/* * Copyright (c) 1982, 1986, 1991 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. * * from: @(#)in.c 7.17 (Berkeley) 4/20/91 * $Id: in.c,v 1.10 1994/02/10 17:25:16 mycroft Exp $ */ #include #include #include #include #include #include #include #include #include #include static int in_ifinit __P((struct ifnet *, struct in_ifaddr *, struct sockaddr_in *, int)); static void in_ifscrub __P((struct ifnet *, struct in_ifaddr *)); #ifdef INET /* * Formulate an Internet address from network + host. */ struct in_addr in_makeaddr(net, host) u_long net, host; { register struct in_ifaddr *ia; register u_long mask; u_long addr; if (IN_CLASSA(net)) mask = IN_CLASSA_HOST; else if (IN_CLASSB(net)) mask = IN_CLASSB_HOST; else mask = IN_CLASSC_HOST; for (ia = in_ifaddr; ia; ia = ia->ia_next) if ((ia->ia_netmask & net) == ia->ia_net) { mask = ~ia->ia_subnetmask; break; } addr = htonl(net | (host & mask)); return (*(struct in_addr *)&addr); } /* * Return the network number from an internet address. */ u_long in_netof(in) struct in_addr in; { register u_long i = ntohl(in.s_addr); register u_long net; register struct in_ifaddr *ia; if (IN_CLASSA(i)) net = i & IN_CLASSA_NET; else if (IN_CLASSB(i)) net = i & IN_CLASSB_NET; else if (IN_CLASSD(i)) net = i & IN_CLASSD_NET; else if (IN_CLASSC(i)) net = i & IN_CLASSC_NET; else return (0); /* * Check whether network is a subnet; * if so, return subnet number. */ for (ia = in_ifaddr; ia; ia = ia->ia_next) if (net == ia->ia_net) return (i & ia->ia_subnetmask); return (net); } /* * Compute and save network mask as sockaddr from an internet address. */ void in_sockmaskof(in, sockmask) struct in_addr in; register struct sockaddr_in *sockmask; { register u_long net; register u_long mask; { register u_long i = ntohl(in.s_addr); if (i == 0) net = 0, mask = 0; else if (IN_CLASSA(i)) net = i & IN_CLASSA_NET, mask = IN_CLASSA_NET; else if (IN_CLASSB(i)) net = i & IN_CLASSB_NET, mask = IN_CLASSB_NET; else if (IN_CLASSC(i)) net = i & IN_CLASSC_NET, mask = IN_CLASSC_NET; else net = i, mask = -1; } { register struct in_ifaddr *ia; /* * Check whether network is a subnet; * if so, return subnet number. */ for (ia = in_ifaddr; ia; ia = ia->ia_next) if (net == ia->ia_net) mask = ia->ia_subnetmask; } { register char *cpbase = (char *)&(sockmask->sin_addr); register char *cp = (char *)(1 + &(sockmask->sin_addr)); sockmask->sin_addr.s_addr = htonl(mask); sockmask->sin_len = 0; while (--cp >= cpbase) if (*cp) { sockmask->sin_len = 1 + cp - (caddr_t)sockmask; break; } } } /* * Return the host portion of an internet address. */ u_long in_lnaof(in) struct in_addr in; { register u_long i = ntohl(in.s_addr); register u_long net, host; register struct in_ifaddr *ia; if (IN_CLASSA(i)) { net = i & IN_CLASSA_NET; host = i & IN_CLASSA_HOST; } else if (IN_CLASSB(i)) { net = i & IN_CLASSB_NET; host = i & IN_CLASSB_HOST; } else if (IN_CLASSC(i)) { net = i & IN_CLASSC_NET; host = i & IN_CLASSC_HOST; } else if (IN_CLASSD(i)) { net = i & IN_CLASSD_NET; host = i & IN_CLASSD_HOST; } else return (i); /* * Check whether network is a subnet; * if so, use the modified interpretation of `host'. */ for (ia = in_ifaddr; ia; ia = ia->ia_next) if (net == ia->ia_net) return (host &~ ia->ia_subnetmask); return (host); } #ifndef SUBNETSARELOCAL #define SUBNETSARELOCAL 1 #endif int subnetsarelocal = SUBNETSARELOCAL; /* * 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_ifaddr; ia; ia = ia->ia_next) if ((i & ia->ia_netmask) == ia->ia_net) return (1); } else { for (ia = in_ifaddr; ia; ia = ia->ia_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)) return (0); if (IN_CLASSA(i)) { net = i & IN_CLASSA_NET; if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT)) return (0); } return (1); } int in_interfaces; /* number of external internet interfaces */ extern struct ifnet loif; /* * 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; int cmd; caddr_t data; register struct ifnet *ifp; { register struct ifreq *ifr = (struct ifreq *)data; register struct in_ifaddr *ia = 0; register struct ifaddr *ifa; struct in_ifaddr *oia; struct in_aliasreq *ifra = (struct in_aliasreq *)data; struct mbuf *m; struct sockaddr_in oldaddr; int error, hostIsNew, maskIsNew; u_long i; /* * Find address for this interface, if it exists. */ if (ifp) for (ia = in_ifaddr; ia; ia = ia->ia_next) if (ia->ia_ifp == ifp) break; switch (cmd) { case SIOCAIFADDR: case SIOCDIFADDR: if (ifra->ifra_addr.sin_family == AF_INET) for (oia = ia; ia; ia = ia->ia_next) { if (ia->ia_ifp == ifp && ia->ia_addr.sin_addr.s_addr == ifra->ifra_addr.sin_addr.s_addr) break; } 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) { m = m_getclr(M_WAIT, MT_IFADDR); if (m == (struct mbuf *)NULL) return (ENOBUFS); if (ia = in_ifaddr) { for ( ; ia->ia_next; ia = ia->ia_next) ; ia->ia_next = mtod(m, struct in_ifaddr *); } else in_ifaddr = mtod(m, struct in_ifaddr *); ia = mtod(m, struct in_ifaddr *); if (ifa = ifp->if_addrlist) { for ( ; ifa->ifa_next; ifa = ifa->ifa_next) ; ifa->ifa_next = (struct ifaddr *) ia; } else ifp->if_addrlist = (struct ifaddr *) ia; ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr; ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr; ia->ia_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 != &loif) in_interfaces++; } 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; default: return (EOPNOTSUPP); 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, 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: in_ifscrub(ifp, ia); if ((ifa = ifp->if_addrlist) == (struct ifaddr *)ia) ifp->if_addrlist = ifa->ifa_next; else { while (ifa->ifa_next && (ifa->ifa_next != (struct ifaddr *)ia)) ifa = ifa->ifa_next; if (ifa->ifa_next) ifa->ifa_next = ((struct ifaddr *)ia)->ifa_next; else printf("Couldn't unlink inifaddr from ifp\n"); } oia = ia; if (oia == (ia = in_ifaddr)) in_ifaddr = ia->ia_next; else { while (ia->ia_next && (ia->ia_next != oia)) ia = ia->ia_next; if (ia->ia_next) ia->ia_next = oia->ia_next; else printf("Didn't unlink inifadr from list\n"); } (void) m_free(dtom(oia)); 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; { register u_long i = ntohl(sin->sin_addr.s_addr); struct sockaddr_in oldaddr; int s = splimp(), error, flags = RTF_UP; 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, 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; ia->ia_net = i & ia->ia_netmask; /* * The subnet mask includes at least the standard network part, * but may already have been set to a larger value. */ ia->ia_subnetmask |= ia->ia_netmask; ia->ia_subnet = i & ia->ia_subnetmask; ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask); { register char *cp = (char *) (1 + &(ia->ia_sockmask.sin_addr)); register char *cpbase = (char *) &(ia->ia_sockmask.sin_addr); while (--cp >= cpbase) if (*cp) { ia->ia_sockmask.sin_len = 1 + cp - (char *) &(ia->ia_sockmask); break; } } /* * Add route for the network. */ if (ifp->if_flags & IFF_BROADCAST) { ia->ia_broadaddr.sin_addr = in_makeaddr(ia->ia_subnet, INADDR_BROADCAST); ia->ia_netbroadcast.s_addr = htonl(ia->ia_net | (INADDR_BROADCAST &~ 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; /* * If the interface supports multicast, join the "all hosts" * multicast group on that interface. */ if (ifp->if_flags & IFF_MULTICAST) { struct in_addr addr; addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP); in_addmulti(&addr, ifp); } return (error); } /* * Return address info for specified internet network. */ struct in_ifaddr * in_iaonnetof(net) u_long net; { register struct in_ifaddr *ia; for (ia = in_ifaddr; ia; ia = ia->ia_next) if (ia->ia_subnet == net) return (ia); return ((struct in_ifaddr *)0); } /* * Return 1 if the address might be a local broadcast address. */ int in_broadcast(in) struct in_addr in; { register struct in_ifaddr *ia; u_long t; /* * Look through the list of addresses for a match * with a broadcast address. */ for (ia = in_ifaddr; ia; ia = ia->ia_next) if (ia->ia_ifp->if_flags & IFF_BROADCAST) { if (ia->ia_broadaddr.sin_addr.s_addr == in.s_addr) return (1); /* * Check for old-style (host 0) broadcast. */ if ((t = ntohl(in.s_addr)) == ia->ia_subnet || t == ia->ia_net) return (1); } if (in.s_addr == INADDR_BROADCAST || in.s_addr == INADDR_ANY) return (1); return (0); } /* * 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; inm->inm_next = ia->ia_multiaddrs; ia->ia_multiaddrs = inm; /* * 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) { ia->ia_multiaddrs = inm->inm_next; 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. */ int in_delmulti(inm) register struct in_multi *inm; { register struct in_multi **p; 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. */ for (p = &inm->inm_ia->ia_multiaddrs; *p != inm; p = &(*p)->inm_next) continue; *p = (*p)->inm_next; /* * 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); } #endif