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/*-
 * 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. 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.
 *
 *	@(#)if.h	8.1 (Berkeley) 6/10/93
 * $FreeBSD$
 */

#ifndef _NET_IF_H_
#define	_NET_IF_H_

#include <sys/cdefs.h>

#if __BSD_VISIBLE
/*
 * <net/if.h> does not depend on <sys/time.h> on most other systems.  This
 * helps userland compatibility.  (struct timeval ifi_lastchange)
 * The same holds for <sys/socket.h>.  (struct sockaddr ifru_addr)
 */
#ifndef _KERNEL
#include <sys/time.h>
#include <sys/socket.h>
#endif
#endif

/*
 * Length of interface external name, including terminating '\0'.
 * Note: this is the same size as a generic device's external name.
 */
#define		IF_NAMESIZE	16
#if __BSD_VISIBLE
#define		IFNAMSIZ	IF_NAMESIZE
#define		IF_MAXUNIT	0x7fff	/* historical value */
#endif
#if __BSD_VISIBLE

/*
 * Structure used to query names of interface cloners.
 */

struct if_clonereq {
	int	ifcr_total;		/* total cloners (out) */
	int	ifcr_count;		/* room for this many in user buffer */
	char	*ifcr_buffer;		/* buffer for cloner names */
};

/*
 * Structure describing information about an interface
 * which may be of interest to management entities.
 */
struct if_data {
	/* generic interface information */
	uint8_t	ifi_type;		/* ethernet, tokenring, etc */
	uint8_t	ifi_physical;		/* e.g., AUI, Thinnet, 10base-T, etc */
	uint8_t	ifi_addrlen;		/* media address length */
	uint8_t	ifi_hdrlen;		/* media header length */
	uint8_t	ifi_link_state;		/* current link state */
	uint8_t	ifi_vhid;		/* carp vhid */
	uint16_t	ifi_datalen;	/* length of this data struct */
	uint32_t	ifi_mtu;	/* maximum transmission unit */
	uint32_t	ifi_metric;	/* routing metric (external only) */
	uint64_t	ifi_baudrate;	/* linespeed */
	/* volatile statistics */
	uint64_t	ifi_ipackets;	/* packets received on interface */
	uint64_t	ifi_ierrors;	/* input errors on interface */
	uint64_t	ifi_opackets;	/* packets sent on interface */
	uint64_t	ifi_oerrors;	/* output errors on interface */
	uint64_t	ifi_collisions;	/* collisions on csma interfaces */
	uint64_t	ifi_ibytes;	/* total number of octets received */
	uint64_t	ifi_obytes;	/* total number of octets sent */
	uint64_t	ifi_imcasts;	/* packets received via multicast */
	uint64_t	ifi_omcasts;	/* packets sent via multicast */
	uint64_t	ifi_iqdrops;	/* dropped on input */
	uint64_t	ifi_oqdrops;	/* dropped on output */
	uint64_t	ifi_noproto;	/* destined for unsupported protocol */
	uint64_t	ifi_hwassist;	/* HW offload capabilities, see IFCAP */

	/* Unions are here to make sizes MI. */
	union {				/* uptime at attach or stat reset */
		time_t		tt;
		uint64_t	ph;
	} __ifi_epoch;
#define	ifi_epoch	__ifi_epoch.tt
	union {				/* time of last administrative change */
		struct timeval	tv;
		struct {
			uint64_t ph1;
			uint64_t ph2;
		} ph;
	} __ifi_lastchange;
#define	ifi_lastchange	__ifi_lastchange.tv
};

