sys/netinet/ip_output.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1982, 1986, 1988, 1990, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      @(#)ip_output.c 8.3 (Berkeley) 1/21/94
  32  */
  33
  34 #include <sys/cdefs.h>
  35 __FBSDID("$FreeBSD$");
  36
  37 #include "opt_inet.h"
  38 #include "opt_ipsec.h"
  39 #include "opt_kern_tls.h"
  40 #include "opt_mbuf_stress_test.h"
  41 #include "opt_mpath.h"
  42 #include "opt_ratelimit.h"
  43 #include "opt_route.h"
  44 #include "opt_rss.h"
  45 #include "opt_sctp.h"
  46
  47 #include <sys/param.h>
  48 #include <sys/systm.h>
  49 #include <sys/kernel.h>
  50 #include <sys/ktls.h>
  51 #include <sys/lock.h>
  52 #include <sys/malloc.h>
  53 #include <sys/mbuf.h>
  54 #include <sys/priv.h>
  55 #include <sys/proc.h>
  56 #include <sys/protosw.h>
  57 #include <sys/rmlock.h>
  58 #include <sys/sdt.h>
  59 #include <sys/socket.h>
  60 #include <sys/socketvar.h>
  61 #include <sys/sysctl.h>
  62 #include <sys/ucred.h>
  63
  64 #include <net/if.h>
  65 #include <net/if_var.h>
  66 #include <net/if_llatbl.h>
  67 #include <net/netisr.h>
  68 #include <net/pfil.h>
  69 #include <net/route.h>
  70 #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
 109 extern int in_mcast_loop;
 110 extern  struct protosw inetsw[];
 111
 112 static inline int
 113 ip_output_pfil(struct mbuf **mp, struct ifnet *ifp, int flags,
 114     struct inpcb *inp, struct sockaddr_in *dst, int *fibnum, int *error)
 115 {
 116         struct m_tag *fwd_tag = NULL;
 117         struct mbuf *m;
 118         struct in_addr odst;
 119         struct ip *ip;
 120         int pflags = PFIL_OUT;
 121
 122         if (flags & IP_FORWARDING)
 123                 pflags |= PFIL_FWD;
 124
 125         m = *mp;
 126         ip = mtod(m, struct ip *);
 127
 128         /* Run through list of hooks for output packets. */
 129         odst.s_addr = ip->ip_dst.s_addr;
 130         switch (pfil_run_hooks(V_inet_pfil_head, mp, ifp, pflags, inp)) {
 131         case PFIL_DROPPED:
 132                 *error = EACCES;
 133                 /* FALLTHROUGH */
 134         case PFIL_CONSUMED:
 135                 return 1; /* Finished */
 136         case PFIL_PASS:
 137                 *error = 0;
 138         }
 139         m = *mp;
 140         ip = mtod(m, struct ip *);
 141
 142         /* See if destination IP address was changed by packet filter. */
 143         if (odst.s_addr != ip->ip_dst.s_addr) {
 144                 m->m_flags |= M_SKIP_FIREWALL;
 145                 /* If destination is now ourself drop to ip_input(). */
 146                 if (in_localip(ip->ip_dst)) {
 147                         m->m_flags |= M_FASTFWD_OURS;
 148                         if (m->m_pkthdr.rcvif == NULL)
 149                                 m->m_pkthdr.rcvif = V_loif;
 150                         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 151                                 m->m_pkthdr.csum_flags |=
 152                                         CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
 153                                 m->m_pkthdr.csum_data = 0xffff;
 154                         }
 155                         m->m_pkthdr.csum_flags |=
 156                                 CSUM_IP_CHECKED | CSUM_IP_VALID;
 157 #if defined(SCTP) || defined(SCTP_SUPPORT)
 158                         if (m->m_pkthdr.csum_flags & CSUM_SCTP)
 159                                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 160 #endif
 161                         *error = netisr_queue(NETISR_IP, m);
 162                         return 1; /* Finished */
 163                 }
 164
 165                 bzero(dst, sizeof(*dst));
 166                 dst->sin_family = AF_INET;
 167                 dst->sin_len = sizeof(*dst);
 168                 dst->sin_addr = ip->ip_dst;
 169
 170                 return -1; /* Reloop */
 171         }
 172         /* See if fib was changed by packet filter. */
 173         if ((*fibnum) != M_GETFIB(m)) {
 174                 m->m_flags |= M_SKIP_FIREWALL;
 175                 *fibnum = M_GETFIB(m);
 176                 return -1; /* Reloop for FIB change */
 177         }
 178
 179         /* See if local, if yes, send it to netisr with IP_FASTFWD_OURS. */
 180         if (m->m_flags & M_FASTFWD_OURS) {
 181                 if (m->m_pkthdr.rcvif == NULL)
 182                         m->m_pkthdr.rcvif = V_loif;
 183                 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 184                         m->m_pkthdr.csum_flags |=
 185                                 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
 186                         m->m_pkthdr.csum_data = 0xffff;
 187                 }
 188 #if defined(SCTP) || defined(SCTP_SUPPORT)
 189                 if (m->m_pkthdr.csum_flags & CSUM_SCTP)
 190                         m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
 191 #endif
 192                 m->m_pkthdr.csum_flags |=
 193                         CSUM_IP_CHECKED | CSUM_IP_VALID;
 194
 195                 *error = netisr_queue(NETISR_IP, m);
 196                 return 1; /* Finished */
 197         }
 198         /* Or forward to some other address? */
 199         if ((m->m_flags & M_IP_NEXTHOP) &&
 200             ((fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL)) {
 201                 bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in));
 202                 m->m_flags |= M_SKIP_FIREWALL;
 203                 m->m_flags &= ~M_IP_NEXTHOP;
 204                 m_tag_delete(m, fwd_tag);
 205
 206                 return -1; /* Reloop for CHANGE of dst */
 207         }
 208
 209         return 0;
 210 }
 211
 212 static int
 213 ip_output_send(struct inpcb *inp, struct ifnet *ifp, struct mbuf *m,
 214     const struct sockaddr_in *gw, struct route *ro, bool stamp_tag)
 215 {
 216 #ifdef KERN_TLS
 217         struct ktls_session *tls = NULL;
 218 #endif
 219         struct m_snd_tag *mst;
 220         int error;
 221
 222         MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0);
 223         mst = NULL;
 224
 225 #ifdef KERN_TLS
 226         /*
 227          * If this is an unencrypted TLS record, save a reference to
 228          * the record.  This local reference is used to call
 229          * ktls_output_eagain after the mbuf has been freed (thus
 230          * dropping the mbuf's reference) in if_output.
 231          */
 232         if (m->m_next != NULL && mbuf_has_tls_session(m->m_next)) {
 233                 tls = ktls_hold(m->m_next->m_epg_tls);
 234                 mst = tls->snd_tag;
 235
 236                 /*
 237                  * If a TLS session doesn't have a valid tag, it must
 238                  * have had an earlier ifp mismatch, so drop this
 239                  * packet.
