1 /* $NetBSD: if_tun.c,v 1.72 2004/08/19 20:58:24 christos 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 1.72 2004/08/19 20:58:24 christos Exp $"); 19 20 #include "tun.h" 21 22 #include "opt_inet.h" 23 #include "opt_ns.h" 24 25 #include <sys/param.h> 26 #include <sys/proc.h> 27 #include <sys/systm.h> 28 #include <sys/mbuf.h> 29 #include <sys/buf.h> 30 #include <sys/protosw.h> 31 #include <sys/socket.h> 32 #include <sys/ioctl.h> 33 #include <sys/errno.h> 34 #include <sys/syslog.h> 35 #include <sys/select.h> 36 #include <sys/poll.h> 37 #include <sys/file.h> 38 #include <sys/signalvar.h> 39 #include <sys/conf.h> 40 41 #include <machine/cpu.h> 42 43 #include <net/if.h> 44 #include <net/if_types.h> 45 #include <net/netisr.h> 46 #include <net/route.h> 47 48 49 #ifdef INET 50 #include <netinet/in.h> 51 #include <netinet/in_systm.h> 52 #include <netinet/in_var.h> 53 #include <netinet/ip.h> 54 #include <netinet/if_inarp.h> 55 #endif 56 57 #ifdef NS 58 #include <netns/ns.h> 59 #include <netns/ns_if.h> 60 #endif 61 62 #include "bpfilter.h" 63 #if NBPFILTER > 0 64 #include <sys/time.h> 65 #include <net/bpf.h> 66 #endif 67 68 #include <net/if_tun.h> 69 70 #define TUNDEBUG if (tundebug) printf 71 int tundebug = 0; 72 73 extern int ifqmaxlen; 74 void tunattach __P((int)); 75 LIST_HEAD(, tun_softc) tun_softc_list; 76 LIST_HEAD(, tun_softc) tunz_softc_list; 77 static struct simplelock tun_softc_lock; 78 79 int tun_ioctl __P((struct ifnet *, u_long, caddr_t)); 80 int tun_output __P((struct ifnet *, struct mbuf *, struct sockaddr *, 81 struct rtentry *rt)); 82 int tun_clone_create __P((struct if_clone *, int)); 83 void tun_clone_destroy __P((struct ifnet *)); 84 85 struct if_clone tun_cloner = 86 IF_CLONE_INITIALIZER("tun", tun_clone_create, tun_clone_destroy); 87 88 static void tunattach0 __P((struct tun_softc *)); 89 static void tuninit __P((struct tun_softc *)); 90 #ifdef ALTQ 91 static void tunstart __P((struct ifnet *)); 92 #endif 93 static struct tun_softc *tun_find_unit __P((dev_t)); 94 static struct tun_softc *tun_find_zunit __P((int)); 95 96 dev_type_open(tunopen); 97 dev_type_close(tunclose); 98 dev_type_read(tunread); 99 dev_type_write(tunwrite); 100 dev_type_ioctl(tunioctl); 101 dev_type_poll(tunpoll); 102 dev_type_kqfilter(tunkqfilter); 103 104 const struct cdevsw tun_cdevsw = { 105 tunopen, tunclose, tunread, tunwrite, tunioctl, 106 nostop, notty, tunpoll, nommap, tunkqfilter, 107 }; 108 109 void 110 tunattach(unused) 111 int unused; 112 { 113 114 simple_lock_init(&tun_softc_lock); 115 LIST_INIT(&tun_softc_list); 116 LIST_INIT(&tunz_softc_list); 117 if_clone_attach(&tun_cloner); 118 } 119 120 /* 121 * Find driver instance from dev_t. 122 * Call at splnet(). 123 * Returns with tp locked (if found). 