bsd/net/iptap.c

   1 /*
   2  * Copyright (c) 1999-2013 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
  29 #include <kern/locks.h>
  30
  31 #include <sys/types.h>
  32 #include <sys/kernel_types.h>
  33 #include <sys/kauth.h>
  34 #include <sys/socket.h>
  35 #include <sys/socketvar.h>
  36 #include <sys/sockio.h>
  37 #include <sys/sysctl.h>
  38 #include <sys/proc.h>
  39
  40 #include <net/if.h>
  41 #include <net/if_var.h>
  42 #include <net/if_types.h>
  43 #include <net/bpf.h>
  44 #include <net/net_osdep.h>
  45 #include <net/pktap.h>
  46 #include <net/iptap.h>
  47
  48 #include <netinet/in_pcb.h>
  49 #include <netinet/tcp.h>
  50 #include <netinet/tcp_var.h>
  51 #define _IP_VHL
  52 #include <netinet/ip.h>
  53 #include <netinet/ip_var.h>
  54 #include <netinet/udp.h>
  55 #include <netinet/udp_var.h>
  56
  57 #include <netinet/ip6.h>
  58 #include <netinet6/in6_pcb.h>
  59
  60 #include <netinet/kpi_ipfilter.h>
  61
  62 #include <libkern/OSAtomic.h>
  63
  64 #include <kern/debug.h>
  65
  66 #include <sys/mcache.h>
  67
  68 #include <string.h>
  69
  70 struct iptap_softc {
  71         LIST_ENTRY(iptap_softc)         iptap_link;
  72         uint32_t                                        iptap_unit;
  73         uint32_t                                        iptap_dlt_raw_count;
  74         uint32_t                                        iptap_dlt_pkttap_count;
  75         struct ifnet                            *iptap_ifp;
  76 };
  77
  78 static LIST_HEAD(iptap_list, iptap_softc) iptap_list = LIST_HEAD_INITIALIZER(iptap_list);
  79
  80 static void             iptap_lock_shared(void);
  81 static void             iptap_lock_exclusive(void);
  82 static void             iptap_lock_done(void);
  83 static void             iptap_alloc_lock(void);
  84
  85 decl_lck_rw_data(static, iptap_lck_rw);
  86 static lck_grp_t                *iptap_grp;
  87
  88 errno_t iptap_if_output(ifnet_t, mbuf_t);
  89 errno_t iptap_demux(ifnet_t , mbuf_t, char *, protocol_family_t *);
  90 errno_t iptap_add_proto(ifnet_t, protocol_family_t, const struct ifnet_demux_desc *,
  91          u_int32_t);
  92 errno_t iptap_del_proto(ifnet_t, protocol_family_t);
  93 errno_t iptap_getdrvspec(ifnet_t , struct ifdrv64 *);
  94 errno_t iptap_ioctl(ifnet_t, unsigned long, void *);
  95 void iptap_detach(ifnet_t);
  96 errno_t iptap_tap_callback(ifnet_t , u_int32_t , bpf_tap_mode );
  97 int iptap_clone_create(struct if_clone *, u_int32_t, void *);
  98 int iptap_clone_destroy(struct ifnet *);
  99
 100 static int iptap_ipf_register(void);
 101 static int iptap_ipf_unregister(void);
 102 static errno_t iptap_ipf_input(void *, mbuf_t *, int, u_int8_t);
 103 static errno_t iptap_ipf_output(void *, mbuf_t *, ipf_pktopts_t);
 104 static void iptap_ipf_detach(void *);
 105
 106 static ipfilter_t iptap_ipf4, iptap_ipf6;
 107
 108 void iptap_bpf_tap(struct mbuf *m, u_int32_t proto,  int outgoing);
 109
 110 static struct if_clone iptap_cloner =
 111         IF_CLONE_INITIALIZER(IPTAP_IFNAME,
 112                 iptap_clone_create,
 113                 iptap_clone_destroy,
 114                 0,
 115                 IF_MAXUNIT);
 116
 117 SYSCTL_DECL(_net_link);
 118 SYSCTL_NODE(_net_link, OID_AUTO, iptap, CTLFLAG_RW|CTLFLAG_LOCKED, 0,
 119     "iptap virtual interface");
 120
 121 static int iptap_total_tap_count = 0;
 122 SYSCTL_INT(_net_link_iptap, OID_AUTO, total_tap_count,  CTLFLAG_RD | CTLFLAG_LOCKED,
 123         &iptap_total_tap_count, 0, "");
 124
