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13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <linux/module.h>
16#include <linux/skbuff.h>
17#include <linux/if_arp.h>
18#include <linux/init.h>
19#include <linux/ip.h>
20#include <linux/ipv6.h>
21#include <linux/netdevice.h>
22#include <linux/netfilter.h>
23#include <linux/netfilter_bridge.h>
24#include <net/netlink.h>
25#include <linux/netfilter/nfnetlink.h>
26#include <linux/netfilter/nfnetlink_log.h>
27#include <linux/netfilter/nf_conntrack_common.h>
28#include <linux/spinlock.h>
29#include <linux/sysctl.h>
30#include <linux/proc_fs.h>
31#include <linux/security.h>
32#include <linux/list.h>
33#include <linux/slab.h>
34#include <net/sock.h>
35#include <net/netfilter/nf_log.h>
36#include <net/netns/generic.h>
37
38#include <linux/atomic.h>
39#include <linux/refcount.h>
40
41
42#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
43#include "../bridge/br_private.h"
44#endif
45
46#if IS_ENABLED(CONFIG_NF_CONNTRACK)
47#include <net/netfilter/nf_conntrack.h>
48#endif
49
50#define NFULNL_COPY_DISABLED 0xff
51#define NFULNL_NLBUFSIZ_DEFAULT NLMSG_GOODSIZE
52#define NFULNL_TIMEOUT_DEFAULT 100
53#define NFULNL_QTHRESH_DEFAULT 100
54
55#define NFULNL_COPY_RANGE_MAX (0xFFFF - NLA_HDRLEN)
56
57#define PRINTR(x, args...) do { if (net_ratelimit()) \
58 printk(x, ## args); } while (0);
59
60struct nfulnl_instance {
61 struct hlist_node hlist;
62 spinlock_t lock;
63 refcount_t use;
64
65 unsigned int qlen;
66 struct sk_buff *skb;
67 struct timer_list timer;
68 struct net *net;
69 netns_tracker ns_tracker;
70 struct user_namespace *peer_user_ns;
71 u32 peer_portid;
72
73
74 unsigned int flushtimeout;
75 unsigned int nlbufsiz;
76 unsigned int qthreshold;
77 u_int32_t copy_range;
78 u_int32_t seq;
79 u_int16_t group_num;
80 u_int16_t flags;
81 u_int8_t copy_mode;
82 struct rcu_head rcu;
83};
84
85#define INSTANCE_BUCKETS 16
86
87static unsigned int nfnl_log_net_id __read_mostly;
88
89struct nfnl_log_net {
90 spinlock_t instances_lock;
91 struct hlist_head instance_table[INSTANCE_BUCKETS];
92 atomic_t global_seq;
93};
94
95static struct nfnl_log_net *nfnl_log_pernet(struct net *net)
96{
97 return net_generic(net, nfnl_log_net_id);
98}
99
100static inline u_int8_t instance_hashfn(u_int16_t group_num)
101{
102 return ((group_num & 0xff) % INSTANCE_BUCKETS);
103}
104
105static struct nfulnl_instance *
106__instance_lookup(struct nfnl_log_net *log, u_int16_t group_num)
107{
108 struct hlist_head *head;
109 struct nfulnl_instance *inst;
110
111 head = &log->instance_table[instance_hashfn(group_num)];
112 hlist_for_each_entry_rcu(inst, head, hlist) {
113 if (inst->group_num == group_num)
114 return inst;
115 }
116 return NULL;
117}
118
119static inline void
120instance_get(struct nfulnl_instance *inst)
121{
122 refcount_inc(&inst->use);
123}
124
125static struct nfulnl_instance *
126instance_lookup_get(struct nfnl_log_net *log, u_int16_t group_num)
127{
128 struct nfulnl_instance *inst;
129
130 rcu_read_lock_bh();
131 inst = __instance_lookup(log, group_num);
132 if (inst && !refcount_inc_not_zero(&inst->use))
133 inst = NULL;
134 rcu_read_unlock_bh();
135
136 return inst;
137}
138
139static void nfulnl_instance_free_rcu(struct rcu_head *head)
140{
141 struct nfulnl_instance *inst =
142 container_of(head, struct nfulnl_instance, rcu);
143
144 put_net_track(inst->net, &inst->ns_tracker);
145 kfree(inst);
146 module_put(THIS_MODULE);
147}
148
149static void
150instance_put(struct nfulnl_instance *inst)
151{
152 if (inst && refcount_dec_and_test(&inst->use))
153 call_rcu(&inst->rcu, nfulnl_instance_free_rcu);
154}
155
156static void nfulnl_timer(struct timer_list *t);
157
158static struct nfulnl_instance *
159instance_create(struct net *net, u_int16_t group_num,
