sys/netinet6/udp6_usrreq.c

   1 /*-
   2  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the project nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  *      $KAME: udp6_usrreq.c,v 1.27 2001/05/21 05:45:10 jinmei Exp $
  30  *      $KAME: udp6_output.c,v 1.31 2001/05/21 16:39:15 jinmei Exp $
  31  */
  32
  33 /*-
  34  * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
  35  *      The Regents of the University of California.
  36  * All rights reserved.
  37  *
  38  * Redistribution and use in source and binary forms, with or without
  39  * modification, are permitted provided that the following conditions
  40  * are met:
  41  * 1. Redistributions of source code must retain the above copyright
  42  *    notice, this list of conditions and the following disclaimer.
  43  * 2. Redistributions in binary form must reproduce the above copyright
  44  *    notice, this list of conditions and the following disclaimer in the
  45  *    documentation and/or other materials provided with the distribution.
  46  * 4. Neither the name of the University nor the names of its contributors
  47  *    may be used to endorse or promote products derived from this software
  48  *    without specific prior written permission.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  51  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  52  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  53  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  54  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  55  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  56  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  57  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  58  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  59  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  60  * SUCH DAMAGE.
  61  *
  62  *      @(#)udp_usrreq.c        8.6 (Berkeley) 5/23/95
  63  */
  64
  65 #include <sys/cdefs.h>
  66 __FBSDID("$FreeBSD$");
  67
  68 #include "opt_inet.h"
  69 #include "opt_inet6.h"
  70 #include "opt_ipsec.h"
  71 #include "opt_mac.h"
  72
  73 #include <sys/param.h>
  74 #include <sys/kernel.h>
  75 #include <sys/lock.h>
  76 #include <sys/mbuf.h>
  77 #include <sys/priv.h>
  78 #include <sys/proc.h>
  79 #include <sys/protosw.h>
  80 #include <sys/signalvar.h>
  81 #include <sys/socket.h>
  82 #include <sys/socketvar.h>
  83 #include <sys/sx.h>
  84 #include <sys/sysctl.h>
  85 #include <sys/syslog.h>
  86 #include <sys/systm.h>
  87
  88 #include <net/if.h>
  89 #include <net/if_types.h>
  90 #include <net/route.h>
  91
  92 #include <netinet/in.h>
  93 #include <netinet/in_pcb.h>
  94 #include <netinet/in_systm.h>
  95 #include <netinet/in_var.h>
  96 #include <netinet/ip.h>
  97 #include <netinet/ip_icmp.h>
  98 #include <netinet/ip6.h>
  99 #include <netinet/icmp_var.h>
 100 #include <netinet/icmp6.h>
 101 #include <netinet/ip_var.h>
 102 #include <netinet/udp.h>
 103 #include <netinet/udp_var.h>
 104 #include <netinet6/ip6protosw.h>
 105 #include <netinet6/ip6_var.h>
 106 #include <netinet6/in6_pcb.h>
 107 #include <netinet6/udp6_var.h>
 108 #include <netinet6/scope6_var.h>
 109
 110 #ifdef IPSEC
 111 #include <netipsec/ipsec.h>
 112 #include <netipsec/ipsec6.h>
 113 #endif /* IPSEC */
 114
 115 #include <security/mac/mac_framework.h>
 116
 117 /*
 118  * UDP protocol implementation.
 119  * Per RFC 768, August, 1980.
