1 /*
2 * 25-Jul-1998 Major changes to allow for ip chain table
3 *
4 * 3-Jan-2000 Named tables to allow packet selection for different uses.
5 */
6
7 /*
8 * Format of an IP6 firewall descriptor
9 *
10 * src, dst, src_mask, dst_mask are always stored in network byte order.
11 * flags are stored in host byte order (of course).
12 * Port numbers are stored in HOST byte order.
13 */
14
15 #ifndef _IP6_TABLES_H
16 #define _IP6_TABLES_H
17
18 #ifdef __KERNEL__
19 #include <linux/if.h>
20 #include <linux/types.h>
21 #include <linux/in6.h>
22 #include <linux/ipv6.h>
23 #include <linux/skbuff.h>
24 #endif
25 #include <linux/compiler.h>
26 #include <linux/netfilter_ipv6.h>
27
28 #include <linux/netfilter/x_tables.h>
29
30 #define IP6T_FUNCTION_MAXNAMELEN XT_FUNCTION_MAXNAMELEN
31 #define IP6T_TABLE_MAXNAMELEN XT_TABLE_MAXNAMELEN
32
33 #define ip6t_match xt_match
34 #define ip6t_target xt_target
35 #define ip6t_table xt_table
36 #define ip6t_get_revision xt_get_revision
37
38 /* Yes, Virginia, you have to zero the padding. */
39 struct ip6t_ip6 {
40 /* Source and destination IP6 addr */
41 struct in6_addr src, dst;
42 /* Mask for src and dest IP6 addr */
43 struct in6_addr smsk, dmsk;
44 char iniface[IFNAMSIZ], outiface[IFNAMSIZ];
45 unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ];
46
47 /* ARGH, HopByHop uses 0, so can't do 0 = ANY,
48 instead IP6T_F_NOPROTO must be set */
49 u_int16_t proto;
50 /* TOS to match iff flags & IP6T_F_TOS */
51 u_int8_t tos;
52
53 /* Flags word */
54 u_int8_t flags;
55 /* Inverse flags */
56 u_int8_t invflags;
57 };
58
59 #define ip6t_entry_match xt_entry_match
60 #define ip6t_entry_target xt_entry_target
61 #define ip6t_standard_target xt_standard_target
62
63 #define ip6t_counters xt_counters
64
65 /* Values for "flag" field in struct ip6t_ip6 (general ip6 structure). */
66 #define IP6T_F_PROTO 0x01 /* Set if rule cares about upper
67 protocols */
68 #define IP6T_F_TOS 0x02 /* Match the TOS. */
69 #define IP6T_F_GOTO 0x04 /* Set if jump is a goto */
70 #define IP6T_F_MASK 0x07 /* All possible flag bits mask. */
71
72 /* Values for "inv" field in struct ip6t_ip6. */
73 #define IP6T_INV_VIA_IN 0x01 /* Invert the sense of IN IFACE. */
74 #define IP6T_INV_VIA_OUT 0x02 /* Invert the sense of OUT IFACE */
75 #define IP6T_INV_TOS 0x04 /* Invert the sense of TOS. */
76 #define IP6T_INV_SRCIP 0x08 /* Invert the sense of SRC IP. */
77 #define IP6T_INV_DSTIP 0x10 /* Invert the sense of DST OP. */
78 #define IP6T_INV_FRAG 0x20 /* Invert the sense of FRAG. */
79 #define IP6T_INV_PROTO XT_INV_PROTO
80 #define IP6T_INV_MASK 0x7F /* All possible flag bits mask. */
81
82 /* This structure defines each of the firewall rules. Consists of 3
83 parts which are 1) general IP header stuff 2) match specific
84 stuff 3) the target to perform if the rule matches */
85 struct ip6t_entry
86 {
87 struct ip6t_ip6 ipv6;
88
89 /* Mark with fields that we care about. */
90 unsigned int nfcache;
91
92 /* Size of ipt_entry + matches */
93 u_int16_t target_offset;
94 /* Size of ipt_entry + matches + target */
95 u_int16_t next_offset;
96
97 /* Back pointer */
98 unsigned int comefrom;
99
100 /* Packet and byte counters. */
101 struct xt_counters counters;
102
103 /* The matches (if any), then the target. */
104 unsigned char elems[0];
105 };
106
107 /*
108 * New IP firewall options for [gs]etsockopt at the RAW IP level.
