Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / net / ipv6 / netfilter / nf_nat_masquerade_ipv6.c

diff --git a/kernel/net/ipv6/netfilter/nf_nat_masquerade_ipv6.c b/kernel/net/ipv6/netfilter/nf_nat_masquerade_ipv6.c
new file mode 100644 (file)
index 0000000..7745609
--- /dev/null
+++ b/kernel/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>");