sys/netinet/ip_output.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1982, 1986, 1988, 1990, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      @(#)ip_output.c 8.3 (Berkeley) 1/21/94
  32  */
  33
  34 #include <sys/cdefs.h>
  35 __FBSDID("$FreeBSD$");
  36
  37 #include "opt_inet.h"
  38 #include "opt_ratelimit.h"
  39 #include "opt_ipsec.h"
  40 #include "opt_mbuf_stress_test.h"
  41 #include "opt_mpath.h"
  42 #include "opt_route.h"
  43 #include "opt_sctp.h"
  44 #include "opt_rss.h"
  45
  46 #include <sys/param.h>
  47 #include <sys/systm.h>
  48 #include <sys/kernel.h>
  49 #include <sys/lock.h>
  50 #include <sys/malloc.h>
  51 #include <sys/mbuf.h>
  52 #include <sys/priv.h>
  53 #include <sys/proc.h>
  54 #include <sys/protosw.h>
  55 #include <sys/rmlock.h>
  56 #include <sys/sdt.h>
  57 #include <sys/socket.h>
  58 #include <sys/socketvar.h>
  59 #include <sys/sysctl.h>
  60 #include <sys/ucred.h>
  61
  62 #include <net/if.h>
  63 #include <net/if_var.h>
  64 #include <net/if_llatbl.h>
  65 #include <net/netisr.h>
  66 #include <net/pfil.h>
  67 #include <net/route.h>
  68 #ifdef RADIX_MPATH
  69 #include <net/radix_mpath.h>
  70 #endif
  71 #include <net/rss_config.h>
  72 #include <net/vnet.h>
  73
  74 #include <netinet/in.h>
  75 #include <netinet/in_fib.h>
  76 #include <netinet/in_kdtrace.h>
  77 #include <netinet/in_systm.h>
  78 #include <netinet/ip.h>
  79 #include <netinet/in_pcb.h>
  80 #include <netinet/in_rss.h>
  81 #include <netinet/in_var.h>
  82 #include <netinet/ip_var.h>
  83 #include <netinet/ip_options.h>
  84
  85 #include <netinet/udp.h>
  86 #include <netinet/udp_var.h>
  87
  88 #ifdef SCTP
  89 #include <netinet/sctp.h>
  90 #include <netinet/sctp_crc32.h>
  91 #endif
  92
  93 #include <netipsec/ipsec_support.h>
  94
  95 #include <machine/in_cksum.h>
  96
  97 #include <security/mac/mac_framework.h>
  98
  99 #ifdef MBUF_STRESS_TEST
 100 static int mbuf_frag_size = 0;
 101 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
 102         &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
 103 #endif
 104
 105 static void     ip_mloopback(struct ifnet *, const struct mbuf *, int);
 106
 107
 108 extern int in_mcast_loop;
 109 extern  struct protosw inetsw[];
 110
 111 static inline int
 112 ip_output_pfil(struct mbuf **mp, struct ifnet *ifp, struct inpcb *inp,
 113     struct sockaddr_in *dst, int *fibnum, int *error)
 114 {
 115         struct m_tag *fwd_tag = NULL;
 116         struct mbuf *m;
 117         struct in_addr odst;
 118         struct ip *ip;
 119
 120         m = *mp;
 121         ip = mtod(m, struct ip *);
 122
 123         /* Run through list of hooks for output packets. */
 124         odst.s_addr = ip->ip_dst.s_addr;
 125         switch (pfil_run_hooks(V_inet_pfil_head, mp, ifp, PFIL_OUT, inp)) {
 126         case PFIL_DROPPED:
 127                 *error = EPERM;
 128                 /* FALLTHROUGH */
 129         case PFIL_CONSUMED:
 130                 return 1; /* Finished */
 131         case PFIL_PASS:
 132                 *error = 0;
 133         }
 134         m = *mp;
 135         ip = mtod(m, struct ip *);
 136
 137         /* See if destination IP address was changed by packet filter. */
 138         if (odst.s_addr != ip->ip_dst.s_addr) {
 139                 m->m_flags |= M_SKIP_FIREWALL;
 140                 /* If destination is now ourself drop to ip_input(). */
 141                 if (in_localip(ip->ip_dst)) {
 142                         m->m_flags |= M_FASTFWD_OURS;
 143                         if (m->m_pkthdr.rcvif == NULL)
 144                                 m->m_pkthdr.rcvif = V_loif;
 145                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 146                                 m->m_pkthdr.csum_flags |=
 147                                         CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
 148                                 m->m_pkthdr.csum_data = 0xffff;
 149                         }
 150                         m->m_pkthdr.csum_flags |=
 151                                 CSUM_IP_CHECKED | CSUM_IP_VALID;
 152 #ifdef SCTP
 153                         if (m->m_pkthdr.csum_flags & CSUM_SCTP)
 154                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 155 #endif
 156                         *error = netisr_queue(NETISR_IP, m);
 157                         return 1; /* Finished */
 158                 }
 159
 160                 bzero(dst, sizeof(*dst));
 161                 dst->sin_family = AF_INET;
 162                 dst->sin_len = sizeof(*dst);
 163                 dst->sin_addr = ip->ip_dst;
 164
 165                 return -1; /* Reloop */
 166         }
 167         /* See if fib was changed by packet filter. */
 168         if ((*fibnum) != M_GETFIB(m)) {
 169                 m->m_flags |= M_SKIP_FIREWALL;
 170                 *fibnum = M_GETFIB(m);
 171                 return -1; /* Reloop for FIB change */
 172         }
 173
 174         /* See if local, if yes, send it to netisr with IP_FASTFWD_OURS. */
 175         if (m->m_flags & M_FASTFWD_OURS) {
 176                 if (m->m_pkthdr.rcvif == NULL)
 177                         m->m_pkthdr.rcvif = V_loif;
 178                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 179                         m->m_pkthdr.csum_flags |=
 180                                 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
 181                         m->m_pkthdr.csum_data = 0xffff;
 182                 }
 183 #ifdef SCTP
 184                 if (m->m_pkthdr.csum_flags & CSUM_SCTP)
 185                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 186 #endif
 187                 m->m_pkthdr.csum_flags |=
 188                         CSUM_IP_CHECKED | CSUM_IP_VALID;
 189
 190                 *error = netisr_queue(NETISR_IP, m);
 191                 return 1; /* Finished */
 192         }
 193         /* Or forward to some other address? */
 194         if ((m->m_flags & M_IP_NEXTHOP) &&
 195             ((fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL)) {
 196                 bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in));
 197                 m->m_flags |= M_SKIP_FIREWALL;
 198                 m->m_flags &= ~M_IP_NEXTHOP;
 199                 m_tag_delete(m, fwd_tag);
 200
 201                 return -1; /* Reloop for CHANGE of dst */
 202         }
 203
 204         return 0;
 205 }
 206
 207 /*
 208  * IP output.  The packet in mbuf chain m contains a skeletal IP
 209  * header (with len, off, ttl, proto, tos, src, dst).
