sys/netinet6/udp6_usrreq.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   5  * Copyright (c) 2010-2011 Juniper Networks, Inc.
   6  * Copyright (c) 2014 Kevin Lo
   7  * All rights reserved.
   8  *
   9  * Portions of this software were developed by Robert N. M. Watson under
  10  * contract to Juniper Networks, Inc.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  * 2. Redistributions in binary form must reproduce the above copyright
  18  *    notice, this list of conditions and the following disclaimer in the
  19  *    documentation and/or other materials provided with the distribution.
  20  * 3. Neither the name of the project nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  *
  36  *      $KAME: udp6_usrreq.c,v 1.27 2001/05/21 05:45:10 jinmei Exp $
  37  *      $KAME: udp6_output.c,v 1.31 2001/05/21 16:39:15 jinmei Exp $
  38  */
  39
  40 /*-
  41  * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
  42  *      The Regents of the University of California.
  43  * All rights reserved.
  44  *
  45  * Redistribution and use in source and binary forms, with or without
  46  * modification, are permitted provided that the following conditions
  47  * are met:
  48  * 1. Redistributions of source code must retain the above copyright
  49  *    notice, this list of conditions and the following disclaimer.
  50  * 2. Redistributions in binary form must reproduce the above copyright
  51  *    notice, this list of conditions and the following disclaimer in the
  52  *    documentation and/or other materials provided with the distribution.
  53  * 3. Neither the name of the University nor the names of its contributors
  54  *    may be used to endorse or promote products derived from this software
  55  *    without specific prior written permission.
  56  *
  57  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  58  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  59  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  60  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  61  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  62  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  63  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  64  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  65  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  66  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  67  * SUCH DAMAGE.
  68  *
  69  *      @(#)udp_usrreq.c        8.6 (Berkeley) 5/23/95
  70  */
  71
  72 #include <sys/cdefs.h>
  73 __FBSDID("$FreeBSD$");
  74
  75 #include "opt_inet.h"
  76 #include "opt_inet6.h"
  77 #include "opt_ipsec.h"
  78 #include "opt_rss.h"
  79
  80 #include <sys/param.h>
  81 #include <sys/jail.h>
  82 #include <sys/kernel.h>
  83 #include <sys/lock.h>
  84 #include <sys/mbuf.h>
  85 #include <sys/priv.h>
  86 #include <sys/proc.h>
  87 #include <sys/protosw.h>
  88 #include <sys/sdt.h>
  89 #include <sys/signalvar.h>
  90 #include <sys/socket.h>
  91 #include <sys/socketvar.h>
  92 #include <sys/sx.h>
  93 #include <sys/sysctl.h>
  94 #include <sys/syslog.h>
  95 #include <sys/systm.h>
  96
  97 #include <net/if.h>
  98 #include <net/if_var.h>
  99 #include <net/if_types.h>
 100 #include <net/route.h>
 101 #include <net/rss_config.h>
 102
 103 #include <netinet/in.h>
 104 #include <netinet/in_kdtrace.h>
 105 #include <netinet/in_pcb.h>
 106 #include <netinet/in_systm.h>
 107 #include <netinet/in_var.h>
 108 #include <netinet/ip.h>
 109 #include <netinet/ip6.h>
 110 #include <netinet/icmp6.h>
 111 #include <netinet/ip_var.h>
 112 #include <netinet/udp.h>
 113 #include <netinet/udp_var.h>
 114 #include <netinet/udplite.h>
 115
 116 #include <netinet6/ip6protosw.h>
 117 #include <netinet6/ip6_var.h>
 118 #include <netinet6/in6_pcb.h>
 119 #include <netinet6/in6_rss.h>
 120 #include <netinet6/udp6_var.h>
 121 #include <netinet6/scope6_var.h>
 122
 123 #include <netipsec/ipsec_support.h>
 124
 125 #include <security/mac/mac_framework.h>
 126
 127 /*
 128  * UDP protocol implementation.
 129  * Per RFC 768, August, 1980.
 130  */
 131
 132 extern struct protosw   inetsw[];
 133 static void             udp6_detach(struct socket *so);
 134
 135 static int
 136 udp6_append(struct inpcb *inp, struct mbuf *n, int off,
 137     struct sockaddr_in6 *fromsa)
 138 {
 139         struct socket *so;
 140         struct mbuf *opts = NULL, *tmp_opts;
 141         struct udpcb *up;
 142
 143         INP_LOCK_ASSERT(inp);
 144
 145         /*
 146          * Engage the tunneling protocol.
