main.c

   1 /*
   2  * firewall3 - 3rd OpenWrt UCI firewall implementation
   3  *
   4  *   Copyright (C) 2013-2014 Jo-Philipp Wich <jow@openwrt.org>
   5  *
   6  * Permission to use, copy, modify, and/or distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #include <stdio.h>
  20 #include <unistd.h>
  21
  22 #include "options.h"
  23 #include "defaults.h"
  24 #include "zones.h"
  25 #include "rules.h"
  26 #include "redirects.h"
  27 #include "snats.h"
  28 #include "forwards.h"
  29 #include "ipsets.h"
  30 #include "includes.h"
  31 #include "ubus.h"
  32 #include "iptables.h"
  33
  34
  35 static enum fw3_family print_family = FW3_FAMILY_ANY;
  36
  37 static struct fw3_state *run_state = NULL;
  38 static struct fw3_state *cfg_state = NULL;
  39
  40
  41 static bool
  42 build_state(bool runtime)
  43 {
  44         struct fw3_state *state = NULL;
  45         struct uci_package *p = NULL;
  46         FILE *sf;
  47
  48         state = malloc(sizeof(*state));
  49
  50         if (!state)
  51                 error("Out of memory");
  52
  53         memset(state, 0, sizeof(*state));
  54         state->uci = uci_alloc_context();
  55
  56         if (!state->uci)
  57                 error("Out of memory");
  58
  59         if (runtime)
  60         {
  61                 sf = fopen(FW3_STATEFILE, "r");
  62
  63                 if (sf)
  64                 {
  65                         uci_import(state->uci, sf, "fw3_state", &p, true);
  66                         fclose(sf);
  67                 }
  68
  69                 if (!p)
  70                 {
  71                         uci_free_context(state->uci);
  72                         free(state);
  73
  74                         return false;
  75                 }
  76
  77                 state->statefile = true;
  78
  79                 run_state = state;
  80         }
  81         else
  82         {
  83                 if (!fw3_ubus_connect())
  84                         error("Failed to connect to ubus");
  85
  86                 if (uci_load(state->uci, "firewall", &p))
  87                 {
  88                         uci_perror(state->uci, NULL);
  89                         error("Failed to load /etc/config/firewall");
  90                 }
  91
  92                 if (!fw3_find_command("ipset"))
  93                 {
  94                         warn("Unable to locate ipset utility, disabling ipset support");
  95                         state->disable_ipsets = true;
  96                 }
  97
  98                 cfg_state = state;
  99         }
 100
 101         fw3_load_defaults(state, p);
 102         fw3_load_ipsets(state, p);
 103         fw3_load_zones(state, p);
 104         fw3_load_rules(state, p);
 105         fw3_load_redirects(state, p);
 106         fw3_load_snats(state, p);
 107         fw3_load_forwards(state, p);
 108         fw3_load_includes(state, p);
 109
 110         return true;
 111 }
 112
 113 static void
 114 free_state(struct fw3_state *state)
 115 {
 116         struct list_head *cur, *tmp;
 117
 118         list_for_each_safe(cur, tmp, &state->zones)
 119                 fw3_free_zone((struct fw3_zone *)cur);
 120
 121         list_for_each_safe(cur, tmp, &state->rules)
 122                 fw3_free_rule((struct fw3_rule *)cur);
 123
 124         list_for_each_safe(cur, tmp, &state->redirects)
 125                 fw3_free_redirect((struct fw3_redirect *)cur);
 126
 127         list_for_each_safe(cur, tmp, &state->snats)
 128                 fw3_free_snat((struct fw3_snat *)cur);
 129
 130         list_for_each_safe(cur, tmp, &state->forwards)
 131                 fw3_free_forward((struct fw3_forward *)cur);
 132
 133         list_for_each_safe(cur, tmp, &state->ipsets)
 134                 fw3_free_ipset((struct fw3_ipset *)cur);
 135
 136         list_for_each_safe(cur, tmp, &state->includes)
 137                 fw3_free_include((struct fw3_include *)cur);
 138
 139         uci_free_context(state->uci);
 140
 141         free(state);
 142
 143         fw3_ubus_disconnect();
 144 }
 145
 146
 147 static bool
 148 family_running(enum fw3_family family)
 149 {
 150         return (run_state && has(run_state->defaults.flags, family, family));
 151 }
 152
 153 static void
 154 family_set(struct fw3_state *state, enum fw3_family family, bool set)
 155 {
 156         if (!state)
 157                 return;
 158
 159         if (set)
 160                 set(state->defaults.flags, family, family);
 161         else
 162                 del(state->defaults.flags, family, family);
 163 }
 164
 165 static int
 166 stop(bool complete)
 167 {
 168         FILE *ct;
 169
 170         int rv = 1;
 171         enum fw3_family family;
 172         enum fw3_table table;
