1
2
3
4
5
6
7
8
9
10
11
12
13
14
15#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16
17#include <linux/types.h>
18#include <linux/netfilter.h>
19#include <linux/module.h>
20#include <linux/sched.h>
21#include <linux/skbuff.h>
22#include <linux/proc_fs.h>
23#include <linux/vmalloc.h>
24#include <linux/stddef.h>
25#include <linux/slab.h>
26#include <linux/random.h>
27#include <linux/jhash.h>
28#include <linux/err.h>
29#include <linux/percpu.h>
30#include <linux/moduleparam.h>
31#include <linux/notifier.h>
32#include <linux/kernel.h>
33#include <linux/netdevice.h>
34#include <linux/socket.h>
35#include <linux/mm.h>
36#include <linux/nsproxy.h>
37#include <linux/rculist_nulls.h>
38
39#include <net/netfilter/nf_conntrack.h>
40#include <net/netfilter/nf_conntrack_l3proto.h>
41#include <net/netfilter/nf_conntrack_l4proto.h>
42#include <net/netfilter/nf_conntrack_expect.h>
43#include <net/netfilter/nf_conntrack_helper.h>
44#include <net/netfilter/nf_conntrack_seqadj.h>
45#include <net/netfilter/nf_conntrack_core.h>
46#include <net/netfilter/nf_conntrack_extend.h>
47#include <net/netfilter/nf_conntrack_acct.h>
48#include <net/netfilter/nf_conntrack_ecache.h>
49#include <net/netfilter/nf_conntrack_zones.h>
50#include <net/netfilter/nf_conntrack_timestamp.h>
51#include <net/netfilter/nf_conntrack_timeout.h>
52#include <net/netfilter/nf_conntrack_labels.h>
53#include <net/netfilter/nf_conntrack_synproxy.h>
54#include <net/netfilter/nf_nat.h>
55#include <net/netfilter/nf_nat_core.h>
56#include <net/netfilter/nf_nat_helper.h>
57#include <net/netns/hash.h>
58
59#define NF_CONNTRACK_VERSION "0.5.0"
60
61int (*nfnetlink_parse_nat_setup_hook)(struct nf_conn *ct,
62 enum nf_nat_manip_type manip,
63 const struct nlattr *attr) __read_mostly;
64EXPORT_SYMBOL_GPL(nfnetlink_parse_nat_setup_hook);
65
66__cacheline_aligned_in_smp spinlock_t nf_conntrack_locks[CONNTRACK_LOCKS];
67EXPORT_SYMBOL_GPL(nf_conntrack_locks);
68
69__cacheline_aligned_in_smp DEFINE_SPINLOCK(nf_conntrack_expect_lock);
70EXPORT_SYMBOL_GPL(nf_conntrack_expect_lock);
71
72struct hlist_nulls_head *nf_conntrack_hash __read_mostly;
73EXPORT_SYMBOL_GPL(nf_conntrack_hash);
74
75static __read_mostly struct kmem_cache *nf_conntrack_cachep;
76static __read_mostly spinlock_t nf_conntrack_locks_all_lock;
77static __read_mostly seqcount_t nf_conntrack_generation;
78static __read_mostly DEFINE_SPINLOCK(nf_conntrack_locks_all_lock);
79static __read_mostly bool nf_conntrack_locks_all;
80
81void nf_conntrack_lock(spinlock_t *lock) __acquires(lock)
82{
83 spin_lock(lock);
84 while (unlikely(nf_conntrack_locks_all)) {
85 spin_unlock(lock);
86
87
88
89
90
91
92 smp_rmb();
93 spin_unlock_wait(&nf_conntrack_locks_all_lock);
94 spin_lock(lock);
95 }
96}
97EXPORT_SYMBOL_GPL(nf_conntrack_lock);
98
99static void nf_conntrack_double_unlock(unsigned int h1, unsigned int h2)
100{
101 h1 %= CONNTRACK_LOCKS;
102 h2 %= CONNTRACK_LOCKS;
103 spin_unlock(&nf_conntrack_locks[h1]);
104 if (h1 != h2)
105 spin_unlock(&nf_conntrack_locks[h2]);
106}
107
108
109static bool nf_conntrack_double_lock(struct net *net, unsigned int h1,
110 unsigned int h2, unsigned int sequence)
111{
112 h1 %= CONNTRACK_LOCKS;
113 h2 %= CONNTRACK_LOCKS;
114 if (h1 <= h2) {
115 nf_conntrack_lock(&nf_conntrack_locks[h1]);
116 if (h1 != h2)
117 spin_lock_nested(&nf_conntrack_locks[h2],
118 SINGLE_DEPTH_NESTING);
119 } else {
120 nf_conntrack_lock(&nf_conntrack_locks[h2]);
121 spin_lock_nested(&nf_conntrack_locks[h1],
122 SINGLE_DEPTH_NESTING);
123 }
124 if (read_seqcount_retry(&nf_conntrack_generation, sequence)) {
125 nf_conntrack_double_unlock(h1, h2);
126 return true;
127 }
128 return false;
129}
130
131static void nf_conntrack_all_lock(void)
132{
133 int i;
134
135 spin_lock(&nf_conntrack_locks_all_lock);
136 nf_conntrack_locks_all = true;
137
138
139
140
141
142
143
144 smp_mb();
145
146 for (i = 0; i < CONNTRACK_LOCKS; i++) {
147 spin_unlock_wait(&nf_conntrack_locks[i]);
148 }
149}
150
151static void nf_conntrack_all_unlock(void)
152{
153
154
155
156
157
158
159 smp_store_release(&nf_conntrack_locks_all, false);
160 spin_unlock(&nf_conntrack_locks_all_lock);
161}
162
163unsigned int nf_conntrack_htable_size __read_mostly;
164EXPORT_SYMBOL_GPL(nf_conntrack_htable_size);
165
166unsigned int nf_conntrack_max __read_mostly;
167EXPORT_SYMBOL_GPL(nf_conntrack_max);
168
169DEFINE_PER_CPU(struct nf_conn, nf_conntrack_untracked);
170EXPORT_PER_CPU_SYMBOL(nf_conntrack_untracked);
171
172static unsigned int nf_conntrack_hash_rnd __read_mostly;
173
174static u32 hash_conntrack_raw(const struct nf_conntrack_tuple *tuple,
175 const struct net *net)
176{
177 unsigned int n;
178 u32 seed;
179
180 get_random_once(&nf_conntrack_hash_rnd, sizeof(nf_conntrack_hash_rnd));
181
182
183
184
185
186 seed = nf_conntrack_hash_rnd ^ net_hash_mix(net);
187 n = (sizeof(tuple->src) + sizeof(tuple->dst.u3)) / sizeof(u32);
188 return jhash2((u32 *)tuple, n, seed ^
189 (((__force __u16)tuple->dst.u.all << 16) |
190 tuple->dst.protonum));
191}
192
193static u32 scale_hash(u32 hash)
194{
195 return reciprocal_scale(hash, nf_conntrack_htable_size);
196}
197
198static u32 __hash_conntrack(const struct net *net,
199 const struct nf_conntrack_tuple *tuple,
200 unsigned int size)
201{
202 return reciprocal_scale(hash_conntrack_raw(tuple, net), size);
203}
204
205static u32 hash_conntrack(const struct net *net,
206 const struct nf_conntrack_tuple *tuple)
207{
208 return scale_hash(hash_conntrack_raw(tuple, net));
209}
210
211bool
212nf_ct_get_tuple(const struct sk_buff *skb,
213 unsigned int nhoff,
214 unsigned int dataoff,
215 u_int16_t l3num,
216 u_int8_t protonum,
217 struct net *net,
218 struct nf_conntrack_tuple *tuple,
219 const struct nf_conntrack_l3proto *l3proto,
220 const struct nf_conntrack_l4proto *l4proto)
221{
222 memset(tuple, 0, sizeof(*tuple));
223
224 tuple->src.l3num = l3num;
225 if (l3proto->pkt_to_tuple(skb, nhoff, tuple) == 0)
226 return false;
227
228 tuple->dst.protonum = protonum;
229 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
230
231 return l4proto->pkt_to_tuple(skb, dataoff, net, tuple);
232}
233EXPORT_SYMBOL_GPL(nf_ct_get_tuple);
234
235bool nf_ct_get_tuplepr(const struct sk_buff *skb, unsigned int nhoff,
236 u_int16_t l3num,
237 struct net *net, struct nf_conntrack_tuple *tuple)
238{
239 struct nf_conntrack_l3proto *l3proto;
240 struct nf_conntrack_l4proto *l4proto;
241 unsigned int protoff;
242 u_int8_t protonum;
243 int ret;
244
245 rcu_read_lock();
246
247 l3proto = __nf_ct_l3proto_find(l3num);
248 ret = l3proto->get_l4proto(skb, nhoff, &protoff, &protonum);
249 if (ret != NF_ACCEPT) {
250 rcu_read_unlock();
251 return false;
252 }
253
254 l4proto = __nf_ct_l4proto_find(l3num, protonum);
255
256 ret = nf_ct_get_tuple(skb, nhoff, protoff, l3num, protonum, net, tuple,
257 l3proto, l4proto);
258
259 rcu_read_unlock();
260 return ret;
