bsd/net/if_gif.c

   1 /*
   2  * Copyright (c) 2000-2020 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /* $FreeBSD: src/sys/net/if_gif.c,v 1.4.2.6 2001/07/24 19:10:18 brooks Exp $ */
  29 /* $KAME: if_gif.c,v 1.47 2001/05/01 05:28:42 itojun Exp $ */
  30
  31 /*
  32  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
  33  * All rights reserved.
  34  *
  35  * Redistribution and use in source and binary forms, with or without
  36  * modification, are permitted provided that the following conditions
  37  * are met:
  38  * 1. Redistributions of source code must retain the above copyright
  39  *    notice, this list of conditions and the following disclaimer.
  40  * 2. Redistributions in binary form must reproduce the above copyright
  41  *    notice, this list of conditions and the following disclaimer in the
  42  *    documentation and/or other materials provided with the distribution.
  43  * 3. Neither the name of the project nor the names of its contributors
  44  *    may be used to endorse or promote products derived from this software
  45  *    without specific prior written permission.
  46  *
  47  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  48  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  49  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  50  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  51  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  52  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  53  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  54  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  55  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  56  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  57  * SUCH DAMAGE.
  58  */
  59 /*
  60  * NOTICE: This file was modified by SPARTA, Inc. in 2006 to introduce
  61  * support for mandatory and extensible security protections.  This notice
  62  * is included in support of clause 2.2 (b) of the Apple Public License,
  63  * Version 2.0.
  64  */
  65
  66 #include <sys/param.h>
  67 #include <sys/systm.h>
  68 #include <sys/kernel.h>
  69 #include <sys/malloc.h>
  70 #include <sys/mbuf.h>
  71 #include <sys/socket.h>
  72 #include <sys/sockio.h>
  73 #include <sys/errno.h>
  74 #include <sys/time.h>
  75 #include <sys/syslog.h>
  76 #include <sys/protosw.h>
  77 #include <kern/cpu_number.h>
  78 #include <kern/zalloc.h>
  79
  80 #include <net/if.h>
  81 #include <net/if_types.h>
  82 #include <net/route.h>
  83 #include <net/bpf.h>
  84 #include <net/kpi_protocol.h>
  85 #include <net/kpi_interface.h>
  86 #include <net/init.h>
  87
  88 #include <netinet/in.h>
  89 #include <netinet/in_systm.h>
  90 #include <netinet/ip.h>
  91 #if     INET
  92 #include <netinet/in_var.h>
  93 #include <netinet/in_gif.h>
  94 #include <netinet/ip_var.h>
  95 #endif  /* INET */
  96
  97 #if INET6
  98 #include <netinet6/in6_var.h>
  99 #include <netinet/ip6.h>
 100 #include <netinet6/ip6_var.h>
 101 #include <netinet6/in6_gif.h>
 102 #include <netinet6/ip6protosw.h>
 103 #endif /* INET6 */
 104
 105 #include <netinet/ip_encap.h>
 106 #include <net/dlil.h>
 107 #include <net/if_gif.h>
 108
 109 #include <net/net_osdep.h>
 110
 111 #if CONFIG_MACF_NET
 112 #include <security/mac_framework.h>
 113 #endif
 114
 115 #define GIFNAME         "gif"
 116 #define GIFDEV          "if_gif"
 117
 118 #define GIF_MAXUNIT     IF_MAXUNIT
 119 #define GIF_ZONE_MAX_ELEM       MIN(IFNETS_MAX, GIF_MAXUNIT)
 120
 121 /* gif lock variables */
 122 static lck_grp_t        *gif_mtx_grp;
 123 static lck_grp_attr_t   *gif_mtx_grp_attr;
 124 static lck_attr_t       *gif_mtx_attr;
 125 decl_lck_mtx_data(static, gif_mtx_data);
 126 static lck_mtx_t        *gif_mtx = &gif_mtx_data;
 127
 128 TAILQ_HEAD(gifhead, gif_softc) gifs = TAILQ_HEAD_INITIALIZER(gifs);
 129
 130 static int gif_encapcheck(const struct mbuf *, int, int, void *);
 131 static errno_t gif_output(ifnet_t ifp, mbuf_t m);
 132 static errno_t gif_input(ifnet_t ifp, protocol_family_t protocol_family,
 133     mbuf_t m, char *frame_header);
 134 static errno_t gif_ioctl(ifnet_t ifp, u_long cmd, void *data);
 135
 136 static int ngif = 0;            /* number of interfaces */
 137
 138 #if INET
 139 static struct protosw in_gif_protosw =
 140 {
 141         .pr_type =              SOCK_RAW,
 142         .pr_protocol =          0, /* IPPROTO_IPV[46] */
 143         .pr_flags =             PR_ATOMIC | PR_ADDR,
 144         .pr_input =             in_gif_input,
 145         .pr_usrreqs =           &rip_usrreqs,
 146         .pr_unlock =            rip_unlock,
 147 };
 148 #endif
 149 #if INET6
 150 static struct ip6protosw in6_gif_protosw =
 151 {
 152         .pr_type =              SOCK_RAW,
 153         .pr_protocol =          0, /* IPPROTO_IPV[46] */
 154         .pr_flags =             PR_ATOMIC | PR_ADDR,
 155         .pr_input =             in6_gif_input,
 156         .pr_usrreqs =           &rip6_usrreqs,
 157         .pr_unlock =            rip_unlock,
 158 };
 159 #endif
 160
 161 static int gif_remove(struct ifnet *);
 162 static int gif_clone_create(struct if_clone *, uint32_t, void *);
 163 static int gif_clone_destroy(struct ifnet *);
 164 static void gif_delete_tunnel(struct gif_softc *);
 165 static void gif_detach(struct ifnet *);
 166
 167 static struct if_clone gif_cloner =
 168     IF_CLONE_INITIALIZER(GIFNAME, gif_clone_create, gif_clone_destroy,
 169     0, GIF_MAXUNIT, GIF_ZONE_MAX_ELEM, sizeof(struct gif_softc));
 170 /*
 171  * Theory of operation: initially, one gif interface is created.
