in6_gif.c revision 147256
11573Srgrimes/* $FreeBSD: head/sys/netinet6/in6_gif.c 147256 2005-06-10 16:49:24Z brooks $ */ 21573Srgrimes/* $KAME: in6_gif.c,v 1.49 2001/05/14 14:02:17 itojun Exp $ */ 31573Srgrimes 41573Srgrimes/*- 51573Srgrimes * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 61573Srgrimes * All rights reserved. 71573Srgrimes * 81573Srgrimes * Redistribution and use in source and binary forms, with or without 91573Srgrimes * modification, are permitted provided that the following conditions 101573Srgrimes * are met: 111573Srgrimes * 1. Redistributions of source code must retain the above copyright 121573Srgrimes * notice, this list of conditions and the following disclaimer. 131573Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 141573Srgrimes * notice, this list of conditions and the following disclaimer in the 151573Srgrimes * documentation and/or other materials provided with the distribution. 161573Srgrimes * 3. Neither the name of the project nor the names of its contributors 171573Srgrimes * may be used to endorse or promote products derived from this software 181573Srgrimes * without specific prior written permission. 191573Srgrimes * 201573Srgrimes * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 211573Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 221573Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 231573Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 241573Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 251573Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 261573Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 271573Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 281573Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 291573Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 301573Srgrimes * SUCH DAMAGE. 311573Srgrimes */ 321573Srgrimes 331573Srgrimes#include "opt_inet.h" 341573Srgrimes#include "opt_inet6.h" 351573Srgrimes 361573Srgrimes#include <sys/param.h> 371573Srgrimes#include <sys/systm.h> 381573Srgrimes#include <sys/socket.h> 391573Srgrimes#include <sys/sockio.h> 401573Srgrimes#include <sys/mbuf.h> 411573Srgrimes#include <sys/errno.h> 421573Srgrimes#include <sys/queue.h> 431573Srgrimes#include <sys/syslog.h> 441573Srgrimes#include <sys/protosw.h> 451573Srgrimes 461573Srgrimes#include <sys/malloc.h> 471573Srgrimes 481573Srgrimes#include <net/if.h> 491573Srgrimes#include <net/route.h> 501573Srgrimes 511573Srgrimes#include <netinet/in.h> 521573Srgrimes#include <netinet/in_systm.h> 531573Srgrimes#ifdef INET 541573Srgrimes#include <netinet/ip.h> 551573Srgrimes#endif 561573Srgrimes#include <netinet/ip_encap.h> 571573Srgrimes#ifdef INET6 581573Srgrimes#include <netinet/ip6.h> 591573Srgrimes#include <netinet6/ip6_var.h> 601573Srgrimes#include <netinet6/in6_gif.h> 611573Srgrimes#include <netinet6/in6_var.h> 621573Srgrimes#endif 631573Srgrimes#include <netinet6/ip6protosw.h> 641573Srgrimes#include <netinet/ip_ecn.h> 651573Srgrimes#ifdef INET6 661573Srgrimes#include <netinet6/ip6_ecn.h> 671573Srgrimes#endif 681573Srgrimes 691573Srgrimes#include <net/if_gif.h> 701573Srgrimes 711573Srgrimes#include <net/net_osdep.h> 