2 * Connection state tracking for netfilter. This is separated from,
3 * but required by, the (future) NAT layer; it can also be used by an iptables
6 * 16 Dec 2003: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
7 * - generalize L3 protocol dependent part.
9 * Derived from include/linux/netfiter_ipv4/ip_conntrack.h
12 #ifndef _NF_CONNTRACK_H
13 #define _NF_CONNTRACK_H
15 #include <linux/netfilter/nf_conntrack_common.h>
18 #include <linux/config.h>
19 #include <linux/bitops.h>
20 #include <linux/compiler.h>
21 #include <asm/atomic.h>
23 #include <linux/netfilter/nf_conntrack_tcp.h>
24 #include <linux/netfilter/nf_conntrack_sctp.h>
25 #include <net/netfilter/ipv4/nf_conntrack_icmp.h>
26 #include <net/netfilter/ipv6/nf_conntrack_icmpv6.h>
28 #include <net/netfilter/nf_conntrack_tuple.h>
30 /* per conntrack: protocol private data */
31 union nf_conntrack_proto
{
32 /* insert conntrack proto private data here */
33 struct ip_ct_sctp sctp
;
35 struct ip_ct_icmp icmp
;
36 struct nf_ct_icmpv6 icmpv6
;
39 union nf_conntrack_expect_proto
{
40 /* insert expect proto private data here */
43 /* Add protocol helper include file here */
44 #include <linux/netfilter/nf_conntrack_ftp.h>
46 /* per conntrack: application helper private data */
47 union nf_conntrack_help
{
48 /* insert conntrack helper private data (master) here */
49 struct ip_ct_ftp_master ct_ftp_info
;
52 #include <linux/types.h>
53 #include <linux/skbuff.h>
55 #ifdef CONFIG_NETFILTER_DEBUG
56 #define NF_CT_ASSERT(x) \
59 /* Wooah! I'm tripping my conntrack in a frenzy of \
61 printk("NF_CT_ASSERT: %s:%i(%s)\n", \
62 __FILE__, __LINE__, __FUNCTION__); \
65 #define NF_CT_ASSERT(x)
68 struct nf_conntrack_helper
;
70 /* nf_conn feature for connections that have a helper */
73 struct nf_conntrack_helper
*helper
;
75 union nf_conntrack_help help
;
77 /* Current number of expected connections */
78 unsigned int expecting
;
82 #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
85 /* Usage count in here is 1 for hash table/destruct timer, 1 per skb,
86 plus 1 for any connection(s) we are `master' for */
87 struct nf_conntrack ct_general
;
89 /* XXX should I move this to the tail ? - Y.K */
90 /* These are my tuples; original and reply */
91 struct nf_conntrack_tuple_hash tuplehash
[IP_CT_DIR_MAX
];
93 /* Have we seen traffic both ways yet? (bitset) */
96 /* If we were expected by an expectation, this will be it */
97 struct nf_conn
*master
;
99 /* Timer function; drops refcnt when it goes off. */
100 struct timer_list timeout
;
102 #ifdef CONFIG_NF_CT_ACCT
103 /* Accounting Information (same cache line as other written members) */
104 struct ip_conntrack_counter counters
[IP_CT_DIR_MAX
];
107 /* Unique ID that identifies this conntrack*/
110 /* features - nat, helper, ... used by allocating system */
113 #if defined(CONFIG_NF_CONNTRACK_MARK)
117 /* Storage reserved for other modules: */
118 union nf_conntrack_proto proto
;
120 /* features dynamically at the end: helper, nat (both optional) */
124 struct nf_conntrack_expect
126 /* Internal linked list (global expectation list) */
127 struct list_head list
;
129 /* We expect this tuple, with the following mask */
130 struct nf_conntrack_tuple tuple
, mask
;
132 /* Function to call after setup and insertion */
133 void (*expectfn
)(struct nf_conn
*new,
134 struct nf_conntrack_expect
*this);
136 /* The conntrack of the master connection */
137 struct nf_conn
*master
;
139 /* Timer function; deletes the expectation. */
140 struct timer_list timeout
;
151 #ifdef CONFIG_NF_NAT_NEEDED
152 /* This is the original per-proto part, used to map the
153 * expected connection the way the recipient expects. */
154 union nf_conntrack_manip_proto saved_proto
