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_ipsec.h"
  76 #include "opt_rss.h"
  77
  78 #include <sys/param.h>
  79 #include <sys/jail.h>
  80 #include <sys/kernel.h>
  81 #include <sys/lock.h>
  82 #include <sys/mbuf.h>
  83 #include <sys/priv.h>
  84 #include <sys/proc.h>
  85 #include <sys/protosw.h>
  86 #include <sys/sdt.h>
  87 #include <sys/signalvar.h>
  88 #include <sys/socket.h>
  89 #include <sys/socketvar.h>
  90 #include <sys/sx.h>
  91 #include <sys/sysctl.h>
  92 #include <sys/syslog.h>
  93 #include <sys/systm.h>
  94
  95 #include <net/if.h>
  96 #include <net/if_var.h>
  97 #include <net/if_types.h>
  98 #include <net/route.h>
  99 #include <net/rss_config.h>
 100
 101 #include <netinet/in.h>
 102 #include <netinet/in_kdtrace.h>
 103 #include <netinet/in_pcb.h>
 104 #include <netinet/in_systm.h>
 105 #include <netinet/in_var.h>
 106 #include <netinet/ip.h>
 107 #include <netinet/ip_icmp.h>
 108 #include <netinet/ip6.h>
 109 #include <netinet/icmp_var.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;
 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,
 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         m_adj(n, off + sizeof(struct udphdr));
 177
 178         so = inp->inp_socket;
 179         SOCKBUF_LOCK(&so->so_rcv);
 180         if (sbappendaddr_locked(&so->so_rcv, (struct sockaddr *)fromsa, n,
 181             opts) == 0) {
 182                 SOCKBUF_UNLOCK(&so->so_rcv);
 183                 m_freem(n);
 184                 if (opts)
 185                         m_freem(opts);
 186                 UDPSTAT_INC(udps_fullsock);
 187         } else
 188                 sorwakeup_locked(so);
 189         return (0);
 190 }
 191
 192 int
 193 udp6_input(struct mbuf **mp, int *offp, int proto)
 194 {
 195         struct mbuf *m = *mp;
 196         struct ifnet *ifp;
 197         struct ip6_hdr *ip6;
 198         struct udphdr *uh;
 199         struct inpcb *inp;
 200         struct inpcbinfo *pcbinfo;
 201         struct udpcb *up;
 202         int off = *offp;
 203         int cscov_partial;
 204         int plen, ulen;
 205         struct sockaddr_in6 fromsa;
 206         struct m_tag *fwd_tag;
 207         uint16_t uh_sum;
 208         uint8_t nxt;
 209
 210         ifp = m->m_pkthdr.rcvif;
 211         ip6 = mtod(m, struct ip6_hdr *);
 212
 213 #ifndef PULLDOWN_TEST
 214         IP6_EXTHDR_CHECK(m, off, sizeof(struct udphdr), IPPROTO_DONE);
 215         ip6 = mtod(m, struct ip6_hdr *);
 216         uh = (struct udphdr *)((caddr_t)ip6 + off);
 217 #else
 218         IP6_EXTHDR_GET(uh, struct udphdr *, m, off, sizeof(*uh));
 219         if (!uh)
 220                 return (IPPROTO_DONE);
 221 #endif
 222
 223         UDPSTAT_INC(udps_ipackets);
 224
 225         /*
 226          * Destination port of 0 is illegal, based on RFC768.
 227          */
 228         if (uh->uh_dport == 0)
 229                 goto badunlocked;
 230
 231         plen = ntohs(ip6->ip6_plen) - off + sizeof(*ip6);
 232         ulen = ntohs((u_short)uh->uh_ulen);
 233
 234         nxt = proto;
 235         cscov_partial = (nxt == IPPROTO_UDPLITE) ? 1 : 0;
 236         if (nxt == IPPROTO_UDPLITE) {
 237                 /* Zero means checksum over the complete packet. */
 238                 if (ulen == 0)
 239                         ulen = plen;
 240                 if (ulen == plen)
 241                         cscov_partial = 0;
 242                 if ((ulen < sizeof(struct udphdr)) || (ulen > plen)) {
 243                         /* XXX: What is the right UDPLite MIB counter? */
 244                         goto badunlocked;
 245                 }
 246                 if (uh->uh_sum == 0) {
 247                         /* XXX: What is the right UDPLite MIB counter? */
 248                         goto badunlocked;
 249                 }
 250         } else {
 251                 if ((ulen < sizeof(struct udphdr)) || (plen != ulen)) {
 252                         UDPSTAT_INC(udps_badlen);
 253                         goto badunlocked;
 254                 }
 255                 if (uh->uh_sum == 0) {
 256                         UDPSTAT_INC(udps_nosum);
 257                         goto badunlocked;
 258                 }
 259         }
 260
 261         if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID_IPV6) &&
 262             !cscov_partial) {
 263                 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
 264                         uh_sum = m->m_pkthdr.csum_data;
 265                 else
 266                         uh_sum = in6_cksum_pseudo(ip6, ulen, nxt,
 267                             m->m_pkthdr.csum_data);
 268                 uh_sum ^= 0xffff;
 269         } else
 270                 uh_sum = in6_cksum_partial(m, nxt, off, plen, ulen);
 271
 272         if (uh_sum != 0) {
 273                 UDPSTAT_INC(udps_badsum);
 274                 goto badunlocked;
 275         }
 276
 277         /*
 278          * Construct sockaddr format source address.