 172  * Any time a gif interface is configured, if there are no other
 173  * unconfigured gif interfaces, a new gif interface is created.
 174  * BSD uses the clone mechanism to dynamically create more
 175  * gif interfaces.
 176  *
 177  * We have some extra glue to support DLIL.
 178  */
 179
 180 /* GIF interface module support */
 181 static int
 182 gif_demux(
 183         ifnet_t ifp,
 184         __unused mbuf_t m,
 185         __unused char *frame_header,
 186         protocol_family_t *protocol_family)
 187 {
 188         struct gif_softc *sc = ifnet_softc(ifp);
 189
 190         GIF_LOCK(sc);
 191         /* Only one protocol may be attached to a gif interface. */
 192         *protocol_family = sc->gif_proto;
 193         GIF_UNLOCK(sc);
 194
 195         return 0;
 196 }
 197
 198 static errno_t
 199 gif_add_proto(
 200         ifnet_t ifp,
 201         protocol_family_t protocol_family,
 202         __unused const struct ifnet_demux_desc *demux_array,
 203         __unused u_int32_t demux_count)
 204 {
 205         /* Only one protocol may be attached at a time */
 206         struct gif_softc *sc = ifnet_softc(ifp);
 207
 208         GIF_LOCK(sc);
 209         if (sc->gif_proto != 0) {
 210                 printf("gif_add_proto: request add_proto for gif%d\n",
 211                     ifnet_unit(ifp));
 212         }
 213
 214         sc->gif_proto = protocol_family;
 215         GIF_UNLOCK(sc);
 216
 217         return 0;
 218 }
 219
 220 static errno_t
 221 gif_del_proto(
 222         ifnet_t ifp,
 223         protocol_family_t protocol_family)
 224 {
 225         struct gif_softc *sc = ifnet_softc(ifp);
 226
 227         GIF_LOCK(sc);
 228         if (sc->gif_proto == protocol_family) {
 229                 sc->gif_proto = 0;
 230         }
 231         GIF_UNLOCK(sc);
 232
 233         return 0;
 234 }
 235
 236 /* Glue code to attach inet to a gif interface through DLIL */
 237 static errno_t
 238 gif_attach_proto_family(
 239         ifnet_t ifp,
 240         protocol_family_t protocol_family)
 241 {
 242         struct ifnet_attach_proto_param reg;
 243         errno_t stat;
 244
 245         bzero(&reg, sizeof(reg));
 246         reg.input = gif_input;
 247
 248         stat = ifnet_attach_protocol(ifp, protocol_family, &reg);
 249         if (stat && stat != EEXIST) {
 250                 printf("gif_attach_proto_family can't attach interface  \
 251                     fam=%d\n", protocol_family);
 252         }
 253
 254         return stat;
 255 }
 256
 257 /* Function to setup the first gif interface */
 258 void
 259 gif_init(void)
 260 {
 261         errno_t result;
 262
 263         /* Initialize the list of interfaces */
 264         TAILQ_INIT(&gifs);
 265
 266         /* Initialize the gif global lock */
 267         gif_mtx_grp_attr = lck_grp_attr_alloc_init();
 268         gif_mtx_grp = lck_grp_alloc_init("gif", gif_mtx_grp_attr);
 269         gif_mtx_attr = lck_attr_alloc_init();
 270         lck_mtx_init(gif_mtx, gif_mtx_grp, gif_mtx_attr);
 271
 272         /* Register protocol registration functions */
 273         result = proto_register_plumber(PF_INET, APPLE_IF_FAM_GIF,
 274             gif_attach_proto_family, NULL);
 275         if (result != 0) {
 276                 printf("proto_register_plumber failed for AF_INET error=%d\n",
 277                     result);
 278         }
 279
 280         result = proto_register_plumber(PF_INET6, APPLE_IF_FAM_GIF,
 281             gif_attach_proto_family, NULL);
 282         if (result != 0) {
 283                 printf("proto_register_plumber failed for AF_INET6 error=%d\n",
 284                     result);
 285         }
 286
 287         result = if_clone_attach(&gif_cloner);
 288         if (result != 0) {
 289                 panic("%s: if_clone_attach() failed, error %d\n", __func__, result);
 290         }
 291
 292         gif_clone_create(&gif_cloner, 0, NULL);
 293 }
 294
 295 static errno_t
 296 gif_set_bpf_tap(
 297         ifnet_t ifp,
 298         bpf_tap_mode mode,
 299         bpf_packet_func callback)
 300 {
 301         struct gif_softc *sc = ifnet_softc(ifp);
 302
 303         GIF_LOCK(sc);
 304         sc->tap_mode = mode;
 305         sc->tap_callback = callback;
 306         GIF_UNLOCK(sc);