 240                  */
 241                 if (mst == NULL) {
 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                         error = EAGAIN;
 267                         goto done;
 268                 }
 269
 270                 /* stamp send tag on mbuf */
 271                 m->m_pkthdr.snd_tag = m_snd_tag_ref(mst);
 272                 m->m_pkthdr.csum_flags |= CSUM_SND_TAG;
 273         }
 274
 275         error = (*ifp->if_output)(ifp, m, (const struct sockaddr *)gw, ro);
 276
 277 done:
 278         /* Check for route change invalidating send tags. */
 279 #ifdef KERN_TLS
 280         if (tls != NULL) {
 281                 if (error == EAGAIN)
 282                         error = ktls_output_eagain(inp, tls);
 283                 ktls_free(tls);
 284         }
 285 #endif
 286 #ifdef RATELIMIT
 287         if (error == EAGAIN)
 288                 in_pcboutput_eagain(inp);
 289 #endif
 290         return (error);
 291 }
 292
 293 /* rte<>ro_flags translation */
 294 static inline void
 295 rt_update_ro_flags(struct route *ro)
 296 {
 297         int nh_flags = ro->ro_nh->nh_flags;
 298
 299         ro->ro_flags &= ~ (RT_REJECT|RT_BLACKHOLE|RT_HAS_GW);
 300
 301         ro->ro_flags |= (nh_flags & NHF_REJECT) ? RT_REJECT : 0;
 302         ro->ro_flags |= (nh_flags & NHF_BLACKHOLE) ? RT_BLACKHOLE : 0;
 303         ro->ro_flags |= (nh_flags & NHF_GATEWAY) ? RT_HAS_GW : 0;
 304 }
 305
 306 /*
 307  * IP output.  The packet in mbuf chain m contains a skeletal IP
 308  * header (with len, off, ttl, proto, tos, src, dst).
 309  * The mbuf chain containing the packet will be freed.
 310  * The mbuf opt, if present, will not be freed.
 311  * If route ro is present and has ro_rt initialized, route lookup would be
 312  * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
 313  * then result of route lookup is stored in ro->ro_rt.
 314  *
 315  * In the IP forwarding case, the packet will arrive with options already
 316  * inserted, so must have a NULL opt pointer.
 317  */
 318 int
 319 ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
 320     struct ip_moptions *imo, struct inpcb *inp)
 321 {
 322         struct rm_priotracker in_ifa_tracker;
 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;
 328         int error = 0;
 329         struct sockaddr_in *dst, sin;
 330         const struct sockaddr_in *gw;
 331         struct in_ifaddr *ia;
 332         struct in_addr src;
 333         int isbroadcast;
 334         uint16_t ip_len, ip_off;
 335         uint32_t fibnum;
 336 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 337         int no_route_but_check_spd = 0;
 338 #endif
 339
 340         M_ASSERTPKTHDR(m);
 341         NET_EPOCH_ASSERT();
 342
 343         if (inp != NULL) {
 344                 INP_LOCK_ASSERT(inp);
 345                 M_SETFIB(m, inp->inp_inc.inc_fibnum);
 346                 if ((flags & IP_NODEFAULTFLOWID) == 0) {
 347                         m->m_pkthdr.flowid = inp->inp_flowid;
 348                         M_HASHTYPE_SET(m, inp->inp_flowtype);
 349                 }
 350 #ifdef NUMA
 351                 m->m_pkthdr.numa_domain = inp->inp_numa_domain;
 352 #endif
 353         }
 354
 355         if (opt) {
 356                 int len = 0;
 357                 m = ip_insertoptions(m, opt, &len);
 358                 if (len != 0)
 359                         hlen = len; /* ip->ip_hl is updated above */
 360         }
 361         ip = mtod(m, struct ip *);
 362         ip_len = ntohs(ip->ip_len);
 363         ip_off = ntohs(ip->ip_off);
 364
 365         if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) {
 366                 ip->ip_v = IPVERSION;
 367                 ip->ip_hl = hlen >> 2;
 368                 ip_fillid(ip);
 369         } else {
 370                 /* Header already set, fetch hlen from there */
 371                 hlen = ip->ip_hl << 2;
 372         }
 373         if ((flags & IP_FORWARDING) == 0)
 374                 IPSTAT_INC(ips_localout);
 375
 376         /*
 377          * dst/gw handling:
 378          *
 379          * gw is readonly but can point either to dst OR rt_gateway,
 380          * therefore we need restore gw if we're redoing lookup.
 381          */
 382         fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
 383         if (ro != NULL)
 384                 dst = (struct sockaddr_in *)&ro->ro_dst;
 385         else
 386                 dst = &sin;
 387         if (ro == NULL || ro->ro_nh == NULL) {
 388                 bzero(dst, sizeof(*dst));
 389                 dst->sin_family = AF_INET;
 390                 dst->sin_len = sizeof(*dst);
 391                 dst->sin_addr = ip->ip_dst;
 392         }
 393         gw = dst;
 394 again:
 395         /*
 396          * Validate route against routing table additions;
 397          * a better/more specific route might have been added.
 398          */
 399         if (inp != NULL && ro != NULL && ro->ro_nh != NULL)
 400                 NH_VALIDATE(ro, &inp->inp_rt_cookie, fibnum);
 401         /*
 402          * If there is a cached route,
 403          * check that it is to the same destination
 404          * and is still up.  If not, free it and try again.
 405          * The address family should also be checked in case of sharing the
 406          * cache with IPv6.
 407          * Also check whether routing cache needs invalidation.
 408          */
 409         if (ro != NULL && ro->ro_nh != NULL &&
 410             ((!NH_IS_VALID(ro->ro_nh)) || dst->sin_family != AF_INET ||
 411             dst->sin_addr.s_addr != ip->ip_dst.s_addr))
 412                 RO_INVALIDATE_CACHE(ro);
 413         ia = NULL;
 414         /*
 415          * If routing to interface only, short circuit routing lookup.
 416          * The use of an all-ones broadcast address implies this; an
 417          * interface is specified by the broadcast address of an interface,
 418          * or the destination address of a ptp interface.
 419          */
 420         if (flags & IP_SENDONES) {
 421                 if ((ia = ifatoia(ifa_ifwithbroadaddr(sintosa(dst),
 422                                                       M_GETFIB(m)))) == NULL &&
 423                     (ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
 424                                                     M_GETFIB(m)))) == NULL) {
 425                         IPSTAT_INC(ips_noroute);
 426                         error = ENETUNREACH;
 427                         goto bad;
 428                 }
 429                 ip->ip_dst.s_addr = INADDR_BROADCAST;
 430                 dst->sin_addr = ip->ip_dst;
 431                 ifp = ia->ia_ifp;
 432                 mtu = ifp->if_mtu;
 433                 ip->ip_ttl = 1;
 434                 isbroadcast = 1;
 435                 src = IA_SIN(ia)->sin_addr;
 436         } else if (flags & IP_ROUTETOIF) {
 437                 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
 438                                                     M_GETFIB(m)))) == NULL &&
 439                     (ia = ifatoia(ifa_ifwithnet(sintosa(dst), 0,
 440                                                 M_GETFIB(m)))) == NULL) {
 441                         IPSTAT_INC(ips_noroute);
 442                         error = ENETUNREACH;
 443                         goto bad;
 444                 }
 445                 ifp = ia->ia_ifp;
 446                 mtu = ifp->if_mtu;
 447                 ip->ip_ttl = 1;
 448                 isbroadcast = ifp->if_flags & IFF_BROADCAST ?