 210  * The mbuf chain containing the packet will be freed.
 211  * The mbuf opt, if present, will not be freed.
 212  * If route ro is present and has ro_rt initialized, route lookup would be
 213  * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
 214  * then result of route lookup is stored in ro->ro_rt.
 215  *
 216  * In the IP forwarding case, the packet will arrive with options already
 217  * inserted, so must have a NULL opt pointer.
 218  */
 219 int
 220 ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
 221     struct ip_moptions *imo, struct inpcb *inp)
 222 {
 223         struct rm_priotracker in_ifa_tracker;
 224         struct epoch_tracker et;
 225         struct ip *ip;
 226         struct ifnet *ifp = NULL;       /* keep compiler happy */
 227         struct mbuf *m0;
 228         int hlen = sizeof (struct ip);
 229         int mtu;
 230         int error = 0;
 231         struct sockaddr_in *dst, sin;
 232         const struct sockaddr_in *gw;
 233         struct in_ifaddr *ia;
 234         struct in_addr src;
 235         int isbroadcast;
 236         uint16_t ip_len, ip_off;
 237         uint32_t fibnum;
 238 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 239         int no_route_but_check_spd = 0;
 240 #endif
 241         M_ASSERTPKTHDR(m);
 242
 243         if (inp != NULL) {
 244                 INP_LOCK_ASSERT(inp);
 245                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 246                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 247                         m->m_pkthdr.flowid = inp->inp_flowid;
 248                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 249                 }
 250 #ifdef NUMA
 251                 m->m_pkthdr.numa_domain = inp->inp_numa_domain;
 252 #endif
 253         }
 254
 255         if (opt) {
 256                 int len = 0;
 257                 m = ip_insertoptions(m, opt, &len);
 258                 if (len != 0)
 259                         hlen = len; /* ip->ip_hl is updated above */
 260         }
 261         ip = mtod(m, struct ip *);
 262         ip_len = ntohs(ip->ip_len);
 263         ip_off = ntohs(ip->ip_off);
 264
 265         if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) {
 266                 ip->ip_v = IPVERSION;
 267                 ip->ip_hl = hlen >> 2;
 268                 ip_fillid(ip);
 269         } else {
 270                 /* Header already set, fetch hlen from there */
 271                 hlen = ip->ip_hl << 2;
 272         }
 273         if ((flags & IP_FORWARDING) == 0)
 274                 IPSTAT_INC(ips_localout);
 275
 276         /*
 277          * dst/gw handling:
 278          *
 279          * gw is readonly but can point either to dst OR rt_gateway,
 280          * therefore we need restore gw if we're redoing lookup.
 281          */
 282         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 283         if (ro != NULL)
 284                 dst = (struct sockaddr_in *)&ro->ro_dst;
 285         else
 286                 dst = &sin;
 287         if (ro == NULL || ro->ro_rt == NULL) {
 288                 bzero(dst, sizeof(*dst));
 289                 dst->sin_family = AF_INET;
 290                 dst->sin_len = sizeof(*dst);
 291                 dst->sin_addr = ip->ip_dst;
 292         }
 293         gw = dst;
 294         NET_EPOCH_ENTER(et);
 295 again:
 296         /*
 297          * Validate route against routing table additions;
 298          * a better/more specific route might have been added.
 299          */
 300         if (inp != NULL && ro != NULL && ro->ro_rt != NULL)
 301                 RT_VALIDATE(ro, &inp->inp_rt_cookie, fibnum);
 302         /*
 303          * If there is a cached route,
 304          * check that it is to the same destination
 305          * and is still up.  If not, free it and try again.
 306          * The address family should also be checked in case of sharing the
 307          * cache with IPv6.
 308          * Also check whether routing cache needs invalidation.
 309          */
 310         if (ro != NULL && ro->ro_rt != NULL &&
 311             ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
 312             ro->ro_rt->rt_ifp == NULL || !RT_LINK_IS_UP(ro->ro_rt->rt_ifp) ||
 313             dst->sin_family != AF_INET ||
 314             dst->sin_addr.s_addr != ip->ip_dst.s_addr))
 315                 RO_INVALIDATE_CACHE(ro);
 316         ia = NULL;
 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                 ip->ip_dst.s_addr = INADDR_BROADCAST;
 333                 dst->sin_addr = ip->ip_dst;
 334                 ifp = ia->ia_ifp;
 335                 mtu = ifp->if_mtu;
 336                 ip->ip_ttl = 1;
 337                 isbroadcast = 1;
 338                 src = IA_SIN(ia)->sin_addr;
 339         } else if (flags & IP_ROUTETOIF) {
 340                 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
 341                                                     M_GETFIB(m)))) == NULL &&
 342                     (ia = ifatoia(ifa_ifwithnet(sintosa(dst), 0,
 343                                                 M_GETFIB(m)))) == NULL) {
 344                         IPSTAT_INC(ips_noroute);
 345                         error = ENETUNREACH;
 346                         goto bad;
 347                 }
 348                 ifp = ia->ia_ifp;
 349                 mtu = ifp->if_mtu;
 350                 ip->ip_ttl = 1;
 351                 isbroadcast = ifp->if_flags & IFF_BROADCAST ?
 352                     in_ifaddr_broadcast(dst->sin_addr, ia) : 0;
 353                 src = IA_SIN(ia)->sin_addr;
 354         } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
 355             imo != NULL && imo->imo_multicast_ifp != NULL) {
 356                 /*
 357                  * Bypass the normal routing lookup for multicast
 358                  * packets if the interface is specified.
 359                  */
 360                 ifp = imo->imo_multicast_ifp;
 361                 mtu = ifp->if_mtu;
 362                 IFP_TO_IA(ifp, ia, &in_ifa_tracker);
 363                 isbroadcast = 0;        /* fool gcc */
 364                 /* Interface may have no addresses. */
 365                 if (ia != NULL)
 366                         src = IA_SIN(ia)->sin_addr;
 367                 else
 368                         src.s_addr = INADDR_ANY;
 369         } else if (ro != NULL) {
 370                 if (ro->ro_rt == NULL) {
 371                         /*
 372                          * We want to do any cloning requested by the link
 373                          * layer, as this is probably required in all cases
 374                          * for correct operation (as it is for ARP).
 375                          */
 376 #ifdef RADIX_MPATH
 377                         rtalloc_mpath_fib(ro,
 378                             ntohl(ip->ip_src.s_addr ^ ip->ip_dst.s_addr),
 379                             fibnum);
 380 #else
 381                         in_rtalloc_ign(ro, 0, fibnum);
 382 #endif
 383                         if (ro->ro_rt == NULL ||
 384                             (ro->ro_rt->rt_flags & RTF_UP) == 0 ||
 385                             ro->ro_rt->rt_ifp == NULL ||
 386                             !RT_LINK_IS_UP(ro->ro_rt->rt_ifp)) {
 387 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 388                                 /*
 389                                  * There is no route for this packet, but it is
 390                                  * possible that a matching SPD entry exists.
