| 1 | /* $FreeBSD: src/sys/net/if_stf.c,v 1.1.2.11 2003/01/23 21:06:44 sam Exp $ */ |
| 2 | /* $DragonFly: src/sys/net/stf/if_stf.c,v 1.23 2008/06/08 08:38:05 sephe Exp $ */ |
| 3 | /* $KAME: if_stf.c,v 1.73 2001/12/03 11:08:30 keiichi Exp $ */ |
| 4 | |
| 5 | /* |
| 6 | * Copyright (C) 2000 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 | /* |
| 35 | * 6to4 interface, based on RFC3056. |
| 36 | * |
| 37 | * 6to4 interface is NOT capable of link-layer (I mean, IPv4) multicasting. |
| 38 | * There is no address mapping defined from IPv6 multicast address to IPv4 |
| 39 | * address. Therefore, we do not have IFF_MULTICAST on the interface. |
| 40 | * |
| 41 | * Due to the lack of address mapping for link-local addresses, we cannot |
| 42 | * throw packets toward link-local addresses (fe80::x). Also, we cannot throw |
| 43 | * packets to link-local multicast addresses (ff02::x). |
| 44 | * |
| 45 | * Here are interesting symptoms due to the lack of link-local address: |
| 46 | * |
| 47 | * Unicast routing exchange: |
| 48 | * - RIPng: Impossible. Uses link-local multicast packet toward ff02::9, |
| 49 | * and link-local addresses as nexthop. |
| 50 | * - OSPFv6: Impossible. OSPFv6 assumes that there's link-local address |
| 51 | * assigned to the link, and makes use of them. Also, HELLO packets use |
| 52 | * link-local multicast addresses (ff02::5 and ff02::6). |
| 53 | * - BGP4+: Maybe. You can only use global address as nexthop, and global |
| 54 | * address as TCP endpoint address. |
| 55 | * |
| 56 | * Multicast routing protocols: |
| 57 | * - PIM: Hello packet cannot be used to discover adjacent PIM routers. |
| 58 | * Adjacent PIM routers must be configured manually (is it really spec-wise |
| 59 | * correct thing to do?). |
| 60 | * |
| 61 | * ICMPv6: |
| 62 | * - Redirects cannot be used due to the lack of link-local address. |
| 63 | * |
| 64 | * stf interface does not have, and will not need, a link-local address. |
| 65 | * It seems to have no real benefit and does not help the above symptoms much. |
| 66 | * Even if we assign link-locals to interface, we cannot really |
| 67 | * use link-local unicast/multicast on top of 6to4 cloud (since there's no |
| 68 | * encapsulation defined for link-local address), and the above analysis does |
| 69 | * not change. RFC3056 does not mandate the assignment of link-local address |
| 70 | * either. |
| 71 | * |
| 72 | * 6to4 interface has security issues. Refer to |
| 73 | * http://playground.iijlab.net/i-d/draft-itojun-ipv6-transition-abuse-00.txt |
| 74 | * for details. The code tries to filter out some of malicious packets. |
| 75 | * Note that there is no way to be 100% secure. |
| 76 | */ |
| 77 | |
| 78 | #include "opt_inet.h" |
| 79 | #include "opt_inet6.h" |
| 80 | |
| 81 | #include <sys/param.h> |
| 82 | #include <sys/systm.h> |
| 83 | #include <sys/socket.h> |
| 84 | #include <sys/sockio.h> |
| 85 | #include <sys/mbuf.h> |
| 86 | #include <sys/errno.h> |
| 87 | #include <sys/protosw.h> |
| 88 | #include <sys/kernel.h> |
| 89 | #include <machine/cpu.h> |
| 90 | |
| 91 | #include <sys/malloc.h> |
| 92 | |
| 93 | #include <net/if.h> |
| 94 | #include <net/route.h> |
| 95 | #include <net/netisr.h> |
| 96 | #include <net/if_types.h> |
| 97 | #include "if_stf.h" |
| 98 | |
| 99 | #include <netinet/in.h> |
| 100 | #include <netinet/in_systm.h> |
| 101 | #include <netinet/ip.h> |
| 102 | #include <netinet/ip_var.h> |
