?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
dm thin: wake worker when discard is prepared
[linux-2.6.git] / net / netfilter / nfnetlink_log.c
blob9f199f2e31fae16ff667e7a1f230e6826d015794
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 <linux/slab.h>
32 #include <net/sock.h>
33 #include <net/netfilter/nf_log.h>
34 #include <net/netfilter/nfnetlink_log.h>
35
36 #include <linux/atomic.h>
37
38 #ifdef CONFIG_BRIDGE_NETFILTER
39 #include "../bridge/br_private.h"
40 #endif
41
42 #define NFULNL_NLBUFSIZ_DEFAULT NLMSG_GOODSIZE
43 #define NFULNL_TIMEOUT_DEFAULT 100 /* every second */
44 #define NFULNL_QTHRESH_DEFAULT 100 /* 100 packets */
45 #define NFULNL_COPY_RANGE_MAX 0xFFFF /* max packet size is limited by 16-bit struct nfattr nfa_len field */
46
47 #define PRINTR(x, args...) do { if (net_ratelimit()) \
48 printk(x, ## args); } while (0);
49
50 struct nfulnl_instance {
51 struct hlist_node hlist; /* global list of instances */
52 spinlock_t lock;
53 atomic_t use; /* use count */
54
55 unsigned int qlen; /* number of nlmsgs in skb */
56 struct sk_buff *skb; /* pre-allocatd skb */
57 struct timer_list timer;
58 struct user_namespace *peer_user_ns; /* User namespace of the peer process */
59 int peer_portid; /* PORTID of the peer process */
60
61 /* configurable parameters */
62 unsigned int flushtimeout; /* timeout until queue flush */
63 unsigned int nlbufsiz; /* netlink buffer allocation size */
64 unsigned int qthreshold; /* threshold of the queue */
65 u_int32_t copy_range;
66 u_int32_t seq; /* instance-local sequential counter */
67 u_int16_t group_num; /* number of this queue */
68 u_int16_t flags;
69 u_int8_t copy_mode;
70 struct rcu_head rcu;
71 };
72
73 static DEFINE_SPINLOCK(instances_lock);
74 static atomic_t global_seq;
75
76 #define INSTANCE_BUCKETS 16
77 static struct hlist_head instance_table[INSTANCE_BUCKETS];
78 static unsigned int hash_init;
79
80 static inline u_int8_t instance_hashfn(u_int16_t group_num)
81 {
82 return ((group_num & 0xff) % INSTANCE_BUCKETS);
83 }
84
85 static struct nfulnl_instance *
86 __instance_lookup(u_int16_t group_num)
87 {
88 struct hlist_head *head;
89 struct hlist_node *pos;
90 struct nfulnl_instance *inst;
91
92 head = &instance_table[instance_hashfn(group_num)];
93 hlist_for_each_entry_rcu(inst, pos, head, hlist) {
94 if (inst->group_num == group_num)
95 return inst;
96 }
97 return NULL;
98 }
99
100 static inline void
101 instance_get(struct nfulnl_instance *inst)
102 {
103 atomic_inc(&inst->use);
104 }
105
106 static struct nfulnl_instance *
107 instance_lookup_get(u_int16_t group_num)
108 {
109 struct nfulnl_instance *inst;
110
111 rcu_read_lock_bh();
112 inst = __instance_lookup(group_num);
113 if (inst && !atomic_inc_not_zero(&inst->use))
114 inst = NULL;
115 rcu_read_unlock_bh();
116
117 return inst;
118 }
119
120 static void nfulnl_instance_free_rcu(struct rcu_head *head)
121 {
122 kfree(container_of(head, struct nfulnl_instance, rcu));
123 module_put(THIS_MODULE);
124 }
125
126 static void
127 instance_put(struct nfulnl_instance *inst)
128 {
129 if (inst && atomic_dec_and_test(&inst->use))
130 call_rcu_bh(&inst->rcu, nfulnl_instance_free_rcu);
131 }
132
133 static void nfulnl_timer(unsigned long data);
134
135 static struct nfulnl_instance *
136 instance_create(u_int16_t group_num, int portid, struct user_namespace *user_ns)
137 {
138 struct nfulnl_instance *inst;
139 int err;
140
