1 #ifndef __LINUX_NETFILTER_H
2 #define __LINUX_NETFILTER_H
4 #include <linux/init.h>
5 #include <linux/skbuff.h>
10 #include <linux/wait.h>
11 #include <linux/list.h>
12 #include <linux/static_key.h>
13 #include <uapi/linux/netfilter.h>
14 #ifdef CONFIG_NETFILTER
15 static inline int NF_DROP_GETERR(int verdict
)
17 return -(verdict
>> NF_VERDICT_QBITS
);
20 static inline int nf_inet_addr_cmp(const union nf_inet_addr
*a1
,
21 const union nf_inet_addr
*a2
)
23 return a1
->all
[0] == a2
->all
[0] &&
24 a1
->all
[1] == a2
->all
[1] &&
25 a1
->all
[2] == a2
->all
[2] &&
26 a1
->all
[3] == a2
->all
[3];
29 static inline void nf_inet_addr_mask(const union nf_inet_addr
*a1
,
30 union nf_inet_addr
*result
,
31 const union nf_inet_addr
*mask
)
33 result
->all
[0] = a1
->all
[0] & mask
->all
[0];
34 result
->all
[1] = a1
->all
[1] & mask
->all
[1];
35 result
->all
[2] = a1
->all
[2] & mask
->all
[2];
36 result
->all
[3] = a1
->all
[3] & mask
->all
[3];
39 int netfilter_init(void);
41 /* Largest hook number + 1 */
42 #define NF_MAX_HOOKS 8
50 struct nf_hook_state
{
54 struct net_device
*in
;
55 struct net_device
*out
;
57 int (*okfn
)(struct sock
*, struct sk_buff
*);
60 static inline void nf_hook_state_init(struct nf_hook_state
*p
,
62 int thresh
, u_int8_t pf
,
63 struct net_device
*indev
,
64 struct net_device
*outdev
,
66 int (*okfn
)(struct sock
*, struct sk_buff
*))
77 typedef unsigned int nf_hookfn(const struct nf_hook_ops
*ops
,
79 const struct nf_hook_state
*state
);
82 struct list_head list
;
84 /* User fills in from here down. */
90 /* Hooks are ordered in ascending priority. */
94 struct nf_sockopt_ops
{
95 struct list_head list
;
99 /* Non-inclusive ranges: use 0/0/NULL to never get called. */
102 int (*set
)(struct sock
*sk
, int optval
, void __user
*user
, unsigned int len
);
104 int (*compat_set
)(struct sock
*sk
, int optval
,
105 void __user
*user
, unsigned int len
);
109 int (*get
)(struct sock
*sk
, int optval
, void __user
*user
, int *len
);
111 int (*compat_get
)(struct sock
*sk
, int optval
,
112 void __user
*user
, int *len
);
114 /* Use the module struct to lock set/get code in place */
115 struct module
*owner
;
118 /* Function to register/unregister hook points. */
119 int nf_register_hook(struct nf_hook_ops
*reg
);
120 void nf_unregister_hook(struct nf_hook_ops
*reg
);
121 int nf_register_hooks(struct nf_hook_ops
*reg
, unsigned int n
);
122 void nf_unregister_hooks(struct nf_hook_ops
*reg
, unsigned int n
);
124 /* Functions to register get/setsockopt ranges (non-inclusive). You
125 need to check permissions yourself! */
126 int nf_register_sockopt(struct nf_sockopt_ops
*reg
);
127 void nf_unregister_sockopt(struct nf_sockopt_ops
*reg
);
129 extern struct list_head nf_hooks
[NFPROTO_NUMPROTO
][NF_MAX_HOOKS
];
131 #ifdef HAVE_JUMP_LABEL
132 extern struct static_key nf_hooks_needed
[NFPROTO_NUMPROTO
][NF_MAX_HOOKS
];
134 static inline bool nf_hooks_active(u_int8_t pf
, unsigned int hook
)
136 if (__builtin_constant_p(pf
) &&
137 __builtin_constant_p(hook
))
138 return static_key_false(&nf_hooks_needed
[pf
][hook
]);
140 return !list_empty(&nf_hooks
[pf
][hook
]);
143 static inline bool nf_hooks_active(u_int8_t pf
, unsigned int hook
)
145 return !list_empty(&nf_hooks
[pf
][hook
]);
149 int nf_hook_slow(struct sk_buff
*skb
, struct nf_hook_state
*state
);
152 * nf_hook_thresh - call a netfilter hook
154 * Returns 1 if the hook has allowed the packet to pass. The function
155 * okfn must be invoked by the caller in this case. Any other return
156 * value indicates the packet has been consumed by the hook.
