if_tun.c revision 1.116
1 /* $NetBSD: if_tun.c,v 1.116 2014/03/16 05:20:30 dholland Exp $ */ 2 3 /* 4 * Copyright (c) 1988, Julian Onions <jpo (at) cs.nott.ac.uk> 5 * Nottingham University 1987. 6 * 7 * This source may be freely distributed, however I would be interested 8 * in any changes that are made. 9 * 10 * This driver takes packets off the IP i/f and hands them up to a 11 * user process to have its wicked way with. This driver has its 12 * roots in a similar driver written by Phil Cockcroft (formerly) at 13 * UCL. This driver is based much more on read/write/poll mode of 14 * operation though. 15 */ 16 17 #include <sys/cdefs.h> 18 __KERNEL_RCSID(0, "$NetBSD: if_tun.c,v 1.116 2014/03/16 05:20:30 dholland Exp $"); 19 20 #include "opt_inet.h" 21 22 #include <sys/param.h> 23 #include <sys/proc.h> 24 #include <sys/systm.h> 25 #include <sys/mbuf.h> 26 #include <sys/buf.h> 27 #include <sys/protosw.h> 28 #include <sys/socket.h> 29 #include <sys/ioctl.h> 30 #include <sys/errno.h> 31 #include <sys/syslog.h> 32 #include <sys/select.h> 33 #include <sys/poll.h> 34 #include <sys/file.h> 35 #include <sys/signalvar.h> 36 #include <sys/conf.h> 37 #include <sys/kauth.h> 38 #include <sys/simplelock.h> 39 #include <sys/mutex.h> 40 #include <sys/cpu.h> 41 42 #include <net/if.h> 43 #include <net/if_types.h> 44 #include <net/netisr.h> 45 #include <net/route.h> 46 47 48 #ifdef INET 49 #include <netinet/in.h> 50 #include <netinet/in_systm.h> 51 #include <netinet/in_var.h> 52 #include <netinet/ip.h> 53 #include <netinet/if_inarp.h> 54 #endif 55 56 57 #include <sys/time.h> 58 #include <net/bpf.h> 59 60 #include <net/if_tun.h> 61 62 #define TUNDEBUG if (tundebug) printf 63 int tundebug = 0; 64 65 extern int ifqmaxlen; 66 void tunattach(int); 67 68 static LIST_HEAD(, tun_softc) tun_softc_list; 69 static LIST_HEAD(, tun_softc) tunz_softc_list; 70 static struct simplelock tun_softc_lock; 71 72 static int tun_ioctl(struct ifnet *, u_long, void *); 73 static int tun_output(struct ifnet *, struct mbuf *, 74 const struct sockaddr *, struct rtentry *rt); 75 static int tun_clone_create(struct if_clone *, int); 76 static int tun_clone_destroy(struct ifnet *); 77 78 static struct if_clone tun_cloner = 79 IF_CLONE_INITIALIZER("tun", tun_clone_create, tun_clone_destroy); 80 81 static void tunattach0(struct tun_softc *); 82 static void tuninit(struct tun_softc *); 83 static void tun_i_softintr(void *); 84 static void tun_o_softintr(void *); 85 #ifdef ALTQ 86 static void tunstart(struct ifnet *); 87 #endif 88 static struct tun_softc *tun_find_unit(dev_t); 89 static struct tun_softc *tun_find_zunit(int); 90 91 static dev_type_open(tunopen); 92 static dev_type_close(tunclose); 93 static dev_type_read(tunread); 94 static dev_type_write(tunwrite); 95 static dev_type_ioctl(tunioctl); 96 static dev_type_poll(tunpoll); 97 static dev_type_kqfilter(tunkqfilter); 98 99 const struct cdevsw tun_cdevsw = { 100 .d_open = tunopen, 101 .d_close = tunclose, 102 .d_read = tunread, 103 .d_write = tunwrite, 104 .d_ioctl = tunioctl, 105 .d_stop = nostop, 106 .d_tty = notty, 107 .d_poll = tunpoll, 108 .d_mmap = nommap, 109 .d_kqfilter = tunkqfilter, 110 .d_flag = D_OTHER 111 }; 112 113 void 114 tunattach(int unused) 115 { 116 117 simple_lock_init(&tun_softc_lock); 118 LIST_INIT(&tun_softc_list); 119 LIST_INIT(&tunz_softc_list); 120 if_clone_attach(&tun_cloner); 121 } 122 123 /* 124 * Find driver instance from dev_t. 125 * Call at splnet(). 