261}
262EXPORT_SYMBOL_GPL(nf_ct_get_tuplepr);
263
264bool
265nf_ct_invert_tuple(struct nf_conntrack_tuple *inverse,
266 const struct nf_conntrack_tuple *orig,
267 const struct nf_conntrack_l3proto *l3proto,
268 const struct nf_conntrack_l4proto *l4proto)
269{
270 memset(inverse, 0, sizeof(*inverse));
271
272 inverse->src.l3num = orig->src.l3num;
273 if (l3proto->invert_tuple(inverse, orig) == 0)
274 return false;
275
276 inverse->dst.dir = !orig->dst.dir;
277
278 inverse->dst.protonum = orig->dst.protonum;
279 return l4proto->invert_tuple(inverse, orig);
280}
281EXPORT_SYMBOL_GPL(nf_ct_invert_tuple);
282
283static void
284clean_from_lists(struct nf_conn *ct)
285{
286 pr_debug("clean_from_lists(%p)\n", ct);
287 hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode);
288 hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_REPLY].hnnode);
289
290
291 nf_ct_remove_expectations(ct);
292}
293
294
295static void nf_ct_add_to_dying_list(struct nf_conn *ct)
296{
297 struct ct_pcpu *pcpu;
298
299
300 ct->cpu = smp_processor_id();
301 pcpu = per_cpu_ptr(nf_ct_net(ct)->ct.pcpu_lists, ct->cpu);
302
303 spin_lock(&pcpu->lock);
304 hlist_nulls_add_head(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode,
305 &pcpu->dying);
306 spin_unlock(&pcpu->lock);
307}
308
309
310static void nf_ct_add_to_unconfirmed_list(struct nf_conn *ct)
311{
312 struct ct_pcpu *pcpu;
313
314
315 ct->cpu = smp_processor_id();
316 pcpu = per_cpu_ptr(nf_ct_net(ct)->ct.pcpu_lists, ct->cpu);
317
318 spin_lock(&pcpu->lock);
319 hlist_nulls_add_head(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode,
320 &pcpu->unconfirmed);
321 spin_unlock(&pcpu->lock);
322}
323
324
325static void nf_ct_del_from_dying_or_unconfirmed_list(struct nf_conn *ct)
326{
327 struct ct_pcpu *pcpu;
328
329
330 pcpu = per_cpu_ptr(nf_ct_net(ct)->ct.pcpu_lists, ct->cpu);
331
332 spin_lock(&pcpu->lock);
333 BUG_ON(hlist_nulls_unhashed(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode));
334 hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode);
335 spin_unlock(&pcpu->lock);
336}
337
338
339struct nf_conn *nf_ct_tmpl_alloc(struct net *net,
340 const struct nf_conntrack_zone *zone,
341 gfp_t flags)
342{
343 struct nf_conn *tmpl;
344
345 tmpl = kzalloc(sizeof(*tmpl), flags);
346 if (tmpl == NULL)
347 return NULL;
348
349 tmpl->status = IPS_TEMPLATE;
350 write_pnet(&tmpl->ct_net, net);
351 nf_ct_zone_add(tmpl, zone);
352 atomic_set(&tmpl->ct_general.use, 0);
353
354 return tmpl;
355}
356EXPORT_SYMBOL_GPL(nf_ct_tmpl_alloc);
357
358void nf_ct_tmpl_free(struct nf_conn *tmpl)
359{
360 nf_ct_ext_destroy(tmpl);
361 nf_ct_ext_free(tmpl);
362 kfree(tmpl);
363}
364EXPORT_SYMBOL_GPL(nf_ct_tmpl_free);
365
366static void
367destroy_conntrack(struct nf_conntrack *nfct)
368{
369 struct nf_conn *ct = (struct nf_conn *)nfct;
370 struct net *net = nf_ct_net(ct);
371 struct nf_conntrack_l4proto *l4proto;
372
373 pr_debug("destroy_conntrack(%p)\n", ct);
374 NF_CT_ASSERT(atomic_read(&nfct->use) == 0);
375 NF_CT_ASSERT(!timer_pending(&ct->timeout));
376
377 if (unlikely(nf_ct_is_template(ct))) {
378 nf_ct_tmpl_free(ct);
379 return;
380 }
381 rcu_read_lock();
382 l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct));
383 if (l4proto->destroy)
384 l4proto->destroy(ct);
385
386 rcu_read_unlock();
387
388 local_bh_disable();
389
390
391
392
393
394 nf_ct_remove_expectations(ct);
395
396 nf_ct_del_from_dying_or_unconfirmed_list(ct);
397
398 NF_CT_STAT_INC(net, delete);
399 local_bh_enable();
400
401 if (ct->master)
402 nf_ct_put(ct->master);
403
404 pr_debug("destroy_conntrack: returning ct=%p to slab\n", ct);
405 nf_conntrack_free(ct);
406}
407
408static void nf_ct_delete_from_lists(struct nf_conn *ct)
409{
410 struct net *net = nf_ct_net(ct);
411 unsigned int hash, reply_hash;
412 unsigned int sequence;
413
414 nf_ct_helper_destroy(ct);
415
416 local_bh_disable();
417 do {
418 sequence = read_seqcount_begin(&nf_conntrack_generation);
419 hash = hash_conntrack(net,
420 &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
421 reply_hash = hash_conntrack(net,
422 &ct->tuplehash[IP_CT_DIR_REPLY].tuple);
423 } while (nf_conntrack_double_lock(net, hash, reply_hash, sequence));
424
425 clean_from_lists(ct);
426 nf_conntrack_double_unlock(hash, reply_hash);
427
428 nf_ct_add_to_dying_list(ct);
429
430 NF_CT_STAT_INC(net, delete_list);
431 local_bh_enable();
432}
433
434bool nf_ct_delete(struct nf_conn *ct, u32 portid, int report)
435{
436 struct nf_conn_tstamp *tstamp;
437
438 tstamp = nf_conn_tstamp_find(ct);
439 if (tstamp && tstamp->stop == 0)
440 tstamp->stop = ktime_get_real_ns();
441
442 if (nf_ct_is_dying(ct))
443 goto delete;
444
445 if (nf_conntrack_event_report(IPCT_DESTROY, ct,
446 portid, report) < 0) {
447
448 nf_ct_delete_from_lists(ct);
449 nf_conntrack_ecache_delayed_work(nf_ct_net(ct));
450 return false;
451 }
452
453 nf_conntrack_ecache_work(nf_ct_net(ct));
454 set_bit(IPS_DYING_BIT, &ct->status);
455 delete:
456 nf_ct_delete_from_lists(ct);
457 nf_ct_put(ct);
458 return true;
459}
460EXPORT_SYMBOL_GPL(nf_ct_delete);
461
462static void death_by_timeout(unsigned long ul_conntrack)
463{
464 nf_ct_delete((struct nf_conn *)ul_conntrack, 0, 0);
465}
466
467static inline bool
468nf_ct_key_equal(struct nf_conntrack_tuple_hash *h,
469 const struct nf_conntrack_tuple *tuple,
470 const struct nf_conntrack_zone *zone,
471 const struct net *net)
472{
473 struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
474
475
476
477
478 return nf_ct_tuple_equal(tuple, &h->tuple) &&
479 nf_ct_zone_equal(ct, zone, NF_CT_DIRECTION(h)) &&
480 nf_ct_is_confirmed(ct) &&
481 net_eq(net, nf_ct_net(ct));
482}
483
484
485void nf_conntrack_get_ht(struct hlist_nulls_head **hash, unsigned int *hsize)
486{
487 struct hlist_nulls_head *hptr;
488 unsigned int sequence, hsz;
489
490 do {
491 sequence = read_seqcount_begin(&nf_conntrack_generation);
492 hsz = nf_conntrack_htable_size;
493 hptr = nf_conntrack_hash;
494 } while (read_seqcount_retry(&nf_conntrack_generation, sequence));
495
496 *hash = hptr;
497 *hsize = hsz;
498}
499EXPORT_SYMBOL_GPL(nf_conntrack_get_ht);
500
501
502
503
504
505
506static struct nf_conntrack_tuple_hash *
507____nf_conntrack_find(struct net *net, const struct nf_conntrack_zone *zone,
508 const struct nf_conntrack_tuple *tuple, u32 hash)
509{
510 struct nf_conntrack_tuple_hash *h;
511 struct hlist_nulls_head *ct_hash;
512 struct hlist_nulls_node *n;
513 unsigned int bucket, sequence;
514
515begin:
516 do {
517 sequence = read_seqcount_begin(&nf_conntrack_generation);
518 bucket = scale_hash(hash);
519 ct_hash = nf_conntrack_hash;
520 } while (read_seqcount_retry(&nf_conntrack_generation, sequence));
521
522 hlist_nulls_for_each_entry_rcu(h, n, &ct_hash[bucket], hnnode) {
523 if (nf_ct_key_equal(h, tuple, zone, net)) {
524 NF_CT_STAT_INC_ATOMIC(net, found);
525 return h;
526 }
