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 #ifdef HAVE_SYS_TYPES_H
  41 #include <sys/types.h>
  42 #endif
  43 #ifdef HAVE_SYS_WAIT_H
  44 #include <sys/wait.h>
  45 #endif
  46
  47 #include <glib.h>
  48 #include <log.h>
  49
  50 #include <epan/prefs.h>
  51 #include <epan/prefs-int.h>
  52
  53 #include <wsutil/file_util.h>
  54 #include <wsutil/filesystem.h>
  55 #include <wsutil/tempfile.h>
  56
  57 #include "capture_opts.h"
  58
  59 #include "extcap.h"
  60 #include "extcap_parser.h"
  61 #include "extcap_spawn.h"
  62
  63 #ifdef _WIN32
  64 static HANDLE pipe_h = NULL;
  65 #endif
  66
  67 #define EXTCAP_PREF_SIZE 256
  68 static void extcap_child_watch_cb(GPid pid, gint status _U_, gpointer user_data);
  69
  70 /* internal container, for all the extcap interfaces that have been found.
  71  * will be resetted by every call to extcap_interface_list() and is being
  72  * used in extcap_get_if_* as well as extcap_init_interfaces to ensure,
  73  * that only extcap interfaces are being given to underlying extcap programs
  74  */
  75 static GHashTable *ifaces = NULL;
  76
  77 /* internal container, for all the extcap executables that have been found.
  78  * will be resetted by every call to extcap_interface_list() and is being
  79  * used for printing information about all extcap interfaces found
  80  */
  81 static GHashTable *tools = NULL;
  82
  83 /* internal container, to map preferences for extcap utilities to dynamic
  84  * memory content, which survives extcap if garbage collection, and does
  85  * not lead to dangling pointers
  86  */
  87 static GHashTable *extcap_prefs_dynamic_vals = NULL;
  88
  89 /* Callback definition for extcap_foreach */
  90 typedef gboolean (*extcap_cb_t)(const gchar *extcap, const gchar *ifname, gchar *output, void *data,
  91         gchar **err_str);
  92
  93 /* #define ARG_DEBUG */
  94 #if ARG_DEBUG
  95 static void extcap_debug_arguments ( extcap_arg *arg_iter );
  96 #endif
  97
  98 static gboolean
  99 extcap_if_exists(const gchar *ifname)
 100 {
 101     if ( !ifname || !ifaces )
 102         return FALSE;
 103
 104     if ( g_hash_table_lookup(ifaces, ifname) )
 105         return TRUE;
 106
 107     return FALSE;
 108 }
 109
 110 static gboolean
 111 extcap_if_exists_for_extcap(const gchar *ifname, const gchar *extcap)
 112 {
 113     gchar *entry = (gchar *)g_hash_table_lookup(ifaces, ifname);
 114
 115     if ( entry && strcmp(entry, extcap) == 0 )
 116         return TRUE;
 117
 118     return FALSE;
 119 }
 120
 121 static gchar *
 122 extcap_if_executable(const gchar *ifname)
 123 {
 124     return (gchar *)g_hash_table_lookup(ifaces, ifname);
 125 }
 126
 127 static void
 128 extcap_if_add(const gchar *ifname, const gchar *extcap)
 129 {
 130     if ( !g_hash_table_lookup(ifaces, ifname) )
 131         g_hash_table_insert(ifaces, g_strdup(ifname), g_strdup(extcap));
 132 }
 133
 134 static void
 135 extcap_free_info (gpointer data) {
 136     extcap_info * info = (extcap_info *)data;
 137
 138     g_free (info->basename);
 139     g_free (info->full_path);
 140     g_free (info->version);
 141     g_free (info);
 142 }
 143
 144 static void
 145 extcap_tool_add(const gchar *extcap, const extcap_interface *interface)
 146 {
 147     char *toolname;
 148
 149     if ( !extcap || !interface )
 150         return;
 151
 152     toolname = g_path_get_basename(extcap);
 153
 154     if ( !g_hash_table_lookup(tools, toolname) ) {
 155         extcap_info * store = (extcap_info *)g_new0(extcap_info, 1);
 156         store->version = g_strdup(interface->version);
 157         store->full_path = g_strdup(extcap);
 158         store->basename = g_strdup(toolname);
 159
 160         g_hash_table_insert(tools, g_strdup(toolname), store);
 161     }
 162
 163     g_free(toolname);
 164 }
 165
 166 /* Note: args does not need to be NULL-terminated. */
 167 static void extcap_foreach(gint argc, gchar **args, extcap_cb_t cb,
 168         void *cb_data, char **err_str, const char * ifname _U_) {
 169     const char *dirname = get_extcap_dir();
 170     GDir *dir;
 171     const gchar *file;
 172     gboolean keep_going;
 173
 174     keep_going = TRUE;
 175
 176     if ((dir = g_dir_open(dirname, 0, NULL)) != NULL) {
 177         GString *extcap_path = NULL;
 178
 179         extcap_path = g_string_new("");
 180         while (keep_going && (file = g_dir_read_name(dir)) != NULL ) {
 181             gchar *command_output = NULL;
 182
 183             /* full path to extcap binary */
 184 #ifdef _WIN32
 185             g_string_printf(extcap_path, "%s\\%s", dirname, file);
 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             if ( extcap_spawn_sync ( (gchar *) dirname, extcap_path->str, argc, args, &command_output ) )
 193                 keep_going = cb(extcap_path->str, ifname, command_output, cb_data, err_str);
 194
 195             g_free(command_output);
 196         }
 197
 198         g_dir_close(dir);
 199         g_string_free(extcap_path, TRUE);
 200     }
 201
 202 }
 203
 204 static gboolean dlt_cb(const gchar *extcap _U_, const gchar *ifname _U_, gchar *output, void *data,
 205         char **err_str) {
 206     extcap_token_sentence *tokens;
 207     extcap_dlt *dlts, *dlt_iter, *next;
 208     if_capabilities_t *caps;
 209     GList *linktype_list = NULL;
 210     data_link_info_t *data_link_info;
 211
 212     tokens = extcap_tokenize_sentences(output);
 213     extcap_parse_dlts(tokens, &dlts);
 214
 215     extcap_free_tokenized_sentence_list(tokens);
 216
 217     g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "Extcap pipe %s ", extcap);
 218
 219     /*
 220      * Allocate the interface capabilities structure.
