if_l2tp.c revision 1.12
1 /* $NetBSD: if_l2tp.c,v 1.12 2017/10/19 11:28:30 knakahara Exp $ */ 2 3 /* 4 * Copyright (c) 2017 Internet Initiative Japan Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /* 30 * L2TPv3 kernel interface 31 */ 32 33 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: if_l2tp.c,v 1.12 2017/10/19 11:28:30 knakahara Exp $"); 35 36 #ifdef _KERNEL_OPT 37 #include "opt_inet.h" 38 #endif 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/kernel.h> 43 #include <sys/mbuf.h> 44 #include <sys/socket.h> 45 #include <sys/sockio.h> 46 #include <sys/errno.h> 47 #include <sys/ioctl.h> 48 #include <sys/time.h> 49 #include <sys/syslog.h> 50 #include <sys/proc.h> 51 #include <sys/conf.h> 52 #include <sys/kauth.h> 53 #include <sys/cpu.h> 54 #include <sys/cprng.h> 55 #include <sys/intr.h> 56 #include <sys/kmem.h> 57 #include <sys/mutex.h> 58 #include <sys/atomic.h> 59 #include <sys/pserialize.h> 60 #include <sys/device.h> 61 #include <sys/module.h> 62 63 #include <net/if.h> 64 #include <net/if_dl.h> 65 #include <net/if_ether.h> 66 #include <net/if_types.h> 67 #include <net/netisr.h> 68 #include <net/route.h> 69 #include <net/bpf.h> 70 #include <net/if_vlanvar.h> 71 72 #include <netinet/in.h> 73 #include <netinet/in_systm.h> 74 #include <netinet/ip.h> 75 #include <netinet/ip_encap.h> 76 #ifdef INET 77 #include <netinet/in_var.h> 78 #include <netinet/in_l2tp.h> 79 #endif /* INET */ 80 #ifdef INET6 81 #include <netinet6/in6_l2tp.h> 82 #endif 83 84 #include <net/if_l2tp.h> 85 86 #include <net/if_vlanvar.h> 87 88 /* TODO: IP_TCPMSS support */ 89 #undef IP_TCPMSS 90 #ifdef IP_TCPMSS 91 #include <netinet/ip_tcpmss.h> 92 #endif 93 94 #include <net/bpf.h> 95 #include <net/net_osdep.h> 96 97 /* 98 * l2tp global variable definitions 99 */ 100 LIST_HEAD(l2tp_sclist, l2tp_softc); 101 static struct { 102 struct l2tp_sclist list; 103 kmutex_t lock; 104 } l2tp_softcs __cacheline_aligned; 105 106 107 #if !defined(L2TP_ID_HASH_SIZE) 108 #define L2TP_ID_HASH_SIZE 64 109 #endif 110 static struct { 111 kmutex_t lock; 112 struct pslist_head *lists; 113 u_long mask; 114 } l2tp_hash __cacheline_aligned = { 115 .lists = NULL, 116 }; 117 118 pserialize_t l2tp_psz __read_mostly; 119 struct psref_class *lv_psref_class __read_mostly; 120 121 static void l2tp_ro_init_pc(void *, void *, struct cpu_info *); 122 static void l2tp_ro_fini_pc(void *, void *, struct cpu_info *); 123 124 static int l2tp_clone_create(struct if_clone *, int); 125 static int l2tp_clone_destroy(struct ifnet *); 126 127 struct if_clone l2tp_cloner = 128 IF_CLONE_INITIALIZER("l2tp", l2tp_clone_create, l2tp_clone_destroy); 129 130 static int l2tp_output(struct ifnet *, struct mbuf *, 131 const struct sockaddr *, const struct rtentry *); 132 static void l2tpintr(struct l2tp_variant *); 133 134 static void l2tp_hash_init(void); 135 static int l2tp_hash_fini(void); 136 137 static void l2tp_start(struct ifnet *); 138 static int l2tp_transmit(struct ifnet *, struct mbuf *); 139 140 static int l2tp_set_tunnel(struct ifnet *, struct sockaddr *, 141 struct sockaddr *); 142 static void l2tp_delete_tunnel(struct ifnet *); 143 144 static int id_hash_func(uint32_t, u_long); 145 146 static void l2tp_variant_update(struct l2tp_softc *, struct l2tp_variant *); 147 static int l2tp_set_session(struct l2tp_softc *, uint32_t, uint32_t); 148 static int l2tp_clear_session(struct l2tp_softc *); 149 static int l2tp_set_cookie(struct l2tp_softc *, uint64_t, u_int, uint64_t, u_int); 150 static void l2tp_clear_cookie(struct l2tp_softc *); 151 static void l2tp_set_state(struct l2tp_softc *, int); 152 static int l2tp_encap_attach(struct l2tp_variant *); 153 static int l2tp_encap_detach(struct l2tp_variant *); 154 155 #ifndef MAX_L2TP_NEST 156 /* 157 * This macro controls the upper limitation on nesting of l2tp tunnels. 158 * Since, setting a large value to this macro with a careless configuration 159 * may introduce system crash, we don't allow any nestings by default. 160 * If you need to configure nested l2tp tunnels, you can define this macro 161 * in your kernel configuration file. However, if you do so, please be 162 * careful to configure the tunnels so that it won't make a loop. 163 */ 164 /* 165 * XXX 166 * Currently, if in_l2tp_output recursively calls, it causes locking against 167 * myself of struct l2tp_ro->lr_lock. So, nested l2tp tunnels is prohibited. 168 */ 169 #define MAX_L2TP_NEST 0 170 #endif 171 172 static int max_l2tp_nesting = MAX_L2TP_NEST; 173 174 /* ARGSUSED */ 175 void 176 l2tpattach(int count) 177 { 178 /* 179 * Nothing to do here, initialization is handled by the 180 * module initialization code in l2tpinit() below). 