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_ipsec.h"
  39 #include "opt_kern_tls.h"
  40 #include "opt_mbuf_stress_test.h"
  41 #include "opt_mpath.h"
  42 #include "opt_ratelimit.h"
  43 #include "opt_route.h"
  44 #include "opt_rss.h"
  45 #include "opt_sctp.h"
  46
  47 #include <sys/param.h>
  48 #include <sys/systm.h>
  49 #include <sys/kernel.h>
  50 #include <sys/ktls.h>
  51 #include <sys/lock.h>
  52 #include <sys/malloc.h>
  53 #include <sys/mbuf.h>
  54 #include <sys/priv.h>
  55 #include <sys/proc.h>
  56 #include <sys/protosw.h>
  57 #include <sys/rmlock.h>
  58 #include <sys/sdt.h>
  59 #include <sys/socket.h>
  60 #include <sys/socketvar.h>
  61 #include <sys/sysctl.h>
  62 #include <sys/ucred.h>
  63
  64 #include <net/if.h>
  65 #include <net/if_var.h>
  66 #include <net/if_llatbl.h>
  67 #include <net/netisr.h>
  68 #include <net/pfil.h>
  69 #include <net/route.h>
  70 #ifdef RADIX_MPATH
  71 #include <net/radix_mpath.h>
  72 #endif
  73 #include <net/rss_config.h>
  74 #include <net/vnet.h>
  75
  76 #include <netinet/in.h>
  77 #include <netinet/in_fib.h>
  78 #include <netinet/in_kdtrace.h>
  79 #include <netinet/in_systm.h>
  80 #include <netinet/ip.h>
  81 #include <netinet/in_pcb.h>
  82 #include <netinet/in_rss.h>
  83 #include <netinet/in_var.h>
  84 #include <netinet/ip_var.h>
  85 #include <netinet/ip_options.h>
  86
  87 #include <netinet/udp.h>
  88 #include <netinet/udp_var.h>
  89
  90 #ifdef SCTP
  91 #include <netinet/sctp.h>
  92 #include <netinet/sctp_crc32.h>
  93 #endif
  94
  95 #include <netipsec/ipsec_support.h>
  96
  97 #include <machine/in_cksum.h>
  98
  99 #include <security/mac/mac_framework.h>
 100
 101 #ifdef MBUF_STRESS_TEST
 102 static int mbuf_frag_size = 0;
 103 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
 104         &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
 105 #endif
 106
 107 static void     ip_mloopback(struct ifnet *, const struct mbuf *, int);
 108
 109
 110 extern int in_mcast_loop;
 111 extern  struct protosw inetsw[];
 112
 113 static inline int
 114 ip_output_pfil(struct mbuf **mp, struct ifnet *ifp, int flags,
 115     struct inpcb *inp, struct sockaddr_in *dst, int *fibnum, int *error)
 116 {
 117         struct m_tag *fwd_tag = NULL;
 118         struct mbuf *m;
 119         struct in_addr odst;
 120         struct ip *ip;
 121         int pflags = PFIL_OUT;
 122
 123         if (flags & IP_FORWARDING)
 124                 pflags |= PFIL_FWD;
 125
 126         m = *mp;
 127         ip = mtod(m, struct ip *);
 128
 129         /* Run through list of hooks for output packets. */
 130         odst.s_addr = ip->ip_dst.s_addr;
 131         switch (pfil_run_hooks(V_inet_pfil_head, mp, ifp, pflags, inp)) {
 132         case PFIL_DROPPED:
 133                 *error = EACCES;
 134                 /* FALLTHROUGH */
 135         case PFIL_CONSUMED:
 136                 return 1; /* Finished */
 137         case PFIL_PASS:
 138                 *error = 0;
 139         }
 140         m = *mp;
 141         ip = mtod(m, struct ip *);
 142
 143         /* See if destination IP address was changed by packet filter. */
 144         if (odst.s_addr != ip->ip_dst.s_addr) {
 145                 m->m_flags |= M_SKIP_FIREWALL;
 146                 /* If destination is now ourself drop to ip_input(). */
 147                 if (in_localip(ip->ip_dst)) {
 148                         m->m_flags |= M_FASTFWD_OURS;
 149                         if (m->m_pkthdr.rcvif == NULL)
 150                                 m->m_pkthdr.rcvif = V_loif;
 151                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 152                                 m->m_pkthdr.csum_flags |=
 153                                         CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
 154                                 m->m_pkthdr.csum_data = 0xffff;
 155                         }
 156                         m->m_pkthdr.csum_flags |=
 157                                 CSUM_IP_CHECKED | CSUM_IP_VALID;
 158 #ifdef SCTP
 159                         if (m->m_pkthdr.csum_flags & CSUM_SCTP)
 160                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 161 #endif
 162                         *error = netisr_queue(NETISR_IP, m);
 163                         return 1; /* Finished */
 164                 }
 165
 166                 bzero(dst, sizeof(*dst));
 167                 dst->sin_family = AF_INET;
 168                 dst->sin_len = sizeof(*dst);
 169                 dst->sin_addr = ip->ip_dst;
 170
 171                 return -1; /* Reloop */
 172         }
 173         /* See if fib was changed by packet filter. */
 174         if ((*fibnum) != M_GETFIB(m)) {
 175                 m->m_flags |= M_SKIP_FIREWALL;
 176                 *fibnum = M_GETFIB(m);
 177                 return -1; /* Reloop for FIB change */
 178         }
 179
 180         /* See if local, if yes, send it to netisr with IP_FASTFWD_OURS. */
 181         if (m->m_flags & M_FASTFWD_OURS) {
 182                 if (m->m_pkthdr.rcvif == NULL)
 183                         m->m_pkthdr.rcvif = V_loif;
 184                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 185                         m->m_pkthdr.csum_flags |=
 186                                 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
 187                         m->m_pkthdr.csum_data = 0xffff;
 188                 }
 189 #ifdef SCTP
 190                 if (m->m_pkthdr.csum_flags & CSUM_SCTP)
 191                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 192 #endif
 193                 m->m_pkthdr.csum_flags |=
 194                         CSUM_IP_CHECKED | CSUM_IP_VALID;
 195
 196                 *error = netisr_queue(NETISR_IP, m);
 197                 return 1; /* Finished */
 198         }
 199         /* Or forward to some other address? */
 200         if ((m->m_flags & M_IP_NEXTHOP) &&
 201             ((fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL)) {
 202                 bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in));
 203                 m->m_flags |= M_SKIP_FIREWALL;
 204                 m->m_flags &= ~M_IP_NEXTHOP;
 205                 m_tag_delete(m, fwd_tag);
 206
 207                 return -1; /* Reloop for CHANGE of dst */
 208         }
 209
 210         return 0;
 211 }
 212
 213 static int
 214 ip_output_send(struct inpcb *inp, struct ifnet *ifp, struct mbuf *m,
 215     const struct sockaddr_in *gw, struct route *ro, bool stamp_tag)
 216 {
 217 #ifdef KERN_TLS
 218         struct ktls_session *tls = NULL;
 219 #endif
 220         struct m_snd_tag *mst;
 221         int error;
 222
 223         MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0);
 224         mst = NULL;
 225
 226 #ifdef KERN_TLS
 227         /*
 228          * If this is an unencrypted TLS record, save a reference to
 229          * the record.  This local reference is used to call
 230          * ktls_output_eagain after the mbuf has been freed (thus
 231          * dropping the mbuf's reference) in if_output.