/*-
 * Interface flags are of two types: network stack owned flags, and driver
 * owned flags.  Historically, these values were stored in the same ifnet
 * flags field, but with the advent of fine-grained locking, they have been
 * broken out such that the network stack is responsible for synchronizing
 * the stack-owned fields, and the device driver the device-owned fields.
 * Both halves can perform lockless reads of the other half's field, subject
 * to accepting the involved races.
 *
 * Both sets of flags come from the same number space, and should not be
 * permitted to conflict, as they are exposed to user space via a single
 * field.
 *
 * The following symbols identify read and write requirements for fields:
 *
 * (i) if_flags field set by device driver before attach, read-only there
 *     after.
 * (n) if_flags field written only by the network stack, read by either the
 *     stack or driver.
 * (d) if_drv_flags field written only by the device driver, read by either
 *     the stack or driver.
 */
#define	IFF_UP		0x1		/* (n) interface is up */
#define	IFF_BROADCAST	0x2		/* (i) broadcast address valid */
#define	IFF_DEBUG	0x4		/* (n) turn on debugging */
#define	IFF_LOOPBACK	0x8		/* (i) is a loopback net */
#define	IFF_POINTOPOINT	0x10		/* (i) is a point-to-point link */
/*			0x20		   was IFF_SMART */
#define	IFF_DRV_RUNNING	0x40		/* (d) resources allocated */
#define	IFF_NOARP	0x80		/* (n) no address resolution protocol */
#define	IFF_PROMISC	0x100		/* (n) receive all packets */
#define	IFF_ALLMULTI	0x200		/* (n) receive all multicast packets */
#define	IFF_DRV_OACTIVE	0x400		/* (d) tx hardware queue is full */
#define	IFF_SIMPLEX	0x800		/* (i) can't hear own transmissions */
#define	IFF_LINK0	0x1000		/* per link layer defined bit */
#define	IFF_LINK1	0x2000		/* per link layer defined bit */
#define	IFF_LINK2	0x4000		/* per link layer defined bit */
#define	IFF_ALTPHYS	IFF_LINK2	/* use alternate physical connection */
#define	IFF_MULTICAST	0x8000		/* (i) supports multicast */
#define	IFF_CANTCONFIG	0x10000		/* (i) unconfigurable using ioctl(2) */
#define	IFF_PPROMISC	0x20000		/* (n) user-requested promisc mode */
#define	IFF_MONITOR	0x40000		/* (n) user-requested monitor mode */
#define	IFF_STATICARP	0x80000		/* (n) static ARP */
#define	IFF_DYING	0x200000	/* (n) interface is winding down */
#define	IFF_RENAMING	0x400000	/* (n) interface is being renamed */
/*
 * Old names for driver flags so that user space tools can continue to use
 * the old (portable) names.
 */
#ifndef _KERNEL
#define	IFF_RUNNING	IFF_DRV_RUNNING
#define	IFF_OACTIVE	IFF_DRV_OACTIVE
#endif

/* flags set internally only: */
#define	IFF_CANTCHANGE \
	(IFF_BROADCAST|IFF_POINTOPOINT|IFF_DRV_RUNNING|IFF_DRV_OACTIVE|\
	    IFF_SIMPLEX|IFF_MULTICAST|IFF_ALLMULTI|IFF_PROMISC|\
	    IFF_DYING|IFF_CANTCONFIG)

/*
 * Values for if_link_state.
 */
#define	LINK_STATE_UNKNOWN	0	/* link invalid/unknown */
#define	LINK_STATE_DOWN		1	/* link is down */
#define	LINK_STATE_UP		2	/* link is up */

/*
 * Some convenience macros used for setting ifi_baudrate.
 * XXX 1000 vs. 1024? --thorpej@netbsd.org
 */
#define	IF_Kbps(x)	((uintmax_t)(x) * 1000)	/* kilobits/sec. */
#define	IF_Mbps(x)	(IF_Kbps((x) * 1000))	/* megabits/sec. */
#define	IF_Gbps(x)	(IF_Mbps((x) * 1000))	/* gigabits/sec. */

