if_tun.c revision 1.114.6.1
1 /* $NetBSD: if_tun.c,v 1.114.6.1 2012/02/18 07:35:38 mrg 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 1.114.6.1 2012/02/18 07:35:38 mrg Exp $"); 19 20 #include "opt_inet.h" 21 22 #include <sys/param.h> 23 #include <sys/proc.h> 24 #include <sys/systm.h> 25 #include <sys/mbuf.h> 26 #include <sys/buf.h> 27 #include <sys/protosw.h> 28 #include <sys/socket.h> 29 #include <sys/ioctl.h> 30 #include <sys/errno.h> 31 #include <sys/syslog.h> 32 #include <sys/select.h> 33 #include <sys/poll.h> 34 #include <sys/file.h> 35 #include <sys/signalvar.h> 36 #include <sys/conf.h> 37 #include <sys/kauth.h> 38 #include <sys/simplelock.h> 39 #include <sys/mutex.h> 40 #include <sys/cpu.h> 41 42 #include <net/if.h> 43 #include <net/if_types.h> 44 #include <net/netisr.h> 45 #include <net/route.h> 46 47 48 #ifdef INET 49 #include <netinet/in.h> 50 #include <netinet/in_systm.h> 51 #include <netinet/in_var.h> 52 #include <netinet/ip.h> 53 #include <netinet/if_inarp.h> 54 #endif 55 56 57 #include <sys/time.h> 58 #include <net/bpf.h> 59 60 #include <net/if_tun.h> 61 62 #define TUNDEBUG if (tundebug) printf 63 int tundebug = 0; 64 65 extern int ifqmaxlen; 66 void tunattach(int); 67 68 static LIST_HEAD(, tun_softc) tun_softc_list; 69 static LIST_HEAD(, tun_softc) tunz_softc_list; 70 static struct simplelock tun_softc_lock; 71 72 static int tun_ioctl(struct ifnet *, u_long, void *); 73 static int tun_output(struct ifnet *, struct mbuf *, 74 const struct sockaddr *, struct rtentry *rt); 75 static int tun_clone_create(struct if_clone *, int); 76 static int tun_clone_destroy(struct ifnet *); 77 78 static struct if_clone tun_cloner = 79 IF_CLONE_INITIALIZER("tun", tun_clone_create, tun_clone_destroy); 80 81 static void tunattach0(struct tun_softc *); 82 static void tuninit(struct tun_softc *); 83 static void tun_i_softintr(void *); 84 static void tun_o_softintr(void *); 85 #ifdef ALTQ 86 static void tunstart(struct ifnet *); 87 #endif 88 static struct tun_softc *tun_find_unit(dev_t); 89 static struct tun_softc *tun_find_zunit(int); 90 91 static dev_type_open(tunopen); 92 static dev_type_close(tunclose); 93 static dev_type_read(tunread); 94 static dev_type_write(tunwrite); 95 static dev_type_ioctl(tunioctl); 96 static dev_type_poll(tunpoll); 97 static dev_type_kqfilter(tunkqfilter); 98 99 const struct cdevsw tun_cdevsw = { 100 tunopen, tunclose, tunread, tunwrite, tunioctl, 101 nostop, notty, tunpoll, nommap, tunkqfilter, D_OTHER, 102 }; 103 104 void 105 tunattach(int unused) 106 { 107 108 simple_lock_init(&tun_softc_lock); 109 LIST_INIT(&tun_softc_list); 110 LIST_INIT(&tunz_softc_list); 111 if_clone_attach(&tun_cloner); 112 } 113 114 /* 115 * Find driver instance from dev_t. 116 * Call at splnet(). 117 * Returns with tp locked (if found). 118 */ 119 static struct tun_softc * 120 tun_find_unit(dev_t dev) 121 { 122 struct tun_softc *tp; 123 int unit = minor(dev); 124 125 simple_lock(&tun_softc_lock); 126 LIST_FOREACH(tp, &tun_softc_list, tun_list) 127 if (unit == tp->tun_unit) 128 break; 129 if (tp) 130 mutex_enter(&tp->tun_lock); 131 simple_unlock(&tun_softc_lock); 132 133 return (tp); 134 } 135 136 /* 137 * Find zombie driver instance by unit number. 