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 #include <sys/vimage.h> 44 45 #include <net/if.h> 46 47 #include <netinet/in.h> 48 #include <netinet6/in6_var.h> 49 #include <netinet/ip6.h> 50 #include <netinet6/ip6_var.h> 51 #include <netinet6/scope6_var.h> 52 53 #include <netinet/icmp6.h> 54 55 #if 0 56 static int ip6_rthdr0 __P((struct mbuf *, struct ip6_hdr *, 57 struct ip6_rthdr0 *)); 58 59 #endif /* Disable route header processing. */ 60 61 /* 62 * proto - is unused 63 */ 64 65 int 66 route6_input(struct mbuf **mp, int *offp, int proto) 67 { 68 INIT_VNET_INET6(curvnet); 69 struct ip6_hdr *ip6; 70 struct mbuf *m = *mp; 71 struct ip6_rthdr *rh; 72 int off = *offp, rhlen; 73 struct ip6aux *ip6a; 74 75 ip6a = ip6_findaux(m); 76 if (ip6a) { 77 /* XXX reject home-address option before rthdr */ 78 if (ip6a->ip6a_flags & IP6A_SWAP) { 79 V_ip6stat.ip6s_badoptions++; 80 m_freem(m); 81 return IPPROTO_DONE; 82 } 83 } 84 85 #ifndef PULLDOWN_TEST 86 IP6_EXTHDR_CHECK(m, off, sizeof(*rh), IPPROTO_DONE); 87 ip6 = mtod(m, struct ip6_hdr *); 88 rh = (struct ip6_rthdr *)((caddr_t)ip6 + off); 89 #else 90 ip6 = mtod(m, struct ip6_hdr *); 91 IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, sizeof(*rh)); 92 if (rh == NULL) { 93 V_ip6stat.ip6s_tooshort++; 94 return IPPROTO_DONE; 95 } 96 #endif 97 98 switch (rh->ip6r_type) { 99 #if 0 100 case IPV6_RTHDR_TYPE_0: 101 rhlen = (rh->ip6r_len + 1) << 3; 102 #ifndef PULLDOWN_TEST 103 /* 104 * note on option length: 105 * due to IP6_EXTHDR_CHECK assumption, we cannot handle 106 * very big routing header (max rhlen == 2048). 107 */ 108 IP6_EXTHDR_CHECK(m, off, rhlen, IPPROTO_DONE); 109 #else 110 /* 111 * note on option length: 112 * maximum rhlen: 2048 113 * max mbuf m_pulldown can handle: MCLBYTES == usually 2048 114 * so, here we are assuming that m_pulldown can handle 115 * rhlen == 2048 case. this may not be a good thing to 116 * assume - we may want to avoid pulling it up altogether. 117 */ 118 IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, rhlen); 119 if (rh == NULL) { 120 V_ip6stat.ip6s_tooshort++; 121 return IPPROTO_DONE; 122 } 123 #endif 124 if (ip6_rthdr0(m, ip6, (struct ip6_rthdr0 *)rh)) 125 return (IPPROTO_DONE); 126 break; 127 #endif /* Disable route header 0 */ 128 default: 129 /* unknown routing type */ 130 if (rh->ip6r_segleft == 0) { 131 rhlen = (rh->ip6r_len + 1) << 3; 132 break; /* Final dst. Just ignore the header. */ 133 } 134 V_ip6stat.ip6s_badoptions++; 135 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, 136 (caddr_t)&rh->ip6r_type - (caddr_t)ip6); 137 return (IPPROTO_DONE); 138 } 139 140 *offp += rhlen; 141 return (rh->ip6r_nxt); 142 } 143 144 /* 145 * Type0 routing header processing 146 * 147 * RFC2292 backward compatibility warning: no support for strict/loose bitmap, 148 * as it was dropped between RFC1883 and RFC2460. 149 */ 150 #if 0 151 static int 152 ip6_rthdr0(struct mbuf *m, struct ip6_hdr *ip6, struct ip6_rthdr0 *rh0) 153 { 154 INIT_VNET_INET6(curvnet); 155 int addrs, index; 156 struct in6_addr *nextaddr, tmpaddr; 157 struct in6_ifaddr *ifa; 158 159 if (rh0->ip6r0_segleft == 0) 160 return (0); 161 162 if (rh0->ip6r0_len % 2 163 #ifdef COMPAT_RFC1883 164 || rh0->ip6r0_len > 46 165 #endif 166 ) { 167 /* 168 * Type 0 routing header can't contain more than 23 addresses. 169 * RFC 2462: this limitation was removed since strict/loose 170 * bitmap field was deleted. 171 */ 172 V_ip6stat.ip6s_badoptions++; 173 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, 174 (caddr_t)&rh0->ip6r0_len - (caddr_t)ip6); 175 return (-1); 176 } 177 178 if ((addrs = rh0->ip6r0_len / 2) < rh0->ip6r0_segleft) { 179 V_ip6stat.ip6s_badoptions++; 180 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, 181 (caddr_t)&rh0->ip6r0_segleft - (caddr_t)ip6); 182 return (-1); 183 } 184 185 index = addrs - rh0->ip6r0_segleft; 186 rh0->ip6r0_segleft--; 187 nextaddr = ((struct in6_addr *)(rh0 + 1)) + index; 188 189 /* 190 * reject invalid addresses. be proactive about malicious use of 191 * IPv4 mapped/compat address. 192 * XXX need more checks? 193 */ 194 if (IN6_IS_ADDR_MULTICAST(nextaddr) || 195 IN6_IS_ADDR_UNSPECIFIED(nextaddr) || 196 IN6_IS_ADDR_V4MAPPED(nextaddr) || 197 IN6_IS_ADDR_V4COMPAT(nextaddr)) { 198 V_ip6stat.ip6s_badoptions++; 199 m_freem(m); 200 return (-1); 201 } 202 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 203 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst) || 204 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst) || 205 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 206 V_ip6stat.ip6s_badoptions++; 207 m_freem(m); 208 return (-1); 209 } 210 211 /* 212 * Determine the scope zone of the next hop, based on the interface 213 * of the current hop. [RFC4007, Section 9] 214 * Then disambiguate the scope zone for the next hop (if necessary). 215 */ 216 if ((ifa = ip6_getdstifaddr(m)) == NULL) 217 goto bad; 218 if (in6_setscope(nextaddr, ifa->ia_ifp, NULL) != 0) { 219 V_ip6stat.ip6s_badscope++; 220 goto bad; 221 } 222 223 /* 224 * Swap the IPv6 destination address and nextaddr. Forward the packet. 225 */ 226 tmpaddr = *nextaddr; 227 *nextaddr = ip6->ip6_dst; 228 in6_clearscope(nextaddr); /* XXX */ 229 ip6->ip6_dst = tmpaddr; 230 231 #ifdef COMPAT_RFC1883 232 if (rh0->ip6r0_slmap[index / 8] & (1 << (7 - (index % 8)))) 233 ip6_forward(m, IPV6_SRCRT_NEIGHBOR); 234 else 235 ip6_forward(m, IPV6_SRCRT_NOTNEIGHBOR); 236 #else 237 ip6_forward(m, 1); 238 #endif 239 240 return (-1); /* m would be freed in ip6_forward() */ 241 242 bad: 243 m_freem(m); 244 return (-1); 245 } 246 #endif 247