LXR linux/include/uapi/linux/netfilter_arp/arp

   1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
   2/*
   3 *      Format of an ARP firewall descriptor
   4 *
   5 *      src, tgt, src_mask, tgt_mask, arpop, arpop_mask are always stored in
   6 *      network byte order.
   7 *      flags are stored in host byte order (of course).
   8 */
   9
  10#ifndef _UAPI_ARPTABLES_H
  11#define _UAPI_ARPTABLES_H
  12
  13#include <linux/types.h>
  14#include <linux/compiler.h>
  15#include <linux/if.h>
  16#include <linux/netfilter_arp.h>
  17
  18#include <linux/netfilter/x_tables.h>
  19
  20#ifndef __KERNEL__
  21#define ARPT_FUNCTION_MAXNAMELEN XT_FUNCTION_MAXNAMELEN
  22#define ARPT_TABLE_MAXNAMELEN XT_TABLE_MAXNAMELEN
  23#define arpt_entry_target xt_entry_target
  24#define arpt_standard_target xt_standard_target
  25#define arpt_error_target xt_error_target
  26#define ARPT_CONTINUE XT_CONTINUE
  27#define ARPT_RETURN XT_RETURN
  28#define arpt_counters_info xt_counters_info
  29#define arpt_counters xt_counters
  30#define ARPT_STANDARD_TARGET XT_STANDARD_TARGET
  31#define ARPT_ERROR_TARGET XT_ERROR_TARGET
  32#define ARPT_ENTRY_ITERATE(entries, size, fn, args...) \
  33        XT_ENTRY_ITERATE(struct arpt_entry, entries, size, fn, ## args)
  34#endif
  35
  36#define ARPT_DEV_ADDR_LEN_MAX 16
  37
  38struct arpt_devaddr_info {
  39        char addr[ARPT_DEV_ADDR_LEN_MAX];
  40        char mask[ARPT_DEV_ADDR_LEN_MAX];
  41};
  42
  43/* Yes, Virginia, you have to zero the padding. */
  44struct arpt_arp {
  45        /* Source and target IP addr */
  46        struct in_addr src, tgt;
  47        /* Mask for src and target IP addr */
  48        struct in_addr smsk, tmsk;
  49
  50        /* Device hw address length, src+target device addresses */
  51        __u8 arhln, arhln_mask;
  52        struct arpt_devaddr_info src_devaddr;
  53        struct arpt_devaddr_info tgt_devaddr;
  54
  55        /* ARP operation code. */
  56        __be16 arpop, arpop_mask;
  57
  58        /* ARP hardware address and protocol address format. */
  59        __be16 arhrd, arhrd_mask;
  60        __be16 arpro, arpro_mask;
  61
  62        /* The protocol address length is only accepted if it is 4
  63         * so there is no use in offering a way to do filtering on it.
  64         */
  65
  66        char iniface[IFNAMSIZ], outiface[IFNAMSIZ];
  67        unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ];
  68
  69        /* Flags word */
  70        __u8 flags;
  71        /* Inverse flags */
  72        __u16 invflags;
  73};
  74
  75/* Values for "flag" field in struct arpt_ip (general arp structure).
  76 * No flags defined yet.
  77 */
  78#define ARPT_F_MASK             0x00    /* All possible flag bits mask. */
  79
  80/* Values for "inv" field in struct arpt_arp. */
  81#define ARPT_INV_VIA_IN         0x0001  /* Invert the sense of IN IFACE. */
  82#define ARPT_INV_VIA_OUT        0x0002  /* Invert the sense of OUT IFACE */
  83#define ARPT_INV_SRCIP          0x0004  /* Invert the sense of SRC IP. */
  84#define ARPT_INV_TGTIP          0x0008  /* Invert the sense of TGT IP. */
  85#define ARPT_INV_SRCDEVADDR     0x0010  /* Invert the sense of SRC DEV ADDR. */
  86#define ARPT_INV_TGTDEVADDR     0x0020  /* Invert the sense of TGT DEV ADDR. */
  87#define ARPT_INV_ARPOP          0x0040  /* Invert the sense of ARP OP. */
  88#define ARPT_INV_ARPHRD         0x0080  /* Invert the sense of ARP HRD. */
  89#define ARPT_INV_ARPPRO         0x0100  /* Invert the sense of ARP PRO. */
  90#define ARPT_INV_ARPHLN         0x0200  /* Invert the sense of ARP HLN. */
  91#define ARPT_INV_MASK           0x03FF  /* All possible flag bits mask. */
  92
  93/* This structure defines each of the firewall rules.  Consists of 3
  94   parts which are 1) general ARP header stuff 2) match specific
  95   stuff 3) the target to perform if the rule matches */
  96struct arpt_entry
  97{
  98        struct arpt_arp arp;
  99
 100        /* Size of arpt_entry + matches */
 101        __u16 target_offset;
 102        /* Size of arpt_entry + matches + target */
 103        __u16 next_offset;
 104
 105        /* Back pointer */
 106        unsigned int comefrom;
 107
 108        /* Packet and byte counters. */
 109        struct xt_counters counters;
 110
 111        /* The matches (if any), then the target. */
 112        unsigned char elems[0];
 113};
 114
 115/*
 116 * New IP firewall options for [gs]etsockopt at the RAW IP level.
