main.c

   1 /*
   2  * firewall3 - 3rd OpenWrt UCI firewall implementation
   3  *
   4  *   Copyright (C) 2013-2014 Jo-Philipp Wich <jo@mein.io>
   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 #include "helpers.h"
  34
  35
  36 static enum fw3_family print_family = FW3_FAMILY_ANY;
  37
  38 static struct fw3_state *run_state = NULL;
  39 static struct fw3_state *cfg_state = NULL;
  40
  41
  42 static bool
  43 build_state(bool runtime)
  44 {
  45         struct fw3_state *state = NULL;
  46         struct uci_package *p = NULL;
  47         FILE *sf;
  48
  49         state = calloc(1, sizeof(*state));
  50         if (!state)
  51                 error("Out of memory");
  52
  53         state->uci = uci_alloc_context();
  54
  55         if (!state->uci)
  56                 error("Out of memory");
  57
  58         if (runtime)
  59         {
  60                 sf = fopen(FW3_STATEFILE, "r");
  61
  62                 if (sf)
  63                 {
  64                         uci_import(state->uci, sf, "fw3_state", &p, true);
  65                         fclose(sf);
  66                 }
  67
  68                 if (!p)
  69                 {
  70                         uci_free_context(state->uci);
  71                         free(state);
  72
  73                         return false;
  74                 }
  75
  76                 state->statefile = true;
  77
  78                 run_state = state;
  79         }
  80         else
  81         {
  82                 if (!fw3_ubus_connect())
  83                         warn("Failed to connect to ubus");
  84
  85                 if (uci_load(state->uci, "firewall", &p))
  86                 {
  87                         uci_perror(state->uci, NULL);
  88                         error("Failed to load /etc/config/firewall");
  89                 }
  90
  91                 if (!fw3_find_command("ipset"))
  92                 {
  93                         warn("Unable to locate ipset utility, disabling ipset support");
  94                         state->disable_ipsets = true;
  95                 }
  96
  97                 cfg_state = state;
  98         }
  99
 100
 101         struct blob_buf b = {NULL, NULL, 0, NULL};
 102         fw3_ubus_rules(&b);
 103
 104         fw3_load_defaults(state, p);
 105         fw3_load_cthelpers(state, p);
 106         fw3_load_ipsets(state, p, b.head);
 107         fw3_load_zones(state, p);
 108         fw3_load_rules(state, p, b.head);
 109         fw3_load_redirects(state, p, b.head);
 110         fw3_load_snats(state, p, b.head);
 111         fw3_load_forwards(state, p, b.head);
 112         fw3_load_includes(state, p, b.head);
 113
 114         return true;
 115 }
 116
 117 static void
 118 free_state(struct fw3_state *state)
 119 {
 120         struct list_head *cur, *tmp;
 121
 122         list_for_each_safe(cur, tmp, &state->zones)
 123                 fw3_free_zone((struct fw3_zone *)cur);
 124
 125         list_for_each_safe(cur, tmp, &state->rules)
 126                 fw3_free_rule((struct fw3_rule *)cur);
 127
 128         list_for_each_safe(cur, tmp, &state->redirects)
 129                 fw3_free_redirect((struct fw3_redirect *)cur);
 130
 131         list_for_each_safe(cur, tmp, &state->snats)
 132                 fw3_free_snat((struct fw3_snat *)cur);
 133
 134         list_for_each_safe(cur, tmp, &state->forwards)
 135                 fw3_free_forward((struct fw3_forward *)cur);
 136
 137         list_for_each_safe(cur, tmp, &state->ipsets)
 138                 fw3_free_ipset((struct fw3_ipset *)cur);
 139
 140         list_for_each_safe(cur, tmp, &state->includes)
 141                 fw3_free_include((struct fw3_include *)cur);
 142
 143         list_for_each_safe(cur, tmp, &state->cthelpers)
 144                 fw3_free_cthelper((struct fw3_cthelper *)cur);
 145
 146         uci_free_context(state->uci);
 147
 148         free(state);
 149
 150         fw3_ubus_disconnect();
 151 }
 152
 153
 154 static bool
 155 family_running(enum fw3_family family)
 156 {
 157         return (run_state && has(run_state->defaults.flags, family, family));
 158 }
 159
 160 static void
 161 family_set(struct fw3_state *state, enum fw3_family family, bool set)
 162 {
 163         if (!state)
 164                 return;
 165
 166         if (set)
 167                 set(state->defaults.flags, family, family);
 168         else
 169                 del(state->defaults.flags, family, family);
 170 }
 171
 172 static int
 173 stop(bool complete)
 174 {
 175         int rv = 1;
 176         enum fw3_family family;
 177         enum fw3_table table;
 178         struct fw3_ipt_handle *handle;
 179
