| /* Kernel module to match EUI64 address parameters. */ |
| |
| /* (C) 2001-2002 Andras Kis-Szabo <kisza@sch.bme.hu> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/skbuff.h> |
| #include <linux/ipv6.h> |
| #include <linux/if_ether.h> |
| |
| #include <linux/netfilter/x_tables.h> |
| #include <linux/netfilter_ipv6/ip6_tables.h> |
| |
| MODULE_DESCRIPTION("IPv6 EUI64 address checking match"); |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Andras Kis-Szabo <kisza@sch.bme.hu>"); |
| |
| static int |
| match(const struct sk_buff *skb, |
| const struct net_device *in, |
| const struct net_device *out, |
| const struct xt_match *match, |
| const void *matchinfo, |
| int offset, |
| unsigned int protoff, |
| int *hotdrop) |
| { |
| unsigned char eui64[8]; |
| int i = 0; |
| |
| if (!(skb_mac_header(skb) >= skb->head && |
| (skb_mac_header(skb) + ETH_HLEN) <= skb->data) && |
| offset != 0) { |
| *hotdrop = 1; |
| return 0; |
| } |
| |
| memset(eui64, 0, sizeof(eui64)); |
| |
| if (eth_hdr(skb)->h_proto == htons(ETH_P_IPV6)) { |
| if (skb->nh.ipv6h->version == 0x6) { |
| memcpy(eui64, eth_hdr(skb)->h_source, 3); |
| memcpy(eui64 + 5, eth_hdr(skb)->h_source + 3, 3); |
| eui64[3] = 0xff; |
| eui64[4] = 0xfe; |
| eui64[0] |= 0x02; |
| |
| i = 0; |
| while ((skb->nh.ipv6h->saddr.s6_addr[8+i] == eui64[i]) |
| && (i < 8)) |
| i++; |
| |
| if (i == 8) |
| return 1; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static struct xt_match eui64_match = { |
| .name = "eui64", |
| .family = AF_INET6, |
| .match = match, |
| .matchsize = sizeof(int), |
| .hooks = (1 << NF_IP6_PRE_ROUTING) | (1 << NF_IP6_LOCAL_IN) | |
| (1 << NF_IP6_FORWARD), |
| .me = THIS_MODULE, |
| }; |
| |
| static int __init ip6t_eui64_init(void) |
| { |
| return xt_register_match(&eui64_match); |
| } |
| |
| static void __exit ip6t_eui64_fini(void) |
| { |
| xt_unregister_match(&eui64_match); |
| } |
| |
| module_init(ip6t_eui64_init); |
| module_exit(ip6t_eui64_fini); |