unbound/smallapp/unbound-checkconf.c

   1 /*
   2  * checkconf/unbound-checkconf.c - config file checker for unbound.conf file.
   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  * The config checker checks for syntax and other errors in the unbound.conf
  40  * file, and can be used to check for errors before the server is started
  41  * or sigHUPped.
  42  * Exit status 1 means an error.
  43  */
  44
  45 #include "config.h"
  46 #include "util/log.h"
  47 #include "util/config_file.h"
  48 #include "util/module.h"
  49 #include "util/net_help.h"
  50 #include "util/regional.h"
  51 #include "iterator/iterator.h"
  52 #include "iterator/iter_fwd.h"
  53 #include "iterator/iter_hints.h"
  54 #include "validator/validator.h"
  55 #include "services/localzone.h"
  56 #include "ldns/sbuffer.h"
  57 #ifdef HAVE_GETOPT_H
  58 #include <getopt.h>
  59 #endif
  60 #ifdef HAVE_PWD_H
  61 #include <pwd.h>
  62 #endif
  63 #ifdef HAVE_SYS_STAT_H
  64 #include <sys/stat.h>
  65 #endif
  66 #ifdef HAVE_GLOB_H
  67 #include <glob.h>
  68 #endif
  69 #ifdef WITH_PYTHONMODULE
  70 #include "pythonmod/pythonmod.h"
  71 #endif
  72
  73 /** Give checkconf usage, and exit (1). */
  74 static void
  75 usage()
  76 {
  77         printf("Usage:  unbound-checkconf [file]\n");
  78         printf("        Checks unbound configuration file for errors.\n");
  79         printf("file    if omitted %s is used.\n", CONFIGFILE);
  80         printf("-o option       print value of option to stdout.\n");
  81         printf("-h              show this usage help.\n");
  82         printf("Version %s\n", PACKAGE_VERSION);
  83         printf("BSD licensed, see LICENSE in source package for details.\n");
  84         printf("Report bugs to %s\n", PACKAGE_BUGREPORT);
  85         exit(1);
  86 }
  87
  88 /**
  89  * Print given option to stdout
  90  * @param cfg: config
  91  * @param opt: option name without trailing :.
  92  *      This is different from config_set_option.
  93  */
  94 static void
  95 print_option(struct config_file* cfg, const char* opt)
  96 {
  97         if(!config_get_option(cfg, opt, config_print_func, stdout))
  98                 fatal_exit("cannot print option '%s'", opt);
  99 }
 100
 101 /** check if module works with config */
 102 static void
 103 check_mod(struct config_file* cfg, struct module_func_block* fb)
 104 {
 105         struct module_env env;
 106         memset(&env, 0, sizeof(env));
 107         env.cfg = cfg;
 108         env.scratch = regional_create();
 109         env.scratch_buffer = sldns_buffer_new(BUFSIZ);
 110         if(!env.scratch || !env.scratch_buffer)
 111                 fatal_exit("out of memory");
 112         if(!(*fb->init)(&env, 0)) {
 113                 fatal_exit("bad config for %s module", fb->name);
 114         }
 115         (*fb->deinit)(&env, 0);
 116         sldns_buffer_free(env.scratch_buffer);
 117         regional_destroy(env.scratch);
 118 }
 119
 120 /** check localzones */
 121 static void
 122 localzonechecks(struct config_file* cfg)
 123 {
 124         struct local_zones* zs;
 125         if(!(zs = local_zones_create()))
 126                 fatal_exit("out of memory");
 127         if(!local_zones_apply_cfg(zs, cfg))
 128                 fatal_exit("failed local-zone, local-data configuration");
 129         local_zones_delete(zs);
 130 }
 131
 132 /** emit warnings for IP in hosts */
 133 static void
 134 warn_hosts(const char* typ, struct config_stub* list)
 135 {
 136         struct sockaddr_storage a;
 137         socklen_t alen;
 138         struct config_stub* s;
 139         struct config_strlist* h;
 140         for(s=list; s; s=s->next) {
 141                 for(h=s->hosts; h; h=h->next) {
 142                         if(extstrtoaddr(h->str, &a, &alen)) {
 143                                 fprintf(stderr, "unbound-checkconf: warning:"
 144                                   " %s %s: \"%s\" is an IP%s address, "
 145                                   "and when looked up as a host name "
