2 * The actual capturing loop, getting packets and storing it
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.
28 * Capture loop (internal interface).
30 * It will open the input and output files, capture the packets,
31 * change ringbuffer output files while capturing and close all files again.
33 * The input file can be a network interface or capture pipe (unix only).
34 * The output file can be a single or a ringbuffer file handled by wiretap.
54 #ifdef HAVE_SYS_TYPES_H
55 # include <sys/types.h>
58 #ifdef HAVE_SYS_STAT_H
59 # include <sys/stat.h>
73 #include "capture-pcap-util.h"
76 #include "capture_sync.h"
78 #include "conditions.h"
79 #include "capture_stop_conditions.h"
80 #include "ringbuffer.h"
82 #include "simple_dialog.h"
85 #include "file_util.h"
87 #include "epan/unicode-utils.h"
89 #include "capture_loop.h"
92 * Standard secondary message for unexpected errors.
94 static const char please_report[] =
95 "Please report this to the Wireshark developers. (This is not a crash;\n"
96 "please do not report it as such.)";
99 * This needs to be static, so that the SIGUSR1 handler can clear the "go"
106 * Timeout, in milliseconds, for reads from the stream of captured packets.
108 #define CAP_READ_TIMEOUT 250
109 static char *cap_pipe_err_str;
111 static void capture_loop_packet_cb(u_char *user, const struct pcap_pkthdr *phdr,
113 static void capture_loop_get_errmsg(char *errmsg, int errmsglen, const char *fname,
114 int err, gboolean is_close);
118 /* Take care of byte order in the libpcap headers read from pipes.
119 * (function taken from wiretap/libpcap.c) */
121 cap_pipe_adjust_header(gboolean byte_swapped, struct pcap_hdr *hdr, struct pcaprec_hdr *rechdr)
124 /* Byte-swap the record header fields. */
125 rechdr->ts_sec = BSWAP32(rechdr->ts_sec);
126 rechdr->ts_usec = BSWAP32(rechdr->ts_usec);
127 rechdr->incl_len = BSWAP32(rechdr->incl_len);
128 rechdr->orig_len = BSWAP32(rechdr->orig_len);
131 /* In file format version 2.3, the "incl_len" and "orig_len" fields were
132 swapped, in order to match the BPF header layout.
134 Unfortunately, some files were, according to a comment in the "libpcap"
135 source, written with version 2.3 in their headers but without the
136 interchanged fields, so if "incl_len" is greater than "orig_len" - which
137 would make no sense - we assume that we need to swap them. */
138 if (hdr->version_major == 2 &&
139 (hdr->version_minor < 3 ||
140 (hdr->version_minor == 3 && rechdr->incl_len > rechdr->orig_len))) {
143 temp = rechdr->orig_len;
144 rechdr->orig_len = rechdr->incl_len;
145 rechdr->incl_len = temp;
149 /* Provide select() functionality for a single file descriptor
150 * on both UNIX/POSIX and Windows.
152 * The Windows version calls WaitForSingleObject instead of
155 * Returns the same values as select. If an error is returned,
156 * the string cap_pipe_err_str should be used instead of errno.
159 cap_pipe_select(int pipe_fd, gboolean wait_forever) {
162 struct timeval timeout, *pto;
165 cap_pipe_err_str = "Unknown error";
168 FD_SET(pipe_fd, &rfds);
173 timeout.tv_usec = CAP_READ_TIMEOUT * 1000;
176 sel_ret = select(pipe_fd+1, &rfds, NULL, NULL, pto);
178 cap_pipe_err_str = strerror(errno);
182 /* XXX - Should we just use file handles exclusively under Windows?
183 * Otherwise we have to convert between file handles and file descriptors
184 * here and when we open a named pipe.
186 HANDLE hPipe = (HANDLE) _get_osfhandle(pipe_fd);
188 DWORD timeout = wait_forever ? INFINITE : CAP_READ_TIMEOUT * 1000;
191 if (hPipe == INVALID_HANDLE_VALUE) {
192 cap_pipe_err_str = "Could not open standard input";
196 cap_pipe_err_str = "Unknown error";
198 wait_ret = WaitForSingleObject(hPipe, timeout);
200 /* XXX - This probably isn't correct */
209 FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_ALLOCATE_BUFFER,
210 NULL, GetLastError(), 0, (LPTSTR) &err_str, 0, NULL);
211 cap_pipe_err_str = utf_16to8(err_str);
215 g_assert_not_reached();
222 /* Mimic pcap_open_live() for pipe captures
223 * We check if "pipename" is "-" (stdin) or a FIFO, open it, and read the
225 * N.B. : we can't read the libpcap formats used in RedHat 6.1 or SuSE 6.3
226 * because we can't seek on pipes (see wiretap/libpcap.c for details) */
228 cap_pipe_open_live(char *pipename, struct pcap_hdr *hdr, loop_data *ld,
229 char *errmsg, int errmsgl)
232 struct stat pipe_stat;
244 unsigned int bytes_read;
246 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "cap_pipe_open_live: %s", pipename);
249 * XXX (T)Wireshark blocks until we return
251 if (strcmp(pipename, "-") == 0) {
252 fd = 0; /* read from stdin */
255 * This is needed to set the stdin pipe into binary mode, otherwise
256 * CR/LF are mangled...
258 _setmode(0, _O_BINARY);
262 if (eth_stat(pipename, &pipe_stat) < 0) {
263 if (errno == ENOENT || errno == ENOTDIR)
264 ld->cap_pipe_err = PIPNEXIST;
266 g_snprintf(errmsg, errmsgl,
267 "The capture session could not be initiated "
268 "due to error on pipe: %s", strerror(errno));
269 ld->cap_pipe_err = PIPERR;
273 if (! S_ISFIFO(pipe_stat.st_mode)) {
274 if (S_ISCHR(pipe_stat.st_mode)) {
276 * Assume the user specified an interface on a system where
277 * interfaces are in /dev. Pretend we haven't seen it.
279 ld->cap_pipe_err = PIPNEXIST;
282 g_snprintf(errmsg, errmsgl,
283 "The capture session could not be initiated because\n"
284 "\"%s\" is neither an interface nor a pipe", pipename);
285 ld->cap_pipe_err = PIPERR;
289 fd = eth_open(pipename, O_RDONLY | O_NONBLOCK, 0000 /* no creation so don't matter */);
291 g_snprintf(errmsg, errmsgl,
292 "The capture session could not be initiated "
293 "due to error on pipe open: %s", strerror(errno));
294 ld->cap_pipe_err = PIPERR;
298 #if 1 /* Enable/disable Windows named pipes */
299 #define PIPE_STR "\\pipe\\"
300 /* Under Windows, named pipes _must_ have the form
301 * "\\<server>\pipe\<pipename>". <server> may be "." for localhost.
