2 * Synchronisation between Wireshark capture parent and child instances
6 * Wireshark - Network traffic analyzer
7 * By Gerald Combs <gerald@wireshark.org>
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.
47 #include <wsutil/unicode-utils.h>
50 #ifdef HAVE_SYS_WAIT_H
51 # include <sys/wait.h>
54 #include "capture-pcap-util.h"
58 * Define various POSIX macros (and, in the case of WCOREDUMP, non-POSIX
59 * macros) on UNIX systems that don't have them.
62 # define WIFEXITED(status) (((status) & 0177) == 0)
65 # define WIFSTOPPED(status) (((status) & 0177) == 0177)
68 # define WIFSIGNALED(status) (!WIFSTOPPED(status) && !WIFEXITED(status))
71 # define WEXITSTATUS(status) ((status) >> 8)
74 # define WTERMSIG(status) ((status) & 0177)
77 # define WCOREDUMP(status) ((status) & 0200)
80 # define WSTOPSIG(status) ((status) >> 8)
84 #include <epan/packet.h>
85 #include <epan/prefs.h>
89 #include <epan/filesystem.h>
90 #include <epan/report_err.h>
93 #include "capture_sync.h"
95 #include "sync_pipe.h"
98 #include "capture-wpcap.h"
101 #include "ui/ui_util.h"
103 #include <wsutil/file_util.h>
107 #include <process.h> /* For spawning child process */
113 static const char *sync_pipe_signame(int);
117 static gboolean sync_pipe_input_cb(gint source, gpointer user_data);
118 static int sync_pipe_wait_for_child(int fork_child, gchar **msgp);
119 static void pipe_convert_header(const guchar *header, int header_len, char *indicator, int *block_len);
120 static int pipe_read_block(int pipe_fd, char *indicator, int len, char *msg,
125 /* Append an arg (realloc) to an argc/argv array */
126 /* (add a string pointer to a NULL-terminated array of string pointers) */
128 sync_pipe_add_arg(const char **args, int *argc, const char *arg)
130 /* Grow the array; "*argc" currently contains the number of string
131 pointers, *not* counting the NULL pointer at the end, so we have
132 to add 2 in order to get the new size of the array, including the
133 new pointer and the terminating NULL pointer. */
134 args = g_realloc( (gpointer) args, (*argc + 2) * sizeof (char *));
136 /* Stuff the pointer into the penultimate element of the array, which
137 is the one at the index specified by "*argc". */
138 args[*argc] = g_strdup(arg);
139 /* Now bump the count. */
142 /* We overwrite the NULL pointer; put it back right after the
152 /* Quote the argument element if necessary, so that it will get
153 * reconstructed correctly in the C runtime startup code. Note that
154 * the unquoting algorithm in the C runtime is really weird, and
155 * rather different than what Unix shells do. See stdargv.c in the C
156 * runtime sources (in the Platform SDK, in src/crt).
158 * Stolen from GLib's protect_argv(), an internal routine that quotes
159 * string in an argument list so that they arguments will be handled
160 * correctly in the command-line string passed to CreateProcess()
161 * if that string is constructed by gluing those strings together.
164 protect_arg (const gchar *argv)
167 const gchar *p = argv;
170 gboolean need_dblquotes = FALSE;
173 if (*p == ' ' || *p == '\t')
174 need_dblquotes = TRUE;
177 else if (*p == '\\') {
180 while (*pp && *pp == '\\')
189 q = new_arg = g_malloc (len + need_dblquotes*2 + 1);
198 else if (*p == '\\') {
201 while (*pp && *pp == '\\')
218 * Generate a string for a Win32 error.
220 #define ERRBUF_SIZE 1024
222 win32strerror(DWORD error)
224 static char errbuf[ERRBUF_SIZE+1];
228 FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, errbuf,
232 * "FormatMessage()" "helpfully" sticks CR/LF at the end of the
233 * message. Get rid of it.
235 errlen = strlen(errbuf);
237 errbuf[errlen - 1] = '\0';
238 errbuf[errlen - 2] = '\0';
240 p = strchr(errbuf, '\0');
241 g_snprintf(p, (gulong)(sizeof errbuf - (p-errbuf)), " (%lu)", error);
246 * Generate a string for a Win32 exception code.
249 win32strexception(DWORD exception)
251 static char errbuf[ERRBUF_SIZE+1];
252 static const struct exception_msg {
256 { EXCEPTION_ACCESS_VIOLATION, "Access violation" },
257 { EXCEPTION_ARRAY_BOUNDS_EXCEEDED, "Array bounds exceeded" },
258 { EXCEPTION_BREAKPOINT, "Breakpoint" },
259 { EXCEPTION_DATATYPE_MISALIGNMENT, "Data type misalignment" },
260 { EXCEPTION_FLT_DENORMAL_OPERAND, "Denormal floating-point operand" },
261 { EXCEPTION_FLT_DIVIDE_BY_ZERO, "Floating-point divide by zero" },
262 { EXCEPTION_FLT_INEXACT_RESULT, "Floating-point inexact result" },
263 { EXCEPTION_FLT_INVALID_OPERATION, "Invalid floating-point operation" },
264 { EXCEPTION_FLT_OVERFLOW, "Floating-point overflow" },
265 { EXCEPTION_FLT_STACK_CHECK, "Floating-point stack check" },
266 { EXCEPTION_FLT_UNDERFLOW, "Floating-point underflow" },
267 { EXCEPTION_GUARD_PAGE, "Guard page violation" },
268 { EXCEPTION_ILLEGAL_INSTRUCTION, "Illegal instruction" },
269 { EXCEPTION_IN_PAGE_ERROR, "Page-in error" },
270 { EXCEPTION_INT_DIVIDE_BY_ZERO, "Integer divide by zero" },
271 { EXCEPTION_INT_OVERFLOW, "Integer overflow" },
272 { EXCEPTION_INVALID_DISPOSITION, "Invalid disposition" },
273 { EXCEPTION_INVALID_HANDLE, "Invalid handle" },
274 { EXCEPTION_NONCONTINUABLE_EXCEPTION, "Non-continuable exception" },
275 { EXCEPTION_PRIV_INSTRUCTION, "Privileged instruction" },
276 { EXCEPTION_SINGLE_STEP, "Single-step complete" },
277 { EXCEPTION_STACK_OVERFLOW, "Stack overflow" },
280 #define N_EXCEPTIONS (sizeof exceptions / sizeof exceptions[0])
283 for (i = 0; i < N_EXCEPTIONS; i++) {
284 if (exceptions[i].code == exception)
285 return exceptions[i].msg;
287 g_snprintf(errbuf, (gulong)sizeof errbuf, "Exception 0x%08x", exception);
292 /* Initialize an argument list and add dumpcap to it. */
294 init_pipe_args(int *argc) {
296 const char *progfile_dir;
299 progfile_dir = get_progfile_dir();
300 if (progfile_dir == NULL) {
304 /* Allocate the string pointer array with enough space for the
305 terminating NULL pointer. */
307 argv = g_malloc(sizeof (char *));
310 /* take Wireshark's absolute program path and replace "Wireshark" with "dumpcap" */
311 exename = g_strdup_printf("%s" G_DIR_SEPARATOR_S "dumpcap", progfile_dir);
313 /* Make that the first argument in the argument list (argv[0]). */
