1 /* $FreeBSD$ */ 2 /* $KAME: if_gif.c,v 1.47 2001/05/01 05:28:42 itojun Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include "opt_inet.h" 34 #include "opt_inet6.h" 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/kernel.h> 39 #include <sys/malloc.h> 40 #include <sys/mbuf.h> 41 #include <sys/socket.h> 42 #include <sys/sockio.h> 43 #include <sys/errno.h> 44 #include <sys/time.h> 45 #include <sys/syslog.h> 46 #include <sys/protosw.h> 47 #include <machine/cpu.h> 48 49 #include <net/if.h> 50 #include <net/if_types.h> 51 #include <net/netisr.h> 52 #include <net/route.h> 53 #include <net/bpf.h> 54 55 #include <netinet/in.h> 56 #include <netinet/in_systm.h> 57 #include <netinet/ip.h> 58 #ifdef INET 59 #include <netinet/in_var.h> 60 #include <netinet/in_gif.h> 61 #endif /* INET */ 62 63 #ifdef INET6 64 #ifndef INET 65 #include <netinet/in.h> 66 #endif 67 #include <netinet6/in6_var.h> 68 #include <netinet/ip6.h> 69 #include <netinet6/ip6_var.h> 70 #include <netinet6/in6_gif.h> 71 #include <netinet6/ip6protosw.h> 72 #endif /* INET6 */ 73 74 #include <netinet/ip_encap.h> 75 #include <net/if_gif.h> 76 77 #include "gif.h" 78 #include "bpf.h" 79 #define NBPFILTER NBPF 80 81 #include <net/net_osdep.h> 82 83 #if NGIF > 0 84 85 void gifattach __P((void *)); 86 static int gif_encapcheck __P((const struct mbuf *, int, int, void *)); 87 #ifdef INET 88 extern struct protosw in_gif_protosw; 89 #endif 90 #ifdef INET6 91 extern struct ip6protosw in6_gif_protosw; 92 #endif 93 94 /* 95 * gif global variable definitions 96 */ 97 static int ngif; /* number of interfaces */ 98 static struct gif_softc *gif = 0; 99 100 #ifndef MAX_GIF_NEST 101 /* 102 * This macro controls the upper limitation on nesting of gif tunnels. 103 * Since, setting a large value to this macro with a careless configuration 104 * may introduce system crash, we don't allow any nestings by default. 105 * If you need to configure nested gif tunnels, you can define this macro 106 * in your kernel configuration file. However, if you do so, please be 107 * careful to configure the tunnels so that it won't make a loop. 108 */ 109 #define MAX_GIF_NEST 1 110 #endif 111 static int max_gif_nesting = MAX_GIF_NEST; 112 113 void 114 gifattach(dummy) 115 void *dummy; 116 { 117 struct gif_softc *sc; 118 int i; 119 120 ngif = NGIF; 121 gif = sc = malloc(ngif * sizeof(struct gif_softc), M_DEVBUF, M_WAITOK); 122 bzero(sc, ngif * sizeof(struct gif_softc)); 123 for (i = 0; i < ngif; sc++, i++) { 124 sc->gif_if.if_name = "gif"; 125 sc->gif_if.if_unit = i; 126 127 sc->encap_cookie4 = sc->encap_cookie6 = NULL; 128 #ifdef INET 129 sc->encap_cookie4 = encap_attach_func(AF_INET, -1, 130 gif_encapcheck, &in_gif_protosw, sc); 131 if (sc->encap_cookie4 == NULL) { 132 printf("%s: attach failed\n", if_name(&sc->gif_if)); 133 continue; 134 } 135 #endif 136 #ifdef INET6 137 sc->encap_cookie6 = encap_attach_func(AF_INET6, -1, 138 gif_encapcheck, (struct protosw *)&in6_gif_protosw, sc); 139 if (sc->encap_cookie6 == NULL) { 140 if (sc->encap_cookie4) { 141 encap_detach(sc->encap_cookie4); 142 sc->encap_cookie4 = NULL; 143 } 144 printf("%s: attach failed\n", if_name(&sc->gif_if)); 145 continue; 146 } 147 #endif 148 149 sc->gif_if.if_mtu = GIF_MTU; 150 sc->gif_if.if_flags = IFF_POINTOPOINT | IFF_MULTICAST; 151 #if 0 152 /* turn off ingress filter */ 153 sc->gif_if.if_flags |= IFF_LINK2; 154 #endif 155 sc->gif_if.if_ioctl = gif_ioctl; 156 sc->gif_if.if_output = gif_output; 157 sc->gif_if.if_type = IFT_GIF; 158 sc->gif_if.if_snd.ifq_maxlen = IFQ_MAXLEN; 159 if_attach(&sc->gif_if); 160 #if NBPFILTER > 0 161 #ifdef HAVE_OLD_BPF 162 bpfattach(&sc->gif_if, DLT_NULL, sizeof(u_int)); 163 #else 164 bpfattach(&sc->gif_if.if_bpf, &sc->gif_if, DLT_NULL, sizeof(u_int)); 165 #endif 166 #endif 167 } 168 } 169 170 PSEUDO_SET(gifattach, if_gif); 171 172 static int 173 gif_encapcheck(m, off, proto, arg) 174 const struct mbuf *m; 175 int off; 176 int proto; 177 void *arg; 178 { 179 struct ip ip; 180 struct gif_softc *sc; 181 182 sc = (struct gif_softc *)arg; 183 if (sc == NULL) 184 return 0; 185 186 if ((sc->gif_if.if_flags & IFF_UP) == 0) 187 return 0; 188 189 /* no physical address */ 190 if (!sc->gif_psrc || !sc->gif_pdst) 191 return 0; 192 193 switch (proto) { 194 #ifdef INET 195 case IPPROTO_IPV4: 196 break; 197 #endif 198 #ifdef INET6 199 case IPPROTO_IPV6: 200 break; 201 #endif 202 default: 203 return 0; 204 } 205 206 /* LINTED const cast */ 207 m_copydata((struct mbuf *)m, 0, sizeof(ip), (caddr_t)&ip); 208 209 switch (ip.ip_v) { 210 #ifdef INET 211 case 4: 212 if (sc->gif_psrc->sa_family != AF_INET || 213 sc->gif_pdst->sa_family != AF_INET) 214 return 0; 215 return gif_encapcheck4(m, off, proto, arg); 216 #endif 217 #ifdef INET6 218 case 6: 219 if (sc->gif_psrc->sa_family != AF_INET6 || 220 sc->gif_pdst->sa_family != AF_INET6) 221 return 0; 222 return gif_encapcheck6(m, off, proto, arg); 223 #endif 224 default: 225 return 0; 226 } 227 } 228 229 int 230 gif_output(ifp, m, dst, rt) 231 struct ifnet *ifp; 232 struct mbuf *m; 233 struct sockaddr *dst; 234 struct rtentry *rt; /* added in net2 */ 235 { 236 struct gif_softc *sc = (struct gif_softc*)ifp; 237 int error = 0; 238 static int called = 0; /* XXX: MUTEX */ 239 240 /* 241 * gif may cause infinite recursion calls when misconfigured. 242 * We'll prevent this by introducing upper limit. 243 * XXX: this mechanism may introduce another problem about 244 * mutual exclusion of the variable CALLED, especially if we 245 * use kernel thread. 246 */ 247 if (++called > max_gif_nesting) { 248 log(LOG_NOTICE, 249 "gif_output: recursively called too many times(%d)\n", 250 called); 251 m_freem(m); 252 error = EIO; /* is there better errno? */ 253 goto end; 254 } 255 256 m->m_flags &= ~(M_BCAST|M_MCAST); 257 if (!(ifp->if_flags & IFF_UP) || 258 sc->gif_psrc == NULL || sc->gif_pdst == NULL) { 259 m_freem(m); 260 error = ENETDOWN; 261 goto end; 262 } 263 264 #if NBPFILTER > 0 265 if (ifp->if_bpf) { 266 /* 267 * We need to prepend the address family as 268 * a four byte field. Cons up a dummy header 269 * to pacify bpf. This is safe because bpf 270 * will only read from the mbuf (i.e., it won't 271 * try to free it or keep a pointer a to it). 