if_mpls.c revision 1.32
1 /* $NetBSD: if_mpls.c,v 1.32 2017/12/09 10:30:30 maxv Exp $ */ 2 3 /* 4 * Copyright (c) 2010 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Mihai Chelaru <kefren (at) NetBSD.org> 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: if_mpls.c,v 1.32 2017/12/09 10:30:30 maxv Exp $"); 34 35 #ifdef _KERNEL_OPT 36 #include "opt_inet.h" 37 #include "opt_mpls.h" 38 #endif 39 40 #include <sys/param.h> 41 42 #include <sys/errno.h> 43 #include <sys/malloc.h> 44 #include <sys/mbuf.h> 45 #include <sys/sysctl.h> 46 47 #include <net/bpf.h> 48 #include <net/if.h> 49 #include <net/if_types.h> 50 #include <net/netisr.h> 51 #include <net/route.h> 52 #include <sys/device.h> 53 #include <sys/module.h> 54 #include <sys/atomic.h> 55 56 #ifdef INET 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 #endif 63 64 #ifdef INET6 65 #include <netinet/ip6.h> 66 #include <netinet6/in6_var.h> 67 #include <netinet6/ip6_var.h> 68 #endif 69 70 #include <netmpls/mpls.h> 71 #include <netmpls/mpls_var.h> 72 73 #include "if_mpls.h" 74 75 #include "ioconf.h" 76 77 #define TRIM_LABEL do { \ 78 m_adj(m, sizeof(union mpls_shim)); \ 79 if (m->m_len < sizeof(union mpls_shim) && \ 80 (m = m_pullup(m, sizeof(union mpls_shim))) == NULL) \ 81 goto done; \ 82 dst.smpls_addr.s_addr = ntohl(mtod(m, union mpls_shim *)->s_addr); \ 83 } while (/* CONSTCOND */ 0) 84 85 86 static int mpls_clone_create(struct if_clone *, int); 87 static int mpls_clone_destroy(struct ifnet *); 88 89 static struct if_clone mpls_if_cloner = 90 IF_CLONE_INITIALIZER("mpls", mpls_clone_create, mpls_clone_destroy); 91 92 93 static void mpls_input(struct ifnet *, struct mbuf *); 94 static int mpls_output(struct ifnet *, struct mbuf *, const struct sockaddr *, 95 const struct rtentry *); 96 static int mpls_ioctl(struct ifnet *, u_long, void *); 97 static int mpls_send_frame(struct mbuf *, struct ifnet *, 98 const struct rtentry *); 99 static int mpls_lse(struct mbuf *); 100 101 #ifdef INET 102 static struct mbuf *mpls_unlabel_inet(struct mbuf *, int *error); 103 static struct mbuf *mpls_label_inet(struct mbuf *, union mpls_shim *, uint); 104 #endif 105 106 #ifdef INET6 107 static struct mbuf *mpls_unlabel_inet6(struct mbuf *, int *error); 108 static struct mbuf *mpls_label_inet6(struct mbuf *, union mpls_shim *, uint); 109 #endif 110 111 static struct mbuf *mpls_prepend_shim(struct mbuf *, union mpls_shim *); 112 113 extern int mpls_defttl, mpls_mapttl_inet, mpls_mapttl_inet6, mpls_icmp_respond, 114 mpls_forwarding, mpls_frame_accept, mpls_mapprec_inet, mpls_mapclass_inet6, 115 mpls_rfc4182; 116 117 static u_int mpls_count; 118 /* ARGSUSED */ 119 void 120 mplsattach(int count) 121 { 122 /* 123 * Nothing to do here, initialization is handled by the 124 * module initialization code in mplsinit() below). 