Commit | Line | Data |
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1da177e4 LT |
1 | #ifndef __LINUX_NETFILTER_H |
2 | #define __LINUX_NETFILTER_H | |
3 | ||
4 | #ifdef __KERNEL__ | |
5 | #include <linux/init.h> | |
1da177e4 LT |
6 | #include <linux/skbuff.h> |
7 | #include <linux/net.h> | |
8 | #include <linux/if.h> | |
2e3075a2 JE |
9 | #include <linux/in.h> |
10 | #include <linux/in6.h> | |
1da177e4 LT |
11 | #include <linux/wait.h> |
12 | #include <linux/list.h> | |
13 | #endif | |
c8942f1f | 14 | #include <linux/types.h> |
1da177e4 LT |
15 | #include <linux/compiler.h> |
16 | ||
17 | /* Responses from hook functions. */ | |
18 | #define NF_DROP 0 | |
19 | #define NF_ACCEPT 1 | |
20 | #define NF_STOLEN 2 | |
21 | #define NF_QUEUE 3 | |
22 | #define NF_REPEAT 4 | |
23 | #define NF_STOP 5 | |
24 | #define NF_MAX_VERDICT NF_STOP | |
25 | ||
0ab43f84 HW |
26 | /* we overload the higher bits for encoding auxiliary data such as the queue |
27 | * number. Not nice, but better than additional function arguments. */ | |
28 | #define NF_VERDICT_MASK 0x0000ffff | |
29 | #define NF_VERDICT_BITS 16 | |
30 | ||
31 | #define NF_VERDICT_QMASK 0xffff0000 | |
32 | #define NF_VERDICT_QBITS 16 | |
33 | ||
fbabbed8 | 34 | #define NF_QUEUE_NR(x) ((((x) << NF_VERDICT_BITS) & NF_VERDICT_QMASK) | NF_QUEUE) |
0ab43f84 | 35 | |
6869c4d8 HW |
36 | /* only for userspace compatibility */ |
37 | #ifndef __KERNEL__ | |
1da177e4 LT |
38 | /* Generic cache responses from hook functions. |
39 | <= 0x2000 is used for protocol-flags. */ | |
40 | #define NFC_UNKNOWN 0x4000 | |
41 | #define NFC_ALTERED 0x8000 | |
6869c4d8 | 42 | #endif |
1da177e4 | 43 | |
6e23ae2a PM |
44 | enum nf_inet_hooks { |
45 | NF_INET_PRE_ROUTING, | |
46 | NF_INET_LOCAL_IN, | |
47 | NF_INET_FORWARD, | |
48 | NF_INET_LOCAL_OUT, | |
49 | NF_INET_POST_ROUTING, | |
50 | NF_INET_NUMHOOKS | |
51 | }; | |
52 | ||
7e9c6eeb JE |
53 | enum { |
54 | NFPROTO_UNSPEC = 0, | |
55 | NFPROTO_IPV4 = 2, | |
56 | NFPROTO_ARP = 3, | |
57 | NFPROTO_BRIDGE = 7, | |
58 | NFPROTO_IPV6 = 10, | |
59 | NFPROTO_DECNET = 12, | |
60 | NFPROTO_NUMPROTO, | |
61 | }; | |
62 | ||
643a2c15 | 63 | union nf_inet_addr { |
7b33ed22 | 64 | __u32 all[4]; |
643a2c15 JE |
65 | __be32 ip; |
66 | __be32 ip6[4]; | |
2e3075a2 JE |
67 | struct in_addr in; |
68 | struct in6_addr in6; | |
643a2c15 JE |
69 | }; |
70 | ||
1da177e4 | 71 | #ifdef __KERNEL__ |
1da177e4 LT |
72 | #ifdef CONFIG_NETFILTER |
73 | ||
b8beedd2 PM |
74 | static inline int nf_inet_addr_cmp(const union nf_inet_addr *a1, |
75 | const union nf_inet_addr *a2) | |
76 | { | |
77 | return a1->all[0] == a2->all[0] && | |
78 | a1->all[1] == a2->all[1] && | |
79 | a1->all[2] == a2->all[2] && | |
80 | a1->all[3] == a2->all[3]; | |
81 | } | |
82 | ||
1da177e4 LT |
83 | extern void netfilter_init(void); |
84 | ||
85 | /* Largest hook number + 1 */ | |
86 | #define NF_MAX_HOOKS 8 | |
