1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * $KAME: dest6.c,v 1.59 2003/07/11 13:21:16 t-momose Exp $ 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include "opt_inet.h" 38 #include "opt_inet6.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/malloc.h> 43 #include <sys/mbuf.h> 44 #include <sys/domain.h> 45 #include <sys/protosw.h> 46 #include <sys/socket.h> 47 #include <sys/errno.h> 48 #include <sys/time.h> 49 #include <sys/kernel.h> 50 51 #include <net/if.h> 52 #include <net/if_var.h> 53 #include <net/route.h> 54 55 #include <netinet/in.h> 56 #include <netinet/in_var.h> 57 #include <netinet/ip6.h> 58 #include <netinet6/ip6_var.h> 59 #include <netinet/icmp6.h> 60 61 /* 62 * Destination options header processing. 63 */ 64 int 65 dest6_input(struct mbuf **mp, int *offp, int proto) 66 { 67 struct mbuf *m; 68 int off, dstoptlen, optlen; 69 struct ip6_dest *dstopts; 70 u_int8_t *opt; 71 72 m = *mp; 73 off = *offp; 74 75 /* Validation of the length of the header. */ 76 if (m->m_len < off + sizeof(*dstopts)) { 77 m = m_pullup(m, off + sizeof(*dstopts)); 78 if (m == NULL) { 79 IP6STAT_INC(ip6s_exthdrtoolong); 80 *mp = m; 81 return (IPPROTO_DONE); 82 } 83 } 84 dstopts = (struct ip6_dest *)(mtod(m, caddr_t) + off); 85 dstoptlen = (dstopts->ip6d_len + 1) << 3; 86 87 if (m->m_len < off + dstoptlen) { 88 m = m_pullup(m, off + dstoptlen); 89 if (m == NULL) { 90 IP6STAT_INC(ip6s_exthdrtoolong); 91 *mp = m; 92 return (IPPROTO_DONE); 93 } 94 } 95 dstopts = (struct ip6_dest *)(mtod(m, caddr_t) + off); 96 off += dstoptlen; 97 dstoptlen -= sizeof(struct ip6_dest); 98 opt = (u_int8_t *)dstopts + sizeof(struct ip6_dest); 99 100 /* search header for all options. */ 101 for (; dstoptlen > 0; dstoptlen -= optlen, opt += optlen) { 102 if (*opt != IP6OPT_PAD1 && 103 (dstoptlen < IP6OPT_MINLEN || *(opt + 1) + 2 > dstoptlen)) { 104 IP6STAT_INC(ip6s_toosmall); 105 goto bad; 106 } 107 108 switch (*opt) { 109 case IP6OPT_PAD1: 110 optlen = 1; 111 break; 112 case IP6OPT_PADN: 113 optlen = *(opt + 1) + 2; 114 break; 115 default: /* unknown option */ 116 optlen = ip6_unknown_opt(opt, m, 117 opt - mtod(m, u_int8_t *)); 118 if (optlen == -1) { 119 *mp = NULL; 120 return (IPPROTO_DONE); 121 } 122 optlen += 2; 123 break; 124 } 125 } 126 127 *offp = off; 128 *mp = m; 129 return (dstopts->ip6d_nxt); 130 131 bad: 132 m_freem(m); 133 *mp = NULL; 134 return (IPPROTO_DONE); 135 } 136