if_tun.c revision 1.73
1 /* $NetBSD: if_tun.c,v 1.73 2004/12/04 18:31:43 peter 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 1.73 2004/12/04 18:31:43 peter 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 int 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 int 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 return (0); 276 } 277 278 /* 279 * tunnel open - must be superuser & the device must be 280 * configured in 281 */ 282 int 283 tunopen(dev, flag, mode, p) 284 dev_t dev; 285 int flag, mode; 286 struct proc *p; 287 { 288 struct ifnet *ifp; 289 struct tun_softc *tp; 290 int s, error; 291 292 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0) 293 return (error); 294 295 if (NTUN < 1) 296 return (ENXIO); 297 298 s = splnet(); 299 tp = tun_find_unit(dev); 300 301 if (tp == NULL) { 302 (void)tun_clone_create(&tun_cloner, minor(dev)); 303 tp = tun_find_unit(dev); 304 if (tp == NULL) { 305 error = ENXIO; 306 goto out_nolock; 307 } 308 } 309 310 if (tp->tun_flags & TUN_OPEN) { 311 error = EBUSY; 312 goto out; 313 } 314 315 ifp = &tp->tun_if; 316 tp->tun_flags |= TUN_OPEN; 317 TUNDEBUG("%s: open\n", ifp->if_xname); 318 out: 319 simple_unlock(&tp->tun_lock); 320 out_nolock: 321 splx(s); 322 return (error); 323 } 324 325 /* 326 * tunclose - close the device - mark i/f down & delete 327 * routing info 328 */ 329 int 330 tunclose(dev, flag, mode, p) 331 dev_t dev; 332 int flag; 333 int mode; 334 struct proc *p; 335 { 336 int s; 337 struct tun_softc *tp; 338 struct ifnet *ifp; 339 340 s = splnet(); 341 if ((tp = tun_find_zunit(minor(dev))) != NULL) { 342 /* interface was "destroyed" before the close */ 343 free(tp, M_DEVBUF); 344 goto out_nolock; 345 } 346 347 if ((tp = tun_find_unit(dev)) == NULL) 348 goto out_nolock; 349 350 ifp = &tp->tun_if; 351 352 tp->tun_flags &= ~TUN_OPEN; 353 354 /* 355 * junk all pending output 356 */ 357 IFQ_PURGE(&ifp->if_snd); 358 359 if (ifp->if_flags & IFF_UP) { 360 if_down(ifp); 361 if (ifp->if_flags & IFF_RUNNING) { 362 /* find internet addresses and delete routes */ 363 struct ifaddr *ifa; 364 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 365 #ifdef INET 366 if (ifa->ifa_addr->sa_family == AF_INET) { 367 rtinit(ifa, (int)RTM_DELETE, 368 tp->tun_flags & TUN_DSTADDR 369 ? RTF_HOST 370 : 0); 371 } 372 #endif 373 } 374 } 375 } 376 tp->tun_pgid = 0; 377 selnotify(&tp->tun_rsel, 0); 378 379 TUNDEBUG ("%s: closed\n", ifp->if_xname); 380 simple_unlock(&tp->tun_lock); 381 out_nolock: 382 splx(s); 383 return (0); 384 } 385 386 /* 387 * Call at splnet() with tp locked. 