303 pncopy = g_strdup(pipename);
304 if ( (pos=strstr(pncopy, "\\\\")) == pncopy) {
305 pos = strchr(pncopy + 3, '\\');
306 if (pos && g_strncasecmp(pos, PIPE_STR, strlen(PIPE_STR)) != 0)
313 g_snprintf(errmsg, errmsgl,
314 "The capture session could not be initiated because\n"
315 "\"%s\" is neither an interface nor a pipe", pipename);
316 ld->cap_pipe_err = PIPNEXIST;
320 /* Wait for the pipe to appear */
322 hPipe = CreateFile(utf_8to16(pipename), GENERIC_READ, 0, NULL,
323 OPEN_EXISTING, 0, NULL);
325 if (hPipe != INVALID_HANDLE_VALUE)
328 if (GetLastError() != ERROR_PIPE_BUSY) {
329 FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_ALLOCATE_BUFFER,
330 NULL, GetLastError(), 0, (LPTSTR) &err_str, 0, NULL);
331 g_snprintf(errmsg, errmsgl,
332 "The capture session on \"%s\" could not be initiated "
333 "due to error on pipe open: pipe busy: %s (error %d)",
334 pipename, utf_16to8(err_str), GetLastError());
336 ld->cap_pipe_err = PIPERR;
340 if (!WaitNamedPipe(utf_8to16(pipename), 30 * 1000)) {
341 FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_ALLOCATE_BUFFER,
342 NULL, GetLastError(), 0, (LPTSTR) &err_str, 0, NULL);
343 g_snprintf(errmsg, errmsgl,
344 "The capture session could not be initiated "
345 "due to error on pipe open: %s (error %d)",
346 utf_16to8(err_str), GetLastError());
348 ld->cap_pipe_err = PIPERR;
353 fd = _open_osfhandle((long) hPipe, _O_RDONLY);
355 g_snprintf(errmsg, errmsgl,
356 "The capture session could not be initiated "
357 "due to error on pipe open: %s", strerror(errno));
358 ld->cap_pipe_err = PIPERR;
361 #else /* Enable/disable Windows named pipes */
362 /* On Windows, we don't support capturing on pipes, so we give up. */
364 g_snprintf(errmsg, errmsgl,
365 "The capture session could not be initiated. Unable to open interface.");
366 ld->cap_pipe_err = PIPNEXIST;
368 #endif /* Enable/disable Windows named pipes */
372 ld->from_cap_pipe = TRUE;
374 /* read the pcap header */
376 while (bytes_read < sizeof magic) {
377 sel_ret = cap_pipe_select(fd, FALSE);
379 g_snprintf(errmsg, errmsgl,
380 "Unexpected error from select: %s", strerror(errno));
382 } else if (sel_ret > 0) {
383 b = read(fd, ((char *)&magic)+bytes_read, sizeof magic-bytes_read);
386 g_snprintf(errmsg, errmsgl, "End of file on pipe during open");
388 g_snprintf(errmsg, errmsgl, "Error on pipe during open: %s",
398 /* Host that wrote it has our byte order, and was running
399 a program using either standard or ss990417 libpcap. */
400 ld->cap_pipe_byte_swapped = FALSE;
401 ld->cap_pipe_modified = FALSE;
403 case PCAP_MODIFIED_MAGIC:
404 /* Host that wrote it has our byte order, but was running
405 a program using either ss990915 or ss991029 libpcap. */
406 ld->cap_pipe_byte_swapped = FALSE;
407 ld->cap_pipe_modified = TRUE;
409 case PCAP_SWAPPED_MAGIC:
410 /* Host that wrote it has a byte order opposite to ours,
411 and was running a program using either standard or
413 ld->cap_pipe_byte_swapped = TRUE;
414 ld->cap_pipe_modified = FALSE;
416 case PCAP_SWAPPED_MODIFIED_MAGIC:
417 /* Host that wrote it out has a byte order opposite to
418 ours, and was running a program using either ss990915
419 or ss991029 libpcap. */
420 ld->cap_pipe_byte_swapped = TRUE;
421 ld->cap_pipe_modified = TRUE;
424 /* Not a "libpcap" type we know about. */
425 g_snprintf(errmsg, errmsgl, "Unrecognized libpcap format");
429 /* Read the rest of the header */
431 while (bytes_read < sizeof(struct pcap_hdr)) {
432 sel_ret = cap_pipe_select(fd, FALSE);
434 g_snprintf(errmsg, errmsgl,
435 "Unexpected error from select: %s", strerror(errno));
437 } else if (sel_ret > 0) {
438 b = read(fd, ((char *)hdr)+bytes_read,
439 sizeof(struct pcap_hdr) - bytes_read);
442 g_snprintf(errmsg, errmsgl, "End of file on pipe during open");
444 g_snprintf(errmsg, errmsgl, "Error on pipe during open: %s",
452 if (ld->cap_pipe_byte_swapped) {
453 /* Byte-swap the header fields about which we care. */
454 hdr->version_major = BSWAP16(hdr->version_major);
455 hdr->version_minor = BSWAP16(hdr->version_minor);
456 hdr->snaplen = BSWAP32(hdr->snaplen);
457 hdr->network = BSWAP32(hdr->network);
459 ld->linktype = hdr->network;
461 if (hdr->version_major < 2) {
462 g_snprintf(errmsg, errmsgl, "Unable to read old libpcap format");
466 ld->cap_pipe_state = STATE_EXPECT_REC_HDR;
467 ld->cap_pipe_err = PIPOK;
471 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "cap_pipe_open_live: error %s", errmsg);
472 ld->cap_pipe_err = PIPERR;
479 /* We read one record from the pipe, take care of byte order in the record
480 * header, write the record to the capture file, and update capture statistics. */
482 cap_pipe_dispatch(loop_data *ld, guchar *data, char *errmsg, int errmsgl)
484 struct pcap_pkthdr phdr;
486 enum { PD_REC_HDR_READ, PD_DATA_READ, PD_PIPE_EOF, PD_PIPE_ERR,
490 #ifdef LOG_CAPTURE_VERBOSE
491 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "cap_pipe_dispatch");
494 switch (ld->cap_pipe_state) {
496 case STATE_EXPECT_REC_HDR:
497 ld->cap_pipe_bytes_to_read = ld->cap_pipe_modified ?
