sys/netinet/udp_usrreq.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
   5  *      The Regents of the University of California.
   6  * Copyright (c) 2008 Robert N. M. Watson
   7  * Copyright (c) 2010-2011 Juniper Networks, Inc.
   8  * Copyright (c) 2014 Kevin Lo
   9  * All rights reserved.
  10  *
  11  * Portions of this software were developed by Robert N. M. Watson under
  12  * contract to Juniper Networks, Inc.
  13  *
  14  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions
  16  * are met:
  17  * 1. Redistributions of source code must retain the above copyright
  18  *    notice, this list of conditions and the following disclaimer.
  19  * 2. Redistributions in binary form must reproduce the above copyright
  20  *    notice, this list of conditions and the following disclaimer in the
  21  *    documentation and/or other materials provided with the distribution.
  22  * 3. Neither the name of the University nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  *
  38  *      @(#)udp_usrreq.c        8.6 (Berkeley) 5/23/95
  39  */
  40
  41 #include <sys/cdefs.h>
  42 __FBSDID("$FreeBSD$");
  43
  44 #include "opt_inet.h"
  45 #include "opt_inet6.h"
  46 #include "opt_ipsec.h"
  47 #include "opt_route.h"
  48 #include "opt_rss.h"
  49
  50 #include <sys/param.h>
  51 #include <sys/domain.h>
  52 #include <sys/eventhandler.h>
  53 #include <sys/jail.h>
  54 #include <sys/kernel.h>
  55 #include <sys/lock.h>
  56 #include <sys/malloc.h>
  57 #include <sys/mbuf.h>
  58 #include <sys/priv.h>
  59 #include <sys/proc.h>
  60 #include <sys/protosw.h>
  61 #include <sys/sdt.h>
  62 #include <sys/signalvar.h>
  63 #include <sys/socket.h>
  64 #include <sys/socketvar.h>
  65 #include <sys/sx.h>
  66 #include <sys/sysctl.h>
  67 #include <sys/syslog.h>
  68 #include <sys/systm.h>
  69
  70 #include <vm/uma.h>
  71
  72 #include <net/if.h>
  73 #include <net/if_var.h>
  74 #include <net/route.h>
  75 #include <net/route/nhop.h>
  76 #include <net/rss_config.h>
  77
  78 #include <netinet/in.h>
  79 #include <netinet/in_kdtrace.h>
  80 #include <netinet/in_fib.h>
  81 #include <netinet/in_pcb.h>
  82 #include <netinet/in_systm.h>
  83 #include <netinet/in_var.h>
  84 #include <netinet/ip.h>
  85 #ifdef INET6
  86 #include <netinet/ip6.h>
  87 #endif
  88 #include <netinet/ip_icmp.h>
  89 #include <netinet/icmp_var.h>
  90 #include <netinet/ip_var.h>
  91 #include <netinet/ip_options.h>
  92 #ifdef INET6
  93 #include <netinet6/ip6_var.h>
  94 #endif
  95 #include <netinet/udp.h>
  96 #include <netinet/udp_var.h>
  97 #include <netinet/udplite.h>
  98 #include <netinet/in_rss.h>
  99
 100 #include <netipsec/ipsec_support.h>
 101
 102 #include <machine/in_cksum.h>
 103
 104 #include <security/mac/mac_framework.h>
 105
 106 /*
 107  * UDP and UDP-Lite protocols implementation.
 108  * Per RFC 768, August, 1980.
 109  * Per RFC 3828, July, 2004.
 110  */
 111
 112 /*
 113  * BSD 4.2 defaulted the udp checksum to be off.  Turning off udp checksums
 114  * removes the only data integrity mechanism for packets and malformed
 115  * packets that would otherwise be discarded due to bad checksums, and may
 116  * cause problems (especially for NFS data blocks).
 117  */
 118 VNET_DEFINE(int, udp_cksum) = 1;
 119 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_VNET | CTLFLAG_RW,
 120     &VNET_NAME(udp_cksum), 0, "compute udp checksum");
 121
 122 VNET_DEFINE(int, udp_log_in_vain) = 0;
 123 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_VNET | CTLFLAG_RW,
 124     &VNET_NAME(udp_log_in_vain), 0, "Log all incoming UDP packets");
 125
 126 VNET_DEFINE(int, udp_blackhole) = 0;
 127 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW,
 128     &VNET_NAME(udp_blackhole), 0,
 129     "Do not send port unreachables for refused connects");
 130 VNET_DEFINE(bool, udp_blackhole_local) = false;
 131 SYSCTL_BOOL(_net_inet_udp, OID_AUTO, blackhole_local, CTLFLAG_VNET |
 132     CTLFLAG_RW, &VNET_NAME(udp_blackhole_local), false,
 133     "Enforce net.inet.udp.blackhole for locally originated packets");
 134
 135 u_long  udp_sendspace = 9216;           /* really max datagram size */
 136 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
 137     &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
 138
 139 u_long  udp_recvspace = 40 * (1024 +
 140 #ifdef INET6
 141                                       sizeof(struct sockaddr_in6)
 142 #else
 143                                       sizeof(struct sockaddr_in)
 144 #endif
 145                                       );        /* 40 1K datagrams */
 146
 147 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
 148     &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
 149
 150 VNET_DEFINE(struct inpcbinfo, udbinfo);
 151 VNET_DEFINE(struct inpcbinfo, ulitecbinfo);
 152 VNET_DEFINE_STATIC(uma_zone_t, udpcb_zone);
 153 #define V_udpcb_zone                    VNET(udpcb_zone)
 154
 155 #ifndef UDBHASHSIZE
 156 #define UDBHASHSIZE     128
 157 #endif
 158
 159 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat);          /* from udp_var.h */
 160 VNET_PCPUSTAT_SYSINIT(udpstat);
 161 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat,
 162     udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)");
 163
 164 #ifdef VIMAGE
 165 VNET_PCPUSTAT_SYSUNINIT(udpstat);
 166 #endif /* VIMAGE */
 167 #ifdef INET
 168 static void     udp_detach(struct socket *so);
 169 static int      udp_output(struct inpcb *, struct mbuf *, struct sockaddr *,
 170                     struct mbuf *, struct thread *, int);
 171 #endif
 172
 173 INPCBSTORAGE_DEFINE(udpcbstor, "udpinp", "udp_inpcb", "udp", "udphash");
 174 INPCBSTORAGE_DEFINE(udplitecbstor, "udpliteinp", "udplite_inpcb", "udplite",
 175     "udplitehash");
 176
 177 static void
 178 udp_vnet_init(void *arg __unused)
 179 {
 180
 181         /*
 182          * For now default to 2-tuple UDP hashing - until the fragment
 183          * reassembly code can also update the flowid.
 184          *
 185          * Once we can calculate the flowid that way and re-establish
 186          * a 4-tuple, flip this to 4-tuple.
 187          */
 188         in_pcbinfo_init(&V_udbinfo, &udpcbstor, UDBHASHSIZE, UDBHASHSIZE);
 189         V_udpcb_zone = uma_zcreate("udpcb", sizeof(struct udpcb),
 190             NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
 191         uma_zone_set_max(V_udpcb_zone, maxsockets);
 192         uma_zone_set_warning(V_udpcb_zone, "kern.ipc.maxsockets limit reached");
 193
 194         /* Additional pcbinfo for UDP-Lite */
 195         in_pcbinfo_init(&V_ulitecbinfo, &udplitecbstor, UDBHASHSIZE,
 196             UDBHASHSIZE);
 197 }
 198 VNET_SYSINIT(udp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
 199     udp_vnet_init, NULL);
 200
 201 /*
 202  * Kernel module interface for updating udpstat.  The argument is an index
 203  * into udpstat treated as an array of u_long.  While this encodes the
 204  * general layout of udpstat into the caller, it doesn't encode its location,
 205  * so that future changes to add, for example, per-CPU stats support won't
 206  * cause binary compatibility problems for kernel modules.
