path: root/web/attachments/137903-nagiosplug-check_dhcp-unicast.diff

--- ../nplg/plugins/check_dhcp.c	2005-01-28 15:00:58.000000000 +0100
+++ ./plugins/check_dhcp.c	2005-06-08 15:28:58.000000000 +0200
@@ -22,12 +22,18 @@
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
-* $Id: check_dhcp.c,v 1.7 2005/01/25 18:11:21 harpermann Exp $
+*--------------------------------------------------------------------------
+* Unicast mode was originally implemented by Heiti of Boras Kommun with
+* general improvements as well as usability fixes and "forward"-porting by
+* Andreas Ericsson of OP5 AB.
+*--------------------------------------------------------------------------
+*
+* $Id: check_dhcp.c,v 1.9 2005/06/07 15:57:53 exon Exp $
 *
 *****************************************************************************/
 
 const char *progname = "check_dhcp";
-const char *revision = "$Revision: 1.7 $";
+const char *revision = "$Revision: 1.9 $";
 const char *copyright = "2001-2004";
 const char *email = "nagiosplug-devel@lists.sourceforge.net";
 
@@ -64,8 +70,8 @@
 
 #elif defined(__sun__) || defined(__solaris__) || defined(__hpux__)
 
-#define INSAP 22 
-#define OUTSAP 24 
+#define INSAP 22
+#define OUTSAP 24
 
 #include <signal.h>
 #include <ctype.h>
@@ -73,19 +79,17 @@
 #include <sys/poll.h>
 #include <sys/dlpi.h>
 
-#define bcopy(source, destination, length) memcpy(destination, source, length)
-
-#define AREA_SZ 5000		/* buffer length in bytes */ 
+#define AREA_SZ 5000			/* buffer length in bytes */
 static u_long ctl_area[AREA_SZ];
 static u_long dat_area[AREA_SZ];
-static struct strbuf ctl = {AREA_SZ, 0, (char *)ctl_area};
-static struct strbuf dat = {AREA_SZ, 0, (char *)dat_area};
+static struct strbuf ctl = { AREA_SZ, 0, (char *)ctl_area };
+static struct strbuf dat = { AREA_SZ, 0, (char *)dat_area };
 
-#define GOT_CTRL 1 
-#define GOT_DATA 2 
-#define GOT_BOTH 3 
-#define GOT_INTR 4 
-#define GOT_ERR 128 
+#define GOT_CTRL 1
+#define GOT_DATA 2
+#define GOT_BOTH 3
+#define GOT_INTR 4
+#define GOT_ERR 128
 
 #define u_int8_t	 uint8_t
 #define u_int16_t	uint16_t
@@ -97,26 +101,11 @@
 static int put_both(int, int, int, int);
 static int dl_open(const char *, int, int *);
 static int dl_bind(int, int, u_char *);
-long mac_addr_dlpi( const char *, int, u_char *);
+static long mac_addr_dlpi(const char *, int, u_char *);
 
 #endif
 
-#define HAVE_GETOPT_H
-
-
-/**** Common definitions ****/
-
-#define STATE_OK          0
-#define STATE_WARNING     1
-#define STATE_CRITICAL    2
-#define STATE_UNKNOWN     -1
-
-#define OK                0
-#define ERROR             -1
-
-#define FALSE             0
-#define TRUE              1
-
+static int add_requested_server(struct in_addr server_address);
 
 /**** DHCP definitions ****/
 
@@ -126,39 +115,39 @@
 #define MAX_DHCP_OPTIONS_LENGTH          312
 
 
-typedef struct dhcp_packet_struct{
-        u_int8_t  op;                   /* packet type */
-        u_int8_t  htype;                /* type of hardware address for this machine (Ethernet, etc) */
-        u_int8_t  hlen;                 /* length of hardware address (of this machine) */
-        u_int8_t  hops;                 /* hops */
-        u_int32_t xid;                  /* random transaction id number - chosen by this machine */
-        u_int16_t secs;                 /* seconds used in timing */
-        u_int16_t flags;                /* flags */
-        struct in_addr ciaddr;          /* IP address of this machine (if we already have one) */
-        struct in_addr yiaddr;          /* IP address of this machine (offered by the DHCP server) */
-        struct in_addr siaddr;          /* IP address of DHCP server */
-        struct in_addr giaddr;          /* IP address of DHCP relay */
-        unsigned char chaddr [MAX_DHCP_CHADDR_LENGTH];      /* hardware address of this machine */
-        char sname [MAX_DHCP_SNAME_LENGTH];    /* name of DHCP server */
-        char file [MAX_DHCP_FILE_LENGTH];      /* boot file name (used for diskless booting?) */
-	char options[MAX_DHCP_OPTIONS_LENGTH];  /* options */
-        }dhcp_packet;
-
-
-typedef struct dhcp_offer_struct{
-	struct in_addr server_address;   /* address of DHCP server that sent this offer */
-	struct in_addr offered_address;  /* the IP address that was offered to us */
-	u_int32_t lease_time;            /* lease time in seconds */
-	u_int32_t renewal_time;          /* renewal time in seconds */
-	u_int32_t rebinding_time;        /* rebinding time in seconds */
+typedef struct dhcp_packet_struct {
+	u_int8_t op;				/* packet type */
+	u_int8_t htype;				/* type of hardware address for this machine (Ethernet, etc) */
+	u_int8_t hlen;				/* length of hardware address (of this machine) */
+	u_int8_t hops;				/* hops */
+	u_int32_t xid;				/* random transaction id number - chosen by this machine */
+	u_int16_t secs;				/* seconds used in timing */
+	u_int16_t flags;			/* flags */
+	struct in_addr ciaddr;		/* IP address of this machine (if we already have one) */
+	struct in_addr yiaddr;		/* IP address of this machine (offered by the DHCP server) */
+	struct in_addr siaddr;		/* IP address of DHCP server */
+	struct in_addr giaddr;		/* IP address of DHCP relay */
+	unsigned char chaddr[MAX_DHCP_CHADDR_LENGTH];	/* hardware address of this machine */
+	char sname[MAX_DHCP_SNAME_LENGTH];	/* name of DHCP server */
+	char file[MAX_DHCP_FILE_LENGTH];	/* boot file name (used for diskless booting?) */
+	char options[MAX_DHCP_OPTIONS_LENGTH];	/* options */
+} dhcp_packet;
+
+
+typedef struct dhcp_offer_struct {
+	struct in_addr server_address;	/* address of DHCP server that sent this offer */
+	struct in_addr offered_address;	/* the IP address that was offered to us */
+	u_int32_t lease_time;		/* lease time in seconds */
+	u_int32_t renewal_time;		/* renewal time in seconds */
+	u_int32_t rebinding_time;	/* rebinding time in seconds */
 	struct dhcp_offer_struct *next;
-        }dhcp_offer;
+} dhcp_offer;
 
 
-typedef struct requested_server_struct{
+typedef struct requested_server_struct {
 	struct in_addr server_address;
 	struct requested_server_struct *next;
-        }requested_server;
+} requested_server;
 
 
 #define BOOTREQUEST     1
@@ -183,35 +172,40 @@
 #define DHCP_INFINITE_TIME              0xFFFFFFFF
 
 #define DHCP_BROADCAST_FLAG 32768
+#define DHCP_UNICAST_FLAG   0
 
 #define DHCP_SERVER_PORT   67
 #define DHCP_CLIENT_PORT   68
 
-#define ETHERNET_HARDWARE_ADDRESS            1     /* used in htype field of dhcp packet */
-#define ETHERNET_HARDWARE_ADDRESS_LENGTH     6     /* length of Ethernet hardware addresses */
+#define ETH_HW_ADDR            1	/* used in htype field of dhcp packet */
+#define ETH_HW_ADDR_LEN     6	/* length of Ethernet hardware addresses */
 
-unsigned char client_hardware_address[MAX_DHCP_CHADDR_LENGTH]="";
+u_int8_t unicast_hops = 0;   /* number of hops for unicast dhcp */
+struct in_addr my_ip;        /* our address (required for relay) */
+struct in_addr dhcp_ip;      /* server to query (if in unicast mode) */
+struct sockaddr_in *my_addr; /* used to obtain our address */
+unsigned char client_hardware_address[MAX_DHCP_CHADDR_LENGTH] = "";
 
-char network_interface_name[8]="eth0";
+char network_interface_name[8] = "eth0";
 
-u_int32_t packet_xid=0;
+u_int32_t packet_xid = 0;
 
-u_int32_t dhcp_lease_time=0;
-u_int32_t dhcp_renewal_time=0;
-u_int32_t dhcp_rebinding_time=0;
+u_int32_t dhcp_lease_time = 0;
+u_int32_t dhcp_renewal_time = 0;
+u_int32_t dhcp_rebinding_time = 0;
 
-int dhcpoffer_timeout=2;
+int dhcpoffer_timeout = 2;
 
-dhcp_offer *dhcp_offer_list=NULL;
-requested_server *requested_server_list=NULL;
+dhcp_offer *dhcp_offer_list = NULL;
+requested_server *requested_server_list = NULL;
 
