1 /*- 2 * Copyright (c) 2014, 2018 Andrey V. Elsukov <ae@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <sys/param.h> 31 #include <sys/systm.h> 32 #include <sys/jail.h> 33 #include <sys/kernel.h> 34 #include <sys/lock.h> 35 #include <sys/malloc.h> 36 #include <sys/module.h> 37 #include <sys/mbuf.h> 38 #include <sys/priv.h> 39 #include <sys/proc.h> 40 #include <sys/socket.h> 41 #include <sys/sockio.h> 42 #include <sys/sx.h> 43 #include <sys/sysctl.h> 44 #include <sys/syslog.h> 45 46 #include <net/bpf.h> 47 #include <net/ethernet.h> 48 #include <net/if.h> 49 #include <net/if_var.h> 50 #include <net/if_private.h> 51 #include <net/if_clone.h> 52 #include <net/if_types.h> 53 #include <net/netisr.h> 54 #include <net/vnet.h> 55 #include <net/route.h> 56 57 #include <netinet/in.h> 58 #include <netinet/in_systm.h> 59 #include <netinet/in_var.h> 60 #include <netinet/ip.h> 61 #include <netinet/ip_var.h> 62 #include <netinet/ip_encap.h> 63 64 #include <machine/in_cksum.h> 65 #include <security/mac/mac_framework.h> 66 67 #define MEMTU (1500 - sizeof(struct mobhdr)) 68 static const char mename[] = "me"; 69 static MALLOC_DEFINE(M_IFME, mename, "Minimal Encapsulation for IP"); 70 /* Minimal forwarding header RFC 2004 */ 71 struct mobhdr { 72 uint8_t mob_proto; /* protocol */ 73 uint8_t mob_flags; /* flags */ 74 #define MOB_FLAGS_SP 0x80 /* source present */ 75 uint16_t mob_csum; /* header checksum */ 76 struct in_addr mob_dst; /* original destination address */ 77 struct in_addr mob_src; /* original source addr (optional) */ 78 } __packed; 79 80 struct me_softc { 81 struct ifnet *me_ifp; 82 u_int me_fibnum; 83 struct in_addr me_src; 84 struct in_addr me_dst; 85 86 CK_LIST_ENTRY(me_softc) chain; 87 CK_LIST_ENTRY(me_softc) srchash; 88 }; 89 CK_LIST_HEAD(me_list, me_softc); 90 #define ME2IFP(sc) ((sc)->me_ifp) 91 #define ME_READY(sc) ((sc)->me_src.s_addr != 0) 92 #define ME_RLOCK_TRACKER struct epoch_tracker me_et 93 #define ME_RLOCK() epoch_enter_preempt(net_epoch_preempt, &me_et) 94 #define ME_RUNLOCK() epoch_exit_preempt(net_epoch_preempt, &me_et) 95 #define ME_WAIT() epoch_wait_preempt(net_epoch_preempt) 96 97 #ifndef ME_HASH_SIZE 98 #define ME_HASH_SIZE (1 << 4) 99 #endif 100 VNET_DEFINE_STATIC(struct me_list *, me_hashtbl) = NULL; 101 VNET_DEFINE_STATIC(struct me_list *, me_srchashtbl) = NULL; 102 #define V_me_hashtbl VNET(me_hashtbl) 103 #define V_me_srchashtbl VNET(me_srchashtbl) 104 #define ME_HASH(src, dst) (V_me_hashtbl[\ 105 me_hashval((src), (dst)) & (ME_HASH_SIZE - 1)]) 106 #define ME_SRCHASH(src) (V_me_srchashtbl[\ 107 fnv_32_buf(&(src), sizeof(src), FNV1_32_INIT) & (ME_HASH_SIZE - 1)]) 108 109 static struct sx me_ioctl_sx; 110 SX_SYSINIT(me_ioctl_sx, &me_ioctl_sx, "me_ioctl"); 111 112 static int me_clone_create(struct if_clone *, int, caddr_t); 113 static void me_clone_destroy(struct ifnet *); 114 VNET_DEFINE_STATIC(struct if_clone *, me_cloner); 115 #define V_me_cloner VNET(me_cloner) 116 117 #ifdef VIMAGE 118 static void