1 /* $NetBSD: if_tun.c,v 1.127 2016/07/07 09:32:02 ozaki-r Exp $ */ 2 3 /* 4 * Copyright (c) 1988, Julian Onions <jpo@cs.nott.ac.uk> 5 * Nottingham University 1987. 6 * 7 * This source may be freely distributed, however I would be interested 8 * in any changes that are made. 9 * 10 * This driver takes packets off the IP i/f and hands them up to a 11 * user process to have its wicked way with. This driver has its 12 * roots in a similar driver written by Phil Cockcroft (formerly) at 13 * UCL. This driver is based much more on read/write/poll mode of 14 * operation though. 15 */ 16 17 #include <sys/cdefs.h> 18 __KERNEL_RCSID(0, "$NetBSD: if_tun.c,v 1.127 2016/07/07 09:32:02 ozaki-r Exp $"); 19 20 #ifdef _KERNEL_OPT 21 #include "opt_inet.h" 22 #endif 23 24 #include <sys/param.h> 25 #include <sys/proc.h> 26 #include <sys/systm.h> 27 #include <sys/mbuf.h> 28 #include <sys/buf.h> 29 #include <sys/protosw.h> 30 #include <sys/socket.h> 31 #include <sys/ioctl.h> 32 #include <sys/errno.h> 33 #include <sys/syslog.h> 34 #include <sys/select.h> 35 #include <sys/poll.h> 36 #include <sys/file.h> 37 #include <sys/signalvar.h> 38 #include <sys/conf.h> 39 #include <sys/kauth.h> 40 #include <sys/mutex.h> 41 #include <sys/cpu.h> 42 43 #include <net/if.h> 44 #include <net/if_types.h> 45 #include <net/netisr.h> 46 #include <net/route.h> 47 48 49 #ifdef INET 50 #include <netinet/in.h> 51 #include <netinet/in_systm.h> 52 #include <netinet/in_var.h> 53 #include <netinet/ip.h> 54 #include <netinet/if_inarp.h> 55 #endif 56 57 58 #include <sys/time.h> 59 #include <net/bpf.h> 60 61 #include <net/if_tun.h> 62 63 #include "ioconf.h" 64 65 #define TUNDEBUG if (tundebug) printf 66 int tundebug = 0; 67 68 extern int ifqmaxlen; 69 70 static LIST_HEAD(, tun_softc) tun_softc_list; 71 static LIST_HEAD(, tun_softc) tunz_softc_list; 72 static kmutex_t tun_softc_lock; 73 74 static int tun_ioctl(struct ifnet *, u_long, void *); 75 static int tun_output(struct ifnet *, struct mbuf *, 76 const struct sockaddr *, const struct rtentry *rt); 77 static int tun_clone_create(struct if_clone *, int); 78 static int tun_clone_destroy(struct ifnet *); 79 80 static struct if_clone tun_cloner = 81 IF_CLONE_INITIALIZER("tun", tun_clone_create, tun_clone_destroy); 82 83 static void tunattach0(struct tun_softc *); 84 static void tuninit(struct tun_softc *); 85 static void tun_i_softintr(void *); 86 static void tun_o_softintr(void *); 87 #ifdef ALTQ 88 static void tunstart(struct ifnet *); 89 #endif 90 static struct tun_softc *tun_find_unit(dev_t); 91 static struct tun_softc *tun_find_zunit(int); 92 93 static dev_type_open(tunopen); 94 static dev_type_close(tunclose); 95 static dev_type_read(tunread); 96 static dev_type_write(tunwrite); 97 static dev_type_ioctl(tunioctl); 98 static dev_type_poll(tunpoll); 99 static dev_type_kqfilter(tunkqfilter); 100 101 const struct cdevsw tun_cdevsw = { 102 .d_open = tunopen, 103 .d_close = tunclose, 104 .d_read = tunread, 105 .d_write = tunwrite, 106 .d_ioctl = tunioctl, 107 .d_stop = nostop, 108 .d_tty = notty, 109 .d_poll = tunpoll, 110 .d_mmap = nommap, 111 .d_kqfilter = tunkqfilter, 112 .d_discard = nodiscard, 113 .d_flag = D_OTHER 114 }; 115 116 void 117 tunattach(int unused) 118 { 119 120 mutex_init(&tun_softc_lock, MUTEX_DEFAULT, IPL_NET); 121 LIST_INIT(&tun_softc_list); 122 LIST_INIT(&tunz_softc_list); 123 if_clone_attach(&tun_cloner); 124 } 125 126 /* 127 * Find driver instance from dev_t. 128 * Returns with tp locked (if found). 