diff mbox

[net-next,02/02] net/ipv4: VTI support new module for ip_vti.

Message ID 20120629013017.GA4649@debian-saurabh-64.vyatta.com
State Changes Requested, archived
Delegated to: David Miller
Headers show

Commit Message

Saurabh June 29, 2012, 1:30 a.m. UTC
New VTI tunnel kernel module, Kconfig and Makefile changes.

Signed-off-by: Saurabh Mohan <saurabh.mohan@vyatta.com>
Reviewed-by: Stephen Hemminger <shemminger@vyatta.com>

---
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Comments

David Miller July 9, 2012, 6:47 a.m. UTC | #1
From: Saurabh <saurabh.mohan@vyatta.com>
Date: Thu, 28 Jun 2012 18:30:17 -0700

> +#define HASH_SIZE  16
> +#define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)

Define HASH such that it masks with (HASH_SIZE - 1) instead of
0xf, so that if HASH_SIZE is changed everything automatically
still works without having to remember to update the value in
HASH()'s definition too.

> +	if (skb->protocol != htons(ETH_P_IP))
> +		goto tx_error;

We are really past the point where we can add major inet protocol
features without supporting ipv6 as well.

> +	if (IS_ERR(rt)) {
> +		dev->stats.tx_carrier_errors++;
> +		goto tx_error_icmp;
> +	}
> +#ifdef CONFIG_XFRM
> +		/* if there is no transform then this tunnel is not functional.
> +		 * Or if the xfrm is not mode tunnel.
> +		 */
> +		if (!rt->dst.xfrm ||
> +		    rt->dst.xfrm->props.mode != XFRM_MODE_TUNNEL) {
> +			stats->tx_carrier_errors++;
> +			goto tx_error_icmp;
> +		}
> +#endif

This code in the CONFIG_XFRM block is not indented properly.

And this is a pointless CONFIG_* check, you can't even register
this tunnel outside of the XFRM code.  In fact the code already
depends upon INET_XFRM_MODE_TUNNEL which therefore automatically
means that CONFIG_XFRM must be set for this code.

> +	}
> +
> +
> +	if (tunnel->err_count > 0) {

Get rid of these extra blank lines.

> +	}
> +
> +
> +	IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |

Again.

The reason there are long periods of time between my attempts to
review your code (and probably the reason I'm the only person still
reviewing your work at all) is that I know there are going to be so
many problems to let you know about.  It's really painful to review
your work and I've spent so much time on the coding style and the
simpler issues that I really haven't considered the high level issues
of what your code is trying to do.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/include/linux/if_tunnel.h b/include/linux/if_tunnel.h
index 16b92d0..5efff60 100644
--- a/include/linux/if_tunnel.h
+++ b/include/linux/if_tunnel.h
@@ -80,4 +80,18 @@  enum {
 
 #define IFLA_GRE_MAX	(__IFLA_GRE_MAX - 1)
 
+/* VTI-mode i_flags */
+#define VTI_ISVTI 0x0001
+
+enum {
+	IFLA_VTI_UNSPEC,
+	IFLA_VTI_LINK,
+	IFLA_VTI_IKEY,
+	IFLA_VTI_OKEY,
+	IFLA_VTI_LOCAL,
+	IFLA_VTI_REMOTE,
+	__IFLA_VTI_MAX,
+};
+
+#define IFLA_VTI_MAX	(__IFLA_VTI_MAX - 1)
 #endif /* _IF_TUNNEL_H_ */
diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig
index 20f1cb5..32d467b 100644
--- a/net/ipv4/Kconfig
+++ b/net/ipv4/Kconfig
@@ -310,6 +310,16 @@  config SYN_COOKIES
 
 	  If unsure, say N.
 
