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