138 * Call at splnet(). 139 * Remove tp from list and return it unlocked (if found). 140 */ 141 static struct tun_softc * 142 tun_find_zunit(int unit) 143 { 144 struct tun_softc *tp; 145 146 simple_lock(&tun_softc_lock); 147 LIST_FOREACH(tp, &tunz_softc_list, tun_list) 148 if (unit == tp->tun_unit) 149 break; 150 if (tp) 151 LIST_REMOVE(tp, tun_list); 152 simple_unlock(&tun_softc_lock); 153 #ifdef DIAGNOSTIC 154 if (tp != NULL && (tp->tun_flags & (TUN_INITED|TUN_OPEN)) != TUN_OPEN) 155 printf("tun%d: inconsistent flags: %x\n", unit, tp->tun_flags); 156 #endif 157 158 return (tp); 159 } 160 161 static int 162 tun_clone_create(struct if_clone *ifc, int unit) 163 { 164 struct tun_softc *tp; 165 166 if ((tp = tun_find_zunit(unit)) == NULL) { 167 /* Allocate a new instance */ 168 tp = malloc(sizeof(*tp), M_DEVBUF, M_WAITOK|M_ZERO); 169 170 tp->tun_unit = unit; 171 mutex_init(&tp->tun_lock, MUTEX_DEFAULT, IPL_NET); 172 selinit(&tp->tun_rsel); 173 selinit(&tp->tun_wsel); 174 } else { 175 /* Revive tunnel instance; clear ifp part */ 176 (void)memset(&tp->tun_if, 0, sizeof(struct ifnet)); 177 } 178 179 if_initname(&tp->tun_if, ifc->ifc_name, unit); 180 tunattach0(tp); 181 tp->tun_flags |= TUN_INITED; 182 tp->tun_osih = softint_establish(SOFTINT_CLOCK, tun_o_softintr, tp); 183 tp->tun_isih = softint_establish(SOFTINT_CLOCK, tun_i_softintr, tp); 184 185 simple_lock(&tun_softc_lock); 186 LIST_INSERT_HEAD(&tun_softc_list, tp, tun_list); 187 simple_unlock(&tun_softc_lock); 188 189 return (0); 190 } 191 192 static void 193 tunattach0(struct tun_softc *tp) 194 { 195 struct ifnet *ifp; 196 197 ifp = &tp->tun_if; 198 ifp->if_softc = tp; 199 ifp->if_mtu = TUNMTU; 200 ifp->if_ioctl = tun_ioctl; 201 ifp->if_output = tun_output; 202 #ifdef ALTQ 203 ifp->if_start = tunstart; 204 #endif 205 ifp->if_flags = IFF_POINTOPOINT; 206 ifp->if_type = IFT_TUNNEL; 207 ifp->if_snd.ifq_maxlen = ifqmaxlen; 208 ifp->if_collisions = 0; 209 ifp->if_ierrors = 0; 210 ifp->if_oerrors = 0; 211 ifp->if_ipackets = 0; 212 ifp->if_opackets = 0; 213 ifp->if_ibytes = 0; 214 ifp->if_obytes = 0; 215 ifp->if_dlt = DLT_NULL; 216 IFQ_SET_READY(&ifp->if_snd); 217 if_attach(ifp); 218 if_alloc_sadl(ifp); 219 bpf_attach(ifp, DLT_NULL, sizeof(uint32_t)); 220 } 221 222 static int 223 tun_clone_destroy(struct ifnet *ifp) 224 { 225 struct tun_softc *tp = (void *)ifp; 226 int s, zombie = 0; 227 228 IF_PURGE(&ifp->if_snd); 229 ifp->if_flags &= ~IFF_RUNNING; 230 231 s = splnet(); 232 simple_lock(&tun_softc_lock); 233 mutex_enter(&tp->tun_lock); 234 LIST_REMOVE(tp, tun_list); 235 if (tp->tun_flags & TUN_OPEN) { 236 /* Hang on to storage until last close */ 237 zombie = 1; 238 tp->tun_flags &= ~TUN_INITED; 239 LIST_INSERT_HEAD(&tunz_softc_list, tp, tun_list); 240 } 241 simple_unlock(&tun_softc_lock); 242 243 if (tp->tun_flags & TUN_RWAIT) { 244 tp->tun_flags &= ~TUN_RWAIT; 245 wakeup((void *)tp); 246 } 247 selnotify(&tp->tun_rsel, 0, 0); 248 249 mutex_exit(&tp->tun_lock); 250 splx(s); 251 252 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 253 fownsignal(tp->tun_pgid, SIGIO, POLL_HUP, 0, NULL); 254 255 bpf_detach(ifp); 256 if_detach(ifp); 