/* $Id: mcast.c,v 1.15.2.4 2005/01/12 02:25:47 horms Exp $ */
/*
 * mcast.c: implements hearbeat API for UDP multicast communication
 *
 * Copyright (C) 2000 Alan Robertson <alanr@unix.sh>
 * Copyright (C) 2000 Chris Wright <chris@wirex.com>
 *
 * Thanks to WireX for providing hardware to test on.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <portability.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <ctype.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <sys/ioctl.h>

#ifdef HAVE_SYS_SOCKIO_H
#	include <sys/sockio.h>
#endif

#include <HBcomm.h>
 
#define PIL_PLUGINTYPE          HB_COMM_TYPE
#define PIL_PLUGINTYPE_S        HB_COMM_TYPE_S
#define PIL_PLUGIN              mcast
#define PIL_PLUGIN_S            "mcast"
#define PIL_PLUGINLICENSE	LICENSE_LGPL
#define PIL_PLUGINLICENSEURL	URL_LGPL
#include <pils/plugin.h>
#include <heartbeat.h>

struct mcast_private {
	char *  interface;      /* Interface name */
	struct  in_addr mcast;  /* multicast address */
	struct  sockaddr_in   addr;   /* multicast addr */
	u_short port;
	int     rsocket;        /* Read-socket */
	int     wsocket;        /* Write-socket */
	u_char	ttl;		/* TTL value for outbound packets */
	u_char	loop;		/* boolean, loop back outbound packets */
};


static int		mcast_parse(const char* configline);
static struct hb_media * mcast_new(const char * intf, const char *mcast
			,	u_short port, u_char ttl, u_char loop);
static int		mcast_open(struct hb_media* mp);
static int		mcast_close(struct hb_media* mp);
static void*		mcast_read(struct hb_media* mp, int* lenp);
static int		mcast_write(struct hb_media* mp, void* p, int len);
static int		mcast_descr(char** buffer);
static int		mcast_mtype(char** buffer);
static int		mcast_isping(void);


/*
 * mcastclose is called as part of unloading the mcast HBcomm plugin.
 * If there was any global data allocated, or file descriptors opened, etc.
 * which is associated with the plugin, and not a single interface
 * in particular, here's our chance to clean it up.
 */

static void
mcastclosepi(PILPlugin*pi)
{
}


/*
 * mcastcloseintf called as part of shutting down the mcast HBcomm interface.
 * If there was any global data allocated, or file descriptors opened, etc.
 * which is associated with the mcast implementation, here's our chance
 * to clean it up.
 */
static PIL_rc
mcastcloseintf(PILInterface* pi, void* pd)
{
	return PIL_OK;
}

static struct hb_media_fns mcastOps ={
	NULL,		/* Create single object function */
	mcast_parse,	/* whole-line parse function */
	mcast_open,
	mcast_close,
	mcast_read,
	mcast_write,
	mcast_mtype,
	mcast_descr,
	mcast_isping,
};

PIL_PLUGIN_BOILERPLATE("1.0", Debug, mcastclosepi);
static const PILPluginImports*  PluginImports;
static PILPlugin*               OurPlugin;
static PILInterface*		OurInterface;
static struct hb_media_imports*	OurImports;
static void*			interfprivate;

#define LOG	PluginImports->log
#define MALLOC	PluginImports->alloc
#define STRDUP  PluginImports->mstrdup
#define FREE	PluginImports->mfree

PIL_rc
PIL_PLUGIN_INIT(PILPlugin*us, const PILPluginImports* imports);

PIL_rc
PIL_PLUGIN_INIT(PILPlugin*us, const PILPluginImports* imports)
{
	/* Force the compiler to do a little type checking */
	(void)(PILPluginInitFun)PIL_PLUGIN_INIT;

	PluginImports = imports;
	OurPlugin = us;

	/* Register ourself as a plugin */
	imports->register_plugin(us, &OurPIExports);  