124 */ 125 static struct tun_softc * 126 tun_find_unit(dev) 127 dev_t dev; 128 { 129 struct tun_softc *tp; 130 int unit = minor(dev); 131 132 simple_lock(&tun_softc_lock); 133 LIST_FOREACH(tp, &tun_softc_list, tun_list) 134 if (unit == tp->tun_unit) 135 break; 136 if (tp) 137 simple_lock(&tp->tun_lock); 138 simple_unlock(&tun_softc_lock); 139 140 return (tp); 141 } 142 143 /* 144 * Find zombie driver instance by unit number. 145 * Call at splnet(). 146 * Remove tp from list and return it unlocked (if found). 147 */ 148 static struct tun_softc * 149 tun_find_zunit(unit) 150 int unit; 151 { 152 struct tun_softc *tp; 153 154 simple_lock(&tun_softc_lock); 155 LIST_FOREACH(tp, &tunz_softc_list, tun_list) 156 if (unit == tp->tun_unit) 157 break; 158 if (tp) 159 LIST_REMOVE(tp, tun_list); 160 simple_unlock(&tun_softc_lock); 161 #ifdef DIAGNOSTIC 162 if (tp != NULL && (tp->tun_flags & (TUN_INITED|TUN_OPEN)) != TUN_OPEN) 163 printf("tun%d: inconsistent flags: %x\n", unit, tp->tun_flags); 164 #endif 165 166 return (tp); 167 } 168 169 int 170 tun_clone_create(ifc, unit) 171 struct if_clone *ifc; 172 int unit; 173 { 174 struct tun_softc *tp; 175 176 if ((tp = tun_find_zunit(unit)) == NULL) { 177 /* Allocate a new instance */ 178 tp = malloc(sizeof(struct tun_softc), M_DEVBUF, M_WAITOK); 179 (void)memset(tp, 0, sizeof(struct tun_softc)); 180 181 tp->tun_unit = unit; 182 simple_lock_init(&tp->tun_lock); 183 } else { 184 /* Revive tunnel instance; clear ifp part */ 185 (void)memset(&tp->tun_if, 0, sizeof(struct ifnet)); 186 } 187 188 (void)snprintf(tp->tun_if.if_xname, sizeof(tp->tun_if.if_xname), 189 "%s%d", ifc->ifc_name, unit); 190 tunattach0(tp); 191 tp->tun_flags |= TUN_INITED; 192 193 simple_lock(&tun_softc_lock); 194 LIST_INSERT_HEAD(&tun_softc_list, tp, tun_list); 195 simple_unlock(&tun_softc_lock); 196 197 return (0); 198 } 199 200 void 201 tunattach0(tp) 202 struct tun_softc *tp; 203 { 204 struct ifnet *ifp; 205 206 ifp = &tp->tun_if; 207 ifp->if_softc = tp; 208 ifp->if_mtu = TUNMTU; 209 ifp->if_ioctl = tun_ioctl; 210 ifp->if_output = tun_output; 211 #ifdef ALTQ 212 ifp->if_start = tunstart; 213 #endif 214 ifp->if_flags = IFF_POINTOPOINT; 215 ifp->if_type = IFT_TUNNEL; 216 ifp->if_snd.ifq_maxlen = ifqmaxlen; 217 ifp->if_collisions = 0; 218 ifp->if_ierrors = 0; 219 ifp->if_oerrors = 0; 220 ifp->if_ipackets = 0; 221 ifp->if_opackets = 0; 222 ifp->if_ibytes = 0; 223 ifp->if_obytes = 0; 224 ifp->if_dlt = DLT_NULL; 225 IFQ_SET_READY(&ifp->if_snd); 226 if_attach(ifp); 227 if_alloc_sadl(ifp); 228 #if NBPFILTER > 0 229 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 230 #endif 231 } 232 233 void 234 tun_clone_destroy(ifp) 235 struct ifnet *ifp; 236 { 237 struct tun_softc *tp = (void *)ifp; 238 int s, zombie = 0; 239 240 s = splnet(); 241 simple_lock(&tun_softc_lock); 242 simple_lock(&tp->tun_lock); 243 LIST_REMOVE(tp, tun_list); 244 if (tp->tun_flags & TUN_OPEN) { 245 /* Hang on to storage until last close */ 246 zombie = 1; 247 tp->tun_flags &= ~TUN_INITED; 248 LIST_INSERT_HEAD(&tunz_softc_list, tp, tun_list); 249 } 250 simple_unlock(&tun_softc_lock); 251 252 IF_PURGE(&ifp->if_snd); 253 ifp->if_flags &= ~IFF_RUNNING; 254 255 if (tp->tun_flags & TUN_RWAIT) { 256 tp->tun_flags &= ~TUN_RWAIT; 257 wakeup((caddr_t)tp); 258 } 259 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 260 fownsignal(tp->tun_pgid, SIGIO, POLL_HUP, 0, NULL); 261 262 selwakeup(&tp->tun_rsel); 263 264 simple_unlock(&tp->tun_lock); 265 splx(s); 266 267 #if NBPFILTER > 0 268 bpfdetach(ifp); 269 #endif 270 if_detach(ifp); 271 272 if (!zombie) 273 free(tp, M_DEVBUF); 274 } 275 276 /* 277 * tunnel open - must be superuser & the device must be 278 * configured in 279 */ 280 int 281 tunopen(dev, flag, mode, p) 282 dev_t dev; 283 int flag, mode; 284 struct proc *p; 285 { 286 struct ifnet *ifp; 287 struct tun_softc *tp; 288 int s, error; 289 290 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0) 291 return (error); 292 293 if (NTUN < 1) 294 return (ENXIO); 295 296 s = splnet(); 297 tp = tun_find_unit(dev); 298 299 if (tp == NULL) { 300 (void)tun_clone_create(&tun_cloner, minor(dev)); 301 tp = tun_find_unit(dev); 302 if (tp == NULL) { 303 error = ENXIO; 304 goto out_nolock; 305 } 306 } 307 308 if (tp->tun_flags & TUN_OPEN) { 309 error = EBUSY; 310 goto out; 311 } 312 313 ifp = &tp->tun_if; 314 tp->tun_flags |= TUN_OPEN; 315 TUNDEBUG("%s: open\n", ifp->if_xname); 316 out: 317 simple_unlock(&tp->tun_lock); 318 out_nolock: 319 splx(s); 320 return (error); 321 } 322 323 /* 324 * tunclose - close the device - mark i/f down & delete 325 * routing info 326 */ 327 int 328 tunclose(dev, flag, mode, p) 329 dev_t dev; 330 int flag; 331 int mode; 332 struct proc *p; 333 { 334 int s; 335 struct tun_softc *tp; 336 struct ifnet *ifp; 337 338 s = splnet(); 339 if ((tp = tun_find_zunit(minor(dev))) != NULL) { 340 /* interface was "destroyed" before the close */ 341 free(tp, M_DEVBUF); 342 goto out_nolock; 343 } 344 345 if ((tp = tun_find_unit(dev)) == NULL) 346 goto out_nolock; 347 348 ifp = &tp->tun_if; 349 350 tp->tun_flags &= ~TUN_OPEN; 351 352 /* 353 * junk all pending output 354 */ 355 IFQ_PURGE(&ifp->if_snd); 356 357 if (ifp->if_flags & IFF_UP) { 358 if_down(ifp); 359 if (ifp->if_flags & IFF_RUNNING) { 360 /* find internet addresses and delete routes */ 361 struct ifaddr *ifa; 362 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 363 #ifdef INET 364 if (ifa->ifa_addr->sa_family == AF_INET) { 365 rtinit(ifa, (int)RTM_DELETE, 366 tp->tun_flags & TUN_DSTADDR 367 ? RTF_HOST 368 : 0); 369 } 370 #endif 371 } 372 } 373 } 374 tp->tun_pgid = 0; 375 selnotify(&tp->tun_rsel, 0); 376 377 TUNDEBUG ("%s: closed\n", ifp->if_xname); 378 simple_unlock(&tp->tun_lock); 379 out_nolock: 380 splx(s); 381 return (0); 382 } 383 384 /* 385 * Call at splnet() with tp locked. 