388 */ 389 static void 390 tuninit(tp) 391 struct tun_softc *tp; 392 { 393 struct ifnet *ifp = &tp->tun_if; 394 struct ifaddr *ifa; 395 396 TUNDEBUG("%s: tuninit\n", ifp->if_xname); 397 398 ifp->if_flags |= IFF_UP | IFF_RUNNING; 399 400 tp->tun_flags &= ~(TUN_IASET|TUN_DSTADDR); 401 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 402 #ifdef INET 403 if (ifa->ifa_addr->sa_family == AF_INET) { 404 struct sockaddr_in *sin; 405 406 sin = satosin(ifa->ifa_addr); 407 if (sin && sin->sin_addr.s_addr) 408 tp->tun_flags |= TUN_IASET; 409 410 if (ifp->if_flags & IFF_POINTOPOINT) { 411 sin = satosin(ifa->ifa_dstaddr); 412 if (sin && sin->sin_addr.s_addr) 413 tp->tun_flags |= TUN_DSTADDR; 414 } 415 } 416 #endif 417 } 418 419 return; 420 } 421 422 /* 423 * Process an ioctl request. 424 */ 425 int 426 tun_ioctl(ifp, cmd, data) 427 struct ifnet *ifp; 428 u_long cmd; 429 caddr_t data; 430 { 431 int error = 0, s; 432 struct tun_softc *tp = (struct tun_softc *)(ifp->if_softc); 433 434 s = splnet(); 435 simple_lock(&tp->tun_lock); 436 437 switch (cmd) { 438 case SIOCSIFADDR: 439 tuninit(tp); 440 TUNDEBUG("%s: address set\n", ifp->if_xname); 441 break; 442 case SIOCSIFDSTADDR: 443 tuninit(tp); 444 TUNDEBUG("%s: destination address set\n", ifp->if_xname); 445 break; 446 case SIOCSIFBRDADDR: 447 TUNDEBUG("%s: broadcast address set\n", ifp->if_xname); 448 break; 449 case SIOCSIFMTU: { 450 struct ifreq *ifr = (struct ifreq *) data; 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 ifp->if_mtu = ifr->ifr_mtu; 457 break; 458 } 459 case SIOCADDMULTI: 460 case SIOCDELMULTI: { 461 struct ifreq *ifr = (struct ifreq *) data; 462 if (ifr == 0) { 463 error = EAFNOSUPPORT; /* XXX */ 464 break; 465 } 466 switch (ifr->ifr_addr.sa_family) { 467 #ifdef INET 468 case AF_INET: 469 break; 470 #endif 471 default: 472 error = EAFNOSUPPORT; 473 break; 474 } 475 break; 476 } 477 case SIOCSIFFLAGS: 478 break; 479 default: 480 error = EINVAL; 481 } 482 483 simple_unlock(&tp->tun_lock); 484 splx(s); 485 return (error); 486 } 487 488 /* 489 * tun_output - queue packets from higher level ready to put out. 490 */ 491 int 492 tun_output(ifp, m0, dst, rt) 493 struct ifnet *ifp; 494 struct mbuf *m0; 495 struct sockaddr *dst; 496 struct rtentry *rt; 497 { 498 struct tun_softc *tp = ifp->if_softc; 499 #ifdef INET 500 int s; 501 int error; 502 #endif 503 int mlen; 504 ALTQ_DECL(struct altq_pktattr pktattr;) 505 506 s = splnet(); 507 simple_lock(&tp->tun_lock); 508 TUNDEBUG ("%s: tun_output\n", ifp->if_xname); 509 510 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 511 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, 512 tp->tun_flags); 513 m_freem (m0); 514 error = EHOSTDOWN; 515 goto out; 516 } 517 518 /* 519 * if the queueing discipline needs packet classification, 520 * do it before prepending link headers. 