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IABSD.fr/src/sys/netinet6/ip6_output.c
nayden
- sys/netinet6/ip6_output.c
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/* $OpenBSD: ip6_output.c,v 1.245 2019/11/29 16:41:01 nayden Exp $ */ /* $KAME: ip6_output.c,v 1.172 2001/03/25 09:55:56 itojun Exp $ */ /* * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. * 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 project 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 PROJECT 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 PROJECT 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. */ /* * 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. * 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_output.c 8.3 (Berkeley) 1/21/94 */ #include "pf.h" #include <sys/param.h> #include <sys/malloc.h> #include <sys/mbuf.h> #include <sys/errno.h> #include <sys/protosw.h> #include <sys/socket.h> #include <sys/socketvar.h> #include <sys/proc.h> #include <sys/systm.h> #include <net/if.h> #include <net/if_var.h> #include <net/if_enc.h> #include <net/route.h> #include <netinet/in.h> #include <netinet/ip.h> #include <netinet/in_pcb.h> #include <netinet/udp.h> #include <netinet/tcp.h> #include <netinet/ip_var.h> #include <netinet/tcp_timer.h> #include <netinet/tcp_var.h> #include <netinet/udp_var.h> #include <netinet6/in6_var.h> #include <netinet/ip6.h> #include <netinet/icmp6.h> #include <netinet6/ip6_var.h> #include <netinet6/nd6.h> #include <netinet6/ip6protosw.h> #include <crypto/idgen.h> #if NPF > 0 #include <net/pfvar.h> #endif #ifdef IPSEC #include <netinet/ip_ipsp.h> #include <netinet/ip_ah.h> #include <netinet/ip_esp.h> #endif /* IPSEC */ struct ip6_exthdrs { struct mbuf *ip6e_ip6; struct mbuf *ip6e_hbh; struct mbuf *ip6e_dest1; struct mbuf *ip6e_rthdr; struct mbuf *ip6e_dest2; }; int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **, int, int); int ip6_getpcbopt(struct ip6_pktopts *, int, struct mbuf *); int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *, int, int, int); int ip6_setmoptions(int, struct ip6_moptions **, struct mbuf *, unsigned int); int ip6_getmoptions(int, struct ip6_moptions *, struct mbuf *); int ip6_copyexthdr(struct mbuf **, caddr_t, int); int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int, struct ip6_frag **); int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t); int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *); int ip6_getpmtu(struct rtentry *, struct ifnet *, u_long *); int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *); static __inline u_int16_t __attribute__((__unused__)) in6_cksum_phdr(const struct in6_addr *, const struct in6_addr *, u_int32_t, u_int32_t); void in6_delayed_cksum(struct mbuf *, u_int8_t); /* Context for non-repeating IDs */ struct idgen32_ctx ip6_id_ctx; /* * IP6 output. The packet in mbuf chain m contains a skeletal IP6 * header (with pri, len, nxt, hlim, src, dst). * This function may modify ver and hlim only. * The mbuf chain containing the packet will be freed. * The mbuf opt, if present, will not be freed. * * type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and * nd_ifinfo.linkmtu is u_int32_t. so we use u_long to hold largest one, * which is rt_mtu. */ int ip6_output(struct mbuf *m0, struct ip6_pktopts *opt, struct route_in6 *ro, int flags, struct ip6_moptions *im6o, struct inpcb *inp) { struct ip6_hdr *ip6; struct ifnet *ifp = NULL; struct mbuf *m = m0; int hlen, tlen; struct route_in6 ip6route; struct rtentry *rt = NULL; struct sockaddr_in6 *dst, dstsock; int error = 0; u_long mtu; int dontfrag; u_int16_t src_scope, dst_scope; u_int32_t optlen = 0, plen = 0, unfragpartlen = 0; struct ip6_exthdrs exthdrs; struct in6_addr finaldst; struct route_in6 *ro_pmtu = NULL; int hdrsplit = 0; u_int8_t sproto = 0; #ifdef IPSEC struct tdb *tdb = NULL; #endif /* IPSEC */ #ifdef IPSEC if (inp && (inp->inp_flags & INP_IPV6) == 0) panic("%s: IPv4 pcb is passed", __func__); #endif /* IPSEC */ ip6 = mtod(m, struct ip6_hdr *); finaldst = ip6->ip6_dst; #define MAKE_EXTHDR(hp, mp) \ do { \ if (hp) { \ struct ip6_ext *eh = (struct ip6_ext *)(hp); \ error = ip6_copyexthdr((mp), (caddr_t)(hp), \ ((eh)->ip6e_len + 1) << 3); \ if (error) \ goto freehdrs; \ } \ } while (0) bzero(&exthdrs, sizeof(exthdrs)); if (opt) { /* Hop-by-Hop options header */ MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh); /* Destination options header(1st part) */ MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1); /* Routing header */ MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr); /* Destination options header(2nd part) */ MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2); } #ifdef IPSEC if (ipsec_in_use || inp) { tdb = ip6_output_ipsec_lookup(m, &error, inp); if (error != 0) { /* * -EINVAL is used to indicate that the packet should * be silently dropped, typically because we've asked * key management for an SA. */ if (error == -EINVAL) /* Should silently drop packet */ error = 0; goto freehdrs; } } #endif /* IPSEC */ /* * Calculate the total length of the extension header chain. * Keep the length of the unfragmentable part for fragmentation. */ optlen = 0; if (exthdrs.ip6e_hbh) optlen += exthdrs.ip6e_hbh->m_len; if (exthdrs.ip6e_dest1) optlen += exthdrs.ip6e_dest1->m_len; if (exthdrs.ip6e_rthdr) optlen += exthdrs.ip6e_rthdr->m_len; unfragpartlen = optlen + sizeof(struct ip6_hdr); /* NOTE: we don't add AH/ESP length here. do that later. */ if (exthdrs.ip6e_dest2) optlen += exthdrs.ip6e_dest2->m_len; /* * If we need IPsec, or there is at least one extension header, * separate IP6 header from the payload. */ if ((sproto || optlen) && !hdrsplit) { if ((error = ip6_splithdr(m, &exthdrs)) != 0) { m = NULL; goto freehdrs; } m = exthdrs.ip6e_ip6; hdrsplit++; } /* adjust pointer */ ip6 = mtod(m, struct ip6_hdr *); /* adjust mbuf packet header length */ m->m_pkthdr.len += optlen; plen = m->m_pkthdr.len - sizeof(*ip6); /* If this is a jumbo payload, insert a jumbo payload option. */ if (plen > IPV6_MAXPACKET) { if (!hdrsplit) { if ((error = ip6_splithdr(m, &exthdrs)) != 0) { m = NULL; goto freehdrs; } m = exthdrs.ip6e_ip6; hdrsplit++; } /* adjust pointer */ ip6 = mtod(m, struct ip6_hdr *); if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0) goto freehdrs; ip6->ip6_plen = 0; } else ip6->ip6_plen = htons(plen); /* * Concatenate headers and fill in next header fields. * Here we have, on "m" * IPv6 payload * and we insert headers accordingly. Finally, we should be getting: * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload] * * during the header composing process, "m" points to IPv6 header. * "mprev" points to an extension header prior to esp. */ { u_char *nexthdrp = &ip6->ip6_nxt; struct mbuf *mprev = m; /* * we treat dest2 specially. this makes IPsec processing * much easier. the goal here is to make mprev point the * mbuf prior to dest2. * * result: IPv6 dest2 payload * m and mprev will point to IPv6 header. */ if (exthdrs.ip6e_dest2) { if (!hdrsplit) panic("%s: assumption failed: hdr not split", __func__); exthdrs.ip6e_dest2->m_next = m->m_next; m->m_next = exthdrs.ip6e_dest2; *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt; ip6->ip6_nxt = IPPROTO_DSTOPTS; } #define MAKE_CHAIN(m, mp, p, i)\ do {\ if (m) {\ if (!hdrsplit) \ panic("assumption failed: hdr not split"); \ *mtod((m), u_char *) = *(p);\ *(p) = (i);\ p = mtod((m), u_char *);\ (m)->m_next = (mp)->m_next;\ (mp)->m_next = (m);\ (mp) = (m);\ }\ } while (0) /* * result: IPv6 hbh dest1 rthdr dest2 payload * m will point to IPv6 header. mprev will point to the * extension header prior to dest2 (rthdr in the above case). */ MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS); MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp, IPPROTO_DSTOPTS); MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp, IPPROTO_ROUTING); } /* * If there is a routing header, replace the destination address field * with the first hop of the routing header. */ if (exthdrs.ip6e_rthdr) { struct ip6_rthdr *rh; struct ip6_rthdr0 *rh0; struct in6_addr *addr; rh = (struct ip6_rthdr *)(mtod(exthdrs.ip6e_rthdr, struct ip6_rthdr *)); switch (rh->ip6r_type) { case IPV6_RTHDR_TYPE_0: rh0 = (struct ip6_rthdr0 *)rh; addr = (struct in6_addr *)(rh0 + 1); ip6->ip6_dst = addr[0]; bcopy(&addr[1], &addr[0], sizeof(struct in6_addr) * (rh0->ip6r0_segleft - 1)); addr[rh0->ip6r0_segleft - 1] = finaldst; break; default: /* is it possible? */ error = EINVAL; goto bad; } } /* Source address validation */ if (!