 279          */
 280         init_sin6(&fromsa, m);
 281         fromsa.sin6_port = uh->uh_sport;
 282
 283         pcbinfo = udp_get_inpcbinfo(nxt);
 284         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 285                 struct inpcb *last;
 286                 struct inpcbhead *pcblist;
 287                 struct ip6_moptions *imo;
 288
 289                 INP_INFO_RLOCK(pcbinfo);
 290                 /*
 291                  * In the event that laddr should be set to the link-local
 292                  * address (this happens in RIPng), the multicast address
 293                  * specified in the received packet will not match laddr.  To
 294                  * handle this situation, matching is relaxed if the
 295                  * receiving interface is the same as one specified in the
 296                  * socket and if the destination multicast address matches
 297                  * one of the multicast groups specified in the socket.
 298                  */
 299
 300                 /*
 301                  * KAME note: traditionally we dropped udpiphdr from mbuf
 302                  * here.  We need udphdr for IPsec processing so we do that
 303                  * later.
 304                  */
 305                 pcblist = udp_get_pcblist(nxt);
 306                 last = NULL;
 307                 LIST_FOREACH(inp, pcblist, inp_list) {
 308                         if ((inp->inp_vflag & INP_IPV6) == 0)
 309                                 continue;
 310                         if (inp->inp_lport != uh->uh_dport)
 311                                 continue;
 312                         if (inp->inp_fport != 0 &&
 313                             inp->inp_fport != uh->uh_sport)
 314                                 continue;
 315                         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
 316                                 if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr,
 317                                                         &ip6->ip6_dst))
 318                                         continue;
 319                         }
 320                         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 321                                 if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr,
 322                                                         &ip6->ip6_src) ||
 323                                     inp->inp_fport != uh->uh_sport)
 324                                         continue;
 325                         }
 326
 327                         /*
 328                          * XXXRW: Because we weren't holding either the inpcb
 329                          * or the hash lock when we checked for a match
 330                          * before, we should probably recheck now that the
 331                          * inpcb lock is (supposed to be) held.
 332                          */
 333
 334                         /*
 335                          * Handle socket delivery policy for any-source
 336                          * and source-specific multicast. [RFC3678]
 337                          */
 338                         imo = inp->in6p_moptions;
 339                         if (imo && IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 340                                 struct sockaddr_in6      mcaddr;
 341                                 int                      blocked;
 342
 343                                 INP_RLOCK(inp);
 344
 345                                 bzero(&mcaddr, sizeof(struct sockaddr_in6));
 346                                 mcaddr.sin6_len = sizeof(struct sockaddr_in6);
 347                                 mcaddr.sin6_family = AF_INET6;
 348                                 mcaddr.sin6_addr = ip6->ip6_dst;
 349
 350                                 blocked = im6o_mc_filter(imo, ifp,
 351                                         (struct sockaddr *)&mcaddr,
 352                                         (struct sockaddr *)&fromsa);
 353                                 if (blocked != MCAST_PASS) {
 354                                         if (blocked == MCAST_NOTGMEMBER)
 355                                                 IP6STAT_INC(ip6s_notmember);
 356                                         if (blocked == MCAST_NOTSMEMBER ||
 357                                             blocked == MCAST_MUTED)
 358                                                 UDPSTAT_INC(udps_filtermcast);
 359                                         INP_RUNLOCK(inp); /* XXX */
 360                                         continue;
 361                                 }
 362
 363                                 INP_RUNLOCK(inp);
 364                         }
 365                         if (last != NULL) {
 366                                 struct mbuf *n;
 367
 368                                 if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
 369                                         INP_RLOCK(last);
 370                                         UDP_PROBE(receive, NULL, last, ip6,
 371                                             last, uh);
 372                                         if (udp6_append(last, n, off, &fromsa))
 373                                                 goto inp_lost;
 374                                         INP_RUNLOCK(last);
 375                                 }
 376                         }
 377                         last = inp;
 378                         /*
 379                          * Don't look for additional matches if this one does
 380                          * not have either the SO_REUSEPORT or SO_REUSEADDR
 381                          * socket options set.  This heuristic avoids
 382                          * searching through all pcbs in the common case of a
 383                          * non-shared port.  It assumes that an application
 384                          * will never clear these options after setting them.
 385                          */
 386                         if ((last->inp_socket->so_options &
 387                              (SO_REUSEPORT|SO_REUSEADDR)) == 0)
 388                                 break;
 389                 }
 390
 391                 if (last == NULL) {
 392                         /*
 393                          * No matching pcb found; discard datagram.  (No need
 394                          * to send an ICMP Port Unreachable for a broadcast
 395                          * or multicast datgram.)
 396                          */
 397                         UDPSTAT_INC(udps_noport);
 398                         UDPSTAT_INC(udps_noportmcast);
 399                         goto badheadlocked;
 400                 }
 401                 INP_RLOCK(last);
 402                 INP_INFO_RUNLOCK(pcbinfo);
 403                 UDP_PROBE(receive, NULL, last, ip6, last, uh);
 404                 if (udp6_append(last, m, off, &fromsa) == 0)
 405                         INP_RUNLOCK(last);
 406         inp_lost:
 407                 return (IPPROTO_DONE);
 408         }
 409         /*
 410          * Locate pcb for datagram.
 411          */
 412
 413         /*
 414          * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
 415          */
 416         if ((m->m_flags & M_IP6_NEXTHOP) &&
 417             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 418                 struct sockaddr_in6 *next_hop6;
 419
 420                 next_hop6 = (struct sockaddr_in6 *)(fwd_tag + 1);
 421
 422                 /*
 423                  * Transparently forwarded. Pretend to be the destination.
 424                  * Already got one like this?
 425                  */
 426                 inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_src,
 427                     uh->uh_sport, &ip6->ip6_dst, uh->uh_dport,
 428                     INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif, m);
 429                 if (!inp) {
 430                         /*
 431                          * It's new.  Try to find the ambushing socket.