me_reassign(struct ifnet *, struct vnet *, char *); 119 #endif 120 static void me_qflush(struct ifnet *); 121 static int me_transmit(struct ifnet *, struct mbuf *); 122 static int me_ioctl(struct ifnet *, u_long, caddr_t); 123 static int me_output(struct ifnet *, struct mbuf *, 124 const struct sockaddr *, struct route *); 125 static int me_input(struct mbuf *, int, int, void *); 126 127 static int me_set_tunnel(struct me_softc *, in_addr_t, in_addr_t); 128 static void me_delete_tunnel(struct me_softc *); 129 130 SYSCTL_DECL(_net_link); 131 static SYSCTL_NODE(_net_link, IFT_TUNNEL, me, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 132 "Minimal Encapsulation for IP (RFC 2004)"); 133 #ifndef MAX_ME_NEST 134 #define MAX_ME_NEST 1 135 #endif 136 137 VNET_DEFINE_STATIC(int, max_me_nesting) = MAX_ME_NEST; 138 #define V_max_me_nesting VNET(max_me_nesting) 139 SYSCTL_INT(_net_link_me, OID_AUTO, max_nesting, CTLFLAG_RW | CTLFLAG_VNET, 140 &VNET_NAME(max_me_nesting), 0, "Max nested tunnels"); 141 142 static uint32_t 143 me_hashval(in_addr_t src, in_addr_t dst) 144 { 145 uint32_t ret; 146 147 ret = fnv_32_buf(&src, sizeof(src), FNV1_32_INIT); 148 return (fnv_32_buf(&dst, sizeof(dst), ret)); 149 } 150 151 static struct me_list * 152 me_hashinit(void) 153 { 154 struct me_list *hash; 155 int i; 156 157 hash = malloc(sizeof(struct me_list) * ME_HASH_SIZE, 158 M_IFME, M_WAITOK); 159 for (i = 0; i < ME_HASH_SIZE; i++) 160 CK_LIST_INIT(&hash[i]); 161 162 return (hash); 163 } 164 165 static void 166 vnet_me_init(const void *unused __unused) 167 { 168 169 V_me_cloner = if_clone_simple(mename, me_clone_create, 170 me_clone_destroy, 0); 171 } 172 VNET_SYSINIT(vnet_me_init, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY, 173 vnet_me_init, NULL); 174 175 static void 176 vnet_me_uninit(const void *unused __unused) 177 { 178 179 if (V_me_hashtbl != NULL) { 180 free(V_me_hashtbl, M_IFME); 181 V_me_hashtbl = NULL; 182 ME_WAIT(); 183 free(V_me_srchashtbl, M_IFME); 184 } 185 if_clone_detach(V_me_cloner); 186 } 187 VNET_SYSUNINIT(vnet_me_uninit, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY, 188 vnet_me_uninit, NULL); 189 190 static int 191 me_clone_create(struct if_clone *ifc, int unit, caddr_t params) 192 { 193 struct me_softc *sc; 194 195 sc = malloc(sizeof(struct me_softc), M_IFME, M_WAITOK | M_ZERO); 196 sc->me_fibnum = curthread->td_proc->p_fibnum; 197 ME2IFP(sc) = if_alloc(IFT_TUNNEL); 198 ME2IFP(sc)->if_softc = sc; 199 if_initname(ME2IFP(sc), mename, unit); 200 201 ME2IFP(sc)->if_mtu = MEMTU; 202 ME2IFP(sc)->if_flags = IFF_POINTOPOINT|IFF_MULTICAST; 203 ME2IFP(sc)->if_output = me_output; 204 ME2IFP(sc)->if_ioctl = me_ioctl; 205 ME2IFP(sc)->if_transmit = me_transmit; 206 ME2IFP(sc)->if_qflush = me_qflush; 207 #ifdef VIMAGE 208 ME2IFP(sc)->if_reassign = me_reassign; 209 #endif 210 ME2IFP(sc)->if_capabilities |= IFCAP_LINKSTATE; 211 ME2IFP(sc)->if_capenable |= IFCAP_LINKSTATE; 212 if_attach(ME2IFP(sc)); 213 