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 (!(handle = fw3_ipt_open(family, table)))
 199                                 continue;
 200
 201                         info(" * %sing %s %s table", complete ? "Flush" : "Clear",
 202                              fw3_flag_names[family], fw3_flag_names[table]);
 203
 204                         if (complete)
 205                         {
 206                                 fw3_flush_all(handle);
 207                         }
 208                         else if (run_state)
 209                         {
 210                                 fw3_flush_rules(handle, run_state, false);
 211                                 fw3_flush_zones(handle, run_state, false);
 212                         }
 213
 214                         fw3_ipt_commit(handle);
 215                         fw3_ipt_close(handle);
 216                 }
 217
 218                 family_set(run_state, family, false);
 219                 family_set(cfg_state, family, false);
 220
 221                 rv = 0;
 222         }
 223
 224         if (run_state) {
 225                 for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 226                         fw3_destroy_ipsets(run_state, family, false);
 227         }
 228
 229         if (complete)
 230                 fw3_flush_conntrack(NULL);
 231
 232         if (!rv && run_state)
 233                 fw3_write_statefile(run_state);
 234
 235         return rv;
 236 }
 237
 238 static int
 239 start(void)
 240 {
 241         int rv = 1;
 242         enum fw3_family family;
 243         enum fw3_table table;
 244         struct fw3_ipt_handle *handle;
 245
 246         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 247         {
 248                 if (!print_family)
 249                         fw3_create_ipsets(cfg_state, family, false);
 250
 251                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 252                         continue;
 253
 254                 if (print_family && family != print_family)
 255                         continue;
 256
 257                 if (!print_family && family_running(family))
 258                 {
 259                         warn("The %s firewall appears to be started already. "
 260                              "If it is indeed empty, remove the %s file and retry.",
 261                              fw3_flag_names[family], FW3_STATEFILE);
 262
 263                         continue;
 264                 }
 265
 266                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 267                 {
 268                         if (!(handle = fw3_ipt_open(family, table)))
 269                                 continue;
 270
 271                         info(" * Populating %s %s table",
 272                              fw3_flag_names[family], fw3_flag_names[table]);
 273
 274                         fw3_print_default_chains(handle, cfg_state, false);
 275                         fw3_print_zone_chains(handle, cfg_state, false);
 276                         fw3_print_default_head_rules(handle, cfg_state, false);
 277                         fw3_print_rules(handle, cfg_state);
 278                         fw3_print_redirects(handle, cfg_state);
 279                         fw3_print_snats(handle, cfg_state);
 280                         fw3_print_forwards(handle, cfg_state);
 281                         fw3_print_zone_rules(handle, cfg_state, false);
 282                         fw3_print_default_tail_rules(handle, cfg_state, false);
 283
 284                         if (!print_family)
 285                                 fw3_ipt_commit(handle);
 286
 287                         fw3_ipt_close(handle);
 288                 }
 289
 290                 if (!print_family)
 291                         fw3_print_includes(cfg_state, family, false);
 292
 293                 family_set(run_state, family, true);
 294                 family_set(cfg_state, family, true);
 295
 296                 rv = 0;
 297         }
 298
 299         if (!rv)
 300         {
 301                 fw3_flush_conntrack(run_state);
 302                 fw3_set_defaults(cfg_state);
 303
 304                 if (!print_family)
 305                 {
 306                         fw3_run_includes(cfg_state, false);
 307                         fw3_hotplug_zones(cfg_state, true);
 308                         fw3_write_statefile(cfg_state);
 309                 }
 310         }
 311
 312         return rv;
 313 }
 314
 315
 316 static int
 317 reload(void)
 318 {
 319         int rv = 1;
 320         enum fw3_family family;
 321         enum fw3_table table;
 322         struct fw3_ipt_handle *handle;
 323
 324         if (!run_state)
 325                 return start();
 326
 327         fw3_hotplug_zones(run_state, false);
 328
 329         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 330         {
 331                 if (!family_running(family))
 332                         goto start;
 333
 334                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 335                 {
 336                         if (!(handle = fw3_ipt_open(family, table)))
 337                                 continue;
 338
 339                         info(" * Clearing %s %s table",
 340                              fw3_flag_names[family], fw3_flag_names[table]);
