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/syslog.h>
  85
  86 #include <net/if.h>
  87 #include <net/route.h>
  88 #include <net/if_types.h>
  89
  90 #include <netinet/in.h>
  91 #include <netinet/in_var.h>
  92 #include <netinet/in_systm.h>
  93 #include <netinet/ip.h>
  94 #include <netinet/ip_var.h>
  95 #include <netinet/in_pcb.h>
  96 #include <netinet/udp.h>
  97 #include <netinet/udp_var.h>
  98 #include <netinet/ip6.h>
  99 #include <netinet6/ip6_var.h>
 100 #include <netinet6/in6_pcb.h>
 101 #include <netinet6/udp6_var.h>
 102 #include <netinet/icmp6.h>
 103 #include <netinet6/ip6protosw.h>
 104
 105 #ifdef IPSEC
 106 #include <netinet6/ipsec.h>
 107 #ifdef INET6
 108 #include <netinet6/ipsec6.h>
 109 #endif
 110 #endif /* IPSEC */
 111
 112 #include <net/net_osdep.h>
 113
 114 /*
 115  * UDP protocol inplementation.
 116  * Per RFC 768, August, 1980.
 117  */
 118
 119 #define in6pcb          inpcb
 120 #define udp6stat        udpstat
 121 #define udp6s_opackets  udps_opackets
 122
 123 int
 124 udp6_output(struct in6pcb *in6p, struct mbuf *m, struct sockaddr *addr6,
 125             struct mbuf *control, struct thread *td)
 126 {
 127         u_int32_t ulen = m->m_pkthdr.len;
 128         u_int32_t plen = sizeof(struct udphdr) + ulen;
 129         struct ip6_hdr *ip6;
 130         struct udphdr *udp6;
 131         struct in6_addr *laddr, *faddr;
 132         u_short fport;
 133         int error = 0;
 134         struct ip6_pktopts opt, *stickyopt = in6p->in6p_outputopts;
 135         int priv;
 136         int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
 137         int flags;
 138         struct sockaddr_in6 tmp;
 139
 140         priv = !suser(td);      /* 1 if privilaged, 0 if not */
 141         if (control) {
 142                 if ((error = ip6_setpktoptions(control, &opt,
 143                     in6p->in6p_outputopts,
 144                     IPPROTO_UDP, priv)) != 0)
 145                         goto release;
 146                 in6p->in6p_outputopts = &opt;
 147         }
 148
 149         if (addr6) {
 150                 /*
 151                  * IPv4 version of udp_output calls in_pcbconnect in this case,
 152                  * which needs splnet and affects performance.
 153                  * Since we saw no essential reason for calling in_pcbconnect,
 154                  * we get rid of such kind of logic, and call in6_selectsrc
 155                  * and in6_pcbsetport in order to fill in the local address
 156                  * and the local port.
 157                  */
 158                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)addr6;
 159                 if (sin6->sin6_port == 0) {
 160                         error = EADDRNOTAVAIL;
 161                         goto release;
 162                 }
 163
 164                 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
 165                         /* how about ::ffff:0.0.0.0 case? */
 166                         error = EISCONN;
 167                         goto release;
 168                 }
 169                 if (!prison_remote_ip(td, (struct sockaddr *)addr6)) {
 170                         error = EAFNOSUPPORT; /* IPv4 only jail */
 171                         goto release;
 172                 }
 173
 174                 /* protect *sin6 from overwrites */
 175                 tmp = *sin6;
 176                 sin6 = &tmp;
 177
 178                 faddr = &sin6->sin6_addr;
 179                 fport = sin6->sin6_port; /* allow 0 port */
 180
 181                 if (IN6_IS_ADDR_V4MAPPED(faddr)) {
 182                         if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
 183                                 /*
 184                                  * I believe we should explicitly discard the
 185                                  * packet when mapped addresses are disabled,
 186                                  * rather than send the packet as an IPv6 one.
 187                                  * If we chose the latter approach, the packet
 188                                  * might be sent out on the wire based on the
 189                                  * default route, the situation which we'd
 190                                  * probably want to avoid.
