1 /* $OpenBSD: dest6.c,v 1.19 2022/06/29 22:45:24 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 <netinet/in.h> 42 #include <netinet/ip6.h> 43 #include <netinet6/ip6_var.h> 44 #include <netinet/icmp6.h> 45 46 /* 47 * Destination options header processing. 48 */ 49 int 50 dest6_input(struct mbuf **mp, int *offp, int proto, int af) 51 { 52 int off = *offp, dstoptlen, optlen; 53 struct ip6_dest *dstopts; 54 u_int8_t *opt; 55 56 /* validation of the length of the header */ 57 IP6_EXTHDR_GET(dstopts, struct ip6_dest *, *mp, off, sizeof(*dstopts)); 58 if (dstopts == NULL) 59 return IPPROTO_DONE; 60 dstoptlen = (dstopts->ip6d_len + 1) << 3; 61 62 IP6_EXTHDR_GET(dstopts, struct ip6_dest *, *mp, off, dstoptlen); 63 if (dstopts == NULL) 64 return IPPROTO_DONE; 65 off += dstoptlen; 66 dstoptlen -= sizeof(struct ip6_dest); 67 opt = (u_int8_t *)dstopts + sizeof(struct ip6_dest); 68 69 /* search header for all options. */ 70 for (optlen = 0; dstoptlen > 0; dstoptlen -= optlen, opt += optlen) { 71 if (*opt != IP6OPT_PAD1 && 72 (dstoptlen < IP6OPT_MINLEN || *(opt + 1) + 2 > dstoptlen)) { 73 ip6stat_inc(ip6s_toosmall); 74 goto bad; 75 } 76 77 switch (*opt) { 78 case IP6OPT_PAD1: 79 optlen = 1; 80 break; 81 case IP6OPT_PADN: 82 optlen = *(opt + 1) + 2; 83 break; 84 default: /* unknown option */ 85 optlen = ip6_unknown_opt(mp, opt, 86 opt - mtod(*mp, u_int8_t *)); 87 if (optlen == -1) 88 return (IPPROTO_DONE); 89 optlen += 2; 90 break; 91 } 92 } 93 94 *offp = off; 95 return (dstopts->ip6d_nxt); 96 97 bad: 98 m_freemp(mp); 99 return (IPPROTO_DONE); 100 } 101