| /* |
| * xt_iprange - Netfilter module to match IP address ranges |
| * |
| * (C) 2003 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> |
| * (C) CC Computer Consultants GmbH, 2008 |
| * |
| * 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. |
| */ |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| #include <linux/module.h> |
| #include <linux/skbuff.h> |
| #include <linux/ip.h> |
| #include <linux/ipv6.h> |
| #include <linux/netfilter/x_tables.h> |
| #include <linux/netfilter/xt_iprange.h> |
| |
| static bool |
| iprange_mt4(const struct sk_buff *skb, struct xt_action_param *par) |
| { |
| const struct xt_iprange_mtinfo *info = par->matchinfo; |
| const struct iphdr *iph = ip_hdr(skb); |
| bool m; |
| |
| if (info->flags & IPRANGE_SRC) { |
| m = ntohl(iph->saddr) < ntohl(info->src_min.ip); |
| m |= ntohl(iph->saddr) > ntohl(info->src_max.ip); |
| m ^= !!(info->flags & IPRANGE_SRC_INV); |
| if (m) { |
| pr_debug("src IP %pI4 NOT in range %s%pI4-%pI4\n", |
| &iph->saddr, |
| (info->flags & IPRANGE_SRC_INV) ? "(INV) " : "", |
| &info->src_min.ip, |
| &info->src_max.ip); |
| return false; |
| } |
| } |
| if (info->flags & IPRANGE_DST) { |
| m = ntohl(iph->daddr) < ntohl(info->dst_min.ip); |
| m |= ntohl(iph->daddr) > ntohl(info->dst_max.ip); |
| m ^= !!(info->flags & IPRANGE_DST_INV); |
| if (m) { |
| pr_debug("dst IP %pI4 NOT in range %s%pI4-%pI4\n", |
| &iph->daddr, |
| (info->flags & IPRANGE_DST_INV) ? "(INV) " : "", |
| &info->dst_min.ip, |
| &info->dst_max.ip); |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| static inline int |
| iprange_ipv6_lt(const struct in6_addr *a, const struct in6_addr *b) |
| { |
| unsigned int i; |
| |
| for (i = 0; i < 4; ++i) { |
| if (a->s6_addr32[i] != b->s6_addr32[i]) |
| return ntohl(a->s6_addr32[i]) < ntohl(b->s6_addr32[i]); |
| } |
| |
| return 0; |
| } |
| |
| static bool |
| iprange_mt6(const struct sk_buff *skb, struct xt_action_param *par) |
| { |
| const struct xt_iprange_mtinfo *info = par->matchinfo; |
| const struct ipv6hdr *iph = ipv6_hdr(skb); |
| bool m; |
| |
| if (info->flags & IPRANGE_SRC) { |
| m = iprange_ipv6_lt(&iph->saddr, &info->src_min.in6); |
| m |= iprange_ipv6_lt(&info->src_max.in6, &iph->saddr); |
| m ^= !!(info->flags & IPRANGE_SRC_INV); |
| if (m) { |
| pr_debug("src IP %pI6 NOT in range %s%pI6-%pI6\n", |
| &iph->saddr, |
| (info->flags & IPRANGE_SRC_INV) ? "(INV) " : "", |
| &info->src_min.in6, |
| &info->src_max.in6); |
| return false; |
| } |
| } |
| if (info->flags & IPRANGE_DST) { |
| m = iprange_ipv6_lt(&iph->daddr, &info->dst_min.in6); |
| m |= iprange_ipv6_lt(&info->dst_max.in6, &iph->daddr); |
| m ^= !!(info->flags & IPRANGE_DST_INV); |
| if (m) { |
| pr_debug("dst IP %pI6 NOT in range %s%pI6-%pI6\n", |
| &iph->daddr, |
| (info->flags & IPRANGE_DST_INV) ? "(INV) " : "", |
| &info->dst_min.in6, |
| &info->dst_max.in6); |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| static struct xt_match iprange_mt_reg[] __read_mostly = { |
| { |
| .name = "iprange", |
| .revision = 1, |
| .family = NFPROTO_IPV4, |
| .match = iprange_mt4, |
| .matchsize = sizeof(struct xt_iprange_mtinfo), |
| .me = THIS_MODULE, |
| }, |
| { |
| .name = "iprange", |
| .revision = 1, |
| .family = NFPROTO_IPV6, |
| .match = iprange_mt6, |
| .matchsize = sizeof(struct xt_iprange_mtinfo), |
| .me = THIS_MODULE, |
| }, |
| }; |
| |
| static int __init iprange_mt_init(void) |
| { |
| return xt_register_matches(iprange_mt_reg, ARRAY_SIZE(iprange_mt_reg)); |
| } |
| |
| static void __exit iprange_mt_exit(void) |
| { |
| xt_unregister_matches(iprange_mt_reg, ARRAY_SIZE(iprange_mt_reg)); |
| } |
| |
| module_init(iprange_mt_init); |
| module_exit(iprange_mt_exit); |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>"); |
| MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>"); |
| MODULE_DESCRIPTION("Xtables: arbitrary IPv4 range matching"); |
| MODULE_ALIAS("ipt_iprange"); |
| MODULE_ALIAS("ip6t_iprange"); |