1 /* $OpenBSD: dest6.c,v 1.12 2013/10/17 16:27:45 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/malloc.h> 36 #include <sys/mbuf.h> 37 #include <sys/domain.h> 38 #include <sys/protosw.h> 39 #include <sys/socket.h> 40 #include <sys/errno.h> 41 #include <sys/time.h> 42 #include <sys/kernel.h> 43 44 #include <net/if.h> 45 #include <net/route.h> 46 47 #include <netinet/in.h> 48 #include <netinet/ip6.h> 49 #include <netinet6/ip6_var.h> 50 #include <netinet/icmp6.h> 51 52 /* 53 * Destination options header processing. 54 */ 55 int 56 dest6_input(struct mbuf **mp, int *offp, int proto) 57 { 58 struct mbuf *m = *mp; 59 int off = *offp, dstoptlen, optlen; 60 struct ip6_dest *dstopts; 61 u_int8_t *opt; 62 63 /* validation of the length of the header */ 64 IP6_EXTHDR_GET(dstopts, struct ip6_dest *, m, off, sizeof(*dstopts)); 65 if (dstopts == NULL) 66 return IPPROTO_DONE; 67 dstoptlen = (dstopts->ip6d_len + 1) << 3; 68 69 IP6_EXTHDR_GET(dstopts, struct ip6_dest *, m, off, dstoptlen); 70 if (dstopts == NULL) 71 return IPPROTO_DONE; 72 off += dstoptlen; 73 dstoptlen -= sizeof(struct ip6_dest); 74 opt = (u_int8_t *)dstopts + sizeof(struct ip6_dest); 75 76 /* search header for all options. */ 77 for (optlen = 0; dstoptlen > 0; dstoptlen -= optlen, opt += optlen) { 78 if (*opt != IP6OPT_PAD1 && 79 (dstoptlen < IP6OPT_MINLEN || *(opt + 1) + 2 > dstoptlen)) { 80 ip6stat.ip6s_toosmall++; 81 goto bad; 82 } 83 84 switch (*opt) { 85 case IP6OPT_PAD1: 86 optlen = 1; 87 break; 88 case IP6OPT_PADN: 89 optlen = *(opt + 1) + 2; 90 break; 91 default: /* unknown option */ 92 optlen = ip6_unknown_opt(opt, m, 93 opt - mtod(m, u_int8_t *)); 94 if (optlen == -1) 95 return (IPPROTO_DONE); 96 optlen += 2; 97 break; 98 } 99 } 100 101 *offp = off; 102 return (dstopts->ip6d_nxt); 103 104 bad: 105 m_freem(m); 106 return (IPPROTO_DONE); 107 } 108