2 * Routines for packet capture windows
6 * Ethereal - Network traffic analyzer
7 * By Gerald Combs <gerald@ethereal.com>
8 * Copyright 1998 Gerald Combs
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.
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.
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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25 /* With MSVC and a libethereal.dll this file needs to import some variables
26 in a special way. Therefore _NEED_VAR_IMPORT_ is defined. */
27 #define _NEED_VAR_IMPORT_
35 #ifdef HAVE_SYS_STAT_H
36 # include <sys/stat.h>
39 #ifdef HAVE_SYS_WAIT_H
40 # include <sys/wait.h>
45 * Define various POSIX macros (and, in the case of WCOREDUMP, non-POSIX
46 * macros) on UNIX systems that don't have them.
49 # define WIFEXITED(status) (((status) & 0177) == 0)
52 # define WIFSTOPPED(status) (((status) & 0177) == 0177)
55 # define WIFSIGNALED(status) (!WIFSTOPPED(status) && !WIFEXITED(status))
58 # define WEXITSTATUS(status) ((status) >> 8)
61 # define WTERMSIG(status) ((status) & 0177)
64 # define WCOREDUMP(status) ((status) & 0200)
67 # define WSTOPSIG(status) ((status) >> 8)
93 #ifdef HAVE_SYS_SOCKET_H
94 #include <sys/socket.h>
97 #ifdef HAVE_SYS_IOCTL_H
98 #include <sys/ioctl.h>
104 #ifdef NEED_SNPRINTF_H
105 # include "snprintf.h"
109 #include <process.h> /* For spawning child process */
113 * We don't want to do a "select()" on the pcap_t's file descriptor on
114 * BSD (because "select()" doesn't work correctly on BPF devices on at
115 * least some releases of some flavors of BSD), and we don't want to do
116 * it on Windows (because "select()" is something for sockets, not for
117 * arbitrary handles). (Note that "Windows" here includes Cygwin;
118 * even in its pretend-it's-UNIX environment, we're using WinPcap, not
121 * We *do* want to do it on other platforms, as, on other platforms (with
122 * the possible exception of Ultrix and Digital UNIX), the read timeout
123 * doesn't expire if no packets have arrived, so a "pcap_dispatch()" call
124 * will block until packets arrive, causing the UI to hang.
126 * XXX - the various BSDs appear to define BSD in <sys/param.h>; we don't
127 * want to include it if it's not present on this platform, however.
129 #if !defined(__FreeBSD__) && !defined(__NetBSD__) && !defined(__OpenBSD__) && \
130 !defined(__bsdi__) && !defined(__APPLE__) && !defined(_WIN32) && \
132 # define MUST_DO_SELECT
135 #include <epan/packet.h>
136 #include <epan/dfilter/dfilter.h>
140 #include "pcap-util.h"
141 #include "alert_box.h"
142 #include "simple_dialog.h"
145 #include "conditions.h"
146 #include "capture_stop_conditions.h"
147 #include "ringbuffer.h"
149 #include "wiretap/libpcap.h"
150 #include "wiretap/wtap.h"
151 #include "wiretap/wtap-capture.h"
153 #include <epan/dissectors/packet-ap1394.h>
154 #include <epan/dissectors/packet-atalk.h>
155 #include <epan/dissectors/packet-atm.h>
156 #include <epan/dissectors/packet-clip.h>
157 #include <epan/dissectors/packet-eth.h>
158 #include <epan/dissectors/packet-fddi.h>
159 #include <epan/dissectors/packet-null.h>
160 #include <epan/dissectors/packet-ppp.h>
161 #include <epan/dissectors/packet-raw.h>
162 #include <epan/dissectors/packet-sll.h>
163 #include <epan/dissectors/packet-tr.h>
164 #include <epan/dissectors/packet-ieee80211.h>
165 #include <epan/dissectors/packet-chdlc.h>
166 #include <epan/dissectors/packet-prism.h>
167 #include <epan/dissectors/packet-ipfc.h>
168 #include <epan/dissectors/packet-arcnet.h>
171 #include "capture-wpcap.h"
178 capture_options capture_opts;
179 gboolean quit_after_cap = FALSE;/* Makes a "capture only mode". Implies -k */
180 gboolean capture_child; /* if this is the child for "-S" */
182 static int sync_pipe[2]; /* used to sync father */
183 enum PIPES { READ, WRITE }; /* Constants 0 and 1 for READ and WRITE */
184 static int fork_child = -1; /* If not -1, in parent, process ID of child */
186 /* Size of buffer to hold decimal representation of
187 signed/unsigned 64-bit int */
188 #define SP_DECISIZE 20
191 * Indications sent out on the sync pipe.
193 #define SP_CAPSTART ';' /* capture start message */
194 #define SP_PACKET_COUNT '*' /* followed by count of packets captured since last message */
195 #define SP_ERROR_MSG '!' /* followed by length of error message that follows */
196 #define SP_DROPS '#' /* followed by count of packets dropped in capture */
199 typedef struct _loop_data {
200 gboolean go; /* TRUE as long as we're supposed to keep capturing */
201 gint max; /* Number of packets we're supposed to capture - 0 means infinite */
202 int err; /* if non-zero, error seen while capturing */
205 gboolean pcap_err; /* TRUE if error from pcap */
206 gboolean from_cap_pipe;/* TRUE if we are capturing data from a pipe */
207 packet_counts counts;
210 gboolean modified; /* TRUE if data in the pipe uses modified pcap headers */
211 gboolean byte_swapped; /* TRUE if data in the pipe is byte swapped */
212 unsigned int bytes_to_read, bytes_read; /* Used by cap_pipe_dispatch */
214 STATE_EXPECT_REC_HDR, STATE_READ_REC_HDR,
215 STATE_EXPECT_DATA, STATE_READ_DATA
218 enum { PIPOK, PIPEOF, PIPERR, PIPNEXIST } cap_pipe_err;
222 /* Win32 needs the O_BINARY flag for open() */
227 static gboolean sync_pipe_do_capture(gboolean is_tempfile);
228 static gboolean sync_pipe_input_cb(gint source, gpointer user_data);
229 static void sync_pipe_wait_for_child(gboolean);
230 static void sync_pipe_errmsg_to_parent(const char *);
232 static char *sync_pipe_signame(int);
235 static gboolean normal_do_capture(gboolean is_tempfile);
236 static void capture_pcap_cb(guchar *, const struct pcap_pkthdr *,
238 static void get_capture_file_io_error(char *, int, const char *, int, gboolean);
239 static void popup_errmsg(const char *);
240 static void stop_capture_signal_handler(int signo);
243 static void cap_pipe_adjust_header(loop_data *, struct pcap_hdr *, struct pcaprec_hdr *);
244 static int cap_pipe_open_live(char *, struct pcap_hdr *, loop_data *, char *, int);
245 static int cap_pipe_dispatch(int, loop_data *, struct pcap_hdr *, \
246 struct pcaprec_modified_hdr *, guchar *, char *, int);
254 /* Open a specified file, or create a temporary file, and start a capture
255 to the file in question. Returns TRUE if the capture starts
256 successfully, FALSE otherwise. */
258 do_capture(const char *save_file)
261 gboolean is_tempfile;
265 if (save_file != NULL) {
266 /* If the Sync option is set, we return to the caller while the capture
267 * is in progress. Therefore we need to take a copy of save_file in
268 * case the caller destroys it after we return.
