5 * Ethereal - Network traffic analyzer
6 * By Gerald Combs <gerald@ethereal.com>
7 * Copyright 1998 Gerald Combs
9 * Text-mode variant, by Gilbert Ramirez <gram@alumni.rice.edu>
10 * and Guy Harris <guy@alum.mit.edu>.
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version 2
15 * of the License, or (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
27 /* With MSVC and a libethereal.dll this file needs to import some variables
28 in a special way. Therefore _NEED_VAR_IMPORT_ is defined. */
29 #define _NEED_VAR_IMPORT_
59 #ifdef HAVE_SYS_STAT_H
60 # include <sys/stat.h>
63 #ifdef NEED_SNPRINTF_H
64 # include "snprintf.h"
67 #ifdef NEED_STRERROR_H
75 #include "svnversion.h"
78 #include <epan/epan.h>
79 #include <epan/filesystem.h>
82 #include <epan/timestamp.h>
83 #include <epan/packet.h>
85 #include "disabled_protos.h"
89 #include <epan/resolv.h>
91 #include "version_info.h"
93 #include "pcap-util.h"
95 #include <epan/conversation.h>
96 #include <epan/plugins.h>
98 #include "conditions.h"
99 #include "capture_stop_conditions.h"
100 #include "ringbuffer.h"
101 #include <epan/epan_dissect.h>
103 #include <epan/timestamp.h>
106 #include <wiretap/wtap-capture.h>
107 #include <wiretap/libpcap.h>
111 #include "capture-wpcap.h"
115 * This is the template for the decode as option; it is shared between the
116 * various functions that output the usage for this parameter.
118 static const gchar decode_as_arg_template[] = "<layer_type>==<selector>,<decode_as_protocol>";
120 static guint32 firstsec, firstusec;
121 static guint32 prevsec, prevusec;
122 static GString *comp_info_str, *runtime_info_str;
123 static gboolean quiet;
125 static gboolean print_packet_info; /* TRUE if we're to print packet information */
127 * The way the packet decode is to be written.
130 WRITE_TEXT, /* summary or detail text */
131 WRITE_XML /* PDML or PSML */
132 /* Add CSV and the like here */
134 static output_action_e output_action;
135 static gboolean do_dissection; /* TRUE if we have to dissect each packet */
136 static gboolean verbose;
137 static gboolean print_hex;
138 static gboolean line_buffered;
139 static guint32 cum_bytes = 0;
140 static print_format_e print_format;
143 typedef struct _loop_data {
144 gboolean go; /* TRUE as long as we're supposed to keep capturing */
146 gboolean from_pipe; /* TRUE if we are capturing data from a pipe */
150 gboolean output_to_pipe;
153 gboolean modified; /* TRUE if data in the pipe uses modified pcap headers */
154 gboolean byte_swapped; /* TRUE if data in the pipe is byte swapped */
155 unsigned int bytes_to_read, bytes_read; /* Used by pipe_dispatch */
157 STATE_EXPECT_REC_HDR, STATE_READ_REC_HDR,
158 STATE_EXPECT_DATA, STATE_READ_DATA
161 enum { PIPOK, PIPEOF, PIPERR, PIPNEXIST } pipe_err;
167 static int capture(int);
168 static void capture_pcap_cb(guchar *, const struct pcap_pkthdr *,
170 static void report_counts(void);
172 static BOOL WINAPI capture_cleanup(DWORD);
174 static void capture_cleanup(int);
176 static void report_counts_siginfo(int);
179 #endif /* HAVE_LIBPCAP */
181 static int load_cap_file(capture_file *, int);
182 static gboolean process_packet(capture_file *cf, wtap_dumper *pdh, long offset,
183 const struct wtap_pkthdr *whdr, union wtap_pseudo_header *pseudo_header,
184 const guchar *pd, int *err);
185 static void show_capture_file_io_error(const char *, int, gboolean);
186 static void show_print_file_io_error(int err);
187 static void write_preamble(capture_file *cf);
188 static void print_packet(capture_file *cf, epan_dissect_t *edt);
189 static void write_finale(void);
190 static char *cf_open_error_message(int err, gchar *err_info,
191 gboolean for_writing, int file_type);
194 static void adjust_header(loop_data *, struct pcap_hdr *, struct pcaprec_hdr *);
195 static int pipe_open_live(char *, struct pcap_hdr *, loop_data *, char *, int);
196 static int pipe_dispatch(int, loop_data *, struct pcap_hdr *, \
197 struct pcaprec_modified_hdr *, guchar *, char *, int);
201 static void open_failure_message(const char *filename, int err,
202 gboolean for_writing);
203 static void failure_message(const char *msg_format, va_list ap);
204 static void read_failure_message(const char *filename, int err);
209 int snaplen; /* Maximum captured packet length */
210 int promisc_mode; /* Capture in promiscuous mode */
211 int autostop_count; /* Maximum packet count */
212 gboolean has_autostop_duration; /* TRUE if maximum capture duration
214 gint32 autostop_duration; /* Maximum capture duration */
215 gboolean has_autostop_filesize; /* TRUE if maximum capture file size
217 gint32 autostop_filesize; /* Maximum capture file size */
218 gboolean ringbuffer_on; /* TRUE if ring buffer in use */
219 guint32 ringbuffer_num_files; /* Number of ring buffer files */
220 gboolean has_ring_duration; /* TRUE if ring duration specified */
221 gint32 ringbuffer_duration; /* Switch file after n seconds */
222 int linktype; /* Data link type to use, or -1 for
226 static capture_options capture_opts = {
227 WTAP_MAX_PACKET_SIZE, /* snapshot length - default is
228 infinite, in effect */
229 TRUE, /* promiscuous mode is the default */
230 0, /* max packet count - default is 0,
232 FALSE, /* maximum capture duration not
233 specified by default */
234 0, /* maximum capture duration */
235 FALSE, /* maximum capture file size not
236 specified by default */
237 0, /* maximum capture file size */
238 FALSE, /* ring buffer off by default */
239 RINGBUFFER_MIN_NUM_FILES, /* default number of ring buffer
241 FALSE, /* Switch ring file after some */
242 0, /* specified time is off by default */
243 -1 /* Default to not change link type */
246 static gboolean list_link_layer_types;
249 static gboolean infodelay; /* if TRUE, don't print capture info in SIGINFO handler */
250 static gboolean infoprint; /* if TRUE, print capture info after clearing infodelay */
252 #endif /* HAVE_LIBPCAP */
255 print_usage(gboolean print_ver)
262 fprintf(output, "This is GNU t" PACKAGE " " VERSION
266 "\n (C) 1998-2004 Gerald Combs <gerald@ethereal.com>"
269 comp_info_str->str, runtime_info_str->str);
274 fprintf(output, "\nt%s [ -vh ] [ -DlLnpqSVx ] [ -a <capture autostop condition> ] ...\n",
276 fprintf(output, "\t[ -b <number of ring buffer files>[:<duration>] ] [ -c <count> ]\n");
277 fprintf(output, "\t[ -d %s ] ...\n", decode_as_arg_template);
278 fprintf(output, "\t[ -f <capture filter> ] [ -F <output file type> ] [ -i <interface> ]\n");
279 fprintf(output, "\t[ -N <resolving> ] [ -o <preference setting> ] ... [ -r <infile> ]\n");
280 fprintf(output, "\t[ -R <read filter> ] [ -s <snaplen> ] [ -t <time stamp format> ]\n");
281 fprintf(output, "\t[ -T pdml|ps|text ] [ -w <savefile> ] [ -y <link type> ]\n");
282 fprintf(output, "\t[ -z <statistics string> ]\n");
284 fprintf(output, "\nt%s [ -vh ] [ -lnVx ]\n", PACKAGE);
285 fprintf(output, "\t[ -d %s ] ...\n", decode_as_arg_template);
286 fprintf(output, "\t[ -F <output file type> ] [ -N <resolving> ]\n");
287 fprintf(output, "\t[ -o <preference setting> ] ... [ -r <infile> ] [ -R <read filter> ]\n");
288 fprintf(output, "\t[ -t <time stamp format> ] [ -T pdml|ps|text ] [ -w <savefile> ]\n");
289 fprintf(output, "\t[ -z <statistics string> ]\n");
291 fprintf(output, "Valid file type arguments to the \"-F\" flag:\n");
292 for (i = 0; i < WTAP_NUM_FILE_TYPES; i++) {
293 if (wtap_dump_can_open(i))
294 fprintf(output, "\t%s - %s\n",
295 wtap_file_type_short_string(i), wtap_file_type_string(i));
297 fprintf(output, "\tdefault is libpcap\n");
302 get_natural_int(const char *string, const char *name)
307 number = strtol(string, &p, 10);
308 if (p == string || *p != '\0') {
309 fprintf(stderr, "tethereal: The specified %s \"%s\" is not a decimal number\n",
314 fprintf(stderr, "tethereal: The specified %s is a negative number\n",
318 if (number > INT_MAX) {
319 fprintf(stderr, "tethereal: The specified %s is too large (greater than %d)\n",
327 get_positive_int(const char *string, const char *name)
331 number = get_natural_int(string, name);
334 fprintf(stderr, "tethereal: The specified %s is zero\n",
343 * Given a string of the form "<autostop criterion>:<value>", as might appear
344 * as an argument to a "-a" option, parse it and set the criterion in
345 * question. Return an indication of whether it succeeded or failed
349 set_autostop_criterion(const char *autostoparg)
353 colonp = strchr(autostoparg, ':');
361 * Skip over any white space (there probably won't be any, but
362 * as we allow it in the preferences file, we might as well
369 * Put the colon back, so if our caller uses, in an
370 * error message, the string they passed us, the message
376 if (strcmp(autostoparg,"duration") == 0) {
377 capture_opts.has_autostop_duration = TRUE;
378 capture_opts.autostop_duration = get_positive_int(p,"autostop duration");
379 } else if (strcmp(autostoparg,"filesize") == 0) {
380 capture_opts.has_autostop_filesize = TRUE;
381 capture_opts.autostop_filesize = get_positive_int(p,"autostop filesize");
385 *colonp = ':'; /* put the colon back */
390 * Given a string of the form "<ring buffer file>:<duration>", as might appear
391 * as an argument to a "-b" option, parse it and set the arguments in
392 * question. Return an indication of whether it succeeded or failed
396 get_ring_arguments(const char *arg)
398 guchar *p = NULL, *colonp;
400 colonp = strchr(arg, ':');
402 if (colonp != NULL) {
407 capture_opts.ringbuffer_num_files =
408 get_natural_int(arg, "number of ring buffer files");
414 * Skip over any white space (there probably won't be any, but
415 * as we allow it in the preferences file, we might as well
422 * Put the colon back, so if our caller uses, in an
423 * error message, the string they passed us, the message
430 capture_opts.has_ring_duration = TRUE;
431 capture_opts.ringbuffer_duration = get_positive_int(p,
432 "ring buffer duration");
434 *colonp = ':'; /* put the colon back */
439 /* structure to keep track of what tap listeners have been registered.
441 typedef struct _ethereal_tap_list {
442 struct _ethereal_tap_list *next;
444 void (*func)(char *arg);
446 static ethereal_tap_list *tap_list=NULL;
449 register_ethereal_tap(char *cmd, void (*func)(char *arg))
451 ethereal_tap_list *newtl;
453 newtl=malloc(sizeof(ethereal_tap_list));
454 newtl->next=tap_list;
462 * For a dissector table, print on the stream described by output,
463 * its short name (which is what's used in the "-d" option) and its
467 display_dissector_table_names(char *table_name, char *ui_name, gpointer output)
469 fprintf((FILE *)output, "\t%s (%s)\n", table_name, ui_name);
473 * For a dissector handle, print on the stream described by output,
474 * the filter name (which is what's used in the "-d" option) and the full
475 * name for the protocol that corresponds to this handle.
478 display_dissector_names(gchar *table _U_, gpointer handle, gpointer output)
481 const gchar* proto_filter_name;
482 const gchar* proto_ui_name;
484 proto_id = dissector_handle_get_protocol_index((dissector_handle_t)handle);
486 if (proto_id != -1) {
487 proto_filter_name = proto_get_protocol_filter_name(proto_id);
488 proto_ui_name = proto_get_protocol_name(proto_id);
489 g_assert(proto_filter_name != NULL);
490 g_assert(proto_ui_name != NULL);
492 fprintf((FILE *)output, "\t%s (%s)\n",
499 * The protocol_name_search structure is used by find_protocol_name_func()
500 * to pass parameters and store results
502 struct protocol_name_search{
503 gchar *searched_name; /* Protocol filter name we are looking for */
504 dissector_handle_t matched_handle; /* Handle for a dissector whose protocol has the specified filter name */
505 guint nb_match; /* How many dissectors matched searched_name */
507 typedef struct protocol_name_search *protocol_name_search_t;
510 * This function parses all dissectors associated with a table to find the
511 * one whose protocol has the specified filter name. It is called
512 * as a reference function in a call to dissector_table_foreach_handle.
