1 /****************************************************************************
2 *
3 * Nagios plugins network utilities
4 *
5 * License: GPL
6 * Copyright (c) 1999 Ethan Galstad (nagios@nagios.org)
7 *
8 * Last Modified: $Date$
9 *
10 * Description:
11 *
12 * This file contains commons functions used in many of the plugins.
13 *
14 * License Information:
15 *
16 * This program is free software; you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License as published by
18 * the Free Software Foundation; either version 2 of the License, or
19 * (at your option) any later version.
20 *
21 * This program is distributed in the hope that it will be useful,
22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
24 * GNU General Public License for more details.
25 *
26 * You should have received a copy of the GNU General Public License
27 * along with this program; if not, write to the Free Software
28 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
29 *
30 ****************************************************************************/
32 #include "config.h"
33 #include "common.h"
34 #include <sys/socket.h>
35 #include <netinet/in.h>
36 #include <arpa/inet.h>
37 #include <netdb.h>
39 extern int socket_timeout;
40 RETSIGTYPE socket_timeout_alarm_handler (int);
42 int process_tcp_request2 (char *, int, char *, char *, int);
43 int process_tcp_request (char *, int, char *, char *, int);
44 int process_udp_request (char *, int, char *, char *, int);
45 int process_request (char *, int, char *, char *, char *, int);
47 int my_tcp_connect (char *, int, int *);
48 int my_udp_connect (char *, int, int *);
49 int my_connect (char *, int, int *, char *);
51 int my_inet_aton (register const char *, struct in_addr *);
53 /* handles socket timeouts */
54 void
55 socket_timeout_alarm_handler (int sig)
56 {
58 printf ("Socket timeout after %d seconds\n", socket_timeout);
60 exit (STATE_CRITICAL);
61 }
64 /* connects to a host on a specified TCP port, sends a string,
65 and gets a response */
66 int
67 process_tcp_request (char *server_address,
68 int server_port,
69 char *send_buffer, char *recv_buffer, int recv_size)
70 {
71 int result;
72 char proto[4] = "tcp";
74 result = process_request (server_address,
75 server_port,
76 proto, send_buffer, recv_buffer, recv_size);
78 return result;
79 }
82 /* connects to a host on a specified UDP port, sends a string, and gets a
83 response */
84 int
85 process_udp_request (char *server_address,
86 int server_port,
87 char *send_buffer, char *recv_buffer, int recv_size)
88 {
89 int result;
90 char proto[4] = "udp";
92 result = process_request (server_address,
93 server_port,
94 proto, send_buffer, recv_buffer, recv_size);
96 return result;
97 }
101 /* connects to a host on a specified tcp port, sends a string, and gets a
102 response. loops on select-recv until timeout or eof to get all of a
103 multi-packet answer */
104 int
105 process_tcp_request2 (char *server_address,
106 int server_port,
107 char *send_buffer, char *recv_buffer, int recv_size)
108 {
110 int result;
111 int send_result;
112 int recv_result;
113 int sd;
114 struct timeval tv;
115 fd_set readfds;
116 int recv_length = 0;
118 result = my_connect (server_address, server_port, &sd, "tcp");
119 if (result != STATE_OK)
120 return STATE_CRITICAL;
122 send_result = send (sd, send_buffer, strlen (send_buffer), 0);
123 if (send_result != strlen (send_buffer)) {
124 printf ("send() failed\n");
125 result = STATE_WARNING;
126 }
128 while (1) {
129 /* wait up to the number of seconds for socket timeout
