/* $NetBSD: at_control.c,v 1.16 2006/10/25 23:30:35 elad Exp $ */ /* * Copyright (c) 1990,1994 Regents of The University of Michigan. * All Rights Reserved. * * Permission to use, copy, modify, and distribute this software and * its documentation for any purpose and without fee is hereby granted, * provided that the above copyright notice appears in all copies and * that both that copyright notice and this permission notice appear * in supporting documentation, and that the name of The University * of Michigan not be used in advertising or publicity pertaining to * distribution of the software without specific, written prior * permission. This software is supplied as is without expressed or * implied warranties of any kind. * * This product includes software developed by the University of * California, Berkeley and its contributors. * * Research Systems Unix Group * The University of Michigan * c/o Wesley Craig * 535 W. William Street * Ann Arbor, Michigan * +1-313-764-2278 * netatalk@umich.edu */ #include __KERNEL_RCSID(0, "$NetBSD: at_control.c,v 1.16 2006/10/25 23:30:35 elad Exp $"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #undef s_net #include #include #include #include #include static int aa_dorangeroute __P((struct ifaddr * ifa, u_int first, u_int last, int cmd)); static int aa_addsingleroute __P((struct ifaddr * ifa, struct at_addr * addr, struct at_addr * mask)); static int aa_delsingleroute __P((struct ifaddr * ifa, struct at_addr * addr, struct at_addr * mask)); static int aa_dosingleroute __P((struct ifaddr * ifa, struct at_addr * addr, struct at_addr * mask, int cmd, int flags)); static int at_scrub __P((struct ifnet * ifp, struct at_ifaddr * aa)); static int at_ifinit __P((struct ifnet * ifp, struct at_ifaddr * aa, struct sockaddr_at * sat)); #if 0 static void aa_clean __P((void)); #endif #define sateqaddr(a,b) ((a)->sat_len == (b)->sat_len && \ (a)->sat_family == (b)->sat_family && \ (a)->sat_addr.s_net == (b)->sat_addr.s_net && \ (a)->sat_addr.s_node == (b)->sat_addr.s_node ) int at_control(cmd, data, ifp, l) u_long cmd; caddr_t data; struct ifnet *ifp; struct lwp *l; { struct ifreq *ifr = (struct ifreq *) data; struct sockaddr_at *sat; struct netrange *nr; struct at_aliasreq *ifra = (struct at_aliasreq *) data; struct at_ifaddr *aa0; struct at_ifaddr *aa = 0; /* * If we have an ifp, then find the matching at_ifaddr if it exists */ if (ifp) for (aa = at_ifaddr.tqh_first; aa; aa = aa->aa_list.tqe_next) if (aa->aa_ifp == ifp) break; /* * In this first switch table we are basically getting ready for * the second one, by getting the atalk-specific things set up * so that they start to look more similar to other protocols etc. */ switch (cmd) { case SIOCAIFADDR: case SIOCDIFADDR: /* * If we have an appletalk sockaddr, scan forward of where * we are now on the at_ifaddr list to find one with a matching * address on this interface. * This may leave aa pointing to the first address on the * NEXT interface! */ if (ifra->ifra_addr.sat_family == AF_APPLETALK) { for (; aa; aa = aa->aa_list.tqe_next) if (aa->aa_ifp == ifp && sateqaddr(&aa->aa_addr, &ifra->ifra_addr)) break; } /* * If we a retrying to delete an addres but didn't find such, * then return with an error */ if (cmd == SIOCDIFADDR && aa == 0) return (EADDRNOTAVAIL); /* FALLTHROUGH */ case SIOCSIFADDR: /* * If we are not superuser, then we don't get to do these * ops. */ if (l && kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE, KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd, NULL) != 0) return (EPERM); sat = satosat(&ifr->ifr_addr); nr = (struct netrange *) sat->sat_zero; if (nr->nr_phase == 1) { /* * Look for a phase 1 address on this interface. * This may leave aa pointing to the first address on * the NEXT interface! */ for (; aa; aa = aa->aa_list.tqe_next) { if (aa->aa_ifp == ifp && (aa->aa_flags & AFA_PHASE2) == 0) break; } } else { /* default to phase 2 */ /* * Look for a phase 2 address on this interface. * This may leave aa pointing to the first address on * the NEXT interface! */ for (; aa; aa = aa->aa_list.tqe_next) { if (aa->aa_ifp == ifp && (aa->aa_flags & AFA_PHASE2)) break; } } if (ifp == 0) panic("at_control"); /* * If we failed to find an existing at_ifaddr entry, then we * allocate a fresh one. * XXX change this to use malloc */ if (aa == (struct at_ifaddr *) 0) { aa = (struct at_ifaddr *) malloc(sizeof(struct at_ifaddr), M_IFADDR, M_WAITOK|M_ZERO); if (aa == NULL) return (ENOBUFS); callout_init(&aa->aa_probe_ch); if ((aa0 = at_ifaddr.tqh_first) != NULL) { /* * Don't let the loopback be first, since the * first address is the machine's default * address for binding. * If it is, stick ourself in front, otherwise * go to the back of the list. */ if (aa0->aa_ifp->if_flags & IFF_LOOPBACK) { TAILQ_INSERT_HEAD(&at_ifaddr, aa, aa_list); } else { TAILQ_INSERT_TAIL(&at_ifaddr, aa, aa_list); } } else { TAILQ_INSERT_TAIL(&at_ifaddr, aa, aa_list); } IFAREF(&aa->aa_ifa); /* * Find the end of the interface's addresses * and link our new one on the end */ TAILQ_INSERT_TAIL(&ifp->if_addrlist, (struct ifaddr *) aa, ifa_list); IFAREF(&aa->aa_ifa); /* * As the at_ifaddr contains the actual sockaddrs, * and the ifaddr itself, link them al together * correctly. */ aa->aa_ifa.ifa_addr = (struct sockaddr *) &aa->aa_addr; aa->aa_ifa.ifa_dstaddr = (struct sockaddr *) &aa->aa_addr; aa->aa_ifa.ifa_netmask = (struct sockaddr *) &aa->aa_netmask; /* * Set/clear the phase 2 bit. */ if (nr->nr_phase == 1) aa->aa_flags &= ~AFA_PHASE2; else aa->aa_flags |= AFA_PHASE2; /* * and link it all together */ aa->aa_ifp = ifp; } else { /* * If we DID find one then we clobber any routes * dependent on it.. */ at_scrub(ifp, aa); } break; case SIOCGIFADDR: sat = satosat(&ifr->ifr_addr); nr = (struct netrange *) sat->sat_zero; if (nr->nr_phase == 1) { /* * If the request is specifying phase 1, then * only look at a phase one address */ for (; aa; aa = aa->aa_list.tqe_next) { if (aa->aa_ifp == ifp && (aa->aa_flags & AFA_PHASE2) == 0) break; } } else if (nr->nr_phase == 2) { /* * If the request is specifying phase 2, then * only look at a phase two address */ for (; aa; aa = aa->aa_list.tqe_next) { if (aa->aa_ifp == ifp && (aa->aa_flags & AFA_PHASE2)) break; } } else { /* * default to everything */ for (; aa; aa = aa->aa_list.tqe_next) { if (aa->aa_ifp == ifp) break; } } if (aa == (struct at_ifaddr *) 0) return (EADDRNOTAVAIL); break; } /* * By the time this switch is run we should be able to assume that * the "aa" pointer is valid when needed. */ switch (cmd) { case SIOCGIFADDR: /* * copy the contents of the sockaddr blindly. */ sat = (struct sockaddr_at *) & ifr->ifr_addr; *sat = aa->aa_addr; /* * and do some cleanups */ ((struct netrange *) &sat->sat_zero)->nr_phase = (aa->aa_flags & AFA_PHASE2) ? 