 221      */
 222     caps = (if_capabilities_t *) g_malloc(sizeof *caps);
 223     caps->can_set_rfmon = FALSE;
 224
 225     dlt_iter = dlts;
 226     while (dlt_iter != NULL ) {
 227         g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
 228                 "  DLT %d name=\"%s\" display=\"%s\" ", dlt_iter->number,
 229                 dlt_iter->name, dlt_iter->display);
 230
 231         data_link_info = g_new(data_link_info_t, 1);
 232         data_link_info->dlt = dlt_iter->number;
 233         data_link_info->name = g_strdup(dlt_iter->name);
 234         data_link_info->description = g_strdup(dlt_iter->display);
 235         linktype_list = g_list_append(linktype_list, data_link_info);
 236         dlt_iter = dlt_iter->next_dlt;
 237     }
 238
 239     /* Check to see if we built a list */
 240     if (linktype_list != NULL && data != NULL) {
 241         caps->data_link_types = linktype_list;
 242         *(if_capabilities_t **) data = caps;
 243     } else {
 244         if (err_str) {
 245             g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "  returned no DLTs");
 246             *err_str = g_strdup("Extcap returned no DLTs");
 247         }
 248         g_free(caps);
 249     }
 250
 251     dlt_iter = dlts;
 252     while (dlt_iter != NULL ) {
 253         next = dlt_iter->next_dlt;
 254         extcap_free_dlt(dlt_iter);
 255         dlt_iter = next;
 256     }
 257
 258     return FALSE;
 259 }
 260
 261 if_capabilities_t *
 262 extcap_get_if_dlts(const gchar *ifname, char **err_str) {
 263     gchar *argv[3];
 264     gint i;
 265     if_capabilities_t *caps = NULL;
 266
 267     if (err_str != NULL)
 268         *err_str = NULL;
 269
 270     if ( extcap_if_exists(ifname) )
 271     {
 272         argv[0] = g_strdup(EXTCAP_ARGUMENT_LIST_DLTS);
 273         argv[1] = g_strdup(EXTCAP_ARGUMENT_INTERFACE);
 274         argv[2] = g_strdup(ifname);
 275
 276         extcap_foreach(3, argv, dlt_cb, &caps, err_str, ifname);
 277
 278         for (i = 0; i < 3; ++i)
 279             g_free(argv[i]);
 280     }
 281
 282     return caps;
 283 }
 284
 285 static gboolean interfaces_cb(const gchar *extcap, const gchar *ifname _U_, gchar *output, void *data,
 286         char **err_str _U_) {
 287     GList **il = (GList **) data;
 288     extcap_token_sentence *tokens;
 289     extcap_interface *interfaces, *int_iter; /*, *next; */
 290     if_info_t *if_info;
 291
 292     tokens = extcap_tokenize_sentences(output);
 293     extcap_parse_interfaces(tokens, &interfaces);
 294
 295     extcap_free_tokenized_sentence_list(tokens);
 296
 297     g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "Extcap pipe %s ", extcap);
 298
 299     int_iter = interfaces;
 300     while (int_iter != NULL ) {
 301         if ( int_iter->if_type == EXTCAP_SENTENCE_INTERFACE && extcap_if_exists(int_iter->call) )
 302         {
 303             g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_WARNING, "Extcap interface \"%s\" is already provided by \"%s\" ",
 304                     int_iter->call, (gchar *)extcap_if_executable(int_iter->call) );
 305             int_iter = int_iter->next_interface;
 306             continue;
 307         }
 308
 309         if ( int_iter->if_type == EXTCAP_SENTENCE_INTERFACE )
 310             g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "  Interface [%s] \"%s\" ",
 311                     int_iter->call, int_iter->display);
 312         else if ( int_iter->if_type == EXTCAP_SENTENCE_EXTCAP )
 313             g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "  Extcap [%s] ", int_iter->call);
 314
 315         if ( int_iter->if_type == EXTCAP_SENTENCE_INTERFACE ) {
 316             if (il != NULL) {
 317                 if_info = g_new0(if_info_t, 1);
 318                 if_info->name = g_strdup(int_iter->call);
 319                 if_info->friendly_name = g_strdup(int_iter->display);
 320
 321                 if_info->type = IF_EXTCAP;
 322
 323                 if_info->extcap = g_strdup(extcap);
 324                 *il = g_list_append(*il, if_info);
 325             }
 326
 327             extcap_if_add(int_iter->call, extcap);
 328         }
 329
 330         /* Call for interfaces and tools alike. Multiple calls (because a tool has multiple
 331          * interfaces) are handled internally */
 332         extcap_tool_add(extcap, int_iter);
 333
 334         int_iter = int_iter->next_interface;
 335     }
 336     extcap_free_interface(interfaces);
 337
 338     return TRUE;
 339 }
 340
 341 static gint
 342 if_info_compare(gconstpointer a, gconstpointer b)
 343 {
 344     gint comp = 0;
 345     const if_info_t * if_a = (const if_info_t *)a;
 346     const if_info_t * if_b = (const if_info_t *)b;
 347
 348     if ( (comp = g_strcmp0(if_a->name, if_b->name)) == 0 )
 349         return g_strcmp0(if_a->friendly_name, if_b->friendly_name);
 350
 351     return comp;
 352 }
 353
 354 static void
 355 extcap_reload_interface_list(GList **retp, char **err_str) {
 356     gchar *argv;
 357
 358     if (err_str != NULL)
 359         *err_str = NULL;
 360
 361     /* ifaces is used as cache, do not destroy its contents when
 362      * returning or no extcap interfaces can be queried for options */
 363     if (ifaces == NULL)
