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_ratelimit.h"
  42 #include "opt_route.h"
  43 #include "opt_rss.h"
  44 #include "opt_sctp.h"
  45
  46 #include <sys/param.h>
  47 #include <sys/systm.h>
  48 #include <sys/kernel.h>
  49 #include <sys/ktls.h>
  50 #include <sys/lock.h>
  51 #include <sys/malloc.h>
  52 #include <sys/mbuf.h>
  53 #include <sys/priv.h>
  54 #include <sys/proc.h>
  55 #include <sys/protosw.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_vlan_var.h>
  65 #include <net/if_llatbl.h>
  66 #include <net/ethernet.h>
  67 #include <net/netisr.h>
  68 #include <net/pfil.h>
  69 #include <net/route.h>
  70 #include <net/route/nhop.h>
  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_fib.h>
  80 #include <netinet/in_pcb.h>
  81 #include <netinet/in_rss.h>
  82 #include <netinet/in_var.h>
  83 #include <netinet/ip_var.h>
  84 #include <netinet/ip_options.h>
  85
  86 #include <netinet/udp.h>
  87 #include <netinet/udp_var.h>
  88
  89 #if defined(SCTP) || defined(SCTP_SUPPORT)
  90 #include <netinet/sctp.h>
  91 #include <netinet/sctp_crc32.h>
  92 #endif
  93
  94 #include <netipsec/ipsec_support.h>
  95
  96 #include <machine/in_cksum.h>
  97
  98 #include <security/mac/mac_framework.h>
  99
 100 #ifdef MBUF_STRESS_TEST
 101 static int mbuf_frag_size = 0;
 102 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
 103         &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
 104 #endif
 105
 106 static void     ip_mloopback(struct ifnet *, const struct mbuf *, int);
 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, int flags,
 113     struct inpcb *inp, 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         int pflags = PFIL_OUT;
 120
 121         if (flags & IP_FORWARDING)
 122                 pflags |= PFIL_FWD;
 123
 124         m = *mp;
 125         ip = mtod(m, struct ip *);
 126
 127         /* Run through list of hooks for output packets. */
 128         odst.s_addr = ip->ip_dst.s_addr;
 129         switch (pfil_run_hooks(V_inet_pfil_head, mp, ifp, pflags, inp)) {
 130         case PFIL_DROPPED:
 131                 *error = EACCES;
 132                 /* FALLTHROUGH */
 133         case PFIL_CONSUMED:
 134                 return 1; /* Finished */
 135         case PFIL_PASS:
 136                 *error = 0;
 137         }
 138         m = *mp;
 139         ip = mtod(m, struct ip *);
 140
 141         /* See if destination IP address was changed by packet filter. */
 142         if (odst.s_addr != ip->ip_dst.s_addr) {
 143                 m->m_flags |= M_SKIP_FIREWALL;
 144                 /* If destination is now ourself drop to ip_input(). */
 145                 if (in_localip(ip->ip_dst)) {
 146                         m->m_flags |= M_FASTFWD_OURS;
 147                         if (m->m_pkthdr.rcvif == NULL)
 148                                 m->m_pkthdr.rcvif = V_loif;
 149                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 150                                 m->m_pkthdr.csum_flags |=
 151                                         CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
 152                                 m->m_pkthdr.csum_data = 0xffff;
 153                         }
 154                         m->m_pkthdr.csum_flags |=
 155                                 CSUM_IP_CHECKED | CSUM_IP_VALID;
 156 #if defined(SCTP) || defined(SCTP_SUPPORT)
 157                         if (m->m_pkthdr.csum_flags & CSUM_SCTP)
 158                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 159 #endif
 160                         *error = netisr_queue(NETISR_IP, m);
 161                         return 1; /* Finished */
 162                 }
 163
 164                 bzero(dst, sizeof(*dst));
 165                 dst->sin_family = AF_INET;
 166                 dst->sin_len = sizeof(*dst);
 167                 dst->sin_addr = ip->ip_dst;
 168
 169                 return -1; /* Reloop */
 170         }
 171         /* See if fib was changed by packet filter. */
 172         if ((*fibnum) != M_GETFIB(m)) {
 173                 m->m_flags |= M_SKIP_FIREWALL;
 174                 *fibnum = M_GETFIB(m);
 175                 return -1; /* Reloop for FIB change */
 176         }
 177
 178         /* See if local, if yes, send it to netisr with IP_FASTFWD_OURS. */
 179         if (m->m_flags & M_FASTFWD_OURS) {
 180                 if (m->m_pkthdr.rcvif == NULL)
 181                         m->m_pkthdr.rcvif = V_loif;
 182                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 183                         m->m_pkthdr.csum_flags |=
 184                                 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
 185                         m->m_pkthdr.csum_data = 0xffff;
 186                 }
 187 #if defined(SCTP) || defined(SCTP_SUPPORT)
 188                 if (m->m_pkthdr.csum_flags & CSUM_SCTP)
 189                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 190 #endif
 191                 m->m_pkthdr.csum_flags |=
 192                         CSUM_IP_CHECKED | CSUM_IP_VALID;
 193
 194                 *error = netisr_queue(NETISR_IP, m);
 195                 return 1; /* Finished */
 196         }
 197         /* Or forward to some other address? */
 198         if ((m->m_flags & M_IP_NEXTHOP) &&
 199             ((fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL)) {
 200                 bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in));
 201                 m->m_flags |= M_SKIP_FIREWALL;
 202                 m->m_flags &= ~M_IP_NEXTHOP;
 203                 m_tag_delete(m, fwd_tag);
 204
 205                 return -1; /* Reloop for CHANGE of dst */
 206         }
 207
 208         return 0;
 209 }
 210
 211 static int
 212 ip_output_send(struct inpcb *inp, struct ifnet *ifp, struct mbuf *m,
 213     const struct sockaddr *gw, struct route *ro, bool stamp_tag)
 214 {
 215 #ifdef KERN_TLS
 216         struct ktls_session *tls = NULL;
 217 #endif
 218         struct m_snd_tag *mst;
 219         int error;
 220
 221         MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0);
 222         mst = NULL;
 223
 224 #ifdef KERN_TLS
 225         /*
 226          * If this is an unencrypted TLS record, save a reference to
 227          * the record.  This local reference is used to call
 228          * ktls_output_eagain after the mbuf has been freed (thus
 229          * dropping the mbuf's reference) in if_output.
 230          */
 231         if (m->m_next != NULL && mbuf_has_tls_session(m->m_next)) {
 232                 tls = ktls_hold(m->m_next->m_epg_tls);
 233                 mst = tls->snd_tag;
 234
 235                 /*
 236                  * If a TLS session doesn't have a valid tag, it must
 237                  * have had an earlier ifp mismatch, so drop this
 238                  * packet.
 239                  */
 240                 if (mst == NULL) {
 241                         m_freem(m);
 242                         error = EAGAIN;
 243                         goto done;
 244                 }
 245                 /*
 246                  * Always stamp tags that include NIC ktls.
