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git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - include/linux/netfilter.h
1 #ifndef __LINUX_NETFILTER_H
2 #define __LINUX_NETFILTER_H
5 #include <linux/init.h>
6 #include <linux/types.h>
7 #include <linux/skbuff.h>
10 #include <linux/wait.h>
11 #include <linux/list.h>
13 #include <linux/compiler.h>
15 /* Responses from hook functions. */
22 #define NF_MAX_VERDICT NF_STOP
24 /* we overload the higher bits for encoding auxiliary data such as the queue
25 * number. Not nice, but better than additional function arguments. */
26 #define NF_VERDICT_MASK 0x0000ffff
27 #define NF_VERDICT_BITS 16
29 #define NF_VERDICT_QMASK 0xffff0000
30 #define NF_VERDICT_QBITS 16
32 #define NF_QUEUE_NR(x) (((x << NF_VERDICT_QBITS) & NF_VERDICT_QMASK) | NF_QUEUE)
34 /* only for userspace compatibility */
36 /* Generic cache responses from hook functions.
37 <= 0x2000 is used for protocol-flags. */
38 #define NFC_UNKNOWN 0x4000
39 #define NFC_ALTERED 0x8000
43 #include <linux/config.h>
44 #ifdef CONFIG_NETFILTER
46 extern void netfilter_init(void);
48 /* Largest hook number + 1 */
49 #define NF_MAX_HOOKS 8
54 typedef unsigned int nf_hookfn(unsigned int hooknum
,
56 const struct net_device
*in
,
57 const struct net_device
*out
,
58 int (*okfn
)(struct sk_buff
*));
62 struct list_head list
;
64 /* User fills in from here down. */
69 /* Hooks are ordered in ascending priority. */
75 struct list_head list
;
79 /* Non-inclusive ranges: use 0/0/NULL to never get called. */
82 int (*set
)(struct sock
*sk
, int optval
, void __user
*user
, unsigned int len
);
83 int (*compat_set
)(struct sock
*sk
, int optval
,
84 void __user
*user
, unsigned int len
);
88 int (*get
)(struct sock
*sk
, int optval
, void __user
*user
, int *len
);
89 int (*compat_get
)(struct sock
*sk
, int optval
,
90 void __user
*user
, int *len
);
92 /* Number of users inside set() or get(). */
94 struct task_struct
*cleanup_task
;
97 /* Each queued (to userspace) skbuff has one of these. */
100 /* The ops struct which sent us to userspace. */
101 struct nf_hook_ops
*elem
;
103 /* If we're sent to userspace, this keeps housekeeping info */
106 struct net_device
*indev
, *outdev
;
107 int (*okfn
)(struct sk_buff
*);
110 /* Function to register/unregister hook points. */
111 int nf_register_hook(struct nf_hook_ops
*reg
);
112 void nf_unregister_hook(struct nf_hook_ops
*reg
);
114 /* Functions to register get/setsockopt ranges (non-inclusive). You
115 need to check permissions yourself! */
116 int nf_register_sockopt(struct nf_sockopt_ops
*reg
);
117 void nf_unregister_sockopt(struct nf_sockopt_ops
*reg
);
119 extern struct list_head nf_hooks
[NPROTO
][NF_MAX_HOOKS
];
121 /* those NF_LOG_* defines and struct nf_loginfo are legacy definitios that will
122 * disappear once iptables is replaced with pkttables. Please DO NOT use them
123 * for any new code! */
124 #define NF_LOG_TCPSEQ 0x01 /* Log TCP sequence numbers */
125 #define NF_LOG_TCPOPT 0x02 /* Log TCP options */
126 #define NF_LOG_IPOPT 0x04 /* Log IP options */
127 #define NF_LOG_UID 0x08 /* Log UID owning local socket */
128 #define NF_LOG_MASK 0x0f
130 #define NF_LOG_TYPE_LOG 0x01
131 #define NF_LOG_TYPE_ULOG 0x02
139 u_int16_t qthreshold
;
148 typedef void nf_logfn(unsigned int pf
,
149 unsigned int hooknum
,
150 const struct sk_buff
*skb
,
151 const struct net_device
*in
,
152 const struct net_device
*out
,
153 const struct nf_loginfo
*li
,
162 /* Function to register/unregister log function. */
163 int nf_log_register(int pf
, struct nf_logger
*logger
);
164 int nf_log_unregister_pf(int pf
);
165 void nf_log_unregister_logger(struct nf_logger
*logger
);
167 /* Calls the registered backend logging function */
168 void nf_log_packet(int pf
,
169 unsigned int hooknum
,
170 const struct sk_buff
*skb
,
171 const struct net_device
*in
,
172 const struct net_device
*out
,
173 struct nf_loginfo
*li
,
174 const char *fmt
, ...);
176 int nf_hook_slow(int pf
, unsigned int hook
, struct sk_buff
**pskb
,
177 struct net_device
*indev
, struct net_device
*outdev
,
178 int (*okfn
)(struct sk_buff
*), int thresh
);
181 * nf_hook_thresh - call a netfilter hook
183 * Returns 1 if the hook has allowed the packet to pass. The function
184 * okfn must be invoked by the caller in this case. Any other return
185 * value indicates the packet has been consumed by the hook.