498 sizeof(struct pcaprec_modified_hdr) : sizeof(struct pcaprec_hdr);
499 ld->cap_pipe_bytes_read = 0;
500 ld->cap_pipe_state = STATE_READ_REC_HDR;
503 case STATE_READ_REC_HDR:
504 b = read(ld->cap_pipe_fd, ((char *)&ld->cap_pipe_rechdr)+ld->cap_pipe_bytes_read,
505 ld->cap_pipe_bytes_to_read - ld->cap_pipe_bytes_read);
508 result = PD_PIPE_EOF;
510 result = PD_PIPE_ERR;
513 if ((ld->cap_pipe_bytes_read += b) < ld->cap_pipe_bytes_to_read)
515 result = PD_REC_HDR_READ;
518 case STATE_EXPECT_DATA:
519 ld->cap_pipe_bytes_read = 0;
520 ld->cap_pipe_state = STATE_READ_DATA;
523 case STATE_READ_DATA:
524 b = read(ld->cap_pipe_fd, data+ld->cap_pipe_bytes_read,
525 ld->cap_pipe_rechdr.hdr.incl_len - ld->cap_pipe_bytes_read);
528 result = PD_PIPE_EOF;
530 result = PD_PIPE_ERR;
533 if ((ld->cap_pipe_bytes_read += b) < ld->cap_pipe_rechdr.hdr.incl_len)
535 result = PD_DATA_READ;
539 g_snprintf(errmsg, errmsgl, "cap_pipe_dispatch: invalid state");
542 } /* switch (ld->cap_pipe_state) */
545 * We've now read as much data as we were expecting, so process it.
549 case PD_REC_HDR_READ:
550 /* We've read the header. Take care of byte order. */
551 cap_pipe_adjust_header(ld->cap_pipe_byte_swapped, &ld->cap_pipe_hdr,
552 &ld->cap_pipe_rechdr.hdr);
553 if (ld->cap_pipe_rechdr.hdr.incl_len > WTAP_MAX_PACKET_SIZE) {
554 g_snprintf(errmsg, errmsgl, "Frame %u too long (%d bytes)",
555 ld->packet_count+1, ld->cap_pipe_rechdr.hdr.incl_len);
558 ld->cap_pipe_state = STATE_EXPECT_DATA;
562 /* Fill in a "struct pcap_pkthdr", and process the packet. */
563 phdr.ts.tv_sec = ld->cap_pipe_rechdr.hdr.ts_sec;
564 phdr.ts.tv_usec = ld->cap_pipe_rechdr.hdr.ts_usec;
565 phdr.caplen = ld->cap_pipe_rechdr.hdr.incl_len;
566 phdr.len = ld->cap_pipe_rechdr.hdr.orig_len;
568 ld->packet_cb((u_char *)ld, &phdr, data);
570 ld->cap_pipe_state = STATE_EXPECT_REC_HDR;
574 ld->cap_pipe_err = PIPEOF;
578 g_snprintf(errmsg, errmsgl, "Error reading from pipe: %s",
585 ld->cap_pipe_err = PIPERR;
586 /* Return here rather than inside the switch to prevent GCC warning */
591 /* open the capture input file (pcap or capture pipe) */
593 capture_loop_open_input(capture_options *capture_opts, loop_data *ld,
594 char *errmsg, size_t errmsg_len,
595 char *secondary_errmsg, size_t secondary_errmsg_len)
597 gchar open_err_str[PCAP_ERRBUF_SIZE];
599 static const char ppamsg[] = "can't find PPA for ";
600 const char *set_linktype_err_str;
601 const char *libpcap_warn;
603 gchar *sync_secondary_msg_str;
605 WORD wVersionRequested;
610 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "capture_loop_open_input : %s", capture_opts->iface);
613 /* XXX - opening Winsock on tshark? */
615 /* Initialize Windows Socket if we are in a WIN32 OS
616 This needs to be done before querying the interface for network/netmask */
618 /* XXX - do we really require 1.1 or earlier?
619 Are there any versions that support only 2.0 or higher? */
620 wVersionRequested = MAKEWORD(1, 1);
621 err = WSAStartup(wVersionRequested, &wsaData);
626 g_snprintf(errmsg, errmsg_len,
627 "Couldn't initialize Windows Sockets: Network system not ready for network communication");
630 case WSAVERNOTSUPPORTED:
631 g_snprintf(errmsg, errmsg_len,
632 "Couldn't initialize Windows Sockets: Windows Sockets version %u.%u not supported",
633 LOBYTE(wVersionRequested), HIBYTE(wVersionRequested));
637 g_snprintf(errmsg, errmsg_len,
638 "Couldn't initialize Windows Sockets: Blocking operation is in progress");
642 g_snprintf(errmsg, errmsg_len,
643 "Couldn't initialize Windows Sockets: Limit on the number of tasks supported by this WinSock implementation has been reached");
647 g_snprintf(errmsg, errmsg_len,
648 "Couldn't initialize Windows Sockets: Bad pointer passed to WSAStartup");
652 g_snprintf(errmsg, errmsg_len,
653 "Couldn't initialize Windows Sockets: error %d", err);
656 g_snprintf(secondary_errmsg, secondary_errmsg_len, please_report);
661 /* Open the network interface to capture from it.
