extcap.c

   1 /* extcap.h
   2  *
   3  * Routines for extcap external capture
   4  * Copyright 2013, Mike Ryan <mikeryan@lacklustre.net>
   5  *
   6  * Wireshark - Network traffic analyzer
   7  * By Gerald Combs <gerald@wireshark.org>
   8  * Copyright 1998 Gerald Combs
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License
  12  * as published by the Free Software Foundation; either version 2
  13  * of the License, or (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  23  */
  24
  25 #include <config.h>
  26
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30
  31 #ifdef _WIN32
  32 #include <windows.h>
  33 #include <process.h>
  34 #include <time.h>
  35 #else
  36 /* Include for unlink */
  37 #include <unistd.h>
  38 #endif
  39
  40 #include <glib.h>
  41 #include <log.h>
  42
  43 #include <epan/prefs.h>
  44 #include <epan/prefs-int.h>
  45
  46 #include <wsutil/file_util.h>
  47 #include <wsutil/filesystem.h>
  48 #include <wsutil/tempfile.h>
  49
  50 #include "capture_opts.h"
  51
  52 #ifdef HAVE_EXTCAP
  53
  54 #include "extcap.h"
  55 #include "extcap_parser.h"
  56
  57 #ifdef _WIN32
  58 static HANDLE pipe_h = NULL;
  59 #endif
  60
  61 /* internal container, for all the extcap interfaces that have been found.
  62  * will be resetted by every call to extcap_interface_list() and is being
  63  * used in extcap_get_if_* as well as extcap_init_interfaces to ensure,
  64  * that only extcap interfaces are being given to underlying extcap programs
  65  */
  66 static GHashTable *ifaces = NULL;
  67
  68 /* internal container, for all the extcap executables that have been found.
  69  * will be resetted by every call to extcap_interface_list() and is being
  70  * used for printing information about all extcap interfaces found
  71  */
  72 static GHashTable *tools = NULL;
  73
  74 /* Callback definition for extcap_foreach */
  75 typedef gboolean (*extcap_cb_t)(const gchar *extcap, const gchar *ifname, gchar *output, void *data,
  76         gchar **err_str);
  77
  78 /* #define ARG_DEBUG */
  79 #if ARG_DEBUG
  80 static void extcap_debug_arguments ( extcap_arg *arg_iter );
  81 #endif
  82
  83 static gboolean
  84 extcap_if_exists(const gchar *ifname)
  85 {
  86     if ( !ifname || !ifaces )
  87         return FALSE;
  88
  89     if ( g_hash_table_lookup(ifaces, ifname) )
  90         return TRUE;
  91
  92     return FALSE;
  93 }
  94
  95 static gboolean
  96 extcap_if_exists_for_extcap(const gchar *ifname, const gchar *extcap)
  97 {
  98     gchar *entry = (gchar *)g_hash_table_lookup(ifaces, ifname);
  99
 100     if ( entry && strcmp(entry, extcap) == 0 )
 101         return TRUE;
 102
 103     return FALSE;
 104 }
 105
 106 static gchar *
 107 extcap_if_executable(const gchar *ifname)
 108 {
 109     return (gchar *)g_hash_table_lookup(ifaces, ifname);
 110 }
 111
 112 static void
 113 extcap_if_add(const gchar *ifname, const gchar *extcap)
 114 {
 115     if ( !g_hash_table_lookup(ifaces, ifname) )
 116         g_hash_table_insert(ifaces, g_strdup(ifname), g_strdup(extcap));
 117 }
 118
 119 static void
 120 extcap_tool_add(const gchar *extcap, const extcap_interface *interface)
 121 {
 122     char *toolname;
 123
 124     if ( !extcap || !interface )
 125         return;
 126
 127     toolname = g_path_get_basename(extcap);
 128
 129     if ( !g_hash_table_lookup(tools, toolname) ) {
 130         extcap_info * store = (extcap_info *)g_new0(extcap_info, 1);
 131         store->version = g_strdup(interface->version);
 132         store->full_path = g_strdup(extcap);
 133         store->basename = g_strdup(toolname);
 134
 135         g_hash_table_insert(tools, g_strdup(toolname), store);
 136     }
 137
 138     g_free(toolname);
 139 }
 140
 141 /* Note: args does not need to be NULL-terminated. */
 142 static void extcap_foreach(gint argc, gchar **args, extcap_cb_t cb,
 143         void *cb_data, char **err_str, const char * ifname _U_) {
 144     const char *dirname = get_extcap_dir();
 145     GDir *dir;
 146     const gchar *file;
 147     gboolean keep_going;
 148     gint i;
 149     gchar **argv;
 150 #ifdef _WIN32
 151     gchar **dll_search_envp;
 152     gchar *progfile_dir;
 153 #endif
 154
 155     keep_going = TRUE;
 156
 157     argv = (gchar **) g_malloc0(sizeof(gchar *) * (argc + 2));
 158
 159 #ifdef _WIN32
 160     /*
 161      * Make sure executables can find dependent DLLs and that they're *our*
 162      * DLLs: https://msdn.microsoft.com/en-us/library/windows/desktop/ms682586.aspx
 163      * Alternatively we could create a simple wrapper exe similar to Create
 164      * Hidden Process (http://www.commandline.co.uk/chp/).
