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
 295         /* Code from getmac.c posted at http://lists.freebsd.org/pipermail/freebsd-hackers/2004-June/007415.html
 296          * by Alecs King based on Unix Network programming Ch 17
 297          */
 298
 299         int                     mib[6], len;
 300         char                    *buf;
 301         unsigned char           *ptr;
 302         struct if_msghdr        *ifm;
 303         struct sockaddr_dl      *sdl;
 304
 305         mib[0] = CTL_NET;
 306         mib[1] = AF_ROUTE;
 307         mib[2] = 0;
 308         mib[3] = AF_LINK;
 309         mib[4] = NET_RT_IFLIST;
 310
 311         if ((mib[5] = if_nametoindex(interface_name)) == 0) {
 312                 printf("Error: if_nametoindex error - %s.\n", strerror(errno));
 313                 exit(STATE_UNKNOWN);
 314         }
 315
 316         if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0) {
 317                 printf("Error: Couldn't get hardware address from %s. sysctl 1 error - %s.\n", interface_name, strerror(errno));
 318                 exit(STATE_UNKNOWN);
 319         }
 320
 321         if ((buf = malloc(len)) == NULL) {
 322                 printf("Error: Couldn't get hardware address from interface %s. malloc error - %s.\n", interface_name, strerror(errno));
 323                 exit(4);
 324         }
 325
 326         if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
 327                 printf("Error: Couldn't get hardware address from %s. sysctl 2 error - %s.\n", interface_name, strerror(errno));
 328                 exit(STATE_UNKNOWN);
 329         }
 330
 331         ifm = (struct if_msghdr *)buf;
 332         sdl = (struct sockaddr_dl *)(ifm + 1);
 333         ptr = (unsigned char *)LLADDR(sdl);
 334         memcpy(&client_hardware_address[0], ptr, 6) ;
 335
 336 #elif defined(__sun__) || defined(__solaris__)
 337
 338         /*
 339         * Lifted from
 340         *
 341         * mac_addr_dlpi.c
 342         *
 343         * Copyright @2000, 2003 Martin Kompf, martin@kompf.de
 344         *
 345         * Return the MAC (ie, ethernet hardware) address by using the dlpi api.
 346         *
 347         */
 348
 349         long stat;
 350         char dev[20] = "/dev/";
 351         char *p;
 352         int unit;
 353
 354         for (p = interface_name; *p && isalpha(*p); p++)
 355                 /* no-op */ ;
 356         if ( p != '\0' ) {
 357                 unit = atoi(p) ;
 358                 *p = '\0' ;
 359                 strncat(dev, interface_name, 6) ;
 360         } else {
 361                 printf("Error: can't find unit number in interface_name (%s) - expecting TypeNumber eg lnc0.\n", interface_name);
 362                 exit(STATE_UNKNOWN);
 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
 370 #elif defined(__hpux__)
 371
 372         /* Martin Kompf again
 373          *
 374          * Nagios plugins thank you sincerely
 375          */
 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
 387 #else
 388         printf("Error: can't get MAC address for this architecture.\n");
 389         exit(STATE_UNKNOWN);
 390 #endif
 391
 392         if (verbose) {
 393                 printf( "Hardware address: ");
 394                 for (i=0; i<6; ++i)
 395                         printf("%2.2x", client_hardware_address[i]);
 396                 printf( "\n");
 397         }
 398
 399         return OK;
 400         }
 401
 402
 403 /* sends a DHCPDISCOVER broadcast message in an attempt to find DHCP servers */
 404 int send_dhcp_discover(int sock){
 405         dhcp_packet discover_packet;
 406         struct sockaddr_in sockaddr_broadcast;
 407
 408
 409         /* clear the packet data structure */
 410         bzero(&discover_packet,sizeof(discover_packet));
 411
 412
 413         /* boot request flag (backward compatible with BOOTP servers) */
 414         discover_packet.op=BOOTREQUEST;
 415
 416         /* hardware address type */
 417         discover_packet.htype=ETHERNET_HARDWARE_ADDRESS;
 418
 419         /* length of our hardware address */
 420         discover_packet.hlen=ETHERNET_HARDWARE_ADDRESS_LENGTH;
 421
 422         discover_packet.hops=0;
 423
 424         /* transaction id is supposed to be random */
 425         srand(time(NULL));
 426         packet_xid=random();
 427         discover_packet.xid=htonl(packet_xid);
 428
 429         /**** WHAT THE HECK IS UP WITH THIS?!?  IF I DON'T MAKE THIS CALL, ONLY ONE SERVER RESPONSE IS PROCESSED!!!! ****/
 430         /* downright bizzarre... */
 431         ntohl(discover_packet.xid);
 432
 433         /*discover_packet.secs=htons(65535);*/