 432                          * Because we've rewritten the destination address,
 433                          * any hardware-generated hash is ignored.
 434                          */
 435                         inp = in6_pcblookup(pcbinfo, &ip6->ip6_src,
 436                             uh->uh_sport, &next_hop6->sin6_addr,
 437                             next_hop6->sin6_port ? htons(next_hop6->sin6_port) :
 438                             uh->uh_dport, INPLOOKUP_WILDCARD |
 439                             INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif);
 440                 }
 441                 /* Remove the tag from the packet. We don't need it anymore. */
 442                 m_tag_delete(m, fwd_tag);
 443                 m->m_flags &= ~M_IP6_NEXTHOP;
 444         } else
 445                 inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_src,
 446                     uh->uh_sport, &ip6->ip6_dst, uh->uh_dport,
 447                     INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB,
 448                     m->m_pkthdr.rcvif, m);
 449         if (inp == NULL) {
 450                 if (udp_log_in_vain) {
 451                         char ip6bufs[INET6_ADDRSTRLEN];
 452                         char ip6bufd[INET6_ADDRSTRLEN];
 453
 454                         log(LOG_INFO,
 455                             "Connection attempt to UDP [%s]:%d from [%s]:%d\n",
 456                             ip6_sprintf(ip6bufd, &ip6->ip6_dst),
 457                             ntohs(uh->uh_dport),
 458                             ip6_sprintf(ip6bufs, &ip6->ip6_src),
 459                             ntohs(uh->uh_sport));
 460                 }
 461                 UDPSTAT_INC(udps_noport);
 462                 if (m->m_flags & M_MCAST) {
 463                         printf("UDP6: M_MCAST is set in a unicast packet.\n");
 464                         UDPSTAT_INC(udps_noportmcast);
 465                         goto badunlocked;
 466                 }
 467                 if (V_udp_blackhole)
 468                         goto badunlocked;
 469                 if (badport_bandlim(BANDLIM_ICMP6_UNREACH) < 0)
 470                         goto badunlocked;
 471                 icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
 472                 return (IPPROTO_DONE);
 473         }
 474         INP_RLOCK_ASSERT(inp);
 475         up = intoudpcb(inp);
 476         if (cscov_partial) {
 477                 if (up->u_rxcslen == 0 || up->u_rxcslen > ulen) {
 478                         INP_RUNLOCK(inp);
 479                         m_freem(m);
 480                         return (IPPROTO_DONE);
 481                 }
 482         }
 483         UDP_PROBE(receive, NULL, inp, ip6, inp, uh);
 484         if (udp6_append(inp, m, off, &fromsa) == 0)
 485                 INP_RUNLOCK(inp);
 486         return (IPPROTO_DONE);
 487
 488 badheadlocked:
 489         INP_INFO_RUNLOCK(pcbinfo);
 490 badunlocked:
 491         if (m)
 492                 m_freem(m);
 493         return (IPPROTO_DONE);
 494 }
 495
 496 static void
 497 udp6_common_ctlinput(int cmd, struct sockaddr *sa, void *d,
 498     struct inpcbinfo *pcbinfo)
 499 {
 500         struct udphdr uh;
 501         struct ip6_hdr *ip6;
 502         struct mbuf *m;
 503         int off = 0;
 504         struct ip6ctlparam *ip6cp = NULL;
 505         const struct sockaddr_in6 *sa6_src = NULL;
 506         void *cmdarg;
 507         struct inpcb *(*notify)(struct inpcb *, int) = udp_notify;
 508         struct udp_portonly {
 509                 u_int16_t uh_sport;
 510                 u_int16_t uh_dport;
 511         } *uhp;
 512
 513         if (sa->sa_family != AF_INET6 ||
 514             sa->sa_len != sizeof(struct sockaddr_in6))
 515                 return;
 516
 517         if ((unsigned)cmd >= PRC_NCMDS)
 518                 return;
 519         if (PRC_IS_REDIRECT(cmd))
 520                 notify = in6_rtchange, d = NULL;
 521         else if (cmd == PRC_HOSTDEAD)
 522                 d = NULL;
 523         else if (inet6ctlerrmap[cmd] == 0)
 524                 return;
 525
 526         /* if the parameter is from icmp6, decode it. */
 527         if (d != NULL) {
 528                 ip6cp = (struct ip6ctlparam *)d;
 529                 m = ip6cp->ip6c_m;
 530                 ip6 = ip6cp->ip6c_ip6;
 531                 off = ip6cp->ip6c_off;
 532                 cmdarg = ip6cp->ip6c_cmdarg;
 533                 sa6_src = ip6cp->ip6c_src;
 534         } else {
 535                 m = NULL;
 536                 ip6 = NULL;
 537                 cmdarg = NULL;
 538                 sa6_src = &sa6_any;
 539         }
 540
 541         if (ip6) {
 542                 /*
 543                  * XXX: We assume that when IPV6 is non NULL,
 544                  * M and OFF are valid.