129 */ 130 static struct tun_softc * 131 tun_find_unit(dev_t dev) 132 { 133 struct tun_softc *tp; 134 int unit = minor(dev); 135 136 mutex_enter(&tun_softc_lock); 137 LIST_FOREACH(tp, &tun_softc_list, tun_list) 138 if (unit == tp->tun_unit) 139 break; 140 if (tp) 141 mutex_enter(&tp->tun_lock); 142 mutex_exit(&tun_softc_lock); 143 144 return (tp); 145 } 146 147 /* 148 * Find zombie driver instance by unit number. 149 * Remove tp from list and return it unlocked (if found). 150 */ 151 static struct tun_softc * 152 tun_find_zunit(int unit) 153 { 154 struct tun_softc *tp; 155 156 mutex_enter(&tun_softc_lock); 157 LIST_FOREACH(tp, &tunz_softc_list, tun_list) 158 if (unit == tp->tun_unit) 159 break; 160 if (tp) 161 LIST_REMOVE(tp, tun_list); 162 mutex_exit(&tun_softc_lock); 163 #ifdef DIAGNOSTIC 164 if (tp != NULL && (tp->tun_flags & (TUN_INITED|TUN_OPEN)) != TUN_OPEN) 165 printf("tun%d: inconsistent flags: %x\n", unit, tp->tun_flags); 166 #endif 167 168 return (tp); 169 } 170 171 static int 172 tun_clone_create(struct if_clone *ifc, int unit) 173 { 174 struct tun_softc *tp; 175 176 if ((tp = tun_find_zunit(unit)) == NULL) { 177 /* Allocate a new instance */ 178 tp = malloc(sizeof(*tp), M_DEVBUF, M_WAITOK|M_ZERO); 179 180 tp->tun_unit = unit; 181 mutex_init(&tp->tun_lock, MUTEX_DEFAULT, IPL_NET); 182 selinit(&tp->tun_rsel); 183 selinit(&tp->tun_wsel); 184 } else { 185 /* Revive tunnel instance; clear ifp part */ 186 (void)memset(&tp->tun_if, 0, sizeof(struct ifnet)); 187 } 188 189 if_initname(&tp->tun_if, ifc->ifc_name, unit); 190 tunattach0(tp); 191 tp->tun_flags |= TUN_INITED; 192 tp->tun_osih = softint_establish(SOFTINT_CLOCK, tun_o_softintr, tp); 193 tp->tun_isih = softint_establish(SOFTINT_CLOCK, tun_i_softintr, tp); 194 195 mutex_enter(&tun_softc_lock); 196 LIST_INSERT_HEAD(&tun_softc_list, tp, tun_list); 197 mutex_exit(&tun_softc_lock); 198 199 return (0); 200 } 201 202 static void 203 tunattach0(struct tun_softc *tp) 204 { 205 struct ifnet *ifp; 206 207 ifp = &tp->tun_if; 208 ifp->if_softc = tp; 209 ifp->if_mtu = TUNMTU; 210 ifp->if_ioctl = tun_ioctl; 211 ifp->if_output = tun_output; 212 #ifdef ALTQ 213 ifp->if_start = tunstart; 214 #endif 215 ifp->if_flags = IFF_POINTOPOINT; 216 ifp->if_type = IFT_TUNNEL; 217 ifp->if_snd.ifq_maxlen = ifqmaxlen; 218 ifp->if_collisions = 0; 219 ifp->if_ierrors = 0; 220 ifp->if_oerrors = 0; 221 ifp->if_ipackets = 0; 222 ifp->if_opackets = 0; 223 ifp->if_ibytes = 0; 224 ifp->if_obytes = 0; 225 ifp->if_dlt = DLT_NULL; 226 IFQ_SET_READY(&ifp->if_snd); 227 if_attach(ifp); 228 if_alloc_sadl(ifp); 229 bpf_attach(ifp, DLT_NULL, sizeof(uint32_t)); 230 } 231 232 static int 233 tun_clone_destroy(struct ifnet *ifp) 234 { 235 struct tun_softc *tp = (void *)ifp; 236 int zombie = 0; 237 238 IF_PURGE(&ifp->if_snd); 239 ifp->if_flags &= ~IFF_RUNNING; 240 241 mutex_enter(&tun_softc_lock); 242 mutex_enter(&tp->tun_lock); 243 LIST_REMOVE(tp, tun_list); 244 if (tp->tun_flags & TUN_OPEN) { 245 /* Hang on