Commit | Line | Data |
---|---|---|
1da177e4 LT |
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) 2002-2004 Netfilter Core Team <coreteam@netfilter.org> | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License version 2 as | |
10 | * published by the Free Software Foundation. | |
11 | * | |
12 | * 23 Apr 2001: Harald Welte <laforge@gnumonks.org> | |
13 | * - new API and handling of conntrack/nat helpers | |
14 | * - now capable of multiple expectations for one master | |
15 | * 16 Jul 2002: Harald Welte <laforge@gnumonks.org> | |
16 | * - add usage/reference counts to ip_conntrack_expect | |
17 | * - export ip_conntrack[_expect]_{find_get,put} functions | |
18 | * */ | |
19 | ||
20 | #include <linux/config.h> | |
21 | #include <linux/types.h> | |
22 | #include <linux/icmp.h> | |
23 | #include <linux/ip.h> | |
24 | #include <linux/netfilter.h> | |
25 | #include <linux/netfilter_ipv4.h> | |
26 | #include <linux/module.h> | |
27 | #include <linux/skbuff.h> | |
28 | #include <linux/proc_fs.h> | |
29 | #include <linux/vmalloc.h> | |
30 | #include <net/checksum.h> | |
31 | #include <net/ip.h> | |
32 | #include <linux/stddef.h> | |
33 | #include <linux/sysctl.h> | |
34 | #include <linux/slab.h> | |
35 | #include <linux/random.h> | |
36 | #include <linux/jhash.h> | |
37 | #include <linux/err.h> | |
38 | #include <linux/percpu.h> | |
39 | #include <linux/moduleparam.h> | |
ac3247ba | 40 | #include <linux/notifier.h> |
1da177e4 | 41 | |
e45b1be8 | 42 | /* ip_conntrack_lock protects the main hash table, protocol/helper/expected |
1da177e4 | 43 | registrations, conntrack timers*/ |
e45b1be8 PM |
44 | #define ASSERT_READ_LOCK(x) |
45 | #define ASSERT_WRITE_LOCK(x) | |
1da177e4 LT |
46 | |
47 | #include <linux/netfilter_ipv4/ip_conntrack.h> | |
48 | #include <linux/netfilter_ipv4/ip_conntrack_protocol.h> | |
49 | #include <linux/netfilter_ipv4/ip_conntrack_helper.h> | |
50 | #include <linux/netfilter_ipv4/ip_conntrack_core.h> | |
51 | #include <linux/netfilter_ipv4/listhelp.h> | |
52 | ||
080774a2 | 53 | #define IP_CONNTRACK_VERSION "2.3" |
1da177e4 LT |
54 | |
55 | #if 0 | |
56 | #define DEBUGP printk | |
57 | #else | |
58 | #define DEBUGP(format, args...) | |
59 | #endif | |
60 | ||
e45b1be8 | 61 | DEFINE_RWLOCK(ip_conntrack_lock); |
1da177e4 LT |
62 | |
63 | /* ip_conntrack_standalone needs this */ | |
64 | atomic_t ip_conntrack_count = ATOMIC_INIT(0); | |
65 | ||
66 | void (*ip_conntrack_destroyed)(struct ip_conntrack *conntrack) = NULL; | |
67 | LIST_HEAD(ip_conntrack_expect_list); | |
68 | struct ip_conntrack_protocol *ip_ct_protos[MAX_IP_CT_PROTO]; | |
69 | static LIST_HEAD(helpers); | |
70 | unsigned int ip_conntrack_htable_size = 0; | |
71 | int ip_conntrack_max; | |
72 | struct list_head *ip_conntrack_hash; | |
73 | static kmem_cache_t *ip_conntrack_cachep; | |
74 | static kmem_cache_t *ip_conntrack_expect_cachep; | |
75 | struct ip_conntrack ip_conntrack_untracked; | |
76 | unsigned int ip_ct_log_invalid; | |
77 | static LIST_HEAD(unconfirmed); | |
78 | static int ip_conntrack_vmalloc; | |
79 | ||
080774a2 HW |
80 | static unsigned int ip_conntrack_next_id = 1; |
81 | static unsigned int ip_conntrack_expect_next_id = 1; | |
ac3247ba HW |
82 | #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS |
83 | struct notifier_block *ip_conntrack_chain; | |
84 | struct notifier_block *ip_conntrack_expect_chain; | |
85 | ||
86 | DEFINE_PER_CPU(struct ip_conntrack_ecache, ip_conntrack_ecache); | |
87 | ||
88 | static inline void __deliver_cached_events(struct ip_conntrack_ecache *ecache) | |
89 | { | |
90 | if (is_confirmed(ecache->ct) && !is_dying(ecache->ct) && ecache->events) | |
91 | notifier_call_chain(&ip_conntrack_chain, ecache->events, | |
92 | ecache->ct); | |
93 | ecache->events = 0; | |
94 | } | |
95 | ||
96 | void __ip_ct_deliver_cached_events(struct ip_conntrack_ecache *ecache) | |
97 | { | |
98 | __deliver_cached_events(ecache); | |
99 | } | |
100 | ||
101 | /* Deliver all cached events for a particular conntrack. This is called | |
102 | * by code prior to async packet handling or freeing the skb */ | |
103 | void | |
104 | ip_conntrack_deliver_cached_events_for(const struct ip_conntrack *ct) | |
105 | { | |
106 | struct ip_conntrack_ecache *ecache = | |
107 | &__get_cpu_var(ip_conntrack_ecache); | |
108 | ||
109 | if (!ct) | |
110 | return; | |
111 | ||
112 | if (ecache->ct == ct) { | |
113 | DEBUGP("ecache: delivering event for %p\n", ct); | |
114 | __deliver_cached_events(ecache); | |
115 | } else { | |
116 | if (net_ratelimit()) | |
117 | printk(KERN_WARNING "ecache: want to deliver for %p, " | |
118 | "but cache has %p\n", ct, ecache->ct); | |
119 | } | |
120 | ||
121 | /* signalize that events have already been delivered */ | |
122 | ecache->ct = NULL; | |
123 | } | |
124 | ||
125 | /* Deliver cached events for old pending events, if current conntrack != old */ | |
126 | void ip_conntrack_event_cache_init(const struct sk_buff *skb) | |
127 | { | |
128 | struct ip_conntrack *ct = (struct ip_conntrack *) skb->nfct; | |
129 | struct ip_conntrack_ecache *ecache = | |
130 | &__get_cpu_var(ip_conntrack_ecache); | |
131 | ||
132 | /* take care of delivering potentially old events */ | |
133 | if (ecache->ct != ct) { | |
134 | enum ip_conntrack_info ctinfo; | |
135 | /* we have to check, since at startup the cache is NULL */ | |
136 | if (likely(ecache->ct)) { | |
137 | DEBUGP("ecache: entered for different conntrack: " | |
138 | "ecache->ct=%p, skb->nfct=%p. delivering " | |
139 | "events\n", ecache->ct, ct); | |
140 | __deliver_cached_events(ecache); | |
141 | ip_conntrack_put(ecache->ct); | |
142 | } else { | |
143 | DEBUGP("ecache: entered for conntrack %p, " | |
144 | "cache was clean before\n", ct); | |
145 | } | |
146 | ||
147 | /* initialize for this conntrack/packet */ | |
148 | ecache->ct = ip_conntrack_get(skb, &ctinfo); | |
149 | /* ecache->events cleared by __deliver_cached_devents() */ | |
150 | } else { | |
151 | DEBUGP("ecache: re-entered for conntrack %p.\n", ct); | |
152 | } | |
153 | } | |
154 | ||
155 | #endif /* CONFIG_IP_NF_CONNTRACK_EVENTS */ | |
156 | ||
1da177e4 LT |
157 | DEFINE_PER_CPU(struct ip_conntrack_stat, ip_conntrack_stat); |
158 | ||
1da177e4 LT |
159 | static int ip_conntrack_hash_rnd_initted; |
160 | static unsigned int ip_conntrack_hash_rnd; | |
161 | ||
162 | static u_int32_t | |
163 | hash_conntrack(const struct ip_conntrack_tuple *tuple) | |
164 | { | |
165 | #if 0 | |
166 | dump_tuple(tuple); | |
167 | #endif | |
168 | return (jhash_3words(tuple->src.ip, | |
169 | (tuple->dst.ip ^ tuple->dst.protonum), | |
170 | (tuple->src.u.all | (tuple->dst.u.all << 16)), | |
171 | ip_conntrack_hash_rnd) % ip_conntrack_htable_size); | |
172 | } | |
173 | ||
174 | int | |
175 | ip_ct_get_tuple(const struct iphdr *iph, | |
176 | const struct sk_buff *skb, | |
177 | unsigned int dataoff, | |
178 | struct ip_conntrack_tuple *tuple, | |
179 | const struct ip_conntrack_protocol *protocol) | |
180 | { | |
181 | /* Never happen */ | |
182 | if (iph->frag_off & htons(IP_OFFSET)) { | |
183 | printk("ip_conntrack_core: Frag of proto %u.\n", | |
184 | iph->protocol); | |
185 | return 0; | |
186 | } | |
187 | ||
188 | tuple->src.ip = iph->saddr; | |
