diff options
Diffstat (limited to 'include/linux/netfilter_bridge/ebtables.h')
-rw-r--r-- | include/linux/netfilter_bridge/ebtables.h | 363 |
1 files changed, 363 insertions, 0 deletions
diff --git a/include/linux/netfilter_bridge/ebtables.h b/include/linux/netfilter_bridge/ebtables.h new file mode 100644 index 0000000..b1a7cc9 --- /dev/null +++ b/include/linux/netfilter_bridge/ebtables.h @@ -0,0 +1,363 @@ +/* + * ebtables + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * + * ebtables.c,v 2.0, April, 2002 + * + * This code is stongly inspired on 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/if.h> +#include <linux/netfilter_bridge.h> +#include <linux/if_ether.h> + +#define EBT_TABLE_MAXNAMELEN 32 +#define EBT_CHAIN_MAXNAMELEN EBT_TABLE_MAXNAMELEN +#define EBT_FUNCTION_MAXNAMELEN EBT_TABLE_MAXNAMELEN + +/* 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 + +struct ebt_counter +{ + uint64_t pcnt; + uint64_t 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_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 alot, 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 { + char name[EBT_FUNCTION_MAXNAMELEN]; + struct ebt_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 { + char name[EBT_FUNCTION_MAXNAMELEN]; + struct ebt_watcher *watcher; + } u; + /* size of data */ + unsigned int watcher_size; + unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace)))); +}; + +struct ebt_entry_target +{ + union { + char name[EBT_FUNCTION_MAXNAMELEN]; + struct ebt_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; + uint16_t 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]; + /* 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)))); +}; + +/* {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) + +#ifdef __KERNEL__ + +/* return values for match() functions */ +#define EBT_MATCH 0 +#define EBT_NOMATCH 1 + +struct ebt_match +{ + struct list_head list; + const char name[EBT_FUNCTION_MAXNAMELEN]; + /* 0 == it matches */ + int (*match)(const struct sk_buff *skb, const struct net_device *in, + const struct net_device *out, const void *matchdata, + unsigned int datalen); + /* 0 == let it in */ + int (*check)(const char *tablename, unsigned int hookmask, + const struct ebt_entry *e, void *matchdata, unsigned int datalen); + void (*destroy)(void *matchdata, unsigned int datalen); + struct module *me; +}; + +struct ebt_watcher +{ + struct list_head list; + const char name[EBT_FUNCTION_MAXNAMELEN]; + void (*watcher)(const struct sk_buff *skb, unsigned int hooknr, + const struct net_device *in, const struct net_device *out, + const void *watcherdata, unsigned int datalen); + /* 0 == let it in */ + int (*check)(const char *tablename, unsigned int hookmask, + const struct ebt_entry *e, void *watcherdata, unsigned int datalen); + void (*destroy)(void *watcherdata, unsigned int datalen); + struct module *me; +}; + +struct ebt_target +{ + struct list_head list; + const char name[EBT_FUNCTION_MAXNAMELEN]; + /* returns one of the standard verdicts */ + int (*target)(struct sk_buff **pskb, unsigned int hooknr, + const struct net_device *in, const struct net_device *out, + const void *targetdata, unsigned int datalen); + /* 0 == let it in */ + int (*check)(const char *tablename, unsigned int hookmask, + const struct ebt_entry *e, void *targetdata, unsigned int datalen); + void (*destroy)(void *targetdata, unsigned int datalen); + struct module *me; +}; + +/* used for jumping from and into user defined chains (udc) */ +struct ebt_chainstack +{ + struct ebt_entries *chaininfo; /* pointer to chain data */ + struct ebt_entry *e; /* pointer to entry data */ + unsigned int n; /* n'th entry */ +}; + +struct ebt_table_info +{ + /* total size of the entries */ + unsigned int entries_size; + unsigned int nentries; + /* pointers to the start of the chains */ + struct ebt_entries *hook_entry[NF_BR_NUMHOOKS]; + /* room to maintain the stack used for jumping from and into udc */ + struct ebt_chainstack **chainstack; + char *entries; + struct ebt_counter counters[0] ____cacheline_aligned; +}; + +struct ebt_table +{ + struct list_head list; + char name[EBT_TABLE_MAXNAMELEN]; + struct ebt_replace *table; + unsigned int valid_hooks; + rwlock_t lock; + /* e.g. could be the table explicitly only allows certain + * matches, targets, ... 0 == let it in */ + int (*check)(const struct ebt_table_info *info, + unsigned int valid_hooks); + /* the data used by the kernel */ + struct ebt_table_info *private; + struct module *me; +}; + +#define EBT_ALIGN(s) (((s) + (__alignof__(struct ebt_replace)-1)) & \ + ~(__alignof__(struct ebt_replace)-1)) +extern int ebt_register_table(struct ebt_table *table); +extern void ebt_unregister_table(struct ebt_table *table); +extern int ebt_register_match(struct ebt_match *match); +extern void ebt_unregister_match(struct ebt_match *match); +extern int ebt_register_watcher(struct ebt_watcher *watcher); +extern void ebt_unregister_watcher(struct ebt_watcher *watcher); +extern int ebt_register_target(struct ebt_target *target); +extern void ebt_unregister_target(struct ebt_target *target); +extern unsigned int ebt_do_table(unsigned int hook, struct sk_buff **pskb, + const struct net_device *in, const struct net_device *out, + struct ebt_table *table); + +/* Used in the kernel match() functions */ +#define FWINV(bool,invflg) ((bool) ^ !!(info->invflags & invflg)) +/* True if the hook mask denotes that the rule is in a base chain, + * used in the check() functions */ +#define BASE_CHAIN (hookmask & (1 << NF_BR_NUMHOOKS)) +/* Clear the bit in the hook mask that tells if the rule is on a base chain */ +#define CLEAR_BASE_CHAIN_BIT (hookmask &= ~(1 << NF_BR_NUMHOOKS)) +/* True if the target is not a standard target */ +#define INVALID_TARGET (info->target < -NUM_STANDARD_TARGETS || info->target >= 0) + +#endif /* __KERNEL__ */ + +/* 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 |