path: root/capture-pcap-util.c

/* capture-pcap-util.c
 * 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"

#ifdef HAVE_LIBPCAP

#include <glib.h>

#include <stdlib.h>
#include <stdio.h>
#include <limits.h>
#include <string.h>

#ifdef HAVE_SYS_TYPES_H
# include <sys/types.h>
#endif

#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif

#include <wtap.h>
#include <libpcap.h>

#include "capture_ifinfo.h"
#include "capture-pcap-util.h"
#include "capture-pcap-util-int.h"

#include "wsutil/file_util.h"

#ifndef _WIN32
#include <netinet/in.h>
#endif

#ifdef _WIN32
#include "capture_win_ifnames.h" /* windows friendly interface names */
#endif

/*
 * Given an interface name, find the "friendly name" and interface
 * type for the interface.
 */

#if defined(__APPLE__)

#include <CoreFoundation/CoreFoundation.h>
#include <SystemConfiguration/SystemConfiguration.h>

#include "cfutils.h"

/*
 * On OS X, we get the "friendly name" and interface type for the interface
 * from the System Configuration framework.
 *
 * To find the System Configuration framework information for the
 * interface, we get all the interfaces that the System Configuration
 * framework knows about and look for the one with a "BSD name" matching
 * the interface name.
 *
 * If we find it, we use its "localized display name", if it has one, as
 * the "friendly name".
 *
 * As for the interface type:
 *
 * Yes, fetching all the network addresses for an interface gets you an
 * AF_LINK address, of type "struct sockaddr_dl", and, yes, that includes
 * an SNMP MIB-II ifType value.
 *
 * However, it's IFT_ETHER, i.e. Ethernet, for AirPort interfaces,
 * not IFT_IEEE80211 (which isn't defined in OS X in any case).
 *
 * Perhaps some other BSD-flavored OSes won't make this mistake;
 * however, FreeBSD 7.0 and OpenBSD 4.2, at least, appear to have
 * made the same mistake, at least for my Belkin ZyDAS stick.
 *
 * SCNetworkInterfaceGetInterfaceType() will get the interface
 * type.  The interface type is a CFString, and:
 *
 *    kSCNetworkInterfaceTypeIEEE80211 means IF_WIRELESS;
 *    kSCNetworkInterfaceTypeBluetooth means IF_BLUETOOTH;
 *    kSCNetworkInterfaceTypeModem or
 *    kSCNetworkInterfaceTypePPP or
 *    maybe kSCNetworkInterfaceTypeWWAN means IF_DIALUP
 */
static void
add_unix_interface_ifinfo(if_info_t *if_info, const char *name,
    const char *description _U_)
{
	CFStringRef name_CFString;
	CFArrayRef interfaces;
	CFIndex num_interfaces;
	CFIndex i;
	SCNetworkInterfaceRef interface;
	CFStringRef bsdname_CFString;
	CFStringRef friendly_name_CFString;
	CFStringRef interface_type_CFString;

	interfaces = SCNetworkInterfaceCopyAll();
	if (interfaces == NULL) {
		/*
		 * Couldn't get a list of interfaces.
		 */
		return;
	}

	name_CFString = CFStringCreateWithCString(kCFAllocatorDefault,
	    name, kCFStringEncodingUTF8);
	if (name_CFString == NULL) {
		/*
		 * Couldn't convert the interface name to a CFString.
		 */
		CFRelease(interfaces);
		return;
	}

	num_interfaces = CFArrayGetCount(interfaces);
	for (i = 0; i < num_interfaces; i++) {
		interface = (SCNetworkInterfaceRef)CFArrayGetValueAtIndex(interfaces, i);
		bsdname_CFString = SCNetworkInterfaceGetBSDName(interface);
		if (bsdname_CFString == NULL) {
			/*
			 * This interface has no BSD name, so it's not
			 * a regular network interface.
			 */
			continue;
		}
		if (CFStringCompare(name_CFString, bsdname_CFString, 0) == 0) {
			/*
			 * This is the interface.
			 * First, get the friendly name.
			 */
			friendly_name_CFString = SCNetworkInterfaceGetLocalizedDisplayName(interface);
			if (friendly_name_CFString != NULL)
				if_info->friendly_name = CFString_to_C_string(friendly_name_CFString);

