sys/net/tap/if_tap.c

   1 /*
   2  * Copyright (C) 1999-2000 by Maksim Yevmenkin <m_evmenkin@yahoo.com>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  * BASED ON:
  27  * -------------------------------------------------------------------------
  28  *
  29  * Copyright (c) 1988, Julian Onions <jpo@cs.nott.ac.uk>
  30  * Nottingham University 1987.
  31  */
  32
  33 /*
  34  * $FreeBSD: src/sys/net/if_tap.c,v 1.3.2.3 2002/04/14 21:41:48 luigi Exp $
  35  * $Id: if_tap.c,v 0.21 2000/07/23 21:46:02 max Exp $
  36  */
  37
  38 #include "opt_inet.h"
  39
  40 #include <sys/param.h>
  41 #include <sys/conf.h>
  42 #include <sys/device.h>
  43 #include <sys/filedesc.h>
  44 #include <sys/filio.h>
  45 #include <sys/kernel.h>
  46 #include <sys/malloc.h>
  47 #include <sys/mbuf.h>
  48 #include <sys/proc.h>
  49 #include <sys/caps.h>
  50 #include <sys/signalvar.h>
  51 #include <sys/socket.h>
  52 #include <sys/sockio.h>
  53 #include <sys/sysctl.h>
  54 #include <sys/systm.h>
  55 #include <sys/ttycom.h>
  56 #include <sys/uio.h>
  57 #include <sys/vnode.h>
  58 #include <sys/serialize.h>
  59 #include <sys/thread2.h>
  60 #include <sys/mplock2.h>
  61 #include <sys/devfs.h>
  62 #include <sys/queue.h>
  63
  64 #include <net/bpf.h>
  65 #include <net/ethernet.h>
  66 #include <net/if.h>
  67 #include <net/if_types.h>
  68 #include <net/if_arp.h>
  69 #include <net/if_clone.h>
  70 #include <net/if_media.h>
  71 #include <net/ifq_var.h>
  72 #include <net/route.h>
  73
  74 #include <netinet/in.h>
  75
  76 #include "if_tapvar.h"
  77 #include "if_tap.h"
  78
  79 #define TAP_IFFLAGS     (IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST)
  80
  81 #define TAP             "tap"
  82 #define TAPDEBUG        if (tapdebug) if_printf
  83
  84 /* module */
  85 static int              tapmodevent(module_t, int, void *);
  86
  87 /* device */
  88 static struct tap_softc *tapcreate(cdev_t, int);
  89 static void             tapdestroy(struct tap_softc *);
  90
  91 /* clone */
  92 static int              tap_clone_create(struct if_clone *, int,
  93                                          caddr_t, caddr_t);
  94 static int              tap_clone_destroy(struct ifnet *);
  95
  96 /* network interface */
  97 static void             tapifinit(void *);
  98 static void             tapifstart(struct ifnet *, struct ifaltq_subque *);
  99 static int              tapifioctl(struct ifnet *, u_long, caddr_t,
 100                                    struct ucred *);
 101 static void             tapifstop(struct tap_softc *, int);
 102 static void             tapifflags(struct tap_softc *);
 103
 104 /* character device */
 105 static d_open_t         tapopen;
 106 static d_clone_t        tapclone;
 107 static d_close_t        tapclose;
 108 static d_read_t         tapread;
 109 static d_write_t        tapwrite;
 110 static d_ioctl_t        tapioctl;
 111 static d_kqfilter_t     tapkqfilter;
 112
 113 static struct dev_ops   tap_ops = {
 114         { TAP, 0, 0 },
 115         .d_open =       tapopen,
 116         .d_close =      tapclose,
 117         .d_read =       tapread,
 118         .d_write =      tapwrite,
 119         .d_ioctl =      tapioctl,
 120         .d_kqfilter =   tapkqfilter
 121 };
 122
 123 /* kqueue support */
 124 static void             tap_filter_detach(struct knote *);
 125 static int              tap_filter_read(struct knote *, long);
 126 static int              tap_filter_write(struct knote *, long);
 127
 128 static struct filterops tapread_filtops = {
 129         FILTEROP_ISFD,
 130         NULL,
 131         tap_filter_detach,
 132         tap_filter_read
 133 };
 134 static struct filterops tapwrite_filtops = {
 135         FILTEROP_ISFD,
 136         NULL,
 137         tap_filter_detach,
 138         tap_filter_write
 139 };
 140
 141 static int              tapdebug = 0;           /* debug flag */
 142 static int              taprefcnt = 0;          /* module ref. counter */
 143 static int              tapuopen = 0;           /* allow user open() */
 144 static int              tapuponopen = 0;        /* IFF_UP when opened */
 145
 146 static MALLOC_DEFINE(M_TAP, TAP, "Ethernet tunnel interface");
 147
 148 static DEVFS_DEFINE_CLONE_BITMAP(tap);
