1 /*- 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $KAME: dest6.c,v 1.59 2003/07/11 13:21:16 t-momose Exp $ 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "opt_inet.h" 36 #include "opt_inet6.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/malloc.h> 41 #include <sys/mbuf.h> 42 #include <sys/domain.h> 43 #include <sys/protosw.h> 44 #include <sys/socket.h> 45 #include <sys/errno.h> 46 #include <sys/time.h> 47 #include <sys/kernel.h> 48 49 #include <net/if.h> 50 #include <net/if_var.h> 51 #include <net/route.h> 52 53 #include <netinet/in.h> 54 #include <netinet/in_var.h> 55 #include <netinet/ip6.h> 56 #include <netinet6/ip6_var.h> 57 #include <netinet/icmp6.h> 58 59 /* 60 * Destination options header processing. 61 */ 62 int 63 dest6_input(struct mbuf **mp, int *offp, int proto) 64 { 65 struct mbuf *m = *mp; 66 int off = *offp, dstoptlen, optlen; 67 struct ip6_dest *dstopts; 68 u_int8_t *opt; 69 70 /* validation of the length of the header */ 71 #ifndef PULLDOWN_TEST 72 IP6_EXTHDR_CHECK(m, off, sizeof(*dstopts), IPPROTO_DONE); 73 dstopts = (struct ip6_dest *)(mtod(m, caddr_t) + off); 74 #else 75 IP6_EXTHDR_GET(dstopts, struct ip6_dest *, m, off, sizeof(*dstopts)); 76 if (dstopts == NULL) 77 return IPPROTO_DONE; 78 #endif 79 dstoptlen = (dstopts->ip6d_len + 1) << 3; 80 81 #ifndef PULLDOWN_TEST 82 IP6_EXTHDR_CHECK(m, off, dstoptlen, IPPROTO_DONE); 83 dstopts = (struct ip6_dest *)(mtod(m, caddr_t) + off); 84 #else 85 IP6_EXTHDR_GET(dstopts, struct ip6_dest *, m, off, dstoptlen); 86 if (dstopts == NULL) 87 return IPPROTO_DONE; 88 #endif 89 off += dstoptlen; 90 dstoptlen -= sizeof(struct ip6_dest); 91 opt = (u_int8_t *)dstopts + sizeof(struct ip6_dest); 92 93 /* search header for all options. */ 94 for (optlen = 0; dstoptlen > 0; dstoptlen -= optlen, opt += optlen) { 95 if (*opt != IP6OPT_PAD1 && 96 (dstoptlen < IP6OPT_MINLEN || *(opt + 1) + 2 > dstoptlen)) { 97 IP6STAT_INC(ip6s_toosmall); 98 goto bad; 99 } 100 101 switch (*opt) { 102 case IP6OPT_PAD1: 103 optlen = 1; 104 break; 105 case IP6OPT_PADN: 106 optlen = *(opt + 1) + 2; 107 break; 108 default: /* unknown option */ 109 optlen = ip6_unknown_opt(opt, m, 110 opt - mtod(m, u_int8_t *)); 111 if (optlen == -1) 112 return (IPPROTO_DONE); 113 optlen += 2; 114 break; 115 } 116 } 117 118 *offp = off; 119 return (dstopts->ip6d_nxt); 120 121 bad: 122 m_freem(m); 123 return (IPPROTO_DONE); 124 } 125