 146                                   "during use may not resolve.\n",
 147                                   s->name, typ, h->str,
 148                                   addr_is_ip6(&a, alen)?"6":"4");
 149                         }
 150                 }
 151         }
 152 }
 153
 154 /** check interface strings */
 155 static void
 156 interfacechecks(struct config_file* cfg)
 157 {
 158         struct sockaddr_storage a;
 159         socklen_t alen;
 160         int i, j;
 161         for(i=0; i<cfg->num_ifs; i++) {
 162                 if(!extstrtoaddr(cfg->ifs[i], &a, &alen)) {
 163                         fatal_exit("cannot parse interface specified as '%s'",
 164                                 cfg->ifs[i]);
 165                 }
 166                 for(j=0; j<cfg->num_ifs; j++) {
 167                         if(i!=j && strcmp(cfg->ifs[i], cfg->ifs[j])==0)
 168                                 fatal_exit("interface: %s present twice, "
 169                                         "cannot bind same ports twice.",
 170                                         cfg->ifs[i]);
 171                 }
 172         }
 173         for(i=0; i<cfg->num_out_ifs; i++) {
 174                 if(!ipstrtoaddr(cfg->out_ifs[i], UNBOUND_DNS_PORT,
 175                         &a, &alen)) {
 176                         fatal_exit("cannot parse outgoing-interface "
 177                                 "specified as '%s'", cfg->out_ifs[i]);
 178                 }
 179                 for(j=0; j<cfg->num_out_ifs; j++) {
 180                         if(i!=j && strcmp(cfg->out_ifs[i], cfg->out_ifs[j])==0)
 181                                 fatal_exit("outgoing-interface: %s present "
 182                                         "twice, cannot bind same ports twice.",
 183                                         cfg->out_ifs[i]);
 184                 }
 185         }
 186 }
 187
 188 /** check acl ips */
 189 static void
 190 aclchecks(struct config_file* cfg)
 191 {
 192         int d;
 193         struct sockaddr_storage a;
 194         socklen_t alen;
 195         struct config_str2list* acl;
 196         for(acl=cfg->acls; acl; acl = acl->next) {
 197                 if(!netblockstrtoaddr(acl->str, UNBOUND_DNS_PORT, &a, &alen,
 198                         &d)) {
 199                         fatal_exit("cannot parse access control address %s %s",
 200                                 acl->str, acl->str2);
 201                 }
 202         }
 203 }
 204
 205 /** true if fname is a file */
 206 static int
 207 is_file(const char* fname)
 208 {
 209         struct stat buf;
 210         if(stat(fname, &buf) < 0) {
 211                 if(errno==EACCES) {
 212                         printf("warning: no search permission for one of the directories in path: %s\n", fname);
 213                         return 1;
 214                 }
 215                 perror(fname);
 216                 return 0;
 217         }
 218         if(S_ISDIR(buf.st_mode)) {
 219                 printf("%s is not a file\n", fname);
 220                 return 0;
 221         }
 222         return 1;
 223 }
 224
 225 /** true if fname is a directory */
 226 static int
 227 is_dir(const char* fname)
 228 {
 229         struct stat buf;
 230         if(stat(fname, &buf) < 0) {
 231                 if(errno==EACCES) {
 232                         printf("warning: no search permission for one of the directories in path: %s\n", fname);
 233                         return 1;
 234                 }
 235                 perror(fname);
 236                 return 0;
 237         }
 238         if(!(S_ISDIR(buf.st_mode))) {
 239                 printf("%s is not a directory\n", fname);
 240                 return 0;
 241         }
 242         return 1;
 243 }
 244
 245 /** get base dir of a fname */
 246 static char*
 247 basedir(char* fname)
 248 {
 249         char* rev;
 250         if(!fname) fatal_exit("out of memory");
 251         rev = strrchr(fname, '/');
 252         if(!rev) return NULL;
