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- Committer: Bazaar Package Importer
- Author(s): Guido Trotter
- Date: 2004-06-15 15:37:48 UTC
- Revision ID: james.westby@ubuntu.com-20040615153748-pq7702qdzghqfcns
Tags: upstream-1.3.1.0
Import upstream version 1.3.1.0
- files added:
- contrib
- contrib/aix
- contrib/tarballs
- lib
- plugins
- plugins-scripts
- plugins-scripts/t
- plugins/t
added
removed
contrib/check_dhcp.c
1
/******************************************************************************
2
*
3
* CHECK_DHCP.C
4
*
5
* Program: DHCP plugin for Nagios
6
* License: GPL
7
* Copyright (c) 2001-2002 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 <stdio.h>
28
#include <stdlib.h>
29
#include <string.h>
30
#include <errno.h>
31
#include <unistd.h>
32
#include <sys/time.h>
33
#include <sys/ioctl.h>
34
#include <fcntl.h>
35
#include <features.h>
36
#include <linux/if_ether.h>
37
#include <getopt.h>
38
#include <net/if.h>
39
#include <sys/socket.h>
40
#include <sys/types.h>
41
#include <netinet/in.h>
42
#include <arpa/inet.h>
43
#include <netdb.h>
44
45
const char *progname = "check_dhcp";
46
47
/*#define DEBUG*/
48
#define HAVE_GETOPT_H
49
50
51
/**** Common definitions ****/
52
53
#define STATE_OK 0
54
#define STATE_WARNING 1
55
#define STATE_CRITICAL 2
56
#define STATE_UNKNOWN -1
57
58
#define OK 0
59
#define ERROR -1
60
61
#define FALSE 0
62
#define TRUE 1
63
64
65
/**** DHCP definitions ****/
66
67
#define MAX_DHCP_CHADDR_LENGTH 16
68
#define MAX_DHCP_SNAME_LENGTH 64
69
#define MAX_DHCP_FILE_LENGTH 128
70
#define MAX_DHCP_OPTIONS_LENGTH 312
71
72
73
typedef struct dhcp_packet_struct{
74
u_int8_t op; /* packet type */
75
u_int8_t htype; /* type of hardware address for this machine (Ethernet, etc) */
76
u_int8_t hlen; /* length of hardware address (of this machine) */
77
u_int8_t hops; /* hops */
78
u_int32_t xid; /* random transaction id number - chosen by this machine */
79
u_int16_t secs; /* seconds used in timing */
80
u_int16_t flags; /* flags */
81
struct in_addr ciaddr; /* IP address of this machine (if we already have one) */
82
struct in_addr yiaddr; /* IP address of this machine (offered by the DHCP server) */
83
struct in_addr siaddr; /* IP address of DHCP server */
84
struct in_addr giaddr; /* IP address of DHCP relay */
85
unsigned char chaddr [MAX_DHCP_CHADDR_LENGTH]; /* hardware address of this machine */
86
char sname [MAX_DHCP_SNAME_LENGTH]; /* name of DHCP server */
87
char file [MAX_DHCP_FILE_LENGTH]; /* boot file name (used for diskless booting?) */
88
char options[MAX_DHCP_OPTIONS_LENGTH]; /* options */
89
}dhcp_packet;
90
91
92
typedef struct dhcp_offer_struct{
93
struct in_addr server_address; /* address of DHCP server that sent this offer */
94
struct in_addr offered_address; /* the IP address that was offered to us */
95
u_int32_t lease_time; /* lease time in seconds */
96
u_int32_t renewal_time; /* renewal time in seconds */
97
u_int32_t rebinding_time; /* rebinding time in seconds */
98
struct dhcp_offer_struct *next;
99
}dhcp_offer;
100
101
102
typedef struct requested_server_struct{
103
struct in_addr server_address;
104
struct requested_server_struct *next;
105
}requested_server;
106
107
108
#define BOOTREQUEST 1
109
#define BOOTREPLY 2
110
111
#define DHCPDISCOVER 1
112
#define DHCPOFFER 2
113
#define DHCPREQUEST 3
114
#define DHCPDECLINE 4
115
#define DHCPACK 5
116
#define DHCPNACK 6
117
#define DHCPRELEASE 7
118
119
#define DHCP_OPTION_MESSAGE_TYPE 53
120