 149
 150 struct if_clone tap_cloner = IF_CLONE_INITIALIZER(
 151         TAP, tap_clone_create, tap_clone_destroy, 0, IF_MAXUNIT);
 152
 153 static SLIST_HEAD(,tap_softc) tap_listhead =
 154         SLIST_HEAD_INITIALIZER(&tap_listhead);
 155
 156 SYSCTL_INT(_debug, OID_AUTO, if_tap_debug, CTLFLAG_RW, &tapdebug, 0, "");
 157 SYSCTL_DECL(_net_link);
 158 SYSCTL_NODE(_net_link, OID_AUTO, tap, CTLFLAG_RW, 0,
 159             "Ethernet tunnel software network interface");
 160 SYSCTL_INT(_net_link_tap, OID_AUTO, user_open, CTLFLAG_RW, &tapuopen, 0,
 161            "Allow user to open /dev/tap (based on node permissions)");
 162 SYSCTL_INT(_net_link_tap, OID_AUTO, up_on_open, CTLFLAG_RW, &tapuponopen, 0,
 163            "Bring interface up when /dev/tap is opened");
 164 SYSCTL_INT(_net_link_tap, OID_AUTO, debug, CTLFLAG_RW, &tapdebug, 0, "");
 165 SYSCTL_INT(_net_link_tap, OID_AUTO, refcnt, CTLFLAG_RD, &taprefcnt, 0,
 166            "Number of opened devices");
 167
 168 DEV_MODULE(if_tap, tapmodevent, NULL);
 169
 170 /*
 171  * tapmodevent
 172  *
 173  * module event handler
 174  */
 175 static int
 176 tapmodevent(module_t mod, int type, void *data)
 177 {
 178         static cdev_t dev = NULL;
 179         struct tap_softc *sc, *sc_tmp;
 180
 181         switch (type) {
 182         case MOD_LOAD:
 183                 dev = make_autoclone_dev(&tap_ops, &DEVFS_CLONE_BITMAP(tap),
 184                                          tapclone, UID_ROOT, GID_WHEEL,
 185                                          0600, TAP);
 186                 SLIST_INIT(&tap_listhead);
 187                 if_clone_attach(&tap_cloner);
 188                 break;
 189
 190         case MOD_UNLOAD:
 191                 if (taprefcnt > 0)
 192                         return (EBUSY);
 193
 194                 if_clone_detach(&tap_cloner);
 195
 196                 SLIST_FOREACH_MUTABLE(sc, &tap_listhead, tap_link, sc_tmp)
 197                         tapdestroy(sc);
 198
 199                 dev_ops_remove_all(&tap_ops);
 200                 destroy_autoclone_dev(dev, &DEVFS_CLONE_BITMAP(tap));
 201                 break;
 202
 203         default:
 204                 return (EOPNOTSUPP);
 205         }
 206
 207         return (0);
 208 }
 209
 210
 211 /*
 212  * Create or clone an interface
 213  */
 214 static struct tap_softc *
 215 tapcreate(cdev_t dev, int flags)
 216 {
 217         struct tap_softc *sc;
 218         struct ifnet *ifp;
 219         uint8_t ether_addr[ETHER_ADDR_LEN];
 220         int unit = minor(dev);
 221
 222         sc = kmalloc(sizeof(*sc), M_TAP, M_WAITOK | M_ZERO);
 223         dev->si_drv1 = sc;
 224         sc->tap_dev = dev;
 225         sc->tap_flags |= flags;
 226
 227         reference_dev(dev); /* device association */
 228
 229         /* generate fake MAC address: 00 bd xx xx xx unit_no */
 230         ether_addr[0] = 0x00;
 231         ether_addr[1] = 0xbd;
 232         bcopy(&ticks, &ether_addr[2], 3);
 233         ether_addr[5] = (u_char)unit;
 234
 235         /* fill the rest and attach interface */
 236         ifp = &sc->tap_if;
 237         if_initname(ifp, TAP, unit);
 238         ifp->if_type = IFT_ETHER;
 239         ifp->if_init = tapifinit;
 240         ifp->if_start = tapifstart;
 241         ifp->if_ioctl = tapifioctl;
 242         ifp->if_mtu = ETHERMTU;
 243         ifp->if_flags = TAP_IFFLAGS;
 244         ifp->if_softc = sc;
 245         ifq_set_maxlen(&ifp->if_snd, ifqmaxlen);
 246         ifq_set_ready(&ifp->if_snd);
 247
 248         ether_ifattach(ifp, ether_addr, NULL);
 249
 250         sc->tap_flags |= TAP_INITED;
 251         sc->tap_devq.ifq_maxlen = ifqmaxlen;
 252
 253         SLIST_INSERT_HEAD(&tap_listhead, sc, tap_link);
 254
 255         TAPDEBUG(ifp, "created, minor = %#x, flags = 0x%x\n",
 256                  unit, sc->tap_flags);
 257         return (sc);
 258 }
 259
 260 static struct tap_softc *
 261 tapfind(int unit)
 262 {
 263         struct tap_softc *sc;
 264
 265         SLIST_FOREACH(sc, &tap_listhead, tap_link) {
 266                 if (minor(sc->tap_dev) == unit)
 267                         return (sc);
 268         }
 269         return (NULL);
 270 }
 271
 272 /*
 273  * Create a new tap instance via ifconfig.
