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capture.c
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/* capture.c
* Routines for packet capture windows
*
* $Id: capture.c,v 1.153 2001/06/18 01:49:16 guy Exp $
*
* Ethereal - Network traffic analyzer
* By Gerald Combs <gerald@zing.org>
* Copyright 1998 Gerald Combs
*
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#ifdef HAVE_LIBPCAP
#ifdef HAVE_SYS_TYPES_H
# include <sys/types.h>
#endif
#ifdef HAVE_SYS_STAT_H
# include <sys/stat.h>
#endif
#ifdef HAVE_SYS_WAIT_H
# include <sys/wait.h>
#endif
#ifndef _WIN32
/*
* Define various POSIX macros (and, in the case of WCOREDUMP, non-POSIX
* macros) on UNIX systems that don't have them.
*/
#ifndef WIFEXITED
# define WIFEXITED(status) (((status) & 0177) == 0)
#endif
#ifndef WIFSTOPPED
# define WIFSTOPPED(status) (((status) & 0177) == 0177)
#endif
#ifndef WIFSIGNALED
# define WIFSIGNALED(status) (!WIFSTOPPED(status) && !WIFEXITED(status))
#endif
#ifndef WEXITSTATUS
# define WEXITSTATUS(status) ((status) >> 8)
#endif
#ifndef WTERMSIG
# define WTERMSIG(status) ((status) & 0177)
#endif
#ifndef WCOREDUMP
# define WCOREDUMP(status) ((status) & 0200)
#endif
#ifndef WSTOPSIG
# define WSTOPSIG(status) ((status) >> 8)
#endif
#endif /* _WIN32 */
#ifdef HAVE_IO_H
# include <io.h>
#endif
#include <gtk/gtk.h>
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <time.h>
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#include <signal.h>
#include <errno.h>
#include <pcap.h>
#ifdef NEED_SNPRINTF_H
# include "snprintf.h"
#endif
#ifdef _WIN32
#include <process.h> /* For spawning child process */
#endif
/*
* XXX - the various BSDs appear to define BSD in <sys/param.h>; we don't
* want to include it if it's not present on this platform, however.
*/
#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__bsdi__)
#ifndef BSD
#define BSD
#endif /* BSD */
#endif /* defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__bsdi__) */
/*
* We don't want to do a "select()" on the pcap_t's file descriptor on
* BSD (because "select()" doesn't work correctly on BPF devices on at
* least some releases of some flavors of BSD), and we don't want to do
* it on Windows (because "select()" is something for sockets, not for
* arbitrary handles).
*
* We *do* want to do it on other platforms, as, on other platforms (with
* the possible exception of Ultrix and Digital UNIX), the read timeout
* doesn't expire if no packets have arrived, so a "pcap_dispatch()" call
* will block until packets arrive, causing the UI to hang.
*/
#if !defined(BSD) && !defined(_WIN32)
# define MUST_DO_SELECT
#endif
#include "gtk/main.h"
#include "gtk/gtkglobals.h"
#include "packet.h"
#include "file.h"
#include "capture.h"
#include "util.h"
#include "simple_dialog.h"
#include "prefs.h"
#include "globals.h"
#include "wiretap/libpcap.h"
#include "wiretap/wtap.h"
#include "packet-clip.h"
#include "packet-eth.h"
#include "packet-fddi.h"
#include "packet-null.h"
#include "packet-ppp.h"
#include "packet-raw.h"
#include "packet-sll.h"
#include "packet-tr.h"
#include "packet-ieee80211.h"
#include "packet-chdlc.h"
static int sync_pipe[2]; /* used to sync father */
enum PIPES { READ, WRITE }; /* Constants 0 and 1 for READ and WRITE */
int quit_after_cap; /* Makes a "capture only mode". Implies -k */
gboolean capture_child; /* if this is the child for "-S" */
static int fork_child; /* In parent, process ID of child */
static guint cap_input_id;
/*
* Indications sent out on the sync pipe.
