/* * Copyright (c) 1982, 1986, 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. 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. * * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include static struct mbuf *ip_insertoptions(); int ip_optcopy(); #if defined(IPFILTER_LKM) || defined(IPFILTER) extern int (*fr_checkp)(), fr_check(); #endif /* * IP output. The packet in mbuf chain m contains a skeletal IP * header (with len, off, ttl, proto, tos, src, dst). * The mbuf chain containing the packet will be freed. * The mbuf opt, if present, will not be freed. */ #ifdef MULTICAST ip_output(m0, opt, ro, flags, mopts) #else ip_output(m0, opt, ro, flags) #endif /* MULTICAST */ struct mbuf *m0; struct mbuf *opt; struct route *ro; int flags; #ifdef MULTICAST struct mbuf *mopts; #endif /* MULTICAST */ { register struct ip *ip, *mhip; register struct ifnet *ifp; register struct mbuf *m = m0; register int hlen = sizeof (struct ip); int len, off, error = 0; struct route iproute; struct sockaddr_in *dst = NULL; if (opt) { m = ip_insertoptions(m, opt, &len); hlen = len; } ip = mtod(m, struct ip *); /* * Fill in IP header. */ if ((flags & IP_FORWARDING) == 0) { ip->ip_v = IPVERSION; ip->ip_off &= IP_DF; ip->ip_id = htons(ip_id++); ip->ip_hl = hlen >> 2; } else hlen = ip->ip_hl << 2; /* * Route packet. */ if (ro == 0) { ro = &iproute; bzero((caddr_t)ro, sizeof (*ro)); } dst = (struct sockaddr_in *)&ro->ro_dst; /* * If there is a cached route, * check that it is to the same destination * and is still up. If not, free it and try again. */ if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 || dst->sin_addr.s_addr != ip->ip_dst.s_addr)) { RTFREE(ro->ro_rt); ro->ro_rt = (struct rtentry *)0; } if (ro->ro_rt == 0) { dst->sin_family = AF_INET; dst->sin_addr = ip->ip_dst; } /* * If routing to interface only, * short circuit routing lookup. */ if (flags & IP_ROUTETOIF) { struct in_ifaddr *ia; ia = (struct in_ifaddr *)ifa_ifwithdstaddr(dst); if (ia == 0) ia = in_iaonnetof(in_netof(ip->ip_dst)); if (ia == 0) { error = ENETUNREACH; goto bad; } ifp = ia->ia_ifp; } else { if (ro->ro_rt == 0) rtalloc(ro); if (ro->ro_rt == 0 || (ifp = ro->ro_rt->rt_ifp) == 0) { if (in_localaddr(ip->ip_dst)) error = EHOSTUNREACH; else error = ENETUNREACH; goto bad; } ro->ro_rt->rt_use++; if (ro->ro_rt->rt_flags & RTF_GATEWAY) dst = (struct sockaddr_in *)&ro->ro_rt->rt_gateway; } #ifdef MULTICAST if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { struct ip_moptions *imo; struct in_multi *inm; extern struct ifnet loif; #ifdef MROUTING extern struct socket *ip_mrouter; #ifdef RSVP_ISI extern int rsvp_on; extern struct ifnet *mcast_ifp(); #endif /* RSVP_ISI */ #endif /* MROUTING */ /* * IP destination address is multicast. Make sure "dst" * still points to the address in "ro". (It may have been * changed to point to a gateway address, above.) */ dst = (struct sockaddr_in *)&ro->ro_dst; /* * See if the caller provided any multicast options */ if ((flags & IP_MULTICASTOPTS) && mopts != NULL) { imo = mtod(mopts, struct ip_moptions *); ip->ip_ttl = imo->imo_multicast_ttl; if (imo->imo_multicast_ifp != NULL) ifp = imo->imo_multicast_ifp; #ifdef RSVP_ISI if (imo->imo_multicast_vif != -1) ip->ip_src.s_addr = ip_mcast_src(imo->imo_multicast_vif); #endif /* RSVP_ISI */ } else { imo = NULL; ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; } /* * Confirm that the outgoing interface supports multicast. */ #ifdef RSVP_ISI if ((imo == NULL) || (imo->imo_multicast_vif == -1)) #endif /* RSVP_ISI */ if ((ifp->if_flags & IFF_MULTICAST) == 0) { error = ENETUNREACH; goto bad; } /* * If source address not specified yet, use address * of outgoing interface. */ if (ip->ip_src.s_addr == INADDR_ANY) { register struct in_ifaddr *ia; for (ia = in_ifaddr; ia; ia = ia->ia_next) if (ia->ia_ifp == ifp) { ip->ip_src = IA_SIN(ia)->sin_addr; break; } } IN_LOOKUP_MULTI(ip->ip_dst, ifp, inm); if (inm != NULL && (imo == NULL || imo->imo_multicast_loop)) { /* * If we belong to the destination multicast group * on the outgoing interface, and the caller did not * forbid loopback, loop back a copy. */ ip_mloopback(ifp, m, dst); } #ifdef MROUTING else if (ip_mrouter && (flags & IP_FORWARDING) == 0) { /* * If we are acting as a multicast router, perform * multicast forwarding as if the packet had just * arrived on the interface to which we are about * to send. The multicast forwarding function * recursively calls this function, using the * IP_FORWARDING flag to prevent infinite recursion. * * Multicasts that are looped back by ip_mloopback(), * above, will be forwarded by the ip_input() routine, * if necessary. */ #ifdef RSVP_ISI /* * Check if rsvp daemon is running. If not, don't * set ip_moptions. This ensures that the packet * is multicast and not just sent down one link * as prescribed by rsvpd. */ if (!rsvp_on) imo = NULL; if (ip_mforward(ip, ifp, m, imo) != 0) { #else if (ip_mforward(ip, ifp, m) != 0) { #endif /* RSVP_ISI */ m_freem(m); goto done; } } #endif /* MROUTING */ /* * Multicasts with a time-to-live of zero may be looped- * back, above, but must not be transmitted on a network. * Also, multicasts addressed to the loopback interface * are not sent -- the above call to ip_mloopback() will * loop back a copy if this host actually belongs to the * destination group on the loopback interface. */ if (ip->ip_ttl == 0 || ifp == &loif) { m_freem(m); goto done; } goto sendit; } #endif /* MULTICAST */ /* * If source address not specified yet, use address * of outgoing interface. */ if (ip->ip_src.s_addr == INADDR_ANY) { register struct in_ifaddr *ia; for (ia = in_ifaddr; ia; ia = ia->ia_next) if (ia->ia_ifp == ifp) { ip->ip_src = IA_SIN(ia)->sin_addr; break; } } /* * Look for broadcast address and * and verify user is allowed to send * such a packet. */ if (in_broadcast(dst->sin_addr)) { if ((ifp->if_flags & IFF_BROADCAST) == 0) { error = EADDRNOTAVAIL; goto bad; } #if !defined(sun) if ((flags & IP_ALLOWBROADCAST) == 0) { error = EACCES; goto bad; } #endif /* don't allow broadcast messages to be fragmented */ if (ip->ip_len > ifp->if_mtu) { error = EMSGSIZE; goto bad; } } #ifdef MULTICAST sendit: #endif /* MULTICAST */ /* * looks like most checking has been done now...do a filter check */ #if defined(IPFILTER_LKM) || defined(IPFILTER) if (fr_checkp) { struct mbuf *m1 = m; if ((error = (*fr_checkp)(ip, hlen, ifp, 1, &m1)) || !m1) goto done; ip = mtod(m = m1, struct ip *); } #endif /* * If small enough for