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 = calloc(1, sizeof(*state));
  49         if (!state)
  50                 error("Out of memory");
  51
  52         state->uci = uci_alloc_context();
  53
  54         if (!state->uci)
  55                 error("Out of memory");
  56
  57         if (runtime)
  58         {
  59                 sf = fopen(FW3_STATEFILE, "r");
  60
  61                 if (sf)
  62                 {
  63                         uci_import(state->uci, sf, "fw3_state", &p, true);
  64                         fclose(sf);
  65                 }
  66
  67                 if (!p)
  68                 {
  69                         uci_free_context(state->uci);
  70                         free(state);
  71
  72                         return false;
  73                 }
  74
  75                 state->statefile = true;
  76
  77                 run_state = state;
  78         }
  79         else
  80         {
  81                 if (!fw3_ubus_connect())
  82                         error("Failed to connect to ubus");
  83
  84                 if (uci_load(state->uci, "firewall", &p))
  85                 {
  86                         uci_perror(state->uci, NULL);
  87                         error("Failed to load /etc/config/firewall");
  88                 }
  89
  90                 if (!fw3_find_command("ipset"))
  91                 {
  92                         warn("Unable to locate ipset utility, disabling ipset support");
  93                         state->disable_ipsets = true;
  94                 }
  95
  96                 cfg_state = state;
  97         }
  98
  99
 100         struct blob_buf b = {NULL, NULL, 0, NULL};
 101         fw3_ubus_rules(&b);
 102
 103         fw3_load_defaults(state, p);
 104         fw3_load_ipsets(state, p);
 105         fw3_load_zones(state, p);
 106         fw3_load_rules(state, p, b.head);
 107         fw3_load_redirects(state, p);
 108         fw3_load_snats(state, p, b.head);
 109         fw3_load_forwards(state, p);
 110         fw3_load_includes(state, p);
 111
 112         return true;
 113 }
 114
 115 static void
 116 free_state(struct fw3_state *state)
 117 {
 118         struct list_head *cur, *tmp;
 119
 120         list_for_each_safe(cur, tmp, &state->zones)
 121                 fw3_free_zone((struct fw3_zone *)cur);
 122
 123         list_for_each_safe(cur, tmp, &state->rules)
 124                 fw3_free_rule((struct fw3_rule *)cur);
 125
 126         list_for_each_safe(cur, tmp, &state->redirects)
 127                 fw3_free_redirect((struct fw3_redirect *)cur);
 128
 129         list_for_each_safe(cur, tmp, &state->snats)
 130                 fw3_free_snat((struct fw3_snat *)cur);
 131
 132         list_for_each_safe(cur, tmp, &state->forwards)
 133                 fw3_free_forward((struct fw3_forward *)cur);
 134
 135         list_for_each_safe(cur, tmp, &state->ipsets)
 136                 fw3_free_ipset((struct fw3_ipset *)cur);
 137
 138         list_for_each_safe(cur, tmp, &state->includes)
 139                 fw3_free_include((struct fw3_include *)cur);
 140
 141         uci_free_context(state->uci);
 142
 143         free(state);
 144
 145         fw3_ubus_disconnect();
 146 }
 147
 148
 149 static bool
 150 family_running(enum fw3_family family)
 151 {
 152         return (run_state && has(run_state->defaults.flags, family, family));
 153 }
 154
 155 static void
 156 family_set(struct fw3_state *state, enum fw3_family family, bool set)
 157 {
 158         if (!state)
 159                 return;
 160
 161         if (set)
 162                 set(state->defaults.flags, family, family);
 163         else
 164                 del(state->defaults.flags, family, family);
 165 }
 166
 167 static int
 168 stop(bool complete)
 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)
 226                 fw3_flush_conntrack(NULL);
 227
 228         if (!rv && run_state)
 229                 fw3_write_statefile(run_state);
 230
 231         return rv;
 232 }
 233
 234 static int
 235 start(void)
 236 {
 237         int rv = 1;
 238         enum fw3_family family;
 239         enum fw3_table table;
 240         struct fw3_ipt_handle *handle;
 241
 242         if (!print_family)
 243                 fw3_create_ipsets(cfg_state);
 244
 245         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 246         {
 247                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 248                         continue;
 249
 250                 if (print_family && family != print_family)
 251                         continue;
 252
 253                 if (!print_family && family_running(family))
 254                 {
 255                         warn("The %s firewall appears to be started already. "
 256                              "If it is indeed empty, remove the %s file and retry.",
 257                              fw3_flag_names[family], FW3_STATEFILE);
 258
 259                         continue;
 260                 }
 261
 262                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 263                 {
 264                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 265                                 continue;
