[NETFILTER]: nf_conntrack: move conntrack protocol sysctls to individual modules
[linux-2.6.git] / net / netfilter / nf_conntrack_core.c
1 /* Connection state tracking for netfilter.  This is separated from,
2    but required by, the NAT layer; it can also be used by an iptables
3    extension. */
4
5 /* (C) 1999-2001 Paul `Rusty' Russell
6  * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
7  * (C) 2003,2004 USAGI/WIDE Project <http://www.linux-ipv6.org>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  *
13  * 23 Apr 2001: Harald Welte <laforge@gnumonks.org>
14  *      - new API and handling of conntrack/nat helpers
15  *      - now capable of multiple expectations for one master
16  * 16 Jul 2002: Harald Welte <laforge@gnumonks.org>
17  *      - add usage/reference counts to ip_conntrack_expect
18  *      - export ip_conntrack[_expect]_{find_get,put} functions
19  * 16 Dec 2003: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
20  *      - generalize L3 protocol denendent part.
21  * 23 Mar 2004: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
22  *      - add support various size of conntrack structures.
23  * 26 Jan 2006: Harald Welte <laforge@netfilter.org>
24  *      - restructure nf_conn (introduce nf_conn_help)
25  *      - redesign 'features' how they were originally intended
26  * 26 Feb 2006: Pablo Neira Ayuso <pablo@eurodev.net>
27  *      - add support for L3 protocol module load on demand.
28  *
29  * Derived from net/ipv4/netfilter/ip_conntrack_core.c
30  */
31
32 #include <linux/types.h>
33 #include <linux/netfilter.h>
34 #include <linux/module.h>
35 #include <linux/skbuff.h>
36 #include <linux/proc_fs.h>
37 #include <linux/vmalloc.h>
38 #include <linux/stddef.h>
39 #include <linux/slab.h>
40 #include <linux/random.h>
41 #include <linux/jhash.h>
42 #include <linux/err.h>
43 #include <linux/percpu.h>
44 #include <linux/moduleparam.h>
45 #include <linux/notifier.h>
46 #include <linux/kernel.h>
47 #include <linux/netdevice.h>
48 #include <linux/socket.h>
49
50 #include <net/netfilter/nf_conntrack.h>
51 #include <net/netfilter/nf_conntrack_l3proto.h>
52 #include <net/netfilter/nf_conntrack_l4proto.h>
53 #include <net/netfilter/nf_conntrack_expect.h>
54 #include <net/netfilter/nf_conntrack_helper.h>
55 #include <net/netfilter/nf_conntrack_core.h>
56
57 #define NF_CONNTRACK_VERSION    "0.5.0"
58
59 #if 0
60 #define DEBUGP printk
61 #else
62 #define DEBUGP(format, args...)
63 #endif
64
65 DEFINE_RWLOCK(nf_conntrack_lock);
66
67 /* nf_conntrack_standalone needs this */
68 atomic_t nf_conntrack_count = ATOMIC_INIT(0);
69
70 void (*nf_conntrack_destroyed)(struct nf_conn *conntrack) = NULL;
71 unsigned int nf_conntrack_htable_size __read_mostly;
72 int nf_conntrack_max __read_mostly;
73 struct list_head *nf_conntrack_hash __read_mostly;
74 struct nf_conn nf_conntrack_untracked __read_mostly;
75 unsigned int nf_ct_log_invalid __read_mostly;
76 LIST_HEAD(unconfirmed);
77 static int nf_conntrack_vmalloc __read_mostly;
78
79 static unsigned int nf_conntrack_next_id;
80
81 DEFINE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
82 EXPORT_PER_CPU_SYMBOL(nf_conntrack_stat);
83
84 /*
85  * This scheme offers various size of "struct nf_conn" dependent on
86  * features(helper, nat, ...)
87  */
88
89 #define NF_CT_FEATURES_NAMELEN  256
90 static struct {
91         /* name of slab cache. printed in /proc/slabinfo */
92         char *name;
93
94         /* size of slab cache */
95         size_t size;
96
97         /* slab cache pointer */
98         kmem_cache_t *cachep;
99
100         /* allocated slab cache + modules which uses this slab cache */
101         int use;
102
103 } nf_ct_cache[NF_CT_F_NUM];
104
105 /* protect members of nf_ct_cache except of "use" */
106 DEFINE_RWLOCK(nf_ct_cache_lock);
107
108 /* This avoids calling kmem_cache_create() with same name simultaneously */
109 static DEFINE_MUTEX(nf_ct_cache_mutex);
110
111 static int nf_conntrack_hash_rnd_initted;
112 static unsigned int nf_conntrack_hash_rnd;
113
114 static u_int32_t __hash_conntrack(const struct nf_conntrack_tuple *tuple,
115                                   unsigned int size, unsigned int rnd)
116 {
117         unsigned int a, b;
118         a = jhash((void *)tuple->src.u3.all, sizeof(tuple->src.u3.all),
119                   ((tuple->src.l3num) << 16) | tuple->dst.protonum);
120         b = jhash((void *)tuple->dst.u3.all, sizeof(tuple->dst.u3.all),
121                         (tuple->src.u.all << 16) | tuple->dst.u.all);
122
123         return jhash_2words(a, b, rnd) % size;
124 }
125
126 static inline u_int32_t hash_conntrack(const struct nf_conntrack_tuple *tuple)
127 {
128         return __hash_conntrack(tuple, nf_conntrack_htable_size,
129                                 nf_conntrack_hash_rnd);
130 }
131
132 int nf_conntrack_register_cache(u_int32_t features, const char *name,
133                                 size_t size)
134 {
135         int ret = 0;
136         char *cache_name;
137         kmem_cache_t *cachep;
138
139         DEBUGP("nf_conntrack_register_cache: features=0x%x, name=%s, size=%d\n",
140                features, name, size);
141
142         if (features < NF_CT_F_BASIC || features >= NF_CT_F_NUM) {
143                 DEBUGP("nf_conntrack_register_cache: invalid features.: 0x%x\n",
144                         features);
145                 return -EINVAL;
146         }
147
148         mutex_lock(&nf_ct_cache_mutex);
149
150         write_lock_bh(&nf_ct_cache_lock);
151         /* e.g: multiple helpers are loaded */
152         if (nf_ct_cache[features].use > 0) {
153                 DEBUGP("nf_conntrack_register_cache: already resisterd.\n");
154                 if ((!strncmp(nf_ct_cache[features].name, name,
155                               NF_CT_FEATURES_NAMELEN))
156                     && nf_ct_cache[features].size == size) {
157                         DEBUGP("nf_conntrack_register_cache: reusing.\n");
158                         nf_ct_cache[features].use++;
159                         ret = 0;
160                 } else
161                         ret = -EBUSY;
162
163                 write_unlock_bh(&nf_ct_cache_lock);
164                 mutex_unlock(&nf_ct_cache_mutex);
165                 return ret;
166         }
167         write_unlock_bh(&nf_ct_cache_lock);
168
169         /*
170          * The memory space for name of slab cache must be alive until
171          * cache is destroyed.
