if_bridge.c

eCos/RedBoot for勤研ARM AnywhereII(4510) 含全部源代码

	return (c & BRIDGE_RTABLE_MASK);
}

/*
 * Trim the routing table so that we've got a number of routes
 * less than or equal to the maximum.
 */
void
bridge_rttrim(sc)
	struct bridge_softc *sc;
{
	struct bridge_rtnode *n, *p;
	int s, i;

	s = splhigh();
	if (sc->sc_rts == NULL)
		goto done;

	/*
	 * Make sure we have to trim the address table
	 */
	if (sc->sc_brtcnt <= sc->sc_brtmax)
		goto done;

	/*
	 * Force an aging cycle, this might trim enough addresses.
	 */
	splx(s);
	bridge_rtage(sc);
	s = splhigh();

	if (sc->sc_brtcnt <= sc->sc_brtmax)
		goto done;

	for (i = 0; i < BRIDGE_RTABLE_SIZE; i++) {
		n = LIST_FIRST(&sc->sc_rts[i]);
		while (n != NULL) {
			p = LIST_NEXT(n, brt_next);
			if ((n->brt_flags & IFBAF_TYPEMASK) == IFBAF_DYNAMIC) {
				LIST_REMOVE(n, brt_next);
				sc->sc_brtcnt--;
				free(n, M_DEVBUF);
				n = p;
				if (sc->sc_brtcnt <= sc->sc_brtmax)
					goto done;
			}
		}
	}

done:
	if (sc->sc_rts != NULL && sc->sc_brtcnt == 0 &&
	    (sc->sc_if.if_flags & IFF_UP) == 0) {
		free(sc->sc_rts, M_DEVBUF);
		sc->sc_rts = NULL;
	}

	splx(s);
}

/*
 * Perform an aging cycle
 */
void
bridge_rtage(vsc)
	void *vsc;
{
	struct bridge_softc *sc = (struct bridge_softc *)vsc;
	struct bridge_rtnode *n, *p;
	int s, i;

	s = splhigh();
	if (sc->sc_rts == NULL) {
		splx(s);
		return;
	}

	for (i = 0; i < BRIDGE_RTABLE_SIZE; i++) {
		n = LIST_FIRST(&sc->sc_rts[i]);
		while (n != NULL) {
			if ((n->brt_flags & IFBAF_TYPEMASK) == IFBAF_STATIC) {
				n->brt_age = !n->brt_age;
				if (n->brt_age)
					n->brt_age = 0;
				n = LIST_NEXT(n, brt_next);
			} else if (n->brt_age) {
				n->brt_age = 0;
				n = LIST_NEXT(n, brt_next);
			} else {
				p = LIST_NEXT(n, brt_next);
				LIST_REMOVE(n, brt_next);
				sc->sc_brtcnt--;
				free(n, M_DEVBUF);
				n = p;
			}
		}
	}
	splx(s);

	if (sc->sc_brttimeout != 0)
		timeout(bridge_rtage, sc, sc->sc_brttimeout);
}

/*
 * Remove all dynamic addresses from the cache
 */
int
bridge_rtflush(sc, full)
	struct bridge_softc *sc;
	int full;
{
	int s, i;
	struct bridge_rtnode *p, *n;

	s = splhigh();
	if (sc->sc_rts == NULL)
		goto done;

	for (i = 0; i < BRIDGE_RTABLE_SIZE; i++) {
		n = LIST_FIRST(&sc->sc_rts[i]);
		while (n != NULL) {
			if (full ||
			    (n->brt_flags & IFBAF_TYPEMASK) == IFBAF_DYNAMIC) {
				p = LIST_NEXT(n, brt_next);
				LIST_REMOVE(n, brt_next);
				sc->sc_brtcnt--;
				free(n, M_DEVBUF);
				n = p;
			} else
				n = LIST_NEXT(n, brt_next);
		}
	}

	if (sc->sc_brtcnt == 0 && (sc->sc_if.if_flags & IFF_UP) == 0) {
		free(sc->sc_rts, M_DEVBUF);
		sc->sc_rts = NULL;
	}

done:
	splx(s);
	return (0);
}

/*
 * Remove an address from the cache
 */
int
bridge_rtdaddr(sc, ea)
	struct bridge_softc *sc;
	struct ether_addr *ea;
{
	int h, s;
	struct bridge_rtnode *p;

	s = splhigh();
	if (sc->sc_rts == NULL)
		goto done;

