sys/netinet6/udp6_usrreq.c

   1 /*-
   2  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   3  * Copyright (c) 2010-2011 Juniper Networks, Inc.
   4  * Copyright (c) 2014 Kevin Lo
   5  * All rights reserved.
   6  *
   7  * Portions of this software were developed by Robert N. M. Watson under
   8  * contract to Juniper Networks, Inc.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the project nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  *      $KAME: udp6_usrreq.c,v 1.27 2001/05/21 05:45:10 jinmei Exp $
  35  *      $KAME: udp6_output.c,v 1.31 2001/05/21 16:39:15 jinmei Exp $
  36  */
  37
  38 /*-
  39  * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
  40  *      The Regents of the University of California.
  41  * All rights reserved.
  42  *
  43  * Redistribution and use in source and binary forms, with or without
  44  * modification, are permitted provided that the following conditions
  45  * are met:
  46  * 1. Redistributions of source code must retain the above copyright
  47  *    notice, this list of conditions and the following disclaimer.
  48  * 2. Redistributions in binary form must reproduce the above copyright
  49  *    notice, this list of conditions and the following disclaimer in the
  50  *    documentation and/or other materials provided with the distribution.
  51  * 4. Neither the name of the University nor the names of its contributors
  52  *    may be used to endorse or promote products derived from this software
  53  *    without specific prior written permission.
  54  *
  55  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  56  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  57  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  58  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  59  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  60  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  61  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  62  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  63  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  64  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  65  * SUCH DAMAGE.
  66  *
  67  *      @(#)udp_usrreq.c        8.6 (Berkeley) 5/23/95
  68  */
  69
  70 #include <sys/cdefs.h>
  71 __FBSDID("$FreeBSD$");
  72
  73 #include "opt_inet.h"
  74 #include "opt_inet6.h"
  75 #include "opt_ipfw.h"
  76 #include "opt_ipsec.h"
  77 #include "opt_rss.h"
  78
  79 #include <sys/param.h>
  80 #include <sys/jail.h>
  81 #include <sys/kernel.h>
  82 #include <sys/lock.h>
  83 #include <sys/mbuf.h>
  84 #include <sys/priv.h>
  85 #include <sys/proc.h>
  86 #include <sys/protosw.h>
  87 #include <sys/sdt.h>
  88 #include <sys/signalvar.h>
  89 #include <sys/socket.h>
  90 #include <sys/socketvar.h>
  91 #include <sys/sx.h>
  92 #include <sys/sysctl.h>
  93 #include <sys/syslog.h>
  94 #include <sys/systm.h>
  95
  96 #include <net/if.h>
  97 #include <net/if_var.h>
  98 #include <net/if_types.h>
  99 #include <net/route.h>
 100 #include <net/rss_config.h>
 101
 102 #include <netinet/in.h>
 103 #include <netinet/in_kdtrace.h>
 104 #include <netinet/in_pcb.h>
 105 #include <netinet/in_systm.h>
 106 #include <netinet/in_var.h>
 107 #include <netinet/ip.h>
 108 #include <netinet/ip_icmp.h>
 109 #include <netinet/ip6.h>
 110 #include <netinet/icmp_var.h>
 111 #include <netinet/icmp6.h>
 112 #include <netinet/ip_var.h>
 113 #include <netinet/udp.h>
 114 #include <netinet/udp_var.h>
 115 #include <netinet/udplite.h>
 116
 117 #include <netinet6/ip6protosw.h>
 118 #include <netinet6/ip6_var.h>
 119 #include <netinet6/in6_pcb.h>
 120 #include <netinet6/in6_rss.h>
 121 #include <netinet6/udp6_var.h>
 122 #include <netinet6/scope6_var.h>
 123
 124 #ifdef IPSEC
 125 #include <netipsec/ipsec.h>
 126 #include <netipsec/ipsec6.h>
 127 #endif /* IPSEC */
 128
 129 #include <security/mac/mac_framework.h>
 130
 131 /*
 132  * UDP protocol implementation.
 133  * Per RFC 768, August, 1980.
 134  */
 135
 136 extern struct protosw   inetsw[];
 137 static void             udp6_detach(struct socket *so);
 138
 139 static int
 140 udp6_append(struct inpcb *inp, struct mbuf *n, int off,
 141     struct sockaddr_in6 *fromsa)
 142 {
 143         struct socket *so;
 144         struct mbuf *opts;
 145         struct udpcb *up;
 146
 147         INP_LOCK_ASSERT(inp);
 148
 149         /*
 150          * Engage the tunneling protocol.