 253         if(fname == rev) return NULL;
 254         rev[0] = 0;
 255         return fname;
 256 }
 257
 258 /** check chroot for a file string */
 259 static void
 260 check_chroot_string(const char* desc, char** ss,
 261         const char* chrootdir, struct config_file* cfg)
 262 {
 263         char* str = *ss;
 264         if(str && str[0]) {
 265                 *ss = fname_after_chroot(str, cfg, 1);
 266                 if(!*ss) fatal_exit("out of memory");
 267                 if(!is_file(*ss)) {
 268                         if(chrootdir && chrootdir[0])
 269                                 fatal_exit("%s: \"%s\" does not exist in "
 270                                         "chrootdir %s", desc, str, chrootdir);
 271                         else
 272                                 fatal_exit("%s: \"%s\" does not exist",
 273                                         desc, str);
 274                 }
 275                 /* put in a new full path for continued checking */
 276                 free(str);
 277         }
 278 }
 279
 280 /** check file list, every file must be inside the chroot location */
 281 static void
 282 check_chroot_filelist(const char* desc, struct config_strlist* list,
 283         const char* chrootdir, struct config_file* cfg)
 284 {
 285         struct config_strlist* p;
 286         for(p=list; p; p=p->next) {
 287                 check_chroot_string(desc, &p->str, chrootdir, cfg);
 288         }
 289 }
 290
 291 /** check file list, with wildcard processing */
 292 static void
 293 check_chroot_filelist_wild(const char* desc, struct config_strlist* list,
 294         const char* chrootdir, struct config_file* cfg)
 295 {
 296         struct config_strlist* p;
 297         for(p=list; p; p=p->next) {
 298 #ifdef HAVE_GLOB
 299                 if(strchr(p->str, '*') || strchr(p->str, '[') ||
 300                         strchr(p->str, '?') || strchr(p->str, '{') ||
 301                         strchr(p->str, '~')) {
 302                         char* s = p->str;
 303                         /* adjust whole pattern for chroot and check later */
 304                         p->str = fname_after_chroot(p->str, cfg, 1);
 305                         free(s);
 306                 } else
 307 #endif /* HAVE_GLOB */
 308                         check_chroot_string(desc, &p->str, chrootdir, cfg);
 309         }
 310 }
 311
 312 /** check configuration for errors */
 313 static void
 314 morechecks(struct config_file* cfg, const char* fname)
 315 {
 316         warn_hosts("stub-host", cfg->stubs);
 317         warn_hosts("forward-host", cfg->forwards);
 318         interfacechecks(cfg);
 319         aclchecks(cfg);
 320
 321         if(cfg->verbosity < 0)
 322                 fatal_exit("verbosity value < 0");
 323         if(cfg->num_threads <= 0 || cfg->num_threads > 10000)
 324                 fatal_exit("num_threads value weird");
 325         if(!cfg->do_ip4 && !cfg->do_ip6)
 326                 fatal_exit("ip4 and ip6 are both disabled, pointless");
 327         if(!cfg->do_udp && !cfg->do_tcp)
 328                 fatal_exit("udp and tcp are both disabled, pointless");
 329         if(cfg->edns_buffer_size > cfg->msg_buffer_size)
 330                 fatal_exit("edns-buffer-size larger than msg-buffer-size, "
 331                         "answers will not fit in processing buffer");
 332
 333         if(cfg->chrootdir && cfg->chrootdir[0] &&
 334                 cfg->chrootdir[strlen(cfg->chrootdir)-1] == '/')
 335                 fatal_exit("chootdir %s has trailing slash '/' please remove.",
 336                         cfg->chrootdir);
 337         if(cfg->chrootdir && cfg->chrootdir[0] &&
 338                 !is_dir(cfg->chrootdir)) {
 339                 fatal_exit("bad chroot directory");
 340         }
 341         if(cfg->chrootdir && cfg->chrootdir[0]) {
 342                 char buf[10240];
 343                 buf[0] = 0;
 344                 if(fname[0] != '/') {
 345                         if(getcwd(buf, sizeof(buf)) == NULL)