 247                  */
 248                 stamp_tag = true;
 249         }
 250 #endif
 251 #ifdef RATELIMIT
 252         if (inp != NULL && mst == NULL) {
 253                 if ((inp->inp_flags2 & INP_RATE_LIMIT_CHANGED) != 0 ||
 254                     (inp->inp_snd_tag != NULL &&
 255                     inp->inp_snd_tag->ifp != ifp))
 256                         in_pcboutput_txrtlmt(inp, ifp, m);
 257
 258                 if (inp->inp_snd_tag != NULL)
 259                         mst = inp->inp_snd_tag;
 260         }
 261 #endif
 262         if (stamp_tag && mst != NULL) {
 263                 KASSERT(m->m_pkthdr.rcvif == NULL,
 264                     ("trying to add a send tag to a forwarded packet"));
 265                 if (mst->ifp != ifp) {
 266                         m_freem(m);
 267                         error = EAGAIN;
 268                         goto done;
 269                 }
 270
 271                 /* stamp send tag on mbuf */
 272                 m->m_pkthdr.snd_tag = m_snd_tag_ref(mst);
 273                 m->m_pkthdr.csum_flags |= CSUM_SND_TAG;
 274         }
 275
 276         error = (*ifp->if_output)(ifp, m, gw, ro);
 277
 278 done:
 279         /* Check for route change invalidating send tags. */
 280 #ifdef KERN_TLS
 281         if (tls != NULL) {
 282                 if (error == EAGAIN)
 283                         error = ktls_output_eagain(inp, tls);
 284                 ktls_free(tls);
 285         }
 286 #endif
 287 #ifdef RATELIMIT
 288         if (error == EAGAIN)
 289                 in_pcboutput_eagain(inp);
 290 #endif
 291         return (error);
 292 }
 293
 294 /* rte<>ro_flags translation */
 295 static inline void
 296 rt_update_ro_flags(struct route *ro, const struct nhop_object *nh)
 297 {
 298         int nh_flags = nh->nh_flags;
 299
 300         ro->ro_flags &= ~ (RT_REJECT|RT_BLACKHOLE|RT_HAS_GW);
 301
 302         ro->ro_flags |= (nh_flags & NHF_REJECT) ? RT_REJECT : 0;
 303         ro->ro_flags |= (nh_flags & NHF_BLACKHOLE) ? RT_BLACKHOLE : 0;
 304         ro->ro_flags |= (nh_flags & NHF_GATEWAY) ? RT_HAS_GW : 0;
 305 }
 306
 307 /*
 308  * IP output.  The packet in mbuf chain m contains a skeletal IP
 309  * header (with len, off, ttl, proto, tos, src, dst).
 310  * The mbuf chain containing the packet will be freed.
 311  * The mbuf opt, if present, will not be freed.
 312  * If route ro is present and has ro_rt initialized, route lookup would be
 313  * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
 314  * then result of route lookup is stored in ro->ro_rt.
 315  *
 316  * In the IP forwarding case, the packet will arrive with options already
 317  * inserted, so must have a NULL opt pointer.
 318  */
 319 int
 320 ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
 321     struct ip_moptions *imo, struct inpcb *inp)
 322 {
 323         struct ip *ip;
 324         struct ifnet *ifp = NULL;       /* keep compiler happy */
 325         struct mbuf *m0;
 326         int hlen = sizeof (struct ip);
 327         int mtu = 0;
 328         int error = 0;
 329         int vlan_pcp = -1;
 330         struct sockaddr_in *dst;
 331         const struct sockaddr *gw;
 332         struct in_ifaddr *ia = NULL;
 333         struct in_addr src;
 334         int isbroadcast;
 335         uint16_t ip_len, ip_off;
 336         struct route iproute;
 337         uint32_t fibnum;
 338 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 339         int no_route_but_check_spd = 0;
 340 #endif
 341
 342         M_ASSERTPKTHDR(m);
 343         NET_EPOCH_ASSERT();
 344
 345         if (inp != NULL) {
 346                 INP_LOCK_ASSERT(inp);
 347                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 348                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 349                         m->m_pkthdr.flowid = inp->inp_flowid;
 350                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 351                 }
 352                 if ((inp->inp_flags2 & INP_2PCP_SET) != 0)
 353                         vlan_pcp = (inp->inp_flags2 & INP_2PCP_MASK) >>
 354                             INP_2PCP_SHIFT;
 355 #ifdef NUMA
 356                 m->m_pkthdr.numa_domain = inp->inp_numa_domain;
 357 #endif
 358         }
 359
 360         if (opt) {
 361                 int len = 0;
 362                 m = ip_insertoptions(m, opt, &len);
 363                 if (len != 0)
 364                         hlen = len; /* ip->ip_hl is updated above */
 365         }
 366         ip = mtod(m, struct ip *);
 367         ip_len = ntohs(ip->ip_len);
 368         ip_off = ntohs(ip->ip_off);
 369
 370         if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) {
 371                 ip->ip_v = IPVERSION;
 372                 ip->ip_hl = hlen >> 2;
 373                 ip_fillid(ip);
 374         } else {
 375                 /* Header already set, fetch hlen from there */
 376                 hlen = ip->ip_hl << 2;
 377         }
 378         if ((flags & IP_FORWARDING) == 0)
 379                 IPSTAT_INC(ips_localout);
 380
 381         /*
 382          * dst/gw handling:
 383          *
 384          * gw is readonly but can point either to dst OR rt_gateway,
 385          * therefore we need restore gw if we're redoing lookup.
 386          */
 387         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 388         if (ro == NULL) {
 389                 ro = &iproute;
 390                 bzero(ro, sizeof (*ro));
 391         }
 392         dst = (struct sockaddr_in *)&ro->ro_dst;
 393         if (ro->ro_nh == NULL) {
 394                 dst->sin_family = AF_INET;
 395                 dst->sin_len = sizeof(*dst);
 396                 dst->sin_addr = ip->ip_dst;
 397         }
 398         gw = (const struct sockaddr *)dst;
 399 again:
 400         /*
 401          * Validate route against routing table additions;
 402          * a better/more specific route might have been added.
 403          */
 404         if (inp != NULL && ro->ro_nh != NULL)
 405                 NH_VALIDATE(ro, &inp->inp_rt_cookie, fibnum);
 406         /*
 407          * If there is a cached route,
 408          * check that it is to the same destination
 409          * and is still up.  If not, free it and try again.
 410          * The address family should also be checked in case of sharing the
 411          * cache with IPv6.
 412          * Also check whether routing cache needs invalidation.
 413          */
 414         if (ro->ro_nh != NULL &&
 415             ((!NH_IS_VALID(ro->ro_nh)) || dst->sin_family != AF_INET ||
 416             dst->sin_addr.s_addr != ip->ip_dst.s_addr))
 417                 RO_INVALIDATE_CACHE(ro);
 418         ia = NULL;
 419         /*
 420          * If routing to interface only, short circuit routing lookup.
 421          * The use of an all-ones broadcast address implies this; an
 422          * interface is specified by the broadcast address of an interface,
 423          * or the destination address of a ptp interface.
 424          */
 425         if (flags & IP_SENDONES) {
 426                 if ((ia = ifatoia(ifa_ifwithbroadaddr(sintosa(dst),
 427                                                       M_GETFIB(m)))) == NULL &&
 428                     (ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
 429                                                     M_GETFIB(m)))) == NULL) {
 430                         IPSTAT_INC(ips_noroute);
 431                         error = ENETUNREACH;
 432                         goto bad;
 433                 }
 434                 ip->ip_dst.s_addr = INADDR_BROADCAST;
 435                 dst->sin_addr = ip->ip_dst;
 436                 ifp = ia->ia_ifp;
 437                 mtu = ifp->if_mtu;
 438                 ip->ip_ttl = 1;
 439                 isbroadcast = 1;
 440                 src = IA_SIN(ia)->sin_addr;
 441         } else if (flags & IP_ROUTETOIF) {
 442                 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
 443                                                     M_GETFIB(m)))) == NULL &&
 444                     (ia = ifatoia(ifa_ifwithnet(sintosa(dst), 0,
 445                                                 M_GETFIB(m)))) == NULL) {
 446                         IPSTAT_INC(ips_noroute);
 447                         error = ENETUNREACH;
 448                         goto bad;
 449                 }
 450                 ifp = ia->ia_ifp;
 451                 mtu = ifp->if_mtu;
 452                 ip->ip_ttl = 1;
 453                 isbroadcast = ifp->if_flags & IFF_BROADCAST ?