521 */ 522 IFQ_CLASSIFY(&ifp->if_snd, m0, dst->sa_family, &pktattr); 523 524 #if NBPFILTER > 0 525 if (ifp->if_bpf) 526 bpf_mtap_af(ifp->if_bpf, dst->sa_family, m0); 527 #endif 528 529 switch(dst->sa_family) { 530 #ifdef INET 531 case AF_INET: 532 if (tp->tun_flags & TUN_PREPADDR) { 533 /* Simple link-layer header */ 534 M_PREPEND(m0, dst->sa_len, M_DONTWAIT); 535 if (m0 == NULL) { 536 IF_DROP(&ifp->if_snd); 537 error = ENOBUFS; 538 goto out; 539 } 540 bcopy(dst, mtod(m0, char *), dst->sa_len); 541 } 542 /* FALLTHROUGH */ 543 case AF_UNSPEC: 544 IFQ_ENQUEUE(&ifp->if_snd, m0, &pktattr, error); 545 if (error) { 546 ifp->if_collisions++; 547 error = EAFNOSUPPORT; 548 goto out; 549 } 550 mlen = m0->m_pkthdr.len; 551 ifp->if_opackets++; 552 ifp->if_obytes += mlen; 553 break; 554 #endif 555 default: 556 m_freem(m0); 557 error = EAFNOSUPPORT; 558 goto out; 559 } 560 561 if (tp->tun_flags & TUN_RWAIT) { 562 tp->tun_flags &= ~TUN_RWAIT; 563 wakeup((caddr_t)tp); 564 } 565 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 566 fownsignal(tp->tun_pgid, SIGIO, POLL_IN, POLLIN|POLLRDNORM, 567 NULL); 568 569 selnotify(&tp->tun_rsel, 0); 570 out: 571 simple_unlock(&tp->tun_lock); 572 splx(s); 573 return (0); 574 } 575 576 /* 577 * the cdevsw interface is now pretty minimal. 578 */ 579 int 580 tunioctl(dev, cmd, data, flag, p) 581 dev_t dev; 582 u_long cmd; 583 caddr_t data; 584 int flag; 585 struct proc *p; 586 { 587 struct tun_softc *tp; 588 int s, error = 0; 589 590 s = splnet(); 591 tp = tun_find_unit(dev); 592 593 /* interface was "destroyed" already */ 594 if (tp == NULL) { 595 error = ENXIO; 596 goto out_nolock; 597 } 598 599 switch (cmd) { 600 case TUNSDEBUG: 601 tundebug = *(int *)data; 602 break; 603 604 case TUNGDEBUG: 605 *(int *)data = tundebug; 606 break; 607 608 case TUNSIFMODE: 609 switch (*(int *)data & (IFF_POINTOPOINT|IFF_BROADCAST)) { 610 case IFF_POINTOPOINT: 611 case IFF_BROADCAST: 612 if (tp->tun_if.if_flags & IFF_UP) { 613 error = EBUSY; 614 goto out; 615 } 616 tp->tun_if.if_flags &= 617 ~(IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST); 618 tp->tun_if.if_flags |= *(int *)data; 619 break; 620 default: 621 error = EINVAL; 622 goto out; 623 } 624 break; 625 626 case TUNSLMODE: 627 if (*(int *)data) 628 tp->tun_flags |= TUN_PREPADDR; 629 else 630 tp->tun_flags &= ~TUN_PREPADDR; 631 break; 632 633 case FIONBIO: 634 if (*(int *)data) 635 tp->tun_flags |= TUN_NBIO; 636 else 637 tp->tun_flags &= ~TUN_NBIO; 638 break; 639 640 case FIOASYNC: 641 if (*(int *)data) 642 tp->tun_flags |= TUN_ASYNC; 643 else 644 tp->tun_flags &= ~TUN_ASYNC; 645 break; 646 647 case FIONREAD: 648 if (tp->tun_if.if_snd.ifq_head) 649 *(int *)data = tp->tun_if.if_snd.ifq_head->m_pkthdr.len; 650 else 651 *(int *)data = 0; 652 break; 653 654 case TIOCSPGRP: 655 case FIOSETOWN: 656 error = fsetown(p, &tp->tun_pgid, cmd, data); 657 break; 658 659 case TIOCGPGRP: 660 case FIOGETOWN: 661 error = fgetown(p, tp->tun_pgid, cmd, data); 662 break; 663 664 default: 665 error = ENOTTY; 666 } 667 668 out: 669 simple_unlock(&tp->tun_lock); 670 out_nolock: 671 splx(s); 672 return (error); 673 } 674 675 /* 676 * The cdevsw read interface - reads a packet at a time, or at 677 * least as much of a packet as can be read. 678 */ 679 int 680 tunread(dev, uio, ioflag) 681 dev_t dev; 682 struct uio *uio; 683 int ioflag; 684 { 685 struct tun_softc *tp; 686 struct ifnet *ifp; 687 struct mbuf *m, *m0; 688 int error = 0, len, s, index; 689 690 s = splnet(); 691 tp = tun_find_unit(dev); 692 693 /* interface was "destroyed" already */ 694 if (tp == NULL) { 695 error = ENXIO; 696 goto out_nolock; 697 } 698 699 index = tp->tun_if.if_index; 700 ifp = &tp->tun_if; 701 702 TUNDEBUG ("%s: read\n", ifp->if_xname); 703 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 704 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, tp->tun_flags); 705 error = EHOSTDOWN; 706 goto out; 707 } 708 709 tp->tun_flags &= ~TUN_RWAIT; 710 711 do { 712 IFQ_DEQUEUE(&ifp->if_snd, m0); 713 if (m0 == 0) { 714 if (tp->tun_flags & TUN_NBIO) { 715 error = EWOULDBLOCK; 716 goto out; 717 } 718 tp->tun_flags |= TUN_RWAIT; 719 if (ltsleep((caddr_t)tp, PZERO|PCATCH|PNORELOCK, 720 "tunread", 0, &tp->tun_lock) != 0) { 721 error = EINTR; 722 goto out_nolock; 723 } else { 724 /* 725 * Maybe the interface was destroyed while 726 * we were sleeping, so let's ensure that 727 * we're looking at the same (valid) tun 728 * interface before looping. 729 */ 730 tp = tun_find_unit(dev); 731 if (tp == NULL) { 732 error = ENXIO; 733 goto out_nolock; 734 } 735 if (tp->tun_if.if_index != index) { 736 error = ENXIO; 737 goto out; 738 } 739 } 740 } 741 } while (m0 == 0); 742 743 simple_unlock(&tp->tun_lock); 744 splx(s); 745 746 /* Copy the mbuf chain */ 747 while (m0 && uio->uio_resid > 0 && error == 0) { 748 len = min(uio->uio_resid, m0->m_len); 749 if (len != 0) 750 error = uiomove(mtod(m0, caddr_t), len, uio); 751 MFREE(m0, m); 752 m0 = m; 753 } 754 755 if (m0) { 756 TUNDEBUG("Dropping mbuf\n"); 757 m_freem(m0); 758 } 759 if (error) 760 ifp->if_ierrors++; 761 762 return (error); 763 764 out: 765 simple_unlock(&tp->tun_lock); 766 out_nolock: 767 splx(s); 768 return (error); 769 } 770 771 /* 772 * the cdevsw write interface - an atomic write is a packet - or else! 773 */ 774 int 775 tunwrite(dev, uio, ioflag) 776 dev_t dev; 777 struct uio *uio; 778 int ioflag; 779 { 780 struct tun_softc *tp; 781 struct ifnet *ifp; 782 struct mbuf *top, **mp, *m; 783 struct ifqueue *ifq; 784 struct sockaddr dst; 785 int isr, error = 0, s, tlen, mlen; 786 787 s = splnet(); 788 tp = tun_find_unit(dev); 789 790 /* interface was "destroyed" already */ 791 if (tp == NULL) { 792 error = ENXIO; 793 goto out_nolock; 794 } 795 796 /* Unlock until we've got the data */ 797 simple_unlock(&tp->tun_lock); 798 splx(s); 799 800 ifp = &tp->tun_if; 801 802 TUNDEBUG("%s: tunwrite\n", ifp->if_xname); 803 804 if (tp->tun_flags & TUN_PREPADDR) { 805 if (uio->uio_resid < sizeof(dst)) { 806 error = EIO; 807 goto out0; 808 } 809 error = uiomove((caddr_t)&dst, sizeof(dst), uio); 810 if (dst.sa_len > sizeof(dst)) { 811 /* Duh.. */ 812 char discard; 813 int n = dst.sa_len - sizeof(dst); 814 while (n--) 815 if ((error = uiomove(&discard, 1, uio)) != 0) { 816 goto out0; 817 } 818 } 819 } else { 820 #ifdef INET 821 dst.sa_family = AF_INET; 822 #endif 823 } 824 825 if (uio->uio_resid > TUNMTU) { 826 TUNDEBUG("%s: len=%lu!