141 spin_lock_bh(&instances_lock);
142 if (__instance_lookup(group_num)) {
143 err = -EEXIST;
144 goto out_unlock;
145 }
146
147 inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
148 if (!inst) {
149 err = -ENOMEM;
150 goto out_unlock;
151 }
152
153 if (!try_module_get(THIS_MODULE)) {
154 kfree(inst);
155 err = -EAGAIN;
156 goto out_unlock;
157 }
158
159 INIT_HLIST_NODE(&inst->hlist);
160 spin_lock_init(&inst->lock);
161 /* needs to be two, since we _put() after creation */
162 atomic_set(&inst->use, 2);
163
164 setup_timer(&inst->timer, nfulnl_timer, (unsigned long)inst);
165
166 inst->peer_user_ns = user_ns;
167 inst->peer_portid = portid;
168 inst->group_num = group_num;
169
170 inst->qthreshold = NFULNL_QTHRESH_DEFAULT;
171 inst->flushtimeout = NFULNL_TIMEOUT_DEFAULT;
172 inst->nlbufsiz = NFULNL_NLBUFSIZ_DEFAULT;
173 inst->copy_mode = NFULNL_COPY_PACKET;
174 inst->copy_range = NFULNL_COPY_RANGE_MAX;
175
176 hlist_add_head_rcu(&inst->hlist,
177 &instance_table[instance_hashfn(group_num)]);
178
179 spin_unlock_bh(&instances_lock);
180
181 return inst;
182
183 out_unlock:
184 spin_unlock_bh(&instances_lock);
185 return ERR_PTR(err);
186 }
187
188 static void __nfulnl_flush(struct nfulnl_instance *inst);
189
190 /* called with BH disabled */
191 static void
192 __instance_destroy(struct nfulnl_instance *inst)
193 {
194 /* first pull it out of the global list */
195 hlist_del_rcu(&inst->hlist);
196
197 /* then flush all pending packets from skb */
198
199 spin_lock(&inst->lock);
200
201 /* lockless readers wont be able to use us */
202 inst->copy_mode = NFULNL_COPY_DISABLED;
203
204 if (inst->skb)
205 __nfulnl_flush(inst);
206 spin_unlock(&inst->lock);
207
208 /* and finally put the refcount */
209 instance_put(inst);
210 }
211
212 static inline void
213 instance_destroy(struct nfulnl_instance *inst)
214 {
215 spin_lock_bh(&instances_lock);
216 __instance_destroy(inst);
217 spin_unlock_bh(&instances_lock);
218 }
219
220 static int
221 nfulnl_set_mode(struct nfulnl_instance *inst, u_int8_t mode,
222 unsigned int range)
223 {
224 int status = 0;
225
226 spin_lock_bh(&inst->lock);
227
228 switch (mode) {
229 case NFULNL_COPY_NONE:
230 case NFULNL_COPY_META:
231 inst->copy_mode = mode;
232 inst->copy_range = 0;
233 break;
234
235 case NFULNL_COPY_PACKET:
236 inst->copy_mode = mode;
237 inst->copy_range = min_t(unsigned int,
238 range, NFULNL_COPY_RANGE_MAX);
239 break;
240
241 default:
242 status = -EINVAL;
243 break;
244 }
245
246 spin_unlock_bh(&inst->lock);
247
248 return status;
249 }
250
251 static int
252 nfulnl_set_nlbufsiz(struct nfulnl_instance *inst, u_int32_t nlbufsiz)
253 {
254 int status;
255
256 spin_lock_bh(&inst->lock);
257 if (nlbufsiz < NFULNL_NLBUFSIZ_DEFAULT)
258 status = -ERANGE;
259 else if (nlbufsiz > 131072)
260 status = -ERANGE;
261 else {
262 inst->nlbufsiz = nlbufsiz;
263 status = 0;
264 }
265 spin_unlock_bh(&inst->lock);
266
267 return status;
268 }
269
270 static int
271 nfulnl_set_timeout(struct nfulnl_instance *inst, u_int32_t timeout)
272 {
273 spin_lock_bh(&inst->lock);
274 inst->flushtimeout = timeout;
275 spin_unlock_bh(&inst->lock);
276
277 return 0;
278 }
279
280 static int
281 nfulnl_set_qthresh(struct nfulnl_instance *inst, u_int32_t qthresh)
282 {
283 spin_lock_bh(&inst->lock);
284 inst->qthreshold = qthresh;
285 spin_unlock_bh(&inst->lock);
286
287 return 0;
288 }
289
290 static int
291 nfulnl_set_flags(struct nfulnl_instance *inst, u_int16_t flags)