 454                     in_ifaddr_broadcast(dst->sin_addr, ia) : 0;
 455                 src = IA_SIN(ia)->sin_addr;
 456         } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
 457             imo != NULL && imo->imo_multicast_ifp != NULL) {
 458                 /*
 459                  * Bypass the normal routing lookup for multicast
 460                  * packets if the interface is specified.
 461                  */
 462                 ifp = imo->imo_multicast_ifp;
 463                 mtu = ifp->if_mtu;
 464                 IFP_TO_IA(ifp, ia);
 465                 isbroadcast = 0;        /* fool gcc */
 466                 /* Interface may have no addresses. */
 467                 if (ia != NULL)
 468                         src = IA_SIN(ia)->sin_addr;
 469                 else
 470                         src.s_addr = INADDR_ANY;
 471         } else if (ro != &iproute) {
 472                 if (ro->ro_nh == NULL) {
 473                         /*
 474                          * We want to do any cloning requested by the link
 475                          * layer, as this is probably required in all cases
 476                          * for correct operation (as it is for ARP).
 477                          */
 478                         uint32_t flowid;
 479                         flowid = m->m_pkthdr.flowid;
 480                         ro->ro_nh = fib4_lookup(fibnum, dst->sin_addr, 0,
 481                             NHR_REF, flowid);
 482
 483                         if (ro->ro_nh == NULL || (!NH_IS_VALID(ro->ro_nh))) {
 484 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 485                                 /*
 486                                  * There is no route for this packet, but it is
 487                                  * possible that a matching SPD entry exists.
 488                                  */
 489                                 no_route_but_check_spd = 1;
 490                                 goto sendit;
 491 #endif
 492                                 IPSTAT_INC(ips_noroute);
 493                                 error = EHOSTUNREACH;
 494                                 goto bad;
 495                         }
 496                 }
 497                 struct nhop_object *nh = ro->ro_nh;
 498
 499                 ia = ifatoia(nh->nh_ifa);
 500                 ifp = nh->nh_ifp;
 501                 counter_u64_add(nh->nh_pksent, 1);
 502                 rt_update_ro_flags(ro, nh);
 503                 if (nh->nh_flags & NHF_GATEWAY)
 504                         gw = &nh->gw_sa;
 505                 if (nh->nh_flags & NHF_HOST)
 506                         isbroadcast = (nh->nh_flags & NHF_BROADCAST);
 507                 else if ((ifp->if_flags & IFF_BROADCAST) && (gw->sa_family == AF_INET))
 508                         isbroadcast = in_ifaddr_broadcast(((const struct sockaddr_in *)gw)->sin_addr, ia);
 509                 else
 510                         isbroadcast = 0;
 511                 mtu = nh->nh_mtu;
 512                 src = IA_SIN(ia)->sin_addr;
 513         } else {
 514                 struct nhop_object *nh;
 515
 516                 nh = fib4_lookup(M_GETFIB(m), dst->sin_addr, 0, NHR_NONE,
 517                     m->m_pkthdr.flowid);
 518                 if (nh == NULL) {
 519 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 520                         /*
 521                          * There is no route for this packet, but it is
 522                          * possible that a matching SPD entry exists.
 523                          */
 524                         no_route_but_check_spd = 1;
 525                         goto sendit;
 526 #endif
 527                         IPSTAT_INC(ips_noroute);
 528                         error = EHOSTUNREACH;
 529                         goto bad;
 530                 }
 531                 ifp = nh->nh_ifp;
 532                 mtu = nh->nh_mtu;
 533                 rt_update_ro_flags(ro, nh);
 534                 if (nh->nh_flags & NHF_GATEWAY)
 535                         gw = &nh->gw_sa;
 536                 ia = ifatoia(nh->nh_ifa);
 537                 src = IA_SIN(ia)->sin_addr;
 538                 isbroadcast = (((nh->nh_flags & (NHF_HOST | NHF_BROADCAST)) ==
 539                     (NHF_HOST | NHF_BROADCAST)) ||
 540                     ((ifp->if_flags & IFF_BROADCAST) &&
 541                     (gw->sa_family == AF_INET) &&
 542                     in_ifaddr_broadcast(((const struct sockaddr_in *)gw)->sin_addr, ia)));
 543         }
 544
 545         /* Catch a possible divide by zero later. */
 546         KASSERT(mtu > 0, ("%s: mtu %d <= 0, ro=%p (nh_flags=0x%08x) ifp=%p",
 547             __func__, mtu, ro,
 548             (ro != NULL && ro->ro_nh != NULL) ? ro->ro_nh->nh_flags : 0, ifp));
 549
 550         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
 551                 m->m_flags |= M_MCAST;
 552                 /*
 553                  * IP destination address is multicast.  Make sure "gw"
 554                  * still points to the address in "ro".  (It may have been
 555                  * changed to point to a gateway address, above.)
 556                  */
 557                 gw = (const struct sockaddr *)dst;
 558                 /*
 559                  * See if the caller provided any multicast options
 560                  */
 561                 if (imo != NULL) {
 562                         ip->ip_ttl = imo->imo_multicast_ttl;
 563                         if (imo->imo_multicast_vif != -1)
 564                                 ip->ip_src.s_addr =
 565                                     ip_mcast_src ?
 566                                     ip_mcast_src(imo->imo_multicast_vif) :
 567                                     INADDR_ANY;
 568                 } else
 569                         ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
 570                 /*
 571                  * Confirm that the outgoing interface supports multicast.
 572                  */
 573                 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
 574                         if ((ifp->if_flags & IFF_MULTICAST) == 0) {
 575                                 IPSTAT_INC(ips_noroute);
 576                                 error = ENETUNREACH;
 577                                 goto bad;
 578                         }
 579                 }
 580                 /*
 581                  * If source address not specified yet, use address
 582                  * of outgoing interface.
 583                  */
 584                 if (ip->ip_src.s_addr == INADDR_ANY)
 585                         ip->ip_src = src;
 586
 587                 if ((imo == NULL && in_mcast_loop) ||
 588                     (imo && imo->imo_multicast_loop)) {
 589                         /*
 590                          * Loop back multicast datagram if not expressly
 591                          * forbidden to do so, even if we are not a member
 592                          * of the group; ip_input() will filter it later,
 593                          * thus deferring a hash lookup and mutex acquisition
 594                          * at the expense of a cheap copy using m_copym().
 595                          */
 596                         ip_mloopback(ifp, m, hlen);
 597                 } else {
 598                         /*
 599                          * If we are acting as a multicast router, perform
 600                          * multicast forwarding as if the packet had just
 601                          * arrived on the interface to which we are about
 602                          * to send.  The multicast forwarding function
 603                          * recursively calls this function, using the
 604                          * IP_FORWARDING flag to prevent infinite recursion.
 605                          *
 606                          * Multicasts that are looped back by ip_mloopback(),
 607                          * above, will be forwarded by the ip_input() routine,
 608                          * if necessary.
