plugins-root/check_dhcp.c

   1 /******************************************************************************
   2 *
   3 * Nagios check_dhcp plugin
   4 *
   5 * License: GPL
   6 * Copyright (c) 2001-2004 Ethan Galstad (nagios@nagios.org)
   7 * Copyright (c) 2001-2006 Nagios Plugin Development Team
   8 *
   9 * Last Modified: $Date$
  10 *
  11 * Description:
  12 *
  13 * This file contains the check_dhcp plugin
  14 *
  15 *  This plugin tests the availability of DHCP servers on a network.
  16 *
  17 *
  18 * License Information:
  19 *
  20 * This program is free software; you can redistribute it and/or modify
  21 * it under the terms of the GNU General Public License as published by
  22 * the Free Software Foundation; either version 2 of the License, or
  23 * (at your option) any later version.
  24 *
  25 * This program is distributed in the hope that it will be useful,
  26 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  27 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  28 * GNU General Public License for more details.
  29 *
  30 * You should have received a copy of the GNU General Public License
  31 * along with this program; if not, write to the Free Software
  32 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  33 *
  34 * $Id$
  35 *
  36 *****************************************************************************/
  37
  38 const char *progname = "check_dhcp";
  39 const char *revision = "$Revision$";
  40 const char *copyright = "2001-2006";
  41 const char *email = "nagiosplug-devel@lists.sourceforge.net";
  42
  43 #include "common.h"
  44 #include "netutils.h"
  45 #include "utils.h"
  46
  47 #include <stdio.h>
  48 #include <stdlib.h>
  49 #include <string.h>
  50 #include <errno.h>
  51 #include <unistd.h>
  52 #include <sys/time.h>
  53 #include <sys/ioctl.h>
  54 #include <fcntl.h>
  55 #include <getopt.h>
  56 #include <sys/socket.h>
  57 #include <sys/types.h>
  58 #include <netdb.h>
  59 #include <netinet/in.h>
  60 #include <net/if.h>
  61 #include <arpa/inet.h>
  62
  63 #if defined( __linux__ )
  64
  65 #include <linux/if_ether.h>
  66 #include <features.h>
  67
  68 #elif defined (__bsd__)
  69
  70 #include <netinet/if_ether.h>
  71 #include <sys/param.h>
  72 #include <sys/sysctl.h>
  73 #include <net/if_dl.h>
  74
  75 #elif defined(__sun__) || defined(__solaris__) || defined(__hpux__)
  76
  77 #define INSAP 22
  78 #define OUTSAP 24
  79
  80 #include <signal.h>
  81 #include <ctype.h>
  82 #include <sys/stropts.h>
  83 #include <sys/poll.h>
  84 #include <sys/dlpi.h>
  85
  86 #define bcopy(source, destination, length) memcpy(destination, source, length)
  87
  88 #define AREA_SZ 5000            /* buffer length in bytes */
  89 static u_long ctl_area[AREA_SZ];
  90 static u_long dat_area[AREA_SZ];
  91 static struct strbuf ctl = {AREA_SZ, 0, (char *)ctl_area};
  92 static struct strbuf dat = {AREA_SZ, 0, (char *)dat_area};
  93
  94 #define GOT_CTRL 1
  95 #define GOT_DATA 2
  96 #define GOT_BOTH 3
  97 #define GOT_INTR 4
  98 #define GOT_ERR 128
  99
 100 #define u_int8_t         uint8_t
 101 #define u_int16_t       uint16_t
 102 #define u_int32_t       uint32_t
 103
 104 static int get_msg(int);
 105 static int check_ctrl(int);
 106 static int put_ctrl(int, int, int);
 107 static int put_both(int, int, int, int);
 108 static int dl_open(const char *, int, int *);
 109 static int dl_bind(int, int, u_char *);
 110 long mac_addr_dlpi( const char *, int, u_char *);
 111
 112 #endif
 113
 114
 115
 116 /**** Common definitions ****/
 117
 118 #define OK                0
 119 #define ERROR             -1
 120
 121 #define FALSE             0
 122 #define TRUE              1
 123
 124
 125 /**** DHCP definitions ****/
 126
 127 #define MAX_DHCP_CHADDR_LENGTH           16
 128 #define MAX_DHCP_SNAME_LENGTH            64
 129 #define MAX_DHCP_FILE_LENGTH             128
 130 #define MAX_DHCP_OPTIONS_LENGTH          312
 131
 132
 133 typedef struct dhcp_packet_struct{
 134         u_int8_t  op;                   /* packet type */
 135         u_int8_t  htype;                /* type of hardware address for this machine (Ethernet, etc) */
 136         u_int8_t  hlen;                 /* length of hardware address (of this machine) */
 137         u_int8_t  hops;                 /* hops */
 138         u_int32_t xid;                  /* random transaction id number - chosen by this machine */
 139         u_int16_t secs;                 /* seconds used in timing */
 140         u_int16_t flags;                /* flags */
 141         struct in_addr ciaddr;          /* IP address of this machine (if we already have one) */
 142         struct in_addr yiaddr;          /* IP address of this machine (offered by the DHCP server) */
 143         struct in_addr siaddr;          /* IP address of DHCP server */
 144         struct in_addr giaddr;          /* IP address of DHCP relay */
 145         unsigned char chaddr [MAX_DHCP_CHADDR_LENGTH];      /* hardware address of this machine */
 146         char sname [MAX_DHCP_SNAME_LENGTH];    /* name of DHCP server */
 147         char file [MAX_DHCP_FILE_LENGTH];      /* boot file name (used for diskless booting?) */
 148         char options[MAX_DHCP_OPTIONS_LENGTH];  /* options */
 149         }dhcp_packet;
 150
 151
 152 typedef struct dhcp_offer_struct{
 153         struct in_addr server_address;   /* address of DHCP server that sent this offer */
 154         struct in_addr offered_address;  /* the IP address that was offered to us */
 155         u_int32_t lease_time;            /* lease time in seconds */
 156         u_int32_t renewal_time;          /* renewal time in seconds */
 157         u_int32_t rebinding_time;        /* rebinding time in seconds */
 158         struct dhcp_offer_struct *next;
 159         }dhcp_offer;
 160
 161
 162 typedef struct requested_server_struct{
 163         struct in_addr server_address;
 164         int answered;
 165         struct requested_server_struct *next;
 166         }requested_server;
 167
 168
 169 #define BOOTREQUEST     1
 170 #define BOOTREPLY       2
 171
 172 #define DHCPDISCOVER    1
 173 #define DHCPOFFER       2
 174 #define DHCPREQUEST     3
 175 #define DHCPDECLINE     4
 176 #define DHCPACK         5
 177 #define DHCPNACK        6
 178 #define DHCPRELEASE     7
 179
 180 #define DHCP_OPTION_MESSAGE_TYPE        53
