iso_snpac.c

早期freebsd实现

/*-
 * Copyright (c) 1991, 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.
 *
 *	@(#)iso_snpac.c	8.1 (Berkeley) 6/10/93
 */

/***********************************************************
		Copyright IBM Corporation 1987

                      All Rights Reserved

Permission to use, copy, modify, and distribute this software and its 
documentation for any purpose and without fee is hereby granted, 
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in 
supporting documentation, and that the name of IBM not be
used in advertising or publicity pertaining to distribution of the
software without specific, written prior permission.  

IBM DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
IBM BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
SOFTWARE.

******************************************************************/

/*
 * ARGO Project, Computer Sciences Dept., University of Wisconsin - Madison
 */
/* $Header: iso_snpac.c,v 1.8 88/09/19 13:51:36 hagens Exp $ */
/* $Source: /usr/argo/sys/netiso/RCS/iso_snpac.c,v $ */

#ifdef ISO

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/syslog.h>

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

#include <netiso/iso.h>
#include <netiso/iso_var.h>
#include <netiso/iso_snpac.h>
#include <netiso/clnp.h>
#include <netiso/clnp_stat.h>
#include <netiso/esis.h>
#include <netiso/argo_debug.h>

int 				iso_systype = SNPA_ES;	/* default to be an ES */
extern short	esis_holding_time, esis_config_time, esis_esconfig_time;
extern struct	timeval time;
extern void esis_config();
extern int hz;
static void snpac_fixdstandmask();

struct sockaddr_iso blank_siso = {sizeof(blank_siso), AF_ISO};
extern u_long iso_hashchar();
static struct sockaddr_iso
	dst	= {sizeof(dst), AF_ISO},
	gte	= {sizeof(dst), AF_ISO},
	src	= {sizeof(dst), AF_ISO},
	msk	= {sizeof(dst), AF_ISO},
	zmk = {0};
#define zsi blank_siso
#define zero_isoa	zsi.siso_addr
#define zap_isoaddr(a, b) {Bzero(&a.siso_addr, sizeof(*r)); r = b; \
	   Bcopy(r, &a.siso_addr, 1 + (r)->isoa_len);}
#define S(x) ((struct sockaddr *)&(x))

static struct sockaddr_dl blank_dl = {sizeof(blank_dl), AF_LINK};
static struct sockaddr_dl gte_dl;
#define zap_linkaddr(a, b, c, i) \
	(*a = blank_dl, bcopy(b, a->sdl_data, a->sdl_alen = c), a->sdl_index = i)

/*
 *	We only keep track of a single IS at a time.
 */
struct rtentry	*known_is;

/*
 *	Addresses taken from NBS agreements, December 1987.
 *
 *	These addresses assume on-the-wire transmission of least significant
 *	bit first. This is the method used by 802.3. When these
 *	addresses are passed to the token ring driver, (802.5), they
 *	must be bit-swaped because 802.5 transmission order is MSb first.
 *
 *	Furthermore, according to IBM Austin, these addresses are not
 *	true token ring multicast addresses. More work is necessary
 *	to get multicast to work right on token ring.
 *
 *	Currently, the token ring driver does not handle multicast, so
 *	these addresses are converted into the broadcast address in
 *	lan_output() That means that if these multicast addresses change
 *	the token ring driver must be altered.
 */
char all_es_snpa[] = { 0x09, 0x00, 0x2b, 0x00, 0x00, 0x04 };
char all_is_snpa[] = { 0x09, 0x00, 0x2b, 0x00, 0x00, 0x05 };
char all_l1is_snpa[] = {0x01, 0x80, 0xc2, 0x00, 0x00, 0x14};
char all_l2is_snpa[] = {0x01, 0x80, 0xc2, 0x00, 0x00, 0x15};

union sockunion {
	struct sockaddr_iso siso;
	struct sockaddr_dl	sdl;
	struct sockaddr		sa;
};

