Commit | Line | Data |
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1da177e4 LT |
1 | /* This kernel module is used to modify the connection mark values, or |
2 | * to optionally restore the skb nfmark from the connection mark | |
3 | * | |
4 | * Copyright (C) 2002,2004 MARA Systems AB <http://www.marasystems.com> | |
5 | * by Henrik Nordstrom <hno@marasystems.com> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License as published by | |
9 | * the Free Software Foundation; either version 2 of the License, or | |
10 | * (at your option) any later version. | |
11 | * | |
12 | * This program is distributed in the hope that it will be useful, | |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | * GNU General Public License for more details. | |
16 | * | |
17 | * You should have received a copy of the GNU General Public License | |
18 | * along with this program; if not, write to the Free Software | |
19 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
20 | */ | |
21 | #include <linux/module.h> | |
22 | #include <linux/skbuff.h> | |
23 | #include <linux/ip.h> | |
24 | #include <net/checksum.h> | |
25 | ||
26 | MODULE_AUTHOR("Henrik Nordstrom <hno@marasytems.com>"); | |
27 | MODULE_DESCRIPTION("IP tables CONNMARK matching module"); | |
28 | MODULE_LICENSE("GPL"); | |
2e4e6a17 | 29 | MODULE_ALIAS("ipt_CONNMARK"); |
1da177e4 | 30 | |
2e4e6a17 HW |
31 | #include <linux/netfilter/x_tables.h> |
32 | #include <linux/netfilter/xt_CONNMARK.h> | |
9fb9cbb1 | 33 | #include <net/netfilter/nf_conntrack_compat.h> |
1da177e4 LT |
34 | |
35 | static unsigned int | |
36 | target(struct sk_buff **pskb, | |
37 | const struct net_device *in, | |
38 | const struct net_device *out, | |
39 | unsigned int hooknum, | |
c4986734 | 40 | const struct xt_target *target, |
fe1cb108 | 41 | const void *targinfo) |
1da177e4 | 42 | { |
2e4e6a17 | 43 | const struct xt_connmark_target_info *markinfo = targinfo; |
bf3a46aa HW |
44 | u_int32_t diff; |
45 | u_int32_t nfmark; | |
46 | u_int32_t newmark; | |
9fb9cbb1 YK |
47 | u_int32_t ctinfo; |
48 | u_int32_t *ctmark = nf_ct_get_mark(*pskb, &ctinfo); | |
1da177e4 | 49 | |
9fb9cbb1 | 50 | if (ctmark) { |
90528e6f PM |
51 | switch(markinfo->mode) { |
52 | case XT_CONNMARK_SET: | |
53 | newmark = (*ctmark & ~markinfo->mask) | markinfo->mark; | |
54 | if (newmark != *ctmark) { | |
55 | *ctmark = newmark; | |
0719bdf1 | 56 | #if defined(CONFIG_IP_NF_CONNTRACK) || defined(CONFIG_IP_NF_CONNTRACK_MODULE) |
90528e6f | 57 | ip_conntrack_event_cache(IPCT_MARK, *pskb); |
2521c12c | 58 | #else |
90528e6f | 59 | nf_conntrack_event_cache(IPCT_MARK, *pskb); |
2521c12c PNA |
60 | #endif |
61 | } | |
90528e6f PM |
62 | break; |
63 | case XT_CONNMARK_SAVE: | |
64 | newmark = (*ctmark & ~markinfo->mask) | | |
65 | ((*pskb)->nfmark & markinfo->mask); | |
66 | if (*ctmark != newmark) { | |
67 | *ctmark = newmark; | |
0719bdf1 | 68 | #if defined(CONFIG_IP_NF_CONNTRACK) || defined(CONFIG_IP_NF_CONNTRACK_MODULE) |
90528e6f | 69 | ip_conntrack_event_cache(IPCT_MARK, *pskb); |
2521c12c | 70 | #else |
90528e6f | 71 | nf_conntrack_event_cache(IPCT_MARK, *pskb); |
2521c12c | 72 | #endif |
90528e6f PM |
73 | } |
74 | break; | |
75 | case XT_CONNMARK_RESTORE: | |
76 | nfmark = (*pskb)->nfmark; | |
77 | diff = (*ctmark ^ nfmark) & markinfo->mask; | |
78 | if (diff != 0) | |
79 | (*pskb)->nfmark = nfmark ^ diff; | |
80 | break; | |
2521c12c | 81 | } |
1da177e4 LT |
82 | } |
83 | ||
2e4e6a17 | 84 | return XT_CONTINUE; |
1da177e4 LT |
85 | } |
86 | ||
87 | static int | |
88 | checkentry(const char *tablename, | |
2e4e6a17 | 89 | const void *entry, |
c4986734 | 90 | const struct xt_target *target, |
1da177e4 | 91 | void *targinfo, |
1da177e4 LT |
92 | unsigned int hook_mask) |
93 | { | |
2e4e6a17 | 94 | struct xt_connmark_target_info *matchinfo = targinfo; |
1da177e4 | 95 | |
2e4e6a17 | 96 | if (matchinfo->mode == XT_CONNMARK_RESTORE) { |
90528e6f PM |
97 | if (strcmp(tablename, "mangle") != 0) { |
98 | printk(KERN_WARNING "CONNMARK: restore can only be " | |
99 | "called from \"mangle\" table, not \"%s\"\n", | |
100 | tablename); | |
101 | return 0; | |
102 | } | |
1da177e4 | 103 | } |
bf3a46aa HW |
104 | if (matchinfo->mark > 0xffffffff || matchinfo->mask > 0xffffffff) { |
105 | printk(KERN_WARNING "CONNMARK: Only supports 32bit mark\n"); | |
106 | return 0; | |
107 | } | |
1da177e4 LT |
108 | return 1; |
109 | } | |
110 | ||
4470bbc7 PM |
111 | static struct xt_target xt_connmark_target[] = { |
112 | { | |
113 | .name = "CONNMARK", | |
114 | .family = AF_INET, | |
115 | .checkentry = checkentry, | |
116 | .target = target, | |
117 | .targetsize = sizeof(struct xt_connmark_target_info), | |
118 | .me = THIS_MODULE | |
119 | }, | |
120 | { | |
121 | .name = "CONNMARK", | |
122 | .family = AF_INET6, | |
123 | .checkentry = checkentry, | |
124 | .target = target, | |
125 | .targetsize = sizeof(struct xt_connmark_target_info), | |
126 | .me = THIS_MODULE | |
127 | }, | |
1da177e4 LT |
128 | }; |
129 | ||
65b4b4e8 | 130 | static int __init xt_connmark_init(void) |
1da177e4 | 131 | { |
2e4e6a17 | 132 | need_conntrack(); |
4470bbc7 PM |
133 | return xt_register_targets(xt_connmark_target, |
134 | ARRAY_SIZE(xt_connmark_target)); | |
1da177e4 LT |
135 | } |
136 | ||
65b4b4e8 | 137 | static void __exit xt_connmark_fini(void) |
1da177e4 | 138 | { |
4470bbc7 PM |
139 | xt_unregister_targets(xt_connmark_target, |
140 | ARRAY_SIZE(xt_connmark_target)); | |
1da177e4 LT |
141 | } |
142 | ||
65b4b4e8 AM |
143 | module_init(xt_connmark_init); |
144 | module_exit(xt_connmark_fini); |