721573Srgrimes 731573Srgrimesstatic int gif_validate6(const struct ip6_hdr *, struct gif_softc *, 741573Srgrimes struct ifnet *); 751573Srgrimes 761573Srgrimesextern struct domain inet6domain; 771573Srgrimesstruct ip6protosw in6_gif_protosw = 781573Srgrimes{ SOCK_RAW, &inet6domain, 0/* IPPROTO_IPV[46] */, PR_ATOMIC|PR_ADDR, 791573Srgrimes in6_gif_input, rip6_output, 0, rip6_ctloutput, 801573Srgrimes 0, 811573Srgrimes 0, 0, 0, 0, 821573Srgrimes &rip6_usrreqs 831573Srgrimes}; 841573Srgrimes 851573Srgrimesint 861573Srgrimesin6_gif_output(ifp, family, m) 871573Srgrimes struct ifnet *ifp; 881573Srgrimes int family; /* family of the packet to be encapsulate. */ 891573Srgrimes struct mbuf *m; 901573Srgrimes{ 911573Srgrimes struct gif_softc *sc = ifp->if_softc; 921573Srgrimes struct sockaddr_in6 *dst = (struct sockaddr_in6 *)&sc->gif_ro6.ro_dst; 931573Srgrimes struct sockaddr_in6 *sin6_src = (struct sockaddr_in6 *)sc->gif_psrc; 941573Srgrimes struct sockaddr_in6 *sin6_dst = (struct sockaddr_in6 *)sc->gif_pdst; 951573Srgrimes struct ip6_hdr *ip6; 961573Srgrimes int proto, error; 971573Srgrimes u_int8_t itos, otos; 981573Srgrimes 991573Srgrimes if (sin6_src == NULL || sin6_dst == NULL || 1001573Srgrimes sin6_src->sin6_family != AF_INET6 || 1011573Srgrimes sin6_dst->sin6_family != AF_INET6) { 1021573Srgrimes m_freem(m); 1031573Srgrimes return EAFNOSUPPORT; 1041573Srgrimes } 1051573Srgrimes 1061573Srgrimes switch (family) { 1071573Srgrimes#ifdef INET 1081573Srgrimes case AF_INET: 1091573Srgrimes { 1101573Srgrimes struct ip *ip; 1111573Srgrimes 1121573Srgrimes proto = IPPROTO_IPV4; 1131573Srgrimes if (m->m_len < sizeof(*ip)) { 1141573Srgrimes m = m_pullup(m, sizeof(*ip)); 1151573Srgrimes if (!m) 1161573Srgrimes return ENOBUFS; 1171573Srgrimes } 1181573Srgrimes ip = mtod(m, struct ip *); 1191573Srgrimes itos = ip->ip_tos; 1201573Srgrimes break; 1211573Srgrimes } 1221573Srgrimes#endif 1231573Srgrimes#ifdef INET6 1241573Srgrimes case AF_INET6: 1251573Srgrimes { 1261573Srgrimes struct ip6_hdr *ip6; 1271573Srgrimes proto = IPPROTO_IPV6; 1281573Srgrimes if (m->m_len < sizeof(*ip6)) { 1291573Srgrimes m = m_pullup(m, sizeof(*ip6)); 1301573Srgrimes if (!m) 1311573Srgrimes return ENOBUFS; 1321573Srgrimes } 1331573Srgrimes ip6 = mtod(m, struct ip6_hdr *); 1341573Srgrimes itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 1351573Srgrimes break; 1361573Srgrimes } 1371573Srgrimes#endif 1381573Srgrimes default: 1391573Srgrimes#ifdef DEBUG 1401573Srgrimes printf("in6_gif_output: warning: unknown family %d passed\n", 1411573Srgrimes family); 1421573Srgrimes#endif 1431573Srgrimes m_freem(m); 1441573Srgrimes return EAFNOSUPPORT; 1451573Srgrimes } 1461573Srgrimes 1471573Srgrimes /* prepend new IP header */ 1481573Srgrimes M_PREPEND(m, sizeof(struct ip6_hdr), M_DONTWAIT); 1491573Srgrimes if (m && m->m_len < sizeof(struct ip6_hdr)) 1501573Srgrimes m = m_pullup(m, sizeof(struct ip6_hdr)); 1511573Srgrimes if (m == NULL) { 1521573Srgrimes printf("ENOBUFS in in6_gif_output %d\n", __LINE__); 1531573Srgrimes return ENOBUFS; 1541573Srgrimes } 1551573Srgrimes 1561573Srgrimes ip6 = mtod(m, struct ip6_hdr *); 1571573Srgrimes ip6->ip6_flow = 0; 