 449                     in_ifaddr_broadcast(dst->sin_addr, ia) : 0;
 450                 src = IA_SIN(ia)->sin_addr;
 451         } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
 452             imo != NULL && imo->imo_multicast_ifp != NULL) {
 453                 /*
 454                  * Bypass the normal routing lookup for multicast
 455                  * packets if the interface is specified.
 456                  */
 457                 ifp = imo->imo_multicast_ifp;
 458                 mtu = ifp->if_mtu;
 459                 IFP_TO_IA(ifp, ia, &in_ifa_tracker);
 460                 isbroadcast = 0;        /* fool gcc */
 461                 /* Interface may have no addresses. */
 462                 if (ia != NULL)
 463                         src = IA_SIN(ia)->sin_addr;
 464                 else
 465                         src.s_addr = INADDR_ANY;
 466         } else if (ro != NULL) {
 467                 if (ro->ro_nh == NULL) {
 468                         /*
 469                          * We want to do any cloning requested by the link
 470                          * layer, as this is probably required in all cases
 471                          * for correct operation (as it is for ARP).
 472                          */
 473                         uint32_t flowid;
 474 #ifdef RADIX_MPATH
 475                         flowid = ntohl(ip->ip_src.s_addr ^ ip->ip_dst.s_addr);
 476 #else
 477                         flowid = m->m_pkthdr.flowid;
 478 #endif
 479                         ro->ro_nh = fib4_lookup(fibnum, dst->sin_addr, 0,
 480                             NHR_REF, flowid);
 481
 482                         if (ro->ro_nh == NULL || (!NH_IS_VALID(ro->ro_nh))) {
 483 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 484                                 /*
 485                                  * There is no route for this packet, but it is
 486                                  * possible that a matching SPD entry exists.
 487                                  */
 488                                 no_route_but_check_spd = 1;
 489                                 mtu = 0; /* Silence GCC warning. */
 490                                 goto sendit;
 491 #endif
 492                                 IPSTAT_INC(ips_noroute);
 493                                 error = EHOSTUNREACH;
 494                                 goto bad;
 495                         }
 496                 }
 497                 ia = ifatoia(ro->ro_nh->nh_ifa);
 498                 ifp = ro->ro_nh->nh_ifp;
 499                 counter_u64_add(ro->ro_nh->nh_pksent, 1);
 500                 rt_update_ro_flags(ro);
 501                 if (ro->ro_nh->nh_flags & NHF_GATEWAY)
 502                         gw = &ro->ro_nh->gw4_sa;
 503                 if (ro->ro_nh->nh_flags & NHF_HOST)
 504                         isbroadcast = (ro->ro_nh->nh_flags & NHF_BROADCAST);
 505                 else if (ifp->if_flags & IFF_BROADCAST)
 506                         isbroadcast = in_ifaddr_broadcast(gw->sin_addr, ia);
 507                 else
 508                         isbroadcast = 0;
 509                 if (ro->ro_nh->nh_flags & NHF_HOST)
 510                         mtu = ro->ro_nh->nh_mtu;
 511                 else
 512                         mtu = ifp->if_mtu;
 513                 src = IA_SIN(ia)->sin_addr;
 514         } else {
 515                 struct nhop_object *nh;
 516
 517                 nh = fib4_lookup(M_GETFIB(m), ip->ip_dst, 0, NHR_NONE, 0);
 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                         mtu = 0; /* Silence GCC warning. */
 526                         goto sendit;
 527 #endif
 528                         IPSTAT_INC(ips_noroute);
 529                         error = EHOSTUNREACH;
 530                         goto bad;
 531                 }
 532                 ifp = nh->nh_ifp;
 533                 mtu = nh->nh_mtu;
 534                 /*
 535                  * We are rewriting here dst to be gw actually, contradicting
 536                  * comment at the beginning of the function. However, in this
 537                  * case we are always dealing with on stack dst.
 538                  * In case if pfil(9) sends us back to beginning of the
 539                  * function, the dst would be rewritten by ip_output_pfil().
 540                  */
 541                 MPASS(dst == &sin);
 542                 if (nh->nh_flags & NHF_GATEWAY)
 543                         dst->sin_addr = nh->gw4_sa.sin_addr;
 544                 ia = ifatoia(nh->nh_ifa);
 545                 src = IA_SIN(ia)->sin_addr;
 546                 isbroadcast = (((nh->nh_flags & (NHF_HOST | NHF_BROADCAST)) ==
 547                     (NHF_HOST | NHF_BROADCAST)) ||
 548                     ((ifp->if_flags & IFF_BROADCAST) &&
 549                     in_ifaddr_broadcast(dst->sin_addr, ia)));
 550         }
 551
 552         /* Catch a possible divide by zero later. */
 553         KASSERT(mtu > 0, ("%s: mtu %d <= 0, ro=%p (nh_flags=0x%08x) ifp=%p",
 554             __func__, mtu, ro,
 555             (ro != NULL && ro->ro_nh != NULL) ? ro->ro_nh->nh_flags : 0, ifp));
 556
 557         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
 558                 m->m_flags |= M_MCAST;
 559                 /*
 560                  * IP destination address is multicast.  Make sure "gw"
 561                  * still points to the address in "ro".  (It may have been
 562                  * changed to point to a gateway address, above.)
 563                  */
 564                 gw = dst;
 565                 /*
 566                  * See if the caller provided any multicast options
 567                  */
 568                 if (imo != NULL) {
 569                         ip->ip_ttl = imo->imo_multicast_ttl;
 570                         if (imo->imo_multicast_vif != -1)
 571                                 ip->ip_src.s_addr =
 572                                     ip_mcast_src ?
 573                                     ip_mcast_src(imo->imo_multicast_vif) :
 574                                     INADDR_ANY;
 575                 } else
 576                         ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
 577                 /*
 578                  * Confirm that the outgoing interface supports multicast.
 579                  */
 580                 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
 581                         if ((ifp->if_flags & IFF_MULTICAST) == 0) {
 582                                 IPSTAT_INC(ips_noroute);
 583                                 error = ENETUNREACH;
 584                                 goto bad;
 585                         }
 586                 }
 587                 /*
 588                  * If source address not specified yet, use address
 589                  * of outgoing interface.
 590                  */
 591                 if (ip->ip_src.s_addr == INADDR_ANY)
 592                         ip->ip_src = src;
 593
 594                 if ((imo == NULL && in_mcast_loop) ||
 595                     (imo && imo->imo_multicast_loop)) {
 596                         /*
 597                          * Loop back multicast datagram if not expressly
 598                          * forbidden to do so, even if we are not a member
 599                          * of the group; ip_input() will filter it later,
 600                          * thus deferring a hash lookup and mutex acquisition
 601                          * at the expense of a cheap copy using m_copym().
 602                          */
 603                         ip_mloopback(ifp, m, hlen);
 604                 } else {
 605                         /*
 606                          * If we are acting as a multicast router, perform
 607                          * multicast forwarding as if the packet had just
 608                          * arrived on the interface to which we are about
 609                          * to send.  The multicast forwarding function
 610                          * recursively calls this function, using the
 611                          * IP_FORWARDING flag to prevent infinite recursion.
 612                          *
 613                          * Multicasts that are looped back by ip_mloopback(),
 614                          * above, will be forwarded by the ip_input() routine,
 615                          * if necessary.