160 u32 portid, struct user_namespace *user_ns)
161{
162 struct nfulnl_instance *inst;
163 struct nfnl_log_net *log = nfnl_log_pernet(net);
164 int err;
165
166 spin_lock_bh(&log->instances_lock);
167 if (__instance_lookup(log, group_num)) {
168 err = -EEXIST;
169 goto out_unlock;
170 }
171
172 inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
173 if (!inst) {
174 err = -ENOMEM;
175 goto out_unlock;
176 }
177
178 if (!try_module_get(THIS_MODULE)) {
179 kfree(inst);
180 err = -EAGAIN;
181 goto out_unlock;
182 }
183
184 INIT_HLIST_NODE(&inst->hlist);
185 spin_lock_init(&inst->lock);
186
187 refcount_set(&inst->use, 2);
188
189 timer_setup(&inst->timer, nfulnl_timer, 0);
190
191 inst->net = get_net_track(net, &inst->ns_tracker, GFP_ATOMIC);
192 inst->peer_user_ns = user_ns;
193 inst->peer_portid = portid;
194 inst->group_num = group_num;
195
196 inst->qthreshold = NFULNL_QTHRESH_DEFAULT;
197 inst->flushtimeout = NFULNL_TIMEOUT_DEFAULT;
198 inst->nlbufsiz = NFULNL_NLBUFSIZ_DEFAULT;
199 inst->copy_mode = NFULNL_COPY_PACKET;
200 inst->copy_range = NFULNL_COPY_RANGE_MAX;
201
202 hlist_add_head_rcu(&inst->hlist,
203 &log->instance_table[instance_hashfn(group_num)]);
204
205
206 spin_unlock_bh(&log->instances_lock);
207
208 return inst;
209
210out_unlock:
211 spin_unlock_bh(&log->instances_lock);
212 return ERR_PTR(err);
213}
214
215static void __nfulnl_flush(struct nfulnl_instance *inst);
216
217
218static void
219__instance_destroy(struct nfulnl_instance *inst)
220{
221
222 hlist_del_rcu(&inst->hlist);
223
224
225
226 spin_lock(&inst->lock);
227
228
229 inst->copy_mode = NFULNL_COPY_DISABLED;
230
231 if (inst->skb)
232 __nfulnl_flush(inst);
233 spin_unlock(&inst->lock);
234
235
236 instance_put(inst);
237}
238
239static inline void
240instance_destroy(struct nfnl_log_net *log,
241 struct nfulnl_instance *inst)
242{
243 spin_lock_bh(&log->instances_lock);
244 __instance_destroy(inst);
245 spin_unlock_bh(&log->instances_lock);
246}
247
248static int
249nfulnl_set_mode(struct nfulnl_instance *inst, u_int8_t mode,
250 unsigned int range)
251{
252 int status = 0;
253
254 spin_lock_bh(&inst->lock);
255
256 switch (mode) {
257 case NFULNL_COPY_NONE:
258 case NFULNL_COPY_META:
259 inst->copy_mode = mode;
260 inst->copy_range = 0;
261 break;
262
263 case NFULNL_COPY_PACKET:
264 inst->copy_mode = mode;
265 if (range == 0)
266 range = NFULNL_COPY_RANGE_MAX;
267 inst->copy_range = min_t(unsigned int,
268 range, NFULNL_COPY_RANGE_MAX);
269 break;
270
271 default:
272 status = -EINVAL;
273 break;
274 }
275
276 spin_unlock_bh(&inst->lock);
277
278 return status;
279}
280
281static int
282nfulnl_set_nlbufsiz(struct nfulnl_instance *inst, u_int32_t nlbufsiz)
283{
284 int status;
285
286 spin_lock_bh(&inst->lock);
287 if (nlbufsiz < NFULNL_NLBUFSIZ_DEFAULT)
288 status = -ERANGE;
289 else if (nlbufsiz > 131072)
290 status = -ERANGE;
291 else {
292 inst->nlbufsiz = nlbufsiz;
293 status = 0;
294 }
295 spin_unlock_bh(&inst->lock);
296
297 return status;
298}
299
300static void
301nfulnl_set_timeout(struct nfulnl_instance *inst, u_int32_t timeout)
302{
303 spin_lock_bh(&inst->lock);
304 inst->flushtimeout = timeout;
305 spin_unlock_bh(&inst->lock);
306}
307
308static void
309nfulnl_set_qthresh(struct nfulnl_instance *inst, u_int32_t qthresh)
310{
311 spin_lock_bh(&inst->lock);
312 inst->qthreshold = qthresh;
313 spin_unlock_bh(&inst->lock);
314}
315
316static int
317nfulnl_set_flags(struct nfulnl_instance *inst, u_int16_t flags)
318{
319 spin_lock_bh(&inst->lock);
320 inst->flags = flags;
321 spin_unlock_bh(&inst->lock);
322
323 return 0;
324}
325
326static struct sk_buff *
327nfulnl_alloc_skb(struct net *net, u32 peer_portid, unsigned int inst_size,
328 unsigned int pkt_size)
329{
330 struct sk_buff *skb;
