if_tun.c revision 1.120.4.6
1 /* $NetBSD: if_tun.c,v 1.120.4.6 2016/10/05 20:56:08 skrll Exp $ */ 2 3 /* 4 * Copyright (c) 1988, Julian Onions <jpo (at) 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 1.120.4.6 2016/10/05 20:56:08 skrll 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 #include <sys/device.h> 43 #include <sys/module.h> 44 45 #include <net/if.h> 46 #include <net/if_types.h> 47 #include <net/netisr.h> 48 #include <net/route.h> 49 50 51 #ifdef INET 52 #include <netinet/in.h> 53 #include <netinet/in_systm.h> 54 #include <netinet/in_var.h> 55 #include <netinet/ip.h> 56 #include <netinet/if_inarp.h> 57 #endif 58 59 60 #include <sys/time.h> 61 #include <net/bpf.h> 62 63 #include <net/if_tun.h> 64 65 #include "ioconf.h" 66 67 #define TUNDEBUG if (tundebug) printf 68 int tundebug = 0; 69 70 extern int ifqmaxlen; 71 72 static LIST_HEAD(, tun_softc) tun_softc_list; 73 static LIST_HEAD(, tun_softc) tunz_softc_list; 74 static kmutex_t tun_softc_lock; 75 76 static int tun_ioctl(struct ifnet *, u_long, void *); 77 static int tun_output(struct ifnet *, struct mbuf *, 78 const struct sockaddr *, const struct rtentry *rt); 79 static int tun_clone_create(struct if_clone *, int); 80 static int tun_clone_destroy(struct ifnet *); 81 82 static struct if_clone tun_cloner = 83 IF_CLONE_INITIALIZER("tun", tun_clone_create, tun_clone_destroy); 84 85 static void tunattach0(struct tun_softc *); 86 static void tun_enable(struct tun_softc *, const struct ifaddr *); 87 static void tun_i_softintr(void *); 88 static void tun_o_softintr(void *); 89 #ifdef ALTQ 90 static void tunstart(struct ifnet *); 91 #endif 92 static struct tun_softc *tun_find_unit(dev_t); 93 static struct tun_softc *tun_find_zunit(int); 94 95 static dev_type_open(tunopen); 96 static dev_type_close(tunclose); 97 static dev_type_read(tunread); 98 static dev_type_write(tunwrite); 99 static dev_type_ioctl(tunioctl); 100 static dev_type_poll(tunpoll); 101 static dev_type_kqfilter(tunkqfilter); 102 103 const struct cdevsw tun_cdevsw = { 104 .d_open = tunopen, 105 .d_close = tunclose, 106 .d_read = tunread, 107 .d_write = tunwrite, 108 .d_ioctl = tunioctl, 109 .d_stop = nostop, 110 .d_tty = notty, 111 .d_poll = tunpoll, 112 .d_mmap = nommap, 113 .d_kqfilter = tunkqfilter, 114 .d_discard = nodiscard, 115 .d_flag = D_OTHER 116 }; 117 118 #ifdef _MODULE 119 devmajor_t tun_bmajor = -1, tun_cmajor = -1; 120 #endif 121 122 void 123 tunattach(int unused) 124 { 125 126 /* 127 * Nothing to do here, initialization is handled by the 128 * module initialization code in tuninit() below). 129 */ 130 } 131 132 static void 133 tuninit(void) 134 { 135 136 mutex_init(&tun_softc_lock, MUTEX_DEFAULT, IPL_NET); 137 LIST_INIT(&tun_softc_list); 138 LIST_INIT(&tunz_softc_list); 139 if_clone_attach(&tun_cloner); 140 #ifdef _MODULE 141 devsw_attach("tun", NULL, &tun_bmajor, &tun_cdevsw, &tun_cmajor); 142 #endif 143 } 144 145 static int 146 tundetach(void) 147 { 148 int error = 0; 149 150 if (!LIST_EMPTY(&tun_softc_list) || !LIST_EMPTY(&tunz_softc_list)) 151 error = EBUSY; 152 153 #ifdef _MODULE 154 if (error == 0) 155 error = devsw_detach(NULL, &tun_cdevsw); 156 #endif 157 if (error == 0) { 158 if_clone_detach(&tun_cloner); 159 mutex_destroy(&tun_softc_lock); 160 } 161 162 return error; 163 } 164 165 /* 166 * Find driver instance from dev_t. 167 * Returns with tp locked (if found). 