 120  */
 121
 122 extern struct protosw   inetsw[];
 123 static void             udp6_detach(struct socket *so);
 124
 125 static void
 126 udp6_append(struct inpcb *inp, struct mbuf *n, int off,
 127     struct sockaddr_in6 *fromsa)
 128 {
 129         struct socket *so;
 130         struct mbuf *opts;
 131
 132         INP_LOCK_ASSERT(inp);
 133
 134 #ifdef IPSEC
 135         /* Check AH/ESP integrity. */
 136         if (ipsec6_in_reject(n, inp)) {
 137                 m_freem(n);
 138                 ipsec6stat.in_polvio++;
 139                 return;
 140         }
 141 #endif /* IPSEC */
 142 #ifdef MAC
 143         if (mac_inpcb_check_deliver(inp, n) != 0) {
 144                 m_freem(n);
 145                 return;
 146         }
 147 #endif
 148         opts = NULL;
 149         if (inp->in6p_flags & IN6P_CONTROLOPTS ||
 150             inp->inp_socket->so_options & SO_TIMESTAMP)
 151                 ip6_savecontrol(inp, n, &opts);
 152         m_adj(n, off + sizeof(struct udphdr));
 153
 154         so = inp->inp_socket;
 155         SOCKBUF_LOCK(&so->so_rcv);
 156         if (sbappendaddr_locked(&so->so_rcv, (struct sockaddr *)fromsa, n,
 157             opts) == 0) {
 158                 SOCKBUF_UNLOCK(&so->so_rcv);
 159                 m_freem(n);
 160                 if (opts)
 161                         m_freem(opts);
 162                 udpstat.udps_fullsock++;
 163         } else
 164                 sorwakeup_locked(so);
 165 }
 166
 167 int
 168 udp6_input(struct mbuf **mp, int *offp, int proto)
 169 {
 170         struct mbuf *m = *mp;
 171         struct ip6_hdr *ip6;
 172         struct udphdr *uh;
 173         struct inpcb *inp;
 174         int off = *offp;
 175         int plen, ulen;
 176         struct sockaddr_in6 fromsa;
 177
 178         ip6 = mtod(m, struct ip6_hdr *);
 179
 180         if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) {
 181                 /* XXX send icmp6 host/port unreach? */
 182                 m_freem(m);
 183                 return (IPPROTO_DONE);
 184         }
 185
 186 #ifndef PULLDOWN_TEST
 187         IP6_EXTHDR_CHECK(m, off, sizeof(struct udphdr), IPPROTO_DONE);
 188         ip6 = mtod(m, struct ip6_hdr *);
 189         uh = (struct udphdr *)((caddr_t)ip6 + off);
 190 #else
 191         IP6_EXTHDR_GET(uh, struct udphdr *, m, off, sizeof(*uh));
 192         if (!uh)
 193                 return (IPPROTO_DONE);
 194 #endif
 195
 196         udpstat.udps_ipackets++;
 197
 198         /*
 199          * Destination port of 0 is illegal, based on RFC768.
 200          */
 201         if (uh->uh_dport == 0)
 202                 goto badunlocked;
 203
 204         plen = ntohs(ip6->ip6_plen) - off + sizeof(*ip6);
 205         ulen = ntohs((u_short)uh->uh_ulen);
 206
 207         if (plen != ulen) {
 208                 udpstat.udps_badlen++;
 209                 goto badunlocked;
 210         }
 211
 212         /*
 213          * Checksum extended UDP header and data.
 214          */
 215         if (uh->uh_sum == 0) {
 216                 udpstat.udps_nosum++;
 217                 goto badunlocked;
 218         }
 219         if (in6_cksum(m, IPPROTO_UDP, off, ulen) != 0) {
 220                 udpstat.udps_badsum++;
 221                 goto badunlocked;
 222         }
 223
 224         /*
 225          * Construct sockaddr format source address.
 226          */
 227         init_sin6(&fromsa, m);
 228         fromsa.sin6_port = uh->uh_sport;
 229
 230         INP_INFO_RLOCK(&udbinfo);
 231         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 232                 struct inpcb *last;
 233
 234                 /*
 235                  * In the event that laddr should be set to the link-local
 236                  * address (this happens in RIPng), the multicast address
 237                  * specified in the received packet will not match laddr.  To
 238                  * handle this situation, matching is relaxed if the
 239                  * receiving interface is the same as one specified in the
 240                  * socket and if the destination multicast address matches
 241                  * one of the multicast groups specified in the socket.
 242                  */
 243
 244                 /*
 245                  * KAME note: traditionally we dropped udpiphdr from mbuf
 246                  * here.  We need udphdr for IPsec processing so we do that
 247                  * later.
 248                  */
 249                 last = NULL;
 250                 LIST_FOREACH(inp, &udb, inp_list) {
 251                         if ((inp->inp_vflag & INP_IPV6) == 0)
 252                                 continue;
 253                         if (inp->in6p_lport != uh->uh_dport)
 254                                 continue;
 255                         /*
 256                          * XXX: Do not check source port of incoming datagram
 257                          * unless inp_connect() has been called to bind the
 258                          * fport part of the 4-tuple; the source could be
 259                          * trying to talk to us with an ephemeral port.
 260                          */
 261                         if (inp->inp_fport != 0 &&
 262                             inp->inp_fport != uh->uh_sport)
 263                                 continue;
 264                         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
 265                                 if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr,
 266                                                         &ip6->ip6_dst))
 267                                         continue;
 268                         }
 269                         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 270                                 if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr,
 271                                                         &ip6->ip6_src) ||
 272                                     inp->in6p_fport != uh->uh_sport)
 273                                         continue;
 274                         }
 275
 276                         if (last != NULL) {
 277                                 struct mbuf *n;
 278
 279                                 if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
 280                                         INP_LOCK(last);
 281                                         udp6_append(last, n, off, &fromsa);
 282                                         INP_UNLOCK(last);
 283                                 }
 284                         }
 285                         last = inp;
 286                         /*
 287                          * Don't look for additional matches if this one does
 288                          * not have either the SO_REUSEPORT or SO_REUSEADDR
 289                          * socket options set.  This heuristic avoids
 290                          * searching through all pcbs in the common case of a
 291                          * non-shared port.  It assumes that an application
 292                          * will never clear these options after setting them.