 364         ifaces = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, g_free);
 365     else
 366         g_hash_table_remove_all(ifaces);
 367
 368     if (tools == NULL)
 369         tools = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, extcap_free_info);
 370     else
 371         g_hash_table_remove_all(tools);
 372
 373     argv = g_strdup(EXTCAP_ARGUMENT_LIST_INTERFACES);
 374
 375     extcap_foreach(1, &argv, interfaces_cb, retp, err_str, NULL);
 376
 377     g_free(argv);
 378 }
 379
 380 GHashTable *
 381 extcap_tools_list(void) {
 382     if ( tools == NULL || g_hash_table_size(tools) == 0 )
 383         extcap_reload_interface_list(NULL, NULL);
 384
 385     return tools;
 386 }
 387
 388 GList *
 389 append_extcap_interface_list(GList *list, char **err_str) {
 390     GList *ret = NULL;
 391     GList *entry;
 392     void *data;
 393
 394     /* Update the extcap interfaces and get a list of their if_infos */
 395     extcap_reload_interface_list(&ret, err_str);
 396
 397     /* Sort that list */
 398     ret = g_list_sort(ret, if_info_compare);
 399
 400     /* Append the interfaces in that list to the list we're handed. */
 401     while (ret != NULL) {
 402         entry = g_list_first(ret);
 403         data = entry->data;
 404         ret = g_list_delete_link(ret, entry);
 405         list = g_list_append(list, data);
 406     }
 407     return list;
 408 }
 409
 410 static void extcap_free_arg_elem(gpointer data, gpointer user_data _U_) {
 411     extcap_free_arg((extcap_arg *) data);
 412     g_free(data);
 413 }
 414
 415 void extcap_register_preferences(void)
 416 {
 417     GList * interfaces = NULL;
 418
 419     module_t * dev_module = prefs_find_module("extcap");
 420
 421     if ( !dev_module )
 422         return;
 423
 424     if ( ! ifaces || g_hash_table_size(ifaces) == 0 )
 425         extcap_reload_interface_list(NULL, NULL);
 426
 427     interfaces = g_hash_table_get_keys(ifaces);
 428
 429     while ( interfaces ) {
 430         extcap_get_if_configuration((gchar *)interfaces->data);
 431
 432         interfaces = g_list_next(interfaces);
 433     }
 434 }
 435
 436 void extcap_cleanup(void)
 437 {
 438     if (extcap_prefs_dynamic_vals) {
 439         g_hash_table_destroy(extcap_prefs_dynamic_vals);
 440     }
 441 }
 442
 443 void extcap_pref_store(extcap_arg * arg, const char * newval)
 444 {
 445     if (arg && arg->storeval != NULL)
 446     {
 447         memset(arg->storeval, 0, EXTCAP_PREF_SIZE * sizeof(char));
 448         if ( newval )
 449             g_snprintf(arg->storeval, EXTCAP_PREF_SIZE, "%s", newval);
 450     }
 451
 452 }
 453
 454 static gchar * extcap_prefs_dynamic_valptr(const char *name)
 455 {
 456     gchar *valp;
 457     if (!extcap_prefs_dynamic_vals) {
 458         /* Initialize table only as needed, most preferences are not dynamic */
 459         extcap_prefs_dynamic_vals = g_hash_table_new_full(g_str_hash, g_str_equal,
 460                 g_free, g_free);
 461     }
 462     valp = (gchar *)g_hash_table_lookup(extcap_prefs_dynamic_vals, name);
 463     if (!valp) {
 464         /* New dynamic pref, allocate, initialize and store. */
 465         valp = g_new0(gchar, EXTCAP_PREF_SIZE);
 466         g_hash_table_insert(extcap_prefs_dynamic_vals, g_strdup(name), valp);
 467     }
 468     return valp;
 469 }
 470
 471 static void extcap_free_if_configuration(GList *list)
 472 {
 473     GList *elem, *sl;
 474
 475     for (elem = g_list_first(list); elem; elem = elem->next)
 476     {
 477         if (elem->data != NULL) {
 478             /* g_list_free_full() only exists since 2.28. */
 479             sl = g_list_first((GList *)elem->data);
 480             g_list_foreach(sl, (GFunc)extcap_free_arg_elem, NULL);
 481             g_list_free(sl);
 482         }
 483     }
 484     g_list_free(list);
 485 }
 486
 487 struct preference *
 488 extcap_pref_for_argument(const gchar *ifname, struct _extcap_arg * arg) {
 489     struct preference * pref = NULL;
 490
 491     GRegex * regex_name = g_regex_new ("[-]+", (GRegexCompileFlags) 0, (GRegexMatchFlags) 0, NULL );
 492     GRegex * regex_ifname = g_regex_new ("(?![a-zA-Z1-9_]).", (GRegexCompileFlags) 0, (GRegexMatchFlags) 0, NULL );
 493     if (regex_name && regex_ifname) {
 494         if ( prefs_find_module("extcap") ) {
 495             gchar * pref_name = g_regex_replace(regex_name, arg->call, strlen(arg->call), 0, "", (GRegexMatchFlags) 0, NULL );
 496             gchar * ifname_underscore = g_regex_replace(regex_ifname, ifname, strlen(ifname), 0, "_", (GRegexMatchFlags) 0, NULL );
 497             gchar * ifname_lowercase = g_ascii_strdown(ifname_underscore, -1);
 498             gchar * pref_ifname = g_strconcat(ifname_lowercase, ".", pref_name, NULL);
 499
 500             pref = prefs_find_preference(prefs_find_module("extcap"), pref_ifname);
 501
 502             g_free(pref_name);
 503             g_free(ifname_underscore);
 504             g_free(ifname_lowercase);
 505             g_free(pref_ifname);
 506         }
 507     }
 508     if (regex_name) {
 509         g_regex_unref(regex_name);
 510     }
 511     if (regex_ifname) {
 512         g_regex_unref(regex_ifname);
 513     }
 514
 515     return pref;
 516 }
 517
 518 static gboolean search_cb(const gchar *extcap _U_, const gchar *ifname _U_, gchar *output, void *data,
