/* $OpenBSD: if_bridge.c,v 1.4 1999/03/05 21:10:52 jason Exp $ */ /* * Copyright (c) 1999 Jason L. Wright (jason@thought.net) * 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 Jason L. Wright * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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. */ #include "bridge.h" #if NBRIDGE > 0 #include #include #include #include #include #include #include #include #include #include #include #include #ifdef INET #include #include #include #include #include #ifdef IPFILTER #include #include #endif #endif #include #ifndef BRIDGE_RTABLE_SIZE #define BRIDGE_RTABLE_SIZE 1024 #endif #define BRIDGE_RTABLE_MASK (BRIDGE_RTABLE_SIZE - 1) /* * Maximum number of addresses to cache */ #ifndef BRIDGE_RTABLE_MAX #define BRIDGE_RTABLE_MAX 100 #endif /* * Timeout (in seconds) for entries learned dynamically */ #ifndef BRIDGE_RTABLE_TIMEOUT #define BRIDGE_RTABLE_TIMEOUT 30 #endif extern int ifqmaxlen; /* * Bridge interface list */ struct bridge_iflist { LIST_ENTRY(bridge_iflist) next; /* next in list */ struct ifnet *ifp; /* member interface */ u_int32_t bif_flags; /* member flags */ }; /* * Bridge route node */ struct bridge_rtnode { LIST_ENTRY(bridge_rtnode) brt_next; /* next in list */ struct ifnet *brt_if; /* destination ifs */ u_int32_t brt_age; /* age counter */ struct ether_addr brt_addr; /* dst addr */ }; /* * Software state for each bridge */ struct bridge_softc { struct ifnet sc_if; /* the interface */ u_int32_t sc_brtmax; /* max # addresses */ u_int32_t sc_brtcnt; /* current # addrs */ u_int32_t sc_brttimeout; /* current # addrs */ LIST_HEAD(, bridge_iflist) sc_iflist; /* interface list */ LIST_HEAD(bridge_rthead, bridge_rtnode) *sc_rts;/* hash table */ }; struct bridge_softc bridgectl[NBRIDGE]; void bridgeattach __P((int)); int bridge_ioctl __P((struct ifnet *, u_long, caddr_t)); void bridge_start __P((struct ifnet *)); struct mbuf * bridge_broadcast __P((struct bridge_softc *sc, struct ifnet *, struct ether_header *, struct mbuf *)); void bridge_stop __P((struct bridge_softc *)); void bridge_init __P((struct bridge_softc *)); int bridge_bifconf __P((struct bridge_softc *, struct ifbifconf *)); int bridge_rtfind __P((struct bridge_softc *, struct ifbaconf *)); void bridge_rtage __P((void *)); void bridge_rttrim __P((struct bridge_softc *)); void bridge_rtdelete __P((struct bridge_softc *, struct ifnet *)); struct ifnet * bridge_rtupdate __P((struct bridge_softc *, struct ether_addr *, struct ifnet *ifp)); struct ifnet * bridge_rtlookup __P((struct bridge_softc *, struct ether_addr *)); u_int32_t bridge_hash __P((struct ether_addr *)); #define ETHERADDR_IS_IP_MCAST(a) \ /* struct etheraddr *a; */ \ ((a)->ether_addr_octet[0] == 0x01 && \ (a)->ether_addr_octet[1] == 0x00 && \ (a)->ether_addr_octet[2] == 0x5e) #if defined(INET) && (defined(IPFILTER) || defined(IPFILTER_LKM)) /* * Filter hooks */ #define BRIDGE_FILTER_PASS 0 #define BRIDGE_FILTER_DROP 1 int bridge_filter __P((struct bridge_softc *, struct ifnet *, struct ether_header *, struct mbuf *)); #endif void bridgeattach(unused) int unused; { int i; struct ifnet *ifp; for (i = 0; i < NBRIDGE; i++) { bridgectl[i].sc_brtmax = BRIDGE_RTABLE_MAX; bridgectl[i].sc_brttimeout = BRIDGE_RTABLE_TIMEOUT; LIST_INIT(&bridgectl[i].sc_iflist); ifp = &bridgectl[i].sc_if; sprintf(ifp->if_xname, "bridge%d", i); ifp->if_softc = &bridgectl[i]; ifp->if_mtu = ETHERMTU; ifp->if_ioctl = bridge_ioctl; ifp->if_output = bridge_output; ifp->if_start = bridge_start; ifp->if_type = IFT_PROPVIRTUAL; ifp->if_snd.ifq_maxlen = ifqmaxlen; ifp->if_hdrlen = sizeof(struct ether_header); if_attach(ifp); } } int bridge_ioctl(ifp, cmd, data) struct ifnet *ifp; u_long cmd; caddr_t data; { struct proc *prc = curproc; /* XXX */ struct ifnet *ifs; struct bridge_softc *sc = (struct bridge_softc *)ifp->if_softc; struct ifbreq *req = (struct ifbreq *)data; struct ifbaconf *baconf = (struct ifbaconf *)data; struct ifbcachereq *bcachereq = (struct ifbcachereq *)data; struct ifbifconf *bifconf = (struct ifbifconf *)data; struct ifbcachetoreq *bcacheto = (struct ifbcachetoreq *)data; int error = 0, s; struct bridge_iflist *p; s = splimp(); switch(cmd) { case SIOCBRDGADD: if ((error = suser(prc->p_ucred, &prc->p_acflag)) != 0) break; ifs = ifunit(req->ifbr_ifsname); if (ifs == NULL) { /* no such interface */ error = ENOENT; break; } if (ifs->if_bridge == (caddr_t)sc) { error = EEXIST; break; } if (ifs->if_bridge != NULL) { error = EBUSY; break; } if (ifs->if_type != IFT_ETHER) { error = EINVAL; break; } error = ifpromisc(ifs, 1); if (error != 0) break; p = (struct bridge_iflist *) malloc( sizeof(struct bridge_iflist), M_DEVBUF, M_NOWAIT); if (p == NULL) { /* list alloc failed */ error = ENOMEM; ifpromisc(ifs, 0); /* decr promisc cnt */ break; } p->ifp = ifs; LIST_INSERT_HEAD(&sc->sc_iflist, p, next); ifs->if_bridge = (caddr_t)sc; break; case SIOCBRDGDEL: if ((error = suser(prc->p_ucred, &prc->p_acflag)) != 0) break; p = LIST_FIRST(&sc->sc_iflist); while (p != NULL) { if (strncmp(p->ifp->if_xname, req->ifbr_ifsname, sizeof(p->ifp->if_xname)) == 0) { p->ifp->if_bridge = NULL; error = ifpromisc(p->ifp, 0); LIST_REMOVE(p, next); bridge_rtdelete(sc, p->ifp); free(p, M_DEVBUF); break; } p = LIST_NEXT(p, next); } if (p == NULL) { error = ENOENT; break; } break; case SIOCBRDGIFS: error = bridge_bifconf(sc, bifconf); break; case SIOCBRDGRTS: if ((ifp->if_flags & IFF_RUNNING) == 0) { error = ENETDOWN; break; } error = bridge_rtfind(sc, baconf); break; case SIOCBRDGGCACHE: bcachereq->ifbc_size = sc->sc_brtmax; break; case SIOCBRDGSCACHE: if ((error = suser(prc->p_ucred, &prc->p_acflag)) != 0) break; sc->sc_brtmax = bcachereq->ifbc_size; bridge_rttrim(sc); break; case SIOCBRDGSTO: if ((error = suser(prc->p_ucred, &prc->p_acflag)) != 0) break; sc->sc_brttimeout = bcacheto->ifbct_time; untimeout(bridge_rtage, sc); if (bcacheto->ifbct_time != 0) timeout(bridge_rtage, sc, sc->sc_brttimeout); break; case SIOCBRDGGTO: bcacheto->ifbct_time = sc->sc_brttimeout; break; case SIOCSIFFLAGS: if ((ifp->if_flags & IFF_UP) == IFF_UP) bridge_init(sc); if ((ifp->if_flags & IFF_UP) == 0) bridge_stop(sc); break; default: error = EINVAL; } splx(s); return (error); } int bridge_bifconf(sc, bifc) struct bridge_softc *sc; struct ifbifconf *bifc; { struct bridge_iflist *p; u_int32_t total, i; int error; struct ifbreq breq; p = LIST_FIRST(&sc->sc_iflist); while (p != NULL) { total++; p = LIST_NEXT(p, next); } if (bifc->ifbic_len == 0) { bifc->ifbic_len = total * sizeof(struct ifbreq); return (0); } p = LIST_FIRST(&sc->sc_iflist); i = 0; while (p != NULL && bifc->ifbic_len > sizeof(breq)) { strncpy(breq.ifbr_name, sc->sc_if.if_xname, sizeof (breq.ifbr_name)); breq.ifbr_name[sizeof(breq.ifbr_name)-1] = '\0'; strncpy(breq.ifbr_ifsname, p->ifp->if_xname, sizeof (breq.ifbr_ifsname)); breq.ifbr_ifsname[sizeof(breq.ifbr_ifsname)-1] = '\0'; breq.ifbr_ifsflags = p->bif_flags; error = copyout((caddr_t)&breq, (caddr_t)(bifc->ifbic_req + i), sizeof(breq)); if (error) { bifc->ifbic_len = i * sizeof(breq); return (error); } p = LIST_NEXT(p, next); i++; bifc->ifbic_len -= sizeof(breq); } bifc->ifbic_len = i * sizeof(breq); return (0); } void bridge_init(sc) struct bridge_softc *sc; { struct ifnet *ifp = &sc->sc_if; int i; int s; if ((ifp->if_flags & IFF_RUNNING) == IFF_RUNNING) return; s = splhigh(); if (sc->sc_rts == NULL) { sc->sc_rts = (struct bridge_rthead *)malloc( BRIDGE_RTABLE_SIZE * (sizeof(struct bridge_rthead)), M_DEVBUF, M_NOWAIT); if (sc->sc_rts == NULL) { splx(s); return; } for (i = 0; i < BRIDGE_RTABLE_SIZE; i++) { LIST_INIT(&sc->sc_rts[i]); } } ifp->if_flags |= IFF_RUNNING; splx(s); if (sc->sc_brttimeout != 0) timeout(bridge_rtage, sc, sc->sc_brttimeout * hz); } /* * Stop the bridge and deallocate the routing table. */ void bridge_stop(sc) struct bridge_softc *sc; { struct ifnet *ifp = &sc->sc_if; struct bridge_rtnode *n, *p; int i, s; /* * If we're not running, there's nothing to do. */ if ((ifp->if_flags & IFF_RUNNING) == 0) return; untimeout(bridge_rtage, sc); /* * Free the routing table, if necessary. */ if (sc->sc_rts != NULL) { s = splhigh(); for (i = 0; i < BRIDGE_RTABLE_SIZE; i++) { n = LIST_FIRST(&sc->sc_rts[i]); while (n != NULL) { p = LIST_NEXT(n, brt_next); LIST_REMOVE(n, brt_next); free(n, M_DEVBUF); sc->sc_brtcnt--; n = p; } } free(sc->sc_rts, M_DEVBUF); sc->sc_rts = NULL; splx(s); } ifp->if_flags &= ~IFF_RUNNING; } /* * Send output from the bridge. The mbuf has the ethernet header * already attached. We must free the mbuf before exitting. */ int bridge_output(ifp, m, sa, rt) struct ifnet *ifp; struct mbuf *m; struct sockaddr *sa; struct rtentry *rt; { struct ether_header *eh; struct ifnet *dst_if; struct ether_addr *src, *dst; struct arpcom *ac = (struct arpcom *)ifp; struct bridge_softc *sc; struct bridge_iflist *p; struct mbuf *mc; int s; if (m->m_len < sizeof(*eh)) { m = m_pullup(m, sizeof(*eh)); if (m == NULL) return (0); } eh = mtod(m, struct ether_header *); dst = (struct ether_addr *)&eh->ether_dhost[0]; src = (struct ether_addr *)&eh->ether_shost[0]; sc = (struct bridge_softc *)ifp->if_bridge; s = splimp(); /* * If the packet is a broadcast or we don't know a better way to * get there, we must broadcast with header rewriting. */ dst_if = bridge_rtlookup(sc, dst); if (dst_if == NULL || eh->ether_dhost[0] & 1) { for (p = LIST_FIRST(&sc->sc_iflist); p != NULL; p = LIST_NEXT(p, next)) { if ((p->ifp->if_flags & IFF_RUNNING) == 0) continue; if (IF_QFULL(&p->ifp->if_snd)) { sc->sc_if.if_oerrors++; continue; } /* * Make a full copy of the packet (sigh) */ mc = m_copym2(m, 0, M_COPYALL, M_NOWAIT); if (mc == NULL) { sc->sc_if.if_oerrors++; continue; } /* * If packet does