interface, can just send directly. */ if (ip->ip_len <= ifp->if_mtu) { #ifndef sparc ip->ip_len = htons((u_short)ip->ip_len); ip->ip_off = htons((u_short)ip->ip_off); #endif ip->ip_sum = 0; ip->ip_sum = in_cksum(m, hlen); error = (*ifp->if_output)(ifp, m, (struct sockaddr *)dst); goto done; } /* * Too large for interface; fragment if possible. * Must be able to put at least 8 bytes per fragment. */ if (ip->ip_off & IP_DF) { error = EMSGSIZE; goto bad; } len = (ifp->if_mtu - hlen) &~ 7; if (len < 8) { error = EMSGSIZE; goto bad; } { int mhlen, firstlen = len; struct mbuf **mnext = &m->m_act; /* * Loop through length of segment after first fragment, * make new header and copy data of each part and link onto chain. */ m0 = m; mhlen = sizeof (struct ip); for (off = hlen + len; off < ip->ip_len; off += len) { MGET(m, M_DONTWAIT, MT_HEADER); if (m == 0) { error = ENOBUFS; goto bad; } m->m_off = MMAXOFF - hlen; mhip = mtod(m, struct ip *); *mhip = *ip; if (hlen > sizeof (struct ip)) { mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip); mhip->ip_hl = mhlen >> 2; } m->m_len = mhlen; mhip->ip_off = ((off - hlen) >> 3) + (ip->ip_off & ~IP_MF); if (ip->ip_off & IP_MF) mhip->ip_off |= IP_MF; if (off + len >= ip->ip_len) len = ip->ip_len - off; else mhip->ip_off |= IP_MF; mhip->ip_len = htons((u_short)(len + mhlen)); m->m_next = m_copy(m0, off, len); if (m->m_next == 0) { error = ENOBUFS; /* ??? */ goto sendorfree; } #ifndef sparc mhip->ip_off = htons((u_short)mhip->ip_off); #endif mhip->ip_sum = 0; mhip->ip_sum = in_cksum(m, mhlen); *mnext = m; mnext = &m->m_act; } /* * Update first fragment by trimming what's been copied out * and updating header, then send each fragment (in order). */ m_adj(m0, hlen + firstlen - ip->ip_len); ip->ip_len = htons((u_short)(hlen + firstlen)); ip->ip_off = htons((u_short)(ip->ip_off | IP_MF)); ip->ip_sum = 0; ip->ip_sum = in_cksum(m0, hlen); sendorfree: for (m = m0; m; m = m0) { m0 = m->m_act; m->m_act = 0; if (error == 0) error = (*ifp->if_output)(ifp, m, (struct sockaddr *)dst); else m_freem(m); } } done: if (ro == &iproute && (flags & IP_ROUTETOIF) == 0 && ro->ro_rt) RTFREE(ro->ro_rt); return (error); bad: m_freem(m0); goto done; } /* * Insert IP options into preformed packet. * Adjust IP destination as required for IP source routing, * as indicated by a non-zero in_addr at the start of the options. */ static struct mbuf * ip_insertoptions(m, opt, phlen) register struct mbuf *m; struct mbuf *opt; int *phlen; { register struct ipoption *p = mtod(opt, struct ipoption *); struct mbuf *n; register struct ip *ip = mtod(m, struct ip *); unsigned optlen; optlen = opt->m_len - sizeof(p->ipopt_dst); if (p->ipopt_dst.s_addr) ip->ip_dst = p->ipopt_dst; if (m->m_off >= MMAXOFF || MMINOFF + optlen > m->m_off) { MGET(n, M_DONTWAIT, MT_HEADER); if (n == 0) return (m); m->m_len -= sizeof(struct ip); m->m_off += sizeof(struct ip); n->m_next = m; m = n; m->m_off = MMAXOFF - sizeof(struct ip) - optlen; m->m_len = optlen + sizeof(struct ip); bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); } else { m->m_off -= optlen; m->m_len += optlen; ovbcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); } ip = mtod(m, struct ip *); bcopy((caddr_t)p->ipopt_list, (caddr_t)(ip + 1), (unsigned)optlen); *phlen = sizeof(struct ip) + optlen; ip->ip_len += optlen; return (m); } /* * Copy options from ip to jp, * omitting those not copied during fragmentation. */ int ip_optcopy(ip, jp) struct ip *ip, *jp; { register u_char *cp, *dp; int opt, optlen, cnt; cp = (u_char *)(ip + 1); dp = (u_char *)(jp + 1); cnt = (ip->ip_hl << 2) - sizeof (struct ip); for (; cnt > 0; cnt -= optlen, cp += optlen) { opt = cp[0]; if (opt == IPOPT_EOL) break; if (opt == IPOPT_NOP) { /* Preserve for IP mcast tunnel's LSRR alignment. */ *dp++ = IPOPT_NOP; optlen = 1; continue; } else optlen = cp[IPOPT_OLEN]; /* bogus lengths should have been caught by ip_dooptions */ if (optlen > cnt) optlen = cnt; if (IPOPT_COPIED(opt)) { bcopy((caddr_t)cp, (caddr_t)dp, (unsigned)optlen); dp += optlen; } } for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) *dp++ = IPOPT_EOL; return (optlen); } /* * IP socket option processing. */ int ip_ctloutput(op, so, level, optname, mp) int op; struct socket *so; int level, optname; struct mbuf **mp; { register struct inpcb *inp; register struct mbuf *m = *mp; register int optval; int error = 0, s; s = splnet(); if (level != IPPROTO_IP) { error = EINVAL; if (op == PRCO_SETOPT && *mp) (void) m_free(*mp); } else if ((inp = sotoinpcb(so)) == NULL) { error = ENOTCONN; if (op == PRCO_SETOPT && *mp) (void) m_free(*mp); } else switch (op) { case PRCO_SETOPT: switch (optname) { case IP_OPTIONS: #ifdef notyet case IP_RETOPTS: error = ip_pcbopts(optname, &inp->inp_options, m); #else error = ip_pcbopts(&inp->inp_options, m); #endif break; #ifdef MULTICAST case IP_MULTICAST_IF: #if defined(RSVP_ISI) && defined(MROUTING) case IP_MULTICAST_VIF: #endif /* RSVP_ISI */ case IP_MULTICAST_TTL: case IP_MULTICAST_LOOP: case IP_ADD_MEMBERSHIP: case IP_DROP_MEMBERSHIP: error = ip_setmoptions(optname, &inp->inp_moptions, m); break; #endif /* MULTICAST */ default: error = ENOPROTOOPT; break; } if (m) (void)m_free(m); break; case PRCO_GETOPT: switch (optname) { case IP_OPTIONS: *mp = m = m_get(M_WAIT, MT_SOOPTS); if (inp->inp_options) { m->m_off = inp->inp_options->m_off; m->m_len = inp->inp_options->m_len; bcopy(mtod(inp->inp_options, caddr_t), mtod(m, caddr_t), (unsigned)m->m_len); } else m->m_len = 0; break; #ifdef MULTICAST case IP_MULTICAST_IF: #if defined(RSVP_ISI) && defined(MROUTING) case IP_MULTICAST_VIF: #endif /* RSVP_ISI */ case IP_MULTICAST_TTL: case IP_MULTICAST_LOOP: case IP_ADD_MEMBERSHIP: case IP_DROP_MEMBERSHIP: error = ip_getmoptions(optname, inp->inp_moptions, mp); break; #endif /* MULTICAST */ default: error = ENOPROTOOPT; break; } break; } splx(s); return (error); } /* * Set up IP options in pcb for insertion in output packets. * Store in mbuf with pointer in pcbopt, adding pseudo-option * with destination address if source routed. */ int #ifdef notyet ip_pcbopts(optname, pcbopt, m) int optname; #else ip_pcbopts(pcbopt, m) #endif struct mbuf **pcbopt; register struct mbuf *m; { register cnt, optlen; register u_char *cp; u_char opt; /* turn off any old options */ if (*pcbopt) (void)m_free(*pcbopt); *pcbopt = 0; if (m == (struct mbuf *)0 || m->m_len == 0) { /* * Only turning off any previous options. */ if (m) (void)m_free(m); return (0); } #ifndef vax