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Diffstat (limited to 'contrib/check_dhcp.c')
-rw-r--r-- | contrib/check_dhcp.c | 1001 |
1 files changed, 0 insertions, 1001 deletions
diff --git a/contrib/check_dhcp.c b/contrib/check_dhcp.c deleted file mode 100644 index 8669e44..0000000 --- a/contrib/check_dhcp.c +++ /dev/null | |||
@@ -1,1001 +0,0 @@ | |||
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 <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 received\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 | address_size=sizeof(source_address); | ||
484 | recv_result=recvfrom(sock,(char *)buffer,buffer_size,MSG_PEEK,(struct sockaddr *)&source_address,&address_size); | ||
485 | #ifdef DEBUG | ||
486 | printf("recv_result_1: %d\n",recv_result); | ||
487 | #endif | ||
488 | recv_result=recvfrom(sock,(char *)buffer,buffer_size,0,(struct sockaddr *)&source_address,&address_size); | ||
489 | #ifdef DEBUG | ||
490 | printf("recv_result_2: %d\n",recv_result); | ||
491 | #endif | ||
492 | |||
493 | if(recv_result==-1){ | ||
494 | #ifdef DEBUG | ||
495 | printf("recvfrom() failed, "); | ||
496 | printf("errno: (%d) -> %s\n",errno,strerror(errno)); | ||
497 | #endif | ||
498 | return ERROR; | ||
499 | } | ||
500 | else{ | ||
501 | #ifdef DEBUG | ||
502 | printf("receive_dhcp_packet() result: %d\n",recv_result); | ||
503 | printf("receive_dhcp_packet() source: %s\n",inet_ntoa(source_address.sin_addr)); | ||
504 | #endif | ||
505 | |||
506 | memcpy(address,&source_address,sizeof(source_address)); | ||
507 | return OK; | ||
508 | } | ||
509 | } | ||
510 | |||
511 | return OK; | ||
512 | } | ||
513 | |||
514 | |||
515 | |||
516 | /* creates a socket for DHCP communication */ | ||
517 | int create_dhcp_socket(void){ | ||
518 | struct sockaddr_in myname; | ||
519 | struct ifreq interface; | ||
520 | int sock; | ||
521 | int flag=1; | ||
522 | |||
523 | /* Set up the address we're going to bind to. */ | ||
524 | bzero(&myname,sizeof(myname)); | ||
525 | myname.sin_family=AF_INET; | ||
526 | myname.sin_port=htons(DHCP_CLIENT_PORT); | ||
527 | myname.sin_addr.s_addr=INADDR_ANY; /* listen on any address */ | ||
528 | bzero(&myname.sin_zero,sizeof(myname.sin_zero)); | ||
529 | |||
530 | /* create a socket for DHCP communications */ | ||
531 | sock=socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP); | ||
532 | if(sock<0){ | ||
533 | printf("Error: Could not create socket!\n"); | ||
534 | exit(STATE_UNKNOWN); | ||
535 | } | ||
536 | |||
537 | #ifdef DEBUG | ||
538 | printf("DHCP socket: %d\n",sock); | ||
539 | #endif | ||
540 | |||
541 | /* set the reuse address flag so we don't get errors when restarting */ | ||
542 | flag=1; | ||
543 | if(setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,(char *)&flag,sizeof(flag))<0){ | ||
544 | printf("Error: Could not set reuse address option on DHCP socket!\n"); | ||
545 | exit(STATE_UNKNOWN); | ||
546 | } | ||
547 | |||
548 | /* set the broadcast option - we need this to listen to DHCP broadcast messages */ | ||
549 | if(setsockopt(sock,SOL_SOCKET,SO_BROADCAST,(char *)&flag,sizeof flag)<0){ | ||
550 | printf("Error: Could not set broadcast option on DHCP socket!\n"); | ||
551 | exit(STATE_UNKNOWN); | ||
552 | } | ||
553 | |||
554 | /* bind socket to interface */ | ||
555 | strncpy(interface.ifr_ifrn.ifrn_name,network_interface_name,IFNAMSIZ); | ||
556 | if(setsockopt(sock,SOL_SOCKET,SO_BINDTODEVICE,(char *)&interface,sizeof(interface))<0){ | ||
557 | printf("Error: Could not bind socket to interface %s. Check your privileges...\n",network_interface_name); | ||
