/* * Copyright (c) 1983, 1988, 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. 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. */ #ifndef lint /*static char sccsid[] = "from: @(#)startup.c 8.1 (Berkeley) 6/5/93";*/ static char *rcsid = "$Id: startup.c,v 1.7 1994/09/23 14:28:09 mycroft Exp $"; #endif /* not lint */ /* * Routing Table Management Daemon */ #include "defs.h" #include #include #include #include #include #include #include "pathnames.h" struct interface *ifnet; struct interface **ifnext = &ifnet; int lookforinterfaces = 1; int externalinterfaces = 0; /* # of remote and local interfaces */ int foundloopback; /* valid flag for loopaddr */ struct sockaddr loopaddr; /* our address on loopback */ void quit(s) char *s; { extern int errno; int sverrno = errno; (void) fprintf(stderr, "route: "); if (s) (void) fprintf(stderr, "%s: ", s); (void) fprintf(stderr, "%s\n", strerror(sverrno)); exit(1); /* NOTREACHED */ } struct rt_addrinfo info; /* Sleazy use of local variables throughout file, warning!!!! */ #define netmask info.rti_info[RTAX_NETMASK] #define ifaaddr info.rti_info[RTAX_IFA] #define brdaddr info.rti_info[RTAX_BRD] #define ROUNDUP(a) \ ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long)) #define ADVANCE(x, n) (x += ROUNDUP((n)->sa_len)) void rt_xaddrs(cp, cplim, rtinfo) register caddr_t cp, cplim; register struct rt_addrinfo *rtinfo; { register struct sockaddr *sa; register int i; memset(rtinfo->rti_info, 0, sizeof(rtinfo->rti_info)); for (i = 0; (i < RTAX_MAX) && (cp < cplim); i++) { if ((rtinfo->rti_addrs & (1 << i)) == 0) continue; rtinfo->rti_info[i] = sa = (struct sockaddr *)cp; ADVANCE(cp, sa); } } /* * Find the network interfaces which have configured themselves. * If the interface is present but not yet up (for example an * ARPANET IMP), set the lookforinterfaces flag so we'll * come back later and look again. */ ifinit() { struct interface ifs, *ifp; size_t needed; int mib[6], no_ipaddr = 0, flags = 0; char *buf, *cplim, *cp; register struct if_msghdr *ifm; register struct ifa_msghdr *ifam; struct sockaddr_dl *sdl; struct sockaddr_in *sin; u_long i; mib[0] = CTL_NET; mib[1] = PF_ROUTE; mib[2] = 0; mib[3] = AF_INET; mib[4] = NET_RT_IFLIST; mib[5] = 0; if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) quit("route-sysctl-estimate"); if ((buf = malloc(needed)) == NULL) quit("malloc"); if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) quit("actual retrieval of interface table"); lookforinterfaces = 0; cplim = buf + needed; for (cp = buf; cp < cplim; cp += ifm->ifm_msglen) { ifm = (struct if_msghdr *)cp; if (ifm->ifm_type == RTM_IFINFO) { memset(&ifs, 0, sizeof(ifs)); ifs.int_flags = flags = (0xffff & ifm->ifm_flags) | IFF_INTERFACE; if ((flags & IFF_UP) == 0 || no_ipaddr) lookforinterfaces = 1; sdl = (struct sockaddr_dl *) (ifm + 1); sdl->sdl_data[sdl->sdl_nlen] = 0; no_ipaddr = 1; continue; } if (ifm->ifm_type != RTM_NEWADDR) quit("ifinit: out of sync"); if ((flags & IFF_UP) == 0) continue; ifam = (struct ifa_msghdr *)ifm; info.rti_addrs = ifam->ifam_addrs; rt_xaddrs((char *)(ifam + 1), cp + ifam->ifam_msglen, &info); if (ifaaddr == 0) { syslog(LOG_ERR, "%s: (get addr)", sdl->sdl_data); continue; } ifs.int_addr = *ifaaddr; if (ifs.int_addr.sa_family != AF_INET) continue; no_ipaddr = 0; if (ifs.int_flags & IFF_POINTOPOINT) { if (brdaddr == 0) { syslog(LOG_ERR, "%s: (get dstaddr)", sdl->sdl_data); continue; } if (brdaddr->sa_family == AF_UNSPEC) { lookforinterfaces = 1; continue; } ifs.int_dstaddr = *brdaddr; } /* * already known to us? * This allows multiple point-to-point links * to share a source address (possibly with one * other link), but assumes that there will not be * multiple links with the same destination address. */ if (ifs.int_flags & IFF_POINTOPOINT) { if (if_ifwithdstaddr(&ifs.int_dstaddr)) continue; } else if (if_ifwithaddr(&ifs.int_addr)) continue; if (ifs.int_flags & IFF_LOOPBACK) { ifs.int_flags |= IFF_PASSIVE; foundloopback = 1; loopaddr = ifs.int_addr; for (ifp = ifnet; ifp; ifp = ifp->int_next) if (ifp->int_flags & IFF_POINTOPOINT) add_ptopt_localrt(ifp); } if (ifs.int_flags & IFF_BROADCAST) { if (brdaddr == 0) { syslog(LOG_ERR, "%s: (get broadaddr)", sdl->sdl_data); continue; } ifs.int_dstaddr = *brdaddr; } /* * Use a minimum metric of one; * treat the interface metric (default 0) * as an increment to the hop count of one. */ ifs.int_metric = ifam->ifam_metric + 1; if (netmask == 0) { syslog(LOG_ERR, "%s: (get netmask)", sdl->sdl_data); continue; } sin = (struct sockaddr_in *)netmask; ifs.int_subnetmask = ntohl(sin->sin_addr.s_addr); sin = (struct sockaddr_in *)&ifs.int_addr; i = ntohl(sin->sin_addr.s_addr); if (IN_CLASSA(i)) ifs.int_netmask = IN_CLASSA_NET; else if (IN_CLASSB(i)) ifs.int_netmask = IN_CLASSB_NET; else ifs.int_netmask = IN_CLASSC_NET; ifs.int_net = i & ifs.int_netmask; ifs.int_subnet = i & ifs.int_subnetmask; if (ifs.int_subnetmask != ifs.int_netmask) ifs.int_flags |= IFF_SUBNET; ifp = (struct interface *) malloc(sdl->sdl_nlen + 1 + sizeof(ifs)); if (ifp == 0) { printf("routed: out of memory\n"); lookforinterfaces = 1; break; } *ifp = ifs; /* * Count the # of directly connected networks * and point to point links which aren't looped * back to ourself. This is used below to * decide if we should be a routing ``supplier''. */ if ((ifs.int_flags & IFF_LOOPBACK) == 0 && ((ifs.int_flags & IFF_POINTOPOINT) == 0 || if_ifwithaddr(&ifs.int_dstaddr) == 0)) externalinterfaces++; /* * If we have a point-to-point link, we want to act * as a supplier even if it's our only interface, * as that's the only way our peer on the other end * can tell that the link is up. */ if ((ifs.int_flags & IFF_POINTOPOINT) && supplier < 0) supplier = 1; ifp->int_name = (char *)(ifp + 1); strcpy(ifp->int_name, sdl->sdl_data); *ifnext = ifp; ifnext = &ifp->int_next; traceinit(ifp); addrouteforif(ifp); } if (externalinterfaces > 1 && supplier < 0) supplier = 1; free(buf); } /* * Add route for interface if not currently installed. * Create route to other end if a point-to-point link, * otherwise a route to this (sub)network. * INTERNET SPECIFIC. */ addrouteforif(ifp) register struct interface *ifp; { struct sockaddr_in net; struct sockaddr *dst; int state; register struct rt_entry *rt; if (ifp->int_flags & IFF_POINTOPOINT) dst = &ifp->int_dstaddr; else { memset(&net, 0, sizeof (net)); net.sin_family = AF_INET; net.sin_addr = inet_makeaddr(ifp->int_subnet, INADDR_ANY); dst = (struct sockaddr *)&net; } rt = rtfind(dst); if (rt && (rt->rt_state & (RTS_INTERFACE | RTS_INTERNAL)) == RTS_INTERFACE) return; if (rt) rtdelete(rt); /* * If interface on subnetted network, * install route to network as well. * This is meant for external viewers. */ if ((ifp->int_flags & (IFF_SUBNET|IFF_POINTOPOINT)) == IFF_SUBNET) { struct in_addr subnet; subnet = net.sin_addr; net.sin_addr = inet_makeaddr(ifp->int_net, INADDR_ANY); rt = rtfind(dst); if (rt == 0) rtadd(dst, &ifp->int_addr, ifp->int_metric, ((ifp->int_flags & (IFF_INTERFACE|IFF_REMOTE)) | RTS_PASSIVE | RTS_INTERNAL | RTS_SUBNET)); else if ((rt->rt_state & (RTS_INTERNAL|RTS_SUBNET)) == (RTS_INTERNAL|RTS_SUBNET) && ifp->int_metric < rt->rt_metric) rtchange(rt, &rt->rt_router, ifp->int_metric); net.sin_addr = subnet; } if (ifp->int_transitions++ > 0) syslog(LOG_ERR, "re-installing interface %s", ifp->int_name); state = ifp->int_flags & (IFF_INTERFACE | IFF_PASSIVE | IFF_REMOTE | IFF_SUBNET); if (ifp->int_flags & IFF_POINTOPOINT && (ntohl(((struct sockaddr_in *)&ifp->int_dstaddr)->sin_addr.s_addr) & ifp->int_netmask) != ifp->int_net) state &= ~RTS_SUBNET; if (ifp->int_flags & IFF_LOOPBACK) state |= RTS_EXTERNAL; rtadd(dst, &ifp->int_addr, ifp->int_metric, state); if (ifp->int_flags & IFF_POINTOPOINT && foundloopback) add_ptopt_localrt(ifp); } /* * Add route to local end of point-to-point using loopback. * If a route to this network is being sent to neighbors on other nets, * mark this route as subnet so we don't have to propagate it too. */ add_ptopt_localrt(ifp) register struct interface *ifp; { struct rt_entry *rt; struct sockaddr *dst; struct sockaddr_in net; int state; state = RTS_INTERFACE | RTS_PASSIVE; /* look for route to logical network */ memset(&net, 0, sizeof (net)); net.sin_family = AF_INET; net.sin_addr = inet_makeaddr(ifp->int_net, INADDR_ANY); dst = (struct sockaddr *)&net; rt = rtfind(dst); if (rt && rt->rt_state & RTS_INTERNAL) state |= RTS_SUBNET; dst = &ifp->int_addr; if (rt = rtfind(dst)) { if (rt && rt->rt_state & RTS_INTERFACE) return; rtdelete(rt); } rtadd(dst, &loopaddr, 1, state); } /* * As a concession to the ARPANET we read a list of gateways * from /etc/gateways and add them to our tables. This file * exists at each ARPANET gateway and indicates a set of ``remote'' * gateways (i.e. a gateway which we can't immediately determine * if it's present or not as we can do for those directly connected * at the hardware level). If a gateway is marked ``passive'' * in the file, then we assume it doesn't have a routing process * of our design and simply assume it's always present. Those * not marked passive are treated as if they were directly * connected -- they're added into the interface list so we'll * send them routing updates. * * PASSIVE ENTRIES AREN'T NEEDED OR USED ON GATEWAYS RUNNING EGP. */ gwkludge() { struct sockaddr_in dst, gate; FILE *fp; char *type, *dname, *gname, *qual, buf[BUFSIZ]; struct