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if.h revision 1.43
      1 /*	$NetBSD: if.h,v 1.43 1999/12/13 15:17:19 itojun Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1982, 1986, 1989, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  *
     35  *	@(#)if.h	8.3 (Berkeley) 2/9/95
     36  */
     37 
     38 #ifndef _NET_IF_H_
     39 #define _NET_IF_H_
     40 
     41 #if !defined(_XOPEN_SOURCE)
     42 
     43 #include <sys/queue.h>
     44 
     45 /*
     46  * Structures defining a network interface, providing a packet
     47  * transport mechanism (ala level 0 of the PUP protocols).
     48  *
     49  * Each interface accepts output datagrams of a specified maximum
     50  * length, and provides higher level routines with input datagrams
     51  * received from its medium.
     52  *
     53  * Output occurs when the routine if_output is called, with four parameters:
     54  *	(*ifp->if_output)(ifp, m, dst, rt)
     55  * Here m is the mbuf chain to be sent and dst is the destination address.
     56  * The output routine encapsulates the supplied datagram if necessary,
     57  * and then transmits it on its medium.
     58  *
     59  * On input, each interface unwraps the data received by it, and either
     60  * places it on the input queue of a internetwork datagram routine
     61  * and posts the associated software interrupt, or passes the datagram to a raw
     62  * packet input routine.
     63  *
     64  * Routines exist for locating interfaces by their addresses
     65  * or for locating a interface on a certain network, as well as more general
     66  * routing and gateway routines maintaining information used to locate
     67  * interfaces.  These routines live in the files if.c and route.c
     68  */
     69 /*  XXX fast fix for SNMP, going away soon */
     70 #include <sys/time.h>
     71 
     72 #if defined(_KERNEL) && !defined(_LKM)
     73 #include "opt_compat_netbsd.h"
     74 #endif
     75 
     76 struct mbuf;
     77 struct proc;
     78 struct rtentry;
     79 struct socket;
     80 struct ether_header;
     81 
     82 /*
     83  * Structure defining statistics and other data kept regarding a network
     84  * interface.
     85  */
     86 struct	if_data {
     87 	/* generic interface information */
     88 	u_char	ifi_type;		/* ethernet, tokenring, etc. */
     89 	u_char	ifi_addrlen;		/* media address length */
     90 	u_char	ifi_hdrlen;		/* media header length */
     91 	u_quad_t ifi_mtu;		/* maximum transmission unit */
     92 	u_quad_t ifi_metric;		/* routing metric (external only) */
     93 	u_quad_t ifi_baudrate;		/* linespeed */
     94 	/* volatile statistics */
     95 	u_quad_t ifi_ipackets;		/* packets received on interface */
     96 	u_quad_t ifi_ierrors;		/* input errors on interface */
     97 	u_quad_t ifi_opackets;		/* packets sent on interface */
     98 	u_quad_t ifi_oerrors;		/* output errors on interface */
     99 	u_quad_t ifi_collisions;	/* collisions on csma interfaces */
    100 	u_quad_t ifi_ibytes;		/* total number of octets received */
    101 	u_quad_t ifi_obytes;		/* total number of octets sent */
    102 	u_quad_t ifi_imcasts;		/* packets received via multicast */