+config NET_IPVTI
+	tristate "Virtual (secure) IP: tunneling"
+	select INET_TUNNEL
+	depends on INET_XFRM_MODE_TUNNEL
+	---help---
+	Tunneling means encapsulating data of one protocol type within
+	another protocol and sending it over a channel that understands the
+	Pencapsulating protocol. This can be used with xfrm mode tunnel to give
+	the notion of a secure tunnel for IPSEC and then use routing protocol on top.
+
 config INET_AH
 	tristate "IP: AH transformation"
 	select XFRM_ALGO
diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile
index ff75d3b..3999ce9 100644
--- a/net/ipv4/Makefile
+++ b/net/ipv4/Makefile
@@ -20,6 +20,7 @@  obj-$(CONFIG_IP_MROUTE) += ipmr.o
 obj-$(CONFIG_NET_IPIP) += ipip.o
 obj-$(CONFIG_NET_IPGRE_DEMUX) += gre.o
 obj-$(CONFIG_NET_IPGRE) += ip_gre.o
+obj-$(CONFIG_NET_IPVTI) += ip_vti.o
 obj-$(CONFIG_SYN_COOKIES) += syncookies.o
 obj-$(CONFIG_INET_AH) += ah4.o
 obj-$(CONFIG_INET_ESP) += esp4.o
diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c
new file mode 100644
index 0000000..910250d
--- /dev/null
+++ b/net/ipv4/ip_vti.c
@@ -0,0 +1,975 @@ 
+/*
+ *	Linux NET3: IP/IP protocol decoder modified to support virtual tunnel interface
+ *
+ *	Authors:
+ *		Saurabh Mohan (saurabh.mohan@vyatta.com) 05/07/2012
+ *
+ *	This program is free software; you can redistribute it and/or
+ *	modify it under the terms of the GNU General Public License
+ *	as published by the Free Software Foundation; either version
+ *	2 of the License, or (at your option) any later version.
+ *
+ */
+
+/*
+   This version of net/ipv4/ip_vti.c is cloned of net/ipv4/ipip.c
+
+   For comments look at net/ipv4/ip_gre.c --ANK
+ */
+
+
+#include <linux/capability.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/uaccess.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/in.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#include <linux/if_arp.h>
+#include <linux/mroute.h>
+#include <linux/init.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/if_ether.h>
+
+#include <net/sock.h>
+#include <net/ip.h>
+#include <net/icmp.h>
+#include <net/ipip.h>
+#include <net/inet_ecn.h>
+#include <net/xfrm.h>
+#include <net/net_namespace.h>
+#include <net/netns/generic.h>
+
+#define HASH_SIZE  16
+#define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
+
+static struct rtnl_link_ops vti_link_ops __read_mostly;
+
+static int vti_net_id __read_mostly;
+struct vti_net {
+	struct ip_tunnel __rcu *tunnels_r_l[HASH_SIZE];
+	struct ip_tunnel __rcu *tunnels_r[HASH_SIZE];
+	struct ip_tunnel __rcu *tunnels_l[HASH_SIZE];
+	struct ip_tunnel __rcu *tunnels_wc[1];
+	struct ip_tunnel **tunnels[4];
+
+	struct net_device *fb_tunnel_dev;
+};
+
+static int vti_fb_tunnel_init(struct net_device *dev);
+static int vti_tunnel_init(struct net_device *dev);
+static void vti_tunnel_setup(struct net_device *dev);
+static void vti_dev_free(struct net_device *dev);
+static int vti_tunnel_bind_dev(struct net_device *dev);
+
+/*
+ * Locking : hash tables are protected by RCU and RTNL
+ */
+
+#define for_each_ip_tunnel_rcu(start) \
+	for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
+
+/* often modified stats are per cpu, other are shared (netdev->stats) */
+struct pcpu_tstats {
+	u64	rx_packets;
+	u64	rx_bytes;
+	u64	tx_packets;
+	u64	tx_bytes;
+	struct	u64_stats_sync	syncp;
+};
+
+#define VTI_XMIT(stats1, stats2) do {				\
+	int err;						\
+	int pkt_len = skb->len;					\
+	err = dst_output(skb);					\
+	if (net_xmit_eval(err) == 0) {				\
+		(stats1)->tx_bytes += pkt_len;			\