257 258 if (!zombie) { 259 seldestroy(&tp->tun_rsel); 260 seldestroy(&tp->tun_wsel); 261 softint_disestablish(tp->tun_osih); 262 softint_disestablish(tp->tun_isih); 263 mutex_destroy(&tp->tun_lock); 264 free(tp, M_DEVBUF); 265 } 266 267 return (0); 268 } 269 270 /* 271 * tunnel open - must be superuser & the device must be 272 * configured in 273 */ 274 static int 275 tunopen(dev_t dev, int flag, int mode, struct lwp *l) 276 { 277 struct ifnet *ifp; 278 struct tun_softc *tp; 279 int s, error; 280 281 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE_TUN, 282 KAUTH_REQ_NETWORK_INTERFACE_TUN_ADD, NULL, NULL, NULL); 283 if (error) 284 return (error); 285 286 s = splnet(); 287 tp = tun_find_unit(dev); 288 289 if (tp == NULL) { 290 (void)tun_clone_create(&tun_cloner, minor(dev)); 291 tp = tun_find_unit(dev); 292 if (tp == NULL) { 293 error = ENXIO; 294 goto out_nolock; 295 } 296 } 297 298 if (tp->tun_flags & TUN_OPEN) { 299 error = EBUSY; 300 goto out; 301 } 302 303 ifp = &tp->tun_if; 304 tp->tun_flags |= TUN_OPEN; 305 TUNDEBUG("%s: open\n", ifp->if_xname); 306 out: 307 mutex_exit(&tp->tun_lock); 308 out_nolock: 309 splx(s); 310 return (error); 311 } 312 313 /* 314 * tunclose - close the device - mark i/f down & delete 315 * routing info 316 */ 317 int 318 tunclose(dev_t dev, int flag, int mode, 319 struct lwp *l) 320 { 321 int s; 322 struct tun_softc *tp; 323 struct ifnet *ifp; 324 325 s = splnet(); 326 if ((tp = tun_find_zunit(minor(dev))) != NULL) { 327 /* interface was "destroyed" before the close */ 328 seldestroy(&tp->tun_rsel); 329 seldestroy(&tp->tun_wsel); 330 softint_disestablish(tp->tun_osih); 331 softint_disestablish(tp->tun_isih); 332 mutex_destroy(&tp->tun_lock); 333 free(tp, M_DEVBUF); 334 goto out_nolock; 335 } 336 337 if ((tp = tun_find_unit(dev)) == NULL) 338 goto out_nolock; 339 340 ifp = &tp->tun_if; 341 342 tp->tun_flags &= ~TUN_OPEN; 343 344 tp->tun_pgid = 0; 345 selnotify(&tp->tun_rsel, 0, 0); 346 347 TUNDEBUG ("%s: closed\n", ifp->if_xname); 348 mutex_exit(&tp->tun_lock); 349 350 /* 351 * junk all pending output 352 */ 353 IFQ_PURGE(&ifp->if_snd); 354 355 if (ifp->if_flags & IFF_UP) { 356 if_down(ifp); 357 if (ifp->if_flags & IFF_RUNNING) { 358 /* find internet addresses and delete routes */ 359 struct ifaddr *ifa; 360 IFADDR_FOREACH(ifa, ifp) { 361 #if defined(INET) || defined(INET6) 362 if (ifa->ifa_addr->sa_family == AF_INET || 363 ifa->ifa_addr->sa_family == AF_INET6) { 364 rtinit(ifa, (int)RTM_DELETE, 365 tp->tun_flags & TUN_DSTADDR 366 ? RTF_HOST 367 : 0); 368 } 369 #endif 370 } 371 } 372 } 373 out_nolock: 374 splx(s); 375 return (0); 376 } 377 378 /* 379 * Call at splnet(). 380 */ 381 static void 382 tuninit(struct tun_softc *tp) 383 { 384 struct ifnet *ifp = &tp->tun_if; 385 struct ifaddr *ifa; 386 387 TUNDEBUG("%s: tuninit\n", ifp->if_xname); 388 389 mutex_enter(&tp->tun_lock); 390 ifp->if_flags |= IFF_UP | IFF_RUNNING; 391 392 tp->tun_flags &= ~(TUN_IASET|TUN_DSTADDR); 393 IFADDR_FOREACH(ifa, ifp) { 394 #ifdef INET 395 if (ifa->ifa_addr->sa_family == AF_INET) { 396 struct sockaddr_in *sin; 397 398 sin = satosin(ifa->ifa_addr); 399 if (sin && sin->sin_addr.s_addr) 400 