126 * Returns with tp locked (if found). 127 */ 128 static struct tun_softc * 129 tun_find_unit(dev_t dev) 130 { 131 struct tun_softc *tp; 132 int unit = minor(dev); 133 134 simple_lock(&tun_softc_lock); 135 LIST_FOREACH(tp, &tun_softc_list, tun_list) 136 if (unit == tp->tun_unit) 137 break; 138 if (tp) 139 mutex_enter(&tp->tun_lock); 140 simple_unlock(&tun_softc_lock); 141 142 return (tp); 143 } 144 145 /* 146 * Find zombie driver instance by unit number. 147 * Call at splnet(). 148 * Remove tp from list and return it unlocked (if found). 149 */ 150 static struct tun_softc * 151 tun_find_zunit(int unit) 152 { 153 struct tun_softc *tp; 154 155 simple_lock(&tun_softc_lock); 156 LIST_FOREACH(tp, &tunz_softc_list, tun_list) 157 if (unit == tp->tun_unit) 158 break; 159 if (tp) 160 LIST_REMOVE(tp, tun_list); 161 simple_unlock(&tun_softc_lock); 162 #ifdef DIAGNOSTIC 163 if (tp != NULL && (tp->tun_flags & (TUN_INITED|TUN_OPEN)) != TUN_OPEN) 164 printf("tun%d: inconsistent flags: %x\n", unit, tp->tun_flags); 165 #endif 166 167 return (tp); 168 } 169 170 static int 171 tun_clone_create(struct if_clone *ifc, int unit) 172 { 173 struct tun_softc *tp; 174 175 if ((tp = tun_find_zunit(unit)) == NULL) { 176 /* Allocate a new instance */ 177 tp = malloc(sizeof(*tp), M_DEVBUF, M_WAITOK|M_ZERO); 178 179 tp->tun_unit = unit; 180 mutex_init(&tp->tun_lock, MUTEX_DEFAULT, IPL_NET); 181 selinit(&tp->tun_rsel); 182 selinit(&tp->tun_wsel); 183 } else { 184 /* Revive tunnel instance; clear ifp part */ 185 (void)memset(&tp->tun_if, 0, sizeof(struct ifnet)); 186 } 187 188 if_initname(&tp->tun_if, ifc->ifc_name, unit); 189 tunattach0(tp); 190 tp->tun_flags |= TUN_INITED; 191 tp->tun_osih = softint_establish(SOFTINT_CLOCK, tun_o_softintr, tp); 192 tp->tun_isih = softint_establish(SOFTINT_CLOCK, tun_i_softintr, tp); 193 194 simple_lock(&tun_softc_lock); 195 LIST_INSERT_HEAD(&tun_softc_list, tp, tun_list); 196 simple_unlock(&tun_softc_lock); 197 198 return (0); 199 } 200 201 static void 202 tunattach0(struct tun_softc *tp) 203 { 204 struct ifnet *ifp; 205 206 ifp = &tp->tun_if; 207 ifp->if_softc = tp; 208 ifp->if_mtu = TUNMTU; 209 ifp->if_ioctl = tun_ioctl; 210 ifp->if_output = tun_output; 211 #ifdef ALTQ 212 ifp->if_start = tunstart; 213 #endif 214 ifp->if_flags = IFF_POINTOPOINT; 215 ifp->if_type = IFT_TUNNEL; 216 ifp->if_snd.ifq_maxlen = ifqmaxlen; 217 ifp->if_collisions = 0; 218 ifp->if_ierrors = 0; 219 ifp->if_oerrors = 0; 220 ifp->if_ipackets = 0; 221 ifp->if_opackets = 0; 222 ifp->if_ibytes = 0; 223 ifp->if_obytes = 0; 224 ifp->if_dlt = DLT_NULL; 225 IFQ_SET_READY(&ifp->if_snd); 226 if_attach(ifp); 227 if_alloc_sadl(ifp); 228 bpf_attach(ifp, DLT_NULL, sizeof(uint32_t)); 229 } 230 231 static int 232 tun_clone_destroy(struct ifnet *ifp) 233 { 234 struct tun_softc *tp = (void *)ifp; 235 int s, zombie = 0; 236 237 IF_PURGE(&ifp->if_snd); 238 ifp->if_flags &= ~IFF_RUNNING; 239 240 s = splnet(); 241 simple_lock(&tun_softc_lock); 242 mutex_enter(&tp->tun_lock); 243 LIST_REMOVE(tp, tun_list); 244 if (tp->tun_flags & TUN_OPEN) { 245 /* Hang on to