/*      $OpenBSD: if_atmsubr.c,v 1.12 2000/02/07 06:09:08 itojun Exp $       */

/*
 *
 * Copyright (c) 1996 Charles D. Cranor and Washington University.
 * 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 Charles D. Cranor and 
 *	Washington University.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

/*
%%% portions-copyright-nrl-95
Portions of this software are Copyright 1995-1998 by Randall Atkinson,
Ronald Lee, Daniel McDonald, Bao Phan, and Chris Winters. All Rights
Reserved. All rights under this copyright have been assigned to the US
Naval Research Laboratory (NRL). The NRL Copyright Notice and License
Agreement Version 1.1 (January 17, 1995) applies to these portions of the
software.
You should have received a copy of the license with this software. If you
didn't get a copy, you may request one from <license@ipv6.nrl.navy.mil>.
*/

/*
 * if_atmsubr.c
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/errno.h>
#include <sys/syslog.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>
#include <net/if_atm.h>

#include <netinet/in.h>
#include <netinet/if_atm.h>
#include <netinet/if_ether.h> /* XXX: for ETHERTYPE_* */
#ifdef INET
#include <netinet/in_var.h>
#endif
#ifdef NATM
#include <netnatm/natm.h>
#endif
#ifdef INET6
#include <netinet6/in6_var.h>
#endif /* INET6 */

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

/*
 * atm_output: ATM output routine
 *   inputs:
 *     "ifp" = ATM interface to output to
 *     "m0" = the packet to output
 *     "dst" = the sockaddr to send to (either IP addr, or raw VPI/VCI)
 *     "rt0" = the route to use
 *   returns: error code   [0 == ok]
 *
 *   note: special semantic: if (dst == NULL) then we assume "m" already
 *		has an atm_pseudohdr on it and just send it directly.
 *		[for native mode ATM output]   if dst is null, then
 *		rt0 must also be NULL.
 */

int
atm_output(ifp, m0, dst, rt0)
	register struct ifnet *ifp;
	struct mbuf *m0;
	struct sockaddr *dst;
	struct rtentry *rt0;
{
	u_int16_t etype = 0;			/* if using LLC/SNAP */
	int s, error = 0, sz;
	struct atm_pseudohdr atmdst, *ad;
	register struct mbuf *m = m0;
	register struct rtentry *rt;
	struct atmllc *atmllc;
	u_int32_t atm_flags;

	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
		senderr(ENETDOWN);
	ifp->if_lastchange = time;

	/*
	 * check route
	 */
	if ((rt = rt0) != NULL) {

		if ((rt->rt_flags & RTF_UP) == 0) { /* route went down! */
			if ((rt0 = rt = RTALLOC1(dst, 0)) != NULL)
				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, 0);
				if ((rt = rt->rt_gwroute) == 0)
					senderr(EHOSTUNREACH);
			}
		}

		/* XXX: put RTF_REJECT code here if doing ATMARP */

	}

	/*
	 * check for non-native ATM traffic   (dst != NULL)
	 */
	if (dst) {
		switch (dst->sa_family) {
#ifdef INET
		case AF_INET:
			if (!atmresolve(rt, m, dst, &atmdst)) {
				m = NULL; 
				/* XXX: atmresolve already free'd it */
				senderr(EHOSTUNREACH);
				/* XXX: put ATMARP stuff here */
				/* XXX: watch who frees m on failure */
			}
			etype = ETHERTYPE_IP;
			break;
#endif
#ifdef INET6
		case AF_INET6:
			/*
			 * The bottom line here is to either queue the
			 * outgoing packet in the discovery engine, or fill
			 * in edst with something that'll work.
			 */
			if (m->m_flags & M_MCAST) {
				/*
				 * If multicast dest., then use IPv6 -> Ethernet
				 * mcast mapping.  Really simple.
				 */
				ETHER_MAP_IN6_MULTICAST(
				    ((struct sockaddr_in6 *)dst)->sin6_addr,
				    edst);
			} else {
				/* Do unicast neighbor discovery stuff. */
				if (!ipv6_discov_resolve(ifp, rt, m, dst, edst))
	 				return 0;
			}
			type = htons(ETHERTYPE_IPV6);
			break;
#endif /* INET6 */

		default:
#if defined(__NetBSD__) || defined(__OpenBSD__)
			printf("%s: can't handle af%d\n", ifp->if_xname, 
				dst->sa_family);
#elif defined(__FreeBSD__) || defined(__bsdi__)
			printf("%s%d: can't handle af%d\n", ifp->if_name, 
				ifp->if_unit, dst->sa_family);
#endif
			senderr(EAFNOSUPPORT);
		}

