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),
122 enum ip_conntrack_expect_events {
124 IPEXP_NEW = (1 << IPEXP_NEW_BIT),
128 #include <linux/config.h>
129 #include <linux/netfilter_ipv4/ip_conntrack_tuple.h>
130 #include <linux/bitops.h>
131 #include <linux/compiler.h>
132 #include <asm/atomic.h>
134 #include <linux/netfilter_ipv4/ip_conntrack_tcp.h>
135 #include <linux/netfilter_ipv4/ip_conntrack_icmp.h>
136 #include <linux/netfilter_ipv4/ip_conntrack_sctp.h>
138 /* per conntrack: protocol private data */
139 union ip_conntrack_proto {
140 /* insert conntrack proto private data here */
141 struct ip_ct_sctp sctp;
142 struct ip_ct_tcp tcp;
143 struct ip_ct_icmp icmp;
146 union ip_conntrack_expect_proto {
147 /* insert expect proto private data here */
150 /* Add protocol helper include file here */
151 #include <linux/netfilter_ipv4/ip_conntrack_amanda.h>
152 #include <linux/netfilter_ipv4/ip_conntrack_ftp.h>
153 #include <linux/netfilter_ipv4/ip_conntrack_irc.h>
155 /* per conntrack: application helper private data */
156 union ip_conntrack_help {
157 /* insert conntrack helper private data (master) here */
158 struct ip_ct_ftp_master ct_ftp_info;
159 struct ip_ct_irc_master ct_irc_info;
162 #ifdef CONFIG_IP_NF_NAT_NEEDED
163 #include <linux/netfilter_ipv4/ip_nat.h>
166 #include <linux/types.h>
167 #include <linux/skbuff.h>
169 #ifdef CONFIG_NETFILTER_DEBUG
170 #define IP_NF_ASSERT(x) \
173 /* Wooah! I'm tripping my conntrack in a frenzy of \
175 printk("NF_IP_ASSERT: %s:%i(%s)\n", \
176 __FILE__, __LINE__, __FUNCTION__); \
179 #define IP_NF_ASSERT(x)
182 struct ip_conntrack_counter
188 struct ip_conntrack_helper;
192 /* Usage count in here is 1 for hash table/destruct timer, 1 per skb,
193 plus 1 for any connection(s) we are `master' for */
194 struct nf_conntrack ct_general;
196 /* Have we seen traffic both ways yet? (bitset) */
197 unsigned long status;
199 /* Timer function; drops refcnt when it goes off. */
200 struct timer_list timeout;
202 #ifdef CONFIG_IP_NF_CT_ACCT
203 /* Accounting Information (same cache line as other written members) */
204 struct ip_conntrack_counter counters[IP_CT_DIR_MAX];
206 /* If we were expected by an expectation, this will be it */
207 struct ip_conntrack *master;
209 /* Current number of expected connections */
210 unsigned int expecting;
212 /* Helper, if any. */
213 struct ip_conntrack_helper *helper;
215 /* Storage reserved for other modules: */
216 union ip_conntrack_proto proto;
218 union ip_conntrack_help help;
220 #ifdef CONFIG_IP_NF_NAT_NEEDED
222 struct ip_nat_info info;
223 #if defined(CONFIG_IP_NF_TARGET_MASQUERADE) || \
224 defined(CONFIG_IP_NF_TARGET_MASQUERADE_MODULE)
228 #endif /* CONFIG_IP_NF_NAT_NEEDED */
230 #if defined(CONFIG_IP_NF_CONNTRACK_MARK)
234 /* Traversed often, so hopefully in different cacheline to top */
235 /* These are my tuples; original and reply */
236 struct ip_conntrack_tuple_hash tuplehash[IP_CT_DIR_MAX];
239 struct ip_conntrack_expect
241 /* Internal linked list (global expectation list) */
242 struct list_head list;
244 /* We expect this tuple, with the following mask */
245 struct ip_conntrack_tuple tuple, mask;
247 /* Function to call after setup and insertion */
248 void (*expectfn)(struct ip_conntrack *new,
249 struct ip_conntrack_expect *this);
251 /* The conntrack of the master connection */
252 struct ip_conntrack *master;
254 /* Timer function; deletes the expectation. */
255 struct timer_list timeout;
260 #ifdef CONFIG_IP_NF_NAT_NEEDED
261 /* This is the original per-proto part, used to map the
262 * expected connection the way the recipient expects. */
263 union ip_conntrack_manip_proto saved_proto;
264 /* Direction relative to the master connection. */
265 enum ip_conntrack_dir dir;
269 static inline struct ip_conntrack *
270 tuplehash_to_ctrack(const struct ip_conntrack_tuple_hash *hash)
272 return container_of(hash, struct ip_conntrack,
273 tuplehash[hash->tuple.dst.dir]);
276 /* get master conntrack via master expectation */
277 #define master_ct(conntr) (conntr->master)
279 /* Alter reply tuple (maybe alter helper). */
281 ip_conntrack_alter_reply(struct ip_conntrack *conntrack,
282 const struct ip_conntrack_tuple *newreply);
284 /* Is this tuple taken? (ignoring any belonging to the given
287 ip_conntrack_tuple_taken(const struct ip_conntrack_tuple *tuple,
288 const struct ip_conntrack *ignored_conntrack);
290 /* Return conntrack_info and tuple hash for given skb. */
291 static inline struct ip_conntrack *
292 ip_conntrack_get(const struct sk_buff *skb, enum ip_conntrack_info *ctinfo)
294 *ctinfo = skb->nfctinfo;
295 return (struct ip_conntrack *)skb->nfct;
298 /* decrement reference count on a conntrack */