331 unsigned int n;
332
333
334
335
336 n = max(inst_size, pkt_size);
337 skb = alloc_skb(n, GFP_ATOMIC | __GFP_NOWARN);
338 if (!skb) {
339 if (n > pkt_size) {
340
341
342
343 skb = alloc_skb(pkt_size, GFP_ATOMIC);
344 }
345 }
346
347 return skb;
348}
349
350static void
351__nfulnl_send(struct nfulnl_instance *inst)
352{
353 if (inst->qlen > 1) {
354 struct nlmsghdr *nlh = nlmsg_put(inst->skb, 0, 0,
355 NLMSG_DONE,
356 sizeof(struct nfgenmsg),
357 0);
358 if (WARN_ONCE(!nlh, "bad nlskb size: %u, tailroom %d\n",
359 inst->skb->len, skb_tailroom(inst->skb))) {
360 kfree_skb(inst->skb);
361 goto out;
362 }
363 }
364 nfnetlink_unicast(inst->skb, inst->net, inst->peer_portid);
365out:
366 inst->qlen = 0;
367 inst->skb = NULL;
368}
369
370static void
371__nfulnl_flush(struct nfulnl_instance *inst)
372{
373
374 if (del_timer(&inst->timer))
375 instance_put(inst);
376 if (inst->skb)
377 __nfulnl_send(inst);
378}
379
380static void
381nfulnl_timer(struct timer_list *t)
382{
383 struct nfulnl_instance *inst = from_timer(inst, t, timer);
384
385 spin_lock_bh(&inst->lock);
386 if (inst->skb)
387 __nfulnl_send(inst);
388 spin_unlock_bh(&inst->lock);
389 instance_put(inst);
390}
391
392static u32 nfulnl_get_bridge_size(const struct sk_buff *skb)
393{
394 u32 size = 0;
395
396 if (!skb_mac_header_was_set(skb))
397 return 0;
398
399 if (skb_vlan_tag_present(skb)) {
400 size += nla_total_size(0);
401 size += nla_total_size(sizeof(u16));
402 size += nla_total_size(sizeof(u16));
403 }
404
405 if (skb->network_header > skb->mac_header)
406 size += nla_total_size(skb->network_header - skb->mac_header);
407
408 return size;
409}
410
411static int nfulnl_put_bridge(struct nfulnl_instance *inst, const struct sk_buff *skb)
412{
413 if (!skb_mac_header_was_set(skb))
414 return 0;
415
416 if (skb_vlan_tag_present(skb)) {
417 struct nlattr *nest;
418
419 nest = nla_nest_start(inst->skb, NFULA_VLAN);
420 if (!nest)
421 goto nla_put_failure;
422
423 if (nla_put_be16(inst->skb, NFULA_VLAN_TCI, htons(skb->vlan_tci)) ||
424 nla_put_be16(inst->skb, NFULA_VLAN_PROTO, skb->vlan_proto))
425 goto nla_put_failure;
426
427 nla_nest_end(inst->skb, nest);
428 }
429
430 if (skb->mac_header < skb->network_header) {
431 int len = (int)(skb->network_header - skb->mac_header);
432
433 if (nla_put(inst->skb, NFULA_L2HDR, len, skb_mac_header(skb)))
434 goto nla_put_failure;
435 }
436
437 return 0;
438
439nla_put_failure:
440 return -1;
441}
442
443
444
445static inline int
446__build_packet_message(struct nfnl_log_net *log,
447 struct nfulnl_instance *inst,
448 const struct sk_buff *skb,
449 unsigned int data_len,
450 u_int8_t pf,
451 unsigned int hooknum,
452 const struct net_device *indev,
453 const struct net_device *outdev,
454 const char *prefix, unsigned int plen,
455 const struct nfnl_ct_hook *nfnl_ct,
456 struct nf_conn *ct, enum ip_conntrack_info ctinfo)
457{
458 struct nfulnl_msg_packet_hdr pmsg;
459 struct nlmsghdr *nlh;
460 sk_buff_data_t old_tail = inst->skb->tail;
461 struct sock *sk;
462 const unsigned char *hwhdrp;
463 ktime_t tstamp;
464
465 nlh = nfnl_msg_put(inst->skb, 0, 0,
466 nfnl_msg_type(NFNL_SUBSYS_ULOG, NFULNL_MSG_PACKET),
467 0, pf, NFNETLINK_V0, htons(inst->group_num));
468 if (!nlh)
469 return -1;
470
471 memset(&pmsg, 0, sizeof(pmsg));
472 pmsg.hw_protocol = skb->protocol;
473 pmsg.hook = hooknum;
474
475 if (nla_put(inst->skb, NFULA_PACKET_HDR, sizeof(pmsg), &pmsg))
476 goto nla_put_failure;
477
478 if (prefix &&
479 nla_put(inst->skb, NFULA_PREFIX, plen, prefix))
480 goto nla_put_failure;
481
482 if (indev) {
483#if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
484 if (nla_put_be32(inst->skb, NFULA_IFINDEX_INDEV,
485 htonl(indev->ifindex)))
486 goto nla_put_failure;
487#else
488 if (pf == PF_BRIDGE) {
489