 293                          */
 294                         if ((last->inp_socket->so_options &
 295                              (SO_REUSEPORT|SO_REUSEADDR)) == 0)
 296                                 break;
 297                 }
 298
 299                 if (last == NULL) {
 300                         /*
 301                          * No matching pcb found; discard datagram.  (No need
 302                          * to send an ICMP Port Unreachable for a broadcast
 303                          * or multicast datgram.)
 304                          */
 305                         udpstat.udps_noport++;
 306                         udpstat.udps_noportmcast++;
 307                         goto badheadlocked;
 308                 }
 309                 INP_LOCK(last);
 310                 udp6_append(last, m, off, &fromsa);
 311                 INP_UNLOCK(last);
 312                 INP_INFO_RUNLOCK(&udbinfo);
 313                 return (IPPROTO_DONE);
 314         }
 315         /*
 316          * Locate pcb for datagram.
 317          */
 318         inp = in6_pcblookup_hash(&udbinfo, &ip6->ip6_src, uh->uh_sport,
 319             &ip6->ip6_dst, uh->uh_dport, 1, m->m_pkthdr.rcvif);
 320         if (inp == NULL) {
 321                 if (udp_log_in_vain) {
 322                         char ip6bufs[INET6_ADDRSTRLEN];
 323                         char ip6bufd[INET6_ADDRSTRLEN];
 324
 325                         log(LOG_INFO,
 326                             "Connection attempt to UDP [%s]:%d from [%s]:%d\n",
 327                             ip6_sprintf(ip6bufd, &ip6->ip6_dst),
 328                             ntohs(uh->uh_dport),
 329                             ip6_sprintf(ip6bufs, &ip6->ip6_src),
 330                             ntohs(uh->uh_sport));
 331                 }
 332                 udpstat.udps_noport++;
 333                 if (m->m_flags & M_MCAST) {
 334                         printf("UDP6: M_MCAST is set in a unicast packet.\n");
 335                         udpstat.udps_noportmcast++;
 336                         goto badheadlocked;
 337                 }
 338                 INP_INFO_RUNLOCK(&udbinfo);
 339                 if (udp_blackhole)
 340                         goto badunlocked;
 341                 if (badport_bandlim(BANDLIM_ICMP6_UNREACH) < 0)
 342                         goto badunlocked;
 343                 icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
 344                 return (IPPROTO_DONE);
 345         }
 346         INP_LOCK(inp);
 347         udp6_append(inp, m, off, &fromsa);
 348         INP_UNLOCK(inp);
 349         INP_INFO_RUNLOCK(&udbinfo);
 350         return (IPPROTO_DONE);
 351
 352 badheadlocked:
 353         INP_INFO_RUNLOCK(&udbinfo);
 354 badunlocked:
 355         if (m)
 356                 m_freem(m);
 357         return (IPPROTO_DONE);
 358 }
 359
 360 void
 361 udp6_ctlinput(int cmd, struct sockaddr *sa, void *d)
 362 {
 363         struct udphdr uh;
 364         struct ip6_hdr *ip6;
 365         struct mbuf *m;
 366         int off = 0;
 367         struct ip6ctlparam *ip6cp = NULL;
 368         const struct sockaddr_in6 *sa6_src = NULL;
 369         void *cmdarg;
 370         struct inpcb *(*notify)(struct inpcb *, int) = udp_notify;
 371         struct udp_portonly {
 372                 u_int16_t uh_sport;
 373                 u_int16_t uh_dport;
 374         } *uhp;
 375
 376         if (sa->sa_family != AF_INET6 ||
 377             sa->sa_len != sizeof(struct sockaddr_in6))
 378                 return;
 379
 380         if ((unsigned)cmd >= PRC_NCMDS)
 381                 return;
 382         if (PRC_IS_REDIRECT(cmd))
 383                 notify = in6_rtchange, d = NULL;
 384         else if (cmd == PRC_HOSTDEAD)
 385                 d = NULL;
 386         else if (inet6ctlerrmap[cmd] == 0)
 387                 return;
 388
 389         /* if the parameter is from icmp6, decode it. */
 390         if (d != NULL) {
 391                 ip6cp = (struct ip6ctlparam *)d;
 392                 m = ip6cp->ip6c_m;
 393                 ip6 = ip6cp->ip6c_ip6;
 394                 off = ip6cp->ip6c_off;
 395                 cmdarg = ip6cp->ip6c_cmdarg;
 396                 sa6_src = ip6cp->ip6c_src;
 397         } else {
 398                 m = NULL;
 399                 ip6 = NULL;
 400                 cmdarg = NULL;
 401                 sa6_src = &sa6_any;
 402         }
 403
 404         if (ip6) {
 405                 /*
 406                  * XXX: We assume that when IPV6 is non NULL,
 407                  * M and OFF are valid.