172          */
173         cache_name = kmalloc(sizeof(char)*NF_CT_FEATURES_NAMELEN, GFP_ATOMIC);
174         if (cache_name == NULL) {
175                 DEBUGP("nf_conntrack_register_cache: can't alloc cache_name\n");
176                 ret = -ENOMEM;
177                 goto out_up_mutex;
178         }
179
180         if (strlcpy(cache_name, name, NF_CT_FEATURES_NAMELEN)
181                                                 >= NF_CT_FEATURES_NAMELEN) {
182                 printk("nf_conntrack_register_cache: name too long\n");
183                 ret = -EINVAL;
184                 goto out_free_name;
185         }
186
187         cachep = kmem_cache_create(cache_name, size, 0, 0,
188                                    NULL, NULL);
189         if (!cachep) {
190                 printk("nf_conntrack_register_cache: Can't create slab cache "
191                        "for the features = 0x%x\n", features);
192                 ret = -ENOMEM;
193                 goto out_free_name;
194         }
195
196         write_lock_bh(&nf_ct_cache_lock);
197         nf_ct_cache[features].use = 1;
198         nf_ct_cache[features].size = size;
199         nf_ct_cache[features].cachep = cachep;
200         nf_ct_cache[features].name = cache_name;
201         write_unlock_bh(&nf_ct_cache_lock);
202
203         goto out_up_mutex;
204
205 out_free_name:
206         kfree(cache_name);
207 out_up_mutex:
208         mutex_unlock(&nf_ct_cache_mutex);
209         return ret;
210 }
211
212 /* FIXME: In the current, only nf_conntrack_cleanup() can call this function. */
213 void nf_conntrack_unregister_cache(u_int32_t features)
214 {
215         kmem_cache_t *cachep;
216         char *name;
217
218         /*
219          * This assures that kmem_cache_create() isn't called before destroying
220          * slab cache.
221          */
222         DEBUGP("nf_conntrack_unregister_cache: 0x%04x\n", features);
223         mutex_lock(&nf_ct_cache_mutex);
224
225         write_lock_bh(&nf_ct_cache_lock);
226         if (--nf_ct_cache[features].use > 0) {
227                 write_unlock_bh(&nf_ct_cache_lock);
228                 mutex_unlock(&nf_ct_cache_mutex);
229                 return;
230         }
231         cachep = nf_ct_cache[features].cachep;
232         name = nf_ct_cache[features].name;
233         nf_ct_cache[features].cachep = NULL;
234         nf_ct_cache[features].name = NULL;
235         nf_ct_cache[features].size = 0;
236         write_unlock_bh(&nf_ct_cache_lock);
237
238         synchronize_net();
239
240         kmem_cache_destroy(cachep);
241         kfree(name);
242
243         mutex_unlock(&nf_ct_cache_mutex);
244 }
245
246 int
247 nf_ct_get_tuple(const struct sk_buff *skb,
248                 unsigned int nhoff,
249                 unsigned int dataoff,
250                 u_int16_t l3num,
251                 u_int8_t protonum,
252                 struct nf_conntrack_tuple *tuple,
253                 const struct nf_conntrack_l3proto *l3proto,
254                 const struct nf_conntrack_l4proto *l4proto)
255 {
256         NF_CT_TUPLE_U_BLANK(tuple);
257
258         tuple->src.l3num = l3num;
259         if (l3proto->pkt_to_tuple(skb, nhoff, tuple) == 0)
260                 return 0;
261
262         tuple->dst.protonum = protonum;
263         tuple->dst.dir = IP_CT_DIR_ORIGINAL;
264
265         return l4proto->pkt_to_tuple(skb, dataoff, tuple);
266 }
267
268 int
269 nf_ct_invert_tuple(struct nf_conntrack_tuple *inverse,
270                    const struct nf_conntrack_tuple *orig,
271                    const struct nf_conntrack_l3proto *l3proto,
272                    const struct nf_conntrack_l4proto *l4proto)
273 {
274         NF_CT_TUPLE_U_BLANK(inverse);
275
276         inverse->src.l3num = orig->src.l3num;
277         if (l3proto->invert_tuple(inverse, orig) == 0)
278                 return 0;
279
280         inverse->dst.dir = !orig->dst.dir;
281
282         inverse->dst.protonum = orig->dst.protonum;
283         return l4proto->invert_tuple(inverse, orig);
284 }
285
286 static void
287 clean_from_lists(struct nf_conn *ct)
288 {
289         DEBUGP("clean_from_lists(%p)\n", ct);
290         list_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list);
291         list_del(&ct->tuplehash[IP_CT_DIR_REPLY].list);
292
293         /* Destroy all pending expectations */
294         nf_ct_remove_expectations(ct);
295 }
296
297 static void
298 destroy_conntrack(struct nf_conntrack *nfct)
299 {
300         struct nf_conn *ct = (struct nf_conn *)nfct;
301         struct nf_conntrack_l3proto *l3proto;
302         struct nf_conntrack_l4proto *l4proto;
303
304         DEBUGP("destroy_conntrack(%p)\n", ct);
305         NF_CT_ASSERT(atomic_read(&nfct->use) == 0);
306         NF_CT_ASSERT(!timer_pending(&ct->timeout));
307
308         nf_conntrack_event(IPCT_DESTROY, ct);
309         set_bit(IPS_DYING_BIT, &ct->status);
310
311         /* To make sure we don't get any weird locking issues here:
312          * destroy_conntrack() MUST NOT be called with a write lock
313          * to nf_conntrack_lock!!! -HW */
314         l3proto = __nf_ct_l3proto_find(ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.l3num);
315         if (l3proto && l3proto->destroy)
316                 l3proto->destroy(ct);
317
318         l4proto = __nf_ct_l4proto_find(ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.l3num, ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.protonum);
319         if (l4proto && l4proto->destroy)
320                 l4proto->destroy(ct);
321
322         if (nf_conntrack_destroyed)
323                 nf_conntrack_destroyed(ct);
324
325         write_lock_bh(&nf_conntrack_lock);
326         /* Expectations will have been removed in clean_from_lists,
327          * except TFTP can create an expectation on the first packet,
328          * before connection is in the list, so we need to clean here,
329          * too. */
330         nf_ct_remove_expectations(ct);
331
332         /* We overload first tuple to link into unconfirmed list. */
333         if (!nf_ct_is_confirmed(ct)) {
334                 BUG_ON(list_empty(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list));
335                 list_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list);
336         }
337
338         NF_CT_STAT_INC(delete);
339         write_unlock_bh(&nf_conntrack_lock);
340
341         if (ct->master)
342                 nf_ct_put(ct->master);
343
344         DEBUGP("destroy_conntrack: returning ct=%p to slab\n", ct);
345         nf_conntrack_free(ct);
346 }
347
348 static void death_by_timeout(unsigned long ul_conntrack)
349 {
350         struct nf_conn *ct = (void *)ul_conntrack;
351
352         write_lock_bh(&nf_conntrack_lock);
353         /* Inside lock so preempt is disabled on module removal path.
