/* capture-pcap-util-unix.c

* UN*X-specific utility routines for packet capture

*

* $Id$

*

* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

*/

#include "config.h"

#include <glib.h>

#ifdef HAVE_LIBPCAP

#ifndef HAVE_PCAP_FINDALLDEVS

#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

/*

* 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"

#else

#include <pcap.h>

#endif /* HAVE_PCAP_FINDALLDEVS */

#include "capture_ifinfo.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

#ifdef HAVE_PCAP_REMOTE

GList *

get_remote_interface_list(const char *hostname, const char *port,

int auth_type, const char *username,

const char *passwd, int *err, char **err_str)

{

struct pcap_rmtauth auth;

char source[PCAP_BUF_SIZE];

char errbuf[PCAP_ERRBUF_SIZE];

GList *result;

if (pcap_createsrcstr(source, PCAP_SRC_IFREMOTE, hostname, port,

NULL, errbuf) == -1) {

*err = CANT_GET_INTERFACE_LIST;

if (err_str != NULL)

*err_str = cant_get_if_list_error_message(errbuf);

return NULL;

}

auth.type = auth_type;

auth.username = g_strdup(username);

auth.password = g_strdup(passwd);

result = get_interface_list_findalldevs_ex(source, &auth, err, err_str);

g_free(auth.username);

g_free(auth.password);

return result;

}

#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];

gboolean loopback;

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",

g_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",

g_strerror(errno));

}

goto fail;

}

} else {

if ((unsigned int) 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);

g_strlcpy(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, g_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.

*/

loopback = ((ifrflags.ifr_flags & IFF_LOOPBACK) ||

strncmp(ifr->ifr_name, "lo", 2) == 0);

if_info = if_info_new(ifr->ifr_name, NULL, loopback);

if_info_add_address(if_info, &ifr->ifr_addr);

if (loopback)

il = g_list_append(il, if_info);

else {

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", FALSE);

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)

{

/*

* NOTE: in *some* flavors of UN*X, the data from a shared

* library might be linked into executable images that are

* linked with that shared library, in which case you could

* look at pcap_version[] to get the version with which

* the program was compiled.

*

* In other flavors of UN*X, that doesn't happen, so

* pcap_version[] gives you the version the program is

* running with, not the version it was built with, and,

* in at least some of them, if the length of a data item

* referred to by the executable - such as the pcap_version[]

* string - isn't the same in the version of the library

* with which the program was built and the version with

* which it was run, the run-time linker will complain,

* which is Not Good.

*

* So, for now, we just give up on reporting the version

* of libpcap with which we were compiled.

*/

g_string_append(str, "with libpcap");

}

/*

* Append the version of libpcap with which we we're running to a GString.

*/

void

get_runtime_pcap_version(GString *str)

{

g_string_append_printf(str, "with ");

#ifdef HAVE_PCAP_LIB_VERSION

g_string_append(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 */