168 */ 169 static struct tun_softc * 170 tun_find_unit(dev_t dev) 171 { 172 struct tun_softc *tp; 173 int unit = minor(dev); 174 175 mutex_enter(&tun_softc_lock); 176 LIST_FOREACH(tp, &tun_softc_list, tun_list) 177 if (unit == tp->tun_unit) 178 break; 179 if (tp) 180 mutex_enter(&tp->tun_lock); 181 mutex_exit(&tun_softc_lock); 182 183 return (tp); 184 } 185 186 /* 187 * Find zombie driver instance by unit number. 188 * Remove tp from list and return it unlocked (if found). 189 */ 190 static struct tun_softc * 191 tun_find_zunit(int unit) 192 { 193 struct tun_softc *tp; 194 195 mutex_enter(&tun_softc_lock); 196 LIST_FOREACH(tp, &tunz_softc_list, tun_list) 197 if (unit == tp->tun_unit) 198 break; 199 if (tp) 200 LIST_REMOVE(tp, tun_list); 201 mutex_exit(&tun_softc_lock); 202 #ifdef DIAGNOSTIC 203 if (tp != NULL && (tp->tun_flags & (TUN_INITED|TUN_OPEN)) != TUN_OPEN) 204 printf("tun%d: inconsistent flags: %x\n", unit, tp->tun_flags); 205 #endif 206 207 return (tp); 208 } 209 210 static int 211 tun_clone_create(struct if_clone *ifc, int unit) 212 { 213 struct tun_softc *tp; 214 215 if ((tp = tun_find_zunit(unit)) == NULL) { 216 /* Allocate a new instance */ 217 tp = malloc(sizeof(*tp), M_DEVBUF, M_WAITOK|M_ZERO); 218 219 tp->tun_unit = unit; 220 mutex_init(&tp->tun_lock, MUTEX_DEFAULT, IPL_NET); 221 selinit(&tp->tun_rsel); 222 selinit(&tp->tun_wsel); 223 } else { 224 /* Revive tunnel instance; clear ifp part */ 225 (void)memset(&tp->tun_if, 0, sizeof(struct ifnet)); 226 } 227 228 if_initname(&tp->tun_if, ifc->ifc_name, unit); 229 tunattach0(tp); 230 tp->tun_flags |= TUN_INITED; 231 tp->tun_osih = softint_establish(SOFTINT_CLOCK, tun_o_softintr, tp); 232 tp->tun_isih = softint_establish(SOFTINT_CLOCK, tun_i_softintr, tp); 233 234 mutex_enter(&tun_softc_lock); 235 LIST_INSERT_HEAD(&tun_softc_list, tp, tun_list); 236 mutex_exit(&tun_softc_lock); 237 238 return (0); 239 } 240 241 static void 242 tunattach0(struct tun_softc *tp) 243 { 244 struct ifnet *ifp; 245 246 ifp = &tp->tun_if; 247 ifp->if_softc = tp; 248 ifp->if_mtu = TUNMTU; 249 ifp->if_ioctl = tun_ioctl; 250 ifp->if_output = tun_output; 251 #ifdef ALTQ 252 ifp->if_start = tunstart; 253 #endif 254 ifp->if_flags = IFF_POINTOPOINT; 255 ifp->if_type = IFT_TUNNEL; 256 ifp->if_snd.ifq_maxlen = ifqmaxlen; 257 ifp->if_collisions = 0; 258 ifp->if_ierrors = 0; 259 ifp->if_oerrors = 0; 260 ifp->if_ipackets = 0; 261 ifp->if_opackets = 0; 262 ifp->if_ibytes = 0; 263 ifp->if_obytes = 0; 264 ifp->if_dlt = DLT_NULL; 265 IFQ_SET_READY(&ifp->if_snd); 266 if_attach(ifp); 267 if_alloc_sadl(ifp); 268 bpf_attach(ifp, DLT_NULL, sizeof(uint32_t)); 269 } 270 271 static int 272 tun_clone_destroy(struct ifnet *ifp) 273 { 274 struct tun_softc *tp = (void *)ifp; 275 int zombie = 0; 276 277 IF_PURGE(&ifp->if_snd); 278 ifp->if_flags &= ~IFF_RUNNING; 279 280 mutex_enter(&tun_softc_lock); 281 mutex_enter(&tp->tun_lock); 282 LIST_REMOVE(tp, tun_list); 283 if (tp->tun_flags & TUN_OPEN) { 284 /* Hang on to storage until last close */ 285 zombie = 1; 286 tp->tun_flags &= ~TUN_INITED; 287 LIST_INSERT_HEAD(&tunz_softc_list, tp, tun_list); 