	/*  Register our interface implementation */
 	return imports->register_interface(us, PIL_PLUGINTYPE_S
	,	PIL_PLUGIN_S
	,	&mcastOps
	,	mcastcloseintf		/*close */
	,	&OurInterface
	,	(void*)&OurImports
	,	interfprivate); 
}


/* helper functions */
static int mcast_make_receive_sock(struct hb_media* hbm);
static int mcast_make_send_sock(struct hb_media * hbm);
static struct mcast_private *
new_mcast_private(const char *ifn, const char *mcast, u_short port,
		u_char ttl, u_char loop);
static int set_mcast_if(int sockfd, char *ifname);
static int set_mcast_loop(int sockfd, u_char loop);
static int set_mcast_ttl(int sockfd, u_char ttl);
static int join_mcast_group(int sockfd, struct in_addr *addr, char *ifname);
static int if_getaddr(const char *ifname, struct in_addr *addr);
static int is_valid_dev(const char *dev);
static int is_valid_mcast_addr(const char *addr);
static int get_port(const char *port, u_short *p);
static int get_ttl(const char *ttl, u_char *t);
static int get_loop(const char *loop, u_char *l);


#define		ISMCASTOBJECT(mp) ((mp) && ((mp)->vf == (void*)&mcastOps))
#define		MCASTASSERT(mp)	g_assert(ISMCASTOBJECT(mp))

static int
mcast_mtype(char** buffer)
{ 
	*buffer = STRDUP(PIL_PLUGIN_S);
	if (!*buffer) {
		return 0;
	}

	return STRLEN(*buffer);
}

static int
mcast_descr(char **buffer)
{ 
	*buffer = STRDUP("UDP/IP multicast");
	if (!*buffer) {
		return 0;
	}

	return STRLEN(*buffer);
}

static int
mcast_isping(void)
{
	/* nope, this is not a ping device */
	return 0;
}

/* mcast_parse will parse the line in the config file that is 
 * associated with the media's type (hb_dev_mtype).  It should 
 * receive the rest of the line after the mtype.  And it needs
 * to call hb_dev_new, add the media to the list of available media.
 *
 * So in this case, the config file line should look like
 * mcast [device] [mcast group] [port] [mcast ttl] [mcast loop]
 * for example:
 * mcast eth0 225.0.0.1 694 1 0
 */

static int
mcast_parse(const char *line)
{
	const char *	bp = line;
	char		dev[MAXLINE];
	char		mcast[MAXLINE];
	char		token[MAXLINE];
	u_short		port;
	u_char		ttl;
	u_char		loop;
	int		toklen;
	struct hb_media *	mp;

	/* Skip over white space, then grab the device */
	bp += strspn(bp, WHITESPACE);
	toklen = strcspn(bp, WHITESPACE);
	strncpy(dev, bp, toklen);
	bp += toklen;
	dev[toklen] = EOS;

	if (*dev != EOS)  {
		if (!is_valid_dev(dev)) {
			PILCallLog(LOG, PIL_CRIT, "mcast bad device [%s]", dev);
			return HA_FAIL;
		}
		/* Skip over white space, then grab the multicast group */
		bp += strspn(bp, WHITESPACE);
		toklen = strcspn(bp, WHITESPACE);
		strncpy(mcast, bp, toklen);
		bp += toklen;
		mcast[toklen] = EOS;
	
		if (*mcast == EOS)  {
			PILCallLog(LOG, PIL_CRIT, "mcast [%s] missing mcast address",
				dev);
			return(HA_FAIL);
		}
		if (!is_valid_mcast_addr(mcast)) {
			PILCallLog(LOG, PIL_CRIT, "mcast [%s] bad addr [%s]", dev, mcast);
			return(HA_FAIL);
		}

