1
2#ifndef __LINUX_NETFILTER_H
3#define __LINUX_NETFILTER_H
4
5#include <linux/init.h>
6#include <linux/skbuff.h>
7#include <linux/net.h>
8#include <linux/if.h>
9#include <linux/in.h>
10#include <linux/in6.h>
11#include <linux/wait.h>
12#include <linux/list.h>
13#include <linux/static_key.h>
14#include <linux/netfilter_defs.h>
15#include <linux/netdevice.h>
16#include <net/net_namespace.h>
17
18#ifdef CONFIG_NETFILTER
19static inline int NF_DROP_GETERR(int verdict)
20{
21 return -(verdict >> NF_VERDICT_QBITS);
22}
23
24static inline int nf_inet_addr_cmp(const union nf_inet_addr *a1,
25 const union nf_inet_addr *a2)
26{
27#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
28 const unsigned long *ul1 = (const unsigned long *)a1;
29 const unsigned long *ul2 = (const unsigned long *)a2;
30
31 return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
32#else
33 return a1->all[0] == a2->all[0] &&
34 a1->all[1] == a2->all[1] &&
35 a1->all[2] == a2->all[2] &&
36 a1->all[3] == a2->all[3];
37#endif
38}
39
40static inline void nf_inet_addr_mask(const union nf_inet_addr *a1,
41 union nf_inet_addr *result,
42 const union nf_inet_addr *mask)
43{
44#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
45 const unsigned long *ua = (const unsigned long *)a1;
46 unsigned long *ur = (unsigned long *)result;
47 const unsigned long *um = (const unsigned long *)mask;
48
49 ur[0] = ua[0] & um[0];
50 ur[1] = ua[1] & um[1];
51#else
52 result->all[0] = a1->all[0] & mask->all[0];
53 result->all[1] = a1->all[1] & mask->all[1];
54 result->all[2] = a1->all[2] & mask->all[2];
55 result->all[3] = a1->all[3] & mask->all[3];
56#endif
57}
58
59int netfilter_init(void);
60
61struct sk_buff;
62
63struct nf_hook_ops;
64
65struct sock;
66
67struct nf_hook_state {
68 unsigned int hook;
69 u_int8_t pf;
70 struct net_device *in;
71 struct net_device *out;
72 struct sock *sk;
73 struct net *net;
74 int (*okfn)(struct net *, struct sock *, struct sk_buff *);
75};
76
77typedef unsigned int nf_hookfn(void *priv,
78 struct sk_buff *skb,
79 const struct nf_hook_state *state);
80struct nf_hook_ops {
81
82 nf_hookfn *hook;
83 struct net_device *dev;
84 void *priv;
85 u_int8_t pf;
86 unsigned int hooknum;
87
88 int priority;
89};
90
91struct nf_hook_entry {
92 nf_hookfn *hook;
93 void *priv;
94};
95
96struct nf_hook_entries_rcu_head {
97 struct rcu_head head;
98 void *allocation;
99};
100
101struct nf_hook_entries {
102 u16 num_hook_entries;
103
104 struct nf_hook_entry hooks[];
105
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117
118
119};
120
121static inline struct nf_hook_ops **nf_hook_entries_get_hook_ops(const struct nf_hook_entries *e)
122{
123 unsigned int n = e->num_hook_entries;
124 const void *hook_end;
125
126 hook_end = &e->hooks[n];
127
128 return (struct nf_hook_ops **)hook_end;
129}
130
131static inline int
132nf_hook_entry_hookfn(const struct nf_hook_entry *entry, struct sk_buff *skb,
133 struct nf_hook_state *state)
134{
135 return entry->hook(entry->priv, skb, state);
136}
137
138static inline void nf_hook_state_init(struct nf_hook_state *p,
139 unsigned int hook,
140 u_int8_t pf,
141 struct net_device *indev,
142 struct net_device *outdev,
143 struct sock *sk,
144 struct net *net,
145 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
146{
147 p->hook = hook;
148 p->pf = pf;
149 p->in = indev;
150 p->out = outdev;
151 p->sk = sk;
152 p->net = net;
153 p->okfn = okfn;
154}
155
156
157
158struct nf_sockopt_ops {
159 struct list_head list;
160
161 u_int8_t pf;
162
163
164 int set_optmin;
165 int set_optmax;
166 int (*set)(struct sock *sk, int optval, void __user *user, unsigned int len);
167#ifdef CONFIG_COMPAT
168 int (*compat_set)(struct sock *sk, int optval,
169 void __user *user, unsigned int len);
170#endif
171 int get_optmin;
172 int get_optmax;
173 int (*get)(struct sock *sk, int optval, void __user *user, int *len);
174#ifdef CONFIG_COMPAT
175 int (*compat_get)(struct sock *sk, int optval,
176 void __user *user, int *len);
177#endif
178
179 struct module *owner;
180};
181
182
183int nf_register_net_hook(struct net *net, const struct nf_hook_ops *ops);
184void nf_unregister_net_hook(struct net *net, const struct nf_hook_ops *ops);
