1 /* $FreeBSD: src/sys/netinet6/in6_gif.c,v 1.2.2.7 2003/01/23 21:06:47 sam Exp $ */ 2 /* $DragonFly: src/sys/netinet6/in6_gif.c,v 1.11 2005/01/06 17:59:32 hsu Exp $ */ 3 /* $KAME: in6_gif.c,v 1.49 2001/05/14 14:02:17 itojun Exp $ */ 4 5 /* 6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include "opt_inet.h" 35 #include "opt_inet6.h" 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/socket.h> 40 #include <sys/sockio.h> 41 #include <sys/mbuf.h> 42 #include <sys/errno.h> 43 #include <sys/queue.h> 44 #include <sys/syslog.h> 45 #include <sys/protosw.h> 46 47 #include <sys/malloc.h> 48 49 #include <net/if.h> 50 #include <net/route.h> 51 52 #include <netinet/in.h> 53 #include <netinet/in_systm.h> 54 #ifdef INET 55 #include <netinet/ip.h> 56 #endif 57 #include <netinet/ip_encap.h> 58 #ifdef INET6 59 #include <netinet/ip6.h> 60 #include <netinet6/ip6_var.h> 61 #include <netinet6/in6_gif.h> 62 #include <netinet6/in6_var.h> 63 #endif 64 #include <netinet6/ip6protosw.h> 65 #include <netinet/ip_ecn.h> 66 #ifdef INET6 67 #include <netinet6/ip6_ecn.h> 68 #endif 69 70 #include <net/gif/if_gif.h> 71 72 #include <net/net_osdep.h> 73 74 static int gif_validate6(const struct ip6_hdr *, struct gif_softc *, 75 struct ifnet *); 76 77 extern struct domain inet6domain; 78 struct ip6protosw in6_gif_protosw = 79 { SOCK_RAW, &inet6domain, 0/*IPPROTO_IPV[46]*/, PR_ATOMIC|PR_ADDR, 80 in6_gif_input, rip6_output, 0, rip6_ctloutput, 81 cpu0_soport, 82 0, 0, 0, 0, 83 &rip6_usrreqs 84 }; 85 86 int 87 in6_gif_output(struct ifnet *ifp, 88 int family, /* family of the packet to be encapsulate. */ 89 struct mbuf *m) 90 { 91 struct gif_softc *sc = (struct gif_softc*)ifp; 92 struct sockaddr_in6 *dst = (struct sockaddr_in6 *)&sc->gif_ro6.ro_dst; 93 struct sockaddr_in6 *sin6_src = (struct sockaddr_in6 *)sc->gif_psrc; 94 struct sockaddr_in6 *sin6_dst = (struct sockaddr_in6 *)sc->gif_pdst; 95 struct ip6_hdr *ip6; 96 int proto; 97 u_int8_t itos, otos; 98 99 if (sin6_src == NULL || sin6_dst == NULL || 100 sin6_src->sin6_family != AF_INET6 || 101 sin6_dst->sin6_family != AF_INET6) { 102 m_freem(m); 103 return EAFNOSUPPORT; 104 } 105 106 switch (family) { 107 #ifdef INET 108 case AF_INET: 109 { 110 struct ip *ip; 111 112 proto = IPPROTO_IPV4; 113 if (m->m_len < sizeof(*ip)) { 114 m = m_pullup(m, sizeof(*ip)); 115 if (!m) 116 return ENOBUFS; 117 } 118 ip = mtod(m, struct ip *); 119 itos = ip->ip_tos; 120 break; 121 } 122 #endif 123 #ifdef INET6 124 case AF_INET6: 125 { 126 struct ip6_hdr *ip6; 127 proto = IPPROTO_IPV6; 128 if (m->m_len < sizeof(*ip6)) { 129 m = m_pullup(m, sizeof(*ip6)); 130 if (!m) 131 return ENOBUFS; 132 } 133 ip6 = mtod(m, struct ip6_hdr *); 134 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 135 break; 136 } 137 #endif 138 default: 139 #ifdef DEBUG 140 printf("in6_gif_output: warning: unknown family %d passed\n", 141 family); 142 #endif 143 m_freem(m); 144 return EAFNOSUPPORT; 145 } 146 147 /* prepend new IP header */ 