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-rw-r--r--plugins-root/check_dhcp.c1412
1 files changed, 1412 insertions, 0 deletions
diff --git a/plugins-root/check_dhcp.c b/plugins-root/check_dhcp.c
new file mode 100644
index 0000000..6b07df5
--- /dev/null
+++ b/plugins-root/check_dhcp.c
@@ -0,0 +1,1412 @@
+/*****************************************************************************
+ *
+ * Monitoring check_dhcp plugin
+ *
+ * License: GPL
+ * Copyright (c) 2001-2004 Ethan Galstad (nagios@nagios.org)
+ * Copyright (c) 2001-2007 Monitoring Plugins Development Team
+ *
+ * Description:
+ *
+ * This file contains the check_dhcp plugin
+ *
+ * This plugin tests the availability of DHCP servers on a network.
+ *
+ * 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.
+ *
+ *
+ * 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 3 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, see <http://www.gnu.org/licenses/>.
+ *
+ *
+ *****************************************************************************/
+
+const char *progname = "check_dhcp";
+const char *copyright = "2001-2023";
+const char *email = "devel@monitoring-plugins.org";
+
+#include "common.h"
+#include "netutils.h"
+#include "utils.h"
+
+#include <ctype.h>
+#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 <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>
+
+#if HAVE_SYS_SOCKIO_H
+#include <sys/sockio.h>
+#endif // HAVE_SYS_SOCKIO_H
+
+#if defined( __linux__ )
+
+#include <linux/if_ether.h>
+#include <features.h>
+
+#elif defined (__bsd__)
+
+#include <netinet/if_ether.h>
+#include <sys/param.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
+
+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 // __sun__ || __solaris__ || __hpux
+
+
+
+/**** Common definitions ****/
+
+#define OK 0
+#define ERROR -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{
+ uint8_t op; /* packet type */
+ uint8_t htype; /* type of hardware address for this machine (Ethernet, etc) */
+ uint8_t hlen; /* length of hardware address (of this machine) */
+ uint8_t hops; /* hops */
+ uint32_t xid; /* random transaction id number - chosen by this machine */
+ uint16_t secs; /* seconds used in timing */
+ uint16_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 next 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 */
+ uint32_t lease_time; /* lease time in seconds */
+ uint32_t renewal_time; /* renewal time in seconds */
+ uint32_t rebinding_time; /* rebinding time in seconds */
+ bool desired; /* is this offer desired (necessary in exclusive mode) */
+ struct dhcp_offer_struct *next;
+}dhcp_offer;
+
+
+typedef struct requested_server_struct{
+ struct in_addr server_address;
+ bool answered;
+ 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_SERVER_IDENTIFIER 54
+#define DHCP_OPTION_RENEWAL_TIME 58
+#define DHCP_OPTION_REBINDING_TIME 59
+#define DHCP_OPTION_END 255
+
+#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 */
+
+bool unicast = false; /* unicast mode: mimic a DHCP relay */
+bool exclusive = false; /* exclusive mode aka "rogue DHCP server detection" */
+struct in_addr my_ip; /* our address (required for relay) */
+struct in_addr dhcp_ip; /* server to query (if in unicast mode) */