    103 	u_quad_t ifi_omcasts;		/* packets sent via multicast */
    104 	u_quad_t ifi_iqdrops;		/* dropped on input, this interface */
    105 	u_quad_t ifi_noproto;		/* destined for unsupported protocol */
    106 	struct	timeval ifi_lastchange;	/* last updated */
    107 };
    108 
    109 #ifdef COMPAT_14
    110 /* Pre-1.5 if_data struct */
    111 struct	if_data14 {
    112 	/* generic interface information */
    113 	u_char	ifi_type;		/* ethernet, tokenring, etc. */
    114 	u_char	ifi_addrlen;		/* media address length */
    115 	u_char	ifi_hdrlen;		/* media header length */
    116 	u_long	ifi_mtu;		/* maximum transmission unit */
    117 	u_long	ifi_metric;		/* routing metric (external only) */
    118 	u_long	ifi_baudrate;		/* linespeed */
    119 	/* volatile statistics */
    120 	u_long	ifi_ipackets;		/* packets received on interface */
    121 	u_long	ifi_ierrors;		/* input errors on interface */
    122 	u_long	ifi_opackets;		/* packets sent on interface */
    123 	u_long	ifi_oerrors;		/* output errors on interface */
    124 	u_long	ifi_collisions;		/* collisions on csma interfaces */
    125 	u_long	ifi_ibytes;		/* total number of octets received */
    126 	u_long	ifi_obytes;		/* total number of octets sent */
    127 	u_long	ifi_imcasts;		/* packets received via multicast */
    128 	u_long	ifi_omcasts;		/* packets sent via multicast */
    129 	u_long	ifi_iqdrops;		/* dropped on input, this interface */
    130 	u_long	ifi_noproto;		/* destined for unsupported protocol */
    131 	struct	timeval ifi_lastchange;	/* last updated */
    132 };
    133 #endif
    134 
    135 /*
    136  * Structure defining a queue for a network interface.
    137  *
    138  * (Would like to call this struct ``if'', but C isn't PL/1.)
    139  */
    140 TAILQ_HEAD(ifnet_head, ifnet);		/* the actual queue head */
    141 
    142 /*
    143  * Length of interface external name, including terminating '\0'.
    144  * Note: this is the same size as a generic device's external name.
    145  */
    146 #define	IFNAMSIZ	16
    147 #define	IF_NAMESIZE	IFNAMSIZ
    148 
    149 struct ifnet {				/* and the entries */
    150 	void	*if_softc;		/* lower-level data for this if */
    151 	TAILQ_ENTRY(ifnet) if_list;	/* all struct ifnets are chained */
    152 	TAILQ_HEAD(, ifaddr) if_addrlist; /* linked list of addresses per if */
    153 	char	if_xname[IFNAMSIZ];	/* external name (name + unit) */
    154 	int	if_pcount;		/* number of promiscuous listeners */
    155 	caddr_t	if_bpf;			/* packet filter structure */
    156 	u_short	if_index;		/* numeric abbreviation for this if */
    157 	short	if_timer;		/* time 'til if_watchdog called */
    158 	short	if_flags;		/* up/down, broadcast, etc. */
    159 	short	if__pad1;		/* be nice to m68k ports */
    160 	struct	if_data if_data;	/* statistics and other data about if */
    161 /* procedure handles */
    162 	int	(*if_output)		/* output routine (enqueue) */
    163 		__P((struct ifnet *, struct mbuf *, struct sockaddr *,
    164 		     struct rtentry *));
    165 	void	(*if_input)		/* input routine (from h/w driver) */
    166 		__P((struct ifnet *, struct mbuf *));
    167 	void	(*if_start)		/* initiate output routine */
    168 		__P((struct ifnet *));
