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 * 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