if_tun.c revision 127580
1/* $NetBSD: if_tun.c,v 1.14 1994/06/29 06:36:25 cgd 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 it's 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 * $FreeBSD: head/sys/net/if_tun.c 127580 2004-03-29 18:42:51Z rwatson $ 17 */ 18 19#include "opt_atalk.h" 20#include "opt_inet.h" 21#include "opt_inet6.h" 22#include "opt_ipx.h" 23#include "opt_mac.h" 24 25#include <sys/param.h> 26#include <sys/proc.h> 27#include <sys/systm.h> 28#include <sys/mac.h> 29#include <sys/mbuf.h> 30#include <sys/module.h> 31#include <sys/socket.h> 32#include <sys/filio.h> 33#include <sys/sockio.h> 34#include <sys/ttycom.h> 35#include <sys/poll.h> 36#include <sys/signalvar.h> 37#include <sys/filedesc.h> 38#include <sys/kernel.h> 39#include <sys/sysctl.h> 40#include <sys/conf.h> 41#include <sys/uio.h> 42#include <sys/vnode.h> 43#include <sys/malloc.h> 44#include <sys/random.h> 45 46#include <net/if.h> 47#include <net/if_types.h> 48#include <net/netisr.h> 49#include <net/route.h> 50#ifdef INET 51#include <netinet/in.h> 52#endif 53#include <net/bpf.h> 54#include <net/if_tun.h> 55 56#include <sys/queue.h> 57 58struct tun_softc { 59 TAILQ_ENTRY(tun_softc) tun_list; 60 dev_t tun_dev; 61 u_short tun_flags; /* misc flags */ 62#define TUN_OPEN 0x0001 63#define TUN_INITED 0x0002 64#define TUN_RCOLL 0x0004 65#define TUN_IASET 0x0008 66#define TUN_DSTADDR 0x0010 67#define TUN_LMODE 0x0020 68#define TUN_RWAIT 0x0040 69#define TUN_ASYNC 0x0080 70#define TUN_IFHEAD 0x0100 71 72#define TUN_READY (TUN_OPEN | TUN_INITED) 73 74 /* 75 * XXXRW: tun_pid is used to exclusively lock /dev/tun. Is this 76 * actually needed? Can we just return EBUSY if already open? 77 * Problem is that this involved inherent races when a tun device 78 * is handed off from one process to another, as opposed to just 79 * being slightly stale informationally. 80 */ 81 pid_t tun_pid; /* owning pid */ 82 struct ifnet tun_if; /* the interface */ 83 struct sigio *tun_sigio; /* information for async I/O */ 84 struct selinfo tun_rsel; /* read select */ 85}; 86 87#define TUNDEBUG if (tundebug) if_printf 88#define TUNNAME "tun" 89 90/* 91 * All mutable global variables in if_tun are locked using tunmtx, with 92 * the exception of tundebug, which is used unlocked, and tunclones, 93 * which is static after setup. 94 */ 95static struct mtx tunmtx; 96static MALLOC_DEFINE(M_TUN, TUNNAME, "Tunnel Interface"); 97static int tundebug = 0; 98static struct clonedevs *tunclones; 99static TAILQ_HEAD(,tun_softc) tunhead = TAILQ_HEAD_INITIALIZER(tunhead); 100SYSCTL_INT(_debug, OID_AUTO, if_tun_debug, CTLFLAG_RW, &tundebug, 0, ""); 101 102static void tunclone(void *arg, char *name, int namelen, dev_t *dev); 103static void tuncreate(dev_t dev); 104static int tunifioctl(struct ifnet *, u_long, caddr_t); 105static int tuninit(struct ifnet *); 106static int tunmodevent(module_t, int, void *); 107static int tunoutput(struct ifnet *, struct mbuf *, struct sockaddr *, 108 struct rtentry *rt); 109static void tunstart(struct ifnet *); 110 111static d_open_t tunopen; 112static d_close_t tunclose; 113static d_read_t tunread; 114static d_write_t tunwrite; 115static d_ioctl_t tunioctl; 116static