| /* |
| * 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_ipv4/ip_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"); |
| |
| #if 0 |
| #define DEBUGP printk |
| #else |
| #define DEBUGP(format, args...) |
| #endif |
| |
| static int |
| match(const struct sk_buff *skb, |
| const struct net_device *in, |
| const struct net_device *out, |
| const void *matchinfo, |
| int offset, int *hotdrop) |
| { |
| const struct ipt_iprange_info *info = matchinfo; |
| const struct iphdr *iph = skb->nh.iph; |
| |
| 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)) { |
| DEBUGP("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 0; |
| } |
| } |
| 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)) { |
| DEBUGP("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 0; |
| } |
| } |
| return 1; |
| } |
| |
| static int check(const char *tablename, |
| const struct ipt_ip *ip, |
| void *matchinfo, |
| unsigned int matchsize, |
| unsigned int hook_mask) |
| { |
| /* verify size */ |
| if (matchsize != IPT_ALIGN(sizeof(struct ipt_iprange_info))) |
| return 0; |
| |
| return 1; |
| } |
| |
| static struct ipt_match iprange_match = |
| { |
| .list = { NULL, NULL }, |
| .name = "iprange", |
| .match = &match, |
| .checkentry = &check, |
| .destroy = NULL, |
| .me = THIS_MODULE |
| }; |
| |
| static int __init init(void) |
| { |
| return ipt_register_match(&iprange_match); |
| } |
| |
| static void __exit fini(void) |
| { |
| ipt_unregister_match(&iprange_match); |
| } |
| |
| module_init(init); |
| module_exit(fini); |