sys/netinet6/udp6_output.c

   1 /*      $FreeBSD: src/sys/netinet6/udp6_output.c,v 1.1.2.6 2003/01/23 21:06:47 sam Exp $        */
   2 /*      $DragonFly: src/sys/netinet6/udp6_output.c,v 1.9 2008/09/04 09:08:22 hasso Exp $        */
   3 /*      $KAME: udp6_output.c,v 1.31 2001/05/21 16:39:15 jinmei Exp $    */
   4
   5 /*
   6  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the project nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 /*
  35  * Copyright (c) 1982, 1986, 1989, 1993
  36  *      The Regents of the University of California.  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  * 3. All advertising materials mentioning features or use of this software
  47  *    must display the following acknowledgement:
  48  *      This product includes software developed by the University of
  49  *      California, Berkeley and its contributors.
  50  * 4. Neither the name of the University nor the names of its contributors
  51  *    may be used to endorse or promote products derived from this software
  52  *    without specific prior written permission.
  53  *
  54  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  55  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  56  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  57  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  58  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  59  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  60  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  61  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  62  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  63  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  64  * SUCH DAMAGE.
  65  *
  66  *      @(#)udp_var.h   8.1 (Berkeley) 6/10/93
  67  */
  68
  69 #include "opt_ipsec.h"
  70 #include "opt_inet.h"
  71 #include "opt_inet6.h"
  72
  73 #include <sys/param.h>
  74 #include <sys/malloc.h>
  75 #include <sys/mbuf.h>
  76 #include <sys/protosw.h>
  77 #include <sys/socket.h>
  78 #include <sys/socketvar.h>
  79 #include <sys/sysctl.h>
  80 #include <sys/errno.h>
  81 #include <sys/stat.h>
  82 #include <sys/systm.h>
  83 #include <sys/proc.h>
  84 #include <sys/priv.h>
  85 #include <sys/syslog.h>
  86
  87 #include <net/if.h>
  88 #include <net/route.h>
  89 #include <net/if_types.h>
  90
  91 #include <netinet/in.h>
  92 #include <netinet/in_var.h>
  93 #include <netinet/in_systm.h>
  94 #include <netinet/ip.h>
  95 #include <netinet/ip_var.h>
  96 #include <netinet/in_pcb.h>
  97 #include <netinet/udp.h>
  98 #include <netinet/udp_var.h>
  99 #include <netinet/ip6.h>
 100 #include <netinet6/ip6_var.h>
 101 #include <netinet6/in6_pcb.h>
 102 #include <netinet6/udp6_var.h>
 103 #include <netinet/icmp6.h>
 104 #include <netinet6/ip6protosw.h>
 105
 106 #ifdef IPSEC
 107 #include <netinet6/ipsec.h>
 108 #ifdef INET6
 109 #include <netinet6/ipsec6.h>
 110 #endif
 111 #endif /* IPSEC */
 112
 113 #include <net/net_osdep.h>
 114
 115 /*
 116  * UDP protocol inplementation.
 117  * Per RFC 768, August, 1980.
 118  */
 119
 120 #define in6pcb          inpcb
 121 #define udp6stat        udpstat
 122 #define udp6s_opackets  udps_opackets
 123
 124 int
 125 udp6_output(struct in6pcb *in6p, struct mbuf *m, struct sockaddr *addr6,
 126             struct mbuf *control, struct thread *td)
 127 {
 128         u_int32_t ulen = m->m_pkthdr.len;
 129         u_int32_t plen = sizeof(struct udphdr) + ulen;
 130         struct ip6_hdr *ip6;
 131         struct udphdr *udp6;
 132         struct in6_addr *laddr, *faddr;
 133         u_short fport;
 134         int error = 0;
 135         struct ip6_pktopts opt, *stickyopt = in6p->in6p_outputopts;
 136         int priv;
 137         int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
 138         int flags;
 139         struct sockaddr_in6 tmp;
 140
 141         priv = !priv_check(td, PRIV_ROOT);      /* 1 if privileged, 0 if not */
 142         if (control) {
 143                 if ((error = ip6_setpktoptions(control, &opt,
 144                     in6p->in6p_outputopts,
 145                     IPPROTO_UDP, priv)) != 0)
 146                         goto release;
 147                 in6p->in6p_outputopts = &opt;
 148         }
 149
 150         if (addr6) {
 151                 /*
 152                  * IPv4 version of udp_output calls in_pcbconnect in this case,
 153                  * which needs splnet and affects performance.
 154                  * Since we saw no essential reason for calling in_pcbconnect,
 155                  * we get rid of such kind of logic, and call in6_selectsrc
 156                  * and in6_pcbsetport in order to fill in the local address
 157                  * and the local port.
 158                  */
 159                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)addr6;
 160                 if (sin6->sin6_port == 0) {
 161                         error = EADDRNOTAVAIL;
 162                         goto release;
 163                 }
 164
 165                 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
 166                         /* how about ::ffff:0.0.0.0 case? */
 167                         error = EISCONN;
 168                         goto release;
 169                 }
 170                 if (!prison_remote_ip(td, (struct sockaddr *)addr6)) {
 171                         error = EAFNOSUPPORT; /* IPv4 only jail */
 172                         goto release;
 173                 }
 174
 175                 /* protect *sin6 from overwrites */
 176                 tmp = *sin6;
 177                 sin6 = &tmp;
 178
 179                 faddr = &sin6->sin6_addr;
 180                 fport = sin6->sin6_port; /* allow 0 port */
 181
 182                 if (IN6_IS_ADDR_V4MAPPED(faddr)) {
 183                         if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
 184                                 /*
 185                                  * I believe we should explicitly discard the
 186                                  * packet when mapped addresses are disabled,
 187                                  * rather than send the packet as an IPv6 one.