		/* Skip over white space, then grab the port */
		bp += strspn(bp, WHITESPACE);
		toklen = strcspn(bp, WHITESPACE);
		strncpy(token, bp, toklen);
		bp += toklen;
		token[toklen] = EOS;

		if (*token == EOS)  {
			PILCallLog(LOG, PIL_CRIT, "mcast [%s] missing port", dev);
			return(HA_FAIL);
		}
		if (get_port(token, &port) == -1) {
			PILCallLog(LOG, PIL_CRIT, " mcast [%s] bad port [%d]", dev, port);
			return HA_FAIL;
		}

		/* Skip over white space, then grab the ttl */
		bp += strspn(bp, WHITESPACE);
		toklen = strcspn(bp, WHITESPACE);
		strncpy(token, bp, toklen);
		bp += toklen;
		token[toklen] = EOS;

		if (*token == EOS)  {
			PILCallLog(LOG, PIL_CRIT, "mcast [%s] missing ttl", dev);
			return(HA_FAIL);
		}
		if (get_ttl(token, &ttl) == -1) {
			PILCallLog(LOG, PIL_CRIT, " mcast [%s] bad ttl [%d]", dev, ttl);
			return HA_FAIL;
		}

		/* Skip over white space, then grab the loop */
		bp += strspn(bp, WHITESPACE);
		toklen = strcspn(bp, WHITESPACE);
		strncpy(token, bp, toklen);
		bp += toklen;
		token[toklen] = EOS;

		if (*token == EOS)  {
			PILCallLog(LOG, PIL_CRIT, "mcast [%s] missing loop", dev);
			return(HA_FAIL);
		}
		if (get_loop(token, &loop) == -1) {
			PILCallLog(LOG, PIL_CRIT, " mcast [%s] bad loop [%d]", dev, loop);
			return HA_FAIL;
		}

		if ((mp = mcast_new(dev, mcast, port, ttl, loop)) == NULL) {
			return(HA_FAIL);
		}
		OurImports->RegisterNewMedium(mp);
	}

	return(HA_OK);
}

/*
 * Create new UDP/IP multicast heartbeat object 
 * pass in name of interface, multicast address, port, multicast
 * ttl, and multicast loopback value as parameters.
 * This should get called from hb_dev_parse().
 */
static struct hb_media *
mcast_new(const char * intf, const char *mcast, u_short port,
		    u_char ttl, u_char loop)
{
	struct mcast_private*	mcp;
	struct hb_media *	ret;

	/* create new mcast_private struct...hmmm...who frees it? */
	mcp = new_mcast_private(intf, mcast, port, ttl, loop);
	if (mcp == NULL) {
		PILCallLog(LOG, PIL_WARN, "Error creating mcast_private(%s, %s, %d, %d, %d)",
			 intf, mcast, port, ttl, loop);
		return(NULL);
	}
	ret = (struct hb_media*) MALLOC(sizeof(struct hb_media));
	if (ret != NULL) {
		char * name;
		ret->pd = (void*)mcp;
		name = STRDUP(intf);
		if (name != NULL) {
			ret->name = name;
		}
		else {
			FREE(ret);
			ret = NULL;
		}

	}
	if(ret == NULL) {
		FREE(mcp->interface);
		FREE(mcp);
	}
	return(ret);
}

/*
 *	Open UDP/IP multicast heartbeat interface
 */
static int
mcast_open(struct hb_media* hbm)
{
	struct mcast_private * mcp;

	MCASTASSERT(hbm);
	mcp = (struct mcast_private *) hbm->pd;

	if ((mcp->wsocket = mcast_make_send_sock(hbm)) < 0) {
		return(HA_FAIL);
	}
	if ((mcp->rsocket = mcast_make_receive_sock(hbm)) < 0) {
		mcast_close(hbm);
		return(HA_FAIL);
	}

	PILCallLog(LOG, PIL_INFO, "UDP multicast heartbeat started for group %s "
		"port %d interface %s (ttl=%d loop=%d)" , inet_ntoa(mcp->mcast),
		mcp->port, mcp->interface, mcp->ttl, mcp->loop);

	return(HA_OK);
}

/*
 *	Close UDP/IP multicast heartbeat interface
 */
static int
mcast_close(struct hb_media* hbm)
{
	struct mcast_private * mcp;
	int	rc = HA_OK;

