/*
   * INET		An implementation of the TCP/IP protocol suite for the LINUX
   *		operating system.  INET is implemented using the  BSD Socket
   *		interface as the means of communication with the user level.
   *
   *		Routing netlink socket interface: protocol independent part.
   *
   * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.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.
   *
   *	Fixes:
   *	Vitaly E. Lavrov		RTA_OK arithmetics was wrong.
   */

  #include <linux/errno.h>
  #include <linux/module.h>
  #include <linux/types.h>
  #include <linux/socket.h>
  #include <linux/kernel.h>

  #include <linux/timer.h>
  #include <linux/string.h>
  #include <linux/sockios.h>
  #include <linux/net.h>
  #include <linux/fcntl.h>
  #include <linux/mm.h>
  #include <linux/slab.h>
  #include <linux/interrupt.h>
  #include <linux/capability.h>
  #include <linux/skbuff.h>
  #include <linux/init.h>
  #include <linux/security.h>

  #include <linux/mutex.h>

  #include <linux/if_addr.h>

  #include <linux/nsproxy.h>

  
  #include <asm/uaccess.h>
  #include <asm/system.h>
  #include <asm/string.h>
  
  #include <linux/inet.h>
  #include <linux/netdevice.h>
  #include <net/ip.h>
  #include <net/protocol.h>
  #include <net/arp.h>
  #include <net/route.h>
  #include <net/udp.h>
  #include <net/sock.h>
  #include <net/pkt_sched.h>

  #include <net/fib_rules.h>

  #include <net/rtnetlink.h>

  struct rtnl_link
  {
  	rtnl_doit_func		doit;
  	rtnl_dumpit_func	dumpit;
  };

  static DEFINE_MUTEX(rtnl_mutex);

  
  void rtnl_lock(void)
  {

  	mutex_lock(&rtnl_mutex);

  }

  void __rtnl_unlock(void)

  {

  	mutex_unlock(&rtnl_mutex);

  }

  void rtnl_unlock(void)
  {

  	/* This fellow will unlock it for us. */

  	netdev_run_todo();
  }

  int rtnl_trylock(void)
  {
  	return mutex_trylock(&rtnl_mutex);
  }

  int rtnl_is_locked(void)
  {
  	return mutex_is_locked(&rtnl_mutex);
  }

  static struct rtnl_link *rtnl_msg_handlers[NPROTO];

  
  static inline int rtm_msgindex(int msgtype)
  {
  	int msgindex = msgtype - RTM_BASE;
  
  	/*
  	 * msgindex < 0 implies someone tried to register a netlink
  	 * control code. msgindex >= RTM_NR_MSGTYPES may indicate that
  	 * the message type has not been added to linux/rtnetlink.h
  	 */
  	BUG_ON(msgindex < 0 || msgindex >= RTM_NR_MSGTYPES);
  
  	return msgindex;
  }
  
  static rtnl_doit_func rtnl_get_doit(int protocol, int msgindex)
  {
  	struct rtnl_link *tab;
  
  	tab = rtnl_msg_handlers[protocol];

  	if (tab == NULL || tab[msgindex].doit == NULL)

  		tab = rtnl_msg_handlers[PF_UNSPEC];

  	return tab ? tab[msgindex].doit : NULL;

  }
  
  static rtnl_dumpit_func rtnl_get_dumpit(int protocol, int msgindex)
  {
  	struct rtnl_link *tab;
  
  	tab = rtnl_msg_handlers[protocol];

  	if (tab == NULL || tab[msgindex].dumpit == NULL)

  		tab = rtnl_msg_handlers[PF_UNSPEC];

  	return tab ? tab[msgindex].dumpit : NULL;

  }
  
  /**
   * __rtnl_register - Register a rtnetlink message type
   * @protocol: Protocol family or PF_UNSPEC
   * @msgtype: rtnetlink message type
   * @doit: Function pointer called for each request message
   * @dumpit: Function pointer called for each dump request (NLM_F_DUMP) message
   *
   * Registers the specified function pointers (at least one of them has
   * to be non-NULL) to be called whenever a request message for the
   * specified protocol family and message type is received.
   *
   * The special protocol family PF_UNSPEC may be used to define fallback
   * function pointers for the case when no entry for the specific protocol
   * family exists.
   *
   * Returns 0 on success or a negative error code.
   */
  int __rtnl_register(int protocol, int msgtype,
  		    rtnl_doit_func doit, rtnl_dumpit_func dumpit)
  {
  	struct rtnl_link *tab;
  	int msgindex;
  
  	BUG_ON(protocol < 0 || protocol >= NPROTO);
  	msgindex = rtm_msgindex(msgtype);
  
  	tab = rtnl_msg_handlers[protocol];
  	if (tab == NULL) {
  		tab = kcalloc(RTM_NR_MSGTYPES, sizeof(*tab), GFP_KERNEL);
  		if (tab == NULL)
  			return -ENOBUFS;
  
  		rtnl_msg_handlers[protocol] = tab;
  	}
  
  	if (doit)
  		tab[msgindex].doit = doit;
  
  	if (dumpit)
  		tab[msgindex].dumpit = dumpit;
  
  	return 0;
  }
  
  EXPORT_SYMBOL_GPL(__rtnl_register);
  
  /**
   * rtnl_register - Register a rtnetlink message type
   *
   * Identical to __rtnl_register() but panics on failure. This is useful
   * as failure of this function is very unlikely, it can only happen due
   * to lack of memory when allocating the chain to store all message
   * handlers for a protocol. Meant for use in init functions where lack
   * of memory implies no sense in continueing.
   */
  void rtnl_register(int protocol, int msgtype,
  		   rtnl_doit_func doit, rtnl_dumpit_func dumpit)
  {
  	if (__rtnl_register(protocol, msgtype, doit, dumpit) < 0)
  		panic("Unable to register rtnetlink message handler, "
  		      "protocol = %d, message type = %d
  ",
  		      protocol, msgtype);
  }
  
  EXPORT_SYMBOL_GPL(rtnl_register);
  
