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 /* Standard entry */
 108 struct ip6t_standard
 109 {
 110         struct ip6t_entry entry;
 111         struct ip6t_standard_target target;
 112 };
 113
 114 struct ip6t_error_target
 115 {
 116         struct ip6t_entry_target target;
 117         char errorname[IP6T_FUNCTION_MAXNAMELEN];
 118 };
 119
 120 struct ip6t_error
 121 {
 122         struct ip6t_entry entry;
 123         struct ip6t_error_target target;
 124 };
 125
 126 /*
 127  * New IP firewall options for [gs]etsockopt at the RAW IP level.
 128  * Unlike BSD Linux inherits IP options so you don't have to use
 129  * a raw socket for this. Instead we check rights in the calls.
 130  *
 131  * ATTENTION: check linux/in6.h before adding new number here.
 132  */
 133 #define IP6T_BASE_CTL                   64
 134
 135 #define IP6T_SO_SET_REPLACE             (IP6T_BASE_CTL)
 136 #define IP6T_SO_SET_ADD_COUNTERS        (IP6T_BASE_CTL + 1)
 137 #define IP6T_SO_SET_MAX                 IP6T_SO_SET_ADD_COUNTERS
 138
 139 #define IP6T_SO_GET_INFO                (IP6T_BASE_CTL)
 140 #define IP6T_SO_GET_ENTRIES             (IP6T_BASE_CTL + 1)
 141 #define IP6T_SO_GET_REVISION_MATCH      (IP6T_BASE_CTL + 4)
 142 #define IP6T_SO_GET_REVISION_TARGET     (IP6T_BASE_CTL + 5)
 143 #define IP6T_SO_GET_MAX                 IP6T_SO_GET_REVISION_TARGET
 144
 145 /* CONTINUE verdict for targets */
 146 #define IP6T_CONTINUE XT_CONTINUE
 147
 148 /* For standard target */
 149 #define IP6T_RETURN XT_RETURN
 150
 151 /* TCP/UDP matching stuff */
 152 #include <linux/netfilter/xt_tcpudp.h>
 153
 154 #define ip6t_tcp xt_tcp
 155 #define ip6t_udp xt_udp
 156
 157 /* Values for "inv" field in struct ipt_tcp. */
 158 #define IP6T_TCP_INV_SRCPT      XT_TCP_INV_SRCPT
 159 #define IP6T_TCP_INV_DSTPT      XT_TCP_INV_DSTPT
 160 #define IP6T_TCP_INV_FLAGS      XT_TCP_INV_FLAGS
 161 #define IP6T_TCP_INV_OPTION     XT_TCP_INV_OPTION
 162 #define IP6T_TCP_INV_MASK       XT_TCP_INV_MASK
 163
 164 /* Values for "invflags" field in struct ipt_udp. */
 165 #define IP6T_UDP_INV_SRCPT      XT_UDP_INV_SRCPT
 166 #define IP6T_UDP_INV_DSTPT      XT_UDP_INV_DSTPT
 167 #define IP6T_UDP_INV_MASK       XT_UDP_INV_MASK
 168
 169 /* ICMP matching stuff */
 170 struct ip6t_icmp
 171 {
 172         u_int8_t type;                          /* type to match */
 173         u_int8_t code[2];                       /* range of code */
 174         u_int8_t invflags;                      /* Inverse flags */
 175 };
 176
 177 /* Values for "inv" field for struct ipt_icmp. */
 178 #define IP6T_ICMP_INV   0x01    /* Invert the sense of type/code test */
 179
 180 /* The argument to IP6T_SO_GET_INFO */
 181 struct ip6t_getinfo
 182 {
 183         /* Which table: caller fills this in. */
 184         char name[IP6T_TABLE_MAXNAMELEN];
 185
 186         /* Kernel fills these in. */
 187         /* Which hook entry points are valid: bitmask */
 188         unsigned int valid_hooks;
 189
 190         /* Hook entry points: one per netfilter hook. */
 191         unsigned int hook_entry[NF_IP6_NUMHOOKS];
 192
 193         /* Underflow points. */
 194         unsigned int underflow[NF_IP6_NUMHOOKS];
 195
 196         /* Number of entries */
 197         unsigned int num_entries;
 198
 199         /* Size of entries. */
 200         unsigned int size;
 201 };
 202
 203 /* The argument to IP6T_SO_SET_REPLACE. */
 204 struct ip6t_replace
 205 {
 206         /* Which table. */
 207         char name[IP6T_TABLE_MAXNAMELEN];
 208
 209         /* Which hook entry points are valid: bitmask.  You can't
 210            change this. */
 211         unsigned int valid_hooks;
 212
 213         /* Number of entries */
 214         unsigned int num_entries;
 215
 216         /* Total size of new entries */
 217         unsigned int size;
 218
 219         /* Hook entry points. */
 220         unsigned int hook_entry[NF_IP6_NUMHOOKS];
 221
 222         /* Underflow points. */
 223         unsigned int underflow[NF_IP6_NUMHOOKS];
 224
 225         /* Information about old entries: */
 226         /* Number of counters (must be equal to current number of entries). */
 227         unsigned int num_counters;
 228         /* The old entries' counters. */
 229         struct xt_counters __user *counters;
 230
