Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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"); |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 29 | MODULE_ALIAS("ipt_CONNMARK"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 31 | #include <linux/netfilter/x_tables.h> |
| 32 | #include <linux/netfilter/xt_CONNMARK.h> |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 33 | #include <net/netfilter/nf_conntrack_compat.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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, |
Patrick McHardy | c498673 | 2006-03-20 18:02:56 -0800 | [diff] [blame] | 40 | const struct xt_target *target, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | const void *targinfo, |
| 42 | void *userinfo) |
| 43 | { |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 44 | const struct xt_connmark_target_info *markinfo = targinfo; |
Harald Welte | bf3a46a | 2005-08-09 19:22:01 -0700 | [diff] [blame] | 45 | u_int32_t diff; |
| 46 | u_int32_t nfmark; |
| 47 | u_int32_t newmark; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 48 | u_int32_t ctinfo; |
| 49 | u_int32_t *ctmark = nf_ct_get_mark(*pskb, &ctinfo); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 51 | if (ctmark) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | switch(markinfo->mode) { |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 53 | case XT_CONNMARK_SET: |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 54 | newmark = (*ctmark & ~markinfo->mask) | markinfo->mark; |
| 55 | if (newmark != *ctmark) |
| 56 | *ctmark = newmark; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | break; |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 58 | case XT_CONNMARK_SAVE: |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 59 | newmark = (*ctmark & ~markinfo->mask) | ((*pskb)->nfmark & markinfo->mask); |
| 60 | if (*ctmark != newmark) |
| 61 | *ctmark = newmark; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | break; |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 63 | case XT_CONNMARK_RESTORE: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | nfmark = (*pskb)->nfmark; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 65 | diff = (*ctmark ^ nfmark) & markinfo->mask; |
Harald Welte | 6869c4d | 2005-08-09 19:24:19 -0700 | [diff] [blame] | 66 | if (diff != 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 67 | (*pskb)->nfmark = nfmark ^ diff; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | break; |
| 69 | } |
| 70 | } |
| 71 | |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 72 | return XT_CONTINUE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | } |
| 74 | |
| 75 | static int |
| 76 | checkentry(const char *tablename, |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 77 | const void *entry, |
Patrick McHardy | c498673 | 2006-03-20 18:02:56 -0800 | [diff] [blame] | 78 | const struct xt_target *target, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 79 | void *targinfo, |
| 80 | unsigned int targinfosize, |
| 81 | unsigned int hook_mask) |
| 82 | { |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 83 | struct xt_connmark_target_info *matchinfo = targinfo; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 85 | if (matchinfo->mode == XT_CONNMARK_RESTORE) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 86 | if (strcmp(tablename, "mangle") != 0) { |
| 87 | printk(KERN_WARNING "CONNMARK: restore can only be called from \"mangle\" table, not \"%s\"\n", tablename); |
| 88 | return 0; |
| 89 | } |
| 90 | } |
| 91 | |
Harald Welte | bf3a46a | 2005-08-09 19:22:01 -0700 | [diff] [blame] | 92 | if (matchinfo->mark > 0xffffffff || matchinfo->mask > 0xffffffff) { |
| 93 | printk(KERN_WARNING "CONNMARK: Only supports 32bit mark\n"); |
| 94 | return 0; |
| 95 | } |
| 96 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | return 1; |
| 98 | } |
| 99 | |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 100 | static struct xt_target connmark_reg = { |
Patrick McHardy | 5d04bff | 2006-03-20 18:01:58 -0800 | [diff] [blame] | 101 | .name = "CONNMARK", |
| 102 | .target = target, |
| 103 | .targetsize = sizeof(struct xt_connmark_target_info), |
| 104 | .checkentry = checkentry, |
Pablo Neira Ayuso | a45049c | 2006-03-22 13:55:40 -0800 | [diff] [blame] | 105 | .family = AF_INET, |
Patrick McHardy | 5d04bff | 2006-03-20 18:01:58 -0800 | [diff] [blame] | 106 | .me = THIS_MODULE |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 107 | }; |
Patrick McHardy | 5d04bff | 2006-03-20 18:01:58 -0800 | [diff] [blame] | 108 | |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 109 | static struct xt_target connmark6_reg = { |
Patrick McHardy | 5d04bff | 2006-03-20 18:01:58 -0800 | [diff] [blame] | 110 | .name = "CONNMARK", |
| 111 | .target = target, |
| 112 | .targetsize = sizeof(struct xt_connmark_target_info), |
| 113 | .checkentry = checkentry, |
Pablo Neira Ayuso | a45049c | 2006-03-22 13:55:40 -0800 | [diff] [blame] | 114 | .family = AF_INET6, |
Patrick McHardy | 5d04bff | 2006-03-20 18:01:58 -0800 | [diff] [blame] | 115 | .me = THIS_MODULE |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | }; |
| 117 | |
Andrew Morton | 65b4b4e | 2006-03-28 16:37:06 -0800 | [diff] [blame] | 118 | static int __init xt_connmark_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | { |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 120 | int ret; |
| 121 | |
| 122 | need_conntrack(); |
| 123 | |
Pablo Neira Ayuso | a45049c | 2006-03-22 13:55:40 -0800 | [diff] [blame] | 124 | ret = xt_register_target(&connmark_reg); |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 125 | if (ret) |
| 126 | return ret; |
| 127 | |
Pablo Neira Ayuso | a45049c | 2006-03-22 13:55:40 -0800 | [diff] [blame] | 128 | ret = xt_register_target(&connmark6_reg); |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 129 | if (ret) |
Pablo Neira Ayuso | a45049c | 2006-03-22 13:55:40 -0800 | [diff] [blame] | 130 | xt_unregister_target(&connmark_reg); |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 131 | |
| 132 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 133 | } |
| 134 | |
Andrew Morton | 65b4b4e | 2006-03-28 16:37:06 -0800 | [diff] [blame] | 135 | static void __exit xt_connmark_fini(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | { |
Pablo Neira Ayuso | a45049c | 2006-03-22 13:55:40 -0800 | [diff] [blame] | 137 | xt_unregister_target(&connmark_reg); |
| 138 | xt_unregister_target(&connmark6_reg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | } |
| 140 | |
Andrew Morton | 65b4b4e | 2006-03-28 16:37:06 -0800 | [diff] [blame] | 141 | module_init(xt_connmark_init); |
| 142 | module_exit(xt_connmark_fini); |