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