sys/netinet/ip_output.c

   1 /*-
   2  * Copyright (c) 1982, 1986, 1988, 1990, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  *      @(#)ip_output.c 8.3 (Berkeley) 1/21/94
  30  */
  31
  32 #include <sys/cdefs.h>
  33 __FBSDID("$FreeBSD$");
  34
  35 #include "opt_inet.h"
  36 #include "opt_ratelimit.h"
  37 #include "opt_ipsec.h"
  38 #include "opt_mbuf_stress_test.h"
  39 #include "opt_mpath.h"
  40 #include "opt_route.h"
  41 #include "opt_sctp.h"
  42 #include "opt_rss.h"
  43
  44 #include <sys/param.h>
  45 #include <sys/systm.h>
  46 #include <sys/kernel.h>
  47 #include <sys/lock.h>
  48 #include <sys/malloc.h>
  49 #include <sys/mbuf.h>
  50 #include <sys/priv.h>
  51 #include <sys/proc.h>
  52 #include <sys/protosw.h>
  53 #include <sys/rmlock.h>
  54 #include <sys/sdt.h>
  55 #include <sys/socket.h>
  56 #include <sys/socketvar.h>
  57 #include <sys/sysctl.h>
  58 #include <sys/ucred.h>
  59
  60 #include <net/if.h>
  61 #include <net/if_var.h>
  62 #include <net/if_llatbl.h>
  63 #include <net/netisr.h>
  64 #include <net/pfil.h>
  65 #include <net/route.h>
  66 #include <net/flowtable.h>
  67 #ifdef RADIX_MPATH
  68 #include <net/radix_mpath.h>
  69 #endif
  70 #include <net/rss_config.h>
  71 #include <net/vnet.h>
  72
  73 #include <netinet/in.h>
  74 #include <netinet/in_kdtrace.h>
  75 #include <netinet/in_systm.h>
  76 #include <netinet/ip.h>
  77 #include <netinet/in_pcb.h>
  78 #include <netinet/in_rss.h>
  79 #include <netinet/in_var.h>
  80 #include <netinet/ip_var.h>
  81 #include <netinet/ip_options.h>
  82 #ifdef SCTP
  83 #include <netinet/sctp.h>
  84 #include <netinet/sctp_crc32.h>
  85 #endif
  86
  87 #include <netipsec/ipsec_support.h>
  88
  89 #include <machine/in_cksum.h>
  90
  91 #include <security/mac/mac_framework.h>
  92
  93 #ifdef MBUF_STRESS_TEST
  94 static int mbuf_frag_size = 0;
  95 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
  96         &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
  97 #endif
  98
  99 static void     ip_mloopback(struct ifnet *, const struct mbuf *, int);
 100
 101
 102 extern int in_mcast_loop;
 103 extern  struct protosw inetsw[];
 104
 105 static inline int
 106 ip_output_pfil(struct mbuf **mp, struct ifnet *ifp, struct inpcb *inp,
 107     struct sockaddr_in *dst, int *fibnum, int *error)
 108 {
 109         struct m_tag *fwd_tag = NULL;
 110         struct mbuf *m;
 111         struct in_addr odst;
 112         struct ip *ip;
 113
 114         m = *mp;
 115         ip = mtod(m, struct ip *);
 116
 117         /* Run through list of hooks for output packets. */
 118         odst.s_addr = ip->ip_dst.s_addr;
 119         *error = pfil_run_hooks(&V_inet_pfil_hook, mp, ifp, PFIL_OUT, inp);
 120         m = *mp;
 121         if ((*error) != 0 || m == NULL)
 122                 return 1; /* Finished */
 123
 124         ip = mtod(m, struct ip *);
 125
 126         /* See if destination IP address was changed by packet filter. */
 127         if (odst.s_addr != ip->ip_dst.s_addr) {
 128                 m->m_flags |= M_SKIP_FIREWALL;
 129                 /* If destination is now ourself drop to ip_input(). */
 130                 if (in_localip(ip->ip_dst)) {
 131                         m->m_flags |= M_FASTFWD_OURS;
 132                         if (m->m_pkthdr.rcvif == NULL)
 133                                 m->m_pkthdr.rcvif = V_loif;
 134                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 135                                 m->m_pkthdr.csum_flags |=
 136                                         CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
 137                                 m->m_pkthdr.csum_data = 0xffff;
 138                         }
 139                         m->m_pkthdr.csum_flags |=
 140                                 CSUM_IP_CHECKED | CSUM_IP_VALID;
 141 #ifdef SCTP
 142                         if (m->m_pkthdr.csum_flags & CSUM_SCTP)
 143                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 144 #endif
 145                         *error = netisr_queue(NETISR_IP, m);
 146                         return 1; /* Finished */
 147                 }
 148
 149                 bzero(dst, sizeof(*dst));
 150                 dst->sin_family = AF_INET;
 151                 dst->sin_len = sizeof(*dst);
 152                 dst->sin_addr = ip->ip_dst;
 153
 154                 return -1; /* Reloop */
 155         }
 156         /* See if fib was changed by packet filter. */
 157         if ((*fibnum) != M_GETFIB(m)) {
 158                 m->m_flags |= M_SKIP_FIREWALL;
 159                 *fibnum = M_GETFIB(m);
 160                 return -1; /* Reloop for FIB change */
 161         }
 162
 163         /* See if local, if yes, send it to netisr with IP_FASTFWD_OURS. */
 164         if (m->m_flags & M_FASTFWD_OURS) {
 165                 if (m->m_pkthdr.rcvif == NULL)
 166                         m->m_pkthdr.rcvif = V_loif;
 167                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 168                         m->m_pkthdr.csum_flags |=
 169                                 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
 170                         m->m_pkthdr.csum_data = 0xffff;
 171                 }
 172 #ifdef SCTP
 173                 if (m->m_pkthdr.csum_flags & CSUM_SCTP)
 174                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 175 #endif
 176                 m->m_pkthdr.csum_flags |=
 177                         CSUM_IP_CHECKED | CSUM_IP_VALID;
 178
 179                 *error = netisr_queue(NETISR_IP, m);
 180                 return 1; /* Finished */
 181         }
 182         /* Or forward to some other address? */
 183         if ((m->m_flags & M_IP_NEXTHOP) &&
 184             ((fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL)) {
 185                 bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in));
 186                 m->m_flags |= M_SKIP_FIREWALL;
 187                 m->m_flags &= ~M_IP_NEXTHOP;
 188                 m_tag_delete(m, fwd_tag);
 189
 190                 return -1; /* Reloop for CHANGE of dst */
 191         }
 192
 193         return 0;
 194 }
 195
 196 /*
 197  * IP output.  The packet in mbuf chain m contains a skeletal IP
 198  * header (with len, off, ttl, proto, tos, src, dst).