87 | ||
88 | struct sk_buff; | |
1da177e4 LT |
89 | |
90 | typedef unsigned int nf_hookfn(unsigned int hooknum, | |
3db05fea | 91 | struct sk_buff *skb, |
1da177e4 LT |
92 | const struct net_device *in, |
93 | const struct net_device *out, | |
94 | int (*okfn)(struct sk_buff *)); | |
95 | ||
d94d9fee | 96 | struct nf_hook_ops { |
1da177e4 LT |
97 | struct list_head list; |
98 | ||
99 | /* User fills in from here down. */ | |
100 | nf_hookfn *hook; | |
101 | struct module *owner; | |
76108cea JE |
102 | u_int8_t pf; |
103 | unsigned int hooknum; | |
1da177e4 LT |
104 | /* Hooks are ordered in ascending priority. */ |
105 | int priority; | |
106 | }; | |
107 | ||
d94d9fee | 108 | struct nf_sockopt_ops { |
1da177e4 LT |
109 | struct list_head list; |
110 | ||
76108cea | 111 | u_int8_t pf; |
1da177e4 LT |
112 | |
113 | /* Non-inclusive ranges: use 0/0/NULL to never get called. */ | |
114 | int set_optmin; | |
115 | int set_optmax; | |
116 | int (*set)(struct sock *sk, int optval, void __user *user, unsigned int len); | |
3fdadf7d DM |
117 | int (*compat_set)(struct sock *sk, int optval, |
118 | void __user *user, unsigned int len); | |
1da177e4 LT |
119 | |
120 | int get_optmin; | |
121 | int get_optmax; | |
122 | int (*get)(struct sock *sk, int optval, void __user *user, int *len); | |
3fdadf7d DM |
123 | int (*compat_get)(struct sock *sk, int optval, |
124 | void __user *user, int *len); | |
1da177e4 | 125 | |
16fcec35 NH |
126 | /* Use the module struct to lock set/get code in place */ |
127 | struct module *owner; | |
1da177e4 LT |
128 | }; |
129 | ||
1da177e4 LT |
130 | /* Function to register/unregister hook points. */ |
131 | int nf_register_hook(struct nf_hook_ops *reg); | |
132 | void nf_unregister_hook(struct nf_hook_ops *reg); | |
972d1cb1 PM |
133 | int nf_register_hooks(struct nf_hook_ops *reg, unsigned int n); |
134 | void nf_unregister_hooks(struct nf_hook_ops *reg, unsigned int n); | |
1da177e4 LT |
135 | |
136 | /* Functions to register get/setsockopt ranges (non-inclusive). You | |
137 | need to check permissions yourself! */ | |
138 | int nf_register_sockopt(struct nf_sockopt_ops *reg); | |
139 | void nf_unregister_sockopt(struct nf_sockopt_ops *reg); | |
140 | ||
d62f9ed4 PM |
141 | #ifdef CONFIG_SYSCTL |
142 | /* Sysctl registration */ | |
b3fd3ffe PE |
143 | extern struct ctl_path nf_net_netfilter_sysctl_path[]; |
144 | extern struct ctl_path nf_net_ipv4_netfilter_sysctl_path[]; | |
d62f9ed4 PM |
145 | #endif /* CONFIG_SYSCTL */ |
146 | ||
7e9c6eeb | 147 | extern struct list_head nf_hooks[NFPROTO_NUMPROTO][NF_MAX_HOOKS]; |
1da177e4 | 148 | |
76108cea | 149 | int nf_hook_slow(u_int8_t pf, unsigned int hook, struct sk_buff *skb, |
16a6677f PM |
150 | struct net_device *indev, struct net_device *outdev, |
151 | int (*okfn)(struct sk_buff *), int thresh); | |
152 | ||
153 | /** | |
154 | * nf_hook_thresh - call a netfilter hook | |