662 Some versions of libpcap may put warnings into the error buffer
663 if they succeed; to tell if that's happened, we have to clear
664 the error buffer, and check if it's still a null string. */
665 open_err_str[0] = '\0';
666 ld->pcap_h = pcap_open_live(capture_opts->iface,
667 capture_opts->has_snaplen ? capture_opts->snaplen :
668 WTAP_MAX_PACKET_SIZE,
669 capture_opts->promisc_mode, CAP_READ_TIMEOUT,
672 if (ld->pcap_h != NULL) {
673 /* we've opened "iface" as a network device */
675 /* try to set the capture buffer size */
676 if (pcap_setbuff(ld->pcap_h, capture_opts->buffer_size * 1024 * 1024) != 0) {
677 sync_secondary_msg_str = g_strdup_printf(
678 "The capture buffer size of %luMB seems to be too high for your machine,\n"
679 "the default of 1MB will be used.\n"
681 "Nonetheless, the capture is started.\n",
682 capture_opts->buffer_size);
683 report_capture_error("Couldn't set the capture buffer size!",
684 sync_secondary_msg_str);
685 g_free(sync_secondary_msg_str);
689 /* setting the data link type only works on real interfaces */
690 if (capture_opts->linktype != -1) {
691 set_linktype_err_str = set_pcap_linktype(ld->pcap_h, capture_opts->iface,
692 capture_opts->linktype);
693 if (set_linktype_err_str != NULL) {
694 g_snprintf(errmsg, errmsg_len, "Unable to set data link type (%s).",
695 set_linktype_err_str);
696 g_snprintf(secondary_errmsg, secondary_errmsg_len, please_report);
700 ld->linktype = get_pcap_linktype(ld->pcap_h, capture_opts->iface);
702 /* We couldn't open "iface" as a network device. */
703 /* Try to open it as a pipe */
704 ld->cap_pipe_fd = cap_pipe_open_live(capture_opts->iface, &ld->cap_pipe_hdr, ld, errmsg, errmsg_len);
706 if (ld->cap_pipe_fd == -1) {
708 if (ld->cap_pipe_err == PIPNEXIST) {
709 /* Pipe doesn't exist, so output message for interface */
711 /* If we got a "can't find PPA for X" message, warn the user (who
712 is running (T)Wireshark on HP-UX) that they don't have a version
713 of libpcap that properly handles HP-UX (libpcap 0.6.x and later
714 versions, which properly handle HP-UX, say "can't find /dev/dlpi
715 PPA for X" rather than "can't find PPA for X"). */
716 if (strncmp(open_err_str, ppamsg, sizeof ppamsg - 1) == 0)
719 "You are running (T)Wireshark with a version of the libpcap library\n"
720 "that doesn't handle HP-UX network devices well; this means that\n"
721 "(T)Wireshark may not be able to capture packets.\n"
723 "To fix this, you should install libpcap 0.6.2, or a later version\n"
724 "of libpcap, rather than libpcap 0.4 or 0.5.x. It is available in\n"
725 "packaged binary form from the Software Porting And Archive Centre\n"
726 "for HP-UX; the Centre is at http://hpux.connect.org.uk/ - the page\n"
727 "at the URL lists a number of mirror sites.";
730 g_snprintf(errmsg, errmsg_len,
731 "The capture session could not be initiated (%s).", open_err_str);
733 g_snprintf(secondary_errmsg, secondary_errmsg_len,
734 "Please check to make sure you have sufficient permissions, and that you have "
735 "the proper interface or pipe specified.%s", libpcap_warn);
737 g_snprintf(secondary_errmsg, secondary_errmsg_len,
739 "Please check that \"%s\" is the proper interface.\n"
742 "Help can be found at:\n"
744 " http://wiki.wireshark.org/CaptureSetup\n"
747 "WinPcap does not support 64-bit Windows; you will have to use some other\n"
748 "tool to capture traffic, such as netcap.\n"
749 "For netcap details see: http://support.microsoft.com/?id=310875\n"
752 "Note that version 3.0 of WinPcap, and earlier versions of WinPcap, don't\n"
753 "support capturing on PPP/WAN interfaces on Windows NT 4.0 / 2000 / XP /\n"
755 "WinPcap 3.1 has support for it on Windows 2000 / XP / Server 2003, but has no\n"
756 "support for it on Windows NT 4.0 or Windows Vista (Beta 1).",
757 capture_opts->iface);
761 * Else pipe (or file) does exist and cap_pipe_open_live() has
766 /* cap_pipe_open_live() succeeded; don't want
767 error message from pcap_open_live() */
768 open_err_str[0] = '\0';
771 /* XXX - will this work for tshark? */
772 #ifdef MUST_DO_SELECT
773 if (!ld->from_cap_pipe) {
774 #ifdef HAVE_PCAP_GET_SELECTABLE_FD
775 ld->pcap_fd = pcap_get_selectable_fd(ld->pcap_h);
777 ld->pcap_fd = pcap_fileno(ld->pcap_h);
782 /* Does "open_err_str" contain a non-empty string? If so, "pcap_open_live()"
783 returned a warning; print it, but keep capturing. */
784 if (open_err_str[0] != '\0') {
785 sync_msg_str = g_strdup_printf("%s.", open_err_str);
786 report_capture_error(sync_msg_str, "");
787 g_free(sync_msg_str);
794 /* close the capture input file (pcap or capture pipe) */
795 static void capture_loop_close_input(loop_data *ld) {
797 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "capture_loop_close_input");
799 /* if open, close the capture pipe "input file" */
800 if (ld->cap_pipe_fd >= 0) {
801 g_assert(ld->from_cap_pipe);
802 eth_close(ld->cap_pipe_fd);
806 /* if open, close the pcap "input file" */
807 if(ld->pcap_h != NULL) {
808 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "capture_loop_close_input: closing %p", ld->pcap_h);
809 g_assert(!ld->from_cap_pipe);
810 pcap_close(ld->pcap_h);
817 /* Shut down windows sockets */
823 /* init the capture filter */
824 initfilter_status_t capture_loop_init_filter(pcap_t *pcap_h, gboolean from_cap_pipe, gchar * iface, gchar * cfilter) {
825 bpf_u_int32 netnum, netmask;
826 gchar lookup_net_err_str[PCAP_ERRBUF_SIZE];
827 struct bpf_program fcode;
830 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "capture_loop_init_filter: %s", cfilter);
832 /* capture filters only work on real interfaces */
833 if (cfilter && !from_cap_pipe) {
834 /* A capture filter was specified; set it up. */
835 if (pcap_lookupnet(iface, &netnum, &netmask, lookup_net_err_str) < 0) {
837 * Well, we can't get the netmask for this interface; it's used
838 * only for filters that check for broadcast IP addresses, so
839 * we just punt and use 0. It might be nice to warn the user,
840 * but that's a pain in a GUI application, as it'd involve popping
841 * up a message box, and it's not clear how often this would make
842 * a difference (only filters that check for IP broadcast addresses
846 "Warning: Couldn't obtain netmask info (%s).", lookup_net_err_str);*/
849 if (pcap_compile(pcap_h, &fcode, cfilter, 1, netmask) < 0) {
850 /* Treat this specially - our caller might try to compile this
851 as a display filter and, if that succeeds, warn the user that
852 the display and capture filter syntaxes are different. */
853 return INITFILTER_BAD_FILTER;
855 if (pcap_setfilter(pcap_h, &fcode) < 0) {
856 #ifdef HAVE_PCAP_FREECODE
857 pcap_freecode(&fcode);
859 return INITFILTER_OTHER_ERROR;
861 #ifdef HAVE_PCAP_FREECODE
862 pcap_freecode(&fcode);
866 return INITFILTER_NO_ERROR;
870 /* set up to write to the already-opened capture output file/files */
871 gboolean capture_loop_init_output(capture_options *capture_opts, int save_file_fd, loop_data *ld, char *errmsg, int errmsg_len) {
876 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "capture_loop_init_output");
879 if (ld->from_cap_pipe) {
880 file_snaplen = ld->cap_pipe_hdr.snaplen;
883 file_snaplen = pcap_snapshot(ld->pcap_h);
886 /* Set up to write to the capture file. */
887 if (capture_opts->multi_files_on) {
888 ld->pdh = ringbuf_init_libpcap_fdopen(ld->linktype, file_snaplen,
889 &ld->bytes_written, &err);
891 ld->pdh = libpcap_fdopen(save_file_fd, ld->linktype, file_snaplen,
892 &ld->bytes_written, &err);
895 if (ld->pdh == NULL) {
896 /* We couldn't set up to write to the capture file. */
897 /* XXX - use cf_open_error_message from tshark instead? */
900 case WTAP_ERR_CANT_OPEN:
901 strcpy(errmsg, "The file to which the capture would be saved"
902 " couldn't be created for some unknown reason.");
905 case WTAP_ERR_SHORT_WRITE:
906 strcpy(errmsg, "A full header couldn't be written to the file"
907 " to which the capture would be saved.");
912 g_snprintf(errmsg, errmsg_len,
913 "The file to which the capture would be"
914 " saved (\"%s\") could not be opened: Error %d.",
915 capture_opts->save_file, err);
917 g_snprintf(errmsg, errmsg_len,
918 "The file to which the capture would be"
919 " saved (\"%s\") could not be opened: %s.",
920 capture_opts->save_file, strerror(err));
931 gboolean capture_loop_close_output(capture_options *capture_opts, loop_data *ld, int *err_close) {
933 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "capture_loop_close_output");
935 if (capture_opts->multi_files_on) {
936 return ringbuf_libpcap_dump_close(&capture_opts->save_file, err_close);
938 return libpcap_dump_close(ld->pdh, err_close);
942 /* dispatch incoming packets (pcap or capture pipe)
944 * Waits for incoming packets to be available, and calls pcap_dispatch()
945 * to cause them to be processed.
