sys/netinet/ip_output.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1982, 1986, 1988, 1990, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      @(#)ip_output.c 8.3 (Berkeley) 1/21/94
  32  */
  33
  34 #include <sys/cdefs.h>
  35 __FBSDID("$FreeBSD$");
  36
  37 #include "opt_inet.h"
  38 #include "opt_ratelimit.h"
  39 #include "opt_ipsec.h"
  40 #include "opt_mbuf_stress_test.h"
  41 #include "opt_mpath.h"
  42 #include "opt_route.h"
  43 #include "opt_sctp.h"
  44 #include "opt_rss.h"
  45
  46 #include <sys/param.h>
  47 #include <sys/systm.h>
  48 #include <sys/kernel.h>
  49 #include <sys/lock.h>
  50 #include <sys/malloc.h>
  51 #include <sys/mbuf.h>
  52 #include <sys/priv.h>
  53 #include <sys/proc.h>
  54 #include <sys/protosw.h>
  55 #include <sys/rmlock.h>
  56 #include <sys/sdt.h>
  57 #include <sys/socket.h>
  58 #include <sys/socketvar.h>
  59 #include <sys/sysctl.h>
  60 #include <sys/ucred.h>
  61
  62 #include <net/if.h>
  63 #include <net/if_var.h>
  64 #include <net/if_llatbl.h>
  65 #include <net/netisr.h>
  66 #include <net/pfil.h>
  67 #include <net/route.h>
  68 #ifdef RADIX_MPATH
  69 #include <net/radix_mpath.h>
  70 #endif
  71 #include <net/rss_config.h>
  72 #include <net/vnet.h>
  73
  74 #include <netinet/in.h>
  75 #include <netinet/in_kdtrace.h>
  76 #include <netinet/in_systm.h>
  77 #include <netinet/ip.h>
  78 #include <netinet/in_pcb.h>
  79 #include <netinet/in_rss.h>
  80 #include <netinet/in_var.h>
  81 #include <netinet/ip_var.h>
  82 #include <netinet/ip_options.h>
  83 #ifdef SCTP
  84 #include <netinet/sctp.h>
  85 #include <netinet/sctp_crc32.h>
  86 #endif
  87
  88 #include <netipsec/ipsec_support.h>
  89
  90 #include <machine/in_cksum.h>
  91
  92 #include <security/mac/mac_framework.h>
  93
  94 #ifdef MBUF_STRESS_TEST
  95 static int mbuf_frag_size = 0;
  96 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
  97         &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
  98 #endif
  99
 100 static void     ip_mloopback(struct ifnet *, const struct mbuf *, int);
 101
 102
 103 extern int in_mcast_loop;
 104 extern  struct protosw inetsw[];
 105
 106 static inline int
 107 ip_output_pfil(struct mbuf **mp, struct ifnet *ifp, struct inpcb *inp,
 108     struct sockaddr_in *dst, int *fibnum, int *error)
 109 {
 110         struct m_tag *fwd_tag = NULL;
 111         struct mbuf *m;
 112         struct in_addr odst;
 113         struct ip *ip;
 114
 115         m = *mp;
 116         ip = mtod(m, struct ip *);
 117
 118         /* Run through list of hooks for output packets. */
 119         odst.s_addr = ip->ip_dst.s_addr;
 120         *error = pfil_run_hooks(&V_inet_pfil_hook, mp, ifp, PFIL_OUT, inp);
 121         m = *mp;
 122         if ((*error) != 0 || m == NULL)
 123                 return 1; /* Finished */
 124
 125         ip = mtod(m, struct ip *);
 126
 127         /* See if destination IP address was changed by packet filter. */
 128         if (odst.s_addr != ip->ip_dst.s_addr) {
 129                 m->m_flags |= M_SKIP_FIREWALL;
 130                 /* If destination is now ourself drop to ip_input(). */
 131                 if (in_localip(ip->ip_dst)) {
 132                         m->m_flags |= M_FASTFWD_OURS;
 133                         if (m->m_pkthdr.rcvif == NULL)
 134                                 m->m_pkthdr.rcvif = V_loif;
 135                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 136                                 m->m_pkthdr.csum_flags |=
 137                                         CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
 138                                 m->m_pkthdr.csum_data = 0xffff;
 139                         }
 140                         m->m_pkthdr.csum_flags |=
 141                                 CSUM_IP_CHECKED | CSUM_IP_VALID;
 142 #ifdef SCTP
 143                         if (m->m_pkthdr.csum_flags & CSUM_SCTP)
 144                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 145 #endif
 146                         *error = netisr_queue(NETISR_IP, m);
 147                         return 1; /* Finished */
 148                 }
 149
 150                 bzero(dst, sizeof(*dst));
 151                 dst->sin_family = AF_INET;
 152                 dst->sin_len = sizeof(*dst);
 153                 dst->sin_addr = ip->ip_dst;
 154
 155                 return -1; /* Reloop */
 156         }
 157         /* See if fib was changed by packet filter. */
 158         if ((*fibnum) != M_GETFIB(m)) {
 159                 m->m_flags |= M_SKIP_FIREWALL;
 160                 *fibnum = M_GETFIB(m);
 161                 return -1; /* Reloop for FIB change */
 162         }
 163
 164         /* See if local, if yes, send it to netisr with IP_FASTFWD_OURS. */
 165         if (m->m_flags & M_FASTFWD_OURS) {
 166                 if (m->m_pkthdr.rcvif == NULL)
 167                         m->m_pkthdr.rcvif = V_loif;
 168                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 169                         m->m_pkthdr.csum_flags |=
 170                                 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
 171                         m->m_pkthdr.csum_data = 0xffff;
 172                 }
 173 #ifdef SCTP
 174                 if (m->m_pkthdr.csum_flags & CSUM_SCTP)
 175                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 176 #endif
 177                 m->m_pkthdr.csum_flags |=
 178                         CSUM_IP_CHECKED | CSUM_IP_VALID;
 179
 180                 *error = netisr_queue(NETISR_IP, m);
 181                 return 1; /* Finished */
 182         }
 183         /* Or forward to some other address? */
 184         if ((m->m_flags & M_IP_NEXTHOP) &&
 185             ((fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL)) {
 186                 bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in));
 187                 m->m_flags |= M_SKIP_FIREWALL;
 188                 m->m_flags &= ~M_IP_NEXTHOP;
 189                 m_tag_delete(m, fwd_tag);
 190
 191                 return -1; /* Reloop for CHANGE of dst */
 192         }
 193
 194         return 0;
 195 }
 196
 197 /*
 198  * IP output.  The packet in mbuf chain m contains a skeletal IP
 199  * header (with len, off, ttl, proto, tos, src, dst).
 200  * The mbuf chain containing the packet will be freed.
