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 {
53 struct net_device *in;
54 struct net_device *out;
57 int (*okfn)(struct net *, struct sock *, struct sk_buff *);
60 typedef unsigned int nf_hookfn(void *priv,
62 const struct nf_hook_state *state);
64 /* User fills in from here down. */
66 struct net_device *dev;
70 /* Hooks are ordered in ascending priority. */
74 struct nf_hook_entry {
79 struct nf_hook_entries {
82 struct nf_hook_entry hooks[];
84 /* trailer: pointers to original orig_ops of each hook.
86 * This is not part of struct nf_hook_entry since its only
87 * needed in slow path (hook register/unregister).
89 * const struct nf_hook_ops *orig_ops[]
93 static inline struct nf_hook_ops **nf_hook_entries_get_hook_ops(const struct nf_hook_entries *e)
95 unsigned int n = e->num_hook_entries;
98 hook_end = &e->hooks[n]; /* this is *past* ->hooks[]! */
100 return (struct nf_hook_ops **)hook_end;
104 nf_hook_entry_hookfn(const struct nf_hook_entry *entry, struct sk_buff *skb,
105 struct nf_hook_state *state)
107 return entry->hook(entry->priv, skb, state);
110 static inline void nf_hook_state_init(struct nf_hook_state *p,
113 struct net_device *indev,
114 struct net_device *outdev,
117 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
130 struct nf_sockopt_ops {
131 struct list_head list;
135 /* Non-inclusive ranges: use 0/0/NULL to never get called. */
138 int (*set)(struct sock *sk, int optval, void __user *user, unsigned int len);
140 int (*compat_set)(struct sock *sk, int optval,
141 void __user *user, unsigned int len);
145 int (*get)(struct sock *sk, int optval, void __user *user, int *len);
147 int (*compat_get)(struct sock *sk, int optval,
148 void __user *user, int *len);
150 /* Use the module struct to lock set/get code in place */
151 struct module *owner;
154 /* Function to register/unregister hook points. */
155 int nf_register_net_hook(struct net *net, const struct nf_hook_ops *ops);
156 void nf_unregister_net_hook(struct net *net, const struct nf_hook_ops *ops);
157 int nf_register_net_hooks(struct net *net, const struct nf_hook_ops *reg,
159 void nf_unregister_net_hooks(struct net *net, const struct nf_hook_ops *reg,
162 /* Functions to register get/setsockopt ranges (non-inclusive). You
163 need to check permissions yourself! */
164 int nf_register_sockopt(struct nf_sockopt_ops *reg);
165 void nf_unregister_sockopt(struct nf_sockopt_ops *reg);
167 #ifdef HAVE_JUMP_LABEL
168 extern struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS];
171 int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state,
172 const struct nf_hook_entries *e, unsigned int i);
175 * nf_hook - call a netfilter hook
177 * Returns 1 if the hook has allowed the packet to pass. The function
178 * okfn must be invoked by the caller in this case. Any other return
179 * value indicates the packet has been consumed by the hook.
181 static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
182 struct sock *sk, struct sk_buff *skb,
183 struct net_device *indev, struct net_device *outdev,
184 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
186 struct nf_hook_entries *hook_head;
189 #ifdef HAVE_JUMP_LABEL
190 if (__builtin_constant_p(pf) &&
191 __builtin_constant_p(hook) &&
192 !static_key_false(&nf_hooks_needed[pf][hook]))
197 hook_head = rcu_dereference(net->nf.hooks[pf][hook]);
199 struct nf_hook_state state;
201 nf_hook_state_init(&state, hook, pf, indev, outdev,
204 ret = nf_hook_slow(skb, &state, hook_head, 0);
211 /* Activate hook; either okfn or kfree_skb called, unless a hook
212 returns NF_STOLEN (in which case, it's up to the hook to deal with
215 Returns -ERRNO if packet dropped. Zero means queued, stolen or
220 > I don't want nf_hook to return anything because people might forget
221 > about async and trust the return value to mean "packet was ok".
224 Just document it clearly, then you can expect some sense from kernel
229 NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
230 struct sk_buff *skb, struct net_device *in, struct net_device *out,
231 int (*okfn)(struct net *, struct sock *, struct sk_buff *),
237 ((ret = nf_hook(pf, hook, net, sk, skb, in, out, okfn)) == 1))
238 ret = okfn(net, sk, skb);
243 NF_HOOK(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk, struct sk_buff *skb,
244 struct net_device *in, struct net_device *out,
245 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
247 int ret = nf_hook(pf, hook, net, sk, skb, in, out, okfn);
249 ret = okfn(net, sk, skb);
253 /* Call setsockopt() */
254 int nf_setsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt,
256 int nf_getsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt,
259 int compat_nf_setsockopt(struct sock *sk, u_int8_t pf, int optval,
260 char __user *opt, unsigned int len);
261 int compat_nf_getsockopt(struct sock *sk, u_int8_t pf, int optval,
262 char __user *opt, int *len);
265 /* Call this before modifying an existing packet: ensures it is
266 modifiable and linear to the point you care about (writable_len).
