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 LT |
16 | #include <linux/netfilter_bridge.h> |
17 | #define MATCH 1 | |
18 | #define NOMATCH 0 | |
19 | ||
20 | MODULE_LICENSE("GPL"); | |
21 | MODULE_AUTHOR("Bart De Schuymer <bdschuym@pandora.be>"); | |
22 | MODULE_DESCRIPTION("iptables bridge physical device match module"); | |
2e4e6a17 HW |
23 | MODULE_ALIAS("ipt_physdev"); |
24 | MODULE_ALIAS("ip6t_physdev"); | |
1da177e4 LT |
25 | |
26 | static int | |
27 | match(const struct sk_buff *skb, | |
28 | const struct net_device *in, | |
29 | const struct net_device *out, | |
c4986734 | 30 | const struct xt_match *match, |
1da177e4 LT |
31 | const void *matchinfo, |
32 | int offset, | |
33 | unsigned int protoff, | |
34 | int *hotdrop) | |
35 | { | |
36 | int i; | |
37 | static const char nulldevname[IFNAMSIZ]; | |
2e4e6a17 | 38 | const struct xt_physdev_info *info = matchinfo; |
1da177e4 LT |
39 | unsigned int ret; |
40 | const char *indev, *outdev; | |
41 | struct nf_bridge_info *nf_bridge; | |
42 | ||
43 | /* Not a bridged IP packet or no info available yet: | |
44 | * LOCAL_OUT/mangle and LOCAL_OUT/nat don't know if | |
45 | * the destination device will be a bridge. */ | |
46 | if (!(nf_bridge = skb->nf_bridge)) { | |
47 | /* Return MATCH if the invert flags of the used options are on */ | |
2e4e6a17 HW |
48 | if ((info->bitmask & XT_PHYSDEV_OP_BRIDGED) && |
49 | !(info->invert & XT_PHYSDEV_OP_BRIDGED)) | |
1da177e4 | 50 | return NOMATCH; |
2e4e6a17 HW |
51 | if ((info->bitmask & XT_PHYSDEV_OP_ISIN) && |
52 | !(info->invert & XT_PHYSDEV_OP_ISIN)) | |
1da177e4 | 53 | return NOMATCH; |
2e4e6a17 HW |
54 | if ((info->bitmask & XT_PHYSDEV_OP_ISOUT) && |
55 | !(info->invert & XT_PHYSDEV_OP_ISOUT)) | |
1da177e4 | 56 | return NOMATCH; |
2e4e6a17 HW |
57 | if ((info->bitmask & XT_PHYSDEV_OP_IN) && |
58 | !(info->invert & XT_PHYSDEV_OP_IN)) | |
1da177e4 | 59 | return NOMATCH; |
2e4e6a17 HW |
60 | if ((info->bitmask & XT_PHYSDEV_OP_OUT) && |
61 | !(info->invert & XT_PHYSDEV_OP_OUT)) | |
1da177e4 LT |
62 | return NOMATCH; |
63 | return MATCH; | |
64 | } | |
65 | ||
66 | /* This only makes sense in the FORWARD and POSTROUTING chains */ | |
2e4e6a17 | 67 | if ((info->bitmask & XT_PHYSDEV_OP_BRIDGED) && |
1da177e4 | 68 | (!!(nf_bridge->mask & BRNF_BRIDGED) ^ |
2e4e6a17 | 69 | !(info->invert & XT_PHYSDEV_OP_BRIDGED))) |
1da177e4 LT |
70 | return NOMATCH; |
71 | ||
2e4e6a17 HW |
72 | if ((info->bitmask & XT_PHYSDEV_OP_ISIN && |
73 | (!nf_bridge->physindev ^ !!(info->invert & XT_PHYSDEV_OP_ISIN))) || | |
74 | (info->bitmask & XT_PHYSDEV_OP_ISOUT && | |
75 | (!nf_bridge->physoutdev ^ !!(info->invert & XT_PHYSDEV_OP_ISOUT)))) | |
1da177e4 LT |
76 | return NOMATCH; |
77 | ||
2e4e6a17 | 78 | if (!(info->bitmask & XT_PHYSDEV_OP_IN)) |
1da177e4 LT |
79 | goto match_outdev; |
80 | indev = nf_bridge->physindev ? nf_bridge->physindev->name : nulldevname; | |
81 | for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned int); i++) { | |
82 | ret |= (((const unsigned int *)indev)[i] | |
83 | ^ ((const unsigned int *)info->physindev)[i]) | |
84 | & ((const unsigned int *)info->in_mask)[i]; | |