*/
#define SP_CAPSTART ';' /* capture start message */
#define SP_PACKET_COUNT '*' /* count of packets captured since last message */
#define SP_ERROR_MSG '!' /* length of error message that follows */
#define SP_DROPS '#' /* count of packets dropped in capture */
#ifdef _WIN32
static guint cap_timer_id;
static int cap_timer_cb(gpointer); /* Win32 kludge to check for pipe input */
#endif
static void cap_file_input_cb(gpointer, gint, GdkInputCondition);
static void wait_for_child(gboolean);
#ifndef _WIN32
static char *signame(int);
#endif
static void capture_delete_cb(GtkWidget *, GdkEvent *, gpointer);
static void capture_stop_cb(GtkWidget *, gpointer);
static void capture_pcap_cb(u_char *, const struct pcap_pkthdr *,
const u_char *);
static void get_capture_file_io_error(char *, int, const char *, int, gboolean);
static void send_errmsg_to_parent(const char *);
static float pct(gint, gint);
static void stop_capture(int signo);
typedef struct _loop_data {
gint go; /* TRUE as long as we're supposed to keep capturing */
gint max; /* Number of packets we're supposed to capture - 0 means infinite */
int err; /* if non-zero, error seen while capturing */
gint linktype;
gint sync_packets;
gboolean from_pipe; /* TRUE if we are capturing data from a pipe */
gboolean modified; /* TRUE if data in the pipe uses modified pcap headers */
gboolean byte_swapped; /* TRUE if data in the pipe is byte swapped */
packet_counts counts;
wtap_dumper *pdh;
} loop_data;
#ifndef _WIN32
static void adjust_header(loop_data *, struct pcap_hdr *, struct pcaprec_hdr *);
static int pipe_open_live(char *, struct pcap_hdr *, loop_data *, char *);
static int pipe_dispatch(int, loop_data *, struct pcap_hdr *);
#endif
/* Win32 needs the O_BINARY flag for open() */
#ifndef O_BINARY
#define O_BINARY 0
#endif
#ifdef _WIN32
/* Win32 needs a handle to the child capture process */
int child_process;
#endif
/* Add a string pointer to a NULL-terminated array of string pointers. */
static char **
add_arg(char **args, int *argc, char *arg)
{
/* Grow the array; "*argc" currently contains the number of string
pointers, *not* counting the NULL pointer at the end, so we have
to add 2 in order to get the new size of the array, including the
new pointer and the terminating NULL pointer. */
args = g_realloc(args, (*argc + 2) * sizeof (char *));
/* Stuff the pointer into the penultimate element of the array, which
is the one at the index specified by "*argc". */
args[*argc] = arg;
/* Now bump the count. */
(*argc)++;
/* We overwrite the NULL pointer; put it back right after the
element we added. */
args[*argc] = NULL;
return args;
}
#ifdef _WIN32
/* Given a string, return a pointer to a quote-encapsulated version of
the string, so we can pass it as an argument with "spawnvp" even
if it contains blanks. */
char *
quote_encapsulate(const char *string)
{
char *encapsulated_string;
encapsulated_string = g_new(char, strlen(string) + 3);
sprintf(encapsulated_string, "\"%s\"", string);
return encapsulated_string;
}
#endif
/* Open a specified file, or create a temporary file, and start a capture
to the file in question. */
void
do_capture(char *capfile_name)
{
char tmpname[128+1];
gboolean is_tempfile;
u_char c;
int i;
guint byte_count;
char *msg;
int err;
int capture_succeeded;
gboolean stats_known;
struct pcap_stat stats;
if (capfile_name != NULL) {
/* Try to open/create the specified file for use as a capture buffer. */
cfile.save_file_fd = open(capfile_name, O_RDWR|O_BINARY|O_TRUNC|O_CREAT, 0600);
is_tempfile = FALSE;
} else {
/* Choose a random name for the capture buffer */