 151          */
 152         up = intoudpcb(inp);
 153         if (up->u_tun_func != NULL) {
 154                 in_pcbref(inp);
 155                 INP_RUNLOCK(inp);
 156                 (*up->u_tun_func)(n, off, inp, (struct sockaddr *)fromsa,
 157                     up->u_tun_ctx);
 158                 INP_RLOCK(inp);
 159                 return (in_pcbrele_rlocked(inp));
 160         }
 161 #ifdef IPSEC
 162         /* Check AH/ESP integrity. */
 163         if (ipsec6_in_reject(n, inp)) {
 164                 m_freem(n);
 165                 return (0);
 166         }
 167 #endif /* IPSEC */
 168 #ifdef MAC
 169         if (mac_inpcb_check_deliver(inp, n) != 0) {
 170                 m_freem(n);
 171                 return (0);
 172         }
 173 #endif
 174         opts = NULL;
 175         if (inp->inp_flags & INP_CONTROLOPTS ||
 176             inp->inp_socket->so_options & SO_TIMESTAMP)
 177                 ip6_savecontrol(inp, n, &opts);
 178         m_adj(n, off + sizeof(struct udphdr));
 179
 180         so = inp->inp_socket;
 181         SOCKBUF_LOCK(&so->so_rcv);
 182         if (sbappendaddr_locked(&so->so_rcv, (struct sockaddr *)fromsa, n,
 183             opts) == 0) {
 184                 SOCKBUF_UNLOCK(&so->so_rcv);
 185                 m_freem(n);
 186                 if (opts)
 187                         m_freem(opts);
 188                 UDPSTAT_INC(udps_fullsock);
 189         } else
 190                 sorwakeup_locked(so);
 191         return (0);
 192 }
 193
 194 int
 195 udp6_input(struct mbuf **mp, int *offp, int proto)
 196 {
 197         struct mbuf *m = *mp;
 198         struct ifnet *ifp;
 199         struct ip6_hdr *ip6;
 200         struct udphdr *uh;
 201         struct inpcb *inp;
 202         struct inpcbinfo *pcbinfo;
 203         struct udpcb *up;
 204         int off = *offp;
 205         int cscov_partial;
 206         int plen, ulen;
 207         struct sockaddr_in6 fromsa;
 208         struct m_tag *fwd_tag;
 209         uint16_t uh_sum;
 210         uint8_t nxt;
 211
 212         ifp = m->m_pkthdr.rcvif;
 213         ip6 = mtod(m, struct ip6_hdr *);
 214
 215 #ifndef PULLDOWN_TEST
 216         IP6_EXTHDR_CHECK(m, off, sizeof(struct udphdr), IPPROTO_DONE);
 217         ip6 = mtod(m, struct ip6_hdr *);
 218         uh = (struct udphdr *)((caddr_t)ip6 + off);
 219 #else
 220         IP6_EXTHDR_GET(uh, struct udphdr *, m, off, sizeof(*uh));
 221         if (!uh)
 222                 return (IPPROTO_DONE);
 223 #endif
 224
 225         UDPSTAT_INC(udps_ipackets);
 226
 227         /*
 228          * Destination port of 0 is illegal, based on RFC768.
 229          */
 230         if (uh->uh_dport == 0)
 231                 goto badunlocked;
 232
 233         plen = ntohs(ip6->ip6_plen) - off + sizeof(*ip6);
 234         ulen = ntohs((u_short)uh->uh_ulen);
 235
 236         nxt = proto;
 237         cscov_partial = (nxt == IPPROTO_UDPLITE) ? 1 : 0;
 238         if (nxt == IPPROTO_UDPLITE) {
 239                 /* Zero means checksum over the complete packet. */
 240                 if (ulen == 0)
 241                         ulen = plen;
 242                 if (ulen == plen)
 243                         cscov_partial = 0;
 244                 if ((ulen < sizeof(struct udphdr)) || (ulen > plen)) {
 245                         /* XXX: What is the right UDPLite MIB counter? */
 246                         goto badunlocked;
 247                 }
 248                 if (uh->uh_sum == 0) {
 249                         /* XXX: What is the right UDPLite MIB counter? */
 250                         goto badunlocked;
 251                 }
 252         } else {
 253                 if ((ulen < sizeof(struct udphdr)) || (plen != ulen)) {
 254                         UDPSTAT_INC(udps_badlen);
 255                         goto badunlocked;
 256                 }
 257                 if (uh->uh_sum == 0) {
 258                         UDPSTAT_INC(udps_nosum);
 259                         goto badunlocked;
 260                 }
 261         }
 262
 263         if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID_IPV6) &&
 264             !cscov_partial) {
 265                 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
 266                         uh_sum = m->m_pkthdr.csum_data;
 267                 else
 268                         uh_sum = in6_cksum_pseudo(ip6, ulen, nxt,
 269                             m->m_pkthdr.csum_data);
 270                 uh_sum ^= 0xffff;
 271         } else
 272                 uh_sum = in6_cksum_partial(m, nxt, off, plen, ulen);
 273
 274         if (uh_sum != 0) {
 275                 UDPSTAT_INC(udps_badsum);
 276                 goto badunlocked;
 277         }
 278
 279         /*
 280          * Construct sockaddr format source address.
 281          */
 282         init_sin6(&fromsa, m);
 283         fromsa.sin6_port = uh->uh_sport;
 284
 285         pcbinfo = udp_get_inpcbinfo(nxt);
 286         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 287                 struct inpcb *last;
 288                 struct inpcbhead *pcblist;
 289                 struct ip6_moptions *imo;
 290
 291                 INP_INFO_RLOCK(pcbinfo);
 292                 /*
 293                  * In the event that laddr should be set to the link-local
 294                  * address (this happens in RIPng), the multicast address
 295                  * specified in the received packet will not match laddr.  To
 296                  * handle this situation, matching is relaxed if the
 297                  * receiving interface is the same as one specified in the
 298                  * socket and if the destination multicast address matches
 299                  * one of the multicast groups specified in the socket.
 300                  */
 301
 302                 /*
 303                  * KAME note: traditionally we dropped udpiphdr from mbuf
 304                  * here.  We need udphdr for IPsec processing so we do that
 305                  * later.
 306                  */
 307                 pcblist = udp_get_pcblist(nxt);
 308                 last = NULL;
 309                 LIST_FOREACH(inp, pcblist, inp_list) {
 310                         if ((inp->inp_vflag & INP_IPV6) == 0)
 311                                 continue;
 312                         if (inp->inp_lport != uh->uh_dport)
 313                                 continue;
 314                         if (inp->inp_fport != 0 &&
 315                             inp->inp_fport != uh->uh_sport)
 316                                 continue;
 317                         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
 318                                 if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr,
 319                                                         &ip6->ip6_dst))
 320                                         continue;
 321                         }
 322                         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 323                                 if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr,
 324                                                         &ip6->ip6_src) ||
 325                                     inp->inp_fport != uh->uh_sport)
 326                                         continue;
 327                         }
 328
 329                         /*
 330                          * XXXRW: Because we weren't holding either the inpcb
 331                          * or the hash lock when we checked for a match
 332                          * before, we should probably recheck now that the
 333                          * inpcb lock is (supposed to be) held.