 180         if (!complete && !run_state)
 181         {
 182                 warn("The firewall appears to be stopped. "
 183                          "Use the 'flush' command to forcefully purge all rules.");
 184
 185                 return rv;
 186         }
 187
 188         if (!print_family && run_state)
 189                 fw3_hotplug_zones(run_state, false);
 190
 191         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 192         {
 193                 if (!complete && !family_running(family))
 194                         continue;
 195
 196                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 197                 {
 198                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 199                                 continue;
 200
 201                         if (!(handle = fw3_ipt_open(family, table)))
 202                                 continue;
 203
 204                         info(" * %sing %s %s table", complete ? "Flush" : "Clear",
 205                              fw3_flag_names[family], fw3_flag_names[table]);
 206
 207                         if (complete)
 208                         {
 209                                 fw3_flush_all(handle);
 210                         }
 211                         else if (run_state)
 212                         {
 213                                 fw3_flush_rules(handle, run_state, false);
 214                                 fw3_flush_zones(handle, run_state, false);
 215                         }
 216
 217                         fw3_ipt_commit(handle);
 218                         fw3_ipt_close(handle);
 219                 }
 220
 221                 family_set(run_state, family, false);
 222                 family_set(cfg_state, family, false);
 223
 224                 rv = 0;
 225         }
 226
 227         if (run_state)
 228                 fw3_destroy_ipsets(run_state);
 229
 230         if (complete)
 231                 fw3_flush_conntrack(NULL);
 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_flush_conntrack(run_state);
 306                 fw3_set_defaults(cfg_state);
 307
 308                 if (!print_family)
 309                 {
 310                         fw3_run_includes(cfg_state, false);
 311                         fw3_hotplug_zones(cfg_state, true);
 312                         fw3_write_statefile(cfg_state);
 313                 }
 314         }
 315
 316         return rv;
 317 }
 318
 319
 320 static int
 321 reload(void)
 322 {
 323         int rv = 1;
 324         enum fw3_family family;
 325         enum fw3_table table;
 326         struct fw3_ipt_handle *handle;
 327
 328         if (!run_state)
 329                 return start();
 330
 331         fw3_hotplug_zones(run_state, false);
 332
 333         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 334         {
 335                 if (!family_running(family))
 336                         goto start;
 337
 338                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 339                 {
 340                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 341                                 continue;
 342
 343                         if (!(handle = fw3_ipt_open(family, table)))
 344                                 continue;
 345
 346                         info(" * Clearing %s %s table",
 347                              fw3_flag_names[family], fw3_flag_names[table]);
 348
 349                         fw3_flush_rules(handle, run_state, true);
 350                         fw3_flush_zones(handle, run_state, true);
 351                         fw3_ipt_commit(handle);
 352                         fw3_ipt_close(handle);
 353                 }
 354
 355                 family_set(run_state, family, false);
 356                 family_set(cfg_state, family, false);
 357
 358 start:
 359                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 360                         continue;
 361
 362                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 363                 {
 364                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 365                                 continue;
 366
 367                         if (!(handle = fw3_ipt_open(family, table)))
 368                                 continue;
 369
 370                         info(" * Populating %s %s table",
 371                              fw3_flag_names[family], fw3_flag_names[table]);
 372
 373                         fw3_print_default_chains(handle, cfg_state, true);
 374                         fw3_print_zone_chains(handle, cfg_state, true);
 375                         fw3_print_default_head_rules(handle, cfg_state, true);
