text: /*
   * Copyright (c) 1982, 1986, 1989, 1993
   *	The Regents of the University of California.  All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. All advertising materials mentioning features or use of this software
   *    must display the following acknowledgement:
   *	This product includes software developed by the University of
   *	California, Berkeley and its contributors.
   * 4. Neither the name of the University nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   *
   *	From: @(#)if.h	8.1 (Berkeley) 6/10/93
   * $FreeBSD: src/sys/net/if_var.h,v 1.18.2.16 2003/04/15 18:11:19 fjoe Exp $
   * $DragonFly: src/sys/net/if_var.h,v 1.71 2008/11/22 04:00:53 sephe Exp $
   */
  
  #ifndef	_NET_IF_VAR_H_
  #define	_NET_IF_VAR_H_
  
  #ifndef _SYS_SERIALIZE_H_
  #include <sys/serialize.h>
  #endif
  #ifndef _NET_IF_H_
  #include <net/if.h>
  #endif
  #ifndef _SYS_MUTEX_H_
  #include <sys/mutex.h>
  #endif
  
  /*
   * Structures defining a network interface, providing a packet
   * transport mechanism (ala level 0 of the PUP protocols).
   *
   * Each interface accepts output datagrams of a specified maximum
   * length, and provides higher level routines with input datagrams
   * received from its medium.
   *
   * Output occurs when the routine if_output is called, with four parameters:
   *	ifp->if_output(ifp, m, dst, rt)
   * Here m is the mbuf chain to be sent and dst is the destination address.
   * The output routine encapsulates the supplied datagram if necessary,
   * and then transmits it on its medium.
   *
   * On input, each interface unwraps the data received by it, and either
   * places it on the input queue of a internetwork datagram routine
   * and posts the associated software interrupt, or passes the datagram to
   * the routine if_input. It is called with the mbuf chain as parameter:
   *	ifp->if_input(ifp, m)
   * The input routine removes the protocol dependent header if necessary.
   *
   * Routines exist for locating interfaces by their addresses
   * or for locating a interface on a certain network, as well as more general
   * routing and gateway routines maintaining information used to locate
   * interfaces.  These routines live in the files if.c and route.c
   */
  
  /*
   * Forward structure declarations for function prototypes [sic].
   */
  struct	mbuf;
  struct	mbuf_chain;
  struct	proc;
  struct	rtentry;
  struct	rt_addrinfo;
  struct	socket;
  struct	ether_header;
  struct	ucred;
  struct	lwkt_serialize;
  struct	ifaddr_container;
  struct	ifaddr;
  struct	lwkt_port;
  struct	lwkt_msg;
  union	netmsg;
  struct	pktinfo;
  struct	ifpoll_info;
  
  #include <sys/queue.h>		/* get TAILQ macros */
  
  #include <net/altq/if_altq.h>
  
  #ifdef _KERNEL
  #include <sys/eventhandler.h>
  #include <sys/mbuf.h>
  #include <sys/systm.h>		/* XXX */
  #include <sys/thread2.h>
  #endif /* _KERNEL */
  
  #define IF_DUNIT_NONE   -1
  
  TAILQ_HEAD(ifnethead, ifnet);	/* we use TAILQs so that the order of */
  TAILQ_HEAD(ifaddrhead, ifaddr_container); /* instantiation is preserved in the list */
  TAILQ_HEAD(ifprefixhead, ifprefix);
  TAILQ_HEAD(ifmultihead, ifmultiaddr);
  
  /*
   * Structure defining a queue for a network interface.
   */
  struct	ifqueue {
  	struct	mbuf *ifq_head;
  	struct	mbuf *ifq_tail;
  	int	ifq_len;
  	int	ifq_maxlen;
  	int	ifq_drops;
  };
  
  /*
   * Note of DEVICE_POLLING
   * 1) Any file(*.c) that depends on DEVICE_POLLING supports in this
   *    file should include opt_polling.h at its beginning.
   * 2) When struct changes, which are conditioned by DEVICE_POLLING,
   *    are to be introduced, please keep the struct's size and layout
   *    same, no matter whether DEVICE_POLLING is defined or not.
   *    See ifnet.if_poll and ifnet.if_poll_unused for example.
   */
  
