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 <net/netfilter/ipv4/nf_conntrack_icmp.h>
25 #include <net/netfilter/ipv6/nf_conntrack_icmpv6.h>
27 #include <net/netfilter/nf_conntrack_tuple.h>
29 /* per conntrack: protocol private data */
30 union nf_conntrack_proto {
31 /* insert conntrack proto private data here */
32 struct ip_ct_sctp sctp;
34 struct ip_ct_icmp icmp;
35 struct nf_ct_icmpv6 icmpv6;
38 union nf_conntrack_expect_proto {
39 /* insert expect proto private data here */
42 /* Add protocol helper include file here */
43 #include <linux/netfilter/nf_conntrack_ftp.h>
45 /* per conntrack: application helper private data */
46 union nf_conntrack_help {
47 /* insert conntrack helper private data (master) here */
48 struct nf_ct_ftp_master ct_ftp_info;
51 #include <linux/types.h>
52 #include <linux/skbuff.h>
54 #ifdef CONFIG_NETFILTER_DEBUG
55 #define NF_CT_ASSERT(x) \
58 /* Wooah! I'm tripping my conntrack in a frenzy of \
60 printk("NF_CT_ASSERT: %s:%i(%s)\n", \
61 __FILE__, __LINE__, __FUNCTION__); \
64 #define NF_CT_ASSERT(x)
67 struct nf_conntrack_helper;
69 /* nf_conn feature for connections that have a helper */
72 struct nf_conntrack_helper *helper;
74 union nf_conntrack_help help;
76 /* Current number of expected connections */
77 unsigned int expecting;
81 #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
82 #include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
86 /* Usage count in here is 1 for hash table/destruct timer, 1 per skb,
87 plus 1 for any connection(s) we are `master' for */
88 struct nf_conntrack ct_general;
90 /* XXX should I move this to the tail ? - Y.K */
91 /* These are my tuples; original and reply */
92 struct nf_conntrack_tuple_hash tuplehash[IP_CT_DIR_MAX];
94 /* Have we seen traffic both ways yet? (bitset) */
97 /* If we were expected by an expectation, this will be it */
98 struct nf_conn *master;
100 /* Timer function; drops refcnt when it goes off. */
101 struct timer_list timeout;
103 #ifdef CONFIG_NF_CT_ACCT
104 /* Accounting Information (same cache line as other written members) */
105 struct ip_conntrack_counter counters[IP_CT_DIR_MAX];
108 /* Unique ID that identifies this conntrack*/
111 /* features - nat, helper, ... used by allocating system */
114 #if defined(CONFIG_NF_CONNTRACK_MARK)
118 #ifdef CONFIG_NF_CONNTRACK_SECMARK
122 /* Storage reserved for other modules: */
123 union nf_conntrack_proto proto;
125 /* features dynamically at the end: helper, nat (both optional) */
129 static inline struct nf_conn *
130 nf_ct_tuplehash_to_ctrack(const struct nf_conntrack_tuple_hash *hash)
132 return container_of(hash, struct nf_conn,
133 tuplehash[hash->tuple.dst.dir]);
136 /* get master conntrack via master expectation */
137 #define master_ct(conntr) (conntr->master)
139 /* Alter reply tuple (maybe alter helper). */
141 nf_conntrack_alter_reply(struct nf_conn *conntrack,
142 const struct nf_conntrack_tuple *newreply);
144 /* Is this tuple taken? (ignoring any belonging to the given
147 nf_conntrack_tuple_taken(const struct nf_conntrack_tuple *tuple,
148 const struct nf_conn *ignored_conntrack);
150 /* Return conntrack_info and tuple hash for given skb. */
151 static inline struct nf_conn *
152 nf_ct_get(const struct sk_buff *skb, enum ip_conntrack_info *ctinfo)
154 *ctinfo = skb->nfctinfo;
155 return (struct nf_conn *)skb->nfct;
158 /* decrement reference count on a conntrack */
159 static inline void nf_ct_put(struct nf_conn *ct)
162 nf_conntrack_put(&ct->ct_general);
165 /* Protocol module loading */
166 extern int nf_ct_l3proto_try_module_get(unsigned short l3proto);
167 extern void nf_ct_l3proto_module_put(unsigned short l3proto);
169 extern struct nf_conntrack_tuple_hash *
170 __nf_conntrack_find(const struct nf_conntrack_tuple *tuple,
171 const struct nf_conn *ignored_conntrack);
173 extern void nf_conntrack_hash_insert(struct nf_conn *ct);
175 extern void nf_conntrack_flush(void);
177 extern struct nf_conntrack_helper *