272 */ 273 struct mbuf m0; 274 u_int32_t af = dst->sa_family; 275 276 m0.m_next = m; 277 m0.m_len = 4; 278 m0.m_data = (char *)⁡ 279 280 #ifdef HAVE_OLD_BPF 281 bpf_mtap(ifp, &m0); 282 #else 283 bpf_mtap(ifp->if_bpf, &m0); 284 #endif 285 } 286 #endif 287 ifp->if_opackets++; 288 ifp->if_obytes += m->m_pkthdr.len; 289 290 /* inner AF-specific encapsulation */ 291 292 /* XXX should we check if our outer source is legal? */ 293 294 /* dispatch to output logic based on outer AF */ 295 switch (sc->gif_psrc->sa_family) { 296 #ifdef INET 297 case AF_INET: 298 error = in_gif_output(ifp, dst->sa_family, m, rt); 299 break; 300 #endif 301 #ifdef INET6 302 case AF_INET6: 303 error = in6_gif_output(ifp, dst->sa_family, m, rt); 304 break; 305 #endif 306 default: 307 m_freem(m); 308 error = ENETDOWN; 309 goto end; 310 } 311 312 end: 313 called = 0; /* reset recursion counter */ 314 if (error) 315 ifp->if_oerrors++; 316 return error; 317 } 318 319 void 320 gif_input(m, af, gifp) 321 struct mbuf *m; 322 int af; 323 struct ifnet *gifp; 324 { 325 int isr; 326 struct ifqueue *ifq = 0; 327 328 if (gifp == NULL) { 329 /* just in case */ 330 m_freem(m); 331 return; 332 } 333 334 m->m_pkthdr.rcvif = gifp; 335 336 #if NBPFILTER > 0 337 if (gifp->if_bpf) { 338 /* 339 * We need to prepend the address family as 340 * a four byte field. Cons up a dummy header 341 * to pacify bpf. This is safe because bpf 342 * will only read from the mbuf (i.e., it won't 343 * try to free it or keep a pointer a to it). 344 */ 345 struct mbuf m0; 346 u_int32_t af1 = af; 347 348 m0.m_next = m; 349 m0.m_len = 4; 350 m0.m_data = (char *)&af1; 351 352 #ifdef HAVE_OLD_BPF 353 bpf_mtap(gifp, &m0); 354 #else 355 bpf_mtap(gifp->if_bpf, &m0); 356 #endif 357 } 358 #endif /*NBPFILTER > 0*/ 359 360 /* 361 * Put the packet to the network layer input queue according to the 362 * specified address family. 363 * Note: older versions of gif_input directly called network layer 364 * input functions, e.g. ip6_input, here. We changed the policy to 365 * prevent too many recursive calls of such input functions, which 366 * might cause kernel panic. But the change may introduce another 367 * problem; if the input queue is full, packets are discarded. 368 * We believed it rarely occurs and changed the policy. If we find 369 * it occurs more times than we thought, we may change the policy 370 * again. 371 */ 372 switch (af) { 373 #ifdef INET 374 case AF_INET: 375 ifq = &ipintrq; 376 isr = NETISR_IP; 377 break; 378 #endif 379 #ifdef INET6 380 case AF_INET6: 381 ifq = &ip6intrq; 382 isr = NETISR_IPV6; 383 break; 384 #endif 385 default: 386 m_freem(m); 387 return; 388 } 389 390 gifp->if_ipackets++; 391 gifp->if_ibytes += m->m_pkthdr.len; 392 (void) IF_HANDOFF(ifq, m, NULL); 393 /* we need schednetisr since the address family may change */ 394 schednetisr(isr); 395 396 return; 397 } 398 399 /* XXX how should we handle IPv6 scope on SIOC[GS]IFPHYADDR? */ 400 int 401 gif_ioctl(ifp, cmd, data) 402 struct ifnet *ifp; 403 u_long cmd; 404 caddr_t data; 405 { 406 struct gif_softc *sc = (struct gif_softc*)ifp; 407 struct ifreq *ifr = (struct ifreq*)data; 408 int error = 0, size; 409 struct sockaddr *dst, *src; 410 struct sockaddr *sa; 411 int i; 412 int s; 413 struct gif_softc *sc2; 414 415 switch (cmd) { 416 case SIOCSIFADDR: 417 break; 418 419 case SIOCSIFDSTADDR: 420 break; 421 422 case SIOCADDMULTI: 423 case SIOCDELMULTI: 424 break; 425 426 #ifdef SIOCSIFMTU /* xxx */ 427 case SIOCGIFMTU: 428 break; 429 430 case SIOCSIFMTU: 431 { 432 u_long mtu; 433 mtu = ifr->ifr_mtu; 434 if (mtu < GIF_MTU_MIN || mtu > GIF_MTU_MAX) { 435 return (EINVAL); 436 } 437 ifp->if_mtu = mtu; 438 } 439 break; 440 #endif /* SIOCSIFMTU */ 441 442 case SIOCSIFPHYADDR: 443 #ifdef INET6 444 case SIOCSIFPHYADDR_IN6: 445 #endif /* INET6 */ 446 case SIOCSLIFPHYADDR: 447 switch (cmd) { 448 #ifdef INET 449 case SIOCSIFPHYADDR: 450 src = (struct sockaddr *) 451 &(((struct in_aliasreq *)data)->ifra_addr); 452 dst = (struct sockaddr *) 453 &(((struct in_aliasreq *)data)->ifra_dstaddr); 454 break; 455 #endif 456 #ifdef INET6 457 case SIOCSIFPHYADDR_IN6: 458 src = (struct sockaddr *) 459 &(((struct in6_aliasreq *)data)->ifra_addr); 460 dst = (struct sockaddr *) 461 &(((struct in6_aliasreq *)data)->ifra_dstaddr); 462 break; 463 #endif 464 case SIOCSLIFPHYADDR: 465 src = (struct sockaddr *) 466 &(((struct if_laddrreq *)data)->addr); 467 dst = (struct sockaddr *) 468 &(((struct if_laddrreq *)data)->dstaddr); 469 } 470 471 /* sa_family must be equal */ 472 if (src->sa_family != dst->sa_family) 473 return EINVAL; 474 475 /* validate sa_len */ 476 switch (src->sa_family) { 477 #ifdef INET 478 case AF_INET: 479 if (src->sa_len != sizeof(struct sockaddr_in)) 480 return EINVAL; 481 break; 482 #endif 483 #ifdef INET6 484 case AF_INET6: 485 if (src->sa_len != sizeof(struct sockaddr_in6)) 486 return EINVAL; 487 break; 488 #endif 489 default: 490 return EAFNOSUPPORT; 491 } 492 switch (dst->sa_family) { 493 #ifdef INET 494 case AF_INET: 495 if (dst->sa_len != sizeof(struct sockaddr_in)) 496 return EINVAL; 497 break; 498 #endif 499 #ifdef INET6 500 case AF_INET6: 501 if (dst->sa_len != sizeof(struct sockaddr_in6)) 502 return EINVAL; 503 break; 504 #endif 505 default: 506 return EAFNOSUPPORT; 507 } 508 509 /* check sa_family looks sane for the cmd */ 510 switch (cmd) { 511 case SIOCSIFPHYADDR: 512 if (src->sa_family == AF_INET) 513 break; 514 return EAFNOSUPPORT; 515 #ifdef INET6 516 case SIOCSIFPHYADDR_IN6: 517 if (src->sa_family == AF_INET6) 518 break; 519 return EAFNOSUPPORT; 520 #endif /* INET6 */ 521 case SIOCSLIFPHYADDR: 522 /* checks done in the above */ 523 break; 524 } 525 526 for (i = 0; i < ngif; i++) { 527 sc2 = gif + i; 528 if (sc2 == sc) 529 continue; 530 if (!sc2->gif_pdst || !sc2->gif_psrc) 531 continue; 532 if (sc2->gif_pdst->sa_family != dst->sa_family || 533 sc2->gif_pdst->sa_len != dst->sa_len || 534 sc2->gif_psrc->sa_family != src->sa_family || 535 sc2->gif_psrc->sa_len != src->sa_len) 536 continue; 537 #ifndef XBONEHACK 538 /* can't configure same pair of address onto two gifs */ 539 if (bcmp(sc2->gif_pdst, dst, dst->sa_len) == 0 && 540 bcmp(sc2->gif_psrc, src, src->sa_len) == 0) { 541 error = EADDRNOTAVAIL; 542 goto bad; 543 } 544 #endif 545 546 /* can't configure multiple multi-dest interfaces */ 547 #define multidest(x) \ 548 (((struct sockaddr_in *)(x))->sin_addr.s_addr == INADDR_ANY) 549 #ifdef INET6 550 #define multidest6(x) \ 551 (IN6_IS_ADDR_UNSPECIFIED(&((struct sockaddr_in6 *)(x))->sin6_addr)) 552 #endif 553 if (dst->sa_family == AF_INET && 554 multidest(dst) && multidest(sc2->gif_pdst)) { 555 error = EADDRNOTAVAIL; 556 goto bad; 557 } 558 #ifdef INET6 559 if (dst->sa_family == AF_INET6 && 560 multidest6(dst) && multidest6(sc2->gif_pdst)) { 561 error = EADDRNOTAVAIL; 562 goto bad; 563 } 564 #endif 565 } 566 567 if (sc->gif_psrc) 