 334                          */
 335
 336                         /*
 337                          * Handle socket delivery policy for any-source
 338                          * and source-specific multicast. [RFC3678]
 339                          */
 340                         imo = inp->in6p_moptions;
 341                         if (imo && IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 342                                 struct sockaddr_in6      mcaddr;
 343                                 int                      blocked;
 344
 345                                 INP_RLOCK(inp);
 346
 347                                 bzero(&mcaddr, sizeof(struct sockaddr_in6));
 348                                 mcaddr.sin6_len = sizeof(struct sockaddr_in6);
 349                                 mcaddr.sin6_family = AF_INET6;
 350                                 mcaddr.sin6_addr = ip6->ip6_dst;
 351
 352                                 blocked = im6o_mc_filter(imo, ifp,
 353                                         (struct sockaddr *)&mcaddr,
 354                                         (struct sockaddr *)&fromsa);
 355                                 if (blocked != MCAST_PASS) {
 356                                         if (blocked == MCAST_NOTGMEMBER)
 357                                                 IP6STAT_INC(ip6s_notmember);
 358                                         if (blocked == MCAST_NOTSMEMBER ||
 359                                             blocked == MCAST_MUTED)
 360                                                 UDPSTAT_INC(udps_filtermcast);
 361                                         INP_RUNLOCK(inp); /* XXX */
 362                                         continue;
 363                                 }
 364
 365                                 INP_RUNLOCK(inp);
 366                         }
 367                         if (last != NULL) {
 368                                 struct mbuf *n;
 369
 370                                 if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
 371                                         INP_RLOCK(last);
 372                                         UDP_PROBE(receive, NULL, last, ip6,
 373                                             last, uh);
 374                                         if (udp6_append(last, n, off, &fromsa))
 375                                                 goto inp_lost;
 376                                         INP_RUNLOCK(last);
 377                                 }
 378                         }
 379                         last = inp;
 380                         /*
 381                          * Don't look for additional matches if this one does
 382                          * not have either the SO_REUSEPORT or SO_REUSEADDR
 383                          * socket options set.  This heuristic avoids
 384                          * searching through all pcbs in the common case of a
 385                          * non-shared port.  It assumes that an application
 386                          * will never clear these options after setting them.
 387                          */
 388                         if ((last->inp_socket->so_options &
 389                              (SO_REUSEPORT|SO_REUSEADDR)) == 0)
 390                                 break;
 391                 }
 392
 393                 if (last == NULL) {
 394                         /*
 395                          * No matching pcb found; discard datagram.  (No need
 396                          * to send an ICMP Port Unreachable for a broadcast
 397                          * or multicast datgram.)
 398                          */
 399                         UDPSTAT_INC(udps_noport);
 400                         UDPSTAT_INC(udps_noportmcast);
 401                         goto badheadlocked;
 402                 }
 403                 INP_RLOCK(last);
 404                 INP_INFO_RUNLOCK(pcbinfo);
 405                 UDP_PROBE(receive, NULL, last, ip6, last, uh);
 406                 if (udp6_append(last, m, off, &fromsa) == 0)
 407                         INP_RUNLOCK(last);
 408         inp_lost:
 409                 return (IPPROTO_DONE);
 410         }
 411         /*
 412          * Locate pcb for datagram.
 413          */
 414
 415         /*
 416          * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
 417          */
 418         if ((m->m_flags & M_IP6_NEXTHOP) &&
 419             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 420                 struct sockaddr_in6 *next_hop6;
 421
 422                 next_hop6 = (struct sockaddr_in6 *)(fwd_tag + 1);
 423
 424                 /*
 425                  * Transparently forwarded. Pretend to be the destination.
 426                  * Already got one like this?
 427                  */
 428                 inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_src,
 429                     uh->uh_sport, &ip6->ip6_dst, uh->uh_dport,
 430                     INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif, m);
 431                 if (!inp) {
 432                         /*
 433                          * It's new.  Try to find the ambushing socket.
 434                          * Because we've rewritten the destination address,
 435                          * any hardware-generated hash is ignored.
 436                          */
 437                         inp = in6_pcblookup(pcbinfo, &ip6->ip6_src,
 438                             uh->uh_sport, &next_hop6->sin6_addr,
 439                             next_hop6->sin6_port ? htons(next_hop6->sin6_port) :
 440                             uh->uh_dport, INPLOOKUP_WILDCARD |
 441                             INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif);
 442                 }
 443                 /* Remove the tag from the packet. We don't need it anymore. */
 444                 m_tag_delete(m, fwd_tag);
 445                 m->m_flags &= ~M_IP6_NEXTHOP;
 446         } else
 447                 inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_src,
 448                     uh->uh_sport, &ip6->ip6_dst, uh->uh_dport,
 449                     INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB,
 450                     m->m_pkthdr.rcvif, m);
 451         if (inp == NULL) {
 452                 if (udp_log_in_vain) {
 453                         char ip6bufs[INET6_ADDRSTRLEN];
 454                         char ip6bufd[INET6_ADDRSTRLEN];
 455
 456                         log(LOG_INFO,
 457                             "Connection attempt to UDP [%s]:%d from [%s]:%d\n",
 458                             ip6_sprintf(ip6bufd, &ip6->ip6_dst),
 459                             ntohs(uh->uh_dport),
 460                             ip6_sprintf(ip6bufs, &ip6->ip6_src),
 461                             ntohs(uh->uh_sport));
 462                 }
 463                 UDPSTAT_INC(udps_noport);
 464                 if (m->m_flags & M_MCAST) {
 465                         printf("UDP6: M_MCAST is set in a unicast packet.\n");
 466                         UDPSTAT_INC(udps_noportmcast);
 467                         goto badunlocked;
 468                 }
 469                 if (V_udp_blackhole)
 470                         goto badunlocked;
