iso_snpac.c

早期freebsd实现

 *
 * RETURNS:			
 *
 * SIDE EFFECTS:	
 *
 * NOTES:			If entry already exists, then update holding time.
 */
snpac_add(ifp, nsap, snpa, type, ht, nsellength)
struct ifnet		*ifp;		/* interface info is related to */
struct iso_addr		*nsap;		/* nsap to add */
caddr_t				snpa;		/* translation */
char				type;		/* SNPA_IS or SNPA_ES */
u_short				ht;			/* holding time (in seconds) */
int					nsellength;	/* nsaps may differ only in trailing bytes */
{
	register struct	llinfo_llc *lc;
	register struct rtentry *rt;
	struct	rtentry *mrt = 0;
	register struct	iso_addr *r; /* for zap_isoaddr macro */
	int		snpalen = min(ifp->if_addrlen, MAX_SNPALEN);
	int		new_entry = 0, index = ifp->if_index, iftype = ifp->if_type;

	IFDEBUG(D_SNPA)
		printf("snpac_add(%x, %x, %x, %x, %x, %x)\n",
			ifp, nsap, snpa, type, ht, nsellength);
	ENDDEBUG
	zap_isoaddr(dst, nsap);
	rt = rtalloc1(S(dst), 0);
	IFDEBUG(D_SNPA)
		printf("snpac_add: rtalloc1 returns %x\n", rt);
	ENDDEBUG
	if (rt == 0) {
		struct sockaddr *netmask;
		int flags;
		add:
		if (nsellength) {
			netmask = S(msk); flags = RTF_UP;
			snpac_fixdstandmask(nsellength);
		} else {
			netmask = 0; flags = RTF_UP | RTF_HOST;
		}
		new_entry = 1;
		zap_linkaddr((&gte_dl), snpa, snpalen, index);
		gte_dl.sdl_type = iftype;
		if (rtrequest(RTM_ADD, S(dst), S(gte_dl), netmask, flags, &mrt) ||
			mrt == 0)
			return (0);
		rt = mrt;
		rt->rt_refcnt--;
	} else {
		register struct sockaddr_dl *sdl = (struct sockaddr_dl *)rt->rt_gateway;
		rt->rt_refcnt--;
		if ((rt->rt_flags & RTF_LLINFO) == 0)
			goto add;
		if (nsellength && (rt->rt_flags & RTF_HOST)) {
			if (rt->rt_refcnt == 0) {
				rtrequest(RTM_DELETE, S(dst), (struct sockaddr *)0,
					(struct sockaddr *)0, 0, (struct rtentry *)0);
				rt = 0;
				goto add;
			} else {
				static struct iso_addr nsap2; register char *cp;
				nsap2 = *nsap;
				cp = nsap2.isoa_genaddr + nsap->isoa_len - nsellength;
				while (cp < (char *)(1 + &nsap2))
					*cp++ = 0;
				(void) snpac_add(ifp, &nsap2, snpa, type, ht, nsellength);
			}
		}
		if (sdl->sdl_family != AF_LINK || sdl->sdl_alen == 0) {
			int old_sdl_len = sdl->sdl_len;
			if (old_sdl_len < sizeof(*sdl)) {
				log(LOG_DEBUG, "snpac_add: cant make room for lladdr\n");
				return (0);
			}
			zap_linkaddr(sdl, snpa, snpalen, index);
			sdl->sdl_len = old_sdl_len;
			sdl->sdl_type = iftype;
			new_entry = 1;
		}
	}
	if ((lc = (struct llinfo_llc *)rt->rt_llinfo) == 0)
		panic("snpac_rtrequest");
	rt->rt_rmx.rmx_expire = ht + time.tv_sec;
	lc->lc_flags = SNPA_VALID | type;
	if ((type & SNPA_IS) && !(iso_systype & SNPA_IS))
		snpac_logdefis(rt);
	return (new_entry);
}

static void
snpac_fixdstandmask(nsellength)
{
	register char *cp = msk.siso_data, *cplim;

	cplim = cp + (dst.siso_nlen -= nsellength);
	msk.siso_len = cplim - (char *)&msk;
	msk.siso_nlen = 0;
	while (cp < cplim)
		*cp++ = -1;
	while (cp < (char *)msk.siso_pad)
		*cp++ = 0;
	for (cp = dst.siso_data + dst.siso_nlen; cp < (char *)dst.siso_pad; )
		*cp++ = 0;
}