 165      */
 166     dll_search_envp = g_get_environ();
 167     progfile_dir = g_strdup_printf("%s;%s", get_progfile_dir(), g_environ_getenv(dll_search_envp, "Path"));
 168     dll_search_envp = g_environ_setenv(dll_search_envp, "Path", progfile_dir, TRUE);
 169     g_free(progfile_dir);
 170 #endif
 171
 172     if ((dir = g_dir_open(dirname, 0, NULL)) != NULL) {
 173         GString *extcap_path = NULL;
 174
 175         extcap_path = g_string_new("");
 176         while (keep_going && (file = g_dir_read_name(dir)) != NULL ) {
 177             gchar *command_output = NULL;
 178             gboolean status = FALSE;
 179             gint exit_status = 0;
 180             gchar **envp = NULL;
 181
 182             /* full path to extcap binary */
 183 #ifdef _WIN32
 184             g_string_printf(extcap_path, "%s\\%s", dirname, file);
 185             envp = dll_search_envp;
 186 #else
 187             g_string_printf(extcap_path, "%s/%s", dirname, file);
 188 #endif
 189             if ( extcap_if_exists(ifname) && !extcap_if_exists_for_extcap(ifname, extcap_path->str ) )
 190                 continue;
 191
 192 #ifdef _WIN32
 193             argv[0] = g_strescape(extcap_path->str, NULL);
 194 #else
 195             argv[0] = g_strdup(extcap_path->str);
 196 #endif
 197             for (i = 0; i < argc; ++i)
 198                 argv[i+1] = args[i];
 199             argv[argc+1] = NULL;
 200
 201             status = g_spawn_sync(dirname, argv, envp,
 202                 (GSpawnFlags) 0, NULL, NULL,
 203                     &command_output, NULL, &exit_status, NULL);
 204
 205             if (status && exit_status == 0)
 206             keep_going = cb(extcap_path->str, ifname, command_output, cb_data, err_str);
 207
 208             g_free(argv[0]);
 209             g_free(command_output);
 210         }
 211
 212         g_dir_close(dir);
 213         g_string_free(extcap_path, TRUE);
 214     }
 215
 216 #ifdef _WIN32
 217     g_strfreev(dll_search_envp);
 218 #endif
 219     g_free(argv);
 220 }
 221
 222 static gboolean dlt_cb(const gchar *extcap _U_, const gchar *ifname _U_, gchar *output, void *data,
 223         char **err_str) {
 224     extcap_token_sentence *tokens;
 225     extcap_dlt *dlts, *dlt_iter, *next;
 226     if_capabilities_t *caps;
 227     GList *linktype_list = NULL;
 228     data_link_info_t *data_link_info;
 229
 230     tokens = extcap_tokenize_sentences(output);
 231     extcap_parse_dlts(tokens, &dlts);
 232
 233     extcap_free_tokenized_sentence_list(tokens);
 234
 235     g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "Extcap pipe %s ", extcap);
 236
 237     /*
 238      * Allocate the interface capabilities structure.
 239      */
 240     caps = (if_capabilities_t *) g_malloc(sizeof *caps);
 241     caps->can_set_rfmon = FALSE;
 242
 243     dlt_iter = dlts;
 244     while (dlt_iter != NULL ) {
 245         g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
 246                 "  DLT %d name=\"%s\" display=\"%s\" ", dlt_iter->number,
 247                 dlt_iter->name, dlt_iter->display);
 248
 249         data_link_info = g_new(data_link_info_t, 1);
 250         data_link_info->dlt = dlt_iter->number;
 251         data_link_info->name = g_strdup(dlt_iter->name);
 252         data_link_info->description = g_strdup(dlt_iter->display);
 253         linktype_list = g_list_append(linktype_list, data_link_info);
 254         dlt_iter = dlt_iter->next_dlt;
 255     }
 256
 257     /* Check to see if we built a list */
 258     if (linktype_list != NULL && data != NULL) {
 259         caps->data_link_types = linktype_list;
 260         *(if_capabilities_t **) data = caps;
 261     } else {
 262         if (err_str) {
 263             g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "  returned no DLTs");
 264             *err_str = g_strdup("Extcap returned no DLTs");
 265         }
 266         g_free(caps);
 267     }
 268
 269     dlt_iter = dlts;
 270     while (dlt_iter != NULL ) {
 271         next = dlt_iter->next_dlt;
 272         extcap_free_dlt(dlt_iter);
 273         dlt_iter = next;
 274     }
 275
 276     return FALSE;
 277 }
 278
 279 if_capabilities_t *
 280 extcap_get_if_dlts(const gchar *ifname, char **err_str) {
 281     gchar *argv[3];
 282     gint i;
 283     if_capabilities_t *caps = NULL;
 284
