1 /* $NetBSD: if_tun.c,v 1.14 1994/06/29 06:36:25 cgd Exp $ */ 2 /*- 3 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 4 * 5 * Copyright (C) 1999-2000 by Maksim Yevmenkin <m_evmenkin@yahoo.com> 6 * All rights reserved. 7 * Copyright (c) 2019 Kyle Evans <kevans@FreeBSD.org> 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * BASED ON: 32 * ------------------------------------------------------------------------- 33 * 34 * Copyright (c) 1988, Julian Onions <jpo@cs.nott.ac.uk> 35 * Nottingham University 1987. 36 * 37 * This source may be freely distributed, however I would be interested 38 * in any changes that are made. 39 * 40 * This driver takes packets off the IP i/f and hands them up to a 41 * user process to have its wicked way with. This driver has it's 42 * roots in a similar driver written by Phil Cockcroft (formerly) at 43 * UCL. This driver is based much more on read/write/poll mode of 44 * operation though. 45 * 46 * $FreeBSD$ 47 */ 48 49 #include "opt_inet.h" 50 #include "opt_inet6.h" 51 52 #include <sys/param.h> 53 #include <sys/lock.h> 54 #include <sys/priv.h> 55 #include <sys/proc.h> 56 #include <sys/systm.h> 57 #include <sys/jail.h> 58 #include <sys/mbuf.h> 59 #include <sys/module.h> 60 #include <sys/socket.h> 61 #include <sys/eventhandler.h> 62 #include <sys/fcntl.h> 63 #include <sys/filio.h> 64 #include <sys/sockio.h> 65 #include <sys/sx.h> 66 #include <sys/ttycom.h> 67 #include <sys/poll.h> 68 #include <sys/selinfo.h> 69 #include <sys/signalvar.h> 70 #include <sys/filedesc.h> 71 #include <sys/kernel.h> 72 #include <sys/sysctl.h> 73 #include <sys/conf.h> 74 #include <sys/uio.h> 75 #include <sys/malloc.h> 76 #include <sys/random.h> 77 #include <sys/ctype.h> 78 79 #include <net/ethernet.h> 80 #include <net/if.h> 81 #include <net/if_var.h> 82 #include <net/if_clone.h> 83 #include <net/if_dl.h> 84 #include <net/if_media.h> 85 #include <net/if_types.h> 86 #include <net/netisr.h> 87 #include <net/route.h> 88 #include <net/vnet.h> 89 #ifdef INET 90 #include <netinet/in.h> 91 #endif 92 #include <net/bpf.h> 93 #include <net/if_tap.h> 94 #include <net/if_tun.h> 95 96 #include <sys/queue.h> 97 #include <sys/condvar.h> 98 #include <security/mac/mac_framework.h> 99 100 struct tuntap_driver; 101 102 /* 103 * tun_list is protected by global tunmtx. Other mutable fields are 104 * protected by tun->tun_mtx, or by their owning subsystem. tun_dev is 105 * static for the duration of a tunnel interface. 106 */ 107 struct tuntap_softc { 108 TAILQ_ENTRY(tuntap_softc) tun_list; 109 struct cdev *tun_dev; 110 u_short tun_flags; /* misc flags */ 111 #define TUN_OPEN 0x0001 112 #define TUN_INITED 0x0002 113 #define TUN_RCOLL 0x0004 114 #define TUN_IASET 0x0008 115 #define TUN_DSTADDR 0x0010 116 #define TUN_LMODE 0x0020 117 #define TUN_RWAIT 0x0040 118 #define TUN_ASYNC 0x0080 119 #define TUN_IFHEAD 0x0100 120 #define TUN_DYING 0x0200 121 #define TUN_L2 0x0400 122 #define TUN_VMNET 0x0800 123 124 #define TUN_DRIVER_IDENT_MASK (TUN_L2 | TUN_VMNET) 125 #define TUN_READY (TUN_OPEN | TUN_INITED) 126 127 pid_t tun_pid; /* owning pid */ 128 struct ifnet *tun_ifp; /* the interface */ 129 struct sigio *tun_sigio; /* async I/O info */ 130 struct tuntap_driver *tun_drv; /* appropriate driver */ 131 struct selinfo tun_rsel; /* read select */ 132 struct mtx tun_mtx; /* softc field mutex */ 133 struct cv tun_cv; /* for ref'd dev destroy */ 134 struct ether_addr tun_ether; /* remote address */ 135 }; 136 #define TUN2IFP(sc) ((sc)->tun_ifp) 137 138 #define TUNDEBUG if (tundebug) if_printf 139 140 #define TUN_LOCK(tp) mtx_lock(&(tp)->tun_mtx) 141 #define TUN_UNLOCK(tp) mtx_unlock(&(tp)->tun_mtx) 142 143 #define TUN_VMIO_FLAG_MASK 0x0fff 144 145 /* 146 * All mutable global variables in if_tun are locked using tunmtx, with 147 * the exception of tundebug, which is used unlocked, and the drivers' *clones, 148 * which are static after setup. 149 */ 150 static struct mtx tunmtx; 151 static eventhandler_tag tag; 152 static const char tunname[] = "tun"; 153 static const char tapname[] = "tap"; 154 static const char vmnetname[] = "vmnet"; 155 static MALLOC_DEFINE(M_TUN, tunname, "Tunnel Interface"); 156 static int tundebug = 0; 157 static int tundclone = 1; 158 static int tap_allow_uopen = 0; /* allow user open() */ 159 static int tapuponopen = 0; /* IFF_UP on open() */ 160 static int tapdclone = 1; /* enable devfs cloning */ 161 162 static TAILQ_HEAD(,tuntap_softc) tunhead = TAILQ_HEAD_INITIALIZER(tunhead); 163 SYSCTL_INT(_debug, OID_AUTO, if_tun_debug, CTLFLAG_RW, &tundebug, 0, ""); 164 165 static struct sx tun_ioctl_sx; 166 SX_SYSINIT(tun_ioctl_sx, &tun_ioctl_sx, "tun_ioctl"); 167 168 SYSCTL_DECL(_net_link); 169 /* tun */ 170 static SYSCTL_NODE(_net_link, OID_AUTO, tun, CTLFLAG_RW, 0, 171 "IP tunnel software network interface."); 172 SYSCTL_INT(_net_link_tun, OID_AUTO, devfs_cloning, CTLFLAG_RWTUN, &tundclone, 0, 173 "Enable legacy devfs interface creation."); 174 175 /* tap */ 176 static SYSCTL_NODE(_net_link, OID_AUTO, tap, CTLFLAG_RW, 0, 177 "Ethernet tunnel software network interface"); 178 SYSCTL_INT(_net_link_tap, OID_AUTO, user_open, CTLFLAG_RW, &tap_allow_uopen, 0, 179 "Allow user to open /dev/tap (based on node permissions)"); 180 SYSCTL_INT(_net_link_tap, OID_AUTO, up_on_open, CTLFLAG_RW, &tapuponopen, 0, 181 "Bring interface up when /dev/tap is opened"); 182 SYSCTL_INT(_net_link_tap, OID_AUTO, devfs_cloning, CTLFLAG_RWTUN, &tapdclone, 0, 183 "Enable legacy devfs interface creation"); 184 SYSCTL_INT(_net_link_tap, OID_AUTO, debug, CTLFLAG_RW, &tundebug, 0, ""); 185 186 static int tuntap_name2info(const