gre: Support GRE over IPv6
authorxeb@mail.ru <xeb@mail.ru>
Fri, 10 Aug 2012 00:51:50 +0000 (00:51 +0000)
committerDavid S. Miller <davem@davemloft.net>
Tue, 14 Aug 2012 21:28:32 +0000 (14:28 -0700)
GRE over IPv6 implementation.

Signed-off-by: Dmitry Kozlov <xeb@mail.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
include/linux/if_arp.h
include/linux/if_tunnel.h
include/linux/ip6_tunnel.h
include/net/ip6_tunnel.h
include/net/ipv6.h
net/ipv6/Kconfig
net/ipv6/Makefile
net/ipv6/ip6_gre.c [new file with mode: 0644]
net/ipv6/ip6_tunnel.c

index f0e69c6e82083c33eb799cbba0eb2ba789699a56..9adcc29f084af485a8b674dd6c6b3b51532ce68b 100644 (file)
@@ -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 */
index 5efff60b6f56906112b5c71dffbdf47b2b22cc8d..8c5035ac31421aa1bee89a34c342de34ff63131a 100644 (file)
@@ -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,
 };
 
index bf22b03179022da13565642026213601e879fa88..48af63c9a48d25f5f6d9e2681e6eeeec5a4fef8c 100644 (file)
@@ -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
index 358fb86f57eb952816bc76736b7b85644dd77184..e03047f7090bb3419c2aa6f8b39f3a7ff0494f8a 100644 (file)
@@ -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 */
 /* 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
index 01c34b363a34d1f7b126d55dffd8e170963528ed..6d01fb00ff2b613f7061f16e91c6890b2c927e61 100644 (file)
@@ -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. */
index 5728695b54492dc2d275458b8db786f410e94002..4f7fe7270e3703226de121041d1e5e96a5b127df 100644 (file)
@@ -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
index 686934acfac18eac215a17b8d4d01ea5ad03c860..b6d3f79151e28251f3b3b5a062869fa9acb64526 100644 (file)
@@ -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 (file)
index 0000000..a84ad5d
--- /dev/null
@@ -0,0 +1,1790 @@
+/*
+ *     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");
index 9a1d5fe6aef8f229e22c8b2e8f3cef1663be09ce..33d2a0e6712de084077727298d9e2353f39eb9c0 100644 (file)
@@ -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;
 
@@ -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)