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 #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
73 /* Usage count in here is 1 for hash table/destruct timer, 1 per skb,
74 plus 1 for any connection(s) we are `master' for */
75 struct nf_conntrack ct_general;
77 /* XXX should I move this to the tail ? - Y.K */
78 /* These are my tuples; original and reply */
79 struct nf_conntrack_tuple_hash tuplehash[IP_CT_DIR_MAX];
81 /* Have we seen traffic both ways yet? (bitset) */
84 /* Timer function; drops refcnt when it goes off. */
85 struct timer_list timeout;
87 #ifdef CONFIG_NF_CT_ACCT
88 /* Accounting Information (same cache line as other written members) */
89 struct ip_conntrack_counter counters[IP_CT_DIR_MAX];
91 /* If we were expected by an expectation, this will be it */
92 struct nf_conn *master;
94 /* Current number of expected connections */
95 unsigned int expecting;
98 struct nf_conntrack_helper *helper;
100 /* features - nat, helper, ... used by allocating system */
103 /* Storage reserved for other modules: */
105 union nf_conntrack_proto proto;
107 #if defined(CONFIG_NF_CONNTRACK_MARK)
111 /* These members are dynamically allocated. */
113 union nf_conntrack_help *help;
115 /* Layer 3 dependent members. (ex: NAT) */
117 struct nf_conntrack_ipv4 *ipv4;
122 struct nf_conntrack_expect
124 /* Internal linked list (global expectation list) */
125 struct list_head list;
127 /* We expect this tuple, with the following mask */
128 struct nf_conntrack_tuple tuple, mask;
130 /* Function to call after setup and insertion */
131 void (*expectfn)(struct nf_conn *new,
132 struct nf_conntrack_expect *this);
134 /* The conntrack of the master connection */
135 struct nf_conn *master;
137 /* Timer function; deletes the expectation. */
138 struct timer_list timeout;
146 #ifdef CONFIG_NF_NAT_NEEDED
147 /* This is the original per-proto part, used to map the
148 * expected connection the way the recipient expects. */
149 union nf_conntrack_manip_proto saved_proto;
150 /* Direction relative to the master connection. */
151 enum ip_conntrack_dir dir;
155 #define NF_CT_EXPECT_PERMANENT 0x1
157 static inline struct nf_conn *
158 nf_ct_tuplehash_to_ctrack(const struct nf_conntrack_tuple_hash *hash)
160 return container_of(hash, struct nf_conn,
161 tuplehash[hash->tuple.dst.dir]);
164 /* get master conntrack via master expectation */
165 #define master_ct(conntr) (conntr->master)
167 /* Alter reply tuple (maybe alter helper). */
169 nf_conntrack_alter_reply(struct nf_conn *conntrack,
170 const struct nf_conntrack_tuple *newreply);
172 /* Is this tuple taken? (ignoring any belonging to the given
175 nf_conntrack_tuple_taken(const struct nf_conntrack_tuple *tuple,
176 const struct nf_conn *ignored_conntrack);
178 /* Return conntrack_info and tuple hash for given skb. */
179 static inline struct nf_conn *
180 nf_ct_get(const struct sk_buff *skb, enum ip_conntrack_info *ctinfo)
182 *ctinfo = skb->nfctinfo;
183 return (struct nf_conn *)skb->nfct;
186 /* decrement reference count on a conntrack */
187 static inline void nf_ct_put(struct nf_conn *ct)
190 nf_conntrack_put(&ct->ct_general);
193 /* call to create an explicit dependency on nf_conntrack. */
194 extern void need_nf_conntrack(void);
196 extern int nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse,
197 const struct nf_conntrack_tuple *orig);
199 extern void __nf_ct_refresh_acct(struct nf_conn *ct,
200 enum ip_conntrack_info ctinfo,
201 const struct sk_buff *skb,
202 unsigned long extra_jiffies,
205 /* Refresh conntrack for this many jiffies and do accounting */
206 static inline void nf_ct_refresh_acct(struct nf_conn *ct,
207 enum ip_conntrack_info ctinfo,
208 const struct sk_buff *skb,
209 unsigned long extra_jiffies)
211 __nf_ct_refresh_acct(ct, ctinfo, skb, extra_jiffies, 1);
214 /* Refresh conntrack for this many jiffies */
215 static inline void nf_ct_refresh(struct nf_conn *ct,
216 const struct sk_buff *skb,
217 unsigned long extra_jiffies)