292 {
293 spin_lock_bh(&inst->lock);
294 inst->flags = flags;
295 spin_unlock_bh(&inst->lock);
296
297 return 0;
298 }
299
300 static struct sk_buff *
301 nfulnl_alloc_skb(unsigned int inst_size, unsigned int pkt_size)
302 {
303 struct sk_buff *skb;
304 unsigned int n;
305
306 /* alloc skb which should be big enough for a whole multipart
307 * message. WARNING: has to be <= 128k due to slab restrictions */
308
309 n = max(inst_size, pkt_size);
310 skb = alloc_skb(n, GFP_ATOMIC);
311 if (!skb) {
312 if (n > pkt_size) {
313 /* try to allocate only as much as we need for current
314 * packet */
315
316 skb = alloc_skb(pkt_size, GFP_ATOMIC);
317 if (!skb)
318 pr_err("nfnetlink_log: can't even alloc %u bytes\n",
319 pkt_size);
320 }
321 }
322
323 return skb;
324 }
325
326 static int
327 __nfulnl_send(struct nfulnl_instance *inst)
328 {
329 int status = -1;
330
331 if (inst->qlen > 1) {
332 struct nlmsghdr *nlh = nlmsg_put(inst->skb, 0, 0,
333 NLMSG_DONE,
334 sizeof(struct nfgenmsg),
335 0);
336 if (!nlh)
337 goto out;
338 }
339 status = nfnetlink_unicast(inst->skb, &init_net, inst->peer_portid,
340 MSG_DONTWAIT);
341
342 inst->qlen = 0;
343 inst->skb = NULL;
344 out:
345 return status;
346 }
347
348 static void
349 __nfulnl_flush(struct nfulnl_instance *inst)
350 {
351 /* timer holds a reference */
352 if (del_timer(&inst->timer))
353 instance_put(inst);
354 if (inst->skb)
355 __nfulnl_send(inst);
356 }
357
358 static void
359 nfulnl_timer(unsigned long data)
360 {
361 struct nfulnl_instance *inst = (struct nfulnl_instance *)data;
362
363 spin_lock_bh(&inst->lock);
364 if (inst->skb)
365 __nfulnl_send(inst);
366 spin_unlock_bh(&inst->lock);
367 instance_put(inst);
368 }
369
370 /* This is an inline function, we don't really care about a long
371 * list of arguments */
372 static inline int
373 __build_packet_message(struct nfulnl_instance *inst,
374 const struct sk_buff *skb,
375 unsigned int data_len,
376 u_int8_t pf,
377 unsigned int hooknum,
378 const struct net_device *indev,
379 const struct net_device *outdev,
380 const char *prefix, unsigned int plen)
381 {
382 struct nfulnl_msg_packet_hdr pmsg;
383 struct nlmsghdr *nlh;
384 struct nfgenmsg *nfmsg;
385 sk_buff_data_t old_tail = inst->skb->tail;
386 struct sock *sk;
387
388 nlh = nlmsg_put(inst->skb, 0, 0,
389 NFNL_SUBSYS_ULOG << 8 | NFULNL_MSG_PACKET,
390 sizeof(struct nfgenmsg), 0);
391 if (!nlh)
392 return -1;
393 nfmsg = nlmsg_data(nlh);
394 nfmsg->nfgen_family = pf;
395 nfmsg->version = NFNETLINK_V0;
396 nfmsg->res_id = htons(inst->group_num);
397
398 pmsg.hw_protocol = skb->protocol;
399 pmsg.hook = hooknum;
400
401 if (nla_put(inst->skb, NFULA_PACKET_HDR, sizeof(pmsg), &pmsg))
402 goto nla_put_failure;
403
404 if (prefix &&
405 nla_put(inst->skb, NFULA_PREFIX, plen, prefix))
406 goto nla_put_failure;
407
408 if (indev) {
409 #ifndef CONFIG_BRIDGE_NETFILTER
410 if (nla_put_be32(inst->skb, NFULA_IFINDEX_INDEV,
411 htonl(indev->ifindex)))
412 goto nla_put_failure;
413 #else
414 if (pf == PF_BRIDGE) {
415 /* Case 1: outdev is physical input device, we need to
416 * look for bridge group (when called from
417 * netfilter_bridge) */
418 if (nla_put_be32(inst->skb, NFULA_IFINDEX_PHYSINDEV,
419 htonl(indev->ifindex)) ||
420 /* this is the bridge group "brX" */
421 /* rcu_read_lock()ed by nf_hook_slow or nf_log_packet */
422 nla_put_be32(inst->skb, NFULA_IFINDEX_INDEV,
423 htonl(br_port_get_rcu(indev)->br->dev->ifindex)))
