Patchwork [RESEND,net-next] GRE over IPv6

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Submitter xeb@mail.ru
Date Aug. 10, 2012, 7:08 a.m.
Message ID <2771535.Z5nRARPP6B@dima>
Download mbox | patch
Permalink /patch/176391/
State Rejected
Delegated to: David Miller
Headers show

Comments

xeb@mail.ru - Aug. 10, 2012, 7:08 a.m.
GRE over IPv6 implementation.

Signed-off-by: Dmitry Kozlov <xeb@mail.ru>
---
 include/linux/if_arp.h     |    1 +
 include/linux/if_tunnel.h  |    3 +
 include/linux/ip6_tunnel.h |   17 +
 include/net/ip6_tunnel.h   |   41 +-
 include/net/ipv6.h         |    1 +
 net/ipv6/Kconfig           |   16 +
 net/ipv6/Makefile          |    1 +
 net/ipv6/ip6_gre.c         | 1791 
++++++++++++++++++++++++++++++++++++++++++++
 net/ipv6/ip6_tunnel.c      |   89 ++-
 9 files changed, 1934 insertions(+), 26 deletions(-)

 
@@ -139,20 +139,23 @@ static inline struct dst_entry *ip6_tnl_dst_check(struct 
ip6_tnl *t)
 
 	return dst;
 }
+EXPORT_SYMBOL_GPL(ip6_tnl_dst_check);
 
-static inline void ip6_tnl_dst_reset(struct ip6_tnl *t)
+void ip6_tnl_dst_reset(struct ip6_tnl *t)
 {
 	dst_release(t->dst_cache);
 	t->dst_cache = NULL;
 }
+EXPORT_SYMBOL_GPL(ip6_tnl_dst_reset);
 
-static inline void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry 
*dst)
+void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst)
 {
 	struct rt6_info *rt = (struct rt6_info *) dst;
 	t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
 	dst_release(t->dst_cache);
 	t->dst_cache = dst;
 }
+EXPORT_SYMBOL_GPL(ip6_tnl_dst_store);
 
 /**
  * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
@@ -200,7 +203,7 @@ ip6_tnl_lookup(struct net *net, const struct in6_addr 
*remote, const struct in6_
  **/
 
 static struct ip6_tnl __rcu **
-ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct ip6_tnl_parm *p)
+ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p)
 {
 	const struct in6_addr *remote = &p->raddr;
 	const struct in6_addr *local = &p->laddr;
@@ -267,7 +270,7 @@ static void ip6_dev_free(struct net_device *dev)
  *   created tunnel or NULL
  **/
 
-static struct ip6_tnl *ip6_tnl_create(struct net *net, struct ip6_tnl_parm 
*p)
+static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm 
*p)
 {
 	struct net_device *dev;
 	struct ip6_tnl *t;
@@ -322,7 +325,7 @@ failed:
  **/
 
 static struct ip6_tnl *ip6_tnl_locate(struct net *net,
-		struct ip6_tnl_parm *p, int create)
+		struct __ip6_tnl_parm *p, int create)
 {
 	const struct in6_addr *remote = &p->raddr;
 	const struct in6_addr *local = &p->laddr;
@@ -374,8 +377,7 @@ ip6_tnl_dev_uninit(struct net_device *dev)
  *   else index to encapsulation limit
  **/
 
-static __u16
-parse_tlv_tnl_enc_lim(struct sk_buff *skb, __u8 * raw)
+__u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw)
 {
 	const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) raw;
 	__u8 nexthdr = ipv6h->nexthdr;
@@ -425,6 +427,7 @@ parse_tlv_tnl_enc_lim(struct sk_buff *skb, __u8 * raw)
 	}
 	return 0;
 }
+EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim);
 
 /**
  * ip6_tnl_err - tunnel error handler
@@ -480,7 +483,7 @@ ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct 
inet6_skb_parm *opt,
 	case ICMPV6_PARAMPROB:
 		teli = 0;
 		if ((*code) == ICMPV6_HDR_FIELD)
-			teli = parse_tlv_tnl_enc_lim(skb, skb->data);
+			teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
 
 		if (teli && teli == *info - 2) {
 			tel = (struct ipv6_tlv_tnl_enc_lim *) &skb-
>data[teli];
@@ -693,11 +696,11 @@ static void ip6ip6_dscp_ecn_decapsulate(const struct 
ip6_tnl *t,
 		IP6_ECN_set_ce(ipv6_hdr(skb));
 }
 
-static __u32 ip6_tnl_get_cap(struct ip6_tnl *t,
+__u32 ip6_tnl_get_cap(struct ip6_tnl *t,
 			     const struct in6_addr *laddr,
 			     const struct in6_addr *raddr)
 {
-	struct ip6_tnl_parm *p = &t->parms;
+	struct __ip6_tnl_parm *p = &t->parms;
 	int ltype = ipv6_addr_type(laddr);
 	int rtype = ipv6_addr_type(raddr);
 	__u32 flags = 0;
@@ -715,13 +718,14 @@ static __u32 ip6_tnl_get_cap(struct ip6_tnl *t,
 	}
 	return flags;
 }
+EXPORT_SYMBOL(ip6_tnl_get_cap);
 
 /* called with rcu_read_lock() */
-static inline int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
+int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
 				  const struct in6_addr *laddr,
 				  const struct in6_addr *raddr)
 {
-	struct ip6_tnl_parm *p = &t->parms;
+	struct __ip6_tnl_parm *p = &t->parms;
 	int ret = 0;
 	struct net *net = dev_net(t->dev);
 
@@ -740,6 +744,7 @@ static inline int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
 	}
 	return ret;
 }
+EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl);
 
 /**
  * ip6_tnl_rcv - decapsulate IPv6 packet and retransmit it locally
@@ -859,9 +864,9 @@ ip6_tnl_addr_conflict(const struct ip6_tnl *t, const 
struct ipv6hdr *hdr)
 	return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 }
 
-static inline int ip6_tnl_xmit_ctl(struct ip6_tnl *t)
+int ip6_tnl_xmit_ctl(struct ip6_tnl *t)
 {
-	struct ip6_tnl_parm *p = &t->parms;
+	struct __ip6_tnl_parm *p = &t->parms;
 	int ret = 0;
 	struct net *net = dev_net(t->dev);
 
@@ -885,6 +890,8 @@ static inline int ip6_tnl_xmit_ctl(struct ip6_tnl *t)
 	}
 	return ret;
 }
+EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl);
+
 /**
  * ip6_tnl_xmit2 - encapsulate packet and send
  *   @skb: the outgoing socket buffer
@@ -1085,7 +1092,7 @@ ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device 
*dev)
 	    !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h))
 		return -1;
 
-	offset = parse_tlv_tnl_enc_lim(skb, skb_network_header(skb));
+	offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
 	if (offset > 0) {
 		struct ipv6_tlv_tnl_enc_lim *tel;
 		tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)
[offset];
@@ -1152,7 +1159,7 @@ tx_err:
 static void ip6_tnl_link_config(struct ip6_tnl *t)
 {
 	struct net_device *dev = t->dev;
-	struct ip6_tnl_parm *p = &t->parms;
+	struct __ip6_tnl_parm *p = &t->parms;
 	struct flowi6 *fl6 = &t->fl.u.ip6;
 
 	memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
@@ -1215,7 +1222,7 @@ static void ip6_tnl_link_config(struct ip6_tnl *t)
  **/
 
 static int
-ip6_tnl_change(struct ip6_tnl *t, struct ip6_tnl_parm *p)
+ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
 {
 	t->parms.laddr = p->laddr;
 	t->parms.raddr = p->raddr;
@@ -1230,6 +1237,34 @@ ip6_tnl_change(struct ip6_tnl *t, struct ip6_tnl_parm 
*p)
 	return 0;
 }
 
+static void
+ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm 
*u)
+{
+	p->laddr = u->laddr;
+	p->raddr = u->raddr;
+	p->flags = u->flags;
+	p->hop_limit = u->hop_limit;
+	p->encap_limit = u->encap_limit;
+	p->flowinfo = u->flowinfo;
+	p->link = u->link;
+	p->proto = u->proto;
+	memcpy(p->name, u->name, sizeof(u->name));
+}
+
+static void
+ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p)
+{
+	u->laddr = p->laddr;
+	u->raddr = p->raddr;
+	u->flags = p->flags;
+	u->hop_limit = p->hop_limit;
+	u->encap_limit = p->encap_limit;
+	u->flowinfo = p->flowinfo;
+	u->link = p->link;
+	u->proto = p->proto;
+	memcpy(u->name, p->name, sizeof(u->name));
+}
+
 /**
  * ip6_tnl_ioctl - configure ipv6 tunnels from userspace
  *   @dev: virtual device associated with tunnel
@@ -1263,6 +1298,7 @@ ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, 
int cmd)
 {
 	int err = 0;
 	struct ip6_tnl_parm p;
+	struct __ip6_tnl_parm p1;
 	struct ip6_tnl *t = NULL;
 	struct net *net = dev_net(dev);
 	struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
@@ -1274,11 +1310,12 @@ ip6_tnl_ioctl(struct net_device *dev, struct ifreq 
*ifr, int cmd)
 				err = -EFAULT;
 				break;
 			}
-			t = ip6_tnl_locate(net, &p, 0);
+			ip6_tnl_parm_from_user(&p1, &p);
+			t = ip6_tnl_locate(net, &p1, 0);
 		}
 		if (t == NULL)
 			t = netdev_priv(dev);
-		memcpy(&p, &t->parms, sizeof (p));
+		ip6_tnl_parm_to_user(&p, &t->parms);
 		if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) {
 			err = -EFAULT;
 		}
@@ -1295,7 +1332,8 @@ ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, 
int cmd)
 		if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
 		    p.proto != 0)
 			break;
-		t = ip6_tnl_locate(net, &p, cmd == SIOCADDTUNNEL);
+		ip6_tnl_parm_from_user(&p1, &p);
+		t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL);
 		if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
 			if (t != NULL) {
 				if (t->dev != dev) {
@@ -1307,13 +1345,14 @@ ip6_tnl_ioctl(struct net_device *dev, struct ifreq 
*ifr, int cmd)
 
 			ip6_tnl_unlink(ip6n, t);
 			synchronize_net();
-			err = ip6_tnl_change(t, &p);
+			err = ip6_tnl_change(t, &p1);
 			ip6_tnl_link(ip6n, t);
 			netdev_state_change(dev);
 		}
 		if (t) {
 			err = 0;
-			if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, 
sizeof (p)))
+			ip6_tnl_parm_to_user(&p, &t->parms);
+			if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, 
sizeof(p)))
 				err = -EFAULT;
 