189 | tuple->dst.ip = iph->daddr; | |
190 | tuple->dst.protonum = iph->protocol; | |
191 | tuple->dst.dir = IP_CT_DIR_ORIGINAL; | |
192 | ||
193 | return protocol->pkt_to_tuple(skb, dataoff, tuple); | |
194 | } | |
195 | ||
196 | int | |
197 | ip_ct_invert_tuple(struct ip_conntrack_tuple *inverse, | |
198 | const struct ip_conntrack_tuple *orig, | |
199 | const struct ip_conntrack_protocol *protocol) | |
200 | { | |
201 | inverse->src.ip = orig->dst.ip; | |
202 | inverse->dst.ip = orig->src.ip; | |
203 | inverse->dst.protonum = orig->dst.protonum; | |
204 | inverse->dst.dir = !orig->dst.dir; | |
205 | ||
206 | return protocol->invert_tuple(inverse, orig); | |
207 | } | |
208 | ||
209 | ||
210 | /* ip_conntrack_expect helper functions */ | |
1da177e4 LT |
211 | static void unlink_expect(struct ip_conntrack_expect *exp) |
212 | { | |
e45b1be8 | 213 | ASSERT_WRITE_LOCK(&ip_conntrack_lock); |
4acdbdbe | 214 | IP_NF_ASSERT(!timer_pending(&exp->timeout)); |
1da177e4 | 215 | list_del(&exp->list); |
4acdbdbe | 216 | CONNTRACK_STAT_INC(expect_delete); |
1da177e4 LT |
217 | exp->master->expecting--; |
218 | } | |
219 | ||
080774a2 HW |
220 | void __ip_ct_expect_unlink_destroy(struct ip_conntrack_expect *exp) |
221 | { | |
222 | unlink_expect(exp); | |
223 | ip_conntrack_expect_put(exp); | |
224 | } | |
225 | ||
1da177e4 LT |
226 | static void expectation_timed_out(unsigned long ul_expect) |
227 | { | |
228 | struct ip_conntrack_expect *exp = (void *)ul_expect; | |
229 | ||
e45b1be8 | 230 | write_lock_bh(&ip_conntrack_lock); |
1da177e4 | 231 | unlink_expect(exp); |
e45b1be8 | 232 | write_unlock_bh(&ip_conntrack_lock); |
4acdbdbe | 233 | ip_conntrack_expect_put(exp); |
1da177e4 LT |
234 | } |
235 | ||
080774a2 HW |
236 | struct ip_conntrack_expect * |
237 | __ip_conntrack_expect_find(const struct ip_conntrack_tuple *tuple) | |
238 | { | |
239 | struct ip_conntrack_expect *i; | |
240 | ||
241 | list_for_each_entry(i, &ip_conntrack_expect_list, list) { | |
242 | if (ip_ct_tuple_mask_cmp(tuple, &i->tuple, &i->mask)) { | |
243 | atomic_inc(&i->use); | |
244 | return i; | |
245 | } | |
246 | } | |
247 | return NULL; | |
248 | } | |
249 | ||
250 | /* Just find a expectation corresponding to a tuple. */ | |
251 | struct ip_conntrack_expect * | |
252 | ip_conntrack_expect_find_get(const struct ip_conntrack_tuple *tuple) | |
253 | { | |
254 | struct ip_conntrack_expect *i; | |
255 | ||
256 | read_lock_bh(&ip_conntrack_lock); | |
257 | i = __ip_conntrack_expect_find(tuple); | |
258 | read_unlock_bh(&ip_conntrack_lock); | |
259 | ||
260 | return i; | |
261 | } | |
262 | ||
1da177e4 LT |
263 | /* If an expectation for this connection is found, it gets delete from |
264 | * global list then returned. */ | |
265 | static struct ip_conntrack_expect * | |
266 | find_expectation(const struct ip_conntrack_tuple *tuple) | |
267 | { | |
268 | struct ip_conntrack_expect *i; | |
269 | ||
270 | list_for_each_entry(i, &ip_conntrack_expect_list, list) { | |
271 | /* If master is not in hash table yet (ie. packet hasn't left | |
272 | this machine yet), how can other end know about expected? | |
273 | Hence these are not the droids you are looking for (if | |
274 | master ct never got confirmed, we'd hold a reference to it | |
275 | and weird things would happen to future packets). */ | |
276 | if (ip_ct_tuple_mask_cmp(tuple, &i->tuple, &i->mask) | |
277 | && is_confirmed(i->master) | |
278 | && del_timer(&i->timeout)) { | |
279 | unlink_expect(i); | |
280 | return i; | |
281 | } | |
282 | } | |
283 | return NULL; | |
284 | } | |
285 | ||
286 | /* delete all expectations for this conntrack */ | |
080774a2 | 287 | void ip_ct_remove_expectations(struct ip_conntrack *ct) |
1da177e4 LT |
288 | { |
289 | struct ip_conntrack_expect *i, *tmp; | |
290 | ||
291 | /* Optimization: most connection never expect any others. */ | |
292 | if (ct->expecting == 0) | |
293 | return; | |
294 | ||
295 | list_for_each_entry_safe(i, tmp, &ip_conntrack_expect_list, list) { | |
296 | if (i->master == ct && del_timer(&i->timeout)) { | |
297 | unlink_expect(i); | |
4acdbdbe | 298 | ip_conntrack_expect_put(i); |
1da177e4 LT |
299 | } |
300 | } | |
301 | } | |
302 | ||
303 | static void | |
304 | clean_from_lists(struct ip_conntrack *ct) | |
305 | { | |
306 | unsigned int ho, hr; | |
307 | ||
308 | DEBUGP("clean_from_lists(%p)\n", ct); | |
e45b1be8 | 309 | ASSERT_WRITE_LOCK(&ip_conntrack_lock); |
1da177e4 LT |
310 | |
311 | ho = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); | |
312 | hr = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple); | |
313 | LIST_DELETE(&ip_conntrack_hash[ho], &ct->tuplehash[IP_CT_DIR_ORIGINAL]); | |
314 | LIST_DELETE(&ip_conntrack_hash[hr], &ct->tuplehash[IP_CT_DIR_REPLY]); | |
315 | ||
316 | /* Destroy all pending expectations */ | |
080774a2 | 317 | ip_ct_remove_expectations(ct); |
1da177e4 LT |
318 | } |
319 | ||
320 | static void | |
321 | destroy_conntrack(struct nf_conntrack *nfct) | |
322 | { | |
323 | struct ip_conntrack *ct = (struct ip_conntrack *)nfct; | |
324 | struct ip_conntrack_protocol *proto; | |
325 | ||
326 | DEBUGP("destroy_conntrack(%p)\n", ct); | |
327 | IP_NF_ASSERT(atomic_read(&nfct->use) == 0); | |
328 | IP_NF_ASSERT(!timer_pending(&ct->timeout)); | |
329 | ||
ac3247ba HW |
330 | set_bit(IPS_DYING_BIT, &ct->status); |
331 | ||
1da177e4 LT |
332 | /* To make sure we don't get any weird locking issues here: |
333 | * destroy_conntrack() MUST NOT be called with a write lock | |
334 | * to ip_conntrack_lock!!! -HW */ | |
080774a2 | 335 | proto = __ip_conntrack_proto_find(ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.protonum); |
1da177e4 LT |
336 | if (proto && proto->destroy) |
337 | proto->destroy(ct); | |
338 | ||
339 | if (ip_conntrack_destroyed) | |
340 | ip_conntrack_destroyed(ct); | |
341 | ||
e45b1be8 | 342 | write_lock_bh(&ip_conntrack_lock); |
1da177e4 LT |
343 | /* Expectations will have been removed in clean_from_lists, |
344 | * except TFTP can create an expectation on the first packet, | |
345 | * before connection is in the list, so we need to clean here, | |
346 | * too. */ | |
080774a2 | 347 | ip_ct_remove_expectations(ct); |
1da177e4 LT |
348 | |
349 | /* We overload first tuple to link into unconfirmed list. */ | |
350 | if (!is_confirmed(ct)) { | |
351 | BUG_ON(list_empty(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list)); | |
352 | list_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list); | |
353 | } | |
354 | ||
355 | CONNTRACK_STAT_INC(delete); | |
e45b1be8 | 356 | write_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
357 | |
358 | if (ct->master) | |
359 | ip_conntrack_put(ct->master); | |
360 | ||
361 | DEBUGP("destroy_conntrack: returning ct=%p to slab\n", ct); | |
080774a2 | 362 | ip_conntrack_free(ct); |
1da177e4 LT |
363 | } |
364 | ||
365 | static void death_by_timeout(unsigned long ul_conntrack) | |
366 | { | |
367 | struct ip_conntrack *ct = (void *)ul_conntrack; | |
368 | ||
ac3247ba | 369 | ip_conntrack_event(IPCT_DESTROY, ct); |
e45b1be8 | 370 | write_lock_bh(&ip_conntrack_lock); |
1da177e4 LT |
371 | /* Inside lock so preempt is disabled on module removal path. |
372 | * Otherwise we can get spurious warnings. */ | |
