if_tun.c revision 1.112
1 /* $NetBSD: if_tun.c,v 1.112 2010/01/19 22:08:01 pooka 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 1.112 2010/01/19 22:08:01 pooka 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/cpu.h> 40 41 #include <net/if.h> 42 #include <net/if_types.h> 43 #include <net/netisr.h> 44 #include <net/route.h> 45 46 47 #ifdef INET 48 #include <netinet/in.h> 49 #include <netinet/in_systm.h> 50 #include <netinet/in_var.h> 51 #include <netinet/ip.h> 52 #include <netinet/if_inarp.h> 53 #endif 54 55 56 #include <sys/time.h> 57 #include <net/bpf.h> 58 59 #include <net/if_tun.h> 60 61 #define TUNDEBUG if (tundebug) printf 62 int tundebug = 0; 63 64 extern int ifqmaxlen; 65 void tunattach(int); 66 67 static LIST_HEAD(, tun_softc) tun_softc_list; 68 static LIST_HEAD(, tun_softc) tunz_softc_list; 69 static struct simplelock tun_softc_lock; 70 71 static int tun_ioctl(struct ifnet *, u_long, void *); 72 static int tun_output(struct ifnet *, struct mbuf *, 73 const struct sockaddr *, struct rtentry *rt); 74 static int tun_clone_create(struct if_clone *, int); 75 static int tun_clone_destroy(struct ifnet *); 76 77 static struct if_clone tun_cloner = 78 IF_CLONE_INITIALIZER("tun", tun_clone_create, tun_clone_destroy); 79 80 static void tunattach0(struct tun_softc *); 81 static void tuninit(struct tun_softc *); 82 static void tun_i_softintr(void *); 83 static void tun_o_softintr(void *); 84 #ifdef ALTQ 85 static void tunstart(struct ifnet *); 86 #endif 87 static struct tun_softc *tun_find_unit(dev_t); 88 static struct tun_softc *tun_find_zunit(int); 89 90 static dev_type_open(tunopen); 91 static dev_type_close(tunclose); 92 static dev_type_read(tunread); 93 static dev_type_write(tunwrite); 94 static dev_type_ioctl(tunioctl); 95 static dev_type_poll(tunpoll); 96 static dev_type_kqfilter(tunkqfilter); 97 98 const struct cdevsw tun_cdevsw = { 99 tunopen, tunclose, tunread, tunwrite, tunioctl, 100 nostop, notty, tunpoll, nommap, tunkqfilter, D_OTHER, 101 }; 102 103 void 104 tunattach(int unused) 105 { 106 107 simple_lock_init(&tun_softc_lock); 108 LIST_INIT(&tun_softc_list); 109 LIST_INIT(&tunz_softc_list); 110 if_clone_attach(&tun_cloner); 111 } 112 113 /* 114 * Find driver instance from dev_t. 115 * Call at splnet(). 116 * Returns with tp locked (if found). 117 */ 118 static struct tun_softc * 119 tun_find_unit(dev_t dev) 120 { 121 struct tun_softc *tp; 122 int unit = minor(dev); 123 124 simple_lock(&tun_softc_lock); 125 LIST_FOREACH(tp, &tun_softc_list, tun_list) 126 if (unit == tp->tun_unit) 127 break; 128 if (tp) 129 simple_lock(&tp->tun_lock); 130 simple_unlock(&tun_softc_lock); 131 132 return (tp); 133 } 134 135 /* 136 * Find zombie driver instance by unit number. 137 * Call at splnet(). 138 * Remove tp from list and return it unlocked (if found). 