85 | } | |
86 | ||
2e4e6a17 | 87 | if ((ret == 0) ^ !(info->invert & XT_PHYSDEV_OP_IN)) |
1da177e4 LT |
88 | return NOMATCH; |
89 | ||
90 | match_outdev: | |
2e4e6a17 | 91 | if (!(info->bitmask & XT_PHYSDEV_OP_OUT)) |
1da177e4 LT |
92 | return MATCH; |
93 | outdev = nf_bridge->physoutdev ? | |
94 | nf_bridge->physoutdev->name : nulldevname; | |
95 | for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned int); i++) { | |
96 | ret |= (((const unsigned int *)outdev)[i] | |
97 | ^ ((const unsigned int *)info->physoutdev)[i]) | |
98 | & ((const unsigned int *)info->out_mask)[i]; | |
99 | } | |
100 | ||
2e4e6a17 | 101 | return (ret != 0) ^ !(info->invert & XT_PHYSDEV_OP_OUT); |
1da177e4 LT |
102 | } |
103 | ||
104 | static int | |
105 | checkentry(const char *tablename, | |
2e4e6a17 | 106 | const void *ip, |
c4986734 | 107 | const struct xt_match *match, |
1da177e4 | 108 | void *matchinfo, |
1da177e4 LT |
109 | unsigned int hook_mask) |
110 | { | |
2e4e6a17 | 111 | const struct xt_physdev_info *info = matchinfo; |
1da177e4 | 112 | |
2e4e6a17 HW |
113 | if (!(info->bitmask & XT_PHYSDEV_OP_MASK) || |
114 | info->bitmask & ~XT_PHYSDEV_OP_MASK) | |
1da177e4 | 115 | return 0; |
10ea6ac8 PM |
116 | if (brnf_deferred_hooks == 0 && |
117 | info->bitmask & XT_PHYSDEV_OP_OUT && | |
118 | (!(info->bitmask & XT_PHYSDEV_OP_BRIDGED) || | |
119 | info->invert & XT_PHYSDEV_OP_BRIDGED) && | |
120 | hook_mask & ((1 << NF_IP_LOCAL_OUT) | (1 << NF_IP_FORWARD) | | |
121 | (1 << NF_IP_POST_ROUTING))) { | |
122 | printk(KERN_WARNING "physdev match: using --physdev-out in the " | |
123 | "OUTPUT, FORWARD and POSTROUTING chains for non-bridged " | |
124 | "traffic is deprecated and breaks other things, it will " | |
125 | "be removed in January 2007. See Documentation/" | |
126 | "feature-removal-schedule.txt for details. This doesn't " | |
127 | "affect you in case you're using it for purely bridged " | |
128 | "traffic.\n"); | |
129 | brnf_deferred_hooks = 1; | |
130 | } | |
1da177e4 LT |
131 | return 1; |
132 | } | |
133 | ||
4470bbc7 PM |
134 | static struct xt_match xt_physdev_match[] = { |
135 | { | |
136 | .name = "physdev", | |
137 | .family = AF_INET, | |
138 | .checkentry = checkentry, | |
139 | .match = match, | |
140 | .matchsize = sizeof(struct xt_physdev_info), | |
141 | .me = THIS_MODULE, | |
142 | }, | |
143 | { | |
144 | .name = "physdev", | |
145 | .family = AF_INET6, | |
146 | .checkentry = checkentry, | |
147 | .match = match, | |
148 | .matchsize = sizeof(struct xt_physdev_info), | |
149 | .me = THIS_MODULE, | |
150 | }, | |
1da177e4 LT |
151 | }; |
152 | ||
65b4b4e8 | 153 | static int __init xt_physdev_init(void) |
1da177e4 | 154 | { |
4470bbc7 PM |
155 | return xt_register_matches(xt_physdev_match, |
156 | ARRAY_SIZE(xt_physdev_match)); | |
1da177e4 LT |
157 | } |
158 | ||
65b4b4e8 | 159 | static void __exit xt_physdev_fini(void) |
1da177e4 | 160 | { |
4470bbc7 | 161 | xt_unregister_matches(xt_physdev_match, ARRAY_SIZE(xt_physdev_match)); |
1da177e4 LT |
162 | } |
163 | ||
65b4b4e8 AM |
164 | module_init(xt_physdev_init); |
165 | module_exit(xt_physdev_fini); |