include/linux/netfilter_ipv6/ip6_tables.h

   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  *
 112  * ATTENTION: check linux/in6.h before adding new number here.
 113  */
 114 #define IP6T_BASE_CTL                   64
 115
 116 #define IP6T_SO_SET_REPLACE             (IP6T_BASE_CTL)
 117 #define IP6T_SO_SET_ADD_COUNTERS        (IP6T_BASE_CTL + 1)
 118 #define IP6T_SO_SET_MAX                 IP6T_SO_SET_ADD_COUNTERS
 119
 120 #define IP6T_SO_GET_INFO                (IP6T_BASE_CTL)
 121 #define IP6T_SO_GET_ENTRIES             (IP6T_BASE_CTL + 1)
 122 #define IP6T_SO_GET_REVISION_MATCH      (IP6T_BASE_CTL + 4)
 123 #define IP6T_SO_GET_REVISION_TARGET     (IP6T_BASE_CTL + 5)
 124 #define IP6T_SO_GET_MAX                 IP6T_SO_GET_REVISION_TARGET
 125
 126 /* CONTINUE verdict for targets */
 127 #define IP6T_CONTINUE XT_CONTINUE
 128
 129 /* For standard target */
 130 #define IP6T_RETURN XT_RETURN
 131
 132 /* TCP/UDP matching stuff */
 133 #include <linux/netfilter/xt_tcpudp.h>
 134
 135 #define ip6t_tcp xt_tcp
 136 #define ip6t_udp xt_udp
 137
 138 /* Values for "inv" field in struct ipt_tcp. */
 139 #define IP6T_TCP_INV_SRCPT      XT_TCP_INV_SRCPT
 140 #define IP6T_TCP_INV_DSTPT      XT_TCP_INV_DSTPT
 141 #define IP6T_TCP_INV_FLAGS      XT_TCP_INV_FLAGS
 142 #define IP6T_TCP_INV_OPTION     XT_TCP_INV_OPTION
 143 #define IP6T_TCP_INV_MASK       XT_TCP_INV_MASK
 144
 145 /* Values for "invflags" field in struct ipt_udp. */
 146 #define IP6T_UDP_INV_SRCPT      XT_UDP_INV_SRCPT
 147 #define IP6T_UDP_INV_DSTPT      XT_UDP_INV_DSTPT
 148 #define IP6T_UDP_INV_MASK       XT_UDP_INV_MASK
 149
 150 /* ICMP matching stuff */
 151 struct ip6t_icmp
 152 {
 153         u_int8_t type;                          /* type to match */
 154         u_int8_t code[2];                       /* range of code */
 155         u_int8_t invflags;                      /* Inverse flags */
 156 };
 157
 158 /* Values for "inv" field for struct ipt_icmp. */
 159 #define IP6T_ICMP_INV   0x01    /* Invert the sense of type/code test */
 160
 161 /* The argument to IP6T_SO_GET_INFO */
 162 struct ip6t_getinfo
 163 {
 164         /* Which table: caller fills this in. */
 165         char name[IP6T_TABLE_MAXNAMELEN];
 166
 167         /* Kernel fills these in. */
 168         /* Which hook entry points are valid: bitmask */
 169         unsigned int valid_hooks;
 170
 171         /* Hook entry points: one per netfilter hook. */
 172         unsigned int hook_entry[NF_IP6_NUMHOOKS];
 173
 174         /* Underflow points. */
 175         unsigned int underflow[NF_IP6_NUMHOOKS];
 176
 177         /* Number of entries */
 178         unsigned int num_entries;
 179
 180         /* Size of entries. */
 181         unsigned int size;
 182 };
 183
 184 /* The argument to IP6T_SO_SET_REPLACE. */
 185 struct ip6t_replace
 186 {
 187         /* Which table. */
 188         char name[IP6T_TABLE_MAXNAMELEN];
 189
 190         /* Which hook entry points are valid: bitmask.  You can't
 191            change this. */
 192         unsigned int valid_hooks;
 193
 194         /* Number of entries */
 195         unsigned int num_entries;
 196
 197         /* Total size of new entries */
 198         unsigned int size;
 199
 200         /* Hook entry points. */
 201         unsigned int hook_entry[NF_IP6_NUMHOOKS];
 202
 203         /* Underflow points. */
 204         unsigned int underflow[NF_IP6_NUMHOOKS];
 205
 206         /* Information about old entries: */
 207         /* Number of counters (must be equal to current number of entries). */
 208         unsigned int num_counters;
 209         /* The old entries' counters. */
 210         struct xt_counters __user *counters;
 211
 212         /* The entries (hang off end: not really an array). */
 213         struct ip6t_entry entries[0];
 214 };
 215
 216 /* The argument to IP6T_SO_ADD_COUNTERS. */
 217 #define ip6t_counters_info xt_counters_info
 218
 219 /* The argument to IP6T_SO_GET_ENTRIES. */
 220 struct ip6t_get_entries
 221 {
 222         /* Which table: user fills this in. */
 223         char name[IP6T_TABLE_MAXNAMELEN];
 224
 225         /* User fills this in: total entry size. */
 226         unsigned int size;
 227
 228         /* The entries. */
