moved to /plugins (core plugin)

git-svn-id: https://nagiosplug.svn.sourceforge.net/svnroot/nagiosplug/nagiosplug/trunk@1103 f882894a-f735-0410-b71e-b25c423dba1c

contrib/check_dhcp.c

@@ -1,1001 +0,0 @@
-/******************************************************************************
-*
-* CHECK_DHCP.C
-*
-* Program: DHCP plugin for Nagios
-* License: GPL
-* Copyright (c) 2001-2004 Ethan Galstad (nagios@nagios.org)
-*
-* License Information:
-*
-* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
-*
-*****************************************************************************/
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <errno.h>
-#include <unistd.h>
-#include <sys/time.h>
-#include <sys/ioctl.h>
-#include <fcntl.h>
-#include <features.h>
-#include <linux/if_ether.h>
-#include <getopt.h>
-#include <net/if.h>
-#include <sys/socket.h>
-#include <sys/types.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
-#include <netdb.h>
-
-const char *progname = "check_dhcp";
-
-/*#define DEBUG*/
-#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
-
-
-/**** DHCP definitions ****/
-
-#define MAX_DHCP_CHADDR_LENGTH           16
-#define MAX_DHCP_SNAME_LENGTH            64
-#define MAX_DHCP_FILE_LENGTH             128
-#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 */
-	struct dhcp_offer_struct *next;
-        }dhcp_offer;
-
-
-typedef struct requested_server_struct{
-	struct in_addr server_address;
-	struct requested_server_struct *next;
-        }requested_server;
-
-
-#define BOOTREQUEST     1
-#define BOOTREPLY       2
-
-#define DHCPDISCOVER    1
-#define DHCPOFFER       2
-#define DHCPREQUEST     3
-#define DHCPDECLINE     4
-#define DHCPACK         5
-#define DHCPNACK        6
-#define DHCPRELEASE     7
-
-#define DHCP_OPTION_MESSAGE_TYPE        53
-#define DHCP_OPTION_HOST_NAME           12
-#define DHCP_OPTION_BROADCAST_ADDRESS   28
-#define DHCP_OPTION_REQUESTED_ADDRESS   50
-#define DHCP_OPTION_LEASE_TIME          51
-#define DHCP_OPTION_RENEWAL_TIME        58
-#define DHCP_OPTION_REBINDING_TIME      59
-
-#define DHCP_INFINITE_TIME              0xFFFFFFFF
-
-#define DHCP_BROADCAST_FLAG 32768
-
-#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 */
-
-unsigned char client_hardware_address[MAX_DHCP_CHADDR_LENGTH]="";
-
-char network_interface_name[8]="eth0";
-
-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;
-
-int dhcpoffer_timeout=2;
-
-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 request_specific_address=FALSE;
-int received_requested_address=FALSE;
-struct in_addr requested_address;
-
-
-int process_arguments(int, char **);
-int call_getopt(int, char **);
-int validate_arguments(void);
-void print_usage(void);
-void print_help(void);
-
-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 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 main(int argc, char **argv){
-	int dhcp_socket;
-	int result;
-
-	if(process_arguments(argc,argv)!=OK){
-		/*usage("Invalid command arguments supplied\n");*/
-		printf("Invalid command arguments supplied\n");
-		exit(STATE_UNKNOWN);
-	        }
-
-
-	/* create socket for DHCP communications */
-	dhcp_socket=create_dhcp_socket();
-
-	/* get hardware address of client machine */
-	get_hardware_address(dhcp_socket,network_interface_name);
-
-	/* send DHCPDISCOVER packet */
-	send_dhcp_discover(dhcp_socket);
-
-	/* wait for a DHCPOFFER packet */
-	get_dhcp_offer(dhcp_socket);
-
-	/* close socket we created */
-	close_dhcp_socket(dhcp_socket);
-
-	/* determine state/plugin output to return */
-	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){
-	struct ifreq ifr;
-
-	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);
-		exit(STATE_UNKNOWN);
-	        }
-
-	memcpy(&client_hardware_address[0],&ifr.ifr_hwaddr.sa_data,6);
-
-#ifdef DEBUG
-	printf("Hardware address: %02x:%02x:%02x:",client_hardware_address[0],client_hardware_address[1],client_hardware_address[2]);