 181 #define DHCP_OPTION_HOST_NAME           12
 182 #define DHCP_OPTION_BROADCAST_ADDRESS   28
 183 #define DHCP_OPTION_REQUESTED_ADDRESS   50
 184 #define DHCP_OPTION_LEASE_TIME          51
 185 #define DHCP_OPTION_SERVER_IDENTIFIER   54
 186 #define DHCP_OPTION_RENEWAL_TIME        58
 187 #define DHCP_OPTION_REBINDING_TIME      59
 188 #define DHCP_OPTION_END                 255
 189
 190 #define DHCP_INFINITE_TIME              0xFFFFFFFF
 191
 192 #define DHCP_BROADCAST_FLAG 32768
 193
 194 #define DHCP_SERVER_PORT   67
 195 #define DHCP_CLIENT_PORT   68
 196
 197 #define ETHERNET_HARDWARE_ADDRESS            1     /* used in htype field of dhcp packet */
 198 #define ETHERNET_HARDWARE_ADDRESS_LENGTH     6     /* length of Ethernet hardware addresses */
 199
 200 unsigned char client_hardware_address[MAX_DHCP_CHADDR_LENGTH]="";
 201
 202 char network_interface_name[IFNAMSIZ]="eth0";
 203
 204 u_int32_t packet_xid=0;
 205
 206 u_int32_t dhcp_lease_time=0;
 207 u_int32_t dhcp_renewal_time=0;
 208 u_int32_t dhcp_rebinding_time=0;
 209
 210 int dhcpoffer_timeout=2;
 211
 212 dhcp_offer *dhcp_offer_list=NULL;
 213 requested_server *requested_server_list=NULL;
 214
 215 int valid_responses=0;     /* number of valid DHCPOFFERs we received */
 216 int requested_servers=0;
 217 int requested_responses=0;
 218
 219 int request_specific_address=FALSE;
 220 int received_requested_address=FALSE;
 221 int verbose=0;
 222 struct in_addr requested_address;
 223
 224
 225 int process_arguments(int, char **);
 226 int call_getopt(int, char **);
 227 int validate_arguments(void);
 228 void print_usage(void);
 229 void print_help(void);
 230
 231 int get_hardware_address(int,char *);
 232
 233 int send_dhcp_discover(int);
 234 int get_dhcp_offer(int);
 235
 236 int get_results(void);
 237
 238 int add_dhcp_offer(struct in_addr,dhcp_packet *);
 239 int free_dhcp_offer_list(void);
 240 int free_requested_server_list(void);
 241
 242 int create_dhcp_socket(void);
 243 int close_dhcp_socket(int);
 244 int send_dhcp_packet(void *,int,int,struct sockaddr_in *);
 245 int receive_dhcp_packet(void *,int,int,int,struct sockaddr_in *);
 246
 247
 248
 249 int main(int argc, char **argv){
 250         int dhcp_socket;
 251         int result = STATE_UNKNOWN;
 252
 253         /* this plugin almost certainly needs root permissions. */
 254         np_warn_if_not_root();
 255
 256         setlocale (LC_ALL, "");
 257         bindtextdomain (PACKAGE, LOCALEDIR);
 258         textdomain (PACKAGE);
 259
 260         if(process_arguments(argc,argv)!=OK){
 261                 usage4 (_("Could not parse arguments"));
 262                 }
 263
 264         /* create socket for DHCP communications */
 265         dhcp_socket=create_dhcp_socket();
 266
 267         /* get hardware address of client machine */
 268         get_hardware_address(dhcp_socket,network_interface_name);
 269
 270         /* send DHCPDISCOVER packet */
 271         send_dhcp_discover(dhcp_socket);
 272
 273         /* wait for a DHCPOFFER packet */
 274         get_dhcp_offer(dhcp_socket);
 275
 276         /* close socket we created */
 277         close_dhcp_socket(dhcp_socket);
 278
 279         /* determine state/plugin output to return */
 280         result=get_results();
 281
 282         /* free allocated memory */
 283         free_dhcp_offer_list();
 284         free_requested_server_list();
 285
 286         return result;
 287         }
 288
 289
 290
 291 /* determines hardware address on client machine */
 292 int get_hardware_address(int sock,char *interface_name){
 293
 294         int i;
 295
 296 #if defined(__linux__)
 297         struct ifreq ifr;
 298
 299         strncpy((char *)&ifr.ifr_name,interface_name,sizeof(ifr.ifr_name));
 300
 301         /* try and grab hardware address of requested interface */
 302         if(ioctl(sock,SIOCGIFHWADDR,&ifr)<0){
 303                 printf(_("Error: Could not get hardware address of interface '%s'\n"),interface_name);
 304                 exit(STATE_UNKNOWN);
 305                 }
 306
 307         memcpy(&client_hardware_address[0],&ifr.ifr_hwaddr.sa_data,6);
 308
 309 #elif defined(__bsd__)
 310                                                 /* King 2004    see ACKNOWLEDGEMENTS */
 311
 312         int                     mib[6], len;
 313         char                    *buf;
 314         unsigned char           *ptr;
 315         struct if_msghdr        *ifm;
 316         struct sockaddr_dl      *sdl;
 317
 318         mib[0] = CTL_NET;
 319         mib[1] = AF_ROUTE;
 320         mib[2] = 0;
 321         mib[3] = AF_LINK;
 322         mib[4] = NET_RT_IFLIST;
 323
 324         if((mib[5] = if_nametoindex(interface_name)) == 0){
 325                 printf(_("Error: if_nametoindex error - %s.\n"), strerror(errno));
 326                 exit(STATE_UNKNOWN);
 327                 }
 328
 329         if(sysctl(mib, 6, NULL, &len, NULL, 0) < 0){
 330                 printf(_("Error: Couldn't get hardware address from %s. sysctl 1 error - %s.\n"), interface_name, strerror(errno));
 331                 exit(STATE_UNKNOWN);
 332                 }
 333
 334         if((buf = malloc(len)) == NULL){
 335                 printf(_("Error: Couldn't get hardware address from interface %s. malloc error - %s.\n"), interface_name, strerror(errno));
 336                 exit(4);
 337                 }
 338
 339         if(sysctl(mib, 6, buf, &len, NULL, 0) < 0){
 340                 printf(_("Error: Couldn't get hardware address from %s. sysctl 2 error - %s.\n"), interface_name, strerror(errno));
 341                 exit(STATE_UNKNOWN);
 342                 }
 343
 344         ifm = (struct if_msghdr *)buf;
 345         sdl = (struct sockaddr_dl *)(ifm + 1);
 346         ptr = (unsigned char *)LLADDR(sdl);
 347         memcpy(&client_hardware_address[0], ptr, 6) ;
 348                                                 /* King 2004 */
 349
 350 #elif defined(__sun__) || defined(__solaris__)
 351
 352                                                 /* Kompf 2000-2003      see ACKNOWLEDGEMENTS */
 353         long stat;
 354         char dev[20] = "/dev/";
 355         char *p;
 356         int unit;
 357
 358         for(p = interface_name; *p && isalpha(*p); p++)
 359                 /* no-op */ ;
 360         if( p != '\0' ){
 361                 unit = atoi(p) ;
 362                 *p = '\0' ;
