[funini.com] -> [kei@sodan] -> Kernel Reading

root/include/linux/netfilter_arp/arp_tables.h

/* [<][>][^][v][top][bottom][index][help] */

INCLUDED FROM


DEFINITIONS

This source file includes following definitions.
  1. arpt_get_target
  2. compat_arpt_get_target

/*
 *      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/in.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>
#endif
#include <linux/types.h>
#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_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. */
        __be16 arpop, arpop_mask;

        /* ARP hardware address and protocol address format. */
        __be16 arhrd, arhrd_mask;
        __be16 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;
};

#define arpt_entry_target xt_entry_target
#define arpt_standard_target xt_standard_target

/* 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.
 *
 * ATTENTION: check linux/in.h before adding new number here.
 */
#define ARPT_BASE_CTL           96

#define ARPT_SO_SET_REPLACE             (ARPT_BASE_CTL)
#define ARPT_SO_SET_ADD_COUNTERS        (ARPT_BASE_CTL + 1)
#define ARPT_SO_SET_MAX                 ARPT_SO_SET_ADD_COUNTERS

#define ARPT_SO_GET_INFO                (ARPT_BASE_CTL)
#define ARPT_SO_GET_ENTRIES             (ARPT_BASE_CTL + 1)
/* #define ARPT_SO_GET_REVISION_MATCH   (APRT_BASE_CTL + 2) */
#define ARPT_SO_GET_REVISION_TARGET     (ARPT_BASE_CTL + 3)
#define ARPT_SO_GET_MAX                 (ARPT_SO_GET_REVISION_TARGET)

/* 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
#define arpt_counters xt_counters

/* 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...) \
        XT_ENTRY_ITERATE(struct arpt_entry, entries, size, fn, ## args)

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

/* Standard entry. */
struct arpt_standard
{
        struct arpt_entry entry;
        struct arpt_standard_target target;
};

struct arpt_error_target
{
        struct arpt_entry_target target;
        char errorname[ARPT_FUNCTION_MAXNAMELEN];
};

struct arpt_error
{
        struct arpt_entry entry;
        struct arpt_error_target target;
};

#define ARPT_ENTRY_INIT(__size)                                                \
{                                                                              \
        .target_offset  = sizeof(struct arpt_entry),                           \
        .next_offset    = (__size),                                            \
}

#define ARPT_STANDARD_INIT(__verdict)                                          \
{                                                                              \
        .entry          = ARPT_ENTRY_INIT(sizeof(struct arpt_standard)),       \
        .target         = XT_TARGET_INIT(ARPT_STANDARD_TARGET,                 \
                                         sizeof(struct arpt_standard_target)), \
        .target.verdict = -(__verdict) - 1,                                    \
}

#define ARPT_ERROR_INIT                                                        \
{                                                                              \
        .entry          = ARPT_ENTRY_INIT(sizeof(struct arpt_error)),          \
        .target         = XT_TARGET_INIT(ARPT_ERROR_TARGET,                    \
                                         sizeof(struct arpt_error_target)),    \
        .target.errorname = "ERROR",                                           \
}

extern struct xt_table *arpt_register_table(struct net *net,
                                            struct xt_table *table,
                                            const struct arpt_replace *repl);
extern void arpt_unregister_table(struct xt_table *table);
extern unsigned int arpt_do_table(struct sk_buff *skb,
                                  unsigned int hook,
                                  const struct net_device *in,
                                  const struct net_device *out,
                                  struct xt_table *table);

#define ARPT_ALIGN(s) XT_ALIGN(s)

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

struct compat_arpt_entry
{
        struct arpt_arp arp;
        u_int16_t target_offset;
        u_int16_t next_offset;
        compat_uint_t comefrom;
        struct compat_xt_counters counters;
        unsigned char elems[0];
};

static inline struct arpt_entry_target *
compat_arpt_get_target(struct compat_arpt_entry *e)
{
        return (void *)e + e->target_offset;
}

#define COMPAT_ARPT_ALIGN(s)    COMPAT_XT_ALIGN(s)

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

#define COMPAT_ARPT_ENTRY_ITERATE_CONTINUE(entries, size, n, fn, args...) \
        XT_ENTRY_ITERATE_CONTINUE(struct compat_arpt_entry, entries, size, n, \
                                  fn, ## args)

#endif /* CONFIG_COMPAT */
#endif /*__KERNEL__*/
#endif /* _ARPTABLES_H */

/* [<][>][^][v][top][bottom][index][help] */

[funini.com] -> [kei@sodan] -> Kernel Reading