/*
 * Capabilities that interfaces can advertise.
 *
 * struct ifnet.if_capabilities
 *   contains the optional features & capabilities a particular interface
 *   supports (not only the driver but also the detected hw revision).
 *   Capabilities are defined by IFCAP_* below.
 * struct ifnet.if_capenable
 *   contains the enabled (either by default or through ifconfig) optional
 *   features & capabilities on this interface.
 *   Capabilities are defined by IFCAP_* below.
 * struct if_data.ifi_hwassist in mbuf CSUM_ flag form, controlled by above
 *   contains the enabled optional feature & capabilites that can be used
 *   individually per packet and are specified in the mbuf pkthdr.csum_flags
 *   field.  IFCAP_* and CSUM_* do not match one to one and CSUM_* may be
 *   more detailed or differenciated than IFCAP_*.
 *   Hwassist features are defined CSUM_* in sys/mbuf.h
 *
 * Capabilities that cannot be arbitrarily changed with ifconfig/ioctl
 * are listed in IFCAP_CANTCHANGE, similar to IFF_CANTCHANGE.
 * This is not strictly necessary because the common code never
 * changes capabilities, and it is left to the individual driver
 * to do the right thing. However, having the filter here
 * avoids replication of the same code in all individual drivers.
 */
#define	IFCAP_RXCSUM		0x00001  /* can offload checksum on RX */
#define	IFCAP_TXCSUM		0x00002  /* can offload checksum on TX */
#define	IFCAP_NETCONS		0x00004  /* can be a network console */
#define	IFCAP_VLAN_MTU		0x00008	/* VLAN-compatible MTU */
#define	IFCAP_VLAN_HWTAGGING	0x00010	/* hardware VLAN tag support */
#define	IFCAP_JUMBO_MTU		0x00020	/* 9000 byte MTU supported */
#define	IFCAP_POLLING		0x00040	/* driver supports polling */
#define	IFCAP_VLAN_HWCSUM	0x00080	/* can do IFCAP_HWCSUM on VLANs */
#define	IFCAP_TSO4		0x00100	/* can do TCP Segmentation Offload */
#define	IFCAP_TSO6		0x00200	/* can do TCP6 Segmentation Offload */
#define	IFCAP_LRO		0x00400	/* can do Large Receive Offload */
#define	IFCAP_WOL_UCAST		0x00800	/* wake on any unicast frame */
#define	IFCAP_WOL_MCAST		0x01000	/* wake on any multicast frame */
#define	IFCAP_WOL_MAGIC		0x02000	/* wake on any Magic Packet */
#define	IFCAP_TOE4		0x04000	/* interface can offload TCP */
#define	IFCAP_TOE6		0x08000	/* interface can offload TCP6 */
#define	IFCAP_VLAN_HWFILTER	0x10000 /* interface hw can filter vlan tag */
#define	IFCAP_POLLING_NOCOUNT	0x20000 /* polling ticks cannot be fragmented */
#define	IFCAP_VLAN_HWTSO	0x40000 /* can do IFCAP_TSO on VLANs */
#define	IFCAP_LINKSTATE		0x80000 /* the runtime link state is dynamic */
#define	IFCAP_NETMAP		0x100000 /* netmap mode supported/enabled */
#define	IFCAP_RXCSUM_IPV6	0x200000  /* can offload checksum on IPv6 RX */
#define	IFCAP_TXCSUM_IPV6	0x400000  /* can offload checksum on IPv6 TX */
#define	IFCAP_HWSTATS		0x800000 /* manages counters internally */
#define	IFCAP_TXRTLMT		0x1000000 /* hardware supports TX rate limiting */

#define IFCAP_HWCSUM_IPV6	(IFCAP_RXCSUM_IPV6 | IFCAP_TXCSUM_IPV6)

#define IFCAP_HWCSUM	(IFCAP_RXCSUM | IFCAP_TXCSUM)
#define	IFCAP_TSO	(IFCAP_TSO4 | IFCAP_TSO6)
#define	IFCAP_WOL	(IFCAP_WOL_UCAST | IFCAP_WOL_MCAST | IFCAP_WOL_MAGIC)
#define	IFCAP_TOE	(IFCAP_TOE4 | IFCAP_TOE6)

#define	IFCAP_CANTCHANGE	(IFCAP_NETMAP)

#define	IFQ_MAXLEN	50
#define	IFNET_SLOWHZ	1		/* granularity is 1 second */

/*
 * Message format for use in obtaining information about interfaces
 * from getkerninfo and the routing socket
 * For the new, extensible interface see struct if_msghdrl below.
 */
struct if_msghdr {
	u_short	ifm_msglen;	/* to skip over non-understood messages */
	u_char	ifm_version;	/* future binary compatibility */
	u_char	ifm_type;	/* message type */
	int	ifm_addrs;	/* like rtm_addrs */
	int	ifm_flags;	/* value of if_flags */
	u_short	ifm_index;	/* index for associated ifp */
	struct	if_data ifm_data;/* statistics and other data about if */
};