 		} else
@@ -1329,7 +1368,9 @@ ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, 
int cmd)
 			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof 
(p)))
 				break;
 			err = -ENOENT;
-			if ((t = ip6_tnl_locate(net, &p, 0)) == NULL)
+			ip6_tnl_parm_from_user(&p1, &p);
+			t = ip6_tnl_locate(net, &p1, 0);
+			if (t == NULL)
 				break;
 			err = -EPERM;
 			if (t->dev == ip6n->fb_tnl_dev)
--
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David Miller - Aug. 10, 2012, 9:08 a.m.
From: Kozlov Dmitry <xeb@mail.ru>
Date: Fri, 10 Aug 2012 11:08:26 +0400

>  net/ipv6/ip6_gre.c         | 1791 
> ++++++++++++++++++++++++++++++++++++++++++++

Your mailer is still breaking up long lines, and in other ways
textually corrupting your patch.  Making it useless to us.

This problem is why even your last "RESEND" of this patch was
completely ignored, rejects, and not even looked at by anyone
for review.

And we will not look at this one either, sorry.  Please get your
act in gear.

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xeb@mail.ru - Aug. 10, 2012, 9:16 a.m.
But I resend patch as attachment, is it invalid too ?

On Friday 10 August 2012 02:08:32 David Miller wrote:
> From: Kozlov Dmitry <xeb@mail.ru>
> Date: Fri, 10 Aug 2012 11:08:26 +0400
> 
> >  net/ipv6/ip6_gre.c         | 1791
> > 
> > ++++++++++++++++++++++++++++++++++++++++++++
> 
> Your mailer is still breaking up long lines, and in other ways
> textually corrupting your patch.  Making it useless to us.
> 
> This problem is why even your last "RESEND" of this patch was
> completely ignored, rejects, and not even looked at by anyone
> for review.
> 
> And we will not look at this one either, sorry.  Please get your
> act in gear.

--
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David Miller - Aug. 10, 2012, 10:37 a.m.
From: Kozlov Dmitry <xeb@mail.ru>
Date: Fri, 10 Aug 2012 13:16 +0400

> But I resend patch as attachment, is it invalid too ?

It doesn't have the mail mangling errors, but it has another one:

+ git apply --check --whitespace=error-all RESEND-net-next-v2-GRE-over-IPv6.patch
RESEND-net-next-v2-GRE-over-IPv6.patch:1999: new blank line at EOF.
+
fatal: 1 line adds whitespace errors.
--
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Patch

diff --git a/include/linux/if_arp.h b/include/linux/if_arp.h
index f0e69c6..9adcc29 100644
--- a/include/linux/if_arp.h
+++ b/include/linux/if_arp.h
@@ -92,6 +92,7 @@ 
 #define ARPHRD_PHONET	820		/* PhoNet media type		*/
 #define ARPHRD_PHONET_PIPE 821		/* PhoNet pipe header		*/
 #define ARPHRD_CAIF	822		/* CAIF media type		*/
+#define ARPHRD_IP6GRE	823		/* GRE over IPv6		*/
 
 #define ARPHRD_VOID	  0xFFFF	/* Void type, nothing is known */
 #define ARPHRD_NONE	  0xFFFE	/* zero header length */
diff --git a/include/linux/if_tunnel.h b/include/linux/if_tunnel.h
index 5efff60..8c5035a 100644
--- a/include/linux/if_tunnel.h
+++ b/include/linux/if_tunnel.h
@@ -75,6 +75,9 @@  enum {
 	IFLA_GRE_TTL,
 	IFLA_GRE_TOS,
 	IFLA_GRE_PMTUDISC,
+	IFLA_GRE_ENCAP_LIMIT,
+	IFLA_GRE_FLOWINFO,
+	IFLA_GRE_FLAGS,
 	__IFLA_GRE_MAX,
 };
 
diff --git a/include/linux/ip6_tunnel.h b/include/linux/ip6_tunnel.h
index bf22b03..48af63c 100644
--- a/include/linux/ip6_tunnel.h
+++ b/include/linux/ip6_tunnel.h
@@ -31,4 +31,21 @@  struct ip6_tnl_parm {
 	struct in6_addr raddr;	/* remote tunnel end-point address */
 };
 
+struct ip6_tnl_parm2 {
+	char name[IFNAMSIZ];	/* name of tunnel device */
+	int link;		/* ifindex of underlying L2 interface */
+	__u8 proto;		/* tunnel protocol */
+	__u8 encap_limit;	/* encapsulation limit for tunnel */
+	__u8 hop_limit;		/* hop limit for tunnel */
+	__be32 flowinfo;	/* traffic class and flowlabel for tunnel */
+	__u32 flags;		/* tunnel flags */
+	struct in6_addr laddr;	/* local tunnel end-point address */
+	struct in6_addr raddr;	/* remote tunnel end-point address */
+
+	__be16			i_flags;
+	__be16			o_flags;
+	__be32			i_key;
+	__be32			o_key;
+};
+
 #endif
diff --git a/include/net/ip6_tunnel.h b/include/net/ip6_tunnel.h
index 358fb86..e03047f 100644
--- a/include/net/ip6_tunnel.h
+++ b/include/net/ip6_tunnel.h
@@ -5,6 +5,8 @@ 
 #include <linux/netdevice.h>
 #include <linux/ip6_tunnel.h>
 
+#define IP6TUNNEL_ERR_TIMEO (30*HZ)
+
 /* capable of sending packets */
 #define IP6_TNL_F_CAP_XMIT 0x10000
 /* capable of receiving packets */
@@ -12,15 +14,40 @@ 
 /* determine capability on a per-packet basis */
 #define IP6_TNL_F_CAP_PER_PACKET 0x40000
 
-/* IPv6 tunnel */
+struct __ip6_tnl_parm {
+	char name[IFNAMSIZ];	/* name of tunnel device */
+	int link;		/* ifindex of underlying L2 interface */
+	__u8 proto;		/* tunnel protocol */
+	__u8 encap_limit;	/* encapsulation limit for tunnel */
+	__u8 hop_limit;		/* hop limit for tunnel */
+	__be32 flowinfo;	/* traffic class and flowlabel for tunnel */
+	__u32 flags;		/* tunnel flags */
+	struct in6_addr laddr;	/* local tunnel end-point address */
+	struct in6_addr raddr;	/* remote tunnel end-point address */
+
+	__be16			i_flags;
+	__be16			o_flags;
+	__be32			i_key;
+	__be32			o_key;
+};
 
+/* IPv6 tunnel */
 struct ip6_tnl {
 	struct ip6_tnl __rcu *next;	/* next tunnel in list */
 	struct net_device *dev;	/* virtual device associated with tunnel */
-	struct ip6_tnl_parm parms;	/* tunnel configuration parameters */
+	struct __ip6_tnl_parm parms;	/* tunnel configuration parameters */
 	struct flowi fl;	/* flowi template for xmit */
 	struct dst_entry *dst_cache;    /* cached dst */
 	u32 dst_cookie;
+
+	int err_count;
+	unsigned long err_time;
+
+	/* These fields used only by GRE */
+	__u32 i_seqno;	/* The last seen seqno	*/
+	__u32 o_seqno;	/* The last output seqno */
+	int hlen;       /* Precalculated GRE header length */
+	int mlink;
 };
 
 /* Tunnel encapsulation limit destination sub-option */
@@ -31,4 +58,14 @@  struct ipv6_tlv_tnl_enc_lim {
 	__u8 encap_limit;	/* tunnel encapsulation limit   */
 } __packed;
 
+struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t);
+void ip6_tnl_dst_reset(struct ip6_tnl *t);
+void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst);
+int ip6_tnl_rcv_ctl(struct ip6_tnl *t, const struct in6_addr *laddr,
+		const struct in6_addr *raddr);
+int ip6_tnl_xmit_ctl(struct ip6_tnl *t);
+__u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw);
+__u32 ip6_tnl_get_cap(struct ip6_tnl *t, const struct in6_addr *laddr,
+			     const struct in6_addr *raddr);
+
 #endif
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 01c34b3..6d01fb0 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -34,6 +34,7 @@ 
 #define NEXTHDR_IPV6		41	/* IPv6 in IPv6 */
 #define NEXTHDR_ROUTING		43	/* Routing header. */
 #define NEXTHDR_FRAGMENT	44	/* Fragmentation/reassembly header. */
+#define NEXTHDR_GRE		47	/* GRE header. */
 #define NEXTHDR_ESP		50	/* Encapsulating security payload. */
 #define NEXTHDR_AUTH		51	/* Authentication header. */
 #define NEXTHDR_ICMP		58	/* ICMP for IPv6. */
diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig
index 5728695..4f7fe72 100644
--- a/net/ipv6/Kconfig
+++ b/net/ipv6/Kconfig
@@ -201,6 +201,22 @@  config IPV6_TUNNEL
 
 	  If unsure, say N.
 
