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         FILE *ct;
 171
 172         int rv = 1;
 173         enum fw3_family family;
 174         enum fw3_table table;
 175         struct fw3_ipt_handle *handle;
 176
 177         if (!complete && !run_state)
 178         {
 179                 warn("The firewall appears to be stopped. "
 180                          "Use the 'flush' command to forcefully purge all rules.");
 181
 182                 return rv;
 183         }
 184
 185         if (!print_family && run_state)
 186                 fw3_hotplug_zones(run_state, false);
 187
 188         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 189         {
 190                 if (!complete && !family_running(family))
 191                         continue;
 192
 193                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 194                 {
 195                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 196                                 continue;
 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                 fw3_destroy_ipsets(run_state);
 226
 227         if (complete && (ct = fopen("/proc/net/nf_conntrack", "w")) != NULL)
 228         {
 229                 info(" * Flushing conntrack table ...");
 230
 231                 fwrite("f\n", 2, 1, ct);
 232                 fclose(ct);
 233         }
 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         if (!print_family)
 250                 fw3_create_ipsets(cfg_state);
 251
 252         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 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_set_defaults(cfg_state);
 308
 309                 if (!print_family)
 310                 {
 311                         fw3_run_includes(cfg_state, false);
 312                         fw3_hotplug_zones(cfg_state, true);
 313                         fw3_write_statefile(cfg_state);
 314                 }
 315         }
 316
 317         return rv;
 318 }
 319
 320
 321 static int
 322 reload(void)
 323 {
 324         int rv = 1;
 325         enum fw3_family family;
 326         enum fw3_table table;
 327         struct fw3_ipt_handle *handle;
 328
 329         if (!run_state)
 330                 return start();
 331
 332         fw3_hotplug_zones(run_state, false);
 333
 334         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 335         {
 336                 if (!family_running(family))
 337                         goto start;
 338
 339                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 340                 {
 341                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 342                                 continue;
 343
 344                         if (!(handle = fw3_ipt_open(family, table)))
 345                                 continue;
 346
 347                         info(" * Clearing %s %s table",
 348                              fw3_flag_names[family], fw3_flag_names[table]);
 349
 350                         fw3_flush_rules(handle, run_state, true);
 351                         fw3_flush_zones(handle, run_state, true);
 352                         fw3_ipt_commit(handle);
 353                         fw3_ipt_close(handle);
 354                 }
 355
 356                 family_set(run_state, family, false);
 357                 family_set(cfg_state, family, false);
 358
 359 start:
 360                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 361                         continue;
 362
 363                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 364                 {
 365                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 366                                 continue;
 367
 368                         if (!(handle = fw3_ipt_open(family, table)))
 369                                 continue;
 370
 371                         info(" * Populating %s %s table",
 372                              fw3_flag_names[family], fw3_flag_names[table]);
 373
 374                         fw3_print_default_chains(handle, cfg_state, true);
 375                         fw3_print_zone_chains(handle, cfg_state, true);
 376                         fw3_print_default_head_rules(handle, cfg_state, true);
 377                         fw3_print_rules(handle, cfg_state);
 378                         fw3_print_redirects(handle, cfg_state);
 379                         fw3_print_snats(handle, cfg_state);
 380                         fw3_print_forwards(handle, cfg_state);
 381                         fw3_print_zone_rules(handle, cfg_state, true);
 382                         fw3_print_default_tail_rules(handle, cfg_state, true);
 383
 384                         fw3_ipt_commit(handle);
 385                         fw3_ipt_close(handle);
 386                 }
 387
 388                 fw3_print_includes(cfg_state, family, true);
 389
 390                 family_set(run_state, family, true);
 391                 family_set(cfg_state, family, true);
 392
 393                 rv = 0;
 394         }
 395
 396         if (!rv)
 397         {
 398                 fw3_set_defaults(cfg_state);
 399                 fw3_run_includes(cfg_state, true);
 400                 fw3_hotplug_zones(cfg_state, true);
 401                 fw3_write_statefile(cfg_state);
 402         }
 403
 404         return rv;
 405 }
 406
 407 static int
 408 lookup_network(const char *net)
 409 {
 410         struct fw3_zone *z;
 411         struct fw3_device *d;
 412
 413         list_for_each_entry(z, &cfg_state->zones, list)
 414         {
 415                 list_for_each_entry(d, &z->networks, list)
 416                 {
 417                         if (!strcmp(d->name, net))
 418                         {
 419                                 printf("%s\n", z->name);
 420                                 return 0;
 421                         }
 422                 }
 423         }
 424
 425         return 1;
 426 }
 427
 428 static int
 429 lookup_device(const char *dev)