558 | exit(STATE_UNKNOWN); | ||
559 | } | ||
560 | |||
561 | /* bind the socket */ | ||
562 | if(bind(sock,(struct sockaddr *)&myname,sizeof(myname))<0){ | ||
563 | printf("Error: Could not bind to DHCP socket (port %d)! Check your privileges...\n",DHCP_CLIENT_PORT); | ||
564 | exit(STATE_UNKNOWN); | ||
565 | } | ||
566 | |||
567 | return sock; | ||
568 | } | ||
569 | |||
570 | |||
571 | |||
572 | |||
573 | |||
574 | /* closes DHCP socket */ | ||
575 | int close_dhcp_socket(int sock){ | ||
576 | |||
577 | close(sock); | ||
578 | |||
579 | return OK; | ||
580 | } | ||
581 | |||
582 | |||
583 | |||
584 | |||
585 | /* adds a requested server address to list in memory */ | ||
586 | int add_requested_server(struct in_addr server_address){ | ||
587 | requested_server *new_server; | ||
588 | |||
589 | new_server=(requested_server *)malloc(sizeof(requested_server)); | ||
590 | if(new_server==NULL) | ||
591 | return ERROR; | ||
592 | |||
593 | new_server->server_address=server_address; | ||
594 | |||
595 | new_server->next=requested_server_list; | ||
596 | requested_server_list=new_server; | ||
597 | |||
598 | requested_servers++; | ||
599 | |||
600 | #ifdef DEBUG | ||
601 | printf("Requested server address: %s\n",inet_ntoa(new_server->server_address)); | ||
602 | #endif | ||
603 | |||
604 | return OK; | ||
605 | } | ||
606 | |||
607 | |||
608 | |||
609 | |||
610 | /* adds a DHCP OFFER to list in memory */ | ||
611 | int add_dhcp_offer(struct in_addr source,dhcp_packet *offer_packet){ | ||
612 | dhcp_offer *new_offer; | ||
613 | int x; | ||
614 | int y; | ||
615 | unsigned option_type; | ||
616 | unsigned option_length; | ||
617 | |||
618 | if(offer_packet==NULL) | ||
619 | return ERROR; | ||
620 | |||
621 | /* process all DHCP options present in the packet */ | ||
622 | for(x=4;x<MAX_DHCP_OPTIONS_LENGTH;){ | ||
623 | |||
624 | /* end of options (0 is really just a pad, but bail out anyway) */ | ||
625 | if((int)offer_packet->options[x]==-1 || (int)offer_packet->options[x]==0) | ||
626 | break; | ||
627 | |||
628 | /* get option type */ | ||
629 | option_type=offer_packet->options[x++]; | ||
630 | |||
631 | /* get option length */ | ||
632 | option_length=offer_packet->options[x++]; | ||
633 | |||
634 | #ifdef DEBUG | ||
635 | printf("Option: %d (0x%02X)\n",option_type,option_length); | ||
636 | #endif | ||
637 | |||
638 | /* get option data */ | ||
639 | if(option_type==DHCP_OPTION_LEASE_TIME) | ||
640 | dhcp_lease_time=ntohl(*((u_int32_t *)&offer_packet->options[x])); | ||
641 | if(option_type==DHCP_OPTION_RENEWAL_TIME) | ||
642 | dhcp_renewal_time=ntohl(*((u_int32_t *)&offer_packet->options[x])); | ||
643 | if(option_type==DHCP_OPTION_REBINDING_TIME) | ||
644 | dhcp_rebinding_time=ntohl(*((u_int32_t *)&offer_packet->options[x])); | ||
645 | |||
646 | /* skip option data we're ignoring */ | ||
647 | else | ||
648 | for(y=0;y<option_length;y++,x++); | ||
649 | } | ||
650 | |||
651 | #ifdef DEBUG | ||
652 | if(dhcp_lease_time==DHCP_INFINITE_TIME) | ||
653 | printf("Lease Time: Infinite\n"); | ||
654 | else | ||
655 | printf("Lease Time: %lu seconds\n",(unsigned long)dhcp_lease_time); | ||
656 | if(dhcp_renewal_time==DHCP_INFINITE_TIME) | ||
657 | printf("Renewal Time: Infinite\n"); | ||
658 | else | ||
659 | printf("Renewal Time: %lu seconds\n",(unsigned long)dhcp_renewal_time); | ||
660 | if(dhcp_rebinding_time==DHCP_INFINITE_TIME) | ||
661 | printf("Rebinding Time: Infinite\n"); | ||