cfile.save_file_fd = create_tempfile(tmpname, sizeof tmpname, "ether");
capfile_name = g_strdup(tmpname);
is_tempfile = TRUE;
}
if (cfile.save_file_fd == -1) {
if (is_tempfile) {
simple_dialog(ESD_TYPE_CRIT, NULL,
"The temporary file to which the capture would be saved (\"%s\")"
"could not be opened: %s.", capfile_name, strerror(errno));
} else {
simple_dialog(ESD_TYPE_CRIT, NULL,
file_open_error_message(errno, TRUE), capfile_name);
}
return;
}
close_cap_file(&cfile);
g_assert(cfile.save_file == NULL);
cfile.save_file = capfile_name;
if (prefs.capture_real_time) { /* do the capture in a child process */
char ssnap[24];
char scount[24]; /* need a constant for len of numbers */
char save_file_fd[24];
char errmsg[1024+1];
int error;
int argc;
char **argv;
#ifdef _WIN32
char sync_pipe_fd[24];
char *fontstring;
char *filterstring;
#endif
/* Allocate the string pointer array with enough space for the
terminating NULL pointer. */
argc = 0;
argv = g_malloc(sizeof (char *));
*argv = NULL;
/* Now add those arguments used on all platforms. */
argv = add_arg(argv, &argc, CHILD_NAME);
argv = add_arg(argv, &argc, "-i");
argv = add_arg(argv, &argc, cfile.iface);
argv = add_arg(argv, &argc, "-w");
argv = add_arg(argv, &argc, cfile.save_file);
argv = add_arg(argv, &argc, "-W");
sprintf(save_file_fd,"%d",cfile.save_file_fd); /* in lieu of itoa */
argv = add_arg(argv, &argc, save_file_fd);
argv = add_arg(argv, &argc, "-c");
sprintf(scount,"%d",cfile.count);
argv = add_arg(argv, &argc, scount);
argv = add_arg(argv, &argc, "-s");
sprintf(ssnap,"%d",cfile.snap);
argv = add_arg(argv, &argc, ssnap);
if (!prefs.capture_prom_mode)
argv = add_arg(argv, &argc, "-p");
#ifdef _WIN32
/* Create a pipe for the child process */
if(_pipe(sync_pipe, 512, O_BINARY) < 0) {
/* Couldn't create the pipe between parent and child. */
error = errno;
unlink(cfile.save_file);
g_free(cfile.save_file);
cfile.save_file = NULL;
simple_dialog(ESD_TYPE_CRIT, NULL, "Couldn't create sync pipe: %s",
strerror(error));
return;
}
/* Convert font name to a quote-encapsulated string and pass to child */
argv = add_arg(argv, &argc, "-m");
fontstring = quote_encapsulate(prefs.gui_font_name);
argv = add_arg(argv, &argc, fontstring);
/* Convert pipe write handle to a string and pass to child */
argv = add_arg(argv, &argc, "-Z");
itoa(sync_pipe[WRITE], sync_pipe_fd, 10);
argv = add_arg(argv, &argc, sync_pipe_fd);
/* Convert filter string to a quote delimited string and pass to child */
if (cfile.cfilter != NULL && strlen(cfile.cfilter) != 0) {
argv = add_arg(argv, &argc, "-f");
filterstring = quote_encapsulate(cfile.cfilter);
argv = add_arg(argv, &argc, filterstring);
}
/* Spawn process */
fork_child = spawnvp(_P_NOWAIT, ethereal_path, argv);
g_free(fontstring);
g_free(filterstring);
/* Keep a copy for later evaluation by _cwait() */
child_process = fork_child;
#else
signal(SIGCHLD, SIG_IGN);
if (pipe(sync_pipe) < 0) {
/* Couldn't create the pipe between parent and child. */
error = errno;
unlink(cfile.save_file);
g_free(cfile.save_file);
cfile.save_file = NULL;
simple_dialog(ESD_TYPE_CRIT, NULL, "Couldn't create sync pipe: %s",
strerror(error));
return;
}
argv = add_arg(argv, &argc, "-m");
argv = add_arg(argv, &argc, prefs.gui_font_name);
if (cfile.cfilter != NULL && strlen(cfile.cfilter) != 0) {
argv = add_arg(argv, &argc, "-f");
argv = add_arg(argv, &argc, cfile.cfilter);
}
if ((fork_child = fork()) == 0) {
/*
* Child process - run Ethereal with the right arguments to make
* it just pop up the live capture dialog box and capture with
* the specified capture parameters, writing to the specified file.