947 * Returns the number of packets which were dispatched.
949 * Times out (returning zero) after CAP_READ_TIMEOUT ms; this ensures that the
950 * packet-batching behaviour does not cause packets to get held back
954 capture_loop_dispatch(capture_options *capture_opts _U_, loop_data *ld,
955 char *errmsg, int errmsg_len) {
958 guchar pcap_data[WTAP_MAX_PACKET_SIZE];
960 if (ld->from_cap_pipe) {
961 /* dispatch from capture pipe */
962 #ifdef LOG_CAPTURE_VERBOSE
963 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "capture_loop_dispatch: from capture pipe");
965 sel_ret = cap_pipe_select(ld->cap_pipe_fd, FALSE);
968 if (sel_ret < 0 && errno != EINTR) {
969 g_snprintf(errmsg, errmsg_len,
970 "Unexpected error from select: %s", strerror(errno));
971 report_capture_error(errmsg, please_report);
976 * "select()" says we can read from the pipe without blocking
978 inpkts = cap_pipe_dispatch(ld, pcap_data, errmsg, errmsg_len);
986 /* dispatch from pcap */
987 #ifdef MUST_DO_SELECT
989 * If we have "pcap_get_selectable_fd()", we use it to get the
990 * descriptor on which to select; if that's -1, it means there
991 * is no descriptor on which you can do a "select()" (perhaps
992 * because you're capturing on a special device, and that device's
993 * driver unfortunately doesn't support "select()", in which case
994 * we don't do the select - which means it might not be possible
995 * to stop a capture until a packet arrives. If that's unacceptable,
996 * plead with whoever supplies the software for that device to add
997 * "select()" support, or upgrade to libpcap 0.8.1 or later, and
998 * rebuild Wireshark or get a version built with libpcap 0.8.1 or
999 * later, so it can use pcap_breakloop().
1001 #ifdef LOG_CAPTURE_VERBOSE
1002 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "capture_loop_dispatch: from pcap_dispatch with select");
1004 if (ld->pcap_fd != -1) {
1005 sel_ret = cap_pipe_select(ld->pcap_fd, FALSE);
1008 * "select()" says we can read from it without blocking; go for
1011 * We don't have pcap_breakloop(), so we only process one packet
1012 * per pcap_dispatch() call, to allow a signal to stop the
1013 * processing immediately, rather than processing all packets
1014 * in a batch before quitting.
1016 inpkts = pcap_dispatch(ld->pcap_h, 1, ld->packet_cb, (u_char *)ld);
1018 ld->pcap_err = TRUE;
1019 ld->go = FALSE; /* error or pcap_breakloop() - stop capturing */
1023 if (sel_ret < 0 && errno != EINTR) {
1024 g_snprintf(errmsg, errmsg_len,
1025 "Unexpected error from select: %s", strerror(errno));
1026 report_capture_error(errmsg, please_report);
1032 #endif /* MUST_DO_SELECT */
1034 /* dispatch from pcap without select */
1036 #ifdef LOG_CAPTURE_VERBOSE
1037 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "capture_loop_dispatch: from pcap_dispatch");
1041 * On Windows, we don't support asynchronously telling a process to
1042 * stop capturing; instead, we check for an indication on a pipe
1043 * after processing packets. We therefore process only one packet
1044 * at a time, so that we can check the pipe after every packet.
1046 inpkts = pcap_dispatch(ld->pcap_h, 1, ld->packet_cb, (u_char *) ld);
1048 inpkts = pcap_dispatch(ld->pcap_h, -1, ld->packet_cb, (u_char *) ld);
1052 /* Error, rather than pcap_breakloop(). */
1053 ld->pcap_err = TRUE;
1055 ld->go = FALSE; /* error or pcap_breakloop() - stop capturing */
1057 #else /* pcap_next_ex */
1058 #ifdef LOG_CAPTURE_VERBOSE
1059 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "capture_loop_dispatch: from pcap_next_ex");
1061 /* XXX - this is currently unused, as there is some confusion with pcap_next_ex() vs. pcap_dispatch() */
1064 * WinPcap's remote capturing feature doesn't work with pcap_dispatch(),
1065 * see http://wiki.wireshark.org/CaptureSetup_2fWinPcapRemote
1066 * This should be fixed in the WinPcap 4.0 alpha release.