181 */ 182 } 183 184 static void 185 l2tpinit(void) 186 { 187 188 mutex_init(&l2tp_softcs.lock, MUTEX_DEFAULT, IPL_NONE); 189 LIST_INIT(&l2tp_softcs.list); 190 191 mutex_init(&l2tp_hash.lock, MUTEX_DEFAULT, IPL_NONE); 192 l2tp_psz = pserialize_create(); 193 lv_psref_class = psref_class_create("l2tpvar", IPL_SOFTNET); 194 if_clone_attach(&l2tp_cloner); 195 196 l2tp_hash_init(); 197 } 198 199 static int 200 l2tpdetach(void) 201 { 202 int error; 203 204 mutex_enter(&l2tp_softcs.lock); 205 if (!LIST_EMPTY(&l2tp_softcs.list)) { 206 mutex_exit(&l2tp_softcs.lock); 207 return EBUSY; 208 } 209 mutex_exit(&l2tp_softcs.lock); 210 211 error = l2tp_hash_fini(); 212 if (error) 213 return error; 214 215 if_clone_detach(&l2tp_cloner); 216 psref_class_destroy(lv_psref_class); 217 pserialize_destroy(l2tp_psz); 218 mutex_destroy(&l2tp_hash.lock); 219 220 mutex_destroy(&l2tp_softcs.lock); 221 222 return error; 223 } 224 225 static int 226 l2tp_clone_create(struct if_clone *ifc, int unit) 227 { 228 struct l2tp_softc *sc; 229 struct l2tp_variant *var; 230 231 sc = kmem_zalloc(sizeof(struct l2tp_softc), KM_SLEEP); 232 var = kmem_zalloc(sizeof(struct l2tp_variant), KM_SLEEP); 233 234 var->lv_softc = sc; 235 var->lv_state = L2TP_STATE_DOWN; 236 var->lv_use_cookie = L2TP_COOKIE_OFF; 237 psref_target_init(&var->lv_psref, lv_psref_class); 238 239 sc->l2tp_var = var; 240 mutex_init(&sc->l2tp_lock, MUTEX_DEFAULT, IPL_NONE); 241 PSLIST_ENTRY_INIT(sc, l2tp_hash); 242 243 if_initname(&sc->l2tp_ec.ec_if, ifc->ifc_name, unit); 244 245 l2tpattach0(sc); 246 247 sc->l2tp_ro_percpu = percpu_alloc(sizeof(struct l2tp_ro)); 248 percpu_foreach(sc->l2tp_ro_percpu, l2tp_ro_init_pc, NULL); 249 250 mutex_enter(&l2tp_softcs.lock); 251 LIST_INSERT_HEAD(&l2tp_softcs.list, sc, l2tp_list); 252 mutex_exit(&l2tp_softcs.lock); 253 254 return (0); 255 } 256 257 void 258 l2tpattach0(struct l2tp_softc *sc) 259 { 260 261 sc->l2tp_ec.ec_if.if_addrlen = 0; 262 sc->l2tp_ec.ec_if.if_mtu = L2TP_MTU; 263 sc->l2tp_ec.ec_if.if_flags = IFF_POINTOPOINT|IFF_MULTICAST|IFF_SIMPLEX; 264 sc->l2tp_ec.ec_if.if_extflags = IFEF_OUTPUT_MPSAFE|IFEF_START_MPSAFE; 265 sc->l2tp_ec.ec_if.if_ioctl = l2tp_ioctl; 266 sc->l2tp_ec.ec_if.if_output = l2tp_output; 267 sc->l2tp_ec.ec_if.if_type = IFT_L2TP; 268 sc->l2tp_ec.ec_if.if_dlt = DLT_NULL; 269 sc->l2tp_ec.ec_if.if_start = l2tp_start; 270 sc->l2tp_ec.ec_if.if_transmit = l2tp_transmit; 271 sc->l2tp_ec.ec_if._if_input = ether_input; 272 IFQ_SET_READY(&sc->l2tp_ec.ec_if.if_snd); 273 if_attach(&sc->l2tp_ec.ec_if); 274 if_alloc_sadl(&sc->l2tp_ec.ec_if); 275 bpf_attach(&sc->l2tp_ec.ec_if, DLT_EN10MB, sizeof(struct ether_header)); 276 } 277 278 void 279 l2tp_ro_init_pc(void *p, void *arg __unused, struct cpu_info *ci __unused) 280 { 281 struct l2tp_ro *lro = p; 282 283 mutex_init(&lro->lr_lock, MUTEX_DEFAULT, IPL_NONE); 284 } 285 286 void 287 l2tp_ro_fini_pc(void *p, void *arg __unused, struct cpu_info *ci __unused) 288 { 289 struct l2tp_ro *lro = p; 290 291 rtcache_free(&lro->lr_ro); 292 293 mutex_destroy(&lro->lr_lock); 294 } 295 296 static int 297 l2tp_clone_destroy(struct ifnet *ifp) 298 { 299 struct l2tp_variant *var; 300 struct l2tp_softc *sc = container_of(ifp, struct l2tp_softc, 301 l2tp_ec.ec_if); 302 303 l2tp_clear_session(sc); 304 l2tp_delete_tunnel(&sc->l2tp_ec.ec_if); 305 /* 306 * To avoid for l2tp_transmit() to access sc->l2tp_var after free it. 307 */ 308 mutex_enter(&sc->l2tp_lock); 309 var = sc->l2tp_var; 310 l2tp_variant_update(sc, NULL); 311 mutex_exit(&sc->l2tp_lock); 312 313 mutex_enter(&l2tp_softcs.lock); 314 LIST_REMOVE(sc, l2tp_list); 315 mutex_exit(&l2tp_softcs.lock); 316 317 bpf_detach(ifp); 318 319 if_detach(ifp); 320 321 percpu_foreach(sc->l2tp_ro_percpu, l2tp_ro_fini_pc, NULL); 322 percpu_free(sc->l2tp_ro_percpu, sizeof(struct l2tp_ro)); 323 324 kmem_free(var, sizeof(struct l2tp_variant)); 325 mutex_destroy(&sc->l2tp_lock); 326 kmem_free(sc, sizeof(struct l2tp_softc)); 327 328 return 0; 329 } 330 331 static int 332 l2tp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 333 const struct rtentry *rt) 334 { 335 struct l2tp_softc *sc = container_of(ifp, struct l2tp_softc, 336 l2tp_ec.ec_if); 337 struct l2tp_variant *var; 338 struct psref psref; 339 int error = 0; 340 341 var = l2tp_getref_variant(sc, &psref); 342 if (var == NULL) { 343 m_freem(m); 344 return ENETDOWN; 345 } 346 347 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family); 348 349 m->m_flags &= ~(M_BCAST|M_MCAST); 350 351 if ((ifp->if_flags & IFF_UP) == 0) { 352 m_freem(m); 353 error = ENETDOWN; 354 goto end; 355 } 356 357 if (var->lv_psrc == NULL || var->lv_pdst == NULL) { 358 m_freem(m); 359 error = ENETDOWN; 360 goto end; 361 } 362 363 /* XXX should we check if our outer