662 | printf("Rebinding Time: %lu seconds\n",(unsigned long)dhcp_rebinding_time); | ||
663 | #endif | ||
664 | |||
665 | new_offer=(dhcp_offer *)malloc(sizeof(dhcp_offer)); | ||
666 | |||
667 | if(new_offer==NULL) | ||
668 | return ERROR; | ||
669 | |||
670 | |||
671 | new_offer->server_address=source; | ||
672 | new_offer->offered_address=offer_packet->yiaddr; | ||
673 | new_offer->lease_time=dhcp_lease_time; | ||
674 | new_offer->renewal_time=dhcp_renewal_time; | ||
675 | new_offer->rebinding_time=dhcp_rebinding_time; | ||
676 | |||
677 | |||
678 | #ifdef DEBUG | ||
679 | printf("Added offer from server @ %s",inet_ntoa(new_offer->server_address)); | ||
680 | printf(" of IP address %s\n",inet_ntoa(new_offer->offered_address)); | ||
681 | #endif | ||
682 | |||
683 | /* add new offer to head of list */ | ||
684 | new_offer->next=dhcp_offer_list; | ||
685 | dhcp_offer_list=new_offer; | ||
686 | |||
687 | return OK; | ||
688 | } | ||
689 | |||
690 | |||
691 | |||
692 | |||
693 | /* frees memory allocated to DHCP OFFER list */ | ||
694 | int free_dhcp_offer_list(void){ | ||
695 | dhcp_offer *this_offer; | ||
696 | dhcp_offer *next_offer; | ||
697 | |||
698 | for(this_offer=dhcp_offer_list;this_offer!=NULL;this_offer=next_offer){ | ||
699 | next_offer=this_offer->next; | ||
700 | free(this_offer); | ||
701 | } | ||
702 | |||
703 | return OK; | ||
704 | } | ||
705 | |||
706 | |||
707 | |||
708 | |||
709 | /* frees memory allocated to requested server list */ | ||
710 | int free_requested_server_list(void){ | ||
711 | requested_server *this_server; | ||
712 | requested_server *next_server; | ||
713 | |||
714 | for(this_server=requested_server_list;this_server!=NULL;this_server=next_server){ | ||
715 | next_server=this_server->next; | ||
716 | free(this_server); | ||
717 | } | ||
718 | |||
719 | return OK; | ||
720 | } | ||
721 | |||
722 | |||
723 | /* gets state and plugin output to return */ | ||
724 | int get_results(void){ | ||
725 | dhcp_offer *temp_offer; | ||
726 | requested_server *temp_server; | ||
727 | int result; | ||
728 | u_int32_t max_lease_time=0; | ||
729 | |||
730 | received_requested_address=FALSE; | ||
731 | |||
732 | /* checks responses from requested servers */ | ||
733 | requested_responses=0; | ||
734 | if(requested_servers>0){ | ||
735 | |||
736 | for(temp_server=requested_server_list;temp_server!=NULL;temp_server=temp_server->next){ | ||
737 | |||
738 | for(temp_offer=dhcp_offer_list;temp_offer!=NULL;temp_offer=temp_offer->next){ | ||
739 | |||
740 | /* get max lease time we were offered */ | ||
741 | if(temp_offer->lease_time>max_lease_time || temp_offer->lease_time==DHCP_INFINITE_TIME) | ||
742 | max_lease_time=temp_offer->lease_time; | ||
743 | |||
744 | /* see if we got the address we requested */ | ||
745 | if(!memcmp(&requested_address,&temp_offer->offered_address,sizeof(requested_address))) | ||
746 | received_requested_address=TRUE; | ||
747 | |||
748 | /* see if the servers we wanted a response from talked to us or not */ | ||
749 | if(!memcmp(&temp_offer->server_address,&temp_server->server_address,sizeof(temp_server->server_address))){ | ||
750 | #ifdef DEBUG | ||
751 | printf("DHCP Server Match: Offerer=%s",inet_ntoa(temp_offer->server_address)); | ||
752 | printf(" Requested=%s\n",inet_ntoa(temp_server->server_address)); | ||
753 | #endif | ||
754 | requested_responses++; | ||
755 | } | ||
756 | } | ||
757 | } | ||
758 | |||
759 | } | ||
760 | |||
761 | /* else check and see if we got our requested address from any server */ | ||
762 | else{ | ||
763 | |||
