mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-29 20:30:35 +00:00
![Harald Welte](/assets/img/avatar_default.png)
This monster-patch tries to do the best job for unifying the data structures and backend interfaces for the three evil clones ip_tables, ip6_tables and arp_tables. In an ideal world we would never have allowed this kind of copy+paste programming... but well, our world isn't (yet?) ideal. o introduce a new x_tables module o {ip,arp,ip6}_tables depend on this x_tables module o registration functions for tables, matches and targets are only wrappers around x_tables provided functions o all matches/targets that are used from ip_tables and ip6_tables are now implemented as xt_FOOBAR.c files and provide module aliases to ipt_FOOBAR and ip6t_FOOBAR o header files for xt_matches are in include/linux/netfilter/, include/linux/netfilter_{ipv4,ipv6} contains compatibility wrappers around the xt_FOOBAR.h headers Based on this patchset we're going to further unify the code, gradually getting rid of all the layer 3 specific assumptions. Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
281 lines
7.5 KiB
C
281 lines
7.5 KiB
C
/*
|
|
* Format of an ARP firewall descriptor
|
|
*
|
|
* src, tgt, src_mask, tgt_mask, arpop, arpop_mask are always stored in
|
|
* network byte order.
|
|
* flags are stored in host byte order (of course).
|
|
*/
|
|
|
|
#ifndef _ARPTABLES_H
|
|
#define _ARPTABLES_H
|
|
|
|
#ifdef __KERNEL__
|
|
#include <linux/if.h>
|
|
#include <linux/types.h>
|
|
#include <linux/in.h>
|
|
#include <linux/if_arp.h>
|
|
#include <linux/skbuff.h>
|
|
#endif
|
|
#include <linux/compiler.h>
|
|
#include <linux/netfilter_arp.h>
|
|
|
|
#include <linux/netfilter/x_tables.h>
|
|
|
|
#define ARPT_FUNCTION_MAXNAMELEN XT_FUNCTION_MAXNAMELEN
|
|
#define ARPT_TABLE_MAXNAMELEN XT_TABLE_MAXNAMELEN
|
|
#define arpt_target xt_target
|
|
#define arpt_table xt_table
|
|
|
|
#define ARPT_DEV_ADDR_LEN_MAX 16
|
|
|
|
struct arpt_devaddr_info {
|
|
char addr[ARPT_DEV_ADDR_LEN_MAX];
|
|
char mask[ARPT_DEV_ADDR_LEN_MAX];
|
|
};
|
|
|
|
/* Yes, Virginia, you have to zero the padding. */
|
|
struct arpt_arp {
|
|
/* Source and target IP addr */
|
|
struct in_addr src, tgt;
|
|
/* Mask for src and target IP addr */
|
|
struct in_addr smsk, tmsk;
|
|
|
|
/* Device hw address length, src+target device addresses */
|
|
u_int8_t arhln, arhln_mask;
|
|
struct arpt_devaddr_info src_devaddr;
|
|
struct arpt_devaddr_info tgt_devaddr;
|
|
|
|
/* ARP operation code. */
|
|
u_int16_t arpop, arpop_mask;
|
|
|
|
/* ARP hardware address and protocol address format. */
|
|
u_int16_t arhrd, arhrd_mask;
|
|
u_int16_t arpro, arpro_mask;
|
|
|
|
/* The protocol address length is only accepted if it is 4
|
|
* so there is no use in offering a way to do filtering on it.
|
|
*/
|
|
|
|
char iniface[IFNAMSIZ], outiface[IFNAMSIZ];
|
|
unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ];
|
|
|
|
/* Flags word */
|
|
u_int8_t flags;
|
|
/* Inverse flags */
|
|
u_int16_t invflags;
|
|
};
|
|
|
|
struct arpt_entry_target
|
|
{
|
|
union {
|
|
struct {
|
|
u_int16_t target_size;
|
|
|
|
/* Used by userspace */
|
|
char name[ARPT_FUNCTION_MAXNAMELEN-1];
|
|
u_int8_t revision;
|
|
} user;
|
|
struct {
|
|
u_int16_t target_size;
|
|
|
|
/* Used inside the kernel */
|
|
struct arpt_target *target;
|
|
} kernel;
|
|
|
|
/* Total length */
|
|
u_int16_t target_size;
|
|
} u;
|
|
|
|
unsigned char data[0];
|
|
};
|
|
|
|
struct arpt_standard_target
|
|
{
|
|
struct arpt_entry_target target;
|
|
int verdict;
|
|
};
|
|
|
|
/* Values for "flag" field in struct arpt_ip (general arp structure).
