1 #ifndef _IP_CONNTRACK_H
2 #define _IP_CONNTRACK_H
3 /* Connection state tracking for netfilter. This is separated from,
4 but required by, the NAT layer; it can also be used by an iptables
8 /* Part of an established connection (either direction). */
11 /* Like NEW, but related to an existing connection, or ICMP error
12 (in either direction). */
15 /* Started a new connection to track (only
16 IP_CT_DIR_ORIGINAL); may be a retransmission. */
19 /* >= this indicates reply direction */
22 /* Number of distinct IP_CT types (no NEW in reply dirn). */
23 IP_CT_NUMBER = IP_CT_IS_REPLY * 2 - 1
26 /* Bitset representing status of connection. */
27 enum ip_conntrack_status {
28 /* It's an expected connection: bit 0 set. This bit never changed */
30 IPS_EXPECTED = (1 << IPS_EXPECTED_BIT),
32 /* We've seen packets both ways: bit 1 set. Can be set, not unset. */
33 IPS_SEEN_REPLY_BIT = 1,
34 IPS_SEEN_REPLY = (1 << IPS_SEEN_REPLY_BIT),
36 /* Conntrack should never be early-expired. */
38 IPS_ASSURED = (1 << IPS_ASSURED_BIT),
40 /* Connection is confirmed: originating packet has left box */
41 IPS_CONFIRMED_BIT = 3,
42 IPS_CONFIRMED = (1 << IPS_CONFIRMED_BIT),
44 /* Connection needs src nat in orig dir. This bit never changed. */
46 IPS_SRC_NAT = (1 << IPS_SRC_NAT_BIT),
48 /* Connection needs dst nat in orig dir. This bit never changed. */
50 IPS_DST_NAT = (1 << IPS_DST_NAT_BIT),
53 IPS_NAT_MASK = (IPS_DST_NAT | IPS_SRC_NAT),
55 /* Connection needs TCP sequence adjusted. */
56 IPS_SEQ_ADJUST_BIT = 6,
57 IPS_SEQ_ADJUST = (1 << IPS_SEQ_ADJUST_BIT),
59 /* NAT initialization bits. */
60 IPS_SRC_NAT_DONE_BIT = 7,
61 IPS_SRC_NAT_DONE = (1 << IPS_SRC_NAT_DONE_BIT),
63 IPS_DST_NAT_DONE_BIT = 8,
64 IPS_DST_NAT_DONE = (1 << IPS_DST_NAT_DONE_BIT),
67 IPS_NAT_DONE_MASK = (IPS_DST_NAT_DONE | IPS_SRC_NAT_DONE),
69 /* Connection is dying (removed from lists), can not be unset. */
71 IPS_DYING = (1 << IPS_DYING_BIT),
74 /* Connection tracking event bits */
75 enum ip_conntrack_events
79 IPCT_NEW = (1 << IPCT_NEW_BIT),
81 /* Expected connection */
83 IPCT_RELATED = (1 << IPCT_RELATED_BIT),
85 /* Destroyed conntrack */
87 IPCT_DESTROY = (1 << IPCT_DESTROY_BIT),
89 /* Timer has been refreshed */
91 IPCT_REFRESH = (1 << IPCT_REFRESH_BIT),
93 /* Status has changed */
95 IPCT_STATUS = (1 << IPCT_STATUS_BIT),
97 /* Update of protocol info */
98 IPCT_PROTOINFO_BIT = 5,
99 IPCT_PROTOINFO = (1 << IPCT_PROTOINFO_BIT),
101 /* Volatile protocol info */
102 IPCT_PROTOINFO_VOLATILE_BIT = 6,
103 IPCT_PROTOINFO_VOLATILE = (1 << IPCT_PROTOINFO_VOLATILE_BIT),
105 /* New helper for conntrack */
107 IPCT_HELPER = (1 << IPCT_HELPER_BIT),
109 /* Update of helper info */
110 IPCT_HELPINFO_BIT = 8,
111 IPCT_HELPINFO = (1 << IPCT_HELPINFO_BIT),
113 /* Volatile helper info */
114 IPCT_HELPINFO_VOLATILE_BIT = 9,
115 IPCT_HELPINFO_VOLATILE = (1 << IPCT_HELPINFO_VOLATILE_BIT),
118 IPCT_NATINFO_BIT = 10,
119 IPCT_NATINFO = (1 << IPCT_NATINFO_BIT),
121 /* Counter highest bit has been set */
122 IPCT_COUNTER_FILLING_BIT = 11,
123 IPCT_COUNTER_FILLING = (1 << IPCT_COUNTER_FILLING_BIT),
126 enum ip_conntrack_expect_events {
128 IPEXP_NEW = (1 << IPEXP_NEW_BIT),
132 #include <linux/config.h>
133 #include <linux/netfilter_ipv4/ip_conntrack_tuple.h>
134 #include <linux/bitops.h>
135 #include <linux/compiler.h>
136 #include <asm/atomic.h>
138 #include <linux/netfilter_ipv4/ip_conntrack_tcp.h>
139 #include <linux/netfilter_ipv4/ip_conntrack_icmp.h>
140 #include <linux/netfilter_ipv4/ip_conntrack_proto_gre.h>
141 #include <linux/netfilter_ipv4/ip_conntrack_sctp.h>
143 /* per conntrack: protocol private data */
144 union ip_conntrack_proto {
145 /* insert conntrack proto private data here */
