ip6_tables.h

Go to the documentation of this file.

/*
 * 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 IP6 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 _UAPI_IP6_TABLES_H
#define _UAPI_IP6_TABLES_H

#include <linux/types.h>
#include <linux/compiler.h>
#include <linux/netfilter_ipv6.h>

#include <linux/netfilter/x_tables.h>

#ifndef __KERNEL__
#define IP6T_FUNCTION_MAXNAMELEN XT_FUNCTION_MAXNAMELEN
#define IP6T_TABLE_MAXNAMELEN XT_TABLE_MAXNAMELEN
#define ip6t_match xt_match
#define ip6t_target xt_target
#define ip6t_table xt_table
#define ip6t_get_revision xt_get_revision
#define ip6t_entry_match xt_entry_match
#define ip6t_entry_target xt_entry_target
#define ip6t_standard_target xt_standard_target
#define ip6t_error_target xt_error_target
#define ip6t_counters xt_counters
#define IP6T_CONTINUE XT_CONTINUE
#define IP6T_RETURN XT_RETURN

/* Pre-iptables-1.4.0 */
#include <linux/netfilter/xt_tcpudp.h>
#define ip6t_tcp xt_tcp
#define ip6t_udp xt_udp
#define IP6T_TCP_INV_SRCPT  XT_TCP_INV_SRCPT
#define IP6T_TCP_INV_DSTPT  XT_TCP_INV_DSTPT
#define IP6T_TCP_INV_FLAGS  XT_TCP_INV_FLAGS
#define IP6T_TCP_INV_OPTION XT_TCP_INV_OPTION
#define IP6T_TCP_INV_MASK   XT_TCP_INV_MASK
#define IP6T_UDP_INV_SRCPT  XT_UDP_INV_SRCPT
#define IP6T_UDP_INV_DSTPT  XT_UDP_INV_DSTPT
#define IP6T_UDP_INV_MASK   XT_UDP_INV_MASK

#define ip6t_counters_info xt_counters_info
#define IP6T_STANDARD_TARGET XT_STANDARD_TARGET
#define IP6T_ERROR_TARGET XT_ERROR_TARGET
#define IP6T_MATCH_ITERATE(e, fn, args...) \
    XT_MATCH_ITERATE(struct ip6t_entry, e, fn, ## args)
#define IP6T_ENTRY_ITERATE(entries, size, fn, args...) \
    XT_ENTRY_ITERATE(struct ip6t_entry, entries, size, fn, ## args)
#endif

/* Yes, Virginia, you have to zero the padding. */
struct ip6t_ip6 {
    /* Source and destination IP6 addr */
    struct in6_addr src, dst;       
    /* Mask for src and dest IP6 addr */
    struct in6_addr smsk, dmsk;
    char iniface[IFNAMSIZ], outiface[IFNAMSIZ];
    unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ];

    /* Upper protocol number
     * - The allowed value is 0 (any) or protocol number of last parsable
     *   header, which is 50 (ESP), 59 (No Next Header), 135 (MH), or
     *   the non IPv6 extension headers.
     * - The protocol numbers of IPv6 extension headers except of ESP and
     *   MH do not match any packets.
     * - You also need to set IP6T_FLAGS_PROTO to "flags" to check protocol.
     */
    __u16 proto;
    /* TOS to match iff flags & IP6T_F_TOS */
    __u8 tos;

    /* Flags word */
    __u8 flags;
    /* Inverse flags */
    __u8 invflags;
};

/* Values for "flag" field in struct ip6t_ip6 (general ip6 structure). */
#define IP6T_F_PROTO        0x01    /* Set if rule cares about upper 
                       protocols */
#define IP6T_F_TOS      0x02    /* Match the TOS. */
#define IP6T_F_GOTO     0x04    /* Set if jump is a goto */
#define IP6T_F_MASK     0x07    /* All possible flag bits mask. */