 285     if (err_str != NULL)
 286         *err_str = NULL;
 287
 288     if ( extcap_if_exists(ifname) )
 289     {
 290         argv[0] = g_strdup(EXTCAP_ARGUMENT_LIST_DLTS);
 291         argv[1] = g_strdup(EXTCAP_ARGUMENT_INTERFACE);
 292         argv[2] = g_strdup(ifname);
 293
 294         extcap_foreach(3, argv, dlt_cb, &caps, err_str, ifname);
 295
 296         for (i = 0; i < 3; ++i)
 297             g_free(argv[i]);
 298     }
 299
 300     return caps;
 301 }
 302
 303 static gboolean interfaces_cb(const gchar *extcap, const gchar *ifname _U_, gchar *output, void *data,
 304         char **err_str _U_) {
 305     GList **il = (GList **) data;
 306     extcap_token_sentence *tokens;
 307     extcap_interface *interfaces, *int_iter; /*, *next; */
 308     if_info_t *if_info;
 309
 310     tokens = extcap_tokenize_sentences(output);
 311     extcap_parse_interfaces(tokens, &interfaces);
 312
 313     extcap_free_tokenized_sentence_list(tokens);
 314
 315     g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "Extcap pipe %s ", extcap);
 316
 317     int_iter = interfaces;
 318     while (int_iter != NULL ) {
 319         if ( int_iter->if_type == EXTCAP_SENTENCE_INTERFACE && extcap_if_exists(int_iter->call) )
 320         {
 321             g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_WARNING, "Extcap interface \"%s\" is already provided by \"%s\" ",
 322                     int_iter->call, (gchar *)extcap_if_executable(int_iter->call) );
 323             int_iter = int_iter->next_interface;
 324             continue;
 325         }
 326
 327         if ( int_iter->if_type == EXTCAP_SENTENCE_INTERFACE )
 328             g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "  Interface [%s] \"%s\" ",
 329                     int_iter->call, int_iter->display);
 330         else if ( int_iter->if_type == EXTCAP_SENTENCE_EXTCAP )
 331             g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "  Extcap [%s] ", int_iter->call);
 332
 333         if ( int_iter->if_type == EXTCAP_SENTENCE_INTERFACE ) {
 334             if_info = g_new0(if_info_t, 1);
 335             if_info->name = g_strdup(int_iter->call);
 336             if_info->friendly_name = g_strdup(int_iter->display);
 337
 338             if_info->type = IF_EXTCAP;
 339
 340             if_info->extcap = g_strdup(extcap);
 341             *il = g_list_append(*il, if_info);
 342
 343             extcap_if_add(int_iter->call, extcap);
 344         }
 345
 346         /* Call for interfaces and tools alike. Multiple calls (because a tool has multiple
 347          * interfaces) are handled internally */
 348         extcap_tool_add(extcap, int_iter);
 349
 350         int_iter = int_iter->next_interface;
 351     }
 352     extcap_free_interface(interfaces);
 353
 354     return TRUE;
 355 }
 356
 357 static gint
 358 if_info_compare(gconstpointer a, gconstpointer b)
 359 {
 360     gint comp = 0;
 361     if_info_t * if_a = (if_info_t *)a;
 362     if_info_t * if_b = (if_info_t *)b;
 363
 364     if ( (comp = g_strcmp0(if_a->name, if_b->name)) == 0 )
 365         return g_strcmp0(if_a->friendly_name, if_b->friendly_name);
 366
 367     return comp;
 368 }
 369
 370 GHashTable *
 371 extcap_tools_list(void) {
 372     if ( tools == NULL || g_hash_table_size(tools) == 0 )
 373         extcap_interface_list(NULL);
 374
 375     return tools;
 376 }
 377
 378 static void
 379 extcap_free_info (gpointer data) {
 380     extcap_info * info = (extcap_info *)data;
 381
 382     g_free (info->basename);
 383     g_free (info->full_path);
 384     g_free (info->version);
 385     g_free (info);
 386 }
 387
 388 GList *
 389 extcap_interface_list(char **err_str) {
 390     gchar *argv;
 391     /* gint i; */
 392     GList *ret = NULL;
 393
 394     if (err_str != NULL)
 395         *err_str = NULL;
 396
 397     /* ifaces is used as cache, do not destroy its contents when
 398      * returning or no extcap interfaces can be queried for options */
 399     if (ifaces == NULL)
 400         ifaces = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, g_free);
 401     else
 402         g_hash_table_remove_all(ifaces);
 403
 404     if (tools == NULL)
 405         tools = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, extcap_free_info);
 406     else
 407         g_hash_table_remove_all(tools);
