unbound-host.c revision 356345
1/*
2 * checkconf/unbound-host.c - replacement for host that supports validation.
3 *
4 * Copyright (c) 2007, 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 * This file performs functionality like 'host', and also supports validation.
40 * It uses the libunbound library.
41 */
42
43#include "config.h"
44#ifdef HAVE_GETOPT_H
45#include <getopt.h>
46#endif
47/* remove alloc checks, not in this part of the code */
48#ifdef UNBOUND_ALLOC_STATS
49#undef malloc
50#undef calloc
51#undef free
52#undef realloc
53#endif
54#ifdef UNBOUND_ALLOC_LITE
55#undef malloc
56#undef calloc
57#undef free
58#undef realloc
59#undef strdup
60#define unbound_lite_wrapstr(s) s
61#endif
62#include "libunbound/unbound.h"
63#include "sldns/rrdef.h"
64#include "sldns/wire2str.h"
65#ifdef HAVE_NSS
66/* nss3 */
67#include "nss.h"
68#endif
69#ifdef HAVE_SSL
70#ifdef HAVE_OPENSSL_SSL_H
71#include <openssl/ssl.h>
72#endif
73#ifdef HAVE_OPENSSL_ERR_H
74#include <openssl/err.h>
75#endif
76#endif /* HAVE_SSL */
77
78/** verbosity for unbound-host app */
79static int verb = 0;
80
81/** Give unbound-host usage, and exit (1). */
82static void
83usage(void)
84{
85	printf("Usage:	unbound-host [-C configfile] [-vdhr46] [-c class] [-t type]\n");
86	printf("                     [-y key] [-f keyfile] [-F namedkeyfile] hostname\n");
87	printf("  Queries the DNS for information.\n");
88	printf("  The hostname is looked up for IP4, IP6 and mail.\n");
89	printf("  If an ip-address is given a reverse lookup is done.\n");
90	printf("  Use the -v option to see DNSSEC security information.\n");
91	printf("    -t type		what type to look for.\n");
92	printf("    -c class		what class to look for, if not class IN.\n");
93	printf("    -y 'keystring'	specify trust anchor, DS or DNSKEY, like\n");
94	printf("			-y 'example.com DS 31560 5 1 1CFED8478...'\n");
95	printf("    -D			DNSSEC enable with default root anchor\n");
96	printf("    			from %s\n", ROOT_ANCHOR_FILE);
97	printf("    -f keyfile		read trust anchors from file, with lines as -y.\n");
98	printf("    -F keyfile		read named.conf-style trust anchors.\n");
99	printf("    -C config		use the specified unbound.conf (none read by default)\n");
100	printf("			pass as first argument if you want to override some\n");
101	printf("			options with further arguments\n");
102	printf("    -r			read forwarder information from /etc/resolv.conf\n");
103	printf("      			breaks validation if the forwarder does not do DNSSEC.\n");
104	printf("    -v			be more verbose, shows nodata and security.\n");
105	printf("    -d			debug, traces the action, -d -d shows more.\n");
106	printf("    -4			use ipv4 network, avoid ipv6.\n");
107	printf("    -6			use ipv6 network, avoid ipv4.\n");
108	printf("    -h			show this usage help.\n");
109	printf("Version %s\n", PACKAGE_VERSION);
110	printf("BSD licensed, see LICENSE in source package for details.\n");
111	printf("Report bugs to %s\n", PACKAGE_BUGREPORT);
112	exit(1);
113}
114
115/** determine if str is ip4 and put into reverse lookup format */
116static int
117isip4(const char* nm, char** res)
118{
119	struct in_addr addr;
120	/* ddd.ddd.ddd.ddd.in-addr.arpa. is less than 32 */
121	char buf[32];
122	if(inet_pton(AF_INET, nm, &addr) <= 0) {
123		return 0;
124	}
125	snprintf(buf, sizeof(buf), "%u.%u.%u.%u.in-addr.arpa",
126		(unsigned)((uint8_t*)&addr)[3], (unsigned)((uint8_t*)&addr)[2],
127		(unsigned)((uint8_t*)&addr)[1], (unsigned)((uint8_t*)&addr)[0]);
128	*res = strdup(buf);
129	return 1;
130}
131
132/** determine if str is ip6 and put into reverse lookup format */