to storage until last close */ 246 zombie = 1; 247 tp->tun_flags &= ~TUN_INITED; 248 LIST_INSERT_HEAD(&tunz_softc_list, tp, tun_list); 249 } 250 mutex_exit(&tun_softc_lock); 251 252 if (tp->tun_flags & TUN_RWAIT) { 253 tp->tun_flags &= ~TUN_RWAIT; 254 wakeup((void *)tp); 255 } 256 selnotify(&tp->tun_rsel, 0, 0); 257 258 mutex_exit(&tp->tun_lock); 259 260 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 261 fownsignal(tp->tun_pgid, SIGIO, POLL_HUP, 0, NULL); 262 263 bpf_detach(ifp); 264 if_detach(ifp); 265 266 if (!zombie) { 267 seldestroy(&tp->tun_rsel); 268 seldestroy(&tp->tun_wsel); 269 softint_disestablish(tp->tun_osih); 270 softint_disestablish(tp->tun_isih); 271 mutex_destroy(&tp->tun_lock); 272 free(tp, M_DEVBUF); 273 } 274 275 return (0); 276 } 277 278 /* 279 * tunnel open - must be superuser & the device must be 280 * configured in 281 */ 282 static int 283 tunopen(dev_t dev, int flag, int mode, struct lwp *l) 284 { 285 struct ifnet *ifp; 286 struct tun_softc *tp; 287 int error; 288 289 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE_TUN, 290 KAUTH_REQ_NETWORK_INTERFACE_TUN_ADD, NULL, NULL, NULL); 291 if (error) 292 return (error); 293 294 tp = tun_find_unit(dev); 295 296 if (tp == NULL) { 297 (void)tun_clone_create(&tun_cloner, minor(dev)); 298 tp = tun_find_unit(dev); 299 if (tp == NULL) { 300 error = ENXIO; 301 goto out_nolock; 302 } 303 } 304 305 if (tp->tun_flags & TUN_OPEN) { 306 error = EBUSY; 307 goto out; 308 } 309 310 ifp = &tp->tun_if; 311 tp->tun_flags |= TUN_OPEN; 312 TUNDEBUG("%s: open\n", ifp->if_xname); 313 out: 314 mutex_exit(&tp->tun_lock); 315 out_nolock: 316 return (error); 317 } 318 319 /* 320 * tunclose - close the device - mark i/f down & delete 321 * routing info 322 */ 323 int 324 tunclose(dev_t dev, int flag, int mode, 325 struct lwp *l) 326 { 327 struct tun_softc *tp; 328 struct ifnet *ifp; 329 330 if ((tp = tun_find_zunit(minor(dev))) != NULL) { 331 /* interface was "destroyed" before the close */ 332 seldestroy(&tp->tun_rsel); 333 seldestroy(&tp->tun_wsel); 334 softint_disestablish(tp->tun_osih); 335 softint_disestablish(tp->tun_isih); 336 mutex_destroy(&tp->tun_lock); 337 free(tp, M_DEVBUF); 338 goto out_nolock; 339 } 340 341 if ((tp = tun_find_unit(dev)) == NULL) 342 goto out_nolock; 343 344 ifp = &tp->tun_if; 345 346 tp->tun_flags &= ~TUN_OPEN; 347 348 tp->tun_pgid = 0; 349 selnotify(&tp->tun_rsel, 0, 0); 350 351 TUNDEBUG ("%s: closed\n", ifp->if_xname); 352 mutex_exit(&tp->tun_lock); 353 354 /* 355 * junk all pending output 356 */ 357 IFQ_PURGE(&ifp->if_snd); 358 359 if (ifp->if_flags & IFF_UP) { 360 if_down(ifp); 361 if (ifp->if_flags & IFF_RUNNING) { 362 /* find internet addresses and delete routes */ 363 struct ifaddr *ifa; 364 IFADDR_READER_FOREACH(ifa, ifp) { 365 #if defined(INET) || defined(INET6) 366 if (ifa->ifa_addr->sa_family == AF_INET || 367 ifa->ifa_addr->sa_family == AF_INET6) { 368 rtinit(ifa, (int)RTM_DELETE, 369 tp->tun_flags & TUN_DSTADDR 370 ? RTF_HOST 371 : 0); 372 } 373 #endif 374 } 375 } 376 } 377 out_nolock: 378 return (0); 379 } 380 381 /* 382 * Call at splnet(). 