not have a multicast or broadcast * destination, rewrite the header to contain * the current interface's address. */ if ((eh->ether_shost[0] & 1) == 0) { struct arpcom *cac = (struct arpcom *)p->ifp; struct ether_header *ceh; struct ether_addr *csrc; if (mc->m_len < sizeof(*ceh)) { mc = m_pullup(mc, sizeof(*ceh)); if (mc == NULL) continue; } ceh = mtod(mc, struct ether_header *); csrc = (struct ether_addr *) &ceh->ether_shost[0]; bcopy(cac->ac_enaddr, csrc, ETHER_ADDR_LEN); } sc->sc_if.if_opackets++; sc->sc_if.if_obytes += m->m_pkthdr.len; IF_ENQUEUE(&p->ifp->if_snd, mc); if ((p->ifp->if_flags & IFF_OACTIVE) == 0) (*p->ifp->if_start)(p->ifp); } m_freem(m); splx(s); return (0); } bcopy(ac->ac_enaddr, src, ETHER_ADDR_LEN); if ((dst_if->if_flags & IFF_RUNNING) == 0) { m_freem(m); splx(s); return (0); } if (IF_QFULL(&dst_if->if_snd)) { sc->sc_if.if_oerrors++; m_freem(m); splx(s); return (0); } sc->sc_if.if_opackets++; sc->sc_if.if_obytes += m->m_pkthdr.len; IF_ENQUEUE(&dst_if->if_snd, m); if ((dst_if->if_flags & IFF_OACTIVE) == 0) (*dst_if->if_start)(dst_if); splx(s); return (0); } /* * Start output on the bridge. This function should never be called. */ void bridge_start(ifp) struct ifnet *ifp; { } /* * Receive input from an interface. Rebroadcast if necessary to other * bridge members. */ struct mbuf * bridge_input(ifp, eh, m) struct ifnet *ifp; struct ether_header *eh; struct mbuf *m; { struct bridge_softc *sc; struct arpcom *ac; struct ether_addr *dst, *src; struct ifnet *dst_if; int s; /* * Make sure this interface is a bridge member. */ if (ifp == NULL || ifp->if_bridge == NULL || m == NULL) return (m); sc = (struct bridge_softc *)ifp->if_bridge; s = splimp(); if ((sc->sc_if.if_flags & IFF_RUNNING) == 0) { splx(s); return (m); } sc->sc_if.if_lastchange = time; sc->sc_if.if_ipackets++; sc->sc_if.if_ibytes += m->m_pkthdr.len; /* * See if the destination of this frame matches the interface * it came in on. If so, we don't need to do anything. */ ac = (struct arpcom *)ifp; if (bcmp(ac->ac_enaddr, eh->ether_dhost, ETHER_ADDR_LEN) == 0) { splx(s); return (m); } dst = (struct ether_addr *)&eh->ether_dhost[0]; src = (struct ether_addr *)&eh->ether_shost[0]; /* * If source address is not broadcast or multicast, record * it's address. */ if ((eh->ether_shost[0] & 1) == 0 && !(eh->ether_shost[0] == 0 && eh->ether_shost[1] == 0 && eh->ether_shost[2] == 0 && eh->ether_shost[3] == 0 && eh->ether_shost[4] == 0 && eh->ether_shost[5] == 0)) bridge_rtupdate(sc, src, ifp); /* * If packet is unicast, destined for someone on "this" * side of the bridge, drop it. */ dst_if = bridge_rtlookup(sc, dst); if ((m->m_flags & (M_BCAST|M_MCAST)) == 0 && dst_if == ifp) { m_freem(m); splx(s); return (NULL); } /* * Multicast packets get handled a little differently: * If interface is: * -link0,-link1 (default) Forward all multicast as broadcast. * -link0,link1 Drop non-IP multicast, forward as broadcast * IP multicast. * link0,-link1 Drop IP multicast, forward as broadcast * non-IP multicast. * link0,link1 Drop all multicast. */ if (m->m_flags & M_MCAST) { if ((sc->sc_if.if_flags & (IFF_LINK0|IFF_LINK1)) == (IFF_LINK0|IFF_LINK1)) { splx(s); return (m); } if (sc->sc_if.if_flags & IFF_LINK0 && ETHERADDR_IS_IP_MCAST(dst)) { splx(s); return (m); } if (sc->sc_if.if_flags & IFF_LINK1 && !ETHERADDR_IS_IP_MCAST(dst)) { splx(s); return (m); } } #if defined(INET) && (defined(IPFILTER) || defined(IPFILTER_LKM)) /* * Pass the packet to the ip filtering code and drop * here if necessary. */ if (bridge_filter(sc, ifp, eh, m) == BRIDGE_FILTER_DROP) { if (m->m_flags & (M_BCAST|M_MCAST)) { /* * Broadcasts should be passed down if filtered * by the bridge, so that they can be filtered * by the interface itself. */ splx(s); return (m); } m_freem(m); splx(s); return (NULL); } #endif /* * If the packet is a multicast or broadcast, then forward it * and pass it up to our higher layers. */ if (m->m_flags & (M_BCAST|M_MCAST)) { ifp->if_imcasts++; m = bridge_broadcast(sc, ifp, eh, m); splx(s); return (m); } /* * If sucessful lookup, forward packet to that interface only. */ if (dst_if != NULL) { if ((dst_if->if_flags & IFF_RUNNING) == 0) { m_freem(m); splx(s); return (NULL); } if (IF_QFULL(&dst_if->if_snd)) { sc->sc_if.if_oerrors++; m_freem(m); splx(s); return (NULL); } M_PREPEND(m, sizeof(*eh), M_DONTWAIT); if (m == NULL) { sc->sc_if.if_oerrors++; return (NULL); } *mtod(m, struct ether_header *) = *eh; sc->sc_if.if_opackets++; sc->sc_if.if_obytes += m->m_pkthdr.len; IF_ENQUEUE(&dst_if->if_snd, m); if ((dst_if->if_flags & IFF_OACTIVE) == 0) (*dst_if->if_start)(dst_if); splx(s); return (NULL); } /* * Packet must be forwarded to all interfaces. */ m = bridge_broadcast(sc, ifp, eh, m); splx(s); return (m); } /* * Send a frame to all interfaces that are members of the bridge * (except the one it came in on). This code assumes that it is * running at splnet or higher. */ struct mbuf * bridge_broadcast(sc, ifp, eh, m) struct bridge_softc *sc; struct ifnet *ifp; struct ether_header *eh; struct mbuf *m; { struct bridge_iflist *p; struct mbuf *mc; /* * Tack on ethernet header */ M_PREPEND(m, sizeof(*eh), M_DONTWAIT); if (m == NULL) return (NULL); *mtod(m, struct ether_header *) = *eh; for (p = LIST_FIRST(&sc->sc_iflist); p; p = LIST_NEXT(p, next)) { /* * Don't retransmit out of the same interface where * the packet was received from. */ if (p->ifp->if_index == ifp->if_index) continue; if ((p->ifp->if_flags & IFF_RUNNING) == 0) continue; if (IF_QFULL(&p->ifp->if_snd)) { sc->sc_if.if_oerrors++; continue; } mc = m_copym(m, 0, M_COPYALL, M_DONTWAIT); if (mc == NULL) { sc->sc_if.if_oerrors++; continue; } sc->sc_if.if_opackets++; sc->sc_if.if_obytes += m->m_pkthdr.len; if ((eh->ether_shost[0] & 1) == 0) ifp->if_omcasts++; IF_ENQUEUE(&p->ifp->if_snd, mc); if ((p->ifp->if_flags & IFF_OACTIVE) == 0) (*p->ifp->if_start)(p->ifp); } m_adj(m, sizeof(struct ether_header)); return (m); } struct ifnet * bridge_rtupdate(sc, ea, ifp) struct bridge_softc *sc; struct ether_addr *ea; struct ifnet *ifp; { struct bridge_rtnode *p, *q; u_int32_t h; int s, dir; s = splhigh(); if (sc->sc_rts == NULL) { splx(s); return (NULL); } h = bridge_hash(ea); p = LIST_FIRST(&sc->sc_rts[h]); if (p == NULL) { if (sc->sc_brtcnt >= sc->sc_brtmax) { splx(s); return (NULL); } p = (struct bridge_rtnode *) malloc(sizeof(struct bridge_rtnode), M_DEVBUF, M_NOWAIT); if (p == NULL) { splx(s); return (NULL); } bcopy(ea, &p->brt_addr, sizeof(p->brt_addr)); p->brt_if = ifp; p->brt_age = 1; LIST_INSERT_HEAD(&sc->sc_rts[h], p, brt_next); sc->sc_brtcnt++; splx(s); return (ifp); } do { q = p; p = LIST_NEXT(p, brt_next); dir = bcmp(ea, &q->brt_addr, sizeof(q->brt_addr)); if (dir == 0) { q->brt_if = ifp; q->brt_age = 1; splx(s); return (ifp); } if (dir > 0) { if (sc->sc_brtcnt >= sc->sc_brtmax) { splx(s); return (NULL); } p = (struct bridge_rtnode *) malloc(sizeof(struct bridge_rtnode), M_DEVBUF, M_NOWAIT); if (p == NULL) { splx(s); return (NULL); } bcopy(ea, &p->brt_addr, sizeof(p->brt_addr)); p->brt_if = ifp; p->brt_age = 1; LIST_INSERT_BEFORE(q, p, brt_next); sc->sc_brtcnt++; splx(s); return (ifp); } if (p == NULL) { if (sc->sc_brtcnt >= sc->sc_brtmax) { splx(s); return (NULL); } p = (struct bridge_rtnode *) malloc(sizeof(struct bridge_rtnode), M_DEVBUF, M_NOWAIT); if (p == NULL) { splx(s); return (NULL); } bcopy(ea, &p->brt_addr, sizeof(p->brt_addr)); p->brt_if = ifp; p->brt_age = 1; LIST_INSERT_AFTER(q, p, brt_next); sc->sc_brtcnt++; splx(s); return (ifp); } } while (p != NULL); splx(s); return (NULL); } struct ifnet * bridge_rtlookup(sc, ea) struct bridge_softc *sc; struct ether_addr *ea; { struct bridge_rtnode *p; u_int32_t h; int s, dir; /* * Lock out everything else */ s = splhigh(); if (sc->sc_rts == NULL) { splx(s); return (NULL); } h = bridge_hash(ea); p = LIST_FIRST(&sc->sc_rts[h]); while (p != NULL) { dir = bcmp(ea, &p->brt_addr, sizeof(p->brt_addr)); if (dir == 0) { splx(s); return (p->brt_if); } if (dir > 0) { splx(s); return (NULL); } p = LIST_NEXT(p, brt_next); } splx(s); return (NULL); } /* * The following hash function is adapted from 'Hash Functions' by Bob Jenkins * ("Algorithm Alley", Dr. Dobbs Journal, September 1997). * "You may use this code any way you wish, private, educational, or * commercial. It's free." */ #define mix(a,b,c) \ do { \ a -= b; a -= c; a ^= (c >> 13); \ b -= c; b -= a; b ^= (a << 8); \ c -= a; c -= b; c ^= (b >> 13); \ a -= b; a -= c; a ^= (c >> 12); \ b -= c; b -= a; b ^= (a << 16); \ c -= a; c -= b; c ^= (b >> 5); \ a -= b; a -= c; a ^= (c >> 3); \ b -= c; b -= a; b ^= (a << 10); \ c -= a; c -= b; c ^= (b >> 15); \ } while(0) u_int32_t bridge_hash(addr) struct ether_addr *addr; { u_int32_t a = 0x9e3779b9, b = 0x9e3779b9, c = 0xdeadbeef; b += addr->ether_addr_octet[5] << 8; b += addr->ether_addr_octet[4]; a += addr->ether_addr_octet[3] << 24; a += addr->ether_addr_octet[2] << 16; a += addr->ether_addr_octet[1] << 8; a += addr->ether_addr_octet[0]; mix(a, b, c); 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) { splx(s); return; } /* * Make sure we have to trim the address table */ if (sc->sc_brtcnt <= sc->sc_brtmax) { splx(s); return; } /* * Force an aging cycle, this might trim enough addresses. */ splx(s); bridge_rtage(sc); s = splhigh(); if (sc->sc_brtcnt <= sc->sc_brtmax) { splx(s); return; } for (i = 0; i < BRIDGE_RTABLE_SIZE; i++) { n = LIST_FIRST(&sc->sc_rts[i]); while (n != NULL) { p = LIST_NEXT(n, brt_next); LIST_REMOVE(n, brt_next); sc->sc_brtcnt--; free(n, M_DEVBUF); n = p; if (sc->sc_brtcnt <= sc->sc_brtmax) { splx(s); return; } } } 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_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 * hz); } /* * Delete