bsd/netinet6/udp6_output.c

   1 /*
   2  * Copyright (c) 2008-2010 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 <net/if.h>
 111 #include <net/route.h>
 112 #include <net/if_types.h>
 113
 114 #include <netinet/in.h>
 115 #include <netinet/in_var.h>
 116 #include <netinet/in_systm.h>
 117 #include <netinet/ip.h>
 118 #include <netinet/ip_var.h>
 119 #include <netinet/in_pcb.h>
 120 #include <netinet/udp.h>
 121 #include <netinet/udp_var.h>
 122 #include <netinet/ip6.h>
 123 #include <netinet6/ip6_var.h>
 124 #include <netinet6/in6_pcb.h>
 125 #include <netinet6/udp6_var.h>
 126 #include <netinet/icmp6.h>
 127 #include <netinet6/ip6protosw.h>
 128
 129 #ifdef IPSEC
 130 #include <netinet6/ipsec.h>
 131 #ifdef INET6
 132 #include <netinet6/ipsec6.h>
 133 #endif
 134 extern int ipsec_bypass;
 135 #endif /*IPSEC*/
 136
 137 #include "faith.h"
 138
 139 #include <net/net_osdep.h>
 140
 141 /*
 142  * UDP protocol inplementation.
 143  * Per RFC 768, August, 1980.
 144  */
 145
 146 #define in6pcb          inpcb
 147 #define udp6stat        udpstat
 148 #define udp6s_opackets  udps_opackets
 149
 150 static __inline__ u_int16_t
 151 get_socket_id(struct socket * s)
 152 {
 153         u_int16_t               val;
 154
 155         if (s == NULL) {
 156             return (0);
 157         }
 158         val = (u_int16_t)(((uintptr_t)s) / sizeof(struct socket));
 159         if (val == 0) {
 160                 val = 0xffff;
 161         }
 162         return (val);
 163 }
 164
 165 int
 166 udp6_output(in6p, m, addr6, control, p)
 167         struct in6pcb *in6p;
 168         struct mbuf *m;
 169         struct mbuf *control;
 170         struct sockaddr *addr6;
 171         struct proc *p;
 172 {
 173         u_int32_t ulen = m->m_pkthdr.len;
 174         u_int32_t plen = sizeof(struct udphdr) + ulen;
 175         struct ip6_hdr *ip6;
 176         struct udphdr *udp6;
 177         struct in6_addr *laddr, *faddr;
 178         u_short fport;
 179         int error = 0;
 180         struct ip6_pktopts opt, *stickyopt = in6p->in6p_outputopts;
 181         int priv;
 182         int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
 183         int flags;
 184         struct sockaddr_in6 tmp;
 185         struct  in6_addr storage;
 186 #if PKT_PRIORITY
 187         mbuf_traffic_class_t mtc = MBUF_TC_NONE;
 188 #endif /* PKT_PRIORITY */
 189
 190         priv = (proc_suser(p) == 0);
 191
 192         if (control) {
 193 #if PKT_PRIORITY
 194                 mtc = mbuf_traffic_class_from_control(control);
 195 #endif /* PKT_PRIORITY */
 196
 197                 if ((error = ip6_setpktoptions(control, &opt, priv, 0)) != 0)
 198                         goto release;
 199                 in6p->in6p_outputopts = &opt;
 200         }
 201
 202         if (addr6) {
 203                 /*
 204                  * IPv4 version of udp_output calls in_pcbconnect in this case,
 205                  * which needs splnet and affects performance.
 206                  * Since we saw no essential reason for calling in_pcbconnect,
 207                  * we get rid of such kind of logic, and call in6_selectsrc
 208                  * and in6_pcbsetport in order to fill in the local address
 209                  * and the local port.
 210                  */
 211                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)addr6;
 212                 if (sin6->sin6_port == 0) {
 213                         error = EADDRNOTAVAIL;
 214                         goto release;
 215                 }
 216
 217                 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
 218                         /* how about ::ffff:0.0.0.0 case? */
 219                         error = EISCONN;
 220                         goto release;
 221                 }
 222
 223                 /* protect *sin6 from overwrites */
 224                 tmp = *sin6;
 225                 sin6 = &tmp;
 226
 227                 faddr = &sin6->sin6_addr;
 228                 fport = sin6->sin6_port; /* allow 0 port */
 229
 230                 if (IN6_IS_ADDR_V4MAPPED(faddr)) {
 231                         if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
 232                                 /*
 233                                  * I believe we should explicitly discard the
 234                                  * packet when mapped addresses are disabled,
 235                                  * rather than send the packet as an IPv6 one.
 236                                  * If we chose the latter approach, the packet
 237                                  * might be sent out on the wire based on the
 238                                  * default route, the situation which we'd
 239                                  * probably want to avoid.