+		(stats1)->tx_packets++;				\
+	} else {						\
+		(stats2)->tx_errors++;				\
+		(stats2)->tx_aborted_errors++;			\
+	}							\
+} while (0)
+
+
+static struct rtnl_link_stats64 *vti_get_stats64(struct net_device *dev,
+						 struct rtnl_link_stats64 *tot)
+{
+	int i;
+
+	for_each_possible_cpu(i) {
+		const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i);
+		u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
+		unsigned int start;
+
+		do {
+			start = u64_stats_fetch_begin_bh(&tstats->syncp);
+			rx_packets = tstats->rx_packets;
+			tx_packets = tstats->tx_packets;
+			rx_bytes = tstats->rx_bytes;
+			tx_bytes = tstats->tx_bytes;
+		} while (u64_stats_fetch_retry_bh(&tstats->syncp, start));
+
+		tot->rx_packets += rx_packets;
+		tot->tx_packets += tx_packets;
+		tot->rx_bytes   += rx_bytes;
+		tot->tx_bytes   += tx_bytes;
+	}
+
+	tot->multicast = dev->stats.multicast;
+	tot->rx_crc_errors = dev->stats.rx_crc_errors;
+	tot->rx_fifo_errors = dev->stats.rx_fifo_errors;
+	tot->rx_length_errors = dev->stats.rx_length_errors;
+	tot->rx_errors = dev->stats.rx_errors;
+	tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
+	tot->tx_carrier_errors = dev->stats.tx_carrier_errors;
+	tot->tx_dropped = dev->stats.tx_dropped;
+	tot->tx_aborted_errors = dev->stats.tx_aborted_errors;
+	tot->tx_errors = dev->stats.tx_errors;
+
+	return tot;
+}
+
+static struct ip_tunnel *vti_tunnel_lookup(struct net *net,
+					   __be32 remote, __be32 local)
+{
+	unsigned h0 = HASH(remote);
+	unsigned h1 = HASH(local);
+	struct ip_tunnel *t;
+	struct vti_net *ipn = net_generic(net, vti_net_id);
+
+	for_each_ip_tunnel_rcu(ipn->tunnels_r_l[h0 ^ h1])
+		if (local == t->parms.iph.saddr &&
+		    remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
+			return t;
+	for_each_ip_tunnel_rcu(ipn->tunnels_r[h0])
+		if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
+			return t;
+
+	for_each_ip_tunnel_rcu(ipn->tunnels_l[h1])
+		if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP))
+			return t;
+
+	for_each_ip_tunnel_rcu(ipn->tunnels_wc[0])
+		if (t && (t->dev->flags&IFF_UP))
+			return t;
+	return NULL;
+}
+
+static struct ip_tunnel **__vti_bucket(struct vti_net *ipn,
+				       struct ip_tunnel_parm *parms)
+{
+	__be32 remote = parms->iph.daddr;
+	__be32 local = parms->iph.saddr;
+	unsigned h = 0;
+	int prio = 0;
+
+	if (remote) {
+		prio |= 2;
+		h ^= HASH(remote);
+	}
+	if (local) {
+		prio |= 1;
+		h ^= HASH(local);
+	}
+	return &ipn->tunnels[prio][h];
+}
+
+static inline struct ip_tunnel **vti_bucket(struct vti_net *ipn,
+					    struct ip_tunnel *t)
+{
+	return __vti_bucket(ipn, &t->parms);
+}
+
+static void vti_tunnel_unlink(struct vti_net *ipn, struct ip_tunnel *t)
+{
+	struct ip_tunnel __rcu **tp;
+	struct ip_tunnel *iter;
+
+	for (tp = vti_bucket(ipn, t);
+	     (iter = rtnl_dereference(*tp)) != NULL;
+	     tp = &iter->next) {
+		if (t == iter) {
+			rcu_assign_pointer(*tp, t->next);
+			break;
+		}
+	}
+}
+
+static void vti_tunnel_link(struct vti_net *ipn, struct ip_tunnel *t)
+{
+	struct ip_tunnel __rcu **tp = vti_bucket(ipn, t);
+
+	rcu_assign_pointer(t->next, rtnl_dereference(*tp));
+	rcu_assign_pointer(*tp, t);
+}
+
+static struct ip_tunnel *vti_tunnel_locate(struct net *net,
+					   struct ip_tunnel_parm *parms,
+					   int create)
+{
+	__be32 remote = parms->iph.daddr;
+	__be32 local = parms->iph.saddr;
+	struct ip_tunnel *t, *nt;
+	struct ip_tunnel __rcu **tp;
+	struct net_device *dev;
+	char name[IFNAMSIZ];
+	struct vti_net *ipn = net_generic(net, vti_net_id);