    169 	int	(*if_ioctl)		/* ioctl routine */
    170 		__P((struct ifnet *, u_long, caddr_t));
    171 	int	(*if_reset)		/* XXX bus reset routine */
    172 		__P((struct ifnet *));
    173 	void	(*if_watchdog)		/* timer routine */
    174 		__P((struct ifnet *));
    175 	void	(*if_drain)		/* routine to release resources */
    176 		__P((struct ifnet *));
    177 	struct	ifqueue {
    178 		struct	mbuf *ifq_head;
    179 		struct	mbuf *ifq_tail;
    180 		int	ifq_len;
    181 		int	ifq_maxlen;
    182 		int	ifq_drops;
    183 	} if_snd;			/* output queue */
    184 	struct	sockaddr_dl *if_sadl;	/* pointer to our sockaddr_dl */
    185 	u_int8_t *if_broadcastaddr;	/* linklevel broadcast bytestring */
    186 	struct ifprefix *if_prefixlist; /* linked list of prefixes per if */
    187 };
    188 #define	if_mtu		if_data.ifi_mtu
    189 #define	if_type		if_data.ifi_type
    190 #define	if_addrlen	if_data.ifi_addrlen
    191 #define	if_hdrlen	if_data.ifi_hdrlen
    192 #define	if_metric	if_data.ifi_metric
    193 #define	if_baudrate	if_data.ifi_baudrate
    194 #define	if_ipackets	if_data.ifi_ipackets
    195 #define	if_ierrors	if_data.ifi_ierrors
    196 #define	if_opackets	if_data.ifi_opackets
    197 #define	if_oerrors	if_data.ifi_oerrors
    198 #define	if_collisions	if_data.ifi_collisions
    199 #define	if_ibytes	if_data.ifi_ibytes
    200 #define	if_obytes	if_data.ifi_obytes
    201 #define	if_imcasts	if_data.ifi_imcasts
    202 #define	if_omcasts	if_data.ifi_omcasts
    203 #define	if_iqdrops	if_data.ifi_iqdrops
    204 #define	if_noproto	if_data.ifi_noproto
    205 #define	if_lastchange	if_data.ifi_lastchange
    206 
    207 #define	IFF_UP		0x1		/* interface is up */
    208 #define	IFF_BROADCAST	0x2		/* broadcast address valid */
    209 #define	IFF_DEBUG	0x4		/* turn on debugging */
    210 #define	IFF_LOOPBACK	0x8		/* is a loopback net */
    211 #define	IFF_POINTOPOINT	0x10		/* interface is point-to-point link */
    212 #define	IFF_NOTRAILERS	0x20		/* avoid use of trailers */
    213 #define	IFF_RUNNING	0x40		/* resources allocated */
    214 #define	IFF_NOARP	0x80		/* no address resolution protocol */
    215 #define	IFF_PROMISC	0x100		/* receive all packets */
    216 #define	IFF_ALLMULTI	0x200		/* receive all multicast packets */
    217 #define	IFF_OACTIVE	0x400		/* transmission in progress */
    218 #define	IFF_SIMPLEX	0x800		/* can't hear own transmissions */
    219 #define	IFF_LINK0	0x1000		/* per link layer defined bit */
    220 #define	IFF_LINK1	0x2000		/* per link layer defined bit */
    221 #define	IFF_LINK2	0x4000		/* per link layer defined bit */
    222 #define	IFF_MULTICAST	0x8000		/* supports multicast */
    223 
    224 /* flags set internally only: */
    225 #define	IFF_CANTCHANGE \
    226 	(IFF_BROADCAST|IFF_POINTOPOINT|IFF_RUNNING|IFF_OACTIVE|\
    227 	    IFF_SIMPLEX|IFF_MULTICAST|IFF_ALLMULTI)
    228 
    229 /*
    230  * Output queues (ifp->if_snd) and internetwork datagram level (pup level 1)
    231  * input routines have queues of messages stored on ifqueue structures
    232  * (defined above).  Entries are added to and deleted from these structures
    233  * by these macros, which should be called with ipl raised to splimp().
