James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 1 | /* |
| 2 | * This module is used to copy security markings from packets |
| 3 | * to connections, and restore security markings from connections |
| 4 | * back to packets. This would normally be performed in conjunction |
| 5 | * with the SECMARK target and state match. |
| 6 | * |
| 7 | * Based somewhat on CONNMARK: |
| 8 | * Copyright (C) 2002,2004 MARA Systems AB <http://www.marasystems.com> |
| 9 | * by Henrik Nordstrom <hno@marasystems.com> |
| 10 | * |
| 11 | * (C) 2006 Red Hat, Inc., James Morris <jmorris@redhat.com> |
| 12 | * |
| 13 | * This program is free software; you can redistribute it and/or modify |
| 14 | * it under the terms of the GNU General Public License version 2 as |
| 15 | * published by the Free Software Foundation. |
| 16 | * |
| 17 | */ |
| 18 | #include <linux/module.h> |
| 19 | #include <linux/skbuff.h> |
| 20 | #include <linux/netfilter/x_tables.h> |
| 21 | #include <linux/netfilter/xt_CONNSECMARK.h> |
Patrick McHardy | 587aa64 | 2007-03-14 16:37:25 -0700 | [diff] [blame] | 22 | #include <net/netfilter/nf_conntrack.h> |
Pablo Neira Ayuso | 37fccd8 | 2007-12-17 22:28:41 -0800 | [diff] [blame] | 23 | #include <net/netfilter/nf_conntrack_ecache.h> |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 24 | |
| 25 | #define PFX "CONNSECMARK: " |
| 26 | |
| 27 | MODULE_LICENSE("GPL"); |
| 28 | MODULE_AUTHOR("James Morris <jmorris@redhat.com>"); |
Jan Engelhardt | 2ae15b6 | 2008-01-14 23:42:28 -0800 | [diff] [blame] | 29 | MODULE_DESCRIPTION("Xtables: target for copying between connection and security mark"); |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 30 | MODULE_ALIAS("ipt_CONNSECMARK"); |
| 31 | MODULE_ALIAS("ip6t_CONNSECMARK"); |
| 32 | |
| 33 | /* |
| 34 | * If the packet has a security mark and the connection does not, copy |
| 35 | * the security mark from the packet to the connection. |
| 36 | */ |
Jan Engelhardt | a47362a | 2007-07-07 22:16:55 -0700 | [diff] [blame] | 37 | static void secmark_save(const struct sk_buff *skb) |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 38 | { |
| 39 | if (skb->secmark) { |
Patrick McHardy | 587aa64 | 2007-03-14 16:37:25 -0700 | [diff] [blame] | 40 | struct nf_conn *ct; |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 41 | enum ip_conntrack_info ctinfo; |
| 42 | |
Patrick McHardy | 587aa64 | 2007-03-14 16:37:25 -0700 | [diff] [blame] | 43 | ct = nf_ct_get(skb, &ctinfo); |
Pablo Neira Ayuso | 37fccd8 | 2007-12-17 22:28:41 -0800 | [diff] [blame] | 44 | if (ct && !ct->secmark) { |
Patrick McHardy | 587aa64 | 2007-03-14 16:37:25 -0700 | [diff] [blame] | 45 | ct->secmark = skb->secmark; |
Pablo Neira Ayuso | 37fccd8 | 2007-12-17 22:28:41 -0800 | [diff] [blame] | 46 | nf_conntrack_event_cache(IPCT_SECMARK, skb); |
| 47 | } |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 48 | } |
| 49 | } |
| 50 | |
| 51 | /* |
| 52 | * If packet has no security mark, and the connection does, restore the |
| 53 | * security mark from the connection to the packet. |
| 54 | */ |
| 55 | static void secmark_restore(struct sk_buff *skb) |
| 56 | { |
| 57 | if (!skb->secmark) { |
Patrick McHardy | 587aa64 | 2007-03-14 16:37:25 -0700 | [diff] [blame] | 58 | struct nf_conn *ct; |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 59 | enum ip_conntrack_info ctinfo; |
| 60 | |
Patrick McHardy | 587aa64 | 2007-03-14 16:37:25 -0700 | [diff] [blame] | 61 | ct = nf_ct_get(skb, &ctinfo); |
| 62 | if (ct && ct->secmark) |
| 63 | skb->secmark = ct->secmark; |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 64 | } |
| 65 | } |
| 66 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 67 | static unsigned int |
| 68 | connsecmark_tg(struct sk_buff *skb, const struct net_device *in, |
| 69 | const struct net_device *out, unsigned int hooknum, |
| 70 | const struct xt_target *target, const void *targinfo) |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 71 | { |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 72 | const struct xt_connsecmark_target_info *info = targinfo; |
| 73 | |
| 74 | switch (info->mode) { |
| 75 | case CONNSECMARK_SAVE: |
| 76 | secmark_save(skb); |