158 static inline int nf_hook_thresh(u_int8_t pf
, unsigned int hook
,
161 struct net_device
*indev
,
162 struct net_device
*outdev
,
163 int (*okfn
)(struct sock
*, struct sk_buff
*),
166 if (nf_hooks_active(pf
, hook
)) {
167 struct nf_hook_state state
;
169 nf_hook_state_init(&state
, hook
, thresh
, pf
,
170 indev
, outdev
, sk
, okfn
);
171 return nf_hook_slow(skb
, &state
);
176 static inline int nf_hook(u_int8_t pf
, unsigned int hook
, struct sock
*sk
,
177 struct sk_buff
*skb
, struct net_device
*indev
,
178 struct net_device
*outdev
,
179 int (*okfn
)(struct sock
*, struct sk_buff
*))
181 return nf_hook_thresh(pf
, hook
, sk
, skb
, indev
, outdev
, okfn
, INT_MIN
);
184 /* Activate hook; either okfn or kfree_skb called, unless a hook
185 returns NF_STOLEN (in which case, it's up to the hook to deal with
188 Returns -ERRNO if packet dropped. Zero means queued, stolen or
193 > I don't want nf_hook to return anything because people might forget
194 > about async and trust the return value to mean "packet was ok".
197 Just document it clearly, then you can expect some sense from kernel
202 NF_HOOK_THRESH(uint8_t pf
, unsigned int hook
, struct sock
*sk
,
203 struct sk_buff
*skb
, struct net_device
*in
,
204 struct net_device
*out
,
205 int (*okfn
)(struct sock
*, struct sk_buff
*), int thresh
)
207 int ret
= nf_hook_thresh(pf
, hook
, sk
, skb
, in
, out
, okfn
, thresh
);
214 NF_HOOK_COND(uint8_t pf
, unsigned int hook
, struct sock
*sk
,
215 struct sk_buff
*skb
, struct net_device
*in
, struct net_device
*out
,
216 int (*okfn
)(struct sock
*, struct sk_buff
*), bool cond
)
221 ((ret
= nf_hook_thresh(pf
, hook
, sk
, skb
, in
, out
, okfn
, INT_MIN
)) == 1))
227 NF_HOOK(uint8_t pf
, unsigned int hook
, struct sock
*sk
, struct sk_buff
*skb
,
228 struct net_device
*in
, struct net_device
*out
,
229 int (*okfn
)(struct sock
*, struct sk_buff
*))
231 return NF_HOOK_THRESH(pf
, hook
, sk
, skb
, in
, out
, okfn
, INT_MIN
);
234 /* Call setsockopt() */
235 int nf_setsockopt(struct sock
*sk
, u_int8_t pf
, int optval
, char __user
*opt
,
237 int nf_getsockopt(struct sock
*sk
, u_int8_t pf
, int optval
, char __user
*opt
,
240 int compat_nf_setsockopt(struct sock
*sk
, u_int8_t pf
, int optval
,
241 char __user
*opt
, unsigned int len
);
242 int compat_nf_getsockopt(struct sock
*sk
, u_int8_t pf
, int optval
,
243 char __user
*opt
, int *len
);
246 /* Call this before modifying an existing packet: ensures it is
247 modifiable and linear to the point you care about (writable_len).