 147          */
 148         up = intoudpcb(inp);
 149         if (up->u_tun_func != NULL) {
 150                 in_pcbref(inp);
 151                 INP_RUNLOCK(inp);
 152                 (*up->u_tun_func)(n, off, inp, (struct sockaddr *)&fromsa[0],
 153                     up->u_tun_ctx);
 154                 INP_RLOCK(inp);
 155                 return (in_pcbrele_rlocked(inp));
 156         }
 157 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 158         /* Check AH/ESP integrity. */
 159         if (IPSEC_ENABLED(ipv6)) {
 160                 if (IPSEC_CHECK_POLICY(ipv6, n, inp) != 0) {
 161                         m_freem(n);
 162                         return (0);
 163                 }
 164         }
 165 #endif /* IPSEC */
 166 #ifdef MAC
 167         if (mac_inpcb_check_deliver(inp, n) != 0) {
 168                 m_freem(n);
 169                 return (0);
 170         }
 171 #endif
 172         opts = NULL;
 173         if (inp->inp_flags & INP_CONTROLOPTS ||
 174             inp->inp_socket->so_options & SO_TIMESTAMP)
 175                 ip6_savecontrol(inp, n, &opts);
 176         if ((inp->inp_vflag & INP_IPV6) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
 177                 tmp_opts = sbcreatecontrol((caddr_t)&fromsa[1],
 178                         sizeof(struct sockaddr_in6), IPV6_ORIGDSTADDR, IPPROTO_IPV6);
 179                 if (tmp_opts) {
 180                         if (opts) {
 181                                 tmp_opts->m_next = opts;
 182                                 opts = tmp_opts;
 183                         } else
 184                                 opts = tmp_opts;
 185                 }
 186
 187         }
 188         m_adj(n, off + sizeof(struct udphdr));
 189
 190         so = inp->inp_socket;
 191         SOCKBUF_LOCK(&so->so_rcv);
 192         if (sbappendaddr_locked(&so->so_rcv, (struct sockaddr *)&fromsa[0], n,
 193             opts) == 0) {
 194                 SOCKBUF_UNLOCK(&so->so_rcv);
 195                 m_freem(n);
 196                 if (opts)
 197                         m_freem(opts);
 198                 UDPSTAT_INC(udps_fullsock);
 199         } else
 200                 sorwakeup_locked(so);
 201         return (0);
 202 }
 203
 204 int
 205 udp6_input(struct mbuf **mp, int *offp, int proto)
 206 {
 207         struct mbuf *m = *mp;
 208         struct ifnet *ifp;
 209         struct ip6_hdr *ip6;
 210         struct udphdr *uh;
 211         struct inpcb *inp;
 212         struct inpcbinfo *pcbinfo;
 213         struct udpcb *up;
 214         int off = *offp;
 215         int cscov_partial;
 216         int plen, ulen;
 217         struct epoch_tracker et;
 218         struct sockaddr_in6 fromsa[2];
 219         struct m_tag *fwd_tag;
 220         uint16_t uh_sum;
 221         uint8_t nxt;
 222
 223         ifp = m->m_pkthdr.rcvif;
 224
 225 #ifndef PULLDOWN_TEST
 226         IP6_EXTHDR_CHECK(m, off, sizeof(struct udphdr), IPPROTO_DONE);
 227         ip6 = mtod(m, struct ip6_hdr *);
 228         uh = (struct udphdr *)((caddr_t)ip6 + off);
 229 #else
 230         IP6_EXTHDR_GET(uh, struct udphdr *, m, off, sizeof(*uh));
 231         if (!uh)
 232                 return (IPPROTO_DONE);
 233         ip6 = mtod(m, struct ip6_hdr *);
 234 #endif
 235
 236         UDPSTAT_INC(udps_ipackets);
 237
 238         /*
 239          * Destination port of 0 is illegal, based on RFC768.
 240          */
 241         if (uh->uh_dport == 0)
 242                 goto badunlocked;
 243
 244         plen = ntohs(ip6->ip6_plen) - off + sizeof(*ip6);
 245         ulen = ntohs((u_short)uh->uh_ulen);
 246
 247         nxt = proto;
 248         cscov_partial = (nxt == IPPROTO_UDPLITE) ? 1 : 0;
 249         if (nxt == IPPROTO_UDPLITE) {
 250                 /* Zero means checksum over the complete packet. */
 251                 if (ulen == 0)
 252                         ulen = plen;
 253                 if (ulen == plen)
 254                         cscov_partial = 0;
 255                 if ((ulen < sizeof(struct udphdr)) || (ulen > plen)) {
 256                         /* XXX: What is the right UDPLite MIB counter? */
 257                         goto badunlocked;
 258                 }
 259                 if (uh->uh_sum == 0) {
 260                         /* XXX: What is the right UDPLite MIB counter? */
 261                         goto badunlocked;
 262                 }
 263         } else {
 264                 if ((ulen < sizeof(struct udphdr)) || (plen != ulen)) {
 265                         UDPSTAT_INC(udps_badlen);
 266                         goto badunlocked;
 267                 }
 268                 if (uh->uh_sum == 0) {
 269                         UDPSTAT_INC(udps_nosum);
 270                         goto badunlocked;
 271                 }
 272         }
 273
 274         if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID_IPV6) &&
 275             !cscov_partial) {
 276                 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
 277                         uh_sum = m->m_pkthdr.csum_data;
 278                 else
 279                         uh_sum = in6_cksum_pseudo(ip6, ulen, nxt,
 280                             m->m_pkthdr.csum_data);
 281                 uh_sum ^= 0xffff;
 282         } else
 283                 uh_sum = in6_cksum_partial(m, nxt, off, plen, ulen);
 284
 285         if (uh_sum != 0) {
 286                 UDPSTAT_INC(udps_badsum);
 287                 goto badunlocked;
 288         }
 289
 290         /*
 291          * Construct sockaddr format source address.
 292          */
 293         init_sin6(&fromsa[0], m, 0);
 294         fromsa[0].sin6_port = uh->uh_sport;
 295         init_sin6(&fromsa[1], m, 1);
 296         fromsa[1].sin6_port = uh->uh_dport;
 297
 298         pcbinfo = udp_get_inpcbinfo(nxt);
 299         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 300                 struct inpcb *last;
 301                 struct inpcbhead *pcblist;
 302                 struct ip6_moptions *imo;
 303
 304                 INP_INFO_RLOCK_ET(pcbinfo, et);
 305                 /*
 306                  * In the event that laddr should be set to the link-local
 307                  * address (this happens in RIPng), the multicast address
 308                  * specified in the received packet will not match laddr.  To
 309                  * handle this situation, matching is relaxed if the
 310                  * receiving interface is the same as one specified in the
 311                  * socket and if the destination multicast address matches
 312                  * one of the multicast groups specified in the socket.
 313                  */
 314
 315                 /*
 316                  * KAME note: traditionally we dropped udpiphdr from mbuf
 317                  * here.  We need udphdr for IPsec processing so we do that
 318                  * later.
 319                  */
 320                 pcblist = udp_get_pcblist(nxt);
 321                 last = NULL;
 322                 CK_LIST_FOREACH(inp, pcblist, inp_list) {
 323                         if ((inp->inp_vflag & INP_IPV6) == 0)
 324                                 continue;
 325                         if (inp->inp_lport != uh->uh_dport)
 326                                 continue;
 327                         if (inp->inp_fport != 0 &&
 328                             inp->inp_fport != uh->uh_sport)
 329                                 continue;
 330                         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
 331                                 if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr,
 332                                                         &ip6->ip6_dst))
 333                                         continue;
 334                         }
 335                         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 336                                 if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr,
 337                                                         &ip6->ip6_src) ||
 338                                     inp->inp_fport != uh->uh_sport)
 339                                         continue;
 340                         }
 341
 342                         /*
 343                          * XXXRW: Because we weren't holding either the inpcb
 344                          * or the hash lock when we checked for a match
 345                          * before, we should probably recheck now that the
 346                          * inpcb lock is (supposed to be) held.