 376                         fw3_print_rules(handle, cfg_state);
 377                         fw3_print_redirects(handle, cfg_state);
 378                         fw3_print_snats(handle, cfg_state);
 379                         fw3_print_forwards(handle, cfg_state);
 380                         fw3_print_zone_rules(handle, cfg_state, true);
 381                         fw3_print_default_tail_rules(handle, cfg_state, true);
 382
 383                         fw3_ipt_commit(handle);
 384                         fw3_ipt_close(handle);
 385                 }
 386
 387                 fw3_print_includes(cfg_state, family, true);
 388
 389                 family_set(run_state, family, true);
 390                 family_set(cfg_state, family, true);
 391
 392                 rv = 0;
 393         }
 394
 395         if (!rv)
 396         {
 397                 fw3_flush_conntrack(run_state);
 398
 399                 fw3_set_defaults(cfg_state);
 400                 fw3_run_includes(cfg_state, true);
 401                 fw3_hotplug_zones(cfg_state, true);
 402                 fw3_write_statefile(cfg_state);
 403         }
 404
 405         return rv;
 406 }
 407
 408 static int
 409 gc(void)
 410 {
 411         enum fw3_family family;
 412         enum fw3_table table;
 413         struct fw3_ipt_handle *handle;
 414
 415         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 416         {
 417                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 418                         continue;
 419
 420                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 421                 {
 422                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 423                                 continue;
 424
 425                         if (!(handle = fw3_ipt_open(family, table)))
 426                                 continue;
 427
 428                         fw3_ipt_gc(handle);
 429                         fw3_ipt_commit(handle);
 430                         fw3_ipt_close(handle);
 431                 }
 432         }
 433
 434         return 0;
 435 }
 436
 437 static int
 438 lookup_network(const char *net)
 439 {
 440         struct fw3_zone *z;
 441         struct fw3_device *d;
 442
 443         list_for_each_entry(z, &cfg_state->zones, list)
 444         {
 445                 list_for_each_entry(d, &z->networks, list)
 446                 {
 447                         if (!strcmp(d->name, net))
 448                         {
 449                                 printf("%s\n", z->name);
 450                                 return 0;
 451                         }
 452                 }
 453         }
 454
 455         return 1;
 456 }
 457
 458 static int
 459 lookup_device(const char *dev)
 460 {
 461         struct fw3_zone *z;
 462         struct fw3_device *d;
 463
 464         list_for_each_entry(z, &cfg_state->zones, list)
 465         {
 466                 list_for_each_entry(d, &z->devices, list)
 467                 {
 468                         if (!strcmp(d->name, dev))
 469                         {
 470                                 printf("%s\n", z->name);
 471                                 return 0;
 472                         }
 473                 }
 474         }
 475
 476         return 1;
 477 }
 478
 479 static int
 480 lookup_zone(const char *zone, const char *device)
 481 {
 482         struct fw3_zone *z;
 483         struct fw3_device *d;
 484
 485         list_for_each_entry(z, &cfg_state->zones, list)
 486         {
 487                 if (strcmp(z->name, zone))
 488                         continue;
 489
 490                 list_for_each_entry(d, &z->devices, list)
 491                 {
 492                         if (device && strcmp(device, d->name))
 493                                 continue;
 494
 495                         printf("%s\n", d->name);
 496
 497                         if (device)
 498                                 return 0;
 499                 }
 500
 501                 if (!device)
 502                         return 0;
 503         }
 504
 505         return 1;
 506 }
 507
 508 static int
 509 usage(void)
 510 {
 511         fprintf(stderr, "fw3 [-4] [-6] [-q] print\n");
 512         fprintf(stderr, "fw3 [-q] {start|stop|flush|reload|restart}\n");
 513         fprintf(stderr, "fw3 [-q] network {net}\n");
 514         fprintf(stderr, "fw3 [-q] device {dev}\n");
 515         fprintf(stderr, "fw3 [-q] zone {zone} [dev]\n");
 516
 517         return 1;
 518 }
 519
 520
 521 int main(int argc, char **argv)
 522 {
 523         int ch, rv = 1;
 524         enum fw3_family family = FW3_FAMILY_ANY;
 525         struct fw3_defaults *defs = NULL;