187 static inline int nf_hook_thresh(int pf
, unsigned int hook
,
188 struct sk_buff
**pskb
,
189 struct net_device
*indev
,
190 struct net_device
*outdev
,
191 int (*okfn
)(struct sk_buff
*), int thresh
,
196 #ifndef CONFIG_NETFILTER_DEBUG
197 if (list_empty(&nf_hooks
[pf
][hook
]))
200 return nf_hook_slow(pf
, hook
, pskb
, indev
, outdev
, okfn
, thresh
);
203 static inline int nf_hook(int pf
, unsigned int hook
, struct sk_buff
**pskb
,
204 struct net_device
*indev
, struct net_device
*outdev
,
205 int (*okfn
)(struct sk_buff
*))
207 return nf_hook_thresh(pf
, hook
, pskb
, indev
, outdev
, okfn
, INT_MIN
, 1);
210 /* Activate hook; either okfn or kfree_skb called, unless a hook
211 returns NF_STOLEN (in which case, it's up to the hook to deal with
214 Returns -ERRNO if packet dropped. Zero means queued, stolen or
219 > I don't want nf_hook to return anything because people might forget
220 > about async and trust the return value to mean "packet was ok".
223 Just document it clearly, then you can expect some sense from kernel
227 /* This is gross, but inline doesn't cut it for avoiding the function
228 call in fast path: gcc doesn't inline (needs value tracking?). --RR */
230 /* HX: It's slightly less gross now. */
232 #define NF_HOOK_THRESH(pf, hook, skb, indev, outdev, okfn, thresh) \
234 if ((__ret=nf_hook_thresh(pf, hook, &(skb), indev, outdev, okfn, thresh, 1)) == 1)\
235 __ret = (okfn)(skb); \
238 #define NF_HOOK_COND(pf, hook, skb, indev, outdev, okfn, cond) \
240 if ((__ret=nf_hook_thresh(pf, hook, &(skb), indev, outdev, okfn, INT_MIN, cond)) == 1)\
241 __ret = (okfn)(skb); \
244 #define NF_HOOK(pf, hook, skb, indev, outdev, okfn) \
245 NF_HOOK_THRESH(pf, hook, skb, indev, outdev, okfn, INT_MIN)
247 /* Call setsockopt() */
248 int nf_setsockopt(struct sock
*sk
, int pf
, int optval
, char __user
*opt
,
250 int nf_getsockopt(struct sock
*sk
, int pf
, int optval
, char __user
*opt
,
253 int compat_nf_setsockopt(struct sock
*sk
, int pf
, int optval
,
254 char __user
*opt
, int len
);
255 int compat_nf_getsockopt(struct sock
*sk
, int pf
, int optval
,
256 char __user
*opt
, int *len
);
259 struct nf_queue_handler
{
260 int (*outfn
)(struct sk_buff
*skb
, struct nf_info
*info
,
261 unsigned int queuenum
, void *data
);
265 extern int nf_register_queue_handler(int pf
,
266 struct nf_queue_handler
*qh
);
267 extern int nf_unregister_queue_handler(int pf
);
268 extern void nf_unregister_queue_handlers(struct nf_queue_handler
*qh
);
269 extern void nf_reinject(struct sk_buff
*skb
,
270 struct nf_info
*info
,
271 unsigned int verdict
);
273 extern void (*ip_ct_attach
)(struct sk_buff
*, struct sk_buff
*);
274 extern void nf_ct_attach(struct sk_buff
*, struct sk_buff
*);
276 /* FIXME: Before cache is ever used, this must be implemented for real. */
277 extern void nf_invalidate_cache(int pf
);
279 /* Call this before modifying an existing packet: ensures it is
280 modifiable and linear to the point you care about (writable_len).
281 Returns true or false. */
282 extern int skb_make_writable(struct sk_buff
**pskb
, unsigned int writable_len
);
284 struct nf_queue_rerouter
{
285 void (*save
)(const struct sk_buff
*skb
, struct nf_info
*info
);
286 int (*reroute
)(struct sk_buff
**skb
, const struct nf_info
*info
);
290 #define nf_info_reroute(x) ((void *)x + sizeof(struct nf_info))
292 extern int nf_register_queue_rerouter(int pf
, struct nf_queue_rerouter
*rer
);
293 extern int nf_unregister_queue_rerouter(int pf
);
295 #include <net/flow.h>
296 extern void (*ip_nat_decode_session
)(struct sk_buff
*, struct flowi
*);
299 nf_nat_decode_session(struct sk_buff
*skb
, struct flowi
*fl
, int family
)
301 #ifdef CONFIG_IP_NF_NAT_NEEDED
302 void (*decodefn
)(struct sk_buff
*, struct flowi
*);
304 if (family
== AF_INET
&& (decodefn
= ip_nat_decode_session
) != NULL
)
309 #ifdef CONFIG_PROC_FS
310 #include <linux/proc_fs.h>
311 extern struct proc_dir_entry
*proc_net_netfilter
;
314 #else /* !CONFIG_NETFILTER */
315 #define NF_HOOK(pf, hook, skb, indev, outdev, okfn) (okfn)(skb)
316 #define NF_HOOK_COND(pf, hook, skb, indev, outdev, okfn, cond) (okfn)(skb)
317 static inline int nf_hook_thresh(int pf
, unsigned int hook
,
318 struct sk_buff
**pskb
,
319 struct net_device
*indev
,
320 struct net_device
*outdev
,
321 int (*okfn
)(struct sk_buff
*), int thresh
,
326 static inline int nf_hook(int pf
, unsigned int hook
, struct sk_buff
**pskb
,
327 struct net_device
*indev
, struct net_device
*outdev
,
328 int (*okfn
)(struct sk_buff
*))
332 static inline void nf_ct_attach(struct sk_buff
*new, struct sk_buff
*skb
) {}
335 nf_nat_decode_session(struct sk_buff
*skb
, struct flowi
*fl
, int family
) {}
336 #endif /*CONFIG_NETFILTER*/
338 #endif /*__KERNEL__*/
339 #endif /*__LINUX_NETFILTER_H*/