	MCASTASSERT(hbm);
	mcp = (struct mcast_private *) hbm->pd;

	if (mcp->rsocket >= 0) {
		if (close(mcp->rsocket) < 0) {
			rc = HA_FAIL;
		}
	}
	if (mcp->wsocket >= 0) {
		if (close(mcp->wsocket) < 0) {
			rc = HA_FAIL;
		}
	}
	return(rc);
}

/*
 * Receive a heartbeat multicast packet from UDP interface
 */

static void *
mcast_read(struct hb_media* hbm, int *lenp)
{
	struct mcast_private *	mcp;
	char			buf[MAXLINE];
	socklen_t		addr_len = sizeof(struct sockaddr);
   	struct sockaddr_in	their_addr; /* connector's addr information */
	int	numbytes;
	void	*pkt;

	MCASTASSERT(hbm);
	mcp = (struct mcast_private *) hbm->pd;
	
	if ((numbytes=recvfrom(mcp->rsocket, buf, MAXLINE-1, 0
			       ,(struct sockaddr *)&their_addr, &addr_len)) < 0) {
		if (errno != EINTR) {
			PILCallLog(LOG, PIL_CRIT, "Error receiving from socket: %s"
			    ,	strerror(errno));
		}
		return NULL;
	}
	/* Avoid possible buffer overruns */
	buf[numbytes] = EOS;
	
	if (Debug >= PKTTRACE) {
		PILCallLog(LOG, PIL_DEBUG, "got %d byte packet from %s"
		    ,	numbytes, inet_ntoa(their_addr.sin_addr));
	}
	if (Debug >= PKTCONTTRACE && numbytes > 0) {
		PILCallLog(LOG, PIL_DEBUG, "%s", buf);
	}
	
	pkt = ha_malloc(numbytes + 1);
	if(!pkt){
		PILCallLog(LOG, PIL_CRIT
		    ,	"Error in allocating memory");
		return(NULL);
	}
	
	memcpy(pkt, buf, numbytes + 1);
	*lenp = numbytes + 1 ;

	return(pkt);
	
	
}

/*
 * Send a heartbeat packet over multicast UDP/IP interface
 */

static int
mcast_write(struct hb_media* hbm, void *pkt, int len)
{
	struct mcast_private *	mcp;
	int			rc;
	
	MCASTASSERT(hbm);
	mcp = (struct mcast_private *) hbm->pd;

	if ((rc=sendto(mcp->wsocket, pkt, len, 0
	,	(struct sockaddr *)&mcp->addr
	,	sizeof(struct sockaddr))) != len) {
		PILCallLog(LOG, PIL_CRIT, "Unable to send mcast packet [%d]: %s"
		,	rc, strerror(errno));
		return(HA_FAIL);
	}
	
	if (Debug >= PKTTRACE) {
		PILCallLog(LOG, PIL_DEBUG, "sent %d bytes to %s"
		    ,	rc, inet_ntoa(mcp->addr.sin_addr));
   	}
	if (Debug >= PKTCONTTRACE) {
		PILCallLog(LOG, PIL_DEBUG, "%s", (const char *)pkt);
   	}
	return(HA_OK);


  return(HA_OK);
  
}

/*
 * Set up socket for sending multicast UDP heartbeats
 */

static int
mcast_make_send_sock(struct hb_media * hbm)
{
	int sockfd;
	struct mcast_private * mcp;
	MCASTASSERT(hbm);
	mcp = (struct mcast_private *) hbm->pd;

	if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
		PILCallLog(LOG, PIL_WARN, "Error getting socket: %s", strerror(errno));
		return(sockfd);
   	}

	if (set_mcast_if(sockfd, mcp->interface) < 0) {
		PILCallLog(LOG, PIL_WARN, "Error setting outbound mcast interface: %s", strerror(errno));
	}