185int nf_register_net_hooks(struct net *net, const struct nf_hook_ops *reg,
186 unsigned int n);
187void nf_unregister_net_hooks(struct net *net, const struct nf_hook_ops *reg,
188 unsigned int n);
189
190
191
192int nf_register_sockopt(struct nf_sockopt_ops *reg);
193void nf_unregister_sockopt(struct nf_sockopt_ops *reg);
194
195#ifdef CONFIG_JUMP_LABEL
196extern struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS];
197#endif
198
199int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state,
200 const struct nf_hook_entries *e, unsigned int i);
201
202
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207
208
209static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
210 struct sock *sk, struct sk_buff *skb,
211 struct net_device *indev, struct net_device *outdev,
212 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
213{
214 struct nf_hook_entries *hook_head = NULL;
215 int ret = 1;
216
217#ifdef CONFIG_JUMP_LABEL
218 if (__builtin_constant_p(pf) &&
219 __builtin_constant_p(hook) &&
220 !static_key_false(&nf_hooks_needed[pf][hook]))
221 return 1;
222#endif
223
224 rcu_read_lock();
225 switch (pf) {
226 case NFPROTO_IPV4:
227 hook_head = rcu_dereference(net->nf.hooks_ipv4[hook]);
228 break;
229 case NFPROTO_IPV6:
230 hook_head = rcu_dereference(net->nf.hooks_ipv6[hook]);
231 break;
232 case NFPROTO_ARP:
233#ifdef CONFIG_NETFILTER_FAMILY_ARP
234 if (WARN_ON_ONCE(hook >= ARRAY_SIZE(net->nf.hooks_arp)))
235 break;
236 hook_head = rcu_dereference(net->nf.hooks_arp[hook]);
237#endif
238 break;
239 case NFPROTO_BRIDGE:
240#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE
241 hook_head = rcu_dereference(net->nf.hooks_bridge[hook]);
242#endif
243 break;
244#if IS_ENABLED(CONFIG_DECNET)
245 case NFPROTO_DECNET:
246 hook_head = rcu_dereference(net->nf.hooks_decnet[hook]);
247 break;
248#endif
249 default:
250 WARN_ON_ONCE(1);
251 break;
252 }
253
254 if (hook_head) {
255 struct nf_hook_state state;
256
257 nf_hook_state_init(&state, hook, pf, indev, outdev,
258 sk, net, okfn);
259
260 ret = nf_hook_slow(skb, &state, hook_head, 0);
261 }
262 rcu_read_unlock();
263
264 return ret;
265}
266
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283
284static inline int
285NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
286 struct sk_buff *skb, struct net_device *in, struct net_device *out,
287 int (*okfn)(struct net *, struct sock *, struct sk_buff *),
288 bool cond)
289{
290 int ret;
291
292 if (!cond ||
293 ((ret = nf_hook(pf, hook, net, sk, skb, in, out, okfn)) == 1))
294 ret = okfn(net, sk, skb);
295 return ret;
296}
297
298static inline int
299NF_HOOK(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk, struct sk_buff *skb,
300 struct net_device *in, struct net_device *out,
301 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
302{
303 int ret = nf_hook(pf, hook, net, sk, skb, in, out, okfn);
304 if (ret == 1)
305 ret = okfn(net, sk, skb);
306 return ret;
307}
308
309static inline void
310NF_HOOK_LIST(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
311 struct list_head *head, struct net_device *in, struct net_device *out,
312 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
313{
314 struct sk_buff *skb, *next;
315 struct list_head sublist;
316
317 INIT_LIST_HEAD(&sublist);
318 list_for_each_entry_safe(skb, next, head, list) {
319 list_del(&skb->list);
320 if (nf_hook(pf, hook, net, sk, skb, in, out, okfn) == 1)
321 list_add_tail(&skb->list, &sublist);
322 }
323
324 list_splice(&sublist, head);
325}
326
327
328int nf_setsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt,
329 unsigned int len);
330int nf_getsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt,
331 int *len);
332#ifdef CONFIG_COMPAT
333int compat_nf_setsockopt(struct sock *sk, u_int8_t pf, int optval,
334 char __user *opt, unsigned int len);
335int compat_nf_getsockopt(struct sock *sk, u_int8_t pf, int optval,
336 char __user *opt, int *len);
337#endif
338
339
340
341
342int skb_make_writable(struct sk_buff *skb, unsigned int writable_len);
343
344struct flowi;
345struct nf_queue_entry;
346
347__sum16 nf_checksum(struct sk_buff *skb, unsigned int hook,
348 unsigned int dataoff, u_int8_t protocol,
