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[];
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[];
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[];
219 };
220 
221 /* Helper functions */
222 static __inline__ struct xt_entry_target *
ipt_get_target(struct ipt_entry * e)223 ipt_get_target(struct ipt_entry *e)
224 {
225 	return (struct xt_entry_target *)((char *)e + e->target_offset);
226 }
227 
228 /*
229  *	Main firewall chains definitions and global var's definitions.
230  */
231 #endif /* _UAPI_IPTABLES_H */
232