+
+	for (tp = __vti_bucket(ipn, parms);
+	     (t = rtnl_dereference(*tp)) != NULL;
+	     tp = &t->next) {
+		if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr)
+			return t;
+	}
+	if (!create)
+		return NULL;
+
+	if (parms->name[0])
+		strlcpy(name, parms->name, IFNAMSIZ);
+	else
+		strcpy(name, "vti%d");
+
+	dev = alloc_netdev(sizeof(*t), name, vti_tunnel_setup);
+	if (dev == NULL)
+		return NULL;
+
+	dev_net_set(dev, net);
+
+	nt = netdev_priv(dev);
+	nt->parms = *parms;
+	dev->rtnl_link_ops = &vti_link_ops;
+
+	vti_tunnel_bind_dev(dev);
+
+	if (register_netdevice(dev) < 0)
+		goto failed_free;
+
+	dev_hold(dev);
+	vti_tunnel_link(ipn, nt);
+	return nt;
+
+ failed_free:
+	free_netdev(dev);
+	return NULL;
+}
+
+static void vti_tunnel_uninit(struct net_device *dev)
+{
+	struct net *net = dev_net(dev);
+	struct vti_net *ipn = net_generic(net, vti_net_id);
+
+	if (dev == ipn->fb_tunnel_dev)
+		RCU_INIT_POINTER(ipn->tunnels_wc[0], NULL);
+	else
+		vti_tunnel_unlink(ipn, netdev_priv(dev));
+	dev_put(dev);
+}
+
+static int vti_err(struct sk_buff *skb, u32 info)
+{
+
+	/* All the routers (except for Linux) return only
+	 * 8 bytes of packet payload. It means, that precise relaying of
+	 * ICMP in the real Internet is absolutely infeasible.
+	 */
+	struct iphdr *iph = (struct iphdr *)skb->data;
+	const int type = icmp_hdr(skb)->type;
+	const int code = icmp_hdr(skb)->code;
+	struct ip_tunnel *t;
+	int err;
+
+	switch (type) {
+	default:
+	case ICMP_PARAMETERPROB:
+		return 0;
+
+	case ICMP_DEST_UNREACH:
+		switch (code) {
+		case ICMP_SR_FAILED:
+		case ICMP_PORT_UNREACH:
+			/* Impossible event. */
+			return 0;
+		default:
+			/* All others are translated to HOST_UNREACH. */
+			break;
+		}
+		break;
+	case ICMP_TIME_EXCEEDED:
+		if (code != ICMP_EXC_TTL)
+			return 0;
+		break;
+	}
+
+	err = -ENOENT;
+
+	rcu_read_lock();
+	t = vti_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr);
+	if (t == NULL)
+		goto out;
+
+	if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
+		ipv4_update_pmtu(skb, dev_net(skb->dev), info,
+				 t->parms.link, 0, IPPROTO_IPIP, 0);
+		err = 0;
+		goto out;
+	}
+
+	err = 0;
+	if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
+		goto out;
+
+	if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
+		t->err_count++;
+	else
+		t->err_count = 1;
+	t->err_time = jiffies;
+out:
+	rcu_read_unlock();
+	return err;
+}
+
+/*
+ * We dont digest the packet therefore let the packet pass.
+ */
+static int vti_rcv(struct sk_buff *skb)
+{
+	struct ip_tunnel *tunnel;
+	const struct iphdr *iph = ip_hdr(skb);
+
+	rcu_read_lock();
+	tunnel = vti_tunnel_lookup(dev_net(skb->dev), iph->saddr, iph->daddr);
+	if (tunnel != NULL) {
+		struct pcpu_tstats *tstats;
+
+		tstats = this_cpu_ptr(tunnel->dev->tstats);
+		tstats->rx_packets++;
+		tstats->rx_bytes += skb->len;
+
+		skb->dev = tunnel->dev;
+		rcu_read_unlock();
+		/* We do not eat the packet here therefore return 1 */
+		return 1;
+	}
+	rcu_read_unlock();
+
+	return -1;
+}
+
+/*
+ *	This function assumes it is being called from dev_queue_xmit()
+ *	and that skb is filled properly by that function.
+ */
+
+static netdev_tx_t vti_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct ip_tunnel *tunnel = netdev_priv(dev);
+	struct pcpu_tstats *tstats;
+	struct net_device_stats *stats = &tunnel->dev->stats;
+	struct iphdr  *tiph = &tunnel->parms.iph;
+	u8     tos = tunnel->parms.iph.tos;
+	struct rtable *rt;		/* Route to the other host */
+	struct net_device *tdev;	/* Device to other host */