 545                  */
 546
 547                 /* Check if we can safely examine src and dst ports. */
 548                 if (m->m_pkthdr.len < off + sizeof(*uhp))
 549                         return;
 550
 551                 bzero(&uh, sizeof(uh));
 552                 m_copydata(m, off, sizeof(*uhp), (caddr_t)&uh);
 553
 554                 if (!PRC_IS_REDIRECT(cmd)) {
 555                         /* Check to see if its tunneled */
 556                         struct inpcb *inp;
 557                         inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_dst,
 558                             uh.uh_dport, &ip6->ip6_src, uh.uh_sport,
 559                             INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB,
 560                             m->m_pkthdr.rcvif, m);
 561                         if (inp != NULL) {
 562                                 struct udpcb *up;
 563
 564                                 up = intoudpcb(inp);
 565                                 if (up->u_icmp_func) {
 566                                         /* Yes it is. */
 567                                         INP_RUNLOCK(inp);
 568                                         (*up->u_icmp_func)(cmd, (struct sockaddr *)ip6cp->ip6c_src,
 569                                               d, up->u_tun_ctx);
 570                                         return;
 571                                 } else {
 572                                         /* Can't find it. */
 573                                         INP_RUNLOCK(inp);
 574                                 }
 575                         }
 576                 }
 577                 (void)in6_pcbnotify(pcbinfo, sa, uh.uh_dport,
 578                     (struct sockaddr *)ip6cp->ip6c_src, uh.uh_sport, cmd,
 579                     cmdarg, notify);
 580         } else
 581                 (void)in6_pcbnotify(pcbinfo, sa, 0,
 582                     (const struct sockaddr *)sa6_src, 0, cmd, cmdarg, notify);
 583 }
 584
 585 void
 586 udp6_ctlinput(int cmd, struct sockaddr *sa, void *d)
 587 {
 588
 589         return (udp6_common_ctlinput(cmd, sa, d, &V_udbinfo));
 590 }
 591
 592 void
 593 udplite6_ctlinput(int cmd, struct sockaddr *sa, void *d)
 594 {
 595
 596         return (udp6_common_ctlinput(cmd, sa, d, &V_ulitecbinfo));
 597 }
 598
 599 static int
 600 udp6_getcred(SYSCTL_HANDLER_ARGS)
 601 {
 602         struct xucred xuc;
 603         struct sockaddr_in6 addrs[2];
 604         struct inpcb *inp;
 605         int error;
 606
 607         error = priv_check(req->td, PRIV_NETINET_GETCRED);
 608         if (error)
 609                 return (error);
 610
 611         if (req->newlen != sizeof(addrs))
 612                 return (EINVAL);
 613         if (req->oldlen != sizeof(struct xucred))
 614                 return (EINVAL);
 615         error = SYSCTL_IN(req, addrs, sizeof(addrs));
 616         if (error)
 617                 return (error);
 618         if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 ||
 619             (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) {
 620                 return (error);
 621         }
 622         inp = in6_pcblookup(&V_udbinfo, &addrs[1].sin6_addr,
 623             addrs[1].sin6_port, &addrs[0].sin6_addr, addrs[0].sin6_port,
 624             INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 625         if (inp != NULL) {
 626                 INP_RLOCK_ASSERT(inp);
 627                 if (inp->inp_socket == NULL)
 628                         error = ENOENT;
 629                 if (error == 0)
 630                         error = cr_canseesocket(req->td->td_ucred,
 631                             inp->inp_socket);
 632                 if (error == 0)
 633                         cru2x(inp->inp_cred, &xuc);
 634                 INP_RUNLOCK(inp);
 635         } else
 636                 error = ENOENT;
 637         if (error == 0)
 638                 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
 639         return (error);
 640 }
 641
 642 SYSCTL_PROC(_net_inet6_udp6, OID_AUTO, getcred, CTLTYPE_OPAQUE|CTLFLAG_RW, 0,
 643     0, udp6_getcred, "S,xucred", "Get the xucred of a UDP6 connection");
 644
 645 static int
 646 udp6_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr6,
 647     struct mbuf *control, struct thread *td)
 648 {
 649         u_int32_t ulen = m->m_pkthdr.len;
 650         u_int32_t plen = sizeof(struct udphdr) + ulen;
 651         struct ip6_hdr *ip6;
 652         struct udphdr *udp6;
 653         struct in6_addr *laddr, *faddr, in6a;
 654         struct sockaddr_in6 *sin6 = NULL;
 655         int cscov_partial = 0;
 656         int scope_ambiguous = 0;
 657         u_short fport;
 658         int error = 0;
 659         uint8_t nxt;
 660         uint16_t cscov = 0;
 661         struct ip6_pktopts *optp, opt;
 662         int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
 663         int flags;
 664         struct sockaddr_in6 tmp;
 665
 666         INP_WLOCK_ASSERT(inp);
 667         INP_HASH_WLOCK_ASSERT(inp->inp_pcbinfo);
 668
 669         if (addr6) {
 670                 /* addr6 has been validated in udp6_send(). */
 671                 sin6 = (struct sockaddr_in6 *)addr6;
 672
 673                 /* protect *sin6 from overwrites */
 674                 tmp = *sin6;
 675                 sin6 = &tmp;
 676
 677                 /*
 678                  * Application should provide a proper zone ID or the use of
 679                  * default zone IDs should be enabled.  Unfortunately, some
 680                  * applications do not behave as it should, so we need a
 681                  * workaround.  Even if an appropriate ID is not determined,
 682                  * we'll see if we can determine the outgoing interface.  If we
 683                  * can, determine the zone ID based on the interface below.
 684                  */
 685                 if (sin6->sin6_scope_id == 0 && !V_ip6_use_defzone)
 686                         scope_ambiguous = 1;
 687                 if ((error = sa6_embedscope(sin6, V_ip6_use_defzone)) != 0)
 688                         return (error);
 689         }
 690
 691         nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
 692             IPPROTO_UDP : IPPROTO_UDPLITE;
 693         if (control) {
 694                 if ((error = ip6_setpktopts(control, &opt,
 695                     inp->in6p_outputopts, td->td_ucred, nxt)) != 0)
 696                         goto release;
 697                 optp = &opt;
 698         } else
 699                 optp = inp->in6p_outputopts;
 700
 701         if (sin6) {
 702                 faddr = &sin6->sin6_addr;
 703
 704                 /*
 705                  * Since we saw no essential reason for calling in_pcbconnect,
 706                  * we get rid of such kind of logic, and call in6_selectsrc
 707                  * and in6_pcbsetport in order to fill in the local address
 708                  * and the local port.
