/* * Copyright (c) 1982, 1986, 1991, 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. * * @(#)in.c 8.4 (Berkeley) 1/9/95 * $Id: in.c,v 1.26 1996/12/13 21:28:52 wollman Exp $ */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * This structure is used to keep track of in_multi chains which belong to * deleted interface addresses. */ static LIST_HEAD(, multi_kludge) in_mk; /* XXX BSS initialization */ struct multi_kludge { LIST_ENTRY(multi_kludge) mk_entry; struct ifnet *mk_ifp; struct in_multihead mk_head; }; static void in_socktrim __P((struct sockaddr_in *)); static int in_ifinit __P((struct ifnet *, struct in_ifaddr *, struct sockaddr_in *, int)); static void in_ifscrub __P((struct ifnet *, struct in_ifaddr *)); static int subnetsarelocal = 0; SYSCTL_INT(_net_inet_ip, OID_AUTO, subnets_are_local, CTLFLAG_RW, &subnetsarelocal, 0, ""); /* * Return 1 if an internet address is for a ``local'' host * (one to which we have a connection). If subnetsarelocal * is true, this includes other subnets of the local net. * Otherwise, it includes only the directly-connected (sub)nets. */ int in_localaddr(in) struct in_addr in; { register u_long i = ntohl(in.s_addr); register struct in_ifaddr *ia; if (subnetsarelocal) { for (ia = in_ifaddrhead.tqh_first; ia; ia = ia->ia_link.tqe_next) if ((i & ia->ia_netmask) == ia->ia_net) return (1); } else { for (ia = in_ifaddrhead.tqh_first; ia; ia = ia->ia_link.tqe_next) if ((i & ia->ia_subnetmask) == ia->ia_subnet) return (1); } return (0); } /* * Determine whether an IP address is in a reserved set of addresses * that may not be forwarded, or whether datagrams to that destination * may be forwarded. */ int in_canforward(in) struct in_addr in; { register u_long i = ntohl(in.s_addr); register u_long net; if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i)) return (0); if (IN_CLASSA(i)) { net = i & IN_CLASSA_NET; if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT)) return (0); } return (1); } /* * Trim a mask in a sockaddr */ static void in_socktrim(ap) struct sockaddr_in *ap; { register char *cplim = (char *) &ap->sin_addr; register char *cp = (char *) (&ap->sin_addr + 1); ap->sin_len = 0; while (--cp >= cplim) if (*cp) { (ap)->sin_len = cp - (char *) (ap) + 1; break; } } static int in_interfaces; /* number of external internet interfaces */ /* * Generic internet control operations (ioctl's). * Ifp is 0 if not an interface-specific ioctl. */ /* ARGSUSED */ int in_control(so, cmd, data, ifp) struct socket *so; u_long cmd; caddr_t data; register struct ifnet *ifp; { register struct ifreq *ifr = (struct ifreq *)data; register struct in_ifaddr *ia = 0, *iap; register struct ifaddr *ifa; struct in_ifaddr *oia; struct in_aliasreq *ifra = (struct in_aliasreq *)data; struct sockaddr_in oldaddr; int error, hostIsNew, maskIsNew, s; u_long i; struct multi_kludge *mk; /* * Find address for this interface, if it exists. * * If an alias address was specified, find that one instead of * the first one on the interface. */ if (ifp) for (iap = in_ifaddrhead.tqh_first; iap; iap = iap->ia_link.tqe_next) if (iap->ia_ifp == ifp) { if (((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr.s_addr == iap->ia_addr.sin_addr.s_addr) { ia = iap; break; } else if (ia == NULL) { ia = iap; if (ifr->ifr_addr.sa_family != AF_INET) break; } } switch (cmd) { case SIOCAIFADDR: case SIOCDIFADDR: if (ifra->ifra_addr.sin_family == AF_INET) { for (oia = ia; ia; ia = ia->ia_link.tqe_next) { if (ia->ia_ifp == ifp && ia->ia_addr.sin_addr.s_addr == ifra->ifra_addr.sin_addr.s_addr) break; } if ((ifp->if_flags & IFF_POINTOPOINT) && (cmd == SIOCAIFADDR) && (ifra->ifra_dstaddr.sin_addr.s_addr == INADDR_ANY)) { return EDESTADDRREQ; } } if (cmd == SIOCDIFADDR && ia == 0) return (EADDRNOTAVAIL); /* FALLTHROUGH */ case SIOCSIFADDR: case SIOCSIFNETMASK: case SIOCSIFDSTADDR: if ((so->so_state & SS_PRIV) == 0) return (EPERM); if (ifp == 0) panic("in_control"); if (ia == (struct in_ifaddr *)0) { ia = (struct in_ifaddr *) malloc(sizeof *ia, M_IFADDR, M_WAITOK); if (ia == (struct in_ifaddr *)NULL) return (ENOBUFS); bzero((caddr_t)ia, sizeof *ia); /* * Protect from ipintr() traversing address list * while we're modifying it. */ s = splnet(); TAILQ_INSERT_TAIL(&in_ifaddrhead, ia, ia_link); ifa = &ia->ia_ifa; TAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link); ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr; ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr; ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask; ia->ia_sockmask.sin_len = 8; if (ifp->if_flags & IFF_BROADCAST) { ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr); ia->ia_broadaddr.sin_family = AF_INET; } ia->ia_ifp = ifp; if (!(ifp->if_flags & IFF_LOOPBACK)) in_interfaces++; splx(s); } break; case SIOCSIFBRDADDR: if ((so->so_state & SS_PRIV) == 0) return (EPERM); /* FALLTHROUGH */ case SIOCGIFADDR: case SIOCGIFNETMASK: case SIOCGIFDSTADDR: case SIOCGIFBRDADDR: if (ia == (struct in_ifaddr *)0) return (EADDRNOTAVAIL); break; } switch (cmd) { case SIOCGIFADDR: *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr; break; case SIOCGIFBRDADDR: if ((ifp->if_flags & IFF_BROADCAST) == 0) return (EINVAL); *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr; break; case SIOCGIFDSTADDR: if ((ifp->if_flags & IFF_POINTOPOINT) == 0) return (EINVAL); *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr; break; case SIOCGIFNETMASK: *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask; break; case SIOCSIFDSTADDR: if ((ifp->if_flags & IFF_POINTOPOINT) == 0) return (EINVAL); oldaddr = ia->ia_dstaddr; ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr; if (ifp->if_ioctl && (error = (*ifp->if_ioctl) (ifp, SIOCSIFDSTADDR, (caddr_t)ia))) { ia->ia_dstaddr = oldaddr; return (error); } if (ia->ia_flags & IFA_ROUTE) { ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr; rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST); ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr; rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP); } break; case SIOCSIFBRDADDR: if ((ifp->if_flags & IFF_BROADCAST) == 0) return (EINVAL); ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr; break; case SIOCSIFADDR: return (in_ifinit(ifp, ia, (struct sockaddr_in *) &ifr->ifr_addr, 1)); case SIOCSIFNETMASK: i = ifra->ifra_addr.sin_addr.s_addr; ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr = i); break; case SIOCAIFADDR: maskIsNew = 0; hostIsNew = 1; error = 0; if (ia->ia_addr.sin_family == AF_INET) { if (ifra->ifra_addr.sin_len == 0) { ifra->ifra_addr = ia->ia_addr; hostIsNew = 0; } else if (ifra->ifra_addr.sin_addr.s_addr == ia->ia_addr.sin_addr.s_addr) hostIsNew = 0; } if (ifra->ifra_mask.sin_len) { in_ifscrub(ifp, ia); ia->ia_sockmask = ifra->ifra_mask; ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr); maskIsNew = 1; } if ((ifp->if_flags & IFF_POINTOPOINT) && (ifra->ifra_dstaddr.sin_family == AF_INET)) { in_ifscrub(ifp, ia); ia->ia_dstaddr = ifra->ifra_dstaddr; maskIsNew = 1; /* We lie; but the effect's the same */ } if (ifra->ifra_addr.sin_family == AF_INET && (hostIsNew || maskIsNew)) error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0); if ((ifp->if_flags & IFF_BROADCAST) && (ifra->ifra_broadaddr.sin_family == AF_INET)) ia->ia_broadaddr = ifra->ifra_broadaddr; return (error); case SIOCDIFADDR: mk = malloc(sizeof *mk, M_IPMADDR, M_WAITOK); if (!mk) return ENOBUFS; in_ifscrub(ifp, ia); /* * Protect from ipintr() traversing address list * while we're modifying it. */ s = splnet(); ifa = &ia->ia_ifa; TAILQ_REMOVE(&ifp->if_addrhead, ifa, ifa_link); oia = ia; TAILQ_REMOVE(&in_ifaddrhead, oia, ia_link); if (!oia->ia_multiaddrs.lh_first) { IFAFREE(&oia->ia_ifa); FREE(mk, M_IPMADDR); splx(s); break; } /* * Multicast address kludge: * If there were any multicast addresses attached to this * interface address, either move them to another address * on this interface, or save them until such time as this * interface is reconfigured for IP. */ IFP_TO_IA(oia->ia_ifp, ia); if (ia) { /* there is another address */ struct in_multi *inm; for(inm = oia->ia_multiaddrs.lh_first; inm; inm = inm->inm_entry.le_next) { IFAFREE(&inm->inm_ia->ia_ifa); ia->ia_ifa.ifa_refcnt++; inm->inm_ia = ia; LIST_INSERT_HEAD(&ia->ia_multiaddrs, inm, inm_entry); } FREE(mk, M_IPMADDR); } else { /* last address on this if deleted, save */ struct in_multi *inm; LIST_INIT(&mk->mk_head); mk->mk_ifp = ifp; for(inm = oia->ia_multiaddrs.lh_first; inm; inm = inm->inm_entry.le_next) { LIST_INSERT_HEAD(&mk->mk_head, inm, inm_entry); } if (mk->mk_head.lh_first) { LIST_INSERT_HEAD(&in_mk, mk, mk_entry); } else { FREE(mk, M_IPMADDR); } } IFAFREE((&oia->ia_ifa)); splx(s); break; default: if (ifp == 0 || ifp->if_ioctl == 0) return (EOPNOTSUPP); return ((*ifp->if_ioctl)(ifp, cmd, data)); } return (0); } /* * Delete any existing route for an interface. */ static void in_ifscrub(ifp, ia) register struct ifnet *ifp; register struct in_ifaddr *ia; { if ((ia->ia_flags & IFA_ROUTE) == 0) return; if (ifp->if_flags & (IFF_LOOPBACK|IFF_POINTOPOINT)) rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST); else rtinit(&(ia->ia_ifa), (int)RTM_DELETE, 0); ia->ia_flags &= ~IFA_ROUTE; } /* * Initialize an interface's internet address * and routing table entry. */ static int in_ifinit(ifp, ia, sin, scrub) register struct ifnet *ifp; register struct in_ifaddr *ia; struct sockaddr_in *sin; int scrub; { register u_long i = ntohl(sin->sin_addr.s_addr); struct sockaddr_in oldaddr; int s = splimp(), flags = RTF_UP, error; struct multi_kludge *mk; oldaddr = ia->ia_addr; ia->ia_addr = *sin; /* * Give the interface a chance to initialize * if this is its first address, * and to validate the address if necessary. */ if (ifp->if_ioctl && (error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia))) { splx(s); ia->ia_addr = oldaddr; return (error); } splx(s); if (scrub) { ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr; in_ifscrub(ifp, ia); ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr; } if (IN_CLASSA(i)) ia->ia_netmask = IN_CLASSA_NET; else if (IN_CLASSB(i)) ia->ia_netmask = IN_CLASSB_NET; else ia->ia_netmask = IN_CLASSC_NET; /* * The subnet mask usually includes at least the standard network part, * but may may be smaller in the case of supernetting. * If it is set, we believe it. */ if (ia->ia_subnetmask == 0) { ia->ia_subnetmask = ia->ia_netmask; ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask); } else ia->ia_netmask &= ia->ia_subnetmask; ia->ia_net = i & ia->ia_netmask; ia->ia_subnet = i & ia->ia_subnetmask; in_socktrim(&ia->ia_sockmask); /* * Add route for the network. */ ia->ia_ifa.ifa_metric = ifp->if_metric; if (ifp->if_flags & IFF_BROADCAST) { ia->ia_broadaddr.sin_addr.s_addr = htonl(ia->ia_subnet | ~ia->ia_subnetmask); ia->ia_netbroadcast.s_addr = htonl(ia->ia_net | ~ ia->ia_netmask); } else if (ifp->if_flags & IFF_LOOPBACK) { ia->ia_ifa.ifa_dstaddr = ia->ia_ifa.ifa_addr; flags |= RTF_HOST; } else if (ifp->if_flags & IFF_POINTOPOINT) { if (ia->ia_dstaddr.sin_family != AF_INET) return (0); flags |= RTF_HOST; } if ((error = rtinit(&(ia->ia_ifa), (int)RTM_ADD, flags)) == 0) ia->ia_flags |= IFA_ROUTE; LIST_INIT(&ia->ia_multiaddrs); /* * If the interface supports multicast, join the "all hosts" * multicast group on that interface. */ if (ifp->if_flags & IFF_MULTICAST) { struct in_addr