373 | CONNTRACK_STAT_INC(delete_list); | |
374 | clean_from_lists(ct); | |
e45b1be8 | 375 | write_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
376 | ip_conntrack_put(ct); |
377 | } | |
378 | ||
379 | static inline int | |
380 | conntrack_tuple_cmp(const struct ip_conntrack_tuple_hash *i, | |
381 | const struct ip_conntrack_tuple *tuple, | |
382 | const struct ip_conntrack *ignored_conntrack) | |
383 | { | |
e45b1be8 | 384 | ASSERT_READ_LOCK(&ip_conntrack_lock); |
1da177e4 LT |
385 | return tuplehash_to_ctrack(i) != ignored_conntrack |
386 | && ip_ct_tuple_equal(tuple, &i->tuple); | |
387 | } | |
388 | ||
080774a2 | 389 | struct ip_conntrack_tuple_hash * |
1da177e4 LT |
390 | __ip_conntrack_find(const struct ip_conntrack_tuple *tuple, |
391 | const struct ip_conntrack *ignored_conntrack) | |
392 | { | |
393 | struct ip_conntrack_tuple_hash *h; | |
394 | unsigned int hash = hash_conntrack(tuple); | |
395 | ||
e45b1be8 | 396 | ASSERT_READ_LOCK(&ip_conntrack_lock); |
1da177e4 LT |
397 | list_for_each_entry(h, &ip_conntrack_hash[hash], list) { |
398 | if (conntrack_tuple_cmp(h, tuple, ignored_conntrack)) { | |
399 | CONNTRACK_STAT_INC(found); | |
400 | return h; | |
401 | } | |
402 | CONNTRACK_STAT_INC(searched); | |
403 | } | |
404 | ||
405 | return NULL; | |
406 | } | |
407 | ||
408 | /* Find a connection corresponding to a tuple. */ | |
409 | struct ip_conntrack_tuple_hash * | |
410 | ip_conntrack_find_get(const struct ip_conntrack_tuple *tuple, | |
411 | const struct ip_conntrack *ignored_conntrack) | |
412 | { | |
413 | struct ip_conntrack_tuple_hash *h; | |
414 | ||
e45b1be8 | 415 | read_lock_bh(&ip_conntrack_lock); |
1da177e4 LT |
416 | h = __ip_conntrack_find(tuple, ignored_conntrack); |
417 | if (h) | |
418 | atomic_inc(&tuplehash_to_ctrack(h)->ct_general.use); | |
e45b1be8 | 419 | read_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
420 | |
421 | return h; | |
422 | } | |
423 | ||
080774a2 HW |
424 | static void __ip_conntrack_hash_insert(struct ip_conntrack *ct, |
425 | unsigned int hash, | |
426 | unsigned int repl_hash) | |
427 | { | |
428 | ct->id = ++ip_conntrack_next_id; | |
429 | list_prepend(&ip_conntrack_hash[hash], | |
430 | &ct->tuplehash[IP_CT_DIR_ORIGINAL].list); | |
431 | list_prepend(&ip_conntrack_hash[repl_hash], | |
432 | &ct->tuplehash[IP_CT_DIR_REPLY].list); | |
433 | } | |
434 | ||
435 | void ip_conntrack_hash_insert(struct ip_conntrack *ct) | |
436 | { | |
437 | unsigned int hash, repl_hash; | |
438 | ||
439 | hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); | |
440 | repl_hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple); | |
441 | ||
442 | write_lock_bh(&ip_conntrack_lock); | |
443 | __ip_conntrack_hash_insert(ct, hash, repl_hash); | |
444 | write_unlock_bh(&ip_conntrack_lock); | |
445 | } | |
446 | ||
1da177e4 LT |
447 | /* Confirm a connection given skb; places it in hash table */ |
448 | int | |
449 | __ip_conntrack_confirm(struct sk_buff **pskb) | |
450 | { | |
451 | unsigned int hash, repl_hash; | |
452 | struct ip_conntrack *ct; | |
453 | enum ip_conntrack_info ctinfo; | |
454 | ||
455 | ct = ip_conntrack_get(*pskb, &ctinfo); | |
456 | ||
457 | /* ipt_REJECT uses ip_conntrack_attach to attach related | |
458 | ICMP/TCP RST packets in other direction. Actual packet | |
459 | which created connection will be IP_CT_NEW or for an | |
460 | expected connection, IP_CT_RELATED. */ | |
461 | if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) | |
462 | return NF_ACCEPT; | |
463 | ||
464 | hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); | |
465 | repl_hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple); | |
466 | ||
467 | /* We're not in hash table, and we refuse to set up related | |
468 | connections for unconfirmed conns. But packet copies and | |
469 | REJECT will give spurious warnings here. */ | |
470 | /* IP_NF_ASSERT(atomic_read(&ct->ct_general.use) == 1); */ | |
471 | ||
472 | /* No external references means noone else could have | |
473 | confirmed us. */ | |
474 | IP_NF_ASSERT(!is_confirmed(ct)); | |
475 | DEBUGP("Confirming conntrack %p\n", ct); | |
476 | ||
e45b1be8 | 477 | write_lock_bh(&ip_conntrack_lock); |
1da177e4 LT |
478 | |
479 | /* See if there's one in the list already, including reverse: | |
480 | NAT could have grabbed it without realizing, since we're | |
481 | not in the hash. If there is, we lost race. */ | |
482 | if (!LIST_FIND(&ip_conntrack_hash[hash], | |
483 | conntrack_tuple_cmp, | |
484 | struct ip_conntrack_tuple_hash *, | |
485 | &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple, NULL) | |
486 | && !LIST_FIND(&ip_conntrack_hash[repl_hash], | |
487 | conntrack_tuple_cmp, | |
488 | struct ip_conntrack_tuple_hash *, | |
489 | &ct->tuplehash[IP_CT_DIR_REPLY].tuple, NULL)) { | |
490 | /* Remove from unconfirmed list */ | |
491 | list_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list); | |
492 | ||
080774a2 | 493 | __ip_conntrack_hash_insert(ct, hash, repl_hash); |
1da177e4 LT |
494 | /* Timer relative to confirmation time, not original |
495 | setting time, otherwise we'd get timer wrap in | |
496 | weird delay cases. */ | |
497 | ct->timeout.expires += jiffies; | |
498 | add_timer(&ct->timeout); | |
499 | atomic_inc(&ct->ct_general.use); | |
500 | set_bit(IPS_CONFIRMED_BIT, &ct->status); | |
501 | CONNTRACK_STAT_INC(insert); | |
e45b1be8 | 502 | write_unlock_bh(&ip_conntrack_lock); |
ac3247ba HW |
503 | if (ct->helper) |
504 | ip_conntrack_event_cache(IPCT_HELPER, *pskb); | |
505 | #ifdef CONFIG_IP_NF_NAT_NEEDED | |
506 | if (test_bit(IPS_SRC_NAT_DONE_BIT, &ct->status) || | |
507 | test_bit(IPS_DST_NAT_DONE_BIT, &ct->status)) | |
508 | ip_conntrack_event_cache(IPCT_NATINFO, *pskb); | |
509 | #endif | |
510 | ip_conntrack_event_cache(master_ct(ct) ? | |
511 | IPCT_RELATED : IPCT_NEW, *pskb); | |
512 | ||
1da177e4 LT |
513 | return NF_ACCEPT; |
514 | } | |
515 | ||
516 | CONNTRACK_STAT_INC(insert_failed); | |
e45b1be8 | 517 | write_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
518 | |
519 | return NF_DROP; | |
520 | } | |
521 | ||
522 | /* Returns true if a connection correspondings to the tuple (required | |
523 | for NAT). */ | |
524 | int | |
525 | ip_conntrack_tuple_taken(const struct ip_conntrack_tuple *tuple, | |
526 | const struct ip_conntrack *ignored_conntrack) | |
527 | { | |
528 | struct ip_conntrack_tuple_hash *h; | |
529 | ||
e45b1be8 | 530 | read_lock_bh(&ip_conntrack_lock); |
1da177e4 | 531 | h = __ip_conntrack_find(tuple, ignored_conntrack); |
e45b1be8 | 532 | read_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
533 | |
534 | return h != NULL; | |
535 | } | |
536 | ||
537 | /* There's a small race here where we may free a just-assured | |
538 | connection. Too bad: we're in trouble anyway. */ | |
539 | static inline int unreplied(const struct ip_conntrack_tuple_hash *i) | |
540 | { | |
541 | return !(test_bit(IPS_ASSURED_BIT, &tuplehash_to_ctrack(i)->status)); | |
542 | } | |
543 | ||
544 | static int early_drop(struct list_head *chain) | |
545 | { | |
546 | /* Traverse backwards: gives us oldest, which is roughly LRU */ | |
547 | struct ip_conntrack_tuple_hash *h; | |
548 | struct ip_conntrack *ct = NULL; | |
549 | int dropped = 0; | |