 201  * The mbuf opt, if present, will not be freed.
 202  * If route ro is present and has ro_rt initialized, route lookup would be
 203  * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
 204  * then result of route lookup is stored in ro->ro_rt.
 205  *
 206  * In the IP forwarding case, the packet will arrive with options already
 207  * inserted, so must have a NULL opt pointer.
 208  */
 209 int
 210 ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
 211     struct ip_moptions *imo, struct inpcb *inp)
 212 {
 213         struct rm_priotracker in_ifa_tracker;
 214         struct ip *ip;
 215         struct ifnet *ifp = NULL;       /* keep compiler happy */
 216         struct mbuf *m0;
 217         int hlen = sizeof (struct ip);
 218         int mtu;
 219         int error = 0;
 220         struct sockaddr_in *dst;
 221         const struct sockaddr_in *gw;
 222         struct in_ifaddr *ia;
 223         int isbroadcast;
 224         uint16_t ip_len, ip_off;
 225         struct route iproute;
 226         struct rtentry *rte;    /* cache for ro->ro_rt */
 227         uint32_t fibnum;
 228         int have_ia_ref;
 229 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 230         int no_route_but_check_spd = 0;
 231 #endif
 232         M_ASSERTPKTHDR(m);
 233
 234         if (inp != NULL) {
 235                 INP_LOCK_ASSERT(inp);
 236                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 237                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 238                         m->m_pkthdr.flowid = inp->inp_flowid;
 239                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 240                 }
 241         }
 242
 243         if (ro == NULL) {
 244                 ro = &iproute;
 245                 bzero(ro, sizeof (*ro));
 246         }
 247
 248         if (opt) {
 249                 int len = 0;
 250                 m = ip_insertoptions(m, opt, &len);
 251                 if (len != 0)
 252                         hlen = len; /* ip->ip_hl is updated above */
 253         }
 254         ip = mtod(m, struct ip *);
 255         ip_len = ntohs(ip->ip_len);
 256         ip_off = ntohs(ip->ip_off);
 257
 258         if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) {
 259                 ip->ip_v = IPVERSION;
 260                 ip->ip_hl = hlen >> 2;
 261                 ip_fillid(ip);
 262                 IPSTAT_INC(ips_localout);
 263         } else {
 264                 /* Header already set, fetch hlen from there */
 265                 hlen = ip->ip_hl << 2;
 266         }
 267
 268         /*
 269          * dst/gw handling:
 270          *
 271          * dst can be rewritten but always points to &ro->ro_dst.
 272          * gw is readonly but can point either to dst OR rt_gateway,
 273          * therefore we need restore gw if we're redoing lookup.
 274          */
 275         gw = dst = (struct sockaddr_in *)&ro->ro_dst;
 276         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 277         rte = ro->ro_rt;
 278         if (rte == NULL) {
 279                 bzero(dst, sizeof(*dst));
 280                 dst->sin_family = AF_INET;
 281                 dst->sin_len = sizeof(*dst);
 282                 dst->sin_addr = ip->ip_dst;
 283         }
 284 again:
 285         /*
 286          * Validate route against routing table additions;
 287          * a better/more specific route might have been added.
 288          */
 289         if (inp)
 290                 RT_VALIDATE(ro, &inp->inp_rt_cookie, fibnum);
 291         /*
 292          * If there is a cached route,
 293          * check that it is to the same destination
 294          * and is still up.  If not, free it and try again.
 295          * The address family should also be checked in case of sharing the
 296          * cache with IPv6.
 297          * Also check whether routing cache needs invalidation.
 298          */
 299         rte = ro->ro_rt;
 300         if (rte && ((rte->rt_flags & RTF_UP) == 0 ||
 301                     rte->rt_ifp == NULL ||
 302                     !RT_LINK_IS_UP(rte->rt_ifp) ||
 303                           dst->sin_family != AF_INET ||
 304                           dst->sin_addr.s_addr != ip->ip_dst.s_addr)) {
 305                 RTFREE(rte);
 306                 rte = ro->ro_rt = (struct rtentry *)NULL;
 307                 if (ro->ro_lle)
 308                         LLE_FREE(ro->ro_lle);   /* zeros ro_lle */
 309                 ro->ro_lle = (struct llentry *)NULL;
 310         }
 311         ia = NULL;
 312         have_ia_ref = 0;
 313         /*
 314          * If routing to interface only, short circuit routing lookup.
 315          * The use of an all-ones broadcast address implies this; an
 316          * interface is specified by the broadcast address of an interface,
 317          * or the destination address of a ptp interface.
 318          */
 319         if (flags & IP_SENDONES) {
 320                 if ((ia = ifatoia(ifa_ifwithbroadaddr(sintosa(dst),
 321                                                       M_GETFIB(m)))) == NULL &&
 322                     (ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
 323                                                     M_GETFIB(m)))) == NULL) {
 324                         IPSTAT_INC(ips_noroute);
 325                         error = ENETUNREACH;
 326                         goto bad;
 327                 }
 328                 have_ia_ref = 1;
 329                 ip->ip_dst.s_addr = INADDR_BROADCAST;
 330                 dst->sin_addr = ip->ip_dst;
 331                 ifp = ia->ia_ifp;
 332                 ip->ip_ttl = 1;
 333                 isbroadcast = 1;
 334         } else if (flags & IP_ROUTETOIF) {
 335                 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
 336                                                     M_GETFIB(m)))) == NULL &&
 337                     (ia = ifatoia(ifa_ifwithnet(sintosa(dst), 0,
 338                                                 M_GETFIB(m)))) == NULL) {
 339                         IPSTAT_INC(ips_noroute);
 340                         error = ENETUNREACH;
 341                         goto bad;
 342                 }
 343                 have_ia_ref = 1;
 344                 ifp = ia->ia_ifp;
 345                 ip->ip_ttl = 1;
 346                 isbroadcast = ifp->if_flags & IFF_BROADCAST ?
 347                     in_ifaddr_broadcast(dst->sin_addr, ia) : 0;
 348         } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
 349             imo != NULL && imo->imo_multicast_ifp != NULL) {
 350                 /*
 351                  * Bypass the normal routing lookup for multicast
 352                  * packets if the interface is specified.
 353                  */
 354                 ifp = imo->imo_multicast_ifp;
 355                 IFP_TO_IA(ifp, ia, &in_ifa_tracker);
 356                 if (ia)
 357                         have_ia_ref = 1;
 358                 isbroadcast = 0;        /* fool gcc */
 359         } else {
 360                 /*
 361                  * We want to do any cloning requested by the link layer,
 362                  * as this is probably required in all cases for correct
 363                  * operation (as it is for ARP).