 266
 267                         if (!(handle = fw3_ipt_open(family, table)))
 268                                 continue;
 269
 270                         info(" * Populating %s %s table",
 271                              fw3_flag_names[family], fw3_flag_names[table]);
 272
 273                         fw3_print_default_chains(handle, cfg_state, false);
 274                         fw3_print_zone_chains(handle, cfg_state, false);
 275                         fw3_print_default_head_rules(handle, cfg_state, false);
 276                         fw3_print_rules(handle, cfg_state);
 277                         fw3_print_redirects(handle, cfg_state);
 278                         fw3_print_snats(handle, cfg_state);
 279                         fw3_print_forwards(handle, cfg_state);
 280                         fw3_print_zone_rules(handle, cfg_state, false);
 281                         fw3_print_default_tail_rules(handle, cfg_state, false);
 282
 283                         if (!print_family)
 284                                 fw3_ipt_commit(handle);
 285
 286                         fw3_ipt_close(handle);
 287                 }
 288
 289                 if (!print_family)
 290                         fw3_print_includes(cfg_state, family, false);
 291
 292                 family_set(run_state, family, true);
 293                 family_set(cfg_state, family, true);
 294
 295                 rv = 0;
 296         }
 297
 298         if (!rv)
 299         {
 300                 fw3_flush_conntrack(run_state);
 301                 fw3_set_defaults(cfg_state);
 302
 303                 if (!print_family)
 304                 {
 305                         fw3_run_includes(cfg_state, false);
 306                         fw3_hotplug_zones(cfg_state, true);
 307                         fw3_write_statefile(cfg_state);
 308                 }
 309         }
 310
 311         return rv;
 312 }
 313
 314
 315 static int
 316 reload(void)
 317 {
 318         int rv = 1;
 319         enum fw3_family family;
 320         enum fw3_table table;
 321         struct fw3_ipt_handle *handle;
 322
 323         if (!run_state)
 324                 return start();
 325
 326         fw3_hotplug_zones(run_state, false);
 327
 328         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 329         {
 330                 if (!family_running(family))
 331                         goto start;
 332
 333                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 334                 {
 335                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 336                                 continue;
 337
 338                         if (!(handle = fw3_ipt_open(family, table)))
 339                                 continue;
 340
 341                         info(" * Clearing %s %s table",
 342                              fw3_flag_names[family], fw3_flag_names[table]);
 343
 344                         fw3_flush_rules(handle, run_state, true);
 345                         fw3_flush_zones(handle, run_state, true);
 346                         fw3_ipt_commit(handle);
 347                         fw3_ipt_close(handle);
 348                 }
 349
 350                 family_set(run_state, family, false);
 351                 family_set(cfg_state, family, false);
 352
 353 start:
 354                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 355                         continue;
 356
 357                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 358                 {
 359                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 360                                 continue;
 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 lookup_network(const char *net)
 405 {
 406         struct fw3_zone *z;
 407         struct fw3_device *d;
 408
 409         list_for_each_entry(z, &cfg_state->zones, list)
 410         {
 411                 list_for_each_entry(d, &z->networks, list)
 412                 {
 413                         if (!strcmp(d->name, net))
 414                         {
 415                                 printf("%s\n", z->name);
 416                                 return 0;
 417                         }
 418                 }
 419         }
 420
 421         return 1;
 422 }
 423
 424 static int
 425 lookup_device(const char *dev)
 426 {
 427         struct fw3_zone *z;
 428         struct fw3_device *d;
 429
 430         list_for_each_entry(z, &cfg_state->zones, list)
 431         {
 432                 list_for_each_entry(d, &z->devices, list)
 433                 {
 434                         if (!strcmp(d->name, dev))
 435                         {
 436                                 printf("%s\n", z->name);
 437                                 return 0;
 438                         }
 439                 }
 440         }
 441
 442         return 1;
 443 }
 444
 445 static int
 446 lookup_zone(const char *zone, const char *device)
 447 {
 448         struct fw3_zone *z;
 449         struct fw3_device *d;
 450
 451         list_for_each_entry(z, &cfg_state->zones, list)
 452         {
 453                 if (strcmp(z->name, zone))