 471                 if (badport_bandlim(BANDLIM_ICMP6_UNREACH) < 0)
 472                         goto badunlocked;
 473                 icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
 474                 return (IPPROTO_DONE);
 475         }
 476         INP_RLOCK_ASSERT(inp);
 477         up = intoudpcb(inp);
 478         if (cscov_partial) {
 479                 if (up->u_rxcslen == 0 || up->u_rxcslen > ulen) {
 480                         INP_RUNLOCK(inp);
 481                         m_freem(m);
 482                         return (IPPROTO_DONE);
 483                 }
 484         }
 485         UDP_PROBE(receive, NULL, inp, ip6, inp, uh);
 486         if (udp6_append(inp, m, off, &fromsa) == 0)
 487                 INP_RUNLOCK(inp);
 488         return (IPPROTO_DONE);
 489
 490 badheadlocked:
 491         INP_INFO_RUNLOCK(pcbinfo);
 492 badunlocked:
 493         if (m)
 494                 m_freem(m);
 495         return (IPPROTO_DONE);
 496 }
 497
 498 static void
 499 udp6_common_ctlinput(int cmd, struct sockaddr *sa, void *d,
 500     struct inpcbinfo *pcbinfo)
 501 {
 502         struct udphdr uh;
 503         struct ip6_hdr *ip6;
 504         struct mbuf *m;
 505         int off = 0;
 506         struct ip6ctlparam *ip6cp = NULL;
 507         const struct sockaddr_in6 *sa6_src = NULL;
 508         void *cmdarg;
 509         struct inpcb *(*notify)(struct inpcb *, int) = udp_notify;
 510         struct udp_portonly {
 511                 u_int16_t uh_sport;
 512                 u_int16_t uh_dport;
 513         } *uhp;
 514
 515         if (sa->sa_family != AF_INET6 ||
 516             sa->sa_len != sizeof(struct sockaddr_in6))
 517                 return;
 518
 519         if ((unsigned)cmd >= PRC_NCMDS)
 520                 return;
 521         if (PRC_IS_REDIRECT(cmd))
 522                 notify = in6_rtchange, d = NULL;
 523         else if (cmd == PRC_HOSTDEAD)
 524                 d = NULL;
 525         else if (inet6ctlerrmap[cmd] == 0)
 526                 return;
 527
 528         /* if the parameter is from icmp6, decode it. */
 529         if (d != NULL) {
 530                 ip6cp = (struct ip6ctlparam *)d;
 531                 m = ip6cp->ip6c_m;
 532                 ip6 = ip6cp->ip6c_ip6;
 533                 off = ip6cp->ip6c_off;
 534                 cmdarg = ip6cp->ip6c_cmdarg;
 535                 sa6_src = ip6cp->ip6c_src;
 536         } else {
 537                 m = NULL;
 538                 ip6 = NULL;
 539                 cmdarg = NULL;
 540                 sa6_src = &sa6_any;
 541         }
 542
 543         if (ip6) {
 544                 /*
 545                  * XXX: We assume that when IPV6 is non NULL,
 546                  * M and OFF are valid.
 547                  */
 548
 549                 /* Check if we can safely examine src and dst ports. */
 550                 if (m->m_pkthdr.len < off + sizeof(*uhp))
 551                         return;
 552
 553                 bzero(&uh, sizeof(uh));
 554                 m_copydata(m, off, sizeof(*uhp), (caddr_t)&uh);
 555
 556                 (void)in6_pcbnotify(pcbinfo, sa, uh.uh_dport,
 557                     (struct sockaddr *)ip6cp->ip6c_src, uh.uh_sport, cmd,
 558                     cmdarg, notify);
 559         } else
 560                 (void)in6_pcbnotify(pcbinfo, sa, 0,
 561                     (const struct sockaddr *)sa6_src, 0, cmd, cmdarg, notify);
 562 }
 563
 564 void
 565 udp6_ctlinput(int cmd, struct sockaddr *sa, void *d)
 566 {
 567
 568         return (udp6_common_ctlinput(cmd, sa, d, &V_udbinfo));
 569 }
 570
 571 void
 572 udplite6_ctlinput(int cmd, struct sockaddr *sa, void *d)
 573 {
 574
 575         return (udp6_common_ctlinput(cmd, sa, d, &V_ulitecbinfo));
 576 }
 577
 578 static int
 579 udp6_getcred(SYSCTL_HANDLER_ARGS)
 580 {
 581         struct xucred xuc;
 582         struct sockaddr_in6 addrs[2];
 583         struct inpcb *inp;
 584         int error;
 585
 586         error = priv_check(req->td, PRIV_NETINET_GETCRED);
 587         if (error)
 588                 return (error);
 589
 590         if (req->newlen != sizeof(addrs))
 591                 return (EINVAL);
 592         if (req->oldlen != sizeof(struct xucred))
 593                 return (EINVAL);
 594         error = SYSCTL_IN(req, addrs, sizeof(addrs));
 595         if (error)
 596                 return (error);
 597         if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 ||
 598             (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) {
 599                 return (error);
 600         }
 601         inp = in6_pcblookup(&V_udbinfo, &addrs[1].sin6_addr,
 602             addrs[1].sin6_port, &addrs[0].sin6_addr, addrs[0].sin6_port,
 603             INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 604         if (inp != NULL) {
 605                 INP_RLOCK_ASSERT(inp);
 606                 if (inp->inp_socket == NULL)
 607                         error = ENOENT;
 608                 if (error == 0)
 609                         error = cr_canseesocket(req->td->td_ucred,
 610                             inp->inp_socket);
 611                 if (error == 0)
 612                         cru2x(inp->inp_cred, &xuc);
 613                 INP_RUNLOCK(inp);
 614         } else
 615                 error = ENOENT;
 616         if (error == 0)
 617                 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
 618         return (error);
 619 }
 620
 621 SYSCTL_PROC(_net_inet6_udp6, OID_AUTO, getcred, CTLTYPE_OPAQUE|CTLFLAG_RW, 0,
 622     0, udp6_getcred, "S,xucred", "Get the xucred of a UDP6 connection");
 623
 624 static int
 625 udp6_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr6,
 626     struct mbuf *control, struct thread *td)
 627 {
 628         u_int32_t ulen = m->m_pkthdr.len;
 629         u_int32_t plen = sizeof(struct udphdr) + ulen;
 630         struct ip6_hdr *ip6;
 631         struct udphdr *udp6;
 632         struct in6_addr *laddr, *faddr, in6a;
 633         struct sockaddr_in6 *sin6 = NULL;
 634         int cscov_partial = 0;
 635         int scope_ambiguous = 0;
 636         u_short fport;
 637         int error = 0;
 638         uint8_t nxt;
 639         uint16_t cscov = 0;
 640         struct ip6_pktopts *optp, opt;
 641         int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
 642         int flags;
 643         struct sockaddr_in6 tmp;
 644
 645         INP_WLOCK_ASSERT(inp);
 646         INP_HASH_WLOCK_ASSERT(inp->inp_pcbinfo);
 647
 648         if (addr6) {
 649                 /* addr6 has been validated in udp6_send(). */
 650                 sin6 = (struct sockaddr_in6 *)addr6;
 651
 652                 /* protect *sin6 from overwrites */
 653                 tmp = *sin6;
 654                 sin6 = &tmp;
 655
 656                 /*
 657                  * Application should provide a proper zone ID or the use of
 658                  * default zone IDs should be enabled.  Unfortunately, some
 659                  * applications do not behave as it should, so we need a
 660                  * workaround.  Even if an appropriate ID is not determined,
 661                  * we'll see if we can determine the outgoing interface.  If we
 662                  * can, determine the zone ID based on the interface below.