 519         char **err_str _U_) {
 520     extcap_token_sentence *tokens = NULL;
 521     GList *arguments = NULL;
 522     GList **il = (GList **) data;
 523     module_t * dev_module = NULL;
 524
 525     tokens = extcap_tokenize_sentences(output);
 526     arguments = extcap_parse_args(tokens);
 527
 528     extcap_free_tokenized_sentence_list(tokens);
 529
 530 #if ARG_DEBUG
 531     extcap_debug_arguments ( arguments );
 532 #endif
 533
 534     dev_module = prefs_find_module("extcap");
 535
 536     if ( dev_module ) {
 537         GList * walker = arguments;
 538
 539         GRegex * regex_name = g_regex_new ("[-]+", (GRegexCompileFlags) 0, (GRegexMatchFlags) 0, NULL );
 540         GRegex * regex_ifname = g_regex_new ("(?![a-zA-Z1-9_]).", (GRegexCompileFlags) 0, (GRegexMatchFlags) 0, NULL );
 541         if (regex_name && regex_ifname) {
 542             while ( walker != NULL ) {
 543                 extcap_arg * arg = (extcap_arg *)walker->data;
 544                 arg->device_name = g_strdup(ifname);
 545
 546                 if ( arg->save ) {
 547                     struct preference * pref = NULL;
 548
 549                     gchar * pref_name = g_regex_replace(regex_name, arg->call, strlen(arg->call), 0, "", (GRegexMatchFlags) 0, NULL );
 550                     gchar * ifname_underscore = g_regex_replace(regex_ifname, ifname, strlen(ifname), 0, "_", (GRegexMatchFlags) 0, NULL );
 551                     gchar * ifname_lowercase = g_ascii_strdown(ifname_underscore, -1);
 552                     gchar * pref_ifname = g_strconcat(ifname_lowercase, ".", pref_name, NULL);
 553
 554                     if ( ( pref = prefs_find_preference(dev_module, pref_ifname) ) == NULL ) {
 555                         /* Set an initial value */
 556                         if ( ! arg->storeval && arg->default_complex )
 557                         {
 558                             arg->storeval = extcap_prefs_dynamic_valptr(pref_ifname);
 559                             g_snprintf(arg->storeval, EXTCAP_PREF_SIZE, "%s", arg->default_complex->_val);
 560                         }
 561
 562                         prefs_register_string_preference(dev_module, g_strdup(pref_ifname),
 563                                 arg->display, arg->display, (const gchar **)&(arg->storeval));
 564                     } else {
 565                         /* Been here before, restore stored value */
 566                         if (! arg->storeval && pref->varp.string)
 567                         {
 568                             arg->storeval = extcap_prefs_dynamic_valptr(pref_ifname);
 569                             g_snprintf(arg->storeval, EXTCAP_PREF_SIZE, "%s", *(pref->varp.string));
 570                         }
 571                     }
 572
 573                     g_free(pref_name);
 574                     g_free(ifname_underscore);
 575                     g_free(ifname_lowercase);
 576                     g_free(pref_ifname);
 577                 }
 578
 579                 walker = g_list_next(walker);
 580             }
 581         }
 582         if (regex_name) {
 583             g_regex_unref(regex_name);
 584         }
 585         if (regex_ifname) {
 586             g_regex_unref(regex_ifname);
 587         }
 588     }
 589
 590     *il = g_list_append(*il, arguments);
 591
 592     /* By returning false, extcap_foreach will break on first found */
 593     return TRUE;
 594 }
 595
 596 GList *
 597 extcap_get_if_configuration(const char * ifname) {
 598     gchar *argv[3];
 599     GList *ret = NULL;
 600     gchar **err_str = NULL;
 601     int i;
 602
 603     if ( extcap_if_exists(ifname) )
 604     {
 605         g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "Extcap path %s",
 606                 get_extcap_dir());
 607
 608         argv[0] = g_strdup(EXTCAP_ARGUMENT_CONFIG);
 609         argv[1] = g_strdup(EXTCAP_ARGUMENT_INTERFACE);
 610         argv[2] = g_strdup(ifname);
 611
 612         extcap_foreach(3, argv, search_cb, &ret, err_str, ifname);
 613
 614         for (i = 0; i < 3; i++)
 615             g_free(argv[i]);
 616     }
 617
 618     return ret;
 619 }
 620
 621 gboolean
 622 extcap_has_configuration(const char * ifname, gboolean is_required) {
 623     GList * arguments = 0;
 624     GList * walker = 0, * item = 0;
 625
 626     gboolean found = FALSE;
 627
 628     arguments = extcap_get_if_configuration((const char *)( ifname ) );
 629     walker = g_list_first(arguments);
 630
 631     while ( walker != NULL && ! found ) {
 632         item = g_list_first((GList *)(walker->data));
 633         while ( item != NULL && ! found ) {
 634             if ( (extcap_arg *)(item->data) != NULL ) {
 635                 extcap_arg * arg = (extcap_arg *)(item->data);
 636                 /* Should required options be present, or any kind of options */
 637                 if ( ! is_required )
 638                     found = TRUE;
 639                 else if ( arg->is_required ) {
 640                     gchar * stored = NULL;
 641                     gchar * defval = NULL;
 642
 643                     if ( arg->storeval != NULL )
 644                         stored = arg->storeval;
 645
 646                     if ( arg->default_complex != NULL && arg->default_complex->_val != NULL )