109 * Unlike BSD Linux inherits IP options so you don't have to use
110 * a raw socket for this. Instead we check rights in the calls. */
111 #define IP6T_BASE_CTL XT_BASE_CTL
112
113 #define IP6T_SO_SET_REPLACE XT_SO_SET_REPLACE
114 #define IP6T_SO_SET_ADD_COUNTERS XT_SO_SET_ADD_COUNTERS
115 #define IP6T_SO_SET_MAX XT_SO_SET_MAX
116
117 #define IP6T_SO_GET_INFO XT_SO_GET_INFO
118 #define IP6T_SO_GET_ENTRIES XT_SO_GET_ENTRIES
119 #define IP6T_SO_GET_REVISION_MATCH XT_SO_GET_REVISION_MATCH
120 #define IP6T_SO_GET_REVISION_TARGET XT_SO_GET_REVISION_TARGET
121 #define IP6T_SO_GET_MAX XT_SO_GET_REVISION_TARGET
122
123 /* CONTINUE verdict for targets */
124 #define IP6T_CONTINUE XT_CONTINUE
125
126 /* For standard target */
127 #define IP6T_RETURN XT_RETURN
128
129 /* TCP/UDP matching stuff */
130 #include <linux/netfilter/xt_tcpudp.h>
131
132 #define ip6t_tcp xt_tcp
133 #define ip6t_udp xt_udp
134
135 /* Values for "inv" field in struct ipt_tcp. */
136 #define IP6T_TCP_INV_SRCPT XT_TCP_INV_SRCPT
137 #define IP6T_TCP_INV_DSTPT XT_TCP_INV_DSTPT
138 #define IP6T_TCP_INV_FLAGS XT_TCP_INV_FLAGS
139 #define IP6T_TCP_INV_OPTION XT_TCP_INV_OPTION
140 #define IP6T_TCP_INV_MASK XT_TCP_INV_MASK
141
142 /* Values for "invflags" field in struct ipt_udp. */
143 #define IP6T_UDP_INV_SRCPT XT_UDP_INV_SRCPT
144 #define IP6T_UDP_INV_DSTPT XT_UDP_INV_DSTPT
145 #define IP6T_UDP_INV_MASK XT_UDP_INV_MASK
146
147 /* ICMP matching stuff */
148 struct ip6t_icmp
149 {
150 u_int8_t type; /* type to match */
151 u_int8_t code[2]; /* range of code */
152 u_int8_t invflags; /* Inverse flags */
153 };
154
155 /* Values for "inv" field for struct ipt_icmp. */
156 #define IP6T_ICMP_INV 0x01 /* Invert the sense of type/code test */
157
158 /* The argument to IP6T_SO_GET_INFO */
159 struct ip6t_getinfo
160 {
161 /* Which table: caller fills this in. */
162 char name[IP6T_TABLE_MAXNAMELEN];
163
164 /* Kernel fills these in. */
165 /* Which hook entry points are valid: bitmask */
166 unsigned int valid_hooks;
167
168 /* Hook entry points: one per netfilter hook. */
169 unsigned int hook_entry[NF_IP6_NUMHOOKS];
170
171 /* Underflow points. */
172 unsigned int underflow[NF_IP6_NUMHOOKS];
173
174 /* Number of entries */
175 unsigned int num_entries;
176
177 /* Size of entries. */
178 unsigned int size;
179 };
180
181 /* The argument to IP6T_SO_SET_REPLACE. */
182 struct ip6t_replace
183 {
184 /* Which table. */
185 char name[IP6T_TABLE_MAXNAMELEN];
186
187 /* Which hook entry points are valid: bitmask. You can't
188 change this. */
189 unsigned int valid_hooks;
190
191 /* Number of entries */
192 unsigned int num_entries;
193
194 /* Total size of new entries */
195 unsigned int size;
196
197 /* Hook entry points. */
198 unsigned int hook_entry[NF_IP6_NUMHOOKS];
199
200 /* Underflow points. */
201 unsigned int underflow[NF_IP6_NUMHOOKS];
202
203 /* Information about old entries: */
204 /* Number of counters (must be equal to current number of entries). */
205 unsigned int num_counters;
206 /* The old entries' counters. */
207 struct xt_counters __user *counters;
208
209 /* The entries (hang off end: not really an array). */
