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 */
83int
84dest6_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
133bad:
134 *mp = NULL;
135 m_freem(m);
136 return IPPROTO_DONE;
137}
138