314 argv = sync_pipe_add_arg(argv, argc, exename);
319 #define ARGV_NUMBER_LEN 24
320 /* a new capture run: start a new dumpcap task and hand over parameters through command line */
322 sync_pipe_start(capture_options *capture_opts) {
323 char ssnap[ARGV_NUMBER_LEN];
324 char sdlt[ARGV_NUMBER_LEN];
325 char scount[ARGV_NUMBER_LEN];
326 char sfilesize[ARGV_NUMBER_LEN];
327 char sfile_duration[ARGV_NUMBER_LEN];
328 char sring_num_files[ARGV_NUMBER_LEN];
329 char sautostop_files[ARGV_NUMBER_LEN];
330 char sautostop_filesize[ARGV_NUMBER_LEN];
331 char sautostop_duration[ARGV_NUMBER_LEN];
332 #ifdef HAVE_PCAP_REMOTE
335 #ifdef HAVE_PCAP_SETSAMPLING
336 char ssampling[ARGV_NUMBER_LEN];
339 #if defined(_WIN32) || defined(HAVE_PCAP_CREATE)
340 char buffer_size[ARGV_NUMBER_LEN];
344 HANDLE sync_pipe_read; /* pipe used to send messages from child to parent */
345 HANDLE sync_pipe_write; /* pipe used to send messages from child to parent */
346 HANDLE signal_pipe; /* named pipe used to send messages from parent to child (currently only stop) */
347 GString *args = g_string_sized_new(200);
349 SECURITY_ATTRIBUTES sa;
351 PROCESS_INFORMATION pi;
352 char control_id[ARGV_NUMBER_LEN];
353 gchar *signal_pipe_name;
356 int sync_pipe[2]; /* pipe used to send messages from child to parent */
357 enum PIPES { PIPE_READ, PIPE_WRITE }; /* Constants 0 and 1 for PIPE_READ and PIPE_WRITE */
359 int sync_pipe_read_fd;
364 interface_options interface_opts;
366 if (capture_opts->ifaces->len > 1)
367 capture_opts->use_pcapng = TRUE;
368 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "sync_pipe_start");
369 capture_opts_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, capture_opts);
371 capture_opts->fork_child = -1;
373 argv = init_pipe_args(&argc);
375 /* We don't know where to find dumpcap. */
376 report_failure("We don't know where to find dumpcap.");
380 if (capture_opts->ifaces->len > 1)
381 argv = sync_pipe_add_arg(argv, &argc, "-t");
383 if (capture_opts->use_pcapng)
384 argv = sync_pipe_add_arg(argv, &argc, "-n");
386 argv = sync_pipe_add_arg(argv, &argc, "-P");
388 if (capture_opts->multi_files_on) {
389 if (capture_opts->has_autostop_filesize) {
390 argv = sync_pipe_add_arg(argv, &argc, "-b");
391 g_snprintf(sfilesize, ARGV_NUMBER_LEN, "filesize:%d",capture_opts->autostop_filesize);
392 argv = sync_pipe_add_arg(argv, &argc, sfilesize);
395 if (capture_opts->has_file_duration) {
396 argv = sync_pipe_add_arg(argv, &argc, "-b");
397 g_snprintf(sfile_duration, ARGV_NUMBER_LEN, "duration:%d",capture_opts->file_duration);
398 argv = sync_pipe_add_arg(argv, &argc, sfile_duration);
401 if (capture_opts->has_ring_num_files) {
402 argv = sync_pipe_add_arg(argv, &argc, "-b");
403 g_snprintf(sring_num_files, ARGV_NUMBER_LEN, "files:%d",capture_opts->ring_num_files);
404 argv = sync_pipe_add_arg(argv, &argc, sring_num_files);
407 if (capture_opts->has_autostop_files) {
408 argv = sync_pipe_add_arg(argv, &argc, "-a");
409 g_snprintf(sautostop_files, ARGV_NUMBER_LEN, "files:%d",capture_opts->autostop_files);
410 argv = sync_pipe_add_arg(argv, &argc, sautostop_files);
413 if (capture_opts->has_autostop_filesize) {
414 argv = sync_pipe_add_arg(argv, &argc, "-a");
415 g_snprintf(sautostop_filesize, ARGV_NUMBER_LEN, "filesize:%d",capture_opts->autostop_filesize);
416 argv = sync_pipe_add_arg(argv, &argc, sautostop_filesize);
420 if (capture_opts->has_autostop_packets) {
421 argv = sync_pipe_add_arg(argv, &argc, "-c");
422 g_snprintf(scount, ARGV_NUMBER_LEN, "%d",capture_opts->autostop_packets);
423 argv = sync_pipe_add_arg(argv, &argc, scount);
426 if (capture_opts->has_autostop_duration) {
427 argv = sync_pipe_add_arg(argv, &argc, "-a");
428 g_snprintf(sautostop_duration, ARGV_NUMBER_LEN, "duration:%d",capture_opts->autostop_duration);
429 argv = sync_pipe_add_arg(argv, &argc, sautostop_duration);
432 for (j = 0; j < capture_opts->ifaces->len; j++) {
433 interface_opts = g_array_index(capture_opts->ifaces, interface_options, j);
435 argv = sync_pipe_add_arg(argv, &argc, "-i");
436 argv = sync_pipe_add_arg(argv, &argc, interface_opts.name);
438 if (interface_opts.cfilter != NULL && strlen(interface_opts.cfilter) != 0) {
439 argv = sync_pipe_add_arg(argv, &argc, "-f");
440 argv = sync_pipe_add_arg(argv, &argc, interface_opts.cfilter);
442 if (interface_opts.snaplen != WTAP_MAX_PACKET_SIZE) {
443 argv = sync_pipe_add_arg(argv, &argc, "-s");
444 g_snprintf(ssnap, ARGV_NUMBER_LEN, "%d", interface_opts.snaplen);
445 argv = sync_pipe_add_arg(argv, &argc, ssnap);
448 if (interface_opts.linktype != -1) {
449 argv = sync_pipe_add_arg(argv, &argc, "-y");
450 g_snprintf(sdlt, ARGV_NUMBER_LEN, "%s", linktype_val_to_name(interface_opts.linktype));
451 argv = sync_pipe_add_arg(argv, &argc, sdlt);
454 if (!interface_opts.promisc_mode) {
455 argv = sync_pipe_add_arg(argv, &argc, "-p");
458 #if defined(_WIN32) || defined(HAVE_PCAP_CREATE)
459 if (interface_opts.buffer_size != 1) {
460 argv = sync_pipe_add_arg(argv, &argc, "-B");
461 g_snprintf(buffer_size, ARGV_NUMBER_LEN, "%d", interface_opts.buffer_size);
462 argv = sync_pipe_add_arg(argv, &argc, buffer_size);
466 if (interface_opts.monitor_mode) {
467 argv = sync_pipe_add_arg(argv, &argc, "-I");
470 #ifdef HAVE_PCAP_REMOTE
471 if (interface_opts.datatx_udp)
472 argv = sync_pipe_add_arg(argv, &argc, "-u");
474 if (!interface_opts.nocap_rpcap)
475 argv = sync_pipe_add_arg(argv, &argc, "-r");
477 if (interface_opts.auth_type == CAPTURE_AUTH_PWD) {
478 argv = sync_pipe_add_arg(argv, &argc, "-A");
479 g_snprintf(sauth, sizeof(sauth), "%s:%s",
480 interface_opts.auth_username,
481 interface_opts.auth_password);
482 argv = sync_pipe_add_arg(argv, &argc, sauth);
486 #ifdef HAVE_PCAP_SETSAMPLING
487 if (interface_opts.sampling_method != CAPTURE_SAMP_NONE) {
488 argv = sync_pipe_add_arg(argv, &argc, "-m");
489 g_snprintf(ssampling, ARGV_NUMBER_LEN, "%s:%d",
490 interface_opts.sampling_method == CAPTURE_SAMP_BY_COUNT ? "count" :
491 interface_opts.sampling_method == CAPTURE_SAMP_BY_TIMER ? "timer" :
493 interface_opts.sampling_param);
494 argv = sync_pipe_add_arg(argv, &argc, ssampling);