2 : 1; ((struct netrange *) &sat->sat_zero)->nr_firstnet = aa->aa_firstnet; ((struct netrange *) &sat->sat_zero)->nr_lastnet = aa->aa_lastnet; break; case SIOCSIFADDR: return (at_ifinit(ifp, aa, (struct sockaddr_at *) &ifr->ifr_addr)); case SIOCAIFADDR: if (sateqaddr(&ifra->ifra_addr, &aa->aa_addr)) return 0; return (at_ifinit(ifp, aa, (struct sockaddr_at *) &ifr->ifr_addr)); case SIOCDIFADDR: at_purgeaddr((struct ifaddr *) aa, ifp); break; default: if (ifp == 0 || ifp->if_ioctl == 0) return (EOPNOTSUPP); return ((*ifp->if_ioctl) (ifp, cmd, data)); } return (0); } void at_purgeaddr(ifa, ifp) struct ifaddr *ifa; struct ifnet *ifp; { struct at_ifaddr *aa = (void *) ifa; /* * scrub all routes.. didn't we just DO this? XXX yes, del it * XXX above XXX not necessarily true anymore */ at_scrub(ifp, aa); /* * remove the ifaddr from the interface */ TAILQ_REMOVE(&ifp->if_addrlist, (struct ifaddr *) aa, ifa_list); IFAFREE(&aa->aa_ifa); TAILQ_REMOVE(&at_ifaddr, aa, aa_list); IFAFREE(&aa->aa_ifa); } void at_purgeif(ifp) struct ifnet *ifp; { struct ifaddr *ifa, *nifa; for (ifa = TAILQ_FIRST(&ifp->if_addrlist); ifa != NULL; ifa = nifa) { nifa = TAILQ_NEXT(ifa, ifa_list); if (ifa->ifa_addr->sa_family != AF_APPLETALK) continue; at_purgeaddr(ifa, ifp); } } /* * Given an interface and an at_ifaddr (supposedly on that interface) remove * any routes that depend on this. Why ifp is needed I'm not sure, as * aa->at_ifaddr.ifa_ifp should be the same. */ static int at_scrub(ifp, aa) struct ifnet *ifp; struct at_ifaddr *aa; { int error = 0; if (aa->aa_flags & AFA_ROUTE) { if (ifp->if_flags & IFF_LOOPBACK) error = aa_delsingleroute(&aa->aa_ifa, &aa->aa_addr.sat_addr, &aa->aa_netmask.sat_addr); else if (ifp->if_flags & IFF_POINTOPOINT) error = rtinit(&aa->aa_ifa, RTM_DELETE, RTF_HOST); else if (ifp->if_flags & IFF_BROADCAST) error = aa_dorangeroute(&aa->aa_ifa, ntohs(aa->aa_firstnet), ntohs(aa->aa_lastnet), RTM_DELETE); aa->aa_ifa.ifa_flags &= ~IFA_ROUTE; aa->aa_flags &= ~AFA_ROUTE; } return error; } /* * given an at_ifaddr,a sockaddr_at and an ifp, * bang them all together at high speed and see what happens */ static int at_ifinit(ifp, aa, sat) struct ifnet *ifp; struct at_ifaddr *aa; struct sockaddr_at *sat; { struct netrange nr, onr; struct sockaddr_at oldaddr; int s = splnet(), error = 0, i, j; int netinc, nodeinc, nnets; u_short net; /* * save the old addresses in the at_ifaddr just in case we need them. */ oldaddr = aa->aa_addr; onr.nr_firstnet = aa->aa_firstnet; onr.nr_lastnet = aa->aa_lastnet; /* * take the address supplied as an argument, and add it to the * at_ifnet (also given). Remember ing to update * those parts of the at_ifaddr that need special processing */ bzero(AA_SAT(aa), sizeof(struct sockaddr_at)); bcopy(sat->sat_zero, &nr, sizeof(struct netrange)); bcopy(sat->sat_zero, AA_SAT(aa)->sat_zero, sizeof(struct netrange)); nnets = ntohs(nr.nr_lastnet) - ntohs(nr.nr_firstnet) + 1; aa->aa_firstnet = nr.nr_firstnet; aa->aa_lastnet = nr.nr_lastnet; #ifdef NETATALKDEBUG printf("at_ifinit: %s: %u.%u range %u-%u phase %d\n", ifp->if_xname, ntohs(sat->sat_addr.s_net), sat->sat_addr.s_node, ntohs(aa->aa_firstnet), ntohs(aa->aa_lastnet), (aa->aa_flags & AFA_PHASE2) ? 