 363                 strncat(dev, interface_name, 6) ;
 364                 }
 365         else{
 366                 printf(_("Error: can't find unit number in interface_name (%s) - expecting TypeNumber eg lnc0.\n"), interface_name);
 367                 exit(STATE_UNKNOWN);
 368                 }
 369         stat = mac_addr_dlpi(dev, unit, client_hardware_address);
 370         if(stat != 0){
 371                 printf(_("Error: can't read MAC address from DLPI streams interface for device %s unit %d.\n"), dev, unit);
 372                 exit(STATE_UNKNOWN);
 373                 }
 374
 375 #elif defined(__hpux__)
 376
 377         long stat;
 378         char dev[20] = "/dev/dlpi" ;
 379         int unit = 0;
 380
 381         stat = mac_addr_dlpi(dev, unit, client_hardware_address);
 382         if(stat != 0){
 383                 printf(_("Error: can't read MAC address from DLPI streams interface for device %s unit %d.\n"), dev, unit);
 384                 exit(STATE_UNKNOWN);
 385                 }
 386                                                 /* Kompf 2000-2003 */
 387
 388 #else
 389         printf(_("Error: can't get MAC address for this architecture.\n"));
 390         exit(STATE_UNKNOWN);
 391 #endif
 392
 393         if(verbose){
 394                 printf(_("Hardware address: "));
 395                 for (i=0; i<6; ++i)
 396                         printf("%2.2x", client_hardware_address[i]);
 397                 printf( "\n");
 398                 }
 399
 400         return OK;
 401         }
 402
 403
 404 /* sends a DHCPDISCOVER broadcast message in an attempt to find DHCP servers */
 405 int send_dhcp_discover(int sock){
 406         dhcp_packet discover_packet;
 407         struct sockaddr_in sockaddr_broadcast;
 408     unsigned short opts;
 409
 410
 411         /* clear the packet data structure */
 412         bzero(&discover_packet,sizeof(discover_packet));
 413
 414
 415         /* boot request flag (backward compatible with BOOTP servers) */
 416         discover_packet.op=BOOTREQUEST;
 417
 418         /* hardware address type */
 419         discover_packet.htype=ETHERNET_HARDWARE_ADDRESS;
 420
 421         /* length of our hardware address */
 422         discover_packet.hlen=ETHERNET_HARDWARE_ADDRESS_LENGTH;
 423
 424         discover_packet.hops=0;
 425
 426         /* transaction id is supposed to be random */
 427         srand(time(NULL));
 428         packet_xid=random();
 429         discover_packet.xid=htonl(packet_xid);
 430
 431         /**** WHAT THE HECK IS UP WITH THIS?!?  IF I DON'T MAKE THIS CALL, ONLY ONE SERVER RESPONSE IS PROCESSED!!!! ****/
 432         /* downright bizzarre... */
 433         ntohl(discover_packet.xid);
 434
 435         /*discover_packet.secs=htons(65535);*/
 436         discover_packet.secs=0xFF;
 437
 438         /* tell server it should broadcast its response */
 439         discover_packet.flags=htons(DHCP_BROADCAST_FLAG);
 440
 441         /* our hardware address */
 442         memcpy(discover_packet.chaddr,client_hardware_address,ETHERNET_HARDWARE_ADDRESS_LENGTH);
 443
 444         /* first four bytes of options field is magic cookie (as per RFC 2132) */
 445         discover_packet.options[0]='\x63';
 446         discover_packet.options[1]='\x82';
 447         discover_packet.options[2]='\x53';
 448         discover_packet.options[3]='\x63';
 449
 450     opts = 4;
 451         /* DHCP message type is embedded in options field */
 452         discover_packet.options[opts++]=DHCP_OPTION_MESSAGE_TYPE;    /* DHCP message type option identifier */
 453         discover_packet.options[opts++]='\x01';               /* DHCP message option length in bytes */
 454         discover_packet.options[opts++]=DHCPDISCOVER;
 455
 456         /* the IP address we're requesting */
 457         if(request_specific_address==TRUE){
 458                 discover_packet.options[opts++]=DHCP_OPTION_REQUESTED_ADDRESS;
 459                 discover_packet.options[opts++]='\x04';
 460                 memcpy(&discover_packet.options[opts],&requested_address,sizeof(requested_address));
 461                 opts += sizeof(requested_address);
 462                 }
 463         discover_packet.options[opts++]=DHCP_OPTION_END;
 464
 465         /* send the DHCPDISCOVER packet to broadcast address */
 466         sockaddr_broadcast.sin_family=AF_INET;
 467         sockaddr_broadcast.sin_port=htons(DHCP_SERVER_PORT);
 468         sockaddr_broadcast.sin_addr.s_addr=INADDR_BROADCAST;
 469         bzero(&sockaddr_broadcast.sin_zero,sizeof(sockaddr_broadcast.sin_zero));
 470
 471
 472         if(verbose){
 473                 printf(_("DHCPDISCOVER to %s port %d\n"),inet_ntoa(sockaddr_broadcast.sin_addr),ntohs(sockaddr_broadcast.sin_port));
 474                 printf("DHCPDISCOVER XID: %lu (0x%X)\n",ntohl(discover_packet.xid),ntohl(discover_packet.xid));
 475                 printf("DHCDISCOVER ciaddr:  %s\n",inet_ntoa(discover_packet.ciaddr));
 476                 printf("DHCDISCOVER yiaddr:  %s\n",inet_ntoa(discover_packet.yiaddr));
 477                 printf("DHCDISCOVER siaddr:  %s\n",inet_ntoa(discover_packet.siaddr));
 478                 printf("DHCDISCOVER giaddr:  %s\n",inet_ntoa(discover_packet.giaddr));
 479                 }
 480
 481         /* send the DHCPDISCOVER packet out */
 482         send_dhcp_packet(&discover_packet,sizeof(discover_packet),sock,&sockaddr_broadcast);
 483
 484         if(verbose)
 485                 printf("\n\n");
 486
 487         return OK;
 488         }
 489
 490
 491
 492
 493 /* waits for a DHCPOFFER message from one or more DHCP servers */
 494 int get_dhcp_offer(int sock){
 495         dhcp_packet offer_packet;
 496         struct sockaddr_in source;
 497         struct sockaddr_in via;
 498         int result=OK;
 499         int responses=0;
 500         int x;
 501         time_t start_time;
 502         time_t current_time;
 503
 504         time(&start_time);
 505
 506         /* receive as many responses as we can */
 507         for(responses=0,valid_responses=0;;){
 508
 509                 time(&current_time);
 510                 if((current_time-start_time)>=dhcpoffer_timeout)
 511                         break;
 512
 513                 if(verbose)
 514                         printf("\n\n");
 515
 516                 bzero(&source,sizeof(source));
 517                 bzero(&via,sizeof(via));