  #ifdef DEVICE_POLLING
  enum poll_cmd { POLL_ONLY, POLL_AND_CHECK_STATUS, POLL_DEREGISTER,
  		POLL_REGISTER };
  #endif
  
  enum ifnet_serialize {
  	IFNET_SERIALIZE_ALL,
  	IFNET_SERIALIZE_MAIN,
  	IFNET_SERIALIZE_TX_BASE = 0x10000000,
  	IFNET_SERIALIZE_RX_BASE = 0x20000000
  };
  #define IFNET_SERIALIZE_TX	IFNET_SERIALIZE_TX_BASE
  #define IFNET_SERIALIZE_RX(i)	(IFNET_SERIALIZE_RX_BASE + (i))
  
  #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
  
  /*
   * Structure defining a network interface.
   *
   * (Would like to call this struct ``if'', but C isn't PL/1.)
   */
  
  /*
   * NB: For FreeBSD, it is assumed that each NIC driver's softc starts with  
   * one of these structures, typically held within an arpcom structure.   
   * 
   *	struct <foo>_softc {
   *		struct arpcom {
   *			struct  ifnet ac_if;
   *			...
   *		} <arpcom> ;
   *		...   
   *	};
   *
   * The assumption is used in a number of places, including many
   * files in sys/net, device drivers, and sys/dev/mii.c:miibus_attach().
   * 
   * Unfortunately devices' softc are opaque, so we depend on this layout
   * to locate the struct ifnet from the softc in the generic code.
   *
   * MPSAFE NOTES: 
   *
   * ifnet is protected by calling if_serialize, if_tryserialize and
   * if_deserialize serialize functions with the ifnet_serialize parameter.
   * ifnet.if_snd is protected by its own spinlock.  Callers of if_ioctl,
   * if_watchdog, if_init, if_resolvemulti, and if_poll should call the
   * ifnet serialize functions with IFNET_SERIALIZE_ALL.  Callers of if_start
   * sould call the ifnet serialize functions with IFNET_SERIALIZE_TX.
   *
   * FIXME: Device drivers usually use the same serializer for their interrupt
   * FIXME: but this is not required.
   *
   * Caller of if_output must not serialize ifnet by calling ifnet serialize
   * functions; if_output will call the ifnet serialize functions based on
   * its own needs.  Caller of if_input does not necessarily hold the related
   * serializer.
   *
   * If a device driver installs the same serializer for its interrupt
   * as for ifnet, then the driver only really needs to worry about further
   * serialization in timeout based entry points.  All other entry points
   * will already be serialized.  Older ISA drivers still using the old
   * interrupt infrastructure will have to obtain and release the serializer
   * in their interrupt routine themselves.
   */
  struct ifnet {
  	void	*if_softc;		/* pointer to driver state */
  	void	*if_l2com;		/* pointer to protocol bits */
  	TAILQ_ENTRY(ifnet) if_link;	/* all struct ifnets are chained */
  	char	if_xname[IFNAMSIZ];	/* external name (name + unit) */
  	const char *if_dname;		/* driver name */
  	int	if_dunit;		/* unit or IF_DUNIT_NONE */
  	void	*if_vlantrunks;		/* vlan trunks */
  	struct	ifaddrhead *if_addrheads; /* array[NCPU] of TAILQs of addresses per if */
  	int	if_pcount;		/* number of promiscuous listeners */
  	void	*if_carp;		/* carp interfaces */
  	struct	bpf_if *if_bpf;		/* packet filter structure */
  	u_short	if_index;		/* numeric abbreviation for this if  */
  	short	if_timer;		/* time 'til if_watchdog called */
  	int	if_flags;		/* up/down, broadcast, etc. */
  	int	if_capabilities;	/* interface capabilities */
  	int	if_capenable;		/* enabled features */
  	void	*if_linkmib;		/* link-type-specific MIB data */
  	size_t	if_linkmiblen;		/* length of above data */
  	struct	if_data if_data;
  	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
  	int	if_amcount;		/* number of all-multicast requests */
  /* procedure handles */
  	int	(*if_output)		/* output routine (enqueue) */
  		(struct ifnet *, struct mbuf *, struct sockaddr *,
  		     struct rtentry *);
  	void	(*if_input)		/* input routine from hardware driver */
  		(struct ifnet *, struct mbuf *);
  	void	(*if_start)		/* initiate output routine */
  		(struct ifnet *);
  	int	(*if_ioctl)		/* ioctl routine */
  		(struct ifnet *, u_long, caddr_t, struct ucred *);
  	void	(*if_watchdog)		/* timer routine */
  		(struct ifnet *);
  	void	(*if_init)		/* Init routine */
  		(void *);
  	int	(*if_resolvemulti)	/* validate/resolve multicast */
  		(struct ifnet *, struct sockaddr **, struct sockaddr *);
  	int	(*if_start_cpuid)	/* cpuid to run if_start */
  		(struct ifnet *);
  	TAILQ_HEAD(, ifg_list) if_groups; /* linked list of groups per if */
  #ifdef DEVICE_POLLING
  	void	(*if_poll)		/* IFF_POLLING support */
  		(struct ifnet *, enum poll_cmd, int);
  	int	if_poll_cpuid;
  #else
  	/* Place holders */
  	void	(*if_poll_unused)(void);
  	int	if_poll_cpuid_used;
  #endif
  	void	(*if_serialize)
  		(struct ifnet *, enum ifnet_serialize);
  	void	(*if_deserialize)
  		(struct ifnet *, enum ifnet_serialize);
  	int	(*if_tryserialize)
  		(struct ifnet *, enum ifnet_serialize);
  #ifdef INVARIANTS
  	void	(*if_serialize_assert)
  		(struct ifnet *, enum ifnet_serialize, boolean_t);
  #else
  	/* Place holders */
  	void	(*if_serialize_unused)(void);
  #endif
  #ifdef IFPOLL_ENABLE
  	void	(*if_qpoll)
  		(struct ifnet *, struct ifpoll_info *);
  #else
  	/* Place holders */
  	void	(*if_qpoll_unused)(void);
  #endif
  	struct	ifaltq if_snd;		/* output queue (includes altq) */
  	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
  	const uint8_t	*if_broadcastaddr;
  	void	*if_bridge;		/* bridge glue */
  	void	*if_afdata[AF_MAX];
  	struct ifaddr	*if_lladdr;
  	struct lwkt_serialize *if_serializer;	/* serializer or MP lock */
  	struct lwkt_serialize if_default_serializer; /* if not supplied */
  	struct mtx	if_ioctl_mtx;	/* high-level ioctl serializing mutex */
  	int	if_cpuid;
  	struct netmsg_base *if_start_nmsg; /* percpu msgs to sched if_start */
  	void	*if_pf_kif; /* pf interface abstraction */
   	union {
   		void *carp_s;		/* carp structure (used by !carp ifs) */
   		struct ifnet *carp_d;	/* ptr to carpdev (used by carp ifs) */
   	} if_carp_ptr;
  	#define if_carp		if_carp_ptr.carp_s
  	#define if_carpdev	if_carp_ptr.carp_d
  };
  typedef void if_init_f_t (void *);
  
