/*	$NetBSD: if_arcsubr.c,v 1.1 1995/02/23 07:19:51 glass Exp $	*/

/*
 * Copyright (c) 1994, 1995 Ignatios Souvatzis
 * Copyright (c) 1982, 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: NetBSD: if_ethersubr.c,v 1.9 1994/06/29 06:36:11 cgd Exp
 *       @(#)if_ethersubr.c	8.1 (Berkeley) 6/10/93
 *
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/errno.h>

#include <machine/cpu.h>

#include <net/if.h>
#include <net/netisr.h>
#include <net/route.h>
#include <net/if_dl.h>
#include <net/if_types.h>

#ifdef INET
#include <netinet/in.h>
#include <netinet/in_var.h>
#endif
#include <netinet/if_arc.h>

u_char	arcbroadcastaddr = 0;
extern	struct ifnet loif;

#define senderr(e) { error = (e); goto bad;}

#define SIN(s) ((struct sockaddr_in *)s)

/*
 * ARCnet output routine.
 * Encapsulate a packet of type family for the local net.
 * Assumes that ifp is actually pointer to arccom structure.
 */
int
arc_output(ifp, m0, dst, rt0)
	register struct ifnet *ifp;
	struct mbuf *m0;
	struct sockaddr *dst;
	struct rtentry *rt0;
{
	int s, error = 0;
	u_char atype, adst;
	register struct mbuf *m = m0;
	register struct rtentry *rt;
	struct mbuf *mcopy = (struct mbuf *)0;
	register struct arc_header *ah;
	int off, len = m->m_pkthdr.len;
	struct arccom *ac = (struct arccom *)ifp;

	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
		senderr(ENETDOWN);
	ifp->if_lastchange = time;
	if (rt = rt0) {
		if ((rt->rt_flags & RTF_UP) == 0) {
			if (rt0 = rt = rtalloc1(dst, 1))
				rt->rt_refcnt--;
			else 
				senderr(EHOSTUNREACH);
		}
		if (rt->rt_flags & RTF_GATEWAY) {
			if (rt->rt_gwroute == 0)
				goto lookup;
			if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) {
				rtfree(rt); rt = rt0;
			lookup: rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1);
				if ((rt = rt->rt_gwroute) == 0)
					senderr(EHOSTUNREACH);
			}
		}
		if (rt->rt_flags & RTF_REJECT)
			if (rt->rt_rmx.rmx_expire == 0 ||
			    time.tv_sec < rt->rt_rmx.rmx_expire)
				senderr(rt == rt0 ? EHOSTDOWN : EHOSTUNREACH);
	}
	switch (dst->sa_family) {

#ifdef INET
	case AF_INET:

		/*
		 * For now, use the simple IP addr -> ARCnet addr mapping
		 */
		if (m->m_flags & M_BCAST) 
			adst = arcbroadcastaddr; /* ARCnet broadcast address */
		else
			adst = ntohl(SIN(dst)->sin_addr.s_addr) & 0xFF;

		/* If broadcasting on a simplex interface, loopback a copy */
		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX))
			mcopy = m_copy(m, 0, (int)M_COPYALL);
		off = m->m_pkthdr.len - m->m_len;
		atype = ARCTYPE_IP_OLD;
		break;
#endif
	case AF_UNSPEC:
		ah = (struct arc_header *)dst->sa_data;
 		adst = ah->arc_dhost;
		atype = ah->arc_type;
		break;

	default:
		printf("%s%d: can't handle af%d\n", ifp->if_name, ifp->if_unit,
			dst->sa_family);
		senderr(EAFNOSUPPORT);
	}


	if (mcopy)
		(void) looutput(ifp, mcopy, dst, rt);
	/*
	 * Add local net header.  If no space in first mbuf,
	 * allocate another.
	 * 
	 * For ARCnet, this is just symbolic. The header changes
	 * form and position on its way into the hardware and out of
	 * the wire.  At this point, it contains source, destination and
	 * packet type.
	 */
	M_PREPEND(m, ARC_HDRLEN, M_DONTWAIT);
	if (m == 0)
		senderr(ENOBUFS);
	ah = mtod(m, struct arc_header *);
	ah->arc_type = atype;
	ah->arc_dhost= adst;
	ah->arc_shost= ac->ac_anaddr;
	s = splimp();
	/*
	 * Queue message on interface, and start output if interface
	 * not yet active.
	 */
	if (IF_QFULL(&ifp->if_snd)) {
		IF_DROP(&ifp->if_snd);
		splx(s);
		senderr(ENOBUFS);
	}
	IF_ENQUEUE(&ifp->if_snd, m);
	if ((ifp->if_flags & IFF_OACTIVE) == 0)
		(*ifp->if_start)(ifp);
	splx(s);
	
	ifp->if_obytes += len + ARC_HDRLEN;
	return (error);

bad:
	if (m)
		m_freem(m);
	return (error);
}

/*
 * Process a received Arcnet packet;
 * the packet is in the mbuf chain m without
 * the ARCnet header, which is provided separately.
 */
void
arc_input(ifp, ah, m)
	struct ifnet *ifp;
	register struct arc_header *ah;
	struct mbuf *m;
{
	register struct ifqueue *inq;
	u_char atype;
	int s;

	if ((ifp->if_flags & IFF_UP) == 0) {
		m_freem(m);
		return;
	}
	ifp->if_lastchange = time;
	ifp->if_ibytes += m->m_pkthdr.len + sizeof (*ah);

	if (arcbroadcastaddr == ah->arc_dhost) {
		m->m_flags |= M_BCAST;
		ifp->if_imcasts++;
	}

	atype = ah->arc_type;
	switch (atype) {
#ifdef INET
	case ARCTYPE_IP_OLD:
		schednetisr(NETISR_IP);
		inq = &ipintrq;
		break;
#endif
	default:
		m_freem(m);
		return;
	}

	s = splimp();
	if (IF_QFULL(inq)) {
		IF_DROP(inq);
		m_freem(m);
	} else
		IF_ENQUEUE(inq, m);
	splx(s);
}

/*
 * Convert Arcnet address to printable (loggable) representation.
 */
static char digits[] = "0123456789abcdef";
char *
arc_sprintf(ap)
	register u_char *ap;
{
	static char arcbuf[3];
	register char *cp = arcbuf;

	*cp++ = digits[*ap >> 4];
	*cp++ = digits[*ap++ & 0xf];
	*cp   = 0;
	return (arcbuf);
}

/*
 * Perform common duties while attaching to interface list
 */
void
arc_ifattach(ifp)
	register struct ifnet *ifp;
{
	register struct ifaddr *ifa;
	register struct sockaddr_dl *sdl;

	ifp->if_type = IFT_ARCNET;
	ifp->if_addrlen = 1;
	ifp->if_hdrlen = ARC_HDRLEN;
	ifp->if_mtu = ARCMTU;
	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
		if ((sdl = (struct sockaddr_dl *)ifa->ifa_addr) &&
		    sdl->sdl_family == AF_LINK) {
			sdl->sdl_type = IFT_ARCNET;
			sdl->sdl_alen = ifp->if_addrlen;
			bcopy((caddr_t)&((struct arccom *)ifp)->ac_anaddr,
			      LLADDR(sdl), ifp->if_addrlen);
			break;
		}
}