bpfattach(ME2IFP(sc), DLT_NULL, sizeof(u_int32_t)); 214 return (0); 215 } 216 217 #ifdef VIMAGE 218 static void 219 me_reassign(struct ifnet *ifp, struct vnet *new_vnet __unused, 220 char *unused __unused) 221 { 222 struct me_softc *sc; 223 224 sx_xlock(&me_ioctl_sx); 225 sc = ifp->if_softc; 226 if (sc != NULL) 227 me_delete_tunnel(sc); 228 sx_xunlock(&me_ioctl_sx); 229 } 230 #endif /* VIMAGE */ 231 232 static void 233 me_clone_destroy(struct ifnet *ifp) 234 { 235 struct me_softc *sc; 236 237 sx_xlock(&me_ioctl_sx); 238 sc = ifp->if_softc; 239 me_delete_tunnel(sc); 240 bpfdetach(ifp); 241 if_detach(ifp); 242 ifp->if_softc = NULL; 243 sx_xunlock(&me_ioctl_sx); 244 245 ME_WAIT(); 246 if_free(ifp); 247 free(sc, M_IFME); 248 } 249 250 static int 251 me_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 252 { 253 struct ifreq *ifr = (struct ifreq *)data; 254 struct sockaddr_in *src, *dst; 255 struct me_softc *sc; 256 int error; 257 258 switch (cmd) { 259 case SIOCSIFMTU: 260 if (ifr->ifr_mtu < 576) 261 return (EINVAL); 262 ifp->if_mtu = ifr->ifr_mtu; 263 return (0); 264 case SIOCSIFADDR: 265 ifp->if_flags |= IFF_UP; 266 case SIOCSIFFLAGS: 267 case SIOCADDMULTI: 268 case SIOCDELMULTI: 269 return (0); 270 } 271 sx_xlock(&me_ioctl_sx); 272 sc = ifp->if_softc; 273 if (sc == NULL) { 274 error = ENXIO; 275 goto end; 276 } 277 error = 0; 278 switch (cmd) { 279 case SIOCSIFPHYADDR: 280 src = &((struct in_aliasreq *)data)->ifra_addr; 281 dst = &((struct in_aliasreq *)data)->ifra_dstaddr; 282 if (src->sin_family != dst->sin_family || 283 src->sin_family != AF_INET || 284 src->sin_len != dst->sin_len || 285 src->sin_len != sizeof(struct sockaddr_in)) { 286 error = EINVAL; 287 break; 288 } 289 if (src->sin_addr.s_addr == INADDR_ANY || 290 dst->sin_addr.s_addr == INADDR_ANY) { 291 error = EADDRNOTAVAIL; 292 break; 293 } 294 error = me_set_tunnel(sc, src->sin_addr.s_addr, 295 dst->sin_addr.s_addr); 296 break; 297 case SIOCDIFPHYADDR: 298 me_delete_tunnel(sc); 299 break; 300 case SIOCGIFPSRCADDR: 301 case SIOCGIFPDSTADDR: 302 if (!ME_READY(sc)) { 303 error = EADDRNOTAVAIL; 304 break; 305 } 306 src = (struct sockaddr_in *)&ifr->ifr_addr; 307 memset(src, 0, sizeof(*src)); 308 src->sin_family = AF_INET; 309 src->sin_len = sizeof(*src); 310 switch (cmd) { 311 case SIOCGIFPSRCADDR: 312 src->sin_addr = sc->me_src; 313 break; 314 case SIOCGIFPDSTADDR: 315 src->sin_addr = sc->me_dst; 316 break; 317 } 318 error = prison_if(curthread->td_ucred, sintosa(src)); 319 if (error != 0) 320 memset(src, 0, sizeof(*src)); 321 break; 322 case SIOCGTUNFIB: 323 ifr->ifr_fib = sc->me_fibnum; 324 break; 325 case SIOCSTUNFIB: 326 if ((error = priv_check(curthread, PRIV_NET_ME)) != 0) 327 break; 328 if (ifr->ifr_fib >= rt_numfibs) 329 error = EINVAL; 330 else 331 sc->me_fibnum = ifr->ifr_fib; 332 break; 333 default: 334 error = EINVAL; 335 break; 336 } 337 end: 338 sx_xunlock(&me_ioctl_sx); 339 return (error); 340 } 341 342 static int 343 me_lookup(const struct mbuf *m, int off, int proto, void **arg) 344 { 345 const struct ip *ip; 346 struct me_softc *sc; 347 348 if (V_me_hashtbl == NULL) 349 return (0); 350 351 NET_EPOCH_ASSERT(); 352 ip = mtod(m, const struct ip *); 353 CK_LIST_FOREACH(sc, &ME_HASH(ip->ip_dst.s_addr, 354 ip->ip_src.s_addr), chain) { 355 if (sc->me_src.s_addr == ip->ip_dst.s_addr && 356 sc->me_dst.s_addr == ip->ip_src.s_addr) { 357 if ((ME2IFP(sc)->if_flags & IFF_UP) == 0) 358 return (0); 359 *arg = sc; 360 return (ENCAP_DRV_LOOKUP); 361 } 362 } 363 return (0); 364 } 365 366 /* 367 * Check that ingress address belongs to local host. 368 */ 369 static void 370 me_set_running(struct me_softc *sc) 371 { 372 373 if (in_localip(sc->me_src)) 374 ME2IFP(sc)->if_drv_flags |= IFF_DRV_RUNNING; 375 else 376 ME2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING; 377 } 378 379 /* 380 * ifaddr_event handler. 381 * Clear IFF_DRV_RUNNING flag when ingress address disappears to prevent 382 * source address spoofing. 383 */ 384 static void 385 me_srcaddr(void *arg __unused, const struct sockaddr *sa, 386 int event __unused) 387 { 388 const struct sockaddr_in *sin; 389 struct me_softc *sc; 390 391 /* Check that VNET is ready */ 392 if (V_me_hashtbl == NULL) 393 return; 394 395 NET_EPOCH_ASSERT(); 396 sin = (const struct sockaddr_in *)sa; 397 CK_LIST_FOREACH(sc, &ME_SRCHASH(sin->sin_addr.s_addr), srchash) { 398 if (sc->me_src.s_addr != sin->sin_addr.s_addr) 399 continue; 400 me_set_running(sc); 401 } 402 } 403 404 static int 405 me_set_tunnel(struct me_softc *sc, in_addr_t src, in_addr_t dst) 406 { 407 struct epoch_tracker et; 408 struct me_softc *tmp; 409 410 sx_assert(&me_ioctl_sx, SA_XLOCKED); 411 412 if (V_me_hashtbl == NULL) { 413 V_me_hashtbl = me_hashinit(); 414 V_me_srchashtbl = me_hashinit(); 415 } 416 417 if (sc->me_src.s_addr == src && sc->me_dst.s_addr == dst) 418 return (0); 419 420 CK_LIST_FOREACH(tmp, &ME_HASH(src, dst), chain) { 421 if (tmp == sc) 422 continue; 423 if (tmp->me_src.s_addr == src && 424 tmp->me_dst.s_addr == dst) 425 return (EADDRNOTAVAIL); 426 } 427 428 me_delete_tunnel(sc); 429 sc->me_dst.s_addr = dst; 430 sc->me_src.s_addr = src; 431 CK_LIST_INSERT_HEAD(&ME_HASH(src, dst), sc, chain); 432 CK_LIST_INSERT_HEAD(&ME_SRCHASH(src), sc, srchash); 433 434 NET_EPOCH_ENTER(et); 435 me_set_running(sc); 436 NET_EPOCH_EXIT(et); 437 if_link_state_change(ME2IFP(sc), LINK_STATE_UP); 438 return (0); 439 } 440 441 static void 442 me_delete_tunnel(struct me_softc *sc) 443 { 444 445 sx_assert(&me_ioctl_sx, SA_XLOCKED); 446 if (ME_READY(sc)) { 447 CK_LIST_REMOVE(sc, chain); 448 CK_LIST_REMOVE(sc, srchash); 449 ME_WAIT(); 450 451 sc->me_src.s_addr = 0; 452 sc->me_dst.s_addr = 0; 453 ME2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING; 454 if_link_state_change(ME2IFP(sc), LINK_STATE_DOWN); 455 } 456 } 457 458 static uint16_t 459 me_in_cksum(uint16_t *p, int nwords) 460 { 461 uint32_t sum = 0; 462 463 while (nwords-- > 0) 464 sum += *p++; 465 sum = (sum >> 16) + (sum & 0xffff); 466 sum += (sum >> 16); 467 return (~sum); 468 } 469 470 static int 471 me_input(struct mbuf *m, int off, int proto, void *arg) 472 { 473 struct me_softc *sc = arg; 474 struct mobhdr *mh; 475 struct ifnet *ifp; 476 struct ip *ip; 477 int hlen; 478 479 NET_EPOCH_ASSERT(); 480 481 ifp = ME2IFP(sc); 482 /* checks for short packets */ 483 hlen = sizeof(struct mobhdr); 484 if (m->m_pkthdr.len < sizeof(struct ip) + hlen) 485 hlen -= sizeof(struct in_addr); 486 if (m->m_len < sizeof(struct ip) + hlen) 487 m = m_pullup(m, sizeof(struct ip) + hlen); 488 if (m == NULL) 489 goto drop; 490 mh = (struct mobhdr *)mtodo(m, sizeof(struct ip)); 491 /* check for wrong flags */ 492 if (mh->mob_flags & (~MOB_FLAGS_SP)) { 493 m_freem(m); 494 goto drop; 495 } 496 if (mh->mob_flags) { 497 if (hlen != sizeof(struct mobhdr)) { 498 m_freem(m); 499 goto drop; 500 } 501 } else 502 hlen = sizeof(struct mobhdr) - sizeof(struct in_addr); 503 /* check mobile header checksum */ 504 if (me_in_cksum((uint16_t *)mh, hlen / sizeof(uint16_t)) != 0) { 505 m_freem(m); 506 goto drop; 507 } 508 #ifdef MAC 509 mac_ifnet_create_mbuf(ifp, m); 510 #endif 511 ip = mtod(m, struct ip *); 512 ip->ip_dst = mh->mob_dst; 513 ip->ip_p = mh->mob_proto; 514 ip->ip_sum = 0; 515 ip->ip_len = htons(m->m_pkthdr.len - hlen); 516 if (mh->mob_flags) 517 ip->ip_src = mh->mob_src; 518 memmove(mtodo(m, hlen), ip, sizeof(struct ip)); 519 m_adj(m, hlen); 520 m_clrprotoflags(m); 521 m->m_pkthdr.rcvif = ifp; 522 m->m_pkthdr.csum_flags |= (CSUM_IP_CHECKED | CSUM_IP_VALID); 523 M_SETFIB(m, ifp->if_fib); 524 hlen = AF_INET; 525 BPF_MTAP2(ifp, &hlen, sizeof(hlen), m); 526 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 527 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 528 if ((ifp->if_flags & IFF_MONITOR) != 0) 529 m_freem(m); 530 else 531 netisr_dispatch(NETISR_IP, m); 532 return (IPPROTO_DONE); 533 drop: 534 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 535 return (IPPROTO_DONE); 536 } 537 538 static int 539 me_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 540 struct route *ro) 541 { 542 uint32_t af; 543 544 if (dst->sa_family == AF_UNSPEC) 545 bcopy(dst->sa_data, &af, sizeof(af)); 546 else 547 af = RO_GET_FAMILY(ro, dst); 548 m->m_pkthdr.csum_data = af; 549 return (ifp->if_transmit(ifp, m)); 550 } 551 552 #define MTAG_ME 1414491977 553 static int 554 me_transmit(struct ifnet *ifp, struct mbuf *m) 555 { 556 ME_RLOCK_TRACKER; 557 struct mobhdr mh; 558 struct me_softc *sc; 559 struct ip *ip; 560 uint32_t af; 561 int error, hlen, plen; 562 563 ME_RLOCK(); 564 #ifdef MAC 565 error = mac_ifnet_check_transmit(ifp, m); 566 if (error != 0) 567 goto drop; 568 #endif 569 error = ENETDOWN; 570 sc = ifp->if_softc; 571 if (sc == NULL || !ME_READY(sc) || 572 (ifp->if_flags & IFF_MONITOR) != 0 || 573 (ifp->if_flags & IFF_UP) == 0 || 574 (ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 || 575 (error = if_tunnel_check_nesting(ifp, m, MTAG_ME, 576 V_max_me_nesting)) != 0) { 577 m_freem(m); 