-int valid_responses=0;     /* number of valid DHCPOFFERs we received */
-int requested_servers=0;   
-int requested_responses=0;
+int valid_responses = 0;		/* number of valid DHCPOFFERs we received */
+int requested_servers = 0;
+int requested_responses = 0;
 
-int request_specific_address=FALSE;
-int received_requested_address=FALSE;
-int verbose=0;
+int request_specific_address = FALSE;
+int received_requested_address = FALSE;
+int verbose = 0;
 struct in_addr requested_address;
 
 
@@ -221,41 +215,42 @@
 void print_usage(void);
 void print_help(void);
 
-int get_hardware_address(int,char *);
+int get_hardware_address(int, char *);
 
 int send_dhcp_discover(int);
 int get_dhcp_offer(int);
 
 int get_results(void);
 
-int add_dhcp_offer(struct in_addr,dhcp_packet *);
+int add_dhcp_offer(struct in_addr, dhcp_packet *);
 int free_dhcp_offer_list(void);
 int free_requested_server_list(void);
 
 int create_dhcp_socket(void);
-int close_dhcp_socket(int);
-int send_dhcp_packet(void *,int,int,struct sockaddr_in *);
-int receive_dhcp_packet(void *,int,int,int,struct sockaddr_in *);
+int send_dhcp_packet(void *, int, int, struct sockaddr_in *);
+int receive_dhcp_packet(void *, int, int, int, struct sockaddr_in *);
 
 
 
-int main(int argc, char **argv){
+int
+main(int argc, char **argv)
+{
 	int dhcp_socket;
 	int result;
 
-	setlocale (LC_ALL, "");
-	bindtextdomain (PACKAGE, LOCALEDIR);
-	textdomain (PACKAGE);
-	
-	if(process_arguments(argc,argv)!=OK){
-		usage4 (_("Could not parse arguments"));
-		}
+	setlocale(LC_ALL, "");
+	bindtextdomain(PACKAGE, LOCALEDIR);
+	textdomain(PACKAGE);
+
+	if(process_arguments(argc, argv) != OK) {
+		usage4(_("Could not parse arguments"));
+	}
 
 	/* create socket for DHCP communications */
-	dhcp_socket=create_dhcp_socket();
+	dhcp_socket = create_dhcp_socket();
 
 	/* get hardware address of client machine */
-	get_hardware_address(dhcp_socket,network_interface_name);
+	get_hardware_address(dhcp_socket, network_interface_name);
 
 	/* send DHCPDISCOVER packet */
 	send_dhcp_discover(dhcp_socket);
@@ -264,930 +259,967 @@
 	get_dhcp_offer(dhcp_socket);
 
 	/* close socket we created */
-	close_dhcp_socket(dhcp_socket);
+	close(dhcp_socket);
 
 	/* determine state/plugin output to return */
-	result=get_results();
+	result = get_results();
 
 	/* free allocated memory */
 	free_dhcp_offer_list();
 	free_requested_server_list();
 
 	return result;
-        }
-
+}
 
 
 /* determines hardware address on client machine */
-int get_hardware_address(int sock,char *interface_name){
-
+int
+get_hardware_address(int sock, char *interface_name)
+{
 	int i;
 
 #if defined(__linux__)
 	struct ifreq ifr;
 
-	strncpy((char *)&ifr.ifr_name,interface_name,sizeof(ifr.ifr_name));
-	
+	strncpy((char *)&ifr.ifr_name, interface_name, sizeof(ifr.ifr_name));
+
 	/* try and grab hardware address of requested interface */
-	if(ioctl(sock,SIOCGIFHWADDR,&ifr)<0){
-                printf(_("Error: Could not get hardware address of interface '%s'\n"),interface_name);
+	if(ioctl(sock, SIOCGIFHWADDR, &ifr) < 0) {
+		printf(_("Error: Could not get hardware address of interface '%s'\n"),
+			   interface_name);
 		exit(STATE_UNKNOWN);
-	        }
+	}
+	memcpy(&client_hardware_address[0], &ifr.ifr_hwaddr.sa_data, 6);
+
+	/* get the IP of the interface we're using if this is a unicast request */
+	if(unicast_hops) {
+		if(ioctl(sock, SIOCGIFADDR, &ifr) < 0) {
+			printf(_("Error: Could not determine IP-address of interface '%s'\n"),
+				   interface_name);
+			exit(STATE_UNKNOWN);
+		}
 
-	memcpy(&client_hardware_address[0],&ifr.ifr_hwaddr.sa_data,6);
+		/* cast it to avoid black pointer magic */
+		my_addr = (struct sockaddr_in *)&ifr.ifr_addr;
+		my_ip.s_addr = my_addr->sin_addr.s_addr;
+		if(verbose)
+			printf("Pretending to be relay client %s\n", inet_ntoa(my_ip));
+	}
 
 #elif defined(__bsd__)
-						/* King 2004	see ACKNOWLEDGEMENTS */
+	/* King 2004    see ACKNOWLEDGEMENTS */
 
-        int                     mib[6], len;
-        char                    *buf;
-        unsigned char           *ptr;
-        struct if_msghdr        *ifm;
-        struct sockaddr_dl      *sdl;
-
-        mib[0] = CTL_NET;
-        mib[1] = AF_ROUTE;
-        mib[2] = 0;
-        mib[3] = AF_LINK;
-        mib[4] = NET_RT_IFLIST;
-
-        if ((mib[5] = if_nametoindex(interface_name)) == 0) {
-                printf(_("Error: if_nametoindex error - %s.\n"), strerror(errno));
-                exit(STATE_UNKNOWN);
-        }
-
-        if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0) {
-                printf(_("Error: Couldn't get hardware address from %s. sysctl 1 error - %s.\n"), interface_name, strerror(errno));
-                exit(STATE_UNKNOWN);
-        }
-
-        if ((buf = malloc(len)) == NULL) {
-                printf(_("Error: Couldn't get hardware address from interface %s. malloc error - %s.\n"), interface_name, strerror(errno));
-                exit(4);
-        }
-
-        if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
-                printf(_("Error: Couldn't get hardware address from %s. sysctl 2 error - %s.\n"), interface_name, strerror(errno));
-                exit(STATE_UNKNOWN);
-        }
-
-        ifm = (struct if_msghdr *)buf;
-        sdl = (struct sockaddr_dl *)(ifm + 1);
-        ptr = (unsigned char *)LLADDR(sdl);
-        memcpy(&client_hardware_address[0], ptr, 6) ;
-						/* King 2004 */
+	int mib[6], len;
+	char *buf;
+	unsigned char *ptr;
+	struct if_msghdr *ifm;
+	struct sockaddr_dl *sdl;
+
+	mib[0] = CTL_NET;
+	mib[1] = AF_ROUTE;
+	mib[2] = 0;
+	mib[3] = AF_LINK;
+	mib[4] = NET_RT_IFLIST;
+
+	if((mib[5] = if_nametoindex(interface_name)) == 0) {
+		printf(_("Error: if_nametoindex error - %s.\n"), strerror(errno));
+		exit(STATE_UNKNOWN);
+	}
+
+	if(sysctl(mib, 6, NULL, &len, NULL, 0) < 0) {
+		printf(_("Error: Couldn't get hardware address from %s. sysctl 1 error - %s.\n"),
+		       interface_name, strerror(errno));
+		exit(STATE_UNKNOWN);
+	}
+
+	if((buf = malloc(len)) == NULL) {
+		printf(_("Error: Couldn't get hardware address from interface %s. malloc error - %s.\n"),
+		       interface_name, strerror(errno));
+		exit(4);
+	}
+
+	if(sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
+		printf(_("Error: Couldn't get hardware address from %s. sysctl 2 error - %s.\n"),
+		       interface_name, strerror(errno));
+		exit(STATE_UNKNOWN);
+	}
+
+	ifm = (struct if_msghdr *)buf;
+	sdl = (struct sockaddr_dl *)(ifm + 1);
+	ptr = (unsigned char *)LLADDR(sdl);
+	memcpy(&client_hardware_address[0], ptr, 6);
+	/* King 2004 */
 
 #elif defined(__sun__) || defined(__solaris__)
 
-						/* Kompf 2000-2003	see ACKNOWLEDGEMENTS */
+	/* Kompf 2000-2003  see ACKNOWLEDGEMENTS */
 	long stat;
 	char dev[20] = "/dev/";
 	char *p;
 	int unit;
 
-	for (p = interface_name; *p && isalpha(*p); p++)
-		/* no-op */ ;
-	if ( p != '\0' ) {
-		unit = atoi(p) ;
-		*p = '\0' ;
-		strncat(dev, interface_name, 6) ;
-	} else {
-		printf(_("Error: can't find unit number in interface_name (%s) - expecting TypeNumber eg lnc0.\n"), interface_name);
+	for(p = interface_name; *p && isalpha(*p); p++)	/* no-op */ ;
+
+	if(p != '\0') {
+		unit = atoi(p);
+		*p = '\0';
+		strncat(dev, interface_name, 6);
+	}
+	else {
+		printf(_("Error: can't find unit number in interface_name (%s) - expecting TypeNumber eg lnc0.\n"),
+		       interface_name);
 		exit(STATE_UNKNOWN);
 	}
 	stat = mac_addr_dlpi(dev, unit, client_hardware_address);
-	if (stat != 0) {
-		printf(_("Error: can't read MAC address from DLPI streams interface for device %s unit %d.\n"), dev, unit);
+	if(stat != 0) {
+		printf(_("Error: can't read MAC address from DLPI streams interface for device %s unit %d.\n"),
+		       dev, unit);
 		exit(STATE_UNKNOWN);
 	}
 