125 */ 126 } 127 128 static void 129 mplsinit(void) 130 { 131 if_clone_attach(&mpls_if_cloner); 132 } 133 134 static int 135 mplsdetach(void) 136 { 137 int error = 0; 138 139 if (mpls_count != 0) 140 error = EBUSY; 141 142 if (error == 0) 143 if_clone_detach(&mpls_if_cloner); 144 145 return error; 146 } 147 148 static int 149 mpls_clone_create(struct if_clone *ifc, int unit) 150 { 151 struct mpls_softc *sc; 152 int rv; 153 154 atomic_inc_uint(&mpls_count); 155 sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK | M_ZERO); 156 157 if_initname(&sc->sc_if, ifc->ifc_name, unit); 158 sc->sc_if.if_softc = sc; 159 sc->sc_if.if_type = IFT_MPLS; 160 sc->sc_if.if_addrlen = 0; 161 sc->sc_if.if_hdrlen = sizeof(union mpls_shim); 162 sc->sc_if.if_dlt = DLT_NULL; 163 sc->sc_if.if_mtu = 1500; 164 sc->sc_if.if_flags = 0; 165 sc->sc_if._if_input = mpls_input; 166 sc->sc_if.if_output = mpls_output; 167 sc->sc_if.if_ioctl = mpls_ioctl; 168 169 rv = if_attach(&sc->sc_if); 170 if (rv != 0) { 171 free(sc, M_DEVBUF); 172 atomic_dec_uint(&mpls_count); 173 return rv; 174 } 175 if_alloc_sadl(&sc->sc_if); 176 bpf_attach(&sc->sc_if, DLT_NULL, sizeof(uint32_t)); 177 return 0; 178 } 179 180 static int 181 mpls_clone_destroy(struct ifnet *ifp) 182 { 183 int s; 184 185 bpf_detach(ifp); 186 187 s = splnet(); 188 if_detach(ifp); 189 splx(s); 190 191 free(ifp->if_softc, M_DEVBUF); 192 atomic_dec_uint(&mpls_count); 193 return 0; 194 } 195 196 static void 197 mpls_input(struct ifnet *ifp, struct mbuf *m) 198 { 199 #if 0 200 /* 201 * TODO - kefren 202 * I'd love to unshim the packet, guess family 203 * and pass it to bpf 204 */ 205 bpf_mtap_af(ifp, AF_MPLS, m); 206 #endif 207 208 mpls_lse(m); 209 } 210 211 void 212 mplsintr(void) 213 { 214 struct mbuf *m; 215 216 for (;;) { 217 IFQ_LOCK(&mplsintrq); 218 IF_DEQUEUE(&mplsintrq, m); 219 IFQ_UNLOCK(&mplsintrq); 220 221 if (!m) 222 return; 223 224 if (((m->m_flags & M_PKTHDR) == 0) || 225 (m->m_pkthdr.rcvif_index == 0)) 226 panic("mplsintr(): no pkthdr or rcvif"); 227 228 #ifdef MBUFTRACE 229 m_claimm(m, &mpls_owner); 230 #endif 231 mpls_input(m_get_rcvif_NOMPSAFE(m), m); 232 } 233 } 234 235 /* 236 * prepend shim and deliver 237 */ 238 static int 239 mpls_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 240 const struct rtentry *rt) 241 { 242 union mpls_shim mh, *pms; 243 struct rtentry *rt1; 244 int err; 245 uint psize = sizeof(struct sockaddr_mpls); 246 247 KASSERT(KERNEL_LOCKED_P()); 248 249 if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) { 250 m_freem(m); 251 return ENETDOWN; 252 } 253 254 if (rt_gettag(rt) == NULL || rt_gettag(rt)->sa_family != AF_MPLS) { 255 m_freem(m); 256 return EINVAL; 257 } 258 259 bpf_mtap_af(ifp, dst->sa_family, m); 260 261 memset(&mh, 0, sizeof(mh)); 262 mh.s_addr = MPLS_GETSADDR(rt); 263 