			/*
			 * Now get the interface type.
			 */
			interface_type_CFString = SCNetworkInterfaceGetInterfaceType(interface);
			if (CFStringCompare(interface_type_CFString,
			    kSCNetworkInterfaceTypeIEEE80211, 0) == kCFCompareEqualTo)
				if_info->type = IF_WIRELESS;
			else if (CFStringCompare(interface_type_CFString,
			    kSCNetworkInterfaceTypeBluetooth, 0) == kCFCompareEqualTo)
				if_info->type = IF_BLUETOOTH;
			else if (CFStringCompare(interface_type_CFString,
			    kSCNetworkInterfaceTypeModem, 0) == kCFCompareEqualTo)
				if_info->type = IF_DIALUP;
			else if (CFStringCompare(interface_type_CFString,
			    kSCNetworkInterfaceTypePPP, 0) == kCFCompareEqualTo)
				if_info->type = IF_DIALUP;
			else if (CFStringCompare(interface_type_CFString,
			    kSCNetworkInterfaceTypeWWAN, 0) == kCFCompareEqualTo)
				if_info->type = IF_DIALUP;
			else
				if_info->type = IF_WIRED;
			break;
		}
	}

	CFRelease(interfaces);
	CFRelease(name_CFString);
}
#elif defined(__linux__)
/*
 * Linux doesn't offer any form of "friendly name", but you can
 * determine an interface type to some degree.
 */
static void
add_unix_interface_ifinfo(if_info_t *if_info, const char *name,
    const char *description _U_)
{
	char *wireless_path;
	ws_statb64 statb;

	/*
	 * Look for /sys/class/net/{device}/wireless.  If it exists,
	 * it's a wireless interface.
	 */
	wireless_path = g_strdup_printf("/sys/class/net/%s/wireless", name);
	if (wireless_path != NULL) {
		if (ws_stat64(wireless_path, &statb) == 0)
			if_info->type = IF_WIRELESS;
		g_free(wireless_path);
	}
	if (if_info->type == IF_WIRED) {
		/*
		 * We still don't know what it is.  Check for
		 * Bluetooth and USB devices.
		 */
		if (strstr(name, "bluetooth") != NULL) {
			/*
			 * XXX - this is for raw Bluetooth capture; what
			 * about IP-over-Bluetooth devices?
			 */
			if_info->type = IF_BLUETOOTH;
		} else if (strstr(name, "usbmon") != NULL)
			if_info->type = IF_USB;
	}
}
#else
/*
 * On other UN*Xes, if there is a description, it's a friendly
 * name, and there is no vendor description.  ("Other UN*Xes"
 * currently means "FreeBSD and OpenBSD".)
 */
void
add_unix_interface_ifinfo(if_info_t *if_info, const char *name _U_,
    const char *description)
{
	if_info->friendly_name = g_strdup(description);
}
#endif

if_info_t *
if_info_new(const char *name, const char *description, gboolean loopback)
{
	if_info_t *if_info;
#ifdef _WIN32
	const char *guid_text;
	GUID guid;
#endif

	if_info = (if_info_t *)g_malloc(sizeof (if_info_t));
	if_info->name = g_strdup(name);
	if_info->friendly_name = NULL;	/* default - unknown */
	if_info->vendor_description = NULL;
	if_info->type = IF_WIRED;	/* default */
#ifdef _WIN32
	/*
	 * Get the interface type.
	 *
	 * Much digging failed to reveal any obvious way to get something
	 * such as the SNMP MIB-II ifType value for an interface:
	 *
	 *    http://www.iana.org/assignments/ianaiftype-mib
	 *
	 * by making some NDIS request.  And even if there were such
	 * a way, there's no guarantee that the ifType reflects an
	 * interface type that a user would view as correct (for
	 * example, some systems report Wi-Fi interfaces as
	 * Ethernet interfaces).
	 *
	 * So we look for keywords in the vendor's interface
	 * description.
	 */
	if (description && (strstr(description, "generic dialup") != NULL ||
	    strstr(description, "PPP/SLIP") != NULL)) {
		if_info->type = IF_DIALUP;
	} else if (description && (strstr(description, "Wireless") != NULL ||
	    strstr(description,"802.11") != NULL)) {
		if_info->type = IF_WIRELESS;
	} else if (description && strstr(description, "AirPcap") != NULL ||
	    strstr(name, "airpcap") != NULL) {
		if_info->type = IF_AIRPCAP;
	} else if (description && strstr(description, "Bluetooth") != NULL ) {
		if_info->type = IF_BLUETOOTH;
	} else if (description && strstr(description, "VMware") != NULL) {
		/*
		 * Bridge, NAT, or host-only interface on a VMware host.
		 *
		 * XXX - what about guest interfaces?
		 */
		if_info->type = IF_VIRTUAL;
	}

