/* * (C) 2000-2001 Svenning Soerensen <svenning@post5.tele.dk> * Copyright (c) 2011 Patrick McHardy <kaber@trash.net> * * 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/ip.h>#include <linux/kernel.h>#include <linux/module.h>#include <linux/netdevice.h>#include <linux/ipv6.h>#include <linux/netfilter.h>#include <linux/netfilter_ipv4.h>#include <linux/netfilter_ipv6.h>#include <linux/netfilter/x_tables.h>#include <net/netfilter/nf_nat.h> static unsigned intnetmap_tg6(struct sk_buff *skb, const struct xt_action_param *par){	const struct nf_nat_range *range = par->targinfo;	struct nf_nat_range newrange;	struct nf_conn *ct;	enum ip_conntrack_info ctinfo;	union nf_inet_addr new_addr, netmask;	unsigned int i; 	ct = nf_ct_get(skb, &ctinfo);	for (i = 0; i < ARRAY_SIZE(range->min_addr.ip6); i++)		netmask.ip6[i] = ~(range->min_addr.ip6[i] ^				   range->max_addr.ip6[i]); 	if (par->hooknum == NF_INET_PRE_ROUTING ||	    par->hooknum == NF_INET_LOCAL_OUT)		new_addr.in6 = ipv6_hdr(skb)->daddr;	else		new_addr.in6 = ipv6_hdr(skb)->saddr; 	for (i = 0; i < ARRAY_SIZE(new_addr.ip6); i++) {		new_addr.ip6[i] &= ~netmask.ip6[i];		new_addr.ip6[i] |= range->min_addr.ip6[i] &				   netmask.ip6[i];	} 	newrange.flags	= range->flags | NF_NAT_RANGE_MAP_IPS;	newrange.min_addr	= new_addr;	newrange.max_addr	= new_addr;	newrange.min_proto	= range->min_proto;	newrange.max_proto	= range->max_proto; 	return nf_nat_setup_info(ct, &newrange, HOOK2MANIP(par->hooknum));} static int netmap_tg6_checkentry(const struct xt_tgchk_param *par){	const struct nf_nat_range *range = par->targinfo; 	if (!(range->flags & NF_NAT_RANGE_MAP_IPS))		return -EINVAL;	return 0;} static unsigned intnetmap_tg4(struct sk_buff *skb, const struct xt_action_param *par){	struct nf_conn *ct;	enum ip_conntrack_info ctinfo;	__be32 new_ip, netmask;	const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo;	struct nf_nat_range newrange; 	NF_CT_ASSERT(par->hooknum == NF_INET_PRE_ROUTING ||		     par->hooknum == NF_INET_POST_ROUTING ||		     par->hooknum == NF_INET_LOCAL_OUT ||		     par->hooknum == NF_INET_LOCAL_IN);	ct = nf_ct_get(skb, &ctinfo); 	netmask = ~(mr->range[0].min_ip ^ mr->range[0].max_ip); 	if (par->hooknum == NF_INET_PRE_ROUTING ||	    par->hooknum == NF_INET_LOCAL_OUT)		new_ip = ip_hdr(skb)->daddr & ~netmask;	else		new_ip = ip_hdr(skb)->saddr & ~netmask;	new_ip |= mr->range[0].min_ip & netmask; 	memset(&newrange.min_addr, 0, sizeof(newrange.min_addr));	memset(&newrange.max_addr, 0, sizeof(newrange.max_addr));	newrange.flags	     = mr->range[0].flags | NF_NAT_RANGE_MAP_IPS;	newrange.min_addr.ip = new_ip;	newrange.max_addr.ip = new_ip;	newrange.min_proto   = mr->range[0].min;	newrange.max_proto   = mr->range[0].max; 	/* Hand modified range to generic setup. */	return nf_nat_setup_info(ct, &newrange, HOOK2MANIP(par->hooknum));} static int netmap_tg4_check(const struct xt_tgchk_param *par){	const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo; 	if (!(mr->range[0].flags & NF_NAT_RANGE_MAP_IPS)) {		pr_debug("bad MAP_IPS.\n");		return -EINVAL;	}	if (mr->rangesize != 1) {		pr_debug("bad rangesize %u.\n", mr->rangesize);		return -EINVAL;	}	return 0;} static struct xt_target netmap_tg_reg[] __read_mostly = {	{		.name       = "NETMAP",		.family     = NFPROTO_IPV6,		.revision   = 0,		.target     = netmap_tg6,		.targetsize = sizeof(struct nf_nat_range),		.table      = "nat",		.hooks      = (1 << NF_INET_PRE_ROUTING) |		              (1 << NF_INET_POST_ROUTING) |		              (1 << NF_INET_LOCAL_OUT) |		              (1 << NF_INET_LOCAL_IN),		.checkentry = netmap_tg6_checkentry,		.me         = THIS_MODULE,	},	{		.name       = "NETMAP",		.family     = NFPROTO_IPV4,		.revision   = 0,		.target     = netmap_tg4,		.targetsize = sizeof(struct nf_nat_ipv4_multi_range_compat),		.table      = "nat",		.hooks      = (1 << NF_INET_PRE_ROUTING) |		              (1 << NF_INET_POST_ROUTING) |		              (1 << NF_INET_LOCAL_OUT) |		              (1 << NF_INET_LOCAL_IN),		.checkentry = netmap_tg4_check,		.me         = THIS_MODULE,	},}; static int __init netmap_tg_init(void){	return xt_register_targets(netmap_tg_reg, ARRAY_SIZE(netmap_tg_reg));} static void netmap_tg_exit(void){	xt_unregister_targets(netmap_tg_reg, ARRAY_SIZE(netmap_tg_reg));} module_init(netmap_tg_init);module_exit(netmap_tg_exit); MODULE_LICENSE("GPL");MODULE_DESCRIPTION("Xtables: 1:1 NAT mapping of subnets");MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");MODULE_ALIAS("ip6t_NETMAP");MODULE_ALIAS("ipt_NETMAP");