 609                          */
 610                         if (V_ip_mrouter && (flags & IP_FORWARDING) == 0) {
 611                                 /*
 612                                  * If rsvp daemon is not running, do not
 613                                  * set ip_moptions. This ensures that the packet
 614                                  * is multicast and not just sent down one link
 615                                  * as prescribed by rsvpd.
 616                                  */
 617                                 if (!V_rsvp_on)
 618                                         imo = NULL;
 619                                 if (ip_mforward &&
 620                                     ip_mforward(ip, ifp, m, imo) != 0) {
 621                                         m_freem(m);
 622                                         goto done;
 623                                 }
 624                         }
 625                 }
 626
 627                 /*
 628                  * Multicasts with a time-to-live of zero may be looped-
 629                  * back, above, but must not be transmitted on a network.
 630                  * Also, multicasts addressed to the loopback interface
 631                  * are not sent -- the above call to ip_mloopback() will
 632                  * loop back a copy. ip_input() will drop the copy if
 633                  * this host does not belong to the destination group on
 634                  * the loopback interface.
 635                  */
 636                 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
 637                         m_freem(m);
 638                         goto done;
 639                 }
 640
 641                 goto sendit;
 642         }
 643
 644         /*
 645          * If the source address is not specified yet, use the address
 646          * of the outoing interface.
 647          */
 648         if (ip->ip_src.s_addr == INADDR_ANY)
 649                 ip->ip_src = src;
 650
 651         /*
 652          * Look for broadcast address and
 653          * verify user is allowed to send
 654          * such a packet.
 655          */
 656         if (isbroadcast) {
 657                 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
 658                         error = EADDRNOTAVAIL;
 659                         goto bad;
 660                 }
 661                 if ((flags & IP_ALLOWBROADCAST) == 0) {
 662                         error = EACCES;
 663                         goto bad;
 664                 }
 665                 /* don't allow broadcast messages to be fragmented */
 666                 if (ip_len > mtu) {
 667                         error = EMSGSIZE;
 668                         goto bad;
 669                 }
 670                 m->m_flags |= M_BCAST;
 671         } else {
 672                 m->m_flags &= ~M_BCAST;
 673         }
 674
 675 sendit:
 676 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 677         if (IPSEC_ENABLED(ipv4)) {
 678                 if ((error = IPSEC_OUTPUT(ipv4, m, inp)) != 0) {
 679                         if (error == EINPROGRESS)
 680                                 error = 0;
 681                         goto done;
 682                 }
 683         }
 684         /*
 685          * Check if there was a route for this packet; return error if not.
 686          */
 687         if (no_route_but_check_spd) {
 688                 IPSTAT_INC(ips_noroute);
 689                 error = EHOSTUNREACH;
 690                 goto bad;
 691         }
 692         /* Update variables that are affected by ipsec4_output(). */
 693         ip = mtod(m, struct ip *);
 694         hlen = ip->ip_hl << 2;
 695 #endif /* IPSEC */
 696
 697         /* Jump over all PFIL processing if hooks are not active. */
 698         if (PFIL_HOOKED_OUT(V_inet_pfil_head)) {
 699                 switch (ip_output_pfil(&m, ifp, flags, inp, dst, &fibnum,
 700                     &error)) {
 701                 case 1: /* Finished */
 702                         goto done;
 703
 704                 case 0: /* Continue normally */
 705                         ip = mtod(m, struct ip *);
 706                         break;
 707
 708                 case -1: /* Need to try again */
 709                         /* Reset everything for a new round */
 710                         if (ro != NULL) {
 711                                 RO_NHFREE(ro);
 712                                 ro->ro_prepend = NULL;
 713                         }
 714                         gw = (const struct sockaddr *)dst;
 715                         ip = mtod(m, struct ip *);
 716                         goto again;
 717                 }
 718         }
 719
 720         if (vlan_pcp > -1)
 721                 EVL_APPLY_PRI(m, vlan_pcp);
 722
 723         /* IN_LOOPBACK must not appear on the wire - RFC1122. */
 724         if (IN_LOOPBACK(ntohl(ip->ip_dst.s_addr)) ||
 725             IN_LOOPBACK(ntohl(ip->ip_src.s_addr))) {
 726                 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
 727                         IPSTAT_INC(ips_badaddr);
 728                         error = EADDRNOTAVAIL;
 729                         goto bad;
 730                 }
 731         }
 732
 733         /* Ensure the packet data is mapped if the interface requires it. */
 734         if ((ifp->if_capenable & IFCAP_MEXTPG) == 0) {
 735                 m = mb_unmapped_to_ext(m);
 736                 if (m == NULL) {
 737                         IPSTAT_INC(ips_odropped);
 738                         error = ENOBUFS;
 739                         goto bad;
 740                 }
 741         }
 742
 743         m->m_pkthdr.csum_flags |= CSUM_IP;
 744         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
 745                 in_delayed_cksum(m);
 746                 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
 747         }
 748 #if defined(SCTP) || defined(SCTP_SUPPORT)
 749         if (m->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
 750                 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
 751                 m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
 752         }
 753 #endif
 754
 755         /*
 756          * If small enough for interface, or the interface will take
 757          * care of the fragmentation for us, we can just send directly.
 758          * Note that if_vxlan could have requested TSO even though the outer
 759          * frame is UDP.  It is correct to not fragment such datagrams and
 760          * instead just pass them on to the driver.
 761          */
 762         if (ip_len <= mtu ||
 763             (m->m_pkthdr.csum_flags & ifp->if_hwassist &
 764             (CSUM_TSO | CSUM_INNER_TSO)) != 0) {
 765                 ip->ip_sum = 0;
 766                 if (m->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
 767                         ip->ip_sum = in_cksum(m, hlen);
 768                         m->m_pkthdr.csum_flags &= ~CSUM_IP;
 769                 }
 770
 771                 /*
 772                  * Record statistics for this interface address.
 773                  * With CSUM_TSO the byte/packet count will be slightly
 774                  * incorrect because we count the IP+TCP headers only
 775                  * once instead of for every generated packet.
 776                  */
 777                 if (!(flags & IP_FORWARDING) && ia) {
 778                         if (m->m_pkthdr.csum_flags &
 779                             (CSUM_TSO | CSUM_INNER_TSO))
 780                                 counter_u64_add(ia->ia_ifa.ifa_opackets,
 781                                     m->m_pkthdr.len / m->m_pkthdr.tso_segsz);
 782                         else
 783                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
 784
 785                         counter_u64_add(ia->ia_ifa.ifa_obytes, m->m_pkthdr.len);
 786                 }
 787 #ifdef MBUF_STRESS_TEST
 788                 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size)
 789                         m = m_fragment(m, M_NOWAIT, mbuf_frag_size);
 790 #endif
 791                 /*
 792                  * Reset layer specific mbuf flags
 793                  * to avoid confusing lower layers.
 794                  */
 795                 m_clrprotoflags(m);
 796                 IP_PROBE(send, NULL, NULL, ip, ifp, ip, NULL);
 797                 error = ip_output_send(inp, ifp, m, gw, ro,
 798                     (flags & IP_NO_SND_TAG_RL) ? false : true);
 799                 goto done;
 800         }
 801
 802         /* Balk when DF bit is set or the interface didn't support TSO. */
 803         if ((ip_off & IP_DF) ||
 804             (m->m_pkthdr.csum_flags & (CSUM_TSO | CSUM_INNER_TSO))) {
 805                 error = EMSGSIZE;
 806                 IPSTAT_INC(ips_cantfrag);
 807                 goto bad;
 808         }
 809
 810         /*
 811          * Too large for interface; fragment if possible. If successful,
 812          * on return, m will point to a list of packets to be sent.