383 */ 384 static void 385 tuninit(struct tun_softc *tp) 386 { 387 struct ifnet *ifp = &tp->tun_if; 388 struct ifaddr *ifa; 389 390 TUNDEBUG("%s: tuninit\n", ifp->if_xname); 391 392 mutex_enter(&tp->tun_lock); 393 ifp->if_flags |= IFF_UP | IFF_RUNNING; 394 395 tp->tun_flags &= ~(TUN_IASET|TUN_DSTADDR); 396 IFADDR_READER_FOREACH(ifa, ifp) { 397 #ifdef INET 398 if (ifa->ifa_addr->sa_family == AF_INET) { 399 struct sockaddr_in *sin; 400 401 sin = satosin(ifa->ifa_addr); 402 if (sin && sin->sin_addr.s_addr) 403 tp->tun_flags |= TUN_IASET; 404 405 if (ifp->if_flags & IFF_POINTOPOINT) { 406 sin = satosin(ifa->ifa_dstaddr); 407 if (sin && sin->sin_addr.s_addr) 408 tp->tun_flags |= TUN_DSTADDR; 409 } 410 } 411 #endif 412 #ifdef INET6 413 if (ifa->ifa_addr->sa_family == AF_INET6) { 414 struct sockaddr_in6 *sin; 415 416 sin = (struct sockaddr_in6 *)ifa->ifa_addr; 417 if (!IN6_IS_ADDR_UNSPECIFIED(&sin->sin6_addr)) 418 tp->tun_flags |= TUN_IASET; 419 420 if (ifp->if_flags & IFF_POINTOPOINT) { 421 sin = (struct sockaddr_in6 *)ifa->ifa_dstaddr; 422 if (sin && 423 !IN6_IS_ADDR_UNSPECIFIED(&sin->sin6_addr)) 424 tp->tun_flags |= TUN_DSTADDR; 425 } else 426 tp->tun_flags &= ~TUN_DSTADDR; 427 } 428 #endif /* INET6 */ 429 } 430 mutex_exit(&tp->tun_lock); 431 } 432 433 /* 434 * Process an ioctl request. 435 */ 436 static int 437 tun_ioctl(struct ifnet *ifp, u_long cmd, void *data) 438 { 439 int error = 0, s; 440 struct tun_softc *tp = (struct tun_softc *)(ifp->if_softc); 441 struct ifreq *ifr = (struct ifreq *)data; 442 struct ifaddr *ifa = (struct ifaddr *)data; 443 444 s = splnet(); 445 446 switch (cmd) { 447 case SIOCINITIFADDR: 448 tuninit(tp); 449 ifa->ifa_rtrequest = p2p_rtrequest; 450 TUNDEBUG("%s: address set\n", ifp->if_xname); 451 break; 452 case SIOCSIFBRDADDR: 453 TUNDEBUG("%s: broadcast address set\n", ifp->if_xname); 454 break; 455 case SIOCSIFMTU: 456 if (ifr->ifr_mtu > TUNMTU || ifr->ifr_mtu < 576) { 457 error = EINVAL; 458 break; 459 } 460 TUNDEBUG("%s: interface mtu set\n", ifp->if_xname); 461 if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET) 462 error = 0; 463 break; 464 case SIOCADDMULTI: 465 case SIOCDELMULTI: 466 if (ifr == NULL) { 467 error = EAFNOSUPPORT; /* XXX */ 468 break; 469 } 470 switch (ifreq_getaddr(cmd, ifr)->sa_family) { 471 #ifdef INET 472 case AF_INET: 473 break; 474 #endif 475 #ifdef INET6 476 case AF_INET6: 477 break; 478 #endif 479 default: 480 error = EAFNOSUPPORT; 481 break; 482 } 483 break; 484 default: 485 error = ifioctl_common(ifp, cmd, data); 486 } 487 488 splx(s); 489 return (error); 490 } 491 492 /* 493 * tun_output - queue packets from higher level ready to put out. 494 */ 495 static int 496 tun_output(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst, 497 const struct rtentry *rt) 498 { 499 struct tun_softc *tp = ifp->if_softc; 500 int s; 501 int error; 502 #if defined(INET) || defined(INET6) 503 int mlen; 504 uint32_t *af; 505 #endif 506 507 s = splnet(); 508 mutex_enter(&tp->tun_lock); 509 TUNDEBUG ("%s: tun_output\n", ifp->if_xname); 510 511 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 512 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, 513 tp->tun_flags); 514 error = EHOSTDOWN; 515 goto out; 516 } 517 518 /* 519 * if the queueing discipline needs packet classification, 520 * do it before prepending link headers. 