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 38 struct 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. */ 44 struct 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 */ 96 struct 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 */ 135 struct 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. */ 157 struct 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. */ 188 struct 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 */ 200 static __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