sys/netinet6/dest6.c

   1 /*-
   2  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the project nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  *      $KAME: dest6.c,v 1.59 2003/07/11 13:21:16 t-momose Exp $
  30  */
  31
  32 #include <sys/cdefs.h>
  33 __FBSDID("$FreeBSD$");
  34
  35 #include "opt_inet.h"
  36 #include "opt_inet6.h"
  37
  38 #include <sys/param.h>
  39 #include <sys/systm.h>
  40 #include <sys/malloc.h>
  41 #include <sys/mbuf.h>
  42 #include <sys/domain.h>
  43 #include <sys/protosw.h>
  44 #include <sys/socket.h>
  45 #include <sys/errno.h>
  46 #include <sys/time.h>
  47 #include <sys/kernel.h>
  48 #include <sys/vimage.h>
  49
  50 #include <net/if.h>
  51 #include <net/route.h>
  52
  53 #include <netinet/in.h>
  54 #include <netinet/in_var.h>
  55 #include <netinet/ip6.h>
  56 #include <netinet6/ip6_var.h>
  57 #include <netinet/icmp6.h>
  58
  59 /*
  60  * Destination options header processing.
  61  */
  62 int
  63 dest6_input(struct mbuf **mp, int *offp, int proto)
  64 {
  65         struct mbuf *m = *mp;
  66         int off = *offp, dstoptlen, optlen;
  67         struct ip6_dest *dstopts;
  68         u_int8_t *opt;
  69
  70         /* validation of the length of the header */
  71 #ifndef PULLDOWN_TEST
  72         IP6_EXTHDR_CHECK(m, off, sizeof(*dstopts), IPPROTO_DONE);
  73         dstopts = (struct ip6_dest *)(mtod(m, caddr_t) + off);
  74 #else
  75         IP6_EXTHDR_GET(dstopts, struct ip6_dest *, m, off, sizeof(*dstopts));
  76         if (dstopts == NULL)
  77                 return IPPROTO_DONE;
  78 #endif
  79         dstoptlen = (dstopts->ip6d_len + 1) << 3;
  80
  81 #ifndef PULLDOWN_TEST
  82         IP6_EXTHDR_CHECK(m, off, dstoptlen, IPPROTO_DONE);
  83         dstopts = (struct ip6_dest *)(mtod(m, caddr_t) + off);
  84 #else
  85         IP6_EXTHDR_GET(dstopts, struct ip6_dest *, m, off, dstoptlen);
  86         if (dstopts == NULL)
  87                 return IPPROTO_DONE;
  88 #endif
  89         off += dstoptlen;
  90         dstoptlen -= sizeof(struct ip6_dest);
  91         opt = (u_int8_t *)dstopts + sizeof(struct ip6_dest);
  92
  93         /* search header for all options. */
  94         for (optlen = 0; dstoptlen > 0; dstoptlen -= optlen, opt += optlen) {
  95                 if (*opt != IP6OPT_PAD1 &&
  96                     (dstoptlen < IP6OPT_MINLEN || *(opt + 1) + 2 > dstoptlen)) {
  97                         V_ip6stat.ip6s_toosmall++;
  98                         goto bad;
  99                 }
 100
 101                 switch (*opt) {
 102                 case IP6OPT_PAD1:
 103                         optlen = 1;
 104                         break;
 105                 case IP6OPT_PADN:
 106                         optlen = *(opt + 1) + 2;
 107                         break;
 108                 default:                /* unknown option */
 109                         optlen = ip6_unknown_opt(opt, m,
 110                             opt - mtod(m, u_int8_t *));
 111                         if (optlen == -1)
 112                                 return (IPPROTO_DONE);
 113                         optlen += 2;
 114                         break;
 115                 }
 116         }
 117
 118         *offp = off;
 119         return (dstopts->ip6d_nxt);
 120
 121   bad:
 122         m_freem(m);
 123         return (IPPROTO_DONE);
 124 }