sys/netinet/ip_output.c

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