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Release 4.14 net/netfilter/nf_nat_redirect.c

Directory: net/netfilter
 * (C) 1999-2001 Paul `Rusty' Russell
 * (C) 2002-2006 Netfilter Core Team <>
 * Copyright (c) 2011 Patrick McHardy <>
 * 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.
 * Based on Rusty Russell's IPv4 REDIRECT target. Development of IPv6
 * NAT funded by Astaro.

#include <linux/if.h>
#include <linux/inetdevice.h>
#include <linux/ip.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/netfilter.h>
#include <linux/types.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv6.h>
#include <linux/netfilter/x_tables.h>
#include <net/addrconf.h>
#include <net/checksum.h>
#include <net/protocol.h>
#include <net/netfilter/nf_nat.h>
#include <net/netfilter/nf_nat_redirect.h>

unsigned int nf_nat_redirect_ipv4(struct sk_buff *skb, const struct nf_nat_ipv4_multi_range_compat *mr, unsigned int hooknum) { struct nf_conn *ct; enum ip_conntrack_info ctinfo; __be32 newdst; struct nf_nat_range newrange; WARN_ON(hooknum != NF_INET_PRE_ROUTING && hooknum != NF_INET_LOCAL_OUT); ct = nf_ct_get(skb, &ctinfo); WARN_ON(!(ct && (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED))); /* Local packets: make them go to loopback */ if (hooknum == NF_INET_LOCAL_OUT) { newdst = htonl(0x7F000001); } else { struct in_device *indev; struct in_ifaddr *ifa; newdst = 0; rcu_read_lock(); indev = __in_dev_get_rcu(skb->dev); if (indev && indev->ifa_list) { ifa = indev->ifa_list; newdst = ifa->ifa_local; } rcu_read_unlock(); if (!newdst) return NF_DROP; } /* Transfer from original range. */ 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 = newdst; newrange.max_addr.ip = newdst; 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, NF_NAT_MANIP_DST); }


Arturo Borrero Gonzalez24695.35%133.33%
Varsha Rao83.10%133.33%
Munehisa Kamata41.55%133.33%

EXPORT_SYMBOL_GPL(nf_nat_redirect_ipv4); static const struct in6_addr loopback_addr = IN6ADDR_LOOPBACK_INIT;
unsigned int nf_nat_redirect_ipv6(struct sk_buff *skb, const struct nf_nat_range *range, unsigned int hooknum) { struct nf_nat_range newrange; struct in6_addr newdst; enum ip_conntrack_info ctinfo; struct nf_conn *ct; ct = nf_ct_get(skb, &ctinfo); if (hooknum == NF_INET_LOCAL_OUT) { newdst = loopback_addr; } else { struct inet6_dev *idev; struct inet6_ifaddr *ifa; bool addr = false; rcu_read_lock(); idev = __in6_dev_get(skb->dev); if (idev != NULL) { read_lock_bh(&idev->lock); list_for_each_entry(ifa, &idev->addr_list, if_list) { newdst = ifa->addr; addr = true; break; } read_unlock_bh(&idev->lock); } rcu_read_unlock(); if (!addr) return NF_DROP; } newrange.flags = range->flags | NF_NAT_RANGE_MAP_IPS; newrange.min_addr.in6 = newdst; newrange.max_addr.in6 = newdst; newrange.min_proto = range->min_proto; newrange.max_proto = range->max_proto; return nf_nat_setup_info(ct, &newrange, NF_NAT_MANIP_DST); }


Pablo Neira Ayuso18391.96%150.00%
Liping Zhang168.04%150.00%

EXPORT_SYMBOL_GPL(nf_nat_redirect_ipv6); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Patrick McHardy <>");

Overall Contributors

Arturo Borrero Gonzalez30657.30%120.00%
Pablo Neira Ayuso20037.45%120.00%
Liping Zhang163.00%120.00%
Varsha Rao81.50%120.00%
Munehisa Kamata40.75%120.00%
Directory: net/netfilter
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