Commit | Line | Data |
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1da177e4 LT |
1 | /* Kernel module to match the bridge port in and |
2 | * out device for IP packets coming into contact with a bridge. */ | |
3 | ||
4 | /* (C) 2001-2003 Bart De Schuymer <bdschuym@pandora.be> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | */ | |
10 | ||
11 | #include <linux/module.h> | |
12 | #include <linux/skbuff.h> | |
deb47c66 | 13 | #include <linux/netfilter_bridge.h> |
2e4e6a17 HW |
14 | #include <linux/netfilter/xt_physdev.h> |
15 | #include <linux/netfilter/x_tables.h> | |
1da177e4 | 16 | #include <linux/netfilter_bridge.h> |
1da177e4 LT |
17 | |
18 | MODULE_LICENSE("GPL"); | |
19 | MODULE_AUTHOR("Bart De Schuymer <bdschuym@pandora.be>"); | |
20 | MODULE_DESCRIPTION("iptables bridge physical device match module"); | |
2e4e6a17 HW |
21 | MODULE_ALIAS("ipt_physdev"); |
22 | MODULE_ALIAS("ip6t_physdev"); | |
1da177e4 | 23 | |
1d93a9cb | 24 | static bool |
1da177e4 LT |
25 | match(const struct sk_buff *skb, |
26 | const struct net_device *in, | |
27 | const struct net_device *out, | |
c4986734 | 28 | const struct xt_match *match, |
1da177e4 LT |
29 | const void *matchinfo, |
30 | int offset, | |
31 | unsigned int protoff, | |
cff533ac | 32 | bool *hotdrop) |
1da177e4 LT |
33 | { |
34 | int i; | |
35 | static const char nulldevname[IFNAMSIZ]; | |
2e4e6a17 | 36 | const struct xt_physdev_info *info = matchinfo; |
1d93a9cb | 37 | bool ret; |
1da177e4 LT |
38 | const char *indev, *outdev; |
39 | struct nf_bridge_info *nf_bridge; | |
40 | ||
41 | /* Not a bridged IP packet or no info available yet: | |
42 | * LOCAL_OUT/mangle and LOCAL_OUT/nat don't know if | |
43 | * the destination device will be a bridge. */ | |
44 | if (!(nf_bridge = skb->nf_bridge)) { | |
45 | /* Return MATCH if the invert flags of the used options are on */ | |
2e4e6a17 HW |
46 | if ((info->bitmask & XT_PHYSDEV_OP_BRIDGED) && |
47 | !(info->invert & XT_PHYSDEV_OP_BRIDGED)) | |
1d93a9cb | 48 | return false; |
2e4e6a17 HW |
49 | if ((info->bitmask & XT_PHYSDEV_OP_ISIN) && |
50 | !(info->invert & XT_PHYSDEV_OP_ISIN)) | |
1d93a9cb | 51 | return false; |
2e4e6a17 HW |
52 | if ((info->bitmask & XT_PHYSDEV_OP_ISOUT) && |
53 | !(info->invert & XT_PHYSDEV_OP_ISOUT)) | |
1d93a9cb | 54 | return false; |
2e4e6a17 HW |
55 | if ((info->bitmask & XT_PHYSDEV_OP_IN) && |
56 | !(info->invert & XT_PHYSDEV_OP_IN)) | |
1d93a9cb | 57 | return false; |
2e4e6a17 HW |
58 | if ((info->bitmask & XT_PHYSDEV_OP_OUT) && |
59 | !(info->invert & XT_PHYSDEV_OP_OUT)) | |
1d93a9cb JE |
60 | return false; |
61 | return true; | |
1da177e4 LT |
62 | } |
63 | ||
64 | /* This only makes sense in the FORWARD and POSTROUTING chains */ | |
2e4e6a17 | 65 | if ((info->bitmask & XT_PHYSDEV_OP_BRIDGED) && |
1da177e4 | 66 | (!!(nf_bridge->mask & BRNF_BRIDGED) ^ |
2e4e6a17 | 67 | !(info->invert & XT_PHYSDEV_OP_BRIDGED))) |
1d93a9cb | 68 | return false; |
1da177e4 | 69 | |
2e4e6a17 HW |
70 | if ((info->bitmask & XT_PHYSDEV_OP_ISIN && |
71 | (!nf_bridge->physindev ^ !!(info->invert & XT_PHYSDEV_OP_ISIN))) || | |
72 | (info->bitmask & XT_PHYSDEV_OP_ISOUT && | |
73 | (!nf_bridge->physoutdev ^ !!(info->invert & XT_PHYSDEV_OP_ISOUT)))) | |
1d93a9cb | 74 | return false; |
1da177e4 | 75 | |
2e4e6a17 | 76 | if (!(info->bitmask & XT_PHYSDEV_OP_IN)) |
1da177e4 LT |
