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 1.8 2006/12/29 18:02:56 victor 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, priv, 0)) != 0)
 143                         goto release;
 144                 in6p->in6p_outputopts = &opt;
 145         }
 146
 147         if (addr6) {
 148                 /*
 149                  * IPv4 version of udp_output calls in_pcbconnect in this case,
 150                  * which needs splnet and affects performance.
 151                  * Since we saw no essential reason for calling in_pcbconnect,
 152                  * we get rid of such kind of logic, and call in6_selectsrc
 153                  * and in6_pcbsetport in order to fill in the local address
 154                  * and the local port.
 155                  */
 156                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)addr6;
 157                 if (sin6->sin6_port == 0) {
 158                         error = EADDRNOTAVAIL;
 159                         goto release;
 160                 }
 161
 162                 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
 163                         /* how about ::ffff:0.0.0.0 case? */
 164                         error = EISCONN;
 165                         goto release;
 166                 }
 167                 if (!prison_remote_ip(td, (struct sockaddr *)addr6)) {
 168                         error = EAFNOSUPPORT; /* IPv4 only jail */
 169                         goto release;
 170                 }
 171
 172                 /* protect *sin6 from overwrites */
 173                 tmp = *sin6;
 174                 sin6 = &tmp;
 175
 176                 faddr = &sin6->sin6_addr;
 177                 fport = sin6->sin6_port; /* allow 0 port */
 178
 179                 if (IN6_IS_ADDR_V4MAPPED(faddr)) {
 180                         if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
 181                                 /*
 182                                  * I believe we should explicitly discard the
 183                                  * packet when mapped addresses are disabled,
 184                                  * rather than send the packet as an IPv6 one.
 185                                  * If we chose the latter approach, the packet
 186                                  * might be sent out on the wire based on the
 187                                  * default route, the situation which we'd
 188                                  * probably want to avoid.
 189                                  * (20010421 jinmei@kame.net)
 190                                  */
 191                                 error = EINVAL;
 192                                 goto release;
 193                         } else
 194                                 af = AF_INET;
 195                 }
 196
 197                 /* KAME hack: embed scopeid */
 198                 if (in6_embedscope(&sin6->sin6_addr, sin6, in6p, NULL) != 0) {
 199                         error = EINVAL;
 200                         goto release;
 201                 }
 202
 203                 if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
 204                         laddr = in6_selectsrc(sin6, in6p->in6p_outputopts,
 205                                               in6p->in6p_moptions,
 206                                               &in6p->in6p_route,
 207                                               &in6p->in6p_laddr, &error, NULL);
 208                 } else
 209                         laddr = &in6p->in6p_laddr;      /* XXX */
 210                 if (laddr == NULL) {
 211                         if (error == 0)
 212                                 error = EADDRNOTAVAIL;
 213                         goto release;
 214                 }
 215                 if (in6p->in6p_lport == 0 &&
 216                     (error = in6_pcbsetport(laddr, in6p, td)) != 0)
 217                         goto release;
 218         } else {
 219                 if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
 220                         error = ENOTCONN;
 221                         goto release;
 222                 }
 223                 if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) {
 224                         if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
 225                                 /*
 226                                  * XXX: this case would happen when the
 227                                  * application sets the V6ONLY flag after
 228                                  * connecting the foreign address.
 229                                  * Such applications should be fixed,
 230                                  * so we bark here.
 231                                  */
 232                                 log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
 233                                     "option was set for a connected socket\n");
 234                                 error = EINVAL;
 235                                 goto release;
 236                         } else
 237                                 af = AF_INET;
 238                 }
 239                 laddr = &in6p->in6p_laddr;
 240                 faddr = &in6p->in6p_faddr;
 241                 fport = in6p->in6p_fport;
 242         }
 243
 244         if (af == AF_INET)
 245                 hlen = sizeof(struct ip);
 246
 247         /*
 248          * Calculate data length and get a mbuf
 249          * for UDP and IP6 headers.
 250          */
 251         M_PREPEND(m, hlen + sizeof(struct udphdr), MB_DONTWAIT);
 252         if (m == 0) {
 253                 error = ENOBUFS;
 254                 goto release;
 255         }
 256
 257         /*
 258          * Stuff checksum and output datagram.
 259          */
 260         udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
 261         udp6->uh_sport = in6p->in6p_lport; /* lport is always set in the PCB */
 262         udp6->uh_dport = fport;
 263         if (plen <= 0xffff)
 264                 udp6->uh_ulen = htons((u_short)plen);
 265         else
 266                 udp6->uh_ulen = 0;
 267         udp6->uh_sum = 0;
 268
 269         switch (af) {
 270         case AF_INET6:
 271                 ip6 = mtod(m, struct ip6_hdr *);
 272                 ip6->ip6_flow   = in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK;
 273                 ip6->ip6_vfc    &= ~IPV6_VERSION_MASK;
 274                 ip6->ip6_vfc    |= IPV6_VERSION;
 275 #if 0                           /* ip6_plen will be filled in ip6_output. */
 276                 ip6->ip6_plen   = htons((u_short)plen);
 277 #endif
 278                 ip6->ip6_nxt    = IPPROTO_UDP;
 279                 ip6->ip6_hlim   = in6_selecthlim(in6p,
 280                                                  in6p->in6p_route.ro_rt ?
 281                                                  in6p->in6p_route.ro_rt->rt_ifp : NULL);
 282                 ip6->ip6_src    = *laddr;
 283                 ip6->ip6_dst    = *faddr;
 284
 285                 if ((udp6->uh_sum = in6_cksum(m, IPPROTO_UDP,
 286                                 sizeof(struct ip6_hdr), plen)) == 0) {
 287                         udp6->uh_sum = 0xffff;
 288                 }
 289
 290                 flags = 0;
 291
 292                 udp6stat.udp6s_opackets++;
 293                 error = ip6_output(m, in6p->in6p_outputopts, &in6p->in6p_route,
 294                     flags, in6p->in6p_moptions, NULL, in6p);
 295                 break;
 296         case AF_INET:
 297                 error = EAFNOSUPPORT;
 298                 goto release;
 299         }
 300         goto releaseopt;
 301
 302 release:
 303         m_freem(m);
 304
 305 releaseopt:
 306         if (control) {
 307                 ip6_clearpktopts(in6p->in6p_outputopts, 0, -1);
 308                 in6p->in6p_outputopts = stickyopt;
 309                 m_freem(control);
 310         }
 311         return (error);
 312 }