+config IPV6_GRE
+	tristate "IPv6: GRE tunnel"
+	select IPV6_TUNNEL
+	---help---
+	  Tunneling means encapsulating data of one protocol type within
+	  another protocol and sending it over a channel that understands the
+	  encapsulating protocol. This particular tunneling driver implements
+	  GRE (Generic Routing Encapsulation) and at this time allows
+	  encapsulating of IPv4 or IPv6 over existing IPv6 infrastructure.
+	  This driver is useful if the other endpoint is a Cisco router: Cisco
+	  likes GRE much better than the other Linux tunneling driver ("IP
+	  tunneling" above). In addition, GRE allows multicast redistribution
+	  through the tunnel.
+
+	  Saying M here will produce a module called ip6_gre. If unsure, say 
N.
+
 config IPV6_MULTIPLE_TABLES
 	bool "IPv6: Multiple Routing Tables"
 	depends on EXPERIMENTAL
diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile
index 686934a..b6d3f79 100644
--- a/net/ipv6/Makefile
+++ b/net/ipv6/Makefile
@@ -36,6 +36,7 @@  obj-$(CONFIG_NETFILTER)	+= netfilter/
 
 obj-$(CONFIG_IPV6_SIT) += sit.o
 obj-$(CONFIG_IPV6_TUNNEL) += ip6_tunnel.o
+obj-$(CONFIG_IPV6_GRE) += ip6_gre.o
 