 191                                  * (20010421 jinmei@kame.net)
 192                                  */
 193                                 error = EINVAL;
 194                                 goto release;
 195                         } else
 196                                 af = AF_INET;
 197                 }
 198
 199                 /* KAME hack: embed scopeid */
 200                 if (in6_embedscope(&sin6->sin6_addr, sin6, in6p, NULL) != 0) {
 201                         error = EINVAL;
 202                         goto release;
 203                 }
 204
 205                 if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
 206                         laddr = in6_selectsrc(sin6, in6p->in6p_outputopts,
 207                                               in6p->in6p_moptions,
 208                                               &in6p->in6p_route,
 209                                               &in6p->in6p_laddr, &error, NULL);
 210                 } else
 211                         laddr = &in6p->in6p_laddr;      /* XXX */
 212                 if (laddr == NULL) {
 213                         if (error == 0)
 214                                 error = EADDRNOTAVAIL;
 215                         goto release;
 216                 }
 217                 if (in6p->in6p_lport == 0 &&
 218                     (error = in6_pcbsetport(laddr, in6p, td)) != 0)
 219                         goto release;
 220         } else {
 221                 if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
 222                         error = ENOTCONN;
 223                         goto release;
 224                 }
 225                 if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) {
 226                         if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
 227                                 /*
 228                                  * XXX: this case would happen when the
 229                                  * application sets the V6ONLY flag after
 230                                  * connecting the foreign address.
 231                                  * Such applications should be fixed,
 232                                  * so we bark here.
 233                                  */
 234                                 log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
 235                                     "option was set for a connected socket\n");
 236                                 error = EINVAL;
 237                                 goto release;
 238                         } else
 239                                 af = AF_INET;
 240                 }
 241                 laddr = &in6p->in6p_laddr;
 242                 faddr = &in6p->in6p_faddr;
 243                 fport = in6p->in6p_fport;
 244         }
 245
 246         if (af == AF_INET)
 247                 hlen = sizeof(struct ip);
 248
 249         /*
 250          * Calculate data length and get a mbuf
 251          * for UDP and IP6 headers.
 252          */
 253         M_PREPEND(m, hlen + sizeof(struct udphdr), MB_DONTWAIT);
 254         if (m == 0) {
 255                 error = ENOBUFS;
 256                 goto release;
 257         }
 258
 259         /*
 260          * Stuff checksum and output datagram.
 261          */
 262         udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
 263         udp6->uh_sport = in6p->in6p_lport; /* lport is always set in the PCB */
 264         udp6->uh_dport = fport;
 265         if (plen <= 0xffff)
 266                 udp6->uh_ulen = htons((u_short)plen);
 267         else
 268                 udp6->uh_ulen = 0;
 269         udp6->uh_sum = 0;
 270
 271         switch (af) {
 272         case AF_INET6:
 273                 ip6 = mtod(m, struct ip6_hdr *);
 274                 ip6->ip6_flow   = in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK;
 275                 ip6->ip6_vfc    &= ~IPV6_VERSION_MASK;
 276                 ip6->ip6_vfc    |= IPV6_VERSION;
 277 #if 0                           /* ip6_plen will be filled in ip6_output. */
 278                 ip6->ip6_plen   = htons((u_short)plen);
 279 #endif
 280                 ip6->ip6_nxt    = IPPROTO_UDP;
 281                 ip6->ip6_hlim   = in6_selecthlim(in6p,
 282                                                  in6p->in6p_route.ro_rt ?
 283                                                  in6p->in6p_route.ro_rt->rt_ifp : NULL);
 284                 ip6->ip6_src    = *laddr;
 285                 ip6->ip6_dst    = *faddr;
 286
 287                 if ((udp6->uh_sum = in6_cksum(m, IPPROTO_UDP,
 288                                 sizeof(struct ip6_hdr), plen)) == 0) {
 289                         udp6->uh_sum = 0xffff;
 290                 }
 291
 292                 flags = 0;
 293
 294                 udp6stat.udp6s_opackets++;
 295                 error = ip6_output(m, in6p->in6p_outputopts, &in6p->in6p_route,
 296                     flags, in6p->in6p_moptions, NULL, in6p);
 297                 break;
 298         case AF_INET:
 299                 error = EAFNOSUPPORT;
 300                 goto release;
 301         }
 302         goto releaseopt;
 303
 304 release:
 305         m_freem(m);
 306
 307 releaseopt:
 308         if (control) {
 309                 ip6_clearpktopts(in6p->in6p_outputopts, -1);
 310                 in6p->in6p_outputopts = stickyopt;
 311                 m_freem(control);
 312         }
 313         return (error);
 314 }