 364                  */
 365                 if (rte == NULL) {
 366 #ifdef RADIX_MPATH
 367                         rtalloc_mpath_fib(ro,
 368                             ntohl(ip->ip_src.s_addr ^ ip->ip_dst.s_addr),
 369                             fibnum);
 370 #else
 371                         in_rtalloc_ign(ro, 0, fibnum);
 372 #endif
 373                         rte = ro->ro_rt;
 374                 }
 375                 if (rte == NULL ||
 376                     (rte->rt_flags & RTF_UP) == 0 ||
 377                     rte->rt_ifp == NULL ||
 378                     !RT_LINK_IS_UP(rte->rt_ifp)) {
 379 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 380                         /*
 381                          * There is no route for this packet, but it is
 382                          * possible that a matching SPD entry exists.
 383                          */
 384                         no_route_but_check_spd = 1;
 385                         mtu = 0; /* Silence GCC warning. */
 386                         goto sendit;
 387 #endif
 388                         IPSTAT_INC(ips_noroute);
 389                         error = EHOSTUNREACH;
 390                         goto bad;
 391                 }
 392                 ia = ifatoia(rte->rt_ifa);
 393                 ifp = rte->rt_ifp;
 394                 counter_u64_add(rte->rt_pksent, 1);
 395                 rt_update_ro_flags(ro);
 396                 if (rte->rt_flags & RTF_GATEWAY)
 397                         gw = (struct sockaddr_in *)rte->rt_gateway;
 398                 if (rte->rt_flags & RTF_HOST)
 399                         isbroadcast = (rte->rt_flags & RTF_BROADCAST);
 400                 else if (ifp->if_flags & IFF_BROADCAST)
 401                         isbroadcast = in_ifaddr_broadcast(gw->sin_addr, ia);
 402                 else
 403                         isbroadcast = 0;
 404         }
 405
 406         /*
 407          * Calculate MTU.  If we have a route that is up, use that,
 408          * otherwise use the interface's MTU.
 409          */
 410         if (rte != NULL && (rte->rt_flags & (RTF_UP|RTF_HOST)))
 411                 mtu = rte->rt_mtu;
 412         else
 413                 mtu = ifp->if_mtu;
 414         /* Catch a possible divide by zero later. */
 415         KASSERT(mtu > 0, ("%s: mtu %d <= 0, rte=%p (rt_flags=0x%08x) ifp=%p",
 416             __func__, mtu, rte, (rte != NULL) ? rte->rt_flags : 0, ifp));
 417
 418         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
 419                 m->m_flags |= M_MCAST;
 420                 /*
 421                  * IP destination address is multicast.  Make sure "gw"
 422                  * still points to the address in "ro".  (It may have been
 423                  * changed to point to a gateway address, above.)
 424                  */
 425                 gw = dst;
 426                 /*
 427                  * See if the caller provided any multicast options
 428                  */
 429                 if (imo != NULL) {
 430                         ip->ip_ttl = imo->imo_multicast_ttl;
 431                         if (imo->imo_multicast_vif != -1)
 432                                 ip->ip_src.s_addr =
 433                                     ip_mcast_src ?
 434                                     ip_mcast_src(imo->imo_multicast_vif) :
 435                                     INADDR_ANY;
 436                 } else
 437                         ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
 438                 /*
 439                  * Confirm that the outgoing interface supports multicast.
 440                  */
 441                 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
 442                         if ((ifp->if_flags & IFF_MULTICAST) == 0) {
 443                                 IPSTAT_INC(ips_noroute);
 444                                 error = ENETUNREACH;
 445                                 goto bad;
 446                         }
 447                 }
 448                 /*
 449                  * If source address not specified yet, use address
 450                  * of outgoing interface.
 451                  */
 452                 if (ip->ip_src.s_addr == INADDR_ANY) {
 453                         /* Interface may have no addresses. */
 454                         if (ia != NULL)
 455                                 ip->ip_src = IA_SIN(ia)->sin_addr;
 456                 }
 457
 458                 if ((imo == NULL && in_mcast_loop) ||
 459                     (imo && imo->imo_multicast_loop)) {
 460                         /*
 461                          * Loop back multicast datagram if not expressly
 462                          * forbidden to do so, even if we are not a member
 463                          * of the group; ip_input() will filter it later,
 464                          * thus deferring a hash lookup and mutex acquisition
 465                          * at the expense of a cheap copy using m_copym().
 466                          */
 467                         ip_mloopback(ifp, m, hlen);
 468                 } else {
 469                         /*
 470                          * If we are acting as a multicast router, perform
 471                          * multicast forwarding as if the packet had just
 472                          * arrived on the interface to which we are about
 473                          * to send.  The multicast forwarding function
 474                          * recursively calls this function, using the
 475                          * IP_FORWARDING flag to prevent infinite recursion.
 476                          *
 477                          * Multicasts that are looped back by ip_mloopback(),
 478                          * above, will be forwarded by the ip_input() routine,
 479                          * if necessary.
 480                          */
 481                         if (V_ip_mrouter && (flags & IP_FORWARDING) == 0) {
 482                                 /*
 483                                  * If rsvp daemon is not running, do not
 484                                  * set ip_moptions. This ensures that the packet
 485                                  * is multicast and not just sent down one link
 486                                  * as prescribed by rsvpd.
 487                                  */
 488                                 if (!V_rsvp_on)
 489                                         imo = NULL;
 490                                 if (ip_mforward &&
 491                                     ip_mforward(ip, ifp, m, imo) != 0) {
 492                                         m_freem(m);
 493                                         goto done;
 494                                 }
 495                         }
 496                 }
 497
 498                 /*
 499                  * Multicasts with a time-to-live of zero may be looped-
 500                  * back, above, but must not be transmitted on a network.
 501                  * Also, multicasts addressed to the loopback interface
 502                  * are not sent -- the above call to ip_mloopback() will
 503                  * loop back a copy. ip_input() will drop the copy if
 504                  * this host does not belong to the destination group on
 505                  * the loopback interface.
 506                  */
 507                 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
 508                         m_freem(m);
 509                         goto done;
 510                 }
 511
 512                 goto sendit;
 513         }
 514
 515         /*
 516          * If the source address is not specified yet, use the address
 517          * of the outoing interface.
 518          */
 519         if (ip->ip_src.s_addr == INADDR_ANY) {
 520                 /* Interface may have no addresses. */
 521                 if (ia != NULL) {
 522                         ip->ip_src = IA_SIN(ia)->sin_addr;
 523                 }
 524         }
 525
 526         /*
 527          * Look for broadcast address and
 528          * verify user is allowed to send
 529          * such a packet.