 125 static int iptap_log = 0;
 126 SYSCTL_INT(_net_link_iptap, OID_AUTO, log, CTLFLAG_RW | CTLFLAG_LOCKED,
 127         &iptap_log, 0, "");
 128
 129 #define IPTAP_LOG(fmt, ...) \
 130 do { \
 131     if ((iptap_log)) \
 132         printf("%s:%d " fmt, __FUNCTION__, __LINE__, ##__VA_ARGS__); \
 133 } while(false)
 134
 135 __private_extern__ void
 136 iptap_init(void)
 137 {
 138         errno_t error;
 139
 140         iptap_alloc_lock();
 141
 142         error = if_clone_attach(&iptap_cloner);
 143         if (error != 0)
 144                 panic("%s: if_clone_attach() failed, error %d\n", __func__, error);
 145 }
 146
 147 static void
 148 iptap_alloc_lock(void)
 149 {
 150         lck_grp_attr_t *grp_attr;
 151         lck_attr_t *attr;
 152
 153         grp_attr = lck_grp_attr_alloc_init();
 154         lck_grp_attr_setdefault(grp_attr);
 155         iptap_grp = lck_grp_alloc_init(IPTAP_IFNAME, grp_attr);
 156         lck_grp_attr_free(grp_attr);
 157
 158         attr = lck_attr_alloc_init();
 159         lck_attr_setdefault(attr);
 160
 161         lck_rw_init(&iptap_lck_rw, iptap_grp, attr);
 162         lck_attr_free(attr);
 163 }
 164
 165 static void
 166 iptap_lock_shared(void)
 167 {
 168         lck_rw_lock_shared(&iptap_lck_rw);
 169 }
 170
 171 static void
 172 iptap_lock_exclusive(void)
 173 {
 174         lck_rw_lock_exclusive(&iptap_lck_rw);
 175 }
 176
 177 static void
 178 iptap_lock_done(void)
 179 {
 180         lck_rw_done(&iptap_lck_rw);
 181 }
 182
 183 __private_extern__ int
 184 iptap_clone_create(struct if_clone *ifc, u_int32_t unit, void *params)
 185 {
 186 #pragma unused(params)
 187
 188         int error = 0;
 189         struct iptap_softc *iptap = NULL;
 190         struct ifnet_init_params if_init;
 191
 192         iptap = _MALLOC(sizeof(struct iptap_softc), M_DEVBUF, M_WAITOK | M_ZERO);
 193         if (iptap == NULL) {
 194                 printf("%s: _MALLOC failed\n", __func__);
 195                 error = ENOMEM;
 196                 goto done;
 197         }
 198         iptap->iptap_unit = unit;
 199
 200         /*
 201          * We do not use a set_bpf_tap() function as we rather rely on the more
 202          * accurate callback passed to bpf_attach()
 203          */
 204         bzero(&if_init, sizeof(struct ifnet_init_params));
 205         if_init.name = ifc->ifc_name;
 206         if_init.unit = unit;
 207         if_init.type = IFT_OTHER;
 208         if_init.family = IFNET_FAMILY_LOOPBACK;
 209         if_init.output = iptap_if_output;
 210         if_init.demux = iptap_demux;
 211         if_init.add_proto = iptap_add_proto;
 212         if_init.del_proto = iptap_del_proto;
 213         if_init.softc = iptap;
 214         if_init.ioctl = iptap_ioctl;
 215         if_init.detach = iptap_detach;
 216
 217         error = ifnet_allocate(&if_init, &iptap->iptap_ifp);
 218         if (error != 0) {
 219                 printf("%s: ifnet_allocate failed, error %d\n", __func__, error);
 220                 goto done;
 221         }
 222
 223         ifnet_set_flags(iptap->iptap_ifp, IFF_UP, IFF_UP);
 224
 225         error = ifnet_attach(iptap->iptap_ifp, NULL);
 226         if (error != 0) {
 227                 printf("%s: ifnet_attach failed - error %d\n", __func__, error);
 228                 ifnet_release(iptap->iptap_ifp);
 229                 goto done;
 230         }
 231
 232         /*
 233          * Attach by default as DLT_PKTAP for packet metadata
 234          * Provide DLT_RAW for legacy
 235          */