521 */ 522 IFQ_CLASSIFY(&ifp->if_snd, m0, dst->sa_family); 523 524 bpf_mtap_af(ifp, dst->sa_family, m0); 525 526 switch(dst->sa_family) { 527 #ifdef INET6 528 case AF_INET6: 529 #endif 530 #ifdef INET 531 case AF_INET: 532 #endif 533 #if defined(INET) || defined(INET6) 534 if (tp->tun_flags & TUN_PREPADDR) { 535 /* Simple link-layer header */ 536 M_PREPEND(m0, dst->sa_len, M_DONTWAIT); 537 if (m0 == NULL) { 538 IF_DROP(&ifp->if_snd); 539 error = ENOBUFS; 540 goto out; 541 } 542 bcopy(dst, mtod(m0, char *), dst->sa_len); 543 } 544 545 if (tp->tun_flags & TUN_IFHEAD) { 546 /* Prepend the address family */ 547 M_PREPEND(m0, sizeof(*af), M_DONTWAIT); 548 if (m0 == NULL) { 549 IF_DROP(&ifp->if_snd); 550 error = ENOBUFS; 551 goto out; 552 } 553 af = mtod(m0,uint32_t *); 554 *af = htonl(dst->sa_family); 555 } else { 556 #ifdef INET 557 if (dst->sa_family != AF_INET) 558 #endif 559 { 560 error = EAFNOSUPPORT; 561 goto out; 562 } 563 } 564 /* FALLTHROUGH */ 565 case AF_UNSPEC: 566 IFQ_ENQUEUE(&ifp->if_snd, m0, error); 567 if (error) { 568 ifp->if_collisions++; 569 error = EAFNOSUPPORT; 570 m0 = NULL; 571 goto out; 572 } 573 mlen = m0->m_pkthdr.len; 574 ifp->if_opackets++; 575 ifp->if_obytes += mlen; 576 break; 577 #endif 578 default: 579 error = EAFNOSUPPORT; 580 goto out; 581 } 582 583 if (tp->tun_flags & TUN_RWAIT) { 584 tp->tun_flags &= ~TUN_RWAIT; 585 wakeup((void *)tp); 586 } 587 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 588 softint_schedule(tp->tun_isih); 589 590 selnotify(&tp->tun_rsel, 0, 0); 591 out: 592 mutex_exit(&tp->tun_lock); 593 splx(s); 594 595 if (error && m0) { 596 m_freem(m0); 597 } 598 return 0; 599 } 600 601 static void 602 tun_i_softintr(void *cookie) 603 { 604 struct tun_softc *tp = cookie; 605 606 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 607 fownsignal(tp->tun_pgid, SIGIO, POLL_IN, POLLIN|POLLRDNORM, 608 NULL); 609 } 610 611 static void 612 tun_o_softintr(void *cookie) 613 { 614 struct tun_softc *tp = cookie; 615 616 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 617 fownsignal(tp->tun_pgid, SIGIO, POLL_OUT, POLLOUT|POLLWRNORM, 618 NULL); 619 } 620 621 /* 622 * the cdevsw interface is now pretty minimal. 623 */ 624 int 625 tunioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) 626 { 627 struct tun_softc *tp; 628 int s, error = 0; 629 630 s = splnet(); 631 tp = tun_find_unit(dev); 632 633 /* interface was "destroyed" already */ 634 if (tp == NULL) { 635 error = ENXIO; 636 goto out_nolock; 637 } 638 639 switch (cmd) { 640 case TUNSDEBUG: 641 tundebug = *(int *)data; 642 break; 643 644 case TUNGDEBUG: 645 *(int *)data = tundebug; 646 break; 647 648 case TUNSIFMODE: 649 switch (*(int *)data & (IFF_POINTOPOINT|IFF_BROADCAST)) { 650 case IFF_POINTOPOINT: 651 case IFF_BROADCAST: 652 if (tp->tun_if.if_flags & IFF_UP) { 653 error = EBUSY; 654 goto out; 655 } 656 tp->tun_if.if_flags &= 657 ~(IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST); 658 tp->tun_if.if_flags |= *(int *)data; 659 break; 660 default: 661 error = EINVAL; 662 goto out; 663 } 664 break; 665 666 case TUNSLMODE: 667 if (*(int *)data) { 668 tp->tun_flags |= TUN_PREPADDR; 669 tp->tun_flags &= ~TUN_IFHEAD; 670 } else 671 tp->tun_flags &= ~TUN_PREPADDR; 672 break; 673 674 case