764 | for(temp_offer=dhcp_offer_list;temp_offer!=NULL;temp_offer=temp_offer->next){ | ||
765 | |||
766 | /* get max lease time we were offered */ | ||
767 | if(temp_offer->lease_time>max_lease_time || temp_offer->lease_time==DHCP_INFINITE_TIME) | ||
768 | max_lease_time=temp_offer->lease_time; | ||
769 | |||
770 | /* see if we got the address we requested */ | ||
771 | if(!memcmp(&requested_address,&temp_offer->offered_address,sizeof(requested_address))) | ||
772 | received_requested_address=TRUE; | ||
773 | } | ||
774 | } | ||
775 | |||
776 | result=STATE_OK; | ||
777 | if(valid_responses==0) | ||
778 | result=STATE_CRITICAL; | ||
779 | else if(requested_servers>0 && requested_responses==0) | ||
780 | result=STATE_CRITICAL; | ||
781 | else if(requested_responses<requested_servers) | ||
782 | result=STATE_WARNING; | ||
783 | else if(request_specific_address==TRUE && received_requested_address==FALSE) | ||
784 | result=STATE_WARNING; | ||
785 | |||
786 | |||
787 | printf("DHCP %s: ",(result==STATE_OK)?"ok":"problem"); | ||
788 | |||
789 | /* we didn't receive any DHCPOFFERs */ | ||
790 | if(dhcp_offer_list==NULL){ | ||
791 | printf("No DHCPOFFERs were received.\n"); | ||
792 | return result; | ||
793 | } | ||
794 | |||
795 | printf("Received %d DHCPOFFER(s)",valid_responses); | ||
796 | |||
797 | if(requested_servers>0) | ||
798 | printf(", %s%d of %d requested servers responded",((requested_responses<requested_servers) && requested_responses>0)?"only ":"",requested_responses,requested_servers); | ||
799 | |||
800 | if(request_specific_address==TRUE) | ||
801 | printf(", requested address (%s) was %soffered",inet_ntoa(requested_address),(received_requested_address==TRUE)?"":"not "); | ||
802 | |||
803 | printf(", max lease time = "); | ||
804 | if(max_lease_time==DHCP_INFINITE_TIME) | ||
805 | printf("Infinity"); | ||
806 | else | ||
807 | printf("%lu sec",(unsigned long)max_lease_time); | ||
808 | |||
809 | printf(".\n"); | ||
810 | |||
811 | return result; | ||
812 | } | ||
813 | |||
814 | |||
815 | |||
816 | |||
817 | |||
818 | |||
819 | /* print usage help */ | ||
820 | void print_help(void){ | ||
821 | |||
822 | /*print_revision(progname,"$Revision$");*/ | ||
823 | |||
824 | printf("Copyright (c) 2001-2004 Ethan Galstad (nagios@nagios.org)\n\n"); | ||
825 | printf("This plugin tests the availability of DHCP servers on a network.\n\n"); | ||
826 | |||
827 | print_usage(); | ||
828 | |||
829 | printf | ||
830 | ("\nOptions:\n" | ||
831 | " -s, --serverip=IPADDRESS\n" | ||
832 | " IP address of DHCP server that we must hear from\n" | ||
833 | " -r, --requestedip=IPADDRESS\n" | ||
834 | " IP address that should be offered by at least one DHCP server\n" | ||
835 | " -t, --timeout=INTEGER\n" | ||
836 | " Seconds to wait for DHCPOFFER before timeout occurs\n" | ||
837 | " -i, --interface=STRING\n" | ||
838 | " Interface to to use for listening (i.e. eth0)\n" | ||
839 | " -v, --verbose\n" | ||
840 | " Print extra information (command-line use only)\n" | ||
841 | " -h, --help\n" | ||
842 | " Print detailed help screen\n" | ||
843 | " -V, --version\n" | ||
844 | " Print version information\n\n" | ||
845 | ); | ||
846 | |||
847 | /*support();*/ | ||
848 | |||
849 | return; | ||
850 | } | ||
851 | |||
852 | |||
853 | /* prints usage information */ | ||
854 | void print_usage(void){ | ||
855 | |||
856 | printf("Usage: %s [-s serverip] [-r requestedip] [-t timeout] [-i interface]\n",progname); | ||
857 | printf(" %s --help\n",progname); | ||
858 | printf(" %s --version\n",progname); | ||