/*
 * The 'l' version shall be used by new interfaces, like NET_RT_IFLISTL.  It is
 * extensible after ifm_data_off or within ifm_data.  Both the if_msghdr and
 * if_data now have a member field detailing the struct length in addition to
 * the routing message length.  Macros are provided to find the start of
 * ifm_data and the start of the socket address strucutres immediately following
 * struct if_msghdrl given a pointer to struct if_msghdrl.
 */
#define	IF_MSGHDRL_IFM_DATA(_l) \
    (struct if_data *)((char *)(_l) + (_l)->ifm_data_off)
#define	IF_MSGHDRL_RTA(_l) \
    (void *)((uintptr_t)(_l) + (_l)->ifm_len)
struct if_msghdrl {
	u_short	ifm_msglen;	/* to skip over non-understood messages */
	u_char	ifm_version;	/* future binary compatibility */
	u_char	ifm_type;	/* message type */
	int	ifm_addrs;	/* like rtm_addrs */
	int	ifm_flags;	/* value of if_flags */
	u_short	ifm_index;	/* index for associated ifp */
	u_short _ifm_spare1;	/* spare space to grow if_index, see if_var.h */
	u_short	ifm_len;	/* length of if_msghdrl incl. if_data */
	u_short	ifm_data_off;	/* offset of if_data from beginning */
	struct	if_data ifm_data;/* statistics and other data about if */
};

/*
 * Message format for use in obtaining information about interface addresses
 * from getkerninfo and the routing socket
 * For the new, extensible interface see struct ifa_msghdrl below.
 */
struct ifa_msghdr {
	u_short	ifam_msglen;	/* to skip over non-understood messages */
	u_char	ifam_version;	/* future binary compatibility */
	u_char	ifam_type;	/* message type */
	int	ifam_addrs;	/* like rtm_addrs */
	int	ifam_flags;	/* value of ifa_flags */
	u_short	ifam_index;	/* index for associated ifp */
	int	ifam_metric;	/* value of ifa_ifp->if_metric */
};

/*
 * The 'l' version shall be used by new interfaces, like NET_RT_IFLISTL.  It is
 * extensible after ifam_metric or within ifam_data.  Both the ifa_msghdrl and
 * if_data now have a member field detailing the struct length in addition to
 * the routing message length.  Macros are provided to find the start of
 * ifm_data and the start of the socket address strucutres immediately following
 * struct ifa_msghdrl given a pointer to struct ifa_msghdrl.
 */
#define	IFA_MSGHDRL_IFAM_DATA(_l) \
    (struct if_data *)((char *)(_l) + (_l)->ifam_data_off)
#define	IFA_MSGHDRL_RTA(_l) \
    (void *)((uintptr_t)(_l) + (_l)->ifam_len)
struct ifa_msghdrl {
	u_short	ifam_msglen;	/* to skip over non-understood messages */
	u_char	ifam_version;	/* future binary compatibility */
	u_char	ifam_type;	/* message type */
	int	ifam_addrs;	/* like rtm_addrs */
	int	ifam_flags;	/* value of ifa_flags */
	u_short	ifam_index;	/* index for associated ifp */
	u_short _ifam_spare1;	/* spare space to grow if_index, see if_var.h */
	u_short	ifam_len;	/* length of ifa_msghdrl incl. if_data */
	u_short	ifam_data_off;	/* offset of if_data from beginning */
	int	ifam_metric;	/* value of ifa_ifp->if_metric */
	struct	if_data ifam_data;/* statistics and other data about if or
				 * address */
};