 307
 308         return 0;
 309 }
 310
 311 static void
 312 gif_detach(struct ifnet *ifp)
 313 {
 314         struct gif_softc *sc = ifp->if_softc;
 315         lck_mtx_destroy(&sc->gif_lock, gif_mtx_grp);
 316         if_clone_softc_deallocate(&gif_cloner, sc);
 317         ifp->if_softc = NULL;
 318         (void) ifnet_release(ifp);
 319 }
 320
 321 static int
 322 gif_clone_create(struct if_clone *ifc, uint32_t unit, __unused void *params)
 323 {
 324         struct gif_softc *sc = NULL;
 325         struct ifnet_init_eparams gif_init_params;
 326         errno_t error = 0;
 327
 328         lck_mtx_lock(gif_mtx);
 329
 330         /* Can't create more than GIF_MAXUNIT */
 331         if (ngif >= GIF_MAXUNIT) {
 332                 error = ENXIO;
 333                 goto done;
 334         }
 335
 336         sc = if_clone_softc_allocate(&gif_cloner);
 337         if (sc == NULL) {
 338                 log(LOG_ERR, "gif_clone_create: failed to allocate gif%d\n",
 339                     unit);
 340                 error = ENOBUFS;
 341                 goto done;
 342         }
 343
 344         /* use the interface name as the unique id for ifp recycle */
 345         snprintf(sc->gif_ifname, sizeof(sc->gif_ifname), "%s%d",
 346             ifc->ifc_name, unit);
 347
 348         lck_mtx_init(&sc->gif_lock, gif_mtx_grp, gif_mtx_attr);
 349
 350         bzero(&gif_init_params, sizeof(gif_init_params));
 351         gif_init_params.ver = IFNET_INIT_CURRENT_VERSION;
 352         gif_init_params.len = sizeof(gif_init_params);
 353         gif_init_params.flags = IFNET_INIT_LEGACY;
 354         gif_init_params.uniqueid = sc->gif_ifname;
 355         gif_init_params.uniqueid_len = strlen(sc->gif_ifname);
 356         gif_init_params.name = GIFNAME;
 357         gif_init_params.unit = unit;
 358         gif_init_params.type = IFT_GIF;
 359         gif_init_params.family = IFNET_FAMILY_GIF;
 360         gif_init_params.output = gif_output;
 361         gif_init_params.demux = gif_demux;
 362         gif_init_params.add_proto = gif_add_proto;
 363         gif_init_params.del_proto = gif_del_proto;
 364         gif_init_params.softc = sc;
 365         gif_init_params.ioctl = gif_ioctl;
 366         gif_init_params.set_bpf_tap = gif_set_bpf_tap;
 367         gif_init_params.detach = gif_detach;
 368
 369         error = ifnet_allocate_extended(&gif_init_params, &sc->gif_if);
 370         if (error != 0) {
 371                 printf("gif_clone_create, ifnet_allocate failed - %d\n", error);
 372                 if_clone_softc_deallocate(&gif_cloner, sc);
 373                 error = ENOBUFS;
 374                 goto done;
 375         }
 376
 377         sc->encap_cookie4 = sc->encap_cookie6 = NULL;
 378 #if INET
 379         sc->encap_cookie4 = encap_attach_func(AF_INET, -1,
 380             gif_encapcheck, &in_gif_protosw, sc);
 381         if (sc->encap_cookie4 == NULL) {
 382                 printf("%s: unable to attach encap4\n", if_name(sc->gif_if));
 383                 ifnet_release(sc->gif_if);
 384                 if_clone_softc_deallocate(&gif_cloner, sc);
 385                 error = ENOBUFS;
 386                 goto done;
 387         }
 388 #endif
 389 #if INET6
 390         sc->encap_cookie6 = encap_attach_func(AF_INET6, -1,
 391             gif_encapcheck, (struct protosw *)&in6_gif_protosw, sc);
 392         if (sc->encap_cookie6 == NULL) {
 393                 if (sc->encap_cookie4) {
 394                         encap_detach(sc->encap_cookie4);
 395                         sc->encap_cookie4 = NULL;
 396                 }
 397                 printf("%s: unable to attach encap6\n", if_name(sc->gif_if));
 398                 ifnet_release(sc->gif_if);
 399                 if_clone_softc_deallocate(&gif_cloner, sc);
 400                 error = ENOBUFS;
 401                 goto done;
 402         }
 403 #endif
 404         sc->gif_called = 0;
 405         ifnet_set_mtu(sc->gif_if, GIF_MTU);
 406         ifnet_set_flags(sc->gif_if, IFF_POINTOPOINT | IFF_MULTICAST, 0xffff);
 407 #if 0
 408         /* turn off ingress filter */
 409         sc->gif_if.if_flags  |= IFF_LINK2;
 410 #endif
 411         sc->gif_flags |= IFGIF_DETACHING;
 412         error = ifnet_attach(sc->gif_if, NULL);