499 /* dumpcap should be running in capture child mode (hidden feature) */
501 argv = sync_pipe_add_arg(argv, &argc, "-Z");
503 g_snprintf(control_id, ARGV_NUMBER_LEN, "%d", GetCurrentProcessId());
504 argv = sync_pipe_add_arg(argv, &argc, control_id);
506 argv = sync_pipe_add_arg(argv, &argc, SIGNAL_PIPE_CTRL_ID_NONE);
510 if (capture_opts->save_file) {
511 argv = sync_pipe_add_arg(argv, &argc, "-w");
512 argv = sync_pipe_add_arg(argv, &argc, capture_opts->save_file);
514 for (i = 0; i < argc; i++) {
515 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "argv[%d]: %s", i, argv[i]);
519 /* init SECURITY_ATTRIBUTES */
520 sa.nLength = sizeof(SECURITY_ATTRIBUTES);
521 sa.bInheritHandle = TRUE;
522 sa.lpSecurityDescriptor = NULL;
524 /* Create a pipe for the child process */
525 /* (increase this value if you have trouble while fast capture file switches) */
526 if (! CreatePipe(&sync_pipe_read, &sync_pipe_write, &sa, 5120)) {
527 /* Couldn't create the pipe between parent and child. */
528 report_failure("Couldn't create sync pipe: %s",
529 win32strerror(GetLastError()));
530 for (i = 0; i < argc; i++) {
531 g_free( (gpointer) argv[i]);
533 g_free( (gpointer) argv);
537 /* Create the signal pipe */
538 signal_pipe_name = g_strdup_printf(SIGNAL_PIPE_FORMAT, control_id);
539 signal_pipe = CreateNamedPipe(utf_8to16(signal_pipe_name),
540 PIPE_ACCESS_OUTBOUND, PIPE_TYPE_BYTE, 1, 65535, 65535, 0, NULL);
541 g_free(signal_pipe_name);
543 if (signal_pipe == INVALID_HANDLE_VALUE) {
544 /* Couldn't create the signal pipe between parent and child. */
545 report_failure("Couldn't create signal pipe: %s",
546 win32strerror(GetLastError()));
547 for (i = 0; i < argc; i++) {
548 g_free( (gpointer) argv[i]);
550 g_free( (gpointer) argv);
554 /* init STARTUPINFO */
555 memset(&si, 0, sizeof(si));
558 si.dwFlags = STARTF_USESHOWWINDOW;
559 si.wShowWindow = SW_SHOW;
561 si.dwFlags = STARTF_USESTDHANDLES|STARTF_USESHOWWINDOW;
562 si.wShowWindow = SW_HIDE; /* this hides the console window */
563 si.hStdInput = GetStdHandle(STD_INPUT_HANDLE);
564 si.hStdOutput = GetStdHandle(STD_OUTPUT_HANDLE);
565 si.hStdError = sync_pipe_write;
566 /*si.hStdError = (HANDLE) _get_osfhandle(2);*/
569 /* convert args array into a single string */
570 /* XXX - could change sync_pipe_add_arg() instead */
571 /* there is a drawback here: the length is internally limited to 1024 bytes */
572 for(i=0; argv[i] != 0; i++) {
573 if(i != 0) g_string_append_c(args, ' '); /* don't prepend a space before the path!!! */
574 quoted_arg = protect_arg(argv[i]);
575 g_string_append(args, quoted_arg);
580 if(!CreateProcess(NULL, utf_8to16(args->str), NULL, NULL, TRUE,
581 CREATE_NEW_CONSOLE, NULL, NULL, &si, &pi)) {
582 report_failure("Couldn't run %s in child process: %s",
583 args->str, win32strerror(GetLastError()));
584 CloseHandle(sync_pipe_read);
585 CloseHandle(sync_pipe_write);
586 for (i = 0; i < argc; i++) {
587 g_free( (gpointer) argv[i]);
589 g_free( (gpointer) argv);
592 capture_opts->fork_child = (int) pi.hProcess;
593 g_string_free(args, TRUE);
595 /* associate the operating system filehandle to a C run-time file handle */
596 /* (good file handle infos at: http://www.flounder.com/handles.htm) */
597 sync_pipe_read_fd = _open_osfhandle( (long) sync_pipe_read, _O_BINARY);
599 /* associate the operating system filehandle to a C run-time file handle */
600 capture_opts->signal_pipe_write_fd = _open_osfhandle( (long) signal_pipe, _O_BINARY);
603 if (pipe(sync_pipe) < 0) {
604 /* Couldn't create the pipe between parent and child. */
605 report_failure("Couldn't create sync pipe: %s", g_strerror(errno));
606 for (i = 0; i < argc; i++) {
607 g_free( (gpointer) argv[i]);
613 if ((capture_opts->fork_child = fork()) == 0) {
615 * Child process - run dumpcap with the right arguments to make
616 * it just capture with the specified capture parameters
618 dup2(sync_pipe[PIPE_WRITE], 2);
619 ws_close(sync_pipe[PIPE_READ]);
620 execv(argv[0], (gpointer)argv);
621 g_snprintf(errmsg, sizeof errmsg, "Couldn't run %s in child process: %s",
622 argv[0], g_strerror(errno));
623 sync_pipe_errmsg_to_parent(2, errmsg, "");
625 /* Exit with "_exit()", so that we don't close the connection
626 to the X server (and cause stuff buffered up by our parent but
627 not yet sent to be sent, as that stuff should only be sent by
628 our parent). We've sent an error message to the parent, so
629 we exit with an exit status of 1 (any exit status other than
630 0 or 1 will cause an additional message to report that exit
631 status, over and above the error message we sent to the parent). */
635 sync_pipe_read_fd = sync_pipe[PIPE_READ];
638 for (i = 0; i < argc; i++) {
639 g_free( (gpointer) argv[i]);
642 /* Parent process - read messages from the child process over the
644 g_free( (gpointer) argv); /* free up arg array */
646 /* Close the write side of the pipe, so that only the child has it
647 open, and thus it completely closes, and thus returns to us
648 an EOF indication, if the child closes it (either deliberately
649 or by exiting abnormally). */
651 CloseHandle(sync_pipe_write);
653 ws_close(sync_pipe[PIPE_WRITE]);
656 if (capture_opts->fork_child == -1) {
657 /* We couldn't even create the child process. */
658 report_failure("Couldn't create child process: %s", g_strerror(errno));
659 ws_close(sync_pipe_read_fd);
661 ws_close(capture_opts->signal_pipe_write_fd);
666 capture_opts->fork_child_status = 0;
668 /* we might wait for a moment till child is ready, so update screen now */
669 main_window_update();
671 /* We were able to set up to read the capture file;
672 arrange that our callback be called whenever it's possible
673 to read from the sync pipe, so that it's called when
674 the child process wants to tell us something. */
676 /* we have a running capture, now wait for the real capture filename */
677 pipe_input_set_handler(sync_pipe_read_fd, (gpointer) capture_opts,
678 &capture_opts->fork_child, sync_pipe_input_cb);
684 * Open two pipes to dumpcap with the supplied arguments, one for its
685 * standard output and one for its standard error.