 663                  */
 664                 if (sin6->sin6_scope_id == 0 && !V_ip6_use_defzone)
 665                         scope_ambiguous = 1;
 666                 if ((error = sa6_embedscope(sin6, V_ip6_use_defzone)) != 0)
 667                         return (error);
 668         }
 669
 670         nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
 671             IPPROTO_UDP : IPPROTO_UDPLITE;
 672         if (control) {
 673                 if ((error = ip6_setpktopts(control, &opt,
 674                     inp->in6p_outputopts, td->td_ucred, nxt)) != 0)
 675                         goto release;
 676                 optp = &opt;
 677         } else
 678                 optp = inp->in6p_outputopts;
 679
 680         if (sin6) {
 681                 faddr = &sin6->sin6_addr;
 682
 683                 /*
 684                  * Since we saw no essential reason for calling in_pcbconnect,
 685                  * we get rid of such kind of logic, and call in6_selectsrc
 686                  * and in6_pcbsetport in order to fill in the local address
 687                  * and the local port.
 688                  */
 689                 if (sin6->sin6_port == 0) {
 690                         error = EADDRNOTAVAIL;
 691                         goto release;
 692                 }
 693
 694                 if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 695                         /* how about ::ffff:0.0.0.0 case? */
 696                         error = EISCONN;
 697                         goto release;
 698                 }
 699
 700                 fport = sin6->sin6_port; /* allow 0 port */
 701
 702                 if (IN6_IS_ADDR_V4MAPPED(faddr)) {
 703                         if ((inp->inp_flags & IN6P_IPV6_V6ONLY)) {
 704                                 /*
 705                                  * I believe we should explicitly discard the
 706                                  * packet when mapped addresses are disabled,
 707                                  * rather than send the packet as an IPv6 one.
 708                                  * If we chose the latter approach, the packet
 709                                  * might be sent out on the wire based on the
 710                                  * default route, the situation which we'd
 711                                  * probably want to avoid.
 712                                  * (20010421 jinmei@kame.net)
 713                                  */
 714                                 error = EINVAL;
 715                                 goto release;
 716                         }
 717                         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
 718                             !IN6_IS_ADDR_V4MAPPED(&inp->in6p_laddr)) {
 719                                 /*
 720                                  * when remote addr is an IPv4-mapped address,
 721                                  * local addr should not be an IPv6 address,
 722                                  * since you cannot determine how to map IPv6
 723                                  * source address to IPv4.
 724                                  */
 725                                 error = EINVAL;
 726                                 goto release;
 727                         }
 728
 729                         af = AF_INET;
 730                 }
 731
 732                 if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
 733                         error = in6_selectsrc_socket(sin6, optp, inp,
 734                             td->td_ucred, scope_ambiguous, &in6a, NULL);
 735                         if (error)
 736                                 goto release;
 737                         laddr = &in6a;
 738                 } else
 739                         laddr = &inp->in6p_laddr;       /* XXX */
 740                 if (laddr == NULL) {
 741                         if (error == 0)
 742                                 error = EADDRNOTAVAIL;
 743                         goto release;
 744                 }
 745                 if (inp->inp_lport == 0 &&
 746                     (error = in6_pcbsetport(laddr, inp, td->td_ucred)) != 0) {
 747                         /* Undo an address bind that may have occurred. */
 748                         inp->in6p_laddr = in6addr_any;
 749                         goto release;
 750                 }
 751         } else {
 752                 if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 753                         error = ENOTCONN;
 754                         goto release;
 755                 }
 756                 if (IN6_IS_ADDR_V4MAPPED(&inp->in6p_faddr)) {
 757                         if ((inp->inp_flags & IN6P_IPV6_V6ONLY)) {
 758                                 /*
 759                                  * XXX: this case would happen when the
 760                                  * application sets the V6ONLY flag after
 761                                  * connecting the foreign address.
 762                                  * Such applications should be fixed,
 763                                  * so we bark here.
 764                                  */
 765                                 log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
 766                                     "option was set for a connected socket\n");
 767                                 error = EINVAL;
 768                                 goto release;
 769                         } else
 770                                 af = AF_INET;
 771                 }
 772                 laddr = &inp->in6p_laddr;
 773                 faddr = &inp->in6p_faddr;
 774                 fport = inp->inp_fport;
 775         }
 776
 777         if (af == AF_INET)
 778                 hlen = sizeof(struct ip);
 779
 780         /*
 781          * Calculate data length and get a mbuf
 782          * for UDP and IP6 headers.
 783          */
 784         M_PREPEND(m, hlen + sizeof(struct udphdr), M_NOWAIT);
 785         if (m == NULL) {
 786                 error = ENOBUFS;
 787                 goto release;
 788         }
 789
 790         /*
 791          * Stuff checksum and output datagram.