270 capfile_name = g_strdup(save_file);
271 if (capture_opts.multi_files_on) {
272 /* ringbuffer is enabled */
273 cfile.save_file_fd = ringbuf_init(capfile_name,
274 (capture_opts.has_ring_num_files) ? capture_opts.ring_num_files : 0);
276 /* Try to open/create the specified file for use as a capture buffer. */
277 cfile.save_file_fd = open(capfile_name, O_RDWR|O_BINARY|O_TRUNC|O_CREAT,
282 /* Choose a random name for the capture buffer */
283 cfile.save_file_fd = create_tempfile(tmpname, sizeof tmpname, "ether");
284 capfile_name = g_strdup(tmpname);
287 if (cfile.save_file_fd == -1) {
289 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK,
290 "The temporary file to which the capture would be saved (\"%s\")"
291 "could not be opened: %s.", capfile_name, strerror(errno));
293 if (capture_opts.multi_files_on) {
294 ringbuf_error_cleanup();
296 open_failure_alert_box(capfile_name, errno, TRUE);
298 g_free(capfile_name);
302 g_assert(cfile.save_file == NULL);
303 cfile.save_file = capfile_name;
304 /* cfile.save_file is "g_free"ed below, which is equivalent to
305 "g_free(capfile_name)". */
308 if (capture_opts.sync_mode) {
309 /* sync mode: do the capture in a child process */
310 ret = sync_pipe_do_capture(is_tempfile);
311 /* capture is still running */
312 set_main_window_name("(Live Capture in Progress) - Ethereal");
314 /* normal mode: do the capture synchronously */
315 set_main_window_name("(Live Capture in Progress) - Ethereal");
316 ret = normal_do_capture(is_tempfile);
317 /* capture is finished here */
325 /* Add a string pointer to a NULL-terminated array of string pointers. */
327 sync_pipe_add_arg(char **args, int *argc, char *arg)
329 /* Grow the array; "*argc" currently contains the number of string
330 pointers, *not* counting the NULL pointer at the end, so we have
331 to add 2 in order to get the new size of the array, including the
332 new pointer and the terminating NULL pointer. */
333 args = g_realloc(args, (*argc + 2) * sizeof (char *));
335 /* Stuff the pointer into the penultimate element of the array, which
336 is the one at the index specified by "*argc". */
339 /* Now bump the count. */
342 /* We overwrite the NULL pointer; put it back right after the
350 /* Given a string, return a pointer to a quote-encapsulated version of
351 the string, so we can pass it as an argument with "spawnvp" even
352 if it contains blanks. */
354 sync_pipe_quote_encapsulate(const char *string)
356 char *encapsulated_string;
358 encapsulated_string = g_new(char, strlen(string) + 3);
359 sprintf(encapsulated_string, "\"%s\"", string);
360 return encapsulated_string;
367 sync_pipe_do_capture(gboolean is_tempfile) {
374 char scount[24]; /* need a constant for len of numbers */
375 char sautostop_filesize[24]; /* need a constant for len of numbers */
376 char sautostop_duration[24]; /* need a constant for len of numbers */
377 char save_file_fd[24];
385 char sync_pipe_fd[24];
390 /* Allocate the string pointer array with enough space for the
391 terminating NULL pointer. */
393 argv = g_malloc(sizeof (char *));
396 /* Now add those arguments used on all platforms. */
397 argv = sync_pipe_add_arg(argv, &argc, CHILD_NAME);
399 argv = sync_pipe_add_arg(argv, &argc, "-i");
400 argv = sync_pipe_add_arg(argv, &argc, cfile.iface);
402 argv = sync_pipe_add_arg(argv, &argc, "-w");
403 argv = sync_pipe_add_arg(argv, &argc, cfile.save_file);
405 argv = sync_pipe_add_arg(argv, &argc, "-W");
406 sprintf(save_file_fd,"%d",cfile.save_file_fd); /* in lieu of itoa */
407 argv = sync_pipe_add_arg(argv, &argc, save_file_fd);
409 if (capture_opts.has_autostop_packets) {
410 argv = sync_pipe_add_arg(argv, &argc, "-c");
411 sprintf(scount,"%d",capture_opts.autostop_packets);
412 argv = sync_pipe_add_arg(argv, &argc, scount);
415 if (capture_opts.has_snaplen) {
416 argv = sync_pipe_add_arg(argv, &argc, "-s");
417 sprintf(ssnap,"%d",capture_opts.snaplen);
418 argv = sync_pipe_add_arg(argv, &argc, ssnap);
421 if (capture_opts.linktype != -1) {
422 argv = sync_pipe_add_arg(argv, &argc, "-y");
423 sprintf(ssnap,"%d",capture_opts.linktype);
424 argv = sync_pipe_add_arg(argv, &argc, ssnap);
427 if (capture_opts.has_autostop_filesize) {
428 argv = sync_pipe_add_arg(argv, &argc, "-a");
429 sprintf(sautostop_filesize,"filesize:%d",capture_opts.autostop_filesize);
430 argv = sync_pipe_add_arg(argv, &argc, sautostop_filesize);
433 if (capture_opts.has_autostop_duration) {
434 argv = sync_pipe_add_arg(argv, &argc, "-a");
435 sprintf(sautostop_duration,"duration:%d",capture_opts.autostop_duration);
436 argv = sync_pipe_add_arg(argv, &argc, sautostop_duration);
439 if (!capture_opts.show_info) {
440 argv = sync_pipe_add_arg(argv, &argc, "-H");
443 if (!capture_opts.promisc_mode)
444 argv = sync_pipe_add_arg(argv, &argc, "-p");
447 /* Create a pipe for the child process */
449 if(_pipe(sync_pipe, 512, O_BINARY) < 0) {
450 /* Couldn't create the pipe between parent and child. */
452 unlink(cfile.save_file);
453 g_free(cfile.save_file);
454 cfile.save_file = NULL;
455 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK, "Couldn't create sync pipe: %s",
460 /* Convert font name to a quote-encapsulated string and pass to child */
461 argv = sync_pipe_add_arg(argv, &argc, "-m");
462 fontstring = sync_pipe_quote_encapsulate(prefs.PREFS_GUI_FONT_NAME);
463 argv = sync_pipe_add_arg(argv, &argc, fontstring);
465 /* Convert pipe write handle to a string and pass to child */
466 argv = sync_pipe_add_arg(argv, &argc, "-Z");
467 itoa(sync_pipe[WRITE], sync_pipe_fd, 10);
468 argv = sync_pipe_add_arg(argv, &argc, sync_pipe_fd);
470 /* Convert filter string to a quote delimited string and pass to child */
472 if (cfile.cfilter != NULL && strlen(cfile.cfilter) != 0) {
473 argv = sync_pipe_add_arg(argv, &argc, "-f");
474 filterstring = sync_pipe_quote_encapsulate(cfile.cfilter);
475 argv = sync_pipe_add_arg(argv, &argc, filterstring);
479 fork_child = spawnvp(_P_NOWAIT, ethereal_path, argv);
482 g_free(filterstring);
485 if (pipe(sync_pipe) < 0) {
486 /* Couldn't create the pipe between parent and child. */
488 unlink(cfile.save_file);
489 g_free(cfile.save_file);
490 cfile.save_file = NULL;
491 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK, "Couldn't create sync pipe: %s",
496 argv = sync_pipe_add_arg(argv, &argc, "-m");
497 argv = sync_pipe_add_arg(argv, &argc, prefs.PREFS_GUI_FONT_NAME);
499 if (cfile.cfilter != NULL && strlen(cfile.cfilter) != 0) {
500 argv = sync_pipe_add_arg(argv, &argc, "-f");
501 argv = sync_pipe_add_arg(argv, &argc, cfile.cfilter);
504 if ((fork_child = fork()) == 0) {
506 * Child process - run Ethereal with the right arguments to make
507 * it just pop up the live capture dialog box and capture with
508 * the specified capture parameters, writing to the specified file.
510 * args: -i interface specification
512 * -W file descriptor to write
513 * -c count to capture
516 * -f "filter expression"
519 dup(sync_pipe[WRITE]);
520 close(sync_pipe[READ]);
521 execvp(ethereal_path, argv);
522 snprintf(errmsg, sizeof errmsg, "Couldn't run %s in child process: %s",
523 ethereal_path, strerror(errno));
524 sync_pipe_errmsg_to_parent(errmsg);
526 /* Exit with "_exit()", so that we don't close the connection
527 to the X server (and cause stuff buffered up by our parent but
528 not yet sent to be sent, as that stuff should only be sent by
534 /* Parent process - read messages from the child process over the
536 g_free(argv); /* free up arg array */
538 /* Close the write side of the pipe, so that only the child has it
539 open, and thus it completely closes, and thus returns to us
540 an EOF indication, if the child closes it (either deliberately
541 or by exiting abnormally). */
542 close(sync_pipe[WRITE]);
544 /* Close the save file FD, as we won't be using it - we'll be opening
545 it and reading the save file through Wiretap. */
546 close(cfile.save_file_fd);
548 if (fork_child == -1) {
549 /* We couldn't even create the child process. */
551 close(sync_pipe[READ]);
552 unlink(cfile.save_file);
553 g_free(cfile.save_file);
554 cfile.save_file = NULL;
555 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK,
556 "Couldn't create child process: %s", strerror(error));
560 /* Read a byte count from "sync_pipe[READ]", terminated with a
561 colon; if the count is 0, the child process created the
562 capture file and we should start reading from it, otherwise
563 the capture couldn't start and the count is a count of bytes
564 of error message, and we should display the message. */
567 i = read(sync_pipe[READ], &c, 1);
569 /* EOF - the child process died.
570 Close the read side of the sync pipe, remove the capture file,
571 and report the failure. */
572 close(sync_pipe[READ]);
573 unlink(cfile.save_file);
574 g_free(cfile.save_file);
575 cfile.save_file = NULL;
576 sync_pipe_wait_for_child(TRUE);
579 if (c == SP_CAPSTART || c == SP_ERROR_MSG)
582 /* Child process handed us crap.