storage until last close */ 246 zombie = 1; 247 tp->tun_flags &= ~TUN_INITED; 248 LIST_INSERT_HEAD(&tunz_softc_list, tp, tun_list); 249 } 250 simple_unlock(&tun_softc_lock); 251 252 if (tp->tun_flags & TUN_RWAIT) { 253 tp->tun_flags &= ~TUN_RWAIT; 254 wakeup((void *)tp); 255 } 256 selnotify(&tp->tun_rsel, 0, 0); 257 258 mutex_exit(&tp->tun_lock); 259 splx(s); 260 261 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 262 fownsignal(tp->tun_pgid, SIGIO, POLL_HUP, 0, NULL); 263 264 bpf_detach(ifp); 265 if_detach(ifp); 266 267 if (!zombie) { 268 seldestroy(&tp->tun_rsel); 269 seldestroy(&tp->tun_wsel); 270 softint_disestablish(tp->tun_osih); 271 softint_disestablish(tp->tun_isih); 272 mutex_destroy(&tp->tun_lock); 273 free(tp, M_DEVBUF); 274 } 275 276 return (0); 277 } 278 279 /* 280 * tunnel open - must be superuser & the device must be 281 * configured in 282 */ 283 static int 284 tunopen(dev_t dev, int flag, int mode, struct lwp *l) 285 { 286 struct ifnet *ifp; 287 struct tun_softc *tp; 288 int s, error; 289 290 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE_TUN, 291 KAUTH_REQ_NETWORK_INTERFACE_TUN_ADD, NULL, NULL, NULL); 292 if (error) 293 return (error); 294 295 s = splnet(); 296 tp = tun_find_unit(dev); 297 298 if (tp == NULL) { 299 (void)tun_clone_create(&tun_cloner, minor(dev)); 300 tp = tun_find_unit(dev); 301 if (tp == NULL) { 302 error = ENXIO; 303 goto out_nolock; 304 } 305 } 306 307 if (tp->tun_flags & TUN_OPEN) { 308 error = EBUSY; 309 goto out; 310 } 311 312 ifp = &tp->tun_if; 313 tp->tun_flags |= TUN_OPEN; 314 TUNDEBUG("%s: open\n", ifp->if_xname); 315 out: 316 mutex_exit(&tp->tun_lock); 317 out_nolock: 318 splx(s); 319 return (error); 320 } 321 322 /* 323 * tunclose - close the device - mark i/f down & delete 324 * routing info 325 */ 326 int 327 tunclose(dev_t dev, int flag, int mode, 328 struct lwp *l) 329 { 330 int s; 331 struct tun_softc *tp; 332 struct ifnet *ifp; 333 334 s = splnet(); 335 if ((tp = tun_find_zunit(minor(dev))) != NULL) { 336 /* interface was "destroyed" before the close */ 337 seldestroy(&tp->tun_rsel); 338 seldestroy(&tp->tun_wsel); 339 softint_disestablish(tp->tun_osih); 340 softint_disestablish(tp->tun_isih); 341 mutex_destroy(&tp->tun_lock); 342 free(tp, M_DEVBUF); 343 goto out_nolock; 344 } 345 346 if ((tp = tun_find_unit(dev)) == NULL) 347 goto out_nolock; 348 349 ifp = &tp->tun_if; 350 351 tp->tun_flags &= ~TUN_OPEN; 352 353 tp->tun_pgid = 0; 354 selnotify(&tp->tun_rsel, 0, 0); 355 356 TUNDEBUG ("%s: closed\n", ifp->if_xname); 357 mutex_exit(&tp->tun_lock); 358 359 /* 360 * junk all pending output 361 */ 362 IFQ_PURGE(&ifp->if_snd); 363 364 if (ifp->if_flags & IFF_UP) { 365 if_down(ifp); 366 if (ifp->if_flags & IFF_RUNNING) { 367 /* find internet addresses and delete routes */ 368 struct ifaddr *ifa; 369 IFADDR_FOREACH(ifa, ifp) { 370 #if defined(INET) || defined(INET6) 371 if (ifa->ifa_addr->sa_family == AF_INET || 372 ifa->ifa_addr->sa_family == AF_INET6) { 373 rtinit(ifa, (int)RTM_DELETE, 374 tp->tun_flags & TUN_DSTADDR 375 ? RTF_HOST 376 : 0); 377 } 378 #endif 379 } 380 } 381 } 382 out_nolock: 383 splx(s); 384 return (0); 385 } 386 387 /* 388 * Call at splnet(). 