 obj-y += addrconf_core.o exthdrs_core.o
 
diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
new file mode 100644
index 0000000..4befedc
--- /dev/null
+++ b/net/ipv6/ip6_gre.c
@@ -0,0 +1,1791 @@ 
+/*
+ *	GRE over IPv6 protocol decoder.
+ *
+ *	Authors: Dmitry Kozlov (xeb@mail.ru)
+ *
+ *	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.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/capability.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/slab.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/in6.h>
+#include <linux/inetdevice.h>
+#include <linux/igmp.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/etherdevice.h>
+#include <linux/if_ether.h>
+#include <linux/hash.h>
+#include <linux/if_tunnel.h>
+#include <linux/ip6_tunnel.h>
+
+#include <net/sock.h>
+#include <net/ip.h>
+#include <net/icmp.h>
+#include <net/protocol.h>
+#include <net/addrconf.h>
+#include <net/arp.h>
+#include <net/checksum.h>
+#include <net/dsfield.h>
+#include <net/inet_ecn.h>
+#include <net/xfrm.h>
+#include <net/net_namespace.h>
+#include <net/netns/generic.h>
+#include <net/rtnetlink.h>
+
+#include <net/ipv6.h>
+#include <net/ip6_fib.h>
+#include <net/ip6_route.h>
+#include <net/ip6_tunnel.h>
+
+
+#define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
+#define IPV6_TCLASS_SHIFT 20
+
+#define HASH_SIZE_SHIFT  5
+#define HASH_SIZE (1 << HASH_SIZE_SHIFT)
+
+static int ip6gre_net_id __read_mostly;
+struct ip6gre_net {
+	struct ip6_tnl __rcu *tunnels[4][HASH_SIZE];
+
+	struct net_device *fb_tunnel_dev;
+};
+
+static struct rtnl_link_ops ip6gre_link_ops __read_mostly;
+static int ip6gre_tunnel_init(struct net_device *dev);
+static void ip6gre_tunnel_setup(struct net_device *dev);
+static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t);
+static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu);
+
+/* Tunnel hash table */
+
+/*
+   4 hash tables:
+
+   3: (remote,local)
+   2: (remote,*)
+   1: (*,local)
+   0: (*,*)
+
+   We require exact key match i.e. if a key is present in packet
+   it will match only tunnel with the same key; if it is not present,
+   it will match only keyless tunnel.
+
+   All keysless packets, if not matched configured keyless tunnels
+   will match fallback tunnel.
+ */
+
+#define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(HASH_SIZE - 
1))
+static u32 HASH_ADDR(const struct in6_addr *addr)
+{
+	u32 hash = ipv6_addr_hash(addr);
+
+	return hash_32(hash, HASH_SIZE_SHIFT);
+}
+
+#define tunnels_r_l	tunnels[3]
+#define tunnels_r	tunnels[2]
+#define tunnels_l	tunnels[1]
+#define tunnels_wc	tunnels[0]
+/*
+ * 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;
+};
+
+static struct rtnl_link_stats64 *ip6gre_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;
+}
+
+/* Given src, dst and key, find appropriate for input tunnel. */
+
+static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev,
+		const struct in6_addr *remote, const struct in6_addr *local,
+		__be32 key, __be16 gre_proto)
+{
+	struct net *net = dev_net(dev);
+	int link = dev->ifindex;
+	unsigned int h0 = HASH_ADDR(remote);
+	unsigned int h1 = HASH_KEY(key);
+	struct ip6_tnl *t, *cand = NULL;
+	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+	int dev_type = (gre_proto == htons(ETH_P_TEB)) ?
+		       ARPHRD_ETHER : ARPHRD_IP6GRE;
+	int score, cand_score = 4;
+
+	for_each_ip_tunnel_rcu(ign->tunnels_r_l[h0 ^ h1]) {
+		if (!ipv6_addr_equal(local, &t->parms.laddr) ||
+		    !ipv6_addr_equal(remote, &t->parms.raddr) ||
+		    key != t->parms.i_key ||
+		    !(t->dev->flags & IFF_UP))
+			continue;
+
+		if (t->dev->type != ARPHRD_IP6GRE &&
+		    t->dev->type != dev_type)
+			continue;
+
+		score = 0;
+		if (t->parms.link != link)
+			score |= 1;
+		if (t->dev->type != dev_type)
+			score |= 2;
+		if (score == 0)
+			return t;
+
+		if (score < cand_score) {
+			cand = t;
+			cand_score = score;
+		}
+	}
+
+	for_each_ip_tunnel_rcu(ign->tunnels_r[h0 ^ h1]) {
+		if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
+		    key != t->parms.i_key ||
+		    !(t->dev->flags & IFF_UP))
+			continue;
+
+		if (t->dev->type != ARPHRD_IP6GRE &&
+		    t->dev->type != dev_type)
+			continue;
+
+		score = 0;
+		if (t->parms.link != link)
+			score |= 1;
+		if (t->dev->type != dev_type)
+			score |= 2;
+		if (score == 0)
+			return t;
+
+		if (score < cand_score) {
+			cand = t;
+			cand_score = score;
+		}
+	}
+
+	for_each_ip_tunnel_rcu(ign->tunnels_l[h1]) {
+		if ((!ipv6_addr_equal(local, &t->parms.laddr) &&
+			  (!ipv6_addr_equal(local, &t->parms.raddr) ||
+				 !ipv6_addr_is_multicast(local))) ||
+		    key != t->parms.i_key ||
+		    !(t->dev->flags & IFF_UP))
+			continue;
+
+		if (t->dev->type != ARPHRD_IP6GRE &&
+		    t->dev->type != dev_type)
+			continue;
+
+		score = 0;
+		if (t->parms.link != link)
+			score |= 1;
+		if (t->dev->type != dev_type)
+			score |= 2;
+		if (score == 0)
+			return t;
+
+		if (score < cand_score) {
+			cand = t;
+			cand_score = score;
+		}
+	}
+
+	for_each_ip_tunnel_rcu(ign->tunnels_wc[h1]) {
+		if (t->parms.i_key != key ||
+		    !(t->dev->flags & IFF_UP))
+			continue;
+
+		if (t->dev->type != ARPHRD_IP6GRE &&
+		    t->dev->type != dev_type)
+			continue;
+
+		score = 0;
+		if (t->parms.link != link)
+			score |= 1;
+		if (t->dev->type != dev_type)
+			score |= 2;
+		if (score == 0)
+			return t;
+
+		if (score < cand_score) {
+			cand = t;
+			cand_score = score;
+		}
+	}
+
+	if (cand != NULL)
+		return cand;
+
+	dev = ign->fb_tunnel_dev;
+	if (dev->flags & IFF_UP)
+		return netdev_priv(dev);
+
+	return NULL;
+}
+
+static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
+		const struct __ip6_tnl_parm *p)
+{
+	const struct in6_addr *remote = &p->raddr;
+	const struct in6_addr *local = &p->laddr;
+	unsigned int h = HASH_KEY(p->i_key);
+	int prio = 0;
+
+	if (!ipv6_addr_any(local))
+		prio |= 1;
+	if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) {
+		prio |= 2;
+		h ^= HASH_ADDR(remote);
+	}
+
+	return &ign->tunnels[prio][h];
+}
+
+static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
+		const struct ip6_tnl *t)
+{
+	return __ip6gre_bucket(ign, &t->parms);
+}
+
+static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
+{
+	struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
+
+	rcu_assign_pointer(t->next, rtnl_dereference(*tp));
+	rcu_assign_pointer(*tp, t);
+}
+
+static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
+{
+	struct ip6_tnl __rcu **tp;
+	struct ip6_tnl *iter;
+
+	for (tp = ip6gre_bucket(ign, t);
+	     (iter = rtnl_dereference(*tp)) != NULL;
+	     tp = &iter->next) {
+		if (t == iter) {
+			rcu_assign_pointer(*tp, t->next);
+			break;
+		}
+	}
+}
+
+static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
+					   const struct __ip6_tnl_parm *parms,
+					   int type)
+{
+	const struct in6_addr *remote = &parms->raddr;
+	const struct in6_addr *local = &parms->laddr;
+	__be32 key = parms->i_key;
+	int link = parms->link;
+	struct ip6_tnl *t;
+	struct ip6_tnl __rcu **tp;
+	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+
+	for (tp = __ip6gre_bucket(ign, parms);
+	     (t = rtnl_dereference(*tp)) != NULL;
+	     tp = &t->next)
+		if (ipv6_addr_equal(local, &t->parms.laddr) &&
+		    ipv6_addr_equal(remote, &t->parms.raddr) &&
+		    key == t->parms.i_key &&
+		    link == t->parms.link &&
+		    type == t->dev->type)
+			break;
+
+	return t;
+}
+
+static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
+		const struct __ip6_tnl_parm *parms, int create)
+{
+	struct ip6_tnl *t, *nt;
+	struct net_device *dev;
+	char name[IFNAMSIZ];
+	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+
+	t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
+	if (t || !create)
+		return t;
+
+	if (parms->name[0])
+		strlcpy(name, parms->name, IFNAMSIZ);
+	else
+		strcpy(name, "ip6gre%d");
+
+	dev = alloc_netdev(sizeof(*t), name, ip6gre_tunnel_setup);
+	if (!dev)
+		return NULL;
+
+	dev_net_set(dev, net);
+
+	nt = netdev_priv(dev);
+	nt->parms = *parms;
+	dev->rtnl_link_ops = &ip6gre_link_ops;
+
+	nt->dev = dev;
+	ip6gre_tnl_link_config(nt, 1);
+
+	if (register_netdevice(dev) < 0)
+		goto failed_free;
+
+	/* Can use a lockless transmit, unless we generate output sequences */
+	if (!(nt->parms.o_flags & GRE_SEQ))
+		dev->features |= NETIF_F_LLTX;
+
+	dev_hold(dev);
+	ip6gre_tunnel_link(ign, nt);
+	return nt;
+
+failed_free:
+	free_netdev(dev);
+	return NULL;
+}
+
+static void ip6gre_tunnel_uninit(struct net_device *dev)
+{
+	struct net *net = dev_net(dev);
+	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+
+	ip6gre_tunnel_unlink(ign, netdev_priv(dev));
+	dev_put(dev);
+}
+
+
+static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
+		u8 type, u8 code, int offset, __be32 info)
+{