146 struct ip_ct_gre gre;
147 struct ip_ct_sctp sctp;
148 struct ip_ct_tcp tcp;
149 struct ip_ct_icmp icmp;
152 union ip_conntrack_expect_proto {
153 /* insert expect proto private data here */
156 /* Add protocol helper include file here */
157 #include <linux/netfilter_ipv4/ip_conntrack_pptp.h>
158 #include <linux/netfilter_ipv4/ip_conntrack_amanda.h>
159 #include <linux/netfilter_ipv4/ip_conntrack_ftp.h>
160 #include <linux/netfilter_ipv4/ip_conntrack_irc.h>
162 /* per conntrack: application helper private data */
163 union ip_conntrack_help {
164 /* insert conntrack helper private data (master) here */
165 struct ip_ct_pptp_master ct_pptp_info;
166 struct ip_ct_ftp_master ct_ftp_info;
167 struct ip_ct_irc_master ct_irc_info;
170 #ifdef CONFIG_IP_NF_NAT_NEEDED
171 #include <linux/netfilter_ipv4/ip_nat.h>
172 #include <linux/netfilter_ipv4/ip_nat_pptp.h>
174 /* per conntrack: nat application helper private data */
175 union ip_conntrack_nat_help {
176 /* insert nat helper private data here */
177 struct ip_nat_pptp nat_pptp_info;
181 #include <linux/types.h>
182 #include <linux/skbuff.h>
184 #ifdef CONFIG_NETFILTER_DEBUG
185 #define IP_NF_ASSERT(x) \
188 /* Wooah! I'm tripping my conntrack in a frenzy of \
190 printk("NF_IP_ASSERT: %s:%i(%s)\n", \
191 __FILE__, __LINE__, __FUNCTION__); \
194 #define IP_NF_ASSERT(x)
197 struct ip_conntrack_counter
203 struct ip_conntrack_helper;
207 /* Usage count in here is 1 for hash table/destruct timer, 1 per skb,
208 plus 1 for any connection(s) we are `master' for */
209 struct nf_conntrack ct_general;
211 /* Have we seen traffic both ways yet? (bitset) */
212 unsigned long status;
214 /* Timer function; drops refcnt when it goes off. */
215 struct timer_list timeout;
217 #ifdef CONFIG_IP_NF_CT_ACCT
218 /* Accounting Information (same cache line as other written members) */
219 struct ip_conntrack_counter counters[IP_CT_DIR_MAX];
221 /* If we were expected by an expectation, this will be it */
222 struct ip_conntrack *master;
224 /* Current number of expected connections */
225 unsigned int expecting;
227 /* Unique ID that identifies this conntrack*/
230 /* Helper, if any. */
231 struct ip_conntrack_helper *helper;
233 /* Storage reserved for other modules: */
234 union ip_conntrack_proto proto;
236 union ip_conntrack_help help;
238 #ifdef CONFIG_IP_NF_NAT_NEEDED
240 struct ip_nat_info info;
241 union ip_conntrack_nat_help help;
242 #if defined(CONFIG_IP_NF_TARGET_MASQUERADE) || \
243 defined(CONFIG_IP_NF_TARGET_MASQUERADE_MODULE)
247 #endif /* CONFIG_IP_NF_NAT_NEEDED */
249 #if defined(CONFIG_IP_NF_CONNTRACK_MARK)
253 /* Traversed often, so hopefully in different cacheline to top */
254 /* These are my tuples; original and reply */
255 struct ip_conntrack_tuple_hash tuplehash[IP_CT_DIR_MAX];
258 struct ip_conntrack_expect
260 /* Internal linked list (global expectation list) */
261 struct list_head list;
263 /* We expect this tuple, with the following mask */
264 struct ip_conntrack_tuple tuple, mask;
266 /* Function to call after setup and insertion */
267 void (*expectfn)(struct ip_conntrack *new,
268 struct ip_conntrack_expect *this);
270 /* The conntrack of the master connection */
271 struct ip_conntrack *master;
273 /* Timer function; deletes the expectation. */
274 struct timer_list timeout;
285 #ifdef CONFIG_IP_NF_NAT_NEEDED
286 /* This is the original per-proto part, used to map the
287 * expected connection the way the recipient expects. */
288 union ip_conntrack_manip_proto saved_proto;
289 /* Direction relative to the master connection. */
290 enum ip_conntrack_dir dir;
294 #define IP_CT_EXPECT_PERMANENT 0x1
296 static inline struct ip_conntrack *
