/* * Copyright (c) 1982, 1986, 1988, 1990, 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. * 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. * * @(#)ip_output.c 8.3 (Berkeley) 1/21/94 * $FreeBSD$ */ #include "opt_ipfw.h" #include "opt_ipsec.h" #include "opt_mac.h" #include "opt_mbuf_stress_test.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options"); #ifdef IPSEC #include #include #ifdef IPSEC_DEBUG #include #else #define KEYDEBUG(lev,arg) #endif #endif /*IPSEC*/ #ifdef FAST_IPSEC #include #include #include #endif /*FAST_IPSEC*/ #define print_ip(x, a, y) printf("%s %d.%d.%d.%d%s",\ x, (ntohl(a.s_addr)>>24)&0xFF,\ (ntohl(a.s_addr)>>16)&0xFF,\ (ntohl(a.s_addr)>>8)&0xFF,\ (ntohl(a.s_addr))&0xFF, y); u_short ip_id; #ifdef MBUF_STRESS_TEST int mbuf_frag_size = 0; SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW, &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size"); #endif static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *); static struct ifnet *ip_multicast_if(struct in_addr *, int *); static void ip_mloopback (struct ifnet *, struct mbuf *, struct sockaddr_in *, int); static int ip_getmoptions(struct inpcb *, struct sockopt *); static int ip_pcbopts(struct inpcb *, int, struct mbuf *); static int ip_setmoptions(struct inpcb *, struct sockopt *); int ip_optcopy(struct ip *, struct ip *); extern struct protosw inetsw[]; /* * 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. * In the IP forwarding case, the packet will arrive with options already * inserted, so must have a NULL opt pointer. */ int ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags, struct ip_moptions *imo, struct inpcb *inp) { struct ip *ip; struct ifnet *ifp = NULL; /* keep compiler happy */ struct mbuf *m0; int hlen = sizeof (struct ip); int len, error = 0; struct sockaddr_in *dst = NULL; /* keep compiler happy */ struct in_ifaddr *ia = NULL; int isbroadcast, sw_csum; struct route iproute; struct in_addr odst; #ifdef IPFIREWALL_FORWARD struct m_tag *fwd_tag = NULL; #endif #ifdef IPSEC struct secpolicy *sp = NULL; #endif #ifdef FAST_IPSEC struct secpolicy *sp = NULL; struct tdb_ident *tdbi; struct m_tag *mtag; int s; #endif /* FAST_IPSEC */ M_ASSERTPKTHDR(m); if (ro == NULL) { ro = &iproute; bzero(ro, sizeof (*ro)); } if (inp != NULL) INP_LOCK_ASSERT(inp); if (opt) { len = 0; m = ip_insertoptions(m, opt, &len); if (len != 0) hlen = len; } ip = mtod(m, struct ip *); /* * Fill in IP header. If we are not allowing fragmentation, * then the ip_id field is meaningless, but we don't set it * to zero. Doing so causes various problems when devices along * the path (routers, load balancers, firewalls, etc.) illegally * disable DF on our packet. Note that a 16-bit counter * will wrap around in less than 10 seconds at 100 Mbit/s on a * medium with MTU 1500. See Steven M. Bellovin, "A Technique * for Counting NATted Hosts", Proc. IMW'02, available at * . */ if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) { ip->ip_v = IPVERSION; ip->ip_hl = hlen >> 2; ip->ip_id = ip_newid(); ipstat.ips_localout++; } else { hlen = ip->ip_hl << 2; } dst = (struct sockaddr_in *)&ro->ro_dst; again: /* * 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. * The address family should also be checked in case of sharing the * cache with IPv6. */ if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 || dst->sin_family != AF_INET || dst->sin_addr.s_addr != ip->ip_dst.s_addr)) { RTFREE(ro->ro_rt); ro->ro_rt = (struct rtentry *)0; } #ifdef IPFIREWALL_FORWARD if (ro->ro_rt == NULL && fwd_tag == NULL) { #else if (ro->ro_rt == NULL) { #endif bzero(dst, sizeof(*dst)); dst->sin_family = AF_INET; dst->sin_len = sizeof(*dst); dst->sin_addr = ip->ip_dst; } /* * If routing to interface only, * short circuit routing lookup. */ if (flags & IP_ROUTETOIF) { if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL && (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) { ipstat.ips_noroute++; error = ENETUNREACH; goto bad; } ifp = ia->ia_ifp; ip->ip_ttl = 1; isbroadcast = in_broadcast(dst->sin_addr, ifp); } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) && imo != NULL && imo->imo_multicast_ifp != NULL) { /* * Bypass the normal routing lookup for multicast * packets if the interface is specified. */ ifp = imo->imo_multicast_ifp; IFP_TO_IA(ifp, ia); isbroadcast = 0; /* fool gcc */ } else { /* * We want to do any cloning requested by the link layer, * as this is probably required in all cases for correct * operation (as it is for ARP). */ if (ro->ro_rt == NULL) rtalloc_ign(ro, 0); if (ro->ro_rt == NULL) { ipstat.ips_noroute++; error = EHOSTUNREACH; goto bad; } ia = ifatoia(ro->ro_rt->rt_ifa); ifp = ro->ro_rt->rt_ifp; ro->ro_rt->rt_rmx.rmx_pksent++; if (ro->ro_rt->rt_flags & RTF_GATEWAY) dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway; if (ro->ro_rt->rt_flags & RTF_HOST) isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST); else