 231         /* The entries (hang off end: not really an array). */
 232         struct ip6t_entry entries[0];
 233 };
 234
 235 /* The argument to IP6T_SO_ADD_COUNTERS. */
 236 #define ip6t_counters_info xt_counters_info
 237
 238 /* The argument to IP6T_SO_GET_ENTRIES. */
 239 struct ip6t_get_entries
 240 {
 241         /* Which table: user fills this in. */
 242         char name[IP6T_TABLE_MAXNAMELEN];
 243
 244         /* User fills this in: total entry size. */
 245         unsigned int size;
 246
 247         /* The entries. */
 248         struct ip6t_entry entrytable[0];
 249 };
 250
 251 /* Standard return verdict, or do jump. */
 252 #define IP6T_STANDARD_TARGET XT_STANDARD_TARGET
 253 /* Error verdict. */
 254 #define IP6T_ERROR_TARGET XT_ERROR_TARGET
 255
 256 /* Helper functions */
 257 static __inline__ struct ip6t_entry_target *
 258 ip6t_get_target(struct ip6t_entry *e)
 259 {
 260         return (void *)e + e->target_offset;
 261 }
 262
 263 /* fn returns 0 to continue iteration */
 264 #define IP6T_MATCH_ITERATE(e, fn, args...)      \
 265 ({                                              \
 266         unsigned int __i;                       \
 267         int __ret = 0;                          \
 268         struct ip6t_entry_match *__m;           \
 269                                                 \
 270         for (__i = sizeof(struct ip6t_entry);   \
 271              __i < (e)->target_offset;          \
 272              __i += __m->u.match_size) {        \
 273                 __m = (void *)(e) + __i;        \
 274                                                 \
 275                 __ret = fn(__m , ## args);      \
 276                 if (__ret != 0)                 \
 277                         break;                  \
 278         }                                       \
 279         __ret;                                  \
 280 })
 281
 282 /* fn returns 0 to continue iteration */
 283 #define IP6T_ENTRY_ITERATE(entries, size, fn, args...)          \
 284 ({                                                              \
 285         unsigned int __i;                                       \
 286         int __ret = 0;                                          \
 287         struct ip6t_entry *__e;                                 \
 288                                                                 \
 289         for (__i = 0; __i < (size); __i += __e->next_offset) {  \
 290                 __e = (void *)(entries) + __i;                  \
 291                                                                 \
 292                 __ret = fn(__e , ## args);                      \
 293                 if (__ret != 0)                                 \
 294                         break;                                  \
 295         }                                                       \
 296         __ret;                                                  \
 297 })
 298
 299 /*
 300  *      Main firewall chains definitions and global var's definitions.
 301  */
 302
 303 #ifdef __KERNEL__
 304
 305 #include <linux/init.h>
 306 extern void ip6t_init(void) __init;
 307
 308 extern int ip6t_register_table(struct xt_table *table,
 309                                const struct ip6t_replace *repl);
 310 extern void ip6t_unregister_table(struct xt_table *table);
 311 extern unsigned int ip6t_do_table(struct sk_buff **pskb,
 312                                   unsigned int hook,
 313                                   const struct net_device *in,
 314                                   const struct net_device *out,
 315                                   struct xt_table *table);
 316
 317 /* Check for an extension */
 318 extern int ip6t_ext_hdr(u8 nexthdr);
 319 /* find specified header and get offset to it */
 320 extern int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset,
 321                          int target, unsigned short *fragoff);
 322
 323 extern int ip6_masked_addrcmp(const struct in6_addr *addr1,
 324                               const struct in6_addr *mask,
 325                               const struct in6_addr *addr2);
 326
 327 #define IP6T_ALIGN(s) (((s) + (__alignof__(struct ip6t_entry)-1)) & ~(__alignof__(struct ip6t_entry)-1))
 328
 329 #endif /*__KERNEL__*/
 330 #endif /* _IP6_TABLES_H */