1 /* $NetBSD: if_tun.c,v 1.78 2005/12/11 23:05:25 thorpej 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 1.78 2005/12/11 23:05:25 thorpej Exp $"); 19 20 #include "opt_inet.h" 21 #include "opt_ns.h" 22 23 #include <sys/param.h> 24 #include <sys/proc.h> 25 #include <sys/systm.h> 26 #include <sys/mbuf.h> 27 #include <sys/buf.h> 28 #include <sys/protosw.h> 29 #include <sys/socket.h> 30 #include <sys/ioctl.h> 31 #include <sys/errno.h> 32 #include <sys/syslog.h> 33 #include <sys/select.h> 34 #include <sys/poll.h> 35 #include <sys/file.h> 36 #include <sys/signalvar.h> 37 #include <sys/conf.h> 38 39 #include <machine/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 #ifdef NS 56 #include <netns/ns.h> 57 #include <netns/ns_if.h> 58 #endif 59 60 #include "bpfilter.h" 61 #if NBPFILTER > 0 62 #include <sys/time.h> 63 #include <net/bpf.h> 64 #endif 65 66 #include <net/if_tun.h> 67 68 #define TUNDEBUG if (tundebug) printf 69 int tundebug = 0; 70 71 extern int ifqmaxlen; 72 void tunattach(int); 73 74 static LIST_HEAD(, tun_softc) tun_softc_list; 75 static LIST_HEAD(, tun_softc) tunz_softc_list; 76 static struct simplelock tun_softc_lock; 77 78 static int tun_ioctl(struct ifnet *, u_long, caddr_t); 79 static int tun_output(struct ifnet *, struct mbuf *, struct sockaddr *, 80 struct rtentry *rt); 81 static int tun_clone_create(struct if_clone *, int); 82 static int tun_clone_destroy(struct ifnet *); 83 84 static struct if_clone tun_cloner = 85 IF_CLONE_INITIALIZER("tun", tun_clone_create, tun_clone_destroy); 86 87 static void tunattach0(struct tun_softc *); 88 static void tuninit(struct tun_softc *); 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 tunopen, tunclose, tunread, tunwrite, tunioctl, 105 nostop, notty, tunpoll, nommap, tunkqfilter, 106 }; 107 108 void 109 tunattach(int unused) 110 { 111 112 simple_lock_init(&tun_softc_lock); 113 LIST_INIT(&tun_softc_list); 114 LIST_INIT(&tunz_softc_list); 115 if_clone_attach(&tun_cloner); 116 } 117 118 /* 119 * Find driver instance from dev_t. 120 * Call at splnet(). 121 * Returns with tp locked (if found). 122 */ 123 static struct tun_softc * 124 tun_find_unit(dev_t dev) 125 { 126 struct tun_softc *tp; 127 int unit = minor(dev); 128 129 simple_lock(&tun_softc_lock); 130 LIST_FOREACH(tp, &tun_softc_list, tun_list) 131 if (unit == tp->tun_unit) 132 break; 133 if (tp) 134 simple_lock(&tp->tun_lock); 135 simple_unlock(&tun_softc_lock); 136 137 return (tp); 138 } 139 140 /* 141 * Find zombie driver instance by unit number. 142 * Call at splnet(). 143 * Remove tp from list and return it unlocked (if found). 144 */ 145 static struct tun_softc * 146 tun_find_zunit(int unit) 147 { 148 struct tun_softc *tp; 149 150 simple_lock(&tun_softc_lock); 151 LIST_FOREACH(tp, &tunz_softc_list, tun_list) 152 if (unit == tp->tun_unit) 153 break; 154 if (tp) 155 LIST_REMOVE(tp, tun_list); 156 simple_unlock(&tun_softc_lock); 157 #ifdef DIAGNOSTIC 158 if (tp != NULL && (tp->tun_flags & (TUN_INITED|TUN_OPEN)) != TUN_OPEN) 159 printf("tun%d: inconsistent flags: %x\n", unit, tp->tun_flags); 160 #endif 161 162 return (tp); 163 } 164 165 static