 347                          */
 348
 349                         /*
 350                          * Handle socket delivery policy for any-source
 351                          * and source-specific multicast. [RFC3678]
 352                          */
 353                         imo = inp->in6p_moptions;
 354                         if (imo && IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 355                                 struct sockaddr_in6      mcaddr;
 356                                 int                      blocked;
 357
 358                                 INP_RLOCK(inp);
 359                                 if (__predict_false(inp->inp_flags2 & INP_FREED)) {
 360                                         INP_RUNLOCK(inp);
 361                                         continue;
 362                                 }
 363
 364                                 bzero(&mcaddr, sizeof(struct sockaddr_in6));
 365                                 mcaddr.sin6_len = sizeof(struct sockaddr_in6);
 366                                 mcaddr.sin6_family = AF_INET6;
 367                                 mcaddr.sin6_addr = ip6->ip6_dst;
 368
 369                                 blocked = im6o_mc_filter(imo, ifp,
 370                                         (struct sockaddr *)&mcaddr,
 371                                         (struct sockaddr *)&fromsa[0]);
 372                                 if (blocked != MCAST_PASS) {
 373                                         if (blocked == MCAST_NOTGMEMBER)
 374                                                 IP6STAT_INC(ip6s_notmember);
 375                                         if (blocked == MCAST_NOTSMEMBER ||
 376                                             blocked == MCAST_MUTED)
 377                                                 UDPSTAT_INC(udps_filtermcast);
 378                                         INP_RUNLOCK(inp); /* XXX */
 379                                         continue;
 380                                 }
 381
 382                                 INP_RUNLOCK(inp);
 383                         }
 384                         if (last != NULL) {
 385                                 struct mbuf *n;
 386
 387                                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) !=
 388                                     NULL) {
 389                                         INP_RLOCK(last);
 390                                         if (__predict_true(last->inp_flags2 & INP_FREED) == 0) {
 391                                                 UDP_PROBE(receive, NULL, last, ip6,
 392                                                 last, uh);
 393                                                 if (udp6_append(last, n, off, fromsa))
 394                                                         goto inp_lost;
 395                                         }
 396                                         INP_RUNLOCK(last);
 397                                 }
 398                         }
 399                         last = inp;
 400                         /*
 401                          * Don't look for additional matches if this one does
 402                          * not have either the SO_REUSEPORT or SO_REUSEADDR
 403                          * socket options set.  This heuristic avoids
 404                          * searching through all pcbs in the common case of a
 405                          * non-shared port.  It assumes that an application
 406                          * will never clear these options after setting them.
 407                          */
 408                         if ((last->inp_socket->so_options &
 409                              (SO_REUSEPORT|SO_REUSEPORT_LB|SO_REUSEADDR)) == 0)
 410                                 break;
 411                 }
 412
 413                 if (last == NULL) {
 414                         /*
 415                          * No matching pcb found; discard datagram.  (No need
 416                          * to send an ICMP Port Unreachable for a broadcast
 417                          * or multicast datgram.)
 418                          */
 419                         UDPSTAT_INC(udps_noport);
 420                         UDPSTAT_INC(udps_noportmcast);
 421                         goto badheadlocked;
 422                 }
 423                 INP_RLOCK(last);
 424                 if (__predict_true(last->inp_flags2 & INP_FREED) == 0) {
 425                         UDP_PROBE(receive, NULL, last, ip6, last, uh);
 426                         if (udp6_append(last, m, off, fromsa) == 0)
 427                                 INP_RUNLOCK(last);
 428                 } else
 429                         INP_RUNLOCK(last);
 430                 INP_INFO_RUNLOCK_ET(pcbinfo, et);
 431         inp_lost:
 432                 return (IPPROTO_DONE);
 433         }
 434         /*
 435          * Locate pcb for datagram.
 436          */
 437
 438         /*
 439          * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
 440          */
 441         if ((m->m_flags & M_IP6_NEXTHOP) &&
 442             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 443                 struct sockaddr_in6 *next_hop6;
 444
 445                 next_hop6 = (struct sockaddr_in6 *)(fwd_tag + 1);
 446
 447                 /*
 448                  * Transparently forwarded. Pretend to be the destination.
 449                  * Already got one like this?
 450                  */
 451                 inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_src,
 452                     uh->uh_sport, &ip6->ip6_dst, uh->uh_dport,
 453                     INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif, m);
 454                 if (!inp) {
 455                         /*
 456                          * It's new.  Try to find the ambushing socket.
 457                          * Because we've rewritten the destination address,
 458                          * any hardware-generated hash is ignored.
 459                          */
 460                         inp = in6_pcblookup(pcbinfo, &ip6->ip6_src,
 461                             uh->uh_sport, &next_hop6->sin6_addr,
 462                             next_hop6->sin6_port ? htons(next_hop6->sin6_port) :
 463                             uh->uh_dport, INPLOOKUP_WILDCARD |
 464                             INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif);
 465                 }
 466                 /* Remove the tag from the packet. We don't need it anymore. */
 467                 m_tag_delete(m, fwd_tag);
 468                 m->m_flags &= ~M_IP6_NEXTHOP;
 469         } else
 470                 inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_src,
 471                     uh->uh_sport, &ip6->ip6_dst, uh->uh_dport,
 472                     INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB,
 473                     m->m_pkthdr.rcvif, m);
 474         if (inp == NULL) {
 475                 if (udp_log_in_vain) {
 476                         char ip6bufs[INET6_ADDRSTRLEN];
 477                         char ip6bufd[INET6_ADDRSTRLEN];
 478
 479                         log(LOG_INFO,
 480                             "Connection attempt to UDP [%s]:%d from [%s]:%d\n",
 481                             ip6_sprintf(ip6bufd, &ip6->ip6_dst),
 482                             ntohs(uh->uh_dport),
 483                             ip6_sprintf(ip6bufs, &ip6->ip6_src),