288 } 289 mutex_exit(&tun_softc_lock); 290 291 if (tp->tun_flags & TUN_RWAIT) { 292 tp->tun_flags &= ~TUN_RWAIT; 293 wakeup((void *)tp); 294 } 295 selnotify(&tp->tun_rsel, 0, 0); 296 297 mutex_exit(&tp->tun_lock); 298 299 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 300 fownsignal(tp->tun_pgid, SIGIO, POLL_HUP, 0, NULL); 301 302 bpf_detach(ifp); 303 if_detach(ifp); 304 305 if (!zombie) { 306 seldestroy(&tp->tun_rsel); 307 seldestroy(&tp->tun_wsel); 308 softint_disestablish(tp->tun_osih); 309 softint_disestablish(tp->tun_isih); 310 mutex_destroy(&tp->tun_lock); 311 free(tp, M_DEVBUF); 312 } 313 314 return (0); 315 } 316 317 /* 318 * tunnel open - must be superuser & the device must be 319 * configured in 320 */ 321 static int 322 tunopen(dev_t dev, int flag, int mode, struct lwp *l) 323 { 324 struct ifnet *ifp; 325 struct tun_softc *tp; 326 int error; 327 328 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE_TUN, 329 KAUTH_REQ_NETWORK_INTERFACE_TUN_ADD, NULL, NULL, NULL); 330 if (error) 331 return (error); 332 333 tp = tun_find_unit(dev); 334 335 if (tp == NULL) { 336 (void)tun_clone_create(&tun_cloner, minor(dev)); 337 tp = tun_find_unit(dev); 338 if (tp == NULL) { 339 error = ENXIO; 340 goto out_nolock; 341 } 342 } 343 344 if (tp->tun_flags & TUN_OPEN) { 345 error = EBUSY; 346 goto out; 347 } 348 349 ifp = &tp->tun_if; 350 tp->tun_flags |= TUN_OPEN; 351 TUNDEBUG("%s: open\n", ifp->if_xname); 352 out: 353 mutex_exit(&tp->tun_lock); 354 out_nolock: 355 return (error); 356 } 357 358 /* 359 * tunclose - close the device - mark i/f down & delete 360 * routing info 361 */ 362 int 363 tunclose(dev_t dev, int flag, int mode, 364 struct lwp *l) 365 { 366 struct tun_softc *tp; 367 struct ifnet *ifp; 368 369 if ((tp = tun_find_zunit(minor(dev))) != NULL) { 370 /* interface was "destroyed" before the close */ 371 seldestroy(&tp->tun_rsel); 372 seldestroy(&tp->tun_wsel); 373 softint_disestablish(tp->tun_osih); 374 softint_disestablish(tp->tun_isih); 375 mutex_destroy(&tp->tun_lock); 376 free(tp, M_DEVBUF); 377 goto out_nolock; 378 } 379 380 if ((tp = tun_find_unit(dev)) == NULL) 381 goto out_nolock; 382 383 ifp = &tp->tun_if; 384 385 tp->tun_flags &= ~TUN_OPEN; 386 387 tp->tun_pgid = 0; 388 selnotify(&tp->tun_rsel, 0, 0); 389 390 TUNDEBUG ("%s: closed\n", ifp->if_xname); 391 mutex_exit(&tp->tun_lock); 392 393 /* 394 * junk all pending output 395 */ 396 IFQ_PURGE(&ifp->if_snd); 397 398 if (ifp->if_flags & IFF_UP) { 399 if_down(ifp); 400 if (ifp->if_flags & IFF_RUNNING) { 401 /* find internet addresses and delete routes */ 402 struct ifaddr *ifa; 403 IFADDR_READER_FOREACH(ifa, ifp) { 404 #if defined(INET) || defined(INET6) 405 if (ifa->ifa_addr->sa_family == AF_INET || 406 ifa->ifa_addr->sa_family == AF_INET6) { 407 rtinit(ifa, (int)RTM_DELETE, 408 tp->tun_flags & TUN_DSTADDR 409 ? RTF_HOST 410 : 0); 411 } 412 #endif 413 } 414 } 415 } 416 out_nolock: 417 return (0); 418 } 419 420 /* 421 * Call at splnet(). 