char *name, int *unit, int *flags); 187 static void tunclone(void *arg, struct ucred *cred, char *name, 188 int namelen, struct cdev **dev); 189 static void tuncreate(struct cdev *dev, struct tuntap_driver *); 190 static int tunifioctl(struct ifnet *, u_long, caddr_t); 191 static void tuninit(struct ifnet *); 192 static void tunifinit(void *xtp); 193 static int tuntapmodevent(module_t, int, void *); 194 static int tunoutput(struct ifnet *, struct mbuf *, 195 const struct sockaddr *, struct route *ro); 196 static void tunstart(struct ifnet *); 197 static void tunstart_l2(struct ifnet *); 198 199 static int tun_clone_match(struct if_clone *ifc, const char *name); 200 static int tap_clone_match(struct if_clone *ifc, const char *name); 201 static int vmnet_clone_match(struct if_clone *ifc, const char *name); 202 static int tun_clone_create(struct if_clone *, char *, size_t, caddr_t); 203 static int tun_clone_destroy(struct if_clone *, struct ifnet *); 204 205 static d_open_t tunopen; 206 static d_close_t tunclose; 207 static d_read_t tunread; 208 static d_write_t tunwrite; 209 static d_ioctl_t tunioctl; 210 static d_poll_t tunpoll; 211 static d_kqfilter_t tunkqfilter; 212 213 static int tunkqread(struct knote *, long); 214 static int tunkqwrite(struct knote *, long); 215 static void tunkqdetach(struct knote *); 216 217 static struct filterops tun_read_filterops = { 218 .f_isfd = 1, 219 .f_attach = NULL, 220 .f_detach = tunkqdetach, 221 .f_event = tunkqread, 222 }; 223 224 static struct filterops tun_write_filterops = { 225 .f_isfd = 1, 226 .f_attach = NULL, 227 .f_detach = tunkqdetach, 228 .f_event = tunkqwrite, 229 }; 230 231 static struct tuntap_driver { 232 struct cdevsw cdevsw; 233 int ident_flags; 234 struct unrhdr *unrhdr; 235 struct clonedevs *clones; 236 ifc_match_t *clone_match_fn; 237 ifc_create_t *clone_create_fn; 238 ifc_destroy_t *clone_destroy_fn; 239 } tuntap_drivers[] = { 240 { 241 .ident_flags = 0, 242 .cdevsw = { 243 .d_version = D_VERSION, 244 .d_flags = D_NEEDMINOR, 245 .d_open = tunopen, 246 .d_close = tunclose, 247 .d_read = tunread, 248 .d_write = tunwrite, 249 .d_ioctl = tunioctl, 250 .d_poll = tunpoll, 251 .d_kqfilter = tunkqfilter, 252 .d_name = tunname, 253 }, 254 .clone_match_fn = tun_clone_match, 255 .clone_create_fn = tun_clone_create, 256 .clone_destroy_fn = tun_clone_destroy, 257 }, 258 { 259 .ident_flags = TUN_L2, 260 .cdevsw = { 261 .d_version = D_VERSION, 262 .d_flags = D_NEEDMINOR, 263 .d_open = tunopen, 264 .d_close = tunclose, 265 .d_read = tunread, 266 .d_write = tunwrite, 267 .d_ioctl = tunioctl, 268 .d_poll = tunpoll, 269 .d_kqfilter = tunkqfilter, 270 .d_name = tapname, 271 }, 272 .clone_match_fn = tap_clone_match, 273 .clone_create_fn = tun_clone_create, 274 .clone_destroy_fn = tun_clone_destroy, 275 }, 276 { 277 .ident_flags = TUN_L2 | TUN_VMNET, 278 .cdevsw = { 279 .d_version = D_VERSION, 280 .d_flags = D_NEEDMINOR, 281 .d_open = tunopen, 282 .d_close = tunclose, 283 .d_read = tunread, 284 .d_write = tunwrite, 285 .d_ioctl = tunioctl, 286 .d_poll = tunpoll, 287 .d_kqfilter = tunkqfilter, 288 .d_name = vmnetname, 289 }, 290 .clone_match_fn = vmnet_clone_match, 291 .clone_create_fn = tun_clone_create, 292 .clone_destroy_fn = tun_clone_destroy, 293 }, 294 }; 295 296 struct tuntap_driver_cloner { 297 SLIST_ENTRY(tuntap_driver_cloner) link; 298 struct tuntap_driver *drv; 299 struct if_clone *cloner; 300 }; 301 302 VNET_DEFINE_STATIC(SLIST_HEAD(, tuntap_driver_cloner), tuntap_driver_cloners) = 303 SLIST_HEAD_INITIALIZER(tuntap_driver_cloners); 304 305 #define V_tuntap_driver_cloners VNET(tuntap_driver_cloners) 306 307 /* 308 * Sets unit and/or flags given the device name. Must be called with correct 309 * vnet context. 310 */ 311 static int 312 tuntap_name2info(const char *name, int *outunit, int *outflags) 313 { 314 struct tuntap_driver *drv; 315 struct tuntap_driver_cloner *drvc; 316 char *dname; 317 int flags, unit; 318 bool found; 319 320 if (name == NULL) 321 return (EINVAL); 322 323 /* 324 * Needed for dev_stdclone, but dev_stdclone will not modify, it just 325 * wants to be able to pass back a char * through the second param. We 326 * will always set that as NULL here, so we'll fake it. 327 */ 328 dname = __DECONST(char *, name); 329 found = false; 330 331 KASSERT(!SLIST_EMPTY(&V_tuntap_driver_cloners), 332 ("tuntap_driver_cloners failed to initialize")); 333 SLIST_FOREACH(drvc, &V_tuntap_driver_cloners, link) { 334 KASSERT(drvc->drv != NULL, 335 ("tuntap_driver_cloners entry not properly initialized")); 336 drv = drvc->drv; 337 338 if (strcmp(name, drv->cdevsw.d_name) == 0) { 339 found = true; 340 unit = -1; 341 flags = drv->ident_flags; 342 break; 343 } 344 345 if (dev_stdclone(dname, NULL, drv->cdevsw.d_name, &unit) == 1) { 346 found = true; 347 flags = drv->ident_flags; 348 break; 349 } 350 } 351 352 if (!found) 353 return (ENXIO); 354 355 if (outunit != NULL) 356 *outunit = unit; 357 if (outflags != NULL) 358 *outflags = flags; 359 return (0); 360 } 361 362 /* 363 * Get driver information from a set of flags specified. Masks the identifying 364 * part of the flags and compares it against all of the available 365 * tuntap_drivers. Must be called with correct vnet context. 