1/* 2 * Copyright (c) 2009-2012 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 98static __inline__ void* 99_cast_non_const(const void * ptr) { 100 union { 101 const void* cval; 102 void* val; 103 } ret; 104 105 ret.cval = ptr; 106 return (ret.val); 107} 108 109int 110in6_gif_output( 111 struct ifnet *ifp, 112 int family, /* family of the packet to be encapsulate. */ 113 struct mbuf *m, 114 __unused struct rtentry *rt) 115{ 116 struct gif_softc *sc = ifnet_softc(ifp); 117 struct sockaddr_in6 *dst = (struct sockaddr_in6 *)&sc->gif_ro6.ro_dst; 118 struct sockaddr_in6 *sin6_src = (struct sockaddr_in6 *)(void *)sc->gif_psrc; 119 struct sockaddr_in6 *sin6_dst = (struct sockaddr_in6 *)(void *)sc->gif_pdst; 120 struct ip6_hdr *ip6; 121 int proto; 122 u_int8_t itos, otos; 123 124 if (sin6_src == NULL || sin6_dst == NULL || 125 sin6_src->sin6_family != AF_INET6 || 126 sin6_dst->sin6_family != AF_INET6) { 127 m_freem(m); 128 return EAFNOSUPPORT; 129 } 130 131 switch (family) { 132#if INET 133 case AF_INET: 134 { 135 struct ip *ip; 136 137 proto = IPPROTO_IPV4; 138 if (mbuf_len(m) < sizeof(*ip)) { 139 m = m_pullup(m, sizeof(*ip)); 140 if (!m) 141 return ENOBUFS; 142 } 143 ip = mtod(m, struct ip *); 144 itos = ip->ip_tos; 145 break; 146 } 147#endif 148#if INET6 149 case AF_INET6: 150 { 151 proto = IPPROTO_IPV6; 152 if (mbuf_len(m) < sizeof(*ip6)) { 153 m = m_pullup(m, sizeof(*ip6)); 154 if (!m) 155 return ENOBUFS; 156 } 157 ip6 = mtod(m, struct ip6_hdr *); 158 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 159 break; 160 } 161#endif 162 default: 163#if DEBUG 164 printf("in6_gif_output: warning: unknown family %d passed\n", 165 family); 166#endif 167 m_freem(m); 168 return EAFNOSUPPORT; 169 } 170 171 /* prepend new IP header */ 172 M_PREPEND(m, sizeof(struct ip6_hdr), M_DONTWAIT); 173 if (m && mbuf_len(m) < sizeof(struct ip6_hdr)) 174 m = m_pullup(m, sizeof(struct ip6_hdr)); 175 if (m == NULL) { 176 printf("ENOBUFS in in6_gif_output %d\n", __LINE__); 177 return ENOBUFS; 178 } 179 180 ip6 = mtod(m, struct ip6_hdr *); 181 ip6->ip6_flow = 0; 182 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 183 ip6->ip6_vfc |= IPV6_VERSION; 184 ip6->ip6_plen = htons((u_short)m->m_pkthdr.len); 185 ip6->ip6_nxt = proto; 186 ip6->ip6_hlim = ip6_gif_hlim; 187 ip6->ip6_src = sin6_src->sin6_addr; 188 /* bidirectional configured tunnel mode */ 189 if (!IN6_IS_ADDR_UNSPECIFIED(&sin6_dst->sin6_addr)) 190 ip6->ip6_dst = sin6_dst->sin6_addr; 191 else { 192 m_freem(m); 193 return ENETUNREACH; 194 } 195 ip_ecn_ingress((ifp->if_flags & IFF_LINK1) ? ECN_ALLOWED : ECN_NOCARE, 196 &otos, &itos); 197 ip6->ip6_flow &= ~htonl(0xff << 20); 198 ip6->ip6_flow |= htonl((u_int32_t)otos << 20); 199 200 if (dst->sin6_family != sin6_dst->sin6_family || 201 !