xref: /openbsd/usr.sbin/nsd/nsd-control.c (revision 6f40fd34)
1 /*
2  * nsd-control.c - remote control utility for nsd.
3  *
4  * Copyright (c) 2011, NLnet Labs. All rights reserved.
5  *
6  * This software is open source.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * Redistributions of source code must retain the above copyright notice,
13  * this list of conditions and the following disclaimer.
14  *
15  * Redistributions in binary form must reproduce the above copyright notice,
16  * this list of conditions and the following disclaimer in the documentation
17  * and/or other materials provided with the distribution.
18  *
19  * Neither the name of the NLNET LABS nor the names of its contributors may
20  * be used to endorse or promote products derived from this software without
21  * specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
27  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 /**
37  * \file
38  *
39  * The remote control utility contacts the nsd server over ssl and
40  * sends the command, receives the answer, and displays the result
41  * from the commandline.
42  */
43 
44 #include "config.h"
45 #ifdef HAVE_SSL
46 
47 #include <sys/types.h>
48 #include <unistd.h>
49 #include <string.h>
50 #ifdef HAVE_OPENSSL_SSL_H
51 #include <openssl/ssl.h>
52 #endif
53 #ifdef HAVE_OPENSSL_ERR_H
54 #include <openssl/err.h>
55 #endif
56 #ifdef HAVE_OPENSSL_RAND_H
57 #include <openssl/rand.h>
58 #endif
59 #include "util.h"
60 #include "tsig.h"
61 #include "options.h"
62 
63 /** Give nsd-control usage, and exit (1). */
64 static void
65 usage()
66 {
67 	printf("Usage:	nsd-control [options] command\n");
68 	printf("	Remote control utility for nsd server.\n");
69 	printf("Version %s. Report bugs to <%s>.\n",
70 		PACKAGE_VERSION, PACKAGE_BUGREPORT);
71 	printf("Options:\n");
72 	printf("  -c file	config file, default is %s\n", CONFIGFILE);
73 	printf("  -s ip[@port]	server address, if omitted config is used.\n");
74 	printf("  -h		show this usage help.\n");
75 	printf("Commands:\n");
76 	printf("  start				start server; runs nsd(8)\n");
77 	printf("  stop				stops the server\n");
78 	printf("  reload [<zone>]		reload modified zonefiles from disk\n");
79 	printf("  reconfig			reload the config file\n");
80 	printf("  repattern			the same as reconfig\n");
81 	printf("  log_reopen			reopen logfile (for log rotate)\n");
82 	printf("  status			display status of server\n");
83 	printf("  stats				print statistics\n");
84 	printf("  stats_noreset			peek at statistics\n");
85 	printf("  addzone <name> <pattern>	add a new zone\n");
86 	printf("  delzone <name>		remove a zone\n");
87 	printf("  addzones			add zone list on stdin {name space pattern newline}\n");
88 	printf("  delzones			remove zone list on stdin {name newline}\n");
89 	printf("  write [<zone>]		write changed zonefiles to disk\n");
90 	printf("  notify [<zone>]		send NOTIFY messages to slave servers\n");
91 	printf("  transfer [<zone>]		try to update slave zones to newer serial\n");
92 	printf("  force_transfer [<zone>]	update slave zones with AXFR, no serial check\n");
93 	printf("  zonestatus [<zone>]		print state, serial, activity\n");
94 	printf("  serverpid			get pid of server process\n");
95 	printf("  verbosity <number>		change logging detail\n");
96 	exit(1);
97 }
98 
99 /** exit with ssl error */
100 static void ssl_err(const char* s)