354          * Otherwise we can get spurious warnings. */
355         NF_CT_STAT_INC(delete_list);
356         clean_from_lists(ct);
357         write_unlock_bh(&nf_conntrack_lock);
358         nf_ct_put(ct);
359 }
360
361 struct nf_conntrack_tuple_hash *
362 __nf_conntrack_find(const struct nf_conntrack_tuple *tuple,
363                     const struct nf_conn *ignored_conntrack)
364 {
365         struct nf_conntrack_tuple_hash *h;
366         unsigned int hash = hash_conntrack(tuple);
367
368         list_for_each_entry(h, &nf_conntrack_hash[hash], list) {
369                 if (nf_ct_tuplehash_to_ctrack(h) != ignored_conntrack &&
370                     nf_ct_tuple_equal(tuple, &h->tuple)) {
371                         NF_CT_STAT_INC(found);
372                         return h;
373                 }
374                 NF_CT_STAT_INC(searched);
375         }
376
377         return NULL;
378 }
379
380 /* Find a connection corresponding to a tuple. */
381 struct nf_conntrack_tuple_hash *
382 nf_conntrack_find_get(const struct nf_conntrack_tuple *tuple,
383                       const struct nf_conn *ignored_conntrack)
384 {
385         struct nf_conntrack_tuple_hash *h;
386
387         read_lock_bh(&nf_conntrack_lock);
388         h = __nf_conntrack_find(tuple, ignored_conntrack);
389         if (h)
390                 atomic_inc(&nf_ct_tuplehash_to_ctrack(h)->ct_general.use);
391         read_unlock_bh(&nf_conntrack_lock);
392
393         return h;
394 }
395
396 static void __nf_conntrack_hash_insert(struct nf_conn *ct,
397                                        unsigned int hash,
398                                        unsigned int repl_hash) 
399 {
400         ct->id = ++nf_conntrack_next_id;
401         list_add(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list,
402                  &nf_conntrack_hash[hash]);
403         list_add(&ct->tuplehash[IP_CT_DIR_REPLY].list,
404                  &nf_conntrack_hash[repl_hash]);
405 }
406
407 void nf_conntrack_hash_insert(struct nf_conn *ct)
408 {
409         unsigned int hash, repl_hash;
410
411         hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
412         repl_hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
413
414         write_lock_bh(&nf_conntrack_lock);
415         __nf_conntrack_hash_insert(ct, hash, repl_hash);
416         write_unlock_bh(&nf_conntrack_lock);
417 }
418
419 /* Confirm a connection given skb; places it in hash table */
420 int
421 __nf_conntrack_confirm(struct sk_buff **pskb)
422 {
423         unsigned int hash, repl_hash;
424         struct nf_conntrack_tuple_hash *h;
425         struct nf_conn *ct;
426         struct nf_conn_help *help;
427         enum ip_conntrack_info ctinfo;
428
429         ct = nf_ct_get(*pskb, &ctinfo);
430
431         /* ipt_REJECT uses nf_conntrack_attach to attach related
432            ICMP/TCP RST packets in other direction.  Actual packet
433            which created connection will be IP_CT_NEW or for an
434            expected connection, IP_CT_RELATED. */
435         if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL)
436                 return NF_ACCEPT;
437
438         hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
439         repl_hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
440
441         /* We're not in hash table, and we refuse to set up related
442            connections for unconfirmed conns.  But packet copies and
443            REJECT will give spurious warnings here. */
444         /* NF_CT_ASSERT(atomic_read(&ct->ct_general.use) == 1); */
445
446         /* No external references means noone else could have
447            confirmed us. */
448         NF_CT_ASSERT(!nf_ct_is_confirmed(ct));
449         DEBUGP("Confirming conntrack %p\n", ct);
450
451         write_lock_bh(&nf_conntrack_lock);
452
453         /* See if there's one in the list already, including reverse:
454            NAT could have grabbed it without realizing, since we're
455            not in the hash.  If there is, we lost race. */
456         list_for_each_entry(h, &nf_conntrack_hash[hash], list)
457                 if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
458                                       &h->tuple))
459                         goto out;
460         list_for_each_entry(h, &nf_conntrack_hash[repl_hash], list)
461                 if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_REPLY].tuple,
462                                       &h->tuple))
463                         goto out;
464
465         /* Remove from unconfirmed list */
466         list_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list);
467
468         __nf_conntrack_hash_insert(ct, hash, repl_hash);
469         /* Timer relative to confirmation time, not original
470            setting time, otherwise we'd get timer wrap in
471            weird delay cases. */
472         ct->timeout.expires += jiffies;
473         add_timer(&ct->timeout);
474         atomic_inc(&ct->ct_general.use);
475         set_bit(IPS_CONFIRMED_BIT, &ct->status);
476         NF_CT_STAT_INC(insert);
477         write_unlock_bh(&nf_conntrack_lock);
478         help = nfct_help(ct);
479         if (help && help->helper)
480                 nf_conntrack_event_cache(IPCT_HELPER, *pskb);
481 #ifdef CONFIG_NF_NAT_NEEDED
482         if (test_bit(IPS_SRC_NAT_DONE_BIT, &ct->status) ||
483             test_bit(IPS_DST_NAT_DONE_BIT, &ct->status))
484                 nf_conntrack_event_cache(IPCT_NATINFO, *pskb);
485 #endif
486         nf_conntrack_event_cache(master_ct(ct) ?