 408
 409     argv = g_strdup(EXTCAP_ARGUMENT_LIST_INTERFACES);
 410
 411     extcap_foreach(1, &argv, interfaces_cb, &ret, err_str, NULL);
 412
 413     g_free(argv);
 414
 415     return g_list_sort ( ret, if_info_compare );
 416 }
 417
 418 static void extcap_free_arg_elem(gpointer data, gpointer user_data _U_) {
 419     extcap_free_arg((extcap_arg *) data);
 420     g_free(data);
 421 }
 422
 423 void extcap_register_preferences(void)
 424 {
 425     GList * interfaces = NULL;
 426
 427     module_t * dev_module = prefs_find_module("extcap");
 428
 429     if ( !dev_module )
 430         return;
 431
 432     if ( ! ifaces || g_hash_table_size(ifaces) == 0 )
 433         extcap_interface_list(NULL);
 434
 435     interfaces = g_hash_table_get_keys(ifaces);
 436
 437     while ( interfaces ) {
 438         extcap_get_if_configuration((gchar *)interfaces->data);
 439
 440         interfaces = g_list_next(interfaces);
 441     }
 442 }
 443
 444 static void extcap_free_if_configuration(GList *list)
 445 {
 446     GList *elem, *sl;
 447
 448     for (elem = g_list_first(list); elem; elem = elem->next)
 449     {
 450         if (elem->data != NULL) {
 451             /* g_list_free_full() only exists since 2.28. */
 452             sl = g_list_first((GList *)elem->data);
 453             g_list_foreach(sl, (GFunc)extcap_free_arg_elem, NULL);
 454             g_list_free(sl);
 455         }
 456     }
 457     g_list_free(list);
 458 }
 459
 460 gchar * extcap_settings_key(const gchar * ifname, const gchar * setting)
 461 {
 462     gchar * setting_nohyphen;
 463     gchar * ifname_underscore;
 464     gchar * ifname_lower;
 465     gchar * key;
 466     GRegex * regex = g_regex_new ("(?![a-zA-Z1-9_]).", (GRegexCompileFlags) 0, (GRegexMatchFlags) 0, NULL );
 467
 468     if (!regex)
 469         return NULL;
 470
 471     setting_nohyphen =
 472         g_regex_replace_literal(regex, setting, strlen(setting), 0,
 473             "", (GRegexMatchFlags) 0, NULL );
 474     ifname_underscore =
 475         g_regex_replace_literal(regex, ifname, strlen(ifname), 0,
 476             "_", (GRegexMatchFlags) 0, NULL );
 477     ifname_lower = g_utf8_strdown(ifname_underscore, -1);
 478     key = g_strconcat(ifname_lower, ".", setting_nohyphen, NULL);
 479
 480     g_free(setting_nohyphen);
 481     g_free(ifname_underscore);
 482     g_free(ifname_lower);
 483     g_regex_unref(regex);
 484
 485     return key;
 486 }
 487
 488 static gboolean search_cb(const gchar *extcap _U_, const gchar *ifname _U_, gchar *output, void *data,
 489         char **err_str _U_) {
 490     extcap_token_sentence *tokens = NULL;
 491     GList *arguments = NULL;
 492     GList **il = (GList **) data;
 493     module_t * dev_module = NULL;
 494
 495     tokens = extcap_tokenize_sentences(output);
 496     arguments = extcap_parse_args(tokens);
 497
 498     extcap_free_tokenized_sentence_list(tokens);
 499
 500 #if ARG_DEBUG
 501     extcap_debug_arguments ( arguments );
 502 #endif
 503
 504     dev_module = prefs_find_module("extcap");
 505
 506     if ( dev_module ) {
 507         GList * walker = arguments;
 508
 509         while ( walker != NULL ) {
 510             extcap_arg * arg = (extcap_arg *)walker->data;
 511
 512             if ( arg->save ) {
 513                 struct preference * pref = NULL;
 514                 gchar * pref_ifname = extcap_settings_key(ifname, arg->call);
 515
 516                 if ( ( pref = prefs_find_preference(dev_module, pref_ifname) ) == NULL ) {
 517                     /* Set an initial value */
 518                     if ( ! arg->storeval && arg->default_complex )
 519                         arg->storeval = g_strdup(arg->default_complex->_val);
 520
 521                     prefs_register_string_preference(dev_module, g_strdup(pref_ifname),
 522                             arg->display, arg->display, (const gchar **)&(arg->storeval));
 523                 } else {
 524                     /* Been here before, restore stored value */
 525                     if (! arg->storeval && pref->varp.string)
 526                         arg->storeval = g_strdup(*(pref->varp.string));
 527                     }
 528                 g_free(pref_ifname);
 529             }
 530
 531             walker = g_list_next(walker);
 532         }
 533     }