tp->tun_flags |= TUN_IASET; 401 402 if (ifp->if_flags & IFF_POINTOPOINT) { 403 sin = satosin(ifa->ifa_dstaddr); 404 if (sin && sin->sin_addr.s_addr) 405 tp->tun_flags |= TUN_DSTADDR; 406 } 407 } 408 #endif 409 #ifdef INET6 410 if (ifa->ifa_addr->sa_family == AF_INET6) { 411 struct sockaddr_in6 *sin; 412 413 sin = (struct sockaddr_in6 *)ifa->ifa_addr; 414 if (!IN6_IS_ADDR_UNSPECIFIED(&sin->sin6_addr)) 415 tp->tun_flags |= TUN_IASET; 416 417 if (ifp->if_flags & IFF_POINTOPOINT) { 418 sin = (struct sockaddr_in6 *)ifa->ifa_dstaddr; 419 if (sin && 420 !IN6_IS_ADDR_UNSPECIFIED(&sin->sin6_addr)) 421 tp->tun_flags |= TUN_DSTADDR; 422 } else 423 tp->tun_flags &= ~TUN_DSTADDR; 424 } 425 #endif /* INET6 */ 426 } 427 mutex_exit(&tp->tun_lock); 428 } 429 430 /* 431 * Process an ioctl request. 432 */ 433 static int 434 tun_ioctl(struct ifnet *ifp, u_long cmd, void *data) 435 { 436 int error = 0, s; 437 struct tun_softc *tp = (struct tun_softc *)(ifp->if_softc); 438 struct ifreq *ifr = data; 439 440 s = splnet(); 441 442 switch (cmd) { 443 case SIOCINITIFADDR: 444 tuninit(tp); 445 TUNDEBUG("%s: address set\n", ifp->if_xname); 446 break; 447 case SIOCSIFBRDADDR: 448 TUNDEBUG("%s: broadcast address set\n", ifp->if_xname); 449 break; 450 case SIOCSIFMTU: 451 if (ifr->ifr_mtu > TUNMTU || ifr->ifr_mtu < 576) { 452 error = EINVAL; 453 break; 454 } 455 TUNDEBUG("%s: interface mtu set\n", ifp->if_xname); 456 if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET) 457 error = 0; 458 break; 459 case SIOCADDMULTI: 460 case SIOCDELMULTI: 461 if (ifr == NULL) { 462 error = EAFNOSUPPORT; /* XXX */ 463 break; 464 } 465 switch (ifreq_getaddr(cmd, ifr)->sa_family) { 466 #ifdef INET 467 case AF_INET: 468 break; 469 #endif 470 #ifdef INET6 471 case AF_INET6: 472 break; 473 #endif 474 default: 475 error = EAFNOSUPPORT; 476 break; 477 } 478 break; 479 default: 480 error = ifioctl_common(ifp, cmd, data); 481 } 482 483 splx(s); 484 return (error); 485 } 486 487 /* 488 * tun_output - queue packets from higher level ready to put out. 489 */ 490 static int 491 tun_output(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst, 492 struct rtentry *rt) 493 { 494 struct tun_softc *tp = ifp->if_softc; 495 int s; 496 int error; 497 #if defined(INET) || defined(INET6) 498 int mlen; 499 uint32_t *af; 500 #endif 501 ALTQ_DECL(struct altq_pktattr pktattr;) 502 503 s = splnet(); 504 mutex_enter(&tp->tun_lock); 505 TUNDEBUG ("%s: tun_output\n", ifp->if_xname); 506 507 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 508 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, 509 tp->tun_flags); 510 error = EHOSTDOWN; 511 goto out; 512 } 513 514 /* 515 * if the queueing discipline needs packet classification, 516 * do it before prepending link headers. 