133static int
134isip6(const char* nm, char** res)
135{
136	struct in6_addr addr;
137	/* [nibble.]{32}.ip6.arpa. is less than 128 */
138	const char* hex = "0123456789abcdef";
139	char buf[128];
140	char *p;
141	int i;
142	if(inet_pton(AF_INET6, nm, &addr) <= 0) {
143		return 0;
144	}
145	p = buf;
146	for(i=15; i>=0; i--) {
147		uint8_t b = ((uint8_t*)&addr)[i];
148		*p++ = hex[ (b&0x0f) ];
149		*p++ = '.';
150		*p++ = hex[ (b&0xf0) >> 4 ];
151		*p++ = '.';
152	}
153	snprintf(buf+16*4, sizeof(buf)-16*4, "ip6.arpa");
154	*res = strdup(buf);
155	if(!*res) {
156		fprintf(stderr, "error: out of memory\n");
157		exit(1);
158	}
159	return 1;
160}
161
162/** massage input name */
163static char*
164massage_qname(const char* nm, int* reverse)
165{
166	/* recognise IP4 and IP6, create reverse addresses if needed */
167	char* res;
168	if(isip4(nm, &res)) {
169		*reverse = 1;
170	} else if(isip6(nm, &res)) {
171		*reverse = 1;
172	} else {
173		res = strdup(nm);
174	}
175	if(!res) {
176		fprintf(stderr, "error: out of memory\n");
177		exit(1);
178	}
179	return res;
180}
181
182/** massage input type */
183static int
184massage_type(const char* t, int reverse, int* multi)
185{
186	if(t) {
187		int r = sldns_get_rr_type_by_name(t);
188		if(r == 0 && strcasecmp(t, "TYPE0") != 0 &&
189			strcmp(t, "") != 0) {
190			fprintf(stderr, "error unknown type %s\n", t);
191			exit(1);
192		}
193		return r;
194	}
195	if(!t && reverse)
196		return LDNS_RR_TYPE_PTR;
197	*multi = 1;
198	return LDNS_RR_TYPE_A;
199}
200
201/** massage input class */
202static int
203massage_class(const char* c)
204{
205	if(c) {
206		int r = sldns_get_rr_class_by_name(c);
207		if(r == 0 && strcasecmp(c, "CLASS0") != 0 &&
208			strcmp(c, "") != 0) {
209			fprintf(stderr, "error unknown class %s\n", c);
210			exit(1);
211		}
212		return r;
213	}
214	return LDNS_RR_CLASS_IN;
215}
216
217/** nice security status string */
218static const char*
219secure_str(struct ub_result* result)
220{
221	if(result->rcode != 0 && result->rcode != 3) return "(error)";
222	if(result->secure) return "(secure)";
223	if(result->bogus) return "(BOGUS (security failure))";
224	return "(insecure)";
225}
226
227/** nice string for type */
228static void
229pretty_type(char* s, size_t len, int t)
230{
231	char d[16];
232	sldns_wire2str_type_buf((uint16_t)t, d, sizeof(d));
233	snprintf(s, len, "%s", d);
234}
235
236/** nice string for class */
237static void
238pretty_class(char* s, size_t len, int c)
239{
240	char d[16];
241	sldns_wire2str_class_buf((uint16_t)c, d, sizeof(d));
242	snprintf(s, len, "%s", d);
243}
244
245/** nice string for rcode */
246static void
247pretty_rcode(char* s, size_t len, int r)
248{
249	char d[16];
250	sldns_wire2str_rcode_buf(r, d, sizeof(d));
251	snprintf(s, len, "%s", d);
252}
253
254/** convert and print rdata */
255static void
256print_rd(int t, char* data, size_t len)
257{
258	char s[65535];
259	sldns_wire2str_rdata_buf((uint8_t*)data, len, s, sizeof(s), (uint16_t)t);
260	printf(" %s", s);
261}
262
263/** pretty line of RR data for results */
264static void
265pretty_rdata(char* q, char* cstr, char* tstr, int t, const char* sec,
266	char* data, size_t len)
267{
268	printf("%s", q);
269	if(strcmp(cstr, "IN") != 0)
270		printf(" in class %s", cstr);
271	if(t == LDNS_RR_TYPE_A)
272		printf(" has address");
273	else if(t == LDNS_RR_TYPE_AAAA)
274		printf(" has IPv6 address");
275	else if(t == LDNS_RR_TYPE_MX)
276		printf(" mail is handled by");
277	else if(t == LDNS_RR_TYPE_PTR)
278		printf(" domain name pointer");
