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#define ipt_entry_match xt_entry_match 31#define ipt_entry_target xt_entry_target 32#define ipt_standard_target xt_standard_target 33#define ipt_error_target xt_error_target 34#define ipt_counters xt_counters 35#define IPT_CONTINUE XT_CONTINUE 36#define IPT_RETURN XT_RETURN 37 38/* This group is older than old (iptables < v1.4.0-rc1~89) */ 39#include <linux/netfilter/xt_tcpudp.h> 40#define ipt_udp xt_udp 41#define ipt_tcp xt_tcp 42#define IPT_TCP_INV_SRCPT XT_TCP_INV_SRCPT 43#define IPT_TCP_INV_DSTPT XT_TCP_INV_DSTPT 44#define IPT_TCP_INV_FLAGS XT_TCP_INV_FLAGS 45#define IPT_TCP_INV_OPTION XT_TCP_INV_OPTION 46#define IPT_TCP_INV_MASK XT_TCP_INV_MASK 47#define IPT_UDP_INV_SRCPT XT_UDP_INV_SRCPT 48#define IPT_UDP_INV_DSTPT XT_UDP_INV_DSTPT 49#define IPT_UDP_INV_MASK XT_UDP_INV_MASK 50 51/* The argument to IPT_SO_ADD_COUNTERS. */ 52#define ipt_counters_info xt_counters_info 53/* Standard return verdict, or do jump. */ 54#define IPT_STANDARD_TARGET XT_STANDARD_TARGET 55/* Error verdict. */ 56#define IPT_ERROR_TARGET XT_ERROR_TARGET 57 58/* fn returns 0 to continue iteration */ 59#define IPT_MATCH_ITERATE(e, fn, args...) \ 60 XT_MATCH_ITERATE(struct ipt_entry, e, fn, ## args) 61 62/* fn returns 0 to continue iteration */ 63#define IPT_ENTRY_ITERATE(entries, size, fn, args...) \ 64 XT_ENTRY_ITERATE(struct ipt_entry, entries, size, fn, ## args) 65 66/* Yes, Virginia, you have to zero the padding. */ 67struct ipt_ip { 68 /* Source and destination IP addr */ 69 struct in_addr src, dst; 70 /* Mask for src and dest IP addr */ 71 struct in_addr smsk, dmsk; 72 char iniface[IFNAMSIZ], outiface[IFNAMSIZ]; 73 unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ]; 74 75 /* Protocol, 0 = ANY */ 76 __u16 proto; 77 78 /* Flags word */ 79 __u8 flags; 80 /* Inverse flags */ 81 __u8 invflags; 82}; 83 84/* Values for "flag" field in struct ipt_ip (general ip structure). */ 85#define IPT_F_FRAG 0x01 /* Set if rule is a fragment rule */ 86#define IPT_F_GOTO 0x02 /* Set if jump is a goto */ 87#define IPT_F_MASK 0x03 /* All possible flag bits mask. */ 88 89/* Values for "inv" field in struct ipt_ip. */ 90#define IPT_INV_VIA_IN 0x01 /* Invert the sense of IN IFACE. */ 91#define IPT_INV_VIA_OUT 0x02 /* Invert the sense of OUT IFACE */ 92#define IPT_INV_TOS 0x04 /* Invert the sense of TOS. */ 93#define IPT_INV_SRCIP 0x08 /* Invert the sense of SRC IP. */ 94#define IPT_INV_DSTIP 0x10 /* Invert the sense of DST OP. */ 95#define IPT_INV_FRAG 0x20 /* Invert the sense of FRAG. */ 96#define IPT_INV_PROTO XT_INV_PROTO 97#define IPT_INV_MASK 0x7F /* All possible flag bits mask. */ 98 99/* This structure defines each of the firewall rules. Consists of 3 100 parts which are 1) general IP header stuff 2) match specific 101 stuff 3) the target to perform if the rule matches */ 102struct ipt_entry { 103 struct ipt_ip ip; 104 105 /* Mark with fields that we care about. */ 106 unsigned int nfcache; 107 108 /* Size of ipt_entry + matches */ 109 __u16 target_offset; 110 /* Size of ipt_entry + matches + target */ 111 __u16 next_offset; 112 113 /* Back pointer */ 114 unsigned int comefrom; 115 116 /* Packet and byte counters. */ 117 struct xt_counters counters; 118 119 /* The matches (if any), then the target. */ 120 unsigned char elems[0]; 121}; 122 123/* 124 * New IP firewall options for [gs]etsockopt at the RAW IP level. 