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 /*      $KAME: udp6_output.c,v 1.31 2001/05/21 16:39:15 jinmei Exp $    */
   3
   4 /*
   5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of the project nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 /*
  34  * Copyright (c) 1982, 1986, 1989, 1993
  35  *      The Regents of the University of California.  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 University 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 REGENTS 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 REGENTS 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  *      @(#)udp_var.h   8.1 (Berkeley) 6/10/93
  62  */
  63
  64 #include "opt_inet.h"
  65 #include "opt_inet6.h"
  66
  67 #include <sys/param.h>
  68 #include <sys/malloc.h>
  69 #include <sys/mbuf.h>
  70 #include <sys/protosw.h>
  71 #include <sys/socket.h>
  72 #include <sys/socketvar.h>
  73 #include <sys/sysctl.h>
  74 #include <sys/errno.h>
  75 #include <sys/stat.h>
  76 #include <sys/systm.h>
  77 #include <sys/proc.h>
  78 #include <sys/caps.h>
  79 #include <sys/syslog.h>
  80 #include <sys/jail.h>
  81
  82 #include <net/if.h>
  83 #include <net/route.h>
  84 #include <net/if_types.h>
  85
  86 #include <netinet/in.h>
  87 #include <netinet/in_var.h>
  88 #include <netinet/in_systm.h>
  89 #include <netinet/ip.h>
  90 #include <netinet/ip_var.h>
  91 #include <netinet/in_pcb.h>
  92 #include <netinet/udp.h>
  93 #include <netinet/udp_var.h>
  94 #include <netinet/ip6.h>
  95 #include <netinet6/ip6_var.h>
  96 #include <netinet6/in6_pcb.h>
  97 #include <netinet6/udp6_var.h>
  98 #include <netinet/icmp6.h>
  99 #include <netinet6/ip6protosw.h>
 100
 101 #include <net/net_osdep.h>
 102
 103 /*
 104  * UDP protocol inplementation.
 105  * Per RFC 768, August, 1980.
 106  */
 107
 108 #define in6pcb          inpcb
 109 #define udp6stat        udp_stat
 110 #define udp6s_opackets  udps_opackets
 111
 112 int
 113 udp6_output(struct in6pcb *in6p, struct mbuf *m, struct sockaddr *addr6,
 114             struct mbuf *control, struct thread *td)
 115 {
 116         u_int32_t ulen = m->m_pkthdr.len;
 117         u_int32_t plen = sizeof(struct udphdr) + ulen;
 118         struct ip6_hdr *ip6;
 119         struct udphdr *udp6;
 120         struct in6_addr *laddr, *faddr;
 121         u_short fport;
 122         int error = 0;
 123         struct ip6_pktopts opt, *stickyopt = in6p->in6p_outputopts;
 124         int priv;
 125         int hlen = sizeof(struct ip6_hdr);
 126         struct sockaddr_in6 tmp;
 127
 128         /*
 129          * 1 if privileged, 0 if not
 130          */
 131         priv = !caps_priv_check_td(td, SYSCAP_RESTRICTEDROOT);
 132
 133         if (control) {
 134                 if ((error = ip6_setpktoptions(control, &opt,
 135                     in6p->in6p_outputopts,
 136                     IPPROTO_UDP, priv)) != 0)
 137                         goto release;
 138                 in6p->in6p_outputopts = &opt;
 139         }
 140
 141         if (addr6) {
 142                 /*
 143                  * IPv4 version of udp_output calls in_pcbconnect in this case,
 144                  * which needs splnet and affects performance.
 145                  * Since we saw no essential reason for calling in_pcbconnect,
 146                  * we get rid of such kind of logic, and call in6_selectsrc
 147                  * and in6_pcbsetlport in order to fill in the local address
 148                  * and the local port.