 232          */
 233         if (m->m_next != NULL && mbuf_has_tls_session(m->m_next)) {
 234                 tls = ktls_hold(m->m_next->m_ext.ext_pgs->tls);
 235                 mst = tls->snd_tag;
 236
 237                 /*
 238                  * If a TLS session doesn't have a valid tag, it must
 239                  * have had an earlier ifp mismatch, so drop this
 240                  * packet.
 241                  */
 242                 if (mst == NULL) {
 243                         error = EAGAIN;
 244                         goto done;
 245                 }
 246         }
 247 #endif
 248 #ifdef RATELIMIT
 249         if (inp != NULL && mst == NULL) {
 250                 if ((inp->inp_flags2 & INP_RATE_LIMIT_CHANGED) != 0 ||
 251                     (inp->inp_snd_tag != NULL &&
 252                     inp->inp_snd_tag->ifp != ifp))
 253                         in_pcboutput_txrtlmt(inp, ifp, m);
 254
 255                 if (inp->inp_snd_tag != NULL)
 256                         mst = inp->inp_snd_tag;
 257         }
 258 #endif
 259         if (stamp_tag && mst != NULL) {
 260                 KASSERT(m->m_pkthdr.rcvif == NULL,
 261                     ("trying to add a send tag to a forwarded packet"));
 262                 if (mst->ifp != ifp) {
 263                         error = EAGAIN;
 264                         goto done;
 265                 }
 266
 267                 /* stamp send tag on mbuf */
 268                 m->m_pkthdr.snd_tag = m_snd_tag_ref(mst);
 269                 m->m_pkthdr.csum_flags |= CSUM_SND_TAG;
 270         }
 271
 272         error = (*ifp->if_output)(ifp, m, (const struct sockaddr *)gw, ro);
 273
 274 done:
 275         /* Check for route change invalidating send tags. */
 276 #ifdef KERN_TLS
 277         if (tls != NULL) {
 278                 if (error == EAGAIN)
 279                         error = ktls_output_eagain(inp, tls);
 280                 ktls_free(tls);
 281         }
 282 #endif
 283 #ifdef RATELIMIT
 284         if (error == EAGAIN)
 285                 in_pcboutput_eagain(inp);
 286 #endif
 287         return (error);
 288 }
 289
 290 /*
 291  * IP output.  The packet in mbuf chain m contains a skeletal IP
 292  * header (with len, off, ttl, proto, tos, src, dst).
 293  * The mbuf chain containing the packet will be freed.
 294  * The mbuf opt, if present, will not be freed.
 295  * If route ro is present and has ro_rt initialized, route lookup would be
 296  * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
 297  * then result of route lookup is stored in ro->ro_rt.
 298  *
 299  * In the IP forwarding case, the packet will arrive with options already
 300  * inserted, so must have a NULL opt pointer.
 301  */
 302 int
 303 ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
 304     struct ip_moptions *imo, struct inpcb *inp)
 305 {
 306         struct rm_priotracker in_ifa_tracker;
 307         struct ip *ip;
 308         struct ifnet *ifp = NULL;       /* keep compiler happy */
 309         struct mbuf *m0;
 310         int hlen = sizeof (struct ip);
 311         int mtu;
 312         int error = 0;
 313         struct sockaddr_in *dst, sin;
 314         const struct sockaddr_in *gw;
 315         struct in_ifaddr *ia;
 316         struct in_addr src;
 317         int isbroadcast;
 318         uint16_t ip_len, ip_off;
 319         uint32_t fibnum;
 320 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 321         int no_route_but_check_spd = 0;
 322 #endif
 323
 324         M_ASSERTPKTHDR(m);
 325         NET_EPOCH_ASSERT();
 326
 327         if (inp != NULL) {
 328                 INP_LOCK_ASSERT(inp);
 329                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 330                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 331                         m->m_pkthdr.flowid = inp->inp_flowid;
 332                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 333                 }
 334 #ifdef NUMA
 335                 m->m_pkthdr.numa_domain = inp->inp_numa_domain;
 336 #endif
 337         }
 338
 339         if (opt) {
 340                 int len = 0;
 341                 m = ip_insertoptions(m, opt, &len);
 342                 if (len != 0)
 343                         hlen = len; /* ip->ip_hl is updated above */
 344         }
 345         ip = mtod(m, struct ip *);
 346         ip_len = ntohs(ip->ip_len);
 347         ip_off = ntohs(ip->ip_off);
 348
 349         if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) {
 350                 ip->ip_v = IPVERSION;
 351                 ip->ip_hl = hlen >> 2;
 352                 ip_fillid(ip);
 353         } else {
 354                 /* Header already set, fetch hlen from there */
 355                 hlen = ip->ip_hl << 2;
 356         }
 357         if ((flags & IP_FORWARDING) == 0)
 358                 IPSTAT_INC(ips_localout);
 359
 360         /*
 361          * dst/gw handling:
 362          *
 363          * gw is readonly but can point either to dst OR rt_gateway,
 364          * therefore we need restore gw if we're redoing lookup.
 365          */
 366         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 367         if (ro != NULL)
 368                 dst = (struct sockaddr_in *)&ro->ro_dst;
 369         else
 370                 dst = &sin;
 371         if (ro == NULL || ro->ro_rt == NULL) {
 372                 bzero(dst, sizeof(*dst));
 373                 dst->sin_family = AF_INET;
 374                 dst->sin_len = sizeof(*dst);
 375                 dst->sin_addr = ip->ip_dst;
 376         }
 377         gw = dst;
 378 again:
 379         /*
 380          * Validate route against routing table additions;
 381          * a better/more specific route might have been added.
 382          */
 383         if (inp != NULL && ro != NULL && ro->ro_rt != NULL)
 384                 RT_VALIDATE(ro, &inp->inp_rt_cookie, fibnum);
 385         /*
 386          * If there is a cached route,
 387          * check that it is to the same destination
 388          * and is still up.  If not, free it and try again.
 389          * The address family should also be checked in case of sharing the
 390          * cache with IPv6.
 391          * Also check whether routing cache needs invalidation.
 392          */
 393         if (ro != NULL && ro->ro_rt != NULL &&
 394             ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
 395             ro->ro_rt->rt_ifp == NULL || !RT_LINK_IS_UP(ro->ro_rt->rt_ifp) ||
 396             dst->sin_family != AF_INET ||
 397             dst->sin_addr.s_addr != ip->ip_dst.s_addr))
 398                 RO_INVALIDATE_CACHE(ro);
 399         ia = NULL;
 400         /*
 401          * If routing to interface only, short circuit routing lookup.
 402          * The use of an all-ones broadcast address implies this; an
 403          * interface is specified by the broadcast address of an interface,
 404          * or the destination address of a ptp interface.