 534
 535     *il = g_list_append(*il, arguments);
 536
 537     /* By returning false, extcap_foreach will break on first found */
 538     return TRUE;
 539 }
 540
 541 GList *
 542 extcap_get_if_configuration(const char * ifname) {
 543     gchar *argv[3];
 544     GList *ret = NULL;
 545     gchar **err_str = NULL;
 546     int i;
 547
 548     if ( extcap_if_exists(ifname) )
 549     {
 550         g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "Extcap path %s",
 551                 get_extcap_dir());
 552
 553         argv[0] = g_strdup(EXTCAP_ARGUMENT_CONFIG);
 554         argv[1] = g_strdup(EXTCAP_ARGUMENT_INTERFACE);
 555         argv[2] = g_strdup(ifname);
 556
 557         extcap_foreach(3, argv, search_cb, &ret, err_str, ifname);
 558
 559         for (i = 0; i < 3; i++)
 560             g_free(argv[i]);
 561     }
 562
 563     return ret;
 564 }
 565
 566 gboolean
 567 extcap_has_configuration(const char * ifname, gboolean is_required) {
 568     GList * arguments = 0;
 569     GList * walker = 0, * item = 0;
 570
 571     gboolean found = FALSE;
 572
 573     arguments = extcap_get_if_configuration((const char *)( ifname ) );
 574     walker = g_list_first(arguments);
 575
 576     while ( walker != NULL && ! found ) {
 577         item = g_list_first((GList *)(walker->data));
 578         while ( item != NULL && ! found ) {
 579             if ( (extcap_arg *)(item->data) != NULL ) {
 580                 extcap_arg * arg = (extcap_arg *)(item->data);
 581                 /* Should required options be present, or any kind of options */
 582                 if ( ! is_required )
 583                     found = TRUE;
 584                 else if ( arg->is_required ) {
 585                     gchar * stored = NULL;
 586                     gchar * defval = NULL;
 587
 588                     if ( arg->storeval != NULL )
 589                         stored = arg->storeval;
 590
 591                     if ( arg->default_complex != NULL && arg->default_complex->_val != NULL )
 592                         defval = arg->default_complex->_val;
 593
 594                     if ( arg->is_required ) {
 595                         /* If stored and defval is identical and the argument is required,
 596                          * configuration is needed */
 597                         if ( defval && stored && g_strcmp0(stored, defval) == 0 )
 598                             found = TRUE;
 599                         else if ( ! defval && (!stored || strlen(g_strchomp(stored)) <= (size_t)0) )
 600                             found = TRUE;
 601                     }
 602
 603                     if ( arg->arg_type == EXTCAP_ARG_FILESELECT ) {
 604                         if ( arg->fileexists && ! ( file_exists(defval) || file_exists(stored) ) )
 605                             found = TRUE;
 606                     }
 607                 }
 608             }
 609
 610             item = item->next;
 611         }
 612         walker = walker->next;
 613     }
 614     extcap_free_if_configuration(arguments);
 615
 616     return found;
 617 }
 618
 619 void extcap_cleanup(capture_options * capture_opts) {
 620     interface_options interface_opts;
 621     guint icnt = 0;
 622
 623     for (icnt = 0; icnt < capture_opts->ifaces->len; icnt++) {
 624         interface_opts = g_array_index(capture_opts->ifaces, interface_options,
 625                 icnt);
 626
 627         /* skip native interfaces */
 628         if (interface_opts.if_type != IF_EXTCAP)
 629         continue;
 630
 631         g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
 632                 "Extcap [%s] - Cleaning up fifo: %s; PID: %d", interface_opts.name,
 633                 interface_opts.extcap_fifo, interface_opts.extcap_pid);
 634 #ifdef _WIN32
 635         if (pipe_h)
 636         {
 637             g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
 638                 "Extcap [%s] - Closing pipe", interface_opts.name);
 639             FlushFileBuffers(pipe_h);
 640             DisconnectNamedPipe(pipe_h);
 641             CloseHandle(pipe_h);
 642         }
 643 #else
 644         if (interface_opts.extcap_fifo != NULL && file_exists(interface_opts.extcap_fifo))
 645         {
 646             /* the fifo will not be freed here, but with the other capture_opts in capture_sync */