487                                  IPCT_RELATED : IPCT_NEW, *pskb);
488         return NF_ACCEPT;
489
490 out:
491         NF_CT_STAT_INC(insert_failed);
492         write_unlock_bh(&nf_conntrack_lock);
493         return NF_DROP;
494 }
495
496 /* Returns true if a connection correspondings to the tuple (required
497    for NAT). */
498 int
499 nf_conntrack_tuple_taken(const struct nf_conntrack_tuple *tuple,
500                          const struct nf_conn *ignored_conntrack)
501 {
502         struct nf_conntrack_tuple_hash *h;
503
504         read_lock_bh(&nf_conntrack_lock);
505         h = __nf_conntrack_find(tuple, ignored_conntrack);
506         read_unlock_bh(&nf_conntrack_lock);
507
508         return h != NULL;
509 }
510
511 /* There's a small race here where we may free a just-assured
512    connection.  Too bad: we're in trouble anyway. */
513 static int early_drop(struct list_head *chain)
514 {
515         /* Traverse backwards: gives us oldest, which is roughly LRU */
516         struct nf_conntrack_tuple_hash *h;
517         struct nf_conn *ct = NULL, *tmp;
518         int dropped = 0;
519
520         read_lock_bh(&nf_conntrack_lock);
521         list_for_each_entry_reverse(h, chain, list) {
522                 tmp = nf_ct_tuplehash_to_ctrack(h);
523                 if (!test_bit(IPS_ASSURED_BIT, &tmp->status)) {
524                         ct = tmp;
525                         atomic_inc(&ct->ct_general.use);
526                         break;
527                 }
528         }
529         read_unlock_bh(&nf_conntrack_lock);
530
531         if (!ct)
532                 return dropped;
533
534         if (del_timer(&ct->timeout)) {
535                 death_by_timeout((unsigned long)ct);
536                 dropped = 1;
537                 NF_CT_STAT_INC(early_drop);
538         }
539         nf_ct_put(ct);
540         return dropped;
541 }
542
543 static struct nf_conn *
544 __nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
545                      const struct nf_conntrack_tuple *repl,
546                      const struct nf_conntrack_l3proto *l3proto)
547 {
548         struct nf_conn *conntrack = NULL;
549         u_int32_t features = 0;
550         struct nf_conntrack_helper *helper;
551
552         if (unlikely(!nf_conntrack_hash_rnd_initted)) {
553                 get_random_bytes(&nf_conntrack_hash_rnd, 4);
554                 nf_conntrack_hash_rnd_initted = 1;
555         }
556
557         /* We don't want any race condition at early drop stage */
558         atomic_inc(&nf_conntrack_count);
559
560         if (nf_conntrack_max
561             && atomic_read(&nf_conntrack_count) > nf_conntrack_max) {
562                 unsigned int hash = hash_conntrack(orig);
563                 /* Try dropping from this hash chain. */
564                 if (!early_drop(&nf_conntrack_hash[hash])) {
565                         atomic_dec(&nf_conntrack_count);
566                         if (net_ratelimit())
567                                 printk(KERN_WARNING
568                                        "nf_conntrack: table full, dropping"
569                                        " packet.\n");
570                         return ERR_PTR(-ENOMEM);
571                 }
572         }
573
574         /*  find features needed by this conntrack. */
575         features = l3proto->get_features(orig);
576
577         /* FIXME: protect helper list per RCU */
578         read_lock_bh(&nf_conntrack_lock);
579         helper = __nf_ct_helper_find(repl);
580         if (helper)
581                 features |= NF_CT_F_HELP;
582         read_unlock_bh(&nf_conntrack_lock);
583
584         DEBUGP("nf_conntrack_alloc: features=0x%x\n", features);
585
586         read_lock_bh(&nf_ct_cache_lock);
587
588         if (unlikely(!nf_ct_cache[features].use)) {
589                 DEBUGP("nf_conntrack_alloc: not supported features = 0x%x\n",
590                         features);
591                 goto out;
592         }
593
594         conntrack = kmem_cache_alloc(nf_ct_cache[features].cachep, GFP_ATOMIC);
595         if (conntrack == NULL) {
596                 DEBUGP("nf_conntrack_alloc: Can't alloc conntrack from cache\n");
597                 goto out;
598         }
599
600         memset(conntrack, 0, nf_ct_cache[features].size);
601         conntrack->features = features;
602         atomic_set(&conntrack->ct_general.use, 1);
603         conntrack->ct_general.destroy = destroy_conntrack;
604         conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig;
605         conntrack->tuplehash[IP_CT_DIR_REPLY].tuple = *repl;
606         /* Don't set timer yet: wait for confirmation */
607         init_timer(&conntrack->timeout);
608         conntrack->timeout.data = (unsigned long)conntrack;
609         conntrack->timeout.function = death_by_timeout;
610         read_unlock_bh(&nf_ct_cache_lock);
611
612         return conntrack;
613 out:
614         read_unlock_bh(&nf_ct_cache_lock);
615         atomic_dec(&nf_conntrack_count);
616         return conntrack;
617 }
618
619 struct nf_conn *nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
620                                    const struct nf_conntrack_tuple *repl)
621 {
622         struct nf_conntrack_l3proto *l3proto;
623
624         l3proto = __nf_ct_l3proto_find(orig->src.l3num);
625         return __nf_conntrack_alloc(orig, repl, l3proto);
626 }
627
628 void nf_conntrack_free(struct nf_conn *conntrack)
629 {
630         u_int32_t features = conntrack->features;
631         NF_CT_ASSERT(features >= NF_CT_F_BASIC && features < NF_CT_F_NUM);
632         DEBUGP("nf_conntrack_free: features = 0x%x, conntrack=%p\n", features,
633                conntrack);
634         kmem_cache_free(nf_ct_cache[features].cachep, conntrack);
635         atomic_dec(&nf_conntrack_count);
636 }
637
638 /* Allocate a new conntrack: we return -ENOMEM if classification
639    failed due to stress.  Otherwise it really is unclassifiable. */
640 static struct nf_conntrack_tuple_hash *
641 init_conntrack(const struct nf_conntrack_tuple *tuple,