 207  */
 208 void
 209 kmod_udpstat_inc(int statnum)
 210 {
 211
 212         counter_u64_add(VNET(udpstat)[statnum], 1);
 213 }
 214
 215 int
 216 udp_newudpcb(struct inpcb *inp)
 217 {
 218         struct udpcb *up;
 219
 220         up = uma_zalloc(V_udpcb_zone, M_NOWAIT | M_ZERO);
 221         if (up == NULL)
 222                 return (ENOBUFS);
 223         inp->inp_ppcb = up;
 224         return (0);
 225 }
 226
 227 void
 228 udp_discardcb(struct udpcb *up)
 229 {
 230
 231         uma_zfree(V_udpcb_zone, up);
 232 }
 233
 234 #ifdef VIMAGE
 235 static void
 236 udp_destroy(void *unused __unused)
 237 {
 238
 239         in_pcbinfo_destroy(&V_udbinfo);
 240         uma_zdestroy(V_udpcb_zone);
 241 }
 242 VNET_SYSUNINIT(udp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udp_destroy, NULL);
 243
 244 static void
 245 udplite_destroy(void *unused __unused)
 246 {
 247
 248         in_pcbinfo_destroy(&V_ulitecbinfo);
 249 }
 250 VNET_SYSUNINIT(udplite, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udplite_destroy,
 251     NULL);
 252 #endif
 253
 254 #ifdef INET
 255 /*
 256  * Subroutine of udp_input(), which appends the provided mbuf chain to the
 257  * passed pcb/socket.  The caller must provide a sockaddr_in via udp_in that
 258  * contains the source address.  If the socket ends up being an IPv6 socket,
 259  * udp_append() will convert to a sockaddr_in6 before passing the address
 260  * into the socket code.
 261  *
 262  * In the normal case udp_append() will return 0, indicating that you
 263  * must unlock the inp. However if a tunneling protocol is in place we increment
 264  * the inpcb refcnt and unlock the inp, on return from the tunneling protocol we
 265  * then decrement the reference count. If the inp_rele returns 1, indicating the
 266  * inp is gone, we return that to the caller to tell them *not* to unlock
 267  * the inp. In the case of multi-cast this will cause the distribution
 268  * to stop (though most tunneling protocols known currently do *not* use
 269  * multicast).
 270  */
 271 static int
 272 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
 273     struct sockaddr_in *udp_in)
 274 {
 275         struct sockaddr *append_sa;
 276         struct socket *so;
 277         struct mbuf *tmpopts, *opts = NULL;
 278 #ifdef INET6
 279         struct sockaddr_in6 udp_in6;
 280 #endif
 281         struct udpcb *up;
 282         bool filtered;
 283
 284         INP_LOCK_ASSERT(inp);
 285
 286         /*
 287          * Engage the tunneling protocol.
 288          */
 289         up = intoudpcb(inp);
 290         if (up->u_tun_func != NULL) {
 291                 in_pcbref(inp);
 292                 INP_RUNLOCK(inp);
 293                 filtered = (*up->u_tun_func)(n, off, inp, (struct sockaddr *)&udp_in[0],
 294                     up->u_tun_ctx);
 295                 INP_RLOCK(inp);
 296                 if (filtered)
 297                         return (in_pcbrele_rlocked(inp));
 298         }
 299
 300         off += sizeof(struct udphdr);
 301
 302 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 303         /* Check AH/ESP integrity. */
 304         if (IPSEC_ENABLED(ipv4) &&
 305             IPSEC_CHECK_POLICY(ipv4, n, inp) != 0) {
 306                 m_freem(n);
 307                 return (0);
 308         }
 309         if (up->u_flags & UF_ESPINUDP) {/* IPSec UDP encaps. */
 310                 if (IPSEC_ENABLED(ipv4) &&
 311                     UDPENCAP_INPUT(n, off, AF_INET) != 0)
 312                         return (0);     /* Consumed. */
 313         }
 314 #endif /* IPSEC */
 315 #ifdef MAC
 316         if (mac_inpcb_check_deliver(inp, n) != 0) {
 317                 m_freem(n);
 318                 return (0);
 319         }
 320 #endif /* MAC */
 321         if (inp->inp_flags & INP_CONTROLOPTS ||
 322             inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
 323 #ifdef INET6
 324                 if (inp->inp_vflag & INP_IPV6)
 325                         (void)ip6_savecontrol_v4(inp, n, &opts, NULL);
 326                 else
 327 #endif /* INET6 */
 328                         ip_savecontrol(inp, &opts, ip, n);
 329         }
 330         if ((inp->inp_vflag & INP_IPV4) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
 331                 tmpopts = sbcreatecontrol(&udp_in[1],
 332                     sizeof(struct sockaddr_in), IP_ORIGDSTADDR, IPPROTO_IP,
 333                     M_NOWAIT);
 334                 if (tmpopts) {
 335                         if (opts) {
 336                                 tmpopts->m_next = opts;
 337                                 opts = tmpopts;
 338                         } else
 339                                 opts = tmpopts;
 340                 }
 341         }
 342 #ifdef INET6
 343         if (inp->inp_vflag & INP_IPV6) {
 344                 bzero(&udp_in6, sizeof(udp_in6));
 345                 udp_in6.sin6_len = sizeof(udp_in6);
 346                 udp_in6.sin6_family = AF_INET6;
 347                 in6_sin_2_v4mapsin6(&udp_in[0], &udp_in6);
 348                 append_sa = (struct sockaddr *)&udp_in6;
 349         } else
 350 #endif /* INET6 */
 351                 append_sa = (struct sockaddr *)&udp_in[0];
 352         m_adj(n, off);
 353
 354         so = inp->inp_socket;
 355         SOCKBUF_LOCK(&so->so_rcv);
 356         if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
 357                 soroverflow_locked(so);
 358                 m_freem(n);
 359                 if (opts)
 360                         m_freem(opts);
 361                 UDPSTAT_INC(udps_fullsock);
 362         } else
 363                 sorwakeup_locked(so);
 364         return (0);
 365 }
 366
 367 static bool
 368 udp_multi_match(const struct inpcb *inp, void *v)
 369 {
 370         struct ip *ip = v;
 371         struct udphdr *uh = (struct udphdr *)(ip + 1);
 372
 373         if (inp->inp_lport != uh->uh_dport)
 374                 return (false);
 375 #ifdef INET6
 376         if ((inp->inp_vflag & INP_IPV4) == 0)
 377                 return (false);
 378 #endif
 379         if (inp->inp_laddr.s_addr != INADDR_ANY &&
 380             inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
 381                 return (false);
 382         if (inp->inp_faddr.s_addr != INADDR_ANY &&
 383             inp->inp_faddr.s_addr != ip->ip_src.s_addr)
 384                 return (false);
 385         if (inp->inp_fport != 0 &&
 386             inp->inp_fport != uh->uh_sport)
 387                 return (false);
 388
 389         return (true);
 390 }
 391
 392 static int
 393 udp_multi_input(struct mbuf *m, int proto, struct sockaddr_in *udp_in)
 394 {
 395         struct ip *ip = mtod(m, struct ip *);
 396         struct inpcb_iterator inpi = INP_ITERATOR(udp_get_inpcbinfo(proto),
 397             INPLOOKUP_RLOCKPCB, udp_multi_match, ip);
 398 #ifdef KDTRACE_HOOKS
 399         struct udphdr *uh = (struct udphdr *)(ip + 1);
 400 #endif
 401         struct inpcb *inp;
 402         struct mbuf *n;
 403         int appends = 0;
 404
 405         MPASS(ip->ip_hl == sizeof(struct ip) >> 2);
 406
 407         while ((inp = inp_next(&inpi)) != NULL) {
 408                 /*
 409                  * XXXRW: Because we weren't holding either the inpcb
 410                  * or the hash lock when we checked for a match
 411                  * before, we should probably recheck now that the
 412                  * inpcb lock is held.