1581573Srgrimes ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 159 ip6->ip6_vfc |= IPV6_VERSION; 160 ip6->ip6_plen = htons((u_short)m->m_pkthdr.len); 161 ip6->ip6_nxt = proto; 162 ip6->ip6_hlim = ip6_gif_hlim; 163 ip6->ip6_src = sin6_src->sin6_addr; 164 /* bidirectional configured tunnel mode */ 165 if (!IN6_IS_ADDR_UNSPECIFIED(&sin6_dst->sin6_addr)) 166 ip6->ip6_dst = sin6_dst->sin6_addr; 167 else { 168 m_freem(m); 169 return ENETUNREACH; 170 } 171 ip_ecn_ingress((ifp->if_flags & IFF_LINK1) ? ECN_ALLOWED : ECN_NOCARE, 172 &otos, &itos); 173 ip6->ip6_flow &= ~htonl(0xff << 20); 174 ip6->ip6_flow |= htonl((u_int32_t)otos << 20); 175 176 if (dst->sin6_family != sin6_dst->sin6_family || 177 !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &sin6_dst->sin6_addr)) { 178 /* cache route doesn't match */ 179 bzero(dst, sizeof(*dst)); 180 dst->sin6_family = sin6_dst->sin6_family; 181 dst->sin6_len = sizeof(struct sockaddr_in6); 182 dst->sin6_addr = sin6_dst->sin6_addr; 183 if (sc->gif_ro6.ro_rt) { 184 RTFREE(sc->gif_ro6.ro_rt); 185 sc->gif_ro6.ro_rt = NULL; 186 } 187#if 0 188 GIF2IFP(sc)->if_mtu = GIF_MTU; 189#endif 190 } 191 192 if (sc->gif_ro6.ro_rt == NULL) { 193 rtalloc((struct route *)&sc->gif_ro6); 194 if (sc->gif_ro6.ro_rt == NULL) { 195 m_freem(m); 196 return ENETUNREACH; 197 } 198 199 /* if it constitutes infinite encapsulation, punt. */ 200 if (sc->gif_ro.ro_rt->rt_ifp == ifp) { 201 m_freem(m); 202 return ENETUNREACH; /*XXX*/ 203 } 204#if 0 205 ifp->if_mtu = sc->gif_ro6.ro_rt->rt_ifp->if_mtu 206 - sizeof(struct ip6_hdr); 207#endif 208 } 209 210#ifdef IPV6_MINMTU 211 /* 212 * force fragmentation to minimum MTU, to avoid path MTU discovery. 213 * it is too painful to ask for resend of inner packet, to achieve 214 * path MTU discovery for encapsulated packets. 215 */ 216 error = ip6_output(m, 0, &sc->gif_ro6, IPV6_MINMTU, 0, NULL, NULL); 217#else 218 error = ip6_output(m, 0, &sc->gif_ro6, 0, 0, NULL, NULL); 219#endif 220 221 if (!(GIF2IFP(sc)->if_flags & IFF_LINK0) && 222 sc->gif_ro6.ro_rt != NULL) { 223 RTFREE(sc->gif_ro6.ro_rt); 224 sc->gif_ro6.ro_rt = NULL; 225 } 226 227 return (error); 228} 229 230int 231in6_gif_input(mp, offp, proto) 232 struct mbuf **mp; 233 int *offp, proto; 234{ 235 struct mbuf *m = *mp; 236 struct ifnet *gifp = NULL; 237 struct ip6_hdr *ip6; 238 int af = 0; 239 u_int32_t otos; 240 241 ip6 = mtod(m, struct ip6_hdr *); 242 243 gifp = (struct ifnet *)encap_getarg(m); 244 245 if (gifp == NULL || (gifp->if_flags & IFF_UP) == 0) { 246 m_freem(m); 247 ip6stat.ip6s_nogif++; 248 return IPPROTO_DONE; 249 } 250 251 otos = ip6->ip6_flow; 252 m_adj(m, *offp); 253 254 switch (proto) { 255#ifdef INET 256 case IPPROTO_IPV4: 257 { 258 struct ip *ip; 259 u_int8_t otos8; 260 af = AF_INET; 261 otos8 = (ntohl(otos) >> 20) & 0xff; 262 if (m->m_len < sizeof(*ip)) { 263 m = m_pullup(m, sizeof(*ip)); 264 if (!m) 265 return IPPROTO_DONE; 266 } 267 ip = mtod(m, struct ip *); 268 if (ip_ecn_egress((gifp->if_flags & IFF_LINK1) ? 