550 | ||
e45b1be8 | 551 | read_lock_bh(&ip_conntrack_lock); |
1da177e4 LT |
552 | h = LIST_FIND_B(chain, unreplied, struct ip_conntrack_tuple_hash *); |
553 | if (h) { | |
554 | ct = tuplehash_to_ctrack(h); | |
555 | atomic_inc(&ct->ct_general.use); | |
556 | } | |
e45b1be8 | 557 | read_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
558 | |
559 | if (!ct) | |
560 | return dropped; | |
561 | ||
562 | if (del_timer(&ct->timeout)) { | |
563 | death_by_timeout((unsigned long)ct); | |
564 | dropped = 1; | |
565 | CONNTRACK_STAT_INC(early_drop); | |
566 | } | |
567 | ip_conntrack_put(ct); | |
568 | return dropped; | |
569 | } | |
570 | ||
571 | static inline int helper_cmp(const struct ip_conntrack_helper *i, | |
572 | const struct ip_conntrack_tuple *rtuple) | |
573 | { | |
574 | return ip_ct_tuple_mask_cmp(rtuple, &i->tuple, &i->mask); | |
575 | } | |
576 | ||
080774a2 HW |
577 | static struct ip_conntrack_helper * |
578 | __ip_conntrack_helper_find( const struct ip_conntrack_tuple *tuple) | |
1da177e4 LT |
579 | { |
580 | return LIST_FIND(&helpers, helper_cmp, | |
581 | struct ip_conntrack_helper *, | |
582 | tuple); | |
583 | } | |
584 | ||
080774a2 HW |
585 | struct ip_conntrack_helper * |
586 | ip_conntrack_helper_find_get( const struct ip_conntrack_tuple *tuple) | |
587 | { | |
588 | struct ip_conntrack_helper *helper; | |
589 | ||
590 | /* need ip_conntrack_lock to assure that helper exists until | |
591 | * try_module_get() is called */ | |
592 | read_lock_bh(&ip_conntrack_lock); | |
593 | ||
594 | helper = __ip_conntrack_helper_find(tuple); | |
595 | if (helper) { | |
596 | /* need to increase module usage count to assure helper will | |
597 | * not go away while the caller is e.g. busy putting a | |
598 | * conntrack in the hash that uses the helper */ | |
599 | if (!try_module_get(helper->me)) | |
600 | helper = NULL; | |
601 | } | |
602 | ||
603 | read_unlock_bh(&ip_conntrack_lock); | |
604 | ||
605 | return helper; | |
606 | } | |
607 | ||
608 | void ip_conntrack_helper_put(struct ip_conntrack_helper *helper) | |
609 | { | |
610 | module_put(helper->me); | |
611 | } | |
612 | ||
613 | struct ip_conntrack_protocol * | |
614 | __ip_conntrack_proto_find(u_int8_t protocol) | |
615 | { | |
616 | return ip_ct_protos[protocol]; | |
617 | } | |
618 | ||
619 | /* this is guaranteed to always return a valid protocol helper, since | |
620 | * it falls back to generic_protocol */ | |
621 | struct ip_conntrack_protocol * | |
622 | ip_conntrack_proto_find_get(u_int8_t protocol) | |
623 | { | |
624 | struct ip_conntrack_protocol *p; | |
625 | ||
626 | preempt_disable(); | |
627 | p = __ip_conntrack_proto_find(protocol); | |
628 | if (p) { | |
629 | if (!try_module_get(p->me)) | |
630 | p = &ip_conntrack_generic_protocol; | |
631 | } | |
632 | preempt_enable(); | |
633 | ||
634 | return p; | |
635 | } | |
636 | ||
637 | void ip_conntrack_proto_put(struct ip_conntrack_protocol *p) | |
638 | { | |
639 | module_put(p->me); | |
640 | } | |
641 | ||
642 | struct ip_conntrack *ip_conntrack_alloc(struct ip_conntrack_tuple *orig, | |
643 | struct ip_conntrack_tuple *repl) | |
1da177e4 LT |
644 | { |
645 | struct ip_conntrack *conntrack; | |
1da177e4 LT |
646 | |
647 | if (!ip_conntrack_hash_rnd_initted) { | |
648 | get_random_bytes(&ip_conntrack_hash_rnd, 4); | |
649 | ip_conntrack_hash_rnd_initted = 1; | |
650 | } | |
651 | ||
1da177e4 LT |
652 | if (ip_conntrack_max |
653 | && atomic_read(&ip_conntrack_count) >= ip_conntrack_max) { | |
080774a2 | 654 | unsigned int hash = hash_conntrack(orig); |
1da177e4 LT |
655 | /* Try dropping from this hash chain. */ |
656 | if (!early_drop(&ip_conntrack_hash[hash])) { | |
657 | if (net_ratelimit()) | |
658 | printk(KERN_WARNING | |
659 | "ip_conntrack: table full, dropping" | |
660 | " packet.\n"); | |
661 | return ERR_PTR(-ENOMEM); | |
662 | } | |
663 | } | |
664 | ||
1da177e4 LT |
665 | conntrack = kmem_cache_alloc(ip_conntrack_cachep, GFP_ATOMIC); |
666 | if (!conntrack) { | |
667 | DEBUGP("Can't allocate conntrack.\n"); | |
080774a2 | 668 | return NULL; |
1da177e4 LT |
669 | } |
670 | ||
671 | memset(conntrack, 0, sizeof(*conntrack)); | |
672 | atomic_set(&conntrack->ct_general.use, 1); | |
673 | conntrack->ct_general.destroy = destroy_conntrack; | |
080774a2 HW |
674 | conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig; |
675 | conntrack->tuplehash[IP_CT_DIR_REPLY].tuple = *repl; | |
1da177e4 LT |
676 | /* Don't set timer yet: wait for confirmation */ |
677 | init_timer(&conntrack->timeout); | |
678 | conntrack->timeout.data = (unsigned long)conntrack; | |
679 | conntrack->timeout.function = death_by_timeout; | |
680 | ||
080774a2 HW |
681 | atomic_inc(&ip_conntrack_count); |
682 | ||
683 | return conntrack; | |
684 | } | |
685 | ||
686 | void | |
687 | ip_conntrack_free(struct ip_conntrack *conntrack) | |
688 | { | |
689 | atomic_dec(&ip_conntrack_count); | |
690 | kmem_cache_free(ip_conntrack_cachep, conntrack); | |
691 | } | |
692 | ||
693 | /* Allocate a new conntrack: we return -ENOMEM if classification | |
694 | * failed due to stress. Otherwise it really is unclassifiable */ | |
695 | static struct ip_conntrack_tuple_hash * | |
696 | init_conntrack(struct ip_conntrack_tuple *tuple, | |
697 | struct ip_conntrack_protocol *protocol, | |
698 | struct sk_buff *skb) | |
699 | { | |
700 | struct ip_conntrack *conntrack; | |
701 | struct ip_conntrack_tuple repl_tuple; | |
702 | struct ip_conntrack_expect *exp; | |
703 | ||
704 | if (!ip_ct_invert_tuple(&repl_tuple, tuple, protocol)) { | |
705 | DEBUGP("Can't invert tuple.\n"); | |
706 | return NULL; | |
707 | } | |
708 | ||
709 | if (!(conntrack = ip_conntrack_alloc(tuple, &repl_tuple))) | |
710 | return NULL; | |
711 | ||
712 | if (!protocol->new(conntrack, skb)) { | |
713 | ip_conntrack_free(conntrack); | |
714 | return NULL; | |
715 | } | |
716 | ||
e45b1be8 | 717 | write_lock_bh(&ip_conntrack_lock); |
1da177e4 LT |
718 | exp = find_expectation(tuple); |
719 | ||
720 | if (exp) { | |
721 | DEBUGP("conntrack: expectation arrives ct=%p exp=%p\n", | |
722 | conntrack, exp); | |
723 | /* Welcome, Mr. Bond. We've been expecting you... */ | |
724 | __set_bit(IPS_EXPECTED_BIT, &conntrack->status); | |
725 | conntrack->master = exp->master; | |
7cee432a | 726 | #ifdef CONFIG_IP_NF_CONNTRACK_MARK |
1da177e4 | 727 | conntrack->mark = exp->master->mark; |
1f494c0e HW |
728 | #endif |
729 | #if defined(CONFIG_IP_NF_TARGET_MASQUERADE) || \ | |
730 | defined(CONFIG_IP_NF_TARGET_MASQUERADE_MODULE) | |
731 | /* this is ugly, but there is no other place where to put it */ | |
732 | conntrack->nat.masq_index = exp->master->nat.masq_index; | |
1da177e4 LT |
733 | #endif |
734 | nf_conntrack_get(&conntrack->master->ct_general); | |
735 | CONNTRACK_STAT_INC(expect_new); | |
736 | } else { | |
080774a2 | 737 | conntrack->helper = __ip_conntrack_helper_find(&repl_tuple); |
1da177e4 LT |
738 | |
739 | CONNTRACK_STAT_INC(new); | |
740 | } | |
741 | ||
742 | /* Overload tuple linked list to put us in unconfirmed list. */ | |
743 | list_add(&conntrack->tuplehash[IP_CT_DIR_ORIGINAL].list, &unconfirmed); | |
744 | ||
e45b1be8 | 745 | write_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
746 | |
747 | if (exp) { | |