139 */ 140 static struct tun_softc * 141 tun_find_zunit(int unit) 142 { 143 struct tun_softc *tp; 144 145 simple_lock(&tun_softc_lock); 146 LIST_FOREACH(tp, &tunz_softc_list, tun_list) 147 if (unit == tp->tun_unit) 148 break; 149 if (tp) 150 LIST_REMOVE(tp, tun_list); 151 simple_unlock(&tun_softc_lock); 152 #ifdef DIAGNOSTIC 153 if (tp != NULL && (tp->tun_flags & (TUN_INITED|TUN_OPEN)) != TUN_OPEN) 154 printf("tun%d: inconsistent flags: %x\n", unit, tp->tun_flags); 155 #endif 156 157 return (tp); 158 } 159 160 static int 161 tun_clone_create(struct if_clone *ifc, int unit) 162 { 163 struct tun_softc *tp; 164 165 if ((tp = tun_find_zunit(unit)) == NULL) { 166 /* Allocate a new instance */ 167 tp = malloc(sizeof(*tp), M_DEVBUF, M_WAITOK|M_ZERO); 168 169 tp->tun_unit = unit; 170 simple_lock_init(&tp->tun_lock); 171 selinit(&tp->tun_rsel); 172 selinit(&tp->tun_wsel); 173 } else { 174 /* Revive tunnel instance; clear ifp part */ 175 (void)memset(&tp->tun_if, 0, sizeof(struct ifnet)); 176 } 177 178 if_initname(&tp->tun_if, ifc->ifc_name, unit); 179 tunattach0(tp); 180 tp->tun_flags |= TUN_INITED; 181 tp->tun_osih = softint_establish(SOFTINT_CLOCK, tun_o_softintr, tp); 182 tp->tun_isih = softint_establish(SOFTINT_CLOCK, tun_i_softintr, tp); 183 184 simple_lock(&tun_softc_lock); 185 LIST_INSERT_HEAD(&tun_softc_list, tp, tun_list); 186 simple_unlock(&tun_softc_lock); 187 188 return (0); 189 } 190 191 static void 192 tunattach0(struct tun_softc *tp) 193 { 194 struct ifnet *ifp; 195 196 ifp = &tp->tun_if; 197 ifp->if_softc = tp; 198 ifp->if_mtu = TUNMTU; 199 ifp->if_ioctl = tun_ioctl; 200 ifp->if_output = tun_output; 201 #ifdef ALTQ 202 ifp->if_start = tunstart; 203 #endif 204 ifp->if_flags = IFF_POINTOPOINT; 205 ifp->if_type = IFT_TUNNEL; 206 ifp->if_snd.ifq_maxlen = ifqmaxlen; 207 ifp->if_collisions = 0; 208 ifp->if_ierrors = 0; 209 ifp->if_oerrors = 0; 210 ifp->if_ipackets = 0; 211 ifp->if_opackets = 0; 212 ifp->if_ibytes = 0; 213 ifp->if_obytes = 0; 214 ifp->if_dlt = DLT_NULL; 215 IFQ_SET_READY(&ifp->if_snd); 216 if_attach(ifp); 217 if_alloc_sadl(ifp); 218 bpf_ops->bpf_attach(ifp, DLT_NULL, sizeof(uint32_t), &ifp->if_bpf); 219 } 220 221 static int 222 tun_clone_destroy(struct ifnet *ifp) 223 { 224 struct tun_softc *tp = (void *)ifp; 225 int s, zombie = 0; 226 227 s = splnet(); 228 simple_lock(&tun_softc_lock); 229 simple_lock(&tp->tun_lock); 230 LIST_REMOVE(tp, tun_list); 231 if (tp->tun_flags & TUN_OPEN) { 232 /* Hang on to storage until last close */ 233 zombie = 1; 234 tp->tun_flags &= ~TUN_INITED; 235 LIST_INSERT_HEAD(&tunz_softc_list, tp, tun_list); 236 } 237 simple_unlock(&tun_softc_lock); 238 239 IF_PURGE(&ifp->if_snd); 240 ifp->if_flags &= ~IFF_RUNNING; 241 242 if (tp->tun_flags & TUN_RWAIT) { 243 tp->tun_flags &= ~TUN_RWAIT; 244 wakeup((void *)tp); 245 } 246 selnotify(&tp->tun_rsel, 0, 0); 247 248 simple_unlock(&tp->tun_lock); 249 splx(s); 250 251 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 252 fownsignal(tp->tun_pgid, SIGIO, POLL_HUP, 0, NULL); 253 254 bpf_ops->bpf_detach(ifp); 255 if_detach(ifp); 256 257 if (!zombie) { 258 seldestroy(&tp->tun_rsel); 259 seldestroy(&tp->tun_wsel); 260 softint_disestablish(tp->tun_osih); 261 softint_disestablish(tp->tun_isih); 