#define DHCP_OPTION_HOST_NAME 12
121
#define DHCP_OPTION_BROADCAST_ADDRESS 28
122
#define DHCP_OPTION_REQUESTED_ADDRESS 50
123
#define DHCP_OPTION_LEASE_TIME 51
124
#define DHCP_OPTION_RENEWAL_TIME 58
125
#define DHCP_OPTION_REBINDING_TIME 59
126
127
#define DHCP_INFINITE_TIME 0xFFFFFFFF
128
129
#define DHCP_BROADCAST_FLAG 32768
130
131
#define DHCP_SERVER_PORT 67
132
#define DHCP_CLIENT_PORT 68
133
134
#define ETHERNET_HARDWARE_ADDRESS 1 /* used in htype field of dhcp packet */
135
#define ETHERNET_HARDWARE_ADDRESS_LENGTH 6 /* length of Ethernet hardware addresses */
136
137
unsigned char client_hardware_address[MAX_DHCP_CHADDR_LENGTH]="";
138
139
char network_interface_name[8]="eth0";
140
141
u_int32_t packet_xid=0;
142
143
u_int32_t dhcp_lease_time=0;
144
u_int32_t dhcp_renewal_time=0;
145
u_int32_t dhcp_rebinding_time=0;
146
147
int dhcpoffer_timeout=2;
148
149
dhcp_offer *dhcp_offer_list=NULL;
150
requested_server *requested_server_list=NULL;
151
152
int valid_responses=0; /* number of valid DHCPOFFERs we received */
153
int requested_servers=0;
154
int requested_responses=0;
155
156
int request_specific_address=FALSE;
157
int received_requested_address=FALSE;
158
struct in_addr requested_address;
159
160
161
int process_arguments(int, char **);
162
int call_getopt(int, char **);
163
int validate_arguments(void);
164
void print_usage(void);
165
void print_help(void);
166
167
int get_hardware_address(int,char *);
168
169
int send_dhcp_discover(int);
170
int get_dhcp_offer(int);
171
172
int get_results(void);
173
174
int add_dhcp_offer(struct in_addr,dhcp_packet *);
175
int free_dhcp_offer_list(void);
176
int free_requested_server_list(void);
177
178
int create_dhcp_socket(void);
179
int close_dhcp_socket(int);
180
int send_dhcp_packet(void *,int,int,struct sockaddr_in *);
181
int receive_dhcp_packet(void *,int,int,int,struct sockaddr_in *);
182
183
184
185
int main(int argc, char **argv){
186
int dhcp_socket;
187
int result;
188
189
if(process_arguments(argc,argv)!=OK){
190
/*usage("Invalid command arguments supplied\n");*/
191
printf("Invalid command arguments supplied\n");
192
exit(STATE_UNKNOWN);
193
}
194
195
196
/* create socket for DHCP communications */
197
dhcp_socket=create_dhcp_socket();
198
199
/* get hardware address of client machine */
200
get_hardware_address(dhcp_socket,network_interface_name);
201
202
/* send DHCPDISCOVER packet */
203
send_dhcp_discover(dhcp_socket);
204
205
/* wait for a DHCPOFFER packet */
206
get_dhcp_offer(dhcp_socket);
207
208
/* close socket we created */
209
close_dhcp_socket(dhcp_socket);
210
211
/* determine state/plugin output to return */
212
result=get_results();
213
214
/* free allocated memory */
215
free_dhcp_offer_list();
216
free_requested_server_list();
217
218
return result;
219
}
220
221
222
223
/* determines hardware address on client machine */
224
int get_hardware_address(int sock,char *interface_name){
225
struct ifreq ifr;
226
227
strncpy((char *)&ifr.ifr_name,interface_name,sizeof(ifr.ifr_name));
228
229
/* try and grab hardware address of requested interface */
230
if(ioctl(sock,SIOCGIFHWADDR,&ifr)<0){
231
printf("Error: Could not get hardware address of interface '%s'\n",interface_name);
232
exit(STATE_UNKNOWN);
233
}
234
235
memcpy(&client_hardware_address[0],&ifr.ifr_hwaddr.sa_data,6);
236
237
#ifdef DEBUG
238
printf("Hardware address: %02x:%02x:%02x:",client_hardware_address[0],client_hardware_address[1],client_hardware_address[2]);
239