527 NF_CT_STAT_INC_ATOMIC(net, searched);
528 }
529
530
531
532
533
534 if (get_nulls_value(n) != bucket) {
535 NF_CT_STAT_INC_ATOMIC(net, search_restart);
536 goto begin;
537 }
538
539 return NULL;
540}
541
542
543static struct nf_conntrack_tuple_hash *
544__nf_conntrack_find_get(struct net *net, const struct nf_conntrack_zone *zone,
545 const struct nf_conntrack_tuple *tuple, u32 hash)
546{
547 struct nf_conntrack_tuple_hash *h;
548 struct nf_conn *ct;
549
550 rcu_read_lock();
551begin:
552 h = ____nf_conntrack_find(net, zone, tuple, hash);
553 if (h) {
554 ct = nf_ct_tuplehash_to_ctrack(h);
555 if (unlikely(nf_ct_is_dying(ct) ||
556 !atomic_inc_not_zero(&ct->ct_general.use)))
557 h = NULL;
558 else {
559 if (unlikely(!nf_ct_key_equal(h, tuple, zone, net))) {
560 nf_ct_put(ct);
561 goto begin;
562 }
563 }
564 }
565 rcu_read_unlock();
566
567 return h;
568}
569
570struct nf_conntrack_tuple_hash *
571nf_conntrack_find_get(struct net *net, const struct nf_conntrack_zone *zone,
572 const struct nf_conntrack_tuple *tuple)
573{
574 return __nf_conntrack_find_get(net, zone, tuple,
575 hash_conntrack_raw(tuple, net));
576}
577EXPORT_SYMBOL_GPL(nf_conntrack_find_get);
578
579static void __nf_conntrack_hash_insert(struct nf_conn *ct,
580 unsigned int hash,
581 unsigned int reply_hash)
582{
583 hlist_nulls_add_head_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode,
584 &nf_conntrack_hash[hash]);
585 hlist_nulls_add_head_rcu(&ct->tuplehash[IP_CT_DIR_REPLY].hnnode,
586 &nf_conntrack_hash[reply_hash]);
587}
588
589int
590nf_conntrack_hash_check_insert(struct nf_conn *ct)
591{
592 const struct nf_conntrack_zone *zone;
593 struct net *net = nf_ct_net(ct);
594 unsigned int hash, reply_hash;
595 struct nf_conntrack_tuple_hash *h;
596 struct hlist_nulls_node *n;
597 unsigned int sequence;
598
599 zone = nf_ct_zone(ct);
600
601 local_bh_disable();
602 do {
603 sequence = read_seqcount_begin(&nf_conntrack_generation);
604 hash = hash_conntrack(net,
605 &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
606 reply_hash = hash_conntrack(net,
607 &ct->tuplehash[IP_CT_DIR_REPLY].tuple);
608 } while (nf_conntrack_double_lock(net, hash, reply_hash, sequence));
609
610
611 hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[hash], hnnode)
612 if (nf_ct_key_equal(h, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
613 zone, net))
614 goto out;
615
616 hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[reply_hash], hnnode)
617 if (nf_ct_key_equal(h, &ct->tuplehash[IP_CT_DIR_REPLY].tuple,
618 zone, net))
619 goto out;
620
621 add_timer(&ct->timeout);
622 smp_wmb();
623
624 atomic_set(&ct->ct_general.use, 2);
625 __nf_conntrack_hash_insert(ct, hash, reply_hash);
626 nf_conntrack_double_unlock(hash, reply_hash);
627 NF_CT_STAT_INC(net, insert);
628 local_bh_enable();
629 return 0;
630
631out:
632 nf_conntrack_double_unlock(hash, reply_hash);
633 NF_CT_STAT_INC(net, insert_failed);
634 local_bh_enable();
635 return -EEXIST;
636}
637EXPORT_SYMBOL_GPL(nf_conntrack_hash_check_insert);
638
639static inline void nf_ct_acct_update(struct nf_conn *ct,
640 enum ip_conntrack_info ctinfo,
641 unsigned int len)
642{
643 struct nf_conn_acct *acct;
644
645 acct = nf_conn_acct_find(ct);
646 if (acct) {
647 struct nf_conn_counter *counter = acct->counter;
648
649 atomic64_inc(&counter[CTINFO2DIR(ctinfo)].packets);
650 atomic64_add(len, &counter[CTINFO2DIR(ctinfo)].bytes);
651 }
652}
653
654static void nf_ct_acct_merge(struct nf_conn *ct, enum ip_conntrack_info ctinfo,
655 const struct nf_conn *loser_ct)
656{
657 struct nf_conn_acct *acct;
658
659 acct = nf_conn_acct_find(loser_ct);
660 if (acct) {
661 struct nf_conn_counter *counter = acct->counter;
662 unsigned int bytes;
663
664
665 bytes = atomic64_read(&counter[CTINFO2DIR(ctinfo)].bytes);
666 nf_ct_acct_update(ct, ctinfo, bytes);
667 }
668}
669
670
671static int nf_ct_resolve_clash(struct net *net, struct sk_buff *skb,
672 enum ip_conntrack_info ctinfo,
673 struct nf_conntrack_tuple_hash *h)
674{
675
676 struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
677 struct nf_conntrack_l4proto *l4proto;
678
679 l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct));
680 if (l4proto->allow_clash &&
681 !nfct_nat(ct) &&
682 !nf_ct_is_dying(ct) &&
683 atomic_inc_not_zero(&ct->ct_general.use)) {
684 nf_ct_acct_merge(ct, ctinfo, (struct nf_conn *)skb->nfct);
685 nf_conntrack_put(skb->nfct);
686
687
688
689 skb->nfct = &ct->ct_general;
690 return NF_ACCEPT;
691 }
692 NF_CT_STAT_INC(net, drop);
693 return NF_DROP;
694}
695
696
697int
698__nf_conntrack_confirm(struct sk_buff *skb)
699{
700 const struct nf_conntrack_zone *zone;
701 unsigned int hash, reply_hash;
702 struct nf_conntrack_tuple_hash *h;
703 struct nf_conn *ct;
704 struct nf_conn_help *help;
705 struct nf_conn_tstamp *tstamp;
706 struct hlist_nulls_node *n;
707 enum ip_conntrack_info ctinfo;
708 struct net *net;
709 unsigned int sequence;
710 int ret = NF_DROP;
711
712 ct = nf_ct_get(skb, &ctinfo);
713 net = nf_ct_net(ct);
714
715
716
717
718
719 if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL)
720 return NF_ACCEPT;
721
722 zone = nf_ct_zone(ct);
723 local_bh_disable();
724
725 do {
726 sequence = read_seqcount_begin(&nf_conntrack_generation);
727
728 hash = *(unsigned long *)&ct->tuplehash[IP_CT_DIR_REPLY].hnnode.pprev;
729 hash = scale_hash(hash);
730 reply_hash = hash_conntrack(net,
731 &ct->tuplehash[IP_CT_DIR_REPLY].tuple);
732
733 } while (nf_conntrack_double_lock(net, hash, reply_hash, sequence));
734
735
736
737
738
739
740
741
742
743
744 NF_CT_ASSERT(!nf_ct_is_confirmed(ct));
745 pr_debug("Confirming conntrack %p\n", ct);
746
747
748
749
750
751 nf_ct_del_from_dying_or_unconfirmed_list(ct);
752
753 if (unlikely(nf_ct_is_dying(ct))) {
754 nf_ct_add_to_dying_list(ct);
755 goto dying;
756 }
757
758
759
760
761 hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[hash], hnnode)
762 if (nf_ct_key_equal(h, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
763 zone, net))
764 goto out;
765
766 hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[reply_hash], hnnode)
767 if (nf_ct_key_equal(h, &ct->tuplehash[IP_CT_DIR_REPLY].tuple,
768 zone, net))
769 goto out;
770
771
772
773
774 ct->timeout.expires += jiffies;
775 add_timer(&ct->timeout);
776 atomic_inc(&ct->ct_general.use);
777 ct->status |= IPS_CONFIRMED;
778
779
780 tstamp = nf_conn_tstamp_find(ct);
781 if (tstamp) {
782 if (skb->tstamp.tv64 == 0)
783 __net_timestamp(skb);
784
785 tstamp->start = ktime_to_ns(skb->tstamp);
786 }
787
788
789
790
791
792 __nf_conntrack_hash_insert(ct, hash, reply_hash);
793 nf_conntrack_double_unlock(hash, reply_hash);
794 NF_CT_STAT_INC(net, insert);
795 local_bh_enable();
796
797 help = nfct_help(ct);
798 if (help && help->helper)
799 nf_conntrack_event_cache(IPCT_HELPER, ct);
800
801 nf_conntrack_event_cache(master_ct(ct) ?