366 */ 367 static struct tuntap_driver * 368 tuntap_driver_from_flags(int tun_flags) 369 { 370 struct tuntap_driver *drv; 371 struct tuntap_driver_cloner *drvc; 372 373 KASSERT(!SLIST_EMPTY(&V_tuntap_driver_cloners), 374 ("tuntap_driver_cloners failed to initialize")); 375 SLIST_FOREACH(drvc, &V_tuntap_driver_cloners, link) { 376 KASSERT(drvc->drv != NULL, 377 ("tuntap_driver_cloners entry not properly initialized")); 378 drv = drvc->drv; 379 if ((tun_flags & TUN_DRIVER_IDENT_MASK) == drv->ident_flags) 380 return (drv); 381 } 382 383 return (NULL); 384 } 385 386 387 388 static int 389 tun_clone_match(struct if_clone *ifc, const char *name) 390 { 391 int tunflags; 392 393 if (tuntap_name2info(name, NULL, &tunflags) == 0) { 394 if ((tunflags & TUN_L2) == 0) 395 return (1); 396 } 397 398 return (0); 399 } 400 401 static int 402 tap_clone_match(struct if_clone *ifc, const char *name) 403 { 404 int tunflags; 405 406 if (tuntap_name2info(name, NULL, &tunflags) == 0) { 407 if ((tunflags & (TUN_L2 | TUN_VMNET)) == TUN_L2) 408 return (1); 409 } 410 411 return (0); 412 } 413 414 static int 415 vmnet_clone_match(struct if_clone *ifc, const char *name) 416 { 417 int tunflags; 418 419 if (tuntap_name2info(name, NULL, &tunflags) == 0) { 420 if ((tunflags & TUN_VMNET) != 0) 421 return (1); 422 } 423 424 return (0); 425 } 426 427 static int 428 tun_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params) 429 { 430 struct tuntap_driver *drv; 431 struct cdev *dev; 432 int err, i, tunflags, unit; 433 434 tunflags = 0; 435 /* The name here tells us exactly what we're creating */ 436 err = tuntap_name2info(name, &unit, &tunflags); 437 if (err != 0) 438 return (err); 439 440 drv = tuntap_driver_from_flags(tunflags); 441 if (drv == NULL) 442 return (ENXIO); 443 444 if (unit != -1) { 445 /* If this unit number is still available that/s okay. */ 446 if (alloc_unr_specific(drv->unrhdr, unit) == -1) 447 return (EEXIST); 448 } else { 449 unit = alloc_unr(drv->unrhdr); 450 } 451 452 snprintf(name, IFNAMSIZ, "%s%d", drv->cdevsw.d_name, unit); 453 454 /* find any existing device, or allocate new unit number */ 455 i = clone_create(&drv->clones, &drv->cdevsw, &unit, &dev, 0); 456 if (i) { 457 /* No preexisting struct cdev *, create one */ 458 dev = make_dev(&drv->cdevsw, unit, UID_UUCP, GID_DIALER, 0600, 459 "%s%d", drv->cdevsw.d_name, unit); 460 } 461 462 tuncreate(dev, drv); 463 464 return (0); 465 } 466 467 static void 468 tunclone(void *arg, struct ucred *cred, char *name, int namelen, 469 struct cdev **dev) 470 { 471 char devname[SPECNAMELEN + 1]; 472 struct tuntap_driver *drv; 473 int append_unit, i, u, tunflags; 474 bool mayclone; 475 476 if (*dev != NULL) 477 return; 478 479 tunflags = 0; 480 CURVNET_SET(CRED_TO_VNET(cred)); 481 if (tuntap_name2info(name, &u, &tunflags) != 0) 482 goto out; /* Not recognized */ 483 484 if (u != -1 && u > IF_MAXUNIT) 485 goto out; /* Unit number too high */ 486 487 mayclone = priv_check_cred(cred, PRIV_NET_IFCREATE) == 0; 488 if ((tunflags & TUN_L2) != 0) { 489 /* tap/vmnet allow user open with a sysctl */ 490 mayclone = (mayclone || tap_allow_uopen) && tapdclone; 491 } else { 492 mayclone = mayclone && tundclone; 493 } 494 495 /* 496 * If tun cloning is enabled, only the superuser can create an 497 * interface. 498 */ 499 if (!mayclone) 500 goto out; 501 502 if (u == -1) 503 append_unit = 1; 504 else 505 append_unit = 0; 506 507 drv = tuntap_driver_from_flags(tunflags); 508 if (drv == NULL) 509 goto out; 510 511 /* find any existing device, or allocate new unit number */ 512 i = clone_create(&drv->clones, &drv->cdevsw, &u, dev, 0); 513 if (i) { 514 if (append_unit) { 515 namelen = snprintf(devname, sizeof(devname), "%s%d", 516 name, u); 517 name = devname; 518 } 519 /* No preexisting struct cdev *, create one */ 520 *dev = make_dev_credf(MAKEDEV_REF, &drv->cdevsw, u, cred, 521 UID_UUCP, GID_DIALER, 0600, "%s", name); 522 } 523 524 if_clone_create(name, namelen, NULL); 525 out: 526 CURVNET_RESTORE(); 527 } 528 529 static void 530 tun_destroy(struct tuntap_softc *tp) 531 { 532 533 TUN_LOCK(tp); 534 tp->tun_flags |= TUN_DYING; 535 if ((tp->tun_flags & TUN_OPEN) != 0) 536 cv_wait_unlock(&tp->tun_cv, &tp->tun_mtx); 537 else 538 TUN_UNLOCK(tp); 539 540 CURVNET_SET(TUN2IFP(tp)->if_vnet); 541 542 destroy_dev(tp->tun_dev); 543 seldrain(&tp->tun_rsel); 544 knlist_clear(&tp->tun_rsel.si_note, 0); 545 knlist_destroy(&tp->tun_rsel.si_note); 546 if ((tp->tun_flags & TUN_L2) != 0) { 547 ether_ifdetach(TUN2IFP(tp)); 548 } else { 549 bpfdetach(TUN2IFP(tp)); 550 if_detach(TUN2IFP(tp)); 551 } 552 sx_xlock(&tun_ioctl_sx); 553 TUN2IFP(tp)->if_softc = NULL; 554 sx_xunlock(&tun_ioctl_sx); 555 free_unr(tp->tun_drv->unrhdr, TUN2IFP(tp)->if_dunit); 556 if_free(TUN2IFP(tp)); 557 mtx_destroy(&tp->tun_mtx); 558 cv_destroy(&tp->tun_cv); 559 free(tp, M_TUN); 560 CURVNET_RESTORE(); 561 } 562 563 static int 564 tun_clone_destroy(struct if_clone *ifc __unused, struct ifnet *ifp) 565 { 566 struct tuntap_softc *tp = ifp->if_softc; 567 568 mtx_lock(&tunmtx); 569 TAILQ_REMOVE(&tunhead, tp, tun_list); 570 mtx_unlock(&tunmtx); 571 tun_destroy(tp); 572 573 return (0); 574 } 575 576 static void 577 vnet_tun_init(const void *unused __unused) 578 { 579 struct tuntap_driver *drv; 580 struct tuntap_driver_cloner *drvc; 581 int i; 582 583 for (i = 0; i < nitems(tuntap_drivers); ++i) { 584 drv = &tuntap_drivers[i]; 585 drvc = malloc(sizeof(*drvc), M_TUN, M_WAITOK | M_ZERO); 586 587 drvc->drv = drv; 588 drvc->cloner = if_clone_advanced(drv->cdevsw.d_name, 0, 589 drv->clone_match_fn, drv->clone_create_fn, 590 drv->clone_destroy_fn); 591 SLIST_INSERT_HEAD(&V_tuntap_driver_cloners, drvc, link); 592 }; 593 } 594 VNET_SYSINIT(vnet_tun_init, SI_SUB_PROTO_IF, SI_ORDER_ANY, 595 vnet_tun_init, NULL); 596 597 static void 598 vnet_tun_uninit(const void *unused __unused) 599 { 600 struct tuntap_driver_cloner *drvc; 601 602 while (!SLIST_EMPTY(&V_tuntap_driver_cloners)) { 603 drvc = SLIST_FIRST(&V_tuntap_driver_cloners); 604 SLIST_REMOVE_HEAD(&V_tuntap_driver_cloners, link); 605 606 if_clone_detach(drvc->cloner); 607 free(drvc, M_TUN); 608 } 609 } 610 VNET_SYSUNINIT(vnet_tun_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY, 611 vnet_tun_uninit, NULL); 612 613 static void 614 tun_uninit(const void *unused __unused) 615 { 616 struct tuntap_driver *drv; 617 struct tuntap_softc *tp; 618 int i; 619 620 EVENTHANDLER_DEREGISTER(dev_clone, tag); 621 drain_dev_clone_events(); 622 623 mtx_lock(&tunmtx); 624 while ((tp = TAILQ_FIRST(&tunhead)) != NULL) { 625 TAILQ_REMOVE(&tunhead, tp, tun_list); 626 mtx_unlock(&tunmtx); 627 tun_destroy(tp); 628 mtx_lock(&tunmtx); 629 } 630 mtx_unlock(&tunmtx); 631 for (i = 0; i < nitems(tuntap_drivers); ++i) { 632 drv = &tuntap_drivers[i]; 633 delete_unrhdr(drv->unrhdr); 634 clone_cleanup(&drv->clones); 635 } 636 mtx_destroy(&tunmtx); 637 } 638 SYSUNINIT(tun_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY, tun_uninit, NULL); 639 640 static int 641 tuntapmodevent(module_t mod, int type, void *data) 642 { 643 struct tuntap_driver *drv; 644 int i; 645 646 switch (type) { 647 case MOD_LOAD: 648 mtx_init(&tunmtx, "tunmtx", NULL, MTX_DEF); 649 for (i = 0; i < nitems(tuntap_drivers); ++i) { 650 drv = &tuntap_drivers[i]; 651 clone_setup(&drv->clones); 652 drv->unrhdr = new_unrhdr(0, IF_MAXUNIT, &tunmtx); 653 } 654 tag = EVENTHANDLER_REGISTER(dev_clone, tunclone, 0, 1000); 655 if (tag == NULL) 656 return (ENOMEM); 657 break; 658 case MOD_UNLOAD: 659 /* See tun_uninit, so it's done after the vnet_sysuninit() */ 660 break; 661 default: 662 return EOPNOTSUPP; 663 } 664 return 0; 665 } 666 667 static moduledata_t tuntap_mod = { 668 "if_tuntap", 669 tuntapmodevent, 670 0 671 }; 672 673 DECLARE_MODULE(if_tuntap, tuntap_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 674 MODULE_VERSION(if_tuntap, 1); 675 676 static void 677 tunstart(struct ifnet *ifp) 678 { 679 struct tuntap_softc *tp = ifp->if_softc; 680 struct mbuf *m; 681 682 TUNDEBUG(ifp, "starting\n"); 683 if (ALTQ_IS_ENABLED(&ifp->if_snd)) { 684 IFQ_LOCK(&ifp->if_snd); 685 IFQ_POLL_NOLOCK(&ifp->if_snd, m); 686 if (m == NULL) { 687 IFQ_UNLOCK(&ifp->if_snd); 688 return; 689 } 690 IFQ_UNLOCK(&ifp->if_snd); 691 } 692 693 TUN_LOCK(tp); 694 if (tp->tun_flags & TUN_RWAIT) { 695 tp->tun_flags &= ~TUN_RWAIT; 696 wakeup(tp); 697 } 698 selwakeuppri(&tp->tun_rsel, PZERO + 1); 699 KNOTE_LOCKED(&tp->tun_rsel.si_note, 0); 700 if (tp->tun_flags & TUN_ASYNC && tp->tun_sigio) { 701 TUN_UNLOCK(tp); 702 pgsigio(&tp->tun_sigio, SIGIO, 0); 703 } else 704 TUN_UNLOCK(tp); 705 } 706 707 /* 708 * tunstart_l2 709 * 710 * queue packets from higher level ready to put out 711 */ 712 static void 713 tunstart_l2(struct ifnet *ifp) 714 { 715 struct tuntap_softc *tp = ifp->if_softc; 716 717 TUNDEBUG(ifp, "starting\n"); 718 719 /* 720 * do not junk pending output if we are in VMnet mode. 721 * XXX: can this do any harm because of queue overflow? 722 */ 723 724 TUN_LOCK(tp); 725 if (((tp->tun_flags & TUN_VMNET) == 0) && 726 ((tp->tun_flags & TUN_READY) != TUN_READY)) { 727 struct mbuf *m; 728 729 /* Unlocked read. */ 730 TUNDEBUG(ifp, "not ready, tun_flags = 0x%x\n", tp->tun_flags); 731 732 for (;;) { 733 IF_DEQUEUE(&ifp->if_snd, m); 734 if (m != NULL) { 735 m_freem(m); 736 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 737 } else 738 break; 739 } 740 TUN_UNLOCK(tp); 741 742 return; 743 } 744 745 ifp->if_drv_flags |= IFF_DRV_OACTIVE; 746 747 if (!IFQ_IS_EMPTY(&ifp->if_snd)) { 748 if (tp->tun_flags & TUN_RWAIT) { 749 tp->tun_flags &= ~TUN_RWAIT; 750 wakeup(tp); 751 } 752 753 if ((tp->tun_flags & TUN_ASYNC) && (tp->tun_sigio != NULL)) { 754 TUN_UNLOCK(tp); 755 pgsigio(&tp->tun_sigio, SIGIO, 0); 756 TUN_LOCK(tp); 757 } 758 759 selwakeuppri(&tp->tun_rsel, PZERO+1); 760 KNOTE_LOCKED(&tp->tun_rsel.si_note, 0); 761 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); /* obytes are counted in ether_output */ 762 } 763 764 ifp->if_drv_flags &= ~IFF_DRV_OACTIVE; 765 TUN_UNLOCK(tp); 766 } /* tunstart_l2 */ 767 768 769 /* XXX: should return an error code so it can fail. */ 770 static void 771 tuncreate(struct cdev *dev, struct tuntap_driver *drv) 772 { 773 struct tuntap_softc *sc; 774 struct ifnet *ifp; 775 struct ether_addr eaddr; 776 int iflags; 777 u_char type; 778 779 sc = malloc(sizeof(*sc), M_TUN, M_WAITOK | M_ZERO); 780 mtx_init(&sc->tun_mtx, "tun_mtx", NULL, MTX_DEF); 781 cv_init(&sc->tun_cv, "tun_condvar"); 782 sc->tun_flags = drv->ident_flags; 783 sc->tun_dev = dev; 784 sc->tun_drv = drv; 785 mtx_lock(&tunmtx); 786 TAILQ_INSERT_TAIL(&tunhead, sc, tun_list); 787 mtx_unlock(&tunmtx); 788 789 iflags = IFF_MULTICAST; 790 if ((sc->tun_flags & TUN_L2) != 0) { 791 type = IFT_ETHER; 792 iflags |= IFF_BROADCAST | IFF_SIMPLEX; 793 } else { 794 type = IFT_PPP; 795 iflags |= IFF_POINTOPOINT; 796 } 797 ifp = sc->tun_ifp = if_alloc(type); 798 if (ifp == NULL) 799 panic("%s%d: failed to if_alloc() interface.