printf("%02x:",client_hardware_address[3]);
240
printf("%02x:%02x\n",client_hardware_address[4],client_hardware_address[5]);
241
printf("\n");
242
#endif
243
244
return OK;
245
}
246
247
248
/* sends a DHCPDISCOVER broadcast message in an attempt to find DHCP servers */
249
int send_dhcp_discover(int sock){
250
dhcp_packet discover_packet;
251
struct sockaddr_in sockaddr_broadcast;
252
253
254
/* clear the packet data structure */
255
bzero(&discover_packet,sizeof(discover_packet));
256
257
258
/* boot request flag (backward compatible with BOOTP servers) */
259
discover_packet.op=BOOTREQUEST;
260
261
/* hardware address type */
262
discover_packet.htype=ETHERNET_HARDWARE_ADDRESS;
263
264
/* length of our hardware address */
265
discover_packet.hlen=ETHERNET_HARDWARE_ADDRESS_LENGTH;
266
267
discover_packet.hops=0;
268
269
/* transaction id is supposed to be random */
270
srand(time(NULL));
271
packet_xid=random();
272
discover_packet.xid=htonl(packet_xid);
273
274
/**** WHAT THE HECK IS UP WITH THIS?!? IF I DON'T MAKE THIS CALL, ONLY ONE SERVER RESPONSE IS PROCESSED!!!! ****/
275
/* downright bizzarre... */
276
ntohl(discover_packet.xid);
277
278
/*discover_packet.secs=htons(65535);*/
279
discover_packet.secs=0xFF;
280
281
/* tell server it should broadcast its response */
282
discover_packet.flags=htons(DHCP_BROADCAST_FLAG);
283
284
/* our hardware address */
285
memcpy(discover_packet.chaddr,client_hardware_address,ETHERNET_HARDWARE_ADDRESS_LENGTH);
286
287
/* first four bytes of options field is magic cookie (as per RFC 2132) */
288
discover_packet.options[0]='\x63';
289
discover_packet.options[1]='\x82';
290
discover_packet.options[2]='\x53';
291
discover_packet.options[3]='\x63';
292
293
/* DHCP message type is embedded in options field */
294
discover_packet.options[4]=DHCP_OPTION_MESSAGE_TYPE; /* DHCP message type option identifier */
295
discover_packet.options[5]='\x01'; /* DHCP message option length in bytes */
296
discover_packet.options[6]=DHCPDISCOVER;
297
298
/* the IP address we're requesting */
299
if(request_specific_address==TRUE){
300
discover_packet.options[7]=DHCP_OPTION_REQUESTED_ADDRESS;
301
discover_packet.options[8]='\x04';
302
memcpy(&discover_packet.options[9],&requested_address,sizeof(requested_address));
303
}
304
305
/* send the DHCPDISCOVER packet to broadcast address */
306
sockaddr_broadcast.sin_family=AF_INET;
307
sockaddr_broadcast.sin_port=htons(DHCP_SERVER_PORT);
308
sockaddr_broadcast.sin_addr.s_addr=INADDR_BROADCAST;
309
bzero(&sockaddr_broadcast.sin_zero,sizeof(sockaddr_broadcast.sin_zero));
310
311
312
#ifdef DEBUG
313
printf("DHCPDISCOVER to %s port %d\n",inet_ntoa(sockaddr_broadcast.sin_addr),ntohs(sockaddr_broadcast.sin_port));
314
printf("DHCPDISCOVER XID: %lu (0x%X)\n",ntohl(discover_packet.xid),ntohl(discover_packet.xid));
315
printf("DHCDISCOVER ciaddr: %s\n",inet_ntoa(discover_packet.ciaddr));
316
printf("DHCDISCOVER yiaddr: %s\n",inet_ntoa(discover_packet.yiaddr));
317
printf("DHCDISCOVER siaddr: %s\n",inet_ntoa(discover_packet.siaddr));
318
printf("DHCDISCOVER giaddr: %s\n",inet_ntoa(discover_packet.giaddr));
319
#endif
320
321
/* send the DHCPDISCOVER packet out */
322
send_dhcp_packet(&discover_packet,sizeof(discover_packet),sock,&sockaddr_broadcast);
323
324
#ifdef DEBUG
325
printf("\n\n");
326
#endif
327
328
return OK;
329
}
330
331
332
333
334
/* waits for a DHCPOFFER message from one or more DHCP servers */
335
int get_dhcp_offer(int sock){
336