269 ECN_ALLOWED : ECN_NOCARE, 270 &otos8, &ip->ip_tos) == 0) { 271 m_freem(m); 272 return IPPROTO_DONE; 273 } 274 break; 275 } 276#endif /* INET */ 277#ifdef INET6 278 case IPPROTO_IPV6: 279 { 280 struct ip6_hdr *ip6; 281 af = AF_INET6; 282 if (m->m_len < sizeof(*ip6)) { 283 m = m_pullup(m, sizeof(*ip6)); 284 if (!m) 285 return IPPROTO_DONE; 286 } 287 ip6 = mtod(m, struct ip6_hdr *); 288 if (ip6_ecn_egress((gifp->if_flags & IFF_LINK1) ? 289 ECN_ALLOWED : ECN_NOCARE, 290 &otos, &ip6->ip6_flow) == 0) { 291 m_freem(m); 292 return IPPROTO_DONE; 293 } 294 break; 295 } 296#endif 297 default: 298 ip6stat.ip6s_nogif++; 299 m_freem(m); 300 return IPPROTO_DONE; 301 } 302 303 gif_input(m, af, gifp); 304 return IPPROTO_DONE; 305} 306 307/* 308 * validate outer address. 309 */ 310static int 311gif_validate6(ip6, sc, ifp) 312 const struct ip6_hdr *ip6; 313 struct gif_softc *sc; 314 struct ifnet *ifp; 315{ 316 struct sockaddr_in6 *src, *dst; 317 318 src = (struct sockaddr_in6 *)sc->gif_psrc; 319 dst = (struct sockaddr_in6 *)sc->gif_pdst; 320 321 /* 322 * Check for address match. Note that the check is for an incoming 323 * packet. We should compare the *source* address in our configuration 324 * and the *destination* address of the packet, and vice versa. 325 */ 326 if (!IN6_ARE_ADDR_EQUAL(&src->sin6_addr, &ip6->ip6_dst) || 327 !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &ip6->ip6_src)) 328 return 0; 329 330 /* martian filters on outer source - done in ip6_input */ 331 332 /* ingress filters on outer source */ 333 if ((GIF2IFP(sc)->if_flags & IFF_LINK2) == 0 && ifp) { 334 struct sockaddr_in6 sin6; 335 struct rtentry *rt; 336 337 bzero(&sin6, sizeof(sin6)); 338 sin6.sin6_family = AF_INET6; 339 sin6.sin6_len = sizeof(struct sockaddr_in6); 340 sin6.sin6_addr = ip6->ip6_src; 341 sin6.sin6_scope_id = 0; /* XXX */ 342 343 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 344 if (!rt || rt->rt_ifp != ifp) { 345#if 0 346 log(LOG_WARNING, "%s: packet from %s dropped " 347 "due to ingress filter\n", if_name(GIF2IFP(sc)), 348 ip6_sprintf(&sin6.sin6_addr)); 349#endif 350 if (rt) 351 rtfree(rt); 352 return 0; 353 } 354 rtfree(rt); 355 } 356 357 return 128 * 2; 358} 359 360/* 361 * we know that we are in IFF_UP, outer address available, and outer family 362 * matched the physical addr family. see gif_encapcheck(). 363 * sanity check for arg should have been done in the caller. 364 */ 365int 366gif_encapcheck6(m, off, proto, arg) 367 const struct mbuf *m; 368 int off; 369 int proto; 370 void *arg; 371{ 372 struct ip6_hdr ip6; 373 struct gif_softc *sc; 374 struct ifnet *ifp; 375 376 /* sanity check done in caller */ 377 sc = (struct gif_softc *)arg; 378 379 /* LINTED const cast */ 380 m_copydata(m, 0, sizeof(ip6), (caddr_t)&ip6); 381 ifp = ((m->m_flags & M_PKTHDR) != 0) ? m->m_pkthdr.rcvif : NULL; 382 383 return gif_validate6(&ip6, sc, ifp); 384} 385 386int 387in6_gif_attach(sc) 388 struct gif_softc *sc; 389{ 390 sc->encap_cookie6 = encap_attach_func(AF_INET6, -1, gif_encapcheck, 391 (struct protosw *)&in6_gif_protosw, sc); 392 if (sc->encap_cookie6 == NULL) 393 return EEXIST; 394 return 0; 395} 396 397int 398in6_gif_detach(sc) 399 struct gif_softc *sc; 400{ 401 int error; 402 403 error = encap_detach(sc->encap_cookie6); 404 if (error == 0) 405 sc->encap_cookie6 = NULL; 406 return error; 407} 408