 813          */
 814         error = ip_fragment(ip, &m, mtu, ifp->if_hwassist);
 815         if (error)
 816                 goto bad;
 817         for (; m; m = m0) {
 818                 m0 = m->m_nextpkt;
 819                 m->m_nextpkt = 0;
 820                 if (error == 0) {
 821                         /* Record statistics for this interface address. */
 822                         if (ia != NULL) {
 823                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
 824                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
 825                                     m->m_pkthdr.len);
 826                         }
 827                         /*
 828                          * Reset layer specific mbuf flags
 829                          * to avoid confusing upper layers.
 830                          */
 831                         m_clrprotoflags(m);
 832
 833                         IP_PROBE(send, NULL, NULL, mtod(m, struct ip *), ifp,
 834                             mtod(m, struct ip *), NULL);
 835                         error = ip_output_send(inp, ifp, m, gw, ro, true);
 836                 } else
 837                         m_freem(m);
 838         }
 839
 840         if (error == 0)
 841                 IPSTAT_INC(ips_fragmented);
 842
 843 done:
 844         return (error);
 845  bad:
 846         m_freem(m);
 847         goto done;
 848 }
 849
 850 /*
 851  * Create a chain of fragments which fit the given mtu. m_frag points to the
 852  * mbuf to be fragmented; on return it points to the chain with the fragments.
 853  * Return 0 if no error. If error, m_frag may contain a partially built
 854  * chain of fragments that should be freed by the caller.
 855  *
 856  * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
 857  */
 858 int
 859 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
 860     u_long if_hwassist_flags)
 861 {
 862         int error = 0;
 863         int hlen = ip->ip_hl << 2;
 864         int len = (mtu - hlen) & ~7;    /* size of payload in each fragment */
 865         int off;
 866         struct mbuf *m0 = *m_frag;      /* the original packet          */
 867         int firstlen;
 868         struct mbuf **mnext;
 869         int nfrags;
 870         uint16_t ip_len, ip_off;
 871
 872         ip_len = ntohs(ip->ip_len);
 873         ip_off = ntohs(ip->ip_off);
 874
 875         if (ip_off & IP_DF) {   /* Fragmentation not allowed */
 876                 IPSTAT_INC(ips_cantfrag);
 877                 return EMSGSIZE;
 878         }
 879
 880         /*
 881          * Must be able to put at least 8 bytes per fragment.
 882          */
 883         if (len < 8)
 884                 return EMSGSIZE;
 885
 886         /*
 887          * If the interface will not calculate checksums on
 888          * fragmented packets, then do it here.
 889          */
 890         if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 891                 in_delayed_cksum(m0);
 892                 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
 893         }
 894 #if defined(SCTP) || defined(SCTP_SUPPORT)
 895         if (m0->m_pkthdr.csum_flags & CSUM_SCTP) {
 896                 sctp_delayed_cksum(m0, hlen);
 897                 m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
 898         }
 899 #endif
 900         if (len > PAGE_SIZE) {
 901                 /*
 902                  * Fragment large datagrams such that each segment
 903                  * contains a multiple of PAGE_SIZE amount of data,
 904                  * plus headers. This enables a receiver to perform
 905                  * page-flipping zero-copy optimizations.
 906                  *
 907                  * XXX When does this help given that sender and receiver
 908                  * could have different page sizes, and also mtu could
 909                  * be less than the receiver's page size ?
 910                  */
 911                 int newlen;
 912
 913                 off = MIN(mtu, m0->m_pkthdr.len);
 914
 915                 /*
 916                  * firstlen (off - hlen) must be aligned on an
 917                  * 8-byte boundary
 918                  */
 919                 if (off < hlen)
 920                         goto smart_frag_failure;
 921                 off = ((off - hlen) & ~7) + hlen;
 922                 newlen = (~PAGE_MASK) & mtu;
 923                 if ((newlen + sizeof (struct ip)) > mtu) {
 924                         /* we failed, go back the default */
 925 smart_frag_failure:
 926                         newlen = len;
 927                         off = hlen + len;
 928                 }
 929                 len = newlen;
 930
 931         } else {
 932                 off = hlen + len;
 933         }
 934
 935         firstlen = off - hlen;
 936         mnext = &m0->m_nextpkt;         /* pointer to next packet */
 937
 938         /*
 939          * Loop through length of segment after first fragment,
 940          * make new header and copy data of each part and link onto chain.
 941          * Here, m0 is the original packet, m is the fragment being created.
 942          * The fragments are linked off the m_nextpkt of the original
 943          * packet, which after processing serves as the first fragment.
 944          */
 945         for (nfrags = 1; off < ip_len; off += len, nfrags++) {
 946                 struct ip *mhip;        /* ip header on the fragment */
 947                 struct mbuf *m;
 948                 int mhlen = sizeof (struct ip);
 949
 950                 m = m_gethdr(M_NOWAIT, MT_DATA);
 951                 if (m == NULL) {
 952                         error = ENOBUFS;
 953                         IPSTAT_INC(ips_odropped);
 954                         goto done;
 955                 }
 956                 /*
 957                  * Make sure the complete packet header gets copied
 958                  * from the originating mbuf to the newly created
 959                  * mbuf. This also ensures that existing firewall
 960                  * classification(s), VLAN tags and so on get copied
 961                  * to the resulting fragmented packet(s):
 962                  */
 963                 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
 964                         m_free(m);
 965                         error = ENOBUFS;
 966                         IPSTAT_INC(ips_odropped);
 967                         goto done;
 968                 }
 969                 /*
 970                  * In the first mbuf, leave room for the link header, then
 971                  * copy the original IP header including options. The payload
 972                  * goes into an additional mbuf chain returned by m_copym().
 973                  */
 974                 m->m_data += max_linkhdr;
 975                 mhip = mtod(m, struct ip *);
 976                 *mhip = *ip;
 977                 if (hlen > sizeof (struct ip)) {
 978                         mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
 979                         mhip->ip_v = IPVERSION;
 980                         mhip->ip_hl = mhlen >> 2;
 981                 }
 982                 m->m_len = mhlen;
 983                 /* XXX do we need to add ip_off below ? */
 984                 mhip->ip_off = ((off - hlen) >> 3) + ip_off;
 985                 if (off + len >= ip_len)
 986                         len = ip_len - off;
 987                 else
 988                         mhip->ip_off |= IP_MF;
 989                 mhip->ip_len = htons((u_short)(len + mhlen));
 990                 m->m_next = m_copym(m0, off, len, M_NOWAIT);
 991                 if (m->m_next == NULL) {        /* copy failed */
 992                         m_free(m);
 993                         error = ENOBUFS;        /* ??? */
 994                         IPSTAT_INC(ips_odropped);
 995                         goto done;
 996                 }
 997                 m->m_pkthdr.len = mhlen + len;
 998 #ifdef MAC
 999                 mac_netinet_fragment(m0, m);
1000 #endif
1001                 mhip->ip_off = htons(mhip->ip_off);
1002                 mhip->ip_sum = 0;
1003                 if (m->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
1004                         mhip->ip_sum = in_cksum(m, mhlen);
1005                         m->m_pkthdr.csum_flags &= ~CSUM_IP;
1006                 }
1007                 *mnext = m;
1008                 mnext = &m->m_nextpkt;
1009         }
1010         IPSTAT_ADD(ips_ofragments, nfrags);
1011
1012         /*
1013          * Update first fragment by trimming what's been copied out
1014          * and updating header.