 408                  */
 409
 410                 /* Check if we can safely examine src and dst ports. */
 411                 if (m->m_pkthdr.len < off + sizeof(*uhp))
 412                         return;
 413
 414                 bzero(&uh, sizeof(uh));
 415                 m_copydata(m, off, sizeof(*uhp), (caddr_t)&uh);
 416
 417                 (void) in6_pcbnotify(&udbinfo, sa, uh.uh_dport,
 418                     (struct sockaddr *)ip6cp->ip6c_src, uh.uh_sport, cmd,
 419                     cmdarg, notify);
 420         } else
 421                 (void) in6_pcbnotify(&udbinfo, sa, 0,
 422                     (const struct sockaddr *)sa6_src, 0, cmd, cmdarg, notify);
 423 }
 424
 425 static int
 426 udp6_getcred(SYSCTL_HANDLER_ARGS)
 427 {
 428         struct xucred xuc;
 429         struct sockaddr_in6 addrs[2];
 430         struct inpcb *inp;
 431         int error;
 432
 433         error = priv_check(req->td, PRIV_NETINET_GETCRED);
 434         if (error)
 435                 return (error);
 436
 437         if (req->newlen != sizeof(addrs))
 438                 return (EINVAL);
 439         if (req->oldlen != sizeof(struct xucred))
 440                 return (EINVAL);
 441         error = SYSCTL_IN(req, addrs, sizeof(addrs));
 442         if (error)
 443                 return (error);
 444         if ((error = sa6_embedscope(&addrs[0], ip6_use_defzone)) != 0 ||
 445             (error = sa6_embedscope(&addrs[1], ip6_use_defzone)) != 0) {
 446                 return (error);
 447         }
 448         INP_INFO_RLOCK(&udbinfo);
 449         inp = in6_pcblookup_hash(&udbinfo, &addrs[1].sin6_addr,
 450             addrs[1].sin6_port, &addrs[0].sin6_addr, addrs[0].sin6_port, 1,
 451             NULL);
 452         if (inp == NULL) {
 453                 INP_INFO_RUNLOCK(&udbinfo);
 454                 return (ENOENT);
 455         }
 456         INP_LOCK(inp);
 457         if (inp->inp_socket == NULL) {
 458                 error = ENOENT;
 459                 goto out;
 460         }
 461         error = cr_canseesocket(req->td->td_ucred, inp->inp_socket);
 462         if (error)
 463                 goto out;
 464         cru2x(inp->inp_socket->so_cred, &xuc);
 465 out:
 466         INP_UNLOCK(inp);
 467         INP_INFO_RUNLOCK(&udbinfo);
 468         if (error == 0)
 469                 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
 470         return (error);
 471 }
 472
 473 SYSCTL_PROC(_net_inet6_udp6, OID_AUTO, getcred, CTLTYPE_OPAQUE|CTLFLAG_RW, 0,
 474     0, udp6_getcred, "S,xucred", "Get the xucred of a UDP6 connection");
 475
 476 static int
 477 udp6_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr6,
 478     struct mbuf *control, struct thread *td)
 479 {
 480         u_int32_t ulen = m->m_pkthdr.len;
 481         u_int32_t plen = sizeof(struct udphdr) + ulen;
 482         struct ip6_hdr *ip6;
 483         struct udphdr *udp6;
 484         struct in6_addr *laddr, *faddr;
 485         struct sockaddr_in6 *sin6 = NULL;
 486         struct ifnet *oifp = NULL;
 487         int scope_ambiguous = 0;
 488         u_short fport;
 489         int error = 0;
 490         struct ip6_pktopts *optp, opt;
 491         int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
 492         int flags;
 493         struct sockaddr_in6 tmp;
 494
 495         INP_LOCK_ASSERT(inp);
 496
 497         if (addr6) {
 498                 /* addr6 has been validated in udp6_send(). */
 499                 sin6 = (struct sockaddr_in6 *)addr6;
 500
 501                 /* protect *sin6 from overwrites */
 502                 tmp = *sin6;
 503                 sin6 = &tmp;
 504
 505                 /*
 506                  * Application should provide a proper zone ID or the use of
 507                  * default zone IDs should be enabled.  Unfortunately, some
 508                  * applications do not behave as it should, so we need a
 509                  * workaround.  Even if an appropriate ID is not determined,
 510                  * we'll see if we can determine the outgoing interface.  If we
 511                  * can, determine the zone ID based on the interface below.
