| /* |
| * iptables module to match IP address ranges |
| * |
| * (C) 2003 Jozsef Kadlecsik <kadlec@blackhole.kfki.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/ip.h> |
| #include <linux/netfilter/x_tables.h> |
| #include <linux/netfilter_ipv4/ipt_iprange.h> |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>"); |
| MODULE_DESCRIPTION("iptables arbitrary IP range match module"); |
| |
| static bool |
| 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, bool *hotdrop) |
| { |
| const struct ipt_iprange_info *info = matchinfo; |
| const struct iphdr *iph = ip_hdr(skb); |
| |
| if (info->flags & IPRANGE_SRC) { |
| if ((ntohl(iph->saddr) < ntohl(info->src.min_ip) |
| || ntohl(iph->saddr) > ntohl(info->src.max_ip)) |
| ^ !!(info->flags & IPRANGE_SRC_INV)) { |
| pr_debug("src IP %u.%u.%u.%u NOT in range %s" |
| "%u.%u.%u.%u-%u.%u.%u.%u\n", |
| NIPQUAD(iph->saddr), |
| info->flags & IPRANGE_SRC_INV ? "(INV) " : "", |
| NIPQUAD(info->src.min_ip), |
| NIPQUAD(info->src.max_ip)); |
| return false; |
| } |
| } |
| if (info->flags & IPRANGE_DST) { |
| if ((ntohl(iph->daddr) < ntohl(info->dst.min_ip) |
| || ntohl(iph->daddr) > ntohl(info->dst.max_ip)) |
| ^ !!(info->flags & IPRANGE_DST_INV)) { |
| pr_debug("dst IP %u.%u.%u.%u NOT in range %s" |
| "%u.%u.%u.%u-%u.%u.%u.%u\n", |
| NIPQUAD(iph->daddr), |
| info->flags & IPRANGE_DST_INV ? "(INV) " : "", |
| NIPQUAD(info->dst.min_ip), |
| NIPQUAD(info->dst.max_ip)); |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| static struct xt_match iprange_match __read_mostly = { |
| .name = "iprange", |
| .family = AF_INET, |
| .match = match, |
| .matchsize = sizeof(struct ipt_iprange_info), |
| .me = THIS_MODULE |
| }; |
| |
| static int __init ipt_iprange_init(void) |
| { |
| return xt_register_match(&iprange_match); |
| } |
| |
| static void __exit ipt_iprange_fini(void) |
| { |
| xt_unregister_match(&iprange_match); |
| } |
| |
| module_init(ipt_iprange_init); |
| module_exit(ipt_iprange_fini); |