/*
 * FUNCTION:		llc_rtrequest
 *
 * PURPOSE:			Manage routing table entries specific to LLC for ISO.
 *
 * NOTES:			This does a lot of obscure magic;
 */
llc_rtrequest(req, rt, sa)
int req;
register struct rtentry *rt;
struct sockaddr *sa;
{
	register union sockunion *gate = (union sockunion *)rt->rt_gateway;
	register struct llinfo_llc *lc = (struct llinfo_llc *)rt->rt_llinfo, *lc2;
	struct rtentry *rt2;
	struct ifnet *ifp = rt->rt_ifp;
	int addrlen = ifp->if_addrlen;
#define LLC_SIZE 3 /* XXXXXX do this right later */

	IFDEBUG (D_SNPA)
		printf("llc_rtrequest(%d, %x, %x)\n", req, rt, sa);
	ENDDEBUG
	if (rt->rt_flags & RTF_GATEWAY)
		return;
	else switch (req) {
	case RTM_ADD:
		/*
		 * Case 1: This route may come from a route to iface with mask
		 * or from a default route.
		 */
		if (rt->rt_flags & RTF_CLONING) {
			iso_setmcasts(ifp, req);
			rt_setgate(rt, rt_key(rt), &blank_dl);
			return;
		}
		if (lc != 0)
			return; /* happens on a route change */
		/* FALLTHROUGH */
	case RTM_RESOLVE:
		/*
		 * Case 2:  This route may come from cloning, or a manual route
		 * add with a LL address.
		 */
		if (gate->sdl.sdl_family != AF_LINK) {
			log(LOG_DEBUG, "llc_rtrequest: got non-link non-gateway route\n");
			break;
		}
		R_Malloc(lc, struct llinfo_llc *, sizeof (*lc));
		rt->rt_llinfo = (caddr_t)lc;
		if (lc == 0) {
			log(LOG_DEBUG, "llc_rtrequest: malloc failed\n");
			break;
		}
		Bzero(lc, sizeof(*lc));
		lc->lc_rt = rt;
		rt->rt_flags |= RTF_LLINFO;
		insque(lc, &llinfo_llc);
		if (gate->sdl.sdl_alen == sizeof(struct esis_req) + addrlen) {
			gate->sdl.sdl_alen -= sizeof(struct esis_req);
			bcopy(addrlen + LLADDR(&gate->sdl),
				  (caddr_t)&lc->lc_er, sizeof(lc->lc_er));
		} else if (gate->sdl.sdl_alen == addrlen)
			lc->lc_flags = (SNPA_ES | SNPA_VALID | SNPA_PERM);
		break;
	case RTM_DELETE:
		if (rt->rt_flags & RTF_CLONING)
			iso_setmcasts(ifp, req);
		if (lc == 0)
			return;
		remque(lc);
		Free(lc);
		rt->rt_llinfo = 0;
		rt->rt_flags &= ~RTF_LLINFO;
		break;
	}
	if (rt->rt_rmx.rmx_mtu == 0) {
			rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu - LLC_SIZE;
	}
}
/*
 * FUNCTION:		iso_setmcasts
 *
 * PURPOSE:			Enable/Disable ESIS/ISIS multicast reception on interfaces.
 *
 * NOTES:			This also does a lot of obscure magic;
 */
iso_setmcasts(ifp, req)
	struct	ifnet *ifp;
	int		req;
{
	static char *addrlist[] =
		{ all_es_snpa, all_is_snpa, all_l1is_snpa, all_l2is_snpa, 0};
	struct ifreq ifr;
	register caddr_t *cpp;
	int		doreset = 0;