389 */ 390 static void 391 tuninit(struct tun_softc *tp) 392 { 393 struct ifnet *ifp = &tp->tun_if; 394 struct ifaddr *ifa; 395 396 TUNDEBUG("%s: tuninit\n", ifp->if_xname); 397 398 mutex_enter(&tp->tun_lock); 399 ifp->if_flags |= IFF_UP | IFF_RUNNING; 400 401 tp->tun_flags &= ~(TUN_IASET|TUN_DSTADDR); 402 IFADDR_FOREACH(ifa, ifp) { 403 #ifdef INET 404 if (ifa->ifa_addr->sa_family == AF_INET) { 405 struct sockaddr_in *sin; 406 407 sin = satosin(ifa->ifa_addr); 408 if (sin && sin->sin_addr.s_addr) 409 tp->tun_flags |= TUN_IASET; 410 411 if (ifp->if_flags & IFF_POINTOPOINT) { 412 sin = satosin(ifa->ifa_dstaddr); 413 if (sin && sin->sin_addr.s_addr) 414 tp->tun_flags |= TUN_DSTADDR; 415 } 416 } 417 #endif 418 #ifdef INET6 419 if (ifa->ifa_addr->sa_family == AF_INET6) { 420 struct sockaddr_in6 *sin; 421 422 sin = (struct sockaddr_in6 *)ifa->ifa_addr; 423 if (!IN6_IS_ADDR_UNSPECIFIED(&sin->sin6_addr)) 424 tp->tun_flags |= TUN_IASET; 425 426 if (ifp->if_flags & IFF_POINTOPOINT) { 427 sin = (struct sockaddr_in6 *)ifa->ifa_dstaddr; 428 if (sin && 429 !IN6_IS_ADDR_UNSPECIFIED(&sin->sin6_addr)) 430 tp->tun_flags |= TUN_DSTADDR; 431 } else 432 tp->tun_flags &= ~TUN_DSTADDR; 433 } 434 #endif /* INET6 */ 435 } 436 mutex_exit(&tp->tun_lock); 437 } 438 439 /* 440 * Process an ioctl request. 441 */ 442 static int 443 tun_ioctl(struct ifnet *ifp, u_long cmd, void *data) 444 { 445 int error = 0, s; 446 struct tun_softc *tp = (struct tun_softc *)(ifp->if_softc); 447 struct ifreq *ifr = data; 448 449 s = splnet(); 450 451 switch (cmd) { 452 case SIOCINITIFADDR: 453 tuninit(tp); 454 TUNDEBUG("%s: address set\n", ifp->if_xname); 455 break; 456 case SIOCSIFBRDADDR: 457 TUNDEBUG("%s: broadcast address set\n", ifp->if_xname); 458 break; 459 case SIOCSIFMTU: 460 if (ifr->ifr_mtu > TUNMTU || ifr->ifr_mtu < 576) { 461 error = EINVAL; 462 break; 463 } 464 TUNDEBUG("%s: interface mtu set\n", ifp->if_xname); 465 if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET) 466 error = 0; 467 break; 468 case SIOCADDMULTI: 469 case SIOCDELMULTI: 470 if (ifr == NULL) { 471 error = EAFNOSUPPORT; /* XXX */ 472 break; 473 } 474 switch (ifreq_getaddr(cmd, ifr)->sa_family) { 475 #ifdef INET 476 case AF_INET: 477 break; 478 #endif 479 #ifdef INET6 480 case AF_INET6: 481 break; 482 #endif 483 default: 484 error = EAFNOSUPPORT; 485 break; 486 } 487 break; 488 default: 489 error = ifioctl_common(ifp, cmd, data); 490 } 491 492 splx(s); 493 return (error); 494 } 495 496 /* 497 * tun_output - queue packets from higher level ready to put out. 498 */ 499 static int 500 tun_output(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst, 501 struct rtentry *rt) 502 { 503 struct tun_softc *tp = ifp->if_softc; 504 int s; 505 int error; 506 #if defined(INET) || defined(INET6) 507 int mlen; 508 uint32_t *af; 509 #endif 510 ALTQ_DECL(struct altq_pktattr pktattr;) 511 512 s = splnet(); 513 mutex_enter(&tp->tun_lock); 514 TUNDEBUG ("%s: tun_output\n", ifp->if_xname); 515 516 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 517 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, 518 tp->tun_flags); 519 error = EHOSTDOWN; 520 goto out; 521 } 522 523 /* 524 * if the queueing discipline needs packet classification, 525 * do it before prepending link headers. 