interface *ifp; int metric, n; struct rt_entry route; fp = fopen(_PATH_GATEWAYS, "r"); if (fp == NULL) return; qual = buf; dname = buf + 64; gname = buf + ((BUFSIZ - 64) / 3); type = buf + (((BUFSIZ - 64) * 2) / 3); memset(&dst, 0, sizeof (dst)); memset(&gate, 0, sizeof (gate)); memset(&route, 0, sizeof(route)); /* format: {net | host} XX gateway XX metric DD [passive | external]\n */ #define readentry(fp) \ fscanf((fp), "%s %s gateway %s metric %d %s\n", \ type, dname, gname, &metric, qual) for (;;) { if ((n = readentry(fp)) == EOF) break; if (!getnetorhostname(type, dname, &dst)) continue; if (!gethostnameornumber(gname, &gate)) continue; if (metric == 0) /* XXX */ metric = 1; if (strcmp(qual, "passive") == 0) { /* * Passive entries aren't placed in our tables, * only the kernel's, so we don't copy all of the * external routing information within a net. * Internal machines should use the default * route to a suitable gateway (like us). */ route.rt_dst = *(struct sockaddr *) &dst; route.rt_router = *(struct sockaddr *) &gate; route.rt_flags = RTF_UP; if (strcmp(type, "host") == 0) route.rt_flags |= RTF_HOST; if (metric) route.rt_flags |= RTF_GATEWAY; (void) rtioctl(ADD, &route.rt_rt); continue; } if (strcmp(qual, "external") == 0) { /* * Entries marked external are handled * by other means, e.g. EGP, * and are placed in our tables only * to prevent overriding them * with something else. */ rtadd(&dst, &gate, metric, RTS_EXTERNAL|RTS_PASSIVE); continue; } /* assume no duplicate entries */ externalinterfaces++; ifp = (struct interface *)malloc(sizeof (*ifp)); memset(ifp, 0, sizeof (*ifp)); ifp->int_flags = IFF_REMOTE; /* can't identify broadcast capability */ ifp->int_net = inet_netof(dst.sin_addr); if (strcmp(type, "host") == 0) { ifp->int_flags |= IFF_POINTOPOINT; ifp->int_dstaddr = *((struct sockaddr *)&dst); } ifp->int_addr = *((struct sockaddr *)&gate); ifp->int_metric = metric; ifp->int_next = ifnet; ifnet = ifp; addrouteforif(ifp); } fclose(fp); } getnetorhostname(type, name, sin) char *type, *name; struct sockaddr_in *sin; { if (strcmp(type, "net") == 0) { struct netent *np = getnetbyname(name); int n; if (np == 0) n = inet_network(name); else { if (np->n_addrtype != AF_INET) return (0); n = np->n_net; /* * getnetbyname returns right-adjusted value. */ if (n < 128) n <<= IN_CLASSA_NSHIFT; else if (n < 65536) n <<= IN_CLASSB_NSHIFT; else n <<= IN_CLASSC_NSHIFT; } sin->sin_family = AF_INET; sin->sin_addr = inet_makeaddr(n, INADDR_ANY); return (1); } if (strcmp(type, "host") == 0) { struct hostent *hp = gethostbyname(name); if (hp == 0) sin->sin_addr.s_addr = inet_addr(name); else { if (hp->h_addrtype != AF_INET) return (0); memcpy(&sin->sin_addr, hp->h_addr, hp->h_length); } sin->sin_family = AF_INET; return (1); } return (0); } gethostnameornumber(name, sin) char *name; struct sockaddr_in *sin; { struct hostent *hp; hp = gethostbyname(name); if (hp) { memcpy(&sin->sin_addr, hp->h_addr, hp->h_length); sin->sin_family = hp->h_addrtype; return (1); } sin->sin_addr.s_addr = inet_addr(name); sin->sin_family = AF_INET; return (sin->sin_addr.s_addr != -1); }