*
* args: -i interface specification
* -w file to write
* -W file descriptor to write
* -c count to capture
* -s snaplen
* -m / -b fonts
* -f "filter expression"
*/
close(1);
dup(sync_pipe[WRITE]);
close(sync_pipe[READ]);
execvp(ethereal_path, argv);
snprintf(errmsg, sizeof errmsg, "Couldn't run %s in child process: %s",
ethereal_path, strerror(errno));
send_errmsg_to_parent(errmsg);
/* Exit with "_exit()", so that we don't close the connection
to the X server (and cause stuff buffered up by our parent but
not yet sent to be sent, as that stuff should only be sent by
our parent). */
_exit(2);
}
#endif
/* Parent process - read messages from the child process over the
sync pipe. */
g_free(argv); /* free up arg array */
/* Close the write side of the pipe, so that only the child has it
open, and thus it completely closes, and thus returns to us
an EOF indication, if the child closes it (either deliberately
or by exiting abnormally). */
close(sync_pipe[WRITE]);
/* Close the save file FD, as we won't be using it - we'll be opening
it and reading the save file through Wiretap. */
close(cfile.save_file_fd);
if (fork_child == -1) {
/* We couldn't even create the child process. */
error = errno;
close(sync_pipe[READ]);
unlink(cfile.save_file);
g_free(cfile.save_file);
cfile.save_file = NULL;
simple_dialog(ESD_TYPE_CRIT, NULL, "Couldn't create child process: %s",
strerror(error));
return;
}
/* Read a byte count from "sync_pipe[READ]", terminated with a
colon; if the count is 0, the child process created the
capture file and we should start reading from it, otherwise
the capture couldn't start and the count is a count of bytes
of error message, and we should display the message. */
byte_count = 0;
for (;;) {
i = read(sync_pipe[READ], &c, 1);
if (i == 0) {
/* EOF - the child process died.
Close the read side of the sync pipe, remove the capture file,
and report the failure. */
close(sync_pipe[READ]);
unlink(cfile.save_file);
g_free(cfile.save_file);
cfile.save_file = NULL;
wait_for_child(TRUE);
return;
}
if (c == SP_CAPSTART || c == SP_ERROR_MSG)
break;
if (!isdigit(c)) {
/* Child process handed us crap.
Close the read side of the sync pipe, remove the capture file,
and report the failure. */
close(sync_pipe[READ]);
unlink(cfile.save_file);
g_free(cfile.save_file);
cfile.save_file = NULL;
simple_dialog(ESD_TYPE_WARN, NULL,
"Capture child process sent us a bad message");
return;
}
byte_count = byte_count*10 + c - '0';
}
if (c == SP_CAPSTART) {
/* Success. Open the capture file, and set up to read it. */
err = start_tail_cap_file(cfile.save_file, is_tempfile, &cfile);
if (err == 0) {
/* We were able to open and set up to read the capture file;
arrange that our callback be called whenever it's possible
to read from the sync pipe, so that it's called when
the child process wants to tell us something. */
#ifdef _WIN32
/* Tricky to use pipes in win9x, as no concept of wait. NT can
do this but that doesn't cover all win32 platforms. GTK can do
this but doesn't seem to work over processes. Attempt to do
something similar here, start a timer and check for data on every
timeout. */
cap_timer_id = gtk_timeout_add(1000, cap_timer_cb, NULL);
#else
cap_input_id = gtk_input_add_full(sync_pipe[READ],
GDK_INPUT_READ|GDK_INPUT_EXCEPTION,
cap_file_input_cb,
NULL,
(gpointer) &cfile,
NULL);
#endif
} else {
/* We weren't able to open the capture file; complain, and
close the sync pipe. */
simple_dialog(ESD_TYPE_CRIT, NULL,
file_open_error_message(err, FALSE), cfile.save_file);
/* Close the sync pipe. */
close(sync_pipe[READ]);
/* Don't unlink the save file - leave it around, for debugging
purposes. */
g_free(cfile.save_file);
cfile.save_file = NULL;
}
} else {
/* Failure - the child process sent us a message indicating
what the problem was. */
if (byte_count == 0) {
/* Zero-length message? */
simple_dialog(ESD_TYPE_WARN, NULL,
"Capture child process failed, but its error message was empty.");
} else {
msg = g_malloc(byte_count + 1);
if (msg == NULL) {
simple_dialog(ESD_TYPE_WARN, NULL,
"Capture child process failed, but its error message was too big.");
} else {
i = read(sync_pipe[READ], msg, byte_count);
msg[byte_count] = '\0';
if (i < 0) {
simple_dialog(ESD_TYPE_WARN, NULL,
"Capture child process failed: Error %s reading its error message.",
strerror(errno));
} else if (i == 0) {
simple_dialog(ESD_TYPE_WARN, NULL,
"Capture child process failed: EOF reading its error message.");
wait_for_child(FALSE);
} else
simple_dialog(ESD_TYPE_WARN, NULL, msg);
g_free(msg);
}
/* Close the sync pipe. */
close(sync_pipe[READ]);
/* Get rid of the save file - the capture never started. */
unlink(cfile.save_file);
g_free(cfile.save_file);
cfile.save_file = NULL;
}
}
} else {
/* Not sync mode. */
capture_succeeded = capture(&stats_known, &stats);
if (quit_after_cap) {
/* DON'T unlink the save file. Presumably someone wants it. */
gtk_exit(0);
}
if (capture_succeeded) {
/* Capture succeeded; read in the capture file. */
if ((err = open_cap_file(cfile.save_file, is_tempfile, &cfile)) == 0) {
/* Set the read filter to NULL. */
cfile.rfcode = NULL;
/* Get the packet-drop statistics.