 413                  */
 414                 /*
 415                  * Handle socket delivery policy for any-source
 416                  * and source-specific multicast. [RFC3678]
 417                  */
 418                 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
 419                         struct ip_moptions      *imo;
 420                         struct sockaddr_in       group;
 421                         int                      blocked;
 422
 423                         imo = inp->inp_moptions;
 424                         if (imo == NULL)
 425                                 continue;
 426                         bzero(&group, sizeof(struct sockaddr_in));
 427                         group.sin_len = sizeof(struct sockaddr_in);
 428                         group.sin_family = AF_INET;
 429                         group.sin_addr = ip->ip_dst;
 430
 431                         blocked = imo_multi_filter(imo, m->m_pkthdr.rcvif,
 432                                 (struct sockaddr *)&group,
 433                                 (struct sockaddr *)&udp_in[0]);
 434                         if (blocked != MCAST_PASS) {
 435                                 if (blocked == MCAST_NOTGMEMBER)
 436                                         IPSTAT_INC(ips_notmember);
 437                                 if (blocked == MCAST_NOTSMEMBER ||
 438                                     blocked == MCAST_MUTED)
 439                                         UDPSTAT_INC(udps_filtermcast);
 440                                 continue;
 441                         }
 442                 }
 443                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) != NULL) {
 444                         if (proto == IPPROTO_UDPLITE)
 445                                 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 446                         else
 447                                 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 448                         if (udp_append(inp, ip, n, sizeof(struct ip), udp_in)) {
 449                                 INP_RUNLOCK(inp);
 450                                 break;
 451                         } else
 452                                 appends++;
 453                 }
 454                 /*
 455                  * Don't look for additional matches if this one does
 456                  * not have either the SO_REUSEPORT or SO_REUSEADDR
 457                  * socket options set.  This heuristic avoids
 458                  * searching through all pcbs in the common case of a
 459                  * non-shared port.  It assumes that an application
 460                  * will never clear these options after setting them.
 461                  */
 462                 if ((inp->inp_socket->so_options &
 463                     (SO_REUSEPORT|SO_REUSEPORT_LB|SO_REUSEADDR)) == 0) {
 464                         INP_RUNLOCK(inp);
 465                         break;
 466                 }
 467         }
 468
 469         if (appends == 0) {
 470                 /*
 471                  * No matching pcb found; discard datagram.  (No need
 472                  * to send an ICMP Port Unreachable for a broadcast
 473                  * or multicast datgram.)
 474                  */
 475                 UDPSTAT_INC(udps_noport);
 476                 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)))
 477                         UDPSTAT_INC(udps_noportmcast);
 478                 else
 479                         UDPSTAT_INC(udps_noportbcast);
 480         }
 481         m_freem(m);
 482
 483         return (IPPROTO_DONE);
 484 }
 485
 486 static int
 487 udp_input(struct mbuf **mp, int *offp, int proto)
 488 {
 489         struct ip *ip;
 490         struct udphdr *uh;
 491         struct ifnet *ifp;
 492         struct inpcb *inp;
 493         uint16_t len, ip_len;
 494         struct inpcbinfo *pcbinfo;
 495         struct sockaddr_in udp_in[2];
 496         struct mbuf *m;
 497         struct m_tag *fwd_tag;
 498         int cscov_partial, iphlen;
 499
 500         m = *mp;
 501         iphlen = *offp;
 502         ifp = m->m_pkthdr.rcvif;
 503         *mp = NULL;
 504         UDPSTAT_INC(udps_ipackets);
 505
 506         /*
 507          * Strip IP options, if any; should skip this, make available to
 508          * user, and use on returned packets, but we don't yet have a way to
 509          * check the checksum with options still present.
 510          */
 511         if (iphlen > sizeof (struct ip)) {
 512                 ip_stripoptions(m);
 513                 iphlen = sizeof(struct ip);
 514         }
 515
 516         /*
 517          * Get IP and UDP header together in first mbuf.
 518          */
 519         if (m->m_len < iphlen + sizeof(struct udphdr)) {
 520                 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) {
 521                         UDPSTAT_INC(udps_hdrops);
 522                         return (IPPROTO_DONE);
 523                 }
 524         }
 525         ip = mtod(m, struct ip *);
 526         uh = (struct udphdr *)((caddr_t)ip + iphlen);
 527         cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0;
 528
 529         /*
 530          * Destination port of 0 is illegal, based on RFC768.
 531          */
 532         if (uh->uh_dport == 0)
 533                 goto badunlocked;
 534
 535         /*
 536          * Construct sockaddr format source address.  Stuff source address
 537          * and datagram in user buffer.
 538          */
 539         bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2);
 540         udp_in[0].sin_len = sizeof(struct sockaddr_in);
 541         udp_in[0].sin_family = AF_INET;
 542         udp_in[0].sin_port = uh->uh_sport;
 543         udp_in[0].sin_addr = ip->ip_src;
 544         udp_in[1].sin_len = sizeof(struct sockaddr_in);
 545         udp_in[1].sin_family = AF_INET;
 546         udp_in[1].sin_port = uh->uh_dport;
 547         udp_in[1].sin_addr = ip->ip_dst;
 548
 549         /*
 550          * Make mbuf data length reflect UDP length.  If not enough data to
 551          * reflect UDP length, drop.
 552          */
 553         len = ntohs((u_short)uh->uh_ulen);
 554         ip_len = ntohs(ip->ip_len) - iphlen;
 555         if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) {
 556                 /* Zero means checksum over the complete packet. */
 557                 if (len == 0)
 558                         len = ip_len;
 559                 cscov_partial = 0;
 560         }
 561         if (ip_len != len) {
 562                 if (len > ip_len || len < sizeof(struct udphdr)) {
 563                         UDPSTAT_INC(udps_badlen);
 564                         goto badunlocked;
 565                 }
 566                 if (proto == IPPROTO_UDP)
 567                         m_adj(m, len - ip_len);
 568         }
 569
 570         /*
 571          * Checksum extended UDP header and data.
 572          */
 573         if (uh->uh_sum) {
 574                 u_short uh_sum;
 575
 576                 if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
 577                     !cscov_partial) {
 578                         if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
 579                                 uh_sum = m->m_pkthdr.csum_data;
 580                         else
 581                                 uh_sum = in_pseudo(ip->ip_src.s_addr,
 582                                     ip->ip_dst.s_addr, htonl((u_short)len +
 583                                     m->m_pkthdr.csum_data + proto));
 584                         uh_sum ^= 0xffff;
 585                 } else {
 586                         char b[offsetof(struct ipovly, ih_src)];
 587                         struct ipovly *ipov = (struct ipovly *)ip;
 588
 589                         bcopy(ipov, b, sizeof(b));
 590                         bzero(ipov, sizeof(ipov->ih_x1));
 591                         ipov->ih_len = (proto == IPPROTO_UDP) ?
 592                             uh->uh_ulen : htons(ip_len);
 593                         uh_sum = in_cksum(m, len + sizeof (struct ip));
 594                         bcopy(b, ipov, sizeof(b));
 595                 }
 596                 if (uh_sum) {
 597                         UDPSTAT_INC(udps_badsum);
 598                         m_freem(m);
 599                         return (IPPROTO_DONE);
 600                 }
 601         } else {
 602                 if (proto == IPPROTO_UDP) {
 603                         UDPSTAT_INC(udps_nosum);
 604                 } else {
 605                         /* UDPLite requires a checksum */
 606                         /* XXX: What is the right UDPLite MIB counter here? */
 607                         m_freem(m);
 608                         return (IPPROTO_DONE);
 609                 }
 610         }
 611
 612         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
 613             in_broadcast(ip->ip_dst, ifp))
 614                 return (udp_multi_input(m, proto, udp_in));
 615
 616         pcbinfo = udp_get_inpcbinfo(proto);
 617
 618         /*
 619          * Locate pcb for datagram.
 620          *
 621          * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
 622          */
 623         if ((m->m_flags & M_IP_NEXTHOP) &&
 624             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 625                 struct sockaddr_in *next_hop;
 626
 627                 next_hop = (struct sockaddr_in *)(fwd_tag + 1);
 628
 629                 /*
 630                  * Transparently forwarded. Pretend to be the destination.
 631                  * Already got one like this?
 632                  */
 633                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 634                     ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m);
 635                 if (!inp) {
 636                         /*
 637                          * It's new.  Try to find the ambushing socket.