583 Close the read side of the sync pipe, remove the capture file,
584 and report the failure. */
585 close(sync_pipe[READ]);
586 unlink(cfile.save_file);
587 g_free(cfile.save_file);
588 cfile.save_file = NULL;
589 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK,
590 "Capture child process sent us a bad message");
593 byte_count = byte_count*10 + c - '0';
595 if (c != SP_CAPSTART) {
596 /* Failure - the child process sent us a message indicating
597 what the problem was. */
598 if (byte_count == 0) {
599 /* Zero-length message? */
600 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK,
601 "Capture child process failed, but its error message was empty.");
603 msg = g_malloc(byte_count + 1);
605 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK,
606 "Capture child process failed, but its error message was too big.");
608 i = read(sync_pipe[READ], msg, byte_count);
609 msg[byte_count] = '\0';
611 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK,
612 "Capture child process failed: Error %s reading its error message.",
615 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK,
616 "Capture child process failed: EOF reading its error message.");
617 sync_pipe_wait_for_child(FALSE);
619 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK, msg);
623 /* Close the sync pipe. */
624 close(sync_pipe[READ]);
626 /* Get rid of the save file - the capture never started. */
627 unlink(cfile.save_file);
628 g_free(cfile.save_file);
629 cfile.save_file = NULL;
634 /* The child process started a capture.
635 Attempt to open the capture file and set up to read it. */
636 err = cf_start_tail(cfile.save_file, is_tempfile, &cfile);
638 /* We weren't able to open the capture file; user has been
639 alerted. Close the sync pipe. */
641 close(sync_pipe[READ]);
643 /* Don't unlink the save file - leave it around, for debugging
645 g_free(cfile.save_file);
646 cfile.save_file = NULL;
649 /* We were able to open and set up to read the capture file;
650 arrange that our callback be called whenever it's possible
651 to read from the sync pipe, so that it's called when
652 the child process wants to tell us something. */
653 pipe_input_set_handler(sync_pipe[READ], (gpointer) &cfile, &fork_child, sync_pipe_input_cb);
659 /* There's stuff to read from the sync pipe, meaning the child has sent
660 us a message, or the sync pipe has closed, meaning the child has
661 closed it (perhaps because it exited). */
663 sync_pipe_input_cb(gint source, gpointer user_data)
665 capture_file *cf = (capture_file *)user_data;
667 char buffer[BUFSIZE+1], *p = buffer, *q = buffer, *msg, *r;
668 int nread, msglen, chars_to_copy;
673 if ((nread = read(source, buffer, BUFSIZE)) <= 0) {
674 /* The child has closed the sync pipe, meaning it's not going to be
675 capturing any more packets. Pick up its exit status, and
676 complain if it did anything other than exit with status 0. */
677 sync_pipe_wait_for_child(FALSE);
679 /* Read what remains of the capture file, and finish the capture.
680 XXX - do something if this fails? */
681 switch (cf_finish_tail(cf, &err)) {
685 simple_dialog(ESD_TYPE_INFO, ESD_BTN_OK,
686 "%sNo packets captured!%s\n\n"
687 "As no data was captured, closing the %scapture file!",
688 simple_dialog_primary_start(), simple_dialog_primary_end(),
689 (cf->is_tempfile) ? "temporary " : "");
694 /* Just because we got an error, that doesn't mean we were unable
695 to read any of the file; we handle what we could get from the
700 /* Exit by leaving the main loop, so that any quit functions
701 we registered get called. */
706 /* We're not doing a capture any more, so we don't have a save
708 g_free(cf->save_file);
709 cf->save_file = NULL;
714 buffer[nread] = '\0';
717 /* look for (possibly multiple) indications */
719 case SP_PACKET_COUNT :
726 cf->drops_known = TRUE;
738 /* Read the entire message.
739 XXX - if the child hasn't sent it all yet, this could cause us
740 to hang until they do. */
741 msg = g_malloc(msglen + 1);
743 while (msglen != 0) {
746 if ((nread = read(source, buffer, BUFSIZE)) <= 0)
751 chars_to_copy = MIN(msglen, nread);
752 memcpy(r, q, chars_to_copy);
755 nread -= chars_to_copy;
756 msglen -= chars_to_copy;
759 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK, msg);
769 /* Read from the capture file the number of records the child told us
771 XXX - do something if this fails? */
772 switch (cf_continue_tail(cf, to_read, &err)) {
776 /* Just because we got an error, that doesn't mean we were unable
777 to read any of the file; we handle what we could get from the
780 XXX - abort on a read error? */
784 /* Kill the child capture process; the user wants to exit, and we
785 shouldn't just leave it running. */
786 kill_capture_child();
794 sync_pipe_wait_for_child(gboolean always_report)
799 /* XXX - analyze the wait status and display more information
801 XXX - set "fork_child" to -1 if we find it exited? */
802 if (_cwait(&wstatus, fork_child, _WAIT_CHILD) == -1) {
803 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK,
804 "Child capture process stopped unexpectedly");
807 if (wait(&wstatus) != -1) {
808 if (WIFEXITED(wstatus)) {
809 /* The child exited; display its exit status, if it's not zero,
810 and even if it's zero if "always_report" is true. */
811 if (always_report || WEXITSTATUS(wstatus) != 0) {
812 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK,
813 "Child capture process exited: exit status %d",
814 WEXITSTATUS(wstatus));
816 } else if (WIFSTOPPED(wstatus)) {
817 /* It stopped, rather than exiting. "Should not happen." */
818 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK,
819 "Child capture process stopped: %s",
820 sync_pipe_signame(WSTOPSIG(wstatus)));
821 } else if (WIFSIGNALED(wstatus)) {
822 /* It died with a signal. */
823 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK,
824 "Child capture process died: %s%s",
825 sync_pipe_signame(WTERMSIG(wstatus)),
826 WCOREDUMP(wstatus) ? " - core dumped" : "");
828 /* What? It had to either have exited, or stopped, or died with
829 a signal; what happened here? */
830 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK,
831 "Child capture process died: wait status %#o", wstatus);
835 /* No more child process. */
841 sync_pipe_errmsg_to_parent(const char *errmsg)
843 int msglen = strlen(errmsg);
844 char lenbuf[SP_DECISIZE+1+1];
846 sprintf(lenbuf, "%u%c", msglen, SP_ERROR_MSG);
847 write(1, lenbuf, strlen(lenbuf));
848 write(1, errmsg, msglen);
852 sync_pipe_drops_to_parent(int drops)
854 char tmp[SP_DECISIZE+1+1];
855 sprintf(tmp, "%d%c", drops, SP_DROPS);
856 write(1, tmp, strlen(tmp));
860 sync_pipe_packet_count_to_parent(int packet_count)
862 char tmp[SP_DECISIZE+1+1];
863 sprintf(tmp, "%d%c", packet_count, SP_PACKET_COUNT);
864 write(1, tmp, strlen(tmp));
868 sync_pipe_capstart_to_parent(void)
870 static const char capstart_msg = SP_CAPSTART;
872 write(1, &capstart_msg, 1);
877 sync_pipe_signame(int sig)
880 static char sigmsg_buf[6+1+3+1];
889 sigmsg = "Interrupted";
897 sigmsg = "Illegal instruction";
901 sigmsg = "Trace trap";
909 sigmsg = "Arithmetic exception";
917 sigmsg = "Bus error";
921 sigmsg = "Segmentation violation";
924 /* http://metalab.unc.edu/pub/Linux/docs/HOWTO/GCC-HOWTO
925 Linux is POSIX compliant. These are not POSIX-defined signals ---
926 ISO/IEC 9945-1:1990 (IEEE Std 1003.1-1990), paragraph B.3.3.1.1 sez:
928 ``The signals SIGBUS, SIGEMT, SIGIOT, SIGTRAP, and SIGSYS
929 were omitted from POSIX.1 because their behavior is
930 implementation dependent and could not be adequately catego-
931 rized. Conforming implementations may deliver these sig-
932 nals, but must document the circumstances under which they
933 are delivered and note any restrictions concerning their
936 So we only check for SIGSYS on those systems that happen to
937 implement them (a system can be POSIX-compliant and implement
938 them, it's just that POSIX doesn't *require* a POSIX-compliant
939 system to implement them).