 #elif defined(__hpux__)
 
 	long stat;
-	char dev[20] = "/dev/dlpi" ;
+	char dev[20] = "/dev/dlpi";
 	int unit = 0;
 
 	stat = mac_addr_dlpi(dev, unit, client_hardware_address);
-	if (stat != 0) {
-		printf(_("Error: can't read MAC address from DLPI streams interface for device %s unit %d.\n"), dev, unit);
+	if(stat != 0) {
+		printf(_("Error: can't read MAC address from DLPI streams interface for device %s unit %d.\n"),
+		       dev, unit);
 		exit(STATE_UNKNOWN);
 	}
-						/* Kompf 2000-2003 */
+	/* Kompf 2000-2003 */
 
 #else
 	printf(_("Error: can't get MAC address for this architecture.\n"));
 	exit(STATE_UNKNOWN);
 #endif
 
-	if (verbose) { 
+	if(verbose) {
 		printf(_("Hardware address: "));
-		for (i=0; i<6; ++i)
+		for(i = 0; i < 6; ++i)
 			printf("%2.2x", client_hardware_address[i]);
-		printf( "\n");
+		printf("\n");
 	}
 
 	return OK;
-        }
+}
 
 
 /* sends a DHCPDISCOVER broadcast message in an attempt to find DHCP servers */
-int send_dhcp_discover(int sock){
+int
+send_dhcp_discover(int sock)
+{
 	dhcp_packet discover_packet;
 	struct sockaddr_in sockaddr_broadcast;
 
 
 	/* clear the packet data structure */
-	bzero(&discover_packet,sizeof(discover_packet));
-
+	memset(&discover_packet, 0, sizeof(discover_packet));
 
 	/* boot request flag (backward compatible with BOOTP servers) */
-	discover_packet.op=BOOTREQUEST;
+	discover_packet.op = BOOTREQUEST;
 
 	/* hardware address type */
-	discover_packet.htype=ETHERNET_HARDWARE_ADDRESS;
+	discover_packet.htype = ETH_HW_ADDR;
 
 	/* length of our hardware address */
-	discover_packet.hlen=ETHERNET_HARDWARE_ADDRESS_LENGTH;
-
-	discover_packet.hops=0;
+	discover_packet.hlen = ETH_HW_ADDR_LEN;
 
-	/* transaction id is supposed to be random */
+	/* transaction id is supposed to be random. We won't use the address so
+	 * we don't care about high entropy here. time() is good enough */
 	srand(time(NULL));
-	packet_xid=random();
-	discover_packet.xid=htonl(packet_xid);
+	packet_xid = random();
+	discover_packet.xid = htonl(packet_xid);
 
 	/**** WHAT THE HECK IS UP WITH THIS?!?  IF I DON'T MAKE THIS CALL, ONLY ONE SERVER RESPONSE IS PROCESSED!!!! ****/
 	/* downright bizzarre... */
 	ntohl(discover_packet.xid);
 
-	/*discover_packet.secs=htons(65535);*/
-	discover_packet.secs=0xFF;
+	/*discover_packet.secs=htons(65535); */
+	discover_packet.secs = 0xFF;
 
-	/* tell server it should broadcast its response */ 
-	discover_packet.flags=htons(DHCP_BROADCAST_FLAG);
+	/* server needs to know if it should broadcast or unicast its response.
+	 * 0x8000L == 32768 == 1 << 15 == broadcast, 0 == unicast */
+	discover_packet.flags = unicast_hops == 0 ? htons(DHCP_BROADCAST_FLAG) : 0;
 
 	/* our hardware address */
-	memcpy(discover_packet.chaddr,client_hardware_address,ETHERNET_HARDWARE_ADDRESS_LENGTH);
+	memcpy(discover_packet.chaddr, client_hardware_address, ETH_HW_ADDR_LEN);
 
 	/* first four bytes of options field is magic cookie (as per RFC 2132) */
-	discover_packet.options[0]='\x63';
-	discover_packet.options[1]='\x82';
-	discover_packet.options[2]='\x53';
-	discover_packet.options[3]='\x63';
+	discover_packet.options[0] = '\x63';
+	discover_packet.options[1] = '\x82';
+	discover_packet.options[2] = '\x53';
+	discover_packet.options[3] = '\x63';
 
 	/* DHCP message type is embedded in options field */
-	discover_packet.options[4]=DHCP_OPTION_MESSAGE_TYPE;    /* DHCP message type option identifier */
-	discover_packet.options[5]='\x01';               /* DHCP message option length in bytes */
-	discover_packet.options[6]=DHCPDISCOVER;
+	discover_packet.options[4] = DHCP_OPTION_MESSAGE_TYPE;	/* DHCP message type option identifier */
+	discover_packet.options[5] = '\x01';	/* DHCP message option length in bytes */
+	discover_packet.options[6] = DHCPDISCOVER;
 
 	/* the IP address we're requesting */
-	if(request_specific_address==TRUE){
-		discover_packet.options[7]=DHCP_OPTION_REQUESTED_ADDRESS;
-		discover_packet.options[8]='\x04';
-		memcpy(&discover_packet.options[9],&requested_address,sizeof(requested_address));
-	        }
-	
-	/* send the DHCPDISCOVER packet to broadcast address */
-        sockaddr_broadcast.sin_family=AF_INET;
-        sockaddr_broadcast.sin_port=htons(DHCP_SERVER_PORT);
-        sockaddr_broadcast.sin_addr.s_addr=INADDR_BROADCAST;
-	bzero(&sockaddr_broadcast.sin_zero,sizeof(sockaddr_broadcast.sin_zero));
+	if(request_specific_address == TRUE) {
+		discover_packet.options[7] = DHCP_OPTION_REQUESTED_ADDRESS;
+		discover_packet.options[8] = '\x04';
+		memcpy(&discover_packet.options[9], &requested_address,
+		       sizeof(requested_address));
+	}
+
+	/* unicast mods goes here */
+	if(unicast_hops)
+		discover_packet.giaddr.s_addr = my_ip.s_addr;
 
+	discover_packet.hops = unicast_hops;
 
-	if (verbose) {
-		printf(_("DHCPDISCOVER to %s port %d\n"),inet_ntoa(sockaddr_broadcast.sin_addr),ntohs(sockaddr_broadcast.sin_port));
-		printf("DHCPDISCOVER XID: %lu (0x%X)\n",ntohl(discover_packet.xid),ntohl(discover_packet.xid));
-		printf("DHCDISCOVER ciaddr:  %s\n",inet_ntoa(discover_packet.ciaddr));
-		printf("DHCDISCOVER yiaddr:  %s\n",inet_ntoa(discover_packet.yiaddr));
-		printf("DHCDISCOVER siaddr:  %s\n",inet_ntoa(discover_packet.siaddr));
-		printf("DHCDISCOVER giaddr:  %s\n",inet_ntoa(discover_packet.giaddr));
+	/* send the DHCPDISCOVER packet to broadcast address */
+	sockaddr_broadcast.sin_family = AF_INET;
+	sockaddr_broadcast.sin_port = htons(DHCP_SERVER_PORT);
+	sockaddr_broadcast.sin_addr.s_addr = unicast_hops == 0 ? INADDR_BROADCAST : dhcp_ip.s_addr;
+	memset(&sockaddr_broadcast.sin_zero, 0, sizeof(sockaddr_broadcast.sin_zero));
+
+
+	if(verbose) {
+		printf(_("DHCPDISCOVER to %s port %d\n"),
+			   inet_ntoa(sockaddr_broadcast.sin_addr),
+			   ntohs(sockaddr_broadcast.sin_port));
+		printf("DHCPDISCOVER XID: %u (0x%X)\n", ntohl(discover_packet.xid),
+			   ntohl(discover_packet.xid));
+		printf("DHCDISCOVER ciaddr:  %s\n", inet_ntoa(discover_packet.ciaddr));
+		printf("DHCDISCOVER yiaddr:  %s\n", inet_ntoa(discover_packet.yiaddr));
+		printf("DHCDISCOVER siaddr:  %s\n", inet_ntoa(discover_packet.siaddr));
+		printf("DHCDISCOVER giaddr:  %s\n", inet_ntoa(discover_packet.giaddr));
 	}
 
 	/* send the DHCPDISCOVER packet out */
-	send_dhcp_packet(&discover_packet,sizeof(discover_packet),sock,&sockaddr_broadcast);
+	send_dhcp_packet(&discover_packet, sizeof(discover_packet), sock,
+					 &sockaddr_broadcast);
 