155 | * | |
156 | * Returns 1 if the hook has allowed the packet to pass. The function | |
157 | * okfn must be invoked by the caller in this case. Any other return | |
158 | * value indicates the packet has been consumed by the hook. | |
159 | */ | |
76108cea | 160 | static inline int nf_hook_thresh(u_int8_t pf, unsigned int hook, |
3db05fea | 161 | struct sk_buff *skb, |
16a6677f PM |
162 | struct net_device *indev, |
163 | struct net_device *outdev, | |
48d5cad8 PM |
164 | int (*okfn)(struct sk_buff *), int thresh, |
165 | int cond) | |
16a6677f | 166 | { |
48d5cad8 PM |
167 | if (!cond) |
168 | return 1; | |
16a6677f PM |
169 | #ifndef CONFIG_NETFILTER_DEBUG |
170 | if (list_empty(&nf_hooks[pf][hook])) | |
171 | return 1; | |
172 | #endif | |
3db05fea | 173 | return nf_hook_slow(pf, hook, skb, indev, outdev, okfn, thresh); |
16a6677f PM |
174 | } |
175 | ||
76108cea | 176 | static inline int nf_hook(u_int8_t pf, unsigned int hook, struct sk_buff *skb, |
16a6677f PM |
177 | struct net_device *indev, struct net_device *outdev, |
178 | int (*okfn)(struct sk_buff *)) | |
179 | { | |
3db05fea | 180 | return nf_hook_thresh(pf, hook, skb, indev, outdev, okfn, INT_MIN, 1); |
16a6677f | 181 | } |
1da177e4 LT |
182 | |
183 | /* Activate hook; either okfn or kfree_skb called, unless a hook | |
184 | returns NF_STOLEN (in which case, it's up to the hook to deal with | |
185 | the consequences). | |
186 | ||
187 | Returns -ERRNO if packet dropped. Zero means queued, stolen or | |
188 | accepted. | |
189 | */ | |
190 | ||
191 | /* RR: | |
192 | > I don't want nf_hook to return anything because people might forget | |
193 | > about async and trust the return value to mean "packet was ok". | |
194 | ||
195 | AK: | |
196 | Just document it clearly, then you can expect some sense from kernel | |
197 | coders :) | |
198 | */ | |
199 | ||
200 | /* This is gross, but inline doesn't cut it for avoiding the function | |
201 | call in fast path: gcc doesn't inline (needs value tracking?). --RR */ | |
16a6677f PM |
202 | |
203 | /* HX: It's slightly less gross now. */ | |
204 | ||
1da177e4 LT |
205 | #define NF_HOOK_THRESH(pf, hook, skb, indev, outdev, okfn, thresh) \ |
206 | ({int __ret; \ | |
3db05fea | 207 | if ((__ret=nf_hook_thresh(pf, hook, (skb), indev, outdev, okfn, thresh, 1)) == 1)\ |
48d5cad8 PM |
208 | __ret = (okfn)(skb); \ |
209 | __ret;}) | |
210 | ||
211 | #define NF_HOOK_COND(pf, hook, skb, indev, outdev, okfn, cond) \ | |
212 | ({int __ret; \ | |
3db05fea | 213 | if ((__ret=nf_hook_thresh(pf, hook, (skb), indev, outdev, okfn, INT_MIN, cond)) == 1)\ |
1da177e4 LT |
214 | __ret = (okfn)(skb); \ |
215 | __ret;}) | |
1da177e4 | 216 | |
16a6677f PM |
217 | #define NF_HOOK(pf, hook, skb, indev, outdev, okfn) \ |
218 | NF_HOOK_THRESH(pf, hook, skb, indev, outdev, okfn, INT_MIN) | |
1da177e4 LT |
219 | |