279	else	printf(" has %s record", tstr);
280	print_rd(t, data, len);
281	if(verb > 0)
282		printf(" %s", sec);
283	printf("\n");
284}
285
286/** pretty line of output for results */
287static void
288pretty_output(char* q, int t, int c, struct ub_result* result, int docname)
289{
290	int i;
291	const char *secstatus = secure_str(result);
292	char tstr[16];
293	char cstr[16];
294	char rcodestr[16];
295	pretty_type(tstr, 16, t);
296	pretty_class(cstr, 16, c);
297	pretty_rcode(rcodestr, 16, result->rcode);
298
299	if(!result->havedata && result->rcode) {
300		printf("Host %s not found: %d(%s).",
301			q, result->rcode, rcodestr);
302		if(verb > 0)
303			printf(" %s", secstatus);
304		printf("\n");
305		if(result->bogus && result->why_bogus)
306			printf("%s\n", result->why_bogus);
307		return;
308	}
309	if(docname && result->canonname &&
310		result->canonname != result->qname) {
311		printf("%s is an alias for %s", result->qname,
312			result->canonname);
313		if(verb > 0)
314			printf(" %s", secstatus);
315		printf("\n");
316	}
317	/* remove trailing . from long canonnames for nicer output */
318	if(result->canonname && strlen(result->canonname) > 1 &&
319		result->canonname[strlen(result->canonname)-1] == '.')
320		result->canonname[strlen(result->canonname)-1] = 0;
321	if(!result->havedata) {
322		if(verb > 0) {
323			printf("%s", result->canonname?result->canonname:q);
324			if(strcmp(cstr, "IN") != 0)
325				printf(" in class %s", cstr);
326			if(t == LDNS_RR_TYPE_A)
327				printf(" has no address");
328			else if(t == LDNS_RR_TYPE_AAAA)
329				printf(" has no IPv6 address");
330			else if(t == LDNS_RR_TYPE_PTR)
331				printf(" has no domain name ptr");
332			else if(t == LDNS_RR_TYPE_MX)
333				printf(" has no mail handler record");
334			else if(t == LDNS_RR_TYPE_ANY) {
335				char* s = sldns_wire2str_pkt(
336					result->answer_packet,
337					(size_t)result->answer_len);
338				if(!s) {
339					fprintf(stderr, "alloc failure\n");
340					exit(1);
341				}
342				printf("%s\n", s);
343				free(s);
344			} else	printf(" has no %s record", tstr);
345			printf(" %s\n", secstatus);
346		}
347		/* else: emptiness to indicate no data */
348		if(result->bogus && result->why_bogus)
349			printf("%s\n", result->why_bogus);
350		return;
351	}
352	i=0;
353	while(result->data[i])
354	{
355		pretty_rdata(
356			result->canonname?result->canonname:q,
357			cstr, tstr, t, secstatus, result->data[i],
358			(size_t)result->len[i]);
359		i++;
360	}
361	if(result->bogus && result->why_bogus)
362		printf("%s\n", result->why_bogus);
363}
364
365/** perform a lookup and printout return if domain existed */
366static int
367dnslook(struct ub_ctx* ctx, char* q, int t, int c, int docname)
368{
369	int ret;
370	struct ub_result* result;
371
372	ret = ub_resolve(ctx, q, t, c, &result);
373	if(ret != 0) {
374		fprintf(stderr, "resolve error: %s\n", ub_strerror(ret));
375		exit(1);
376	}
377	pretty_output(q, t, c, result, docname);
378	ret = result->nxdomain;
379	ub_resolve_free(result);
380	return ret;
381}
382
383/** perform host lookup */
384static void
385lookup(struct ub_ctx* ctx, const char* nm, const char* qt, const char* qc)
386{
387	/* massage input into a query name, type and class */
388	int multi = 0;	 /* no type, so do A, AAAA, MX */
389	int reverse = 0; /* we are doing a reverse lookup */
390	char* realq = massage_qname(nm, &reverse);
391	int t = massage_type(qt, reverse, &multi);
392	int c = massage_class(qc);
393
394	/* perform the query */
395	if(multi) {
396		if(!dnslook(ctx, realq, LDNS_RR_TYPE_A, c, 1)) {