1068 * For reference, an example remote interface:
1069 * rpcap://[1.2.3.4]/\Device\NPF_{39993D68-7C9B-4439-A329-F2D888DA7C5C}
1072 /* emulate dispatch from pcap */
1075 struct pcap_pkthdr *pkt_header;
1081 (in = pcap_next_ex(ld->pcap_h, &pkt_header, &pkt_data)) == 1) {
1082 ld->packet_cb( (u_char *) ld, pkt_header, pkt_data);
1087 ld->pcap_err = TRUE;
1092 #endif /* pcap_next_ex */
1096 #ifdef LOG_CAPTURE_VERBOSE
1097 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "capture_loop_dispatch: %d new packet%s", inpkts, plurality(inpkts, "", "s"));
1104 /* open the output file (temporary/specified name/ringbuffer/named pipe/stdout) */
1105 /* Returns TRUE if the file opened successfully, FALSE otherwise. */
1107 capture_loop_open_output(capture_options *capture_opts, int *save_file_fd,
1108 char *errmsg, int errmsg_len) {
1110 char tmpname[128+1];
1111 gchar *capfile_name;
1112 gboolean is_tempfile;
1115 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, "capture_loop_open_output: %s",
1116 (capture_opts->save_file) ? capture_opts->save_file : "");
1118 if (capture_opts->save_file != NULL) {
1119 /* We return to the caller while the capture is in progress.
1120 * Therefore we need to take a copy of save_file in
1121 * case the caller destroys it after we return.
1123 capfile_name = g_strdup(capture_opts->save_file);
1125 if (capture_opts->output_to_pipe == TRUE) { /* either "-" or named pipe */
1126 if (capture_opts->multi_files_on) {
1127 /* ringbuffer is enabled; that doesn't work with standard output or a named pipe */
1128 g_snprintf(errmsg, errmsg_len,
1129 "Ring buffer requested, but capture is being written to standard output or to a named pipe.");
1130 g_free(capfile_name);
1133 if (strcmp(capfile_name, "-") == 0) {
1134 /* write to stdout */
1137 /* set output pipe to binary mode to avoid Windows text-mode processing (eg: for CR/LF) */
1138 _setmode(1, O_BINARY);
1141 } /* if (...output_to_pipe ... */
1144 if (capture_opts->multi_files_on) {
1145 /* ringbuffer is enabled */
1146 *save_file_fd = ringbuf_init(capfile_name,
1147 (capture_opts->has_ring_num_files) ? capture_opts->ring_num_files : 0);
1149 /* we need the ringbuf name */
1150 if(*save_file_fd != -1) {
1151 g_free(capfile_name);
1152 capfile_name = g_strdup(ringbuf_current_filename());
1155 /* Try to open/create the specified file for use as a capture buffer. */
1156 *save_file_fd = open(capfile_name, O_RDWR|O_BINARY|O_TRUNC|O_CREAT,
1160 is_tempfile = FALSE;
1162 /* Choose a random name for the temporary capture buffer */
1163 *save_file_fd = create_tempfile(tmpname, sizeof tmpname, "ether");
1164 capfile_name = g_strdup(tmpname);
1168 /* did we fail to open the output file? */
1169 if (*save_file_fd == -1) {
1171 g_snprintf(errmsg, errmsg_len,
1172 "The temporary file to which the capture would be saved (\"%s\") "
1173 "could not be opened: %s.", capfile_name, strerror(errno));
1175 if (capture_opts->multi_files_on) {
1176 ringbuf_error_cleanup();
1179 g_snprintf(errmsg, errmsg_len,
1180 "The file to which the capture would be saved (\"%s\") "
1181 "could not be opened: %s.", capfile_name,
1184 g_free(capfile_name);
1188 if(capture_opts->save_file != NULL) {
1189 g_free(capture_opts->save_file);
1191 capture_opts->save_file = capfile_name;
1192 /* capture_opts.save_file is "g_free"ed later, which is equivalent to
1193 "g_free(capfile_name)". */
1195 fchown(*save_file_fd, capture_opts->owner, capture_opts->group);
1203 capture_loop_stop_signal_handler(int signo _U_)
1205 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_INFO, "Signal: Stop capture");
1206 capture_loop_stop();
1210 #define TIME_GET() GetTickCount()
1212 #define TIME_GET() time(NULL)
1215 /* Do the low-level work of a capture.
1216 Returns TRUE if it succeeds, FALSE otherwise. */
1218 capture_loop_start(capture_options *capture_opts, gboolean *stats_known, struct pcap_stat *stats)
1221 struct sigaction act;
1223 time_t upd_time, cur_time;
1227 gint inpkts_to_sync_pipe = 0; /* packets not already send out to the sync_pipe */
1228 condition *cnd_file_duration = NULL;
1229 condition *cnd_autostop_files = NULL;
1230 condition *cnd_autostop_size = NULL;
1231 condition *cnd_autostop_duration = NULL;
1232 guint32 autostop_files = 0;
1235 gboolean cfilter_error = FALSE;
1236 #define MSG_MAX_LENGTH 4096
1237 char errmsg[MSG_MAX_LENGTH+1];
1238 char secondary_errmsg[MSG_MAX_LENGTH+1];
1239 int save_file_fd = -1;
1242 *secondary_errmsg = '\0';
1244 /* init the loop data */
1246 ld.packet_count = 0;
1247 if (capture_opts->has_autostop_packets)
1248 ld.packet_max = capture_opts->autostop_packets;
1250 ld.packet_max = 0; /* no limit */
1251 ld.err = 0; /* no error seen yet */
1252 ld.wtap_linktype = WTAP_ENCAP_UNKNOWN;
1253 ld.pcap_err = FALSE;
1254 ld.from_cap_pipe = FALSE;
1256 ld.cap_pipe_fd = -1;
1257 #ifdef MUST_DO_SELECT
1260 ld.packet_cb = capture_loop_packet_cb;
1263 /* We haven't yet gotten the capture statistics. */
1264 *stats_known = FALSE;
1268 * Catch SIGUSR1, so that we exit cleanly if the parent process
1269 * kills us with it due to the user selecting "Capture->Stop".
1271 act.sa_handler = capture_loop_stop_signal_handler;
1273 * Arrange that system calls not get restarted, because when
1274 * our signal handler returns we don't want to restart
1275 * a call that was waiting for packets to arrive.