 530          */
 531         if (isbroadcast) {
 532                 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
 533                         error = EADDRNOTAVAIL;
 534                         goto bad;
 535                 }
 536                 if ((flags & IP_ALLOWBROADCAST) == 0) {
 537                         error = EACCES;
 538                         goto bad;
 539                 }
 540                 /* don't allow broadcast messages to be fragmented */
 541                 if (ip_len > mtu) {
 542                         error = EMSGSIZE;
 543                         goto bad;
 544                 }
 545                 m->m_flags |= M_BCAST;
 546         } else {
 547                 m->m_flags &= ~M_BCAST;
 548         }
 549
 550 sendit:
 551 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 552         if (IPSEC_ENABLED(ipv4)) {
 553                 if ((error = IPSEC_OUTPUT(ipv4, m, inp)) != 0) {
 554                         if (error == EINPROGRESS)
 555                                 error = 0;
 556                         goto done;
 557                 }
 558         }
 559         /*
 560          * Check if there was a route for this packet; return error if not.
 561          */
 562         if (no_route_but_check_spd) {
 563                 IPSTAT_INC(ips_noroute);
 564                 error = EHOSTUNREACH;
 565                 goto bad;
 566         }
 567         /* Update variables that are affected by ipsec4_output(). */
 568         ip = mtod(m, struct ip *);
 569         hlen = ip->ip_hl << 2;
 570 #endif /* IPSEC */
 571
 572         /* Jump over all PFIL processing if hooks are not active. */
 573         if (PFIL_HOOKED(&V_inet_pfil_hook)) {
 574                 switch (ip_output_pfil(&m, ifp, inp, dst, &fibnum, &error)) {
 575                 case 1: /* Finished */
 576                         goto done;
 577
 578                 case 0: /* Continue normally */
 579                         ip = mtod(m, struct ip *);
 580                         break;
 581
 582                 case -1: /* Need to try again */
 583                         /* Reset everything for a new round */
 584                         RO_RTFREE(ro);
 585                         if (have_ia_ref)
 586                                 ifa_free(&ia->ia_ifa);
 587                         ro->ro_prepend = NULL;
 588                         rte = NULL;
 589                         gw = dst;
 590                         ip = mtod(m, struct ip *);
 591                         goto again;
 592
 593                 }
 594         }
 595
 596         /* 127/8 must not appear on wire - RFC1122. */
 597         if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
 598             (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
 599                 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
 600                         IPSTAT_INC(ips_badaddr);
 601                         error = EADDRNOTAVAIL;
 602                         goto bad;
 603                 }
 604         }
 605
 606         m->m_pkthdr.csum_flags |= CSUM_IP;
 607         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
 608                 in_delayed_cksum(m);
 609                 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
 610         }
 611 #ifdef SCTP
 612         if (m->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
 613                 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
 614                 m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
 615         }
 616 #endif
 617
 618         /*
 619          * If small enough for interface, or the interface will take
 620          * care of the fragmentation for us, we can just send directly.
 621          */
 622         if (ip_len <= mtu ||
 623             (m->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0) {
 624                 ip->ip_sum = 0;
 625                 if (m->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
 626                         ip->ip_sum = in_cksum(m, hlen);
 627                         m->m_pkthdr.csum_flags &= ~CSUM_IP;
 628                 }
 629
 630                 /*
 631                  * Record statistics for this interface address.
 632                  * With CSUM_TSO the byte/packet count will be slightly
 633                  * incorrect because we count the IP+TCP headers only
 634                  * once instead of for every generated packet.
 635                  */
 636                 if (!(flags & IP_FORWARDING) && ia) {
 637                         if (m->m_pkthdr.csum_flags & CSUM_TSO)
 638                                 counter_u64_add(ia->ia_ifa.ifa_opackets,
 639                                     m->m_pkthdr.len / m->m_pkthdr.tso_segsz);
 640                         else
 641                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
 642
 643                         counter_u64_add(ia->ia_ifa.ifa_obytes, m->m_pkthdr.len);
 644                 }
 645 #ifdef MBUF_STRESS_TEST
 646                 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size)
 647                         m = m_fragment(m, M_NOWAIT, mbuf_frag_size);
 648 #endif
 649                 /*
 650                  * Reset layer specific mbuf flags
 651                  * to avoid confusing lower layers.
 652                  */
 653                 m_clrprotoflags(m);
 654                 IP_PROBE(send, NULL, NULL, ip, ifp, ip, NULL);
 655 #ifdef RATELIMIT
 656                 if (inp != NULL) {
 657                         if (inp->inp_flags2 & INP_RATE_LIMIT_CHANGED)
 658                                 in_pcboutput_txrtlmt(inp, ifp, m);
 659                         /* stamp send tag on mbuf */
 660                         m->m_pkthdr.snd_tag = inp->inp_snd_tag;
 661                 } else {
 662                         m->m_pkthdr.snd_tag = NULL;
 663                 }
 664 #endif
 665                 error = (*ifp->if_output)(ifp, m,
 666                     (const struct sockaddr *)gw, ro);
 667 #ifdef RATELIMIT
 668                 /* check for route change */
 669                 if (error == EAGAIN)
 670                         in_pcboutput_eagain(inp);
 671 #endif
 672                 goto done;
 673         }
 674
 675         /* Balk when DF bit is set or the interface didn't support TSO. */
 676         if ((ip_off & IP_DF) || (m->m_pkthdr.csum_flags & CSUM_TSO)) {
 677                 error = EMSGSIZE;
 678                 IPSTAT_INC(ips_cantfrag);
 679                 goto bad;
 680         }
 681
 682         /*
 683          * Too large for interface; fragment if possible. If successful,
 684          * on return, m will point to a list of packets to be sent.
 685          */
 686         error = ip_fragment(ip, &m, mtu, ifp->if_hwassist);
 687         if (error)
 688                 goto bad;
 689         for (; m; m = m0) {
 690                 m0 = m->m_nextpkt;
 691                 m->m_nextpkt = 0;
 692                 if (error == 0) {
 693                         /* Record statistics for this interface address. */
 694                         if (ia != NULL) {
 695                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
 696                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
 697                                     m->m_pkthdr.len);
 698                         }
 699                         /*
 700                          * Reset layer specific mbuf flags
 701                          * to avoid confusing upper layers.
