1/* 2 * Copyright (c) 2009-2013 Apple Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. The rights granted to you under the License 10 * may not be used to create, or enable the creation or redistribution of, 11 * unlawful or unlicensed copies of an Apple operating system, or to 12 * circumvent, violate, or enable the circumvention or violation of, any 13 * terms of an Apple operating system software license agreement. 14 * 15 * Please obtain a copy of the License at 16 * http://www.opensource.apple.com/apsl/ and read it before using this file. 17 * 18 * The Original Code and all software distributed under the License are 19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23 * Please see the License for the specific language governing rights and 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27 */ 28 29/* $FreeBSD: src/sys/netinet6/in6_gif.c,v 1.2.2.3 2001/07/03 11:01:52 ume Exp $ */ 30/* $KAME: in6_gif.c,v 1.49 2001/05/14 14:02:17 itojun Exp $ */ 31 32/* 33 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 34 * All rights reserved. 35 * 36 * Redistribution and use in source and binary forms, with or without 37 * modification, are permitted provided that the following conditions 38 * are met: 39 * 1. Redistributions of source code must retain the above copyright 40 * notice, this list of conditions and the following disclaimer. 41 * 2. Redistributions in binary form must reproduce the above copyright 42 * notice, this list of conditions and the following disclaimer in the 43 * documentation and/or other materials provided with the distribution. 44 * 3. Neither the name of the project nor the names of its contributors 45 * may be used to endorse or promote products derived from this software 46 * without specific prior written permission. 47 * 48 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 51 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 58 * SUCH DAMAGE. 59 */ 60 61 62#include <sys/param.h> 63#include <sys/systm.h> 64#include <sys/socket.h> 65#include <sys/sockio.h> 66#include <sys/mbuf.h> 67#include <sys/errno.h> 68#include <sys/queue.h> 69#include <sys/syslog.h> 70 71#include <sys/malloc.h> 72#include <sys/protosw.h> 73 74#include <net/if.h> 75#include <net/route.h> 76 77#include <netinet/in.h> 78#include <netinet/in_systm.h> 79#if INET 80#include <netinet/ip.h> 81#endif 82#include <netinet/ip_encap.h> 83#if INET6 84#include <netinet/ip6.h> 85#include <netinet6/ip6_var.h> 86#include <netinet6/in6_gif.h> 87#include <netinet6/in6_var.h> 88#endif 89#include <netinet/ip_ecn.h> 90#if INET6 91#include <netinet6/ip6_ecn.h> 92#endif 93 94#include <net/if_gif.h> 95 96#include <net/net_osdep.h> 97 98int 99in6_gif_output( 100 struct ifnet *ifp, 101 int family, /* family of the packet to be encapsulate. */ 102 struct mbuf *m, 103 __unused struct rtentry *rt) 104{ 105 struct gif_softc *sc = ifnet_softc(ifp); 106 struct sockaddr_in6 *dst = (struct sockaddr_in6 *)&sc->gif_ro6.ro_dst; 107 struct sockaddr_in6 *sin6_src = (struct sockaddr_in6 *) 108 (void *)sc->gif_psrc; 109 struct sockaddr_in6 *sin6_dst = (struct sockaddr_in6 *) 110 (void *)sc->gif_pdst; 111 struct ip6_hdr *ip6; 112 int proto; 113 u_int8_t itos, otos; 114 115 GIF_LOCK_ASSERT(sc); 116 117 if (sin6_src == NULL || sin6_dst == NULL || 118 sin6_src->sin6_family != AF_INET6 || 119 sin6_dst->sin6_family != AF_INET6) { 120 m_freem(m); 121 return (EAFNOSUPPORT); 122 } 123 124 switch (family) { 125#if INET 126 case AF_INET: 127 { 128 struct ip *ip; 129 130 proto = IPPROTO_IPV4; 131 if (mbuf_len(m) < sizeof (*ip)) { 132 m = m_pullup(m, sizeof (*ip)); 133 if (!m) 134 return (ENOBUFS); 135 } 136 ip = mtod(m, struct ip *); 137 itos = ip->ip_tos; 138 break; 139 } 140#endif 141#if INET6 142 case AF_INET6: 143 { 144 proto = IPPROTO_IPV6; 145 if (mbuf_len(m) < sizeof (*ip6)) { 146 m = m_pullup(m, sizeof (*ip6)); 147 if (!m) 148 return (ENOBUFS); 149 } 150 ip6 = mtod(m, struct ip6_hdr *); 151 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 152 break; 153 } 154#endif 155 default: 156#if DEBUG 157 printf("in6_gif_output: warning: unknown family %d passed\n", 158 family); 159#endif 160 m_freem(m); 161 return (EAFNOSUPPORT); 162 } 163 164 /* prepend new IP header */ 165 M_PREPEND(m, sizeof (struct ip6_hdr), M_DONTWAIT); 166 if (m && mbuf_len(m) < sizeof (struct ip6_hdr)) 167 m = m_pullup(m, sizeof (struct ip6_hdr)); 168 if (m == NULL) { 169 printf("ENOBUFS in in6_gif_output %d\n", __LINE__); 170 return (ENOBUFS); 171 } 172 173 ip6 = mtod(m, struct ip6_hdr *); 174 ip6->ip6_flow = 0; 175 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 176 ip6->ip6_vfc |= IPV6_VERSION; 177 ip6->ip6_plen = htons((u_short)m->m_pkthdr.len); 178 ip6->ip6_nxt = proto; 179 ip6->ip6_hlim = ip6_gif_hlim; 180 ip6->ip6_src = sin6_src->sin6_addr; 181 /* bidirectional configured tunnel mode */ 182 if (!IN6_IS_ADDR_UNSPECIFIED(&sin6_dst->sin6_addr)) 183 ip6->ip6_dst = sin6_dst->sin6_addr; 184 else { 185 m_freem(m); 186 return (ENETUNREACH); 187 } 188 ip_ecn_ingress((ifp->if_flags & IFF_LINK1) ? ECN_ALLOWED : ECN_NOCARE, 189 &otos, &itos); 190 ip6->ip6_flow &= ~htonl(0xff << 20); 191 ip6->ip6_flow |= htonl((u_int32_t)otos << 20); 192 193 if (ROUTE_UNUSABLE(&sc->gif_ro6) || 194 dst->sin6_family != sin6_dst->sin6_family || 195 !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &sin6_dst->sin6_addr) || 196 (sc->gif_ro6.ro_rt != NULL && sc->gif_ro6.ro_rt->rt_ifp == ifp)) { 197 /* cache route doesn't match or recursive route */ 198 bzero(dst, sizeof (*dst)); 199 dst->sin6_family = sin6_dst->sin6_family; 200 dst->sin6_len = sizeof (struct sockaddr_in6); 201 dst->sin6_addr = sin6_dst->sin6_addr; 202 ROUTE_RELEASE(&sc->gif_ro6); 203#if 0 204 sc->gif_if.if_mtu = GIF_MTU; 205#endif 206 } 207 208 if (sc->gif_ro6.ro_rt == NULL) { 209 rtalloc((struct route *)&sc->gif_ro6); 210 if (sc->gif_ro6.ro_rt == NULL) { 211 m_freem(m); 212 return (ENETUNREACH); 213 } 214 RT_LOCK(sc->gif_ro6.ro_rt); 215 /* if it constitutes infinite encapsulation, punt. */ 216 if (sc->gif_ro6.ro_rt->rt_ifp == ifp) { 217 RT_UNLOCK(sc->gif_ro6.ro_rt); 218 m_freem(m); 219 return (ENETUNREACH); /* XXX */ 220 } 221#if 0 222 ifp->if_mtu = sc->gif_ro6.ro_rt->rt_ifp->if_mtu 223 - sizeof (struct ip6_hdr); 224#endif 225 RT_UNLOCK(sc->gif_ro6.ro_rt); 226 } 227 228#if IPV6_MINMTU 229 /* 230 * force fragmentation to minimum MTU, to avoid path MTU discovery. 231 * it is too painful to ask for resend of inner packet, to achieve 232 * path MTU discovery for encapsulated packets. 233 */ 234 return (ip6_output(m, 0, &sc->gif_ro6, IPV6_MINMTU, 0, NULL, NULL)); 235#else 236 return (ip6_output(m, 0, &sc->gif_ro6, 0, 0, NULL, NULL)); 237#endif 238} 239 240int 241in6_gif_input(struct mbuf **mp, int *offp, int proto) 242{ 243 struct mbuf *m = *mp; 244 struct ifnet *gifp = NULL; 245 struct ip6_hdr *ip6; 246 int af = 0; 247 u_int32_t otos; 248 249 ip6 = mtod(m, struct ip6_hdr *); 250 251 gifp = ((struct gif_softc *)encap_getarg(m))->gif_if; 252 253 if (gifp == NULL || (gifp->if_flags & IFF_UP) == 0) { 254 m_freem(m); 255 ip6stat.ip6s_nogif++; 