944 sigmsg = "Bad system call";
949 sigmsg = "Broken pipe";
953 sigmsg = "Alarm clock";
957 sigmsg = "Terminated";
961 sprintf(sigmsg_buf, "Signal %d", sig);
975 normal_do_capture(gboolean is_tempfile)
977 int capture_succeeded;
978 gboolean stats_known;
979 struct pcap_stat stats;
983 capture_succeeded = capture(&stats_known, &stats);
984 if (quit_after_cap) {
985 /* DON'T unlink the save file. Presumably someone wants it. */
988 if (!capture_succeeded) {
989 /* We didn't succeed in doing the capture, so we don't have a save
991 if (capture_opts.multi_files_on) {
994 g_free(cfile.save_file);
996 cfile.save_file = NULL;
999 /* Capture succeeded; attempt to read in the capture file. */
1000 if ((err = cf_open(cfile.save_file, is_tempfile, &cfile)) != 0) {
1001 /* We're not doing a capture any more, so we don't have a save
1003 if (capture_opts.multi_files_on) {
1006 g_free(cfile.save_file);
1008 cfile.save_file = NULL;
1012 /* Set the read filter to NULL. */
1013 cfile.rfcode = NULL;
1015 /* Get the packet-drop statistics.
1017 XXX - there are currently no packet-drop statistics stored
1018 in libpcap captures, and that's what we're reading.
1020 At some point, we will add support in Wiretap to return
1021 packet-drop statistics for capture file formats that store it,
1022 and will make "cf_read()" get those statistics from Wiretap.
1023 We clear the statistics (marking them as "not known") in
1024 "cf_open()", and "cf_read()" will only fetch them and mark
1025 them as known if Wiretap supplies them, so if we get the
1026 statistics now, after calling "cf_open()" but before calling
1027 "cf_read()", the values we store will be used by "cf_read()".
1029 If a future libpcap capture file format stores the statistics,
1030 we'll put them into the capture file that we write, and will
1031 thus not have to set them here - "cf_read()" will get them from
1032 the file and use them. */
1034 cfile.drops_known = TRUE;
1036 /* XXX - on some systems, libpcap doesn't bother filling in
1037 "ps_ifdrop" - it doesn't even set it to zero - so we don't
1038 bother looking at it.
1040 Ideally, libpcap would have an interface that gave us
1041 several statistics - perhaps including various interface
1042 error statistics - and would tell us which of them it
1043 supplies, allowing us to display only the ones it does. */
1044 cfile.drops = stats.ps_drop;
1046 switch (cf_read(&cfile)) {
1050 /* Just because we got an error, that doesn't mean we were unable
1051 to read any of the file; we handle what we could get from the
1056 /* Exit by leaving the main loop, so that any quit functions
1057 we registered get called. */
1058 main_window_nested_quit();
1062 /* We're not doing a capture any more, so we don't have a save
1064 if (capture_opts.multi_files_on) {
1067 g_free(cfile.save_file);
1069 cfile.save_file = NULL;
1071 /* if we didn't captured even a single packet, close the file again */
1072 if(cfile.count == 0) {
1073 simple_dialog(ESD_TYPE_INFO, ESD_BTN_OK,
1074 "%sNo packets captured!%s\n\n"
1075 "As no data was captured, closing the %scapture file!",
1076 simple_dialog_primary_start(), simple_dialog_primary_end(),
1077 (cfile.is_tempfile) ? "temporary " : "");
1084 * Timeout, in milliseconds, for reads from the stream of captured packets.
1086 #define CAP_READ_TIMEOUT 250
1089 /* Take care of byte order in the libpcap headers read from pipes.
1090 * (function taken from wiretap/libpcap.c) */
1092 cap_pipe_adjust_header(loop_data *ld, struct pcap_hdr *hdr, struct pcaprec_hdr *rechdr)
1094 if (ld->byte_swapped) {
1095 /* Byte-swap the record header fields. */
1096 rechdr->ts_sec = BSWAP32(rechdr->ts_sec);
1097 rechdr->ts_usec = BSWAP32(rechdr->ts_usec);
1098 rechdr->incl_len = BSWAP32(rechdr->incl_len);
1099 rechdr->orig_len = BSWAP32(rechdr->orig_len);
1102 /* In file format version 2.3, the "incl_len" and "orig_len" fields were
1103 swapped, in order to match the BPF header layout.
1105 Unfortunately, some files were, according to a comment in the "libpcap"
1106 source, written with version 2.3 in their headers but without the
1107 interchanged fields, so if "incl_len" is greater than "orig_len" - which
1108 would make no sense - we assume that we need to swap them. */
1109 if (hdr->version_major == 2 &&
1110 (hdr->version_minor < 3 ||
1111 (hdr->version_minor == 3 && rechdr->incl_len > rechdr->orig_len))) {
1114 temp = rechdr->orig_len;
1115 rechdr->orig_len = rechdr->incl_len;
1116 rechdr->incl_len = temp;
1120 /* Mimic pcap_open_live() for pipe captures
1121 * We check if "pipename" is "-" (stdin) or a FIFO, open it, and read the
1123 * N.B. : we can't read the libpcap formats used in RedHat 6.1 or SuSE 6.3
1124 * because we can't seek on pipes (see wiretap/libpcap.c for details) */
1126 cap_pipe_open_live(char *pipename, struct pcap_hdr *hdr, loop_data *ld,
1127 char *errmsg, int errmsgl)
1129 struct stat pipe_stat;
1133 unsigned int bytes_read;
1135 struct timeval timeout;
1138 * XXX Ethereal blocks until we return
1140 if (strcmp(pipename, "-") == 0)
1141 fd = 0; /* read from stdin */
1143 if (stat(pipename, &pipe_stat) < 0) {
1144 if (errno == ENOENT || errno == ENOTDIR)
1145 ld->cap_pipe_err = PIPNEXIST;
1147 snprintf(errmsg, errmsgl,
1148 "The capture session could not be initiated "
1149 "due to error on pipe: %s", strerror(errno));
1150 ld->cap_pipe_err = PIPERR;
1154 if (! S_ISFIFO(pipe_stat.st_mode)) {
1155 if (S_ISCHR(pipe_stat.st_mode)) {
1157 * Assume the user specified an interface on a system where
1158 * interfaces are in /dev. Pretend we haven't seen it.
1160 ld->cap_pipe_err = PIPNEXIST;
1162 snprintf(errmsg, errmsgl,
1163 "The capture session could not be initiated because\n"
1164 "\"%s\" is neither an interface nor a pipe", pipename);
1165 ld->cap_pipe_err = PIPERR;
1169 fd = open(pipename, O_RDONLY | O_NONBLOCK);
1171 snprintf(errmsg, errmsgl,
1172 "The capture session could not be initiated "
1173 "due to error on pipe open: %s", strerror(errno));
1174 ld->cap_pipe_err = PIPERR;
1179 ld->from_cap_pipe = TRUE;
1181 /* read the pcap header */
1184 while (bytes_read < sizeof magic) {
1187 timeout.tv_usec = CAP_READ_TIMEOUT*1000;
1188 sel_ret = select(fd+1, &rfds, NULL, NULL, &timeout);
1190 snprintf(errmsg, errmsgl,
1191 "Unexpected error from select: %s", strerror(errno));
1193 } else if (sel_ret > 0) {
1194 b = read(fd, ((char *)&magic)+bytes_read, sizeof magic-bytes_read);
1197 snprintf(errmsg, errmsgl, "End of file on pipe during open");
1199 snprintf(errmsg, errmsgl, "Error on pipe during open: %s",
1209 /* Host that wrote it has our byte order, and was running
1210 a program using either standard or ss990417 libpcap. */
1211 ld->byte_swapped = FALSE;
1212 ld->modified = FALSE;
1214 case PCAP_MODIFIED_MAGIC:
1215 /* Host that wrote it has our byte order, but was running
1216 a program using either ss990915 or ss991029 libpcap. */
1217 ld->byte_swapped = FALSE;
1218 ld->modified = TRUE;
1220 case PCAP_SWAPPED_MAGIC:
1221 /* Host that wrote it has a byte order opposite to ours,
1222 and was running a program using either standard or
1223 ss990417 libpcap. */
1224 ld->byte_swapped = TRUE;
1225 ld->modified = FALSE;
1227 case PCAP_SWAPPED_MODIFIED_MAGIC:
1228 /* Host that wrote it out has a byte order opposite to
1229 ours, and was running a program using either ss990915
1230 or ss991029 libpcap. */
1231 ld->byte_swapped = TRUE;
1232 ld->modified = TRUE;
1235 /* Not a "libpcap" type we know about. */
1236 snprintf(errmsg, errmsgl, "Unrecognized libpcap format");
1240 /* Read the rest of the header */
1242 while (bytes_read < sizeof(struct pcap_hdr)) {
1245 timeout.tv_usec = CAP_READ_TIMEOUT*1000;
1246 sel_ret = select(fd+1, &rfds, NULL, NULL, &timeout);
1248 snprintf(errmsg, errmsgl,
1249 "Unexpected error from select: %s", strerror(errno));
1251 } else if (sel_ret > 0) {
1252 b = read(fd, ((char *)hdr)+bytes_read,
1253 sizeof(struct pcap_hdr) - bytes_read);
1256 snprintf(errmsg, errmsgl, "End of file on pipe during open");
1258 snprintf(errmsg, errmsgl, "Error on pipe during open: %s",
1266 if (ld->byte_swapped) {
1267 /* Byte-swap the header fields about which we care. */
1268 hdr->version_major = BSWAP16(hdr->version_major);
1269 hdr->version_minor = BSWAP16(hdr->version_minor);
1270 hdr->snaplen = BSWAP32(hdr->snaplen);
1271 hdr->network = BSWAP32(hdr->network);
1274 if (hdr->version_major < 2) {
1275 snprintf(errmsg, errmsgl, "Unable to read old libpcap format");
1279 ld->cap_pipe_state = STATE_EXPECT_REC_HDR;
1280 ld->cap_pipe_err = PIPOK;
1284 ld->cap_pipe_err = PIPERR;
1290 /* We read one record from the pipe, take care of byte order in the record
1291 * header, write the record in the capture file, and update capture statistics. */
1294 cap_pipe_dispatch(int fd, loop_data *ld, struct pcap_hdr *hdr,
1295 struct pcaprec_modified_hdr *rechdr, guchar *data,
1296 char *errmsg, int errmsgl)
1298 struct pcap_pkthdr phdr;
1300 enum { PD_REC_HDR_READ, PD_DATA_READ, PD_PIPE_EOF, PD_PIPE_ERR,
1303 switch (ld->cap_pipe_state) {
1305 case STATE_EXPECT_REC_HDR:
1306 ld->bytes_to_read = ld->modified ?
