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root/include/linux/netfilter_ipv4/ip_tables.h

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INCLUDED FROM


DEFINITIONS

This source file includes following definitions.
  1. ipt_get_target
  2. ipt_init
  3. compat_ipt_get_target

/*
 * 25-Jul-1998 Major changes to allow for ip chain table
 *
 * 3-Jan-2000 Named tables to allow packet selection for different uses.
 */

/*
 *      Format of an IP firewall descriptor
 *
 *      src, dst, src_mask, dst_mask are always stored in network byte order.
 *      flags are stored in host byte order (of course).
 *      Port numbers are stored in HOST byte order.
 */

#ifndef _IPTABLES_H
#define _IPTABLES_H

#ifdef __KERNEL__
#include <linux/if.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/skbuff.h>
#endif
#include <linux/types.h>
#include <linux/compiler.h>
#include <linux/netfilter_ipv4.h>

#include <linux/netfilter/x_tables.h>

#define IPT_FUNCTION_MAXNAMELEN XT_FUNCTION_MAXNAMELEN
#define IPT_TABLE_MAXNAMELEN XT_TABLE_MAXNAMELEN
#define ipt_match xt_match
#define ipt_target xt_target
#define ipt_table xt_table
#define ipt_get_revision xt_get_revision

/* Yes, Virginia, you have to zero the padding. */
struct ipt_ip {
        /* Source and destination IP addr */
        struct in_addr src, dst;
        /* Mask for src and dest IP addr */
        struct in_addr smsk, dmsk;
        char iniface[IFNAMSIZ], outiface[IFNAMSIZ];
        unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ];

        /* Protocol, 0 = ANY */
        u_int16_t proto;

        /* Flags word */
        u_int8_t flags;
        /* Inverse flags */
        u_int8_t invflags;
};

#define ipt_entry_match xt_entry_match
#define ipt_entry_target xt_entry_target
#define ipt_standard_target xt_standard_target

#define ipt_counters xt_counters

/* Values for "flag" field in struct ipt_ip (general ip structure). */
#define IPT_F_FRAG              0x01    /* Set if rule is a fragment rule */
#define IPT_F_GOTO              0x02    /* Set if jump is a goto */
#define IPT_F_MASK              0x03    /* All possible flag bits mask. */

/* Values for "inv" field in struct ipt_ip. */
#define IPT_INV_VIA_IN          0x01    /* Invert the sense of IN IFACE. */
#define IPT_INV_VIA_OUT         0x02    /* Invert the sense of OUT IFACE */
#define IPT_INV_TOS             0x04    /* Invert the sense of TOS. */
#define IPT_INV_SRCIP           0x08    /* Invert the sense of SRC IP. */
#define IPT_INV_DSTIP           0x10    /* Invert the sense of DST OP. */
#define IPT_INV_FRAG            0x20    /* Invert the sense of FRAG. */
#define IPT_INV_PROTO           XT_INV_PROTO
#define IPT_INV_MASK            0x7F    /* All possible flag bits mask. */

/* This structure defines each of the firewall rules.  Consists of 3
   parts which are 1) general IP header stuff 2) match specific
   stuff 3) the target to perform if the rule matches */
struct ipt_entry
{
        struct ipt_ip ip;

        /* Mark with fields that we care about. */
        unsigned int nfcache;

        /* Size of ipt_entry + matches */
        u_int16_t target_offset;
        /* Size of ipt_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.
 *
 * ATTENTION: check linux/in.h before adding new number here.
 */
#define IPT_BASE_CTL            64

#define IPT_SO_SET_REPLACE      (IPT_BASE_CTL)
#define IPT_SO_SET_ADD_COUNTERS (IPT_BASE_CTL + 1)
#define IPT_SO_SET_MAX          IPT_SO_SET_ADD_COUNTERS

#define IPT_SO_GET_INFO                 (IPT_BASE_CTL)
#define IPT_SO_GET_ENTRIES              (IPT_BASE_CTL + 1)
#define IPT_SO_GET_REVISION_MATCH       (IPT_BASE_CTL + 2)
#define IPT_SO_GET_REVISION_TARGET      (IPT_BASE_CTL + 3)
#define IPT_SO_GET_MAX                  IPT_SO_GET_REVISION_TARGET

#define IPT_CONTINUE XT_CONTINUE
#define IPT_RETURN XT_RETURN

#include <linux/netfilter/xt_tcpudp.h>
#define ipt_udp xt_udp
#define ipt_tcp xt_tcp

#define IPT_TCP_INV_SRCPT       XT_TCP_INV_SRCPT
#define IPT_TCP_INV_DSTPT       XT_TCP_INV_DSTPT
#define IPT_TCP_INV_FLAGS       XT_TCP_INV_FLAGS
#define IPT_TCP_INV_OPTION      XT_TCP_INV_OPTION
#define IPT_TCP_INV_MASK        XT_TCP_INV_MASK

#define IPT_UDP_INV_SRCPT       XT_UDP_INV_SRCPT
#define IPT_UDP_INV_DSTPT       XT_UDP_INV_DSTPT
#define IPT_UDP_INV_MASK        XT_UDP_INV_MASK

/* ICMP matching stuff */
struct ipt_icmp
{
        u_int8_t type;                          /* type to match */
        u_int8_t code[2];                       /* range of code */
        u_int8_t invflags;                      /* Inverse flags */
};