256 return (IPPROTO_DONE); 257 } 258 259 otos = ip6->ip6_flow; 260 m_adj(m, *offp); 261 262 switch (proto) { 263#if INET 264 case IPPROTO_IPV4: 265 { 266 struct ip *ip; 267 u_int8_t otos8; 268 af = AF_INET; 269 otos8 = (ntohl(otos) >> 20) & 0xff; 270 if (mbuf_len(m) < sizeof (*ip)) { 271 m = m_pullup(m, sizeof (*ip)); 272 if (!m) 273 return (IPPROTO_DONE); 274 } 275 ip = mtod(m, struct ip *); 276 if (gifp->if_flags & IFF_LINK1) 277 ip_ecn_egress(ECN_ALLOWED, &otos8, &ip->ip_tos); 278 else 279 ip_ecn_egress(ECN_NOCARE, &otos8, &ip->ip_tos); 280 break; 281 } 282#endif /* INET */ 283#if INET6 284 case IPPROTO_IPV6: 285 { 286 af = AF_INET6; 287 if (mbuf_len(m) < sizeof (*ip6)) { 288 m = m_pullup(m, sizeof (*ip6)); 289 if (!m) 290 return (IPPROTO_DONE); 291 } 292 ip6 = mtod(m, struct ip6_hdr *); 293 if (gifp->if_flags & IFF_LINK1) 294 ip6_ecn_egress(ECN_ALLOWED, &otos, &ip6->ip6_flow); 295 else 296 ip6_ecn_egress(ECN_NOCARE, &otos, &ip6->ip6_flow); 297 break; 298 } 299#endif 300 default: 301 ip6stat.ip6s_nogif++; 302 m_freem(m); 303 return (IPPROTO_DONE); 304 } 305 306 /* Replace the rcvif by gifp for ifnet_input to route it correctly */ 307 if (m->m_pkthdr.rcvif) 308 m->m_pkthdr.rcvif = gifp; 309 310 ifnet_input(gifp, m, NULL); 311 return (IPPROTO_DONE); 312} 313 314/* 315 * validate outer address. 316 */ 317static int 318gif_validate6( 319 const struct ip6_hdr *ip6, 320 struct gif_softc *sc, 321 struct ifnet *ifp) 322{ 323 struct sockaddr_in6 *src, *dst; 324 325 src = (struct sockaddr_in6 *)(void *)sc->gif_psrc; 326 dst = (struct sockaddr_in6 *)(void *)sc->gif_pdst; 327 328 /* 329 * Check for address match. Note that the check is for an incoming 330 * packet. We should compare the *source* address in our configuration 331 * and the *destination* address of the packet, and vice versa. 332 */ 333 if (!IN6_ARE_ADDR_EQUAL(&src->sin6_addr, &ip6->ip6_dst) || 334 !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &ip6->ip6_src)) 335 return (0); 336 337 /* martian filters on outer source - done in ip6_input */ 338 339 /* ingress filters on outer source */ 340 if ((ifnet_flags(sc->gif_if) & IFF_LINK2) == 0 && ifp) { 341 struct sockaddr_in6 sin6; 342 struct rtentry *rt; 343 344 bzero(&sin6, sizeof (sin6)); 345 sin6.sin6_family = AF_INET6; 346 sin6.sin6_len = sizeof (struct sockaddr_in6); 347 sin6.sin6_addr = ip6->ip6_src; 348 349 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0); 350 if (rt != NULL) 351 RT_LOCK(rt); 352 if (!rt || rt->rt_ifp != ifp) { 353#if 0 354 log(LOG_WARNING, "%s: packet from %s dropped " 355 "due to ingress filter\n", if_name(&sc->gif_if), 356 ip6_sprintf(&sin6.sin6_addr)); 357#endif 358 if (rt != NULL) { 359 RT_UNLOCK(rt); 360 rtfree(rt); 361 } 362 return (0); 363 } 364 RT_UNLOCK(rt); 365 rtfree(rt); 366 } 367 368 return (128 * 2); 369} 370 371/* 372 * we know that we are in IFF_UP, outer address available, and outer family 373 * matched the physical addr family. see gif_encapcheck(). 374 * sanity check for arg should have been done in the caller. 375 */ 376int 377gif_encapcheck6( 378 const struct mbuf *m, 379 __unused int off, 380 __unused int proto, 381 void *arg) 382{ 383 struct ip6_hdr ip6; 384 struct gif_softc *sc; 385 struct ifnet *ifp; 386 387 /* sanity check done in caller */ 388 sc = (struct gif_softc *)arg; 389 390 GIF_LOCK_ASSERT(sc); 391 392 mbuf_copydata((struct mbuf *)(size_t)m, 0, sizeof (ip6), &ip6); 393 ifp = ((m->m_flags & M_PKTHDR) != 0) ? m->m_pkthdr.rcvif : NULL; 394 395 return (gif_validate6(&ip6, sc, ifp)); 396} 397