/*
 * FUNCTION:		snpac_ioctl
 *
 * PURPOSE:			Set/Get the system type and esis parameters
 *
 * RETURNS:			0 on success, or unix error code
 *
 * SIDE EFFECTS:	
 *
 * NOTES:			
 */
snpac_ioctl (so, cmd, data)
struct socket *so;
int		cmd;	/* ioctl to process */
caddr_t	data;	/* data for the cmd */
{
	register struct systype_req *rq = (struct systype_req *)data;

	IFDEBUG(D_IOCTL)
		if (cmd == SIOCSSTYPE)
			printf("snpac_ioctl: cmd set, type x%x, ht %d, ct %d\n",
				rq->sr_type, rq->sr_holdt, rq->sr_configt);
		else
			printf("snpac_ioctl: cmd get\n");
	ENDDEBUG

	if (cmd == SIOCSSTYPE) {
		if ((so->so_state & SS_PRIV) == 0)
			return (EPERM);
		if ((rq->sr_type & (SNPA_ES|SNPA_IS)) == (SNPA_ES|SNPA_IS))
			return(EINVAL);
		if (rq->sr_type & SNPA_ES) {
			iso_systype = SNPA_ES;
		} else if (rq->sr_type & SNPA_IS) {
			iso_systype = SNPA_IS;
		} else {
			return(EINVAL);
		}
		esis_holding_time = rq->sr_holdt;
		esis_config_time = rq->sr_configt;
		if (esis_esconfig_time != rq->sr_esconfigt) {
			untimeout(esis_config, (caddr_t)0);
			esis_esconfig_time = rq->sr_esconfigt;
			esis_config();
		}
	} else if (cmd == SIOCGSTYPE) {
		rq->sr_type = iso_systype;
		rq->sr_holdt = esis_holding_time;
		rq->sr_configt = esis_config_time;
		rq->sr_esconfigt = esis_esconfig_time;
	} else {
		return (EINVAL);
	}
	return (0);
}

/*
 * FUNCTION:		snpac_logdefis
 *
 * PURPOSE:			Mark the IS passed as the default IS
 *
 * RETURNS:			nothing
 *
 * SIDE EFFECTS:	
 *
 * NOTES:			
 */
snpac_logdefis(sc)
register struct rtentry *sc;
{
	register struct iso_addr *r;
	register struct sockaddr_dl *sdl = (struct sockaddr_dl *)sc->rt_gateway;
	register struct rtentry *rt;

	if (known_is == sc || !(sc->rt_flags & RTF_HOST))
		return;
	if (known_is) {
		RTFREE(known_is);
	}
	known_is = sc;
	sc->rt_refcnt++;
	rt = rtalloc1((struct sockaddr *)&zsi, 0);
	if (rt == 0)
		rtrequest(RTM_ADD, S(zsi), rt_key(sc), S(zmk),
						RTF_DYNAMIC|RTF_GATEWAY, 0);
	else {
		if ((rt->rt_flags & RTF_DYNAMIC) && 
		    (rt->rt_flags & RTF_GATEWAY) && rt_mask(rt)->sa_len == 0)
			rt_setgate(rt, rt_key(rt), rt_key(sc));
	}
}

/*
 * FUNCTION:		snpac_age
 *
 * PURPOSE:			Time out snpac entries
 *
 * RETURNS:			
 *
 * SIDE EFFECTS:	
 *
 * NOTES:			When encountering an entry for the first time, snpac_age
 *					may delete up to SNPAC_AGE too many seconds. Ie.
 *					if the entry is added a moment before snpac_age is
 *					called, the entry will immediately have SNPAC_AGE
 *					seconds taken off the holding time, even though
 *					it has only been held a brief moment.
 *
 *					The proper way to do this is set an expiry timeval
 *					equal to current time + holding time. Then snpac_age
 *					would time out entries where expiry date is older
 *					than the current time.
 */
void
snpac_age()
{
	register struct	llinfo_llc *lc, *nlc;
	register struct	rtentry *rt;

	timeout(snpac_age, (caddr_t)0, SNPAC_AGE * hz);

	for (lc = llinfo_llc.lc_next; lc != & llinfo_llc; lc = nlc) {
		nlc = lc->lc_next;
		if (lc->lc_flags & SNPA_VALID) {
			rt = lc->lc_rt;
			if (rt->rt_rmx.rmx_expire && rt->rt_rmx.rmx_expire < time.tv_sec)
				snpac_free(lc);
		}
	}
}