77 | goto match_outdev; |
78 | indev = nf_bridge->physindev ? nf_bridge->physindev->name : nulldevname; | |
1d93a9cb | 79 | for (i = 0, ret = false; i < IFNAMSIZ/sizeof(unsigned int); i++) { |
1da177e4 LT |
80 | ret |= (((const unsigned int *)indev)[i] |
81 | ^ ((const unsigned int *)info->physindev)[i]) | |
82 | & ((const unsigned int *)info->in_mask)[i]; | |
83 | } | |
84 | ||
1d93a9cb JE |
85 | if (!ret ^ !(info->invert & XT_PHYSDEV_OP_IN)) |
86 | return false; | |
1da177e4 LT |
87 | |
88 | match_outdev: | |
2e4e6a17 | 89 | if (!(info->bitmask & XT_PHYSDEV_OP_OUT)) |
1d93a9cb | 90 | return true; |
1da177e4 LT |
91 | outdev = nf_bridge->physoutdev ? |
92 | nf_bridge->physoutdev->name : nulldevname; | |
1d93a9cb | 93 | for (i = 0, ret = false; i < IFNAMSIZ/sizeof(unsigned int); i++) { |
1da177e4 LT |
94 | ret |= (((const unsigned int *)outdev)[i] |
95 | ^ ((const unsigned int *)info->physoutdev)[i]) | |
96 | & ((const unsigned int *)info->out_mask)[i]; | |
97 | } | |
98 | ||
1d93a9cb | 99 | return ret ^ !(info->invert & XT_PHYSDEV_OP_OUT); |
1da177e4 LT |
100 | } |
101 | ||
ccb79bdc | 102 | static bool |
1da177e4 | 103 | checkentry(const char *tablename, |
2e4e6a17 | 104 | const void *ip, |
c4986734 | 105 | const struct xt_match *match, |
1da177e4 | 106 | void *matchinfo, |
1da177e4 LT |
107 | unsigned int hook_mask) |
108 | { | |
2e4e6a17 | 109 | const struct xt_physdev_info *info = matchinfo; |
1da177e4 | 110 | |
2e4e6a17 HW |
111 | if (!(info->bitmask & XT_PHYSDEV_OP_MASK) || |
112 | info->bitmask & ~XT_PHYSDEV_OP_MASK) | |
ccb79bdc | 113 | return false; |
2bf540b7 | 114 | if (info->bitmask & XT_PHYSDEV_OP_OUT && |
10ea6ac8 PM |
115 | (!(info->bitmask & XT_PHYSDEV_OP_BRIDGED) || |
116 | info->invert & XT_PHYSDEV_OP_BRIDGED) && | |
117 | hook_mask & ((1 << NF_IP_LOCAL_OUT) | (1 << NF_IP_FORWARD) | | |
601e68e1 | 118 | (1 << NF_IP_POST_ROUTING))) { |
10ea6ac8 PM |
119 | printk(KERN_WARNING "physdev match: using --physdev-out in the " |
120 | "OUTPUT, FORWARD and POSTROUTING chains for non-bridged " | |
2bf540b7 PM |
121 | "traffic is not supported anymore.\n"); |
122 | if (hook_mask & (1 << NF_IP_LOCAL_OUT)) | |
ccb79bdc | 123 | return false; |
10ea6ac8 | 124 | } |
ccb79bdc | 125 | return true; |
1da177e4 LT |
126 | } |
127 | ||
4470bbc7 PM |
128 | static struct xt_match xt_physdev_match[] = { |
129 | { | |
130 | .name = "physdev", | |
131 | .family = AF_INET, | |
132 | .checkentry = checkentry, | |
133 | .match = match, | |
134 | .matchsize = sizeof(struct xt_physdev_info), | |
135 | .me = THIS_MODULE, | |
136 | }, | |
137 | { | |
138 | .name = "physdev", | |
139 | .family = AF_INET6, | |
140 | .checkentry = checkentry, | |
141 | .match = match, | |
142 | .matchsize = sizeof(struct xt_physdev_info), | |
143 | .me = THIS_MODULE, | |
144 | }, | |
1da177e4 LT |
145 | }; |
146 | ||
65b4b4e8 | 147 | static int __init xt_physdev_init(void) |
1da177e4 | 148 | { |
4470bbc7 PM |
149 | return xt_register_matches(xt_physdev_match, |
150 | ARRAY_SIZE(xt_physdev_match)); | |
1da177e4 LT |
151 | } |
152 | ||
65b4b4e8 | 153 | static void __exit xt_physdev_fini(void) |
1da177e4 | 154 | { |
4470bbc7 | 155 | xt_unregister_matches(xt_physdev_match, ARRAY_SIZE(xt_physdev_match)); |
1da177e4 LT |
156 | } |
157 | ||
65b4b4e8 AM |
158 | module_init(xt_physdev_init); |
159 | module_exit(xt_physdev_fini); |