 199  * The mbuf chain containing the packet will be freed.
 200  * The mbuf opt, if present, will not be freed.
 201  * If route ro is present and has ro_rt initialized, route lookup would be
 202  * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
 203  * then result of route lookup is stored in ro->ro_rt.
 204  *
 205  * In the IP forwarding case, the packet will arrive with options already
 206  * inserted, so must have a NULL opt pointer.
 207  */
 208 int
 209 ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
 210     struct ip_moptions *imo, struct inpcb *inp)
 211 {
 212         struct rm_priotracker in_ifa_tracker;
 213         struct ip *ip;
 214         struct ifnet *ifp = NULL;       /* keep compiler happy */
 215         struct mbuf *m0;
 216         int hlen = sizeof (struct ip);
 217         int mtu;
 218         int error = 0;
 219         struct sockaddr_in *dst;
 220         const struct sockaddr_in *gw;
 221         struct in_ifaddr *ia;
 222         int isbroadcast;
 223         uint16_t ip_len, ip_off;
 224         struct route iproute;
 225         struct rtentry *rte;    /* cache for ro->ro_rt */
 226         uint32_t fibnum;
 227         int have_ia_ref;
 228 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 229         int no_route_but_check_spd = 0;
 230 #endif
 231         M_ASSERTPKTHDR(m);
 232
 233         if (inp != NULL) {
 234                 INP_LOCK_ASSERT(inp);
 235                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 236                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 237                         m->m_pkthdr.flowid = inp->inp_flowid;
 238                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 239                 }
 240         }
 241
 242         if (ro == NULL) {
 243                 ro = &iproute;
 244                 bzero(ro, sizeof (*ro));
 245         }
 246
 247 #ifdef FLOWTABLE
 248         if (ro->ro_rt == NULL)
 249                 (void )flowtable_lookup(AF_INET, m, ro);
 250 #endif
 251
 252         if (opt) {
 253                 int len = 0;
 254                 m = ip_insertoptions(m, opt, &len);
 255                 if (len != 0)
 256                         hlen = len; /* ip->ip_hl is updated above */
 257         }
 258         ip = mtod(m, struct ip *);
 259         ip_len = ntohs(ip->ip_len);
 260         ip_off = ntohs(ip->ip_off);
 261
 262         if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) {
 263                 ip->ip_v = IPVERSION;
 264                 ip->ip_hl = hlen >> 2;
 265                 ip_fillid(ip);
 266                 IPSTAT_INC(ips_localout);
 267         } else {
 268                 /* Header already set, fetch hlen from there */
 269                 hlen = ip->ip_hl << 2;
 270         }
 271
 272         /*
 273          * dst/gw handling:
 274          *
 275          * dst can be rewritten but always points to &ro->ro_dst.
 276          * gw is readonly but can point either to dst OR rt_gateway,
 277          * therefore we need restore gw if we're redoing lookup.
 278          */
 279         gw = dst = (struct sockaddr_in *)&ro->ro_dst;
 280         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 281         rte = ro->ro_rt;
 282         if (rte == NULL) {
 283                 bzero(dst, sizeof(*dst));
 284                 dst->sin_family = AF_INET;
 285                 dst->sin_len = sizeof(*dst);
 286                 dst->sin_addr = ip->ip_dst;
 287         }
 288 again:
 289         /*
 290          * Validate route against routing table additions;
 291          * a better/more specific route might have been added.
 292          */
 293         if (inp)
 294                 RT_VALIDATE(ro, &inp->inp_rt_cookie, fibnum);
 295         /*
 296          * If there is a cached route,
 297          * check that it is to the same destination
 298          * and is still up.  If not, free it and try again.
 299          * The address family should also be checked in case of sharing the
 300          * cache with IPv6.
 301          * Also check whether routing cache needs invalidation.
 302          */
 303         rte = ro->ro_rt;
 304         if (rte && ((rte->rt_flags & RTF_UP) == 0 ||
 305                     rte->rt_ifp == NULL ||
 306                     !RT_LINK_IS_UP(rte->rt_ifp) ||
 307                           dst->sin_family != AF_INET ||
 308                           dst->sin_addr.s_addr != ip->ip_dst.s_addr)) {
 309                 RTFREE(rte);
 310                 rte = ro->ro_rt = (struct rtentry *)NULL;
 311                 if (ro->ro_lle)
 312                         LLE_FREE(ro->ro_lle);   /* zeros ro_lle */
 313                 ro->ro_lle = (struct llentry *)NULL;
 314         }
 315         ia = NULL;
 316         have_ia_ref = 0;
 317         /*
 318          * If routing to interface only, short circuit routing lookup.
 319          * The use of an all-ones broadcast address implies this; an
 320          * interface is specified by the broadcast address of an interface,
 321          * or the destination address of a ptp interface.
 322          */
 323         if (flags & IP_SENDONES) {
 324                 if ((ia = ifatoia(ifa_ifwithbroadaddr(sintosa(dst),
 325                                                       M_GETFIB(m)))) == NULL &&
 326                     (ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
 327                                                     M_GETFIB(m)))) == NULL) {
 328                         IPSTAT_INC(ips_noroute);
 329                         error = ENETUNREACH;
 330                         goto bad;
 331                 }
 332                 have_ia_ref = 1;
 333                 ip->ip_dst.s_addr = INADDR_BROADCAST;
 334                 dst->sin_addr = ip->ip_dst;
 335                 ifp = ia->ia_ifp;
 336                 ip->ip_ttl = 1;
 337                 isbroadcast = 1;
 338         } else if (flags & IP_ROUTETOIF) {
 339                 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
 340                                                     M_GETFIB(m)))) == NULL &&
 341                     (ia = ifatoia(ifa_ifwithnet(sintosa(dst), 0,
 342                                                 M_GETFIB(m)))) == NULL) {
 343                         IPSTAT_INC(ips_noroute);
 344                         error = ENETUNREACH;
 345                         goto bad;
 346                 }
 347                 have_ia_ref = 1;
 348                 ifp = ia->ia_ifp;
 349                 ip->ip_ttl = 1;
 350                 isbroadcast = ifp->if_flags & IFF_BROADCAST ?
 351                     in_ifaddr_broadcast(dst->sin_addr, ia) : 0;
 352         } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
 353             imo != NULL && imo->imo_multicast_ifp != NULL) {
 354                 /*
 355                  * Bypass the normal routing lookup for multicast
 356                  * packets if the interface is specified.
 357                  */
 358                 ifp = imo->imo_multicast_ifp;
 359                 IFP_TO_IA(ifp, ia, &in_ifa_tracker);
 360                 if (ia)
 361                         have_ia_ref = 1;
 362                 isbroadcast = 0;        /* fool gcc */
 363         } else {
 364                 /*
 365                  * We want to do any cloning requested by the link layer,
 366                  * as this is probably required in all cases for correct
 367                  * operation (as it is for ARP).
