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 <linux/netfilter_defs.h>
14 #include <linux/netdevice.h>
15 #include <net/net_namespace.h>
17 #ifdef CONFIG_NETFILTER
18 static inline int NF_DROP_GETERR(int verdict)
20 return -(verdict >> NF_VERDICT_QBITS);
23 static inline int nf_inet_addr_cmp(const union nf_inet_addr *a1,
24 const union nf_inet_addr *a2)
26 return a1->all[0] == a2->all[0] &&
27 a1->all[1] == a2->all[1] &&
28 a1->all[2] == a2->all[2] &&
29 a1->all[3] == a2->all[3];
32 static inline void nf_inet_addr_mask(const union nf_inet_addr *a1,
33 union nf_inet_addr *result,
34 const union nf_inet_addr *mask)
36 result->all[0] = a1->all[0] & mask->all[0];
37 result->all[1] = a1->all[1] & mask->all[1];
38 result->all[2] = a1->all[2] & mask->all[2];
39 result->all[3] = a1->all[3] & mask->all[3];
42 int netfilter_init(void);
50 struct nf_hook_state {
54 struct net_device *in;
55 struct net_device *out;
58 struct list_head *hook_list;
59 int (*okfn)(struct net *, struct sock *, struct sk_buff *);
62 static inline void nf_hook_state_init(struct nf_hook_state *p,
63 struct list_head *hook_list,
65 int thresh, u_int8_t pf,
66 struct net_device *indev,
67 struct net_device *outdev,
70 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
79 p->hook_list = hook_list;
83 typedef unsigned int nf_hookfn(void *priv,
85 const struct nf_hook_state *state);
88 struct list_head list;
90 /* User fills in from here down. */
92 struct net_device *dev;
96 /* Hooks are ordered in ascending priority. */
100 struct nf_sockopt_ops {
101 struct list_head list;
105 /* Non-inclusive ranges: use 0/0/NULL to never get called. */
108 int (*set)(struct sock *sk, int optval, void __user *user, unsigned int len);
110 int (*compat_set)(struct sock *sk, int optval,
111 void __user *user, unsigned int len);
115 int (*get)(struct sock *sk, int optval, void __user *user, int *len);
117 int (*compat_get)(struct sock *sk, int optval,
118 void __user *user, int *len);
120 /* Use the module struct to lock set/get code in place */
121 struct module *owner;
124 /* Function to register/unregister hook points. */
125 int nf_register_net_hook(struct net *net, const struct nf_hook_ops *ops);
126 void nf_unregister_net_hook(struct net *net, const struct nf_hook_ops *ops);
127 int nf_register_net_hooks(struct net *net, const struct nf_hook_ops *reg,
129 void nf_unregister_net_hooks(struct net *net, const struct nf_hook_ops *reg,
132 int nf_register_hook(struct nf_hook_ops *reg);
133 void nf_unregister_hook(struct nf_hook_ops *reg);
134 int nf_register_hooks(struct nf_hook_ops *reg, unsigned int n);
135 void nf_unregister_hooks(struct nf_hook_ops *reg, unsigned int n);
137 /* Functions to register get/setsockopt ranges (non-inclusive). You
138 need to check permissions yourself! */
139 int nf_register_sockopt(struct nf_sockopt_ops *reg);
140 void nf_unregister_sockopt(struct nf_sockopt_ops *reg);
142 #ifdef HAVE_JUMP_LABEL
143 extern struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS];
146 int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state);
149 * nf_hook_thresh - call a netfilter hook
151 * Returns 1 if the hook has allowed the packet to pass. The function
152 * okfn must be invoked by the caller in this case. Any other return
153 * value indicates the packet has been consumed by the hook.
155 static inline int nf_hook_thresh(u_int8_t pf, unsigned int hook,
159 struct net_device *indev,
160 struct net_device *outdev,
161 int (*okfn)(struct net *, struct sock *, struct sk_buff *),
164 struct list_head *hook_list;
166 #ifdef HAVE_JUMP_LABEL
167 if (__builtin_constant_p(pf) &&
168 __builtin_constant_p(hook) &&
169 !static_key_false(&nf_hooks_needed[pf][hook]))
173 hook_list = &net->nf.hooks[pf][hook];
175 if (!list_empty(hook_list)) {
176 struct nf_hook_state state;
178 nf_hook_state_init(&state, hook_list, hook, thresh,
179 pf, indev, outdev, sk, net, okfn);
180 return nf_hook_slow(skb, &state);
185 static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
186 struct sock *sk, struct sk_buff *skb,
187 struct net_device *indev, struct net_device *outdev,
188 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
190 return nf_hook_thresh(pf, hook, net, sk, skb, indev, outdev, okfn, INT_MIN);
193 /* Activate hook; either okfn or kfree_skb called, unless a hook
194 returns NF_STOLEN (in which case, it's up to the hook to deal with
197 Returns -ERRNO if packet dropped. Zero means queued, stolen or
202 > I don't want nf_hook to return anything because people might forget
203 > about async and trust the return value to mean "packet was ok".