 434         discover_packet.secs=0xFF;
 435
 436         /* tell server it should broadcast its response */
 437         discover_packet.flags=htons(DHCP_BROADCAST_FLAG);
 438
 439         /* our hardware address */
 440         memcpy(discover_packet.chaddr,client_hardware_address,ETHERNET_HARDWARE_ADDRESS_LENGTH);
 441
 442         /* first four bytes of options field is magic cookie (as per RFC 2132) */
 443         discover_packet.options[0]='\x63';
 444         discover_packet.options[1]='\x82';
 445         discover_packet.options[2]='\x53';
 446         discover_packet.options[3]='\x63';
 447
 448         /* DHCP message type is embedded in options field */
 449         discover_packet.options[4]=DHCP_OPTION_MESSAGE_TYPE;    /* DHCP message type option identifier */
 450         discover_packet.options[5]='\x01';               /* DHCP message option length in bytes */
 451         discover_packet.options[6]=DHCPDISCOVER;
 452
 453         /* the IP address we're requesting */
 454         if(request_specific_address==TRUE){
 455                 discover_packet.options[7]=DHCP_OPTION_REQUESTED_ADDRESS;
 456                 discover_packet.options[8]='\x04';
 457                 memcpy(&discover_packet.options[9],&requested_address,sizeof(requested_address));
 458                 }
 459
 460         /* send the DHCPDISCOVER packet to broadcast address */
 461         sockaddr_broadcast.sin_family=AF_INET;
 462         sockaddr_broadcast.sin_port=htons(DHCP_SERVER_PORT);
 463         sockaddr_broadcast.sin_addr.s_addr=INADDR_BROADCAST;
 464         bzero(&sockaddr_broadcast.sin_zero,sizeof(sockaddr_broadcast.sin_zero));
 465
 466
 467         if (verbose) {
 468                 printf("DHCPDISCOVER to %s port %d\n",inet_ntoa(sockaddr_broadcast.sin_addr),ntohs(sockaddr_broadcast.sin_port));
 469                 printf("DHCPDISCOVER XID: %lu (0x%X)\n",ntohl(discover_packet.xid),ntohl(discover_packet.xid));
 470                 printf("DHCDISCOVER ciaddr:  %s\n",inet_ntoa(discover_packet.ciaddr));
 471                 printf("DHCDISCOVER yiaddr:  %s\n",inet_ntoa(discover_packet.yiaddr));
 472                 printf("DHCDISCOVER siaddr:  %s\n",inet_ntoa(discover_packet.siaddr));
 473                 printf("DHCDISCOVER giaddr:  %s\n",inet_ntoa(discover_packet.giaddr));
 474         }
 475
 476         /* send the DHCPDISCOVER packet out */
 477         send_dhcp_packet(&discover_packet,sizeof(discover_packet),sock,&sockaddr_broadcast);
 478
 479         if (verbose)
 480                 printf("\n\n");
 481
 482         return OK;
 483         }
 484
 485
 486
 487
 488 /* waits for a DHCPOFFER message from one or more DHCP servers */
 489 int get_dhcp_offer(int sock){
 490         dhcp_packet offer_packet;
 491         struct sockaddr_in source;
 492         int result=OK;
 493         int timeout=1;
 494         int responses=0;
 495         int x;
 496         time_t start_time;
 497         time_t current_time;
 498
 499         time(&start_time);
 500
 501         /* receive as many responses as we can */
 502         for(responses=0,valid_responses=0;;){
 503
 504                 time(&current_time);
 505                 if((current_time-start_time)>=dhcpoffer_timeout)
 506                         break;
 507
 508                 if (verbose)
 509                         printf("\n\n");
 510
 511                 bzero(&source,sizeof(source));
 512                 bzero(&offer_packet,sizeof(offer_packet));
 513
 514                 result=OK;
 515                 result=receive_dhcp_packet(&offer_packet,sizeof(offer_packet),sock,dhcpoffer_timeout,&source);
 516
 517                 if(result!=OK){
 518                         if (verbose)
 519                                 printf("Result=ERROR\n");
 520
 521                         continue;
 522                         }
 523                 else{
 524                         if (verbose)
 525                                 printf("Result=OK\n");
 526
 527                         responses++;
 528                         }
 529
 530                 if (verbose) {
 531                         printf("DHCPOFFER from IP address %s\n",inet_ntoa(source.sin_addr));
 532                         printf("DHCPOFFER XID: %lu (0x%X)\n",ntohl(offer_packet.xid),ntohl(offer_packet.xid));
 533                 }
 534
 535                 /* check packet xid to see if its the same as the one we used in the discover packet */
 536                 if(ntohl(offer_packet.xid)!=packet_xid){
 537                         if (verbose)
 538                                 printf("DHCPOFFER XID (%lu) did not match DHCPDISCOVER XID (%lu) - ignoring packet\n",ntohl(offer_packet.xid),packet_xid);
 539