1278 sigemptyset(&act.sa_mask);
1279 sigaction(SIGUSR1, &act, NULL);
1282 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_INFO, "Capture loop starting ...");
1283 capture_opts_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_DEBUG, capture_opts);
1285 /* open the "input file" from network interface or capture pipe */
1286 if (!capture_loop_open_input(capture_opts, &ld, errmsg, sizeof(errmsg),
1287 secondary_errmsg, sizeof(secondary_errmsg))) {
1291 /* init the input filter from the network interface (capture pipe will do nothing) */
1292 switch (capture_loop_init_filter(ld.pcap_h, ld.from_cap_pipe, capture_opts->iface, capture_opts->cfilter)) {
1294 case INITFILTER_NO_ERROR:
1297 case INITFILTER_BAD_FILTER:
1298 cfilter_error = TRUE;
1299 g_snprintf(errmsg, sizeof(errmsg), "%s", pcap_geterr(ld.pcap_h));
1302 case INITFILTER_OTHER_ERROR:
1303 g_snprintf(errmsg, sizeof(errmsg), "Can't install filter (%s).",
1304 pcap_geterr(ld.pcap_h));
1305 g_snprintf(secondary_errmsg, sizeof(secondary_errmsg), "%s", please_report);
1309 /* If we're supposed to write to a capture file, open it for output
1310 (temporary/specified name/ringbuffer) */
1311 if (capture_opts->saving_to_file) {
1312 if (!capture_loop_open_output(capture_opts, &save_file_fd, errmsg, sizeof(errmsg))) {
1316 /* set up to write to the already-opened capture output file/files */
1317 if (!capture_loop_init_output(capture_opts, save_file_fd, &ld, errmsg, sizeof(errmsg))) {
1321 /* XXX - capture SIGTERM and close the capture, in case we're on a
1322 Linux 2.0[.x] system and you have to explicitly close the capture
1323 stream in order to turn promiscuous mode off? We need to do that
1324 in other places as well - and I don't think that works all the
1325 time in any case, due to libpcap bugs. */
1327 /* Well, we should be able to start capturing.
1329 Sync out the capture file, so the header makes it to the file system,
1330 and send a "capture started successfully and capture file created"
1331 message to our parent so that they'll open the capture file and
1332 update its windows to indicate that we have a live capture in
1334 libpcap_dump_flush(ld.pdh, NULL);
1335 report_new_capture_file(capture_opts->save_file);
1338 /* initialize capture stop (and alike) conditions */
1339 init_capture_stop_conditions();
1340 /* create stop conditions */
1341 if (capture_opts->has_autostop_filesize)
1343 cnd_new(CND_CLASS_CAPTURESIZE,(long)capture_opts->autostop_filesize * 1024);
1344 if (capture_opts->has_autostop_duration)
1345 cnd_autostop_duration =
1346 cnd_new(CND_CLASS_TIMEOUT,(gint32)capture_opts->autostop_duration);
1348 if (capture_opts->multi_files_on) {
1349 if (capture_opts->has_file_duration)
1351 cnd_new(CND_CLASS_TIMEOUT, capture_opts->file_duration);
1353 if (capture_opts->has_autostop_files)
1354 cnd_autostop_files =
1355 cnd_new(CND_CLASS_CAPTURESIZE, capture_opts->autostop_files);
1358 /* init the time values */
1359 start_time = TIME_GET();
1360 upd_time = TIME_GET();
1362 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_INFO, "Capture loop running!");
1364 /* WOW, everything is prepared! */
1365 /* please fasten your seat belts, we will enter now the actual capture loop */
1367 /* dispatch incoming packets */
1368 inpkts = capture_loop_dispatch(capture_opts, &ld, errmsg, sizeof(errmsg));
1371 /* any news from our parent (signal pipe)? -> just stop the capture */
1372 if (!signal_pipe_check_running()) {
1378 inpkts_to_sync_pipe += inpkts;
1380 /* check capture size condition */
1381 if (cnd_autostop_size != NULL &&
1382 cnd_eval(cnd_autostop_size, (guint32)ld.bytes_written)){
1383 /* Capture size limit reached, do we have another file? */
1384 if (capture_opts->multi_files_on) {
1385 if (cnd_autostop_files != NULL &&
1386 cnd_eval(cnd_autostop_files, ++autostop_files)) {
1387 /* no files left: stop here */
1392 /* Switch to the next ringbuffer file */
1393 if (ringbuf_switch_file(&ld.pdh, &capture_opts->save_file,
1394 &save_file_fd, &ld.bytes_written, &ld.err)) {
1395 /* File switch succeeded: reset the conditions */
1396 cnd_reset(cnd_autostop_size);
1397 if (cnd_file_duration) {
1398 cnd_reset(cnd_file_duration);
1400 libpcap_dump_flush(ld.pdh, NULL);
1401 report_packet_count(inpkts_to_sync_pipe);
1402 inpkts_to_sync_pipe = 0;
1403 report_new_capture_file(capture_opts->save_file);
1405 /* File switch failed: stop here */
1410 /* single file, stop now */
1414 } /* cnd_autostop_size */
1415 if (capture_opts->output_to_pipe) {
1416 libpcap_dump_flush(ld.pdh, NULL);
1420 /* Only update once a second (Win32: 500ms) so as not to overload slow
1421 * displays. This also prevents too much context-switching between the
1422 * dumpcap and wireshark processes */
1423 cur_time = TIME_GET();
1425 if ( (cur_time - upd_time) > 500) {
1427 if (cur_time - upd_time > 0) {
1429 upd_time = cur_time;
1431 /*if (pcap_stats(pch, stats) >= 0) {
1432 *stats_known = TRUE;
1435 /* Let the parent process know. */
1436 if (inpkts_to_sync_pipe) {
1438 libpcap_dump_flush(ld.pdh, NULL);
1440 /* Send our parent a message saying we've written out "inpkts_to_sync_pipe"
1441 packets to the capture file. */
1442 report_packet_count(inpkts_to_sync_pipe);
1444 inpkts_to_sync_pipe = 0;
1447 /* check capture duration condition */
1448 if (cnd_autostop_duration != NULL && cnd_eval(cnd_autostop_duration)) {
1449 /* The maximum capture time has elapsed; stop the capture. */
1454 /* check capture file duration condition */
1455 if (cnd_file_duration != NULL && cnd_eval(cnd_file_duration)) {
1456 /* duration limit reached, do we have another file? */
1457 if (capture_opts->multi_files_on) {
1458 if (cnd_autostop_files != NULL &&
1459 cnd_eval(cnd_autostop_files, ++autostop_files)) {
1460 /* no files left: stop here */
1465 /* Switch to the next ringbuffer file */
1466 if (ringbuf_switch_file(&ld.pdh, &capture_opts->save_file,
1467 &save_file_fd, &ld.bytes_written, &ld.err)) {
1468 /* file switch succeeded: reset the conditions */
1469 cnd_reset(cnd_file_duration);
1470 if(cnd_autostop_size)