 430 {
 431         struct fw3_zone *z;
 432         struct fw3_device *d;
 433
 434         list_for_each_entry(z, &cfg_state->zones, list)
 435         {
 436                 list_for_each_entry(d, &z->devices, list)
 437                 {
 438                         if (!strcmp(d->name, dev))
 439                         {
 440                                 printf("%s\n", z->name);
 441                                 return 0;
 442                         }
 443                 }
 444         }
 445
 446         return 1;
 447 }
 448
 449 static int
 450 lookup_zone(const char *zone, const char *device)
 451 {
 452         struct fw3_zone *z;
 453         struct fw3_device *d;
 454
 455         list_for_each_entry(z, &cfg_state->zones, list)
 456         {
 457                 if (strcmp(z->name, zone))
 458                         continue;
 459
 460                 list_for_each_entry(d, &z->devices, list)
 461                 {
 462                         if (device && strcmp(device, d->name))
 463                                 continue;
 464
 465                         printf("%s\n", d->name);
 466
 467                         if (device)
 468                                 return 0;
 469                 }
 470
 471                 if (!device)
 472                         return 0;
 473         }
 474
 475         return 1;
 476 }
 477
 478 static int
 479 usage(void)
 480 {
 481         fprintf(stderr, "fw3 [-4] [-6] [-q] print\n");
 482         fprintf(stderr, "fw3 [-q] {start|stop|flush|reload|restart}\n");
 483         fprintf(stderr, "fw3 [-q] network {net}\n");
 484         fprintf(stderr, "fw3 [-q] device {dev}\n");
 485         fprintf(stderr, "fw3 [-q] zone {zone} [dev]\n");
 486
 487         return 1;
 488 }
 489
 490
 491 int main(int argc, char **argv)
 492 {
 493         int ch, rv = 1;
 494         enum fw3_family family = FW3_FAMILY_ANY;
 495         struct fw3_defaults *defs = NULL;
 496
 497         while ((ch = getopt(argc, argv, "46dqh")) != -1)
 498         {
 499                 switch (ch)
 500                 {
 501                 case '4':
 502                         family = FW3_FAMILY_V4;
 503                         break;
 504
 505                 case '6':
 506                         family = FW3_FAMILY_V6;
 507                         break;
 508
 509                 case 'd':
 510                         fw3_pr_debug = true;
 511                         break;
 512
 513                 case 'q':
 514                         if (freopen("/dev/null", "w", stderr)) {}
 515                         break;
 516
 517                 case 'h':
 518                         rv = usage();
 519                         goto out;
 520                 }
 521         }
 522
 523         build_state(false);
 524         build_state(true);
 525         defs = &cfg_state->defaults;
 526
 527         if (optind >= argc)
 528         {
 529                 rv = usage();
 530                 goto out;
 531         }
 532
 533         if (!strcmp(argv[optind], "print"))
 534         {
 535                 if (family == FW3_FAMILY_ANY)
 536                 {
 537                         family = FW3_FAMILY_V4;
 538                 }
 539                 else if (family == FW3_FAMILY_V6)
 540                 {
 541                         if (defs->disable_ipv6)
 542                                 warn("IPv6 rules globally disabled in configuration");
 543 #ifdef DISABLE_IPV6
 544                         else
 545                                 warn("IPv6 support is not compiled in");
 546 #endif
 547                 }
 548
 549                 if (freopen("/dev/null", "w", stderr)) {};
 550
 551                 cfg_state->disable_ipsets = true;
 552                 print_family = family;
 553                 fw3_pr_debug = true;
 554
 555                 rv = start();
 556         }
 557         else if (!strcmp(argv[optind], "start"))
 558         {
 559                 if (fw3_lock())
 560                 {
 561                         rv = start();
 562                         fw3_unlock();
 563                 }
 564         }
 565         else if (!strcmp(argv[optind], "stop"))
 566         {
 567                 if (fw3_lock())
 568                 {
 569                         rv = stop(false);
 570                         fw3_unlock();
 571                 }
 572         }
 573         else if (!strcmp(argv[optind], "flush"))
 574         {
 575                 if (fw3_lock())
 576                 {
 577                         rv = stop(true);
 578                         fw3_unlock();
 579                 }
 580         }
 581         else if (!strcmp(argv[optind], "restart"))
 582         {
 583                 if (fw3_lock())
 584                 {
 585                         stop(true);
 586                         rv = start();
 587                         fw3_unlock();
 588                 }
 589         }
 590         else if (!strcmp(argv[optind], "reload"))
 591         {
 592                 if (fw3_lock())
 593                 {
 594                         rv = reload();
 595                         fw3_unlock();
 596                 }
 597         }
 598         else if (!strcmp(argv[optind], "network") && (optind + 1) < argc)
 599         {
 600                 rv = lookup_network(argv[optind + 1]);
 601         }
 602         else if (!strcmp(argv[optind], "device") && (optind + 1) < argc)
 603         {
 604                 rv = lookup_device(argv[optind + 1]);
 605         }
 606         else if (!strcmp(argv[optind], "zone") && (optind + 1) < argc)
 607         {
 608                 rv = lookup_zone(argv[optind + 1], argv[optind + 2]);
 609         }
 610         else
 611         {
 612                 rv = usage();
 613         }
 614
 615 out:
 616         if (cfg_state)
 617                 free_state(cfg_state);
 618
 619         if (run_state)
 620                 free_state(run_state);
 621
 622         return rv;
 623 }