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/in6.h>
21 #include <linux/ipv6.h>
22 #include <linux/skbuff.h>
23 #endif
24 #include <linux/types.h>
25 #include <linux/compiler.h>
26 #include <linux/netfilter_ipv6.h>
27
28 #include <linux/netfilter/x_tables.h>
29
30 #ifndef __KERNEL__
31 #define IP6T_FUNCTION_MAXNAMELEN XT_FUNCTION_MAXNAMELEN
32 #define IP6T_TABLE_MAXNAMELEN XT_TABLE_MAXNAMELEN
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 #define ip6t_entry_match xt_entry_match
38 #define ip6t_entry_target xt_entry_target
39 #define ip6t_standard_target xt_standard_target
40 #define ip6t_error_target xt_error_target
41 #define ip6t_counters xt_counters
42 #define IP6T_CONTINUE XT_CONTINUE
43 #define IP6T_RETURN XT_RETURN
44
45 /* Pre-iptables-1.4.0 */
46 #include <linux/netfilter/xt_tcpudp.h>
47 #define ip6t_tcp xt_tcp
48 #define ip6t_udp xt_udp
49 #define IP6T_TCP_INV_SRCPT XT_TCP_INV_SRCPT
50 #define IP6T_TCP_INV_DSTPT XT_TCP_INV_DSTPT
51 #define IP6T_TCP_INV_FLAGS XT_TCP_INV_FLAGS
52 #define IP6T_TCP_INV_OPTION XT_TCP_INV_OPTION
53 #define IP6T_TCP_INV_MASK XT_TCP_INV_MASK
54 #define IP6T_UDP_INV_SRCPT XT_UDP_INV_SRCPT
55 #define IP6T_UDP_INV_DSTPT XT_UDP_INV_DSTPT
56 #define IP6T_UDP_INV_MASK XT_UDP_INV_MASK
57
58 #define ip6t_counters_info xt_counters_info
59 #define IP6T_STANDARD_TARGET XT_STANDARD_TARGET
60 #define IP6T_ERROR_TARGET XT_ERROR_TARGET
61 #define IP6T_MATCH_ITERATE(e, fn, args...) \
62 XT_MATCH_ITERATE(struct ip6t_entry, e, fn, ## args)
63 #define IP6T_ENTRY_ITERATE(entries, size, fn, args...) \
64 XT_ENTRY_ITERATE(struct ip6t_entry, entries, size, fn, ## args)
65 #endif
66
67 /* Yes, Virginia, you have to zero the padding. */
68 struct ip6t_ip6 {
69 /* Source and destination IP6 addr */
70 struct in6_addr src, dst;
71 /* Mask for src and dest IP6 addr */
72 struct in6_addr smsk, dmsk;
73 char iniface[IFNAMSIZ], outiface[IFNAMSIZ];
74 unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ];
75
76 /* Upper protocol number
77 * - The allowed value is 0 (any) or protocol number of last parsable
78 * header, which is 50 (ESP), 59 (No Next Header), 135 (MH), or
79 * the non IPv6 extension headers.
80 * - The protocol numbers of IPv6 extension headers except of ESP and
81 * MH do not match any packets.
82 * - You also need to set IP6T_FLAGS_PROTO to "flags" to check protocol.
