Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* Kernel module to match MAC address parameters. */ |
| 2 | |
| 3 | /* (C) 1999-2001 Paul `Rusty' Russell |
| 4 | * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org> |
| 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> |
| 13 | #include <linux/if_ether.h> |
Kris Katterjohn | d3f4a68 | 2006-01-09 16:01:43 -0800 | [diff] [blame] | 14 | #include <linux/etherdevice.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 16 | #include <linux/netfilter_ipv4.h> |
| 17 | #include <linux/netfilter/xt_mac.h> |
| 18 | #include <linux/netfilter/x_tables.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | |
| 20 | MODULE_LICENSE("GPL"); |
| 21 | MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>"); |
| 22 | MODULE_DESCRIPTION("iptables mac matching module"); |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 23 | MODULE_ALIAS("ipt_mac"); |
| 24 | MODULE_ALIAS("ip6t_mac"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | |
| 26 | static int |
| 27 | match(const struct sk_buff *skb, |
| 28 | const struct net_device *in, |
| 29 | const struct net_device *out, |
| 30 | const void *matchinfo, |
| 31 | int offset, |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 32 | unsigned int protoff, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | int *hotdrop) |
| 34 | { |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 35 | const struct xt_mac_info *info = matchinfo; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | |
| 37 | /* Is mac pointer valid? */ |
| 38 | return (skb->mac.raw >= skb->head |
| 39 | && (skb->mac.raw + ETH_HLEN) <= skb->data |
| 40 | /* If so, compare... */ |
Kris Katterjohn | d3f4a68 | 2006-01-09 16:01:43 -0800 | [diff] [blame] | 41 | && ((!compare_ether_addr(eth_hdr(skb)->h_source, info->srcaddr)) |
| 42 | ^ info->invert)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | } |
| 44 | |
| 45 | static int |
| 46 | ipt_mac_checkentry(const char *tablename, |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 47 | const void *inf, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | void *matchinfo, |
| 49 | unsigned int matchsize, |
| 50 | unsigned int hook_mask) |
| 51 | { |
| 52 | /* FORWARD isn't always valid, but it's nice to be able to do --RR */ |
| 53 | if (hook_mask |
| 54 | & ~((1 << NF_IP_PRE_ROUTING) | (1 << NF_IP_LOCAL_IN) |
| 55 | | (1 << NF_IP_FORWARD))) { |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 56 | printk("xt_mac: only valid for PRE_ROUTING, LOCAL_IN or FORWARD.\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | return 0; |
| 58 | } |
| 59 | |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 60 | if (matchsize != XT_ALIGN(sizeof(struct xt_mac_info))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | return 0; |
| 62 | |
| 63 | return 1; |
| 64 | } |
| 65 | |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 66 | static struct xt_match mac_match = { |
| 67 | .name = "mac", |
| 68 | .match = &match, |
| 69 | .checkentry = &ipt_mac_checkentry, |
| 70 | .me = THIS_MODULE, |
| 71 | }; |
| 72 | static struct xt_match mac6_match = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | .name = "mac", |
| 74 | .match = &match, |
| 75 | .checkentry = &ipt_mac_checkentry, |
| 76 | .me = THIS_MODULE, |
| 77 | }; |
| 78 | |
| 79 | static int __init init(void) |
| 80 | { |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 81 | int ret; |
| 82 | ret = xt_register_match(AF_INET, &mac_match); |
| 83 | if (ret) |
| 84 | return ret; |
| 85 | |
| 86 | ret = xt_register_match(AF_INET6, &mac6_match); |
| 87 | if (ret) |
| 88 | xt_unregister_match(AF_INET, &mac_match); |
| 89 | |
| 90 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | } |
| 92 | |
| 93 | static void __exit fini(void) |
| 94 | { |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 95 | xt_unregister_match(AF_INET, &mac_match); |
| 96 | xt_unregister_match(AF_INET6, &mac6_match); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | } |
| 98 | |
| 99 | module_init(init); |
| 100 | module_exit(fini); |