1/* 2 * ebtables 3 * 4 * Authors: 5 * Bart De Schuymer <bdschuym@pandora.be> 6 * 7 * ebtables.c,v 2.0, April, 2002 8 * 9 * This code is stongly inspired on the iptables code which is 10 * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling 11 */ 12 13#ifndef _UAPI__LINUX_BRIDGE_EFF_H 14#define _UAPI__LINUX_BRIDGE_EFF_H 15#include <linux/if.h> 16#include <linux/netfilter_bridge.h> 17#include <linux/if_ether.h> 18 19#define EBT_TABLE_MAXNAMELEN 32 20#define EBT_CHAIN_MAXNAMELEN EBT_TABLE_MAXNAMELEN 21#define EBT_FUNCTION_MAXNAMELEN EBT_TABLE_MAXNAMELEN 22 23/* verdicts >0 are "branches" */ 24#define EBT_ACCEPT -1 25#define EBT_DROP -2 26#define EBT_CONTINUE -3 27#define EBT_RETURN -4 28#define NUM_STANDARD_TARGETS 4 29/* ebtables target modules store the verdict inside an int. We can 30 * reclaim a part of this int for backwards compatible extensions. 31 * The 4 lsb are more than enough to store the verdict. */ 32#define EBT_VERDICT_BITS 0x0000000F 33 34struct xt_match; 35struct xt_target; 36 37struct ebt_counter { 38 uint64_t pcnt; 39 uint64_t bcnt; 40}; 41 42struct ebt_replace { 43 char name[EBT_TABLE_MAXNAMELEN]; 44 unsigned int valid_hooks; 45 /* nr of rules in the table */ 46 unsigned int nentries; 47 /* total size of the entries */ 48 unsigned int entries_size; 49 /* start of the chains */ 50 struct ebt_entries __user *hook_entry[NF_BR_NUMHOOKS]; 51 /* nr of counters userspace expects back */ 52 unsigned int num_counters; 53 /* where the kernel will put the old counters */ 54 struct ebt_counter __user *counters; 55 char __user *entries; 56}; 57 58struct ebt_replace_kernel { 59 char name[EBT_TABLE_MAXNAMELEN]; 60 unsigned int valid_hooks; 61 /* nr of rules in the table */ 62 unsigned int nentries; 63 /* total size of the entries */ 64 unsigned int entries_size; 65 /* start of the chains */ 66 struct ebt_entries *hook_entry[NF_BR_NUMHOOKS]; 67 /* nr of counters userspace expects back */ 68 unsigned int num_counters; 69 /* where the kernel will put the old counters */ 70 struct ebt_counter *counters; 71 char *entries; 72}; 73 74struct ebt_entries { 75 /* this field is always set to zero 76 * See EBT_ENTRY_OR_ENTRIES. 77 * Must be same size as ebt_entry.bitmask */ 78 unsigned int distinguisher; 79 /* the chain name */ 80 char name[EBT_CHAIN_MAXNAMELEN]; 81 /* counter offset for this chain */ 82 unsigned int counter_offset; 83 /* one standard (accept, drop, return) per hook */ 84 int policy; 85 /* nr. of entries */ 86 unsigned int nentries; 87 /* entry list */ 88 char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace)))); 89}; 90 91/* used for the bitmask of struct ebt_entry */ 92 93/* This is a hack to make a difference between an ebt_entry struct and an 94 * ebt_entries struct when traversing the entries from start to end. 95 * Using this simplifies the code a lot, while still being able to use 96 * ebt_entries. 97 * Contrary, iptables doesn't use something like ebt_entries and therefore uses 98 * different techniques for naming the policy and such. So, iptables doesn't 99 * need a hack like this. 100 */ 101#define EBT_ENTRY_OR_ENTRIES 0x01 102/* these are the normal masks */ 103#define EBT_NOPROTO 0x02 104#define EBT_802_3 0x04 105#define EBT_SOURCEMAC 0x08 106#define EBT_DESTMAC 0x10 107#define EBT_F_MASK (EBT_NOPROTO | EBT_802_3 | EBT_SOURCEMAC | EBT_DESTMAC \ 108 | EBT_ENTRY_OR_ENTRIES) 109 110#define EBT_IPROTO 0x01 111#define EBT_IIN 0x02 112#define EBT_IOUT 0x04 113#define EBT_ISOURCE 0x8 114#define EBT_IDEST 0x10 115#define EBT_ILOGICALIN 0x20 116#define EBT_ILOGICALOUT 0x40 117#define EBT_INV_MASK (EBT_IPROTO | EBT_IIN | EBT_IOUT | EBT_ILOGICALIN \ 118 | EBT_ILOGICALOUT | EBT_ISOURCE | EBT_IDEST) 119 120struct ebt_entry_match { 121 union { 122 char name[EBT_FUNCTION_MAXNAMELEN]; 123 struct xt_match *match; 124 } u; 125 /* size of data */ 126 unsigned