 341
 342                         fw3_flush_rules(handle, run_state, true);
 343                         fw3_flush_zones(handle, run_state, true);
 344                         fw3_ipt_commit(handle);
 345                         fw3_ipt_close(handle);
 346                 }
 347
 348                 fw3_ipsets_update_run_state(family, run_state, cfg_state);
 349                 fw3_destroy_ipsets(run_state, family, true);
 350
 351                 family_set(run_state, family, false);
 352                 family_set(cfg_state, family, false);
 353
 354 start:
 355                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 356                         continue;
 357
 358                 fw3_create_ipsets(cfg_state, family, true);
 359
 360                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 361                 {
 362                         if (!(handle = fw3_ipt_open(family, table)))
 363                                 continue;
 364
 365                         info(" * Populating %s %s table",
 366                              fw3_flag_names[family], fw3_flag_names[table]);
 367
 368                         fw3_print_default_chains(handle, cfg_state, true);
 369                         fw3_print_zone_chains(handle, cfg_state, true);
 370                         fw3_print_default_head_rules(handle, cfg_state, true);
 371                         fw3_print_rules(handle, cfg_state);
 372                         fw3_print_redirects(handle, cfg_state);
 373                         fw3_print_snats(handle, cfg_state);
 374                         fw3_print_forwards(handle, cfg_state);
 375                         fw3_print_zone_rules(handle, cfg_state, true);
 376                         fw3_print_default_tail_rules(handle, cfg_state, true);
 377
 378                         fw3_ipt_commit(handle);
 379                         fw3_ipt_close(handle);
 380                 }
 381
 382                 fw3_print_includes(cfg_state, family, true);
 383
 384                 family_set(run_state, family, true);
 385                 family_set(cfg_state, family, true);
 386
 387                 rv = 0;
 388         }
 389
 390         if (!rv)
 391         {
 392                 fw3_flush_conntrack(run_state);
 393
 394                 fw3_set_defaults(cfg_state);
 395                 fw3_run_includes(cfg_state, true);
 396                 fw3_hotplug_zones(cfg_state, true);
 397                 fw3_write_statefile(cfg_state);
 398         }
 399
 400         return rv;
 401 }
 402
 403 static int
 404 gc(void)
 405 {
 406         enum fw3_family family;
 407         enum fw3_table table;
 408         struct fw3_ipt_handle *handle;
 409
 410         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 411         {
 412                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 413                         continue;
 414
 415                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 416                 {
 417                         if (!(handle = fw3_ipt_open(family, table)))
 418                                 continue;
 419
 420                         fw3_ipt_gc(handle);
 421                         fw3_ipt_commit(handle);
 422                         fw3_ipt_close(handle);
 423                 }
 424         }
 425
 426         return 0;
 427 }
 428
 429 static int
 430 lookup_network(const char *net)
 431 {
 432         struct fw3_zone *z;
 433         struct fw3_device *d;
 434
 435         list_for_each_entry(z, &cfg_state->zones, list)
 436         {
 437                 list_for_each_entry(d, &z->networks, list)
 438                 {
 439                         if (!strcmp(d->name, net))
 440                         {
 441                                 printf("%s\n", z->name);
 442                                 return 0;
 443                         }
 444                 }
 445         }
 446
 447         return 1;
 448 }
 449
 450 static int
 451 lookup_device(const char *dev)
 452 {
 453         struct fw3_zone *z;
 454         struct fw3_device *d;
 455
 456         list_for_each_entry(z, &cfg_state->zones, list)
 457         {
 458                 list_for_each_entry(d, &z->devices, list)
 459                 {
 460                         if (!strcmp(d->name, dev))
 461                         {
 462                                 printf("%s\n", z->name);
 463                                 return 0;
 464                         }
 465                 }
 466         }
 467
 468         return 1;
 469 }
 470
 471 static int
 472 lookup_zone(const char *zone, const char *device)
 473 {
 474         struct fw3_zone *z;
 475         struct fw3_device *d;
 476
 477         list_for_each_entry(z, &cfg_state->zones, list)
 478         {
 479                 if (strcmp(z->name, zone))
 480                         continue;
 481
 482                 list_for_each_entry(d, &z->devices, list)
 483                 {
 484                         if (device && strcmp(device, d->name))
 485                                 continue;
 486
 487                         printf("%s\n", d->name);
 488
 489                         if (device)
 490                                 return 0;
 491                 }
 492
 493                 if (!device)