XXX - there are currently no packet-drop statistics stored
in libpcap captures, and that's what we're reading.
At some point, we will add support in Wiretap to return
packet-drop statistics for capture file formats that store it,
and will make "read_cap_file()" get those statistics from
Wiretap. We clear the statistics (marking them as "not known")
in "open_cap_file()", and "read_cap_file()" will only fetch
them and mark them as known if Wiretap supplies them, so if
we get the statistics now, after calling "open_cap_file()" but
before calling "read_cap_file()", the values we store will
be used by "read_cap_file()".
If a future libpcap capture file format stores the statistics,
we'll put them into the capture file that we write, and will
thus not have to set them here - "read_cap_file()" will get
them from the file and use them. */
if (stats_known) {
cfile.drops_known = TRUE;
/* XXX - on some systems, libpcap doesn't bother filling in
"ps_ifdrop" - it doesn't even set it to zero - so we don't
bother looking at it.
Ideally, libpcap would have an interface that gave us
several statistics - perhaps including various interface
error statistics - and would tell us which of them it
supplies, allowing us to display only the ones it does. */
cfile.drops = stats.ps_drop;
}
switch (read_cap_file(&cfile, &err)) {
case READ_SUCCESS:
case READ_ERROR:
/* Just because we got an error, that doesn't mean we were unable
to read any of the file; we handle what we could get from the
file. */
break;
case READ_ABORTED:
/* Exit by leaving the main loop, so that any quit functions
we registered get called. */
gtk_main_quit();
return;
}
}
}
/* We're not doing a capture any more, so we don't have a save
file. */
g_free(cfile.save_file);
cfile.save_file = NULL;
}
}
#ifdef _WIN32
/* The timer has expired, see if there's stuff to read from the pipe,
if so call the cap_file_input_cb */
static gint
cap_timer_cb(gpointer data)
{
HANDLE handle;
DWORD avail = 0;
gboolean result, result1;
DWORD childstatus;
/* Oddly enough although Named pipes don't work on win9x,
PeekNamedPipe does !!! */
handle = (HANDLE) _get_osfhandle (sync_pipe[READ]);
result = PeekNamedPipe(handle, NULL, 0, NULL, &avail, NULL);
/* Get the child process exit status */
result1 = GetExitCodeProcess((HANDLE)child_process, &childstatus);
/* If the Peek returned an error, or there are bytes to be read
or the childwatcher thread has terminated then call the normal
callback */
if (!result || avail > 0 || childstatus != STILL_ACTIVE) {
/* avoid reentrancy problems and stack overflow */
gtk_timeout_remove(cap_timer_id);
/* And call the real handler */
cap_file_input_cb((gpointer) &cfile, 0, 0);
/* Return false so that the timer is not run again */
return FALSE;
}
else {
/* No data so let timer run again */
return TRUE;
}
}
#endif
/* There's stuff to read from the sync pipe, meaning the child has sent
us a message, or the sync pipe has closed, meaning the child has
closed it (perhaps because it exited). */
static void
cap_file_input_cb(gpointer data, gint source, GdkInputCondition condition)
{
capture_file *cf = (capture_file *)data;
#define BUFSIZE 4096
char buffer[BUFSIZE+1], *p = buffer, *q = buffer, *msg, *r;
int nread, msglen, chars_to_copy;
int to_read = 0;
int err;
#ifndef _WIN32
/* avoid reentrancy problems and stack overflow */
gtk_input_remove(cap_input_id);
#endif
if ((nread = read(sync_pipe[READ], buffer, BUFSIZE)) <= 0) {
/* The child has closed the sync pipe, meaning it's not going to be
capturing any more packets. Pick up its exit status, and
complain if it did anything other than exit with status 0. */
wait_for_child(FALSE);
/* Read what remains of the capture file, and finish the capture.