+	struct iphdr  *old_iph = ip_hdr(skb);
+	__be32 dst = tiph->daddr;
+	struct flowi4 fl4;
+
+	if (skb->protocol != htons(ETH_P_IP))
+		goto tx_error;
+
+	if (tos&1)
+		tos = old_iph->tos;
+
+	if (!dst) {
+		/* NBMA tunnel */
+		rt = skb_rtable(skb);
+		if (rt == NULL) {
+			stats->tx_fifo_errors++;
+			goto tx_error;
+		}
+		dst = rt->rt_gateway;
+		if (dst == 0)
+			goto tx_error_icmp;
+	}
+
+	memset(&fl4, 0, sizeof(fl4));
+	flowi4_init_output(&fl4, tunnel->parms.link,
+			   htonl(tunnel->parms.i_key), RT_TOS(tos), RT_SCOPE_UNIVERSE,
+			   IPPROTO_IPIP, 0,
+			   dst, tiph->saddr, 0, 0);
+	rt = ip_route_output_key(dev_net(dev), &fl4);
+	if (IS_ERR(rt)) {
+		dev->stats.tx_carrier_errors++;
+		goto tx_error_icmp;
+	}
+#ifdef CONFIG_XFRM
+		/* if there is no transform then this tunnel is not functional.
+		 * Or if the xfrm is not mode tunnel.
+		 */
+		if (!rt->dst.xfrm ||
+		    rt->dst.xfrm->props.mode != XFRM_MODE_TUNNEL) {
+			stats->tx_carrier_errors++;
+			goto tx_error_icmp;
+		}
+#endif
+	tdev = rt->dst.dev;
+
+	if (tdev == dev) {
+		ip_rt_put(rt);
+		stats->collisions++;
+		goto tx_error;
+
+	}
+
+
+	if (tunnel->err_count > 0) {
+		if (time_before(jiffies,
+				tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
+			tunnel->err_count--;
+			dst_link_failure(skb);
+		} else
+			tunnel->err_count = 0;
+	}
+
+
+	IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |
+			      IPSKB_REROUTED);
+	skb_dst_drop(skb);
+	skb_dst_set(skb, &rt->dst);
+	nf_reset(skb);
+	skb->dev = skb_dst(skb)->dev;
+
+	tstats = this_cpu_ptr(dev->tstats);
+	VTI_XMIT(tstats, &dev->stats);
+	return NETDEV_TX_OK;
+
+tx_error_icmp:
+	dst_link_failure(skb);
+tx_error:
+	stats->tx_errors++;
+	dev_kfree_skb(skb);
+	return NETDEV_TX_OK;
+}
+
+static int vti_tunnel_bind_dev(struct net_device *dev)
+{
+	struct net_device *tdev = NULL;
+	struct ip_tunnel *tunnel;
+	struct iphdr *iph;
+
+	tunnel = netdev_priv(dev);
+	iph = &tunnel->parms.iph;
+
+	if (iph->daddr) {
+		struct rtable *rt;
+		struct flowi4 fl4;
+		memset(&fl4, 0, sizeof(fl4));
+		flowi4_init_output(&fl4, tunnel->parms.link,
+				   htonl(tunnel->parms.i_key), RT_TOS(iph->tos), RT_SCOPE_UNIVERSE,
+				   IPPROTO_IPIP, 0,
+				   iph->daddr, iph->saddr, 0, 0);
+		rt = ip_route_output_key(dev_net(dev), &fl4);
+		if (!IS_ERR(rt)) {
+			tdev = rt->dst.dev;
+			ip_rt_put(rt);
+		}
+		dev->flags |= IFF_POINTOPOINT;
+	}
+
+	if (!tdev && tunnel->parms.link)
+		tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
+
+	if (tdev) {
+		dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
+		dev->mtu = tdev->mtu;
+	}
+	dev->iflink = tunnel->parms.link;
+	return dev->mtu;
+}
+
+static int
+vti_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+	int err = 0;
+	struct ip_tunnel_parm p;
+	struct ip_tunnel *t;
+	struct net *net = dev_net(dev);
+	struct vti_net *ipn = net_generic(net, vti_net_id);
+
+	switch (cmd) {
+	case SIOCGETTUNNEL:
+		t = NULL;
+		if (dev == ipn->fb_tunnel_dev) {
+			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
+				err = -EFAULT;
+				break;
+			}
+			t = vti_tunnel_locate(net, &p, 0);
+		}
+		if (t == NULL)
+			t = netdev_priv(dev);
+		memcpy(&p, &t->parms, sizeof(p));
+		p.i_flags |= GRE_KEY;
+		p.o_flags |= GRE_KEY;
+		if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
+			err = -EFAULT;
+		break;
+
+	case SIOCADDTUNNEL:
+	case SIOCCHGTUNNEL:
+		err = -EPERM;
+		if (!capable(CAP_NET_ADMIN))
+			goto done;
+
+		err = -EFAULT;
+		if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
+			goto done;
+
