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>
17 #include <linux/bitops.h>
18 #include <linux/compiler.h>
19 #include <linux/atomic.h>
21 #include <linux/netfilter/nf_conntrack_tcp.h>
22 #include <linux/netfilter/nf_conntrack_dccp.h>
23 #include <linux/netfilter/nf_conntrack_sctp.h>
24 #include <linux/netfilter/nf_conntrack_proto_gre.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 nf_ct_dccp dccp
;
33 struct ip_ct_sctp sctp
;
38 union nf_conntrack_expect_proto
{
39 /* insert expect proto private data here */
42 #include <linux/types.h>
43 #include <linux/skbuff.h>
44 #include <linux/timer.h>
46 #ifdef CONFIG_NETFILTER_DEBUG
47 #define NF_CT_ASSERT(x) WARN_ON(!(x))
49 #define NF_CT_ASSERT(x)
52 struct nf_conntrack_helper
;
54 /* Must be kept in sync with the classes defined by helpers */
55 #define NF_CT_MAX_EXPECT_CLASSES 4
57 /* nf_conn feature for connections that have a helper */
60 struct nf_conntrack_helper __rcu
*helper
;
62 struct hlist_head expectations
;
64 /* Current number of expected connections */
65 u8 expecting
[NF_CT_MAX_EXPECT_CLASSES
];
67 /* private helper information. */
71 #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
72 #include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
75 /* Usage count in here is 1 for hash table/destruct timer, 1 per skb,
76 * plus 1 for any connection(s) we are `master' for
78 * Hint, SKB address this struct and refcnt via skb->nfct and
79 * helpers nf_conntrack_get() and nf_conntrack_put().
80 * Helper nf_ct_put() equals nf_conntrack_put() by dec refcnt,
81 * beware nf_ct_get() is different and don't inc refcnt.
83 struct nf_conntrack ct_general
;
88 #ifdef CONFIG_NF_CONNTRACK_ZONES
89 struct nf_conntrack_zone zone
;
91 /* XXX should I move this to the tail ? - Y.K */
92 /* These are my tuples; original and reply */
93 struct nf_conntrack_tuple_hash tuplehash
[IP_CT_DIR_MAX
];
95 /* Have we seen traffic both ways yet? (bitset) */
98 /* Timer function; drops refcnt when it goes off. */
99 struct timer_list timeout
;
101 possible_net_t ct_net
;
103 /* all members below initialized via memset */
104 u8 __nfct_init_offset
[0];
106 /* If we were expected by an expectation, this will be it */
107 struct nf_conn
*master
;
109 #if defined(CONFIG_NF_CONNTRACK_MARK)
113 #ifdef CONFIG_NF_CONNTRACK_SECMARK
118 struct nf_ct_ext
*ext
;
120 /* Storage reserved for other modules, must be the last member */
121 union nf_conntrack_proto proto
;
124 static inline struct nf_conn
*
125 nf_ct_tuplehash_to_ctrack(const struct nf_conntrack_tuple_hash
*hash
)
127 return container_of(hash
, struct nf_conn
,
128 tuplehash
[hash
->tuple
.dst
.dir
]);
131 static inline u_int16_t
nf_ct_l3num(const struct nf_conn
*ct
)
133 return ct
->tuplehash
[IP_CT_DIR_ORIGINAL
].tuple
.src
.l3num
;
136 static inline u_int8_t
nf_ct_protonum(const struct nf_conn
*ct
)
138 return ct
->tuplehash
[IP_CT_DIR_ORIGINAL
].tuple
.dst
.protonum
;
141 #define nf_ct_tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
143 /* get master conntrack via master expectation */
144 #define master_ct(conntr) (conntr->master)
146 extern struct net init_net
;
148 static inline struct net
*nf_ct_net(const struct nf_conn
*ct
)
150 return read_pnet(&ct
->ct_net
);
153 /* Alter reply tuple (maybe alter helper). */
154 void nf_conntrack_alter_reply(struct nf_conn
*ct
,
155 const struct nf_conntrack_tuple
*newreply
);
157 /* Is this tuple taken? (ignoring any belonging to the given
159 int 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 int nf_ct_l3proto_try_module_get(unsigned short l3proto
);
179 void nf_ct_l3proto_module_put(unsigned short l3proto
);
182 * Allocate a hashtable of hlist_head (if nulls == 0),
183 * or hlist_nulls_head (if nulls == 1)
185 void *nf_ct_alloc_hashtable(unsigned int *sizep
, int nulls
);
187 void nf_ct_free_hashtable(void *hash
, unsigned int size
);