int match_size; 127 unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace)))); 128}; 129 130struct ebt_entry_watcher { 131 union { 132 char name[EBT_FUNCTION_MAXNAMELEN]; 133 struct xt_target *watcher; 134 } u; 135 /* size of data */ 136 unsigned int watcher_size; 137 unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace)))); 138}; 139 140struct ebt_entry_target { 141 union { 142 char name[EBT_FUNCTION_MAXNAMELEN]; 143 struct xt_target *target; 144 } u; 145 /* size of data */ 146 unsigned int target_size; 147 unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace)))); 148}; 149 150#define EBT_STANDARD_TARGET "standard" 151struct ebt_standard_target { 152 struct ebt_entry_target target; 153 int verdict; 154}; 155 156/* one entry */ 157struct ebt_entry { 158 /* this needs to be the first field */ 159 unsigned int bitmask; 160 unsigned int invflags; 161 __be16 ethproto; 162 /* the physical in-dev */ 163 char in[IFNAMSIZ]; 164 /* the logical in-dev */ 165 char logical_in[IFNAMSIZ]; 166 /* the physical out-dev */ 167 char out[IFNAMSIZ]; 168 /* the logical out-dev */ 169 char logical_out[IFNAMSIZ]; 170 unsigned char sourcemac[ETH_ALEN]; 171 unsigned char sourcemsk[ETH_ALEN]; 172 unsigned char destmac[ETH_ALEN]; 173 unsigned char destmsk[ETH_ALEN]; 174 /* sizeof ebt_entry + matches */ 175 unsigned int watchers_offset; 176 /* sizeof ebt_entry + matches + watchers */ 177 unsigned int target_offset; 178 /* sizeof ebt_entry + matches + watchers + target */ 179 unsigned int next_offset; 180 unsigned char elems[0] __attribute__ ((aligned (__alignof__(struct ebt_replace)))); 181}; 182 183/* {g,s}etsockopt numbers */ 184#define EBT_BASE_CTL 128 185 186#define EBT_SO_SET_ENTRIES (EBT_BASE_CTL) 187#define EBT_SO_SET_COUNTERS (EBT_SO_SET_ENTRIES+1) 188#define EBT_SO_SET_MAX (EBT_SO_SET_COUNTERS+1) 189 190#define EBT_SO_GET_INFO (EBT_BASE_CTL) 191#define EBT_SO_GET_ENTRIES (EBT_SO_GET_INFO+1) 192#define EBT_SO_GET_INIT_INFO (EBT_SO_GET_ENTRIES+1) 193#define EBT_SO_GET_INIT_ENTRIES (EBT_SO_GET_INIT_INFO+1) 194#define EBT_SO_GET_MAX (EBT_SO_GET_INIT_ENTRIES+1) 195 196 197/* blatently stolen from ip_tables.h 198 * fn returns 0 to continue iteration */ 199#define EBT_MATCH_ITERATE(e, fn, args...) \ 200({ \ 201 unsigned int __i; \ 202 int __ret = 0; \ 203 struct ebt_entry_match *__match; \ 204 \ 205 for (__i = sizeof(struct ebt_entry); \ 206 __i < (e)->watchers_offset; \ 207 __i += __match->match_size + \ 208 sizeof(struct ebt_entry_match)) { \ 209 __match = (void *)(e) + __i; \ 210 \ 211 __ret = fn(__match , ## args); \ 212 if (__ret != 0) \ 213 break; \ 214 } \ 215 if (__ret == 0) { \ 216 if (__i != (e)->watchers_offset) \ 217 __ret = -EINVAL; \ 218 } \ 219 __ret; \ 220}) 221 222#define EBT_WATCHER_ITERATE(e, fn, args...) \ 223({ \ 224 unsigned int __i; \ 225 int __ret = 0; \ 226 struct ebt_entry_watcher *__watcher; \ 227 \ 228 for (__i = e->watchers_offset; \ 229 __i < (e)->target_offset; \ 230 __i += __watcher->watcher_size + \ 231 sizeof(struct ebt_entry_watcher)) { \ 232 __watcher = (void *)(e) + __i; \ 233 \ 234 __ret = fn(__watcher , ## args); \ 235 if (__ret != 0) \ 236 break; \ 237 } \ 238 if (__ret == 0) { \ 239 if (__i != (e)->target_offset) \ 240 __ret = -EINVAL; \ 241 } \ 242 __ret; \ 243}) 244 245#define EBT_ENTRY_ITERATE(entries, size, fn, args...) \ 246({ \ 247 unsigned int __i; \ 248 int __ret = 0; \ 249 struct ebt_entry *__entry; \ 250 \ 251 for (__i = 0; __i < (size);) { \ 252 __entry = (void *)(entries) + __i; \ 253 __ret = fn(__entry , ## args); \ 254 if (__ret != 0) \ 255 break; \ 256 if (__entry->bitmask != 0) \ 257 __i += __entry->next_offset; \ 258 else \ 259 __i += sizeof(struct ebt_entries); \ 260 } \ 261 if (__ret == 0) { \ 262 if (__i != (size)) \ 263 __ret = -EINVAL; \ 264 } \ 265 __ret; \ 266}) 267 268#endif /* _UAPI__LINUX_BRIDGE_EFF_H */ 269