 512                  */
 513                 if (sin6->sin6_scope_id == 0 && !ip6_use_defzone)
 514                         scope_ambiguous = 1;
 515                 if ((error = sa6_embedscope(sin6, ip6_use_defzone)) != 0)
 516                         return (error);
 517         }
 518
 519         if (control) {
 520                 if ((error = ip6_setpktopts(control, &opt,
 521                     inp->in6p_outputopts, td->td_ucred, IPPROTO_UDP)) != 0)
 522                         goto release;
 523                 optp = &opt;
 524         } else
 525                 optp = inp->in6p_outputopts;
 526
 527         if (sin6) {
 528                 faddr = &sin6->sin6_addr;
 529
 530                 /*
 531                  * IPv4 version of udp_output calls in_pcbconnect in this case,
 532                  * which needs splnet and affects performance.
 533                  * Since we saw no essential reason for calling in_pcbconnect,
 534                  * we get rid of such kind of logic, and call in6_selectsrc
 535                  * and in6_pcbsetport in order to fill in the local address
 536                  * and the local port.
 537                  */
 538                 if (sin6->sin6_port == 0) {
 539                         error = EADDRNOTAVAIL;
 540                         goto release;
 541                 }
 542
 543                 if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 544                         /* how about ::ffff:0.0.0.0 case? */
 545                         error = EISCONN;
 546                         goto release;
 547                 }
 548
 549                 fport = sin6->sin6_port; /* allow 0 port */
 550
 551                 if (IN6_IS_ADDR_V4MAPPED(faddr)) {
 552                         if ((inp->in6p_flags & IN6P_IPV6_V6ONLY)) {
 553                                 /*
 554                                  * I believe we should explicitly discard the
 555                                  * packet when mapped addresses are disabled,
 556                                  * rather than send the packet as an IPv6 one.
 557                                  * If we chose the latter approach, the packet
 558                                  * might be sent out on the wire based on the
 559                                  * default route, the situation which we'd
 560                                  * probably want to avoid.
 561                                  * (20010421 jinmei@kame.net)
 562                                  */
 563                                 error = EINVAL;
 564                                 goto release;
 565                         }
 566                         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
 567                             !IN6_IS_ADDR_V4MAPPED(&inp->in6p_laddr)) {
 568                                 /*
 569                                  * when remote addr is an IPv4-mapped address,
 570                                  * local addr should not be an IPv6 address,
 571                                  * since you cannot determine how to map IPv6
 572                                  * source address to IPv4.
 573                                  */
 574                                 error = EINVAL;
 575                                 goto release;
 576                         }
 577
 578                         af = AF_INET;
 579                 }
 580
 581                 if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
 582                         laddr = in6_selectsrc(sin6, optp, inp->in6p_moptions,
 583                             NULL, &inp->in6p_laddr, &oifp, &error);
 584                         if (oifp && scope_ambiguous &&
 585                             (error = in6_setscope(&sin6->sin6_addr,
 586                             oifp, NULL))) {
 587                                 goto release;
 588                         }
 589                 } else
 590                         laddr = &inp->in6p_laddr;       /* XXX */
 591                 if (laddr == NULL) {
 592                         if (error == 0)
 593                                 error = EADDRNOTAVAIL;
 594                         goto release;
 595                 }
 596                 if (inp->in6p_lport == 0 &&
 597                     (error = in6_pcbsetport(laddr, inp, td->td_ucred)) != 0)
 598                         goto release;
 599         } else {
 600                 if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 601                         error = ENOTCONN;
 602                         goto release;
 603                 }
 604                 if (IN6_IS_ADDR_V4MAPPED(&inp->in6p_faddr)) {
 605                         if ((inp->in6p_flags & IN6P_IPV6_V6ONLY)) {
 606                                 /*
 607                                  * XXX: this case would happen when the
 608                                  * application sets the V6ONLY flag after
 609                                  * connecting the foreign address.
 610                                  * Such applications should be fixed,
 611                                  * so we bark here.
 612                                  */
 613                                 log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
 614                                     "option was set for a connected socket\n");
 615                                 error = EINVAL;
 616                                 goto release;
 617                         } else
 618                                 af = AF_INET;
 619                 }
 620                 laddr = &inp->in6p_laddr;
 621                 faddr = &inp->in6p_faddr;
 622                 fport = inp->in6p_fport;
 623         }
 624
 625         if (af == AF_INET)
 626                 hlen = sizeof(struct ip);
 627
 628         /*
 629          * Calculate data length and get a mbuf
 630          * for UDP and IP6 headers.