262 free(tp, M_DEVBUF); 263 } 264 265 return (0); 266 } 267 268 /* 269 * tunnel open - must be superuser & the device must be 270 * configured in 271 */ 272 static int 273 tunopen(dev_t dev, int flag, int mode, struct lwp *l) 274 { 275 struct ifnet *ifp; 276 struct tun_softc *tp; 277 int s, error; 278 279 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE_TUN, 280 KAUTH_REQ_NETWORK_INTERFACE_TUN_ADD, NULL, NULL, NULL); 281 if (error) 282 return (error); 283 284 s = splnet(); 285 tp = tun_find_unit(dev); 286 287 if (tp == NULL) { 288 (void)tun_clone_create(&tun_cloner, minor(dev)); 289 tp = tun_find_unit(dev); 290 if (tp == NULL) { 291 error = ENXIO; 292 goto out_nolock; 293 } 294 } 295 296 if (tp->tun_flags & TUN_OPEN) { 297 error = EBUSY; 298 goto out; 299 } 300 301 ifp = &tp->tun_if; 302 tp->tun_flags |= TUN_OPEN; 303 TUNDEBUG("%s: open\n", ifp->if_xname); 304 out: 305 simple_unlock(&tp->tun_lock); 306 out_nolock: 307 splx(s); 308 return (error); 309 } 310 311 /* 312 * tunclose - close the device - mark i/f down & delete 313 * routing info 314 */ 315 int 316 tunclose(dev_t dev, int flag, int mode, 317 struct lwp *l) 318 { 319 int s; 320 struct tun_softc *tp; 321 struct ifnet *ifp; 322 323 s = splnet(); 324 if ((tp = tun_find_zunit(minor(dev))) != NULL) { 325 /* interface was "destroyed" before the close */ 326 seldestroy(&tp->tun_rsel); 327 seldestroy(&tp->tun_wsel); 328 softint_disestablish(tp->tun_osih); 329 softint_disestablish(tp->tun_isih); 330 free(tp, M_DEVBUF); 331 goto out_nolock; 332 } 333 334 if ((tp = tun_find_unit(dev)) == NULL) 335 goto out_nolock; 336 337 ifp = &tp->tun_if; 338 339 tp->tun_flags &= ~TUN_OPEN; 340 341 /* 342 * junk all pending output 343 */ 344 IFQ_PURGE(&ifp->if_snd); 345 346 if (ifp->if_flags & IFF_UP) { 347 if_down(ifp); 348 if (ifp->if_flags & IFF_RUNNING) { 349 /* find internet addresses and delete routes */ 350 struct ifaddr *ifa; 351 IFADDR_FOREACH(ifa, ifp) { 352 #if defined(INET) || defined(INET6) 353 if (ifa->ifa_addr->sa_family == AF_INET || 354 ifa->ifa_addr->sa_family == AF_INET6) { 355 rtinit(ifa, (int)RTM_DELETE, 356 tp->tun_flags & TUN_DSTADDR 357 ? RTF_HOST 358 : 0); 359 } 360 #endif 361 } 362 } 363 } 364 tp->tun_pgid = 0; 365 selnotify(&tp->tun_rsel, 0, 0); 366 367 TUNDEBUG ("%s: closed\n", ifp->if_xname); 368 simple_unlock(&tp->tun_lock); 369 out_nolock: 370 splx(s); 371 return (0); 372 } 373 374 /* 375 * Call at splnet(). 376 */ 377 static void 378 tuninit(struct tun_softc *tp) 379 { 380 struct ifnet *ifp = &tp->tun_if; 381 struct ifaddr *ifa; 382 383 TUNDEBUG("%s: tuninit\n", ifp->if_xname); 384 385 simple_lock(&tp->tun_lock); 386 ifp->if_flags |= IFF_UP | IFF_RUNNING; 387 388 tp->tun_flags &= ~(TUN_IASET|TUN_DSTADDR); 389 IFADDR_FOREACH(ifa, ifp) { 390 #ifdef INET 391 if (ifa->ifa_addr->sa_family == AF_INET) { 392 struct sockaddr_in *sin; 393 394 sin = satosin(ifa->ifa_addr); 395 if (sin && sin->sin_addr.s_addr) 396 tp->tun_flags |= TUN_IASET; 397 398 if (ifp->if_flags & IFF_POINTOPOINT) { 399 sin = satosin(ifa->ifa_dstaddr); 400 if (sin && sin->sin_addr.s_addr) 401 tp->tun_flags |= TUN_DSTADDR; 402 } 403 } 404 #endif 405 #ifdef INET6 406 if (ifa->ifa_addr->sa_family == AF_INET6) { 407 struct sockaddr_in6 *sin; 408 409 sin = (struct sockaddr_in6 *)ifa->ifa_addr; 410 if (!IN6_IS_ADDR_UNSPECIFIED(&sin->sin6_addr)) 411 tp->tun_flags |= TUN_IASET; 412 413 if (ifp->if_flags & IFF_POINTOPOINT) { 414 sin = (struct sockaddr_in6 *)ifa->ifa_dstaddr; 415 if (sin && 416 !IN6_IS_ADDR_UNSPECIFIED(&sin->sin6_addr)) 417 tp->tun_flags |= TUN_DSTADDR; 418 } else 419 tp->tun_flags &= ~TUN_DSTADDR; 420 } 421 #endif /* INET6 */ 422 } 423 424 simple_unlock(&tp->tun_lock); 425 return; 426 } 427 428 /* 429 * Process an ioctl request. 430 */ 431 static int 432 tun_ioctl(struct ifnet *ifp, u_long cmd, void *data) 433 { 434 int error = 0, s; 435 struct tun_softc *tp = (struct tun_softc *)(ifp->if_softc); 436 struct ifreq *ifr = data; 437 438 s = splnet(); 439 440 switch (cmd) { 441 case SIOCINITIFADDR: 442 tuninit(tp); 443 TUNDEBUG("%s: address set\n", ifp->if_xname); 444 break; 445 case SIOCSIFDSTADDR: 446 tuninit(tp); 447 TUNDEBUG("%s: destination address set\n", ifp->if_xname); 448 break; 449 case SIOCSIFBRDADDR: 450 TUNDEBUG("%s: broadcast address set\n", ifp->if_xname); 451 break; 452 case SIOCSIFMTU: 453 if (ifr->ifr_mtu > TUNMTU || ifr->ifr_mtu < 576) { 454 error = EINVAL; 455 break; 456 } 457 TUNDEBUG("%s: interface mtu set\n", ifp->if_xname); 458 if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET) 459 error = 0; 460 break; 461 case SIOCADDMULTI: 462 case SIOCDELMULTI: 463 if (ifr == NULL) { 464 error = EAFNOSUPPORT; /* XXX */ 465 break; 466 } 467 switch (ifreq_getaddr(cmd, ifr)->sa_family) { 468 #ifdef INET 469 case AF_INET: 470 break; 471 #endif 472 #ifdef INET6 473 case AF_INET6: 474 break; 475 #endif 476 default: 477 error = EAFNOSUPPORT; 478 break; 479 } 480 break; 481 default: 482 error = ifioctl_common(ifp, cmd, data); 483 } 484 485 splx(s); 486 return (error); 487 } 488 489 /* 490 * tun_output - queue packets from higher level ready to put out. 491 */ 492 static int 493 tun_output(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst, 494 struct rtentry *rt) 495 { 496 struct tun_softc *tp = ifp->if_softc; 497 int s; 498 int error; 499 #if defined(INET) || defined(INET6) 500 int mlen; 501 uint32_t *af; 502 #endif 503 ALTQ_DECL(struct altq_pktattr pktattr;) 504 505 s = splnet(); 506 simple_lock(&tp->tun_lock); 507 TUNDEBUG ("%s: tun_output\n", ifp->if_xname); 508 509 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 510 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, 511 tp->tun_flags); 512 m_freem (m0); 513 error = EHOSTDOWN; 514 goto out; 515 } 516 517 /* 518 * if the queueing discipline needs packet classification, 519 * do it before prepending link headers. 