130 minus one for data from the host */
131 tv.tv_sec = socket_timeout - 1;
132 tv.tv_usec = 0;
133 FD_ZERO (&readfds);
134 FD_SET (sd, &readfds);
135 select (sd + 1, &readfds, NULL, NULL, &tv);
137 /* make sure some data has arrived */
138 if (!FD_ISSET (sd, &readfds)) { /* it hasn't */
139 if (!recv_length) {
140 strcpy (recv_buffer, "");
141 printf ("No data was recieved from host!\n");
142 result = STATE_WARNING;
143 }
144 else { /* this one failed, but previous ones worked */
145 recv_buffer[recv_length] = 0;
146 }
147 break;
148 }
149 else { /* it has */
150 recv_result =
151 recv (sd, recv_buffer + recv_length, recv_size - recv_length - 1, 0);
152 if (recv_result == -1) { /* recv failed, bail out */
153 strcpy (recv_buffer + recv_length, "");
154 result = STATE_WARNING;
155 break;
156 }
157 else if (recv_result == 0) { /* end of file ? */
158 recv_buffer[recv_length] = 0;
159 break;
160 }
161 else { /* we got data! */
162 recv_length += recv_result;
163 if (recv_length >= recv_size - 1) { /* buffer full, we're done */
164 recv_buffer[recv_size - 1] = 0;
165 break;
166 }
167 }
168 } /* end if(!FD_ISSET(sd,&readfds)) */
169 } /* end while(1) */
171 close (sd);
172 return result;
173 }
175 /* connects to a host on a specified port, sends a string, and gets a
176 response */
177 int
178 process_request (char *server_address,
179 int server_port,
180 char *proto,
181 char *send_buffer, char *recv_buffer, int recv_size)
182 {
183 int result;
184 int send_result;
185 int recv_result;
186 int sd;
187 struct timeval tv;
188 fd_set readfds;
190 result = STATE_OK;
192 result = my_connect (server_address, server_port, &sd, proto);
193 if (result != STATE_OK)
194 return STATE_CRITICAL;
196 send_result = send (sd, send_buffer, strlen (send_buffer), 0);
197 if (send_result != strlen (send_buffer)) {
198 printf ("send() failed\n");
199 result = STATE_WARNING;
200 }
202 /* wait up to the number of seconds for socket timeout minus one
203 for data from the host */
204 tv.tv_sec = socket_timeout - 1;
205 tv.tv_usec = 0;
206 FD_ZERO (&readfds);
207 FD_SET (sd, &readfds);
208 select (sd + 1, &readfds, NULL, NULL, &tv);
210 /* make sure some data has arrived */
211 if (!FD_ISSET (sd, &readfds)) {
212 strcpy (recv_buffer, "");
213 printf ("No data was recieved from host!\n");
214 result = STATE_WARNING;
215 }
217 else {
218 recv_result = recv (sd, recv_buffer, recv_size - 1, 0);
219 if (recv_result == -1) {
220 strcpy (recv_buffer, "");
221 if (!strcmp (proto, "tcp"))
222 printf ("recv() failed\n");
223 result = STATE_WARNING;
224 }
225 else
226 recv_buffer[recv_result] = 0;
228 /* terminate returned string */
229 recv_buffer[recv_size - 1] = 0;
230 }
232 close (sd);
234 return result;
235 }
238 /* opens a connection to a remote host/tcp port */
239 int
240 my_tcp_connect (char *host_name, int port, int *sd)
241 {
242 int result;
243 char proto[4] = "tcp";
245 result = my_connect (host_name, port, sd, proto);
247 return result;
248 }
251 /* opens a connection to a remote host/udp port */
252 int
253 my_udp_connect (char *host_name, int port, int *sd)
254 {
255 int result;
256 char proto[4] = "udp";
258 result = my_connect (host_name, port, sd, proto);
260 return result;
261 }
264 /* opens a tcp or udp connection to a remote host */
265 int
266 my_connect (char *host_name, int port, int *sd, char *proto)
267 {
268 struct sockaddr_in servaddr;
269 struct hostent *hp;
270 struct protoent *ptrp;
271 int result;
273 bzero ((char *) &servaddr, sizeof (servaddr));