513 * The name we are looking for, as well as the results, are stored in the
514 * protocol_name_search struct pointed to by user_data.
515 * If called using dissector_table_foreach_handle, we actually parse the
516 * whole list of dissectors.
519 find_protocol_name_func(gchar *table _U_, gpointer handle, gpointer user_data)
523 const gchar *protocol_filter_name;
524 protocol_name_search_t search_info;
528 search_info = (protocol_name_search_t)user_data;
530 proto_id = dissector_handle_get_protocol_index((dissector_handle_t)handle);
531 if (proto_id != -1) {
532 protocol_filter_name = proto_get_protocol_filter_name(proto_id);
533 g_assert(protocol_filter_name != NULL);
534 if (strcmp(protocol_filter_name, search_info->searched_name) == 0) {
536 if (search_info->nb_match == 0) {
537 /* Record this handle only if this is the first match */
538 search_info->matched_handle = (dissector_handle_t)handle; /* Record the handle for this matching dissector */
540 search_info->nb_match++;
546 * Print all layer type names supported.
547 * We send the output to the stream described by the handle output.
551 fprint_all_layer_types(FILE *output)
554 dissector_all_tables_foreach_table(display_dissector_table_names, (gpointer)output);
558 * Print all protocol names supported for a specific layer type.
559 * table_name contains the layer type name in which the search is performed.
560 * We send the output to the stream described by the handle output.
564 fprint_all_protocols_for_layer_types(FILE *output, gchar *table_name)
567 dissector_table_foreach_handle(table_name,
568 display_dissector_names,
573 * The function below parses the command-line parameters for the decode as
574 * feature (a string pointer by cl_param).
575 * It checks the format of the command-line, searches for a matching table
576 * and dissector. If a table/dissector match is not found, we display a
577 * summary of the available tables/dissectors (on stderr) and return FALSE.
578 * If everything is fine, we get the "Decode as" preference activated,
579 * then we return TRUE.
582 add_decode_as(const gchar *cl_param)
586 gchar *decoded_param;
587 gchar *remaining_param;
589 gchar *dissector_str;
590 dissector_handle_t dissector_matching;
591 dissector_table_t table_matching;
592 ftenum_t dissector_table_selector_type;
593 struct protocol_name_search user_protocol_name;
595 /* The following code will allocate and copy the command-line options in a string pointed by decoded_param */
598 decoded_param = g_malloc( sizeof(gchar) * (strlen(cl_param) + 1) ); /* Allocate enough space to have a working copy of the command-line parameter */
599 g_assert(decoded_param);
600 strcpy(decoded_param, cl_param);
603 /* The lines below will parse this string (modifying it) to extract all
604 necessary information. Note that decoded_param is still needed since
605 strings are not copied - we just save pointers. */
607 /* This section extracts a layer type (table_name) from decoded_param */
608 table_name = decoded_param; /* Layer type string starts from beginning */
610 remaining_param = strchr(table_name, '=');
611 if (remaining_param == NULL) {
612 fprintf(stderr, "tethereal: Parameter \"%s\" doesn't follow the template \"%s\"\n", cl_param, decode_as_arg_template);
613 /* If the argument does not follow the template, carry on anyway to check
614 if the table name is at least correct. If remaining_param is NULL,
615 we'll exit anyway further down */
618 *remaining_param = '\0'; /* Terminate the layer type string (table_name) where '=' was detected */
621 /* Remove leading and trailing spaces from the table name */
622 while ( table_name[0] == ' ' )
624 while ( table_name[strlen(table_name) - 1] == ' ' )
625 table_name[strlen(table_name) - 1] = '\0'; /* Note: if empty string, while loop will eventually exit */
627 /* The following part searches a table matching with the layer type specified */
628 table_matching = NULL;
630 /* Look for the requested table */
631 if ( !(*(table_name)) ) { /* Is the table name empty, if so, don't even search for anything, display a message */
632 fprintf(stderr, "tethereal: No layer type specified\n"); /* Note, we don't exit here, but table_matching will remain NULL, so we exit below */
635 table_matching = find_dissector_table(table_name);
636 if (!table_matching) {
637 fprintf(stderr, "tethereal: Unknown layer type -- %s\n", table_name); /* Note, we don't exit here, but table_matching will remain NULL, so we exit below */
641 if (!table_matching) {
642 /* Display a list of supported layer types to help the user, if the
643 specified layer type was not found */
644 fprintf(stderr, "tethereal: Valid layer types are:\n");
645 fprint_all_layer_types(stderr);
647 if (remaining_param == NULL || !table_matching) {
648 /* Exit if the layer type was not found, or if no '=' separator was found
650 g_free(decoded_param);
654 if (*(remaining_param + 1) != '=') { /* Check for "==" and not only '=' */
655 fprintf(stderr, "tethereal: WARNING: -d requires \"==\" instead of \"=\". Option will be treated as \"%s==%s\"\n", table_name, remaining_param + 1);
658 remaining_param++; /* Move to the second '=' */
659 *remaining_param = '\0'; /* Remove the second '=' */
661 remaining_param++; /* Position after the layer type string */
663 /* This section extracts a selector value (selector_str) from decoded_param */
665 selector_str = remaining_param; /* Next part starts with the selector number */
667 remaining_param = strchr(selector_str, ',');
668 if (remaining_param == NULL) {
669 fprintf(stderr, "tethereal: Parameter \"%s\" doesn't follow the template \"%s\"\n", cl_param, decode_as_arg_template);
670 /* If the argument does not follow the template, carry on anyway to check
671 if the selector value is at least correct. If remaining_param is NULL,
672 we'll exit anyway further down */
675 *remaining_param = '\0'; /* Terminate the selector number string (selector_str) where ',' was detected */
678 dissector_table_selector_type = get_dissector_table_selector_type(table_name);
680 switch (dissector_table_selector_type) {
686 /* The selector for this table is an unsigned number. Parse it as such.
687 There's no need to remove leading and trailing spaces from the
688 selector number string, because sscanf will do that for us. */
689 if ( sscanf(selector_str, "%u", &selector) != 1 ) {
690 fprintf(stderr, "tethereal: Invalid selector number \"%s\"\n", selector_str);
691 g_free(decoded_param);
698 /* The selector for this table is a string. */
702 /* There are currently no dissector tables with any types other
703 than the ones listed above. */
704 g_assert_not_reached();
707 if (remaining_param == NULL) {
708 /* Exit if no ',' separator was found (see above) */
709 fprintf(stderr, "tethereal: Valid protocols for layer type \"%s\" are:\n", table_name);
710 fprint_all_protocols_for_layer_types(stderr, table_name);
711 g_free(decoded_param);
715 remaining_param++; /* Position after the selector number string */
717 /* This section extracts a protocol filter name (dissector_str) from decoded_param */
719 dissector_str = remaining_param; /* All the rest of the string is the dissector (decode as protocol) name */
721 /* Remove leading and trailing spaces from the dissector name */
722 while ( dissector_str[0] == ' ' )
724 while ( dissector_str[strlen(dissector_str) - 1] == ' ' )
725 dissector_str[strlen(dissector_str) - 1] = '\0'; /* Note: if empty string, while loop will eventually exit */
727 dissector_matching = NULL;
729 /* We now have a pointer to the handle for the requested table inside the variable table_matching */
730 if ( ! (*dissector_str) ) { /* Is the dissector name empty, if so, don't even search for a matching dissector and display all dissectors found for the selected table */
731 fprintf(stderr, "tethereal: No protocol name specified\n"); /* Note, we don't exit here, but dissector_matching will remain NULL, so we exit below */
734 user_protocol_name.nb_match = 0;
735 user_protocol_name.searched_name = dissector_str;
736 user_protocol_name.matched_handle = NULL;
738 dissector_table_foreach_handle(table_name, find_protocol_name_func, &user_protocol_name); /* Go and perform the search for this dissector in the this table's dissectors' names and shortnames */
740 if (user_protocol_name.nb_match != 0) {
741 dissector_matching = user_protocol_name.matched_handle;
742 if (user_protocol_name.nb_match > 1) {
743 fprintf(stderr, "tethereal: WARNING: Protocol \"%s\" matched %u dissectors, first one will be used\n", dissector_str, user_protocol_name.nb_match);
747 /* OK, check whether the problem is that there isn't any such
748 protocol, or that there is but it's not specified as a protocol
749 that's valid for that dissector table.
750 Note, we don't exit here, but dissector_matching will remain NULL,
752 if (proto_get_id_by_filter_name(dissector_str) == -1) {
753 /* No such protocol */
754 fprintf(stderr, "tethereal: Unknown protocol -- \"%s\"\n", dissector_str);
756 fprintf(stderr, "tethereal: Protocol \"%s\" isn't valid for layer type \"%s\"\n",
757 dissector_str, table_name);
762 if (!dissector_matching) {
763 fprintf(stderr, "tethereal: Valid protocols for layer type \"%s\" are:\n", table_name);
764 fprint_all_protocols_for_layer_types(stderr, table_name);
765 g_free(decoded_param);
769 /* This is the end of the code that parses the command-line options.
770 All information is now stored in the variables:
774 The above variables that are strings are still pointing to areas within
775 decoded_parm. decoded_parm thus still needs to be kept allocated in
776 until we stop needing these variables
777 decoded_param will be deallocated at each exit point of this function */
780 /* We now have a pointer to the handle for the requested dissector
781 (requested protocol) inside the variable dissector_matching */
782 switch (dissector_table_selector_type) {
788 /* The selector for this table is an unsigned number. */
789 dissector_change(table_name, selector, dissector_matching);
794 /* The selector for this table is a string. */
795 dissector_change_string(table_name, selector_str, dissector_matching);
799 /* There are currently no dissector tables with any types other
800 than the ones listed above. */
801 g_assert_not_reached();
803 g_free(decoded_param); /* "Decode As" rule has been succesfully added */
808 main(int argc, char *argv[])
812 gboolean arg_error = FALSE;
818 char *gpf_path, *pf_path;
819 char *gdp_path, *dp_path;
820 int gpf_open_errno, gpf_read_errno;
821 int pf_open_errno, pf_read_errno;
822 int gdp_open_errno, gdp_read_errno;
823 int dp_open_errno, dp_read_errno;
826 gboolean capture_filter_specified = FALSE;
827 GList *if_list, *if_entry;
831 gchar err_str[PCAP_ERRBUF_SIZE];
832 gchar *cant_get_if_list_errstr;
834 gboolean capture_option_specified = FALSE;
836 int out_file_type = WTAP_FILE_PCAP;
837 gchar *cf_name = NULL, *rfilter = NULL;
840 GList *lt_list, *lt_entry;
841 data_link_info_t *data_link_info;
843 #ifdef HAVE_PCAP_OPEN_DEAD
844 struct bpf_program fcode;
846 dfilter_t *rfcode = NULL;
849 ethereal_tap_list *tli;
851 set_timestamp_setting(TS_RELATIVE);
853 /* Register all dissectors; we must do this before checking for the
854 "-G" flag, as the "-G" flag dumps information registered by the
855 dissectors, and we must do it before we read the preferences, in
856 case any dissectors register preferences. */
857 epan_init(PLUGIN_DIR,register_all_protocols,register_all_protocol_handoffs,
858 failure_message,open_failure_message,read_failure_message);
860 /* Register all tap listeners; we do this before we parse the arguments,
861 as the "-z" argument can specify a registered tap. */
862 register_all_tap_listeners();
864 /* Now register the preferences for any non-dissector modules.