 702                          */
 703                         m_clrprotoflags(m);
 704
 705                         IP_PROBE(send, NULL, NULL, mtod(m, struct ip *), ifp,
 706                             mtod(m, struct ip *), NULL);
 707 #ifdef RATELIMIT
 708                         if (inp != NULL) {
 709                                 if (inp->inp_flags2 & INP_RATE_LIMIT_CHANGED)
 710                                         in_pcboutput_txrtlmt(inp, ifp, m);
 711                                 /* stamp send tag on mbuf */
 712                                 m->m_pkthdr.snd_tag = inp->inp_snd_tag;
 713                         } else {
 714                                 m->m_pkthdr.snd_tag = NULL;
 715                         }
 716 #endif
 717                         error = (*ifp->if_output)(ifp, m,
 718                             (const struct sockaddr *)gw, ro);
 719 #ifdef RATELIMIT
 720                         /* check for route change */
 721                         if (error == EAGAIN)
 722                                 in_pcboutput_eagain(inp);
 723 #endif
 724                 } else
 725                         m_freem(m);
 726         }
 727
 728         if (error == 0)
 729                 IPSTAT_INC(ips_fragmented);
 730
 731 done:
 732         if (ro == &iproute)
 733                 RO_RTFREE(ro);
 734         else if (rte == NULL)
 735                 /*
 736                  * If the caller supplied a route but somehow the reference
 737                  * to it has been released need to prevent the caller
 738                  * calling RTFREE on it again.
 739                  */
 740                 ro->ro_rt = NULL;
 741         if (have_ia_ref)
 742                 ifa_free(&ia->ia_ifa);
 743         return (error);
 744 bad:
 745         m_freem(m);
 746         goto done;
 747 }
 748
 749 /*
 750  * Create a chain of fragments which fit the given mtu. m_frag points to the
 751  * mbuf to be fragmented; on return it points to the chain with the fragments.
 752  * Return 0 if no error. If error, m_frag may contain a partially built
 753  * chain of fragments that should be freed by the caller.
 754  *
 755  * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
 756  */
 757 int
 758 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
 759     u_long if_hwassist_flags)
 760 {
 761         int error = 0;
 762         int hlen = ip->ip_hl << 2;
 763         int len = (mtu - hlen) & ~7;    /* size of payload in each fragment */
 764         int off;
 765         struct mbuf *m0 = *m_frag;      /* the original packet          */
 766         int firstlen;
 767         struct mbuf **mnext;
 768         int nfrags;
 769         uint16_t ip_len, ip_off;
 770
 771         ip_len = ntohs(ip->ip_len);
 772         ip_off = ntohs(ip->ip_off);
 773
 774         if (ip_off & IP_DF) {   /* Fragmentation not allowed */
 775                 IPSTAT_INC(ips_cantfrag);
 776                 return EMSGSIZE;
 777         }
 778
 779         /*
 780          * Must be able to put at least 8 bytes per fragment.
 781          */
 782         if (len < 8)
 783                 return EMSGSIZE;
 784
 785         /*
 786          * If the interface will not calculate checksums on
 787          * fragmented packets, then do it here.
 788          */
 789         if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 790                 in_delayed_cksum(m0);
 791                 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
 792         }
 793 #ifdef SCTP
 794         if (m0->m_pkthdr.csum_flags & CSUM_SCTP) {
 795                 sctp_delayed_cksum(m0, hlen);
 796                 m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
 797         }
 798 #endif
 799         if (len > PAGE_SIZE) {
 800                 /*
 801                  * Fragment large datagrams such that each segment
 802                  * contains a multiple of PAGE_SIZE amount of data,
 803                  * plus headers. This enables a receiver to perform
 804                  * page-flipping zero-copy optimizations.
 805                  *
 806                  * XXX When does this help given that sender and receiver
 807                  * could have different page sizes, and also mtu could
 808                  * be less than the receiver's page size ?
 809                  */
 810                 int newlen;
 811
 812                 off = MIN(mtu, m0->m_pkthdr.len);
 813
 814                 /*
 815                  * firstlen (off - hlen) must be aligned on an
 816                  * 8-byte boundary
 817                  */
 818                 if (off < hlen)
 819                         goto smart_frag_failure;
 820                 off = ((off - hlen) & ~7) + hlen;
 821                 newlen = (~PAGE_MASK) & mtu;
 822                 if ((newlen + sizeof (struct ip)) > mtu) {
 823                         /* we failed, go back the default */
 824 smart_frag_failure:
 825                         newlen = len;
 826                         off = hlen + len;
 827                 }
 828                 len = newlen;
 829
 830         } else {
 831                 off = hlen + len;
 832         }
 833
 834         firstlen = off - hlen;
 835         mnext = &m0->m_nextpkt;         /* pointer to next packet */
 836
 837         /*
 838          * Loop through length of segment after first fragment,
 839          * make new header and copy data of each part and link onto chain.
 840          * Here, m0 is the original packet, m is the fragment being created.
 841          * The fragments are linked off the m_nextpkt of the original
 842          * packet, which after processing serves as the first fragment.
 843          */
 844         for (nfrags = 1; off < ip_len; off += len, nfrags++) {
 845                 struct ip *mhip;        /* ip header on the fragment */
 846                 struct mbuf *m;
 847                 int mhlen = sizeof (struct ip);
 848
 849                 m = m_gethdr(M_NOWAIT, MT_DATA);
 850                 if (m == NULL) {
 851                         error = ENOBUFS;
 852                         IPSTAT_INC(ips_odropped);
 853                         goto done;
 854                 }
 855                 /*
 856                  * Make sure the complete packet header gets copied
 857                  * from the originating mbuf to the newly created
 858                  * mbuf. This also ensures that existing firewall
 859                  * classification(s), VLAN tags and so on get copied
 860                  * to the resulting fragmented packet(s):
 861                  */
 862                 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
 863                         m_free(m);
 864                         error = ENOBUFS;
 865                         IPSTAT_INC(ips_odropped);
 866                         goto done;
 867                 }
 868                 /*
 869                  * In the first mbuf, leave room for the link header, then
 870                  * copy the original IP header including options. The payload
 871                  * goes into an additional mbuf chain returned by m_copym().
 872                  */
 873                 m->m_data += max_linkhdr;
 874                 mhip = mtod(m, struct ip *);
 875                 *mhip = *ip;
 876                 if (hlen > sizeof (struct ip)) {
 877                         mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
 878                         mhip->ip_v = IPVERSION;
 879                         mhip->ip_hl = mhlen >> 2;
 880                 }
 881                 m->m_len = mhlen;
 882                 /* XXX do we need to add ip_off below ? */
 883                 mhip->ip_off = ((off - hlen) >> 3) + ip_off;
 884                 if (off + len >= ip_len)
 885                         len = ip_len - off;
 886                 else
 887                         mhip->ip_off |= IP_MF;
 888                 mhip->ip_len = htons((u_short)(len + mhlen));
 889                 m->m_next = m_copym(m0, off, len, M_NOWAIT);
 890                 if (m->m_next == NULL) {        /* copy failed */
 891                         m_free(m);
 892                         error = ENOBUFS;        /* ??? */
 893                         IPSTAT_INC(ips_odropped);
 894                         goto done;
 895                 }
 896                 m->m_pkthdr.len = mhlen + len;
 897 #ifdef MAC
 898                 mac_netinet_fragment(m0, m);
 899 #endif
 900                 mhip->ip_off = htons(mhip->ip_off);
 901                 mhip->ip_sum = 0;
 902                 if (m->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
 903                         mhip->ip_sum = in_cksum(m, mhlen);
 904                         m->m_pkthdr.csum_flags &= ~CSUM_IP;
 905                 }
 906                 *mnext = m;
 907                 mnext = &m->m_nextpkt;
 908         }
 909         IPSTAT_ADD(ips_ofragments, nfrags);
 910
 911         /*
 912          * Update first fragment by trimming what's been copied out
 913          * and updating header.