int 166 tun_clone_create(struct if_clone *ifc, int unit) 167 { 168 struct tun_softc *tp; 169 170 if ((tp = tun_find_zunit(unit)) == NULL) { 171 /* Allocate a new instance */ 172 tp = malloc(sizeof(struct tun_softc), M_DEVBUF, M_WAITOK); 173 (void)memset(tp, 0, sizeof(struct tun_softc)); 174 175 tp->tun_unit = unit; 176 simple_lock_init(&tp->tun_lock); 177 } else { 178 /* Revive tunnel instance; clear ifp part */ 179 (void)memset(&tp->tun_if, 0, sizeof(struct ifnet)); 180 } 181 182 (void)snprintf(tp->tun_if.if_xname, sizeof(tp->tun_if.if_xname), 183 "%s%d", ifc->ifc_name, unit); 184 tunattach0(tp); 185 tp->tun_flags |= TUN_INITED; 186 187 simple_lock(&tun_softc_lock); 188 LIST_INSERT_HEAD(&tun_softc_list, tp, tun_list); 189 simple_unlock(&tun_softc_lock); 190 191 return (0); 192 } 193 194 static void 195 tunattach0(struct tun_softc *tp) 196 { 197 struct ifnet *ifp; 198 199 ifp = &tp->tun_if; 200 ifp->if_softc = tp; 201 ifp->if_mtu = TUNMTU; 202 ifp->if_ioctl = tun_ioctl; 203 ifp->if_output = tun_output; 204 #ifdef ALTQ 205 ifp->if_start = tunstart; 206 #endif 207 ifp->if_flags = IFF_POINTOPOINT; 208 ifp->if_type = IFT_TUNNEL; 209 ifp->if_snd.ifq_maxlen = ifqmaxlen; 210 ifp->if_collisions = 0; 211 ifp->if_ierrors = 0; 212 ifp->if_oerrors = 0; 213 ifp->if_ipackets = 0; 214 ifp->if_opackets = 0; 215 ifp->if_ibytes = 0; 216 ifp->if_obytes = 0; 217 ifp->if_dlt = DLT_NULL; 218 IFQ_SET_READY(&ifp->if_snd); 219 if_attach(ifp); 220 if_alloc_sadl(ifp); 221 #if NBPFILTER > 0 222 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 223 #endif 224 } 225 226 static int 227 tun_clone_destroy(struct ifnet *ifp) 228 { 229 struct tun_softc *tp = (void *)ifp; 230 int s, zombie = 0; 231 232 s = splnet(); 233 simple_lock(&tun_softc_lock); 234 simple_lock(&tp->tun_lock); 235 LIST_REMOVE(tp, tun_list); 236 if (tp->tun_flags & TUN_OPEN) { 237 /* Hang on to storage until last close */ 238 zombie = 1; 239 tp->tun_flags &= ~TUN_INITED; 240 LIST_INSERT_HEAD(&tunz_softc_list, tp, tun_list); 241 } 242 simple_unlock(&tun_softc_lock); 243 244 IF_PURGE(&ifp->if_snd); 245 ifp->if_flags &= ~IFF_RUNNING; 246 247 if (tp->tun_flags & TUN_RWAIT) { 248 tp->tun_flags &= ~TUN_RWAIT; 249 wakeup((caddr_t)tp); 250 } 251 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 252 fownsignal(tp->tun_pgid, SIGIO, POLL_HUP, 0, NULL); 253 254 selwakeup(&tp->tun_rsel); 255 256 simple_unlock(&tp->tun_lock); 257 splx(s); 258 259 #if NBPFILTER > 0 260 bpfdetach(ifp); 261 #endif 262 if_detach(ifp); 263 264 if (!zombie) 265 free(tp, M_DEVBUF); 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 proc *p = l->l_proc; 278 struct ifnet *ifp; 279 struct tun_softc *tp; 280 int s, error; 281 282 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0) 283 return (error); 284 285 s = splnet(); 286 tp = tun_find_unit(dev); 287 288 if (tp == NULL) { 289 (void)tun_clone_create(&tun_cloner, minor(dev)); 290 tp = tun_find_unit(dev); 291 if (tp == NULL) { 292 error = ENXIO; 293 goto out_nolock; 294 } 295 } 296 297 if (tp->tun_flags & TUN_OPEN) { 298 error = EBUSY; 299 goto out; 300 } 301 302 ifp = &tp->tun_if; 303 tp->tun_flags |= TUN_OPEN; 304 TUNDEBUG("%s: open\n", ifp->if_xname); 305 out: 306 simple_unlock(&tp->tun_lock); 307 out_nolock: 308 splx(s); 309 return (error); 310 } 311 312 /* 313 * tunclose - close the device - mark i/f down & delete 314 * routing info 315 */ 316 int 317 tunclose(dev_t dev, int flag, int mode, 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 free(tp, M_DEVBUF); 327 goto out_nolock; 328 } 329 330 if ((tp = tun_find_unit(dev)) == NULL) 331 goto out_nolock; 332 333 ifp = &tp->tun_if; 334 335 tp->tun_flags &= ~TUN_OPEN; 336 337 /* 338 * junk all pending output 339 */ 340 IFQ_PURGE(&ifp->if_snd); 341 342 if (ifp->if_flags & IFF_UP) { 343 if_down(ifp); 344 if (ifp->if_flags & IFF_RUNNING) { 345 /* find internet addresses and delete routes */ 346 struct ifaddr *ifa; 347 IFADDR_FOREACH(ifa, ifp) { 348 #ifdef INET 349 if (ifa->ifa_addr->sa_family == AF_INET) { 350 rtinit(ifa, (int)RTM_DELETE, 351 tp->tun_flags & TUN_DSTADDR 352 ? RTF_HOST 353 : 0); 354 } 355 #endif 356 } 357 } 358 } 359 tp->tun_pgid = 0; 360 selnotify(&tp->tun_rsel, 0); 361 362 TUNDEBUG ("%s: closed\n", ifp->if_xname); 363 simple_unlock(&tp->tun_lock); 364 out_nolock: 365 splx(s); 366 return (0); 367 } 368 369 /* 370 * Call at splnet() with tp locked. 371 */ 372 static void 373 tuninit(struct tun_softc *tp) 374 { 375 struct ifnet *ifp = &tp->tun_if; 376 struct ifaddr *ifa; 377 378 TUNDEBUG("%s: tuninit\n", ifp->if_xname); 379 380 ifp->if_flags |= IFF_UP | IFF_RUNNING; 381 382 tp->tun_flags &= ~(TUN_IASET|TUN_DSTADDR); 383 IFADDR_FOREACH(ifa, ifp) { 384 #ifdef INET 385 if (ifa->ifa_addr->sa_family == AF_INET) { 386 struct sockaddr_in *sin; 387 388 sin = satosin(ifa->ifa_addr); 389 if (sin && sin->sin_addr.s_addr) 390 tp->tun_flags |= TUN_IASET; 391 392 if (ifp->if_flags & IFF_POINTOPOINT) { 393 sin = satosin(ifa->ifa_dstaddr); 394 if (sin && sin->sin_addr.s_addr) 395 tp->tun_flags |= TUN_DSTADDR; 396 } 397 } 398 #endif 399 } 400 401 return; 402 } 403 404 /* 405 * Process an ioctl request. 406 */ 407 static int 408 tun_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 409 { 410 int error = 0, s; 411 struct tun_softc *tp = (struct tun_softc *)(ifp->if_softc); 412 413 s = splnet(); 414 simple_lock(&tp->tun_lock); 415 416 switch (cmd) { 417 case SIOCSIFADDR: 418 tuninit(tp); 419 TUNDEBUG("%s: address set\n", ifp->if_xname); 420 break; 421 case SIOCSIFDSTADDR: 422 tuninit(tp); 423 TUNDEBUG("%s: destination address set\n", ifp->if_xname); 424 break; 425 case SIOCSIFBRDADDR: 426 TUNDEBUG("%s: broadcast address set\n", ifp->if_xname); 427 break; 428 case SIOCSIFMTU: { 429 struct ifreq *ifr = (struct ifreq *) data; 430 if (ifr->ifr_mtu > TUNMTU || ifr->ifr_mtu < 576) { 431 error = EINVAL; 432 break; 433 } 434 TUNDEBUG("%s: interface mtu set\n", ifp->if_xname); 435 ifp->if_mtu = ifr->ifr_mtu; 436 break; 437 } 438 case SIOCADDMULTI: 439 case SIOCDELMULTI: { 440 struct ifreq *ifr = (struct ifreq *) data; 441 if (ifr == 0) { 442 error = EAFNOSUPPORT; /* XXX */ 443 break; 444 } 445 switch (ifr->ifr_addr.sa_family) { 446 #ifdef INET 447 case AF_INET: 448 break; 449 #endif 450 default: 451 error = EAFNOSUPPORT; 