966 goto cleanup_subsys;
967 }
968
969 #ifdef CONFIG_PROC_FS
970 if (!proc_create("nfnetlink_log", 0440,
971 proc_net_netfilter, &nful_file_ops))
972 goto cleanup_logger;
973 #endif
974 return status;
975
976 #ifdef CONFIG_PROC_FS
977 cleanup_logger:
978 nf_log_unregister(&nfulnl_logger);
979 #endif
980 cleanup_subsys:
981 nfnetlink_subsys_unregister(&nfulnl_subsys);
982 cleanup_netlink_notifier:
983 netlink_unregister_notifier(&nfulnl_rtnl_notifier);
984 return status;
985 }
986
987 static void __exit nfnetlink_log_fini(void)
988 {
989 nf_log_unregister(&nfulnl_logger);
990 #ifdef CONFIG_PROC_FS
991 remove_proc_entry("nfnetlink_log", proc_net_netfilter);
992 #endif
993 nfnetlink_subsys_unregister(&nfulnl_subsys);
994 netlink_unregister_notifier(&nfulnl_rtnl_notifier);
995 }
996
997 MODULE_DESCRIPTION("netfilter userspace logging");
998 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
999 MODULE_LICENSE("GPL");
1000 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_ULOG);
1001
1002 module_init(nfnetlink_log_init);
1003 module_exit(nfnetlink_log_fini);
Linux with added FPC-III support