1/* $FreeBSD: src/sys/netinet6/dest6.c,v 1.1.2.3 2001/07/03 11:01:49 ume Exp $ */
2/* $KAME: dest6.c,v 1.27 2001/03/29 05:34:30 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/malloc.h>
36#include <sys/mbuf.h>
37#include <sys/domain.h>
38#include <sys/protosw.h>
39#include <sys/socket.h>
40#include <sys/errno.h>
41#include <sys/time.h>
42#include <sys/kernel.h>
43
44#include <net/if.h>
45#include <net/route.h>
46
47#include <netinet/in.h>
48#include <netinet/in_var.h>
49#include <netinet/ip6.h>
50#include <netinet6/ip6_var.h>
51#include <netinet/icmp6.h>
52
53/*
54 * Destination options header processing.
55 */
56int
57dest6_input(struct mbuf **mp, int *offp, int proto)
58{
59#pragma unused(proto)
60 struct mbuf *m = *mp;
61 int off = *offp, dstoptlen, optlen;
62 struct ip6_dest *dstopts;
63 u_int8_t *opt;
64
65 /* validation of the length of the header */
66 IP6_EXTHDR_CHECK(m, off, sizeof(*dstopts), return IPPROTO_DONE);
67 dstopts = (struct ip6_dest *)(mtod(m, caddr_t) + off);
68 dstoptlen = (dstopts->ip6d_len + 1) << 3;
69
70 IP6_EXTHDR_CHECK(m, off, dstoptlen, return IPPROTO_DONE);
71 dstopts = (struct ip6_dest *)(mtod(m, caddr_t) + off);
72 off += dstoptlen;
73 dstoptlen -= sizeof(struct ip6_dest);
74 opt = (u_int8_t *)dstopts + sizeof(struct ip6_dest);
75
76 /* search header for all options. */
77 for (optlen = 0; dstoptlen > 0; dstoptlen -= optlen, opt += optlen) {
78 if (*opt != IP6OPT_PAD1 &&
79 (dstoptlen < IP6OPT_MINLEN || *(opt + 1) + 2 > dstoptlen)) {
80 ip6stat.ip6s_toosmall++;
81 goto bad;
82 }
83
84 switch (*opt) {
85 case IP6OPT_PAD1:
86 optlen = 1;
87 break;
88 case IP6OPT_PADN:
89 optlen = *(opt + 1) + 2;
90 break;
91
92 default: /* unknown option */
93 optlen = ip6_unknown_opt(opt, m,
94 opt - mtod(m, u_int8_t *));
95 if (optlen == -1)
96 return (IPPROTO_DONE);
97 optlen += 2;
98 break;
99 }
100 }
101
102 *offp = off;
103 return (dstopts->ip6d_nxt);
104
105 bad:
106 m_freem(m);
107 return (IPPROTO_DONE);
108}
109