148 M_PREPEND(m, sizeof(struct ip6_hdr), MB_DONTWAIT); 149 if (m && m->m_len < sizeof(struct ip6_hdr)) 150 m = m_pullup(m, sizeof(struct ip6_hdr)); 151 if (m == NULL) { 152 printf("ENOBUFS in in6_gif_output %d\n", __LINE__); 153 return ENOBUFS; 154 } 155 156 ip6 = mtod(m, struct ip6_hdr *); 157 ip6->ip6_flow = 0; 158 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 if (ifp->if_flags & IFF_LINK1) 172 ip_ecn_ingress(ECN_ALLOWED, &otos, &itos); 173 else 174 ip_ecn_ingress(ECN_NOCARE, &otos, &itos); 175 ip6->ip6_flow &= ~ntohl(0xff00000); 176 ip6->ip6_flow |= htonl((u_int32_t)otos << 20); 177 178 if (dst->sin6_family != sin6_dst->sin6_family || 179 !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &sin6_dst->sin6_addr)) { 180 /* cache route doesn't match */ 181 bzero(dst, sizeof(*dst)); 182 dst->sin6_family = sin6_dst->sin6_family; 183 dst->sin6_len = sizeof(struct sockaddr_in6); 184 dst->sin6_addr = sin6_dst->sin6_addr; 185 if (sc->gif_ro6.ro_rt) { 186 RTFREE(sc->gif_ro6.ro_rt); 187 sc->gif_ro6.ro_rt = NULL; 188 } 189 #if 0 190 sc->gif_if.if_mtu = GIF_MTU; 191 #endif 192 } 193 194 if (sc->gif_ro6.ro_rt == NULL) { 195 rtalloc((struct route *)&sc->gif_ro6); 196 if (sc->gif_ro6.ro_rt == NULL) { 197 m_freem(m); 198 return ENETUNREACH; 199 } 200 201 /* if it constitutes infinite encapsulation, punt. */ 202 if (sc->gif_ro.ro_rt->rt_ifp == ifp) { 203 m_freem(m); 204 return ENETUNREACH; /*XXX*/ 205 } 206 #if 0 207 ifp->if_mtu = sc->gif_ro6.ro_rt->rt_ifp->if_mtu 208 - sizeof(struct ip6_hdr); 209 #endif 210 } 211 212 #ifdef IPV6_MINMTU 213 /* 214 * force fragmentation to minimum MTU, to avoid path MTU discovery. 215 * it is too painful to ask for resend of inner packet, to achieve 216 * path MTU discovery for encapsulated packets. 217 */ 218 return(ip6_output(m, 0, &sc->gif_ro6, IPV6_MINMTU, 0, NULL, NULL)); 219 #else 220 return(ip6_output(m, 0, &sc->gif_ro6, 0, 0, NULL, NULL)); 221 #endif 222 } 223 224 int in6_gif_input(struct mbuf **mp, int *offp, int proto) 225 { 226 struct mbuf *m = *mp; 227 struct ifnet *gifp = NULL; 228 struct ip6_hdr *ip6; 229 int af = 0; 230 u_int32_t otos; 231 232 ip6 = mtod(m, struct ip6_hdr *); 233 234 gifp = (struct ifnet *)encap_getarg(m); 235 236 if (gifp == NULL || (gifp->if_flags & IFF_UP) == 0) { 237 m_freem(m); 238 ip6stat.ip6s_nogif++; 239 return IPPROTO_DONE; 240 } 241 242 otos = ip6->ip6_flow; 243 m_adj(m, *offp); 244 245 switch (proto) { 246 #ifdef INET 247 case IPPROTO_IPV4: 248 { 249 struct ip *ip; 250 u_int8_t otos8; 251 af = AF_INET; 252 otos8 = (ntohl(otos) >> 20) & 0xff; 253 if (m->m_len < sizeof(*ip)) { 254 m = m_pullup(m, sizeof(*ip)); 255 if (!m) 256 return IPPROTO_DONE; 257 } 258 ip = mtod(m, struct ip *); 259 if (gifp->if_flags & IFF_LINK1) 260 ip_ecn_egress(ECN_ALLOWED, &otos8, &ip->ip_tos); 261 else 262 ip_ecn_egress(ECN_NOCARE, &otos8, &ip->ip_tos); 263 break; 264 } 265 #endif /* INET */ 266 #ifdef INET6 267 case IPPROTO_IPV6: 268 { 269 struct ip6_hdr *ip6; 270 