386 */ 387 static void 388 tuninit(tp) 389 struct tun_softc *tp; 390 { 391 struct ifnet *ifp = &tp->tun_if; 392 struct ifaddr *ifa; 393 394 TUNDEBUG("%s: tuninit\n", ifp->if_xname); 395 396 ifp->if_flags |= IFF_UP | IFF_RUNNING; 397 398 tp->tun_flags &= ~(TUN_IASET|TUN_DSTADDR); 399 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 400 #ifdef INET 401 if (ifa->ifa_addr->sa_family == AF_INET) { 402 struct sockaddr_in *sin; 403 404 sin = satosin(ifa->ifa_addr); 405 if (sin && sin->sin_addr.s_addr) 406 tp->tun_flags |= TUN_IASET; 407 408 if (ifp->if_flags & IFF_POINTOPOINT) { 409 sin = satosin(ifa->ifa_dstaddr); 410 if (sin && sin->sin_addr.s_addr) 411 tp->tun_flags |= TUN_DSTADDR; 412 } 413 } 414 #endif 415 } 416 417 return; 418 } 419 420 /* 421 * Process an ioctl request. 422 */ 423 int 424 tun_ioctl(ifp, cmd, data) 425 struct ifnet *ifp; 426 u_long cmd; 427 caddr_t data; 428 { 429 int error = 0, s; 430 struct tun_softc *tp = (struct tun_softc *)(ifp->if_softc); 431 432 s = splnet(); 433 simple_lock(&tp->tun_lock); 434 435 switch (cmd) { 436 case SIOCSIFADDR: 437 tuninit(tp); 438 TUNDEBUG("%s: address set\n", ifp->if_xname); 439 break; 440 case SIOCSIFDSTADDR: 441 tuninit(tp); 442 TUNDEBUG("%s: destination address set\n", ifp->if_xname); 443 break; 444 case SIOCSIFBRDADDR: 445 TUNDEBUG("%s: broadcast address set\n", ifp->if_xname); 446 break; 447 case SIOCSIFMTU: { 448 struct ifreq *ifr = (struct ifreq *) data; 449 if (ifr->ifr_mtu > TUNMTU || ifr->ifr_mtu < 576) { 450 error = EINVAL; 451 break; 452 } 453 TUNDEBUG("%s: interface mtu set\n", ifp->if_xname); 454 ifp->if_mtu = ifr->ifr_mtu; 455 break; 456 } 457 case SIOCADDMULTI: 458 case SIOCDELMULTI: { 459 struct ifreq *ifr = (struct ifreq *) data; 460 if (ifr == 0) { 461 error = EAFNOSUPPORT; /* XXX */ 462 break; 463 } 464 switch (ifr->ifr_addr.sa_family) { 465 #ifdef INET 466 case AF_INET: 467 break; 468 #endif 469 default: 470 error = EAFNOSUPPORT; 471 break; 472 } 473 break; 474 } 475 case SIOCSIFFLAGS: 476 break; 477 default: 478 error = EINVAL; 479 } 480 481 simple_unlock(&tp->tun_lock); 482 splx(s); 483 return (error); 484 } 485 486 /* 487 * tun_output - queue packets from higher level ready to put out. 488 */ 489 int 490 tun_output(ifp, m0, dst, rt) 491 struct ifnet *ifp; 492 struct mbuf *m0; 493 struct sockaddr *dst; 494 struct rtentry *rt; 495 { 496 struct tun_softc *tp = ifp->if_softc; 497 #ifdef INET 498 int s; 499 int error; 500 #endif 501 int mlen; 502 ALTQ_DECL(struct altq_pktattr pktattr;) 503 504 s = splnet(); 505 simple_lock(&tp->tun_lock); 506 TUNDEBUG ("%s: tun_output\n", ifp->if_xname); 507 508 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 509 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, 510 tp->tun_flags); 511 m_freem (m0); 512 error = EHOSTDOWN; 513 goto out; 514 } 515 516 /* 517 * if the queueing discipline needs packet classification, 518 * do it before prepending link headers. 