    234  */
    235 #define	IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
    236 #define	IF_DROP(ifq)		((ifq)->ifq_drops++)
    237 #define	IF_ENQUEUE(ifq, m) { \
    238 	(m)->m_nextpkt = 0; \
    239 	if ((ifq)->ifq_tail == 0) \
    240 		(ifq)->ifq_head = m; \
    241 	else \
    242 		(ifq)->ifq_tail->m_nextpkt = m; \
    243 	(ifq)->ifq_tail = m; \
    244 	(ifq)->ifq_len++; \
    245 }
    246 #define	IF_PREPEND(ifq, m) { \
    247 	(m)->m_nextpkt = (ifq)->ifq_head; \
    248 	if ((ifq)->ifq_tail == 0) \
    249 		(ifq)->ifq_tail = (m); \
    250 	(ifq)->ifq_head = (m); \
    251 	(ifq)->ifq_len++; \
    252 }
    253 #define	IF_DEQUEUE(ifq, m) { \
    254 	(m) = (ifq)->ifq_head; \
    255 	if (m) { \
    256 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) \
    257 			(ifq)->ifq_tail = 0; \
    258 		(m)->m_nextpkt = 0; \
    259 		(ifq)->ifq_len--; \
    260 	} \
    261 }
    262 
    263 #define	IFQ_MAXLEN	50
    264 #define	IFNET_SLOWHZ	1		/* granularity is 1 second */
    265 
    266 /*
    267  * Structure defining statistics and other data kept regarding an address
    268  * on a network interface.
    269  */
    270 struct ifaddr_data {
    271 	int64_t	ifad_inbytes;
    272 	int64_t	ifad_outbytes;
    273 };
    274 
    275 /*
    276  * The ifaddr structure contains information about one address
    277  * of an interface.  They are maintained by the different address families,
    278  * are allocated and attached when an address is set, and are linked
    279  * together so all addresses for an interface can be located.
    280  */
    281 struct ifaddr {
    282 	struct	sockaddr *ifa_addr;	/* address of interface */
    283 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
    284 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
    285 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
    286 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
    287 	TAILQ_ENTRY(ifaddr) ifa_list;	/* list of addresses for interface */
    288 	struct	ifaddr_data	ifa_data;	/* statistics on the address */
    289 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
    290 		    __P((int, struct rtentry *, struct sockaddr *));
    291 	u_int	ifa_flags;		/* mostly rt_flags for cloning */
    292 	int	ifa_refcnt;		/* count of references */
    293 	int	ifa_metric;		/* cost of going out this interface */
    294 };
    295 #define	IFA_ROUTE	RTF_UP		/* route installed */
    296 
    297 /*
    298  * The prefix structure contains information about one prefix
    299  * of an interface.  They are maintained by the different address families,
    300  * are allocated and attached when an prefix or an address is set,
    301  * and are linked together so all prfefixes for an interface can be located.
    302  */
    303 struct ifprefix {
    304 	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
    305 	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
    306 	struct ifprefix *ifpr_next;
    307 	u_char	ifpr_plen;		/* prefix length in bits */
    308 	u_char	ifpr_type;		/* protocol dependent prefix type */
    309 };
    310 
    311 /*
    312  * Message format for use in obtaining information about interfaces
    313  * from sysctl and the routing socket.
    314  */
    315 struct if_msghdr {
    316 	u_short	ifm_msglen;	/* to skip over non-understood messages */
    317 	u_char	ifm_version;	/* future binary compatability */
    318 	u_char	ifm_type;	/* message type */
    319 	int	ifm_addrs;	/* like rtm_addrs */
    320 	int	ifm_flags;	/* value of if_flags */
    321 	u_short	ifm_index;	/* index for associated ifp */
    322 	struct	if_data ifm_data;/* statistics and other data about if */
    323 };
    324 
    325 #ifdef COMPAT_14
    326 /* pre-1.5 if_msghdr (ifm_data changed) */
    327 struct if_msghdr14 {
    328 	u_short	ifm_msglen;	/* to skip over non-understood messages */
    329 	u_char	ifm_version;	/* future binary compatability */
    330 	u_char	ifm_type;	/* message type */
    331 	int	ifm_addrs;	/* like rtm_addrs */
    332 	int	ifm_flags;	/* value of if_flags */
    333 	u_short	ifm_index;	/* index for associated ifp */
    334 	struct	if_data14 ifm_data; /* statistics and other data about if */
    335 };
    336 #endif
    337 
    338 /*
    339  * Message format for use in obtaining information about interface addresses
    340  * from sysctl and the routing socket.