687 * On success, *msg is unchanged and 0 is returned; data_read_fd,
688 * messsage_read_fd, and fork_child point to the standard output pipe's
689 * file descriptor, the standard error pipe's file descriptor, and
690 * the child's PID/handle, respectively.
692 * On failure, *msg points to an error message for the failure, and -1 is
693 * returned, in which case *msg must be freed with g_free().
695 /* XXX - This duplicates a lot of code in sync_pipe_start() */
696 /* XXX - assumes PIPE_BUF_SIZE > SP_MAX_MSG_LEN */
697 #define PIPE_BUF_SIZE 5120
699 sync_pipe_open_command(const char** argv, int *data_read_fd,
700 int *message_read_fd, int *fork_child, gchar **msg)
702 enum PIPES { PIPE_READ, PIPE_WRITE }; /* Constants 0 and 1 for PIPE_READ and PIPE_WRITE */
704 HANDLE sync_pipe[2]; /* pipe used to send messages from child to parent */
705 HANDLE data_pipe[2]; /* pipe used to send data from child to parent */
706 GString *args = g_string_sized_new(200);
708 SECURITY_ATTRIBUTES sa;
710 PROCESS_INFORMATION pi;
713 int sync_pipe[2]; /* pipe used to send messages from child to parent */
714 int data_pipe[2]; /* pipe used to send data from child to parent */
719 *message_read_fd = -1;
720 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "sync_pipe_open_command");
723 /* We can't return anything */
725 g_string_free(args, TRUE);
731 /* init SECURITY_ATTRIBUTES */
732 sa.nLength = sizeof(SECURITY_ATTRIBUTES);
733 sa.bInheritHandle = TRUE;
734 sa.lpSecurityDescriptor = NULL;
736 /* Create a pipe for the child process to send us messages */
737 /* (increase this value if you have trouble while fast capture file switches) */
738 if (! CreatePipe(&sync_pipe[PIPE_READ], &sync_pipe[PIPE_WRITE], &sa, 5120)) {
739 /* Couldn't create the message pipe between parent and child. */
740 *msg = g_strdup_printf("Couldn't create sync pipe: %s",
741 win32strerror(GetLastError()));
742 for (i = 0; argv[i] != NULL; i++) {
743 g_free( (gpointer) argv[i]);
745 g_free( (gpointer) argv);
749 /* Create a pipe for the child process to send us data */
750 /* (increase this value if you have trouble while fast capture file switches) */
751 if (! CreatePipe(&data_pipe[PIPE_READ], &data_pipe[PIPE_WRITE], &sa, 5120)) {
752 /* Couldn't create the message pipe between parent and child. */
753 *msg = g_strdup_printf("Couldn't create data pipe: %s",
754 win32strerror(GetLastError()));
755 CloseHandle(sync_pipe[PIPE_READ]);
756 CloseHandle(sync_pipe[PIPE_WRITE]);
757 for (i = 0; argv[i] != NULL; i++) {
758 g_free( (gpointer) argv[i]);
760 g_free( (gpointer) argv);
764 /* init STARTUPINFO */
765 memset(&si, 0, sizeof(si));
768 si.dwFlags = STARTF_USESHOWWINDOW;
769 si.wShowWindow = SW_SHOW;
771 si.dwFlags = STARTF_USESTDHANDLES|STARTF_USESHOWWINDOW;
772 si.wShowWindow = SW_HIDE; /* this hides the console window */
774 si.hStdOutput = data_pipe[PIPE_WRITE];
775 si.hStdError = sync_pipe[PIPE_WRITE];
778 /* convert args array into a single string */
779 /* XXX - could change sync_pipe_add_arg() instead */
780 /* there is a drawback here: the length is internally limited to 1024 bytes */
781 for(i=0; argv[i] != 0; i++) {
782 if(i != 0) g_string_append_c(args, ' '); /* don't prepend a space before the path!!! */
783 quoted_arg = protect_arg(argv[i]);
784 g_string_append(args, quoted_arg);
789 if(!CreateProcess(NULL, utf_8to16(args->str), NULL, NULL, TRUE,
790 CREATE_NEW_CONSOLE, NULL, NULL, &si, &pi)) {
791 *msg = g_strdup_printf("Couldn't run %s in child process: %s",
792 args->str, win32strerror(GetLastError()));
793 CloseHandle(data_pipe[PIPE_READ]);
794 CloseHandle(data_pipe[PIPE_WRITE]);
795 CloseHandle(sync_pipe[PIPE_READ]);
796 CloseHandle(sync_pipe[PIPE_WRITE]);
797 for (i = 0; argv[i] != NULL; i++) {
798 g_free( (gpointer) argv[i]);
800 g_free( (gpointer) argv);
803 *fork_child = (int) pi.hProcess;
804 g_string_free(args, TRUE);
806 /* associate the operating system filehandles to C run-time file handles */
807 /* (good file handle infos at: http://www.flounder.com/handles.htm) */
808 *data_read_fd = _open_osfhandle( (long) data_pipe[PIPE_READ], _O_BINARY);
809 *message_read_fd = _open_osfhandle( (long) sync_pipe[PIPE_READ], _O_BINARY);
811 /* Create a pipe for the child process to send us messages */
812 if (pipe(sync_pipe) < 0) {
813 /* Couldn't create the message pipe between parent and child. */
814 *msg = g_strdup_printf("Couldn't create sync pipe: %s", g_strerror(errno));
815 for (i = 0; argv[i] != NULL; i++) {
816 g_free( (gpointer) argv[i]);
822 /* Create a pipe for the child process to send us data */
823 if (pipe(data_pipe) < 0) {
824 /* Couldn't create the data pipe between parent and child. */
825 *msg = g_strdup_printf("Couldn't create data pipe: %s", g_strerror(errno));
826 ws_close(sync_pipe[PIPE_READ]);
827 ws_close(sync_pipe[PIPE_WRITE]);
828 for (i = 0; argv[i] != NULL; i++) {
829 g_free( (gpointer) argv[i]);
835 if ((*fork_child = fork()) == 0) {
837 * Child process - run dumpcap with the right arguments to make
838 * it just capture with the specified capture parameters
840 dup2(data_pipe[PIPE_WRITE], 1);
841 ws_close(data_pipe[PIPE_READ]);
842 ws_close(data_pipe[PIPE_WRITE]);
843 dup2(sync_pipe[PIPE_WRITE], 2);
844 ws_close(sync_pipe[PIPE_READ]);
845 ws_close(sync_pipe[PIPE_WRITE]);
846 execv(argv[0], (gpointer)argv);
847 g_snprintf(errmsg, sizeof errmsg, "Couldn't run %s in child process: %s",
848 argv[0], g_strerror(errno));
849 sync_pipe_errmsg_to_parent(2, errmsg, "");
851 /* Exit with "_exit()", so that we don't close the connection
852 to the X server (and cause stuff buffered up by our parent but
853 not yet sent to be sent, as that stuff should only be sent by
854 our parent). We've sent an error message to the parent, so
855 we exit with an exit status of 1 (any exit status other than
856 0 or 1 will cause an additional message to report that exit
857 status, over and above the error message we sent to the parent). */
861 *data_read_fd = data_pipe[PIPE_READ];
862 *message_read_fd = sync_pipe[PIPE_READ];
865 for (i = 0; argv[i] != NULL; i++) {
866 g_free( (gpointer) argv[i]);
869 /* Parent process - read messages from the child process over the
871 g_free( (gpointer) argv); /* free up arg array */
873 /* Close the write sides of the pipes, so that only the child has them
874 open, and thus they completely close, and thus return to us
875 an EOF indication, if the child closes them (either deliberately
876 or by exiting abnormally). */
878 CloseHandle(data_pipe[PIPE_WRITE]);
879 CloseHandle(sync_pipe[PIPE_WRITE]);
881 ws_close(data_pipe[PIPE_WRITE]);
882 ws_close(sync_pipe[PIPE_WRITE]);
885 if (*fork_child == -1) {
886 /* We couldn't even create the child process. */
887 *msg = g_strdup_printf("Couldn't create child process: %s", g_strerror(errno));
888 ws_close(*data_read_fd);
889 ws_close(*message_read_fd);
893 /* we might wait for a moment till child is ready, so update screen now */
894 main_window_update();
899 * Close the pipes we're using to read from dumpcap, and wait for it
900 * to exit. On success, *msgp is unchanged, and the exit status of
901 * dumpcap is returned. On failure (which includes "dumpcap exited
902 * due to being killed by a signal or an exception"), *msgp points
903 * to an error message for the failure, and -1 is returned. In the
904 * latter case, *msgp must be freed with g_free().