748 | if (exp->expectfn) | |
749 | exp->expectfn(conntrack, exp); | |
4acdbdbe | 750 | ip_conntrack_expect_put(exp); |
1da177e4 LT |
751 | } |
752 | ||
753 | return &conntrack->tuplehash[IP_CT_DIR_ORIGINAL]; | |
754 | } | |
755 | ||
756 | /* On success, returns conntrack ptr, sets skb->nfct and ctinfo */ | |
757 | static inline struct ip_conntrack * | |
758 | resolve_normal_ct(struct sk_buff *skb, | |
759 | struct ip_conntrack_protocol *proto, | |
760 | int *set_reply, | |
761 | unsigned int hooknum, | |
762 | enum ip_conntrack_info *ctinfo) | |
763 | { | |
764 | struct ip_conntrack_tuple tuple; | |
765 | struct ip_conntrack_tuple_hash *h; | |
766 | struct ip_conntrack *ct; | |
767 | ||
768 | IP_NF_ASSERT((skb->nh.iph->frag_off & htons(IP_OFFSET)) == 0); | |
769 | ||
770 | if (!ip_ct_get_tuple(skb->nh.iph, skb, skb->nh.iph->ihl*4, | |
771 | &tuple,proto)) | |
772 | return NULL; | |
773 | ||
774 | /* look for tuple match */ | |
775 | h = ip_conntrack_find_get(&tuple, NULL); | |
776 | if (!h) { | |
777 | h = init_conntrack(&tuple, proto, skb); | |
778 | if (!h) | |
779 | return NULL; | |
780 | if (IS_ERR(h)) | |
781 | return (void *)h; | |
782 | } | |
783 | ct = tuplehash_to_ctrack(h); | |
784 | ||
785 | /* It exists; we have (non-exclusive) reference. */ | |
786 | if (DIRECTION(h) == IP_CT_DIR_REPLY) { | |
787 | *ctinfo = IP_CT_ESTABLISHED + IP_CT_IS_REPLY; | |
788 | /* Please set reply bit if this packet OK */ | |
789 | *set_reply = 1; | |
790 | } else { | |
791 | /* Once we've had two way comms, always ESTABLISHED. */ | |
792 | if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) { | |
793 | DEBUGP("ip_conntrack_in: normal packet for %p\n", | |
794 | ct); | |
795 | *ctinfo = IP_CT_ESTABLISHED; | |
796 | } else if (test_bit(IPS_EXPECTED_BIT, &ct->status)) { | |
797 | DEBUGP("ip_conntrack_in: related packet for %p\n", | |
798 | ct); | |
799 | *ctinfo = IP_CT_RELATED; | |
800 | } else { | |
801 | DEBUGP("ip_conntrack_in: new packet for %p\n", | |
802 | ct); | |
803 | *ctinfo = IP_CT_NEW; | |
804 | } | |
805 | *set_reply = 0; | |
806 | } | |
807 | skb->nfct = &ct->ct_general; | |
808 | skb->nfctinfo = *ctinfo; | |
809 | return ct; | |
810 | } | |
811 | ||
812 | /* Netfilter hook itself. */ | |
813 | unsigned int ip_conntrack_in(unsigned int hooknum, | |
814 | struct sk_buff **pskb, | |
815 | const struct net_device *in, | |
816 | const struct net_device *out, | |
817 | int (*okfn)(struct sk_buff *)) | |
818 | { | |
819 | struct ip_conntrack *ct; | |
820 | enum ip_conntrack_info ctinfo; | |
821 | struct ip_conntrack_protocol *proto; | |
ac3247ba | 822 | int set_reply = 0; |
1da177e4 LT |
823 | int ret; |
824 | ||
825 | /* Previously seen (loopback or untracked)? Ignore. */ | |
826 | if ((*pskb)->nfct) { | |
827 | CONNTRACK_STAT_INC(ignore); | |
828 | return NF_ACCEPT; | |
829 | } | |
830 | ||
831 | /* Never happen */ | |
832 | if ((*pskb)->nh.iph->frag_off & htons(IP_OFFSET)) { | |
833 | if (net_ratelimit()) { | |
834 | printk(KERN_ERR "ip_conntrack_in: Frag of proto %u (hook=%u)\n", | |
835 | (*pskb)->nh.iph->protocol, hooknum); | |
836 | } | |
837 | return NF_DROP; | |
838 | } | |
839 | ||
1da177e4 LT |
840 | /* Doesn't cover locally-generated broadcast, so not worth it. */ |
841 | #if 0 | |
842 | /* Ignore broadcast: no `connection'. */ | |
843 | if ((*pskb)->pkt_type == PACKET_BROADCAST) { | |
844 | printk("Broadcast packet!\n"); | |
845 | return NF_ACCEPT; | |
846 | } else if (((*pskb)->nh.iph->daddr & htonl(0x000000FF)) | |
847 | == htonl(0x000000FF)) { | |
848 | printk("Should bcast: %u.%u.%u.%u->%u.%u.%u.%u (sk=%p, ptype=%u)\n", | |
849 | NIPQUAD((*pskb)->nh.iph->saddr), | |
850 | NIPQUAD((*pskb)->nh.iph->daddr), | |
851 | (*pskb)->sk, (*pskb)->pkt_type); | |
852 | } | |
853 | #endif | |
854 | ||
080774a2 | 855 | proto = __ip_conntrack_proto_find((*pskb)->nh.iph->protocol); |
1da177e4 LT |
856 | |
857 | /* It may be an special packet, error, unclean... | |
858 | * inverse of the return code tells to the netfilter | |
859 | * core what to do with the packet. */ | |
860 | if (proto->error != NULL | |
861 | && (ret = proto->error(*pskb, &ctinfo, hooknum)) <= 0) { | |
862 | CONNTRACK_STAT_INC(error); | |
863 | CONNTRACK_STAT_INC(invalid); | |
864 | return -ret; | |
865 | } | |
866 | ||
867 | if (!(ct = resolve_normal_ct(*pskb, proto,&set_reply,hooknum,&ctinfo))) { | |
868 | /* Not valid part of a connection */ | |
869 | CONNTRACK_STAT_INC(invalid); | |
870 | return NF_ACCEPT; | |
871 | } | |
872 | ||
873 | if (IS_ERR(ct)) { | |
874 | /* Too stressed to deal. */ | |
875 | CONNTRACK_STAT_INC(drop); | |
876 | return NF_DROP; | |
877 | } | |
878 | ||
879 | IP_NF_ASSERT((*pskb)->nfct); | |
880 | ||
ac3247ba HW |
881 | ip_conntrack_event_cache_init(*pskb); |
882 | ||
1da177e4 LT |
883 | ret = proto->packet(ct, *pskb, ctinfo); |
884 | if (ret < 0) { | |
885 | /* Invalid: inverse of the return code tells | |
886 | * the netfilter core what to do*/ | |
887 | nf_conntrack_put((*pskb)->nfct); | |
888 | (*pskb)->nfct = NULL; | |
889 | CONNTRACK_STAT_INC(invalid); | |
890 | return -ret; | |
891 | } | |
892 | ||
ac3247ba HW |
893 | if (set_reply && !test_and_set_bit(IPS_SEEN_REPLY_BIT, &ct->status)) |
894 | ip_conntrack_event_cache(IPCT_STATUS, *pskb); | |
1da177e4 LT |
895 | |
896 | return ret; | |
897 | } | |
898 | ||
899 | int invert_tuplepr(struct ip_conntrack_tuple *inverse, | |
900 | const struct ip_conntrack_tuple *orig) | |
901 | { | |
902 | return ip_ct_invert_tuple(inverse, orig, | |
080774a2 | 903 | __ip_conntrack_proto_find(orig->dst.protonum)); |
1da177e4 LT |
904 | } |
905 | ||
906 | /* Would two expected things clash? */ | |
907 | static inline int expect_clash(const struct ip_conntrack_expect *a, | |
908 | const struct ip_conntrack_expect *b) | |
909 | { | |
910 | /* Part covered by intersection of masks must be unequal, | |
911 | otherwise they clash */ | |
912 | struct ip_conntrack_tuple intersect_mask | |
913 | = { { a->mask.src.ip & b->mask.src.ip, | |
914 | { a->mask.src.u.all & b->mask.src.u.all } }, | |
915 | { a->mask.dst.ip & b->mask.dst.ip, | |
916 | { a->mask.dst.u.all & b->mask.dst.u.all }, | |
917 | a->mask.dst.protonum & b->mask.dst.protonum } }; | |
918 | ||
919 | return ip_ct_tuple_mask_cmp(&a->tuple, &b->tuple, &intersect_mask); | |
920 | } | |
921 | ||
922 | static inline int expect_matches(const struct ip_conntrack_expect *a, | |
923 | const struct ip_conntrack_expect *b) | |
924 | { | |
925 | return a->master == b->master | |
926 | && ip_ct_tuple_equal(&a->tuple, &b->tuple) | |
927 | && ip_ct_tuple_equal(&a->mask, &b->mask); | |
928 | } | |
929 | ||
930 | /* Generally a bad idea to call this: could have matched already. */ | |
931 | void ip_conntrack_unexpect_related(struct ip_conntrack_expect *exp) | |
932 | { | |
933 | struct ip_conntrack_expect *i; | |
934 | ||
e45b1be8 | 935 | write_lock_bh(&ip_conntrack_lock); |
1da177e4 LT |
936 | /* choose the the oldest expectation to evict */ |
937 | list_for_each_entry_reverse(i, &ip_conntrack_expect_list, list) { | |
938 | if (expect_matches(i, exp) && del_timer(&i->timeout)) { | |
939 | unlink_expect(i); | |
e45b1be8 | 940 | write_unlock_bh(&ip_conntrack_lock); |
4acdbdbe | 941 | ip_conntrack_expect_put(i); |