+unsigned char client_hardware_address[MAX_DHCP_CHADDR_LENGTH]="";
+unsigned char *user_specified_mac=NULL;
+
+char network_interface_name[IFNAMSIZ]="eth0";
+
+uint32_t packet_xid=0;
+
+uint32_t dhcp_lease_time=0;
+uint32_t dhcp_renewal_time=0;
+uint32_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;
+
+bool request_specific_address=false;
+bool received_requested_address=false;
+int verbose=0;
+struct in_addr requested_address;
+
+
+int process_arguments(int, char **);
+int call_getopt(int, char **);
+int validate_arguments(int);
+void print_usage(void);
+void print_help(void);
+
+void resolve_host(const char *in,struct in_addr *out);
+unsigned char *mac_aton(const char *);
+void print_hardware_address(const unsigned char *);
+int get_hardware_address(int,char *);
+int get_ip_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 = STATE_UNKNOWN;
+
+ setlocale (LC_ALL, "");
+ bindtextdomain (PACKAGE, LOCALEDIR);
+ textdomain (PACKAGE);
+
+ /* Parse extra opts if any */
+ argv=np_extra_opts(&argc, argv, progname);
+
+ if(process_arguments(argc,argv)!=OK){
+ usage4 (_("Could not parse arguments"));
+ }
+
+ /* create socket for DHCP communications */
+ dhcp_socket=create_dhcp_socket();
+
+ /* get hardware address of client machine */
+ if(user_specified_mac!=NULL)
+ memcpy(client_hardware_address,user_specified_mac,6);
+ else
+ get_hardware_address(dhcp_socket,network_interface_name);
+
+ if(unicast) /* get IP address of client machine */
+ get_ip_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){
+
+#if defined(__linux__)
+ struct ifreq ifr;
+
+ strncpy((char *)&ifr.ifr_name,interface_name,sizeof(ifr.ifr_name)-1);
+ ifr.ifr_name[sizeof(ifr.ifr_name)-1]='\0';
+
+ /* 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 */
+
+ size_t len;
+ int mib[6];
+ 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;
+
+ /* get last number from interfacename, eg lnc0, e1000g0*/
+ int i;
+ p = interface_name + strlen(interface_name) -1;
+ for(i = strlen(interface_name) -1; i > 0; p--) {
+ if(isalpha(*p))
+ break;
+ }
+ p++;
+ if( p != interface_name ){
+ unit = atoi(p) ;
+ 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. Use the --mac option.\n"));
+ exit(STATE_UNKNOWN);
+#endif
+
+ if(verbose)
+ print_hardware_address(client_hardware_address);
+
+ return OK;
+}
+
+/* determines IP address of the client interface */
+int get_ip_address(int sock,char *interface_name){
+#if defined(SIOCGIFADDR)
+ struct ifreq ifr;
+
+ strncpy((char *)&ifr.ifr_name,interface_name,sizeof(ifr.ifr_name)-1);
+ ifr.ifr_name[sizeof(ifr.ifr_name)-1]='\0';
+
+ if(ioctl(sock,SIOCGIFADDR,&ifr)<0){
+ printf(_("Error: Cannot determine IP address of interface %s\n"),
+ interface_name);
+ exit(STATE_UNKNOWN);
+ }
+
+ my_ip=((struct sockaddr_in *)&ifr.ifr_addr)->sin_addr;
+
+#else
+ printf(_("Error: Cannot get interface IP address on this platform.\n"));
+ exit(STATE_UNKNOWN);
+#endif
+
+ if(verbose)
+ printf(_("Pretending to be relay client %s\n"),inet_ntoa(my_ip));
+
+ 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;
+ unsigned short opts;
+
+
+ /* 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;
+
+ /*
+ * transaction ID is supposed to be random.
