Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * iptables module to match IP address ranges |
| 3 | * |
| 4 | * (C) 2003 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> |
| 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 | #include <linux/module.h> |
| 11 | #include <linux/skbuff.h> |
| 12 | #include <linux/ip.h> |
| 13 | #include <linux/netfilter_ipv4/ip_tables.h> |
| 14 | #include <linux/netfilter_ipv4/ipt_iprange.h> |
| 15 | |
| 16 | MODULE_LICENSE("GPL"); |
| 17 | MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>"); |
| 18 | MODULE_DESCRIPTION("iptables arbitrary IP range match module"); |
| 19 | |
| 20 | #if 0 |
| 21 | #define DEBUGP printk |
| 22 | #else |
| 23 | #define DEBUGP(format, args...) |
| 24 | #endif |
| 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, |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 31 | int offset, unsigned int protoff, int *hotdrop) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | { |
| 33 | const struct ipt_iprange_info *info = matchinfo; |
| 34 | const struct iphdr *iph = skb->nh.iph; |
| 35 | |
| 36 | if (info->flags & IPRANGE_SRC) { |
| 37 | if (((ntohl(iph->saddr) < ntohl(info->src.min_ip)) |
| 38 | || (ntohl(iph->saddr) > ntohl(info->src.max_ip))) |
| 39 | ^ !!(info->flags & IPRANGE_SRC_INV)) { |
| 40 | DEBUGP("src IP %u.%u.%u.%u NOT in range %s" |
| 41 | "%u.%u.%u.%u-%u.%u.%u.%u\n", |
| 42 | NIPQUAD(iph->saddr), |
| 43 | info->flags & IPRANGE_SRC_INV ? "(INV) " : "", |
| 44 | NIPQUAD(info->src.min_ip), |
| 45 | NIPQUAD(info->src.max_ip)); |
| 46 | return 0; |
| 47 | } |
| 48 | } |
| 49 | if (info->flags & IPRANGE_DST) { |
| 50 | if (((ntohl(iph->daddr) < ntohl(info->dst.min_ip)) |
| 51 | || (ntohl(iph->daddr) > ntohl(info->dst.max_ip))) |
| 52 | ^ !!(info->flags & IPRANGE_DST_INV)) { |
| 53 | DEBUGP("dst IP %u.%u.%u.%u NOT in range %s" |
| 54 | "%u.%u.%u.%u-%u.%u.%u.%u\n", |
| 55 | NIPQUAD(iph->daddr), |
| 56 | info->flags & IPRANGE_DST_INV ? "(INV) " : "", |
| 57 | NIPQUAD(info->dst.min_ip), |
| 58 | NIPQUAD(info->dst.max_ip)); |
| 59 | return 0; |
| 60 | } |
| 61 | } |
| 62 | return 1; |
| 63 | } |
| 64 | |
| 65 | static int check(const char *tablename, |
Harald Welte | 2e4e6a1 | 2006-01-12 13:30:04 -0800 | [diff] [blame] | 66 | const void *inf, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 67 | void *matchinfo, |
| 68 | unsigned int matchsize, |
| 69 | unsigned int hook_mask) |
| 70 | { |
| 71 | /* verify size */ |
| 72 | if (matchsize != IPT_ALIGN(sizeof(struct ipt_iprange_info))) |
| 73 | return 0; |
| 74 | |
| 75 | return 1; |
| 76 | } |
| 77 | |
| 78 | static struct ipt_match iprange_match = |
| 79 | { |
| 80 | .list = { NULL, NULL }, |
| 81 | .name = "iprange", |
| 82 | .match = &match, |
| 83 | .checkentry = &check, |
| 84 | .destroy = NULL, |
| 85 | .me = THIS_MODULE |
| 86 | }; |
| 87 | |
| 88 | static int __init init(void) |
| 89 | { |
| 90 | return ipt_register_match(&iprange_match); |
| 91 | } |
| 92 | |
| 93 | static void __exit fini(void) |
| 94 | { |
| 95 | ipt_unregister_match(&iprange_match); |
| 96 | } |
| 97 | |
| 98 | module_init(init); |
| 99 | module_exit(fini); |