2 : 1); #endif /* * We could eliminate the need for a second phase 1 probe (post * autoconf) if we check whether we're resetting the node. Note * that phase 1 probes use only nodes, not net.node pairs. Under * phase 2, both the net and node must be the same. */ AA_SAT(aa)->sat_len = sat->sat_len; AA_SAT(aa)->sat_family = AF_APPLETALK; if (ifp->if_flags & IFF_LOOPBACK) { AA_SAT(aa)->sat_addr.s_net = sat->sat_addr.s_net; AA_SAT(aa)->sat_addr.s_node = sat->sat_addr.s_node; #if 0 } else if (fp->if_flags & IFF_POINTOPOINT) { /* unimplemented */ /* * we'd have to copy the dstaddr field over from the sat * but it's not clear that it would contain the right info.. */ #endif } else { /* * We are a normal (probably ethernet) interface. * apply the new address to the interface structures etc. * We will probe this address on the net first, before * applying it to ensure that it is free.. If it is not, then * we will try a number of other randomly generated addresses * in this net and then increment the net. etc.etc. until * we find an unused address. */ aa->aa_flags |= AFA_PROBING; /* if not loopback we Must * probe? */ if (aa->aa_flags & AFA_PHASE2) { if (sat->sat_addr.s_net == ATADDR_ANYNET) { /* * If we are phase 2, and the net was not * specified * then we select a random net * within the supplied netrange. * XXX use /dev/random? */ if (nnets != 1) { net = ntohs(nr.nr_firstnet) + time_second % (nnets - 1); } else { net = ntohs(nr.nr_firstnet); } } else { /* * if a net was supplied, then check that it * is within the netrange. If it is not then * replace the old values and return an error */ if (ntohs(sat->sat_addr.s_net) < ntohs(nr.nr_firstnet) || ntohs(sat->sat_addr.s_net) > ntohs(nr.nr_lastnet)) { aa->aa_addr = oldaddr; aa->aa_firstnet = onr.nr_firstnet; aa->aa_lastnet = onr.nr_lastnet; splx(s); return (EINVAL); } /* * otherwise just use the new net number.. */ net = ntohs(sat->sat_addr.s_net); } } else { /* * we must be phase one, so just use whatever we were * given. I guess it really isn't going to be used... * RIGHT? */ net = ntohs(sat->sat_addr.s_net); } /* * set the node part of the address into the ifaddr. If it's * not specified, be random about it... XXX use /dev/random? */ if (sat->sat_addr.s_node == ATADDR_ANYNODE) { AA_SAT(aa)->sat_addr.s_node = time_second; } else { AA_SAT(aa)->sat_addr.s_node = sat->sat_addr.s_node; } /* * step through the nets in the range starting at the * (possibly random) start point. */ for (i = nnets, netinc = 1; i > 0; net = ntohs(nr.nr_firstnet) + ((net - ntohs(nr.nr_firstnet) + netinc) % nnets), i--) { AA_SAT(aa)->sat_addr.s_net = htons(net); /* * using a rather strange stepping method, * stagger through the possible node addresses * Once again, starting at the (possibly random) * initial node address. */ for (j = 0, nodeinc = time_second | 1; j < 256; j++, AA_SAT(aa)->sat_addr.s_node += nodeinc) { if (AA_SAT(aa)->sat_addr.s_node > 253 || AA_SAT(aa)->sat_addr.s_node < 1) { continue; } aa->aa_probcnt = 10; /* * start off the probes as an asynchronous * activity. though why wait 200mSec? */ callout_reset(&aa->aa_probe_ch, hz / 5, aarpprobe, ifp); if (tsleep(aa, PPAUSE | PCATCH, "at_ifinit", 0)) { /* * theoretically we shouldn't time out * here so if we returned with an error. */ printf("at_ifinit: timeout?!\n"); aa->aa_addr = oldaddr; aa->aa_firstnet = onr.nr_firstnet; aa->aa_lastnet = onr.nr_lastnet; splx(s); return (EINTR); } /* * The async activity should have woken us * up. We need to see if it was successful in * finding a free spot, or if we need to * iterate to the next address to try. */ if ((aa->aa_flags & AFA_PROBING) == 0) break; } /* * of course we need to break out through two loops... */ if ((aa->aa_flags & AFA_PROBING) == 0) break; /* reset node for next network */ AA_SAT(aa)->sat_addr.s_node = time_second; } /* * if we are still trying to probe, then we have finished all * the