 391                                  */
 392                                 no_route_but_check_spd = 1;
 393                                 mtu = 0; /* Silence GCC warning. */
 394                                 goto sendit;
 395 #endif
 396                                 IPSTAT_INC(ips_noroute);
 397                                 error = EHOSTUNREACH;
 398                                 goto bad;
 399                         }
 400                 }
 401                 ia = ifatoia(ro->ro_rt->rt_ifa);
 402                 ifp = ro->ro_rt->rt_ifp;
 403                 counter_u64_add(ro->ro_rt->rt_pksent, 1);
 404                 rt_update_ro_flags(ro);
 405                 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
 406                         gw = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
 407                 if (ro->ro_rt->rt_flags & RTF_HOST)
 408                         isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST);
 409                 else if (ifp->if_flags & IFF_BROADCAST)
 410                         isbroadcast = in_ifaddr_broadcast(gw->sin_addr, ia);
 411                 else
 412                         isbroadcast = 0;
 413                 if (ro->ro_rt->rt_flags & RTF_HOST)
 414                         mtu = ro->ro_rt->rt_mtu;
 415                 else
 416                         mtu = ifp->if_mtu;
 417                 src = IA_SIN(ia)->sin_addr;
 418         } else {
 419                 struct nhop4_extended nh;
 420
 421                 bzero(&nh, sizeof(nh));
 422                 if (fib4_lookup_nh_ext(M_GETFIB(m), ip->ip_dst, 0, 0, &nh) !=
 423                     0) {
 424 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 425                         /*
 426                          * There is no route for this packet, but it is
 427                          * possible that a matching SPD entry exists.
 428                          */
 429                         no_route_but_check_spd = 1;
 430                         mtu = 0; /* Silence GCC warning. */
 431                         goto sendit;
 432 #endif
 433                         IPSTAT_INC(ips_noroute);
 434                         error = EHOSTUNREACH;
 435                         goto bad;
 436                 }
 437                 ifp = nh.nh_ifp;
 438                 mtu = nh.nh_mtu;
 439                 /*
 440                  * We are rewriting here dst to be gw actually, contradicting
 441                  * comment at the beginning of the function. However, in this
 442                  * case we are always dealing with on stack dst.
 443                  * In case if pfil(9) sends us back to beginning of the
 444                  * function, the dst would be rewritten by ip_output_pfil().
 445                  */
 446                 MPASS(dst == &sin);
 447                 dst->sin_addr = nh.nh_addr;
 448                 ia = nh.nh_ia;
 449                 src = nh.nh_src;
 450                 isbroadcast = (((nh.nh_flags & (NHF_HOST | NHF_BROADCAST)) ==
 451                     (NHF_HOST | NHF_BROADCAST)) ||
 452                     ((ifp->if_flags & IFF_BROADCAST) &&
 453                     in_ifaddr_broadcast(dst->sin_addr, ia)));
 454         }
 455
 456         /* Catch a possible divide by zero later. */
 457         KASSERT(mtu > 0, ("%s: mtu %d <= 0, ro=%p (rt_flags=0x%08x) ifp=%p",
 458             __func__, mtu, ro,
 459             (ro != NULL && ro->ro_rt != NULL) ? ro->ro_rt->rt_flags : 0, ifp));
 460
 461         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
 462                 m->m_flags |= M_MCAST;
 463                 /*
 464                  * IP destination address is multicast.  Make sure "gw"
 465                  * still points to the address in "ro".  (It may have been
 466                  * changed to point to a gateway address, above.)
 467                  */
 468                 gw = dst;
 469                 /*
 470                  * See if the caller provided any multicast options
 471                  */
 472                 if (imo != NULL) {
 473                         ip->ip_ttl = imo->imo_multicast_ttl;
 474                         if (imo->imo_multicast_vif != -1)
 475                                 ip->ip_src.s_addr =
 476                                     ip_mcast_src ?
 477                                     ip_mcast_src(imo->imo_multicast_vif) :
 478                                     INADDR_ANY;
 479                 } else
 480                         ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
 481                 /*
 482                  * Confirm that the outgoing interface supports multicast.
 483                  */
 484                 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
 485                         if ((ifp->if_flags & IFF_MULTICAST) == 0) {
 486                                 IPSTAT_INC(ips_noroute);
 487                                 error = ENETUNREACH;
 488                                 goto bad;
 489                         }
 490                 }
 491                 /*
 492                  * If source address not specified yet, use address
 493                  * of outgoing interface.
 494                  */
 495                 if (ip->ip_src.s_addr == INADDR_ANY)
 496                         ip->ip_src = src;
 497
 498                 if ((imo == NULL && in_mcast_loop) ||
 499                     (imo && imo->imo_multicast_loop)) {
 500                         /*
 501                          * Loop back multicast datagram if not expressly
 502                          * forbidden to do so, even if we are not a member
 503                          * of the group; ip_input() will filter it later,
 504                          * thus deferring a hash lookup and mutex acquisition
 505                          * at the expense of a cheap copy using m_copym().
 506                          */
 507                         ip_mloopback(ifp, m, hlen);
 508                 } else {
 509                         /*
 510                          * If we are acting as a multicast router, perform
 511                          * multicast forwarding as if the packet had just
 512                          * arrived on the interface to which we are about
 513                          * to send.  The multicast forwarding function
 514                          * recursively calls this function, using the
 515                          * IP_FORWARDING flag to prevent infinite recursion.
 516                          *
 517                          * Multicasts that are looped back by ip_mloopback(),
 518                          * above, will be forwarded by the ip_input() routine,
 519                          * if necessary.
 520                          */
 521                         if (V_ip_mrouter && (flags & IP_FORWARDING) == 0) {
 522                                 /*
 523                                  * If rsvp daemon is not running, do not
 524                                  * set ip_moptions. This ensures that the packet
 525                                  * is multicast and not just sent down one link
 526                                  * as prescribed by rsvpd.
 527                                  */
 528                                 if (!V_rsvp_on)
 529                                         imo = NULL;
 530                                 if (ip_mforward &&
 531                                     ip_mforward(ip, ifp, m, imo) != 0) {
 532                                         m_freem(m);
 533                                         goto done;
 534                                 }
 535                         }
 536                 }
 537
 538                 /*
 539                  * Multicasts with a time-to-live of zero may be looped-
 540                  * back, above, but must not be transmitted on a network.
 541                  * Also, multicasts addressed to the loopback interface
 542                  * are not sent -- the above call to ip_mloopback() will
 543                  * loop back a copy. ip_input() will drop the copy if
 544                  * this host does not belong to the destination group on
 545                  * the loopback interface.
 546                  */
 547                 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
 548                         m_freem(m);
 549                         goto done;
 550                 }
 551
 552                 goto sendit;
 553         }
 554
 555         /*
 556          * If the source address is not specified yet, use the address
 557          * of the outoing interface.
 558          */
 559         if (ip->ip_src.s_addr == INADDR_ANY)
 560                 ip->ip_src = src;
 561
 562         /*
 563          * Look for broadcast address and
 564          * verify user is allowed to send
 565          * such a packet.