1471 cnd_reset(cnd_autostop_size);
1472 libpcap_dump_flush(ld.pdh, NULL);
1473 report_packet_count(inpkts_to_sync_pipe);
1474 inpkts_to_sync_pipe = 0;
1475 report_new_capture_file(capture_opts->save_file);
1477 /* File switch failed: stop here */
1482 /* single file, stop now */
1486 } /* cnd_file_duration */
1489 } /* while (ld.go) */
1491 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_INFO, "Capture loop stopping ...");
1493 /* delete stop conditions */
1494 if (cnd_file_duration != NULL)
1495 cnd_delete(cnd_file_duration);
1496 if (cnd_autostop_files != NULL)
1497 cnd_delete(cnd_autostop_files);
1498 if (cnd_autostop_size != NULL)
1499 cnd_delete(cnd_autostop_size);
1500 if (cnd_autostop_duration != NULL)
1501 cnd_delete(cnd_autostop_duration);
1503 /* did we had a pcap (input) error? */
1505 g_snprintf(errmsg, sizeof(errmsg), "Error while capturing packets: %s",
1506 pcap_geterr(ld.pcap_h));
1507 report_capture_error(errmsg, please_report);
1509 else if (ld.from_cap_pipe && ld.cap_pipe_err == PIPERR)
1510 report_capture_error(errmsg, "");
1512 /* did we had an error while capturing? */
1516 capture_loop_get_errmsg(errmsg, sizeof(errmsg), capture_opts->save_file, ld.err,
1518 report_capture_error(errmsg, please_report);
1522 if (capture_opts->saving_to_file) {
1523 /* close the wiretap (output) file */
1524 close_ok = capture_loop_close_output(capture_opts, &ld, &err_close);
1528 /* there might be packets not yet notified to the parent */
1529 /* (do this after closing the file, so all packets are already flushed) */
1530 if(inpkts_to_sync_pipe) {
1531 report_packet_count(inpkts_to_sync_pipe);
1532 inpkts_to_sync_pipe = 0;
1535 /* If we've displayed a message about a write error, there's no point
1536 in displaying another message about an error on close. */
1537 if (!close_ok && write_ok) {
1538 capture_loop_get_errmsg(errmsg, sizeof(errmsg), capture_opts->save_file, err_close,
1540 report_capture_error(errmsg, "");
1544 * XXX We exhibit different behaviour between normal mode and sync mode
1545 * when the pipe is stdin and not already at EOF. If we're a child, the
1546 * parent's stdin isn't closed, so if the user starts another capture,
1547 * cap_pipe_open_live() will very likely not see the expected magic bytes and
1548 * will say "Unrecognized libpcap format". On the other hand, in normal
1549 * mode, cap_pipe_open_live() will say "End of file on pipe during open".
1552 /* get packet drop statistics from pcap */
1553 if(ld.pcap_h != NULL) {
1554 g_assert(!ld.from_cap_pipe);
1555 /* Get the capture statistics, so we know how many packets were
1557 if (pcap_stats(ld.pcap_h, stats) >= 0) {
1558 *stats_known = TRUE;
1559 /* Let the parent process know. */
1560 report_packet_drops(stats->ps_drop);
1562 g_snprintf(errmsg, sizeof(errmsg),
1563 "Can't get packet-drop statistics: %s",
1564 pcap_geterr(ld.pcap_h));
1565 report_capture_error(errmsg, please_report);
1569 /* close the input file (pcap or capture pipe) */
1570 capture_loop_close_input(&ld);
1572 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_INFO, "Capture loop stopped!");
1574 /* ok, if the write and the close were successful. */
1575 return write_ok && close_ok;
1578 if (capture_opts->multi_files_on) {
1579 /* cleanup ringbuffer */
1580 ringbuf_error_cleanup();
1582 /* We can't use the save file, and we have no FILE * for the stream
1583 to close in order to close it, so close the FD directly. */
1584 if(save_file_fd != -1) {
1585 eth_close(save_file_fd);
1588 /* We couldn't even start the capture, so get rid of the capture
1590 if(capture_opts->save_file != NULL) {
1591 eth_unlink(capture_opts->save_file);
1592 g_free(capture_opts->save_file);
1595 capture_opts->save_file = NULL;
1597 report_cfilter_error(capture_opts->cfilter, errmsg);
1599 report_capture_error(errmsg, secondary_errmsg);
1601 /* close the input file (pcap or cap_pipe) */
1602 capture_loop_close_input(&ld);
1604 g_log(LOG_DOMAIN_CAPTURE_CHILD, G_LOG_LEVEL_INFO, "Capture loop stopped with error");
1610 void capture_loop_stop(void)
1612 #ifdef HAVE_PCAP_BREAKLOOP
1613 if(ld.pcap_h != NULL)
1614 pcap_breakloop(ld.pcap_h);
1621 capture_loop_get_errmsg(char *errmsg, int errmsglen, const char *fname,
1622 int err, gboolean is_close)
1627 g_snprintf(errmsg, errmsglen,
1628 "Not all the packets could be written to the file"
1629 " to which the capture was being saved\n"
1630 "(\"%s\") because there is no space left on the file system\n"
1631 "on which that file resides.",
1637 g_snprintf(errmsg, errmsglen,
1638 "Not all the packets could be written to the file"
1639 " to which the capture was being saved\n"
1640 "(\"%s\") because you are too close to, or over,"
1641 " your disk quota\n"
1642 "on the file system on which that file resides.",
1647 case WTAP_ERR_CANT_CLOSE:
1648 g_snprintf(errmsg, errmsglen,
1649 "The file to which the capture was being saved"
1650 " couldn't be closed for some unknown reason.");
1653 case WTAP_ERR_SHORT_WRITE:
1654 g_snprintf(errmsg, errmsglen,
1655 "Not all the packets could be written to the file"
1656 " to which the capture was being saved\n"
1663 g_snprintf(errmsg, errmsglen,
1664 "The file to which the capture was being saved\n"
1665 "(\"%s\") could not be closed: %s.",
1666 fname, wtap_strerror(err));
1668 g_snprintf(errmsg, errmsglen,
1669 "An error occurred while writing to the file"
1670 " to which the capture was being saved\n"
1672 fname, wtap_strerror(err));
1679 /* one packet was captured, process it */
1681 capture_loop_packet_cb(u_char *user, const struct pcap_pkthdr *phdr,
1684 loop_data *ld = (void *) user;
1687 /* if the user told us to stop after x packets, do we have enough? */
1689 if ((ld->packet_max > 0) && (ld->packet_count >= ld->packet_max))
1695 /* We're supposed to write the packet to a file; do so.
1696 If this fails, set "ld->go" to FALSE, to stop the capture, and set
1697 "ld->err" to the error. */
1698 if (!libpcap_write_packet(ld->pdh, phdr, pd, &ld->bytes_written, &err)) {
1705 #endif /* HAVE_LIBPCAP */