 647             ws_unlink(interface_opts.extcap_fifo);
 648             interface_opts.extcap_fifo = NULL;
 649         }
 650 #endif
 651         /* Maybe the client closed and removed fifo, but ws should check if
 652          * pid should be closed */
 653         g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
 654                 "Extcap [%s] - Closing spawned PID: %d", interface_opts.name,
 655                 interface_opts.extcap_pid);
 656
 657         if (interface_opts.extcap_pid != INVALID_EXTCAP_PID)
 658         {
 659 #ifdef _WIN32
 660             TerminateProcess(interface_opts.extcap_pid, 0);
 661 #endif
 662             g_spawn_close_pid(interface_opts.extcap_pid);
 663             interface_opts.extcap_pid = INVALID_EXTCAP_PID;
 664         }
 665
 666         /* Make sure modified interface_opts is saved in capture_opts. */
 667         capture_opts->ifaces = g_array_remove_index(capture_opts->ifaces, icnt);
 668         g_array_insert_val(capture_opts->ifaces, icnt, interface_opts);
 669     }
 670 }
 671
 672 static gboolean
 673 extcap_add_arg_and_remove_cb(gpointer key, gpointer value, gpointer data) {
 674     GPtrArray *args = (GPtrArray *)data;
 675
 676     if ( key != NULL )
 677     {
 678         g_ptr_array_add(args, g_strdup((const gchar*)key));
 679
 680         if ( value != NULL )
 681             g_ptr_array_add(args, g_strdup((const gchar*)value));
 682
 683         return TRUE;
 684     }
 685
 686     return FALSE;
 687 }
 688
 689 static void extcap_child_watch_cb(GPid pid, gint status _U_, gpointer user_data)
 690 {
 691     guint i;
 692     interface_options interface_opts;
 693     capture_options *capture_opts = (capture_options *)user_data;
 694
 695     /* Close handle to child process. */
 696     g_spawn_close_pid(pid);
 697
 698     /* Update extcap_pid in interface options structure. */
 699     for (i = 0; i < capture_opts->ifaces->len; i++)
 700     {
 701         interface_opts = g_array_index(capture_opts->ifaces, interface_options, i);
 702         if (interface_opts.extcap_pid == pid)
 703         {
 704             interface_opts.extcap_pid = INVALID_EXTCAP_PID;
 705             g_source_remove(interface_opts.extcap_child_watch);
 706             interface_opts.extcap_child_watch = 0;
 707
 708             capture_opts->ifaces = g_array_remove_index(capture_opts->ifaces, i);
 709             g_array_insert_val(capture_opts->ifaces, i, interface_opts);
 710             break;
 711         }
 712     }
 713 }
 714
 715 /* call mkfifo for each extcap,
 716  * returns FALSE if there's an error creating a FIFO */
 717 gboolean
 718 extcap_init_interfaces(capture_options *capture_opts)
 719 {
 720     guint i;
 721     interface_options interface_opts;
 722
 723     for (i = 0; i < capture_opts->ifaces->len; i++)
 724     {
 725         GPtrArray *args = NULL;
 726         GPid pid = INVALID_EXTCAP_PID;
 727         gchar **tmp;
 728         int tmp_i;
 729
 730         interface_opts = g_array_index(capture_opts->ifaces, interface_options, i);
 731
 732         /* skip native interfaces */
 733         if (interface_opts.if_type != IF_EXTCAP )
 734             continue;
 735
 736         /* create pipe for fifo */
 737         if ( ! extcap_create_pipe ( &interface_opts.extcap_fifo ) )
 738             return FALSE;
 739
 740         /* Create extcap call */
 741         args = g_ptr_array_new();
 742 #define add_arg(X) g_ptr_array_add(args, g_strdup(X))
 743
 744         add_arg(interface_opts.extcap);
 745         add_arg(EXTCAP_ARGUMENT_RUN_CAPTURE);
 746         add_arg(EXTCAP_ARGUMENT_INTERFACE);
 747         add_arg(interface_opts.name);
 748         if (interface_opts.cfilter && strlen(interface_opts.cfilter) > 0) {
 749             add_arg(EXTCAP_ARGUMENT_CAPTURE_FILTER);
 750             add_arg(interface_opts.cfilter);
 751         }
 752         add_arg(EXTCAP_ARGUMENT_RUN_PIPE);
 753         add_arg(interface_opts.extcap_fifo);
 754         if (interface_opts.extcap_args == NULL || g_hash_table_size(interface_opts.extcap_args) == 0)
 755         {
 756             /* User did not perform interface configuration.
 757              *
 758              * Check if there are any boolean flags that are set by default
 759              * and hence their argument should be added.