248 Returns true or false. */
249 int skb_make_writable(struct sk_buff
*skb
, unsigned int writable_len
);
252 struct nf_queue_entry
;
255 unsigned short family
;
256 __sum16 (*checksum
)(struct sk_buff
*skb
, unsigned int hook
,
257 unsigned int dataoff
, u_int8_t protocol
);
258 __sum16 (*checksum_partial
)(struct sk_buff
*skb
,
260 unsigned int dataoff
,
263 int (*route
)(struct net
*net
, struct dst_entry
**dst
,
264 struct flowi
*fl
, bool strict
);
265 void (*saveroute
)(const struct sk_buff
*skb
,
266 struct nf_queue_entry
*entry
);
267 int (*reroute
)(struct sk_buff
*skb
,
268 const struct nf_queue_entry
*entry
);
272 extern const struct nf_afinfo __rcu
*nf_afinfo
[NFPROTO_NUMPROTO
];
273 static inline const struct nf_afinfo
*nf_get_afinfo(unsigned short family
)
275 return rcu_dereference(nf_afinfo
[family
]);
278 static inline __sum16
279 nf_checksum(struct sk_buff
*skb
, unsigned int hook
, unsigned int dataoff
,
280 u_int8_t protocol
, unsigned short family
)
282 const struct nf_afinfo
*afinfo
;
286 afinfo
= nf_get_afinfo(family
);
288 csum
= afinfo
->checksum(skb
, hook
, dataoff
, protocol
);
293 static inline __sum16
294 nf_checksum_partial(struct sk_buff
*skb
, unsigned int hook
,
295 unsigned int dataoff
, unsigned int len
,
296 u_int8_t protocol
, unsigned short family
)
298 const struct nf_afinfo
*afinfo
;
302 afinfo
= nf_get_afinfo(family
);
304 csum
= afinfo
->checksum_partial(skb
, hook
, dataoff
, len
,
310 int nf_register_afinfo(const struct nf_afinfo
*afinfo
);
311 void nf_unregister_afinfo(const struct nf_afinfo
*afinfo
);
313 #include <net/flow.h>
314 extern void (*nf_nat_decode_session_hook
)(struct sk_buff
*, struct flowi
*);
317 nf_nat_decode_session(struct sk_buff
*skb
, struct flowi
*fl
, u_int8_t family
)
319 #ifdef CONFIG_NF_NAT_NEEDED
320 void (*decodefn
)(struct sk_buff
*, struct flowi
*);
323 decodefn
= rcu_dereference(nf_nat_decode_session_hook
);
330 #else /* !CONFIG_NETFILTER */
331 #define NF_HOOK(pf, hook, sk, skb, indev, outdev, okfn) (okfn)(sk, skb)
332 #define NF_HOOK_COND(pf, hook, sk, skb, indev, outdev, okfn, cond) (okfn)(sk, skb)
333 static inline int nf_hook_thresh(u_int8_t pf
, unsigned int hook
,
336 struct net_device
*indev
,
337 struct net_device
*outdev
,
338 int (*okfn
)(struct sock
*sk
, struct sk_buff
*), int thresh
)
340 return okfn(sk
, skb
);
342 static inline int nf_hook(u_int8_t pf
, unsigned int hook
, struct sock
*sk
,
343 struct sk_buff
*skb
, struct net_device
*indev
,
344 struct net_device
*outdev
,
345 int (*okfn
)(struct sock
*, struct sk_buff
*))
351 nf_nat_decode_session(struct sk_buff
*skb
, struct flowi
*fl
, u_int8_t family
)
354 #endif /*CONFIG_NETFILTER*/
356 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
357 extern void (*ip_ct_attach
)(struct sk_buff
*, const struct sk_buff
*) __rcu
;
358 void nf_ct_attach(struct sk_buff
*, const struct sk_buff
*);
359 extern void (*nf_ct_destroy
)(struct nf_conntrack
*) __rcu
;
362 enum ip_conntrack_info
;
366 size_t (*build_size
)(const struct nf_conn
*ct
);
367 int (*build
)(struct sk_buff
*skb
, struct nf_conn
*ct
);
368 int (*parse
)(const struct nlattr
*attr
, struct nf_conn
*ct
);
369 int (*attach_expect
)(const struct nlattr
*attr
, struct nf_conn
*ct
,
370 u32 portid
, u32 report
);
371 void (*seq_adjust
)(struct sk_buff
*skb
, struct nf_conn
*ct
,
372 enum ip_conntrack_info ctinfo
, s32 off
);
374 extern struct nfq_ct_hook __rcu
*nfq_ct_hook
;
376 static inline void nf_ct_attach(struct sk_buff
*new, struct sk_buff
*skb
) {}
379 #endif /*__LINUX_NETFILTER_H*/