xref: /openbsd-src/usr.sbin/nsd/nsd-control.c (revision 50b7afb2c2c0993b0894d4e34bf857cb13ed9c80)
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("  write [<zone>]		write changed zonefiles to disk\n");
88 	printf("  notify [<zone>]		send NOTIFY messages to slave servers\n");
89 	printf("  transfer [<zone>]		try to update slave zones to newer serial\n");
90 	printf("  force_transfer [<zone>]	update slave zones with AXFR, no serial check\n");
91 	printf("  zonestatus [<zone>]		print state, serial, activity\n");
92 	printf("  serverpid			get pid of server process\n");
93 	printf("  verbosity <number>		change logging detail\n");
94 	exit(1);
95 }
96 
97 /** exit with ssl error */
98 static void ssl_err(const char* s)
99 {
100 	fprintf(stderr, "error: %s\n", s);
101 	ERR_print_errors_fp(stderr);
102 	exit(1);
103 }
104 
105 /** setup SSL context */
106 static SSL_CTX*
107 setup_ctx(nsd_options_t* cfg)
108 {
109 	char* s_cert, *c_key, *c_cert;
110 	SSL_CTX* ctx;
111 
112 	s_cert = cfg->server_cert_file;
113 	c_key = cfg->control_key_file;
114 	c_cert = cfg->control_cert_file;
115 
116 	/* filenames may be relative to zonesdir */
117 	if (cfg->zonesdir && cfg->zonesdir[0] &&
118 		(s_cert[0] != '/' || c_key[0] != '/' || c_cert[0] != '/')) {
119 		if(chdir(cfg->zonesdir))
120 			ssl_err("could not chdir to zonesdir");
121 	}
122 
123         ctx = SSL_CTX_new(SSLv23_client_method());
124 	if(!ctx)
125 		ssl_err("could not allocate SSL_CTX pointer");
126         if(!(SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2) & SSL_OP_NO_SSLv2))
127 		ssl_err("could not set SSL_OP_NO_SSLv2");
128 	if(!SSL_CTX_use_certificate_file(ctx,c_cert,SSL_FILETYPE_PEM) ||
129 		!SSL_CTX_use_PrivateKey_file(ctx,c_key,SSL_FILETYPE_PEM)
130 		|| !SSL_CTX_check_private_key(ctx))
131 		ssl_err("Error setting up SSL_CTX client key and cert");
132 	if (SSL_CTX_load_verify_locations(ctx, s_cert, NULL) != 1)
133 		ssl_err("Error setting up SSL_CTX verify, server cert");
134 	SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, NULL);
135 
136 	return ctx;
137 }
138 
139 /** contact the server with TCP connect */
140 static int
141 contact_server(const char* svr, nsd_options_t* cfg, int statuscmd)
142 {
143 #ifdef INET6
144 	struct sockaddr_storage addr;
145 #else
146 	struct sockaddr_in addr;
147 #endif
148 	socklen_t addrlen;
149 	int fd;
150 	int port = cfg->control_port;
151 	/* use svr or a config entry */
152 	if(!svr) {
153 		if(cfg->control_interface)
154 			svr = cfg->control_interface->address;
155 		else	svr = "127.0.0.1";
156 		/* config 0 addr (everything), means ask localhost */
157 		if(strcmp(svr, "0.0.0.0") == 0)
158 			svr = "127.0.0.1";
159 		else if(strcmp(svr, "::0") == 0 ||
160 			strcmp(svr, "0::0") == 0 ||
161 			strcmp(svr, "0::") == 0 ||
162 			strcmp(svr, "::") == 0)
163 			svr = "::1";
164 	}
165 	if(strchr(svr, '@')) {
166 		char* ps = strchr(svr, '@');
167 		*ps++ = 0;
168 		port = atoi(ps);
169 		if(!port) {
170 			fprintf(stderr, "could not parse port %s\n", ps);
171 			exit(1);
172 		}
173 	}
174         if(strchr(svr, ':')) {
175 		struct sockaddr_in6 sa;
176 		addrlen = (socklen_t)sizeof(struct sockaddr_in6);
177 		memset(&sa, 0, addrlen);
178 		sa.sin6_family = AF_INET6;
179 		sa.sin6_port = (in_port_t)htons((uint16_t)port);
