/* capture-pcap-util-unix.c
* UN*X-specific utility routines for packet capture
*
* $Id: capture-pcap-util-unix.c 20521 2007-01-21 23:45:36Z guy $
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.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
#include <glib.h>
#ifdef HAVE_LIBPCAP
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#include <pcap.h>
/*
* Keep Digital UNIX happy when including <net/if.h>.
*/
struct mbuf;
struct rtentry;
#include <net/if.h>
#ifdef HAVE_SYS_SOCKIO_H
# include <sys/sockio.h>
#endif
#include "capture-pcap-util.h"
#include "capture-pcap-util-int.h"
#ifndef HAVE_PCAP_FINDALLDEVS
struct search_user_data {
char *name;
if_info_t *if_info;
};
static void
search_for_if_cb(gpointer data, gpointer user_data);
#endif
GList *
get_interface_list(int *err, char **err_str)
{
#ifdef HAVE_PCAP_FINDALLDEVS
return get_interface_list_findalldevs(err, err_str);
#else
GList *il = NULL;
gint nonloopback_pos = 0;
struct ifreq *ifr, *last;
struct ifconf ifc;
struct ifreq ifrflags;
int sock = socket(AF_INET, SOCK_DGRAM, 0);
struct search_user_data user_data;
pcap_t *pch;
int len, lastlen;
char *buf;
if_info_t *if_info;
char errbuf[PCAP_ERRBUF_SIZE];
if (sock < 0) {
*err = CANT_GET_INTERFACE_LIST;
if (err_str != NULL) {
*err_str = g_strdup_printf(
"Can't get list of interfaces: error opening socket: %s",
strerror(errno));
}
return NULL;
}
/*
* This code came from: W. Richard Stevens: "UNIX Network Programming",
* Networking APIs: Sockets and XTI, Vol 1, page 434.
*/
lastlen = 0;
len = 100 * sizeof(struct ifreq);
for ( ; ; ) {
buf = g_malloc(len);
ifc.ifc_len = len;
ifc.ifc_buf = buf;
memset (buf, 0, len);
if (ioctl(sock, SIOCGIFCONF, &ifc) < 0) {
if (errno != EINVAL || lastlen != 0) {
if (err_str != NULL) {
*err_str = g_strdup_printf(
"Can't get list of interfaces: SIOCGIFCONF ioctl error: %s",
strerror(errno));
}
goto fail;
}
} else {
if ((unsigned) ifc.ifc_len < sizeof(struct ifreq)) {
if (err_str != NULL) {
*err_str = g_strdup(
"Can't get list of interfaces: SIOCGIFCONF ioctl gave too small return buffer");
}
goto fail;
}
if (ifc.ifc_len == lastlen)
break; /* success, len has not changed */
lastlen = ifc.ifc_len;
}
len += 10 * sizeof(struct ifreq); /* increment */
g_free(buf);
}
ifr = (struct ifreq *) ifc.ifc_req;
last = (struct ifreq *) ((char *) ifr + ifc.ifc_len);
while (ifr < last) {
/*
* Skip entries that begin with "dummy", or that include
* a ":" (the latter are Solaris virtuals).
*/
if (strncmp(ifr->ifr_name, "dummy", 5) == 0 ||
strchr(ifr->ifr_name, ':') != NULL)
goto next;
/*
* If we already have this interface name on the list,
* don't add it, but, if we don't already have an IP
* address for it, add that address (SIOCGIFCONF returns,
* at least on BSD-flavored systems, one entry per
* interface *address*; if an interface has multiple
* addresses, we get multiple entries for it).
*/
user_data.name = ifr->ifr_name;
user_data.if_info = NULL;
g_list_foreach(il, search_for_if_cb, &user_data);
if (user_data.if_info != NULL) {
if_info_add_address(user_data.if_info, &ifr->ifr_addr);
goto next;
}
/*
* Get the interface flags.
*/
memset(&ifrflags, 0, sizeof ifrflags);
strncpy(ifrflags.ifr_name, ifr->ifr_name,
sizeof ifrflags.ifr_name);
if (ioctl(sock, SIOCGIFFLAGS, (char *)&ifrflags) < 0) {
if (errno == ENXIO)
goto next;
if (err_str != NULL) {
*err_str = g_strdup_printf(
"Can't get list of interfaces: SIOCGIFFLAGS error getting flags for interface %s: %s",
ifr->ifr_name, strerror(errno));
}
goto fail;
}
/*
* Skip interfaces that aren't up.