| 103 | #include <netinet/in_var.h> |
| 104 | |
| 105 | #include <netinet/ip6.h> |
| 106 | #include <netinet6/ip6_var.h> |
| 107 | #include <netinet6/in6_var.h> |
| 108 | #include <netinet/ip_ecn.h> |
| 109 | |
| 110 | #include <netinet/ip_encap.h> |
| 111 | |
| 112 | #include <machine/stdarg.h> |
| 113 | |
| 114 | #include <net/net_osdep.h> |
| 115 | |
| 116 | #include <net/bpf.h> |
| 117 | |
| 118 | #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) |
| 119 | #define GET_V4(x) ((struct in_addr *)(&(x)->s6_addr16[1])) |
| 120 | |
| 121 | struct stf_softc { |
| 122 | struct ifnet sc_if; /* common area */ |
| 123 | union { |
| 124 | struct route __sc_ro4; |
| 125 | struct route_in6 __sc_ro6; /* just for safety */ |
| 126 | } __sc_ro46; |
| 127 | #define sc_ro __sc_ro46.__sc_ro4 |
| 128 | const struct encaptab *encap_cookie; |
| 129 | }; |
| 130 | |
| 131 | static struct stf_softc *stf; |
| 132 | |
| 133 | static MALLOC_DEFINE(M_STF, "stf", "6to4 Tunnel Interface"); |
| 134 | static int ip_stf_ttl = 40; |
| 135 | |
| 136 | extern struct domain inetdomain; |
| 137 | struct protosw in_stf_protosw = |
| 138 | { SOCK_RAW, &inetdomain, IPPROTO_IPV6, PR_ATOMIC|PR_ADDR, |
| 139 | in_stf_input, rip_output, 0, rip_ctloutput, |
| 140 | 0, |
| 141 | 0, 0, 0, 0, |
| 142 | &rip_usrreqs |
| 143 | }; |
| 144 | |
| 145 | static int stfmodevent (module_t, int, void *); |
| 146 | static int stf_encapcheck (const struct mbuf *, int, int, void *); |
| 147 | static struct in6_ifaddr *stf_getsrcifa6 (struct ifnet *); |
| 148 | static int stf_output (struct ifnet *, struct mbuf *, struct sockaddr *, |
| 149 | struct rtentry *); |
| 150 | static int stf_checkaddr4 (struct stf_softc *, struct in_addr *, |
| 151 | struct ifnet *); |
| 152 | static int stf_checkaddr6 (struct stf_softc *, struct in6_addr *, |
| 153 | struct ifnet *); |
| 154 | static void stf_rtrequest (int, struct rtentry *, struct rt_addrinfo *); |
| 155 | static int stf_ioctl (struct ifnet *, u_long, caddr_t, struct ucred *); |
| 156 | |
| 157 | static int |
| 158 | stfmodevent(module_t mod, int type, void *data) |
| 159 | { |
| 160 | struct stf_softc *sc; |
| 161 | int err; |
| 162 | const struct encaptab *p; |
| 163 | |
| 164 | switch (type) { |
| 165 | case MOD_LOAD: |
| 166 | stf = kmalloc(sizeof(struct stf_softc), M_STF, |
| 167 | M_WAITOK | M_ZERO); |
| 168 | sc = stf; |
| 169 | |
| 170 | bzero(sc, sizeof(*sc)); |
| 171 | if_initname(&(sc->sc_if), "stf", 0); |
| 172 | |
| 173 | p = encap_attach_func(AF_INET, IPPROTO_IPV6, stf_encapcheck, |
| 174 | (void *)&in_stf_protosw, sc); |
| 175 | if (p == NULL) { |
| 176 | kprintf("%s: attach failed\n", if_name(&sc->sc_if)); |
| 177 | return (ENOMEM); |
| 178 | } |
| 179 | sc->encap_cookie = p; |
| 180 | |
| 181 | sc->sc_if.if_mtu = IPV6_MMTU; |
| 182 | sc->sc_if.if_flags = 0; |
| 183 | sc->sc_if.if_ioctl = stf_ioctl; |
| 184 | sc->sc_if.if_output = stf_output; |
| 185 | sc->sc_if.if_type = IFT_STF; |
| 186 | #if 0 |
| 187 | /* turn off ingress filter */ |
| 188 | sc->sc_if.if_flags |= IFF_LINK2; |
| 189 | #endif |
| 190 | sc->sc_if.if_snd.ifq_maxlen = IFQ_MAXLEN; |
| 191 | if_attach(&sc->sc_if, NULL); |
| 192 | bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int)); |
| 193 | break; |
| 194 | case MOD_UNLOAD: |
| 195 | sc = stf; |
| 196 | bpfdetach(&sc->sc_if); |
| 197 | if_detach(&sc->sc_if); |
| 198 | err = encap_detach(sc->encap_cookie); |
