Line data    Source code

       1             : /*      $OpenBSD: dest6.c,v 1.17 2017/04/14 20:46:31 bluhm Exp $        */
       2             : /*      $KAME: dest6.c,v 1.25 2001/02/22 01:39:16 itojun 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             : #include <sys/param.h>
      34             : #include <sys/systm.h>
      35             : #include <sys/mbuf.h>
      36             : #include <sys/domain.h>
      37             : #include <sys/protosw.h>
      38             : #include <sys/socket.h>
      39             : #include <sys/errno.h>
      40             : #include <sys/time.h>
      41             : #include <sys/kernel.h>
      42             : 
      43             : #include <netinet/in.h>
      44             : #include <netinet/ip6.h>
      45             : #include <netinet6/ip6_var.h>
      46             : #include <netinet/icmp6.h>
      47             : 
      48             : /*
      49             :  * Destination options header processing.
      50             :  */
      51             : int
      52           0 : dest6_input(struct mbuf **mp, int *offp, int proto, int af)
      53             : {
      54           0 :         struct mbuf *m = *mp;
      55           0 :         int off = *offp, dstoptlen, optlen;
      56             :         struct ip6_dest *dstopts;
      57             :         u_int8_t *opt;
      58             : 
      59             :         /* validation of the length of the header */
      60           0 :         IP6_EXTHDR_GET(dstopts, struct ip6_dest *, m, off, sizeof(*dstopts));
      61           0 :         if (dstopts == NULL)
      62           0 :                 return IPPROTO_DONE;
      63           0 :         dstoptlen = (dstopts->ip6d_len + 1) << 3;
      64             : 
      65           0 :         IP6_EXTHDR_GET(dstopts, struct ip6_dest *, m, off, dstoptlen);
      66           0 :         if (dstopts == NULL)
      67           0 :                 return IPPROTO_DONE;
      68             :         off += dstoptlen;
      69           0 :         dstoptlen -= sizeof(struct ip6_dest);
      70           0 :         opt = (u_int8_t *)dstopts + sizeof(struct ip6_dest);
      71             : 
      72             :         /* search header for all options. */
      73           0 :         for (optlen = 0; dstoptlen > 0; dstoptlen -= optlen, opt += optlen) {
      74           0 :                 if (*opt != IP6OPT_PAD1 &&
      75           0 :                     (dstoptlen < IP6OPT_MINLEN || *(opt + 1) + 2 > dstoptlen)) {
      76           0 :                         ip6stat_inc(ip6s_toosmall);
      77             :                         goto bad;
      78             :                 }
      79             : 
      80           0 :                 switch (*opt) {
      81             :                 case IP6OPT_PAD1:
      82             :                         optlen = 1;
      83           0 :                         break;
      84             :                 case IP6OPT_PADN:
      85           0 :                         optlen = *(opt + 1) + 2;
      86           0 :                         break;
      87             :                 default:                /* unknown option */
      88           0 :                         optlen = ip6_unknown_opt(opt, m,
      89           0 :                             opt - mtod(m, u_int8_t *));
      90           0 :                         if (optlen == -1)
      91           0 :                                 return (IPPROTO_DONE);
      92           0 :                         optlen += 2;
      93           0 :                         break;
      94             :                 }
      95             :         }
      96             : 
      97           0 :         *offp = off;
      98           0 :         return (dstopts->ip6d_nxt);
      99             : 
     100             :   bad:
     101           0 :         m_freem(m);
     102           0 :         return (IPPROTO_DONE);
     103           0 : }