519 */ 520 IFQ_CLASSIFY(&ifp->if_snd, m0, dst->sa_family, &pktattr); 521 522 #if NBPFILTER > 0 523 if (ifp->if_bpf) 524 bpf_mtap_af(ifp->if_bpf, dst->sa_family, m0); 525 #endif 526 527 switch(dst->sa_family) { 528 #ifdef INET 529 case AF_INET: 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 /* FALLTHROUGH */ 541 case AF_UNSPEC: 542 IFQ_ENQUEUE(&ifp->if_snd, m0, &pktattr, error); 543 if (error) { 544 ifp->if_collisions++; 545 error = EAFNOSUPPORT; 546 goto out; 547 } 548 mlen = m0->m_pkthdr.len; 549 ifp->if_opackets++; 550 ifp->if_obytes += mlen; 551 break; 552 #endif 553 default: 554 m_freem(m0); 555 error = EAFNOSUPPORT; 556 goto out; 557 } 558 559 if (tp->tun_flags & TUN_RWAIT) { 560 tp->tun_flags &= ~TUN_RWAIT; 561 wakeup((caddr_t)tp); 562 } 563 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 564 fownsignal(tp->tun_pgid, SIGIO, POLL_IN, POLLIN|POLLRDNORM, 565 NULL); 566 567 selnotify(&tp->tun_rsel, 0); 568 out: 569 simple_unlock(&tp->tun_lock); 570 splx(s); 571 return (0); 572 } 573 574 /* 575 * the cdevsw interface is now pretty minimal. 576 */ 577 int 578 tunioctl(dev, cmd, data, flag, p) 579 dev_t dev; 580 u_long cmd; 581 caddr_t data; 582 int flag; 583 struct proc *p; 584 { 585 struct tun_softc *tp; 586 int s, error = 0; 587 588 s = splnet(); 589 tp = tun_find_unit(dev); 590 591 /* interface was "destroyed" already */ 592 if (tp == NULL) { 593 error = ENXIO; 594 goto out_nolock; 595 } 596 597 switch (cmd) { 598 case TUNSDEBUG: 599 tundebug = *(int *)data; 600 break; 601 602 case TUNGDEBUG: 603 *(int *)data = tundebug; 604 break; 605 606 case TUNSIFMODE: 607 switch (*(int *)data & (IFF_POINTOPOINT|IFF_BROADCAST)) { 608 case IFF_POINTOPOINT: 609 case IFF_BROADCAST: 610 if (tp->tun_if.if_flags & IFF_UP) { 611 error = EBUSY; 612 goto out; 613 } 614 tp->tun_if.if_flags &= 615 ~(IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST); 616 tp->tun_if.if_flags |= *(int *)data; 617 break; 618 default: 619 error = EINVAL; 620 goto out; 621 } 622 break; 623 624 case TUNSLMODE: 625 if (*(int *)data) 626 tp->tun_flags |= TUN_PREPADDR; 627 else 628 tp->tun_flags &= ~TUN_PREPADDR; 629 break; 630 631 case FIONBIO: 632 if (*(int *)data) 633 tp->tun_flags |= TUN_NBIO; 634 else 635 tp->tun_flags &= ~TUN_NBIO; 636 break; 637 638 case FIOASYNC: 639 if (*(int *)data) 640 tp->tun_flags |= TUN_ASYNC; 641 else 642 tp->tun_flags &= ~TUN_ASYNC; 643 break; 644 645 case FIONREAD: 646 if (tp->tun_if.if_snd.ifq_head) 647 *(int *)data = tp->tun_if.if_snd.ifq_head->m_pkthdr.len; 648 else 649 *(int *)data = 0; 650 break; 651 652 case TIOCSPGRP: 653 case FIOSETOWN: 654 error = fsetown(p, &tp->tun_pgid, cmd, data); 655 break; 656 657 case TIOCGPGRP: 658 case FIOGETOWN: 659 error = fgetown(p, tp->tun_pgid, cmd, data); 660 break; 661 662 default: 663 error = ENOTTY; 664 } 665 666 out: 667 simple_unlock(&tp->tun_lock); 