	/*
	 * On Windows, the "description" is a vendor description,
	 * and the friendly name isn't returned by WinPcap.
	 * Fetch it ourselves.
	 */

	/*
	 * Skip over the "\Device\NPF_" prefix in the device name,
	 * if present.
	 */
	if (strncmp("\\Device\\NPF_", name, 12) == 0)
		guid_text = name + 12;
	else
		guid_text = name;

	/* Now try to parse what remains as a GUID. */
	if (parse_as_guid(guid_text, &guid)) {
		/*
		 * Success. Try to get a friendly name using the GUID.
		 * As this is a regular interface, the description is a
		 * vendor description.
		 */
		if_info->friendly_name = get_interface_friendly_name_from_device_guid(&guid);
		if_info->vendor_description = g_strdup(description);
	} else {
		/*
		 * This is probably not a regular interface; we only
		 * support NT 5 (W2K) and later, so all regular interfaces
		 * should have GUIDs at the end of the name.  Therefore,
		 * the description, if supplied, is a friendly name
		 * provided by WinPcap, and there is no vendor
		 * description.
		 */
		if_info->friendly_name = g_strdup(description);
		if_info->vendor_description = NULL;
	}
#else
	/*
	 * On UN*X, if there is a description, it's a friendly
	 * name, and there is no vendor description.
	 *
	 * Try the platform's way of getting a friendly name and
	 * interface type first.
	 *
	 * If that fails, then, for a loopback interface, give it the
	 * friendly name "Loopback" and, for VMware interfaces,
	 * give them the type IF_VIRTUAL.
	 */
	add_unix_interface_ifinfo(if_info, name, description);
	if (if_info->type == IF_WIRED) {
		/*
		 * This is the default interface type.
		 *
		 * Bridge, NAT, or host-only interfaces on VMWare hosts
		 * have the name vmnet[0-9]+. Guests might use a native
		 * (LANCE or E1000) driver or the vmxnet driver.  Check
		 * the name.
		 */
		if (g_ascii_strncasecmp(name, "vmnet", 5) == 0)
			if_info->type = IF_VIRTUAL;
		else if (g_ascii_strncasecmp(name, "vmxnet", 6) == 0)
			if_info->type = IF_VIRTUAL;
	}
	if (if_info->friendly_name == NULL) {
		/*
		 * We couldn't get interface information using platform-
		 * dependent calls.
		 *
		 * If this is a loopback interface, give it a
		 * "friendly name" of "Loopback".
		 */
		if (loopback)
			if_info->friendly_name = g_strdup("Loopback");
	}
	if_info->vendor_description = NULL;
#endif
	if_info->loopback = loopback;
	if_info->addrs = NULL;
	return if_info;
}

void
if_info_add_address(if_info_t *if_info, struct sockaddr *addr)
{
	if_addr_t *if_addr;
	struct sockaddr_in *ai;
#ifdef INET6
	struct sockaddr_in6 *ai6;
#endif

	switch (addr->sa_family) {

	case AF_INET:
		ai = (struct sockaddr_in *)(void *)addr;
		if_addr = (if_addr_t *)g_malloc(sizeof(*if_addr));
		if_addr->ifat_type = IF_AT_IPv4;
		if_addr->addr.ip4_addr =
		    *((guint32 *)&(ai->sin_addr.s_addr));
		if_info->addrs = g_slist_append(if_info->addrs, if_addr);
		break;

#ifdef INET6
	case AF_INET6:
		ai6 = (struct sockaddr_in6 *)(void *)addr;
		if_addr = (if_addr_t *)g_malloc(sizeof(*if_addr));
		if_addr->ifat_type = IF_AT_IPv6;
		memcpy((void *)&if_addr->addr.ip6_addr,
		    (void *)&ai6->sin6_addr.s6_addr,
		    sizeof if_addr->addr.ip6_addr);
		if_info->addrs = g_slist_append(if_info->addrs, if_addr);
		break;
#endif
	}
}

#ifdef HAVE_PCAP_FINDALLDEVS
/*
 * Get all IP address information for the given interface.
 */
static void
if_info_ip(if_info_t *if_info, pcap_if_t *d)
{
	pcap_addr_t *a;