mh.shim.bos = 1; 264 mh.shim.exp = 0; 265 mh.shim.ttl = mpls_defttl; 266 267 pms = &((struct sockaddr_mpls*)rt_gettag(rt))->smpls_addr; 268 269 while (psize <= rt_gettag(rt)->sa_len - sizeof(mh)) { 270 pms++; 271 if (mh.shim.label != MPLS_LABEL_IMPLNULL && 272 ((m = mpls_prepend_shim(m, &mh)) == NULL)) 273 return ENOBUFS; 274 memset(&mh, 0, sizeof(mh)); 275 mh.s_addr = ntohl(pms->s_addr); 276 mh.shim.bos = mh.shim.exp = 0; 277 mh.shim.ttl = mpls_defttl; 278 psize += sizeof(mh); 279 } 280 281 switch (dst->sa_family) { 282 #ifdef INET 283 case AF_INET: 284 m = mpls_label_inet(m, &mh, psize - sizeof(struct sockaddr_mpls)); 285 break; 286 #endif 287 #ifdef INET6 288 case AF_INET6: 289 m = mpls_label_inet6(m, &mh, psize - sizeof(struct sockaddr_mpls)); 290 break; 291 #endif 292 default: 293 m = mpls_prepend_shim(m, &mh); 294 break; 295 } 296 297 if (m == NULL) { 298 IF_DROP(&ifp->if_snd); 299 ifp->if_oerrors++; 300 return ENOBUFS; 301 } 302 303 ifp->if_opackets++; 304 ifp->if_obytes += m->m_pkthdr.len; 305 306 if ((rt1=rtalloc1(rt->rt_gateway, 1)) == NULL) { 307 m_freem(m); 308 return EHOSTUNREACH; 309 } 310 311 err = mpls_send_frame(m, rt1->rt_ifp, rt); 312 rt_unref(rt1); 313 return err; 314 } 315 316 static int 317 mpls_ioctl(struct ifnet *ifp, u_long cmd, void *data) 318 { 319 int error = 0, s = splnet(); 320 struct ifreq *ifr = data; 321 322 switch(cmd) { 323 case SIOCINITIFADDR: 324 ifp->if_flags |= IFF_UP | IFF_RUNNING; 325 break; 326 case SIOCSIFMTU: 327 if (ifr != NULL && ifr->ifr_mtu < 576) { 328 error = EINVAL; 329 break; 330 } 331 /* FALLTHROUGH */ 332 case SIOCGIFMTU: 333 if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET) 334 error = 0; 335 break; 336 case SIOCSIFFLAGS: 337 if ((error = ifioctl_common(ifp, cmd, data)) != 0) 338 break; 339 if (ifp->if_flags & IFF_UP) 340 ifp->if_flags |= IFF_RUNNING; 341 break; 342 default: 343 error = ifioctl_common(ifp, cmd, data); 344 break; 345 } 346 splx(s); 347 return error; 348 } 349 350 /* 351 * MPLS Label Switch Engine 352 */ 353 static int 354 mpls_lse(struct mbuf *m) 355 { 356 struct sockaddr_mpls dst; 357 union mpls_shim tshim, *htag; 358 struct rtentry *rt = NULL; 359 int error = ENOBUFS; 360 uint psize = sizeof(struct sockaddr_mpls); 361 bool push_back_alert = false; 362 363 /* If we're not accepting MPLS frames, leave now. */ 364 if (!mpls_frame_accept) { 365 error = EINVAL; 366 goto done; 367 } 368 369 if (m->m_len < sizeof(union mpls_shim) && 370 (m = m_pullup(m, sizeof(union mpls_shim))) == NULL) 371 goto done; 372 373 dst.smpls_len = sizeof(struct sockaddr_mpls); 374 dst.smpls_family = AF_MPLS; 375 dst.smpls_addr.s_addr = ntohl(mtod(m, union mpls_shim *)->s_addr); 376 377 error = EINVAL; 378 379 /* TTL decrement */ 380 if ((m = mpls_ttl_dec(m)) == NULL) 381 goto done; 382 383 /* RFC 4182 */ 