 647                         defval = arg->default_complex->_val;
 648
 649                     if ( arg->is_required ) {
 650                         /* If stored and defval is identical and the argument is required,
 651                          * configuration is needed */
 652                         if ( defval && stored && g_strcmp0(stored, defval) == 0 )
 653                             found = TRUE;
 654                         else if ( ! defval && (!stored || strlen(g_strchomp(stored)) <= (size_t)0) )
 655                             found = TRUE;
 656                     }
 657
 658                     if ( arg->arg_type == EXTCAP_ARG_FILESELECT ) {
 659                         if ( arg->fileexists && ! ( file_exists(defval) || file_exists(stored) ) )
 660                             found = TRUE;
 661                     }
 662                 }
 663             }
 664
 665             item = item->next;
 666         }
 667         walker = walker->next;
 668     }
 669     extcap_free_if_configuration(arguments);
 670
 671     return found;
 672 }
 673
 674 /* taken from capchild/capture_sync.c */
 675 static gboolean pipe_data_available(int pipe_fd) {
 676 #ifdef _WIN32 /* PeekNamedPipe */
 677     HANDLE hPipe = (HANDLE) _get_osfhandle(pipe_fd);
 678     DWORD bytes_avail;
 679
 680     if (hPipe == INVALID_HANDLE_VALUE)
 681         return FALSE;
 682
 683     if (! PeekNamedPipe(hPipe, NULL, 0, NULL, &bytes_avail, NULL))
 684         return FALSE;
 685
 686     if (bytes_avail > 0)
 687         return TRUE;
 688     return FALSE;
 689 #else /* select */
 690     fd_set rfds;
 691     struct timeval timeout;
 692
 693     FD_ZERO(&rfds);
 694     FD_SET(pipe_fd, &rfds);
 695     timeout.tv_sec = 0;
 696     timeout.tv_usec = 0;
 697
 698     if (select(pipe_fd+1, &rfds, NULL, NULL, &timeout) > 0)
 699         return TRUE;
 700
 701     return FALSE;
 702 #endif
 703 }
 704
 705 void extcap_if_cleanup(capture_options * capture_opts, gchar ** errormsg) {
 706     interface_options interface_opts;
 707     extcap_userdata * userdata;
 708     guint icnt = 0;
 709     gboolean overwrite_exitcode;
 710     gchar * buffer;
 711 #define STDERR_BUFFER_SIZE 1024
 712
 713     for (icnt = 0; icnt < capture_opts->ifaces->len; icnt++) {
 714         interface_opts = g_array_index(capture_opts->ifaces, interface_options,
 715                 icnt);
 716
 717         /* skip native interfaces */
 718         if (interface_opts.if_type != IF_EXTCAP)
 719             continue;
 720
 721         overwrite_exitcode = FALSE;
 722
 723         g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
 724                 "Extcap [%s] - Cleaning up fifo: %s; PID: %d", interface_opts.name,
 725                 interface_opts.extcap_fifo, interface_opts.extcap_pid);
 726 #ifdef _WIN32
 727         if (pipe_h)
 728         {
 729             g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
 730                 "Extcap [%s] - Closing pipe", interface_opts.name);
 731             FlushFileBuffers(pipe_h);
 732             DisconnectNamedPipe(pipe_h);
 733             CloseHandle(pipe_h);
 734         }
 735 #else
 736         if (interface_opts.extcap_fifo != NULL && file_exists(interface_opts.extcap_fifo))
 737         {
 738             /* the fifo will not be freed here, but with the other capture_opts in capture_sync */
 739             ws_unlink(interface_opts.extcap_fifo);
 740             interface_opts.extcap_fifo = NULL;
 741         }
 742 #endif
 743         /* Maybe the client closed and removed fifo, but ws should check if
 744          * pid should be closed */
 745         g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
 746                 "Extcap [%s] - Closing spawned PID: %d", interface_opts.name,
 747                 interface_opts.extcap_pid);
 748
 749         userdata = (extcap_userdata *) interface_opts.extcap_userdata;
 750         if ( userdata )
 751         {
 752             if (userdata->extcap_stderr_rd > 0 && pipe_data_available(userdata->extcap_stderr_rd) )
 753             {
 754                 buffer = (gchar * )g_malloc0(sizeof(gchar) * STDERR_BUFFER_SIZE + 1);
 755 #ifdef _WIN32
 756                 win32_readfrompipe((HANDLE)_get_osfhandle(userdata->extcap_stderr_rd), STDERR_BUFFER_SIZE, buffer);
 757 #else
 758                 if (read(userdata->extcap_stderr_rd, buffer, sizeof(gchar) * STDERR_BUFFER_SIZE) <= 0 )
 759                     buffer[0] = '\0';
 760 #endif
 761                 if ( strlen ( buffer) > 0 )
 762                 {
 763                     userdata->extcap_stderr = g_strdup_printf("%s", buffer);
 764                     userdata->exitcode = 1;
 765                 }
 766                 g_free(buffer);
 767             }
 768
 769 #ifndef _WIN32
 770             /* Final child watch may not have been called */
 771             if ( interface_opts.extcap_child_watch != 0 )
 772             {
 773                 extcap_child_watch_cb(userdata->pid, 0, capture_opts);
 774                 /* it will have changed in extcap_child_watch_cb */
 775                 interface_opts = g_array_index(capture_opts->ifaces, interface_options,
 776                                 icnt);
 777             }
 778 #endif
 779
 780             if ( userdata->extcap_stderr != NULL )
