Commit | Line | Data |
---|---|---|
1da177e4 LT |
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 _ARPTABLES_H | |
10 | #define _ARPTABLES_H | |
11 | ||
12 | #ifdef __KERNEL__ | |
13 | #include <linux/if.h> | |
14 | #include <linux/types.h> | |
15 | #include <linux/in.h> | |
16 | #include <linux/if_arp.h> | |
17 | #include <linux/skbuff.h> | |
18 | #endif | |
19 | #include <linux/compiler.h> | |
20 | #include <linux/netfilter_arp.h> | |
21 | ||
2e4e6a17 HW |
22 | #include <linux/netfilter/x_tables.h> |
23 | ||
24 | #define ARPT_FUNCTION_MAXNAMELEN XT_FUNCTION_MAXNAMELEN | |
25 | #define ARPT_TABLE_MAXNAMELEN XT_TABLE_MAXNAMELEN | |
26 | #define arpt_target xt_target | |
27 | #define arpt_table xt_table | |
1da177e4 LT |
28 | |
29 | #define ARPT_DEV_ADDR_LEN_MAX 16 | |
30 | ||
31 | struct arpt_devaddr_info { | |
32 | char addr[ARPT_DEV_ADDR_LEN_MAX]; | |
33 | char mask[ARPT_DEV_ADDR_LEN_MAX]; | |
34 | }; | |
35 | ||
36 | /* Yes, Virginia, you have to zero the padding. */ | |
37 | struct arpt_arp { | |
38 | /* Source and target IP addr */ | |
39 | struct in_addr src, tgt; | |
40 | /* Mask for src and target IP addr */ | |
41 | struct in_addr smsk, tmsk; | |
42 | ||
43 | /* Device hw address length, src+target device addresses */ | |
44 | u_int8_t arhln, arhln_mask; | |
45 | struct arpt_devaddr_info src_devaddr; | |
46 | struct arpt_devaddr_info tgt_devaddr; | |
47 | ||
48 | /* ARP operation code. */ | |
49 | u_int16_t arpop, arpop_mask; | |
50 | ||
51 | /* ARP hardware address and protocol address format. */ | |
52 | u_int16_t arhrd, arhrd_mask; | |
53 | u_int16_t arpro, arpro_mask; | |
54 | ||
55 | /* The protocol address length is only accepted if it is 4 | |
56 | * so there is no use in offering a way to do filtering on it. | |
57 | */ | |
58 | ||
59 | char iniface[IFNAMSIZ], outiface[IFNAMSIZ]; | |
60 | unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ]; | |
61 | ||
62 | /* Flags word */ | |
63 | u_int8_t flags; | |
64 | /* Inverse flags */ | |
65 | u_int16_t invflags; | |
66 | }; | |
67 | ||
1e30a014 DM |
68 | #define arpt_entry_target xt_entry_target |
69 | #define arpt_standard_target xt_standard_target | |
1da177e4 | 70 | |
1da177e4 LT |
71 | /* Values for "flag" field in struct arpt_ip (general arp structure). |
72 | * No flags defined yet. | |
73 | */ | |
74 | #define ARPT_F_MASK 0x00 /* All possible flag bits mask. */ | |
75 | ||
76 | /* Values for "inv" field in struct arpt_arp. */ | |
77 | #define ARPT_INV_VIA_IN 0x0001 /* Invert the sense of IN IFACE. */ | |
78 | #define ARPT_INV_VIA_OUT 0x0002 /* Invert the sense of OUT IFACE */ | |
79 | #define ARPT_INV_SRCIP 0x0004 /* Invert the sense of SRC IP. */ | |
80 | #define ARPT_INV_TGTIP 0x0008 /* Invert the sense of TGT IP. */ | |
81 | #define ARPT_INV_SRCDEVADDR 0x0010 /* Invert the sense of SRC DEV ADDR. */ | |
82 | #define ARPT_INV_TGTDEVADDR 0x0020 /* Invert the sense of TGT DEV ADDR. */ | |
83 | #define ARPT_INV_ARPOP 0x0040 /* Invert the sense of ARP OP. */ | |
84 | #define ARPT_INV_ARPHRD 0x0080 /* Invert the sense of ARP HRD. */ | |
85 | #define ARPT_INV_ARPPRO 0x0100 /* Invert the sense of ARP PRO. */ | |
86 | #define ARPT_INV_ARPHLN 0x0200 /* Invert the sense of ARP HLN. */ | |