	if (set_mcast_loop(sockfd, mcp->loop) < 0) {
		PILCallLog(LOG, PIL_WARN, "Error setting outbound mcast loopback value: %s", strerror(errno));
	}

	if (set_mcast_ttl(sockfd, mcp->ttl) < 0) {
		PILCallLog(LOG, PIL_WARN, "Error setting outbound mcast TTL: %s", strerror(errno));
	}

	if (fcntl(sockfd,F_SETFD, FD_CLOEXEC)) {
		PILCallLog(LOG, PIL_WARN, "Error setting the close-on-exec flag: %s", strerror(errno));
	}
	return(sockfd);
}

/*
 * Set up socket for listening to heartbeats (UDP multicasts)
 */

#define	MAXBINDTRIES	10
static int
mcast_make_receive_sock(struct hb_media * hbm)
{

	struct mcast_private * mcp;
	int	sockfd;
	int	bindtries;
	int	boundyet=0;
	int	one=1;
	int	rc;
	int	binderr=0;

	MCASTASSERT(hbm);
	mcp = (struct mcast_private *) hbm->pd;

	if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
		PILCallLog(LOG, PIL_CRIT, "Error getting socket");
		return -1;
	}
	/* set REUSEADDR option on socket so you can bind a multicast */
	/* reader to multiple interfaces */
	if(setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, (void *)&one, sizeof(one)) < 0){
		PILCallLog(LOG, PIL_CRIT, "Error setsockopt(SO_REUSEADDR)");
	}        

	/* ripped off from udp.c, if we all use SO_REUSEADDR */
	/* this shouldn't be necessary  */
	/* Try binding a few times before giving up */
	/* Sometimes a process with it open is exiting right now */

	for(bindtries=0; !boundyet && bindtries < MAXBINDTRIES; ++bindtries) {
		rc=bind(sockfd, (struct sockaddr *)&mcp->addr, sizeof(mcp->addr));
		binderr=errno;
		if (rc==0) {
			boundyet=1;
		} else if (rc == -1) {
			if (binderr == EADDRINUSE) {
				PILCallLog(LOG, PIL_CRIT, "Can't bind (EADDRINUSE), "
					"retrying");
				sleep(1);
			} else	{ 
			/* don't keep trying if the error isn't caused by */
			/* the address being in use already...real error */
				break;
			}
		}
	}
	if (!boundyet) {
		if (binderr == EADDRINUSE) {
			/* This happens with multiple udp or ppp interfaces */
			PILCallLog(LOG, PIL_INFO
			,	"Someone already listening on port %d [%s]"
			,	mcp->port
			,	mcp->interface);
			PILCallLog(LOG, PIL_INFO, "multicast read process exiting");
			close(sockfd);
			cleanexit(0);
		} else {
			PILCallLog(LOG, PIL_WARN, "Unable to bind socket. Giving up: %s", strerror(errno));
			close(sockfd);
			return(-1);
		}
	}
	/* join the multicast group...this is what really makes this a */
	/* multicast reader */
	if (join_mcast_group(sockfd, &mcp->mcast, mcp->interface) == -1) {
		PILCallLog(LOG, PIL_CRIT, "Can't join multicast group %s on interface %s",
			inet_ntoa(mcp->mcast), mcp->interface);
		PILCallLog(LOG, PIL_INFO, "multicast read process exiting");
		close(sockfd);
		cleanexit(0);
	}
	if (ANYDEBUG) 
		PILCallLog(LOG, PIL_DEBUG, "Successfully joined multicast group %s on"
			"interface %s", inet_ntoa(mcp->mcast), mcp->interface);
		
	if (fcntl(sockfd,F_SETFD, FD_CLOEXEC)) {
		PILCallLog(LOG, PIL_WARN, "Error setting the close-on-exec flag: %s", strerror(errno));
	}
	return(sockfd);
}

static struct mcast_private *
new_mcast_private(const char *ifn, const char *mcast, u_short port,
		u_char ttl, u_char loop)
{
	struct mcast_private *mcp;

	mcp = MALLOCT(struct mcast_private);
	if (mcp == NULL)  {
		return NULL;
	}

	mcp->interface = (char *)STRDUP(ifn);
	if(mcp->interface == NULL) {
		FREE(mcp);
		return NULL;
	}