802 IPCT_RELATED : IPCT_NEW, ct);
803 return NF_ACCEPT;
804
805out:
806 nf_ct_add_to_dying_list(ct);
807 ret = nf_ct_resolve_clash(net, skb, ctinfo, h);
808dying:
809 nf_conntrack_double_unlock(hash, reply_hash);
810 NF_CT_STAT_INC(net, insert_failed);
811 local_bh_enable();
812 return ret;
813}
814EXPORT_SYMBOL_GPL(__nf_conntrack_confirm);
815
816
817
818int
819nf_conntrack_tuple_taken(const struct nf_conntrack_tuple *tuple,
820 const struct nf_conn *ignored_conntrack)
821{
822 struct net *net = nf_ct_net(ignored_conntrack);
823 const struct nf_conntrack_zone *zone;
824 struct nf_conntrack_tuple_hash *h;
825 struct hlist_nulls_head *ct_hash;
826 unsigned int hash, sequence;
827 struct hlist_nulls_node *n;
828 struct nf_conn *ct;
829
830 zone = nf_ct_zone(ignored_conntrack);
831
832 rcu_read_lock();
833 do {
834 sequence = read_seqcount_begin(&nf_conntrack_generation);
835 hash = hash_conntrack(net, tuple);
836 ct_hash = nf_conntrack_hash;
837 } while (read_seqcount_retry(&nf_conntrack_generation, sequence));
838
839 hlist_nulls_for_each_entry_rcu(h, n, &ct_hash[hash], hnnode) {
840 ct = nf_ct_tuplehash_to_ctrack(h);
841 if (ct != ignored_conntrack &&
842 nf_ct_key_equal(h, tuple, zone, net)) {
843 NF_CT_STAT_INC_ATOMIC(net, found);
844 rcu_read_unlock();
845 return 1;
846 }
847 NF_CT_STAT_INC_ATOMIC(net, searched);
848 }
849 rcu_read_unlock();
850
851 return 0;
852}
853EXPORT_SYMBOL_GPL(nf_conntrack_tuple_taken);
854
855#define NF_CT_EVICTION_RANGE 8
856
857
858
859static unsigned int early_drop_list(struct net *net,
860 struct hlist_nulls_head *head)
861{
862 struct nf_conntrack_tuple_hash *h;
863 struct hlist_nulls_node *n;
864 unsigned int drops = 0;
865 struct nf_conn *tmp;
866
867 hlist_nulls_for_each_entry_rcu(h, n, head, hnnode) {
868 tmp = nf_ct_tuplehash_to_ctrack(h);
869
870 if (test_bit(IPS_ASSURED_BIT, &tmp->status) ||
871 !net_eq(nf_ct_net(tmp), net) ||
872 nf_ct_is_dying(tmp))
873 continue;
874
875 if (!atomic_inc_not_zero(&tmp->ct_general.use))
876 continue;
877
878
879
880
881
882
883
884
885 if (net_eq(nf_ct_net(tmp), net) &&
886 nf_ct_is_confirmed(tmp) &&
887 del_timer(&tmp->timeout) &&
888 nf_ct_delete(tmp, 0, 0))
889 drops++;
890
891 nf_ct_put(tmp);
892 }
893
894 return drops;
895}
896
897static noinline int early_drop(struct net *net, unsigned int _hash)
898{
899 unsigned int i;
900
901 for (i = 0; i < NF_CT_EVICTION_RANGE; i++) {
902 struct hlist_nulls_head *ct_hash;
903 unsigned hash, sequence, drops;
904
905 rcu_read_lock();
906 do {
907 sequence = read_seqcount_begin(&nf_conntrack_generation);
908 hash = scale_hash(_hash++);
909 ct_hash = nf_conntrack_hash;
910 } while (read_seqcount_retry(&nf_conntrack_generation, sequence));
911
912 drops = early_drop_list(net, &ct_hash[hash]);
913 rcu_read_unlock();
914
915 if (drops) {
916 NF_CT_STAT_ADD_ATOMIC(net, early_drop, drops);
917 return true;
918 }
919 }
920
921 return false;
922}
923
924static struct nf_conn *
925__nf_conntrack_alloc(struct net *net,
926 const struct nf_conntrack_zone *zone,
927 const struct nf_conntrack_tuple *orig,
928 const struct nf_conntrack_tuple *repl,
929 gfp_t gfp, u32 hash)
930{
931 struct nf_conn *ct;
932
933
934 atomic_inc(&net->ct.count);
935
936 if (nf_conntrack_max &&
937 unlikely(atomic_read(&net->ct.count) > nf_conntrack_max)) {
938 if (!early_drop(net, hash)) {
939 atomic_dec(&net->ct.count);
940 net_warn_ratelimited("nf_conntrack: table full, dropping packet\n");
941 return ERR_PTR(-ENOMEM);
942 }
943 }
944
945
946
947
948
949 ct = kmem_cache_alloc(nf_conntrack_cachep, gfp);
950 if (ct == NULL)
951 goto out;
952
953 spin_lock_init(&ct->lock);
954 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig;
955 ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode.pprev = NULL;
956 ct->tuplehash[IP_CT_DIR_REPLY].tuple = *repl;
957
958 *(unsigned long *)(&ct->tuplehash[IP_CT_DIR_REPLY].hnnode.pprev) = hash;
959 ct->status = 0;
960
961 setup_timer(&ct->timeout, death_by_timeout, (unsigned long)ct);
962 write_pnet(&ct->ct_net, net);
963 memset(&ct->__nfct_init_offset[0], 0,
964 offsetof(struct nf_conn, proto) -
965 offsetof(struct nf_conn, __nfct_init_offset[0]));
966
967 nf_ct_zone_add(ct, zone);
968
969
970
971
972 atomic_set(&ct->ct_general.use, 0);
973 return ct;
974out:
975 atomic_dec(&net->ct.count);
976 return ERR_PTR(-ENOMEM);
977}
978
979struct nf_conn *nf_conntrack_alloc(struct net *net,
980 const struct nf_conntrack_zone *zone,
981 const struct nf_conntrack_tuple *orig,
982 const struct nf_conntrack_tuple *repl,
983 gfp_t gfp)
984{
985 return __nf_conntrack_alloc(net, zone, orig, repl, gfp, 0);
986}
987EXPORT_SYMBOL_GPL(nf_conntrack_alloc);
988
989void nf_conntrack_free(struct nf_conn *ct)
990{
991 struct net *net = nf_ct_net(ct);
992
993
994
995
996 NF_CT_ASSERT(atomic_read(&ct->ct_general.use) == 0);
997
998 nf_ct_ext_destroy(ct);
999 nf_ct_ext_free(ct);
1000 kmem_cache_free(nf_conntrack_cachep, ct);
1001 smp_mb__before_atomic();
1002 atomic_dec(&net->ct.count);
1003}
1004EXPORT_SYMBOL_GPL(nf_conntrack_free);
1005
1006
1007
1008
1009static struct nf_conntrack_tuple_hash *
1010init_conntrack(struct net *net, struct nf_conn *tmpl,
1011 const struct nf_conntrack_tuple *tuple,
1012 struct nf_conntrack_l3proto *l3proto,
1013 struct nf_conntrack_l4proto *l4proto,
1014 struct sk_buff *skb,
1015 unsigned int dataoff, u32 hash)
1016{
1017 struct nf_conn *ct;
1018 struct nf_conn_help *help;
1019 struct nf_conntrack_tuple repl_tuple;
1020 struct nf_conntrack_ecache *ecache;
1021 struct nf_conntrack_expect *exp = NULL;
1022 const struct nf_conntrack_zone *zone;
1023 struct nf_conn_timeout *timeout_ext;
1024 struct nf_conntrack_zone tmp;
1025 unsigned int *timeouts;
1026
1027 if (!nf_ct_invert_tuple(&repl_tuple, tuple, l3proto, l4proto)) {
1028 pr_debug("Can't invert tuple.\n");