 638                          * Because we've rewritten the destination address,
 639                          * any hardware-generated hash is ignored.
 640                          */
 641                         inp = in_pcblookup(pcbinfo, ip->ip_src,
 642                             uh->uh_sport, next_hop->sin_addr,
 643                             next_hop->sin_port ? htons(next_hop->sin_port) :
 644                             uh->uh_dport, INPLOOKUP_WILDCARD |
 645                             INPLOOKUP_RLOCKPCB, ifp);
 646                 }
 647                 /* Remove the tag from the packet. We don't need it anymore. */
 648                 m_tag_delete(m, fwd_tag);
 649                 m->m_flags &= ~M_IP_NEXTHOP;
 650         } else
 651                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 652                     ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD |
 653                     INPLOOKUP_RLOCKPCB, ifp, m);
 654         if (inp == NULL) {
 655                 if (V_udp_log_in_vain) {
 656                         char src[INET_ADDRSTRLEN];
 657                         char dst[INET_ADDRSTRLEN];
 658
 659                         log(LOG_INFO,
 660                             "Connection attempt to UDP %s:%d from %s:%d\n",
 661                             inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport),
 662                             inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport));
 663                 }
 664                 if (proto == IPPROTO_UDPLITE)
 665                         UDPLITE_PROBE(receive, NULL, NULL, ip, NULL, uh);
 666                 else
 667                         UDP_PROBE(receive, NULL, NULL, ip, NULL, uh);
 668                 UDPSTAT_INC(udps_noport);
 669                 if (m->m_flags & (M_BCAST | M_MCAST)) {
 670                         UDPSTAT_INC(udps_noportbcast);
 671                         goto badunlocked;
 672                 }
 673                 if (V_udp_blackhole && (V_udp_blackhole_local ||
 674                     !in_localip(ip->ip_src)))
 675                         goto badunlocked;
 676                 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
 677                         goto badunlocked;
 678                 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
 679                 return (IPPROTO_DONE);
 680         }
 681
 682         /*
 683          * Check the minimum TTL for socket.
 684          */
 685         INP_RLOCK_ASSERT(inp);
 686         if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
 687                 if (proto == IPPROTO_UDPLITE)
 688                         UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 689                 else
 690                         UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 691                 INP_RUNLOCK(inp);
 692                 m_freem(m);
 693                 return (IPPROTO_DONE);
 694         }
 695         if (cscov_partial) {
 696                 struct udpcb *up;
 697
 698                 up = intoudpcb(inp);
 699                 if (up->u_rxcslen == 0 || up->u_rxcslen > len) {
 700                         INP_RUNLOCK(inp);
 701                         m_freem(m);
 702                         return (IPPROTO_DONE);
 703                 }
 704         }
 705
 706         if (proto == IPPROTO_UDPLITE)
 707                 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 708         else
 709                 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 710         if (udp_append(inp, ip, m, iphlen, udp_in) == 0)
 711                 INP_RUNLOCK(inp);
 712         return (IPPROTO_DONE);
 713
 714 badunlocked:
 715         m_freem(m);
 716         return (IPPROTO_DONE);
 717 }
 718 #endif /* INET */
 719
 720 /*
 721  * Notify a udp user of an asynchronous error; just wake up so that they can
 722  * collect error status.
 723  */
 724 struct inpcb *
 725 udp_notify(struct inpcb *inp, int errno)
 726 {
 727
 728         INP_WLOCK_ASSERT(inp);
 729         if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
 730              errno == EHOSTDOWN) && inp->inp_route.ro_nh) {
 731                 NH_FREE(inp->inp_route.ro_nh);
 732                 inp->inp_route.ro_nh = (struct nhop_object *)NULL;
 733         }
 734
 735         inp->inp_socket->so_error = errno;
 736         sorwakeup(inp->inp_socket);
 737         sowwakeup(inp->inp_socket);
 738         return (inp);
 739 }
 740
 741 #ifdef INET
 742 static void
 743 udp_common_ctlinput(struct icmp *icmp, struct inpcbinfo *pcbinfo)
 744 {
 745         struct ip *ip = &icmp->icmp_ip;
 746         struct udphdr *uh;
 747         struct inpcb *inp;
 748
 749         if (icmp_errmap(icmp) == 0)
 750                 return;
 751
 752         uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
 753         inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport, ip->ip_src,
 754             uh->uh_sport, INPLOOKUP_WLOCKPCB, NULL);
 755         if (inp != NULL) {
 756                 INP_WLOCK_ASSERT(inp);
 757                 if (inp->inp_socket != NULL)
 758                         udp_notify(inp, icmp_errmap(icmp));
 759                 INP_WUNLOCK(inp);
 760         } else {
 761                 inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport,
 762                     ip->ip_src, uh->uh_sport,
 763                     INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 764                 if (inp != NULL) {
 765                         struct udpcb *up;
 766                         udp_tun_icmp_t *func;
 767
 768                         up = intoudpcb(inp);
 769                         func = up->u_icmp_func;
 770                         INP_RUNLOCK(inp);
 771                         if (func != NULL)
 772                                 func(icmp);
 773                 }
 774         }
 775 }
 776
 777 static void
 778 udp_ctlinput(struct icmp *icmp)
 779 {
 780
 781         return (udp_common_ctlinput(icmp, &V_udbinfo));
 782 }
 783
 784 static void
 785 udplite_ctlinput(struct icmp *icmp)
 786 {
 787
 788         return (udp_common_ctlinput(icmp, &V_ulitecbinfo));
 789 }
 790 #endif /* INET */
 791
 792 static int
 793 udp_pcblist(SYSCTL_HANDLER_ARGS)
 794 {
 795         struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_udbinfo,
 796             INPLOOKUP_RLOCKPCB);
 797         struct xinpgen xig;
 798         struct inpcb *inp;
 799         int error;
 800
 801         if (req->newptr != 0)
 802                 return (EPERM);
 803
 804         if (req->oldptr == 0) {
 805                 int n;
 806
 807                 n = V_udbinfo.ipi_count;
 808                 n += imax(n / 8, 10);
 809                 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
 810                 return (0);
 811         }
 812
 813         if ((error = sysctl_wire_old_buffer(req, 0)) != 0)
 814                 return (error);
 815
 816         bzero(&xig, sizeof(xig));
 817         xig.xig_len = sizeof xig;
 818         xig.xig_count = V_udbinfo.ipi_count;
 819         xig.xig_gen = V_udbinfo.ipi_gencnt;
 820         xig.xig_sogen = so_gencnt;
 821         error = SYSCTL_OUT(req, &xig, sizeof xig);
 822         if (error)
 823                 return (error);
 824
 825         while ((inp = inp_next(&inpi)) != NULL) {
 826                 if (inp->inp_gencnt <= xig.xig_gen &&
 827                     cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
 828                         struct xinpcb xi;
 829
 830                         in_pcbtoxinpcb(inp, &xi);
 831                         error = SYSCTL_OUT(req, &xi, sizeof xi);
 832                         if (error) {
 833                                 INP_RUNLOCK(inp);
 834                                 break;
 835                         }
 836                 }
 837         }
 838
 839         if (!error) {
 840                 /*
 841                  * Give the user an updated idea of our state.  If the
 842                  * generation differs from what we told her before, she knows
 843                  * that something happened while we were processing this
 844                  * request, and it might be necessary to retry.
