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 #ifndef PULLDOWN_TEST 77 IP6_EXTHDR_CHECK(m, off, sizeof(*dstopts), IPPROTO_DONE); 78 dstopts = (struct ip6_dest *)(mtod(m, caddr_t) + off); 79 #else 80 IP6_EXTHDR_GET(dstopts, struct ip6_dest *, m, off, sizeof(*dstopts)); 81 if (dstopts == NULL) 82 return IPPROTO_DONE; 83 #endif 84 dstoptlen = (dstopts->ip6d_len + 1) << 3; 85 86 #ifndef PULLDOWN_TEST 87 IP6_EXTHDR_CHECK(m, off, dstoptlen, IPPROTO_DONE); 88 dstopts = (struct ip6_dest *)(mtod(m, caddr_t) + off); 89 #else 90 IP6_EXTHDR_GET(dstopts, struct ip6_dest *, m, off, dstoptlen); 91 if (dstopts == NULL) 92 return IPPROTO_DONE; 93 #endif 94 off += dstoptlen; 95 dstoptlen -= sizeof(struct ip6_dest); 96 opt = (u_int8_t *)dstopts + sizeof(struct ip6_dest); 97 98 /* search header for all options. */ 99 for (; dstoptlen > 0; dstoptlen -= optlen, opt += optlen) { 100 if (*opt != IP6OPT_PAD1 && 101 (dstoptlen < IP6OPT_MINLEN || *(opt + 1) + 2 > dstoptlen)) { 102 IP6STAT_INC(ip6s_toosmall); 103 goto bad; 104 } 105 106 switch (*opt) { 107 case IP6OPT_PAD1: 108 optlen = 1; 109 break; 110 case IP6OPT_PADN: 111 optlen = *(opt + 1) + 2; 112 break; 113 default: /* unknown option */ 114 optlen = ip6_unknown_opt(opt, m, 115 opt - mtod(m, u_int8_t *)); 116 if (optlen == -1) 117 return (IPPROTO_DONE); 118 optlen += 2; 119 break; 120 } 121 } 122 123 *offp = off; 124 return (dstopts->ip6d_nxt); 125 126 bad: 127 m_freem(m); 128 return (IPPROTO_DONE); 129 } 130