859 | |||
860 | return; | ||
861 | } | ||
862 | |||
863 | |||
864 | |||
865 | |||
866 | /* process command-line arguments */ | ||
867 | int process_arguments(int argc, char **argv){ | ||
868 | int c; | ||
869 | |||
870 | if(argc<1) | ||
871 | return ERROR; | ||
872 | |||
873 | c=0; | ||
874 | while((c+=(call_getopt(argc-c,&argv[c])))<argc){ | ||
875 | |||
876 | /* | ||
877 | if(is_option(argv[c])) | ||
878 | continue; | ||
879 | */ | ||
880 | } | ||
881 | |||
882 | return validate_arguments(); | ||
883 | } | ||
884 | |||
885 | |||
886 | |||
887 | int call_getopt(int argc, char **argv){ | ||
888 | int c=0; | ||
889 | int i=0; | ||
890 | struct in_addr ipaddress; | ||
891 | |||
892 | #ifdef HAVE_GETOPT_H | ||
893 | int option_index = 0; | ||
894 | static struct option long_options[] = | ||
895 | { | ||
896 | {"serverip", required_argument,0,'s'}, | ||
897 | {"requestedip", required_argument,0,'r'}, | ||
898 | {"timeout", required_argument,0,'t'}, | ||
899 | {"interface", required_argument,0,'i'}, | ||
900 | {"verbose", no_argument, 0,'v'}, | ||
901 | {"version", no_argument, 0,'V'}, | ||
902 | {"help", no_argument, 0,'h'}, | ||
903 | {0,0,0,0} | ||
904 | }; | ||
905 | #endif | ||
906 | |||
907 | while(1){ | ||
908 | #ifdef HAVE_GETOPT_H | ||
909 | c=getopt_long(argc,argv,"+hVvt:s:r:t:i:",long_options,&option_index); | ||
910 | #else | ||
911 | c=getopt(argc,argv,"+?hVvt:s:r:t:i:"); | ||
912 | #endif | ||
913 | |||
914 | i++; | ||
915 | |||
916 | if(c==-1||c==EOF||c==1) | ||
917 | break; | ||
918 | |||
919 | switch(c){ | ||
920 | case 'w': | ||
921 | case 'r': | ||
922 | case 't': | ||
923 | case 'i': | ||
924 | i++; | ||
925 | break; | ||
926 | default: | ||
927 | break; | ||
928 | } | ||
929 | |||
930 | switch(c){ | ||
931 | |||
932 | case 's': /* DHCP server address */ | ||
933 | if(inet_aton(optarg,&ipaddress)) | ||
934 | add_requested_server(ipaddress); | ||
935 | /* | ||
936 | else | ||
937 | usage("Invalid server IP address\n"); | ||
938 | */ | ||
939 | break; | ||
940 | |||
941 | case 'r': /* address we are requested from DHCP servers */ | ||
942 | if(inet_aton(optarg,&ipaddress)){ | ||
943 | requested_address=ipaddress; | ||
944 | request_specific_address=TRUE; | ||
945 | } | ||
946 | /* | ||
947 | else | ||
948 | usage("Invalid requested IP address\n"); | ||
949 | */ | ||
950 | break; | ||
951 | |||
952 | case 't': /* timeout */ | ||
953 | |||
954 | /* | ||
955 | if(is_intnonneg(optarg)) | ||
956 | */ | ||
957 | if(atoi(optarg)>0) | ||
958 | dhcpoffer_timeout=atoi(optarg); | ||
959 | /* | ||
960 | else | ||
961 | usage("Time interval must be a nonnegative integer\n"); | ||
962 | */ | ||
963 | break; | ||
964 | |||
965 | case 'i': /* interface name */ | ||
966 | |||
967 | strncpy(network_interface_name,optarg,sizeof(network_interface_name)-1); | ||
968 | network_interface_name[sizeof(network_interface_name)-1]='\x0'; | ||
969 | |||
970 | break; | ||
971 | |||
972 | case 'V': /* version */ | ||
973 | |||
974 | /*print_revision(progname,"$Revision$");*/ | ||
975 | exit(STATE_OK); | ||
976 | |||
977 | case 'h': /* help */ | ||
978 | |||
979 | print_help(); | ||
980 | exit(STATE_OK); | ||
981 | |||
982 | case '?': /* help */ | ||
983 | |||
984 | /*usage("Invalid argument\n");*/ | ||
985 | break; | ||
986 | |||
987 | default: | ||
988 | break; | ||
989 | } | ||
990 | } | ||
991 | |||
992 | return i; | ||
993 | } | ||
994 | |||
995 | |||
996 | |||
997 | int validate_arguments(void){ | ||
998 | |||
999 | return OK; | ||
1000 | } | ||
1001 | |||