83 */
84 __u16 proto;
85 /* TOS to match iff flags & IP6T_F_TOS */
86 __u8 tos;
87
88 /* Flags word */
89 __u8 flags;
90 /* Inverse flags */
91 __u8 invflags;
92 };
93
94 /* Values for "flag" field in struct ip6t_ip6 (general ip6 structure). */
95 #define IP6T_F_PROTO 0x01 /* Set if rule cares about upper
96 protocols */
97 #define IP6T_F_TOS 0x02 /* Match the TOS. */
98 #define IP6T_F_GOTO 0x04 /* Set if jump is a goto */
99 #define IP6T_F_MASK 0x07 /* All possible flag bits mask. */
100
101 /* Values for "inv" field in struct ip6t_ip6. */
102 #define IP6T_INV_VIA_IN 0x01 /* Invert the sense of IN IFACE. */
103 #define IP6T_INV_VIA_OUT 0x02 /* Invert the sense of OUT IFACE */
104 #define IP6T_INV_TOS 0x04 /* Invert the sense of TOS. */
105 #define IP6T_INV_SRCIP 0x08 /* Invert the sense of SRC IP. */
106 #define IP6T_INV_DSTIP 0x10 /* Invert the sense of DST OP. */
107 #define IP6T_INV_FRAG 0x20 /* Invert the sense of FRAG. */
108 #define IP6T_INV_PROTO XT_INV_PROTO
109 #define IP6T_INV_MASK 0x7F /* All possible flag bits mask. */
110
111 /* This structure defines each of the firewall rules. Consists of 3
112 parts which are 1) general IP header stuff 2) match specific
113 stuff 3) the target to perform if the rule matches */
114 struct ip6t_entry {
115 struct ip6t_ip6 ipv6;
116
117 /* Mark with fields that we care about. */
118 unsigned int nfcache;
119
120 /* Size of ipt_entry + matches */
121 __u16 target_offset;
122 /* Size of ipt_entry + matches + target */
123 __u16 next_offset;
124
125 /* Back pointer */
126 unsigned int comefrom;
127
128 /* Packet and byte counters. */
129 struct xt_counters counters;
130
131 /* The matches (if any), then the target. */
132 unsigned char elems[0];
133 };
134
135 /* Standard entry */
136 struct ip6t_standard {
137 struct ip6t_entry entry;
138 struct xt_standard_target target;
139 };
140
141 struct ip6t_error {
142 struct ip6t_entry entry;
143 struct xt_error_target target;
144 };
145
146 #define IP6T_ENTRY_INIT(__size) \
147 { \
148 .target_offset = sizeof(struct ip6t_entry), \
149 .next_offset = (__size), \
150 }
151
152 #define IP6T_STANDARD_INIT(__verdict) \
153 { \
154 .entry = IP6T_ENTRY_INIT(sizeof(struct ip6t_standard)), \
155 .target = XT_TARGET_INIT(XT_STANDARD_TARGET, \
156 sizeof(struct xt_standard_target)), \
157 .target.verdict = -(__verdict) - 1, \
158 }
159
160 #define IP6T_ERROR_INIT \
161 { \
162 .entry = IP6T_ENTRY_INIT(sizeof(struct ip6t_error)), \
163 .target = XT_TARGET_INIT(XT_ERROR_TARGET, \
164 sizeof(struct xt_error_target)), \
165 .target.errorname = "ERROR", \
166 }
167
168 /*
169 * New IP firewall options for [gs]etsockopt at the RAW IP level.
170 * Unlike BSD Linux inherits IP options so you don't have to use
171 * a raw socket for this. Instead we check rights in the calls.
172 *
173 * ATTENTION: check linux/in6.h before adding new number here.
174 */
175 #define IP6T_BASE_CTL 64
176
177 #define IP6T_SO_SET_REPLACE (IP6T_BASE_CTL)
178 #define IP6T_SO_SET_ADD_COUNTERS (IP6T_BASE_CTL + 1)
179 #define IP6T_SO_SET_MAX IP6T_SO_SET_ADD_COUNTERS
180
181 #define IP6T_SO_GET_INFO (IP6T_BASE_CTL)
182 #define IP6T_SO_GET_ENTRIES (IP6T_BASE_CTL + 1)
183 #define IP6T_SO_GET_REVISION_MATCH (IP6T_BASE_CTL + 4)
184 #define IP6T_SO_GET_REVISION_TARGET (IP6T_BASE_CTL + 5)
185 #define IP6T_SO_GET_MAX IP6T_SO_GET_REVISION_TARGET
186
187 /* ICMP matching stuff */
188 struct ip6t_icmp {
189 __u8 type; /* type to match */
190 __u8 code[2]; /* range of code */
191 __u8 invflags; /* Inverse flags */
192 };
193
194 /* Values for "inv" field for struct ipt_icmp. */
195 #define IP6T_ICMP_INV 0x01 /* Invert the sense of type/code test */
196
197 /* The argument to IP6T_SO_GET_INFO */