+ */
+ srand(time(NULL)^getpid());
+ packet_xid=random();
+ discover_packet.xid=htonl(packet_xid);
+
+ /*discover_packet.secs=htons(65535);*/
+ discover_packet.secs=0xFF;
+
+ /*
+ * server needs to know if it should broadcast or unicast its response:
+ * 0x8000L == 32768 == 1 << 15 == broadcast, 0 == unicast
+ */
+ discover_packet.flags = unicast ? 0 : 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';
+
+ opts = 4;
+ /* DHCP message type is embedded in options field */
+ discover_packet.options[opts++]=DHCP_OPTION_MESSAGE_TYPE; /* DHCP message type option identifier */
+ discover_packet.options[opts++]='\x01'; /* DHCP message option length in bytes */
+ discover_packet.options[opts++]=DHCPDISCOVER;
+
+ /* the IP address we're requesting */
+ if(request_specific_address){
+ discover_packet.options[opts++]=DHCP_OPTION_REQUESTED_ADDRESS;
+ discover_packet.options[opts++]='\x04';
+ memcpy(&discover_packet.options[opts],&requested_address,sizeof(requested_address));
+ opts += sizeof(requested_address);
+ }
+ discover_packet.options[opts++]=DHCP_OPTION_END;
+
+ /* unicast fields */
+ if(unicast)
+ discover_packet.giaddr.s_addr = my_ip.s_addr;
+
+ /* see RFC 1542, 4.1.1 */
+ discover_packet.hops = unicast ? 1 : 0;
+
+ /* 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 ? dhcp_ip.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: %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);
+
+ 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;
+ struct sockaddr_in via;
+ int result=OK;
+ 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(&via,sizeof(via));
+ 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++;
+ }
+
+ /* The "source" is either a server or a relay. */
+ /* Save a copy of "source" into "via" even if it's via itself */
+ memcpy(&via,&source,sizeof(source)) ;
+
+ if(verbose){
+ printf(_("DHCPOFFER from IP address %s"),inet_ntoa(source.sin_addr));
+ printf(_(" via %s\n"),inet_ntoa(via.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 (%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]);
+
+ 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){
+ 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;
+ 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(_("No (more) data received (nfound: %d)\n"), nfound);
+ return ERROR;
+ }
+
+ else{
+ bzero(&source_address,sizeof(source_address));
+ address_size=sizeof(source_address);
+ recv_result=recvfrom(sock,(char *)buffer,buffer_size,0,(struct sockaddr *)&source_address,&address_size);
+ if(verbose)
+ printf("recv_result: %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;
+ /* listen to DHCP server port if we're in unicast mode */
+ myname.sin_port = htons(unicast ? DHCP_SERVER_PORT : DHCP_CLIENT_PORT);
+ myname.sin_addr.s_addr = unicast ? my_ip.s_addr : INADDR_ANY;
+ 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(!unicast && 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-1);
+ interface.ifr_ifrn.ifrn_name[IFNAMSIZ-1]='\0';
+ 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-1);
+ interface.ifr_name[IFNAMSIZ-1]='\0';
+#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->answered=false;
+
+ 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;
+ unsigned option_type;
+ unsigned option_length;
+ struct in_addr serv_ident = {0};
+
+ if(offer_packet==NULL)
+ return ERROR;
+
+ /* process all DHCP options present in the packet */
+ for(x=4;x<MAX_DHCP_OPTIONS_LENGTH-1;){
+
+ if((int)offer_packet->options[x]==-1)
+ 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 */
+ switch(option_type){
+ case DHCP_OPTION_LEASE_TIME:
+ memcpy(&dhcp_lease_time, &offer_packet->options[x],sizeof(dhcp_lease_time));
+ dhcp_lease_time = ntohl(dhcp_lease_time);
+ break;
+ case DHCP_OPTION_RENEWAL_TIME:
+ memcpy(&dhcp_renewal_time, &offer_packet->options[x],sizeof(dhcp_renewal_time));
+ dhcp_renewal_time = ntohl(dhcp_renewal_time);
+ break;
+ case DHCP_OPTION_REBINDING_TIME:
+ memcpy(&dhcp_rebinding_time, &offer_packet->options[x],sizeof(dhcp_rebinding_time));
+ dhcp_rebinding_time = ntohl(dhcp_rebinding_time);
+ break;
+ case DHCP_OPTION_SERVER_IDENTIFIER:
+ memcpy(&serv_ident.s_addr, &offer_packet->options[x],sizeof(serv_ident.s_addr));
+ break;
+ }
+
+ /* skip option data we're ignoring */
+ if(option_type==0) /* "pad" option, see RFC 2132 (3.1) */
+ x+=1;
+ else
+ x+=option_length;
+ }
+
+ 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;
+
+ /*
+ * RFC 2131 (2.) says: "DHCP clarifies the interpretation of the
+ * 'siaddr' field as the address of the server to use in the next step
+ * of the client's bootstrap process. A DHCP server may return its own
+ * address in the 'siaddr' field, if the server is prepared to supply
+ * the next bootstrap service (e.g., delivery of an operating system
+ * executable image). A DHCP server always returns its own address in
+ * the 'server identifier' option." 'serv_ident' is the 'server
+ * identifier' option, 'source' is the IP address we received the
+ * DHCPOFFER from. If 'serv_ident' isn't available for some reason, we
+ * use 'source'.