  /**
   * rtnl_unregister - Unregister a rtnetlink message type
   * @protocol: Protocol family or PF_UNSPEC
   * @msgtype: rtnetlink message type
   *
   * Returns 0 on success or a negative error code.
   */
  int rtnl_unregister(int protocol, int msgtype)
  {
  	int msgindex;
  
  	BUG_ON(protocol < 0 || protocol >= NPROTO);
  	msgindex = rtm_msgindex(msgtype);
  
  	if (rtnl_msg_handlers[protocol] == NULL)
  		return -ENOENT;
  
  	rtnl_msg_handlers[protocol][msgindex].doit = NULL;
  	rtnl_msg_handlers[protocol][msgindex].dumpit = NULL;
  
  	return 0;
  }
  
  EXPORT_SYMBOL_GPL(rtnl_unregister);
  
  /**
   * rtnl_unregister_all - Unregister all rtnetlink message type of a protocol
   * @protocol : Protocol family or PF_UNSPEC
   *
   * Identical to calling rtnl_unregster() for all registered message types
   * of a certain protocol family.
   */
  void rtnl_unregister_all(int protocol)
  {
  	BUG_ON(protocol < 0 || protocol >= NPROTO);
  
  	kfree(rtnl_msg_handlers[protocol]);
  	rtnl_msg_handlers[protocol] = NULL;
  }
  
  EXPORT_SYMBOL_GPL(rtnl_unregister_all);

  static LIST_HEAD(link_ops);
  
  /**
   * __rtnl_link_register - Register rtnl_link_ops with rtnetlink.
   * @ops: struct rtnl_link_ops * to register
   *
   * The caller must hold the rtnl_mutex. This function should be used
   * by drivers that create devices during module initialization. It
   * must be called before registering the devices.
   *
   * Returns 0 on success or a negative error code.
   */
  int __rtnl_link_register(struct rtnl_link_ops *ops)
  {

  	if (!ops->dellink)
  		ops->dellink = unregister_netdevice;

  	list_add_tail(&ops->list, &link_ops);
  	return 0;
  }
  
  EXPORT_SYMBOL_GPL(__rtnl_link_register);
  
  /**
   * rtnl_link_register - Register rtnl_link_ops with rtnetlink.
   * @ops: struct rtnl_link_ops * to register
   *
   * Returns 0 on success or a negative error code.
   */
  int rtnl_link_register(struct rtnl_link_ops *ops)
  {
  	int err;
  
  	rtnl_lock();
  	err = __rtnl_link_register(ops);
  	rtnl_unlock();
  	return err;
  }
  
  EXPORT_SYMBOL_GPL(rtnl_link_register);

  static void __rtnl_kill_links(struct net *net, struct rtnl_link_ops *ops)
  {
  	struct net_device *dev;
  restart:
  	for_each_netdev(net, dev) {
  		if (dev->rtnl_link_ops == ops) {
  			ops->dellink(dev);
  			goto restart;
  		}
  	}
  }
  
  void rtnl_kill_links(struct net *net, struct rtnl_link_ops *ops)
  {
  	rtnl_lock();
  	__rtnl_kill_links(net, ops);
  	rtnl_unlock();
  }
  EXPORT_SYMBOL_GPL(rtnl_kill_links);

  /**
   * __rtnl_link_unregister - Unregister rtnl_link_ops from rtnetlink.
   * @ops: struct rtnl_link_ops * to unregister
   *

   * The caller must hold the rtnl_mutex.

   */
  void __rtnl_link_unregister(struct rtnl_link_ops *ops)
  {

  	struct net *net;

  	for_each_net(net) {

  		__rtnl_kill_links(net, ops);

  	}

  	list_del(&ops->list);
  }
  
  EXPORT_SYMBOL_GPL(__rtnl_link_unregister);
  
  /**
   * rtnl_link_unregister - Unregister rtnl_link_ops from rtnetlink.
   * @ops: struct rtnl_link_ops * to unregister
   */
  void rtnl_link_unregister(struct rtnl_link_ops *ops)
  {
  	rtnl_lock();
  	__rtnl_link_unregister(ops);
  	rtnl_unlock();
  }
  
  EXPORT_SYMBOL_GPL(rtnl_link_unregister);
  
  static const struct rtnl_link_ops *rtnl_link_ops_get(const char *kind)
  {
  	const struct rtnl_link_ops *ops;
  
  	list_for_each_entry(ops, &link_ops, list) {
  		if (!strcmp(ops->kind, kind))
  			return ops;
  	}
  	return NULL;
  }
  
  static size_t rtnl_link_get_size(const struct net_device *dev)
  {
  	const struct rtnl_link_ops *ops = dev->rtnl_link_ops;
  	size_t size;
  
  	if (!ops)
  		return 0;
  
  	size = nlmsg_total_size(sizeof(struct nlattr)) + /* IFLA_LINKINFO */
  	       nlmsg_total_size(strlen(ops->kind) + 1);	 /* IFLA_INFO_KIND */
  
  	if (ops->get_size)
  		/* IFLA_INFO_DATA + nested data */
  		size += nlmsg_total_size(sizeof(struct nlattr)) +
  			ops->get_size(dev);
  
  	if (ops->get_xstats_size)
  		size += ops->get_xstats_size(dev);	/* IFLA_INFO_XSTATS */
  
  	return size;
  }
  
  static int rtnl_link_fill(struct sk_buff *skb, const struct net_device *dev)
  {
  	const struct rtnl_link_ops *ops = dev->rtnl_link_ops;
  	struct nlattr *linkinfo, *data;
  	int err = -EMSGSIZE;
  
  	linkinfo = nla_nest_start(skb, IFLA_LINKINFO);
  	if (linkinfo == NULL)
  		goto out;
  
  	if (nla_put_string(skb, IFLA_INFO_KIND, ops->kind) < 0)
  		goto err_cancel_link;
  	if (ops->fill_xstats) {
  		err = ops->fill_xstats(skb, dev);
  		if (err < 0)
  			goto err_cancel_link;
  	}
  	if (ops->fill_info) {
  		data = nla_nest_start(skb, IFLA_INFO_DATA);
  		if (data == NULL)
  			goto err_cancel_link;
  		err = ops->fill_info(skb, dev);
  		if (err < 0)
  			goto err_cancel_data;
  		nla_nest_end(skb, data);
  	}
  
  	nla_nest_end(skb, linkinfo);
  	return 0;
  
  err_cancel_data:
  	nla_nest_cancel(skb, data);
  err_cancel_link:
  	nla_nest_cancel(skb, linkinfo);
  out:
  	return err;
  }

  static const int rtm_min[RTM_NR_FAMILIES] =

  {

  	[RTM_FAM(RTM_NEWLINK)]      = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
  	[RTM_FAM(RTM_NEWADDR)]      = NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
  	[RTM_FAM(RTM_NEWROUTE)]     = NLMSG_LENGTH(sizeof(struct rtmsg)),