274 servaddr.sin_family = AF_INET;
275 servaddr.sin_port = htons (port);
277 /* try to bypass using a DNS lookup if this is just an IP address */
278 if (!my_inet_aton (host_name, &servaddr.sin_addr)) {
280 /* else do a DNS lookup */
281 hp = gethostbyname ((const char *) host_name);
282 if (hp == NULL) {
283 printf ("Invalid host name '%s'\n", host_name);
284 return STATE_UNKNOWN;
285 }
287 memcpy (&servaddr.sin_addr, hp->h_addr, hp->h_length);
288 }
290 /* map transport protocol name to protocol number */
291 if ((ptrp = getprotobyname (proto)) == NULL) {
292 printf ("Cannot map \"%s\" to protocol number\n", proto);
293 return STATE_UNKNOWN;
294 }
296 /* create a socket */
297 *sd =
298 socket (PF_INET, (!strcmp (proto, "udp")) ? SOCK_DGRAM : SOCK_STREAM,
299 ptrp->p_proto);
300 if (*sd < 0) {
301 printf ("Socket creation failed\n");
302 return STATE_UNKNOWN;
303 }
305 /* open a connection */
306 result = connect (*sd, (struct sockaddr *) &servaddr, sizeof (servaddr));
307 if (result < 0) {
308 switch (errno) {
309 case ECONNREFUSED:
310 printf ("Connection refused by host\n");
311 break;
312 case ETIMEDOUT:
313 printf ("Timeout while attempting connection\n");
314 break;
315 case ENETUNREACH:
316 printf ("Network is unreachable\n");
317 break;
318 default:
319 printf ("Connection refused or timed out\n");
320 }
322 return STATE_CRITICAL;
323 }
325 return STATE_OK;
326 }
330 /* This code was taken from Fyodor's nmap utility, which was originally
331 taken from the GLIBC 2.0.6 libraries because Solaris doesn't contain
332 the inet_aton() funtion. */
333 int
334 my_inet_aton (register const char *cp, struct in_addr *addr)
335 {
336 register unsigned int val; /* changed from u_long --david */
337 register int base, n;
338 register char c;
339 u_int parts[4];
340 register u_int *pp = parts;
342 c = *cp;
344 for (;;) {
346 /*
347 * Collect number up to ``.''.
348 * Values are specified as for C:
349 * 0x=hex, 0=octal, isdigit=decimal.
350 */
351 if (!isdigit ((int) c))
352 return (0);
353 val = 0;
354 base = 10;
356 if (c == '0') {
357 c = *++cp;
358 if (c == 'x' || c == 'X')
359 base = 16, c = *++cp;
360 else
361 base = 8;
362 }
364 for (;;) {
365 if (isascii ((int) c) && isdigit ((int) c)) {
366 val = (val * base) + (c - '0');
367 c = *++cp;
368 }
369 else if (base == 16 && isascii ((int) c) && isxdigit ((int) c)) {
370 val = (val << 4) | (c + 10 - (islower ((int) c) ? 'a' : 'A'));
371 c = *++cp;
372 }
373 else
374 break;
375 }
377 if (c == '.') {
379 /*
380 * Internet format:
381 * a.b.c.d
382 * a.b.c (with c treated as 16 bits)
383 * a.b (with b treated as 24 bits)
384 */
385 if (pp >= parts + 3)
386 return (0);
387 *pp++ = val;
388 c = *++cp;
389 }
390 else
391 break;
392 }
394 /* Check for trailing characters */
395 if (c != '\0' && (!isascii ((int) c) || !isspace ((int) c)))
396 return (0);
398 /* Concoct the address according to the number of parts specified */
399 n = pp - parts + 1;
400 switch (n) {
402 case 0:
403 return (0); /* initial nondigit */
405 case 1: /* a -- 32 bits */
406 break;
408 case 2: /* a.b -- 8.24 bits */
409 if (val > 0xffffff)
410 return (0);
411 val |= parts[0] << 24;
412 break;
414 case 3: /* a.b.c -- 8.8.16 bits */
415 if (val > 0xffff)
416 return (0);
417 val |= (parts[0] << 24) | (parts[1] << 16);
418 break;
420 case 4: /* a.b.c.d -- 8.8.8.8 bits */
421 if (val > 0xff)
422 return (0);
423 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
424 break;
425 }
427 if (addr)
428 addr->s_addr = htonl (val);
430 return (1);
431 }