+	const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data;
+	__be16 *p = (__be16 *)(ipv6h + 1);
+	int grehlen = sizeof(ipv6h) + 4;
+	struct ip6_tnl *t;
+	__be16 flags;
+
+	flags = p[0];
+	if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) {
+		if (flags&(GRE_VERSION|GRE_ROUTING))
+			return;
+		if (flags&GRE_KEY) {
+			grehlen += 4;
+			if (flags&GRE_CSUM)
+				grehlen += 4;
+		}
+	}
+
+	/* If only 8 bytes returned, keyed message will be dropped here */
+	if (skb_headlen(skb) < grehlen)
+		return;
+
+	rcu_read_lock();
+
+	t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
+				flags & GRE_KEY ?
+				*(((__be32 *)p) + (grehlen / 4) - 1) : 0,
+				p[1]);
+	if (t == NULL)
+		goto out;
+
+	switch (type) {
+		__u32 teli;
+		struct ipv6_tlv_tnl_enc_lim *tel;
+		__u32 mtu;
+	case ICMPV6_DEST_UNREACH:
+		net_warn_ratelimited("%s: Path to destination invalid or 
inactive!\n",
+				     t->parms.name);
+		break;
+	case ICMPV6_TIME_EXCEED:
+		if (code == ICMPV6_EXC_HOPLIMIT) {
+			net_warn_ratelimited("%s: Too small hop limit or 
routing loop in tunnel!\n",
+					     t->parms.name);
+		}
+		break;
+	case ICMPV6_PARAMPROB:
+		teli = 0;
+		if (code == ICMPV6_HDR_FIELD)
+			teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
+
+		if (teli && teli == info - 2) {
+			tel = (struct ipv6_tlv_tnl_enc_lim *) &skb-
>data[teli];
+			if (tel->encap_limit == 0) {
+				net_warn_ratelimited("%s: Too small 
encapsulation limit or routing loop in tunnel!\n",
+						     t->parms.name);
+			}
+		} else {
+			net_warn_ratelimited("%s: Recipient unable to parse 
tunneled packet!\n",
+					     t->parms.name);
+		}
+		break;
+	case ICMPV6_PKT_TOOBIG:
+		mtu = info - offset;
+		if (mtu < IPV6_MIN_MTU)
+			mtu = IPV6_MIN_MTU;
+		t->dev->mtu = mtu;
+		break;
+	}
+
+	if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
+		t->err_count++;
+	else
+		t->err_count = 1;
+	t->err_time = jiffies;
+out:
+	rcu_read_unlock();
+}
+
+static inline void ip6gre_ecn_decapsulate_ipv4(const struct ip6_tnl *t,
+		const struct ipv6hdr *ipv6h, struct sk_buff *skb)
+{
+	__u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
+
+	if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
+		ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
+
+	if (INET_ECN_is_ce(dsfield))
+		IP_ECN_set_ce(ip_hdr(skb));
+}
+
+static inline void ip6gre_ecn_decapsulate_ipv6(const struct ip6_tnl *t,
+		const struct ipv6hdr *ipv6h, struct sk_buff *skb)
+{
+	if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
+		ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
+
+	if (INET_ECN_is_ce(ipv6_get_dsfield(ipv6h)))
+		IP6_ECN_set_ce(ipv6_hdr(skb));
+}
+
+static int ip6gre_rcv(struct sk_buff *skb)
+{
+	const struct ipv6hdr *ipv6h;
+	u8     *h;
+	__be16    flags;
+	__sum16   csum = 0;
+	__be32 key = 0;
+	u32    seqno = 0;
+	struct ip6_tnl *tunnel;
+	int    offset = 4;
+	__be16 gre_proto;
+
+	if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
+		goto drop_nolock;
+
+	ipv6h = ipv6_hdr(skb);
+	h = skb->data;
+	flags = *(__be16 *)h;
+
+	if (flags&(GRE_CSUM|GRE_KEY|GRE_ROUTING|GRE_SEQ|GRE_VERSION)) {
+		/* - Version must be 0.
+		   - We do not support routing headers.
+		 */
+		if (flags&(GRE_VERSION|GRE_ROUTING))
+			goto drop_nolock;
+
+		if (flags&GRE_CSUM) {
+			switch (skb->ip_summed) {
+			case CHECKSUM_COMPLETE:
+				csum = csum_fold(skb->csum);
+				if (!csum)
+					break;
+				/* fall through */
+			case CHECKSUM_NONE:
+				skb->csum = 0;
+				csum = __skb_checksum_complete(skb);
+				skb->ip_summed = CHECKSUM_COMPLETE;
+			}
+			offset += 4;
+		}
+		if (flags&GRE_KEY) {
+			key = *(__be32 *)(h + offset);
+			offset += 4;
+		}
+		if (flags&GRE_SEQ) {
+			seqno = ntohl(*(__be32 *)(h + offset));
+			offset += 4;
+		}
+	}
+
+	gre_proto = *(__be16 *)(h + 2);
+
+	rcu_read_lock();
+	tunnel = ip6gre_tunnel_lookup(skb->dev,
+					  &ipv6h->saddr, &ipv6h->daddr, key,
+					  gre_proto);
+	if (tunnel) {
+		struct pcpu_tstats *tstats;
+
+		if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
+			goto drop;
+
+		if (!ip6_tnl_rcv_ctl(tunnel, &ipv6h->daddr, &ipv6h->saddr)) {
+			tunnel->dev->stats.rx_dropped++;
+			goto drop;
+		}
+
+		secpath_reset(skb);
+
+		skb->protocol = gre_proto;
+		/* WCCP version 1 and 2 protocol decoding.
+		 * - Change protocol to IP
+		 * - When dealing with WCCPv2, Skip extra 4 bytes in GRE 
header
+		 */
+		if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) {
+			skb->protocol = htons(ETH_P_IP);
+			if ((*(h + offset) & 0xF0) != 0x40)
+				offset += 4;
+		}
+
+		skb->mac_header = skb->network_header;
+		__pskb_pull(skb, offset);
+		skb_postpull_rcsum(skb, skb_transport_header(skb), offset);
+		skb->pkt_type = PACKET_HOST;
+
+		if (((flags&GRE_CSUM) && csum) ||
+		    (!(flags&GRE_CSUM) && tunnel->parms.i_flags&GRE_CSUM)) {
+			tunnel->dev->stats.rx_crc_errors++;
+			tunnel->dev->stats.rx_errors++;
+			goto drop;
+		}
+		if (tunnel->parms.i_flags&GRE_SEQ) {
+			if (!(flags&GRE_SEQ) ||
+			    (tunnel->i_seqno &&
+					(s32)(seqno - tunnel->i_seqno) < 0)) {
+				tunnel->dev->stats.rx_fifo_errors++;
+				tunnel->dev->stats.rx_errors++;
+				goto drop;
+			}
+			tunnel->i_seqno = seqno + 1;
+		}
+
+		/* Warning: All skb pointers will be invalidated! */
+		if (tunnel->dev->type == ARPHRD_ETHER) {
+			if (!pskb_may_pull(skb, ETH_HLEN)) {
+				tunnel->dev->stats.rx_length_errors++;
+				tunnel->dev->stats.rx_errors++;
+				goto drop;
+			}
+
+			ipv6h = ipv6_hdr(skb);
+			skb->protocol = eth_type_trans(skb, tunnel->dev);
+			skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
+		}
+
+		tstats = this_cpu_ptr(tunnel->dev->tstats);
+		u64_stats_update_begin(&tstats->syncp);
+		tstats->rx_packets++;
+		tstats->rx_bytes += skb->len;
+		u64_stats_update_end(&tstats->syncp);
+
+		__skb_tunnel_rx(skb, tunnel->dev);
+
+		skb_reset_network_header(skb);
+		if (skb->protocol == htons(ETH_P_IP))
+			ip6gre_ecn_decapsulate_ipv4(tunnel, ipv6h, skb);
+		else if (skb->protocol == htons(ETH_P_IPV6))
+			ip6gre_ecn_decapsulate_ipv6(tunnel, ipv6h, skb);
+
+		netif_rx(skb);
+
+		rcu_read_unlock();
+		return 0;
+	}
+	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
+
+drop:
+	rcu_read_unlock();
+drop_nolock:
+	kfree_skb(skb);
+	return 0;
+}
+
+struct ipv6_tel_txoption {
+	struct ipv6_txoptions ops;
+	__u8 dst_opt[8];
+};
+
+static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
+{
+	memset(opt, 0, sizeof(struct ipv6_tel_txoption));
+
+	opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
+	opt->dst_opt[3] = 1;
+	opt->dst_opt[4] = encap_limit;
+	opt->dst_opt[5] = IPV6_TLV_PADN;
+	opt->dst_opt[6] = 1;
+
+	opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt;
+	opt->ops.opt_nflen = 8;
+}
+
+static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb,
+			 struct net_device *dev,
+			 __u8 dsfield,
+			 struct flowi6 *fl6,
+			 int encap_limit,
+			 __u32 *pmtu)
+{
+	struct net *net = dev_net(dev);
+	struct ip6_tnl *tunnel = netdev_priv(dev);
+	struct net_device *tdev;    /* Device to other host */
+	struct ipv6hdr  *ipv6h;     /* Our new IP header */
+	unsigned int max_headroom;  /* The extra header space needed */
+	int    gre_hlen;
+	struct ipv6_tel_txoption opt;
+	int    mtu;
+	struct dst_entry *dst = NULL, *ndst = NULL;
+	struct net_device_stats *stats = &tunnel->dev->stats;
+	int err = -1;
+	u8 proto;
+	int pkt_len;
+	struct sk_buff *new_skb;
+
+	if (dev->type == ARPHRD_ETHER)
+		IPCB(skb)->flags = 0;
+
+	if (dev->header_ops && dev->type == ARPHRD_IP6GRE) {
+		gre_hlen = 0;
+		ipv6h = (struct ipv6hdr *)skb->data;
+		fl6->daddr = ipv6h->daddr;
+	} else {
+		gre_hlen = tunnel->hlen;
+		fl6->daddr = tunnel->parms.raddr;
+	}
+
+	if (!fl6->flowi6_mark)
+		dst = ip6_tnl_dst_check(tunnel);
+
+	if (!dst) {
+		ndst = ip6_route_output(net, NULL, fl6);
+
+		if (ndst->error)
+			goto tx_err_link_failure;
+		ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0);
+		if (IS_ERR(ndst)) {
+			err = PTR_ERR(ndst);
+			ndst = NULL;
+			goto tx_err_link_failure;
+		}
+		dst = ndst;
+	}
+
+	tdev = dst->dev;
+
+	if (tdev == dev) {
+		stats->collisions++;
+		net_warn_ratelimited("%s: Local routing loop detected!\n",
+				     tunnel->parms.name);
+		goto tx_err_dst_release;
+	}
+
+	mtu = dst_mtu(dst) - sizeof(*ipv6h);
+	if (encap_limit >= 0) {
+		max_headroom += 8;
+		mtu -= 8;
+	}
+	if (mtu < IPV6_MIN_MTU)
+		mtu = IPV6_MIN_MTU;
+	if (skb_dst(skb))
+		skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
+	if (skb->len > mtu) {
+		*pmtu = mtu;
+		err = -EMSGSIZE;
+		goto tx_err_dst_release;
+	}
+
+	if (tunnel->err_count > 0) {
+		if (time_before(jiffies,
+				tunnel->err_time + IP6TUNNEL_ERR_TIMEO)) {
+			tunnel->err_count--;
+
+			dst_link_failure(skb);
+		} else
+			tunnel->err_count = 0;
+	}
+
+	max_headroom = LL_RESERVED_SPACE(tdev) + gre_hlen + dst->header_len;