  	[RTM_FAM(RTM_NEWRULE)]      = NLMSG_LENGTH(sizeof(struct fib_rule_hdr)),

  	[RTM_FAM(RTM_NEWQDISC)]     = NLMSG_LENGTH(sizeof(struct tcmsg)),
  	[RTM_FAM(RTM_NEWTCLASS)]    = NLMSG_LENGTH(sizeof(struct tcmsg)),
  	[RTM_FAM(RTM_NEWTFILTER)]   = NLMSG_LENGTH(sizeof(struct tcmsg)),
  	[RTM_FAM(RTM_NEWACTION)]    = NLMSG_LENGTH(sizeof(struct tcamsg)),

  	[RTM_FAM(RTM_GETMULTICAST)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
  	[RTM_FAM(RTM_GETANYCAST)]   = NLMSG_LENGTH(sizeof(struct rtgenmsg)),

  };

  static const int rta_max[RTM_NR_FAMILIES] =

  {

  	[RTM_FAM(RTM_NEWLINK)]      = IFLA_MAX,
  	[RTM_FAM(RTM_NEWADDR)]      = IFA_MAX,
  	[RTM_FAM(RTM_NEWROUTE)]     = RTA_MAX,

  	[RTM_FAM(RTM_NEWRULE)]      = FRA_MAX,

  	[RTM_FAM(RTM_NEWQDISC)]     = TCA_MAX,
  	[RTM_FAM(RTM_NEWTCLASS)]    = TCA_MAX,
  	[RTM_FAM(RTM_NEWTFILTER)]   = TCA_MAX,
  	[RTM_FAM(RTM_NEWACTION)]    = TCAA_MAX,

  };
  
  void __rta_fill(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
  {
  	struct rtattr *rta;
  	int size = RTA_LENGTH(attrlen);
  
  	rta = (struct rtattr*)skb_put(skb, RTA_ALIGN(size));
  	rta->rta_type = attrtype;
  	rta->rta_len = size;
  	memcpy(RTA_DATA(rta), data, attrlen);

  	memset(RTA_DATA(rta) + attrlen, 0, RTA_ALIGN(size) - size);

  }

  int rtnetlink_send(struct sk_buff *skb, struct net *net, u32 pid, unsigned group, int echo)

  {

  	struct sock *rtnl = net->rtnl;

  	int err = 0;

  	NETLINK_CB(skb).dst_group = group;

  	if (echo)
  		atomic_inc(&skb->users);
  	netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL);
  	if (echo)
  		err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
  	return err;
  }

  int rtnl_unicast(struct sk_buff *skb, struct net *net, u32 pid)

  {

  	struct sock *rtnl = net->rtnl;

  	return nlmsg_unicast(rtnl, skb, pid);
  }

  void rtnl_notify(struct sk_buff *skb, struct net *net, u32 pid, u32 group,
  		 struct nlmsghdr *nlh, gfp_t flags)

  {

  	struct sock *rtnl = net->rtnl;

  	int report = 0;
  
  	if (nlh)
  		report = nlmsg_report(nlh);

  	nlmsg_notify(rtnl, skb, pid, group, report, flags);

  }

  void rtnl_set_sk_err(struct net *net, u32 group, int error)

  {

  	struct sock *rtnl = net->rtnl;

  	netlink_set_err(rtnl, 0, group, error);
  }

  int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics)
  {

  	struct nlattr *mx;
  	int i, valid = 0;
  
  	mx = nla_nest_start(skb, RTA_METRICS);
  	if (mx == NULL)
  		return -ENOBUFS;
  
  	for (i = 0; i < RTAX_MAX; i++) {
  		if (metrics[i]) {
  			valid++;
  			NLA_PUT_U32(skb, i+1, metrics[i]);
  		}

  	}

  	if (!valid) {
  		nla_nest_cancel(skb, mx);
  		return 0;
  	}

  
  	return nla_nest_end(skb, mx);
  
  nla_put_failure:

  	nla_nest_cancel(skb, mx);
  	return -EMSGSIZE;

  }

  int rtnl_put_cacheinfo(struct sk_buff *skb, struct dst_entry *dst, u32 id,
  		       u32 ts, u32 tsage, long expires, u32 error)
  {
  	struct rta_cacheinfo ci = {
  		.rta_lastuse = jiffies_to_clock_t(jiffies - dst->lastuse),
  		.rta_used = dst->__use,
  		.rta_clntref = atomic_read(&(dst->__refcnt)),
  		.rta_error = error,
  		.rta_id =  id,
  		.rta_ts = ts,
  		.rta_tsage = tsage,
  	};
  
  	if (expires)
  		ci.rta_expires = jiffies_to_clock_t(expires);
  
  	return nla_put(skb, RTA_CACHEINFO, sizeof(ci), &ci);
  }
  
  EXPORT_SYMBOL_GPL(rtnl_put_cacheinfo);

  static void set_operstate(struct net_device *dev, unsigned char transition)

  {
  	unsigned char operstate = dev->operstate;
  
  	switch(transition) {
  	case IF_OPER_UP:
  		if ((operstate == IF_OPER_DORMANT ||
  		     operstate == IF_OPER_UNKNOWN) &&
  		    !netif_dormant(dev))
  			operstate = IF_OPER_UP;
  		break;
  
  	case IF_OPER_DORMANT:
  		if (operstate == IF_OPER_UP ||
  		    operstate == IF_OPER_UNKNOWN)
  			operstate = IF_OPER_DORMANT;
  		break;