 709                  */
 710                 if (sin6->sin6_port == 0) {
 711                         error = EADDRNOTAVAIL;
 712                         goto release;
 713                 }
 714
 715                 if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 716                         /* how about ::ffff:0.0.0.0 case? */
 717                         error = EISCONN;
 718                         goto release;
 719                 }
 720
 721                 fport = sin6->sin6_port; /* allow 0 port */
 722
 723                 if (IN6_IS_ADDR_V4MAPPED(faddr)) {
 724                         if ((inp->inp_flags & IN6P_IPV6_V6ONLY)) {
 725                                 /*
 726                                  * I believe we should explicitly discard the
 727                                  * packet when mapped addresses are disabled,
 728                                  * rather than send the packet as an IPv6 one.
 729                                  * If we chose the latter approach, the packet
 730                                  * might be sent out on the wire based on the
 731                                  * default route, the situation which we'd
 732                                  * probably want to avoid.
 733                                  * (20010421 jinmei@kame.net)
 734                                  */
 735                                 error = EINVAL;
 736                                 goto release;
 737                         }
 738                         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
 739                             !IN6_IS_ADDR_V4MAPPED(&inp->in6p_laddr)) {
 740                                 /*
 741                                  * when remote addr is an IPv4-mapped address,
 742                                  * local addr should not be an IPv6 address,
 743                                  * since you cannot determine how to map IPv6
 744                                  * source address to IPv4.
 745                                  */
 746                                 error = EINVAL;
 747                                 goto release;
 748                         }
 749
 750                         af = AF_INET;
 751                 }
 752
 753                 if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
 754                         error = in6_selectsrc_socket(sin6, optp, inp,
 755                             td->td_ucred, scope_ambiguous, &in6a, NULL);
 756                         if (error)
 757                                 goto release;
 758                         laddr = &in6a;
 759                 } else
 760                         laddr = &inp->in6p_laddr;       /* XXX */
 761                 if (laddr == NULL) {
 762                         if (error == 0)
 763                                 error = EADDRNOTAVAIL;
 764                         goto release;
 765                 }
 766                 if (inp->inp_lport == 0 &&
 767                     (error = in6_pcbsetport(laddr, inp, td->td_ucred)) != 0) {
 768                         /* Undo an address bind that may have occurred. */
 769                         inp->in6p_laddr = in6addr_any;
 770                         goto release;
 771                 }
 772         } else {
 773                 if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 774                         error = ENOTCONN;
 775                         goto release;
 776                 }
 777                 if (IN6_IS_ADDR_V4MAPPED(&inp->in6p_faddr)) {
 778                         if ((inp->inp_flags & IN6P_IPV6_V6ONLY)) {
 779                                 /*
 780                                  * XXX: this case would happen when the
 781                                  * application sets the V6ONLY flag after
 782                                  * connecting the foreign address.
 783                                  * Such applications should be fixed,
 784                                  * so we bark here.
 785                                  */
 786                                 log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
 787                                     "option was set for a connected socket\n");
 788                                 error = EINVAL;
 789                                 goto release;
 790                         } else
 791                                 af = AF_INET;
 792                 }
 793                 laddr = &inp->in6p_laddr;
 794                 faddr = &inp->in6p_faddr;
 795                 fport = inp->inp_fport;
 796         }
 797
 798         if (af == AF_INET)
 799                 hlen = sizeof(struct ip);
 800
 801         /*
 802          * Calculate data length and get a mbuf
 803          * for UDP and IP6 headers.
 804          */
 805         M_PREPEND(m, hlen + sizeof(struct udphdr), M_NOWAIT);
 806         if (m == NULL) {
 807                 error = ENOBUFS;
 808                 goto release;
 809         }
 810
 811         /*
 812          * Stuff checksum and output datagram.
 813          */
 814         udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
 815         udp6->uh_sport = inp->inp_lport; /* lport is always set in the PCB */
 816         udp6->uh_dport = fport;
 817         if (nxt == IPPROTO_UDPLITE) {
 818                 struct udpcb *up;
 819
 820                 up = intoudpcb(inp);
 821                 cscov = up->u_txcslen;
 822                 if (cscov >= plen)
 823                         cscov = 0;
 824                 udp6->uh_ulen = htons(cscov);
 825                 /*
 826                  * For UDP-Lite, checksum coverage length of zero means
 827                  * the entire UDPLite packet is covered by the checksum.