/*
 * Message format for use in obtaining information about multicast addresses
 * from the routing socket
 */
struct ifma_msghdr {
	u_short	ifmam_msglen;	/* to skip over non-understood messages */
	u_char	ifmam_version;	/* future binary compatibility */
	u_char	ifmam_type;	/* message type */
	int	ifmam_addrs;	/* like rtm_addrs */
	int	ifmam_flags;	/* value of ifa_flags */
	u_short	ifmam_index;	/* index for associated ifp */
};

/*
 * Message format announcing the arrival or departure of a network interface.
 */
struct if_announcemsghdr {
	u_short	ifan_msglen;	/* to skip over non-understood messages */
	u_char	ifan_version;	/* future binary compatibility */
	u_char	ifan_type;	/* message type */
	u_short	ifan_index;	/* index for associated ifp */
	char	ifan_name[IFNAMSIZ]; /* if name, e.g. "en0" */
	u_short	ifan_what;	/* what type of announcement */
};

#define	IFAN_ARRIVAL	0	/* interface arrival */
#define	IFAN_DEPARTURE	1	/* interface departure */

/*
 * Buffer with length to be used in SIOCGIFDESCR/SIOCSIFDESCR requests
 */
struct ifreq_buffer {
	size_t	length;
	void	*buffer;
};

/*
 * Interface request structure used for socket
 * ioctl's.  All interface ioctl's must have parameter
 * definitions which begin with ifr_name.  The
 * remainder may be interface specific.
 */
struct	ifreq {
	char	ifr_name[IFNAMSIZ];		/* if name, e.g. "en0" */
	union {
		struct	sockaddr ifru_addr;
		struct	sockaddr ifru_dstaddr;
		struct	sockaddr ifru_broadaddr;
		struct	ifreq_buffer ifru_buffer;
		short	ifru_flags[2];
		short	ifru_index;
		int	ifru_jid;
		int	ifru_metric;
		int	ifru_mtu;
		int	ifru_phys;
		int	ifru_media;
		caddr_t	ifru_data;
		int	ifru_cap[2];
		u_int	ifru_fib;
		u_char	ifru_vlan_pcp;
	} ifr_ifru;
#define	ifr_addr	ifr_ifru.ifru_addr	/* address */
#define	ifr_dstaddr	ifr_ifru.ifru_dstaddr	/* other end of p-to-p link */
#define	ifr_broadaddr	ifr_ifru.ifru_broadaddr	/* broadcast address */
#define	ifr_buffer	ifr_ifru.ifru_buffer	/* user supplied buffer with its length */
#define	ifr_flags	ifr_ifru.ifru_flags[0]	/* flags (low 16 bits) */
#define	ifr_flagshigh	ifr_ifru.ifru_flags[1]	/* flags (high 16 bits) */
#define	ifr_jid		ifr_ifru.ifru_jid	/* jail/vnet */
#define	ifr_metric	ifr_ifru.ifru_metric	/* metric */
#define	ifr_mtu		ifr_ifru.ifru_mtu	/* mtu */
#define ifr_phys	ifr_ifru.ifru_phys	/* physical wire */
#define ifr_media	ifr_ifru.ifru_media	/* physical media */
#define	ifr_data	ifr_ifru.ifru_data	/* for use by interface */
#define	ifr_reqcap	ifr_ifru.ifru_cap[0]	/* requested capabilities */
#define	ifr_curcap	ifr_ifru.ifru_cap[1]	/* current capabilities */
#define	ifr_index	ifr_ifru.ifru_index	/* interface index */
#define	ifr_fib		ifr_ifru.ifru_fib	/* interface fib */
#define	ifr_vlan_pcp	ifr_ifru.ifru_vlan_pcp	/* VLAN priority */
};

#define	_SIZEOF_ADDR_IFREQ(ifr) \
	((ifr).ifr_addr.sa_len > sizeof(struct sockaddr) ? \
	 (sizeof(struct ifreq) - sizeof(struct sockaddr) + \
	  (ifr).ifr_addr.sa_len) : sizeof(struct ifreq))

struct ifaliasreq {
	char	ifra_name[IFNAMSIZ];		/* if name, e.g. "en0" */
	struct	sockaddr ifra_addr;
	struct	sockaddr ifra_broadaddr;
	struct	sockaddr ifra_mask;
	int	ifra_vhid;
};