1da177e4 LT |
942 | return; |
943 | } | |
944 | } | |
e45b1be8 | 945 | write_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
946 | } |
947 | ||
4acdbdbe | 948 | struct ip_conntrack_expect *ip_conntrack_expect_alloc(struct ip_conntrack *me) |
1da177e4 LT |
949 | { |
950 | struct ip_conntrack_expect *new; | |
951 | ||
952 | new = kmem_cache_alloc(ip_conntrack_expect_cachep, GFP_ATOMIC); | |
953 | if (!new) { | |
954 | DEBUGP("expect_related: OOM allocating expect\n"); | |
955 | return NULL; | |
956 | } | |
4acdbdbe RR |
957 | new->master = me; |
958 | atomic_inc(&new->master->ct_general.use); | |
959 | atomic_set(&new->use, 1); | |
1da177e4 LT |
960 | return new; |
961 | } | |
962 | ||
4acdbdbe | 963 | void ip_conntrack_expect_put(struct ip_conntrack_expect *exp) |
1da177e4 | 964 | { |
4acdbdbe RR |
965 | if (atomic_dec_and_test(&exp->use)) { |
966 | ip_conntrack_put(exp->master); | |
967 | kmem_cache_free(ip_conntrack_expect_cachep, exp); | |
968 | } | |
1da177e4 LT |
969 | } |
970 | ||
971 | static void ip_conntrack_expect_insert(struct ip_conntrack_expect *exp) | |
972 | { | |
4acdbdbe | 973 | atomic_inc(&exp->use); |
1da177e4 LT |
974 | exp->master->expecting++; |
975 | list_add(&exp->list, &ip_conntrack_expect_list); | |
976 | ||
1d3cdb41 PO |
977 | init_timer(&exp->timeout); |
978 | exp->timeout.data = (unsigned long)exp; | |
979 | exp->timeout.function = expectation_timed_out; | |
980 | exp->timeout.expires = jiffies + exp->master->helper->timeout * HZ; | |
981 | add_timer(&exp->timeout); | |
1da177e4 | 982 | |
080774a2 HW |
983 | exp->id = ++ip_conntrack_expect_next_id; |
984 | atomic_inc(&exp->use); | |
1da177e4 LT |
985 | CONNTRACK_STAT_INC(expect_create); |
986 | } | |
987 | ||
988 | /* Race with expectations being used means we could have none to find; OK. */ | |
989 | static void evict_oldest_expect(struct ip_conntrack *master) | |
990 | { | |
991 | struct ip_conntrack_expect *i; | |
992 | ||
993 | list_for_each_entry_reverse(i, &ip_conntrack_expect_list, list) { | |
994 | if (i->master == master) { | |
995 | if (del_timer(&i->timeout)) { | |
996 | unlink_expect(i); | |
4acdbdbe | 997 | ip_conntrack_expect_put(i); |
1da177e4 LT |
998 | } |
999 | break; | |
1000 | } | |
1001 | } | |
1002 | } | |
1003 | ||
1004 | static inline int refresh_timer(struct ip_conntrack_expect *i) | |
1005 | { | |
1006 | if (!del_timer(&i->timeout)) | |
1007 | return 0; | |
1008 | ||
1009 | i->timeout.expires = jiffies + i->master->helper->timeout*HZ; | |
1010 | add_timer(&i->timeout); | |
1011 | return 1; | |
1012 | } | |
1013 | ||
1014 | int ip_conntrack_expect_related(struct ip_conntrack_expect *expect) | |
1015 | { | |
1016 | struct ip_conntrack_expect *i; | |
1017 | int ret; | |
1018 | ||
1019 | DEBUGP("ip_conntrack_expect_related %p\n", related_to); | |
1020 | DEBUGP("tuple: "); DUMP_TUPLE(&expect->tuple); | |
1021 | DEBUGP("mask: "); DUMP_TUPLE(&expect->mask); | |
1022 | ||
e45b1be8 | 1023 | write_lock_bh(&ip_conntrack_lock); |
1da177e4 LT |
1024 | list_for_each_entry(i, &ip_conntrack_expect_list, list) { |
1025 | if (expect_matches(i, expect)) { | |
1026 | /* Refresh timer: if it's dying, ignore.. */ | |
1027 | if (refresh_timer(i)) { | |
1028 | ret = 0; | |
1da177e4 LT |
1029 | goto out; |
1030 | } | |
1031 | } else if (expect_clash(i, expect)) { | |
1032 | ret = -EBUSY; | |
1033 | goto out; | |
1034 | } | |
1035 | } | |
1036 | ||
1037 | /* Will be over limit? */ | |
1038 | if (expect->master->helper->max_expected && | |
1039 | expect->master->expecting >= expect->master->helper->max_expected) | |
1040 | evict_oldest_expect(expect->master); | |
1041 | ||
1042 | ip_conntrack_expect_insert(expect); | |
ac3247ba | 1043 | ip_conntrack_expect_event(IPEXP_NEW, expect); |
1da177e4 LT |
1044 | ret = 0; |
1045 | out: | |
e45b1be8 | 1046 | write_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
1047 | return ret; |
1048 | } | |
1049 | ||
1050 | /* Alter reply tuple (maybe alter helper). This is for NAT, and is | |
1051 | implicitly racy: see __ip_conntrack_confirm */ | |
1052 | void ip_conntrack_alter_reply(struct ip_conntrack *conntrack, | |
1053 | const struct ip_conntrack_tuple *newreply) | |
1054 | { | |
e45b1be8 | 1055 | write_lock_bh(&ip_conntrack_lock); |
1da177e4 LT |
1056 | /* Should be unconfirmed, so not in hash table yet */ |
1057 | IP_NF_ASSERT(!is_confirmed(conntrack)); | |
1058 | ||
1059 | DEBUGP("Altering reply tuple of %p to ", conntrack); | |
1060 | DUMP_TUPLE(newreply); | |
1061 | ||
1062 | conntrack->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply; | |
1063 | if (!conntrack->master && conntrack->expecting == 0) | |
080774a2 | 1064 | conntrack->helper = __ip_conntrack_helper_find(newreply); |
e45b1be8 | 1065 | write_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
1066 | } |
1067 | ||
1068 | int ip_conntrack_helper_register(struct ip_conntrack_helper *me) | |
1069 | { | |
1070 | BUG_ON(me->timeout == 0); | |
e45b1be8 | 1071 | write_lock_bh(&ip_conntrack_lock); |
1da177e4 | 1072 | list_prepend(&helpers, me); |
e45b1be8 | 1073 | write_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
1074 | |
1075 | return 0; | |
1076 | } | |
1077 | ||
080774a2 HW |
1078 | struct ip_conntrack_helper * |
1079 | __ip_conntrack_helper_find_byname(const char *name) | |
1080 | { | |
1081 | struct ip_conntrack_helper *h; | |
1082 | ||
1083 | list_for_each_entry(h, &helpers, list) { | |
1084 | if (!strcmp(h->name, name)) | |
1085 | return h; | |
1086 | } | |
1087 | ||
1088 | return NULL; | |
1089 | } | |
1090 | ||
1da177e4 LT |
1091 | static inline int unhelp(struct ip_conntrack_tuple_hash *i, |
1092 | const struct ip_conntrack_helper *me) | |
1093 | { | |
ac3247ba HW |
1094 | if (tuplehash_to_ctrack(i)->helper == me) { |
1095 | ip_conntrack_event(IPCT_HELPER, tuplehash_to_ctrack(i)); | |
1da177e4 | 1096 | tuplehash_to_ctrack(i)->helper = NULL; |
ac3247ba | 1097 | } |
1da177e4 LT |
1098 | return 0; |
1099 | } | |
1100 | ||
1101 | void ip_conntrack_helper_unregister(struct ip_conntrack_helper *me) | |
1102 | { | |
1103 | unsigned int i; | |
1104 | struct ip_conntrack_expect *exp, *tmp; | |
1105 | ||
1106 | /* Need write lock here, to delete helper. */ | |
e45b1be8 | 1107 | write_lock_bh(&ip_conntrack_lock); |
1da177e4 LT |
1108 | LIST_DELETE(&helpers, me); |
1109 | ||
1110 | /* Get rid of expectations */ | |
1111 | list_for_each_entry_safe(exp, tmp, &ip_conntrack_expect_list, list) { | |
1112 | if (exp->master->helper == me && del_timer(&exp->timeout)) { | |
1113 | unlink_expect(exp); | |
4acdbdbe | 1114 | ip_conntrack_expect_put(exp); |
1da177e4 LT |
1115 | } |
1116 | } | |
1117 | /* Get rid of expecteds, set helpers to NULL. */ | |
1118 | LIST_FIND_W(&unconfirmed, unhelp, struct ip_conntrack_tuple_hash*, me); | |
1119 | for (i = 0; i < ip_conntrack_htable_size; i++) | |
1120 | LIST_FIND_W(&ip_conntrack_hash[i], unhelp, | |
1121 | struct ip_conntrack_tuple_hash *, me); | |
e45b1be8 | 1122 | write_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
1123 | |
1124 | /* Someone could be still looking at the helper in a bh. */ | |
1125 | synchronize_net(); | |
1126 | } | |
1127 | ||
1128 | static inline void ct_add_counters(struct ip_conntrack *ct, | |
1129 | enum ip_conntrack_info ctinfo, | |