642                struct nf_conntrack_l3proto *l3proto,
643                struct nf_conntrack_l4proto *l4proto,
644                struct sk_buff *skb,
645                unsigned int dataoff)
646 {
647         struct nf_conn *conntrack;
648         struct nf_conntrack_tuple repl_tuple;
649         struct nf_conntrack_expect *exp;
650
651         if (!nf_ct_invert_tuple(&repl_tuple, tuple, l3proto, l4proto)) {
652                 DEBUGP("Can't invert tuple.\n");
653                 return NULL;
654         }
655
656         conntrack = __nf_conntrack_alloc(tuple, &repl_tuple, l3proto);
657         if (conntrack == NULL || IS_ERR(conntrack)) {
658                 DEBUGP("Can't allocate conntrack.\n");
659                 return (struct nf_conntrack_tuple_hash *)conntrack;
660         }
661
662         if (!l4proto->new(conntrack, skb, dataoff)) {
663                 nf_conntrack_free(conntrack);
664                 DEBUGP("init conntrack: can't track with proto module\n");
665                 return NULL;
666         }
667
668         write_lock_bh(&nf_conntrack_lock);
669         exp = find_expectation(tuple);
670
671         if (exp) {
672                 DEBUGP("conntrack: expectation arrives ct=%p exp=%p\n",
673                         conntrack, exp);
674                 /* Welcome, Mr. Bond.  We've been expecting you... */
675                 __set_bit(IPS_EXPECTED_BIT, &conntrack->status);
676                 conntrack->master = exp->master;
677 #ifdef CONFIG_NF_CONNTRACK_MARK
678                 conntrack->mark = exp->master->mark;
679 #endif
680 #ifdef CONFIG_NF_CONNTRACK_SECMARK
681                 conntrack->secmark = exp->master->secmark;
682 #endif
683                 nf_conntrack_get(&conntrack->master->ct_general);
684                 NF_CT_STAT_INC(expect_new);
685         } else {
686                 struct nf_conn_help *help = nfct_help(conntrack);
687
688                 if (help)
689                         help->helper = __nf_ct_helper_find(&repl_tuple);
690                 NF_CT_STAT_INC(new);
691         }
692
693         /* Overload tuple linked list to put us in unconfirmed list. */
694         list_add(&conntrack->tuplehash[IP_CT_DIR_ORIGINAL].list, &unconfirmed);
695
696         write_unlock_bh(&nf_conntrack_lock);
697
698         if (exp) {
699                 if (exp->expectfn)
700                         exp->expectfn(conntrack, exp);
701                 nf_conntrack_expect_put(exp);
702         }
703
704         return &conntrack->tuplehash[IP_CT_DIR_ORIGINAL];
705 }
706
707 /* On success, returns conntrack ptr, sets skb->nfct and ctinfo */
708 static inline struct nf_conn *
709 resolve_normal_ct(struct sk_buff *skb,
710                   unsigned int dataoff,
711                   u_int16_t l3num,
712                   u_int8_t protonum,
713                   struct nf_conntrack_l3proto *l3proto,
714                   struct nf_conntrack_l4proto *l4proto,
715                   int *set_reply,
716                   enum ip_conntrack_info *ctinfo)
717 {
718         struct nf_conntrack_tuple tuple;
719         struct nf_conntrack_tuple_hash *h;
720         struct nf_conn *ct;
721
722         if (!nf_ct_get_tuple(skb, (unsigned int)(skb->nh.raw - skb->data),
723                              dataoff, l3num, protonum, &tuple, l3proto,
724                              l4proto)) {
725                 DEBUGP("resolve_normal_ct: Can't get tuple\n");
726                 return NULL;
727         }
728
729         /* look for tuple match */
730         h = nf_conntrack_find_get(&tuple, NULL);
731         if (!h) {
732                 h = init_conntrack(&tuple, l3proto, l4proto, skb, dataoff);
733                 if (!h)
734                         return NULL;
735                 if (IS_ERR(h))
736                         return (void *)h;
737         }
738         ct = nf_ct_tuplehash_to_ctrack(h);
739
740         /* It exists; we have (non-exclusive) reference. */
741         if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) {
742                 *ctinfo = IP_CT_ESTABLISHED + IP_CT_IS_REPLY;
743                 /* Please set reply bit if this packet OK */
744                 *set_reply = 1;
745         } else {
746                 /* Once we've had two way comms, always ESTABLISHED. */
747                 if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) {
748                         DEBUGP("nf_conntrack_in: normal packet for %p\n", ct);
749                         *ctinfo = IP_CT_ESTABLISHED;
750                 } else if (test_bit(IPS_EXPECTED_BIT, &ct->status)) {
751                         DEBUGP("nf_conntrack_in: related packet for %p\n", ct);
752                         *ctinfo = IP_CT_RELATED;
753                 } else {
754                         DEBUGP("nf_conntrack_in: new packet for %p\n", ct);
755                         *ctinfo = IP_CT_NEW;
756                 }
757                 *set_reply = 0;
758         }
759         skb->nfct = &ct->ct_general;
760         skb->nfctinfo = *ctinfo;
761         return ct;
762 }
763
764 unsigned int
765 nf_conntrack_in(int pf, unsigned int hooknum, struct sk_buff **pskb)
766 {
767         struct nf_conn *ct;
768         enum ip_conntrack_info ctinfo;
769         struct nf_conntrack_l3proto *l3proto;
770         struct nf_conntrack_l4proto *l4proto;
771         unsigned int dataoff;
772         u_int8_t protonum;
773         int set_reply = 0;
774         int ret;
775
776         /* Previously seen (loopback or untracked)?  Ignore. */
777         if ((*pskb)->nfct) {
778                 NF_CT_STAT_INC(ignore);
779                 return NF_ACCEPT;
780         }
781
782         l3proto = __nf_ct_l3proto_find((u_int16_t)pf);
783         if ((ret = l3proto->prepare(pskb, hooknum, &dataoff, &protonum)) <= 0) {
784                 DEBUGP("not prepared to track yet or error occured\n");
785                 return -ret;
786         }
787
788         l4proto = __nf_ct_l4proto_find((u_int16_t)pf, protonum);
789
790         /* It may be an special packet, error, unclean...