-	printf("%02x:",client_hardware_address[3]);
-	printf("%02x:%02x\n",client_hardware_address[4],client_hardware_address[5]);
-	printf("\n");
-#endif
-
-	return OK;
-        }
-
-
-/* sends a DHCPDISCOVER broadcast message in an attempt to find DHCP servers */
-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));
-
-
-	/* boot request flag (backward compatible with BOOTP servers) */
-	discover_packet.op=BOOTREQUEST;
-
-	/* hardware address type */
-	discover_packet.htype=ETHERNET_HARDWARE_ADDRESS;
-
-	/* length of our hardware address */
-	discover_packet.hlen=ETHERNET_HARDWARE_ADDRESS_LENGTH;
-
-	discover_packet.hops=0;
-
-	/* transaction id is supposed to be random */
-	srand(time(NULL));
-	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;
-
-	/* tell server it should broadcast its response */ 
-	discover_packet.flags=htons(DHCP_BROADCAST_FLAG);
-
-	/* our hardware address */
-	memcpy(discover_packet.chaddr,client_hardware_address,ETHERNET_HARDWARE_ADDRESS_LENGTH);
-
-	/* 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';
-
-	/* 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;
-
-	/* 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));
-
-
-#ifdef DEBUG
-	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));
-#endif
-
-	/* send the DHCPDISCOVER packet out */
-	send_dhcp_packet(&discover_packet,sizeof(discover_packet),sock,&sockaddr_broadcast);
-
-#ifdef DEBUG
-	printf("\n\n");
-#endif
-
-	return OK;
-        }
-
-
-
-
-/* waits for a DHCPOFFER message from one or more DHCP servers */
-int get_dhcp_offer(int sock){
-	dhcp_packet offer_packet;
-	struct sockaddr_in source;
-	int result=OK;
-	int timeout=1;
-	int responses=0;
-	int x;
-	time_t start_time;
-	time_t current_time;
-
-	time(&start_time);
-
-	/* receive as many responses as we can */
-	for(responses=0,valid_responses=0;;){
-
-		time(&current_time);
-		if((current_time-start_time)>=dhcpoffer_timeout)
-			break;
-
-#ifdef DEBUG
-		printf("\n\n");
-#endif
-
-		bzero(&source,sizeof(source));
-		bzero(&offer_packet,sizeof(offer_packet));
-
-		result=OK;
-		result=receive_dhcp_packet(&offer_packet,sizeof(offer_packet),sock,dhcpoffer_timeout,&source);
-		
-		if(result!=OK){
-#ifdef DEBUG
-			printf("Result=ERROR\n");
-#endif
-			continue;
-		        }
-		else{
-#ifdef DEBUG
-			printf("Result=OK\n");
-#endif
-			responses++;
-		        }
-
-#ifdef DEBUG
-		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));
-#endif
-
-		/* 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){
-#ifdef DEBUG
-			printf("DHCPOFFER XID (%lu) did not match DHCPDISCOVER XID (%lu) - ignoring packet\n",ntohl(offer_packet.xid),packet_xid);
-#endif
-			continue;
-		        }
-
-		/* check hardware address */
-		result=OK;
-#ifdef DEBUG
-		printf("DHCPOFFER chaddr: ");
-#endif
-		for(x=0;x<ETHERNET_HARDWARE_ADDRESS_LENGTH;x++){
-#ifdef DEBUG
-			printf("%02X",(unsigned char)offer_packet.chaddr[x]);
-#endif
-			if(offer_packet.chaddr[x]!=client_hardware_address[x]){
-				result=ERROR;
-			        }
-		        }
-#ifdef DEBUG
-		printf("\n");
-#endif
-		if(result==ERROR){
-#ifdef DEBUG
-			printf("DHCPOFFER hardware address did not match our own - ignoring packet\n");
-#endif
-			continue;
-		        }
-
-#ifdef DEBUG
-		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));
-#endif
-
-		add_dhcp_offer(source.sin_addr,&offer_packet);
-
-		valid_responses++;
-	        }
-
-#ifdef DEBUG
-	printf("Total responses seen on the wire: %d\n",responses);
-	printf("Valid responses for this machine: %d\n",valid_responses);
-#endif
-
-	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 result;
-
-	result=sendto(sock,(char *)buffer,buffer_size,0,(struct sockaddr *)dest,sizeof(*dest));
-
-#ifdef DEBUG
-	printf("send_dhcp_packet result: %d\n",result);
-#endif
-
-	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 recv_result;
