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: route6.c,v 1.24 2001/03/14 03:07:05 itojun 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/mbuf.h> 40 #include <sys/socket.h> 41 #include <sys/systm.h> 42 #include <sys/queue.h> 43 44 #include <net/if.h> 45 46 #include <netinet/in.h> 47 #include <netinet6/in6_var.h> 48 #include <netinet/ip6.h> 49 #include <netinet6/ip6_var.h> 50 #include <netinet6/scope6_var.h> 51 52 #include <netinet/icmp6.h> 53 54 #if 0 55 static int ip6_rthdr0 __P((struct mbuf *, struct ip6_hdr *, 56 struct ip6_rthdr0 *)); 57 58 #endif /* Disable route header processing. */ 59 60 /* 61 * proto - is unused 62 */ 63 64 int 65 route6_input(struct mbuf **mp, int *offp, int proto) 66 { 67 struct ip6_hdr *ip6; 68 struct mbuf *m = *mp; 69 struct ip6_rthdr *rh; 70 int off = *offp, rhlen; 71 struct ip6aux *ip6a; 72 73 ip6a = ip6_findaux(m); 74 if (ip6a) { 75 /* XXX reject home-address option before rthdr */ 76 if (ip6a->ip6a_flags & IP6A_SWAP) { 77 ip6stat.ip6s_badoptions++; 78 m_freem(m); 79 return IPPROTO_DONE; 80 } 81 } 82 83 #ifndef PULLDOWN_TEST 84 IP6_EXTHDR_CHECK(m, off, sizeof(*rh), IPPROTO_DONE); 85 ip6 = mtod(m, struct ip6_hdr *); 86 rh = (struct ip6_rthdr *)((caddr_t)ip6 + off); 87 #else 88 ip6 = mtod(m, struct ip6_hdr *); 89 IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, sizeof(*rh)); 90 if (rh == NULL) { 91 ip6stat.ip6s_tooshort++; 92 return IPPROTO_DONE; 93 } 94 #endif 95 96 switch (rh->ip6r_type) { 97 #if 0 98 case IPV6_RTHDR_TYPE_0: 99 rhlen = (rh->ip6r_len + 1) << 3; 100 #ifndef PULLDOWN_TEST 101 /* 102 * note on option length: 103 * due to IP6_EXTHDR_CHECK assumption, we cannot handle 104 * very big routing header (max rhlen == 2048). 105 */ 106 IP6_EXTHDR_CHECK(m, off, rhlen, IPPROTO_DONE); 107 #else 108 /* 109 * note on option length: 110 * maximum rhlen: 2048 111 * max mbuf m_pulldown can handle: MCLBYTES == usually 2048 112 * so, here we are assuming that m_pulldown can handle 113 * rhlen == 2048 case. this may not be a good thing to 114 * assume - we may want to avoid pulling it up altogether. 115 */ 116 IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, rhlen); 117 if (rh == NULL) { 118 ip6stat.ip6s_tooshort++; 119 return IPPROTO_DONE; 120 } 121 #endif 122 if (ip6_rthdr0(m, ip6, (struct ip6_rthdr0 *)rh)) 123 return (IPPROTO_DONE); 124 break; 125 #endif /* Disable route header 0 */ 126 default: 127 /* unknown routing type */ 128 if (rh->ip6r_segleft == 0) { 129 rhlen = (rh->ip6r_len + 1) << 3; 130 break; /* Final dst. Just ignore the header. */ 131 } 132 ip6stat.ip6s_badoptions++; 133 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, 134 (caddr_t)&rh->ip6r_type - (caddr_t)ip6); 135 return (IPPROTO_DONE); 136 } 137 138 *offp += rhlen; 139 return (rh->ip6r_nxt); 140 } 141 142 /* 143 * Type0 routing header processing 144 * 145 * RFC2292 backward compatibility warning: no support for strict/loose bitmap, 146 * as it was dropped between RFC1883 and RFC2460. 147 */ 148 #if 0 149 static int 150 ip6_rthdr0(struct mbuf *m, struct ip6_hdr *ip6, struct ip6_rthdr0 *rh0) 151 { 152 int addrs, index; 153 struct in6_addr *nextaddr, tmpaddr; 154 struct in6_ifaddr *ifa; 155 156 if (rh0->ip6r0_segleft == 0) 157 return (0); 158 159 if (rh0->ip6r0_len % 2 160 #ifdef COMPAT_RFC1883 161 || rh0->ip6r0_len > 46 162 #endif 163 ) { 164 /* 165 * Type 0 routing header can't contain more than 23 addresses. 166 * RFC 2462: this limitation was removed since strict/loose 167 * bitmap field was deleted. 168 */ 169 ip6stat.ip6s_badoptions++; 170 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, 171 (caddr_t)&rh0->ip6r0_len - (caddr_t)ip6); 172 return (-1); 173 } 174 175 if ((addrs = rh0->ip6r0_len / 2) < rh0->ip6r0_segleft) { 176 ip6stat.ip6s_badoptions++; 177 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, 178 (caddr_t)&rh0->ip6r0_segleft - (caddr_t)ip6); 179 return (-1); 180 } 181 182 index = addrs - rh0->ip6r0_segleft; 183 rh0->ip6r0_segleft--; 184 nextaddr = ((struct in6_addr *)(rh0 + 1)) + index; 185 186 /* 187 * reject invalid addresses. be proactive about malicious use of 188 * IPv4 mapped/compat address. 189 * XXX need more checks? 190 */ 191 if (IN6_IS_ADDR_MULTICAST(nextaddr) || 192 IN6_IS_ADDR_UNSPECIFIED(nextaddr) || 193 IN6_IS_ADDR_V4MAPPED(nextaddr) || 194 IN6_IS_ADDR_V4COMPAT(nextaddr)) { 195 ip6stat.ip6s_badoptions++; 196 m_freem(m); 197 return (-1); 198 } 199 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 200 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst) || 201 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst) || 202 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 203 ip6stat.ip6s_badoptions++; 204 m_freem(m); 205 return (-1); 206 } 207 208 /* 209 * Determine the scope zone of the next hop, based on the interface 210 * of the current hop. [RFC4007, Section 9] 211 * Then disambiguate the scope zone for the next hop (if necessary). 212 */ 213 if ((ifa = ip6_getdstifaddr(m)) == NULL) 214 goto bad; 215 if (in6_setscope(nextaddr, ifa->ia_ifp, NULL) != 0) { 216 ip6stat.ip6s_badscope++; 217 goto bad; 218 } 219 220 /* 221 * Swap the IPv6 destination address and nextaddr. Forward the packet. 222 */ 223 tmpaddr = *nextaddr; 224 *nextaddr = ip6->ip6_dst; 225 in6_clearscope(nextaddr); /* XXX */ 226 ip6->ip6_dst = tmpaddr; 227 228 #ifdef COMPAT_RFC1883 229 if (rh0->ip6r0_slmap[index / 8] & (1 << (7 - (index % 8)))) 230 ip6_forward(m, IPV6_SRCRT_NEIGHBOR); 231 else 232 ip6_forward(m, IPV6_SRCRT_NOTNEIGHBOR); 233 #else 234 ip6_forward(m, 1); 235 #endif 236 237 return (-1); /* m would be freed in ip6_forward() */ 238 239 bad: 240 m_freem(m); 241 return (-1); 242 } 243 #endif 244