	/* Set up multicast address */

	if (inet_pton(AF_INET, mcast, (void *)&mcp->mcast) <= 0) {
		FREE(mcp->interface);
		FREE(mcp);
		return NULL;
	}

	memset(&mcp->addr, 0, sizeof(mcp->addr));	/* zero the struct */
	mcp->addr.sin_family = AF_INET;		/* host byte order */
	mcp->addr.sin_port = htons(port);	/* short, network byte order */
	mcp->addr.sin_addr = mcp->mcast;
	mcp->port = port;
	mcp->wsocket = -1;
	mcp->rsocket = -1;
	mcp->ttl=ttl;
	mcp->loop=loop;
	return(mcp);
}

/* set_mcast_loop takes a boolean flag, loop, which is useful on
 * a writing socket.  with loop enabled (the default on a multicast socket)
 * the outbound packet will get looped back and received by the sending
 * interface, if it is listening for the multicast group and port that the
 * packet was sent to.  Returns 0 on success -1 on failure.
 */
static int set_mcast_loop(int sockfd, u_char loop)
{
	return setsockopt(sockfd, IPPROTO_IP, IP_MULTICAST_LOOP, &loop, sizeof(loop));
}

/* set_mcast_ttl will set the time-to-live value for the writing socket.
 * the socket default is TTL=1.  The TTL is used to limit the scope of the
 * packet and can range from 0-255.  
 * TTL     Scope
 * ----------------------------------------------------------------------
 *    0    Restricted to the same host. Won't be output by any interface.
 *    1    Restricted to the same subnet. Won't be forwarded by a router.
 *  <32    Restricted to the same site, organization or department.
 *  <64    Restricted to the same region.
 * <128    Restricted to the same continent.
 * <255    Unrestricted in scope. Global.
 *
 * Returns 0 on success -1 on failure.
 */
static int
set_mcast_ttl(int sockfd, u_char ttl)
{
	return setsockopt(sockfd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl));
}

/*
 * set_mcast_if takes the name of an interface (i.e. eth0) and then
 * sets that as the interface to use for outbound multicast traffic.
 * If ifname is NULL, then it the OS will assign the interface.
 * Returns 0 on success -1 on faliure.
 */
static int
set_mcast_if(int sockfd, char *ifname)
{
	int rc;
	struct in_addr addr;

	/* Zero out the struct... we only care about the address... */
	memset(&addr, 0, sizeof(addr));

	rc = if_getaddr(ifname, &addr);
	if (rc == -1)
		return -1;
	return setsockopt(sockfd, IPPROTO_IP, IP_MULTICAST_IF
	,	(void*)&addr, sizeof(addr));
}

/* join_mcast_group is used to join a multicast group.  the group is
 * specified by a class D multicast address 224.0.0.0/8 in the in_addr
 * structure passed in as a parameter.  The interface name can be used
 * to "bind" the multicast group to a specific interface (or any
 * interface if ifname is NULL);
 * returns 0 on success, -1 on failure.
 */
static int
join_mcast_group(int sockfd, struct in_addr *addr, char *ifname)
{
	struct ip_mreq	mreq_add;

	memset(&mreq_add, 0, sizeof(mreq_add));
	memcpy(&mreq_add.imr_multiaddr, addr, sizeof(struct in_addr));

	if (ifname) {
		if_getaddr(ifname, &mreq_add.imr_interface);
	}
	return setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (void*)&mreq_add, sizeof(mreq_add));
}