490
491
492 if (nla_put_be32(inst->skb, NFULA_IFINDEX_PHYSINDEV,
493 htonl(indev->ifindex)) ||
494
495
496
497
498 nla_put_be32(inst->skb, NFULA_IFINDEX_INDEV,
499 htonl(br_port_get_rcu(indev)->br->dev->ifindex)))
500 goto nla_put_failure;
501 } else {
502 struct net_device *physindev;
503
504
505
506 if (nla_put_be32(inst->skb, NFULA_IFINDEX_INDEV,
507 htonl(indev->ifindex)))
508 goto nla_put_failure;
509
510 physindev = nf_bridge_get_physindev(skb);
511 if (physindev &&
512 nla_put_be32(inst->skb, NFULA_IFINDEX_PHYSINDEV,
513 htonl(physindev->ifindex)))
514 goto nla_put_failure;
515 }
516#endif
517 }
518
519 if (outdev) {
520#if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
521 if (nla_put_be32(inst->skb, NFULA_IFINDEX_OUTDEV,
522 htonl(outdev->ifindex)))
523 goto nla_put_failure;
524#else
525 if (pf == PF_BRIDGE) {
526
527
528
529 if (nla_put_be32(inst->skb, NFULA_IFINDEX_PHYSOUTDEV,
530 htonl(outdev->ifindex)) ||
531
532
533
534
535 nla_put_be32(inst->skb, NFULA_IFINDEX_OUTDEV,
536 htonl(br_port_get_rcu(outdev)->br->dev->ifindex)))
537 goto nla_put_failure;
538 } else {
539 struct net_device *physoutdev;
540
541
542
543 if (nla_put_be32(inst->skb, NFULA_IFINDEX_OUTDEV,
544 htonl(outdev->ifindex)))
545 goto nla_put_failure;
546
547 physoutdev = nf_bridge_get_physoutdev(skb);
548 if (physoutdev &&
549 nla_put_be32(inst->skb, NFULA_IFINDEX_PHYSOUTDEV,
550 htonl(physoutdev->ifindex)))
551 goto nla_put_failure;
552 }
553#endif
554 }
555
556 if (skb->mark &&
557 nla_put_be32(inst->skb, NFULA_MARK, htonl(skb->mark)))
558 goto nla_put_failure;
559
560 if (indev && skb->dev &&
561 skb_mac_header_was_set(skb) &&
562 skb_mac_header_len(skb) != 0) {
563 struct nfulnl_msg_packet_hw phw;
564 int len;
565
566 memset(&phw, 0, sizeof(phw));
567 len = dev_parse_header(skb, phw.hw_addr);
568 if (len > 0) {
569 phw.hw_addrlen = htons(len);
570 if (nla_put(inst->skb, NFULA_HWADDR, sizeof(phw), &phw))
571 goto nla_put_failure;
572 }
573 }
574
575 if (indev && skb_mac_header_was_set(skb)) {
576 if (nla_put_be16(inst->skb, NFULA_HWTYPE, htons(skb->dev->type)) ||
577 nla_put_be16(inst->skb, NFULA_HWLEN,
578 htons(skb->dev->hard_header_len)))
579 goto nla_put_failure;
580
581 hwhdrp = skb_mac_header(skb);
582
583 if (skb->dev->type == ARPHRD_SIT)
584 hwhdrp -= ETH_HLEN;
585
586 if (hwhdrp >= skb->head &&
587 nla_put(inst->skb, NFULA_HWHEADER,
588 skb->dev->hard_header_len, hwhdrp))
589 goto nla_put_failure;
590 }
591
592 tstamp = skb_tstamp_cond(skb, false);
593 if (hooknum <= NF_INET_FORWARD && tstamp) {
594 struct nfulnl_msg_packet_timestamp ts;
595 struct timespec64 kts = ktime_to_timespec64(tstamp);
596 ts.sec = cpu_to_be64(kts.tv_sec);
597 ts.usec = cpu_to_be64(kts.tv_nsec / NSEC_PER_USEC);
598
599 if (nla_put(inst->skb, NFULA_TIMESTAMP, sizeof(ts), &ts))
600 goto nla_put_failure;
601 }
602
603
604 sk = skb->sk;
605 if (sk && sk_fullsock(sk)) {
606 read_lock_bh(&sk->sk_callback_lock);
607 if (sk->sk_socket && sk->sk_socket->file) {
608 struct file *file = sk->sk_socket->file;
609 const struct cred *cred = file->f_cred;
610 struct user_namespace *user_ns = inst->peer_user_ns;
611 __be32 uid = htonl(from_kuid_munged(user_ns, cred->fsuid));
612 __be32 gid = htonl(from_kgid_munged(user_ns, cred->fsgid));
613 read_unlock_bh(&sk->sk_callback_lock);
614 if (nla_put_be32(inst->skb, NFULA_UID, uid) ||
615 nla_put_be32(inst->skb, NFULA_GID, gid))
616 goto nla_put_failure;
617 } else
618 read_unlock_bh(&sk->sk_callback_lock);
619 }
620
621
622 if ((inst->flags & NFULNL_CFG_F_SEQ) &&
623 nla_put_be32(inst->skb, NFULA_SEQ, htonl(inst->seq++)))
624 goto nla_put_failure;
625
626
627 if ((inst->flags & NFULNL_CFG_F_SEQ_GLOBAL) &&
628 nla_put_be32(inst->skb, NFULA_SEQ_GLOBAL,
629 htonl(atomic_inc_return(&log->global_seq))))