1307 sizeof(struct pcaprec_modified_hdr) : sizeof(struct pcaprec_hdr);
1309 ld->cap_pipe_state = STATE_READ_REC_HDR;
1312 case STATE_READ_REC_HDR:
1313 b = read(fd, ((char *)rechdr)+ld->bytes_read,
1314 ld->bytes_to_read - ld->bytes_read);
1317 result = PD_PIPE_EOF;
1319 result = PD_PIPE_ERR;
1322 if ((ld->bytes_read += b) < ld->bytes_to_read)
1324 result = PD_REC_HDR_READ;
1327 case STATE_EXPECT_DATA:
1329 ld->cap_pipe_state = STATE_READ_DATA;
1332 case STATE_READ_DATA:
1333 b = read(fd, data+ld->bytes_read, rechdr->hdr.incl_len - ld->bytes_read);
1336 result = PD_PIPE_EOF;
1338 result = PD_PIPE_ERR;
1341 if ((ld->bytes_read += b) < rechdr->hdr.incl_len)
1343 result = PD_DATA_READ;
1347 snprintf(errmsg, errmsgl, "cap_pipe_dispatch: invalid state");
1350 } /* switch (ld->cap_pipe_state) */
1353 * We've now read as much data as we were expecting, so process it.
1357 case PD_REC_HDR_READ:
1358 /* We've read the header. Take care of byte order. */
1359 cap_pipe_adjust_header(ld, hdr, &rechdr->hdr);
1360 if (rechdr->hdr.incl_len > WTAP_MAX_PACKET_SIZE) {
1361 snprintf(errmsg, errmsgl, "Frame %u too long (%d bytes)",
1362 ld->counts.total+1, rechdr->hdr.incl_len);
1365 ld->cap_pipe_state = STATE_EXPECT_DATA;
1369 /* Fill in a "struct pcap_pkthdr", and process the packet. */
1370 phdr.ts.tv_sec = rechdr->hdr.ts_sec;
1371 phdr.ts.tv_usec = rechdr->hdr.ts_usec;
1372 phdr.caplen = rechdr->hdr.incl_len;
1373 phdr.len = rechdr->hdr.orig_len;
1375 capture_pcap_cb((guchar *)ld, &phdr, data);
1377 ld->cap_pipe_state = STATE_EXPECT_REC_HDR;
1381 ld->cap_pipe_err = PIPEOF;
1385 snprintf(errmsg, errmsgl, "Error reading from pipe: %s",
1392 ld->cap_pipe_err = PIPERR;
1393 /* Return here rather than inside the switch to prevent GCC warning */
1396 #endif /* not _WIN32 */
1399 * This needs to be static, so that the SIGUSR1 handler can clear the "go"
1402 static loop_data ld;
1404 /* Do the low-level work of a capture.
1405 Returns TRUE if it succeeds, FALSE otherwise. */
1407 capture(gboolean *stats_known, struct pcap_stat *stats)
1412 gchar open_err_str[PCAP_ERRBUF_SIZE];
1413 gchar lookup_net_err_str[PCAP_ERRBUF_SIZE];
1414 bpf_u_int32 netnum, netmask;
1415 struct bpf_program fcode;
1416 const char *set_linktype_err_str;
1417 time_t upd_time, cur_time;
1420 condition *cnd_file_duration = NULL;
1421 condition *cnd_autostop_files = NULL;
1422 condition *cnd_autostop_size = NULL;
1423 condition *cnd_autostop_duration = NULL;
1424 guint32 autostop_files = 0;
1425 char errmsg[4096+1];
1428 capture_info capture_ui;
1431 WORD wVersionRequested;
1435 struct timeval timeout;
1436 static const char ppamsg[] = "can't find PPA for ";
1440 struct pcap_hdr hdr;
1441 struct pcaprec_modified_hdr rechdr;
1442 guchar pcap_data[WTAP_MAX_PACKET_SIZE];
1444 #ifdef MUST_DO_SELECT
1447 gboolean show_info = capture_opts.show_info || !capture_opts.sync_mode;
1449 /* Initialize Windows Socket if we are in a WIN32 OS
1450 This needs to be done before querying the interface for network/netmask */
1452 /* XXX - do we really require 1.1 or earlier?
1453 Are there any versions that support only 2.0 or higher? */
1454 wVersionRequested = MAKEWORD(1, 1);
1455 err = WSAStartup(wVersionRequested, &wsaData);
1459 case WSASYSNOTREADY:
1460 snprintf(errmsg, sizeof errmsg,
1461 "Couldn't initialize Windows Sockets: Network system not ready for network communication");
1464 case WSAVERNOTSUPPORTED:
1465 snprintf(errmsg, sizeof errmsg,
1466 "Couldn't initialize Windows Sockets: Windows Sockets version %u.%u not supported",
1467 LOBYTE(wVersionRequested), HIBYTE(wVersionRequested));
1470 case WSAEINPROGRESS:
1471 snprintf(errmsg, sizeof errmsg,
1472 "Couldn't initialize Windows Sockets: Blocking operation is in progress");
1476 snprintf(errmsg, sizeof errmsg,
1477 "Couldn't initialize Windows Sockets: Limit on the number of tasks supported by this WinSock implementation has been reached");
1481 snprintf(errmsg, sizeof errmsg,
1482 "Couldn't initialize Windows Sockets: Bad pointer passed to WSAStartup");
1486 snprintf(errmsg, sizeof errmsg,
1487 "Couldn't initialize Windows Sockets: error %d", err);
1496 ld.counts.total = 0;
1497 if (capture_opts.has_autostop_packets)
1498 ld.max = capture_opts.autostop_packets;
1500 ld.max = 0; /* no limit */
1501 ld.err = 0; /* no error seen yet */
1502 ld.linktype = WTAP_ENCAP_UNKNOWN;
1503 ld.pcap_err = FALSE;
1504 ld.from_cap_pipe = FALSE;
1505 ld.sync_packets = 0;
1513 ld.counts.netbios = 0;
1514 ld.counts.vines = 0;
1515 ld.counts.other = 0;
1519 /* We haven't yet gotten the capture statistics. */
1520 *stats_known = FALSE;
1522 /* Open the network interface to capture from it.
1523 Some versions of libpcap may put warnings into the error buffer
1524 if they succeed; to tell if that's happened, we have to clear
1525 the error buffer, and check if it's still a null string. */
1526 open_err_str[0] = '\0';
1527 pch = pcap_open_live(cfile.iface,
1528 capture_opts.has_snaplen ? capture_opts.snaplen :
1529 WTAP_MAX_PACKET_SIZE,
1530 capture_opts.promisc_mode, CAP_READ_TIMEOUT,
1535 /* try to set the capture buffer size */
1536 if (pcap_setbuff(pch, capture_opts.buffer_size * 1024 * 1024) != 0) {
1537 simple_dialog(ESD_TYPE_INFO, ESD_BTN_OK,
1538 "%sCouldn't set the capture buffer size!%s\n"
1540 "The capture buffer size of %luMB seems to be too high for your machine,\n"
1541 "the default of 1MB will be used.\n"
1543 "Nonetheless, the capture is started.\n",
1544 simple_dialog_primary_start(), simple_dialog_primary_end(), capture_opts.buffer_size);
1548 /* setting the data link type only works on real interfaces */
1549 if (capture_opts.linktype != -1) {
1550 set_linktype_err_str = set_pcap_linktype(pch, cfile.iface,
1551 capture_opts.linktype);
1552 if (set_linktype_err_str != NULL) {
1553 snprintf(errmsg, sizeof errmsg, "Unable to set data link type (%s).",
1554 set_linktype_err_str);
1559 /* We couldn't open "cfile.iface" as a network device. */
1561 /* On Windows, we don't support capturing on pipes, so we give up.