 845                  */
 846                 xig.xig_gen = V_udbinfo.ipi_gencnt;
 847                 xig.xig_sogen = so_gencnt;
 848                 xig.xig_count = V_udbinfo.ipi_count;
 849                 error = SYSCTL_OUT(req, &xig, sizeof xig);
 850         }
 851
 852         return (error);
 853 }
 854
 855 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
 856     CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
 857     udp_pcblist, "S,xinpcb",
 858     "List of active UDP sockets");
 859
 860 #ifdef INET
 861 static int
 862 udp_getcred(SYSCTL_HANDLER_ARGS)
 863 {
 864         struct xucred xuc;
 865         struct sockaddr_in addrs[2];
 866         struct epoch_tracker et;
 867         struct inpcb *inp;
 868         int error;
 869
 870         error = priv_check(req->td, PRIV_NETINET_GETCRED);
 871         if (error)
 872                 return (error);
 873         error = SYSCTL_IN(req, addrs, sizeof(addrs));
 874         if (error)
 875                 return (error);
 876         NET_EPOCH_ENTER(et);
 877         inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
 878             addrs[0].sin_addr, addrs[0].sin_port,
 879             INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 880         NET_EPOCH_EXIT(et);
 881         if (inp != NULL) {
 882                 INP_RLOCK_ASSERT(inp);
 883                 if (inp->inp_socket == NULL)
 884                         error = ENOENT;
 885                 if (error == 0)
 886                         error = cr_canseeinpcb(req->td->td_ucred, inp);
 887                 if (error == 0)
 888                         cru2x(inp->inp_cred, &xuc);
 889                 INP_RUNLOCK(inp);
 890         } else
 891                 error = ENOENT;
 892         if (error == 0)
 893                 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
 894         return (error);
 895 }
 896
 897 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
 898     CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
 899     0, 0, udp_getcred, "S,xucred",
 900     "Get the xucred of a UDP connection");
 901 #endif /* INET */
 902
 903 int
 904 udp_ctloutput(struct socket *so, struct sockopt *sopt)
 905 {
 906         struct inpcb *inp;
 907         struct udpcb *up;
 908         int isudplite, error, optval;
 909
 910         error = 0;
 911         isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0;
 912         inp = sotoinpcb(so);
 913         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
 914         INP_WLOCK(inp);
 915         if (sopt->sopt_level != so->so_proto->pr_protocol) {
 916 #ifdef INET6
 917                 if (INP_CHECK_SOCKAF(so, AF_INET6)) {
 918                         INP_WUNLOCK(inp);
 919                         error = ip6_ctloutput(so, sopt);
 920                 }
 921 #endif
 922 #if defined(INET) && defined(INET6)
 923                 else
 924 #endif
 925 #ifdef INET
 926                 {
 927                         INP_WUNLOCK(inp);
 928                         error = ip_ctloutput(so, sopt);
 929                 }
 930 #endif
 931                 return (error);
 932         }
 933
 934         switch (sopt->sopt_dir) {
 935         case SOPT_SET:
 936                 switch (sopt->sopt_name) {
 937 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 938 #ifdef INET
 939                 case UDP_ENCAP:
 940                         if (!IPSEC_ENABLED(ipv4)) {
 941                                 INP_WUNLOCK(inp);
 942                                 return (ENOPROTOOPT);
 943                         }
 944                         error = UDPENCAP_PCBCTL(inp, sopt);
 945                         break;
 946 #endif /* INET */
 947 #endif /* IPSEC */
 948                 case UDPLITE_SEND_CSCOV:
 949                 case UDPLITE_RECV_CSCOV:
 950                         if (!isudplite) {
 951                                 INP_WUNLOCK(inp);
 952                                 error = ENOPROTOOPT;
 953                                 break;
 954                         }
 955                         INP_WUNLOCK(inp);
 956                         error = sooptcopyin(sopt, &optval, sizeof(optval),
 957                             sizeof(optval));
 958                         if (error != 0)
 959                                 break;
 960                         inp = sotoinpcb(so);
 961                         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
 962                         INP_WLOCK(inp);
 963                         up = intoudpcb(inp);
 964                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
 965                         if ((optval != 0 && optval < 8) || (optval > 65535)) {
 966                                 INP_WUNLOCK(inp);
 967                                 error = EINVAL;
 968                                 break;
 969                         }
 970                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
 971                                 up->u_txcslen = optval;
 972                         else
 973                                 up->u_rxcslen = optval;
 974                         INP_WUNLOCK(inp);
 975                         break;
 976                 default:
 977                         INP_WUNLOCK(inp);
 978                         error = ENOPROTOOPT;
 979                         break;
 980                 }
 981                 break;
 982         case SOPT_GET:
 983                 switch (sopt->sopt_name) {
 984 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 985 #ifdef INET
 986                 case UDP_ENCAP:
 987                         if (!IPSEC_ENABLED(ipv4)) {
 988                                 INP_WUNLOCK(inp);
 989                                 return (ENOPROTOOPT);
 990                         }
 991                         error = UDPENCAP_PCBCTL(inp, sopt);
 992                         break;
 993 #endif /* INET */
 994 #endif /* IPSEC */
 995                 case UDPLITE_SEND_CSCOV:
 996                 case UDPLITE_RECV_CSCOV:
 997                         if (!isudplite) {
 998                                 INP_WUNLOCK(inp);
 999                                 error = ENOPROTOOPT;
1000                                 break;
1001                         }
1002                         up = intoudpcb(inp);
1003                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1004                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
1005                                 optval = up->u_txcslen;
1006                         else
1007                                 optval = up->u_rxcslen;
1008                         INP_WUNLOCK(inp);
1009                         error = sooptcopyout(sopt, &optval, sizeof(optval));
1010                         break;
1011                 default:
1012                         INP_WUNLOCK(inp);
1013                         error = ENOPROTOOPT;
1014                         break;
1015                 }
1016                 break;
1017         }
1018         return (error);
1019 }
1020
1021 #ifdef INET
1022 #ifdef INET6
1023 /* The logic here is derived from ip6_setpktopt(). See comments there. */
1024 static int
1025 udp_v4mapped_pktinfo(struct cmsghdr *cm, struct sockaddr_in * src,
1026     struct inpcb *inp, int flags)
1027 {
1028         struct ifnet *ifp;
1029         struct in6_pktinfo *pktinfo;
1030         struct in_addr ia;
1031
1032         if ((flags & PRUS_IPV6) == 0)
1033                 return (0);
1034
1035         if (cm->cmsg_level != IPPROTO_IPV6)
1036                 return (0);
1037
1038         if  (cm->cmsg_type != IPV6_2292PKTINFO &&
1039             cm->cmsg_type != IPV6_PKTINFO)
1040                 return (0);
1041
1042         if (cm->cmsg_len !=
1043             CMSG_LEN(sizeof(struct in6_pktinfo)))
1044                 return (EINVAL);
1045
1046         pktinfo = (struct in6_pktinfo *)CMSG_DATA(cm);
1047         if (!IN6_IS_ADDR_V4MAPPED(&pktinfo->ipi6_addr) &&
1048             !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr))
1049                 return (EINVAL);
1050
1051         /* Validate the interface index if specified. */
1052         if (pktinfo->ipi6_ifindex) {
1053                 struct epoch_tracker et;
1054
1055                 NET_EPOCH_ENTER(et);
1056                 ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
1057                 NET_EPOCH_EXIT(et);     /* XXXGL: unsafe ifp */
1058                 if (ifp == NULL)
1059                         return (ENXIO);
1060         } else
1061                 ifp = NULL;
1062         if (ifp != NULL && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
1063                 ia.s_addr = pktinfo->ipi6_addr.s6_addr32[3];
1064                 if (in_ifhasaddr(ifp, ia) == 0)
1065                         return (EADDRNOTAVAIL);
1066         }
1067
1068         bzero(src, sizeof(*src));
1069         src->sin_family = AF_INET;
1070         src->sin_len = sizeof(*src);
1071         src->sin_port = inp->inp_lport;
1072         src->sin_addr.s_addr = pktinfo->ipi6_addr.s6_addr32[3];
1073
1074         return (0);
1075 }
1076 #endif
1077
1078 static int
1079 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
1080     struct mbuf *control, struct thread *td, int flags)
1081 {
1082         struct udpiphdr *ui;
1083         int len = m->m_pkthdr.len;
1084         struct in_addr faddr, laddr;
1085         struct cmsghdr *cm;
1086         struct inpcbinfo *pcbinfo;
1087         struct sockaddr_in *sin, src;
1088         struct epoch_tracker et;
1089         int cscov_partial = 0;
1090         int error = 0;
1091         int ipflags = 0;
1092         u_short fport, lport;
1093         u_char tos;
1094         uint8_t pr;
1095         uint16_t cscov = 0;
1096         uint32_t flowid = 0;
1097         uint8_t flowtype = M_HASHTYPE_NONE;
1098
1099         if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1100                 if (control)
1101                         m_freem(control);
1102                 m_freem(m);
1103                 return (EMSGSIZE);
1104         }
1105
1106         src.sin_family = 0;
1107         sin = (struct sockaddr_in *)addr;
1108
1109         /*
1110          * udp_output() may need to temporarily bind or connect the current
1111          * inpcb.  As such, we don't know up front whether we will need the
1112          * pcbinfo lock or not.  Do any work to decide what is needed up
1113          * front before acquiring any locks.