267 Returns true or false. */
268 int skb_make_writable(struct sk_buff *skb, unsigned int writable_len);
271 struct nf_queue_entry;
274 unsigned short family;
275 __sum16 (*checksum)(struct sk_buff *skb, unsigned int hook,
276 unsigned int dataoff, u_int8_t protocol);
277 __sum16 (*checksum_partial)(struct sk_buff *skb,
279 unsigned int dataoff,
282 int (*route)(struct net *net, struct dst_entry **dst,
283 struct flowi *fl, bool strict);
284 void (*saveroute)(const struct sk_buff *skb,
285 struct nf_queue_entry *entry);
286 int (*reroute)(struct net *net, struct sk_buff *skb,
287 const struct nf_queue_entry *entry);
291 extern const struct nf_afinfo __rcu *nf_afinfo[NFPROTO_NUMPROTO];
292 static inline const struct nf_afinfo *nf_get_afinfo(unsigned short family)
294 return rcu_dereference(nf_afinfo[family]);
297 static inline __sum16
298 nf_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff,
299 u_int8_t protocol, unsigned short family)
301 const struct nf_afinfo *afinfo;
305 afinfo = nf_get_afinfo(family);
307 csum = afinfo->checksum(skb, hook, dataoff, protocol);
312 static inline __sum16
313 nf_checksum_partial(struct sk_buff *skb, unsigned int hook,
314 unsigned int dataoff, unsigned int len,
315 u_int8_t protocol, unsigned short family)
317 const struct nf_afinfo *afinfo;
321 afinfo = nf_get_afinfo(family);
323 csum = afinfo->checksum_partial(skb, hook, dataoff, len,
329 int nf_register_afinfo(const struct nf_afinfo *afinfo);
330 void nf_unregister_afinfo(const struct nf_afinfo *afinfo);
332 #include <net/flow.h>
333 extern void (*nf_nat_decode_session_hook)(struct sk_buff *, struct flowi *);
336 nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family)
338 #ifdef CONFIG_NF_NAT_NEEDED
339 void (*decodefn)(struct sk_buff *, struct flowi *);
342 decodefn = rcu_dereference(nf_nat_decode_session_hook);
349 #else /* !CONFIG_NETFILTER */
351 NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
352 struct sk_buff *skb, struct net_device *in, struct net_device *out,
353 int (*okfn)(struct net *, struct sock *, struct sk_buff *),
356 return okfn(net, sk, skb);
360 NF_HOOK(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
361 struct sk_buff *skb, struct net_device *in, struct net_device *out,
362 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
364 return okfn(net, sk, skb);
367 static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
368 struct sock *sk, struct sk_buff *skb,
369 struct net_device *indev, struct net_device *outdev,
370 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
376 nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family)
379 #endif /*CONFIG_NETFILTER*/
381 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
382 #include <linux/netfilter/nf_conntrack_zones_common.h>
384 extern void (*ip_ct_attach)(struct sk_buff *, const struct sk_buff *) __rcu;
385 void nf_ct_attach(struct sk_buff *, const struct sk_buff *);
386 extern void (*nf_ct_destroy)(struct nf_conntrack *) __rcu;
388 static inline void nf_ct_attach(struct sk_buff *new, struct sk_buff *skb) {}
392 enum ip_conntrack_info;
395 struct nfnl_ct_hook {
396 struct nf_conn *(*get_ct)(const struct sk_buff *skb,
397 enum ip_conntrack_info *ctinfo);
398 size_t (*build_size)(const struct nf_conn *ct);
399 int (*build)(struct sk_buff *skb, struct nf_conn *ct,
400 enum ip_conntrack_info ctinfo,
401 u_int16_t ct_attr, u_int16_t ct_info_attr);
402 int (*parse)(const struct nlattr *attr, struct nf_conn *ct);
403 int (*attach_expect)(const struct nlattr *attr, struct nf_conn *ct,
404 u32 portid, u32 report);
405 void (*seq_adjust)(struct sk_buff *skb, struct nf_conn *ct,
406 enum ip_conntrack_info ctinfo, s32 off);
408 extern struct nfnl_ct_hook __rcu *nfnl_ct_hook;
411 * nf_skb_duplicated - TEE target has sent a packet
413 * When a xtables target sends a packet, the OUTPUT and POSTROUTING
414 * hooks are traversed again, i.e. nft and xtables are invoked recursively.
416 * This is used by xtables TEE target to prevent the duplicated skb from
417 * being duplicated again.
419 DECLARE_PER_CPU(bool, nf_skb_duplicated);
421 #endif /*__LINUX_NETFILTER_H*/