 368                  */
 369                 if (rte == NULL) {
 370 #ifdef RADIX_MPATH
 371                         rtalloc_mpath_fib(ro,
 372                             ntohl(ip->ip_src.s_addr ^ ip->ip_dst.s_addr),
 373                             fibnum);
 374 #else
 375                         in_rtalloc_ign(ro, 0, fibnum);
 376 #endif
 377                         rte = ro->ro_rt;
 378                 }
 379                 if (rte == NULL ||
 380                     (rte->rt_flags & RTF_UP) == 0 ||
 381                     rte->rt_ifp == NULL ||
 382                     !RT_LINK_IS_UP(rte->rt_ifp)) {
 383 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 384                         /*
 385                          * There is no route for this packet, but it is
 386                          * possible that a matching SPD entry exists.
 387                          */
 388                         no_route_but_check_spd = 1;
 389                         mtu = 0; /* Silence GCC warning. */
 390                         goto sendit;
 391 #endif
 392                         IPSTAT_INC(ips_noroute);
 393                         error = EHOSTUNREACH;
 394                         goto bad;
 395                 }
 396                 ia = ifatoia(rte->rt_ifa);
 397                 ifp = rte->rt_ifp;
 398                 counter_u64_add(rte->rt_pksent, 1);
 399                 rt_update_ro_flags(ro);
 400                 if (rte->rt_flags & RTF_GATEWAY)
 401                         gw = (struct sockaddr_in *)rte->rt_gateway;
 402                 if (rte->rt_flags & RTF_HOST)
 403                         isbroadcast = (rte->rt_flags & RTF_BROADCAST);
 404                 else if (ifp->if_flags & IFF_BROADCAST)
 405                         isbroadcast = in_ifaddr_broadcast(gw->sin_addr, ia);
 406                 else
 407                         isbroadcast = 0;
 408         }
 409
 410         /*
 411          * Calculate MTU.  If we have a route that is up, use that,
 412          * otherwise use the interface's MTU.
 413          */
 414         if (rte != NULL && (rte->rt_flags & (RTF_UP|RTF_HOST)))
 415                 mtu = rte->rt_mtu;
 416         else
 417                 mtu = ifp->if_mtu;
 418         /* Catch a possible divide by zero later. */
 419         KASSERT(mtu > 0, ("%s: mtu %d <= 0, rte=%p (rt_flags=0x%08x) ifp=%p",
 420             __func__, mtu, rte, (rte != NULL) ? rte->rt_flags : 0, ifp));
 421
 422         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
 423                 m->m_flags |= M_MCAST;
 424                 /*
 425                  * IP destination address is multicast.  Make sure "gw"
 426                  * still points to the address in "ro".  (It may have been
 427                  * changed to point to a gateway address, above.)
 428                  */
 429                 gw = dst;
 430                 /*
 431                  * See if the caller provided any multicast options
 432                  */
 433                 if (imo != NULL) {
 434                         ip->ip_ttl = imo->imo_multicast_ttl;
 435                         if (imo->imo_multicast_vif != -1)
 436                                 ip->ip_src.s_addr =
 437                                     ip_mcast_src ?
 438                                     ip_mcast_src(imo->imo_multicast_vif) :
 439                                     INADDR_ANY;
 440                 } else
 441                         ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
 442                 /*
 443                  * Confirm that the outgoing interface supports multicast.
 444                  */
 445                 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
 446                         if ((ifp->if_flags & IFF_MULTICAST) == 0) {
 447                                 IPSTAT_INC(ips_noroute);
 448                                 error = ENETUNREACH;
 449                                 goto bad;
 450                         }
 451                 }
 452                 /*
 453                  * If source address not specified yet, use address
 454                  * of outgoing interface.
 455                  */
 456                 if (ip->ip_src.s_addr == INADDR_ANY) {
 457                         /* Interface may have no addresses. */
 458                         if (ia != NULL)
 459                                 ip->ip_src = IA_SIN(ia)->sin_addr;
 460                 }
 461
 462                 if ((imo == NULL && in_mcast_loop) ||
 463                     (imo && imo->imo_multicast_loop)) {
 464                         /*
 465                          * Loop back multicast datagram if not expressly
 466                          * forbidden to do so, even if we are not a member
 467                          * of the group; ip_input() will filter it later,
 468                          * thus deferring a hash lookup and mutex acquisition
 469                          * at the expense of a cheap copy using m_copym().
 470                          */
 471                         ip_mloopback(ifp, m, hlen);
 472                 } else {
 473                         /*
 474                          * If we are acting as a multicast router, perform
 475                          * multicast forwarding as if the packet had just
 476                          * arrived on the interface to which we are about
 477                          * to send.  The multicast forwarding function
 478                          * recursively calls this function, using the
 479                          * IP_FORWARDING flag to prevent infinite recursion.
 480                          *
 481                          * Multicasts that are looped back by ip_mloopback(),
 482                          * above, will be forwarded by the ip_input() routine,
 483                          * if necessary.
 484                          */
 485                         if (V_ip_mrouter && (flags & IP_FORWARDING) == 0) {
 486                                 /*
 487                                  * If rsvp daemon is not running, do not
 488                                  * set ip_moptions. This ensures that the packet
 489                                  * is multicast and not just sent down one link
 490                                  * as prescribed by rsvpd.
 491                                  */
 492                                 if (!V_rsvp_on)
 493                                         imo = NULL;
 494                                 if (ip_mforward &&
 495                                     ip_mforward(ip, ifp, m, imo) != 0) {
 496                                         m_freem(m);
 497                                         goto done;
 498                                 }
 499                         }
 500                 }
 501
 502                 /*
 503                  * Multicasts with a time-to-live of zero may be looped-
 504                  * back, above, but must not be transmitted on a network.
 505                  * Also, multicasts addressed to the loopback interface
 506                  * are not sent -- the above call to ip_mloopback() will
 507                  * loop back a copy. ip_input() will drop the copy if
 508                  * this host does not belong to the destination group on
 509                  * the loopback interface.
 510                  */
 511                 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
 512                         m_freem(m);
 513                         goto done;
 514                 }
 515
 516                 goto sendit;
 517         }
 518
 519         /*
 520          * If the source address is not specified yet, use the address
 521          * of the outoing interface.
 522          */
 523         if (ip->ip_src.s_addr == INADDR_ANY) {
 524                 /* Interface may have no addresses. */
 525                 if (ia != NULL) {
 526                         ip->ip_src = IA_SIN(ia)->sin_addr;
 527                 }
 528         }
 529
 530         /*
 531          * Look for broadcast address and
 532          * verify user is allowed to send
 533          * such a packet.