1029 return NULL;
1030 }
1031
1032 zone = nf_ct_zone_tmpl(tmpl, skb, &tmp);
1033 ct = __nf_conntrack_alloc(net, zone, tuple, &repl_tuple, GFP_ATOMIC,
1034 hash);
1035 if (IS_ERR(ct))
1036 return (struct nf_conntrack_tuple_hash *)ct;
1037
1038 if (!nf_ct_add_synproxy(ct, tmpl)) {
1039 nf_conntrack_free(ct);
1040 return ERR_PTR(-ENOMEM);
1041 }
1042
1043 timeout_ext = tmpl ? nf_ct_timeout_find(tmpl) : NULL;
1044 if (timeout_ext) {
1045 timeouts = nf_ct_timeout_data(timeout_ext);
1046 if (unlikely(!timeouts))
1047 timeouts = l4proto->get_timeouts(net);
1048 } else {
1049 timeouts = l4proto->get_timeouts(net);
1050 }
1051
1052 if (!l4proto->new(ct, skb, dataoff, timeouts)) {
1053 nf_conntrack_free(ct);
1054 pr_debug("can't track with proto module\n");
1055 return NULL;
1056 }
1057
1058 if (timeout_ext)
1059 nf_ct_timeout_ext_add(ct, rcu_dereference(timeout_ext->timeout),
1060 GFP_ATOMIC);
1061
1062 nf_ct_acct_ext_add(ct, GFP_ATOMIC);
1063 nf_ct_tstamp_ext_add(ct, GFP_ATOMIC);
1064 nf_ct_labels_ext_add(ct);
1065
1066 ecache = tmpl ? nf_ct_ecache_find(tmpl) : NULL;
1067 nf_ct_ecache_ext_add(ct, ecache ? ecache->ctmask : 0,
1068 ecache ? ecache->expmask : 0,
1069 GFP_ATOMIC);
1070
1071 local_bh_disable();
1072 if (net->ct.expect_count) {
1073 spin_lock(&nf_conntrack_expect_lock);
1074 exp = nf_ct_find_expectation(net, zone, tuple);
1075 if (exp) {
1076 pr_debug("expectation arrives ct=%p exp=%p\n",
1077 ct, exp);
1078
1079 __set_bit(IPS_EXPECTED_BIT, &ct->status);
1080
1081 ct->master = exp->master;
1082 if (exp->helper) {
1083 help = nf_ct_helper_ext_add(ct, exp->helper,
1084 GFP_ATOMIC);
1085 if (help)
1086 rcu_assign_pointer(help->helper, exp->helper);
1087 }
1088
1089#ifdef CONFIG_NF_CONNTRACK_MARK
1090 ct->mark = exp->master->mark;
1091#endif
1092#ifdef CONFIG_NF_CONNTRACK_SECMARK
1093 ct->secmark = exp->master->secmark;
1094#endif
1095 NF_CT_STAT_INC(net, expect_new);
1096 }
1097 spin_unlock(&nf_conntrack_expect_lock);
1098 }
1099 if (!exp) {
1100 __nf_ct_try_assign_helper(ct, tmpl, GFP_ATOMIC);
1101 NF_CT_STAT_INC(net, new);
1102 }
1103
1104
1105 nf_conntrack_get(&ct->ct_general);
1106 nf_ct_add_to_unconfirmed_list(ct);
1107
1108 local_bh_enable();
1109
1110 if (exp) {
1111 if (exp->expectfn)
1112 exp->expectfn(ct, exp);
1113 nf_ct_expect_put(exp);
1114 }
1115
1116 return &ct->tuplehash[IP_CT_DIR_ORIGINAL];
1117}
1118
1119
1120static inline struct nf_conn *
1121resolve_normal_ct(struct net *net, struct nf_conn *tmpl,
1122 struct sk_buff *skb,
1123 unsigned int dataoff,
1124 u_int16_t l3num,
1125 u_int8_t protonum,
1126 struct nf_conntrack_l3proto *l3proto,
1127 struct nf_conntrack_l4proto *l4proto,
1128 int *set_reply,
1129 enum ip_conntrack_info *ctinfo)
1130{
1131 const struct nf_conntrack_zone *zone;
1132 struct nf_conntrack_tuple tuple;
1133 struct nf_conntrack_tuple_hash *h;
1134 struct nf_conntrack_zone tmp;
1135 struct nf_conn *ct;
1136 u32 hash;
1137
1138 if (!nf_ct_get_tuple(skb, skb_network_offset(skb),
1139 dataoff, l3num, protonum, net, &tuple, l3proto,
1140 l4proto)) {
1141 pr_debug("Can't get tuple\n");
1142 return NULL;
1143 }
1144
1145
1146 zone = nf_ct_zone_tmpl(tmpl, skb, &tmp);
1147 hash = hash_conntrack_raw(&tuple, net);
1148 h = __nf_conntrack_find_get(net, zone, &tuple, hash);
1149 if (!h) {
1150 h = init_conntrack(net, tmpl, &tuple, l3proto, l4proto,
1151 skb, dataoff, hash);
1152 if (!h)
1153 return NULL;
1154 if (IS_ERR(h))
1155 return (void *)h;
1156 }
1157 ct = nf_ct_tuplehash_to_ctrack(h);
1158
1159
1160 if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) {
1161 *ctinfo = IP_CT_ESTABLISHED_REPLY;
1162
1163 *set_reply = 1;
1164 } else {
1165
1166 if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) {
1167 pr_debug("normal packet for %p\n", ct);
1168 *ctinfo = IP_CT_ESTABLISHED;
1169 } else if (test_bit(IPS_EXPECTED_BIT, &ct->status)) {
1170 pr_debug("related packet for %p\n", ct);
1171 *ctinfo = IP_CT_RELATED;
1172 } else {
1173 pr_debug("new packet for %p\n", ct);
1174 *ctinfo = IP_CT_NEW;
1175 }
1176 *set_reply = 0;
1177 }
1178 skb->nfct = &ct->ct_general;
1179 skb->nfctinfo = *ctinfo;
1180 return ct;
1181}
1182
1183unsigned int
1184nf_conntrack_in(struct net *net, u_int8_t pf, unsigned int hooknum,
1185 struct sk_buff *skb)
1186{
1187 struct nf_conn *ct, *tmpl = NULL;
1188 enum ip_conntrack_info ctinfo;
1189 struct nf_conntrack_l3proto *l3proto;
1190 struct nf_conntrack_l4proto *l4proto;
1191 unsigned int *timeouts;
1192 unsigned int dataoff;
1193 u_int8_t protonum;
1194 int set_reply = 0;
1195 int ret;
1196
1197 if (skb->nfct) {
1198
1199 tmpl = (struct nf_conn *)skb->nfct;
1200 if (!nf_ct_is_template(tmpl)) {
1201 NF_CT_STAT_INC_ATOMIC(net, ignore);
1202 return NF_ACCEPT;
1203 }
1204 skb->nfct = NULL;
1205 }
1206
1207
1208 l3proto = __nf_ct_l3proto_find(pf);
1209 ret = l3proto->get_l4proto(skb, skb_network_offset(skb),
1210 &dataoff, &protonum);
1211 if (ret <= 0) {
1212 pr_debug("not prepared to track yet or error occurred\n");
1213 NF_CT_STAT_INC_ATOMIC(net, error);
1214 NF_CT_STAT_INC_ATOMIC(net, invalid);
1215 ret = -ret;
1216 goto out;
1217 }
1218
1219 l4proto = __nf_ct_l4proto_find(pf, protonum);
1220
1221
1222
1223
1224 if (l4proto->error != NULL) {
1225 ret = l4proto->error(net, tmpl, skb, dataoff, &ctinfo,
1226 pf, hooknum);
1227 if (ret <= 0) {
1228 NF_CT_STAT_INC_ATOMIC(net, error);
1229 NF_CT_STAT_INC_ATOMIC(net, invalid);
1230 ret = -ret;
1231 goto out;
1232 }
1233
1234 if (skb->nfct)
1235 goto out;
1236 }
1237
1238 ct = resolve_normal_ct(net, tmpl, skb, dataoff, pf, protonum,
1239 l3proto, l4proto, &set_reply, &ctinfo);
1240 if (!ct) {
1241
1242 NF_CT_STAT_INC_ATOMIC(net, invalid);
1243 ret = NF_ACCEPT;
1244 goto out;
1245 }
1246
1247 if (IS_ERR(ct)) {
1248
1249 NF_CT_STAT_INC_ATOMIC(net, drop);
1250 ret = NF_DROP;