 236         bpf_attach(iptap->iptap_ifp, DLT_PKTAP, sizeof(struct pktap_header), NULL,
 237                 iptap_tap_callback);
 238         bpf_attach(iptap->iptap_ifp, DLT_RAW, 0, NULL,
 239                 iptap_tap_callback);
 240
 241         /* Take a reference and add to the global list */
 242         ifnet_reference(iptap->iptap_ifp);
 243
 244         iptap_lock_exclusive();
 245
 246         if (LIST_EMPTY(&iptap_list))
 247                 iptap_ipf_register();
 248         LIST_INSERT_HEAD(&iptap_list, iptap, iptap_link);
 249         iptap_lock_done();
 250 done:
 251         if (error != 0) {
 252                 if (iptap != NULL)
 253                         _FREE(iptap, M_DEVBUF);
 254         }
 255         return (error);
 256 }
 257
 258 __private_extern__ int
 259 iptap_clone_destroy(struct ifnet *ifp)
 260 {
 261         int error = 0;
 262
 263         (void) ifnet_detach(ifp);
 264
 265         return (error);
 266 }
 267
 268 /*
 269  * This function is called whenever a DLT is set on the interface:
 270  * - When interface is attached to a BPF device via BIOCSETIF for the default DLT
 271  * - Whenever a new DLT is selected via BIOCSDLT
 272  * - When the interface is detached from a BPF device (direction is zero)
 273  */
 274 __private_extern__ errno_t
 275 iptap_tap_callback(ifnet_t ifp, u_int32_t dlt, bpf_tap_mode direction)
 276 {
 277         struct iptap_softc *iptap;
 278
 279         iptap = ifp->if_softc;
 280         if (iptap == NULL) {
 281                 printf("%s: if_softc is NULL for ifp %s\n", __func__,
 282                     ifp->if_xname);
 283                 goto done;
 284         }
 285         switch (dlt) {
 286                 case DLT_RAW:
 287                         if (direction == 0) {
 288                                 if (iptap->iptap_dlt_raw_count > 0) {
 289                                         iptap->iptap_dlt_raw_count--;
 290                                         OSAddAtomic(-1, &iptap_total_tap_count);
 291
 292                                 }
 293                         } else {
 294                                 iptap->iptap_dlt_raw_count++;
 295                                 OSAddAtomic(1, &iptap_total_tap_count);
 296                         }
 297                         break;
 298                 case DLT_PKTAP:
 299                         if (direction == 0) {
 300                                 if (iptap->iptap_dlt_pkttap_count > 0) {
 301                                         iptap->iptap_dlt_pkttap_count--;
 302                                         OSAddAtomic(-1, &iptap_total_tap_count);
 303                                 }
 304                         } else {
 305                                 iptap->iptap_dlt_pkttap_count++;
 306                                 OSAddAtomic(1, &iptap_total_tap_count);
 307                         }
 308                         break;
 309         }
 310 done:
 311         /*
 312          * Attachements count must be positive and we're in trouble
 313          * if we have more that 2**31 attachements
 314          */
 315         VERIFY(iptap_total_tap_count >= 0);
 316
 317         return (0);
 318 }
 319
 320 __private_extern__ errno_t
 321 iptap_if_output(ifnet_t ifp, mbuf_t m)
 322 {
 323 #pragma unused(ifp)
 324
 325         mbuf_freem(m);
 326         return (ENOTSUP);
 327 }
 328
 329 __private_extern__ errno_t
 330 iptap_demux(ifnet_t ifp, mbuf_t m, char *header,
 331         protocol_family_t *ppf)
 332 {