 914          */
 915         m_adj(m0, hlen + firstlen - ip_len);
 916         m0->m_pkthdr.len = hlen + firstlen;
 917         ip->ip_len = htons((u_short)m0->m_pkthdr.len);
 918         ip->ip_off = htons(ip_off | IP_MF);
 919         ip->ip_sum = 0;
 920         if (m0->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
 921                 ip->ip_sum = in_cksum(m0, hlen);
 922                 m0->m_pkthdr.csum_flags &= ~CSUM_IP;
 923         }
 924
 925 done:
 926         *m_frag = m0;
 927         return error;
 928 }
 929
 930 void
 931 in_delayed_cksum(struct mbuf *m)
 932 {
 933         struct ip *ip;
 934         uint16_t csum, offset, ip_len;
 935
 936         ip = mtod(m, struct ip *);
 937         offset = ip->ip_hl << 2 ;
 938         ip_len = ntohs(ip->ip_len);
 939         csum = in_cksum_skip(m, ip_len, offset);
 940         if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0)
 941                 csum = 0xffff;
 942         offset += m->m_pkthdr.csum_data;        /* checksum offset */
 943
 944         /* find the mbuf in the chain where the checksum starts*/
 945         while ((m != NULL) && (offset >= m->m_len)) {
 946                 offset -= m->m_len;
 947                 m = m->m_next;
 948         }
 949         KASSERT(m != NULL, ("in_delayed_cksum: checksum outside mbuf chain."));
 950         KASSERT(offset + sizeof(u_short) <= m->m_len, ("in_delayed_cksum: checksum split between mbufs."));
 951         *(u_short *)(m->m_data + offset) = csum;
 952 }
 953
 954 /*
 955  * IP socket option processing.
 956  */
 957 int
 958 ip_ctloutput(struct socket *so, struct sockopt *sopt)
 959 {
 960         struct  inpcb *inp = sotoinpcb(so);
 961         int     error, optval;
 962 #ifdef  RSS
 963         uint32_t rss_bucket;
 964         int retval;
 965 #endif
 966
 967         error = optval = 0;
 968         if (sopt->sopt_level != IPPROTO_IP) {
 969                 error = EINVAL;
 970
 971                 if (sopt->sopt_level == SOL_SOCKET &&
 972                     sopt->sopt_dir == SOPT_SET) {
 973                         switch (sopt->sopt_name) {
 974                         case SO_REUSEADDR:
 975                                 INP_WLOCK(inp);
 976                                 if ((so->so_options & SO_REUSEADDR) != 0)
 977                                         inp->inp_flags2 |= INP_REUSEADDR;
 978                                 else
 979                                         inp->inp_flags2 &= ~INP_REUSEADDR;
 980                                 INP_WUNLOCK(inp);
 981                                 error = 0;
 982                                 break;
 983                         case SO_REUSEPORT:
 984                                 INP_WLOCK(inp);
 985                                 if ((so->so_options & SO_REUSEPORT) != 0)
 986                                         inp->inp_flags2 |= INP_REUSEPORT;
 987                                 else
 988                                         inp->inp_flags2 &= ~INP_REUSEPORT;
 989                                 INP_WUNLOCK(inp);
 990                                 error = 0;
 991                                 break;
 992                         case SO_SETFIB:
 993                                 INP_WLOCK(inp);
 994                                 inp->inp_inc.inc_fibnum = so->so_fibnum;
 995                                 INP_WUNLOCK(inp);
 996                                 error = 0;
 997                                 break;
 998                         case SO_MAX_PACING_RATE:
 999 #ifdef RATELIMIT
1000                                 INP_WLOCK(inp);
1001                                 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1002                                 INP_WUNLOCK(inp);
1003                                 error = 0;
1004 #else
1005                                 error = EOPNOTSUPP;
1006 #endif
1007                                 break;
1008                         default:
1009                                 break;
1010                         }
1011                 }
1012                 return (error);
1013         }
1014
1015         switch (sopt->sopt_dir) {
1016         case SOPT_SET:
1017                 switch (sopt->sopt_name) {
1018                 case IP_OPTIONS:
1019 #ifdef notyet
1020                 case IP_RETOPTS:
1021 #endif
1022                 {
1023                         struct mbuf *m;
1024                         if (sopt->sopt_valsize > MLEN) {
1025                                 error = EMSGSIZE;
1026                                 break;
1027                         }
1028                         m = m_get(sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
1029                         if (m == NULL) {
1030                                 error = ENOBUFS;
1031                                 break;
1032                         }
1033                         m->m_len = sopt->sopt_valsize;
1034                         error = sooptcopyin(sopt, mtod(m, char *), m->m_len,
1035                                             m->m_len);
1036                         if (error) {
1037                                 m_free(m);
1038                                 break;
1039                         }
1040                         INP_WLOCK(inp);
1041                         error = ip_pcbopts(inp, sopt->sopt_name, m);
1042                         INP_WUNLOCK(inp);
1043                         return (error);
1044                 }
1045
1046                 case IP_BINDANY:
1047                         if (sopt->sopt_td != NULL) {
1048                                 error = priv_check(sopt->sopt_td,
1049                                     PRIV_NETINET_BINDANY);
1050                                 if (error)
1051                                         break;
1052                         }
1053                         /* FALLTHROUGH */
1054                 case IP_BINDMULTI:
1055 #ifdef  RSS
1056                 case IP_RSS_LISTEN_BUCKET:
1057 #endif
1058                 case IP_TOS:
1059                 case IP_TTL:
1060                 case IP_MINTTL:
1061                 case IP_RECVOPTS:
1062                 case IP_RECVRETOPTS:
1063                 case IP_ORIGDSTADDR:
1064                 case IP_RECVDSTADDR:
1065                 case IP_RECVTTL:
1066                 case IP_RECVIF:
1067                 case IP_ONESBCAST:
1068                 case IP_DONTFRAG:
1069                 case IP_RECVTOS:
1070                 case IP_RECVFLOWID:
1071 #ifdef  RSS
1072                 case IP_RECVRSSBUCKETID:
1073 #endif
1074                         error = sooptcopyin(sopt, &optval, sizeof optval,
1075                                             sizeof optval);
1076                         if (error)
1077                                 break;
1078
1079                         switch (sopt->sopt_name) {
1080                         case IP_TOS:
1081                                 inp->inp_ip_tos = optval;
1082                                 break;
1083
1084                         case IP_TTL:
1085                                 inp->inp_ip_ttl = optval;
1086                                 break;
1087
1088                         case IP_MINTTL:
1089                                 if (optval >= 0 && optval <= MAXTTL)
1090                                         inp->inp_ip_minttl = optval;
1091                                 else
1092                                         error = EINVAL;
1093                                 break;
1094
1095 #define OPTSET(bit) do {                                                \
1096         INP_WLOCK(inp);                                                 \