TUNSIFHEAD: 675 if (*(int *)data) { 676 tp->tun_flags |= TUN_IFHEAD; 677 tp->tun_flags &= ~TUN_PREPADDR; 678 } else 679 tp->tun_flags &= ~TUN_IFHEAD; 680 break; 681 682 case TUNGIFHEAD: 683 *(int *)data = (tp->tun_flags & TUN_IFHEAD); 684 break; 685 686 case FIONBIO: 687 if (*(int *)data) 688 tp->tun_flags |= TUN_NBIO; 689 else 690 tp->tun_flags &= ~TUN_NBIO; 691 break; 692 693 case FIOASYNC: 694 if (*(int *)data) 695 tp->tun_flags |= TUN_ASYNC; 696 else 697 tp->tun_flags &= ~TUN_ASYNC; 698 break; 699 700 case FIONREAD: 701 if (tp->tun_if.if_snd.ifq_head) 702 *(int *)data = tp->tun_if.if_snd.ifq_head->m_pkthdr.len; 703 else 704 *(int *)data = 0; 705 break; 706 707 case TIOCSPGRP: 708 case FIOSETOWN: 709 error = fsetown(&tp->tun_pgid, cmd, data); 710 break; 711 712 case TIOCGPGRP: 713 case FIOGETOWN: 714 error = fgetown(tp->tun_pgid, cmd, data); 715 break; 716 717 default: 718 error = ENOTTY; 719 } 720 721 out: 722 mutex_exit(&tp->tun_lock); 723 out_nolock: 724 splx(s); 725 return (error); 726 } 727 728 /* 729 * The cdevsw read interface - reads a packet at a time, or at 730 * least as much of a packet as can be read. 731 */ 732 int 733 tunread(dev_t dev, struct uio *uio, int ioflag) 734 { 735 struct tun_softc *tp; 736 struct ifnet *ifp; 737 struct mbuf *m, *m0; 738 int error = 0, len, s, index; 739 740 s = splnet(); 741 tp = tun_find_unit(dev); 742 743 /* interface was "destroyed" already */ 744 if (tp == NULL) { 745 error = ENXIO; 746 goto out_nolock; 747 } 748 749 index = tp->tun_if.if_index; 750 ifp = &tp->tun_if; 751 752 TUNDEBUG ("%s: read\n", ifp->if_xname); 753 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 754 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, tp->tun_flags); 755 error = EHOSTDOWN; 756 goto out; 757 } 758 759 tp->tun_flags &= ~TUN_RWAIT; 760 761 do { 762 IFQ_DEQUEUE(&ifp->if_snd, m0); 763 if (m0 == 0) { 764 if (tp->tun_flags & TUN_NBIO) { 765 error = EWOULDBLOCK; 766 goto out; 767 } 768 tp->tun_flags |= TUN_RWAIT; 769 if (mtsleep((void *)tp, PZERO|PCATCH|PNORELOCK, 770 "tunread", 0, &tp->tun_lock) != 0) { 771 error = EINTR; 772 goto out_nolock; 773 } else { 774 /* 775 * Maybe the interface was destroyed while 776 * we were sleeping, so let's ensure that 777 * we're looking at the same (valid) tun 778 * interface before looping. 779 */ 780 tp = tun_find_unit(dev); 781 if (tp == NULL) { 782 error = ENXIO; 783 goto out_nolock; 784 } 785 if (tp->tun_if.if_index != index) { 786 error = ENXIO; 787 goto out; 788 } 789 } 790 } 791 } while (m0 == 0); 792 793 mutex_exit(&tp->tun_lock); 794 splx(s); 795 796 /* Copy the mbuf chain */ 797 while (m0 && uio->uio_resid > 0 && error == 0) { 798 len = min(uio->uio_resid, m0->m_len); 799 if (len != 0) 800 error = uiomove(mtod(m0, void *), len, uio); 801 MFREE(m0, m); 802 m0 = m; 803 } 804 805 if (m0) { 806 TUNDEBUG("Dropping mbuf\n"); 807 m_freem(m0); 808 } 809 if (error) 810 ifp->if_ierrors++; 811 812 return (error); 813 814 out: 815 mutex_exit(&tp->tun_lock); 816 out_nolock: 817 splx(s); 818 return (error); 819 } 820 821 /* 822 * the cdevsw write interface - an atomic write is a packet - or else! 823 */ 824 int 825 tunwrite(dev_t dev, struct uio *uio, int ioflag) 826 { 827 struct tun_softc *tp; 828 