d_poll_t tunpoll; 117 118static struct cdevsw tun_cdevsw = { 119 .d_version = D_VERSION, 120 .d_flags = D_PSEUDO | D_NEEDGIANT, 121 .d_open = tunopen, 122 .d_close = tunclose, 123 .d_read = tunread, 124 .d_write = tunwrite, 125 .d_ioctl = tunioctl, 126 .d_poll = tunpoll, 127 .d_name = TUNNAME, 128}; 129 130static void 131tunclone(void *arg, char *name, int namelen, dev_t *dev) 132{ 133 int u, i; 134 135 if (*dev != NODEV) 136 return; 137 138 if (strcmp(name, TUNNAME) == 0) { 139 u = -1; 140 } else if (dev_stdclone(name, NULL, TUNNAME, &u) != 1) 141 return; /* Don't recognise the name */ 142 if (u != -1 && u > IF_MAXUNIT) 143 return; /* Unit number too high */ 144 145 /* find any existing device, or allocate new unit number */ 146 i = clone_create(&tunclones, &tun_cdevsw, &u, dev, 0); 147 if (i) { 148 /* No preexisting dev_t, create one */ 149 *dev = make_dev(&tun_cdevsw, unit2minor(u), 150 UID_UUCP, GID_DIALER, 0600, "tun%d", u); 151 if (*dev != NULL) 152 (*dev)->si_flags |= SI_CHEAPCLONE; 153 } 154} 155 156static void 157tun_destroy(struct tun_softc *tp) 158{ 159 dev_t dev; 160 161 KASSERT((tp->tun_flags & TUN_OPEN) == 0, 162 ("tununits is out of sync - unit %d", tp->tun_if.if_dunit)); 163 164 dev = tp->tun_dev; 165 bpfdetach(&tp->tun_if); 166 if_detach(&tp->tun_if); 167 destroy_dev(dev); 168 free(tp, M_TUN); 169} 170 171static int 172tunmodevent(module_t mod, int type, void *data) 173{ 174 static eventhandler_tag tag; 175 struct tun_softc *tp; 176 177 switch (type) { 178 case MOD_LOAD: 179 mtx_init(&tunmtx, "tunmtx", NULL, MTX_DEF); 180 clone_setup(&tunclones); 181 tag = EVENTHANDLER_REGISTER(dev_clone, tunclone, 0, 1000); 182 if (tag == NULL) 183 return (ENOMEM); 184 break; 185 case MOD_UNLOAD: 186 EVENTHANDLER_DEREGISTER(dev_clone, tag); 187 188 mtx_lock(&tunmtx); 189 while ((tp = TAILQ_FIRST(&tunhead)) != NULL) { 190 TAILQ_REMOVE(&tunhead, tp, tun_list); 191 mtx_unlock(&tunmtx); 192 tun_destroy(tp); 193 mtx_lock(&tunmtx); 194 } 195 mtx_unlock(&tunmtx); 196 clone_cleanup(&tunclones); 197 mtx_destroy(&tunmtx); 198 break; 199 } 200 return 0; 201} 202 203static moduledata_t tun_mod = { 204 "if_tun", 205 tunmodevent, 206 0 207}; 208 209DECLARE_MODULE(if_tun, tun_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 210 211static void 212tunstart(struct ifnet *ifp) 213{ 214 struct tun_softc *tp = ifp->if_softc; 215 216 if (tp->tun_flags & TUN_RWAIT) { 217 tp->tun_flags &= ~TUN_RWAIT; 218 wakeup(tp); 219 } 220 if (tp->tun_flags & TUN_ASYNC && tp->tun_sigio) 221 pgsigio(&tp->tun_sigio, SIGIO, 0); 222 selwakeuppri(&tp->tun_rsel, PZERO + 1); 223} 224 225static void 226tuncreate(dev_t dev) 227{ 228 struct tun_softc *sc; 229 struct ifnet *ifp; 230 231 dev->si_flags &= ~SI_CHEAPCLONE; 232 233 MALLOC(sc, struct tun_softc *, sizeof(*sc), M_TUN, M_WAITOK | M_ZERO); 234 sc->tun_flags = TUN_INITED; 235 sc->tun_dev = dev; 236 mtx_lock(&tunmtx); 237 TAILQ_INSERT_TAIL(&tunhead, sc, tun_list); 238 mtx_unlock(&tunmtx); 239 240 ifp = &sc->tun_if; 241 if_initname(ifp, TUNNAME, dev2unit(dev)); 242 ifp->if_mtu = TUNMTU; 243 ifp->if_ioctl = tunifioctl; 244 ifp->if_output = tunoutput; 245 ifp->if_start = tunstart; 246 ifp->if_flags = IFF_POINTOPOINT | IFF_MULTICAST; 247 ifp->if_type = IFT_PPP; 248 ifp->if_snd.ifq_maxlen = ifqmaxlen; 249 ifp->if_softc = sc; 250 if_attach(ifp); 251 bpfattach(ifp, DLT_NULL, sizeof(u_int)); 252 dev->si_drv1 = sc; 253} 254 255static int 256tunopen(dev_t dev, int flag, int mode, struct thread *td) 257{ 258 struct ifnet *ifp; 259 struct tun_softc *tp; 260 261 tp = dev->si_drv1; 262 if (!tp) { 263 tuncreate(dev); 264 tp = dev->si_drv1; 265 } 266 267 if (tp->tun_pid != 0 && tp->tun_pid != td->td_proc->p_pid) 268 return (EBUSY); 269 tp->tun_pid = td->td_proc->p_pid; 270 271 tp->tun_flags |= TUN_OPEN; 272 ifp = &tp->tun_if; 273 TUNDEBUG(ifp, "open\n"); 274 275 return (0); 276} 277 278/* 279 * tunclose - close the device - mark i/f down & delete 280 * routing info 281 */ 282static int 283tunclose(dev_t dev, int foo, int bar, struct thread *td) 284{ 285 struct tun_softc *tp; 286 struct ifnet *ifp; 287 int s; 288 289 tp = dev->si_drv1; 290 ifp = &tp->tun_if; 291 292 tp->tun_flags &= ~TUN_OPEN; 293 tp->tun_pid = 0; 294 295 /* 296 * junk all pending output 297 */ 298 IF_DRAIN(&ifp->if_snd); 299 300 if (ifp->if_flags & IFF_UP) { 301 s = splimp(); 302 if_down(ifp); 303 splx(s); 304 } 305 306 if (ifp->if_flags & IFF_RUNNING) { 307 struct ifaddr *ifa; 308 309 s = splimp(); 310 /* find internet addresses and delete routes */ 311 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) 312 if (ifa->ifa_addr->sa_family == AF_INET) 313 rtinit(ifa, (int)RTM_DELETE, 314 tp->tun_flags & TUN_DSTADDR ? RTF_HOST : 0); 315 ifp->if_flags &= ~IFF_RUNNING; 316 splx(s); 317 } 318 319 funsetown(&tp->tun_sigio); 320 selwakeuppri(&tp->tun_rsel, PZERO + 1); 321 TUNDEBUG (ifp, "closed\n"); 322 return (0); 323} 324 325static int 326tuninit(struct ifnet *ifp) 327{ 328 struct tun_softc *tp = ifp->if_softc; 329 struct ifaddr *ifa; 330 int error = 0; 331 332 TUNDEBUG(ifp, "tuninit\n"); 333 334 ifp->if_flags |= IFF_UP | IFF_RUNNING; 335 getmicrotime(&ifp->if_lastchange); 336 337 for (ifa = TAILQ_FIRST(&ifp->if_addrhead); ifa; 338 ifa = TAILQ_NEXT(ifa, ifa_link)) { 339 if (ifa->ifa_addr == NULL) 340 error = EFAULT; 341 /* XXX: Should maybe return straight off? */ 342 else { 343#ifdef INET 344 if (ifa->ifa_addr->sa_family == AF_INET) { 345 struct sockaddr_in *si; 346 347 si = (struct sockaddr_in *)ifa->ifa_addr; 348 if (si->sin_addr.s_addr) 349 tp->tun_flags |= TUN_IASET; 350 351 si = (struct sockaddr_in *)ifa->ifa_dstaddr; 352 if (si && si->sin_addr.s_addr) 353 tp->tun_flags |= TUN_DSTADDR; 354 } 355#endif 356 } 357 } 358 return (error); 359} 360 361/* 362 * Process an ioctl request. 363 */ 364static int 365tunifioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 366{ 367 struct ifreq *ifr = (struct ifreq *)data; 368 struct tun_softc *tp = ifp->if_softc; 369 struct ifstat *ifs; 370 int error = 0, s; 371 372 s = splimp(); 373 switch(cmd) { 374 case SIOCGIFSTATUS: 375 ifs = (struct ifstat *)data; 376 if (tp->tun_pid) 377 sprintf(ifs->ascii + strlen(ifs->ascii), 378 "\tOpened by PID %d\n", tp->tun_pid); 379 break; 380 case SIOCSIFADDR: 381 error = tuninit(ifp); 382 TUNDEBUG(ifp, "address set, error=%d\n", error); 383 break; 384 case SIOCSIFDSTADDR: 385 error = tuninit(ifp); 386 