source is legal? */ 364 365 /* use DLT_NULL encapsulation here to pass inner af type */ 366 M_PREPEND(m, sizeof(int), M_DONTWAIT); 367 if (!m) { 368 error = ENOBUFS; 369 goto end; 370 } 371 *mtod(m, int *) = dst->sa_family; 372 373 IFQ_ENQUEUE(&ifp->if_snd, m, error); 374 if (error) 375 goto end; 376 377 /* 378 * direct call to avoid infinite loop at l2tpintr() 379 */ 380 l2tpintr(var); 381 382 error = 0; 383 384 end: 385 l2tp_putref_variant(var, &psref); 386 if (error) 387 ifp->if_oerrors++; 388 389 return error; 390 } 391 392 static void 393 l2tpintr(struct l2tp_variant *var) 394 { 395 struct l2tp_softc *sc; 396 struct ifnet *ifp; 397 struct mbuf *m; 398 int error; 399 400 KASSERT(psref_held(&var->lv_psref, lv_psref_class)); 401 402 sc = var->lv_softc; 403 ifp = &sc->l2tp_ec.ec_if; 404 405 /* output processing */ 406 if (var->lv_my_sess_id == 0 || var->lv_peer_sess_id == 0) { 407 IFQ_PURGE(&ifp->if_snd); 408 return; 409 } 410 411 for (;;) { 412 IFQ_DEQUEUE(&ifp->if_snd, m); 413 if (m == NULL) 414 break; 415 m->m_flags &= ~(M_BCAST|M_MCAST); 416 bpf_mtap(ifp, m); 417 switch (var->lv_psrc->sa_family) { 418 #ifdef INET 419 case AF_INET: 420 error = in_l2tp_output(var, m); 421 break; 422 #endif 423 #ifdef INET6 424 case AF_INET6: 425 error = in6_l2tp_output(var, m); 426 break; 427 #endif 428 default: 429 m_freem(m); 430 error = ENETDOWN; 431 break; 432 } 433 434 if (error) 435 ifp->if_oerrors++; 436 else { 437 ifp->if_opackets++; 438 /* 439 * obytes is incremented at ether_output() or 440 * bridge_enqueue(). 441 */ 442 } 443 } 444 445 } 446 447 void 448 l2tp_input(struct mbuf *m, struct ifnet *ifp) 449 { 450 451 KASSERT(ifp != NULL); 452 453 if (0 == (mtod(m, u_long) & 0x03)) { 454 /* copy and align head of payload */ 455 struct mbuf *m_head; 456 int copy_length; 457 458 #define L2TP_COPY_LENGTH 60 459 #define L2TP_LINK_HDR_ROOM (MHLEN - L2TP_COPY_LENGTH - 4/*round4(2)*/) 460 461 if (m->m_pkthdr.len < L2TP_COPY_LENGTH) { 462 copy_length = m->m_pkthdr.len; 463 } else { 464 copy_length = L2TP_COPY_LENGTH; 465 } 466 467 if (m->m_len < copy_length) { 468 m = m_pullup(m, copy_length); 469 if (m == NULL) 470 return; 471 } 472 473 MGETHDR(m_head, M_DONTWAIT, MT_HEADER); 474 if (m_head == NULL) { 475 m_freem(m); 476 return; 477 } 478 M_COPY_PKTHDR(m_head, m); 479 480 m_head->m_data += 2 /* align */ + L2TP_LINK_HDR_ROOM; 481 memcpy(m_head->m_data, m->m_data, copy_length); 482 m_head->m_len = copy_length; 483 m->m_data += copy_length; 484 m->m_len -= copy_length; 485 486 /* construct chain */ 487 if (m->m_len == 0) { 488 m_head->m_next = m_free(m); /* not m_freem */ 489 } else { 490 /* 491 * copyed mtag in previous call M_COPY_PKTHDR 492 * but don't delete mtag in case cutt of M_PKTHDR flag 493 */ 494 m_tag_delete_chain(m, NULL); 495 m->m_flags &= ~M_PKTHDR; 496 m_head->m_next = m; 497 } 498 499 /* override m */ 500 m = m_head; 501 } 502 503 m_set_rcvif(m, ifp); 504 505 /* 506 * bpf_mtap() and ifp->if_ipackets++ is done in if_input() 507 * 508 * obytes is incremented at ether_output() or bridge_enqueue(). 509 */ 510 if_percpuq_enqueue(ifp->if_percpuq, m); 511 } 512 513 void 514 l2tp_start(struct ifnet *ifp) 515 { 516 struct psref psref; 517 struct l2tp_variant *var; 518 struct l2tp_softc *sc = container_of(ifp, struct l2tp_softc, 519 l2tp_ec.ec_if); 520 521 var = l2tp_getref_variant(sc, &psref); 522 if (var == NULL) 523 return; 524 525 if (var->lv_psrc == NULL || var->lv_pdst == NULL) 526 return; 527 528 l2tpintr(var); 529 l2tp_putref_variant(var, &psref); 530 } 531 532 int 533 l2tp_transmit(struct ifnet *ifp, struct mbuf *m) 534 { 535 int error; 536 struct psref psref; 537 struct l2tp_variant *var; 538 struct l2tp_softc *sc = container_of(ifp, struct l2tp_softc, 539 l2tp_ec.ec_if); 540 541 var = l2tp_getref_variant(sc, &psref); 542 if (var == NULL) { 543 m_freem(m); 544 return ENETDOWN; 545 } 546 547 if (var->lv_psrc == NULL || var->lv_pdst == NULL) { 548 m_freem(m); 549 error = ENETDOWN; 550 goto out; 551 } 552 553 m->m_flags &= ~(M_BCAST|M_MCAST); 554 bpf_mtap(ifp, m); 555 switch (var->lv_psrc->sa_family) { 556 #ifdef INET 557 case AF_INET: 558 error = in_l2tp_output(var, m); 559 break; 560 #endif 561 #ifdef INET6 562 case AF_INET6: 563 error = in6_l2tp_output(var, m); 564 break; 565 #endif 566 default: 567 m_freem(m); 568 error = ENETDOWN; 569 break; 570 } 571 572 if (error) 573 ifp->if_oerrors++; 574 else { 575 ifp->if_opackets++; 576 /* 577 * obytes is incremented at ether_output() or bridge_enqueue(). 