 631          */
 632         M_PREPEND(m, hlen + sizeof(struct udphdr), M_DONTWAIT);
 633         if (m == 0) {
 634                 error = ENOBUFS;
 635                 goto release;
 636         }
 637
 638         /*
 639          * Stuff checksum and output datagram.
 640          */
 641         udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
 642         udp6->uh_sport = inp->in6p_lport; /* lport is always set in the PCB */
 643         udp6->uh_dport = fport;
 644         if (plen <= 0xffff)
 645                 udp6->uh_ulen = htons((u_short)plen);
 646         else
 647                 udp6->uh_ulen = 0;
 648         udp6->uh_sum = 0;
 649
 650         switch (af) {
 651         case AF_INET6:
 652                 ip6 = mtod(m, struct ip6_hdr *);
 653                 ip6->ip6_flow   = inp->in6p_flowinfo & IPV6_FLOWINFO_MASK;
 654                 ip6->ip6_vfc    &= ~IPV6_VERSION_MASK;
 655                 ip6->ip6_vfc    |= IPV6_VERSION;
 656 #if 0                           /* ip6_plen will be filled in ip6_output. */
 657                 ip6->ip6_plen   = htons((u_short)plen);
 658 #endif
 659                 ip6->ip6_nxt    = IPPROTO_UDP;
 660                 ip6->ip6_hlim   = in6_selecthlim(inp, NULL);
 661                 ip6->ip6_src    = *laddr;
 662                 ip6->ip6_dst    = *faddr;
 663
 664                 if ((udp6->uh_sum = in6_cksum(m, IPPROTO_UDP,
 665                                 sizeof(struct ip6_hdr), plen)) == 0) {
 666                         udp6->uh_sum = 0xffff;
 667                 }
 668
 669                 flags = 0;
 670
 671                 udpstat.udps_opackets++;
 672                 error = ip6_output(m, optp, NULL, flags, inp->in6p_moptions,
 673                     NULL, inp);
 674                 break;
 675         case AF_INET:
 676                 error = EAFNOSUPPORT;
 677                 goto release;
 678         }
 679         goto releaseopt;
 680
 681 release:
 682         m_freem(m);
 683
 684 releaseopt:
 685         if (control) {
 686                 ip6_clearpktopts(&opt, -1);
 687                 m_freem(control);
 688         }
 689         return (error);
 690 }
 691
 692 static void
 693 udp6_abort(struct socket *so)
 694 {
 695         struct inpcb *inp;
 696
 697         inp = sotoinpcb(so);
 698         KASSERT(inp != NULL, ("udp6_abort: inp == NULL"));
 699
 700 #ifdef INET
 701         if (inp->inp_vflag & INP_IPV4) {
 702                 struct pr_usrreqs *pru;
 703
 704                 pru = inetsw[ip_protox[IPPROTO_UDP]].pr_usrreqs;
 705                 (*pru->pru_abort)(so);
 706                 return;
 707         }
 708 #endif
 709
 710         INP_INFO_WLOCK(&udbinfo);
 711         INP_LOCK(inp);
 712         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 713                 in6_pcbdisconnect(inp);
 714                 inp->in6p_laddr = in6addr_any;
 715                 soisdisconnected(so);
 716         }
 717         INP_UNLOCK(inp);
 718         INP_INFO_WUNLOCK(&udbinfo);
 719 }
 720
 721 static int
 722 udp6_attach(struct socket *so, int proto, struct thread *td)
 723 {
 724         struct inpcb *inp;
 725         int error;
 726
 727         inp = sotoinpcb(so);
 728         KASSERT(inp == NULL, ("udp6_attach: inp != NULL"));
 729
 730         if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
 731                 error = soreserve(so, udp_sendspace, udp_recvspace);
 732                 if (error)
 733                         return (error);
 734         }
 735         INP_INFO_WLOCK(&udbinfo);
 736         error = in_pcballoc(so, &udbinfo);
 737         if (error) {
 738                 INP_INFO_WUNLOCK(&udbinfo);
 739                 return (error);
 740         }
 741         inp = (struct inpcb *)so->so_pcb;
 742         INP_INFO_WUNLOCK(&udbinfo);
 743         inp->inp_vflag |= INP_IPV6;
 744         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
 745                 inp->inp_vflag |= INP_IPV4;
 746         inp->in6p_hops = -1;    /* use kernel default */
 747         inp->in6p_cksum = -1;   /* just to be sure */
 748         /*
 749          * XXX: ugly!!
 750          * IPv4 TTL initialization is necessary for an IPv6 socket as well,
 751          * because the socket may be bound to an IPv6 wildcard address,
 752          * which may match an IPv4-mapped IPv6 address.