+ */
+ new_offer->server_address=serv_ident.s_addr?serv_ident: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->desired=false; /* exclusive mode: we'll check that in get_results */
+
+
+ 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, *undesired_offer=NULL;
+ requested_server *temp_server;
+ int result;
+ uint32_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"),inet_ntoa(temp_server->server_address));
+ if(temp_server->answered)
+ printf(_(" (duplicate)"));
+ printf(_("\n"));
+ }
+ if(!temp_server->answered){
+ requested_responses++;
+ temp_server->answered=true;
+ temp_offer->desired=true;
+ }
+ }
+ }
+ }
+
+ /* exclusive mode: check for undesired offers */
+ for(temp_offer=dhcp_offer_list;temp_offer!=NULL;temp_offer=temp_offer->next) {
+ if (!temp_offer->desired) {
+ undesired_offer=temp_offer; /* Checks only for the first undesired offer */
+ break; /* no further checks needed */
+ }
+ }
+ }
+
+ /* 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 && !received_requested_address)
+ result=STATE_WARNING;
+
+ if(exclusive && undesired_offer)
+ result=STATE_CRITICAL;
+
+ if(result==0) /* garrett honeycutt 2005 */
+ printf("OK: ");
+ else if(result==1)
+ printf("WARNING: ");
+ else if(result==2)
+ printf("CRITICAL: ");
+ else if(result==3)
+ printf("UNKNOWN: ");
+
+ /* 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(exclusive && undesired_offer){
+ printf(_(", Rogue DHCP Server detected! Server %s"),inet_ntoa(undesired_offer->server_address));
+ printf(_(" offered %s \n"),inet_ntoa(undesired_offer->offered_address));
+ return result;
+ }
+
+ 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)
+ printf(_(", requested address (%s) was %soffered"),inet_ntoa(requested_address),(received_requested_address)?"":_("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){
+ if(argc<1)
+ return ERROR;
+
+ call_getopt(argc,argv);
+ return validate_arguments(argc);
+}
+
+
+
+int call_getopt(int argc, char **argv){
+ extern int optind;
+ 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'},
+ {"unicast", no_argument, 0,'u'},
+ {"exclusive", no_argument, 0,'x'},
+ {"verbose", no_argument, 0,'v'},
+ {"version", no_argument, 0,'V'},
+ {"help", no_argument, 0,'h'},
+ {0,0,0,0}
+ };
+
+ int c=0;
+ while(true){
+ c=getopt_long(argc,argv,"+hVvxt:s:r:t:i:m:u",long_options,&option_index);
+
+ if(c==-1||c==EOF||c==1)
+ break;
+
+ switch(c){
+
+ case 's': /* DHCP server address */
+ resolve_host(optarg,&dhcp_ip);
+ add_requested_server(dhcp_ip);
+ break;
+
+ case 'r': /* address we are requested from DHCP servers */
+ resolve_host(optarg,&requested_address);
+ request_specific_address=true;
+ 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 'm': /* MAC address */
+
+ if((user_specified_mac=mac_aton(optarg)) == NULL)
+ usage("Cannot parse MAC address.\n");
+ if(verbose)
+ print_hardware_address(user_specified_mac);
+
+ 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 'u': /* unicast testing */
+ unicast=true;
+ break;
+ case 'x': /* exclusive testing aka "rogue DHCP server detection" */
+ exclusive=true;
+ break;
+
+ case 'V': /* version */
+ print_revision(progname, NP_VERSION);