-	if (verbose) 
-		printf("\n\n");
+	if(verbose) printf("\n\n");
 
 	return OK;
-        }
-
-
+}
 
 
 /* waits for a DHCPOFFER message from one or more DHCP servers */
-int get_dhcp_offer(int sock){
+int
+get_dhcp_offer(int sock)
+{
 	dhcp_packet offer_packet;
 	struct sockaddr_in source;
-	int result=OK;
-	int timeout=1;
-	int responses=0;
+	int result = OK;
+	int responses = 0;
 	int x;
-	time_t start_time;
+	time_t dhcp_start_time;
 	time_t current_time;
 
-	time(&start_time);
+	time(&dhcp_start_time);
 
 	/* receive as many responses as we can */
-	for(responses=0,valid_responses=0;;){
+	for(responses = 0, valid_responses = 0;;) {
 
 		time(&current_time);
-		if((current_time-start_time)>=dhcpoffer_timeout)
+		if((current_time - dhcp_start_time) >= dhcpoffer_timeout)
 			break;
 
-		if (verbose) 
-			printf("\n\n");
+		if(verbose) printf("\n\n");
 
-		bzero(&source,sizeof(source));
-		bzero(&offer_packet,sizeof(offer_packet));
+		memset(&source, 0, sizeof(source));
+		memset(&offer_packet, 0, sizeof(offer_packet));
 
-		result=OK;
-		result=receive_dhcp_packet(&offer_packet,sizeof(offer_packet),sock,dhcpoffer_timeout,&source);
-		
-		if(result!=OK){
-			if (verbose)
-				printf(_("Result=ERROR\n"));
+		result = OK;
+		result = receive_dhcp_packet(&offer_packet, sizeof(offer_packet), sock,
+		                             dhcpoffer_timeout, &source);
 
+		if(result != OK) {
+			if(verbose) printf(_("Result=ERROR\n"));
 			continue;
-		        }
-		else{
-			if (verbose) 
-				printf(_("Result=OK\n"));
-
+		}
+		else {
+			if(verbose) printf(_("Result=OK\n"));
 			responses++;
-		        }
+		}
 
-		if (verbose) {
-			printf(_("DHCPOFFER from IP address %s\n"),inet_ntoa(source.sin_addr));
-			printf("DHCPOFFER XID: %lu (0x%X)\n",ntohl(offer_packet.xid),ntohl(offer_packet.xid));
+		if(verbose) {
+			printf(_("DHCPOFFER from IP address %s\n"), inet_ntoa(source.sin_addr));
+			printf("DHCPOFFER XID: %u (0x%X)\n", ntohl(offer_packet.xid),
+			       ntohl(offer_packet.xid));
 		}
 
 		/* check packet xid to see if its the same as the one we used in the discover packet */
-		if(ntohl(offer_packet.xid)!=packet_xid){
-			if (verbose)
-				printf(_("DHCPOFFER XID (%lu) did not match DHCPDISCOVER XID (%lu) - ignoring packet\n"),ntohl(offer_packet.xid),packet_xid);
-
+		if(ntohl(offer_packet.xid) != packet_xid) {
+			if(verbose)
+				printf(_("DHCPOFFER XID (%u) did not match DHCPDISCOVER XID (%u) - ignoring packet\n"),
+				       ntohl(offer_packet.xid), packet_xid);
 			continue;
-		        }
+		}
 
 		/* check hardware address */
-		result=OK;
-		if (verbose)
-			printf("DHCPOFFER chaddr: ");
-
-		for(x=0;x<ETHERNET_HARDWARE_ADDRESS_LENGTH;x++){
-			if (verbose)
-				printf("%02X",(unsigned char)offer_packet.chaddr[x]);
+		result = OK;
+		if(verbose) printf("DHCPOFFER chaddr: ");
 
-			if(offer_packet.chaddr[x]!=client_hardware_address[x])
-				result=ERROR;
+		for(x = 0; x < ETH_HW_ADDR_LEN; x++) {
+			if(verbose) printf("%02X", (unsigned char)offer_packet.chaddr[x]);
+			if(offer_packet.chaddr[x] != client_hardware_address[x])
+				result = ERROR;
 		}
-		if (verbose)
-			printf("\n");
+		if(verbose) printf("\n");
 
-		if(result==ERROR){
-			if (verbose) 
+		if(result == ERROR) {
+			if(verbose)
 				printf(_("DHCPOFFER hardware address did not match our own - ignoring packet\n"));
-
 			continue;
-		        }
+		}
 
-		if (verbose) {
-			printf("DHCPOFFER ciaddr: %s\n",inet_ntoa(offer_packet.ciaddr));
-			printf("DHCPOFFER yiaddr: %s\n",inet_ntoa(offer_packet.yiaddr));
-			printf("DHCPOFFER siaddr: %s\n",inet_ntoa(offer_packet.siaddr));
-			printf("DHCPOFFER giaddr: %s\n",inet_ntoa(offer_packet.giaddr));
+		if(verbose) {
+			printf("DHCPOFFER ciaddr: %s\n", inet_ntoa(offer_packet.ciaddr));
+			printf("DHCPOFFER yiaddr: %s\n", inet_ntoa(offer_packet.yiaddr));
+			printf("DHCPOFFER siaddr: %s\n", inet_ntoa(offer_packet.siaddr));
+			printf("DHCPOFFER giaddr: %s\n", inet_ntoa(offer_packet.giaddr));
 		}
 
-		add_dhcp_offer(source.sin_addr,&offer_packet);
+		add_dhcp_offer(source.sin_addr, &offer_packet);
 
 		valid_responses++;
-	        }
+	}
 
-	if (verbose) {
-		printf(_("Total responses seen on the wire: %d\n"),responses);
-		printf(_("Valid responses for this machine: %d\n"),valid_responses);
+	if(verbose) {
+		printf(_("Total responses seen on the wire: %d\n"), responses);
+		printf(_("Valid responses for this machine: %d\n"), valid_responses);
 	}
 
 	return OK;
-        }
-
+}
 
 
 /* sends a DHCP packet */
-int send_dhcp_packet(void *buffer, int buffer_size, int sock, struct sockaddr_in *dest){
-	struct sockaddr_in myname;
+int
+send_dhcp_packet(void *buffer, int buffer_size, int sock, struct sockaddr_in *dest)
+{
 	int result;
 
-	result=sendto(sock,(char *)buffer,buffer_size,0,(struct sockaddr *)dest,sizeof(*dest));
+	result = sendto(sock, (char *)buffer, buffer_size, 0, (struct sockaddr *)dest,
+					sizeof(*dest));
 
-	if (verbose) 
-		printf(_("send_dhcp_packet result: %d\n"),result);
+	if(verbose) printf(_("send_dhcp_packet result: %d\n"), result);
 
-	if(result<0)
-		return ERROR;
+	if(result < 0) return ERROR;
 
 	return OK;
-        }
-
+}
 
 
 /* receives a DHCP packet */
-int receive_dhcp_packet(void *buffer, int buffer_size, int sock, int timeout, struct sockaddr_in *address){
-        struct timeval tv;
-        fd_set readfds;
+int
+receive_dhcp_packet(void *buffer, int buffer_size, int sock, int timeout,
+					struct sockaddr_in *address)
+{
+	struct timeval tv;
+	fd_set readfds;
+	fd_set oobfds;
 	int recv_result;
 	socklen_t address_size;
 	struct sockaddr_in source_address;
+	int nfound;
 
+	/* wait for data to arrive (up time timeout) */
+	tv.tv_sec = timeout;
+	tv.tv_usec = 0;
+	FD_ZERO(&readfds);
+	FD_ZERO(&oobfds);
+	FD_SET(sock, &readfds);
+	FD_SET(sock, &oobfds);
+	nfound = select(sock + 1, &readfds, NULL, &oobfds, &tv);
+
+	/* make sure some data has arrived */
+	if(!FD_ISSET(sock, &readfds)) {
+		if(verbose)
+			printf(_("nfound: %d, No (more) data received\n"), nfound);
+		return ERROR;
+	}
 
-        /* wait for data to arrive (up time timeout) */
-        tv.tv_sec=timeout;
-        tv.tv_usec=0;
-        FD_ZERO(&readfds);
-        FD_SET(sock,&readfds);
-        select(sock+1,&readfds,NULL,NULL,&tv);
-
-        /* make sure some data has arrived */
-        if(!FD_ISSET(sock,&readfds)){
-		if (verbose)
-                	printf(_("No (more) data received\n"));
-                return ERROR;
-                }
-
-        else{
-
-		/* why do we need to peek first?  i don't know, its a hack.  without it, the source address of the first packet received was
-		   not being interpreted correctly.  sigh... */
-		bzero(&source_address,sizeof(source_address));
-		address_size=sizeof(source_address);
-                recv_result=recvfrom(sock,(char *)buffer,buffer_size,MSG_PEEK,(struct sockaddr *)&source_address,&address_size);
-		if (verbose)
-			printf("recv_result_1: %d\n",recv_result);
-                recv_result=recvfrom(sock,(char *)buffer,buffer_size,0,(struct sockaddr *)&source_address,&address_size);
-		if (verbose)
-			printf("recv_result_2: %d\n",recv_result);
-
-                if(recv_result==-1){
-			if (verbose) {
-				printf(_("recvfrom() failed, "));
-				printf("errno: (%d) -> %s\n",errno,strerror(errno));
-			}
-                        return ERROR;
-                        }
-		else{
-			if (verbose) {
-				printf(_("receive_dhcp_packet() result: %d\n"),recv_result);
-				printf(_("receive_dhcp_packet() source: %s\n"),inet_ntoa(source_address.sin_addr));
-			}
+	/* why do we need to peek first?  i don't know, its a hack.  without it,
+	 * the source address of the first packet received was not being
+	 * interpreted correctly.  sigh... */
+	memset(&source_address, 0, sizeof(source_address));
+	address_size = sizeof(source_address);
+	recv_result = recvfrom(sock, (char *)buffer, buffer_size, MSG_PEEK,
+	                       (struct sockaddr *)&source_address, &address_size);
+
+	if(verbose) printf("recv_result_1: %d\n", recv_result);
+	recv_result = recvfrom(sock, (char *)buffer, buffer_size, 0,
+	                       (struct sockaddr *)&source_address, &address_size);
+	
+	if(verbose) printf("recv_result_2: %d\n", recv_result);
+
+	if(recv_result == -1) {
+		if(verbose) printf("errno: (%d) -> %s\n", errno, strerror(errno));
+		return ERROR;
+	}
+
+	if(verbose) {
+		printf(_("receive_dhcp_packet() result: %d\n"), recv_result);
+		printf(_("receive_dhcp_packet() source: %s\n"),
+		       inet_ntoa(source_address.sin_addr));
+	}
 