 274  */
 275 static int
 276 tap_clone_create(struct if_clone *ifc __unused, int unit,
 277                  caddr_t params __unused, caddr_t data)
 278 {
 279         struct tap_softc *sc;
 280         cdev_t dev = (cdev_t)data;
 281         int flags;
 282
 283         if (tapfind(unit) != NULL)
 284                 return (EEXIST);
 285
 286         if (dev == NULL) {
 287                 if (!devfs_clone_bitmap_chk(&DEVFS_CLONE_BITMAP(tap), unit)) {
 288                         devfs_clone_bitmap_set(&DEVFS_CLONE_BITMAP(tap), unit);
 289                         dev = make_dev(&tap_ops, unit, UID_ROOT, GID_WHEEL,
 290                                        0600, "%s%d", TAP, unit);
 291                 } else {
 292                         dev = devfs_find_device_by_name("%s%d", TAP, unit);
 293                         if (dev == NULL)
 294                                 return (ENOENT);
 295                 }
 296                 flags = TAP_MANUALMAKE;
 297         } else {
 298                 flags = 0;
 299         }
 300
 301         if ((sc = tapcreate(dev, flags)) == NULL)
 302                 return (ENOMEM);
 303
 304         sc->tap_flags |= TAP_CLONE;
 305
 306         TAPDEBUG(&sc->tap_if, "clone created, minor = %#x, flags = 0x%x\n",
 307                  minor(sc->tap_dev), sc->tap_flags);
 308
 309         return (0);
 310 }
 311
 312 /*
 313  * Open the tap device.
 314  */
 315 static int
 316 tapopen(struct dev_open_args *ap)
 317 {
 318         cdev_t dev = NULL;
 319         struct tap_softc *sc = NULL;
 320         struct ifnet *ifp = NULL;
 321         int error;
 322
 323         if (tapuopen == 0 &&
 324             (error = caps_priv_check(ap->a_cred, SYSCAP_RESTRICTEDROOT)) != 0)
 325         {
 326                 return (error);
 327         }
 328
 329         get_mplock();
 330
 331         dev = ap->a_head.a_dev;
 332         sc = dev->si_drv1;
 333         if (sc == NULL && (sc = tapcreate(dev, 0)) == NULL) {
 334                 rel_mplock();
 335                 return (ENOMEM);
 336         }
 337         if (sc->tap_flags & TAP_OPEN) {
 338                 rel_mplock();
 339                 return (EBUSY);
 340         }
 341
 342         ifp = &sc->tap_if;
 343         bcopy(sc->arpcom.ac_enaddr, sc->ether_addr, sizeof(sc->ether_addr));
 344
 345         if (curthread->td_proc)
 346                 fsetown(curthread->td_proc->p_pid, &sc->tap_sigtd);
 347         sc->tap_flags |= TAP_OPEN;
 348         taprefcnt++;
 349
 350         if (tapuponopen && (ifp->if_flags & IFF_UP) == 0) {
 351                 crit_enter();
 352                 if_up(ifp);
 353                 crit_exit();
 354
 355                 ifnet_serialize_all(ifp);
 356                 tapifflags(sc);
 357                 ifnet_deserialize_all(ifp);
 358
 359                 sc->tap_flags |= TAP_CLOSEDOWN;
 360         }
 361
 362         TAPDEBUG(ifp, "opened, minor = %#x. Module refcnt = %d\n",
 363                  minor(dev), taprefcnt);
 364
 365         rel_mplock();
 366         return (0);
 367 }
 368
 369 static int
 370 tapclone(struct dev_clone_args *ap)
 371 {
 372         char ifname[IFNAMSIZ];
 373         int unit;
 374
 375         unit = devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(tap), 0);
 376         ksnprintf(ifname, IFNAMSIZ, "%s%d", TAP, unit);
 377         ap->a_dev = make_only_dev(&tap_ops, unit, UID_ROOT, GID_WHEEL,
 378                                   0600, "%s", ifname);
 379
 380         /*
 381          * Use the if_clone framework to create cloned device/interface,
 382          * so the two clone methods (autoclone device /dev/tap; ifconfig
 383          * clone) are consistent and can be mix used.
 384          *
 385          * Need to pass the cdev_t because the device created by
 386          * 'make_only_dev()' doesn't appear in '/dev' yet so that it can't
 387          * be found by 'devfs_find_device_by_name()' in 'tap_clone_create()'.