+		err = -EINVAL;
+		if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP ||
+		    p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
+			goto done;
+		if (p.iph.ttl)
+			p.iph.frag_off |= htons(IP_DF);
+
+		t = vti_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
+
+		if (dev != ipn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
+			if (t != NULL) {
+				if (t->dev != dev) {
+					err = -EEXIST;
+					break;
+				}
+			} else {
+				if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
+				    (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
+					err = -EINVAL;
+					break;
+				}
+				t = netdev_priv(dev);
+				vti_tunnel_unlink(ipn, t);
+				synchronize_net();
+				t->parms.iph.saddr = p.iph.saddr;
+				t->parms.iph.daddr = p.iph.daddr;
+				t->parms.i_key = p.i_key;
+				t->parms.o_key = p.o_key;
+				t->parms.iph.protocol = IPPROTO_IPIP;
+				memcpy(dev->dev_addr, &p.iph.saddr, 4);
+				memcpy(dev->broadcast, &p.iph.daddr, 4);
+				vti_tunnel_link(ipn, t);
+				netdev_state_change(dev);
+			}
+		}
+
+		if (t) {
+			err = 0;
+			if (cmd == SIOCCHGTUNNEL) {
+				t->parms.iph.ttl = p.iph.ttl;
+				t->parms.iph.tos = p.iph.tos;
+				t->parms.iph.frag_off = p.iph.frag_off;
+				t->parms.i_key = p.i_key;
+				t->parms.o_key = p.o_key;
+				if (t->parms.link != p.link) {
+					t->parms.link = p.link;
+					vti_tunnel_bind_dev(dev);
+					netdev_state_change(dev);
+				}
+			}
+			if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
+				err = -EFAULT;
+		} else
+			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
+		break;
+
+	case SIOCDELTUNNEL:
+		err = -EPERM;
+		if (!capable(CAP_NET_ADMIN))
+			goto done;
+
+		if (dev == ipn->fb_tunnel_dev) {
+			err = -EFAULT;
+			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
+				goto done;
+			err = -ENOENT;
+
+			t = vti_tunnel_locate(net, &p, 0);
+			if (t == NULL)
+				goto done;
+			err = -EPERM;
+			if (t->dev == ipn->fb_tunnel_dev)
+				goto done;
+			dev = t->dev;
+		}
+		unregister_netdevice(dev);
+		err = 0;
+		break;
+
+	default:
+		err = -EINVAL;
+	}
+
+done:
+	return err;
+}
+
+static int vti_tunnel_change_mtu(struct net_device *dev, int new_mtu)
+{
+	if (new_mtu < 68 || new_mtu > 0xFFF8)
+		return -EINVAL;
+	dev->mtu = new_mtu;
+	return 0;
+}
+
+static const struct net_device_ops vti_netdev_ops = {
+	.ndo_init	= vti_tunnel_init,
+	.ndo_uninit	= vti_tunnel_uninit,
+	.ndo_start_xmit	= vti_tunnel_xmit,
+	.ndo_do_ioctl	= vti_tunnel_ioctl,
+	.ndo_change_mtu	= vti_tunnel_change_mtu,
+	.ndo_get_stats64  = vti_get_stats64,
+};
+
+static void vti_dev_free(struct net_device *dev)
+{
+	free_percpu(dev->tstats);
+	free_netdev(dev);
+}
+
+static void vti_tunnel_setup(struct net_device *dev)
+{
+	dev->netdev_ops		= &vti_netdev_ops;
+	dev->destructor		= vti_dev_free;
+
+	dev->type		= ARPHRD_TUNNEL;
+	dev->hard_header_len	= LL_MAX_HEADER + sizeof(struct iphdr);
+	dev->mtu		= ETH_DATA_LEN;
+	dev->flags		= IFF_NOARP;
+	dev->iflink		= 0;
+	dev->addr_len		= 4;
+	dev->features		|= NETIF_F_NETNS_LOCAL;
+	dev->features		|= NETIF_F_LLTX;
+	dev->priv_flags		&= ~IFF_XMIT_DST_RELEASE;
+}
+
+static int vti_tunnel_init(struct net_device *dev)
+{
+	struct ip_tunnel *tunnel = netdev_priv(dev);
+
+	tunnel->dev = dev;
+	strcpy(tunnel->parms.name, dev->name);
+
+	memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
+	memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
+
+	dev->tstats = alloc_percpu(struct pcpu_tstats);
+	if (!dev->tstats)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static int __net_init vti_fb_tunnel_init(struct net_device *dev)