(flags & IPV6_UNSPECSRC) && IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) { /* * XXX: we can probably assume validation in the caller, but * we explicitly check the address here for safety. */ error = EOPNOTSUPP; ip6stat_inc(ip6s_badscope); goto bad; } if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) { error = EOPNOTSUPP; ip6stat_inc(ip6s_badscope); goto bad; } ip6stat_inc(ip6s_localout); /* * Route packet. */ #if NPF > 0 reroute: #endif /* initialize cached route */ if (ro == NULL) { ro = &ip6route; bzero((caddr_t)ro, sizeof(*ro)); } ro_pmtu = ro; if (opt && opt->ip6po_rthdr) ro = &opt->ip6po_route; dst = &ro->ro_dst; /* * if specified, try to fill in the traffic class field. * do not override if a non-zero value is already set. * we check the diffserv field and the ecn field separately. */ if (opt && opt->ip6po_tclass >= 0) { int mask = 0; if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0) mask |= 0xfc; if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0) mask |= 0x03; if (mask != 0) ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20); } /* fill in or override the hop limit field, if necessary. */ if (opt && opt->ip6po_hlim != -1) ip6->ip6_hlim = opt->ip6po_hlim & 0xff; else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { if (im6o != NULL) ip6->ip6_hlim = im6o->im6o_hlim; else ip6->ip6_hlim = ip6_defmcasthlim; } #ifdef IPSEC if (tdb) { /* * XXX what should we do if ip6_hlim == 0 and the * packet gets tunneled? */ /* * if we are source-routing, do not attempt to tunnel the * packet just because ip6_dst is different from what tdb has. * XXX */ error = ip6_output_ipsec_send(tdb, m, exthdrs.ip6e_rthdr ? 1 : 0, 0); goto done; } #endif /* IPSEC */ bzero(&dstsock, sizeof(dstsock)); dstsock.sin6_family = AF_INET6; dstsock.sin6_addr = ip6->ip6_dst; dstsock.sin6_len = sizeof(dstsock); ro->ro_tableid = m->m_pkthdr.ph_rtableid; if (IN6_IS_ADDR_MULTICAST(&dstsock.sin6_addr)) { struct in6_pktinfo *pi = NULL; /* * If the caller specify the outgoing interface * explicitly, use it. */ if (opt != NULL && (pi = opt->ip6po_pktinfo) != NULL) ifp = if_get(pi->ipi6_ifindex); if (ifp == NULL && im6o != NULL) ifp = if_get(im6o->im6o_ifidx); } if (ifp == NULL) { rt = in6_selectroute(&dstsock, opt, ro, ro->ro_tableid); if (rt == NULL) { ip6stat_inc(ip6s_noroute); error = EHOSTUNREACH; goto bad; } if (ISSET(rt->rt_flags, RTF_LOCAL)) ifp = if_get(rtable_loindex(m->m_pkthdr.ph_rtableid)); else ifp = if_get(rt->rt_ifidx); /* * We aren't using rtisvalid() here because the UP/DOWN state * machine is broken with some Ethernet drivers like em(4). * As a result we might try to use an invalid cached route * entry while an interface is being detached. */ if (ifp == NULL) { ip6stat_inc(ip6s_noroute); error = EHOSTUNREACH; goto bad; } } else { *dst = dstsock; } if (rt && (rt->rt_flags & RTF_GATEWAY) && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) dst = satosin6(rt->rt_gateway); if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { /* Unicast */ m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */ } else { /* Multicast */ m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST; /* * Confirm that the outgoing interface supports multicast. */ if ((ifp->if_flags & IFF_MULTICAST) == 0) { ip6stat_inc(ip6s_noroute); error = ENETUNREACH; goto bad; } if ((im6o == NULL || im6o->im6o_loop) && in6_hasmulti(&ip6->ip6_dst, ifp)) { /* * If we belong to the destination multicast group * on the outgoing interface, and the caller did not * forbid loopback, loop back a copy. * Can't defer TCP/UDP checksumming, do the * computation now. */ in6_proto_cksum_out(m, NULL); ip6_mloopback(ifp, m, dst); } #ifdef MROUTING 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 * IPV6_FORWARDING flag to prevent infinite recursion. * * Multicasts that are looped back by ip6_mloopback(), * above, will be forwarded by the ip6_input() routine, * if necessary. */ if (ip6_mforwarding && ip6_mrouter[ifp->if_rdomain] && (flags & IPV6_FORWARDING) == 0) { if (ip6_mforward(ip6, ifp, m) != 0) { m_freem(m); goto done; } } } #endif /* * Multicasts with a hoplimit 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 ip6_mloopback() will * loop back a copy if this host actually belongs to the * destination group on the loopback interface. */ if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) || IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) { m_freem(m); goto done; } } /* * If this packet is going trough a loopback interface we wont * be able to restore its scope ID using the interface index. */ if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) { if (ifp->if_flags & IFF_LOOPBACK) src_scope = ip6->ip6_src.s6_addr16[1]; ip6->ip6_src.s6_addr16[1] = 0; } if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) { if (ifp->if_flags & IFF_LOOPBACK) dst_scope = ip6->ip6_dst.s6_addr16[1]; ip6->ip6_dst.s6_addr16[1] = 0; } /* Determine path MTU. */ if ((error = ip6_getpmtu(ro_pmtu->ro_rt, ifp, &mtu)) != 0) goto bad; /* * The caller of this function may specify to use the minimum MTU * in some cases. * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU * setting. The logic is a bit complicated; by default, unicast * packets will follow path MTU while multicast packets will be sent at * the minimum MTU. If IP6PO_MINMTU_ALL is specified, all packets * including unicast ones will be sent at the minimum MTU. Multicast * packets will always be sent at the minimum MTU unless * IP6PO_MINMTU_DISABLE is explicitly specified. * See RFC 3542 for more details. */ if (mtu > IPV6_MMTU) { if ((flags & IPV6_MINMTU)) mtu = IPV6_MMTU; else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL) mtu = IPV6_MMTU; else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && (opt == NULL || opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) { mtu = IPV6_MMTU; } } /* * If the outgoing packet contains a hop-by-hop options header, * it must be examined and processed even by the source node. * (RFC 2460, section 4.) */ if (exthdrs.ip6e_hbh) { struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *); u_int32_t dummy1; /* XXX unused */ u_int32_t dummy2; /* XXX unused */ m->m_pkthdr.ph_ifidx = ifp->if_index; if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1), ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh), &dummy1, &dummy2) < 0) { /* m was already freed at this point */ error = EINVAL;/* better error? */ goto done; } m->m_pkthdr.ph_ifidx = 0; } #if NPF > 0 if (pf_test(AF_INET6, PF_OUT, ifp, &m) != PF_PASS) { error = EHOSTUNREACH; m_freem(m); goto done; } if (m == NULL) goto