422 */ 423 static void 424 tun_enable(struct tun_softc *tp, const struct ifaddr *ifa) 425 { 426 struct ifnet *ifp = &tp->tun_if; 427 428 TUNDEBUG("%s: %s\n", __func__, ifp->if_xname); 429 430 mutex_enter(&tp->tun_lock); 431 ifp->if_flags |= IFF_UP | IFF_RUNNING; 432 433 tp->tun_flags &= ~(TUN_IASET|TUN_DSTADDR); 434 435 switch (ifa->ifa_addr->sa_family) { 436 #ifdef INET 437 case AF_INET: { 438 struct sockaddr_in *sin; 439 440 sin = satosin(ifa->ifa_addr); 441 if (sin && sin->sin_addr.s_addr) 442 tp->tun_flags |= TUN_IASET; 443 444 if (ifp->if_flags & IFF_POINTOPOINT) { 445 sin = satosin(ifa->ifa_dstaddr); 446 if (sin && sin->sin_addr.s_addr) 447 tp->tun_flags |= TUN_DSTADDR; 448 } 449 break; 450 } 451 #endif 452 #ifdef INET6 453 case AF_INET6: { 454 struct sockaddr_in6 *sin; 455 456 sin = satosin6(ifa->ifa_addr); 457 if (!IN6_IS_ADDR_UNSPECIFIED(&sin->sin6_addr)) 458 tp->tun_flags |= TUN_IASET; 459 460 if (ifp->if_flags & IFF_POINTOPOINT) { 461 sin = satosin6(ifa->ifa_dstaddr); 462 if (sin && !IN6_IS_ADDR_UNSPECIFIED(&sin->sin6_addr)) 463 tp->tun_flags |= TUN_DSTADDR; 464 } else 465 tp->tun_flags &= ~TUN_DSTADDR; 466 break; 467 } 468 #endif /* INET6 */ 469 default: 470 break; 471 } 472 mutex_exit(&tp->tun_lock); 473 } 474 475 /* 476 * Process an ioctl request. 477 */ 478 static int 479 tun_ioctl(struct ifnet *ifp, u_long cmd, void *data) 480 { 481 int error = 0, s; 482 struct tun_softc *tp = (struct tun_softc *)(ifp->if_softc); 483 struct ifreq *ifr = (struct ifreq *)data; 484 struct ifaddr *ifa = (struct ifaddr *)data; 485 486 s = splnet(); 487 488 switch (cmd) { 489 case SIOCINITIFADDR: 490 tun_enable(tp, ifa); 491 ifa->ifa_rtrequest = p2p_rtrequest; 492 TUNDEBUG("%s: address set\n", ifp->if_xname); 493 break; 494 case SIOCSIFBRDADDR: 495 TUNDEBUG("%s: broadcast address set\n", ifp->if_xname); 496 break; 497 case SIOCSIFMTU: 498 if (ifr->ifr_mtu > TUNMTU || ifr->ifr_mtu < 576) { 499 error = EINVAL; 500 break; 501 } 502 TUNDEBUG("%s: interface mtu set\n", ifp->if_xname); 503 if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET) 504 error = 0; 505 break; 506 case SIOCADDMULTI: 507 case SIOCDELMULTI: 508 if (ifr == NULL) { 509 error = EAFNOSUPPORT; /* XXX */ 510 break; 511 } 512 switch (ifreq_getaddr(cmd, ifr)->sa_family) { 513 #ifdef INET 514 case AF_INET: 515 break; 516 #endif 517 #ifdef INET6 518 case AF_INET6: 519 break; 520 #endif 521 default: 522 error = EAFNOSUPPORT; 523 break; 524 } 525 break; 526 default: 527 error = ifioctl_common(ifp, cmd, data); 528 } 529 530 splx(s); 531 return (error); 532 } 533 534 /* 535 * tun_output - queue packets from higher level ready to put out. 536 */ 537 static int 538 tun_output(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst, 539 const struct rtentry *rt) 540 { 541 struct tun_softc *tp = ifp->if_softc; 542 int s; 543 int error; 544 #if defined(INET) || defined(INET6) 545 int mlen; 546 uint32_t *af; 547 #endif 548 549 s = splnet(); 550 mutex_enter(&tp->tun_lock); 551 TUNDEBUG ("%s: tun_output\n", ifp->if_xname); 552 553 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 554 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, 555 tp->tun_flags); 556 error = EHOSTDOWN; 557 goto out; 558 } 559 560 /* 561 * if the queueing discipline needs packet classification, 562 * do it before prepending link headers. 