 388          */
 389         return (if_clone_create(ifname, IFNAMSIZ, NULL, (caddr_t)ap->a_dev));
 390 }
 391
 392 /*
 393  * Close the tap device: bring the interface down & delete routing info.
 394  */
 395 static int
 396 tapclose(struct dev_close_args *ap)
 397 {
 398         cdev_t dev = ap->a_head.a_dev;
 399         struct tap_softc *sc = dev->si_drv1;
 400         struct ifnet *ifp;
 401         int unit = minor(dev);
 402         int clear_flags = 0;
 403         char ifname[IFNAMSIZ];
 404
 405         KASSERT(sc != NULL,
 406                 ("try closing the already destroyed %s%d", TAP, unit));
 407         ifp = &sc->tap_if;
 408
 409         get_mplock();
 410
 411         /* Junk all pending output */
 412         ifq_purge_all(&ifp->if_snd);
 413
 414         /*
 415          * If the interface is not cloned, we always bring it down.
 416          *
 417          * If the interface is cloned, then we bring it down during
 418          * closing only if it was brought up during opening.
 419          */
 420         if ((sc->tap_flags & TAP_CLONE) == 0 ||
 421             (sc->tap_flags & TAP_CLOSEDOWN)) {
 422                 if (ifp->if_flags & IFF_UP)
 423                         if_down(ifp);
 424                 clear_flags = 1;
 425         }
 426         ifnet_serialize_all(ifp);
 427         tapifstop(sc, clear_flags);
 428         ifnet_deserialize_all(ifp);
 429
 430         if ((sc->tap_flags & TAP_MANUALMAKE) == 0) {
 431                 if_purgeaddrs_nolink(ifp);
 432
 433                 EVENTHANDLER_INVOKE(ifnet_detach_event, ifp);
 434
 435                 /* Announce the departure of the interface. */
 436                 rt_ifannouncemsg(ifp, IFAN_DEPARTURE);
 437         }
 438
 439         funsetown(&sc->tap_sigio);
 440         sc->tap_sigio = NULL;
 441         KNOTE(&sc->tap_rkq.ki_note, 0);
 442
 443         sc->tap_flags &= ~TAP_OPEN;
 444         funsetown(&sc->tap_sigtd);
 445         sc->tap_sigtd = NULL;
 446
 447         taprefcnt--;
 448         if (taprefcnt < 0) {
 449                 taprefcnt = 0;
 450                 if_printf(ifp, ". Module refcnt = %d is out of sync! "
 451                           "Force refcnt to be 0.\n", taprefcnt);
 452         }
 453
 454         TAPDEBUG(ifp, "closed, minor = %#x. Module refcnt = %d\n",
 455                  unit, taprefcnt);
 456
 457         /* Only auto-destroy if the interface was not manually created. */
 458         if ((sc->tap_flags & TAP_MANUALMAKE) == 0) {
 459                 ksnprintf(ifname, IFNAMSIZ, "%s%d", TAP, unit);
 460                 if_clone_destroy(ifname);
 461         }
 462
 463         rel_mplock();
 464         return (0);
 465 }
 466
 467
 468 /*
 469  * Destroy a tap instance: the interface and the associated device.
 470  */
 471 static void
 472 tapdestroy(struct tap_softc *sc)
 473 {
 474         struct ifnet *ifp = &sc->tap_if;
 475         cdev_t dev = sc->tap_dev;
 476         int unit = minor(dev);
 477
 478         TAPDEBUG(ifp, "destroyed, minor = %#x. Module refcnt = %d\n",
 479                  unit, taprefcnt);
 480
 481         ifnet_serialize_all(ifp);
 482         tapifstop(sc, 1);
 483         ifnet_deserialize_all(ifp);
 484         ether_ifdetach(ifp);
 485
 486         sc->tap_dev = NULL;
 487         dev->si_drv1 = NULL;
 488         release_dev(dev); /* device disassociation */
 489
 490         /* Also destroy the cloned device */
 491         destroy_dev(dev);
 492         devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(tap), unit);
 493
 494         SLIST_REMOVE(&tap_listhead, sc, tap_softc, tap_link);
 495         kfree(sc, M_TAP);
 496 }
 497
 498
 499 /*
 500  * Destroy a tap instance that is created via ifconfig.