 753          */
 754         inp->inp_ip_ttl = ip_defttl;
 755         INP_UNLOCK(inp);
 756         return (0);
 757 }
 758
 759 static int
 760 udp6_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
 761 {
 762         struct inpcb *inp;
 763         int error;
 764
 765         inp = sotoinpcb(so);
 766         KASSERT(inp != NULL, ("udp6_bind: inp == NULL"));
 767
 768         INP_INFO_WLOCK(&udbinfo);
 769         INP_LOCK(inp);
 770         inp->inp_vflag &= ~INP_IPV4;
 771         inp->inp_vflag |= INP_IPV6;
 772         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
 773                 struct sockaddr_in6 *sin6_p;
 774
 775                 sin6_p = (struct sockaddr_in6 *)nam;
 776
 777                 if (IN6_IS_ADDR_UNSPECIFIED(&sin6_p->sin6_addr))
 778                         inp->inp_vflag |= INP_IPV4;
 779                 else if (IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {
 780                         struct sockaddr_in sin;
 781
 782                         in6_sin6_2_sin(&sin, sin6_p);
 783                         inp->inp_vflag |= INP_IPV4;
 784                         inp->inp_vflag &= ~INP_IPV6;
 785                         error = in_pcbbind(inp, (struct sockaddr *)&sin,
 786                             td->td_ucred);
 787                         goto out;
 788                 }
 789         }
 790
 791         error = in6_pcbbind(inp, nam, td->td_ucred);
 792 out:
 793         INP_UNLOCK(inp);
 794         INP_INFO_WUNLOCK(&udbinfo);
 795         return (error);
 796 }
 797
 798 static void
 799 udp6_close(struct socket *so)
 800 {
 801         struct inpcb *inp;
 802
 803         inp = sotoinpcb(so);
 804         KASSERT(inp != NULL, ("udp6_close: inp == NULL"));
 805
 806 #ifdef INET
 807         if (inp->inp_vflag & INP_IPV4) {
 808                 struct pr_usrreqs *pru;
 809
 810                 pru = inetsw[ip_protox[IPPROTO_UDP]].pr_usrreqs;
 811                 (*pru->pru_disconnect)(so);
 812                 return;
 813         }
 814 #endif
 815         INP_INFO_WLOCK(&udbinfo);
 816         INP_LOCK(inp);
 817         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 818                 in6_pcbdisconnect(inp);
 819                 inp->in6p_laddr = in6addr_any;
 820                 soisdisconnected(so);
 821         }
 822         INP_UNLOCK(inp);
 823         INP_INFO_WUNLOCK(&udbinfo);
 824 }
 825
 826 static int
 827 udp6_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
 828 {
 829         struct inpcb *inp;
 830         int error;
 831
 832         inp = sotoinpcb(so);
 833         KASSERT(inp != NULL, ("udp6_connect: inp == NULL"));
 834
 835         INP_INFO_WLOCK(&udbinfo);
 836         INP_LOCK(inp);
 837         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
 838                 struct sockaddr_in6 *sin6_p;
 839
 840                 sin6_p = (struct sockaddr_in6 *)nam;
 841                 if (IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {
 842                         struct sockaddr_in sin;
 843
 844                         if (inp->inp_faddr.s_addr != INADDR_ANY) {
 845                                 error = EISCONN;
 846                                 goto out;
 847                         }
 848                         in6_sin6_2_sin(&sin, sin6_p);
 849                         error = in_pcbconnect(inp, (struct sockaddr *)&sin,
 850                             td->td_ucred);
 851                         if (error == 0) {
 852                                 inp->inp_vflag |= INP_IPV4;
 853                                 inp->inp_vflag &= ~INP_IPV6;
 854                                 soisconnected(so);
 855                         }
 856                         goto out;
 857                 }
 858         }
 859         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 860                 error = EISCONN;
 861                 goto out;
 862         }
 863         error = in6_pcbconnect(inp, nam, td->td_ucred);
 864         if (error == 0) {
 865                 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
 866                         /* should be non mapped addr */
 867                         inp->inp_vflag &= ~INP_IPV4;
 868                         inp->inp_vflag |= INP_IPV6;
 869                 }
 870                 soisconnected(so);
 871         }
 872 out:
 873         INP_UNLOCK(inp);
 874         INP_INFO_WUNLOCK(&udbinfo);
 875         return (error);
 876 }
 877
 878 static void
 879 udp6_detach(struct socket *so)
 880 {
 881         struct inpcb *inp;
 882
 883         inp = sotoinpcb(so);
 884         KASSERT(inp != NULL, ("udp6_detach: inp == NULL"));
 885
 886         INP_INFO_WLOCK(&udbinfo);
 887         INP_LOCK(inp);
 888         in6_pcbdetach(inp);
 889         in6_pcbfree(inp);
