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                 for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 229                         fw3_destroy_ipsets(run_state, family, false);
 230         }
 231
 232         if (complete)
 233                 fw3_flush_conntrack(NULL);
 234
 235         if (!rv && run_state)
 236                 fw3_write_statefile(run_state);
 237
 238         return rv;
 239 }
 240
 241 static int
 242 start(void)
 243 {
 244         int rv = 1;
 245         enum fw3_family family;
 246         enum fw3_table table;
 247         struct fw3_ipt_handle *handle;
 248
 249         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 250         {
 251                 if (!print_family)
 252                         fw3_create_ipsets(cfg_state, family, false);
 253
 254                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 255                         continue;
 256
 257                 if (print_family && family != print_family)
 258                         continue;
 259
 260                 if (!print_family && family_running(family))
 261                 {
 262                         warn("The %s firewall appears to be started already. "
 263                              "If it is indeed empty, remove the %s file and retry.",
 264                              fw3_flag_names[family], FW3_STATEFILE);
 265
 266                         continue;
 267                 }
 268
 269                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 270                 {
 271                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 272                                 continue;
 273
 274                         if (!(handle = fw3_ipt_open(family, table)))
 275                                 continue;
 276
 277                         info(" * Populating %s %s table",
 278                              fw3_flag_names[family], fw3_flag_names[table]);
 279
 280                         fw3_print_default_chains(handle, cfg_state, false);
 281                         fw3_print_zone_chains(handle, cfg_state, false);
 282                         fw3_print_default_head_rules(handle, cfg_state, false);
 283                         fw3_print_rules(handle, cfg_state);
 284                         fw3_print_redirects(handle, cfg_state);
 285                         fw3_print_snats(handle, cfg_state);
 286                         fw3_print_forwards(handle, cfg_state);
 287                         fw3_print_zone_rules(handle, cfg_state, false);
 288                         fw3_print_default_tail_rules(handle, cfg_state, false);
 289
 290                         if (!print_family)
 291                                 fw3_ipt_commit(handle);
 292
 293                         fw3_ipt_close(handle);
 294                 }
 295
 296                 if (!print_family)
 297                         fw3_print_includes(cfg_state, family, false);
 298
 299                 family_set(run_state, family, true);
 300                 family_set(cfg_state, family, true);
 301
 302                 rv = 0;
 303         }
 304
 305         if (!rv)
 306         {
 307                 fw3_flush_conntrack(run_state);
 308                 fw3_set_defaults(cfg_state);
 309
 310                 if (!print_family)
 311                 {
 312                         fw3_run_includes(cfg_state, false);
 313                         fw3_hotplug_zones(cfg_state, true);
 314                         fw3_write_statefile(cfg_state);
 315                 }
 316         }
 317
 318         return rv;
 319 }
 320
 321
 322 static int
 323 reload(void)
 324 {
 325         int rv = 1;
 326         enum fw3_family family;
 327         enum fw3_table table;
 328         struct fw3_ipt_handle *handle;
 329
 330         if (!run_state)
 331                 return start();
 332
 333         fw3_hotplug_zones(run_state, false);
 334
 335         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 336         {
 337                 if (!family_running(family))
 338                         goto start;
 339
 340                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 341                 {
 342                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 343                                 continue;
 344
 345                         if (!(handle = fw3_ipt_open(family, table)))
 346                                 continue;
 347
 348                         info(" * Clearing %s %s table",
 349                              fw3_flag_names[family], fw3_flag_names[table]);
 350
 351                         fw3_flush_rules(handle, run_state, true);
 352                         fw3_flush_zones(handle, run_state, true);
 353                         fw3_ipt_commit(handle);
 354                         fw3_ipt_close(handle);
 355                 }
 356
 357                 fw3_ipsets_update_run_state(family, run_state, cfg_state);
 358                 fw3_destroy_ipsets(run_state, family, true);
 359
 360                 family_set(run_state, family, false);
 361                 family_set(cfg_state, family, false);
 362
 363 start:
 364                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 365                         continue;
 366
 367                 fw3_create_ipsets(cfg_state, family, true);
 368
 369                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 370                 {
 371                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 372                                 continue;
 373
 374                         if (!(handle = fw3_ipt_open(family, table)))
 375                                 continue;
 376
 377                         info(" * Populating %s %s table",
 378                              fw3_flag_names[family], fw3_flag_names[table]);
 379
 380                         fw3_print_default_chains(handle, cfg_state, true);
 381                         fw3_print_zone_chains(handle, cfg_state, true);
 382                         fw3_print_default_head_rules(handle, cfg_state, true);
 383                         fw3_print_rules(handle, cfg_state);
 384                         fw3_print_redirects(handle, cfg_state);
 385                         fw3_print_snats(handle, cfg_state);
 386                         fw3_print_forwards(handle, cfg_state);
 387                         fw3_print_zone_rules(handle, cfg_state, true);
 388                         fw3_print_default_tail_rules(handle, cfg_state, true);
 389
 390                         fw3_ipt_commit(handle);
 391                         fw3_ipt_close(handle);
 392                 }
 393
 394                 fw3_print_includes(cfg_state, family, true);
 395
 396                 family_set(run_state, family, true);
 397                 family_set(cfg_state, family, true);
 398
 399                 rv = 0;
 400         }
 401
 402         if (!rv)
 403         {
 404                 fw3_flush_conntrack(run_state);
 405
 406                 fw3_set_defaults(cfg_state);
 407                 fw3_run_includes(cfg_state, true);
 408                 fw3_hotplug_zones(cfg_state, true);
 409                 fw3_write_statefile(cfg_state);
 410         }
 411
 412         return rv;
 413 }
 414
 415 static int
 416 gc(void)
 417 {
 418         enum fw3_family family;
 419         enum fw3_table table;
 420         struct fw3_ipt_handle *handle;
 421
 422         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 423         {
 424                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 425                         continue;
 426
 427                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 428                 {
 429                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 430                                 continue;
 431
 432                         if (!(handle = fw3_ipt_open(family, table)))
 433                                 continue;
 434
 435                         fw3_ipt_gc(handle);
 436                         fw3_ipt_commit(handle);
 437                         fw3_ipt_close(handle);
 438                 }
 439         }
 440
 441         return 0;
 442 }
 443
 444 static int
 445 lookup_network(const char *net)
 446 {
 447         struct fw3_zone *z;
 448         struct fw3_device *d;
 449
 450         list_for_each_entry(z, &cfg_state->zones, list)
 451         {
 452                 list_for_each_entry(d, &z->networks, list)
 453                 {
 454                         if (!strcmp(d->name, net))
 455                         {
 456                                 printf("%s\n", z->name);
 457                                 return 0;
 458                         }
 459                 }
 460         }
 461
 462         return 1;
 463 }
 464
 465 static int
 466 lookup_device(const char *dev)
 467 {
 468         struct fw3_zone *z;
 469         struct fw3_device *d;
 470
 471         list_for_each_entry(z, &cfg_state->zones, list)
 472         {
 473                 list_for_each_entry(d, &z->devices, list)
 474                 {
 475                         if (!strcmp(d->name, dev))
 476                         {
 477                                 printf("%s\n", z->name);
 478                                 return 0;
 479                         }
 480                 }
 481         }
 482
 483         return 1;
 484 }
 485
 486 static int
 487 lookup_zone(const char *zone, const char *device)
 488 {
 489         struct fw3_zone *z;
 490         struct fw3_device *d;
 491
 492         list_for_each_entry(z, &cfg_state->zones, list)
 493         {
 494                 if (strcmp(z->name, zone))
 495                         continue;
 496
 497                 list_for_each_entry(d, &z->devices, list)
 498                 {
 499                         if (device && strcmp(device, d->name))
 500                                 continue;
 501
 502                         printf("%s\n", d->name);
 503
 504                         if (device)
 505                                 return 0;
 506                 }
 507
 508                 if (!device)
 509                         return 0;
 510         }
 511
 512         return 1;
 513 }
 514
 515 static int
 516 usage(void)
 517 {
 518         fprintf(stderr, "fw3 [-4] [-6] [-q] print\n");