180 		if(inet_pton((int)sa.sin6_family, svr, &sa.sin6_addr) <= 0) {
181 			fprintf(stderr, "could not parse IP: %s\n", svr);
182 			exit(1);
183 		}
184 		memcpy(&addr, &sa, addrlen);
185 	} else { /* ip4 */
186 		struct sockaddr_in sa;
187 		addrlen = (socklen_t)sizeof(struct sockaddr_in);
188 		memset(&sa, 0, addrlen);
189 		sa.sin_family = AF_INET;
190 		sa.sin_port = (in_port_t)htons((uint16_t)port);
191 		if(inet_pton((int)sa.sin_family, svr, &sa.sin_addr) <= 0) {
192 			fprintf(stderr, "could not parse IP: %s\n", svr);
193 			exit(1);
194 		}
195 		memcpy(&addr, &sa, addrlen);
196 	}
197 
198 	fd = socket(strchr(svr, ':')?AF_INET6:AF_INET, SOCK_STREAM, 0);
199 	if(fd == -1) {
200 		fprintf(stderr, "socket: %s\n", strerror(errno));
201 		exit(1);
202 	}
203 	if(connect(fd, (struct sockaddr*)&addr, addrlen) < 0) {
204 		fprintf(stderr, "error: connect (%s@%d): %s\n", svr, port,
205 			strerror(errno));
206 		if(errno == ECONNREFUSED && statuscmd) {
207 			printf("nsd is stopped\n");
208 			exit(3);
209 		}
210 		exit(1);
211 	}
212 	return fd;
213 }
214 
215 /** setup SSL on the connection */
216 static SSL*
217 setup_ssl(SSL_CTX* ctx, int fd)
218 {
219 	SSL* ssl;
220 	X509* x;
221 	int r;
222 
223 	ssl = SSL_new(ctx);
224 	if(!ssl)
225 		ssl_err("could not SSL_new");
226 	SSL_set_connect_state(ssl);
227 	(void)SSL_set_mode(ssl, SSL_MODE_AUTO_RETRY);
228 	if(!SSL_set_fd(ssl, fd))
229 		ssl_err("could not SSL_set_fd");
230 	while(1) {
231 		ERR_clear_error();
232 		if( (r=SSL_do_handshake(ssl)) == 1)
233 			break;
234 		r = SSL_get_error(ssl, r);
235 		if(r != SSL_ERROR_WANT_READ && r != SSL_ERROR_WANT_WRITE)
236 			ssl_err("SSL handshake failed");
237 		/* wants to be called again */
238 	}
239 
240 	/* check authenticity of server */
241 	if(SSL_get_verify_result(ssl) != X509_V_OK)
242 		ssl_err("SSL verification failed");
243 	x = SSL_get_peer_certificate(ssl);
244 	if(!x)
245 		ssl_err("Server presented no peer certificate");
246 	X509_free(x);
247 	return ssl;
248 }
249 
250 /** send stdin to server */
251 static void
252 send_file(SSL* ssl, FILE* in, char* buf, size_t sz)
253 {
254 	while(fgets(buf, (int)sz, in)) {
255 		if(SSL_write(ssl, buf, (int)strlen(buf)) <= 0)
256 			ssl_err("could not SSL_write contents");
257 	}
258 }
259 
260 /** send command and display result */
261 static int
262 go_cmd(SSL* ssl, int argc, char* argv[])
263 {
264 	char pre[10];
265 	const char* space=" ";
266 	const char* newline="\n";
267 	int was_error = 0, first_line = 1;
268 	int r, i;
269 	char buf[1024];
270 	snprintf(pre, sizeof(pre), "NSDCT%d ", NSD_CONTROL_VERSION);
271 	if(SSL_write(ssl, pre, (int)strlen(pre)) <= 0)
272 		ssl_err("could not SSL_write");
273 	for(i=0; i<argc; i++) {
274 		if(SSL_write(ssl, space, (int)strlen(space)) <= 0)
275 			ssl_err("could not SSL_write");
276 		if(SSL_write(ssl, argv[i], (int)strlen(argv[i])) <= 0)
277 			ssl_err("could not SSL_write");
278 	}
279 	if(SSL_write(ssl, newline, (int)strlen(newline)) <= 0)
280 		ssl_err("could not SSL_write");
281 
282 	/* TODO remove or use file upload */
283 	if(argc == 1 && strcmp(argv[0], "load_cache") == 0) {
284 		send_file(ssl, stdin, buf, sizeof(buf));
285 	}
286 
287 	while(1) {
288 		ERR_clear_error();
289 		if((r = SSL_read(ssl, buf, (int)sizeof(buf)-1)) <= 0) {
290 			if(SSL_get_error(ssl, r) == SSL_ERROR_ZERO_RETURN) {