  #define	if_mtu		if_data.ifi_mtu
  #define	if_type		if_data.ifi_type
  #define if_physical	if_data.ifi_physical
  #define	if_addrlen	if_data.ifi_addrlen
  #define	if_hdrlen	if_data.ifi_hdrlen
  #define	if_metric	if_data.ifi_metric
  #define	if_link_state	if_data.ifi_link_state
  #define	if_baudrate	if_data.ifi_baudrate
  #define	if_hwassist	if_data.ifi_hwassist
  #define	if_ipackets	if_data.ifi_ipackets
  #define	if_ierrors	if_data.ifi_ierrors
  #define	if_opackets	if_data.ifi_opackets
  #define	if_oerrors	if_data.ifi_oerrors
  #define	if_collisions	if_data.ifi_collisions
  #define	if_ibytes	if_data.ifi_ibytes
  #define	if_obytes	if_data.ifi_obytes
  #define	if_imcasts	if_data.ifi_imcasts
  #define	if_omcasts	if_data.ifi_omcasts
  #define	if_iqdrops	if_data.ifi_iqdrops
  #define	if_noproto	if_data.ifi_noproto
  #define	if_lastchange	if_data.ifi_lastchange
  #define if_recvquota	if_data.ifi_recvquota
  #define	if_xmitquota	if_data.ifi_xmitquota
  #define if_rawoutput(if, m, sa) if_output(if, m, sa, NULL)
  