 333 #pragma unused(ifp)
 334 #pragma unused(m)
 335 #pragma unused(header)
 336 #pragma unused(ppf)
 337
 338         return (ENOTSUP);
 339 }
 340
 341 __private_extern__ errno_t
 342 iptap_add_proto(ifnet_t ifp, protocol_family_t pf,
 343     const struct ifnet_demux_desc *dmx, u_int32_t cnt)
 344 {
 345 #pragma unused(ifp)
 346 #pragma unused(pf)
 347 #pragma unused(dmx)
 348 #pragma unused(cnt)
 349
 350         return (0);
 351 }
 352
 353 __private_extern__ errno_t
 354 iptap_del_proto(ifnet_t ifp, protocol_family_t pf)
 355 {
 356 #pragma unused(ifp)
 357 #pragma unused(pf)
 358
 359         return (0);
 360 }
 361
 362 __private_extern__ errno_t
 363 iptap_getdrvspec(ifnet_t ifp, struct ifdrv64 *ifd)
 364 {
 365         errno_t error = 0;
 366         struct iptap_softc *iptap;
 367
 368         iptap = ifp->if_softc;
 369         if (iptap == NULL) {
 370                 error = ENOENT;
 371                 printf("%s: iptap NULL - error %d\n", __func__, error);
 372                 goto done;
 373         }
 374
 375         switch (ifd->ifd_cmd) {
 376         case PKTP_CMD_TAP_COUNT: {
 377                 uint32_t tap_count = iptap->iptap_dlt_raw_count + iptap->iptap_dlt_pkttap_count;
 378
 379                 if (ifd->ifd_len < sizeof(tap_count)) {
 380                         printf("%s: PKTP_CMD_TAP_COUNT ifd_len %llu too small - error %d\n",
 381                                 __func__, ifd->ifd_len, error);
 382                         error = EINVAL;
 383                         break;
 384                 }
 385                 error = copyout(&tap_count, ifd->ifd_data, sizeof(tap_count));
 386                 if (error) {
 387                         printf("%s: PKTP_CMD_TAP_COUNT copyout - error %d\n", __func__, error);
 388                         goto done;
 389                 }
 390                 break;
 391         }
 392         default:
 393                 error = EINVAL;
 394                 break;
 395         }
 396
 397 done:
 398         return (error);
 399 }
 400
 401 __private_extern__ errno_t
 402 iptap_ioctl(ifnet_t ifp, unsigned long cmd, void *data)
 403 {
 404         errno_t error = 0;
 405
 406         if ((cmd & IOC_IN)) {
 407                 error = kauth_authorize_generic(kauth_cred_get(), KAUTH_GENERIC_ISSUSER);
 408                 if (error) {
 409                         goto done;
 410                 }
 411         }
 412
 413         switch (cmd) {
 414         case SIOCGDRVSPEC32: {
 415                 struct ifdrv64 ifd;
 416                 struct ifdrv32 *ifd32 = (struct ifdrv32 *)data;
 417
 418                 memcpy(ifd.ifd_name, ifd32->ifd_name, sizeof(ifd.ifd_name));
 419                 ifd.ifd_cmd = ifd32->ifd_cmd;
 420                 ifd.ifd_len = ifd32->ifd_len;
 421                 ifd.ifd_data = ifd32->ifd_data;
 422
 423                 error = iptap_getdrvspec(ifp, &ifd);
 424
 425                 break;
 426         }
 427         case SIOCGDRVSPEC64: {
 428                 struct ifdrv64 *ifd64 = (struct ifdrv64 *)data;
 429
 430                 error = iptap_getdrvspec(ifp, ifd64);
 431
 432                 break;
 433         }
 434         default:
 435                 error = ENOTSUP;
 436                 break;
 437         }
 438 done:
 439         return (error);
 440 }
 441
 442 __private_extern__ void
 443 iptap_detach(ifnet_t ifp)
 444 {
 445         struct iptap_softc *iptap;
 446
 447         iptap_lock_exclusive();
 448
 449         iptap = ifp->if_softc;