291 				/* EOF */
292 				break;
293 			}
294 			ssl_err("could not SSL_read");
295 		}
296 		buf[r] = 0;
297 		printf("%s", buf);
298 		if(first_line && strncmp(buf, "error", 5) == 0)
299 			was_error = 1;
300 		first_line = 0;
301 	}
302 	return was_error;
303 }
304 
305 /** go ahead and read config, contact server and perform command and display */
306 static int
307 go(const char* cfgfile, char* svr, int argc, char* argv[])
308 {
309 	nsd_options_t* opt;
310 	int fd, ret;
311 	SSL_CTX* ctx;
312 	SSL* ssl;
313 
314 	/* read config */
315 	if(!(opt = nsd_options_create(region_create(xalloc, free)))) {
316 		fprintf(stderr, "out of memory\n");
317 		exit(1);
318 	}
319 	tsig_init(opt->region);
320 	if(!parse_options_file(opt, cfgfile, NULL, NULL)) {
321 		fprintf(stderr, "could not read config file\n");
322 		exit(1);
323 	}
324 	if(!opt->control_enable)
325 		fprintf(stderr, "warning: control-enable is 'no' in the config file.\n");
326 	ctx = setup_ctx(opt);
327 
328 	/* contact server */
329 	fd = contact_server(svr, opt, argc>0&&strcmp(argv[0],"status")==0);
330 	ssl = setup_ssl(ctx, fd);
331 
332 	/* send command */
333 	ret = go_cmd(ssl, argc, argv);
334 
335 	SSL_free(ssl);
336 	close(fd);
337 	SSL_CTX_free(ctx);
338 	region_destroy(opt->region);
339 	return ret;
340 }
341 
342 /** getopt global, in case header files fail to declare it. */
343 extern int optind;
344 /** getopt global, in case header files fail to declare it. */
345 extern char* optarg;
346 
347 /** Main routine for nsd-control */
348 int main(int argc, char* argv[])
349 {
350 	int c;
351 	const char* cfgfile = CONFIGFILE;
352 	char* svr = NULL;
353 #ifdef USE_WINSOCK
354 	int r;
355 	WSADATA wsa_data;
356 #endif
357 	log_init("nsd-control");
358 
359 	ERR_load_crypto_strings();
360 	ERR_load_SSL_strings();
361 	OpenSSL_add_all_algorithms();
362 	(void)SSL_library_init();
363 
364 	if(!RAND_status()) {
365                 /* try to seed it */
366                 unsigned char buf[256];
367                 unsigned int v, seed=(unsigned)time(NULL) ^ (unsigned)getpid();
368                 size_t i;
369 		v = seed;
370                 for(i=0; i<256/sizeof(v); i++) {
371                         memmove(buf+i*sizeof(v), &v, sizeof(v));
372                         v = v*seed + (unsigned int)i;
373                 }
374                 RAND_seed(buf, 256);
375 		fprintf(stderr, "warning: no entropy, seeding openssl PRNG with time\n");
376 	}
377 
378 	/* parse the options */
379 	while( (c=getopt(argc, argv, "c:s:h")) != -1) {
380 		switch(c) {
381 		case 'c':
382 			cfgfile = optarg;
383 			break;
384 		case 's':
385 			svr = optarg;
386 			break;
387 		case '?':
388 		case 'h':
389 		default:
390 			usage();
391 		}
392 	}
393 	argc -= optind;
394 	argv += optind;
395 	if(argc == 0)
396 		usage();
397 	if(argc >= 1 && strcmp(argv[0], "start")==0) {
398 		if(execl(NSD_START_PATH, "nsd", "-c", cfgfile,
399 			(char*)NULL) < 0) {
400 			fprintf(stderr, "could not exec %s: %s\n",
401 				NSD_START_PATH, strerror(errno));
402 			exit(1);
403 		}
404 	}
405 
406 	return go(cfgfile, svr, argc, argv);
407 }
408 
409 #else /* HAVE_SSL */
410 int main(void)
411 {
412 	printf("error: NSD was compiled without SSL.\n");
413 	return 1;
414 }
415 #endif /* HAVE_SSL */
416