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      1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
      2 /*
      3  * 25-Jul-1998 Major changes to allow for ip chain table
      4  *
      5  * 3-Jan-2000 Named tables to allow packet selection for different uses.
      6  */
      7 
      8 /*
      9  * 	Format of an IP firewall descriptor
     10  *
     11  * 	src, dst, src_mask, dst_mask are always stored in network byte order.
     12  * 	flags are stored in host byte order (of course).
     13  * 	Port numbers are stored in HOST byte order.
     14  */
     15 
     16 #ifndef _UAPI_IPTABLES_H
     17 #define _UAPI_IPTABLES_H
     18 
     19 #include <linux/types.h>
     20 #include <linux/compiler.h>
     21 #include <linux/if.h>
     22 #include <linux/netfilter_ipv4.h>
     23 
     24 #include <linux/netfilter/x_tables.h>
     25 
     26 #ifndef __KERNEL__
     27 #define IPT_FUNCTION_MAXNAMELEN XT_FUNCTION_MAXNAMELEN
     28 #define IPT_TABLE_MAXNAMELEN XT_TABLE_MAXNAMELEN
     29 #define ipt_match xt_match
     30 #define ipt_target xt_target
     31 #define ipt_table xt_table
     32 #define ipt_get_revision xt_get_revision
     33 #define ipt_entry_match xt_entry_match
     34 #define ipt_entry_target xt_entry_target
     35 #define ipt_standard_target xt_standard_target
     36 #define ipt_error_target xt_error_target
     37 #define ipt_counters xt_counters
     38 #define IPT_CONTINUE XT_CONTINUE
     39 #define IPT_RETURN XT_RETURN
     40 
     41 /* This group is older than old (iptables < v1.4.0-rc1~89) */
     42 #include <linux/netfilter/xt_tcpudp.h>
     43 #define ipt_udp xt_udp
     44 #define ipt_tcp xt_tcp
     45 #define IPT_TCP_INV_SRCPT	XT_TCP_INV_SRCPT
     46 #define IPT_TCP_INV_DSTPT	XT_TCP_INV_DSTPT
     47 #define IPT_TCP_INV_FLAGS	XT_TCP_INV_FLAGS
     48 #define IPT_TCP_INV_OPTION	XT_TCP_INV_OPTION
     49 #define IPT_TCP_INV_MASK	XT_TCP_INV_MASK
     50 #define IPT_UDP_INV_SRCPT	XT_UDP_INV_SRCPT
     51 #define IPT_UDP_INV_DSTPT	XT_UDP_INV_DSTPT
     52 #define IPT_UDP_INV_MASK	XT_UDP_INV_MASK
     53 
     54 /* The argument to IPT_SO_ADD_COUNTERS. */
     55 #define ipt_counters_info xt_counters_info
     56 /* Standard return verdict, or do jump. */
     57 #define IPT_STANDARD_TARGET XT_STANDARD_TARGET
     58 /* Error verdict. */
     59 #define IPT_ERROR_TARGET XT_ERROR_TARGET
     60 
     61 /* fn returns 0 to continue iteration */
     62 #define IPT_MATCH_ITERATE(e, fn, args...) \
     63 	XT_MATCH_ITERATE(struct ipt_entry, e, fn, ## args)
     64 
     65 /* fn returns 0 to continue iteration */
     66 #define IPT_ENTRY_ITERATE(entries, size, fn, args...) \
     67 	XT_ENTRY_ITERATE(struct ipt_entry, entries, size, fn, ## args)
     68 #endif
     69 
     70 /* Yes, Virginia, you have to zero the padding. */
     71 struct ipt_ip {
     72 	/* Source and destination IP addr */
     73 	struct in_addr src, dst;
     74 	/* Mask for src and dest IP addr */
     75 	struct in_addr smsk, dmsk;
     76 	char iniface[IFNAMSIZ], outiface[IFNAMSIZ];
     77 	unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ];
     78 
     79 	/* Protocol, 0 = ANY */
     80 	__u16 proto;
     81 
     82 	/* Flags word */
     83 	__u8 flags;
     84 	/* Inverse flags */
     85 	__u8 invflags;
     86 };
     87 
     88 /* Values for "flag" field in struct ipt_ip (general ip structure). */
     89 #define IPT_F_FRAG		0x01	/* Set if rule is a fragment rule */
     90 #define IPT_F_GOTO		0x02	/* Set if jump is a goto */
     91 #define IPT_F_MASK		0x03	/* All possible flag bits mask. */
     92 
     93 /* Values for "inv" field in struct ipt_ip. */
     94 #define IPT_INV_VIA_IN		0x01	/* Invert the sense of IN IFACE. */
     95 #define IPT_INV_VIA_OUT		0x02	/* Invert the sense of OUT IFACE */
     96 #define IPT_INV_TOS		0x04	/* Invert the sense of TOS. */
     97 #define IPT_INV_SRCIP		0x08	/* Invert the sense of SRC IP. */
     98 #define IPT_INV_DSTIP		0x10	/* Invert the sense of DST OP. */
     99 #define IPT_INV_FRAG		0x20	/* Invert the sense of FRAG. */
    100 #define IPT_INV_PROTO		XT_INV_PROTO
    101 #define IPT_INV_MASK		0x7F	/* All possible flag bits mask. */
    102 
    103 /* This structure defines each of the firewall rules.  Consists of 3
    104    parts which are 1) general IP header stuff 2) match specific
    105    stuff 3) the target to perform if the rule matches */
    106 struct ipt_entry {
    107 	struct ipt_ip ip;
    108 
    109 	/* Mark with fields that we care about. */
    110 	unsigned int nfcache;
    111 
    112 	/* Size of ipt_entry + matches */
    113 	__u16 target_offset;
    114 	/* Size of ipt_entry + matches + target */
    115 	__u16 next_offset;
    116 
    117 	/* Back pointer */
    118 	unsigned int comefrom;
    119 
    120 	/* Packet and byte counters. */
    121 	struct xt_counters counters;
    122 
    123 	/* The matches (if any), then the target. */
    124 	unsigned char elems[0];
    125 };
    126 
    127 /*
    128  * New IP firewall options for [gs]etsockopt at the RAW IP level.
