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 IP 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 _IPTABLES_H 16#define _IPTABLES_H 17 18#include <linux/types.h> 19 20#include <linux/netfilter_ipv4.h> 21 22#include <linux/netfilter/x_tables.h> 23 24#define IPT_FUNCTION_MAXNAMELEN XT_FUNCTION_MAXNAMELEN 25#define IPT_TABLE_MAXNAMELEN XT_TABLE_MAXNAMELEN 26#define ipt_match xt_match 27#define ipt_target xt_target 28#define ipt_table xt_table 29#define ipt_get_revision xt_get_revision 30 31/* Yes, Virginia, you have to zero the padding. */ 32struct ipt_ip { 33 /* Source and destination IP addr */ 34 struct in_addr src, dst; 35 /* Mask for src and dest IP addr */ 36 struct in_addr smsk, dmsk; 37 char iniface[IFNAMSIZ], outiface[IFNAMSIZ]; 38 unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ]; 39 40 /* Protocol, 0 = ANY */ 41 u_int16_t proto; 42 43 /* Flags word */ 44 u_int8_t flags; 45 /* Inverse flags */ 46 u_int8_t invflags; 47}; 48 49#define ipt_entry_match xt_entry_match 50#define ipt_entry_target xt_entry_target 51#define ipt_standard_target xt_standard_target 52 53#define ipt_counters xt_counters 54 55/* Values for "flag" field in struct ipt_ip (general ip structure). */ 56#define IPT_F_FRAG 0x01 /* Set if rule is a fragment rule */ 57#define IPT_F_GOTO 0x02 /* Set if jump is a goto */ 58#define IPT_F_MASK 0x03 /* All possible flag bits mask. */ 59 60/* Values for "inv" field in struct ipt_ip. */ 61#define IPT_INV_VIA_IN 0x01 /* Invert the sense of IN IFACE. */ 62#define IPT_INV_VIA_OUT 0x02 /* Invert the sense of OUT IFACE */ 63#define IPT_INV_TOS 0x04 /* Invert the sense of TOS. */ 64#define IPT_INV_SRCIP 0x08 /* Invert the sense of SRC IP. */ 65#define IPT_INV_DSTIP 0x10 /* Invert the sense of DST OP. */ 66#define IPT_INV_FRAG 0x20 /* Invert the sense of FRAG. */ 67#define IPT_INV_PROTO XT_INV_PROTO 68#define IPT_INV_MASK 0x7F /* All possible flag bits mask. */ 69#define IPT_F_NO_DEF_MATCH 0x80 /* Internal: no default match rules present */ 70 71/* This structure defines each of the firewall rules. Consists of 3 72 parts which are 1) general IP header stuff 2) match specific 73 stuff 3) the target to perform if the rule matches */ 74struct ipt_entry { 75 struct ipt_ip ip; 76 77 /* Mark with fields that we care about. */ 78 unsigned int nfcache; 79 80 /* Size of ipt_entry + matches */ 81 u_int16_t target_offset; 82 /* Size of ipt_entry + matches + target */ 83 u_int16_t next_offset; 84 85 /* Back pointer */ 86 unsigned int comefrom; 87 88 /* Packet and byte counters. */ 89 struct xt_counters counters; 90 91 /* The matches (if any), then the target. */ 92 unsigned char elems[0]; 93}; 94 95/* 96 * New IP firewall options for [gs]etsockopt at the RAW IP level. 97 * Unlike BSD Linux inherits IP options so you don't have to use a raw 98 * socket for this. Instead we check rights in the calls. 99 * 100 * ATTENTION: check linux/in.h before adding new number here. 101 */ 102#define IPT_BASE_CTL 64 103 104#define IPT_SO_SET_REPLACE (IPT_BASE_CTL) 105#define IPT_SO_SET_ADD_COUNTERS (IPT_BASE_CTL + 1) 106#define IPT_SO_SET_MAX IPT_SO_SET_ADD_COUNTERS 107 108#define IPT_SO_GET_INFO (IPT_BASE_CTL) 109#define IPT_SO_GET_ENTRIES (IPT_BASE_CTL + 1) 110#define IPT_SO_GET_REVISION_MATCH (IPT_BASE_CTL + 2) 111#define IPT_SO_GET_REVISION_TARGET (IPT_BASE_CTL + 3) 112#define IPT_SO_GET_MAX IPT_SO_GET_REVISION_TARGET 113 114#define IPT_CONTINUE XT_CONTINUE 