1562 If this is a child process that does the capturing in sync
1563 mode or fork mode, it shouldn't do any UI stuff until we pop up the
1564 capture-progress window, and, since we couldn't start the
1565 capture, we haven't popped it up. */
1566 if (!capture_child) {
1567 main_window_update();
1570 /* On Win32 OSes, the capture devices are probably available to all
1571 users; don't warn about permissions problems.
1573 Do, however, warn that WAN devices aren't supported. */
1574 snprintf(errmsg, sizeof errmsg,
1575 "The capture session could not be initiated (%s).\n"
1576 "Please check that you have the proper interface specified.\n"
1578 "Note that the WinPcap 2.x version of the driver Ethereal uses for packet\n"
1579 "capture on Windows doesn't support capturing on PPP/WAN interfaces in\n"
1580 "Windows NT/2000/XP/2003 Server, and that the WinPcap 3.0 and later versions\n"
1581 "don't support capturing on PPP/WAN interfaces at all.",
1585 /* try to open cfile.iface as a pipe */
1586 pipe_fd = cap_pipe_open_live(cfile.iface, &hdr, &ld, errmsg, sizeof errmsg);
1588 if (pipe_fd == -1) {
1590 /* If this is a child process that does the capturing in sync
1591 * mode or fork mode, it shouldn't do any UI stuff until we pop up the
1592 * capture-progress window, and, since we couldn't start the
1593 * capture, we haven't popped it up.
1595 if (!capture_child) {
1596 main_window_update();
1599 if (ld.cap_pipe_err == PIPNEXIST) {
1600 /* Pipe doesn't exist, so output message for interface */
1602 /* If we got a "can't find PPA for XXX" message, warn the user (who
1603 is running Ethereal on HP-UX) that they don't have a version
1604 of libpcap that properly handles HP-UX (libpcap 0.6.x and later
1605 versions, which properly handle HP-UX, say "can't find /dev/dlpi
1606 PPA for XXX" rather than "can't find PPA for XXX"). */
1607 if (strncmp(open_err_str, ppamsg, sizeof ppamsg - 1) == 0)
1610 "You are running Ethereal with a version of the libpcap library\n"
1611 "that doesn't handle HP-UX network devices well; this means that\n"
1612 "Ethereal may not be able to capture packets.\n"
1614 "To fix this, you should install libpcap 0.6.2, or a later version\n"
1615 "of libpcap, rather than libpcap 0.4 or 0.5.x. It is available in\n"
1616 "packaged binary form from the Software Porting And Archive Centre\n"
1617 "for HP-UX; the Centre is at http://hpux.connect.org.uk/ - the page\n"
1618 "at the URL lists a number of mirror sites.";
1621 snprintf(errmsg, sizeof errmsg,
1622 "The capture session could not be initiated (%s).\n"
1623 "Please check to make sure you have sufficient permissions, and that\n"
1624 "you have the proper interface or pipe specified.%s", open_err_str,
1628 * Else pipe (or file) does exist and cap_pipe_open_live() has
1633 /* cap_pipe_open_live() succeeded; don't want
1634 error message from pcap_open_live() */
1635 open_err_str[0] = '\0';
1639 /* capture filters only work on real interfaces */
1640 if (cfile.cfilter && !ld.from_cap_pipe) {
1641 /* A capture filter was specified; set it up. */
1642 if (pcap_lookupnet(cfile.iface, &netnum, &netmask, lookup_net_err_str) < 0) {
1644 * Well, we can't get the netmask for this interface; it's used
1645 * only for filters that check for broadcast IP addresses, so
1646 * we just punt and use 0. It might be nice to warn the user,
1647 * but that's a pain in a GUI application, as it'd involve popping
1648 * up a message box, and it's not clear how often this would make
1649 * a difference (only filters that check for IP broadcast addresses
1654 if (pcap_compile(pch, &fcode, cfile.cfilter, 1, netmask) < 0) {
1655 dfilter_t *rfcode = NULL;
1656 /* filter string invalid, did the user tried a display filter? */
1657 if (dfilter_compile(cfile.cfilter, &rfcode) && rfcode != NULL) {
1658 snprintf(errmsg, sizeof errmsg,
1659 "%sInvalid capture filter: \"%s\"!%s\n"
1661 "That string looks like a valid display filter; however, it is not a valid\n"
1662 "capture filter (%s).\n"
1664 "Note that display filters and capture filters don't have the same syntax,\n"
1665 "so you can't use most display filter expressions as capture filters.\n"
1667 "See the help for a description of the capture filter syntax.",
1668 simple_dialog_primary_start(), cfile.cfilter, simple_dialog_primary_end(),
1670 dfilter_free(rfcode);
1672 snprintf(errmsg, sizeof errmsg,
1673 "%sInvalid capture filter: \"%s\"!%s\n"
1675 "That string is not a valid capture filter (%s).\n"
1676 "See the help for a description of the capture filter syntax.",
1677 simple_dialog_primary_start(), cfile.cfilter, simple_dialog_primary_end(),
1682 if (pcap_setfilter(pch, &fcode) < 0) {
1683 snprintf(errmsg, sizeof errmsg, "Can't install filter (%s).",
1689 /* Set up to write to the capture file. */
1691 if (ld.from_cap_pipe) {
1692 pcap_encap = hdr.network;
1693 file_snaplen = hdr.snaplen;
1697 pcap_encap = get_pcap_linktype(pch, cfile.iface);
1698 file_snaplen = pcap_snapshot(pch);
1700 ld.linktype = wtap_pcap_encap_to_wtap_encap(pcap_encap);
1701 if (ld.linktype == WTAP_ENCAP_UNKNOWN) {
1702 snprintf(errmsg, sizeof errmsg,
1703 "The network you're capturing from is of a type"
1704 " that Ethereal doesn't support (data link type %d).", pcap_encap);
1707 if (capture_opts.multi_files_on) {
1708 ld.pdh = ringbuf_init_wtap_dump_fdopen(WTAP_FILE_PCAP, ld.linktype,
1709 file_snaplen, &err);
1711 ld.pdh = wtap_dump_fdopen(cfile.save_file_fd, WTAP_FILE_PCAP,
1712 ld.linktype, file_snaplen, &err);
1715 if (ld.pdh == NULL) {
1716 /* We couldn't set up to write to the capture file. */
1719 case WTAP_ERR_CANT_OPEN:
1720 strcpy(errmsg, "The file to which the capture would be saved"
1721 " couldn't be created for some unknown reason.");
1724 case WTAP_ERR_SHORT_WRITE:
1725 strcpy(errmsg, "A full header couldn't be written to the file"
1726 " to which the capture would be saved.");
1731 snprintf(errmsg, sizeof(errmsg),
1732 "The file to which the capture would be"
1733 " saved (\"%s\") could not be opened: Error %d.",
1734 cfile.save_file, err);
1736 snprintf(errmsg, sizeof(errmsg),
1737 "The file to which the capture would be"
1738 " saved (\"%s\") could not be opened: %s.",
1739 cfile.save_file, strerror(err));
1746 /* Does "open_err_str" contain a non-empty string? If so, "pcap_open_live()"
1747 returned a warning; print it, but keep capturing. */
1748 if (open_err_str[0] != '\0')
1749 g_warning("%s.", open_err_str);
1751 /* XXX - capture SIGTERM and close the capture, in case we're on a
1752 Linux 2.0[.x] system and you have to explicitly close the capture
1753 stream in order to turn promiscuous mode off? We need to do that
1754 in other places as well - and I don't think that works all the
1755 time in any case, due to libpcap bugs. */
1757 if (capture_child) {
1758 /* Well, we should be able to start capturing.
1760 This is the child process for a sync mode capture, so sync out
1761 the capture file, so the header makes it to the file system,
1762 and send a "capture started successfully and capture file created"
1763 message to our parent so that they'll open the capture file and
1764 update its windows to indicate that we have a live capture in
1766 fflush(wtap_dump_file(ld.pdh));
1767 sync_pipe_capstart_to_parent();
1770 /* start capture info dialog */
1772 capture_ui.callback_data = &ld;
1773 capture_ui.counts = &ld.counts;
1774 capture_info_create(&capture_ui, cfile.iface);
1777 start_time = time(NULL);
1778 upd_time = time(NULL);
1779 #ifdef MUST_DO_SELECT
1780 if (!ld.from_cap_pipe) pcap_fd = pcap_fileno(pch);
1785 * Catch SIGUSR1, so that we exit cleanly if the parent process
1786 * kills us with it due to the user selecting "Capture->Stop".