  /* for compatibility with other BSDs */
  #define	if_list		if_link
  
  #endif
  
  /*
   * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
   * are queues of messages stored on ifqueue structures
   * (defined above).  Entries are added to and deleted from these structures
   * by these macros, which should be called with ipl raised to splimp().
   */
  #define	IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
  #define	IF_DROP(ifq)		((ifq)->ifq_drops++)
  #define	IF_QLEN(ifq)		((ifq)->ifq_len)
  #define	IF_QEMPTY(ifq)		(IF_QLEN(ifq) == 0)
  
  #define	IF_ENQUEUE(ifq, m) do {						\
  	(m)->m_nextpkt = 0;						\
  	if ((ifq)->ifq_tail == 0)					\
  		(ifq)->ifq_head = m;					\
  	else								\
  		(ifq)->ifq_tail->m_nextpkt = m;				\
  	(ifq)->ifq_tail = m;						\
  	(ifq)->ifq_len++;						\
  } while (0)
  
  #define	IF_PREPEND(ifq, m) do {						\
  	(m)->m_nextpkt = (ifq)->ifq_head;				\
  	if ((ifq)->ifq_tail == 0)					\
  		(ifq)->ifq_tail = (m);					\
  	(ifq)->ifq_head = (m);						\
  	(ifq)->ifq_len++;						\
  } while (0)
  
  #define	IF_DEQUEUE(ifq, m) do {						\
  	(m) = (ifq)->ifq_head;						\
  	if (m) {							\
  		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0)		\
  			(ifq)->ifq_tail = 0;				\
  		(m)->m_nextpkt = 0;					\
  		(ifq)->ifq_len--;					\
  	}								\
  } while (0)
  
  #define	IF_POLL(ifq, m)		((m) = (ifq)->ifq_head)
  
  #define IF_DRAIN(ifq) do {						\
  	struct mbuf *m;							\
  	while (1) {							\
  		IF_DEQUEUE(ifq, m);					\
  		if (m == NULL)						\
  			break;						\
  		m_freem(m);						\
  	}								\
  } while (0)
  
  #ifdef _KERNEL
  
  /* interface link layer address change event */
  typedef void (*iflladdr_event_handler_t)(void *, struct ifnet *);
  EVENTHANDLER_DECLARE(iflladdr_event, iflladdr_event_handler_t);
  
  #ifdef INVARIANTS
  #define ASSERT_IFNET_SERIALIZED_ALL(ifp) \
  	(ifp)->if_serialize_assert((ifp), IFNET_SERIALIZE_ALL, TRUE)
  #define ASSERT_IFNET_NOT_SERIALIZED_ALL(ifp) \
  	(ifp)->if_serialize_assert((ifp), IFNET_SERIALIZE_ALL, FALSE)
  
  #define ASSERT_IFNET_SERIALIZED_TX(ifp) \
  	(ifp)->if_serialize_assert((ifp), IFNET_SERIALIZE_TX, TRUE)
  #define ASSERT_IFNET_NOT_SERIALIZED_TX(ifp) \
  	(ifp)->if_serialize_assert((ifp), IFNET_SERIALIZE_TX, FALSE)
  
  #define ASSERT_IFNET_SERIALIZED_MAIN(ifp) \
  	(ifp)->if_serialize_assert((ifp), IFNET_SERIALIZE_MAIN, TRUE)
  #define ASSERT_IFNET_NOT_SERIALIZED_MAIN(ifp) \
  	(ifp)->if_serialize_assert((ifp), IFNET_SERIALIZE_MAIN, FALSE)
  #else
  #define ASSERT_IFNET_SERIALIZED_ALL(ifp)	((void)0)
  #define ASSERT_IFNET_NOT_SERIALIZED_ALL(ifp)	((void)0)
  #define ASSERT_IFNET_SERIALIZED_TX(ifp)		((void)0)
  #define ASSERT_IFNET_NOT_SERIALIZED_TX(ifp)	((void)0)
  #define ASSERT_IFNET_SERIALIZED_MAIN(ifp)	((void)0)
  #define ASSERT_IFNET_NOT_SERIALIZED_MAIN(ifp)	((void)0)
  #endif
  
  static __inline void
  ifnet_serialize_all(struct ifnet *_ifp)
  {
  	_ifp->if_serialize(_ifp, IFNET_SERIALIZE_ALL);
  }
  