1015          */
1016         m_adj(m0, hlen + firstlen - ip_len);
1017         m0->m_pkthdr.len = hlen + firstlen;
1018         ip->ip_len = htons((u_short)m0->m_pkthdr.len);
1019         ip->ip_off = htons(ip_off | IP_MF);
1020         ip->ip_sum = 0;
1021         if (m0->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
1022                 ip->ip_sum = in_cksum(m0, hlen);
1023                 m0->m_pkthdr.csum_flags &= ~CSUM_IP;
1024         }
1025
1026 done:
1027         *m_frag = m0;
1028         return error;
1029 }
1030
1031 void
1032 in_delayed_cksum(struct mbuf *m)
1033 {
1034         struct ip *ip;
1035         struct udphdr *uh;
1036         uint16_t cklen, csum, offset;
1037
1038         ip = mtod(m, struct ip *);
1039         offset = ip->ip_hl << 2 ;
1040
1041         if (m->m_pkthdr.csum_flags & CSUM_UDP) {
1042                 /* if udp header is not in the first mbuf copy udplen */
1043                 if (offset + sizeof(struct udphdr) > m->m_len) {
1044                         m_copydata(m, offset + offsetof(struct udphdr,
1045                             uh_ulen), sizeof(cklen), (caddr_t)&cklen);
1046                         cklen = ntohs(cklen);
1047                 } else {
1048                         uh = (struct udphdr *)mtodo(m, offset);
1049                         cklen = ntohs(uh->uh_ulen);
1050                 }
1051                 csum = in_cksum_skip(m, cklen + offset, offset);
1052                 if (csum == 0)
1053                         csum = 0xffff;
1054         } else {
1055                 cklen = ntohs(ip->ip_len);
1056                 csum = in_cksum_skip(m, cklen, offset);
1057         }
1058         offset += m->m_pkthdr.csum_data;        /* checksum offset */
1059
1060         if (offset + sizeof(csum) > m->m_len)
1061                 m_copyback(m, offset, sizeof(csum), (caddr_t)&csum);
1062         else
1063                 *(u_short *)mtodo(m, offset) = csum;
1064 }
1065
1066 /*
1067  * IP socket option processing.
1068  */
1069 int
1070 ip_ctloutput(struct socket *so, struct sockopt *sopt)
1071 {
1072         struct inpcb *inp = sotoinpcb(so);
1073         int     error, optval;
1074 #ifdef  RSS
1075         uint32_t rss_bucket;
1076         int retval;
1077 #endif
1078
1079         error = optval = 0;
1080         if (sopt->sopt_level != IPPROTO_IP) {
1081                 error = EINVAL;
1082
1083                 if (sopt->sopt_level == SOL_SOCKET &&
1084                     sopt->sopt_dir == SOPT_SET) {
1085                         switch (sopt->sopt_name) {
1086                         case SO_REUSEADDR:
1087                                 INP_WLOCK(inp);
1088                                 if ((so->so_options & SO_REUSEADDR) != 0)
1089                                         inp->inp_flags2 |= INP_REUSEADDR;
1090                                 else
1091                                         inp->inp_flags2 &= ~INP_REUSEADDR;
1092                                 INP_WUNLOCK(inp);
1093                                 error = 0;
1094                                 break;
1095                         case SO_REUSEPORT:
1096                                 INP_WLOCK(inp);
1097                                 if ((so->so_options & SO_REUSEPORT) != 0)
1098                                         inp->inp_flags2 |= INP_REUSEPORT;
1099                                 else
1100                                         inp->inp_flags2 &= ~INP_REUSEPORT;
1101                                 INP_WUNLOCK(inp);
1102                                 error = 0;
1103                                 break;
1104                         case SO_REUSEPORT_LB:
1105                                 INP_WLOCK(inp);
1106                                 if ((so->so_options & SO_REUSEPORT_LB) != 0)
1107                                         inp->inp_flags2 |= INP_REUSEPORT_LB;
1108                                 else
1109                                         inp->inp_flags2 &= ~INP_REUSEPORT_LB;
1110                                 INP_WUNLOCK(inp);
1111                                 error = 0;
1112                                 break;
1113                         case SO_SETFIB:
1114                                 INP_WLOCK(inp);
1115                                 inp->inp_inc.inc_fibnum = so->so_fibnum;
1116                                 INP_WUNLOCK(inp);
1117                                 error = 0;
1118                                 break;
1119                         case SO_MAX_PACING_RATE:
1120 #ifdef RATELIMIT
1121                                 INP_WLOCK(inp);
1122                                 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1123                                 INP_WUNLOCK(inp);
1124                                 error = 0;
1125 #else
1126                                 error = EOPNOTSUPP;
1127 #endif
1128                                 break;
1129                         default:
1130                                 break;
1131                         }
1132                 }
1133                 return (error);
1134         }
1135
1136         switch (sopt->sopt_dir) {
1137         case SOPT_SET:
1138                 switch (sopt->sopt_name) {
1139                 case IP_OPTIONS:
1140 #ifdef notyet
1141                 case IP_RETOPTS:
1142 #endif
1143                 {
1144                         struct mbuf *m;
1145                         if (sopt->sopt_valsize > MLEN) {
1146                                 error = EMSGSIZE;
1147                                 break;
1148                         }
1149                         m = m_get(sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
1150                         if (m == NULL) {
1151                                 error = ENOBUFS;
1152                                 break;
1153                         }
1154                         m->m_len = sopt->sopt_valsize;
1155                         error = sooptcopyin(sopt, mtod(m, char *), m->m_len,
1156                                             m->m_len);
1157                         if (error) {
1158                                 m_free(m);
1159                                 break;
1160                         }
1161                         INP_WLOCK(inp);
1162                         error = ip_pcbopts(inp, sopt->sopt_name, m);
1163                         INP_WUNLOCK(inp);
1164                         return (error);
1165                 }
1166
1167                 case IP_BINDANY:
1168                         if (sopt->sopt_td != NULL) {
1169                                 error = priv_check(sopt->sopt_td,
1170                                     PRIV_NETINET_BINDANY);
1171                                 if (error)
1172                                         break;
1173                         }
1174                         /* FALLTHROUGH */
1175                 case IP_BINDMULTI:
1176 #ifdef  RSS
1177                 case IP_RSS_LISTEN_BUCKET:
1178 #endif
1179                 case IP_TOS:
1180                 case IP_TTL:
1181                 case IP_MINTTL:
1182                 case IP_RECVOPTS:
1183                 case IP_RECVRETOPTS:
1184                 case IP_ORIGDSTADDR:
1185                 case IP_RECVDSTADDR:
1186                 case IP_RECVTTL:
1187                 case IP_RECVIF:
1188                 case IP_ONESBCAST:
1189                 case IP_DONTFRAG:
1190                 case IP_RECVTOS:
1191                 case IP_RECVFLOWID:
1192 #ifdef  RSS
1193                 case IP_RECVRSSBUCKETID:
1194 #endif
1195                 case IP_VLAN_PCP:
1196                         error = sooptcopyin(sopt, &optval, sizeof optval,
1197                                             sizeof optval);
1198                         if (error)
1199                                 break;
1200
1201                         switch (sopt->sopt_name) {
1202                         case IP_TOS:
1203                                 inp->inp_ip_tos = optval;
1204                                 break;
1205
1206                         case IP_TTL:
1207                                 inp->inp_ip_ttl = optval;
1208                                 break;
1209
1210                         case IP_MINTTL:
1211                                 if (optval >= 0 && optval <= MAXTTL)
1212                                         inp->inp_ip_minttl = optval;
1213                                 else
1214                                         error = EINVAL;
1215                                 break;
1216
1217 #define OPTSET(bit) do {                                                \
1218         INP_WLOCK(inp);                                                 \
1219         if (optval)                                                     \
1220                 inp->inp_flags |= bit;                                  \