452 break; 453 } 454 break; 455 } 456 case SIOCSIFFLAGS: 457 break; 458 default: 459 error = EINVAL; 460 } 461 462 simple_unlock(&tp->tun_lock); 463 splx(s); 464 return (error); 465 } 466 467 /* 468 * tun_output - queue packets from higher level ready to put out. 469 */ 470 static int 471 tun_output(struct ifnet *ifp, struct mbuf *m0, struct sockaddr *dst, 472 struct rtentry *rt) 473 { 474 struct tun_softc *tp = ifp->if_softc; 475 int s; 476 int error; 477 #ifdef INET 478 int mlen; 479 #endif 480 ALTQ_DECL(struct altq_pktattr pktattr;) 481 482 s = splnet(); 483 simple_lock(&tp->tun_lock); 484 TUNDEBUG ("%s: tun_output\n", ifp->if_xname); 485 486 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 487 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, 488 tp->tun_flags); 489 m_freem (m0); 490 error = EHOSTDOWN; 491 goto out; 492 } 493 494 /* 495 * if the queueing discipline needs packet classification, 496 * do it before prepending link headers. 497 */ 498 IFQ_CLASSIFY(&ifp->if_snd, m0, dst->sa_family, &pktattr); 499 500 #if NBPFILTER > 0 501 if (ifp->if_bpf) 502 bpf_mtap_af(ifp->if_bpf, dst->sa_family, m0); 503 #endif 504 505 switch(dst->sa_family) { 506 #ifdef INET 507 case AF_INET: 508 if (tp->tun_flags & TUN_PREPADDR) { 509 /* Simple link-layer header */ 510 M_PREPEND(m0, dst->sa_len, M_DONTWAIT); 511 if (m0 == NULL) { 512 IF_DROP(&ifp->if_snd); 513 error = ENOBUFS; 514 goto out; 515 } 516 bcopy(dst, mtod(m0, char *), dst->sa_len); 517 } 518 /* FALLTHROUGH */ 519 case AF_UNSPEC: 520 IFQ_ENQUEUE(&ifp->if_snd, m0, &pktattr, error); 521 if (error) { 522 ifp->if_collisions++; 523 error = EAFNOSUPPORT; 524 goto out; 525 } 526 mlen = m0->m_pkthdr.len; 527 ifp->if_opackets++; 528 ifp->if_obytes += mlen; 529 break; 530 #endif 531 default: 532 m_freem(m0); 533 error = EAFNOSUPPORT; 534 goto out; 535 } 536 537 if (tp->tun_flags & TUN_RWAIT) { 538 tp->tun_flags &= ~TUN_RWAIT; 539 wakeup((caddr_t)tp); 540 } 541 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 542 fownsignal(tp->tun_pgid, SIGIO, POLL_IN, POLLIN|POLLRDNORM, 543 NULL); 544 545 selnotify(&tp->tun_rsel, 0); 546 out: 547 simple_unlock(&tp->tun_lock); 548 splx(s); 549 return (0); 550 } 551 552 /* 553 * the cdevsw interface is now pretty minimal. 554 */ 555 int 556 tunioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct lwp *l) 557 { 558 struct tun_softc *tp; 559 int s, error = 0; 560 561 s = splnet(); 562 tp = tun_find_unit(dev); 563 564 /* interface was "destroyed" already */ 565 if (tp == NULL) { 566 error = ENXIO; 567 goto out_nolock; 568 } 569 570 switch (cmd) { 571 case TUNSDEBUG: 572 tundebug = *(int *)data; 573 break; 574 575 case TUNGDEBUG: 576 *(int *)data = tundebug; 577 break; 578 579 case TUNSIFMODE: 580 switch (*(int *)data & (IFF_POINTOPOINT|IFF_BROADCAST)) { 581 case IFF_POINTOPOINT: 582 case IFF_BROADCAST: 583 if (tp->tun_if.if_flags & IFF_UP) { 584 error = EBUSY; 585 goto out; 586 } 587 tp->tun_if.if_flags &= 588 ~(IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST); 589 tp->tun_if.if_flags |= *(int *)data; 590 break; 591 default: 592 error = EINVAL; 593 goto out; 