 501  */
 502 static int
 503 tap_clone_destroy(struct ifnet *ifp)
 504 {
 505         struct tap_softc *sc = ifp->if_softc;
 506
 507         if (sc->tap_flags & TAP_OPEN)
 508                 return (EBUSY);
 509         if ((sc->tap_flags & TAP_CLONE) == 0)
 510                 return (EINVAL);
 511
 512         TAPDEBUG(ifp, "clone destroyed, minor = %#x, flags = 0x%x\n",
 513                  minor(sc->tap_dev), sc->tap_flags);
 514         tapdestroy(sc);
 515
 516         return (0);
 517 }
 518
 519
 520 /*
 521  * tapifinit
 522  *
 523  * Network interface initialization function (called with if serializer held)
 524  *
 525  * MPSAFE
 526  */
 527 static void
 528 tapifinit(void *xtp)
 529 {
 530         struct tap_softc *sc = xtp;
 531         struct ifnet *ifp = &sc->tap_if;
 532         struct ifaltq_subque *ifsq = ifq_get_subq_default(&ifp->if_snd);
 533
 534         TAPDEBUG(ifp, "initializing, minor = %#x, flags = 0x%x\n",
 535                  minor(sc->tap_dev), sc->tap_flags);
 536
 537         ASSERT_IFNET_SERIALIZED_ALL(ifp);
 538
 539         tapifstop(sc, 1);
 540
 541         ifp->if_flags |= IFF_RUNNING;
 542         ifsq_clr_oactive(ifsq);
 543
 544         /* attempt to start output */
 545         tapifstart(ifp, ifsq);
 546 }
 547
 548 static void
 549 tapifflags(struct tap_softc *sc)
 550 {
 551         struct ifnet *ifp = &sc->tap_if;
 552
 553         ASSERT_IFNET_SERIALIZED_ALL(ifp);
 554
 555         if (ifp->if_flags & IFF_UP) {
 556                 if ((ifp->if_flags & IFF_RUNNING) == 0)
 557                         tapifinit(sc);
 558         } else {
 559                 tapifstop(sc, 1);
 560         }
 561 }
 562
 563 /*
 564  * tapifioctl
 565  *
 566  * Process an ioctl request on network interface (called with if serializer
 567  * held).
 568  *
 569  * MPSAFE
 570  */
 571 static int
 572 tapifioctl(struct ifnet *ifp, u_long cmd, caddr_t data, struct ucred *cr)
 573 {
 574         struct tap_softc *sc = ifp->if_softc;
 575         struct ifreq *ifr = NULL;
 576         struct ifstat *ifs = NULL;
 577         struct ifmediareq *ifmr = NULL;
 578         int error = 0;
 579         int dummy;
 580
 581         switch (cmd) {
 582         case SIOCADDMULTI:
 583         case SIOCDELMULTI:
 584                 break;
 585
 586         case SIOCSIFMTU:
 587                 ifr = (struct ifreq *)data;
 588                 ifp->if_mtu = ifr->ifr_mtu;
 589                 TAPDEBUG(ifp, "mtu set\n");
 590                 break;
 591
 592         case SIOCSIFADDR:
 593         case SIOCGIFADDR:
 594                 error = ether_ioctl(ifp, cmd, data);
 595                 break;
 596
 597         case SIOCSIFFLAGS:
 598                 tapifflags(sc);
 599                 break;
 600
 601         case SIOCGIFMEDIA:
 602                 /*
 603                  * The bridge code needs this when running the
 604                  * spanning tree protocol.
 605                  */
 606                 ifmr = (struct ifmediareq *)data;
 607                 dummy = ifmr->ifm_count;
 608                 ifmr->ifm_count = 1;
 609                 ifmr->ifm_status = IFM_AVALID;
 610                 ifmr->ifm_active = IFM_ETHER;
 611                 if (sc->tap_flags & TAP_OPEN)
 612                         ifmr->ifm_status |= IFM_ACTIVE;
 613                 ifmr->ifm_current = ifmr->ifm_active;
 614                 if (dummy >= 1) {
 615                         int media = IFM_ETHER;
 616                         error = copyout(&media, ifmr->ifm_ulist, sizeof(int));
 617                 }
 618                 break;
 619
 620         case SIOCGIFSTATUS:
 621                 ifs = (struct ifstat *)data;
 622                 dummy = strlen(ifs->ascii);
 623                 if ((sc->tap_flags & TAP_OPEN) && dummy < sizeof(ifs->ascii)) {
 624                         if (sc->tap_sigtd && sc->tap_sigtd->sio_proc) {
 625                                 ksnprintf(ifs->ascii + dummy,
 626                                     sizeof(ifs->ascii) - dummy,
 627                                     "\tOpened by pid %d\n",
 628                                     (int)sc->tap_sigtd->sio_proc->p_pid);
 629                         } else {
 630                                 ksnprintf(ifs->ascii + dummy,
 631                                     sizeof(ifs->ascii) - dummy,
 632                                     "\tOpened by <unknown>\n");
 633                         }
 634                 }
 635                 break;
 636
 637         default:
 638                 error = EINVAL;
 639                 break;
 640         }
 641
 642         return (error);
 643 }
 644
 645 /*
 646  * tapifstart
 647  *
 648  * Queue packets from higher level ready to put out (called with if serializer
 649  * held)
 650  *
 651  * MPSAFE
 652  */
 653 static void
 654 tapifstart(struct ifnet *ifp, struct ifaltq_subque *ifsq)
 655 {
 656         struct tap_softc *sc = ifp->if_softc;
 657         struct ifqueue *ifq;
 658         struct mbuf *m;
 659         int has_data = 0;
 660
 661         ASSERT_ALTQ_SQ_DEFAULT(ifp, ifsq);
 662         TAPDEBUG(ifp, "starting, minor = %#x\n", minor(sc->tap_dev));