1789 signal(SIGUSR1, stop_capture_signal_handler);
1792 /* initialize capture stop conditions */
1793 init_capture_stop_conditions();
1794 /* create stop conditions */
1795 if (capture_opts.has_autostop_filesize)
1797 cnd_new(CND_CLASS_CAPTURESIZE,(long)capture_opts.autostop_filesize);
1798 if (capture_opts.has_autostop_duration)
1799 cnd_autostop_duration =
1800 cnd_new(CND_CLASS_TIMEOUT,(gint32)capture_opts.autostop_duration);
1802 if (capture_opts.multi_files_on) {
1803 if (capture_opts.has_file_duration)
1805 cnd_new(CND_CLASS_TIMEOUT, capture_opts.file_duration);
1807 if (capture_opts.has_autostop_files)
1808 cnd_autostop_files =
1809 cnd_new(CND_CLASS_CAPTURESIZE, capture_opts.autostop_files);
1812 /* WOW, everything is prepared! */
1813 /* please fasten your seat belts, we will enter now the actual capture loop */
1815 main_window_update();
1818 if (ld.from_cap_pipe) {
1820 FD_SET(pipe_fd, &set1);
1822 timeout.tv_usec = CAP_READ_TIMEOUT*1000;
1823 sel_ret = select(pipe_fd+1, &set1, NULL, NULL, &timeout);
1826 if (sel_ret < 0 && errno != EINTR) {
1827 snprintf(errmsg, sizeof(errmsg),
1828 "Unexpected error from select: %s", strerror(errno));
1829 popup_errmsg(errmsg);
1834 * "select()" says we can read from the pipe without blocking
1836 inpkts = cap_pipe_dispatch(pipe_fd, &ld, &hdr, &rechdr, pcap_data,
1837 errmsg, sizeof errmsg);
1846 #ifdef MUST_DO_SELECT
1848 * Sigh. The semantics of the read timeout argument to
1849 * "pcap_open_live()" aren't particularly well specified by
1850 * the "pcap" man page - at least with the BSD BPF code, the
1851 * intent appears to be, at least in part, a way of cutting
1852 * down the number of reads done on a capture, by blocking
1853 * until the buffer fills or a timer expires - and the Linux
1854 * libpcap doesn't actually support it, so we can't use it
1855 * to break out of the "pcap_dispatch()" every 1/4 of a second
1856 * or so. Linux's libpcap is not the only libpcap that doesn't
1857 * support the read timeout.
1859 * Furthermore, at least on Solaris, the bufmod STREAMS module's
1860 * read timeout won't go off if no data has arrived, i.e. it cannot
1861 * be used to guarantee that a read from a DLPI stream will return
1862 * within a specified amount of time regardless of whether any
1863 * data arrives or not.
1865 * Thus, on all platforms other than BSD, we do a "select()" on the
1866 * file descriptor for the capture, with a timeout of CAP_READ_TIMEOUT
1867 * milliseconds, or CAP_READ_TIMEOUT*1000 microseconds.
1869 * "select()", on BPF devices, doesn't work as you might expect;
1870 * at least on some versions of some flavors of BSD, the timer
1871 * doesn't start until a read is done, so it won't expire if
1872 * only a "select()" or "poll()" is posted.
1875 FD_SET(pcap_fd, &set1);
1877 timeout.tv_usec = CAP_READ_TIMEOUT*1000;
1878 sel_ret = select(pcap_fd+1, &set1, NULL, NULL, &timeout);
1881 * "select()" says we can read from it without blocking; go for
1884 inpkts = pcap_dispatch(pch, 1, capture_pcap_cb, (guchar *) &ld);
1891 if (sel_ret < 0 && errno != EINTR) {
1892 snprintf(errmsg, sizeof(errmsg),
1893 "Unexpected error from select: %s", strerror(errno));
1894 popup_errmsg(errmsg);
1899 inpkts = pcap_dispatch(pch, 1, capture_pcap_cb, (guchar *) &ld);
1904 #endif /* MUST_DO_SELECT */
1908 ld.sync_packets += inpkts;
1910 /* check capture size condition */
1911 if (cnd_autostop_size != NULL && cnd_eval(cnd_autostop_size,
1912 (guint32)wtap_get_bytes_dumped(ld.pdh))){
1913 /* Capture size limit reached, do we have another file? */
1914 if (capture_opts.multi_files_on) {
1915 if (cnd_autostop_files != NULL && cnd_eval(cnd_autostop_files, ++autostop_files)) {
1916 /* no files left: stop here */
1921 /* Switch to the next ringbuffer file */
1922 if (ringbuf_switch_file(&cfile, &ld.pdh, &ld.err)) {
1923 /* File switch succeeded: reset the conditions */
1924 cnd_reset(cnd_autostop_size);
1925 if (cnd_file_duration) {
1926 cnd_reset(cnd_file_duration);
1929 /* File switch failed: stop here */
1934 /* single file, stop now */
1938 } /* cnd_autostop_size */
1941 /* Only update once a second so as not to overload slow displays */
1942 cur_time = time(NULL);
1943 if (cur_time > upd_time) {
1944 upd_time = cur_time;
1946 /*if (pcap_stats(pch, stats) >= 0) {
1947 *stats_known = TRUE;
1950 /* Let the parent process know. */
1951 /* calculate and display running time */
1953 cur_time -= start_time;
1954 capture_ui.running_time = cur_time;
1955 capture_ui.new_packets = ld.sync_packets;
1956 capture_info_update(&capture_ui);
1959 if (ld.sync_packets) {
1961 fflush(wtap_dump_file(ld.pdh));
1963 if (capture_child) {
1964 /* This is the child process for a sync mode capture, so send
1965 our parent a message saying we've written out "ld.sync_packets"
1966 packets to the capture file. */
1967 sync_pipe_packet_count_to_parent(ld.sync_packets);
1970 ld.sync_packets = 0;
1973 /* check capture duration condition */
1974 if (cnd_autostop_duration != NULL && cnd_eval(cnd_autostop_duration)) {
1975 /* The maximum capture time has elapsed; stop the capture. */
1980 /* check capture file duration condition */
1981 if (cnd_file_duration != NULL && cnd_eval(cnd_file_duration)) {
1982 /* duration limit reached, do we have another file? */
1983 if (capture_opts.multi_files_on) {
1984 if (cnd_autostop_files != NULL && cnd_eval(cnd_autostop_files, ++autostop_files)) {
1985 /* no files left: stop here */
1990 /* Switch to the next ringbuffer file */
1991 if (ringbuf_switch_file(&cfile, &ld.pdh, &ld.err)) {
1992 /* file switch succeeded: reset the conditions */
1993 cnd_reset(cnd_file_duration);
1994 if(cnd_autostop_size)
1995 cnd_reset(cnd_autostop_size);
1997 /* File switch failed: stop here */
2002 /* single file, stop now */
2006 } /* cnd_file_duration */
2009 } /* while (ld.go) */
2011 /* delete stop conditions */
2012 if (cnd_file_duration != NULL)
2013 cnd_delete(cnd_file_duration);
2014 if (cnd_autostop_files != NULL)
2015 cnd_delete(cnd_autostop_files);
2016 if (cnd_autostop_size != NULL)
2017 cnd_delete(cnd_autostop_size);
2018 if (cnd_autostop_duration != NULL)
2019 cnd_delete(cnd_autostop_duration);
2022 snprintf(errmsg, sizeof(errmsg), "Error while capturing packets: %s",
2024 popup_errmsg(errmsg);
2028 } else if (ld.from_cap_pipe && ld.cap_pipe_err == PIPERR)
2029 popup_errmsg(errmsg);
2035 get_capture_file_io_error(errmsg, sizeof(errmsg), cfile.save_file, ld.err,
2037 popup_errmsg(errmsg);
2041 if (capture_opts.multi_files_on) {
2042 close_ok = ringbuf_wtap_dump_close(&cfile, &err);
2044 close_ok = wtap_dump_close(ld.pdh, &err);
2046 /* If we've displayed a message about a write error, there's no point
2047 in displaying another message about an error on close. */
2048 if (!close_ok && write_ok) {
2049 get_capture_file_io_error(errmsg, sizeof(errmsg), cfile.save_file, err,
2051 popup_errmsg(errmsg);
2053 /* Set write_ok to mean the write and the close were successful. */
2054 write_ok = (write_ok && close_ok);
2058 * XXX We exhibit different behaviour between normal mode and sync mode
2059 * when the pipe is stdin and not already at EOF. If we're a child, the
2060 * parent's stdin isn't closed, so if the user starts another capture,
2061 * cap_pipe_open_live() will very likely not see the expected magic bytes and
2062 * will say "Unrecognized libpcap format". On the other hand, in normal
2063 * mode, cap_pipe_open_live() will say "End of file on pipe during open".