 346                                 fatal_exit("getcwd: %s", strerror(errno));
 347                         (void)strlcat(buf, "/", sizeof(buf));
 348                 }
 349                 (void)strlcat(buf, fname, sizeof(buf));
 350                 if(strncmp(buf, cfg->chrootdir, strlen(cfg->chrootdir)) != 0)
 351                         fatal_exit("config file %s is not inside chroot %s",
 352                                 buf, cfg->chrootdir);
 353         }
 354         if(cfg->directory && cfg->directory[0]) {
 355                 char* ad = fname_after_chroot(cfg->directory, cfg, 0);
 356                 if(!ad) fatal_exit("out of memory");
 357                 if(!is_dir(ad)) fatal_exit("bad chdir directory");
 358                 free(ad);
 359         }
 360         if( (cfg->chrootdir && cfg->chrootdir[0]) ||
 361             (cfg->directory && cfg->directory[0])) {
 362                 if(cfg->pidfile && cfg->pidfile[0]) {
 363                         char* ad = (cfg->pidfile[0]=='/')?strdup(cfg->pidfile):
 364                                 fname_after_chroot(cfg->pidfile, cfg, 1);
 365                         char* bd = basedir(ad);
 366                         if(bd && !is_dir(bd))
 367                                 fatal_exit("pidfile directory does not exist");
 368                         free(ad);
 369                 }
 370                 if(cfg->logfile && cfg->logfile[0]) {
 371                         char* ad = fname_after_chroot(cfg->logfile, cfg, 1);
 372                         char* bd = basedir(ad);
 373                         if(bd && !is_dir(bd))
 374                                 fatal_exit("logfile directory does not exist");
 375                         free(ad);
 376                 }
 377         }
 378
 379         check_chroot_filelist("file with root-hints",
 380                 cfg->root_hints, cfg->chrootdir, cfg);
 381         check_chroot_filelist("trust-anchor-file",
 382                 cfg->trust_anchor_file_list, cfg->chrootdir, cfg);
 383         check_chroot_filelist("auto-trust-anchor-file",
 384                 cfg->auto_trust_anchor_file_list, cfg->chrootdir, cfg);
 385         check_chroot_filelist_wild("trusted-keys-file",
 386                 cfg->trusted_keys_file_list, cfg->chrootdir, cfg);
 387         check_chroot_string("dlv-anchor-file", &cfg->dlv_anchor_file,
 388                 cfg->chrootdir, cfg);
 389         /* remove chroot setting so that modules are not stripping pathnames*/
 390         free(cfg->chrootdir);
 391         cfg->chrootdir = NULL;
 392
 393         if(strcmp(cfg->module_conf, "iterator") != 0
 394                 && strcmp(cfg->module_conf, "validator iterator") != 0
 395                 && strcmp(cfg->module_conf, "dns64 validator iterator") != 0
 396                 && strcmp(cfg->module_conf, "dns64 iterator") != 0
 397 #ifdef WITH_PYTHONMODULE
 398                 && strcmp(cfg->module_conf, "python iterator") != 0
 399                 && strcmp(cfg->module_conf, "python validator iterator") != 0
 400                 && strcmp(cfg->module_conf, "validator python iterator") != 0
 401                 && strcmp(cfg->module_conf, "dns64 python iterator") != 0
 402                 && strcmp(cfg->module_conf, "dns64 python validator iterator") != 0
 403                 && strcmp(cfg->module_conf, "dns64 validator python iterator") != 0
 404                 && strcmp(cfg->module_conf, "python dns64 iterator") != 0
 405                 && strcmp(cfg->module_conf, "python dns64 validator iterator") != 0
 406 #endif
 407                 ) {
 408                 fatal_exit("module conf '%s' is not known to work",
 409                         cfg->module_conf);
 410         }
 411
 412 #ifdef HAVE_GETPWNAM
 413         if(cfg->username && cfg->username[0]) {
 414                 if(getpwnam(cfg->username) == NULL)
 415                         fatal_exit("user '%s' does not exist.", cfg->username);
 416                 endpwent();
 417         }
 418 #endif