	/* All addresses */
	for (a = d->addresses; a != NULL; a = a->next) {
		if (a->addr != NULL)
			if_info_add_address(if_info, a->addr);
	}
}

#ifdef HAVE_PCAP_REMOTE
GList *
get_interface_list_findalldevs_ex(const char *source,
                                  struct pcap_rmtauth *auth,
                                  int *err, char **err_str)
{
	GList  *il = NULL;
	pcap_if_t *alldevs, *dev;
	if_info_t *if_info;
	char errbuf[PCAP_ERRBUF_SIZE];

        if (pcap_findalldevs_ex((char *)source, auth, &alldevs, errbuf) == -1) {
		*err = CANT_GET_INTERFACE_LIST;
		if (err_str != NULL)
			*err_str = cant_get_if_list_error_message(errbuf);
		return NULL;
	}

	if (alldevs == NULL) {
		/*
		 * No interfaces found.
		 */
		*err = NO_INTERFACES_FOUND;
		if (err_str != NULL)
			*err_str = NULL;
		return NULL;
	}

	for (dev = alldevs; dev != NULL; dev = dev->next) {
		if_info = if_info_new(dev->name, dev->description,
		    (dev->flags & PCAP_IF_LOOPBACK) ? TRUE : FALSE);
		il = g_list_append(il, if_info);
		if_info_ip(if_info, dev);
	}
	pcap_freealldevs(alldevs);

	return il;
}
#endif

GList *
get_interface_list_findalldevs(int *err, char **err_str)
{
	GList  *il = NULL;
	pcap_if_t *alldevs, *dev;
	if_info_t *if_info;
	char errbuf[PCAP_ERRBUF_SIZE];

	if (pcap_findalldevs(&alldevs, errbuf) == -1) {
		*err = CANT_GET_INTERFACE_LIST;
		if (err_str != NULL)
			*err_str = cant_get_if_list_error_message(errbuf);
		return NULL;
	}

	if (alldevs == NULL) {
		/*
		 * No interfaces found.
		 */
		*err = NO_INTERFACES_FOUND;
		if (err_str != NULL)
			*err_str = NULL;
		return NULL;
	}

	for (dev = alldevs; dev != NULL; dev = dev->next) {
		if_info = if_info_new(dev->name, dev->description,
		    (dev->flags & PCAP_IF_LOOPBACK) ? TRUE : FALSE);
		il = g_list_append(il, if_info);
		if_info_ip(if_info, dev);
	}
	pcap_freealldevs(alldevs);

	return il;
}
#endif /* HAVE_PCAP_FINDALLDEVS */

static void
free_if_info_addr_cb(gpointer addr, gpointer user_data _U_)
{
	g_free(addr);
}

static void
free_if_cb(gpointer data, gpointer user_data _U_)
{
	if_info_t *if_info = (if_info_t *)data;

	g_free(if_info->name);
	g_free(if_info->friendly_name);
	g_free(if_info->vendor_description);

	g_slist_foreach(if_info->addrs, free_if_info_addr_cb, NULL);
	g_slist_free(if_info->addrs);
	g_free(if_info);
}

void
free_interface_list(GList *if_list)
{
	g_list_foreach(if_list, free_if_cb, NULL);
	g_list_free(if_list);
}

#if !defined(HAVE_PCAP_DATALINK_NAME_TO_VAL) || !defined(HAVE_PCAP_DATALINK_VAL_TO_NAME) || !defined(HAVE_PCAP_DATALINK_VAL_TO_DESCRIPTION)
struct dlt_choice {
	const char *name;
	const char *description;
	int	dlt;
};

#define DLT_CHOICE(code, description) { #code, description, code }
#define DLT_CHOICE_SENTINEL { NULL, NULL, 0 }