594 } 595 break; 596 597 case TUNSLMODE: 598 if (*(int *)data) 599 tp->tun_flags |= TUN_PREPADDR; 600 else 601 tp->tun_flags &= ~TUN_PREPADDR; 602 break; 603 604 case FIONBIO: 605 if (*(int *)data) 606 tp->tun_flags |= TUN_NBIO; 607 else 608 tp->tun_flags &= ~TUN_NBIO; 609 break; 610 611 case FIOASYNC: 612 if (*(int *)data) 613 tp->tun_flags |= TUN_ASYNC; 614 else 615 tp->tun_flags &= ~TUN_ASYNC; 616 break; 617 618 case FIONREAD: 619 if (tp->tun_if.if_snd.ifq_head) 620 *(int *)data = tp->tun_if.if_snd.ifq_head->m_pkthdr.len; 621 else 622 *(int *)data = 0; 623 break; 624 625 case TIOCSPGRP: 626 case FIOSETOWN: 627 error = fsetown(l->l_proc, &tp->tun_pgid, cmd, data); 628 break; 629 630 case TIOCGPGRP: 631 case FIOGETOWN: 632 error = fgetown(l->l_proc, tp->tun_pgid, cmd, data); 633 break; 634 635 default: 636 error = ENOTTY; 637 } 638 639 out: 640 simple_unlock(&tp->tun_lock); 641 out_nolock: 642 splx(s); 643 return (error); 644 } 645 646 /* 647 * The cdevsw read interface - reads a packet at a time, or at 648 * least as much of a packet as can be read. 649 */ 650 int 651 tunread(dev_t dev, struct uio *uio, int ioflag) 652 { 653 struct tun_softc *tp; 654 struct ifnet *ifp; 655 struct mbuf *m, *m0; 656 int error = 0, len, s, index; 657 658 s = splnet(); 659 tp = tun_find_unit(dev); 660 661 /* interface was "destroyed" already */ 662 if (tp == NULL) { 663 error = ENXIO; 664 goto out_nolock; 665 } 666 667 index = tp->tun_if.if_index; 668 ifp = &tp->tun_if; 669 670 TUNDEBUG ("%s: read\n", ifp->if_xname); 671 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 672 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, tp->tun_flags); 673 error = EHOSTDOWN; 674 goto out; 675 } 676 677 tp->tun_flags &= ~TUN_RWAIT; 678 679 do { 680 IFQ_DEQUEUE(&ifp->if_snd, m0); 681 if (m0 == 0) { 682 if (tp->tun_flags & TUN_NBIO) { 683 error = EWOULDBLOCK; 684 goto out; 685 } 686 tp->tun_flags |= TUN_RWAIT; 687 if (ltsleep((caddr_t)tp, PZERO|PCATCH|PNORELOCK, 688 "tunread", 0, &tp->tun_lock) != 0) { 689 error = EINTR; 690 goto out_nolock; 691 } else { 692 /* 693 * Maybe the interface was destroyed while 694 * we were sleeping, so let's ensure that 695 * we're looking at the same (valid) tun 696 * interface before looping. 697 */ 698 tp = tun_find_unit(dev); 699 if (tp == NULL) { 700 error = ENXIO; 701 goto out_nolock; 702 } 703 if (tp->tun_if.if_index != index) { 704 error = ENXIO; 705 goto out; 706 } 707 } 708 } 709 } while (m0 == 0); 710 711 simple_unlock(&tp->tun_lock); 712 splx(s); 713 714 /* Copy the mbuf chain */ 715 while (m0 && uio->uio_resid > 0 && error == 0) { 716 len = min(uio->uio_resid, m0->m_len); 717 if (len != 0) 718 error = uiomove(mtod(m0, caddr_t), len, uio); 719 MFREE(m0, m); 720 m0 = m; 721 } 722 723 if (m0) { 724 TUNDEBUG("Dropping mbuf\n"); 725 m_freem(m0); 726 } 727 if (error) 728 ifp->if_ierrors++; 729 730 return (error); 731 732 out: 733 simple_unlock(&tp->tun_lock); 734 out_nolock: 735 splx(s); 736 return (error); 737 } 738 739 /* 740 * the cdevsw write interface - an atomic write is a packet - or else! 741 */ 742 int 743 tunwrite(dev_t dev, struct uio *uio, int