1/* $OpenBSD: dest6.c,v 1.20 2024/02/13 12:22:09 bluhm Exp $ */ 2/* $KAME: dest6.c,v 1.25 2001/02/22 01:39:16 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/mbuf.h> 36#include <sys/socket.h> 37#include <sys/errno.h> 38#include <sys/time.h> 39#include <sys/kernel.h> 40 41#include <net/route.h> 42 43#include <netinet/in.h> 44#include <netinet/ip6.h> 45#include <netinet6/ip6_var.h> 46#include <netinet/icmp6.h> 47 48/* 49 * Destination options header processing. 50 */ 51int 52dest6_input(struct mbuf **mp, int *offp, int proto, int af) 53{ 54 int off = *offp, dstoptlen, optlen; 55 struct ip6_dest *dstopts; 56 u_int8_t *opt; 57 58 /* validation of the length of the header */ 59 IP6_EXTHDR_GET(dstopts, struct ip6_dest *, *mp, off, sizeof(*dstopts)); 60 if (dstopts == NULL) 61 return IPPROTO_DONE; 62 dstoptlen = (dstopts->ip6d_len + 1) << 3; 63 64 IP6_EXTHDR_GET(dstopts, struct ip6_dest *, *mp, off, dstoptlen); 65 if (dstopts == NULL) 66 return IPPROTO_DONE; 67 off += dstoptlen; 68 dstoptlen -= sizeof(struct ip6_dest); 69 opt = (u_int8_t *)dstopts + sizeof(struct ip6_dest); 70 71 /* search header for all options. */ 72 for (optlen = 0; dstoptlen > 0; dstoptlen -= optlen, opt += optlen) { 73 if (*opt != IP6OPT_PAD1 && 74 (dstoptlen < IP6OPT_MINLEN || *(opt + 1) + 2 > dstoptlen)) { 75 ip6stat_inc(ip6s_toosmall); 76 goto bad; 77 } 78 79 switch (*opt) { 80 case IP6OPT_PAD1: 81 optlen = 1; 82 break; 83 case IP6OPT_PADN: 84 optlen = *(opt + 1) + 2; 85 break; 86 default: /* unknown option */ 87 optlen = ip6_unknown_opt(mp, opt, 88 opt - mtod(*mp, u_int8_t *)); 89 if (optlen == -1) 90 return (IPPROTO_DONE); 91 optlen += 2; 92 break; 93 } 94 } 95 96 *offp = off; 97 return (dstopts->ip6d_nxt); 98 99 bad: 100 m_freemp(mp); 101 return (IPPROTO_DONE); 102} 103