 828                  */
 829                 cscov_partial = (cscov == 0) ? 0 : 1;
 830         } else if (plen <= 0xffff)
 831                 udp6->uh_ulen = htons((u_short)plen);
 832         else
 833                 udp6->uh_ulen = 0;
 834         udp6->uh_sum = 0;
 835
 836         switch (af) {
 837         case AF_INET6:
 838                 ip6 = mtod(m, struct ip6_hdr *);
 839                 ip6->ip6_flow   = inp->inp_flow & IPV6_FLOWINFO_MASK;
 840                 ip6->ip6_vfc    &= ~IPV6_VERSION_MASK;
 841                 ip6->ip6_vfc    |= IPV6_VERSION;
 842                 ip6->ip6_plen   = htons((u_short)plen);
 843                 ip6->ip6_nxt    = nxt;
 844                 ip6->ip6_hlim   = in6_selecthlim(inp, NULL);
 845                 ip6->ip6_src    = *laddr;
 846                 ip6->ip6_dst    = *faddr;
 847
 848                 if (cscov_partial) {
 849                         if ((udp6->uh_sum = in6_cksum_partial(m, nxt,
 850                             sizeof(struct ip6_hdr), plen, cscov)) == 0)
 851                                 udp6->uh_sum = 0xffff;
 852                 } else {
 853                         udp6->uh_sum = in6_cksum_pseudo(ip6, plen, nxt, 0);
 854                         m->m_pkthdr.csum_flags = CSUM_UDP_IPV6;
 855                         m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
 856                 }
 857
 858 #ifdef  RSS
 859                 {
 860                         uint32_t hash_val, hash_type;
 861                         uint8_t pr;
 862
 863                         pr = inp->inp_socket->so_proto->pr_protocol;
 864                         /*
 865                          * Calculate an appropriate RSS hash for UDP and
 866                          * UDP Lite.
 867                          *
 868                          * The called function will take care of figuring out
 869                          * whether a 2-tuple or 4-tuple hash is required based
 870                          * on the currently configured scheme.
 871                          *
 872                          * Later later on connected socket values should be
 873                          * cached in the inpcb and reused, rather than constantly
 874                          * re-calculating it.
 875                          *
 876                          * UDP Lite is a different protocol number and will
 877                          * likely end up being hashed as a 2-tuple until
 878                          * RSS / NICs grow UDP Lite protocol awareness.
 879                          */
 880                         if (rss_proto_software_hash_v6(faddr, laddr, fport,
 881                             inp->inp_lport, pr, &hash_val, &hash_type) == 0) {
 882                                 m->m_pkthdr.flowid = hash_val;
 883                                 M_HASHTYPE_SET(m, hash_type);
 884                         }
 885                 }
 886 #endif
 887                 flags = 0;
 888 #ifdef  RSS
 889                 /*
 890                  * Don't override with the inp cached flowid.
 891                  *
 892                  * Until the whole UDP path is vetted, it may actually
 893                  * be incorrect.
 894                  */
 895                 flags |= IP_NODEFAULTFLOWID;
 896 #endif
 897
 898                 UDP_PROBE(send, NULL, inp, ip6, inp, udp6);
 899                 UDPSTAT_INC(udps_opackets);
 900                 error = ip6_output(m, optp, &inp->inp_route6, flags,
 901                     inp->in6p_moptions, NULL, inp);
 902                 break;
 903         case AF_INET:
 904                 error = EAFNOSUPPORT;
 905                 goto release;
 906         }
 907         goto releaseopt;
 908
 909 release:
 910         m_freem(m);
 911
 912 releaseopt:
 913         if (control) {
 914                 ip6_clearpktopts(&opt, -1);
 915                 m_freem(control);
 916         }
 917         return (error);
 918 }
 919
 920 static void
 921 udp6_abort(struct socket *so)
 922 {
 923         struct inpcb *inp;
 924         struct inpcbinfo *pcbinfo;
 925
 926         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
 927         inp = sotoinpcb(so);
 928         KASSERT(inp != NULL, ("udp6_abort: inp == NULL"));
 929
 930         INP_WLOCK(inp);
 931 #ifdef INET
 932         if (inp->inp_vflag & INP_IPV4) {
 933                 struct pr_usrreqs *pru;
 934                 uint8_t nxt;
 935
 936                 nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
 937                     IPPROTO_UDP : IPPROTO_UDPLITE;
 938                 INP_WUNLOCK(inp);
 939                 pru = inetsw[ip_protox[nxt]].pr_usrreqs;
 940                 (*pru->pru_abort)(so);
 941                 return;
 942         }
 943 #endif
 944
 945         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 946                 INP_HASH_WLOCK(pcbinfo);
 947                 in6_pcbdisconnect(inp);
 948                 inp->in6p_laddr = in6addr_any;
 949                 INP_HASH_WUNLOCK(pcbinfo);
 950                 soisdisconnected(so);
 951         }
 952         INP_WUNLOCK(inp);
 953 }
 954
 955 static int
 956 udp6_attach(struct socket *so, int proto, struct thread *td)
 957 {
 958         struct inpcb *inp;
 959         struct inpcbinfo *pcbinfo;
 960         int error;
 961
 962         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
 963         inp = sotoinpcb(so);
 964         KASSERT(inp == NULL, ("udp6_attach: inp != NULL"));
 965
 966         if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
 967                 error = soreserve(so, udp_sendspace, udp_recvspace);
 968                 if (error)
 969                         return (error);
 970         }
 971         INP_INFO_WLOCK(pcbinfo);
 972         error = in_pcballoc(so, pcbinfo);
 973         if (error) {
 974                 INP_INFO_WUNLOCK(pcbinfo);
 975                 return (error);
 976         }
 977         inp = (struct inpcb *)so->so_pcb;
 978         inp->inp_vflag |= INP_IPV6;
 979         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
 980                 inp->inp_vflag |= INP_IPV4;
 981         inp->in6p_hops = -1;    /* use kernel default */
 982         inp->in6p_cksum = -1;   /* just to be sure */
 983         /*
 984          * XXX: ugly!!
 985          * IPv4 TTL initialization is necessary for an IPv6 socket as well,
 986          * because the socket may be bound to an IPv6 wildcard address,
 987          * which may match an IPv4-mapped IPv6 address.