ioflag) 744 { 745 struct tun_softc *tp; 746 struct ifnet *ifp; 747 struct mbuf *top, **mp, *m; 748 struct ifqueue *ifq; 749 struct sockaddr dst; 750 int isr, error = 0, s, tlen, mlen; 751 752 s = splnet(); 753 tp = tun_find_unit(dev); 754 755 /* interface was "destroyed" already */ 756 if (tp == NULL) { 757 error = ENXIO; 758 goto out_nolock; 759 } 760 761 /* Unlock until we've got the data */ 762 simple_unlock(&tp->tun_lock); 763 splx(s); 764 765 ifp = &tp->tun_if; 766 767 TUNDEBUG("%s: tunwrite\n", ifp->if_xname); 768 769 if (tp->tun_flags & TUN_PREPADDR) { 770 if (uio->uio_resid < sizeof(dst)) { 771 error = EIO; 772 goto out0; 773 } 774 error = uiomove((caddr_t)&dst, sizeof(dst), uio); 775 if (dst.sa_len > sizeof(dst)) { 776 /* Duh.. */ 777 char discard; 778 int n = dst.sa_len - sizeof(dst); 779 while (n--) 780 if ((error = uiomove(&discard, 1, uio)) != 0) { 781 goto out0; 782 } 783 } 784 } else { 785 #ifdef INET 786 dst.sa_family = AF_INET; 787 #endif 788 } 789 790 if (uio->uio_resid > TUNMTU) { 791 TUNDEBUG("%s: len=%lu!\n", ifp->if_xname, 792 (unsigned long)uio->uio_resid); 793 error = EIO; 794 goto out0; 795 } 796 797 switch (dst.sa_family) { 798 #ifdef INET 799 case AF_INET: 800 ifq = &ipintrq; 801 isr = NETISR_IP; 802 break; 803 #endif 804 default: 805 error = EAFNOSUPPORT; 806 goto out0; 807 } 808 809 tlen = uio->uio_resid; 810 811 /* get a header mbuf */ 812 MGETHDR(m, M_DONTWAIT, MT_DATA); 813 if (m == NULL) { 814 error = ENOBUFS; 815 goto out0; 816 } 817 mlen = MHLEN; 818 819 top = NULL; 820 mp = ⊤ 821 while (error == 0 && uio->uio_resid > 0) { 822 m->m_len = min(mlen, uio->uio_resid); 823 error = uiomove(mtod(m, caddr_t), m->m_len, uio); 824 *mp = m; 825 mp = &m->m_next; 826 if (error == 0 && uio->uio_resid > 0) { 827 MGET(m, M_DONTWAIT, MT_DATA); 828 if (m == NULL) { 829 error = ENOBUFS; 830 break; 831 } 832 mlen = MLEN; 833 } 834 } 835 if (error) { 836 if (top != NULL) 837 m_freem (top); 838 ifp->if_ierrors++; 839 goto out0; 840 } 841 842 top->m_pkthdr.len = tlen; 843 top->m_pkthdr.rcvif = ifp; 844 845 #if NBPFILTER > 0 846 if (ifp->if_bpf) 847 bpf_mtap_af(ifp->if_bpf, AF_INET, top); 848 #endif 849 850 s = splnet(); 851 simple_lock(&tp->tun_lock); 852 if ((tp->tun_flags & TUN_INITED) == 0) { 853 /* Interface was destroyed */ 854 error = ENXIO; 855 goto out; 856 } 857 if (IF_QFULL(ifq)) { 858 IF_DROP(ifq); 859 ifp->if_collisions++; 860 m_freem(top); 861 error = ENOBUFS; 862 goto out; 863 } 864 865 IF_ENQUEUE(ifq, top); 866 ifp->if_ipackets++; 867 ifp->if_ibytes += tlen; 868 schednetisr(isr); 869 out: 870 simple_unlock(&tp->tun_lock); 871 out_nolock: 872 splx(s); 873 out0: 874 return (error); 875 } 876 877 #ifdef ALTQ 878 /* 879 * Start packet transmission on the interface. 880 * when the interface queue is rate-limited by ALTQ or TBR, 881 * if_start is needed to drain packets from the queue in order 882 * to notify readers when outgoing packets become ready. 883 * 884 * Should be called at splnet. 