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// SPDX-License-Identifier: GPL-2.0-only/* *	xt_iprange - Netfilter module to match IP address ranges * *	(C) 2003 Jozsef Kadlecsik <kadlec@netfilter.org> *	(C) CC Computer Consultants GmbH, 2008 */#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 booliprange_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)			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)			return false;	}	return true;} static inline intiprange_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 booliprange_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)			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)			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@netfilter.org>");MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>");MODULE_DESCRIPTION("Xtables: arbitrary IPv4 range matching");MODULE_ALIAS("ipt_iprange");MODULE_ALIAS("ip6t_iprange");