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dhcp-debug.c
#include <time.h>
#include <stdio.h>
#include <stdlib.h>
#include <locale.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/time.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <getopt.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netdb.h>
#include <netinet/in.h>
#include <net/if.h>
#include <arpa/inet.h>
// =================================================================
//
// Title:
// CHECK_DHCP.C
//
// Copyright:
// Program: DHCP plugin for Nagios
// Author: 2001-2004 Ethan Galstad (nagios@nagios.org)
// Copyright: (c) 2001-2004 Ethan Galstad (nagios@nagios.org)
// License: GPL
// Modified by: Mike Gore 25 Aug 2005
// Notes:
// Modified for standalone operation - removed usage2,usage4, etc
// Removed printf(_( style)) and replaced with printf()
// added standalone COPYRIGHT string and print_revision()
// Added ability to set MAC address of client
// Notes:
// -s serverip
// -t timeout
// -i interface
// -m mac
// -v verbose
// -v version
// -help
// Example: dhcp -i eth0
//
// ======================================================
//
// License: GPL
// 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.
//
//
// $Id: check_dhcp.c,v 1.7 2005/01/25 18:11:21 harpermann Exp $
//
// =================================================================
const char *COPYRIGHT= "\n"
"=================================================================\n"
"CHECK_DHCP.C\n"
"\n"
"Program: DHCP plugin for Nagios\n"
"Author: 2001-2004 Ethan Galstad (nagios@nagios.org)\n"
"Copyright: (c) 2001-2004 Ethan Galstad (nagios@nagios.org)\n"
"License: GPL\n"
"======================================================\n"
"Author: Mike Gore 25 Aug 2005\n"
" Modified for standalone operation - without usage2,usage4, etc\n"
" Removed printf(_( style and replaced with printf(\n"
" added standalone COPYRIGHT string and print_revision()\n"
" Added ability to set MAC address\n"
"======================================================\n"
"\n"
"License: GPL\n"
"This program is free software; you can redistribute it and/or modify\n"
"it under the terms of the GNU General Public License as published by\n"
"the Free Software Foundation; either version 2 of the License, or\n"
"(at your option) any later version.\n"
"This program is distributed in the hope that it will be useful,\n"
"but WITHOUT ANY WARRANTY; without even the implied warranty of\n"
"MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the\n"
"GNU General Public License for more details.\n"
"You should have received a copy of the GNU General Public License\n"
"along with this program; if not, write to the Free Software\n"
"Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.\n"
"\n"
"\n"
"$Id: check_dhcp.c,v 1.7 2005/01/25 18:11:21 harpermann Exp $\n"
"\n"
"=================================================================\n";
const char *progname = "check_dhcp";
const char *revision = "$Revision: 1.7 $";
const char *copyright = "2001-2004";
const char *email = "nagiosplug-devel@lists.sourceforge.net";
#if defined( __linux__ )
#include <linux/if_ether.h>
#include <features.h>
#elif defined (__bsd__)
#include <netinet/if_ether.h>
#include <sys/sysctl.h>
#include <net/if_dl.h>
#elif defined(__sun__) || defined(__solaris__) || defined(__hpux__)
#define INSAP 22
#define OUTSAP 24
#include <signal.h>
#include <ctype.h>
#include <sys/stropts.h>
#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 */
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};
#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
#define u_int32_t uint32_t
static int get_msg(int);
static int check_ctrl(int);
static int put_ctrl(int, int, int);
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 *);
#endif
#define HAVE_GETOPT_H
#define usage printf
/**** 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]="";
unsigned int my_client_mac[MAX_DHCP_CHADDR_LENGTH];
int mymac = 0;
char network_interface_name[32]="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;
int verbose=0;
struct in_addr requested_address;
void print_revision(const char *progname,const char *revision)
{
printf("Program: %s %s\n",progname,revision);
}
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;
setlocale (LC_ALL, "");
// bindtextdomain (PACKAGE, LOCALEDIR);
// textdomain (PACKAGE);
if(process_arguments(argc,argv)!=OK){
printf("Could not parse arguments");
}
/* 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){
int i;
#if defined(__linux__)
struct ifreq ifr;
strncpy((char *)&ifr.ifr_name,interface_name,sizeof(ifr.ifr_name));
// Added code to try to set local MAC address just to be through
// If this fails the test will still work since
// we do encode the MAC as part of the DHCP frame - tests show it works
if(mymac)
{
int i;
for(i=0;i<MAX_DHCP_CHADDR_LENGTH;++i)
client_hardware_address[i] = my_client_mac[i];
memcpy(&ifr.ifr_hwaddr.sa_data,&client_hardware_address[0],6);
if(ioctl(sock,SIOCSIFHWADDR,&ifr)<0){
printf("Error: Could not set hardware address of interface '%s'\n",interface_name);
// perror("Error");
// exit(STATE_UNKNOWN);
}
}
else
{
/* 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);
}
#elif defined(__bsd__)
/* 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 */
#elif defined(__sun__) || defined(__solaris__)
/* 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);
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);
exit(STATE_UNKNOWN);
}
#elif defined(__hpux__)
long stat;
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);
exit(STATE_UNKNOWN);
}
/* Kompf 2000-2003 */
#else
printf("Error: can't get MAC address for this architecture.\n");