 484                             ntohs(uh->uh_sport));
 485                 }
 486                 UDP_PROBE(receive, NULL, NULL, ip6, NULL, uh);
 487                 UDPSTAT_INC(udps_noport);
 488                 if (m->m_flags & M_MCAST) {
 489                         printf("UDP6: M_MCAST is set in a unicast packet.\n");
 490                         UDPSTAT_INC(udps_noportmcast);
 491                         goto badunlocked;
 492                 }
 493                 if (V_udp_blackhole)
 494                         goto badunlocked;
 495                 icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
 496                 return (IPPROTO_DONE);
 497         }
 498         INP_RLOCK_ASSERT(inp);
 499         up = intoudpcb(inp);
 500         if (cscov_partial) {
 501                 if (up->u_rxcslen == 0 || up->u_rxcslen > ulen) {
 502                         INP_RUNLOCK(inp);
 503                         m_freem(m);
 504                         return (IPPROTO_DONE);
 505                 }
 506         }
 507         UDP_PROBE(receive, NULL, inp, ip6, inp, uh);
 508         if (udp6_append(inp, m, off, fromsa) == 0)
 509                 INP_RUNLOCK(inp);
 510         return (IPPROTO_DONE);
 511
 512 badheadlocked:
 513         INP_INFO_RUNLOCK_ET(pcbinfo, et);
 514 badunlocked:
 515         if (m)
 516                 m_freem(m);
 517         return (IPPROTO_DONE);
 518 }
 519
 520 static void
 521 udp6_common_ctlinput(int cmd, struct sockaddr *sa, void *d,
 522     struct inpcbinfo *pcbinfo)
 523 {
 524         struct udphdr uh;
 525         struct ip6_hdr *ip6;
 526         struct mbuf *m;
 527         int off = 0;
 528         struct ip6ctlparam *ip6cp = NULL;
 529         const struct sockaddr_in6 *sa6_src = NULL;
 530         void *cmdarg;
 531         struct inpcb *(*notify)(struct inpcb *, int) = udp_notify;
 532         struct udp_portonly {
 533                 u_int16_t uh_sport;
 534                 u_int16_t uh_dport;
 535         } *uhp;
 536
 537         if (sa->sa_family != AF_INET6 ||
 538             sa->sa_len != sizeof(struct sockaddr_in6))
 539                 return;
 540
 541         if ((unsigned)cmd >= PRC_NCMDS)
 542                 return;
 543         if (PRC_IS_REDIRECT(cmd))
 544                 notify = in6_rtchange, d = NULL;
 545         else if (cmd == PRC_HOSTDEAD)
 546                 d = NULL;
 547         else if (inet6ctlerrmap[cmd] == 0)
 548                 return;
 549
 550         /* if the parameter is from icmp6, decode it. */
 551         if (d != NULL) {
 552                 ip6cp = (struct ip6ctlparam *)d;
 553                 m = ip6cp->ip6c_m;
 554                 ip6 = ip6cp->ip6c_ip6;
 555                 off = ip6cp->ip6c_off;
 556                 cmdarg = ip6cp->ip6c_cmdarg;
 557                 sa6_src = ip6cp->ip6c_src;
 558         } else {
 559                 m = NULL;
 560                 ip6 = NULL;
 561                 cmdarg = NULL;
 562                 sa6_src = &sa6_any;
 563         }
 564
 565         if (ip6) {
 566                 /*
 567                  * XXX: We assume that when IPV6 is non NULL,
 568                  * M and OFF are valid.
 569                  */
 570
 571                 /* Check if we can safely examine src and dst ports. */
 572                 if (m->m_pkthdr.len < off + sizeof(*uhp))
 573                         return;
 574
 575                 bzero(&uh, sizeof(uh));
 576                 m_copydata(m, off, sizeof(*uhp), (caddr_t)&uh);
 577
 578                 if (!PRC_IS_REDIRECT(cmd)) {
 579                         /* Check to see if its tunneled */
 580                         struct inpcb *inp;
 581                         inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_dst,
 582                             uh.uh_dport, &ip6->ip6_src, uh.uh_sport,
 583                             INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB,
 584                             m->m_pkthdr.rcvif, m);
 585                         if (inp != NULL) {
 586                                 struct udpcb *up;
 587
 588                                 up = intoudpcb(inp);
 589                                 if (up->u_icmp_func) {
 590                                         /* Yes it is. */
 591                                         INP_RUNLOCK(inp);
 592                                         (*up->u_icmp_func)(cmd, (struct sockaddr *)ip6cp->ip6c_src,
 593                                               d, up->u_tun_ctx);
 594                                         return;
 595                                 } else {
 596                                         /* Can't find it. */
 597                                         INP_RUNLOCK(inp);
 598                                 }
 599                         }
 600                 }
 601                 (void)in6_pcbnotify(pcbinfo, sa, uh.uh_dport,
 602                     (struct sockaddr *)ip6cp->ip6c_src, uh.uh_sport, cmd,
 603                     cmdarg, notify);
 604         } else
 605                 (void)in6_pcbnotify(pcbinfo, sa, 0,
 606                     (const struct sockaddr *)sa6_src, 0, cmd, cmdarg, notify);
 607 }
 608
 609 void
 610 udp6_ctlinput(int cmd, struct sockaddr *sa, void *d)
 611 {
 612
 613         return (udp6_common_ctlinput(cmd, sa, d, &V_udbinfo));
 614 }
 615
 616 void
 617 udplite6_ctlinput(int cmd, struct sockaddr *sa, void *d)
 618 {
 619
 620         return (udp6_common_ctlinput(cmd, sa, d, &V_ulitecbinfo));
 621 }
 622
 623 static int
 624 udp6_getcred(SYSCTL_HANDLER_ARGS)
 625 {
 626         struct xucred xuc;
 627         struct sockaddr_in6 addrs[2];
 628         struct inpcb *inp;
 629         int error;
 630
 631         error = priv_check(req->td, PRIV_NETINET_GETCRED);
 632         if (error)
 633                 return (error);
 634
 635         if (req->newlen != sizeof(addrs))
 636                 return (EINVAL);
 637         if (req->oldlen != sizeof(struct xucred))
 638                 return (EINVAL);
 639         error = SYSCTL_IN(req, addrs, sizeof(addrs));
 640         if (error)
 641                 return (error);
 642         if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 ||
 643             (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) {
 644                 return (error);
 645         }
 646         inp = in6_pcblookup(&V_udbinfo, &addrs[1].sin6_addr,
 647             addrs[1].sin6_port, &addrs[0].sin6_addr, addrs[0].sin6_port,
 648             INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 649         if (inp != NULL) {
 650                 INP_RLOCK_ASSERT(inp);
 651                 if (inp->inp_socket == NULL)
 652                         error = ENOENT;
 653                 if (error == 0)
 654                         error = cr_canseesocket(req->td->td_ucred,
 655                             inp->inp_socket);
 656                 if (error == 0)
 657                         cru2x(inp->inp_cred, &xuc);
 658                 INP_RUNLOCK(inp);
 659         } else
 660                 error = ENOENT;
 661         if (error == 0)
 662                 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
 663         return (error);
 664 }
 665
 666 SYSCTL_PROC(_net_inet6_udp6, OID_AUTO, getcred, CTLTYPE_OPAQUE|CTLFLAG_RW, 0,
 667     0, udp6_getcred, "S,xucred", "Get the xucred of a UDP6 connection");
 668
 669 static int
 670 udp6_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr6,
 671     struct mbuf *control, struct thread *td)
