if_ethersubr.c

早期freebsd实现

		break;
#endif
#ifdef NS
	case ETHERTYPE_NS:
		schednetisr(NETISR_NS);
		inq = &nsintrq;
		break;

#endif
	default:
#if defined (ISO) || defined (LLC)
		if (eh->ether_type > ETHERMTU)
			goto dropanyway;
		l = mtod(m, struct llc *);
		switch (l->llc_dsap) {
#ifdef	ISO
		case LLC_ISO_LSAP: 
			switch (l->llc_control) {
			case LLC_UI:
				/* LLC_UI_P forbidden in class 1 service */
				if ((l->llc_dsap == LLC_ISO_LSAP) &&
				    (l->llc_ssap == LLC_ISO_LSAP)) {
					/* LSAP for ISO */
					if (m->m_pkthdr.len > eh->ether_type)
						m_adj(m, eh->ether_type - m->m_pkthdr.len);
					m->m_data += 3;		/* XXX */
					m->m_len -= 3;		/* XXX */
					m->m_pkthdr.len -= 3;	/* XXX */
					M_PREPEND(m, sizeof *eh, M_DONTWAIT);
					if (m == 0)
						return;
					*mtod(m, struct ether_header *) = *eh;
					IFDEBUG(D_ETHER)
						printf("clnp packet");
					ENDDEBUG
					schednetisr(NETISR_ISO);
					inq = &clnlintrq;
					break;
				}
				goto dropanyway;
				
			case LLC_XID:
			case LLC_XID_P:
				if(m->m_len < 6)
					goto dropanyway;
				l->llc_window = 0;
				l->llc_fid = 9;
				l->llc_class = 1;
				l->llc_dsap = l->llc_ssap = 0;
				/* Fall through to */
			case LLC_TEST:
			case LLC_TEST_P:
			{
				struct sockaddr sa;
				register struct ether_header *eh2;
				int i;
				u_char c = l->llc_dsap;

				l->llc_dsap = l->llc_ssap;
				l->llc_ssap = c;
				if (m->m_flags & (M_BCAST | M_MCAST))
					bcopy((caddr_t)ac->ac_enaddr,
					      (caddr_t)eh->ether_dhost, 6);
				sa.sa_family = AF_UNSPEC;
				sa.sa_len = sizeof(sa);
				eh2 = (struct ether_header *)sa.sa_data;
				for (i = 0; i < 6; i++) {
					eh2->ether_shost[i] = c = eh->ether_dhost[i];
					eh2->ether_dhost[i] = 
						eh->ether_dhost[i] = eh->ether_shost[i];
					eh->ether_shost[i] = c;
				}
				ifp->if_output(ifp, m, &sa, NULL);
				return;
			}
			default:
				m_freem(m);
				return;
			}
			break;
#endif /* ISO */
#ifdef LLC
		case LLC_X25_LSAP:
		{
			if (m->m_pkthdr.len > eh->ether_type)
				m_adj(m, eh->ether_type - m->m_pkthdr.len);
			M_PREPEND(m, sizeof(struct sdl_hdr) , M_DONTWAIT);
			if (m == 0)
				return;
			if ( !sdl_sethdrif(ifp, eh->ether_shost, LLC_X25_LSAP,
					    eh->ether_dhost, LLC_X25_LSAP, 6, 
					    mtod(m, struct sdl_hdr *)))
				panic("ETHER cons addr failure");
			mtod(m, struct sdl_hdr *)->sdlhdr_len = eh->ether_type;
#ifdef LLC_DEBUG
				printf("llc packet\n");
#endif /* LLC_DEBUG */
			schednetisr(NETISR_CCITT);
			inq = &llcintrq;
			break;
		}
#endif /* LLC */
		dropanyway:
		default:
			m_freem(m);
			return;
		}
#else /* ISO || LLC */
	    m_freem(m);
	    return;
#endif /* ISO || LLC */
	}

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

/*
 * Convert Ethernet address to printable (loggable) representation.
 */
static char digits[] = "0123456789abcdef";
char *
ether_sprintf(ap)
	register u_char *ap;
{
	register i;
	static char etherbuf[18];
	register char *cp = etherbuf;

	for (i = 0; i < 6; i++) {
		*cp++ = digits[*ap >> 4];
		*cp++ = digits[*ap++ & 0xf];
		*cp++ = ':';
	}
	*--cp = 0;
	return (etherbuf);
}