 663
 664         if ((sc->tap_flags & TAP_READY) != TAP_READY) {
 665                 TAPDEBUG(ifp, "not ready, minor = %#x, flags = 0x%x\n",
 666                          minor(sc->tap_dev), sc->tap_flags);
 667                 ifsq_purge(ifsq);
 668                 return;
 669         }
 670
 671         ifsq_set_oactive(ifsq);
 672
 673         ifq = &sc->tap_devq;
 674         while ((m = ifsq_dequeue(ifsq)) != NULL) {
 675                 if (IF_QFULL(ifq)) {
 676                         IF_DROP(ifq);
 677                         IFNET_STAT_INC(ifp, oerrors, 1);
 678                         m_freem(m);
 679                 } else {
 680                         IF_ENQUEUE(ifq, m);
 681                         IFNET_STAT_INC(ifp, opackets, 1);
 682                         has_data = 1;
 683                 }
 684         }
 685
 686         if (has_data) {
 687                 if (sc->tap_flags & TAP_RWAIT) {
 688                         sc->tap_flags &= ~TAP_RWAIT;
 689                         wakeup((caddr_t)sc);
 690                 }
 691
 692                 KNOTE(&sc->tap_rkq.ki_note, 0);
 693
 694                 if ((sc->tap_flags & TAP_ASYNC) && (sc->tap_sigio != NULL)) {
 695                         get_mplock();
 696                         pgsigio(sc->tap_sigio, SIGIO, 0);
 697                         rel_mplock();
 698                 }
 699         }
 700
 701         ifsq_clr_oactive(ifsq);
 702 }
 703
 704 static void
 705 tapifstop(struct tap_softc *sc, int clear_flags)
 706 {
 707         struct ifnet *ifp = &sc->tap_if;
 708
 709         ASSERT_IFNET_SERIALIZED_ALL(ifp);
 710         IF_DRAIN(&sc->tap_devq);
 711         sc->tap_flags &= ~TAP_CLOSEDOWN;
 712         if (clear_flags) {
 713                 ifp->if_flags &= ~IFF_RUNNING;
 714                 ifsq_clr_oactive(ifq_get_subq_default(&ifp->if_snd));
 715         }
 716 }
 717
 718 /*
 719  * tapioctl
 720  *
 721  * The ops interface is now pretty minimal.  Called via fileops with nothing
 722  * held.
 723  *
 724  * MPSAFE
 725  */
 726 static int
 727 tapioctl(struct dev_ioctl_args *ap)
 728 {
 729         cdev_t dev = ap->a_head.a_dev;
 730         caddr_t data = ap->a_data;
 731         struct tap_softc *sc = dev->si_drv1;
 732         struct ifnet *ifp = &sc->tap_if;
 733         struct ifreq *ifr;
 734         struct tapinfo *tapp = NULL;
 735         struct mbuf *mb;
 736         int error;
 737
 738         ifnet_serialize_all(ifp);
 739         error = 0;
 740
 741         switch (ap->a_cmd) {
 742         case TAPSIFINFO:
 743                 tapp = (struct tapinfo *)data;
 744                 if (ifp->if_type != tapp->type)
 745                         return (EPROTOTYPE);
 746                 ifp->if_mtu = tapp->mtu;
 747                 ifp->if_baudrate = tapp->baudrate;
 748                 break;
 749
 750         case TAPGIFINFO:
 751                 tapp = (struct tapinfo *)data;
 752                 tapp->mtu = ifp->if_mtu;
 753                 tapp->type = ifp->if_type;
 754                 tapp->baudrate = ifp->if_baudrate;
 755                 break;
 756
 757         case TAPGIFNAME:
 758                 ifr = (struct ifreq *)data;
 759                 strlcpy(ifr->ifr_name, ifp->if_xname, IFNAMSIZ);
 760                 break;
 761
 762         case TAPSDEBUG:
 763                 tapdebug = *(int *)data;
 764                 break;
 765
 766         case TAPGDEBUG:
 767                 *(int *)data = tapdebug;
 768                 break;
 769
 770         case FIOASYNC:
 771                 if (*(int *)data)
 772                         sc->tap_flags |= TAP_ASYNC;
 773                 else
 774                         sc->tap_flags &= ~TAP_ASYNC;
 775                 break;
 776
 777         case FIONREAD:
 778                 /* Take a look at devq first */
 779                 IF_POLL(&sc->tap_devq, mb);
 780                 if (mb != NULL) {
 781                         *(int *)data = 0;
 782                         for(; mb != NULL; mb = mb->m_next)
 783                                 *(int *)data += mb->m_len;
 784                 } else {
 785                         *(int *)data = ifsq_poll_pktlen(
 786                             ifq_get_subq_default(&ifp->if_snd));
 787                 }
 788                 break;
 789
 790         case FIOSETOWN:
 791                 error = fsetown(*(int *)data, &sc->tap_sigio);
 792                 if (error == 0)
 793                         error = fsetown(*(int *)data, &sc->tap_sigtd);
 794                 break;
 795
 796         case FIOGETOWN:
 797                 *(int *)data = fgetown(&sc->tap_sigio);
 798                 break;
 799
 800         /* this is deprecated, FIOSETOWN should be used instead */
 801         case TIOCSPGRP:
 802                 error = fsetown(-(*(int *)data), &sc->tap_sigio);
 803                 break;
 804
 805         /* this is deprecated, FIOGETOWN should be used instead */
 806         case TIOCGPGRP:
 807                 *(int *)data = -fgetown(&sc->tap_sigio);
 808                 break;
 809
 810         /*
 811          * Support basic control of the network interface via the device file.