-			memcpy(address,&source_address,sizeof(source_address));
-			return OK;
-		        }
-                }
+	memcpy(address, &source_address, sizeof(source_address));
 
 	return OK;
-        }
+}
 
 
 /* creates a socket for DHCP communication */
-int create_dhcp_socket(void){
-        struct sockaddr_in myname;
+int
+create_dhcp_socket(void)
+{
+	struct sockaddr_in myname;
 	struct ifreq interface;
-        int sock;
-        int flag=1;
+	int sock;
+	int flag = 1;
 
-        /* Set up the address we're going to bind to. */
-	bzero(&myname,sizeof(myname));
-        myname.sin_family=AF_INET;
-        myname.sin_port=htons(DHCP_CLIENT_PORT);
-        myname.sin_addr.s_addr=INADDR_ANY;                 /* listen on any address */
-        bzero(&myname.sin_zero,sizeof(myname.sin_zero));
-
-        /* create a socket for DHCP communications */
-	sock=socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP);
-        if(sock<0){
+	/* Set up the address we're going to bind to. */
+	memset(&myname, 0, sizeof(myname));
+	memset(&myname.sin_zero, 0, sizeof(myname.sin_zero));
+	myname.sin_family = AF_INET;
+	/* listen to dhcp server port if we're in unicast mode */
+	myname.sin_port = htons(unicast_hops == 0 ? DHCP_CLIENT_PORT : DHCP_SERVER_PORT);
+	myname.sin_addr.s_addr = unicast_hops == 0 ? INADDR_ANY : my_ip.s_addr;
+
+	/* create a socket for DHCP communications */
+	sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+	if(sock < 0) {
 		printf(_("Error: Could not create socket!\n"));
 		exit(STATE_UNKNOWN);
-	        }
-
-	if (verbose)
-		printf("DHCP socket: %d\n",sock);
+	}
 
-        /* set the reuse address flag so we don't get errors when restarting */
-        flag=1;
-        if(setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,(char *)&flag,sizeof(flag))<0){
+	/* set the reuse address flag so we don't get errors when restarting */
+	flag = 1;
+	if(setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (char *)&flag, sizeof(flag)) < 0) {
 		printf(_("Error: Could not set reuse address option on DHCP socket!\n"));
 		exit(STATE_UNKNOWN);
-	        }
+	}
 
-        /* set the broadcast option - we need this to listen to DHCP broadcast messages */
-        if(setsockopt(sock,SOL_SOCKET,SO_BROADCAST,(char *)&flag,sizeof flag)<0){
+	/* set the broadcast option - we need this to listen to DHCP broadcast messages */
+	if(setsockopt(sock, SOL_SOCKET, SO_BROADCAST, (char *)&flag, sizeof flag) < 0) {
 		printf(_("Error: Could not set broadcast option on DHCP socket!\n"));
 		exit(STATE_UNKNOWN);
-	        }
+	}
 
 	/* bind socket to interface */
 #if defined(__linux__)
-	strncpy(interface.ifr_ifrn.ifrn_name,network_interface_name,IFNAMSIZ);
-	if(setsockopt(sock,SOL_SOCKET,SO_BINDTODEVICE,(char *)&interface,sizeof(interface))<0){
-		printf(_("Error: Could not bind socket to interface %s.  Check your privileges...\n"),network_interface_name);
+	strncpy(interface.ifr_ifrn.ifrn_name, network_interface_name, IFNAMSIZ);
+	if(setsockopt
+	   (sock, SOL_SOCKET, SO_BINDTODEVICE, (char *)&interface,
+		sizeof(interface)) < 0) {
+		printf(_("Error: Could not bind socket to interface %s.  Check your privileges...\n"),
+		       network_interface_name);
 		exit(STATE_UNKNOWN);
-	        }
+	}
 
 #else
-	strncpy(interface.ifr_name,network_interface_name,IFNAMSIZ);
+	strncpy(interface.ifr_name, network_interface_name, IFNAMSIZ);
 #endif
 
-        /* bind the socket */
-        if(bind(sock,(struct sockaddr *)&myname,sizeof(myname))<0){
-		printf(_("Error: Could not bind to DHCP socket (port %d)!  Check your privileges...\n"),DHCP_CLIENT_PORT);
+	/* bind the socket */
+	if(bind(sock, (struct sockaddr *)&myname, sizeof(myname)) < 0) {
+		printf(_("Error: Could not bind to DHCP socket (port %d)!  Check your privileges...\n"),
+		       DHCP_CLIENT_PORT);
 		exit(STATE_UNKNOWN);
-	        }
-
-        return sock;
-        }
-
-
-/* closes DHCP socket */
-int close_dhcp_socket(int sock){
-
-	close(sock);
+	}
 
-	return OK;
-        }
+	return sock;
+}
 
 
 /* adds a requested server address to list in memory */
-int add_requested_server(struct in_addr server_address){
+static int
+add_requested_server(struct in_addr server_address)
+{
 	requested_server *new_server;
 
-	new_server=(requested_server *)malloc(sizeof(requested_server));
-	if(new_server==NULL)
+	new_server = (requested_server *) malloc(sizeof(requested_server));
+	if(new_server == NULL)
 		return ERROR;
 
-	new_server->server_address=server_address;
+	new_server->server_address = server_address;
 
-	new_server->next=requested_server_list;
-	requested_server_list=new_server;
+	new_server->next = requested_server_list;
+	requested_server_list = new_server;
 
 	requested_servers++;
 
-	if (verbose)
-		printf(_("Requested server address: %s\n"),inet_ntoa(new_server->server_address));
+	if(verbose)
+		printf(_("Requested server address: %s\n"),
+			   inet_ntoa(new_server->server_address));
 
 	return OK;
-        }
+}
 
 
 
 
 /* adds a DHCP OFFER to list in memory */
-int add_dhcp_offer(struct in_addr source,dhcp_packet *offer_packet){
+int
+add_dhcp_offer(struct in_addr source, dhcp_packet * offer_packet)
+{
 	dhcp_offer *new_offer;
 	int x;
 	int y;
 	unsigned option_type;
 	unsigned option_length;
 
-	if(offer_packet==NULL)
-		return ERROR;
+	if(offer_packet == NULL) return ERROR;
 
 	/* process all DHCP options present in the packet */
-	for(x=4;x<MAX_DHCP_OPTIONS_LENGTH;){
+	for(x = 4; x < MAX_DHCP_OPTIONS_LENGTH;) {
 
 		/* end of options (0 is really just a pad, but bail out anyway) */
-		if((int)offer_packet->options[x]==-1 || (int)offer_packet->options[x]==0)
+		if((int)offer_packet->options[x] == -1 || (int)offer_packet->options[x] == 0)
 			break;
 
 		/* get option type */
-		option_type=offer_packet->options[x++];
+		option_type = offer_packet->options[x++];
 
 		/* get option length */
-		option_length=offer_packet->options[x++];
+		option_length = offer_packet->options[x++];
 
-		if (verbose) 
-			printf("Option: %d (0x%02X)\n",option_type,option_length);
+		if(verbose)
+			printf("Option: %d (0x%02X)\n", option_type, option_length);
 