*/
if (!(ifrflags.ifr_flags & IFF_UP))
goto next;
/*
* Skip interfaces that we can't open with "libpcap".
* Open with the minimum packet size - it appears that the
* IRIX SIOCSNOOPLEN "ioctl" may fail if the capture length
* supplied is too large, rather than just truncating it.
*/
pch = pcap_open_live(ifr->ifr_name, MIN_PACKET_SIZE, 0, 0,
errbuf);
if (pch == NULL)
goto next;
pcap_close(pch);
/*
* If it's a loopback interface, add it at the end of the
* list, otherwise add it after the last non-loopback
* interface, so all loopback interfaces go at the end - we
* don't want a loopback interface to be the default capture
* device unless there are no non-loopback devices.
*/
if_info = if_info_new(ifr->ifr_name, NULL);
if_info_add_address(if_info, &ifr->ifr_addr);
if ((ifrflags.ifr_flags & IFF_LOOPBACK) ||
strncmp(ifr->ifr_name, "lo", 2) == 0) {
if_info->loopback = TRUE;
il = g_list_append(il, if_info);
} else {
if_info->loopback = FALSE;
il = g_list_insert(il, if_info, nonloopback_pos);
/*
* Insert the next non-loopback interface after this
* one.
*/
nonloopback_pos++;
}
next:
#ifdef HAVE_SA_LEN
ifr = (struct ifreq *) ((char *) ifr +
(ifr->ifr_addr.sa_len > sizeof(ifr->ifr_addr) ?
ifr->ifr_addr.sa_len : sizeof(ifr->ifr_addr)) +
IFNAMSIZ);
#else
ifr = (struct ifreq *) ((char *) ifr + sizeof(struct ifreq));
#endif
}
#ifdef linux
/*
* OK, maybe we have support for the "any" device, to do a cooked
* capture on all interfaces at once.
* Try opening it and, if that succeeds, add it to the end of
* the list of interfaces.
*/
pch = pcap_open_live("any", MIN_PACKET_SIZE, 0, 0, errbuf);
if (pch != NULL) {
/*
* It worked; we can use the "any" device.
*/
if_info = if_info_new("any",
"Pseudo-device that captures on all interfaces");
il = g_list_insert(il, if_info, -1);
pcap_close(pch);
}
#endif
g_free(ifc.ifc_buf);
close(sock);
if (il == NULL) {
/*
* No interfaces found.
*/
*err = NO_INTERFACES_FOUND;
if (err_str != NULL)
*err_str = NULL;
}
return il;
fail:
if (il != NULL)
free_interface_list(il);
g_free(ifc.ifc_buf);
close(sock);
*err = CANT_GET_INTERFACE_LIST;
return NULL;
#endif /* HAVE_PCAP_FINDALLDEVS */
}
#ifndef HAVE_PCAP_FINDALLDEVS
static void
search_for_if_cb(gpointer data, gpointer user_data)
{
struct search_user_data *search_user_data = user_data;
if_info_t *if_info = data;
if (strcmp(if_info->name, search_user_data->name) == 0)
search_user_data->if_info = if_info;
}
#endif /* HAVE_PCAP_FINDALLDEVS */
/*
* Get an error message string for a CANT_GET_INTERFACE_LIST error from
* "get_interface_list()".
*/
gchar *
cant_get_if_list_error_message(const char *err_str)
{
return g_strdup_printf("Can't get list of interfaces: %s", err_str);
}
/*
* Append the version of libpcap with which we were compiled to a GString.
*/
void
get_compiled_pcap_version(GString *str)
{
#ifdef HAVE_PCAP_VERSION
extern char pcap_version[];
g_string_sprintfa(str, "with libpcap %s", pcap_version);
#else
g_string_append(str, "with libpcap (version unknown)");
#endif
}
/*
* Append the version of libpcap with which we we're running to a GString.
*/
void
get_runtime_pcap_version(GString *str)
{
g_string_sprintfa(str, "with ");
#ifdef HAVE_PCAP_LIB_VERSION
g_string_sprintfa(str, pcap_lib_version());
#else
g_string_append(str, "libpcap (version unknown)");
#endif
}
#else /* HAVE_LIBPCAP */
/*
* Append an indication that we were not compiled with libpcap
* to a GString.
*/
void
get_compiled_pcap_version(GString *str)
{
g_string_append(str, "without libpcap");
}
/*
* Don't append anything, as we weren't even compiled to use WinPcap.
*/
void
get_runtime_pcap_version(GString *str _U_)
{
}
#endif /* HAVE_LIBPCAP */
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