297 tuplehash_to_ctrack(const struct ip_conntrack_tuple_hash *hash)
299 return container_of(hash, struct ip_conntrack,
300 tuplehash[hash->tuple.dst.dir]);
303 /* get master conntrack via master expectation */
304 #define master_ct(conntr) (conntr->master)
306 /* Alter reply tuple (maybe alter helper). */
308 ip_conntrack_alter_reply(struct ip_conntrack *conntrack,
309 const struct ip_conntrack_tuple *newreply);
311 /* Is this tuple taken? (ignoring any belonging to the given
314 ip_conntrack_tuple_taken(const struct ip_conntrack_tuple *tuple,
315 const struct ip_conntrack *ignored_conntrack);
317 /* Return conntrack_info and tuple hash for given skb. */
318 static inline struct ip_conntrack *
319 ip_conntrack_get(const struct sk_buff *skb, enum ip_conntrack_info *ctinfo)
321 *ctinfo = skb->nfctinfo;
322 return (struct ip_conntrack *)skb->nfct;
325 /* decrement reference count on a conntrack */
327 ip_conntrack_put(struct ip_conntrack *ct)
330 nf_conntrack_put(&ct->ct_general);
333 /* call to create an explicit dependency on ip_conntrack. */
334 extern void need_ip_conntrack(void);
336 extern int invert_tuplepr(struct ip_conntrack_tuple *inverse,
337 const struct ip_conntrack_tuple *orig);
339 extern void __ip_ct_refresh_acct(struct ip_conntrack *ct,
340 enum ip_conntrack_info ctinfo,
341 const struct sk_buff *skb,
342 unsigned long extra_jiffies,
345 /* Refresh conntrack for this many jiffies and do accounting */
346 static inline void ip_ct_refresh_acct(struct ip_conntrack *ct,
347 enum ip_conntrack_info ctinfo,
348 const struct sk_buff *skb,
349 unsigned long extra_jiffies)
351 __ip_ct_refresh_acct(ct, ctinfo, skb, extra_jiffies, 1);
354 /* Refresh conntrack for this many jiffies */
355 static inline void ip_ct_refresh(struct ip_conntrack *ct,
356 const struct sk_buff *skb,
357 unsigned long extra_jiffies)
359 __ip_ct_refresh_acct(ct, 0, skb, extra_jiffies, 0);
362 /* These are for NAT. Icky. */
363 /* Update TCP window tracking data when NAT mangles the packet */
364 extern void ip_conntrack_tcp_update(struct sk_buff *skb,
365 struct ip_conntrack *conntrack,
366 enum ip_conntrack_dir dir);
368 /* Call me when a conntrack is destroyed. */
369 extern void (*ip_conntrack_destroyed)(struct ip_conntrack *conntrack);
371 /* Fake conntrack entry for untracked connections */
372 extern struct ip_conntrack ip_conntrack_untracked;
374 /* Returns new sk_buff, or NULL */
376 ip_ct_gather_frags(struct sk_buff *skb, u_int32_t user);
378 /* Iterate over all conntracks: if iter returns true, it's deleted. */
380 ip_ct_iterate_cleanup(int (*iter)(struct ip_conntrack *i, void *data),
383 extern struct ip_conntrack_helper *
384 __ip_conntrack_helper_find_byname(const char *);
385 extern struct ip_conntrack_helper *
386 ip_conntrack_helper_find_get(const struct ip_conntrack_tuple *tuple);
387 extern void ip_conntrack_helper_put(struct ip_conntrack_helper *helper);
389 extern struct ip_conntrack_protocol *
390 __ip_conntrack_proto_find(u_int8_t protocol);
391 extern struct ip_conntrack_protocol *
392 ip_conntrack_proto_find_get(u_int8_t protocol);
393 extern void ip_conntrack_proto_put(struct ip_conntrack_protocol *proto);
395 extern void ip_ct_remove_expectations(struct ip_conntrack *ct);
397 extern struct ip_conntrack *ip_conntrack_alloc(struct ip_conntrack_tuple *,
398 struct ip_conntrack_tuple *);
400 extern void ip_conntrack_free(struct ip_conntrack *ct);
402 extern void ip_conntrack_hash_insert(struct ip_conntrack *ct);
404 extern struct ip_conntrack_expect *
405 __ip_conntrack_expect_find(const struct ip_conntrack_tuple *tuple);
407 extern struct ip_conntrack_expect *
408 ip_conntrack_expect_find(const struct ip_conntrack_tuple *tuple);