 672 {
 673         u_int32_t ulen = m->m_pkthdr.len;
 674         u_int32_t plen = sizeof(struct udphdr) + ulen;
 675         struct ip6_hdr *ip6;
 676         struct udphdr *udp6;
 677         struct in6_addr *laddr, *faddr, in6a;
 678         struct sockaddr_in6 *sin6 = NULL;
 679         int cscov_partial = 0;
 680         int scope_ambiguous = 0;
 681         u_short fport;
 682         int error = 0;
 683         uint8_t nxt;
 684         uint16_t cscov = 0;
 685         struct ip6_pktopts *optp, opt;
 686         int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
 687         int flags;
 688         struct sockaddr_in6 tmp;
 689
 690         INP_WLOCK_ASSERT(inp);
 691         INP_HASH_WLOCK_ASSERT(inp->inp_pcbinfo);
 692
 693         if (addr6) {
 694                 /* addr6 has been validated in udp6_send(). */
 695                 sin6 = (struct sockaddr_in6 *)addr6;
 696
 697                 /* protect *sin6 from overwrites */
 698                 tmp = *sin6;
 699                 sin6 = &tmp;
 700
 701                 /*
 702                  * Application should provide a proper zone ID or the use of
 703                  * default zone IDs should be enabled.  Unfortunately, some
 704                  * applications do not behave as it should, so we need a
 705                  * workaround.  Even if an appropriate ID is not determined,
 706                  * we'll see if we can determine the outgoing interface.  If we
 707                  * can, determine the zone ID based on the interface below.
 708                  */
 709                 if (sin6->sin6_scope_id == 0 && !V_ip6_use_defzone)
 710                         scope_ambiguous = 1;
 711                 if ((error = sa6_embedscope(sin6, V_ip6_use_defzone)) != 0)
 712                         return (error);
 713         }
 714
 715         nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
 716             IPPROTO_UDP : IPPROTO_UDPLITE;
 717         if (control) {
 718                 if ((error = ip6_setpktopts(control, &opt,
 719                     inp->in6p_outputopts, td->td_ucred, nxt)) != 0)
 720                         goto release;
 721                 optp = &opt;
 722         } else
 723                 optp = inp->in6p_outputopts;
 724
 725         if (sin6) {
 726                 faddr = &sin6->sin6_addr;
 727
 728                 /*
 729                  * Since we saw no essential reason for calling in_pcbconnect,
 730                  * we get rid of such kind of logic, and call in6_selectsrc
 731                  * and in6_pcbsetport in order to fill in the local address
 732                  * and the local port.
 733                  */
 734                 if (sin6->sin6_port == 0) {
 735                         error = EADDRNOTAVAIL;
 736                         goto release;
 737                 }
 738
 739                 if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 740                         /* how about ::ffff:0.0.0.0 case? */
 741                         error = EISCONN;
 742                         goto release;
 743                 }
 744
 745                 fport = sin6->sin6_port; /* allow 0 port */
 746
 747                 if (IN6_IS_ADDR_V4MAPPED(faddr)) {
 748                         if ((inp->inp_flags & IN6P_IPV6_V6ONLY)) {
 749                                 /*
 750                                  * I believe we should explicitly discard the
 751                                  * packet when mapped addresses are disabled,
 752                                  * rather than send the packet as an IPv6 one.
 753                                  * If we chose the latter approach, the packet
 754                                  * might be sent out on the wire based on the
 755                                  * default route, the situation which we'd
 756                                  * probably want to avoid.
 757                                  * (20010421 jinmei@kame.net)
 758                                  */
 759                                 error = EINVAL;
 760                                 goto release;
 761                         }
 762                         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
 763                             !IN6_IS_ADDR_V4MAPPED(&inp->in6p_laddr)) {
 764                                 /*
 765                                  * when remote addr is an IPv4-mapped address,
 766                                  * local addr should not be an IPv6 address,
 767                                  * since you cannot determine how to map IPv6
 768                                  * source address to IPv4.
 769                                  */
 770                                 error = EINVAL;
 771                                 goto release;
 772                         }
 773
 774                         af = AF_INET;
 775                 }
 776
 777                 if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
 778                         error = in6_selectsrc_socket(sin6, optp, inp,
 779                             td->td_ucred, scope_ambiguous, &in6a, NULL);
 780                         if (error)
 781                                 goto release;
 782                         laddr = &in6a;
 783                 } else
 784                         laddr = &inp->in6p_laddr;       /* XXX */
 785                 if (laddr == NULL) {
 786                         if (error == 0)
 787                                 error = EADDRNOTAVAIL;
 788                         goto release;
 789                 }
 790                 if (inp->inp_lport == 0 &&
 791                     (error = in6_pcbsetport(laddr, inp, td->td_ucred)) != 0) {
 792                         /* Undo an address bind that may have occurred. */
 793                         inp->in6p_laddr = in6addr_any;
 794                         goto release;
 795                 }
 796         } else {
 797                 if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 798                         error = ENOTCONN;
 799                         goto release;
 800                 }
 801                 if (IN6_IS_ADDR_V4MAPPED(&inp->in6p_faddr)) {
 802                         if ((inp->inp_flags & IN6P_IPV6_V6ONLY)) {
 803                                 /*
 804                                  * XXX: this case would happen when the
 805                                  * application sets the V6ONLY flag after
 806                                  * connecting the foreign address.
 807                                  * Such applications should be fixed,
 808                                  * so we bark here.
 809                                  */
 810                                 log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
 811                                     "option was set for a connected socket\n");
 812                                 error = EINVAL;
 813                                 goto release;
 814                         } else
 815                                 af = AF_INET;
 816                 }
 817                 laddr = &inp->in6p_laddr;
 818                 faddr = &inp->in6p_faddr;
 819                 fport = inp->inp_fport;
 820         }
 821
 822         if (af == AF_INET)
 823                 hlen = sizeof(struct ip);
 824
 825         /*
 826          * Calculate data length and get a mbuf
 827          * for UDP and IP6 headers.
