/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ /* * ebtables * * Authors: * Bart De Schuymer <bdschuym@pandora.be> * * ebtables.c,v 2.0, April, 2002 * * This code is strongly inspired by the iptables code which is * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling */ #ifndef __LINUX_BRIDGE_EFF_H #define __LINUX_BRIDGE_EFF_H #include <linux/types.h> #include <linux/if.h> #include <linux/netfilter_bridge.h> #define EBT_TABLE_MAXNAMELEN 32 #define EBT_CHAIN_MAXNAMELEN EBT_TABLE_MAXNAMELEN #define EBT_FUNCTION_MAXNAMELEN EBT_TABLE_MAXNAMELEN #define EBT_EXTENSION_MAXNAMELEN 31 /* verdicts >0 are "branches" */ #define EBT_ACCEPT -1 #define EBT_DROP -2 #define EBT_CONTINUE -3 #define EBT_RETURN -4 #define NUM_STANDARD_TARGETS 4 /* ebtables target modules store the verdict inside an int. We can * reclaim a part of this int for backwards compatible extensions. * The 4 lsb are more than enough to store the verdict. */ #define EBT_VERDICT_BITS 0x0000000F struct xt_match; struct xt_target; struct ebt_counter { __u64 pcnt; __u64 bcnt; }; struct ebt_replace { char name[EBT_TABLE_MAXNAMELEN]; unsigned int valid_hooks; /* nr of rules in the table */ unsigned int nentries; /* total size of the entries */ unsigned int entries_size; /* start of the chains */ struct ebt_entries *hook_entry[NF_BR_NUMHOOKS]; /* nr of counters userspace expects back */ unsigned int num_counters; /* where the kernel will put the old counters */ struct ebt_counter *counters; char *entries; }; struct ebt_replace_kernel { char name[EBT_TABLE_MAXNAMELEN]; unsigned int valid_hooks; /* nr of rules in the table */ unsigned int nentries; /* total size of the entries */ unsigned int entries_size; /* start of the chains */ struct ebt_entries *hook_entry[NF_BR_NUMHOOKS]; /* nr of counters userspace expects back */ unsigned int num_counters; /* where the kernel will put the old counters */ struct ebt_counter *counters; char *entries; }; struct ebt_entries { /* this field is always set to zero * See EBT_ENTRY_OR_ENTRIES. * Must be same size as ebt_entry.bitmask */ unsigned int distinguisher; /* the chain name */ char name[EBT_CHAIN_MAXNAMELEN]; /* counter offset for this chain */ unsigned int counter_offset; /* one standard (accept, drop, return) per hook */ int policy; /* nr. of entries */ unsigned int nentries; /* entry list */ char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace)))); }; /* used for the bitmask of struct ebt_entry */ /* This is a hack to make a difference between an ebt_entry struct and an * ebt_entries struct when traversing the entries from start to end. * Using this simplifies the code a lot, while still being able to use * ebt_entries. * Contrary, iptables doesn't use something like ebt_entries and therefore uses * different techniques for naming the policy and such. So, iptables doesn't * need a hack like this. */ #define EBT_ENTRY_OR_ENTRIES 0x01 /* these are the normal masks */ #define EBT_NOPROTO 0x02 #define EBT_802_3 0x04 #define EBT_SOURCEMAC 0x08 #define EBT_DESTMAC 0x10 #define EBT_F_MASK (EBT_NOPROTO | EBT_802_3 | EBT_SOURCEMAC | EBT_DESTMAC \ | EBT_ENTRY_OR_ENTRIES) #define EBT_IPROTO 0x01 #define EBT_IIN 0x02 #define EBT_IOUT 0x04 #define EBT_ISOURCE 0x8 #define EBT_IDEST 0x10 #define EBT_ILOGICALIN 0x20 #define EBT_ILOGICALOUT 0x40 #define EBT_INV_MASK (EBT_IPROTO | EBT_IIN | EBT_IOUT | EBT_ILOGICALIN \ | EBT_ILOGICALOUT | EBT_ISOURCE | EBT_IDEST) struct ebt_entry_match { union { struct { char name[EBT_EXTENSION_MAXNAMELEN]; __u8 revision; }; struct xt_match *match; } u; /* size of data */ unsigned int match_size; unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace)))); }; struct ebt_entry_watcher { union { struct { char name[EBT_EXTENSION_MAXNAMELEN]; __u8 revision; }; struct xt_target *watcher; } u; /* size of data */ unsigned int watcher_size; unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace)))); }; struct ebt_entry_target { union { struct { char name[EBT_EXTENSION_MAXNAMELEN]; __u8 revision; }; struct xt_target *target; } u; /* size of data */ unsigned int target_size; unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace)))); }; #define EBT_STANDARD_TARGET "standard" struct ebt_standard_target { struct ebt_entry_target target; int verdict; }; /* one entry */ struct ebt_entry { /* this needs to be the first field */ unsigned int bitmask; unsigned int invflags; __be16 ethproto; /* the physical in-dev */ char in[IFNAMSIZ]; /* the logical in-dev */ char logical_in[IFNAMSIZ]; /* the physical out-dev */ char out[IFNAMSIZ]; /* the logical out-dev */ char logical_out[IFNAMSIZ]; unsigned char sourcemac[ETH_ALEN]; unsigned char sourcemsk[ETH_ALEN]; unsigned char destmac[ETH_ALEN]; unsigned char destmsk[ETH_ALEN]; __struct_group(/* no tag */, offsets, /* no attrs */, /* sizeof ebt_entry + matches */ unsigned int watchers_offset; /* sizeof ebt_entry + matches + watchers */ unsigned int target_offset; /* sizeof ebt_entry + matches + watchers + target */ unsigned int next_offset; ); unsigned char elems[0] __attribute__ ((aligned (__alignof__(struct ebt_replace)))); }; static __inline__ struct ebt_entry_target * ebt_get_target(struct ebt_entry *e) { return (struct ebt_entry_target *)((char *)e + e->target_offset); } /* {g,s}etsockopt numbers */ #define EBT_BASE_CTL 128 #define EBT_SO_SET_ENTRIES (EBT_BASE_CTL) #define EBT_SO_SET_COUNTERS (EBT_SO_SET_ENTRIES+1) #define EBT_SO_SET_MAX (EBT_SO_SET_COUNTERS+1) #define EBT_SO_GET_INFO (EBT_BASE_CTL) #define EBT_SO_GET_ENTRIES (EBT_SO_GET_INFO+1) #define EBT_SO_GET_INIT_INFO (EBT_SO_GET_ENTRIES+1) #define EBT_SO_GET_INIT_ENTRIES (EBT_SO_GET_INIT_INFO+1) #define EBT_SO_GET_MAX (EBT_SO_GET_INIT_ENTRIES+1) /* blatently stolen from ip_tables.h * fn returns 0 to continue iteration */ #define EBT_MATCH_ITERATE(e, fn, args...) \ ({ \ unsigned int __i; \ int __ret = 0; \ struct ebt_entry_match *__match; \ \ for (__i = sizeof(struct ebt_entry); \ __i < (e)->watchers_offset; \ __i += __match->match_size + \ sizeof(struct ebt_entry_match)) { \ __match = (void *)(e) + __i; \ \ __ret = fn(__match , ## args); \ if (__ret != 0) \ break; \ } \ if (__ret == 0) { \ if (__i != (e)->watchers_offset) \ __ret = -EINVAL; \ } \ __ret; \ }) #define EBT_WATCHER_ITERATE(e, fn, args...) \ ({ \ unsigned int __i; \ int __ret = 0; \ struct ebt_entry_watcher *__watcher; \ \ for (__i = e->watchers_offset; \ __i < (e)->target_offset; \ __i += __watcher->watcher_size + \ sizeof(struct ebt_entry_watcher)) { \ __watcher = (void *)(e) + __i; \ \ __ret = fn(__watcher , ## args); \ if (__ret != 0) \ break; \ } \ if (__ret == 0) { \ if (__i != (e)->target_offset) \ __ret = -EINVAL; \ } \ __ret; \ }) #define EBT_ENTRY_ITERATE(entries, size, fn, args...) \ ({ \ unsigned int __i; \ int __ret = 0; \ struct ebt_entry *__entry; \ \ for (__i = 0; __i < (size);) { \ __entry = (void *)(entries) + __i; \ __ret = fn(__entry , ## args); \ if (__ret != 0) \ break; \ if (__entry->bitmask != 0) \ __i += __entry->next_offset; \ else \ __i += sizeof(struct ebt_entries); \ } \ if (__ret == 0) { \ if (__i != (size)) \ __ret = -EINVAL; \ } \ __ret; \ }) #endif /* __LINUX_BRIDGE_EFF_H */