1 /*
2 * smallapp/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 */
79 static int verb = 0;
80
81 /** Give unbound-host usage, and exit (1). */
82 static void
usage(void)83 usage(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 */
116 static int
isip4(const char * nm,char ** res)117 isip4(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 */
133 static int
isip6(const char * nm,char ** res)134 isip6(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 */
163 static char*
massage_qname(const char * nm,int * reverse)164 massage_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 */
183 static int
massage_type(const char * t,int reverse,int * multi)184 massage_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 */
202 static int
massage_class(const char * c)203 massage_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 */
218 static const char*
secure_str(struct ub_result * result)219 secure_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 */
228 static void
pretty_type(char * s,size_t len,int t)229 pretty_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 */
237 static void
pretty_class(char * s,size_t len,int c)238 pretty_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 */
246 static void
pretty_rcode(char * s,size_t len,int r)247 pretty_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 */
255 static void
print_rd(int t,char * data,size_t len)256 print_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 */
264 static void
pretty_rdata(char * q,char * cstr,char * tstr,int t,const char * sec,char * data,size_t len)265 pretty_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 */
287 static void
pretty_output(char * q,int t,int c,struct ub_result * result,int docname)288 pretty_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 */
366 static int
dnslook(struct ub_ctx * ctx,char * q,int t,int c,int docname)367 dnslook(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 */
384 static void
lookup(struct ub_ctx * ctx,const char * nm,const char * qt,const char * qc)385 lookup(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 */
409 static void
check_ub_res(int r)410 check_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. */
419 extern int optind;
420 /** getopt global, in case header files fail to declare it. */
421 extern char* optarg;
422
423 /** Main routine for unbound-host */
main(int argc,char * argv[])424 int 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 ub_ctx_delete(ctx);
486 usage();
487 }
488 }
489 if(debuglevel != 0) /* set after possible -C options */
490 check_ub_res(ub_ctx_debuglevel(ctx, debuglevel));
491 if(ub_ctx_get_option(ctx, "use-syslog", &use_syslog) == 0) {
492 if(strcmp(use_syslog, "yes") == 0) /* disable use-syslog */
493 check_ub_res(ub_ctx_set_option(ctx,
494 "use-syslog:", "no"));
495 free(use_syslog);
496 }
497 argc -= optind;
498 argv += optind;
499 if(argc != 1) {
500 ub_ctx_delete(ctx);
501 usage();
502 }
503
504 #ifdef HAVE_SSL
505 #ifdef HAVE_ERR_LOAD_CRYPTO_STRINGS
506 ERR_load_crypto_strings();
507 #endif
508 #if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_SSL)
509 ERR_load_SSL_strings();
510 #endif
511 #if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_CRYPTO)
512 # ifndef S_SPLINT_S
513 OpenSSL_add_all_algorithms();
514 # endif
515 #else
516 OPENSSL_init_crypto(OPENSSL_INIT_ADD_ALL_CIPHERS
517 | OPENSSL_INIT_ADD_ALL_DIGESTS
518 | OPENSSL_INIT_LOAD_CRYPTO_STRINGS, NULL);
519 #endif
520 #if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_SSL)
521 (void)SSL_library_init();
522 #else
523 (void)OPENSSL_init_ssl(OPENSSL_INIT_LOAD_SSL_STRINGS, NULL);
524 #endif
525 #endif /* HAVE_SSL */
526 #ifdef HAVE_NSS
527 if(NSS_NoDB_Init(".") != SECSuccess) {
528 fprintf(stderr, "could not init NSS\n");
529 return 1;
530 }
531 #endif
532 lookup(ctx, argv[0], qtype, qclass);
533 return 0;
534 }
535