static struct dlt_choice dlt_choices[] = {
	DLT_CHOICE(DLT_NULL, "BSD loopback"),
	DLT_CHOICE(DLT_EN10MB, "Ethernet"),
	DLT_CHOICE(DLT_IEEE802, "Token ring"),
	DLT_CHOICE(DLT_ARCNET, "ARCNET"),
	DLT_CHOICE(DLT_SLIP, "SLIP"),
	DLT_CHOICE(DLT_PPP, "PPP"),
	DLT_CHOICE(DLT_FDDI, "FDDI"),
	DLT_CHOICE(DLT_ATM_RFC1483, "RFC 1483 IP-over-ATM"),
	DLT_CHOICE(DLT_RAW, "Raw IP"),
	DLT_CHOICE(DLT_SLIP_BSDOS, "BSD/OS SLIP"),
	DLT_CHOICE(DLT_PPP_BSDOS, "BSD/OS PPP"),
	DLT_CHOICE(DLT_ATM_CLIP, "Linux Classical IP-over-ATM"),
	DLT_CHOICE(DLT_PPP_SERIAL, "PPP over serial"),
	DLT_CHOICE(DLT_PPP_ETHER, "PPPoE"),
	DLT_CHOICE(DLT_C_HDLC, "Cisco HDLC"),
	DLT_CHOICE(DLT_IEEE802_11, "802.11"),
	DLT_CHOICE(DLT_FRELAY, "Frame Relay"),
	DLT_CHOICE(DLT_LOOP, "OpenBSD loopback"),
	DLT_CHOICE(DLT_ENC, "OpenBSD encapsulated IP"),
	DLT_CHOICE(DLT_LINUX_SLL, "Linux cooked"),
	DLT_CHOICE(DLT_LTALK, "Localtalk"),
	DLT_CHOICE(DLT_PFLOG, "OpenBSD pflog file"),
	DLT_CHOICE(DLT_PRISM_HEADER, "802.11 plus Prism header"),
	DLT_CHOICE(DLT_IP_OVER_FC, "RFC 2625 IP-over-Fibre Channel"),
	DLT_CHOICE(DLT_SUNATM, "Sun raw ATM"),
	DLT_CHOICE(DLT_IEEE802_11_RADIO, "802.11 plus BSD radio information header"),
	DLT_CHOICE(DLT_APPLE_IP_OVER_IEEE1394, "Apple IP-over-IEEE 1394"),
	DLT_CHOICE(DLT_ARCNET_LINUX, "Linux ARCNET"),
	DLT_CHOICE(DLT_LINUX_IRDA, "Linux IrDA"),
	DLT_CHOICE(DLT_IEEE802_11_RADIO_AVS, "802.11 plus AVS radio information header"),
	DLT_CHOICE_SENTINEL
};

#if !defined(HAVE_PCAP_DATALINK_NAME_TO_VAL)
static int
pcap_datalink_name_to_val(const char *name)
{
	int i;

	for (i = 0; dlt_choices[i].name != NULL; i++) {
		if (g_ascii_strcasecmp(dlt_choices[i].name + sizeof("DLT_") - 1,
		    name) == 0)
			return (dlt_choices[i].dlt);
	}
	return (-1);
}
#endif /* defined(HAVE_PCAP_DATALINK_NAME_TO_VAL) */

#if !defined(HAVE_PCAP_DATALINK_VAL_TO_NAME)
static const char *
pcap_datalink_val_to_name(int dlt)
{
	int i;

	for (i = 0; dlt_choices[i].name != NULL; i++) {
		if (dlt_choices[i].dlt == dlt)
			return (dlt_choices[i].name + sizeof("DLT_") - 1);
	}
	return (NULL);
}
#endif /* defined(HAVE_PCAP_DATALINK_VAL_TO_NAME) */

#if !defined(HAVE_PCAP_DATALINK_VAL_TO_DESCRIPTION)
const char *
pcap_datalink_val_to_description(int dlt)
{
	int i;

	for (i = 0; dlt_choices[i].name != NULL; i++) {
		if (dlt_choices[i].dlt == dlt)
			return (dlt_choices[i].description);
	}
	return (NULL);
}
#endif /* defined(HAVE_PCAP_DATALINK_VAL_TO_DESCRIPTION) */

#endif /* !defined(HAVE_PCAP_DATALINK_VAL_TO_NAME) || !defined(HAVE_PCAP_DATALINK_VAL_TO_DESCRIPTION) */

static void
free_linktype_cb(gpointer data, gpointer user_data _U_)
{
	data_link_info_t *linktype_info = (data_link_info_t *)data;

	g_free(linktype_info->name);
	g_free(linktype_info->description);
}

void
free_if_capabilities(if_capabilities_t *caps)
{
	g_list_foreach(caps->data_link_types, free_linktype_cb, NULL);
	g_list_free(caps->data_link_types);
	g_free(caps);
}

const char *
linktype_val_to_name(int dlt)
{
    return pcap_datalink_val_to_name(dlt);
}

int linktype_name_to_val(const char *linktype)
{
    return pcap_datalink_name_to_val(linktype);
}

#endif /* HAVE_LIBPCAP */