 890         INP_INFO_WUNLOCK(&udbinfo);
 891 }
 892
 893 static int
 894 udp6_disconnect(struct socket *so)
 895 {
 896         struct inpcb *inp;
 897         int error;
 898
 899         inp = sotoinpcb(so);
 900         KASSERT(inp != NULL, ("udp6_disconnect: inp == NULL"));
 901
 902         INP_INFO_WLOCK(&udbinfo);
 903         INP_LOCK(inp);
 904
 905 #ifdef INET
 906         if (inp->inp_vflag & INP_IPV4) {
 907                 struct pr_usrreqs *pru;
 908
 909                 pru = inetsw[ip_protox[IPPROTO_UDP]].pr_usrreqs;
 910                 error = (*pru->pru_disconnect)(so);
 911                 goto out;
 912         }
 913 #endif
 914
 915         if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
 916                 error = ENOTCONN;
 917                 goto out;
 918         }
 919
 920         in6_pcbdisconnect(inp);
 921         inp->in6p_laddr = in6addr_any;
 922         /* XXXRW: so_state locking? */
 923         so->so_state &= ~SS_ISCONNECTED;                /* XXX */
 924 out:
 925         INP_UNLOCK(inp);
 926         INP_INFO_WUNLOCK(&udbinfo);
 927         return (0);
 928 }
 929
 930 static int
 931 udp6_send(struct socket *so, int flags, struct mbuf *m,
 932     struct sockaddr *addr, struct mbuf *control, struct thread *td)
 933 {
 934         struct inpcb *inp;
 935         int error = 0;
 936
 937         inp = sotoinpcb(so);
 938         KASSERT(inp != NULL, ("udp6_send: inp == NULL"));
 939
 940         INP_INFO_WLOCK(&udbinfo);
 941         INP_LOCK(inp);
 942         if (addr) {
 943                 if (addr->sa_len != sizeof(struct sockaddr_in6)) {
 944                         error = EINVAL;
 945                         goto bad;
 946                 }
 947                 if (addr->sa_family != AF_INET6) {
 948                         error = EAFNOSUPPORT;
 949                         goto bad;
 950                 }
 951         }
 952
 953 #ifdef INET
 954         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
 955                 int hasv4addr;
 956                 struct sockaddr_in6 *sin6 = 0;
 957
 958                 if (addr == 0)
 959                         hasv4addr = (inp->inp_vflag & INP_IPV4);
 960                 else {
 961                         sin6 = (struct sockaddr_in6 *)addr;
 962                         hasv4addr = IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)
 963                             ? 1 : 0;
 964                 }
 965                 if (hasv4addr) {
 966                         struct pr_usrreqs *pru;
 967
 968                         if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
 969                             !IN6_IS_ADDR_V4MAPPED(&inp->in6p_laddr)) {
 970                                 /*
 971                                  * When remote addr is IPv4-mapped address,
 972                                  * local addr should not be an IPv6 address;
 973                                  * since you cannot determine how to map IPv6
 974                                  * source address to IPv4.
 975                                  */
 976                                 error = EINVAL;
 977                                 goto out;
 978                         }
 979                         if (sin6)
 980                                 in6_sin6_2_sin_in_sock(addr);
 981                         pru = inetsw[ip_protox[IPPROTO_UDP]].pr_usrreqs;
 982                         error = ((*pru->pru_send)(so, flags, m, addr, control,
 983                             td));
 984                         /* addr will just be freed in sendit(). */
 985                         goto out;
 986                 }
 987         }
 988 #endif
 989 #ifdef MAC
 990         mac_inpcb_create_mbuf(inp, m);
 991 #endif
 992         error = udp6_output(inp, m, addr, control, td);
 993 out:
 994         INP_UNLOCK(inp);
 995         INP_INFO_WUNLOCK(&udbinfo);
 996         return (error);
 997
 998 bad:
 999         INP_UNLOCK(inp);
1000         INP_INFO_WUNLOCK(&udbinfo);
1001         m_freem(m);
1002         return (error);
1003 }
1004
1005 struct pr_usrreqs udp6_usrreqs = {
1006         .pru_abort =            udp6_abort,
1007         .pru_attach =           udp6_attach,
1008         .pru_bind =             udp6_bind,
1009         .pru_connect =          udp6_connect,
1010         .pru_control =          in6_control,
1011         .pru_detach =           udp6_detach,
1012         .pru_disconnect =       udp6_disconnect,
1013         .pru_peeraddr =         in6_mapped_peeraddr,
1014         .pru_send =             udp6_send,
1015         .pru_shutdown =         udp_shutdown,
1016         .pru_sockaddr =         in6_mapped_sockaddr,
1017         .pru_sosetlabel =       in_pcbsosetlabel,
1018         .pru_close =            udp6_close
1019 };