 566          */
 567         if (isbroadcast) {
 568                 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
 569                         error = EADDRNOTAVAIL;
 570                         goto bad;
 571                 }
 572                 if ((flags & IP_ALLOWBROADCAST) == 0) {
 573                         error = EACCES;
 574                         goto bad;
 575                 }
 576                 /* don't allow broadcast messages to be fragmented */
 577                 if (ip_len > mtu) {
 578                         error = EMSGSIZE;
 579                         goto bad;
 580                 }
 581                 m->m_flags |= M_BCAST;
 582         } else {
 583                 m->m_flags &= ~M_BCAST;
 584         }
 585
 586 sendit:
 587 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 588         if (IPSEC_ENABLED(ipv4)) {
 589                 if ((error = IPSEC_OUTPUT(ipv4, m, inp)) != 0) {
 590                         if (error == EINPROGRESS)
 591                                 error = 0;
 592                         goto done;
 593                 }
 594         }
 595         /*
 596          * Check if there was a route for this packet; return error if not.
 597          */
 598         if (no_route_but_check_spd) {
 599                 IPSTAT_INC(ips_noroute);
 600                 error = EHOSTUNREACH;
 601                 goto bad;
 602         }
 603         /* Update variables that are affected by ipsec4_output(). */
 604         ip = mtod(m, struct ip *);
 605         hlen = ip->ip_hl << 2;
 606 #endif /* IPSEC */
 607
 608         /* Jump over all PFIL processing if hooks are not active. */
 609         if (PFIL_HOOKED_OUT(V_inet_pfil_head)) {
 610                 switch (ip_output_pfil(&m, ifp, inp, dst, &fibnum, &error)) {
 611                 case 1: /* Finished */
 612                         goto done;
 613
 614                 case 0: /* Continue normally */
 615                         ip = mtod(m, struct ip *);
 616                         break;
 617
 618                 case -1: /* Need to try again */
 619                         /* Reset everything for a new round */
 620                         if (ro != NULL) {
 621                                 RO_RTFREE(ro);
 622                                 ro->ro_prepend = NULL;
 623                         }
 624                         gw = dst;
 625                         ip = mtod(m, struct ip *);
 626                         goto again;
 627
 628                 }
 629         }
 630
 631         /* IN_LOOPBACK must not appear on the wire - RFC1122. */
 632         if (IN_LOOPBACK(ntohl(ip->ip_dst.s_addr)) ||
 633             IN_LOOPBACK(ntohl(ip->ip_src.s_addr))) {
 634                 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
 635                         IPSTAT_INC(ips_badaddr);
 636                         error = EADDRNOTAVAIL;
 637                         goto bad;
 638                 }
 639         }
 640
 641         m->m_pkthdr.csum_flags |= CSUM_IP;
 642         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
 643                 in_delayed_cksum(m);
 644                 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
 645         }
 646 #ifdef SCTP
 647         if (m->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
 648                 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
 649                 m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
 650         }
 651 #endif
 652
 653         /*
 654          * If small enough for interface, or the interface will take
 655          * care of the fragmentation for us, we can just send directly.
 656          */
 657         if (ip_len <= mtu ||
 658             (m->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0) {
 659                 ip->ip_sum = 0;
 660                 if (m->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
 661                         ip->ip_sum = in_cksum(m, hlen);
 662                         m->m_pkthdr.csum_flags &= ~CSUM_IP;
 663                 }
 664
 665                 /*
 666                  * Record statistics for this interface address.
 667                  * With CSUM_TSO the byte/packet count will be slightly
 668                  * incorrect because we count the IP+TCP headers only
 669                  * once instead of for every generated packet.
 670                  */
 671                 if (!(flags & IP_FORWARDING) && ia) {
 672                         if (m->m_pkthdr.csum_flags & CSUM_TSO)
 673                                 counter_u64_add(ia->ia_ifa.ifa_opackets,
 674                                     m->m_pkthdr.len / m->m_pkthdr.tso_segsz);
 675                         else
 676                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
 677
 678                         counter_u64_add(ia->ia_ifa.ifa_obytes, m->m_pkthdr.len);
 679                 }
 680 #ifdef MBUF_STRESS_TEST
 681                 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size)
 682                         m = m_fragment(m, M_NOWAIT, mbuf_frag_size);
 683 #endif
 684                 /*
 685                  * Reset layer specific mbuf flags
 686                  * to avoid confusing lower layers.
 687                  */
 688                 m_clrprotoflags(m);
 689                 IP_PROBE(send, NULL, NULL, ip, ifp, ip, NULL);
 690 #ifdef RATELIMIT
 691                 if (inp != NULL) {
 692                         if (inp->inp_flags2 & INP_RATE_LIMIT_CHANGED)
 693                                 in_pcboutput_txrtlmt(inp, ifp, m);
 694                         /* stamp send tag on mbuf */
 695                         m->m_pkthdr.snd_tag = inp->inp_snd_tag;
 696                 } else {
 697                         m->m_pkthdr.snd_tag = NULL;
 698                 }
 699 #endif
 700                 error = (*ifp->if_output)(ifp, m,
 701                     (const struct sockaddr *)gw, ro);
 702 #ifdef RATELIMIT
 703                 /* check for route change */
 704                 if (error == EAGAIN)
 705                         in_pcboutput_eagain(inp);
 706 #endif
 707                 goto done;
 708         }
 709
 710         /* Balk when DF bit is set or the interface didn't support TSO. */
 711         if ((ip_off & IP_DF) || (m->m_pkthdr.csum_flags & CSUM_TSO)) {
 712                 error = EMSGSIZE;
 713                 IPSTAT_INC(ips_cantfrag);
 714                 goto bad;
 715         }
 716
 717         /*
 718          * Too large for interface; fragment if possible. If successful,
 719          * on return, m will point to a list of packets to be sent.
 720          */
 721         error = ip_fragment(ip, &m, mtu, ifp->if_hwassist);
 722         if (error)
 723                 goto bad;
 724         for (; m; m = m0) {
 725                 m0 = m->m_nextpkt;
 726                 m->m_nextpkt = 0;
 727                 if (error == 0) {
 728                         /* Record statistics for this interface address. */
 729                         if (ia != NULL) {
 730                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
 731                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
 732                                     m->m_pkthdr.len);
 733                         }
 734                         /*
 735                          * Reset layer specific mbuf flags
 736                          * to avoid confusing upper layers.