668 out_nolock: 669 splx(s); 670 return (error); 671 } 672 673 /* 674 * The cdevsw read interface - reads a packet at a time, or at 675 * least as much of a packet as can be read. 676 */ 677 int 678 tunread(dev, uio, ioflag) 679 dev_t dev; 680 struct uio *uio; 681 int ioflag; 682 { 683 struct tun_softc *tp; 684 struct ifnet *ifp; 685 struct mbuf *m, *m0; 686 int error = 0, len, s, index; 687 688 s = splnet(); 689 tp = tun_find_unit(dev); 690 691 /* interface was "destroyed" already */ 692 if (tp == NULL) { 693 error = ENXIO; 694 goto out_nolock; 695 } 696 697 index = tp->tun_if.if_index; 698 ifp = &tp->tun_if; 699 700 TUNDEBUG ("%s: read\n", ifp->if_xname); 701 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 702 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, tp->tun_flags); 703 error = EHOSTDOWN; 704 goto out; 705 } 706 707 tp->tun_flags &= ~TUN_RWAIT; 708 709 do { 710 IFQ_DEQUEUE(&ifp->if_snd, m0); 711 if (m0 == 0) { 712 if (tp->tun_flags & TUN_NBIO) { 713 error = EWOULDBLOCK; 714 goto out; 715 } 716 tp->tun_flags |= TUN_RWAIT; 717 if (ltsleep((caddr_t)tp, PZERO|PCATCH|PNORELOCK, 718 "tunread", 0, &tp->tun_lock) != 0) { 719 error = EINTR; 720 goto out_nolock; 721 } else { 722 /* 723 * Maybe the interface was destroyed while 724 * we were sleeping, so let's ensure that 725 * we're looking at the same (valid) tun 726 * interface before looping. 727 */ 728 tp = tun_find_unit(dev); 729 if (tp == NULL) { 730 error = ENXIO; 731 goto out_nolock; 732 } 733 if (tp->tun_if.if_index != index) { 734 error = ENXIO; 735 goto out; 736 } 737 } 738 } 739 } while (m0 == 0); 740 741 simple_unlock(&tp->tun_lock); 742 splx(s); 743 744 /* Copy the mbuf chain */ 745 while (m0 && uio->uio_resid > 0 && error == 0) { 746 len = min(uio->uio_resid, m0->m_len); 747 if (len != 0) 748 error = uiomove(mtod(m0, caddr_t), len, uio); 749 MFREE(m0, m); 750 m0 = m; 751 } 752 753 if (m0) { 754 TUNDEBUG("Dropping mbuf\n"); 755 m_freem(m0); 756 } 757 if (error) 758 ifp->if_ierrors++; 759 760 return (error); 761 762 out: 763 simple_unlock(&tp->tun_lock); 764 out_nolock: 765 splx(s); 766 return (error); 767 } 768 769 /* 770 * the cdevsw write interface - an atomic write is a packet - or else! 771 */ 772 int 773 tunwrite(dev, uio, ioflag) 774 dev_t dev; 775 struct uio *uio; 776 int ioflag; 777 { 778 struct tun_softc *tp; 779 struct ifnet *ifp; 780 struct mbuf *top, **mp, *m; 781 struct ifqueue *ifq; 782 struct sockaddr dst; 783 int isr, error = 0, s, tlen, mlen; 784 785 s = splnet(); 786 tp = tun_find_unit(dev); 787 788 /* interface was "destroyed" already */ 789 if (tp == NULL) { 790 error = ENXIO; 791 goto out_nolock; 792 } 793 794 /* Unlock until we've got the data */ 795 simple_unlock(&tp->tun_lock); 796 splx(s); 797 798 ifp = &tp->tun_if; 799 800 TUNDEBUG("%s: tunwrite\n", ifp->if_xname); 801 802 if (tp->tun_flags & TUN_PREPADDR) { 803 