791          * inverse of the return code tells to the netfilter
792          * core what to do with the packet. */
793         if (l4proto->error != NULL &&
794             (ret = l4proto->error(*pskb, dataoff, &ctinfo, pf, hooknum)) <= 0) {
795                 NF_CT_STAT_INC(error);
796                 NF_CT_STAT_INC(invalid);
797                 return -ret;
798         }
799
800         ct = resolve_normal_ct(*pskb, dataoff, pf, protonum, l3proto, l4proto,
801                                &set_reply, &ctinfo);
802         if (!ct) {
803                 /* Not valid part of a connection */
804                 NF_CT_STAT_INC(invalid);
805                 return NF_ACCEPT;
806         }
807
808         if (IS_ERR(ct)) {
809                 /* Too stressed to deal. */
810                 NF_CT_STAT_INC(drop);
811                 return NF_DROP;
812         }
813
814         NF_CT_ASSERT((*pskb)->nfct);
815
816         ret = l4proto->packet(ct, *pskb, dataoff, ctinfo, pf, hooknum);
817         if (ret < 0) {
818                 /* Invalid: inverse of the return code tells
819                  * the netfilter core what to do */
820                 DEBUGP("nf_conntrack_in: Can't track with proto module\n");
821                 nf_conntrack_put((*pskb)->nfct);
822                 (*pskb)->nfct = NULL;
823                 NF_CT_STAT_INC(invalid);
824                 return -ret;
825         }
826
827         if (set_reply && !test_and_set_bit(IPS_SEEN_REPLY_BIT, &ct->status))
828                 nf_conntrack_event_cache(IPCT_STATUS, *pskb);
829
830         return ret;
831 }
832
833 int nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse,
834                          const struct nf_conntrack_tuple *orig)
835 {
836         return nf_ct_invert_tuple(inverse, orig,
837                                   __nf_ct_l3proto_find(orig->src.l3num),
838                                   __nf_ct_l4proto_find(orig->src.l3num,
839                                                      orig->dst.protonum));
840 }
841
842 /* Refresh conntrack for this many jiffies and do accounting if do_acct is 1 */
843 void __nf_ct_refresh_acct(struct nf_conn *ct,
844                           enum ip_conntrack_info ctinfo,
845                           const struct sk_buff *skb,
846                           unsigned long extra_jiffies,
847                           int do_acct)
848 {
849         int event = 0;
850
851         NF_CT_ASSERT(ct->timeout.data == (unsigned long)ct);
852         NF_CT_ASSERT(skb);
853
854         write_lock_bh(&nf_conntrack_lock);
855
856         /* Only update if this is not a fixed timeout */
857         if (test_bit(IPS_FIXED_TIMEOUT_BIT, &ct->status)) {
858                 write_unlock_bh(&nf_conntrack_lock);
859                 return;
860         }
861
862         /* If not in hash table, timer will not be active yet */
863         if (!nf_ct_is_confirmed(ct)) {
864                 ct->timeout.expires = extra_jiffies;
865                 event = IPCT_REFRESH;
866         } else {
867                 unsigned long newtime = jiffies + extra_jiffies;
868
869                 /* Only update the timeout if the new timeout is at least
870                    HZ jiffies from the old timeout. Need del_timer for race
871                    avoidance (may already be dying). */
872                 if (newtime - ct->timeout.expires >= HZ
873                     && del_timer(&ct->timeout)) {
874                         ct->timeout.expires = newtime;
875                         add_timer(&ct->timeout);
876                         event = IPCT_REFRESH;
877                 }
878         }
879
880 #ifdef CONFIG_NF_CT_ACCT
881         if (do_acct) {
882                 ct->counters[CTINFO2DIR(ctinfo)].packets++;
883                 ct->counters[CTINFO2DIR(ctinfo)].bytes +=
884                         skb->len - (unsigned int)(skb->nh.raw - skb->data);
885
886                 if ((ct->counters[CTINFO2DIR(ctinfo)].packets & 0x80000000)
887                     || (ct->counters[CTINFO2DIR(ctinfo)].bytes & 0x80000000))
888                         event |= IPCT_COUNTER_FILLING;
889         }
890 #endif
891
892         write_unlock_bh(&nf_conntrack_lock);
893
894         /* must be unlocked when calling event cache */
895         if (event)
896                 nf_conntrack_event_cache(event, skb);
897 }
898
899 #if defined(CONFIG_NF_CT_NETLINK) || \
900     defined(CONFIG_NF_CT_NETLINK_MODULE)
901
902 #include <linux/netfilter/nfnetlink.h>
903 #include <linux/netfilter/nfnetlink_conntrack.h>
904 #include <linux/mutex.h>
905
906
907 /* Generic function for tcp/udp/sctp/dccp and alike. This needs to be
908  * in ip_conntrack_core, since we don't want the protocols to autoload
909  * or depend on ctnetlink */
910 int nf_ct_port_tuple_to_nfattr(struct sk_buff *skb,
911                                const struct nf_conntrack_tuple *tuple)
912 {
913         NFA_PUT(skb, CTA_PROTO_SRC_PORT, sizeof(u_int16_t),
914                 &tuple->src.u.tcp.port);
915         NFA_PUT(skb, CTA_PROTO_DST_PORT, sizeof(u_int16_t),
916                 &tuple->dst.u.tcp.port);
917         return 0;
918
919 nfattr_failure:
920         return -1;
921 }
922
923 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
924         [CTA_PROTO_SRC_PORT-1]  = sizeof(u_int16_t),
925         [CTA_PROTO_DST_PORT-1]  = sizeof(u_int16_t)
926 };
927
928 int nf_ct_port_nfattr_to_tuple(struct nfattr *tb[],
929                                struct nf_conntrack_tuple *t)
930 {
931         if (!tb[CTA_PROTO_SRC_PORT-1] || !tb[CTA_PROTO_DST_PORT-1])
932                 return -EINVAL;
933