 616                          */
 617                         if (V_ip_mrouter && (flags & IP_FORWARDING) == 0) {
 618                                 /*
 619                                  * If rsvp daemon is not running, do not
 620                                  * set ip_moptions. This ensures that the packet
 621                                  * is multicast and not just sent down one link
 622                                  * as prescribed by rsvpd.
 623                                  */
 624                                 if (!V_rsvp_on)
 625                                         imo = NULL;
 626                                 if (ip_mforward &&
 627                                     ip_mforward(ip, ifp, m, imo) != 0) {
 628                                         m_freem(m);
 629                                         goto done;
 630                                 }
 631                         }
 632                 }
 633
 634                 /*
 635                  * Multicasts with a time-to-live of zero may be looped-
 636                  * back, above, but must not be transmitted on a network.
 637                  * Also, multicasts addressed to the loopback interface
 638                  * are not sent -- the above call to ip_mloopback() will
 639                  * loop back a copy. ip_input() will drop the copy if
 640                  * this host does not belong to the destination group on
 641                  * the loopback interface.
 642                  */
 643                 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
 644                         m_freem(m);
 645                         goto done;
 646                 }
 647
 648                 goto sendit;
 649         }
 650
 651         /*
 652          * If the source address is not specified yet, use the address
 653          * of the outoing interface.
 654          */
 655         if (ip->ip_src.s_addr == INADDR_ANY)
 656                 ip->ip_src = src;
 657
 658         /*
 659          * Look for broadcast address and
 660          * verify user is allowed to send
 661          * such a packet.
 662          */
 663         if (isbroadcast) {
 664                 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
 665                         error = EADDRNOTAVAIL;
 666                         goto bad;
 667                 }
 668                 if ((flags & IP_ALLOWBROADCAST) == 0) {
 669                         error = EACCES;
 670                         goto bad;
 671                 }
 672                 /* don't allow broadcast messages to be fragmented */
 673                 if (ip_len > mtu) {
 674                         error = EMSGSIZE;
 675                         goto bad;
 676                 }
 677                 m->m_flags |= M_BCAST;
 678         } else {
 679                 m->m_flags &= ~M_BCAST;
 680         }
 681
 682 sendit:
 683 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 684         if (IPSEC_ENABLED(ipv4)) {
 685                 if ((error = IPSEC_OUTPUT(ipv4, m, inp)) != 0) {
 686                         if (error == EINPROGRESS)
 687                                 error = 0;
 688                         goto done;
 689                 }
 690         }
 691         /*
 692          * Check if there was a route for this packet; return error if not.
 693          */
 694         if (no_route_but_check_spd) {
 695                 IPSTAT_INC(ips_noroute);
 696                 error = EHOSTUNREACH;
 697                 goto bad;
 698         }
 699         /* Update variables that are affected by ipsec4_output(). */
 700         ip = mtod(m, struct ip *);
 701         hlen = ip->ip_hl << 2;
 702 #endif /* IPSEC */
 703
 704         /* Jump over all PFIL processing if hooks are not active. */
 705         if (PFIL_HOOKED_OUT(V_inet_pfil_head)) {
 706                 switch (ip_output_pfil(&m, ifp, flags, inp, dst, &fibnum,
 707                     &error)) {
 708                 case 1: /* Finished */
 709                         goto done;
 710
 711                 case 0: /* Continue normally */
 712                         ip = mtod(m, struct ip *);
 713                         break;
 714
 715                 case -1: /* Need to try again */
 716                         /* Reset everything for a new round */
 717                         if (ro != NULL) {
 718                                 RO_NHFREE(ro);
 719                                 ro->ro_prepend = NULL;
 720                         }
 721                         gw = dst;
 722                         ip = mtod(m, struct ip *);
 723                         goto again;
 724
 725                 }
 726         }
 727
 728         /* IN_LOOPBACK must not appear on the wire - RFC1122. */
 729         if (IN_LOOPBACK(ntohl(ip->ip_dst.s_addr)) ||
 730             IN_LOOPBACK(ntohl(ip->ip_src.s_addr))) {
 731                 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
 732                         IPSTAT_INC(ips_badaddr);
 733                         error = EADDRNOTAVAIL;
 734                         goto bad;
 735                 }
 736         }
 737
 738         m->m_pkthdr.csum_flags |= CSUM_IP;
 739         if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
 740                 m = mb_unmapped_to_ext(m);
 741                 if (m == NULL) {
 742                         IPSTAT_INC(ips_odropped);
 743                         error = ENOBUFS;
 744                         goto bad;
 745                 }
 746                 in_delayed_cksum(m);
 747                 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
 748         } else if ((ifp->if_capenable & IFCAP_NOMAP) == 0) {
 749                 m = mb_unmapped_to_ext(m);
 750                 if (m == NULL) {
 751                         IPSTAT_INC(ips_odropped);
 752                         error = ENOBUFS;
 753                         goto bad;
 754                 }
 755         }
 756 #if defined(SCTP) || defined(SCTP_SUPPORT)
 757         if (m->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
 758                 m = mb_unmapped_to_ext(m);
 759                 if (m == NULL) {
 760                         IPSTAT_INC(ips_odropped);
 761                         error = ENOBUFS;
 762                         goto bad;
 763                 }
 764                 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
 765                 m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
 766         }
 767 #endif
 768
 769         /*
 770          * If small enough for interface, or the interface will take
 771          * care of the fragmentation for us, we can just send directly.
 772          */
 773         if (ip_len <= mtu ||
 774             (m->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0) {
 775                 ip->ip_sum = 0;
 776                 if (m->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
 777                         ip->ip_sum = in_cksum(m, hlen);
 778                         m->m_pkthdr.csum_flags &= ~CSUM_IP;
 779                 }
 780
 781                 /*
 782                  * Record statistics for this interface address.
 783                  * With CSUM_TSO the byte/packet count will be slightly
 784                  * incorrect because we count the IP+TCP headers only
 785                  * once instead of for every generated packet.
 786                  */
 787                 if (!(flags & IP_FORWARDING) && ia) {
 788                         if (m->m_pkthdr.csum_flags & CSUM_TSO)
 789                                 counter_u64_add(ia->ia_ifa.ifa_opackets,
 790                                     m->m_pkthdr.len / m->m_pkthdr.tso_segsz);
 791                         else
 792                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
 793
 794                         counter_u64_add(ia->ia_ifa.ifa_obytes, m->m_pkthdr.len);
 795                 }
 796 #ifdef MBUF_STRESS_TEST
 797                 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size)
 798                         m = m_fragment(m, M_NOWAIT, mbuf_frag_size);
 799 #endif
 800                 /*
 801                  * Reset layer specific mbuf flags
 802                  * to avoid confusing lower layers.
 803                  */
 804                 m_clrprotoflags(m);
 805                 IP_PROBE(send, NULL, NULL, ip, ifp, ip, NULL);
 806                 error = ip_output_send(inp, ifp, m, gw, ro,
 807                     (flags & IP_NO_SND_TAG_RL) ? false : true);
 808                 goto done;
 809         }
 810
 811         /* Balk when DF bit is set or the interface didn't support TSO. */
 812         if ((ip_off & IP_DF) || (m->m_pkthdr.csum_flags & CSUM_TSO)) {
 813                 error = EMSGSIZE;
 814                 IPSTAT_INC(ips_cantfrag);
 815                 goto bad;
 816         }
 817
 818         /*
 819          * Too large for interface; fragment if possible. If successful,
 820          * on return, m will point to a list of packets to be sent.