  static __inline void
  ifnet_deserialize_all(struct ifnet *_ifp)
  {
  	_ifp->if_deserialize(_ifp, IFNET_SERIALIZE_ALL);
  }
  
  static __inline int
  ifnet_tryserialize_all(struct ifnet *_ifp)
  {
  	return _ifp->if_tryserialize(_ifp, IFNET_SERIALIZE_ALL);
  }
  
  static __inline void
  ifnet_serialize_tx(struct ifnet *_ifp)
  {
  	_ifp->if_serialize(_ifp, IFNET_SERIALIZE_TX);
  }
  
  static __inline void
  ifnet_deserialize_tx(struct ifnet *_ifp)
  {
  	_ifp->if_deserialize(_ifp, IFNET_SERIALIZE_TX);
  }
  
  static __inline int
  ifnet_tryserialize_tx(struct ifnet *_ifp)
  {
  	return _ifp->if_tryserialize(_ifp, IFNET_SERIALIZE_TX);
  }
  
  static __inline void
  ifnet_serialize_main(struct ifnet *_ifp)
  {
  	_ifp->if_serialize(_ifp, IFNET_SERIALIZE_MAIN);
  }
  
  static __inline void
  ifnet_deserialize_main(struct ifnet *_ifp)
  {
  	_ifp->if_deserialize(_ifp, IFNET_SERIALIZE_MAIN);
  }
  
  static __inline int
  ifnet_tryserialize_main(struct ifnet *_ifp)
  {
  	return _ifp->if_tryserialize(_ifp, IFNET_SERIALIZE_MAIN);
  }
  
  /*
   * DEPRECATED - should not be used by any new driver.  This code uses the
   * old queueing interface and if_start ABI and does not use the ifp's
   * serializer.
   */
  #define IF_HANDOFF(ifq, m, ifp)			if_handoff(ifq, m, ifp, 0)
  #define IF_HANDOFF_ADJ(ifq, m, ifp, adj)	if_handoff(ifq, m, ifp, adj)
  
  static __inline int
  if_handoff(struct ifqueue *_ifq, struct mbuf *_m, struct ifnet *_ifp,
  	   int _adjust)
  {
  	int _need_if_start = 0;
  
  	crit_enter(); 
  
  	if (IF_QFULL(_ifq)) {
  		IF_DROP(_ifq);
  		crit_exit();
  		m_freem(_m);
  		return (0);
  	}
  	if (_ifp != NULL) {
  		_ifp->if_obytes += _m->m_pkthdr.len + _adjust;
  		if (_m->m_flags & M_MCAST)
  			_ifp->if_omcasts++;
  		_need_if_start = !(_ifp->if_flags & IFF_OACTIVE);
  	}
  	IF_ENQUEUE(_ifq, _m);
  	if (_need_if_start) {
  		(*_ifp->if_start)(_ifp);
  	}
  	crit_exit();
  	return (1);
  }
  
  /*
   * 72 was chosen below because it is the size of a TCP/IP
   * header (40) + the minimum mss (32).
   */
  #define	IF_MINMTU	72
  #define	IF_MAXMTU	65535
  
  #endif /* _KERNEL */
  
  struct in_ifaddr;
  
  struct in_ifaddr_container {
  	struct in_ifaddr	*ia;
  	LIST_ENTRY(in_ifaddr_container) ia_hash;
  				/* entry in bucket of inet addresses */
  	TAILQ_ENTRY(in_ifaddr_container) ia_link;
  				/* list of internet addresses */
  	struct ifaddr_container	*ia_ifac; /* parent ifaddr_container */
  };
  
  struct ifaddr_container {
  #define IFA_CONTAINER_MAGIC	0x19810219
  #define IFA_CONTAINER_DEAD	0xc0dedead
  	uint32_t		ifa_magic;  /* IFA_CONTAINER_MAGIC */
  	struct ifaddr		*ifa;
  	TAILQ_ENTRY(ifaddr_container)	ifa_link;   /* queue macro glue */
  	u_int			ifa_refcnt; /* references to this structure */
  	uint16_t		ifa_listmask;	/* IFA_LIST_ */
  	uint16_t		ifa_prflags;	/* protocol specific flags */
  
  	/*
  	 * Protocol specific states
  	 */
  	union {
  		struct in_ifaddr_container u_in_ifac;
  	} ifa_proto_u;
  };
  