 454                         continue;
 455
 456                 list_for_each_entry(d, &z->devices, list)
 457                 {
 458                         if (device && strcmp(device, d->name))
 459                                 continue;
 460
 461                         printf("%s\n", d->name);
 462
 463                         if (device)
 464                                 return 0;
 465                 }
 466
 467                 if (!device)
 468                         return 0;
 469         }
 470
 471         return 1;
 472 }
 473
 474 static int
 475 usage(void)
 476 {
 477         fprintf(stderr, "fw3 [-4] [-6] [-q] print\n");
 478         fprintf(stderr, "fw3 [-q] {start|stop|flush|reload|restart}\n");
 479         fprintf(stderr, "fw3 [-q] network {net}\n");
 480         fprintf(stderr, "fw3 [-q] device {dev}\n");
 481         fprintf(stderr, "fw3 [-q] zone {zone} [dev]\n");
 482
 483         return 1;
 484 }
 485
 486
 487 int main(int argc, char **argv)
 488 {
 489         int ch, rv = 1;
 490         enum fw3_family family = FW3_FAMILY_ANY;
 491         struct fw3_defaults *defs = NULL;
 492
 493         while ((ch = getopt(argc, argv, "46dqh")) != -1)
 494         {
 495                 switch (ch)
 496                 {
 497                 case '4':
 498                         family = FW3_FAMILY_V4;
 499                         break;
 500
 501                 case '6':
 502                         family = FW3_FAMILY_V6;
 503                         break;
 504
 505                 case 'd':
 506                         fw3_pr_debug = true;
 507                         break;
 508
 509                 case 'q':
 510                         if (freopen("/dev/null", "w", stderr)) {}
 511                         break;
 512
 513                 case 'h':
 514                         rv = usage();
 515                         goto out;
 516                 }
 517         }
 518
 519         build_state(false);
 520         build_state(true);
 521         defs = &cfg_state->defaults;
 522
 523         if (optind >= argc)
 524         {
 525                 rv = usage();
 526                 goto out;
 527         }
 528
 529         if (!strcmp(argv[optind], "print"))
 530         {
 531                 if (family == FW3_FAMILY_ANY)
 532                 {
 533                         family = FW3_FAMILY_V4;
 534                 }
 535                 else if (family == FW3_FAMILY_V6)
 536                 {
 537                         if (defs->disable_ipv6)
 538                                 warn("IPv6 rules globally disabled in configuration");
 539 #ifdef DISABLE_IPV6
 540                         else
 541                                 warn("IPv6 support is not compiled in");
 542 #endif
 543                 }
 544
 545                 if (freopen("/dev/null", "w", stderr)) {};
 546
 547                 cfg_state->disable_ipsets = true;
 548                 print_family = family;
 549                 fw3_pr_debug = true;
 550
 551                 rv = start();
 552         }
 553         else if (!strcmp(argv[optind], "start"))
 554         {
 555                 if (fw3_lock())
 556                 {
 557                         rv = start();
 558                         fw3_unlock();
 559                 }
 560         }
 561         else if (!strcmp(argv[optind], "stop"))
 562         {
 563                 if (fw3_lock())
 564                 {
 565                         rv = stop(false);
 566                         fw3_unlock();
 567                 }
 568         }
 569         else if (!strcmp(argv[optind], "flush"))
 570         {
 571                 if (fw3_lock())
 572                 {
 573                         rv = stop(true);
 574                         fw3_unlock();
 575                 }
 576         }
 577         else if (!strcmp(argv[optind], "restart"))
 578         {
 579                 if (fw3_lock())
 580                 {
 581                         stop(true);
 582                         rv = start();
 583                         fw3_unlock();
 584                 }
 585         }
 586         else if (!strcmp(argv[optind], "reload"))
 587         {
 588                 if (fw3_lock())
 589                 {
 590                         rv = reload();
 591                         fw3_unlock();
 592                 }
 593         }
 594         else if (!strcmp(argv[optind], "network") && (optind + 1) < argc)
 595         {
 596                 rv = lookup_network(argv[optind + 1]);
 597         }
 598         else if (!strcmp(argv[optind], "device") && (optind + 1) < argc)
 599         {
 600                 rv = lookup_device(argv[optind + 1]);
 601         }
 602         else if (!strcmp(argv[optind], "zone") && (optind + 1) < argc)
 603         {
 604                 rv = lookup_zone(argv[optind + 1], argv[optind + 2]);
 605         }
 606         else
 607         {
 608                 rv = usage();
 609         }
 610
 611 out:
 612         if (cfg_state)
 613                 free_state(cfg_state);
 614
 615         if (run_state)
 616                 free_state(run_state);
 617
 618         return rv;
 619 }