125 * Unlike BSD Linux inherits IP options so you don't have to use a raw 126 * socket for this. Instead we check rights in the calls. 127 * 128 * ATTENTION: check linux/in.h before adding new number here. 129 */ 130#define IPT_BASE_CTL 64 131 132#define IPT_SO_SET_REPLACE (IPT_BASE_CTL) 133#define IPT_SO_SET_ADD_COUNTERS (IPT_BASE_CTL + 1) 134#define IPT_SO_SET_MAX IPT_SO_SET_ADD_COUNTERS 135 136#define IPT_SO_GET_INFO (IPT_BASE_CTL) 137#define IPT_SO_GET_ENTRIES (IPT_BASE_CTL + 1) 138#define IPT_SO_GET_REVISION_MATCH (IPT_BASE_CTL + 2) 139#define IPT_SO_GET_REVISION_TARGET (IPT_BASE_CTL + 3) 140#define IPT_SO_GET_MAX IPT_SO_GET_REVISION_TARGET 141 142/* ICMP matching stuff */ 143struct ipt_icmp { 144 __u8 type; /* type to match */ 145 __u8 code[2]; /* range of code */ 146 __u8 invflags; /* Inverse flags */ 147}; 148 149/* Values for "inv" field for struct ipt_icmp. */ 150#define IPT_ICMP_INV 0x01 /* Invert the sense of type/code test */ 151 152/* The argument to IPT_SO_GET_INFO */ 153struct ipt_getinfo { 154 /* Which table: caller fills this in. */ 155 char name[XT_TABLE_MAXNAMELEN]; 156 157 /* Kernel fills these in. */ 158 /* Which hook entry points are valid: bitmask */ 159 unsigned int valid_hooks; 160 161 /* Hook entry points: one per netfilter hook. */ 162 unsigned int hook_entry[NF_INET_NUMHOOKS]; 163 164 /* Underflow points. */ 165 unsigned int underflow[NF_INET_NUMHOOKS]; 166 167 /* Number of entries */ 168 unsigned int num_entries; 169 170 /* Size of entries. */ 171 unsigned int size; 172}; 173 174/* The argument to IPT_SO_SET_REPLACE. */ 175struct ipt_replace { 176 /* Which table. */ 177 char name[XT_TABLE_MAXNAMELEN]; 178 179 /* Which hook entry points are valid: bitmask. You can't 180 change this. */ 181 unsigned int valid_hooks; 182 183 /* Number of entries */ 184 unsigned int num_entries; 185 186 /* Total size of new entries */ 187 unsigned int size; 188 189 /* Hook entry points. */ 190 unsigned int hook_entry[NF_INET_NUMHOOKS]; 191 192 /* Underflow points. */ 193 unsigned int underflow[NF_INET_NUMHOOKS]; 194 195 /* Information about old entries: */ 196 /* Number of counters (must be equal to current number of entries). */ 197 unsigned int num_counters; 198 /* The old entries' counters. */ 199 struct xt_counters *counters; 200 201 /* The entries (hang off end: not really an array). */ 202 struct ipt_entry entries[0]; 203}; 204 205/* The argument to IPT_SO_GET_ENTRIES. */ 206struct ipt_get_entries { 207 /* Which table: user fills this in. */ 208 char name[XT_TABLE_MAXNAMELEN]; 209 210 /* User fills this in: total entry size. */ 211 unsigned int size; 212 213 /* The entries. */ 214 struct ipt_entry entrytable[0]; 215}; 216 217/* Helper functions */ 218static __inline__ struct xt_entry_target * 219ipt_get_target(struct ipt_entry *e) 220{ 221 return (void *)e + e->target_offset; 222} 223 224/* 225 * Main firewall chains definitions and global var's definitions. 226 */ 227#endif /* _IPTABLES_H */ 228