diff options
| -rw-r--r-- | include/net/netfilter/ipv6/nf_nat_masquerade.h | 10 | ||||
| -rw-r--r-- | net/ipv6/netfilter/Kconfig | 7 | ||||
| -rw-r--r-- | net/ipv6/netfilter/Makefile | 1 | ||||
| -rw-r--r-- | net/ipv6/netfilter/ip6t_MASQUERADE.c | 76 | ||||
| -rw-r--r-- | net/ipv6/netfilter/nf_nat_masquerade_ipv6.c | 120 |
5 files changed, 143 insertions, 71 deletions
diff --git a/include/net/netfilter/ipv6/nf_nat_masquerade.h b/include/net/netfilter/ipv6/nf_nat_masquerade.h new file mode 100644 index 0000000..0a13396 --- /dev/null +++ b/include/net/netfilter/ipv6/nf_nat_masquerade.h @@ -0,0 +1,10 @@ +#ifndef _NF_NAT_MASQUERADE_IPV6_H_ +#define _NF_NAT_MASQUERADE_IPV6_H_ + +unsigned int +nf_nat_masquerade_ipv6(struct sk_buff *skb, const struct nf_nat_range *range, + const struct net_device *out); +void nf_nat_masquerade_ipv6_register_notifier(void); +void nf_nat_masquerade_ipv6_unregister_notifier(void); + +#endif /* _NF_NAT_MASQUERADE_IPV6_H_ */ diff --git a/net/ipv6/netfilter/Kconfig b/net/ipv6/netfilter/Kconfig index ac93df1..6c8cfec 100644 --- a/net/ipv6/netfilter/Kconfig +++ b/net/ipv6/netfilter/Kconfig @@ -246,8 +246,15 @@ config NF_NAT_IPV6 if NF_NAT_IPV6 +config NF_NAT_MASQUERADE_IPV6 + tristate "IPv6 masquerade support" + help + This is the kernel functionality to provide NAT in the masquerade + flavour (automatic source address selection) for IPv6. + config IP6_NF_TARGET_MASQUERADE tristate "MASQUERADE target support" + select NF_NAT_MASQUERADE_IPV6 help Masquerading is a special case of NAT: all outgoing connections are changed to seem to come from a particular interface's address, and diff --git a/net/ipv6/netfilter/Makefile b/net/ipv6/netfilter/Makefile index c0b2631..89a0bd7 100644 --- a/net/ipv6/netfilter/Makefile +++ b/net/ipv6/netfilter/Makefile @@ -18,6 +18,7 @@ obj-$(CONFIG_NF_CONNTRACK_IPV6) += nf_conntrack_ipv6.o nf_nat_ipv6-y := nf_nat_l3proto_ipv6.o nf_nat_proto_icmpv6.o obj-$(CONFIG_NF_NAT_IPV6) += nf_nat_ipv6.o +obj-$(CONFIG_NF_NAT_MASQUERADE_IPV6) += nf_nat_masquerade_ipv6.o # defrag nf_defrag_ipv6-y := nf_defrag_ipv6_hooks.o nf_conntrack_reasm.o diff --git a/net/ipv6/netfilter/ip6t_MASQUERADE.c b/net/ipv6/netfilter/ip6t_MASQUERADE.c index 3e4e92d..7f9f45d 100644 --- a/net/ipv6/netfilter/ip6t_MASQUERADE.c +++ b/net/ipv6/netfilter/ip6t_MASQUERADE.c @@ -19,33 +19,12 @@ #include <net/netfilter/nf_nat.h> #include <net/addrconf.h> #include <net/ipv6.h> +#include <net/netfilter/ipv6/nf_nat_masquerade.h> static unsigned int masquerade_tg6(struct sk_buff *skb, const struct xt_action_param *par) { - const struct nf_nat_range *range = par->targinfo; - enum ip_conntrack_info ctinfo; - struct in6_addr src; - struct nf_conn *ct; - struct nf_nat_range newrange; - - ct = nf_ct_get(skb, &ctinfo); - NF_CT_ASSERT(ct && (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED || - ctinfo == IP_CT_RELATED_REPLY)); - - if (ipv6_dev_get_saddr(dev_net(par->out), par->out, - &ipv6_hdr(skb)->daddr, 0, &src) < 0) - return NF_DROP; - - nfct_nat(ct)->masq_index = par->out->ifindex; - - newrange.flags = range->flags | NF_NAT_RANGE_MAP_IPS; - newrange.min_addr.in6 = src; - newrange.max_addr.in6 = src; - newrange.min_proto = range->min_proto; - newrange.max_proto = range->max_proto; - - return nf_nat_setup_info(ct, &newrange, NF_NAT_MANIP_SRC); + return nf_nat_masquerade_ipv6(skb, par->targinfo, par->out); } static int masquerade_tg6_checkentry(const struct xt_tgchk_param *par) @@ -57,48 +36,6 @@ static int masquerade_tg6_checkentry(const struct xt_tgchk_param *par) return 0; } -static int device_cmp(struct nf_conn *ct, void *ifindex) -{ - const struct nf_conn_nat *nat = nfct_nat(ct); - - if (!nat) - return 0; - if (nf_ct_l3num(ct) != NFPROTO_IPV6) - return 0; - return nat->masq_index == (int)(long)ifindex; -} - -static int masq_device_event(struct notifier_block *this, - unsigned long event, void *ptr) -{ - const struct net_device *dev = netdev_notifier_info_to_dev(ptr); - struct net *net = dev_net(dev); - - if (event == NETDEV_DOWN) - nf_ct_iterate_cleanup(net, device_cmp, - (void *)(long)dev->ifindex, 0, 0); - - return NOTIFY_DONE; -} - -static struct notifier_block masq_dev_notifier = { - .notifier_call = masq_device_event, -}; - -static int masq_inet_event(struct notifier_block *this, - unsigned long event, void *ptr) -{ - struct inet6_ifaddr *ifa = ptr; - struct netdev_notifier_info info; - - netdev_notifier_info_init(&info, ifa->idev->dev); - return masq_device_event(this, event, &info); -} - -static struct notifier_block masq_inet_notifier = { - .notifier_call = masq_inet_event, -}; - static struct xt_target masquerade_tg6_reg __read_mostly = { .name = "MASQUERADE", .family = NFPROTO_IPV6, @@ -115,17 +52,14 @@ static int __init masquerade_tg6_init(void) int err; err = xt_register_target(&masquerade_tg6_reg); - if (err == 0) { - register_netdevice_notifier(&masq_dev_notifier); - register_inet6addr_notifier(&masq_inet_notifier); - } + if (err == 0) + nf_nat_masquerade_ipv6_register_notifier(); return err; } static void __exit masquerade_tg6_exit(void) { - unregister_inet6addr_notifier(&masq_inet_notifier); - unregister_netdevice_notifier(&masq_dev_notifier); + nf_nat_masquerade_ipv6_unregister_notifier(); xt_unregister_target(&masquerade_tg6_reg); } diff --git a/net/ipv6/netfilter/nf_nat_masquerade_ipv6.c b/net/ipv6/netfilter/nf_nat_masquerade_ipv6.c new file mode 100644 index 0000000..7745609 --- /dev/null +++ b/net/ipv6/netfilter/nf_nat_masquerade_ipv6.c @@ -0,0 +1,120 @@ +/* + * 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. + * + * Based on Rusty Russell's IPv6 MASQUERADE target. Development of IPv6 + * NAT funded by Astaro. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/atomic.h> +#include <linux/netdevice.h> +#include <linux/ipv6.h> +#include <linux/netfilter.h> +#include <linux/netfilter_ipv6.h> +#include <net/netfilter/nf_nat.h> +#include <net/addrconf.h> +#include <net/ipv6.h> +#include <net/netfilter/ipv6/nf_nat_masquerade.h> + +unsigned int +nf_nat_masquerade_ipv6(struct sk_buff *skb, const struct nf_nat_range *range, + const struct net_device *out) +{ + enum ip_conntrack_info ctinfo; + struct in6_addr src; + struct nf_conn *ct; + struct nf_nat_range newrange; + + ct = nf_ct_get(skb, &ctinfo); + NF_CT_ASSERT(ct && (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED || + ctinfo == IP_CT_RELATED_REPLY)); + + if (ipv6_dev_get_saddr(dev_net(out), out, + &ipv6_hdr(skb)->daddr, 0, &src) < 0) + return NF_DROP; + + nfct_nat(ct)->masq_index = out->ifindex; + + newrange.flags = range->flags | NF_NAT_RANGE_MAP_IPS; + newrange.min_addr.in6 = src; + newrange.max_addr.in6 = src; + newrange.min_proto = range->min_proto; + newrange.max_proto = range->max_proto; + + return nf_nat_setup_info(ct, &newrange, NF_NAT_MANIP_SRC); +} +EXPORT_SYMBOL_GPL(nf_nat_masquerade_ipv6); + +static int device_cmp(struct nf_conn *ct, void *ifindex) +{ + const struct nf_conn_nat *nat = nfct_nat(ct); + + if (!nat) + return 0; + if (nf_ct_l3num(ct) != NFPROTO_IPV6) + return 0; + return nat->masq_index == (int)(long)ifindex; +} + +static int masq_device_event(struct notifier_block *this, + unsigned long event, void *ptr) +{ + const struct net_device *dev = netdev_notifier_info_to_dev(ptr); + struct net *net = dev_net(dev); + + if (event == NETDEV_DOWN) + nf_ct_iterate_cleanup(net, device_cmp, + (void *)(long)dev->ifindex, 0, 0); + + return NOTIFY_DONE; +} + +static struct notifier_block masq_dev_notifier = { + .notifier_call = masq_device_event, +}; + +static int masq_inet_event(struct notifier_block *this, + unsigned long event, void *ptr) +{ + struct inet6_ifaddr *ifa = ptr; + struct netdev_notifier_info info; + + netdev_notifier_info_init(&info, ifa->idev->dev); + return masq_device_event(this, event, &info); +} + +static struct notifier_block masq_inet_notifier = { + .notifier_call = masq_inet_event, +}; + +static atomic_t masquerade_notifier_refcount = ATOMIC_INIT(0); + +void nf_nat_masquerade_ipv6_register_notifier(void) +{ + /* check if the notifier is already set */ + if (atomic_inc_return(&masquerade_notifier_refcount) > 1) + return; + + register_netdevice_notifier(&masq_dev_notifier); + register_inet6addr_notifier(&masq_inet_notifier); +} +EXPORT_SYMBOL_GPL(nf_nat_masquerade_ipv6_register_notifier); + +void nf_nat_masquerade_ipv6_unregister_notifier(void) +{ + /* check if the notifier still has clients */ + if (atomic_dec_return(&masquerade_notifier_refcount) > 0) + return; + + unregister_inet6addr_notifier(&masq_inet_notifier); + unregister_netdevice_notifier(&masq_dev_notifier); +} +EXPORT_SYMBOL_GPL(nf_nat_masquerade_ipv6_unregister_notifier); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); |