520 */ 521 IFQ_CLASSIFY(&ifp->if_snd, m0, dst->sa_family, &pktattr); 522 523 if (ifp->if_bpf) 524 bpf_ops->bpf_mtap_af(ifp->if_bpf, 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 m_freem(m0); 561 error = EAFNOSUPPORT; 562 goto out; 563 } 564 } 565 /* FALLTHROUGH */ 566 case AF_UNSPEC: 567 IFQ_ENQUEUE(&ifp->if_snd, m0, &pktattr, error); 568 if (error) { 569 ifp->if_collisions++; 570 error = EAFNOSUPPORT; 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 m_freem(m0); 580 error = EAFNOSUPPORT; 581 goto out; 582 } 583 584 if (tp->tun_flags & TUN_RWAIT) { 585 tp->tun_flags &= ~TUN_RWAIT; 586 wakeup((void *)tp); 587 } 588 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 589 softint_schedule(tp->tun_isih); 590 591 selnotify(&tp->tun_rsel, 0, 0); 592 out: 593 simple_unlock(&tp->tun_lock); 594 splx(s); 595 return (0); 596 } 597 598 static void 599 tun_i_softintr(void *cookie) 600 { 601 struct tun_softc *tp = cookie; 602 603 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 604 fownsignal(tp->tun_pgid, SIGIO, POLL_IN, POLLIN|POLLRDNORM, 605 NULL); 606 } 607 608 static void 609 tun_o_softintr(void *cookie) 610 { 611 struct tun_softc *tp = cookie; 612 613 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 614 fownsignal(tp->tun_pgid, SIGIO, POLL_OUT, POLLOUT|POLLWRNORM, 615 NULL); 616 } 617 618 /* 619 * the cdevsw interface is now pretty minimal. 620 */ 621 int 622 tunioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) 623 { 624 struct tun_softc *tp; 625 int s, error = 0; 626 627 s = splnet(); 628 tp = tun_find_unit(dev); 629 630 /* interface was "destroyed" already */ 631 if (tp == NULL) { 632 error = ENXIO; 633 goto out_nolock; 634 } 635 636 switch (cmd) { 637 case TUNSDEBUG: 638 tundebug = *(int *)data; 639 break; 640 641 case TUNGDEBUG: 642 *(int *)data = tundebug; 643 break; 644 645 case TUNSIFMODE: 646 switch (*(int *)data & (IFF_POINTOPOINT|IFF_BROADCAST)) { 647 case IFF_POINTOPOINT: 648 case IFF_BROADCAST: 649 if (tp->tun_if.if_flags & IFF_UP) { 650 error = EBUSY; 651 goto out; 652 } 653 tp->tun_if.if_flags &= 654 ~(IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST); 655 tp->tun_if.if_flags |= *(int *)data; 656 break; 657 default: 658 error = EINVAL; 659 goto out; 660 } 661 break; 662 663 case TUNSLMODE: 664 if (*(int *)data) { 665 tp->tun_flags |= TUN_PREPADDR; 666 tp->tun_flags &= ~TUN_IFHEAD; 667 } else 668 tp->tun_flags &= ~TUN_PREPADDR; 669 break; 670 671 case TUNSIFHEAD: 672 if (*(int *)data) { 673 tp->tun_flags |= TUN_IFHEAD; 674 tp->tun_flags &= ~TUN_PREPADDR; 675 } else 676 tp->tun_flags &= ~TUN_IFHEAD; 677 break; 678 679 case TUNGIFHEAD: 680 *(int *)data = (tp->tun_flags & TUN_IFHEAD); 681 break; 682 683 case FIONBIO: 684 if (*(int *)data) 685 tp->tun_flags |= TUN_NBIO; 686 else 687 tp->tun_flags &= ~TUN_NBIO; 688 break; 689 690 case FIOASYNC: 691 if (*(int *)data) 692 tp->tun_flags |= TUN_ASYNC; 693 else 694 tp->tun_flags &= ~TUN_ASYNC; 695 break; 696 697 case FIONREAD: 698 if (tp->tun_if.if_snd.ifq_head) 699 *(int *)data = tp->tun_if.if_snd.ifq_head->m_pkthdr.len; 700 else 701 *(int *)data = 0; 702 break; 703 704 case TIOCSPGRP: 705 case FIOSETOWN: 706 error = fsetown(&tp->tun_pgid, cmd, data); 707 break; 708 709 case TIOCGPGRP: 