865 We must do that before we read the preferences as well. */
866 prefs_register_modules();
868 /* If invoked with the "-G" flag, we dump out information based on
869 the argument to the "-G" flag; if no argument is specified,
870 for backwards compatibility we dump out a glossary of display
873 We do this here to mirror what happens in the GTK+ version, although
874 it's not necessary here. */
875 if (argc >= 2 && strcmp(argv[1], "-G") == 0) {
877 proto_registrar_dump_fields();
879 if (strcmp(argv[2], "fields") == 0)
880 proto_registrar_dump_fields();
881 else if (strcmp(argv[2], "protocols") == 0)
882 proto_registrar_dump_protocols();
884 fprintf(stderr, "tethereal: Invalid \"%s\" option for -G flag\n",
892 /* Set the C-language locale to the native environment. */
893 setlocale(LC_ALL, "");
895 prefs = read_prefs(&gpf_open_errno, &gpf_read_errno, &gpf_path,
896 &pf_open_errno, &pf_read_errno, &pf_path);
897 if (gpf_path != NULL) {
898 if (gpf_open_errno != 0) {
899 fprintf(stderr, "Can't open global preferences file \"%s\": %s.\n",
900 pf_path, strerror(gpf_open_errno));
902 if (gpf_read_errno != 0) {
903 fprintf(stderr, "I/O error reading global preferences file \"%s\": %s.\n",
904 pf_path, strerror(gpf_read_errno));
907 if (pf_path != NULL) {
908 if (pf_open_errno != 0) {
909 fprintf(stderr, "Can't open your preferences file \"%s\": %s.\n", pf_path,
910 strerror(pf_open_errno));
912 if (pf_read_errno != 0) {
913 fprintf(stderr, "I/O error reading your preferences file \"%s\": %s.\n",
914 pf_path, strerror(pf_read_errno));
920 /* Set the name resolution code's flags from the preferences. */
921 g_resolv_flags = prefs->name_resolve;
923 /* Read the disabled protocols file. */
924 read_disabled_protos_list(&gdp_path, &gdp_open_errno, &gdp_read_errno,
925 &dp_path, &dp_open_errno, &dp_read_errno);
926 if (gdp_path != NULL) {
927 if (gdp_open_errno != 0) {
929 "Could not open global disabled protocols file\n\"%s\": %s.\n",
930 gdp_path, strerror(gdp_open_errno));
932 if (gdp_read_errno != 0) {
934 "I/O error reading global disabled protocols file\n\"%s\": %s.\n",
935 gdp_path, strerror(gdp_read_errno));
939 if (dp_path != NULL) {
940 if (dp_open_errno != 0) {
942 "Could not open your disabled protocols file\n\"%s\": %s.\n", dp_path,
943 strerror(dp_open_errno));
945 if (dp_read_errno != 0) {
947 "I/O error reading your disabled protocols file\n\"%s\": %s.\n", dp_path,
948 strerror(dp_read_errno));
954 /* Load Wpcap, if possible */
958 init_cap_file(&cfile);
960 /* Assemble the compile-time version information string */
961 comp_info_str = g_string_new("Compiled ");
962 get_compiled_version_info(comp_info_str);
964 /* Assemble the run-time version information string */
965 runtime_info_str = g_string_new("Running ");
966 get_runtime_version_info(runtime_info_str);
968 /* Print format defaults to this. */
969 print_format = PR_FMT_TEXT;
971 /* Now get our args */
972 while ((opt = getopt(argc, argv, "a:b:c:d:Df:F:hi:lLnN:o:pqr:R:s:St:T:vw:Vxy:z:")) != -1) {
974 case 'a': /* autostop criteria */
976 if (set_autostop_criterion(optarg) == FALSE) {
977 fprintf(stderr, "tethereal: Invalid or unknown -a flag \"%s\"\n", optarg);
981 capture_option_specified = TRUE;
985 case 'b': /* Ringbuffer option */
987 capture_opts.ringbuffer_on = TRUE;
988 if (get_ring_arguments(optarg) == FALSE) {
989 fprintf(stderr, "tethereal: Invalid or unknown -b arg \"%s\"\n", optarg);
993 capture_option_specified = TRUE;
997 case 'c': /* Capture xxx packets */
999 capture_opts.autostop_count =
1000 get_positive_int(optarg, "packet count");
1002 capture_option_specified = TRUE;
1006 case 'd': /* Decode as rule */
1007 if (!add_decode_as(optarg))
1010 case 'D': /* Print a list of capture devices */
1012 if_list = get_interface_list(&err, err_str);
1013 if (if_list == NULL) {
1016 case CANT_GET_INTERFACE_LIST:
1017 cant_get_if_list_errstr =
1018 cant_get_if_list_error_message(err_str);
1019 fprintf(stderr, "tethereal: %s\n", cant_get_if_list_errstr);
1020 g_free(cant_get_if_list_errstr);
1023 case NO_INTERFACES_FOUND:
1024 fprintf(stderr, "tethereal: There are no interfaces on which a capture can be done\n");
1029 i = 1; /* Interface id number */
1030 for (if_entry = g_list_first(if_list); if_entry != NULL;
1031 if_entry = g_list_next(if_entry)) {
1032 if_info = if_entry->data;
1033 printf("%d. %s", i++, if_info->name);
1034 if (if_info->description != NULL)
1035 printf(" (%s)", if_info->description);
1038 free_interface_list(if_list);
1041 capture_option_specified = TRUE;
1047 capture_filter_specified = TRUE;
1049 g_free(cfile.cfilter);
1050 cfile.cfilter = g_strdup(optarg);
1052 capture_option_specified = TRUE;
1057 out_file_type = wtap_short_string_to_file_type(optarg);
1058 if (out_file_type < 0) {
1059 fprintf(stderr, "tethereal: \"%s\" is not a valid capture file type\n",
1064 case 'h': /* Print help and exit */
1068 case 'i': /* Use interface xxx */
1071 * If the argument is a number, treat it as an index into the list
1072 * of adapters, as printed by "tethereal -D".
1074 * This should be OK on UNIX systems, as interfaces shouldn't have
1075 * names that begin with digits. It can be useful on Windows, where
1076 * more than one interface can have the same name.
1078 adapter_index = strtol(optarg, &p, 10);
1079 if (p != NULL && *p == '\0') {
1080 if (adapter_index < 0) {
1082 "tethereal: The specified adapter index is a negative number\n");
1085 if (adapter_index > INT_MAX) {
1087 "tethereal: The specified adapter index is too large (greater than %d)\n",
1091 if (adapter_index == 0) {
1092 fprintf(stderr, "tethereal: there is no interface with that adapter index\n");
1095 if_list = get_interface_list(&err, err_str);
1096 if (if_list == NULL) {
1099 case CANT_GET_INTERFACE_LIST:
1100 cant_get_if_list_errstr =
1101 cant_get_if_list_error_message(err_str);
1102 fprintf(stderr, "tethereal: %s\n", cant_get_if_list_errstr);
1103 g_free(cant_get_if_list_errstr);
1106 case NO_INTERFACES_FOUND:
1107 fprintf(stderr, "tethereal: There are no interfaces on which a capture can be done\n");
1112 if_info = g_list_nth_data(if_list, adapter_index - 1);
1113 if (if_info == NULL) {
1114 fprintf(stderr, "tethereal: there is no interface with that adapter index\n");
1117 cfile.iface = g_strdup(if_info->name);
1118 free_interface_list(if_list);
1120 cfile.iface = g_strdup(optarg);
1122 capture_option_specified = TRUE;
1126 case 'l': /* "Line-buffer" standard output */
1127 /* This isn't line-buffering, strictly speaking, it's just
1128 flushing the standard output after the information for
1129 each packet is printed; however, that should be good
1130 enough for all the purposes to which "-l" is put (and
1131 is probably actually better for "-V", as it does fewer
1134 See the comment in "process_packet()" for an explanation of
1135 why we do that, and why we don't just use "setvbuf()" to
1136 make the standard output line-buffered (short version: in
1137 Windows, "line-buffered" is the same as "fully-buffered",
1138 and the output buffer is only flushed when it fills up). */
1139 line_buffered = TRUE;
1141 case 'L': /* Print list of link-layer types and exit */
1143 list_link_layer_types = TRUE;
1146 capture_option_specified = TRUE;
1150 case 'n': /* No name resolution */
1151 g_resolv_flags = RESOLV_NONE;
1153 case 'N': /* Select what types of addresses/port #s to resolve */
1154 if (g_resolv_flags == RESOLV_ALL)
1155 g_resolv_flags = RESOLV_NONE;
1156 badopt = string_to_name_resolve(optarg, &g_resolv_flags);
1157 if (badopt != '\0') {
1158 fprintf(stderr, "tethereal: -N specifies unknown resolving option '%c'; valid options are 'm', 'n', and 't'\n",
1163 case 'o': /* Override preference from command line */
1164 switch (prefs_set_pref(optarg)) {
1166 case PREFS_SET_SYNTAX_ERR:
1167 fprintf(stderr, "tethereal: Invalid -o flag \"%s\"\n", optarg);
1171 case PREFS_SET_NO_SUCH_PREF:
1172 case PREFS_SET_OBSOLETE:
1173 fprintf(stderr, "tethereal: -o flag \"%s\" specifies unknown preference\n",
1179 case 'p': /* Don't capture in promiscuous mode */
1181 capture_opts.promisc_mode = FALSE;
1183 capture_option_specified = TRUE;
1187 case 'q': /* Quiet */
1190 case 'r': /* Read capture file xxx */
1191 cf_name = g_strdup(optarg);
1193 case 'R': /* Read file filter */
1196 case 's': /* Set the snapshot (capture) length */
1198 capture_opts.snaplen = get_positive_int(optarg, "snapshot length");
1200 capture_option_specified = TRUE;
1204 case 'S': /* show packets in real time */
1205 print_packet_info = TRUE;
1207 case 't': /* Time stamp type */
1208 if (strcmp(optarg, "r") == 0)
1209 set_timestamp_setting(TS_RELATIVE);
1210 else if (strcmp(optarg, "a") == 0)
1211 set_timestamp_setting(TS_ABSOLUTE);
1212 else if (strcmp(optarg, "ad") == 0)
1213 set_timestamp_setting(TS_ABSOLUTE_WITH_DATE);
1214 else if (strcmp(optarg, "d") == 0)
1215 set_timestamp_setting(TS_DELTA);
1217 fprintf(stderr, "tethereal: Invalid time stamp type \"%s\"\n",
1219 fprintf(stderr, "It must be \"r\" for relative, \"a\" for absolute,\n");
1220 fprintf(stderr, "\"ad\" for absolute with date, or \"d\" for delta.\n");
1224 case 'T': /* printing Type */
1225 if (strcmp(optarg, "text") == 0) {
1226 output_action = WRITE_TEXT;
1227 print_format = PR_FMT_TEXT;
1228 } else if (strcmp(optarg, "ps") == 0) {
1229 output_action = WRITE_TEXT;
1230 print_format = PR_FMT_PS;
1232 } else if (strcmp(optarg, "pdml") == 0) {
1233 output_action = WRITE_XML;
1235 } else if (strcmp(optarg, "psml") == 0) {
1236 output_action = WRITE_XML;
1239 fprintf(stderr, "tethereal: Invalid -T parameter.\n");
1240 fprintf(stderr, "It must be \"ps\", \"text\", \"pdml\", or \"psml\".\n");
1244 case 'v': /* Show version and exit */
1245 printf("t" PACKAGE " " VERSION
1250 comp_info_str->str, runtime_info_str->str);
1253 case 'w': /* Write to capture file xxx */
1254 cfile.save_file = g_strdup(optarg);
1256 case 'V': /* Verbose */
1259 case 'x': /* Print packet data in hex (and ASCII) */
1262 case 'y': /* Set the pcap data link type */
1264 #ifdef HAVE_PCAP_DATALINK_NAME_TO_VAL
1265 capture_opts.linktype = pcap_datalink_name_to_val(optarg);
1266 if (capture_opts.linktype == -1) {
1267 fprintf(stderr, "tethereal: The specified data link type \"%s\" is not valid\n",
1271 #else /* HAVE_PCAP_DATALINK_NAME_TO_VAL */
1272 /* XXX - just treat it as a number */
1273 capture_opts.linktype = get_natural_int(optarg, "data link type");
1274 #endif /* HAVE_PCAP_DATALINK_NAME_TO_VAL */
1276 capture_option_specified = TRUE;
1281 for(tli=tap_list;tli;tli=tli->next){
1282 if(!strncmp(tli->cmd,optarg,strlen(tli->cmd))){
1283 (*tli->func)(optarg);
1288 fprintf(stderr,"tethereal: invalid -z argument.\n");
1289 fprintf(stderr," -z argument must be one of :\n");