 173         struct fw3_ipt_handle *handle;
 174
 175         if (!complete && !run_state)
 176         {
 177                 warn("The firewall appears to be stopped. "
 178                          "Use the 'flush' command to forcefully purge all rules.");
 179
 180                 return rv;
 181         }
 182
 183         if (!print_family && run_state)
 184                 fw3_hotplug_zones(run_state, false);
 185
 186         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 187         {
 188                 if (!complete && !family_running(family))
 189                         continue;
 190
 191                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 192                 {
 193                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 194                                 continue;
 195
 196                         if (!(handle = fw3_ipt_open(family, table)))
 197                                 continue;
 198
 199                         info(" * %sing %s %s table", complete ? "Flush" : "Clear",
 200                              fw3_flag_names[family], fw3_flag_names[table]);
 201
 202                         if (complete)
 203                         {
 204                                 fw3_flush_all(handle);
 205                         }
 206                         else if (run_state)
 207                         {
 208                                 fw3_flush_rules(handle, run_state, false);
 209                                 fw3_flush_zones(handle, run_state, false);
 210                         }
 211
 212                         fw3_ipt_commit(handle);
 213                         fw3_ipt_close(handle);
 214                 }
 215
 216                 family_set(run_state, family, false);
 217                 family_set(cfg_state, family, false);
 218
 219                 rv = 0;
 220         }
 221
 222         if (run_state)
 223                 fw3_destroy_ipsets(run_state);
 224
 225         if (complete && (ct = fopen("/proc/net/nf_conntrack", "w")) != NULL)
 226         {
 227                 info(" * Flushing conntrack table ...");
 228
 229                 fwrite("f\n", 2, 1, ct);
 230                 fclose(ct);
 231         }
 232
 233         if (!rv && run_state)
 234                 fw3_write_statefile(run_state);
 235
 236         return rv;
 237 }
 238
 239 static int
 240 start(void)
 241 {
 242         int rv = 1;
 243         enum fw3_family family;
 244         enum fw3_table table;
 245         struct fw3_ipt_handle *handle;
 246
 247         if (!print_family)
 248                 fw3_create_ipsets(cfg_state);
 249
 250         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 251         {
 252                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 253                         continue;
 254
 255                 if (print_family && family != print_family)
 256                         continue;
 257
 258                 if (!print_family && family_running(family))
 259                 {
 260                         warn("The %s firewall appears to be started already. "
 261                              "If it is indeed empty, remove the %s file and retry.",
 262                              fw3_flag_names[family], FW3_STATEFILE);
 263
 264                         continue;
 265                 }
 266
 267                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 268                 {
 269                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 270                                 continue;
 271
 272                         if (!(handle = fw3_ipt_open(family, table)))
 273                                 continue;
 274
 275                         info(" * Populating %s %s table",
 276                              fw3_flag_names[family], fw3_flag_names[table]);
 277
 278                         fw3_print_default_chains(handle, cfg_state, false);
 279                         fw3_print_zone_chains(handle, cfg_state, false);
 280                         fw3_print_default_head_rules(handle, cfg_state, false);
 281                         fw3_print_rules(handle, cfg_state);
 282                         fw3_print_redirects(handle, cfg_state);
 283                         fw3_print_snats(handle, cfg_state);
 284                         fw3_print_forwards(handle, cfg_state);
 285                         fw3_print_zone_rules(handle, cfg_state, false);
 286                         fw3_print_default_tail_rules(handle, cfg_state, false);
 287
 288                         if (!print_family)
 289                                 fw3_ipt_commit(handle);
 290
 291                         fw3_ipt_close(handle);
 292                 }
 293
 294                 if (!print_family)
 295                         fw3_print_includes(cfg_state, family, false);