 988          */
 989         inp->inp_ip_ttl = V_ip_defttl;
 990
 991         error = udp_newudpcb(inp);
 992         if (error) {
 993                 in_pcbdetach(inp);
 994                 in_pcbfree(inp);
 995                 INP_INFO_WUNLOCK(pcbinfo);
 996                 return (error);
 997         }
 998         INP_WUNLOCK(inp);
 999         INP_INFO_WUNLOCK(pcbinfo);
1000         return (0);
1001 }
1002
1003 static int
1004 udp6_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1005 {
1006         struct inpcb *inp;
1007         struct inpcbinfo *pcbinfo;
1008         int error;
1009         u_char vflagsav;
1010
1011         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1012         inp = sotoinpcb(so);
1013         KASSERT(inp != NULL, ("udp6_bind: inp == NULL"));
1014
1015         INP_WLOCK(inp);
1016         INP_HASH_WLOCK(pcbinfo);
1017         vflagsav = inp->inp_vflag;
1018         inp->inp_vflag &= ~INP_IPV4;
1019         inp->inp_vflag |= INP_IPV6;
1020         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
1021                 struct sockaddr_in6 *sin6_p;
1022
1023                 sin6_p = (struct sockaddr_in6 *)nam;
1024
1025                 if (IN6_IS_ADDR_UNSPECIFIED(&sin6_p->sin6_addr))
1026                         inp->inp_vflag |= INP_IPV4;
1027 #ifdef INET
1028                 else if (IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {
1029                         struct sockaddr_in sin;
1030
1031                         in6_sin6_2_sin(&sin, sin6_p);
1032                         inp->inp_vflag |= INP_IPV4;
1033                         inp->inp_vflag &= ~INP_IPV6;
1034                         error = in_pcbbind(inp, (struct sockaddr *)&sin,
1035                             td->td_ucred);
1036                         goto out;
1037                 }
1038 #endif
1039         }
1040
1041         error = in6_pcbbind(inp, nam, td->td_ucred);
1042 #ifdef INET
1043 out:
1044 #endif
1045         if (error != 0)
1046                 inp->inp_vflag = vflagsav;
1047         INP_HASH_WUNLOCK(pcbinfo);
1048         INP_WUNLOCK(inp);
1049         return (error);
1050 }
1051
1052 static void
1053 udp6_close(struct socket *so)
1054 {
1055         struct inpcb *inp;
1056         struct inpcbinfo *pcbinfo;
1057
1058         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1059         inp = sotoinpcb(so);
1060         KASSERT(inp != NULL, ("udp6_close: inp == NULL"));
1061
1062         INP_WLOCK(inp);
1063 #ifdef INET
1064         if (inp->inp_vflag & INP_IPV4) {
1065                 struct pr_usrreqs *pru;
1066                 uint8_t nxt;
1067
1068                 nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
1069                     IPPROTO_UDP : IPPROTO_UDPLITE;
1070                 INP_WUNLOCK(inp);
1071                 pru = inetsw[ip_protox[nxt]].pr_usrreqs;
1072                 (*pru->pru_disconnect)(so);
1073                 return;
1074         }
1075 #endif
1076         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1077                 INP_HASH_WLOCK(pcbinfo);
1078                 in6_pcbdisconnect(inp);
1079                 inp->in6p_laddr = in6addr_any;
1080                 INP_HASH_WUNLOCK(pcbinfo);
1081                 soisdisconnected(so);
1082         }
1083         INP_WUNLOCK(inp);
1084 }
1085
1086 static int
1087 udp6_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1088 {
1089         struct inpcb *inp;
1090         struct inpcbinfo *pcbinfo;
1091         struct sockaddr_in6 *sin6;
1092         int error;
1093         u_char vflagsav;
1094
1095         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1096         inp = sotoinpcb(so);
1097         sin6 = (struct sockaddr_in6 *)nam;
1098         KASSERT(inp != NULL, ("udp6_connect: inp == NULL"));
1099
1100         /*
1101          * XXXRW: Need to clarify locking of v4/v6 flags.
1102          */
1103         INP_WLOCK(inp);
1104 #ifdef INET
1105         if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
1106                 struct sockaddr_in sin;
1107
1108                 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
1109                         error = EINVAL;
1110                         goto out;
1111                 }
1112                 if ((inp->inp_vflag & INP_IPV4) == 0) {
1113                         error = EAFNOSUPPORT;
1114                         goto out;
1115                 }
1116                 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1117                         error = EISCONN;
1118                         goto out;
1119                 }
1120                 in6_sin6_2_sin(&sin, sin6);
1121                 error = prison_remote_ip4(td->td_ucred, &sin.sin_addr);
1122                 if (error != 0)
1123                         goto out;
1124                 vflagsav = inp->inp_vflag;
1125                 inp->inp_vflag |= INP_IPV4;
1126                 inp->inp_vflag &= ~INP_IPV6;
1127                 INP_HASH_WLOCK(pcbinfo);
1128                 error = in_pcbconnect(inp, (struct sockaddr *)&sin,
1129                     td->td_ucred);
1130                 INP_HASH_WUNLOCK(pcbinfo);
1131                 /*
1132                  * If connect succeeds, mark socket as connected. If
1133                  * connect fails and socket is unbound, reset inp_vflag
1134                  * field.