 534          */
 535         if (isbroadcast) {
 536                 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
 537                         error = EADDRNOTAVAIL;
 538                         goto bad;
 539                 }
 540                 if ((flags & IP_ALLOWBROADCAST) == 0) {
 541                         error = EACCES;
 542                         goto bad;
 543                 }
 544                 /* don't allow broadcast messages to be fragmented */
 545                 if (ip_len > mtu) {
 546                         error = EMSGSIZE;
 547                         goto bad;
 548                 }
 549                 m->m_flags |= M_BCAST;
 550         } else {
 551                 m->m_flags &= ~M_BCAST;
 552         }
 553
 554 sendit:
 555 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 556         if (IPSEC_ENABLED(ipv4)) {
 557                 if ((error = IPSEC_OUTPUT(ipv4, m, inp)) != 0) {
 558                         if (error == EINPROGRESS)
 559                                 error = 0;
 560                         goto done;
 561                 }
 562         }
 563         /*
 564          * Check if there was a route for this packet; return error if not.
 565          */
 566         if (no_route_but_check_spd) {
 567                 IPSTAT_INC(ips_noroute);
 568                 error = EHOSTUNREACH;
 569                 goto bad;
 570         }
 571         /* Update variables that are affected by ipsec4_output(). */
 572         ip = mtod(m, struct ip *);
 573         hlen = ip->ip_hl << 2;
 574 #endif /* IPSEC */
 575
 576         /* Jump over all PFIL processing if hooks are not active. */
 577         if (PFIL_HOOKED(&V_inet_pfil_hook)) {
 578                 switch (ip_output_pfil(&m, ifp, inp, dst, &fibnum, &error)) {
 579                 case 1: /* Finished */
 580                         goto done;
 581
 582                 case 0: /* Continue normally */
 583                         ip = mtod(m, struct ip *);
 584                         break;
 585
 586                 case -1: /* Need to try again */
 587                         /* Reset everything for a new round */
 588                         RO_RTFREE(ro);
 589                         if (have_ia_ref)
 590                                 ifa_free(&ia->ia_ifa);
 591                         ro->ro_prepend = NULL;
 592                         rte = NULL;
 593                         gw = dst;
 594                         ip = mtod(m, struct ip *);
 595                         goto again;
 596
 597                 }
 598         }
 599
 600         /* 127/8 must not appear on wire - RFC1122. */
 601         if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
 602             (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
 603                 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
 604                         IPSTAT_INC(ips_badaddr);
 605                         error = EADDRNOTAVAIL;
 606                         goto bad;
 607                 }
 608         }
 609
 610         m->m_pkthdr.csum_flags |= CSUM_IP;
 611         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
 612                 in_delayed_cksum(m);
 613                 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
 614         }
 615 #ifdef SCTP
 616         if (m->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
 617                 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
 618                 m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
 619         }
 620 #endif
 621
 622         /*
 623          * If small enough for interface, or the interface will take
 624          * care of the fragmentation for us, we can just send directly.
 625          */
 626         if (ip_len <= mtu ||
 627             (m->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0) {
 628                 ip->ip_sum = 0;
 629                 if (m->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
 630                         ip->ip_sum = in_cksum(m, hlen);
 631                         m->m_pkthdr.csum_flags &= ~CSUM_IP;
 632                 }
 633
 634                 /*
 635                  * Record statistics for this interface address.
 636                  * With CSUM_TSO the byte/packet count will be slightly
 637                  * incorrect because we count the IP+TCP headers only
 638                  * once instead of for every generated packet.
 639                  */
 640                 if (!(flags & IP_FORWARDING) && ia) {
 641                         if (m->m_pkthdr.csum_flags & CSUM_TSO)
 642                                 counter_u64_add(ia->ia_ifa.ifa_opackets,
 643                                     m->m_pkthdr.len / m->m_pkthdr.tso_segsz);
 644                         else
 645                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
 646
 647                         counter_u64_add(ia->ia_ifa.ifa_obytes, m->m_pkthdr.len);
 648                 }
 649 #ifdef MBUF_STRESS_TEST
 650                 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size)
 651                         m = m_fragment(m, M_NOWAIT, mbuf_frag_size);
 652 #endif
 653                 /*
 654                  * Reset layer specific mbuf flags
 655                  * to avoid confusing lower layers.
 656                  */
 657                 m_clrprotoflags(m);
 658                 IP_PROBE(send, NULL, NULL, ip, ifp, ip, NULL);
 659 #ifdef RATELIMIT
 660                 if (inp != NULL) {
 661                         if (inp->inp_flags2 & INP_RATE_LIMIT_CHANGED)
 662                                 in_pcboutput_txrtlmt(inp, ifp, m);
 663                         /* stamp send tag on mbuf */
 664                         m->m_pkthdr.snd_tag = inp->inp_snd_tag;
 665                 } else {
 666                         m->m_pkthdr.snd_tag = NULL;
 667                 }
 668 #endif
 669                 error = (*ifp->if_output)(ifp, m,
 670                     (const struct sockaddr *)gw, ro);
 671 #ifdef RATELIMIT
 672                 /* check for route change */
 673                 if (error == EAGAIN)
 674                         in_pcboutput_eagain(inp);
 675 #endif
 676                 goto done;
 677         }
 678
 679         /* Balk when DF bit is set or the interface didn't support TSO. */
 680         if ((ip_off & IP_DF) || (m->m_pkthdr.csum_flags & CSUM_TSO)) {
 681                 error = EMSGSIZE;
 682                 IPSTAT_INC(ips_cantfrag);
 683                 goto bad;
 684         }
 685
 686         /*
 687          * Too large for interface; fragment if possible. If successful,
 688          * on return, m will point to a list of packets to be sent.
 689          */
 690         error = ip_fragment(ip, &m, mtu, ifp->if_hwassist);
 691         if (error)
 692                 goto bad;
 693         for (; m; m = m0) {
 694                 m0 = m->m_nextpkt;
 695                 m->m_nextpkt = 0;
 696                 if (error == 0) {
 697                         /* Record statistics for this interface address. */
 698                         if (ia != NULL) {
 699                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
 700                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
 701                                     m->m_pkthdr.len);
 702                         }
 703                         /*
 704                          * Reset layer specific mbuf flags
 705                          * to avoid confusing upper layers.