+
+	if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
+	    (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
+		new_skb = skb_realloc_headroom(skb, max_headroom);
+		if (max_headroom > dev->needed_headroom)
+			dev->needed_headroom = max_headroom;
+		if (!new_skb)
+			goto tx_err_dst_release;
+
+		if (skb->sk)
+			skb_set_owner_w(new_skb, skb->sk);
+		consume_skb(skb);
+		skb = new_skb;
+	}
+
+	skb_dst_drop(skb);
+
+	if (fl6->flowi6_mark) {
+		skb_dst_set(skb, dst);
+		ndst = NULL;
+	} else {
+		skb_dst_set_noref(skb, dst);
+	}
+
+	skb->transport_header = skb->network_header;
+
+	proto = NEXTHDR_GRE;
+	if (encap_limit >= 0) {
+		init_tel_txopt(&opt, encap_limit);
+		ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
+	}
+
+	skb_push(skb, gre_hlen);
+	skb_reset_network_header(skb);
+
+	/*
+	 *	Push down and install the IP header.
+	 */
+	ipv6h = ipv6_hdr(skb);
+	*(__be32 *)ipv6h = fl6->flowlabel | htonl(0x60000000);
+	dsfield = INET_ECN_encapsulate(0, dsfield);
+	ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield);
+	ipv6h->hop_limit = tunnel->parms.hop_limit;
+	ipv6h->nexthdr = proto;
+	ipv6h->saddr = fl6->saddr;
+	ipv6h->daddr = fl6->daddr;
+
+	((__be16 *)(ipv6h + 1))[0] = tunnel->parms.o_flags;
+	((__be16 *)(ipv6h + 1))[1] = (dev->type == ARPHRD_ETHER) ?
+				   htons(ETH_P_TEB) : skb->protocol;
+
+	if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) {
+		__be32 *ptr = (__be32 *)(((u8 *)ipv6h) + tunnel->hlen - 4);
+
+		if (tunnel->parms.o_flags&GRE_SEQ) {
+			++tunnel->o_seqno;
+			*ptr = htonl(tunnel->o_seqno);
+			ptr--;
+		}
+		if (tunnel->parms.o_flags&GRE_KEY) {
+			*ptr = tunnel->parms.o_key;
+			ptr--;
+		}
+		if (tunnel->parms.o_flags&GRE_CSUM) {
+			*ptr = 0;
+			*(__sum16 *)ptr = ip_compute_csum((void *)(ipv6h+1),
+				skb->len - sizeof(struct ipv6hdr));
+		}
+	}
+
+	nf_reset(skb);
+	pkt_len = skb->len;
+	err = ip6_local_out(skb);
+
+	if (net_xmit_eval(err) == 0) {
+		struct pcpu_tstats *tstats = this_cpu_ptr(tunnel->dev-
>tstats);
+
+		tstats->tx_bytes += pkt_len;
+		tstats->tx_packets++;
+	} else {
+		stats->tx_errors++;
+		stats->tx_aborted_errors++;
+	}
+
+	if (ndst)
+		ip6_tnl_dst_store(tunnel, ndst);
+
+	return 0;
+tx_err_link_failure:
+	stats->tx_carrier_errors++;
+	dst_link_failure(skb);
+tx_err_dst_release:
+	dst_release(ndst);
+	return err;
+}
+
+static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device 
*dev)
+{
+	struct ip6_tnl *t = netdev_priv(dev);
+	const struct iphdr  *iph = ip_hdr(skb);
+	int encap_limit = -1;
+	struct flowi6 fl6;
+	__u8 dsfield;
+	__u32 mtu;
+	int err;
+
+	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
+		encap_limit = t->parms.encap_limit;
+
+	memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
+	fl6.flowi6_proto = IPPROTO_IPIP;
+
+	dsfield = ipv4_get_dsfield(iph);
+
+	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
+		fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT)
+					  & IPV6_TCLASS_MASK;
+	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
+		fl6.flowi6_mark = skb->mark;
+
+	err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
+	if (err != 0) {
+		/* XXX: send ICMP error even if DF is not set. */
+		if (err == -EMSGSIZE)
+			icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
+				  htonl(mtu));
+		return -1;
+	}
+
+	return 0;
+}
+
+static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device 
*dev)
+{
+	struct ip6_tnl *t = netdev_priv(dev);
+	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
+	int encap_limit = -1;
+	__u16 offset;
+	struct flowi6 fl6;
+	__u8 dsfield;
+	__u32 mtu;
+	int err;
+
+	if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
+		return -1;
+
+	offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
+	if (offset > 0) {
+		struct ipv6_tlv_tnl_enc_lim *tel;
+		tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)
[offset];
+		if (tel->encap_limit == 0) {
+			icmpv6_send(skb, ICMPV6_PARAMPROB,
+				    ICMPV6_HDR_FIELD, offset + 2);
+			return -1;
+		}
+		encap_limit = tel->encap_limit - 1;
+	} else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
+		encap_limit = t->parms.encap_limit;
+
+	memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
+	fl6.flowi6_proto = IPPROTO_IPV6;
+
+	dsfield = ipv6_get_dsfield(ipv6h);
+	if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
+		fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK);
+	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
+		fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK);
+	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
+		fl6.flowi6_mark = skb->mark;
+
+	err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
+	if (err != 0) {
+		if (err == -EMSGSIZE)
+			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
+		return -1;
+	}
+
+	return 0;
+}
+
+/**
+ * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
+ *   @t: the outgoing tunnel device
+ *   @hdr: IPv6 header from the incoming packet
+ *
+ * Description:
+ *   Avoid trivial tunneling loop by checking that tunnel exit-point
+ *   doesn't match source of incoming packet.
+ *
+ * Return:
+ *   1 if conflict,
+ *   0 else
+ **/
+
+static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t,
+	const struct ipv6hdr *hdr)
+{
+	return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
+}
+
+static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
+{
+	struct ip6_tnl *t = netdev_priv(dev);
+	int encap_limit = -1;
+	struct flowi6 fl6;
+	__u32 mtu;
+	int err;
+
+	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
+		encap_limit = t->parms.encap_limit;
+
+	memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
+	fl6.flowi6_proto = skb->protocol;
+
+	err = ip6gre_xmit2(skb, dev, 0, &fl6, encap_limit, &mtu);
+
+	return err;
+}
+
+static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
+	struct net_device *dev)
+{
+	struct ip6_tnl *t = netdev_priv(dev);
+	struct net_device_stats *stats = &t->dev->stats;
+	int ret;
+
+	if (!ip6_tnl_xmit_ctl(t))
+		return -1;
+
+	switch (skb->protocol) {
+	case htons(ETH_P_IP):
+		ret = ip6gre_xmit_ipv4(skb, dev);
+		break;
+	case htons(ETH_P_IPV6):
+		ret = ip6gre_xmit_ipv6(skb, dev);
+		break;
+	default:
+		ret = ip6gre_xmit_other(skb, dev);
+		break;
+	}
+
+	if (ret < 0)
+		goto tx_err;
+
+	return NETDEV_TX_OK;
+
+tx_err:
+	stats->tx_errors++;
+	stats->tx_dropped++;
+	kfree_skb(skb);
+	return NETDEV_TX_OK;
+}
+
+static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
+{
+	struct net_device *dev = t->dev;
+	struct __ip6_tnl_parm *p = &t->parms;
+	struct flowi6 *fl6 = &t->fl.u.ip6;
+	int addend = sizeof(struct ipv6hdr) + 4;
+
+	if (dev->type != ARPHRD_ETHER) {
+		memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
+		memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
+	}
+
+	/* Set up flowi template */
+	fl6->saddr = p->laddr;
+	fl6->daddr = p->raddr;
+	fl6->flowi6_oif = p->link;
+	fl6->flowlabel = 0;
+
+	if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
+		fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
+	if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
+		fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
+
+	p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|
IP6_TNL_F_CAP_PER_PACKET);
+	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
+
+	if (p->flags&IP6_TNL_F_CAP_XMIT &&
+			p->flags&IP6_TNL_F_CAP_RCV && dev->type != 
ARPHRD_ETHER)
+		dev->flags |= IFF_POINTOPOINT;
+	else
+		dev->flags &= ~IFF_POINTOPOINT;
+
+	dev->iflink = p->link;
+
+	/* Precalculate GRE options length */
+	if (t->parms.o_flags&(GRE_CSUM|GRE_KEY|GRE_SEQ)) {
+		if (t->parms.o_flags&GRE_CSUM)
+			addend += 4;
+		if (t->parms.o_flags&GRE_KEY)
+			addend += 4;
+		if (t->parms.o_flags&GRE_SEQ)
+			addend += 4;
+	}
+
+	if (p->flags & IP6_TNL_F_CAP_XMIT) {
+		int strict = (ipv6_addr_type(&p->raddr) &
+			      (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
+
+		struct rt6_info *rt = rt6_lookup(dev_net(dev),
+						 &p->raddr, &p->laddr,
+						 p->link, strict);
+
+		if (rt == NULL)
+			return;
+
+		if (rt->dst.dev) {
+			dev->hard_header_len = rt->dst.dev->hard_header_len + 
addend;
+
+			if (set_mtu) {
+				dev->mtu = rt->dst.dev->mtu - addend;
+				if (!(t->parms.flags & 
IP6_TNL_F_IGN_ENCAP_LIMIT))
+					dev->mtu -= 8;
+
+				if (dev->mtu < IPV6_MIN_MTU)
+					dev->mtu = IPV6_MIN_MTU;
+			}
+		}
+		dst_release(&rt->dst);
+	}
+
+	t->hlen = addend;
+}
+
+static int ip6gre_tnl_change(struct ip6_tnl *t,
+	const struct __ip6_tnl_parm *p, int set_mtu)
+{
+	t->parms.laddr = p->laddr;
+	t->parms.raddr = p->raddr;
+	t->parms.flags = p->flags;
+	t->parms.hop_limit = p->hop_limit;
+	t->parms.encap_limit = p->encap_limit;
+	t->parms.flowinfo = p->flowinfo;
+	t->parms.link = p->link;
+	t->parms.proto = p->proto;