 518                 bzero(&offer_packet,sizeof(offer_packet));
 519
 520                 result=OK;
 521                 result=receive_dhcp_packet(&offer_packet,sizeof(offer_packet),sock,dhcpoffer_timeout,&source);
 522
 523                 if(result!=OK){
 524                         if(verbose)
 525                                 printf(_("Result=ERROR\n"));
 526
 527                         continue;
 528                         }
 529                 else{
 530                         if(verbose)
 531                                 printf(_("Result=OK\n"));
 532
 533                         responses++;
 534                         }
 535
 536                 /* The "source" is either a server or a relay. */
 537                 /* Save a copy of "source" into "via" even if it's via itself */
 538                 memcpy(&via,&source,sizeof(source)) ;
 539
 540                 /* If siaddr is non-zero, set "source" to siaddr */
 541                 if(offer_packet.siaddr.s_addr != 0L){
 542                         source.sin_addr.s_addr = offer_packet.siaddr.s_addr ;
 543                         }
 544
 545                 if(verbose){
 546                         printf(_("DHCPOFFER from IP address %s"),inet_ntoa(source.sin_addr));
 547                         printf(_(" via %s\n"),inet_ntoa(via.sin_addr));
 548                         printf("DHCPOFFER XID: %lu (0x%X)\n",ntohl(offer_packet.xid),ntohl(offer_packet.xid));
 549                         }
 550
 551                 /* check packet xid to see if its the same as the one we used in the discover packet */
 552                 if(ntohl(offer_packet.xid)!=packet_xid){
 553                         if(verbose)
 554                                 printf(_("DHCPOFFER XID (%lu) did not match DHCPDISCOVER XID (%lu) - ignoring packet\n"),ntohl(offer_packet.xid),packet_xid);
 555
 556                         continue;
 557                         }
 558
 559                 /* check hardware address */
 560                 result=OK;
 561                 if(verbose)
 562                         printf("DHCPOFFER chaddr: ");
 563
 564                 for(x=0;x<ETHERNET_HARDWARE_ADDRESS_LENGTH;x++){
 565                         if(verbose)
 566                                 printf("%02X",(unsigned char)offer_packet.chaddr[x]);
 567
 568                         if(offer_packet.chaddr[x]!=client_hardware_address[x])
 569                                 result=ERROR;
 570                         }
 571                 if(verbose)
 572                         printf("\n");
 573
 574                 if(result==ERROR){
 575                         if(verbose)
 576                                 printf(_("DHCPOFFER hardware address did not match our own - ignoring packet\n"));
 577
 578                         continue;
 579                         }
 580
 581                 if(verbose){
 582                         printf("DHCPOFFER ciaddr: %s\n",inet_ntoa(offer_packet.ciaddr));
 583                         printf("DHCPOFFER yiaddr: %s\n",inet_ntoa(offer_packet.yiaddr));
 584                         printf("DHCPOFFER siaddr: %s\n",inet_ntoa(offer_packet.siaddr));
 585                         printf("DHCPOFFER giaddr: %s\n",inet_ntoa(offer_packet.giaddr));
 586                         }
 587
 588                 add_dhcp_offer(source.sin_addr,&offer_packet);
 589
 590                 valid_responses++;
 591                 }
 592
 593         if(verbose){
 594                 printf(_("Total responses seen on the wire: %d\n"),responses);
 595                 printf(_("Valid responses for this machine: %d\n"),valid_responses);
 596                 }
 597
 598         return OK;
 599         }
 600
 601
 602
 603 /* sends a DHCP packet */
 604 int send_dhcp_packet(void *buffer, int buffer_size, int sock, struct sockaddr_in *dest){
 605         int result;
 606
 607         result=sendto(sock,(char *)buffer,buffer_size,0,(struct sockaddr *)dest,sizeof(*dest));
 608
 609         if(verbose)
 610                 printf(_("send_dhcp_packet result: %d\n"),result);
 611
 612         if(result<0)
 613                 return ERROR;
 614
 615         return OK;
 616         }
 617
 618
 619
 620 /* receives a DHCP packet */
 621 int receive_dhcp_packet(void *buffer, int buffer_size, int sock, int timeout, struct sockaddr_in *address){
 622         struct timeval tv;
 623         fd_set readfds;
 624         int recv_result;
 625         socklen_t address_size;
 626         struct sockaddr_in source_address;
 627
 628
 629         /* wait for data to arrive (up time timeout) */
 630         tv.tv_sec=timeout;
 631         tv.tv_usec=0;
 632         FD_ZERO(&readfds);
 633         FD_SET(sock,&readfds);
 634         select(sock+1,&readfds,NULL,NULL,&tv);
 635
 636         /* make sure some data has arrived */
 637         if(!FD_ISSET(sock,&readfds)){
 638                 if(verbose)
 639                         printf(_("No (more) data received\n"));
 640                 return ERROR;
 641                 }
 642
 643         else{
 644
 645                 /* 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
 646                    not being interpreted correctly.  sigh... */
 647                 bzero(&source_address,sizeof(source_address));
 648                 address_size=sizeof(source_address);
 649                 recv_result=recvfrom(sock,(char *)buffer,buffer_size,MSG_PEEK,(struct sockaddr *)&source_address,&address_size);
 650                 if(verbose)
 651                         printf("recv_result_1: %d\n",recv_result);
 652                 recv_result=recvfrom(sock,(char *)buffer,buffer_size,0,(struct sockaddr *)&source_address,&address_size);
 653                 if(verbose)
 654                         printf("recv_result_2: %d\n",recv_result);
 655
 656                 if(recv_result==-1){
 657                         if(verbose){
 658                                 printf(_("recvfrom() failed, "));
 659                                 printf("errno: (%d) -> %s\n",errno,strerror(errno));
 660                                 }
 661                         return ERROR;
 662                         }
 663                 else{
 664                         if(verbose){
 665                                 printf(_("receive_dhcp_packet() result: %d\n"),recv_result);