1290 for(tli=tap_list;tli;tli=tli->next){
1291 fprintf(stderr," %s\n",tli->cmd);
1297 case '?': /* Bad flag - print usage message */
1303 /* If no capture filter or read filter has been specified, and there are
1304 still command-line arguments, treat them as the tokens of a capture
1305 filter (if no "-r" flag was specified) or a read filter (if a "-r"
1306 flag was specified. */
1307 if (optind < argc) {
1308 if (cf_name != NULL) {
1309 if (rfilter != NULL) {
1311 "tethereal: Read filters were specified both with \"-R\" and with additional command-line arguments\n");
1314 rfilter = get_args_as_string(argc, argv, optind);
1317 if (capture_filter_specified) {
1319 "tethereal: Capture filters were specified both with \"-f\" and with additional command-line arguments\n");
1322 cfile.cfilter = get_args_as_string(argc, argv, optind);
1324 capture_option_specified = TRUE;
1329 /* See if we're writing a capture file and the file is a pipe */
1331 ld.output_to_pipe = FALSE;
1333 if (cfile.save_file != NULL) {
1334 /* We're writing to a capture file. */
1335 if (strcmp(cfile.save_file, "-") == 0) {
1336 /* Write to the standard output. */
1337 g_free(cfile.save_file);
1338 cfile.save_file = g_strdup("");
1340 /* XXX - should we check whether it's a pipe? It's arguably
1341 silly to do "-w - >output_file" rather than "-w output_file",
1342 but by not checking we might be violating the Principle Of
1343 Least Astonishment. */
1344 ld.output_to_pipe = TRUE;
1349 err = test_for_fifo(cfile.save_file);
1352 case ENOENT: /* it doesn't exist, so we'll be creating it,
1353 and it won't be a FIFO */
1354 case 0: /* found it, but it's not a FIFO */
1357 case ESPIPE: /* it is a FIFO */
1358 ld.output_to_pipe = TRUE;
1361 default: /* couldn't stat it */
1363 "tethereal: Error testing whether capture file is a pipe: %s\n",
1370 /* We're not writing to a file, so we should print packet information
1371 unless "-q" was specified. */
1373 print_packet_info = TRUE;
1376 #ifndef HAVE_LIBPCAP
1377 if (capture_option_specified)
1378 fprintf(stderr, "This version of Tethereal was not built with support for capturing packets.\n");
1386 if (output_action != WRITE_TEXT) {
1387 fprintf(stderr, "tethereal: Raw packet hex data can only be printed as text or PostScript\n");
1393 if (list_link_layer_types) {
1394 /* We're supposed to list the link-layer types for an interface;
1395 did the user also specify a capture file to be read? */
1397 /* Yes - that's bogus. */
1398 fprintf(stderr, "tethereal: You cannot specify -L and a capture file to be read.\n");
1401 /* No - did they specify a ring buffer option? */
1402 if (capture_opts.ringbuffer_on) {
1403 fprintf(stderr, "tethereal: Ring buffer requested, but a capture is not being done.\n");
1407 /* If they didn't specify a "-w" flag, but specified a maximum capture
1408 file size, tell them that this doesn't work, and exit. */
1409 if (capture_opts.has_autostop_filesize && cfile.save_file == NULL) {
1410 fprintf(stderr, "tethereal: Maximum capture file size specified, but "
1411 "capture isn't being saved to a file.\n");
1415 if (capture_opts.ringbuffer_on) {
1416 /* Ring buffer works only under certain conditions:
1417 a) ring buffer does not work if you're not saving the capture to
1419 b) ring buffer only works if you're saving in libpcap format;
1420 c) it makes no sense to enable the ring buffer if the maximum
1421 file size is set to "infinite";
1422 d) file must not be a pipe. */
1423 if (cfile.save_file == NULL) {
1424 fprintf(stderr, "tethereal: Ring buffer requested, but "
1425 "capture isn't being saved to a file.\n");
1428 if (out_file_type != WTAP_FILE_PCAP) {
1429 fprintf(stderr, "tethereal: Ring buffer requested, but "
1430 "capture isn't being saved in libpcap format.\n");
1433 if (!capture_opts.has_autostop_filesize) {
1434 fprintf(stderr, "tethereal: Ring buffer requested, but "
1435 "no maximum capture file size was specified.\n");
1438 if (ld.output_to_pipe) {
1439 fprintf(stderr, "tethereal: Ring buffer requested, but "
1440 "capture file is a pipe.\n");
1448 /* Start windows sockets */
1449 WSAStartup( MAKEWORD( 1, 1 ), &wsaData );
1452 /* Notify all registered modules that have had any of their preferences
1453 changed either from one of the preferences file or from the command
1454 line that their preferences have changed. */
1457 /* disabled protocols as per configuration file */
1458 if (gdp_path == NULL && dp_path == NULL) {
1459 set_disabled_protos_list();
1462 /* Build the column format array */
1463 col_setup(&cfile.cinfo, prefs->num_cols);
1464 for (i = 0; i < cfile.cinfo.num_cols; i++) {
1465 cfile.cinfo.col_fmt[i] = get_column_format(i);
1466 cfile.cinfo.col_title[i] = g_strdup(get_column_title(i));
1467 cfile.cinfo.fmt_matx[i] = (gboolean *) g_malloc0(sizeof(gboolean) *
1469 get_column_format_matches(cfile.cinfo.fmt_matx[i], cfile.cinfo.col_fmt[i]);
1470 cfile.cinfo.col_data[i] = NULL;
1471 if (cfile.cinfo.col_fmt[i] == COL_INFO)
1472 cfile.cinfo.col_buf[i] = (gchar *) g_malloc(sizeof(gchar) * COL_MAX_INFO_LEN);
1474 cfile.cinfo.col_buf[i] = (gchar *) g_malloc(sizeof(gchar) * COL_MAX_LEN);
1475 cfile.cinfo.col_fence[i] = 0;
1476 cfile.cinfo.col_expr[i] = (gchar *) g_malloc(sizeof(gchar) * COL_MAX_LEN);
1477 cfile.cinfo.col_expr_val[i] = (gchar *) g_malloc(sizeof(gchar) * COL_MAX_LEN);
1480 for (i = 0; i < cfile.cinfo.num_cols; i++) {
1483 for (j = 0; j < NUM_COL_FMTS; j++) {
1484 if (!cfile.cinfo.fmt_matx[i][j])
1487 if (cfile.cinfo.col_first[j] == -1)
1488 cfile.cinfo.col_first[j] = i;
1489 cfile.cinfo.col_last[j] = i;
1494 if (capture_opts.snaplen < 1)
1495 capture_opts.snaplen = WTAP_MAX_PACKET_SIZE;
1496 else if (capture_opts.snaplen < MIN_PACKET_SIZE)
1497 capture_opts.snaplen = MIN_PACKET_SIZE;
1499 /* Check the value range of the ringbuffer_num_files parameter */
1500 if (capture_opts.ringbuffer_num_files > RINGBUFFER_MAX_NUM_FILES)
1501 capture_opts.ringbuffer_num_files = RINGBUFFER_MAX_NUM_FILES;
1502 #if RINGBUFFER_MIN_NUM_FILES > 0
1503 else if (capture_opts.ringbuffer_num_files < RINGBUFFER_MIN_NUM_FILES)
1504 capture_opts.ringbuffer_num_files = RINGBUFFER_MIN_NUM_FILES;
1508 if (rfilter != NULL) {
1509 if (!dfilter_compile(rfilter, &rfcode)) {
1510 fprintf(stderr, "tethereal: %s\n", dfilter_error_msg);
1512 #ifdef HAVE_PCAP_OPEN_DEAD
1516 p = pcap_open_dead(DLT_EN10MB, MIN_PACKET_SIZE);
1518 if (pcap_compile(p, &fcode, rfilter, 0, 0) != -1) {
1520 " Note: That display filter code looks like a valid capture filter;\n"
1521 " maybe you mixed them up?\n");
1530 cfile.rfcode = rfcode;
1532 /* We have to dissect each packet if:
1534 we're printing information about each packet;
1536 we're using a read filter on the packets;
1538 we're using any taps. */
1539 do_dissection = print_packet_info || rfcode || have_tap_listeners();
1543 * We're reading a capture file.
1548 * Immediately relinquish any set-UID or set-GID privileges we have;
1549 * we must not be allowed to read any capture files the user running
1550 * Tethereal can't open.
1556 err = cf_open(cf_name, FALSE, &cfile);
1561 err = load_cap_file(&cfile, out_file_type);
1568 /* No capture file specified, so we're supposed to do a live capture
1569 (or get a list of link-layer types for a live capture device);
1570 do we have support for live captures? */
1575 fprintf(stderr, "tethereal: Could not load wpcap.dll.\n");
1580 /* Yes; did the user specify an interface to use? */
1581 if (cfile.iface == NULL) {
1582 /* No - is a default specified in the preferences file? */
1583 if (prefs->capture_device != NULL) {
1585 if_text = strrchr(prefs->capture_device, ' ');
1586 if (if_text == NULL) {
1587 cfile.iface = g_strdup(prefs->capture_device);
1589 cfile.iface = g_strdup(if_text + 1); /* Skip over space */
1592 /* No - pick the first one from the list of interfaces. */
1593 if_list = get_interface_list(&err, err_str);
1594 if (if_list == NULL) {
1597 case CANT_GET_INTERFACE_LIST:
1598 cant_get_if_list_errstr =
1599 cant_get_if_list_error_message(err_str);
1600 fprintf(stderr, "tethereal: %s\n", cant_get_if_list_errstr);
1601 g_free(cant_get_if_list_errstr);
1604 case NO_INTERFACES_FOUND:
1605 fprintf(stderr, "tethereal: There are no interfaces on which a capture can be done\n");
1610 if_info = if_list->data; /* first interface */
1611 cfile.iface = g_strdup(if_info->name);
1612 free_interface_list(if_list);
1616 if (list_link_layer_types) {
1617 /* We were asked to list the link-layer types for an interface.
1618 Get the list of link-layer types for the capture device. */
1619 lt_list = get_pcap_linktype_list(cfile.iface, err_str);
1620 if (lt_list == NULL) {
1621 if (err_str[0] != '\0') {
1622 fprintf(stderr, "tethereal: The list of data link types for the capture device could not be obtained (%s).\n"
1623 "Please check to make sure you have sufficient permissions, and that\n"
1624 "you have the proper interface or pipe specified.\n", err_str);
1626 fprintf(stderr, "tethereal: The capture device has no data link types.\n");
1629 fprintf(stderr, "Data link types (use option -y to set):\n");
1630 for (lt_entry = lt_list; lt_entry != NULL;
1631 lt_entry = g_list_next(lt_entry)) {
1632 data_link_info = lt_entry->data;
1633 fprintf(stderr, " %s", data_link_info->name);
1634 if (data_link_info->description != NULL)
1635 fprintf(stderr, " (%s)", data_link_info->description);
1637 fprintf(stderr, " (not supported)");
1640 free_pcap_linktype_list(lt_list);
1644 capture(out_file_type);
1646 if (capture_opts.ringbuffer_on) {
1650 /* No - complain. */
1651 fprintf(stderr, "This version of Tethereal was not built with support for capturing packets.\n");
1656 draw_tap_listeners(TRUE);
1663 /* Do the low-level work of a capture.
1664 Returns TRUE if it succeeds, FALSE otherwise. */
1666 static condition *volatile cnd_ring_timeout = NULL; /* this must be visible in process_packet */
1669 capture(int out_file_type)
1673 gchar open_err_str[PCAP_ERRBUF_SIZE];
1674 gchar lookup_net_err_str[PCAP_ERRBUF_SIZE];
1675 bpf_u_int32 netnum, netmask;
1676 struct bpf_program fcode;
1677 const char *set_linktype_err_str;
1679 int volatile volatile_err = 0;
1680 int volatile inpkts = 0;
1682 char errmsg[1024+1];
1683 condition *volatile cnd_stop_capturesize = NULL;
1684 condition *volatile cnd_stop_timeout = NULL;
1686 void (*oldhandler)(int);
1687 static const char ppamsg[] = "can't find PPA for ";
1689 volatile int pipe_fd = -1;
1690 struct pcap_hdr hdr;
1691 struct pcaprec_modified_hdr rechdr;
1692 guchar pcap_data[WTAP_MAX_PACKET_SIZE];
1694 struct pcap_stat stats;
1697 dfilter_t *rfcode = NULL;
1699 /* Initialize all data structures used for dissection. */
1702 ld.linktype = WTAP_ENCAP_UNKNOWN;
1705 /* Open the network interface to capture from it.