	h = bridge_hash(ea);
	p = LIST_FIRST(&sc->sc_rts[h]);
	while (p != NULL) {
		if (bcmp(ea, &p->brt_addr, sizeof(p->brt_addr)) == 0) {
			LIST_REMOVE(p, brt_next);
			sc->sc_brtcnt--;
			free(p, M_DEVBUF);
			if (sc->sc_brtcnt == 0 &&
			    (sc->sc_if.if_flags & IFF_UP) == 0) {
				free(sc->sc_rts, M_DEVBUF);
				sc->sc_rts = NULL;
			}
			splx(s);
			return (0);
		}
		p = LIST_NEXT(p, brt_next);
	}

done:
	splx(s);
	return (ENOENT);
}
/*
 * Delete routes to a specific interface member.
 */
void
bridge_rtdelete(sc, ifp, dynonly)
	struct bridge_softc *sc;
	struct ifnet *ifp;
{
	int i, s;
	struct bridge_rtnode *n, *p;

	s = splhigh();
	if (sc->sc_rts == NULL)
		goto done;

	/*
	 * Loop through all of the hash buckets and traverse each
	 * chain looking for routes to this interface.
	 */
	for (i = 0; i < BRIDGE_RTABLE_SIZE; i++) {
		n = LIST_FIRST(&sc->sc_rts[i]);
		while (n != NULL) {
			if (n->brt_if == ifp) {		/* found one */
				p = LIST_NEXT(n, brt_next);
				LIST_REMOVE(n, brt_next);
				sc->sc_brtcnt--;
				free(n, M_DEVBUF);
				n = p;
			} else
				n = LIST_NEXT(n, brt_next);
		}
	}
	if (sc->sc_brtcnt == 0 && (sc->sc_if.if_flags & IFF_UP) == 0) {
		free(sc->sc_rts, M_DEVBUF);
		sc->sc_rts = NULL;
	}

done:
	splx(s);
}

/*
 * Gather all of the routes for this interface.
 */
int
bridge_rtfind(sc, baconf)
	struct bridge_softc *sc;
	struct ifbaconf *baconf;
{
	int i, s, error = 0;
	u_int32_t cnt = 0;
	struct bridge_rtnode *n;
	struct ifbareq bareq;

	s = splhigh();

	if (sc->sc_rts == NULL || baconf->ifbac_len == 0)
		goto done;

	for (i = 0, cnt = 0; i < BRIDGE_RTABLE_SIZE; i++) {
		n = LIST_FIRST(&sc->sc_rts[i]);
		while (n != NULL) {
			if (baconf->ifbac_len <
			    (cnt + 1) * sizeof(struct ifbareq))
				goto done;
			bcopy(sc->sc_if.if_xname, bareq.ifba_name,
			    sizeof(bareq.ifba_name));
			bcopy(n->brt_if->if_xname, bareq.ifba_ifsname,
			    sizeof(bareq.ifba_ifsname));
			bcopy(&n->brt_addr, &bareq.ifba_dst,
			    sizeof(bareq.ifba_dst));
			bareq.ifba_age = n->brt_age;
			bareq.ifba_flags = n->brt_flags;
			error = copyout((caddr_t)&bareq,
		    	    (caddr_t)(baconf->ifbac_req + cnt), sizeof(bareq));
			if (error)
				goto done;
			n = LIST_NEXT(n, brt_next);
			cnt++;
		}
	}
done:
	baconf->ifbac_len = cnt * sizeof(struct ifbareq);
	splx(s);
	return (error);
}

/*
 * Block non-ip frames:
 * Returns 0 if frame is ip, and 1 if it should be dropped.
 */
int
bridge_blocknonip(eh, m)
	struct ether_header *eh;
	struct mbuf *m;
{
	struct snap snap;
	u_int16_t etype;

	if (m->m_pkthdr.len < sizeof(struct ether_header))
		return (1);

	etype = ntohs(eh->ether_type);
	switch (etype) {
	case ETHERTYPE_ARP:
	case ETHERTYPE_REVARP:
	case ETHERTYPE_IP:
	case ETHERTYPE_IPV6:
		return (0);
	}

	if (etype > ETHERMTU)
		return (1);

	if (m->m_pkthdr.len <
	    (sizeof(struct ether_header) + sizeof(struct snap)))
		return (1);

	m_copydata(m, sizeof(struct ether_header), sizeof(struct snap),
	    (caddr_t)&snap);

	etype = ntohs(snap.type);
	if (snap.dsap == LLC_SNAP_LSAP && snap.ssap == LLC_SNAP_LSAP &&
	    snap.control == LLC_UI &&
	    snap.org[0] == 0 && snap.org[1] == 0 && snap.org[2] == 0 &&
	    (etype == ETHERTYPE_ARP ||
	     etype == ETHERTYPE_REVARP ||
	     etype == ETHERTYPE_IP ||
	     etype == ETHERTYPE_IPV6)) {
		return (0);
	}