  #define IFA_LIST_IFADDRHEAD	0x01	/* on ifnet.if_addrheads[cpuid] */
  #define IFA_LIST_IN_IFADDRHEAD	0x02	/* on in_ifaddrheads[cpuid] */
  #define IFA_LIST_IN_IFADDRHASH	0x04	/* on in_ifaddrhashtbls[cpuid] */
  
  #define IFA_PRF_FLAG0		0x01
  #define IFA_PRF_FLAG1		0x02
  #define IFA_PRF_FLAG2		0x04
  #define IFA_PRF_FLAG3		0x08
  
  /*
   * The ifaddr structure contains information about one address
   * of an interface.  They are maintained by the different address families,
   * are allocated and attached when an address is set, and are linked
   * together so all addresses for an interface can be located.
   */
  struct ifaddr {
  	struct	sockaddr *ifa_addr;	/* address of interface */
  	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
  #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
  	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
  	struct	if_data if_data;	/* not all members are meaningful */
  	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
  	void	*ifa_link_pad;
  	struct ifaddr_container *ifa_containers;
  	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
  		(int, struct rtentry *, struct rt_addrinfo *);
  	u_short	ifa_flags;		/* mostly rt_flags for cloning */
  	int	ifa_ncnt;		/* # of valid ifaddr_container */
  	int	ifa_metric;		/* cost of going out this interface */
  #ifdef notdef
  	struct	rtentry *ifa_rt;	/* XXXX for ROUTETOIF ????? */
  #endif
  	int (*ifa_claim_addr)		/* check if an addr goes to this if */
  		(struct ifaddr *, struct sockaddr *);
  
  };
  #define	IFA_ROUTE	RTF_UP		/* route installed */
  
  /* for compatibility with other BSDs */
  #define	ifa_list	ifa_link
  
  /*
   * The prefix structure contains information about one prefix
   * of an interface.  They are maintained by the different address families,
   * are allocated and attached when an prefix or an address is set,
   * and are linked together so all prefixes for an interface can be located.
   */
  struct ifprefix {
  	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
  	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
  	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
  	u_char	ifpr_plen;		/* prefix length in bits */
  	u_char	ifpr_type;		/* protocol dependent prefix type */
  };
  
  /*
   * Multicast address structure.  This is analogous to the ifaddr
   * structure except that it keeps track of multicast addresses.
   * Also, the reference count here is a count of requests for this
   * address, not a count of pointers to this structure.
   */
  struct ifmultiaddr {
  	TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
  	struct	sockaddr *ifma_addr;	/* address this membership is for */
  	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
  	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
  	u_int	ifma_refcount;		/* reference count */
  	void	*ifma_protospec;	/* protocol-specific state, if any */
  };
  
  #ifdef _KERNEL
  
  enum ifaddr_event {
  	IFADDR_EVENT_ADD,
  	IFADDR_EVENT_DELETE,
  	IFADDR_EVENT_CHANGE
  };
  
  /* interface address change event */
  typedef void (*ifaddr_event_handler_t)(void *, struct ifnet *,
  	enum ifaddr_event, struct ifaddr *);
  EVENTHANDLER_DECLARE(ifaddr_event, ifaddr_event_handler_t);
  /* new interface attach event */
  typedef void (*ifnet_attach_event_handler_t)(void *, struct ifnet *);
  EVENTHANDLER_DECLARE(ifnet_attach_event, ifnet_attach_event_handler_t);
  /* interface detach event */
  typedef void (*ifnet_detach_event_handler_t)(void *, struct ifnet *);
  EVENTHANDLER_DECLARE(ifnet_detach_event, ifnet_detach_event_handler_t);
  
  /*
   * interface groups
   */
  struct ifg_group {
  	char				 ifg_group[IFNAMSIZ];
  	u_int				 ifg_refcnt;
  	void				*ifg_pf_kif;
  	int				 ifg_carp_demoted;
  	TAILQ_HEAD(, ifg_member)	 ifg_members;
  	TAILQ_ENTRY(ifg_group)		 ifg_next;
  };
  
  struct ifg_member {
  	TAILQ_ENTRY(ifg_member)	 ifgm_next;
  	struct ifnet		*ifgm_ifp;
  };
  
  struct ifg_list {
  	struct ifg_group	*ifgl_group;
  	TAILQ_ENTRY(ifg_list)	 ifgl_next;
  };
  