    341  */
    342 struct ifa_msghdr {
    343 	u_short	ifam_msglen;	/* to skip over non-understood messages */
    344 	u_char	ifam_version;	/* future binary compatability */
    345 	u_char	ifam_type;	/* message type */
    346 	int	ifam_addrs;	/* like rtm_addrs */
    347 	int	ifam_flags;	/* value of ifa_flags */
    348 	u_short	ifam_index;	/* index for associated ifp */
    349 	int	ifam_metric;	/* value of ifa_metric */
    350 };
    351 
    352 /*
    353  * Interface request structure used for socket
    354  * ioctl's.  All interface ioctl's must have parameter
    355  * definitions which begin with ifr_name.  The
    356  * remainder may be interface specific.
    357  */
    358 struct	ifreq {
    359 	char	ifr_name[IFNAMSIZ];		/* if name, e.g. "en0" */
    360 	union {
    361 		struct	sockaddr ifru_addr;
    362 		struct	sockaddr ifru_dstaddr;
    363 		struct	sockaddr ifru_broadaddr;
    364 		short	ifru_flags;
    365 		int	ifru_metric;
    366 		int	ifru_mtu;
    367 		u_int	ifru_value;
    368 		caddr_t	ifru_data;
    369 	} ifr_ifru;
    370 #define	ifr_addr	ifr_ifru.ifru_addr	/* address */
    371 #define	ifr_dstaddr	ifr_ifru.ifru_dstaddr	/* other end of p-to-p link */
    372 #define	ifr_broadaddr	ifr_ifru.ifru_broadaddr	/* broadcast address */
    373 #define	ifr_flags	ifr_ifru.ifru_flags	/* flags */
    374 #define	ifr_metric	ifr_ifru.ifru_metric	/* metric */
    375 #define	ifr_mtu		ifr_ifru.ifru_mtu	/* mtu */
    376 #define	ifr_value	ifr_ifru.ifru_value	/* generic value */
    377 #define	ifr_media	ifr_ifru.ifru_metric	/* media options (overload) */
    378 #define	ifr_data	ifr_ifru.ifru_data	/* for use by interface */
    379 };
    380 
    381 struct ifaliasreq {
    382 	char	ifra_name[IFNAMSIZ];		/* if name, e.g. "en0" */
    383 	struct	sockaddr ifra_addr;
    384 	struct	sockaddr ifra_dstaddr;
    385 #define	ifra_broadaddr	ifra_dstaddr
    386 	struct	sockaddr ifra_mask;
    387 };
    388 
    389 struct ifmediareq {
    390 	char	ifm_name[IFNAMSIZ];		/* if name, e.g. "en0" */
    391 	int	ifm_current;			/* current media options */
    392 	int	ifm_mask;			/* don't care mask */
    393 	int	ifm_status;			/* media status */
    394 	int	ifm_active;			/* active options */
    395 	int	ifm_count;			/* # entries in ifm_ulist
    396 						   array */
    397 	int	*ifm_ulist;			/* media words */
    398 };
    399 
    400 
    401 struct  ifdrv {
    402 	char		ifd_name[IFNAMSIZ];	/* if name, e.g. "en0" */
    403 	unsigned long	ifd_cmd;
    404 	size_t		ifd_len;
    405 	void		*ifd_data;
    406 };
    407 
    408 /*
    409  * Structure used in SIOCGIFCONF request.
    410  * Used to retrieve interface configuration
    411  * for machine (useful for programs which
    412  * must know all networks accessible).