1706 Some versions of libpcap may put warnings into the error buffer
1707 if they succeed; to tell if that's happened, we have to clear
1708 the error buffer, and check if it's still a null string. */
1709 open_err_str[0] = '\0';
1710 ld.pch = pcap_open_live(cfile.iface, capture_opts.snaplen,
1711 capture_opts.promisc_mode, 1000, open_err_str);
1713 if (ld.pch != NULL) {
1714 /* setting the data link type only works on real interfaces */
1715 if (capture_opts.linktype != -1) {
1716 set_linktype_err_str = set_pcap_linktype(ld.pch, cfile.iface,
1717 capture_opts.linktype);
1718 if (set_linktype_err_str != NULL) {
1719 snprintf(errmsg, sizeof errmsg, "Unable to set data link type (%s).",
1720 set_linktype_err_str);
1725 /* We couldn't open "cfile.iface" as a network device. */
1727 /* On Windows, we don't support capturing on pipes, so we give up. */
1729 /* On Win32 OSes, the capture devices are probably available to all
1730 users; don't warn about permissions problems.
1732 Do, however, warn that WAN devices aren't supported. */
1733 snprintf(errmsg, sizeof errmsg,
1734 "The capture session could not be initiated (%s).\n"
1735 "Please check that you have the proper interface specified.\n"
1737 "Note that the WinPcap 2.x version of the driver Ethereal uses for packet\n"
1738 "capture on Windows doesn't support capturing on PPP/WAN interfaces in\n"
1739 "Windows NT/2000/XP/2003 Server, and that the WinPcap 3.0 and later versions\n"
1740 "don't support capturing on PPP/WAN interfaces at all.\n",
1744 /* try to open cfile.iface as a pipe */
1745 pipe_fd = pipe_open_live(cfile.iface, &hdr, &ld, errmsg, sizeof errmsg);
1747 if (pipe_fd == -1) {
1749 if (ld.pipe_err == PIPNEXIST) {
1750 /* Pipe doesn't exist, so output message for interface */
1752 /* If we got a "can't find PPA for XXX" message, warn the user (who
1753 is running Tethereal on HP-UX) that they don't have a version
1754 of libpcap that properly handles HP-UX (libpcap 0.6.x and later
1755 versions, which properly handle HP-UX, say "can't find /dev/dlpi
1756 PPA for XXX" rather than "can't find PPA for XXX"). */
1757 if (strncmp(open_err_str, ppamsg, sizeof ppamsg - 1) == 0)
1760 "You are running Tethereal with a version of the libpcap library\n"
1761 "that doesn't handle HP-UX network devices well; this means that\n"
1762 "Tethereal may not be able to capture packets.\n"
1764 "To fix this, you should install libpcap 0.6.2, or a later version\n"
1765 "of libpcap, rather than libpcap 0.4 or 0.5.x. It is available in\n"
1766 "packaged binary form from the Software Porting And Archive Centre\n"
1767 "for HP-UX; the Centre is at http://hpux.connect.org.uk/ - the page\n"
1768 "at the URL lists a number of mirror sites.";
1771 snprintf(errmsg, sizeof errmsg,
1772 "The capture session could not be initiated (%s).\n"
1773 "Please check to make sure you have sufficient permissions, and that\n"
1774 "you have the proper interface or pipe specified.%s", open_err_str,
1778 * Else pipe (or file) does exist and pipe_open_live() has
1783 /* pipe_open_live() succeeded; don't want
1784 error message from pcap_open_live() */
1785 open_err_str[0] = '\0';
1791 * We've opened the capture device, so, if we're set-UID or set-GID,
1792 * relinquish those privileges.
1794 * XXX - if we have saved set-user-ID support, we should give up those
1795 * privileges immediately, and then reclaim them long enough to get
1796 * a list of network interfaces and to open one, and then give them
1797 * up again, so that stuff we do while processing the argument list,
1798 * reading the user's preferences, etc. is done as the real user and
1799 * group, not the effective user and group.
1805 if (cfile.cfilter && !ld.from_pipe) {
1806 /* A capture filter was specified; set it up. */
1807 if (pcap_lookupnet(cfile.iface, &netnum, &netmask, lookup_net_err_str) < 0) {
1809 * Well, we can't get the netmask for this interface; it's used
1810 * only for filters that check for broadcast IP addresses, so
1811 * we just warn the user, and punt and use 0.
1814 "Warning: Couldn't obtain netmask info (%s).\n", lookup_net_err_str);
1817 if (pcap_compile(ld.pch, &fcode, cfile.cfilter, 1, netmask) < 0) {
1818 if (dfilter_compile(cfile.cfilter, &rfcode)) {
1819 snprintf(errmsg, sizeof errmsg,
1820 "Unable to parse capture filter string (%s).\n"
1821 " Interestingly enough, this looks like a valid display filter\n"
1822 " Are you sure you didn't mix them up?",
1823 pcap_geterr(ld.pch));
1825 snprintf(errmsg, sizeof errmsg,
1826 "Unable to parse capture filter string (%s).",
1827 pcap_geterr(ld.pch));
1831 if (pcap_setfilter(ld.pch, &fcode) < 0) {
1832 snprintf(errmsg, sizeof errmsg, "Can't install filter (%s).",
1833 pcap_geterr(ld.pch));
1838 /* Set up to write to the capture file. */
1841 pcap_encap = hdr.network;
1842 file_snaplen = hdr.snaplen;
1846 pcap_encap = get_pcap_linktype(ld.pch, cfile.iface);
1847 file_snaplen = pcap_snapshot(ld.pch);
1849 ld.linktype = wtap_pcap_encap_to_wtap_encap(pcap_encap);
1850 if (cfile.save_file != NULL) {
1851 /* Set up to write to the capture file. */
1852 if (ld.linktype == WTAP_ENCAP_UNKNOWN) {
1853 strcpy(errmsg, "The network you're capturing from is of a type"
1854 " that Tethereal doesn't support.");
1857 if (capture_opts.ringbuffer_on) {
1858 cfile.save_file_fd = ringbuf_init(cfile.save_file,
1859 capture_opts.ringbuffer_num_files);
1860 if (cfile.save_file_fd != -1) {
1861 ld.pdh = ringbuf_init_wtap_dump_fdopen(out_file_type, ld.linktype,
1862 pcap_snapshot(ld.pch), &err);
1864 err = errno; /* "ringbuf_init()" failed */
1868 ld.pdh = wtap_dump_open(cfile.save_file, out_file_type,
1869 ld.linktype, pcap_snapshot(ld.pch), &err);
1872 if (ld.pdh == NULL) {
1873 snprintf(errmsg, sizeof errmsg,
1874 cf_open_error_message(err, NULL, TRUE, out_file_type),
1875 *cfile.save_file == '\0' ? "stdout" : cfile.save_file);
1880 /* Does "open_err_str" contain a non-empty string? If so, "pcap_open_live()"
1881 returned a warning; print it, but keep capturing. */
1882 if (open_err_str[0] != '\0')
1883 fprintf(stderr, "tethereal: WARNING: %s.\n", open_err_str);
1886 /* Catch a CTRL+C event and, if we get it, clean up and exit. */
1887 SetConsoleCtrlHandler(capture_cleanup, TRUE);
1889 /* Catch SIGINT and SIGTERM and, if we get either of them, clean up
1891 XXX - deal with signal semantics on various UNIX platforms. Or just
1892 use "sigaction()" and be done with it? */
1893 signal(SIGTERM, capture_cleanup);
1894 signal(SIGINT, capture_cleanup);
1895 if ((oldhandler = signal(SIGHUP, capture_cleanup)) != SIG_DFL)
1896 signal(SIGHUP, oldhandler);
1899 /* Catch SIGINFO and, if we get it and we're capturing to a file in
1900 quiet mode, report the number of packets we've captured. */
1901 signal(SIGINFO, report_counts_siginfo);
1902 #endif /* SIGINFO */
1905 /* Let the user know what interface was chosen. */
1906 fprintf(stderr, "Capturing on %s\n", cfile.iface);
1908 /* initialize capture stop conditions */
1909 init_capture_stop_conditions();
1910 /* create stop conditions */
1911 if (capture_opts.has_autostop_filesize)
1912 cnd_stop_capturesize = cnd_new((const char*)CND_CLASS_CAPTURESIZE,
1913 (long)capture_opts.autostop_filesize * 1000);
1914 if (capture_opts.has_autostop_duration)
1915 cnd_stop_timeout = cnd_new((const char*)CND_CLASS_TIMEOUT,
1916 (gint32)capture_opts.autostop_duration);
1918 if (capture_opts.ringbuffer_on && capture_opts.has_ring_duration)
1919 cnd_ring_timeout = cnd_new(CND_CLASS_TIMEOUT,
1920 capture_opts.ringbuffer_duration);
1922 if (!setjmp(ld.stopenv)) {
1924 ld.packet_count = 0;
1928 /* We need to be careful with automatic variables defined in the
1929 outer scope which are changed inside the loop. Most compilers
1930 don't try to roll them back to their original values after the
1931 longjmp which causes the loop to finish, but all that the
1932 standards say is that their values are indeterminate. If we
1933 don't want them to be rolled back, we should define them with the
1934 volatile attribute (paraphrasing W. Richard Stevens, Advanced
1935 Programming in the UNIX Environment, p. 178).
1937 The "err" variable causes a particular problem. If we give it
1938 the volatile attribute, then when we pass a reference to it (as
1939 in "&err") to a function, GCC warns: "passing arg <n> of
1940 <function> discards qualifiers from pointer target type".
1941 Therefore within the loop and just beyond we don't use "err".
1942 Within the loop we define "loop_err", and assign its value to
1943 "volatile_err", which is in the outer scope and is checked when
1946 We also define "packet_count_prev" here to keep things tidy,
1947 since it's used only inside the loop. If it were defined in the
1948 outer scope, GCC would give a warning (unnecessary in this case)
1949 that it might be clobbered, and we'd need to give it the volatile
1950 attribute to suppress the warning. */
1953 int packet_count_prev = 0;
1955 if (cnd_stop_capturesize == NULL && cnd_stop_timeout == NULL) {
1956 /* We're not stopping at a particular capture file size, and we're
1957 not stopping after some particular amount of time has expired,
1958 so either we have no stop condition or the only stop condition
1959 is a maximum packet count.
1961 If there's no maximum packet count, pass it -1, meaning "until
1962 you run out of packets in the bufferful you read". Otherwise,
1963 pass it the number of packets we have left to capture.
1965 We don't call "pcap_loop()" as, if we're saving to a file that's
1966 a FIFO, we want to flush the FIFO after we're done processing
1967 this libpcap bufferful of packets, so that the program
1968 reading the FIFO sees the packets immediately and doesn't get
1969 any partial packet, forcing it to block in the middle of reading
1971 if (capture_opts.autostop_count == 0)
1974 if (ld.packet_count >= capture_opts.autostop_count) {
1975 /* XXX do we need this test here? */
1976 /* It appears there's nothing more to capture. */
1979 pcap_cnt = capture_opts.autostop_count - ld.packet_count;
1982 /* We need to check the capture file size or the timeout after
1988 inpkts = pipe_dispatch(pipe_fd, &ld, &hdr, &rechdr, pcap_data,
1989 errmsg, sizeof errmsg);
1992 inpkts = pcap_dispatch(ld.pch, pcap_cnt, capture_pcap_cb, (guchar *) &ld);
1994 /* Error from "pcap_dispatch()", or error or "no more packets" from
1995 "pipe_dispatch(). */
1997 } else if (cnd_stop_timeout != NULL && cnd_eval(cnd_stop_timeout)) {
1998 /* The specified capture time has elapsed; stop the capture. */
2000 } else if (inpkts > 0) {
2001 if (capture_opts.autostop_count != 0 &&
2002 ld.packet_count >= capture_opts.autostop_count) {
2003 /* The specified number of packets have been captured and have
2004 passed both any capture filter in effect and any read filter
2007 } else if (cnd_stop_capturesize != NULL &&
2008 cnd_eval(cnd_stop_capturesize,
2009 (guint32)wtap_get_bytes_dumped(ld.pdh))) {
2010 /* We're saving the capture to a file, and the capture file reached
2011 its maximum size. */
2012 if (capture_opts.ringbuffer_on) {
2013 /* Switch to the next ringbuffer file */
2014 if (ringbuf_switch_file(&cfile, &ld.pdh, &loop_err)) {
2015 /* File switch succeeded: reset the condition */
2016 cnd_reset(cnd_stop_capturesize);
2017 if (cnd_ring_timeout) {
2018 cnd_reset(cnd_ring_timeout);
2021 /* File switch failed: stop here */
2022 volatile_err = loop_err;
2026 /* No ringbuffer - just stop. */
2030 if (ld.output_to_pipe) {
2031 if (ld.packet_count > packet_count_prev) {
2032 if (fflush(wtap_dump_file(ld.pdh))) {
2033 volatile_err = errno;
2036 packet_count_prev = ld.packet_count;
2040 } /* while (ld.go) */
2042 /* delete stop conditions */
2043 if (cnd_stop_capturesize != NULL)
2044 cnd_delete(cnd_stop_capturesize);
2045 if (cnd_stop_timeout != NULL)
2046 cnd_delete(cnd_stop_timeout);
2047 if (cnd_ring_timeout != NULL)
2048 cnd_delete(cnd_ring_timeout);
2050 if ((cfile.save_file != NULL) && !quiet) {
2051 /* We're saving to a file, which means we're printing packet counts
2052 to stderr if we are not running silent and deep.