 666                                 printf(_("receive_dhcp_packet() source: %s\n"),inet_ntoa(source_address.sin_addr));
 667                                 }
 668
 669                         memcpy(address,&source_address,sizeof(source_address));
 670                         return OK;
 671                         }
 672                 }
 673
 674         return OK;
 675         }
 676
 677
 678 /* creates a socket for DHCP communication */
 679 int create_dhcp_socket(void){
 680         struct sockaddr_in myname;
 681         struct ifreq interface;
 682         int sock;
 683         int flag=1;
 684
 685         /* Set up the address we're going to bind to. */
 686         bzero(&myname,sizeof(myname));
 687         myname.sin_family=AF_INET;
 688         myname.sin_port=htons(DHCP_CLIENT_PORT);
 689         myname.sin_addr.s_addr=INADDR_ANY;                 /* listen on any address */
 690         bzero(&myname.sin_zero,sizeof(myname.sin_zero));
 691
 692         /* create a socket for DHCP communications */
 693         sock=socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP);
 694         if(sock<0){
 695                 printf(_("Error: Could not create socket!\n"));
 696                 exit(STATE_UNKNOWN);
 697                 }
 698
 699         if(verbose)
 700                 printf("DHCP socket: %d\n",sock);
 701
 702         /* set the reuse address flag so we don't get errors when restarting */
 703         flag=1;
 704         if(setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,(char *)&flag,sizeof(flag))<0){
 705                 printf(_("Error: Could not set reuse address option on DHCP socket!\n"));
 706                 exit(STATE_UNKNOWN);
 707                 }
 708
 709         /* set the broadcast option - we need this to listen to DHCP broadcast messages */
 710         if(setsockopt(sock,SOL_SOCKET,SO_BROADCAST,(char *)&flag,sizeof flag)<0){
 711                 printf(_("Error: Could not set broadcast option on DHCP socket!\n"));
 712                 exit(STATE_UNKNOWN);
 713                 }
 714
 715         /* bind socket to interface */
 716 #if defined(__linux__)
 717         strncpy(interface.ifr_ifrn.ifrn_name,network_interface_name,IFNAMSIZ);
 718         if(setsockopt(sock,SOL_SOCKET,SO_BINDTODEVICE,(char *)&interface,sizeof(interface))<0){
 719                 printf(_("Error: Could not bind socket to interface %s.  Check your privileges...\n"),network_interface_name);
 720                 exit(STATE_UNKNOWN);
 721                 }
 722
 723 #else
 724         strncpy(interface.ifr_name,network_interface_name,IFNAMSIZ);
 725 #endif
 726
 727         /* bind the socket */
 728         if(bind(sock,(struct sockaddr *)&myname,sizeof(myname))<0){
 729                 printf(_("Error: Could not bind to DHCP socket (port %d)!  Check your privileges...\n"),DHCP_CLIENT_PORT);
 730                 exit(STATE_UNKNOWN);
 731                 }
 732
 733         return sock;
 734         }
 735
 736
 737 /* closes DHCP socket */
 738 int close_dhcp_socket(int sock){
 739
 740         close(sock);
 741
 742         return OK;
 743         }
 744
 745
 746 /* adds a requested server address to list in memory */
 747 int add_requested_server(struct in_addr server_address){
 748         requested_server *new_server;
 749
 750         new_server=(requested_server *)malloc(sizeof(requested_server));
 751         if(new_server==NULL)
 752                 return ERROR;
 753
 754         new_server->server_address=server_address;
 755         new_server->answered=FALSE;
 756
 757         new_server->next=requested_server_list;
 758         requested_server_list=new_server;
 759
 760         requested_servers++;
 761
 762         if(verbose)
 763                 printf(_("Requested server address: %s\n"),inet_ntoa(new_server->server_address));
 764
 765         return OK;
 766         }
 767
 768
 769
 770
 771 /* adds a DHCP OFFER to list in memory */
 772 int add_dhcp_offer(struct in_addr source,dhcp_packet *offer_packet){
 773         dhcp_offer *new_offer;
 774         int x;
 775         unsigned option_type;
 776         unsigned option_length;
 777         struct in_addr serv_ident = {0};
 778
 779         if(offer_packet==NULL)
 780                 return ERROR;
 781
 782         /* process all DHCP options present in the packet */
 783         for(x=4;x<MAX_DHCP_OPTIONS_LENGTH;){
 784
 785                 /* end of options (0 is really just a pad, but bail out anyway) */
 786                 if((int)offer_packet->options[x]==-1 || (int)offer_packet->options[x]==0)
 787                         break;
 788
 789                 /* get option type */
 790                 option_type=offer_packet->options[x++];
 791
 792                 /* get option length */
 793                 option_length=offer_packet->options[x++];
 794
 795                 if(verbose)
 796                         printf("Option: %d (0x%02X)\n",option_type,option_length);
 797
 798                 /* get option data */
 799                 switch(option_type){
 800                 case DHCP_OPTION_LEASE_TIME:
 801                         memcpy(&dhcp_lease_time, &offer_packet->options[x],sizeof(dhcp_lease_time));
 802                         dhcp_lease_time = ntohl(dhcp_lease_time);
 803                         break;
 804                 case DHCP_OPTION_RENEWAL_TIME:
 805                         memcpy(&dhcp_renewal_time, &offer_packet->options[x],sizeof(dhcp_renewal_time));
 806                         dhcp_renewal_time = ntohl(dhcp_renewal_time);
 807                         break;
 808                 case DHCP_OPTION_REBINDING_TIME:
 809                         memcpy(&dhcp_rebinding_time, &offer_packet->options[x],sizeof(dhcp_rebinding_time));
 810                         dhcp_rebinding_time = ntohl(dhcp_rebinding_time);
 811                         break;
 812                 case DHCP_OPTION_SERVER_IDENTIFIER:
 813                         memcpy(&serv_ident.s_addr, &offer_packet->options[x],sizeof(serv_ident.s_addr));
 814                         break;
 815                         }
 816
 817                 /* skip option data we're ignoring */
 818                 if(option_type!=DHCP_OPTION_REBINDING_TIME)
 819                         x+=option_length;
 820                 }
 821
 822         if(verbose){
 823                 if(dhcp_lease_time==DHCP_INFINITE_TIME)
 824                         printf(_("Lease Time: Infinite\n"));