101 {
102 	fprintf(stderr, "error: %s\n", s);
103 	ERR_print_errors_fp(stderr);
104 	exit(1);
105 }
106 
107 /** setup SSL context */
108 static SSL_CTX*
109 setup_ctx(struct nsd_options* cfg)
110 {
111 	char* s_cert, *c_key, *c_cert;
112 	SSL_CTX* ctx;
113 
114 	s_cert = cfg->server_cert_file;
115 	c_key = cfg->control_key_file;
116 	c_cert = cfg->control_cert_file;
117 
118 	/* filenames may be relative to zonesdir */
119 	if (cfg->zonesdir && cfg->zonesdir[0] &&
120 		(s_cert[0] != '/' || c_key[0] != '/' || c_cert[0] != '/')) {
121 		if(chdir(cfg->zonesdir))
122 			ssl_err("could not chdir to zonesdir");
123 	}
124 
125         ctx = SSL_CTX_new(SSLv23_client_method());
126 	if(!ctx)
127 		ssl_err("could not allocate SSL_CTX pointer");
128         if((SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2) & SSL_OP_NO_SSLv2)
129 		!= SSL_OP_NO_SSLv2)
130 		ssl_err("could not set SSL_OP_NO_SSLv2");
131         if((SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv3) & SSL_OP_NO_SSLv3)
132 		!= SSL_OP_NO_SSLv3)
133 		ssl_err("could not set SSL_OP_NO_SSLv3");
134 	if(!SSL_CTX_use_certificate_file(ctx,c_cert,SSL_FILETYPE_PEM) ||
135 		!SSL_CTX_use_PrivateKey_file(ctx,c_key,SSL_FILETYPE_PEM)
136 		|| !SSL_CTX_check_private_key(ctx))
137 		ssl_err("Error setting up SSL_CTX client key and cert");
138 	if (SSL_CTX_load_verify_locations(ctx, s_cert, NULL) != 1)
139 		ssl_err("Error setting up SSL_CTX verify, server cert");
140 	SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, NULL);
141 
142 	return ctx;
143 }
144 
145 /** contact the server with TCP connect */
146 static int
147 contact_server(const char* svr, struct nsd_options* cfg, int statuscmd)
148 {
149 #ifdef INET6
150 	struct sockaddr_storage addr;
151 #else
152 	struct sockaddr_in addr;
153 #endif
154 	socklen_t addrlen;
155 	int fd;
156 	int port = cfg->control_port;
157 	/* use svr or a config entry */
158 	if(!svr) {
159 		if(cfg->control_interface) {
160 			svr = cfg->control_interface->address;
161 		} else if(cfg->do_ip4) {
162 			svr = "127.0.0.1";
163 		} else {
164 			svr = "::1";
165 		}
166 		/* config 0 addr (everything), means ask localhost */
167 		if(strcmp(svr, "0.0.0.0") == 0)
168 			svr = "127.0.0.1";
169 		else if(strcmp(svr, "::0") == 0 ||
170 			strcmp(svr, "0::0") == 0 ||
171 			strcmp(svr, "0::") == 0 ||
172 			strcmp(svr, "::") == 0)
173 			svr = "::1";
174 	}
175 	if(strchr(svr, '@')) {
176 		char* ps = strchr(svr, '@');
177 		*ps++ = 0;
178 		port = atoi(ps);
179 		if(!port) {
180 			fprintf(stderr, "could not parse port %s\n", ps);
181 			exit(1);
182 		}
183 	}
184         if(strchr(svr, ':')) {
185 		struct sockaddr_in6 sa;
186 		addrlen = (socklen_t)sizeof(struct sockaddr_in6);
187 		memset(&sa, 0, addrlen);
188 		sa.sin6_family = AF_INET6;
189 		sa.sin6_port = (in_port_t)htons((uint16_t)port);
190 		if(inet_pton((int)sa.sin6_family, svr, &sa.sin6_addr) <= 0) {
191 			fprintf(stderr, "could not parse IP: %s\n", svr);
192 			exit(1);
193 		}
194 		memcpy(&addr, &sa, addrlen);
195 	} else { /* ip4 */
196 		struct sockaddr_in sa;
197 		addrlen = (socklen_t)sizeof(struct sockaddr_in);
198 		memset(&sa, 0, addrlen);
199 		sa.sin_family = AF_INET;
200 		sa.sin_port = (in_port_t)htons((uint16_t)port);
201 		if(inet_pton((int)sa.sin_family, svr, &sa.sin_addr) <= 0) {
202 			fprintf(stderr, "could not parse IP: %s\n", svr);