dhcp_packet offer_packet;
337
struct sockaddr_in source;
338
int result=OK;
339
int timeout=1;
340
int responses=0;
341
int x;
342
time_t start_time;
343
time_t current_time;
344
345
time(&start_time);
346
347
/* receive as many responses as we can */
348
for(responses=0,valid_responses=0;;){
349
350
time(¤t_time);
351
if((current_time-start_time)>=dhcpoffer_timeout)
352
break;
353
354
#ifdef DEBUG
355
printf("\n\n");
356
#endif
357
358
bzero(&source,sizeof(source));
359
bzero(&offer_packet,sizeof(offer_packet));
360
361
result=OK;
362
result=receive_dhcp_packet(&offer_packet,sizeof(offer_packet),sock,dhcpoffer_timeout,&source);
363
364
if(result!=OK){
365
#ifdef DEBUG
366
printf("Result=ERROR\n");
367
#endif
368
continue;
369
}
370
else{
371
#ifdef DEBUG
372
printf("Result=OK\n");
373
#endif
374
responses++;
375
}
376
377
#ifdef DEBUG
378
printf("DHCPOFFER from IP address %s\n",inet_ntoa(source.sin_addr));
379
printf("DHCPOFFER XID: %lu (0x%X)\n",ntohl(offer_packet.xid),ntohl(offer_packet.xid));
380
#endif
381
382
/* check packet xid to see if its the same as the one we used in the discover packet */
383
if(ntohl(offer_packet.xid)!=packet_xid){
384
#ifdef DEBUG
385
printf("DHCPOFFER XID (%lu) did not match DHCPDISCOVER XID (%lu) - ignoring packet\n",ntohl(offer_packet.xid),packet_xid);
386
#endif
387
continue;
388
}
389
390
/* check hardware address */
391
result=OK;
392
#ifdef DEBUG
393
printf("DHCPOFFER chaddr: ");
394
#endif
395
for(x=0;x<ETHERNET_HARDWARE_ADDRESS_LENGTH;x++){
396
#ifdef DEBUG
397
printf("%02X",(unsigned char)offer_packet.chaddr[x]);
398
#endif
399
if(offer_packet.chaddr[x]!=client_hardware_address[x]){
400
result=ERROR;
401
}
402
}
403
#ifdef DEBUG
404
printf("\n");
405
#endif
406
if(result==ERROR){
407
#ifdef DEBUG
408
printf("DHCPOFFER hardware address did not match our own - ignoring packet\n");
409
#endif
410
continue;
411
}
412
413
#ifdef DEBUG
414
printf("DHCPOFFER ciaddr: %s\n",inet_ntoa(offer_packet.ciaddr));
415
printf("DHCPOFFER yiaddr: %s\n",inet_ntoa(offer_packet.yiaddr));
416
printf("DHCPOFFER siaddr: %s\n",inet_ntoa(offer_packet.siaddr));
417
printf("DHCPOFFER giaddr: %s\n",inet_ntoa(offer_packet.giaddr));
418
#endif
419
420
add_dhcp_offer(source.sin_addr,&offer_packet);
421
422
valid_responses++;
423
}
424
425
#ifdef DEBUG
426
printf("Total responses seen on the wire: %d\n",responses);
427
printf("Valid responses for this machine: %d\n",valid_responses);
428
#endif
429
430
return OK;
431
}
432
433
434
435
/* sends a DHCP packet */
436
int send_dhcp_packet(void *buffer, int buffer_size, int sock, struct sockaddr_in *dest){
437
struct sockaddr_in myname;
438
int result;
439
440
result=sendto(sock,(char *)buffer,buffer_size,0,(struct sockaddr *)dest,sizeof(*dest));
441
442
#ifdef DEBUG
443
printf("send_dhcp_packet result: %d\n",result);
444
#endif
445
446
if(result<0)
447
return ERROR;
448
449
return OK;
450
}
451
452
453
454
/* receives a DHCP packet */
455
int receive_dhcp_packet(void *buffer, int buffer_size, int sock, int timeout, struct sockaddr_in *address){
456
struct timeval tv;
457
fd_set readfds;
458
int recv_result;
459
socklen_t address_size;
460
struct sockaddr_in source_address;
461
462
463
/* wait for data to arrive (up time timeout) */
464
tv.tv_sec=timeout;
465
tv.tv_usec=0;
466
FD_ZERO(&readfds);
467
FD_SET(sock,&readfds);
468
select(sock+1,&readfds,NULL,NULL,&tv);
469
470
/* make sure some data has arrived */
471
if(!FD_ISSET(sock,&readfds)){
472
#ifdef DEBUG
473