TUNDEBUG(ifp, "destination address set, error=%d\n", error); 387 break; 388 case SIOCSIFMTU: 389 ifp->if_mtu = ifr->ifr_mtu; 390 TUNDEBUG(ifp, "mtu set\n"); 391 break; 392 case SIOCSIFFLAGS: 393 case SIOCADDMULTI: 394 case SIOCDELMULTI: 395 break; 396 default: 397 error = EINVAL; 398 } 399 splx(s); 400 return (error); 401} 402 403/* 404 * tunoutput - queue packets from higher level ready to put out. 405 */ 406static int 407tunoutput( 408 struct ifnet *ifp, 409 struct mbuf *m0, 410 struct sockaddr *dst, 411 struct rtentry *rt) 412{ 413 struct tun_softc *tp = ifp->if_softc; 414#ifdef MAC 415 int error; 416#endif 417 418 TUNDEBUG (ifp, "tunoutput\n"); 419 420#ifdef MAC 421 error = mac_check_ifnet_transmit(ifp, m0); 422 if (error) { 423 m_freem(m0); 424 return (error); 425 } 426#endif 427 428 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 429 TUNDEBUG (ifp, "not ready 0%o\n", tp->tun_flags); 430 m_freem (m0); 431 return (EHOSTDOWN); 432 } 433 434 if ((ifp->if_flags & IFF_UP) != IFF_UP) { 435 m_freem (m0); 436 return (EHOSTDOWN); 437 } 438 439 /* BPF write needs to be handled specially */ 440 if (dst->sa_family == AF_UNSPEC) { 441 dst->sa_family = *(mtod(m0, int *)); 442 m0->m_len -= sizeof(int); 443 m0->m_pkthdr.len -= sizeof(int); 444 m0->m_data += sizeof(int); 445 } 446 447 if (ifp->if_bpf) { 448 uint32_t af = dst->sa_family; 449 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m0); 450 } 451 452 /* prepend sockaddr? this may abort if the mbuf allocation fails */ 453 if (tp->tun_flags & TUN_LMODE) { 454 /* allocate space for sockaddr */ 455 M_PREPEND(m0, dst->sa_len, M_DONTWAIT); 456 457 /* if allocation failed drop packet */ 458 if (m0 == NULL) { 459 ifp->if_iqdrops++; 460 ifp->if_oerrors++; 461 return (ENOBUFS); 462 } else { 463 bcopy(dst, m0->m_data, dst->sa_len); 464 } 465 } 466 467 if (tp->tun_flags & TUN_IFHEAD) { 468 /* Prepend the address family */ 469 M_PREPEND(m0, 4, M_DONTWAIT); 470 471 /* if allocation failed drop packet */ 472 if (m0 == NULL) { 473 ifp->if_iqdrops++; 474 ifp->if_oerrors++; 475 return (ENOBUFS); 476 } else 477 *(u_int32_t *)m0->m_data = htonl(dst->sa_family); 478 } else { 479#ifdef INET 480 if (dst->sa_family != AF_INET) 481#endif 482 { 483 m_freem(m0); 484 return (EAFNOSUPPORT); 485 } 486 } 487 488 if (! IF_HANDOFF(&ifp->if_snd, m0, ifp)) { 489 ifp->if_collisions++; 490 return (ENOBUFS); 491 } 492 ifp->if_opackets++; 493 return (0); 494} 495 496/* 497 * the cdevsw interface is now pretty minimal. 498 */ 499static int 500tunioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct thread *td) 501{ 502 int s; 503 int error; 504 struct tun_softc *tp = dev->si_drv1; 505 struct tuninfo *tunp; 506 507 switch (cmd) { 508 case TUNSIFINFO: 509 tunp = (struct tuninfo *)data; 510 if (tunp->mtu < IF_MINMTU) 511 return (EINVAL); 512 if (tp->tun_if.if_mtu != tunp->mtu 513 && (error = suser(td)) != 0) 514 return (error); 515 tp->tun_if.if_mtu = tunp->mtu; 516 tp->tun_if.if_type = tunp->type; 517 tp->tun_if.if_baudrate = tunp->baudrate; 518 break; 519 case TUNGIFINFO: 520 tunp = (struct tuninfo *)data; 521 tunp->mtu = tp->tun_if.if_mtu; 522 tunp->type = tp->tun_if.if_type; 523 tunp->baudrate = tp->tun_if.if_baudrate; 524 break; 525 case TUNSDEBUG: 526 tundebug = *(int *)data; 527 break; 528 case TUNGDEBUG: 529 *(int *)data = tundebug; 530 break; 531 case TUNSLMODE: 532 if (*(int *)data) { 533 tp->tun_flags |= TUN_LMODE; 534 tp->tun_flags &= ~TUN_IFHEAD; 535 } else 536 tp->tun_flags &= ~TUN_LMODE; 537 break; 538 case TUNSIFHEAD: 539 if (*(int *)data) { 540 tp->tun_flags |= TUN_IFHEAD; 541 tp->tun_flags &= ~TUN_LMODE; 542 } else 543 tp->tun_flags &= ~TUN_IFHEAD; 544 break; 545 case TUNGIFHEAD: 546 *(int *)data = (tp->tun_flags & TUN_IFHEAD) ? 1 : 0; 547 break; 548 case TUNSIFMODE: 549 /* deny this if UP */ 550 if (tp->tun_if.if_flags & IFF_UP) 551 return(EBUSY); 552 553 switch (*(int *)data & ~IFF_MULTICAST) { 554 case IFF_POINTOPOINT: 555 case IFF_BROADCAST: 556 tp->tun_if.if_flags &= 557 ~(IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST); 558 tp->tun_if.if_flags |= *(int *)data; 559 break; 560 default: 561 return(EINVAL); 562 } 563 break; 564 case TUNSIFPID: 565 tp->tun_pid = curthread->td_proc->p_pid; 566 break; 567 case FIONBIO: 568 break; 569 case FIOASYNC: 570 if (*(int *)data) 571 tp->tun_flags |= TUN_ASYNC; 572 else 573 tp->tun_flags &= ~TUN_ASYNC; 574 break; 575 case FIONREAD: 576 s = splimp(); 577 if (tp->tun_if.if_snd.ifq_head) { 578 struct mbuf *mb = tp->tun_if.if_snd.ifq_head; 579 for( *(int *)data = 0; mb != 0; mb = mb->m_next) 580 *(int *)data += mb->m_len; 581 } else 582 *(int *)data = 0; 583 splx(s); 584 break; 585 case FIOSETOWN: 586 return (fsetown(*(int *)data, &tp->tun_sigio)); 587 588 case FIOGETOWN: 589 *(int *)data = fgetown(&tp->tun_sigio); 590 return (0); 591 592 /* This is deprecated, FIOSETOWN should be used instead. */ 593 case TIOCSPGRP: 594 return (fsetown(-(*(int *)data), &tp->tun_sigio)); 595 596 /* This is deprecated, FIOGETOWN should be used instead. */ 597 case TIOCGPGRP: 598 *(int *)data = -fgetown(&tp->tun_sigio); 599 return (0); 600 601 default: 602 return (ENOTTY); 603 } 604 return (0); 605} 606 607/* 608 * The cdevsw read interface - reads a packet at a time, or at 609 * least as much of a packet as can be read. 610 */ 611static int 612tunread(dev_t dev, struct uio *uio, int flag) 613{ 614 struct tun_softc *tp = dev->si_drv1; 615 struct ifnet *ifp = &tp->tun_if; 616 struct mbuf *m; 617 int error=0, len, s; 618 619 TUNDEBUG (ifp, "read\n"); 620 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 621 TUNDEBUG (ifp, "not ready 0%o\n", tp->tun_flags); 622 return (EHOSTDOWN); 623 } 624 625 tp->tun_flags &= ~TUN_RWAIT; 626 627 s = splimp(); 628 do { 629 IF_DEQUEUE(&ifp->if_snd, m); 630 if (m == NULL) { 631 if (flag & IO_NDELAY) { 632 splx(s); 633 return (EWOULDBLOCK); 634 } 635 tp->tun_flags |= TUN_RWAIT; 636 if((error = tsleep(tp, PCATCH | (PZERO + 1), 637 "tunread", 0)) != 0) { 638 splx(s); 639 return (error); 640 } 641 } 642 } while (m == NULL); 643 splx(s); 644 645 while (m && uio->uio_resid > 0 && error == 0) { 646 len = min(uio->uio_resid, m->m_len); 647 if (len != 0) 648 error = uiomove(mtod(m, void *), len, uio); 649 m = m_free(m); 650 } 651 652 if (m) { 653 TUNDEBUG(ifp, "Dropping mbuf\n"); 654 m_freem(m); 655 } 656 return (error); 657} 658 659/* 660 * the cdevsw write