+{
+	struct ip_tunnel *tunnel = netdev_priv(dev);
+	struct iphdr *iph = &tunnel->parms.iph;
+	struct vti_net *ipn = net_generic(dev_net(dev), vti_net_id);
+
+	tunnel->dev = dev;
+	strcpy(tunnel->parms.name, dev->name);
+
+	iph->version		= 4;
+	iph->protocol		= IPPROTO_IPIP;
+	iph->ihl		= 5;
+
+	dev->tstats = alloc_percpu(struct pcpu_tstats);
+	if (!dev->tstats)
+		return -ENOMEM;
+
+	dev_hold(dev);
+	rcu_assign_pointer(ipn->tunnels_wc[0], tunnel);
+	return 0;
+}
+
+static struct xfrm_tunnel vti_handler __read_mostly = {
+	.handler	=	vti_rcv,
+	.err_handler	=	vti_err,
+	.priority	=	1,
+};
+
+static void vti_destroy_tunnels(struct vti_net *ipn, struct list_head *head)
+{
+	int prio;
+
+	for (prio = 1; prio < 4; prio++) {
+		int h;
+		for (h = 0; h < HASH_SIZE; h++) {
+			struct ip_tunnel *t;
+
+			t = rtnl_dereference(ipn->tunnels[prio][h]);
+			while (t != NULL) {
+				unregister_netdevice_queue(t->dev, head);
+				t = rtnl_dereference(t->next);
+			}
+		}
+	}
+}
+
+static int __net_init vti_init_net(struct net *net)
+{
+	int err;
+	struct vti_net *ipn = net_generic(net, vti_net_id);
+
+	ipn->tunnels[0] = ipn->tunnels_wc;
+	ipn->tunnels[1] = ipn->tunnels_l;
+	ipn->tunnels[2] = ipn->tunnels_r;
+	ipn->tunnels[3] = ipn->tunnels_r_l;
+
+	ipn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel),
+					   "ip_vti0",
+					   vti_tunnel_setup);
+	if (!ipn->fb_tunnel_dev) {
+		err = -ENOMEM;
+		goto err_alloc_dev;
+	}
+	dev_net_set(ipn->fb_tunnel_dev, net);
+
+	err = vti_fb_tunnel_init(ipn->fb_tunnel_dev);
+	if (err)
+		goto err_reg_dev;
+	ipn->fb_tunnel_dev->rtnl_link_ops = &vti_link_ops;
+
+	err = register_netdev(ipn->fb_tunnel_dev);
+	if (err)
+		goto err_reg_dev;
+	return 0;
+
+err_reg_dev:
+	vti_dev_free(ipn->fb_tunnel_dev);
+err_alloc_dev:
+	/* nothing */
+	return err;
+}
+
+static void __net_exit vti_exit_net(struct net *net)
+{
+	struct vti_net *ipn = net_generic(net, vti_net_id);
+	LIST_HEAD(list);
+
+	rtnl_lock();
+	vti_destroy_tunnels(ipn, &list);
+	unregister_netdevice_many(&list);
+	rtnl_unlock();
+}
+
+static struct pernet_operations vti_net_ops = {
+	.init = vti_init_net,
+	.exit = vti_exit_net,
+	.id   = &vti_net_id,
+	.size = sizeof(struct vti_net),
+};
+
+static int vti_tunnel_validate(struct nlattr *tb[], struct nlattr *data[])
+{
+	return 0;
+}
+
+static void vti_netlink_parms(struct nlattr *data[],
+			      struct ip_tunnel_parm *parms)
+{
+	memset(parms, 0, sizeof(*parms));
+
+	parms->iph.protocol = IPPROTO_IPIP;
+
+	if (!data)
+		return;
+
+	if (data[IFLA_VTI_LINK])
+		parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
+
+	if (data[IFLA_VTI_IKEY])
+		parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
+
+	if (data[IFLA_VTI_OKEY])
+		parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
+
+	if (data[IFLA_VTI_LOCAL])
+		parms->iph.saddr = nla_get_be32(data[IFLA_VTI_LOCAL]);
+
+	if (data[IFLA_VTI_REMOTE])
+		parms->iph.daddr = nla_get_be32(data[IFLA_VTI_REMOTE]);
+
+}
+
+static int vti_newlink(struct net *src_net, struct net_device *dev, struct nlattr *tb[],
+		       struct nlattr *data[])
+{
+	struct ip_tunnel *nt;
+	struct net *net = dev_net(dev);
+	struct vti_net *ipn = net_generic(net, vti_net_id);
+	int mtu;
+	int err;
+
+	nt = netdev_priv(dev);
+	vti_netlink_parms(data, &nt->parms);
+
+	if (vti_tunnel_locate(net, &nt->parms, 0))
+		return -EEXIST;
+
+	mtu = vti_tunnel_bind_dev(dev);
+	if (!tb[IFLA_MTU])
+		dev->mtu = mtu;
+
+	err = register_netdevice(dev);
+	if (err)