220 | /* Call setsockopt() */ | |
76108cea | 221 | int nf_setsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt, |
b7058842 | 222 | unsigned int len); |
76108cea | 223 | int nf_getsockopt(struct sock *sk, u_int8_t pf, int optval, char __user *opt, |
1da177e4 LT |
224 | int *len); |
225 | ||
76108cea | 226 | int compat_nf_setsockopt(struct sock *sk, u_int8_t pf, int optval, |
b7058842 | 227 | char __user *opt, unsigned int len); |
76108cea | 228 | int compat_nf_getsockopt(struct sock *sk, u_int8_t pf, int optval, |
3fdadf7d DM |
229 | char __user *opt, int *len); |
230 | ||
089af26c HW |
231 | /* Call this before modifying an existing packet: ensures it is |
232 | modifiable and linear to the point you care about (writable_len). | |
233 | Returns true or false. */ | |
37d41879 | 234 | extern int skb_make_writable(struct sk_buff *skb, unsigned int writable_len); |
089af26c | 235 | |
1841a4c7 | 236 | struct flowi; |
02f014d8 | 237 | struct nf_queue_entry; |
c01cd429 | 238 | |
bce8032e PM |
239 | struct nf_afinfo { |
240 | unsigned short family; | |
b51655b9 | 241 | __sum16 (*checksum)(struct sk_buff *skb, unsigned int hook, |
422c346f | 242 | unsigned int dataoff, u_int8_t protocol); |
d63a6507 PM |
243 | __sum16 (*checksum_partial)(struct sk_buff *skb, |
244 | unsigned int hook, | |
245 | unsigned int dataoff, | |
246 | unsigned int len, | |
247 | u_int8_t protocol); | |
1841a4c7 | 248 | int (*route)(struct dst_entry **dst, struct flowi *fl); |
bce8032e | 249 | void (*saveroute)(const struct sk_buff *skb, |
02f014d8 | 250 | struct nf_queue_entry *entry); |
3db05fea | 251 | int (*reroute)(struct sk_buff *skb, |
02f014d8 | 252 | const struct nf_queue_entry *entry); |
bce8032e | 253 | int route_key_size; |
2cc7d573 HW |
254 | }; |
255 | ||
7e9c6eeb | 256 | extern const struct nf_afinfo *nf_afinfo[NFPROTO_NUMPROTO]; |
1e796fda | 257 | static inline const struct nf_afinfo *nf_get_afinfo(unsigned short family) |
bce8032e PM |
258 | { |
259 | return rcu_dereference(nf_afinfo[family]); | |
260 | } | |
2cc7d573 | 261 | |
b51655b9 | 262 | static inline __sum16 |
422c346f PM |
263 | nf_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff, |
264 | u_int8_t protocol, unsigned short family) | |
265 | { | |
1e796fda | 266 | const struct nf_afinfo *afinfo; |
b51655b9 | 267 | __sum16 csum = 0; |
422c346f PM |
268 | |
269 | rcu_read_lock(); | |
270 | afinfo = nf_get_afinfo(family); | |
271 | if (afinfo) | |
272 | csum = afinfo->checksum(skb, hook, dataoff, protocol); | |
273 | rcu_read_unlock(); | |
274 | return csum; | |
275 | } | |
276 | ||
d63a6507 PM |
277 | static inline __sum16 |
278 | nf_checksum_partial(struct sk_buff *skb, unsigned int hook, | |
279 | unsigned int dataoff, unsigned int len, | |
280 | u_int8_t protocol, unsigned short family) | |
281 | { | |
282 | const struct nf_afinfo *afinfo; | |
283 | __sum16 csum = 0; | |
284 | ||