 792          */
 793         udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
 794         udp6->uh_sport = inp->inp_lport; /* lport is always set in the PCB */
 795         udp6->uh_dport = fport;
 796         if (nxt == IPPROTO_UDPLITE) {
 797                 struct udpcb *up;
 798
 799                 up = intoudpcb(inp);
 800                 cscov = up->u_txcslen;
 801                 if (cscov >= plen)
 802                         cscov = 0;
 803                 udp6->uh_ulen = htons(cscov);
 804                 /*
 805                  * For UDP-Lite, checksum coverage length of zero means
 806                  * the entire UDPLite packet is covered by the checksum.
 807                  */
 808                 cscov_partial = (cscov == 0) ? 0 : 1;
 809         } else if (plen <= 0xffff)
 810                 udp6->uh_ulen = htons((u_short)plen);
 811         else
 812                 udp6->uh_ulen = 0;
 813         udp6->uh_sum = 0;
 814
 815         switch (af) {
 816         case AF_INET6:
 817                 ip6 = mtod(m, struct ip6_hdr *);
 818                 ip6->ip6_flow   = inp->inp_flow & IPV6_FLOWINFO_MASK;
 819                 ip6->ip6_vfc    &= ~IPV6_VERSION_MASK;
 820                 ip6->ip6_vfc    |= IPV6_VERSION;
 821                 ip6->ip6_plen   = htons((u_short)plen);
 822                 ip6->ip6_nxt    = nxt;
 823                 ip6->ip6_hlim   = in6_selecthlim(inp, NULL);
 824                 ip6->ip6_src    = *laddr;
 825                 ip6->ip6_dst    = *faddr;
 826
 827                 if (cscov_partial) {
 828                         if ((udp6->uh_sum = in6_cksum_partial(m, nxt,
 829                             sizeof(struct ip6_hdr), plen, cscov)) == 0)
 830                                 udp6->uh_sum = 0xffff;
 831                 } else {
 832                         udp6->uh_sum = in6_cksum_pseudo(ip6, plen, nxt, 0);
 833                         m->m_pkthdr.csum_flags = CSUM_UDP_IPV6;
 834                         m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
 835                 }
 836
 837 #ifdef  RSS
 838                 {
 839                         uint32_t hash_val, hash_type;
 840                         uint8_t pr;
 841
 842                         pr = inp->inp_socket->so_proto->pr_protocol;
 843                         /*
 844                          * Calculate an appropriate RSS hash for UDP and
 845                          * UDP Lite.
 846                          *
 847                          * The called function will take care of figuring out
 848                          * whether a 2-tuple or 4-tuple hash is required based
 849                          * on the currently configured scheme.
 850                          *
 851                          * Later later on connected socket values should be
 852                          * cached in the inpcb and reused, rather than constantly
 853                          * re-calculating it.
 854                          *
 855                          * UDP Lite is a different protocol number and will
 856                          * likely end up being hashed as a 2-tuple until
 857                          * RSS / NICs grow UDP Lite protocol awareness.
 858                          */
 859                         if (rss_proto_software_hash_v6(faddr, laddr, fport,
 860                             inp->inp_lport, pr, &hash_val, &hash_type) == 0) {
 861                                 m->m_pkthdr.flowid = hash_val;
 862                                 M_HASHTYPE_SET(m, hash_type);
 863                         }
 864                 }
 865 #endif
 866                 flags = 0;
 867 #ifdef  RSS
 868                 /*
 869                  * Don't override with the inp cached flowid.
 870                  *
 871                  * Until the whole UDP path is vetted, it may actually
 872                  * be incorrect.
 873                  */
 874                 flags |= IP_NODEFAULTFLOWID;
 875 #endif
 876
 877                 UDP_PROBE(send, NULL, inp, ip6, inp, udp6);
 878                 UDPSTAT_INC(udps_opackets);
 879                 error = ip6_output(m, optp, &inp->inp_route6, flags,
 880                     inp->in6p_moptions, NULL, inp);
 881                 break;
 882         case AF_INET:
 883                 error = EAFNOSUPPORT;
 884                 goto release;
 885         }
 886         goto releaseopt;
 887
 888 release:
 889         m_freem(m);
 890
 891 releaseopt:
 892         if (control) {
 893                 ip6_clearpktopts(&opt, -1);
 894                 m_freem(control);
 895         }
 896         return (error);
 897 }
 898
 899 static void
 900 udp6_abort(struct socket *so)
 901 {
 902         struct inpcb *inp;
 903         struct inpcbinfo *pcbinfo;
 904
 905         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
 906         inp = sotoinpcb(so);
 907         KASSERT(inp != NULL, ("udp6_abort: inp == NULL"));
 908
 909         INP_WLOCK(inp);
 910 #ifdef INET
 911         if (inp->inp_vflag & INP_IPV4) {
 912                 struct pr_usrreqs *pru;
 913                 uint8_t nxt;
 914
 915                 nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
 916                     IPPROTO_UDP : IPPROTO_UDPLITE;
 917                 INP_WUNLOCK(inp);
 918                 pru = inetsw[ip_protox[nxt]].pr_usrreqs;
 919                 (*pru->pru_abort)(so);
 920                 return;
 921         }
 922 #endif
 923
 924         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 925                 INP_HASH_WLOCK(pcbinfo);
 926                 in6_pcbdisconnect(inp);
 927                 inp->in6p_laddr = in6addr_any;
 928                 INP_HASH_WUNLOCK(pcbinfo);
 929                 soisdisconnected(so);
 930         }
 931         INP_WUNLOCK(inp);
 932 }
 933
 934 static int
 935 udp6_attach(struct socket *so, int proto, struct thread *td)
 936 {
 937         struct inpcb *inp;
 938         struct inpcbinfo *pcbinfo;
 939         int error;
 940
 941         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
 942         inp = sotoinpcb(so);
 943         KASSERT(inp == NULL, ("udp6_attach: inp != NULL"));
 944
 945         if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
 946                 error = soreserve(so, udp_sendspace, udp_recvspace);
 947                 if (error)
 948                         return (error);
 949         }
 950         INP_INFO_WLOCK(pcbinfo);
 951         error = in_pcballoc(so, pcbinfo);
 952         if (error) {
 953                 INP_INFO_WUNLOCK(pcbinfo);
 954                 return (error);
 955         }
 956         inp = (struct inpcb *)so->so_pcb;
 957         inp->inp_vflag |= INP_IPV6;
 958         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
 959                 inp->inp_vflag |= INP_IPV4;
 960         inp->in6p_hops = -1;    /* use kernel default */
 961         inp->in6p_cksum = -1;   /* just to be sure */
 962         /*
 963          * XXX: ugly!!