XXX - do something if this fails? */
switch (finish_tail_cap_file(cf, &err)) {
case READ_SUCCESS:
case READ_ERROR:
/* Just because we got an error, that doesn't mean we were unable
to read any of the file; we handle what we could get from the
file. */
break;
case READ_ABORTED:
/* Exit by leaving the main loop, so that any quit functions
we registered get called. */
gtk_main_quit();
return;
}
/* We're not doing a capture any more, so we don't have a save
file. */
g_free(cf->save_file);
cf->save_file = NULL;
return;
}
buffer[nread] = '\0';
while (nread != 0) {
/* look for (possibly multiple) indications */
switch (*q) {
case SP_PACKET_COUNT :
to_read += atoi(p);
p = q + 1;
q++;
nread--;
break;
case SP_DROPS :
cf->drops_known = TRUE;
cf->drops = atoi(p);
p = q + 1;
q++;
nread--;
break;
case SP_ERROR_MSG :
msglen = atoi(p);
p = q + 1;
q++;
nread--;
/* Read the entire message.
XXX - if the child hasn't sent it all yet, this could cause us
to hang until they do. */
msg = g_malloc(msglen + 1);
r = msg;
while (msglen != 0) {
if (nread == 0) {
/* Read more. */
if ((nread = read(sync_pipe[READ], buffer, BUFSIZE)) <= 0)
break;
p = buffer;
q = buffer;
}
chars_to_copy = MIN(msglen, nread);
memcpy(r, q, chars_to_copy);
r += chars_to_copy;
q += chars_to_copy;
nread -= chars_to_copy;
msglen -= chars_to_copy;
}
*r = '\0';
simple_dialog(ESD_TYPE_WARN, NULL, msg);
g_free(msg);
break;
default :
q++;
nread--;
break;
}
}
/* Read from the capture file the number of records the child told us
it added.
XXX - do something if this fails? */
switch (continue_tail_cap_file(cf, to_read, &err)) {
case READ_SUCCESS:
case READ_ERROR:
/* Just because we got an error, that doesn't mean we were unable
to read any of the file; we handle what we could get from the
file.
XXX - abort on a read error? */
break;
case READ_ABORTED:
/* Kill the child capture process; the user wants to exit, and we
shouldn't just leave it running. */
#ifdef _WIN32
/* XXX - kill it. */
#else
kill(fork_child, SIGTERM); /* SIGTERM so it can clean up if necessary */
#endif
break;
}
/* restore pipe handler */
#ifdef _WIN32
cap_timer_id = gtk_timeout_add(1000, cap_timer_cb, NULL);
#else
cap_input_id = gtk_input_add_full (sync_pipe[READ],
GDK_INPUT_READ|GDK_INPUT_EXCEPTION,
cap_file_input_cb,
NULL,
(gpointer) cf,
NULL);
#endif
}
static void
wait_for_child(gboolean always_report)
{
int wstatus;
#ifdef _WIN32
/* XXX - analyze the wait stuatus and display more information
in the dialog box? */
if (_cwait(&wstatus, child_process, _WAIT_CHILD) == -1) {
simple_dialog(ESD_TYPE_WARN, NULL, "Child capture process stopped unexpectedly");
}
#else
if (wait(&wstatus) != -1) {
if (WIFEXITED(wstatus)) {
/* The child exited; display its exit status, if it's not zero,
and even if it's zero if "always_report" is true. */
if (always_report || WEXITSTATUS(wstatus) != 0) {
simple_dialog(ESD_TYPE_WARN, NULL,
"Child capture process exited: exit status %d",
WEXITSTATUS(wstatus));
}
} else if (WIFSTOPPED(wstatus)) {
/* It stopped, rather than exiting. "Should not happen." */
simple_dialog(ESD_TYPE_WARN, NULL,
"Child capture process stopped: %s",
signame(WSTOPSIG(wstatus)));
} else if (WIFSIGNALED(wstatus)) {
/* It died with a signal. */
simple_dialog(ESD_TYPE_WARN, NULL,
"Child capture process died: %s%s",
