bsd/netinet6/udp6_output.c

   1 /*
   2  * Copyright (c) 2000-2012 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29
  30 /*      $FreeBSD: src/sys/netinet6/udp6_output.c,v 1.1.2.3 2001/08/31 13:49:58 jlemon Exp $     */
  31 /*      $KAME: udp6_output.c,v 1.31 2001/05/21 16:39:15 jinmei Exp $    */
  32
  33 /*
  34  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
  35  * All rights reserved.
  36  *
  37  * Redistribution and use in source and binary forms, with or without
  38  * modification, are permitted provided that the following conditions
  39  * are met:
  40  * 1. Redistributions of source code must retain the above copyright
  41  *    notice, this list of conditions and the following disclaimer.
  42  * 2. Redistributions in binary form must reproduce the above copyright
  43  *    notice, this list of conditions and the following disclaimer in the
  44  *    documentation and/or other materials provided with the distribution.
  45  * 3. Neither the name of the project nor the names of its contributors
  46  *    may be used to endorse or promote products derived from this software
  47  *    without specific prior written permission.
  48  *
  49  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  59  * SUCH DAMAGE.
  60  */
  61
  62 /*
  63  * Copyright (c) 1982, 1986, 1989, 1993
  64  *      The Regents of the University of California.  All rights reserved.
  65  *
  66  * Redistribution and use in source and binary forms, with or without
  67  * modification, are permitted provided that the following conditions
  68  * are met:
  69  * 1. Redistributions of source code must retain the above copyright
  70  *    notice, this list of conditions and the following disclaimer.
  71  * 2. Redistributions in binary form must reproduce the above copyright
  72  *    notice, this list of conditions and the following disclaimer in the
  73  *    documentation and/or other materials provided with the distribution.
  74  * 3. All advertising materials mentioning features or use of this software
  75  *    must display the following acknowledgement:
  76  *      This product includes software developed by the University of
  77  *      California, Berkeley and its contributors.
  78  * 4. Neither the name of the University nor the names of its contributors
  79  *    may be used to endorse or promote products derived from this software
  80  *    without specific prior written permission.
  81  *
  82  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  83  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  84  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  85  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  86  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  87  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  88  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  89  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  90  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  91  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  92  * SUCH DAMAGE.
  93  *
  94  *      @(#)udp_var.h   8.1 (Berkeley) 6/10/93
  95  */
  96
  97 #include <sys/param.h>
  98 #include <sys/malloc.h>
  99 #include <sys/mbuf.h>
 100 #include <sys/protosw.h>
 101 #include <sys/socket.h>
 102 #include <sys/socketvar.h>
 103 #include <sys/sysctl.h>
 104 #include <sys/errno.h>
 105 #include <sys/stat.h>
 106 #include <sys/systm.h>
 107 #include <sys/proc.h>
 108 #include <sys/syslog.h>
 109
 110 #include <machine/endian.h>
 111
 112 #include <net/if.h>
 113 #include <net/route.h>
 114 #include <net/if_types.h>
 115 #include <net/ntstat.h>
 116
 117 #include <netinet/in.h>
 118 #include <netinet/in_var.h>
 119 #include <netinet/in_systm.h>
 120 #include <netinet/ip.h>
 121 #include <netinet/ip_var.h>
 122 #include <netinet/in_pcb.h>
 123 #include <netinet/udp.h>
 124 #include <netinet/udp_var.h>
 125 #include <netinet/ip6.h>
 126 #include <netinet6/ip6_var.h>
 127 #include <netinet6/in6_pcb.h>
 128 #include <netinet6/udp6_var.h>
 129 #include <netinet/icmp6.h>
 130 #include <netinet6/ip6protosw.h>
 131
 132 #ifdef IPSEC
 133 #include <netinet6/ipsec.h>
 134 #ifdef INET6
 135 #include <netinet6/ipsec6.h>
 136 #endif
 137 extern int ipsec_bypass;
 138 #endif /*IPSEC*/
 139
 140 #include <net/net_osdep.h>
 141
 142 /*
 143  * UDP protocol inplementation.
 144  * Per RFC 768, August, 1980.