 964          * IPv4 TTL initialization is necessary for an IPv6 socket as well,
 965          * because the socket may be bound to an IPv6 wildcard address,
 966          * which may match an IPv4-mapped IPv6 address.
 967          */
 968         inp->inp_ip_ttl = V_ip_defttl;
 969
 970         error = udp_newudpcb(inp);
 971         if (error) {
 972                 in_pcbdetach(inp);
 973                 in_pcbfree(inp);
 974                 INP_INFO_WUNLOCK(pcbinfo);
 975                 return (error);
 976         }
 977         INP_WUNLOCK(inp);
 978         INP_INFO_WUNLOCK(pcbinfo);
 979         return (0);
 980 }
 981
 982 static int
 983 udp6_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
 984 {
 985         struct inpcb *inp;
 986         struct inpcbinfo *pcbinfo;
 987         int error;
 988
 989         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
 990         inp = sotoinpcb(so);
 991         KASSERT(inp != NULL, ("udp6_bind: inp == NULL"));
 992
 993         INP_WLOCK(inp);
 994         INP_HASH_WLOCK(pcbinfo);
 995         inp->inp_vflag &= ~INP_IPV4;
 996         inp->inp_vflag |= INP_IPV6;
 997         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
 998                 struct sockaddr_in6 *sin6_p;
 999
1000                 sin6_p = (struct sockaddr_in6 *)nam;
1001
1002                 if (IN6_IS_ADDR_UNSPECIFIED(&sin6_p->sin6_addr))
1003                         inp->inp_vflag |= INP_IPV4;
1004 #ifdef INET
1005                 else if (IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {
1006                         struct sockaddr_in sin;
1007
1008                         in6_sin6_2_sin(&sin, sin6_p);
1009                         inp->inp_vflag |= INP_IPV4;
1010                         inp->inp_vflag &= ~INP_IPV6;
1011                         error = in_pcbbind(inp, (struct sockaddr *)&sin,
1012                             td->td_ucred);
1013                         goto out;
1014                 }
1015 #endif
1016         }
1017
1018         error = in6_pcbbind(inp, nam, td->td_ucred);
1019 #ifdef INET
1020 out:
1021 #endif
1022         INP_HASH_WUNLOCK(pcbinfo);
1023         INP_WUNLOCK(inp);
1024         return (error);
1025 }
1026
1027 static void
1028 udp6_close(struct socket *so)
1029 {
1030         struct inpcb *inp;
1031         struct inpcbinfo *pcbinfo;
1032
1033         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1034         inp = sotoinpcb(so);
1035         KASSERT(inp != NULL, ("udp6_close: inp == NULL"));
1036
1037         INP_WLOCK(inp);
1038 #ifdef INET
1039         if (inp->inp_vflag & INP_IPV4) {
1040                 struct pr_usrreqs *pru;
1041                 uint8_t nxt;
1042
1043                 nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
1044                     IPPROTO_UDP : IPPROTO_UDPLITE;
1045                 INP_WUNLOCK(inp);
1046                 pru = inetsw[ip_protox[nxt]].pr_usrreqs;
1047                 (*pru->pru_disconnect)(so);
1048                 return;
1049         }
1050 #endif
1051         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1052                 INP_HASH_WLOCK(pcbinfo);
1053                 in6_pcbdisconnect(inp);
1054                 inp->in6p_laddr = in6addr_any;
1055                 INP_HASH_WUNLOCK(pcbinfo);
1056                 soisdisconnected(so);
1057         }
1058         INP_WUNLOCK(inp);
1059 }
1060
1061 static int
1062 udp6_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1063 {
1064         struct inpcb *inp;
1065         struct inpcbinfo *pcbinfo;
1066         struct sockaddr_in6 *sin6;
1067         int error;
1068
1069         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1070         inp = sotoinpcb(so);
1071         sin6 = (struct sockaddr_in6 *)nam;
1072         KASSERT(inp != NULL, ("udp6_connect: inp == NULL"));
1073
1074         /*
1075          * XXXRW: Need to clarify locking of v4/v6 flags.