 737                          */
 738                         m_clrprotoflags(m);
 739
 740                         IP_PROBE(send, NULL, NULL, mtod(m, struct ip *), ifp,
 741                             mtod(m, struct ip *), NULL);
 742 #ifdef RATELIMIT
 743                         if (inp != NULL) {
 744                                 if (inp->inp_flags2 & INP_RATE_LIMIT_CHANGED)
 745                                         in_pcboutput_txrtlmt(inp, ifp, m);
 746                                 /* stamp send tag on mbuf */
 747                                 m->m_pkthdr.snd_tag = inp->inp_snd_tag;
 748                         } else {
 749                                 m->m_pkthdr.snd_tag = NULL;
 750                         }
 751 #endif
 752                         error = (*ifp->if_output)(ifp, m,
 753                             (const struct sockaddr *)gw, ro);
 754 #ifdef RATELIMIT
 755                         /* check for route change */
 756                         if (error == EAGAIN)
 757                                 in_pcboutput_eagain(inp);
 758 #endif
 759                 } else
 760                         m_freem(m);
 761         }
 762
 763         if (error == 0)
 764                 IPSTAT_INC(ips_fragmented);
 765
 766 done:
 767         NET_EPOCH_EXIT(et);
 768         return (error);
 769  bad:
 770         m_freem(m);
 771         goto done;
 772 }
 773
 774 /*
 775  * Create a chain of fragments which fit the given mtu. m_frag points to the
 776  * mbuf to be fragmented; on return it points to the chain with the fragments.
 777  * Return 0 if no error. If error, m_frag may contain a partially built
 778  * chain of fragments that should be freed by the caller.
 779  *
 780  * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
 781  */
 782 int
 783 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
 784     u_long if_hwassist_flags)
 785 {
 786         int error = 0;
 787         int hlen = ip->ip_hl << 2;
 788         int len = (mtu - hlen) & ~7;    /* size of payload in each fragment */
 789         int off;
 790         struct mbuf *m0 = *m_frag;      /* the original packet          */
 791         int firstlen;
 792         struct mbuf **mnext;
 793         int nfrags;
 794         uint16_t ip_len, ip_off;
 795
 796         ip_len = ntohs(ip->ip_len);
 797         ip_off = ntohs(ip->ip_off);
 798
 799         if (ip_off & IP_DF) {   /* Fragmentation not allowed */
 800                 IPSTAT_INC(ips_cantfrag);
 801                 return EMSGSIZE;
 802         }
 803
 804         /*
 805          * Must be able to put at least 8 bytes per fragment.
 806          */
 807         if (len < 8)
 808                 return EMSGSIZE;
 809
 810         /*
 811          * If the interface will not calculate checksums on
 812          * fragmented packets, then do it here.
 813          */
 814         if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 815                 in_delayed_cksum(m0);
 816                 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
 817         }
 818 #ifdef SCTP
 819         if (m0->m_pkthdr.csum_flags & CSUM_SCTP) {
 820                 sctp_delayed_cksum(m0, hlen);
 821                 m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
 822         }
 823 #endif
 824         if (len > PAGE_SIZE) {
 825                 /*
 826                  * Fragment large datagrams such that each segment
 827                  * contains a multiple of PAGE_SIZE amount of data,
 828                  * plus headers. This enables a receiver to perform
 829                  * page-flipping zero-copy optimizations.
 830                  *
 831                  * XXX When does this help given that sender and receiver
 832                  * could have different page sizes, and also mtu could
 833                  * be less than the receiver's page size ?
 834                  */
 835                 int newlen;
 836
 837                 off = MIN(mtu, m0->m_pkthdr.len);
 838
 839                 /*
 840                  * firstlen (off - hlen) must be aligned on an
 841                  * 8-byte boundary
 842                  */
 843                 if (off < hlen)
 844                         goto smart_frag_failure;
 845                 off = ((off - hlen) & ~7) + hlen;
 846                 newlen = (~PAGE_MASK) & mtu;
 847                 if ((newlen + sizeof (struct ip)) > mtu) {
 848                         /* we failed, go back the default */
 849 smart_frag_failure:
 850                         newlen = len;
 851                         off = hlen + len;
 852                 }
 853                 len = newlen;
 854
 855         } else {
 856                 off = hlen + len;
 857         }
 858
 859         firstlen = off - hlen;
 860         mnext = &m0->m_nextpkt;         /* pointer to next packet */
 861
 862         /*
 863          * Loop through length of segment after first fragment,
 864          * make new header and copy data of each part and link onto chain.
 865          * Here, m0 is the original packet, m is the fragment being created.
 866          * The fragments are linked off the m_nextpkt of the original
 867          * packet, which after processing serves as the first fragment.
 868          */
 869         for (nfrags = 1; off < ip_len; off += len, nfrags++) {
 870                 struct ip *mhip;        /* ip header on the fragment */
 871                 struct mbuf *m;
 872                 int mhlen = sizeof (struct ip);
 873
 874                 m = m_gethdr(M_NOWAIT, MT_DATA);
 875                 if (m == NULL) {
 876                         error = ENOBUFS;
 877                         IPSTAT_INC(ips_odropped);
 878                         goto done;
 879                 }
 880                 /*
 881                  * Make sure the complete packet header gets copied
 882                  * from the originating mbuf to the newly created
 883                  * mbuf. This also ensures that existing firewall
 884                  * classification(s), VLAN tags and so on get copied
 885                  * to the resulting fragmented packet(s):
 886                  */
 887                 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
 888                         m_free(m);
 889                         error = ENOBUFS;
 890                         IPSTAT_INC(ips_odropped);
 891                         goto done;
 892                 }
 893                 /*
 894                  * In the first mbuf, leave room for the link header, then
 895                  * copy the original IP header including options. The payload
 896                  * goes into an additional mbuf chain returned by m_copym().
 897                  */
 898                 m->m_data += max_linkhdr;
 899                 mhip = mtod(m, struct ip *);
 900                 *mhip = *ip;
 901                 if (hlen > sizeof (struct ip)) {
 902                         mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
 903                         mhip->ip_v = IPVERSION;
 904                         mhip->ip_hl = mhlen >> 2;
 905                 }
 906                 m->m_len = mhlen;
 907                 /* XXX do we need to add ip_off below ? */
 908                 mhip->ip_off = ((off - hlen) >> 3) + ip_off;
 909                 if (off + len >= ip_len)
 910                         len = ip_len - off;
 911                 else
 912                         mhip->ip_off |= IP_MF;
 913                 mhip->ip_len = htons((u_short)(len + mhlen));
 914                 m->m_next = m_copym(m0, off, len, M_NOWAIT);
 915                 if (m->m_next == NULL) {        /* copy failed */
 916                         m_free(m);
 917                         error = ENOBUFS;        /* ??? */
 918                         IPSTAT_INC(ips_odropped);
 919                         goto done;
 920                 }
 921                 m->m_pkthdr.len = mhlen + len;
 922 #ifdef MAC
 923                 mac_netinet_fragment(m0, m);
 924 #endif
 925                 mhip->ip_off = htons(mhip->ip_off);
 926                 mhip->ip_sum = 0;
 927                 if (m->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
 928                         mhip->ip_sum = in_cksum(m, mhlen);
 929                         m->m_pkthdr.csum_flags &= ~CSUM_IP;
 930                 }
 931                 *mnext = m;
 932                 mnext = &m->m_nextpkt;
 933         }
 934         IPSTAT_ADD(ips_ofragments, nfrags);
 935
 936         /*
 937          * Update first fragment by trimming what's been copied out
 938          * and updating header.