578 */ 579 } 580 581 out: 582 l2tp_putref_variant(var, &psref); 583 return error; 584 } 585 586 /* XXX how should we handle IPv6 scope on SIOC[GS]IFPHYADDR? */ 587 int 588 l2tp_ioctl(struct ifnet *ifp, u_long cmd, void *data) 589 { 590 struct l2tp_softc *sc = container_of(ifp, struct l2tp_softc, 591 l2tp_ec.ec_if); 592 struct l2tp_variant *var, *var_tmp; 593 struct ifreq *ifr = data; 594 int error = 0, size; 595 struct sockaddr *dst, *src; 596 struct l2tp_req l2tpr; 597 u_long mtu; 598 int bound; 599 struct psref psref; 600 601 switch (cmd) { 602 case SIOCSIFADDR: 603 ifp->if_flags |= IFF_UP; 604 break; 605 606 case SIOCSIFDSTADDR: 607 break; 608 609 case SIOCADDMULTI: 610 case SIOCDELMULTI: 611 switch (ifr->ifr_addr.sa_family) { 612 #ifdef INET 613 case AF_INET: /* IP supports Multicast */ 614 break; 615 #endif /* INET */ 616 #ifdef INET6 617 case AF_INET6: /* IP6 supports Multicast */ 618 break; 619 #endif /* INET6 */ 620 default: /* Other protocols doesn't support Multicast */ 621 error = EAFNOSUPPORT; 622 break; 623 } 624 break; 625 626 case SIOCSIFMTU: 627 mtu = ifr->ifr_mtu; 628 if (mtu < L2TP_MTU_MIN || mtu > L2TP_MTU_MAX) 629 return (EINVAL); 630 ifp->if_mtu = mtu; 631 break; 632 633 #ifdef INET 634 case SIOCSIFPHYADDR: 635 src = (struct sockaddr *) 636 &(((struct in_aliasreq *)data)->ifra_addr); 637 dst = (struct sockaddr *) 638 &(((struct in_aliasreq *)data)->ifra_dstaddr); 639 if (src->sa_family != AF_INET || dst->sa_family != AF_INET) 640 return EAFNOSUPPORT; 641 else if (src->sa_len != sizeof(struct sockaddr_in) 642 || dst->sa_len != sizeof(struct sockaddr_in)) 643 return EINVAL; 644 645 error = l2tp_set_tunnel(&sc->l2tp_ec.ec_if, src, dst); 646 break; 647 648 #endif /* INET */ 649 #ifdef INET6 650 case SIOCSIFPHYADDR_IN6: 651 src = (struct sockaddr *) 652 &(((struct in6_aliasreq *)data)->ifra_addr); 653 dst = (struct sockaddr *) 654 &(((struct in6_aliasreq *)data)->ifra_dstaddr); 655 if (src->sa_family != AF_INET6 || dst->sa_family != AF_INET6) 656 return EAFNOSUPPORT; 657 else if (src->sa_len != sizeof(struct sockaddr_in6) 658 || dst->sa_len != sizeof(struct sockaddr_in6)) 659 return EINVAL; 660 661 error = l2tp_set_tunnel(&sc->l2tp_ec.ec_if, src, dst); 662 break; 663 664 #endif /* INET6 */ 665 case SIOCSLIFPHYADDR: 666 src = (struct sockaddr *) 667 &(((struct if_laddrreq *)data)->addr); 668 dst = (struct sockaddr *) 669 &(((struct if_laddrreq *)data)->dstaddr); 670 if (src->sa_family != dst->sa_family) 671 return EINVAL; 672 else if (src->sa_family == AF_INET 673 && src->sa_len != sizeof(struct sockaddr_in)) 674 return EINVAL; 675 else if (src->sa_family == AF_INET6 676 && src->sa_len != sizeof(struct sockaddr_in6)) 677 return EINVAL; 678 else if (dst->sa_family == AF_INET 679 && dst->sa_len != sizeof(struct sockaddr_in)) 680 return EINVAL; 681 else if (dst->sa_family == AF_INET6 682 && dst->sa_len != sizeof(struct sockaddr_in6)) 683 return EINVAL; 684 685 error = l2tp_set_tunnel(&sc->l2tp_ec.ec_if, src, dst); 686 break; 687 688 case SIOCDIFPHYADDR: 689 l2tp_delete_tunnel(&sc->l2tp_ec.ec_if); 690 break; 691 692 case SIOCGIFPSRCADDR: 693 #ifdef INET6 694 case SIOCGIFPSRCADDR_IN6: 695 #endif /* INET6 */ 696 bound = curlwp_bind(); 697 var = l2tp_getref_variant(sc, &psref); 698 if (var == NULL) { 699 curlwp_bindx(bound); 700 error = EADDRNOTAVAIL; 701 goto bad; 702 } 703 if (var->lv_psrc == NULL) { 704 l2tp_putref_variant(var, &psref); 705 curlwp_bindx(bound); 706 error = EADDRNOTAVAIL; 707 goto bad; 708 } 709 src = var->lv_psrc; 710 switch (cmd) { 711 #ifdef INET 712 case SIOCGIFPSRCADDR: 713 dst = &ifr->ifr_addr; 714 size = sizeof(ifr->ifr_addr); 715 break; 716 #endif /* INET */ 717 #ifdef INET6 718 case SIOCGIFPSRCADDR_IN6: 719 dst = (struct sockaddr *) 720 &(((struct in6_ifreq *)data)->ifr_addr); 721 size = sizeof(((struct in6_ifreq *)data)->ifr_addr); 722 break; 723 #endif /* INET6 */ 724 default: 725 l2tp_putref_variant(var, &psref); 726 curlwp_bindx(bound); 727 error = EADDRNOTAVAIL; 728 goto bad; 729 } 730 if (src->sa_len > size) { 731 l2tp_putref_variant(var, &psref); 732 curlwp_bindx(bound); 733 return EINVAL; 734 } 735 sockaddr_copy(dst, src->sa_len, src); 736 l2tp_putref_variant(var, &psref); 737 curlwp_bindx(bound); 738 break; 739 740 case SIOCGIFPDSTADDR: 741 #ifdef INET6 742 case SIOCGIFPDSTADDR_IN6: 743 #endif /* INET6 */ 744 bound = curlwp_bind(); 745 var = l2tp_getref_variant(sc, &psref); 746 if (var == NULL) { 747 curlwp_bindx(bound); 748 error = EADDRNOTAVAIL; 749 goto bad; 750 } 751 if (var->lv_pdst == NULL) { 752 l2tp_putref_variant(var, &psref); 753 curlwp_bindx(bound); 754 error = EADDRNOTAVAIL; 755 goto bad; 756 } 757 src = var->lv_pdst; 758 switch (cmd) { 759 #ifdef INET 760 case SIOCGIFPDSTADDR: 761 dst = &ifr->ifr_addr; 762 size = sizeof(ifr->ifr_addr); 763 break; 764 #endif /* INET */ 765 #ifdef INET6 766 case SIOCGIFPDSTADDR_IN6: 767 dst = (struct sockaddr *) 768 &(((struct in6_ifreq *)data)->ifr_addr); 769 size = sizeof(((struct in6_ifreq *)data)->ifr_addr); 770 break; 771 #endif /* INET6 */ 772 default: 773 l2tp_putref_variant(var, &psref); 774 curlwp_bindx(bound); 775 error = EADDRNOTAVAIL; 776 goto bad; 777 } 778 if (src->sa_len > size) { 779 l2tp_putref_variant(var, &psref); 780 curlwp_bindx(bound); 781 return EINVAL; 782 } 783 sockaddr_copy(dst, src->sa_len, src); 784 l2tp_putref_variant(var, &psref); 785 curlwp_bindx(bound); 786 break; 787 788 case SIOCGLIFPHYADDR: 789 bound = curlwp_bind(); 790 var = l2tp_getref_variant(sc, &psref); 791 if (var == NULL) { 792 curlwp_bindx(bound); 793 error = EADDRNOTAVAIL; 794 goto bad; 795 } 796 if (var->lv_psrc == NULL || var->lv_pdst == NULL) { 797 l2tp_putref_variant(var, &psref); 798 curlwp_bindx(bound); 799 error = EADDRNOTAVAIL; 800 goto bad; 801 } 802 803 /* copy src */ 804 src = var->lv_psrc; 805 dst = (struct sockaddr *) 806 &(((struct if_laddrreq *)data)->addr); 807 size = sizeof(((struct if_laddrreq *)data)->addr); 808 if (src->sa_len > size) { 809 l2tp_putref_variant(var, &psref); 810 curlwp_bindx(bound); 811 return EINVAL; 812 } 813 sockaddr_copy(dst, src->sa_len, src); 814 815 /* copy dst */ 816 src = var->lv_pdst; 817 dst = (struct sockaddr *) 818 &(((struct if_laddrreq *)data)->dstaddr); 819 size = sizeof(((struct if_laddrreq *)data)->dstaddr); 820 if (src->sa_len > size) { 821 l2tp_putref_variant(var, &psref); 822 curlwp_bindx(bound); 823 return EINVAL; 824 } 825 sockaddr_copy(dst, src->sa_len, src); 826 l2tp_putref_variant(var, &psref); 827 curlwp_bindx(bound); 828 break; 829 830 case SIOCSL2TPSESSION: 831 if ((error = copyin(ifr->ifr_data, &l2tpr, sizeof(l2tpr))) != 0) 832 break; 833 834 /* session id must not zero */ 835 if (l2tpr.my_sess_id == 0 || l2tpr.peer_sess_id == 0) 836 return EINVAL; 837 838 bound = curlwp_bind(); 839 var_tmp = l2tp_lookup_session_ref(l2tpr.my_sess_id, &psref); 840 if (var_tmp != NULL) { 841 /* duplicate session id */ 842 log(LOG_WARNING, "%s: duplicate session id %" PRIu32 " of %s\n", 843 sc->l2tp_ec.ec_if.if_xname, l2tpr.my_sess_id, 844 var_tmp->lv_softc->l2tp_ec.ec_if.if_xname); 845 psref_release(&psref, &var_tmp->lv_psref, 846 lv_psref_class); 847 curlwp_bindx(bound); 848 return EINVAL; 849 } 850 curlwp_bindx(bound); 851 852 error = l2tp_set_session(sc, l2tpr.my_sess_id, l2tpr.peer_sess_id); 853 break; 854 case SIOCDL2TPSESSION: 855 l2tp_clear_session(sc); 856 break; 857 case SIOCSL2TPCOOKIE: 858 if ((error = copyin(ifr->ifr_data, &l2tpr, sizeof(l2tpr))) != 0) 859 break; 860 861 error = l2tp_set_cookie(sc, l2tpr.my_cookie, l2tpr.my_cookie_len, 862 l2tpr.peer_cookie, l2tpr.peer_cookie_len); 863 break; 864 case SIOCDL2TPCOOKIE: 865 l2tp_clear_cookie(sc); 866 break; 867 case SIOCSL2TPSTATE: 868 if ((error = copyin(ifr->ifr_data, &l2tpr, sizeof(l2tpr))) != 0) 869 break; 870 871 l2tp_set_state(sc, l2tpr.state); 872 break; 873 case SIOCGL2TP: 874 /* get L2TPV3 session info */ 875 memset(&l2tpr, 0, sizeof(l2tpr)); 876 877 bound = curlwp_bind(); 878 var = l2tp_getref_variant(sc, &psref); 879 if (var == NULL) { 880 curlwp_bindx(bound); 881 error = EADDRNOTAVAIL; 882 goto bad; 883 } 884 885 l2tpr.state = var->lv_state; 886 l2tpr.my_sess_id = var->lv_my_sess_id; 887 l2tpr.peer_sess_id = var->lv_peer_sess_id; 888 l2tpr.my_cookie = var->lv_my_cookie; 889 l2tpr.my_cookie_len = var->lv_my_cookie_len; 890 l2tpr.peer_cookie = var->lv_peer_cookie; 891 l2tpr.peer_cookie_len = var->lv_peer_cookie_len; 892 l2tp_putref_variant(var, &psref); 893 curlwp_bindx(bound); 894 895 error = copyout(&l2tpr, ifr->ifr_data, sizeof(l2tpr)); 896 break; 897 898 default: 899 error = ifioctl_common(ifp, cmd, data); 900 break; 901 } 902 bad: 903 return error; 904 } 905 906 static int 907 l2tp_set_tunnel(struct ifnet *ifp, struct sockaddr *src, struct sockaddr *dst) 908 { 909 struct l2tp_softc *sc = container_of(ifp, struct l2tp_softc, 910 l2tp_ec.ec_if); 911 struct sockaddr *osrc, *odst; 912 struct sockaddr *nsrc, *ndst; 913 struct l2tp_variant *ovar, *nvar; 914 int error; 915 916 nsrc = sockaddr_dup(src, M_WAITOK); 917 ndst = sockaddr_dup(dst, M_WAITOK); 918 919 nvar = kmem_alloc(sizeof(*nvar), KM_SLEEP); 920 921 error = encap_lock_enter(); 922 if (error) 923 goto error; 924 925 mutex_enter(&sc->l2tp_lock); 926 927 ovar = sc->l2tp_var; 928 osrc = ovar->lv_psrc; 929 odst = ovar->lv_pdst; 930 *nvar = *ovar; 931 psref_target_init(&nvar->lv_psref, lv_psref_class); 932 nvar->lv_psrc = nsrc; 933 nvar->lv_pdst = ndst; 934 error = l2tp_encap_attach(nvar); 935 if (error) { 936 mutex_exit(&sc->l2tp_lock); 937 encap_lock_exit(); 938 goto error; 939 } 940 membar_producer(); 941 l2tp_variant_update(sc, nvar); 942 943 