	return (1);
}

u_int8_t
bridge_filterrule(n, eh)
	struct brl_node *n;
	struct ether_header *eh;
{
	u_int8_t flags;

	for (; n != NULL; n = SIMPLEQ_NEXT(n, brl_next)) {
		flags = n->brl_flags & (BRL_FLAG_SRCVALID|BRL_FLAG_DSTVALID);
		if (flags == 0)
			return (n->brl_action);
		if (flags == (BRL_FLAG_SRCVALID|BRL_FLAG_DSTVALID)) {
			if (bcmp(eh->ether_shost, &n->brl_src, ETHER_ADDR_LEN))
				continue;
			if (bcmp(eh->ether_dhost, &n->brl_src, ETHER_ADDR_LEN))
				continue;
			return (n->brl_action);
		}
		if (flags == BRL_FLAG_SRCVALID) {
			if (bcmp(eh->ether_shost, &n->brl_src, ETHER_ADDR_LEN))
				continue;
			return (n->brl_action);
		}
		if (flags == BRL_FLAG_DSTVALID) {
			if (bcmp(eh->ether_dhost, &n->brl_dst, ETHER_ADDR_LEN))
				continue;
			return (n->brl_action);
		}
	}
	return (BRL_ACTION_PASS);
}

int
bridge_addrule(bif, req, out)
	struct bridge_iflist *bif;
	struct ifbrlreq *req;
	int out;
{
	struct brl_node *n;

	n = (struct brl_node *)malloc(sizeof(struct brl_node), M_DEVBUF, M_NOWAIT);
	if (n == NULL)
		return (ENOMEM);
	bcopy(&req->ifbr_src, &n->brl_src, sizeof(struct ether_addr));
	bcopy(&req->ifbr_dst, &n->brl_dst, sizeof(struct ether_addr));
	n->brl_action = req->ifbr_action;
	n->brl_flags = req->ifbr_flags;
	if (out) {
		n->brl_flags &= ~BRL_FLAG_IN;
		n->brl_flags |= BRL_FLAG_OUT;
		SIMPLEQ_INSERT_TAIL(&bif->bif_brlout, n, brl_next);
	} else {
		n->brl_flags &= ~BRL_FLAG_OUT;
		n->brl_flags |= BRL_FLAG_IN;
		SIMPLEQ_INSERT_TAIL(&bif->bif_brlin, n, brl_next);
	}
	return (0);
}

int
bridge_flushrule(bif)
	struct bridge_iflist *bif;
{
	struct brl_node *p, *q;

	p = SIMPLEQ_FIRST(&bif->bif_brlin);
	while (p != NULL) {
		q = SIMPLEQ_NEXT(p, brl_next);
		SIMPLEQ_REMOVE_HEAD(&bif->bif_brlin, p, brl_next);
		free(p, M_DEVBUF);
		p = q;
	}
	p = SIMPLEQ_FIRST(&bif->bif_brlout);
	while (p != NULL) {
		q = SIMPLEQ_NEXT(p, brl_next);
		SIMPLEQ_REMOVE_HEAD(&bif->bif_brlout, p, brl_next);
		free(p, M_DEVBUF);
		p = q;
	}
	return (0);
}

#if defined(INET) && (defined(IPFILTER) || defined(IPFILTER_LKM))

/*
 * Maximum sized IP header
 */
union maxip {
	struct ip ip;
	u_int32_t _padding[16];
};

/*
 * Filter IP packets by peeking into the ethernet frame.  This violates
 * the ISO model, but allows us to act as a IP filter at the data link
 * layer.  As a result, most of this code will look familiar to those
 * who've read net/if_ethersubr.c and netinet/ip_input.c
 */
struct mbuf *
bridge_filter(sc, ifp, eh, m)
	struct bridge_softc *sc;
	struct ifnet *ifp;
	struct ether_header *eh;
	struct mbuf *m;
{
	struct snap snap;
	int hassnap = 0;
	struct ip *ip;
	int hlen;

	if (fr_checkp == NULL)
		return (m);

	if (eh->ether_type != htons(ETHERTYPE_IP)) {
		if (eh->ether_type > ETHERMTU ||
		    m->m_pkthdr.len < (sizeof(struct snap) +
		    sizeof(struct ether_header)))
			return (m);

		m_copydata(m, sizeof(struct ether_header),
		    sizeof(struct snap), (caddr_t)&snap);

		if (snap.dsap != LLC_SNAP_LSAP || snap.ssap != LLC_SNAP_LSAP ||
		    snap.control != LLC_UI ||
		    snap.org[0] != 0 || snap.org[1] != 0 || snap.org[2] ||
		    snap.type != htons(ETHERTYPE_IP))
			return (m);
		hassnap = 1;
	}

	m_adj(m, sizeof(struct ether_header));
	if (hassnap)
		m_adj(m, sizeof(struct snap));

	if (m->m_pkthdr.len < sizeof(struct ip))
		goto dropit;