1114          *
1115          * We will need network epoch in either case, to safely lookup into
1116          * pcb hash.
1117          */
1118         if (sin == NULL ||
1119             (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0))
1120                 INP_WLOCK(inp);
1121         else
1122                 INP_RLOCK(inp);
1123         NET_EPOCH_ENTER(et);
1124         tos = inp->inp_ip_tos;
1125         if (control != NULL) {
1126                 /*
1127                  * XXX: Currently, we assume all the optional information is
1128                  * stored in a single mbuf.
1129                  */
1130                 if (control->m_next) {
1131                         m_freem(control);
1132                         error = EINVAL;
1133                         goto release;
1134                 }
1135                 for (; control->m_len > 0;
1136                     control->m_data += CMSG_ALIGN(cm->cmsg_len),
1137                     control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
1138                         cm = mtod(control, struct cmsghdr *);
1139                         if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
1140                             || cm->cmsg_len > control->m_len) {
1141                                 error = EINVAL;
1142                                 break;
1143                         }
1144 #ifdef INET6
1145                         error = udp_v4mapped_pktinfo(cm, &src, inp, flags);
1146                         if (error != 0)
1147                                 break;
1148 #endif
1149                         if (cm->cmsg_level != IPPROTO_IP)
1150                                 continue;
1151
1152                         switch (cm->cmsg_type) {
1153                         case IP_SENDSRCADDR:
1154                                 if (cm->cmsg_len !=
1155                                     CMSG_LEN(sizeof(struct in_addr))) {
1156                                         error = EINVAL;
1157                                         break;
1158                                 }
1159                                 bzero(&src, sizeof(src));
1160                                 src.sin_family = AF_INET;
1161                                 src.sin_len = sizeof(src);
1162                                 src.sin_port = inp->inp_lport;
1163                                 src.sin_addr =
1164                                     *(struct in_addr *)CMSG_DATA(cm);
1165                                 break;
1166
1167                         case IP_TOS:
1168                                 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) {
1169                                         error = EINVAL;
1170                                         break;
1171                                 }
1172                                 tos = *(u_char *)CMSG_DATA(cm);
1173                                 break;
1174
1175                         case IP_FLOWID:
1176                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1177                                         error = EINVAL;
1178                                         break;
1179                                 }
1180                                 flowid = *(uint32_t *) CMSG_DATA(cm);
1181                                 break;
1182
1183                         case IP_FLOWTYPE:
1184                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1185                                         error = EINVAL;
1186                                         break;
1187                                 }
1188                                 flowtype = *(uint32_t *) CMSG_DATA(cm);
1189                                 break;
1190
1191 #ifdef  RSS
1192                         case IP_RSSBUCKETID:
1193                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1194                                         error = EINVAL;
1195                                         break;
1196                                 }
1197                                 /* This is just a placeholder for now */
1198                                 break;
1199 #endif  /* RSS */
1200                         default:
1201                                 error = ENOPROTOOPT;
1202                                 break;
1203                         }
1204                         if (error)
1205                                 break;
1206                 }
1207                 m_freem(control);
1208                 control = NULL;
1209         }
1210         if (error)
1211                 goto release;
1212
1213         pr = inp->inp_socket->so_proto->pr_protocol;
1214         pcbinfo = udp_get_inpcbinfo(pr);
1215
1216         /*
1217          * If the IP_SENDSRCADDR control message was specified, override the
1218          * source address for this datagram.  Its use is invalidated if the
1219          * address thus specified is incomplete or clobbers other inpcbs.
1220          */
1221         laddr = inp->inp_laddr;
1222         lport = inp->inp_lport;
1223         if (src.sin_family == AF_INET) {
1224                 if ((lport == 0) ||
1225                     (laddr.s_addr == INADDR_ANY &&
1226                      src.sin_addr.s_addr == INADDR_ANY)) {
1227                         error = EINVAL;
1228                         goto release;
1229                 }
1230                 INP_HASH_WLOCK(pcbinfo);
1231                 error = in_pcbbind_setup(inp, (struct sockaddr *)&src,
1232                     &laddr.s_addr, &lport, td->td_ucred);
1233                 INP_HASH_WUNLOCK(pcbinfo);
1234                 if (error)
1235                         goto release;
1236         }
1237
1238         /*
1239          * If a UDP socket has been connected, then a local address/port will
1240          * have been selected and bound.
1241          *
1242          * If a UDP socket has not been connected to, then an explicit
1243          * destination address must be used, in which case a local
1244          * address/port may not have been selected and bound.
1245          */
1246         if (sin != NULL) {
1247                 INP_LOCK_ASSERT(inp);
1248                 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1249                         error = EISCONN;
1250                         goto release;
1251                 }
1252
1253                 /*
1254                  * Jail may rewrite the destination address, so let it do
1255                  * that before we use it.
1256                  */
1257                 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1258                 if (error)
1259                         goto release;
1260
1261                 /*
1262                  * If a local address or port hasn't yet been selected, or if
1263                  * the destination address needs to be rewritten due to using
1264                  * a special INADDR_ constant, invoke in_pcbconnect_setup()
1265                  * to do the heavy lifting.  Once a port is selected, we
1266                  * commit the binding back to the socket; we also commit the
1267                  * binding of the address if in jail.
1268                  *
1269                  * If we already have a valid binding and we're not
1270                  * requesting a destination address rewrite, use a fast path.
1271                  */
1272                 if (inp->inp_laddr.s_addr == INADDR_ANY ||
1273                     inp->inp_lport == 0 ||
1274                     sin->sin_addr.s_addr == INADDR_ANY ||
1275                     sin->sin_addr.s_addr == INADDR_BROADCAST) {
1276                         INP_HASH_WLOCK(pcbinfo);
1277                         error = in_pcbconnect_setup(inp, addr, &laddr.s_addr,
1278                             &lport, &faddr.s_addr, &fport, NULL,
1279                             td->td_ucred);
1280                         if (error) {
1281                                 INP_HASH_WUNLOCK(pcbinfo);
1282                                 goto release;
1283                         }
1284
1285                         /*
1286                          * XXXRW: Why not commit the port if the address is
1287                          * !INADDR_ANY?
1288                          */
1289                         /* Commit the local port if newly assigned. */
1290                         if (inp->inp_laddr.s_addr == INADDR_ANY &&
1291                             inp->inp_lport == 0) {
1292                                 INP_WLOCK_ASSERT(inp);
1293                                 /*
1294                                  * Remember addr if jailed, to prevent
1295                                  * rebinding.
1296                                  */
1297                                 if (prison_flag(td->td_ucred, PR_IP4))
1298                                         inp->inp_laddr = laddr;
1299                                 inp->inp_lport = lport;
1300                                 error = in_pcbinshash(inp);
1301                                 INP_HASH_WUNLOCK(pcbinfo);
1302                                 if (error != 0) {
1303                                         inp->inp_lport = 0;
1304                                         error = EAGAIN;
1305                                         goto release;
1306                                 }
1307                                 inp->inp_flags |= INP_ANONPORT;
1308                         } else
1309                                 INP_HASH_WUNLOCK(pcbinfo);
1310                 } else {
1311                         faddr = sin->sin_addr;
1312                         fport = sin->sin_port;
1313                 }
1314         } else {
1315                 INP_LOCK_ASSERT(inp);
1316                 faddr = inp->inp_faddr;
1317                 fport = inp->inp_fport;
1318                 if (faddr.s_addr == INADDR_ANY) {
1319                         error = ENOTCONN;
1320                         goto release;
1321                 }
1322         }
1323
1324         /*
1325          * Calculate data length and get a mbuf for UDP, IP, and possible
1326          * link-layer headers.  Immediate slide the data pointer back forward
1327          * since we won't use that space at this layer.