1097         if (optval)                                                     \
1098                 inp->inp_flags |= bit;                                  \
1099         else                                                            \
1100                 inp->inp_flags &= ~bit;                                 \
1101         INP_WUNLOCK(inp);                                               \
1102 } while (0)
1103
1104 #define OPTSET2(bit, val) do {                                          \
1105         INP_WLOCK(inp);                                                 \
1106         if (val)                                                        \
1107                 inp->inp_flags2 |= bit;                                 \
1108         else                                                            \
1109                 inp->inp_flags2 &= ~bit;                                \
1110         INP_WUNLOCK(inp);                                               \
1111 } while (0)
1112
1113                         case IP_RECVOPTS:
1114                                 OPTSET(INP_RECVOPTS);
1115                                 break;
1116
1117                         case IP_RECVRETOPTS:
1118                                 OPTSET(INP_RECVRETOPTS);
1119                                 break;
1120
1121                         case IP_RECVDSTADDR:
1122                                 OPTSET(INP_RECVDSTADDR);
1123                                 break;
1124
1125                         case IP_ORIGDSTADDR:
1126                                 OPTSET2(INP_ORIGDSTADDR, optval);
1127                                 break;
1128
1129                         case IP_RECVTTL:
1130                                 OPTSET(INP_RECVTTL);
1131                                 break;
1132
1133                         case IP_RECVIF:
1134                                 OPTSET(INP_RECVIF);
1135                                 break;
1136
1137                         case IP_ONESBCAST:
1138                                 OPTSET(INP_ONESBCAST);
1139                                 break;
1140                         case IP_DONTFRAG:
1141                                 OPTSET(INP_DONTFRAG);
1142                                 break;
1143                         case IP_BINDANY:
1144                                 OPTSET(INP_BINDANY);
1145                                 break;
1146                         case IP_RECVTOS:
1147                                 OPTSET(INP_RECVTOS);
1148                                 break;
1149                         case IP_BINDMULTI:
1150                                 OPTSET2(INP_BINDMULTI, optval);
1151                                 break;
1152                         case IP_RECVFLOWID:
1153                                 OPTSET2(INP_RECVFLOWID, optval);
1154                                 break;
1155 #ifdef  RSS
1156                         case IP_RSS_LISTEN_BUCKET:
1157                                 if ((optval >= 0) &&
1158                                     (optval < rss_getnumbuckets())) {
1159                                         inp->inp_rss_listen_bucket = optval;
1160                                         OPTSET2(INP_RSS_BUCKET_SET, 1);
1161                                 } else {
1162                                         error = EINVAL;
1163                                 }
1164                                 break;
1165                         case IP_RECVRSSBUCKETID:
1166                                 OPTSET2(INP_RECVRSSBUCKETID, optval);
1167                                 break;
1168 #endif
1169                         }
1170                         break;
1171 #undef OPTSET
1172 #undef OPTSET2
1173
1174                 /*
1175                  * Multicast socket options are processed by the in_mcast
1176                  * module.
1177                  */
1178                 case IP_MULTICAST_IF:
1179                 case IP_MULTICAST_VIF:
1180                 case IP_MULTICAST_TTL:
1181                 case IP_MULTICAST_LOOP:
1182                 case IP_ADD_MEMBERSHIP:
1183                 case IP_DROP_MEMBERSHIP:
1184                 case IP_ADD_SOURCE_MEMBERSHIP:
1185                 case IP_DROP_SOURCE_MEMBERSHIP:
1186                 case IP_BLOCK_SOURCE:
1187                 case IP_UNBLOCK_SOURCE:
1188                 case IP_MSFILTER:
1189                 case MCAST_JOIN_GROUP:
1190                 case MCAST_LEAVE_GROUP:
1191                 case MCAST_JOIN_SOURCE_GROUP:
1192                 case MCAST_LEAVE_SOURCE_GROUP:
1193                 case MCAST_BLOCK_SOURCE:
1194                 case MCAST_UNBLOCK_SOURCE:
1195                         error = inp_setmoptions(inp, sopt);
1196                         break;
1197
1198                 case IP_PORTRANGE:
1199                         error = sooptcopyin(sopt, &optval, sizeof optval,
1200                                             sizeof optval);
1201                         if (error)
1202                                 break;
1203
1204                         INP_WLOCK(inp);
1205                         switch (optval) {
1206                         case IP_PORTRANGE_DEFAULT:
1207                                 inp->inp_flags &= ~(INP_LOWPORT);
1208                                 inp->inp_flags &= ~(INP_HIGHPORT);
1209                                 break;
1210
1211                         case IP_PORTRANGE_HIGH:
1212                                 inp->inp_flags &= ~(INP_LOWPORT);
1213                                 inp->inp_flags |= INP_HIGHPORT;
1214                                 break;
1215
1216                         case IP_PORTRANGE_LOW:
1217                                 inp->inp_flags &= ~(INP_HIGHPORT);
1218                                 inp->inp_flags |= INP_LOWPORT;
1219                                 break;
1220
1221                         default:
1222                                 error = EINVAL;
1223                                 break;
1224                         }
1225                         INP_WUNLOCK(inp);
1226                         break;
1227
1228 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1229                 case IP_IPSEC_POLICY:
1230                         if (IPSEC_ENABLED(ipv4)) {
1231                                 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1232                                 break;
1233                         }
1234                         /* FALLTHROUGH */
1235 #endif /* IPSEC */
1236
1237                 default:
1238                         error = ENOPROTOOPT;
1239                         break;
1240                 }
1241                 break;
1242
1243         case SOPT_GET:
1244                 switch (sopt->sopt_name) {
1245                 case IP_OPTIONS:
1246                 case IP_RETOPTS:
1247                         if (inp->inp_options)
1248                                 error = sooptcopyout(sopt,
1249                                                      mtod(inp->inp_options,
1250                                                           char *),
1251                                                      inp->inp_options->m_len);
1252                         else
1253                                 sopt->sopt_valsize = 0;
1254                         break;
1255
1256                 case IP_TOS:
1257                 case IP_TTL:
1258                 case IP_MINTTL:
1259                 case IP_RECVOPTS:
1260                 case IP_RECVRETOPTS:
1261                 case IP_ORIGDSTADDR:
1262                 case IP_RECVDSTADDR:
1263                 case IP_RECVTTL:
1264                 case IP_RECVIF:
1265                 case IP_PORTRANGE:
1266                 case IP_ONESBCAST:
1267                 case IP_DONTFRAG:
1268                 case IP_BINDANY:
1269                 case IP_RECVTOS:
1270                 case IP_BINDMULTI:
1271                 case IP_FLOWID:
1272                 case IP_FLOWTYPE:
1273                 case IP_RECVFLOWID:
1274 #ifdef  RSS
1275                 case IP_RSSBUCKETID:
1276                 case IP_RECVRSSBUCKETID:
1277 #endif
1278                         switch (sopt->sopt_name) {
1279
1280                         case IP_TOS:
1281                                 optval = inp->inp_ip_tos;
1282                                 break;
1283
1284                         case IP_TTL:
1285                                 optval = inp->inp_ip_ttl;
1286                                 break;
1287
1288                         case IP_MINTTL:
1289                                 optval = inp->inp_ip_minttl;
1290                                 break;
1291
1292 #define OPTBIT(bit)     (inp->inp_flags & bit ? 1 : 0)
1293 #define OPTBIT2(bit)    (inp->inp_flags2 & bit ? 1 : 0)
1294
1295                         case IP_RECVOPTS:
1296                                 optval = OPTBIT(INP_RECVOPTS);
1297                                 break;
1298
1299                         case IP_RECVRETOPTS:
1300                                 optval = OPTBIT(INP_RECVRETOPTS);
1301                                 break;
1302
1303                         case IP_RECVDSTADDR:
1304                                 optval = OPTBIT(INP_RECVDSTADDR);
1305                                 break;
1306
1307                         case IP_ORIGDSTADDR:
1308                                 optval = OPTBIT2(INP_ORIGDSTADDR);
1309                                 break;
1310
1311                         case IP_RECVTTL:
1312                                 optval = OPTBIT(INP_RECVTTL);
1313                                 break;
1314
1315                         case IP_RECVIF:
1316                                 optval = OPTBIT(INP_RECVIF);
1317                                 break;
1318
1319                         case IP_PORTRANGE:
1320                                 if (inp->inp_flags & INP_HIGHPORT)
1321                                         optval = IP_PORTRANGE_HIGH;
1322                                 else if (inp->inp_flags & INP_LOWPORT)
1323                                         optval = IP_PORTRANGE_LOW;
1324                                 else
1325                                         optval = 0;
1326                                 break;
1327
1328                         case IP_ONESBCAST:
1329                                 optval = OPTBIT(INP_ONESBCAST);
1330                                 break;
1331                         case IP_DONTFRAG:
1332                                 optval = OPTBIT(INP_DONTFRAG);
1333                                 break;
1334                         case IP_BINDANY:
1335                                 optval = OPTBIT(INP_BINDANY);
1336                                 break;
1337                         case IP_RECVTOS:
1338                                 optval = OPTBIT(INP_RECVTOS);
1339                                 break;
1340                         case IP_FLOWID:
1341                                 optval = inp->inp_flowid;
1342                                 break;
1343                         case IP_FLOWTYPE:
1344                                 optval = inp->inp_flowtype;
1345                                 break;
1346                         case IP_RECVFLOWID:
1347                                 optval = OPTBIT2(INP_RECVFLOWID);
1348                                 break;
1349 #ifdef  RSS
1350                         case IP_RSSBUCKETID:
1351                                 retval = rss_hash2bucket(inp->inp_flowid,
1352                                     inp->inp_flowtype,
1353                                     &rss_bucket);
1354                                 if (retval == 0)
1355                                         optval = rss_bucket;
1356                                 else
1357                                         error = EINVAL;
1358                                 break;
1359                         case IP_RECVRSSBUCKETID:
1360                                 optval = OPTBIT2(INP_RECVRSSBUCKETID);
1361                                 break;
1362 #endif
1363                         case IP_BINDMULTI:
1364                                 optval = OPTBIT2(INP_BINDMULTI);
1365                                 break;
1366                         }
1367                         error = sooptcopyout(sopt, &optval, sizeof optval);
1368                         break;
1369
1370                 /*
1371                  * Multicast socket options are processed by the in_mcast
1372                  * module.
1373                  */
1374                 case IP_MULTICAST_IF:
1375                 case IP_MULTICAST_VIF:
1376                 case IP_MULTICAST_TTL:
1377                 case IP_MULTICAST_LOOP:
1378                 case IP_MSFILTER:
1379                         error = inp_getmoptions(inp, sopt);
1380                         break;
1381
1382 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1383                 case IP_IPSEC_POLICY:
1384                         if (IPSEC_ENABLED(ipv4)) {
1385                                 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1386                                 break;
1387                         }
1388                         /* FALLTHROUGH */
1389 #endif /* IPSEC */
1390
1391                 default:
1392                         error = ENOPROTOOPT;
1393                         break;
1394                 }
1395                 break;
1396         }
1397         return (error);
1398 }
1399
1400 /*
1401  * Routine called from ip_output() to loop back a copy of an IP multicast
1402  * packet to the input queue of a specified interface.  Note that this
1403  * calls the output routine of the loopback "driver", but with an interface
1404  * pointer that might NOT be a loopback interface -- evil, but easier than
1405  * replicating that code here.
1406  */
1407 static void
1408 ip_mloopback(struct ifnet *ifp, const struct mbuf *m, int hlen)
1409 {
1410         struct ip *ip;
1411         struct mbuf *copym;
1412
1413         /*
1414          * Make a deep copy of the packet because we're going to
1415          * modify the pack in order to generate checksums.
1416          */
1417         copym = m_dup(m, M_NOWAIT);
1418         if (copym != NULL && (!M_WRITABLE(copym) || copym->m_len < hlen))
1419                 copym = m_pullup(copym, hlen);
1420         if (copym != NULL) {
1421                 /* If needed, compute the checksum and mark it as valid. */
1422                 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
1423                         in_delayed_cksum(copym);
1424                         copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1425                         copym->m_pkthdr.csum_flags |=
1426                             CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1427                         copym->m_pkthdr.csum_data = 0xffff;
1428                 }
1429                 /*
1430                  * We don't bother to fragment if the IP length is greater
1431                  * than the interface's MTU.  Can this possibly matter?
1432                  */
1433                 ip = mtod(copym, struct ip *);
1434                 ip->ip_sum = 0;
1435                 ip->ip_sum = in_cksum(copym, hlen);
1436                 if_simloop(ifp, copym, AF_INET, 0);
1437         }
1438 }