1135                  */
1136                 if (error == 0)
1137                         soisconnected(so);
1138                 else if (inp->inp_laddr.s_addr == INADDR_ANY &&
1139                     inp->inp_lport == 0)
1140                         inp->inp_vflag = vflagsav;
1141                 goto out;
1142         } else {
1143                 if ((inp->inp_vflag & INP_IPV6) == 0) {
1144                         error = EAFNOSUPPORT;
1145                         goto out;
1146                 }
1147         }
1148 #endif
1149         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1150                 error = EISCONN;
1151                 goto out;
1152         }
1153         error = prison_remote_ip6(td->td_ucred, &sin6->sin6_addr);
1154         if (error != 0)
1155                 goto out;
1156         vflagsav = inp->inp_vflag;
1157         inp->inp_vflag &= ~INP_IPV4;
1158         inp->inp_vflag |= INP_IPV6;
1159         INP_HASH_WLOCK(pcbinfo);
1160         error = in6_pcbconnect(inp, nam, td->td_ucred);
1161         INP_HASH_WUNLOCK(pcbinfo);
1162         /*
1163          * If connect succeeds, mark socket as connected. If
1164          * connect fails and socket is unbound, reset inp_vflag
1165          * field.
1166          */
1167         if (error == 0)
1168                 soisconnected(so);
1169         else if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
1170             inp->inp_lport == 0)
1171                 inp->inp_vflag = vflagsav;
1172 out:
1173         INP_WUNLOCK(inp);
1174         return (error);
1175 }
1176
1177 static void
1178 udp6_detach(struct socket *so)
1179 {
1180         struct inpcb *inp;
1181         struct inpcbinfo *pcbinfo;
1182         struct udpcb *up;
1183
1184         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1185         inp = sotoinpcb(so);
1186         KASSERT(inp != NULL, ("udp6_detach: inp == NULL"));
1187
1188         INP_INFO_WLOCK(pcbinfo);
1189         INP_WLOCK(inp);
1190         up = intoudpcb(inp);
1191         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1192         in_pcbdetach(inp);
1193         in_pcbfree(inp);
1194         INP_INFO_WUNLOCK(pcbinfo);
1195         udp_discardcb(up);
1196 }
1197
1198 static int
1199 udp6_disconnect(struct socket *so)
1200 {
1201         struct inpcb *inp;
1202         struct inpcbinfo *pcbinfo;
1203         int error;
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                 error = ENOTCONN;
1226                 goto out;
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 out:
1237         INP_WUNLOCK(inp);
1238         return (0);
1239 }
1240
1241 static int
1242 udp6_send(struct socket *so, int flags, struct mbuf *m,
1243     struct sockaddr *addr, struct mbuf *control, struct thread *td)
1244 {
1245         struct inpcb *inp;
1246         struct inpcbinfo *pcbinfo;
1247         int error = 0;
1248
1249         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1250         inp = sotoinpcb(so);
1251         KASSERT(inp != NULL, ("udp6_send: inp == NULL"));
1252
1253         INP_WLOCK(inp);
1254         if (addr) {
1255                 if (addr->sa_len != sizeof(struct sockaddr_in6)) {
1256                         error = EINVAL;
1257                         goto bad;
1258                 }
1259                 if (addr->sa_family != AF_INET6) {
1260                         error = EAFNOSUPPORT;
1261                         goto bad;
1262                 }
1263         }
1264
1265 #ifdef INET
1266         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
1267                 int hasv4addr;
1268                 struct sockaddr_in6 *sin6 = NULL;
1269
1270                 if (addr == NULL)
1271                         hasv4addr = (inp->inp_vflag & INP_IPV4);
1272                 else {
1273                         sin6 = (struct sockaddr_in6 *)addr;
1274                         hasv4addr = IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)
1275                             ? 1 : 0;
1276                 }
1277                 if (hasv4addr) {
1278                         struct pr_usrreqs *pru;
1279                         uint8_t nxt;
1280
1281                         nxt = (inp->inp_socket->so_proto->pr_protocol ==
1282                             IPPROTO_UDP) ? IPPROTO_UDP : IPPROTO_UDPLITE;
1283                         /*
1284                          * XXXRW: We release UDP-layer locks before calling
1285                          * udp_send() in order to avoid recursion.  However,
1286                          * this does mean there is a short window where inp's
1287                          * fields are unstable.  Could this lead to a
1288                          * potential race in which the factors causing us to
1289                          * select the UDPv4 output routine are invalidated?
1290                          */
1291                         INP_WUNLOCK(inp);
1292                         if (sin6)
1293                                 in6_sin6_2_sin_in_sock(addr);
1294                         pru = inetsw[ip_protox[nxt]].pr_usrreqs;
1295                         /* addr will just be freed in sendit(). */
1296                         return ((*pru->pru_send)(so, flags, m, addr, control,
1297                             td));
1298                 }
1299         }
1300 #endif
1301 #ifdef MAC
1302         mac_inpcb_create_mbuf(inp, m);
1303 #endif
1304         INP_HASH_WLOCK(pcbinfo);
1305         error = udp6_output(inp, m, addr, control, td);
1306         INP_HASH_WUNLOCK(pcbinfo);
1307         INP_WUNLOCK(inp);
1308         return (error);
1309
1310 bad:
1311         INP_WUNLOCK(inp);
1312         m_freem(m);
1313         return (error);
1314 }
1315
1316 struct pr_usrreqs udp6_usrreqs = {
1317         .pru_abort =            udp6_abort,
1318         .pru_attach =           udp6_attach,
1319         .pru_bind =             udp6_bind,
1320         .pru_connect =          udp6_connect,
1321         .pru_control =          in6_control,
1322         .pru_detach =           udp6_detach,
1323         .pru_disconnect =       udp6_disconnect,
1324         .pru_peeraddr =         in6_mapped_peeraddr,
1325         .pru_send =             udp6_send,
1326         .pru_shutdown =         udp_shutdown,
1327         .pru_sockaddr =         in6_mapped_sockaddr,
1328         .pru_soreceive =        soreceive_dgram,
1329         .pru_sosend =           sosend_dgram,
1330         .pru_sosetlabel =       in_pcbsosetlabel,
1331         .pru_close =            udp6_close
1332 };