 781                 overwrite_exitcode = TRUE;
 782
 783             if ( overwrite_exitcode || userdata->exitcode != 0 )
 784             {
 785                 if ( userdata->extcap_stderr != 0 )
 786                 {
 787                     if ( *errormsg == NULL )
 788                         *errormsg = g_strdup_printf("Error by extcap pipe: %s", userdata->extcap_stderr);
 789                     else
 790                     {
 791                         gchar * temp = g_strconcat ( *errormsg, "\nError by extcap pipe: " ,userdata->extcap_stderr, NULL );
 792                         g_free(*errormsg);
 793                         *errormsg = temp;
 794                     }
 795                     g_free (userdata->extcap_stderr );
 796                 }
 797
 798                 userdata->extcap_stderr = NULL;
 799                 userdata->exitcode = 0;
 800             }
 801         }
 802
 803         if (interface_opts.extcap_child_watch > 0)
 804         {
 805             g_source_remove(interface_opts.extcap_child_watch);
 806             interface_opts.extcap_child_watch = 0;
 807         }
 808
 809         if (interface_opts.extcap_pid != INVALID_EXTCAP_PID)
 810         {
 811 #ifdef _WIN32
 812             TerminateProcess(interface_opts.extcap_pid, 0);
 813 #endif
 814             g_spawn_close_pid(interface_opts.extcap_pid);
 815             interface_opts.extcap_pid = INVALID_EXTCAP_PID;
 816
 817             g_free(interface_opts.extcap_userdata);
 818             interface_opts.extcap_userdata = NULL;
 819         }
 820
 821         /* Make sure modified interface_opts is saved in capture_opts. */
 822         capture_opts->ifaces = g_array_remove_index(capture_opts->ifaces, icnt);
 823         g_array_insert_val(capture_opts->ifaces, icnt, interface_opts);
 824     }
 825 }
 826
 827 static gboolean
 828 extcap_add_arg_and_remove_cb(gpointer key, gpointer value, gpointer data) {
 829     GPtrArray *args = (GPtrArray *)data;
 830
 831     if ( key != NULL )
 832     {
 833         g_ptr_array_add(args, g_strdup((const gchar*)key));
 834
 835         if ( value != NULL )
 836             g_ptr_array_add(args, g_strdup((const gchar*)value));
 837
 838         return TRUE;
 839     }
 840
 841     return FALSE;
 842 }
 843
 844 void extcap_child_watch_cb(GPid pid, gint status _U_, gpointer user_data)
 845 {
 846     guint i;
 847     interface_options interface_opts;
 848     extcap_userdata * userdata = NULL;
 849     capture_options * capture_opts = (capture_options *)(user_data);
 850
 851     if ( capture_opts == NULL || capture_opts->ifaces == NULL || capture_opts->ifaces->len == 0 )
 852         return;
 853
 854     /* Close handle to child process. */
 855     g_spawn_close_pid(pid);
 856
 857     /* Update extcap_pid in interface options structure. */
 858     for (i = 0; i < capture_opts->ifaces->len; i++)
 859     {
 860         interface_opts = g_array_index(capture_opts->ifaces, interface_options, i);
 861         if (interface_opts.extcap_pid == pid)
 862         {
 863             userdata = (extcap_userdata *)interface_opts.extcap_userdata;
 864             if ( userdata != NULL )
 865             {
 866                 interface_opts.extcap_pid = INVALID_EXTCAP_PID;
 867                 userdata->exitcode = 0;
 868 #ifndef _WIN32
 869                 if ( WIFEXITED(status) )
 870                 {
 871                     if ( WEXITSTATUS(status) != 0 )
 872                         userdata->exitcode = WEXITSTATUS(status);
 873                 }
 874                 else
 875                     userdata->exitcode = G_SPAWN_ERROR_FAILED;
 876 #else
 877                 if (status != 0)
 878                     userdata->exitcode = status;
 879 #endif
 880                 if ( status == 0 && userdata->extcap_stderr != NULL )
 881                     userdata->exitcode = 1;
 882             }
 883             g_source_remove(interface_opts.extcap_child_watch);
 884             interface_opts.extcap_child_watch = 0;
 885
 886             capture_opts->ifaces = g_array_remove_index(capture_opts->ifaces, i);
 887             g_array_insert_val(capture_opts->ifaces, i, interface_opts);
 888             break;
 889         }
 890     }
 891 }
 892
 893 static
 894 GPtrArray * extcap_prepare_arguments(interface_options interface_opts)
 895 {
 896     GPtrArray *result = NULL;
 897 #if ARG_DEBUG
 898     gchar **tmp;
 899     int tmp_i;
 900 #endif
 901
 902     if (interface_opts.if_type == IF_EXTCAP )
 903     {
 904         result = g_ptr_array_new();
 905
 906 #define add_arg(X) g_ptr_array_add(result, g_strdup(X))
 907
 908         add_arg(interface_opts.extcap);
 909         add_arg(EXTCAP_ARGUMENT_RUN_CAPTURE);
 910         add_arg(EXTCAP_ARGUMENT_INTERFACE);
 911         add_arg(interface_opts.name);
 912         if (interface_opts.cfilter && strlen(interface_opts.cfilter) > 0) {
 913             add_arg(EXTCAP_ARGUMENT_CAPTURE_FILTER);
 914             add_arg(interface_opts.cfilter);
 915         }
 916         add_arg(EXTCAP_ARGUMENT_RUN_PIPE);
 917         add_arg(interface_opts.extcap_fifo);
 918         if (interface_opts.extcap_args == NULL || g_hash_table_size(interface_opts.extcap_args) == 0)
 919         {
 920             /* User did not perform interface configuration.