115#define IPT_RETURN XT_RETURN 116 117#include <linux/netfilter/xt_tcpudp.h> 118#define ipt_udp xt_udp 119#define ipt_tcp xt_tcp 120 121#define IPT_TCP_INV_SRCPT XT_TCP_INV_SRCPT 122#define IPT_TCP_INV_DSTPT XT_TCP_INV_DSTPT 123#define IPT_TCP_INV_FLAGS XT_TCP_INV_FLAGS 124#define IPT_TCP_INV_OPTION XT_TCP_INV_OPTION 125#define IPT_TCP_INV_MASK XT_TCP_INV_MASK 126 127#define IPT_UDP_INV_SRCPT XT_UDP_INV_SRCPT 128#define IPT_UDP_INV_DSTPT XT_UDP_INV_DSTPT 129#define IPT_UDP_INV_MASK XT_UDP_INV_MASK 130 131/* ICMP matching stuff */ 132struct ipt_icmp { 133 u_int8_t type; /* type to match */ 134 u_int8_t code[2]; /* range of code */ 135 u_int8_t invflags; /* Inverse flags */ 136}; 137 138/* Values for "inv" field for struct ipt_icmp. */ 139#define IPT_ICMP_INV 0x01 /* Invert the sense of type/code test */ 140 141/* The argument to IPT_SO_GET_INFO */ 142struct ipt_getinfo { 143 /* Which table: caller fills this in. */ 144 char name[IPT_TABLE_MAXNAMELEN]; 145 146 /* Kernel fills these in. */ 147 /* Which hook entry points are valid: bitmask */ 148 unsigned int valid_hooks; 149 150 /* Hook entry points: one per netfilter hook. */ 151 unsigned int hook_entry[NF_INET_NUMHOOKS]; 152 153 /* Underflow points. */ 154 unsigned int underflow[NF_INET_NUMHOOKS]; 155 156 /* Number of entries */ 157 unsigned int num_entries; 158 159 /* Size of entries. */ 160 unsigned int size; 161}; 162 163/* The argument to IPT_SO_SET_REPLACE. */ 164struct ipt_replace { 165 /* Which table. */ 166 char name[IPT_TABLE_MAXNAMELEN]; 167 168 /* Which hook entry points are valid: bitmask. You can't 169 change this. */ 170 unsigned int valid_hooks; 171 172 /* Number of entries */ 173 unsigned int num_entries; 174 175 /* Total size of new entries */ 176 unsigned int size; 177 178 /* Hook entry points. */ 179 unsigned int hook_entry[NF_INET_NUMHOOKS]; 180 181 /* Underflow points. */ 182 unsigned int underflow[NF_INET_NUMHOOKS]; 183 184 /* Information about old entries: */ 185 /* Number of counters (must be equal to current number of entries). */ 186 unsigned int num_counters; 187 /* The old entries' counters. */ 188 struct xt_counters *counters; 189 190 /* The entries (hang off end: not really an array). */ 191 struct ipt_entry entries[0]; 192}; 193 194/* The argument to IPT_SO_ADD_COUNTERS. */ 195#define ipt_counters_info xt_counters_info 196 197/* The argument to IPT_SO_GET_ENTRIES. */ 198struct ipt_get_entries { 199 /* Which table: user fills this in. */ 200 char name[IPT_TABLE_MAXNAMELEN]; 201 202 /* User fills this in: total entry size. */ 203 unsigned int size; 204 205 /* The entries. */ 206 struct ipt_entry entrytable[0]; 207}; 208 209/* Standard return verdict, or do jump. */ 210#define IPT_STANDARD_TARGET XT_STANDARD_TARGET 211/* Error verdict. */ 212#define IPT_ERROR_TARGET XT_ERROR_TARGET 213 214/* Helper functions */ 215static __inline__ struct ipt_entry_target * 216ipt_get_target(struct ipt_entry *e) 217{ 218 return (void *)e + e->target_offset; 219} 220 221/* fn returns 0 to continue iteration */ 222#define IPT_MATCH_ITERATE(e, fn, args...) \ 223 XT_MATCH_ITERATE(struct ipt_entry, e, fn, ## args) 224 225/* fn returns 0 to continue iteration */ 226#define IPT_ENTRY_ITERATE(entries, size, fn, args...) \ 227 XT_ENTRY_ITERATE(struct ipt_entry, entries, size, fn, ## args) 228 229/* 230 * Main firewall chains definitions and global var's definitions. 231 */ 232#endif /* _IPTABLES_H */ 233