 405          */
 406         if (flags & IP_SENDONES) {
 407                 if ((ia = ifatoia(ifa_ifwithbroadaddr(sintosa(dst),
 408                                                       M_GETFIB(m)))) == NULL &&
 409                     (ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
 410                                                     M_GETFIB(m)))) == NULL) {
 411                         IPSTAT_INC(ips_noroute);
 412                         error = ENETUNREACH;
 413                         goto bad;
 414                 }
 415                 ip->ip_dst.s_addr = INADDR_BROADCAST;
 416                 dst->sin_addr = ip->ip_dst;
 417                 ifp = ia->ia_ifp;
 418                 mtu = ifp->if_mtu;
 419                 ip->ip_ttl = 1;
 420                 isbroadcast = 1;
 421                 src = IA_SIN(ia)->sin_addr;
 422         } else if (flags & IP_ROUTETOIF) {
 423                 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
 424                                                     M_GETFIB(m)))) == NULL &&
 425                     (ia = ifatoia(ifa_ifwithnet(sintosa(dst), 0,
 426                                                 M_GETFIB(m)))) == NULL) {
 427                         IPSTAT_INC(ips_noroute);
 428                         error = ENETUNREACH;
 429                         goto bad;
 430                 }
 431                 ifp = ia->ia_ifp;
 432                 mtu = ifp->if_mtu;
 433                 ip->ip_ttl = 1;
 434                 isbroadcast = ifp->if_flags & IFF_BROADCAST ?
 435                     in_ifaddr_broadcast(dst->sin_addr, ia) : 0;
 436                 src = IA_SIN(ia)->sin_addr;
 437         } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
 438             imo != NULL && imo->imo_multicast_ifp != NULL) {
 439                 /*
 440                  * Bypass the normal routing lookup for multicast
 441                  * packets if the interface is specified.
 442                  */
 443                 ifp = imo->imo_multicast_ifp;
 444                 mtu = ifp->if_mtu;
 445                 IFP_TO_IA(ifp, ia, &in_ifa_tracker);
 446                 isbroadcast = 0;        /* fool gcc */
 447                 /* Interface may have no addresses. */
 448                 if (ia != NULL)
 449                         src = IA_SIN(ia)->sin_addr;
 450                 else
 451                         src.s_addr = INADDR_ANY;
 452         } else if (ro != NULL) {
 453                 if (ro->ro_rt == NULL) {
 454                         /*
 455                          * We want to do any cloning requested by the link
 456                          * layer, as this is probably required in all cases
 457                          * for correct operation (as it is for ARP).
 458                          */
 459 #ifdef RADIX_MPATH
 460                         rtalloc_mpath_fib(ro,
 461                             ntohl(ip->ip_src.s_addr ^ ip->ip_dst.s_addr),
 462                             fibnum);
 463 #else
 464                         in_rtalloc_ign(ro, 0, fibnum);
 465 #endif
 466                         if (ro->ro_rt == NULL ||
 467                             (ro->ro_rt->rt_flags & RTF_UP) == 0 ||
 468                             ro->ro_rt->rt_ifp == NULL ||
 469                             !RT_LINK_IS_UP(ro->ro_rt->rt_ifp)) {
 470 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 471                                 /*
 472                                  * There is no route for this packet, but it is
 473                                  * possible that a matching SPD entry exists.
 474                                  */
 475                                 no_route_but_check_spd = 1;
 476                                 mtu = 0; /* Silence GCC warning. */
 477                                 goto sendit;
 478 #endif
 479                                 IPSTAT_INC(ips_noroute);
 480                                 error = EHOSTUNREACH;
 481                                 goto bad;
 482                         }
 483                 }
 484                 ia = ifatoia(ro->ro_rt->rt_ifa);
 485                 ifp = ro->ro_rt->rt_ifp;
 486                 counter_u64_add(ro->ro_rt->rt_pksent, 1);
 487                 rt_update_ro_flags(ro);
 488                 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
 489                         gw = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
 490                 if (ro->ro_rt->rt_flags & RTF_HOST)
 491                         isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST);
 492                 else if (ifp->if_flags & IFF_BROADCAST)
 493                         isbroadcast = in_ifaddr_broadcast(gw->sin_addr, ia);
 494                 else
 495                         isbroadcast = 0;
 496                 if (ro->ro_rt->rt_flags & RTF_HOST)
 497                         mtu = ro->ro_rt->rt_mtu;
 498                 else
 499                         mtu = ifp->if_mtu;
 500                 src = IA_SIN(ia)->sin_addr;
 501         } else {
 502                 struct nhop4_extended nh;
 503
 504                 bzero(&nh, sizeof(nh));
 505                 if (fib4_lookup_nh_ext(M_GETFIB(m), ip->ip_dst, 0, 0, &nh) !=
 506                     0) {
 507 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 508                         /*
 509                          * There is no route for this packet, but it is
 510                          * possible that a matching SPD entry exists.
 511                          */
 512                         no_route_but_check_spd = 1;
 513                         mtu = 0; /* Silence GCC warning. */
 514                         goto sendit;
 515 #endif
 516                         IPSTAT_INC(ips_noroute);
 517                         error = EHOSTUNREACH;
 518                         goto bad;
 519                 }
 520                 ifp = nh.nh_ifp;
 521                 mtu = nh.nh_mtu;
 522                 /*
 523                  * We are rewriting here dst to be gw actually, contradicting
 524                  * comment at the beginning of the function. However, in this
 525                  * case we are always dealing with on stack dst.
 526                  * In case if pfil(9) sends us back to beginning of the
 527                  * function, the dst would be rewritten by ip_output_pfil().
 528                  */
 529                 MPASS(dst == &sin);
 530                 dst->sin_addr = nh.nh_addr;
 531                 ia = nh.nh_ia;
 532                 src = nh.nh_src;
 533                 isbroadcast = (((nh.nh_flags & (NHF_HOST | NHF_BROADCAST)) ==
 534                     (NHF_HOST | NHF_BROADCAST)) ||
 535                     ((ifp->if_flags & IFF_BROADCAST) &&
 536                     in_ifaddr_broadcast(dst->sin_addr, ia)));
 537         }
 538
 539         /* Catch a possible divide by zero later. */
 540         KASSERT(mtu > 0, ("%s: mtu %d <= 0, ro=%p (rt_flags=0x%08x) ifp=%p",
 541             __func__, mtu, ro,
 542             (ro != NULL && ro->ro_rt != NULL) ? ro->ro_rt->rt_flags : 0, ifp));
 543
 544         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
 545                 m->m_flags |= M_MCAST;
 546                 /*
 547                  * IP destination address is multicast.  Make sure "gw"
 548                  * still points to the address in "ro".  (It may have been
 549                  * changed to point to a gateway address, above.)
 550                  */
 551                 gw = dst;
 552                 /*
 553                  * See if the caller provided any multicast options
 554                  */
 555                 if (imo != NULL) {
 556                         ip->ip_ttl = imo->imo_multicast_ttl;
 557                         if (imo->imo_multicast_vif != -1)
 558                                 ip->ip_src.s_addr =
 559                                     ip_mcast_src ?
 560                                     ip_mcast_src(imo->imo_multicast_vif) :
 561                                     INADDR_ANY;
 562                 } else
 563                         ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
 564                 /*
 565                  * Confirm that the outgoing interface supports multicast.
 566                  */
 567                 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
 568                         if ((ifp->if_flags & IFF_MULTICAST) == 0) {
 569                                 IPSTAT_INC(ips_noroute);
 570                                 error = ENETUNREACH;
 571                                 goto bad;
 572                         }
 573                 }
 574                 /*
 575                  * If source address not specified yet, use address
 576                  * of outgoing interface.
 577                  */
 578                 if (ip->ip_src.s_addr == INADDR_ANY)
 579                         ip->ip_src = src;
 580
 581                 if ((imo == NULL && in_mcast_loop) ||
 582                     (imo && imo->imo_multicast_loop)) {
 583                         /*
 584                          * Loop back multicast datagram if not expressly
 585                          * forbidden to do so, even if we are not a member
 586                          * of the group; ip_input() will filter it later,
 587                          * thus deferring a hash lookup and mutex acquisition
 588                          * at the expense of a cheap copy using m_copym().