 450         ifp->if_softc = NULL;
 451         LIST_REMOVE(iptap, iptap_link);
 452
 453         if (LIST_EMPTY(&iptap_list))
 454                 iptap_ipf_unregister();
 455
 456         iptap_lock_done();
 457
 458         /* Drop reference as it's no more on the global list */
 459         ifnet_release(ifp);
 460
 461         _FREE(iptap, M_DEVBUF);
 462
 463         /* This is for the reference taken by ifnet_attach() */
 464         (void) ifnet_release(ifp);
 465 }
 466
 467 static int
 468 iptap_ipf_register(void)
 469 {
 470         struct ipf_filter iptap_ipfinit;
 471         int err = 0;
 472
 473         IPTAP_LOG("\n");
 474
 475         bzero(&iptap_ipfinit, sizeof (iptap_ipfinit));
 476         iptap_ipfinit.name = IPTAP_IFNAME;
 477         iptap_ipfinit.cookie = &iptap_ipf4;
 478         iptap_ipfinit.ipf_input = iptap_ipf_input;
 479         iptap_ipfinit.ipf_output = iptap_ipf_output;
 480         iptap_ipfinit.ipf_detach = iptap_ipf_detach;
 481
 482         err = ipf_addv4(&iptap_ipfinit, &iptap_ipf4);
 483         if (err != 0) {
 484                 printf("%s: ipf_addv4 for %s0 failed - %d\n",
 485                     __func__, IPTAP_IFNAME, err);
 486                 goto done;
 487         }
 488
 489         iptap_ipfinit.cookie = &iptap_ipf6;
 490         err = ipf_addv6(&iptap_ipfinit, &iptap_ipf6);
 491         if (err != 0) {
 492                 printf("%s: ipf_addv6 for %s0 failed - %d\n",
 493                     __func__, IPTAP_IFNAME, err);
 494                 (void) ipf_remove(iptap_ipf4);
 495                 iptap_ipf4 = NULL;
 496                 goto done;
 497         }
 498
 499 done:
 500         return (err);
 501 }
 502
 503 static int
 504 iptap_ipf_unregister(void)
 505 {
 506         int err = 0;
 507
 508         IPTAP_LOG("\n");
 509
 510         if (iptap_ipf4 != NULL) {
 511                 err = ipf_remove(iptap_ipf4);
 512                 if (err != 0) {
 513                         printf("%s: ipf_remove (ipv4) for %s0 failed - %d\n",
 514                             __func__, IPTAP_IFNAME, err);
 515                         goto done;
 516                 }
 517                 iptap_ipf4 = NULL;
 518         }
 519
 520         if (iptap_ipf6 != NULL) {
 521                 err = ipf_remove(iptap_ipf6);
 522                 if (err != 0) {
 523                         printf("%s: ipf_remove (ipv6) for %s0 failed - %d\n",
 524                             __func__, IPTAP_IFNAME, err);
 525                         goto done;
 526                 }
 527                 iptap_ipf6 = NULL;
 528         }
 529 done:
 530         return (err);
 531 }
 532
 533 static errno_t
 534 iptap_ipf_input(void *arg, mbuf_t *mp,  int off, u_int8_t proto)
 535 {
 536 #pragma unused(off)
 537 #pragma unused(proto)
 538
 539         if (arg == (void *)&iptap_ipf4)
 540                 iptap_bpf_tap(*mp, AF_INET, 0);
 541         else if (arg == (void *)&iptap_ipf6)
 542                 iptap_bpf_tap(*mp, AF_INET6, 0);
 543         else
 544                 IPTAP_LOG("%s:%d bad cookie 0x%llx &iptap_ipf4 0x%llx "
 545                     "&iptap_ipf6 0x%llx\n", __func__, __LINE__,
 546                     (uint64_t)VM_KERNEL_ADDRPERM(arg),
 547                     (uint64_t)VM_KERNEL_ADDRPERM(&iptap_ipf4),
 548                     (uint64_t)VM_KERNEL_ADDRPERM(&iptap_ipf6));
 549
 550         return (0);
 551 }
 552
 553 static errno_t
 554 iptap_ipf_output(void *arg, mbuf_t *mp, ipf_pktopts_t opt)
 555 {
 556 #pragma unused(opt)
 557