907 sync_pipe_close_command(int *data_read_fd, int *message_read_fd,
908 int *fork_child, gchar **msgp)
910 ws_close(*data_read_fd);
911 if (message_read_fd != NULL)
912 ws_close(*message_read_fd);
915 /* XXX - Should we signal the child somehow? */
916 sync_pipe_kill(*fork_child);
919 return sync_pipe_wait_for_child(*fork_child, msgp);
923 * Run dumpcap with the supplied arguments.
925 * On success, *data points to a buffer containing the dumpcap output,
926 * *primary_msg and *secondary_message are NULL, and 0 is returned; *data
927 * must be freed with g_free().
929 * On failure, *data is NULL, *primary_msg points to an error message,
930 * *secondary_msg either points to an additional error message or is
931 * NULL, and -1 is returned; *primary_msg, and *secondary_msg if not NULL,
932 * must be freed with g_free().
934 /* XXX - This duplicates a lot of code in sync_pipe_start() */
935 /* XXX - assumes PIPE_BUF_SIZE > SP_MAX_MSG_LEN */
936 #define PIPE_BUF_SIZE 5120
938 sync_pipe_run_command(const char** argv, gchar **data, gchar **primary_msg,
939 gchar **secondary_msg)
942 int data_pipe_read_fd, sync_pipe_read_fd, fork_child, ret;
944 gchar buffer[PIPE_BUF_SIZE+1];
948 char *primary_msg_text;
949 int secondary_msg_len;
950 char *secondary_msg_text;
952 GString *data_buf = NULL;
955 ret = sync_pipe_open_command(argv, &data_pipe_read_fd, &sync_pipe_read_fd,
959 *secondary_msg = NULL;
965 * We were able to set up to read dumpcap's output. Do so.
967 * First, wait for an SP_ERROR_MSG message or SP_SUCCESS message.
969 nread = pipe_read_block(sync_pipe_read_fd, &indicator, SP_MAX_MSG_LEN,
970 buffer, primary_msg);
972 /* We got a read error from the sync pipe, or we got no data at
973 all from the sync pipe, so we're not going to be getting any
974 data or error message from the child process. Pick up its
975 exit status, and complain.
977 We don't have to worry about killing the child, if the sync pipe
978 returned an error. Usually this error is caused as the child killed
979 itself while going down. Even in the rare cases that this isn't the
980 case, the child will get an error when writing to the broken pipe
981 the next time, cleaning itself up then. */
982 ret = sync_pipe_wait_for_child(fork_child, &wait_msg);
984 /* We got an EOF from the sync pipe. That means that it exited
985 before giving us any data to read. If ret is -1, we report
986 that as a bad exit (e.g., exiting due to a signal); otherwise,
987 we report it as a premature exit. */
989 *primary_msg = wait_msg;
991 *primary_msg = g_strdup("Child dumpcap closed sync pipe prematurely");
993 /* We got an error from the sync pipe. If ret is -1, report
994 both the sync pipe I/O error and the wait error. */
996 combined_msg = g_strdup_printf("%s\n\n%s", *primary_msg, wait_msg);
997 g_free(*primary_msg);
999 *primary_msg = combined_msg;
1002 *secondary_msg = NULL;
1007 /* we got a valid message block from the child, process it */
1012 * Error from dumpcap; there will be a primary message and a
1013 * secondary message.
1016 /* convert primary message */
1017 pipe_convert_header(buffer, 4, &indicator, &primary_msg_len);
1018 primary_msg_text = buffer+4;
1019 /* convert secondary message */
1020 pipe_convert_header(primary_msg_text + primary_msg_len, 4, &indicator,
1021 &secondary_msg_len);
1022 secondary_msg_text = primary_msg_text + primary_msg_len + 4;
1023 /* the capture child will close the sync_pipe, nothing to do */
1026 * Pick up the child status.
1028 ret = sync_pipe_close_command(&data_pipe_read_fd, &sync_pipe_read_fd,
1032 * Child process failed unexpectedly, or wait failed; msg is the
1036 *secondary_msg = NULL;
1039 * Child process failed, but returned the expected exit status.
1040 * Return the messages it gave us, and indicate failure.
1042 *primary_msg = g_strdup(primary_msg_text);
1043 *secondary_msg = g_strdup(secondary_msg_text);
1050 /* read the output from the command */
1051 data_buf = g_string_new("");
1052 while ((count = ws_read(data_pipe_read_fd, buffer, PIPE_BUF_SIZE)) > 0) {
1053 buffer[count] = '\0';
1054 g_string_append(data_buf, buffer);
1058 * Pick up the child status.
1060 ret = sync_pipe_close_command(&data_pipe_read_fd, &sync_pipe_read_fd,
1064 * Child process failed unexpectedly, or wait failed; msg is the
1068 *secondary_msg = NULL;
1069 g_string_free(data_buf, TRUE);
1073 * Child process succeeded.
1075 *primary_msg = NULL;
1076 *secondary_msg = NULL;
1077 *data = data_buf->str;
1078 g_string_free(data_buf, FALSE);
1084 * Pick up the child status.
1086 ret = sync_pipe_close_command(&data_pipe_read_fd, &sync_pipe_read_fd,
1090 * Child process failed unexpectedly, or wait failed; msg is the
1094 *secondary_msg = NULL;
1097 * Child process returned an unknown status.
1099 *primary_msg = g_strdup_printf("dumpcap process gave an unexpected message type: 0x%02x",
1101 *secondary_msg = NULL;
1111 * Get the list of interfaces using dumpcap.
1113 * On success, *data points to a buffer containing the dumpcap output,
1114 * *primary_msg and *secondary_msg are NULL, and 0 is returned. *data
1115 * must be freed with g_free().
