/* -*- Mode: c; tab-width: 8; indent-tabs-mode: 1; c-basic-offset: 8; -*- */
/*
 * Copyright (c) 1994, 1995, 1996, 1997, 1998
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the Computer Systems
 *	Engineering Group at Lawrence Berkeley Laboratory.
 * 4. Neither the name of the University nor of the Laboratory may be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
static const char rcsid[] =
    "@(#) $Header: /tcpdump/master/libpcap/fad-getad.c,v 1.1 2002-07-27 18:46:21 guy Exp $ (LBL)";
#endif

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <sys/types.h>
#include <sys/socket.h>

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <ifaddrs.h>

#include "pcap-int.h"

#ifdef HAVE_OS_PROTO_H
#include "os-proto.h"
#endif

/*
 * Get a list of all interfaces that are up and that we can open.
 * Returns -1 on error, 0 otherwise.
 * The list, as returned through "alldevsp", may be null if no interfaces
 * were up and could be opened.
 *
 * This is the implementation used on platforms that have "getifaddrs()".
 */
int
pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf)
{
	pcap_if_t *devlist = NULL;
	struct ifaddrs *ifap, *ifa;
	struct sockaddr *broadaddr, *dstaddr;
	int ret = 0;

	/*
	 * Get the list of interface addresses.
	 *
	 * Note: this won't return information about interfaces
	 * with no addresses; are there any such interfaces
	 * that would be capable of receiving packets?
	 * (Interfaces incapable of receiving packets aren't
	 * very interesting from libpcap's point of view.)
	 *
	 * LAN interfaces will probably have link-layer
	 * addresses; I don't know whether all implementations
	 * of "getifaddrs()" now, or in the future, will return
	 * those.
	 */
	if (getifaddrs(&ifap) != 0) {
		(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
		    "getifaddrs: %s", pcap_strerror(errno));
		return (-1);
	}
	for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) {
		/*
		 * Is this interface up?
		 */
		if (!(ifa->ifa_flags & IFF_UP)) {
			/*
			 * No, so don't add it to the list.
			 */
			continue;
		}

		/*
		 * "ifa_broadaddr" may be non-null even on
		 * non-broadcast interfaces; "ifa_dstaddr"
		 * was, on at least one FreeBSD 4.1 system,
		 * non-null on a non-point-to-point
		 * interface.
		 */
		if (ifa->ifa_flags & IFF_BROADCAST)
			broadaddr = ifa->ifa_broadaddr;
		else
			broadaddr = NULL;
		if (ifa->ifa_flags & IFF_POINTOPOINT)
			dstaddr = ifa->ifa_dstaddr;
		else
			dstaddr = NULL;

		/*
		 * Add information for this address to the list.
		 */
		if (add_addr_to_iflist(&devlist, ifa->ifa_name,
		    ifa->ifa_flags, ifa->ifa_addr, ifa->ifa_netmask,
		    broadaddr, dstaddr, errbuf) < 0) {
			ret = -1;
			break;
		}
	}

	freeifaddrs(ifap);

	if (ret != -1) {
		/*
		 * We haven't had any errors yet; do any platform-specific
		 * operations to add devices.
		 */
		if (pcap_platform_finddevs(&devlist, errbuf) < 0)
			ret = -1;
	}

	if (ret == -1) {
		/*
		 * We had an error; free the list we've been constructing.
		 */
		if (devlist != NULL) {
			pcap_freealldevs(devlist);
			devlist = NULL;
		}
	}

	*alldevsp = devlist;
	return (ret);
}