1 /* $NetBSD: route6.c,v 1.7 2000/09/20 23:35:51 itojun Exp $ */ 2 /* $KAME: route6.c,v 1.21 2000/09/20 23:00:49 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/mbuf.h> 35 #include <sys/socket.h> 36 #include <sys/systm.h> 37 38 #include <net/if.h> 39 40 #include <netinet/in.h> 41 #include <netinet6/in6_var.h> 42 #include <netinet/ip6.h> 43 #include <netinet6/ip6_var.h> 44 45 #include <netinet/icmp6.h> 46 47 static int ip6_rthdr0 __P((struct mbuf *, struct ip6_hdr *, struct ip6_rthdr0 *)); 48 49 int 50 route6_input(mp, offp, proto) 51 struct mbuf **mp; 52 int *offp, proto; /* proto is unused */ 53 { 54 register struct ip6_hdr *ip6; 55 register struct mbuf *m = *mp; 56 register struct ip6_rthdr *rh; 57 int off = *offp, rhlen; 58 59 #ifndef PULLDOWN_TEST 60 IP6_EXTHDR_CHECK(m, off, sizeof(*rh), IPPROTO_DONE); 61 ip6 = mtod(m, struct ip6_hdr *); 62 rh = (struct ip6_rthdr *)((caddr_t)ip6 + off); 63 #else 64 ip6 = mtod(m, struct ip6_hdr *); 65 IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, sizeof(*rh)); 66 if (rh == NULL) { 67 ip6stat.ip6s_tooshort++; 68 return IPPROTO_DONE; 69 } 70 #endif 71 72 switch(rh->ip6r_type) { 73 case IPV6_RTHDR_TYPE_0: 74 rhlen = (rh->ip6r_len + 1) << 3; 75 #ifndef PULLDOWN_TEST 76 IP6_EXTHDR_CHECK(m, off, rhlen, IPPROTO_DONE); 77 #else 78 IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, rhlen); 79 if (rh == NULL) { 80 ip6stat.ip6s_tooshort++; 81 return IPPROTO_DONE; 82 } 83 #endif 84 if (ip6_rthdr0(m, ip6, (struct ip6_rthdr0 *)rh)) 85 return(IPPROTO_DONE); 86 break; 87 default: 88 /* unknown routing type */ 89 if (rh->ip6r_segleft == 0) { 90 rhlen = (rh->ip6r_len + 1) << 3; 91 break; /* Final dst. Just ignore the header. */ 92 } 93 ip6stat.ip6s_badoptions++; 94 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, 95 (caddr_t)&rh->ip6r_type - (caddr_t)ip6); 96 return(IPPROTO_DONE); 97 } 98 99 *offp += rhlen; 100 return(rh->ip6r_nxt); 101 } 102 103 /* 104 * Type0 routing header processing 105 */ 106 static int 107 ip6_rthdr0(m, ip6, rh0) 108 struct mbuf *m; 109 struct ip6_hdr *ip6; 110 struct ip6_rthdr0 *rh0; 111 { 112 int addrs, index; 113 struct in6_addr *nextaddr, tmpaddr; 114 115 if (rh0->ip6r0_segleft == 0) 116 return(0); 117 118 if (rh0->ip6r0_len % 2 119 #ifdef COMPAT_RFC1883 120 || rh0->ip6r0_len > 46 121 #endif 122 ) { 123 /* 124 * Type 0 routing header can't contain more than 23 addresses. 125 * RFC 2462: this limitation was removed since stict/loose 126 * bitmap field was deleted. 127 */ 128 ip6stat.ip6s_badoptions++; 129 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, 130 (caddr_t)&rh0->ip6r0_len - (caddr_t)ip6); 131 return(-1); 132 } 133 134 if ((addrs = rh0->ip6r0_len / 2) < rh0->ip6r0_segleft) { 135 ip6stat.ip6s_badoptions++; 136 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, 137 (caddr_t)&rh0->ip6r0_segleft - (caddr_t)ip6); 138 return(-1); 139 } 140 141 index = addrs - rh0->ip6r0_segleft; 142 rh0->ip6r0_segleft--; 143 nextaddr = rh0->ip6r0_addr + index; 144 145 /* 146 * reject invalid addresses. be proactive about malicious use of 147 * IPv4 mapped/compat address. 148 * XXX need more checks? 149 */ 150 if (IN6_IS_ADDR_MULTICAST(nextaddr) || 151 IN6_IS_ADDR_UNSPECIFIED(nextaddr) || 152 IN6_IS_ADDR_V4MAPPED(nextaddr) || 153 IN6_IS_ADDR_V4COMPAT(nextaddr)) { 154 ip6stat.ip6s_badoptions++; 155 m_freem(m); 156 return(-1); 157 } 158 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 159 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst) || 160 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst) || 161 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 162 ip6stat.ip6s_badoptions++; 163 m_freem(m); 164 return(-1); 165 } 166 167 /* 168 * Swap the IPv6 destination address and nextaddr. Forward the packet. 169 */ 170 tmpaddr = *nextaddr; 171 *nextaddr = ip6->ip6_dst; 172 if (IN6_IS_ADDR_LINKLOCAL(nextaddr)) 173 nextaddr->s6_addr16[1] = 0; 174 ip6->ip6_dst = tmpaddr; 175 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) 176 ip6->ip6_dst.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index); 177 178 #ifdef COMPAT_RFC1883 179 if (rh0->ip6r0_slmap[index / 8] & (1 << (7 - (index % 8)))) 180 ip6_forward(m, IPV6_SRCRT_NEIGHBOR); 181 else 182 ip6_forward(m, IPV6_SRCRT_NOTNEIGHBOR); 183 #else 184 ip6_forward(m, 1); 185 #endif 186 187 return(-1); /* m would be freed in ip6_forward() */ 188 } 189