if (uio->uio_resid < sizeof(dst)) { 804 error = EIO; 805 goto out0; 806 } 807 error = uiomove((caddr_t)&dst, sizeof(dst), uio); 808 if (dst.sa_len > sizeof(dst)) { 809 /* Duh.. */ 810 char discard; 811 int n = dst.sa_len - sizeof(dst); 812 while (n--) 813 if ((error = uiomove(&discard, 1, uio)) != 0) { 814 goto out0; 815 } 816 } 817 } else { 818 #ifdef INET 819 dst.sa_family = AF_INET; 820 #endif 821 } 822 823 if (uio->uio_resid > TUNMTU) { 824 TUNDEBUG("%s: len=%lu!\n", ifp->if_xname, 825 (unsigned long)uio->uio_resid); 826 error = EIO; 827 goto out0; 828 } 829 830 switch (dst.sa_family) { 831 #ifdef INET 832 case AF_INET: 833 ifq = &ipintrq; 834 isr = NETISR_IP; 835 break; 836 #endif 837 default: 838 error = EAFNOSUPPORT; 839 goto out0; 840 } 841 842 tlen = uio->uio_resid; 843 844 /* get a header mbuf */ 845 MGETHDR(m, M_DONTWAIT, MT_DATA); 846 if (m == NULL) { 847 error = ENOBUFS; 848 goto out0; 849 } 850 mlen = MHLEN; 851 852 top = NULL; 853 mp = ⊤ 854 while (error == 0 && uio->uio_resid > 0) { 855 m->m_len = min(mlen, uio->uio_resid); 856 error = uiomove(mtod(m, caddr_t), m->m_len, uio); 857 *mp = m; 858 mp = &m->m_next; 859 if (error == 0 && uio->uio_resid > 0) { 860 MGET(m, M_DONTWAIT, MT_DATA); 861 if (m == NULL) { 862 error = ENOBUFS; 863 break; 864 } 865 mlen = MLEN; 866 } 867 } 868 if (error) { 869 if (top != NULL) 870 m_freem (top); 871 ifp->if_ierrors++; 872 goto out0; 873 } 874 875 top->m_pkthdr.len = tlen; 876 top->m_pkthdr.rcvif = ifp; 877 878 #if NBPFILTER > 0 879 if (ifp->if_bpf) 880 bpf_mtap_af(ifp->if_bpf, AF_INET, top); 881 #endif 882 883 s = splnet(); 884 simple_lock(&tp->tun_lock); 885 if ((tp->tun_flags & TUN_INITED) == 0) { 886 /* Interface was destroyed */ 887 error = ENXIO; 888 goto out; 889 } 890 if (IF_QFULL(ifq)) { 891 IF_DROP(ifq); 892 ifp->if_collisions++; 893 m_freem(top); 894 error = ENOBUFS; 895 goto out; 896 } 897 898 IF_ENQUEUE(ifq, top); 899 ifp->if_ipackets++; 900 ifp->if_ibytes += tlen; 901 schednetisr(isr); 902 out: 903 simple_unlock(&tp->tun_lock); 904 out_nolock: 905 splx(s); 906 out0: 907 return (error); 908 } 909 910 #ifdef ALTQ 911 /* 912 * Start packet transmission on the interface. 913 * when the interface queue is rate-limited by ALTQ or TBR, 914 * if_start is needed to drain packets from the queue in order 915 * to notify readers when outgoing packets become ready. 916 * 917 * Should be called at splnet. 918 */ 919 static void 920 tunstart(ifp) 921 struct ifnet *ifp; 922 { 923 struct tun_softc *tp = ifp->if_softc; 924 925 if (!ALTQ_IS_ENABLED(&ifp->if_snd) && !TBR_IS_ENABLED(&ifp->if_snd)) 926 return; 927 928 simple_lock(&tp->tun_lock); 929 if (!IF_IS_EMPTY(&ifp->if_snd)) { 930 if (tp->tun_flags & TUN_RWAIT) { 931 tp->tun_flags &= ~TUN_RWAIT; 932 wakeup((caddr_t)tp); 933 } 934 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 935 fownsignal(tp->tun_pgid, SIGIO, POLL_OUT, 