 812          * e.g., vke(4) currently uses the 'SIOCGIFADDR' ioctl.
 813          */
 814
 815         case SIOCGIFFLAGS:
 816                 bcopy(&ifp->if_flags, data, sizeof(ifp->if_flags));
 817                 break;
 818
 819         case SIOCGIFADDR:
 820                 bcopy(sc->ether_addr, data, sizeof(sc->ether_addr));
 821                 break;
 822
 823         case SIOCSIFADDR:
 824                 bcopy(data, sc->ether_addr, sizeof(sc->ether_addr));
 825                 break;
 826
 827         default:
 828                 error = ENOTTY;
 829                 break;
 830         }
 831
 832         ifnet_deserialize_all(ifp);
 833         return (error);
 834 }
 835
 836
 837 /*
 838  * tapread
 839  *
 840  * The ops read interface - reads a packet at a time, or at
 841  * least as much of a packet as can be read.
 842  *
 843  * Called from the fileops interface with nothing held.
 844  *
 845  * MPSAFE
 846  */
 847 static int
 848 tapread(struct dev_read_args *ap)
 849 {
 850         cdev_t dev = ap->a_head.a_dev;
 851         struct uio *uio = ap->a_uio;
 852         struct tap_softc *sc = dev->si_drv1;
 853         struct ifnet *ifp = &sc->tap_if;
 854         struct mbuf *m0 = NULL;
 855         int error = 0, len;
 856
 857         TAPDEBUG(ifp, "reading, minor = %#x\n", minor(dev));
 858
 859         if ((sc->tap_flags & TAP_READY) != TAP_READY) {
 860                 TAPDEBUG(ifp, "not ready, minor = %#x, flags = 0x%x\n",
 861                          minor(dev), sc->tap_flags);
 862
 863                 return (EHOSTDOWN);
 864         }
 865
 866         sc->tap_flags &= ~TAP_RWAIT;
 867
 868         /* sleep until we get a packet */
 869         do {
 870                 ifnet_serialize_all(ifp);
 871                 IF_DEQUEUE(&sc->tap_devq, m0);
 872                 if (m0 == NULL) {
 873                         if (ap->a_ioflag & IO_NDELAY) {
 874                                 ifnet_deserialize_all(ifp);
 875                                 return (EWOULDBLOCK);
 876                         }
 877                         sc->tap_flags |= TAP_RWAIT;
 878                         tsleep_interlock(sc, PCATCH);
 879                         ifnet_deserialize_all(ifp);
 880                         error = tsleep(sc, PCATCH | PINTERLOCKED, "taprd", 0);
 881                         if (error)
 882                                 return (error);
 883                 } else {
 884                         ifnet_deserialize_all(ifp);
 885                 }
 886         } while (m0 == NULL);
 887
 888         BPF_MTAP(ifp, m0);
 889
 890         /* xfer packet to user space */
 891         while ((m0 != NULL) && (uio->uio_resid > 0) && (error == 0)) {
 892                 len = (int)szmin(uio->uio_resid, m0->m_len);
 893                 if (len == 0)
 894                         break;
 895
 896                 error = uiomove(mtod(m0, caddr_t), (size_t)len, uio);
 897                 m0 = m_free(m0);
 898         }
 899
 900         if (m0 != NULL) {
 901                 TAPDEBUG(ifp, "dropping mbuf, minor = %#x\n", minor(dev));
 902                 m_freem(m0);
 903         }
 904
 905         return (error);
 906 }
 907
 908 /*
 909  * tapwrite
 910  *
 911  * The ops write interface - an atomic write is a packet - or else!