 760              */
 761             GList *arglist;
 762             GList *elem;
 763
 764             arglist = extcap_get_if_configuration(interface_opts.name);
 765             for (elem = g_list_first(arglist); elem; elem = elem->next)
 766             {
 767                 GList * arg_list;
 768                 extcap_arg *arg_iter;
 769
 770                 if (elem->data == NULL)
 771                 {
 772                     continue;
 773                 }
 774
 775                 arg_list = g_list_first((GList *)elem->data);
 776                 while (arg_list != NULL) {
 777                     gchar * stored = NULL, * defval = NULL;
 778                     /* In case of boolflags only first element in arg_list is relevant. */
 779                     arg_iter = (extcap_arg*) (arg_list->data);
 780                     if ( arg_iter->storeval != NULL )
 781                         stored = arg_iter->storeval;
 782
 783                     if ( arg_iter->default_complex != NULL && arg_iter->default_complex->_val != NULL )
 784                         defval = arg_iter->default_complex->_val;
 785
 786                     /* Different data in storage then set for default */
 787                     if ( g_strcmp0(stored, defval) != 0 ) {
 788                         if ( arg_iter->arg_type == EXTCAP_ARG_BOOLFLAG ) {
 789                             if ( g_strcmp0(stored, "true") == 0 )
 790                                 add_arg(arg_iter->call);
 791                         } else {
 792                             gchar * call = g_strconcat(arg_iter->call, " ", stored, NULL);
 793                             add_arg(call);
 794                             g_free(call);
 795                         }
 796                     } else if  (arg_iter->arg_type == EXTCAP_ARG_BOOLFLAG) {
 797                         if (extcap_complex_get_bool(arg_iter->default_complex))
 798                             add_arg(arg_iter->call);
 799                     }
 800
 801                     arg_list = arg_list->next;
 802                 }
 803             }
 804
 805             extcap_free_if_configuration(arglist);
 806         }
 807         else
 808         {
 809             g_hash_table_foreach_remove(interface_opts.extcap_args, extcap_add_arg_and_remove_cb, args);
 810         }
 811         add_arg(NULL);
 812 #undef add_arg
 813
 814         /* Dump commandline parameters sent to extcap. */
 815         for (tmp = (gchar **)args->pdata, tmp_i = 0; *tmp && **tmp; ++tmp_i, ++tmp)
 816         {
 817             g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "argv[%d]: %s", tmp_i, *tmp);
 818         }
 819
 820         /* Wireshark for windows crashes here sometimes *
 821          * Access violation reading location 0x...      */
 822         g_spawn_async(NULL, (gchar **)args->pdata, NULL,
 823                     (GSpawnFlags) G_SPAWN_DO_NOT_REAP_CHILD, NULL, NULL,
 824                     &pid,NULL);
 825
 826         g_ptr_array_foreach(args, (GFunc)g_free, NULL);
 827         g_ptr_array_free(args, TRUE);
 828         interface_opts.extcap_pid = pid;
 829         interface_opts.extcap_child_watch =
 830             g_child_watch_add(pid, extcap_child_watch_cb, (gpointer)capture_opts);
 831         capture_opts->ifaces = g_array_remove_index(capture_opts->ifaces, i);
 832         g_array_insert_val(capture_opts->ifaces, i, interface_opts);
 833
 834 #ifdef _WIN32
 835         /* On Windows, wait for extcap to connect to named pipe.
 836          * Some extcaps will present UAC screen to user.
 837          * 30 second timeout should be reasonable timeout for extcap to
 838          * connect to named pipe (including user interaction).
 839          * Wait on multiple object in case of extcap termination
 840          * without opening pipe.
 841          *
 842          * Minimum supported version of Windows: XP / Server 2003.
 843          */
 844         if (pid != INVALID_EXTCAP_PID)
 845         {
 846             DWORD dw;
 847             HANDLE handles[2];
 848             OVERLAPPED ov;
 849             ov.Pointer = 0;
 850             ov.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
 851
 852             ConnectNamedPipe(pipe_h, &ov);
 853             handles[0] = ov.hEvent;
 854             handles[1] = pid;
 855
 856             if (GetLastError() == ERROR_PIPE_CONNECTED)
 857             {
 858                 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "extcap connected to pipe");
 859             }
 860             else
 861             {
 862                 dw = WaitForMultipleObjects(2, handles, FALSE, 30000);
 863                 if (dw == WAIT_OBJECT_0)
 864                 {
 865                     /* ConnectNamedPipe finished. */
 866                     DWORD code;
 867
 868                     code = GetLastError();
 869                     if (code == ERROR_IO_PENDING)
 870                     {
 871                         DWORD dummy;
 872                         if (!GetOverlappedResult(ov.hEvent, &ov, &dummy, TRUE))
 873                         {
 874                             code = GetLastError();
 875                         }
 876                         else
 877                         {
 878                             code = ERROR_SUCCESS;
 879                         }
 880                     }
 881
 882                     g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "ConnectNamedPipe code: %d", code);
 883                 }
 884                 else if (dw == (WAIT_OBJECT_0 + 1))
 885                 {
 886                     /* extcap process terminated. */