routes to a specific interface member. */ void bridge_rtdelete(sc, ifp) struct bridge_softc *sc; struct ifnet *ifp; { int i, s; struct bridge_rtnode *n, *p; s = splhigh(); if (sc->sc_rts == NULL) { splx(s); return; } /* * 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); } } 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; u_int32_t cnt; struct bridge_rtnode *n; struct ifbareq bareq; s = splhigh(); if (sc->sc_rts == NULL) { baconf->ifbac_len = 0; splx(s); return (0); } if (baconf->ifbac_len == 0) { baconf->ifbac_len = sc->sc_brtcnt * sizeof(struct ifbareq); splx(s); return (0); } for (i = 0, cnt = 0; i < BRIDGE_RTABLE_SIZE; i++) { n = LIST_FIRST(&sc->sc_rts[i]); while (n != NULL) { if (baconf->ifbac_len < sizeof(struct ifbareq)) { baconf->ifbac_len = cnt * sizeof(struct ifbareq); splx(s); return (0); } bcopy(n->brt_if->if_xname, bareq.ifba_name, sizeof(bareq.ifba_name)); bcopy(&n->brt_addr, &bareq.ifba_dst, sizeof(bareq.ifba_dst)); bareq.ifba_age = n->brt_age; error = copyout((caddr_t)&bareq, (caddr_t)(baconf->ifbac_req + cnt), sizeof(bareq)); if (error) { baconf->ifbac_len = cnt * sizeof(struct ifbareq); splx(s); return (error); } n = LIST_NEXT(n, brt_next); cnt++; } } baconf->ifbac_len = cnt * sizeof(struct ifbareq); splx(s); return (0); } #if defined(INET) && (defined(IPFILTER) || defined(IPFILTER_LKM)) /* * 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 */ int bridge_filter(sc, ifp, eh, n) struct bridge_softc *sc; struct ifnet *ifp; struct ether_header *eh; struct mbuf *n; { struct mbuf *m, *m0; struct ip *ip; u_int16_t etype; int hlen, r; if (fr_checkp == NULL) return (BRIDGE_FILTER_PASS); /* * XXX TODO: Handle LSAP packets */ etype = ntohs(eh->ether_type); if (etype != ETHERTYPE_IP) return (BRIDGE_FILTER_PASS); /* * We need a full copy because we're going to be destructive * to the packet before we pass it to the ip filter code. * XXX This needs to be turned into a munge -> check -> * XXX unmunge section, for now, we copy. */ m = m_copym2(n, 0, M_COPYALL, M_NOWAIT); if (m == NULL) return (BRIDGE_FILTER_DROP); m->m_pkthdr.rcvif = &sc->sc_if; /* * Pull up the IP header */ if (m->m_len < sizeof(struct ip)) { m = m_pullup(m, sizeof(struct ip)); if (m == NULL) return (BRIDGE_FILTER_DROP); } /* * Examine the ip header, and drop invalid packets */ ip = mtod(m, struct ip *); if (ip->ip_v != IPVERSION) { r = BRIDGE_FILTER_DROP; goto out; } hlen = ip->ip_hl << 2; /* get whole header length */ if (hlen < sizeof(struct ip)) { r = BRIDGE_FILTER_DROP; goto out; } if (hlen > m->m_len) { /* pull up whole header */ if ((m = m_pullup(m, hlen)) == 0) { r = BRIDGE_FILTER_DROP; goto out; } ip = mtod(m, struct ip *); } if ((ip->ip_sum = in_cksum(m, hlen)) != 0) { r = BRIDGE_FILTER_DROP; goto out; } NTOHS(ip->ip_len); if (ip->ip_len < hlen) { r = BRIDGE_FILTER_DROP; goto out; } NTOHS(ip->ip_id); NTOHS(ip->ip_off); if (m->m_pkthdr.len < ip->ip_len) { r = BRIDGE_FILTER_DROP; goto out; } 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! */ m0 = m; if (fr_checkp && (*fr_checkp)(ip, hlen, m->m_pkthdr.rcvif, 0, &m0)) return (BRIDGE_FILTER_DROP); ip = mtod(m = m0, struct ip *); r = BRIDGE_FILTER_PASS; out: m_freem(m); return (r); } #endif #endif /* NBRIDGE */