/* if_getaddr gets the ip address from an interface
 * specified by name and places it in addr.
 * returns 0 on success and -1 on failure.
 */
static int
if_getaddr(const char *ifname, struct in_addr *addr)
{
	int	fd;
	struct ifreq	if_info;
	
	if (!addr)
		return -1;

	addr->s_addr = INADDR_ANY;

	memset(&if_info, 0, sizeof(if_info));
	if (ifname) {
		strncpy(if_info.ifr_name, ifname, IFNAMSIZ-1);
	} else {	/* ifname is NULL, so use any address */
		return 0;
	}

	if ((fd=socket(AF_INET, SOCK_DGRAM, 0)) == -1)	{
		PILCallLog(LOG, PIL_CRIT, "Error getting socket");
		return -1;
	}
	if (Debug > 0) {
		PILCallLog(LOG, PIL_DEBUG,	"looking up address for %s"
		,	if_info.ifr_name);
	}
	if (ioctl(fd, SIOCGIFADDR, &if_info) == -1) {
		PILCallLog(LOG, PIL_CRIT, "Error ioctl(SIOCGIFADDR)");
		close(fd);
		return -1;
	}

	/*
	 * This #define w/void cast is to quiet alignment errors on some
	 * platforms (notably Solaris)
	 */
#define SOCKADDR_IN(a)        ((struct sockaddr_in *)((void*)(a)))
 
	memcpy(addr, &(SOCKADDR_IN(&if_info.ifr_addr)->sin_addr)
	,	sizeof(struct in_addr));

	close(fd);
	return 0;
}

/* returns true or false */
static int
is_valid_dev(const char *dev)
{
	int rc=0;
	if (dev) {
		struct in_addr addr;
		if (if_getaddr(dev, &addr) != -1)
			rc = 1;
	}
	return rc;
}

/* returns true or false */
#define MCAST_NET	0xf0000000
#define MCAST_BASE	0xe0000000
static int
is_valid_mcast_addr(const char *addr)
{
	unsigned long mc_addr;

	/* make sure address is in host byte order */
	mc_addr = ntohl(inet_addr(addr));

	if ((mc_addr & MCAST_NET) == MCAST_BASE)
		return 1;

	return 0;
}

/* return port number on success, 0 on failure */
static int
get_port(const char *port, u_short *p)
{
	/* not complete yet */
	*p=(u_short)atoi(port);
	return 0;
}

/* returns ttl on succes, -1 on failure */
static int
get_ttl(const char *ttl, u_char *t)
{
	/* not complete yet */
	*t=(u_char)atoi(ttl);
	return 0;
}

/* returns loop on success, -1 on failure */
static int
get_loop(const char *loop, u_char *l)
{
	/* not complete yet */
	*l=(u_char)atoi(loop);
	return 0;
}

