/*
 * Copyright (c) 1998, Larry Lile
 * All rights reserved.
 *
 * For latest sources and information on this driver, please
 * go to http://anarchy.stdio.com.
 *
 * Questions, comments or suggestions should be directed to
 * Larry Lile <lile@stdio.com>.
 *
 * 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 unmodified, 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 *
 * $FreeBSD: src/sys/net/if_iso88025subr.c,v 1.7.2.7 2002/06/18 00:15:31 kbyanc Exp $
 * $DragonFly: src/sys/net/Attic/if_iso88025subr.c,v 1.11 2005/01/06 09:14:13 hsu Exp $
 *
 */

/*
 *
 * General ISO 802.5 (Token Ring) support routines
 *
 */

#include "opt_inet.h"

#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/sockio.h>
#include <sys/sysctl.h>

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

#include <net/if_arp.h>

#include <net/iso88025.h>

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

#include <net/bpf.h>

#include <machine/clock.h>
#include <machine/md_var.h>

#include <bus/isa/i386/isa_device.h>

#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>

#include <sys/kernel.h>
#include <net/iso88025.h>

static int	iso88025_output(struct ifnet *, struct mbuf *,
				struct sockaddr *, struct rtentry *);
static void	iso88025_input(struct ifnet *, struct mbuf *);

void
iso88025_ifattach(struct ifnet *ifp)
{
	struct ifaddr *ifa = NULL;
	struct sockaddr_dl *sdl;

	ifp->if_input = iso88025_input;
	ifp->if_output = iso88025_output;
	if_attach(ifp);
	ifp->if_type = IFT_ISO88025;
	ifp->if_addrlen = ISO88025_ADDR_LEN;
	ifp->if_hdrlen = ISO88025_HDR_LEN;
	if (ifp->if_baudrate == 0)
		ifp->if_baudrate = TR_16MBPS; /* 16Mbit should be a safe default */
	if (ifp->if_mtu == 0)
		ifp->if_mtu = ISO88025_DEFAULT_MTU;

	ifa = ifnet_addrs[ifp->if_index - 1];
	if (ifa == NULL) {
		printf("iso88025_ifattach: no lladdr!\n");
		return;
	}
	sdl = (struct sockaddr_dl *)ifa->ifa_addr;
	sdl->sdl_type = IFT_ISO88025;
	sdl->sdl_alen = ifp->if_addrlen;
	bcopy(((struct arpcom *)ifp)->ac_enaddr, LLADDR(sdl), ifp->if_addrlen);
	bpfattach(ifp, DLT_IEEE802, sizeof(struct iso88025_header));
}

int
iso88025_ioctl(struct ifnet *ifp, int command, caddr_t data)
{
	struct ifaddr *ifa = (struct ifaddr *) data;
	struct ifreq *ifr = (struct ifreq *) data;
	int error = 0;

	switch (command) {
	case SIOCSIFADDR:
		ifp->if_flags |= IFF_UP;

		switch (ifa->ifa_addr->sa_family) {
#ifdef INET
		case AF_INET:
			ifp->if_init(ifp->if_softc);	/* before arpwhohas */
			arp_ifinit(ifp, ifa);
			break;
#endif
		default:
			ifp->if_init(ifp->if_softc);
			break;
		}
		break;

	case SIOCGIFADDR:
		bcopy(((struct arpcom *)ifp->if_softc)->ac_enaddr,
		      ((struct sockaddr *)ifr->ifr_data)->sa_data,
		      ISO88025_ADDR_LEN);
		break;

	case SIOCSIFMTU:
		/*
		 * Set the interface MTU.
		 */
		if (ifr->ifr_mtu > ISO88025_MAX_MTU) {
			error = EINVAL;
		} else {
			ifp->if_mtu = ifr->ifr_mtu;
		}
		break;
	}
	return (error);
}

/*
 * ISO88025 encapsulation
 */
static int
iso88025_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
		struct rtentry *rt0)
{
	struct iso88025_header *th;
	struct iso88025_header gen_th;
	struct iso88025_sockaddr_data *sd = (struct iso88025_sockaddr_data *)dst->sa_data;
	struct llc *l;
	struct sockaddr_dl *sdl = NULL;
	int s, error = 0, rif_len = 0;
	u_char edst[6];
	struct rtentry *rt;
	int len = m->m_pkthdr.len, loop_copy = 0;
	struct arpcom *ac = (struct arpcom *)ifp;