 145  */
 146
 147 #define in6pcb          inpcb
 148 #define udp6stat        udpstat
 149 #define udp6s_opackets  udps_opackets
 150
 151 static __inline__ u_int16_t
 152 get_socket_id(struct socket * s)
 153 {
 154         u_int16_t               val;
 155
 156         if (s == NULL) {
 157             return (0);
 158         }
 159         val = (u_int16_t)(((uintptr_t)s) / sizeof(struct socket));
 160         if (val == 0) {
 161                 val = 0xffff;
 162         }
 163         return (val);
 164 }
 165
 166 int
 167 udp6_output(in6p, m, addr6, control, p)
 168         struct in6pcb *in6p;
 169         struct mbuf *m;
 170         struct mbuf *control;
 171         struct sockaddr *addr6;
 172         struct proc *p;
 173 {
 174         u_int32_t ulen = m->m_pkthdr.len;
 175         u_int32_t plen = sizeof(struct udphdr) + ulen;
 176         struct ip6_hdr *ip6;
 177         struct udphdr *udp6;
 178         struct in6_addr *laddr, *faddr;
 179         u_short fport;
 180         int error = 0;
 181         struct ip6_pktopts opt, *optp = NULL;
 182         struct ip6_moptions *im6o;
 183         int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
 184         int flags;
 185         struct sockaddr_in6 tmp;
 186         struct  in6_addr storage;
 187         mbuf_svc_class_t msc = MBUF_SC_UNSPEC;
 188         struct ip6_out_args ip6oa =
 189             { IFSCOPE_NONE, { 0 }, IP6OAF_SELECT_SRCIF };
 190         struct flowadv *adv = &ip6oa.ip6oa_flowadv;
 191         int flowadv = 0;
 192
 193         /* Enable flow advisory only when connected */
 194         flowadv = (in6p->inp_socket->so_state & SS_ISCONNECTED) ? 1 : 0;
 195
 196         if (flowadv && INP_WAIT_FOR_IF_FEEDBACK(in6p)) {
 197                 error = ENOBUFS;
 198                 goto release;
 199         }
 200
 201         if (in6p->inp_flags & INP_BOUND_IF) {
 202                 ip6oa.ip6oa_boundif = in6p->inp_boundifp->if_index;
 203                 ip6oa.ip6oa_flags |= IP6OAF_BOUND_IF;
 204         }
 205         if (in6p->inp_flags & INP_NO_IFT_CELLULAR)
 206                 ip6oa.ip6oa_flags |= IP6OAF_NO_CELLULAR;
 207
 208         if (control) {
 209                 msc = mbuf_service_class_from_control(control);
 210
 211                 if ((error = ip6_setpktopts(control, &opt, NULL, IPPROTO_UDP)) != 0)
 212                         goto release;
 213                 optp = &opt;
 214         } else
 215                 optp = in6p->in6p_outputopts;
 216
 217         if (addr6) {
 218                 /*
 219                  * IPv4 version of udp_output calls in_pcbconnect in this case,
 220                  * which needs splnet and affects performance.
 221                  * Since we saw no essential reason for calling in_pcbconnect,
 222                  * we get rid of such kind of logic, and call in6_selectsrc
 223                  * and in6_pcbsetport in order to fill in the local address
 224                  * and the local port.
 225                  */
 226                 struct sockaddr_in6 *sin6 =
 227                     (struct sockaddr_in6 *)(void *)addr6;
 228
 229                 if (sin6->sin6_port == 0) {
 230                         error = EADDRNOTAVAIL;
 231                         goto release;
 232                 }
 233
 234                 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
 235                         /* how about ::ffff:0.0.0.0 case? */
 236                         error = EISCONN;
 237                         goto release;
 238                 }
 239
 240                 /* protect *sin6 from overwrites */
 241                 tmp = *sin6;
 242                 sin6 = &tmp;
 243
 244                 faddr = &sin6->sin6_addr;
 245                 fport = sin6->sin6_port; /* allow 0 port */
 246
 247                 if (IN6_IS_ADDR_V4MAPPED(faddr)) {
 248                         if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
 249                                 /*
 250                                  * I believe we should explicitly discard the
 251                                  * packet when mapped addresses are disabled,
 252                                  * rather than send the packet as an IPv6 one.
 253                                  * If we chose the latter approach, the packet
 254                                  * might be sent out on the wire based on the
 255                                  * default route, the situation which we'd
 256                                  * probably want to avoid.