936 POLLOUT|POLLWRNORM, NULL); 937 938 selwakeup(&tp->tun_rsel); 939 } 940 simple_unlock(&tp->tun_lock); 941 } 942 #endif /* ALTQ */ 943 /* 944 * tunpoll - the poll interface, this is only useful on reads 945 * really. The write detect always returns true, write never blocks 946 * anyway, it either accepts the packet or drops it. 947 */ 948 int 949 tunpoll(dev, events, p) 950 dev_t dev; 951 int events; 952 struct proc *p; 953 { 954 struct tun_softc *tp; 955 struct ifnet *ifp; 956 int s, revents = 0; 957 958 s = splnet(); 959 tp = tun_find_unit(dev); 960 961 /* interface was "destroyed" already */ 962 if (tp == NULL) 963 goto out_nolock; 964 965 ifp = &tp->tun_if; 966 967 TUNDEBUG("%s: tunpoll\n", ifp->if_xname); 968 969 if (events & (POLLIN | POLLRDNORM)) { 970 if (!IFQ_IS_EMPTY(&ifp->if_snd)) { 971 TUNDEBUG("%s: tunpoll q=%d\n", ifp->if_xname, 972 ifp->if_snd.ifq_len); 973 revents |= events & (POLLIN | POLLRDNORM); 974 } else { 975 TUNDEBUG("%s: tunpoll waiting\n", ifp->if_xname); 976 selrecord(p, &tp->tun_rsel); 977 } 978 } 979 980 if (events & (POLLOUT | POLLWRNORM)) 981 revents |= events & (POLLOUT | POLLWRNORM); 982 983 simple_unlock(&tp->tun_lock); 984 out_nolock: 985 splx(s); 986 return (revents); 987 } 988 989 static void 990 filt_tunrdetach(struct knote *kn) 991 { 992 struct tun_softc *tp = kn->kn_hook; 993 int s; 994 995 s = splnet(); 996 SLIST_REMOVE(&tp->tun_rsel.sel_klist, kn, knote, kn_selnext); 997 splx(s); 998 } 999 1000 static int 1001 filt_tunread(struct knote *kn, long hint) 1002 { 1003 struct tun_softc *tp = kn->kn_hook; 1004 struct ifnet *ifp = &tp->tun_if; 1005 struct mbuf *m; 1006 int s; 1007 1008 s = splnet(); 1009 IF_POLL(&ifp->if_snd, m); 1010 if (m == NULL) { 1011 splx(s); 1012 return (0); 1013 } 1014 1015 for (kn->kn_data = 0; m != NULL; m = m->m_next) 1016 kn->kn_data += m->m_len; 1017 1018 splx(s); 1019 return (1); 1020 } 1021 1022 static const struct filterops tunread_filtops = 1023 { 1, NULL, filt_tunrdetach, filt_tunread }; 1024 1025 static const struct filterops tun_seltrue_filtops = 1026 { 1, NULL, filt_tunrdetach, filt_seltrue }; 1027 1028 int 1029 tunkqfilter(dev_t dev, struct knote *kn) 1030 { 1031 struct tun_softc *tp; 1032 struct klist *klist; 1033 int rv = 0, s; 1034 1035 s = splnet(); 1036 tp = tun_find_unit(dev); 1037 if (tp == NULL) 1038 goto out_nolock; 1039 1040 switch (kn->kn_filter) { 1041 case EVFILT_READ: 1042 klist = &tp->tun_rsel.sel_klist; 1043 kn->kn_fop = &tunread_filtops; 1044 break; 1045 1046 case EVFILT_WRITE: 1047 klist = &tp->tun_rsel.sel_klist; 1048 kn->kn_fop = &tun_seltrue_filtops; 1049 break; 1050 1051 default: 1052 rv = 1; 1053 goto out; 1054 } 1055 1056 kn->kn_hook = tp; 1057 1058 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 1059 1060 out: 1061 simple_unlock(&tp->tun_lock); 1062 out_nolock: 1063 splx(s); 1064 return (rv); 1065 } 1066