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/bitops.h>
19 #include <linux/compiler.h>
20 #include <asm/atomic.h>
22 #include <linux/netfilter/nf_conntrack_tcp.h>
23 #include <linux/netfilter/nf_conntrack_sctp.h>
24 #include <linux/netfilter/nf_conntrack_proto_gre.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;
40 union nf_conntrack_expect_proto {
41 /* insert expect proto private data here */
44 /* Add protocol helper include file here */
45 #include <linux/netfilter/nf_conntrack_ftp.h>
46 #include <linux/netfilter/nf_conntrack_pptp.h>
47 #include <linux/netfilter/nf_conntrack_h323.h>
48 #include <linux/netfilter/nf_conntrack_sane.h>
50 /* per conntrack: application helper private data */
51 union nf_conntrack_help {
52 /* insert conntrack helper private data (master) here */
53 struct nf_ct_ftp_master ct_ftp_info;
54 struct nf_ct_pptp_master ct_pptp_info;
55 struct nf_ct_h323_master ct_h323_info;
56 struct nf_ct_sane_master ct_sane_info;
59 #include <linux/types.h>
60 #include <linux/skbuff.h>
61 #include <linux/timer.h>
63 #ifdef CONFIG_NETFILTER_DEBUG
64 #define NF_CT_ASSERT(x) \
67 /* Wooah! I'm tripping my conntrack in a frenzy of \
69 printk("NF_CT_ASSERT: %s:%i(%s)\n", \
70 __FILE__, __LINE__, __FUNCTION__); \
73 #define NF_CT_ASSERT(x)
76 struct nf_conntrack_helper;
78 /* nf_conn feature for connections that have a helper */
81 struct nf_conntrack_helper *helper;
83 union nf_conntrack_help help;
85 /* Current number of expected connections */
86 unsigned int expecting;
90 #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
91 #include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
95 /* Usage count in here is 1 for hash table/destruct timer, 1 per skb,
96 plus 1 for any connection(s) we are `master' for */
97 struct nf_conntrack ct_general;
99 /* XXX should I move this to the tail ? - Y.K */
100 /* These are my tuples; original and reply */
101 struct nf_conntrack_tuple_hash tuplehash[IP_CT_DIR_MAX];
103 /* Have we seen traffic both ways yet? (bitset) */
104 unsigned long status;
106 /* If we were expected by an expectation, this will be it */
107 struct nf_conn *master;
109 /* Timer function; drops refcnt when it goes off. */
110 struct timer_list timeout;
112 #ifdef CONFIG_NF_CT_ACCT
113 /* Accounting Information (same cache line as other written members) */
114 struct ip_conntrack_counter counters[IP_CT_DIR_MAX];
117 /* Unique ID that identifies this conntrack*/
120 /* features - nat, helper, ... used by allocating system */
123 #if defined(CONFIG_NF_CONNTRACK_MARK)
127 #ifdef CONFIG_NF_CONNTRACK_SECMARK
131 /* Storage reserved for other modules: */
132 union nf_conntrack_proto proto;
135 struct nf_ct_ext *ext;
137 /* features dynamically at the end: helper, nat (both optional) */
141 static inline struct nf_conn *
142 nf_ct_tuplehash_to_ctrack(const struct nf_conntrack_tuple_hash *hash)
144 return container_of(hash, struct nf_conn,
145 tuplehash[hash->tuple.dst.dir]);
148 /* get master conntrack via master expectation */
149 #define master_ct(conntr) (conntr->master)
151 /* Alter reply tuple (maybe alter helper). */
153 nf_conntrack_alter_reply(struct nf_conn *conntrack,
154 const struct nf_conntrack_tuple *newreply);
156 /* Is this tuple taken? (ignoring any belonging to the given
159 nf_conntrack_tuple_taken(const struct nf_conntrack_tuple *tuple,
160 const struct nf_conn *ignored_conntrack);
162 /* Return conntrack_info and tuple hash for given skb. */
163 static inline struct nf_conn *
164 nf_ct_get(const struct sk_buff *skb, enum ip_conntrack_info *ctinfo)
166 *ctinfo = skb->nfctinfo;
167 return (struct nf_conn *)skb->nfct;
170 /* decrement reference count on a conntrack */
171 static inline void nf_ct_put(struct nf_conn *ct)
174 nf_conntrack_put(&ct->ct_general);
177 /* Protocol module loading */
178 extern int nf_ct_l3proto_try_module_get(unsigned short l3proto);
179 extern void nf_ct_l3proto_module_put(unsigned short l3proto);
181 extern struct nf_conntrack_tuple_hash *
182 __nf_conntrack_find(const struct nf_conntrack_tuple *tuple,