-	socklen_t address_size;
-	struct sockaddr_in source_address;
-
-
-        /* 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)){
-#ifdef DEBUG
-                printf("No (more) data received\n");
-#endif
-                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);
-#ifdef DEBUG
-		printf("recv_result_1: %d\n",recv_result);
-#endif
-                recv_result=recvfrom(sock,(char *)buffer,buffer_size,0,(struct sockaddr *)&source_address,&address_size);
-#ifdef DEBUG
-		printf("recv_result_2: %d\n",recv_result);
-#endif
-
-                if(recv_result==-1){
-#ifdef DEBUG
-			printf("recvfrom() failed, ");
-			printf("errno: (%d) -> %s\n",errno,strerror(errno));
-#endif
-                        return ERROR;
-                        }
-		else{
-#ifdef DEBUG
-			printf("receive_dhcp_packet() result: %d\n",recv_result);
-			printf("receive_dhcp_packet() source: %s\n",inet_ntoa(source_address.sin_addr));
-#endif
-
-			memcpy(address,&source_address,sizeof(source_address));
-			return OK;
-		        }
-                }
-
-	return OK;
-        }
-
-
-
-/* creates a socket for DHCP communication */
-int create_dhcp_socket(void){
-        struct sockaddr_in myname;
-	struct ifreq interface;
-        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){
-		printf("Error: Could not create socket!\n");
-		exit(STATE_UNKNOWN);
-	        }
-
-#ifdef DEBUG
-	printf("DHCP socket: %d\n",sock);
-#endif
-
-        /* 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){
-		printf("Error: Could not set broadcast option on DHCP socket!\n");
-		exit(STATE_UNKNOWN);
-	        }
-
-	/* bind socket to interface */
-	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);
-	        }
-
-        /* 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;
-        }
-
-
-
-
-/* adds a requested server address to list in memory */
-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)
-		return ERROR;
-
-	new_server->server_address=server_address;
-
-	new_server->next=requested_server_list;
-	requested_server_list=new_server;
-
-	requested_servers++;
-
-#ifdef DEBUG
-	printf("Requested server address: %s\n",inet_ntoa(new_server->server_address));
-#endif
-
-	return OK;
-        }
-
-
-
-
-/* adds a DHCP OFFER to list in memory */
-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;
-
-	/* process all DHCP options present in the packet */
-	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)
-			break;
-
-		/* get option type */
-		option_type=offer_packet->options[x++];
-
-		/* get option length */
-		option_length=offer_packet->options[x++];
-
-#ifdef DEBUG
-		printf("Option: %d (0x%02X)\n",option_type,option_length);
-#endif
-
-		/* get option data */
-		if(option_type==DHCP_OPTION_LEASE_TIME)
-			dhcp_lease_time=ntohl(*((u_int32_t *)&offer_packet->options[x]));
-		if(option_type==DHCP_OPTION_RENEWAL_TIME)
-			dhcp_renewal_time=ntohl(*((u_int32_t *)&offer_packet->options[x]));
-		if(option_type==DHCP_OPTION_REBINDING_TIME)
-			dhcp_rebinding_time=ntohl(*((u_int32_t *)&offer_packet->options[x]));
-
-		/* skip option data we're ignoring */
-		else
-			for(y=0;y<option_length;y++,x++);
-	        }
-
-#ifdef DEBUG
-	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("Renewal Time: Infinite\n");
-	else
-		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);
-#endif
-
-	new_offer=(dhcp_offer *)malloc(sizeof(dhcp_offer));
-
-	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;
-
-
-#ifdef DEBUG
-	printf("Added offer from server @ %s",inet_ntoa(new_offer->server_address));
-	printf(" of IP address %s\n",inet_ntoa(new_offer->offered_address));
-#endif
-
-	/* add new offer to head of list */
-	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){
-	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;
-		free(this_offer);
-	        }
-
-	return OK;
-        }
-
-