1221         else                                                            \
1222                 inp->inp_flags &= ~bit;                                 \
1223         INP_WUNLOCK(inp);                                               \
1224 } while (0)
1225
1226 #define OPTSET2(bit, val) do {                                          \
1227         INP_WLOCK(inp);                                                 \
1228         if (val)                                                        \
1229                 inp->inp_flags2 |= bit;                                 \
1230         else                                                            \
1231                 inp->inp_flags2 &= ~bit;                                \
1232         INP_WUNLOCK(inp);                                               \
1233 } while (0)
1234
1235                         case IP_RECVOPTS:
1236                                 OPTSET(INP_RECVOPTS);
1237                                 break;
1238
1239                         case IP_RECVRETOPTS:
1240                                 OPTSET(INP_RECVRETOPTS);
1241                                 break;
1242
1243                         case IP_RECVDSTADDR:
1244                                 OPTSET(INP_RECVDSTADDR);
1245                                 break;
1246
1247                         case IP_ORIGDSTADDR:
1248                                 OPTSET2(INP_ORIGDSTADDR, optval);
1249                                 break;
1250
1251                         case IP_RECVTTL:
1252                                 OPTSET(INP_RECVTTL);
1253                                 break;
1254
1255                         case IP_RECVIF:
1256                                 OPTSET(INP_RECVIF);
1257                                 break;
1258
1259                         case IP_ONESBCAST:
1260                                 OPTSET(INP_ONESBCAST);
1261                                 break;
1262                         case IP_DONTFRAG:
1263                                 OPTSET(INP_DONTFRAG);
1264                                 break;
1265                         case IP_BINDANY:
1266                                 OPTSET(INP_BINDANY);
1267                                 break;
1268                         case IP_RECVTOS:
1269                                 OPTSET(INP_RECVTOS);
1270                                 break;
1271                         case IP_BINDMULTI:
1272                                 OPTSET2(INP_BINDMULTI, optval);
1273                                 break;
1274                         case IP_RECVFLOWID:
1275                                 OPTSET2(INP_RECVFLOWID, optval);
1276                                 break;
1277 #ifdef  RSS
1278                         case IP_RSS_LISTEN_BUCKET:
1279                                 if ((optval >= 0) &&
1280                                     (optval < rss_getnumbuckets())) {
1281                                         inp->inp_rss_listen_bucket = optval;
1282                                         OPTSET2(INP_RSS_BUCKET_SET, 1);
1283                                 } else {
1284                                         error = EINVAL;
1285                                 }
1286                                 break;
1287                         case IP_RECVRSSBUCKETID:
1288                                 OPTSET2(INP_RECVRSSBUCKETID, optval);
1289                                 break;
1290 #endif
1291                         case IP_VLAN_PCP:
1292                                 if ((optval >= -1) && (optval <=
1293                                     (INP_2PCP_MASK >> INP_2PCP_SHIFT))) {
1294                                         if (optval == -1) {
1295                                                 INP_WLOCK(inp);
1296                                                 inp->inp_flags2 &=
1297                                                     ~(INP_2PCP_SET |
1298                                                       INP_2PCP_MASK);
1299                                                 INP_WUNLOCK(inp);
1300                                         } else {
1301                                                 INP_WLOCK(inp);
1302                                                 inp->inp_flags2 |=
1303                                                     INP_2PCP_SET;
1304                                                 inp->inp_flags2 &=
1305                                                     ~INP_2PCP_MASK;
1306                                                 inp->inp_flags2 |=
1307                                                     optval << INP_2PCP_SHIFT;
1308                                                 INP_WUNLOCK(inp);
1309                                         }
1310                                 } else
1311                                         error = EINVAL;
1312                                 break;
1313                         }
1314                         break;
1315 #undef OPTSET
1316 #undef OPTSET2
1317
1318                 /*
1319                  * Multicast socket options are processed by the in_mcast
1320                  * module.
1321                  */
1322                 case IP_MULTICAST_IF:
1323                 case IP_MULTICAST_VIF:
1324                 case IP_MULTICAST_TTL:
1325                 case IP_MULTICAST_LOOP:
1326                 case IP_ADD_MEMBERSHIP:
1327                 case IP_DROP_MEMBERSHIP:
1328                 case IP_ADD_SOURCE_MEMBERSHIP:
1329                 case IP_DROP_SOURCE_MEMBERSHIP:
1330                 case IP_BLOCK_SOURCE:
1331                 case IP_UNBLOCK_SOURCE:
1332                 case IP_MSFILTER:
1333                 case MCAST_JOIN_GROUP:
1334                 case MCAST_LEAVE_GROUP:
1335                 case MCAST_JOIN_SOURCE_GROUP:
1336                 case MCAST_LEAVE_SOURCE_GROUP:
1337                 case MCAST_BLOCK_SOURCE:
1338                 case MCAST_UNBLOCK_SOURCE:
1339                         error = inp_setmoptions(inp, sopt);
1340                         break;
1341
1342                 case IP_PORTRANGE:
1343                         error = sooptcopyin(sopt, &optval, sizeof optval,
1344                                             sizeof optval);
1345                         if (error)
1346                                 break;
1347
1348                         INP_WLOCK(inp);
1349                         switch (optval) {
1350                         case IP_PORTRANGE_DEFAULT:
1351                                 inp->inp_flags &= ~(INP_LOWPORT);
1352                                 inp->inp_flags &= ~(INP_HIGHPORT);
1353                                 break;
1354
1355                         case IP_PORTRANGE_HIGH:
1356                                 inp->inp_flags &= ~(INP_LOWPORT);
1357                                 inp->inp_flags |= INP_HIGHPORT;
1358                                 break;
1359
1360                         case IP_PORTRANGE_LOW:
1361                                 inp->inp_flags &= ~(INP_HIGHPORT);
1362                                 inp->inp_flags |= INP_LOWPORT;
1363                                 break;
1364
1365                         default:
1366                                 error = EINVAL;
1367                                 break;
1368                         }
1369                         INP_WUNLOCK(inp);
1370                         break;
1371
1372 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1373                 case IP_IPSEC_POLICY:
1374                         if (IPSEC_ENABLED(ipv4)) {
1375                                 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1376                                 break;
1377                         }
1378                         /* FALLTHROUGH */
1379 #endif /* IPSEC */
1380
1381                 default:
1382                         error = ENOPROTOOPT;
1383                         break;
1384                 }
1385                 break;
1386
1387         case SOPT_GET:
1388                 switch (sopt->sopt_name) {
1389                 case IP_OPTIONS:
1390                 case IP_RETOPTS:
1391                         INP_RLOCK(inp);
1392                         if (inp->inp_options) {
1393                                 struct mbuf *options;
1394
1395                                 options = m_copym(inp->inp_options, 0,
1396                                     M_COPYALL, M_NOWAIT);
1397                                 INP_RUNLOCK(inp);
1398                                 if (options != NULL) {
1399                                         error = sooptcopyout(sopt,
1400                                                              mtod(options, char *),
1401                                                              options->m_len);
1402                                         m_freem(options);
