include/uapi/linux/netfilter_arp/arp_tables.h

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