-
-
-/* frees memory allocated to requested server list */
-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;
-		free(this_server);
-	        }
-	
-	return OK;
-        }
-
-
-/* gets state and plugin output to return */
-int get_results(void){
-	dhcp_offer *temp_offer;
-	requested_server *temp_server;
-	int result;
-	u_int32_t max_lease_time=0;
-
-	received_requested_address=FALSE;
-
-	/* checks responses from requested servers */
-	requested_responses=0;
-	if(requested_servers>0){
-
-		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){
-
-				/* 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;
-				
-				/* see if we got the address we requested */
-				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))){
-#ifdef DEBUG
-					printf("DHCP Server Match: Offerer=%s",inet_ntoa(temp_offer->server_address));
-					printf(" Requested=%s\n",inet_ntoa(temp_server->server_address));
-#endif				       
-					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){
-
-			/* 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;
-				
-			/* 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;
-
-
-	printf("DHCP %s: ",(result==STATE_OK)?"ok":"problem");
-
-	/* we didn't receive any DHCPOFFERs */
-	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);
-
-	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)
-		printf("Infinity");
-	else
-		printf("%lu sec",(unsigned long)max_lease_time);
-
-	printf(".\n");
-
-	return result;
-        }
-
-
-
-
-
-
-/* print usage help */
-void print_help(void){
-
-	/*print_revision(progname,"$Revision$");*/
-
-	printf("Copyright (c) 2001-2004 Ethan Galstad (nagios@nagios.org)\n\n");
-	printf("This plugin tests the availability of DHCP servers on a network.\n\n");
-
-	print_usage();
-
-	printf
-		("\nOptions:\n"
-		 " -s, --serverip=IPADDRESS\n"
-		 "   IP address of DHCP server that we must hear from\n"
-		 " -r, --requestedip=IPADDRESS\n"
-		 "   IP address that should be offered by at least one DHCP server\n"
-		 " -t, --timeout=INTEGER\n"
-		 "   Seconds to wait for DHCPOFFER before timeout occurs\n"
-		 " -i, --interface=STRING\n"
-		 "   Interface to to use for listening (i.e. eth0)\n"
-		 " -v, --verbose\n"
-		 "   Print extra information (command-line use only)\n"
-		 " -h, --help\n"
-		 "   Print detailed help screen\n"
-		 " -V, --version\n"
-		 "   Print version information\n\n"
-		 );
-
-	/*support();*/
-
-	return;
-        }
-
-
-/* prints usage information */
-void print_usage(void){
-
-	printf("Usage: %s [-s serverip] [-r requestedip] [-t timeout] [-i interface]\n",progname);
-	printf("       %s --help\n",progname);
-	printf("       %s --version\n",progname);
-
-	return;
-        }
-
-
-
-
-/* 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;
-	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
-
-		i++;
-
-		if(c==-1||c==EOF||c==1)
-			break;
-
-		switch(c){
-		case 'w':
-		case 'r':
-		case 't':
-		case 'i':
-			i++;
-			break;
-		default:
-			break;
-		        }
-
-		switch(c){
-
-		case 's': /* DHCP server address */
-			if(inet_aton(optarg,&ipaddress))
-				add_requested_server(ipaddress);
-			/*
-			else
-				usage("Invalid server IP address\n");
-			*/
-			break;
-
-		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");
-			*/
-			break;
-
-		case 't': /* timeout */
-
-			/*
-			if(is_intnonneg(optarg))
-			*/
-			if(atoi(optarg)>0)
-				dhcpoffer_timeout=atoi(optarg);
-			/*
-			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';
-
-			break;
-
-		case 'V': /* version */
-
-			/*print_revision(progname,"$Revision$");*/
-			exit(STATE_OK);
-
-		case 'h': /* help */
-
-			print_help();
-			exit(STATE_OK);
-
-		case '?': /* help */
-
-			/*usage("Invalid argument\n");*/
-			break;
-
-		default:
-			break;
-		        }
-	        }
-
-	return i;
-        }
-
-
-
-int validate_arguments(void){
-
-	return OK;
-        }
-