printf("No (more) data recieved\n");
474
#endif
475
return ERROR;
476
}
477
478
else{
479
480
/* 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
481
not being interpreted correctly. sigh... */
482
bzero(&source_address,sizeof(source_address));
483
recv_result=recvfrom(sock,(char *)buffer,buffer_size,MSG_PEEK,(struct sockaddr *)&source_address,&address_size);
484
#ifdef DEBUG
485
printf("recv_result_1: %d\n",recv_result);
486
#endif
487
recv_result=recvfrom(sock,(char *)buffer,buffer_size,0,(struct sockaddr *)&source_address,&address_size);
488
#ifdef DEBUG
489
printf("recv_result_2: %d\n",recv_result);
490
#endif
491
492
if(recv_result==-1){
493
#ifdef DEBUG
494
printf("recvfrom() failed, ");
495
printf("errno: (%d) -> %s\n",errno,strerror(errno));
496
#endif
497
return ERROR;
498
}
499
else{
500
#ifdef DEBUG
501
printf("receive_dhcp_packet() result: %d\n",recv_result);
502
printf("receive_dhcp_packet() source: %s\n",inet_ntoa(source_address.sin_addr));
503
#endif
504
505
memcpy(address,&source_address,sizeof(source_address));
506
return OK;
507
}
508
}
509
510
return OK;
511
}
512
513
514
515
/* creates a socket for DHCP communication */
516
int create_dhcp_socket(void){
517
struct sockaddr_in myname;
518
struct ifreq interface;
519
int sock;
520
int flag=1;
521
522
/* Set up the address we're going to bind to. */
523
bzero(&myname,sizeof(myname));
524
myname.sin_family=AF_INET;
525
myname.sin_port=htons(DHCP_CLIENT_PORT);
526
myname.sin_addr.s_addr=INADDR_ANY; /* listen on any address */
527
bzero(&myname.sin_zero,sizeof(myname.sin_zero));
528
529
/* create a socket for DHCP communications */
530
sock=socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP);
531
if(sock<0){
532
printf("Error: Could not create socket!\n");
533
exit(STATE_UNKNOWN);
534
}
535
536
#ifdef DEBUG
537
printf("DHCP socket: %d\n",sock);
538
#endif
539
540
/* set the reuse address flag so we don't get errors when restarting */
541
flag=1;
542
if(setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,(char *)&flag,sizeof(flag))<0){
543
printf("Error: Could not set reuse address option on DHCP socket!\n");
544
exit(STATE_UNKNOWN);
545
}
546
547
/* set the broadcast option - we need this to listen to DHCP broadcast messages */
548
if(setsockopt(sock,SOL_SOCKET,SO_BROADCAST,(char *)&flag,sizeof flag)<0){
549
printf("Error: Could not set broadcast option on DHCP socket!\n");
550
exit(STATE_UNKNOWN);
551
}
552
553
/* bind socket to interface */
554
strncpy(interface.ifr_ifrn.ifrn_name,network_interface_name,IFNAMSIZ);
555
if(setsockopt(sock,SOL_SOCKET,SO_BINDTODEVICE,(char *)&interface,sizeof(interface))<0){
556
printf("Error: Could not bind socket to interface %s. Check your privileges...\n",network_interface_name);
557
exit(STATE_UNKNOWN);
558
}
559
560
/* bind the socket */
561
if(bind(sock,(struct sockaddr *)&myname,sizeof(myname))<0){
562
printf("Error: Could not bind to DHCP socket (port %d)! Check your privileges...\n",DHCP_CLIENT_PORT);
563
exit(STATE_UNKNOWN);
564
}
565
566
return sock;
567
}
568
569
570
571
572
573
/* closes DHCP socket */
574
int close_dhcp_socket(int sock){
575
576
close(sock);
577
578
return OK;
579
}
580
581
582
583
584
/* adds a requested server address to list in memory */
585
int add_requested_server(struct in_addr server_address){
586
requested_server *new_server;
587
588
new_server=(requested_server *)malloc(sizeof(requested_server));
589
if(new_server==NULL)
590
return ERROR;
591
592