 589                          */
 590                         ip_mloopback(ifp, m, hlen);
 591                 } else {
 592                         /*
 593                          * If we are acting as a multicast router, perform
 594                          * multicast forwarding as if the packet had just
 595                          * arrived on the interface to which we are about
 596                          * to send.  The multicast forwarding function
 597                          * recursively calls this function, using the
 598                          * IP_FORWARDING flag to prevent infinite recursion.
 599                          *
 600                          * Multicasts that are looped back by ip_mloopback(),
 601                          * above, will be forwarded by the ip_input() routine,
 602                          * if necessary.
 603                          */
 604                         if (V_ip_mrouter && (flags & IP_FORWARDING) == 0) {
 605                                 /*
 606                                  * If rsvp daemon is not running, do not
 607                                  * set ip_moptions. This ensures that the packet
 608                                  * is multicast and not just sent down one link
 609                                  * as prescribed by rsvpd.
 610                                  */
 611                                 if (!V_rsvp_on)
 612                                         imo = NULL;
 613                                 if (ip_mforward &&
 614                                     ip_mforward(ip, ifp, m, imo) != 0) {
 615                                         m_freem(m);
 616                                         goto done;
 617                                 }
 618                         }
 619                 }
 620
 621                 /*
 622                  * Multicasts with a time-to-live of zero may be looped-
 623                  * back, above, but must not be transmitted on a network.
 624                  * Also, multicasts addressed to the loopback interface
 625                  * are not sent -- the above call to ip_mloopback() will
 626                  * loop back a copy. ip_input() will drop the copy if
 627                  * this host does not belong to the destination group on
 628                  * the loopback interface.
 629                  */
 630                 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
 631                         m_freem(m);
 632                         goto done;
 633                 }
 634
 635                 goto sendit;
 636         }
 637
 638         /*
 639          * If the source address is not specified yet, use the address
 640          * of the outoing interface.
 641          */
 642         if (ip->ip_src.s_addr == INADDR_ANY)
 643                 ip->ip_src = src;
 644
 645         /*
 646          * Look for broadcast address and
 647          * verify user is allowed to send
 648          * such a packet.
 649          */
 650         if (isbroadcast) {
 651                 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
 652                         error = EADDRNOTAVAIL;
 653                         goto bad;
 654                 }
 655                 if ((flags & IP_ALLOWBROADCAST) == 0) {
 656                         error = EACCES;
 657                         goto bad;
 658                 }
 659                 /* don't allow broadcast messages to be fragmented */
 660                 if (ip_len > mtu) {
 661                         error = EMSGSIZE;
 662                         goto bad;
 663                 }
 664                 m->m_flags |= M_BCAST;
 665         } else {
 666                 m->m_flags &= ~M_BCAST;
 667         }
 668
 669 sendit:
 670 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 671         if (IPSEC_ENABLED(ipv4)) {
 672                 if ((error = IPSEC_OUTPUT(ipv4, m, inp)) != 0) {
 673                         if (error == EINPROGRESS)
 674                                 error = 0;
 675                         goto done;
 676                 }
 677         }
 678         /*
 679          * Check if there was a route for this packet; return error if not.
 680          */
 681         if (no_route_but_check_spd) {
 682                 IPSTAT_INC(ips_noroute);
 683                 error = EHOSTUNREACH;
 684                 goto bad;
 685         }
 686         /* Update variables that are affected by ipsec4_output(). */
 687         ip = mtod(m, struct ip *);
 688         hlen = ip->ip_hl << 2;
 689 #endif /* IPSEC */
 690
 691         /* Jump over all PFIL processing if hooks are not active. */
 692         if (PFIL_HOOKED_OUT(V_inet_pfil_head)) {
 693                 switch (ip_output_pfil(&m, ifp, flags, inp, dst, &fibnum,
 694                     &error)) {
 695                 case 1: /* Finished */
 696                         goto done;
 697
 698                 case 0: /* Continue normally */
 699                         ip = mtod(m, struct ip *);
 700                         break;
 701
 702                 case -1: /* Need to try again */
 703                         /* Reset everything for a new round */
 704                         if (ro != NULL) {
 705                                 RO_RTFREE(ro);
 706                                 ro->ro_prepend = NULL;
 707                         }
 708                         gw = dst;
 709                         ip = mtod(m, struct ip *);
 710                         goto again;
 711
 712                 }
 713         }
 714
 715         /* IN_LOOPBACK must not appear on the wire - RFC1122. */
 716         if (IN_LOOPBACK(ntohl(ip->ip_dst.s_addr)) ||
 717             IN_LOOPBACK(ntohl(ip->ip_src.s_addr))) {
 718                 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
 719                         IPSTAT_INC(ips_badaddr);
 720                         error = EADDRNOTAVAIL;
 721                         goto bad;
 722                 }
 723         }
 724
 725         m->m_pkthdr.csum_flags |= CSUM_IP;
 726         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
 727                 m = mb_unmapped_to_ext(m);
 728                 if (m == NULL) {
 729                         IPSTAT_INC(ips_odropped);
 730                         error = ENOBUFS;
 731                         goto bad;
 732                 }
 733                 in_delayed_cksum(m);
 734                 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
 735         } else if ((ifp->if_capenable & IFCAP_NOMAP) == 0) {
 736                 m = mb_unmapped_to_ext(m);
 737                 if (m == NULL) {
 738                         IPSTAT_INC(ips_odropped);
 739                         error = ENOBUFS;
 740                         goto bad;
 741                 }
 742         }
 743 #ifdef SCTP
 744         if (m->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
 745                 m = mb_unmapped_to_ext(m);
 746                 if (m == NULL) {
 747                         IPSTAT_INC(ips_odropped);
 748                         error = ENOBUFS;
 749                         goto bad;
 750                 }
 751                 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
 752                 m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
 753         }
 754 #endif
 755
 756         /*
 757          * If small enough for interface, or the interface will take
 758          * care of the fragmentation for us, we can just send directly.
 759          */
 760         if (ip_len <= mtu ||
 761             (m->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0) {
 762                 ip->ip_sum = 0;
 763                 if (m->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
 764                         ip->ip_sum = in_cksum(m, hlen);
 765                         m->m_pkthdr.csum_flags &= ~CSUM_IP;
 766                 }
 767
 768                 /*
 769                  * Record statistics for this interface address.
 770                  * With CSUM_TSO the byte/packet count will be slightly
 771                  * incorrect because we count the IP+TCP headers only
 772                  * once instead of for every generated packet.
 773                  */
 774                 if (!(flags & IP_FORWARDING) && ia) {
 775                         if (m->m_pkthdr.csum_flags & CSUM_TSO)
 776                                 counter_u64_add(ia->ia_ifa.ifa_opackets,
 777                                     m->m_pkthdr.len / m->m_pkthdr.tso_segsz);
 778                         else
 779                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
 780
 781                         counter_u64_add(ia->ia_ifa.ifa_obytes, m->m_pkthdr.len);
 782                 }
 783 #ifdef MBUF_STRESS_TEST
 784                 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size)
 785                         m = m_fragment(m, M_NOWAIT, mbuf_frag_size);
 786 #endif
 787                 /*
 788                  * Reset layer specific mbuf flags
 789                  * to avoid confusing lower layers.