| 199 | KASSERT(err == 0, ("Unexpected error detaching encap_cookie")); |
| 200 | kfree(sc, M_STF); |
| 201 | break; |
| 202 | } |
| 203 | |
| 204 | return (0); |
| 205 | } |
| 206 | |
| 207 | static moduledata_t stf_mod = { |
| 208 | "if_stf", |
| 209 | stfmodevent, |
| 210 | 0 |
| 211 | }; |
| 212 | |
| 213 | DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); |
| 214 | |
| 215 | static int |
| 216 | stf_encapcheck(const struct mbuf *m, int off, int proto, void *arg) |
| 217 | { |
| 218 | struct ip ip; |
| 219 | struct in6_ifaddr *ia6; |
| 220 | struct stf_softc *sc; |
| 221 | struct in_addr a, b; |
| 222 | |
| 223 | sc = (struct stf_softc *)arg; |
| 224 | if (sc == NULL) |
| 225 | return 0; |
| 226 | |
| 227 | if ((sc->sc_if.if_flags & IFF_UP) == 0) |
| 228 | return 0; |
| 229 | |
| 230 | /* IFF_LINK0 means "no decapsulation" */ |
| 231 | if ((sc->sc_if.if_flags & IFF_LINK0) != 0) |
| 232 | return 0; |
| 233 | |
| 234 | if (proto != IPPROTO_IPV6) |
| 235 | return 0; |
| 236 | |
| 237 | m_copydata(m, 0, sizeof(ip), (caddr_t)&ip); |
| 238 | |
| 239 | if (ip.ip_v != 4) |
| 240 | return 0; |
| 241 | |
| 242 | ia6 = stf_getsrcifa6(&sc->sc_if); |
| 243 | if (ia6 == NULL) |
| 244 | return 0; |
| 245 | |
| 246 | /* |
| 247 | * check if IPv4 dst matches the IPv4 address derived from the |
| 248 | * local 6to4 address. |
| 249 | * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... |
| 250 | */ |
| 251 | if (bcmp(GET_V4(&ia6->ia_addr.sin6_addr), &ip.ip_dst, |
| 252 | sizeof(ip.ip_dst)) != 0) |
| 253 | return 0; |
| 254 | |
| 255 | /* |
| 256 | * check if IPv4 src matches the IPv4 address derived from the |
| 257 | * local 6to4 address masked by prefixmask. |
| 258 | * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 |
| 259 | * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 |
| 260 | */ |
| 261 | bzero(&a, sizeof(a)); |
| 262 | a.s_addr = GET_V4(&ia6->ia_addr.sin6_addr)->s_addr; |
| 263 | a.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr; |
| 264 | b = ip.ip_src; |
| 265 | b.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr; |
| 266 | if (a.s_addr != b.s_addr) |
| 267 | return 0; |
| 268 | |
| 269 | /* stf interface makes single side match only */ |
| 270 | return 32; |
| 271 | } |
| 272 | |
| 273 | static struct in6_ifaddr * |
| 274 | stf_getsrcifa6(struct ifnet *ifp) |
| 275 | { |
| 276 | struct ifaddr_container *ifac; |
| 277 | struct in_ifaddr *ia4; |
| 278 | struct sockaddr_in6 *sin6; |
| 279 | struct in_addr in; |
| 280 | |
| 281 | TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) { |
| 282 | struct ifaddr *ia = ifac->ifa; |
| 283 | |
| 284 | if (ia->ifa_addr == NULL) |
| 285 | continue; |
| 286 | if (ia->ifa_addr->sa_family != AF_INET6) |
| 287 | continue; |
| 288 | sin6 = (struct sockaddr_in6 *)ia->ifa_addr; |
| 289 | if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) |
| 290 | continue; |
| 291 | |
| 292 | bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); |
| 293 | LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) |
| 294 | if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) |
| 295 | break; |
| 296 | if (ia4 == NULL) |
| 297 | continue; |
| 298 | |
| 299 | return (struct in6_ifaddr *)ia; |
| 300 | } |
| 301 | |
| 302 | return NULL; |
| 303 | } |
| 304 | |
| 305 | static int |
| 306 | stf_output_serialized(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, |
| 307 | struct rtentry *rt) |
| 308 | { |
| 309 | struct stf_softc *sc; |