 825                 else
 826                         printf(_("Lease Time: %lu seconds\n"),(unsigned long)dhcp_lease_time);
 827                 if(dhcp_renewal_time==DHCP_INFINITE_TIME)
 828                         printf(_("Renewal Time: Infinite\n"));
 829                 else
 830                         printf(_("Renewal Time: %lu seconds\n"),(unsigned long)dhcp_renewal_time);
 831                 if(dhcp_rebinding_time==DHCP_INFINITE_TIME)
 832                         printf(_("Rebinding Time: Infinite\n"));
 833                 printf(_("Rebinding Time: %lu seconds\n"),(unsigned long)dhcp_rebinding_time);
 834                 }
 835
 836         new_offer=(dhcp_offer *)malloc(sizeof(dhcp_offer));
 837
 838         if(new_offer==NULL)
 839                 return ERROR;
 840
 841         /*
 842          * RFC 2131 (2.) says: "DHCP clarifies the interpretation of the
 843          * 'siaddr' field as the address of the server to use in the next step
 844          * of the client's bootstrap process.  A DHCP server may return its own
 845          * address in the 'siaddr' field, if the server is prepared to supply
 846          * the next bootstrap service (e.g., delivery of an operating system
 847          * executable image).  A DHCP server always returns its own address in
 848          * the 'server identifier' option."  'serv_ident' is the 'server
 849          * identifier' option, 'source' is the 'siaddr' field or (if 'siaddr'
 850          * wasn't available) the IP address we received the DHCPOFFER from.  If
 851          * 'serv_ident' isn't available for some reason, we use 'source'.
 852          */
 853         new_offer->server_address=serv_ident.s_addr?serv_ident:source;
 854         new_offer->offered_address=offer_packet->yiaddr;
 855         new_offer->lease_time=dhcp_lease_time;
 856         new_offer->renewal_time=dhcp_renewal_time;
 857         new_offer->rebinding_time=dhcp_rebinding_time;
 858
 859
 860         if(verbose){
 861                 printf(_("Added offer from server @ %s"),inet_ntoa(new_offer->server_address));
 862                 printf(_(" of IP address %s\n"),inet_ntoa(new_offer->offered_address));
 863                 }
 864
 865         /* add new offer to head of list */
 866         new_offer->next=dhcp_offer_list;
 867         dhcp_offer_list=new_offer;
 868
 869         return OK;
 870         }
 871
 872
 873 /* frees memory allocated to DHCP OFFER list */
 874 int free_dhcp_offer_list(void){
 875         dhcp_offer *this_offer;
 876         dhcp_offer *next_offer;
 877
 878         for(this_offer=dhcp_offer_list;this_offer!=NULL;this_offer=next_offer){
 879                 next_offer=this_offer->next;
 880                 free(this_offer);
 881                 }
 882
 883         return OK;
 884         }
 885
 886
 887 /* frees memory allocated to requested server list */
 888 int free_requested_server_list(void){
 889         requested_server *this_server;
 890         requested_server *next_server;
 891
 892         for(this_server=requested_server_list;this_server!=NULL;this_server=next_server){
 893                 next_server=this_server->next;
 894                 free(this_server);
 895                 }
 896
 897         return OK;
 898         }
 899
 900
 901 /* gets state and plugin output to return */
 902 int get_results(void){
 903         dhcp_offer *temp_offer;
 904         requested_server *temp_server;
 905         int result;
 906         u_int32_t max_lease_time=0;
 907
 908         received_requested_address=FALSE;
 909
 910         /* checks responses from requested servers */
 911         requested_responses=0;
 912         if(requested_servers>0){
 913
 914                 for(temp_server=requested_server_list;temp_server!=NULL;temp_server=temp_server->next){
 915
 916                         for(temp_offer=dhcp_offer_list;temp_offer!=NULL;temp_offer=temp_offer->next){
 917
 918                                 /* get max lease time we were offered */
 919                                 if(temp_offer->lease_time>max_lease_time || temp_offer->lease_time==DHCP_INFINITE_TIME)
 920                                         max_lease_time=temp_offer->lease_time;
 921
 922                                 /* see if we got the address we requested */
 923                                 if(!memcmp(&requested_address,&temp_offer->offered_address,sizeof(requested_address)))
 924                                         received_requested_address=TRUE;
 925
 926                                 /* see if the servers we wanted a response from talked to us or not */
 927                                 if(!memcmp(&temp_offer->server_address,&temp_server->server_address,sizeof(temp_server->server_address))){
 928                                         if(verbose){
 929                                                 printf(_("DHCP Server Match: Offerer=%s"),inet_ntoa(temp_offer->server_address));
 930                                                 printf(_(" Requested=%s"),inet_ntoa(temp_server->server_address));
 931                                                 if(temp_server->answered)
 932                                                         printf(_(" (duplicate)"));
 933                                                 printf(_("\n"));
 934                                                 }
 935                                         if(temp_server->answered == FALSE){
 936                                                 requested_responses++;
 937                                                 temp_server->answered=TRUE;
 938                                                 }
 939                                         }
 940                                 }
 941                         }
 942
 943                 }
 944
 945         /* else check and see if we got our requested address from any server */
 946         else{
 947
 948                 for(temp_offer=dhcp_offer_list;temp_offer!=NULL;temp_offer=temp_offer->next){
 949
 950                         /* get max lease time we were offered */
 951                         if(temp_offer->lease_time>max_lease_time || temp_offer->lease_time==DHCP_INFINITE_TIME)
 952                                 max_lease_time=temp_offer->lease_time;
 953
 954                         /* see if we got the address we requested */