possible addresses, so we need to give up */ if (aa->aa_flags & AFA_PROBING) { aa->aa_addr = oldaddr; aa->aa_firstnet = onr.nr_firstnet; aa->aa_lastnet = onr.nr_lastnet; splx(s); return (EADDRINUSE); } } /* * Now that we have selected an address, we need to tell the * interface about it, just in case it needs to adjust something. */ if (ifp->if_ioctl && (error = (*ifp->if_ioctl) (ifp, SIOCSIFADDR, (caddr_t) aa))) { /* * of course this could mean that it objects violently * so if it does, we back out again.. */ aa->aa_addr = oldaddr; aa->aa_firstnet = onr.nr_firstnet; aa->aa_lastnet = onr.nr_lastnet; splx(s); return (error); } /* * set up the netmask part of the at_ifaddr and point the appropriate * pointer in the ifaddr to it. probably pointless, but what the * heck.. XXX */ bzero(&aa->aa_netmask, sizeof(aa->aa_netmask)); aa->aa_netmask.sat_len = sizeof(struct sockaddr_at); aa->aa_netmask.sat_family = AF_APPLETALK; aa->aa_netmask.sat_addr.s_net = 0xffff; aa->aa_netmask.sat_addr.s_node = 0; #if 0 aa->aa_ifa.ifa_netmask = (struct sockaddr *) &(aa->aa_netmask);/* XXX */ #endif /* * Initialize broadcast (or remote p2p) address */ bzero(&aa->aa_broadaddr, sizeof(aa->aa_broadaddr)); aa->aa_broadaddr.sat_len = sizeof(struct sockaddr_at); aa->aa_broadaddr.sat_family = AF_APPLETALK; aa->aa_ifa.ifa_metric = ifp->if_metric; if (ifp->if_flags & IFF_BROADCAST) { aa->aa_broadaddr.sat_addr.s_net = htons(0); aa->aa_broadaddr.sat_addr.s_node = 0xff; aa->aa_ifa.ifa_broadaddr = (struct sockaddr *) &aa->aa_broadaddr; /* add the range of routes needed */ error = aa_dorangeroute(&aa->aa_ifa, ntohs(aa->aa_firstnet), ntohs(aa->aa_lastnet), RTM_ADD); } else if (ifp->if_flags & IFF_POINTOPOINT) { struct at_addr rtaddr, rtmask; bzero(&rtaddr, sizeof(rtaddr)); bzero(&rtmask, sizeof(rtmask)); /* fill in the far end if we know it here XXX */ aa->aa_ifa.ifa_dstaddr = (struct sockaddr *) & aa->aa_dstaddr; error = aa_addsingleroute(&aa->aa_ifa, &rtaddr, &rtmask); } else if (ifp->if_flags & IFF_LOOPBACK) { struct at_addr rtaddr, rtmask; bzero(&rtaddr, sizeof(rtaddr)); bzero(&rtmask, sizeof(rtmask)); rtaddr.s_net = AA_SAT(aa)->sat_addr.s_net; rtaddr.s_node = AA_SAT(aa)->sat_addr.s_node; rtmask.s_net = 0xffff; rtmask.s_node = 0x0; error = aa_addsingleroute(&aa->aa_ifa, &rtaddr, &rtmask); } /* * of course if we can't add these routes we back out, but it's getting * risky by now XXX */ if (error) { at_scrub(ifp, aa); aa->aa_addr = oldaddr; aa->aa_firstnet = onr.nr_firstnet; aa->aa_lastnet = onr.nr_lastnet; splx(s); return (error); } /* * note that the address has a route associated with it.... */ aa->aa_ifa.ifa_flags |= IFA_ROUTE; aa->aa_flags |= AFA_ROUTE; splx(s); return (0); } /* * check whether a given address is a broadcast address for us.. */ int at_broadcast(sat) struct sockaddr_at *sat; { struct at_ifaddr *aa; /* * If the node is not right, it can't be a broadcast */ if (sat->sat_addr.s_node != ATADDR_BCAST) return 0; /* * If the node was right then if the net is right, it's a broadcast */ if (sat->sat_addr.s_net == ATADDR_ANYNET) return 1; /* * failing that, if the net is one we have, it's a broadcast as well. */ for (aa = at_ifaddr.tqh_first; aa; aa = aa->aa_list.tqe_next) { if ((aa->aa_ifp->if_flags & IFF_BROADCAST) && (ntohs(sat->sat_addr.s_net) >= ntohs(aa->aa_firstnet) && ntohs(sat->sat_addr.s_net) <= ntohs(aa->aa_lastnet))) return 1; } return 0; } /* * aa_dorangeroute() * * Add a route for a range of networks from bot to top - 