198 struct ip6t_getinfo {
199 /* Which table: caller fills this in. */
200 char name[XT_TABLE_MAXNAMELEN];
201
202 /* Kernel fills these in. */
203 /* Which hook entry points are valid: bitmask */
204 unsigned int valid_hooks;
205
206 /* Hook entry points: one per netfilter hook. */
207 unsigned int hook_entry[NF_INET_NUMHOOKS];
208
209 /* Underflow points. */
210 unsigned int underflow[NF_INET_NUMHOOKS];
211
212 /* Number of entries */
213 unsigned int num_entries;
214
215 /* Size of entries. */
216 unsigned int size;
217 };
218
219 /* The argument to IP6T_SO_SET_REPLACE. */
220 struct ip6t_replace {
221 /* Which table. */
222 char name[XT_TABLE_MAXNAMELEN];
223
224 /* Which hook entry points are valid: bitmask. You can't
225 change this. */
226 unsigned int valid_hooks;
227
228 /* Number of entries */
229 unsigned int num_entries;
230
231 /* Total size of new entries */
232 unsigned int size;
233
234 /* Hook entry points. */
235 unsigned int hook_entry[NF_INET_NUMHOOKS];
236
237 /* Underflow points. */
238 unsigned int underflow[NF_INET_NUMHOOKS];
239
240 /* Information about old entries: */
241 /* Number of counters (must be equal to current number of entries). */
242 unsigned int num_counters;
243 /* The old entries' counters. */
244 struct xt_counters __user *counters;
245
246 /* The entries (hang off end: not really an array). */
247 struct ip6t_entry entries[0];
248 };
249
250 /* The argument to IP6T_SO_GET_ENTRIES. */
251 struct ip6t_get_entries {
252 /* Which table: user fills this in. */
253 char name[XT_TABLE_MAXNAMELEN];
254
255 /* User fills this in: total entry size. */
256 unsigned int size;
257
258 /* The entries. */
259 struct ip6t_entry entrytable[0];
260 };
261
262 /* Helper functions */
263 static __inline__ struct xt_entry_target *
ip6t_get_target(struct ip6t_entry * e)264 ip6t_get_target(struct ip6t_entry *e)
265 {
266 return (void *)e + e->target_offset;
267 }
268
269 /*
270 * Main firewall chains definitions and global var's definitions.
271 */
272
273 #ifdef __KERNEL__
274
275 #include <linux/init.h>
276 extern void ip6t_init(void) __init;
277
278 extern void *ip6t_alloc_initial_table(const struct xt_table *);
279 extern struct xt_table *ip6t_register_table(struct net *net,
280 const struct xt_table *table,
281 const struct ip6t_replace *repl);
282 extern void ip6t_unregister_table(struct net *net, struct xt_table *table);
283 extern unsigned int ip6t_do_table(struct sk_buff *skb,
284 unsigned int hook,
285 const struct net_device *in,
286 const struct net_device *out,
287 struct xt_table *table);
288
289 /* Check for an extension */
290 static inline int
ip6t_ext_hdr(u8 nexthdr)291 ip6t_ext_hdr(u8 nexthdr)
292 { return (nexthdr == IPPROTO_HOPOPTS) ||
293 (nexthdr == IPPROTO_ROUTING) ||
294 (nexthdr == IPPROTO_FRAGMENT) ||
295 (nexthdr == IPPROTO_ESP) ||
296 (nexthdr == IPPROTO_AH) ||
297 (nexthdr == IPPROTO_NONE) ||
298 (nexthdr == IPPROTO_DSTOPTS);
299 }
300
301 /* find specified header and get offset to it */
302 extern int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset,
303 int target, unsigned short *fragoff);
304
305 #ifdef CONFIG_COMPAT
306 #include <net/compat.h>
307
308 struct compat_ip6t_entry {
309 struct ip6t_ip6 ipv6;
310 compat_uint_t nfcache;
311 __u16 target_offset;
312 __u16 next_offset;
313 compat_uint_t comefrom;
314 struct compat_xt_counters counters;
315 unsigned char elems[0];
316 };
317
318 static inline struct xt_entry_target *
compat_ip6t_get_target(struct compat_ip6t_entry * e)319 compat_ip6t_get_target(struct compat_ip6t_entry *e)
320 {
321 return (void *)e + e->target_offset;
322 }
323
324 #endif /* CONFIG_COMPAT */
325 #endif /*__KERNEL__*/
326 #endif /* _IP6_TABLES_H */
327