+		goto out;
+
+	dev_hold(dev);
+	vti_tunnel_link(ipn, nt);
+
+out:
+	return err;
+	return 0;
+}
+
+static int vti_changelink(struct net_device *dev, struct nlattr *tb[],
+			  struct nlattr *data[])
+{
+	struct ip_tunnel *t, *nt;
+	struct net *net = dev_net(dev);
+	struct vti_net *ipn = net_generic(net, vti_net_id);
+	struct ip_tunnel_parm p;
+	int mtu;
+
+	if (dev == ipn->fb_tunnel_dev)
+		return -EINVAL;
+
+	nt = netdev_priv(dev);
+	vti_netlink_parms(data, &p);
+
+	t = vti_tunnel_locate(net, &p, 0);
+
+	if (t) {
+		if (t->dev != dev)
+			return -EEXIST;
+	} else {
+		t = nt;
+
+		vti_tunnel_unlink(ipn, t);
+		t->parms.iph.saddr = p.iph.saddr;
+		t->parms.iph.daddr = p.iph.daddr;
+		t->parms.i_key = p.i_key;
+		t->parms.o_key = p.o_key;
+		if (dev->type != ARPHRD_ETHER) {
+			memcpy(dev->dev_addr, &p.iph.saddr, 4);
+			memcpy(dev->broadcast, &p.iph.daddr, 4);
+		}
+		vti_tunnel_link(ipn, t);
+		netdev_state_change(dev);
+	}
+
+	if (t->parms.link != p.link) {
+		t->parms.link = p.link;
+		mtu = vti_tunnel_bind_dev(dev);
+		if (!tb[IFLA_MTU])
+			dev->mtu = mtu;
+		netdev_state_change(dev);
+	}
+
+	return 0;
+}
+
+static size_t vti_get_size(const struct net_device *dev)
+{
+	return
+		/* IFLA_VTI_LINK */
+		nla_total_size(4) +
+		/* IFLA_VTI_IKEY */
+		nla_total_size(4) +
+		/* IFLA_VTI_OKEY */
+		nla_total_size(4) +
+		/* IFLA_VTI_LOCAL */
+		nla_total_size(4) +
+		/* IFLA_VTI_REMOTE */
+		nla_total_size(4) +
+		0;
+}
+
+static int vti_fill_info(struct sk_buff *skb, const struct net_device *dev)
+{
+	struct ip_tunnel *t = netdev_priv(dev);
+	struct ip_tunnel_parm *p = &t->parms;
+
+	nla_put_u32(skb, IFLA_VTI_LINK, p->link);
+	nla_put_be32(skb, IFLA_VTI_IKEY, p->i_key);
+	nla_put_be32(skb, IFLA_VTI_OKEY, p->o_key);
+	nla_put_be32(skb, IFLA_VTI_LOCAL, p->iph.saddr);
+	nla_put_be32(skb, IFLA_VTI_REMOTE, p->iph.daddr);
+
+	return 0;
+}
+
+static const struct nla_policy vti_policy[IFLA_VTI_MAX + 1] = {
+	[IFLA_VTI_LINK]		= { .type = NLA_U32 },
+	[IFLA_VTI_IKEY]		= { .type = NLA_U32 },
+	[IFLA_VTI_OKEY]		= { .type = NLA_U32 },
+	[IFLA_VTI_LOCAL]	= { .len = FIELD_SIZEOF(struct iphdr, saddr) },
+	[IFLA_VTI_REMOTE]	= { .len = FIELD_SIZEOF(struct iphdr, daddr) },
+};
+
+static struct rtnl_link_ops vti_link_ops __read_mostly = {
+	.kind		= "vti",
+	.maxtype	= IFLA_VTI_MAX,
+	.policy		= vti_policy,
+	.priv_size	= sizeof(struct ip_tunnel),
+	.setup		= vti_tunnel_setup,
+	.validate	= vti_tunnel_validate,
+	.newlink	= vti_newlink,
+	.changelink	= vti_changelink,
+	.get_size	= vti_get_size,
+	.fill_info	= vti_fill_info,
+};
+
+static int __init vti_init(void)
+{
+	int err;
+
+	pr_info("IPv4 over IPSec tunneling driver\n");
+
+	err = register_pernet_device(&vti_net_ops);
+	if (err < 0)
+		return err;
+	err = xfrm4_mode_tunnel_input_register(&vti_handler);
+	if (err < 0) {
+		unregister_pernet_device(&vti_net_ops);
+		pr_info(KERN_INFO "vti init: can't register tunnel\n");
+	}
+
+	err = rtnl_link_register(&vti_link_ops);
+	if (err < 0)
+		goto rtnl_link_failed;
+
+	return err;
+
+rtnl_link_failed:
+	xfrm4_mode_tunnel_input_deregister(&vti_handler);
+	unregister_pernet_device(&vti_net_ops);
+	return err;
+}
+
+static void __exit vti_fini(void)
+{
+	rtnl_link_unregister(&vti_link_ops);
+	if (xfrm4_mode_tunnel_input_deregister(&vti_handler))
+		pr_info("vti close: can't deregister tunnel\n");
+
+	unregister_pernet_device(&vti_net_ops);
+}
+
+module_init(vti_init);
+module_exit(vti_fini);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_RTNL_LINK("vti");
+MODULE_ALIAS_NETDEV("ip_vti0");