;
155 /* Direction relative to the master connection. */
156 enum ip_conntrack_dir dir
;
160 #define NF_CT_EXPECT_PERMANENT 0x1
162 static inline struct nf_conn
*
163 nf_ct_tuplehash_to_ctrack(const struct nf_conntrack_tuple_hash
*hash
)
165 return container_of(hash
, struct nf_conn
,
166 tuplehash
[hash
->tuple
.dst
.dir
]);
169 /* get master conntrack via master expectation */
170 #define master_ct(conntr) (conntr->master)
172 /* Alter reply tuple (maybe alter helper). */
174 nf_conntrack_alter_reply(struct nf_conn
*conntrack
,
175 const struct nf_conntrack_tuple
*newreply
);
177 /* Is this tuple taken? (ignoring any belonging to the given
180 nf_conntrack_tuple_taken(const struct nf_conntrack_tuple
*tuple
,
181 const struct nf_conn
*ignored_conntrack
);
183 /* Return conntrack_info and tuple hash for given skb. */
184 static inline struct nf_conn
*
185 nf_ct_get(const struct sk_buff
*skb
, enum ip_conntrack_info
*ctinfo
)
187 *ctinfo
= skb
->nfctinfo
;
188 return (struct nf_conn
*)skb
->nfct
;
191 /* decrement reference count on a conntrack */
192 static inline void nf_ct_put(struct nf_conn
*ct
)
195 nf_conntrack_put(&ct
->ct_general
);
198 /* Protocol module loading */
199 extern int nf_ct_l3proto_try_module_get(unsigned short l3proto
);
200 extern void nf_ct_l3proto_module_put(unsigned short l3proto
);
202 extern struct nf_conntrack_tuple_hash
*
203 __nf_conntrack_find(const struct nf_conntrack_tuple
*tuple
,
204 const struct nf_conn
*ignored_conntrack
);
206 extern void nf_conntrack_hash_insert(struct nf_conn
*ct
);
208 extern struct nf_conntrack_expect
*
209 __nf_conntrack_expect_find(const struct nf_conntrack_tuple
*tuple
);
211 extern struct nf_conntrack_expect
*
212 nf_conntrack_expect_find(const struct nf_conntrack_tuple
*tuple
);
214 extern void nf_ct_unlink_expect(struct nf_conntrack_expect
*exp
);
216 extern void nf_ct_remove_expectations(struct nf_conn
*ct
);
218 extern void nf_conntrack_flush(void);
220 extern struct nf_conntrack_helper
*
221 nf_ct_helper_find_get( const struct nf_conntrack_tuple
*tuple
);
222 extern void nf_ct_helper_put(struct nf_conntrack_helper
*helper
);
224 extern struct nf_conntrack_helper
*
225 __nf_conntrack_helper_find_byname(const char *name
);
227 extern int nf_ct_invert_tuplepr(struct nf_conntrack_tuple
*inverse
,
228 const struct nf_conntrack_tuple
*orig
);
230 extern void __nf_ct_refresh_acct(struct nf_conn
*ct
,
231 enum ip_conntrack_info ctinfo
,
232 const struct sk_buff
*skb
,
233 unsigned long extra_jiffies
,
236 /* Refresh conntrack for this many jiffies and do accounting */
237 static inline void nf_ct_refresh_acct(struct nf_conn
*ct
,
238 enum ip_conntrack_info ctinfo
,
239 const struct sk_buff
*skb
,
240 unsigned long extra_jiffies
)
242 __nf_ct_refresh_acct(ct
, ctinfo
, skb
, extra_jiffies
, 1);
245 /* Refresh conntrack for this many jiffies */
246 static inline void nf_ct_refresh(struct nf_conn
*ct
,
247 const struct sk_buff
*skb
,
248 unsigned long extra_jiffies
)
250 __nf_ct_refresh_acct(ct
, 0, skb
, extra_jiffies
, 0);
253 /* These are for NAT. Icky. */
254 /* Update TCP window tracking data when NAT mangles the packet */
255 extern void nf_conntrack_tcp_update(struct sk_buff
*skb
,
256 unsigned int dataoff
,
257 struct nf_conn
*conntrack
,
260 /* Call me when a conntrack is destroyed. */
261 extern void (*nf_conntrack_destroyed
)(struct nf_conn
*conntrack
);
263 /* Fake conntrack entry for untracked connections */
264 extern struct nf_conn nf_conntrack_untracked
;
266 extern int nf_ct_no_defrag
;
268 /* Iterate over all conntracks: if iter returns true, it's deleted. */
270 nf_ct_iterate_cleanup(int (*iter
)(struct nf_conn
*i
, void *data
), void *data