178 nf_ct_helper_find_get( const struct nf_conntrack_tuple *tuple);
179 extern void nf_ct_helper_put(struct nf_conntrack_helper *helper);
181 extern struct nf_conntrack_helper *
182 __nf_conntrack_helper_find_byname(const char *name);
184 extern int nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse,
185 const struct nf_conntrack_tuple *orig);
187 extern void __nf_ct_refresh_acct(struct nf_conn *ct,
188 enum ip_conntrack_info ctinfo,
189 const struct sk_buff *skb,
190 unsigned long extra_jiffies,
193 /* Refresh conntrack for this many jiffies and do accounting */
194 static inline void nf_ct_refresh_acct(struct nf_conn *ct,
195 enum ip_conntrack_info ctinfo,
196 const struct sk_buff *skb,
197 unsigned long extra_jiffies)
199 __nf_ct_refresh_acct(ct, ctinfo, skb, extra_jiffies, 1);
202 /* Refresh conntrack for this many jiffies */
203 static inline void nf_ct_refresh(struct nf_conn *ct,
204 const struct sk_buff *skb,
205 unsigned long extra_jiffies)
207 __nf_ct_refresh_acct(ct, 0, skb, extra_jiffies, 0);
210 /* These are for NAT. Icky. */
211 /* Update TCP window tracking data when NAT mangles the packet */
212 extern void nf_conntrack_tcp_update(struct sk_buff *skb,
213 unsigned int dataoff,
214 struct nf_conn *conntrack,
217 /* Call me when a conntrack is destroyed. */
218 extern void (*nf_conntrack_destroyed)(struct nf_conn *conntrack);
220 /* Fake conntrack entry for untracked connections */
221 extern struct nf_conn nf_conntrack_untracked;
223 extern int nf_ct_no_defrag;
225 /* Iterate over all conntracks: if iter returns true, it's deleted. */
227 nf_ct_iterate_cleanup(int (*iter)(struct nf_conn *i, void *data), void *data);
228 extern void nf_conntrack_free(struct nf_conn *ct);
229 extern struct nf_conn *
230 nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
231 const struct nf_conntrack_tuple *repl);
233 /* It's confirmed if it is, or has been in the hash table. */
234 static inline int nf_ct_is_confirmed(struct nf_conn *ct)
236 return test_bit(IPS_CONFIRMED_BIT, &ct->status);
239 static inline int nf_ct_is_dying(struct nf_conn *ct)
241 return test_bit(IPS_DYING_BIT, &ct->status);
244 extern unsigned int nf_conntrack_htable_size;
245 extern int nf_conntrack_checksum;
246 extern atomic_t nf_conntrack_count;
247 extern int nf_conntrack_max;
249 DECLARE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
250 #define NF_CT_STAT_INC(count) (__get_cpu_var(nf_conntrack_stat).count++)
252 /* no helper, no nat */
253 #define NF_CT_F_BASIC 0
255 #define NF_CT_F_HELP 1
257 #define NF_CT_F_NAT 2
258 #define NF_CT_F_NUM 4
261 nf_conntrack_register_cache(u_int32_t features, const char *name, size_t size);
263 nf_conntrack_unregister_cache(u_int32_t features);
265 /* valid combinations:
266 * basic: nf_conn, nf_conn .. nf_conn_help
267 * nat: nf_conn .. nf_conn_nat, nf_conn .. nf_conn_nat .. nf_conn help
269 #ifdef CONFIG_NF_NAT_NEEDED
270 static inline struct nf_conn_nat *nfct_nat(const struct nf_conn *ct)
272 unsigned int offset = sizeof(struct nf_conn);
274 if (!(ct->features & NF_CT_F_NAT))
277 offset = ALIGN(offset, __alignof__(struct nf_conn_nat));
278 return (struct nf_conn_nat *) ((void *)ct + offset);
281 static inline struct nf_conn_help *nfct_help(const struct nf_conn *ct)
283 unsigned int offset = sizeof(struct nf_conn);
285 if (!(ct->features & NF_CT_F_HELP))
287 if (ct->features & NF_CT_F_NAT) {
288 offset = ALIGN(offset, __alignof__(struct nf_conn_nat));
289 offset += sizeof(struct nf_conn_nat);
292 offset = ALIGN(offset, __alignof__(struct nf_conn_help));
293 return (struct nf_conn_help *) ((void *)ct + offset);
296 static inline struct nf_conn_help *nfct_help(const struct nf_conn *ct)
298 unsigned int offset = sizeof(struct nf_conn);
300 if (!(ct->features & NF_CT_F_HELP))
303 offset = ALIGN(offset, __alignof__(struct nf_conn_help));
304 return (struct nf_conn_help *) ((void *)ct + offset);
306 #endif /* CONFIG_NF_NAT_NEEDED */
307 #endif /* __KERNEL__ */
308 #endif /* _NF_CONNTRACK_H */