 519         fprintf(stderr, "fw3 [-q] {start|stop|flush|reload|restart}\n");
 520         fprintf(stderr, "fw3 [-q] network {net}\n");
 521         fprintf(stderr, "fw3 [-q] device {dev}\n");
 522         fprintf(stderr, "fw3 [-q] zone {zone} [dev]\n");
 523
 524         return 1;
 525 }
 526
 527
 528 int main(int argc, char **argv)
 529 {
 530         int ch, rv = 1;
 531         enum fw3_family family = FW3_FAMILY_ANY;
 532         struct fw3_defaults *defs = NULL;
 533
 534         while ((ch = getopt(argc, argv, "46dqh")) != -1)
 535         {
 536                 switch (ch)
 537                 {
 538                 case '4':
 539                         family = FW3_FAMILY_V4;
 540                         break;
 541
 542                 case '6':
 543                         family = FW3_FAMILY_V6;
 544                         break;
 545
 546                 case 'd':
 547                         fw3_pr_debug = true;
 548                         break;
 549
 550                 case 'q':
 551                         if (freopen("/dev/null", "w", stderr)) {}
 552                         break;
 553
 554                 case 'h':
 555                         rv = usage();
 556                         goto out;
 557                 }
 558         }
 559
 560         build_state(false);
 561         defs = &cfg_state->defaults;
 562
 563         if (optind >= argc)
 564         {
 565                 rv = usage();
 566                 goto out;
 567         }
 568
 569         if (!strcmp(argv[optind], "print"))
 570         {
 571                 if (family == FW3_FAMILY_ANY)
 572                 {
 573                         family = FW3_FAMILY_V4;
 574                 }
 575                 else if (family == FW3_FAMILY_V6)
 576                 {
 577                         if (defs->disable_ipv6)
 578                                 warn("IPv6 rules globally disabled in configuration");
 579 #ifdef DISABLE_IPV6
 580                         else
 581                                 warn("IPv6 support is not compiled in");
 582 #endif
 583                 }
 584
 585                 if (freopen("/dev/null", "w", stderr)) {};
 586
 587                 cfg_state->disable_ipsets = true;
 588                 print_family = family;
 589                 fw3_pr_debug = true;
 590
 591                 if (fw3_lock())
 592                 {
 593                         build_state(true);
 594                         rv = start();
 595                         fw3_unlock();
 596                 }
 597         }
 598         else if (!strcmp(argv[optind], "start"))
 599         {
 600                 if (fw3_lock())
 601                 {
 602                         build_state(true);
 603                         rv = start();
 604                         fw3_unlock();
 605                 }
 606         }
 607         else if (!strcmp(argv[optind], "stop"))
 608         {
 609                 if (fw3_lock())
 610                 {
 611                         build_state(true);
 612                         rv = stop(false);
 613                         fw3_unlock();
 614                 }
 615         }
 616         else if (!strcmp(argv[optind], "flush"))
 617         {
 618                 if (fw3_lock())
 619                 {
 620                         build_state(true);
 621                         rv = stop(true);
 622                         fw3_unlock();
 623                 }
 624         }
 625         else if (!strcmp(argv[optind], "restart"))
 626         {
 627                 if (fw3_lock())
 628                 {
 629                         build_state(true);
 630                         stop(true);
 631                         rv = start();
 632                         fw3_unlock();
 633                 }
 634         }
 635         else if (!strcmp(argv[optind], "reload"))
 636         {
 637                 if (fw3_lock())
 638                 {
 639                         build_state(true);
 640                         rv = reload();
 641                         fw3_unlock();
 642                 }
 643         }
 644         else if (!strcmp(argv[optind], "gc"))
 645         {
 646                 if (fw3_lock())
 647                 {
 648                         rv = gc();
 649                         fw3_unlock();
 650                 }
 651         }
 652         else if (!strcmp(argv[optind], "network") && (optind + 1) < argc)
 653         {
 654                 rv = lookup_network(argv[optind + 1]);
 655         }
 656         else if (!strcmp(argv[optind], "device") && (optind + 1) < argc)
 657         {
 658                 rv = lookup_device(argv[optind + 1]);
 659         }
 660         else if (!strcmp(argv[optind], "zone") && (optind + 1) < argc)
 661         {
 662                 rv = lookup_zone(argv[optind + 1], argv[optind + 2]);
 663         }
 664         else
 665         {
 666                 rv = usage();
 667         }
 668
 669 out:
 670         if (cfg_state)
 671                 free_state(cfg_state);
 672
 673         if (run_state)
 674                 free_state(run_state);
 675
 676         return rv;
 677 }