2053 Send a newline so that we move to the line after the packet count. */
2054 fprintf(stderr, "\n");
2057 /* If we got an error while capturing, report it. */
2061 if (ld.pipe_err == PIPERR) {
2062 fprintf(stderr, "tethereal: Error while capturing packets: %s\n",
2068 fprintf(stderr, "tethereal: Error while capturing packets: %s\n",
2069 pcap_geterr(ld.pch));
2073 if (volatile_err == 0)
2076 show_capture_file_io_error(cfile.save_file, volatile_err, FALSE);
2080 if (cfile.save_file != NULL) {
2081 /* We're saving to a file or files; close all files. */
2082 if (capture_opts.ringbuffer_on) {
2083 dump_ok = ringbuf_wtap_dump_close(&cfile, &err);
2085 dump_ok = wtap_dump_close(ld.pdh, &err);
2087 /* If we've displayed a message about a write error, there's no point
2088 in displaying another message about an error on close. */
2089 if (!dump_ok && !write_err)
2090 show_capture_file_io_error(cfile.save_file, err, TRUE);
2094 if (ld.from_pipe && pipe_fd >= 0)
2099 /* Get the capture statistics, and, if any packets were dropped, report
2101 if (pcap_stats(ld.pch, &stats) >= 0) {
2102 if (stats.ps_drop != 0) {
2103 fprintf(stderr, "%u packets dropped\n", stats.ps_drop);
2106 fprintf(stderr, "tethereal: Can't get packet-drop statistics: %s\n",
2107 pcap_geterr(ld.pch));
2112 /* Report the number of captured packets if not reported during capture
2113 and we are saving to a file. */
2119 if (capture_opts.ringbuffer_on) {
2120 ringbuf_error_cleanup();
2122 g_free(cfile.save_file);
2123 cfile.save_file = NULL;
2124 fprintf(stderr, "tethereal: %s\n", errmsg);
2140 capture_pcap_cb(guchar *user, const struct pcap_pkthdr *phdr,
2143 struct wtap_pkthdr whdr;
2144 union wtap_pseudo_header pseudo_header;
2145 loop_data *ld = (loop_data *) user;
2149 /* Convert from libpcap to Wiretap format.
2150 If that fails, ignore the packet (wtap_process_pcap_packet has
2151 written an error message). */
2152 pd = wtap_process_pcap_packet(ld->linktype, phdr, pd, &pseudo_header,
2159 * Prevent a SIGINFO handler from writing to stdout while we're
2160 * doing so; instead, have it just set a flag telling us to print
2161 * that information when we're done.
2164 #endif /* SIGINFO */
2166 /* The current packet may have arrived after a very long silence,
2167 * way past the time to switch files. In order not to have
2168 * the first packet of a new series of events as the last
2169 * [or only] packet in the file, switch before writing!
2171 if (cnd_ring_timeout != NULL && cnd_eval(cnd_ring_timeout)) {
2172 /* time elapsed for this ring file, switch to the next */
2173 if (ringbuf_switch_file(&cfile, &ld->pdh, &loop_err)) {
2174 /* File switch succeeded: reset the condition */
2175 cnd_reset(cnd_ring_timeout);
2177 /* File switch failed: stop here */
2178 /* XXX - we should do something with "loop_err" */
2183 if (!process_packet(&cfile, ld->pdh, 0, &whdr, &pseudo_header, pd, &err)) {
2184 /* Error writing to a capture file */
2186 /* We're capturing packets, so (if -q not specified) we're printing
2187 a count of packets captured; move to the line after the count. */
2188 fprintf(stderr, "\n");
2190 show_capture_file_io_error(cfile.save_file, err, FALSE);
2191 pcap_close(ld->pch);
2192 wtap_dump_close(ld->pdh, &err);
2198 * Allow SIGINFO handlers to write.
2203 * If a SIGINFO handler asked us to write out capture counts, do so.
2207 #endif /* SIGINFO */
2212 capture_cleanup(DWORD ctrltype _U_)
2214 /* CTRL_C_EVENT is sort of like SIGINT, CTRL_BREAK_EVENT is unique to
2215 Windows, CTRL_CLOSE_EVENT is sort of like SIGHUP, CTRL_LOGOFF_EVENT
2216 is also sort of like SIGHUP, and CTRL_SHUTDOWN_EVENT is sort of
2217 like SIGTERM at least when the machine's shutting down.
2219 For now, we handle them all as indications that we should clean up
2220 and quit, just as we handle SIGINT, SIGHUP, and SIGTERM in that
2223 However, as handlers run in a new thread, we can't just longjmp
2224 out; we have to set "ld.go" to FALSE, and must return TRUE so that
2225 no other handler - such as one that would terminate the process -
2228 XXX - for some reason, typing ^C to Tethereal, if you run this in
2229 a Cygwin console window in at least some versions of Cygwin,
2230 causes Tethereal to terminate immediately; this routine gets
2231 called, but the main loop doesn't get a chance to run and
2232 exit cleanly, at least if this is compiled with Microsoft Visual
2233 C++ (i.e., it's a property of the Cygwin console window or Bash;
2234 it happens if Tethereal is not built with Cygwin - for all I know,
2235 building it with Cygwin may make the problem go away). */
2241 capture_cleanup(int signum _U_)
2243 /* Longjmp back to the starting point; "pcap_dispatch()", on many
2244 UNIX platforms, just keeps looping if it gets EINTR, so if we set
2245 "ld.go" to FALSE and return, we won't break out of it and quit
2247 longjmp(ld.stopenv, 1);
2255 /* XXX - if we use sigaction, this doesn't have to be done.
2256 (Yes, this isn't necessary on BSD, but just in case a system
2257 where "signal()" has AT&T semantics adopts SIGINFO....) */
2258 signal(SIGINFO, report_counts_siginfo);
2259 #endif /* SIGINFO */
2261 if (quiet || print_packet_info) {
2262 /* Report the count only if we aren't printing a packet count
2263 as packets arrive. */
2264 fprintf(stderr, "%u packets captured\n", ld.packet_count);
2267 infoprint = FALSE; /* we just reported it */
2268 #endif /* SIGINFO */
2273 report_counts_siginfo(int signum _U_)
2275 int sav_errno = errno;
2276 /* If we've been told to delay printing, just set a flag asking
2277 that we print counts (if we're supposed to), otherwise print
2278 the count of packets captured (if we're supposed to). */
2285 #endif /* SIGINFO */
2286 #endif /* HAVE_LIBPCAP */
2289 load_cap_file(capture_file *cf, int out_file_type)
2292 int snapshot_length;
2298 linktype = wtap_file_encap(cf->wth);
2299 if (cf->save_file != NULL) {
2300 /* Set up to write to the capture file. */
2301 snapshot_length = wtap_snapshot_length(cf->wth);
2302 if (snapshot_length == 0) {
2303 /* Snapshot length of input file not known. */
2304 snapshot_length = WTAP_MAX_PACKET_SIZE;
2306 pdh = wtap_dump_open(cf->save_file, out_file_type,
2307 linktype, snapshot_length, &err);
2310 /* We couldn't set up to write to the capture file. */
2313 case WTAP_ERR_UNSUPPORTED_FILE_TYPE:
2315 "tethereal: Capture files can't be written in that format.\n");
2318 case WTAP_ERR_UNSUPPORTED_ENCAP:
2319 case WTAP_ERR_ENCAP_PER_PACKET_UNSUPPORTED:
2321 "tethereal: The capture file being read cannot be written in "
2325 case WTAP_ERR_CANT_OPEN:
2327 "tethereal: The file \"%s\" couldn't be created for some "
2328 "unknown reason.\n",
2329 *cf->save_file == '\0' ? "stdout" : cf->save_file);
2332 case WTAP_ERR_SHORT_WRITE:
2334 "tethereal: A full header couldn't be written to the file \"%s\".\n",
2335 *cf->save_file == '\0' ? "stdout" : cf->save_file);
2340 "tethereal: The file \"%s\" could not be created: %s\n.",
2341 *cf->save_file == '\0' ? "stdout" : cf->save_file,
2342 wtap_strerror(err));
2349 if (ferror(stdout)) {
2351 show_print_file_io_error(err);
2356 while (wtap_read(cf->wth, &err, &err_info, &data_offset)) {
2357 if (!process_packet(cf, pdh, data_offset, wtap_phdr(cf->wth),
2358 wtap_pseudoheader(cf->wth), wtap_buf_ptr(cf->wth),
2360 /* Error writing to a capture file */
2361 show_capture_file_io_error(cf->save_file, err, FALSE);
2362 wtap_dump_close(pdh, &err);
2367 /* Print a message noting that the read failed somewhere along the line. */
2370 case WTAP_ERR_UNSUPPORTED_ENCAP:
2372 "tethereal: \"%s\" has a packet with a network type that Tethereal doesn't support.\n(%s)\n",
2373 cf->filename, err_info);
2376 case WTAP_ERR_CANT_READ:
2378 "tethereal: An attempt to read from \"%s\" failed for some unknown reason.\n",
2382 case WTAP_ERR_SHORT_READ:
2384 "tethereal: \"%s\" appears to have been cut short in the middle of a packet.\n",
2388 case WTAP_ERR_BAD_RECORD:
2390 "tethereal: \"%s\" appears to be damaged or corrupt.\n(%s)\n",
2391 cf->filename, err_info);
2396 "tethereal: An error occurred while reading \"%s\": %s.\n",
2397 cf->filename, wtap_strerror(err));
2400 if (cf->save_file != NULL) {
2401 /* Now close the capture file. */
2402 if (!wtap_dump_close(pdh, &err))
2403 show_capture_file_io_error(cfile.save_file, err, TRUE);
2406 if (cf->save_file != NULL) {
2407 /* Now close the capture file. */
2408 if (!wtap_dump_close(pdh, &err))
2409 show_capture_file_io_error(cfile.save_file, err, TRUE);
2412 if (ferror(stdout)) {
2414 show_print_file_io_error(err);
2420 wtap_close(cf->wth);
2427 fill_in_fdata(frame_data *fdata, capture_file *cf,
2428 const struct wtap_pkthdr *phdr, long offset)
2433 fdata->num = cf->count;
2434 fdata->pkt_len = phdr->len;
2435 cum_bytes += phdr->len;
2436 fdata->cum_bytes = cum_bytes;
2437 fdata->cap_len = phdr->caplen;
2438 fdata->file_off = offset;
2439 fdata->lnk_t = phdr->pkt_encap;
2440 fdata->abs_secs = phdr->ts.tv_sec;
2441 fdata->abs_usecs = phdr->ts.tv_usec;
2442 fdata->flags.passed_dfilter = 0;
2443 fdata->flags.encoding = CHAR_ASCII;
2444 fdata->flags.visited = 0;
2445 fdata->flags.marked = 0;
2446 fdata->flags.ref_time = 0;
2448 /* If we don't have the time stamp of the first packet in the
2449 capture, it's because this is the first packet. Save the time
2450 stamp of this packet as the time stamp of the first packet. */
2451 if (!firstsec && !firstusec) {
2452 firstsec = fdata->abs_secs;
2453 firstusec = fdata->abs_usecs;
2456 /* If we don't have the time stamp of the previous displayed packet,
2457 it's because this is the first displayed packet. Save the time
2458 stamp of this packet as the time stamp of the previous displayed
2460 if (!prevsec && !prevusec) {
2461 prevsec = fdata->abs_secs;
2462 prevusec = fdata->abs_usecs;
2465 /* Get the time elapsed between the first packet and this packet. */
2466 compute_timestamp_diff(&fdata->rel_secs, &fdata->rel_usecs,
2467 fdata->abs_secs, fdata->abs_usecs, firstsec, firstusec);
2469 /* If it's greater than the current elapsed time, set the elapsed time
2470 to it (we check for "greater than" so as not to be confused by
2471 time moving backwards). */
2472 if ((gint32)cf->esec < fdata->rel_secs
2473 || ((gint32)cf->esec == fdata->rel_secs && (gint32)cf->eusec < fdata->rel_usecs)) {
2474 cf->esec = fdata->rel_secs;
2475 cf->eusec = fdata->rel_usecs;
2478 /* Get the time elapsed between the previous displayed packet and
2480 compute_timestamp_diff(&fdata->del_secs, &fdata->del_usecs,
2481 fdata->abs_secs, fdata->abs_usecs, prevsec, prevusec);
2482 prevsec = fdata->abs_secs;
2483 prevusec = fdata->abs_usecs;
2486 /* Free up all data attached to a "frame_data" structure. */
2488 clear_fdata(frame_data *fdata)
2491 g_slist_free(fdata->pfd);
2495 process_packet(capture_file *cf, wtap_dumper *pdh, long offset,
2496 const struct wtap_pkthdr *whdr,
2497 union wtap_pseudo_header *pseudo_header, const guchar *pd,
2501 gboolean create_proto_tree;
2502 epan_dissect_t *edt;
2505 /* Count this packet. */
2508 /* If we're going to print packet information, or we're going to
2509 run a read filter, or we're going to process taps, set up to
2510 do a dissection and do so. */
2511 if (do_dissection) {
2512 fill_in_fdata(&fdata, cf, whdr, offset);
2514 if (print_packet_info) {
2515 /* Grab any resolved addresses */
2517 if (g_resolv_flags) {
2518 host_name_lookup_process(NULL);
2523 if (cf->rfcode || verbose || num_tap_filters!=0)
2524 create_proto_tree = TRUE;
2526 create_proto_tree = FALSE;
2527 /* The protocol tree will be "visible", i.e., printed, only if we're
2528 printing packet details, which is true if we're printing stuff
2529 ("print_packet_info" is true) and we're in verbose mode ("verbose"
2531 edt = epan_dissect_new(create_proto_tree, print_packet_info && verbose);
2533 /* If we're running a read filter, prime the epan_dissect_t with that
2536 epan_dissect_prime_dfilter(edt, cf->rfcode);
2538 tap_queue_init(edt);
2540 /* We only need the columns if we're printing packet info but we're
2541 *not* verbose; in verbose mode, we print the protocol tree, not
2542 the protocol summary. */
2543 epan_dissect_run(edt, pseudo_header, pd, &fdata,
2544 (print_packet_info && !verbose) ? &cf->cinfo : NULL);
2546 tap_push_tapped_queue(edt);
2548 /* Run the read filter if we have one. */
2550 passed = dfilter_apply_edt(cf->rfcode, edt);
2554 /* We're not running a display filter and we're not printing any
2555 packet information, so we don't need to do a dissection, and all
2556 packets are processed. */
2562 /* Count this packet. */
2567 /* Process this packet. */
2569 /* We're writing to a capture file; write this packet. */
2570 if (!wtap_dump(pdh, whdr, pseudo_header, pd, err))
2572 /* Report packet capture count if not quiet */
2573 if (!quiet && !print_packet_info) {
2574 /* Don't print a packet count if we were asked not to with "-q"
2575 or if we're also printing packet info. */
2576 if (ld.packet_count != 0) {
2577 fprintf(stderr, "\r%u ", ld.packet_count);
2578 /* stderr could be line buffered */
2583 if (print_packet_info) {
2584 /* We're printing packet information; print the information for
2586 print_packet(cf, edt);
2588 /* The ANSI C standard does not appear to *require* that a line-buffered
2589 stream be flushed to the host environment whenever a newline is
2590 written, it just says that, on such a stream, characters "are
2591 intended to be transmitted to or from the host environment as a
2592 block when a new-line character is encountered".