 939          */
 940         m_adj(m0, hlen + firstlen - ip_len);
 941         m0->m_pkthdr.len = hlen + firstlen;
 942         ip->ip_len = htons((u_short)m0->m_pkthdr.len);
 943         ip->ip_off = htons(ip_off | IP_MF);
 944         ip->ip_sum = 0;
 945         if (m0->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
 946                 ip->ip_sum = in_cksum(m0, hlen);
 947                 m0->m_pkthdr.csum_flags &= ~CSUM_IP;
 948         }
 949
 950 done:
 951         *m_frag = m0;
 952         return error;
 953 }
 954
 955 void
 956 in_delayed_cksum(struct mbuf *m)
 957 {
 958         struct ip *ip;
 959         struct udphdr *uh;
 960         uint16_t cklen, csum, offset;
 961
 962         ip = mtod(m, struct ip *);
 963         offset = ip->ip_hl << 2 ;
 964
 965         if (m->m_pkthdr.csum_flags & CSUM_UDP) {
 966                 /* if udp header is not in the first mbuf copy udplen */
 967                 if (offset + sizeof(struct udphdr) > m->m_len) {
 968                         m_copydata(m, offset + offsetof(struct udphdr,
 969                             uh_ulen), sizeof(cklen), (caddr_t)&cklen);
 970                         cklen = ntohs(cklen);
 971                 } else {
 972                         uh = (struct udphdr *)mtodo(m, offset);
 973                         cklen = ntohs(uh->uh_ulen);
 974                 }
 975                 csum = in_cksum_skip(m, cklen + offset, offset);
 976                 if (csum == 0)
 977                         csum = 0xffff;
 978         } else {
 979                 cklen = ntohs(ip->ip_len);
 980                 csum = in_cksum_skip(m, cklen, offset);
 981         }
 982         offset += m->m_pkthdr.csum_data;        /* checksum offset */
 983
 984         if (offset + sizeof(csum) > m->m_len)
 985                 m_copyback(m, offset, sizeof(csum), (caddr_t)&csum);
 986         else
 987                 *(u_short *)mtodo(m, offset) = csum;
 988 }
 989
 990 /*
 991  * IP socket option processing.
 992  */
 993 int
 994 ip_ctloutput(struct socket *so, struct sockopt *sopt)
 995 {
 996         struct  inpcb *inp = sotoinpcb(so);
 997         int     error, optval;
 998 #ifdef  RSS
 999         uint32_t rss_bucket;
1000         int retval;
1001 #endif
1002
1003         error = optval = 0;
1004         if (sopt->sopt_level != IPPROTO_IP) {
1005                 error = EINVAL;
1006
1007                 if (sopt->sopt_level == SOL_SOCKET &&
1008                     sopt->sopt_dir == SOPT_SET) {
1009                         switch (sopt->sopt_name) {
1010                         case SO_REUSEADDR:
1011                                 INP_WLOCK(inp);
1012                                 if ((so->so_options & SO_REUSEADDR) != 0)
1013                                         inp->inp_flags2 |= INP_REUSEADDR;
1014                                 else
1015                                         inp->inp_flags2 &= ~INP_REUSEADDR;
1016                                 INP_WUNLOCK(inp);
1017                                 error = 0;
1018                                 break;
1019                         case SO_REUSEPORT:
1020                                 INP_WLOCK(inp);
1021                                 if ((so->so_options & SO_REUSEPORT) != 0)
1022                                         inp->inp_flags2 |= INP_REUSEPORT;
1023                                 else
1024                                         inp->inp_flags2 &= ~INP_REUSEPORT;
1025                                 INP_WUNLOCK(inp);
1026                                 error = 0;
1027                                 break;
1028                         case SO_REUSEPORT_LB:
1029                                 INP_WLOCK(inp);
1030                                 if ((so->so_options & SO_REUSEPORT_LB) != 0)
1031                                         inp->inp_flags2 |= INP_REUSEPORT_LB;
1032                                 else
1033                                         inp->inp_flags2 &= ~INP_REUSEPORT_LB;
1034                                 INP_WUNLOCK(inp);
1035                                 error = 0;
1036                                 break;
1037                         case SO_SETFIB:
1038                                 INP_WLOCK(inp);
1039                                 inp->inp_inc.inc_fibnum = so->so_fibnum;
1040                                 INP_WUNLOCK(inp);
1041                                 error = 0;
1042                                 break;
1043                         case SO_MAX_PACING_RATE:
1044 #ifdef RATELIMIT
1045                                 INP_WLOCK(inp);
1046                                 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1047                                 INP_WUNLOCK(inp);
1048                                 error = 0;
1049 #else
1050                                 error = EOPNOTSUPP;
1051 #endif
1052                                 break;
1053                         default:
1054                                 break;
1055                         }
1056                 }
1057                 return (error);
1058         }
1059
1060         switch (sopt->sopt_dir) {
1061         case SOPT_SET:
1062                 switch (sopt->sopt_name) {
1063                 case IP_OPTIONS:
1064 #ifdef notyet
1065                 case IP_RETOPTS:
1066 #endif
1067                 {
1068                         struct mbuf *m;
1069                         if (sopt->sopt_valsize > MLEN) {
1070                                 error = EMSGSIZE;
1071                                 break;
1072                         }
1073                         m = m_get(sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
1074                         if (m == NULL) {
1075                                 error = ENOBUFS;
1076                                 break;
1077                         }
1078                         m->m_len = sopt->sopt_valsize;
1079                         error = sooptcopyin(sopt, mtod(m, char *), m->m_len,
1080                                             m->m_len);
1081                         if (error) {
1082                                 m_free(m);
1083                                 break;
1084                         }
1085                         INP_WLOCK(inp);
1086                         error = ip_pcbopts(inp, sopt->sopt_name, m);
1087                         INP_WUNLOCK(inp);
1088                         return (error);
1089                 }
1090
1091                 case IP_BINDANY:
1092                         if (sopt->sopt_td != NULL) {
1093                                 error = priv_check(sopt->sopt_td,
1094                                     PRIV_NETINET_BINDANY);
1095                                 if (error)
1096                                         break;
1097                         }
1098                         /* FALLTHROUGH */
1099                 case IP_BINDMULTI:
1100 #ifdef  RSS
1101                 case IP_RSS_LISTEN_BUCKET:
1102 #endif
1103                 case IP_TOS:
1104                 case IP_TTL:
1105                 case IP_MINTTL:
1106                 case IP_RECVOPTS:
1107                 case IP_RECVRETOPTS:
1108                 case IP_ORIGDSTADDR:
1109                 case IP_RECVDSTADDR:
1110                 case IP_RECVTTL:
1111                 case IP_RECVIF:
1112                 case IP_ONESBCAST:
1113                 case IP_DONTFRAG:
1114                 case IP_RECVTOS:
1115                 case IP_RECVFLOWID:
1116 #ifdef  RSS
1117                 case IP_RECVRSSBUCKETID:
1118 #endif
1119                         error = sooptcopyin(sopt, &optval, sizeof optval,
1120                                             sizeof optval);
1121                         if (error)
1122                                 break;
1123
1124                         switch (sopt->sopt_name) {
1125                         case IP_TOS:
1126                                 inp->inp_ip_tos = optval;
1127                                 break;
1128
1129                         case IP_TTL:
1130                                 inp->inp_ip_ttl = optval;
1131                                 break;
1132
1133                         case IP_MINTTL:
1134                                 if (optval >= 0 && optval <= MAXTTL)
1135                                         inp->inp_ip_minttl = optval;
1136                                 else
1137                                         error = EINVAL;
1138                                 break;
1139
1140 #define OPTSET(bit) do {                                                \
1141         INP_WLOCK(inp);                                                 \
1142         if (optval)                                                     \
1143                 inp->inp_flags |= bit;                                  \
1144         else                                                            \
1145                 inp->inp_flags &= ~bit;                                 \
1146         INP_WUNLOCK(inp);                                               \
1147 } while (0)
1148
1149 #define OPTSET2(bit, val) do {                                          \
1150         INP_WLOCK(inp);                                                 \
1151         if (val)                                                        \
1152                 inp->inp_flags2 |= bit;                                 \
1153         else                                                            \
1154                 inp->inp_flags2 &= ~bit;                                \
1155         INP_WUNLOCK(inp);                                               \
1156 } while (0)
1157
1158                         case IP_RECVOPTS:
1159                                 OPTSET(INP_RECVOPTS);
1160                                 break;
1161
1162                         case IP_RECVRETOPTS:
1163                                 OPTSET(INP_RECVRETOPTS);
1164                                 break;
1165
1166                         case IP_RECVDSTADDR:
1167                                 OPTSET(INP_RECVDSTADDR);
1168                                 break;
1169
1170                         case IP_ORIGDSTADDR:
1171                                 OPTSET2(INP_ORIGDSTADDR, optval);
1172                                 break;
1173
1174                         case IP_RECVTTL:
1175                                 OPTSET(INP_RECVTTL);
1176                                 break;
1177
1178                         case IP_RECVIF:
1179                                 OPTSET(INP_RECVIF);
1180                                 break;
1181
1182                         case IP_ONESBCAST:
1183                                 OPTSET(INP_ONESBCAST);
1184                                 break;
1185                         case IP_DONTFRAG:
1186                                 OPTSET(INP_DONTFRAG);
1187                                 break;
1188                         case IP_BINDANY:
1189                                 OPTSET(INP_BINDANY);
1190                                 break;
1191                         case IP_RECVTOS:
1192                                 OPTSET(INP_RECVTOS);
1193                                 break;
1194                         case IP_BINDMULTI:
1195                                 OPTSET2(INP_BINDMULTI, optval);
1196                                 break;
1197                         case IP_RECVFLOWID:
1198                                 OPTSET2(INP_RECVFLOWID, optval);
1199                                 break;
1200 #ifdef  RSS
1201                         case IP_RSS_LISTEN_BUCKET:
1202                                 if ((optval >= 0) &&
1203                                     (optval < rss_getnumbuckets())) {
1204                                         inp->inp_rss_listen_bucket = optval;
1205                                         OPTSET2(INP_RSS_BUCKET_SET, 1);
1206                                 } else {
1207                                         error = EINVAL;
1208                                 }
1209                                 break;
1210                         case IP_RECVRSSBUCKETID:
1211                                 OPTSET2(INP_RECVRSSBUCKETID, optval);
1212                                 break;
1213 #endif
1214                         }
1215                         break;
1216 #undef OPTSET
1217 #undef OPTSET2
1218
1219                 /*
1220                  * Multicast socket options are processed by the in_mcast
1221                  * module.
1222                  */
1223                 case IP_MULTICAST_IF:
1224                 case IP_MULTICAST_VIF:
1225                 case IP_MULTICAST_TTL:
1226                 case IP_MULTICAST_LOOP:
1227                 case IP_ADD_MEMBERSHIP:
1228                 case IP_DROP_MEMBERSHIP:
1229                 case IP_ADD_SOURCE_MEMBERSHIP:
1230                 case IP_DROP_SOURCE_MEMBERSHIP:
1231                 case IP_BLOCK_SOURCE:
1232                 case IP_UNBLOCK_SOURCE:
1233                 case IP_MSFILTER:
1234                 case MCAST_JOIN_GROUP:
1235                 case MCAST_LEAVE_GROUP:
1236                 case MCAST_JOIN_SOURCE_GROUP:
1237                 case MCAST_LEAVE_SOURCE_GROUP:
1238                 case MCAST_BLOCK_SOURCE:
1239                 case MCAST_UNBLOCK_SOURCE:
1240                         error = inp_setmoptions(inp, sopt);
1241                         break;
1242
1243                 case IP_PORTRANGE:
1244                         error = sooptcopyin(sopt, &optval, sizeof optval,
1245                                             sizeof optval);
1246                         if (error)
1247                                 break;
1248
1249                         INP_WLOCK(inp);
1250                         switch (optval) {
1251                         case IP_PORTRANGE_DEFAULT:
1252                                 inp->inp_flags &= ~(INP_LOWPORT);
1253                                 inp->inp_flags &= ~(INP_HIGHPORT);
1254                                 break;
1255
1256                         case IP_PORTRANGE_HIGH:
1257                                 inp->inp_flags &= ~(INP_LOWPORT);
1258                                 inp->inp_flags |= INP_HIGHPORT;
1259                                 break;
1260
1261                         case IP_PORTRANGE_LOW:
1262                                 inp->inp_flags &= ~(INP_HIGHPORT);
1263                                 inp->inp_flags |= INP_LOWPORT;
1264                                 break;
1265
1266                         default:
1267                                 error = EINVAL;
1268                                 break;
1269                         }
1270                         INP_WUNLOCK(inp);
1271                         break;
1272
1273 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1274                 case IP_IPSEC_POLICY:
1275                         if (IPSEC_ENABLED(ipv4)) {
1276                                 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1277                                 break;
1278                         }
1279                         /* FALLTHROUGH */
1280 #endif /* IPSEC */
1281
1282                 default:
1283                         error = ENOPROTOOPT;
1284                         break;
1285                 }
1286                 break;
1287
1288         case SOPT_GET:
1289                 switch (sopt->sopt_name) {
1290                 case IP_OPTIONS:
1291                 case IP_RETOPTS:
1292                         INP_RLOCK(inp);
1293                         if (inp->inp_options) {
1294                                 struct mbuf *options;
1295
1296                                 options = m_copym(inp->inp_options, 0,
1297                                     M_COPYALL, M_NOWAIT);
1298                                 INP_RUNLOCK(inp);
1299                                 if (options != NULL) {
1300                                         error = sooptcopyout(sopt,
1301                                                              mtod(options, char *),
1302                                                              options->m_len);
1303                                         m_freem(options);
1304                                 } else
1305                                         error = ENOMEM;
1306                         } else {
1307                                 INP_RUNLOCK(inp);