517 */ 518 IFQ_CLASSIFY(&ifp->if_snd, m0, dst->sa_family, &pktattr); 519 520 bpf_mtap_af(ifp, dst->sa_family, m0); 521 522 switch(dst->sa_family) { 523 #ifdef INET6 524 case AF_INET6: 525 #endif 526 #ifdef INET 527 case AF_INET: 528 #endif 529 #if defined(INET) || defined(INET6) 530 if (tp->tun_flags & TUN_PREPADDR) { 531 /* Simple link-layer header */ 532 M_PREPEND(m0, dst->sa_len, M_DONTWAIT); 533 if (m0 == NULL) { 534 IF_DROP(&ifp->if_snd); 535 error = ENOBUFS; 536 goto out; 537 } 538 bcopy(dst, mtod(m0, char *), dst->sa_len); 539 } 540 541 if (tp->tun_flags & TUN_IFHEAD) { 542 /* Prepend the address family */ 543 M_PREPEND(m0, sizeof(*af), M_DONTWAIT); 544 if (m0 == NULL) { 545 IF_DROP(&ifp->if_snd); 546 error = ENOBUFS; 547 goto out; 548 } 549 af = mtod(m0,uint32_t *); 550 *af = htonl(dst->sa_family); 551 } else { 552 #ifdef INET 553 if (dst->sa_family != AF_INET) 554 #endif 555 { 556 error = EAFNOSUPPORT; 557 goto out; 558 } 559 } 560 /* FALLTHROUGH */ 561 case AF_UNSPEC: 562 IFQ_ENQUEUE(&ifp->if_snd, m0, &pktattr, error); 563 if (error) { 564 ifp->if_collisions++; 565 error = EAFNOSUPPORT; 566 m0 = NULL; 567 goto out; 568 } 569 mlen = m0->m_pkthdr.len; 570 ifp->if_opackets++; 571 ifp->if_obytes += mlen; 572 break; 573 #endif 574 default: 575 error = EAFNOSUPPORT; 576 goto out; 577 } 578 579 if (tp->tun_flags & TUN_RWAIT) { 580 tp->tun_flags &= ~TUN_RWAIT; 581 wakeup((void *)tp); 582 } 583 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 584 softint_schedule(tp->tun_isih); 585 586 selnotify(&tp->tun_rsel, 0, 0); 587 out: 588 mutex_exit(&tp->tun_lock); 589 splx(s); 590 591 if (error && m0) { 592 m_freem(m0); 593 } 594 return 0; 595 } 596 597 static void 598 tun_i_softintr(void *cookie) 599 { 600 struct tun_softc *tp = cookie; 601 602 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 603 fownsignal(tp->tun_pgid, SIGIO, POLL_IN, POLLIN|POLLRDNORM, 604 NULL); 605 } 606 607 static void 608 tun_o_softintr(void *cookie) 609 { 610 struct tun_softc *tp = cookie; 611 612 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 613 fownsignal(tp->tun_pgid, SIGIO, POLL_OUT, POLLOUT|POLLWRNORM, 614 NULL); 615 } 616 617 /* 618 * the cdevsw interface is now pretty minimal. 619 */ 620 int 621 tunioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) 622 { 623 struct tun_softc *tp; 624 int s, error = 0; 625 626 s = splnet(); 627 tp = tun_find_unit(dev); 628 629 /* interface was "destroyed" already */ 630 if (tp == NULL) { 631 error = ENXIO; 632 goto out_nolock; 633 } 634 635 switch (cmd) { 636 case TUNSDEBUG: 637 tundebug = *(int *)data; 638 break; 639 640 case TUNGDEBUG: 641 *(int *)data = tundebug; 642 break; 643 644 case TUNSIFMODE: 645 switch (*(int *)data & (IFF_POINTOPOINT|IFF_BROADCAST)) { 646 case IFF_POINTOPOINT: 647 case IFF_BROADCAST: 648 if (tp->tun_if.if_flags & IFF_UP) { 649 error = EBUSY; 650 goto out; 651 } 652 tp->tun_if.if_flags &= 653 ~(IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST); 654 tp->tun_if.if_flags |= *(int *)data; 655 break; 656 default: 657 error = EINVAL; 658 goto out; 659 } 660 break; 661 662 case TUNSLMODE: 663 if (*(int *)data) { 664 tp->tun_flags |= TUN_PREPADDR; 665 tp->tun_flags &= ~TUN_IFHEAD; 666 } else 667 tp->tun_flags &= ~TUN_PREPADDR; 668 break; 669 670 case TUNSIFHEAD: 671 if (*(int *)data) { 672 tp->tun_flags |= TUN_IFHEAD; 673 tp->tun_flags &= ~TUN_PREPADDR; 674 } else 675 tp->tun_flags &= ~TUN_IFHEAD; 676 break; 677 678 case TUNGIFHEAD: 679 *(int *)data = (tp->tun_flags & TUN_IFHEAD); 680 break; 681 682 case FIONBIO: 683 if (*(int *)data) 684 tp->tun_flags |= TUN_NBIO; 