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 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 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 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* 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 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 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* 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 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 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 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 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 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 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 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 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 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 */ 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 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