384 if (mpls_rfc4182 != 0) { 385 while ((dst.smpls_addr.shim.label == MPLS_LABEL_IPV4NULL || 386 dst.smpls_addr.shim.label == MPLS_LABEL_IPV6NULL) && 387 __predict_false(dst.smpls_addr.shim.bos == 0)) 388 TRIM_LABEL; 389 } 390 391 /* RFC 3032 Section 2.1 Page 4 */ 392 if (__predict_false(dst.smpls_addr.shim.label == MPLS_LABEL_RTALERT) && 393 dst.smpls_addr.shim.bos == 0) { 394 TRIM_LABEL; 395 push_back_alert = true; 396 } 397 398 if (dst.smpls_addr.shim.label <= MPLS_LABEL_RESMAX) { 399 /* Don't swap reserved labels */ 400 switch (dst.smpls_addr.shim.label) { 401 #ifdef INET 402 case MPLS_LABEL_IPV4NULL: 403 /* Pop shim and push mbuf to IP stack */ 404 if (dst.smpls_addr.shim.bos) { 405 m = mpls_unlabel_inet(m, &error); 406 } 407 break; 408 #endif 409 #ifdef INET6 410 case MPLS_LABEL_IPV6NULL: 411 /* Pop shim and push mbuf to IPv6 stack */ 412 if (dst.smpls_addr.shim.bos) { 413 m = mpls_unlabel_inet6(m, &error); 414 } 415 break; 416 #endif 417 case MPLS_LABEL_RTALERT: /* Yeah, I'm all alerted */ 418 case MPLS_LABEL_IMPLNULL: /* This is logical only */ 419 default: /* Rest are not allowed */ 420 break; 421 } 422 goto done; 423 } 424 425 /* Check if we should do MPLS forwarding */ 426 error = EHOSTUNREACH; 427 if (!mpls_forwarding) 428 goto done; 429 430 /* Get a route to dst */ 431 dst.smpls_addr.shim.ttl = 432 dst.smpls_addr.shim.bos = 433 dst.smpls_addr.shim.exp = 0; 434 dst.smpls_addr.s_addr = htonl(dst.smpls_addr.s_addr); 435 if ((rt = rtalloc1((const struct sockaddr*)&dst, 1)) == NULL) 436 goto done; 437 438 /* MPLS packet with no MPLS tagged route ? */ 439 if ((rt->rt_flags & RTF_GATEWAY) == 0 || 440 rt_gettag(rt) == NULL || 441 rt_gettag(rt)->sa_family != AF_MPLS) 442 goto done; 443 444 tshim.s_addr = MPLS_GETSADDR(rt); 445 446 /* Swap labels */ 447 if ((m->m_len < sizeof(union mpls_shim)) && 448 (m = m_pullup(m, sizeof(union mpls_shim))) == 0) { 449 error = ENOBUFS; 450 goto done; 451 } 452 453 /* Replace only the label */ 454 htag = mtod(m, union mpls_shim *); 455 htag->s_addr = ntohl(htag->s_addr); 456 htag->shim.label = tshim.shim.label; 457 htag->s_addr = htonl(htag->s_addr); 458 459 /* check if there is anything more to prepend */ 460 htag = &((struct sockaddr_mpls*)rt_gettag(rt))->smpls_addr; 461 while (psize <= rt_gettag(rt)->sa_len - sizeof(tshim)) { 462 htag++; 463 memset(&tshim, 0, sizeof(tshim)); 464 tshim.s_addr = ntohl(htag->s_addr); 465 tshim.shim.bos = tshim.shim.exp = 0; 466 tshim.shim.ttl = mpls_defttl; 467 if (tshim.shim.label != MPLS_LABEL_IMPLNULL && 468 ((m = mpls_prepend_shim(m, &tshim)) == NULL)) { 469 error = ENOBUFS; 470 goto done; 471 } 472 psize += sizeof(tshim); 473 } 474 475 if (__predict_false(push_back_alert == true)) { 476 /* re-add the router alert label */ 477 memset(&tshim, 0, sizeof(tshim)); 478 tshim.s_addr = MPLS_LABEL_RTALERT; 479 tshim.shim.bos = tshim.shim.exp = 0; 480 tshim.shim.ttl = mpls_defttl; 481 if ((m = mpls_prepend_shim(m, &tshim)) == NULL) { 482 error = ENOBUFS; 483 goto done; 484 } 485 } 486 487 if ((rt->rt_flags & RTF_GATEWAY) == 0) { 488 error = EHOSTUNREACH; 489 goto done; 490 } 491 492 rt->rt_use++; 493 error = mpls_send_frame(m, rt->rt_ifp, rt); 494 495 done: 496 if (error != 0 && m != NULL) 497 m_freem(m); 498 if (rt != NULL) 499 rt_unref(rt); 500 501 return error; 502 } 503 504 static int 505 mpls_send_frame(struct mbuf *m, struct ifnet *ifp, const struct rtentry *rt) 506 { 507 union mpls_shim msh; 508 int ret; 509 510 msh.s_addr = MPLS_GETSADDR(rt); 511 if (msh.shim.label == MPLS_LABEL_IMPLNULL || 512 (m->m_flags & (M_MCAST | M_BCAST))) { 513 m_adj(m, sizeof(union mpls_shim)); 514 m->m_pkthdr.csum_flags = 0; 515 } 516 517 switch(ifp->if_type) { 518 /* only these are supported for now */ 519 case IFT_ETHER: 520 case IFT_TUNNEL: 521 case IFT_LOOP: 522 #ifdef INET 523 ret = ip_if_output(ifp, m, rt->rt_gateway, rt); 524 #else 525 ret = if_output_lock(ifp, ifp, m, rt->rt_gateway, rt); 526 #endif 527 return ret; 528 break; 529 default: 530 return ENETUNREACH; 531 } 532 return 0; 533 } 534 535 #ifdef INET 536 static struct mbuf * 537 mpls_unlabel_inet(struct mbuf *m, int *error) 538 { 539 struct ip *iph; 540 union mpls_shim *ms; 541 int iphlen; 542 543 if (mpls_mapttl_inet || mpls_mapprec_inet) { 544 /* get shim info */ 545 ms = mtod(m, union mpls_shim *); 546 ms->s_addr = ntohl(ms->s_addr); 547 548 /* and get rid of it */ 549 m_adj(m, sizeof(union mpls_shim)); 550 551 /* get ip header */ 552 if (m->m_len < sizeof(struct ip) && 553 (m = m_pullup(m, sizeof(struct ip))) == NULL) { 554 *error = ENOBUFS; 555 return NULL; 556 } 557 558 iph = mtod(m, struct ip *); 559 iphlen = iph->ip_hl << 2; 560 561 /* get it all */ 562 if (m->m_len < iphlen) { 563 if ((m = m_pullup(m, iphlen)) == NULL) { 564 *error = ENOBUFS; 565 return NULL; 566 } 567 iph = mtod(m, struct ip *); 568 } 569 570 /* check ipsum */ 571 if (in_cksum(m, iphlen) != 0) { 572 m_freem(m); 573 *error = EINVAL; 574 return NULL; 575 } 576 577 /* set IP ttl from MPLS ttl */ 578 if (mpls_mapttl_inet) 579 iph->ip_ttl = ms->shim.ttl; 580 581 /* set IP Precedence from MPLS Exp */ 582 if (mpls_mapprec_inet) { 583 iph->ip_tos = (iph->ip_tos << 3) >> 3; 584 iph->ip_tos |= ms->shim.exp << 5; 585 } 586 587 /* reset ipsum because we modified TTL and TOS */ 588 iph->ip_sum = 0; 589 iph->ip_sum = in_cksum(m, iphlen); 590 } else { 591 m_adj(m, sizeof(union mpls_shim)); 592 } 593 594 /* Put it on IP queue */ 595 if (__predict_false(!pktq_enqueue(ip_pktq, m, 0))) { 596 m_freem(m); 597 *error = ENOBUFS; 598 return NULL; 599 } 600 601 *error = 0; 602 return m; 603 } 604 605 /* 606 * Prepend MPLS label 607 */ 