plugins/check_dhcp.c

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