/* 9.x compat */
struct oifaliasreq {
	char	ifra_name[IFNAMSIZ];
	struct	sockaddr ifra_addr;
	struct	sockaddr ifra_broadaddr;
	struct	sockaddr ifra_mask;
};

struct ifmediareq {
	char	ifm_name[IFNAMSIZ];	/* if name, e.g. "en0" */
	int	ifm_current;		/* current media options */
	int	ifm_mask;		/* don't care mask */
	int	ifm_status;		/* media status */
	int	ifm_active;		/* active options */
	int	ifm_count;		/* # entries in ifm_ulist array */
	int	*ifm_ulist;		/* media words */
};

struct  ifdrv {
	char            ifd_name[IFNAMSIZ];     /* if name, e.g. "en0" */
	unsigned long   ifd_cmd;
	size_t          ifd_len;
	void            *ifd_data;
};

/* 
 * Structure used to retrieve aux status data from interfaces.
 * Kernel suppliers to this interface should respect the formatting
 * needed by ifconfig(8): each line starts with a TAB and ends with
 * a newline.  The canonical example to copy and paste is in if_tun.c.
 */

#define	IFSTATMAX	800		/* 10 lines of text */
struct ifstat {
	char	ifs_name[IFNAMSIZ];	/* if name, e.g. "en0" */
	char	ascii[IFSTATMAX + 1];
};

/*
 * Structure used in SIOCGIFCONF request.
 * Used to retrieve interface configuration
 * for machine (useful for programs which
 * must know all networks accessible).
 */
struct	ifconf {
	int	ifc_len;		/* size of associated buffer */
	union {
		caddr_t	ifcu_buf;
		struct	ifreq *ifcu_req;
	} ifc_ifcu;
#define	ifc_buf	ifc_ifcu.ifcu_buf	/* buffer address */
#define	ifc_req	ifc_ifcu.ifcu_req	/* array of structures returned */
};

/*
 * interface groups
 */

#define	IFG_ALL		"all"		/* group contains all interfaces */
/* XXX: will we implement this? */
#define	IFG_EGRESS	"egress"	/* if(s) default route(s) point to */

struct ifg_req {
	union {
		char			 ifgrqu_group[IFNAMSIZ];
		char			 ifgrqu_member[IFNAMSIZ];
	} ifgrq_ifgrqu;
#define	ifgrq_group	ifgrq_ifgrqu.ifgrqu_group
#define	ifgrq_member	ifgrq_ifgrqu.ifgrqu_member
};

/*
 * Used to lookup groups for an interface
 */
struct ifgroupreq {
	char	ifgr_name[IFNAMSIZ];
	u_int	ifgr_len;
	union {
		char	ifgru_group[IFNAMSIZ];
		struct	ifg_req *ifgru_groups;
	} ifgr_ifgru;
#define ifgr_group	ifgr_ifgru.ifgru_group
#define ifgr_groups	ifgr_ifgru.ifgru_groups
};

/*
 * Structure used to request i2c data
 * from interface transceivers.
 */
struct ifi2creq {
	uint8_t dev_addr;	/* i2c address (0xA0, 0xA2) */
	uint8_t offset;		/* read offset */
	uint8_t len;		/* read length */
	uint8_t spare0;
	uint32_t spare1;
	uint8_t data[8];	/* read buffer */
}; 

#endif /* __BSD_VISIBLE */

#ifdef _KERNEL
#ifdef MALLOC_DECLARE
MALLOC_DECLARE(M_IFADDR);
MALLOC_DECLARE(M_IFMADDR);
#endif
#endif

#ifndef _KERNEL
struct if_nameindex {
	unsigned int	if_index;	/* 1, 2, ... */
	char		*if_name;	/* null terminated name: "le0", ... */
};

__BEGIN_DECLS
void			 if_freenameindex(struct if_nameindex *);
char			*if_indextoname(unsigned int, char *);
struct if_nameindex	*if_nameindex(void);
unsigned int		 if_nametoindex(const char *);
__END_DECLS
#endif
#endif /* !_NET_IF_H_ */