mutex_exit(&sc->l2tp_lock); 944 945 (void)l2tp_encap_detach(ovar); 946 encap_lock_exit(); 947 948 if (osrc) 949 sockaddr_free(osrc); 950 if (odst) 951 sockaddr_free(odst); 952 kmem_free(ovar, sizeof(*ovar)); 953 954 return 0; 955 956 error: 957 sockaddr_free(nsrc); 958 sockaddr_free(ndst); 959 kmem_free(nvar, sizeof(*nvar)); 960 961 return error; 962 } 963 964 static void 965 l2tp_delete_tunnel(struct ifnet *ifp) 966 { 967 struct l2tp_softc *sc = container_of(ifp, struct l2tp_softc, 968 l2tp_ec.ec_if); 969 struct sockaddr *osrc, *odst; 970 struct l2tp_variant *ovar, *nvar; 971 int error; 972 973 nvar = kmem_alloc(sizeof(*nvar), KM_SLEEP); 974 975 error = encap_lock_enter(); 976 if (error) { 977 kmem_free(nvar, sizeof(*nvar)); 978 return; 979 } 980 mutex_enter(&sc->l2tp_lock); 981 982 ovar = sc->l2tp_var; 983 osrc = ovar->lv_psrc; 984 odst = ovar->lv_pdst; 985 *nvar = *ovar; 986 psref_target_init(&nvar->lv_psref, lv_psref_class); 987 nvar->lv_psrc = NULL; 988 nvar->lv_pdst = NULL; 989 membar_producer(); 990 l2tp_variant_update(sc, nvar); 991 992 mutex_exit(&sc->l2tp_lock); 993 994 (void)l2tp_encap_detach(ovar); 995 encap_lock_exit(); 996 997 if (osrc) 998 sockaddr_free(osrc); 999 if (odst) 1000 sockaddr_free(odst); 1001 kmem_free(ovar, sizeof(*ovar)); 1002 } 1003 1004 static int 1005 id_hash_func(uint32_t id, u_long mask) 1006 { 1007 uint32_t hash; 1008 1009 hash = (id >> 16) ^ id; 1010 hash = (hash >> 4) ^ hash; 1011 1012 return hash & mask; 1013 } 1014 1015 static void 1016 l2tp_hash_init(void) 1017 { 1018 1019 l2tp_hash.lists = hashinit(L2TP_ID_HASH_SIZE, HASH_PSLIST, true, 1020 &l2tp_hash.mask); 1021 } 1022 1023 static int 1024 l2tp_hash_fini(void) 1025 { 1026 int i; 1027 1028 mutex_enter(&l2tp_hash.lock); 1029 1030 for (i = 0; i < l2tp_hash.mask + 1; i++) { 1031 if (PSLIST_WRITER_FIRST(&l2tp_hash.lists[i], struct l2tp_softc, 1032 l2tp_hash) != NULL) { 1033 mutex_exit(&l2tp_hash.lock); 1034 return EBUSY; 1035 } 1036 } 1037 for (i = 0; i < l2tp_hash.mask + 1; i++) 1038 PSLIST_DESTROY(&l2tp_hash.lists[i]); 1039 1040 mutex_exit(&l2tp_hash.lock); 1041 1042 hashdone(l2tp_hash.lists, HASH_PSLIST, l2tp_hash.mask); 1043 1044 return 0; 1045 } 1046 1047 static int 1048 l2tp_set_session(struct l2tp_softc *sc, uint32_t my_sess_id, 1049 uint32_t peer_sess_id) 1050 { 1051 uint32_t idx; 1052 struct l2tp_variant *nvar; 1053 struct l2tp_variant *ovar; 1054 struct ifnet *ifp = &sc->l2tp_ec.ec_if; 1055 1056 nvar = kmem_alloc(sizeof(*nvar), KM_SLEEP); 1057 1058 mutex_enter(&sc->l2tp_lock); 1059 ovar = sc->l2tp_var; 1060 *nvar = *ovar; 1061 psref_target_init(&nvar->lv_psref, lv_psref_class); 1062 nvar->lv_my_sess_id = my_sess_id; 1063 nvar->lv_peer_sess_id = peer_sess_id; 1064 membar_producer(); 1065 1066 mutex_enter(&l2tp_hash.lock); 1067 if (ovar->lv_my_sess_id > 0 && ovar->lv_peer_sess_id > 0) { 1068 PSLIST_WRITER_REMOVE(sc, l2tp_hash); 1069 pserialize_perform(l2tp_psz); 1070 } 1071 mutex_exit(&l2tp_hash.lock); 1072 PSLIST_ENTRY_DESTROY(sc, l2tp_hash); 1073 1074 l2tp_variant_update(sc, nvar); 1075 mutex_exit(&sc->l2tp_lock); 1076 1077 idx = id_hash_func(nvar->lv_my_sess_id, l2tp_hash.mask); 1078 if ((ifp->if_flags & IFF_DEBUG) != 0) 1079 log(LOG_DEBUG, "%s: add hash entry: sess_id=%" PRIu32 ", idx=%" PRIu32 "\n", 1080 sc->l2tp_ec.ec_if.if_xname, nvar->lv_my_sess_id, idx); 1081 1082 PSLIST_ENTRY_INIT(sc, l2tp_hash); 1083 mutex_enter(&l2tp_hash.lock); 1084 PSLIST_WRITER_INSERT_HEAD(&l2tp_hash.lists[idx], sc, l2tp_hash); 1085 mutex_exit(&l2tp_hash.lock); 1086 1087 kmem_free(ovar, sizeof(*ovar)); 1088 return 0; 1089 } 1090 1091 static int 1092 l2tp_clear_session(struct l2tp_softc *sc) 1093 { 1094 struct l2tp_variant *nvar; 1095 struct l2tp_variant *ovar; 1096 1097 nvar = kmem_alloc(sizeof(*nvar), KM_SLEEP); 1098 1099 mutex_enter(&sc->l2tp_lock); 1100 ovar = sc->l2tp_var; 1101 *nvar = *ovar; 1102 psref_target_init(&nvar->lv_psref, lv_psref_class); 1103 nvar->lv_my_sess_id = 0; 1104 nvar->lv_peer_sess_id = 0; 1105 membar_producer(); 1106 1107 mutex_enter(&l2tp_hash.lock); 1108 if (ovar->lv_my_sess_id > 0 && ovar->lv_peer_sess_id > 0) { 1109 PSLIST_WRITER_REMOVE(sc, l2tp_hash); 1110 pserialize_perform(l2tp_psz); 1111 } 1112 mutex_exit(&l2tp_hash.lock); 1113 1114 l2tp_variant_update(sc, nvar); 1115 mutex_exit(&sc->l2tp_lock); 1116 kmem_free(ovar, sizeof(*ovar)); 1117 return 0; 1118 } 1119 1120 struct l2tp_variant * 1121 l2tp_lookup_session_ref(uint32_t id, struct psref *psref) 1122 { 1123 int idx; 1124 int s; 1125 struct l2tp_softc *sc; 1126 1127 idx = id_hash_func(id, l2tp_hash.mask); 1128 1129 s = pserialize_read_enter(); 1130 PSLIST_READER_FOREACH(sc, &l2tp_hash.lists[idx], struct l2tp_softc, 1131 l2tp_hash) { 1132 struct l2tp_variant *var = sc->l2tp_var; 1133 if (var == NULL) 1134 continue; 1135 if (var->lv_my_sess_id != id) 1136 continue; 1137 psref_acquire(psref, &var->lv_psref, lv_psref_class); 1138 pserialize_read_exit(s); 1139 return var; 1140 } 1141 pserialize_read_exit(s); 1142 return NULL; 1143 } 1144 1145 /* 1146 * l2tp_variant update API. 1147 * 1148 * Assumption: 1149 * reader side dereferences sc->l2tp_var in reader critical section only, 1150 * that is, all of reader sides do not reader the sc->l2tp_var after 1151 * pserialize_perform(). 