1. * Algorithm: * * Split the range into two subranges such that the middle * of the two ranges is the point where the highest bit of difference * between the two addresses, makes it's transition * Each of the upper and lower ranges might not exist, or might be * representable by 1 or more netmasks. In addition, if both * ranges can be represented by the same netmask, then teh can be merged * by using the next higher netmask.. */ static int aa_dorangeroute(ifa, bot, top, cmd) struct ifaddr *ifa; u_int bot; u_int top; int cmd; { u_int mask1; struct at_addr addr; struct at_addr mask; int error; /* * slight sanity check */ if (bot > top) return (EINVAL); addr.s_node = 0; mask.s_node = 0; /* * just start out with the lowest boundary * and keep extending the mask till it's too big. */ while (bot <= top) { mask1 = 1; while (((bot & ~mask1) >= bot) && ((bot | mask1) <= top)) { mask1 <<= 1; mask1 |= 1; } mask1 >>= 1; mask.s_net = htons(~mask1); addr.s_net = htons(bot); if (cmd == RTM_ADD) { error = aa_addsingleroute(ifa, &addr, &mask); if (error) { /* XXX clean up? */ return (error); } } else { error = aa_delsingleroute(ifa, &addr, &mask); } bot = (bot | mask1) + 1; } return 0; } static int aa_addsingleroute(ifa, addr, mask) struct ifaddr *ifa; struct at_addr *addr; struct at_addr *mask; { int error; #ifdef NETATALKDEBUG printf("aa_addsingleroute: %x.%x mask %x.%x ...", ntohs(addr->s_net), addr->s_node, ntohs(mask->s_net), mask->s_node); #endif error = aa_dosingleroute(ifa, addr, mask, RTM_ADD, RTF_UP); #ifdef NETATALKDEBUG if (error) printf("aa_addsingleroute: error %d\n", error); #endif return (error); } static int aa_delsingleroute(ifa, addr, mask) struct ifaddr *ifa; struct at_addr *addr; struct at_addr *mask; { int error; #ifdef NETATALKDEBUG printf("aa_delsingleroute: %x.%x mask %x.%x ...", ntohs(addr->s_net), addr->s_node, ntohs(mask->s_net), mask->s_node); #endif error = aa_dosingleroute(ifa, addr, mask, RTM_DELETE, 0); #ifdef NETATALKDEBUG if (error) printf("aa_delsingleroute: error %d\n", error); #endif return (error); } static int aa_dosingleroute(ifa, at_addr, at_mask, cmd, flags) struct ifaddr *ifa; struct at_addr *at_addr; struct at_addr *at_mask; int cmd; int flags; { struct sockaddr_at addr, mask, *gate; bzero(&addr, sizeof(addr)); bzero(&mask, sizeof(mask)); addr.sat_family = AF_APPLETALK; addr.sat_len = sizeof(struct sockaddr_at); addr.sat_addr.s_net = at_addr->s_net; addr.sat_addr.s_node = at_addr->s_node; mask.sat_family = AF_APPLETALK; mask.sat_len = sizeof(struct sockaddr_at); mask.sat_addr.s_net = at_mask->s_net; mask.sat_addr.s_node = at_mask->s_node; if (at_mask->s_node) { gate = satosat(ifa->ifa_dstaddr); flags |= RTF_HOST; } else { gate = satosat(ifa->ifa_addr); } #ifdef NETATALKDEBUG printf("on %s %x.%x\n", (flags & RTF_HOST) ? "host" : "net", ntohs(gate->sat_addr.s_net), gate->sat_addr.s_node); #endif return (rtrequest(cmd, (struct sockaddr *) &addr, (struct sockaddr *) gate, (struct sockaddr *) &mask, flags, NULL)); } #if 0 static void aa_clean() { struct at_ifaddr *aa; struct ifaddr *ifa; struct ifnet *ifp; while (aa = at_ifaddr) { ifp = aa->aa_ifp; at_scrub(ifp, aa); at_ifaddr = aa->aa_next; if ((ifa = ifp->if_addrlist) == (struct ifaddr *) aa) { ifp->if_addrlist = ifa->ifa_next; } else { while (ifa->ifa_next && (ifa->ifa_next != (struct ifaddr *) aa)) { ifa = ifa->ifa_next; } if (ifa->ifa_next) { ifa->ifa_next = ((struct ifaddr *) aa)->ifa_next; } else { panic("at_entry"); } } } } #endif