710 case FIOGETOWN: 711 error = fgetown(tp->tun_pgid, cmd, data); 712 break; 713 714 default: 715 error = ENOTTY; 716 } 717 718 out: 719 simple_unlock(&tp->tun_lock); 720 out_nolock: 721 splx(s); 722 return (error); 723 } 724 725 /* 726 * The cdevsw read interface - reads a packet at a time, or at 727 * least as much of a packet as can be read. 728 */ 729 int 730 tunread(dev_t dev, struct uio *uio, int ioflag) 731 { 732 struct tun_softc *tp; 733 struct ifnet *ifp; 734 struct mbuf *m, *m0; 735 int error = 0, len, s, index; 736 737 s = splnet(); 738 tp = tun_find_unit(dev); 739 740 /* interface was "destroyed" already */ 741 if (tp == NULL) { 742 error = ENXIO; 743 goto out_nolock; 744 } 745 746 index = tp->tun_if.if_index; 747 ifp = &tp->tun_if; 748 749 TUNDEBUG ("%s: read\n", ifp->if_xname); 750 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 751 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, tp->tun_flags); 752 error = EHOSTDOWN; 753 goto out; 754 } 755 756 tp->tun_flags &= ~TUN_RWAIT; 757 758 do { 759 IFQ_DEQUEUE(&ifp->if_snd, m0); 760 if (m0 == 0) { 761 if (tp->tun_flags & TUN_NBIO) { 762 error = EWOULDBLOCK; 763 goto out; 764 } 765 tp->tun_flags |= TUN_RWAIT; 766 if (ltsleep((void *)tp, PZERO|PCATCH|PNORELOCK, 767 "tunread", 0, &tp->tun_lock) != 0) { 768 error = EINTR; 769 goto out_nolock; 770 } else { 771 /* 772 * Maybe the interface was destroyed while 773 * we were sleeping, so let's ensure that 774 * we're looking at the same (valid) tun 775 * interface before looping. 776 */ 777 tp = tun_find_unit(dev); 778 if (tp == NULL) { 779 error = ENXIO; 780 goto out_nolock; 781 } 782 if (tp->tun_if.if_index != index) { 783 error = ENXIO; 784 goto out; 785 } 786 } 787 } 788 } while (m0 == 0); 789 790 simple_unlock(&tp->tun_lock); 791 splx(s); 792 793 /* Copy the mbuf chain */ 794 while (m0 && uio->uio_resid > 0 && error == 0) { 795 len = min(uio->uio_resid, m0->m_len); 796 if (len != 0) 797 error = uiomove(mtod(m0, void *), len, uio); 798 MFREE(m0, m); 799 m0 = m; 800 } 801 802 if (m0) { 803 TUNDEBUG("Dropping mbuf\n"); 804 m_freem(m0); 805 } 806 if (error) 807 ifp->if_ierrors++; 808 809 return (error); 810 811 out: 812 simple_unlock(&tp->tun_lock); 813 out_nolock: 814 splx(s); 815 return (error); 816 } 817 818 /* 819 * the cdevsw write interface - an atomic write is a packet - or else! 820 */ 821 int 822 tunwrite(dev_t dev, struct uio *uio, int ioflag) 823 { 824 struct tun_softc *tp; 825 struct ifnet *ifp; 826 struct mbuf *top, **mp, *m; 827 struct ifqueue *ifq; 828 struct sockaddr dst; 829 int isr, error = 0, s, tlen, mlen; 830 uint32_t family; 831 832 s = splnet(); 833 tp = tun_find_unit(dev); 834 835 /* interface was "destroyed" already */ 836 if (tp == NULL) { 837 error = ENXIO; 838 goto out_nolock; 839 } 840 841 /* Unlock until we've got the data */ 842 simple_unlock(&tp->tun_lock); 843 splx(s); 844 845 ifp = &tp->tun_if; 846 847 TUNDEBUG("%s: tunwrite\n", ifp->if_xname); 848 849 if (tp->tun_flags & TUN_PREPADDR) { 850 if (uio->uio_resid < sizeof(dst)) { 851 error = EIO; 852 goto out0; 853 } 854 error = uiomove((void *)&dst, sizeof(dst), uio); 855 if (dst.sa_len > sizeof(dst)) { 856 /* Duh.. */ 857 char discard; 858 int n = dst.sa_len - sizeof(dst); 859 while (n--) 860 if ((error = uiomove(&discard, 1, uio)) != 0) { 861 goto out0; 862 } 863 } 864 } else if (tp->tun_flags & TUN_IFHEAD) { 865 if (uio->uio_resid < sizeof(family)){ 866 error = EIO; 867 goto out0; 868 } 869 error = uiomove((void *)&family, sizeof(family), uio); 870 dst.sa_family = ntohl(family); 871 } else { 872 #ifdef INET 873 dst.sa_family = AF_INET; 874 #endif 875 } 876 877 if (uio->uio_resid > TUNMTU) { 878 TUNDEBUG("%s: len=%lu!\n", ifp->if_xname, 879 (unsigned long)uio->uio_resid); 880 error = EIO; 881 goto out0; 882 } 883 884 switch (dst.sa_family) { 885 #ifdef INET 886 case AF_INET: 887 ifq = &ipintrq; 888 isr = NETISR_IP; 889 break; 890 #endif 891 #ifdef INET6 892 case AF_INET6: 893 ifq = &ip6intrq; 894 isr = NETISR_IPV6; 895 break; 896 #endif 897 default: 898 error = EAFNOSUPPORT; 899 goto out0; 900 } 901 902 tlen = uio->uio_resid; 903 904 /* get a header mbuf */ 905 MGETHDR(m, M_DONTWAIT, MT_DATA); 906 if (m == NULL) { 907 error = ENOBUFS; 908 goto out0; 909 } 910 mlen = MHLEN; 911 912 top = NULL; 913 mp = ⊤ 914 while (error == 0 && uio->uio_resid > 0) { 915 m->m_len = min(mlen, uio->uio_resid); 916 error = uiomove(mtod(m, void *), m->m_len, uio); 917 *mp = m; 918 mp = &m->m_next; 919 if (error == 0 && uio->uio_resid > 0) { 920 MGET(m, M_DONTWAIT, MT_DATA); 921 if (m == NULL) { 922 error = ENOBUFS; 923 break; 924 } 925 mlen = MLEN; 926 } 927 } 928 if (error) { 929 if (top != NULL) 930 m_freem (top); 931 ifp->if_ierrors++; 932 goto out0; 933 } 934 935 top->m_pkthdr.len = tlen; 936 top->m_pkthdr.rcvif = ifp; 937 938 if (ifp->if_bpf) 939 bpf_ops->bpf_mtap_af(ifp->if_bpf, dst.sa_family, top); 940 941 s = splnet(); 942 simple_lock(&tp->tun_lock); 943 if ((tp->tun_flags & TUN_INITED) == 0) { 944 /* Interface was destroyed */ 945 error = ENXIO; 946 goto out; 947 } 948 if (IF_QFULL(ifq)) { 949 IF_DROP(ifq); 950 ifp->if_collisions++; 951 m_freem(top); 952 error = ENOBUFS; 953 goto out; 954 } 955 956 IF_ENQUEUE(ifq, top); 957 ifp->if_ipackets++; 958 ifp->if_ibytes += tlen; 959 schednetisr(isr); 960 out: 961 simple_unlock(&tp->tun_lock); 962 out_nolock: 963 splx(s); 964 out0: 965 return (error); 966 } 967 968 #ifdef ALTQ 969 /* 970 * Start packet transmission on the interface. 971 * when the interface queue is rate-limited by ALTQ or TBR, 972 * if_start is needed to drain packets from the queue in order 973 * to notify readers when outgoing packets become ready. 974 * 975 * Should be called at splnet. 