| 310 | struct sockaddr_in6 *dst6; |
| 311 | struct in_addr *in4; |
| 312 | struct sockaddr_in *dst4; |
| 313 | u_int8_t tos; |
| 314 | struct ip *ip; |
| 315 | struct ip6_hdr *ip6; |
| 316 | struct in6_ifaddr *ia6; |
| 317 | static const uint32_t af = AF_INET6; |
| 318 | |
| 319 | sc = (struct stf_softc*)ifp; |
| 320 | dst6 = (struct sockaddr_in6 *)dst; |
| 321 | |
| 322 | /* just in case */ |
| 323 | if ((ifp->if_flags & IFF_UP) == 0) { |
| 324 | m_freem(m); |
| 325 | return ENETDOWN; |
| 326 | } |
| 327 | |
| 328 | /* |
| 329 | * If we don't have an ip4 address that match my inner ip6 address, |
| 330 | * we shouldn't generate output. Without this check, we'll end up |
| 331 | * using wrong IPv4 source. |
| 332 | */ |
| 333 | ia6 = stf_getsrcifa6(ifp); |
| 334 | if (ia6 == NULL) { |
| 335 | m_freem(m); |
| 336 | return ENETDOWN; |
| 337 | } |
| 338 | |
| 339 | if (m->m_len < sizeof(*ip6)) { |
| 340 | m = m_pullup(m, sizeof(*ip6)); |
| 341 | if (!m) |
| 342 | return ENOBUFS; |
| 343 | } |
| 344 | ip6 = mtod(m, struct ip6_hdr *); |
| 345 | tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; |
| 346 | |
| 347 | /* |
| 348 | * Pickup the right outer dst addr from the list of candidates. |
| 349 | * ip6_dst has priority as it may be able to give us shorter IPv4 hops. |
| 350 | */ |
| 351 | if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) |
| 352 | in4 = GET_V4(&ip6->ip6_dst); |
| 353 | else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) |
| 354 | in4 = GET_V4(&dst6->sin6_addr); |
| 355 | else { |
| 356 | m_freem(m); |
| 357 | return ENETUNREACH; |
| 358 | } |
| 359 | |
| 360 | if (ifp->if_bpf) |
| 361 | bpf_ptap(ifp->if_bpf, m, &af, sizeof(af)); |
| 362 | |
| 363 | M_PREPEND(m, sizeof(struct ip), MB_DONTWAIT); |
| 364 | if (m && m->m_len < sizeof(struct ip)) |
| 365 | m = m_pullup(m, sizeof(struct ip)); |
| 366 | if (m == NULL) |
| 367 | return ENOBUFS; |
| 368 | ip = mtod(m, struct ip *); |
| 369 | |
| 370 | bzero(ip, sizeof(*ip)); |
| 371 | |
| 372 | bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr), |
| 373 | &ip->ip_src, sizeof(ip->ip_src)); |
| 374 | bcopy(in4, &ip->ip_dst, sizeof(ip->ip_dst)); |
| 375 | ip->ip_p = IPPROTO_IPV6; |
| 376 | ip->ip_ttl = ip_stf_ttl; |
| 377 | ip->ip_len = m->m_pkthdr.len; /*host order*/ |
| 378 | if (ifp->if_flags & IFF_LINK1) |
| 379 | ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); |
| 380 | else |
| 381 | ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); |
| 382 | |
| 383 | dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst; |
| 384 | if (dst4->sin_family != AF_INET || |
| 385 | bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) { |
| 386 | /* cache route doesn't match */ |
| 387 | dst4->sin_family = AF_INET; |
| 388 | dst4->sin_len = sizeof(struct sockaddr_in); |
| 389 | bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr)); |
| 390 | if (sc->sc_ro.ro_rt) { |
| 391 | RTFREE(sc->sc_ro.ro_rt); |
| 392 | sc->sc_ro.ro_rt = NULL; |
| 393 | } |
| 394 | } |
| 395 | |
| 396 | if (sc->sc_ro.ro_rt == NULL) { |
| 397 | rtalloc(&sc->sc_ro); |
| 398 | if (sc->sc_ro.ro_rt == NULL) { |
| 399 | m_freem(m); |
| 400 | return ENETUNREACH; |
| 401 | } |
| 402 | } |
| 403 | |
| 404 | return ip_output(m, NULL, &sc->sc_ro, 0, NULL, NULL); |
| 405 | } |
| 406 | |
| 407 | static int |
| 408 | stf_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, |
| 409 | struct rtentry *rt) |
| 410 | { |