 821          */
 822         error = ip_fragment(ip, &m, mtu, ifp->if_hwassist);
 823         if (error)
 824                 goto bad;
 825         for (; m; m = m0) {
 826                 m0 = m->m_nextpkt;
 827                 m->m_nextpkt = 0;
 828                 if (error == 0) {
 829                         /* Record statistics for this interface address. */
 830                         if (ia != NULL) {
 831                                 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
 832                                 counter_u64_add(ia->ia_ifa.ifa_obytes,
 833                                     m->m_pkthdr.len);
 834                         }
 835                         /*
 836                          * Reset layer specific mbuf flags
 837                          * to avoid confusing upper layers.
 838                          */
 839                         m_clrprotoflags(m);
 840
 841                         IP_PROBE(send, NULL, NULL, mtod(m, struct ip *), ifp,
 842                             mtod(m, struct ip *), NULL);
 843                         error = ip_output_send(inp, ifp, m, gw, ro, true);
 844                 } else
 845                         m_freem(m);
 846         }
 847
 848         if (error == 0)
 849                 IPSTAT_INC(ips_fragmented);
 850
 851 done:
 852         return (error);
 853  bad:
 854         m_freem(m);
 855         goto done;
 856 }
 857
 858 /*
 859  * Create a chain of fragments which fit the given mtu. m_frag points to the
 860  * mbuf to be fragmented; on return it points to the chain with the fragments.
 861  * Return 0 if no error. If error, m_frag may contain a partially built
 862  * chain of fragments that should be freed by the caller.
 863  *
 864  * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
 865  */
 866 int
 867 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
 868     u_long if_hwassist_flags)
 869 {
 870         int error = 0;
 871         int hlen = ip->ip_hl << 2;
 872         int len = (mtu - hlen) & ~7;    /* size of payload in each fragment */
 873         int off;
 874         struct mbuf *m0 = *m_frag;      /* the original packet          */
 875         int firstlen;
 876         struct mbuf **mnext;
 877         int nfrags;
 878         uint16_t ip_len, ip_off;
 879
 880         ip_len = ntohs(ip->ip_len);
 881         ip_off = ntohs(ip->ip_off);
 882
 883         if (ip_off & IP_DF) {   /* Fragmentation not allowed */
 884                 IPSTAT_INC(ips_cantfrag);
 885                 return EMSGSIZE;
 886         }
 887
 888         /*
 889          * Must be able to put at least 8 bytes per fragment.
 890          */
 891         if (len < 8)
 892                 return EMSGSIZE;
 893
 894         /*
 895          * If the interface will not calculate checksums on
 896          * fragmented packets, then do it here.
 897          */
 898         if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
 899                 m0 = mb_unmapped_to_ext(m0);
 900                 if (m0 == NULL) {
 901                         error = ENOBUFS;
 902                         IPSTAT_INC(ips_odropped);
 903                         goto done;
 904                 }
 905                 in_delayed_cksum(m0);
 906                 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
 907         }
 908 #if defined(SCTP) || defined(SCTP_SUPPORT)
 909         if (m0->m_pkthdr.csum_flags & CSUM_SCTP) {
 910                 m0 = mb_unmapped_to_ext(m0);
 911                 if (m0 == NULL) {
 912                         error = ENOBUFS;
 913                         IPSTAT_INC(ips_odropped);
 914                         goto done;
 915                 }
 916                 sctp_delayed_cksum(m0, hlen);
 917                 m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
 918         }
 919 #endif
 920         if (len > PAGE_SIZE) {
 921                 /*
 922                  * Fragment large datagrams such that each segment
 923                  * contains a multiple of PAGE_SIZE amount of data,
 924                  * plus headers. This enables a receiver to perform
 925                  * page-flipping zero-copy optimizations.
 926                  *
 927                  * XXX When does this help given that sender and receiver
 928                  * could have different page sizes, and also mtu could
 929                  * be less than the receiver's page size ?
 930                  */
 931                 int newlen;
 932
 933                 off = MIN(mtu, m0->m_pkthdr.len);
 934
 935                 /*
 936                  * firstlen (off - hlen) must be aligned on an
 937                  * 8-byte boundary
 938                  */
 939                 if (off < hlen)
 940                         goto smart_frag_failure;
 941                 off = ((off - hlen) & ~7) + hlen;
 942                 newlen = (~PAGE_MASK) & mtu;
 943                 if ((newlen + sizeof (struct ip)) > mtu) {
 944                         /* we failed, go back the default */
 945 smart_frag_failure:
 946                         newlen = len;
 947                         off = hlen + len;
 948                 }
 949                 len = newlen;
 950
 951         } else {
 952                 off = hlen + len;
 953         }
 954
 955         firstlen = off - hlen;
 956         mnext = &m0->m_nextpkt;         /* pointer to next packet */
 957
 958         /*
 959          * Loop through length of segment after first fragment,
 960          * make new header and copy data of each part and link onto chain.
 961          * Here, m0 is the original packet, m is the fragment being created.
 962          * The fragments are linked off the m_nextpkt of the original
 963          * packet, which after processing serves as the first fragment.
 964          */
 965         for (nfrags = 1; off < ip_len; off += len, nfrags++) {
 966                 struct ip *mhip;        /* ip header on the fragment */
 967                 struct mbuf *m;
 968                 int mhlen = sizeof (struct ip);
 969
 970                 m = m_gethdr(M_NOWAIT, MT_DATA);
 971                 if (m == NULL) {
 972                         error = ENOBUFS;
 973                         IPSTAT_INC(ips_odropped);
 974                         goto done;
 975                 }
 976                 /*
 977                  * Make sure the complete packet header gets copied
 978                  * from the originating mbuf to the newly created
 979                  * mbuf. This also ensures that existing firewall
 980                  * classification(s), VLAN tags and so on get copied
 981                  * to the resulting fragmented packet(s):
 982                  */
 983                 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
 984                         m_free(m);
 985                         error = ENOBUFS;
 986                         IPSTAT_INC(ips_odropped);
 987                         goto done;
 988                 }
 989                 /*
 990                  * In the first mbuf, leave room for the link header, then
 991                  * copy the original IP header including options. The payload
 992                  * goes into an additional mbuf chain returned by m_copym().