 540                         continue;
 541                         }
 542
 543                 /* check hardware address */
 544                 result=OK;
 545                 if (verbose)
 546                         printf("DHCPOFFER chaddr: ");
 547
 548                 for(x=0;x<ETHERNET_HARDWARE_ADDRESS_LENGTH;x++){
 549                         if (verbose)
 550                                 printf("%02X",(unsigned char)offer_packet.chaddr[x]);
 551
 552                         if(offer_packet.chaddr[x]!=client_hardware_address[x])
 553                                 result=ERROR;
 554                 }
 555                 if (verbose)
 556                         printf("\n");
 557
 558                 if(result==ERROR){
 559                         if (verbose)
 560                                 printf("DHCPOFFER hardware address did not match our own - ignoring packet\n");
 561
 562                         continue;
 563                         }
 564
 565                 if (verbose) {
 566                         printf("DHCPOFFER ciaddr: %s\n",inet_ntoa(offer_packet.ciaddr));
 567                         printf("DHCPOFFER yiaddr: %s\n",inet_ntoa(offer_packet.yiaddr));
 568                         printf("DHCPOFFER siaddr: %s\n",inet_ntoa(offer_packet.siaddr));
 569                         printf("DHCPOFFER giaddr: %s\n",inet_ntoa(offer_packet.giaddr));
 570                 }
 571
 572                 add_dhcp_offer(source.sin_addr,&offer_packet);
 573
 574                 valid_responses++;
 575                 }
 576
 577         if (verbose) {
 578                 printf("Total responses seen on the wire: %d\n",responses);
 579                 printf("Valid responses for this machine: %d\n",valid_responses);
 580         }
 581
 582         return OK;
 583         }
 584
 585
 586
 587 /* sends a DHCP packet */
 588 int send_dhcp_packet(void *buffer, int buffer_size, int sock, struct sockaddr_in *dest){
 589         struct sockaddr_in myname;
 590         int result;
 591
 592         result=sendto(sock,(char *)buffer,buffer_size,0,(struct sockaddr *)dest,sizeof(*dest));
 593
 594         if (verbose)
 595                 printf("send_dhcp_packet result: %d\n",result);
 596
 597         if(result<0)
 598                 return ERROR;
 599
 600         return OK;
 601         }
 602
 603
 604
 605 /* receives a DHCP packet */
 606 int receive_dhcp_packet(void *buffer, int buffer_size, int sock, int timeout, struct sockaddr_in *address){
 607         struct timeval tv;
 608         fd_set readfds;
 609         int recv_result;
 610         socklen_t address_size;
 611         struct sockaddr_in source_address;
 612
 613
 614         /* wait for data to arrive (up time timeout) */
 615         tv.tv_sec=timeout;
 616         tv.tv_usec=0;
 617         FD_ZERO(&readfds);
 618         FD_SET(sock,&readfds);
 619         select(sock+1,&readfds,NULL,NULL,&tv);
 620
 621         /* make sure some data has arrived */
 622         if(!FD_ISSET(sock,&readfds)){
 623                 if (verbose)
 624                         printf("No (more) data received\n");
 625                 return ERROR;
 626                 }
 627
 628         else{
 629
 630                 /* 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
 631                    not being interpreted correctly.  sigh... */
 632                 bzero(&source_address,sizeof(source_address));
 633                 address_size=sizeof(source_address);
 634                 recv_result=recvfrom(sock,(char *)buffer,buffer_size,MSG_PEEK,(struct sockaddr *)&source_address,&address_size);
 635                 if (verbose)
 636                         printf("recv_result_1: %d\n",recv_result);
 637                 recv_result=recvfrom(sock,(char *)buffer,buffer_size,0,(struct sockaddr *)&source_address,&address_size);
 638                 if (verbose)
 639                         printf("recv_result_2: %d\n",recv_result);
 640
 641                 if(recv_result==-1){
 642                         if (verbose) {
 643                                 printf("recvfrom() failed, ");
 644                                 printf("errno: (%d) -> %s\n",errno,strerror(errno));
 645                         }
 646                         return ERROR;
 647                         }
 648                 else{
 649                         if (verbose) {
 650                                 printf("receive_dhcp_packet() result: %d\n",recv_result);
 651                                 printf("receive_dhcp_packet() source: %s\n",inet_ntoa(source_address.sin_addr));
 652                         }
 653
 654                         memcpy(address,&source_address,sizeof(source_address));