struct ifnet *ifp; 829 struct mbuf *top, **mp, *m; 830 pktqueue_t *pktq; 831 struct sockaddr dst; 832 int error = 0, s, tlen, mlen; 833 uint32_t family; 834 835 s = splnet(); 836 tp = tun_find_unit(dev); 837 838 /* interface was "destroyed" already */ 839 if (tp == NULL) { 840 error = ENXIO; 841 goto out_nolock; 842 } 843 844 /* Unlock until we've got the data */ 845 mutex_exit(&tp->tun_lock); 846 splx(s); 847 848 ifp = &tp->tun_if; 849 850 TUNDEBUG("%s: tunwrite\n", ifp->if_xname); 851 852 if (tp->tun_flags & TUN_PREPADDR) { 853 if (uio->uio_resid < sizeof(dst)) { 854 error = EIO; 855 goto out0; 856 } 857 error = uiomove((void *)&dst, sizeof(dst), uio); 858 if (dst.sa_len > sizeof(dst)) { 859 /* Duh.. */ 860 char discard; 861 int n = dst.sa_len - sizeof(dst); 862 while (n--) 863 if ((error = uiomove(&discard, 1, uio)) != 0) { 864 goto out0; 865 } 866 } 867 } else if (tp->tun_flags & TUN_IFHEAD) { 868 if (uio->uio_resid < sizeof(family)){ 869 error = EIO; 870 goto out0; 871 } 872 error = uiomove((void *)&family, sizeof(family), uio); 873 dst.sa_family = ntohl(family); 874 } else { 875 #ifdef INET 876 dst.sa_family = AF_INET; 877 #endif 878 } 879 880 if (uio->uio_resid > TUNMTU) { 881 TUNDEBUG("%s: len=%lu!\n", ifp->if_xname, 882 (unsigned long)uio->uio_resid); 883 error = EIO; 884 goto out0; 885 } 886 887 switch (dst.sa_family) { 888 #ifdef INET 889 case AF_INET: 890 pktq = ip_pktq; 891 break; 892 #endif 893 #ifdef INET6 894 case AF_INET6: 895 pktq = ip6_pktq; 896 break; 897 #endif 898 default: 899 error = EAFNOSUPPORT; 900 goto out0; 901 } 902 903 tlen = uio->uio_resid; 904 905 /* get a header mbuf */ 906 MGETHDR(m, M_DONTWAIT, MT_DATA); 907 if (m == NULL) { 908 error = ENOBUFS; 909 goto out0; 910 } 911 mlen = MHLEN; 912 913 top = NULL; 914 mp = ⊤ 915 while (error == 0 && uio->uio_resid > 0) { 916 m->m_len = min(mlen, uio->uio_resid); 917 error = uiomove(mtod(m, void *), m->m_len, uio); 918 *mp = m; 919 mp = &m->m_next; 920 if (error == 0 && uio->uio_resid > 0) { 921 MGET(m, M_DONTWAIT, MT_DATA); 922 if (m == NULL) { 923 error = ENOBUFS; 924 break; 925 } 926 mlen = MLEN; 927 } 928 } 929 if (error) { 930 if (top != NULL) 931 m_freem (top); 932 ifp->if_ierrors++; 933 goto out0; 934 } 935 936 top->m_pkthdr.len = tlen; 937 m_set_rcvif(top, ifp); 938 939 bpf_mtap_af(ifp, dst.sa_family, top); 940 941 s = splnet(); 942 mutex_enter(&tp->tun_lock); 943 if ((tp->tun_flags & TUN_INITED) == 0) { 944 /* Interface was destroyed */ 945 error = ENXIO; 946 goto out; 947 } 948 if (__predict_false(!pktq_enqueue(pktq, top, 0))) { 949 ifp->if_collisions++; 950 mutex_exit(&tp->tun_lock); 951 error = ENOBUFS; 952 m_freem(top); 953 goto out_nolock; 954 } 955 ifp->if_ipackets++; 956 ifp->if_ibytes += tlen; 957 out: 958 mutex_exit(&tp->tun_lock); 959 out_nolock: 960 splx(s); 961 out0: 962 return (error); 963 } 964 965 #ifdef ALTQ 966 /* 967 * Start packet transmission on the interface. 968 * when the interface queue is rate-limited by ALTQ or TBR, 969 * if_start is needed to drain packets from the queue in order 970 * to notify readers when outgoing packets become ready. 971 * 972 * Should be called at splnet. 