1308                                 sopt->sopt_valsize = 0;
1309                         }
1310                         break;
1311
1312                 case IP_TOS:
1313                 case IP_TTL:
1314                 case IP_MINTTL:
1315                 case IP_RECVOPTS:
1316                 case IP_RECVRETOPTS:
1317                 case IP_ORIGDSTADDR:
1318                 case IP_RECVDSTADDR:
1319                 case IP_RECVTTL:
1320                 case IP_RECVIF:
1321                 case IP_PORTRANGE:
1322                 case IP_ONESBCAST:
1323                 case IP_DONTFRAG:
1324                 case IP_BINDANY:
1325                 case IP_RECVTOS:
1326                 case IP_BINDMULTI:
1327                 case IP_FLOWID:
1328                 case IP_FLOWTYPE:
1329                 case IP_RECVFLOWID:
1330 #ifdef  RSS
1331                 case IP_RSSBUCKETID:
1332                 case IP_RECVRSSBUCKETID:
1333 #endif
1334                         switch (sopt->sopt_name) {
1335
1336                         case IP_TOS:
1337                                 optval = inp->inp_ip_tos;
1338                                 break;
1339
1340                         case IP_TTL:
1341                                 optval = inp->inp_ip_ttl;
1342                                 break;
1343
1344                         case IP_MINTTL:
1345                                 optval = inp->inp_ip_minttl;
1346                                 break;
1347
1348 #define OPTBIT(bit)     (inp->inp_flags & bit ? 1 : 0)
1349 #define OPTBIT2(bit)    (inp->inp_flags2 & bit ? 1 : 0)
1350
1351                         case IP_RECVOPTS:
1352                                 optval = OPTBIT(INP_RECVOPTS);
1353                                 break;
1354
1355                         case IP_RECVRETOPTS:
1356                                 optval = OPTBIT(INP_RECVRETOPTS);
1357                                 break;
1358
1359                         case IP_RECVDSTADDR:
1360                                 optval = OPTBIT(INP_RECVDSTADDR);
1361                                 break;
1362
1363                         case IP_ORIGDSTADDR:
1364                                 optval = OPTBIT2(INP_ORIGDSTADDR);
1365                                 break;
1366
1367                         case IP_RECVTTL:
1368                                 optval = OPTBIT(INP_RECVTTL);
1369                                 break;
1370
1371                         case IP_RECVIF:
1372                                 optval = OPTBIT(INP_RECVIF);
1373                                 break;
1374
1375                         case IP_PORTRANGE:
1376                                 if (inp->inp_flags & INP_HIGHPORT)
1377                                         optval = IP_PORTRANGE_HIGH;
1378                                 else if (inp->inp_flags & INP_LOWPORT)
1379                                         optval = IP_PORTRANGE_LOW;
1380                                 else
1381                                         optval = 0;
1382                                 break;
1383
1384                         case IP_ONESBCAST:
1385                                 optval = OPTBIT(INP_ONESBCAST);
1386                                 break;
1387                         case IP_DONTFRAG:
1388                                 optval = OPTBIT(INP_DONTFRAG);
1389                                 break;
1390                         case IP_BINDANY:
1391                                 optval = OPTBIT(INP_BINDANY);
1392                                 break;
1393                         case IP_RECVTOS:
1394                                 optval = OPTBIT(INP_RECVTOS);
1395                                 break;
1396                         case IP_FLOWID:
1397                                 optval = inp->inp_flowid;
1398                                 break;
1399                         case IP_FLOWTYPE:
1400                                 optval = inp->inp_flowtype;
1401                                 break;
1402                         case IP_RECVFLOWID:
1403                                 optval = OPTBIT2(INP_RECVFLOWID);
1404                                 break;
1405 #ifdef  RSS
1406                         case IP_RSSBUCKETID:
1407                                 retval = rss_hash2bucket(inp->inp_flowid,
1408                                     inp->inp_flowtype,
1409                                     &rss_bucket);
1410                                 if (retval == 0)
1411                                         optval = rss_bucket;
1412                                 else
1413                                         error = EINVAL;
1414                                 break;
1415                         case IP_RECVRSSBUCKETID:
1416                                 optval = OPTBIT2(INP_RECVRSSBUCKETID);
1417                                 break;
1418 #endif
1419                         case IP_BINDMULTI:
1420                                 optval = OPTBIT2(INP_BINDMULTI);
1421                                 break;
1422                         }
1423                         error = sooptcopyout(sopt, &optval, sizeof optval);
1424                         break;
1425
1426                 /*
1427                  * Multicast socket options are processed by the in_mcast
1428                  * module.
1429                  */
1430                 case IP_MULTICAST_IF:
1431                 case IP_MULTICAST_VIF:
1432                 case IP_MULTICAST_TTL:
1433                 case IP_MULTICAST_LOOP:
1434                 case IP_MSFILTER:
1435                         error = inp_getmoptions(inp, sopt);
1436                         break;
1437
1438 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1439                 case IP_IPSEC_POLICY:
1440                         if (IPSEC_ENABLED(ipv4)) {
1441                                 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1442                                 break;
1443                         }
1444                         /* FALLTHROUGH */
1445 #endif /* IPSEC */
1446
1447                 default:
1448                         error = ENOPROTOOPT;
1449                         break;
1450                 }
1451                 break;
1452         }
1453         return (error);
1454 }
1455
1456 /*
1457  * Routine called from ip_output() to loop back a copy of an IP multicast
1458  * packet to the input queue of a specified interface.  Note that this
1459  * calls the output routine of the loopback "driver", but with an interface
1460  * pointer that might NOT be a loopback interface -- evil, but easier than
1461  * replicating that code here.
1462  */
1463 static void
1464 ip_mloopback(struct ifnet *ifp, const struct mbuf *m, int hlen)
1465 {
1466         struct ip *ip;
1467         struct mbuf *copym;
1468
1469         /*
1470          * Make a deep copy of the packet because we're going to
1471          * modify the pack in order to generate checksums.
1472          */
1473         copym = m_dup(m, M_NOWAIT);
1474         if (copym != NULL && (!M_WRITABLE(copym) || copym->m_len < hlen))
1475                 copym = m_pullup(copym, hlen);
1476         if (copym != NULL) {
1477                 /* If needed, compute the checksum and mark it as valid. */
1478                 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
1479                         in_delayed_cksum(copym);
1480                         copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1481                         copym->m_pkthdr.csum_flags |=
1482                             CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1483                         copym->m_pkthdr.csum_data = 0xffff;
1484                 }
1485                 /*
1486                  * We don't bother to fragment if the IP length is greater
1487                  * than the interface's MTU.  Can this possibly matter?
1488                  */
1489                 ip = mtod(copym, struct ip *);
1490                 ip->ip_sum = 0;
1491                 ip->ip_sum = in_cksum(copym, hlen);
1492                 if_simloop(ifp, copym, AF_INET, 0);
1493         }
1494 }