  /* group attach event */
  typedef void (*group_attach_event_handler_t)(void *, struct ifg_group *);
  EVENTHANDLER_DECLARE(group_attach_event, group_attach_event_handler_t);
  /* group detach event */
  typedef void (*group_detach_event_handler_t)(void *, struct ifg_group *);
  EVENTHANDLER_DECLARE(group_detach_event, group_detach_event_handler_t);
  /* group change event */
  typedef void (*group_change_event_handler_t)(void *, const char *);
  EVENTHANDLER_DECLARE(group_change_event, group_change_event_handler_t);
  
  
  #ifdef INVARIANTS
  #define ASSERT_IFAC_VALID(ifac)	do { \
  	KKASSERT((ifac)->ifa_magic == IFA_CONTAINER_MAGIC); \
  	KKASSERT((ifac)->ifa_refcnt > 0); \
  } while (0)
  #else
  #define ASSERT_IFAC_VALID(ifac)	((void)0)
  #endif
  
  static __inline void
  _IFAREF(struct ifaddr *_ifa, int _cpu_id)
  {
  	struct ifaddr_container *_ifac = &_ifa->ifa_containers[_cpu_id];
  
  	crit_enter();
  	ASSERT_IFAC_VALID(_ifac);
  	++_ifac->ifa_refcnt;
  	crit_exit();
  }
  
  static __inline void
  IFAREF(struct ifaddr *_ifa)
  {
  	_IFAREF(_ifa, mycpuid);
  }
  
  #include <sys/malloc.h>
  
  MALLOC_DECLARE(M_IFADDR);
  MALLOC_DECLARE(M_IFMADDR);
  MALLOC_DECLARE(M_IFNET);
  
  void	ifac_free(struct ifaddr_container *, int);
  
  static __inline void
  _IFAFREE(struct ifaddr *_ifa, int _cpu_id)
  {
  	struct ifaddr_container *_ifac = &_ifa->ifa_containers[_cpu_id];
  
  	crit_enter();
  	ASSERT_IFAC_VALID(_ifac);
  	if (--_ifac->ifa_refcnt == 0)
  		ifac_free(_ifac, _cpu_id);
  	crit_exit();
  }
  
  static __inline void
  IFAFREE(struct ifaddr *_ifa)
  {
  	_IFAFREE(_ifa, mycpuid);
  }
  
  struct lwkt_port *ifnet_portfn(int);
  int	ifnet_domsg(struct lwkt_msg *, int);
  void	ifnet_sendmsg(struct lwkt_msg *, int);
  void	ifnet_forwardmsg(struct lwkt_msg *, int);
  struct ifnet *ifnet_byindex(unsigned short);
  
  static __inline int
  ifa_domsg(struct lwkt_msg *_lmsg, int _cpu)
  {
  	return ifnet_domsg(_lmsg, _cpu);
  }
  
  static __inline void
  ifa_sendmsg(struct lwkt_msg *_lmsg, int _cpu)
  {
  	ifnet_sendmsg(_lmsg, _cpu);
  }
  
  static __inline void
  ifa_forwardmsg(struct lwkt_msg *_lmsg, int _nextcpu)
  {
  	ifnet_forwardmsg(_lmsg, _nextcpu);
  }
  
  #define REINPUT_KEEPRCVIF	0x0001	/* ether_reinput_oncpu() */
  #define REINPUT_RUNBPF 		0x0002	/* ether_reinput_oncpu() */
  
  
  extern	struct ifnethead ifnet;
  extern struct	ifnet	**ifindex2ifnet;
  extern	int ifqmaxlen;
  extern	struct ifnet loif[];
  extern	int if_index;
  
  void	ether_ifattach(struct ifnet *, uint8_t *, struct lwkt_serialize *);
  void	ether_ifattach_bpf(struct ifnet *, uint8_t *, u_int, u_int,
  			struct lwkt_serialize *);
  void	ether_ifdetach(struct ifnet *);
  void	ether_demux(struct mbuf *);
  void	ether_demux_oncpu(struct ifnet *, struct mbuf *);
  void	ether_reinput_oncpu(struct ifnet *, struct mbuf *, int);
  void	ether_input_chain(struct ifnet *, struct mbuf *,
  			  const struct pktinfo *, struct mbuf_chain *);
  void	ether_input_chain_init(struct mbuf_chain *);
  void	ether_input_dispatch(struct mbuf_chain *);
  int	ether_output_frame(struct ifnet *, struct mbuf *);
  int	ether_ioctl(struct ifnet *, u_long, caddr_t);
  struct ifnet *ether_bridge_interface(struct ifnet *ifp);
  uint32_t	ether_crc32_le(const uint8_t *, size_t);
  uint32_t	ether_crc32_be(const uint8_t *, size_t);
  