349 unsigned short family);
350
351__sum16 nf_checksum_partial(struct sk_buff *skb, unsigned int hook,
352 unsigned int dataoff, unsigned int len,
353 u_int8_t protocol, unsigned short family);
354int nf_route(struct net *net, struct dst_entry **dst, struct flowi *fl,
355 bool strict, unsigned short family);
356int nf_reroute(struct sk_buff *skb, struct nf_queue_entry *entry);
357
358#include <net/flow.h>
359
360struct nf_conn;
361enum nf_nat_manip_type;
362struct nlattr;
363enum ip_conntrack_dir;
364
365struct nf_nat_hook {
366 int (*parse_nat_setup)(struct nf_conn *ct, enum nf_nat_manip_type manip,
367 const struct nlattr *attr);
368 void (*decode_session)(struct sk_buff *skb, struct flowi *fl);
369 unsigned int (*manip_pkt)(struct sk_buff *skb, struct nf_conn *ct,
370 enum nf_nat_manip_type mtype,
371 enum ip_conntrack_dir dir);
372};
373
374extern struct nf_nat_hook __rcu *nf_nat_hook;
375
376static inline void
377nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family)
378{
379#if IS_ENABLED(CONFIG_NF_NAT)
380 struct nf_nat_hook *nat_hook;
381
382 rcu_read_lock();
383 nat_hook = rcu_dereference(nf_nat_hook);
384 if (nat_hook && nat_hook->decode_session)
385 nat_hook->decode_session(skb, fl);
386 rcu_read_unlock();
387#endif
388}
389
390#else
391static inline int
392NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
393 struct sk_buff *skb, struct net_device *in, struct net_device *out,
394 int (*okfn)(struct net *, struct sock *, struct sk_buff *),
395 bool cond)
396{
397 return okfn(net, sk, skb);
398}
399
400static inline int
401NF_HOOK(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
402 struct sk_buff *skb, struct net_device *in, struct net_device *out,
403 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
404{
405 return okfn(net, sk, skb);
406}
407
408static inline void
409NF_HOOK_LIST(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk,
410 struct list_head *head, struct net_device *in, struct net_device *out,
411 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
412{
413
414}
415
416static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net,
417 struct sock *sk, struct sk_buff *skb,
418 struct net_device *indev, struct net_device *outdev,
419 int (*okfn)(struct net *, struct sock *, struct sk_buff *))
420{
421 return 1;
422}
423struct flowi;
424static inline void
425nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family)
426{
427}
428#endif
429
430#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
431#include <linux/netfilter/nf_conntrack_zones_common.h>
432
433extern void (*ip_ct_attach)(struct sk_buff *, const struct sk_buff *) __rcu;
434void nf_ct_attach(struct sk_buff *, const struct sk_buff *);
435struct nf_conntrack_tuple;
436bool nf_ct_get_tuple_skb(struct nf_conntrack_tuple *dst_tuple,
437 const struct sk_buff *skb);
438#else
439static inline void nf_ct_attach(struct sk_buff *new, struct sk_buff *skb) {}
440struct nf_conntrack_tuple;
441static inline bool nf_ct_get_tuple_skb(struct nf_conntrack_tuple *dst_tuple,
442 const struct sk_buff *skb)
443{
444 return false;
445}
446#endif
447
448struct nf_conn;
449enum ip_conntrack_info;
450
451struct nf_ct_hook {
452 int (*update)(struct net *net, struct sk_buff *skb);
453 void (*destroy)(struct nf_conntrack *);
454 bool (*get_tuple_skb)(struct nf_conntrack_tuple *,
455 const struct sk_buff *);
456};
457extern struct nf_ct_hook __rcu *nf_ct_hook;
458
459struct nlattr;
460
461struct nfnl_ct_hook {
462 struct nf_conn *(*get_ct)(const struct sk_buff *skb,
463 enum ip_conntrack_info *ctinfo);
464 size_t (*build_size)(const struct nf_conn *ct);
465 int (*build)(struct sk_buff *skb, struct nf_conn *ct,
466 enum ip_conntrack_info ctinfo,
467 u_int16_t ct_attr, u_int16_t ct_info_attr);
468 int (*parse)(const struct nlattr *attr, struct nf_conn *ct);
469 int (*attach_expect)(const struct nlattr *attr, struct nf_conn *ct,
470 u32 portid, u32 report);
471 void (*seq_adjust)(struct sk_buff *skb, struct nf_conn *ct,
472 enum ip_conntrack_info ctinfo, s32 off);
473};
474extern struct nfnl_ct_hook __rcu *nfnl_ct_hook;
475
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482
483
484
485DECLARE_PER_CPU(bool, nf_skb_duplicated);
486
487#endif
488