/* Values for "inv" field for struct ipt_icmp. */
#define IPT_ICMP_INV    0x01    /* Invert the sense of type/code test */

/* The argument to IPT_SO_GET_INFO */
struct ipt_getinfo
{
        /* Which table: caller fills this in. */
        char name[IPT_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_INET_NUMHOOKS];

        /* Underflow points. */
        unsigned int underflow[NF_INET_NUMHOOKS];

        /* Number of entries */
        unsigned int num_entries;

        /* Size of entries. */
        unsigned int size;
};

/* The argument to IPT_SO_SET_REPLACE. */
struct ipt_replace
{
        /* Which table. */
        char name[IPT_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_INET_NUMHOOKS];

        /* Underflow points. */
        unsigned int underflow[NF_INET_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 ipt_entry entries[0];
};

/* The argument to IPT_SO_ADD_COUNTERS. */
#define ipt_counters_info xt_counters_info

/* The argument to IPT_SO_GET_ENTRIES. */
struct ipt_get_entries
{
        /* Which table: user fills this in. */
        char name[IPT_TABLE_MAXNAMELEN];

        /* User fills this in: total entry size. */
        unsigned int size;

        /* The entries. */
        struct ipt_entry entrytable[0];
};

/* Standard return verdict, or do jump. */
#define IPT_STANDARD_TARGET XT_STANDARD_TARGET
/* Error verdict. */
#define IPT_ERROR_TARGET XT_ERROR_TARGET

/* Helper functions */
static __inline__ struct ipt_entry_target *
ipt_get_target(struct ipt_entry *e)
{
        return (void *)e + e->target_offset;
}

/* fn returns 0 to continue iteration */
#define IPT_MATCH_ITERATE(e, fn, args...) \
        XT_MATCH_ITERATE(struct ipt_entry, e, fn, ## args)

/* fn returns 0 to continue iteration */
#define IPT_ENTRY_ITERATE(entries, size, fn, args...) \
        XT_ENTRY_ITERATE(struct ipt_entry, entries, size, fn, ## args)

/*
 *      Main firewall chains definitions and global var's definitions.
 */
#ifdef __KERNEL__

#include <linux/init.h>
extern void ipt_init(void) __init;

extern struct xt_table *ipt_register_table(struct net *net,
                                           struct xt_table *table,
                                           const struct ipt_replace *repl);
extern void ipt_unregister_table(struct xt_table *table);

/* Standard entry. */
struct ipt_standard
{
        struct ipt_entry entry;
        struct ipt_standard_target target;
};

struct ipt_error_target
{
        struct ipt_entry_target target;
        char errorname[IPT_FUNCTION_MAXNAMELEN];
};

struct ipt_error
{
        struct ipt_entry entry;
        struct ipt_error_target target;
};

#define IPT_ENTRY_INIT(__size)                                                 \
{                                                                              \
        .target_offset  = sizeof(struct ipt_entry),                            \
        .next_offset    = (__size),                                            \
}

#define IPT_STANDARD_INIT(__verdict)                                           \
{                                                                              \
        .entry          = IPT_ENTRY_INIT(sizeof(struct ipt_standard)),         \
        .target         = XT_TARGET_INIT(IPT_STANDARD_TARGET,                  \
                                         sizeof(struct xt_standard_target)),   \
        .target.verdict = -(__verdict) - 1,                                    \
}

#define IPT_ERROR_INIT                                                         \
{                                                                              \
        .entry          = IPT_ENTRY_INIT(sizeof(struct ipt_error)),            \
        .target         = XT_TARGET_INIT(IPT_ERROR_TARGET,                     \
                                         sizeof(struct ipt_error_target)),     \
        .target.errorname = "ERROR",                                           \
}

extern unsigned int ipt_do_table(struct sk_buff *skb,
                                 unsigned int hook,
                                 const struct net_device *in,
                                 const struct net_device *out,
                                 struct xt_table *table);

#define IPT_ALIGN(s) XT_ALIGN(s)

#ifdef CONFIG_COMPAT
#include <net/compat.h>

struct compat_ipt_entry
{
        struct ipt_ip ip;
        compat_uint_t nfcache;
        u_int16_t target_offset;
        u_int16_t next_offset;
        compat_uint_t comefrom;
        struct compat_xt_counters counters;
        unsigned char elems[0];
};

/* Helper functions */
static inline struct ipt_entry_target *
compat_ipt_get_target(struct compat_ipt_entry *e)
{
        return (void *)e + e->target_offset;
}

#define COMPAT_IPT_ALIGN(s)     COMPAT_XT_ALIGN(s)

/* fn returns 0 to continue iteration */
#define COMPAT_IPT_MATCH_ITERATE(e, fn, args...) \
        XT_MATCH_ITERATE(struct compat_ipt_entry, e, fn, ## args)

/* fn returns 0 to continue iteration */
#define COMPAT_IPT_ENTRY_ITERATE(entries, size, fn, args...) \
        XT_ENTRY_ITERATE(struct compat_ipt_entry, entries, size, fn, ## args)

/* fn returns 0 to continue iteration */
#define COMPAT_IPT_ENTRY_ITERATE_CONTINUE(entries, size, n, fn, args...) \
        XT_ENTRY_ITERATE_CONTINUE(struct compat_ipt_entry, entries, size, n, \
                                  fn, ## args)

#endif /* CONFIG_COMPAT */
#endif /*__KERNEL__*/
#endif /* _IPTABLES_H */

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