685 else 686 tp->tun_flags &= ~TUN_NBIO; 687 break; 688 689 case FIOASYNC: 690 if (*(int *)data) 691 tp->tun_flags |= TUN_ASYNC; 692 else 693 tp->tun_flags &= ~TUN_ASYNC; 694 break; 695 696 case FIONREAD: 697 if (tp->tun_if.if_snd.ifq_head) 698 *(int *)data = tp->tun_if.if_snd.ifq_head->m_pkthdr.len; 699 else 700 *(int *)data = 0; 701 break; 702 703 case TIOCSPGRP: 704 case FIOSETOWN: 705 error = fsetown(&tp->tun_pgid, cmd, data); 706 break; 707 708 case TIOCGPGRP: 709 case FIOGETOWN: 710 error = fgetown(tp->tun_pgid, cmd, data); 711 break; 712 713 default: 714 error = ENOTTY; 715 } 716 717 out: 718 mutex_exit(&tp->tun_lock); 719 out_nolock: 720 splx(s); 721 return (error); 722 } 723 724 /* 725 * The cdevsw read interface - reads a packet at a time, or at 726 * least as much of a packet as can be read. 727 */ 728 int 729 tunread(dev_t dev, struct uio *uio, int ioflag) 730 { 731 struct tun_softc *tp; 732 struct ifnet *ifp; 733 struct mbuf *m, *m0; 734 int error = 0, len, s, index; 735 736 s = splnet(); 737 tp = tun_find_unit(dev); 738 739 /* interface was "destroyed" already */ 740 if (tp == NULL) { 741 error = ENXIO; 742 goto out_nolock; 743 } 744 745 index = tp->tun_if.if_index; 746 ifp = &tp->tun_if; 747 748 TUNDEBUG ("%s: read\n", ifp->if_xname); 749 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 750 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, tp->tun_flags); 751 error = EHOSTDOWN; 752 goto out; 753 } 754 755 tp->tun_flags &= ~TUN_RWAIT; 756 757 do { 758 IFQ_DEQUEUE(&ifp->if_snd, m0); 759 if (m0 == 0) { 760 if (tp->tun_flags & TUN_NBIO) { 761 error = EWOULDBLOCK; 762 goto out; 763 } 764 tp->tun_flags |= TUN_RWAIT; 765 if (mtsleep((void *)tp, PZERO|PCATCH|PNORELOCK, 766 "tunread", 0, &tp->tun_lock) != 0) { 767 error = EINTR; 768 goto out_nolock; 769 } else { 770 /* 771 * Maybe the interface was destroyed while 772 * we were sleeping, so let's ensure that 773 * we're looking at the same (valid) tun 774 * interface before looping. 775 */ 776 tp = tun_find_unit(dev); 777 if (tp == NULL) { 778 error = ENXIO; 779 goto out_nolock; 780 } 781 if (tp->tun_if.if_index != index) { 782 error = ENXIO; 783 goto out; 784 } 785 } 786 } 787 } while (m0 == 0); 788 789 mutex_exit(&tp->tun_lock); 790 splx(s); 791 792 /* Copy the mbuf chain */ 793 while (m0 && uio->uio_resid > 0 && error == 0) { 794 len = min(uio->uio_resid, m0->m_len); 795 if (len != 0) 796 error = uiomove(mtod(m0, void *), len, uio); 797 MFREE(m0, m); 798 m0 = m; 799 } 800 801 if (m0) { 802 TUNDEBUG("Dropping mbuf\n"); 803 m_freem(m0); 804 } 805 if (error) 806 ifp->if_ierrors++; 807 808 return (error); 809 810 out: 811 mutex_exit(&tp->tun_lock); 812 out_nolock: 813 splx(s); 814 return (error); 815 } 816 817 /* 818 * the cdevsw write interface - an atomic write is a packet - or else! 819 */ 820 int 821 tunwrite(dev_t dev, struct uio *uio, int ioflag) 822 { 823 struct tun_softc *tp; 824 struct ifnet *ifp; 825 struct mbuf *top, **mp, *m; 826 struct ifqueue *ifq; 827 struct sockaddr dst; 828 int isr, error = 0, s, tlen, mlen; 829 uint32_t family; 830 831 s = splnet(); 832 tp = tun_find_unit(dev); 833 834 /* interface was "destroyed" already */ 835 if (tp == NULL) { 836 error = ENXIO; 837 goto out_nolock; 838 } 839 840 /* Unlock until we've got the data */ 841 mutex_exit(&tp->tun_lock); 842 splx(s); 843 844 ifp = &tp->tun_if; 845 846 TUNDEBUG("%s: tunwrite\n", ifp->if_xname); 847 848 if (tp->tun_flags & TUN_PREPADDR) { 849 if (uio->uio_resid < sizeof(dst)) { 850 error = EIO; 851 goto out0; 852 } 853 error = uiomove((void *)&dst, sizeof(dst), uio); 854 if (dst.sa_len > sizeof(dst)) { 855 /* Duh.. */ 856 char discard; 857 int n = dst.sa_len - sizeof(dst); 858 while (n--) 859 if ((error = uiomove(&discard, 1, uio)) != 0) { 860 goto out0; 861 } 862 } 863 } else if (tp->tun_flags & TUN_IFHEAD) { 864 if (uio->uio_resid < sizeof(family)){ 865 error = EIO; 866 goto out0; 867 } 868 error = uiomove((void *)&family, sizeof(family), uio); 869 dst.sa_family = ntohl(family); 870 } else { 871 #ifdef INET 872 dst.sa_family = AF_INET; 873 #endif 874 } 875 876 if (uio->uio_resid > TUNMTU) { 877 TUNDEBUG("%s: len=%lu!\n", ifp->if_xname, 878 (unsigned long)uio->uio_resid); 879 error = EIO; 880 goto out0; 881 } 882 883 switch (dst.sa_family) { 884 #ifdef INET 885 case AF_INET: 886 ifq = &ipintrq; 887 isr = NETISR_IP; 888 break; 889 #endif 890 #ifdef INET6 891 case AF_INET6: 892 ifq = &ip6intrq; 893 isr = NETISR_IPV6; 894 break; 895 #endif 896 default: 897 error = EAFNOSUPPORT; 898 goto out0; 899 } 900 901 tlen = uio->uio_resid; 902 903 /* get a header mbuf */ 904 MGETHDR(m, M_DONTWAIT, MT_DATA); 905 if (m == NULL) { 906 error = ENOBUFS; 907 goto out0; 908 } 909 mlen = MHLEN; 910 911 top = NULL; 912 mp = ⊤ 913 while (error == 0 && uio->uio_resid > 0) { 914 m->m_len = min(mlen, uio->uio_resid); 915 error = uiomove(mtod(m, void *), m->m_len, uio); 916 *mp = m; 917 mp = &m->m_next; 918 if (error == 0 && uio->uio_resid > 0) { 919 MGET(m, M_DONTWAIT, MT_DATA); 920 if (m == NULL) { 921 error = ENOBUFS; 922 break; 923 } 924 mlen = MLEN; 925 } 926 } 927 if (error) { 928 if (top != NULL) 929 m_freem (top); 930 ifp->if_ierrors++; 931 goto out0; 932 } 933 934 top->m_pkthdr.len = tlen; 935 top->m_pkthdr.rcvif = ifp; 936 937 bpf_mtap_af(ifp, dst.sa_family, top); 938 939 s = splnet(); 940 mutex_enter(&tp->tun_lock); 941 if ((tp->tun_flags & TUN_INITED) == 0) { 942 /* Interface was destroyed */ 943 error = ENXIO; 944 goto out; 945 } 946 if (IF_QFULL(ifq)) { 947 IF_DROP(ifq); 948 ifp->if_collisions++; 949 mutex_exit(&tp->tun_lock); 950 m_freem(top); 951 error = ENOBUFS; 952 goto out_nolock; 953 } 954 955 IF_ENQUEUE(ifq, top); 956 ifp->if_ipackets++; 957 ifp->if_ibytes += tlen; 958 schednetisr(isr); 959 out: 960 mutex_exit(&tp->tun_lock); 961 out_nolock: 962 splx(s); 963 out0: 964 return (error); 965 } 966 967 #ifdef ALTQ 968 /* 969 * Start packet transmission on the interface. 970 * when the interface queue is rate-limited by ALTQ or TBR, 971 * if_start is needed to drain packets from the queue in order 972 * to notify readers when outgoing packets become ready. 973 * 974 * Should be called at splnet. 