424 goto nla_put_failure;
425 } else {
426 /* Case 2: indev is bridge group, we need to look for
427 * physical device (when called from ipv4) */
428 if (nla_put_be32(inst->skb, NFULA_IFINDEX_INDEV,
429 htonl(indev->ifindex)))
430 goto nla_put_failure;
431 if (skb->nf_bridge && skb->nf_bridge->physindev &&
432 nla_put_be32(inst->skb, NFULA_IFINDEX_PHYSINDEV,
433 htonl(skb->nf_bridge->physindev->ifindex)))
434 goto nla_put_failure;
435 }
436 #endif
437 }
438
439 if (outdev) {
440 #ifndef CONFIG_BRIDGE_NETFILTER
441 if (nla_put_be32(inst->skb, NFULA_IFINDEX_OUTDEV,
442 htonl(outdev->ifindex)))
443 goto nla_put_failure;
444 #else
445 if (pf == PF_BRIDGE) {
446 /* Case 1: outdev is physical output device, we need to
447 * look for bridge group (when called from
448 * netfilter_bridge) */
449 if (nla_put_be32(inst->skb, NFULA_IFINDEX_PHYSOUTDEV,
450 htonl(outdev->ifindex)) ||
451 /* this is the bridge group "brX" */
452 /* rcu_read_lock()ed by nf_hook_slow or nf_log_packet */
453 nla_put_be32(inst->skb, NFULA_IFINDEX_OUTDEV,
454 htonl(br_port_get_rcu(outdev)->br->dev->ifindex)))
455 goto nla_put_failure;
456 } else {
457 /* Case 2: indev is a bridge group, we need to look
458 * for physical device (when called from ipv4) */
459 if (nla_put_be32(inst->skb, NFULA_IFINDEX_OUTDEV,
460 htonl(outdev->ifindex)))
461 goto nla_put_failure;
462 if (skb->nf_bridge && skb->nf_bridge->physoutdev &&
463 nla_put_be32(inst->skb, NFULA_IFINDEX_PHYSOUTDEV,
464 htonl(skb->nf_bridge->physoutdev->ifindex)))
465 goto nla_put_failure;
466 }
467 #endif
468 }
469
470 if (skb->mark &&
471 nla_put_be32(inst->skb, NFULA_MARK, htonl(skb->mark)))
472 goto nla_put_failure;
473
474 if (indev && skb->dev &&
475 skb->mac_header != skb->network_header) {
476 struct nfulnl_msg_packet_hw phw;
477 int len = dev_parse_header(skb, phw.hw_addr);
478 if (len > 0) {
479 phw.hw_addrlen = htons(len);
480 if (nla_put(inst->skb, NFULA_HWADDR, sizeof(phw), &phw))
481 goto nla_put_failure;
482 }
483 }
484
485 if (indev && skb_mac_header_was_set(skb)) {
486 if (nla_put_be16(inst->skb, NFULA_HWTYPE, htons(skb->dev->type)) ||
487 nla_put_be16(inst->skb, NFULA_HWLEN,
488 htons(skb->dev->hard_header_len)) ||
489 nla_put(inst->skb, NFULA_HWHEADER, skb->dev->hard_header_len,
490 skb_mac_header(skb)))
491 goto nla_put_failure;
492 }
493
494 if (skb->tstamp.tv64) {
495 struct nfulnl_msg_packet_timestamp ts;
496 struct timeval tv = ktime_to_timeval(skb->tstamp);
497 ts.sec = cpu_to_be64(tv.tv_sec);
498 ts.usec = cpu_to_be64(tv.tv_usec);
499
500 if (nla_put(inst->skb, NFULA_TIMESTAMP, sizeof(ts), &ts))
501 goto nla_put_failure;
502 }
503
504 /* UID */
505 sk = skb->sk;
506 if (sk && sk->sk_state != TCP_TIME_WAIT) {
507 read_lock_bh(&sk->sk_callback_lock);
508 if (sk->sk_socket && sk->sk_socket->file) {
509 struct file *file = sk->sk_socket->file;
510 const struct cred *cred = file->f_cred;
511 struct user_namespace *user_ns = inst->peer_user_ns;
512 __be32 uid = htonl(from_kuid_munged(user_ns, cred->fsuid));
513 __be32 gid = htonl(from_kgid_munged(user_ns, cred->fsgid));
514 read_unlock_bh(&sk->sk_callback_lock);
515 if (nla_put_be32(inst->skb, NFULA_UID, uid) ||
516 nla_put_be32(inst->skb, NFULA_GID, gid))
517 goto nla_put_failure;
518 } else
519 read_unlock_bh(&sk->sk_callback_lock);
520 }
521
522 /* local sequence number */
523 if ((inst->flags & NFULNL_CFG_F_SEQ) &&