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

	if (rt0 == NULL)
		senderr(EHOSTUNREACH);
	error = rt_llroute(dst, rt0, &rt);
	if (error != 0)
		senderr(error);

	/* Calculate routing info length based on arp table entry. */
	if (rt && (sdl = (struct sockaddr_dl *)rt->rt_gateway))
		if (SDL_ISO88025(sdl)->trld_rcf != NULL)
			rif_len = TR_RCF_RIFLEN(SDL_ISO88025(sdl)->trld_rcf);

	/* Generate a generic 802.5 header for the packet. */
	gen_th.ac = TR_AC;
	gen_th.fc = TR_LLC_FRAME;
	memcpy(gen_th.iso88025_shost, ac->ac_enaddr, sizeof ac->ac_enaddr);
	if (rif_len) {
		gen_th.iso88025_shost[0] |= TR_RII;
		if (rif_len > 2) {
			gen_th.rcf = sdl->sdl_rcf;
			memcpy(gen_th.rd, sdl->sdl_route, rif_len - 2);
		}
	}


	switch (dst->sa_family) {
#ifdef INET
	case AF_INET:
		if (!arpresolve(ifp, rt0, m, dst, edst))
			return (0);	/* if not yet resolved */
		/* Add LLC and SNAP headers */
		M_PREPEND(m, 8, MB_DONTWAIT);
		if (m == NULL)
			return (ENOBUFS);
		l = mtod(m, struct llc *);
		l->llc_un.type_snap.ether_type = htons(ETHERTYPE_IP);
		l->llc_dsap = l->llc_ssap = LLC_SNAP_LSAP;
		l->llc_un.type_snap.control = LLC_UI;
		l->llc_un.type_snap.org_code[0] = 0x0;
		l->llc_un.type_snap.org_code[1] = 0x0;
		l->llc_un.type_snap.org_code[2] = 0x0;
		memcpy(gen_th.iso88025_dhost, edst, sizeof(edst));
		break;
#endif

	case AF_UNSPEC:
		/*
		 * For AF_UNSPEC sockaddr.sa_data must contain all of the
		 * mac information needed to send the packet.  This allows
		 * full mac, llc, and source routing function to be controlled.
		 * llc and source routing information must already be in the
		 * mbuf provided, ac/fc are set in sa_data.  sockaddr.sa_data
		 * should be a iso88025_sockaddr_data structure see iso88025.h
		 */
		loop_copy = -1;
		sd = (struct iso88025_sockaddr_data *)dst->sa_data;
		gen_th.ac = sd->ac;
		gen_th.fc = sd->fc;
		memcpy(gen_th.iso88025_dhost, sd->ether_dhost, sizeof(sd->ether_dhost));
		memcpy(gen_th.iso88025_shost, sd->ether_shost, sizeof(sd->ether_shost));
		rif_len = 0;
		break;

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

	/*
	 * Add local net header.  If no space in first mbuf,
	 * allocate another.
	 */

	M_PREPEND(m, ISO88025_HDR_LEN + rif_len, MB_DONTWAIT);
	if (m == NULL)
		return (ENOBUFS);

	/* Copy as much of the generic header as is needed into the mbuf */
	th = mtod(m, struct iso88025_header *);
	memcpy(th, &gen_th, ISO88025_HDR_LEN + rif_len);

	/*
	 * If a simplex interface, and the packet is being sent to our
	 * Ethernet address or a broadcast address, loopback a copy.
	 * XXX To make a simplex device behave exactly like a duplex
	 * device, we should copy in the case of sending to our own
	 * ethernet address (thus letting the original actually appear
	 * on the wire). However, we don't do that here for security
	 * reasons and compatibility with the original behavior.
	 */
	if ((ifp->if_flags & IFF_SIMPLEX) &&
	   (loop_copy != -1)) {
		if ((m->m_flags & M_BCAST) || (loop_copy > 0)) {
			struct mbuf *n = m_copypacket(m, MB_DONTWAIT);

			if_simloop(ifp, n, dst->sa_family, ISO88025_HDR_LEN);
		} else if (bcmp(th->iso88025_dhost,
		    th->iso88025_shost, ETHER_ADDR_LEN) == 0) {
			if_simloop(ifp, m, dst->sa_family, ISO88025_HDR_LEN);
			return (0);	/* XXX */
		}
	}