    413  */
    414 struct	ifconf {
    415 	int	ifc_len;		/* size of associated buffer */
    416 	union {
    417 		caddr_t	ifcu_buf;
    418 		struct	ifreq *ifcu_req;
    419 	} ifc_ifcu;
    420 #define	ifc_buf	ifc_ifcu.ifcu_buf	/* buffer address */
    421 #define	ifc_req	ifc_ifcu.ifcu_req	/* array of structures returned */
    422 };
    423 
    424 /*
    425  * Structure for SIOC[AGD]LIFADDR
    426  */
    427 struct if_laddrreq {
    428 	char iflr_name[IFNAMSIZ];
    429 	unsigned int flags;
    430 #define IFLR_PREFIX	0x8000	/* in: prefix given  out: kernel fills id */
    431 	unsigned int prefixlen;		/* in/out */
    432 	struct sockaddr_storage addr;	/* in/out */
    433 	struct sockaddr_storage dstaddr; /* out */
    434 };
    435 
    436 #include <net/if_arp.h>
    437 
    438 #endif /* !_XOPEN_SOURCE */
    439 
    440 #ifdef _KERNEL
    441 #define	IFAFREE(ifa) \
    442 	if ((ifa)->ifa_refcnt <= 0) \
    443 		ifafree(ifa); \
    444 	else \
    445 		(ifa)->ifa_refcnt--;
    446 
    447 struct ifnet_head ifnet;
    448 struct ifnet **ifindex2ifnet;
    449 #if 0
    450 struct ifnet loif[];
    451 #endif
    452 int if_index;
    453 
    454 void	ether_ifattach __P((struct ifnet *, const u_int8_t *));
    455 char	*ether_sprintf __P((const u_char *));
    456 
    457 void	if_attach __P((struct ifnet *));
    458 void	if_down __P((struct ifnet *));
    459 void	if_qflush __P((struct ifqueue *));
    460 void	if_slowtimo __P((void *));
    461 void	if_up __P((struct ifnet *));
    462 int	ifconf __P((u_long, caddr_t));
    463 void	ifinit __P((void));
    464 int	ifioctl __P((struct socket *, u_long, caddr_t, struct proc *));
    465 int	ifpromisc __P((struct ifnet *, int));
    466 struct	ifnet *ifunit __P((const char *));
    467 struct  ifnet *if_withname __P((struct sockaddr *));
    468 
    469 struct	ifaddr *ifa_ifwithaddr __P((struct sockaddr *));
    470 struct	ifaddr *ifa_ifwithaf __P((int));
    471 struct	ifaddr *ifa_ifwithdstaddr __P((struct sockaddr *));
    472 struct	ifaddr *ifa_ifwithnet __P((struct sockaddr *));
    473 struct	ifaddr *ifa_ifwithladdr __P((struct sockaddr *));
    474 struct	ifaddr *ifa_ifwithroute __P((int, struct sockaddr *,
    475 					struct sockaddr *));
    476 struct	ifaddr *ifaof_ifpforaddr __P((struct sockaddr *, struct ifnet *));
    477 void	ifafree __P((struct ifaddr *));
    478 void	link_rtrequest __P((int, struct rtentry *, struct sockaddr *));
    479 
    480 int	loioctl __P((struct ifnet *, u_long, caddr_t));
    481 void	loopattach __P((int));
    482 int	looutput __P((struct ifnet *,
    483 	   struct mbuf *, struct sockaddr *, struct rtentry *));
    484 void	lortrequest __P((int, struct rtentry *, struct sockaddr *));
    485 #else
    486 struct if_nameindex {
    487 	unsigned int	if_index;	/* 1, 2, ... */
    488 	char		*if_name;	/* null terminated name: "le0", ... */
    489 };
    490 
    491 #include <sys/cdefs.h>
    492 __BEGIN_DECLS
    493 unsigned int if_nametoindex __P((const char *));
    494 char *	if_indextoname __P((unsigned int, char *));
    495 struct	if_nameindex * if_nameindex __P((void));
    496 void	if_freenameindex __P((struct if_nameindex *));
    497 __END_DECLS
    498 #endif /* _KERNEL */
    499 #endif /* !_NET_IF_H_ */
    500