| 77 | break; |
| 78 | |
| 79 | case CONNSECMARK_RESTORE: |
| 80 | secmark_restore(skb); |
| 81 | break; |
| 82 | |
| 83 | default: |
| 84 | BUG(); |
| 85 | } |
| 86 | |
| 87 | return XT_CONTINUE; |
| 88 | } |
| 89 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 90 | static bool |
| 91 | connsecmark_tg_check(const char *tablename, const void *entry, |
| 92 | const struct xt_target *target, void *targinfo, |
| 93 | unsigned int hook_mask) |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 94 | { |
Jan Engelhardt | a47362a | 2007-07-07 22:16:55 -0700 | [diff] [blame] | 95 | const struct xt_connsecmark_target_info *info = targinfo; |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 96 | |
| 97 | switch (info->mode) { |
| 98 | case CONNSECMARK_SAVE: |
| 99 | case CONNSECMARK_RESTORE: |
| 100 | break; |
| 101 | |
| 102 | default: |
| 103 | printk(KERN_INFO PFX "invalid mode: %hu\n", info->mode); |
Jan Engelhardt | e1931b7 | 2007-07-07 22:16:26 -0700 | [diff] [blame] | 104 | return false; |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 105 | } |
| 106 | |
Jan Engelhardt | 67b4af2 | 2007-12-01 00:01:50 +1100 | [diff] [blame] | 107 | if (nf_ct_l3proto_try_module_get(target->family) < 0) { |
| 108 | printk(KERN_WARNING "can't load conntrack support for " |
Jan Engelhardt | df54aae | 2007-12-17 22:43:15 -0800 | [diff] [blame] | 109 | "proto=%u\n", target->family); |
Jan Engelhardt | 67b4af2 | 2007-12-01 00:01:50 +1100 | [diff] [blame] | 110 | return false; |
| 111 | } |
Jan Engelhardt | e1931b7 | 2007-07-07 22:16:26 -0700 | [diff] [blame] | 112 | return true; |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 113 | } |
| 114 | |
Yasuyuki Kozakai | 11078c3 | 2006-12-12 00:29:02 -0800 | [diff] [blame] | 115 | static void |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 116 | connsecmark_tg_destroy(const struct xt_target *target, void *targinfo) |
Yasuyuki Kozakai | 11078c3 | 2006-12-12 00:29:02 -0800 | [diff] [blame] | 117 | { |
| 118 | nf_ct_l3proto_module_put(target->family); |
| 119 | } |
| 120 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 121 | static struct xt_target connsecmark_tg_reg[] __read_mostly = { |
Patrick McHardy | 4470bbc | 2006-08-22 00:34:04 -0700 | [diff] [blame] | 122 | { |
| 123 | .name = "CONNSECMARK", |
| 124 | .family = AF_INET, |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 125 | .checkentry = connsecmark_tg_check, |
| 126 | .destroy = connsecmark_tg_destroy, |
| 127 | .target = connsecmark_tg, |
Patrick McHardy | 4470bbc | 2006-08-22 00:34:04 -0700 | [diff] [blame] | 128 | .targetsize = sizeof(struct xt_connsecmark_target_info), |
| 129 | .table = "mangle", |
| 130 | .me = THIS_MODULE, |
| 131 | }, |
| 132 | { |
| 133 | .name = "CONNSECMARK", |
| 134 | .family = AF_INET6, |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 135 | .checkentry = connsecmark_tg_check, |
| 136 | .destroy = connsecmark_tg_destroy, |
| 137 | .target = connsecmark_tg, |
Patrick McHardy | 4470bbc | 2006-08-22 00:34:04 -0700 | [diff] [blame] | 138 | .targetsize = sizeof(struct xt_connsecmark_target_info), |
| 139 | .table = "mangle", |
| 140 | .me = THIS_MODULE, |
| 141 | }, |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 142 | }; |
| 143 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 144 | static int __init connsecmark_tg_init(void) |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 145 | { |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 146 | return xt_register_targets(connsecmark_tg_reg, |
| 147 | ARRAY_SIZE(connsecmark_tg_reg)); |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 148 | } |
| 149 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 150 | static void __exit connsecmark_tg_exit(void) |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 151 | { |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 152 | xt_unregister_targets(connsecmark_tg_reg, |
| 153 | ARRAY_SIZE(connsecmark_tg_reg)); |
James Morris | 100468e9 | 2006-06-09 00:32:39 -0700 | [diff] [blame] | 154 | } |
| 155 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 156 | module_init(connsecmark_tg_init); |
| 157 | module_exit(connsecmark_tg_exit); |