524 nla_put_be32(inst->skb, NFULA_SEQ, htonl(inst->seq++)))
525 goto nla_put_failure;
526
527 /* global sequence number */
528 if ((inst->flags & NFULNL_CFG_F_SEQ_GLOBAL) &&
529 nla_put_be32(inst->skb, NFULA_SEQ_GLOBAL,
530 htonl(atomic_inc_return(&global_seq))))
531 goto nla_put_failure;
532
533 if (data_len) {
534 struct nlattr *nla;
535 int size = nla_attr_size(data_len);
536
537 if (skb_tailroom(inst->skb) < nla_total_size(data_len)) {
538 printk(KERN_WARNING "nfnetlink_log: no tailroom!\n");
539 return -1;
540 }
541
542 nla = (struct nlattr *)skb_put(inst->skb, nla_total_size(data_len));
543 nla->nla_type = NFULA_PAYLOAD;
544 nla->nla_len = size;
545
546 if (skb_copy_bits(skb, 0, nla_data(nla), data_len))
547 BUG();
548 }
549
550 nlh->nlmsg_len = inst->skb->tail - old_tail;
551 return 0;
552
553 nla_put_failure:
554 PRINTR(KERN_ERR "nfnetlink_log: error creating log nlmsg\n");
555 return -1;
556 }
557
558 #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
559
560 static struct nf_loginfo default_loginfo = {
561 .type = NF_LOG_TYPE_ULOG,
562 .u = {
563 .ulog = {
564 .copy_len = 0xffff,
565 .group = 0,
566 .qthreshold = 1,
567 },
568 },
569 };
570
571 /* log handler for internal netfilter logging api */
572 void
573 nfulnl_log_packet(u_int8_t pf,
574 unsigned int hooknum,
575 const struct sk_buff *skb,
576 const struct net_device *in,
577 const struct net_device *out,
578 const struct nf_loginfo *li_user,
579 const char *prefix)
580 {
581 unsigned int size, data_len;
582 struct nfulnl_instance *inst;
583 const struct nf_loginfo *li;
584 unsigned int qthreshold;
585 unsigned int plen;
586
587 if (li_user && li_user->type == NF_LOG_TYPE_ULOG)
588 li = li_user;
589 else
590 li = &default_loginfo;
591
592 inst = instance_lookup_get(li->u.ulog.group);
593 if (!inst)
594 return;
595
596 plen = 0;
597 if (prefix)
598 plen = strlen(prefix) + 1;
599
600 /* FIXME: do we want to make the size calculation conditional based on
601 * what is actually present? way more branches and checks, but more
602 * memory efficient... */
603 size = NLMSG_SPACE(sizeof(struct nfgenmsg))
604 + nla_total_size(sizeof(struct nfulnl_msg_packet_hdr))
605 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
606 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
607 #ifdef CONFIG_BRIDGE_NETFILTER
608 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
609 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
610 #endif
611 + nla_total_size(sizeof(u_int32_t)) /* mark */
612 + nla_total_size(sizeof(u_int32_t)) /* uid */
613 + nla_total_size(sizeof(u_int32_t)) /* gid */
614 + nla_total_size(plen) /* prefix */
615 + nla_total_size(sizeof(struct nfulnl_msg_packet_hw))
616 + nla_total_size(sizeof(struct nfulnl_msg_packet_timestamp));
617
618 if (in && skb_mac_header_was_set(skb)) {
619 size += nla_total_size(skb->dev->hard_header_len)
620 + nla_total_size(sizeof(u_int16_t)) /* hwtype */
621 + nla_total_size(sizeof(u_int16_t)); /* hwlen */
622 }
623
624 spin_lock_bh(&inst->lock);
625
626 if (inst->flags & NFULNL_CFG_F_SEQ)
627 size += nla_total_size(sizeof(u_int32_t));
628 if (inst->flags & NFULNL_CFG_F_SEQ_GLOBAL)
629 size += nla_total_size(sizeof(u_int32_t));
630
631 qthreshold = inst->qthreshold;
632 /* per-rule qthreshold overrides per-instance */
633 if (li->u.ulog.qthreshold)
634 if (qthreshold > li->u.ulog.qthreshold)
635 qthreshold = li->u.ulog.qthreshold;
636
637
638 switch (inst->copy_mode) {
639 case NFULNL_COPY_META:
640 case NFULNL_COPY_NONE:
641 data_len = 0;
642 break;
643
644 case NFULNL_COPY_PACKET:
645 if (inst->copy_range == 0
646 || inst->copy_range > skb->len)
647 data_len = skb->len;
648 else
649 data_len = inst->copy_range;
650
651 size += nla_total_size(data_len);
652 break;
653
654 case NFULNL_COPY_DISABLED:
655 default:
656 goto unlock_and_release;
657 }
658
659 if (inst->skb &&
660 size > skb_tailroom(inst->skb) - sizeof(struct nfgenmsg)) {
661 /* either the queue len is too high or we don't have
662 * enough room in the skb left. flush to userspace. */
663 __nfulnl_flush(inst);
664 }
665
666 if (!inst->skb) {
667 inst->skb = nfulnl_alloc_skb(inst->nlbufsiz, size);
668 if (!inst->skb)
669 goto alloc_failure;
670 }
671
672 inst->qlen++;
673
674 __build_packet_message(inst, skb, data_len, pf,
675 hooknum, in, out, prefix, plen);
676
677 if (inst->qlen >= qthreshold)
678 __nfulnl_flush(inst);
679 /* timer_pending always called within inst->lock, so there
680 * is no chance of a race here */
681 else if (!timer_pending(&inst->timer)) {
682 instance_get(inst);
683 inst->timer.expires = jiffies + (inst->flushtimeout*HZ/100);
684 add_timer(&inst->timer);
685 }
686
687 unlock_and_release:
688 spin_unlock_bh(&inst->lock);
689 instance_put(inst);
690 return;
691
692 alloc_failure:
693 /* FIXME: statistics */
694 goto unlock_and_release;
695 }
696 EXPORT_SYMBOL_GPL(nfulnl_log_packet);
697
698 static int
699 nfulnl_rcv_nl_event(struct notifier_block *this,
700 unsigned long event, void *ptr)
701 {
702 struct netlink_notify *n = ptr;
703
704 if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
705 int i;
706
707 /* destroy all instances for this portid */
708 spin_lock_bh(&instances_lock);
709 for (i = 0; i < INSTANCE_BUCKETS; i++) {
710 struct hlist_node *tmp, *t2;
711 struct nfulnl_instance *inst;
712 struct hlist_head *head = &instance_table[i];
713
714 hlist_for_each_entry_safe(inst, tmp, t2, head, hlist) {
715 if ((net_eq(n->net, &init_net)) &&
716 (n->portid == inst->peer_portid))
717 __instance_destroy(inst);
718 }
719 }
720 spin_unlock_bh(&instances_lock);
721 }
722 return NOTIFY_DONE;
723 }
724
725 static struct notifier_block nfulnl_rtnl_notifier = {
726 .notifier_call = nfulnl_rcv_nl_event,
727 };
728
729 static int
730 nfulnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb,
731 const struct nlmsghdr *nlh,
732 const struct nlattr * const nfqa[])
733 {
734 return -ENOTSUPP;
735 }
736
737 static struct nf_logger nfulnl_logger __read_mostly = {
738 .name = "nfnetlink_log",
739 .logfn = &nfulnl_log_packet,
740 .me = THIS_MODULE,
741 };
742
743 static const struct nla_policy nfula_cfg_policy[NFULA_CFG_MAX+1] = {
744 [NFULA_CFG_CMD] = { .len = sizeof(struct nfulnl_msg_config_cmd) },
745 [NFULA_CFG_MODE] = { .len = sizeof(struct nfulnl_msg_config_mode) },
746 [NFULA_CFG_TIMEOUT] = { .type = NLA_U32 },
747 [NFULA_CFG_QTHRESH] = { .type = NLA_U32 },
748 [NFULA_CFG_NLBUFSIZ] = { .type = NLA_U32 },
749 [NFULA_CFG_FLAGS] = { .type = NLA_U16 },
750 };
751
752 static int
753 nfulnl_recv_config(struct sock *ctnl, struct sk_buff *skb,
754 const struct nlmsghdr *nlh,
755 const struct nlattr * const nfula[])
756 {
757 struct nfgenmsg *nfmsg = nlmsg_data(nlh);
758 u_int16_t group_num = ntohs(nfmsg->res_id);
759 struct nfulnl_instance *inst;
760 struct nfulnl_msg_config_cmd *cmd = NULL;
761 int ret = 0;
762
763 if (nfula[NFULA_CFG_CMD]) {
764 u_int8_t pf = nfmsg->nfgen_family;