975 */ 976 static void 977 tunstart(struct ifnet *ifp) 978 { 979 struct tun_softc *tp = ifp->if_softc; 980 981 if (!ALTQ_IS_ENABLED(&ifp->if_snd) && !TBR_IS_ENABLED(&ifp->if_snd)) 982 return; 983 984 mutex_enter(&tp->tun_lock); 985 if (!IF_IS_EMPTY(&ifp->if_snd)) { 986 if (tp->tun_flags & TUN_RWAIT) { 987 tp->tun_flags &= ~TUN_RWAIT; 988 wakeup((void *)tp); 989 } 990 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 991 softint_schedule(tp->tun_osih); 992 993 selnotify(&tp->tun_rsel, 0, 0); 994 } 995 mutex_exit(&tp->tun_lock); 996 } 997 #endif /* ALTQ */ 998 /* 999 * tunpoll - the poll interface, this is only useful on reads 1000 * really. The write detect always returns true, write never blocks 1001 * anyway, it either accepts the packet or drops it. 1002 */ 1003 int 1004 tunpoll(dev_t dev, int events, struct lwp *l) 1005 { 1006 struct tun_softc *tp; 1007 struct ifnet *ifp; 1008 int s, revents = 0; 1009 1010 s = splnet(); 1011 tp = tun_find_unit(dev); 1012 1013 /* interface was "destroyed" already */ 1014 if (tp == NULL) 1015 goto out_nolock; 1016 1017 ifp = &tp->tun_if; 1018 1019 TUNDEBUG("%s: tunpoll\n", ifp->if_xname); 1020 1021 if (events & (POLLIN | POLLRDNORM)) { 1022 if (!IFQ_IS_EMPTY(&ifp->if_snd)) { 1023 TUNDEBUG("%s: tunpoll q=%d\n", ifp->if_xname, 1024 ifp->if_snd.ifq_len); 1025 revents |= events & (POLLIN | POLLRDNORM); 1026 } else { 1027 TUNDEBUG("%s: tunpoll waiting\n", ifp->if_xname); 1028 selrecord(l, &tp->tun_rsel); 1029 } 1030 } 1031 1032 if (events & (POLLOUT | POLLWRNORM)) 1033 revents |= events & (POLLOUT | POLLWRNORM); 1034 1035 mutex_exit(&tp->tun_lock); 1036 out_nolock: 1037 splx(s); 1038 return (revents); 1039 } 1040 1041 static void 1042 filt_tunrdetach(struct knote *kn) 1043 { 1044 struct tun_softc *tp = kn->kn_hook; 1045 int s; 1046 1047 s = splnet(); 1048 SLIST_REMOVE(&tp->tun_rsel.sel_klist, kn, knote, kn_selnext); 1049 splx(s); 1050 } 1051 1052 static int 1053 filt_tunread(struct knote *kn, long hint) 1054 { 1055 struct tun_softc *tp = kn->kn_hook; 1056 struct ifnet *ifp = &tp->tun_if; 1057 struct mbuf *m; 1058 int s; 1059 1060 s = splnet(); 1061 IF_POLL(&ifp->if_snd, m); 1062 if (m == NULL) { 1063 splx(s); 1064 return (0); 1065 } 1066 1067 for (kn->kn_data = 0; m != NULL; m = m->m_next) 1068 kn->kn_data += m->m_len; 1069 1070 splx(s); 1071 return (1); 1072 } 1073 1074 static const struct filterops tunread_filtops = 1075 { 1, NULL, filt_tunrdetach, filt_tunread }; 1076 1077 static const struct filterops tun_seltrue_filtops = 1078 { 1, NULL, filt_tunrdetach, filt_seltrue }; 1079 1080 int 1081 tunkqfilter(dev_t dev, struct knote *kn) 1082 { 1083 struct tun_softc *tp; 1084 struct klist *klist; 1085 int rv = 0, s; 1086 1087 s = splnet(); 1088 tp = tun_find_unit(dev); 1089 if (tp == NULL) 1090 goto out_nolock; 1091 1092 switch (kn->kn_filter) { 1093 case EVFILT_READ: 1094 klist = &tp->tun_rsel.sel_klist; 1095 kn->kn_fop = &tunread_filtops; 1096 break; 1097 1098 case EVFILT_WRITE: 1099 klist = &tp->tun_rsel.sel_klist; 1100 kn->kn_fop = &tun_seltrue_filtops; 1101 break; 1102 1103 default: 1104 rv = EINVAL; 1105 goto out; 1106 } 1107 1108 kn->kn_hook = tp; 1109 1110 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 1111 1112 out: 1113 mutex_exit(&tp->tun_lock); 1114 out_nolock: 1115 splx(s); 1116 return (rv); 1117 } 1118
Indexes created Wed Oct 15 07:09:58 GMT 2025