 955                         if(!memcmp(&requested_address,&temp_offer->offered_address,sizeof(requested_address)))
 956                                 received_requested_address=TRUE;
 957                         }
 958                 }
 959
 960         result=STATE_OK;
 961         if(valid_responses==0)
 962                 result=STATE_CRITICAL;
 963         else if(requested_servers>0 && requested_responses==0)
 964                 result=STATE_CRITICAL;
 965         else if(requested_responses<requested_servers)
 966                 result=STATE_WARNING;
 967         else if(request_specific_address==TRUE && received_requested_address==FALSE)
 968                 result=STATE_WARNING;
 969
 970         if(result==0)               /* garrett honeycutt 2005 */
 971                 printf("OK: ");
 972         else if(result==1)
 973                 printf("WARNING: ");
 974         else if(result==2)
 975                 printf("CRITICAL: ");
 976         else if(result==3)
 977                 printf("UNKNOWN: ");
 978
 979         /* we didn't receive any DHCPOFFERs */
 980         if(dhcp_offer_list==NULL){
 981                 printf(_("No DHCPOFFERs were received.\n"));
 982                 return result;
 983                 }
 984
 985         printf(_("Received %d DHCPOFFER(s)"),valid_responses);
 986
 987         if(requested_servers>0)
 988                 printf(_(", %s%d of %d requested servers responded"),((requested_responses<requested_servers) && requested_responses>0)?"only ":"",requested_responses,requested_servers);
 989
 990         if(request_specific_address==TRUE)
 991                 printf(_(", requested address (%s) was %soffered"),inet_ntoa(requested_address),(received_requested_address==TRUE)?"":_("not "));
 992
 993         printf(_(", max lease time = "));
 994         if(max_lease_time==DHCP_INFINITE_TIME)
 995                 printf(_("Infinity"));
 996         else
 997                 printf("%lu sec",(unsigned long)max_lease_time);
 998
 999         printf(".\n");
1000
1001         return result;
1002         }
1003
1004
1005 /* process command-line arguments */
1006 int process_arguments(int argc, char **argv){
1007         int c;
1008
1009         if(argc<1)
1010                 return ERROR;
1011
1012         c=0;
1013         while((c+=(call_getopt(argc-c,&argv[c])))<argc){
1014
1015                 /*
1016                 if(is_option(argv[c]))
1017                         continue;
1018                 */
1019                 }
1020
1021         return validate_arguments();
1022         }
1023
1024
1025
1026 int call_getopt(int argc, char **argv){
1027         int c=0;
1028         int i=0;
1029         struct in_addr ipaddress;
1030
1031         int option_index = 0;
1032         static struct option long_options[] =
1033         {
1034                 {"serverip",       required_argument,0,'s'},
1035                 {"requestedip",    required_argument,0,'r'},
1036                 {"timeout",        required_argument,0,'t'},
1037                 {"interface",      required_argument,0,'i'},
1038                 {"verbose",        no_argument,      0,'v'},
1039                 {"version",        no_argument,      0,'V'},
1040                 {"help",           no_argument,      0,'h'},
1041                 {0,0,0,0}
1042         };
1043
1044         while(1){
1045                 c=getopt_long(argc,argv,"+hVvt:s:r:t:i:",long_options,&option_index);
1046
1047                 i++;
1048
1049                 if(c==-1||c==EOF||c==1)
1050                         break;
1051
1052                 switch(c){
1053                 case 'w':
1054                 case 'r':
1055                 case 't':
1056                 case 'i':
1057                         i++;
1058                         break;
1059                 default:
1060                         break;
1061                         }
1062
1063                 switch(c){
1064
1065                 case 's': /* DHCP server address */
1066                         if(inet_aton(optarg,&ipaddress))
1067                                 add_requested_server(ipaddress);
1068                         /*
1069                         else
1070                                 usage("Invalid server IP address\n");
1071                         */
1072                         break;
1073
1074                 case 'r': /* address we are requested from DHCP servers */
1075                         if(inet_aton(optarg,&ipaddress)){
1076                                 requested_address=ipaddress;
1077                                 request_specific_address=TRUE;
1078                                 }
1079                         /*
1080                         else
1081                                 usage("Invalid requested IP address\n");
1082                         */
1083                         break;
1084
1085                 case 't': /* timeout */
1086
1087                         /*
1088                         if(is_intnonneg(optarg))
1089                         */
1090                         if(atoi(optarg)>0)
1091                                 dhcpoffer_timeout=atoi(optarg);
1092                         /*
1093                         else
1094                                 usage("Time interval must be a nonnegative integer\n");
1095                         */
1096                         break;
1097
1098                 case 'i': /* interface name */
1099
1100                         strncpy(network_interface_name,optarg,sizeof(network_interface_name)-1);
1101                         network_interface_name[sizeof(network_interface_name)-1]='\x0';
1102
1103                         break;
1104
1105                 case 'V': /* version */
1106                         print_revision(progname,revision);
1107                         exit(STATE_OK);
1108
1109                 case 'h': /* help */
1110                         print_help();
1111                         exit(STATE_OK);
1112
1113                 case 'v': /* verbose */
1114                         verbose=1;
1115                         break;
1116
1117                 case '?': /* help */
1118                         usage5 ();
1119                         break;
1120
1121                 default:
1122                         break;
1123                         }
1124                 }
1125
1126         return i;
1127         }
1128
1129