 828          */
 829         M_PREPEND(m, hlen + sizeof(struct udphdr), M_NOWAIT);
 830         if (m == NULL) {
 831                 error = ENOBUFS;
 832                 goto release;
 833         }
 834
 835         /*
 836          * Stuff checksum and output datagram.
 837          */
 838         udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
 839         udp6->uh_sport = inp->inp_lport; /* lport is always set in the PCB */
 840         udp6->uh_dport = fport;
 841         if (nxt == IPPROTO_UDPLITE) {
 842                 struct udpcb *up;
 843
 844                 up = intoudpcb(inp);
 845                 cscov = up->u_txcslen;
 846                 if (cscov >= plen)
 847                         cscov = 0;
 848                 udp6->uh_ulen = htons(cscov);
 849                 /*
 850                  * For UDP-Lite, checksum coverage length of zero means
 851                  * the entire UDPLite packet is covered by the checksum.
 852                  */
 853                 cscov_partial = (cscov == 0) ? 0 : 1;
 854         } else if (plen <= 0xffff)
 855                 udp6->uh_ulen = htons((u_short)plen);
 856         else
 857                 udp6->uh_ulen = 0;
 858         udp6->uh_sum = 0;
 859
 860         switch (af) {
 861         case AF_INET6:
 862                 ip6 = mtod(m, struct ip6_hdr *);
 863                 ip6->ip6_flow   = inp->inp_flow & IPV6_FLOWINFO_MASK;
 864                 ip6->ip6_vfc    &= ~IPV6_VERSION_MASK;
 865                 ip6->ip6_vfc    |= IPV6_VERSION;
 866                 ip6->ip6_plen   = htons((u_short)plen);
 867                 ip6->ip6_nxt    = nxt;
 868                 ip6->ip6_hlim   = in6_selecthlim(inp, NULL);
 869                 ip6->ip6_src    = *laddr;
 870                 ip6->ip6_dst    = *faddr;
 871
 872                 if (cscov_partial) {
 873                         if ((udp6->uh_sum = in6_cksum_partial(m, nxt,
 874                             sizeof(struct ip6_hdr), plen, cscov)) == 0)
 875                                 udp6->uh_sum = 0xffff;
 876                 } else {
 877                         udp6->uh_sum = in6_cksum_pseudo(ip6, plen, nxt, 0);
 878                         m->m_pkthdr.csum_flags = CSUM_UDP_IPV6;
 879                         m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
 880                 }
 881
 882 #ifdef  RSS
 883                 {
 884                         uint32_t hash_val, hash_type;
 885                         uint8_t pr;
 886
 887                         pr = inp->inp_socket->so_proto->pr_protocol;
 888                         /*
 889                          * Calculate an appropriate RSS hash for UDP and
 890                          * UDP Lite.
 891                          *
 892                          * The called function will take care of figuring out
 893                          * whether a 2-tuple or 4-tuple hash is required based
 894                          * on the currently configured scheme.
 895                          *
 896                          * Later later on connected socket values should be
 897                          * cached in the inpcb and reused, rather than constantly
 898                          * re-calculating it.
 899                          *
 900                          * UDP Lite is a different protocol number and will
 901                          * likely end up being hashed as a 2-tuple until
 902                          * RSS / NICs grow UDP Lite protocol awareness.
 903                          */
 904                         if (rss_proto_software_hash_v6(faddr, laddr, fport,
 905                             inp->inp_lport, pr, &hash_val, &hash_type) == 0) {
 906                                 m->m_pkthdr.flowid = hash_val;
 907                                 M_HASHTYPE_SET(m, hash_type);
 908                         }
 909                 }
 910 #endif
 911                 flags = 0;
 912 #ifdef  RSS
 913                 /*
 914                  * Don't override with the inp cached flowid.
 915                  *
 916                  * Until the whole UDP path is vetted, it may actually
 917                  * be incorrect.
 918                  */
 919                 flags |= IP_NODEFAULTFLOWID;
 920 #endif
 921
 922                 UDP_PROBE(send, NULL, inp, ip6, inp, udp6);
 923                 UDPSTAT_INC(udps_opackets);
 924                 error = ip6_output(m, optp, &inp->inp_route6, flags,
 925                     inp->in6p_moptions, NULL, inp);
 926                 break;
 927         case AF_INET:
 928                 error = EAFNOSUPPORT;
 929                 goto release;
 930         }
 931         goto releaseopt;
 932
 933 release:
 934         m_freem(m);
 935
 936 releaseopt:
 937         if (control) {
 938                 ip6_clearpktopts(&opt, -1);
 939                 m_freem(control);
 940         }
 941         return (error);
 942 }
 943
 944 static void
 945 udp6_abort(struct socket *so)
 946 {
 947         struct inpcb *inp;
 948         struct inpcbinfo *pcbinfo;
 949
 950         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
 951         inp = sotoinpcb(so);
 952         KASSERT(inp != NULL, ("udp6_abort: inp == NULL"));
 953
 954         INP_WLOCK(inp);
 955 #ifdef INET
 956         if (inp->inp_vflag & INP_IPV4) {
 957                 struct pr_usrreqs *pru;
 958                 uint8_t nxt;
 959
 960                 nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
 961                     IPPROTO_UDP : IPPROTO_UDPLITE;
 962                 INP_WUNLOCK(inp);
 963                 pru = inetsw[ip_protox[nxt]].pr_usrreqs;
 964                 (*pru->pru_abort)(so);
 965                 return;
 966         }
 967 #endif
 968
 969         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 970                 INP_HASH_WLOCK(pcbinfo);
 971                 in6_pcbdisconnect(inp);
 972                 inp->in6p_laddr = in6addr_any;
 973                 INP_HASH_WUNLOCK(pcbinfo);
 974                 soisdisconnected(so);
 975         }
 976         INP_WUNLOCK(inp);
 977 }
 978
 979 static int
 980 udp6_attach(struct socket *so, int proto, struct thread *td)
 981 {
 982         struct inpcb *inp;
 983         struct inpcbinfo *pcbinfo;
 984         int error;
 985
 986         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
 987         inp = sotoinpcb(so);
 988         KASSERT(inp == NULL, ("udp6_attach: inp != NULL"));
 989
 990         if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
 991                 error = soreserve(so, udp_sendspace, udp_recvspace);
 992                 if (error)
 993                         return (error);
 994         }
 995         INP_INFO_WLOCK(pcbinfo);
 996         error = in_pcballoc(so, pcbinfo);
 997         if (error) {
 998                 INP_INFO_WUNLOCK(pcbinfo);
 999                 return (error);
1000         }
1001         inp = (struct inpcb *)so->so_pcb;
1002         inp->inp_vflag |= INP_IPV6;
1003         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
1004                 inp->inp_vflag |= INP_IPV4;
1005         inp->in6p_hops = -1;    /* use kernel default */
1006         inp->in6p_cksum = -1;   /* just to be sure */
1007         /*
1008          * XXX: ugly!!