 413         if (error != 0) {
 414                 printf("gif_clone_create - ifnet_attach failed - %d\n", error);
 415                 ifnet_release(sc->gif_if);
 416                 if (sc->encap_cookie4) {
 417                         encap_detach(sc->encap_cookie4);
 418                         sc->encap_cookie4 = NULL;
 419                 }
 420                 if (sc->encap_cookie6) {
 421                         encap_detach(sc->encap_cookie6);
 422                         sc->encap_cookie6 = NULL;
 423                 }
 424                 if_clone_softc_deallocate(&gif_cloner, sc);
 425                 goto done;
 426         }
 427 #if CONFIG_MACF_NET
 428         mac_ifnet_label_init(&sc->gif_if);
 429 #endif
 430         bpfattach(sc->gif_if, DLT_NULL, sizeof(u_int));
 431         sc->gif_flags &= ~IFGIF_DETACHING;
 432         TAILQ_INSERT_TAIL(&gifs, sc, gif_link);
 433         ngif++;
 434 done:
 435         lck_mtx_unlock(gif_mtx);
 436
 437         return error;
 438 }
 439
 440 static int
 441 gif_remove(struct ifnet *ifp)
 442 {
 443         int error = 0;
 444         struct gif_softc *sc = NULL;
 445         const struct encaptab *encap_cookie4 = NULL;
 446         const struct encaptab *encap_cookie6 = NULL;
 447
 448         lck_mtx_lock(gif_mtx);
 449         sc = ifp->if_softc;
 450
 451         if (sc == NULL) {
 452                 error = EINVAL;
 453                 goto done;
 454         }
 455
 456         GIF_LOCK(sc);
 457         if (sc->gif_flags & IFGIF_DETACHING) {
 458                 error = EINVAL;
 459                 goto done;
 460         }
 461
 462         sc->gif_flags |= IFGIF_DETACHING;
 463         TAILQ_REMOVE(&gifs, sc, gif_link);
 464         ngif--;
 465
 466         gif_delete_tunnel(sc);
 467 #ifdef INET6
 468         encap_cookie6 = sc->encap_cookie6;
 469 #endif
 470 #ifdef INET
 471         encap_cookie4 = sc->encap_cookie4;
 472 #endif
 473 done:
 474         if (sc != NULL) {
 475                 GIF_UNLOCK(sc);
 476         }
 477         lck_mtx_unlock(gif_mtx);
 478
 479         if (encap_cookie6 != NULL) {
 480                 error = encap_detach(encap_cookie6);
 481                 KASSERT(error == 0, ("gif_clone_destroy: Unexpected "
 482                     "error detaching encap_cookie6"));
 483         }
 484
 485         if (encap_cookie4 != NULL) {
 486                 error = encap_detach(encap_cookie4);
 487                 KASSERT(error == 0, ("gif_clone_destroy: Unexpected "
 488                     "error detaching encap_cookie4"));
 489         }
 490
 491         return error;
 492 }
 493
 494 static int
 495 gif_clone_destroy(struct ifnet *ifp)
 496 {
 497         int error = 0;
 498
 499         error = gif_remove(ifp);
 500         if (error != 0) {
 501                 printf("gif_clone_destroy: gif remove failed %d\n", error);
 502                 return error;
 503         }
 504
 505         error = ifnet_set_flags(ifp, 0, IFF_UP);
 506         if (error != 0) {
 507                 printf("gif_clone_destroy: ifnet_set_flags failed %d\n", error);
 508         }
 509
 510         error = ifnet_detach(ifp);
 511         if (error != 0) {
 512                 panic("gif_clone_destroy: ifnet_detach(%p) failed %d\n", ifp,
 513                     error);
 514         }
 515         return 0;
 516 }
 517
 518 static int
 519 gif_encapcheck(
 520         const struct mbuf *m,
 521         int off,
 522         int proto,
 523         void *arg)
 524 {
 525         int error = 0;
 526         struct ip ip;
 527         struct gif_softc *sc;
 528
 529         sc = (struct gif_softc *)arg;
 530         if (sc == NULL) {
 531                 return error;
 532         }
 533
 534         GIF_LOCK(sc);
 535         if ((ifnet_flags(sc->gif_if) & IFF_UP) == 0) {
 536                 goto done;
 537         }
 538
 539         /* no physical address */
 540         if (!sc->gif_psrc || !sc->gif_pdst) {
 541                 goto done;
 542         }
 543
 544         switch (proto) {
 545 #if INET
 546         case IPPROTO_IPV4:
 547                 break;
 548 #endif
 549 #if INET6
 550         case IPPROTO_IPV6:
 551                 break;
 552 #endif
 553         default:
 554                 goto done;
 555         }
