1 /* $FreeBSD$ */ 2 /* $KAME: in6_gif.c,v 1.49 2001/05/14 14:02:17 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/systm.h> 38 #include <sys/socket.h> 39 #include <sys/sockio.h> 40 #include <sys/mbuf.h> 41 #include <sys/errno.h> 42 #include <sys/queue.h> 43 #include <sys/syslog.h> 44 45 #include <sys/malloc.h> 46 47 #include <net/if.h> 48 #include <net/route.h> 49 50 #include <netinet/in.h> 51 #include <netinet/in_systm.h> 52 #ifdef INET 53 #include <netinet/ip.h> 54 #endif 55 #include <netinet/ip_encap.h> 56 #ifdef INET6 57 #include <netinet/ip6.h> 58 #include <netinet6/ip6_var.h> 59 #include <netinet6/in6_gif.h> 60 #include <netinet6/in6_var.h> 61 #endif 62 #include <netinet/ip_ecn.h> 63 #ifdef INET6 64 #include <netinet6/ip6_ecn.h> 65 #endif 66 67 #include <net/if_gif.h> 68 69 #include <net/net_osdep.h> 70 71 int 72 in6_gif_output(ifp, family, m, rt) 73 struct ifnet *ifp; 74 int family; /* family of the packet to be encapsulate. */ 75 struct mbuf *m; 76 struct rtentry *rt; 77 { 78 struct gif_softc *sc = (struct gif_softc*)ifp; 79 struct sockaddr_in6 *dst = (struct sockaddr_in6 *)&sc->gif_ro6.ro_dst; 80 struct sockaddr_in6 *sin6_src = (struct sockaddr_in6 *)sc->gif_psrc; 81 struct sockaddr_in6 *sin6_dst = (struct sockaddr_in6 *)sc->gif_pdst; 82 struct ip6_hdr *ip6; 83 int proto; 84 u_int8_t itos, otos; 85 86 if (sin6_src == NULL || sin6_dst == NULL || 87 sin6_src->sin6_family != AF_INET6 || 88 sin6_dst->sin6_family != AF_INET6) { 89 m_freem(m); 90 return EAFNOSUPPORT; 91 } 92 93 switch (family) { 94 #ifdef INET 95 case AF_INET: 96 { 97 struct ip *ip; 98 99 proto = IPPROTO_IPV4; 100 if (m->m_len < sizeof(*ip)) { 101 m = m_pullup(m, sizeof(*ip)); 102 if (!m) 103 return ENOBUFS; 104 } 105 ip = mtod(m, struct ip *); 106 itos = ip->ip_tos; 107 break; 108 } 109 #endif 110 #ifdef INET6 111 case AF_INET6: 112 { 113 struct ip6_hdr *ip6; 114 proto = IPPROTO_IPV6; 115 if (m->m_len < sizeof(*ip6)) { 116 m = m_pullup(m, sizeof(*ip6)); 117 if (!m) 118 return ENOBUFS; 119 } 120 ip6 = mtod(m, struct ip6_hdr *); 121 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 122 break; 123 } 124 #endif 125 default: 126 #ifdef DEBUG 127 printf("in6_gif_output: warning: unknown family %d passed\n", 128 family); 129 #endif 130 m_freem(m); 131 return EAFNOSUPPORT; 132 } 133 134 /* prepend new IP header */ 135 M_PREPEND(m, sizeof(struct ip6_hdr), M_DONTWAIT); 136 if (m && m->m_len < sizeof(struct ip6_hdr)) 137 m = m_pullup(m, sizeof(struct ip6_hdr)); 138 if (m == NULL) { 139 printf("ENOBUFS in in6_gif_output %d\n", __LINE__); 140 return ENOBUFS; 141 } 142 143 ip6 = mtod(m, struct ip6_hdr *); 144 ip6->ip6_flow = 0; 145 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 146 ip6->ip6_vfc |= IPV6_VERSION; 147 ip6->ip6_plen = htons((u_short)m->m_pkthdr.len); 148 ip6->ip6_nxt = proto; 149 ip6->ip6_hlim = ip6_gif_hlim; 150 ip6->ip6_src = sin6_src->sin6_addr; 151 /* bidirectional configured tunnel mode */ 152 if (!IN6_IS_ADDR_UNSPECIFIED(&sin6_dst->sin6_addr)) 153 ip6->ip6_dst = sin6_dst->sin6_addr; 154 else { 155 m_freem(m); 156 return ENETUNREACH; 157 } 158 if (ifp->if_flags & IFF_LINK1) 159 ip_ecn_ingress(ECN_ALLOWED, &otos, &itos); 160 else 161 ip_ecn_ingress(ECN_NOCARE, &otos, &itos); 162 ip6->ip6_flow &= ~ntohl(0xff00000); 163 ip6->ip6_flow |= htonl((u_int32_t)otos << 20); 164 165 if (dst->sin6_family != sin6_dst->sin6_family || 166 !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &sin6_dst->sin6_addr)) { 167 /* cache route doesn't match */ 168 bzero(dst, sizeof(*dst)); 169 dst->sin6_family = sin6_dst->sin6_family; 170 dst->sin6_len = sizeof(struct sockaddr_in6); 171 dst->sin6_addr = sin6_dst->sin6_addr; 172 if (sc->gif_ro6.ro_rt) { 173 RTFREE(sc->gif_ro6.ro_rt); 174 sc->gif_ro6.ro_rt = NULL; 175 } 176 #if 0 177 sc->gif_if.if_mtu = GIF_MTU; 178 #endif 179 } 180 181 if (sc->gif_ro6.ro_rt == NULL) { 182 rtalloc((struct route *)&sc->gif_ro6); 183 if (sc->gif_ro6.ro_rt == NULL) { 184 m_freem(m); 185 return ENETUNREACH; 186 } 187 188 /* if it constitutes infinite encapsulation, punt. */ 189 if (sc->gif_ro.ro_rt->rt_ifp == ifp) { 190 m_freem(m); 191 return ENETUNREACH; /*XXX*/ 192 } 193 #if 0 194 ifp->if_mtu = sc->gif_ro6.ro_rt->rt_ifp->if_mtu 195 - sizeof(struct ip6_hdr); 196 #endif 197 } 198 199 #ifdef IPV6_MINMTU 200 /* 201 * force fragmentation to minimum MTU, to avoid path MTU discovery. 