87 | #define ARPT_INV_MASK 0x03FF /* All possible flag bits mask. */ | |
88 | ||
89 | /* This structure defines each of the firewall rules. Consists of 3 | |
90 | parts which are 1) general ARP header stuff 2) match specific | |
91 | stuff 3) the target to perform if the rule matches */ | |
92 | struct arpt_entry | |
93 | { | |
94 | struct arpt_arp arp; | |
95 | ||
96 | /* Size of arpt_entry + matches */ | |
97 | u_int16_t target_offset; | |
98 | /* Size of arpt_entry + matches + target */ | |
99 | u_int16_t next_offset; | |
100 | ||
101 | /* Back pointer */ | |
102 | unsigned int comefrom; | |
103 | ||
104 | /* Packet and byte counters. */ | |
2e4e6a17 | 105 | struct xt_counters counters; |
1da177e4 LT |
106 | |
107 | /* The matches (if any), then the target. */ | |
108 | unsigned char elems[0]; | |
109 | }; | |
110 | ||
111 | /* | |
112 | * New IP firewall options for [gs]etsockopt at the RAW IP level. | |
113 | * Unlike BSD Linux inherits IP options so you don't have to use a raw | |
114 | * socket for this. Instead we check rights in the calls. | |
115 | */ | |
2e4e6a17 HW |
116 | #define ARPT_CTL_OFFSET 32 |
117 | #define ARPT_BASE_CTL (XT_BASE_CTL+ARPT_CTL_OFFSET) | |
1da177e4 | 118 | |
2e4e6a17 HW |
119 | #define ARPT_SO_SET_REPLACE (XT_SO_SET_REPLACE+ARPT_CTL_OFFSET) |
120 | #define ARPT_SO_SET_ADD_COUNTERS (XT_SO_SET_ADD_COUNTERS+ARPT_CTL_OFFSET) | |
121 | #define ARPT_SO_SET_MAX (XT_SO_SET_MAX+ARPT_CTL_OFFSET) | |
1da177e4 | 122 | |
2e4e6a17 HW |
123 | #define ARPT_SO_GET_INFO (XT_SO_GET_INFO+ARPT_CTL_OFFSET) |
124 | #define ARPT_SO_GET_ENTRIES (XT_SO_GET_ENTRIES+ARPT_CTL_OFFSET) | |
125 | /* #define ARPT_SO_GET_REVISION_MATCH XT_SO_GET_REVISION_MATCH */ | |
126 | #define ARPT_SO_GET_REVISION_TARGET (XT_SO_GET_REVISION_TARGET+ARPT_CTL_OFFSET) | |
127 | #define ARPT_SO_GET_MAX (XT_SO_GET_REVISION_TARGET+ARPT_CTL_OFFSET) | |
1da177e4 LT |
128 | |
129 | /* CONTINUE verdict for targets */ | |
2e4e6a17 | 130 | #define ARPT_CONTINUE XT_CONTINUE |
1da177e4 LT |
131 | |
132 | /* For standard target */ | |
2e4e6a17 | 133 | #define ARPT_RETURN XT_RETURN |
1da177e4 LT |
134 | |
135 | /* The argument to ARPT_SO_GET_INFO */ | |
136 | struct arpt_getinfo | |
137 | { | |
138 | /* Which table: caller fills this in. */ | |
139 | char name[ARPT_TABLE_MAXNAMELEN]; | |
140 | ||
141 | /* Kernel fills these in. */ | |
142 | /* Which hook entry points are valid: bitmask */ | |
143 | unsigned int valid_hooks; | |
144 | ||
145 | /* Hook entry points: one per netfilter hook. */ | |
146 | unsigned int hook_entry[NF_ARP_NUMHOOKS]; | |
147 | ||
148 | /* Underflow points. */ | |
149 | unsigned int underflow[NF_ARP_NUMHOOKS]; | |
150 | ||
151 | /* Number of entries */ | |
152 | unsigned int num_entries; | |
153 | ||
154 | /* Size of entries. */ | |
155 | unsigned int size; | |
156 | }; | |
157 | ||
158 | /* The argument to ARPT_SO_SET_REPLACE. */ | |
159 | struct arpt_replace | |
160 | { | |
161 | /* Which table. */ | |
162 | char name[ARPT_TABLE_MAXNAMELEN]; | |
163 | ||
164 | /* Which hook entry points are valid: bitmask. You can't | |
165 | change this. */ | |
166 | unsigned int valid_hooks; | |
167 | ||
168 | /* Number of entries */ | |