203 			exit(1);
204 		}
205 		memcpy(&addr, &sa, addrlen);
206 	}
207 
208 	fd = socket(strchr(svr, ':')?AF_INET6:AF_INET, SOCK_STREAM, 0);
209 	if(fd == -1) {
210 		fprintf(stderr, "socket: %s\n", strerror(errno));
211 		exit(1);
212 	}
213 	if(connect(fd, (struct sockaddr*)&addr, addrlen) < 0) {
214 		fprintf(stderr, "error: connect (%s@%d): %s\n", svr, port,
215 			strerror(errno));
216 		if(errno == ECONNREFUSED && statuscmd) {
217 			printf("nsd is stopped\n");
218 			exit(3);
219 		}
220 		exit(1);
221 	}
222 	return fd;
223 }
224 
225 /** setup SSL on the connection */
226 static SSL*
227 setup_ssl(SSL_CTX* ctx, int fd)
228 {
229 	SSL* ssl;
230 	X509* x;
231 	int r;
232 
233 	ssl = SSL_new(ctx);
234 	if(!ssl)
235 		ssl_err("could not SSL_new");
236 	SSL_set_connect_state(ssl);
237 	(void)SSL_set_mode(ssl, SSL_MODE_AUTO_RETRY);
238 	if(!SSL_set_fd(ssl, fd))
239 		ssl_err("could not SSL_set_fd");
240 	while(1) {
241 		ERR_clear_error();
242 		if( (r=SSL_do_handshake(ssl)) == 1)
243 			break;
244 		r = SSL_get_error(ssl, r);
245 		if(r != SSL_ERROR_WANT_READ && r != SSL_ERROR_WANT_WRITE)
246 			ssl_err("SSL handshake failed");
247 		/* wants to be called again */
248 	}
249 
250 	/* check authenticity of server */
251 	if(SSL_get_verify_result(ssl) != X509_V_OK)
252 		ssl_err("SSL verification failed");
253 	x = SSL_get_peer_certificate(ssl);
254 	if(!x)
255 		ssl_err("Server presented no peer certificate");
256 	X509_free(x);
257 	return ssl;
258 }
259 
260 /** send stdin to server */
261 static void
262 send_file(SSL* ssl, FILE* in, char* buf, size_t sz)
263 {
264 	char e[] = {0x04, 0x0a};
265 	while(fgets(buf, (int)sz, in)) {
266 		if(SSL_write(ssl, buf, (int)strlen(buf)) <= 0)
267 			ssl_err("could not SSL_write contents");
268 	}
269 	/* send end-of-file marker */
270 	if(SSL_write(ssl, e, (int)sizeof(e)) <= 0)
271 		ssl_err("could not SSL_write end-of-file marker");
272 }
273 
274 /** send command and display result */
275 static int
276 go_cmd(SSL* ssl, int argc, char* argv[])
277 {
278 	char pre[10];
279 	const char* space=" ";
280 	const char* newline="\n";
281 	int was_error = 0, first_line = 1;
282 	int r, i;
283 	char buf[1024];
284 	snprintf(pre, sizeof(pre), "NSDCT%d ", NSD_CONTROL_VERSION);
285 	if(SSL_write(ssl, pre, (int)strlen(pre)) <= 0)
286 		ssl_err("could not SSL_write");
287 	for(i=0; i<argc; i++) {
288 		if(SSL_write(ssl, space, (int)strlen(space)) <= 0)
289 			ssl_err("could not SSL_write");
290 		if(SSL_write(ssl, argv[i], (int)strlen(argv[i])) <= 0)
291 			ssl_err("could not SSL_write");
292 	}
293 	if(SSL_write(ssl, newline, (int)strlen(newline)) <= 0)
294 		ssl_err("could not SSL_write");
295 
296 	/* send contents to server */
297 	if(argc == 1 && (strcmp(argv[0], "addzones") == 0 ||
298 		strcmp(argv[0], "delzones") == 0)) {
299 		send_file(ssl, stdin, buf, sizeof(buf));
300 	}
301 
302 	while(1) {
303 		ERR_clear_error();
304 		if((r = SSL_read(ssl, buf, (int)sizeof(buf)-1)) <= 0) {
305 			if(SSL_get_error(ssl, r) == SSL_ERROR_ZERO_RETURN) {
306 				/* EOF */
307 				break;
308 			}
309 			ssl_err("could not SSL_read");
310 		}
311 		buf[r] = 0;
312 		printf("%s", buf);
313 		if(first_line && strncmp(buf, "error", 5) == 0)
314 			was_error = 1;
315 		first_line = 0;
316 	}
317 	return was_error;
318 }
319 
320 /** go ahead and read config, contact server and perform command and display */