202 * it is too painful to ask for resend of inner packet, to achieve 203 * path MTU discovery for encapsulated packets. 204 */ 205 return(ip6_output(m, 0, &sc->gif_ro6, IPV6_MINMTU, 0, NULL)); 206 #else 207 return(ip6_output(m, 0, &sc->gif_ro6, 0, 0, NULL)); 208 #endif 209 } 210 211 int in6_gif_input(mp, offp, proto) 212 struct mbuf **mp; 213 int *offp, proto; 214 { 215 struct mbuf *m = *mp; 216 struct ifnet *gifp = NULL; 217 struct ip6_hdr *ip6; 218 int af = 0; 219 u_int32_t otos; 220 221 ip6 = mtod(m, struct ip6_hdr *); 222 223 gifp = (struct ifnet *)encap_getarg(m); 224 225 if (gifp == NULL || (gifp->if_flags & IFF_UP) == 0) { 226 m_freem(m); 227 ip6stat.ip6s_nogif++; 228 return IPPROTO_DONE; 229 } 230 231 otos = ip6->ip6_flow; 232 m_adj(m, *offp); 233 234 switch (proto) { 235 #ifdef INET 236 case IPPROTO_IPV4: 237 { 238 struct ip *ip; 239 u_int8_t otos8; 240 af = AF_INET; 241 otos8 = (ntohl(otos) >> 20) & 0xff; 242 if (m->m_len < sizeof(*ip)) { 243 m = m_pullup(m, sizeof(*ip)); 244 if (!m) 245 return IPPROTO_DONE; 246 } 247 ip = mtod(m, struct ip *); 248 if (gifp->if_flags & IFF_LINK1) 249 ip_ecn_egress(ECN_ALLOWED, &otos8, &ip->ip_tos); 250 else 251 ip_ecn_egress(ECN_NOCARE, &otos8, &ip->ip_tos); 252 break; 253 } 254 #endif /* INET */ 255 #ifdef INET6 256 case IPPROTO_IPV6: 257 { 258 struct ip6_hdr *ip6; 259 af = AF_INET6; 260 if (m->m_len < sizeof(*ip6)) { 261 m = m_pullup(m, sizeof(*ip6)); 262 if (!m) 263 return IPPROTO_DONE; 264 } 265 ip6 = mtod(m, struct ip6_hdr *); 266 if (gifp->if_flags & IFF_LINK1) 267 ip6_ecn_egress(ECN_ALLOWED, &otos, &ip6->ip6_flow); 268 else 269 ip6_ecn_egress(ECN_NOCARE, &otos, &ip6->ip6_flow); 270 break; 271 } 272 #endif 273 default: 274 ip6stat.ip6s_nogif++; 275 m_freem(m); 276 return IPPROTO_DONE; 277 } 278 279 gif_input(m, af, gifp); 280 return IPPROTO_DONE; 281 } 282 283 /* 284 * we know that we are in IFF_UP, outer address available, and outer family 285 * matched the physical addr family. see gif_encapcheck(). 286 */ 287 int 288 gif_encapcheck6(m, off, proto, arg) 289 const struct mbuf *m; 290 int off; 291 int proto; 292 void *arg; 293 { 294 struct ip6_hdr ip6; 295 struct gif_softc *sc; 296 struct sockaddr_in6 *src, *dst; 297 int addrmatch; 298 299 /* sanity check done in caller */ 300 sc = (struct gif_softc *)arg; 301 src = (struct sockaddr_in6 *)sc->gif_psrc; 302 dst = (struct sockaddr_in6 *)sc->gif_pdst; 303 304 m_copydata(m, 0, sizeof(ip6), (caddr_t)&ip6); 305 306 /* check for address match */ 307 addrmatch = 0; 308 if (IN6_ARE_ADDR_EQUAL(&src->sin6_addr, &ip6.ip6_dst)) 309 addrmatch |= 1; 310 if (IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &ip6.ip6_src)) 311 addrmatch |= 2; 312 if (addrmatch != 3) 313 return 0; 314 315 /* martian filters on outer source - done in ip6_input */ 316 317 /* ingress filters on outer source */ 318 if ((sc->gif_if.if_flags & IFF_LINK2) == 0 && 319 (m->m_flags & M_PKTHDR) != 0 && m->m_pkthdr.rcvif) { 320 struct sockaddr_in6 sin6; 321 struct rtentry *rt; 322 323 bzero(&sin6, sizeof(sin6)); 324 sin6.sin6_family = AF_INET6; 325 sin6.sin6_len = sizeof(struct sockaddr_in6); 326 sin6.sin6_addr = ip6.ip6_src; 327 /* XXX scopeid */ 328 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 329 if (!rt || rt->rt_ifp != m->m_pkthdr.rcvif) { 330 #if 0 331 log(LOG_WARNING, "%s: packet from %s dropped " 332 "due to ingress filter\n", if_name(&sc->gif_if), 333 ip6_sprintf(&sin6.sin6_addr)); 334 #endif 335 if (rt) 336 rtfree(rt); 337 return 0; 338 } 339 rtfree(rt); 340 } 341 342 return 128 * 2; 343 } 344