Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* Kernel module to match EUI64 address parameters. */ |
| 2 | |
| 3 | /* (C) 2001-2002 Andras Kis-Szabo <kisza@sch.bme.hu> |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License version 2 as |
| 7 | * published by the Free Software Foundation. |
| 8 | */ |
| 9 | |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/skbuff.h> |
| 12 | #include <linux/ipv6.h> |
| 13 | #include <linux/if_ether.h> |
| 14 | |
Jan Engelhardt | 6709dbb | 2007-02-07 15:11:19 -0800 | [diff] [blame] | 15 | #include <linux/netfilter/x_tables.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | #include <linux/netfilter_ipv6/ip6_tables.h> |
| 17 | |
| 18 | MODULE_DESCRIPTION("IPv6 EUI64 address checking match"); |
| 19 | MODULE_LICENSE("GPL"); |
| 20 | MODULE_AUTHOR("Andras Kis-Szabo <kisza@sch.bme.hu>"); |
| 21 | |
| 22 | static int |
| 23 | match(const struct sk_buff *skb, |
| 24 | const struct net_device *in, |
| 25 | const struct net_device *out, |
Patrick McHardy | c498673 | 2006-03-20 18:02:56 -0800 | [diff] [blame] | 26 | const struct xt_match *match, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | const void *matchinfo, |
| 28 | int offset, |
| 29 | unsigned int protoff, |
| 30 | int *hotdrop) |
| 31 | { |
Yasuyuki Kozakai | f0daaa6 | 2006-01-17 02:39:39 -0800 | [diff] [blame] | 32 | unsigned char eui64[8]; |
| 33 | int i = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | |
Yasuyuki Kozakai | f0daaa6 | 2006-01-17 02:39:39 -0800 | [diff] [blame] | 35 | if (!(skb->mac.raw >= skb->head && |
| 36 | (skb->mac.raw + ETH_HLEN) <= skb->data) && |
| 37 | offset != 0) { |
| 38 | *hotdrop = 1; |
| 39 | return 0; |
| 40 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | |
Yasuyuki Kozakai | f0daaa6 | 2006-01-17 02:39:39 -0800 | [diff] [blame] | 42 | memset(eui64, 0, sizeof(eui64)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | |
Alexey Dobriyan | d8fd0a7 | 2006-05-16 15:24:41 -0700 | [diff] [blame] | 44 | if (eth_hdr(skb)->h_proto == htons(ETH_P_IPV6)) { |
Yasuyuki Kozakai | f0daaa6 | 2006-01-17 02:39:39 -0800 | [diff] [blame] | 45 | if (skb->nh.ipv6h->version == 0x6) { |
| 46 | memcpy(eui64, eth_hdr(skb)->h_source, 3); |
| 47 | memcpy(eui64 + 5, eth_hdr(skb)->h_source + 3, 3); |
| 48 | eui64[3] = 0xff; |
| 49 | eui64[4] = 0xfe; |
| 50 | eui64[0] |= 0x02; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | |
Yasuyuki Kozakai | f0daaa6 | 2006-01-17 02:39:39 -0800 | [diff] [blame] | 52 | i = 0; |
| 53 | while ((skb->nh.ipv6h->saddr.s6_addr[8+i] == eui64[i]) |
| 54 | && (i < 8)) |
| 55 | i++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 56 | |
Yasuyuki Kozakai | f0daaa6 | 2006-01-17 02:39:39 -0800 | [diff] [blame] | 57 | if (i == 8) |
| 58 | return 1; |
| 59 | } |
| 60 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | |
Yasuyuki Kozakai | f0daaa6 | 2006-01-17 02:39:39 -0800 | [diff] [blame] | 62 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | } |
| 64 | |
Jan Engelhardt | 6709dbb | 2007-02-07 15:11:19 -0800 | [diff] [blame] | 65 | static struct xt_match eui64_match = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | .name = "eui64", |
Jan Engelhardt | 6709dbb | 2007-02-07 15:11:19 -0800 | [diff] [blame] | 67 | .family = AF_INET6, |
Patrick McHardy | 7f93971 | 2006-03-20 18:01:43 -0800 | [diff] [blame] | 68 | .match = match, |
| 69 | .matchsize = sizeof(int), |
| 70 | .hooks = (1 << NF_IP6_PRE_ROUTING) | (1 << NF_IP6_LOCAL_IN) | |
| 71 | (1 << NF_IP6_FORWARD), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 72 | .me = THIS_MODULE, |
| 73 | }; |
| 74 | |
Andrew Morton | 65b4b4e | 2006-03-28 16:37:06 -0800 | [diff] [blame] | 75 | static int __init ip6t_eui64_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | { |
Jan Engelhardt | 6709dbb | 2007-02-07 15:11:19 -0800 | [diff] [blame] | 77 | return xt_register_match(&eui64_match); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | } |
| 79 | |
Andrew Morton | 65b4b4e | 2006-03-28 16:37:06 -0800 | [diff] [blame] | 80 | static void __exit ip6t_eui64_fini(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 81 | { |
Jan Engelhardt | 6709dbb | 2007-02-07 15:11:19 -0800 | [diff] [blame] | 82 | xt_unregister_match(&eui64_match); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 83 | } |
| 84 | |
Andrew Morton | 65b4b4e | 2006-03-28 16:37:06 -0800 | [diff] [blame] | 85 | module_init(ip6t_eui64_init); |
| 86 | module_exit(ip6t_eui64_fini); |