/* Values for "inv" field in struct ip6t_ip6. */
#define IP6T_INV_VIA_IN     0x01    /* Invert the sense of IN IFACE. */
#define IP6T_INV_VIA_OUT        0x02    /* Invert the sense of OUT IFACE */
#define IP6T_INV_TOS        0x04    /* Invert the sense of TOS. */
#define IP6T_INV_SRCIP      0x08    /* Invert the sense of SRC IP. */
#define IP6T_INV_DSTIP      0x10    /* Invert the sense of DST OP. */
#define IP6T_INV_FRAG       0x20    /* Invert the sense of FRAG. */
#define IP6T_INV_PROTO      XT_INV_PROTO
#define IP6T_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 ip6t_entry {
    struct ip6t_ip6 ipv6;

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

    /* Size of ipt_entry + matches */
    __u16 target_offset;
    /* Size of ipt_entry + matches + target */
    __u16 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];
};

/* Standard entry */
struct ip6t_standard {
    struct ip6t_entry entry;
    struct xt_standard_target target;
};

struct ip6t_error {
    struct ip6t_entry entry;
    struct xt_error_target target;
};

#define IP6T_ENTRY_INIT(__size)                            \
{                                          \
    .target_offset  = sizeof(struct ip6t_entry),                   \
    .next_offset    = (__size),                        \
}

#define IP6T_STANDARD_INIT(__verdict)                          \
{                                          \
    .entry      = IP6T_ENTRY_INIT(sizeof(struct ip6t_standard)),       \
    .target     = XT_TARGET_INIT(XT_STANDARD_TARGET,               \
                     sizeof(struct xt_standard_target)),   \
    .target.verdict = -(__verdict) - 1,                    \
}

#define IP6T_ERROR_INIT                                \
{                                          \
    .entry      = IP6T_ENTRY_INIT(sizeof(struct ip6t_error)),          \
    .target     = XT_TARGET_INIT(XT_ERROR_TARGET,              \
                     sizeof(struct xt_error_target)),      \
    .target.errorname = "ERROR",                           \
}

/*
 * 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/in6.h before adding new number here.
 */
#define IP6T_BASE_CTL           64

#define IP6T_SO_SET_REPLACE     (IP6T_BASE_CTL)
#define IP6T_SO_SET_ADD_COUNTERS    (IP6T_BASE_CTL + 1)
#define IP6T_SO_SET_MAX         IP6T_SO_SET_ADD_COUNTERS

#define IP6T_SO_GET_INFO        (IP6T_BASE_CTL)
#define IP6T_SO_GET_ENTRIES     (IP6T_BASE_CTL + 1)
#define IP6T_SO_GET_REVISION_MATCH  (IP6T_BASE_CTL + 4)
#define IP6T_SO_GET_REVISION_TARGET (IP6T_BASE_CTL + 5)
#define IP6T_SO_GET_MAX         IP6T_SO_GET_REVISION_TARGET

/* ICMP matching stuff */
struct ip6t_icmp {
    __u8 type;              /* type to match */
    __u8 code[2];               /* range of code */
    __u8 invflags;              /* Inverse flags */
};

/* Values for "inv" field for struct ipt_icmp. */
#define IP6T_ICMP_INV   0x01    /* Invert the sense of type/code test */

/* The argument to IP6T_SO_GET_INFO */
struct ip6t_getinfo {
    /* Which table: caller fills this in. */
    char name[XT_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 IP6T_SO_SET_REPLACE. */
struct ip6t_replace {
    /* Which table. */
    char name[XT_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 ip6t_entry entries[0];
};

/* The argument to IP6T_SO_GET_ENTRIES. */
struct ip6t_get_entries {
    /* Which table: user fills this in. */
    char name[XT_TABLE_MAXNAMELEN];

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

    /* The entries. */
    struct ip6t_entry entrytable[0];
};

/* Helper functions */
static __inline__ struct xt_entry_target *
ip6t_get_target(struct ip6t_entry *e)
{
    return (void *)e + e->target_offset;
}

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

#endif /* _UAPI_IP6_TABLES_H */