 		/* get option data */
-        if(option_type==DHCP_OPTION_LEASE_TIME) {
-            memcpy(&dhcp_lease_time, &offer_packet->options[x],
-                sizeof(dhcp_lease_time));
-            dhcp_lease_time = ntohl(dhcp_lease_time);
-        }
-        if(option_type==DHCP_OPTION_RENEWAL_TIME) {
-            memcpy(&dhcp_renewal_time, &offer_packet->options[x],
-                sizeof(dhcp_renewal_time));
-            dhcp_renewal_time = ntohl(dhcp_renewal_time);
-        }
-        if(option_type==DHCP_OPTION_REBINDING_TIME) {
-            memcpy(&dhcp_rebinding_time, &offer_packet->options[x],
-                sizeof(dhcp_rebinding_time));
-            dhcp_rebinding_time = ntohl(dhcp_rebinding_time);
-        }
+		if(option_type == DHCP_OPTION_LEASE_TIME) {
+			memcpy(&dhcp_lease_time, &offer_packet->options[x],
+			       sizeof(dhcp_lease_time));
+			dhcp_lease_time = ntohl(dhcp_lease_time);
+		}
+		if(option_type == DHCP_OPTION_RENEWAL_TIME) {
+			memcpy(&dhcp_renewal_time, &offer_packet->options[x],
+			       sizeof(dhcp_renewal_time));
+			dhcp_renewal_time = ntohl(dhcp_renewal_time);
+		}
+		if(option_type == DHCP_OPTION_REBINDING_TIME) {
+			memcpy(&dhcp_rebinding_time, &offer_packet->options[x],
+			       sizeof(dhcp_rebinding_time));
+			dhcp_rebinding_time = ntohl(dhcp_rebinding_time);
+		}
 
 		/* skip option data we're ignoring */
-		else
-			for(y=0;y<option_length;y++,x++);
-	        }
+		else for(y = 0; y < option_length; y++, x++) ;
+	}
 
-	if (verbose) {
-		if(dhcp_lease_time==DHCP_INFINITE_TIME)
+	if(verbose) {
+		if(dhcp_lease_time == DHCP_INFINITE_TIME)
 			printf(_("Lease Time: Infinite\n"));
 		else
-			printf(_("Lease Time: %lu seconds\n"),(unsigned long)dhcp_lease_time);
-		if(dhcp_renewal_time==DHCP_INFINITE_TIME)
+			printf(_("Lease Time: %lu seconds\n"), (unsigned long)dhcp_lease_time);
+		if(dhcp_renewal_time == DHCP_INFINITE_TIME)
 			printf(_("Renewal Time: Infinite\n"));
 		else
-			printf(_("Renewal Time: %lu seconds\n"),(unsigned long)dhcp_renewal_time);
-		if(dhcp_rebinding_time==DHCP_INFINITE_TIME)
+			printf(_("Renewal Time: %lu seconds\n"),
+			       (unsigned long)dhcp_renewal_time);
+		if(dhcp_rebinding_time == DHCP_INFINITE_TIME)
 			printf(_("Rebinding Time: Infinite\n"));
-		printf(_("Rebinding Time: %lu seconds\n"),(unsigned long)dhcp_rebinding_time);
+		printf(_("Rebinding Time: %lu seconds\n"),
+		       (unsigned long)dhcp_rebinding_time);
 	}
 
-	new_offer=(dhcp_offer *)malloc(sizeof(dhcp_offer));
+	new_offer = (dhcp_offer *) malloc(sizeof(dhcp_offer));
 
-	if(new_offer==NULL)
-		return ERROR;
+	if(new_offer == NULL) return ERROR;
 
-	new_offer->server_address=source;
-	new_offer->offered_address=offer_packet->yiaddr;
-	new_offer->lease_time=dhcp_lease_time;
-	new_offer->renewal_time=dhcp_renewal_time;
-	new_offer->rebinding_time=dhcp_rebinding_time;
+	new_offer->server_address = source;
+	new_offer->offered_address = offer_packet->yiaddr;
+	new_offer->lease_time = dhcp_lease_time;
+	new_offer->renewal_time = dhcp_renewal_time;
+	new_offer->rebinding_time = dhcp_rebinding_time;
 
 
-	if (verbose) {
-		printf(_("Added offer from server @ %s"),inet_ntoa(new_offer->server_address));
-		printf(_(" of IP address %s\n"),inet_ntoa(new_offer->offered_address));
+	if(verbose) {
+		printf(_("Added offer from server @ %s"),
+		       inet_ntoa(new_offer->server_address));
+		printf(_(" of IP address %s\n"), inet_ntoa(new_offer->offered_address));
 	}
 
 	/* add new offer to head of list */
-	new_offer->next=dhcp_offer_list;
-	dhcp_offer_list=new_offer;
+	new_offer->next = dhcp_offer_list;
+	dhcp_offer_list = new_offer;
 
 	return OK;
-        }
+}
 
 
 /* frees memory allocated to DHCP OFFER list */
-int free_dhcp_offer_list(void){
+int
+free_dhcp_offer_list(void)
+{
 	dhcp_offer *this_offer;
 	dhcp_offer *next_offer;
 
-	for(this_offer=dhcp_offer_list;this_offer!=NULL;this_offer=next_offer){
-		next_offer=this_offer->next;
+	for(this_offer = dhcp_offer_list; this_offer != NULL; this_offer = next_offer) {
+		next_offer = this_offer->next;
 		free(this_offer);
-	        }
+	}
 
 	return OK;
-        }
+}
 
 
 /* frees memory allocated to requested server list */
-int free_requested_server_list(void){
+int
+free_requested_server_list(void)
+{
 	requested_server *this_server;
 	requested_server *next_server;
 
-	for(this_server=requested_server_list;this_server!=NULL;this_server=next_server){
-		next_server=this_server->next;
+	for(this_server = requested_server_list; this_server != NULL;
+		this_server = next_server) {
+		next_server = this_server->next;
 		free(this_server);
-	        }
-	
+	}
+
 	return OK;
-        }
+}
 
 
 /* gets state and plugin output to return */
-int get_results(void){
+int
+get_results(void)
+{
 	dhcp_offer *temp_offer;
 	requested_server *temp_server;
 	int result;
-	u_int32_t max_lease_time=0;
+	u_int32_t max_lease_time = 0;
 
-	received_requested_address=FALSE;
+	received_requested_address = FALSE;
 
 	/* checks responses from requested servers */
-	requested_responses=0;
-	if(requested_servers>0){
+	requested_responses = 0;
+	if(requested_servers > 0) {
 
-		for(temp_server=requested_server_list;temp_server!=NULL;temp_server=temp_server->next){
+		for(temp_server = requested_server_list; temp_server != NULL;
+			temp_server = temp_server->next) {
 
-			for(temp_offer=dhcp_offer_list;temp_offer!=NULL;temp_offer=temp_offer->next){
+			for(temp_offer = dhcp_offer_list; temp_offer != NULL;
+				temp_offer = temp_offer->next) {
 
 				/* get max lease time we were offered */
-				if(temp_offer->lease_time>max_lease_time || temp_offer->lease_time==DHCP_INFINITE_TIME)
-					max_lease_time=temp_offer->lease_time;
-				
+				if(temp_offer->lease_time > max_lease_time
+				   || temp_offer->lease_time == DHCP_INFINITE_TIME)
+					max_lease_time = temp_offer->lease_time;
+
 				/* see if we got the address we requested */
-				if(!memcmp(&requested_address,&temp_offer->offered_address,sizeof(requested_address)))
-					received_requested_address=TRUE;
+				if(!memcmp(&requested_address, &temp_offer->offered_address,
+				           sizeof(requested_address)))
+					received_requested_address = TRUE;
 
 				/* see if the servers we wanted a response from talked to us or not */
-				if(!memcmp(&temp_offer->server_address,&temp_server->server_address,sizeof(temp_server->server_address))){
-	if (verbose) {
-					printf(_("DHCP Server Match: Offerer=%s"),inet_ntoa(temp_offer->server_address));
-					printf(_(" Requested=%s\n"),inet_ntoa(temp_server->server_address));
-	}				       
+				if(!memcmp(&temp_offer->server_address, &temp_server->server_address,
+						   sizeof(temp_server->server_address)))
+				{
+					if(verbose) {
+						printf(_("DHCP Server Match: Offerer=%s"),
+							   inet_ntoa(temp_offer->server_address));
+						printf(_(" Requested=%s\n"),
+							   inet_ntoa(temp_server->server_address));
+					}
 					requested_responses++;
-				        }
-		                }
-		        }
-
-	        }
+				}
+			}
+		}
+	}
 
 	/* else check and see if we got our requested address from any server */
-	else{
-
-		for(temp_offer=dhcp_offer_list;temp_offer!=NULL;temp_offer=temp_offer->next){
-
+	else {
+		for(temp_offer = dhcp_offer_list; temp_offer != NULL;
+			temp_offer = temp_offer->next)
+		{
 			/* get max lease time we were offered */
-			if(temp_offer->lease_time>max_lease_time || temp_offer->lease_time==DHCP_INFINITE_TIME)
-				max_lease_time=temp_offer->lease_time;
-				
+			if(temp_offer->lease_time > max_lease_time
+			   || temp_offer->lease_time == DHCP_INFINITE_TIME)
+				max_lease_time = temp_offer->lease_time;
+
 			/* see if we got the address we requested */
-			if(!memcmp(&requested_address,&temp_offer->offered_address,sizeof(requested_address)))
-				received_requested_address=TRUE;
-	                }
-	        }
-
-	result=STATE_OK;
-	if(valid_responses==0)
-		result=STATE_CRITICAL;
-	else if(requested_servers>0 && requested_responses==0)
-		result=STATE_CRITICAL;
-	else if(requested_responses<requested_servers)
-		result=STATE_WARNING;
-	else if(request_specific_address==TRUE && received_requested_address==FALSE)
-		result=STATE_WARNING;
+			if(!memcmp(&requested_address, &temp_offer->offered_address,
+			           sizeof(requested_address)))
+				received_requested_address = TRUE;
+		}
+	}
 