526 */ 527 IFQ_CLASSIFY(&ifp->if_snd, m0, dst->sa_family, &pktattr); 528 529 bpf_mtap_af(ifp, dst->sa_family, m0); 530 531 switch(dst->sa_family) { 532 #ifdef INET6 533 case AF_INET6: 534 #endif 535 #ifdef INET 536 case AF_INET: 537 #endif 538 #if defined(INET) || defined(INET6) 539 if (tp->tun_flags & TUN_PREPADDR) { 540 /* Simple link-layer header */ 541 M_PREPEND(m0, dst->sa_len, M_DONTWAIT); 542 if (m0 == NULL) { 543 IF_DROP(&ifp->if_snd); 544 error = ENOBUFS; 545 goto out; 546 } 547 bcopy(dst, mtod(m0, char *), dst->sa_len); 548 } 549 550 if (tp->tun_flags & TUN_IFHEAD) { 551 /* Prepend the address family */ 552 M_PREPEND(m0, sizeof(*af), M_DONTWAIT); 553 if (m0 == NULL) { 554 IF_DROP(&ifp->if_snd); 555 error = ENOBUFS; 556 goto out; 557 } 558 af = mtod(m0,uint32_t *); 559 *af = htonl(dst->sa_family); 560 } else { 561 #ifdef INET 562 if (dst->sa_family != AF_INET) 563 #endif 564 { 565 error = EAFNOSUPPORT; 566 goto out; 567 } 568 } 569 /* FALLTHROUGH */ 570 case AF_UNSPEC: 571 IFQ_ENQUEUE(&ifp->if_snd, m0, &pktattr, error); 572 if (error) { 573 ifp->if_collisions++; 574 error = EAFNOSUPPORT; 575 m0 = NULL; 576 goto out; 577 } 578 mlen = m0->m_pkthdr.len; 579 ifp->if_opackets++; 580 ifp->if_obytes += mlen; 581 break; 582 #endif 583 default: 584 error = EAFNOSUPPORT; 585 goto out; 586 } 587 588 if (tp->tun_flags & TUN_RWAIT) { 589 tp->tun_flags &= ~TUN_RWAIT; 590 wakeup((void *)tp); 591 } 592 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 593 softint_schedule(tp->tun_isih); 594 595 selnotify(&tp->tun_rsel, 0, 0); 596 out: 597 mutex_exit(&tp->tun_lock); 598 splx(s); 599 600 if (error && m0) { 601 m_freem(m0); 602 } 603 return 0; 604 } 605 606 static void 607 tun_i_softintr(void *cookie) 608 { 609 struct tun_softc *tp = cookie; 610 611 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 612 fownsignal(tp->tun_pgid, SIGIO, POLL_IN, POLLIN|POLLRDNORM, 613 NULL); 614 } 615 616 static void 617 tun_o_softintr(void *cookie) 618 { 619 struct tun_softc *tp = cookie; 620 621 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 622 fownsignal(tp->tun_pgid, SIGIO, POLL_OUT, POLLOUT|POLLWRNORM, 623 NULL); 624 } 625 626 /* 627 * the cdevsw interface is now pretty minimal. 628 */ 629 int 630 tunioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) 631 { 632 struct tun_softc *tp; 633 int s, error = 0; 634 635 s = splnet(); 636 tp = tun_find_unit(dev); 637 638 /* interface was "destroyed" already */ 639 if (tp == NULL) { 640 error = ENXIO; 641 goto out_nolock; 642 } 643 644 switch (cmd) { 645 case TUNSDEBUG: 646 tundebug = *(int *)data; 647 break; 648 649 case TUNGDEBUG: 650 *(int *)data = tundebug; 651 break; 652 653 case TUNSIFMODE: 654 switch (*(int *)data & (IFF_POINTOPOINT|IFF_BROADCAST)) { 655 case IFF_POINTOPOINT: 656 case IFF_BROADCAST: 657 if (tp->tun_if.if_flags & IFF_UP) { 658 error = EBUSY; 659 goto out; 660 } 661 tp->tun_if.if_flags &= 662 ~(IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST); 663 tp->tun_if.if_flags |= *(int *)data; 664 break; 665 default: 666 error = EINVAL; 667 goto out; 668 } 669 break; 670 671 case TUNSLMODE: 672 if (*(int *)data) { 673 tp->tun_flags |= TUN_PREPADDR; 674 tp->tun_flags &= ~TUN_IFHEAD; 675 } else 676 tp->tun_flags &= ~TUN_PREPADDR; 677 break; 678 679 case TUNSIFHEAD: 680 if (*(int *)data) { 681 tp->tun_flags |= TUN_IFHEAD; 