2594 The Visual C++ 6.0 C implementation doesn't do what is intended;
2595 even if you set a stream to be line-buffered, it still doesn't
2596 flush the buffer at the end of every line.
2598 So, if the "-l" flag was specified, we flush the standard output
2599 at the end of a packet. This will do the right thing if we're
2600 printing packet summary lines, and, as we print the entire protocol
2601 tree for a single packet without waiting for anything to happen,
2602 it should be as good as line-buffered mode if we're printing
2603 protocol trees. (The whole reason for the "-l" flag in either
2604 tcpdump or Tethereal is to allow the output of a live capture to
2605 be piped to a program or script and to have that script see the
2606 information for the packet as soon as it's printed, rather than
2607 having to wait until a standard I/O buffer fills up. */
2611 if (ferror(stdout)) {
2612 show_print_file_io_error(errno);
2618 if (do_dissection) {
2619 epan_dissect_free(edt);
2620 clear_fdata(&fdata);
2626 show_capture_file_io_error(const char *fname, int err, gboolean is_close)
2635 "tethereal: Not all the packets could be written to \"%s\" because there is "
2636 "no space left on the file system.\n",
2643 "tethereal: Not all the packets could be written to \"%s\" because you are "
2644 "too close to, or over your disk quota.\n",
2649 case WTAP_ERR_CANT_CLOSE:
2651 "tethereal: \"%s\" couldn't be closed for some unknown reason.\n",
2655 case WTAP_ERR_SHORT_WRITE:
2657 "tethereal: Not all the packets could be written to \"%s\".\n",
2664 "tethereal: \"%s\" could not be closed: %s.\n",
2665 fname, wtap_strerror(err));
2668 "tethereal: An error occurred while writing to \"%s\": %s.\n",
2669 fname, wtap_strerror(err));
2676 write_preamble(capture_file *cf)
2678 switch (output_action) {
2681 print_preamble(stdout, print_format, cf->filename);
2686 write_pdml_preamble(stdout);
2688 write_psml_preamble(stdout);
2694 print_columns(capture_file *cf)
2698 for (i = 0; i < cf->cinfo.num_cols; i++) {
2699 switch (cf->cinfo.col_fmt[i]) {
2702 * Don't print this if we're doing a live capture from a network
2703 * interface - if we're doing a live capture, you won't be
2704 * able to look at the capture in the future (it's not being
2705 * saved anywhere), so the frame numbers are unlikely to be
2708 * (XXX - it might be nice to be able to save and print at
2709 * the same time, sort of like an "Update list of packets
2710 * in real time" capture in Ethereal.)
2712 if (cf->iface != NULL)
2714 printf("%3s", cf->cinfo.col_data[i]);
2720 case COL_ABS_DATE_TIME: /* XXX - wider */
2721 printf("%10s", cf->cinfo.col_data[i]);
2727 case COL_DEF_DL_SRC:
2728 case COL_RES_DL_SRC:
2729 case COL_UNRES_DL_SRC:
2730 case COL_DEF_NET_SRC:
2731 case COL_RES_NET_SRC:
2732 case COL_UNRES_NET_SRC:
2733 printf("%12s", cf->cinfo.col_data[i]);
2739 case COL_DEF_DL_DST:
2740 case COL_RES_DL_DST:
2741 case COL_UNRES_DL_DST:
2742 case COL_DEF_NET_DST:
2743 case COL_RES_NET_DST:
2744 case COL_UNRES_NET_DST:
2745 printf("%-12s", cf->cinfo.col_data[i]);
2749 printf("%s", cf->cinfo.col_data[i]);
2752 if (i != cf->cinfo.num_cols - 1) {
2754 * This isn't the last column, so we need to print a
2755 * separator between this column and the next.
2757 * If we printed a network source and are printing a
2758 * network destination of the same type next, separate
2759 * them with "->"; if we printed a network destination
2760 * and are printing a network source of the same type
2761 * next, separate them with "<-"; otherwise separate them
2764 switch (cf->cinfo.col_fmt[i]) {
2769 switch (cf->cinfo.col_fmt[i + 1]) {
2783 case COL_DEF_DL_SRC:
2784 case COL_RES_DL_SRC:
2785 case COL_UNRES_DL_SRC:
2786 switch (cf->cinfo.col_fmt[i + 1]) {
2788 case COL_DEF_DL_DST:
2789 case COL_RES_DL_DST:
2790 case COL_UNRES_DL_DST:
2800 case COL_DEF_NET_SRC:
2801 case COL_RES_NET_SRC:
2802 case COL_UNRES_NET_SRC:
2803 switch (cf->cinfo.col_fmt[i + 1]) {
2805 case COL_DEF_NET_DST:
2806 case COL_RES_NET_DST:
2807 case COL_UNRES_NET_DST:
2820 switch (cf->cinfo.col_fmt[i + 1]) {
2834 case COL_DEF_DL_DST:
2835 case COL_RES_DL_DST:
2836 case COL_UNRES_DL_DST:
2837 switch (cf->cinfo.col_fmt[i + 1]) {
2839 case COL_DEF_DL_SRC:
2840 case COL_RES_DL_SRC:
2841 case COL_UNRES_DL_SRC:
2851 case COL_DEF_NET_DST:
2852 case COL_RES_NET_DST:
2853 case COL_UNRES_NET_DST:
2854 switch (cf->cinfo.col_fmt[i + 1]) {
2856 case COL_DEF_NET_SRC:
2857 case COL_RES_NET_SRC:
2858 case COL_UNRES_NET_SRC:
2878 print_packet(capture_file *cf, epan_dissect_t *edt)
2880 print_args_t print_args;
2883 /* Print the information in the protocol tree. */
2884 switch (output_action) {
2887 print_args.to_file = TRUE;
2888 print_args.format = print_format;
2889 print_args.print_summary = !verbose;
2890 print_args.print_hex = verbose && print_hex;
2891 print_args.print_formfeed = FALSE;
2892 print_args.print_dissections = verbose ? print_dissections_expanded : print_dissections_none;
2894 /* init the packet range */
2895 packet_range_init(&print_args.range);
2897 proto_tree_print(&print_args, edt, stdout);
2901 proto_tree_write_pdml(edt, stdout);
2905 /* "print_hex_data()" will put out a leading blank line, as well
2906 as a trailing one; print one here, to separate the packets,
2907 only if "print_hex_data()" won't be called. */
2911 /* Just fill in the columns. */
2912 epan_dissect_fill_in_columns(edt);
2914 /* Now print them. */
2915 switch (output_action) {
2922 proto_tree_write_psml(edt, stdout);
2927 print_hex_data(stdout, print_format, edt);
2935 switch (output_action) {
2938 print_finale(stdout, print_format);
2943 write_pdml_finale(stdout);
2945 write_psml_finale(stdout);
2951 show_print_file_io_error(int err)
2957 "tethereal: Not all the packets could be printed because there is "
2958 "no space left on the file system.\n");
2964 "tethereal: Not all the packets could be printed because you are "
2965 "too close to, or over your disk quota.\n");
2971 "tethereal: An error occurred while printing packets: %s.\n",
2978 cf_open_error_message(int err, gchar *err_info, gboolean for_writing,
2982 static char errmsg_errno[1024+1];
2985 /* Wiretap error. */
2988 case WTAP_ERR_NOT_REGULAR_FILE:
2989 errmsg = "The file \"%s\" is a \"special file\" or socket or other non-regular file.";
2992 case WTAP_ERR_FILE_UNKNOWN_FORMAT:
2993 /* Seen only when opening a capture file for reading. */
2994 errmsg = "The file \"%s\" is not a capture file in a format Tethereal understands.";
2997 case WTAP_ERR_UNSUPPORTED:
2998 /* Seen only when opening a capture file for reading. */
2999 snprintf(errmsg_errno, sizeof(errmsg_errno),
3000 "The file \"%%s\" is not a capture file in a format Tethereal understands.\n"
3003 errmsg = errmsg_errno;
3006 case WTAP_ERR_CANT_WRITE_TO_PIPE:
3007 /* Seen only when opening a capture file for writing. */
3008 snprintf(errmsg_errno, sizeof(errmsg_errno),
3009 "The file \"%%s\" is a pipe, and %s capture files cannot be "
3010 "written to a pipe.", wtap_file_type_string(file_type));
3011 errmsg = errmsg_errno;
3014 case WTAP_ERR_UNSUPPORTED_FILE_TYPE:
3015 /* Seen only when opening a capture file for writing. */
3016 errmsg = "Tethereal does not support writing capture files in that format.";
3019 case WTAP_ERR_UNSUPPORTED_ENCAP:
3021 errmsg = "Tethereal cannot save this capture in that format.";
3023 snprintf(errmsg_errno, sizeof(errmsg_errno),
3024 "The file \"%%s\" is a capture for a network type that Tethereal doesn't support.\n"
3027 errmsg = errmsg_errno;
3031 case WTAP_ERR_ENCAP_PER_PACKET_UNSUPPORTED:
3033 errmsg = "Tethereal cannot save this capture in that format.";
3035 errmsg = "The file \"%s\" is a capture for a network type that Tethereal doesn't support.";
3038 case WTAP_ERR_BAD_RECORD:
3039 /* Seen only when opening a capture file for reading. */
3040 snprintf(errmsg_errno, sizeof(errmsg_errno),
3041 "The file \"%%s\" appears to be damaged or corrupt.\n"
3044 errmsg = errmsg_errno;
3047 case WTAP_ERR_CANT_OPEN:
3049 errmsg = "The file \"%s\" could not be created for some unknown reason.";
3051 errmsg = "The file \"%s\" could not be opened for some unknown reason.";
3054 case WTAP_ERR_SHORT_READ:
3055 errmsg = "The file \"%s\" appears to have been cut short"
3056 " in the middle of a packet or other data.";
3059 case WTAP_ERR_SHORT_WRITE:
3060 errmsg = "A full header couldn't be written to the file \"%s\".";
3064 snprintf(errmsg_errno, sizeof(errmsg_errno),
3065 "The file \"%%s\" could not be %s: %s.",
3066 for_writing ? "created" : "opened",
3067 wtap_strerror(err));
3068 errmsg = errmsg_errno;
3072 errmsg = file_open_error_message(err, for_writing);
3077 * Open/create errors are reported with an console message in Tethereal.