|
|
* No flags defined yet.
|
|
*/
|
|
#define ARPT_F_MASK 0x00 /* All possible flag bits mask. */
|
|
|
|
/* Values for "inv" field in struct arpt_arp. */
|
|
#define ARPT_INV_VIA_IN 0x0001 /* Invert the sense of IN IFACE. */
|
|
#define ARPT_INV_VIA_OUT 0x0002 /* Invert the sense of OUT IFACE */
|
|
#define ARPT_INV_SRCIP 0x0004 /* Invert the sense of SRC IP. */
|
|
#define ARPT_INV_TGTIP 0x0008 /* Invert the sense of TGT IP. */
|
|
#define ARPT_INV_SRCDEVADDR 0x0010 /* Invert the sense of SRC DEV ADDR. */
|
|
#define ARPT_INV_TGTDEVADDR 0x0020 /* Invert the sense of TGT DEV ADDR. */
|
|
#define ARPT_INV_ARPOP 0x0040 /* Invert the sense of ARP OP. */
|
|
#define ARPT_INV_ARPHRD 0x0080 /* Invert the sense of ARP HRD. */
|
|
#define ARPT_INV_ARPPRO 0x0100 /* Invert the sense of ARP PRO. */
|
|
#define ARPT_INV_ARPHLN 0x0200 /* Invert the sense of ARP HLN. */
|
|
#define ARPT_INV_MASK 0x03FF /* All possible flag bits mask. */
|
|
|
|
/* This structure defines each of the firewall rules. Consists of 3
|
|
parts which are 1) general ARP header stuff 2) match specific
|
|
stuff 3) the target to perform if the rule matches */
|
|
struct arpt_entry
|
|
{
|
|
struct arpt_arp arp;
|
|
|
|
/* Size of arpt_entry + matches */
|
|
u_int16_t target_offset;
|
|
/* Size of arpt_entry + matches + target */
|
|
u_int16_t next_offset;
|
|
|
|
/* Back pointer */
|
|
unsigned int comefrom;
|
|
|
|
/* Packet and byte counters. */
|
|
struct xt_counters counters;
|
|
|
|
/* The matches (if any), then the target. */
|
|
unsigned char elems[0];
|
|
};
|
|
|
|
/*
|
|
* New IP firewall options for [gs]etsockopt at the RAW IP level.
|
|
* Unlike BSD Linux inherits IP options so you don't have to use a raw
|
|
* socket for this. Instead we check rights in the calls.
|
|
*/
|
|
#define ARPT_CTL_OFFSET 32
|
|
#define ARPT_BASE_CTL (XT_BASE_CTL+ARPT_CTL_OFFSET)
|
|
|
|
#define ARPT_SO_SET_REPLACE (XT_SO_SET_REPLACE+ARPT_CTL_OFFSET)
|
|
#define ARPT_SO_SET_ADD_COUNTERS (XT_SO_SET_ADD_COUNTERS+ARPT_CTL_OFFSET)
|
|
#define ARPT_SO_SET_MAX (XT_SO_SET_MAX+ARPT_CTL_OFFSET)
|
|
|
|
#define ARPT_SO_GET_INFO (XT_SO_GET_INFO+ARPT_CTL_OFFSET)
|
|
#define ARPT_SO_GET_ENTRIES (XT_SO_GET_ENTRIES+ARPT_CTL_OFFSET)
|
|
/* #define ARPT_SO_GET_REVISION_MATCH XT_SO_GET_REVISION_MATCH */
|
|
#define ARPT_SO_GET_REVISION_TARGET (XT_SO_GET_REVISION_TARGET+ARPT_CTL_OFFSET)
|
|
#define ARPT_SO_GET_MAX (XT_SO_GET_REVISION_TARGET+ARPT_CTL_OFFSET)
|
|
|
|
/* CONTINUE verdict for targets */
|
|
#define ARPT_CONTINUE XT_CONTINUE
|
|
|
|
/* For standard target */
|
|
#define ARPT_RETURN XT_RETURN
|
|
|
|
/* The argument to ARPT_SO_GET_INFO */
|
|
struct arpt_getinfo
|
|
{
|
|
/* Which table: caller fills this in. */
|
|
char name[ARPT_TABLE_MAXNAMELEN];
|
|
|
|
/* Kernel fills these in. */
|
|
/* Which hook entry points are valid: bitmask */
|
|
unsigned int valid_hooks;
|
|
|
|
/* Hook entry points: one per netfilter hook. */
|
|
unsigned int hook_entry[NF_ARP_NUMHOOKS];
|
|
|
|
/* Underflow points. */
|
|