 993                  */
 994                 m->m_data += max_linkhdr;
 995                 mhip = mtod(m, struct ip *);
 996                 *mhip = *ip;
 997                 if (hlen > sizeof (struct ip)) {
 998                         mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
 999                         mhip->ip_v = IPVERSION;
1000                         mhip->ip_hl = mhlen >> 2;
1001                 }
1002                 m->m_len = mhlen;
1003                 /* XXX do we need to add ip_off below ? */
1004                 mhip->ip_off = ((off - hlen) >> 3) + ip_off;
1005                 if (off + len >= ip_len)
1006                         len = ip_len - off;
1007                 else
1008                         mhip->ip_off |= IP_MF;
1009                 mhip->ip_len = htons((u_short)(len + mhlen));
1010                 m->m_next = m_copym(m0, off, len, M_NOWAIT);
1011                 if (m->m_next == NULL) {        /* copy failed */
1012                         m_free(m);
1013                         error = ENOBUFS;        /* ??? */
1014                         IPSTAT_INC(ips_odropped);
1015                         goto done;
1016                 }
1017                 m->m_pkthdr.len = mhlen + len;
1018 #ifdef MAC
1019                 mac_netinet_fragment(m0, m);
1020 #endif
1021                 mhip->ip_off = htons(mhip->ip_off);
1022                 mhip->ip_sum = 0;
1023                 if (m->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
1024                         mhip->ip_sum = in_cksum(m, mhlen);
1025                         m->m_pkthdr.csum_flags &= ~CSUM_IP;
1026                 }
1027                 *mnext = m;
1028                 mnext = &m->m_nextpkt;
1029         }
1030         IPSTAT_ADD(ips_ofragments, nfrags);
1031
1032         /*
1033          * Update first fragment by trimming what's been copied out
1034          * and updating header.
1035          */
1036         m_adj(m0, hlen + firstlen - ip_len);
1037         m0->m_pkthdr.len = hlen + firstlen;
1038         ip->ip_len = htons((u_short)m0->m_pkthdr.len);
1039         ip->ip_off = htons(ip_off | IP_MF);
1040         ip->ip_sum = 0;
1041         if (m0->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
1042                 ip->ip_sum = in_cksum(m0, hlen);
1043                 m0->m_pkthdr.csum_flags &= ~CSUM_IP;
1044         }
1045
1046 done:
1047         *m_frag = m0;
1048         return error;
1049 }
1050
1051 void
1052 in_delayed_cksum(struct mbuf *m)
1053 {
1054         struct ip *ip;
1055         struct udphdr *uh;
1056         uint16_t cklen, csum, offset;
1057
1058         ip = mtod(m, struct ip *);
1059         offset = ip->ip_hl << 2 ;
1060
1061         if (m->m_pkthdr.csum_flags & CSUM_UDP) {
1062                 /* if udp header is not in the first mbuf copy udplen */
1063                 if (offset + sizeof(struct udphdr) > m->m_len) {
1064                         m_copydata(m, offset + offsetof(struct udphdr,
1065                             uh_ulen), sizeof(cklen), (caddr_t)&cklen);
1066                         cklen = ntohs(cklen);
1067                 } else {
1068                         uh = (struct udphdr *)mtodo(m, offset);
1069                         cklen = ntohs(uh->uh_ulen);
1070                 }
1071                 csum = in_cksum_skip(m, cklen + offset, offset);
1072                 if (csum == 0)
1073                         csum = 0xffff;
1074         } else {
1075                 cklen = ntohs(ip->ip_len);
1076                 csum = in_cksum_skip(m, cklen, offset);
1077         }
1078         offset += m->m_pkthdr.csum_data;        /* checksum offset */
1079
1080         if (offset + sizeof(csum) > m->m_len)
1081                 m_copyback(m, offset, sizeof(csum), (caddr_t)&csum);
1082         else
1083                 *(u_short *)mtodo(m, offset) = csum;
1084 }
1085
1086 /*
1087  * IP socket option processing.
1088  */
1089 int
1090 ip_ctloutput(struct socket *so, struct sockopt *sopt)
1091 {
1092         struct inpcb *inp = sotoinpcb(so);
1093         int     error, optval;
1094 #ifdef  RSS
1095         uint32_t rss_bucket;
1096         int retval;
1097 #endif
1098
1099         error = optval = 0;
1100         if (sopt->sopt_level != IPPROTO_IP) {
1101                 error = EINVAL;
1102
1103                 if (sopt->sopt_level == SOL_SOCKET &&
1104                     sopt->sopt_dir == SOPT_SET) {
1105                         switch (sopt->sopt_name) {
1106                         case SO_REUSEADDR:
1107                                 INP_WLOCK(inp);
1108                                 if ((so->so_options & SO_REUSEADDR) != 0)
1109                                         inp->inp_flags2 |= INP_REUSEADDR;
1110                                 else
1111                                         inp->inp_flags2 &= ~INP_REUSEADDR;
1112                                 INP_WUNLOCK(inp);
1113                                 error = 0;
1114                                 break;
1115                         case SO_REUSEPORT:
1116                                 INP_WLOCK(inp);
1117                                 if ((so->so_options & SO_REUSEPORT) != 0)
1118                                         inp->inp_flags2 |= INP_REUSEPORT;
1119                                 else
1120                                         inp->inp_flags2 &= ~INP_REUSEPORT;
1121                                 INP_WUNLOCK(inp);
1122                                 error = 0;
1123                                 break;
1124                         case SO_REUSEPORT_LB:
1125                                 INP_WLOCK(inp);
1126                                 if ((so->so_options & SO_REUSEPORT_LB) != 0)
1127                                         inp->inp_flags2 |= INP_REUSEPORT_LB;
1128                                 else
1129                                         inp->inp_flags2 &= ~INP_REUSEPORT_LB;
1130                                 INP_WUNLOCK(inp);
1131                                 error = 0;
1132                                 break;
1133                         case SO_SETFIB:
1134                                 INP_WLOCK(inp);
1135                                 inp->inp_inc.inc_fibnum = so->so_fibnum;
1136                                 INP_WUNLOCK(inp);
1137                                 error = 0;
1138                                 break;
1139                         case SO_MAX_PACING_RATE:
1140 #ifdef RATELIMIT
1141                                 INP_WLOCK(inp);
1142                                 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1143                                 INP_WUNLOCK(inp);
1144                                 error = 0;
1145 #else
1146                                 error = EOPNOTSUPP;
1147 #endif
1148                                 break;
1149                         default:
1150                                 break;
1151                         }
1152                 }
1153                 return (error);
1154         }
1155
1156         switch (sopt->sopt_dir) {
1157         case SOPT_SET:
1158                 switch (sopt->sopt_name) {
1159                 case IP_OPTIONS:
1160 #ifdef notyet
1161                 case IP_RETOPTS:
1162 #endif
1163                 {
1164                         struct mbuf *m;
1165                         if (sopt->sopt_valsize > MLEN) {
1166                                 error = EMSGSIZE;
1167                                 break;
1168                         }
1169                         m = m_get(sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
1170                         if (m == NULL) {
1171                                 error = ENOBUFS;
1172                                 break;
1173                         }
1174                         m->m_len = sopt->sopt_valsize;
1175                         error = sooptcopyin(sopt, mtod(m, char *), m->m_len,
1176                                             m->m_len);
1177                         if (error) {
1178                                 m_free(m);
1179                                 break;
1180                         }
1181                         INP_WLOCK(inp);
1182                         error = ip_pcbopts(inp, sopt->sopt_name, m);
1183                         INP_WUNLOCK(inp);
1184                         return (error);
1185                 }
1186
1187                 case IP_BINDANY:
1188                         if (sopt->sopt_td != NULL) {
1189                                 error = priv_check(sopt->sopt_td,
1190                                     PRIV_NETINET_BINDANY);
1191                                 if (error)
1192                                         break;
1193                         }
1194                         /* FALLTHROUGH */
1195                 case IP_BINDMULTI:
1196 #ifdef  RSS
1197                 case IP_RSS_LISTEN_BUCKET:
1198 #endif
1199                 case IP_TOS:
1200                 case IP_TTL:
1201                 case IP_MINTTL:
1202                 case IP_RECVOPTS:
1203                 case IP_RECVRETOPTS:
1204                 case IP_ORIGDSTADDR:
1205                 case IP_RECVDSTADDR:
1206                 case IP_RECVTTL:
1207                 case IP_RECVIF:
1208                 case IP_ONESBCAST:
1209                 case IP_DONTFRAG:
1210                 case IP_RECVTOS:
1211                 case IP_RECVFLOWID:
1212 #ifdef  RSS
1213                 case IP_RECVRSSBUCKETID:
1214 #endif
1215                         error = sooptcopyin(sopt, &optval, sizeof optval,
1216                                             sizeof optval);
1217                         if (error)
1218                                 break;
1219
1220                         switch (sopt->sopt_name) {
1221                         case IP_TOS:
1222                                 inp->inp_ip_tos = optval;
1223                                 break;
1224
1225                         case IP_TTL:
1226                                 inp->inp_ip_ttl = optval;
1227                                 break;
1228
1229                         case IP_MINTTL:
1230                                 if (optval >= 0 && optval <= MAXTTL)
1231                                         inp->inp_ip_minttl = optval;
1232                                 else
1233                                         error = EINVAL;
1234                                 break;
1235
1236 #define OPTSET(bit) do {                                                \
1237         INP_WLOCK(inp);                                                 \
1238         if (optval)                                                     \
1239                 inp->inp_flags |= bit;                                  \
1240         else                                                            \
1241                 inp->inp_flags &= ~bit;                                 \
1242         INP_WUNLOCK(inp);                                               \
1243 } while (0)
1244
1245 #define OPTSET2(bit, val) do {                                          \
1246         INP_WLOCK(inp);                                                 \
1247         if (val)                                                        \
1248                 inp->inp_flags2 |= bit;                                 \
1249         else                                                            \
1250                 inp->inp_flags2 &= ~bit;                                \
1251         INP_WUNLOCK(inp);                                               \
1252 } while (0)
1253
1254                         case IP_RECVOPTS:
1255                                 OPTSET(INP_RECVOPTS);
1256                                 break;
1257
1258                         case IP_RECVRETOPTS:
1259                                 OPTSET(INP_RECVRETOPTS);
1260                                 break;
1261
1262                         case IP_RECVDSTADDR:
1263                                 OPTSET(INP_RECVDSTADDR);
1264                                 break;
1265
1266                         case IP_ORIGDSTADDR:
1267                                 OPTSET2(INP_ORIGDSTADDR, optval);
1268                                 break;
1269
1270                         case IP_RECVTTL:
1271                                 OPTSET(INP_RECVTTL);
1272                                 break;
1273
1274                         case IP_RECVIF:
1275                                 OPTSET(INP_RECVIF);
1276                                 break;
1277
1278                         case IP_ONESBCAST:
1279                                 OPTSET(INP_ONESBCAST);
1280                                 break;
1281                         case IP_DONTFRAG:
1282                                 OPTSET(INP_DONTFRAG);
1283                                 break;
1284                         case IP_BINDANY:
1285                                 OPTSET(INP_BINDANY);
1286                                 break;
1287                         case IP_RECVTOS:
1288                                 OPTSET(INP_RECVTOS);
1289                                 break;
1290                         case IP_BINDMULTI:
1291                                 OPTSET2(INP_BINDMULTI, optval);
1292                                 break;
1293                         case IP_RECVFLOWID:
1294                                 OPTSET2(INP_RECVFLOWID, optval);
1295                                 break;
1296 #ifdef  RSS
1297                         case IP_RSS_LISTEN_BUCKET:
1298                                 if ((optval >= 0) &&
1299                                     (optval < rss_getnumbuckets())) {
1300                                         inp->inp_rss_listen_bucket = optval;
1301                                         OPTSET2(INP_RSS_BUCKET_SET, 1);
1302                                 } else {
1303                                         error = EINVAL;
1304                                 }
1305                                 break;
1306                         case IP_RECVRSSBUCKETID:
1307                                 OPTSET2(INP_RECVRSSBUCKETID, optval);
1308                                 break;
1309 #endif
1310                         }
1311                         break;
1312 #undef OPTSET
1313 #undef OPTSET2
1314
1315                 /*
1316                  * Multicast socket options are processed by the in_mcast
1317                  * module.
1318                  */
1319                 case IP_MULTICAST_IF:
1320                 case IP_MULTICAST_VIF:
1321                 case IP_MULTICAST_TTL:
1322                 case IP_MULTICAST_LOOP:
1323                 case IP_ADD_MEMBERSHIP:
1324                 case IP_DROP_MEMBERSHIP:
1325                 case IP_ADD_SOURCE_MEMBERSHIP:
1326                 case IP_DROP_SOURCE_MEMBERSHIP:
1327                 case IP_BLOCK_SOURCE:
1328                 case IP_UNBLOCK_SOURCE:
1329                 case IP_MSFILTER:
1330                 case MCAST_JOIN_GROUP:
1331                 case MCAST_LEAVE_GROUP:
1332                 case MCAST_JOIN_SOURCE_GROUP:
1333                 case MCAST_LEAVE_SOURCE_GROUP:
1334                 case MCAST_BLOCK_SOURCE:
1335                 case MCAST_UNBLOCK_SOURCE:
1336                         error = inp_setmoptions(inp, sopt);
1337                         break;
1338
1339                 case IP_PORTRANGE:
1340                         error = sooptcopyin(sopt, &optval, sizeof optval,
1341                                             sizeof optval);
1342                         if (error)
1343                                 break;
1344
1345                         INP_WLOCK(inp);
1346                         switch (optval) {
1347                         case IP_PORTRANGE_DEFAULT:
1348                                 inp->inp_flags &= ~(INP_LOWPORT);
1349                                 inp->inp_flags &= ~(INP_HIGHPORT);
1350                                 break;
1351
1352                         case IP_PORTRANGE_HIGH:
1353                                 inp->inp_flags &= ~(INP_LOWPORT);
1354                                 inp->inp_flags |= INP_HIGHPORT;
1355                                 break;
1356
1357                         case IP_PORTRANGE_LOW:
1358                                 inp->inp_flags &= ~(INP_HIGHPORT);
1359                                 inp->inp_flags |= INP_LOWPORT;
1360                                 break;
1361
1362                         default:
1363                                 error = EINVAL;
1364                                 break;
1365                         }
1366                         INP_WUNLOCK(inp);
1367                         break;
1368
1369 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1370                 case IP_IPSEC_POLICY:
1371                         if (IPSEC_ENABLED(ipv4)) {
1372                                 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1373                                 break;
1374                         }
1375                         /* FALLTHROUGH */
1376 #endif /* IPSEC */
1377
1378                 default:
1379                         error = ENOPROTOOPT;
1380                         break;
1381                 }
1382                 break;
1383
1384         case SOPT_GET:
1385                 switch (sopt->sopt_name) {
1386                 case IP_OPTIONS:
1387                 case IP_RETOPTS:
1388                         INP_RLOCK(inp);
1389                         if (inp->inp_options) {
1390                                 struct mbuf *options;
1391
1392                                 options = m_copym(inp->inp_options, 0,