934         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
935                 return -EINVAL;
936
937         t->src.u.tcp.port =
938                 *(u_int16_t *)NFA_DATA(tb[CTA_PROTO_SRC_PORT-1]);
939         t->dst.u.tcp.port =
940                 *(u_int16_t *)NFA_DATA(tb[CTA_PROTO_DST_PORT-1]);
941
942         return 0;
943 }
944 #endif
945
946 /* Used by ipt_REJECT and ip6t_REJECT. */
947 void __nf_conntrack_attach(struct sk_buff *nskb, struct sk_buff *skb)
948 {
949         struct nf_conn *ct;
950         enum ip_conntrack_info ctinfo;
951
952         /* This ICMP is in reverse direction to the packet which caused it */
953         ct = nf_ct_get(skb, &ctinfo);
954         if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL)
955                 ctinfo = IP_CT_RELATED + IP_CT_IS_REPLY;
956         else
957                 ctinfo = IP_CT_RELATED;
958
959         /* Attach to new skbuff, and increment count */
960         nskb->nfct = &ct->ct_general;
961         nskb->nfctinfo = ctinfo;
962         nf_conntrack_get(nskb->nfct);
963 }
964
965 static inline int
966 do_iter(const struct nf_conntrack_tuple_hash *i,
967         int (*iter)(struct nf_conn *i, void *data),
968         void *data)
969 {
970         return iter(nf_ct_tuplehash_to_ctrack(i), data);
971 }
972
973 /* Bring out ya dead! */
974 static struct nf_conn *
975 get_next_corpse(int (*iter)(struct nf_conn *i, void *data),
976                 void *data, unsigned int *bucket)
977 {
978         struct nf_conntrack_tuple_hash *h;
979         struct nf_conn *ct;
980
981         write_lock_bh(&nf_conntrack_lock);
982         for (; *bucket < nf_conntrack_htable_size; (*bucket)++) {
983                 list_for_each_entry(h, &nf_conntrack_hash[*bucket], list) {
984                         ct = nf_ct_tuplehash_to_ctrack(h);
985                         if (iter(ct, data))
986                                 goto found;
987                 }
988         }
989         list_for_each_entry(h, &unconfirmed, list) {
990                 ct = nf_ct_tuplehash_to_ctrack(h);
991                 if (iter(ct, data))
992                         goto found;
993         }
994         write_unlock_bh(&nf_conntrack_lock);
995         return NULL;
996 found:
997         atomic_inc(&ct->ct_general.use);
998         write_unlock_bh(&nf_conntrack_lock);
999         return ct;
1000 }
1001
1002 void
1003 nf_ct_iterate_cleanup(int (*iter)(struct nf_conn *i, void *data), void *data)
1004 {
1005         struct nf_conn *ct;
1006         unsigned int bucket = 0;
1007
1008         while ((ct = get_next_corpse(iter, data, &bucket)) != NULL) {
1009                 /* Time to push up daises... */
1010                 if (del_timer(&ct->timeout))
1011                         death_by_timeout((unsigned long)ct);
1012                 /* ... else the timer will get him soon. */
1013
1014                 nf_ct_put(ct);
1015         }
1016 }
1017
1018 static int kill_all(struct nf_conn *i, void *data)
1019 {
1020         return 1;
1021 }
1022
1023 static void free_conntrack_hash(struct list_head *hash, int vmalloced, int size)
1024 {
1025         if (vmalloced)
1026                 vfree(hash);
1027         else
1028                 free_pages((unsigned long)hash, 
1029                            get_order(sizeof(struct list_head) * size));
1030 }
1031
1032 void nf_conntrack_flush()
1033 {
1034         nf_ct_iterate_cleanup(kill_all, NULL);
1035 }
1036
1037 /* Mishearing the voices in his head, our hero wonders how he's
1038    supposed to kill the mall. */
1039 void nf_conntrack_cleanup(void)
1040 {
1041         int i;
1042
1043         ip_ct_attach = NULL;
1044
1045         /* This makes sure all current packets have passed through
1046            netfilter framework.  Roll on, two-stage module
1047            delete... */
1048         synchronize_net();
1049
1050         nf_ct_event_cache_flush();
1051  i_see_dead_people:
1052         nf_conntrack_flush();
1053         if (atomic_read(&nf_conntrack_count) != 0) {
1054                 schedule();
1055                 goto i_see_dead_people;
1056         }
1057         /* wait until all references to nf_conntrack_untracked are dropped */
1058         while (atomic_read(&nf_conntrack_untracked.ct_general.use) > 1)
1059                 schedule();
1060
1061         for (i = 0; i < NF_CT_F_NUM; i++) {
1062                 if (nf_ct_cache[i].use == 0)
1063                         continue;
1064
1065                 NF_CT_ASSERT(nf_ct_cache[i].use == 1);
1066                 nf_ct_cache[i].use = 1;
1067                 nf_conntrack_unregister_cache(i);
1068         }
1069         kmem_cache_destroy(nf_conntrack_expect_cachep);
1070         free_conntrack_hash(nf_conntrack_hash, nf_conntrack_vmalloc,
1071                             nf_conntrack_htable_size);
1072
1073         nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_generic);
1074
1075         /* free l3proto protocol tables */
1076         for (i = 0; i < PF_MAX; i++)
1077                 if (nf_ct_protos[i]) {
1078                         kfree(nf_ct_protos[i]);
1079                         nf_ct_protos[i] = NULL;
1080                 }
1081 }
1082
1083 static struct list_head *alloc_hashtable(int size, int *vmalloced)
1084 {
1085         struct list_head *hash;
1086         unsigned int i;
1087
1088         *vmalloced = 0; 
1089         hash = (void*)__get_free_pages(GFP_KERNEL, 
1090                                        get_order(sizeof(struct list_head)
1091                                                  * size));
1092         if (!hash) { 
1093                 *vmalloced = 1;
1094                 printk(KERN_WARNING "nf_conntrack: falling back to vmalloc.\n");