 706                          */
 707                         m_clrprotoflags(m);
 708
 709                         IP_PROBE(send, NULL, NULL, mtod(m, struct ip *), ifp,
 710                             mtod(m, struct ip *), NULL);
 711 #ifdef RATELIMIT
 712                         if (inp != NULL) {
 713                                 if (inp->inp_flags2 & INP_RATE_LIMIT_CHANGED)
 714                                         in_pcboutput_txrtlmt(inp, ifp, m);
 715                                 /* stamp send tag on mbuf */
 716                                 m->m_pkthdr.snd_tag = inp->inp_snd_tag;
 717                         } else {
 718                                 m->m_pkthdr.snd_tag = NULL;
 719                         }
 720 #endif
 721                         error = (*ifp->if_output)(ifp, m,
 722                             (const struct sockaddr *)gw, ro);
 723 #ifdef RATELIMIT
 724                         /* check for route change */
 725                         if (error == EAGAIN)
 726                                 in_pcboutput_eagain(inp);
 727 #endif
 728                 } else
 729                         m_freem(m);
 730         }
 731
 732         if (error == 0)
 733                 IPSTAT_INC(ips_fragmented);
 734
 735 done:
 736         if (ro == &iproute)
 737                 RO_RTFREE(ro);
 738         else if (rte == NULL)
 739                 /*
 740                  * If the caller supplied a route but somehow the reference
 741                  * to it has been released need to prevent the caller
 742                  * calling RTFREE on it again.
 743                  */
 744                 ro->ro_rt = NULL;
 745         if (have_ia_ref)
 746                 ifa_free(&ia->ia_ifa);
 747         return (error);
 748 bad:
 749         m_freem(m);
 750         goto done;
 751 }
 752
 753 /*
 754  * Create a chain of fragments which fit the given mtu. m_frag points to the
 755  * mbuf to be fragmented; on return it points to the chain with the fragments.
 756  * Return 0 if no error. If error, m_frag may contain a partially built
 757  * chain of fragments that should be freed by the caller.
 758  *
 759  * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
 760  */
 761 int
 762 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
 763     u_long if_hwassist_flags)
 764 {
 765         int error = 0;
 766         int hlen = ip->ip_hl << 2;
 767         int len = (mtu - hlen) & ~7;    /* size of payload in each fragment */
 768         int off;
 769         struct mbuf *m0 = *m_frag;      /* the original packet          */
 770         int firstlen;
 771         struct mbuf **mnext;
 772         int nfrags;
 773         uint16_t ip_len, ip_off;
 774
 775         ip_len = ntohs(ip->ip_len);
 776         ip_off = ntohs(ip->ip_off);
 777
 778         if (ip_off & IP_DF) {   /* Fragmentation not allowed */
 779                 IPSTAT_INC(ips_cantfrag);
 780                 return EMSGSIZE;
 781         }
 782
 783         /*
 784          * Must be able to put at least 8 bytes per fragment.
 785          */
 786         if (len < 8)
 787                 return EMSGSIZE;
 788
 789         /*
 790          * If the interface will not calculate checksums on
 791          * fragmented packets, then do it here.
 792          */
 793         if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 794                 in_delayed_cksum(m0);
 795                 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
 796         }
 797 #ifdef SCTP
 798         if (m0->m_pkthdr.csum_flags & CSUM_SCTP) {
 799                 sctp_delayed_cksum(m0, hlen);
 800                 m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
 801         }
 802 #endif
 803         if (len > PAGE_SIZE) {
 804                 /*
 805                  * Fragment large datagrams such that each segment
 806                  * contains a multiple of PAGE_SIZE amount of data,
 807                  * plus headers. This enables a receiver to perform
 808                  * page-flipping zero-copy optimizations.
 809                  *
 810                  * XXX When does this help given that sender and receiver
 811                  * could have different page sizes, and also mtu could
 812                  * be less than the receiver's page size ?
 813                  */
 814                 int newlen;
 815
 816                 off = MIN(mtu, m0->m_pkthdr.len);
 817
 818                 /*
 819                  * firstlen (off - hlen) must be aligned on an
 820                  * 8-byte boundary
 821                  */
 822                 if (off < hlen)
 823                         goto smart_frag_failure;
 824                 off = ((off - hlen) & ~7) + hlen;
 825                 newlen = (~PAGE_MASK) & mtu;
 826                 if ((newlen + sizeof (struct ip)) > mtu) {
 827                         /* we failed, go back the default */
 828 smart_frag_failure:
 829                         newlen = len;
 830                         off = hlen + len;
 831                 }
 832                 len = newlen;
 833
 834         } else {
 835                 off = hlen + len;
 836         }
 837
 838         firstlen = off - hlen;
 839         mnext = &m0->m_nextpkt;         /* pointer to next packet */
 840
 841         /*
 842          * Loop through length of segment after first fragment,
 843          * make new header and copy data of each part and link onto chain.
 844          * Here, m0 is the original packet, m is the fragment being created.
 845          * The fragments are linked off the m_nextpkt of the original
 846          * packet, which after processing serves as the first fragment.
 847          */
 848         for (nfrags = 1; off < ip_len; off += len, nfrags++) {
 849                 struct ip *mhip;        /* ip header on the fragment */
 850                 struct mbuf *m;
 851                 int mhlen = sizeof (struct ip);
 852
 853                 m = m_gethdr(M_NOWAIT, MT_DATA);
 854                 if (m == NULL) {
 855                         error = ENOBUFS;
 856                         IPSTAT_INC(ips_odropped);
 857                         goto done;
 858                 }
 859                 /*
 860                  * Make sure the complete packet header gets copied
 861                  * from the originating mbuf to the newly created
 862                  * mbuf. This also ensures that existing firewall
 863                  * classification(s), VLAN tags and so on get copied
 864                  * to the resulting fragmented packet(s):
 865                  */
 866                 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
 867                         m_free(m);
 868                         error = ENOBUFS;
 869                         IPSTAT_INC(ips_odropped);
 870                         goto done;
 871                 }
 872                 /*
 873                  * In the first mbuf, leave room for the link header, then
 874                  * copy the original IP header including options. The payload
 875                  * goes into an additional mbuf chain returned by m_copym().
 876                  */
 877                 m->m_data += max_linkhdr;
 878                 mhip = mtod(m, struct ip *);
 879                 *mhip = *ip;
 880                 if (hlen > sizeof (struct ip)) {
 881                         mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
 882                         mhip->ip_v = IPVERSION;
 883                         mhip->ip_hl = mhlen >> 2;
 884                 }
 885                 m->m_len = mhlen;
 886                 /* XXX do we need to add ip_off below ? */
 887                 mhip->ip_off = ((off - hlen) >> 3) + ip_off;
 888                 if (off + len >= ip_len)
 889                         len = ip_len - off;
 890                 else
 891                         mhip->ip_off |= IP_MF;
 892                 mhip->ip_len = htons((u_short)(len + mhlen));
 893                 m->m_next = m_copym(m0, off, len, M_NOWAIT);
 894                 if (m->m_next == NULL) {        /* copy failed */
 895                         m_free(m);
 896                         error = ENOBUFS;        /* ??? */
 897                         IPSTAT_INC(ips_odropped);
 898                         goto done;
 899                 }
 900                 m->m_pkthdr.len = mhlen + len;
 901 #ifdef MAC
 902                 mac_netinet_fragment(m0, m);
 903 #endif
 904                 mhip->ip_off = htons(mhip->ip_off);
 905                 mhip->ip_sum = 0;
 906                 if (m->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
 907                         mhip->ip_sum = in_cksum(m, mhlen);
 908                         m->m_pkthdr.csum_flags &= ~CSUM_IP;
 909                 }
 910                 *mnext = m;
 911                 mnext = &m->m_nextpkt;
 912         }
 913         IPSTAT_ADD(ips_ofragments, nfrags);
 914
 915         /*
 916          * Update first fragment by trimming what's been copied out
 917          * and updating header.