630 goto nla_put_failure;
631
632 if (ct && nfnl_ct->build(inst->skb, ct, ctinfo,
633 NFULA_CT, NFULA_CT_INFO) < 0)
634 goto nla_put_failure;
635
636 if ((pf == NFPROTO_NETDEV || pf == NFPROTO_BRIDGE) &&
637 nfulnl_put_bridge(inst, skb) < 0)
638 goto nla_put_failure;
639
640 if (data_len) {
641 struct nlattr *nla;
642 int size = nla_attr_size(data_len);
643
644 if (skb_tailroom(inst->skb) < nla_total_size(data_len))
645 goto nla_put_failure;
646
647 nla = skb_put(inst->skb, nla_total_size(data_len));
648 nla->nla_type = NFULA_PAYLOAD;
649 nla->nla_len = size;
650
651 if (skb_copy_bits(skb, 0, nla_data(nla), data_len))
652 BUG();
653 }
654
655 nlh->nlmsg_len = inst->skb->tail - old_tail;
656 return 0;
657
658nla_put_failure:
659 PRINTR(KERN_ERR "nfnetlink_log: error creating log nlmsg\n");
660 return -1;
661}
662
663static const struct nf_loginfo default_loginfo = {
664 .type = NF_LOG_TYPE_ULOG,
665 .u = {
666 .ulog = {
667 .copy_len = 0xffff,
668 .group = 0,
669 .qthreshold = 1,
670 },
671 },
672};
673
674
675static void
676nfulnl_log_packet(struct net *net,
677 u_int8_t pf,
678 unsigned int hooknum,
679 const struct sk_buff *skb,
680 const struct net_device *in,
681 const struct net_device *out,
682 const struct nf_loginfo *li_user,
683 const char *prefix)
684{
685 size_t size;
686 unsigned int data_len;
687 struct nfulnl_instance *inst;
688 const struct nf_loginfo *li;
689 unsigned int qthreshold;
690 unsigned int plen = 0;
691 struct nfnl_log_net *log = nfnl_log_pernet(net);
692 const struct nfnl_ct_hook *nfnl_ct = NULL;
693 struct nf_conn *ct = NULL;
694 enum ip_conntrack_info ctinfo;
695
696 if (li_user && li_user->type == NF_LOG_TYPE_ULOG)
697 li = li_user;
698 else
699 li = &default_loginfo;
700
701 inst = instance_lookup_get(log, li->u.ulog.group);
702 if (!inst)
703 return;
704
705 if (prefix)
706 plen = strlen(prefix) + 1;
707
708
709
710
711 size = nlmsg_total_size(sizeof(struct nfgenmsg))
712 + nla_total_size(sizeof(struct nfulnl_msg_packet_hdr))
713 + nla_total_size(sizeof(u_int32_t))
714 + nla_total_size(sizeof(u_int32_t))
715#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
716 + nla_total_size(sizeof(u_int32_t))
717 + nla_total_size(sizeof(u_int32_t))
718#endif
719 + nla_total_size(sizeof(u_int32_t))
720 + nla_total_size(sizeof(u_int32_t))
721 + nla_total_size(sizeof(u_int32_t))
722 + nla_total_size(plen)
723 + nla_total_size(sizeof(struct nfulnl_msg_packet_hw))
724 + nla_total_size(sizeof(struct nfulnl_msg_packet_timestamp))
725 + nla_total_size(sizeof(struct nfgenmsg));
726
727 if (in && skb_mac_header_was_set(skb)) {
728 size += nla_total_size(skb->dev->hard_header_len)
729 + nla_total_size(sizeof(u_int16_t))
730 + nla_total_size(sizeof(u_int16_t));
731 }
732
733 spin_lock_bh(&inst->lock);
734
735 if (inst->flags & NFULNL_CFG_F_SEQ)
736 size += nla_total_size(sizeof(u_int32_t));
737 if (inst->flags & NFULNL_CFG_F_SEQ_GLOBAL)
738 size += nla_total_size(sizeof(u_int32_t));
739#if IS_ENABLED(CONFIG_NF_CONNTRACK)
740 if (inst->flags & NFULNL_CFG_F_CONNTRACK) {
741 nfnl_ct = rcu_dereference(nfnl_ct_hook);
742 if (nfnl_ct != NULL) {
743 ct = nf_ct_get(skb, &ctinfo);
744 if (ct != NULL)
745 size += nfnl_ct->build_size(ct);
746 }
747 }
748#endif
749 if (pf == NFPROTO_NETDEV || pf == NFPROTO_BRIDGE)
750 size += nfulnl_get_bridge_size(skb);
751
752 qthreshold = inst->qthreshold;
753
754 if (li->u.ulog.qthreshold)
755 if (qthreshold > li->u.ulog.qthreshold)
756 qthreshold = li->u.ulog.qthreshold;
757
758
759 switch (inst->copy_mode) {
760 case NFULNL_COPY_META:
761 case NFULNL_COPY_NONE:
762 data_len = 0;
763 break;
764
765 case NFULNL_COPY_PACKET:
766 data_len = inst->copy_range;
767 if ((li->u.ulog.flags & NF_LOG_F_COPY_LEN) &&
768 (li->u.ulog.copy_len < data_len))