1095                 hash = vmalloc(sizeof(struct list_head) * size);
1096         }
1097
1098         if (hash)
1099                 for (i = 0; i < size; i++) 
1100                         INIT_LIST_HEAD(&hash[i]);
1101
1102         return hash;
1103 }
1104
1105 int set_hashsize(const char *val, struct kernel_param *kp)
1106 {
1107         int i, bucket, hashsize, vmalloced;
1108         int old_vmalloced, old_size;
1109         int rnd;
1110         struct list_head *hash, *old_hash;
1111         struct nf_conntrack_tuple_hash *h;
1112
1113         /* On boot, we can set this without any fancy locking. */
1114         if (!nf_conntrack_htable_size)
1115                 return param_set_uint(val, kp);
1116
1117         hashsize = simple_strtol(val, NULL, 0);
1118         if (!hashsize)
1119                 return -EINVAL;
1120
1121         hash = alloc_hashtable(hashsize, &vmalloced);
1122         if (!hash)
1123                 return -ENOMEM;
1124
1125         /* We have to rehahs for the new table anyway, so we also can
1126          * use a newrandom seed */
1127         get_random_bytes(&rnd, 4);
1128
1129         write_lock_bh(&nf_conntrack_lock);
1130         for (i = 0; i < nf_conntrack_htable_size; i++) {
1131                 while (!list_empty(&nf_conntrack_hash[i])) {
1132                         h = list_entry(nf_conntrack_hash[i].next,
1133                                        struct nf_conntrack_tuple_hash, list);
1134                         list_del(&h->list);
1135                         bucket = __hash_conntrack(&h->tuple, hashsize, rnd);
1136                         list_add_tail(&h->list, &hash[bucket]);
1137                 }
1138         }
1139         old_size = nf_conntrack_htable_size;
1140         old_vmalloced = nf_conntrack_vmalloc;
1141         old_hash = nf_conntrack_hash;
1142
1143         nf_conntrack_htable_size = hashsize;
1144         nf_conntrack_vmalloc = vmalloced;
1145         nf_conntrack_hash = hash;
1146         nf_conntrack_hash_rnd = rnd;
1147         write_unlock_bh(&nf_conntrack_lock);
1148
1149         free_conntrack_hash(old_hash, old_vmalloced, old_size);
1150         return 0;
1151 }
1152
1153 module_param_call(hashsize, set_hashsize, param_get_uint,
1154                   &nf_conntrack_htable_size, 0600);
1155
1156 int __init nf_conntrack_init(void)
1157 {
1158         unsigned int i;
1159         int ret;
1160
1161         /* Idea from tcp.c: use 1/16384 of memory.  On i386: 32MB
1162          * machine has 256 buckets.  >= 1GB machines have 8192 buckets. */
1163         if (!nf_conntrack_htable_size) {
1164                 nf_conntrack_htable_size
1165                         = (((num_physpages << PAGE_SHIFT) / 16384)
1166                            / sizeof(struct list_head));
1167                 if (num_physpages > (1024 * 1024 * 1024 / PAGE_SIZE))
1168                         nf_conntrack_htable_size = 8192;
1169                 if (nf_conntrack_htable_size < 16)
1170                         nf_conntrack_htable_size = 16;
1171         }
1172         nf_conntrack_max = 8 * nf_conntrack_htable_size;
1173
1174         printk("nf_conntrack version %s (%u buckets, %d max)\n",
1175                NF_CONNTRACK_VERSION, nf_conntrack_htable_size,
1176                nf_conntrack_max);
1177
1178         nf_conntrack_hash = alloc_hashtable(nf_conntrack_htable_size,
1179                                             &nf_conntrack_vmalloc);
1180         if (!nf_conntrack_hash) {
1181                 printk(KERN_ERR "Unable to create nf_conntrack_hash\n");
1182                 goto err_out;
1183         }
1184
1185         ret = nf_conntrack_register_cache(NF_CT_F_BASIC, "nf_conntrack:basic",
1186                                           sizeof(struct nf_conn));
1187         if (ret < 0) {
1188                 printk(KERN_ERR "Unable to create nf_conn slab cache\n");
1189                 goto err_free_hash;
1190         }
1191
1192         nf_conntrack_expect_cachep = kmem_cache_create("nf_conntrack_expect",
1193                                         sizeof(struct nf_conntrack_expect),
1194                                         0, 0, NULL, NULL);
1195         if (!nf_conntrack_expect_cachep) {
1196                 printk(KERN_ERR "Unable to create nf_expect slab cache\n");
1197                 goto err_free_conntrack_slab;
1198         }
1199
1200         ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_generic);
1201         if (ret < 0)
1202                 goto out_free_expect_slab;
1203
1204         /* Don't NEED lock here, but good form anyway. */
1205         write_lock_bh(&nf_conntrack_lock);
1206         for (i = 0; i < AF_MAX; i++)
1207                 nf_ct_l3protos[i] = &nf_conntrack_l3proto_generic;
1208         write_unlock_bh(&nf_conntrack_lock);
1209
1210         /* For use by REJECT target */
1211         ip_ct_attach = __nf_conntrack_attach;
1212
1213         /* Set up fake conntrack:
1214             - to never be deleted, not in any hashes */
1215         atomic_set(&nf_conntrack_untracked.ct_general.use, 1);
1216         /*  - and look it like as a confirmed connection */
1217         set_bit(IPS_CONFIRMED_BIT, &nf_conntrack_untracked.status);
1218
1219         return ret;
1220
1221 out_free_expect_slab:
1222         kmem_cache_destroy(nf_conntrack_expect_cachep);
1223 err_free_conntrack_slab:
1224         nf_conntrack_unregister_cache(NF_CT_F_BASIC);
1225 err_free_hash:
1226         free_conntrack_hash(nf_conntrack_hash, nf_conntrack_vmalloc,
1227                             nf_conntrack_htable_size);
1228 err_out:
1229         return -ENOMEM;
1230 }