578 goto drop; 579 } 580 af = m->m_pkthdr.csum_data; 581 if (af != AF_INET) { 582 error = EAFNOSUPPORT; 583 m_freem(m); 584 goto drop; 585 } 586 if (m->m_len < sizeof(struct ip)) 587 m = m_pullup(m, sizeof(struct ip)); 588 if (m == NULL) { 589 error = ENOBUFS; 590 goto drop; 591 } 592 ip = mtod(m, struct ip *); 593 /* Fragmented datagramms shouldn't be encapsulated */ 594 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) { 595 error = EINVAL; 596 m_freem(m); 597 goto drop; 598 } 599 mh.mob_proto = ip->ip_p; 600 mh.mob_src = ip->ip_src; 601 mh.mob_dst = ip->ip_dst; 602 if (in_hosteq(sc->me_src, ip->ip_src)) { 603 hlen = sizeof(struct mobhdr) - sizeof(struct in_addr); 604 mh.mob_flags = 0; 605 } else { 606 hlen = sizeof(struct mobhdr); 607 mh.mob_flags = MOB_FLAGS_SP; 608 } 609 BPF_MTAP2(ifp, &af, sizeof(af), m); 610 plen = m->m_pkthdr.len; 611 ip->ip_src = sc->me_src; 612 ip->ip_dst = sc->me_dst; 613 m->m_flags &= ~(M_BCAST|M_MCAST); 614 M_SETFIB(m, sc->me_fibnum); 615 M_PREPEND(m, hlen, M_NOWAIT); 616 if (m == NULL) { 617 error = ENOBUFS; 618 goto drop; 619 } 620 if (m->m_len < sizeof(struct ip) + hlen) 621 m = m_pullup(m, sizeof(struct ip) + hlen); 622 if (m == NULL) { 623 error = ENOBUFS; 624 goto drop; 625 } 626 memmove(mtod(m, void *), mtodo(m, hlen), sizeof(struct ip)); 627 ip = mtod(m, struct ip *); 628 ip->ip_len = htons(m->m_pkthdr.len); 629 ip->ip_p = IPPROTO_MOBILE; 630 ip->ip_sum = 0; 631 mh.mob_csum = 0; 632 mh.mob_csum = me_in_cksum((uint16_t *)&mh, hlen / sizeof(uint16_t)); 633 bcopy(&mh, mtodo(m, sizeof(struct ip)), hlen); 634 error = ip_output(m, NULL, NULL, IP_FORWARDING, NULL, NULL); 635 drop: 636 if (error) 637 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 638 else { 639 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 640 if_inc_counter(ifp, IFCOUNTER_OBYTES, plen); 641 } 642 ME_RUNLOCK(); 643 return (error); 644 } 645 646 static void 647 me_qflush(struct ifnet *ifp __unused) 648 { 649 650 } 651 652 static const struct srcaddrtab *me_srcaddrtab = NULL; 653 static const struct encaptab *ecookie = NULL; 654 static const struct encap_config me_encap_cfg = { 655 .proto = IPPROTO_MOBILE, 656 .min_length = sizeof(struct ip) + sizeof(struct mobhdr) - 657 sizeof(in_addr_t), 658 .exact_match = ENCAP_DRV_LOOKUP, 659 .lookup = me_lookup, 660 .input = me_input 661 }; 662 663 static int 664 memodevent(module_t mod, int type, void *data) 665 { 666 667 switch (type) { 668 case MOD_LOAD: 669 me_srcaddrtab = ip_encap_register_srcaddr(me_srcaddr, 670 NULL, M_WAITOK); 671 ecookie = ip_encap_attach(&me_encap_cfg, NULL, M_WAITOK); 672 break; 673 case MOD_UNLOAD: 674 ip_encap_detach(ecookie); 675 ip_encap_unregister_srcaddr(me_srcaddrtab); 676 break; 677 default: 678 return (EOPNOTSUPP); 679 } 680 return (0); 681 } 682 683 static moduledata_t me_mod = { 684 "if_me", 685 memodevent, 686 0 687 }; 688 689 DECLARE_MODULE(if_me, me_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 690 MODULE_VERSION(if_me, 1); 691