signame(WTERMSIG(wstatus)),
WCOREDUMP(wstatus) ? " - core dumped" : "");
} else {
/* What? It had to either have exited, or stopped, or died with
a signal; what happened here? */
simple_dialog(ESD_TYPE_WARN, NULL,
"Child capture process died: wait status %#o", wstatus);
}
}
#endif
}
#ifndef _WIN32
static char *
signame(int sig)
{
char *sigmsg;
static char sigmsg_buf[6+1+3+1];
switch (sig) {
case SIGHUP:
sigmsg = "Hangup";
break;
case SIGINT:
sigmsg = "Interrupted";
break;
case SIGQUIT:
sigmsg = "Quit";
break;
case SIGILL:
sigmsg = "Illegal instruction";
break;
case SIGTRAP:
sigmsg = "Trace trap";
break;
case SIGABRT:
sigmsg = "Abort";
break;
case SIGFPE:
sigmsg = "Arithmetic exception";
break;
case SIGKILL:
sigmsg = "Killed";
break;
case SIGBUS:
sigmsg = "Bus error";
break;
case SIGSEGV:
sigmsg = "Segmentation violation";
break;
/* http://metalab.unc.edu/pub/Linux/docs/HOWTO/GCC-HOWTO
Linux is POSIX compliant. These are not POSIX-defined signals ---
ISO/IEC 9945-1:1990 (IEEE Std 1003.1-1990), paragraph B.3.3.1.1 sez:
``The signals SIGBUS, SIGEMT, SIGIOT, SIGTRAP, and SIGSYS
were omitted from POSIX.1 because their behavior is
implementation dependent and could not be adequately catego-
rized. Conforming implementations may deliver these sig-
nals, but must document the circumstances under which they
are delivered and note any restrictions concerning their
delivery.''
So we only check for SIGSYS on those systems that happen to
implement them (a system can be POSIX-compliant and implement
them, it's just that POSIX doesn't *require* a POSIX-compliant
system to implement them).
*/
#ifdef SIGSYS
case SIGSYS:
sigmsg = "Bad system call";
break;
#endif
case SIGPIPE:
sigmsg = "Broken pipe";
break;
case SIGALRM:
sigmsg = "Alarm clock";
break;
case SIGTERM:
sigmsg = "Terminated";
break;
default:
sprintf(sigmsg_buf, "Signal %d", sig);
sigmsg = sigmsg_buf;
break;
}
return sigmsg;
}
#endif
/*
* Timeout, in milliseconds, for reads from the stream of captured packets.
*/
#define CAP_READ_TIMEOUT 250
#ifndef _WIN32
/* Take carre of byte order in the libpcap headers read from pipes.
* (function taken from wiretap/libpcap.c) */
static void
adjust_header(loop_data *ld, struct pcap_hdr *hdr, struct pcaprec_hdr *rechdr)
{
if (ld->byte_swapped) {
/* Byte-swap the record header fields. */
rechdr->ts_sec = BSWAP32(rechdr->ts_sec);
rechdr->ts_usec = BSWAP32(rechdr->ts_usec);
rechdr->incl_len = BSWAP32(rechdr->incl_len);
rechdr->orig_len = BSWAP32(rechdr->orig_len);
}
/* In file format version 2.3, the "incl_len" and "orig_len" fields were
swapped, in order to match the BPF header layout.
Unfortunately, some files were, according to a comment in the "libpcap"
source, written with version 2.3 in their headers but without the
interchanged fields, so if "incl_len" is greater than "orig_len" - which
would make no sense - we assume that we need to swap them. */
if (hdr->version_major == 2 &&
(hdr->version_minor < 3 ||
(hdr->version_minor == 3 && rechdr->incl_len > rechdr->orig_len))) {
guint32 temp;
temp = rechdr->orig_len;
rechdr->orig_len = rechdr->incl_len;
rechdr->incl_len = temp;
}
}
/* Mimic pcap_open_live() for pipe captures
* We check if "pipename" is "-" (stdin) or a FIFO, open it, and read the
* header.