 296
 297                 family_set(run_state, family, true);
 298                 family_set(cfg_state, family, true);
 299
 300                 rv = 0;
 301         }
 302
 303         if (!rv)
 304         {
 305                 fw3_set_defaults(cfg_state);
 306
 307                 if (!print_family)
 308                 {
 309                         fw3_run_includes(cfg_state, false);
 310                         fw3_hotplug_zones(cfg_state, true);
 311                         fw3_write_statefile(cfg_state);
 312                 }
 313         }
 314
 315         return rv;
 316 }
 317
 318
 319 static int
 320 reload(void)
 321 {
 322         int rv = 1;
 323         enum fw3_family family;
 324         enum fw3_table table;
 325         struct fw3_ipt_handle *handle;
 326
 327         if (!run_state)
 328                 return start();
 329
 330         fw3_hotplug_zones(run_state, false);
 331
 332         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 333         {
 334                 if (!family_running(family))
 335                         goto start;
 336
 337                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 338                 {
 339                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 340                                 continue;
 341
 342                         if (!(handle = fw3_ipt_open(family, table)))
 343                                 continue;
 344
 345                         info(" * Clearing %s %s table",
 346                              fw3_flag_names[family], fw3_flag_names[table]);
 347
 348                         fw3_flush_rules(handle, run_state, true);
 349                         fw3_flush_zones(handle, run_state, true);
 350                         fw3_ipt_commit(handle);
 351                         fw3_ipt_close(handle);
 352                 }
 353
 354                 family_set(run_state, family, false);
 355                 family_set(cfg_state, family, false);
 356
 357 start:
 358                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 359                         continue;
 360
 361                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 362                 {
 363                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 364                                 continue;
 365
 366                         if (!(handle = fw3_ipt_open(family, table)))
 367                                 continue;
 368
 369                         info(" * Populating %s %s table",
 370                              fw3_flag_names[family], fw3_flag_names[table]);
 371
 372                         fw3_print_default_chains(handle, cfg_state, true);
 373                         fw3_print_zone_chains(handle, cfg_state, true);
 374                         fw3_print_default_head_rules(handle, cfg_state, true);
 375                         fw3_print_rules(handle, cfg_state);
 376                         fw3_print_redirects(handle, cfg_state);
 377                         fw3_print_snats(handle, cfg_state);
 378                         fw3_print_forwards(handle, cfg_state);
 379                         fw3_print_zone_rules(handle, cfg_state, true);
 380                         fw3_print_default_tail_rules(handle, cfg_state, true);
 381
 382                         fw3_ipt_commit(handle);
 383                         fw3_ipt_close(handle);
 384                 }
 385
 386                 fw3_print_includes(cfg_state, family, true);
 387
 388                 family_set(run_state, family, true);
 389                 family_set(cfg_state, family, true);
 390
 391                 rv = 0;
 392         }
 393
 394         if (!rv)
 395         {
 396                 fw3_set_defaults(cfg_state);
 397                 fw3_run_includes(cfg_state, true);
 398                 fw3_hotplug_zones(cfg_state, true);
 399                 fw3_write_statefile(cfg_state);
 400         }
 401
 402         return rv;
 403 }
 404
 405 static int
 406 lookup_network(const char *net)
 407 {
 408         struct fw3_zone *z;
 409         struct fw3_device *d;
 410
 411         list_for_each_entry(z, &cfg_state->zones, list)
 412         {
 413                 list_for_each_entry(d, &z->networks, list)
 414                 {
 415                         if (!strcmp(d->name, net))
 416                         {
 417                                 printf("%s\n", z->name);
 418                                 return 0;
 419                         }
 420                 }
 421         }
 422
 423         return 1;
 424 }
 425
 426 static int
 427 lookup_device(const char *dev)
 428 {
 429         struct fw3_zone *z;
 430         struct fw3_device *d;
 431
 432         list_for_each_entry(z, &cfg_state->zones, list)