if (m->m_len % sizeof(long)) goto bad; #endif /* * IP first-hop destination address will be stored before * actual options; move other options back * and clear it when none present. */ #if MAX_IPOPTLEN >= MMAXOFF - MMINOFF if (m->m_off + m->m_len + sizeof(struct in_addr) > MAX_IPOPTLEN) goto bad; #else if (m->m_off + m->m_len + sizeof(struct in_addr) > MMAXOFF) goto bad; #endif cnt = m->m_len; m->m_len += sizeof(struct in_addr); cp = mtod(m, u_char *) + sizeof(struct in_addr); ovbcopy(mtod(m, caddr_t), (caddr_t)cp, (unsigned)cnt); bzero(mtod(m, caddr_t), sizeof(struct in_addr)); for (; cnt > 0; cnt -= optlen, cp += optlen) { opt = cp[IPOPT_OPTVAL]; if (opt == IPOPT_EOL) break; if (opt == IPOPT_NOP) optlen = 1; else { optlen = cp[IPOPT_OLEN]; if (optlen <= IPOPT_OLEN || optlen > cnt) goto bad; } switch (opt) { default: break; case IPOPT_LSRR: case IPOPT_SSRR: /* * user process specifies route as: * ->A->B->C->D * D must be our final destination (but we can't * check that since we may not have connected yet). * A is first hop destination, which doesn't appear in * actual IP option, but is stored before the options. */ if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) goto bad; m->m_len -= sizeof(struct in_addr); cnt -= sizeof(struct in_addr); optlen -= sizeof(struct in_addr); cp[IPOPT_OLEN] = optlen; /* * Move first hop before start of options. */ bcopy((caddr_t)&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), sizeof(struct in_addr)); /* * Then copy rest of options back * to close up the deleted entry. */ ovbcopy((caddr_t)(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr)), (caddr_t)&cp[IPOPT_OFFSET+1], (unsigned)cnt + sizeof(struct in_addr)); break; } } if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) goto bad; *pcbopt = m; return (0); bad: (void)m_free(m); return (EINVAL); } #ifdef MULTICAST /* * Set the IP multicast options in response to user setsockopt(). */ ip_setmoptions(optname, mopts, m) int optname; struct mbuf **mopts; struct mbuf *m; { int error = 0; struct ip_moptions *imo; u_char loop; int i; struct in_addr addr; struct ip_mreq *mreq; struct ifnet *ifp; struct route ro; struct sockaddr_in *dst; if (*mopts == NULL) { /* * No multicast option buffer attached to the pcb; * allocate one and initialize to default values. */ MGET(*mopts, M_WAIT, MT_IPMOPTS); if (*mopts == NULL) return (ENOBUFS); imo = mtod(*mopts, struct ip_moptions *); imo->imo_multicast_ifp = NULL; #ifdef RSVP_ISI imo->imo_multicast_vif = -1; #endif /* RSVP_ISI */ imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; imo->imo_num_memberships = 0; } imo = mtod(*mopts, struct ip_moptions *); switch (optname) { #if defined(RSVP_ISI) && defined(MROUTING) /* store an index number for the vif you wanna use in the send */ case IP_MULTICAST_VIF: if (m == NULL || m->m_len != sizeof(int)) { error = EINVAL; break; } i = *(mtod(m, int *)); if (!legal_vif_num(i) && (i != -1)) { error = EINVAL; break; } imo->imo_multicast_vif = i; break; #endif /* RSVP_ISI && MROUTING */ case IP_MULTICAST_IF: /* * Select the interface for outgoing multicast packets. */ if (m == NULL || m->m_len != sizeof(struct in_addr)) { error = EINVAL; break; } addr = *(mtod(m, struct in_addr *)); /* * INADDR_ANY