1403                                 } else
1404                                         error = ENOMEM;
1405                         } else {
1406                                 INP_RUNLOCK(inp);
1407                                 sopt->sopt_valsize = 0;
1408                         }
1409                         break;
1410
1411                 case IP_TOS:
1412                 case IP_TTL:
1413                 case IP_MINTTL:
1414                 case IP_RECVOPTS:
1415                 case IP_RECVRETOPTS:
1416                 case IP_ORIGDSTADDR:
1417                 case IP_RECVDSTADDR:
1418                 case IP_RECVTTL:
1419                 case IP_RECVIF:
1420                 case IP_PORTRANGE:
1421                 case IP_ONESBCAST:
1422                 case IP_DONTFRAG:
1423                 case IP_BINDANY:
1424                 case IP_RECVTOS:
1425                 case IP_BINDMULTI:
1426                 case IP_FLOWID:
1427                 case IP_FLOWTYPE:
1428                 case IP_RECVFLOWID:
1429 #ifdef  RSS
1430                 case IP_RSSBUCKETID:
1431                 case IP_RECVRSSBUCKETID:
1432 #endif
1433                 case IP_VLAN_PCP:
1434                         switch (sopt->sopt_name) {
1435                         case IP_TOS:
1436                                 optval = inp->inp_ip_tos;
1437                                 break;
1438
1439                         case IP_TTL:
1440                                 optval = inp->inp_ip_ttl;
1441                                 break;
1442
1443                         case IP_MINTTL:
1444                                 optval = inp->inp_ip_minttl;
1445                                 break;
1446
1447 #define OPTBIT(bit)     (inp->inp_flags & bit ? 1 : 0)
1448 #define OPTBIT2(bit)    (inp->inp_flags2 & bit ? 1 : 0)
1449
1450                         case IP_RECVOPTS:
1451                                 optval = OPTBIT(INP_RECVOPTS);
1452                                 break;
1453
1454                         case IP_RECVRETOPTS:
1455                                 optval = OPTBIT(INP_RECVRETOPTS);
1456                                 break;
1457
1458                         case IP_RECVDSTADDR:
1459                                 optval = OPTBIT(INP_RECVDSTADDR);
1460                                 break;
1461
1462                         case IP_ORIGDSTADDR:
1463                                 optval = OPTBIT2(INP_ORIGDSTADDR);
1464                                 break;
1465
1466                         case IP_RECVTTL:
1467                                 optval = OPTBIT(INP_RECVTTL);
1468                                 break;
1469
1470                         case IP_RECVIF:
1471                                 optval = OPTBIT(INP_RECVIF);
1472                                 break;
1473
1474                         case IP_PORTRANGE:
1475                                 if (inp->inp_flags & INP_HIGHPORT)
1476                                         optval = IP_PORTRANGE_HIGH;
1477                                 else if (inp->inp_flags & INP_LOWPORT)
1478                                         optval = IP_PORTRANGE_LOW;
1479                                 else
1480                                         optval = 0;
1481                                 break;
1482
1483                         case IP_ONESBCAST:
1484                                 optval = OPTBIT(INP_ONESBCAST);
1485                                 break;
1486                         case IP_DONTFRAG:
1487                                 optval = OPTBIT(INP_DONTFRAG);
1488                                 break;
1489                         case IP_BINDANY:
1490                                 optval = OPTBIT(INP_BINDANY);
1491                                 break;
1492                         case IP_RECVTOS:
1493                                 optval = OPTBIT(INP_RECVTOS);
1494                                 break;
1495                         case IP_FLOWID:
1496                                 optval = inp->inp_flowid;
1497                                 break;
1498                         case IP_FLOWTYPE:
1499                                 optval = inp->inp_flowtype;
1500                                 break;
1501                         case IP_RECVFLOWID:
1502                                 optval = OPTBIT2(INP_RECVFLOWID);
1503                                 break;
1504 #ifdef  RSS
1505                         case IP_RSSBUCKETID:
1506                                 retval = rss_hash2bucket(inp->inp_flowid,
1507                                     inp->inp_flowtype,
1508                                     &rss_bucket);
1509                                 if (retval == 0)
1510                                         optval = rss_bucket;
1511                                 else
1512                                         error = EINVAL;
1513                                 break;
1514                         case IP_RECVRSSBUCKETID:
1515                                 optval = OPTBIT2(INP_RECVRSSBUCKETID);
1516                                 break;
1517 #endif
1518                         case IP_BINDMULTI:
1519                                 optval = OPTBIT2(INP_BINDMULTI);
1520                                 break;
1521                         case IP_VLAN_PCP:
1522                                 if (OPTBIT2(INP_2PCP_SET)) {
1523                                         optval = (inp->inp_flags2 &
1524                                             INP_2PCP_MASK) >> INP_2PCP_SHIFT;
1525                                 } else {
1526                                         optval = -1;
1527                                 }
1528                                 break;
1529                         }
1530                         error = sooptcopyout(sopt, &optval, sizeof optval);
1531                         break;
1532
1533                 /*
1534                  * Multicast socket options are processed by the in_mcast
1535                  * module.
1536                  */
1537                 case IP_MULTICAST_IF:
1538                 case IP_MULTICAST_VIF:
1539                 case IP_MULTICAST_TTL:
1540                 case IP_MULTICAST_LOOP:
1541                 case IP_MSFILTER:
1542                         error = inp_getmoptions(inp, sopt);
1543                         break;
1544
1545 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1546                 case IP_IPSEC_POLICY:
1547                         if (IPSEC_ENABLED(ipv4)) {
1548                                 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1549                                 break;
1550                         }
1551                         /* FALLTHROUGH */
1552 #endif /* IPSEC */
1553
1554                 default:
1555                         error = ENOPROTOOPT;
1556                         break;
1557                 }
1558                 break;
1559         }
1560         return (error);
1561 }
1562
1563 /*
1564  * Routine called from ip_output() to loop back a copy of an IP multicast
1565  * packet to the input queue of a specified interface.  Note that this
1566  * calls the output routine of the loopback "driver", but with an interface
1567  * pointer that might NOT be a loopback interface -- evil, but easier than
1568  * replicating that code here.
1569  */
1570 static void
1571 ip_mloopback(struct ifnet *ifp, const struct mbuf *m, int hlen)
1572 {
1573         struct ip *ip;
1574         struct mbuf *copym;
1575
1576         /*
1577          * Make a deep copy of the packet because we're going to
1578          * modify the pack in order to generate checksums.
1579          */
1580         copym = m_dup(m, M_NOWAIT);
1581         if (copym != NULL && (!M_WRITABLE(copym) || copym->m_len < hlen))
1582                 copym = m_pullup(copym, hlen);
1583         if (copym != NULL) {
1584                 /* If needed, compute the checksum and mark it as valid. */
1585                 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
1586                         in_delayed_cksum(copym);
1587                         copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1588                         copym->m_pkthdr.csum_flags |=
1589                             CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1590                         copym->m_pkthdr.csum_data = 0xffff;
1591                 }
1592                 /*
1593                  * We don't bother to fragment if the IP length is greater
1594                  * than the interface's MTU.  Can this possibly matter?
1595                  */
1596                 ip = mtod(copym, struct ip *);
1597                 ip->ip_sum = 0;
1598                 ip->ip_sum = in_cksum(copym, hlen);
1599                 if_simloop(ifp, copym, AF_INET, 0);
1600         }
1601 }