 655                         return OK;
 656                         }
 657                 }
 658
 659         return OK;
 660         }
 661
 662
 663
 664 /* creates a socket for DHCP communication */
 665 int create_dhcp_socket(void){
 666         struct sockaddr_in myname;
 667         struct ifreq interface;
 668         int sock;
 669         int flag=1;
 670
 671         /* Set up the address we're going to bind to. */
 672         bzero(&myname,sizeof(myname));
 673         myname.sin_family=AF_INET;
 674         myname.sin_port=htons(DHCP_CLIENT_PORT);
 675         myname.sin_addr.s_addr=INADDR_ANY;                 /* listen on any address */
 676         bzero(&myname.sin_zero,sizeof(myname.sin_zero));
 677
 678         /* create a socket for DHCP communications */
 679         sock=socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP);
 680         if(sock<0){
 681                 printf("Error: Could not create socket!\n");
 682                 exit(STATE_UNKNOWN);
 683                 }
 684
 685         if (verbose)
 686                 printf("DHCP socket: %d\n",sock);
 687
 688         /* set the reuse address flag so we don't get errors when restarting */
 689         flag=1;
 690         if(setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,(char *)&flag,sizeof(flag))<0){
 691                 printf("Error: Could not set reuse address option on DHCP socket!\n");
 692                 exit(STATE_UNKNOWN);
 693                 }
 694
 695         /* set the broadcast option - we need this to listen to DHCP broadcast messages */
 696         if(setsockopt(sock,SOL_SOCKET,SO_BROADCAST,(char *)&flag,sizeof flag)<0){
 697                 printf("Error: Could not set broadcast option on DHCP socket!\n");
 698                 exit(STATE_UNKNOWN);
 699                 }
 700
 701         /* bind socket to interface */
 702 #if defined(__linux__)
 703         strncpy(interface.ifr_ifrn.ifrn_name,network_interface_name,IFNAMSIZ);
 704         if(setsockopt(sock,SOL_SOCKET,SO_BINDTODEVICE,(char *)&interface,sizeof(interface))<0){
 705                 printf("Error: Could not bind socket to interface %s.  Check your privileges...\n",network_interface_name);
 706                 exit(STATE_UNKNOWN);
 707                 }
 708
 709 #else
 710         strncpy(interface.ifr_name,network_interface_name,IFNAMSIZ);
 711 #endif
 712
 713         /* bind the socket */
 714         if(bind(sock,(struct sockaddr *)&myname,sizeof(myname))<0){
 715                 printf("Error: Could not bind to DHCP socket (port %d)!  Check your privileges...\n",DHCP_CLIENT_PORT);
 716                 exit(STATE_UNKNOWN);
 717                 }
 718
 719         return sock;
 720         }
 721
 722
 723
 724
 725
 726 /* closes DHCP socket */
 727 int close_dhcp_socket(int sock){
 728
 729         close(sock);
 730
 731         return OK;
 732         }
 733
 734
 735
 736
 737 /* adds a requested server address to list in memory */
 738 int add_requested_server(struct in_addr server_address){
 739         requested_server *new_server;
 740
 741         new_server=(requested_server *)malloc(sizeof(requested_server));
 742         if(new_server==NULL)
 743                 return ERROR;
 744
 745         new_server->server_address=server_address;
 746
 747         new_server->next=requested_server_list;
 748         requested_server_list=new_server;
 749
 750         requested_servers++;
 751
 752         if (verbose)
 753                 printf("Requested server address: %s\n",inet_ntoa(new_server->server_address));
 754
 755         return OK;
 756         }
 757
 758
 759
 760
 761 /* adds a DHCP OFFER to list in memory */
 762 int add_dhcp_offer(struct in_addr source,dhcp_packet *offer_packet){
 763         dhcp_offer *new_offer;
 764         int x;
 765         int y;
 766         unsigned option_type;
 767         unsigned option_length;
 768
 769         if(offer_packet==NULL)
 770                 return ERROR;
 771
 772         /* process all DHCP options present in the packet */
 773         for(x=4;x<MAX_DHCP_OPTIONS_LENGTH;){
 774
 775                 /* end of options (0 is really just a pad, but bail out anyway) */
 776                 if((int)offer_packet->options[x]==-1 || (int)offer_packet->options[x]==0)
 777                         break;
 778
 779                 /* get option type */
 780                 option_type=offer_packet->options[x++];
 781
 782                 /* get option length */
 783                 option_length=offer_packet->options[x++];
 784
 785                 if (verbose)
 786                         printf("Option: %d (0x%02X)\n",option_type,option_length);
 787