);
271 extern void nf_conntrack_free(struct nf_conn
*ct
);
272 extern struct nf_conn
*
273 nf_conntrack_alloc(const struct nf_conntrack_tuple
*orig
,
274 const struct nf_conntrack_tuple
*repl
);
276 /* It's confirmed if it is, or has been in the hash table. */
277 static inline int nf_ct_is_confirmed(struct nf_conn
*ct
)
279 return test_bit(IPS_CONFIRMED_BIT
, &ct
->status
);
282 static inline int nf_ct_is_dying(struct nf_conn
*ct
)
284 return test_bit(IPS_DYING_BIT
, &ct
->status
);
287 extern unsigned int nf_conntrack_htable_size
;
289 #define NF_CT_STAT_INC(count) (__get_cpu_var(nf_conntrack_stat).count++)
291 #ifdef CONFIG_NF_CONNTRACK_EVENTS
292 #include <linux/notifier.h>
293 #include <linux/interrupt.h>
295 struct nf_conntrack_ecache
{
299 DECLARE_PER_CPU(struct nf_conntrack_ecache
, nf_conntrack_ecache
);
301 #define CONNTRACK_ECACHE(x) (__get_cpu_var(nf_conntrack_ecache).x)
303 extern struct atomic_notifier_head nf_conntrack_chain
;
304 extern struct atomic_notifier_head nf_conntrack_expect_chain
;
306 static inline int nf_conntrack_register_notifier(struct notifier_block
*nb
)
308 return atomic_notifier_chain_register(&nf_conntrack_chain
, nb
);
311 static inline int nf_conntrack_unregister_notifier(struct notifier_block
*nb
)
313 return atomic_notifier_chain_unregister(&nf_conntrack_chain
, nb
);
317 nf_conntrack_expect_register_notifier(struct notifier_block
*nb
)
319 return atomic_notifier_chain_register(&nf_conntrack_expect_chain
, nb
);
323 nf_conntrack_expect_unregister_notifier(struct notifier_block
*nb
)
325 return atomic_notifier_chain_unregister(&nf_conntrack_expect_chain
,
329 extern void nf_ct_deliver_cached_events(const struct nf_conn
*ct
);
330 extern void __nf_ct_event_cache_init(struct nf_conn
*ct
);
333 nf_conntrack_event_cache(enum ip_conntrack_events event
,
334 const struct sk_buff
*skb
)
336 struct nf_conn
*ct
= (struct nf_conn
*)skb
->nfct
;
337 struct nf_conntrack_ecache
*ecache
;
340 ecache
= &__get_cpu_var(nf_conntrack_ecache
);
341 if (ct
!= ecache
->ct
)
342 __nf_ct_event_cache_init(ct
);
343 ecache
->events
|= event
;
347 static inline void nf_conntrack_event(enum ip_conntrack_events event
,
350 if (nf_ct_is_confirmed(ct
) && !nf_ct_is_dying(ct
))
351 atomic_notifier_call_chain(&nf_conntrack_chain
, event
, ct
);
355 nf_conntrack_expect_event(enum ip_conntrack_expect_events event
,
356 struct nf_conntrack_expect
*exp
)
358 atomic_notifier_call_chain(&nf_conntrack_expect_chain
, event
, exp
);
360 #else /* CONFIG_NF_CONNTRACK_EVENTS */
361 static inline void nf_conntrack_event_cache(enum ip_conntrack_events event
,
362 const struct sk_buff
*skb
) {}
363 static inline void nf_conntrack_event(enum ip_conntrack_events event
,
364 struct nf_conn
*ct
) {}
365 static inline void nf_ct_deliver_cached_events(const struct nf_conn
*ct
) {}
367 nf_conntrack_expect_event(enum ip_conntrack_expect_events event
,
368 struct nf_conntrack_expect
*exp
) {}
369 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
371 /* no helper, no nat */
372 #define NF_CT_F_BASIC 0
374 #define NF_CT_F_HELP 1
376 #define NF_CT_F_NAT 2
377 #define NF_CT_F_NUM 4
380 nf_conntrack_register_cache(u_int32_t features
, const char *name
, size_t size
);
382 nf_conntrack_unregister_cache(u_int32_t features
);
384 /* valid combinations:
385 * basic: nf_conn, nf_conn .. nf_conn_help
386 * nat: nf_conn .. nf_conn_nat, nf_conn .. nf_conn_nat, nf_conn help
388 static inline struct nf_conn_help
*nfct_help(const struct nf_conn
*ct
)
390 unsigned int offset
= sizeof(struct nf_conn
);
392 if (!(ct
->features
& NF_CT_F_HELP
))
395 return (struct nf_conn_help
*) ((void *)ct
+ offset
);
398 #endif /* __KERNEL__ */
399 #endif /* _NF_CONNTRACK_H */