| 411 | int error; |
| 412 | |
| 413 | lwkt_serialize_enter(ifp->if_serializer); |
| 414 | error = stf_output_serialized(ifp, m, dst, rt); |
| 415 | lwkt_serialize_exit(ifp->if_serializer); |
| 416 | |
| 417 | return error; |
| 418 | } |
| 419 | |
| 420 | /* |
| 421 | * Parameters: |
| 422 | * inifp: incoming interface |
| 423 | */ |
| 424 | static int |
| 425 | stf_checkaddr4(struct stf_softc *sc, struct in_addr *in, struct ifnet *inifp) |
| 426 | { |
| 427 | struct in_ifaddr_container *iac; |
| 428 | |
| 429 | /* |
| 430 | * reject packets with the following address: |
| 431 | * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 |
| 432 | */ |
| 433 | if (IN_MULTICAST(ntohl(in->s_addr))) |
| 434 | return -1; |
| 435 | switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { |
| 436 | case 0: case 127: case 255: |
| 437 | return -1; |
| 438 | } |
| 439 | |
| 440 | /* |
| 441 | * reject packets with broadcast |
| 442 | */ |
| 443 | TAILQ_FOREACH(iac, &in_ifaddrheads[mycpuid], ia_link) { |
| 444 | struct in_ifaddr *ia4 = iac->ia; |
| 445 | |
| 446 | if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) |
| 447 | continue; |
| 448 | if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) |
| 449 | return -1; |
| 450 | } |
| 451 | |
| 452 | /* |
| 453 | * perform ingress filter |
| 454 | */ |
| 455 | if (sc && (sc->sc_if.if_flags & IFF_LINK2) == 0 && inifp) { |
| 456 | struct sockaddr_in sin; |
| 457 | struct rtentry *rt; |
| 458 | |
| 459 | bzero(&sin, sizeof(sin)); |
| 460 | sin.sin_family = AF_INET; |
| 461 | sin.sin_len = sizeof(struct sockaddr_in); |
| 462 | sin.sin_addr = *in; |
| 463 | rt = rtpurelookup((struct sockaddr *)&sin); |
| 464 | if (!rt || rt->rt_ifp != inifp) { |
| 465 | #if 0 |
| 466 | log(LOG_WARNING, "%s: packet from 0x%x dropped " |
| 467 | "due to ingress filter\n", if_name(&sc->sc_if), |
| 468 | (u_int32_t)ntohl(sin.sin_addr.s_addr)); |
| 469 | #endif |
| 470 | if (rt) |
| 471 | rtfree(rt); |
| 472 | return -1; |
| 473 | } |
| 474 | rtfree(rt); |
| 475 | } |
| 476 | |
| 477 | return 0; |
| 478 | } |
| 479 | |
| 480 | /* |
| 481 | * Parameters: |
| 482 | * inifp: incoming interface |
| 483 | */ |
| 484 | static int |
| 485 | stf_checkaddr6(struct stf_softc *sc, struct in6_addr *in6, struct ifnet *inifp) |
| 486 | { |
| 487 | /* |
| 488 | * check 6to4 addresses |
| 489 | */ |
| 490 | if (IN6_IS_ADDR_6TO4(in6)) |
| 491 | return stf_checkaddr4(sc, GET_V4(in6), inifp); |
| 492 | |
| 493 | /* |
| 494 | * reject anything that look suspicious. the test is implemented |
| 495 | * in ip6_input too, but we check here as well to |
| 496 | * (1) reject bad packets earlier, and |
| 497 | * (2) to be safe against future ip6_input change. |
| 498 | */ |
| 499 | if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) |
| 500 | return -1; |
| 501 | |
| 502 | return 0; |
| 503 | } |
| 504 | |
| 505 | void |
| 506 | in_stf_input(struct mbuf *m, ...) |
| 507 | { |
| 508 | struct stf_softc *sc; |
| 509 | struct ip *ip; |
| 510 | struct ip6_hdr *ip6; |
| 511 | u_int8_t otos, itos; |
| 512 | struct ifnet *ifp; |
| 513 | int off, proto; |
| 514 | static const uint32_t af = AF_INET6; |
| 515 | __va_list ap; |
| 516 | |
| 517 | __va_start(ap, m); |
| 518 | off = __va_arg(ap, int); |
| 519 | proto = __va_arg(ap, int); |
| 520 | __va_end(ap); |
| 521 | |
| 522 | if (proto != IPPROTO_IPV6) { |
| 523 | m_freem(m); |
| 524 | return; |
| 525 | } |
| 526 | |