\n", ifp->if_xname, 827 (unsigned long)uio->uio_resid); 828 error = EIO; 829 goto out0; 830 } 831 832 switch (dst.sa_family) { 833 #ifdef INET 834 case AF_INET: 835 ifq = &ipintrq; 836 isr = NETISR_IP; 837 break; 838 #endif 839 default: 840 error = EAFNOSUPPORT; 841 goto out0; 842 } 843 844 tlen = uio->uio_resid; 845 846 /* get a header mbuf */ 847 MGETHDR(m, M_DONTWAIT, MT_DATA); 848 if (m == NULL) { 849 error = ENOBUFS; 850 goto out0; 851 } 852 mlen = MHLEN; 853 854 top = NULL; 855 mp = ⊤ 856 while (error == 0 && uio->uio_resid > 0) { 857 m->m_len = min(mlen, uio->uio_resid); 858 error = uiomove(mtod(m, caddr_t), m->m_len, uio); 859 *mp = m; 860 mp = &m->m_next; 861 if (error == 0 && uio->uio_resid > 0) { 862 MGET(m, M_DONTWAIT, MT_DATA); 863 if (m == NULL) { 864 error = ENOBUFS; 865 break; 866 } 867 mlen = MLEN; 868 } 869 } 870 if (error) { 871 if (top != NULL) 872 m_freem (top); 873 ifp->if_ierrors++; 874 goto out0; 875 } 876 877 top->m_pkthdr.len = tlen; 878 top->m_pkthdr.rcvif = ifp; 879 880 #if NBPFILTER > 0 881 if (ifp->if_bpf) 882 bpf_mtap_af(ifp->if_bpf, AF_INET, top); 883 #endif 884 885 s = splnet(); 886 simple_lock(&tp->tun_lock); 887 if ((tp->tun_flags & TUN_INITED) == 0) { 888 /* Interface was destroyed */ 889 error = ENXIO; 890 goto out; 891 } 892 if (IF_QFULL(ifq)) { 893 IF_DROP(ifq); 894 ifp->if_collisions++; 895 m_freem(top); 896 error = ENOBUFS; 897 goto out; 898 } 899 900 IF_ENQUEUE(ifq, top); 901 ifp->if_ipackets++; 902 ifp->if_ibytes += tlen; 903 schednetisr(isr); 904 out: 905 simple_unlock(&tp->tun_lock); 906 out_nolock: 907 splx(s); 908 out0: 909 return (error); 910 } 911 912 #ifdef ALTQ 913 /* 914 * Start packet transmission on the interface. 915 * when the interface queue is rate-limited by ALTQ or TBR, 916 * if_start is needed to drain packets from the queue in order 917 * to notify readers when outgoing packets become ready. 918 * 919 * Should be called at splnet. 920 */ 921 static void 922 tunstart(ifp) 923 struct ifnet *ifp; 924 { 925 struct tun_softc *tp = ifp->if_softc; 926 927 if (!ALTQ_IS_ENABLED(&ifp->if_snd) && !TBR_IS_ENABLED(&ifp->if_snd)) 928 return; 929 930 simple_lock(&tp->tun_lock); 931 if (!IF_IS_EMPTY(&ifp->if_snd)) { 932 if (tp->tun_flags & TUN_RWAIT) { 933 tp->tun_flags &= ~TUN_RWAIT; 934 wakeup((caddr_t)tp); 935 } 936 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 937 fownsignal(tp->tun_pgid, SIGIO, POLL_OUT, 938 POLLOUT|POLLWRNORM, NULL); 939 940 selwakeup(&tp->tun_rsel); 