 912  *
 913  * Called from the fileops interface with nothing held.
 914  *
 915  * MPSAFE
 916  */
 917 static int
 918 tapwrite(struct dev_write_args *ap)
 919 {
 920         cdev_t dev = ap->a_head.a_dev;
 921         struct uio *uio = ap->a_uio;
 922         struct tap_softc *sc = dev->si_drv1;
 923         struct ifnet *ifp = &sc->tap_if;
 924         struct mbuf *top = NULL, **mp = NULL, *m = NULL;
 925         int error;
 926         size_t tlen, mlen;
 927
 928         TAPDEBUG(ifp, "writing, minor = %#x\n", minor(dev));
 929
 930         if ((sc->tap_flags & TAP_READY) != TAP_READY) {
 931                 TAPDEBUG(ifp, "not ready, minor = %#x, flags = 0x%x\n",
 932                          minor(dev), sc->tap_flags);
 933                 return (EHOSTDOWN);
 934         }
 935
 936         if (uio->uio_resid == 0)
 937                 return (0);
 938
 939         if (uio->uio_resid > TAPMRU) {
 940                 TAPDEBUG(ifp, "invalid packet len = %zu, minor = %#x\n",
 941                          uio->uio_resid, minor(dev));
 942
 943                 return (EIO);
 944         }
 945         tlen = uio->uio_resid;
 946
 947         /* get a header mbuf */
 948         MGETHDR(m, M_WAITOK, MT_DATA);
 949         mlen = MHLEN;
 950
 951         top = NULL;
 952         mp = &top;
 953         error = 0;
 954
 955         while (error == 0 && uio->uio_resid > 0) {
 956                 m->m_len = (int)szmin(mlen, uio->uio_resid);
 957                 error = uiomove(mtod(m, caddr_t), (size_t)m->m_len, uio);
 958                 *mp = m;
 959                 mp = &m->m_next;
 960                 if (uio->uio_resid > 0) {
 961                         MGET(m, M_WAITOK, MT_DATA);
 962                         mlen = MLEN;
 963                 }
 964         }
 965         if (error) {
 966                 IFNET_STAT_INC(ifp, ierrors, 1);
 967                 if (top)
 968                         m_freem(top);
 969                 return (error);
 970         }
 971
 972         top->m_pkthdr.len = (int)tlen;
 973         top->m_pkthdr.rcvif = ifp;
 974
 975         /*
 976          * Ethernet bridge and bpf are handled in ether_input
 977          *
 978          * adjust mbuf and give packet to the ether_input
 979          */
 980         ifnet_serialize_all(ifp);
 981         ifp->if_input(ifp, top, NULL, -1);
 982         IFNET_STAT_INC(ifp, ipackets, 1); /* ibytes are counted in ether_input */
 983         ifnet_deserialize_all(ifp);
 984
 985         return (0);
 986 }
 987
 988
 989 /*
 990  * tapkqfilter - called from the fileops interface with nothing held
 991  *
 992  * MPSAFE
 993  */
 994 static int
 995 tapkqfilter(struct dev_kqfilter_args *ap)
 996 {
 997         cdev_t dev = ap->a_head.a_dev;
 998         struct knote *kn = ap->a_kn;
 999         struct tap_softc *sc = dev->si_drv1;
1000         struct klist *list;
1001
1002         list = &sc->tap_rkq.ki_note;
1003         ap->a_result =0;
1004
1005         switch (kn->kn_filter) {
1006         case EVFILT_READ:
1007                 kn->kn_fop = &tapread_filtops;
1008                 kn->kn_hook = (void *)sc;
1009                 break;
1010         case EVFILT_WRITE:
1011                 kn->kn_fop = &tapwrite_filtops;
1012                 kn->kn_hook = (void *)sc;
1013                 break;
1014         default:
1015                 ap->a_result = EOPNOTSUPP;
1016                 return (0);
1017         }
1018
1019         knote_insert(list, kn);
1020         return (0);
1021 }
1022
1023 static int
1024 tap_filter_read(struct knote *kn, long hint)
1025 {
1026         struct tap_softc *sc = (struct tap_softc *)kn->kn_hook;
1027
1028         if (IF_QEMPTY(&sc->tap_devq) == 0)      /* XXX serializer */
1029                 return (1);
1030         else
1031                 return (0);
1032 }
1033
1034 static int
1035 tap_filter_write(struct knote *kn, long hint)
1036 {
1037         /* Always ready for a write */
1038         return (1);
1039 }
1040
1041 static void
1042 tap_filter_detach(struct knote *kn)
1043 {
1044         struct tap_softc *sc = (struct tap_softc *)kn->kn_hook;
1045
1046         knote_remove(&sc->tap_rkq.ki_note, kn);
1047 }