682 tp->tun_flags &= ~TUN_PREPADDR; 683 } else 684 tp->tun_flags &= ~TUN_IFHEAD; 685 break; 686 687 case TUNGIFHEAD: 688 *(int *)data = (tp->tun_flags & TUN_IFHEAD); 689 break; 690 691 case FIONBIO: 692 if (*(int *)data) 693 tp->tun_flags |= TUN_NBIO; 694 else 695 tp->tun_flags &= ~TUN_NBIO; 696 break; 697 698 case FIOASYNC: 699 if (*(int *)data) 700 tp->tun_flags |= TUN_ASYNC; 701 else 702 tp->tun_flags &= ~TUN_ASYNC; 703 break; 704 705 case FIONREAD: 706 if (tp->tun_if.if_snd.ifq_head) 707 *(int *)data = tp->tun_if.if_snd.ifq_head->m_pkthdr.len; 708 else 709 *(int *)data = 0; 710 break; 711 712 case TIOCSPGRP: 713 case FIOSETOWN: 714 error = fsetown(&tp->tun_pgid, cmd, data); 715 break; 716 717 case TIOCGPGRP: 718 case FIOGETOWN: 719 error = fgetown(tp->tun_pgid, cmd, data); 720 break; 721 722 default: 723 error = ENOTTY; 724 } 725 726 out: 727 mutex_exit(&tp->tun_lock); 728 out_nolock: 729 splx(s); 730 return (error); 731 } 732 733 /* 734 * The cdevsw read interface - reads a packet at a time, or at 735 * least as much of a packet as can be read. 736 */ 737 int 738 tunread(dev_t dev, struct uio *uio, int ioflag) 739 { 740 struct tun_softc *tp; 741 struct ifnet *ifp; 742 struct mbuf *m, *m0; 743 int error = 0, len, s, index; 744 745 s = splnet(); 746 tp = tun_find_unit(dev); 747 748 /* interface was "destroyed" already */ 749 if (tp == NULL) { 750 error = ENXIO; 751 goto out_nolock; 752 } 753 754 index = tp->tun_if.if_index; 755 ifp = &tp->tun_if; 756 757 TUNDEBUG ("%s: read\n", ifp->if_xname); 758 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 759 TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, tp->tun_flags); 760 error = EHOSTDOWN; 761 goto out; 762 } 763 764 tp->tun_flags &= ~TUN_RWAIT; 765 766 do { 767 IFQ_DEQUEUE(&ifp->if_snd, m0); 768 if (m0 == 0) { 769 if (tp->tun_flags & TUN_NBIO) { 770 error = EWOULDBLOCK; 771 goto out; 772 } 773 tp->tun_flags |= TUN_RWAIT; 774 if (mtsleep((void *)tp, PZERO|PCATCH|PNORELOCK, 775 "tunread", 0, &tp->tun_lock) != 0) { 776 error = EINTR; 777 goto out_nolock; 778 } else { 779 /* 780 * Maybe the interface was destroyed while 781 * we were sleeping, so let's ensure that 782 * we're looking at the same (valid) tun 783 * interface before looping. 784 */ 785 tp = tun_find_unit(dev); 786 if (tp == NULL) { 787 error = ENXIO; 788 goto out_nolock; 789 } 790 if (tp->tun_if.if_index != index) { 791 error = ENXIO; 792 goto out; 793 } 794 } 795 } 796 } while (m0 == 0); 797 798 mutex_exit(&tp->tun_lock); 799 splx(s); 800 801 /* Copy the mbuf chain */ 802 while (m0 && uio->uio_resid > 0 && error == 0) { 803 len = min(uio->uio_resid, m0->m_len); 804 if (len != 0) 805 error = uiomove(mtod(m0, void *), len, uio); 806 MFREE(m0, m); 807 m0 = m; 808 } 809 810 if (m0) { 811 TUNDEBUG("Dropping mbuf\n"); 812 m_freem(m0); 813 } 814 if (error) 815 ifp->if_ierrors++; 816 817 return (error); 818 819 out: 820 mutex_exit(&tp->tun_lock); 821 out_nolock: 822 splx(s); 823 return (error); 824 } 825 826 /* 827 * the cdevsw write interface - an atomic write is a packet - or else! 828 */ 829 int 830 tunwrite(dev_t dev, struct uio *uio, int ioflag) 831 { 832 struct tun_softc *tp; 833 struct ifnet *ifp; 834 struct mbuf *top, **mp, *m; 835 struct ifqueue *ifq; 836 struct sockaddr