 433         {
 434                 list_for_each_entry(d, &z->devices, list)
 435                 {
 436                         if (!strcmp(d->name, dev))
 437                         {
 438                                 printf("%s\n", z->name);
 439                                 return 0;
 440                         }
 441                 }
 442         }
 443
 444         return 1;
 445 }
 446
 447 static int
 448 usage(void)
 449 {
 450         fprintf(stderr, "fw3 [-4] [-6] [-q] print\n");
 451         fprintf(stderr, "fw3 [-q] {start|stop|flush|reload|restart}\n");
 452         fprintf(stderr, "fw3 [-q] network {net}\n");
 453         fprintf(stderr, "fw3 [-q] device {dev}\n");
 454
 455         return 1;
 456 }
 457
 458
 459 int main(int argc, char **argv)
 460 {
 461         int ch, rv = 1;
 462         enum fw3_family family = FW3_FAMILY_ANY;
 463         struct fw3_defaults *defs = NULL;
 464
 465         while ((ch = getopt(argc, argv, "46dqh")) != -1)
 466         {
 467                 switch (ch)
 468                 {
 469                 case '4':
 470                         family = FW3_FAMILY_V4;
 471                         break;
 472
 473                 case '6':
 474                         family = FW3_FAMILY_V6;
 475                         break;
 476
 477                 case 'd':
 478                         fw3_pr_debug = true;
 479                         break;
 480
 481                 case 'q':
 482                         if (freopen("/dev/null", "w", stderr)) {}
 483                         break;
 484
 485                 case 'h':
 486                         rv = usage();
 487                         goto out;
 488                 }
 489         }
 490
 491         build_state(false);
 492         build_state(true);
 493         defs = &cfg_state->defaults;
 494
 495         if (optind >= argc)
 496         {
 497                 rv = usage();
 498                 goto out;
 499         }
 500
 501         if (!strcmp(argv[optind], "print"))
 502         {
 503                 if (family == FW3_FAMILY_ANY)
 504                 {
 505                         family = FW3_FAMILY_V4;
 506                 }
 507                 else if (family == FW3_FAMILY_V6)
 508                 {
 509                         if (defs->disable_ipv6)
 510                                 warn("IPv6 rules globally disabled in configuration");
 511 #ifdef DISABLE_IPV6
 512                         else
 513                                 warn("IPv6 support is not compiled in");
 514 #endif
 515                 }
 516
 517                 if (freopen("/dev/null", "w", stderr)) {};
 518
 519                 cfg_state->disable_ipsets = true;
 520                 print_family = family;
 521                 fw3_pr_debug = true;
 522
 523                 rv = start();
 524         }
 525         else if (!strcmp(argv[optind], "start"))
 526         {
 527                 if (fw3_lock())
 528                 {
 529                         rv = start();
 530                         fw3_unlock();
 531                 }
 532         }
 533         else if (!strcmp(argv[optind], "stop"))
 534         {
 535                 if (fw3_lock())
 536                 {
 537                         rv = stop(false);
 538                         fw3_unlock();
 539                 }
 540         }
 541         else if (!strcmp(argv[optind], "flush"))
 542         {
 543                 if (fw3_lock())
 544                 {
 545                         rv = stop(true);
 546                         fw3_unlock();
 547                 }
 548         }
 549         else if (!strcmp(argv[optind], "restart"))
 550         {
 551                 if (fw3_lock())
 552                 {
 553                         stop(true);
 554                         rv = start();
 555                         fw3_unlock();
 556                 }
 557         }
 558         else if (!strcmp(argv[optind], "reload"))
 559         {
 560                 if (fw3_lock())
 561                 {
 562                         rv = reload();
 563                         fw3_unlock();
 564                 }
 565         }
 566         else if (!strcmp(argv[optind], "network") && (optind + 1) < argc)
 567         {
 568                 rv = lookup_network(argv[optind + 1]);
 569         }
 570         else if (!strcmp(argv[optind], "device") && (optind + 1) < argc)
 571         {
 572                 rv = lookup_device(argv[optind + 1]);
 573         }
 574         else
 575         {
 576                 rv = usage();
 577         }
 578
 579 out:
 580         if (cfg_state)
 581                 free_state(cfg_state);
 582
 583         if (run_state)
 584                 free_state(run_state);
 585
 586         return rv;
 587 }