  	}

  
  	if (dev->operstate != operstate) {
  		write_lock_bh(&dev_base_lock);
  		dev->operstate = operstate;
  		write_unlock_bh(&dev_base_lock);

  		netdev_state_change(dev);
  	}

  }

  static void copy_rtnl_link_stats(struct rtnl_link_stats *a,

  				 const struct net_device_stats *b)

  {

  	a->rx_packets = b->rx_packets;
  	a->tx_packets = b->tx_packets;
  	a->rx_bytes = b->rx_bytes;
  	a->tx_bytes = b->tx_bytes;
  	a->rx_errors = b->rx_errors;
  	a->tx_errors = b->tx_errors;
  	a->rx_dropped = b->rx_dropped;
  	a->tx_dropped = b->tx_dropped;
  
  	a->multicast = b->multicast;
  	a->collisions = b->collisions;
  
  	a->rx_length_errors = b->rx_length_errors;
  	a->rx_over_errors = b->rx_over_errors;
  	a->rx_crc_errors = b->rx_crc_errors;
  	a->rx_frame_errors = b->rx_frame_errors;
  	a->rx_fifo_errors = b->rx_fifo_errors;
  	a->rx_missed_errors = b->rx_missed_errors;
  
  	a->tx_aborted_errors = b->tx_aborted_errors;
  	a->tx_carrier_errors = b->tx_carrier_errors;
  	a->tx_fifo_errors = b->tx_fifo_errors;
  	a->tx_heartbeat_errors = b->tx_heartbeat_errors;
  	a->tx_window_errors = b->tx_window_errors;
  
  	a->rx_compressed = b->rx_compressed;
  	a->tx_compressed = b->tx_compressed;
  };

  static inline size_t if_nlmsg_size(const struct net_device *dev)

  {
  	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
  	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */

  	       + nla_total_size(IFALIASZ) /* IFLA_IFALIAS */

  	       + nla_total_size(IFNAMSIZ) /* IFLA_QDISC */
  	       + nla_total_size(sizeof(struct rtnl_link_ifmap))
  	       + nla_total_size(sizeof(struct rtnl_link_stats))
  	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
  	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_BROADCAST */
  	       + nla_total_size(4) /* IFLA_TXQLEN */
  	       + nla_total_size(4) /* IFLA_WEIGHT */
  	       + nla_total_size(4) /* IFLA_MTU */
  	       + nla_total_size(4) /* IFLA_LINK */
  	       + nla_total_size(4) /* IFLA_MASTER */
  	       + nla_total_size(1) /* IFLA_OPERSTATE */

  	       + nla_total_size(1) /* IFLA_LINKMODE */
  	       + rtnl_link_get_size(dev); /* IFLA_LINKINFO */

  }

  static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,

  			    int type, u32 pid, u32 seq, u32 change,
  			    unsigned int flags)

  {

  	struct netdev_queue *txq;

  	struct ifinfomsg *ifm;
  	struct nlmsghdr *nlh;

  	const struct net_device_stats *stats;

  	struct nlattr *attr;

  	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ifm), flags);
  	if (nlh == NULL)

  		return -EMSGSIZE;

  	ifm = nlmsg_data(nlh);
  	ifm->ifi_family = AF_UNSPEC;
  	ifm->__ifi_pad = 0;
  	ifm->ifi_type = dev->type;
  	ifm->ifi_index = dev->ifindex;
  	ifm->ifi_flags = dev_get_flags(dev);
  	ifm->ifi_change = change;
  
  	NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name);
  	NLA_PUT_U32(skb, IFLA_TXQLEN, dev->tx_queue_len);

  	NLA_PUT_U8(skb, IFLA_OPERSTATE,
  		   netif_running(dev) ? dev->operstate : IF_OPER_DOWN);
  	NLA_PUT_U8(skb, IFLA_LINKMODE, dev->link_mode);
  	NLA_PUT_U32(skb, IFLA_MTU, dev->mtu);
  
  	if (dev->ifindex != dev->iflink)
  		NLA_PUT_U32(skb, IFLA_LINK, dev->iflink);
  
  	if (dev->master)
  		NLA_PUT_U32(skb, IFLA_MASTER, dev->master->ifindex);

  	txq = netdev_get_tx_queue(dev, 0);

  	if (txq->qdisc_sleeping)
  		NLA_PUT_STRING(skb, IFLA_QDISC, txq->qdisc_sleeping->ops->id);

  	if (dev->ifalias)
  		NLA_PUT_STRING(skb, IFLA_IFALIAS, dev->ifalias);

  	if (1) {

  		struct rtnl_link_ifmap map = {
  			.mem_start   = dev->mem_start,
  			.mem_end     = dev->mem_end,
  			.base_addr   = dev->base_addr,
  			.irq         = dev->irq,
  			.dma         = dev->dma,
  			.port        = dev->if_port,
  		};

  		NLA_PUT(skb, IFLA_MAP, sizeof(map), &map);

  	}
  
  	if (dev->addr_len) {

  		NLA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
  		NLA_PUT(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast);

  	}

  	attr = nla_reserve(skb, IFLA_STATS,
  			sizeof(struct rtnl_link_stats));
  	if (attr == NULL)
  		goto nla_put_failure;

  	stats = dev_get_stats(dev);

  	copy_rtnl_link_stats(nla_data(attr), stats);

  	if (dev->rtnl_link_ops) {
  		if (rtnl_link_fill(skb, dev) < 0)
  			goto nla_put_failure;
  	}

  	return nlmsg_end(skb, nlh);
  
  nla_put_failure:

  	nlmsg_cancel(skb, nlh);
  	return -EMSGSIZE;

  }

  static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)

  {

  	struct net *net = sock_net(skb->sk);

  	int idx;
  	int s_idx = cb->args[0];
  	struct net_device *dev;

  	idx = 0;

  	for_each_netdev(net, dev) {

  		if (idx < s_idx)

  			goto cont;

  		if (rtnl_fill_ifinfo(skb, dev, RTM_NEWLINK,

  				     NETLINK_CB(cb->skb).pid,
  				     cb->nlh->nlmsg_seq, 0, NLM_F_MULTI) <= 0)

  			break;

  cont:
  		idx++;