1076          */
1077         INP_WLOCK(inp);
1078 #ifdef INET
1079         if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
1080                 struct sockaddr_in sin;
1081
1082                 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
1083                         error = EINVAL;
1084                         goto out;
1085                 }
1086                 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1087                         error = EISCONN;
1088                         goto out;
1089                 }
1090                 in6_sin6_2_sin(&sin, sin6);
1091                 inp->inp_vflag |= INP_IPV4;
1092                 inp->inp_vflag &= ~INP_IPV6;
1093                 error = prison_remote_ip4(td->td_ucred, &sin.sin_addr);
1094                 if (error != 0)
1095                         goto out;
1096                 INP_HASH_WLOCK(pcbinfo);
1097                 error = in_pcbconnect(inp, (struct sockaddr *)&sin,
1098                     td->td_ucred);
1099                 INP_HASH_WUNLOCK(pcbinfo);
1100                 if (error == 0)
1101                         soisconnected(so);
1102                 goto out;
1103         }
1104 #endif
1105         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1106                 error = EISCONN;
1107                 goto out;
1108         }
1109         inp->inp_vflag &= ~INP_IPV4;
1110         inp->inp_vflag |= INP_IPV6;
1111         error = prison_remote_ip6(td->td_ucred, &sin6->sin6_addr);
1112         if (error != 0)
1113                 goto out;
1114         INP_HASH_WLOCK(pcbinfo);
1115         error = in6_pcbconnect(inp, nam, td->td_ucred);
1116         INP_HASH_WUNLOCK(pcbinfo);
1117         if (error == 0)
1118                 soisconnected(so);
1119 out:
1120         INP_WUNLOCK(inp);
1121         return (error);
1122 }
1123
1124 static void
1125 udp6_detach(struct socket *so)
1126 {
1127         struct inpcb *inp;
1128         struct inpcbinfo *pcbinfo;
1129         struct udpcb *up;
1130
1131         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1132         inp = sotoinpcb(so);
1133         KASSERT(inp != NULL, ("udp6_detach: inp == NULL"));
1134
1135         INP_INFO_WLOCK(pcbinfo);
1136         INP_WLOCK(inp);
1137         up = intoudpcb(inp);
1138         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1139         in_pcbdetach(inp);
1140         in_pcbfree(inp);
1141         INP_INFO_WUNLOCK(pcbinfo);
1142         udp_discardcb(up);
1143 }
1144
1145 static int
1146 udp6_disconnect(struct socket *so)
1147 {
1148         struct inpcb *inp;
1149         struct inpcbinfo *pcbinfo;
1150         int error;
1151
1152         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1153         inp = sotoinpcb(so);
1154         KASSERT(inp != NULL, ("udp6_disconnect: inp == NULL"));
1155
1156         INP_WLOCK(inp);
1157 #ifdef INET
1158         if (inp->inp_vflag & INP_IPV4) {
1159                 struct pr_usrreqs *pru;
1160                 uint8_t nxt;
1161
1162                 nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
1163                     IPPROTO_UDP : IPPROTO_UDPLITE;
1164                 INP_WUNLOCK(inp);
1165                 pru = inetsw[ip_protox[nxt]].pr_usrreqs;
1166                 (void)(*pru->pru_disconnect)(so);
1167                 return (0);
1168         }
1169 #endif
1170
1171         if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1172                 error = ENOTCONN;
1173                 goto out;
1174         }
1175
1176         INP_HASH_WLOCK(pcbinfo);
1177         in6_pcbdisconnect(inp);
1178         inp->in6p_laddr = in6addr_any;
1179         INP_HASH_WUNLOCK(pcbinfo);
1180         SOCK_LOCK(so);
1181         so->so_state &= ~SS_ISCONNECTED;                /* XXX */
1182         SOCK_UNLOCK(so);
1183 out:
1184         INP_WUNLOCK(inp);
1185         return (0);
1186 }
1187
1188 static int
1189 udp6_send(struct socket *so, int flags, struct mbuf *m,
1190     struct sockaddr *addr, struct mbuf *control, struct thread *td)
1191 {
1192         struct inpcb *inp;
1193         struct inpcbinfo *pcbinfo;
1194         int error = 0;
1195
1196         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1197         inp = sotoinpcb(so);
1198         KASSERT(inp != NULL, ("udp6_send: inp == NULL"));
1199
1200         INP_WLOCK(inp);
1201         if (addr) {
1202                 if (addr->sa_len != sizeof(struct sockaddr_in6)) {
1203                         error = EINVAL;
1204                         goto bad;
1205                 }
1206                 if (addr->sa_family != AF_INET6) {
1207                         error = EAFNOSUPPORT;
1208                         goto bad;
1209                 }
1210         }
1211
1212 #ifdef INET
1213         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
1214                 int hasv4addr;
1215                 struct sockaddr_in6 *sin6 = NULL;
1216
1217                 if (addr == NULL)
1218                         hasv4addr = (inp->inp_vflag & INP_IPV4);
1219                 else {
1220                         sin6 = (struct sockaddr_in6 *)addr;
1221                         hasv4addr = IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)
1222                             ? 1 : 0;
1223                 }
1224                 if (hasv4addr) {
1225                         struct pr_usrreqs *pru;
1226                         uint8_t nxt;
1227
1228                         nxt = (inp->inp_socket->so_proto->pr_protocol ==
1229                             IPPROTO_UDP) ? IPPROTO_UDP : IPPROTO_UDPLITE;
1230                         /*
1231                          * XXXRW: We release UDP-layer locks before calling
1232                          * udp_send() in order to avoid recursion.  However,
1233                          * this does mean there is a short window where inp's
1234                          * fields are unstable.  Could this lead to a
1235                          * potential race in which the factors causing us to
1236                          * select the UDPv4 output routine are invalidated?
1237                          */
1238                         INP_WUNLOCK(inp);
1239                         if (sin6)
1240                                 in6_sin6_2_sin_in_sock(addr);
1241                         pru = inetsw[ip_protox[nxt]].pr_usrreqs;
1242                         /* addr will just be freed in sendit(). */
1243                         return ((*pru->pru_send)(so, flags, m, addr, control,
1244                             td));
1245                 }
1246         }
1247 #endif
1248 #ifdef MAC
1249         mac_inpcb_create_mbuf(inp, m);
1250 #endif
1251         INP_HASH_WLOCK(pcbinfo);
1252         error = udp6_output(inp, m, addr, control, td);
1253         INP_HASH_WUNLOCK(pcbinfo);
1254         INP_WUNLOCK(inp);
1255         return (error);
1256
1257 bad:
1258         INP_WUNLOCK(inp);
1259         m_freem(m);
1260         return (error);
1261 }
1262
1263 struct pr_usrreqs udp6_usrreqs = {
1264         .pru_abort =            udp6_abort,
1265         .pru_attach =           udp6_attach,
1266         .pru_bind =             udp6_bind,
1267         .pru_connect =          udp6_connect,
1268         .pru_control =          in6_control,
1269         .pru_detach =           udp6_detach,
1270         .pru_disconnect =       udp6_disconnect,
1271         .pru_peeraddr =         in6_mapped_peeraddr,
1272         .pru_send =             udp6_send,
1273         .pru_shutdown =         udp_shutdown,
1274         .pru_sockaddr =         in6_mapped_sockaddr,
1275         .pru_soreceive =        soreceive_dgram,
1276         .pru_sosend =           sosend_dgram,
1277         .pru_sosetlabel =       in_pcbsosetlabel,
1278         .pru_close =            udp6_close
1279 };