1130 | const struct sk_buff *skb) | |
1131 | { | |
1132 | #ifdef CONFIG_IP_NF_CT_ACCT | |
1133 | if (skb) { | |
1134 | ct->counters[CTINFO2DIR(ctinfo)].packets++; | |
1135 | ct->counters[CTINFO2DIR(ctinfo)].bytes += | |
1136 | ntohs(skb->nh.iph->tot_len); | |
1137 | } | |
1138 | #endif | |
1139 | } | |
1140 | ||
1141 | /* Refresh conntrack for this many jiffies and do accounting (if skb != NULL) */ | |
1142 | void ip_ct_refresh_acct(struct ip_conntrack *ct, | |
1143 | enum ip_conntrack_info ctinfo, | |
1144 | const struct sk_buff *skb, | |
1145 | unsigned long extra_jiffies) | |
1146 | { | |
1147 | IP_NF_ASSERT(ct->timeout.data == (unsigned long)ct); | |
1148 | ||
1149 | /* If not in hash table, timer will not be active yet */ | |
1150 | if (!is_confirmed(ct)) { | |
1151 | ct->timeout.expires = extra_jiffies; | |
1152 | ct_add_counters(ct, ctinfo, skb); | |
1153 | } else { | |
e45b1be8 | 1154 | write_lock_bh(&ip_conntrack_lock); |
1da177e4 LT |
1155 | /* Need del_timer for race avoidance (may already be dying). */ |
1156 | if (del_timer(&ct->timeout)) { | |
1157 | ct->timeout.expires = jiffies + extra_jiffies; | |
1158 | add_timer(&ct->timeout); | |
ac3247ba | 1159 | ip_conntrack_event_cache(IPCT_REFRESH, skb); |
1da177e4 LT |
1160 | } |
1161 | ct_add_counters(ct, ctinfo, skb); | |
e45b1be8 | 1162 | write_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
1163 | } |
1164 | } | |
1165 | ||
080774a2 HW |
1166 | #if defined(CONFIG_IP_NF_CONNTRACK_NETLINK) || \ |
1167 | defined(CONFIG_IP_NF_CONNTRACK_NETLINK_MODULE) | |
1168 | /* Generic function for tcp/udp/sctp/dccp and alike. This needs to be | |
1169 | * in ip_conntrack_core, since we don't want the protocols to autoload | |
1170 | * or depend on ctnetlink */ | |
1171 | int ip_ct_port_tuple_to_nfattr(struct sk_buff *skb, | |
1172 | const struct ip_conntrack_tuple *tuple) | |
1173 | { | |
1174 | NFA_PUT(skb, CTA_PROTO_SRC_PORT, sizeof(u_int16_t), | |
1175 | &tuple->src.u.tcp.port); | |
1176 | NFA_PUT(skb, CTA_PROTO_DST_PORT, sizeof(u_int16_t), | |
1177 | &tuple->dst.u.tcp.port); | |
1178 | return 0; | |
1179 | ||
1180 | nfattr_failure: | |
1181 | return -1; | |
1182 | } | |
1183 | ||
1184 | int ip_ct_port_nfattr_to_tuple(struct nfattr *tb[], | |
1185 | struct ip_conntrack_tuple *t) | |
1186 | { | |
1187 | if (!tb[CTA_PROTO_SRC_PORT-1] || !tb[CTA_PROTO_DST_PORT-1]) | |
1188 | return -EINVAL; | |
1189 | ||
1190 | t->src.u.tcp.port = | |
1191 | *(u_int16_t *)NFA_DATA(tb[CTA_PROTO_SRC_PORT-1]); | |
1192 | t->dst.u.tcp.port = | |
1193 | *(u_int16_t *)NFA_DATA(tb[CTA_PROTO_DST_PORT-1]); | |
1194 | ||
1195 | return 0; | |
1196 | } | |
1197 | #endif | |
1198 | ||
1da177e4 LT |
1199 | /* Returns new sk_buff, or NULL */ |
1200 | struct sk_buff * | |
1201 | ip_ct_gather_frags(struct sk_buff *skb, u_int32_t user) | |
1202 | { | |
8be58932 | 1203 | skb_orphan(skb); |
1da177e4 LT |
1204 | |
1205 | local_bh_disable(); | |
1206 | skb = ip_defrag(skb, user); | |
1207 | local_bh_enable(); | |
1208 | ||
6869c4d8 | 1209 | if (skb) |
8be58932 | 1210 | ip_send_check(skb->nh.iph); |
1da177e4 LT |
1211 | return skb; |
1212 | } | |
1213 | ||
1214 | /* Used by ipt_REJECT. */ | |
1215 | static void ip_conntrack_attach(struct sk_buff *nskb, struct sk_buff *skb) | |
1216 | { | |
1217 | struct ip_conntrack *ct; | |
1218 | enum ip_conntrack_info ctinfo; | |
1219 | ||
1220 | /* This ICMP is in reverse direction to the packet which caused it */ | |
1221 | ct = ip_conntrack_get(skb, &ctinfo); | |
1222 | ||
1223 | if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) | |
1224 | ctinfo = IP_CT_RELATED + IP_CT_IS_REPLY; | |
1225 | else | |
1226 | ctinfo = IP_CT_RELATED; | |
1227 | ||
1228 | /* Attach to new skbuff, and increment count */ | |
1229 | nskb->nfct = &ct->ct_general; | |
1230 | nskb->nfctinfo = ctinfo; | |
1231 | nf_conntrack_get(nskb->nfct); | |
1232 | } | |
1233 | ||
1234 | static inline int | |
1235 | do_iter(const struct ip_conntrack_tuple_hash *i, | |
1236 | int (*iter)(struct ip_conntrack *i, void *data), | |
1237 | void *data) | |
1238 | { | |
1239 | return iter(tuplehash_to_ctrack(i), data); | |
1240 | } | |
1241 | ||
1242 | /* Bring out ya dead! */ | |
1243 | static struct ip_conntrack_tuple_hash * | |
1244 | get_next_corpse(int (*iter)(struct ip_conntrack *i, void *data), | |
1245 | void *data, unsigned int *bucket) | |
1246 | { | |
1247 | struct ip_conntrack_tuple_hash *h = NULL; | |
1248 | ||
e45b1be8 | 1249 | write_lock_bh(&ip_conntrack_lock); |
1da177e4 LT |
1250 | for (; *bucket < ip_conntrack_htable_size; (*bucket)++) { |
1251 | h = LIST_FIND_W(&ip_conntrack_hash[*bucket], do_iter, | |
1252 | struct ip_conntrack_tuple_hash *, iter, data); | |
1253 | if (h) | |
1254 | break; | |
1255 | } | |
1256 | if (!h) | |
1257 | h = LIST_FIND_W(&unconfirmed, do_iter, | |
1258 | struct ip_conntrack_tuple_hash *, iter, data); | |
1259 | if (h) | |
1260 | atomic_inc(&tuplehash_to_ctrack(h)->ct_general.use); | |
e45b1be8 | 1261 | write_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
1262 | |
1263 | return h; | |
1264 | } | |
1265 | ||
1266 | void | |
1267 | ip_ct_iterate_cleanup(int (*iter)(struct ip_conntrack *i, void *), void *data) | |
1268 | { | |
1269 | struct ip_conntrack_tuple_hash *h; | |
1270 | unsigned int bucket = 0; | |
1271 | ||
1272 | while ((h = get_next_corpse(iter, data, &bucket)) != NULL) { | |
1273 | struct ip_conntrack *ct = tuplehash_to_ctrack(h); | |
1274 | /* Time to push up daises... */ | |
1275 | if (del_timer(&ct->timeout)) | |
1276 | death_by_timeout((unsigned long)ct); | |
1277 | /* ... else the timer will get him soon. */ | |
1278 | ||
1279 | ip_conntrack_put(ct); | |
1280 | } | |
ac3247ba HW |
1281 | |
1282 | #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS | |
1283 | { | |
1284 | /* we need to deliver all cached events in order to drop | |
1285 | * the reference counts */ | |
1286 | int cpu; | |
1287 | for_each_cpu(cpu) { | |
1288 | struct ip_conntrack_ecache *ecache = | |
1289 | &per_cpu(ip_conntrack_ecache, cpu); | |
1290 | if (ecache->ct) { | |
1291 | __ip_ct_deliver_cached_events(ecache); | |
1292 | ip_conntrack_put(ecache->ct); | |
1293 | ecache->ct = NULL; | |
1294 | } | |
1295 | } | |
1296 | } | |
1297 | #endif | |
1da177e4 LT |
1298 | } |
1299 | ||
1300 | /* Fast function for those who don't want to parse /proc (and I don't | |
1301 | blame them). */ | |
1302 | /* Reversing the socket's dst/src point of view gives us the reply | |
1303 | mapping. */ | |
1304 | static int | |
1305 | getorigdst(struct sock *sk, int optval, void __user *user, int *len) | |
1306 | { | |
1307 | struct inet_sock *inet = inet_sk(sk); | |
1308 | struct ip_conntrack_tuple_hash *h; | |
1309 | struct ip_conntrack_tuple tuple; | |
1310 | ||
1311 | IP_CT_TUPLE_U_BLANK(&tuple); | |
1312 | tuple.src.ip = inet->rcv_saddr; | |
1313 | tuple.src.u.tcp.port = inet->sport; | |
1314 | tuple.dst.ip = inet->daddr; | |
1315 | tuple.dst.u.tcp.port = inet->dport; | |
1316 | tuple.dst.protonum = IPPROTO_TCP; | |
1317 | ||
1318 | /* We only do TCP at the moment: is there a better way? */ | |
1319 | if (strcmp(sk->sk_prot->name, "TCP")) { | |
1320 | DEBUGP("SO_ORIGINAL_DST: Not a TCP socket\n"); | |
1321 | return -ENOPROTOOPT; | |