+	result = STATE_OK;
+	if(valid_responses == 0)
+		result = STATE_CRITICAL;
+	else if(requested_servers > 0 && requested_responses == 0)
+		result = STATE_CRITICAL;
+	else if(requested_responses < requested_servers)
+		result = STATE_WARNING;
+	else if(request_specific_address == TRUE && received_requested_address == FALSE)
+		result = STATE_WARNING;
 
-	printf("DHCP %s: ",(result==STATE_OK)?"ok":"problem");
+	printf("DHCP %s: ", (result == STATE_OK) ? "ok" : "problem");
 
 	/* we didn't receive any DHCPOFFERs */
-	if(dhcp_offer_list==NULL){
+	if(dhcp_offer_list == NULL) {
 		printf(_("No DHCPOFFERs were received.\n"));
 		return result;
-	        }
-
-	printf(_("Received %d DHCPOFFER(s)"),valid_responses);
+	}
 
-	if(requested_servers>0)
-		printf(_(", %s%d of %d requested servers responded"),((requested_responses<requested_servers) && requested_responses>0)?"only ":"",requested_responses,requested_servers);
+	printf(_("Received %d DHCPOFFER(s)"), valid_responses);
 
-	if(request_specific_address==TRUE)
-		printf(_(", requested address (%s) was %soffered"),inet_ntoa(requested_address),(received_requested_address==TRUE)?"":_("not "));
+	if(requested_servers > 0)
+		printf(_(", %s%d of %d requested servers responded"),
+		       ((requested_responses < requested_servers)
+		        && requested_responses > 0) ? "only " : "",
+		       requested_responses,
+		       requested_servers);
+
+	if(request_specific_address == TRUE)
+		printf(_(", requested address (%s) was %soffered"),
+		       inet_ntoa(requested_address),
+		       (received_requested_address == TRUE) ? "" : _("not "));
 
 	printf(_(", max lease time = "));
-	if(max_lease_time==DHCP_INFINITE_TIME)
+	if(max_lease_time == DHCP_INFINITE_TIME)
 		printf(_("Infinity"));
 	else
-		printf("%lu sec",(unsigned long)max_lease_time);
+		printf("%lu sec", (unsigned long)max_lease_time);
 
-	printf(".\n");
+	puts(".");
 
 	return result;
-        }
+}
 
 
 /* process command-line arguments */
-int process_arguments(int argc, char **argv){
-	int c;
-
-	if(argc<1)
-		return ERROR;
-
-	c=0;
-	while((c+=(call_getopt(argc-c,&argv[c])))<argc){
-
-		/*
-		if(is_option(argv[c]))
-			continue;
-		*/
-		}
-
-	return validate_arguments();
-        }
-
-
-
-int call_getopt(int argc, char **argv){
-	int c=0;
-	int i=0;
+int
+process_arguments(int argc, char **argv)
+{
+	int c = 0;
 	struct in_addr ipaddress;
-
-#ifdef HAVE_GETOPT_H
 	int option_index = 0;
-	static struct option long_options[] =
-	{ 
-		{"serverip",       required_argument,0,'s'},
-		{"requestedip",    required_argument,0,'r'},
-		{"timeout",        required_argument,0,'t'},
-		{"interface",      required_argument,0,'i'},
-		{"verbose",        no_argument,      0,'v'},
-		{"version",        no_argument,      0,'V'},
-		{"help",           no_argument,      0,'h'},
-		{0,0,0,0}
-	};
-#endif
 
-	while(1){
-#ifdef HAVE_GETOPT_H
-		c=getopt_long(argc,argv,"+hVvt:s:r:t:i:",long_options,&option_index);
-#else
-		c=getopt(argc,argv,"+?hVvt:s:r:t:i:");
-#endif
+	static struct option long_options[] = {
+		{"host", required_argument, 0, 'H'},
+		{"serverip", required_argument, 0, 's'},
+		{"requestedip", required_argument, 0, 'r'},
+		{"timeout", required_argument, 0, 't'},
+		{"interface", required_argument, 0, 'i'},
+		{"unicast", required_argument, 0, 'u'},
+		{"verbose", no_argument, 0, 'v'},
+		{"version", no_argument, 0, 'V'},
+		{"help", no_argument, 0, 'h'},
+		{0, 0, 0, 0}
+	};
 
-		i++;
+	while(1) {
+		c = getopt_long(argc, argv, "+hVvt:s:r:t:i:u:", long_options, &option_index);
 
-		if(c==-1||c==EOF||c==1)
+		if(c == -1 || c == EOF || c == 1)
 			break;
 
-		switch(c){
-		case 'w':
-		case 'r':
-		case 't':
-		case 'i':
-			i++;
+		switch (c) {
+		case 'u':
+			unicast_hops = (u_int8_t)strtoul(optarg, NULL, 0);
 			break;
-		default:
-			break;
-		        }
-
-		switch(c){
-
-		case 's': /* DHCP server address */
-			if(inet_aton(optarg,&ipaddress))
+		case 's': case 'H': /* DHCP server address */
+			if(inet_aton(optarg, &ipaddress))
 				add_requested_server(ipaddress);
 			/*
-			else
-				usage("Invalid server IP address\n");
-			*/
+			   else
+			   usage("Invalid server IP address\n");
+			 */
+			inet_aton(optarg, &dhcp_ip);
+			if(verbose)
+				printf("querying %s\n", inet_ntoa(dhcp_ip));
 			break;
 
-		case 'r': /* address we are requested from DHCP servers */
-			if(inet_aton(optarg,&ipaddress)){
-				requested_address=ipaddress;
-				request_specific_address=TRUE;
-			        }
+		case 'r':			/* address we are requested from DHCP servers */
+			if(inet_aton(optarg, &ipaddress)) {
+				requested_address = ipaddress;
+				request_specific_address = TRUE;
+			}
 			/*
-			else
-				usage("Invalid requested IP address\n");
-			*/
+			   else
+			   usage("Invalid requested IP address\n");
+			 */
 			break;
 
-		case 't': /* timeout */
-
+		case 't':			/* timeout */
 			/*
-			if(is_intnonneg(optarg))
-			*/
-			if(atoi(optarg)>0)
-				dhcpoffer_timeout=atoi(optarg);
+			   if(is_intnonneg(optarg))
+			 */
+			if(atoi(optarg) > 0)
+				dhcpoffer_timeout = atoi(optarg);
 			/*
-			else
-				usage("Time interval must be a nonnegative integer\n");
-			*/
+			   else
+			   usage("Time interval must be a nonnegative integer\n");
+			 */
 			break;
 
-		case 'i': /* interface name */
-
-			strncpy(network_interface_name,optarg,sizeof(network_interface_name)-1);
-			network_interface_name[sizeof(network_interface_name)-1]='\x0';
-
+		case 'i':			/* interface name */
+			strncpy(network_interface_name, optarg,
+			        sizeof(network_interface_name) - 1);
+			network_interface_name[sizeof(network_interface_name) - 1] = '\x0';
 			break;
 
-		case 'V': /* version */
-			print_revision(progname,revision);
+		case 'V':			/* version */
+			print_revision(progname, revision);
 			exit(STATE_OK);
 
-		case 'h': /* help */
+		case 'h':			/* help */
 			print_help();
 			exit(STATE_OK);
 
-		case 'v': /* verbose */
-			verbose=1;
+		case 'v':			/* verbose */
+			verbose++;
 			break;
 
-		case '?': /* help */
-			usage2 (_("Unknown argument"), optarg);
+		case '?':			/* help */
+			usage2(_("Unknown argument"), optarg);
 			break;
 
 		default:
 			break;
-		        }
-	        }
-
-	return i;
-        }
+		}
+	}
+	
+	return validate_arguments();
+}
 
 
-int validate_arguments(void){
+int
+validate_arguments(void)
+{
 
 	return OK;
-        }
+}
 
 #if defined(__sun__) || defined(__solaris__) || defined(__hpux__)
 
-						/* Kompf 2000-2003	see ACKNOWLEDGEMENTS */
+						/* Kompf 2000-2003  see ACKNOWLEDGEMENTS */
 
 /* get a message from a stream; return type of message */
-static int get_msg(int fd)
+static int
+get_msg(int fd)
 {
-    int flags = 0;
-    int res, ret;
-    ctl_area[0] = 0;
-    dat_area[0] = 0;
-    ret = 0;
-    res = getmsg(fd, &ctl, &dat, &flags);
-
-    if(res < 0) {
-        if(errno == EINTR) {
-            return(GOT_INTR);
-        } else {
-	    printf("%s\n", "get_msg FAILED.");
-            return(GOT_ERR);
-        }
-    }
-    if(ctl.len > 0) {
-        ret |= GOT_CTRL;
-    }
-    if(dat.len > 0) {
-        ret |= GOT_DATA;
-    }
-    return(ret);
+	int flags = 0;
+	int res, ret;
+
+	ctl_area[0] = 0;
+	dat_area[0] = 0;
+	ret = 0;
+	res = getmsg(fd, &ctl, &dat, &flags);
+
+	if(res < 0) {
+		if(errno == EINTR) {
+			return (GOT_INTR);
+		}
+		else {
+			printf("%s\n", "get_msg FAILED.");
+			return (GOT_ERR);
+		}
+	}
+	if(ctl.len > 0) {
+		ret |= GOT_CTRL;
+	}
+	if(dat.len > 0) {
+		ret |= GOT_DATA;
+	}
+	return (ret);
 }
 