af = AF_INET6; 271 if (m->m_len < sizeof(*ip6)) { 272 m = m_pullup(m, sizeof(*ip6)); 273 if (!m) 274 return IPPROTO_DONE; 275 } 276 ip6 = mtod(m, struct ip6_hdr *); 277 if (gifp->if_flags & IFF_LINK1) 278 ip6_ecn_egress(ECN_ALLOWED, &otos, &ip6->ip6_flow); 279 else 280 ip6_ecn_egress(ECN_NOCARE, &otos, &ip6->ip6_flow); 281 break; 282 } 283 #endif 284 default: 285 ip6stat.ip6s_nogif++; 286 m_freem(m); 287 return IPPROTO_DONE; 288 } 289 290 gif_input(m, af, gifp); 291 return IPPROTO_DONE; 292 } 293 294 /* 295 * validate outer address. 296 */ 297 static int 298 gif_validate6(const struct ip6_hdr *ip6, struct gif_softc *sc, 299 struct ifnet *ifp) 300 { 301 struct sockaddr_in6 *src, *dst; 302 303 src = (struct sockaddr_in6 *)sc->gif_psrc; 304 dst = (struct sockaddr_in6 *)sc->gif_pdst; 305 306 /* 307 * Check for address match. Note that the check is for an incoming 308 * packet. We should compare the *source* address in our configuration 309 * and the *destination* address of the packet, and vice versa. 310 */ 311 if (!IN6_ARE_ADDR_EQUAL(&src->sin6_addr, &ip6->ip6_dst) || 312 !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &ip6->ip6_src)) 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 && ifp) { 319 struct sockaddr_in6 sin6; 320 struct rtentry *rt; 321 322 bzero(&sin6, sizeof(sin6)); 323 sin6.sin6_family = AF_INET6; 324 sin6.sin6_len = sizeof(struct sockaddr_in6); 325 sin6.sin6_addr = ip6->ip6_src; 326 #ifndef SCOPEDROUTING 327 sin6.sin6_scope_id = 0; /* XXX */ 328 #endif 329 330 rt = rtpurelookup((struct sockaddr *)&sin6); 331 if (rt == NULL || rt->rt_ifp != ifp) { 332 #if 0 333 log(LOG_WARNING, "%s: packet from %s dropped " 334 "due to ingress filter\n", if_name(&sc->gif_if), 335 ip6_sprintf(&sin6.sin6_addr)); 336 #endif 337 if (rt != NULL) 338 --rt->rt_refcnt; 339 return 0; 340 } 341 --rt->rt_refcnt; 342 } 343 344 return 128 * 2; 345 } 346 347 /* 348 * we know that we are in IFF_UP, outer address available, and outer family 349 * matched the physical addr family. see gif_encapcheck(). 350 * sanity check for arg should have been done in the caller. 351 */ 352 int 353 gif_encapcheck6(const struct mbuf *m, int off, int proto, void *arg) 354 { 355 struct ip6_hdr ip6; 356 struct gif_softc *sc; 357 struct ifnet *ifp; 358 359 /* sanity check done in caller */ 360 sc = (struct gif_softc *)arg; 361 362 m_copydata(m, 0, sizeof(ip6), (caddr_t)&ip6); 363 ifp = ((m->m_flags & M_PKTHDR) != 0) ? m->m_pkthdr.rcvif : NULL; 364 365 return gif_validate6(&ip6, sc, ifp); 366 } 367 368 int 369 in6_gif_attach(struct gif_softc *sc) 370 { 371 sc->encap_cookie6 = encap_attach_func(AF_INET6, -1, gif_encapcheck, 372 (struct protosw *)&in6_gif_protosw, sc); 373 if (sc->encap_cookie6 == NULL) 374 return EEXIST; 375 return 0; 376 } 377 378 int 379 in6_gif_detach(struct gif_softc *sc) 380 { 381 int error; 382 383 error = encap_detach(sc->encap_cookie6); 384 if (error == 0) 385 sc->encap_cookie6 = NULL; 386 return error; 387 } 388