941 } 942 simple_unlock(&tp->tun_lock); 943 } 944 #endif /* ALTQ */ 945 /* 946 * tunpoll - the poll interface, this is only useful on reads 947 * really. The write detect always returns true, write never blocks 948 * anyway, it either accepts the packet or drops it. 949 */ 950 int 951 tunpoll(dev, events, p) 952 dev_t dev; 953 int events; 954 struct proc *p; 955 { 956 struct tun_softc *tp; 957 struct ifnet *ifp; 958 int s, revents = 0; 959 960 s = splnet(); 961 tp = tun_find_unit(dev); 962 963 /* interface was "destroyed" already */ 964 if (tp == NULL) 965 goto out_nolock; 966 967 ifp = &tp->tun_if; 968 969 TUNDEBUG("%s: tunpoll\n", ifp->if_xname); 970 971 if (events & (POLLIN | POLLRDNORM)) { 972 if (!IFQ_IS_EMPTY(&ifp->if_snd)) { 973 TUNDEBUG("%s: tunpoll q=%d\n", ifp->if_xname, 974 ifp->if_snd.ifq_len); 975 revents |= events & (POLLIN | POLLRDNORM); 976 } else { 977 TUNDEBUG("%s: tunpoll waiting\n", ifp->if_xname); 978 selrecord(p, &tp->tun_rsel); 979 } 980 } 981 982 if (events & (POLLOUT | POLLWRNORM)) 983 revents |= events & (POLLOUT | POLLWRNORM); 984 985 simple_unlock(&tp->tun_lock); 986 out_nolock: 987 splx(s); 988 return (revents); 989 } 990 991 static void 992 filt_tunrdetach(struct knote *kn) 993 { 994 struct tun_softc *tp = kn->kn_hook; 995 int s; 996 997 s = splnet(); 998 SLIST_REMOVE(&tp->tun_rsel.sel_klist, kn, knote, kn_selnext); 999 splx(s); 1000 } 1001 1002 static int 1003 filt_tunread(struct knote *kn, long hint) 1004 { 1005 struct tun_softc *tp = kn->kn_hook; 1006 struct ifnet *ifp = &tp->tun_if; 1007 struct mbuf *m; 1008 int s; 1009 1010 s = splnet(); 1011 IF_POLL(&ifp->if_snd, m); 1012 if (m == NULL) { 1013 splx(s); 1014 return (0); 1015 } 1016 1017 for (kn->kn_data = 0; m != NULL; m = m->m_next) 1018 kn->kn_data += m->m_len; 1019 1020 splx(s); 1021 return (1); 1022 } 1023 1024 static const struct filterops tunread_filtops = 1025 { 1, NULL, filt_tunrdetach, filt_tunread }; 1026 1027 static const struct filterops tun_seltrue_filtops = 1028 { 1, NULL, filt_tunrdetach, filt_seltrue }; 1029 1030 int 1031 tunkqfilter(dev_t dev, struct knote *kn) 1032 { 1033 struct tun_softc *tp; 1034 struct klist *klist; 1035 int rv = 0, s; 1036 1037 s = splnet(); 1038 tp = tun_find_unit(dev); 1039 if (tp == NULL) 1040 goto out_nolock; 1041 1042 switch (kn->kn_filter) { 1043 case EVFILT_READ: 1044 klist = &tp->tun_rsel.sel_klist; 1045 kn->kn_fop = &tunread_filtops; 1046 break; 1047 1048 case EVFILT_WRITE: 1049 klist = &tp->tun_rsel.sel_klist; 1050 kn->kn_fop = &tun_seltrue_filtops; 1051 break; 1052 1053 default: 1054 rv = 1; 1055 goto out; 1056 } 1057 1058 kn->kn_hook = tp; 1059 1060 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 1061 1062 out: 1063 simple_unlock(&tp->tun_lock); 1064 out_nolock: 1065 splx(s); 1066 return (rv); 1067 } 1068
Indexes created Thu Sep 25 16:09:42 GMT 2025