 229         struct ip6t_entry entrytable[0];
 230 };
 231
 232 /* Standard return verdict, or do jump. */
 233 #define IP6T_STANDARD_TARGET XT_STANDARD_TARGET
 234 /* Error verdict. */
 235 #define IP6T_ERROR_TARGET XT_ERROR_TARGET
 236
 237 /* Helper functions */
 238 static __inline__ struct ip6t_entry_target *
 239 ip6t_get_target(struct ip6t_entry *e)
 240 {
 241         return (void *)e + e->target_offset;
 242 }
 243
 244 /* fn returns 0 to continue iteration */
 245 #define IP6T_MATCH_ITERATE(e, fn, args...)      \
 246 ({                                              \
 247         unsigned int __i;                       \
 248         int __ret = 0;                          \
 249         struct ip6t_entry_match *__m;           \
 250                                                 \
 251         for (__i = sizeof(struct ip6t_entry);   \
 252              __i < (e)->target_offset;          \
 253              __i += __m->u.match_size) {        \
 254                 __m = (void *)(e) + __i;        \
 255                                                 \
 256                 __ret = fn(__m , ## args);      \
 257                 if (__ret != 0)                 \
 258                         break;                  \
 259         }                                       \
 260         __ret;                                  \
 261 })
 262
 263 /* fn returns 0 to continue iteration */
 264 #define IP6T_ENTRY_ITERATE(entries, size, fn, args...)          \
 265 ({                                                              \
 266         unsigned int __i;                                       \
 267         int __ret = 0;                                          \
 268         struct ip6t_entry *__e;                                 \
 269                                                                 \
 270         for (__i = 0; __i < (size); __i += __e->next_offset) {  \
 271                 __e = (void *)(entries) + __i;                  \
 272                                                                 \
 273                 __ret = fn(__e , ## args);                      \
 274                 if (__ret != 0)                                 \
 275                         break;                                  \
 276         }                                                       \
 277         __ret;                                                  \
 278 })
 279
 280 /*
 281  *      Main firewall chains definitions and global var's definitions.
 282  */
 283
 284 #ifdef __KERNEL__
 285
 286 #include <linux/init.h>
 287 extern void ip6t_init(void) __init;
 288
 289 #define ip6t_register_target(tgt)               \
 290 ({      (tgt)->family = AF_INET6;               \
 291         xt_register_target(tgt); })
 292 #define ip6t_unregister_target(tgt) xt_unregister_target(tgt)
 293
 294 #define ip6t_register_match(match)              \
 295 ({      (match)->family = AF_INET6;             \
 296         xt_register_match(match); })
 297 #define ip6t_unregister_match(match) xt_unregister_match(match)
 298
 299 extern int ip6t_register_table(struct ip6t_table *table,
 300                                const struct ip6t_replace *repl);
 301 extern void ip6t_unregister_table(struct ip6t_table *table);
 302 extern unsigned int ip6t_do_table(struct sk_buff **pskb,
 303                                   unsigned int hook,
 304                                   const struct net_device *in,
 305                                   const struct net_device *out,
 306                                   struct ip6t_table *table);
 307
 308 /* Check for an extension */
 309 extern int ip6t_ext_hdr(u8 nexthdr);
 310 /* find specified header and get offset to it */
 311 extern int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset,
 312                          int target, unsigned short *fragoff);
 313
 314 extern int ip6_masked_addrcmp(const struct in6_addr *addr1,
 315                               const struct in6_addr *mask,
 316                               const struct in6_addr *addr2);
 317
 318 #define IP6T_ALIGN(s) (((s) + (__alignof__(struct ip6t_entry)-1)) & ~(__alignof__(struct ip6t_entry)-1))
 319
 320 #endif /*__KERNEL__*/
 321 #endif /* _IP6_TABLES_H */