/* capture-pcap-util.c
 * Utility routines for packet capture
 *
 * $Id: capture-pcap-util.c 46172 2012-11-24 19:08:28Z 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., 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"

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

#ifdef _WIN32
#include "capture_win_ifnames.h" /* windows friendly interface names */
#else
#include "capture_unix_ifnames.h"
#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);
#ifdef _WIN32
	/*
	 * 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.
	 * If there's no description, fetch a friendly name
	 * if we can; if that fails, then, for a loopback
	 * interface, give it the friendly name "Loopback".
	 */
	if_info->friendly_name = g_strdup(description);
	if (if_info->friendly_name == NULL) {
		if_info->friendly_name = get_unix_interface_friendly_name(name);
		if (if_info->friendly_name == NULL) {
			/*
			 * 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 */