397			/* domain exists, lookup more */
398			(void)dnslook(ctx, realq, LDNS_RR_TYPE_AAAA, c, 0);
399			(void)dnslook(ctx, realq, LDNS_RR_TYPE_MX, c, 0);
400		}
401	} else {
402		(void)dnslook(ctx, realq, t, c, 1);
403	}
404	ub_ctx_delete(ctx);
405	free(realq);
406}
407
408/** print error if any */
409static void
410check_ub_res(int r)
411{
412	if(r != 0) {
413		fprintf(stderr, "error: %s\n", ub_strerror(r));
414		exit(1);
415	}
416}
417
418/** getopt global, in case header files fail to declare it. */
419extern int optind;
420/** getopt global, in case header files fail to declare it. */
421extern char* optarg;
422
423/** Main routine for unbound-host */
424int main(int argc, char* argv[])
425{
426	int c;
427	char* qclass = NULL;
428	char* qtype = NULL;
429	char* use_syslog = NULL;
430	struct ub_ctx* ctx = NULL;
431	int debuglevel = 0;
432
433	ctx = ub_ctx_create();
434	if(!ctx) {
435		fprintf(stderr, "error: out of memory\n");
436		exit(1);
437	}
438	/* no need to fetch additional targets, we only do few lookups */
439	check_ub_res(ub_ctx_set_option(ctx, "target-fetch-policy:", "0 0 0 0 0"));
440
441	/* parse the options */
442	while( (c=getopt(argc, argv, "46DF:c:df:hrt:vy:C:")) != -1) {
443		switch(c) {
444		case '4':
445			check_ub_res(ub_ctx_set_option(ctx, "do-ip6:", "no"));
446			break;
447		case '6':
448			check_ub_res(ub_ctx_set_option(ctx, "do-ip4:", "no"));
449			break;
450		case 'c':
451			qclass = optarg;
452			break;
453		case 'C':
454			check_ub_res(ub_ctx_config(ctx, optarg));
455			break;
456		case 'D':
457			check_ub_res(ub_ctx_add_ta_file(ctx, ROOT_ANCHOR_FILE));
458			break;
459		case 'd':
460			debuglevel++;
461			if(debuglevel < 2)
462				debuglevel = 2; /* at least VERB_DETAIL */
463			break;
464		case 'r':
465			check_ub_res(ub_ctx_resolvconf(ctx, "/etc/resolv.conf"));
466			break;
467		case 't':
468			qtype = optarg;
469			break;
470		case 'v':
471			verb++;
472			break;
473		case 'y':
474			check_ub_res(ub_ctx_add_ta(ctx, optarg));
475			break;
476		case 'f':
477			check_ub_res(ub_ctx_add_ta_file(ctx, optarg));
478			break;
479		case 'F':
480			check_ub_res(ub_ctx_trustedkeys(ctx, optarg));
481			break;
482		case '?':
483		case 'h':
484		default:
485			usage();
486		}
487	}
488	if(debuglevel != 0) /* set after possible -C options */
489		check_ub_res(ub_ctx_debuglevel(ctx, debuglevel));
490	if(ub_ctx_get_option(ctx, "use-syslog", &use_syslog) == 0) {
491		if(strcmp(use_syslog, "yes") == 0) /* disable use-syslog */
492			check_ub_res(ub_ctx_set_option(ctx,
493				"use-syslog:", "no"));
494		free(use_syslog);
495	}
496	argc -= optind;
497	argv += optind;
498	if(argc != 1)
499		usage();
500
501#ifdef HAVE_SSL
502#ifdef HAVE_ERR_LOAD_CRYPTO_STRINGS
503	ERR_load_crypto_strings();
504#endif
505#if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_SSL)
506	ERR_load_SSL_strings();
507#endif
508#if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_CRYPTO)
509#  ifndef S_SPLINT_S
510	OpenSSL_add_all_algorithms();
511#  endif
512#else
513	OPENSSL_init_crypto(OPENSSL_INIT_ADD_ALL_CIPHERS
514		| OPENSSL_INIT_ADD_ALL_DIGESTS
515		| OPENSSL_INIT_LOAD_CRYPTO_STRINGS, NULL);
516#endif
517#if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_SSL)
518	(void)SSL_library_init();
519#else
520	(void)OPENSSL_init_ssl(OPENSSL_INIT_LOAD_SSL_STRINGS, NULL);
521#endif
522#endif /* HAVE_SSL */
523#ifdef HAVE_NSS
524        if(NSS_NoDB_Init(".") != SECSuccess) {
525		fprintf(stderr, "could not init NSS\n");
526		return 1;
527	}
528#endif
529	lookup(ctx, argv[0], qtype, qclass);
530	return 0;
531}
532