1117 * On failure, *data is NULL, *primary_msg points to an error message,
1118 * *secondary_msg either points to an additional error message or is
1119 * NULL, and -1 is returned; *primary_msg, and *secondary_msg if not NULL,
1120 * must be freed with g_free().
1123 sync_interface_list_open(gchar **data, gchar **primary_msg,
1124 gchar **secondary_msg)
1129 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "sync_interface_list_open");
1131 argv = init_pipe_args(&argc);
1134 *primary_msg = g_strdup("We don't know where to find dumpcap.");
1135 *secondary_msg = NULL;
1140 /* Ask for the interface list */
1141 argv = sync_pipe_add_arg(argv, &argc, "-D");
1144 /* Run dumpcap in capture child mode */
1145 argv = sync_pipe_add_arg(argv, &argc, "-Z");
1146 argv = sync_pipe_add_arg(argv, &argc, SIGNAL_PIPE_CTRL_ID_NONE);
1148 return sync_pipe_run_command(argv, data, primary_msg, secondary_msg);
1152 * Get the capabilities of an interface using dumpcap.
1154 * On success, *data points to a buffer containing the dumpcap output,
1155 * *primary_msg and *secondary_msg are NULL, and 0 is returned. *data
1156 * must be freed with g_free().
1158 * On failure, *data is NULL, *primary_msg points to an error message,
1159 * *secondary_msg either points to an additional error message or is
1160 * NULL, and -1 is returned; *primary_msg, and *secondary_msg if not NULL,
1161 * must be freed with g_free().
1164 sync_if_capabilities_open(const gchar *ifname, gboolean monitor_mode,
1165 gchar **data, gchar **primary_msg,
1166 gchar **secondary_msg)
1171 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "sync_linktype_list_open");
1173 argv = init_pipe_args(&argc);
1176 *primary_msg = g_strdup("We don't know where to find dumpcap.");
1177 *secondary_msg = NULL;
1182 /* Ask for the interface capabilities */
1183 argv = sync_pipe_add_arg(argv, &argc, "-i");
1184 argv = sync_pipe_add_arg(argv, &argc, ifname);
1185 argv = sync_pipe_add_arg(argv, &argc, "-L");
1187 argv = sync_pipe_add_arg(argv, &argc, "-I");
1190 /* Run dumpcap in capture child mode */
1191 argv = sync_pipe_add_arg(argv, &argc, "-Z");
1192 argv = sync_pipe_add_arg(argv, &argc, SIGNAL_PIPE_CTRL_ID_NONE);
1194 return sync_pipe_run_command(argv, data, primary_msg, secondary_msg);
1198 * Start getting interface statistics using dumpcap. On success, read_fd
1199 * contains the file descriptor for the pipe's stdout, *msg is unchanged,
1200 * and zero is returned. On failure, *msg will point to an error message
1201 * that must be g_free()d, and -1 will be returned.
1204 sync_interface_stats_open(int *data_read_fd, int *fork_child, gchar **msg)
1208 int message_read_fd, ret;
1210 gchar buffer[PIPE_BUF_SIZE+1];
1213 int primary_msg_len;
1214 char *primary_msg_text;
1215 int secondary_msg_len;
1216 /*char *secondary_msg_text;*/
1219 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "sync_interface_stats_open");
1221 argv = init_pipe_args(&argc);
1224 *msg = g_strdup("We don't know where to find dumpcap.");
1228 /* Ask for the interface statistics */
1229 argv = sync_pipe_add_arg(argv, &argc, "-S");
1232 argv = sync_pipe_add_arg(argv, &argc, "-Z");
1233 argv = sync_pipe_add_arg(argv, &argc, SIGNAL_PIPE_CTRL_ID_NONE);
1235 ret = sync_pipe_open_command(argv, data_read_fd, &message_read_fd,
1241 * We were able to set up to read dumpcap's output. Do so.
1243 * First, wait for an SP_ERROR_MSG message or SP_SUCCESS message.
1245 nread = pipe_read_block(message_read_fd, &indicator, SP_MAX_MSG_LEN,
1248 /* We got a read error from the sync pipe, or we got no data at
1249 all from the sync pipe, so we're not going to be getting any
1250 data or error message from the child process. Pick up its
1251 exit status, and complain.
1253 We don't have to worry about killing the child, if the sync pipe
1254 returned an error. Usually this error is caused as the child killed
1255 itself while going down. Even in the rare cases that this isn't the
1256 case, the child will get an error when writing to the broken pipe
1257 the next time, cleaning itself up then. */
1258 ret = sync_pipe_wait_for_child(*fork_child, &wait_msg);
1260 /* We got an EOF from the sync pipe. That means that it exited
1261 before giving us any data to read. If ret is -1, we report
1262 that as a bad exit (e.g., exiting due to a signal); otherwise,
1263 we report it as a premature exit. */
1267 *msg = g_strdup("Child dumpcap closed sync pipe prematurely");
1269 /* We got an error from the sync pipe. If ret is -1, report
1270 both the sync pipe I/O error and the wait error. */
1272 combined_msg = g_strdup_printf("%s\n\n%s", *msg, wait_msg);
1275 *msg = combined_msg;
1282 /* we got a valid message block from the child, process it */
1287 * Error from dumpcap; there will be a primary message and a
1288 * secondary message.
1291 /* convert primary message */
1292 pipe_convert_header(buffer, 4, &indicator, &primary_msg_len);
1293 primary_msg_text = buffer+4;
1294 /* convert secondary message */
1295 pipe_convert_header(primary_msg_text + primary_msg_len, 4, &indicator,
1296 &secondary_msg_len);
1297 /*secondary_msg_text = primary_msg_text + primary_msg_len + 4;*/
1298 /* the capture child will close the sync_pipe, nothing to do */
1301 * Pick up the child status.
1303 ret = sync_pipe_close_command(data_read_fd, &message_read_fd,
1307 * Child process failed unexpectedly, or wait failed; msg is the
1312 * Child process failed, but returned the expected exit status.
1313 * Return the messages it gave us, and indicate failure.
1315 *msg = g_strdup(primary_msg_text);
1321 /* Close the message pipe. */
1322 ws_close(message_read_fd);
1327 * Pick up the child status.
1329 ret = sync_pipe_close_command(data_read_fd, &message_read_fd,
1333 * Child process failed unexpectedly, or wait failed; msg is the
1338 * Child process returned an unknown status.