976 */ 977 static void 978 tunstart(struct ifnet *ifp) 979 { 980 struct tun_softc *tp = ifp->if_softc; 981 982 if (!ALTQ_IS_ENABLED(&ifp->if_snd) && !TBR_IS_ENABLED(&ifp->if_snd)) 983 return; 984 985 simple_lock(&tp->tun_lock); 986 if (!IF_IS_EMPTY(&ifp->if_snd)) { 987 if (tp->tun_flags & TUN_RWAIT) { 988 tp->tun_flags &= ~TUN_RWAIT; 989 wakeup((void *)tp); 990 } 991 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 992 softint_schedule(tp->tun_osih); 993 994 selnotify(&tp->tun_rsel, 0, 0); 995 } 996 simple_unlock(&tp->tun_lock); 997 } 998 #endif /* ALTQ */ 999 /* 1000 * tunpoll - the poll interface, this is only useful on reads 1001 * really. The write detect always returns true, write never blocks 1002 * anyway, it either accepts the packet or drops it. 1003 */ 1004 int 1005 tunpoll(dev_t dev, int events, struct lwp *l) 1006 { 1007 struct tun_softc *tp; 1008 struct ifnet *ifp; 1009 int s, revents = 0; 1010 1011 s = splnet(); 1012 tp = tun_find_unit(dev); 1013 1014 /* interface was "destroyed" already */ 1015 if (tp == NULL) 1016 goto out_nolock; 1017 1018 ifp = &tp->tun_if; 1019 1020 TUNDEBUG("%s: tunpoll\n", ifp->if_xname); 1021 1022 if (events & (POLLIN | POLLRDNORM)) { 1023 if (!IFQ_IS_EMPTY(&ifp->if_snd)) { 1024 TUNDEBUG("%s: tunpoll q=%d\n", ifp->if_xname, 1025 ifp->if_snd.ifq_len); 1026 revents |= events & (POLLIN | POLLRDNORM); 1027 } else { 1028 TUNDEBUG("%s: tunpoll waiting\n", ifp->if_xname); 1029 selrecord(l, &tp->tun_rsel); 1030 } 1031 } 1032 1033 if (events & (POLLOUT | POLLWRNORM)) 1034 revents |= events & (POLLOUT | POLLWRNORM); 1035 1036 simple_unlock(&tp->tun_lock); 1037 out_nolock: 1038 splx(s); 1039 return (revents); 1040 } 1041 1042 static void 1043 filt_tunrdetach(struct knote *kn) 1044 { 1045 struct tun_softc *tp = kn->kn_hook; 1046 int s; 1047 1048 s = splnet(); 1049 SLIST_REMOVE(&tp->tun_rsel.sel_klist, kn, knote, kn_selnext); 1050 splx(s); 1051 } 1052 1053 static int 1054 filt_tunread(struct knote *kn, long hint) 1055 { 1056 struct tun_softc *tp = kn->kn_hook; 1057 struct ifnet *ifp = &tp->tun_if; 1058 struct mbuf *m; 1059 int s; 1060 1061 s = splnet(); 1062 IF_POLL(&ifp->if_snd, m); 1063 if (m == NULL) { 1064 splx(s); 1065 return (0); 1066 } 1067 1068 for (kn->kn_data = 0; m != NULL; m = m->m_next) 1069 kn->kn_data += m->m_len; 1070 1071 splx(s); 1072 return (1); 1073 } 1074 1075 static const struct filterops tunread_filtops = 1076 { 1, NULL, filt_tunrdetach, filt_tunread }; 1077 1078 static const struct filterops tun_seltrue_filtops = 1079 { 1, NULL, filt_tunrdetach, filt_seltrue }; 1080 1081 int 1082 tunkqfilter(dev_t dev, struct knote *kn) 1083 { 1084 struct tun_softc *tp; 1085 struct klist *klist; 1086 int rv = 0, s; 1087 1088 s = splnet(); 1089 tp = tun_find_unit(dev); 1090 if (tp == NULL) 1091 goto out_nolock; 1092 1093 switch (kn->kn_filter) { 1094 case EVFILT_READ: 1095 klist = &tp->tun_rsel.sel_klist; 1096 kn->kn_fop = &tunread_filtops; 1097 break; 1098 1099 case EVFILT_WRITE: 1100 klist = &tp->tun_rsel.sel_klist; 1101 kn->kn_fop = &tun_seltrue_filtops; 1102 break; 1103 1104 default: 1105 rv = EINVAL; 1106 goto out; 1107 } 1108 1109 kn->kn_hook = tp; 1110 1111 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 1112 1113 out: 1114 simple_unlock(&tp->tun_lock); 1115 out_nolock: 1116 splx(s); 1117 return (rv); 1118 } 1119
Indexes created Tue Oct 14 01:09:49 GMT 2025