unsigned int underflow[NF_ARP_NUMHOOKS];
|
|
|
|
/* Number of entries */
|
|
unsigned int num_entries;
|
|
|
|
/* Size of entries. */
|
|
unsigned int size;
|
|
};
|
|
|
|
/* The argument to ARPT_SO_SET_REPLACE. */
|
|
struct arpt_replace
|
|
{
|
|
/* Which table. */
|
|
char name[ARPT_TABLE_MAXNAMELEN];
|
|
|
|
/* Which hook entry points are valid: bitmask. You can't
|
|
change this. */
|
|
unsigned int valid_hooks;
|
|
|
|
/* Number of entries */
|
|
unsigned int num_entries;
|
|
|
|
/* Total size of new entries */
|
|
unsigned int size;
|
|
|
|
/* Hook entry points. */
|
|
unsigned int hook_entry[NF_ARP_NUMHOOKS];
|
|
|
|
/* Underflow points. */
|
|
unsigned int underflow[NF_ARP_NUMHOOKS];
|
|
|
|
/* Information about old entries: */
|
|
/* Number of counters (must be equal to current number of entries). */
|
|
unsigned int num_counters;
|
|
/* The old entries' counters. */
|
|
struct xt_counters __user *counters;
|
|
|
|
/* The entries (hang off end: not really an array). */
|
|
struct arpt_entry entries[0];
|
|
};
|
|
|
|
/* The argument to ARPT_SO_ADD_COUNTERS. */
|
|
#define arpt_counters_info xt_counters_info
|
|
|
|
/* The argument to ARPT_SO_GET_ENTRIES. */
|
|
struct arpt_get_entries
|
|
{
|
|
/* Which table: user fills this in. */
|
|
char name[ARPT_TABLE_MAXNAMELEN];
|
|
|
|
/* User fills this in: total entry size. */
|
|
unsigned int size;
|
|
|
|
/* The entries. */
|
|
struct arpt_entry entrytable[0];
|
|
};
|
|
|
|
/* Standard return verdict, or do jump. */
|
|
#define ARPT_STANDARD_TARGET XT_STANDARD_TARGET
|
|
/* Error verdict. */
|
|
#define ARPT_ERROR_TARGET XT_ERROR_TARGET
|
|
|
|
/* Helper functions */
|
|
static __inline__ struct arpt_entry_target *arpt_get_target(struct arpt_entry *e)
|
|
{
|
|
return (void *)e + e->target_offset;
|
|
}
|
|
|
|
/* fn returns 0 to continue iteration */
|
|
#define ARPT_ENTRY_ITERATE(entries, size, fn, args...) \
|
|
({ \
|
|
unsigned int __i; \
|
|
int __ret = 0; \
|
|
struct arpt_entry *__entry; \
|
|
\
|
|
for (__i = 0; __i < (size); __i += __entry->next_offset) { \
|
|
__entry = (void *)(entries) + __i; \
|
|
\
|
|
__ret = fn(__entry , ## args); \
|
|
if (__ret != 0) \
|
|
break; \
|
|
} \
|
|
__ret; \
|
|
})
|
|
|
|
/*
|
|
* Main firewall chains definitions and global var's definitions.
|
|
*/
|
|
#ifdef __KERNEL__
|
|
|
|
#define arpt_register_target(tgt) xt_register_target(NF_ARP, tgt)
|
|
#define arpt_unregister_target(tgt) xt_unregister_target(NF_ARP, tgt)
|
|
|
|
extern int arpt_register_table(struct arpt_table *table,
|
|
const struct arpt_replace *repl);
|
|
extern void arpt_unregister_table(struct arpt_table *table);
|
|
extern unsigned int arpt_do_table(struct sk_buff **pskb,
|
|
unsigned int hook,
|
|
const struct net_device *in,
|
|
const struct net_device *out,
|
|
struct arpt_table *table,
|
|
void *userdata);
|
|
|
|
#define ARPT_ALIGN(s) (((s) + (__alignof__(struct arpt_entry)-1)) & ~(__alignof__(struct arpt_entry)-1))
|
|
#endif /*__KERNEL__*/
|
|
#endif /* _ARPTABLES_H */
|