1328          */
1329         M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT);
1330         if (m == NULL) {
1331                 error = ENOBUFS;
1332                 goto release;
1333         }
1334         m->m_data += max_linkhdr;
1335         m->m_len -= max_linkhdr;
1336         m->m_pkthdr.len -= max_linkhdr;
1337
1338         /*
1339          * Fill in mbuf with extended UDP header and addresses and length put
1340          * into network format.
1341          */
1342         ui = mtod(m, struct udpiphdr *);
1343         bzero(ui->ui_x1, sizeof(ui->ui_x1));    /* XXX still needed? */
1344         ui->ui_v = IPVERSION << 4;
1345         ui->ui_pr = pr;
1346         ui->ui_src = laddr;
1347         ui->ui_dst = faddr;
1348         ui->ui_sport = lport;
1349         ui->ui_dport = fport;
1350         ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1351         if (pr == IPPROTO_UDPLITE) {
1352                 struct udpcb *up;
1353                 uint16_t plen;
1354
1355                 up = intoudpcb(inp);
1356                 cscov = up->u_txcslen;
1357                 plen = (u_short)len + sizeof(struct udphdr);
1358                 if (cscov >= plen)
1359                         cscov = 0;
1360                 ui->ui_len = htons(plen);
1361                 ui->ui_ulen = htons(cscov);
1362                 /*
1363                  * For UDP-Lite, checksum coverage length of zero means
1364                  * the entire UDPLite packet is covered by the checksum.
1365                  */
1366                 cscov_partial = (cscov == 0) ? 0 : 1;
1367         }
1368
1369         /*
1370          * Set the Don't Fragment bit in the IP header.
1371          */
1372         if (inp->inp_flags & INP_DONTFRAG) {
1373                 struct ip *ip;
1374
1375                 ip = (struct ip *)&ui->ui_i;
1376                 ip->ip_off |= htons(IP_DF);
1377         }
1378
1379         if (inp->inp_socket->so_options & SO_DONTROUTE)
1380                 ipflags |= IP_ROUTETOIF;
1381         if (inp->inp_socket->so_options & SO_BROADCAST)
1382                 ipflags |= IP_ALLOWBROADCAST;
1383         if (inp->inp_flags & INP_ONESBCAST)
1384                 ipflags |= IP_SENDONES;
1385
1386 #ifdef MAC
1387         mac_inpcb_create_mbuf(inp, m);
1388 #endif
1389
1390         /*
1391          * Set up checksum and output datagram.
1392          */
1393         ui->ui_sum = 0;
1394         if (pr == IPPROTO_UDPLITE) {
1395                 if (inp->inp_flags & INP_ONESBCAST)
1396                         faddr.s_addr = INADDR_BROADCAST;
1397                 if (cscov_partial) {
1398                         if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0)
1399                                 ui->ui_sum = 0xffff;
1400                 } else {
1401                         if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0)
1402                                 ui->ui_sum = 0xffff;
1403                 }
1404         } else if (V_udp_cksum) {
1405                 if (inp->inp_flags & INP_ONESBCAST)
1406                         faddr.s_addr = INADDR_BROADCAST;
1407                 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1408                     htons((u_short)len + sizeof(struct udphdr) + pr));
1409                 m->m_pkthdr.csum_flags = CSUM_UDP;
1410                 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1411         }
1412         ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len);
1413         ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;    /* XXX */
1414         ((struct ip *)ui)->ip_tos = tos;                /* XXX */
1415         UDPSTAT_INC(udps_opackets);
1416
1417         /*
1418          * Setup flowid / RSS information for outbound socket.
1419          *
1420          * Once the UDP code decides to set a flowid some other way,
1421          * this allows the flowid to be overridden by userland.
1422          */
1423         if (flowtype != M_HASHTYPE_NONE) {
1424                 m->m_pkthdr.flowid = flowid;
1425                 M_HASHTYPE_SET(m, flowtype);
1426         }
1427 #if defined(ROUTE_MPATH) || defined(RSS)
1428         else if (CALC_FLOWID_OUTBOUND_SENDTO) {
1429                 uint32_t hash_val, hash_type;
1430
1431                 hash_val = fib4_calc_packet_hash(laddr, faddr,
1432                     lport, fport, pr, &hash_type);
1433                 m->m_pkthdr.flowid = hash_val;
1434                 M_HASHTYPE_SET(m, hash_type);
1435         }
1436
1437         /*
1438          * Don't override with the inp cached flowid value.
1439          *
1440          * Depending upon the kind of send being done, the inp
1441          * flowid/flowtype values may actually not be appropriate
1442          * for this particular socket send.
1443          *
1444          * We should either leave the flowid at zero (which is what is
1445          * currently done) or set it to some software generated
1446          * hash value based on the packet contents.
1447          */
1448         ipflags |= IP_NODEFAULTFLOWID;
1449 #endif  /* RSS */
1450
1451         if (pr == IPPROTO_UDPLITE)
1452                 UDPLITE_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1453         else
1454                 UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1455         error = ip_output(m, inp->inp_options,
1456             INP_WLOCKED(inp) ? &inp->inp_route : NULL, ipflags,
1457             inp->inp_moptions, inp);
1458         INP_UNLOCK(inp);
1459         NET_EPOCH_EXIT(et);
1460         return (error);
1461
1462 release:
1463         INP_UNLOCK(inp);
1464         NET_EPOCH_EXIT(et);
1465         m_freem(m);
1466         return (error);
1467 }
1468
1469 pr_abort_t udp_abort;                   /* shared with udp6_usrreq.c */
1470 void
1471 udp_abort(struct socket *so)
1472 {
1473         struct inpcb *inp;
1474         struct inpcbinfo *pcbinfo;
1475
1476         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1477         inp = sotoinpcb(so);
1478         KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1479         INP_WLOCK(inp);
1480         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1481                 INP_HASH_WLOCK(pcbinfo);
1482                 in_pcbdisconnect(inp);
1483                 inp->inp_laddr.s_addr = INADDR_ANY;
1484                 INP_HASH_WUNLOCK(pcbinfo);
1485                 soisdisconnected(so);
1486         }
1487         INP_WUNLOCK(inp);
1488 }
1489
1490 static int
1491 udp_attach(struct socket *so, int proto, struct thread *td)
1492 {
1493         static uint32_t udp_flowid;
1494         struct inpcb *inp;
1495         struct inpcbinfo *pcbinfo;
1496         int error;
1497
1498         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1499         inp = sotoinpcb(so);
1500         KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1501         error = soreserve(so, udp_sendspace, udp_recvspace);
1502         if (error)
1503                 return (error);
1504         error = in_pcballoc(so, pcbinfo);
1505         if (error)
1506                 return (error);
1507
1508         inp = sotoinpcb(so);
1509         inp->inp_ip_ttl = V_ip_defttl;
1510         inp->inp_flowid = atomic_fetchadd_int(&udp_flowid, 1);
1511         inp->inp_flowtype = M_HASHTYPE_OPAQUE;
1512
1513         error = udp_newudpcb(inp);
1514         if (error) {
1515                 in_pcbdetach(inp);
1516                 in_pcbfree(inp);
1517                 return (error);
1518         }
1519         INP_WUNLOCK(inp);
1520
1521         return (0);
1522 }
1523 #endif /* INET */
1524
1525 int
1526 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx)
1527 {
1528         struct inpcb *inp;
1529         struct udpcb *up;
1530
1531         KASSERT(so->so_type == SOCK_DGRAM,
1532             ("udp_set_kernel_tunneling: !dgram"));
1533         inp = sotoinpcb(so);
1534         KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL"));
1535         INP_WLOCK(inp);
1536         up = intoudpcb(inp);
1537         if ((f != NULL || i != NULL) && ((up->u_tun_func != NULL) ||
1538             (up->u_icmp_func != NULL))) {
1539                 INP_WUNLOCK(inp);
1540                 return (EBUSY);
1541         }
1542         up->u_tun_func = f;
1543         up->u_icmp_func = i;
1544         up->u_tun_ctx = ctx;
1545         INP_WUNLOCK(inp);
1546         return (0);
1547 }
1548
1549 #ifdef INET
1550 static int
1551 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1552 {
1553         struct inpcb *inp;
1554         struct inpcbinfo *pcbinfo;
1555         struct sockaddr_in *sinp;
1556         int error;
1557
1558         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1559         inp = sotoinpcb(so);
1560         KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1561
1562         sinp = (struct sockaddr_in *)nam;
1563         if (nam->sa_family != AF_INET) {
1564                 /*
1565                  * Preserve compatibility with old programs.