/*
 * $Log: mcast.c,v $
 * Revision 1.15.2.4  2005/01/12 02:25:47  horms
 * Fix gcc-4.0 compile problems (Andreas Jochens)
 *
 * Revision 1.15.2.3  2004/05/12 00:10:14  alan
 * Changed all the HBcomm plugins to use PILCallLog() for logging
 * instead of calling the function pointer directly.
 * Also, in the process fixed several mismatches between arguments
 * and format strings, and a couple of format string vulnerabilities.
 *
 * Revision 1.19  2004/05/11 22:04:35  alan
 * Changed all the HBcomm plugins to use PILCallLog() for logging instead of calling
 * the function pointer directly.
 * Also, in the process fixed several mismatches between arguments and format strings, and
 * a couple of format string vulnerabilities.
 *
 * Revision 1.18  2004/04/28 22:30:29  alan
 * Put in some fixes for extra freeing of memory in the communications plugins.
 *
 * Revision 1.17  2004/03/03 05:31:50  alan
 * Put in Gochun Shi's new netstrings on-the-wire data format code.
 * this allows sending binary data, among many other things!
 *
 * Revision 1.16  2004/02/17 22:11:59  lars
 * Pet peeve removal: _Id et al now gone, replaced with consistent Id header.
 *
 * Revision 1.15  2004/01/21 11:34:15  horms
 * - Replaced numerous malloc + strcpy/strncpy invocations with strdup
 *   * This usually makes the code a bit cleaner
 *   * Also is easier not to make code with potential buffer over-runs
 * - Added STRDUP to pils modules
 * - Removed some spurious MALLOC and FREE redefinitions
 *   _that could never be used_
 * - Make sure the return value of strdup is honoured in error conditions
 *
 * Revision 1.14  2003/02/07 08:37:17  horms
 * Removed inclusion of portability.h from .h files
 * so that it does not need to be installed.
 *
 * Revision 1.13  2003/02/05 09:06:34  horms
 * Lars put a lot of work into making sure that portability.h
 * is included first, everywhere. However this broke a few
 * things when building against heartbeat headers that
 * have been installed (usually somewhere under /usr/include or
 * /usr/local/include).
 *
 * This patch should resolve this problem without undoing all of
 * Lars's hard work.
 *
 * As an asside: I think that portability.h is a virus that has
 * infected all of heartbeat's code and now must also infect all
 * code that builds against heartbeat. I wish that it didn't need
 * to be included all over the place. Especially in headers to
 * be installed on the system. However, I respect Lars's opinion
 * that this is the best way to resolve some weird build problems
 * in the current tree.
 *
 * Revision 1.12  2003/01/31 10:02:09  lars
 * Various small code cleanups:
 * - Lots of "signed vs unsigned" comparison fixes
 * - time_t globally replaced with TIME_T
 * - All seqnos moved to "seqno_t", which defaults to unsigned long
 * - DIMOF() definition centralized to portability.h and typecast to int
 * - EOS define moved to portability.h
 * - dropped inclusion of signal.h from stonith.h, so that sigignore is
 *   properly defined
 *
 * Revision 1.11  2002/10/21 10:17:19  horms
 * hb api clients may now be built outside of the heartbeat tree
 *
 * Revision 1.10  2002/09/19 22:40:18  alan
 * Changed a few error return checks to not print anything and return
 * if an error was encountered.
 * Changed a few debug messages to only print if a strictly positive number
 * of chars was received.
 *
 * Revision 1.9  2002/09/12 03:52:07  alan
 * Fixed up a comment :-(.
 *
 * Revision 1.8  2002/09/12 03:39:45  alan
 * Fixed some logging level names in the code and also
 * fixed an error in the license chosen for a file.
 *
 * Revision 1.7  2002/06/16 06:11:26  alan
 * Put in a couple of changes to the PILS interfaces
 *  - exported license information (name, URL)
 *  - imported malloc/free
 *
 * Revision 1.6  2002/05/01 23:50:35  alan
 * Put in some comments about how the code avoids potential buffer overruns.
 *
 * Revision 1.5  2002/04/13 22:35:08  alan
 * Changed ha_msg_add_nv to take an end pointer to make it safer.
 * Added a length parameter to string2msg so it would be safer.
 * Changed the various networking plugins to use the new string2msg().
 *
 * Revision 1.4  2002/04/09 12:45:36  alan
 * Put in changes to the bcast, mcast and serial code such that
 * interrupted system calls in reads are ignored.
 *
 * Revision 1.3  2002/01/17 15:21:23  alan
 * Put in Ram Pai's patch for the bug in the multicast code.
 *
 * Revision 1.2  2001/09/07 16:18:17  alan
 * Updated ping.c to conform to the new plugin loading system.
 * Changed log messages in bcast, mcast, ping and serial to use the
 * new logging function.
 *
 * Revision 1.1  2001/08/10 17:16:44  alan
 * New code for the new plugin loading system.
 *
 * Revision 1.11  2001/06/23 04:30:26  alan
 * Changed the code to use inet_pton() when it's available, and
 * emulate it when it's not...  Patch was from Chris Wright.
 *
 * Revision 1.10  2001/06/08 04:57:48  alan
 * Changed "config.h" to <portability.h>
 *
 */