1152 */ 1153 static void 1154 l2tp_variant_update(struct l2tp_softc *sc, struct l2tp_variant *nvar) 1155 { 1156 struct ifnet *ifp = &sc->l2tp_ec.ec_if; 1157 struct l2tp_variant *ovar = sc->l2tp_var; 1158 1159 KASSERT(mutex_owned(&sc->l2tp_lock)); 1160 1161 sc->l2tp_var = nvar; 1162 pserialize_perform(l2tp_psz); 1163 psref_target_destroy(&ovar->lv_psref, lv_psref_class); 1164 1165 /* 1166 * In the manual of atomic_swap_ptr(3), there is no mention if 2nd 1167 * argument is rewrite or not. So, use sc->l2tp_var instead of nvar. 1168 */ 1169 if (sc->l2tp_var != NULL) { 1170 if (sc->l2tp_var->lv_psrc != NULL 1171 && sc->l2tp_var->lv_pdst != NULL) 1172 ifp->if_flags |= IFF_RUNNING; 1173 else 1174 ifp->if_flags &= ~IFF_RUNNING; 1175 } 1176 } 1177 1178 static int 1179 l2tp_set_cookie(struct l2tp_softc *sc, uint64_t my_cookie, u_int my_cookie_len, 1180 uint64_t peer_cookie, u_int peer_cookie_len) 1181 { 1182 struct l2tp_variant *nvar; 1183 1184 if (my_cookie == 0 || peer_cookie == 0) 1185 return EINVAL; 1186 1187 if (my_cookie_len != 4 && my_cookie_len != 8 1188 && peer_cookie_len != 4 && peer_cookie_len != 8) 1189 return EINVAL; 1190 1191 nvar = kmem_alloc(sizeof(*nvar), KM_SLEEP); 1192 1193 mutex_enter(&sc->l2tp_lock); 1194 1195 *nvar = *sc->l2tp_var; 1196 psref_target_init(&nvar->lv_psref, lv_psref_class); 1197 nvar->lv_my_cookie = my_cookie; 1198 nvar->lv_my_cookie_len = my_cookie_len; 1199 nvar->lv_peer_cookie = peer_cookie; 1200 nvar->lv_peer_cookie_len = peer_cookie_len; 1201 nvar->lv_use_cookie = L2TP_COOKIE_ON; 1202 membar_producer(); 1203 l2tp_variant_update(sc, nvar); 1204 1205 mutex_exit(&sc->l2tp_lock); 1206 1207 struct ifnet *ifp = &sc->l2tp_ec.ec_if; 1208 if ((ifp->if_flags & IFF_DEBUG) != 0) { 1209 log(LOG_DEBUG, 1210 "%s: set cookie: " 1211 "local cookie_len=%u local cookie=%" PRIu64 ", " 1212 "remote cookie_len=%u remote cookie=%" PRIu64 "\n", 1213 ifp->if_xname, my_cookie_len, my_cookie, 1214 peer_cookie_len, peer_cookie); 1215 } 1216 1217 return 0; 1218 } 1219 1220 static void 1221 l2tp_clear_cookie(struct l2tp_softc *sc) 1222 { 1223 struct l2tp_variant *nvar; 1224 1225 nvar = kmem_alloc(sizeof(*nvar), KM_SLEEP); 1226 1227 mutex_enter(&sc->l2tp_lock); 1228 1229 *nvar = *sc->l2tp_var; 1230 psref_target_init(&nvar->lv_psref, lv_psref_class); 1231 nvar->lv_my_cookie = 0; 1232 nvar->lv_my_cookie_len = 0; 1233 nvar->lv_peer_cookie = 0; 1234 nvar->lv_peer_cookie_len = 0; 1235 nvar->lv_use_cookie = L2TP_COOKIE_OFF; 1236 membar_producer(); 1237 l2tp_variant_update(sc, nvar); 1238 1239 mutex_exit(&sc->l2tp_lock); 1240 } 1241 1242 static void 1243 l2tp_set_state(struct l2tp_softc *sc, int state) 1244 { 1245 struct ifnet *ifp = &sc->l2tp_ec.ec_if; 1246 struct l2tp_variant *nvar; 1247 1248 nvar = kmem_alloc(sizeof(*nvar), KM_SLEEP); 1249 1250 mutex_enter(&sc->l2tp_lock); 1251 1252 *nvar = *sc->l2tp_var; 1253 psref_target_init(&nvar->lv_psref, lv_psref_class); 1254 nvar->lv_state = state; 1255 membar_producer(); 1256 l2tp_variant_update(sc, nvar); 1257 1258 if (nvar->lv_state == L2TP_STATE_UP) { 1259 ifp->if_link_state = LINK_STATE_UP; 1260 } else { 1261 ifp->if_link_state = LINK_STATE_DOWN; 1262 } 1263 1264 mutex_exit(&sc->l2tp_lock); 1265 1266 #ifdef NOTYET 1267 vlan_linkstate_notify(ifp, ifp->if_link_state); 1268 #endif 1269 } 1270 1271 static int 1272 l2tp_encap_attach(struct l2tp_variant *var) 1273 { 1274 int error; 1275 1276 if (var == NULL || var->lv_psrc == NULL) 1277 return EINVAL; 1278 1279 switch (var->lv_psrc->sa_family) { 1280 #ifdef INET 1281 case AF_INET: 1282 error = in_l2tp_attach(var); 1283 break; 1284 #endif 1285 #ifdef INET6 1286 case AF_INET6: 1287 error = in6_l2tp_attach(var); 1288 break; 1289 #endif 1290 default: 1291 error = EINVAL; 1292 break; 1293 } 1294 1295 return error; 1296 } 1297 1298 static int 1299 l2tp_encap_detach(struct l2tp_variant *var) 1300 { 1301 int error; 1302 1303 if (var == NULL || var->lv_psrc == NULL) 1304 return EINVAL; 1305 1306 switch (var->lv_psrc->sa_family) { 1307 #ifdef INET 1308 case AF_INET: 1309 error = in_l2tp_detach(var); 1310 break; 1311 #endif 1312 #ifdef INET6 1313 case AF_INET6: 1314 error = in6_l2tp_detach(var); 1315 break; 1316 #endif 1317 default: 1318 error = EINVAL; 1319 break; 1320 } 1321 1322 return error; 1323 } 1324 1325 /* 1326 * TODO: 1327 * unify with gif_check_nesting(). 