210 struct ip6t_entry entries[0];
211 };
212
213 /* The argument to IP6T_SO_ADD_COUNTERS. */
214 #define ip6t_counters_info xt_counters_info
215
216 /* The argument to IP6T_SO_GET_ENTRIES. */
217 struct ip6t_get_entries
218 {
219 /* Which table: user fills this in. */
220 char name[IP6T_TABLE_MAXNAMELEN];
221
222 /* User fills this in: total entry size. */
223 unsigned int size;
224
225 /* The entries. */
226 struct ip6t_entry entrytable[0];
227 };
228
229 /* Standard return verdict, or do jump. */
230 #define IP6T_STANDARD_TARGET XT_STANDARD_TARGET
231 /* Error verdict. */
232 #define IP6T_ERROR_TARGET XT_ERROR_TARGET
233
234 /* Helper functions */
235 static __inline__ struct ip6t_entry_target *
ip6t_get_target(struct ip6t_entry * e)236 ip6t_get_target(struct ip6t_entry *e)
237 {
238 return (void *)e + e->target_offset;
239 }
240
241 /* fn returns 0 to continue iteration */
242 #define IP6T_MATCH_ITERATE(e, fn, args...) \
243 ({ \
244 unsigned int __i; \
245 int __ret = 0; \
246 struct ip6t_entry_match *__m; \
247 \
248 for (__i = sizeof(struct ip6t_entry); \
249 __i < (e)->target_offset; \
250 __i += __m->u.match_size) { \
251 __m = (void *)(e) + __i; \
252 \
253 __ret = fn(__m , ## args); \
254 if (__ret != 0) \
255 break; \
256 } \
257 __ret; \
258 })
259
260 /* fn returns 0 to continue iteration */
261 #define IP6T_ENTRY_ITERATE(entries, size, fn, args...) \
262 ({ \
263 unsigned int __i; \
264 int __ret = 0; \
265 struct ip6t_entry *__e; \
266 \
267 for (__i = 0; __i < (size); __i += __e->next_offset) { \
268 __e = (void *)(entries) + __i; \
269 \
270 __ret = fn(__e , ## args); \
271 if (__ret != 0) \
272 break; \
273 } \
274 __ret; \
275 })
276
277 /*
278 * Main firewall chains definitions and global var's definitions.
279 */
280
281 #ifdef __KERNEL__
282
283 #include <linux/init.h>
284 extern void ip6t_init(void) __init;
285
286 #define ip6t_register_target(tgt) \
287 ({ (tgt)->family = AF_INET6; \
288 xt_register_target(tgt); })
289 #define ip6t_unregister_target(tgt) xt_unregister_target(tgt)
290
291 #define ip6t_register_match(match) \
292 ({ (match)->family = AF_INET6; \
293 xt_register_match(match); })
294 #define ip6t_unregister_match(match) xt_unregister_match(match)
295
296 extern int ip6t_register_table(struct ip6t_table *table,
297 const struct ip6t_replace *repl);
298 extern void ip6t_unregister_table(struct ip6t_table *table);
299 extern unsigned int ip6t_do_table(struct sk_buff **pskb,
300 unsigned int hook,
301 const struct net_device *in,
302 const struct net_device *out,
303 struct ip6t_table *table,
304 void *userdata);
305
306 /* Check for an extension */
307 extern int ip6t_ext_hdr(u8 nexthdr);
308 /* find specified header and get offset to it */
309 extern int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset,
310 int target, unsigned short *fragoff);
311
312 extern int ip6_masked_addrcmp(const struct in6_addr *addr1,
313 const struct in6_addr *mask,
314 const struct in6_addr *addr2);
315
316 #define IP6T_ALIGN(s) (((s) + (__alignof__(struct ip6t_entry)-1)) & ~(__alignof__(struct ip6t_entry)-1))
317
318 #endif /*__KERNEL__*/
319 #endif /* _IP6_TABLES_H */
320