1322 | } | |
1323 | ||
1324 | if ((unsigned int) *len < sizeof(struct sockaddr_in)) { | |
1325 | DEBUGP("SO_ORIGINAL_DST: len %u not %u\n", | |
1326 | *len, sizeof(struct sockaddr_in)); | |
1327 | return -EINVAL; | |
1328 | } | |
1329 | ||
1330 | h = ip_conntrack_find_get(&tuple, NULL); | |
1331 | if (h) { | |
1332 | struct sockaddr_in sin; | |
1333 | struct ip_conntrack *ct = tuplehash_to_ctrack(h); | |
1334 | ||
1335 | sin.sin_family = AF_INET; | |
1336 | sin.sin_port = ct->tuplehash[IP_CT_DIR_ORIGINAL] | |
1337 | .tuple.dst.u.tcp.port; | |
1338 | sin.sin_addr.s_addr = ct->tuplehash[IP_CT_DIR_ORIGINAL] | |
1339 | .tuple.dst.ip; | |
1340 | ||
1341 | DEBUGP("SO_ORIGINAL_DST: %u.%u.%u.%u %u\n", | |
1342 | NIPQUAD(sin.sin_addr.s_addr), ntohs(sin.sin_port)); | |
1343 | ip_conntrack_put(ct); | |
1344 | if (copy_to_user(user, &sin, sizeof(sin)) != 0) | |
1345 | return -EFAULT; | |
1346 | else | |
1347 | return 0; | |
1348 | } | |
1349 | DEBUGP("SO_ORIGINAL_DST: Can't find %u.%u.%u.%u/%u-%u.%u.%u.%u/%u.\n", | |
1350 | NIPQUAD(tuple.src.ip), ntohs(tuple.src.u.tcp.port), | |
1351 | NIPQUAD(tuple.dst.ip), ntohs(tuple.dst.u.tcp.port)); | |
1352 | return -ENOENT; | |
1353 | } | |
1354 | ||
1355 | static struct nf_sockopt_ops so_getorigdst = { | |
1356 | .pf = PF_INET, | |
1357 | .get_optmin = SO_ORIGINAL_DST, | |
1358 | .get_optmax = SO_ORIGINAL_DST+1, | |
1359 | .get = &getorigdst, | |
1360 | }; | |
1361 | ||
1362 | static int kill_all(struct ip_conntrack *i, void *data) | |
1363 | { | |
1364 | return 1; | |
1365 | } | |
1366 | ||
1367 | static void free_conntrack_hash(void) | |
1368 | { | |
1369 | if (ip_conntrack_vmalloc) | |
1370 | vfree(ip_conntrack_hash); | |
1371 | else | |
1372 | free_pages((unsigned long)ip_conntrack_hash, | |
1373 | get_order(sizeof(struct list_head) | |
1374 | * ip_conntrack_htable_size)); | |
1375 | } | |
1376 | ||
080774a2 | 1377 | void ip_conntrack_flush() |
1da177e4 | 1378 | { |
1da177e4 LT |
1379 | /* This makes sure all current packets have passed through |
1380 | netfilter framework. Roll on, two-stage module | |
1381 | delete... */ | |
1382 | synchronize_net(); | |
080774a2 | 1383 | |
1da177e4 LT |
1384 | i_see_dead_people: |
1385 | ip_ct_iterate_cleanup(kill_all, NULL); | |
1386 | if (atomic_read(&ip_conntrack_count) != 0) { | |
1387 | schedule(); | |
1388 | goto i_see_dead_people; | |
1389 | } | |
21f930e4 PM |
1390 | /* wait until all references to ip_conntrack_untracked are dropped */ |
1391 | while (atomic_read(&ip_conntrack_untracked.ct_general.use) > 1) | |
1392 | schedule(); | |
080774a2 | 1393 | } |
1da177e4 | 1394 | |
080774a2 HW |
1395 | /* Mishearing the voices in his head, our hero wonders how he's |
1396 | supposed to kill the mall. */ | |
1397 | void ip_conntrack_cleanup(void) | |
1398 | { | |
1399 | ip_ct_attach = NULL; | |
1400 | ip_conntrack_flush(); | |
1da177e4 LT |
1401 | kmem_cache_destroy(ip_conntrack_cachep); |
1402 | kmem_cache_destroy(ip_conntrack_expect_cachep); | |
1403 | free_conntrack_hash(); | |
1404 | nf_unregister_sockopt(&so_getorigdst); | |
1405 | } | |
1406 | ||
1407 | static int hashsize; | |
1408 | module_param(hashsize, int, 0400); | |
1409 | ||
1410 | int __init ip_conntrack_init(void) | |
1411 | { | |
1412 | unsigned int i; | |
1413 | int ret; | |
1414 | ||
1415 | /* Idea from tcp.c: use 1/16384 of memory. On i386: 32MB | |
1416 | * machine has 256 buckets. >= 1GB machines have 8192 buckets. */ | |
1417 | if (hashsize) { | |
1418 | ip_conntrack_htable_size = hashsize; | |
1419 | } else { | |
1420 | ip_conntrack_htable_size | |
1421 | = (((num_physpages << PAGE_SHIFT) / 16384) | |
1422 | / sizeof(struct list_head)); | |
1423 | if (num_physpages > (1024 * 1024 * 1024 / PAGE_SIZE)) | |
1424 | ip_conntrack_htable_size = 8192; | |
1425 | if (ip_conntrack_htable_size < 16) | |
1426 | ip_conntrack_htable_size = 16; | |
1427 | } | |
1428 | ip_conntrack_max = 8 * ip_conntrack_htable_size; | |
1429 | ||
1430 | printk("ip_conntrack version %s (%u buckets, %d max)" | |
1431 | " - %Zd bytes per conntrack\n", IP_CONNTRACK_VERSION, | |
1432 | ip_conntrack_htable_size, ip_conntrack_max, | |
1433 | sizeof(struct ip_conntrack)); | |
1434 | ||
1435 | ret = nf_register_sockopt(&so_getorigdst); | |
1436 | if (ret != 0) { | |
1437 | printk(KERN_ERR "Unable to register netfilter socket option\n"); | |
1438 | return ret; | |
1439 | } | |
1440 | ||
1441 | /* AK: the hash table is twice as big than needed because it | |
1442 | uses list_head. it would be much nicer to caches to use a | |
1443 | single pointer list head here. */ | |
1444 | ip_conntrack_vmalloc = 0; | |
1445 | ip_conntrack_hash | |
1446 | =(void*)__get_free_pages(GFP_KERNEL, | |
1447 | get_order(sizeof(struct list_head) | |
1448 | *ip_conntrack_htable_size)); | |
1449 | if (!ip_conntrack_hash) { | |
1450 | ip_conntrack_vmalloc = 1; | |
1451 | printk(KERN_WARNING "ip_conntrack: falling back to vmalloc.\n"); | |
1452 | ip_conntrack_hash = vmalloc(sizeof(struct list_head) | |
1453 | * ip_conntrack_htable_size); | |
1454 | } | |
1455 | if (!ip_conntrack_hash) { | |
1456 | printk(KERN_ERR "Unable to create ip_conntrack_hash\n"); | |
1457 | goto err_unreg_sockopt; | |
1458 | } | |
1459 | ||
1460 | ip_conntrack_cachep = kmem_cache_create("ip_conntrack", | |
1461 | sizeof(struct ip_conntrack), 0, | |
1462 | 0, NULL, NULL); | |
1463 | if (!ip_conntrack_cachep) { | |
1464 | printk(KERN_ERR "Unable to create ip_conntrack slab cache\n"); | |
1465 | goto err_free_hash; | |
1466 | } | |
1467 | ||
1468 | ip_conntrack_expect_cachep = kmem_cache_create("ip_conntrack_expect", | |
1469 | sizeof(struct ip_conntrack_expect), | |
1470 | 0, 0, NULL, NULL); | |
1471 | if (!ip_conntrack_expect_cachep) { | |
1472 | printk(KERN_ERR "Unable to create ip_expect slab cache\n"); | |
1473 | goto err_free_conntrack_slab; | |
1474 | } | |
1475 | ||
1476 | /* Don't NEED lock here, but good form anyway. */ | |
e45b1be8 | 1477 | write_lock_bh(&ip_conntrack_lock); |
1da177e4 LT |
1478 | for (i = 0; i < MAX_IP_CT_PROTO; i++) |
1479 | ip_ct_protos[i] = &ip_conntrack_generic_protocol; | |
1480 | /* Sew in builtin protocols. */ | |
1481 | ip_ct_protos[IPPROTO_TCP] = &ip_conntrack_protocol_tcp; | |
1482 | ip_ct_protos[IPPROTO_UDP] = &ip_conntrack_protocol_udp; | |
1483 | ip_ct_protos[IPPROTO_ICMP] = &ip_conntrack_protocol_icmp; | |
e45b1be8 | 1484 | write_unlock_bh(&ip_conntrack_lock); |
1da177e4 LT |
1485 | |
1486 | for (i = 0; i < ip_conntrack_htable_size; i++) | |
1487 | INIT_LIST_HEAD(&ip_conntrack_hash[i]); | |
1488 | ||
1489 | /* For use by ipt_REJECT */ | |
1490 | ip_ct_attach = ip_conntrack_attach; | |
1491 | ||
1492 | /* Set up fake conntrack: | |
1493 | - to never be deleted, not in any hashes */ | |
1494 | atomic_set(&ip_conntrack_untracked.ct_general.use, 1); | |
1495 | /* - and look it like as a confirmed connection */ | |
1496 | set_bit(IPS_CONFIRMED_BIT, &ip_conntrack_untracked.status); | |
1497 | ||
1498 | return ret; | |
1499 | ||
1500 | err_free_conntrack_slab: | |
1501 | kmem_cache_destroy(ip_conntrack_cachep); | |
1502 | err_free_hash: | |
1503 | free_conntrack_hash(); | |
1504 | err_unreg_sockopt: | |
1505 | nf_unregister_sockopt(&so_getorigdst); | |
1506 | ||
1507 | return -ENOMEM; | |
1508 | } |