1130 int validate_arguments(void){
1131
1132         return OK;
1133         }
1134
1135
1136 #if defined(__sun__) || defined(__solaris__) || defined(__hpux__)
1137 /* Kompf 2000-2003      see ACKNOWLEDGEMENTS */
1138
1139 /* get a message from a stream; return type of message */
1140 static int get_msg(int fd){
1141         int flags = 0;
1142         int res, ret;
1143         ctl_area[0] = 0;
1144         dat_area[0] = 0;
1145         ret = 0;
1146         res = getmsg(fd, &ctl, &dat, &flags);
1147
1148         if(res < 0){
1149                 if(errno == EINTR){
1150                         return(GOT_INTR);
1151                         }
1152                 else{
1153                         printf("%s\n", "get_msg FAILED.");
1154                         return(GOT_ERR);
1155                         }
1156                 }
1157         if(ctl.len > 0){
1158                 ret |= GOT_CTRL;
1159                 }
1160         if(dat.len > 0){
1161                 ret |= GOT_DATA;
1162                 }
1163
1164         return(ret);
1165         }
1166
1167 /* verify that dl_primitive in ctl_area = prim */
1168 static int check_ctrl(int prim){
1169         dl_error_ack_t *err_ack = (dl_error_ack_t *)ctl_area;
1170
1171         if(err_ack->dl_primitive != prim){
1172                 printf(_("Error: DLPI stream API failed to get MAC in check_ctrl: %s.\n"), strerror(errno));
1173                 exit(STATE_UNKNOWN);
1174                 }
1175
1176         return 0;
1177         }
1178
1179 /* put a control message on a stream */
1180 static int put_ctrl(int fd, int len, int pri){
1181
1182         ctl.len = len;
1183         if(putmsg(fd, &ctl, 0, pri) < 0){
1184                 printf(_("Error: DLPI stream API failed to get MAC in put_ctrl/putmsg(): %s.\n"), strerror(errno));
1185                 exit(STATE_UNKNOWN);
1186                 }
1187
1188         return  0;
1189         }
1190
1191 /* put a control + data message on a stream */
1192 static int put_both(int fd, int clen, int dlen, int pri){
1193
1194         ctl.len = clen;
1195         dat.len = dlen;
1196         if(putmsg(fd, &ctl, &dat, pri) < 0){
1197                 printf(_("Error: DLPI stream API failed to get MAC in put_both/putmsg().\n"), strerror(errno));
1198                 exit(STATE_UNKNOWN);
1199                 }
1200
1201         return  0;
1202         }
1203
1204 /* open file descriptor and attach */
1205 static int dl_open(const char *dev, int unit, int *fd){
1206         dl_attach_req_t *attach_req = (dl_attach_req_t *)ctl_area;
1207
1208         if((*fd = open(dev, O_RDWR)) == -1){
1209                 printf(_("Error: DLPI stream API failed to get MAC in dl_attach_req/open(%s..): %s.\n"), dev, strerror(errno));
1210                 exit(STATE_UNKNOWN);
1211                 }
1212         attach_req->dl_primitive = DL_ATTACH_REQ;
1213         attach_req->dl_ppa = unit;
1214         put_ctrl(*fd, sizeof(dl_attach_req_t), 0);
1215         get_msg(*fd);
1216         return check_ctrl(DL_OK_ACK);
1217         }
1218
1219 /* send DL_BIND_REQ */
1220 static int dl_bind(int fd, int sap, u_char *addr){
1221         dl_bind_req_t *bind_req = (dl_bind_req_t *)ctl_area;
1222         dl_bind_ack_t *bind_ack = (dl_bind_ack_t *)ctl_area;
1223
1224         bind_req->dl_primitive = DL_BIND_REQ;
1225         bind_req->dl_sap = sap;
1226         bind_req->dl_max_conind = 1;
1227         bind_req->dl_service_mode = DL_CLDLS;
1228         bind_req->dl_conn_mgmt = 0;
1229         bind_req->dl_xidtest_flg = 0;
1230         put_ctrl(fd, sizeof(dl_bind_req_t), 0);
1231         get_msg(fd);
1232         if (GOT_ERR == check_ctrl(DL_BIND_ACK)){
1233                 printf(_("Error: DLPI stream API failed to get MAC in dl_bind/check_ctrl(): %s.\n"), strerror(errno));
1234                 exit(STATE_UNKNOWN);
1235                 }
1236         bcopy((u_char *)bind_ack + bind_ack->dl_addr_offset, addr,
1237               bind_ack->dl_addr_length);
1238
1239         return 0;
1240         }
1241
1242 /***********************************************************************
1243  * interface:
1244  * function mac_addr_dlpi - get the mac address of the interface with
1245  *                          type dev (eg lnc, hme) and unit (0, 1 ..)
1246  *
1247  * parameter: addr: an array of six bytes, has to be allocated by the caller
1248  *
1249  * return: 0 if OK, -1 if the address could not be determined
1250  *
1251  *
1252  ***********************************************************************/
1253
1254 long mac_addr_dlpi( const char *dev, int unit, u_char  *addr){
1255         int fd;
1256         u_char mac_addr[25];
1257
1258         if(GOT_ERR != dl_open(dev, unit, &fd)){
1259                 if(GOT_ERR != dl_bind(fd, INSAP, mac_addr)){
1260                         bcopy( mac_addr, addr, 6);
1261                         return 0;
1262                         }
1263                 }
1264         close(fd);
1265
1266         return -1;
1267         }
1268
1269 /* Kompf 2000-2003 */
1270 #endif
1271
1272
1273 /* print usage help */
1274 void print_help(void){
1275
1276         print_revision(progname,revision);
1277
1278         printf("Copyright (c) 2001-2004 Ethan Galstad (nagios@nagios.org)\n");
1279         printf (COPYRIGHT, copyright, email);
1280
1281         printf("%s\n", _("This plugin tests the availability of DHCP servers on a network."));
1282
1283   printf ("\n\n");
1284
1285         print_usage();
1286
1287         printf (_(UT_HELP_VRSN));
1288
1289         printf (_(UT_VERBOSE));
1290
1291         printf (" %s\n", "-s, --serverip=IPADDRESS");
1292   printf ("    %s\n", _("IP address of DHCP server that we must hear from"));
1293   printf (" %s\n", "-r, --requestedip=IPADDRESS");
1294   printf ("    %s\n", _("IP address that should be offered by at least one DHCP server"));
1295   printf (" %s\n", "-t, --timeout=INTEGER");
1296   printf ("    %s\n", _("Seconds to wait for DHCPOFFER before timeout occurs"));
1297   printf (" %s\n", "-i, --interface=STRING");
1298   printf ("    %s\n", _("Interface to to use for listening (i.e. eth0)"));
1299
1300         return;
1301         }
1302
1303
1304 void
1305 print_usage(void){
1306
1307   printf (_("Usage:"));
1308   printf ("%s [-s serverip] [-r requestedip] [-t timeout] [-i interface] [-v]\n",progname);
1309
1310         return;
1311         }
1312
1313
1314