1251 goto out;
1252 }
1253
1254 NF_CT_ASSERT(skb->nfct);
1255
1256
1257 timeouts = nf_ct_timeout_lookup(net, ct, l4proto);
1258
1259 ret = l4proto->packet(ct, skb, dataoff, ctinfo, pf, hooknum, timeouts);
1260 if (ret <= 0) {
1261
1262
1263 pr_debug("nf_conntrack_in: Can't track with proto module\n");
1264 nf_conntrack_put(skb->nfct);
1265 skb->nfct = NULL;
1266 NF_CT_STAT_INC_ATOMIC(net, invalid);
1267 if (ret == -NF_DROP)
1268 NF_CT_STAT_INC_ATOMIC(net, drop);
1269 ret = -ret;
1270 goto out;
1271 }
1272
1273 if (set_reply && !test_and_set_bit(IPS_SEEN_REPLY_BIT, &ct->status))
1274 nf_conntrack_event_cache(IPCT_REPLY, ct);
1275out:
1276 if (tmpl) {
1277
1278
1279
1280 if (ret == NF_REPEAT)
1281 skb->nfct = (struct nf_conntrack *)tmpl;
1282 else
1283 nf_ct_put(tmpl);
1284 }
1285
1286 return ret;
1287}
1288EXPORT_SYMBOL_GPL(nf_conntrack_in);
1289
1290bool nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse,
1291 const struct nf_conntrack_tuple *orig)
1292{
1293 bool ret;
1294
1295 rcu_read_lock();
1296 ret = nf_ct_invert_tuple(inverse, orig,
1297 __nf_ct_l3proto_find(orig->src.l3num),
1298 __nf_ct_l4proto_find(orig->src.l3num,
1299 orig->dst.protonum));
1300 rcu_read_unlock();
1301 return ret;
1302}
1303EXPORT_SYMBOL_GPL(nf_ct_invert_tuplepr);
1304
1305
1306
1307void nf_conntrack_alter_reply(struct nf_conn *ct,
1308 const struct nf_conntrack_tuple *newreply)
1309{
1310 struct nf_conn_help *help = nfct_help(ct);
1311
1312
1313 NF_CT_ASSERT(!nf_ct_is_confirmed(ct));
1314
1315 pr_debug("Altering reply tuple of %p to ", ct);
1316 nf_ct_dump_tuple(newreply);
1317
1318 ct->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply;
1319 if (ct->master || (help && !hlist_empty(&help->expectations)))
1320 return;
1321
1322 rcu_read_lock();
1323 __nf_ct_try_assign_helper(ct, NULL, GFP_ATOMIC);
1324 rcu_read_unlock();
1325}
1326EXPORT_SYMBOL_GPL(nf_conntrack_alter_reply);
1327
1328
1329void __nf_ct_refresh_acct(struct nf_conn *ct,
1330 enum ip_conntrack_info ctinfo,
1331 const struct sk_buff *skb,
1332 unsigned long extra_jiffies,
1333 int do_acct)
1334{
1335 NF_CT_ASSERT(ct->timeout.data == (unsigned long)ct);
1336 NF_CT_ASSERT(skb);
1337
1338
1339 if (test_bit(IPS_FIXED_TIMEOUT_BIT, &ct->status))
1340 goto acct;
1341
1342
1343 if (!nf_ct_is_confirmed(ct)) {
1344 ct->timeout.expires = extra_jiffies;
1345 } else {
1346 unsigned long newtime = jiffies + extra_jiffies;
1347
1348
1349
1350
1351 if (newtime - ct->timeout.expires >= HZ)
1352 mod_timer_pending(&ct->timeout, newtime);
1353 }
1354
1355acct:
1356 if (do_acct)
1357 nf_ct_acct_update(ct, ctinfo, skb->len);
1358}
1359EXPORT_SYMBOL_GPL(__nf_ct_refresh_acct);
1360
1361bool __nf_ct_kill_acct(struct nf_conn *ct,
1362 enum ip_conntrack_info ctinfo,
1363 const struct sk_buff *skb,
1364 int do_acct)
1365{
1366 if (do_acct)
1367 nf_ct_acct_update(ct, ctinfo, skb->len);
1368
1369 if (del_timer(&ct->timeout)) {
1370 ct->timeout.function((unsigned long)ct);
1371 return true;
1372 }
1373 return false;
1374}
1375EXPORT_SYMBOL_GPL(__nf_ct_kill_acct);
1376
1377#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
1378
1379#include <linux/netfilter/nfnetlink.h>
1380#include <linux/netfilter/nfnetlink_conntrack.h>
1381#include <linux/mutex.h>
1382
1383
1384
1385
1386int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb,
1387 const struct nf_conntrack_tuple *tuple)
1388{
1389 if (nla_put_be16(skb, CTA_PROTO_SRC_PORT, tuple->src.u.tcp.port) ||
1390 nla_put_be16(skb, CTA_PROTO_DST_PORT, tuple->dst.u.tcp.port))
1391 goto nla_put_failure;
1392 return 0;
1393
1394nla_put_failure:
1395 return -1;
1396}
1397EXPORT_SYMBOL_GPL(nf_ct_port_tuple_to_nlattr);
1398
1399const struct nla_policy nf_ct_port_nla_policy[CTA_PROTO_MAX+1] = {
1400 [CTA_PROTO_SRC_PORT] = { .type = NLA_U16 },
1401 [CTA_PROTO_DST_PORT] = { .type = NLA_U16 },
1402};
1403EXPORT_SYMBOL_GPL(nf_ct_port_nla_policy);
1404
1405int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[],
1406 struct nf_conntrack_tuple *t)
1407{
1408 if (!tb[CTA_PROTO_SRC_PORT] || !tb[CTA_PROTO_DST_PORT])
1409 return -EINVAL;
1410
1411 t->src.u.tcp.port = nla_get_be16(tb[CTA_PROTO_SRC_PORT]);
1412 t->dst.u.tcp.port = nla_get_be16(tb[CTA_PROTO_DST_PORT]);
1413
1414 return 0;
1415}
1416EXPORT_SYMBOL_GPL(nf_ct_port_nlattr_to_tuple);
1417
1418int nf_ct_port_nlattr_tuple_size(void)
1419{
1420 return nla_policy_len(nf_ct_port_nla_policy, CTA_PROTO_MAX + 1);
1421}
1422EXPORT_SYMBOL_GPL(nf_ct_port_nlattr_tuple_size);
1423#endif
1424
1425
1426static void nf_conntrack_attach(struct sk_buff *nskb, const struct sk_buff *skb)
1427{
1428 struct nf_conn *ct;
1429 enum ip_conntrack_info ctinfo;
1430
1431
1432 ct = nf_ct_get(skb, &ctinfo);
1433 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL)
1434 ctinfo = IP_CT_RELATED_REPLY;
1435 else
1436 ctinfo = IP_CT_RELATED;
1437
1438
1439 nskb->nfct = &ct->ct_general;
1440 nskb->nfctinfo = ctinfo;
1441 nf_conntrack_get(nskb->nfct);
1442}
1443
1444
1445static struct nf_conn *
1446get_next_corpse(struct net *net, int (*iter)(struct nf_conn *i, void *data),
1447 void *data, unsigned int *bucket)
1448{
1449 struct nf_conntrack_tuple_hash *h;
1450 struct nf_conn *ct;
1451 struct hlist_nulls_node *n;
1452 int cpu;
1453 spinlock_t *lockp;
1454
1455 for (; *bucket < nf_conntrack_htable_size; (*bucket)++) {
1456 lockp = &nf_conntrack_locks[*bucket % CONNTRACK_LOCKS];
1457 local_bh_disable();
1458 nf_conntrack_lock(lockp);
1459 if (*bucket < nf_conntrack_htable_size) {
1460 hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[*bucket], hnnode) {
1461 if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
1462 continue;
1463 ct = nf_ct_tuplehash_to_ctrack(h);
1464 if (net_eq(nf_ct_net(ct), net) &&
1465 iter(ct, data))
1466 goto found;
1467 }
1468 }
1469 spin_unlock(lockp);