568 free((caddr_t)sc->gif_psrc, M_IFADDR); 569 sa = (struct sockaddr *)malloc(src->sa_len, M_IFADDR, M_WAITOK); 570 bcopy((caddr_t)src, (caddr_t)sa, src->sa_len); 571 sc->gif_psrc = sa; 572 573 if (sc->gif_pdst) 574 free((caddr_t)sc->gif_pdst, M_IFADDR); 575 sa = (struct sockaddr *)malloc(dst->sa_len, M_IFADDR, M_WAITOK); 576 bcopy((caddr_t)dst, (caddr_t)sa, dst->sa_len); 577 sc->gif_pdst = sa; 578 579 ifp->if_flags |= IFF_RUNNING; 580 s = splimp(); 581 if_up(ifp); /* mark interface UP and send up RTM_IFINFO */ 582 splx(s); 583 584 error = 0; 585 break; 586 587 #ifdef SIOCDIFPHYADDR 588 case SIOCDIFPHYADDR: 589 if (sc->gif_psrc) { 590 free((caddr_t)sc->gif_psrc, M_IFADDR); 591 sc->gif_psrc = NULL; 592 } 593 if (sc->gif_pdst) { 594 free((caddr_t)sc->gif_pdst, M_IFADDR); 595 sc->gif_pdst = NULL; 596 } 597 /* change the IFF_{UP, RUNNING} flag as well? */ 598 break; 599 #endif 600 601 case SIOCGIFPSRCADDR: 602 #ifdef INET6 603 case SIOCGIFPSRCADDR_IN6: 604 #endif /* INET6 */ 605 if (sc->gif_psrc == NULL) { 606 error = EADDRNOTAVAIL; 607 goto bad; 608 } 609 src = sc->gif_psrc; 610 switch (cmd) { 611 #ifdef INET 612 case SIOCGIFPSRCADDR: 613 dst = &ifr->ifr_addr; 614 size = sizeof(ifr->ifr_addr); 615 break; 616 #endif /* INET */ 617 #ifdef INET6 618 case SIOCGIFPSRCADDR_IN6: 619 dst = (struct sockaddr *) 620 &(((struct in6_ifreq *)data)->ifr_addr); 621 size = sizeof(((struct in6_ifreq *)data)->ifr_addr); 622 break; 623 #endif /* INET6 */ 624 default: 625 error = EADDRNOTAVAIL; 626 goto bad; 627 } 628 if (src->sa_len > size) 629 return EINVAL; 630 bcopy((caddr_t)src, (caddr_t)dst, src->sa_len); 631 break; 632 633 case SIOCGIFPDSTADDR: 634 #ifdef INET6 635 case SIOCGIFPDSTADDR_IN6: 636 #endif /* INET6 */ 637 if (sc->gif_pdst == NULL) { 638 error = EADDRNOTAVAIL; 639 goto bad; 640 } 641 src = sc->gif_pdst; 642 switch (cmd) { 643 #ifdef INET 644 case SIOCGIFPDSTADDR: 645 dst = &ifr->ifr_addr; 646 size = sizeof(ifr->ifr_addr); 647 break; 648 #endif /* INET */ 649 #ifdef INET6 650 case SIOCGIFPDSTADDR_IN6: 651 dst = (struct sockaddr *) 652 &(((struct in6_ifreq *)data)->ifr_addr); 653 size = sizeof(((struct in6_ifreq *)data)->ifr_addr); 654 break; 655 #endif /* INET6 */ 656 default: 657 error = EADDRNOTAVAIL; 658 goto bad; 659 } 660 if (src->sa_len > size) 661 return EINVAL; 662 bcopy((caddr_t)src, (caddr_t)dst, src->sa_len); 663 break; 664 665 case SIOCGLIFPHYADDR: 666 if (sc->gif_psrc == NULL || sc->gif_pdst == NULL) { 667 error = EADDRNOTAVAIL; 668 goto bad; 669 } 670 671 /* copy src */ 672 src = sc->gif_psrc; 673 dst = (struct sockaddr *) 674 &(((struct if_laddrreq *)data)->addr); 675 size = sizeof(((struct if_laddrreq *)data)->addr); 676 if (src->sa_len > size) 677 return EINVAL; 678 bcopy((caddr_t)src, (caddr_t)dst, src->sa_len); 679 680 /* copy dst */ 681 src = sc->gif_pdst; 682 dst = (struct sockaddr *) 683 &(((struct if_laddrreq *)data)->dstaddr); 684 size = sizeof(((struct if_laddrreq *)data)->dstaddr); 685 if (src->sa_len > size) 686 return EINVAL; 687 bcopy((caddr_t)src, (caddr_t)dst, src->sa_len); 688 break; 689 690 case SIOCSIFFLAGS: 691 /* if_ioctl() takes care of it */ 692 break; 693 694 default: 695 error = EINVAL; 696 break; 697 } 698 bad: 699 return error; 700 } 701 #endif /*NGIF > 0*/ 702