new_server->server_address=server_address;
593
594
new_server->next=requested_server_list;
595
requested_server_list=new_server;
596
597
requested_servers++;
598
599
#ifdef DEBUG
600
printf("Requested server address: %s\n",inet_ntoa(new_server->server_address));
601
#endif
602
603
return OK;
604
}
605
606
607
608
609
/* adds a DHCP OFFER to list in memory */
610
int add_dhcp_offer(struct in_addr source,dhcp_packet *offer_packet){
611
dhcp_offer *new_offer;
612
int x;
613
int y;
614
unsigned option_type;
615
unsigned option_length;
616
617
if(offer_packet==NULL)
618
return ERROR;
619
620
/* process all DHCP options present in the packet */
621
for(x=4;x<MAX_DHCP_OPTIONS_LENGTH;){
622
623
/* end of options (0 is really just a pad, but bail out anyway) */
624
if((int)offer_packet->options[x]==-1 || (int)offer_packet->options[x]==0)
625
break;
626
627
/* get option type */
628
option_type=offer_packet->options[x++];
629
630
/* get option length */
631
option_length=offer_packet->options[x++];
632
633
#ifdef DEBUG
634
printf("Option: %d (0x%02X)\n",option_type,option_length);
635
#endif
636
637
/* get option data */
638
if(option_type==DHCP_OPTION_LEASE_TIME)
639
dhcp_lease_time=ntohl(*((u_int32_t *)&offer_packet->options[x]));
640
if(option_type==DHCP_OPTION_RENEWAL_TIME)
641
dhcp_renewal_time=ntohl(*((u_int32_t *)&offer_packet->options[x]));
642
if(option_type==DHCP_OPTION_REBINDING_TIME)
643
dhcp_rebinding_time=ntohl(*((u_int32_t *)&offer_packet->options[x]));
644
645
/* skip option data we're ignoring */
646
else
647
for(y=0;y<option_length;y++,x++);
648
}
649
650
#ifdef DEBUG
651
if(dhcp_lease_time==DHCP_INFINITE_TIME)
652
printf("Lease Time: Infinite\n");
653
else
654
printf("Lease Time: %lu seconds\n",(unsigned long)dhcp_lease_time);
655
if(dhcp_renewal_time==DHCP_INFINITE_TIME)
656
printf("Renewal Time: Infinite\n");
657
else
658
printf("Renewal Time: %lu seconds\n",(unsigned long)dhcp_renewal_time);
659
if(dhcp_rebinding_time==DHCP_INFINITE_TIME)
660
printf("Rebinding Time: Infinite\n");
661
printf("Rebinding Time: %lu seconds\n",(unsigned long)dhcp_rebinding_time);
662
#endif
663
664
new_offer=(dhcp_offer *)malloc(sizeof(dhcp_offer));
665
666
if(new_offer==NULL)
667
return ERROR;
668
669
670
new_offer->server_address=source;
671
new_offer->offered_address=offer_packet->yiaddr;
672
new_offer->lease_time=dhcp_lease_time;
673
new_offer->renewal_time=dhcp_renewal_time;
674
new_offer->rebinding_time=dhcp_rebinding_time;
675
676
677
#ifdef DEBUG
678
printf("Added offer from server @ %s",inet_ntoa(new_offer->server_address));
679
printf(" of IP address %s\n",inet_ntoa(new_offer->offered_address));
680
#endif
681
682
/* add new offer to head of list */
683
new_offer->next=dhcp_offer_list;
684
dhcp_offer_list=new_offer;
685
686
return OK;
687
}
688
689
690
691
692
/* frees memory allocated to DHCP OFFER list */
693
int free_dhcp_offer_list(void){
694
dhcp_offer *this_offer;
695
dhcp_offer *next_offer;
696
697
for(this_offer=dhcp_offer_list;this_offer!=NULL;this_offer=next_offer){
698
next_offer=this_offer->next;
699
free(this_offer);
700
}
701
702
return OK;
703
}
704
705
706
707
708
/* frees memory allocated to requested server list */
709
int free_requested_server_list(void){
710
requested_server *this_server;
711
requested_server *next_server;
712
713
for(this_server=requested_server_list;this_server!=NULL;this_server=next_server){
714
next_server=this_server->next;
715
free(this_server);
716
}
717
718
return OK;
719
}