769 data_len = li->u.ulog.copy_len;
770
771 if (data_len > skb->len)
772 data_len = skb->len;
773
774 size += nla_total_size(data_len);
775 break;
776
777 case NFULNL_COPY_DISABLED:
778 default:
779 goto unlock_and_release;
780 }
781
782 if (inst->skb && size > skb_tailroom(inst->skb)) {
783
784
785 __nfulnl_flush(inst);
786 }
787
788 if (!inst->skb) {
789 inst->skb = nfulnl_alloc_skb(net, inst->peer_portid,
790 inst->nlbufsiz, size);
791 if (!inst->skb)
792 goto alloc_failure;
793 }
794
795 inst->qlen++;
796
797 __build_packet_message(log, inst, skb, data_len, pf,
798 hooknum, in, out, prefix, plen,
799 nfnl_ct, ct, ctinfo);
800
801 if (inst->qlen >= qthreshold)
802 __nfulnl_flush(inst);
803
804
805 else if (!timer_pending(&inst->timer)) {
806 instance_get(inst);
807 inst->timer.expires = jiffies + (inst->flushtimeout*HZ/100);
808 add_timer(&inst->timer);
809 }
810
811unlock_and_release:
812 spin_unlock_bh(&inst->lock);
813 instance_put(inst);
814 return;
815
816alloc_failure:
817
818 goto unlock_and_release;
819}
820
821static int
822nfulnl_rcv_nl_event(struct notifier_block *this,
823 unsigned long event, void *ptr)
824{
825 struct netlink_notify *n = ptr;
826 struct nfnl_log_net *log = nfnl_log_pernet(n->net);
827
828 if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
829 int i;
830
831
832 spin_lock_bh(&log->instances_lock);
833 for (i = 0; i < INSTANCE_BUCKETS; i++) {
834 struct hlist_node *t2;
835 struct nfulnl_instance *inst;
836 struct hlist_head *head = &log->instance_table[i];
837
838 hlist_for_each_entry_safe(inst, t2, head, hlist) {
839 if (n->portid == inst->peer_portid)
840 __instance_destroy(inst);
841 }
842 }
843 spin_unlock_bh(&log->instances_lock);
844 }
845 return NOTIFY_DONE;
846}
847
848static struct notifier_block nfulnl_rtnl_notifier = {
849 .notifier_call = nfulnl_rcv_nl_event,
850};
851
852static int nfulnl_recv_unsupp(struct sk_buff *skb, const struct nfnl_info *info,
853 const struct nlattr * const nfula[])
854{
855 return -ENOTSUPP;
856}
857
858static struct nf_logger nfulnl_logger __read_mostly = {
859 .name = "nfnetlink_log",
860 .type = NF_LOG_TYPE_ULOG,
861 .logfn = nfulnl_log_packet,
862 .me = THIS_MODULE,
863};
864
865static const struct nla_policy nfula_cfg_policy[NFULA_CFG_MAX+1] = {
866 [NFULA_CFG_CMD] = { .len = sizeof(struct nfulnl_msg_config_cmd) },
867 [NFULA_CFG_MODE] = { .len = sizeof(struct nfulnl_msg_config_mode) },
868 [NFULA_CFG_TIMEOUT] = { .type = NLA_U32 },
869 [NFULA_CFG_QTHRESH] = { .type = NLA_U32 },
870 [NFULA_CFG_NLBUFSIZ] = { .type = NLA_U32 },
871 [NFULA_CFG_FLAGS] = { .type = NLA_U16 },
872};
873
874static int nfulnl_recv_config(struct sk_buff *skb, const struct nfnl_info *info,
875 const struct nlattr * const nfula[])
876{
877 struct nfnl_log_net *log = nfnl_log_pernet(info->net);
878 u_int16_t group_num = ntohs(info->nfmsg->res_id);
879 struct nfulnl_msg_config_cmd *cmd = NULL;
880 struct nfulnl_instance *inst;
881 u16 flags = 0;
882 int ret = 0;
883
884 if (nfula[NFULA_CFG_CMD]) {
885 u_int8_t pf = info->nfmsg->nfgen_family;
886 cmd = nla_data(nfula[NFULA_CFG_CMD]);
887
888
889 switch (cmd->command) {
890 case NFULNL_CFG_CMD_PF_BIND:
891 return nf_log_bind_pf(info->net, pf, &nfulnl_logger);
892 case NFULNL_CFG_CMD_PF_UNBIND:
893 nf_log_unbind_pf(info->net, pf);
894 return 0;
895 }
896 }
897
898 inst = instance_lookup_get(log, group_num);
899 if (inst && inst->peer_portid != NETLINK_CB(skb).portid) {
900 ret = -EPERM;
901 goto out_put;
902 }
903
904
905
906
907 if (nfula[NFULA_CFG_FLAGS]) {
908 flags = ntohs(nla_get_be16(nfula[NFULA_CFG_FLAGS]));
909
910 if ((flags & NFULNL_CFG_F_CONNTRACK) &&
911 !rcu_access_pointer(nfnl_ct_hook)) {
912#ifdef CONFIG_MODULES
913 nfnl_unlock(NFNL_SUBSYS_ULOG);
914 request_module("ip_conntrack_netlink");