 558         if (arg == (void *)&iptap_ipf4)
 559                 iptap_bpf_tap(*mp, AF_INET, 1);
 560         else if (arg == (void *)&iptap_ipf6)
 561                 iptap_bpf_tap(*mp, AF_INET6, 1);
 562         else
 563                 IPTAP_LOG("%s:%d bad cookie 0x%llx &iptap_ipf4 0x%llx "
 564                     "&iptap_ipf6 0x%llx\n", __func__, __LINE__,
 565                     (uint64_t)VM_KERNEL_ADDRPERM(arg),
 566                     (uint64_t)VM_KERNEL_ADDRPERM(&iptap_ipf4),
 567                     (uint64_t)VM_KERNEL_ADDRPERM(&iptap_ipf6));
 568
 569         return (0);
 570 }
 571
 572 static void
 573 iptap_ipf_detach(void *arg)
 574 {
 575 #pragma unused(arg)
 576 }
 577
 578 __private_extern__ void
 579 iptap_bpf_tap(struct mbuf *m, u_int32_t proto,  int outgoing)
 580 {
 581         struct iptap_softc *iptap;
 582         void (*bpf_tap_func)(ifnet_t , u_int32_t , mbuf_t , void * , size_t ) =
 583                 outgoing ? bpf_tap_out : bpf_tap_in;
 584
 585         iptap_lock_shared();
 586
 587         LIST_FOREACH(iptap, &iptap_list, iptap_link) {
 588                         if (iptap->iptap_dlt_raw_count > 0) {
 589                                         bpf_tap_func(iptap->iptap_ifp, DLT_RAW, m,
 590                                                 NULL, 0);
 591                         }
 592                         if (iptap->iptap_dlt_pkttap_count > 0) {
 593                                 struct {
 594                                         struct pktap_header hdr;
 595                                         u_int32_t proto;
 596                                 } hdr_buffer;
 597                                 struct pktap_header *hdr = &hdr_buffer.hdr;
 598                                 size_t hdr_size = sizeof(hdr_buffer);
 599                                 struct ifnet *ifp = outgoing ? NULL : m->m_pkthdr.rcvif;
 600
 601                                 /* Verify the structure is packed */
 602                                 _CASSERT(sizeof(hdr_buffer) == sizeof(struct pktap_header) + sizeof(u_int32_t));
 603
 604                                 bzero(hdr, sizeof(hdr_buffer));
 605                                 hdr->pth_length = sizeof(struct pktap_header);
 606                                 hdr->pth_type_next = PTH_TYPE_PACKET;
 607                                 hdr->pth_dlt = DLT_NULL;
 608                                 if (ifp != NULL)
 609                                         snprintf(hdr->pth_ifname, sizeof(hdr->pth_ifname), "%s",
 610                                                 ifp->if_xname);
 611                                 hdr_buffer.proto = proto;
 612                                 hdr->pth_flags = outgoing ? PTH_FLAG_DIR_OUT : PTH_FLAG_DIR_IN;
 613                                 hdr->pth_protocol_family = proto;
 614                                 hdr->pth_frame_pre_length = 0;
 615                                 hdr->pth_frame_post_length = 0;
 616                                 hdr->pth_iftype = ifp != NULL ? ifp->if_type : 0;
 617                                 hdr->pth_ifunit = ifp != NULL ? ifp->if_unit : 0;
 618
 619                                 pktap_fill_proc_info(hdr, proto, m, 0, outgoing, ifp);
 620
 621                                 hdr->pth_svc = so_svc2tc(m->m_pkthdr.pkt_svc);
 622
 623                                 bpf_tap_func(iptap->iptap_ifp, DLT_PKTAP, m, hdr, hdr_size);
 624                         }
 625         }
 626
 627         iptap_lock_done();
 628 }