973 */ 974 static void 975 tunstart(struct ifnet *ifp) 976 { 977 struct tun_softc *tp = ifp->if_softc; 978 979 if (!ALTQ_IS_ENABLED(&ifp->if_snd) && !TBR_IS_ENABLED(&ifp->if_snd)) 980 return; 981 982 mutex_enter(&tp->tun_lock); 983 if (!IF_IS_EMPTY(&ifp->if_snd)) { 984 if (tp->tun_flags & TUN_RWAIT) { 985 tp->tun_flags &= ~TUN_RWAIT; 986 wakeup((void *)tp); 987 } 988 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 989 softint_schedule(tp->tun_osih); 990 991 selnotify(&tp->tun_rsel, 0, 0); 992 } 993 mutex_exit(&tp->tun_lock); 994 } 995 #endif /* ALTQ */ 996 /* 997 * tunpoll - the poll interface, this is only useful on reads 998 * really. The write detect always returns true, write never blocks 999 * anyway, it either accepts the packet or drops it. 1000 */ 1001 int 1002 tunpoll(dev_t dev, int events, struct lwp *l) 1003 { 1004 struct tun_softc *tp; 1005 struct ifnet *ifp; 1006 int s, revents = 0; 1007 1008 s = splnet(); 1009 tp = tun_find_unit(dev); 1010 1011 /* interface was "destroyed" already */ 1012 if (tp == NULL) 1013 goto out_nolock; 1014 1015 ifp = &tp->tun_if; 1016 1017 TUNDEBUG("%s: tunpoll\n", ifp->if_xname); 1018 1019 if (events & (POLLIN | POLLRDNORM)) { 1020 if (!IFQ_IS_EMPTY(&ifp->if_snd)) { 1021 TUNDEBUG("%s: tunpoll q=%d\n", ifp->if_xname, 1022 ifp->if_snd.ifq_len); 1023 revents |= events & (POLLIN | POLLRDNORM); 1024 } else { 1025 TUNDEBUG("%s: tunpoll waiting\n", ifp->if_xname); 1026 selrecord(l, &tp->tun_rsel); 1027 } 1028 } 1029 1030 if (events & (POLLOUT | POLLWRNORM)) 1031 revents |= events & (POLLOUT | POLLWRNORM); 1032 1033 mutex_exit(&tp->tun_lock); 1034 out_nolock: 1035 splx(s); 1036 return (revents); 1037 } 1038 1039 static void 1040 filt_tunrdetach(struct knote *kn) 1041 { 1042 struct tun_softc *tp = kn->kn_hook; 1043 int s; 1044 1045 s = splnet(); 1046 SLIST_REMOVE(&tp->tun_rsel.sel_klist, kn, knote, kn_selnext); 1047 splx(s); 1048 } 1049 1050 static int 1051 filt_tunread(struct knote *kn, long hint) 1052 { 1053 struct tun_softc *tp = kn->kn_hook; 1054 struct ifnet *ifp = &tp->tun_if; 1055 struct mbuf *m; 1056 int s; 1057 1058 s = splnet(); 1059 IF_POLL(&ifp->if_snd, m); 1060 if (m == NULL) { 1061 splx(s); 1062 return (0); 1063 } 1064 1065 for (kn->kn_data = 0; m != NULL; m = m->m_next) 1066 kn->kn_data += m->m_len; 1067 1068 splx(s); 1069 return (1); 1070 } 1071 1072 static const struct filterops tunread_filtops = 1073 { 1, NULL, filt_tunrdetach, filt_tunread }; 1074 1075 static const struct filterops tun_seltrue_filtops = 1076 { 1, NULL, filt_tunrdetach, filt_seltrue }; 1077 1078 int 1079 tunkqfilter(dev_t dev, struct knote *kn) 1080 { 1081 struct tun_softc *tp; 1082 struct klist *klist; 1083 int rv = 0, s; 1084 1085 s = splnet(); 1086 tp = tun_find_unit(dev); 1087 if (tp == NULL) 1088 goto out_nolock; 1089 1090 switch (kn->kn_filter) { 1091 case EVFILT_READ: 1092 klist = &tp->tun_rsel.sel_klist; 1093 kn->kn_fop = &tunread_filtops; 1094 break; 1095 1096 case EVFILT_WRITE: 1097 klist = &tp->tun_rsel.sel_klist; 1098 kn->kn_fop = &tun_seltrue_filtops; 1099 break; 1100 1101 default: 1102 rv = EINVAL; 1103 goto out; 1104 } 1105 1106 kn->kn_hook = tp; 1107 1108 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 1109 1110 out: 1111 mutex_exit(&tp->tun_lock); 1112 out_nolock: 1113 splx(s); 1114 return (rv); 1115 } 1116