done; ip6 = mtod(m, struct ip6_hdr *); if ((m->m_pkthdr.pf.flags & (PF_TAG_REROUTE | PF_TAG_GENERATED)) == (PF_TAG_REROUTE | PF_TAG_GENERATED)) { /* already rerun the route lookup, go on */ m->m_pkthdr.pf.flags &= ~(PF_TAG_GENERATED | PF_TAG_REROUTE); } else if (m->m_pkthdr.pf.flags & PF_TAG_REROUTE) { /* tag as generated to skip over pf_test on rerun */ m->m_pkthdr.pf.flags |= PF_TAG_GENERATED; finaldst = ip6->ip6_dst; ro = NULL; if_put(ifp); /* drop reference since destination changed */ ifp = NULL; goto reroute; } #endif /* * If the packet is not going on the wire it can be destinated * to any local address. In this case do not clear its scopes * to let ip6_input() find a matching local route. */ if (ifp->if_flags & IFF_LOOPBACK) { if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) ip6->ip6_src.s6_addr16[1] = src_scope; if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) ip6->ip6_dst.s6_addr16[1] = dst_scope; } in6_proto_cksum_out(m, ifp); /* * Send the packet to the outgoing interface. * If necessary, do IPv6 fragmentation before sending. * * the logic here is rather complex: * 1: normal case (dontfrag == 0) * 1-a: send as is if tlen <= path mtu * 1-b: fragment if tlen > path mtu * * 2: if user asks us not to fragment (dontfrag == 1) * 2-a: send as is if tlen <= interface mtu * 2-b: error if tlen > interface mtu */ tlen = m->m_pkthdr.len; if (ISSET(m->m_pkthdr.csum_flags, M_IPV6_DF_OUT)) { CLR(m->m_pkthdr.csum_flags, M_IPV6_DF_OUT); dontfrag = 1; } else if (opt && ISSET(opt->ip6po_flags, IP6PO_DONTFRAG)) dontfrag = 1; else dontfrag = 0; if (dontfrag && tlen > ifp->if_mtu) { /* case 2-b */ error = EMSGSIZE; goto bad; } /* * transmit packet without fragmentation */ if (dontfrag || (tlen <= mtu)) { /* case 1-a and 2-a */ error = ifp->if_output(ifp, m, sin6tosa(dst), ro->ro_rt); goto done; } /* * try to fragment the packet. case 1-b */ if (mtu < IPV6_MMTU) { /* path MTU cannot be less than IPV6_MMTU */ error = EMSGSIZE; goto bad; } else if (ip6->ip6_plen == 0) { /* jumbo payload cannot be fragmented */ error = EMSGSIZE; goto bad; } else { u_char nextproto; #if 0 struct ip6ctlparam ip6cp; u_int32_t mtu32; #endif /* * Too large for the destination or interface; * fragment if possible. * Must be able to put at least 8 bytes per fragment. */ hlen = unfragpartlen; if (mtu > IPV6_MAXPACKET) mtu = IPV6_MAXPACKET; /* * Change the next header field of the last header in the * unfragmentable part. */ if (exthdrs.ip6e_rthdr) { nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *); *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT; } else if (exthdrs.ip6e_dest1) { nextproto = *mtod(exthdrs.ip6e_dest1, u_char *); *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT; } else if (exthdrs.ip6e_hbh) { nextproto = *mtod(exthdrs.ip6e_hbh, u_char *); *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT; } else { nextproto = ip6->ip6_nxt; ip6->ip6_nxt = IPPROTO_FRAGMENT; } m0 = m; error = ip6_fragment(m0, hlen, nextproto, mtu); if (error) ip6stat_inc(ip6s_odropped); } /* * Remove leading garbages. */ m = m0->m_nextpkt; m0->m_nextpkt = 0; m_freem(m0); for (m0 = m; m; m = m0) { m0 = m->m_nextpkt; m->m_nextpkt = 0; if (error == 0) { ip6stat_inc(ip6s_ofragments); error = ifp->if_output(ifp, m, sin6tosa(dst), ro->ro_rt); } else m_freem(m); } if (error == 0) ip6stat_inc(ip6s_fragmented); done: if_put(ifp); if (ro == &ip6route && ro->ro_rt) { rtfree(ro->ro_rt); } else if (ro_pmtu == &ip6route && ro_pmtu->ro_rt) { rtfree(ro_pmtu->ro_rt); } return (error); freehdrs: m_freem(exthdrs.ip6e_hbh); /* m_freem will check if mbuf is 0 */ m_freem(exthdrs.ip6e_dest1); m_freem(exthdrs.ip6e_rthdr); m_freem(exthdrs.ip6e_dest2); /* FALLTHROUGH */ bad: m_freem(m); goto done; } int ip6_fragment(struct mbuf *m0, int hlen, u_char nextproto, u_long mtu) { struct mbuf *m, **mnext, *m_frgpart; struct ip6_hdr *mhip6; struct ip6_frag *ip6f; u_int32_t id; int tlen, len, off; int error; id = htonl(ip6_randomid()); mnext = &m0->m_nextpkt; *mnext = NULL; tlen = m0->m_pkthdr.len; len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7; if (len < 8) return (EMSGSIZE); /* * Loop through length of segment after first fragment, * make new header and copy data of each part and link onto * chain. */ for (off = hlen; off < tlen; off += len) { struct mbuf *mlast; if ((m = m_gethdr(M_DONTWAIT, MT_HEADER)) == NULL) return (ENOBUFS); *mnext = m; mnext = &m->m_nextpkt; if ((error = m_dup_pkthdr(m, m0, M_DONTWAIT)) != 0) return (error); m->m_data += max_linkhdr; mhip6 = mtod(m, struct ip6_hdr *); *mhip6 = *mtod(m0, struct ip6_hdr *); m->m_len = sizeof(*mhip6); if ((error = ip6_insertfraghdr(m0, m, hlen, &ip6f)) != 0) return (error); ip6f->ip6f_offlg = htons((u_int16_t)((off - hlen) & ~7)); if (off + len >= tlen) len = tlen - off; else ip6f->ip6f_offlg |= IP6F_MORE_FRAG; mhip6->ip6_plen = htons((u_int16_t)(len + hlen + sizeof(*ip6f) - sizeof(struct ip6_hdr))); if ((m_frgpart = m_copym(m0, off, len, M_DONTWAIT)) == NULL) return (ENOBUFS); for (mlast = m; mlast->m_next; mlast = mlast->m_next) ; mlast->m_next = m_frgpart; m->m_pkthdr.len = len + hlen + sizeof(*ip6f); ip6f->ip6f_reserved = 0; ip6f->ip6f_ident = id; ip6f->ip6f_nxt = nextproto; } return (0); } int ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen) { struct mbuf *m; if (hlen > MCLBYTES) return (ENOBUFS); /* XXX */ MGET(m, M_DONTWAIT, MT_DATA); if (!m) return (ENOBUFS); if (hlen > MLEN) { MCLGET(m, M_DONTWAIT); if ((m->m_flags & M_EXT) == 0) { m_free(m); return (ENOBUFS); } } m->m_len = hlen; if (hdr) memcpy(mtod(m, caddr_t), hdr, hlen); *mp = m; return (0); } /* * Insert jumbo payload option. */ int ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen) { struct mbuf *mopt; u_int8_t *optbuf; u_int32_t v; #define JUMBOOPTLEN 8 /* length of jumbo payload option and padding */ /* * If there is no hop-by-hop options header, allocate new one. * If there is one but it doesn't have enough space to store the * jumbo payload option, allocate a cluster to store the whole options. * Otherwise, use it to store the options. */ if (exthdrs->ip6e_hbh == 0) { MGET(mopt, M_DONTWAIT, MT_DATA); if (mopt == NULL) return (ENOBUFS); mopt->m_len = JUMBOOPTLEN; optbuf = mtod(mopt, u_int8_t *); optbuf[1] = 0; /* = ((JUMBOOPTLEN) >> 3) - 1 */ exthdrs->ip6e_hbh = mopt; } else { struct ip6_hbh *hbh; mopt = exthdrs->ip6e_hbh; if (m_trailingspace(mopt) < JUMBOOPTLEN) { /* * XXX assumption: * - exthdrs->ip6e_hbh is not referenced from places * other than exthdrs. * - exthdrs->ip6e_hbh is not an mbuf chain. */ int oldoptlen = mopt->m_len; struct mbuf *n; /* * XXX: give up if the whole (new) hbh header does * not fit even in an mbuf cluster. */ if (oldoptlen + JUMBOOPTLEN > MCLBYTES) return (ENOBUFS); /* * As a consequence, we must always prepare a cluster * at this point. */ MGET(n, M_DONTWAIT, MT_DATA); if (n) { MCLGET(n, M_DONTWAIT); if ((n->m_flags & M_EXT) == 0) { m_freem(n); n = NULL; } } if (!n) return (ENOBUFS); n->m_len = oldoptlen + JUMBOOPTLEN; memcpy(mtod(n, caddr_t), mtod(mopt, caddr_t), oldoptlen); optbuf = mtod(n, u_int8_t *) + oldoptlen; m_freem(mopt); mopt = exthdrs->ip6e_hbh = n; } else { optbuf = mtod(mopt, u_int8_t *) + mopt->m_len; mopt->m_len += JUMBOOPTLEN; } optbuf[0] = IP6OPT_PADN; optbuf[1] = 0; /* * Adjust the header length according to the pad and * the jumbo payload option. */ hbh = mtod(mopt, struct ip6_hbh *); hbh->ip6h_len += (JUMBOOPTLEN >> 3); } /* fill in the option. */ optbuf[2] = IP6OPT_JUMBO; optbuf[3] = 4; v = (u_int32_t)htonl(plen + JUMBOOPTLEN); memcpy(&optbuf[4], &v, sizeof(u_int32_t)); /* finally, adjust