 921              *
 922              * Check if there are any boolean flags that are set by default
 923              * and hence their argument should be added.
 924              */
 925             GList *arglist;
 926             GList *elem;
 927
 928             arglist = extcap_get_if_configuration(interface_opts.name);
 929             for (elem = g_list_first(arglist); elem; elem = elem->next)
 930             {
 931                 GList * arg_list;
 932                 extcap_arg *arg_iter;
 933
 934                 if (elem->data == NULL)
 935                 {
 936                     continue;
 937                 }
 938
 939                 arg_list = g_list_first((GList *)elem->data);
 940                 while (arg_list != NULL) {
 941                     gchar * stored = NULL, * defval = NULL;
 942                     /* In case of boolflags only first element in arg_list is relevant. */
 943                     arg_iter = (extcap_arg*) (arg_list->data);
 944                     if ( arg_iter->storeval != NULL )
 945                         stored = arg_iter->storeval;
 946
 947                     if ( arg_iter->default_complex != NULL && arg_iter->default_complex->_val != NULL )
 948                         defval = arg_iter->default_complex->_val;
 949
 950                     /* Different data in storage then set for default */
 951                     if ( g_strcmp0(stored, defval) != 0 ) {
 952                         if ( arg_iter->arg_type == EXTCAP_ARG_BOOLFLAG ) {
 953                             if ( g_strcmp0(stored, "true") == 0 )
 954                                 add_arg(arg_iter->call);
 955                         } else {
 956                             gchar * call = g_strconcat(arg_iter->call, " ", stored, NULL);
 957                             add_arg(call);
 958                             g_free(call);
 959                         }
 960                     } else if  (arg_iter->arg_type == EXTCAP_ARG_BOOLFLAG) {
 961                         if (extcap_complex_get_bool(arg_iter->default_complex))
 962                             add_arg(arg_iter->call);
 963                     }
 964
 965                     arg_list = arg_list->next;
 966                 }
 967             }
 968
 969             extcap_free_if_configuration(arglist);
 970         }
 971         else
 972         {
 973             g_hash_table_foreach_remove(interface_opts.extcap_args, extcap_add_arg_and_remove_cb, result);
 974         }
 975         add_arg(NULL);
 976 #undef add_arg
 977
 978 #if ARG_DEBUG
 979         /* Dump commandline parameters sent to extcap. */
 980         for (tmp = (gchar **)result->pdata, tmp_i = 0; *tmp && **tmp; ++tmp_i, ++tmp)
 981         {
 982             g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "argv[%d]: %s", tmp_i, *tmp);
 983         }
 984 #endif
 985
 986     }
 987
 988     return result;
 989 }
 990
 991 /* call mkfifo for each extcap,
 992  * returns FALSE if there's an error creating a FIFO */
 993 gboolean
 994 extcap_init_interfaces(capture_options *capture_opts)
 995 {
 996     guint i;
 997     interface_options interface_opts;
 998     extcap_userdata * userdata;
 999
1000     for (i = 0; i < capture_opts->ifaces->len; i++)
1001     {
1002         GPtrArray *args = NULL;
1003         GPid pid = INVALID_EXTCAP_PID;
1004
1005         interface_opts = g_array_index(capture_opts->ifaces, interface_options, i);
1006
1007         /* skip native interfaces */
1008         if (interface_opts.if_type != IF_EXTCAP )
1009             continue;
1010
1011         /* create pipe for fifo */
1012         if ( ! extcap_create_pipe ( &interface_opts.extcap_fifo ) )
1013             return FALSE;
1014
1015         /* Create extcap call */
1016         args = extcap_prepare_arguments(interface_opts);
1017
1018         userdata = g_new0(extcap_userdata, 1);
1019
1020         pid = extcap_spawn_async(userdata, args );
1021
1022         g_ptr_array_foreach(args, (GFunc)g_free, NULL);
1023         g_ptr_array_free(args, TRUE);
1024
1025         if ( pid == INVALID_EXTCAP_PID )
1026         {
1027             g_free(userdata);
1028             continue;
1029         }
1030
1031         interface_opts.extcap_pid = pid;
1032
1033         interface_opts.extcap_child_watch =
1034             g_child_watch_add(pid, extcap_child_watch_cb, (gpointer)capture_opts);
1035
1036 #ifdef _WIN32
1037         /* On Windows, wait for extcap to connect to named pipe.
1038          * Some extcaps will present UAC screen to user.
1039          * 30 second timeout should be reasonable timeout for extcap to
1040          * connect to named pipe (including user interaction).
1041          * Wait on multiple object in case of extcap termination
1042          * without opening pipe.
1043          *
1044          * Minimum supported version of Windows: XP / Server 2003.