1340 *msg = g_strdup_printf("dumpcap process gave an unexpected message type: 0x%02x",
1349 /* Close down the stats process */
1351 sync_interface_stats_close(int *read_fd, int *fork_child, gchar **msg)
1353 return sync_pipe_close_command(read_fd, NULL, fork_child, msg);
1356 /* read a number of bytes from a pipe */
1357 /* (blocks until enough bytes read or an error occurs) */
1359 pipe_read_bytes(int pipe_fd, char *bytes, int required, char **msg)
1366 newly = read(pipe_fd, &bytes[offset], required);
1369 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
1370 "read from pipe %d: EOF (capture closed?)", pipe_fd);
1377 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
1378 "read from pipe %d: error(%u): %s", pipe_fd, error,
1380 *msg = g_strdup_printf("Error reading from sync pipe: %s",
1393 static gboolean pipe_data_available(int pipe_fd) {
1394 #ifdef _WIN32 /* PeekNamedPipe */
1395 HANDLE hPipe = (HANDLE) _get_osfhandle(pipe_fd);
1398 if (hPipe == INVALID_HANDLE_VALUE)
1401 if (! PeekNamedPipe(hPipe, NULL, 0, NULL, &bytes_avail, NULL))
1404 if (bytes_avail > 0)
1409 struct timeval timeout;
1412 FD_SET(pipe_fd, &rfds);
1414 timeout.tv_usec = 0;
1416 if (select(pipe_fd+1, &rfds, NULL, NULL, &timeout) > 0)
1423 /* Read a line from a pipe, similar to fgets */
1425 sync_pipe_gets_nonblock(int pipe_fd, char *bytes, int max) {
1429 while(offset < max - 1) {
1431 if (! pipe_data_available(pipe_fd))
1433 newly = read(pipe_fd, &bytes[offset], 1);
1435 /* EOF - not necessarily an error */
1437 } else if (newly < 0) {
1439 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
1440 "read from pipe %d: error(%u): %s", pipe_fd, errno, g_strerror(errno));
1442 } else if (bytes[offset] == '\n') {
1448 bytes[offset] = '\0';
1454 /* convert header values (indicator and 3-byte length) */
1456 pipe_convert_header(const guchar *header, int header_len, char *indicator, int *block_len) {
1458 g_assert(header_len == 4);
1460 /* convert header values */
1461 *indicator = header[0];
1462 *block_len = header[1]<<16 | header[2]<<8 | header[3];
1465 /* read a message from the sending pipe in the standard format
1466 (1-byte message indicator, 3-byte message length (excluding length
1467 and indicator field), and the rest is the message) */
1469 pipe_read_block(int pipe_fd, char *indicator, int len, char *msg,
1476 /* read header (indicator and 3-byte length) */
1477 newly = pipe_read_bytes(pipe_fd, header, 4, err_msg);
1481 * Immediate EOF; if the capture child exits normally, this
1482 * is an "I'm done" indication, so don't report it as an
1485 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
1486 "read %d got an EOF", pipe_fd);
1489 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
1490 "read %d failed to read header: %u", pipe_fd, newly);
1493 * Short read, but not an immediate EOF.
1495 *err_msg = g_strdup_printf("Premature EOF reading from sync pipe: got only %d bytes",
1501 /* convert header values */
1502 pipe_convert_header(header, 4, indicator, &required);
1504 /* only indicator with no value? */
1506 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
1507 "read %d indicator: %c empty value", pipe_fd, *indicator);
1511 /* does the data fit into the given buffer? */
1512 if(required > len) {
1513 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
1514 "read %d length error, required %d > len %d, indicator: %u",
1515 pipe_fd, required, len, *indicator);
1517 /* we have a problem here, try to read some more bytes from the pipe to debug where the problem really is */
1518 memcpy(msg, header, sizeof(header));
1519 newly = read(pipe_fd, &msg[sizeof(header)], len-sizeof(header));
1520 *err_msg = g_strdup_printf("Unknown message from dumpcap, try to show it as a string: %s",
1526 /* read the actual block data */
1527 newly = pipe_read_bytes(pipe_fd, msg, required, err_msg);
1528 if(newly != required) {
1530 *err_msg = g_strdup_printf("Unknown message from dumpcap, try to show it as a string: %s",
1536 /* XXX If message is "2part", the msg probably won't be sent to debug log correctly */
1537 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
1538 "read %d ok indicator: %c len: %u msg: %s", pipe_fd, *indicator,
1545 /* There's stuff to read from the sync pipe, meaning the child has sent
1546 us a message, or the sync pipe has closed, meaning the child has
1547 closed it (perhaps because it exited). */
1549 sync_pipe_input_cb(gint source, gpointer user_data)
1551 capture_options *capture_opts = (capture_options *)user_data;
1553 char buffer[SP_MAX_MSG_LEN+1];
1559 char *secondary_msg;
1560 char *wait_msg, *combined_msg;
1562 nread = pipe_read_block(source, &indicator, SP_MAX_MSG_LEN, buffer,
1565 /* We got a read error, or a bad message, or an EOF, from the sync pipe.
1567 If we got a read error or a bad message, nread is -1 and
1568 primary_msg is set to point to an error message. We don't
1569 have to worry about killing the child; usually this error
1570 is caused as the child killed itself while going down.
1571 Even in the rare cases that this isn't the case, the child
1572 will get an error when writing to the broken pipe the next time,
1573 cleaning itself up then.
1575 If we got an EOF, nread is 0 and primary_msg isn't set. This
1576 is an indication that the capture is finished. */
1577 ret = sync_pipe_wait_for_child(capture_opts->fork_child, &wait_msg);
1579 /* We got an EOF from the sync pipe. That means that the capture
1580 child exited, and not in the middle of a message; we treat
1581 that as an indication that it's done, and only report an
1582 error if ret is -1, in which case wait_msg is the error
1585 primary_msg = wait_msg;
1587 /* We got an error from the sync pipe. If ret is -1, report
1588 both the sync pipe I/O error and the wait error. */
1590 combined_msg = g_strdup_printf("%s\n\n%s", primary_msg, wait_msg);
1591 g_free(primary_msg);
1593 primary_msg = combined_msg;
1597 /* No more child process. */
1598 capture_opts->fork_child = -1;
1599 capture_opts->fork_child_status = ret;
1602 ws_close(capture_opts->signal_pipe_write_fd);
1604 capture_input_closed(capture_opts, primary_msg);
1605 g_free(primary_msg);
1609 /* we got a valid message block from the child, process it */
1612 if(!capture_input_new_file(capture_opts, buffer)) {
1613 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "sync_pipe_input_cb: file failed, closing capture");
1615 /* We weren't able to open the new capture file; user has been
1616 alerted. Close the sync pipe. */
1619 /* The child has sent us a filename which we couldn't open.
1621 This could mean that the child is creating files faster
1622 than we can handle it. (XXX - why would that result in
1623 a failure to open the file?)
1625 That should only be the case for very fast file switches;
1626 We can't do much more than telling the child to stop.
1627 (This is the "emergency brake" if the user e.g. wants to
1628 switch files every second).
1630 This can also happen if the user specified "-", meaning
1631 "standard output", as the capture file. */
1632 sync_pipe_stop(capture_opts);
1633 capture_input_closed(capture_opts, NULL);
1637 case SP_PACKET_COUNT:
1638 nread = atoi(buffer);
1639 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "sync_pipe_input_cb: new packets %u", nread);
1640 capture_input_new_packets(capture_opts, nread);
1643 /* convert primary message */
1644 pipe_convert_header(buffer, 4, &indicator, &primary_len);
1645 primary_msg = buffer+4;
1646 /* convert secondary message */
1647 pipe_convert_header(primary_msg + primary_len, 4, &indicator, &secondary_len);
1648 secondary_msg = primary_msg + primary_len + 4;
1649 /* message output */
1650 capture_input_error_message(capture_opts, primary_msg, secondary_msg);
1651 /* the capture child will close the sync_pipe, nothing to do for now */
1652 /* (an error message doesn't mean we have to stop capturing) */
1654 case SP_BAD_FILTER: {
1658 ch = strtok(buffer, ":");
1659 index = (int)strtol(ch, NULL, 10);
1660 ch = strtok(NULL, ":");
1661 capture_input_cfilter_error_message(capture_opts, index, ch);
1662 /* the capture child will close the sync_pipe, nothing to do for now */
1666 capture_input_drops(capture_opts, (guint32)strtoul(buffer, NULL, 10));
1669 g_assert_not_reached();
1678 * dumpcap is exiting; wait for it to exit. On success, *msgp is
1679 * unchanged, and the exit status of dumpcap is returned. On
1680 * failure (which includes "dumpcap exited due to being killed by
1681 * a signal or an exception"), *msgp points to an error message
1682 * for the failure, and -1 is returned. In the latter case, *msgp
1683 * must be freed with g_free().