 788                 /* get option data */
 789                 if(option_type==DHCP_OPTION_LEASE_TIME)
 790                         dhcp_lease_time=ntohl(*((u_int32_t *)&offer_packet->options[x]));
 791                 if(option_type==DHCP_OPTION_RENEWAL_TIME)
 792                         dhcp_renewal_time=ntohl(*((u_int32_t *)&offer_packet->options[x]));
 793                 if(option_type==DHCP_OPTION_REBINDING_TIME)
 794                         dhcp_rebinding_time=ntohl(*((u_int32_t *)&offer_packet->options[x]));
 795
 796                 /* skip option data we're ignoring */
 797                 else
 798                         for(y=0;y<option_length;y++,x++);
 799                 }
 800
 801         if (verbose) {
 802                 if(dhcp_lease_time==DHCP_INFINITE_TIME)
 803                         printf("Lease Time: Infinite\n");
 804                 else
 805                         printf("Lease Time: %lu seconds\n",(unsigned long)dhcp_lease_time);
 806                 if(dhcp_renewal_time==DHCP_INFINITE_TIME)
 807                         printf("Renewal Time: Infinite\n");
 808                 else
 809                         printf("Renewal Time: %lu seconds\n",(unsigned long)dhcp_renewal_time);
 810                 if(dhcp_rebinding_time==DHCP_INFINITE_TIME)
 811                         printf("Rebinding Time: Infinite\n");
 812                 printf("Rebinding Time: %lu seconds\n",(unsigned long)dhcp_rebinding_time);
 813         }
 814
 815         new_offer=(dhcp_offer *)malloc(sizeof(dhcp_offer));
 816
 817         if(new_offer==NULL)
 818                 return ERROR;
 819
 820
 821         new_offer->server_address=source;
 822         new_offer->offered_address=offer_packet->yiaddr;
 823         new_offer->lease_time=dhcp_lease_time;
 824         new_offer->renewal_time=dhcp_renewal_time;
 825         new_offer->rebinding_time=dhcp_rebinding_time;
 826
 827
 828         if (verbose) {
 829                 printf("Added offer from server @ %s",inet_ntoa(new_offer->server_address));
 830                 printf(" of IP address %s\n",inet_ntoa(new_offer->offered_address));
 831         }
 832
 833         /* add new offer to head of list */
 834         new_offer->next=dhcp_offer_list;
 835         dhcp_offer_list=new_offer;
 836
 837         return OK;
 838         }
 839
 840
 841
 842
 843 /* frees memory allocated to DHCP OFFER list */
 844 int free_dhcp_offer_list(void){
 845         dhcp_offer *this_offer;
 846         dhcp_offer *next_offer;
 847
 848         for(this_offer=dhcp_offer_list;this_offer!=NULL;this_offer=next_offer){
 849                 next_offer=this_offer->next;
 850                 free(this_offer);
 851                 }
 852
 853         return OK;
 854         }
 855
 856
 857
 858
 859 /* frees memory allocated to requested server list */
 860 int free_requested_server_list(void){
 861         requested_server *this_server;
 862         requested_server *next_server;
 863
 864         for(this_server=requested_server_list;this_server!=NULL;this_server=next_server){
 865                 next_server=this_server->next;
 866                 free(this_server);
 867                 }
 868
 869         return OK;
 870         }
 871
 872
 873 /* gets state and plugin output to return */
 874 int get_results(void){
 875         dhcp_offer *temp_offer;
 876         requested_server *temp_server;
 877         int result;
 878         u_int32_t max_lease_time=0;
 879
 880         received_requested_address=FALSE;
 881
 882         /* checks responses from requested servers */
 883         requested_responses=0;
 884         if(requested_servers>0){
 885
 886                 for(temp_server=requested_server_list;temp_server!=NULL;temp_server=temp_server->next){
 887
 888                         for(temp_offer=dhcp_offer_list;temp_offer!=NULL;temp_offer=temp_offer->next){
 889
 890                                 /* get max lease time we were offered */
 891                                 if(temp_offer->lease_time>max_lease_time || temp_offer->lease_time==DHCP_INFINITE_TIME)
 892                                         max_lease_time=temp_offer->lease_time;
 893
 894                                 /* see if we got the address we requested */
 895                                 if(!memcmp(&requested_address,&temp_offer->offered_address,sizeof(requested_address)))
 896                                         received_requested_address=TRUE;
 897
 898                                 /* see if the servers we wanted a response from talked to us or not */
 899                                 if(!memcmp(&temp_offer->server_address,&temp_server->server_address,sizeof(temp_server->server_address))){