720
721
722
/* gets state and plugin output to return */
723
int get_results(void){
724
dhcp_offer *temp_offer;
725
requested_server *temp_server;
726
int result;
727
u_int32_t max_lease_time=0;
728
729
received_requested_address=FALSE;
730
731
/* checks responses from requested servers */
732
requested_responses=0;
733
if(requested_servers>0){
734
735
for(temp_server=requested_server_list;temp_server!=NULL;temp_server=temp_server->next){
736
737
for(temp_offer=dhcp_offer_list;temp_offer!=NULL;temp_offer=temp_offer->next){
738
739
/* get max lease time we were offered */
740
if(temp_offer->lease_time>max_lease_time || temp_offer->lease_time==DHCP_INFINITE_TIME)
741
max_lease_time=temp_offer->lease_time;
742
743
/* see if we got the address we requested */
744
if(!memcmp(&requested_address,&temp_offer->offered_address,sizeof(requested_address)))
745
received_requested_address=TRUE;
746
747
/* see if the servers we wanted a response from talked to us or not */
748
if(!memcmp(&temp_offer->server_address,&temp_server->server_address,sizeof(temp_server->server_address))){
749
#ifdef DEBUG
750
printf("DHCP Server Match: Offerer=%s",inet_ntoa(temp_offer->server_address));
751
printf(" Requested=%s\n",inet_ntoa(temp_server->server_address));
752
#endif
753
requested_responses++;
754
}
755
}
756
}
757
758
}
759
760
/* else check and see if we got our requested address from any server */
761
else{
762
763
for(temp_offer=dhcp_offer_list;temp_offer!=NULL;temp_offer=temp_offer->next){
764
765
/* get max lease time we were offered */
766
if(temp_offer->lease_time>max_lease_time || temp_offer->lease_time==DHCP_INFINITE_TIME)
767
max_lease_time=temp_offer->lease_time;
768
769
/* see if we got the address we requested */
770
if(!memcmp(&requested_address,&temp_offer->offered_address,sizeof(requested_address)))
771
received_requested_address=TRUE;
772
}
773
}
774
775
result=STATE_OK;
776
if(valid_responses==0)
777
result=STATE_CRITICAL;
778
else if(requested_servers>0 && requested_responses==0)
779
result=STATE_CRITICAL;
780
else if(requested_responses<requested_servers)
781
result=STATE_WARNING;
782
else if(request_specific_address==TRUE && received_requested_address==FALSE)
783
result=STATE_WARNING;
784
785
786
printf("DHCP %s: ",(result==STATE_OK)?"ok":"problem");
787
788
/* we didn't receive any DHCPOFFERs */
789
if(dhcp_offer_list==NULL){
790
printf("No DHCPOFFERs were received.\n");
791
return result;
792
}
793
794
printf("Received %d DHCPOFFER(s)",valid_responses);
795
796
if(requested_servers>0)
797
printf(", %s%d of %d requested servers responded",((requested_responses<requested_servers) && requested_responses>0)?"only ":"",requested_responses,requested_servers);
798
799
if(request_specific_address==TRUE)
800
printf(", requested address (%s) was %soffered",inet_ntoa(requested_address),(received_requested_address==TRUE)?"":"not ");
801
802
printf(", max lease time = ");
803
if(max_lease_time==DHCP_INFINITE_TIME)
804
printf("Infinity");
805
else
806
printf("%lu sec",(unsigned long)max_lease_time);
807
808
printf(".\n");
809
810
return result;
811
}
812
813
814
815
816
817
818
/* print usage help */
819
void print_help(void){
820
821
/*print_revision(progname,"$Revision: 1.4 $");*/
822
823
printf("Copyright (c) 2001-2002 Ethan Galstad (nagios@nagios.org)\n\n");
824
printf("This plugin tests the availability of DHCP servers on a network.\n\n");
825
826
print_usage();
827
828
printf
829
("\nOptions:\n"
830
" -s, --serverip=IPADDRESS\n"