 556
 557         mbuf_copydata((struct mbuf *)(size_t)m, 0, sizeof(ip), &ip);
 558
 559         switch (ip.ip_v) {
 560 #if INET
 561         case 4:
 562                 if (sc->gif_psrc->sa_family != AF_INET ||
 563                     sc->gif_pdst->sa_family != AF_INET) {
 564                         goto done;
 565                 }
 566                 error = gif_encapcheck4(m, off, proto, arg);
 567 #endif
 568 #if INET6
 569         case 6:
 570                 if (sc->gif_psrc->sa_family != AF_INET6 ||
 571                     sc->gif_pdst->sa_family != AF_INET6) {
 572                         goto done;
 573                 }
 574                 error = gif_encapcheck6(m, off, proto, arg);
 575 #endif
 576         default:
 577                 goto done;
 578         }
 579 done:
 580         GIF_UNLOCK(sc);
 581         return error;
 582 }
 583
 584 static errno_t
 585 gif_output(
 586         ifnet_t ifp,
 587         mbuf_t m)
 588 {
 589         struct gif_softc *sc = ifnet_softc(ifp);
 590         struct sockaddr *gif_psrc;
 591         struct sockaddr *gif_pdst;
 592         int error = 0;
 593
 594         GIF_LOCK(sc);
 595         gif_psrc = sc->gif_psrc;
 596         gif_pdst = sc->gif_pdst;
 597         GIF_UNLOCK(sc);
 598
 599         /*
 600          * max_gif_nesting check used to live here. It doesn't anymore
 601          * because there is no guaruntee that we won't be called
 602          * concurrently from more than one thread.
 603          */
 604         m->m_flags &= ~(M_BCAST | M_MCAST);
 605         if (!(ifnet_flags(ifp) & IFF_UP) ||
 606             gif_psrc == NULL || gif_pdst == NULL) {
 607                 ifnet_touch_lastchange(ifp);
 608                 m_freem(m);     /* free it here not in dlil_output */
 609                 error = ENETDOWN;
 610                 goto end;
 611         }
 612
 613         bpf_tap_out(ifp, 0, m, &sc->gif_proto, sizeof(sc->gif_proto));
 614
 615         GIF_LOCK(sc);
 616
 617         /* inner AF-specific encapsulation */
 618
 619         /* XXX should we check if our outer source is legal? */
 620
 621         /*
 622          * Save the length as m may be free by the output functions
 623          * as they call m_pullup
 624          */
 625         u_int32_t bytes_out = m->m_pkthdr.len;
 626
 627         /* dispatch to output logic based on outer AF */
 628         switch (sc->gif_psrc->sa_family) {
 629 #if INET
 630         case AF_INET:
 631                 error = in_gif_output(ifp, sc->gif_proto, m, NULL);
 632                 break;
 633 #endif
 634 #if INET6
 635         case AF_INET6:
 636                 error = in6_gif_output(ifp, sc->gif_proto, m, NULL);
 637                 break;
 638 #endif
 639         default:
 640                 error = ENETDOWN;
 641                 break;
 642         }
 643
 644         GIF_UNLOCK(sc);
 645 end:
 646         if (error) {
 647                 /* the mbuf was freed either by in_gif_output or in here */
 648                 ifnet_stat_increment_out(ifp, 0, 0, 1);
 649         } else {
 650                 ifnet_stat_increment_out(ifp, 1, bytes_out, 0);
 651         }
 652         if (error == 0) {
 653                 error = EJUSTRETURN; /* if no error, packet got sent already */
 654         }
 655         return error;
 656 }
 657
 658 /*
 659  * gif_input is the input handler for IP and IPv6 attached to gif
 660  */
 661 static errno_t
 662 gif_input(
 663         ifnet_t ifp,
 664         protocol_family_t protocol_family,
 665         mbuf_t m,
 666         __unused char *frame_header)
 667 {
 668         struct gif_softc *sc = ifnet_softc(ifp);
 669
 670         bpf_tap_in(ifp, 0, m, &sc->gif_proto, sizeof(sc->gif_proto));
 671
 672         /*
 673          * Put the packet to the network layer input queue according to the
 674          * specified address family.
 675          * Note: older versions of gif_input directly called network layer
 676          * input functions, e.g. ip6_input, here. We changed the policy to
 677          * prevent too many recursive calls of such input functions, which
 678          * might cause kernel panic. But the change may introduce another
 679          * problem; if the input queue is full, packets are discarded.