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &sin6_dst->sin6_addr) || 202 (sc->gif_ro6.ro_rt != NULL && 203 (sc->gif_ro6.ro_rt->generation_id != route_generation || 204 sc->gif_ro6.ro_rt->rt_ifp == ifp))) { 205 /* cache route doesn't match or recursive route */ 206 bzero(dst, sizeof(*dst)); 207 dst->sin6_family = sin6_dst->sin6_family; 208 dst->sin6_len = sizeof(struct sockaddr_in6); 209 dst->sin6_addr = sin6_dst->sin6_addr; 210 if (sc->gif_ro6.ro_rt) { 211 rtfree(sc->gif_ro6.ro_rt); 212 sc->gif_ro6.ro_rt = NULL; 213 } 214#if 0 215 sc->gif_if.if_mtu = GIF_MTU; 216#endif 217 } 218 219 if (sc->gif_ro6.ro_rt == NULL) { 220 rtalloc((struct route *)&sc->gif_ro6); 221 if (sc->gif_ro6.ro_rt == NULL) { 222 m_freem(m); 223 return ENETUNREACH; 224 } 225 RT_LOCK(sc->gif_ro6.ro_rt); 226 /* if it constitutes infinite encapsulation, punt. */ 227 if (sc->gif_ro6.ro_rt->rt_ifp == ifp) { 228 RT_UNLOCK(sc->gif_ro6.ro_rt); 229 m_freem(m); 230 return ENETUNREACH; /*XXX*/ 231 } 232#if 0 233 ifp->if_mtu = sc->gif_ro6.ro_rt->rt_ifp->if_mtu 234 - sizeof(struct ip6_hdr); 235#endif 236 RT_UNLOCK(sc->gif_ro6.ro_rt); 237 } 238 239#if IPV6_MINMTU 240 /* 241 * force fragmentation to minimum MTU, to avoid path MTU discovery. 242 * it is too painful to ask for resend of inner packet, to achieve 243 * path MTU discovery for encapsulated packets. 244 */ 245 return(ip6_output(m, 0, &sc->gif_ro6, IPV6_MINMTU, 0, NULL, NULL)); 246#else 247 return(ip6_output(m, 0, &sc->gif_ro6, 0, 0, NULL, NULL)); 248#endif 249} 250 251int in6_gif_input(struct mbuf **mp, int *offp, int proto) 252{ 253 struct mbuf *m = *mp; 254 struct ifnet *gifp = NULL; 255 struct ip6_hdr *ip6; 256 int af = 0; 257 u_int32_t otos; 258 259 ip6 = mtod(m, struct ip6_hdr *); 260 261 gifp = ((struct gif_softc*)encap_getarg(m))->gif_if; 262 263 if (gifp == NULL || (gifp->if_flags & IFF_UP) == 0) { 264 m_freem(m); 265 ip6stat.ip6s_nogif++; 266 return IPPROTO_DONE; 267 } 268 269 otos = ip6->ip6_flow; 270 m_adj(m, *offp); 271 272 switch (proto) { 273#if INET 274 case IPPROTO_IPV4: 275 { 276 struct ip *ip; 277 u_int8_t otos8; 278 af = AF_INET; 279 otos8 = (ntohl(otos) >> 20) & 0xff; 280 if (mbuf_len(m) < sizeof(*ip)) { 281 m = m_pullup(m, sizeof(*ip)); 282 if (!m) 283 return IPPROTO_DONE; 284 } 285 ip = mtod(m, struct ip *); 286 if (gifp->if_flags & IFF_LINK1) 287 ip_ecn_egress(ECN_ALLOWED, &otos8, &ip->ip_tos); 288 else 289 ip_ecn_egress(ECN_NOCARE, &otos8, &ip->ip_tos); 290 break; 291 } 292#endif /* INET */ 293#if INET6 294 case IPPROTO_IPV6: 295 { 296 af = AF_INET6; 297 if (mbuf_len(m) < sizeof(*ip6)) { 298 m = m_pullup(m, sizeof(*ip6)); 299 if (!m) 300 return IPPROTO_DONE; 301 } 302 ip6 = mtod(m, struct ip6_hdr *); 303 if (gifp->if_flags & IFF_LINK1) 304 ip6_ecn_egress(ECN_ALLOWED, &otos, &ip6->ip6_flow); 305 else 306 ip6_ecn_egress(ECN_NOCARE, &otos, &ip6->ip6_flow); 307 break; 308 } 309#endif 310 default: 311 ip6stat.ip6s_nogif++; 312 m_freem(m); 313 return IPPROTO_DONE; 314 } 315 316 if (m->m_pkthdr.rcvif) /* replace the rcvif by gifp for ifnet_input to route it correctly */ 317 m->m_pkthdr.rcvif = gifp; 318 319 ifnet_input(gifp, m, NULL); 320 return IPPROTO_DONE; 321} 322 323/* 324 * validate outer address. 325 */ 326static int 327gif_validate6( 328 const struct ip6_hdr *ip6, 329 struct gif_softc *sc, 330 struct ifnet *ifp) 331{ 332 struct sockaddr_in6 *src, *dst; 333 334 src = (struct sockaddr_in6 *)(void *)sc->gif_psrc; 335 dst = (struct sockaddr_in6 *)(void *)sc->gif_pdst; 336 337 /* 338 * Check for address match. Note that the check is for an incoming 339 * packet. We should compare the *source* address in our configuration 340 * and the *destination* address of the packet, and vice versa. 341 */ 342 if (!IN6_ARE_ADDR_EQUAL(&src->sin6_addr, &ip6->ip6_dst) || 343 !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &ip6->ip6_src)) 344 return 0; 345 346 /* martian filters on outer source - done in ip6_input */ 347 348 /* ingress filters on outer source */ 349 if ((ifnet_flags(sc->gif_if) & IFF_LINK2) == 0 && ifp) { 350 struct sockaddr_in6 sin6; 351 struct rtentry *rt; 352 353 bzero(&sin6, sizeof(sin6)); 354 sin6.sin6_family = AF_INET6; 355 sin6.sin6_len = sizeof(struct sockaddr_in6); 356 sin6.sin6_addr = ip6->ip6_src; 357 358 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0); 359 if (rt != NULL) 360 RT_LOCK(rt); 361 if (!rt || rt->rt_ifp != ifp) { 362#if 0 363 log(LOG_WARNING, "%s: packet from %s dropped " 364 "due to ingress filter\n", if_name(&sc->gif_if), 365 ip6_sprintf(&sin6.sin6_addr)); 366#endif 367 if (rt != NULL) { 368 RT_UNLOCK(rt); 369 rtfree(rt); 370 } 371 return 0; 372 } 373 RT_UNLOCK(rt); 374 rtfree(rt); 375 } 376 377 return 128 * 2; 378} 379 380/* 381 * we know that we are in IFF_UP, outer address available, and outer family 382 * matched the physical addr family. see gif_encapcheck(). 383 * sanity check for arg should have been done in the caller. 384 */ 385int 386gif_encapcheck6( 387 const struct mbuf *m, 388 __unused int off, 389 __unused int proto, 390 void *arg) 391{ 392 struct ip6_hdr ip6; 393 struct gif_softc *sc; 394 struct ifnet *ifp; 395 396 /* sanity check done in caller */ 397 sc = (struct gif_softc *)arg; 398 399 mbuf_copydata((struct mbuf *)(size_t)m, 0, sizeof(ip6), &ip6); 400 ifp = ((m->m_flags & M_PKTHDR) != 0) ? m->m_pkthdr.rcvif : NULL; 401 402 return gif_validate6(&ip6, sc, ifp); 403} 404