285 | rcu_read_lock(); | |
286 | afinfo = nf_get_afinfo(family); | |
287 | if (afinfo) | |
288 | csum = afinfo->checksum_partial(skb, hook, dataoff, len, | |
289 | protocol); | |
290 | rcu_read_unlock(); | |
291 | return csum; | |
292 | } | |
293 | ||
1e796fda PM |
294 | extern int nf_register_afinfo(const struct nf_afinfo *afinfo); |
295 | extern void nf_unregister_afinfo(const struct nf_afinfo *afinfo); | |
bce8032e | 296 | |
eb9c7ebe PM |
297 | #include <net/flow.h> |
298 | extern void (*ip_nat_decode_session)(struct sk_buff *, struct flowi *); | |
299 | ||
300 | static inline void | |
76108cea | 301 | nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family) |
eb9c7ebe | 302 | { |
051578cc | 303 | #ifdef CONFIG_NF_NAT_NEEDED |
eb9c7ebe PM |
304 | void (*decodefn)(struct sk_buff *, struct flowi *); |
305 | ||
051578cc PM |
306 | if (family == AF_INET) { |
307 | rcu_read_lock(); | |
308 | decodefn = rcu_dereference(ip_nat_decode_session); | |
309 | if (decodefn) | |
310 | decodefn(skb, fl); | |
311 | rcu_read_unlock(); | |
312 | } | |
eb9c7ebe PM |
313 | #endif |
314 | } | |
315 | ||
608c8e4f HW |
316 | #ifdef CONFIG_PROC_FS |
317 | #include <linux/proc_fs.h> | |
318 | extern struct proc_dir_entry *proc_net_netfilter; | |
319 | #endif | |
320 | ||
1da177e4 LT |
321 | #else /* !CONFIG_NETFILTER */ |
322 | #define NF_HOOK(pf, hook, skb, indev, outdev, okfn) (okfn)(skb) | |
48d5cad8 | 323 | #define NF_HOOK_COND(pf, hook, skb, indev, outdev, okfn, cond) (okfn)(skb) |
76108cea | 324 | static inline int nf_hook_thresh(u_int8_t pf, unsigned int hook, |
3db05fea | 325 | struct sk_buff *skb, |
f53b61d8 DM |
326 | struct net_device *indev, |
327 | struct net_device *outdev, | |
48d5cad8 PM |
328 | int (*okfn)(struct sk_buff *), int thresh, |
329 | int cond) | |
f53b61d8 | 330 | { |
3db05fea | 331 | return okfn(skb); |
f53b61d8 | 332 | } |
76108cea | 333 | static inline int nf_hook(u_int8_t pf, unsigned int hook, struct sk_buff *skb, |
f53b61d8 DM |
334 | struct net_device *indev, struct net_device *outdev, |
335 | int (*okfn)(struct sk_buff *)) | |
336 | { | |
9c92d348 | 337 | return 1; |
f53b61d8 | 338 | } |
f53b61d8 | 339 | struct flowi; |
eb9c7ebe | 340 | static inline void |
76108cea JE |
341 | nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family) |
342 | { | |
343 | } | |
1da177e4 LT |
344 | #endif /*CONFIG_NETFILTER*/ |
345 | ||
5f79e0f9 YK |
346 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
347 | extern void (*ip_ct_attach)(struct sk_buff *, struct sk_buff *); | |
348 | extern void nf_ct_attach(struct sk_buff *, struct sk_buff *); | |
de6e05c4 | 349 | extern void (*nf_ct_destroy)(struct nf_conntrack *); |
5f79e0f9 YK |
350 | #else |
351 | static inline void nf_ct_attach(struct sk_buff *new, struct sk_buff *skb) {} | |
352 | #endif | |
353 | ||
1da177e4 LT |
354 | #endif /*__KERNEL__*/ |
355 | #endif /*__LINUX_NETFILTER_H*/ |