 240                                  * (20010421 jinmei@kame.net)
 241                                  */
 242                                 error = EINVAL;
 243                                 goto release;
 244                         } else
 245                                 af = AF_INET;
 246                 }
 247
 248                 /* KAME hack: embed scopeid */
 249                 if (in6_embedscope(&sin6->sin6_addr, sin6, in6p, NULL) != 0) {
 250                         error = EINVAL;
 251                         goto release;
 252                 }
 253
 254                 if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
 255                         laddr = in6_selectsrc(sin6, in6p->in6p_outputopts,
 256                                               in6p->in6p_moptions,
 257                                               &in6p->in6p_route,
 258                                               &in6p->in6p_laddr, &storage, &error);
 259                 } else
 260                         laddr = &in6p->in6p_laddr;      /* XXX */
 261                 if (laddr == NULL) {
 262                         if (error == 0)
 263                                 error = EADDRNOTAVAIL;
 264                         goto release;
 265                 }
 266                 if (in6p->in6p_lport == 0 &&
 267                     (error = in6_pcbsetport(laddr, in6p, p, 0)) != 0)
 268                         goto release;
 269         } else {
 270                 if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
 271                         error = ENOTCONN;
 272                         goto release;
 273                 }
 274                 if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) {
 275                         if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
 276                                 /*
 277                                  * XXX: this case would happen when the
 278                                  * application sets the V6ONLY flag after
 279                                  * connecting the foreign address.
 280                                  * Such applications should be fixed,
 281                                  * so we bark here.
 282                                  */
 283                                 log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
 284                                     "option was set for a connected socket\n");
 285                                 error = EINVAL;
 286                                 goto release;
 287                         } else
 288                                 af = AF_INET;
 289                 }
 290                 laddr = &in6p->in6p_laddr;
 291                 faddr = &in6p->in6p_faddr;
 292                 fport = in6p->in6p_fport;
 293         }
 294
 295         if (af == AF_INET)
 296                 hlen = sizeof(struct ip);
 297
 298         /*
 299          * Calculate data length and get a mbuf
 300          * for UDP and IP6 headers.
 301          */
 302         M_PREPEND(m, hlen + sizeof(struct udphdr), M_DONTWAIT);
 303         if (m == 0) {
 304                 error = ENOBUFS;
 305                 goto release;
 306         }
 307
 308         /*
 309          * Stuff checksum and output datagram.
 310          */
 311         udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
 312         udp6->uh_sport = in6p->in6p_lport; /* lport is always set in the PCB */
 313         udp6->uh_dport = fport;
 314         if (plen <= 0xffff)
 315                 udp6->uh_ulen = htons((u_short)plen);
 316         else
 317                 udp6->uh_ulen = 0;
 318         udp6->uh_sum = 0;
 319
 320         switch (af) {
 321         case AF_INET6:
 322                 ip6 = mtod(m, struct ip6_hdr *);
 323                 ip6->ip6_flow   = in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK;
 324                 ip6->ip6_vfc    &= ~IPV6_VERSION_MASK;
 325                 ip6->ip6_vfc    |= IPV6_VERSION;
 326 #if 0                           /* ip6_plen will be filled in ip6_output. */
 327                 ip6->ip6_plen   = htons((u_short)plen);
 328 #endif
 329                 ip6->ip6_nxt    = IPPROTO_UDP;
 330                 ip6->ip6_hlim   = in6_selecthlim(in6p,
 331                                                  in6p->in6p_route.ro_rt ?
 332                                                  in6p->in6p_route.ro_rt->rt_ifp : NULL);
 333                 ip6->ip6_src    = *laddr;
 334                 ip6->ip6_dst    = *faddr;
 335
 336                 if ((udp6->uh_sum = in6_cksum(m, IPPROTO_UDP,
 337                                 sizeof(struct ip6_hdr), plen)) == 0) {
 338                         udp6->uh_sum = 0xffff;
 339                 }
 340
 341                 flags = 0;
 342
 343                 udp6stat.udp6s_opackets++;
 344 #ifdef IPSEC
 345                 if (ipsec_bypass == 0 && ipsec_setsocket(m, in6p->in6p_socket) != 0) {
 346                         error = ENOBUFS;
 347                         goto release;
 348                 }
 349 #endif /*IPSEC*/
 350                 m->m_pkthdr.socket_id = get_socket_id(in6p->in6p_socket);
 351
 352 #if PKT_PRIORITY
 353                 set_traffic_class(m, in6p->in6p_socket, mtc);
 354 #endif /* PKT_PRIORITY */
 355                 error = ip6_output(m, in6p->in6p_outputopts, &in6p->in6p_route,
 356                     flags, in6p->in6p_moptions, NULL, 0);
 357
 358 #if IFNET_ROUTE_REFCNT
 359                 /*
 360                  * Always discard the cached route for unconnected socket
 361                  * or if it is a multicast route.
 362                  */
 363                 if (in6p->in6p_route.ro_rt != NULL &&
 364                     ((in6p->in6p_route.ro_rt->rt_flags & RTF_MULTICAST) ||
 365                     in6p->in6p_socket == NULL ||
 366                     in6p->in6p_socket->so_state != SS_ISCONNECTED)) {
 367                         rtfree(in6p->in6p_route.ro_rt);
 368                         in6p->in6p_route.ro_rt = NULL;
 369                 }
 370 #endif /* IFNET_ROUTE_REFCNT */
 371                 break;
 372         case AF_INET:
 373                 error = EAFNOSUPPORT;
 374                 goto release;
 375         }
 376         goto releaseopt;
 377
 378 release:
 379         m_freem(m);
 380
 381 releaseopt:
 382         if (control) {
 383                 ip6_clearpktopts(in6p->in6p_outputopts, 0, -1);
 384                 in6p->in6p_outputopts = stickyopt;
 385                 m_freem(control);
 386         }
 387         return(error);
 388 }