1009          * IPv4 TTL initialization is necessary for an IPv6 socket as well,
1010          * because the socket may be bound to an IPv6 wildcard address,
1011          * which may match an IPv4-mapped IPv6 address.
1012          */
1013         inp->inp_ip_ttl = V_ip_defttl;
1014
1015         error = udp_newudpcb(inp);
1016         if (error) {
1017                 in_pcbdetach(inp);
1018                 in_pcbfree(inp);
1019                 INP_INFO_WUNLOCK(pcbinfo);
1020                 return (error);
1021         }
1022         INP_WUNLOCK(inp);
1023         INP_INFO_WUNLOCK(pcbinfo);
1024         return (0);
1025 }
1026
1027 static int
1028 udp6_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1029 {
1030         struct inpcb *inp;
1031         struct inpcbinfo *pcbinfo;
1032         int error;
1033
1034         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1035         inp = sotoinpcb(so);
1036         KASSERT(inp != NULL, ("udp6_bind: inp == NULL"));
1037
1038         INP_WLOCK(inp);
1039         INP_HASH_WLOCK(pcbinfo);
1040         inp->inp_vflag &= ~INP_IPV4;
1041         inp->inp_vflag |= INP_IPV6;
1042         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
1043                 struct sockaddr_in6 *sin6_p;
1044
1045                 sin6_p = (struct sockaddr_in6 *)nam;
1046
1047                 if (IN6_IS_ADDR_UNSPECIFIED(&sin6_p->sin6_addr))
1048                         inp->inp_vflag |= INP_IPV4;
1049 #ifdef INET
1050                 else if (IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {
1051                         struct sockaddr_in sin;
1052
1053                         in6_sin6_2_sin(&sin, sin6_p);
1054                         inp->inp_vflag |= INP_IPV4;
1055                         inp->inp_vflag &= ~INP_IPV6;
1056                         error = in_pcbbind(inp, (struct sockaddr *)&sin,
1057                             td->td_ucred);
1058                         goto out;
1059                 }
1060 #endif
1061         }
1062
1063         error = in6_pcbbind(inp, nam, td->td_ucred);
1064 #ifdef INET
1065 out:
1066 #endif
1067         INP_HASH_WUNLOCK(pcbinfo);
1068         INP_WUNLOCK(inp);
1069         return (error);
1070 }
1071
1072 static void
1073 udp6_close(struct socket *so)
1074 {
1075         struct inpcb *inp;
1076         struct inpcbinfo *pcbinfo;
1077
1078         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1079         inp = sotoinpcb(so);
1080         KASSERT(inp != NULL, ("udp6_close: inp == NULL"));
1081
1082         INP_WLOCK(inp);
1083 #ifdef INET
1084         if (inp->inp_vflag & INP_IPV4) {
1085                 struct pr_usrreqs *pru;
1086                 uint8_t nxt;
1087
1088                 nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
1089                     IPPROTO_UDP : IPPROTO_UDPLITE;
1090                 INP_WUNLOCK(inp);
1091                 pru = inetsw[ip_protox[nxt]].pr_usrreqs;
1092                 (*pru->pru_disconnect)(so);
1093                 return;
1094         }
1095 #endif
1096         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1097                 INP_HASH_WLOCK(pcbinfo);
1098                 in6_pcbdisconnect(inp);
1099                 inp->in6p_laddr = in6addr_any;
1100                 INP_HASH_WUNLOCK(pcbinfo);
1101                 soisdisconnected(so);
1102         }
1103         INP_WUNLOCK(inp);
1104 }
1105
1106 static int
1107 udp6_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1108 {
1109         struct inpcb *inp;
1110         struct inpcbinfo *pcbinfo;
1111         struct sockaddr_in6 *sin6;
1112         int error;
1113
1114         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1115         inp = sotoinpcb(so);
1116         sin6 = (struct sockaddr_in6 *)nam;
1117         KASSERT(inp != NULL, ("udp6_connect: inp == NULL"));
1118
1119         /*
1120          * XXXRW: Need to clarify locking of v4/v6 flags.