| 527 | ip = mtod(m, struct ip *); |
| 528 | |
| 529 | sc = (struct stf_softc *)encap_getarg(m); |
| 530 | |
| 531 | if (sc == NULL || (sc->sc_if.if_flags & IFF_UP) == 0) { |
| 532 | m_freem(m); |
| 533 | return; |
| 534 | } |
| 535 | |
| 536 | ifp = &sc->sc_if; |
| 537 | |
| 538 | /* |
| 539 | * perform sanity check against outer src/dst. |
| 540 | * for source, perform ingress filter as well. |
| 541 | */ |
| 542 | if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || |
| 543 | stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { |
| 544 | m_freem(m); |
| 545 | return; |
| 546 | } |
| 547 | |
| 548 | otos = ip->ip_tos; |
| 549 | m_adj(m, off); |
| 550 | |
| 551 | if (m->m_len < sizeof(*ip6)) { |
| 552 | m = m_pullup(m, sizeof(*ip6)); |
| 553 | if (!m) |
| 554 | return; |
| 555 | } |
| 556 | ip6 = mtod(m, struct ip6_hdr *); |
| 557 | |
| 558 | /* |
| 559 | * perform sanity check against inner src/dst. |
| 560 | * for source, perform ingress filter as well. |
| 561 | */ |
| 562 | if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || |
| 563 | stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { |
| 564 | m_freem(m); |
| 565 | return; |
| 566 | } |
| 567 | |
| 568 | itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; |
| 569 | if ((ifp->if_flags & IFF_LINK1) != 0) |
| 570 | ip_ecn_egress(ECN_ALLOWED, &otos, &itos); |
| 571 | else |
| 572 | ip_ecn_egress(ECN_NOCARE, &otos, &itos); |
| 573 | ip6->ip6_flow &= ~htonl(0xff << 20); |
| 574 | ip6->ip6_flow |= htonl((u_int32_t)itos << 20); |
| 575 | |
| 576 | m->m_pkthdr.rcvif = ifp; |
| 577 | |
| 578 | if (ifp->if_bpf) |
| 579 | bpf_ptap(ifp->if_bpf, m, &af, sizeof(af)); |
| 580 | |
| 581 | /* |
| 582 | * Put the packet to the network layer input queue according to the |
| 583 | * specified address family. |
| 584 | * See net/if_gif.c for possible issues with packet processing |
| 585 | * reorder due to extra queueing. |
| 586 | */ |
| 587 | ifp->if_ipackets++; |
| 588 | ifp->if_ibytes += m->m_pkthdr.len; |
| 589 | netisr_dispatch(NETISR_IPV6, m); |
| 590 | } |
| 591 | |
| 592 | /* ARGSUSED */ |
| 593 | static void |
| 594 | stf_rtrequest(int cmd, struct rtentry *rt, struct rt_addrinfo *info) |
| 595 | { |
| 596 | |
| 597 | if (rt) |
| 598 | rt->rt_rmx.rmx_mtu = IPV6_MMTU; |
| 599 | } |
| 600 | |
| 601 | static int |
| 602 | stf_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data, struct ucred *cr) |
| 603 | { |
| 604 | struct ifaddr *ifa; |
| 605 | struct ifreq *ifr; |
| 606 | struct sockaddr_in6 *sin6; |
| 607 | int error; |
| 608 | |
| 609 | error = 0; |
| 610 | switch (cmd) { |
| 611 | case SIOCSIFADDR: |
| 612 | ifa = (struct ifaddr *)data; |
| 613 | if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { |
| 614 | error = EAFNOSUPPORT; |
| 615 | break; |
| 616 | } |
| 617 | sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; |
| 618 | if (IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { |
| 619 | ifa->ifa_rtrequest = stf_rtrequest; |
| 620 | ifp->if_flags |= IFF_UP; |
| 621 | } else |
| 622 | error = EINVAL; |
| 623 | break; |
| 624 | |
| 625 | case SIOCADDMULTI: |
| 626 | case SIOCDELMULTI: |
| 627 | ifr = (struct ifreq *)data; |
| 628 | if (ifr && ifr->ifr_addr.sa_family == AF_INET6) |
| 629 | ; |
| 630 | else |
| 631 | error = EAFNOSUPPORT; |
| 632 | break; |
| 633 | |
| 634 | default: |
| 635 | error = EINVAL; |
| 636 | break; |
| 637 | } |
| 638 | |
| 639 | return error; |
| 640 | } |