765 cmd = nla_data(nfula[NFULA_CFG_CMD]);
766
767 /* Commands without queue context */
768 switch (cmd->command) {
769 case NFULNL_CFG_CMD_PF_BIND:
770 return nf_log_bind_pf(pf, &nfulnl_logger);
771 case NFULNL_CFG_CMD_PF_UNBIND:
772 nf_log_unbind_pf(pf);
773 return 0;
774 }
775 }
776
777 inst = instance_lookup_get(group_num);
778 if (inst && inst->peer_portid != NETLINK_CB(skb).portid) {
779 ret = -EPERM;
780 goto out_put;
781 }
782
783 if (cmd != NULL) {
784 switch (cmd->command) {
785 case NFULNL_CFG_CMD_BIND:
786 if (inst) {
787 ret = -EBUSY;
788 goto out_put;
789 }
790
791 inst = instance_create(group_num,
792 NETLINK_CB(skb).portid,
793 sk_user_ns(NETLINK_CB(skb).ssk));
794 if (IS_ERR(inst)) {
795 ret = PTR_ERR(inst);
796 goto out;
797 }
798 break;
799 case NFULNL_CFG_CMD_UNBIND:
800 if (!inst) {
801 ret = -ENODEV;
802 goto out;
803 }
804
805 instance_destroy(inst);
806 goto out_put;
807 default:
808 ret = -ENOTSUPP;
809 break;
810 }
811 }
812
813 if (nfula[NFULA_CFG_MODE]) {
814 struct nfulnl_msg_config_mode *params;
815 params = nla_data(nfula[NFULA_CFG_MODE]);
816
817 if (!inst) {
818 ret = -ENODEV;
819 goto out;
820 }
821 nfulnl_set_mode(inst, params->copy_mode,
822 ntohl(params->copy_range));
823 }
824
825 if (nfula[NFULA_CFG_TIMEOUT]) {
826 __be32 timeout = nla_get_be32(nfula[NFULA_CFG_TIMEOUT]);
827
828 if (!inst) {
829 ret = -ENODEV;
830 goto out;
831 }
832 nfulnl_set_timeout(inst, ntohl(timeout));
833 }
834
835 if (nfula[NFULA_CFG_NLBUFSIZ]) {
836 __be32 nlbufsiz = nla_get_be32(nfula[NFULA_CFG_NLBUFSIZ]);
837
838 if (!inst) {
839 ret = -ENODEV;
840 goto out;
841 }
842 nfulnl_set_nlbufsiz(inst, ntohl(nlbufsiz));
843 }
844
845 if (nfula[NFULA_CFG_QTHRESH]) {
846 __be32 qthresh = nla_get_be32(nfula[NFULA_CFG_QTHRESH]);
847
848 if (!inst) {
849 ret = -ENODEV;
850 goto out;
851 }
852 nfulnl_set_qthresh(inst, ntohl(qthresh));
853 }
854
855 if (nfula[NFULA_CFG_FLAGS]) {
856 __be16 flags = nla_get_be16(nfula[NFULA_CFG_FLAGS]);
857
858 if (!inst) {
859 ret = -ENODEV;
860 goto out;
861 }
862 nfulnl_set_flags(inst, ntohs(flags));
863 }
864
865 out_put:
866 instance_put(inst);
867 out:
868 return ret;
869 }
870
871 static const struct nfnl_callback nfulnl_cb[NFULNL_MSG_MAX] = {
872 [NFULNL_MSG_PACKET] = { .call = nfulnl_recv_unsupp,
873 .attr_count = NFULA_MAX, },
874 [NFULNL_MSG_CONFIG] = { .call = nfulnl_recv_config,
875 .attr_count = NFULA_CFG_MAX,
876 .policy = nfula_cfg_policy },
877 };
878
879 static const struct nfnetlink_subsystem nfulnl_subsys = {
880 .name = "log",
881 .subsys_id = NFNL_SUBSYS_ULOG,
882 .cb_count = NFULNL_MSG_MAX,
883 .cb = nfulnl_cb,
884 };
885
886 #ifdef CONFIG_PROC_FS
887 struct iter_state {
888 unsigned int bucket;
889 };
890
891 static struct hlist_node *get_first(struct iter_state *st)
892 {
893 if (!st)
894 return NULL;
895
896 for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
897 if (!hlist_empty(&instance_table[st->bucket]))
898 return rcu_dereference_bh(hlist_first_rcu(&instance_table[st->bucket]));
899 }
900 return NULL;
901 }
902
903 static struct hlist_node *get_next(struct iter_state *st, struct hlist_node *h)
904 {
905 h = rcu_dereference_bh(hlist_next_rcu(h));
906 while (!h) {
907 if (++st->bucket >= INSTANCE_BUCKETS)
908 return NULL;
909
910 h = rcu_dereference_bh(hlist_first_rcu(&instance_table[st->bucket]));
911 }
912 return h;
913 }
914
915 static struct hlist_node *get_idx(struct iter_state *st, loff_t pos)