1121          */
1122         INP_WLOCK(inp);
1123 #ifdef INET
1124         if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
1125                 struct sockaddr_in sin;
1126
1127                 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
1128                         error = EINVAL;
1129                         goto out;
1130                 }
1131                 if ((inp->inp_vflag & INP_IPV4) == 0) {
1132                         error = EAFNOSUPPORT;
1133                         goto out;
1134                 }
1135                 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1136                         error = EISCONN;
1137                         goto out;
1138                 }
1139                 in6_sin6_2_sin(&sin, sin6);
1140                 inp->inp_vflag |= INP_IPV4;
1141                 inp->inp_vflag &= ~INP_IPV6;
1142                 error = prison_remote_ip4(td->td_ucred, &sin.sin_addr);
1143                 if (error != 0)
1144                         goto out;
1145                 INP_HASH_WLOCK(pcbinfo);
1146                 error = in_pcbconnect(inp, (struct sockaddr *)&sin,
1147                     td->td_ucred);
1148                 INP_HASH_WUNLOCK(pcbinfo);
1149                 if (error == 0)
1150                         soisconnected(so);
1151                 goto out;
1152         } else {
1153                 if ((inp->inp_vflag & INP_IPV6) == 0) {
1154                         error = EAFNOSUPPORT;
1155                         goto out;
1156                 }
1157         }
1158 #endif
1159         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1160                 error = EISCONN;
1161                 goto out;
1162         }
1163         inp->inp_vflag &= ~INP_IPV4;
1164         inp->inp_vflag |= INP_IPV6;
1165         error = prison_remote_ip6(td->td_ucred, &sin6->sin6_addr);
1166         if (error != 0)
1167                 goto out;
1168         INP_HASH_WLOCK(pcbinfo);
1169         error = in6_pcbconnect(inp, nam, td->td_ucred);
1170         INP_HASH_WUNLOCK(pcbinfo);
1171         if (error == 0)
1172                 soisconnected(so);
1173 out:
1174         INP_WUNLOCK(inp);
1175         return (error);
1176 }
1177
1178 static void
1179 udp6_detach(struct socket *so)
1180 {
1181         struct inpcb *inp;
1182         struct inpcbinfo *pcbinfo;
1183         struct udpcb *up;
1184
1185         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1186         inp = sotoinpcb(so);
1187         KASSERT(inp != NULL, ("udp6_detach: inp == NULL"));
1188
1189         INP_INFO_WLOCK(pcbinfo);
1190         INP_WLOCK(inp);
1191         up = intoudpcb(inp);
1192         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1193         in_pcbdetach(inp);
1194         in_pcbfree(inp);
1195         INP_INFO_WUNLOCK(pcbinfo);
1196         udp_discardcb(up);
1197 }
1198
1199 static int
1200 udp6_disconnect(struct socket *so)
1201 {
1202         struct inpcb *inp;
1203         struct inpcbinfo *pcbinfo;
1204
1205         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1206         inp = sotoinpcb(so);
1207         KASSERT(inp != NULL, ("udp6_disconnect: inp == NULL"));
1208
1209         INP_WLOCK(inp);
1210 #ifdef INET
1211         if (inp->inp_vflag & INP_IPV4) {
1212                 struct pr_usrreqs *pru;
1213                 uint8_t nxt;
1214
1215                 nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
1216                     IPPROTO_UDP : IPPROTO_UDPLITE;
1217                 INP_WUNLOCK(inp);
1218                 pru = inetsw[ip_protox[nxt]].pr_usrreqs;
1219                 (void)(*pru->pru_disconnect)(so);
1220                 return (0);
1221         }
1222 #endif
1223
1224         if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1225                 INP_WUNLOCK(inp);
1226                 return (ENOTCONN);
1227         }
1228
1229         INP_HASH_WLOCK(pcbinfo);
1230         in6_pcbdisconnect(inp);
1231         inp->in6p_laddr = in6addr_any;
1232         INP_HASH_WUNLOCK(pcbinfo);
1233         SOCK_LOCK(so);
1234         so->so_state &= ~SS_ISCONNECTED;                /* XXX */
1235         SOCK_UNLOCK(so);
1236         INP_WUNLOCK(inp);
1237         return (0);
1238 }
1239
1240 static int
1241 udp6_send(struct socket *so, int flags, struct mbuf *m,
1242     struct sockaddr *addr, struct mbuf *control, struct thread *td)
1243 {
1244         struct inpcb *inp;
1245         struct inpcbinfo *pcbinfo;
1246         int error = 0;
1247
1248         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1249         inp = sotoinpcb(so);
1250         KASSERT(inp != NULL, ("udp6_send: inp == NULL"));
1251
1252         INP_WLOCK(inp);
1253         if (addr) {
1254                 if (addr->sa_len != sizeof(struct sockaddr_in6)) {
1255                         error = EINVAL;
1256                         goto bad;
1257                 }
1258                 if (addr->sa_family != AF_INET6) {
1259                         error = EAFNOSUPPORT;
1260                         goto bad;
1261                 }
1262         }
1263
1264 #ifdef INET
1265         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
1266                 int hasv4addr;
1267                 struct sockaddr_in6 *sin6 = NULL;
1268
1269                 if (addr == NULL)
1270                         hasv4addr = (inp->inp_vflag & INP_IPV4);
1271                 else {
1272                         sin6 = (struct sockaddr_in6 *)addr;
1273                         hasv4addr = IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)
1274                             ? 1 : 0;
1275                 }
1276                 if (hasv4addr) {
1277                         struct pr_usrreqs *pru;
1278                         uint8_t nxt;
1279
1280                         nxt = (inp->inp_socket->so_proto->pr_protocol ==
1281                             IPPROTO_UDP) ? IPPROTO_UDP : IPPROTO_UDPLITE;
1282                         /*
1283                          * XXXRW: We release UDP-layer locks before calling
1284                          * udp_send() in order to avoid recursion.  However,
1285                          * this does mean there is a short window where inp's
1286                          * fields are unstable.  Could this lead to a
1287                          * potential race in which the factors causing us to
1288                          * select the UDPv4 output routine are invalidated?
1289                          */
1290                         INP_WUNLOCK(inp);
1291                         if (sin6)
1292                                 in6_sin6_2_sin_in_sock(addr);
1293                         pru = inetsw[ip_protox[nxt]].pr_usrreqs;
1294                         /* addr will just be freed in sendit(). */
1295                         return ((*pru->pru_send)(so, flags, m, addr, control,
1296                             td));
1297                 }
1298         }
1299 #endif
1300 #ifdef MAC
1301         mac_inpcb_create_mbuf(inp, m);
1302 #endif
1303         INP_HASH_WLOCK(pcbinfo);
1304         error = udp6_output(inp, m, addr, control, td);
1305         INP_HASH_WUNLOCK(pcbinfo);
1306         INP_WUNLOCK(inp);
1307         return (error);
1308
1309 bad:
1310         INP_WUNLOCK(inp);
1311         m_freem(m);
1312         return (error);
1313 }
1314
1315 struct pr_usrreqs udp6_usrreqs = {
1316         .pru_abort =            udp6_abort,
1317         .pru_attach =           udp6_attach,
1318         .pru_bind =             udp6_bind,
1319         .pru_connect =          udp6_connect,
1320         .pru_control =          in6_control,
1321         .pru_detach =           udp6_detach,
1322         .pru_disconnect =       udp6_disconnect,
1323         .pru_peeraddr =         in6_mapped_peeraddr,
1324         .pru_send =             udp6_send,
1325         .pru_shutdown =         udp_shutdown,
1326         .pru_sockaddr =         in6_mapped_sockaddr,
1327         .pru_soreceive =        soreceive_dgram,
1328         .pru_sosend =           sosend_dgram,
1329         .pru_sosetlabel =       in_pcbsosetlabel,
1330         .pru_close =            udp6_close
1331 };