is used to remove a previous selection. * When no interface is selected, a default one is * chosen every time a multicast packet is sent. */ if (addr.s_addr == INADDR_ANY) { imo->imo_multicast_ifp = NULL; break; } /* * The selected interface is identified by its local * IP address. Find the interface and confirm that * it supports multicasting. */ INADDR_TO_IFP(addr, ifp); if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { error = EADDRNOTAVAIL; break; } imo->imo_multicast_ifp = ifp; break; case IP_MULTICAST_TTL: /* * Set the IP time-to-live for outgoing multicast packets. */ if (m == NULL || m->m_len != 1) { error = EINVAL; break; } imo->imo_multicast_ttl = *(mtod(m, u_char *)); break; case IP_MULTICAST_LOOP: /* * Set the loopback flag for outgoing multicast packets. * Must be zero or one. */ if (m == NULL || m->m_len != 1 || (loop = *(mtod(m, u_char *))) > 1) { error = EINVAL; break; } imo->imo_multicast_loop = loop; break; case IP_ADD_MEMBERSHIP: /* * Add a multicast group membership. * Group must be a valid IP multicast address. */ if (m == NULL || m->m_len != sizeof(struct ip_mreq)) { error = EINVAL; break; } mreq = mtod(m, struct ip_mreq *); if (!IN_MULTICAST(ntohl(mreq->imr_multiaddr.s_addr))) { error = EINVAL; break; } /* * If no interface address was provided, use the interface of * the route to the given multicast address. */ if (mreq->imr_interface.s_addr == INADDR_ANY) { bzero((caddr_t)&ro, sizeof(ro)); dst = (struct sockaddr_in *)&ro.ro_dst; dst->sin_family = AF_INET; dst->sin_addr = mreq->imr_multiaddr; rtalloc(&ro); if (ro.ro_rt == NULL) { error = EADDRNOTAVAIL; break; } ifp = ro.ro_rt->rt_ifp; rtfree(ro.ro_rt); } else { INADDR_TO_IFP(mreq->imr_interface, ifp); } /* * See if we found an interface, and confirm that it * supports multicast. */ if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { error = EADDRNOTAVAIL; break; } /* * See if the membership already exists or if all the * membership slots are full. */ for (i = 0; i < imo->imo_num_memberships; ++i) { if (imo->imo_membership[i]->inm_ifp == ifp && imo->imo_membership[i]->inm_addr.s_addr == mreq->imr_multiaddr.s_addr) break; } if (i < imo->imo_num_memberships) { error = EADDRINUSE; break; } if (i == IP_MAX_MEMBERSHIPS) { error = ETOOMANYREFS; break; } /* * Everything looks good; add a new record to the multicast * address list for the given interface. */ if ((imo->imo_membership[i] = in_addmulti(mreq->imr_multiaddr, ifp)) == NULL) { error = ENOBUFS; break; } ++imo->imo_num_memberships; break; case IP_DROP_MEMBERSHIP: /* * Drop a multicast group membership. * Group must be a valid IP multicast address. */ if (m == NULL || m->m_len != sizeof(struct ip_mreq)) { error = EINVAL; break; } mreq = mtod(m, struct ip_mreq *); if (!IN_MULTICAST(ntohl(mreq->imr_multiaddr.s_addr))) { error = EINVAL; break; } /* * If an interface address was specified, get a pointer * to its ifnet structure. */ if (mreq->imr_interface.s_addr == INADDR_ANY) ifp = NULL; else { INADDR_TO_IFP(mreq->imr_interface, ifp); if (ifp == NULL) { error = EADDRNOTAVAIL; break; } } /* * Find the membership in the membership array. */ for (i = 0; i < imo->imo_num_memberships; ++i) { if ((ifp == NULL || imo->imo_membership[i]->inm_ifp == ifp) && imo->imo_membership[i]->inm_addr.s_addr == mreq->imr_multiaddr.s_addr) break; } if (i == imo->imo_num_memberships) { error = EADDRNOTAVAIL; break; } /* * Give up the multicast address record to which the * membership points. */ in_delmulti(imo->imo_membership[i]); /* * Remove the gap in the membership array. */ for (++i; i < imo->imo_num_memberships; ++i) imo->imo_membership[i-1] = imo->imo_membership[i]; --imo->imo_num_memberships; break; default: error = EOPNOTSUPP; break; } /* * If all options have default values, no need to keep the mbuf. */ if (imo->imo_multicast_ifp == NULL && #ifdef RSVP_ISI imo->imo_multicast_vif == -1 && #endif /* RSVP_ISI */ imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && imo->imo_num_memberships == 0) { m_free(*mopts); *mopts = NULL; } return(error); } /* * Return the IP multicast options in response to user getsockopt(). */ ip_getmoptions(optname, mopts, m) int optname; struct mbuf *mopts; struct mbuf **m; { u_char *ttl; u_char *loop; struct in_addr *addr; struct ip_moptions *imo; struct in_ifaddr *ia; *m = m_get(M_WAIT, MT_IPMOPTS); imo = (mopts == NULL) ? NULL : mtod(mopts, struct ip_moptions *); switch (optname) { #if defined(RSVP_ISI) && defined(MROUTING) case IP_MULTICAST_VIF: if (imo!=NULL) *(mtod(*m, int *)) = imo->imo_multicast_vif; else *(mtod(*m, int *)) = -1; (*m)->m_len = sizeof(int); return(0); #endif /* RSVP_ISI && MROUTING */ case IP_MULTICAST_IF: addr = mtod(*m, struct in_addr *); (*m)->m_len = sizeof(struct in_addr); if (imo == NULL || imo->imo_multicast_ifp == NULL) addr->s_addr = INADDR_ANY; else { IFP_TO_IA(imo->imo_multicast_ifp, ia); addr->s_addr = (ia == NULL) ? INADDR_ANY : IA_SIN(ia)->sin_addr.s_addr; } return(0); case IP_MULTICAST_TTL: ttl = mtod(*m, u_char *); (*m)->m_len = 1; *ttl = (imo == NULL) ? IP_DEFAULT_MULTICAST_TTL : imo->imo_multicast_ttl; return(0); case IP_MULTICAST_LOOP: loop = mtod(*m, u_char *); (*m)->m_len = 1; *loop = (imo == NULL) ? IP_DEFAULT_MULTICAST_LOOP : imo->imo_multicast_loop; return(0); default: return(EOPNOTSUPP); } } /* * Discard the IP multicast options. */ ip_freemoptions(mopts) struct mbuf *mopts; { struct ip_moptions *imo; int i; if (mopts != NULL) { imo = mtod(mopts, struct ip_moptions *); for (i = 0; i < imo->imo_num_memberships; ++i) in_delmulti(imo->imo_membership[i]); m_free(mopts); } } /* * Routine called from ip_output() to loop back a copy of an IP multicast * packet to the input queue of a specified interface. Note that this * calls the output routine of the loopback "driver", but with an interface * pointer that might NOT be &loif -- easier than replicating that code here. */ ip_mloopback(ifp, m, dst) struct ifnet *ifp; register struct mbuf *m; register struct sockaddr_in *dst; { register struct ip *ip; struct mbuf *copym; copym = m_copy(m, 0, M_COPYALL); if (copym != NULL) { /* * We don't bother to fragment if the IP length is greater * than the interface's MTU. Can this possibly matter? */ ip = mtod(copym, struct ip *); #ifndef sparc ip->ip_len = htons((u_short)ip->ip_len); ip->ip_off = htons((u_short)ip->ip_off); #endif ip->ip_sum = 0; ip->ip_sum = in_cksum(copym, ip->ip_hl << 2); (void) looutput(ifp, copym, (struct sockaddr *)dst); } } #endif /* MULTICAST */