915 nfnl_lock(NFNL_SUBSYS_ULOG);
916 if (rcu_access_pointer(nfnl_ct_hook)) {
917 ret = -EAGAIN;
918 goto out_put;
919 }
920#endif
921 ret = -EOPNOTSUPP;
922 goto out_put;
923 }
924 }
925
926 if (cmd != NULL) {
927 switch (cmd->command) {
928 case NFULNL_CFG_CMD_BIND:
929 if (inst) {
930 ret = -EBUSY;
931 goto out_put;
932 }
933
934 inst = instance_create(info->net, group_num,
935 NETLINK_CB(skb).portid,
936 sk_user_ns(NETLINK_CB(skb).sk));
937 if (IS_ERR(inst)) {
938 ret = PTR_ERR(inst);
939 goto out;
940 }
941 break;
942 case NFULNL_CFG_CMD_UNBIND:
943 if (!inst) {
944 ret = -ENODEV;
945 goto out;
946 }
947
948 instance_destroy(log, inst);
949 goto out_put;
950 default:
951 ret = -ENOTSUPP;
952 goto out_put;
953 }
954 } else if (!inst) {
955 ret = -ENODEV;
956 goto out;
957 }
958
959 if (nfula[NFULA_CFG_MODE]) {
960 struct nfulnl_msg_config_mode *params =
961 nla_data(nfula[NFULA_CFG_MODE]);
962
963 nfulnl_set_mode(inst, params->copy_mode,
964 ntohl(params->copy_range));
965 }
966
967 if (nfula[NFULA_CFG_TIMEOUT]) {
968 __be32 timeout = nla_get_be32(nfula[NFULA_CFG_TIMEOUT]);
969
970 nfulnl_set_timeout(inst, ntohl(timeout));
971 }
972
973 if (nfula[NFULA_CFG_NLBUFSIZ]) {
974 __be32 nlbufsiz = nla_get_be32(nfula[NFULA_CFG_NLBUFSIZ]);
975
976 nfulnl_set_nlbufsiz(inst, ntohl(nlbufsiz));
977 }
978
979 if (nfula[NFULA_CFG_QTHRESH]) {
980 __be32 qthresh = nla_get_be32(nfula[NFULA_CFG_QTHRESH]);
981
982 nfulnl_set_qthresh(inst, ntohl(qthresh));
983 }
984
985 if (nfula[NFULA_CFG_FLAGS])
986 nfulnl_set_flags(inst, flags);
987
988out_put:
989 instance_put(inst);
990out:
991 return ret;
992}
993
994static const struct nfnl_callback nfulnl_cb[NFULNL_MSG_MAX] = {
995 [NFULNL_MSG_PACKET] = {
996 .call = nfulnl_recv_unsupp,
997 .type = NFNL_CB_MUTEX,
998 .attr_count = NFULA_MAX,
999 },
1000 [NFULNL_MSG_CONFIG] = {
1001 .call = nfulnl_recv_config,
1002 .type = NFNL_CB_MUTEX,
1003 .attr_count = NFULA_CFG_MAX,
1004 .policy = nfula_cfg_policy
1005 },
1006};
1007
1008static const struct nfnetlink_subsystem nfulnl_subsys = {
1009 .name = "log",
1010 .subsys_id = NFNL_SUBSYS_ULOG,
1011 .cb_count = NFULNL_MSG_MAX,
1012 .cb = nfulnl_cb,
1013};
1014
1015#ifdef CONFIG_PROC_FS
1016struct iter_state {
1017 struct seq_net_private p;
1018 unsigned int bucket;
1019};
1020
1021static struct hlist_node *get_first(struct net *net, struct iter_state *st)
1022{
1023 struct nfnl_log_net *log;
1024 if (!st)
1025 return NULL;
1026
1027 log = nfnl_log_pernet(net);
1028
1029 for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
1030 struct hlist_head *head = &log->instance_table[st->bucket];
1031
1032 if (!hlist_empty(head))
1033 return rcu_dereference_bh(hlist_first_rcu(head));
1034 }
1035 return NULL;
1036}
1037
1038static struct hlist_node *get_next(struct net *net, struct iter_state *st,
1039 struct hlist_node *h)
1040{
1041 h = rcu_dereference_bh(hlist_next_rcu(h));
1042 while (!h) {
1043 struct nfnl_log_net *log;
1044 struct hlist_head *head;
1045
1046 if (++st->bucket >= INSTANCE_BUCKETS)
1047 return NULL;
1048
1049 log = nfnl_log_pernet(net);
1050 head = &log->instance_table[st->bucket];
1051 h = rcu_dereference_bh(hlist_first_rcu(head));
1052 }
1053 return h;
1054}
1055
1056static struct hlist_node *get_idx(struct net *net, struct iter_state *st,
1057 loff_t pos)
1058{
1059 struct hlist_node *head;
1060 head = get_first(net, st);
1061
1062 if (head)
1063 while (pos && (head = get_next(net, st, head)))
1064 pos--;
1065 return pos ? NULL : head;
1066}
1067
1068static void *seq_start(struct seq_file *s, loff_t *pos)
1069 __acquires(rcu_bh)
1070{
1071 rcu_read_lock_bh();
1072 return get_idx(seq_file_net(s), s->private, *pos);
1073}
1074
1075static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
1076{
1077 (*pos)++;