exit(STATE_UNKNOWN);
#endif
if (verbose) {
printf("Hardware address: ");
for (i=0; i<6; ++i)
printf("%2.2x", client_hardware_address[i]);
printf( "\n");
}
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));
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",(unsigned long) 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);
if (verbose)
printf("\n\n");
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;
if (verbose)
printf("\n\n");
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){
if (verbose)
printf("Result=ERROR\n");
continue;
}
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",(unsigned long) 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",(unsigned long) ntohl(offer_packet.xid),(unsigned long) 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]);
if(offer_packet.chaddr[x]!=client_hardware_address[x])
result=ERROR;
}
if (verbose)
printf("\n");
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));
}
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);
}
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));
if (verbose)
printf("send_dhcp_packet result: %d\n",result);
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)){
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));
}
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);
}
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){
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 */
#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);
exit(STATE_UNKNOWN);
}
#else
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);
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++;
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){
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++];
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);
}
/* skip option data we're ignoring */
else
for(y=0;y<option_length;y++,x++);
}
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("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);
}
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;
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;
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))){
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){
/* 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;
}
/* 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'},
{"mac", required_argument,0,'m'},
{"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:m:",long_options,&option_index);
#else
c=getopt(argc,argv,"+?hVvt:s:r:t:i:m:");
#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 'm': /* Our MAC address */
{
int ret;
ret = sscanf(optarg,"%x:%x:%x:%x:%x:%x",
my_client_mac+0,
my_client_mac+1,
my_client_mac+2,
my_client_mac+3,
my_client_mac+4,
my_client_mac+5);
if(ret != 6) {
usage("Invalid MAC address\n");
break;
}
for(i=0;i<6;++i)
client_hardware_address[i] = my_client_mac[i];
}
mymac = 1;
break;
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 'v': /* verbose */
verbose=1;
break;
case '?': /* help */
printf("Unknown argument:%s\n", optarg);
break;
default:
break;
}
}
return i;
}
int validate_arguments(void){
return OK;
}
#if defined(__sun__) || defined(__solaris__) || defined(__hpux__)
/* Kompf 2000-2003 see ACKNOWLEDGEMENTS */
/* get a message from a stream; return type of message */
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);
}
/* verify that dl_primitive in ctl_area = 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;
}
/* put a control message on a stream */
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;
}
/* put a control + data message on a stream */
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;
}
/* open file descriptor and attach */
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);
}
/* send DL_BIND_REQ */
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;
}
/***********************************************************************
* interface:
* function mac_addr_dlpi - get the mac address of the interface with
* type dev (eg lnc, hme) and unit (0, 1 ..)
*
* parameter: addr: an array of six bytes, has to be allocated by the caller
*
* return: 0 if OK, -1 if the address could not be determined
*
*
***********************************************************************/
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;
}
}
close(fd);
return -1;
}
/* Kompf 2000-2003 */
#endif
// Usage:
// Copyright (c 2001-2004 Ethan Galstad (nagios@nagios.org;
// COPYRIGHT, copyright, email;
// This plugin tests the availability of DHCP servers on a network.;
//
// -s, --serverip=IPADDRESS
// IP address of DHCP server that we must hear from
// -r, --requestedip=IPADDRESS
// IP address that should be offered by at least one DHCP server
// -t, --timeout=INTEGER
// Seconds to wait for DHCPOFFER before timeout occurs
// -i, --interface=STRING
// Interface to to use for listening (i.e. eth0
// -m, --mac=MAC ADDRESS
// Set MAC Address
// -v, --verbose
// Print extra information (command-line use only)
// /* print usage help */
void print_help(void){
print_revision(progname,revision);
printf("Copyright (c) 2001-2004 Ethan Galstad (nagios@nagios.org)\n\n");
printf(COPYRIGHT, copyright, email);
printf("This plugin tests the availability of DHCP servers on a network.\n\n");
print_usage();
printf("\
-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\
-m, --mac=MAC ADDRESS\n\
Set MAC Address\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");
}
void print_usage(void)
{
printf("\
Usage: %s [-s serverip] [-r requestedip] [-t timeout] [-i interface]\n\
[-v]",progname);
}
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