 900         if (verbose) {
 901                                         printf("DHCP Server Match: Offerer=%s",inet_ntoa(temp_offer->server_address));
 902                                         printf(" Requested=%s\n",inet_ntoa(temp_server->server_address));
 903         }
 904                                         requested_responses++;
 905                                         }
 906                                 }
 907                         }
 908
 909                 }
 910
 911         /* else check and see if we got our requested address from any server */
 912         else{
 913
 914                 for(temp_offer=dhcp_offer_list;temp_offer!=NULL;temp_offer=temp_offer->next){
 915
 916                         /* get max lease time we were offered */
 917                         if(temp_offer->lease_time>max_lease_time || temp_offer->lease_time==DHCP_INFINITE_TIME)
 918                                 max_lease_time=temp_offer->lease_time;
 919
 920                         /* see if we got the address we requested */
 921                         if(!memcmp(&requested_address,&temp_offer->offered_address,sizeof(requested_address)))
 922                                 received_requested_address=TRUE;
 923                         }
 924                 }
 925
 926         result=STATE_OK;
 927         if(valid_responses==0)
 928                 result=STATE_CRITICAL;
 929         else if(requested_servers>0 && requested_responses==0)
 930                 result=STATE_CRITICAL;
 931         else if(requested_responses<requested_servers)
 932                 result=STATE_WARNING;
 933         else if(request_specific_address==TRUE && received_requested_address==FALSE)
 934                 result=STATE_WARNING;
 935
 936
 937         printf("DHCP %s: ",(result==STATE_OK)?"ok":"problem");
 938
 939         /* we didn't receive any DHCPOFFERs */
 940         if(dhcp_offer_list==NULL){
 941                 printf("No DHCPOFFERs were received.\n");
 942                 return result;
 943                 }
 944
 945         printf("Received %d DHCPOFFER(s)",valid_responses);
 946
 947         if(requested_servers>0)
 948                 printf(", %s%d of %d requested servers responded",((requested_responses<requested_servers) && requested_responses>0)?"only ":"",requested_responses,requested_servers);
 949
 950         if(request_specific_address==TRUE)
 951                 printf(", requested address (%s) was %soffered",inet_ntoa(requested_address),(received_requested_address==TRUE)?"":"not ");
 952
 953         printf(", max lease time = ");
 954         if(max_lease_time==DHCP_INFINITE_TIME)
 955                 printf("Infinity");
 956         else
 957                 printf("%lu sec",(unsigned long)max_lease_time);
 958
 959         printf(".\n");
 960
 961         return result;
 962         }
 963
 964
 965
 966
 967
 968
 969 /* print usage help */
 970 void print_help(void){
 971
 972         /*print_revision(progname,"$Revision$");*/
 973
 974         printf("Copyright (c) 2001-2004 Ethan Galstad (nagios@nagios.org)\n\n");
 975         printf("This plugin tests the availability of DHCP servers on a network.\n\n");
 976
 977         print_usage();
 978
 979         printf
 980                 ("\nOptions:\n"
 981                  " -s, --serverip=IPADDRESS\n"
 982                  "   IP address of DHCP server that we must hear from\n"
 983                  " -r, --requestedip=IPADDRESS\n"
 984                  "   IP address that should be offered by at least one DHCP server\n"
 985                  " -t, --timeout=INTEGER\n"
 986                  "   Seconds to wait for DHCPOFFER before timeout occurs\n"
 987                  " -i, --interface=STRING\n"
 988                  "   Interface to to use for listening (i.e. eth0)\n"
 989                  " -v, --verbose\n"
 990                  "   Print extra information (command-line use only)\n"
 991                  " -h, --help\n"
 992                  "   Print detailed help screen\n"
 993                  " -V, --version\n"
 994                  "   Print version information\n\n"
 995                  );
 996
 997         /*support();*/
 998
 999         return;
1000         }
1001
1002
1003 /* prints usage information */
1004 void print_usage(void){
1005
1006         printf("Usage: %s [-s serverip] [-r requestedip] [-t timeout] [-i interface]\n",progname);
1007         printf("       %s --help\n",progname);
1008         printf("       %s --version\n",progname);
1009
1010         return;
1011         }
1012
1013
1014
1015
1016 /* process command-line arguments */
1017 int process_arguments(int argc, char **argv){
1018         int c;