1470 local_bh_enable();
1471 cond_resched();
1472 }
1473
1474 for_each_possible_cpu(cpu) {
1475 struct ct_pcpu *pcpu = per_cpu_ptr(net->ct.pcpu_lists, cpu);
1476
1477 spin_lock_bh(&pcpu->lock);
1478 hlist_nulls_for_each_entry(h, n, &pcpu->unconfirmed, hnnode) {
1479 ct = nf_ct_tuplehash_to_ctrack(h);
1480 if (iter(ct, data))
1481 set_bit(IPS_DYING_BIT, &ct->status);
1482 }
1483 spin_unlock_bh(&pcpu->lock);
1484 cond_resched();
1485 }
1486 return NULL;
1487found:
1488 atomic_inc(&ct->ct_general.use);
1489 spin_unlock(lockp);
1490 local_bh_enable();
1491 return ct;
1492}
1493
1494void nf_ct_iterate_cleanup(struct net *net,
1495 int (*iter)(struct nf_conn *i, void *data),
1496 void *data, u32 portid, int report)
1497{
1498 struct nf_conn *ct;
1499 unsigned int bucket = 0;
1500
1501 might_sleep();
1502
1503 if (atomic_read(&net->ct.count) == 0)
1504 return;
1505
1506 while ((ct = get_next_corpse(net, iter, data, &bucket)) != NULL) {
1507
1508 if (del_timer(&ct->timeout))
1509 nf_ct_delete(ct, portid, report);
1510
1511
1512
1513 nf_ct_put(ct);
1514 cond_resched();
1515 }
1516}
1517EXPORT_SYMBOL_GPL(nf_ct_iterate_cleanup);
1518
1519static int kill_all(struct nf_conn *i, void *data)
1520{
1521 return 1;
1522}
1523
1524void nf_ct_free_hashtable(void *hash, unsigned int size)
1525{
1526 if (is_vmalloc_addr(hash))
1527 vfree(hash);
1528 else
1529 free_pages((unsigned long)hash,
1530 get_order(sizeof(struct hlist_head) * size));
1531}
1532EXPORT_SYMBOL_GPL(nf_ct_free_hashtable);
1533
1534static int untrack_refs(void)
1535{
1536 int cnt = 0, cpu;
1537
1538 for_each_possible_cpu(cpu) {
1539 struct nf_conn *ct = &per_cpu(nf_conntrack_untracked, cpu);
1540
1541 cnt += atomic_read(&ct->ct_general.use) - 1;
1542 }
1543 return cnt;
1544}
1545
1546void nf_conntrack_cleanup_start(void)
1547{
1548 RCU_INIT_POINTER(ip_ct_attach, NULL);
1549}
1550
1551void nf_conntrack_cleanup_end(void)
1552{
1553 RCU_INIT_POINTER(nf_ct_destroy, NULL);
1554 while (untrack_refs() > 0)
1555 schedule();
1556
1557 nf_ct_free_hashtable(nf_conntrack_hash, nf_conntrack_htable_size);
1558
1559 nf_conntrack_proto_fini();
1560 nf_conntrack_seqadj_fini();
1561 nf_conntrack_labels_fini();
1562 nf_conntrack_helper_fini();
1563 nf_conntrack_timeout_fini();
1564 nf_conntrack_ecache_fini();
1565 nf_conntrack_tstamp_fini();
1566 nf_conntrack_acct_fini();
1567 nf_conntrack_expect_fini();
1568
1569 kmem_cache_destroy(nf_conntrack_cachep);
1570}
1571
1572
1573
1574
1575
1576void nf_conntrack_cleanup_net(struct net *net)
1577{
1578 LIST_HEAD(single);
1579
1580 list_add(&net->exit_list, &single);
1581 nf_conntrack_cleanup_net_list(&single);
1582}
1583
1584void nf_conntrack_cleanup_net_list(struct list_head *net_exit_list)
1585{
1586 int busy;
1587 struct net *net;
1588
1589
1590
1591
1592
1593
1594 synchronize_net();
1595i_see_dead_people:
1596 busy = 0;
1597 list_for_each_entry(net, net_exit_list, exit_list) {
1598 nf_ct_iterate_cleanup(net, kill_all, NULL, 0, 0);
1599 if (atomic_read(&net->ct.count) != 0)
1600 busy = 1;
1601 }
1602 if (busy) {
1603 schedule();
1604 goto i_see_dead_people;
1605 }
1606
1607 list_for_each_entry(net, net_exit_list, exit_list) {
1608 nf_conntrack_proto_pernet_fini(net);
1609 nf_conntrack_helper_pernet_fini(net);
1610 nf_conntrack_ecache_pernet_fini(net);
1611 nf_conntrack_tstamp_pernet_fini(net);
1612 nf_conntrack_acct_pernet_fini(net);
1613 nf_conntrack_expect_pernet_fini(net);
1614 free_percpu(net->ct.stat);
1615 free_percpu(net->ct.pcpu_lists);
1616 }
1617}
1618
1619void *nf_ct_alloc_hashtable(unsigned int *sizep, int nulls)
1620{
1621 struct hlist_nulls_head *hash;
1622 unsigned int nr_slots, i;
1623 size_t sz;
1624
1625 if (*sizep > (UINT_MAX / sizeof(struct hlist_nulls_head)))
1626 return NULL;
1627
1628 BUILD_BUG_ON(sizeof(struct hlist_nulls_head) != sizeof(struct hlist_head));
1629 nr_slots = *sizep = roundup(*sizep, PAGE_SIZE / sizeof(struct hlist_nulls_head));
1630
1631 if (nr_slots > (UINT_MAX / sizeof(struct hlist_nulls_head)))
1632 return NULL;
1633
1634 sz = nr_slots * sizeof(struct hlist_nulls_head);
1635 hash = (void *)__get_free_pages(GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO,
1636 get_order(sz));
1637 if (!hash)
1638 hash = vzalloc(sz);
1639
1640 if (hash && nulls)
1641 for (i = 0; i < nr_slots; i++)
1642 INIT_HLIST_NULLS_HEAD(&hash[i], i);
1643
1644 return hash;
1645}
1646EXPORT_SYMBOL_GPL(nf_ct_alloc_hashtable);
1647
1648int nf_conntrack_hash_resize(unsigned int hashsize)
1649{
1650 int i, bucket;
1651 unsigned int old_size;
1652 struct hlist_nulls_head *hash, *old_hash;
1653 struct nf_conntrack_tuple_hash *h;
1654 struct nf_conn *ct;
1655
1656 if (!hashsize)
1657 return -EINVAL;
1658
1659 hash = nf_ct_alloc_hashtable(&hashsize, 1);
1660 if (!hash)
1661 return -ENOMEM;
1662
1663 old_size = nf_conntrack_htable_size;
1664 if (old_size == hashsize) {
1665 nf_ct_free_hashtable(hash, hashsize);
1666 return 0;
1667 }
1668
1669 local_bh_disable();
1670 nf_conntrack_all_lock();
1671 write_seqcount_begin(&nf_conntrack_generation);
1672
1673
1674
1675
1676
1677
1678
1679 for (i = 0; i < nf_conntrack_htable_size; i++) {
1680 while (!hlist_nulls_empty(&nf_conntrack_hash[i])) {
1681 h = hlist_nulls_entry(nf_conntrack_hash[i].first,
1682 struct nf_conntrack_tuple_hash, hnnode);
1683 ct = nf_ct_tuplehash_to_ctrack(h);
1684 hlist_nulls_del_rcu(&h->hnnode);
1685 bucket = __hash_conntrack(nf_ct_net(ct),
1686 &h->tuple, hashsize);
1687 hlist_nulls_add_head_rcu(&h->hnnode, &hash[bucket]);
1688 }
1689 }
1690 old_size = nf_conntrack_htable_size;
1691 old_hash = nf_conntrack_hash;
1692
1693 nf_conntrack_hash = hash;
1694 nf_conntrack_htable_size = hashsize;
1695
1696 write_seqcount_end(&nf_conntrack_generation);
1697 nf_conntrack_all_unlock();
1698 local_bh_enable();
1699
1700 synchronize_net();