  	}

  	cb->args[0] = idx;
  
  	return skb->len;
  }

  const struct nla_policy ifla_policy[IFLA_MAX+1] = {

  	[IFLA_IFNAME]		= { .type = NLA_STRING, .len = IFNAMSIZ-1 },

  	[IFLA_ADDRESS]		= { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
  	[IFLA_BROADCAST]	= { .type = NLA_BINARY, .len = MAX_ADDR_LEN },

  	[IFLA_MAP]		= { .len = sizeof(struct rtnl_link_ifmap) },

  	[IFLA_MTU]		= { .type = NLA_U32 },

  	[IFLA_LINK]		= { .type = NLA_U32 },

  	[IFLA_TXQLEN]		= { .type = NLA_U32 },
  	[IFLA_WEIGHT]		= { .type = NLA_U32 },
  	[IFLA_OPERSTATE]	= { .type = NLA_U8 },
  	[IFLA_LINKMODE]		= { .type = NLA_U8 },

  	[IFLA_LINKINFO]		= { .type = NLA_NESTED },

  	[IFLA_NET_NS_PID]	= { .type = NLA_U32 },

  	[IFLA_IFALIAS]	        = { .type = NLA_STRING, .len = IFALIASZ-1 },

  };

  static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {
  	[IFLA_INFO_KIND]	= { .type = NLA_STRING },
  	[IFLA_INFO_DATA]	= { .type = NLA_NESTED },
  };

  static struct net *get_net_ns_by_pid(pid_t pid)
  {
  	struct task_struct *tsk;
  	struct net *net;
  
  	/* Lookup the network namespace */
  	net = ERR_PTR(-ESRCH);
  	rcu_read_lock();

  	tsk = find_task_by_vpid(pid);

  	if (tsk) {

  		struct nsproxy *nsproxy;
  		nsproxy = task_nsproxy(tsk);
  		if (nsproxy)
  			net = get_net(nsproxy->net_ns);

  	}
  	rcu_read_unlock();
  	return net;
  }

  static int validate_linkmsg(struct net_device *dev, struct nlattr *tb[])
  {
  	if (dev) {
  		if (tb[IFLA_ADDRESS] &&
  		    nla_len(tb[IFLA_ADDRESS]) < dev->addr_len)
  			return -EINVAL;
  
  		if (tb[IFLA_BROADCAST] &&
  		    nla_len(tb[IFLA_BROADCAST]) < dev->addr_len)
  			return -EINVAL;
  	}
  
  	return 0;
  }

  static int do_setlink(struct net_device *dev, struct ifinfomsg *ifm,

  		      struct nlattr **tb, char *ifname, int modified)

  {

  	const struct net_device_ops *ops = dev->netdev_ops;

  	int send_addr_notify = 0;

  	int err;

  	if (tb[IFLA_NET_NS_PID]) {
  		struct net *net;
  		net = get_net_ns_by_pid(nla_get_u32(tb[IFLA_NET_NS_PID]));
  		if (IS_ERR(net)) {
  			err = PTR_ERR(net);
  			goto errout;
  		}
  		err = dev_change_net_namespace(dev, net, ifname);
  		put_net(net);
  		if (err)
  			goto errout;
  		modified = 1;
  	}

  	if (tb[IFLA_MAP]) {

  		struct rtnl_link_ifmap *u_map;
  		struct ifmap k_map;

  		if (!ops->ndo_set_config) {

  			err = -EOPNOTSUPP;

  			goto errout;

  		}
  
  		if (!netif_device_present(dev)) {
  			err = -ENODEV;

  			goto errout;

  		}

  		u_map = nla_data(tb[IFLA_MAP]);

  		k_map.mem_start = (unsigned long) u_map->mem_start;
  		k_map.mem_end = (unsigned long) u_map->mem_end;
  		k_map.base_addr = (unsigned short) u_map->base_addr;
  		k_map.irq = (unsigned char) u_map->irq;
  		k_map.dma = (unsigned char) u_map->dma;
  		k_map.port = (unsigned char) u_map->port;

  		err = ops->ndo_set_config(dev, &k_map);

  		if (err < 0)

  			goto errout;

  		modified = 1;

  	}

  	if (tb[IFLA_ADDRESS]) {

  		struct sockaddr *sa;
  		int len;

  		if (!ops->ndo_set_mac_address) {

  			err = -EOPNOTSUPP;

  			goto errout;

  		}

  		if (!netif_device_present(dev)) {
  			err = -ENODEV;

  			goto errout;

  		}

  		len = sizeof(sa_family_t) + dev->addr_len;
  		sa = kmalloc(len, GFP_KERNEL);
  		if (!sa) {
  			err = -ENOMEM;

  			goto errout;

  		}
  		sa->sa_family = dev->type;

  		memcpy(sa->sa_data, nla_data(tb[IFLA_ADDRESS]),

  		       dev->addr_len);

  		err = ops->ndo_set_mac_address(dev, sa);

  		kfree(sa);

  		if (err)

  			goto errout;

  		send_addr_notify = 1;

  		modified = 1;

  	}

  	if (tb[IFLA_MTU]) {
  		err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
  		if (err < 0)

  			goto errout;

  		modified = 1;

  	}

  	/*
  	 * Interface selected by interface index but interface
  	 * name provided implies that a name change has been
  	 * requested.
  	 */

  	if (ifm->ifi_index > 0 && ifname[0]) {

  		err = dev_change_name(dev, ifname);
  		if (err < 0)

  			goto errout;

  		modified = 1;

  	}

  	if (tb[IFLA_IFALIAS]) {
  		err = dev_set_alias(dev, nla_data(tb[IFLA_IFALIAS]),
  				    nla_len(tb[IFLA_IFALIAS]));
  		if (err < 0)
  			goto errout;
  		modified = 1;
  	}

  	if (tb[IFLA_BROADCAST]) {
  		nla_memcpy(dev->broadcast, tb[IFLA_BROADCAST], dev->addr_len);
  		send_addr_notify = 1;