	/* Copy minimal header, and drop invalids */
	if (m->m_len < sizeof(struct ip) &&
	    (m = m_pullup(m, sizeof(struct ip))) == NULL)
		return (NULL);
	ip = mtod(m, struct ip *);

	if (ip->ip_v != IPVERSION)
		goto dropit;

	hlen = ip->ip_hl << 2;	/* get whole header length */
	if (hlen < sizeof(struct ip))
		goto dropit;
	if (hlen > m->m_len) {
		if ((m = m_pullup(m, sizeof(struct ip))) == NULL)
			return (NULL);
		ip = mtod(m, struct ip *);
	}

	if ((ip->ip_sum = in_cksum(m, hlen)) != 0)
		goto dropit;

	NTOHS(ip->ip_len);
	if (ip->ip_len < hlen)
		goto dropit;
	NTOHS(ip->ip_id);
	NTOHS(ip->ip_off);

	if (m->m_pkthdr.len < ip->ip_len)
		goto dropit;
	if (m->m_pkthdr.len > ip->ip_len) {
		if (m->m_len == m->m_pkthdr.len) {
			m->m_len = ip->ip_len;
			m->m_pkthdr.len = ip->ip_len;
		} else
			m_adj(m, ip->ip_len - m->m_pkthdr.len);
	}

	/* Finally, we get to filter the packet! */
	if (fr_checkp && (*fr_checkp)(ip, hlen, ifp, 0, &m))
		return (NULL);

	/* Rebuild the IP header */
	if (m->m_len < hlen && ((m = m_pullup(m, hlen)) == NULL))
		return (NULL);
	if (m->m_len < sizeof(struct ip))
		goto dropit;
	ip = mtod(m, struct ip *);
	HTONS(ip->ip_len);
	HTONS(ip->ip_id);
	HTONS(ip->ip_off);
	ip->ip_sum = in_cksum(m, hlen);

	/* Reattach SNAP header */
	if (hassnap) {
		M_PREPEND(m, sizeof(snap), M_DONTWAIT);
		if (m == NULL)
			goto dropit;
		bcopy(&snap, mtod(m, caddr_t), sizeof(snap));
	}

	/* Reattach ethernet header */
	M_PREPEND(m, sizeof(*eh), M_DONTWAIT);
	if (m == NULL)
		goto dropit;
	bcopy(eh, mtod(m, caddr_t), sizeof(*eh));

	return (m);

dropit:
	if (m != NULL)
		m_freem(m);
	return (NULL);
}
#endif

int
ifpromisc(ifp, pswitch)
	struct ifnet *ifp;
	int pswitch;
{
	struct ifreq ifr;

	if (pswitch) {
		/*
		 * If the device is not configured up, we cannot put it in
		 * promiscuous mode.
		 */
		if ((ifp->if_flags & IFF_UP) == 0)
			return (ENETDOWN);
		if (ifp->if_pcount++ != 0)
			return (0);
		ifp->if_flags |= IFF_PROMISC;
	} else {
		if (--ifp->if_pcount > 0)
			return (0);
		ifp->if_flags &= ~IFF_PROMISC;
		/*
		 * If the device is not configured up, we should not need to
		 * turn off promiscuous mode (device should have turned it
		 * off when interface went down; and will look at IFF_PROMISC
		 * again next time interface comes up).
		 */
		if ((ifp->if_flags & IFF_UP) == 0)
			return (0);
	}
	ifr.ifr_flags = ifp->if_flags;
	return ((*ifp->if_ioctl)(ifp, SIOCSIFFLAGS, (caddr_t)&ifr));
}

int
bridge_ifenqueue(sc, ifp, m)
        struct bridge_softc *sc;
        struct ifnet *ifp;
        struct mbuf *m;
{
        int error, len;
        short mflags;

        len = m->m_pkthdr.len;
        mflags = m->m_flags;
        IFQ_ENQUEUE(&ifp->if_snd, m, NULL, error);
        if (error) {
                sc->sc_if.if_oerrors++;
                return (error);
        }
        sc->sc_if.if_opackets++;
        sc->sc_if.if_obytes += len;
        ifp->if_obytes += len;
        if (mflags & M_MCAST)
                ifp->if_omcasts++;
        if ((ifp->if_flags & IFF_OACTIVE) == 0)
                (*ifp->if_start)(ifp);
                                                                                                           return (0);
}