183 const struct nf_conn *ignored_conntrack);
185 extern void nf_conntrack_hash_insert(struct nf_conn *ct);
187 extern void nf_conntrack_flush(void);
189 extern int nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse,
190 const struct nf_conntrack_tuple *orig);
192 extern void __nf_ct_refresh_acct(struct nf_conn *ct,
193 enum ip_conntrack_info ctinfo,
194 const struct sk_buff *skb,
195 unsigned long extra_jiffies,
198 /* Refresh conntrack for this many jiffies and do accounting */
199 static inline 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)
204 __nf_ct_refresh_acct(ct, ctinfo, skb, extra_jiffies, 1);
207 /* Refresh conntrack for this many jiffies */
208 static inline void nf_ct_refresh(struct nf_conn *ct,
209 const struct sk_buff *skb,
210 unsigned long extra_jiffies)
212 __nf_ct_refresh_acct(ct, 0, skb, extra_jiffies, 0);
215 /* These are for NAT. Icky. */
216 /* Update TCP window tracking data when NAT mangles the packet */
217 extern void nf_conntrack_tcp_update(struct sk_buff *skb,
218 unsigned int dataoff,
219 struct nf_conn *conntrack,
222 /* Call me when a conntrack is destroyed. */
223 extern void (*nf_conntrack_destroyed)(struct nf_conn *conntrack);
225 /* Fake conntrack entry for untracked connections */
226 extern struct nf_conn nf_conntrack_untracked;
228 extern int nf_ct_no_defrag;
230 /* Iterate over all conntracks: if iter returns true, it's deleted. */
232 nf_ct_iterate_cleanup(int (*iter)(struct nf_conn *i, void *data), void *data);
233 extern void nf_conntrack_free(struct nf_conn *ct);
234 extern struct nf_conn *
235 nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
236 const struct nf_conntrack_tuple *repl);
238 /* It's confirmed if it is, or has been in the hash table. */
239 static inline int nf_ct_is_confirmed(struct nf_conn *ct)
241 return test_bit(IPS_CONFIRMED_BIT, &ct->status);
244 static inline int nf_ct_is_dying(struct nf_conn *ct)
246 return test_bit(IPS_DYING_BIT, &ct->status);
249 static inline int nf_ct_is_untracked(const struct sk_buff *skb)
251 return (skb->nfct == &nf_conntrack_untracked.ct_general);
254 extern unsigned int nf_conntrack_htable_size;
255 extern int nf_conntrack_checksum;
256 extern atomic_t nf_conntrack_count;
257 extern int nf_conntrack_max;
259 DECLARE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
260 #define NF_CT_STAT_INC(count) (__get_cpu_var(nf_conntrack_stat).count++)
261 #define NF_CT_STAT_INC_ATOMIC(count) \
263 local_bh_disable(); \
264 __get_cpu_var(nf_conntrack_stat).count++; \
268 /* no helper, no nat */
269 #define NF_CT_F_BASIC 0
271 #define NF_CT_F_HELP 1
273 #define NF_CT_F_NAT 2
274 #define NF_CT_F_NUM 4
277 nf_conntrack_register_cache(u_int32_t features, const char *name, size_t size);
279 nf_conntrack_unregister_cache(u_int32_t features);
281 /* valid combinations:
282 * basic: nf_conn, nf_conn .. nf_conn_help
283 * nat: nf_conn .. nf_conn_nat, nf_conn .. nf_conn_nat .. nf_conn help
285 #ifdef CONFIG_NF_NAT_NEEDED
286 #include <net/netfilter/nf_nat.h>
287 static inline struct nf_conn_nat *nfct_nat(const struct nf_conn *ct)
289 unsigned int offset = sizeof(struct nf_conn);
291 if (!(ct->features & NF_CT_F_NAT))
294 offset = ALIGN(offset, __alignof__(struct nf_conn_nat));
295 return (struct nf_conn_nat *) ((void *)ct + offset);
298 static inline struct nf_conn_help *nfct_help(const struct nf_conn *ct)
300 unsigned int offset = sizeof(struct nf_conn);
302 if (!(ct->features & NF_CT_F_HELP))
304 if (ct->features & NF_CT_F_NAT) {
305 offset = ALIGN(offset, __alignof__(struct nf_conn_nat));
306 offset += sizeof(struct nf_conn_nat);
309 offset = ALIGN(offset, __alignof__(struct nf_conn_help));
310 return (struct nf_conn_help *) ((void *)ct + offset);
313 static inline struct nf_conn_help *nfct_help(const struct nf_conn *ct)
315 unsigned int offset = sizeof(struct nf_conn);
317 if (!(ct->features & NF_CT_F_HELP))
320 offset = ALIGN(offset, __alignof__(struct nf_conn_help));
321 return (struct nf_conn_help *) ((void *)ct + offset);
323 #endif /* CONFIG_NF_NAT_NEEDED */
324 #endif /* __KERNEL__ */
325 #endif /* _NF_CONNTRACK_H */