  	}

  	if (ifm->ifi_flags || ifm->ifi_change) {
  		unsigned int flags = ifm->ifi_flags;
  
  		/* bugwards compatibility: ifi_change == 0 is treated as ~0 */
  		if (ifm->ifi_change)
  			flags = (flags & ifm->ifi_change) |
  				(dev->flags & ~ifm->ifi_change);

  		err = dev_change_flags(dev, flags);
  		if (err < 0)
  			goto errout;

  	}

  	if (tb[IFLA_TXQLEN])
  		dev->tx_queue_len = nla_get_u32(tb[IFLA_TXQLEN]);

  	if (tb[IFLA_OPERSTATE])

  		set_operstate(dev, nla_get_u8(tb[IFLA_OPERSTATE]));

  	if (tb[IFLA_LINKMODE]) {

  		write_lock_bh(&dev_base_lock);
  		dev->link_mode = nla_get_u8(tb[IFLA_LINKMODE]);
  		write_unlock_bh(&dev_base_lock);

  	}

  	err = 0;

  errout:

  	if (err < 0 && modified && net_ratelimit())
  		printk(KERN_WARNING "A link change request failed with "
  		       "some changes comitted already. Interface %s may "
  		       "have been left with an inconsistent configuration, "
  		       "please check.
  ", dev->name);

  	if (send_addr_notify)
  		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);

  	return err;
  }

  static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
  {

  	struct net *net = sock_net(skb->sk);

  	struct ifinfomsg *ifm;
  	struct net_device *dev;
  	int err;
  	struct nlattr *tb[IFLA_MAX+1];
  	char ifname[IFNAMSIZ];
  
  	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
  	if (err < 0)
  		goto errout;
  
  	if (tb[IFLA_IFNAME])
  		nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
  	else
  		ifname[0] = '\0';
  
  	err = -EINVAL;
  	ifm = nlmsg_data(nlh);
  	if (ifm->ifi_index > 0)

  		dev = dev_get_by_index(net, ifm->ifi_index);

  	else if (tb[IFLA_IFNAME])

  		dev = dev_get_by_name(net, ifname);

  	else
  		goto errout;
  
  	if (dev == NULL) {
  		err = -ENODEV;
  		goto errout;
  	}

  	if ((err = validate_linkmsg(dev, tb)) < 0)

  		goto errout_dev;

  	err = do_setlink(dev, ifm, tb, ifname, 0);

  errout_dev:

  	dev_put(dev);

  errout:

  	return err;
  }

  static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
  {

  	struct net *net = sock_net(skb->sk);

  	const struct rtnl_link_ops *ops;
  	struct net_device *dev;
  	struct ifinfomsg *ifm;
  	char ifname[IFNAMSIZ];
  	struct nlattr *tb[IFLA_MAX+1];
  	int err;
  
  	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
  	if (err < 0)
  		return err;
  
  	if (tb[IFLA_IFNAME])
  		nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
  
  	ifm = nlmsg_data(nlh);
  	if (ifm->ifi_index > 0)

  		dev = __dev_get_by_index(net, ifm->ifi_index);

  	else if (tb[IFLA_IFNAME])

  		dev = __dev_get_by_name(net, ifname);

  	else
  		return -EINVAL;
  
  	if (!dev)
  		return -ENODEV;
  
  	ops = dev->rtnl_link_ops;
  	if (!ops)
  		return -EOPNOTSUPP;
  
  	ops->dellink(dev);
  	return 0;
  }

  struct net_device *rtnl_create_link(struct net *net, char *ifname,

  		const struct rtnl_link_ops *ops, struct nlattr *tb[])
  {
  	int err;
  	struct net_device *dev;
  
  	err = -ENOMEM;
  	dev = alloc_netdev(ops->priv_size, ifname, ops->setup);
  	if (!dev)
  		goto err;
  
  	if (strchr(dev->name, '%')) {
  		err = dev_alloc_name(dev, dev->name);
  		if (err < 0)
  			goto err_free;
  	}

  	dev_net_set(dev, net);

  	dev->rtnl_link_ops = ops;
  
  	if (tb[IFLA_MTU])
  		dev->mtu = nla_get_u32(tb[IFLA_MTU]);
  	if (tb[IFLA_ADDRESS])
  		memcpy(dev->dev_addr, nla_data(tb[IFLA_ADDRESS]),
  				nla_len(tb[IFLA_ADDRESS]));
  	if (tb[IFLA_BROADCAST])
  		memcpy(dev->broadcast, nla_data(tb[IFLA_BROADCAST]),
  				nla_len(tb[IFLA_BROADCAST]));
  	if (tb[IFLA_TXQLEN])
  		dev->tx_queue_len = nla_get_u32(tb[IFLA_TXQLEN]);
  	if (tb[IFLA_OPERSTATE])

  		set_operstate(dev, nla_get_u8(tb[IFLA_OPERSTATE]));

  	if (tb[IFLA_LINKMODE])
  		dev->link_mode = nla_get_u8(tb[IFLA_LINKMODE]);
  
  	return dev;
  
  err_free:
  	free_netdev(dev);
  err:
  	return ERR_PTR(err);
  }

  static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
  {

  	struct net *net = sock_net(skb->sk);

  	const struct rtnl_link_ops *ops;
  	struct net_device *dev;
  	struct ifinfomsg *ifm;
  	char kind[MODULE_NAME_LEN];
  	char ifname[IFNAMSIZ];
  	struct nlattr *tb[IFLA_MAX+1];
  	struct nlattr *linkinfo[IFLA_INFO_MAX+1];
  	int err;

  #ifdef CONFIG_MODULES

  replay:

  #endif

  	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
  	if (err < 0)
  		return err;
  
  	if (tb[IFLA_IFNAME])
  		nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
  	else
  		ifname[0] = '\0';
  
  	ifm = nlmsg_data(nlh);
  	if (ifm->ifi_index > 0)

  		dev = __dev_get_by_index(net, ifm->ifi_index);

  	else if (ifname[0])

  		dev = __dev_get_by_name(net, ifname);

  	else
  		dev = NULL;

  	if ((err = validate_linkmsg(dev, tb)) < 0)
  		return err;

  	if (tb[IFLA_LINKINFO]) {
  		err = nla_parse_nested(linkinfo, IFLA_INFO_MAX,
  				       tb[IFLA_LINKINFO], ifla_info_policy);
  		if (err < 0)
  			return err;
  	} else
  		memset(linkinfo, 0, sizeof(linkinfo));
  
  	if (linkinfo[IFLA_INFO_KIND]) {
  		nla_strlcpy(kind, linkinfo[IFLA_INFO_KIND], sizeof(kind));
  		ops = rtnl_link_ops_get(kind);
  	} else {
  		kind[0] = '\0';
  		ops = NULL;
  	}
  
  	if (1) {
  		struct nlattr *attr[ops ? ops->maxtype + 1 : 0], **data = NULL;
  
  		if (ops) {
  			if (ops->maxtype && linkinfo[IFLA_INFO_DATA]) {
  				err = nla_parse_nested(attr, ops->maxtype,
  						       linkinfo[IFLA_INFO_DATA],
  						       ops->policy);
  				if (err < 0)
  					return err;
  				data = attr;
  			}
  			if (ops->validate) {
  				err = ops->validate(tb, data);
  				if (err < 0)
  					return err;
  			}
  		}
  
  		if (dev) {
  			int modified = 0;
  
  			if (nlh->nlmsg_flags & NLM_F_EXCL)
  				return -EEXIST;
  			if (nlh->nlmsg_flags & NLM_F_REPLACE)
  				return -EOPNOTSUPP;
  
  			if (linkinfo[IFLA_INFO_DATA]) {
  				if (!ops || ops != dev->rtnl_link_ops ||
  				    !ops->changelink)
  					return -EOPNOTSUPP;
  
  				err = ops->changelink(dev, tb, data);
  				if (err < 0)
  					return err;
  				modified = 1;
  			}
  
  			return do_setlink(dev, ifm, tb, ifname, modified);
  		}
  
  		if (!(nlh->nlmsg_flags & NLM_F_CREATE))
  			return -ENODEV;
  
  		if (ifm->ifi_index || ifm->ifi_flags || ifm->ifi_change)
  			return -EOPNOTSUPP;

  		if (tb[IFLA_MAP] || tb[IFLA_MASTER] || tb[IFLA_PROTINFO])

  			return -EOPNOTSUPP;
  
  		if (!ops) {

  #ifdef CONFIG_MODULES

  			if (kind[0]) {
  				__rtnl_unlock();
  				request_module("rtnl-link-%s", kind);
  				rtnl_lock();
  				ops = rtnl_link_ops_get(kind);
  				if (ops)
  					goto replay;
  			}
  #endif
  			return -EOPNOTSUPP;
  		}
  
  		if (!ifname[0])
  			snprintf(ifname, IFNAMSIZ, "%s%%d", ops->kind);

  		dev = rtnl_create_link(net, ifname, ops, tb);

  
  		if (IS_ERR(dev))
  			err = PTR_ERR(dev);
  		else if (ops->newlink)

  			err = ops->newlink(dev, tb, data);
  		else
  			err = register_netdevice(dev);

  
  		if (err < 0 && !IS_ERR(dev))

  			free_netdev(dev);
  		return err;
  	}
  }

  static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)

  {

  	struct net *net = sock_net(skb->sk);

  	struct ifinfomsg *ifm;
  	struct nlattr *tb[IFLA_MAX+1];
  	struct net_device *dev = NULL;
  	struct sk_buff *nskb;

  	int err;

  	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
  	if (err < 0)

  		return err;

  
  	ifm = nlmsg_data(nlh);

  	if (ifm->ifi_index > 0) {

  		dev = dev_get_by_index(net, ifm->ifi_index);

  		if (dev == NULL)
  			return -ENODEV;
  	} else

  		return -EINVAL;

  	nskb = nlmsg_new(if_nlmsg_size(dev), GFP_KERNEL);

  	if (nskb == NULL) {
  		err = -ENOBUFS;
  		goto errout;
  	}

  	err = rtnl_fill_ifinfo(nskb, dev, RTM_NEWLINK, NETLINK_CB(skb).pid,
  			       nlh->nlmsg_seq, 0, 0);

  	if (err < 0) {
  		/* -EMSGSIZE implies BUG in if_nlmsg_size */
  		WARN_ON(err == -EMSGSIZE);
  		kfree_skb(nskb);
  		goto errout;
  	}

  	err = rtnl_unicast(nskb, net, NETLINK_CB(skb).pid);

  errout:

  	dev_put(dev);

  	return err;

  }

  static int rtnl_dump_all(struct sk_buff *skb, struct netlink_callback *cb)

  {
  	int idx;
  	int s_idx = cb->family;
  
  	if (s_idx == 0)
  		s_idx = 1;
  	for (idx=1; idx<NPROTO; idx++) {
  		int type = cb->nlh->nlmsg_type-RTM_BASE;
  		if (idx < s_idx || idx == PF_PACKET)
  			continue;

  		if (rtnl_msg_handlers[idx] == NULL ||
  		    rtnl_msg_handlers[idx][type].dumpit == NULL)

  			continue;
  		if (idx > s_idx)
  			memset(&cb->args[0], 0, sizeof(cb->args));

  		if (rtnl_msg_handlers[idx][type].dumpit(skb, cb))

  			break;
  	}
  	cb->family = idx;
  
  	return skb->len;
  }
  
  void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
  {

  	struct net *net = dev_net(dev);

  	struct sk_buff *skb;

  	int err = -ENOBUFS;

  	skb = nlmsg_new(if_nlmsg_size(dev), GFP_KERNEL);

  	if (skb == NULL)
  		goto errout;

  	err = rtnl_fill_ifinfo(skb, dev, type, 0, 0, change, 0);

  	if (err < 0) {
  		/* -EMSGSIZE implies BUG in if_nlmsg_size() */
  		WARN_ON(err == -EMSGSIZE);
  		kfree_skb(skb);
  		goto errout;
  	}

  	rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, GFP_KERNEL);
  	return;

  errout:
  	if (err < 0)

  		rtnl_set_sk_err(net, RTNLGRP_LINK, err);