169 | unsigned int num_entries; | |
170 | ||
171 | /* Total size of new entries */ | |
172 | unsigned int size; | |
173 | ||
174 | /* Hook entry points. */ | |
175 | unsigned int hook_entry[NF_ARP_NUMHOOKS]; | |
176 | ||
177 | /* Underflow points. */ | |
178 | unsigned int underflow[NF_ARP_NUMHOOKS]; | |
179 | ||
180 | /* Information about old entries: */ | |
181 | /* Number of counters (must be equal to current number of entries). */ | |
182 | unsigned int num_counters; | |
183 | /* The old entries' counters. */ | |
2e4e6a17 | 184 | struct xt_counters __user *counters; |
1da177e4 LT |
185 | |
186 | /* The entries (hang off end: not really an array). */ | |
187 | struct arpt_entry entries[0]; | |
188 | }; | |
189 | ||
190 | /* The argument to ARPT_SO_ADD_COUNTERS. */ | |
2e4e6a17 | 191 | #define arpt_counters_info xt_counters_info |
1da177e4 LT |
192 | |
193 | /* The argument to ARPT_SO_GET_ENTRIES. */ | |
194 | struct arpt_get_entries | |
195 | { | |
196 | /* Which table: user fills this in. */ | |
197 | char name[ARPT_TABLE_MAXNAMELEN]; | |
198 | ||
199 | /* User fills this in: total entry size. */ | |
200 | unsigned int size; | |
201 | ||
202 | /* The entries. */ | |
203 | struct arpt_entry entrytable[0]; | |
204 | }; | |
205 | ||
206 | /* Standard return verdict, or do jump. */ | |
2e4e6a17 | 207 | #define ARPT_STANDARD_TARGET XT_STANDARD_TARGET |
1da177e4 | 208 | /* Error verdict. */ |
2e4e6a17 | 209 | #define ARPT_ERROR_TARGET XT_ERROR_TARGET |
1da177e4 LT |
210 | |
211 | /* Helper functions */ | |
212 | static __inline__ struct arpt_entry_target *arpt_get_target(struct arpt_entry *e) | |
213 | { | |
214 | return (void *)e + e->target_offset; | |
215 | } | |
216 | ||
217 | /* fn returns 0 to continue iteration */ | |
218 | #define ARPT_ENTRY_ITERATE(entries, size, fn, args...) \ | |
219 | ({ \ | |
220 | unsigned int __i; \ | |
221 | int __ret = 0; \ | |
222 | struct arpt_entry *__entry; \ | |
223 | \ | |
224 | for (__i = 0; __i < (size); __i += __entry->next_offset) { \ | |
225 | __entry = (void *)(entries) + __i; \ | |
226 | \ | |
227 | __ret = fn(__entry , ## args); \ | |
228 | if (__ret != 0) \ | |
229 | break; \ | |
230 | } \ | |
231 | __ret; \ | |
232 | }) | |
233 | ||
234 | /* | |
235 | * Main firewall chains definitions and global var's definitions. | |
236 | */ | |
237 | #ifdef __KERNEL__ | |
238 | ||
a45049c5 PNA |
239 | #define arpt_register_target(tgt) \ |
240 | ({ (tgt)->family = NF_ARP; \ | |
241 | xt_register_target(tgt); }) | |
242 | #define arpt_unregister_target(tgt) xt_unregister_target(tgt) | |
1da177e4 LT |
243 | |
244 | extern int arpt_register_table(struct arpt_table *table, | |
245 | const struct arpt_replace *repl); | |
246 | extern void arpt_unregister_table(struct arpt_table *table); | |
247 | extern unsigned int arpt_do_table(struct sk_buff **pskb, | |
248 | unsigned int hook, | |
249 | const struct net_device *in, | |
250 | const struct net_device *out, | |
251 | struct arpt_table *table, | |
252 | void *userdata); | |
253 | ||
254 | #define ARPT_ALIGN(s) (((s) + (__alignof__(struct arpt_entry)-1)) & ~(__alignof__(struct arpt_entry)-1)) | |
255 | #endif /*__KERNEL__*/ | |
256 | #endif /* _ARPTABLES_H */ |