the packet header length */ exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN; return (0); #undef JUMBOOPTLEN } /* * Insert fragment header and copy unfragmentable header portions. */ int ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen, struct ip6_frag **frghdrp) { struct mbuf *n, *mlast; if (hlen > sizeof(struct ip6_hdr)) { n = m_copym(m0, sizeof(struct ip6_hdr), hlen - sizeof(struct ip6_hdr), M_DONTWAIT); if (n == NULL) return (ENOBUFS); m->m_next = n; } else n = m; /* Search for the last mbuf of unfragmentable part. */ for (mlast = n; mlast->m_next; mlast = mlast->m_next) ; if ((mlast->m_flags & M_EXT) == 0 && m_trailingspace(mlast) >= sizeof(struct ip6_frag)) { /* use the trailing space of the last mbuf for the fragment hdr */ *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) + mlast->m_len); mlast->m_len += sizeof(struct ip6_frag); m->m_pkthdr.len += sizeof(struct ip6_frag); } else { /* allocate a new mbuf for the fragment header */ struct mbuf *mfrg; MGET(mfrg, M_DONTWAIT, MT_DATA); if (mfrg == NULL) return (ENOBUFS); mfrg->m_len = sizeof(struct ip6_frag); *frghdrp = mtod(mfrg, struct ip6_frag *); mlast->m_next = mfrg; } return (0); } int ip6_getpmtu(struct rtentry *rt, struct ifnet *ifp, u_long *mtup) { u_int32_t mtu = 0; int error = 0; if (rt != NULL) { mtu = rt->rt_mtu; if (mtu == 0) mtu = ifp->if_mtu; else if (mtu < IPV6_MMTU) { /* RFC8021 IPv6 Atomic Fragments Considered Harmful */ mtu = IPV6_MMTU; } else if (mtu > ifp->if_mtu) { /* * The MTU on the route is larger than the MTU on * the interface! This shouldn't happen, unless the * MTU of the interface has been changed after the * interface was brought up. Change the MTU in the * route to match the interface MTU (as long as the * field isn't locked). */ mtu = ifp->if_mtu; if (!(rt->rt_locks & RTV_MTU)) rt->rt_mtu = mtu; } } else { mtu = ifp->if_mtu; } *mtup = mtu; return (error); } /* * IP6 socket option processing. */ int ip6_ctloutput(int op, struct socket *so, int level, int optname, struct mbuf *m) { int privileged, optdatalen, uproto; void *optdata; struct inpcb *inp = sotoinpcb(so); int error, optval; struct proc *p = curproc; /* For IPsec and rdomain */ u_int rtid = 0; error = optval = 0; privileged = (inp->inp_socket->so_state & SS_PRIV); uproto = (int)so->so_proto->pr_protocol; if (level != IPPROTO_IPV6) return (EINVAL); switch (op) { case PRCO_SETOPT: switch (optname) { /* * Use of some Hop-by-Hop options or some * Destination options, might require special * privilege. That is, normal applications * (without special privilege) might be forbidden * from setting certain options in outgoing packets, * and might never see certain options in received * packets. [RFC 2292 Section 6] * KAME specific note: * KAME prevents non-privileged users from sending or * receiving ANY hbh/dst options in order to avoid * overhead of parsing options in the kernel. */ case IPV6_RECVHOPOPTS: case IPV6_RECVDSTOPTS: if (!privileged) { error = EPERM; break; } /* FALLTHROUGH */ case IPV6_UNICAST_HOPS: case IPV6_MINHOPCOUNT: case IPV6_HOPLIMIT: case IPV6_RECVPKTINFO: case IPV6_RECVHOPLIMIT: case IPV6_RECVRTHDR: case IPV6_RECVPATHMTU: case IPV6_RECVTCLASS: case IPV6_V6ONLY: case IPV6_AUTOFLOWLABEL: case IPV6_RECVDSTPORT: if (m == NULL || m->m_len != sizeof(int)) { error = EINVAL; break; } optval = *mtod(m, int *); switch (optname) { case IPV6_UNICAST_HOPS: if (optval < -1 || optval >= 256) error = EINVAL; else { /* -1 = kernel default */ inp->inp_hops = optval; } break; case IPV6_MINHOPCOUNT: if (optval < 0 || optval > 255) error = EINVAL; else inp->inp_ip6_minhlim = optval; break; #define OPTSET(bit) \ do { \ if (optval) \ inp->inp_flags |= (bit); \ else \ inp->inp_flags &= ~(bit); \ } while (/*CONSTCOND*/ 0) #define OPTBIT(bit) (inp->inp_flags & (bit) ? 1 : 0) case IPV6_RECVPKTINFO: OPTSET(IN6P_PKTINFO); break; case IPV6_HOPLIMIT: { struct ip6_pktopts **optp; optp = &inp->inp_outputopts6; error = ip6_pcbopt(IPV6_HOPLIMIT, (u_char *)&optval, sizeof(optval), optp, privileged, uproto); break; } case IPV6_RECVHOPLIMIT: OPTSET(IN6P_HOPLIMIT); break; case IPV6_RECVHOPOPTS: OPTSET(IN6P_HOPOPTS); break; case IPV6_RECVDSTOPTS: OPTSET(IN6P_DSTOPTS); break; case IPV6_RECVRTHDR: OPTSET(IN6P_RTHDR); break; case IPV6_RECVPATHMTU: /* * We ignore this option for TCP * sockets. * (RFC3542 leaves this case * unspecified.) */ if (uproto != IPPROTO_TCP) OPTSET(IN6P_MTU); break; case IPV6_V6ONLY: /* * make setsockopt(IPV6_V6ONLY) * available only prior to bind(2). * see ipng mailing list, Jun 22 2001. */ if (inp->inp_lport || !IN6_IS_ADDR_UNSPECIFIED(&inp->inp_laddr6)) { error = EINVAL; break; } /* No support for IPv4-mapped addresses. */ if (!optval) error = EINVAL; else error = 0; break; case IPV6_RECVTCLASS: OPTSET(IN6P_TCLASS); break; case IPV6_AUTOFLOWLABEL: OPTSET(IN6P_AUTOFLOWLABEL); break; case IPV6_RECVDSTPORT: OPTSET(IN6P_RECVDSTPORT); break; } break; case IPV6_TCLASS: case IPV6_DONTFRAG: case IPV6_USE_MIN_MTU: if (m == NULL || m->m_len != sizeof(optval)) { error = EINVAL; break; } optval = *mtod(m, int *); { struct ip6_pktopts **optp; optp = &inp->inp_outputopts6; error = ip6_pcbopt(optname, (u_char *)&optval, sizeof(optval), optp, privileged, uproto); break; } case IPV6_PKTINFO: case IPV6_HOPOPTS: case IPV6_RTHDR: case IPV6_DSTOPTS: case IPV6_RTHDRDSTOPTS: { /* new advanced API (RFC3542) */ u_char *optbuf; int optbuflen; struct ip6_pktopts **optp; if (m && m->m_next) { error = EINVAL; /* XXX */ break; } if (m) { optbuf = mtod(m, u_char *); optbuflen = m->m_len; } else { optbuf = NULL; optbuflen = 0; } optp = &inp->inp_outputopts6; error = ip6_pcbopt(optname, optbuf, optbuflen, optp, privileged, uproto); break; } #undef OPTSET case IPV6_MULTICAST_IF: case IPV6_MULTICAST_HOPS: case IPV6_MULTICAST_LOOP: case IPV6_JOIN_GROUP: case IPV6_LEAVE_GROUP: error = ip6_setmoptions(optname, &inp->inp_moptions6, m, inp->inp_rtableid); break; case IPV6_PORTRANGE: if (m == NULL || m->m_len != sizeof(int)) { error = EINVAL; break; } optval = *mtod(m, int *); switch (optval) { case IPV6_PORTRANGE_DEFAULT: inp->inp_flags &= ~(IN6P_LOWPORT); inp->inp_flags &= ~(IN6P_HIGHPORT); break; case IPV6_PORTRANGE_HIGH: inp->inp_flags &= ~(IN6P_LOWPORT); inp->inp_flags |= IN6P_HIGHPORT; break; case IPV6_PORTRANGE_LOW: inp->inp_flags &= ~(IN6P_HIGHPORT); inp->inp_flags |= IN6P_LOWPORT; break; default: error = EINVAL; break; } break; case IPSEC6_OUTSA: error = EINVAL; break; case IPV6_AUTH_LEVEL: case IPV6_ESP_TRANS_LEVEL: case IPV6_ESP_NETWORK_LEVEL: case IPV6_IPCOMP_LEVEL: #ifndef IPSEC error = EINVAL; #else if (m == NULL || m->m_len != sizeof(int)) { error = EINVAL; break; } optval = *mtod(m, int *); if (optval < IPSEC_LEVEL_BYPASS || optval > IPSEC_LEVEL_UNIQUE) { error = EINVAL; break; } switch (optname) { case IPV6_AUTH_LEVEL: if (optval < IPSEC_AUTH_LEVEL_DEFAULT && suser(p)) { error = EACCES; break; } inp->inp_seclevel[SL_AUTH] = optval; break; case IPV6_ESP_TRANS_LEVEL: if (optval < IPSEC_ESP_TRANS_LEVEL_DEFAULT && suser(p)) { error = EACCES; break; } inp->inp_seclevel[SL_ESP_TRANS] = optval; break; case IPV6_ESP_NETWORK_LEVEL: if (optval < IPSEC_ESP_NETWORK_LEVEL_DEFAULT && suser(p)) { error = EACCES; break; } inp->inp_seclevel[SL_ESP_NETWORK] = optval; break; case IPV6_IPCOMP_LEVEL: if (optval < IPSEC_IPCOMP_LEVEL_DEFAULT && suser(p)) { error = EACCES; break; } inp->inp_seclevel[SL_IPCOMP] = optval; break; } #endif break; case SO_RTABLE: if (m == NULL || m->m_len < sizeof(u_int)) { error = EINVAL; break; } rtid = *mtod(m, u_int *); if (inp->inp_rtableid == rtid) break; /* needs privileges to switch when already set */ if (p->p_p->ps_rtableid != rtid && p->p_p->ps_rtableid != 0 && (error = suser(p)) != 0) break; /* table must exist */ if (!rtable_exists(rtid)) { error = EINVAL; break; } if (inp->inp_lport) { error = EBUSY; break; } inp->inp_rtableid = rtid; in_pcbrehash(inp); break; case IPV6_PIPEX: if (m != NULL && m->m_len == sizeof(int)) inp->inp_pipex = *mtod(m, int *); else error = EINVAL; break; default: error = ENOPROTOOPT; break; } break; case PRCO_GETOPT: switch (optname) { case IPV6_RECVHOPOPTS: case IPV6_RECVDSTOPTS: case IPV6_UNICAST_HOPS: case IPV6_MINHOPCOUNT: case IPV6_RECVPKTINFO: case IPV6_RECVHOPLIMIT: case IPV6_RECVRTHDR: case IPV6_RECVPATHMTU: case IPV6_V6ONLY: case IPV6_PORTRANGE: case IPV6_RECVTCLASS: case IPV6_AUTOFLOWLABEL: case IPV6_RECVDSTPORT: switch (optname) { case IPV6_RECVHOPOPTS: optval = OPTBIT(IN6P_HOPOPTS); break; case IPV6_RECVDSTOPTS: optval = OPTBIT(IN6P_DSTOPTS); break; case IPV6_UNICAST_HOPS: optval = inp->inp_hops; break; case IPV6_MINHOPCOUNT: optval = inp->inp_ip6_minhlim; break; case IPV6_RECVPKTINFO: optval = OPTBIT(IN6P_PKTINFO); break; case IPV6_RECVHOPLIMIT: optval = OPTBIT(IN6P_HOPLIMIT); break; case IPV6_RECVRTHDR: optval = OPTBIT(IN6P_RTHDR); break; case IPV6_RECVPATHMTU: optval = OPTBIT(IN6P_MTU); break; case IPV6_V6ONLY: optval = 1; break; case IPV6_PORTRANGE: { int flags; flags = inp->inp_flags; if (flags & IN6P_HIGHPORT) optval = IPV6_PORTRANGE_HIGH; else if (flags & IN6P_LOWPORT) optval = IPV6_PORTRANGE_LOW; else optval = 0; break; } case IPV6_RECVTCLASS: optval = OPTBIT(IN6P_TCLASS); break; case IPV6_AUTOFLOWLABEL: optval = OPTBIT(IN6P_AUTOFLOWLABEL); break; case IPV6_RECVDSTPORT: optval = OPTBIT(IN6P_RECVDSTPORT); break; } if (error) break; m->m_len = sizeof(int); *mtod(m, int *) = optval; break; case IPV6_PATHMTU: { u_long pmtu = 0; struct ip6_mtuinfo mtuinfo; struct ifnet *ifp; struct rtentry *rt; if (!(so->so_state & SS_ISCONNECTED)) return (ENOTCONN); rt = in_pcbrtentry(inp); if (!rtisvalid(rt)) return (EHOSTUNREACH); ifp = if_get(rt->rt_ifidx); if (ifp == NULL) return (EHOSTUNREACH); /* * XXX: we dot not consider the case of source * routing, or optional information to specify * the outgoing interface. */ error = ip6_getpmtu(rt, ifp, &pmtu); if_put(ifp); if (error) break; if (pmtu > IPV6_MAXPACKET) pmtu = IPV6_MAXPACKET; bzero(&mtuinfo, sizeof(mtuinfo)); mtuinfo.ip6m_mtu = (u_int32_t)pmtu; optdata = (void *)&mtuinfo; optdatalen = sizeof(mtuinfo); if (optdatalen > MCLBYTES) return (EMSGSIZE); /* XXX */ if (optdatalen > MLEN) MCLGET(m, M_WAIT); m->m_len = optdatalen; bcopy(optdata, mtod(m, void *), optdatalen); break; } case IPV6_PKTINFO: case IPV6_HOPOPTS: case IPV6_RTHDR: case IPV6_DSTOPTS: case IPV6_RTHDRDSTOPTS: case IPV6_TCLASS: case IPV6_DONTFRAG: case IPV6_USE_MIN_MTU: error = ip6_getpcbopt(inp->inp_outputopts6, optname, m); break; case IPV6_MULTICAST_IF: case IPV6_MULTICAST_HOPS: case IPV6_MULTICAST_LOOP: case IPV6_JOIN_GROUP: case IPV6_LEAVE_GROUP: error = ip6_getmoptions(optname, inp->inp_moptions6, m); break; case IPSEC6_OUTSA: error = EINVAL; break; case IPV6_AUTH_LEVEL: case IPV6_ESP_TRANS_LEVEL: case IPV6_ESP_NETWORK_LEVEL: case IPV6_IPCOMP_LEVEL: #ifndef IPSEC m->m_len = sizeof(int); *mtod(m, int *) = IPSEC_LEVEL_NONE; #else m->m_len = sizeof(int); switch (optname) { case IPV6_AUTH_LEVEL: optval = inp->inp_seclevel[SL_AUTH]; break; case IPV6_ESP_TRANS_LEVEL: optval = inp->inp_seclevel[SL_ESP_TRANS]; break; case IPV6_ESP_NETWORK_LEVEL: optval = inp->inp_seclevel[SL_ESP_NETWORK]; break; case IPV6_IPCOMP_LEVEL: optval = inp->inp_seclevel[SL_IPCOMP]; break; } *mtod(m, int *) = optval; #endif break; case SO_RTABLE: m->m_len = sizeof(u_int); *mtod(m, u_int *) = optval; break; case IPV6_PIPEX: m->m_len = sizeof(int); *mtod(m, int *) = optval; break; default: error = ENOPROTOOPT; break; } break; } return (error); } int ip6_raw_ctloutput(int op, struct socket *so, int level, int optname, struct mbuf *m) { int error = 0, optval; const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum); struct inpcb *inp = sotoinpcb(so); if (level != IPPROTO_IPV6) return (EINVAL); switch (optname) { case IPV6_CHECKSUM: /* * For ICMPv6 sockets, no modification allowed for checksum * offset, permit "no change" values to help existing apps. * * RFC3542 says: "An attempt to set IPV6_CHECKSUM * for an ICMPv6 socket will fail." * The current behavior does not meet RFC3542. */ switch (op) { case PRCO_SETOPT: if (m == NULL || m->m_len != sizeof(int)) { error = EINVAL; break; } optval = *mtod(m, int *); if (optval < -1 || (optval > 0 && (optval % 2) != 0)) { /* * The API assumes non-negative even offset * values or -1 as a special value. */ error = EINVAL; } else if (so->so_proto->pr_protocol == IPPROTO_ICMPV6) { if (optval != icmp6off) error = EINVAL; } else inp->inp_cksum6 = optval; break; case PRCO_GETOPT: if (so->so_proto->pr_protocol == IPPROTO_ICMPV6) optval = icmp6off; else optval = inp->inp_cksum6; m->m_len = sizeof(int); *mtod(m, int *) = optval; break; default: error = EINVAL; break; } break; default: error = ENOPROTOOPT; break; } return (error); } /* * initialize ip6_pktopts. beware that there are non-zero default values in * the struct. */ void ip6_initpktopts(struct ip6_pktopts *opt) { bzero(opt, sizeof(*opt)); opt->ip6po_hlim = -1; /* -1 means default hop limit */ opt->ip6po_tclass = -1; /* -1 means default traffic class */ opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY; } int ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt, int priv, int uproto) { struct ip6_pktopts *opt; if (*pktopt == NULL) { *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT, M_WAITOK); ip6_initpktopts(*pktopt); } opt = *pktopt; return (ip6_setpktopt(optname, buf, len, opt, priv, 1, uproto)); } int ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct mbuf *m) { void *optdata = NULL; int optdatalen = 0; struct ip6_ext *ip6e; int error = 0; struct in6_pktinfo null_pktinfo; int deftclass = 0, on; int defminmtu = IP6PO_MINMTU_MCASTONLY; switch (optname) { case IPV6_PKTINFO: if (pktopt && pktopt->ip6po_pktinfo) optdata = (void *)pktopt->ip6po_pktinfo; else { /* XXX: we don't have to do this every time... */ bzero(&null_pktinfo, sizeof(null_pktinfo)); optdata = (void *)&null_pktinfo; } optdatalen = sizeof(struct in6_pktinfo); break; case IPV6_TCLASS: if (pktopt && pktopt->ip6po_tclass >= 0) optdata = (void *)&pktopt->ip6po_tclass; else optdata = (void *)&deftclass; optdatalen = sizeof(int); break; case IPV6_HOPOPTS: if (pktopt && pktopt->ip6po_hbh) { optdata = (void *)pktopt->ip6po_hbh; ip6e = (struct ip6_ext *)pktopt->ip6po_hbh; optdatalen = (ip6e->ip6e_len + 1) << 3; } break; case IPV6_RTHDR: if (pktopt && pktopt->ip6po_rthdr) { optdata = (void *)pktopt->ip6po_rthdr; ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr; optdatalen = (ip6e->ip6e_len + 1) << 3; } break; case IPV6_RTHDRDSTOPTS: if (pktopt && pktopt->ip6po_dest1) { optdata = (void *)pktopt->ip6po_dest1; ip6e = (struct ip6_ext *)pktopt->ip6po_dest1; optdatalen = (ip6e->ip6e_len + 1) << 3; } break; case IPV6_DSTOPTS: if (pktopt && pktopt->ip6po_dest2) { optdata = (void *)pktopt->ip6po_dest2; ip6e = (struct ip6_ext *)pktopt->ip6po_dest2; optdatalen = (ip6e->ip6e_len + 1) << 3; } break; case IPV6_USE_MIN_MTU: if (pktopt) optdata = (void *)&pktopt->ip6po_minmtu; else optdata = (void *)&defminmtu; optdatalen = sizeof(int); break; case IPV6_DONTFRAG: if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG)) on = 1; else