563 */ 564 IFQ_CLASSIFY(&ifp->if_snd, m0, dst->sa_family); 565 566 bpf_mtap_af(ifp, dst->sa_family, m0); 567 568 switch(dst->sa_family) { 569 #ifdef INET6 570 case AF_INET6: 571 #endif 572 #ifdef INET 573 case AF_INET: 574 #endif 575 #if defined(INET) || defined(INET6) 576 if (tp->tun_flags & TUN_PREPADDR) { 577 /* Simple link-layer header */ 578 M_PREPEND(m0, dst->sa_len, M_DONTWAIT); 579 if (m0 == NULL) { 580 IF_DROP(&ifp->if_snd); 581 error = ENOBUFS; 582 goto out; 583 } 584 bcopy(dst, mtod(m0, char *), dst->sa_len); 585 } 586 587 if (tp->tun_flags & TUN_IFHEAD) { 588 /* Prepend the address family */ 589 M_PREPEND(m0, sizeof(*af), M_DONTWAIT); 590 if (m0 == NULL) { 591 IF_DROP(&ifp->if_snd); 592 error = ENOBUFS; 593 goto out; 594 } 595 af = mtod(m0,uint32_t *); 596 *af = htonl(dst->sa_family); 597 } else { 598 #ifdef INET 599 if (dst->sa_family != AF_INET) 600 #endif 601 { 602 error = EAFNOSUPPORT; 603 goto out; 604 } 605 } 606 /* FALLTHROUGH */ 607 case AF_UNSPEC: 608 IFQ_ENQUEUE(&ifp->if_snd, m0, error); 609 if (error) { 610 ifp->if_collisions++; 611 error = EAFNOSUPPORT; 612 m0 = NULL; 613 goto out; 614 } 615 mlen = m0->m_pkthdr.len; 616 ifp->if_opackets++; 617 ifp->if_obytes += mlen; 618 break; 619 #endif 620 default: 621 error = EAFNOSUPPORT; 622 goto out; 623 } 624 625 if (tp->tun_flags & TUN_RWAIT) { 626 tp->tun_flags &= ~TUN_RWAIT; 627 wakeup((void *)tp); 628 } 629 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 630 softint_schedule(tp->tun_isih); 631 632 selnotify(&tp->tun_rsel, 0, 0); 633 out: 634 mutex_exit(&tp->tun_lock); 635 splx(s); 636 637 if (error && m0) { 638 m_freem(m0); 639 } 640 return 0; 641 } 642 643 static void 644 tun_i_softintr(void *cookie) 645 { 646 struct tun_softc *tp = cookie; 647 648 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 649 fownsignal(tp->tun_pgid, SIGIO, POLL_IN, POLLIN|POLLRDNORM, 650 NULL); 651 } 652 653 static void 654 tun_o_softintr(void *cookie) 655 { 656 struct tun_softc *tp = cookie; 657 658 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 659 fownsignal(tp->tun_pgid, SIGIO, POLL_OUT, POLLOUT|POLLWRNORM, 660 NULL); 661 } 662 663 /* 664 * the cdevsw interface is now pretty minimal. 665 */ 666 int 667 tunioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) 668 { 669 struct tun_softc *tp; 670 int s, error = 0; 671 672 s = splnet(); 673 tp = tun_find_unit(dev); 674 675 /* interface was "destroyed" already */ 676 if (tp == NULL) { 677 error = ENXIO; 678 goto out_nolock; 679 } 680 681 switch (cmd) { 682 case TUNSDEBUG: 683 tundebug = *(int *)data; 684 break; 685 686 case TUNGDEBUG: 687 *(int *)data = tundebug; 688 break; 689 690 case TUNSIFMODE: 691 switch (*(int *)data & (IFF_POINTOPOINT|IFF_BROADCAST)) { 692 case IFF_POINTOPOINT: 693 case IFF_BROADCAST: 694 if (tp->tun_if.if_flags & IFF_UP) { 695 error = EBUSY; 696 goto out; 697 } 698 tp->tun_if.if_flags &= 699 ~(IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST); 700 tp->tun_if.if_flags |= *(int *)data; 701 break; 702 default: 703 error = EINVAL; 704 goto out; 705 } 706 break; 707 708 case TUNSLMODE: 709 if (*(int *)data) { 710 tp->tun_flags |= TUN_PREPADDR; 711 tp->tun_flags &= ~TUN_IFHEAD; 712 } else 713 tp->tun_flags &= ~TUN_PREPADDR; 714 break; 715 716 case TUNSIFHEAD: 717 if (*(int *)data) { 718 tp->tun_flags |= TUN_IFHEAD; 719 tp->tun_flags &= ~TUN_PREPADDR; 720 } else 721 tp->tun_flags &= ~TUN_IFHEAD; 722 break; 723 724 case