 526
 527         while ((ch = getopt(argc, argv, "46dqh")) != -1)
 528         {
 529                 switch (ch)
 530                 {
 531                 case '4':
 532                         family = FW3_FAMILY_V4;
 533                         break;
 534
 535                 case '6':
 536                         family = FW3_FAMILY_V6;
 537                         break;
 538
 539                 case 'd':
 540                         fw3_pr_debug = true;
 541                         break;
 542
 543                 case 'q':
 544                         if (freopen("/dev/null", "w", stderr)) {}
 545                         break;
 546
 547                 case 'h':
 548                         rv = usage();
 549                         goto out;
 550                 }
 551         }
 552
 553         build_state(false);
 554         defs = &cfg_state->defaults;
 555
 556         if (optind >= argc)
 557         {
 558                 rv = usage();
 559                 goto out;
 560         }
 561
 562         if (!strcmp(argv[optind], "print"))
 563         {
 564                 if (family == FW3_FAMILY_ANY)
 565                 {
 566                         family = FW3_FAMILY_V4;
 567                 }
 568                 else if (family == FW3_FAMILY_V6)
 569                 {
 570                         if (defs->disable_ipv6)
 571                                 warn("IPv6 rules globally disabled in configuration");
 572 #ifdef DISABLE_IPV6
 573                         else
 574                                 warn("IPv6 support is not compiled in");
 575 #endif
 576                 }
 577
 578                 if (freopen("/dev/null", "w", stderr)) {};
 579
 580                 cfg_state->disable_ipsets = true;
 581                 print_family = family;
 582                 fw3_pr_debug = true;
 583
 584                 if (fw3_lock())
 585                 {
 586                         build_state(true);
 587                         rv = start();
 588                         fw3_unlock();
 589                 }
 590         }
 591         else if (!strcmp(argv[optind], "start"))
 592         {
 593                 if (fw3_lock())
 594                 {
 595                         build_state(true);
 596                         rv = start();
 597                         fw3_unlock();
 598                 }
 599         }
 600         else if (!strcmp(argv[optind], "stop"))
 601         {
 602                 if (fw3_lock())
 603                 {
 604                         build_state(true);
 605                         rv = stop(false);
 606                         fw3_unlock();
 607                 }
 608         }
 609         else if (!strcmp(argv[optind], "flush"))
 610         {
 611                 if (fw3_lock())
 612                 {
 613                         build_state(true);
 614                         rv = stop(true);
 615                         fw3_unlock();
 616                 }
 617         }
 618         else if (!strcmp(argv[optind], "restart"))
 619         {
 620                 if (fw3_lock())
 621                 {
 622                         build_state(true);
 623                         stop(true);
 624                         rv = start();
 625                         fw3_unlock();
 626                 }
 627         }
 628         else if (!strcmp(argv[optind], "reload"))
 629         {
 630                 if (fw3_lock())
 631                 {
 632                         build_state(true);
 633                         rv = reload();
 634                         fw3_unlock();
 635                 }
 636         }
 637         else if (!strcmp(argv[optind], "gc"))
 638         {
 639                 if (fw3_lock())
 640                 {
 641                         rv = gc();
 642                         fw3_unlock();
 643                 }
 644         }
 645         else if (!strcmp(argv[optind], "network") && (optind + 1) < argc)
 646         {
 647                 rv = lookup_network(argv[optind + 1]);
 648         }
 649         else if (!strcmp(argv[optind], "device") && (optind + 1) < argc)
 650         {
 651                 rv = lookup_device(argv[optind + 1]);
 652         }
 653         else if (!strcmp(argv[optind], "zone") && (optind + 1) < argc)
 654         {
 655                 rv = lookup_zone(argv[optind + 1], argv[optind + 2]);
 656         }
 657         else
 658         {
 659                 rv = usage();
 660         }
 661
 662 out:
 663         if (cfg_state)
 664                 free_state(cfg_state);
 665
 666         if (run_state)
 667                 free_state(run_state);
 668
 669         return rv;
 670 }