299 extern void ip_conntrack_put(struct ip_conntrack *ct);
301 /* call to create an explicit dependency on ip_conntrack. */
302 extern void need_ip_conntrack(void);
304 extern int invert_tuplepr(struct ip_conntrack_tuple *inverse,
305 const struct ip_conntrack_tuple *orig);
307 /* Refresh conntrack for this many jiffies */
308 extern void ip_ct_refresh_acct(struct ip_conntrack *ct,
309 enum ip_conntrack_info ctinfo,
310 const struct sk_buff *skb,
311 unsigned long extra_jiffies);
313 /* These are for NAT. Icky. */
314 /* Update TCP window tracking data when NAT mangles the packet */
315 extern void ip_conntrack_tcp_update(struct sk_buff *skb,
316 struct ip_conntrack *conntrack,
317 enum ip_conntrack_dir dir);
319 /* Call me when a conntrack is destroyed. */
320 extern void (*ip_conntrack_destroyed)(struct ip_conntrack *conntrack);
322 /* Fake conntrack entry for untracked connections */
323 extern struct ip_conntrack ip_conntrack_untracked;
325 /* Returns new sk_buff, or NULL */
327 ip_ct_gather_frags(struct sk_buff *skb, u_int32_t user);
329 /* Iterate over all conntracks: if iter returns true, it's deleted. */
331 ip_ct_iterate_cleanup(int (*iter)(struct ip_conntrack *i, void *data),
334 /* It's confirmed if it is, or has been in the hash table. */
335 static inline int is_confirmed(struct ip_conntrack *ct)
337 return test_bit(IPS_CONFIRMED_BIT, &ct->status);
340 static inline int is_dying(struct ip_conntrack *ct)
342 return test_bit(IPS_DYING_BIT, &ct->status);
345 extern unsigned int ip_conntrack_htable_size;
347 struct ip_conntrack_stat
349 unsigned int searched;
352 unsigned int invalid;
355 unsigned int delete_list;
357 unsigned int insert_failed;
359 unsigned int early_drop;
361 unsigned int expect_new;
362 unsigned int expect_create;
363 unsigned int expect_delete;
366 #define CONNTRACK_STAT_INC(count) (__get_cpu_var(ip_conntrack_stat).count++)
368 #ifdef CONFIG_IP_NF_CONNTRACK_EVENTS
369 #include <linux/notifier.h>
371 struct ip_conntrack_ecache {
372 struct ip_conntrack *ct;
375 DECLARE_PER_CPU(struct ip_conntrack_ecache, ip_conntrack_ecache);
377 #define CONNTRACK_ECACHE(x) (__get_cpu_var(ip_conntrack_ecache).x)
379 extern struct notifier_block *ip_conntrack_chain;
380 extern struct notifier_block *ip_conntrack_expect_chain;
382 static inline int ip_conntrack_register_notifier(struct notifier_block *nb)
384 return notifier_chain_register(&ip_conntrack_chain, nb);
387 static inline int ip_conntrack_unregister_notifier(struct notifier_block *nb)
389 return notifier_chain_unregister(&ip_conntrack_chain, nb);
393 ip_conntrack_expect_register_notifier(struct notifier_block *nb)
395 return notifier_chain_register(&ip_conntrack_expect_chain, nb);
399 ip_conntrack_expect_unregister_notifier(struct notifier_block *nb)
401 return notifier_chain_unregister(&ip_conntrack_expect_chain, nb);
405 ip_conntrack_event_cache(enum ip_conntrack_events event,
406 const struct sk_buff *skb)
408 struct ip_conntrack_ecache *ecache =
409 &__get_cpu_var(ip_conntrack_ecache);
411 if (unlikely((struct ip_conntrack *) skb->nfct != ecache->ct)) {
412 if (net_ratelimit()) {
413 printk(KERN_ERR "ctevent: skb->ct != ecache->ct !!!\n");
417 ecache->events |= event;
421 ip_conntrack_deliver_cached_events_for(const struct ip_conntrack *ct);
422 extern void ip_conntrack_event_cache_init(const struct sk_buff *skb);
424 static inline void ip_conntrack_event(enum ip_conntrack_events event,
425 struct ip_conntrack *ct)
427 if (is_confirmed(ct) && !is_dying(ct))
428 notifier_call_chain(&ip_conntrack_chain, event, ct);
432 ip_conntrack_expect_event(enum ip_conntrack_expect_events event,
433 struct ip_conntrack_expect *exp)
435 notifier_call_chain(&ip_conntrack_expect_chain, event, exp);
437 #else /* CONFIG_IP_NF_CONNTRACK_EVENTS */
438 static inline void ip_conntrack_event_cache(enum ip_conntrack_events event,
439 const struct sk_buff *skb) {}
440 static inline void ip_conntrack_event(enum ip_conntrack_events event,
441 struct ip_conntrack *ct) {}
442 static inline void ip_conntrack_deliver_cached_events_for(
443 struct ip_conntrack *ct) {}
444 static inline void ip_conntrack_event_cache_init(const struct sk_buff *skb) {}
446 ip_conntrack_expect_event(enum ip_conntrack_expect_events event,
447 struct ip_conntrack_expect *exp) {}
448 #endif /* CONFIG_IP_NF_CONNTRACK_EVENTS */
450 #ifdef CONFIG_IP_NF_NAT_NEEDED
451 static inline int ip_nat_initialized(struct ip_conntrack *conntrack,
452 enum ip_nat_manip_type manip)
454 if (manip == IP_NAT_MANIP_SRC)
455 return test_bit(IPS_SRC_NAT_DONE_BIT, &conntrack->status);
456 return test_bit(IPS_DST_NAT_DONE_BIT, &conntrack->status);
458 #endif /* CONFIG_IP_NF_NAT_NEEDED */
460 #endif /* __KERNEL__ */
461 #endif /* _IP_CONNTRACK_H */