 680          * We believed it rarely occurs and changed the policy. If we find
 681          * it occurs more times than we thought, we may change the policy
 682          * again.
 683          */
 684         int32_t pktlen = m->m_pkthdr.len;
 685         if (proto_input(protocol_family, m) != 0) {
 686                 ifnet_stat_increment_in(ifp, 0, 0, 1);
 687                 m_freem(m);
 688         } else {
 689                 ifnet_stat_increment_in(ifp, 1, pktlen, 0);
 690         }
 691
 692         return 0;
 693 }
 694
 695 /* XXX how should we handle IPv6 scope on SIOC[GS]IFPHYADDR? */
 696 static errno_t
 697 gif_ioctl(
 698         ifnet_t                 ifp,
 699         u_long                  cmd,
 700         void                    *data)
 701 {
 702         struct gif_softc *sc  = ifnet_softc(ifp);
 703         struct ifreq *ifr = (struct ifreq *)data;
 704         int error = 0, size;
 705         struct sockaddr *dst = NULL, *src = NULL;
 706         struct sockaddr *sa;
 707         struct ifnet *ifp2;
 708         struct gif_softc *sc2;
 709
 710         switch (cmd) {
 711         case SIOCSIFADDR:
 712                 break;
 713
 714         case SIOCSIFDSTADDR:
 715                 break;
 716
 717         case SIOCADDMULTI:
 718         case SIOCDELMULTI:
 719                 break;
 720
 721 #ifdef  SIOCSIFMTU /* xxx */
 722         case SIOCGIFMTU:
 723                 break;
 724
 725         case SIOCSIFMTU:
 726         {
 727                 u_int32_t mtu;
 728                 mtu = ifr->ifr_mtu;
 729                 if (mtu < GIF_MTU_MIN || mtu > GIF_MTU_MAX) {
 730                         return EINVAL;
 731                 }
 732                 ifnet_set_mtu(ifp, mtu);
 733         }
 734         break;
 735 #endif /* SIOCSIFMTU */
 736
 737         case SIOCSIFPHYADDR:
 738 #if INET6
 739         case SIOCSIFPHYADDR_IN6_32:
 740         case SIOCSIFPHYADDR_IN6_64:
 741 #endif /* INET6 */
 742                 switch (cmd) {
 743 #if INET
 744                 case SIOCSIFPHYADDR:
 745                         src = (struct sockaddr *)
 746                             &(((struct in_aliasreq *)data)->ifra_addr);
 747                         dst = (struct sockaddr *)
 748                             &(((struct in_aliasreq *)data)->ifra_dstaddr);
 749                         break;
 750 #endif
 751 #if INET6
 752                 case SIOCSIFPHYADDR_IN6_32: {
 753                         struct in6_aliasreq_32 *ifra_32 =
 754                             (struct in6_aliasreq_32 *)data;
 755
 756                         src = (struct sockaddr *)&ifra_32->ifra_addr;
 757                         dst = (struct sockaddr *)&ifra_32->ifra_dstaddr;
 758                         break;
 759                 }
 760
 761                 case SIOCSIFPHYADDR_IN6_64: {
 762                         struct in6_aliasreq_64 *ifra_64 =
 763                             (struct in6_aliasreq_64 *)data;
 764
 765                         src = (struct sockaddr *)&ifra_64->ifra_addr;
 766                         dst = (struct sockaddr *)&ifra_64->ifra_dstaddr;
 767                         break;
 768                 }
 769 #endif
 770                 }
 771
 772                 /* sa_family must be equal */
 773                 if (src->sa_family != dst->sa_family) {
 774                         return EINVAL;
 775                 }
 776
 777                 /* validate sa_len */
 778                 switch (src->sa_family) {
 779 #if INET
 780                 case AF_INET:
 781                         if (src->sa_len != sizeof(struct sockaddr_in)) {
 782                                 return EINVAL;
 783                         }
 784                         break;
 785 #endif
 786 #if INET6
 787                 case AF_INET6:
 788                         if (src->sa_len != sizeof(struct sockaddr_in6)) {
 789                                 return EINVAL;
 790                         }
 791                         break;
 792 #endif
 793                 default:
 794                         return EAFNOSUPPORT;
 795                 }
 796                 switch (dst->sa_family) {
 797 #if INET
 798                 case AF_INET:
 799                         if (dst->sa_len != sizeof(struct sockaddr_in)) {
 800                                 return EINVAL;
 801                         }
 802                         break;
 803 #endif
 804 #if INET6
 805                 case AF_INET6:
 806                         if (dst->sa_len != sizeof(struct sockaddr_in6)) {
 807                                 return EINVAL;
 808                         }
 809                         break;
 810 #endif
 811                 default:
 812                         return EAFNOSUPPORT;
 813                 }
 814
 815                 /* check sa_family looks sane for the cmd */
 816                 switch (cmd) {
 817                 case SIOCSIFPHYADDR:
 818                         if (src->sa_family == AF_INET) {
 819                                 break;
 820                         }
 821                         return EAFNOSUPPORT;
 822 #if INET6
 823                 case SIOCSIFPHYADDR_IN6_32:
 824                 case SIOCSIFPHYADDR_IN6_64:
 825                         if (src->sa_family == AF_INET6) {
 826                                 break;
 827                         }
 828                         return EAFNOSUPPORT;
 829 #endif /* INET6 */
 830                 }
 831
 832 #define GIF_ORDERED_LOCK(sc, sc2)       \
 833         if (sc < sc2) {                 \
 834                 GIF_LOCK(sc);           \
 835                 GIF_LOCK(sc2);          \
 836         } else {                        \
 837                 GIF_LOCK(sc2);          \
 838                 GIF_LOCK(sc);           \
 839         }
 840
 841 #define GIF_ORDERED_UNLOCK(sc, sc2)     \
 842         if (sc > sc2) {                 \
 843                 GIF_UNLOCK(sc);         \
 844                 GIF_UNLOCK(sc2);        \
 845         } else {                        \
 846                 GIF_UNLOCK(sc2);        \
 847                 GIF_UNLOCK(sc);         \
 848         }
 849
 850                 ifnet_head_lock_shared();
 851                 TAILQ_FOREACH(ifp2, &ifnet_head, if_link) {
 852                         if (strcmp(ifnet_name(ifp2), GIFNAME) != 0) {
 853                                 continue;
 854                         }
 855                         sc2 = ifnet_softc(ifp2);
 856                         if (sc2 == sc) {
 857                                 continue;
 858                         }
 859                         /* lock sc and sc2 in increasing order of ifnet index */
 860                         GIF_ORDERED_LOCK(sc, sc2);
 861                         if (!sc2->gif_pdst || !sc2->gif_psrc) {
 862                                 GIF_ORDERED_UNLOCK(sc, sc2);
 863                                 continue;
 864                         }
 865                         if (sc2->gif_pdst->sa_family != dst->sa_family ||
 866                             sc2->gif_pdst->sa_len != dst->sa_len ||
 867                             sc2->gif_psrc->sa_family != src->sa_family ||
 868                             sc2->gif_psrc->sa_len != src->sa_len) {
 869                                 GIF_ORDERED_UNLOCK(sc, sc2);
 870                                 continue;
 871                         }
 872 #ifndef XBONEHACK
 873                         /* can't configure same pair of address onto two gifs */
 874                         if (bcmp(sc2->gif_pdst, dst, dst->sa_len) == 0 &&
 875                             bcmp(sc2->gif_psrc, src, src->sa_len) == 0) {
 876                                 GIF_ORDERED_UNLOCK(sc, sc2);
 877                                 error = EADDRNOTAVAIL;
 878                                 ifnet_head_done();
 879                                 goto bad;
 880                         }
 881 #endif
 882
 883                         /* can't configure multiple multi-dest interfaces */
 884 #define multidest(x) \
 885         (((struct sockaddr_in *)(void *)(x))->sin_addr.s_addr == INADDR_ANY)
 886 #if INET6
 887 #define multidest6(x) \
 888         (IN6_IS_ADDR_UNSPECIFIED(&((struct sockaddr_in6 *)      \
 889             (void *)(x))->sin6_addr))
 890 #endif
 891                         if (dst->sa_family == AF_INET &&
 892                             multidest(dst) && multidest(sc2->gif_pdst)) {
 893                                 GIF_ORDERED_UNLOCK(sc, sc2);
 894                                 error = EADDRNOTAVAIL;
 895                                 ifnet_head_done();
 896                                 goto bad;
 897                         }
 898 #if INET6
 899                         if (dst->sa_family == AF_INET6 &&
 900                             multidest6(dst) && multidest6(sc2->gif_pdst)) {
 901                                 GIF_ORDERED_UNLOCK(sc, sc2);
 902                                 error = EADDRNOTAVAIL;
 903                                 ifnet_head_done();
 904                                 goto bad;
 905                         }
 906 #endif
 907                         GIF_ORDERED_UNLOCK(sc, sc2);
 908                 }
 909                 ifnet_head_done();
 910
 911                 GIF_LOCK(sc);
 912                 if (sc->gif_psrc) {
 913                         FREE(sc->gif_psrc, M_IFADDR);
 914                 }
 915                 sa = (struct sockaddr *)_MALLOC(src->sa_len, M_IFADDR,
 916                     M_WAITOK);
 917                 if (sa == NULL) {
 918                         GIF_UNLOCK(sc);
 919                         return ENOBUFS;
 920                 }
 921                 bcopy((caddr_t)src, (caddr_t)sa, src->sa_len);
 922                 sc->gif_psrc = sa;
 923
 924                 if (sc->gif_pdst) {
 925                         FREE(sc->gif_pdst, M_IFADDR);