+ exit(STATE_UNKNOWN);
+
+ case 'h': /* help */
+ print_help();
+ exit(STATE_UNKNOWN);
+
+ case 'v': /* verbose */
+ verbose=1;
+ break;
+ case '?': /* help */
+ usage5 ();
+ break;
+
+ default:
+ break;
+ }
+ }
+ return optind;
+}
+
+
+int validate_arguments(int argc){
+
+ if(argc - optind > 0)
+ usage(_("Got unexpected non-option argument"));
+
+ 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
+
+
+/* resolve host name or die (TODO: move this to netutils.c!) */
+void resolve_host(const char *in,struct in_addr *out){
+ struct addrinfo hints, *ai;
+
+ memset(&hints,0,sizeof(hints));
+ hints.ai_family=PF_INET;
+ if (getaddrinfo(in,NULL,&hints,&ai) != 0)
+ usage_va(_("Invalid hostname/address - %s"),optarg);
+
+ memcpy(out,&((struct sockaddr_in *)ai->ai_addr)->sin_addr,sizeof(*out));
+ freeaddrinfo(ai);
+}
+
+
+/* parse MAC address string, return 6 bytes (unterminated) or NULL */
+unsigned char *mac_aton(const char *string){
+ static unsigned char result[6];
+ char tmp[3];
+ unsigned i, j;
+
+ for(i=0, j=0; string[i] != '\0' && j < sizeof(result); i++){
+ /* ignore ':' and any other non-hex character */
+ if(!isxdigit(string[i]) || !isxdigit(string[i+1]))
+ continue;
+ tmp[0]=string[i];
+ tmp[1]=string[i+1];
+ tmp[2]='\0';
+ result[j]=strtol(tmp,(char **)NULL,16);
+ i++;
+ j++;
+ }
+
+ return (j==6) ? result : NULL;
+}
+
+
+void print_hardware_address(const unsigned char *address){
+ int i;
+
+ printf(_("Hardware address: "));
+ for (i=0; i<5; i++)
+ printf("%2.2x:", address[i]);
+ printf("%2.2x", address[i]);
+ putchar('\n');
+}
+
+
+/* print usage help */
+void print_help(void){
+
+ print_revision(progname, NP_VERSION);
+
+ printf("Copyright (c) 2001-2004 Ethan Galstad (nagios@nagios.org)\n");
+ printf (COPYRIGHT, copyright, email);
+
+ printf("%s\n", _("This plugin tests the availability of DHCP servers on a network."));
+
+ printf ("\n\n");
+
+ print_usage();
+
+ printf (UT_HELP_VRSN);
+ printf (UT_EXTRA_OPTS);
+
+ printf (UT_VERBOSE);
+
+ printf (" %s\n", "-s, --serverip=IPADDRESS");
+ printf (" %s\n", _("IP address of DHCP server that we must hear from"));
+ printf (" %s\n", "-r, --requestedip=IPADDRESS");
+ printf (" %s\n", _("IP address that should be offered by at least one DHCP server"));
+ printf (" %s\n", "-t, --timeout=INTEGER");
+ printf (" %s\n", _("Seconds to wait for DHCPOFFER before timeout occurs"));
+ printf (" %s\n", "-i, --interface=STRING");
+ printf (" %s\n", _("Interface to to use for listening (i.e. eth0)"));
+ printf (" %s\n", "-m, --mac=STRING");
+ printf (" %s\n", _("MAC address to use in the DHCP request"));
+ printf (" %s\n", "-u, --unicast");
+ printf (" %s\n", _("Unicast testing: mimic a DHCP relay, requires -s"));
+ printf (" %s\n", "-x, --exclusive");
+ printf (" %s\n", _("Only requested DHCP server may response (rogue DHCP server detection), requires -s"));
+
+ printf (UT_SUPPORT);
+ return;
+}
+
+
+void
+print_usage(void){
+
+ printf ("%s\n", _("Usage:"));
+ printf (" %s [-v] [-u] [-x] [-s serverip] [-r requestedip] [-t timeout]\n",progname);
+ printf (" [-i interface] [-m mac]\n");
+
+ return;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-22 20:29:20 +0000