isbroadcast = in_broadcast(dst->sin_addr, ifp); } if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { struct in_multi *inm; m->m_flags |= M_MCAST; /* * 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 (imo != NULL) { ip->ip_ttl = imo->imo_multicast_ttl; if (imo->imo_multicast_vif != -1) ip->ip_src.s_addr = ip_mcast_src ? ip_mcast_src(imo->imo_multicast_vif) : INADDR_ANY; } else ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; /* * Confirm that the outgoing interface supports multicast. */ if ((imo == NULL) || (imo->imo_multicast_vif == -1)) { if ((ifp->if_flags & IFF_MULTICAST) == 0) { ipstat.ips_noroute++; error = ENETUNREACH; goto bad; } } /* * If source address not specified yet, use address * of outgoing interface. */ if (ip->ip_src.s_addr == INADDR_ANY) { /* Interface may have no addresses. */ if (ia != NULL) ip->ip_src = IA_SIN(ia)->sin_addr; } 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, hlen); } else { /* * 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. */ if (ip_mrouter && (flags & IP_FORWARDING) == 0) { /* * If rsvp daemon is not running, do not * 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_mforward(ip, ifp, m, imo) != 0) { m_freem(m); goto done; } } } /* * 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->if_flags & IFF_LOOPBACK) { m_freem(m); goto done; } goto sendit; } #ifndef notdef /* * If the source address is not specified yet, use the address * of the outoing interface. */ if (ip->ip_src.s_addr == INADDR_ANY) { /* Interface may have no addresses. */ if (ia != NULL) { ip->ip_src = IA_SIN(ia)->sin_addr; } } #endif /* notdef */ /* * Verify that we have any chance at all of being able to queue the * packet or packet fragments, unless ALTQ is enabled on the given * interface in which case packetdrop should be done by queueing. */ #ifdef ALTQ if ((!ALTQ_IS_ENABLED(&ifp->if_snd)) && ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >= ifp->if_snd.ifq_maxlen)) #else if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >= ifp->if_snd.ifq_maxlen) #endif /* ALTQ */ { error = ENOBUFS; ipstat.ips_odropped++; goto bad; } /* * Look for broadcast address and * verify user is allowed to send * such a packet. */ if (isbroadcast) { if ((ifp->if_flags & IFF_BROADCAST) == 0) { error = EADDRNOTAVAIL; goto bad; } if ((flags & IP_ALLOWBROADCAST) == 0) { error = EACCES; goto bad; } /* don't allow broadcast messages to be fragmented */ if (ip->ip_len > ifp->if_mtu) { error = EMSGSIZE; goto bad; } if (flags & IP_SENDONES) ip->ip_dst.s_addr = INADDR_BROADCAST; m->m_flags |= M_BCAST; } else { m->m_flags &= ~M_BCAST; } sendit: #ifdef IPSEC /* get SP for this packet */ if (inp == NULL) sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error); else sp = ipsec4_getpolicybypcb(m, IPSEC_DIR_OUTBOUND, inp, &error); if (sp == NULL) { ipsecstat.out_inval++; goto bad; } error = 0; /* check policy */ switch (sp->policy) { case IPSEC_POLICY_DISCARD: /* * This packet is just discarded. */ ipsecstat.out_polvio++; goto bad; case IPSEC_POLICY_BYPASS: case IPSEC_POLICY_NONE: case IPSEC_POLICY_TCP: /* no need to do IPsec. */ goto skip_ipsec; case IPSEC_POLICY_IPSEC: if (sp->req == NULL) { /* acquire a policy */ error = key_spdacquire(sp); goto bad; } break; case IPSEC_POLICY_ENTRUST: default: printf("ip_output: Invalid policy found. %d\n", sp->policy); } { struct ipsec_output_state state; bzero(&state, sizeof(state)); state.m = m; if (flags & IP_ROUTETOIF) { state.ro = &iproute; bzero(&iproute, sizeof(iproute)); } else state.ro = ro; state.dst = (struct sockaddr *)dst; ip->ip_sum = 0; /* * XXX * delayed checksums are not currently compatible with IPsec */ if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { in_delayed_cksum(m); m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; } ip->ip_len = htons(ip->ip_len); ip->ip_off = htons(ip->ip_off); error = ipsec4_output(&state, sp, flags); m = state.m; if (flags & IP_ROUTETOIF) { /* * if we have tunnel mode SA, we may need to ignore * IP_ROUTETOIF. */ if (state.ro != &iproute || state.ro->ro_rt != NULL) { flags &= ~IP_ROUTETOIF; ro = state.ro; } } else ro = state.ro; dst = (struct sockaddr_in *)state.dst; if (error) { /* mbuf is already reclaimed in ipsec4_output. */ m = NULL; switch (error) { case EHOSTUNREACH: case ENETUNREACH: case EMSGSIZE: case ENOBUFS: case ENOMEM: break; default: printf("ip4_output (ipsec): error code %d\n", error); /*fall through*/ case ENOENT: /* don't show these error codes to the user */ error = 0; break; } goto bad; } /* be sure to update variables that are affected by ipsec4_output() */ ip = mtod(m, struct ip *); hlen = ip->ip_hl << 2; if (ro->ro_rt == NULL) { if ((flags & IP_ROUTETOIF) == 0) { printf("ip_output: " "can't update route after IPsec processing\n"); error = EHOSTUNREACH; /*XXX*/ goto bad; } } else { if (state.encap) { ia = ifatoia(ro->ro_rt->rt_ifa); ifp = ro->ro_rt->rt_ifp; } } } /* make it flipped, again. */ ip->ip_len = ntohs(ip->ip_len); ip->ip_off = ntohs(ip->ip_off); skip_ipsec: #endif /*IPSEC*/ #ifdef FAST_IPSEC /* * Check the security policy (SP) for the packet and, if * required, do IPsec-related processing. There are two * cases here; the first time a packet is sent through * it will be untagged and handled by ipsec4_checkpolicy. * If the packet is resubmitted to ip_output (e.g. after * AH, ESP, etc. processing), there will be a tag to bypass * the lookup and related policy checking. */ mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); s = splnet(); if (mtag != NULL) { tdbi = (struct tdb_ident *)(mtag + 1); sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND); if (sp == NULL) error = -EINVAL; /* force silent drop */ m_tag_delete(m, mtag); } else { sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, inp); } /* * There are four return cases: * sp != NULL apply IPsec policy * sp == NULL, error == 0 no IPsec handling needed * sp == NULL, error == -EINVAL discard packet w/o error * sp == NULL, error != 0 discard packet, report error */ if (sp != NULL) { /* Loop detection, check if ipsec processing already done */ KASSERT(sp->req != NULL, ("ip_output: no ipsec request")); for (mtag = m_tag_first(m); mtag != NULL; mtag = m_tag_next(m, mtag)) { if (mtag->m_tag_cookie != MTAG_ABI_COMPAT) continue; if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE && mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED) continue; /* * Check if policy has an SA associated with it. * This can happen when an SP has yet to acquire * an SA; e.g. on first reference. If it occurs, * then we let ipsec4_process_packet do its thing. */ if (sp->req->sav == NULL) break; tdbi = (struct tdb_ident *)(mtag + 1); if (tdbi->spi == sp->req->sav->spi && tdbi->proto == sp->req->sav->sah->saidx.proto && bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst, sizeof (union sockaddr_union)) == 0) { /* * No IPsec processing is needed, free * reference to SP. * * NB: null pointer to avoid free at * done: below. */ KEY_FREESP(&sp), sp = NULL; splx(s); goto spd_done; } } /* * Do delayed checksums now because we send before * this is done in the normal processing path. */ if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { in_delayed_cksum(m); m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; } ip->ip_len = htons(ip->ip_len); ip->ip_off = htons(ip->ip_off); /* NB: callee frees mbuf */ error = ipsec4_process_packet(m, sp->req, flags, 0); /* * Preserve KAME behaviour: ENOENT can be returned * when an SA acquire is in progress. Don't propagate * this to user-level; it confuses applications. * * XXX this will go away when the SADB is redone. */ if (error == ENOENT) error = 0; splx(s); goto done; } else { splx(s); if (error != 0) { /* * Hack: -EINVAL is used to signal that a packet * should be silently discarded. This is typically * because we asked key management for an SA and * it was delayed (e.g. kicked up to IKE). */ if (error == -EINVAL) error = 0; goto bad; } else { /* No IPsec processing for this packet. */ } #ifdef notyet /* * If deferred crypto processing is needed, check that * the interface supports it. */ mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL); if (mtag != NULL && (ifp->if_capenable & IFCAP_IPSEC) == 0) { /* notify IPsec to do its own crypto */ ipsp_skipcrypto_unmark((struct tdb_ident *)(mtag + 1)); error = EHOSTUNREACH; goto bad; } #endif } spd_done: #endif /* FAST_IPSEC */ /* Jump over all PFIL processing if hooks are not active. */ if (inet_pfil_hook.ph_busy_count == -1) goto passout; /* Run through list of hooks for output packets. */ odst.s_addr = ip->ip_dst.s_addr; error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT, inp); if (error != 0 || m == NULL) goto done; ip = mtod(m, struct ip *); /* See if destination IP address was changed by packet filter. */ if (odst.s_addr != ip->ip_dst.s_addr) { m->m_flags |= M_SKIP_FIREWALL; /* If destination is now ourself drop to ip_input(). */ if (in_localip(ip->ip_dst)) { m->m_flags |= M_FASTFWD_OURS; if (m->m_pkthdr.rcvif == NULL) m->m_pkthdr.rcvif = loif; if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { m->m_pkthdr.csum_flags |= CSUM_DATA_VALID | CSUM_PSEUDO_HDR; m->m_pkthdr.csum_data = 0xffff; } m->m_pkthdr.csum_flags |= CSUM_IP_CHECKED | CSUM_IP_VALID; error = netisr_queue(NETISR_IP, m); goto done; } else goto again; /* Redo the routing table lookup. */ } #ifdef IPFIREWALL_FORWARD /* See if local, if yes, send it to netisr with IP_FASTFWD_OURS. */ if (m->m_flags & M_FASTFWD_OURS) { if (m->m_pkthdr.rcvif == NULL) m->m_pkthdr.rcvif = loif; if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { m->m_pkthdr.csum_flags |= CSUM_DATA_VALID | CSUM_PSEUDO_HDR; m->m_pkthdr.csum_data = 0xffff; } m->m_pkthdr.csum_flags |= CSUM_IP_CHECKED | CSUM_IP_VALID; error = netisr_queue(NETISR_IP, m); goto done; } /* Or forward to some other address? */ fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); if (fwd_tag) { if (!in_localip(ip->ip_src) && !in_localaddr(ip->ip_dst)) { dst = (struct sockaddr_in *)&ro->ro_dst; bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in)); m->m_flags |= M_SKIP_FIREWALL; m_tag_delete(m, fwd_tag); goto again; } else { m_tag_delete(m, fwd_tag); /* Continue. */ } } #endif passout: /* 127/8 must not appear on wire - RFC1122. */ if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { if ((ifp->if_flags & IFF_LOOPBACK) == 0) { ipstat.ips_badaddr++; error = EADDRNOTAVAIL; goto bad; } } m->m_pkthdr.csum_flags |= CSUM_IP; sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist; if (sw_csum & CSUM_DELAY_DATA) { in_delayed_cksum(m); sw_csum &= ~CSUM_DELAY_DATA; } m->m_pkthdr.csum_flags &= ifp->if_hwassist; /* * If small enough for interface, or the interface will take * care of the fragmentation for us, can just send directly. */ if (ip->ip_len <= ifp->if_mtu || (ifp->if_hwassist & CSUM_FRAGMENT && ((ip->ip_off & IP_DF) == 0))) { ip->ip_len = htons(ip->ip_len); ip->ip_off = htons(ip->ip_off); ip->ip_sum = 0; if (sw_csum & CSUM_DELAY_IP) ip->ip_sum = in_cksum(m, hlen); /* Record statistics for this interface address. */ if (!(flags & IP_FORWARDING) && ia) { ia->ia_ifa.if_opackets++; ia->ia_ifa.if_obytes += m->m_pkthdr.len; } #ifdef IPSEC /* clean ipsec history once it goes out of the node */ ipsec_delaux(m); #endif #ifdef MBUF_STRESS_TEST if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) m = m_fragment(m, M_DONTWAIT, mbuf_frag_size); #endif error = (*ifp->if_output)(ifp, m, (struct sockaddr *)dst, ro->ro_rt); goto done; } if (ip->ip_off & IP_DF) { error = EMSGSIZE; /* * This case can happen if the user changed the MTU * of an interface after enabling IP on it. Because * most netifs don't keep track of routes pointing to * them, there is no way for one to update all its * routes when the MTU is changed. */ if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) && (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) { ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu; } ipstat.ips_cantfrag++; goto bad; } /* * Too large for interface; fragment if possible. If successful, * on return, m will point to a list of packets to be sent. */ error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum); if (error) goto bad; for (; m; m = m0) { m0 = m->m_nextpkt; m->m_nextpkt = 0; #ifdef IPSEC /* clean ipsec history once it goes out of the node */ ipsec_delaux(m); #endif if (error == 0) { /* Record statistics for this interface address. */ if (ia != NULL) { ia->ia_ifa.if_opackets++; ia->ia_ifa.if_obytes += m->m_pkthdr.len; } error = (*ifp->if_output)(ifp, m, (struct sockaddr *)dst, ro->ro_rt); } else m_freem(m); } if (error == 0) ipstat.ips_fragmented++; done: if (ro == &iproute && ro->ro_rt) { RTFREE(ro->ro_rt); } #ifdef IPSEC if (sp != NULL) { KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP ip_output call free SP:%p\n", sp)); key_freesp(sp); } #endif #ifdef FAST_IPSEC if (sp != NULL) KEY_FREESP(&sp); #endif return (error); bad: m_freem(m); goto done; } /* * Create a chain of fragments which fit the given mtu. m_frag points to the * mbuf to be fragmented; on return it points to the chain with the fragments. * Return 0 if no error. If error, m_frag may contain a partially built * chain of fragments that should be freed by the caller. * * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist) * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP). */ int ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu, u_long if_hwassist_flags, int sw_csum) { int error = 0; int hlen = ip->ip_hl << 2; int len = (mtu - hlen) & ~7; /* size of payload in each fragment */ int off; struct mbuf *m0 = *m_frag; /* the original packet */ int firstlen; struct mbuf **mnext; int nfrags; if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */ ipstat.ips_cantfrag++; return EMSGSIZE; } /* * Must be able to put at least 8 bytes per fragment. */ if (len < 8) return EMSGSIZE; /* * If the interface will not calculate checksums on * fragmented packets, then do it here. */ if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA && (if_hwassist_flags & CSUM_IP_FRAGS) == 0) { in_delayed_cksum(m0); m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; } if (len > PAGE_SIZE) { /* * Fragment large datagrams such that each segment * contains a multiple of PAGE_SIZE amount of data, * plus headers. This enables a receiver to perform * page-flipping zero-copy optimizations. * * XXX When does this help given that sender and receiver * could have different page sizes, and also mtu could * be less than the receiver's page size ? */ int newlen; struct mbuf *m; for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next) off += m->m_len; /* * firstlen (off - hlen) must