 257                                  * (20010421 jinmei@kame.net)
 258                                  */
 259                                 error = EINVAL;
 260                                 goto release;
 261                         } else
 262                                 af = AF_INET;
 263                 }
 264
 265                 /* KAME hack: embed scopeid */
 266                 if (in6_embedscope(&sin6->sin6_addr, sin6, in6p, NULL,
 267                     optp) != 0) {
 268                         error = EINVAL;
 269                         goto release;
 270                 }
 271
 272                 if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
 273                         laddr = in6_selectsrc(sin6, optp,
 274                             in6p, &in6p->in6p_route, NULL, &storage,
 275                             ip6oa.ip6oa_boundif, &error);
 276                 } else
 277                         laddr = &in6p->in6p_laddr;      /* XXX */
 278                 if (laddr == NULL) {
 279                         if (error == 0)
 280                                 error = EADDRNOTAVAIL;
 281                         goto release;
 282                 }
 283                 if (in6p->in6p_lport == 0 &&
 284                     (error = in6_pcbsetport(laddr, in6p, p, 0)) != 0)
 285                         goto release;
 286         } else {
 287                 if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
 288                         error = ENOTCONN;
 289                         goto release;
 290                 }
 291                 if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) {
 292                         if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
 293                                 /*
 294                                  * XXX: this case would happen when the
 295                                  * application sets the V6ONLY flag after
 296                                  * connecting the foreign address.
 297                                  * Such applications should be fixed,
 298                                  * so we bark here.
 299                                  */
 300                                 log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
 301                                     "option was set for a connected socket\n");
 302                                 error = EINVAL;
 303                                 goto release;
 304                         } else
 305                                 af = AF_INET;
 306                 }
 307                 laddr = &in6p->in6p_laddr;
 308                 faddr = &in6p->in6p_faddr;
 309                 fport = in6p->in6p_fport;
 310         }
 311
 312         if (in6p->inp_flowhash == 0)
 313                 in6p->inp_flowhash = inp_calc_flowhash(in6p);
 314
 315         if (af == AF_INET)
 316                 hlen = sizeof(struct ip);
 317
 318         /*
 319          * Calculate data length and get a mbuf
 320          * for UDP and IP6 headers.
 321          */
 322         M_PREPEND(m, hlen + sizeof(struct udphdr), M_DONTWAIT);
 323         if (m == 0) {
 324                 error = ENOBUFS;
 325                 goto release;
 326         }
 327
 328         /*
 329          * Stuff checksum and output datagram.
 330          */
 331         udp6 = (struct udphdr *)(void *)(mtod(m, caddr_t) + hlen);
 332         udp6->uh_sport = in6p->in6p_lport; /* lport is always set in the PCB */
 333         udp6->uh_dport = fport;
 334         if (plen <= 0xffff)
 335                 udp6->uh_ulen = htons((u_short)plen);
 336         else
 337                 udp6->uh_ulen = 0;
 338         udp6->uh_sum = 0;
 339
 340         switch (af) {
 341         case AF_INET6:
 342                 ip6 = mtod(m, struct ip6_hdr *);
 343                 ip6->ip6_flow   = in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK;
 344                 ip6->ip6_vfc    &= ~IPV6_VERSION_MASK;
 345                 ip6->ip6_vfc    |= IPV6_VERSION;
 346 #if 0                           /* ip6_plen will be filled in ip6_output. */
 347                 ip6->ip6_plen   = htons((u_short)plen);
 348 #endif
 349                 ip6->ip6_nxt    = IPPROTO_UDP;
 350                 ip6->ip6_hlim   = in6_selecthlim(in6p,
 351                                                  in6p->in6p_route.ro_rt ?