on = 0; optdata = (void *)&on; optdatalen = sizeof(on); break; default: /* should not happen */ #ifdef DIAGNOSTIC panic("%s: unexpected option", __func__); #endif return (ENOPROTOOPT); } if (optdatalen > MCLBYTES) return (EMSGSIZE); /* XXX */ if (optdatalen > MLEN) MCLGET(m, M_WAIT); m->m_len = optdatalen; if (optdatalen) bcopy(optdata, mtod(m, void *), optdatalen); return (error); } void ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname) { if (optname == -1 || optname == IPV6_PKTINFO) { if (pktopt->ip6po_pktinfo) free(pktopt->ip6po_pktinfo, M_IP6OPT, 0); pktopt->ip6po_pktinfo = NULL; } if (optname == -1 || optname == IPV6_HOPLIMIT) pktopt->ip6po_hlim = -1; if (optname == -1 || optname == IPV6_TCLASS) pktopt->ip6po_tclass = -1; if (optname == -1 || optname == IPV6_HOPOPTS) { if (pktopt->ip6po_hbh) free(pktopt->ip6po_hbh, M_IP6OPT, 0); pktopt->ip6po_hbh = NULL; } if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) { if (pktopt->ip6po_dest1) free(pktopt->ip6po_dest1, M_IP6OPT, 0); pktopt->ip6po_dest1 = NULL; } if (optname == -1 || optname == IPV6_RTHDR) { if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr) free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT, 0); pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL; if (pktopt->ip6po_route.ro_rt) { rtfree(pktopt->ip6po_route.ro_rt); pktopt->ip6po_route.ro_rt = NULL; } } if (optname == -1 || optname == IPV6_DSTOPTS) { if (pktopt->ip6po_dest2) free(pktopt->ip6po_dest2, M_IP6OPT, 0); pktopt->ip6po_dest2 = NULL; } } #define PKTOPT_EXTHDRCPY(type) \ do {\ if (src->type) {\ size_t hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\ dst->type = malloc(hlen, M_IP6OPT, M_NOWAIT);\ if (dst->type == NULL)\ goto bad;\ memcpy(dst->type, src->type, hlen);\ }\ } while (/*CONSTCOND*/ 0) int copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src) { dst->ip6po_hlim = src->ip6po_hlim; dst->ip6po_tclass = src->ip6po_tclass; dst->ip6po_flags = src->ip6po_flags; if (src->ip6po_pktinfo) { dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo), M_IP6OPT, M_NOWAIT); if (dst->ip6po_pktinfo == NULL) goto bad; *dst->ip6po_pktinfo = *src->ip6po_pktinfo; } PKTOPT_EXTHDRCPY(ip6po_hbh); PKTOPT_EXTHDRCPY(ip6po_dest1); PKTOPT_EXTHDRCPY(ip6po_dest2); PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */ return (0); bad: ip6_clearpktopts(dst, -1); return (ENOBUFS); } #undef PKTOPT_EXTHDRCPY void ip6_freepcbopts(struct ip6_pktopts *pktopt) { if (pktopt == NULL) return; ip6_clearpktopts(pktopt, -1); free(pktopt, M_IP6OPT, 0); } /* * Set the IP6 multicast options in response to user setsockopt(). */ int ip6_setmoptions(int optname, struct ip6_moptions **im6op, struct mbuf *m, unsigned int rtableid) { int error = 0; u_int loop, ifindex; struct ipv6_mreq *mreq; struct ifnet *ifp; struct ip6_moptions *im6o = *im6op; struct in6_multi_mship *imm; struct proc *p = curproc; /* XXX */ if (im6o == NULL) { /* * No multicast option buffer attached to the pcb; * allocate one and initialize to default values. */ im6o = malloc(sizeof(*im6o), M_IPMOPTS, M_WAITOK); if (im6o == NULL) return (ENOBUFS); *im6op = im6o; im6o->im6o_ifidx = 0; im6o->im6o_hlim = ip6_defmcasthlim; im6o->im6o_loop = IPV6_DEFAULT_MULTICAST_LOOP; LIST_INIT(&im6o->im6o_memberships); } switch (optname) { case IPV6_MULTICAST_IF: /* * Select the interface for outgoing multicast packets. */ if (m == NULL || m->m_len != sizeof(u_int)) { error = EINVAL; break; } memcpy(&ifindex, mtod(m, u_int *), sizeof(ifindex)); if (ifindex != 0) { ifp = if_get(ifindex); if (ifp == NULL) { error = ENXIO; /* XXX EINVAL? */ break; } if ((ifp->if_flags & IFF_MULTICAST) == 0) { error = EADDRNOTAVAIL; if_put(ifp); break; } if_put(ifp); } im6o->im6o_ifidx = ifindex; break; case IPV6_MULTICAST_HOPS: { /* * Set the IP6 hoplimit for outgoing multicast packets. */ int optval; if (m == NULL || m->m_len != sizeof(int)) { error = EINVAL; break; } memcpy(&optval, mtod(m, u_int *), sizeof(optval)); if (optval < -1 || optval >= 256) error = EINVAL; else if (optval == -1) im6o->im6o_hlim = ip6_defmcasthlim; else im6o->im6o_hlim = optval; break; } case IPV6_MULTICAST_LOOP: /* * Set the loopback flag for outgoing multicast packets. * Must be zero or one. */ if (m == NULL || m->m_len != sizeof(u_int)) { error = EINVAL; break; } memcpy(&loop, mtod(m, u_int *), sizeof(loop)); if (loop > 1) { error = EINVAL; break; } im6o->im6o_loop = loop; break; case IPV6_JOIN_GROUP: /* * Add a multicast group membership. * Group must be a valid IP6 multicast address. */ if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) { error = EINVAL; break; } mreq = mtod(m, struct ipv6_mreq *); if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) { /* * We use the unspecified address to specify to accept * all multicast addresses. Only super user is allowed * to do this. */ if (suser(p)) { error = EACCES; break; } } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) { error = EINVAL; break; } /* * If no interface was explicitly specified, choose an * appropriate one according to the given multicast address. */ if (mreq->ipv6mr_interface == 0) { struct rtentry *rt; struct sockaddr_in6 dst; memset(&dst, 0, sizeof(dst)); dst.sin6_len = sizeof(dst); dst.sin6_family = AF_INET6; dst.sin6_addr = mreq->ipv6mr_multiaddr; rt = rtalloc(sin6tosa(&dst), RT_RESOLVE, rtableid); if (rt == NULL) { error = EADDRNOTAVAIL; break; } ifp = if_get(rt->rt_ifidx); rtfree(rt); } else { /* * If the interface is specified, validate it. */ ifp = if_get(mreq->ipv6mr_interface); if (ifp == NULL) { error = ENXIO; /* XXX EINVAL? */ break; } } /* * See if we found an interface, and confirm that it * supports multicast */ if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { if_put(ifp); error = EADDRNOTAVAIL; break; } /* * Put interface index into the multicast address, * if the address has link/interface-local scope. */ if (IN6_IS_SCOPE_EMBED(&mreq->ipv6mr_multiaddr)) { mreq->ipv6mr_multiaddr.s6_addr16[1] = htons(ifp->if_index); } /* * See if the membership already exists. */ LIST_FOREACH(imm, &im6o->im6o_memberships, i6mm_chain) if (imm->i6mm_maddr->in6m_ifidx == ifp->if_index && IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr, &mreq->ipv6mr_multiaddr)) break; if (imm != NULL) { if_put(ifp); error = EADDRINUSE; break; } /* * Everything looks good; add a new record to the multicast * address list for the given interface. */ imm = in6_joingroup(ifp, &mreq->ipv6mr_multiaddr, &error); if_put(ifp); if (!imm) break; LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain); break; case IPV6_LEAVE_GROUP: /* * Drop a multicast group membership. * Group must be a valid IP6 multicast address. */ if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) { error = EINVAL; break; } mreq = mtod(m, struct ipv6_mreq *); if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) { if (suser(p)) { error = EACCES; break; } } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) { error = EINVAL; break; } /* * Put interface index into the multicast address, * if the address has link-local scope. */ if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) { mreq->ipv6mr_multiaddr.s6_addr16[1] = htons(mreq->ipv6mr_interface); } /* * If an interface address was specified, get a pointer * to its ifnet structure. */ if (mreq->ipv6mr_interface == 0) ifp = NULL; else { ifp = if_get(mreq->ipv6mr_interface); if (ifp == NULL) { error = ENXIO; /* XXX EINVAL? */ break; } } /* * Find the membership in the membership list. */ LIST_FOREACH(imm, &im6o->im6o_memberships, i6mm_chain) { if ((ifp == NULL || imm->i6mm_maddr->in6m_ifidx == ifp->if_index) && IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr, &mreq->ipv6mr_multiaddr)) break; } if_put(ifp); if (imm == NULL) { /* Unable to resolve interface */ error = EADDRNOTAVAIL; break; } /* * Give up the multicast address record to which the * membership points. */ LIST_REMOVE(imm, i6mm_chain); in6_leavegroup(imm); break; default: error = EOPNOTSUPP; break; } /* * If all options have default values, no need to keep the option * structure. */ if (im6o->im6o_ifidx == 0 && im6o->im6o_hlim == ip6_defmcasthlim && im6o->im6o_loop == IPV6_DEFAULT_MULTICAST_LOOP && LIST_EMPTY(&im6o->im6o_memberships)) { free(*im6op, M_IPMOPTS, sizeof(**im6op)); *im6op = NULL; } return (error); } /* * Return the IP6 multicast options in response to user getsockopt(). */ int ip6_getmoptions(int optname, struct ip6_moptions *im6o, struct mbuf *m) { u_int *hlim, *loop, *ifindex; switch (optname) { case IPV6_MULTICAST_IF: ifindex = mtod(m, u_int *); m->m_len = sizeof(u_int); if (im6o == NULL || im6o->im6o_ifidx == 0) *ifindex = 0; else *ifindex = im6o->im6o_ifidx; return (0); case IPV6_MULTICAST_HOPS: hlim = mtod(m, u_int *); m->m_len = sizeof(u_int); if (im6o == NULL) *hlim = ip6_defmcasthlim; else *hlim = im6o->im6o_hlim; return (0); case IPV6_MULTICAST_LOOP: loop = mtod(m, u_int *); m->m_len = sizeof(u_int); if (im6o == NULL) *loop = ip6_defmcasthlim; else *loop = im6o->im6o_loop; return (0); default: return (EOPNOTSUPP); } } /* * Discard the IP6 multicast options. */ void ip6_freemoptions(struct ip6_moptions *im6o) { struct in6_multi_mship *imm; if (im6o == NULL) return; while (!LIST_EMPTY(&im6o->im6o_memberships)) { imm = LIST_FIRST(&im6o->im6o_memberships); LIST_REMOVE(imm, i6mm_chain); in6_leavegroup(imm); } free(im6o, M_IPMOPTS, sizeof(*im6o)); } /* * Set IPv6 outgoing packet options based on advanced API. */ int ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt, struct ip6_pktopts *stickyopt, int priv, int uproto) { u_int clen; struct cmsghdr *cm = 0; caddr_t cmsgs; int error; if (control == NULL || opt == NULL) return (EINVAL); ip6_initpktopts(opt); if (stickyopt) { int error; /* * If stickyopt is provided, make a local copy of the options * for this particular packet, then override them by ancillary * objects. * XXX: copypktopts() does not copy the cached route to a next * hop (if any). This is not very good in terms of efficiency, * but we can allow this since this option should be rarely * used. */ if ((error = copypktopts(opt, stickyopt)) != 0) return (error); } /* * XXX: Currently, we assume all the optional information is stored * in a single mbuf. */ if (control->m_next) return (EINVAL); clen = control->m_len; cmsgs = mtod(control, caddr_t); do { if (clen < CMSG_LEN(0)) return (EINVAL); cm = (struct cmsghdr *)cmsgs; if (cm->cmsg_len < CMSG_LEN(0) || cm->cmsg_len > clen || CMSG_ALIGN(cm->cmsg_len) > clen) return (EINVAL); if (cm->cmsg_level == IPPROTO_IPV6) { error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm), cm->cmsg_len - CMSG_LEN(0), opt, priv, 0, uproto); if (error) return (error); } clen -= CMSG_ALIGN(cm->cmsg_len); cmsgs += CMSG_ALIGN(cm->cmsg_len); } while (clen); return (0); } /* * Set a particular packet option, as a sticky option or an ancillary data * item. "len" can be 0 only when it's a sticky option. */ int ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt, int priv, int sticky, int uproto) { int minmtupolicy; switch (optname) { case IPV6_PKTINFO: { struct ifnet *ifp = NULL; struct in6_pktinfo *pktinfo; if (len != sizeof(struct in6_pktinfo)) return (EINVAL); pktinfo = (struct in6_pktinfo *)buf; /* * An application can clear any sticky IPV6_PKTINFO option by * doing a "regular" setsockopt with ipi6_addr being * in6addr_any and ipi6_ifindex being zero. * [RFC 3542, Section 6] */ if (opt->ip6po_pktinfo && pktinfo->ipi6_ifindex == 0 && IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { ip6_clearpktopts(opt, optname); break; } if (uproto == IPPROTO_TCP && sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { return (EINVAL); } if (pktinfo->ipi6_ifindex) { ifp = if_get(pktinfo->ipi6_ifindex); if (ifp == NULL) return (ENXIO); if_put(ifp); } /* * We store the address anyway, and let in6_selectsrc() * validate the specified address. This is because ipi6_addr * may not have enough information about its scope zone, and * we may need additional information (such as outgoing * interface or the scope zone of a destination address) to * disambiguate the scope. * XXX: the delay of the validation may confuse the * application when it is used as a sticky option. */ if (opt->ip6po_pktinfo == NULL) { opt->ip6po_pktinfo = malloc(sizeof(*pktinfo), M_IP6OPT, M_NOWAIT); if (opt->ip6po_pktinfo == NULL) return (ENOBUFS); } bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo)); break; } case IPV6_HOPLIMIT: { int *hlimp; /* * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT * to simplify the ordering among hoplimit options. */ if (sticky) return (ENOPROTOOPT); if (len != sizeof(int)) return (EINVAL); hlimp = (int *)buf; if (*hlimp < -1 || *hlimp > 255) return (EINVAL); opt->ip6po_hlim = *hlimp; break; } case IPV6_TCLASS: { int tclass; if (len != sizeof(int)) return (EINVAL); tclass = *(int *)buf; if (tclass < -1 || tclass > 255) return (EINVAL); opt->ip6po_tclass = tclass; break; } case IPV6_HOPOPTS: { struct ip6_hbh *hbh; int hbhlen; /* * XXX: We don't allow a non-privileged user to set ANY HbH * options, since per-option restriction has too much * overhead. */ if (!priv) return (EPERM); if (len == 0) { ip6_clearpktopts(opt, IPV6_HOPOPTS); break; /* just remove the option */ } /* message length validation */ if (len < sizeof(struct ip6_hbh)) return (EINVAL); hbh = (struct ip6_hbh *)buf; hbhlen = (hbh->ip6h_len + 1) << 3; if (len != hbhlen) return (EINVAL); /* turn off the previous option, then set the new option. */ ip6_clearpktopts(opt, IPV6_HOPOPTS); opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT); if (opt->ip6po_hbh == NULL) return (ENOBUFS); memcpy(opt->ip6po_hbh, hbh, hbhlen); break; } case IPV6_DSTOPTS: case IPV6_RTHDRDSTOPTS: { struct ip6_dest *dest, **newdest = NULL; int destlen; if (!priv) /* XXX: see the comment for IPV6_HOPOPTS */ return (EPERM); if (len == 0) { ip6_clearpktopts(opt, optname); break; /* just remove the option */ } /* message length validation */ if (len < sizeof(struct ip6_dest)) return (EINVAL); dest = (struct ip6_dest *)buf; destlen = (dest->ip6d_len + 1) << 3; if (len != destlen) return (EINVAL); /* * Determine the position that the destination options header * should be inserted; before or after the routing header. */ switch (optname) { case IPV6_RTHDRDSTOPTS: newdest = &opt->ip6po_dest1; break; case IPV6_DSTOPTS: newdest = &opt->ip6po_dest2; break; } /* turn off the previous option, then set the new option. */ ip6_clearpktopts(opt, optname); *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT); if (*newdest == NULL) return (ENOBUFS); memcpy(*newdest, dest, destlen); break; } case IPV6_RTHDR: { struct ip6_rthdr *rth; int rthlen; if (len == 0) { ip6_clearpktopts(opt, IPV6_RTHDR); break; /* just remove the option */ } /* message length validation */ if (len < sizeof(struct ip6_rthdr)) return (EINVAL); rth = (struct ip6_rthdr *)buf; rthlen = (rth->ip6r_len + 1) << 3; if (len != rthlen) return (EINVAL); switch (rth->ip6r_type) { case IPV6_RTHDR_TYPE_0: if (rth->ip6r_len == 0) /* must contain one addr */ return (EINVAL); if (rth->ip6r_len % 2) /* length must be even */ return (EINVAL); if (rth->ip6r_len / 2 != rth->ip6r_segleft) return (EINVAL); break; default: return (EINVAL); /* not supported */ } /* turn off the previous option */ ip6_clearpktopts(opt, IPV6_RTHDR); opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT); if (opt->ip6po_rthdr == NULL) return (ENOBUFS); memcpy(opt->ip6po_rthdr, rth, rthlen); break; } case IPV6_USE_MIN_MTU: if (len != sizeof(int)) return (EINVAL); minmtupolicy = *(int *)buf; if (minmtupolicy != IP6PO_MINMTU_MCASTONLY && minmtupolicy != IP6PO_MINMTU_DISABLE && minmtupolicy != IP6PO_MINMTU_ALL) { return (EINVAL); } opt->ip6po_minmtu = minmtupolicy; break; case IPV6_DONTFRAG: if (len != sizeof(int)) return (EINVAL); if (uproto == IPPROTO_TCP || *(int *)buf == 0) { /* * we ignore this option for TCP sockets. * (RFC3542 leaves this case unspecified.) */ opt->ip6po_flags &= ~IP6PO_DONTFRAG; } else opt->ip6po_flags |= IP6PO_DONTFRAG; break; default: return (ENOPROTOOPT); } /* end of switch */ return (0); } /* * Routine called from ip6_output() to loop back a copy of an IP6 multicast * packet to the input queue of a specified interface. */ void ip6_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in6 *dst) { struct mbuf *copym; struct ip6_hdr *ip6; /* * Duplicate the packet. */ copym = m_copym(m, 0, M_COPYALL, M_NOWAIT); if (copym == NULL) return; /* * Make sure to deep-copy IPv6 header portion in case the data * is in an mbuf cluster, so that we can safely override the IPv6 * header portion later. */ if ((copym->m_flags & M_EXT) != 0 || copym->m_len < sizeof(struct ip6_hdr)) { copym = m_pullup(copym, sizeof(struct ip6_hdr)); if (copym == NULL) return; } #ifdef DIAGNOSTIC if (copym->m_len < sizeof(*ip6)) { m_freem(copym); return; } #endif ip6 = mtod(copym, struct ip6_hdr *); if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) ip6->ip6_src.s6_addr16[1] = 0; if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) ip6->ip6_dst.s6_addr16[1] = 0; if_input_local(ifp, copym, dst->sin6_family); } /* * Chop IPv6 header off from the payload. */ int ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs) { struct mbuf *mh; struct ip6_hdr *ip6; ip6 = mtod(m, struct ip6_hdr *); if (m->m_len > sizeof(*ip6)) { MGET(mh, M_DONTWAIT, MT_HEADER); if (mh == NULL) { m_freem(m); return ENOBUFS; } M_MOVE_PKTHDR(mh, m); m_align(mh, sizeof(*ip6)); m->m_len -= sizeof(*ip6); m->m_data += sizeof(*ip6); mh->m_next = m; m = mh; m->m_len = sizeof(*ip6); bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6)); } exthdrs->ip6e_ip6 = m; return 0; } u_int32_t ip6_randomid(void) { return idgen32(&ip6_id_ctx); } void ip6_randomid_init(void) { idgen32_init(&ip6_id_ctx); } /* * Compute significant parts of the IPv6 checksum pseudo-header * for use in a delayed TCP/UDP checksum calculation. */ static __inline u_int16_t __attribute__((__unused__)) in6_cksum_phdr(const struct in6_addr *src, const struct in6_addr *dst, u_int32_t len, u_int32_t nxt) { u_int32_t sum = 0; const u_int16_t *w; w = (const u_int16_t *) src; sum += w[0]; if (!IN6_IS_SCOPE_EMBED(src)) sum += w[1]; sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5]; sum += w[6]; sum += w[7]; w = (const u_int16_t *) dst; sum += w[0]; if (!IN6_IS_SCOPE_EMBED(dst)) sum += w[1]; sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5]; sum += w[6]; sum += w[7]; sum += (u_int16_t)(len >> 16) + (u_int16_t)(len /*& 0xffff*/); sum += (u_int16_t)(nxt >> 16) + (u_int16_t)(nxt /*& 0xffff*/); sum = (u_int16_t)(sum >> 16) + (u_int16_t)(sum /*& 0xffff*/); if (sum > 0xffff) sum -= 0xffff; return (sum); } /* * Process a delayed payload checksum calculation. */ void in6_delayed_cksum(struct mbuf *m, u_int8_t nxt) { int nxtp, offset; u_int16_t csum; offset = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxtp); if (offset <= 0 || nxtp != nxt) /* If the desired next protocol isn't found, punt. */ return; csum = (u_int16_t)(in6_cksum(m, 0, offset, m->m_pkthdr.len - offset)); switch (nxt) { case IPPROTO_TCP: offset += offsetof(struct tcphdr, th_sum); break; case IPPROTO_UDP: offset += offsetof(struct udphdr, uh_sum); if (csum == 0) csum = 0xffff; break; case IPPROTO_ICMPV6: offset += offsetof(struct icmp6_hdr, icmp6_cksum); break; } if ((offset + sizeof(u_int16_t)) > m->m_len) m_copyback(m, offset, sizeof(csum), &csum, M_NOWAIT); else *(u_int16_t *)(mtod(m, caddr_t) + offset) = csum; } void in6_proto_cksum_out(struct mbuf *m, struct ifnet *ifp) { struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); /* some hw and in6_delayed_cksum need the pseudo header cksum */ if (m->m_pkthdr.csum_flags & (M_TCP_CSUM_OUT|M_UDP_CSUM_OUT|M_ICMP_CSUM_OUT)) { int nxt, offset; u_int16_t csum; offset = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); csum = in6_cksum_phdr(&ip6->ip6_src, &ip6->ip6_dst, htonl(m->m_pkthdr.len - offset), htonl(nxt)); if (nxt == IPPROTO_TCP) offset += offsetof(struct tcphdr, th_sum); else if (nxt == IPPROTO_UDP) offset += offsetof(struct udphdr, uh_sum); else if (nxt == IPPROTO_ICMPV6) offset += offsetof(struct icmp6_hdr, icmp6_cksum); if ((offset + sizeof(u_int16_t)) > m->m_len) m_copyback(m, offset, sizeof(csum), &csum, M_NOWAIT); else *(u_int16_t *)(mtod(m, caddr_t) + offset) = csum; } if (m->m_pkthdr.csum_flags & M_TCP_CSUM_OUT) { if (!ifp || !(ifp->if_capabilities & IFCAP_CSUM_TCPv6) || ip6->ip6_nxt != IPPROTO_TCP || ifp->if_bridgeidx != 0) { tcpstat_inc(tcps_outswcsum); in6_delayed_cksum(m, IPPROTO_TCP); m->m_pkthdr.csum_flags &= ~M_TCP_CSUM_OUT; /* Clear */ } } else if (m->m_pkthdr.csum_flags & M_UDP_CSUM_OUT) { if (!ifp || !(ifp->if_capabilities & IFCAP_CSUM_UDPv6) || ip6->ip6_nxt != IPPROTO_UDP || ifp->if_bridgeidx != 0) { udpstat_inc(udps_outswcsum); in6_delayed_cksum(m, IPPROTO_UDP); m->m_pkthdr.csum_flags &= ~M_UDP_CSUM_OUT; /* Clear */ } } else if (m->m_pkthdr.csum_flags & M_ICMP_CSUM_OUT) { in6_delayed_cksum(m, IPPROTO_ICMPV6); m->m_pkthdr.csum_flags &= ~M_ICMP_CSUM_OUT; /* Clear */ } } #ifdef IPSEC struct tdb * ip6_output_ipsec_lookup(struct mbuf *m, int *error, struct inpcb *inp) { struct tdb *tdb; struct m_tag *mtag; struct tdb_ident *tdbi; /* * Check if there was an outgoing SA bound to the flow * from a transport protocol. */ /* Do we have any pending SAs to apply ? */ tdb = ipsp_spd_lookup(m, AF_INET6, sizeof(struct ip6_hdr), error, IPSP_DIRECTION_OUT, NULL, inp, 0); if (tdb == NULL) return NULL; /* Loop detection */ for (mtag = m_tag_first(m); mtag != NULL; mtag = m_tag_next(m, mtag)) { if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE) continue; tdbi = (struct tdb_ident *)(mtag + 1); if (tdbi->spi == tdb->tdb_spi && tdbi->proto == tdb->tdb_sproto && tdbi->rdomain == tdb->tdb_rdomain && !memcmp(&tdbi->dst, &tdb->tdb_dst, sizeof(union sockaddr_union))) { /* no IPsec needed */ return NULL; } } return tdb; } int ip6_output_ipsec_send(struct tdb *tdb, struct mbuf *m, int tunalready, int fwd) { #if NPF > 0 struct ifnet *encif; #endif int error; #if NPF > 0 if ((encif = enc_getif(tdb->tdb_rdomain, tdb->tdb_tap)) == NULL || pf_test(AF_INET6, fwd ? PF_FWD : PF_OUT, encif, &m) != PF_PASS) { m_freem(m); return EHOSTUNREACH; } if (m == NULL) return 0; /* * PF_TAG_REROUTE handling or not... * Packet is entering IPsec so the routing is * already overruled by the IPsec policy. * Until now the change was not reconsidered. * What's the behaviour? */ in6_proto_cksum_out(m, encif); #endif m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */ /* Callee frees mbuf */ error = ipsp_process_packet(m, tdb, AF_INET6, tunalready); if (error) { ipsecstat_inc(ipsec_odrops); tdb->tdb_odrops++; } return error; } #endif /* IPSEC */