1019
1020         if(argc<1)
1021                 return ERROR;
1022
1023         c=0;
1024         while((c+=(call_getopt(argc-c,&argv[c])))<argc){
1025
1026                 /*
1027                 if(is_option(argv[c]))
1028                         continue;
1029                 */
1030                 }
1031
1032         return validate_arguments();
1033         }
1034
1035
1036
1037 int call_getopt(int argc, char **argv){
1038         int c=0;
1039         int i=0;
1040         struct in_addr ipaddress;
1041
1042 #ifdef HAVE_GETOPT_H
1043         int option_index = 0;
1044         static struct option long_options[] =
1045         {
1046                 {"serverip",       required_argument,0,'s'},
1047                 {"requestedip",    required_argument,0,'r'},
1048                 {"timeout",        required_argument,0,'t'},
1049                 {"interface",      required_argument,0,'i'},
1050                 {"verbose",        no_argument,      0,'v'},
1051                 {"version",        no_argument,      0,'V'},
1052                 {"help",           no_argument,      0,'h'},
1053                 {0,0,0,0}
1054         };
1055 #endif
1056
1057         while(1){
1058 #ifdef HAVE_GETOPT_H
1059                 c=getopt_long(argc,argv,"+hVvt:s:r:t:i:",long_options,&option_index);
1060 #else
1061                 c=getopt(argc,argv,"+?hVvt:s:r:t:i:");
1062 #endif
1063
1064                 i++;
1065
1066                 if(c==-1||c==EOF||c==1)
1067                         break;
1068
1069                 switch(c){
1070                 case 'w':
1071                 case 'r':
1072                 case 't':
1073                 case 'i':
1074                         i++;
1075                         break;
1076                 default:
1077                         break;
1078                         }
1079
1080                 switch(c){
1081
1082                 case 's': /* DHCP server address */
1083                         if(inet_aton(optarg,&ipaddress))
1084                                 add_requested_server(ipaddress);
1085                         /*
1086                         else
1087                                 usage("Invalid server IP address\n");
1088                         */
1089                         break;
1090
1091                 case 'r': /* address we are requested from DHCP servers */
1092                         if(inet_aton(optarg,&ipaddress)){
1093                                 requested_address=ipaddress;
1094                                 request_specific_address=TRUE;
1095                                 }
1096                         /*
1097                         else
1098                                 usage("Invalid requested IP address\n");
1099                         */
1100                         break;
1101
1102                 case 't': /* timeout */
1103
1104                         /*
1105                         if(is_intnonneg(optarg))
1106                         */
1107                         if(atoi(optarg)>0)
1108                                 dhcpoffer_timeout=atoi(optarg);
1109                         /*
1110                         else
1111                                 usage("Time interval must be a nonnegative integer\n");
1112                         */
1113                         break;
1114
1115                 case 'i': /* interface name */
1116
1117                         strncpy(network_interface_name,optarg,sizeof(network_interface_name)-1);
1118                         network_interface_name[sizeof(network_interface_name)-1]='\x0';
1119
1120                         break;
1121
1122                 case 'V': /* version */
1123
1124                         /*print_revision(progname,"$Revision$");*/
1125                         exit(STATE_OK);
1126
1127                 case 'h': /* help */
1128
1129                         print_help();
1130                         exit(STATE_OK);
1131
1132                 case 'v': /* verbose */
1133
1134                         verbose=1;
1135                         break;
1136
1137                 case '?': /* help */
1138
1139                         /*usage("Invalid argument\n");*/
1140                         break;
1141
1142                 default:
1143                         break;
1144                         }
1145                 }
1146
1147         return i;
1148         }
1149
1150
1151
1152 int validate_arguments(void){
1153
1154         return OK;
1155         }
1156
1157 #if defined(__sun__) || defined(__solaris__) || defined(__hpux__)
1158
1159
1160 /*
1161  * Copyright @2000, 2003 Martin Kompf, martin@kompf.de
1162  *
1163  * Nagios plugins thanks Martin for this code.
