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 struct list_head list;
66 /* User fills in from here down. */
68 struct net_device *dev;
72 /* Hooks are ordered in ascending priority. */
76 struct nf_hook_entry {
77 struct nf_hook_entry __rcu *next;
80 const struct nf_hook_ops *orig_ops;
84 nf_hook_entry_init(struct nf_hook_entry *entry, const struct nf_hook_ops *ops)
87 entry->hook = ops->hook;
88 entry->priv = ops->priv;
89 entry->orig_ops = ops;
93 nf_hook_entry_priority(const struct nf_hook_entry *entry)
95 return entry->orig_ops->priority;
99 nf_hook_entry_hookfn(const struct nf_hook_entry *entry, struct sk_buff *skb,
100 struct nf_hook_state *state)
102 return entry->hook(entry->priv, skb, state);
105 static inline const struct nf_hook_ops *
106 nf_hook_entry_ops(const struct nf_hook_entry *entry)
108 return entry->orig_ops;
111 static inline void nf_hook_state_init(struct nf_hook_state *p,
114 struct net_device *indev,
115 struct net_device *outdev,
118 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
131 struct nf_sockopt_ops {
132 struct list_head list;
136 /* Non-inclusive ranges: use 0/0/NULL to never get called. */
139 int (*set)(struct sock *sk, int optval, void __user *user, unsigned int len);
141 int (*compat_set)(struct sock *sk, int optval,
142 void __user *user, unsigned int len);
146 int (*get)(struct sock *sk, int optval, void __user *user, int *len);
148 int (*compat_get)(struct sock *sk, int optval,
149 void __user *user, int *len);
151 /* Use the module struct to lock set/get code in place */
152 struct module *owner;
155 /* Function to register/unregister hook points. */
156 int nf_register_net_hook(struct net *net, const struct nf_hook_ops *ops);
157 void nf_unregister_net_hook(struct net *net, const struct nf_hook_ops *ops);
158 int nf_register_net_hooks(struct net *net, const struct nf_hook_ops *reg,
160 void nf_unregister_net_hooks(struct net *net, const struct nf_hook_ops *reg,
163 int nf_register_hook(struct nf_hook_ops *reg);
164 void nf_unregister_hook(struct nf_hook_ops *reg);
165 int nf_register_hooks(struct nf_hook_ops *reg, unsigned int n);
166 void nf_unregister_hooks(struct nf_hook_ops *reg, unsigned int n);
167 int _nf_register_hooks(struct nf_hook_ops *reg, unsigned int n);
168 void _nf_unregister_hooks(struct nf_hook_ops *reg, unsigned int n);
170 /* Functions to register get/setsockopt ranges (non-inclusive). You
171 need to check permissions yourself! */
172 int nf_register_sockopt(struct nf_sockopt_ops *reg);
173 void nf_unregister_sockopt(struct nf_sockopt_ops *reg);
175 #ifdef HAVE_JUMP_LABEL
176 extern struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS];
179 int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state,
180 struct nf_hook_entry *entry);
183 * nf_hook - call a netfilter hook
185 * Returns 1 if the hook has allowed the packet to pass. The function
186 * okfn must be invoked by the caller in this case. Any other return
187 * value indicates the packet has been consumed by the hook.
189 static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
190 struct sock *sk, struct sk_buff *skb,
191 struct net_device *indev, struct net_device *outdev,
192 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
194 struct nf_hook_entry *hook_head;
197 #ifdef HAVE_JUMP_LABEL
198 if (__builtin_constant_p(pf) &&
199 __builtin_constant_p(hook) &&
200 !static_key_false(&nf_hooks_needed[pf][hook]))
205 hook_head = rcu_dereference(net->nf.hooks[pf][hook]);
207 struct nf_hook_state state;
209 nf_hook_state_init(&state, hook, pf, indev, outdev,
212 ret = nf_hook_slow(skb, &state, hook_head);
219 /* Activate hook; either okfn or kfree_skb called, unless a hook
220 returns NF_STOLEN (in which case, it's up to the hook to deal with
223 Returns -ERRNO if packet dropped. Zero means queued, stolen or
228 > I don't want nf_hook to return anything because people might forget
229 > about async and trust the return value to mean "packet was ok".
232 Just document it clearly, then you can expect some sense from kernel
237 NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
238 struct sk_buff *skb, struct net_device *in, struct net_device *out,
239 int (*okfn)(struct net *, struct sock *, struct sk_buff *),
245 ((ret = nf_hook(pf, hook, net, sk, skb, in, out, okfn)) == 1))
246 ret = okfn(net, sk, skb);
251 NF_HOOK(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk, struct sk_buff *skb,
252 struct net_device *in, struct net_device *out,
253 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
255 int ret = nf_hook(pf, hook, net, sk, skb, in, out, okfn);
257 ret = okfn(net, sk, skb);
261 /* Call setsockopt() */
262 int nf_setsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt,
264 int nf_getsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt,
267 int compat_nf_setsockopt(struct sock *sk, u_int8_t pf, int optval,
268 char __user *opt, unsigned int len);
269 int compat_nf_getsockopt(struct sock *sk, u_int8_t pf, int optval,
270 char __user *opt, int *len);
273 /* Call this before modifying an existing packet: ensures it is
274 modifiable and linear to the point you care about (writable_len).