1686 sync_pipe_wait_for_child(int fork_child, gchar **msgp)
1688 int fork_child_status;
1691 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "sync_pipe_wait_for_child: wait till child closed");
1692 g_assert(fork_child != -1);
1694 *msgp = NULL; /* assume no error */
1696 if (_cwait(&fork_child_status, fork_child, _WAIT_CHILD) == -1) {
1697 *msgp = g_strdup_printf("Error from cwait(): %s", g_strerror(errno));
1701 * The child exited; return its exit status. Do not treat this as
1704 ret = fork_child_status;
1705 if ((fork_child_status & 0xC0000000) == ERROR_SEVERITY_ERROR) {
1706 /* Probably an exception code */
1707 *msgp = g_strdup_printf("Child dumpcap process died: %s",
1708 win32strexception(fork_child_status));
1713 if (waitpid(fork_child, &fork_child_status, 0) != -1) {
1714 if (WIFEXITED(fork_child_status)) {
1716 * The child exited; return its exit status. Do not treat this as
1719 ret = WEXITSTATUS(fork_child_status);
1720 } else if (WIFSTOPPED(fork_child_status)) {
1721 /* It stopped, rather than exiting. "Should not happen." */
1722 *msgp = g_strdup_printf("Child dumpcap process stopped: %s",
1723 sync_pipe_signame(WSTOPSIG(fork_child_status)));
1725 } else if (WIFSIGNALED(fork_child_status)) {
1726 /* It died with a signal. */
1727 *msgp = g_strdup_printf("Child dumpcap process died: %s%s",
1728 sync_pipe_signame(WTERMSIG(fork_child_status)),
1729 WCOREDUMP(fork_child_status) ? " - core dumped" : "");
1732 /* What? It had to either have exited, or stopped, or died with
1733 a signal; what happened here? */
1734 *msgp = g_strdup_printf("Bad status from waitpid(): %#o",
1739 *msgp = g_strdup_printf("Error from waitpid(): %s", g_strerror(errno));
1744 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "sync_pipe_wait_for_child: capture child closed");
1750 /* convert signal to corresponding name */
1752 sync_pipe_signame(int sig)
1755 static char sigmsg_buf[6+1+3+1];
1764 sigmsg = "Interrupted";
1772 sigmsg = "Illegal instruction";
1776 sigmsg = "Trace trap";
1784 sigmsg = "Arithmetic exception";
1792 sigmsg = "Bus error";
1796 sigmsg = "Segmentation violation";
1799 /* http://metalab.unc.edu/pub/Linux/docs/HOWTO/GCC-HOWTO
1800 Linux is POSIX compliant. These are not POSIX-defined signals ---
1801 ISO/IEC 9945-1:1990 (IEEE Std 1003.1-1990), paragraph B.3.3.1.1 sez:
1803 ``The signals SIGBUS, SIGEMT, SIGIOT, SIGTRAP, and SIGSYS
1804 were omitted from POSIX.1 because their behavior is
1805 implementation dependent and could not be adequately catego-
1806 rized. Conforming implementations may deliver these sig-
1807 nals, but must document the circumstances under which they
1808 are delivered and note any restrictions concerning their
1811 So we only check for SIGSYS on those systems that happen to
1812 implement them (a system can be POSIX-compliant and implement
1813 them, it's just that POSIX doesn't *require* a POSIX-compliant
1814 system to implement them).
1819 sigmsg = "Bad system call";
1824 sigmsg = "Broken pipe";
1828 sigmsg = "Alarm clock";
1832 sigmsg = "Terminated";
1836 /* Returning a static buffer is ok in the context we use it here */
1837 g_snprintf(sigmsg_buf, sizeof sigmsg_buf, "Signal %d", sig);
1838 sigmsg = sigmsg_buf;
1847 /* tell the child through the signal pipe that we want to quit the capture */
1849 signal_pipe_capquit_to_child(capture_options *capture_opts)
1851 const char quit_msg[] = "QUIT";
1855 g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "signal_pipe_capquit_to_child");
1857 /* it doesn't matter *what* we send here, the first byte will stop the capture */
1858 /* simply sending a "QUIT" string */
1859 /*pipe_write_block(capture_opts->signal_pipe_write_fd, SP_QUIT, quit_msg);*/
1860 ret = write(capture_opts->signal_pipe_write_fd, quit_msg, sizeof quit_msg);
1862 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_WARNING,
1863 "signal_pipe_capquit_to_child: %d header: error %s", capture_opts->signal_pipe_write_fd, g_strerror(errno));
1869 /* user wants to stop the capture run */
1871 sync_pipe_stop(capture_options *capture_opts)
1876 gboolean terminate = TRUE;
1879 if (capture_opts->fork_child != -1) {
1881 /* send the SIGINT signal to close the capture child gracefully. */
1882 int sts = kill(capture_opts->fork_child, SIGINT);
1884 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_WARNING,
1885 "Sending SIGINT to child failed: %s\n", g_strerror(errno));
1888 #define STOP_SLEEP_TIME 500 /* ms */
1889 #define STOP_CHECK_TIME 50
1890 /* First, use the special signal pipe to try to close the capture child
1893 signal_pipe_capquit_to_child(capture_opts);
1895 /* Next, wait for the process to exit on its own */
1896 for (count = 0; count < STOP_SLEEP_TIME / STOP_CHECK_TIME; count++) {
1897 if (GetExitCodeProcess((HANDLE) capture_opts->fork_child, &childstatus) &&
1898 childstatus != STILL_ACTIVE) {
1902 Sleep(STOP_CHECK_TIME);
1905 /* Force the issue. */
1907 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_WARNING,
1908 "sync_pipe_stop: forcing child to exit");
1909 sync_pipe_kill(capture_opts->fork_child);
1916 /* Wireshark has to exit, force the capture child to close */
1918 sync_pipe_kill(int fork_child)
1920 if (fork_child != -1) {
1922 int sts = kill(fork_child, SIGTERM); /* SIGTERM so it can clean up if necessary */
1924 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_WARNING,
1925 "Sending SIGTERM to child failed: %s\n", g_strerror(errno));
1928 /* Remark: This is not the preferred method of closing a process!
1929 * the clean way would be getting the process id of the child process,
1930 * then getting window handle hWnd of that process (using EnumChildWindows),
1931 * and then do a SendMessage(hWnd, WM_CLOSE, 0, 0)
1933 * Unfortunately, I don't know how to get the process id from the
1934 * handle. OpenProcess will get an handle (not a window handle)
1935 * from the process ID; it will not get a window handle from the
1936 * process ID. (How could it? A process can have more than one
1937 * window. For that matter, a process might have *no* windows,
1938 * as a process running dumpcap, the normal child process program,
1941 * Hint: GenerateConsoleCtrlEvent() will only work if both processes are
1942 * running in the same console; that's not necessarily the case for
1943 * us, as we might not be running in a console.
1944 * And this also will require to have the process id.
1946 TerminateProcess((HANDLE) (fork_child), 0);
1951 #endif /* HAVE_LIBPCAP */