1045          */
1046         if (pid != INVALID_EXTCAP_PID)
1047         {
1048             extcap_wait_for_pipe(pipe_h, pid);
1049         }
1050
1051 #endif
1052
1053         interface_opts.extcap_userdata = (gpointer) userdata;
1054
1055         capture_opts->ifaces = g_array_remove_index(capture_opts->ifaces, i);
1056         g_array_insert_val(capture_opts->ifaces, i, interface_opts);
1057     }
1058
1059     return TRUE;
1060 }
1061
1062 #ifdef _WIN32
1063 /* called by capture_sync to get the CreatNamedPipe handle*/
1064 HANDLE
1065 extcap_get_win32_handle()
1066 {
1067     return pipe_h;
1068 }
1069 #endif
1070
1071 gboolean extcap_create_pipe(char ** fifo)
1072 {
1073 #ifdef _WIN32
1074     gchar timestr[ 14+1 ];
1075     time_t current_time;
1076
1077     gchar *pipename = NULL;
1078
1079     SECURITY_ATTRIBUTES security;
1080     /* create pipename */
1081     current_time = time(NULL);
1082     strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&current_time));
1083     pipename = g_strconcat ( "\\\\.\\pipe\\", EXTCAP_PIPE_PREFIX, "_", timestr, NULL );
1084
1085     /* Security struct to enable Inheritable HANDLE */
1086     memset(&security, 0, sizeof(SECURITY_ATTRIBUTES));
1087     security.nLength = sizeof(SECURITY_ATTRIBUTES);
1088     security.bInheritHandle = TRUE;
1089     security.lpSecurityDescriptor = NULL;
1090
1091     /* create a namedPipe*/
1092     pipe_h = CreateNamedPipe(
1093                 utf_8to16(pipename),
1094                 PIPE_ACCESS_DUPLEX | FILE_FLAG_OVERLAPPED,
1095                 PIPE_TYPE_MESSAGE| PIPE_READMODE_MESSAGE | PIPE_WAIT,
1096                 5, 65536, 65536,
1097                 300,
1098                 &security);
1099
1100     if (pipe_h == INVALID_HANDLE_VALUE)
1101     {
1102         g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,"\nError creating pipe => (%d)", GetLastError());
1103         return FALSE;
1104     }
1105     else
1106     {
1107         g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,"\nWireshark Created pipe =>(%s)",pipename);
1108         *fifo = g_strdup(pipename);
1109     }
1110 #else
1111     gchar *temp_name = NULL;
1112     int fd = 0;
1113
1114     if ((fd = create_tempfile(&temp_name, EXTCAP_PIPE_PREFIX, NULL)) < 0 )
1115         return FALSE;
1116
1117     ws_close(fd);
1118
1119     g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
1120             "Extcap - Creating fifo: %s", temp_name);
1121
1122     if ( file_exists(temp_name) )
1123         ws_unlink(temp_name);
1124
1125     if (mkfifo(temp_name, 0600) == 0)
1126         *fifo = g_strdup(temp_name);
1127 #endif
1128
1129     return TRUE;
1130 }
1131
1132 #if ARG_DEBUG
1133 void extcap_debug_arguments ( extcap_arg *arg_iter )
1134 {
1135     extcap_value *v = NULL;
1136     GList *walker = NULL;
1137
1138     printf("debug - parser dump\n");
1139     while (arg_iter != NULL) {
1140         printf("ARG %d call=%s display=\"%s\" type=", arg_iter->arg_num, arg_iter->call, arg_iter->display);
1141
1142         switch (arg_iter->arg_type) {
1143             case EXTCAP_ARG_INTEGER:
1144             printf("int\n");
1145             break;
1146             case EXTCAP_ARG_UNSIGNED:
1147             printf("unsigned\n");
1148             break;
1149             case EXTCAP_ARG_LONG:
1150             printf("long\n");
1151             break;
1152             case EXTCAP_ARG_DOUBLE:
1153             printf("double\n");
1154             break;
1155             case EXTCAP_ARG_BOOLEAN:
1156             printf("boolean\n");
1157             break;
1158             case EXTCAP_ARG_MENU:
1159             printf("menu\n");
1160             break;
1161             case EXTCAP_ARG_RADIO:
1162             printf("radio\n");
1163             break;
1164             case EXTCAP_ARG_SELECTOR:
1165             printf("selctor\n");
1166             break;
1167             case EXTCAP_ARG_STRING:
1168             printf ( "string\n" );
1169             break;
1170             case EXTCAP_ARG_PASSWORD:
1171             printf ( "PASSWORD\n" );
1172             break;
1173             case EXTCAP_ARG_MULTICHECK:
1174             printf ( "unknown\n" );
1175             break;
1176             case EXTCAP_ARG_UNKNOWN:
1177             printf ( "unknown\n" );
1178             break;
1179         }
1180
1181         if (arg_iter->range_start != NULL && arg_iter->range_end != NULL) {
1182             printf("\tRange: ");
1183             extcap_printf_complex(arg_iter->range_start);
1184             printf(" - ");
1185             extcap_printf_complex(arg_iter->range_end);
1186             printf("\n");
1187         }
1188
1189         for ( walker = g_list_first ( arg_iter->value_list ); walker; walker = walker->next )
1190         {
1191             v = (extcap_value *)walker->data;
1192             if (v->is_default)
1193             printf("*");
1194             printf("\tcall=\"%p\" display=\"%p\"\n", v->call, v->display);
1195             printf("\tcall=\"%s\" display=\"%s\"\n", v->call, v->display);
1196         }
1197
1198         arg_iter = arg_iter->next_arg;
1199     }
1200 }
1201 #endif
1202
1203 /*
1204  * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
1205  *
1206  * Local variables:
1207  * c-basic-offset: 4
1208  * tab-width: 8
1209  * indent-tabs-mode: nil
1210  * End:
1211  *
1212  * vi: set shiftwidth=4 tabstop=8 expandtab:
1213  * :indentSize=4:tabSize=8:noTabs=true:
1214  */