608 static struct mbuf * 609 mpls_label_inet(struct mbuf *m, union mpls_shim *ms, uint offset) 610 { 611 struct ip iphdr; 612 613 if (mpls_mapttl_inet || mpls_mapprec_inet) { 614 if ((m->m_len < sizeof(struct ip)) && 615 (m = m_pullup(m, offset + sizeof(struct ip))) == 0) 616 return NULL; /* XXX */ 617 m_copydata(m, offset, sizeof(struct ip), &iphdr); 618 619 /* Map TTL */ 620 if (mpls_mapttl_inet) 621 ms->shim.ttl = iphdr.ip_ttl; 622 623 /* Copy IP precedence to EXP */ 624 if (mpls_mapprec_inet) 625 ms->shim.exp = ((u_int8_t)iphdr.ip_tos) >> 5; 626 } 627 628 if ((m = mpls_prepend_shim(m, ms)) == NULL) 629 return NULL; 630 631 return m; 632 } 633 #endif /* INET */ 634 635 #ifdef INET6 636 static struct mbuf * 637 mpls_unlabel_inet6(struct mbuf *m, int *error) 638 { 639 struct ip6_hdr *ip6hdr; 640 union mpls_shim ms; 641 642 /* TODO: mapclass */ 643 if (mpls_mapttl_inet6) { 644 ms.s_addr = ntohl(mtod(m, union mpls_shim *)->s_addr); 645 m_adj(m, sizeof(union mpls_shim)); 646 647 if (m->m_len < sizeof(struct ip6_hdr) && 648 (m = m_pullup(m, sizeof(struct ip6_hdr))) == 0) { 649 *error = ENOBUFS; 650 return NULL; 651 } 652 ip6hdr = mtod(m, struct ip6_hdr *); 653 654 /* Because we just decremented this in mpls_lse */ 655 ip6hdr->ip6_hlim = ms.shim.ttl + 1; 656 } else { 657 m_adj(m, sizeof(union mpls_shim)); 658 } 659 660 /* Put it back on IPv6 queue. */ 661 if (__predict_false(!pktq_enqueue(ip6_pktq, m, 0))) { 662 m_freem(m); 663 *error = ENOBUFS; 664 return NULL; 665 } 666 667 *error = 0; 668 return m; 669 } 670 671 static struct mbuf * 672 mpls_label_inet6(struct mbuf *m, union mpls_shim *ms, uint offset) 673 { 674 struct ip6_hdr ip6h; 675 676 if (mpls_mapttl_inet6 || mpls_mapclass_inet6) { 677 if (m->m_len < sizeof(struct ip6_hdr) && 678 (m = m_pullup(m, offset + sizeof(struct ip6_hdr))) == 0) 679 return NULL; 680 m_copydata(m, offset, sizeof(struct ip6_hdr), &ip6h); 681 682 if (mpls_mapttl_inet6) 683 ms->shim.ttl = ip6h.ip6_hlim; 684 685 if (mpls_mapclass_inet6) 686 ms->shim.exp = ip6h.ip6_vfc << 1 >> 5; 687 } 688 689 if ((m = mpls_prepend_shim(m, ms)) == NULL) 690 return NULL; 691 692 return m; 693 } 694 #endif /* INET6 */ 695 696 static struct mbuf * 697 mpls_prepend_shim(struct mbuf *m, union mpls_shim *ms) 698 { 699 union mpls_shim *shim; 700 701 M_PREPEND(m, sizeof(*ms), M_DONTWAIT); 702 if (m == NULL) 703 return NULL; 704 705 if (m->m_len < sizeof(union mpls_shim) && 706 (m = m_pullup(m, sizeof(union mpls_shim))) == 0) 707 return NULL; 708 709 shim = mtod(m, union mpls_shim *); 710 711 memcpy(shim, ms, sizeof(*shim)); 712 shim->s_addr = htonl(shim->s_addr); 713 714 return m; 715 } 716 717 /* 718 * Module infrastructure 719 */ 720 #include "if_module.h" 721 722 IF_MODULE(MODULE_CLASS_DRIVER, mpls, "") 723
Indexes created Sun Sep 28 16:09:52 GMT 2025