bsd/netinet6/dest6.c

   1 /*
   2  * Copyright (c) 2020 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*      $FreeBSD: src/sys/netinet6/dest6.c,v 1.1.2.3 2001/07/03 11:01:49 ume Exp $      */
  29 /*      $KAME: dest6.c,v 1.27 2001/03/29 05:34:30 itojun Exp $  */
  30
  31 /*
  32  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
  33  * All rights reserved.
  34  *
  35  * Redistribution and use in source and binary forms, with or without
  36  * modification, are permitted provided that the following conditions
  37  * are met:
  38  * 1. Redistributions of source code must retain the above copyright
  39  *    notice, this list of conditions and the following disclaimer.
  40  * 2. Redistributions in binary form must reproduce the above copyright
  41  *    notice, this list of conditions and the following disclaimer in the
  42  *    documentation and/or other materials provided with the distribution.
  43  * 3. Neither the name of the project nor the names of its contributors
  44  *    may be used to endorse or promote products derived from this software
  45  *    without specific prior written permission.
  46  *
  47  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  48  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  49  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  50  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  51  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  52  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  53  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  54  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  55  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  56  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  57  * SUCH DAMAGE.
  58  */
  59
  60 #include <sys/param.h>
  61 #include <sys/systm.h>
  62 #include <sys/malloc.h>
  63 #include <sys/mbuf.h>
  64 #include <sys/domain.h>
  65 #include <sys/protosw.h>
  66 #include <sys/socket.h>
  67 #include <sys/errno.h>
  68 #include <sys/time.h>
  69 #include <sys/kernel.h>
  70
  71 #include <net/if.h>
  72 #include <net/route.h>
  73
  74 #include <netinet/in.h>
  75 #include <netinet/in_var.h>
  76 #include <netinet/ip6.h>
  77 #include <netinet6/ip6_var.h>
  78 #include <netinet/icmp6.h>
  79
  80 /*
  81  * Destination options header processing.
  82  */
  83 int
  84 dest6_input(struct mbuf **mp, int *offp, int proto)
  85 {
  86 #pragma unused(proto)
  87         struct mbuf *m = *mp;
  88         int off = *offp, dstoptlen = 0, optlen = 0;
  89         struct ip6_dest *dstopts = NULL;
  90         u_int8_t *opt = NULL;
  91
  92         /* validation of the length of the header */
  93         IP6_EXTHDR_CHECK(m, off, sizeof(*dstopts), return IPPROTO_DONE);
  94         dstopts = (struct ip6_dest *)(mtod(m, caddr_t) + off);
  95         dstoptlen = (dstopts->ip6d_len + 1) << 3;
  96
  97         IP6_EXTHDR_CHECK(m, off, dstoptlen, return IPPROTO_DONE);
  98         dstopts = (struct ip6_dest *)(mtod(m, caddr_t) + off);
  99         off += dstoptlen;
 100         dstoptlen -= sizeof(struct ip6_dest);
 101         opt = (u_int8_t *)dstopts + sizeof(struct ip6_dest);
 102
 103         /* search header for all options. */
 104         for (optlen = 0; dstoptlen > 0; dstoptlen -= optlen, opt += optlen) {
 105                 if (*opt != IP6OPT_PAD1 &&
 106                     (dstoptlen < IP6OPT_MINLEN || *(opt + 1) + 2 > dstoptlen)) {
 107                         ip6stat.ip6s_toosmall++;
 108                         goto bad;
 109                 }
 110
 111                 switch (*opt) {
 112                 case IP6OPT_PAD1:
 113                         optlen = 1;
 114                         break;
 115                 case IP6OPT_PADN:
 116                         optlen = *(opt + 1) + 2;
 117                         break;
 118
 119                 default:                /* unknown option */
 120                         optlen = ip6_unknown_opt(opt, m,
 121                             opt - mtod(m, u_int8_t *));
 122                         if (optlen == -1) {
 123                                 return IPPROTO_DONE;
 124                         }
 125                         optlen += 2;
 126                         break;
 127                 }
 128         }
 129         *mp = m;
 130         *offp = off;
 131         return dstopts->ip6d_nxt;
 132
 133 bad:
 134         *mp = NULL;
 135         m_freem(m);
 136         return IPPROTO_DONE;
 137 }