 918          */
 919         m_adj(m0, hlen + firstlen - ip_len);
 920         m0->m_pkthdr.len = hlen + firstlen;
 921         ip->ip_len = htons((u_short)m0->m_pkthdr.len);
 922         ip->ip_off = htons(ip_off | IP_MF);
 923         ip->ip_sum = 0;
 924         if (m0->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
 925                 ip->ip_sum = in_cksum(m0, hlen);
 926                 m0->m_pkthdr.csum_flags &= ~CSUM_IP;
 927         }
 928
 929 done:
 930         *m_frag = m0;
 931         return error;
 932 }
 933
 934 void
 935 in_delayed_cksum(struct mbuf *m)
 936 {
 937         struct ip *ip;
 938         uint16_t csum, offset, ip_len;
 939
 940         ip = mtod(m, struct ip *);
 941         offset = ip->ip_hl << 2 ;
 942         ip_len = ntohs(ip->ip_len);
 943         csum = in_cksum_skip(m, ip_len, offset);
 944         if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0)
 945                 csum = 0xffff;
 946         offset += m->m_pkthdr.csum_data;        /* checksum offset */
 947
 948         /* find the mbuf in the chain where the checksum starts*/
 949         while ((m != NULL) && (offset >= m->m_len)) {
 950                 offset -= m->m_len;
 951                 m = m->m_next;
 952         }
 953         KASSERT(m != NULL, ("in_delayed_cksum: checksum outside mbuf chain."));
 954         KASSERT(offset + sizeof(u_short) <= m->m_len, ("in_delayed_cksum: checksum split between mbufs."));
 955         *(u_short *)(m->m_data + offset) = csum;
 956 }
 957
 958 /*
 959  * IP socket option processing.
 960  */
 961 int
 962 ip_ctloutput(struct socket *so, struct sockopt *sopt)
 963 {
 964         struct  inpcb *inp = sotoinpcb(so);
 965         int     error, optval;
 966 #ifdef  RSS
 967         uint32_t rss_bucket;
 968         int retval;
 969 #endif
 970
 971         error = optval = 0;
 972         if (sopt->sopt_level != IPPROTO_IP) {
 973                 error = EINVAL;
 974
 975                 if (sopt->sopt_level == SOL_SOCKET &&
 976                     sopt->sopt_dir == SOPT_SET) {
 977                         switch (sopt->sopt_name) {
 978                         case SO_REUSEADDR:
 979                                 INP_WLOCK(inp);
 980                                 if ((so->so_options & SO_REUSEADDR) != 0)
 981                                         inp->inp_flags2 |= INP_REUSEADDR;
 982                                 else
 983                                         inp->inp_flags2 &= ~INP_REUSEADDR;
 984                                 INP_WUNLOCK(inp);
 985                                 error = 0;
 986                                 break;
 987                         case SO_REUSEPORT:
 988                                 INP_WLOCK(inp);
 989                                 if ((so->so_options & SO_REUSEPORT) != 0)
 990                                         inp->inp_flags2 |= INP_REUSEPORT;
 991                                 else
 992                                         inp->inp_flags2 &= ~INP_REUSEPORT;
 993                                 INP_WUNLOCK(inp);
 994                                 error = 0;
 995                                 break;
 996                         case SO_SETFIB:
 997                                 INP_WLOCK(inp);
 998                                 inp->inp_inc.inc_fibnum = so->so_fibnum;
 999                                 INP_WUNLOCK(inp);
1000                                 error = 0;
1001                                 break;
1002                         case SO_MAX_PACING_RATE:
1003 #ifdef RATELIMIT
1004                                 INP_WLOCK(inp);
1005                                 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1006                                 INP_WUNLOCK(inp);
1007                                 error = 0;
1008 #else
1009                                 error = EOPNOTSUPP;
1010 #endif
1011                                 break;
1012                         default:
1013                                 break;
1014                         }
1015                 }
1016                 return (error);
1017         }
1018
1019         switch (sopt->sopt_dir) {
1020         case SOPT_SET:
1021                 switch (sopt->sopt_name) {
1022                 case IP_OPTIONS:
1023 #ifdef notyet
1024                 case IP_RETOPTS:
1025 #endif
1026                 {
1027                         struct mbuf *m;
1028                         if (sopt->sopt_valsize > MLEN) {
1029                                 error = EMSGSIZE;
1030                                 break;
1031                         }
1032                         m = m_get(sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
1033                         if (m == NULL) {
1034                                 error = ENOBUFS;
1035                                 break;
1036                         }
1037                         m->m_len = sopt->sopt_valsize;
1038                         error = sooptcopyin(sopt, mtod(m, char *), m->m_len,
1039                                             m->m_len);
1040                         if (error) {
1041                                 m_free(m);
1042                                 break;
1043                         }
1044                         INP_WLOCK(inp);
1045                         error = ip_pcbopts(inp, sopt->sopt_name, m);
1046                         INP_WUNLOCK(inp);
1047                         return (error);
1048                 }
1049
1050                 case IP_BINDANY:
1051                         if (sopt->sopt_td != NULL) {
1052                                 error = priv_check(sopt->sopt_td,
1053                                     PRIV_NETINET_BINDANY);
1054                                 if (error)
1055                                         break;
1056                         }
1057                         /* FALLTHROUGH */
1058                 case IP_BINDMULTI:
1059 #ifdef  RSS
1060                 case IP_RSS_LISTEN_BUCKET:
1061 #endif
1062                 case IP_TOS:
1063                 case IP_TTL:
1064                 case IP_MINTTL:
1065                 case IP_RECVOPTS:
1066                 case IP_RECVRETOPTS:
1067                 case IP_ORIGDSTADDR:
1068                 case IP_RECVDSTADDR:
1069                 case IP_RECVTTL:
1070                 case IP_RECVIF:
1071                 case IP_ONESBCAST:
1072                 case IP_DONTFRAG:
1073                 case IP_RECVTOS:
1074                 case IP_RECVFLOWID:
1075 #ifdef  RSS
1076                 case IP_RECVRSSBUCKETID:
1077 #endif
1078                         error = sooptcopyin(sopt, &optval, sizeof optval,
1079                                             sizeof optval);
1080                         if (error)
1081                                 break;
1082
1083                         switch (sopt->sopt_name) {
1084                         case IP_TOS:
1085                                 inp->inp_ip_tos = optval;
1086                                 break;
1087
1088                         case IP_TTL:
1089                                 inp->inp_ip_ttl = optval;
1090                                 break;
1091
1092                         case IP_MINTTL:
1093                                 if (optval >= 0 && optval <= MAXTTL)
1094                                         inp->inp_ip_minttl = optval;
1095                                 else
1096                                         error = EINVAL;
1097                                 break;
1098
1099 #define OPTSET(bit) do {                                                \
1100         INP_WLOCK(inp);                                                 \