TUNGIFHEAD: 725 *(int *)data = (tp->tun_flags & TUN_IFHEAD); 726 break; 727 728 case FIONBIO: 729 if (*(int *)data) 730 tp->tun_flags |= TUN_NBIO; 731 else 732 tp->tun_flags &= ~TUN_NBIO; 733 break; 734 735 case FIOASYNC: 736 if (*(int *)data) 737 tp->tun_flags |= TUN_ASYNC; 738 else 739 tp->tun_flags &= ~TUN_ASYNC; 740 break; 741 742 case FIONREAD: 743 if (tp->tun_if.if_snd.ifq_head) 744 *(int *)data = tp->tun_if.if_snd.ifq_head->m_pkthdr.len; 745 else 746 *(int *)data = 0; 747 break; 748 749 case TIOCSPGRP: 750 case FIOSETOWN: 751 error = fsetown(&tp->tun_pgid, cmd, data); 752 break; 753 754 case TIOCGPGRP: 755 case FIOGETOWN: 756 error = fgetown(tp->tun_pgid, cmd, data); 757 break; 758 759 default: 760 error = ENOTTY; 761 } 762 763 out: 764 mutex_exit(&tp->tun_lock); 765 out_nolock: 766 splx(s); 767 return (error); 768 } 769 770 /* 771 * The cdevsw read interface - reads a packet at a time, or at 772 * least as much of a packet as can be read. 773 */ 774 int 775 tunread(dev_t dev, struct uio *uio, int ioflag) 776 { 777 struct tun_softc *tp; 778 struct ifnet *ifp; 779 struct mbuf *m, *m0; 780 int error = 0, len, s, index; 781 782 s = splnet(); 783 tp = tun_find_unit(dev); 784 785 /* interface was "destroyed" already */ 786 if (tp == NULL) { 787 error = ENXIO; 788 goto out_nolock; 789 } 790 791 index = tp->tun_if.if_index; 792 ifp = &tp->tun_if; 793 794 TUNDEBUG ("%s: read\n", ifp->if_xname); 795 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 796 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, tp->tun_flags); 797 error = EHOSTDOWN; 798 goto out; 799 } 800 801 tp->tun_flags &= ~TUN_RWAIT; 802 803 do { 804 IFQ_DEQUEUE(&ifp->if_snd, m0); 805 if (m0 == 0) { 806 if (tp->tun_flags & TUN_NBIO) { 807 error = EWOULDBLOCK; 808 goto out; 809 } 810 tp->tun_flags |= TUN_RWAIT; 811 if (mtsleep((void *)tp, PZERO|PCATCH|PNORELOCK, 812 "tunread", 0, &tp->tun_lock) != 0) { 813 error = EINTR; 814 goto out_nolock; 815 } else { 816 /* 817 * Maybe the interface was destroyed while 818 * we were sleeping, so let's ensure that 819 * we're looking at the same (valid) tun 820 * interface before looping. 821 */ 822 tp = tun_find_unit(dev); 823 if (tp == NULL) { 824 error = ENXIO; 825 goto out_nolock; 826 } 827 if (tp->tun_if.if_index != index) { 828 error = ENXIO; 829 goto out; 830 } 831 } 832 } 833 } while (m0 == 0); 834 835 mutex_exit(&tp->tun_lock); 836 splx(s); 837 838 /* Copy the mbuf chain */ 839 while (m0 && uio->uio_resid > 0 && error == 0) { 840 len = min(uio->uio_resid, m0->m_len); 841 if (len != 0) 842 error = uiomove(mtod(m0, void *), len, uio); 843 m0 = m = m_free(m0); 844 } 845 846 if (m0) { 847 TUNDEBUG("Dropping mbuf\n"); 848 m_freem(m0); 849 } 850 if (error) 851 ifp->if_ierrors++; 852 853 return (error); 854 855 out: 856 mutex_exit(&tp->tun_lock); 857 out_nolock: 858 splx(s); 859 return (error); 860 } 861 862 /* 863 * the cdevsw write interface - an atomic write is a packet - or else! 864 */ 865 int 866 tunwrite(dev_t dev, struct uio *uio, int ioflag) 867 { 868 struct tun_softc *tp; 869 struct ifnet *ifp; 870 struct mbuf *top, **mp, *m; 871 pktqueue_t *pktq; 872 struct sockaddr dst; 873 int error = 0, s, tlen, mlen; 874 uint32_t family; 875 876 s = splnet(); 877 tp = tun_find_unit(dev); 878 879 /* interface was "destroyed" already */ 880 if (tp == NULL) { 881 error = ENXIO; 882 goto out_nolock; 883 } 884 885 /* Unlock until we've got the data */ 886 mutex_exit(&tp->tun_lock); 887 splx(s); 888 889 ifp = &tp->tun_if; 890 891 TUNDEBUG("%s: tunwrite\n", ifp->if_xname); 892 893 if (tp->tun_flags & TUN_PREPADDR) { 894 if (uio->uio_resid < sizeof(dst)) { 895 error = EIO; 896 goto out0; 897 } 898 error = uiomove((void *)&dst, sizeof(dst), uio); 899 if (dst.sa_len > sizeof(dst)) { 900 /* Duh.. */ 901 char discard; 902 int n = dst.sa_len - sizeof(dst); 903 while (n--) 904 if ((error = uiomove(&discard, 1, uio)) != 0) { 905 goto out0; 906 } 907 } 908 } else if (tp->tun_flags & TUN_IFHEAD) { 909 if (uio->uio_resid < sizeof(family)){ 910 error = EIO; 911 goto out0; 912 } 913 error = uiomove((void *)&family, sizeof(family), uio); 914 dst.sa_family = ntohl(family); 915 } else { 916 #ifdef INET 917 dst.sa_family = AF_INET; 918 #endif 919 } 920 921 if (uio->uio_resid > TUNMTU) { 922 TUNDEBUG("%s: len=%lu!\n", ifp->if_xname, 923 (unsigned long)uio->uio_resid); 924 error = EIO; 925 goto out0; 926 } 927 928 switch (dst.sa_family) { 929 #ifdef INET 930 case AF_INET: 931 pktq = ip_pktq; 932 break; 933 #endif 934 #ifdef INET6 935 case AF_INET6: 936 pktq = ip6_pktq; 937 break; 938 #endif 939 default: 940 error = EAFNOSUPPORT; 941 goto out0; 942 } 943 944 tlen = uio->uio_resid; 945 946 /* get a header mbuf */ 947 MGETHDR(m, M_DONTWAIT, MT_DATA); 948 if (m == NULL) { 949 error = ENOBUFS; 950 goto out0; 951 } 952 mlen = MHLEN; 953 954 top = NULL; 955 mp = ⊤ 956 while (error == 0 && uio->uio_resid > 0) { 957 m->m_len = min(mlen, uio->uio_resid); 958 error = uiomove(mtod(m, void *), m->m_len, uio); 959 *mp = m; 960 mp = &m->m_next; 961 if (error == 0 && uio->uio_resid > 0) { 962 MGET(m, M_DONTWAIT, MT_DATA); 963 if (m == NULL) { 964 error = ENOBUFS; 965 break; 966 } 967 mlen = MLEN; 968 } 969 } 970 if (error) { 971 if (top != NULL) 972 m_freem (top); 973 ifp->if_ierrors++; 974 goto out0; 975 } 976 977 top->m_pkthdr.len = tlen; 978 m_set_rcvif(top, ifp); 979 980 bpf_mtap_af(ifp, dst.sa_family, top); 981 982 s = splnet(); 983 mutex_enter(&tp->tun_lock); 984 if ((tp->tun_flags & TUN_INITED) == 0) { 985 /* Interface was destroyed */ 986 error = ENXIO; 987 goto out; 988 } 989 if (__predict_false(!pktq_enqueue(pktq, top, 0))) { 990 ifp->if_collisions++; 991 mutex_exit(&tp->tun_lock); 992 error = ENOBUFS; 993 m_freem(top); 994 goto out_nolock; 995 } 996 ifp->if_ipackets++; 997 ifp->if_ibytes += tlen; 998 out: 999 mutex_exit(&tp->tun_lock); 1000 out_nolock: 1001 splx(s); 1002 out0: 1003 return (error); 1004 } 1005 1006 #ifdef ALTQ 1007 /* 1008 * Start packet transmission on the interface. 1009 * when the interface queue is rate-limited by ALTQ or TBR, 1010 * if_start is needed to drain packets from the queue in order 1011 * to notify readers when outgoing packets become ready. 1012 * 1013 * Should be called at splnet. 