 790                  */
 791                 m_clrprotoflags(m);
 792                 IP_PROBE(send, NULL, NULL, ip, ifp, ip, NULL);
 793                 error = ip_output_send(inp, ifp, m, gw, ro,
 794                     (flags & IP_NO_SND_TAG_RL) ? false : true);
 795                 goto done;
 796         }
 797
 798         /* Balk when DF bit is set or the interface didn't support TSO. */
 799         if ((ip_off & IP_DF) || (m->m_pkthdr.csum_flags & CSUM_TSO)) {
 800                 error = EMSGSIZE;
 801                 IPSTAT_INC(ips_cantfrag);
 802                 goto bad;
 803         }
 804
 805         /*
 806          * Too large for interface; fragment if possible. If successful,
 807          * on return, m will point to a list of packets to be sent.
 808          */
 809         error = ip_fragment(ip, &m, mtu, ifp->if_hwassist);
 810         if (error)
 811                 goto bad;
 812         for (; m; m = m0) {
 813                 m0 = m->m_nextpkt;
 814                 m->m_nextpkt = 0;
 815                 if (error == 0) {
 816                         /* Record statistics for this interface address. */
 817                         if (ia != NULL) {
 818                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
 819                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
 820                                     m->m_pkthdr.len);
 821                         }
 822                         /*
 823                          * Reset layer specific mbuf flags
 824                          * to avoid confusing upper layers.
 825                          */
 826                         m_clrprotoflags(m);
 827
 828                         IP_PROBE(send, NULL, NULL, mtod(m, struct ip *), ifp,
 829                             mtod(m, struct ip *), NULL);
 830                         error = ip_output_send(inp, ifp, m, gw, ro, true);
 831                 } else
 832                         m_freem(m);
 833         }
 834
 835         if (error == 0)
 836                 IPSTAT_INC(ips_fragmented);
 837
 838 done:
 839         return (error);
 840  bad:
 841         m_freem(m);
 842         goto done;
 843 }
 844
 845 /*
 846  * Create a chain of fragments which fit the given mtu. m_frag points to the
 847  * mbuf to be fragmented; on return it points to the chain with the fragments.
 848  * Return 0 if no error. If error, m_frag may contain a partially built
 849  * chain of fragments that should be freed by the caller.
 850  *
 851  * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
 852  */
 853 int
 854 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
 855     u_long if_hwassist_flags)
 856 {
 857         int error = 0;
 858         int hlen = ip->ip_hl << 2;
 859         int len = (mtu - hlen) & ~7;    /* size of payload in each fragment */
 860         int off;
 861         struct mbuf *m0 = *m_frag;      /* the original packet          */
 862         int firstlen;
 863         struct mbuf **mnext;
 864         int nfrags;
 865         uint16_t ip_len, ip_off;
 866
 867         ip_len = ntohs(ip->ip_len);
 868         ip_off = ntohs(ip->ip_off);
 869
 870         if (ip_off & IP_DF) {   /* Fragmentation not allowed */
 871                 IPSTAT_INC(ips_cantfrag);
 872                 return EMSGSIZE;
 873         }
 874
 875         /*
 876          * Must be able to put at least 8 bytes per fragment.
 877          */
 878         if (len < 8)
 879                 return EMSGSIZE;
 880
 881         /*
 882          * If the interface will not calculate checksums on
 883          * fragmented packets, then do it here.
 884          */
 885         if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 886                 m0 = mb_unmapped_to_ext(m0);
 887                 if (m0 == NULL) {
 888                         error = ENOBUFS;
 889                         IPSTAT_INC(ips_odropped);
 890                         goto done;
 891                 }
 892                 in_delayed_cksum(m0);
 893                 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
 894         }
 895 #ifdef SCTP
 896         if (m0->m_pkthdr.csum_flags & CSUM_SCTP) {
 897                 m0 = mb_unmapped_to_ext(m0);
 898                 if (m0 == NULL) {
 899                         error = ENOBUFS;
 900                         IPSTAT_INC(ips_odropped);
 901                         goto done;
 902                 }
 903                 sctp_delayed_cksum(m0, hlen);
 904                 m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
 905         }
 906 #endif
 907         if (len > PAGE_SIZE) {
 908                 /*
 909                  * Fragment large datagrams such that each segment
 910                  * contains a multiple of PAGE_SIZE amount of data,
 911                  * plus headers. This enables a receiver to perform
 912                  * page-flipping zero-copy optimizations.
 913                  *
 914                  * XXX When does this help given that sender and receiver
 915                  * could have different page sizes, and also mtu could
 916                  * be less than the receiver's page size ?
 917                  */
 918                 int newlen;
 919
 920                 off = MIN(mtu, m0->m_pkthdr.len);
 921
 922                 /*
 923                  * firstlen (off - hlen) must be aligned on an
 924                  * 8-byte boundary
 925                  */
 926                 if (off < hlen)
 927                         goto smart_frag_failure;
 928                 off = ((off - hlen) & ~7) + hlen;
 929                 newlen = (~PAGE_MASK) & mtu;
 930                 if ((newlen + sizeof (struct ip)) > mtu) {
 931                         /* we failed, go back the default */
 932 smart_frag_failure:
 933                         newlen = len;
 934                         off = hlen + len;
 935                 }
 936                 len = newlen;
 937
 938         } else {
 939                 off = hlen + len;
 940         }
 941
 942         firstlen = off - hlen;
 943         mnext = &m0->m_nextpkt;         /* pointer to next packet */
 944
 945         /*
 946          * Loop through length of segment after first fragment,
 947          * make new header and copy data of each part and link onto chain.
 948          * Here, m0 is the original packet, m is the fragment being created.
 949          * The fragments are linked off the m_nextpkt of the original
 950          * packet, which after processing serves as the first fragment.
 951          */
 952         for (nfrags = 1; off < ip_len; off += len, nfrags++) {
 953                 struct ip *mhip;        /* ip header on the fragment */
 954                 struct mbuf *m;
 955                 int mhlen = sizeof (struct ip);
 956
 957                 m = m_gethdr(M_NOWAIT, MT_DATA);
 958                 if (m == NULL) {
 959                         error = ENOBUFS;
 960                         IPSTAT_INC(ips_odropped);
 961                         goto done;
 962                 }
 963                 /*
 964                  * Make sure the complete packet header gets copied
 965                  * from the originating mbuf to the newly created
 966                  * mbuf. This also ensures that existing firewall
 967                  * classification(s), VLAN tags and so on get copied
 968                  * to the resulting fragmented packet(s):
 969                  */
 970                 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
 971                         m_free(m);
 972                         error = ENOBUFS;
 973                         IPSTAT_INC(ips_odropped);
 974                         goto done;
 975                 }
 976                 /*
 977                  * In the first mbuf, leave room for the link header, then
 978                  * copy the original IP header including options. The payload
 979                  * goes into an additional mbuf chain returned by m_copym().