 149                  */
 150                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)addr6;
 151
 152                 /* Caller should have rejected the v4-mapped address */
 153                 KASSERT(!IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr),
 154                     ("v4-mapped address"));
 155
 156                 if (sin6->sin6_port == 0) {
 157                         error = EADDRNOTAVAIL;
 158                         goto release;
 159                 }
 160
 161                 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
 162                         /* how about ::ffff:0.0.0.0 case? */
 163                         error = EISCONN;
 164                         goto release;
 165                 }
 166                 if (!prison_remote_ip(td, addr6)) {
 167                         error = EAFNOSUPPORT; /* IPv4 only jail */
 168                         goto release;
 169                 }
 170
 171                 /* protect *sin6 from overwrites */
 172                 tmp = *sin6;
 173                 sin6 = &tmp;
 174
 175                 faddr = &sin6->sin6_addr;
 176                 fport = sin6->sin6_port; /* allow 0 port */
 177
 178                 /* KAME hack: embed scopeid */
 179                 if (in6_embedscope(&sin6->sin6_addr, sin6, in6p, NULL) != 0) {
 180                         error = EINVAL;
 181                         goto release;
 182                 }
 183
 184                 laddr = in6_selectsrc(sin6, in6p->in6p_outputopts,
 185                                       in6p->in6p_moptions,
 186                                       &in6p->in6p_route,
 187                                       &in6p->in6p_laddr, &error, NULL);
 188                 if (laddr == NULL) {
 189                         if (error == 0)
 190                                 error = EADDRNOTAVAIL;
 191                         goto release;
 192                 }
 193                 if (in6p->in6p_lport == 0) {
 194                         if ((error = in6_pcbsetlport(laddr, in6p, td)) != 0)
 195                                 goto release;
 196                         in_pcbinswildcardhash(in6p);
 197                 }
 198         } else {
 199                 if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
 200                         error = ENOTCONN;
 201                         goto release;
 202                 }
 203
 204                 /* Connection to v4-mapped address should have been rejected */
 205                 KASSERT(!IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr),
 206                     ("bound to v4-mapped address"));
 207
 208                 laddr = &in6p->in6p_laddr;
 209                 faddr = &in6p->in6p_faddr;
 210                 fport = in6p->in6p_fport;
 211         }
 212
 213         /*
 214          * Calculate data length and get a mbuf
 215          * for UDP and IP6 headers.
 216          */
 217         M_PREPEND(m, hlen + sizeof(struct udphdr), M_NOWAIT);
 218         if (m == NULL) {
 219                 error = ENOBUFS;
 220                 goto release;
 221         }
 222
 223         /*
 224          * Stuff checksum and output datagram.
 225          */
 226         udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
 227         udp6->uh_sport = in6p->in6p_lport; /* lport is always set in the PCB */
 228         udp6->uh_dport = fport;
 229         if (plen <= 0xffff)
 230                 udp6->uh_ulen = htons((u_short)plen);
 231         else
 232                 udp6->uh_ulen = 0;
 233         udp6->uh_sum = 0;
 234
 235         ip6 = mtod(m, struct ip6_hdr *);
 236         ip6->ip6_flow   = in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK;
 237         ip6->ip6_vfc    &= ~IPV6_VERSION_MASK;
 238         ip6->ip6_vfc    |= IPV6_VERSION;
 239 #if 0                           /* ip6_plen will be filled in ip6_output. */
 240         ip6->ip6_plen   = htons((u_short)plen);
 241 #endif
 242         ip6->ip6_nxt    = IPPROTO_UDP;
 243         ip6->ip6_hlim   = in6_selecthlim(in6p,
 244                                          in6p->in6p_route.ro_rt ?
 245                                          in6p->in6p_route.ro_rt->rt_ifp : NULL);
 246         ip6->ip6_src    = *laddr;
 247         ip6->ip6_dst    = *faddr;
 248
 249         if ((udp6->uh_sum = in6_cksum(m, IPPROTO_UDP,
 250                         sizeof(struct ip6_hdr), plen)) == 0) {
 251                 udp6->uh_sum = 0xffff;
 252         }
 253
 254         udp6stat.udp6s_opackets++;
 255         error = ip6_output(m, in6p->in6p_outputopts, &in6p->in6p_route, 0,
 256             in6p->in6p_moptions, NULL, in6p);
 257         goto releaseopt;
 258
 259 release:
 260         m_freem(m);
 261
 262 releaseopt:
 263         if (control) {
 264                 ip6_clearpktopts(in6p->in6p_outputopts, -1);
 265                 in6p->in6p_outputopts = stickyopt;
 266                 m_freem(control);
 267         }
 268         return (error);
 269 }