\n", 800 drv->cdevsw.d_name, dev2unit(dev)); 801 ifp->if_softc = sc; 802 if_initname(ifp, drv->cdevsw.d_name, dev2unit(dev)); 803 ifp->if_ioctl = tunifioctl; 804 ifp->if_flags = iflags; 805 IFQ_SET_MAXLEN(&ifp->if_snd, ifqmaxlen); 806 knlist_init_mtx(&sc->tun_rsel.si_note, &sc->tun_mtx); 807 ifp->if_capabilities |= IFCAP_LINKSTATE; 808 ifp->if_capenable |= IFCAP_LINKSTATE; 809 810 if ((sc->tun_flags & TUN_L2) != 0) { 811 ifp->if_mtu = ETHERMTU; 812 ifp->if_init = tunifinit; 813 ifp->if_start = tunstart_l2; 814 815 ether_gen_addr(ifp, &eaddr); 816 ether_ifattach(ifp, eaddr.octet); 817 } else { 818 ifp->if_mtu = TUNMTU; 819 ifp->if_start = tunstart; 820 ifp->if_output = tunoutput; 821 822 ifp->if_snd.ifq_drv_maxlen = 0; 823 IFQ_SET_READY(&ifp->if_snd); 824 825 if_attach(ifp); 826 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 827 } 828 dev->si_drv1 = sc; 829 830 TUN_LOCK(sc); 831 sc->tun_flags |= TUN_INITED; 832 TUN_UNLOCK(sc); 833 834 TUNDEBUG(ifp, "interface %s is created, minor = %#x\n", 835 ifp->if_xname, dev2unit(dev)); 836 } 837 838 static int 839 tunopen(struct cdev *dev, int flag, int mode, struct thread *td) 840 { 841 struct ifnet *ifp; 842 struct tuntap_driver *drv; 843 struct tuntap_softc *tp; 844 int error, tunflags; 845 846 tunflags = 0; 847 CURVNET_SET(TD_TO_VNET(td)); 848 error = tuntap_name2info(dev->si_name, NULL, &tunflags); 849 if (error != 0) { 850 CURVNET_RESTORE(); 851 return (error); /* Shouldn't happen */ 852 } 853 854 if ((tunflags & TUN_L2) != 0) { 855 /* Restrict? */ 856 if (tap_allow_uopen == 0) { 857 error = priv_check(td, PRIV_NET_TAP); 858 if (error != 0) { 859 CURVNET_RESTORE(); 860 return (error); 861 } 862 } 863 } 864 865 /* 866 * XXXRW: Non-atomic test and set of dev->si_drv1 requires 867 * synchronization. 868 */ 869 tp = dev->si_drv1; 870 if (!tp) { 871 drv = tuntap_driver_from_flags(tunflags); 872 if (drv == NULL) { 873 CURVNET_RESTORE(); 874 return (ENXIO); 875 } 876 tuncreate(dev, drv); 877 tp = dev->si_drv1; 878 } 879 880 TUN_LOCK(tp); 881 if ((tp->tun_flags & (TUN_OPEN | TUN_DYING)) != 0) { 882 TUN_UNLOCK(tp); 883 CURVNET_RESTORE(); 884 return (EBUSY); 885 } 886 887 ifp = TUN2IFP(tp); 888 889 if ((tp->tun_flags & TUN_L2) != 0) { 890 bcopy(IF_LLADDR(ifp), tp->tun_ether.octet, 891 sizeof(tp->tun_ether.octet)); 892 893 ifp->if_drv_flags |= IFF_DRV_RUNNING; 894 ifp->if_drv_flags &= ~IFF_DRV_OACTIVE; 895 896 if (tapuponopen) 897 ifp->if_flags |= IFF_UP; 898 } 899 900 tp->tun_pid = td->td_proc->p_pid; 901 tp->tun_flags |= TUN_OPEN; 902 903 if_link_state_change(ifp, LINK_STATE_UP); 904 TUNDEBUG(ifp, "open\n"); 905 TUN_UNLOCK(tp); 906 CURVNET_RESTORE(); 907 return (0); 908 } 909 910 /* 911 * tunclose - close the device - mark i/f down & delete 912 * routing info 913 */ 914 static int 915 tunclose(struct cdev *dev, int foo, int bar, struct thread *td) 916 { 917 struct tuntap_softc *tp; 918 struct ifnet *ifp; 919 bool l2tun; 920 921 tp = dev->si_drv1; 922 ifp = TUN2IFP(tp); 923 924 TUN_LOCK(tp); 925 /* 926 * Simply close the device if this isn't the controlling process. This 927 * may happen if, for instance, the tunnel has been handed off to 928 * another process. The original controller should be able to close it 929 * without putting us into an inconsistent state. 930 */ 931 if (td->td_proc->p_pid != tp->tun_pid) { 932 TUN_UNLOCK(tp); 933 return (0); 934 } 935 936 /* 937 * junk all pending output 938 */ 939 CURVNET_SET(ifp->if_vnet); 940 941 l2tun = false; 942 if ((tp->tun_flags & TUN_L2) != 0) { 943 l2tun = true; 944 IF_DRAIN(&ifp->if_snd); 945 } else { 946 IFQ_PURGE(&ifp->if_snd); 947 } 948 949 /* For vmnet, we won't do most of the address/route bits */ 950 if ((tp->tun_flags & TUN_VMNET) != 0 || 951 (l2tun && (ifp->if_flags & IFF_LINK0) != 0)) 952 goto out; 953 954 if (ifp->if_flags & IFF_UP) { 955 TUN_UNLOCK(tp); 956 if_down(ifp); 957 TUN_LOCK(tp); 958 } 959 960 /* Delete all addresses and routes which reference this interface. */ 961 if (ifp->if_drv_flags & IFF_DRV_RUNNING) { 962 struct ifaddr *ifa; 963 964 ifp->if_drv_flags &= ~IFF_DRV_RUNNING; 965 TUN_UNLOCK(tp); 966 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 967 /* deal w/IPv4 PtP destination; unlocked read */ 968 if (!l2tun && ifa->ifa_addr->sa_family == AF_INET) { 969 rtinit(ifa, (int)RTM_DELETE, 970 tp->tun_flags & TUN_DSTADDR ? RTF_HOST : 0); 971 } else { 972 rtinit(ifa, (int)RTM_DELETE, 0); 973 } 974 } 975 if_purgeaddrs(ifp); 976 TUN_LOCK(tp); 977 } 978 979 out: 980 if_link_state_change(ifp, LINK_STATE_DOWN); 981 CURVNET_RESTORE(); 982 983 funsetown(&tp->tun_sigio); 984 selwakeuppri(&tp->tun_rsel, PZERO + 1); 985 KNOTE_LOCKED(&tp->tun_rsel.si_note, 0); 986 TUNDEBUG (ifp, "closed\n"); 987 tp->tun_flags &= ~TUN_OPEN; 988 tp->tun_pid = 0; 989 990 cv_broadcast(&tp->tun_cv); 991 TUN_UNLOCK(tp); 992 return (0); 993 } 994 995 static void 996 tuninit(struct ifnet *ifp) 997 { 998 struct tuntap_softc *tp = ifp->if_softc; 999 #ifdef INET 1000 struct ifaddr *ifa; 1001 #endif 1002 1003 TUNDEBUG(ifp, "tuninit\n"); 1004 1005 TUN_LOCK(tp); 1006 ifp->if_drv_flags |= IFF_DRV_RUNNING; 1007 if ((tp->tun_flags & TUN_L2) == 0) { 1008 ifp->if_flags |= IFF_UP; 1009 getmicrotime(&ifp->if_lastchange); 1010 #ifdef INET 1011 if_addr_rlock(ifp); 1012 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1013 if (ifa->ifa_addr->sa_family == AF_INET) { 1014 struct sockaddr_in *si; 1015 1016 si = (struct sockaddr_in *)ifa->ifa_addr; 1017 if (si->sin_addr.s_addr) 1018 tp->tun_flags |= TUN_IASET; 1019 1020 si = (struct sockaddr_in *)ifa->ifa_dstaddr; 1021 if (si && si->sin_addr.s_addr) 1022 tp->tun_flags |= TUN_DSTADDR; 1023 } 1024 } 1025 if_addr_runlock(ifp); 1026 #endif 1027 TUN_UNLOCK(tp); 1028 } else { 1029 ifp->if_drv_flags &= ~IFF_DRV_OACTIVE; 1030 TUN_UNLOCK(tp); 1031 /* attempt to start output */ 1032 tunstart_l2(ifp); 1033 } 1034 1035 } 1036 1037 /* 1038 * Used only for l2 tunnel. 1039 */ 1040 static void 1041 tunifinit(void *xtp) 1042 { 1043 struct tuntap_softc *tp; 1044 1045 tp = (struct tuntap_softc *)xtp; 1046 tuninit(tp->tun_ifp); 1047 } 1048 1049 /* 1050 * Process an ioctl request. 