/*
 * 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.
 * 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 1.107 2006/06/19 22:20:44 mlaier Exp $
 */
 
/*
 * $Id$
 */

#ifndef	_NET_IF_VAR_H_
#define	_NET_IF_VAR_H_

/*
 * 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 three 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 an internetwork datagram routine
 * and posts the associated software interrupt, or passes the datagram to a raw
 * packet input routine.
 *
 * Routines exist for locating interfaces by their addresses
 * or for locating an 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;
#ifndef __rtems__
struct	thread;
#endif
struct	rtentry;
struct	rt_addrinfo;
struct	socket;
struct	ether_header;
#ifndef __rtems__
struct	carp_if;
#endif

#include <sys/queue.h>		/* get TAILQ macros */

/*
 * 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;
};

/*
 * Structure defining a network interface.
 *
 * (Would like to call this struct ``if'', but C isn't PL/1.)
 */
struct ifnet {
	void	*if_softc;		/* pointer to driver state */
	char	*if_name;		/* name, e.g. ``en'' or ``lo'' */
	struct	ifnet *if_next;		/* all struct ifnets are chained */
	struct	ifaddr *if_addrlist;	/* linked list of addresses per if */
        int	if_pcount;		/* number of promiscuous listeners */
	struct	bpf_if *if_bpf;		/* packet filter structure */
	u_short	if_index;		/* numeric abbreviation for this if  */
	short	if_unit;		/* sub-unit for lower level driver */
	short	if_timer;		/* time 'til if_watchdog called */
	int	if_flags;		/* up/down, broadcast, etc. */
	void	*if_linkmib;		/* link-type-specific MIB data */
	size_t	if_linkmiblen;		/* length of above data */
	struct	if_data if_data;
/* procedure handles */
	int	(*if_output)		/* output routine (enqueue) */
		(struct ifnet *, struct mbuf *, struct sockaddr *,
		     struct rtentry *);
	void	(*if_start)		/* initiate output routine */
		(struct ifnet *);
	int	(*if_ioctl)		/* ioctl routine */
		(struct ifnet *, ioctl_command_t, caddr_t);
	void	(*if_watchdog)		/* timer routine */
		(struct ifnet *);
	int	(*if_poll_recv)		/* polled receive routine */
		(struct ifnet *, int *);
	int	(*if_poll_xmit)		/* polled transmit routine */
		(struct ifnet *, int *);
	void	(*if_poll_intren)	/* polled interrupt reenable routine */
		(struct ifnet *);
	void	(*if_poll_slowinput)	/* input routine for slow devices */
		(struct ifnet *, struct mbuf *);
	void	(*if_init)		/* Init routine */
		(void *);
	int	(*if_tap)		/* Packet filter routine */
		(struct ifnet *, struct ether_header *, struct mbuf *);
	struct	ifqueue if_snd;		/* output queue */
	struct	ifqueue *if_poll_slowq;	/* input queue for slow devices */
};

typedef void if_init_f_t(void *);

/*
 * XXX These aliases are terribly dangerous because they could apply
 * to anything.
 */
#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_baudrate	if_data.ifi_baudrate
#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, (struct rtentry *)NULL)

/*
 * 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_ENQUEUE(ifq, m) do {		 			\
	(m)->m_nextpkt = NULL; \
	if ((ifq)->ifq_tail == NULL) \
		(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 == NULL) \
		(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) == NULL) \
			(ifq)->ifq_tail = NULL; \
		(m)->m_nextpkt = NULL; \
		(ifq)->ifq_len--; \
	} \
} while (0)

/*
 * 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	ifnet *ifa_ifp;		/* back-pointer to interface */
	struct	ifaddr *ifa_next;	/* next address for interface */
	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
		(int, struct rtentry *, struct sockaddr *);
	u_short	ifa_flags;		/* mostly rt_flags for cloning */
	u_int	ifa_refcnt;		/* references to this structure */
	int	ifa_metric;		/* cost of going out this interface */
	int (*ifa_claim_addr)		/* check if an addr goes to this if */
		(struct ifaddr *, struct sockaddr *);

};
#define	IFA_ROUTE	RTF_UP		/* route installed */

#ifdef _KERNEL
#define	IFAFREE(ifa) \
	if ((ifa)->ifa_refcnt <= 0) \
		ifafree(ifa); \
	else \
		(ifa)->ifa_refcnt--;

extern struct	ifnet	*ifnet;
extern int	ifqmaxlen;
extern struct	ifnet	loif[];
extern int	if_index;
extern struct	ifaddr	**ifnet_addrs;

void	if_attach(struct ifnet *);
void	if_down(struct ifnet *);
void	if_up(struct ifnet *);
/*void	ifinit(void);*/ /* declared in systm.h for main() */
int	ifioctl(struct socket *, u_long, caddr_t, struct proc *);
int	ifpromisc(struct ifnet *, int);

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 *);

#endif /* _KERNEL */

#endif /* !_NET_IF_VAR_H_ */