 980                  */
 981                 m->m_data += max_linkhdr;
 982                 mhip = mtod(m, struct ip *);
 983                 *mhip = *ip;
 984                 if (hlen > sizeof (struct ip)) {
 985                         mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
 986                         mhip->ip_v = IPVERSION;
 987                         mhip->ip_hl = mhlen >> 2;
 988                 }
 989                 m->m_len = mhlen;
 990                 /* XXX do we need to add ip_off below ? */
 991                 mhip->ip_off = ((off - hlen) >> 3) + ip_off;
 992                 if (off + len >= ip_len)
 993                         len = ip_len - off;
 994                 else
 995                         mhip->ip_off |= IP_MF;
 996                 mhip->ip_len = htons((u_short)(len + mhlen));
 997                 m->m_next = m_copym(m0, off, len, M_NOWAIT);
 998                 if (m->m_next == NULL) {        /* copy failed */
 999                         m_free(m);
1000                         error = ENOBUFS;        /* ??? */
1001                         IPSTAT_INC(ips_odropped);
1002                         goto done;
1003                 }
1004                 m->m_pkthdr.len = mhlen + len;
1005 #ifdef MAC
1006                 mac_netinet_fragment(m0, m);
1007 #endif
1008                 mhip->ip_off = htons(mhip->ip_off);
1009                 mhip->ip_sum = 0;
1010                 if (m->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
1011                         mhip->ip_sum = in_cksum(m, mhlen);
1012                         m->m_pkthdr.csum_flags &= ~CSUM_IP;
1013                 }
1014                 *mnext = m;
1015                 mnext = &m->m_nextpkt;
1016         }
1017         IPSTAT_ADD(ips_ofragments, nfrags);
1018
1019         /*
1020          * Update first fragment by trimming what's been copied out
1021          * and updating header.
1022          */
1023         m_adj(m0, hlen + firstlen - ip_len);
1024         m0->m_pkthdr.len = hlen + firstlen;
1025         ip->ip_len = htons((u_short)m0->m_pkthdr.len);
1026         ip->ip_off = htons(ip_off | IP_MF);
1027         ip->ip_sum = 0;
1028         if (m0->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
1029                 ip->ip_sum = in_cksum(m0, hlen);
1030                 m0->m_pkthdr.csum_flags &= ~CSUM_IP;
1031         }
1032
1033 done:
1034         *m_frag = m0;
1035         return error;
1036 }
1037
1038 void
1039 in_delayed_cksum(struct mbuf *m)
1040 {
1041         struct ip *ip;
1042         struct udphdr *uh;
1043         uint16_t cklen, csum, offset;
1044
1045         ip = mtod(m, struct ip *);
1046         offset = ip->ip_hl << 2 ;
1047
1048         if (m->m_pkthdr.csum_flags & CSUM_UDP) {
1049                 /* if udp header is not in the first mbuf copy udplen */
1050                 if (offset + sizeof(struct udphdr) > m->m_len) {
1051                         m_copydata(m, offset + offsetof(struct udphdr,
1052                             uh_ulen), sizeof(cklen), (caddr_t)&cklen);
1053                         cklen = ntohs(cklen);
1054                 } else {
1055                         uh = (struct udphdr *)mtodo(m, offset);
1056                         cklen = ntohs(uh->uh_ulen);
1057                 }
1058                 csum = in_cksum_skip(m, cklen + offset, offset);
1059                 if (csum == 0)
1060                         csum = 0xffff;
1061         } else {
1062                 cklen = ntohs(ip->ip_len);
1063                 csum = in_cksum_skip(m, cklen, offset);
1064         }
1065         offset += m->m_pkthdr.csum_data;        /* checksum offset */
1066
1067         if (offset + sizeof(csum) > m->m_len)
1068                 m_copyback(m, offset, sizeof(csum), (caddr_t)&csum);
1069         else
1070                 *(u_short *)mtodo(m, offset) = csum;
1071 }
1072
1073 /*
1074  * IP socket option processing.
1075  */
1076 int
1077 ip_ctloutput(struct socket *so, struct sockopt *sopt)
1078 {
1079         struct inpcb *inp = sotoinpcb(so);
1080         int     error, optval;
1081 #ifdef  RSS
1082         uint32_t rss_bucket;
1083         int retval;
1084 #endif
1085
1086         error = optval = 0;
1087         if (sopt->sopt_level != IPPROTO_IP) {
1088                 error = EINVAL;
1089
1090                 if (sopt->sopt_level == SOL_SOCKET &&
1091                     sopt->sopt_dir == SOPT_SET) {
1092                         switch (sopt->sopt_name) {
1093                         case SO_REUSEADDR:
1094                                 INP_WLOCK(inp);
1095                                 if ((so->so_options & SO_REUSEADDR) != 0)
1096                                         inp->inp_flags2 |= INP_REUSEADDR;
1097                                 else
1098                                         inp->inp_flags2 &= ~INP_REUSEADDR;
1099                                 INP_WUNLOCK(inp);
1100                                 error = 0;
1101                                 break;
1102                         case SO_REUSEPORT:
1103                                 INP_WLOCK(inp);
1104                                 if ((so->so_options & SO_REUSEPORT) != 0)
1105                                         inp->inp_flags2 |= INP_REUSEPORT;
1106                                 else
1107                                         inp->inp_flags2 &= ~INP_REUSEPORT;
1108                                 INP_WUNLOCK(inp);
1109                                 error = 0;
1110                                 break;
1111                         case SO_REUSEPORT_LB:
1112                                 INP_WLOCK(inp);
1113                                 if ((so->so_options & SO_REUSEPORT_LB) != 0)
1114                                         inp->inp_flags2 |= INP_REUSEPORT_LB;
1115                                 else
1116                                         inp->inp_flags2 &= ~INP_REUSEPORT_LB;
1117                                 INP_WUNLOCK(inp);
1118                                 error = 0;
1119                                 break;
1120                         case SO_SETFIB:
1121                                 INP_WLOCK(inp);
1122                                 inp->inp_inc.inc_fibnum = so->so_fibnum;
1123                                 INP_WUNLOCK(inp);
1124                                 error = 0;
1125                                 break;
1126                         case SO_MAX_PACING_RATE:
1127 #ifdef RATELIMIT
1128                                 INP_WLOCK(inp);
1129                                 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1130                                 INP_WUNLOCK(inp);
1131                                 error = 0;
1132 #else
1133                                 error = EOPNOTSUPP;
1134 #endif
1135                                 break;
1136                         default:
1137                                 break;
1138                         }
1139                 }
1140                 return (error);
1141         }
1142
1143         switch (sopt->sopt_dir) {
1144         case SOPT_SET:
1145                 switch (sopt->sopt_name) {
1146                 case IP_OPTIONS:
1147 #ifdef notyet
1148                 case IP_RETOPTS:
1149 #endif
1150                 {
1151                         struct mbuf *m;
1152                         if (sopt->sopt_valsize > MLEN) {
1153                                 error = EMSGSIZE;
1154                                 break;
1155                         }
1156                         m = m_get(sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
1157                         if (m == NULL) {
1158                                 error = ENOBUFS;
1159                                 break;
1160                         }
1161                         m->m_len = sopt->sopt_valsize;
1162                         error = sooptcopyin(sopt, mtod(m, char *), m->m_len,
1163                                             m->m_len);
1164                         if (error) {
1165                                 m_free(m);
1166                                 break;
1167                         }
1168                         INP_WLOCK(inp);
1169                         error = ip_pcbopts(inp, sopt->sopt_name, m);
1170                         INP_WUNLOCK(inp);
1171                         return (error);
1172                 }
1173
1174                 case IP_BINDANY:
1175                         if (sopt->sopt_td != NULL) {
1176                                 error = priv_check(sopt->sopt_td,
1177                                     PRIV_NETINET_BINDANY);
1178                                 if (error)
1179                                         break;
1180                         }
1181                         /* FALLTHROUGH */
1182                 case IP_BINDMULTI:
1183 #ifdef  RSS
1184                 case IP_RSS_LISTEN_BUCKET:
1185 #endif
1186                 case IP_TOS:
1187                 case IP_TTL:
1188                 case IP_MINTTL:
1189                 case IP_RECVOPTS:
1190                 case IP_RECVRETOPTS:
1191                 case IP_ORIGDSTADDR:
1192                 case IP_RECVDSTADDR:
1193                 case IP_RECVTTL:
1194                 case IP_RECVIF:
1195                 case IP_ONESBCAST:
1196                 case IP_DONTFRAG:
1197                 case IP_RECVTOS:
1198                 case IP_RECVFLOWID:
1199 #ifdef  RSS
1200                 case IP_RECVRSSBUCKETID:
1201 #endif
1202                         error = sooptcopyin(sopt, &optval, sizeof optval,
1203                                             sizeof optval);
1204                         if (error)
1205                                 break;
1206
1207                         switch (sopt->sopt_name) {
1208                         case IP_TOS:
1209                                 inp->inp_ip_tos = optval;
1210                                 break;
1211
1212                         case IP_TTL:
1213                                 inp->inp_ip_ttl = optval;
1214                                 break;
1215
1216                         case IP_MINTTL:
1217                                 if (optval >= 0 && optval <= MAXTTL)
1218                                         inp->inp_ip_minttl = optval;
1219                                 else
1220                                         error = EINVAL;
1221                                 break;
1222
1223 #define OPTSET(bit) do {                                                \
1224         INP_WLOCK(inp);                                                 \
1225         if (optval)                                                     \
1226                 inp->inp_flags |= bit;                                  \
1227         else                                                            \
1228                 inp->inp_flags &= ~bit;                                 \
1229         INP_WUNLOCK(inp);                                               \
1230 } while (0)
1231
1232 #define OPTSET2(bit, val) do {                                          \
1233         INP_WLOCK(inp);                                                 \
1234         if (val)                                                        \
1235                 inp->inp_flags2 |= bit;                                 \
1236         else                                                            \
1237                 inp->inp_flags2 &= ~bit;                                \
1238         INP_WUNLOCK(inp);                                               \
1239 } while (0)
1240
1241                         case IP_RECVOPTS:
1242                                 OPTSET(INP_RECVOPTS);
1243                                 break;
1244
1245                         case IP_RECVRETOPTS:
1246                                 OPTSET(INP_RECVRETOPTS);
1247                                 break;
1248
1249                         case IP_RECVDSTADDR:
1250                                 OPTSET(INP_RECVDSTADDR);
1251                                 break;
1252
1253                         case IP_ORIGDSTADDR:
1254                                 OPTSET2(INP_ORIGDSTADDR, optval);
1255                                 break;
1256
1257                         case IP_RECVTTL:
1258                                 OPTSET(INP_RECVTTL);
1259                                 break;
1260
1261                         case IP_RECVIF:
1262                                 OPTSET(INP_RECVIF);
1263                                 break;
1264
1265                         case IP_ONESBCAST:
1266                                 OPTSET(INP_ONESBCAST);
1267                                 break;
1268                         case IP_DONTFRAG:
1269                                 OPTSET(INP_DONTFRAG);
1270                                 break;
1271                         case IP_BINDANY:
1272                                 OPTSET(INP_BINDANY);
1273                                 break;
1274                         case IP_RECVTOS:
1275                                 OPTSET(INP_RECVTOS);
1276                                 break;
1277                         case IP_BINDMULTI:
1278                                 OPTSET2(INP_BINDMULTI, optval);
1279                                 break;
1280                         case IP_RECVFLOWID:
1281                                 OPTSET2(INP_RECVFLOWID, optval);
1282                                 break;
1283 #ifdef  RSS
1284                         case IP_RSS_LISTEN_BUCKET:
1285                                 if ((optval >= 0) &&
1286                                     (optval < rss_getnumbuckets())) {
1287                                         inp->inp_rss_listen_bucket = optval;
1288                                         OPTSET2(INP_RSS_BUCKET_SET, 1);
1289                                 } else {
1290                                         error = EINVAL;
1291                                 }
1292                                 break;
1293                         case IP_RECVRSSBUCKETID:
1294                                 OPTSET2(INP_RECVRSSBUCKETID, optval);
1295                                 break;
1296 #endif
1297                         }
1298                         break;
1299 #undef OPTSET
1300 #undef OPTSET2
1301
1302                 /*
1303                  * Multicast socket options are processed by the in_mcast
1304                  * module.
1305                  */
1306                 case IP_MULTICAST_IF:
1307                 case IP_MULTICAST_VIF:
1308                 case IP_MULTICAST_TTL:
1309                 case IP_MULTICAST_LOOP:
1310                 case IP_ADD_MEMBERSHIP:
1311                 case IP_DROP_MEMBERSHIP:
1312                 case IP_ADD_SOURCE_MEMBERSHIP:
1313                 case IP_DROP_SOURCE_MEMBERSHIP:
1314                 case IP_BLOCK_SOURCE:
1315                 case IP_UNBLOCK_SOURCE:
1316                 case IP_MSFILTER:
1317                 case MCAST_JOIN_GROUP:
1318                 case MCAST_LEAVE_GROUP:
1319                 case MCAST_JOIN_SOURCE_GROUP:
1320                 case MCAST_LEAVE_SOURCE_GROUP:
1321                 case MCAST_BLOCK_SOURCE:
1322                 case MCAST_UNBLOCK_SOURCE:
1323                         error = inp_setmoptions(inp, sopt);
1324                         break;
1325
1326                 case IP_PORTRANGE:
1327                         error = sooptcopyin(sopt, &optval, sizeof optval,
1328                                             sizeof optval);
1329                         if (error)
1330                                 break;
1331
1332                         INP_WLOCK(inp);
1333                         switch (optval) {
1334                         case IP_PORTRANGE_DEFAULT:
1335                                 inp->inp_flags &= ~(INP_LOWPORT);
1336                                 inp->inp_flags &= ~(INP_HIGHPORT);
1337                                 break;
1338
1339                         case IP_PORTRANGE_HIGH:
1340                                 inp->inp_flags &= ~(INP_LOWPORT);
1341                                 inp->inp_flags |= INP_HIGHPORT;
1342                                 break;
1343
1344                         case IP_PORTRANGE_LOW:
1345                                 inp->inp_flags &= ~(INP_HIGHPORT);
1346                                 inp->inp_flags |= INP_LOWPORT;
1347                                 break;
1348
1349                         default:
1350                                 error = EINVAL;
1351                                 break;
1352                         }
1353                         INP_WUNLOCK(inp);
1354                         break;
1355
1356 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1357                 case IP_IPSEC_POLICY:
1358                         if (IPSEC_ENABLED(ipv4)) {
1359                                 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1360                                 break;
1361                         }
1362                         /* FALLTHROUGH */
1363 #endif /* IPSEC */
1364
1365                 default:
1366                         error = ENOPROTOOPT;
1367                         break;
1368                 }
1369                 break;
1370
1371         case SOPT_GET:
1372                 switch (sopt->sopt_name) {
1373                 case IP_OPTIONS:
1374                 case IP_RETOPTS:
1375                         INP_RLOCK(inp);
1376                         if (inp->inp_options) {
1377                                 struct mbuf *options;
1378
1379                                 options = m_copym(inp->inp_options, 0,