410 extern struct ip_conntrack_tuple_hash *
411 __ip_conntrack_find(const struct ip_conntrack_tuple *tuple,
412 const struct ip_conntrack *ignored_conntrack);
414 extern void ip_conntrack_flush(void);
416 /* It's confirmed if it is, or has been in the hash table. */
417 static inline int is_confirmed(struct ip_conntrack *ct)
419 return test_bit(IPS_CONFIRMED_BIT, &ct->status);
422 static inline int is_dying(struct ip_conntrack *ct)
424 return test_bit(IPS_DYING_BIT, &ct->status);
427 extern unsigned int ip_conntrack_htable_size;
429 struct ip_conntrack_stat
431 unsigned int searched;
434 unsigned int invalid;
437 unsigned int delete_list;
439 unsigned int insert_failed;
441 unsigned int early_drop;
443 unsigned int expect_new;
444 unsigned int expect_create;
445 unsigned int expect_delete;
448 #define CONNTRACK_STAT_INC(count) (__get_cpu_var(ip_conntrack_stat).count++)
450 #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS
451 #include <linux/notifier.h>
452 #include <linux/interrupt.h>
454 struct ip_conntrack_ecache {
455 struct ip_conntrack *ct;
458 DECLARE_PER_CPU(struct ip_conntrack_ecache, ip_conntrack_ecache);
460 #define CONNTRACK_ECACHE(x) (__get_cpu_var(ip_conntrack_ecache).x)
462 extern struct notifier_block *ip_conntrack_chain;
463 extern struct notifier_block *ip_conntrack_expect_chain;
465 static inline int ip_conntrack_register_notifier(struct notifier_block *nb)
467 return notifier_chain_register(&ip_conntrack_chain, nb);
470 static inline int ip_conntrack_unregister_notifier(struct notifier_block *nb)
472 return notifier_chain_unregister(&ip_conntrack_chain, nb);
476 ip_conntrack_expect_register_notifier(struct notifier_block *nb)
478 return notifier_chain_register(&ip_conntrack_expect_chain, nb);
482 ip_conntrack_expect_unregister_notifier(struct notifier_block *nb)
484 return notifier_chain_unregister(&ip_conntrack_expect_chain, nb);
487 extern void ip_ct_deliver_cached_events(const struct ip_conntrack *ct);
488 extern void __ip_ct_event_cache_init(struct ip_conntrack *ct);
491 ip_conntrack_event_cache(enum ip_conntrack_events event,
492 const struct sk_buff *skb)
494 struct ip_conntrack *ct = (struct ip_conntrack *)skb->nfct;
495 struct ip_conntrack_ecache *ecache;
498 ecache = &__get_cpu_var(ip_conntrack_ecache);
499 if (ct != ecache->ct)
500 __ip_ct_event_cache_init(ct);
501 ecache->events |= event;
505 static inline void ip_conntrack_event(enum ip_conntrack_events event,
506 struct ip_conntrack *ct)
508 if (is_confirmed(ct) && !is_dying(ct))
509 notifier_call_chain(&ip_conntrack_chain, event, ct);
513 ip_conntrack_expect_event(enum ip_conntrack_expect_events event,
514 struct ip_conntrack_expect *exp)
516 notifier_call_chain(&ip_conntrack_expect_chain, event, exp);
518 #else /* CONFIG_IP_NF_CONNTRACK_EVENTS */
519 static inline void ip_conntrack_event_cache(enum ip_conntrack_events event,
520 const struct sk_buff *skb) {}
521 static inline void ip_conntrack_event(enum ip_conntrack_events event,
522 struct ip_conntrack *ct) {}
523 static inline void ip_ct_deliver_cached_events(const struct ip_conntrack *ct) {}
525 ip_conntrack_expect_event(enum ip_conntrack_expect_events event,
526 struct ip_conntrack_expect *exp) {}
527 #endif /* CONFIG_IP_NF_CONNTRACK_EVENTS */
529 #ifdef CONFIG_IP_NF_NAT_NEEDED
530 static inline int ip_nat_initialized(struct ip_conntrack *conntrack,
531 enum ip_nat_manip_type manip)
533 if (manip == IP_NAT_MANIP_SRC)
534 return test_bit(IPS_SRC_NAT_DONE_BIT, &conntrack->status);
535 return test_bit(IPS_DST_NAT_DONE_BIT, &conntrack->status);
537 #endif /* CONFIG_IP_NF_NAT_NEEDED */
539 #endif /* __KERNEL__ */
540 #endif /* _IP_CONNTRACK_H */