2065 if (ld.from_cap_pipe && pipe_fd >= 0)
2070 /* Get the capture statistics, so we know how many packets were
2072 if (pcap_stats(pch, stats) >= 0) {
2073 *stats_known = TRUE;
2074 if (capture_child) {
2075 /* Let the parent process know. */
2076 sync_pipe_drops_to_parent(stats->ps_drop);
2079 snprintf(errmsg, sizeof(errmsg),
2080 "Can't get packet-drop statistics: %s",
2082 popup_errmsg(errmsg);
2088 /* Shut down windows sockets */
2093 capture_info_destroy(&capture_ui);
2099 if (capture_opts.multi_files_on) {
2100 /* cleanup ringbuffer */
2101 ringbuf_error_cleanup();
2103 /* We can't use the save file, and we have no wtap_dump stream
2104 to close in order to close it, so close the FD directly. */
2105 close(cfile.save_file_fd);
2107 /* We couldn't even start the capture, so get rid of the capture
2109 unlink(cfile.save_file); /* silently ignore error */
2110 g_free(cfile.save_file);
2112 cfile.save_file = NULL;
2113 popup_errmsg(errmsg);
2116 if (ld.from_cap_pipe) {
2130 get_capture_file_io_error(char *errmsg, int errmsglen, const char *fname,
2131 int err, gboolean is_close)
2136 snprintf(errmsg, errmsglen,
2137 "Not all the packets could be written to the file"
2138 " to which the capture was being saved\n"
2139 "(\"%s\") because there is no space left on the file system\n"
2140 "on which that file resides.",
2146 snprintf(errmsg, errmsglen,
2147 "Not all the packets could be written to the file"
2148 " to which the capture was being saved\n"
2149 "(\"%s\") because you are too close to, or over,"
2150 " your disk quota\n"
2151 "on the file system on which that file resides.",
2156 case WTAP_ERR_CANT_CLOSE:
2157 snprintf(errmsg, errmsglen,
2158 "The file to which the capture was being saved"
2159 " couldn't be closed for some unknown reason.");
2162 case WTAP_ERR_SHORT_WRITE:
2163 snprintf(errmsg, errmsglen,
2164 "Not all the packets could be written to the file"
2165 " to which the capture was being saved\n"
2172 snprintf(errmsg, errmsglen,
2173 "The file to which the capture was being saved\n"
2174 "(\"%s\") could not be closed: %s.",
2175 fname, wtap_strerror(err));
2177 snprintf(errmsg, errmsglen,
2178 "An error occurred while writing to the file"
2179 " to which the capture was being saved\n"
2181 fname, wtap_strerror(err));
2188 popup_errmsg(const char *errmsg)
2190 if (capture_child) {
2191 /* This is the child process for a sync mode capture.
2192 Send the error message to our parent, so they can display a
2193 dialog box containing it. */
2194 sync_pipe_errmsg_to_parent(errmsg);
2196 /* Display the dialog box ourselves; there's no parent. */
2197 simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK, "%s", errmsg);
2202 stop_capture_signal_handler(int signo _U_)
2211 if (fork_child != -1) {
2213 kill(fork_child, SIGUSR1);
2215 /* XXX: this is not the preferred method of closing a process!
2216 * the clean way would be getting the process id of the child process,
2217 * then getting window handle hWnd of that process (using EnumChildWindows),
2218 * and then do a SendMessage(hWnd, WM_CLOSE, 0, 0)
2220 * Unfortunately, I don't know how to get the process id from the handle */
2221 /* Hint: OpenProcess will get an handle from the id, not vice versa :-(
2223 * Hint: GenerateConsoleCtrlEvent() will only work, if both processes are
2224 * running in the same console, I don't know if that is true for our case.
2225 * And this also will require to have the process id
2227 TerminateProcess((HANDLE) fork_child, 0);
2235 kill_capture_child(void)
2237 if (fork_child != -1)
2239 kill(fork_child, SIGTERM); /* SIGTERM so it can clean up if necessary */
2241 /* XXX: this is not the preferred method of closing a process!
2242 * the clean way would be getting the process id of the child process,
2243 * then getting window handle hWnd of that process (using EnumChildWindows),
2244 * and then do a SendMessage(hWnd, WM_CLOSE, 0, 0)
2246 * Unfortunately, I don't know how to get the process id from the handle */
2247 /* Hint: OpenProcess will get an handle from the id, not vice versa :-(
2249 * Hint: GenerateConsoleCtrlEvent() will only work, if both processes are
2250 * running in the same console, I don't know if that is true for our case.
2251 * And this also will require to have the process id
2253 TerminateProcess((HANDLE) fork_child, 0);
2257 /* one packet was captured, process it */
2259 capture_pcap_cb(guchar *user, const struct pcap_pkthdr *phdr,
2262 struct wtap_pkthdr whdr;
2263 union wtap_pseudo_header pseudo_header;
2264 loop_data *ld = (loop_data *) user;
2267 /* user told us to stop after x packets, do we have enough? */
2268 if ((++ld->counts.total >= ld->max) && (ld->max > 0))
2273 /* Convert from libpcap to Wiretap format.
2274 If that fails, set "ld->go" to FALSE, to stop the capture, and set
2275 "ld->err" to the error. */
2276 pd = wtap_process_pcap_packet(ld->linktype, phdr, pd, &pseudo_header,
2285 /* We're supposed to write the packet to a file; do so.
2286 If this fails, set "ld->go" to FALSE, to stop the capture, and set
2287 "ld->err" to the error. */
2288 if (!wtap_dump(ld->pdh, &whdr, &pseudo_header, pd, &err)) {
2294 switch (ld->linktype) {
2295 case WTAP_ENCAP_ETHERNET:
2296 capture_eth(pd, 0, whdr.caplen, &ld->counts);
2298 case WTAP_ENCAP_FDDI:
2299 case WTAP_ENCAP_FDDI_BITSWAPPED:
2300 capture_fddi(pd, whdr.caplen, &ld->counts);
2302 case WTAP_ENCAP_PRISM_HEADER:
2303 capture_prism(pd, 0, whdr.caplen, &ld->counts);
2305 case WTAP_ENCAP_TOKEN_RING:
2306 capture_tr(pd, 0, whdr.caplen, &ld->counts);
2308 case WTAP_ENCAP_NULL:
2309 capture_null(pd, whdr.caplen, &ld->counts);
2311 case WTAP_ENCAP_PPP:
2312 capture_ppp_hdlc(pd, 0, whdr.caplen, &ld->counts);
2314 case WTAP_ENCAP_RAW_IP:
2315 capture_raw(pd, whdr.caplen, &ld->counts);
2317 case WTAP_ENCAP_SLL:
2318 capture_sll(pd, whdr.caplen, &ld->counts);
2320 case WTAP_ENCAP_LINUX_ATM_CLIP:
2321 capture_clip(pd, whdr.caplen, &ld->counts);
2323 case WTAP_ENCAP_IEEE_802_11:
2324 case WTAP_ENCAP_IEEE_802_11_WITH_RADIO:
2325 capture_ieee80211(pd, 0, whdr.caplen, &ld->counts);
2327 case WTAP_ENCAP_CHDLC:
2328 capture_chdlc(pd, 0, whdr.caplen, &ld->counts);
2330 case WTAP_ENCAP_LOCALTALK:
2331 capture_llap(&ld->counts);
2333 case WTAP_ENCAP_ATM_PDUS:
2334 capture_atm(&pseudo_header, pd, whdr.caplen, &ld->counts);
2336 case WTAP_ENCAP_IP_OVER_FC:
2337 capture_ipfc(pd, whdr.caplen, &ld->counts);
2339 case WTAP_ENCAP_ARCNET:
2340 capture_arcnet(pd, whdr.caplen, &ld->counts, FALSE, TRUE);
2342 case WTAP_ENCAP_ARCNET_LINUX:
2343 capture_arcnet(pd, whdr.caplen, &ld->counts, TRUE, FALSE);
2345 case WTAP_ENCAP_APPLE_IP_OVER_IEEE1394:
2346 capture_ap1394(pd, 0, whdr.caplen, &ld->counts);
2348 /* XXX - some ATM drivers on FreeBSD might prepend a 4-byte ATM
2349 pseudo-header to DLT_ATM_RFC1483, with LLC header following;
2350 we might have to implement that at some point. */
2354 #endif /* HAVE_LIBPCAP */