+	t->parms.i_key = p->i_key;
+	t->parms.o_key = p->o_key;
+	t->parms.i_flags = p->i_flags;
+	t->parms.o_flags = p->o_flags;
+	ip6_tnl_dst_reset(t);
+	ip6gre_tnl_link_config(t, set_mtu);
+	return 0;
+}
+
+static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
+	const struct ip6_tnl_parm2 *u)
+{
+	p->laddr = u->laddr;
+	p->raddr = u->raddr;
+	p->flags = u->flags;
+	p->hop_limit = u->hop_limit;
+	p->encap_limit = u->encap_limit;
+	p->flowinfo = u->flowinfo;
+	p->link = u->link;
+	p->i_key = u->i_key;
+	p->o_key = u->o_key;
+	p->i_flags = u->i_flags;
+	p->o_flags = u->o_flags;
+	memcpy(p->name, u->name, sizeof(u->name));
+}
+
+static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
+	const struct __ip6_tnl_parm *p)
+{
+	u->proto = IPPROTO_GRE;
+	u->laddr = p->laddr;
+	u->raddr = p->raddr;
+	u->flags = p->flags;
+	u->hop_limit = p->hop_limit;
+	u->encap_limit = p->encap_limit;
+	u->flowinfo = p->flowinfo;
+	u->link = p->link;
+	u->i_key = p->i_key;
+	u->o_key = p->o_key;
+	u->i_flags = p->i_flags;
+	u->o_flags = p->o_flags;
+	memcpy(u->name, p->name, sizeof(u->name));
+}
+
+static int ip6gre_tunnel_ioctl(struct net_device *dev,
+	struct ifreq *ifr, int cmd)
+{
+	int err = 0;
+	struct ip6_tnl_parm2 p;
+	struct __ip6_tnl_parm p1;
+	struct ip6_tnl *t;
+	struct net *net = dev_net(dev);
+	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+
+	switch (cmd) {
+	case SIOCGETTUNNEL:
+		t = NULL;
+		if (dev == ign->fb_tunnel_dev) {
+			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, 
sizeof(p))) {
+				err = -EFAULT;
+				break;
+			}
+			ip6gre_tnl_parm_from_user(&p1, &p);
+			t = ip6gre_tunnel_locate(net, &p1, 0);
+		}
+		if (t == NULL)
+			t = netdev_priv(dev);
+		ip6gre_tnl_parm_to_user(&p, &t->parms);
+		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.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
+			goto done;
+
+		if (!(p.i_flags&GRE_KEY))
+			p.i_key = 0;
+		if (!(p.o_flags&GRE_KEY))
+			p.o_key = 0;
+
+		ip6gre_tnl_parm_from_user(&p1, &p);
+		t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
+
+		if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
+			if (t != NULL) {
+				if (t->dev != dev) {
+					err = -EEXIST;
+					break;
+				}
+			} else {
+				t = netdev_priv(dev);
+
+				ip6gre_tunnel_unlink(ign, t);
+				synchronize_net();
+				ip6gre_tnl_change(t, &p1, 1);
+				ip6gre_tunnel_link(ign, t);
+				netdev_state_change(dev);
+			}
+		}
+
+		if (t) {
+			err = 0;
+
+			ip6gre_tnl_parm_to_user(&p, &t->parms);
+			if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, 
sizeof(p)))
+				err = -EFAULT;
+		} else
+			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
+		break;
+
+	case SIOCDELTUNNEL:
+		err = -EPERM;
+		if (!capable(CAP_NET_ADMIN))
+			goto done;
+
+		if (dev == ign->fb_tunnel_dev) {
+			err = -EFAULT;
+			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, 
sizeof(p)))
+				goto done;
+			err = -ENOENT;
+			ip6gre_tnl_parm_from_user(&p1, &p);
+			t = ip6gre_tunnel_locate(net, &p1, 0);
+			if (t == NULL)
+				goto done;
+			err = -EPERM;
+			if (t == netdev_priv(ign->fb_tunnel_dev))
+				goto done;
+			dev = t->dev;
+		}
+		unregister_netdevice(dev);
+		err = 0;
+		break;
+
+	default:
+		err = -EINVAL;
+	}
+
+done:
+	return err;
+}
+
+static int ip6gre_tunnel_change_mtu(struct net_device *dev, int new_mtu)
+{
+	struct ip6_tnl *tunnel = netdev_priv(dev);
+	if (new_mtu < 68 ||
+	    new_mtu > 0xFFF8 - dev->hard_header_len - tunnel->hlen)
+		return -EINVAL;
+	dev->mtu = new_mtu;
+	return 0;
+}
+
+static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
+			unsigned short type,
+			const void *daddr, const void *saddr, unsigned int 
len)
+{
+	struct ip6_tnl *t = netdev_priv(dev);
+	struct ipv6hdr *ipv6h = (struct ipv6hdr *)skb_push(skb, t->hlen);
+	__be16 *p = (__be16 *)(ipv6h+1);
+
+	*(__be32 *)ipv6h = t->fl.u.ip6.flowlabel | htonl(0x60000000);
+	ipv6h->hop_limit = t->parms.hop_limit;
+	ipv6h->nexthdr = NEXTHDR_GRE;
+	ipv6h->saddr = t->parms.laddr;
+	ipv6h->daddr = t->parms.raddr;
+
+	p[0]		= t->parms.o_flags;
+	p[1]		= htons(type);
+
+	/*
+	 *	Set the source hardware address.
+	 */
+
+	if (saddr)
+		memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
+	if (daddr)
+		memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
+	if (!ipv6_addr_any(&ipv6h->daddr))
+		return t->hlen;
+
+	return -t->hlen;
+}
+
+static int ip6gre_header_parse(const struct sk_buff *skb, unsigned char 
*haddr)
+{
+	const struct ipv6hdr *ipv6h = (const struct ipv6hdr 
*)skb_mac_header(skb);
+	memcpy(haddr, &ipv6h->saddr, sizeof(struct in6_addr));
+	return sizeof(struct in6_addr);
+}
+
+static const struct header_ops ip6gre_header_ops = {
+	.create	= ip6gre_header,
+	.parse	= ip6gre_header_parse,
+};
+
+static const struct net_device_ops ip6gre_netdev_ops = {
+	.ndo_init		= ip6gre_tunnel_init,
+	.ndo_uninit		= ip6gre_tunnel_uninit,
+	.ndo_start_xmit		= ip6gre_tunnel_xmit,
+	.ndo_do_ioctl		= ip6gre_tunnel_ioctl,
+	.ndo_change_mtu		= ip6gre_tunnel_change_mtu,
+	.ndo_get_stats64	= ip6gre_get_stats64,
+};
+
+static void ip6gre_dev_free(struct net_device *dev)
+{
+	free_percpu(dev->tstats);
+	free_netdev(dev);
+}
+
+static void ip6gre_tunnel_setup(struct net_device *dev)
+{
+	struct ip6_tnl *t;
+
+	dev->netdev_ops = &ip6gre_netdev_ops;
+	dev->destructor = ip6gre_dev_free;
+
+	dev->type = ARPHRD_IP6GRE;
+	dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr) + 4;
+	dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr) - 4;
+	t = netdev_priv(dev);
+	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
+		dev->mtu -= 8;
+	dev->flags |= IFF_NOARP;
+	dev->iflink = 0;
+	dev->addr_len = sizeof(struct in6_addr);
+	dev->features |= NETIF_F_NETNS_LOCAL;
+	dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
+}
+
+static int ip6gre_tunnel_init(struct net_device *dev)
+{
+	struct ip6_tnl *tunnel;
+
+	tunnel = netdev_priv(dev);
+
+	tunnel->dev = dev;
+	strcpy(tunnel->parms.name, dev->name);
+
+	memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr));
+	memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
+
+	if (ipv6_addr_any(&tunnel->parms.raddr))
+		dev->header_ops = &ip6gre_header_ops;
+
+	dev->tstats = alloc_percpu(struct pcpu_tstats);
+	if (!dev->tstats)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static void ip6gre_fb_tunnel_init(struct net_device *dev)
+{
+	struct ip6_tnl *tunnel = netdev_priv(dev);
+
+	tunnel->dev = dev;
+	strcpy(tunnel->parms.name, dev->name);
+
+	tunnel->hlen		= sizeof(struct ipv6hdr) + 4;
+
+	dev_hold(dev);
+}
+
+
+static struct inet6_protocol ip6gre_protocol __read_mostly = {
+	.handler     = ip6gre_rcv,
+	.err_handler = ip6gre_err,
+	.flags       = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
+};
+
+static void ip6gre_destroy_tunnels(struct ip6gre_net *ign,
+	struct list_head *head)
+{
+	int prio;
+
+	for (prio = 0; prio < 4; prio++) {
+		int h;
+		for (h = 0; h < HASH_SIZE; h++) {
+			struct ip6_tnl *t;
+
+			t = rtnl_dereference(ign->tunnels[prio][h]);
+
+			while (t != NULL) {
+				unregister_netdevice_queue(t->dev, head);
+				t = rtnl_dereference(t->next);
+			}
+		}
+	}
+}
+
+static int __net_init ip6gre_init_net(struct net *net)
+{
+	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+	int err;
+
+	ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
+					   ip6gre_tunnel_setup);
+	if (!ign->fb_tunnel_dev) {
+		err = -ENOMEM;
+		goto err_alloc_dev;
+	}
+	dev_net_set(ign->fb_tunnel_dev, net);
+
+	ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
+	ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
+
+	err = register_netdev(ign->fb_tunnel_dev);
+	if (err)
+		goto err_reg_dev;
+
+	rcu_assign_pointer(ign->tunnels_wc[0],
+			   netdev_priv(ign->fb_tunnel_dev));
+	return 0;
+
+err_reg_dev:
+	ip6gre_dev_free(ign->fb_tunnel_dev);
+err_alloc_dev:
+	return err;
+}
+
+static void __net_exit ip6gre_exit_net(struct net *net)
+{
+	struct ip6gre_net *ign;
+	LIST_HEAD(list);
+
+	ign = net_generic(net, ip6gre_net_id);
+	rtnl_lock();
+	ip6gre_destroy_tunnels(ign, &list);
+	unregister_netdevice_many(&list);
+	rtnl_unlock();
+}
+
+static struct pernet_operations ip6gre_net_ops = {
+	.init = ip6gre_init_net,
+	.exit = ip6gre_exit_net,
+	.id   = &ip6gre_net_id,
+	.size = sizeof(struct ip6gre_net),
+};
+
+static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[])
+{
+	__be16 flags;
+
+	if (!data)
+		return 0;
+
+	flags = 0;
+	if (data[IFLA_GRE_IFLAGS])
+		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
+	if (data[IFLA_GRE_OFLAGS])
+		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
+	if (flags & (GRE_VERSION|GRE_ROUTING))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[])
+{
+	struct in6_addr daddr;
+
+	if (tb[IFLA_ADDRESS]) {
+		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
+			return -EINVAL;