1566                  */
1567                 if (nam->sa_family != AF_UNSPEC ||
1568                     nam->sa_len < offsetof(struct sockaddr_in, sin_zero) ||
1569                     sinp->sin_addr.s_addr != INADDR_ANY)
1570                         return (EAFNOSUPPORT);
1571                 nam->sa_family = AF_INET;
1572         }
1573         if (nam->sa_len != sizeof(struct sockaddr_in))
1574                 return (EINVAL);
1575
1576         INP_WLOCK(inp);
1577         INP_HASH_WLOCK(pcbinfo);
1578         error = in_pcbbind(inp, nam, td->td_ucred);
1579         INP_HASH_WUNLOCK(pcbinfo);
1580         INP_WUNLOCK(inp);
1581         return (error);
1582 }
1583
1584 static void
1585 udp_close(struct socket *so)
1586 {
1587         struct inpcb *inp;
1588         struct inpcbinfo *pcbinfo;
1589
1590         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1591         inp = sotoinpcb(so);
1592         KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1593         INP_WLOCK(inp);
1594         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1595                 INP_HASH_WLOCK(pcbinfo);
1596                 in_pcbdisconnect(inp);
1597                 inp->inp_laddr.s_addr = INADDR_ANY;
1598                 INP_HASH_WUNLOCK(pcbinfo);
1599                 soisdisconnected(so);
1600         }
1601         INP_WUNLOCK(inp);
1602 }
1603
1604 static int
1605 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1606 {
1607         struct epoch_tracker et;
1608         struct inpcb *inp;
1609         struct inpcbinfo *pcbinfo;
1610         struct sockaddr_in *sin;
1611         int error;
1612
1613         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1614         inp = sotoinpcb(so);
1615         KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1616
1617         sin = (struct sockaddr_in *)nam;
1618         if (sin->sin_family != AF_INET)
1619                 return (EAFNOSUPPORT);
1620         if (sin->sin_len != sizeof(*sin))
1621                 return (EINVAL);
1622
1623         INP_WLOCK(inp);
1624         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1625                 INP_WUNLOCK(inp);
1626                 return (EISCONN);
1627         }
1628         error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1629         if (error != 0) {
1630                 INP_WUNLOCK(inp);
1631                 return (error);
1632         }
1633         NET_EPOCH_ENTER(et);
1634         INP_HASH_WLOCK(pcbinfo);
1635         error = in_pcbconnect(inp, nam, td->td_ucred, true);
1636         INP_HASH_WUNLOCK(pcbinfo);
1637         NET_EPOCH_EXIT(et);
1638         if (error == 0)
1639                 soisconnected(so);
1640         INP_WUNLOCK(inp);
1641         return (error);
1642 }
1643
1644 static void
1645 udp_detach(struct socket *so)
1646 {
1647         struct inpcb *inp;
1648         struct udpcb *up;
1649
1650         inp = sotoinpcb(so);
1651         KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1652         KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1653             ("udp_detach: not disconnected"));
1654         INP_WLOCK(inp);
1655         up = intoudpcb(inp);
1656         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1657         inp->inp_ppcb = NULL;
1658         in_pcbdetach(inp);
1659         in_pcbfree(inp);
1660         udp_discardcb(up);
1661 }
1662
1663 pr_disconnect_t udp_disconnect;         /* shared with udp6_usrreq.c */
1664 int
1665 udp_disconnect(struct socket *so)
1666 {
1667         struct inpcb *inp;
1668         struct inpcbinfo *pcbinfo;
1669
1670         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1671         inp = sotoinpcb(so);
1672         KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1673         INP_WLOCK(inp);
1674         if (inp->inp_faddr.s_addr == INADDR_ANY) {
1675                 INP_WUNLOCK(inp);
1676                 return (ENOTCONN);
1677         }
1678         INP_HASH_WLOCK(pcbinfo);
1679         in_pcbdisconnect(inp);
1680         inp->inp_laddr.s_addr = INADDR_ANY;
1681         INP_HASH_WUNLOCK(pcbinfo);
1682         SOCK_LOCK(so);
1683         so->so_state &= ~SS_ISCONNECTED;                /* XXX */
1684         SOCK_UNLOCK(so);
1685         INP_WUNLOCK(inp);
1686         return (0);
1687 }
1688
1689 pr_send_t udp_send;                     /* shared with udp6_usrreq.c */
1690 int
1691 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1692     struct mbuf *control, struct thread *td)
1693 {
1694         struct inpcb *inp;
1695         int error;
1696
1697         inp = sotoinpcb(so);
1698         KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1699
1700         if (addr != NULL) {
1701                 error = 0;
1702                 if (addr->sa_family != AF_INET)
1703                         error = EAFNOSUPPORT;
1704                 else if (addr->sa_len != sizeof(struct sockaddr_in))
1705                         error = EINVAL;
1706                 if (__predict_false(error != 0)) {
1707                         m_freem(control);
1708                         m_freem(m);
1709                         return (error);
1710                 }
1711         }
1712         return (udp_output(inp, m, addr, control, td, flags));
1713 }
1714 #endif /* INET */
1715
1716 int
1717 udp_shutdown(struct socket *so)
1718 {
1719         struct inpcb *inp;
1720
1721         inp = sotoinpcb(so);
1722         KASSERT(inp != NULL, ("udp_shutdown: inp == NULL"));
1723         INP_WLOCK(inp);
1724         socantsendmore(so);
1725         INP_WUNLOCK(inp);
1726         return (0);
1727 }
1728
1729 #ifdef INET
1730 #define UDP_PROTOSW                                                     \
1731         .pr_type =              SOCK_DGRAM,                             \
1732         .pr_flags =             PR_ATOMIC | PR_ADDR | PR_CAPATTACH,     \
1733         .pr_ctloutput =         udp_ctloutput,                          \
1734         .pr_abort =             udp_abort,                              \
1735         .pr_attach =            udp_attach,                             \
1736         .pr_bind =              udp_bind,                               \
1737         .pr_connect =           udp_connect,                            \
1738         .pr_control =           in_control,                             \
1739         .pr_detach =            udp_detach,                             \
1740         .pr_disconnect =        udp_disconnect,                         \
1741         .pr_peeraddr =          in_getpeeraddr,                         \
1742         .pr_send =              udp_send,                               \
1743         .pr_soreceive =         soreceive_dgram,                        \
1744         .pr_sosend =            sosend_dgram,                           \
1745         .pr_shutdown =          udp_shutdown,                           \
1746         .pr_sockaddr =          in_getsockaddr,                         \
1747         .pr_sosetlabel =        in_pcbsosetlabel,                       \
1748         .pr_close =             udp_close
1749
1750 struct protosw udp_protosw = {
1751         .pr_protocol =          IPPROTO_UDP,
1752         UDP_PROTOSW
1753 };
1754
1755 struct protosw udplite_protosw = {
1756         .pr_protocol =          IPPROTO_UDPLITE,
1757         UDP_PROTOSW
1758 };
1759
1760 static void
1761 udp_init(void *arg __unused)
1762 {
1763
1764         IPPROTO_REGISTER(IPPROTO_UDP, udp_input, udp_ctlinput);
1765         IPPROTO_REGISTER(IPPROTO_UDPLITE, udp_input, udplite_ctlinput);
1766 }
1767 SYSINIT(udp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, udp_init, NULL);
1768 #endif /* INET */