    129  * Unlike BSD Linux inherits IP options so you don't have to use a raw
    130  * socket for this. Instead we check rights in the calls.
    131  *
    132  * ATTENTION: check linux/in.h before adding new number here.
    133  */
    134 #define IPT_BASE_CTL		64
    135 
    136 #define IPT_SO_SET_REPLACE	(IPT_BASE_CTL)
    137 #define IPT_SO_SET_ADD_COUNTERS	(IPT_BASE_CTL + 1)
    138 #define IPT_SO_SET_MAX		IPT_SO_SET_ADD_COUNTERS
    139 
    140 #define IPT_SO_GET_INFO			(IPT_BASE_CTL)
    141 #define IPT_SO_GET_ENTRIES		(IPT_BASE_CTL + 1)
    142 #define IPT_SO_GET_REVISION_MATCH	(IPT_BASE_CTL + 2)
    143 #define IPT_SO_GET_REVISION_TARGET	(IPT_BASE_CTL + 3)
    144 #define IPT_SO_GET_MAX			IPT_SO_GET_REVISION_TARGET
    145 
    146 /* ICMP matching stuff */
    147 struct ipt_icmp {
    148 	__u8 type;				/* type to match */
    149 	__u8 code[2];				/* range of code */
    150 	__u8 invflags;				/* Inverse flags */
    151 };
    152 
    153 /* Values for "inv" field for struct ipt_icmp. */
    154 #define IPT_ICMP_INV	0x01	/* Invert the sense of type/code test */
    155 
    156 /* The argument to IPT_SO_GET_INFO */
    157 struct ipt_getinfo {
    158 	/* Which table: caller fills this in. */
    159 	char name[XT_TABLE_MAXNAMELEN];
    160 
    161 	/* Kernel fills these in. */
    162 	/* Which hook entry points are valid: bitmask */
    163 	unsigned int valid_hooks;
    164 
    165 	/* Hook entry points: one per netfilter hook. */
    166 	unsigned int hook_entry[NF_INET_NUMHOOKS];
    167 
    168 	/* Underflow points. */
    169 	unsigned int underflow[NF_INET_NUMHOOKS];
    170 
    171 	/* Number of entries */
    172 	unsigned int num_entries;
    173 
    174 	/* Size of entries. */
    175 	unsigned int size;
    176 };
    177 
    178 /* The argument to IPT_SO_SET_REPLACE. */
    179 struct ipt_replace {
    180 	/* Which table. */
    181 	char name[XT_TABLE_MAXNAMELEN];
    182 
    183 	/* Which hook entry points are valid: bitmask.  You can't
    184            change this. */
    185 	unsigned int valid_hooks;
    186 
    187 	/* Number of entries */
    188 	unsigned int num_entries;
    189 
    190 	/* Total size of new entries */
    191 	unsigned int size;
    192 
    193 	/* Hook entry points. */
    194 	unsigned int hook_entry[NF_INET_NUMHOOKS];
    195 
    196 	/* Underflow points. */
    197 	unsigned int underflow[NF_INET_NUMHOOKS];
    198 
    199 	/* Information about old entries: */
    200 	/* Number of counters (must be equal to current number of entries). */
    201 	unsigned int num_counters;
    202 	/* The old entries' counters. */
    203 	struct xt_counters __user *counters;
    204 
    205 	/* The entries (hang off end: not really an array). */
    206 	struct ipt_entry entries[0];
    207 };
    208 
    209 /* The argument to IPT_SO_GET_ENTRIES. */
    210 struct ipt_get_entries {
    211 	/* Which table: user fills this in. */
    212 	char name[XT_TABLE_MAXNAMELEN];
    213 
    214 	/* User fills this in: total entry size. */
    215 	unsigned int size;
    216 
    217 	/* The entries. */
    218 	struct ipt_entry entrytable[0];
    219 };
    220 
    221 /* Helper functions */
    222 static __inline__ struct xt_entry_target *
    223 ipt_get_target(struct ipt_entry *e)
    224 {
    225 	return (void *)e + e->target_offset;
    226 }
    227 
    228 /*
    229  *	Main firewall chains definitions and global var's definitions.
    230  */
    231 #endif /* _UAPI_IPTABLES_H */
    232