885 */ 886 static void 887 tunstart(struct ifnet *ifp) 888 { 889 struct tun_softc *tp = ifp->if_softc; 890 891 if (!ALTQ_IS_ENABLED(&ifp->if_snd) && !TBR_IS_ENABLED(&ifp->if_snd)) 892 return; 893 894 simple_lock(&tp->tun_lock); 895 if (!IF_IS_EMPTY(&ifp->if_snd)) { 896 if (tp->tun_flags & TUN_RWAIT) { 897 tp->tun_flags &= ~TUN_RWAIT; 898 wakeup((caddr_t)tp); 899 } 900 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 901 fownsignal(tp->tun_pgid, SIGIO, POLL_OUT, 902 POLLOUT|POLLWRNORM, NULL); 903 904 selwakeup(&tp->tun_rsel); 905 } 906 simple_unlock(&tp->tun_lock); 907 } 908 #endif /* ALTQ */ 909 /* 910 * tunpoll - the poll interface, this is only useful on reads 911 * really. The write detect always returns true, write never blocks 912 * anyway, it either accepts the packet or drops it. 913 */ 914 int 915 tunpoll(dev_t dev, int events, struct lwp *l) 916 { 917 struct tun_softc *tp; 918 struct ifnet *ifp; 919 int s, revents = 0; 920 921 s = splnet(); 922 tp = tun_find_unit(dev); 923 924 /* interface was "destroyed" already */ 925 if (tp == NULL) 926 goto out_nolock; 927 928 ifp = &tp->tun_if; 929 930 TUNDEBUG("%s: tunpoll\n", ifp->if_xname); 931 932 if (events & (POLLIN | POLLRDNORM)) { 933 if (!IFQ_IS_EMPTY(&ifp->if_snd)) { 934 TUNDEBUG("%s: tunpoll q=%d\n", ifp->if_xname, 935 ifp->if_snd.ifq_len); 936 revents |= events & (POLLIN | POLLRDNORM); 937 } else { 938 TUNDEBUG("%s: tunpoll waiting\n", ifp->if_xname); 939 selrecord(l, &tp->tun_rsel); 940 } 941 } 942 943 if (events & (POLLOUT | POLLWRNORM)) 944 revents |= events & (POLLOUT | POLLWRNORM); 945 946 simple_unlock(&tp->tun_lock); 947 out_nolock: 948 splx(s); 949 return (revents); 950 } 951 952 static void 953 filt_tunrdetach(struct knote *kn) 954 { 955 struct tun_softc *tp = kn->kn_hook; 956 int s; 957 958 s = splnet(); 959 SLIST_REMOVE(&tp->tun_rsel.sel_klist, kn, knote, kn_selnext); 960 splx(s); 961 } 962 963 static int 964 filt_tunread(struct knote *kn, long hint) 965 { 966 struct tun_softc *tp = kn->kn_hook; 967 struct ifnet *ifp = &tp->tun_if; 968 struct mbuf *m; 969 int s; 970 971 s = splnet(); 972 IF_POLL(&ifp->if_snd, m); 973 if (m == NULL) { 974 splx(s); 975 return (0); 976 } 977 978 for (kn->kn_data = 0; m != NULL; m = m->m_next) 979 kn->kn_data += m->m_len; 980 981 splx(s); 982 return (1); 983 } 984 985 static const struct filterops tunread_filtops = 986 { 1, NULL, filt_tunrdetach, filt_tunread }; 987 988 static const struct filterops tun_seltrue_filtops = 989 { 1, NULL, filt_tunrdetach, filt_seltrue }; 990 991 int 992 tunkqfilter(dev_t dev, struct knote *kn) 993 { 994 struct tun_softc *tp; 995 struct klist *klist; 996 int rv = 0, s; 997 998 s = splnet(); 999 tp = tun_find_unit(dev); 1000 if (tp == NULL) 1001 goto out_nolock; 1002 1003 switch (kn->kn_filter) { 1004 case EVFILT_READ: 1005 klist = &tp->tun_rsel.sel_klist; 1006 kn->kn_fop = &tunread_filtops; 1007 break; 1008 1009 case EVFILT_WRITE: 1010 klist = &tp->tun_rsel.sel_klist; 1011 kn->kn_fop = &tun_seltrue_filtops; 1012 break; 1013 1014 default: 1015 rv = 1; 1016 goto out; 1017 } 1018 1019 kn->kn_hook = tp; 1020 1021 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 1022 1023 out: 1024 simple_unlock(&tp->tun_lock); 1025 out_nolock: 1026 splx(s); 1027 return (rv); 1028 } 1029