unbound/smallapp/unbound-host.c

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