1051 */ 1052 static int 1053 tunifioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 1054 { 1055 struct ifreq *ifr = (struct ifreq *)data; 1056 struct tuntap_softc *tp; 1057 struct ifstat *ifs; 1058 struct ifmediareq *ifmr; 1059 int dummy, error = 0; 1060 bool l2tun; 1061 1062 ifmr = NULL; 1063 sx_xlock(&tun_ioctl_sx); 1064 tp = ifp->if_softc; 1065 if (tp == NULL) { 1066 error = ENXIO; 1067 goto bad; 1068 } 1069 l2tun = (tp->tun_flags & TUN_L2) != 0; 1070 switch(cmd) { 1071 case SIOCGIFSTATUS: 1072 ifs = (struct ifstat *)data; 1073 TUN_LOCK(tp); 1074 if (tp->tun_pid) 1075 snprintf(ifs->ascii, sizeof(ifs->ascii), 1076 "\tOpened by PID %d\n", tp->tun_pid); 1077 else 1078 ifs->ascii[0] = '\0'; 1079 TUN_UNLOCK(tp); 1080 break; 1081 case SIOCSIFADDR: 1082 if (l2tun) 1083 error = ether_ioctl(ifp, cmd, data); 1084 else 1085 tuninit(ifp); 1086 if (error == 0) 1087 TUNDEBUG(ifp, "address set\n"); 1088 break; 1089 case SIOCSIFMTU: 1090 ifp->if_mtu = ifr->ifr_mtu; 1091 TUNDEBUG(ifp, "mtu set\n"); 1092 break; 1093 case SIOCSIFFLAGS: 1094 case SIOCADDMULTI: 1095 case SIOCDELMULTI: 1096 break; 1097 case SIOCGIFMEDIA: 1098 if (!l2tun) { 1099 error = EINVAL; 1100 break; 1101 } 1102 1103 ifmr = (struct ifmediareq *)data; 1104 dummy = ifmr->ifm_count; 1105 ifmr->ifm_count = 1; 1106 ifmr->ifm_status = IFM_AVALID; 1107 ifmr->ifm_active = IFM_ETHER; 1108 if (tp->tun_flags & TUN_OPEN) 1109 ifmr->ifm_status |= IFM_ACTIVE; 1110 ifmr->ifm_current = ifmr->ifm_active; 1111 if (dummy >= 1) { 1112 int media = IFM_ETHER; 1113 error = copyout(&media, ifmr->ifm_ulist, sizeof(int)); 1114 } 1115 break; 1116 default: 1117 if (l2tun) { 1118 error = ether_ioctl(ifp, cmd, data); 1119 } else { 1120 error = EINVAL; 1121 } 1122 } 1123 bad: 1124 sx_xunlock(&tun_ioctl_sx); 1125 return (error); 1126 } 1127 1128 /* 1129 * tunoutput - queue packets from higher level ready to put out. 1130 */ 1131 static int 1132 tunoutput(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst, 1133 struct route *ro) 1134 { 1135 struct tuntap_softc *tp = ifp->if_softc; 1136 u_short cached_tun_flags; 1137 int error; 1138 u_int32_t af; 1139 1140 TUNDEBUG (ifp, "tunoutput\n"); 1141 1142 #ifdef MAC 1143 error = mac_ifnet_check_transmit(ifp, m0); 1144 if (error) { 1145 m_freem(m0); 1146 return (error); 1147 } 1148 #endif 1149 1150 /* Could be unlocked read? */ 1151 TUN_LOCK(tp); 1152 cached_tun_flags = tp->tun_flags; 1153 TUN_UNLOCK(tp); 1154 if ((cached_tun_flags & TUN_READY) != TUN_READY) { 1155 TUNDEBUG (ifp, "not ready 0%o\n", tp->tun_flags); 1156 m_freem (m0); 1157 return (EHOSTDOWN); 1158 } 1159 1160 if ((ifp->if_flags & IFF_UP) != IFF_UP) { 1161 m_freem (m0); 1162 return (EHOSTDOWN); 1163 } 1164 1165 /* BPF writes need to be handled specially. */ 1166 if (dst->sa_family == AF_UNSPEC) 1167 bcopy(dst->sa_data, &af, sizeof(af)); 1168 else 1169 af = dst->sa_family; 1170 1171 if (bpf_peers_present(ifp->if_bpf)) 1172 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m0); 1173 1174 /* prepend sockaddr? this may abort if the mbuf allocation fails */ 1175 if (cached_tun_flags & TUN_LMODE) { 1176 /* allocate space for sockaddr */ 1177 M_PREPEND(m0, dst->sa_len, M_NOWAIT); 1178 1179 /* if allocation failed drop packet */ 1180 if (m0 == NULL) { 1181 if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1); 1182 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 1183 return (ENOBUFS); 1184 } else { 1185 bcopy(dst, m0->m_data, dst->sa_len); 1186 } 1187 } 1188 1189 if (cached_tun_flags & TUN_IFHEAD) { 1190 /* Prepend the address family */ 1191 M_PREPEND(m0, 4, M_NOWAIT); 1192 1193 /* if allocation failed drop packet */ 1194 if (m0 == NULL) { 1195 if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1); 1196 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 1197 return (ENOBUFS); 1198 } else 1199 *(u_int32_t *)m0->m_data = htonl(af); 1200 } else { 1201 #ifdef INET 1202 if (af != AF_INET) 1203 #endif 1204 { 1205 m_freem(m0); 1206 return (EAFNOSUPPORT); 1207 } 1208 } 1209 1210 error = (ifp->if_transmit)(ifp, m0); 1211 if (error) 1212 return (ENOBUFS); 1213 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 1214 return (0); 1215 } 1216 1217 /* 1218 * the cdevsw interface is now pretty minimal. 1219 */ 1220 static int 1221 tunioctl(struct cdev *dev, u_long cmd, caddr_t data, int flag, 1222 struct thread *td) 1223 { 1224 struct ifreq ifr, *ifrp; 1225 struct tuntap_softc *tp = dev->si_drv1; 1226 struct tuninfo *tunp; 1227 int error, iflags; 1228 #if defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD5) || \ 1229 defined(COMPAT_FREEBSD4) 1230 int ival; 1231 #endif 1232 bool l2tun; 1233 1234 l2tun = (tp->tun_flags & TUN_L2) != 0; 1235 if (l2tun) { 1236 /* tap specific ioctls */ 1237 switch(cmd) { 1238 case TAPGIFNAME: 1239 ifrp = (struct ifreq *)data; 1240 strlcpy(ifrp->ifr_name, TUN2IFP(tp)->if_xname, 1241 IFNAMSIZ); 1242 1243 return (0); 1244 /* VMware/VMnet port ioctl's */ 1245 #if defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD5) || \ 1246 defined(COMPAT_FREEBSD4) 1247 case _IO('V', 0): 1248 ival = IOCPARM_IVAL(data); 1249 data = (caddr_t)&ival; 1250 /* FALLTHROUGH */ 1251 #endif 1252 case VMIO_SIOCSIFFLAGS: /* VMware/VMnet SIOCSIFFLAGS */ 1253 iflags = *(int *)data; 1254 iflags &= TUN_VMIO_FLAG_MASK; 1255 iflags &= ~IFF_CANTCHANGE; 1256 iflags |= IFF_UP; 1257 1258 TUN_LOCK(tp); 1259 TUN2IFP(tp)->if_flags = iflags | 1260 (TUN2IFP(tp)->if_flags & IFF_CANTCHANGE); 1261 TUN_UNLOCK(tp); 1262 1263 return (0); 1264 case SIOCGIFADDR: /* get MAC address of the remote side */ 1265 TUN_LOCK(tp); 1266 bcopy(&tp->tun_ether.octet, data, 1267 sizeof(tp->tun_ether.octet)); 1268 TUN_UNLOCK(tp); 1269 1270 return (0); 1271 case SIOCSIFADDR: /* set MAC address of the remote side */ 1272 TUN_LOCK(tp); 1273 bcopy(data, &tp->tun_ether.octet, 1274 sizeof(tp->tun_ether.octet)); 1275 TUN_UNLOCK(tp); 1276 1277 return (0); 1278 } 1279 1280 /* Fall through to the common ioctls if unhandled */ 1281 } else { 1282 switch (cmd) { 1283 case TUNSLMODE: 1284 TUN_LOCK(tp); 1285 if (*(int *)data) { 1286 tp->tun_flags |= TUN_LMODE; 1287 tp->tun_flags &= ~TUN_IFHEAD; 1288 } else 1289 tp->tun_flags &= ~TUN_LMODE; 1290 TUN_UNLOCK(tp); 1291 1292 return (0); 1293 case TUNSIFHEAD: 1294 TUN_LOCK(tp); 1295 if (*(int *)data) { 1296 tp->tun_flags |= TUN_IFHEAD; 1297 tp->tun_flags &= ~TUN_LMODE; 1298 } else 1299 tp->tun_flags &= ~TUN_IFHEAD; 1300 TUN_UNLOCK(tp); 1301 1302 return (0); 1303 case TUNGIFHEAD: 1304 TUN_LOCK(tp); 1305 *(int *)data = (tp->tun_flags & TUN_IFHEAD) ? 