1101         if (optval)                                                     \
1102                 inp->inp_flags |= bit;                                  \
1103         else                                                            \
1104                 inp->inp_flags &= ~bit;                                 \
1105         INP_WUNLOCK(inp);                                               \
1106 } while (0)
1107
1108 #define OPTSET2(bit, val) do {                                          \
1109         INP_WLOCK(inp);                                                 \
1110         if (val)                                                        \
1111                 inp->inp_flags2 |= bit;                                 \
1112         else                                                            \
1113                 inp->inp_flags2 &= ~bit;                                \
1114         INP_WUNLOCK(inp);                                               \
1115 } while (0)
1116
1117                         case IP_RECVOPTS:
1118                                 OPTSET(INP_RECVOPTS);
1119                                 break;
1120
1121                         case IP_RECVRETOPTS:
1122                                 OPTSET(INP_RECVRETOPTS);
1123                                 break;
1124
1125                         case IP_RECVDSTADDR:
1126                                 OPTSET(INP_RECVDSTADDR);
1127                                 break;
1128
1129                         case IP_ORIGDSTADDR:
1130                                 OPTSET2(INP_ORIGDSTADDR, optval);
1131                                 break;
1132
1133                         case IP_RECVTTL:
1134                                 OPTSET(INP_RECVTTL);
1135                                 break;
1136
1137                         case IP_RECVIF:
1138                                 OPTSET(INP_RECVIF);
1139                                 break;
1140
1141                         case IP_ONESBCAST:
1142                                 OPTSET(INP_ONESBCAST);
1143                                 break;
1144                         case IP_DONTFRAG:
1145                                 OPTSET(INP_DONTFRAG);
1146                                 break;
1147                         case IP_BINDANY:
1148                                 OPTSET(INP_BINDANY);
1149                                 break;
1150                         case IP_RECVTOS:
1151                                 OPTSET(INP_RECVTOS);
1152                                 break;
1153                         case IP_BINDMULTI:
1154                                 OPTSET2(INP_BINDMULTI, optval);
1155                                 break;
1156                         case IP_RECVFLOWID:
1157                                 OPTSET2(INP_RECVFLOWID, optval);
1158                                 break;
1159 #ifdef  RSS
1160                         case IP_RSS_LISTEN_BUCKET:
1161                                 if ((optval >= 0) &&
1162                                     (optval < rss_getnumbuckets())) {
1163                                         inp->inp_rss_listen_bucket = optval;
1164                                         OPTSET2(INP_RSS_BUCKET_SET, 1);
1165                                 } else {
1166                                         error = EINVAL;
1167                                 }
1168                                 break;
1169                         case IP_RECVRSSBUCKETID:
1170                                 OPTSET2(INP_RECVRSSBUCKETID, optval);
1171                                 break;
1172 #endif
1173                         }
1174                         break;
1175 #undef OPTSET
1176 #undef OPTSET2
1177
1178                 /*
1179                  * Multicast socket options are processed by the in_mcast
1180                  * module.
1181                  */
1182                 case IP_MULTICAST_IF:
1183                 case IP_MULTICAST_VIF:
1184                 case IP_MULTICAST_TTL:
1185                 case IP_MULTICAST_LOOP:
1186                 case IP_ADD_MEMBERSHIP:
1187                 case IP_DROP_MEMBERSHIP:
1188                 case IP_ADD_SOURCE_MEMBERSHIP:
1189                 case IP_DROP_SOURCE_MEMBERSHIP:
1190                 case IP_BLOCK_SOURCE:
1191                 case IP_UNBLOCK_SOURCE:
1192                 case IP_MSFILTER:
1193                 case MCAST_JOIN_GROUP:
1194                 case MCAST_LEAVE_GROUP:
1195                 case MCAST_JOIN_SOURCE_GROUP:
1196                 case MCAST_LEAVE_SOURCE_GROUP:
1197                 case MCAST_BLOCK_SOURCE:
1198                 case MCAST_UNBLOCK_SOURCE:
1199                         error = inp_setmoptions(inp, sopt);
1200                         break;
1201
1202                 case IP_PORTRANGE:
1203                         error = sooptcopyin(sopt, &optval, sizeof optval,
1204                                             sizeof optval);
1205                         if (error)
1206                                 break;
1207
1208                         INP_WLOCK(inp);
1209                         switch (optval) {
1210                         case IP_PORTRANGE_DEFAULT:
1211                                 inp->inp_flags &= ~(INP_LOWPORT);
1212                                 inp->inp_flags &= ~(INP_HIGHPORT);
1213                                 break;
1214
1215                         case IP_PORTRANGE_HIGH:
1216                                 inp->inp_flags &= ~(INP_LOWPORT);
1217                                 inp->inp_flags |= INP_HIGHPORT;
1218                                 break;
1219
1220                         case IP_PORTRANGE_LOW:
1221                                 inp->inp_flags &= ~(INP_HIGHPORT);
1222                                 inp->inp_flags |= INP_LOWPORT;
1223                                 break;
1224
1225                         default:
1226                                 error = EINVAL;
1227                                 break;
1228                         }
1229                         INP_WUNLOCK(inp);
1230                         break;
1231
1232 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1233                 case IP_IPSEC_POLICY:
1234                         if (IPSEC_ENABLED(ipv4)) {
1235                                 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1236                                 break;
1237                         }
1238                         /* FALLTHROUGH */
1239 #endif /* IPSEC */
1240
1241                 default:
1242                         error = ENOPROTOOPT;
1243                         break;
1244                 }
1245                 break;
1246
1247         case SOPT_GET:
1248                 switch (sopt->sopt_name) {
1249                 case IP_OPTIONS:
1250                 case IP_RETOPTS:
1251                         if (inp->inp_options)
1252                                 error = sooptcopyout(sopt,
1253                                                      mtod(inp->inp_options,
1254                                                           char *),
1255                                                      inp->inp_options->m_len);
1256                         else
1257                                 sopt->sopt_valsize = 0;
1258                         break;
1259
1260                 case IP_TOS:
1261                 case IP_TTL:
1262                 case IP_MINTTL:
1263                 case IP_RECVOPTS:
1264                 case IP_RECVRETOPTS:
1265                 case IP_ORIGDSTADDR:
1266                 case IP_RECVDSTADDR:
1267                 case IP_RECVTTL:
1268                 case IP_RECVIF:
1269                 case IP_PORTRANGE:
1270                 case IP_ONESBCAST:
1271                 case IP_DONTFRAG:
1272                 case IP_BINDANY:
1273                 case IP_RECVTOS:
1274                 case IP_BINDMULTI:
1275                 case IP_FLOWID:
1276                 case IP_FLOWTYPE:
1277                 case IP_RECVFLOWID:
1278 #ifdef  RSS
1279                 case IP_RSSBUCKETID:
1280                 case IP_RECVRSSBUCKETID:
1281 #endif
1282                         switch (sopt->sopt_name) {
1283
1284                         case IP_TOS:
1285                                 optval = inp->inp_ip_tos;
1286                                 break;
1287
1288                         case IP_TTL:
1289                                 optval = inp->inp_ip_ttl;
1290                                 break;
1291
1292                         case IP_MINTTL:
1293                                 optval = inp->inp_ip_minttl;
1294                                 break;
1295
1296 #define OPTBIT(bit)     (inp->inp_flags & bit ? 1 : 0)
1297 #define OPTBIT2(bit)    (inp->inp_flags2 & bit ? 1 : 0)
1298
1299                         case IP_RECVOPTS:
1300                                 optval = OPTBIT(INP_RECVOPTS);
1301                                 break;
1302
1303                         case IP_RECVRETOPTS:
1304                                 optval = OPTBIT(INP_RECVRETOPTS);
1305                                 break;
1306
1307                         case IP_RECVDSTADDR:
1308                                 optval = OPTBIT(INP_RECVDSTADDR);
1309                                 break;
1310
1311                         case IP_ORIGDSTADDR:
1312                                 optval = OPTBIT2(INP_ORIGDSTADDR);
1313                                 break;
1314
1315                         case IP_RECVTTL:
1316                                 optval = OPTBIT(INP_RECVTTL);
1317                                 break;
1318
1319                         case IP_RECVIF:
1320                                 optval = OPTBIT(INP_RECVIF);
1321                                 break;
1322
1323                         case IP_PORTRANGE:
1324                                 if (inp->inp_flags & INP_HIGHPORT)
1325                                         optval = IP_PORTRANGE_HIGH;
1326                                 else if (inp->inp_flags & INP_LOWPORT)
1327                                         optval = IP_PORTRANGE_LOW;
1328                                 else
1329                                         optval = 0;
1330                                 break;
1331
1332                         case IP_ONESBCAST:
1333                                 optval = OPTBIT(INP_ONESBCAST);
1334                                 break;
1335                         case IP_DONTFRAG:
1336                                 optval = OPTBIT(INP_DONTFRAG);
1337                                 break;
1338                         case IP_BINDANY:
1339                                 optval = OPTBIT(INP_BINDANY);
1340                                 break;
1341                         case IP_RECVTOS:
1342                                 optval = OPTBIT(INP_RECVTOS);
1343                                 break;
1344                         case IP_FLOWID:
1345                                 optval = inp->inp_flowid;
1346                                 break;
1347                         case IP_FLOWTYPE:
1348                                 optval = inp->inp_flowtype;
1349                                 break;
1350                         case IP_RECVFLOWID:
1351                                 optval = OPTBIT2(INP_RECVFLOWID);
1352                                 break;
1353 #ifdef  RSS
1354                         case IP_RSSBUCKETID:
1355                                 retval = rss_hash2bucket(inp->inp_flowid,
1356                                     inp->inp_flowtype,
1357                                     &rss_bucket);
1358                                 if (retval == 0)
1359                                         optval = rss_bucket;
1360                                 else
1361                                         error = EINVAL;
1362                                 break;
1363                         case IP_RECVRSSBUCKETID:
1364                                 optval = OPTBIT2(INP_RECVRSSBUCKETID);
1365                                 break;
1366 #endif
1367                         case IP_BINDMULTI:
1368                                 optval = OPTBIT2(INP_BINDMULTI);
1369                                 break;
1370                         }
1371                         error = sooptcopyout(sopt, &optval, sizeof optval);
1372                         break;
1373
1374                 /*
1375                  * Multicast socket options are processed by the in_mcast
1376                  * module.
1377                  */
1378                 case IP_MULTICAST_IF:
1379                 case IP_MULTICAST_VIF:
1380                 case IP_MULTICAST_TTL:
1381                 case IP_MULTICAST_LOOP:
1382                 case IP_MSFILTER:
1383                         error = inp_getmoptions(inp, sopt);
1384                         break;
1385
1386 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1387                 case IP_IPSEC_POLICY:
1388                         if (IPSEC_ENABLED(ipv4)) {
1389                                 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1390                                 break;
1391                         }
1392                         /* FALLTHROUGH */
1393 #endif /* IPSEC */
1394
1395                 default:
1396                         error = ENOPROTOOPT;
1397                         break;
1398                 }
1399                 break;
1400         }
1401         return (error);
1402 }
1403
1404 /*
1405  * Routine called from ip_output() to loop back a copy of an IP multicast
1406  * packet to the input queue of a specified interface.  Note that this
1407  * calls the output routine of the loopback "driver", but with an interface
1408  * pointer that might NOT be a loopback interface -- evil, but easier than
1409  * replicating that code here.
1410  */
1411 static void
1412 ip_mloopback(struct ifnet *ifp, const struct mbuf *m, int hlen)
1413 {
1414         struct ip *ip;
1415         struct mbuf *copym;
1416
1417         /*
1418          * Make a deep copy of the packet because we're going to
1419          * modify the pack in order to generate checksums.
1420          */
1421         copym = m_dup(m, M_NOWAIT);
1422         if (copym != NULL && (!M_WRITABLE(copym) || copym->m_len < hlen))
1423                 copym = m_pullup(copym, hlen);
1424         if (copym != NULL) {
1425                 /* If needed, compute the checksum and mark it as valid. */
1426                 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
1427                         in_delayed_cksum(copym);
1428                         copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1429                         copym->m_pkthdr.csum_flags |=
1430                             CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1431                         copym->m_pkthdr.csum_data = 0xffff;
1432                 }
1433                 /*
1434                  * We don't bother to fragment if the IP length is greater
1435                  * than the interface's MTU.  Can this possibly matter?
1436                  */
1437                 ip = mtod(copym, struct ip *);
1438                 ip->ip_sum = 0;
1439                 ip->ip_sum = in_cksum(copym, hlen);
1440                 if_simloop(ifp, copym, AF_INET, 0);
1441         }
1442 }