interface - an atomic write is a packet - or else! 661 */ 662static int 663tunwrite(dev_t dev, struct uio *uio, int flag) 664{ 665 struct tun_softc *tp = dev->si_drv1; 666 struct ifnet *ifp = &tp->tun_if; 667 struct mbuf *top, **mp, *m; 668 int error=0, tlen, mlen; 669 uint32_t family; 670 int isr; 671 672 TUNDEBUG(ifp, "tunwrite\n"); 673 674 if ((ifp->if_flags & IFF_UP) != IFF_UP) 675 /* ignore silently */ 676 return (0); 677 678 if (uio->uio_resid == 0) 679 return (0); 680 681 if (uio->uio_resid < 0 || uio->uio_resid > TUNMRU) { 682 TUNDEBUG(ifp, "len=%d!\n", uio->uio_resid); 683 return (EIO); 684 } 685 tlen = uio->uio_resid; 686 687 /* get a header mbuf */ 688 MGETHDR(m, M_DONTWAIT, MT_DATA); 689 if (m == NULL) 690 return (ENOBUFS); 691 mlen = MHLEN; 692 693 top = 0; 694 mp = ⊤ 695 while (error == 0 && uio->uio_resid > 0) { 696 m->m_len = min(mlen, uio->uio_resid); 697 error = uiomove(mtod(m, void *), m->m_len, uio); 698 *mp = m; 699 mp = &m->m_next; 700 if (uio->uio_resid > 0) { 701 MGET (m, M_DONTWAIT, MT_DATA); 702 if (m == 0) { 703 error = ENOBUFS; 704 break; 705 } 706 mlen = MLEN; 707 } 708 } 709 if (error) { 710 if (top) 711 m_freem (top); 712 ifp->if_ierrors++; 713 return (error); 714 } 715 716 top->m_pkthdr.len = tlen; 717 top->m_pkthdr.rcvif = ifp; 718#ifdef MAC 719 mac_create_mbuf_from_ifnet(ifp, top); 720#endif 721 722 if (tp->tun_flags & TUN_IFHEAD) { 723 if (top->m_len < sizeof(family) && 724 (top = m_pullup(top, sizeof(family))) == NULL) 725 return (ENOBUFS); 726 family = ntohl(*mtod(top, u_int32_t *)); 727 m_adj(top, sizeof(family)); 728 } else 729 family = AF_INET; 730 731 BPF_MTAP2(ifp, &family, sizeof(family), top); 732 733 switch (family) { 734#ifdef INET 735 case AF_INET: 736 isr = NETISR_IP; 737 break; 738#endif 739#ifdef INET6 740 case AF_INET6: 741 isr = NETISR_IPV6; 742 break; 743#endif 744#ifdef IPX 745 case AF_IPX: 746 isr = NETISR_IPX; 747 break; 748#endif 749#ifdef NETATALK 750 case AF_APPLETALK: 751 isr = NETISR_ATALK2; 752 break; 753#endif 754 default: 755 m_freem(m); 756 return (EAFNOSUPPORT); 757 } 758 /* First chunk of an mbuf contains good junk */ 759 if (harvest.point_to_point) 760 random_harvest(m, 16, 3, 0, RANDOM_NET); 761 ifp->if_ibytes += top->m_pkthdr.len; 762 ifp->if_ipackets++; 763 netisr_dispatch(isr, top); 764 return (0); 765} 766 767/* 768 * tunpoll - the poll interface, this is only useful on reads 769 * really. The write detect always returns true, write never blocks 770 * anyway, it either accepts the packet or drops it. 771 */ 772static int 773tunpoll(dev_t dev, int events, struct thread *td) 774{ 775 int s; 776 struct tun_softc *tp = dev->si_drv1; 777 struct ifnet *ifp = &tp->tun_if; 778 int revents = 0; 779 780 s = splimp(); 781 TUNDEBUG(ifp, "tunpoll\n"); 782 783 if (events & (POLLIN | POLLRDNORM)) { 784 if (ifp->if_snd.ifq_len > 0) { 785 TUNDEBUG(ifp, "tunpoll q=%d\n", ifp->if_snd.ifq_len); 786 revents |= events & (POLLIN | POLLRDNORM); 787 } else { 788 TUNDEBUG(ifp, "tunpoll waiting\n"); 789 selrecord(td, &tp->tun_rsel); 790 } 791 } 792 if (events & (POLLOUT | POLLWRNORM)) 793 revents |= events & (POLLOUT | POLLWRNORM); 794 795 splx(s); 796 return (revents); 797} 798