dst; 837 int isr, error = 0, s, tlen, mlen; 838 uint32_t family; 839 840 s = splnet(); 841 tp = tun_find_unit(dev); 842 843 /* interface was "destroyed" already */ 844 if (tp == NULL) { 845 error = ENXIO; 846 goto out_nolock; 847 } 848 849 /* Unlock until we've got the data */ 850 mutex_exit(&tp->tun_lock); 851 splx(s); 852 853 ifp = &tp->tun_if; 854 855 TUNDEBUG("%s: tunwrite\n", ifp->if_xname); 856 857 if (tp->tun_flags & TUN_PREPADDR) { 858 if (uio->uio_resid < sizeof(dst)) { 859 error = EIO; 860 goto out0; 861 } 862 error = uiomove((void *)&dst, sizeof(dst), uio); 863 if (dst.sa_len > sizeof(dst)) { 864 /* Duh.. */ 865 char discard; 866 int n = dst.sa_len - sizeof(dst); 867 while (n--) 868 if ((error = uiomove(&discard, 1, uio)) != 0) { 869 goto out0; 870 } 871 } 872 } else if (tp->tun_flags & TUN_IFHEAD) { 873 if (uio->uio_resid < sizeof(family)){ 874 error = EIO; 875 goto out0; 876 } 877 error = uiomove((void *)&family, sizeof(family), uio); 878 dst.sa_family = ntohl(family); 879 } else { 880 #ifdef INET 881 dst.sa_family = AF_INET; 882 #endif 883 } 884 885 if (uio->uio_resid > TUNMTU) { 886 TUNDEBUG("%s: len=%lu!\n", ifp->if_xname, 887 (unsigned long)uio->uio_resid); 888 error = EIO; 889 goto out0; 890 } 891 892 switch (dst.sa_family) { 893 #ifdef INET 894 case AF_INET: 895 ifq = &ipintrq; 896 isr = NETISR_IP; 897 break; 898 #endif 899 #ifdef INET6 900 case AF_INET6: 901 ifq = &ip6intrq; 902 isr = NETISR_IPV6; 903 break; 904 #endif 905 default: 906 error = EAFNOSUPPORT; 907 goto out0; 908 } 909 910 tlen = uio->uio_resid; 911 912 /* get a header mbuf */ 913 MGETHDR(m, M_DONTWAIT, MT_DATA); 914 if (m == NULL) { 915 error = ENOBUFS; 916 goto out0; 917 } 918 mlen = MHLEN; 919 920 top = NULL; 921 mp = ⊤ 922 while (error == 0 && uio->uio_resid > 0) { 923 m->m_len = min(mlen, uio->uio_resid); 924 error = uiomove(mtod(m, void *), m->m_len, uio); 925 *mp = m; 926 mp = &m->m_next; 927 if (error == 0 && uio->uio_resid > 0) { 928 MGET(m, M_DONTWAIT, MT_DATA); 929 if (m == NULL) { 930 error = ENOBUFS; 931 break; 932 } 933 mlen = MLEN; 934 } 935 } 936 if (error) { 937 if (top != NULL) 938 m_freem (top); 939 ifp->if_ierrors++; 940 goto out0; 941 } 942 943 top->m_pkthdr.len = tlen; 944 top->m_pkthdr.rcvif = ifp; 945 946 bpf_mtap_af(ifp, dst.sa_family, top); 947 948 s = splnet(); 949 mutex_enter(&tp->tun_lock); 950 if ((tp->tun_flags & TUN_INITED) == 0) { 951 /* Interface was destroyed */ 952 error = ENXIO; 953 goto out; 954 } 955 if (IF_QFULL(ifq)) { 956 IF_DROP(ifq); 957 ifp->if_collisions++; 958 mutex_exit(&tp->tun_lock); 959 m_freem(top); 960 error = ENOBUFS; 961 goto out_nolock; 962 } 963 964 IF_ENQUEUE(ifq, top); 965 ifp->if_ipackets++; 966 ifp->if_ibytes += tlen; 967 schednetisr(isr); 968 out: 969 mutex_exit(&tp->tun_lock); 970 out_nolock: 971 splx(s); 972 out0: 973 return (error); 974 } 975 976 #ifdef ALTQ 977 /* 978 * Start packet transmission on the interface. 979 * when the interface queue is rate-limited by ALTQ or TBR, 980 * if_start is needed to drain packets from the queue in order 981 * to notify readers when outgoing packets become ready. 982 * 983 * Should be called at splnet. 