3080 open_failure_message(const char *filename, int err, gboolean for_writing)
3082 fprintf(stderr, "tethereal: ");
3083 fprintf(stderr, file_open_error_message(err, for_writing), filename);
3084 fprintf(stderr, "\n");
3088 cf_open(char *fname, gboolean is_tempfile, capture_file *cf)
3093 char err_msg[2048+1];
3095 wth = wtap_open_offline(fname, &err, &err_info, FALSE);
3099 /* The open succeeded. Fill in the information for this file. */
3101 /* Initialize all data structures used for dissection. */
3105 cf->filed = -1; /* not used, but set it anyway */
3106 cf->f_len = 0; /* not used, but set it anyway */
3108 /* Set the file name because we need it to set the follow stream filter.
3109 XXX - is that still true? We need it for other reasons, though,
3111 cf->filename = g_strdup(fname);
3113 /* Indicate whether it's a permanent or temporary file. */
3114 cf->is_tempfile = is_tempfile;
3116 /* If it's a temporary capture buffer file, mark it as not saved. */
3117 cf->user_saved = !is_tempfile;
3119 cf->cd_t = wtap_file_type(cf->wth);
3121 cf->drops_known = FALSE;
3125 cf->snap = wtap_snapshot_length(cf->wth);
3126 if (cf->snap == 0) {
3127 /* Snapshot length not known. */
3128 cf->has_snap = FALSE;
3129 cf->snap = WTAP_MAX_PACKET_SIZE;
3131 cf->has_snap = TRUE;
3132 firstsec = 0, firstusec = 0;
3133 prevsec = 0, prevusec = 0;
3138 snprintf(err_msg, sizeof err_msg,
3139 cf_open_error_message(err, err_info, FALSE, 0), fname);
3140 fprintf(stderr, "tethereal: %s\n", err_msg);
3146 /* Take care of byte order in the libpcap headers read from pipes.
3147 * (function taken from wiretap/libpcap.c) */
3149 adjust_header(loop_data *ld, struct pcap_hdr *hdr, struct pcaprec_hdr *rechdr)
3151 if (ld->byte_swapped) {
3152 /* Byte-swap the record header fields. */
3153 rechdr->ts_sec = BSWAP32(rechdr->ts_sec);
3154 rechdr->ts_usec = BSWAP32(rechdr->ts_usec);
3155 rechdr->incl_len = BSWAP32(rechdr->incl_len);
3156 rechdr->orig_len = BSWAP32(rechdr->orig_len);
3159 /* In file format version 2.3, the "incl_len" and "orig_len" fields were
3160 swapped, in order to match the BPF header layout.
3162 Unfortunately, some files were, according to a comment in the "libpcap"
3163 source, written with version 2.3 in their headers but without the
3164 interchanged fields, so if "incl_len" is greater than "orig_len" - which
3165 would make no sense - we assume that we need to swap them. */
3166 if (hdr->version_major == 2 &&
3167 (hdr->version_minor < 3 ||
3168 (hdr->version_minor == 3 && rechdr->incl_len > rechdr->orig_len))) {
3171 temp = rechdr->orig_len;
3172 rechdr->orig_len = rechdr->incl_len;
3173 rechdr->incl_len = temp;
3177 /* Mimic pcap_open_live() for pipe captures
3178 * We check if "pipename" is "-" (stdin) or a FIFO, open it, and read the
3180 * N.B. : we can't read the libpcap formats used in RedHat 6.1 or SuSE 6.3
3181 * because we can't seek on pipes (see wiretap/libpcap.c for details) */
3183 pipe_open_live(char *pipename, struct pcap_hdr *hdr, loop_data *ld,
3184 char *errmsg, int errmsgl)
3186 struct stat pipe_stat;
3190 unsigned int bytes_read;
3193 * XXX Tethereal blocks until we return
3195 if (strcmp(pipename, "-") == 0)
3196 fd = 0; /* read from stdin */
3198 if (stat(pipename, &pipe_stat) < 0) {
3199 if (errno == ENOENT || errno == ENOTDIR)
3200 ld->pipe_err = PIPNEXIST;
3202 snprintf(errmsg, errmsgl,
3203 "The capture session could not be initiated "
3204 "due to error on pipe: %s", strerror(errno));
3205 ld->pipe_err = PIPERR;
3209 if (! S_ISFIFO(pipe_stat.st_mode)) {
3210 if (S_ISCHR(pipe_stat.st_mode)) {
3212 * Assume the user specified an interface on a system where
3213 * interfaces are in /dev. Pretend we haven't seen it.
3215 ld->pipe_err = PIPNEXIST;
3217 snprintf(errmsg, errmsgl,
3218 "The capture session could not be initiated because\n"
3219 "\"%s\" is neither an interface nor a pipe", pipename);
3220 ld->pipe_err = PIPERR;
3224 fd = open(pipename, O_RDONLY);
3226 snprintf(errmsg, errmsgl,
3227 "The capture session could not be initiated "
3228 "due to error on pipe open: %s", strerror(errno));
3229 ld->pipe_err = PIPERR;
3234 ld->from_pipe = TRUE;
3236 /* read the pcap header */
3238 while (bytes_read < sizeof magic) {
3239 b = read(fd, ((char *)&magic)+bytes_read, sizeof magic-bytes_read);
3242 snprintf(errmsg, errmsgl, "End of file on pipe during open");
3244 snprintf(errmsg, errmsgl, "Error on pipe during open: %s",
3253 /* Host that wrote it has our byte order, and was running
3254 a program using either standard or ss990417 libpcap. */
3255 ld->byte_swapped = FALSE;
3256 ld->modified = FALSE;
3258 case PCAP_MODIFIED_MAGIC:
3259 /* Host that wrote it has our byte order, but was running
3260 a program using either ss990915 or ss991029 libpcap. */
3261 ld->byte_swapped = FALSE;
3262 ld->modified = TRUE;
3264 case PCAP_SWAPPED_MAGIC:
3265 /* Host that wrote it has a byte order opposite to ours,
3266 and was running a program using either standard or
3267 ss990417 libpcap. */
3268 ld->byte_swapped = TRUE;
3269 ld->modified = FALSE;
3271 case PCAP_SWAPPED_MODIFIED_MAGIC:
3272 /* Host that wrote it out has a byte order opposite to
3273 ours, and was running a program using either ss990915
3274 or ss991029 libpcap. */
3275 ld->byte_swapped = TRUE;
3276 ld->modified = TRUE;
3279 /* Not a "libpcap" type we know about. */
3280 snprintf(errmsg, errmsgl, "Unrecognized libpcap format");
3284 /* Read the rest of the header */
3286 while (bytes_read < sizeof(struct pcap_hdr)) {
3287 b = read(fd, ((char *)hdr)+bytes_read,
3288 sizeof(struct pcap_hdr) - bytes_read);
3291 snprintf(errmsg, errmsgl, "End of file on pipe during open");
3293 snprintf(errmsg, errmsgl, "Error on pipe during open: %s",
3300 if (ld->byte_swapped) {
3301 /* Byte-swap the header fields about which we care. */
3302 hdr->version_major = BSWAP16(hdr->version_major);
3303 hdr->version_minor = BSWAP16(hdr->version_minor);
3304 hdr->snaplen = BSWAP32(hdr->snaplen);
3305 hdr->network = BSWAP32(hdr->network);
3308 if (hdr->version_major < 2) {
3309 snprintf(errmsg, errmsgl, "Unable to read old libpcap format");
3313 ld->pipe_state = STATE_EXPECT_REC_HDR;
3314 ld->pipe_err = PIPOK;
3318 ld->pipe_err = PIPERR;
3323 /* We read one record from the pipe, take care of byte order in the record
3324 * header, write the record in the capture file, and update capture statistics. */
3327 pipe_dispatch(int fd, loop_data *ld, struct pcap_hdr *hdr,
3328 struct pcaprec_modified_hdr *rechdr, guchar *data,
3329 char *errmsg, int errmsgl)
3331 struct pcap_pkthdr phdr;
3333 enum { PD_REC_HDR_READ, PD_DATA_READ, PD_PIPE_EOF, PD_PIPE_ERR,
3336 switch (ld->pipe_state) {
3338 case STATE_EXPECT_REC_HDR:
3339 ld->bytes_to_read = ld->modified ?
3340 sizeof(struct pcaprec_modified_hdr) : sizeof(struct pcaprec_hdr);
3342 ld->pipe_state = STATE_READ_REC_HDR;
3345 case STATE_READ_REC_HDR:
3346 b = read(fd, ((char *)rechdr)+ld->bytes_read,
3347 ld->bytes_to_read - ld->bytes_read);
3350 result = PD_PIPE_EOF;
3352 result = PD_PIPE_ERR;
3355 if ((ld->bytes_read += b) < ld->bytes_to_read)
3357 result = PD_REC_HDR_READ;
3360 case STATE_EXPECT_DATA:
3362 ld->pipe_state = STATE_READ_DATA;
3365 case STATE_READ_DATA:
3366 b = read(fd, data+ld->bytes_read, rechdr->hdr.incl_len - ld->bytes_read);
3369 result = PD_PIPE_EOF;
3371 result = PD_PIPE_ERR;
3374 if ((ld->bytes_read += b) < rechdr->hdr.incl_len)
3376 result = PD_DATA_READ;
3380 snprintf(errmsg, errmsgl, "pipe_dispatch: invalid state");
3383 } /* switch (ld->pipe_state) */
3386 * We've now read as much data as we were expecting, so process it.
3390 case PD_REC_HDR_READ:
3391 /* We've read the header. Take care of byte order. */
3392 adjust_header(ld, hdr, &rechdr->hdr);
3393 if (rechdr->hdr.incl_len > WTAP_MAX_PACKET_SIZE) {
3394 snprintf(errmsg, errmsgl, "Frame %u too long (%d bytes)",
3395 ld->packet_count+1, rechdr->hdr.incl_len);
3398 ld->pipe_state = STATE_EXPECT_DATA;
3402 /* Fill in a "struct pcap_pkthdr", and process the packet. */
3403 phdr.ts.tv_sec = rechdr->hdr.ts_sec;
3404 phdr.ts.tv_usec = rechdr->hdr.ts_usec;
3405 phdr.caplen = rechdr->hdr.incl_len;
3406 phdr.len = rechdr->hdr.orig_len;
3408 capture_pcap_cb((guchar *)ld, &phdr, data);
3410 ld->pipe_state = STATE_EXPECT_REC_HDR;
3414 ld->pipe_err = PIPEOF;
3418 snprintf(errmsg, errmsgl, "Error reading from pipe: %s",
3425 ld->pipe_err = PIPERR;
3426 /* Return here rather than inside the switch to prevent GCC warning */
3430 #endif /* HAVE_LIBPCAP */
3433 * General errors are reported with an console message in Tethereal.
3436 failure_message(const char *msg_format, va_list ap)
3438 fprintf(stderr, "tethereal: ");
3439 vfprintf(stderr, msg_format, ap);
3440 fprintf(stderr, "\n");
3444 * Read errors are reported with an console message in Tethereal.
3447 read_failure_message(const char *filename, int err)
3449 fprintf(stderr, "tethereal: An error occurred while reading from the file \"%s\": %s.\n",
3450 filename, strerror(err));