  int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
  int	if_allmulti(struct ifnet *, int);
  void	if_attach(struct ifnet *, struct lwkt_serialize *);
  int	if_delmulti(struct ifnet *, struct sockaddr *);
  void	if_delallmulti(struct ifnet *ifp);
  void	if_purgeaddrs_nolink(struct ifnet *);
  void	if_detach(struct ifnet *);
  void	if_down(struct ifnet *);
  void	if_link_state_change(struct ifnet *);
  void	if_initname(struct ifnet *, const char *, int);
  int	if_getanyethermac(uint16_t *, int);
  int	if_printf(struct ifnet *, const char *, ...) __printflike(2, 3);
  struct ifnet *if_alloc(uint8_t);
  void	if_free(struct ifnet *);
  void	if_route(struct ifnet *, int flag, int fam);
  int	if_setlladdr(struct ifnet *, const u_char *, int);
  void	if_unroute(struct ifnet *, int flag, int fam);
  void	if_up(struct ifnet *);
  /*void	ifinit(void);*/ /* declared in systm.h for main() */
  int	ifioctl(struct socket *, u_long, caddr_t, struct ucred *);
  int	ifpromisc(struct ifnet *, int);
  struct	ifnet *ifunit(const char *);
  struct	ifnet *if_withname(struct sockaddr *);
  
  struct	ifg_group *if_creategroup(const char *);
  int     if_addgroup(struct ifnet *, const char *);
  int     if_delgroup(struct ifnet *, const char *);
  int     if_getgroup(caddr_t, struct ifnet *);
  int     if_getgroupmembers(caddr_t);
  
  struct	ifaddr *ifa_ifwithaddr(struct sockaddr *);
  struct	ifaddr *ifa_ifwithdstaddr(struct sockaddr *);
  struct	ifaddr *ifa_ifwithnet(struct sockaddr *);
  struct	ifaddr *ifa_ifwithroute(int, struct sockaddr *, struct sockaddr *);
  struct	ifaddr *ifaof_ifpforaddr(struct sockaddr *, struct ifnet *);
  
  typedef void *if_com_alloc_t(u_char type, struct ifnet *ifp);
  typedef void if_com_free_t(void *com, u_char type);
  void    if_register_com_alloc(u_char, if_com_alloc_t *a, if_com_free_t *);
  void    if_deregister_com_alloc(u_char);
  
  void	*ifa_create(int, int);
  void	ifa_destroy(struct ifaddr *);
  void	ifa_iflink(struct ifaddr *, struct ifnet *, int);
  void	ifa_ifunlink(struct ifaddr *, struct ifnet *);
  
  struct ifaddr *ifaddr_byindex(unsigned short);
  
  struct	ifmultiaddr *ifmaof_ifpforaddr(struct sockaddr *, struct ifnet *);
  int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
  void	if_devstart(struct ifnet *ifp);
  
  #define IF_LLSOCKADDR(ifp)						\
      ((struct sockaddr_dl *)(ifp)->if_lladdr->ifa_addr)
  #define IF_LLADDR(ifp)	LLADDR(IF_LLSOCKADDR(ifp))
  
  #ifdef DEVICE_POLLING
  typedef	void poll_handler_t (struct ifnet *ifp, enum poll_cmd cmd, int count);
  int	ether_poll_register(struct ifnet *);
  int	ether_poll_deregister(struct ifnet *);
  int	ether_pollcpu_register(struct ifnet *, int);
  #endif /* DEVICE_POLLING */
  
  #ifdef IFPOLL_ENABLE
  int	ifpoll_register(struct ifnet *);
  int	ifpoll_deregister(struct ifnet *);
  #endif	/* IFPOLL_ENABLE */
  
  #endif /* _KERNEL */
  
  #endif /* !_NET_IF_VAR_H_ */
  