984 */ 985 static void 986 tunstart(struct ifnet *ifp) 987 { 988 struct tun_softc *tp = ifp->if_softc; 989 990 if (!ALTQ_IS_ENABLED(&ifp->if_snd) && !TBR_IS_ENABLED(&ifp->if_snd)) 991 return; 992 993 mutex_enter(&tp->tun_lock); 994 if (!IF_IS_EMPTY(&ifp->if_snd)) { 995 if (tp->tun_flags & TUN_RWAIT) { 996 tp->tun_flags &= ~TUN_RWAIT; 997 wakeup((void *)tp); 998 } 999 if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid) 1000 softint_schedule(tp->tun_osih); 1001 1002 selnotify(&tp->tun_rsel, 0, 0); 1003 } 1004 mutex_exit(&tp->tun_lock); 1005 } 1006 #endif /* ALTQ */ 1007 /* 1008 * tunpoll - the poll interface, this is only useful on reads 1009 * really. The write detect always returns true, write never blocks 1010 * anyway, it either accepts the packet or drops it. 1011 */ 1012 int 1013 tunpoll(dev_t dev, int events, struct lwp *l) 1014 { 1015 struct tun_softc *tp; 1016 struct ifnet *ifp; 1017 int s, revents = 0; 1018 1019 s = splnet(); 1020 tp = tun_find_unit(dev); 1021 1022 /* interface was "destroyed" already */ 1023 if (tp == NULL) 1024 goto out_nolock; 1025 1026 ifp = &tp->tun_if; 1027 1028 TUNDEBUG("%s: tunpoll\n", ifp->if_xname); 1029 1030 if (events & (POLLIN | POLLRDNORM)) { 1031 if (!IFQ_IS_EMPTY(&ifp->if_snd)) { 1032 TUNDEBUG("%s: tunpoll q=%d\n", ifp->if_xname, 1033 ifp->if_snd.ifq_len); 1034 revents |= events & (POLLIN | POLLRDNORM); 1035 } else { 1036 TUNDEBUG("%s: tunpoll waiting\n", ifp->if_xname); 1037 selrecord(l, &tp->tun_rsel); 1038 } 1039 } 1040 1041 if (events & (POLLOUT | POLLWRNORM)) 1042 revents |= events & (POLLOUT | POLLWRNORM); 1043 1044 mutex_exit(&tp->tun_lock); 1045 out_nolock: 1046 splx(s); 1047 return (revents); 1048 } 1049 1050 static void 1051 filt_tunrdetach(struct knote *kn) 1052 { 1053 struct tun_softc *tp = kn->kn_hook; 1054 int s; 1055 1056 s = splnet(); 1057 SLIST_REMOVE(&tp->tun_rsel.sel_klist, kn, knote, kn_selnext); 1058 splx(s); 1059 } 1060 1061 static int 1062 filt_tunread(struct knote *kn, long hint) 1063 { 1064 struct tun_softc *tp = kn->kn_hook; 1065 struct ifnet *ifp = &tp->tun_if; 1066 struct mbuf *m; 1067 int s; 1068 1069 s = splnet(); 1070 IF_POLL(&ifp->if_snd, m); 1071 if (m == NULL) { 1072 splx(s); 1073 return (0); 1074 } 1075 1076 for (kn->kn_data = 0; m != NULL; m = m->m_next) 1077 kn->kn_data += m->m_len; 1078 1079 splx(s); 1080 return (1); 1081 } 1082 1083 static const struct filterops tunread_filtops = 1084 { 1, NULL, filt_tunrdetach, filt_tunread }; 1085 1086 static const struct filterops tun_seltrue_filtops = 1087 { 1, NULL, filt_tunrdetach, filt_seltrue }; 1088 1089 int 1090 tunkqfilter(dev_t dev, struct knote *kn) 1091 { 1092 struct tun_softc *tp; 1093 struct klist *klist; 1094 int rv = 0, s; 1095 1096 s = splnet(); 1097 tp = tun_find_unit(dev); 1098 if (tp == NULL) 1099 goto out_nolock; 1100 1101 switch (kn->kn_filter) { 1102 case EVFILT_READ: 1103 klist = &tp->tun_rsel.sel_klist; 1104 kn->kn_fop = &tunread_filtops; 1105 break; 1106 1107 case EVFILT_WRITE: 1108 klist = &tp->tun_rsel.sel_klist; 1109 kn->kn_fop = &tun_seltrue_filtops; 1110 break; 1111 1112 default: 1113 rv = EINVAL; 1114 goto out; 1115 } 1116 1117 kn->kn_hook = tp; 1118 1119 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 1120 1121 out: 1122 mutex_exit(&tp->tun_lock); 1123 out_nolock: 1124 splx(s); 1125 return (rv); 1126 } 1127
Indexes created Wed Sep 24 05:09:52 GMT 2025