 117 * Unlike BSD Linux inherits IP options so you don't have to use a raw
 118 * socket for this. Instead we check rights in the calls.
 119 *
 120 * ATTENTION: check linux/in.h before adding new number here.
 121 */
 122#define ARPT_BASE_CTL           96
 123
 124#define ARPT_SO_SET_REPLACE             (ARPT_BASE_CTL)
 125#define ARPT_SO_SET_ADD_COUNTERS        (ARPT_BASE_CTL + 1)
 126#define ARPT_SO_SET_MAX                 ARPT_SO_SET_ADD_COUNTERS
 127
 128#define ARPT_SO_GET_INFO                (ARPT_BASE_CTL)
 129#define ARPT_SO_GET_ENTRIES             (ARPT_BASE_CTL + 1)
 130/* #define ARPT_SO_GET_REVISION_MATCH   (APRT_BASE_CTL + 2) */
 131#define ARPT_SO_GET_REVISION_TARGET     (ARPT_BASE_CTL + 3)
 132#define ARPT_SO_GET_MAX                 (ARPT_SO_GET_REVISION_TARGET)
 133
 134/* The argument to ARPT_SO_GET_INFO */
 135struct arpt_getinfo {
 136        /* Which table: caller fills this in. */
 137        char name[XT_TABLE_MAXNAMELEN];
 138
 139        /* Kernel fills these in. */
 140        /* Which hook entry points are valid: bitmask */
 141        unsigned int valid_hooks;
 142
 143        /* Hook entry points: one per netfilter hook. */
 144        unsigned int hook_entry[NF_ARP_NUMHOOKS];
 145
 146        /* Underflow points. */
 147        unsigned int underflow[NF_ARP_NUMHOOKS];
 148
 149        /* Number of entries */
 150        unsigned int num_entries;
 151
 152        /* Size of entries. */
 153        unsigned int size;
 154};
 155
 156/* The argument to ARPT_SO_SET_REPLACE. */
 157struct arpt_replace {
 158        /* Which table. */
 159        char name[XT_TABLE_MAXNAMELEN];
 160
 161        /* Which hook entry points are valid: bitmask.  You can't
 162           change this. */
 163        unsigned int valid_hooks;
 164
 165        /* Number of entries */
 166        unsigned int num_entries;
 167
 168        /* Total size of new entries */
 169        unsigned int size;
 170
 171        /* Hook entry points. */
 172        unsigned int hook_entry[NF_ARP_NUMHOOKS];
 173
 174        /* Underflow points. */
 175        unsigned int underflow[NF_ARP_NUMHOOKS];
 176
 177        /* Information about old entries: */
 178        /* Number of counters (must be equal to current number of entries). */
 179        unsigned int num_counters;
 180        /* The old entries' counters. */
 181        struct xt_counters __user *counters;
 182
 183        /* The entries (hang off end: not really an array). */
 184        struct arpt_entry entries[0];
 185};
 186
 187/* The argument to ARPT_SO_GET_ENTRIES. */
 188struct arpt_get_entries {
 189        /* Which table: user fills this in. */
 190        char name[XT_TABLE_MAXNAMELEN];
 191
 192        /* User fills this in: total entry size. */
 193        unsigned int size;
 194
 195        /* The entries. */
 196        struct arpt_entry entrytable[0];
 197};
 198
 199/* Helper functions */
 200static __inline__ struct xt_entry_target *arpt_get_target(struct arpt_entry *e)
 201{
 202        return (struct xt_entry_target *)((char *)e + e->target_offset);
 203}
 204
 205/*
 206 *      Main firewall chains definitions and global var's definitions.
 207 */
 208#endif /* _UAPI_ARPTABLES_H */
 209