 352                                                  in6p->in6p_route.ro_rt->rt_ifp : NULL);
 353                 ip6->ip6_src    = *laddr;
 354                 ip6->ip6_dst    = *faddr;
 355
 356                 udp6->uh_sum = in6_cksum_phdr(laddr, faddr,
 357                     htonl(plen), htonl(IPPROTO_UDP));
 358                 m->m_pkthdr.csum_flags = CSUM_UDPIPV6;
 359                 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
 360
 361                 if (!IN6_IS_ADDR_UNSPECIFIED(laddr))
 362                         ip6oa.ip6oa_flags |= IP6OAF_BOUND_SRCADDR;
 363
 364                 flags = IPV6_OUTARGS;
 365
 366                 udp6stat.udp6s_opackets++;
 367 #ifdef IPSEC
 368                 if (ipsec_bypass == 0 && ipsec_setsocket(m, in6p->in6p_socket) != 0) {
 369                         error = ENOBUFS;
 370                         goto release;
 371                 }
 372 #endif /*IPSEC*/
 373                 m->m_pkthdr.socket_id = get_socket_id(in6p->in6p_socket);
 374
 375                 set_packet_service_class(m, in6p->in6p_socket, msc, PKT_SCF_IPV6);
 376
 377                 m->m_pkthdr.m_flowhash = in6p->inp_flowhash;
 378                 m->m_pkthdr.m_fhflags |= PF_TAG_FLOWHASH;
 379                 if (flowadv)
 380                         m->m_pkthdr.m_fhflags |= PF_TAG_FLOWADV;
 381
 382                 im6o = in6p->in6p_moptions;
 383                 if (im6o != NULL) {
 384                         IM6O_LOCK(im6o);
 385                         IM6O_ADDREF_LOCKED(im6o);
 386                         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
 387                             im6o->im6o_multicast_ifp != NULL) {
 388                                 in6p->in6p_last_outifp = im6o->im6o_multicast_ifp;
 389                         }
 390                         IM6O_UNLOCK(im6o);
 391                 }
 392
 393                 in6p->inp_sndinprog_cnt++;
 394
 395                 error = ip6_output(m, optp, &in6p->in6p_route,
 396                     flags, im6o, NULL, &ip6oa);
 397
 398                 if (im6o != NULL)
 399                         IM6O_REMREF(im6o);
 400
 401                 if (error == 0 && nstat_collect) {
 402                         locked_add_64(&in6p->inp_stat->txpackets, 1);
 403                         locked_add_64(&in6p->inp_stat->txbytes, ulen);
 404                 }
 405
 406                 if (flowadv && (adv->code == FADV_FLOW_CONTROLLED ||
 407                     adv->code == FADV_SUSPENDED)) {
 408                         /* return an error to indicate
 409                          * that the packet has been dropped
 410                          */
 411                         error = ENOBUFS;
 412                         inp_set_fc_state(in6p, adv->code);
 413                 }
 414
 415                 VERIFY(in6p->inp_sndinprog_cnt > 0);
 416                 if ( --in6p->inp_sndinprog_cnt == 0)
 417                         in6p->inp_flags &= ~(INP_FC_FEEDBACK);
 418
 419                 if (in6p->in6p_route.ro_rt != NULL) {
 420                         struct rtentry *rt = in6p->in6p_route.ro_rt;
 421                         struct ifnet *outif;
 422
 423                         if ((rt->rt_flags & RTF_MULTICAST) ||
 424                             in6p->in6p_socket == NULL ||
 425                             !(in6p->in6p_socket->so_state & SS_ISCONNECTED)) {
 426                                 rt = NULL;      /* unusable */
 427                         }
 428                         /*
 429                          * Always discard the cached route for unconnected
 430                          * socket or if it is a multicast route.
 431                          */
 432                         if (rt == NULL) {
 433                                 rtfree(in6p->in6p_route.ro_rt);
 434                                 in6p->in6p_route.ro_rt = NULL;
 435                         }
 436                         /*
 437                          * If this is a connected socket and the destination
 438                          * route is not multicast, update outif with that of
 439                          * the route interface used by IP.
 440                          */
 441                         if (rt != NULL &&
 442                             (outif = rt->rt_ifp) != in6p->in6p_last_outifp)
 443                                 in6p->in6p_last_outifp = outif;
 444                 }
 445                 break;
 446         case AF_INET:
 447                 error = EAFNOSUPPORT;
 448                 goto release;
 449         }
 450         goto releaseopt;
 451
 452 release:
 453         m_freem(m);
 454
 455 releaseopt:
 456         if (control) {
 457                 if (optp == &opt)
 458                         ip6_clearpktopts(optp, -1);
 459                 m_freem(control);
 460         }
 461         return(error);
 462 }