 494                         return 0;
 495         }
 496
 497         return 1;
 498 }
 499
 500 static int
 501 usage(void)
 502 {
 503         fprintf(stderr, "fw3 [-4] [-6] [-q] print\n");
 504         fprintf(stderr, "fw3 [-q] {start|stop|flush|reload|restart}\n");
 505         fprintf(stderr, "fw3 [-q] network {net}\n");
 506         fprintf(stderr, "fw3 [-q] device {dev}\n");
 507         fprintf(stderr, "fw3 [-q] zone {zone} [dev]\n");
 508
 509         return 1;
 510 }
 511
 512
 513 int main(int argc, char **argv)
 514 {
 515         int ch, rv = 1;
 516         enum fw3_family family = FW3_FAMILY_ANY;
 517         struct fw3_defaults *defs = NULL;
 518
 519         while ((ch = getopt(argc, argv, "46dqh")) != -1)
 520         {
 521                 switch (ch)
 522                 {
 523                 case '4':
 524                         family = FW3_FAMILY_V4;
 525                         break;
 526
 527                 case '6':
 528                         family = FW3_FAMILY_V6;
 529                         break;
 530
 531                 case 'd':
 532                         fw3_pr_debug = true;
 533                         break;
 534
 535                 case 'q':
 536                         if (freopen("/dev/null", "w", stderr)) {}
 537                         break;
 538
 539                 case 'h':
 540                         rv = usage();
 541                         goto out;
 542                 }
 543         }
 544
 545         build_state(false);
 546         defs = &cfg_state->defaults;
 547
 548         if (optind >= argc)
 549         {
 550                 rv = usage();
 551                 goto out;
 552         }
 553
 554         if (!strcmp(argv[optind], "print"))
 555         {
 556                 if (family == FW3_FAMILY_ANY)
 557                 {
 558                         family = FW3_FAMILY_V4;
 559                 }
 560                 else if (family == FW3_FAMILY_V6)
 561                 {
 562                         if (defs->disable_ipv6)
 563                                 warn("IPv6 rules globally disabled in configuration");
 564 #ifdef DISABLE_IPV6
 565                         else
 566                                 warn("IPv6 support is not compiled in");
 567 #endif
 568                 }
 569
 570                 if (freopen("/dev/null", "w", stderr)) {};
 571
 572                 cfg_state->disable_ipsets = true;
 573                 print_family = family;
 574                 fw3_pr_debug = true;
 575
 576                 if (fw3_lock())
 577                 {
 578                         build_state(true);
 579                         rv = start();
 580                         fw3_unlock();
 581                 }
 582         }
 583         else if (!strcmp(argv[optind], "start"))
 584         {
 585                 if (fw3_lock())
 586                 {
 587                         build_state(true);
 588                         rv = start();
 589                         fw3_unlock();
 590                 }
 591         }
 592         else if (!strcmp(argv[optind], "stop"))
 593         {
 594                 if (fw3_lock())
 595                 {
 596                         build_state(true);
 597                         rv = stop(false);
 598                         fw3_unlock();
 599                 }
 600         }
 601         else if (!strcmp(argv[optind], "flush"))
 602         {
 603                 if (fw3_lock())
 604                 {
 605                         build_state(true);
 606                         rv = stop(true);
 607                         fw3_unlock();
 608                 }
 609         }
 610         else if (!strcmp(argv[optind], "restart"))
 611         {
 612                 if (fw3_lock())
 613                 {
 614                         build_state(true);
 615                         stop(true);
 616                         rv = start();
 617                         fw3_unlock();
 618                 }
 619         }
 620         else if (!strcmp(argv[optind], "reload"))
 621         {
 622                 if (fw3_lock())
 623                 {
 624                         build_state(true);
 625                         rv = reload();
 626                         fw3_unlock();
 627                 }
 628         }
 629         else if (!strcmp(argv[optind], "gc"))
 630         {
 631                 if (fw3_lock())
 632                 {
 633                         rv = gc();
 634                         fw3_unlock();
 635                 }
 636         }
 637         else if (!strcmp(argv[optind], "network") && (optind + 1) < argc)
 638         {
 639                 rv = lookup_network(argv[optind + 1]);
 640         }
 641         else if (!strcmp(argv[optind], "device") && (optind + 1) < argc)
 642         {
 643                 rv = lookup_device(argv[optind + 1]);
 644         }
 645         else if (!strcmp(argv[optind], "zone") && (optind + 1) < argc)
 646         {
 647                 rv = lookup_zone(argv[optind + 1], argv[optind + 2]);
 648         }
 649         else
 650         {
 651                 rv = usage();
 652         }
 653
 654 out:
 655         if (cfg_state)
 656                 free_state(cfg_state);
 657
 658         if (run_state)
 659                 free_state(run_state);
 660
 661         return rv;
 662 }