/* $OpenBSD: ipx_input.c,v 1.21 2006/03/05 21:48:57 miod Exp $ */ /*- * * Copyright (c) 1996 Michael Shalayeff * Copyright (c) 1995, Mike Mitchell * Copyright (c) 1984, 1985, 1986, 1987, 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. 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. * * @(#)ipx_input.c * * from FreeBSD Id: ipx_input.c,v 1.8 1996/03/11 15:13:48 davidg Exp */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifndef IPXPRINTFS #define IPXPRINTFS 1 /* printing forwarding information */ #endif int ipxprintfs = IPXPRINTFS; int ipxcksum = 0; int ipxdonosocks = 0; int ipxforwarding = 0; int ipxnetbios = 0; union ipx_net ipx_zeronet; union ipx_host ipx_zerohost; union ipx_net ipx_broadnet; union ipx_host ipx_broadhost; struct ipxstat ipxstat; struct sockaddr_ipx ipx_netmask, ipx_hostmask; static u_int16_t allones[] = {0xffff, 0xffff, 0xffff}; #ifndef IPXCBHASHSIZE #define IPXCBHASHSIZE 32 #endif struct ipxpcbtable ipxrawcbtable; int ipxrawcbhashsize = IPXCBHASHSIZE; struct ipx_ifaddrhead ipx_ifaddr; struct ifqueue ipxintrq; int ipxqmaxlen = IFQ_MAXLEN; u_long ipx_pexseq; /* * IPX initialization. */ void ipx_init() { ipx_broadnet = * (union ipx_net *) allones; ipx_broadhost = * (union ipx_host *) allones; ipx_pexseq = arc4random(); ipxintrq.ifq_maxlen = ipxqmaxlen; ipx_netmask.sipx_len = 6; ipx_netmask.sipx_addr.ipx_net = ipx_broadnet; ipx_hostmask.sipx_len = 12; ipx_hostmask.sipx_addr.ipx_net = ipx_broadnet; ipx_hostmask.sipx_addr.ipx_host = ipx_broadhost; ipx_pcbinit(&ipxrawcbtable, ipxrawcbhashsize); TAILQ_INIT(&ipx_ifaddr); } /* * IPX input routine. Pass to next level. */ void ipxintr() { struct ipx *ipx; struct mbuf *m; struct ipxpcb *ipxp; struct ipx_ifaddr *ia; int len, s; next: /* * Get next datagram off input queue and get IPX header * in first mbuf. */ s = splnet(); IF_DEQUEUE(&ipxintrq, m); splx(s); if (m == NULL) { return; } ipxstat.ipxs_total++; if ((m->m_flags & M_EXT || m->m_len < sizeof(struct ipx)) && (m = m_pullup(m, sizeof(struct ipx))) == 0) { ipxstat.ipxs_toosmall++; goto next; } /* * Give any raw listeners a crack at the packet */ CIRCLEQ_FOREACH(ipxp, &ipxrawcbtable.input_queue, ipxp_queue) { struct mbuf *m1 = m_copy(m, 0, (int)M_COPYALL); if (m1) ipx_input(m1, ipxp); } ipx = mtod(m, struct ipx *); len = ntohs(ipx->ipx_len); /* * Check that the amount of data in the buffers * is as at least much as the IPX header would have us expect. * Trim mbufs if longer than we expect. * Drop packet if shorter than we expect. */ if (m->m_pkthdr.len < len) { ipxstat.ipxs_tooshort++; goto bad; } if (m->m_pkthdr.len > len) { if (m->m_len == m->m_pkthdr.len) { m->m_len = len; m->m_pkthdr.len = len; } else m_adj(m, len - m->m_pkthdr.len); } if (ipxcksum && ipx->ipx_sum != 0xffff) { if (ipx->ipx_sum != ipx_cksum(m, len)) { ipxstat.ipxs_badsum++; goto bad; } } /* * Propagated (Netbios) packets (type 20) has to be handled * different. :-( */ if (ipx->ipx_pt == IPXPROTO_NETBIOS) { if (ipxnetbios) { ipx_output_type20(m); goto next; } else goto bad; } /* * Is this a directed broadcast? */ if (ipx_hosteqnh(ipx_broadhost,ipx->ipx_dna.ipx_host)) { if ((!ipx_neteq(ipx->ipx_dna, ipx->ipx_sna)) && (!ipx_neteqnn(ipx->ipx_dna.ipx_net, ipx_broadnet)) && (!ipx_neteqnn(ipx->ipx_sna.ipx_net, ipx_zeronet)) && (!ipx_neteqnn(ipx->ipx_dna.ipx_net, ipx_zeronet)) ) { /* * If it is a broadcast to the net where it was * received from, treat it as ours. */ TAILQ_FOREACH(ia, &ipx->if_addr, ia_list) if((ia->ia_ifa.ifa_ifp == m->m_pkthdr.rcvif) && ipx_neteq(ia->ia_addr.sipx_addr, ipx->ipx_dna)) goto ours; /* * Look to see if I need to eat this packet. * Algorithm is to forward all young packets * and prematurely age any packets which will * by physically broadcasted. * Any very old packets eaten without forwarding * would die anyway. * * Suggestion of Bill Nesheim, Cornell U. */ if (ipx->ipx_tc < IPX_MAXHOPS) { ipx_forward(m); goto next; } } /* * Is this our packet? If not, forward. */ } else { TAILQ_FOREACH(ia, &ipx_ifaddr, ia_list) if (ipx_hosteq(ipx->ipx_dna, ia->ia_addr.sipx_addr) && (ipx_neteq(ipx->ipx_dna, ia->ia_addr.sipx_addr) || ipx_neteqnn(ipx->ipx_dna.ipx_net, ipx_zeronet))) break; if (ia == NULL) { ipx_forward(m); goto next; } } ours: /* * Locate pcb for datagram. */ ipxp = ipx_pcblookup(&ipx->ipx_sna, ipx->ipx_dna.ipx_port, IPX_WILDCARD); /* * Switch out to protocol's input routine. */ if (ipxp) { ipxstat.ipxs_delivered++; if ((ipxp->ipxp_flags & IPXP_ALL_PACKETS) == 0) switch (ipx->ipx_pt) { case IPXPROTO_SPX: spx_input(m, ipxp); goto next; } ipx_input(m, ipxp); } else goto bad; goto next; bad: m_freem(m); goto next; } void * ipx_ctlinput(cmd, arg_as_sa, dummy) int cmd; struct sockaddr *arg_as_sa; /* XXX should be swapped with dummy */ void *dummy; { caddr_t arg = (/* XXX */ caddr_t)arg_as_sa; struct ipx_addr *ipx; if (cmd < 0 || cmd >= PRC_NCMDS) return NULL; switch (cmd) { struct sockaddr_ipx *sipx; case PRC_IFDOWN: case PRC_HOSTDEAD: case PRC_HOSTUNREACH: sipx = (struct sockaddr_ipx *)arg; if (sipx == NULL || sipx->sipx_family != AF_IPX) return NULL; ipx = &sipx->sipx_addr; break; default: break; } return NULL; } /* * Forward a packet. If some error occurs return the sender * an error packet. Note we can't always generate a meaningful * error message because the IPX errors don't have a large enough repetoire * of codes and types. */ struct route ipx_droute; struct route ipx_sroute; void ipx_forward(m) struct mbuf *m; { struct ipx *ipx = mtod(m, struct ipx *); int error; int agedelta = 1; int flags = IPX_FORWARDING; int ok_there = 0; int ok_back = 0; if (ipxforwarding == 0) { ipxstat.ipxs_cantforward++; m_freem(m); goto cleanup; } ipx->ipx_tc++; if (ipx->ipx_tc > IPX_MAXHOPS) { ipxstat.ipxs_cantforward++; m_freem(m); goto cleanup; } if ((ok_there = ipx_do_route(&ipx->ipx_dna,&ipx_droute)) == 0) { ipxstat.ipxs_noroute++; m_freem(m); goto cleanup; } /* * Here we think about forwarding broadcast packets, * so we try to insure that it