addr; /* * Continuation of multicast address hack: * If there was a multicast group list previously saved * for this interface, then we re-attach it to the first * address configured on the i/f. */ for(mk = in_mk.lh_first; mk; mk = mk->mk_entry.le_next) { if(mk->mk_ifp == ifp) { struct in_multi *inm; for(inm = mk->mk_head.lh_first; inm; inm = inm->inm_entry.le_next) { IFAFREE(&inm->inm_ia->ia_ifa); ia->ia_ifa.ifa_refcnt++; inm->inm_ia = ia; LIST_INSERT_HEAD(&ia->ia_multiaddrs, inm, inm_entry); } LIST_REMOVE(mk, mk_entry); free(mk, M_IPMADDR); break; } } addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP); in_addmulti(&addr, ifp); } return (error); } /* * Return 1 if the address might be a local broadcast address. */ int in_broadcast(in, ifp) struct in_addr in; struct ifnet *ifp; { register struct ifaddr *ifa; u_long t; if (in.s_addr == INADDR_BROADCAST || in.s_addr == INADDR_ANY) return 1; if ((ifp->if_flags & IFF_BROADCAST) == 0) return 0; t = ntohl(in.s_addr); /* * Look through the list of addresses for a match * with a broadcast address. */ #define ia ((struct in_ifaddr *)ifa) for (ifa = ifp->if_addrhead.tqh_first; ifa; ifa = ifa->ifa_link.tqe_next) if (ifa->ifa_addr->sa_family == AF_INET && (in.s_addr == ia->ia_broadaddr.sin_addr.s_addr || in.s_addr == ia->ia_netbroadcast.s_addr || /* * Check for old-style (host 0) broadcast. */ t == ia->ia_subnet || t == ia->ia_net) && /* * Check for an all one subnetmask. These * only exist when an interface gets a secondary * address. */ ia->ia_subnetmask != (u_long)0xffffffff) return 1; return (0); #undef ia } /* * Add an address to the list of IP multicast addresses for a given interface. */ struct in_multi * in_addmulti(ap, ifp) register struct in_addr *ap; register struct ifnet *ifp; { register struct in_multi *inm; struct ifreq ifr; struct in_ifaddr *ia; int s = splnet(); /* * See if address already in list. */ IN_LOOKUP_MULTI(*ap, ifp, inm); if (inm != NULL) { /* * Found it; just increment the reference count. */ ++inm->inm_refcount; } else { /* * New address; allocate a new multicast record * and link it into the interface's multicast list. */ inm = (struct in_multi *)malloc(sizeof(*inm), M_IPMADDR, M_NOWAIT); if (inm == NULL) { splx(s); return (NULL); } inm->inm_addr = *ap; inm->inm_ifp = ifp; inm->inm_refcount = 1; IFP_TO_IA(ifp, ia); if (ia == NULL) { free(inm, M_IPMADDR); splx(s); return (NULL); } inm->inm_ia = ia; ia->ia_ifa.ifa_refcnt++; /* gain a reference */ LIST_INSERT_HEAD(&ia->ia_multiaddrs, inm, inm_entry); /* * Ask the network driver to update its multicast reception * filter appropriately for the new address. */ ((struct sockaddr_in *)&ifr.ifr_addr)->sin_family = AF_INET; ((struct sockaddr_in *)&ifr.ifr_addr)->sin_addr = *ap; if ((ifp->if_ioctl == NULL) || (*ifp->if_ioctl)(ifp, SIOCADDMULTI,(caddr_t)&ifr) != 0) { LIST_REMOVE(inm, inm_entry); IFAFREE(&ia->ia_ifa); /* release reference */ free(inm, M_IPMADDR); splx(s); return (NULL); } /* * Let IGMP know that we have joined a new IP multicast group. */ igmp_joingroup(inm); } splx(s); return (inm); } /* * Delete a multicast address record. */ void in_delmulti(inm) register struct in_multi *inm; { struct ifreq ifr; int s = splnet(); if (--inm->inm_refcount == 0) { /* * No remaining claims to this record; let IGMP know that * we are leaving the multicast group. */ igmp_leavegroup(inm); /* * Unlink from list. */ LIST_REMOVE(inm, inm_entry); IFAFREE(&inm->inm_ia->ia_ifa); /* release reference */ /* * Notify the network driver to update its multicast reception * filter. */ ((struct sockaddr_in *)&(ifr.ifr_addr))->sin_family = AF_INET; ((struct sockaddr_in *)&(ifr.ifr_addr))->sin_addr = inm->inm_addr; (*inm->inm_ifp->if_ioctl)(inm->inm_ifp, SIOCDELMULTI, (caddr_t)&ifr); free(inm, M_IPMADDR); } splx(s); }