1701 nf_ct_free_hashtable(old_hash, old_size);
1702 return 0;
1703}
1704
1705int nf_conntrack_set_hashsize(const char *val, struct kernel_param *kp)
1706{
1707 unsigned int hashsize;
1708 int rc;
1709
1710 if (current->nsproxy->net_ns != &init_net)
1711 return -EOPNOTSUPP;
1712
1713
1714 if (!nf_conntrack_htable_size)
1715 return param_set_uint(val, kp);
1716
1717 rc = kstrtouint(val, 0, &hashsize);
1718 if (rc)
1719 return rc;
1720
1721 return nf_conntrack_hash_resize(hashsize);
1722}
1723EXPORT_SYMBOL_GPL(nf_conntrack_set_hashsize);
1724
1725module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint,
1726 &nf_conntrack_htable_size, 0600);
1727
1728void nf_ct_untracked_status_or(unsigned long bits)
1729{
1730 int cpu;
1731
1732 for_each_possible_cpu(cpu)
1733 per_cpu(nf_conntrack_untracked, cpu).status |= bits;
1734}
1735EXPORT_SYMBOL_GPL(nf_ct_untracked_status_or);
1736
1737int nf_conntrack_init_start(void)
1738{
1739 int max_factor = 8;
1740 int ret = -ENOMEM;
1741 int i, cpu;
1742
1743 seqcount_init(&nf_conntrack_generation);
1744
1745 for (i = 0; i < CONNTRACK_LOCKS; i++)
1746 spin_lock_init(&nf_conntrack_locks[i]);
1747
1748 if (!nf_conntrack_htable_size) {
1749
1750
1751
1752
1753
1754 nf_conntrack_htable_size
1755 = (((totalram_pages << PAGE_SHIFT) / 16384)
1756 / sizeof(struct hlist_head));
1757 if (totalram_pages > (4 * (1024 * 1024 * 1024 / PAGE_SIZE)))
1758 nf_conntrack_htable_size = 65536;
1759 else if (totalram_pages > (1024 * 1024 * 1024 / PAGE_SIZE))
1760 nf_conntrack_htable_size = 16384;
1761 if (nf_conntrack_htable_size < 32)
1762 nf_conntrack_htable_size = 32;
1763
1764
1765
1766
1767
1768 max_factor = 4;
1769 }
1770
1771 nf_conntrack_hash = nf_ct_alloc_hashtable(&nf_conntrack_htable_size, 1);
1772 if (!nf_conntrack_hash)
1773 return -ENOMEM;
1774
1775 nf_conntrack_max = max_factor * nf_conntrack_htable_size;
1776
1777 nf_conntrack_cachep = kmem_cache_create("nf_conntrack",
1778 sizeof(struct nf_conn), 0,
1779 SLAB_DESTROY_BY_RCU | SLAB_HWCACHE_ALIGN, NULL);
1780 if (!nf_conntrack_cachep)
1781 goto err_cachep;
1782
1783 printk(KERN_INFO "nf_conntrack version %s (%u buckets, %d max)\n",
1784 NF_CONNTRACK_VERSION, nf_conntrack_htable_size,
1785 nf_conntrack_max);
1786
1787 ret = nf_conntrack_expect_init();
1788 if (ret < 0)
1789 goto err_expect;
1790
1791 ret = nf_conntrack_acct_init();
1792 if (ret < 0)
1793 goto err_acct;
1794
1795 ret = nf_conntrack_tstamp_init();
1796 if (ret < 0)
1797 goto err_tstamp;
1798
1799 ret = nf_conntrack_ecache_init();
1800 if (ret < 0)
1801 goto err_ecache;
1802
1803 ret = nf_conntrack_timeout_init();
1804 if (ret < 0)
1805 goto err_timeout;
1806
1807 ret = nf_conntrack_helper_init();
1808 if (ret < 0)
1809 goto err_helper;
1810
1811 ret = nf_conntrack_labels_init();
1812 if (ret < 0)
1813 goto err_labels;
1814
1815 ret = nf_conntrack_seqadj_init();
1816 if (ret < 0)
1817 goto err_seqadj;
1818
1819 ret = nf_conntrack_proto_init();
1820 if (ret < 0)
1821 goto err_proto;
1822
1823
1824 for_each_possible_cpu(cpu) {
1825 struct nf_conn *ct = &per_cpu(nf_conntrack_untracked, cpu);
1826 write_pnet(&ct->ct_net, &init_net);
1827 atomic_set(&ct->ct_general.use, 1);
1828 }
1829
1830 nf_ct_untracked_status_or(IPS_CONFIRMED | IPS_UNTRACKED);
1831 return 0;
1832
1833err_proto:
1834 nf_conntrack_seqadj_fini();
1835err_seqadj:
1836 nf_conntrack_labels_fini();
1837err_labels:
1838 nf_conntrack_helper_fini();
1839err_helper:
1840 nf_conntrack_timeout_fini();
1841err_timeout:
1842 nf_conntrack_ecache_fini();
1843err_ecache:
1844 nf_conntrack_tstamp_fini();
1845err_tstamp:
1846 nf_conntrack_acct_fini();
1847err_acct:
1848 nf_conntrack_expect_fini();
1849err_expect:
1850 kmem_cache_destroy(nf_conntrack_cachep);
1851err_cachep:
1852 nf_ct_free_hashtable(nf_conntrack_hash, nf_conntrack_htable_size);
1853 return ret;
1854}
1855
1856void nf_conntrack_init_end(void)
1857{
1858
1859 RCU_INIT_POINTER(ip_ct_attach, nf_conntrack_attach);
1860 RCU_INIT_POINTER(nf_ct_destroy, destroy_conntrack);
1861}
1862
1863
1864
1865
1866#define UNCONFIRMED_NULLS_VAL ((1<<30)+0)
1867#define DYING_NULLS_VAL ((1<<30)+1)
1868#define TEMPLATE_NULLS_VAL ((1<<30)+2)
1869
1870int nf_conntrack_init_net(struct net *net)
1871{
1872 int ret = -ENOMEM;
1873 int cpu;
1874
1875 atomic_set(&net->ct.count, 0);
1876
1877 net->ct.pcpu_lists = alloc_percpu(struct ct_pcpu);
1878 if (!net->ct.pcpu_lists)
1879 goto err_stat;
1880
1881 for_each_possible_cpu(cpu) {
1882 struct ct_pcpu *pcpu = per_cpu_ptr(net->ct.pcpu_lists, cpu);
1883
1884 spin_lock_init(&pcpu->lock);
1885 INIT_HLIST_NULLS_HEAD(&pcpu->unconfirmed, UNCONFIRMED_NULLS_VAL);
1886 INIT_HLIST_NULLS_HEAD(&pcpu->dying, DYING_NULLS_VAL);
1887 }
1888
1889 net->ct.stat = alloc_percpu(struct ip_conntrack_stat);
1890 if (!net->ct.stat)
1891 goto err_pcpu_lists;
1892
1893 ret = nf_conntrack_expect_pernet_init(net);
1894 if (ret < 0)
1895 goto err_expect;
1896 ret = nf_conntrack_acct_pernet_init(net);
1897 if (ret < 0)
1898 goto err_acct;
1899 ret = nf_conntrack_tstamp_pernet_init(net);
1900 if (ret < 0)
1901 goto err_tstamp;
1902 ret = nf_conntrack_ecache_pernet_init(net);
1903 if (ret < 0)
1904 goto err_ecache;
1905 ret = nf_conntrack_helper_pernet_init(net);
1906 if (ret < 0)
1907 goto err_helper;
1908 ret = nf_conntrack_proto_pernet_init(net);
1909 if (ret < 0)
1910 goto err_proto;
1911 return 0;
1912
1913err_proto:
1914 nf_conntrack_helper_pernet_fini(net);
1915err_helper:
1916 nf_conntrack_ecache_pernet_fini(net);
1917err_ecache:
1918 nf_conntrack_tstamp_pernet_fini(net);
1919err_tstamp:
1920 nf_conntrack_acct_pernet_fini(net);
1921err_acct:
1922 nf_conntrack_expect_pernet_fini(net);
1923err_expect:
1924 free_percpu(net->ct.stat);
1925err_pcpu_lists:
1926 free_percpu(net->ct.pcpu_lists);
1927err_stat:
1928 return ret;
1929}
1930