1 : 0; 1306 TUN_UNLOCK(tp); 1307 1308 return (0); 1309 case TUNSIFMODE: 1310 /* deny this if UP */ 1311 if (TUN2IFP(tp)->if_flags & IFF_UP) 1312 return (EBUSY); 1313 1314 switch (*(int *)data & ~IFF_MULTICAST) { 1315 case IFF_POINTOPOINT: 1316 case IFF_BROADCAST: 1317 TUN_LOCK(tp); 1318 TUN2IFP(tp)->if_flags &= 1319 ~(IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST); 1320 TUN2IFP(tp)->if_flags |= *(int *)data; 1321 TUN_UNLOCK(tp); 1322 1323 break; 1324 default: 1325 return (EINVAL); 1326 } 1327 1328 return (0); 1329 case TUNSIFPID: 1330 TUN_LOCK(tp); 1331 tp->tun_pid = curthread->td_proc->p_pid; 1332 TUN_UNLOCK(tp); 1333 1334 return (0); 1335 } 1336 /* Fall through to the common ioctls if unhandled */ 1337 } 1338 1339 switch (cmd) { 1340 case TUNSIFINFO: 1341 tunp = (struct tuninfo *)data; 1342 if (TUN2IFP(tp)->if_type != tunp->type) 1343 return (EPROTOTYPE); 1344 TUN_LOCK(tp); 1345 if (TUN2IFP(tp)->if_mtu != tunp->mtu) { 1346 strlcpy(ifr.ifr_name, if_name(TUN2IFP(tp)), IFNAMSIZ); 1347 ifr.ifr_mtu = tunp->mtu; 1348 CURVNET_SET(TUN2IFP(tp)->if_vnet); 1349 error = ifhwioctl(SIOCSIFMTU, TUN2IFP(tp), 1350 (caddr_t)&ifr, td); 1351 CURVNET_RESTORE(); 1352 if (error) { 1353 TUN_UNLOCK(tp); 1354 return (error); 1355 } 1356 } 1357 TUN2IFP(tp)->if_baudrate = tunp->baudrate; 1358 TUN_UNLOCK(tp); 1359 break; 1360 case TUNGIFINFO: 1361 tunp = (struct tuninfo *)data; 1362 TUN_LOCK(tp); 1363 tunp->mtu = TUN2IFP(tp)->if_mtu; 1364 tunp->type = TUN2IFP(tp)->if_type; 1365 tunp->baudrate = TUN2IFP(tp)->if_baudrate; 1366 TUN_UNLOCK(tp); 1367 break; 1368 case TUNSDEBUG: 1369 tundebug = *(int *)data; 1370 break; 1371 case TUNGDEBUG: 1372 *(int *)data = tundebug; 1373 break; 1374 case FIONBIO: 1375 break; 1376 case FIOASYNC: 1377 TUN_LOCK(tp); 1378 if (*(int *)data) 1379 tp->tun_flags |= TUN_ASYNC; 1380 else 1381 tp->tun_flags &= ~TUN_ASYNC; 1382 TUN_UNLOCK(tp); 1383 break; 1384 case FIONREAD: 1385 if (!IFQ_IS_EMPTY(&TUN2IFP(tp)->if_snd)) { 1386 struct mbuf *mb; 1387 IFQ_LOCK(&TUN2IFP(tp)->if_snd); 1388 IFQ_POLL_NOLOCK(&TUN2IFP(tp)->if_snd, mb); 1389 for (*(int *)data = 0; mb != NULL; mb = mb->m_next) 1390 *(int *)data += mb->m_len; 1391 IFQ_UNLOCK(&TUN2IFP(tp)->if_snd); 1392 } else 1393 *(int *)data = 0; 1394 break; 1395 case FIOSETOWN: 1396 return (fsetown(*(int *)data, &tp->tun_sigio)); 1397 1398 case FIOGETOWN: 1399 *(int *)data = fgetown(&tp->tun_sigio); 1400 return (0); 1401 1402 /* This is deprecated, FIOSETOWN should be used instead. */ 1403 case TIOCSPGRP: 1404 return (fsetown(-(*(int *)data), &tp->tun_sigio)); 1405 1406 /* This is deprecated, FIOGETOWN should be used instead. */ 1407 case TIOCGPGRP: 1408 *(int *)data = -fgetown(&tp->tun_sigio); 1409 return (0); 1410 1411 default: 1412 return (ENOTTY); 1413 } 1414 return (0); 1415 } 1416 1417 /* 1418 * The cdevsw read interface - reads a packet at a time, or at 1419 * least as much of a packet as can be read. 1420 */ 1421 static int 1422 tunread(struct cdev *dev, struct uio *uio, int flag) 1423 { 1424 struct tuntap_softc *tp = dev->si_drv1; 1425 struct ifnet *ifp = TUN2IFP(tp); 1426 struct mbuf *m; 1427 int error=0, len; 1428 1429 TUNDEBUG (ifp, "read\n"); 1430 TUN_LOCK(tp); 1431 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 1432 TUN_UNLOCK(tp); 1433 TUNDEBUG (ifp, "not ready 0%o\n", tp->tun_flags); 1434 return (EHOSTDOWN); 1435 } 1436 1437 tp->tun_flags &= ~TUN_RWAIT; 1438 1439 do { 1440 IFQ_DEQUEUE(&ifp->if_snd, m); 1441 if (m == NULL) { 1442 if (flag & O_NONBLOCK) { 1443 TUN_UNLOCK(tp); 1444 return (EWOULDBLOCK); 1445 } 1446 tp->tun_flags |= TUN_RWAIT; 1447 error = mtx_sleep(tp, &tp->tun_mtx, PCATCH | (PZERO + 1), 1448 "tunread", 0); 1449 if (error != 0) { 1450 TUN_UNLOCK(tp); 1451 return (error); 1452 } 1453 } 1454 } while (m == NULL); 1455 TUN_UNLOCK(tp); 1456 1457 if ((tp->tun_flags & TUN_L2) != 0) 1458 BPF_MTAP(ifp, m); 1459 1460 while (m && uio->uio_resid > 0 && error == 0) { 1461 len = min(uio->uio_resid, m->m_len); 1462 if (len != 0) 1463 error = uiomove(mtod(m, void *), len, uio); 1464 m = m_free(m); 1465 } 1466 1467 if (m) { 1468 TUNDEBUG(ifp, "Dropping mbuf\n"); 1469 m_freem(m); 1470 } 1471 return (error); 1472 } 1473 1474 static int 1475 tunwrite_l2(struct tuntap_softc *tp, struct mbuf *m) 1476 { 1477 struct ether_header *eh; 1478 struct ifnet *ifp; 1479 1480 ifp = TUN2IFP(tp); 1481 1482 /* 1483 * Only pass a unicast frame to ether_input(), if it would 1484 * actually have been received by non-virtual hardware. 