916 {
917 struct hlist_node *head;
918 head = get_first(st);
919
920 if (head)
921 while (pos && (head = get_next(st, head)))
922 pos--;
923 return pos ? NULL : head;
924 }
925
926 static void *seq_start(struct seq_file *seq, loff_t *pos)
927 __acquires(rcu_bh)
928 {
929 rcu_read_lock_bh();
930 return get_idx(seq->private, *pos);
931 }
932
933 static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
934 {
935 (*pos)++;
936 return get_next(s->private, v);
937 }
938
939 static void seq_stop(struct seq_file *s, void *v)
940 __releases(rcu_bh)
941 {
942 rcu_read_unlock_bh();
943 }
944
945 static int seq_show(struct seq_file *s, void *v)
946 {
947 const struct nfulnl_instance *inst = v;
948
949 return seq_printf(s, "%5d %6d %5d %1d %5d %6d %2d\n",
950 inst->group_num,
951 inst->peer_portid, inst->qlen,
952 inst->copy_mode, inst->copy_range,
953 inst->flushtimeout, atomic_read(&inst->use));
954 }
955
956 static const struct seq_operations nful_seq_ops = {
957 .start = seq_start,
958 .next = seq_next,
959 .stop = seq_stop,
960 .show = seq_show,
961 };
962
963 static int nful_open(struct inode *inode, struct file *file)
964 {
965 return seq_open_private(file, &nful_seq_ops,
966 sizeof(struct iter_state));
967 }
968
969 static const struct file_operations nful_file_ops = {
970 .owner = THIS_MODULE,
971 .open = nful_open,
972 .read = seq_read,
973 .llseek = seq_lseek,
974 .release = seq_release_private,
975 };
976
977 #endif /* PROC_FS */
978
979 static int __init nfnetlink_log_init(void)
980 {
981 int i, status = -ENOMEM;
982
983 for (i = 0; i < INSTANCE_BUCKETS; i++)
984 INIT_HLIST_HEAD(&instance_table[i]);
985
986 /* it's not really all that important to have a random value, so
987 * we can do this from the init function, even if there hasn't
988 * been that much entropy yet */
989 get_random_bytes(&hash_init, sizeof(hash_init));
990
991 netlink_register_notifier(&nfulnl_rtnl_notifier);
992 status = nfnetlink_subsys_register(&nfulnl_subsys);
993 if (status < 0) {
994 printk(KERN_ERR "log: failed to create netlink socket\n");
995 goto cleanup_netlink_notifier;
996 }
997
998 status = nf_log_register(NFPROTO_UNSPEC, &nfulnl_logger);
999 if (status < 0) {
1000 printk(KERN_ERR "log: failed to register logger\n");
1001 goto cleanup_subsys;
1002 }
1003
1004 #ifdef CONFIG_PROC_FS
1005 if (!proc_create("nfnetlink_log", 0440,
1006 proc_net_netfilter, &nful_file_ops)) {
1007 status = -ENOMEM;
1008 goto cleanup_logger;
1009 }
1010 #endif
1011 return status;
1012
1013 #ifdef CONFIG_PROC_FS
1014 cleanup_logger:
1015 nf_log_unregister(&nfulnl_logger);
1016 #endif
1017 cleanup_subsys:
1018 nfnetlink_subsys_unregister(&nfulnl_subsys);
1019 cleanup_netlink_notifier:
1020 netlink_unregister_notifier(&nfulnl_rtnl_notifier);
1021 return status;
1022 }
1023
1024 static void __exit nfnetlink_log_fini(void)
1025 {
1026 nf_log_unregister(&nfulnl_logger);
1027 #ifdef CONFIG_PROC_FS
1028 remove_proc_entry("nfnetlink_log", proc_net_netfilter);
1029 #endif
1030 nfnetlink_subsys_unregister(&nfulnl_subsys);
1031 netlink_unregister_notifier(&nfulnl_rtnl_notifier);
1032 }
1033
1034 MODULE_DESCRIPTION("netfilter userspace logging");
1035 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
1036 MODULE_LICENSE("GPL");
1037 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_ULOG);
1038
1039 module_init(nfnetlink_log_init);
1040 module_exit(nfnetlink_log_fini);
Linus' kernel tree