+		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
+			return -EADDRNOTAVAIL;
+	}
+
+	if (!data)
+		goto out;
+
+	if (data[IFLA_GRE_REMOTE]) {
+		nla_memcpy(&daddr, data[IFLA_GRE_REMOTE], sizeof(struct 
in6_addr));
+		if (ipv6_addr_any(&daddr))
+			return -EINVAL;
+	}
+
+out:
+	return ip6gre_tunnel_validate(tb, data);
+}
+
+
+static void ip6gre_netlink_parms(struct nlattr *data[],
+				struct __ip6_tnl_parm *parms)
+{
+	memset(parms, 0, sizeof(*parms));
+
+	if (!data)
+		return;
+
+	if (data[IFLA_GRE_LINK])
+		parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
+
+	if (data[IFLA_GRE_IFLAGS])
+		parms->i_flags = nla_get_be16(data[IFLA_GRE_IFLAGS]);
+
+	if (data[IFLA_GRE_OFLAGS])
+		parms->o_flags = nla_get_be16(data[IFLA_GRE_OFLAGS]);
+
+	if (data[IFLA_GRE_IKEY])
+		parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
+
+	if (data[IFLA_GRE_OKEY])
+		parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
+
+	if (data[IFLA_GRE_LOCAL])
+		nla_memcpy(&parms->laddr, data[IFLA_GRE_LOCAL], sizeof(struct 
in6_addr));
+
+	if (data[IFLA_GRE_REMOTE])
+		nla_memcpy(&parms->raddr, data[IFLA_GRE_REMOTE], sizeof(struct 
in6_addr));
+
+	if (data[IFLA_GRE_TTL])
+		parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
+
+	if (data[IFLA_GRE_ENCAP_LIMIT])
+		parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
+
+	if (data[IFLA_GRE_FLOWINFO])
+		parms->flowinfo = nla_get_u32(data[IFLA_GRE_FLOWINFO]);
+
+	if (data[IFLA_GRE_FLAGS])
+		parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
+}
+
+static int ip6gre_tap_init(struct net_device *dev)
+{
+	struct ip6_tnl *tunnel;
+
+	tunnel = netdev_priv(dev);
+
+	tunnel->dev = dev;
+	strcpy(tunnel->parms.name, dev->name);
+
+	ip6gre_tnl_link_config(tunnel, 1);
+
+	dev->tstats = alloc_percpu(struct pcpu_tstats);
+	if (!dev->tstats)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static const struct net_device_ops ip6gre_tap_netdev_ops = {
+	.ndo_init = ip6gre_tap_init,
+	.ndo_uninit = ip6gre_tunnel_uninit,
+	.ndo_start_xmit = ip6gre_tunnel_xmit,
+	.ndo_set_mac_address = eth_mac_addr,
+	.ndo_validate_addr = eth_validate_addr,
+	.ndo_change_mtu = ip6gre_tunnel_change_mtu,
+	.ndo_get_stats64 = ip6gre_get_stats64,
+};
+
+static void ip6gre_tap_setup(struct net_device *dev)
+{
+
+	ether_setup(dev);
+
+	dev->netdev_ops = &ip6gre_tap_netdev_ops;
+	dev->destructor = ip6gre_dev_free;
+
+	dev->iflink = 0;
+	dev->features |= NETIF_F_NETNS_LOCAL;
+}
+
+static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
+	struct nlattr *tb[], struct nlattr *data[])
+{
+	struct ip6_tnl *nt;
+	struct net *net = dev_net(dev);
+	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+	int err;
+
+	nt = netdev_priv(dev);
+	ip6gre_netlink_parms(data, &nt->parms);
+
+	if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
+		return -EEXIST;
+
+	if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
+		eth_hw_addr_random(dev);
+
+	nt->dev = dev;
+	ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
+
+	/* Can use a lockless transmit, unless we generate output sequences */
+	if (!(nt->parms.o_flags & GRE_SEQ))
+		dev->features |= NETIF_F_LLTX;
+
+	err = register_netdevice(dev);
+	if (err)
+		goto out;
+
+	dev_hold(dev);
+	ip6gre_tunnel_link(ign, nt);
+
+out:
+	return err;
+}
+
+static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
+			    struct nlattr *data[])
+{
+	struct ip6_tnl *t, *nt;
+	struct net *net = dev_net(dev);
+	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
+	struct __ip6_tnl_parm p;
+
+	if (dev == ign->fb_tunnel_dev)
+		return -EINVAL;
+
+	nt = netdev_priv(dev);
+	ip6gre_netlink_parms(data, &p);
+
+	t = ip6gre_tunnel_locate(net, &p, 0);
+
+	if (t) {
+		if (t->dev != dev)
+			return -EEXIST;
+	} else {
+		t = nt;
+
+		ip6gre_tunnel_unlink(ign, t);
+		ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
+		ip6gre_tunnel_link(ign, t);
+		netdev_state_change(dev);
+	}
+
+	return 0;
+}
+
+static size_t ip6gre_get_size(const struct net_device *dev)
+{
+	return
+		/* IFLA_GRE_LINK */
+		nla_total_size(4) +
+		/* IFLA_GRE_IFLAGS */
+		nla_total_size(2) +
+		/* IFLA_GRE_OFLAGS */
+		nla_total_size(2) +
+		/* IFLA_GRE_IKEY */
+		nla_total_size(4) +
+		/* IFLA_GRE_OKEY */
+		nla_total_size(4) +
+		/* IFLA_GRE_LOCAL */
+		nla_total_size(4) +
+		/* IFLA_GRE_REMOTE */
+		nla_total_size(4) +
+		/* IFLA_GRE_TTL */
+		nla_total_size(1) +
+		/* IFLA_GRE_TOS */
+		nla_total_size(1) +
+		/* IFLA_GRE_ENCAP_LIMIT */
+		nla_total_size(1) +
+		/* IFLA_GRE_FLOWINFO */
+		nla_total_size(4) +
+		/* IFLA_GRE_FLAGS */
+		nla_total_size(4) +
+		0;
+}
+
+static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device 
*dev)
+{
+	struct ip6_tnl *t = netdev_priv(dev);
+	struct __ip6_tnl_parm *p = &t->parms;
+
+	if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
+	    nla_put_be16(skb, IFLA_GRE_IFLAGS, p->i_flags) ||
+	    nla_put_be16(skb, IFLA_GRE_OFLAGS, p->o_flags) ||
+	    nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
+	    nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
+	    nla_put(skb, IFLA_GRE_LOCAL, sizeof(struct in6_addr), &p->raddr) 
||
+	    nla_put(skb, IFLA_GRE_REMOTE, sizeof(struct in6_addr), &p->laddr) 
||
+	    nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
+	    /*nla_put_u8(skb, IFLA_GRE_TOS, t->priority) ||*/
+	    nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
+	    nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
+	    nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags))
+		goto nla_put_failure;
+	return 0;
+
+nla_put_failure:
+	return -EMSGSIZE;
+}
+
+static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
+	[IFLA_GRE_LINK]        = { .type = NLA_U32 },
+	[IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
+	[IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
+	[IFLA_GRE_IKEY]        = { .type = NLA_U32 },
+	[IFLA_GRE_OKEY]        = { .type = NLA_U32 },
+	[IFLA_GRE_LOCAL]       = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) 
},
+	[IFLA_GRE_REMOTE]      = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) 
},
+	[IFLA_GRE_TTL]         = { .type = NLA_U8 },
+	[IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
+	[IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
+	[IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
+};
+
+static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
+	.kind		= "ip6gre",
+	.maxtype	= IFLA_GRE_MAX,
+	.policy		= ip6gre_policy,
+	.priv_size	= sizeof(struct ip6_tnl),
+	.setup		= ip6gre_tunnel_setup,
+	.validate	= ip6gre_tunnel_validate,
+	.newlink	= ip6gre_newlink,
+	.changelink	= ip6gre_changelink,
+	.get_size	= ip6gre_get_size,
+	.fill_info	= ip6gre_fill_info,
+};
+
+static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
+	.kind		= "ip6gretap",
+	.maxtype	= IFLA_GRE_MAX,
+	.policy		= ip6gre_policy,
+	.priv_size	= sizeof(struct ip6_tnl),
+	.setup		= ip6gre_tap_setup,
+	.validate	= ip6gre_tap_validate,
+	.newlink	= ip6gre_newlink,
+	.changelink	= ip6gre_changelink,
+	.get_size	= ip6gre_get_size,
+	.fill_info	= ip6gre_fill_info,
+};
+
+/*
+ *	And now the modules code and kernel interface.
+ */
+
+static int __init ip6gre_init(void)
+{
+	int err;
+
+	pr_info("GRE over IPv6 tunneling driver\n");
+
+	err = register_pernet_device(&ip6gre_net_ops);
+	if (err < 0)
+		return err;
+
+	err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
+	if (err < 0) {
+		pr_info("%s: can't add protocol\n", __func__);
+		goto add_proto_failed;
+	}
+
+	err = rtnl_link_register(&ip6gre_link_ops);
+	if (err < 0)
+		goto rtnl_link_failed;
+
+	err = rtnl_link_register(&ip6gre_tap_ops);
+	if (err < 0)
+		goto tap_ops_failed;
+
+out:
+	return err;
+
+tap_ops_failed:
+	rtnl_link_unregister(&ip6gre_link_ops);
+rtnl_link_failed:
+	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
+add_proto_failed:
+	unregister_pernet_device(&ip6gre_net_ops);
+	goto out;
+}
+
+static void __exit ip6gre_fini(void)
+{
+	rtnl_link_unregister(&ip6gre_tap_ops);
+	rtnl_link_unregister(&ip6gre_link_ops);
+	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
+	unregister_pernet_device(&ip6gre_net_ops);
+}
+
+module_init(ip6gre_init);
+module_exit(ip6gre_fini);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
+MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
+MODULE_ALIAS_RTNL_LINK("ip6gre");
+MODULE_ALIAS_NETDEV("ip6gre0");
+
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 9a1d5fe..33d2a0e 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -126,7 +126,7 @@  static struct net_device_stats *ip6_get_stats(struct 
net_device *dev)
  * Locking : hash tables are protected by RCU and RTNL
  */
 
-static inline struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t)
+struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t)
 {
 	struct dst_entry *dst = t->dst_cache;