275 Returns true or false. */
276 int skb_make_writable(struct sk_buff *skb, unsigned int writable_len);
279 struct nf_queue_entry;
282 unsigned short family;
283 __sum16 (*checksum)(struct sk_buff *skb, unsigned int hook,
284 unsigned int dataoff, u_int8_t protocol);
285 __sum16 (*checksum_partial)(struct sk_buff *skb,
287 unsigned int dataoff,
290 int (*route)(struct net *net, struct dst_entry **dst,
291 struct flowi *fl, bool strict);
292 void (*saveroute)(const struct sk_buff *skb,
293 struct nf_queue_entry *entry);
294 int (*reroute)(struct net *net, struct sk_buff *skb,
295 const struct nf_queue_entry *entry);
299 extern const struct nf_afinfo __rcu *nf_afinfo[NFPROTO_NUMPROTO];
300 static inline const struct nf_afinfo *nf_get_afinfo(unsigned short family)
302 return rcu_dereference(nf_afinfo[family]);
305 static inline __sum16
306 nf_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff,
307 u_int8_t protocol, unsigned short family)
309 const struct nf_afinfo *afinfo;
313 afinfo = nf_get_afinfo(family);
315 csum = afinfo->checksum(skb, hook, dataoff, protocol);
320 static inline __sum16
321 nf_checksum_partial(struct sk_buff *skb, unsigned int hook,
322 unsigned int dataoff, unsigned int len,
323 u_int8_t protocol, unsigned short family)
325 const struct nf_afinfo *afinfo;
329 afinfo = nf_get_afinfo(family);
331 csum = afinfo->checksum_partial(skb, hook, dataoff, len,
337 int nf_register_afinfo(const struct nf_afinfo *afinfo);
338 void nf_unregister_afinfo(const struct nf_afinfo *afinfo);
340 #include <net/flow.h>
341 extern void (*nf_nat_decode_session_hook)(struct sk_buff *, struct flowi *);
344 nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family)
346 #ifdef CONFIG_NF_NAT_NEEDED
347 void (*decodefn)(struct sk_buff *, struct flowi *);
350 decodefn = rcu_dereference(nf_nat_decode_session_hook);
357 #else /* !CONFIG_NETFILTER */
359 NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
360 struct sk_buff *skb, struct net_device *in, struct net_device *out,
361 int (*okfn)(struct net *, struct sock *, struct sk_buff *),
364 return okfn(net, sk, skb);
368 NF_HOOK(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
369 struct sk_buff *skb, struct net_device *in, struct net_device *out,
370 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
372 return okfn(net, sk, skb);
375 static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
376 struct sock *sk, struct sk_buff *skb,
377 struct net_device *indev, struct net_device *outdev,
378 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
384 nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family)
387 #endif /*CONFIG_NETFILTER*/
389 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
390 #include <linux/netfilter/nf_conntrack_zones_common.h>
392 extern void (*ip_ct_attach)(struct sk_buff *, const struct sk_buff *) __rcu;
393 void nf_ct_attach(struct sk_buff *, const struct sk_buff *);
394 extern void (*nf_ct_destroy)(struct nf_conntrack *) __rcu;
396 static inline void nf_ct_attach(struct sk_buff *new, struct sk_buff *skb) {}
400 enum ip_conntrack_info;
403 struct nfnl_ct_hook {
404 struct nf_conn *(*get_ct)(const struct sk_buff *skb,
405 enum ip_conntrack_info *ctinfo);
406 size_t (*build_size)(const struct nf_conn *ct);
407 int (*build)(struct sk_buff *skb, struct nf_conn *ct,
408 enum ip_conntrack_info ctinfo,
409 u_int16_t ct_attr, u_int16_t ct_info_attr);
410 int (*parse)(const struct nlattr *attr, struct nf_conn *ct);
411 int (*attach_expect)(const struct nlattr *attr, struct nf_conn *ct,
412 u32 portid, u32 report);
413 void (*seq_adjust)(struct sk_buff *skb, struct nf_conn *ct,
414 enum ip_conntrack_info ctinfo, s32 off);
416 extern struct nfnl_ct_hook __rcu *nfnl_ct_hook;
419 * nf_skb_duplicated - TEE target has sent a packet
421 * When a xtables target sends a packet, the OUTPUT and POSTROUTING
422 * hooks are traversed again, i.e. nft and xtables are invoked recursively.
424 * This is used by xtables TEE target to prevent the duplicated skb from
425 * being duplicated again.
427 DECLARE_PER_CPU(bool, nf_skb_duplicated);
429 #endif /*__LINUX_NETFILTER_H*/