be aligned on an * 8-byte boundary */ if (off < hlen) goto smart_frag_failure; off = ((off - hlen) & ~7) + hlen; newlen = (~PAGE_MASK) & mtu; if ((newlen + sizeof (struct ip)) > mtu) { /* we failed, go back the default */ smart_frag_failure: newlen = len; off = hlen + len; } len = newlen; } else { off = hlen + len; } firstlen = off - hlen; mnext = &m0->m_nextpkt; /* pointer to next packet */ /* * Loop through length of segment after first fragment, * make new header and copy data of each part and link onto chain. * Here, m0 is the original packet, m is the fragment being created. * The fragments are linked off the m_nextpkt of the original * packet, which after processing serves as the first fragment. */ for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) { struct ip *mhip; /* ip header on the fragment */ struct mbuf *m; int mhlen = sizeof (struct ip); MGETHDR(m, M_DONTWAIT, MT_HEADER); if (m == NULL) { error = ENOBUFS; ipstat.ips_odropped++; goto done; } m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG; /* * In the first mbuf, leave room for the link header, then * copy the original IP header including options. The payload * goes into an additional mbuf chain returned by m_copy(). */ m->m_data += max_linkhdr; mhip = mtod(m, struct ip *); *mhip = *ip; if (hlen > sizeof (struct ip)) { mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip); mhip->ip_v = IPVERSION; mhip->ip_hl = mhlen >> 2; } m->m_len = mhlen; /* XXX do we need to add ip->ip_off below ? */ mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off; if (off + len >= ip->ip_len) { /* last fragment */ len = ip->ip_len - off; m->m_flags |= M_LASTFRAG; } 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 == NULL) { /* copy failed */ m_free(m); error = ENOBUFS; /* ??? */ ipstat.ips_odropped++; goto done; } m->m_pkthdr.len = mhlen + len; m->m_pkthdr.rcvif = (struct ifnet *)0; #ifdef MAC mac_create_fragment(m0, m); #endif m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags; mhip->ip_off = htons(mhip->ip_off); mhip->ip_sum = 0; if (sw_csum & CSUM_DELAY_IP) mhip->ip_sum = in_cksum(m, mhlen); *mnext = m; mnext = &m->m_nextpkt; } ipstat.ips_ofragments += nfrags; /* set first marker for fragment chain */ m0->m_flags |= M_FIRSTFRAG | M_FRAG; m0->m_pkthdr.csum_data = nfrags; /* * Update first fragment by trimming what's been copied out * and updating header. */ m_adj(m0, hlen + firstlen - ip->ip_len); m0->m_pkthdr.len = hlen + firstlen; ip->ip_len = htons((u_short)m0->m_pkthdr.len); ip->ip_off |= IP_MF; ip->ip_off = htons(ip->ip_off); ip->ip_sum = 0; if (sw_csum & CSUM_DELAY_IP) ip->ip_sum = in_cksum(m0, hlen); done: *m_frag = m0; return error; } void in_delayed_cksum(struct mbuf *m) { struct ip *ip; u_short csum, offset; ip = mtod(m, struct ip *); offset = ip->ip_hl << 2 ; csum = in_cksum_skip(m, ip->ip_len, offset); if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0) csum = 0xffff; offset += m->m_pkthdr.csum_data; /* checksum offset */ if (offset + sizeof(u_short) > m->m_len) { printf("delayed m_pullup, m->len: %d off: %d p: %d\n", m->m_len, offset, ip->ip_p); /* * XXX * this shouldn't happen, but if it does, the * correct behavior may be to insert the checksum * in the existing chain instead of rearranging it. */ m = m_pullup(m, offset + sizeof(u_short)); } *(u_short *)(m->m_data + offset) = csum; } /* * 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. * * XXX This routine assumes that the packet has no options in place. */ 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 (optlen + ip->ip_len > IP_MAXPACKET) { *phlen = 0; return (m); /* XXX should fail */ } if (p->ipopt_dst.s_addr) ip->ip_dst = p->ipopt_dst; if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) { MGETHDR(n, M_DONTWAIT, MT_HEADER); if (n == NULL) { *phlen = 0; return (m); } n->m_pkthdr.rcvif = (struct ifnet *)0; #ifdef MAC mac_create_mbuf_from_mbuf(m, n); #endif n->m_pkthdr.len = m->m_pkthdr.len + optlen; m->m_len -= sizeof(struct ip); m->m_data += sizeof(struct ip); n->m_next = m; m = n; m->m_len = optlen + sizeof(struct ip); m->m_data += max_linkhdr; bcopy(ip, mtod(m, void *), sizeof(struct ip)); } else { m->m_data -= optlen; m->m_len += optlen; m->m_pkthdr.len += optlen; bcopy(ip, mtod(m, void *), sizeof(struct ip)); } ip = mtod(m, struct ip *); bcopy(p->ipopt_list, ip + 1, optlen); *phlen = sizeof(struct ip) + optlen; ip->ip_v = IPVERSION; ip->ip_hl = *phlen >> 2; 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; } KASSERT(cnt >= IPOPT_OLEN + sizeof(*cp), ("ip_optcopy: malformed ipv4 option")); optlen = cp[IPOPT_OLEN]; KASSERT(optlen >= IPOPT_OLEN + sizeof(*cp) && optlen <= cnt, ("ip_optcopy: malformed ipv4 option")); /* bogus lengths should have been caught by ip_dooptions */ if (optlen > cnt) optlen = cnt; if (IPOPT_COPIED(opt)) { bcopy(cp, dp, 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(so, sopt) struct socket *so; struct sockopt *sopt; { struct inpcb *inp = sotoinpcb(so); int error, optval; error = optval = 0; if (sopt->sopt_level != IPPROTO_IP) { return (EINVAL); } switch (sopt->sopt_dir) { case SOPT_SET: switch (sopt->sopt_name) { case IP_OPTIONS: #ifdef notyet case IP_RETOPTS: #endif { struct mbuf *m; if (sopt->sopt_valsize > MLEN) { error = EMSGSIZE; break; } MGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT, MT_HEADER); if (m == NULL) { error = ENOBUFS; break; } m->m_len = sopt->sopt_valsize; error = sooptcopyin(sopt, mtod(m, char *), m->m_len, m->m_len); INP_LOCK(inp); error = ip_pcbopts(inp, sopt->sopt_name, m); INP_UNLOCK(inp); return (error); } case IP_TOS: case IP_TTL: case IP_RECVOPTS: case IP_RECVRETOPTS: case IP_RECVDSTADDR: case IP_RECVTTL: case IP_RECVIF: case IP_FAITH: case IP_ONESBCAST: error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) break; switch (sopt->sopt_name) { case IP_TOS: inp->inp_ip_tos = optval; break; case IP_TTL: inp->inp_ip_ttl = optval; break; #define OPTSET(bit) do { \ INP_LOCK(inp); \ if (optval) \ inp->inp_flags |= bit; \ else \ inp->inp_flags &= ~bit; \ INP_UNLOCK(inp); \ } while (0) case IP_RECVOPTS: OPTSET(INP_RECVOPTS); break; case IP_RECVRETOPTS: OPTSET(INP_RECVRETOPTS); break; case IP_RECVDSTADDR: OPTSET(INP_RECVDSTADDR); break; case IP_RECVTTL: OPTSET(INP_RECVTTL); break; case IP_RECVIF: OPTSET(INP_RECVIF); break; case IP_FAITH: OPTSET(INP_FAITH); break; case IP_ONESBCAST: OPTSET(INP_ONESBCAST); break; } break; #undef OPTSET case IP_MULTICAST_IF: case IP_MULTICAST_VIF: case IP_MULTICAST_TTL: case IP_MULTICAST_LOOP: case IP_ADD_MEMBERSHIP: case IP_DROP_MEMBERSHIP: error = ip_setmoptions(inp, sopt); break; case IP_PORTRANGE: error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) break; INP_LOCK(inp); switch (optval) { case IP_PORTRANGE_DEFAULT: inp->inp_flags &= ~(INP_LOWPORT); inp->inp_flags &= ~(INP_HIGHPORT); break; case IP_PORTRANGE_HIGH: inp->inp_flags &= ~(INP_LOWPORT); inp->inp_flags |= INP_HIGHPORT; break; case IP_PORTRANGE_LOW: inp->inp_flags &= ~(INP_HIGHPORT); inp->inp_flags |= INP_LOWPORT; break; default: error = EINVAL; break; } INP_UNLOCK(inp); break; #if defined(IPSEC) || defined(FAST_IPSEC) case IP_IPSEC_POLICY: { caddr_t req; size_t len = 0; int priv; struct mbuf *m; int optname; if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */ break; if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */ break; priv = (sopt->sopt_td != NULL && suser(sopt->sopt_td) != 0) ? 0 : 1; req = mtod(m, caddr_t); len = m->m_len; optname = sopt->sopt_name; error = ipsec4_set_policy(inp, optname, req, len, priv); m_freem(m); break; } #endif /*IPSEC*/ default: error = ENOPROTOOPT; break; } break; case SOPT_GET: switch (sopt->sopt_name) { case IP_OPTIONS: case IP_RETOPTS: if (inp->inp_options) error = sooptcopyout(sopt, mtod(inp->inp_options, char *), inp->inp_options->m_len); else sopt->sopt_valsize = 0; break; case IP_TOS: case IP_TTL: case IP_RECVOPTS: case IP_RECVRETOPTS: case IP_RECVDSTADDR: case IP_RECVTTL: case IP_RECVIF: case IP_PORTRANGE: case IP_FAITH: case IP_ONESBCAST: switch (sopt->sopt_name) { case IP_TOS: optval = inp->inp_ip_tos; break; case IP_TTL: optval = inp->inp_ip_ttl; break; #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) case IP_RECVOPTS: optval = OPTBIT(INP_RECVOPTS); break; case IP_RECVRETOPTS: optval = OPTBIT(INP_RECVRETOPTS); break; case IP_RECVDSTADDR: optval = OPTBIT(INP_RECVDSTADDR); break; case IP_RECVTTL: optval = OPTBIT(INP_RECVTTL); break; case IP_RECVIF: optval = OPTBIT(INP_RECVIF); break; case IP_PORTRANGE: if (inp->inp_flags & INP_HIGHPORT) optval = IP_PORTRANGE_HIGH; else if (inp->inp_flags & INP_LOWPORT) optval = IP_PORTRANGE_LOW; else optval = 0; break; case IP_FAITH: optval = OPTBIT(INP_FAITH); break; case IP_ONESBCAST: optval = OPTBIT(INP_ONESBCAST); break; } error = sooptcopyout(sopt, &optval, sizeof optval); break; case IP_MULTICAST_IF: case IP_MULTICAST_VIF: case IP_MULTICAST_TTL: case IP_MULTICAST_LOOP: case IP_ADD_MEMBERSHIP: case IP_DROP_MEMBERSHIP: error = ip_getmoptions(inp, sopt); break; #if defined(IPSEC) || defined(FAST_IPSEC) case IP_IPSEC_POLICY: { struct mbuf *m = NULL; caddr_t req = NULL; size_t len = 0; if (m != 0) { req = mtod(m, caddr_t); len = m->m_len; } error = ipsec4_get_policy(sotoinpcb(so), req, len, &m); if (error == 0) error = soopt_mcopyout(sopt, m); /* XXX */ if (error == 0) m_freem(m); break; } #endif /*IPSEC*/ default: error = ENOPROTOOPT; break; } break; } 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. */ static int ip_pcbopts(struct inpcb *inp, int optname, struct mbuf *m) { register int cnt, optlen; register u_char *cp; struct mbuf **pcbopt; u_char opt; INP_LOCK_ASSERT(inp); pcbopt = &inp->inp_options; /* turn off any old options */ if (*pcbopt) (void)m_free(*pcbopt); *pcbopt = 0; if (m == NULL || m->m_len == 0) { /* * Only turning off any previous