321 static int
322 go(const char* cfgfile, char* svr, int argc, char* argv[])
323 {
324 	struct nsd_options* opt;
325 	int fd, ret;
326 	SSL_CTX* ctx;
327 	SSL* ssl;
328 
329 	/* read config */
330 	if(!(opt = nsd_options_create(region_create(xalloc, free)))) {
331 		fprintf(stderr, "out of memory\n");
332 		exit(1);
333 	}
334 	tsig_init(opt->region);
335 	if(!parse_options_file(opt, cfgfile, NULL, NULL)) {
336 		fprintf(stderr, "could not read config file\n");
337 		exit(1);
338 	}
339 	if(!opt->control_enable)
340 		fprintf(stderr, "warning: control-enable is 'no' in the config file.\n");
341 	ctx = setup_ctx(opt);
342 
343 	/* contact server */
344 	fd = contact_server(svr, opt, argc>0&&strcmp(argv[0],"status")==0);
345 	ssl = setup_ssl(ctx, fd);
346 
347 	/* send command */
348 	ret = go_cmd(ssl, argc, argv);
349 
350 	SSL_free(ssl);
351 	close(fd);
352 	SSL_CTX_free(ctx);
353 	region_destroy(opt->region);
354 	return ret;
355 }
356 
357 /** getopt global, in case header files fail to declare it. */
358 extern int optind;
359 /** getopt global, in case header files fail to declare it. */
360 extern char* optarg;
361 
362 /** Main routine for nsd-control */
363 int main(int argc, char* argv[])
364 {
365 	int c;
366 	const char* cfgfile = CONFIGFILE;
367 	char* svr = NULL;
368 #ifdef USE_WINSOCK
369 	int r;
370 	WSADATA wsa_data;
371 #endif
372 	log_init("nsd-control");
373 
374 #ifdef HAVE_ERR_LOAD_CRYPTO_STRINGS
375 	ERR_load_crypto_strings();
376 #endif
377 	ERR_load_SSL_strings();
378 #if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_CRYPTO)
379 	OpenSSL_add_all_algorithms();
380 #else
381 	OPENSSL_init_crypto(OPENSSL_INIT_ADD_ALL_CIPHERS
382 		| OPENSSL_INIT_ADD_ALL_DIGESTS
383 		| OPENSSL_INIT_LOAD_CRYPTO_STRINGS, NULL);
384 #endif
385 #if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_SSL)
386 	(void)SSL_library_init();
387 #else
388 	OPENSSL_init_ssl(0, NULL);
389 #endif
390 
391 	if(!RAND_status()) {
392                 /* try to seed it */
393                 unsigned char buf[256];
394                 unsigned int v, seed=(unsigned)time(NULL) ^ (unsigned)getpid();
395                 size_t i;
396 		v = seed;
397                 for(i=0; i<256/sizeof(v); i++) {
398                         memmove(buf+i*sizeof(v), &v, sizeof(v));
399                         v = v*seed + (unsigned int)i;
400                 }
401                 RAND_seed(buf, 256);
402 		fprintf(stderr, "warning: no entropy, seeding openssl PRNG with time\n");
403 	}
404 
405 	/* parse the options */
406 	while( (c=getopt(argc, argv, "c:s:h")) != -1) {
407 		switch(c) {
408 		case 'c':
409 			cfgfile = optarg;
410 			break;
411 		case 's':
412 			svr = optarg;
413 			break;
414 		case '?':
415 		case 'h':
416 		default:
417 			usage();
418 		}
419 	}
420 	argc -= optind;
421 	argv += optind;
422 	if(argc == 0)
423 		usage();
424 	if(argc >= 1 && strcmp(argv[0], "start")==0) {
425 		if(execl(NSD_START_PATH, "nsd", "-c", cfgfile,
426 			(char*)NULL) < 0) {
427 			fprintf(stderr, "could not exec %s: %s\n",
428 				NSD_START_PATH, strerror(errno));
429 			exit(1);
430 		}
431 	}
432 
433 	return go(cfgfile, svr, argc, argv);
434 }
435 
436 #else /* HAVE_SSL */
437 int main(void)
438 {
439 	printf("error: NSD was compiled without SSL.\n");
440 	return 1;
441 }
442 #endif /* HAVE_SSL */
443