	s = splimp();
	/*
	 * Queue message on interface, and start output if interface
	 * not yet active.
	 */
	if (IF_QFULL(&ifp->if_snd)) {
		printf("iso88025_output: packet dropped QFULL.\n");
		IF_DROP(&ifp->if_snd);
		splx(s);
		senderr(ENOBUFS);
	}
	if (m->m_flags & M_MCAST)
		ifp->if_omcasts++;
	IF_ENQUEUE(&ifp->if_snd, m);
	if (!(ifp->if_flags & IFF_OACTIVE))
		(*ifp->if_start)(ifp);
	splx(s);
	ifp->if_obytes += len + ISO88025_HDR_LEN + 8;
	return (error);

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

/*
 * ISO 88025 de-encapsulation
 */
static void
iso88025_input(struct ifnet *ifp, struct mbuf *m)
{
	struct llc *l;
	struct iso88025_header *th = mtod(m, struct iso88025_header *);
	int isr, hdr_len;
	u_short ether_type;

	if (!(ifp->if_flags & IFF_UP)) {
		m_freem(m);
		return;
	}

	hdr_len = ISO88025_HDR_LEN;
	if (th->iso88025_shost[0] & 0x80)
		hdr_len += (ntohs(th->rcf) & 0x1f00) >> 8;

	if (m->m_len < hdr_len) {
		m_freem(m);
		return;
	}
	m->m_pkthdr.len -= hdr_len;
	m->m_len -= hdr_len;
	m->m_data += hdr_len;

	l = mtod(m, struct llc *);

	switch (l->llc_control) {
	case LLC_UI:
		break;
	case LLC_TEST:
	case LLC_TEST_P:
	{
		struct sockaddr sa;
		struct arpcom *ac = (struct arpcom *)ifp;
		struct iso88025_sockaddr_data *th2;
		int i;
		u_char c = l->llc_dsap;

		if (th->iso88025_shost[0] & TR_RII) { /* XXX */
			printf("iso88025_input: dropping source routed LLC_TEST\n");
			m_free(m);
			return;
		}
		l->llc_dsap = l->llc_ssap;
		l->llc_ssap = c;
		if (m->m_flags & (M_BCAST | M_MCAST))
			bcopy(ac->ac_enaddr, th->iso88025_dhost,
			      ISO88025_ADDR_LEN);
		sa.sa_family = AF_UNSPEC;
		sa.sa_len = sizeof(sa);
		th2 = (struct iso88025_sockaddr_data *)sa.sa_data;
		for (i = 0; i < ISO88025_ADDR_LEN; i++) {
			th2->ether_shost[i] = c = th->iso88025_dhost[i];
			th2->ether_dhost[i] = th->iso88025_dhost[i] = th->iso88025_shost[i];
			th->iso88025_shost[i] = c;
		}
		th2->ac = TR_AC;
		th2->fc = TR_LLC_FRAME;
		ifp->if_output(ifp, m, &sa, NULL);
		return;
	}
	default:
		printf("iso88025_input: unexpected llc control 0x%02x\n", l->llc_control);
		m_freem(m);
		return;
	}

	m->m_pkthdr.len -= 8;
	m->m_len -= 8;
	m->m_data += 8; /* Length of LLC header in our case */

	ifp->if_ibytes += m->m_pkthdr.len + sizeof(*th);
	if (th->iso88025_dhost[0] & 1) {
		if (bcmp(ifp->if_broadcastaddr, th->iso88025_dhost,
			 ifp->if_addrlen) == 0)
			m->m_flags |= M_BCAST;
		else
			m->m_flags |= M_MCAST;
	}
	if (m->m_flags & (M_BCAST|M_MCAST))
		ifp->if_imcasts++;

	ether_type = ntohs(l->llc_un.type_snap.ether_type);

	switch (ether_type) {
#ifdef INET
	case ETHERTYPE_IP:
		th->iso88025_shost[0] &= ~(TR_RII);
		if (ipflow_fastforward(m))
			return;
		isr = NETISR_IP;
		break;

	case ETHERTYPE_ARP:
		if (ifp->if_flags & IFF_NOARP) {
			m_freem(m);
			return;
		}
		isr = NETISR_ARP;
		break;
#endif
	default:
	    m_freem(m);
	    return;
	}

	netisr_dispatch(isr, m);
}