1014 */ 1015 static void 1016 tunstart(struct ifnet *ifp) 1017 { 1018 struct tun_softc *tp = ifp->if_softc; 1019 1020 if (!ALTQ_IS_ENABLED(&ifp->if_snd) && !TBR_IS_ENABLED(&ifp->if_snd)) 1021 return; 1022 1023 mutex_enter(&tp->tun_lock); 1024 if (!IF_IS_EMPTY(&ifp->if_snd)) { 1025 if (tp->tun_flags & TUN_RWAIT) { 1026 tp->tun_flags &= ~TUN_RWAIT; 1027 wakeup((void *)tp); 1028 } 1029 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 1030 softint_schedule(tp->tun_osih); 1031 1032 selnotify(&tp->tun_rsel, 0, 0); 1033 } 1034 mutex_exit(&tp->tun_lock); 1035 } 1036 #endif /* ALTQ */ 1037 /* 1038 * tunpoll - the poll interface, this is only useful on reads 1039 * really. The write detect always returns true, write never blocks 1040 * anyway, it either accepts the packet or drops it. 1041 */ 1042 int 1043 tunpoll(dev_t dev, int events, struct lwp *l) 1044 { 1045 struct tun_softc *tp; 1046 struct ifnet *ifp; 1047 int s, revents = 0; 1048 1049 s = splnet(); 1050 tp = tun_find_unit(dev); 1051 1052 /* interface was "destroyed" already */ 1053 if (tp == NULL) 1054 goto out_nolock; 1055 1056 ifp = &tp->tun_if; 1057 1058 TUNDEBUG("%s: tunpoll\n", ifp->if_xname); 1059 1060 if (events & (POLLIN | POLLRDNORM)) { 1061 if (!IFQ_IS_EMPTY(&ifp->if_snd)) { 1062 TUNDEBUG("%s: tunpoll q=%d\n", ifp->if_xname, 1063 ifp->if_snd.ifq_len); 1064 revents |= events & (POLLIN | POLLRDNORM); 1065 } else { 1066 TUNDEBUG("%s: tunpoll waiting\n", ifp->if_xname); 1067 selrecord(l, &tp->tun_rsel); 1068 } 1069 } 1070 1071 if (events & (POLLOUT | POLLWRNORM)) 1072 revents |= events & (POLLOUT | POLLWRNORM); 1073 1074 mutex_exit(&tp->tun_lock); 1075 out_nolock: 1076 splx(s); 1077 return (revents); 1078 } 1079 1080 static void 1081 filt_tunrdetach(struct knote *kn) 1082 { 1083 struct tun_softc *tp = kn->kn_hook; 1084 int s; 1085 1086 s = splnet(); 1087 SLIST_REMOVE(&tp->tun_rsel.sel_klist, kn, knote, kn_selnext); 1088 splx(s); 1089 } 1090 1091 static int 1092 filt_tunread(struct knote *kn, long hint) 1093 { 1094 struct tun_softc *tp = kn->kn_hook; 1095 struct ifnet *ifp = &tp->tun_if; 1096 struct mbuf *m; 1097 int s; 1098 1099 s = splnet(); 1100 IF_POLL(&ifp->if_snd, m); 1101 if (m == NULL) { 1102 splx(s); 1103 return (0); 1104 } 1105 1106 for (kn->kn_data = 0; m != NULL; m = m->m_next) 1107 kn->kn_data += m->m_len; 1108 1109 splx(s); 1110 return (1); 1111 } 1112 1113 static const struct filterops tunread_filtops = 1114 { 1, NULL, filt_tunrdetach, filt_tunread }; 1115 1116 static const struct filterops tun_seltrue_filtops = 1117 { 1, NULL, filt_tunrdetach, filt_seltrue }; 1118 1119 int 1120 tunkqfilter(dev_t dev, struct knote *kn) 1121 { 1122 struct tun_softc *tp; 1123 struct klist *klist; 1124 int rv = 0, s; 1125 1126 s = splnet(); 1127 tp = tun_find_unit(dev); 1128 if (tp == NULL) 1129 goto out_nolock; 1130 1131 switch (kn->kn_filter) { 1132 case EVFILT_READ: 1133 klist = &tp->tun_rsel.sel_klist; 1134 kn->kn_fop = &tunread_filtops; 1135 break; 1136 1137 case EVFILT_WRITE: 1138 klist = &tp->tun_rsel.sel_klist; 1139 kn->kn_fop = &tun_seltrue_filtops; 1140 break; 1141 1142 default: 1143 rv = EINVAL; 1144 goto out; 1145 } 1146 1147 kn->kn_hook = tp; 1148 1149 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 1150 1151 out: 1152 mutex_exit(&tp->tun_lock); 1153 out_nolock: 1154 splx(s); 1155 return (rv); 1156 } 1157 1158 /* 1159 * Module infrastructure 1160 */ 1161 #include "if_module.h" 1162 1163 IF_MODULE(MODULE_CLASS_DRIVER, tun, "") 1164
Indexes created Wed Oct 15 07:09:58 GMT 2025