206 Just document it clearly, then you can expect some sense from kernel
211 NF_HOOK_THRESH(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
212 struct sk_buff *skb, struct net_device *in,
213 struct net_device *out,
214 int (*okfn)(struct net *, struct sock *, struct sk_buff *),
217 int ret = nf_hook_thresh(pf, hook, net, sk, skb, in, out, okfn, thresh);
219 ret = okfn(net, sk, skb);
224 NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
225 struct sk_buff *skb, struct net_device *in, struct net_device *out,
226 int (*okfn)(struct net *, struct sock *, struct sk_buff *),
232 ((ret = nf_hook_thresh(pf, hook, net, sk, skb, in, out, okfn, INT_MIN)) == 1))
233 ret = okfn(net, sk, skb);
238 NF_HOOK(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk, struct sk_buff *skb,
239 struct net_device *in, struct net_device *out,
240 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
242 return NF_HOOK_THRESH(pf, hook, net, sk, skb, in, out, okfn, INT_MIN);
245 /* Call setsockopt() */
246 int nf_setsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt,
248 int nf_getsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt,
251 int compat_nf_setsockopt(struct sock *sk, u_int8_t pf, int optval,
252 char __user *opt, unsigned int len);
253 int compat_nf_getsockopt(struct sock *sk, u_int8_t pf, int optval,
254 char __user *opt, int *len);
257 /* Call this before modifying an existing packet: ensures it is
258 modifiable and linear to the point you care about (writable_len).
259 Returns true or false. */
260 int skb_make_writable(struct sk_buff *skb, unsigned int writable_len);
263 struct nf_queue_entry;
266 unsigned short family;
267 __sum16 (*checksum)(struct sk_buff *skb, unsigned int hook,
268 unsigned int dataoff, u_int8_t protocol);
269 __sum16 (*checksum_partial)(struct sk_buff *skb,
271 unsigned int dataoff,
274 int (*route)(struct net *net, struct dst_entry **dst,
275 struct flowi *fl, bool strict);
276 void (*saveroute)(const struct sk_buff *skb,
277 struct nf_queue_entry *entry);
278 int (*reroute)(struct net *net, struct sk_buff *skb,
279 const struct nf_queue_entry *entry);
283 extern const struct nf_afinfo __rcu *nf_afinfo[NFPROTO_NUMPROTO];
284 static inline const struct nf_afinfo *nf_get_afinfo(unsigned short family)
286 return rcu_dereference(nf_afinfo[family]);
289 static inline __sum16
290 nf_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff,
291 u_int8_t protocol, unsigned short family)
293 const struct nf_afinfo *afinfo;
297 afinfo = nf_get_afinfo(family);
299 csum = afinfo->checksum(skb, hook, dataoff, protocol);
304 static inline __sum16
305 nf_checksum_partial(struct sk_buff *skb, unsigned int hook,
306 unsigned int dataoff, unsigned int len,
307 u_int8_t protocol, unsigned short family)
309 const struct nf_afinfo *afinfo;
313 afinfo = nf_get_afinfo(family);
315 csum = afinfo->checksum_partial(skb, hook, dataoff, len,
321 int nf_register_afinfo(const struct nf_afinfo *afinfo);
322 void nf_unregister_afinfo(const struct nf_afinfo *afinfo);
324 #include <net/flow.h>
325 extern void (*nf_nat_decode_session_hook)(struct sk_buff *, struct flowi *);
328 nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family)
330 #ifdef CONFIG_NF_NAT_NEEDED
331 void (*decodefn)(struct sk_buff *, struct flowi *);
334 decodefn = rcu_dereference(nf_nat_decode_session_hook);
341 #else /* !CONFIG_NETFILTER */
343 NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
344 struct sk_buff *skb, struct net_device *in, struct net_device *out,
345 int (*okfn)(struct net *, struct sock *, struct sk_buff *),
348 return okfn(net, sk, skb);
352 NF_HOOK(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
353 struct sk_buff *skb, struct net_device *in, struct net_device *out,
354 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
356 return okfn(net, sk, skb);
359 static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
360 struct sock *sk, struct sk_buff *skb,
361 struct net_device *indev, struct net_device *outdev,
362 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
368 nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family)
371 #endif /*CONFIG_NETFILTER*/
373 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
374 #include <linux/netfilter/nf_conntrack_zones_common.h>
376 extern void (*ip_ct_attach)(struct sk_buff *, const struct sk_buff *) __rcu;
377 void nf_ct_attach(struct sk_buff *, const struct sk_buff *);
378 extern void (*nf_ct_destroy)(struct nf_conntrack *) __rcu;
380 static inline void nf_ct_attach(struct sk_buff *new, struct sk_buff *skb) {}
384 enum ip_conntrack_info;
387 struct nfnl_ct_hook {
388 struct nf_conn *(*get_ct)(const struct sk_buff *skb,
389 enum ip_conntrack_info *ctinfo);
390 size_t (*build_size)(const struct nf_conn *ct);
391 int (*build)(struct sk_buff *skb, struct nf_conn *ct,
392 enum ip_conntrack_info ctinfo,
393 u_int16_t ct_attr, u_int16_t ct_info_attr);
394 int (*parse)(const struct nlattr *attr, struct nf_conn *ct);
395 int (*attach_expect)(const struct nlattr *attr, struct nf_conn *ct,
396 u32 portid, u32 report);
397 void (*seq_adjust)(struct sk_buff *skb, struct nf_conn *ct,
398 enum ip_conntrack_info ctinfo, s32 off);
400 extern struct nfnl_ct_hook __rcu *nfnl_ct_hook;
403 * nf_skb_duplicated - TEE target has sent a packet
405 * When a xtables target sends a packet, the OUTPUT and POSTROUTING
406 * hooks are traversed again, i.e. nft and xtables are invoked recursively.
408 * This is used by xtables TEE target to prevent the duplicated skb from
409 * being duplicated again.
411 DECLARE_PER_CPU(bool, nf_skb_duplicated);
413 #endif /*__LINUX_NETFILTER_H*/