 188                                  * If we chose the latter approach, the packet
 189                                  * might be sent out on the wire based on the
 190                                  * default route, the situation which we'd
 191                                  * probably want to avoid.
 192                                  * (20010421 jinmei@kame.net)
 193                                  */
 194                                 error = EINVAL;
 195                                 goto release;
 196                         } else
 197                                 af = AF_INET;
 198                 }
 199
 200                 /* KAME hack: embed scopeid */
 201                 if (in6_embedscope(&sin6->sin6_addr, sin6, in6p, NULL) != 0) {
 202                         error = EINVAL;
 203                         goto release;
 204                 }
 205
 206                 if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
 207                         laddr = in6_selectsrc(sin6, in6p->in6p_outputopts,
 208                                               in6p->in6p_moptions,
 209                                               &in6p->in6p_route,
 210                                               &in6p->in6p_laddr, &error, NULL);
 211                 } else
 212                         laddr = &in6p->in6p_laddr;      /* XXX */
 213                 if (laddr == NULL) {
 214                         if (error == 0)
 215                                 error = EADDRNOTAVAIL;
 216                         goto release;
 217                 }
 218                 if (in6p->in6p_lport == 0 &&
 219                     (error = in6_pcbsetport(laddr, in6p, td)) != 0)
 220                         goto release;
 221         } else {
 222                 if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
 223                         error = ENOTCONN;
 224                         goto release;
 225                 }
 226                 if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) {
 227                         if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
 228                                 /*
 229                                  * XXX: this case would happen when the
 230                                  * application sets the V6ONLY flag after
 231                                  * connecting the foreign address.
 232                                  * Such applications should be fixed,
 233                                  * so we bark here.
 234                                  */
 235                                 log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
 236                                     "option was set for a connected socket\n");
 237                                 error = EINVAL;
 238                                 goto release;
 239                         } else
 240                                 af = AF_INET;
 241                 }
 242                 laddr = &in6p->in6p_laddr;
 243                 faddr = &in6p->in6p_faddr;
 244                 fport = in6p->in6p_fport;
 245         }
 246
 247         if (af == AF_INET)
 248                 hlen = sizeof(struct ip);
 249
 250         /*
 251          * Calculate data length and get a mbuf
 252          * for UDP and IP6 headers.
 253          */
 254         M_PREPEND(m, hlen + sizeof(struct udphdr), MB_DONTWAIT);
 255         if (m == 0) {
 256                 error = ENOBUFS;
 257                 goto release;
 258         }
 259
 260         /*
 261          * Stuff checksum and output datagram.
 262          */
 263         udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
 264         udp6->uh_sport = in6p->in6p_lport; /* lport is always set in the PCB */
 265         udp6->uh_dport = fport;
 266         if (plen <= 0xffff)
 267                 udp6->uh_ulen = htons((u_short)plen);
 268         else
 269                 udp6->uh_ulen = 0;
 270         udp6->uh_sum = 0;
 271
 272         switch (af) {
 273         case AF_INET6:
 274                 ip6 = mtod(m, struct ip6_hdr *);
 275                 ip6->ip6_flow   = in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK;
 276                 ip6->ip6_vfc    &= ~IPV6_VERSION_MASK;
 277                 ip6->ip6_vfc    |= IPV6_VERSION;
 278 #if 0                           /* ip6_plen will be filled in ip6_output. */
 279                 ip6->ip6_plen   = htons((u_short)plen);
 280 #endif
 281                 ip6->ip6_nxt    = IPPROTO_UDP;
 282                 ip6->ip6_hlim   = in6_selecthlim(in6p,
 283                                                  in6p->in6p_route.ro_rt ?
 284                                                  in6p->in6p_route.ro_rt->rt_ifp : NULL);
 285                 ip6->ip6_src    = *laddr;
 286                 ip6->ip6_dst    = *faddr;
 287
 288                 if ((udp6->uh_sum = in6_cksum(m, IPPROTO_UDP,
 289                                 sizeof(struct ip6_hdr), plen)) == 0) {
 290                         udp6->uh_sum = 0xffff;
 291                 }
 292
 293                 flags = 0;
 294
 295                 udp6stat.udp6s_opackets++;
 296                 error = ip6_output(m, in6p->in6p_outputopts, &in6p->in6p_route,
 297                     flags, in6p->in6p_moptions, NULL, in6p);
 298                 break;
 299         case AF_INET:
 300                 error = EAFNOSUPPORT;
 301                 goto release;
 302         }
 303         goto releaseopt;
 304
 305 release:
 306         m_freem(m);
 307
 308 releaseopt:
 309         if (control) {
 310                 ip6_clearpktopts(in6p->in6p_outputopts, -1);
 311                 in6p->in6p_outputopts = stickyopt;
 312                 m_freem(control);
 313         }
 314         return (error);
 315 }