		/*
		 * must add atm_pseudohdr to data
		 */
		sz = sizeof(atmdst);
		atm_flags = ATM_PH_FLAGS(&atmdst);
		if (atm_flags & ATM_PH_LLCSNAP) sz += 8; /* sizeof snap == 8 */
		M_PREPEND(m, sz, M_DONTWAIT);
		if (m == 0)
			senderr(ENOBUFS);
		ad = mtod(m, struct atm_pseudohdr *);
		*ad = atmdst;
		if (atm_flags & ATM_PH_LLCSNAP) {
			atmllc = (struct atmllc *)(ad + 1);
			bcopy(ATMLLC_HDR, atmllc->llchdr, 
						sizeof(atmllc->llchdr));
			ATM_LLC_SETTYPE(atmllc, etype); 
					/* note: already in network order */
		}
	}

	/*
	 * Queue message on interface, and start output if interface
	 * not yet active.
	 */

	s = splimp();
	if (IF_QFULL(&ifp->if_snd)) {
		IF_DROP(&ifp->if_snd);
		splx(s);
		senderr(ENOBUFS);
	}
	ifp->if_obytes += m->m_pkthdr.len;
	IF_ENQUEUE(&ifp->if_snd, m);
	if ((ifp->if_flags & IFF_OACTIVE) == 0)
		(*ifp->if_start)(ifp);
	splx(s);
	return (error);

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

/*
 * Process a received ATM packet;
 * the packet is in the mbuf chain m.
 */
void
atm_input(ifp, ah, m, rxhand)
	struct ifnet *ifp;
	register struct atm_pseudohdr *ah;
	struct mbuf *m;
	void *rxhand;
{
	register struct ifqueue *inq;
	u_int16_t etype = ETHERTYPE_IP; /* default */
	int s;

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

	if (rxhand) {
#ifdef NATM
	  struct natmpcb *npcb = rxhand;
	  s = splimp();			/* in case 2 atm cards @ diff lvls */
	  npcb->npcb_inq++;			/* count # in queue */
	  splx(s);
	  schednetisr(NETISR_NATM);
	  inq = &natmintrq;
	  m->m_pkthdr.rcvif = rxhand; /* XXX: overload */
#else
	  printf("atm_input: NATM detected but not configured in kernel\n");
	  m_freem(m);
	  return;
#endif
	} else {
	  /*
	   * handle LLC/SNAP header, if present
	   */
	  if (ATM_PH_FLAGS(ah) & ATM_PH_LLCSNAP) {
	    struct atmllc *alc;
	    if (m->m_len < sizeof(*alc) && (m = m_pullup(m, sizeof(*alc))) == 0)
		  return; /* failed */
	    alc = mtod(m, struct atmllc *);
	    if (bcmp(alc, ATMLLC_HDR, 6)) {
#if defined(__NetBSD__) || defined(__OpenBSD__)
	      printf("%s: recv'd invalid LLC/SNAP frame [vp=%d,vc=%d]\n",
		  ifp->if_xname, ATM_PH_VPI(ah), ATM_PH_VCI(ah));
#elif defined(__FreeBSD__) || defined(__bsdi__)
	      printf("%s%d: recv'd invalid LLC/SNAP frame [vp=%d,vc=%d]\n",
		  ifp->if_name, ifp->if_unit, ATM_PH_VPI(ah), ATM_PH_VCI(ah));
#endif
	      m_freem(m);
              return;
	    }
	    etype = ATM_LLC_TYPE(alc);
	    m_adj(m, sizeof(*alc));
	  }

	  switch (etype) {
#ifdef INET
	  case ETHERTYPE_IP:
		  schednetisr(NETISR_IP);
		  inq = &ipintrq;
		  break;
#endif
#ifdef INET6
	case ETHERTYPE_IPV6:
		schednetisr(NETISR_IPV6);
		inq = &ipv6intrq;
		break;
#endif /* INET6 */
	  default:
	      m_freem(m);
	      return;
	  }
	}

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

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

	ifp->if_type = IFT_ATM;
	ifp->if_addrlen = 0;
	ifp->if_hdrlen = 0;
	ifp->if_mtu = ATMMTU;
	ifp->if_output = atm_output;

#if defined(__NetBSD__) || defined(__OpenBSD__)
	for (ifa = ifp->if_addrlist.tqh_first; ifa != 0;
	    ifa = ifa->ifa_list.tqe_next)
#elif defined(__FreeBSD__) || defined(__bsdi__)
	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next) 
#endif

		if ((sdl = (struct sockaddr_dl *)ifa->ifa_addr) &&
		    sdl->sdl_family == AF_LINK) {
			sdl->sdl_type = IFT_ATM;
			sdl->sdl_alen = ifp->if_addrlen;
#ifdef notyet /* if using ATMARP, store hardware address using the next line */
			bcopy(ifp->hw_addr, LLADDR(sdl), ifp->if_addrlen);
#endif
			break;
		}
}