 /* verify that dl_primitive in ctl_area = prim */
-static int check_ctrl(int prim)
+static int
+check_ctrl(int prim)
 {
-    dl_error_ack_t *err_ack = (dl_error_ack_t *)ctl_area;
-    if(err_ack->dl_primitive != prim) {
-	printf(_("Error: DLPI stream API failed to get MAC in check_ctrl: %s.\n"), strerror(errno));
-        exit(STATE_UNKNOWN);
-    }
-    return 0;
+	dl_error_ack_t *err_ack = (dl_error_ack_t *) ctl_area;
+
+	if(err_ack->dl_primitive != prim) {
+		printf(_("Error: DLPI stream API failed to get MAC in check_ctrl: %s.\n"),
+		       strerror(errno));
+		exit(STATE_UNKNOWN);
+	}
+	return 0;
 }
 
 /* put a control message on a stream */
-static int put_ctrl(int fd, int len, int pri)
+static int
+put_ctrl(int fd, int len, int pri)
 {
-    ctl.len = len;
-    if(putmsg(fd, &ctl, 0, pri) < 0) {
-	printf(_("Error: DLPI stream API failed to get MAC in put_ctrl/putmsg(): %s.\n"), strerror(errno));
-        exit(STATE_UNKNOWN);
-    }
-    return  0;
+	ctl.len = len;
+	if(putmsg(fd, &ctl, 0, pri) < 0) {
+		printf(_("Error: DLPI stream API failed to get MAC in put_ctrl/putmsg(): %s.\n"),
+		       strerror(errno));
+		exit(STATE_UNKNOWN);
+	}
+
+	return 0;
 }
 
+
 /* put a control + data message on a stream */
-static int put_both(int fd, int clen, int dlen, int pri)
+static int
+put_both(int fd, int clen, int dlen, int pri)
 {
-    ctl.len = clen;
-    dat.len = dlen;
-    if(putmsg(fd, &ctl, &dat, pri) < 0) {
-	printf(_("Error: DLPI stream API failed to get MAC in put_both/putmsg().\n"), strerror(errno));
-        exit(STATE_UNKNOWN);
-    }
-    return  0;
+	ctl.len = clen;
+	dat.len = dlen;
+	if(putmsg(fd, &ctl, &dat, pri) < 0) {
+		printf(_("Error: DLPI stream API failed to get MAC in put_both/putmsg().\n"),
+			   strerror(errno));
+		exit(STATE_UNKNOWN);
+	}
+
+	return 0;
 }
 
+
 /* open file descriptor and attach */
-static int dl_open(const char *dev, int unit, int *fd)
+static int
+dl_open(const char *dev, int unit, int *fd)
 {
-    dl_attach_req_t *attach_req = (dl_attach_req_t *)ctl_area;
-    if((*fd = open(dev, O_RDWR)) == -1) {
-	printf(_("Error: DLPI stream API failed to get MAC in dl_attach_req/open(%s..): %s.\n"), dev, strerror(errno));
-        exit(STATE_UNKNOWN);
-    }
-    attach_req->dl_primitive = DL_ATTACH_REQ;
-    attach_req->dl_ppa = unit;
-    put_ctrl(*fd, sizeof(dl_attach_req_t), 0);
-    get_msg(*fd);
-    return check_ctrl(DL_OK_ACK);
+	dl_attach_req_t *attach_req = (dl_attach_req_t *) ctl_area;
+
+	if((*fd = open(dev, O_RDWR)) == -1) {
+		printf(_
+			   ("Error: DLPI stream API failed to get MAC in dl_attach_req/open(%s..): %s.\n"),
+			   dev, strerror(errno));
+		exit(STATE_UNKNOWN);
+	}
+	attach_req->dl_primitive = DL_ATTACH_REQ;
+	attach_req->dl_ppa = unit;
+	put_ctrl(*fd, sizeof(dl_attach_req_t), 0);
+	get_msg(*fd);
+	return check_ctrl(DL_OK_ACK);
 }
 
+
 /* send DL_BIND_REQ */
-static int dl_bind(int fd, int sap, u_char *addr)
+static int
+dl_bind(int fd, int sap, u_char * addr)
 {
-    dl_bind_req_t *bind_req = (dl_bind_req_t *)ctl_area;
-    dl_bind_ack_t *bind_ack = (dl_bind_ack_t *)ctl_area;
-    bind_req->dl_primitive = DL_BIND_REQ;
-    bind_req->dl_sap = sap;
-    bind_req->dl_max_conind = 1;
-    bind_req->dl_service_mode = DL_CLDLS;
-    bind_req->dl_conn_mgmt = 0;
-    bind_req->dl_xidtest_flg = 0;
-    put_ctrl(fd, sizeof(dl_bind_req_t), 0);
-    get_msg(fd);
-    if (GOT_ERR == check_ctrl(DL_BIND_ACK)) {
-	printf(_("Error: DLPI stream API failed to get MAC in dl_bind/check_ctrl(): %s.\n"), strerror(errno));
-        exit(STATE_UNKNOWN);
-    }
-    bcopy((u_char *)bind_ack + bind_ack->dl_addr_offset, addr,
-        bind_ack->dl_addr_length);
-    return 0;
+	dl_bind_req_t *bind_req = (dl_bind_req_t *) ctl_area;
+	dl_bind_ack_t *bind_ack = (dl_bind_ack_t *) ctl_area;
+
+	bind_req->dl_primitive = DL_BIND_REQ;
+	bind_req->dl_sap = sap;
+	bind_req->dl_max_conind = 1;
+	bind_req->dl_service_mode = DL_CLDLS;
+	bind_req->dl_conn_mgmt = 0;
+	bind_req->dl_xidtest_flg = 0;
+	put_ctrl(fd, sizeof(dl_bind_req_t), 0);
+	get_msg(fd);
+	if(GOT_ERR == check_ctrl(DL_BIND_ACK)) {
+		printf(_
+			   ("Error: DLPI stream API failed to get MAC in dl_bind/check_ctrl(): %s.\n"),
+			   strerror(errno));
+		exit(STATE_UNKNOWN);
+	}
+	memcpy(addr, (u_char *) bind_ack + bind_ack->dl_addr_offset,
+		   bind_ack->dl_addr_length);
+	return 0;
 }
 
+
 /***********************************************************************
  * interface:
  * function mac_addr_dlpi - get the mac address of the interface with 
@@ -1197,37 +1229,39 @@
  *
  * return: 0 if OK, -1 if the address could not be determined
  *
- *
  ***********************************************************************/
 
-long mac_addr_dlpi( const char *dev, int unit, u_char  *addr) {
+long
+mac_addr_dlpi(const char *dev, int unit, u_char * addr)
+{
 
 	int fd;
 	u_char mac_addr[25];
 
-	if (GOT_ERR != dl_open(dev, unit, &fd)) {
-        	if (GOT_ERR != dl_bind(fd, INSAP, mac_addr)) {
-                	bcopy( mac_addr, addr, 6);
-                	return 0;
-                }
+	if(GOT_ERR != dl_open(dev, unit, &fd)) {
+		if(GOT_ERR != dl_bind(fd, INSAP, mac_addr)) {
+			memcpy(addr, mac_addr, 6);
+			return 0;
+		}
 	}
-        close(fd);
+	close(fd);
 	return -1;
 }
 
 						/* Kompf 2000-2003 */
-
 #endif
 
 
 /* print usage help */
-void print_help(void){
+void
+print_help(void)
+{
 
-	print_revision(progname,revision);
+	print_revision(progname, revision);
 
 	printf("Copyright (c) 2001-2004 Ethan Galstad (nagios@nagios.org)\n\n");
-	printf (COPYRIGHT, copyright, email);
-	
+	printf(COPYRIGHT, copyright, email);
+
 	printf(_("This plugin tests the availability of DHCP servers on a network.\n\n"));
 
 	print_usage();
@@ -1241,6 +1275,8 @@
    Seconds to wait for DHCPOFFER before timeout occurs\n\
  -i, --interface=STRING\n\
    Interface to to use for listening (i.e. eth0)\n\
+ -u, --unicast=INTEGER\n\
+   Unicast testing. Requires -s. Useful for testing servers on remote networks.
  -v, --verbose\n\
    Print extra information (command-line use only)\n\
  -h, --help\n\
@@ -1250,12 +1286,10 @@
 }
 
 
-void print_usage(void)
+void
+print_usage(void)
 {
 	printf("\
 Usage: %s [-s serverip] [-r requestedip] [-t timeout] [-i interface]\n\
-                  [-v]",progname);
+                  [-v]", progname);
 }
-
-
-