1328 */ 1329 int 1330 l2tp_check_nesting(struct ifnet *ifp, struct mbuf *m) 1331 { 1332 struct m_tag *mtag; 1333 int *count; 1334 1335 mtag = m_tag_find(m, PACKET_TAG_TUNNEL_INFO, NULL); 1336 if (mtag != NULL) { 1337 count = (int *)(mtag + 1); 1338 if (++(*count) > max_l2tp_nesting) { 1339 log(LOG_NOTICE, 1340 "%s: recursively called too many times(%d)\n", 1341 if_name(ifp), 1342 *count); 1343 return EIO; 1344 } 1345 } else { 1346 mtag = m_tag_get(PACKET_TAG_TUNNEL_INFO, sizeof(*count), 1347 M_NOWAIT); 1348 if (mtag != NULL) { 1349 m_tag_prepend(m, mtag); 1350 count = (int *)(mtag + 1); 1351 *count = 0; 1352 } 1353 #ifdef L2TP_DEBUG 1354 else { 1355 log(LOG_DEBUG, 1356 "%s: m_tag_get() failed, recursion calls are not prevented.\n", 1357 if_name(ifp)); 1358 } 1359 #endif 1360 } 1361 1362 return 0; 1363 } 1364 1365 /* 1366 * Module infrastructure 1367 */ 1368 #include "if_module.h" 1369 1370 IF_MODULE(MODULE_CLASS_DRIVER, l2tp, "") 1371 1372 1373 /* TODO: IP_TCPMSS support */ 1374 #ifdef IP_TCPMSS 1375 static int l2tp_need_tcpmss_clamp(struct ifnet *); 1376 #ifdef INET 1377 static struct mbuf *l2tp_tcpmss4_clamp(struct ifnet *, struct mbuf *); 1378 #endif 1379 #ifdef INET6 1380 static struct mbuf *l2tp_tcpmss6_clamp(struct ifnet *, struct mbuf *); 1381 #endif 1382 1383 struct mbuf * 1384 l2tp_tcpmss_clamp(struct ifnet *ifp, struct mbuf *m) 1385 { 1386 1387 if (l2tp_need_tcpmss_clamp(ifp)) { 1388 struct ether_header *eh; 1389 struct ether_vlan_header evh; 1390 1391 /* save ether header */ 1392 m_copydata(m, 0, sizeof(evh), (void *)&evh); 1393 eh = (struct ether_header *)&evh; 1394 1395 switch (ntohs(eh->ether_type)) { 1396 case ETHERTYPE_VLAN: /* Ether + VLAN */ 1397 if (m->m_pkthdr.len <= sizeof(struct ether_vlan_header)) 1398 break; 1399 m_adj(m, sizeof(struct ether_vlan_header)); 1400 switch (ntohs(evh.evl_proto)) { 1401 #ifdef INET 1402 case ETHERTYPE_IP: /* Ether + VLAN + IPv4 */ 1403 m = l2tp_tcpmss4_clamp(ifp, m); 1404 if (m == NULL) 1405 return NULL; 1406 break; 1407 #endif /* INET */ 1408 #ifdef INET6 1409 case ETHERTYPE_IPV6: /* Ether + VLAN + IPv6 */ 1410 m = l2tp_tcpmss6_clamp(ifp, m); 1411 if (m == NULL) 1412 return NULL; 1413 break; 1414 #endif /* INET6 */ 1415 default: 1416 break; 1417 } 1418 /* restore ether header */ 1419 M_PREPEND(m, sizeof(struct ether_vlan_header), 1420 M_DONTWAIT); 1421 if (m == NULL) 1422 return NULL; 1423 *mtod(m, struct ether_vlan_header *) = evh; 1424 break; 1425 #ifdef INET 1426 case ETHERTYPE_IP: /* Ether + IPv4 */ 1427 if (m->m_pkthdr.len <= sizeof(struct ether_header)) 1428 break; 1429 m_adj(m, sizeof(struct ether_header)); 1430 m = l2tp_tcpmss4_clamp(ifp, m); 1431 if (m == NULL) 1432 return NULL; 1433 /* restore ether header */ 1434 M_PREPEND(m, sizeof(struct ether_header), M_DONTWAIT); 1435 if (m == NULL) 1436 return NULL; 1437 *mtod(m, struct ether_header *) = *eh; 1438 break; 1439 #endif /* INET */ 1440 #ifdef INET6 1441 case ETHERTYPE_IPV6: /* Ether + IPv6 */ 1442 if (m->m_pkthdr.len <= sizeof(struct ether_header)) 1443 break; 1444 m_adj(m, sizeof(struct ether_header)); 1445 m = l2tp_tcpmss6_clamp(ifp, m); 1446 if (m == NULL) 1447 return NULL; 1448 /* restore ether header */ 1449 M_PREPEND(m, sizeof(struct ether_header), M_DONTWAIT); 1450 if (m == NULL) 1451 return NULL; 1452 *mtod(m, struct ether_header *) = *eh; 1453 break; 1454 #endif /* INET6 */ 1455 default: 1456 break; 1457 } 1458 } 1459 1460 return m; 1461 } 1462 1463 static int 1464 l2tp_need_tcpmss_clamp(struct ifnet *ifp) 1465 { 1466 int ret = 0; 1467 1468 #ifdef INET 1469 if (ifp->if_tcpmss != 0) 1470 ret = 1; 1471 #endif /* INET */ 1472 1473 #ifdef INET6 1474 if (ifp->if_tcpmss6 != 0) 1475 ret = 1; 1476 #endif /* INET6 */ 1477 1478 return ret; 1479 } 1480 1481 #ifdef INET 1482 static struct mbuf * 1483 l2tp_tcpmss4_clamp(struct ifnet *ifp, struct mbuf *m) 1484 { 1485 1486 if (ifp->if_tcpmss != 0) { 1487 return ip_tcpmss(m, (ifp->if_tcpmss < 0) ? 1488 ifp->if_mtu - IP_TCPMSS_EXTLEN : 1489 ifp->if_tcpmss); 1490 } 1491 return m; 1492 } 1493 #endif /* INET */ 1494 1495 #ifdef INET6 1496 static struct mbuf * 1497 l2tp_tcpmss6_clamp(struct ifnet *ifp, struct mbuf *m) 1498 { 1499 int ip6hdrlen; 1500 1501 if (ifp->if_tcpmss6 != 0 && 1502 ip6_tcpmss_applicable(m, &ip6hdrlen)) { 1503 return ip6_tcpmss(m, ip6hdrlen, 1504 (ifp->if_tcpmss6 < 0) ? 1505 ifp->if_mtu - IP6_TCPMSS_EXTLEN : 1506 ifp->if_tcpmss6); 1507 } 1508 return m; 1509 } 1510 #endif /* INET6 */ 1511 1512 #endif /* IP_TCPMSS */ 1513
Indexes created Fri Sep 26 20:09:58 GMT 2025