1078 return get_next(seq_file_net(s), s->private, v);
1079}
1080
1081static void seq_stop(struct seq_file *s, void *v)
1082 __releases(rcu_bh)
1083{
1084 rcu_read_unlock_bh();
1085}
1086
1087static int seq_show(struct seq_file *s, void *v)
1088{
1089 const struct nfulnl_instance *inst = v;
1090
1091 seq_printf(s, "%5u %6u %5u %1u %5u %6u %2u\n",
1092 inst->group_num,
1093 inst->peer_portid, inst->qlen,
1094 inst->copy_mode, inst->copy_range,
1095 inst->flushtimeout, refcount_read(&inst->use));
1096
1097 return 0;
1098}
1099
1100static const struct seq_operations nful_seq_ops = {
1101 .start = seq_start,
1102 .next = seq_next,
1103 .stop = seq_stop,
1104 .show = seq_show,
1105};
1106#endif
1107
1108static int __net_init nfnl_log_net_init(struct net *net)
1109{
1110 unsigned int i;
1111 struct nfnl_log_net *log = nfnl_log_pernet(net);
1112#ifdef CONFIG_PROC_FS
1113 struct proc_dir_entry *proc;
1114 kuid_t root_uid;
1115 kgid_t root_gid;
1116#endif
1117
1118 for (i = 0; i < INSTANCE_BUCKETS; i++)
1119 INIT_HLIST_HEAD(&log->instance_table[i]);
1120 spin_lock_init(&log->instances_lock);
1121
1122#ifdef CONFIG_PROC_FS
1123 proc = proc_create_net("nfnetlink_log", 0440, net->nf.proc_netfilter,
1124 &nful_seq_ops, sizeof(struct iter_state));
1125 if (!proc)
1126 return -ENOMEM;
1127
1128 root_uid = make_kuid(net->user_ns, 0);
1129 root_gid = make_kgid(net->user_ns, 0);
1130 if (uid_valid(root_uid) && gid_valid(root_gid))
1131 proc_set_user(proc, root_uid, root_gid);
1132#endif
1133 return 0;
1134}
1135
1136static void __net_exit nfnl_log_net_exit(struct net *net)
1137{
1138 struct nfnl_log_net *log = nfnl_log_pernet(net);
1139 unsigned int i;
1140
1141#ifdef CONFIG_PROC_FS
1142 remove_proc_entry("nfnetlink_log", net->nf.proc_netfilter);
1143#endif
1144 nf_log_unset(net, &nfulnl_logger);
1145 for (i = 0; i < INSTANCE_BUCKETS; i++)
1146 WARN_ON_ONCE(!hlist_empty(&log->instance_table[i]));
1147}
1148
1149static struct pernet_operations nfnl_log_net_ops = {
1150 .init = nfnl_log_net_init,
1151 .exit = nfnl_log_net_exit,
1152 .id = &nfnl_log_net_id,
1153 .size = sizeof(struct nfnl_log_net),
1154};
1155
1156static int __init nfnetlink_log_init(void)
1157{
1158 int status;
1159
1160 status = register_pernet_subsys(&nfnl_log_net_ops);
1161 if (status < 0) {
1162 pr_err("failed to register pernet ops\n");
1163 goto out;
1164 }
1165
1166 netlink_register_notifier(&nfulnl_rtnl_notifier);
1167 status = nfnetlink_subsys_register(&nfulnl_subsys);
1168 if (status < 0) {
1169 pr_err("failed to create netlink socket\n");
1170 goto cleanup_netlink_notifier;
1171 }
1172
1173 status = nf_log_register(NFPROTO_UNSPEC, &nfulnl_logger);
1174 if (status < 0) {
1175 pr_err("failed to register logger\n");
1176 goto cleanup_subsys;
1177 }
1178
1179 return status;
1180
1181cleanup_subsys:
1182 nfnetlink_subsys_unregister(&nfulnl_subsys);
1183cleanup_netlink_notifier:
1184 netlink_unregister_notifier(&nfulnl_rtnl_notifier);
1185 unregister_pernet_subsys(&nfnl_log_net_ops);
1186out:
1187 return status;
1188}
1189
1190static void __exit nfnetlink_log_fini(void)
1191{
1192 nfnetlink_subsys_unregister(&nfulnl_subsys);
1193 netlink_unregister_notifier(&nfulnl_rtnl_notifier);
1194 unregister_pernet_subsys(&nfnl_log_net_ops);
1195 nf_log_unregister(&nfulnl_logger);
1196}
1197
1198MODULE_DESCRIPTION("netfilter userspace logging");
1199MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
1200MODULE_LICENSE("GPL");
1201MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_ULOG);
1202MODULE_ALIAS_NF_LOGGER(AF_INET, 1);
1203MODULE_ALIAS_NF_LOGGER(AF_INET6, 1);
1204MODULE_ALIAS_NF_LOGGER(AF_BRIDGE, 1);
1205MODULE_ALIAS_NF_LOGGER(3, 1);
1206MODULE_ALIAS_NF_LOGGER(5, 1);
1207
1208module_init(nfnetlink_log_init);
1209module_exit(nfnetlink_log_fini);
1210