189 int nf_conntrack_hash_check_insert(struct nf_conn
*ct
);
190 bool nf_ct_delete(struct nf_conn
*ct
, u32 pid
, int report
);
192 bool nf_ct_get_tuplepr(const struct sk_buff
*skb
, unsigned int nhoff
,
193 u_int16_t l3num
, struct net
*net
,
194 struct nf_conntrack_tuple
*tuple
);
195 bool nf_ct_invert_tuplepr(struct nf_conntrack_tuple
*inverse
,
196 const struct nf_conntrack_tuple
*orig
);
198 void __nf_ct_refresh_acct(struct nf_conn
*ct
, enum ip_conntrack_info ctinfo
,
199 const struct sk_buff
*skb
,
200 unsigned long extra_jiffies
, int do_acct
);
202 /* Refresh conntrack for this many jiffies and do accounting */
203 static inline void nf_ct_refresh_acct(struct nf_conn
*ct
,
204 enum ip_conntrack_info ctinfo
,
205 const struct sk_buff
*skb
,
206 unsigned long extra_jiffies
)
208 __nf_ct_refresh_acct(ct
, ctinfo
, skb
, extra_jiffies
, 1);
211 /* Refresh conntrack for this many jiffies */
212 static inline void nf_ct_refresh(struct nf_conn
*ct
,
213 const struct sk_buff
*skb
,
214 unsigned long extra_jiffies
)
216 __nf_ct_refresh_acct(ct
, 0, skb
, extra_jiffies
, 0);
219 bool __nf_ct_kill_acct(struct nf_conn
*ct
, enum ip_conntrack_info ctinfo
,
220 const struct sk_buff
*skb
, int do_acct
);
222 /* kill conntrack and do accounting */
223 static inline bool nf_ct_kill_acct(struct nf_conn
*ct
,
224 enum ip_conntrack_info ctinfo
,
225 const struct sk_buff
*skb
)
227 return __nf_ct_kill_acct(ct
, ctinfo
, skb
, 1);
230 /* kill conntrack without accounting */
231 static inline bool nf_ct_kill(struct nf_conn
*ct
)
233 return __nf_ct_kill_acct(ct
, 0, NULL
, 0);
236 /* These are for NAT. Icky. */
237 extern s32 (*nf_ct_nat_offset
)(const struct nf_conn
*ct
,
238 enum ip_conntrack_dir dir
,
241 /* Fake conntrack entry for untracked connections */
242 DECLARE_PER_CPU(struct nf_conn
, nf_conntrack_untracked
);
243 static inline struct nf_conn
*nf_ct_untracked_get(void)
245 return raw_cpu_ptr(&nf_conntrack_untracked
);
247 void nf_ct_untracked_status_or(unsigned long bits
);
249 /* Iterate over all conntracks: if iter returns true, it's deleted. */
250 void nf_ct_iterate_cleanup(struct net
*net
,
251 int (*iter
)(struct nf_conn
*i
, void *data
),
252 void *data
, u32 portid
, int report
);
254 struct nf_conntrack_zone
;
256 void nf_conntrack_free(struct nf_conn
*ct
);
257 struct nf_conn
*nf_conntrack_alloc(struct net
*net
,
258 const struct nf_conntrack_zone
*zone
,
259 const struct nf_conntrack_tuple
*orig
,
260 const struct nf_conntrack_tuple
*repl
,
263 static inline int nf_ct_is_template(const struct nf_conn
*ct
)
265 return test_bit(IPS_TEMPLATE_BIT
, &ct
->status
);
268 /* It's confirmed if it is, or has been in the hash table. */
269 static inline int nf_ct_is_confirmed(struct nf_conn
*ct
)
271 return test_bit(IPS_CONFIRMED_BIT
, &ct
->status
);
274 static inline int nf_ct_is_dying(struct nf_conn
*ct
)
276 return test_bit(IPS_DYING_BIT
, &ct
->status
);
279 static inline int nf_ct_is_untracked(const struct nf_conn
*ct
)
281 return test_bit(IPS_UNTRACKED_BIT
, &ct
->status
);
284 /* Packet is received from loopback */
285 static inline bool nf_is_loopback_packet(const struct sk_buff
*skb
)
287 return skb
->dev
&& skb
->skb_iif
&& skb
->dev
->flags
& IFF_LOOPBACK
;
292 int nf_conntrack_set_hashsize(const char *val
, struct kernel_param
*kp
);
293 int nf_conntrack_hash_resize(unsigned int hashsize
);
294 extern unsigned int nf_conntrack_htable_size
;
295 extern unsigned int nf_conntrack_max
;
297 struct nf_conn
*nf_ct_tmpl_alloc(struct net
*net
,
298 const struct nf_conntrack_zone
*zone
,
300 void nf_ct_tmpl_free(struct nf_conn
*tmpl
);
302 #define NF_CT_STAT_INC(net, count) __this_cpu_inc((net)->ct.stat->count)
303 #define NF_CT_STAT_INC_ATOMIC(net, count) this_cpu_inc((net)->ct.stat->count)
305 #define MODULE_ALIAS_NFCT_HELPER(helper) \
306 MODULE_ALIAS("nfct-helper-" helper)
308 #endif /* _NF_CONNTRACK_H */