doesn't go back out * on the interface it came in on. Also, if we * are going to physically broadcast this, let us * age the packet so we can eat it safely the second time around. */ if (ipx->ipx_dna.ipx_host.c_host[0] & 0x1) { struct ipx_ifaddr *ia = ipx_iaonnetof(&ipx->ipx_dna); struct ifnet *ifp; if (ia) { /* I'm gonna hafta eat this packet */ agedelta += IPX_MAXHOPS - ipx->ipx_tc; ipx->ipx_tc = IPX_MAXHOPS; } if ((ok_back = ipx_do_route(&ipx->ipx_sna,&ipx_sroute)) == 0) { /* error = ENETUNREACH; He'll never get it! */ ipxstat.ipxs_noroute++; m_freem(m); goto cleanup; } if (ipx_droute.ro_rt && (ifp=ipx_droute.ro_rt->rt_ifp) && ipx_sroute.ro_rt && (ifp!=ipx_sroute.ro_rt->rt_ifp)) { flags |= IPX_ALLOWBROADCAST; } else { ipxstat.ipxs_noroute++; m_freem(m); goto cleanup; } } /* * We don't need to recompute checksum because ipx_tc field * is ignored by checksum calculation routine, however * it may be desirable to reset checksum if ipxcksum == 0 */ #if 0 if (!ipxcksum) ipx->ipx_sum = 0xffff; #endif error = ipx_outputfl(m, &ipx_droute, flags); if (error == 0) { ipxstat.ipxs_forward++; if (ipxprintfs) { printf("forward: "); ipx_printhost(&ipx->ipx_sna); printf(" to "); ipx_printhost(&ipx->ipx_dna); printf(" hops %d\n", ipx->ipx_tc); } } else { switch (error) { case ENETUNREACH: case EHOSTDOWN: case EHOSTUNREACH: case ENETDOWN: case EPERM: ipxstat.ipxs_noroute++; break; case EMSGSIZE: ipxstat.ipxs_mtutoosmall++; break; case ENOBUFS: ipxstat.ipxs_odropped++; break; } m_freem(m); } cleanup: if (ok_there) ipx_undo_route(&ipx_droute); if (ok_back) ipx_undo_route(&ipx_sroute); } int ipx_do_route(src, ro) struct ipx_addr *src; struct route *ro; { struct sockaddr_ipx *dst; bzero((caddr_t)ro, sizeof(*ro)); dst = (struct sockaddr_ipx *)&ro->ro_dst; dst->sipx_len = sizeof(*dst); dst->sipx_family = AF_IPX; dst->sipx_addr = *src; dst->sipx_addr.ipx_port = 0; rtalloc(ro); if (ro->ro_rt == 0 || ro->ro_rt->rt_ifp == 0) { return (0); } ro->ro_rt->rt_use++; return (1); } void ipx_undo_route(ro) register struct route *ro; { if (ro->ro_rt) { RTFREE(ro->ro_rt); } } void ipx_watch_output(m, ifp) struct mbuf *m; struct ifnet *ifp; { struct ipxpcb *ipxp; struct ifaddr *ifa; struct ipx_ifaddr *ia; /* * Give any raw listeners a crack at the packet */ CIRCLEQ_FOREACH(ipxp, &ipxrawcbtable.ipxpt_queue, ipxp_queue) { struct mbuf *m0 = m_copy(m, 0, (int)M_COPYALL); if (m0) { struct ipx *ipx; M_PREPEND(m0, sizeof(*ipx), M_DONTWAIT); if (m0 == NULL) continue; ipx = mtod(m0, struct ipx *); ipx->ipx_sna.ipx_net = ipx_zeronet; TAILQ_FOREACH(ia, &ipx_ifaddr, ia_list) if (ifp == ia->ia_ifp) break; if (ia == NULL) ipx->ipx_sna.ipx_host = ipx_zerohost; else ipx->ipx_sna.ipx_host = ia->ia_addr.sipx_addr.ipx_host; if (ifp && (ifp->if_flags & IFF_POINTOPOINT)) TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { if (ifa->ifa_addr->sa_family == AF_IPX) { ipx->ipx_sna = IA_SIPX(ifa)->sipx_addr; break; } } ipx->ipx_len = ntohl(m0->m_pkthdr.len); ipx_input(m0, ipxp); } } }