From ed72d9e294a66fce8f4b4a2f6c8c011b22f1a87c Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Sun, 26 Aug 2012 19:14:18 +0200 Subject: [PATCH] netfilter: ip6tables: add NETMAP target Signed-off-by: Patrick McHardy --- net/ipv6/netfilter/Kconfig | 10 +++++ net/ipv6/netfilter/Makefile | 1 + net/ipv6/netfilter/ip6t_NETMAP.c | 94 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 105 insertions(+) create mode 100644 net/ipv6/netfilter/ip6t_NETMAP.c diff --git a/net/ipv6/netfilter/Kconfig b/net/ipv6/netfilter/Kconfig index 585590f..7bdf73b 100644 --- a/net/ipv6/netfilter/Kconfig +++ b/net/ipv6/netfilter/Kconfig @@ -156,6 +156,16 @@ config IP6_NF_TARGET_MASQUERADE To compile it as a module, choose M here. If unsure, say N. +config IP6_NF_TARGET_NETMAP + tristate "NETMAP target support" + depends on NF_NAT_IPV6 + help + NETMAP is an implementation of static 1:1 NAT mapping of network + addresses. It maps the network address part, while keeping the host + address part intact. + + To compile it as a module, choose M here. If unsure, say N. + config IP6_NF_TARGET_REDIRECT tristate "REDIRECT target support" depends on NF_NAT_IPV6 diff --git a/net/ipv6/netfilter/Makefile b/net/ipv6/netfilter/Makefile index e30a531..0864ce6 100644 --- a/net/ipv6/netfilter/Makefile +++ b/net/ipv6/netfilter/Makefile @@ -35,5 +35,6 @@ obj-$(CONFIG_IP6_NF_MATCH_RT) += ip6t_rt.o # targets obj-$(CONFIG_IP6_NF_TARGET_MASQUERADE) += ip6t_MASQUERADE.o +obj-$(CONFIG_IP6_NF_TARGET_NETMAP) += ip6t_NETMAP.o obj-$(CONFIG_IP6_NF_TARGET_REDIRECT) += ip6t_REDIRECT.o obj-$(CONFIG_IP6_NF_TARGET_REJECT) += ip6t_REJECT.o diff --git a/net/ipv6/netfilter/ip6t_NETMAP.c b/net/ipv6/netfilter/ip6t_NETMAP.c new file mode 100644 index 0000000..4f3bf36 --- /dev/null +++ b/net/ipv6/netfilter/ip6t_NETMAP.c @@ -0,0 +1,94 @@ +/* + * 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 Svenning Soerensen's IPv4 NETMAP target. Development of IPv6 + * NAT funded by Astaro. + */ + +#include +#include +#include +#include +#include +#include +#include + +static unsigned int +netmap_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 struct xt_target netmap_tg6_reg __read_mostly = { + .name = "NETMAP", + .family = NFPROTO_IPV6, + .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, +}; + +static int __init netmap_tg6_init(void) +{ + return xt_register_target(&netmap_tg6_reg); +} + +static void netmap_tg6_exit(void) +{ + xt_unregister_target(&netmap_tg6_reg); +} + +module_init(netmap_tg6_init); +module_exit(netmap_tg6_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Xtables: 1:1 NAT mapping of IPv6 subnets"); +MODULE_AUTHOR("Patrick McHardy "); -- 2.7.4