1 /* $FreeBSD$ */ 2 /* $KAME: route6.c,v 1.24 2001/03/14 03:07:05 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 "opt_inet.h" 34 #include "opt_inet6.h" 35 36 #include <sys/param.h> 37 #include <sys/mbuf.h> 38 #include <sys/socket.h> 39 #include <sys/systm.h> 40 #include <sys/queue.h> 41 42 #include <net/if.h> 43 44 #include <netinet/in.h> 45 #include <netinet6/in6_var.h> 46 #include <netinet/ip6.h> 47 #include <netinet6/ip6_var.h> 48 #include <netinet6/scope6_var.h> 49 50 #include <netinet/icmp6.h> 51 52 #if 0 53 static int ip6_rthdr0 __P((struct mbuf *, struct ip6_hdr *, 54 struct ip6_rthdr0 *)); 55 56 #endif /* Disable route header processing. */ 57 58 int 59 route6_input(mp, offp, proto) 60 struct mbuf **mp; 61 int *offp, proto; /* proto is unused */ 62 { 63 struct ip6_hdr *ip6; 64 struct mbuf *m = *mp; 65 struct ip6_rthdr *rh; 66 int off = *offp, rhlen; 67 struct ip6aux *ip6a; 68 69 ip6a = ip6_findaux(m); 70 if (ip6a) { 71 /* XXX reject home-address option before rthdr */ 72 if (ip6a->ip6a_flags & IP6A_SWAP) { 73 ip6stat.ip6s_badoptions++; 74 m_freem(m); 75 return IPPROTO_DONE; 76 } 77 } 78 79 #ifndef PULLDOWN_TEST 80 IP6_EXTHDR_CHECK(m, off, sizeof(*rh), IPPROTO_DONE); 81 ip6 = mtod(m, struct ip6_hdr *); 82 rh = (struct ip6_rthdr *)((caddr_t)ip6 + off); 83 #else 84 ip6 = mtod(m, struct ip6_hdr *); 85 IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, sizeof(*rh)); 86 if (rh == NULL) { 87 ip6stat.ip6s_tooshort++; 88 return IPPROTO_DONE; 89 } 90 #endif 91 92 switch (rh->ip6r_type) { 93 #if 0 94 case IPV6_RTHDR_TYPE_0: 95 rhlen = (rh->ip6r_len + 1) << 3; 96 #ifndef PULLDOWN_TEST 97 /* 98 * note on option length: 99 * due to IP6_EXTHDR_CHECK assumption, we cannot handle 100 * very big routing header (max rhlen == 2048). 101 */ 102 IP6_EXTHDR_CHECK(m, off, rhlen, IPPROTO_DONE); 103 #else 104 /* 105 * note on option length: 106 * maximum rhlen: 2048 107 * max mbuf m_pulldown can handle: MCLBYTES == usually 2048 108 * so, here we are assuming that m_pulldown can handle 109 * rhlen == 2048 case. this may not be a good thing to 110 * assume - we may want to avoid pulling it up altogether. 111 */ 112 IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, rhlen); 113 if (rh == NULL) { 114 ip6stat.ip6s_tooshort++; 115 return IPPROTO_DONE; 116 } 117 #endif 118 if (ip6_rthdr0(m, ip6, (struct ip6_rthdr0 *)rh)) 119 return (IPPROTO_DONE); 120 break; 121 #endif /* Disable route header 0 */ 122 default: 123 /* unknown routing type */ 124 if (rh->ip6r_segleft == 0) { 125 rhlen = (rh->ip6r_len + 1) << 3; 126 break; /* Final dst. Just ignore the header. */ 127 } 128 ip6stat.ip6s_badoptions++; 129 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, 130 (caddr_t)&rh->ip6r_type - (caddr_t)ip6); 131 return (IPPROTO_DONE); 132 } 133 134 *offp += rhlen; 135 return (rh->ip6r_nxt); 136 } 137 138 /* 139 * Type0 routing header processing 140 * 141 * RFC2292 backward compatibility warning: no support for strict/loose bitmap, 142 * as it was dropped between RFC1883 and RFC2460. 143 */ 144 #if 0 145 static int 146 ip6_rthdr0(m, ip6, rh0) 147 struct mbuf *m; 148 struct ip6_hdr *ip6; 149 struct ip6_rthdr0 *rh0; 150 { 151 int addrs, index; 152 struct in6_addr *nextaddr, tmpaddr; 153 struct in6_ifaddr *ifa; 154 155 if (rh0->ip6r0_segleft == 0) 156 return (0); 157 158 if (rh0->ip6r0_len % 2 159 #ifdef COMPAT_RFC1883 160 || rh0->ip6r0_len > 46 161 #endif 162 ) { 163 /* 164 * Type 0 routing header can't contain more than 23 addresses. 165 * RFC 2462: this limitation was removed since strict/loose 166 * bitmap field was deleted. 167 */ 168 ip6stat.ip6s_badoptions++; 169 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, 170 (caddr_t)&rh0->ip6r0_len - (caddr_t)ip6); 171 return (-1); 172 } 173 174 if ((addrs = rh0->ip6r0_len / 2) < rh0->ip6r0_segleft) { 175 ip6stat.ip6s_badoptions++; 176 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, 177 (caddr_t)&rh0->ip6r0_segleft - (caddr_t)ip6); 178 return (-1); 179 } 180 181 index = addrs - rh0->ip6r0_segleft; 182 rh0->ip6r0_segleft--; 183 nextaddr = ((struct in6_addr *)(rh0 + 1)) + index; 184 185 /* 186 * reject invalid addresses. be proactive about malicious use of 187 * IPv4 mapped/compat address. 188 * XXX need more checks? 189 */ 190 if (IN6_IS_ADDR_MULTICAST(nextaddr) || 191 IN6_IS_ADDR_UNSPECIFIED(nextaddr) || 192 IN6_IS_ADDR_V4MAPPED(nextaddr) || 193 IN6_IS_ADDR_V4COMPAT(nextaddr)) { 194 ip6stat.ip6s_badoptions++; 195 m_freem(m); 196 return (-1); 197 } 198 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 199 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst) || 200 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst) || 201 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 202 ip6stat.ip6s_badoptions++; 203 m_freem(m); 204 return (-1); 205 } 206 207 /* 208 * Determine the scope zone of the next hop, based on the interface 209 * of the current hop. [RFC4007, Section 9] 210 * Then disambiguate the scope zone for the next hop (if necessary). 211 */ 212 if ((ifa = ip6_getdstifaddr(m)) == NULL) 213 goto bad; 214 if (in6_setscope(nextaddr, ifa->ia_ifp, NULL) != 0) { 215 ip6stat.ip6s_badscope++; 216 goto bad; 217 } 218 219 /* 220 * Swap the IPv6 destination address and nextaddr. Forward the packet. 221 */ 222 tmpaddr = *nextaddr; 223 *nextaddr = ip6->ip6_dst; 224 in6_clearscope(nextaddr); /* XXX */ 225 ip6->ip6_dst = tmpaddr; 226 227 #ifdef COMPAT_RFC1883 228 if (rh0->ip6r0_slmap[index / 8] & (1 << (7 - (index % 8)))) 229 ip6_forward(m, IPV6_SRCRT_NEIGHBOR); 230 else 231 ip6_forward(m, IPV6_SRCRT_NOTNEIGHBOR); 232 #else 233 ip6_forward(m, 1); 234 #endif 235 236 return (-1); /* m would be freed in ip6_forward() */ 237 238 bad: 239 m_freem(m); 240 return (-1); 241 } 242 #endif 243