 926                 }
 927                 sa = (struct sockaddr *)_MALLOC(dst->sa_len, M_IFADDR,
 928                     M_WAITOK);
 929                 if (sa == NULL) {
 930                         GIF_UNLOCK(sc);
 931                         return ENOBUFS;
 932                 }
 933                 bcopy((caddr_t)dst, (caddr_t)sa, dst->sa_len);
 934                 sc->gif_pdst = sa;
 935                 GIF_UNLOCK(sc);
 936
 937                 ifnet_set_flags(ifp, IFF_RUNNING | IFF_UP, IFF_RUNNING |
 938                     IFF_UP);
 939
 940                 error = 0;
 941                 break;
 942
 943 #ifdef SIOCDIFPHYADDR
 944         case SIOCDIFPHYADDR:
 945                 GIF_LOCK(sc);
 946                 if (sc->gif_psrc) {
 947                         FREE(sc->gif_psrc, M_IFADDR);
 948                         sc->gif_psrc = NULL;
 949                 }
 950                 if (sc->gif_pdst) {
 951                         FREE(sc->gif_pdst, M_IFADDR);
 952                         sc->gif_pdst = NULL;
 953                 }
 954                 GIF_UNLOCK(sc);
 955                 /* change the IFF_{UP, RUNNING} flag as well? */
 956                 break;
 957 #endif
 958
 959         case SIOCGIFPSRCADDR:
 960 #if INET6
 961         case SIOCGIFPSRCADDR_IN6:
 962 #endif /* INET6 */
 963                 GIF_LOCK(sc);
 964                 if (sc->gif_psrc == NULL) {
 965                         GIF_UNLOCK(sc);
 966                         error = EADDRNOTAVAIL;
 967                         goto bad;
 968                 }
 969                 src = sc->gif_psrc;
 970                 switch (cmd) {
 971 #if INET
 972                 case SIOCGIFPSRCADDR:
 973                         dst = &ifr->ifr_addr;
 974                         size = sizeof(ifr->ifr_addr);
 975                         break;
 976 #endif /* INET */
 977 #if INET6
 978                 case SIOCGIFPSRCADDR_IN6:
 979                         dst = (struct sockaddr *)
 980                             &(((struct in6_ifreq *)data)->ifr_addr);
 981                         size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
 982                         break;
 983 #endif /* INET6 */
 984                 default:
 985                         GIF_UNLOCK(sc);
 986                         error = EADDRNOTAVAIL;
 987                         goto bad;
 988                 }
 989                 if (src->sa_len > size) {
 990                         GIF_UNLOCK(sc);
 991                         return EINVAL;
 992                 }
 993                 bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
 994                 GIF_UNLOCK(sc);
 995                 break;
 996
 997         case SIOCGIFPDSTADDR:
 998 #if INET6
 999         case SIOCGIFPDSTADDR_IN6:
1000 #endif /* INET6 */
1001                 GIF_LOCK(sc);
1002                 if (sc->gif_pdst == NULL) {
1003                         GIF_UNLOCK(sc);
1004                         error = EADDRNOTAVAIL;
1005                         goto bad;
1006                 }
1007                 src = sc->gif_pdst;
1008                 switch (cmd) {
1009 #if INET
1010                 case SIOCGIFPDSTADDR:
1011                         dst = &ifr->ifr_addr;
1012                         size = sizeof(ifr->ifr_addr);
1013                         break;
1014 #endif /* INET */
1015 #if INET6
1016                 case SIOCGIFPDSTADDR_IN6:
1017                         dst = (struct sockaddr *)
1018                             &(((struct in6_ifreq *)data)->ifr_addr);
1019                         size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
1020                         break;
1021 #endif /* INET6 */
1022                 default:
1023                         error = EADDRNOTAVAIL;
1024                         GIF_UNLOCK(sc);
1025                         goto bad;
1026                 }
1027                 if (src->sa_len > size) {
1028                         GIF_UNLOCK(sc);
1029                         return EINVAL;
1030                 }
1031                 bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
1032                 GIF_UNLOCK(sc);
1033                 break;
1034
1035         case SIOCSIFFLAGS:
1036                 /* if_ioctl() takes care of it */
1037                 break;
1038
1039         default:
1040                 error = EOPNOTSUPP;
1041                 break;
1042         }
1043 bad:
1044         return error;
1045 }
1046
1047 static void
1048 gif_delete_tunnel(struct gif_softc *sc)
1049 {
1050         GIF_LOCK_ASSERT(sc);
1051         if (sc->gif_psrc) {
1052                 FREE(sc->gif_psrc, M_IFADDR);
1053                 sc->gif_psrc = NULL;
1054         }
1055         if (sc->gif_pdst) {
1056                 FREE(sc->gif_pdst, M_IFADDR);
1057                 sc->gif_pdst = NULL;
1058         }
1059         ROUTE_RELEASE(&sc->gif_ro);
1060         /* change the IFF_UP flag as well? */
1061 }