 419         if(cfg->remote_control_enable) {
 420                 check_chroot_string("server-key-file", &cfg->server_key_file,
 421                         cfg->chrootdir, cfg);
 422                 check_chroot_string("server-cert-file", &cfg->server_cert_file,
 423                         cfg->chrootdir, cfg);
 424                 if(!is_file(cfg->control_key_file))
 425                         fatal_exit("control-key-file: \"%s\" does not exist",
 426                                 cfg->control_key_file);
 427                 if(!is_file(cfg->control_cert_file))
 428                         fatal_exit("control-cert-file: \"%s\" does not exist",
 429                                 cfg->control_cert_file);
 430         }
 431
 432         localzonechecks(cfg);
 433 }
 434
 435 /** check forwards */
 436 static void
 437 check_fwd(struct config_file* cfg)
 438 {
 439         struct iter_forwards* fwd = forwards_create();
 440         if(!fwd || !forwards_apply_cfg(fwd, cfg)) {
 441                 fatal_exit("Could not set forward zones");
 442         }
 443         forwards_delete(fwd);
 444 }
 445
 446 /** check hints */
 447 static void
 448 check_hints(struct config_file* cfg)
 449 {
 450         struct iter_hints* hints = hints_create();
 451         if(!hints || !hints_apply_cfg(hints, cfg)) {
 452                 fatal_exit("Could not set root or stub hints");
 453         }
 454         hints_delete(hints);
 455 }
 456
 457 /** check config file */
 458 static void
 459 checkconf(const char* cfgfile, const char* opt)
 460 {
 461         struct config_file* cfg = config_create();
 462         if(!cfg)
 463                 fatal_exit("out of memory");
 464         if(!config_read(cfg, cfgfile, NULL)) {
 465                 /* config_read prints messages to stderr */
 466                 config_delete(cfg);
 467                 exit(1);
 468         }
 469         if(opt) {
 470                 print_option(cfg, opt);
 471                 config_delete(cfg);
 472                 return;
 473         }
 474         morechecks(cfg, cfgfile);
 475         check_mod(cfg, iter_get_funcblock());
 476         check_mod(cfg, val_get_funcblock());
 477 #ifdef WITH_PYTHONMODULE
 478         if(strstr(cfg->module_conf, "python"))
 479                 check_mod(cfg, pythonmod_get_funcblock());
 480 #endif
 481         check_fwd(cfg);
 482         check_hints(cfg);
 483         printf("unbound-checkconf: no errors in %s\n", cfgfile);
 484         config_delete(cfg);
 485 }
 486
 487 /** getopt global, in case header files fail to declare it. */
 488 extern int optind;
 489 /** getopt global, in case header files fail to declare it. */
 490 extern char* optarg;
 491
 492 /** Main routine for checkconf */
 493 int main(int argc, char* argv[])
 494 {
 495         int c;
 496         const char* f;
 497         const char* opt = NULL;
 498         const char* cfgfile = CONFIGFILE;
 499         log_ident_set("unbound-checkconf");
 500         log_init(NULL, 0, NULL);
 501         checklock_start();
 502 #ifdef USE_WINSOCK
 503         /* use registry config file in preference to compiletime location */
 504         if(!(cfgfile=w_lookup_reg_str("Software\\Unbound", "ConfigFile")))
 505                 cfgfile = CONFIGFILE;
 506 #endif /* USE_WINSOCK */
 507         /* parse the options */
 508         while( (c=getopt(argc, argv, "ho:")) != -1) {
 509                 switch(c) {
 510                 case 'o':
 511                         opt = optarg;
 512                         break;
 513                 case '?':
 514                 case 'h':
 515                 default:
 516                         usage();
 517                 }
 518         }
 519         argc -= optind;
 520         argv += optind;
 521         if(argc != 0 && argc != 1)
 522                 usage();
 523         if(argc == 1)
 524                 f = argv[0];
 525         else    f = cfgfile;
 526         checkconf(f, opt);
 527         checklock_stop();
 528         return 0;
 529 }