831
" IP address of DHCP server that we must hear from\n"
832
" -r, --requestedip=IPADDRESS\n"
833
" IP address that should be offered by at least one DHCP server\n"
834
" -t, --timeout=INTEGER\n"
835
" Seconds to wait for DHCPOFFER before timeout occurs\n"
836
" -i, --interface=STRING\n"
837
" Interface to to use for listening (i.e. eth0)\n"
838
" -v, --verbose\n"
839
" Print extra information (command-line use only)\n"
840
" -h, --help\n"
841
" Print detailed help screen\n"
842
" -V, --version\n"
843
" Print version information\n\n"
844
);
845
846
/*support();*/
847
848
return;
849
}
850
851
852
/* prints usage information */
853
void print_usage(void){
854
855
printf("Usage: %s [-s serverip] [-r requestedip] [-t timeout] [-i interface]\n",progname);
856
printf(" %s --help\n",progname);
857
printf(" %s --version\n",progname);
858
859
return;
860
}
861
862
863
864
865
/* process command-line arguments */
866
int process_arguments(int argc, char **argv){
867
int c;
868
869
if(argc<1)
870
return ERROR;
871
872
c=0;
873
while((c+=(call_getopt(argc-c,&argv[c])))<argc){
874
875
/*
876
if(is_option(argv[c]))
877
continue;
878
*/
879
}
880
881
return validate_arguments();
882
}
883
884
885
886
int call_getopt(int argc, char **argv){
887
int c=0;
888
int i=0;
889
struct in_addr ipaddress;
890
891
#ifdef HAVE_GETOPT_H
892
int option_index = 0;
893
static struct option long_options[] =
894
{
895
{"serverip", required_argument,0,'s'},
896
{"requestedip", required_argument,0,'r'},
897
{"timeout", required_argument,0,'t'},
898
{"interface", required_argument,0,'i'},
899
{"verbose", no_argument, 0,'v'},
900
{"version", no_argument, 0,'V'},
901
{"help", no_argument, 0,'h'},
902
{0,0,0,0}
903
};
904
#endif
905
906
while(1){
907
#ifdef HAVE_GETOPT_H
908
c=getopt_long(argc,argv,"+hVvt:s:r:t:i:",long_options,&option_index);
909
#else
910
c=getopt(argc,argv,"+?hVvt:s:r:t:i:");
911
#endif
912
913
i++;
914
915
if(c==-1||c==EOF||c==1)
916
break;
917
918
switch(c){
919
case 'w':
920
case 'r':
921
case 't':
922
case 'i':
923
i++;
924
break;
925
default:
926
break;
927
}
928
929
switch(c){
930
931
case 's': /* DHCP server address */
932
if(inet_aton(optarg,&ipaddress))
933
add_requested_server(ipaddress);
934
/*
935
else
936
usage("Invalid server IP address\n");
937
*/
938
break;
939
940
case 'r': /* address we are requested from DHCP servers */
941
if(inet_aton(optarg,&ipaddress)){
942
requested_address=ipaddress;
943
request_specific_address=TRUE;
944
}
945
/*
946
else
947
usage("Invalid requested IP address\n");
948
*/
949
break;
950
951
case 't': /* timeout */
952
953
/*
954
if(is_intnonneg(optarg))
955
*/
956
if(atoi(optarg)>0)
957
dhcpoffer_timeout=atoi(optarg);
958
/*
959
else
960
usage("Time interval must be a nonnegative integer\n");
961
*/
962
break;
963
964
case 'i': /* interface name */
965
966
strncpy(network_interface_name,optarg,sizeof(network_interface_name)-1);
967
network_interface_name[sizeof(network_interface_name)-1]='\x0';
968
969
break;
970
971
case 'V': /* version */
972
973
/*print_revision(progname,"$Revision: 1.4 $");*/
974
exit(STATE_OK);
975
976
case 'h': /* help */
977
978
print_help();
979
exit(STATE_OK);
980
981
case '?': /* help */
982
983
/*usage("Invalid argument\n");*/
984
break;
985
986
default:
987
break;
988
}
989
}
990
991
return i;
992
}
993
994
995
996
int validate_arguments(void){
997
998
return OK;
999
}
1000
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Version: 2.0.1