 887                     g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "extcap terminated without connecting to pipe!");
 888                 }
 889                 else if (dw == WAIT_TIMEOUT)
 890                 {
 891                     g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "extcap didn't connect to pipe within 30 seconds!");
 892                 }
 893                 else
 894                 {
 895                     g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "WaitForMultipleObjects returned 0x%08X. Error %d", dw, GetLastError());
 896                 }
 897             }
 898
 899             CloseHandle(ov.hEvent);
 900         }
 901 #endif
 902     }
 903
 904     return TRUE;
 905 }
 906
 907 #ifdef _WIN32
 908 /* called by capture_sync to get the CreatNamedPipe handle*/
 909 HANDLE
 910 extcap_get_win32_handle()
 911 {
 912     return pipe_h;
 913 }
 914 #endif
 915
 916 gboolean extcap_create_pipe(char ** fifo)
 917 {
 918 #ifdef _WIN32
 919     gchar timestr[ 14+1 ];
 920     time_t current_time;
 921
 922     gchar *pipename = NULL;
 923
 924     SECURITY_ATTRIBUTES security;
 925     /* create pipename */
 926     current_time = time(NULL);
 927     strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&current_time));
 928     pipename = g_strconcat ( "\\\\.\\pipe\\", EXTCAP_PIPE_PREFIX, "_", timestr, NULL );
 929
 930     /* Security struct to enable Inheritable HANDLE */
 931     memset(&security, 0, sizeof(SECURITY_ATTRIBUTES));
 932     security.nLength = sizeof(SECURITY_ATTRIBUTES);
 933     security.bInheritHandle = TRUE;
 934     security.lpSecurityDescriptor = NULL;
 935
 936     /* create a namedPipe*/
 937     pipe_h = CreateNamedPipe(
 938                 utf_8to16(pipename),
 939                 PIPE_ACCESS_DUPLEX | FILE_FLAG_OVERLAPPED,
 940                 PIPE_TYPE_MESSAGE| PIPE_READMODE_MESSAGE | PIPE_WAIT,
 941                 5, 65536, 65536,
 942                 300,
 943                 &security);
 944
 945     if (pipe_h == INVALID_HANDLE_VALUE)
 946     {
 947         g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,"\nError creating pipe => (%d)", GetLastError());
 948         return FALSE;
 949     }
 950     else
 951     {
 952         g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,"\nWireshark Created pipe =>(%s)",pipename);
 953         *fifo = g_strdup(pipename);
 954     }
 955 #else
 956     gchar *temp_name = NULL;
 957     int fd = 0;
 958
 959     if ((fd = create_tempfile(&temp_name, EXTCAP_PIPE_PREFIX)) < 0 )
 960         return FALSE;
 961
 962     ws_close(fd);
 963
 964     g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
 965             "Extcap - Creating fifo: %s", temp_name);
 966
 967     if ( file_exists(temp_name) )
 968         ws_unlink(temp_name);
 969
 970     if (mkfifo(temp_name, 0600) == 0)
 971         *fifo = g_strdup(temp_name);
 972 #endif
 973
 974     return TRUE;
 975 }
 976
 977 #if ARG_DEBUG
 978 void extcap_debug_arguments ( extcap_arg *arg_iter )
 979 {
 980     extcap_value *v = NULL;
 981     GList *walker = NULL;
 982
 983     printf("debug - parser dump\n");
 984     while (arg_iter != NULL) {
 985         printf("ARG %d call=%s display=\"%s\" type=", arg_iter->arg_num, arg_iter->call, arg_iter->display);
 986
 987         switch (arg_iter->arg_type) {
 988             case EXTCAP_ARG_INTEGER:
 989             printf("int\n");
 990             break;
 991             case EXTCAP_ARG_UNSIGNED:
 992             printf("unsigned\n");
 993             break;
 994             case EXTCAP_ARG_LONG:
 995             printf("long\n");
 996             break;
 997             case EXTCAP_ARG_DOUBLE:
 998             printf("double\n");
 999             break;
1000             case EXTCAP_ARG_BOOLEAN:
1001             printf("boolean\n");
1002             break;
1003             case EXTCAP_ARG_MENU:
1004             printf("menu\n");
1005             break;
1006             case EXTCAP_ARG_RADIO:
1007             printf("radio\n");
1008             break;
1009             case EXTCAP_ARG_SELECTOR:
1010             printf("selctor\n");
1011             break;
1012             case EXTCAP_ARG_STRING:
1013             printf ( "string\n" );
1014             break;
1015             case EXTCAP_ARG_PASSWORD:
1016             printf ( "PASSWORD\n" );
1017             break;
1018             case EXTCAP_ARG_MULTICHECK:
1019             printf ( "unknown\n" );
1020             break;
1021             case EXTCAP_ARG_UNKNOWN:
1022             printf ( "unknown\n" );
1023             break;
1024         }
1025
1026         if (arg_iter->range_start != NULL && arg_iter->range_end != NULL) {
1027             printf("\tRange: ");
1028             extcap_printf_complex(arg_iter->range_start);
1029             printf(" - ");
1030             extcap_printf_complex(arg_iter->range_end);
1031             printf("\n");
1032         }
1033
1034         for ( walker = g_list_first ( arg_iter->value_list ); walker; walker = walker->next )
1035         {
1036             v = (extcap_value *)walker->data;
1037             if (v->is_default)
1038             printf("*");
1039             printf("\tcall=\"%p\" display=\"%p\"\n", v->call, v->display);
1040             printf("\tcall=\"%s\" display=\"%s\"\n", v->call, v->display);
1041         }
1042
1043         arg_iter = arg_iter->next_arg;
1044     }
1045 }
1046 #endif
1047 #endif
1048
1049 /*
1050  * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
1051  *
1052  * Local variables:
1053  * c-basic-offset: 4
1054  * tab-width: 8
1055  * indent-tabs-mode: nil
1056  * End:
1057  *
1058  * vi: set shiftwidth=4 tabstop=8 expandtab:
1059  * :indentSize=4:tabSize=8:noTabs=true:
1060  */