1380                                     M_COPYALL, M_NOWAIT);
1381                                 INP_RUNLOCK(inp);
1382                                 if (options != NULL) {
1383                                         error = sooptcopyout(sopt,
1384                                                              mtod(options, char *),
1385                                                              options->m_len);
1386                                         m_freem(options);
1387                                 } else
1388                                         error = ENOMEM;
1389                         } else {
1390                                 INP_RUNLOCK(inp);
1391                                 sopt->sopt_valsize = 0;
1392                         }
1393                         break;
1394
1395                 case IP_TOS:
1396                 case IP_TTL:
1397                 case IP_MINTTL:
1398                 case IP_RECVOPTS:
1399                 case IP_RECVRETOPTS:
1400                 case IP_ORIGDSTADDR:
1401                 case IP_RECVDSTADDR:
1402                 case IP_RECVTTL:
1403                 case IP_RECVIF:
1404                 case IP_PORTRANGE:
1405                 case IP_ONESBCAST:
1406                 case IP_DONTFRAG:
1407                 case IP_BINDANY:
1408                 case IP_RECVTOS:
1409                 case IP_BINDMULTI:
1410                 case IP_FLOWID:
1411                 case IP_FLOWTYPE:
1412                 case IP_RECVFLOWID:
1413 #ifdef  RSS
1414                 case IP_RSSBUCKETID:
1415                 case IP_RECVRSSBUCKETID:
1416 #endif
1417                         switch (sopt->sopt_name) {
1418
1419                         case IP_TOS:
1420                                 optval = inp->inp_ip_tos;
1421                                 break;
1422
1423                         case IP_TTL:
1424                                 optval = inp->inp_ip_ttl;
1425                                 break;
1426
1427                         case IP_MINTTL:
1428                                 optval = inp->inp_ip_minttl;
1429                                 break;
1430
1431 #define OPTBIT(bit)     (inp->inp_flags & bit ? 1 : 0)
1432 #define OPTBIT2(bit)    (inp->inp_flags2 & bit ? 1 : 0)
1433
1434                         case IP_RECVOPTS:
1435                                 optval = OPTBIT(INP_RECVOPTS);
1436                                 break;
1437
1438                         case IP_RECVRETOPTS:
1439                                 optval = OPTBIT(INP_RECVRETOPTS);
1440                                 break;
1441
1442                         case IP_RECVDSTADDR:
1443                                 optval = OPTBIT(INP_RECVDSTADDR);
1444                                 break;
1445
1446                         case IP_ORIGDSTADDR:
1447                                 optval = OPTBIT2(INP_ORIGDSTADDR);
1448                                 break;
1449
1450                         case IP_RECVTTL:
1451                                 optval = OPTBIT(INP_RECVTTL);
1452                                 break;
1453
1454                         case IP_RECVIF:
1455                                 optval = OPTBIT(INP_RECVIF);
1456                                 break;
1457
1458                         case IP_PORTRANGE:
1459                                 if (inp->inp_flags & INP_HIGHPORT)
1460                                         optval = IP_PORTRANGE_HIGH;
1461                                 else if (inp->inp_flags & INP_LOWPORT)
1462                                         optval = IP_PORTRANGE_LOW;
1463                                 else
1464                                         optval = 0;
1465                                 break;
1466
1467                         case IP_ONESBCAST:
1468                                 optval = OPTBIT(INP_ONESBCAST);
1469                                 break;
1470                         case IP_DONTFRAG:
1471                                 optval = OPTBIT(INP_DONTFRAG);
1472                                 break;
1473                         case IP_BINDANY:
1474                                 optval = OPTBIT(INP_BINDANY);
1475                                 break;
1476                         case IP_RECVTOS:
1477                                 optval = OPTBIT(INP_RECVTOS);
1478                                 break;
1479                         case IP_FLOWID:
1480                                 optval = inp->inp_flowid;
1481                                 break;
1482                         case IP_FLOWTYPE:
1483                                 optval = inp->inp_flowtype;
1484                                 break;
1485                         case IP_RECVFLOWID:
1486                                 optval = OPTBIT2(INP_RECVFLOWID);
1487                                 break;
1488 #ifdef  RSS
1489                         case IP_RSSBUCKETID:
1490                                 retval = rss_hash2bucket(inp->inp_flowid,
1491                                     inp->inp_flowtype,
1492                                     &rss_bucket);
1493                                 if (retval == 0)
1494                                         optval = rss_bucket;
1495                                 else
1496                                         error = EINVAL;
1497                                 break;
1498                         case IP_RECVRSSBUCKETID:
1499                                 optval = OPTBIT2(INP_RECVRSSBUCKETID);
1500                                 break;
1501 #endif
1502                         case IP_BINDMULTI:
1503                                 optval = OPTBIT2(INP_BINDMULTI);
1504                                 break;
1505                         }
1506                         error = sooptcopyout(sopt, &optval, sizeof optval);
1507                         break;
1508
1509                 /*
1510                  * Multicast socket options are processed by the in_mcast
1511                  * module.
1512                  */
1513                 case IP_MULTICAST_IF:
1514                 case IP_MULTICAST_VIF:
1515                 case IP_MULTICAST_TTL:
1516                 case IP_MULTICAST_LOOP:
1517                 case IP_MSFILTER:
1518                         error = inp_getmoptions(inp, sopt);
1519                         break;
1520
1521 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1522                 case IP_IPSEC_POLICY:
1523                         if (IPSEC_ENABLED(ipv4)) {
1524                                 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1525                                 break;
1526                         }
1527                         /* FALLTHROUGH */
1528 #endif /* IPSEC */
1529
1530                 default:
1531                         error = ENOPROTOOPT;
1532                         break;
1533                 }
1534                 break;
1535         }
1536         return (error);
1537 }
1538
1539 /*
1540  * Routine called from ip_output() to loop back a copy of an IP multicast
1541  * packet to the input queue of a specified interface.  Note that this
1542  * calls the output routine of the loopback "driver", but with an interface
1543  * pointer that might NOT be a loopback interface -- evil, but easier than
1544  * replicating that code here.
1545  */
1546 static void
1547 ip_mloopback(struct ifnet *ifp, const struct mbuf *m, int hlen)
1548 {
1549         struct ip *ip;
1550         struct mbuf *copym;
1551
1552         /*
1553          * Make a deep copy of the packet because we're going to
1554          * modify the pack in order to generate checksums.
1555          */
1556         copym = m_dup(m, M_NOWAIT);
1557         if (copym != NULL && (!M_WRITABLE(copym) || copym->m_len < hlen))
1558                 copym = m_pullup(copym, hlen);
1559         if (copym != NULL) {
1560                 /* If needed, compute the checksum and mark it as valid. */
1561                 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
1562                         in_delayed_cksum(copym);
1563                         copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1564                         copym->m_pkthdr.csum_flags |=
1565                             CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1566                         copym->m_pkthdr.csum_data = 0xffff;
1567                 }
1568                 /*
1569                  * We don't bother to fragment if the IP length is greater
1570                  * than the interface's MTU.  Can this possibly matter?
1571                  */
1572                 ip = mtod(copym, struct ip *);
1573                 ip->ip_sum = 0;
1574                 ip->ip_sum = in_cksum(copym, hlen);
1575                 if_simloop(ifp, copym, AF_INET, 0);
1576         }
1577 }