219 __nf_ct_refresh_acct(ct, 0, skb, extra_jiffies, 0);
222 /* These are for NAT. Icky. */
223 /* Update TCP window tracking data when NAT mangles the packet */
224 extern void nf_conntrack_tcp_update(struct sk_buff *skb,
225 unsigned int dataoff,
226 struct nf_conn *conntrack,
229 /* Call me when a conntrack is destroyed. */
230 extern void (*nf_conntrack_destroyed)(struct nf_conn *conntrack);
232 /* Fake conntrack entry for untracked connections */
233 extern struct nf_conn nf_conntrack_untracked;
235 extern int nf_ct_no_defrag;
237 /* Iterate over all conntracks: if iter returns true, it's deleted. */
239 nf_ct_iterate_cleanup(int (*iter)(struct nf_conn *i, void *data), void *data);
240 extern void nf_conntrack_free(struct nf_conn *ct);
241 extern struct nf_conn *
242 nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
243 const struct nf_conntrack_tuple *repl);
245 /* It's confirmed if it is, or has been in the hash table. */
246 static inline int nf_ct_is_confirmed(struct nf_conn *ct)
248 return test_bit(IPS_CONFIRMED_BIT, &ct->status);
251 static inline int nf_ct_is_dying(struct nf_conn *ct)
253 return test_bit(IPS_DYING_BIT, &ct->status);
256 extern unsigned int nf_conntrack_htable_size;
258 #define NF_CT_STAT_INC(count) (__get_cpu_var(nf_conntrack_stat).count++)
260 #ifdef CONFIG_NF_CONNTRACK_EVENTS
261 #include <linux/notifier.h>
262 #include <linux/interrupt.h>
264 struct nf_conntrack_ecache {
268 DECLARE_PER_CPU(struct nf_conntrack_ecache, nf_conntrack_ecache);
270 #define CONNTRACK_ECACHE(x) (__get_cpu_var(nf_conntrack_ecache).x)
272 extern struct notifier_block *nf_conntrack_chain;
273 extern struct notifier_block *nf_conntrack_expect_chain;
275 static inline int nf_conntrack_register_notifier(struct notifier_block *nb)
277 return notifier_chain_register(&nf_conntrack_chain, nb);
280 static inline int nf_conntrack_unregister_notifier(struct notifier_block *nb)
282 return notifier_chain_unregister(&nf_conntrack_chain, nb);
286 nf_conntrack_expect_register_notifier(struct notifier_block *nb)
288 return notifier_chain_register(&nf_conntrack_expect_chain, nb);
292 nf_conntrack_expect_unregister_notifier(struct notifier_block *nb)
294 return notifier_chain_unregister(&nf_conntrack_expect_chain, nb);
297 extern void nf_ct_deliver_cached_events(const struct nf_conn *ct);
298 extern void __nf_ct_event_cache_init(struct nf_conn *ct);
301 nf_conntrack_event_cache(enum ip_conntrack_events event,
302 const struct sk_buff *skb)
304 struct nf_conn *ct = (struct nf_conn *)skb->nfct;
305 struct nf_conntrack_ecache *ecache;
308 ecache = &__get_cpu_var(nf_conntrack_ecache);
309 if (ct != ecache->ct)
310 __nf_ct_event_cache_init(ct);
311 ecache->events |= event;
315 static inline void nf_conntrack_event(enum ip_conntrack_events event,
318 if (nf_ct_is_confirmed(ct) && !nf_ct_is_dying(ct))
319 notifier_call_chain(&nf_conntrack_chain, event, ct);
323 nf_conntrack_expect_event(enum ip_conntrack_expect_events event,
324 struct nf_conntrack_expect *exp)
326 notifier_call_chain(&nf_conntrack_expect_chain, event, exp);
328 #else /* CONFIG_NF_CONNTRACK_EVENTS */
329 static inline void nf_conntrack_event_cache(enum ip_conntrack_events event,
330 const struct sk_buff *skb) {}
331 static inline void nf_conntrack_event(enum ip_conntrack_events event,
332 struct nf_conn *ct) {}
333 static inline void nf_ct_deliver_cached_events(const struct nf_conn *ct) {}
335 nf_conntrack_expect_event(enum ip_conntrack_expect_events event,
336 struct nf_conntrack_expect *exp) {}
337 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
339 /* no helper, no nat */
340 #define NF_CT_F_BASIC 0
342 #define NF_CT_F_HELP 1
344 #define NF_CT_F_NAT 2
345 #define NF_CT_F_NUM 4
348 nf_conntrack_register_cache(u_int32_t features, const char *name, size_t size,
349 int (*init_conntrack)(struct nf_conn *, u_int32_t));
351 nf_conntrack_unregister_cache(u_int32_t features);
353 #endif /* __KERNEL__ */
354 #endif /* _NF_CONNTRACK_H */