  }

  /* Protected by RTNL sempahore.  */
  static struct rtattr **rta_buf;
  static int rtattr_max;
  
  /* Process one rtnetlink message. */

  static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)

  {

  	struct net *net = sock_net(skb->sk);

  	rtnl_doit_func doit;

  	int sz_idx, kind;
  	int min_len;
  	int family;
  	int type;

  	int err;

  	type = nlh->nlmsg_type;

  	if (type > RTM_MAX)

  		return -EOPNOTSUPP;

  
  	type -= RTM_BASE;
  
  	/* All the messages must have at least 1 byte length */
  	if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct rtgenmsg)))
  		return 0;
  
  	family = ((struct rtgenmsg*)NLMSG_DATA(nlh))->rtgen_family;

  	if (family >= NPROTO)
  		return -EAFNOSUPPORT;

  	sz_idx = type>>2;
  	kind = type&3;

  	if (kind != 2 && security_netlink_recv(skb, CAP_NET_ADMIN))
  		return -EPERM;

  
  	if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {

  		struct sock *rtnl;

  		rtnl_dumpit_func dumpit;

  		dumpit = rtnl_get_dumpit(family, type);
  		if (dumpit == NULL)

  			return -EOPNOTSUPP;

  		__rtnl_unlock();

  		rtnl = net->rtnl;

  		err = netlink_dump_start(rtnl, skb, nlh, dumpit, NULL);
  		rtnl_lock();
  		return err;

  	}
  
  	memset(rta_buf, 0, (rtattr_max * sizeof(struct rtattr *)));
  
  	min_len = rtm_min[sz_idx];
  	if (nlh->nlmsg_len < min_len)

  		return -EINVAL;

  
  	if (nlh->nlmsg_len > min_len) {
  		int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
  		struct rtattr *attr = (void*)nlh + NLMSG_ALIGN(min_len);
  
  		while (RTA_OK(attr, attrlen)) {
  			unsigned flavor = attr->rta_type;
  			if (flavor) {
  				if (flavor > rta_max[sz_idx])

  					return -EINVAL;

  				rta_buf[flavor-1] = attr;
  			}
  			attr = RTA_NEXT(attr, attrlen);
  		}
  	}

  	doit = rtnl_get_doit(family, type);
  	if (doit == NULL)

  		return -EOPNOTSUPP;

  	return doit(skb, nlh, (void *)&rta_buf[0]);

  }

  static void rtnetlink_rcv(struct sk_buff *skb)

  {

  	rtnl_lock();
  	netlink_rcv_skb(skb, &rtnetlink_rcv_msg);
  	rtnl_unlock();

  }

  static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr)
  {
  	struct net_device *dev = ptr;

  	switch (event) {
  	case NETDEV_UNREGISTER:
  		rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
  		break;
  	case NETDEV_REGISTER:
  		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
  		break;
  	case NETDEV_UP:
  	case NETDEV_DOWN:
  		rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
  		break;
  	case NETDEV_CHANGE:
  	case NETDEV_GOING_DOWN:
  		break;
  	default:
  		rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
  		break;
  	}
  	return NOTIFY_DONE;
  }
  
  static struct notifier_block rtnetlink_dev_notifier = {
  	.notifier_call	= rtnetlink_event,
  };

  
  static int rtnetlink_net_init(struct net *net)
  {
  	struct sock *sk;
  	sk = netlink_kernel_create(net, NETLINK_ROUTE, RTNLGRP_MAX,
  				   rtnetlink_rcv, &rtnl_mutex, THIS_MODULE);
  	if (!sk)
  		return -ENOMEM;

  	net->rtnl = sk;
  	return 0;
  }
  
  static void rtnetlink_net_exit(struct net *net)
  {

  	netlink_kernel_release(net->rtnl);
  	net->rtnl = NULL;

  }
  
  static struct pernet_operations rtnetlink_net_ops = {
  	.init = rtnetlink_net_init,
  	.exit = rtnetlink_net_exit,
  };

  void __init rtnetlink_init(void)
  {
  	int i;
  
  	rtattr_max = 0;
  	for (i = 0; i < ARRAY_SIZE(rta_max); i++)
  		if (rta_max[i] > rtattr_max)
  			rtattr_max = rta_max[i];
  	rta_buf = kmalloc(rtattr_max * sizeof(struct rtattr *), GFP_KERNEL);
  	if (!rta_buf)
  		panic("rtnetlink_init: cannot allocate rta_buf
  ");

  	if (register_pernet_subsys(&rtnetlink_net_ops))

  		panic("rtnetlink_init: cannot initialize rtnetlink
  ");

  	netlink_set_nonroot(NETLINK_ROUTE, NL_NONROOT_RECV);
  	register_netdevice_notifier(&rtnetlink_dev_notifier);

  
  	rtnl_register(PF_UNSPEC, RTM_GETLINK, rtnl_getlink, rtnl_dump_ifinfo);
  	rtnl_register(PF_UNSPEC, RTM_SETLINK, rtnl_setlink, NULL);

  	rtnl_register(PF_UNSPEC, RTM_NEWLINK, rtnl_newlink, NULL);
  	rtnl_register(PF_UNSPEC, RTM_DELLINK, rtnl_dellink, NULL);

  
  	rtnl_register(PF_UNSPEC, RTM_GETADDR, NULL, rtnl_dump_all);
  	rtnl_register(PF_UNSPEC, RTM_GETROUTE, NULL, rtnl_dump_all);

  }
  
  EXPORT_SYMBOL(__rta_fill);

  EXPORT_SYMBOL(rtnetlink_put_metrics);

  EXPORT_SYMBOL(rtnl_lock);

  EXPORT_SYMBOL(rtnl_trylock);

  EXPORT_SYMBOL(rtnl_unlock);

  EXPORT_SYMBOL(rtnl_is_locked);

  EXPORT_SYMBOL(rtnl_unicast);

  EXPORT_SYMBOL(rtnl_notify);
  EXPORT_SYMBOL(rtnl_set_sk_err);

  EXPORT_SYMBOL(rtnl_create_link);
  EXPORT_SYMBOL(ifla_policy);