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

	ifp->if_type = IFT_ETHER;
	ifp->if_addrlen = 6;
	ifp->if_hdrlen = 14;
	ifp->if_mtu = ETHERMTU;
	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_ETHER;
			sdl->sdl_alen = ifp->if_addrlen;
			bcopy((caddr_t)((struct arpcom *)ifp)->ac_enaddr,
			      LLADDR(sdl), ifp->if_addrlen);
			break;
		}
}

u_char	ether_ipmulticast_min[6] = { 0x01, 0x00, 0x5e, 0x00, 0x00, 0x00 };
u_char	ether_ipmulticast_max[6] = { 0x01, 0x00, 0x5e, 0x7f, 0xff, 0xff };
/*
 * Add an Ethernet multicast address or range of addresses to the list for a
 * given interface.
 */
int
ether_addmulti(ifr, ac)
	struct ifreq *ifr;
	register struct arpcom *ac;
{
	register struct ether_multi *enm;
	struct sockaddr_in *sin;
	u_char addrlo[6];
	u_char addrhi[6];
	int s = splimp();

	switch (ifr->ifr_addr.sa_family) {

	case AF_UNSPEC:
		bcopy(ifr->ifr_addr.sa_data, addrlo, 6);
		bcopy(addrlo, addrhi, 6);
		break;

#ifdef INET
	case AF_INET:
		sin = (struct sockaddr_in *)&(ifr->ifr_addr);
		if (sin->sin_addr.s_addr == INADDR_ANY) {
			/*
			 * An IP address of INADDR_ANY means listen to all
			 * of the Ethernet multicast addresses used for IP.
			 * (This is for the sake of IP multicast routers.)
			 */
			bcopy(ether_ipmulticast_min, addrlo, 6);
			bcopy(ether_ipmulticast_max, addrhi, 6);
		}
		else {
			ETHER_MAP_IP_MULTICAST(&sin->sin_addr, addrlo);
			bcopy(addrlo, addrhi, 6);
		}
		break;
#endif

	default:
		splx(s);
		return (EAFNOSUPPORT);
	}

	/*
	 * Verify that we have valid Ethernet multicast addresses.
	 */
	if ((addrlo[0] & 0x01) != 1 || (addrhi[0] & 0x01) != 1) {
		splx(s);
		return (EINVAL);
	}
	/*
	 * See if the address range is already in the list.
	 */
	ETHER_LOOKUP_MULTI(addrlo, addrhi, ac, enm);
	if (enm != NULL) {
		/*
		 * Found it; just increment the reference count.
		 */
		++enm->enm_refcount;
		splx(s);
		return (0);
	}
	/*
	 * New address or range; malloc a new multicast record
	 * and link it into the interface's multicast list.
	 */
	enm = (struct ether_multi *)malloc(sizeof(*enm), M_IFMADDR, M_NOWAIT);
	if (enm == NULL) {
		splx(s);
		return (ENOBUFS);
	}
	bcopy(addrlo, enm->enm_addrlo, 6);
	bcopy(addrhi, enm->enm_addrhi, 6);
	enm->enm_ac = ac;
	enm->enm_refcount = 1;
	enm->enm_next = ac->ac_multiaddrs;
	ac->ac_multiaddrs = enm;
	ac->ac_multicnt++;
	splx(s);
	/*
	 * Return ENETRESET to inform the driver that the list has changed
	 * and its reception filter should be adjusted accordingly.
	 */
	return (ENETRESET);
}

/*
 * Delete a multicast address record.
 */
int
ether_delmulti(ifr, ac)
	struct ifreq *ifr;
	register struct arpcom *ac;
{
	register struct ether_multi *enm;
	register struct ether_multi **p;
	struct sockaddr_in *sin;
	u_char addrlo[6];
	u_char addrhi[6];
	int s = splimp();

	switch (ifr->ifr_addr.sa_family) {

	case AF_UNSPEC:
		bcopy(ifr->ifr_addr.sa_data, addrlo, 6);
		bcopy(addrlo, addrhi, 6);
		break;

#ifdef INET
	case AF_INET:
		sin = (struct sockaddr_in *)&(ifr->ifr_addr);
		if (sin->sin_addr.s_addr == INADDR_ANY) {
			/*
			 * An IP address of INADDR_ANY means stop listening
			 * to the range of Ethernet multicast addresses used
			 * for IP.
			 */
			bcopy(ether_ipmulticast_min, addrlo, 6);
			bcopy(ether_ipmulticast_max, addrhi, 6);
		}
		else {
			ETHER_MAP_IP_MULTICAST(&sin->sin_addr, addrlo);
			bcopy(addrlo, addrhi, 6);
		}
		break;
#endif

	default:
		splx(s);
		return (EAFNOSUPPORT);
	}

	/*
	 * Look up the address in our list.
	 */
	ETHER_LOOKUP_MULTI(addrlo, addrhi, ac, enm);
	if (enm == NULL) {
		splx(s);
		return (ENXIO);
	}
	if (--enm->enm_refcount != 0) {
		/*
		 * Still some claims to this record.
		 */
		splx(s);
		return (0);
	}
	/*
	 * No remaining claims to this record; unlink and free it.
	 */
	for (p = &enm->enm_ac->ac_multiaddrs;
	     *p != enm;
	     p = &(*p)->enm_next)
		continue;
	*p = (*p)->enm_next;
	free(enm, M_IFMADDR);
	ac->ac_multicnt--;
	splx(s);
	/*
	 * Return ENETRESET to inform the driver that the list has changed
	 * and its reception filter should be adjusted accordingly.
	 */
	return (ENETRESET);
}