	bzero((caddr_t)&ifr, sizeof(ifr));
	for (cpp = (caddr_t *)addrlist; *cpp; cpp++) {
		bcopy(*cpp, (caddr_t)ifr.ifr_addr.sa_data, 6);
		if (req == RTM_ADD)
			if (ether_addmulti(&ifr, (struct arpcom *)ifp) == ENETRESET)
				doreset++;
		else
			if (ether_delmulti(&ifr, (struct arpcom *)ifp) == ENETRESET)
				doreset++;
	}
	if (doreset) {
		if (ifp->if_reset)
			(*ifp->if_reset)(ifp->if_unit);
		else
			printf("iso_setmcasts: %s%d needs reseting to receive iso mcasts\n",
					ifp->if_name, ifp->if_unit);
	}
}
/*
 * FUNCTION:		iso_snparesolve
 *
 * PURPOSE:			Resolve an iso address into snpa address
 *
 * RETURNS:			0 if addr is resolved
 *					errno if addr is unknown
 *
 * SIDE EFFECTS:	
 *
 * NOTES:			Now that we have folded the snpa cache into the routing
 *					table, we know there is no snpa address known for this
 *					destination.  If we know of a default IS, then the address
 *					of the IS is returned.  If no IS is known, then return the
 *					multi-cast address for "all ES" for this interface.
 *
 *					NB: the last case described above constitutes the
 *					query configuration function 9542, sec 6.5
 *					A mechanism is needed to prevent this function from
 *					being invoked if the system is an IS.
 */
iso_snparesolve(ifp, dest, snpa, snpa_len)
struct	ifnet *ifp;			/* outgoing interface */
struct	sockaddr_iso *dest;	/* destination */
caddr_t	snpa;				/* RESULT: snpa to be used */
int		*snpa_len;			/* RESULT: length of snpa */
{
	struct	llinfo_llc *sc;	/* ptr to snpa table entry */
	caddr_t	found_snpa;
	int 	addrlen;

	/*
	 *	This hack allows us to send esis packets that have the destination snpa
	 *	addresss embedded in the destination nsap address 
	 */
	if (dest->siso_data[0] == AFI_SNA) {
		/*
		 *	This is a subnetwork address. Return it immediately
		 */
		IFDEBUG(D_SNPA)
			printf("iso_snparesolve: return SN address\n");
		ENDDEBUG
		addrlen = dest->siso_nlen - 1;	/* subtract size of AFI */
		found_snpa = (caddr_t) dest->siso_data + 1;
	/* 
	 * If we are an IS, we can't do much with the packet;
	 *	Check if we know about an IS.
	 */
	} else if (iso_systype != SNPA_IS && known_is != 0 &&
				(sc = (struct llinfo_llc *)known_is->rt_llinfo) &&
				 (sc->lc_flags & SNPA_VALID)) {
		register struct sockaddr_dl *sdl =
			(struct sockaddr_dl *)(known_is->rt_gateway);
		found_snpa = LLADDR(sdl);
		addrlen = sdl->sdl_alen;
	} else if (ifp->if_flags & IFF_BROADCAST) {
		/* 
		 *	no IS, no match. Return "all es" multicast address for this
		 *	interface, as per Query Configuration Function (9542 sec 6.5)
		 *
		 *	Note: there is a potential problem here. If the destination
		 *	is on the subnet and it does not respond with a ESH, but
		 *	does send back a TP CC, a connection could be established
		 *	where we always transmit the CLNP packet to "all es"
		 */
		addrlen = ifp->if_addrlen;
		found_snpa = (caddr_t)all_es_snpa;
	} else
		return (ENETUNREACH);
	bcopy(found_snpa, snpa, *snpa_len = addrlen);
	return (0);
}


/*
 * FUNCTION:		snpac_free
 *
 * PURPOSE:			free an entry in the iso address map table
 *
 * RETURNS:			nothing
 *
 * SIDE EFFECTS:	
 *
 * NOTES:			If there is a route entry associated with cache
 *					entry, then delete that as well
 */
snpac_free(lc)
register struct llinfo_llc *lc;		/* entry to free */
{
	register struct rtentry *rt = lc->lc_rt;
	register struct iso_addr *r;

	if (known_is == rt)
		known_is = 0;
	if (rt && (rt->rt_flags & RTF_UP) &&
		(rt->rt_flags & (RTF_DYNAMIC | RTF_MODIFIED))) {
			RTFREE(rt);
			rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway, rt_mask(rt),
						rt->rt_flags, (struct rtentry **)0);
		RTFREE(rt);
	}
}

/*
 * FUNCTION:		snpac_add
 *
 * PURPOSE:			Add an entry to the snpa cache