1393                                     M_COPYALL, M_NOWAIT);
1394                                 INP_RUNLOCK(inp);
1395                                 if (options != NULL) {
1396                                         error = sooptcopyout(sopt,
1397                                                              mtod(options, char *),
1398                                                              options->m_len);
1399                                         m_freem(options);
1400                                 } else
1401                                         error = ENOMEM;
1402                         } else {
1403                                 INP_RUNLOCK(inp);
1404                                 sopt->sopt_valsize = 0;
1405                         }
1406                         break;
1407
1408                 case IP_TOS:
1409                 case IP_TTL:
1410                 case IP_MINTTL:
1411                 case IP_RECVOPTS:
1412                 case IP_RECVRETOPTS:
1413                 case IP_ORIGDSTADDR:
1414                 case IP_RECVDSTADDR:
1415                 case IP_RECVTTL:
1416                 case IP_RECVIF:
1417                 case IP_PORTRANGE:
1418                 case IP_ONESBCAST:
1419                 case IP_DONTFRAG:
1420                 case IP_BINDANY:
1421                 case IP_RECVTOS:
1422                 case IP_BINDMULTI:
1423                 case IP_FLOWID:
1424                 case IP_FLOWTYPE:
1425                 case IP_RECVFLOWID:
1426 #ifdef  RSS
1427                 case IP_RSSBUCKETID:
1428                 case IP_RECVRSSBUCKETID:
1429 #endif
1430                         switch (sopt->sopt_name) {
1431
1432                         case IP_TOS:
1433                                 optval = inp->inp_ip_tos;
1434                                 break;
1435
1436                         case IP_TTL:
1437                                 optval = inp->inp_ip_ttl;
1438                                 break;
1439
1440                         case IP_MINTTL:
1441                                 optval = inp->inp_ip_minttl;
1442                                 break;
1443
1444 #define OPTBIT(bit)     (inp->inp_flags & bit ? 1 : 0)
1445 #define OPTBIT2(bit)    (inp->inp_flags2 & bit ? 1 : 0)
1446
1447                         case IP_RECVOPTS:
1448                                 optval = OPTBIT(INP_RECVOPTS);
1449                                 break;
1450
1451                         case IP_RECVRETOPTS:
1452                                 optval = OPTBIT(INP_RECVRETOPTS);
1453                                 break;
1454
1455                         case IP_RECVDSTADDR:
1456                                 optval = OPTBIT(INP_RECVDSTADDR);
1457                                 break;
1458
1459                         case IP_ORIGDSTADDR:
1460                                 optval = OPTBIT2(INP_ORIGDSTADDR);
1461                                 break;
1462
1463                         case IP_RECVTTL:
1464                                 optval = OPTBIT(INP_RECVTTL);
1465                                 break;
1466
1467                         case IP_RECVIF:
1468                                 optval = OPTBIT(INP_RECVIF);
1469                                 break;
1470
1471                         case IP_PORTRANGE:
1472                                 if (inp->inp_flags & INP_HIGHPORT)
1473                                         optval = IP_PORTRANGE_HIGH;
1474                                 else if (inp->inp_flags & INP_LOWPORT)
1475                                         optval = IP_PORTRANGE_LOW;
1476                                 else
1477                                         optval = 0;
1478                                 break;
1479
1480                         case IP_ONESBCAST:
1481                                 optval = OPTBIT(INP_ONESBCAST);
1482                                 break;
1483                         case IP_DONTFRAG:
1484                                 optval = OPTBIT(INP_DONTFRAG);
1485                                 break;
1486                         case IP_BINDANY:
1487                                 optval = OPTBIT(INP_BINDANY);
1488                                 break;
1489                         case IP_RECVTOS:
1490                                 optval = OPTBIT(INP_RECVTOS);
1491                                 break;
1492                         case IP_FLOWID:
1493                                 optval = inp->inp_flowid;
1494                                 break;
1495                         case IP_FLOWTYPE:
1496                                 optval = inp->inp_flowtype;
1497                                 break;
1498                         case IP_RECVFLOWID:
1499                                 optval = OPTBIT2(INP_RECVFLOWID);
1500                                 break;
1501 #ifdef  RSS
1502                         case IP_RSSBUCKETID:
1503                                 retval = rss_hash2bucket(inp->inp_flowid,
1504                                     inp->inp_flowtype,
1505                                     &rss_bucket);
1506                                 if (retval == 0)
1507                                         optval = rss_bucket;
1508                                 else
1509                                         error = EINVAL;
1510                                 break;
1511                         case IP_RECVRSSBUCKETID:
1512                                 optval = OPTBIT2(INP_RECVRSSBUCKETID);
1513                                 break;
1514 #endif
1515                         case IP_BINDMULTI:
1516                                 optval = OPTBIT2(INP_BINDMULTI);
1517                                 break;
1518                         }
1519                         error = sooptcopyout(sopt, &optval, sizeof optval);
1520                         break;
1521
1522                 /*
1523                  * Multicast socket options are processed by the in_mcast
1524                  * module.
1525                  */
1526                 case IP_MULTICAST_IF:
1527                 case IP_MULTICAST_VIF:
1528                 case IP_MULTICAST_TTL:
1529                 case IP_MULTICAST_LOOP:
1530                 case IP_MSFILTER:
1531                         error = inp_getmoptions(inp, sopt);
1532                         break;
1533
1534 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1535                 case IP_IPSEC_POLICY:
1536                         if (IPSEC_ENABLED(ipv4)) {
1537                                 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1538                                 break;
1539                         }
1540                         /* FALLTHROUGH */
1541 #endif /* IPSEC */
1542
1543                 default:
1544                         error = ENOPROTOOPT;
1545                         break;
1546                 }
1547                 break;
1548         }
1549         return (error);
1550 }
1551
1552 /*
1553  * Routine called from ip_output() to loop back a copy of an IP multicast
1554  * packet to the input queue of a specified interface.  Note that this
1555  * calls the output routine of the loopback "driver", but with an interface
1556  * pointer that might NOT be a loopback interface -- evil, but easier than
1557  * replicating that code here.
1558  */
1559 static void
1560 ip_mloopback(struct ifnet *ifp, const struct mbuf *m, int hlen)
1561 {
1562         struct ip *ip;
1563         struct mbuf *copym;
1564
1565         /*
1566          * Make a deep copy of the packet because we're going to
1567          * modify the pack in order to generate checksums.
1568          */
1569         copym = m_dup(m, M_NOWAIT);
1570         if (copym != NULL && (!M_WRITABLE(copym) || copym->m_len < hlen))
1571                 copym = m_pullup(copym, hlen);
1572         if (copym != NULL) {
1573                 /* If needed, compute the checksum and mark it as valid. */
1574                 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
1575                         in_delayed_cksum(copym);
1576                         copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1577                         copym->m_pkthdr.csum_flags |=
1578                             CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1579                         copym->m_pkthdr.csum_data = 0xffff;
1580                 }
1581                 /*
1582                  * We don't bother to fragment if the IP length is greater
1583                  * than the interface's MTU.  Can this possibly matter?
1584                  */
1585                 ip = mtod(copym, struct ip *);
1586                 ip->ip_sum = 0;
1587                 ip->ip_sum = in_cksum(copym, hlen);
1588                 if_simloop(ifp, copym, AF_INET, 0);
1589         }
1590 }