options. */ if (m != NULL) (void)m_free(m); return (0); } if (m->m_len % sizeof(int32_t)) goto bad; /* * IP first-hop destination address will be stored before * actual options; move other options back * and clear it when none present. */ if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) goto bad; cnt = m->m_len; m->m_len += sizeof(struct in_addr); cp = mtod(m, u_char *) + sizeof(struct in_addr); bcopy(mtod(m, void *), cp, (unsigned)cnt); bzero(mtod(m, void *), 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 { if (cnt < IPOPT_OLEN + sizeof(*cp)) goto bad; optlen = cp[IPOPT_OLEN]; if (optlen < IPOPT_OLEN + sizeof(*cp) || 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. */ bcopy((&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr)), &cp[IPOPT_OFFSET+1], (unsigned)cnt - (IPOPT_MINOFF - 1)); break; } } if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) goto bad; *pcbopt = m; return (0); bad: (void)m_free(m); return (EINVAL); } /* * XXX * The whole multicast option thing needs to be re-thought. * Several of these options are equally applicable to non-multicast * transmission, and one (IP_MULTICAST_TTL) totally duplicates a * standard option (IP_TTL). */ /* * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. */ static struct ifnet * ip_multicast_if(a, ifindexp) struct in_addr *a; int *ifindexp; { int ifindex; struct ifnet *ifp; if (ifindexp) *ifindexp = 0; if (ntohl(a->s_addr) >> 24 == 0) { ifindex = ntohl(a->s_addr) & 0xffffff; if (ifindex < 0 || if_index < ifindex) return NULL; ifp = ifnet_byindex(ifindex); if (ifindexp) *ifindexp = ifindex; } else { INADDR_TO_IFP(*a, ifp); } return ifp; } /* * Set the IP multicast options in response to user setsockopt(). */ static int ip_setmoptions(struct inpcb *inp, struct sockopt *sopt) { int error = 0; int i; struct in_addr addr; struct ip_mreq mreq; struct ifnet *ifp; struct ip_moptions *imo; struct route ro; struct sockaddr_in *dst; int ifindex; int s; imo = inp->inp_moptions; if (imo == NULL) { /* * No multicast option buffer attached to the pcb; * allocate one and initialize to default values. */ imo = (struct ip_moptions*)malloc(sizeof(*imo), M_IPMOPTS, M_WAITOK); if (imo == NULL) return (ENOBUFS); inp->inp_moptions = imo; imo->imo_multicast_ifp = NULL; imo->imo_multicast_addr.s_addr = INADDR_ANY; imo->imo_multicast_vif = -1; imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; imo->imo_num_memberships = 0; } switch (sopt->sopt_name) { /* store an index number for the vif you wanna use in the send */ case IP_MULTICAST_VIF: if (legal_vif_num == 0) { error = EOPNOTSUPP; break; } error = sooptcopyin(sopt, &i, sizeof i, sizeof i); if (error) break; if (!legal_vif_num(i) && (i != -1)) { error = EINVAL; break; } imo->imo_multicast_vif = i; break; case IP_MULTICAST_IF: /* * Select the interface for outgoing multicast packets. */ error = sooptcopyin(sopt, &addr, sizeof addr, sizeof addr); if (error) break; /* * 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. */ s = splimp(); ifp = ip_multicast_if(&addr, &ifindex); if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { splx(s); error = EADDRNOTAVAIL; break; } imo->imo_multicast_ifp = ifp; if (ifindex) imo->imo_multicast_addr = addr; else imo->imo_multicast_addr.s_addr = INADDR_ANY; splx(s); break; case IP_MULTICAST_TTL: /* * Set the IP time-to-live for outgoing multicast packets. * The original multicast API required a char argument, * which is inconsistent with the rest of the socket API. * We allow either a char or an int. */ if (sopt->sopt_valsize == 1) { u_char ttl; error = sooptcopyin(sopt, &ttl, 1, 1); if (error) break; imo->imo_multicast_ttl = ttl; } else { u_int ttl; error = sooptcopyin(sopt, &ttl, sizeof ttl, sizeof ttl); if (error) break; if (ttl > 255) error = EINVAL; else imo->imo_multicast_ttl = ttl; } break; case IP_MULTICAST_LOOP: /* * Set the loopback flag for outgoing multicast packets. * Must be zero or one. The original multicast API required a * char argument, which is inconsistent with the rest * of the socket API. We allow either a char or an int. */ if (sopt->sopt_valsize == 1) { u_char loop; error = sooptcopyin(sopt, &loop, 1, 1); if (error) break; imo->imo_multicast_loop = !!loop; } else { u_int loop; error = sooptcopyin(sopt, &loop, sizeof loop, sizeof loop); if (error) break; imo->imo_multicast_loop = !!loop; } break; case IP_ADD_MEMBERSHIP: /* * Add a multicast group membership. * Group must be a valid IP multicast address. */ error = sooptcopyin(sopt, &mreq, sizeof mreq, sizeof mreq); if (error) break; if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { error = EINVAL; break; } s = splimp(); /* * 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_len = sizeof(*dst); dst->sin_family = AF_INET; dst->sin_addr = mreq.imr_multiaddr; rtalloc_ign(&ro, RTF_CLONING); if (ro.ro_rt == NULL) { error = EADDRNOTAVAIL; splx(s); break; } ifp = ro.ro_rt->rt_ifp; RTFREE(ro.ro_rt); } else { ifp = ip_multicast_if(&mreq.imr_interface, NULL); } /* * See if we found an interface, and confirm that it * supports multicast. */ if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { error = EADDRNOTAVAIL; splx(s); 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; splx(s); break; } if (i == IP_MAX_MEMBERSHIPS) { error = ETOOMANYREFS; splx(s); 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; splx(s); break; } ++imo->imo_num_memberships; splx(s); break; case IP_DROP_MEMBERSHIP: /* * Drop a multicast group membership. * Group must be a valid IP multicast address. */ error = sooptcopyin(sopt, &mreq, sizeof mreq, sizeof mreq); if (error) break; if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { error = EINVAL; break; } s = splimp(); /* * If an interface address was specified, get a pointer * to its ifnet structure. */ if (mreq.imr_interface.s_addr == INADDR_ANY) ifp = NULL; else { ifp = ip_multicast_if(&mreq.imr_interface, NULL); if (ifp == NULL) { error = EADDRNOTAVAIL; splx(s); 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; splx(s); 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; splx(s); break; default: error = EOPNOTSUPP; break; } /* * If all options have default values, no need to keep the mbuf. */ if (imo->imo_multicast_ifp == NULL && imo->imo_multicast_vif == -1 && imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && imo->imo_num_memberships == 0) { free(inp->inp_moptions, M_IPMOPTS); inp->inp_moptions = NULL; } return (error); } /* * Return the IP multicast options in response to user getsockopt(). */ static int ip_getmoptions(struct inpcb *inp, struct sockopt *sopt) { struct ip_moptions *imo; struct in_addr addr; struct in_ifaddr *ia; int error, optval; u_char coptval; INP_LOCK(inp); imo = inp->inp_moptions; error = 0; switch (sopt->sopt_name) { case IP_MULTICAST_VIF: if (imo != NULL) optval = imo->imo_multicast_vif; else optval = -1; INP_UNLOCK(inp); error = sooptcopyout(sopt, &optval, sizeof optval); break; case IP_MULTICAST_IF: if (imo == NULL || imo->imo_multicast_ifp == NULL) addr.s_addr = INADDR_ANY; else if (imo->imo_multicast_addr.s_addr) { /* return the value user has set */ addr = imo->imo_multicast_addr; } else { IFP_TO_IA(imo->imo_multicast_ifp, ia); addr.s_addr = (ia == NULL) ? INADDR_ANY : IA_SIN(ia)->sin_addr.s_addr; } INP_UNLOCK(inp); error = sooptcopyout(sopt, &addr, sizeof addr); break; case IP_MULTICAST_TTL: if (imo == 0) optval = coptval = IP_DEFAULT_MULTICAST_TTL; else optval = coptval = imo->imo_multicast_ttl; INP_UNLOCK(inp); if (sopt->sopt_valsize == 1) error = sooptcopyout(sopt, &coptval, 1); else error = sooptcopyout(sopt, &optval, sizeof optval); break; case IP_MULTICAST_LOOP: if (imo == 0) optval = coptval = IP_DEFAULT_MULTICAST_LOOP; else optval = coptval = imo->imo_multicast_loop; INP_UNLOCK(inp); if (sopt->sopt_valsize == 1) error = sooptcopyout(sopt, &coptval, 1); else error = sooptcopyout(sopt, &optval, sizeof optval); break; default: INP_UNLOCK(inp); error = ENOPROTOOPT; break; } INP_UNLOCK_ASSERT(inp); return (error); } /* * Discard the IP multicast options. */ void ip_freemoptions(imo) register struct ip_moptions *imo; { register int i; if (imo != NULL) { for (i = 0; i < imo->imo_num_memberships; ++i) in_delmulti(imo->imo_membership[i]); free(imo, M_IPMOPTS); } } /* * 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 a loopback interface -- evil, but easier than * replicating that code here. */ static void ip_mloopback(ifp, m, dst, hlen) struct ifnet *ifp; register struct mbuf *m; register struct sockaddr_in *dst; int hlen; { register struct ip *ip; struct mbuf *copym; copym = m_copy(m, 0, M_COPYALL); if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen)) copym = m_pullup(copym, hlen); if (copym != NULL) { /* If needed, compute the checksum and mark it as valid. */ if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { in_delayed_cksum(copym); copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID | CSUM_PSEUDO_HDR; copym->m_pkthdr.csum_data = 0xffff; } /* * 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 *); ip->ip_len = htons(ip->ip_len); ip->ip_off = htons(ip->ip_off); ip->ip_sum = 0; ip->ip_sum = in_cksum(copym, hlen); /* * NB: * It's not clear whether there are any lingering * reentrancy problems in other areas which might * be exposed by using ip_input directly (in * particular, everything which modifies the packet * in-place). Yet another option is using the * protosw directly to deliver the looped back * packet. For the moment, we'll err on the side * of safety by using if_simloop(). */ #if 1 /* XXX */ if (dst->sin_family != AF_INET) { printf("ip_mloopback: bad address family %d\n", dst->sin_family); dst->sin_family = AF_INET; } #endif #ifdef notdef copym->m_pkthdr.rcvif = ifp; ip_input(copym); #else if_simloop(ifp, copym, dst->sin_family, 0); #endif } }