/*
 * FUNCTION:		snpac_ownmulti
 *
 * PURPOSE:			Determine if the snpa address is a multicast address
 *					of the same type as the system.
 *
 * RETURNS:			true or false
 *
 * SIDE EFFECTS:	
 *
 * NOTES:			Used by interface drivers when not in eavesdrop mode 
 *					as interm kludge until
 *					real multicast addresses can be configured
 */
snpac_ownmulti(snpa, len)
caddr_t	snpa;
u_int	len;
{
	return (((iso_systype & SNPA_ES) &&
			 (!bcmp(snpa, (caddr_t)all_es_snpa, len))) ||
			((iso_systype & SNPA_IS) &&
			 (!bcmp(snpa, (caddr_t)all_is_snpa, len))));
}

/*
 * FUNCTION:		snpac_flushifp
 *
 * PURPOSE:			Flush entries associated with specific ifp
 *
 * RETURNS:			nothing
 *
 * SIDE EFFECTS:	
 *
 * NOTES:			
 */
snpac_flushifp(ifp)
struct ifnet	*ifp;
{
	register struct llinfo_llc	*lc;

	for (lc = llinfo_llc.lc_next; lc != & llinfo_llc; lc = lc->lc_next) {
		if (lc->lc_rt->rt_ifp == ifp && (lc->lc_flags & SNPA_VALID))
			snpac_free(lc);
	}
}

/*
 * FUNCTION:		snpac_rtrequest
 *
 * PURPOSE:			Make a routing request
 *
 * RETURNS:			nothing
 *
 * SIDE EFFECTS:	
 *
 * NOTES:			In the future, this should make a request of a user
 *					level routing daemon.
 */
snpac_rtrequest(req, host, gateway, netmask, flags, ret_nrt)
int				req;
struct iso_addr	*host;
struct iso_addr	*gateway;
struct iso_addr	*netmask;
short			flags;
struct rtentry	**ret_nrt;
{
	register struct iso_addr *r;

	IFDEBUG(D_SNPA)
		printf("snpac_rtrequest: ");
		if (req == RTM_ADD)
			printf("add");
		else if (req == RTM_DELETE)
			printf("delete");
		else 
			printf("unknown command");
		printf(" dst: %s\n", clnp_iso_addrp(host));
		printf("\tgateway: %s\n", clnp_iso_addrp(gateway));
	ENDDEBUG


	zap_isoaddr(dst, host);
	zap_isoaddr(gte, gateway);
	if (netmask) {
		zap_isoaddr(msk, netmask);
		msk.siso_nlen = 0;
		msk.siso_len = msk.siso_pad - (u_char *)&msk;
	}

	rtrequest(req, S(dst), S(gte), (netmask ? S(msk) : (struct sockaddr *)0),
		flags, ret_nrt);
}

/*
 * FUNCTION:		snpac_addrt
 *
 * PURPOSE:			Associate a routing entry with an snpac entry
 *
 * RETURNS:			nothing
 *
 * SIDE EFFECTS:	
 *
 * NOTES:			If a cache entry exists for gateway, then
 *					make a routing entry (host, gateway) and associate
 *					with gateway.
 *
 *					If a route already exists and is different, first delete
 *					it.
 *
 *					This could be made more efficient by checking 
 *					the existing route before adding a new one.
 */
snpac_addrt(ifp, host, gateway, netmask)
struct ifnet *ifp;
struct iso_addr	*host, *gateway, *netmask;
{
	register struct iso_addr *r;

	zap_isoaddr(dst, host);
	zap_isoaddr(gte, gateway);
	if (netmask) {
		zap_isoaddr(msk, netmask);
		msk.siso_nlen = 0;
		msk.siso_len = msk.siso_pad - (u_char *)&msk;
		rtredirect(S(dst), S(gte), S(msk), RTF_DONE, S(gte), 0);
	} else
		rtredirect(S(dst), S(gte), (struct sockaddr *)0,
							RTF_DONE | RTF_HOST, S(gte), 0);
}
#endif	/* ISO */