1485 */ 1486 if (m->m_len < sizeof(struct ether_header)) { 1487 m_freem(m); 1488 return (0); 1489 } 1490 1491 eh = mtod(m, struct ether_header *); 1492 1493 if (eh && (ifp->if_flags & IFF_PROMISC) == 0 && 1494 !ETHER_IS_MULTICAST(eh->ether_dhost) && 1495 bcmp(eh->ether_dhost, IF_LLADDR(ifp), ETHER_ADDR_LEN) != 0) { 1496 m_freem(m); 1497 return (0); 1498 } 1499 1500 /* Pass packet up to parent. */ 1501 CURVNET_SET(ifp->if_vnet); 1502 (*ifp->if_input)(ifp, m); 1503 CURVNET_RESTORE(); 1504 /* ibytes are counted in parent */ 1505 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 1506 return (0); 1507 } 1508 1509 static int 1510 tunwrite_l3(struct tuntap_softc *tp, struct mbuf *m) 1511 { 1512 struct ifnet *ifp; 1513 int family, isr; 1514 1515 ifp = TUN2IFP(tp); 1516 /* Could be unlocked read? */ 1517 TUN_LOCK(tp); 1518 if (tp->tun_flags & TUN_IFHEAD) { 1519 TUN_UNLOCK(tp); 1520 if (m->m_len < sizeof(family) && 1521 (m = m_pullup(m, sizeof(family))) == NULL) 1522 return (ENOBUFS); 1523 family = ntohl(*mtod(m, u_int32_t *)); 1524 m_adj(m, sizeof(family)); 1525 } else { 1526 TUN_UNLOCK(tp); 1527 family = AF_INET; 1528 } 1529 1530 BPF_MTAP2(ifp, &family, sizeof(family), m); 1531 1532 switch (family) { 1533 #ifdef INET 1534 case AF_INET: 1535 isr = NETISR_IP; 1536 break; 1537 #endif 1538 #ifdef INET6 1539 case AF_INET6: 1540 isr = NETISR_IPV6; 1541 break; 1542 #endif 1543 default: 1544 m_freem(m); 1545 return (EAFNOSUPPORT); 1546 } 1547 random_harvest_queue(m, sizeof(*m), RANDOM_NET_TUN); 1548 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 1549 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 1550 CURVNET_SET(ifp->if_vnet); 1551 M_SETFIB(m, ifp->if_fib); 1552 netisr_dispatch(isr, m); 1553 CURVNET_RESTORE(); 1554 return (0); 1555 } 1556 1557 /* 1558 * the cdevsw write interface - an atomic write is a packet - or else! 1559 */ 1560 static int 1561 tunwrite(struct cdev *dev, struct uio *uio, int flag) 1562 { 1563 struct tuntap_softc *tp; 1564 struct ifnet *ifp; 1565 struct mbuf *m; 1566 uint32_t mru; 1567 int align; 1568 bool l2tun; 1569 1570 tp = dev->si_drv1; 1571 ifp = TUN2IFP(tp); 1572 TUNDEBUG(ifp, "tunwrite\n"); 1573 if ((ifp->if_flags & IFF_UP) != IFF_UP) 1574 /* ignore silently */ 1575 return (0); 1576 1577 if (uio->uio_resid == 0) 1578 return (0); 1579 1580 l2tun = (tp->tun_flags & TUN_L2) != 0; 1581 align = 0; 1582 mru = l2tun ? TAPMRU : TUNMRU; 1583 if (l2tun) 1584 align = ETHER_ALIGN; 1585 else if ((tp->tun_flags & TUN_IFHEAD) != 0) 1586 mru += sizeof(uint32_t); /* family */ 1587 if (uio->uio_resid < 0 || uio->uio_resid > mru) { 1588 TUNDEBUG(ifp, "len=%zd!\n", uio->uio_resid); 1589 return (EIO); 1590 } 1591 1592 if ((m = m_uiotombuf(uio, M_NOWAIT, 0, align, M_PKTHDR)) == NULL) { 1593 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 1594 return (ENOBUFS); 1595 } 1596 1597 m->m_pkthdr.rcvif = ifp; 1598 #ifdef MAC 1599 mac_ifnet_create_mbuf(ifp, m); 1600 #endif 1601 1602 if (l2tun) 1603 return (tunwrite_l2(tp, m)); 1604 1605 return (tunwrite_l3(tp, m)); 1606 } 1607 1608 /* 1609 * tunpoll - the poll interface, this is only useful on reads 1610 * really. The write detect always returns true, write never blocks 1611 * anyway, it either accepts the packet or drops it. 1612 */ 1613 static int 1614 tunpoll(struct cdev *dev, int events, struct thread *td) 1615 { 1616 struct tuntap_softc *tp = dev->si_drv1; 1617 struct ifnet *ifp = TUN2IFP(tp); 1618 int revents = 0; 1619 1620 TUNDEBUG(ifp, "tunpoll\n"); 1621 1622 if (events & (POLLIN | POLLRDNORM)) { 1623 IFQ_LOCK(&ifp->if_snd); 1624 if (!IFQ_IS_EMPTY(&ifp->if_snd)) { 1625 TUNDEBUG(ifp, "tunpoll q=%d\n", ifp->if_snd.ifq_len); 1626 revents |= events & (POLLIN | POLLRDNORM); 1627 } else { 1628 TUNDEBUG(ifp, "tunpoll waiting\n"); 1629 selrecord(td, &tp->tun_rsel); 1630 } 1631 IFQ_UNLOCK(&ifp->if_snd); 1632 } 1633 if (events & (POLLOUT | POLLWRNORM)) 1634 revents |= events & (POLLOUT | POLLWRNORM); 1635 1636 return (revents); 1637 } 1638 1639 /* 1640 * tunkqfilter - support for the kevent() system call. 1641 */ 1642 static int 1643 tunkqfilter(struct cdev *dev, struct knote *kn) 1644 { 1645 struct tuntap_softc *tp = dev->si_drv1; 1646 struct ifnet *ifp = TUN2IFP(tp); 1647 1648 switch(kn->kn_filter) { 1649 case EVFILT_READ: 1650 TUNDEBUG(ifp, "%s kqfilter: EVFILT_READ, minor = %#x\n", 1651 ifp->if_xname, dev2unit(dev)); 1652 kn->kn_fop = &tun_read_filterops; 1653 break; 1654 1655 case EVFILT_WRITE: 1656 TUNDEBUG(ifp, "%s kqfilter: EVFILT_WRITE, minor = %#x\n", 1657 ifp->if_xname, dev2unit(dev)); 1658 kn->kn_fop = &tun_write_filterops; 1659 break; 1660 1661 default: 1662 TUNDEBUG(ifp, "%s kqfilter: invalid filter, minor = %#x\n", 1663 ifp->if_xname, dev2unit(dev)); 1664 return(EINVAL); 1665 } 1666 1667 kn->kn_hook = tp; 1668 knlist_add(&tp->tun_rsel.si_note, kn, 0); 1669 1670 return (0); 1671 } 1672 1673 /* 1674 * Return true of there is data in the interface queue. 1675 */ 1676 static int 1677 tunkqread(struct knote *kn, long hint) 1678 { 1679 int ret; 1680 struct tuntap_softc *tp = kn->kn_hook; 1681 struct cdev *dev = tp->tun_dev; 1682 struct ifnet *ifp = TUN2IFP(tp); 1683 1684 if ((kn->kn_data = ifp->if_snd.ifq_len) > 0) { 1685 TUNDEBUG(ifp, 1686 "%s have data in the queue. Len = %d, minor = %#x\n", 1687 ifp->if_xname, ifp->if_snd.ifq_len, dev2unit(dev)); 1688 ret = 1; 1689 } else { 1690 TUNDEBUG(ifp, 1691 "%s waiting for data, minor = %#x\n", ifp->if_xname, 1692 dev2unit(dev)); 1693 ret = 0; 1694 } 1695 1696 return (ret); 1697 } 1698 1699 /* 1700 * Always can write, always return MTU in kn->data. 1701 */ 1702 static int 1703 tunkqwrite(struct knote *kn, long hint) 1704 { 1705 struct tuntap_softc *tp = kn->kn_hook; 1706 struct ifnet *ifp = TUN2IFP(tp); 1707 1708 kn->kn_data = ifp->if_mtu; 1709 1710 return (1); 1711 } 1712 1713 static void 1714 tunkqdetach(struct knote *kn) 1715 { 1716 struct tuntap_softc *tp = kn->kn_hook; 1717 1718 knlist_remove(&tp->tun_rsel.si_note, kn, 0); 1719 } 1720