1164  */
1165
1166 /* get a message from a stream; return type of message */
1167 static int get_msg(int fd)
1168 {
1169     int flags = 0;
1170     int res, ret;
1171     ctl_area[0] = 0;
1172     dat_area[0] = 0;
1173     ret = 0;
1174     res = getmsg(fd, &ctl, &dat, &flags);
1175
1176     if(res < 0) {
1177         if(errno == EINTR) {
1178             return(GOT_INTR);
1179         } else {
1180             printf("%s\n", "get_msg FAILED.");
1181             return(GOT_ERR);
1182         }
1183     }
1184     if(ctl.len > 0) {
1185         ret |= GOT_CTRL;
1186     }
1187     if(dat.len > 0) {
1188         ret |= GOT_DATA;
1189     }
1190     return(ret);
1191 }
1192
1193 /* verify that dl_primitive in ctl_area = prim */
1194 static int check_ctrl(int prim)
1195 {
1196     dl_error_ack_t *err_ack = (dl_error_ack_t *)ctl_area;
1197     if(err_ack->dl_primitive != prim) {
1198         printf("Error: DLPI stream API failed to get MAC in check_ctrl: %s.\n", strerror(errno));
1199         exit(STATE_UNKNOWN);
1200     }
1201     return 0;
1202 }
1203
1204 /* put a control message on a stream */
1205 static int put_ctrl(int fd, int len, int pri)
1206 {
1207     ctl.len = len;
1208     if(putmsg(fd, &ctl, 0, pri) < 0) {
1209         printf("Error: DLPI stream API failed to get MAC in put_ctrl/putmsg(): %s.\n", strerror(errno));
1210         exit(STATE_UNKNOWN);
1211     }
1212     return  0;
1213 }
1214
1215 /* put a control + data message on a stream */
1216 static int put_both(int fd, int clen, int dlen, int pri)
1217 {
1218     ctl.len = clen;
1219     dat.len = dlen;
1220     if(putmsg(fd, &ctl, &dat, pri) < 0) {
1221         printf("Error: DLPI stream API failed to get MAC in put_both/putmsg().\n", strerror(errno));
1222         exit(STATE_UNKNOWN);
1223     }
1224     return  0;
1225 }
1226
1227 /* open file descriptor and attach */
1228 static int dl_open(const char *dev, int unit, int *fd)
1229 {
1230     dl_attach_req_t *attach_req = (dl_attach_req_t *)ctl_area;
1231     if((*fd = open(dev, O_RDWR)) == -1) {
1232         printf("Error: DLPI stream API failed to get MAC in dl_attach_req/open(%s..): %s.\n", dev, strerror(errno));
1233         exit(STATE_UNKNOWN);
1234     }
1235     attach_req->dl_primitive = DL_ATTACH_REQ;
1236     attach_req->dl_ppa = unit;
1237     put_ctrl(*fd, sizeof(dl_attach_req_t), 0);
1238     get_msg(*fd);
1239     return check_ctrl(DL_OK_ACK);
1240 }
1241
1242 /* send DL_BIND_REQ */
1243 static int dl_bind(int fd, int sap, u_char *addr)
1244 {
1245     dl_bind_req_t *bind_req = (dl_bind_req_t *)ctl_area;
1246     dl_bind_ack_t *bind_ack = (dl_bind_ack_t *)ctl_area;
1247     bind_req->dl_primitive = DL_BIND_REQ;
1248     bind_req->dl_sap = sap;
1249     bind_req->dl_max_conind = 1;
1250     bind_req->dl_service_mode = DL_CLDLS;
1251     bind_req->dl_conn_mgmt = 0;
1252     bind_req->dl_xidtest_flg = 0;
1253     put_ctrl(fd, sizeof(dl_bind_req_t), 0);
1254     get_msg(fd);
1255     if (GOT_ERR == check_ctrl(DL_BIND_ACK)) {
1256         printf("Error: DLPI stream API failed to get MAC in dl_bind/check_ctrl(): %s.\n", strerror(errno));
1257         exit(STATE_UNKNOWN);
1258     }
1259     bcopy((u_char *)bind_ack + bind_ack->dl_addr_offset, addr,
1260         bind_ack->dl_addr_length);
1261     return 0;
1262 }
1263
1264 /***********************************************************************
1265  * interface:
1266  * function mac_addr_dlpi - get the mac address of the interface with
1267  *                          type dev (eg lnc, hme) and unit (0, 1 ..)
1268  *
1269  * parameter: addr: an array of six bytes, has to be allocated by the caller
1270  *
1271  * return: 0 if OK, -1 if the address could not be determined
1272  *
1273  *
1274  ***********************************************************************/
1275
1276 long mac_addr_dlpi( const char *dev, int unit, u_char  *addr) {
1277
1278         int fd;
1279         u_char mac_addr[25];
1280
1281         if (GOT_ERR != dl_open(dev, unit, &fd)) {
1282                 if (GOT_ERR != dl_bind(fd, INSAP, mac_addr)) {
1283                         bcopy( mac_addr, addr, 6);
1284                         return 0;
1285                 }
1286         }
1287         close(fd);
1288         return -1;
1289 }
1290
1291 #endif
1292