main.c

   1 /*
   2  * firewall3 - 3rd OpenWrt UCI firewall implementation
   3  *
   4  *   Copyright (C) 2013 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 "forwards.h"
  28 #include "ipsets.h"
  29 #include "includes.h"
  30 #include "ubus.h"
  31
  32
  33 static bool print_rules = false;
  34
  35 static struct fw3_state *run_state = NULL;
  36 static struct fw3_state *cfg_state = NULL;
  37
  38
  39 static bool
  40 build_state(bool runtime)
  41 {
  42         struct fw3_state *state = NULL;
  43         struct uci_package *p = NULL;
  44         FILE *sf;
  45
  46         state = malloc(sizeof(*state));
  47
  48         if (!state)
  49                 error("Out of memory");
  50
  51         memset(state, 0, sizeof(*state));
  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         fw3_load_defaults(state, p);
 100         fw3_load_ipsets(state, p);
 101         fw3_load_zones(state, p);
 102         fw3_load_rules(state, p);
 103         fw3_load_redirects(state, p);
 104         fw3_load_forwards(state, p);
 105         fw3_load_includes(state, p);
 106
 107         return true;
 108 }
 109
 110 static void
 111 free_state(struct fw3_state *state)
 112 {
 113         struct list_head *cur, *tmp;
 114
 115         list_for_each_safe(cur, tmp, &state->zones)
 116                 fw3_free_zone((struct fw3_zone *)cur);
 117
 118         list_for_each_safe(cur, tmp, &state->rules)
 119                 fw3_free_rule((struct fw3_rule *)cur);
 120
 121         list_for_each_safe(cur, tmp, &state->redirects)
 122                 fw3_free_redirect((struct fw3_redirect *)cur);
 123
 124         list_for_each_safe(cur, tmp, &state->forwards)
 125                 fw3_free_forward((struct fw3_forward *)cur);
 126
 127         list_for_each_safe(cur, tmp, &state->ipsets)
 128                 fw3_free_ipset((struct fw3_ipset *)cur);
 129
 130         list_for_each_safe(cur, tmp, &state->includes)
 131                 fw3_free_include((struct fw3_include *)cur);
 132
 133         uci_free_context(state->uci);
 134
 135         free(state);
 136
 137         fw3_ubus_disconnect();
 138 }
 139
 140
 141 static bool
 142 restore_pipe(enum fw3_family family, bool silent)
 143 {
 144         const char *cmd;
 145
 146         cmd = (family == FW3_FAMILY_V4) ? "iptables-restore" : "ip6tables-restore";
 147
 148         if (print_rules)
 149                 return fw3_stdout_pipe();
 150
 151         if (!fw3_command_pipe(silent, cmd, "--lenient", "--noflush"))
 152         {
 153                 warn("Unable to execute %s", cmd);
 154                 return false;
 155         }
 156
 157         return true;
 158 }
 159
 160 static bool
 161 family_running(enum fw3_family family)
 162 {
 163         return (run_state && has(run_state->defaults.flags, family, family));
 164 }
 165
 166 static void
 167 family_set(struct fw3_state *state, enum fw3_family family, bool set)
 168 {
 169         if (!state)
 170                 return;
 171
 172         if (set)
 173                 set(state->defaults.flags, family, family);
 174         else
 175                 del(state->defaults.flags, family, family);
 176 }
 177
 178 static int
 179 stop(bool complete)
 180 {
 181         FILE *ct;
 182
 183         int rv = 1;
 184         enum fw3_family family;
 185         enum fw3_table table;
 186
 187         if (!complete && !run_state)
 188         {
 189                 warn("The firewall appears to be stopped. "
 190                          "Use the 'flush' command to forcefully purge all rules.");
 191
 192                 return rv;
 193         }
 194
 195         if (!print_rules && run_state)
 196                 fw3_hotplug_zones(run_state, false);
 197
 198         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 199         {
 200                 if (!complete && !family_running(family))
 201                         continue;
 202
 203                 if (!restore_pipe(family, true))
 204                         continue;
 205
 206                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 207                 {
 208                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 209                                 continue;
 210
 211                         info(" * %sing %s %s table", complete ? "Flush" : "Clear",
 212                              fw3_flag_names[family], fw3_flag_names[table]);
 213
 214                         fw3_pr("*%s\n", fw3_flag_names[table]);
 215
 216                         if (complete)
 217                         {
 218                                 fw3_flush_all(table);
 219                         }
 220                         else if (run_state)
 221                         {
 222                                 /* pass 1 */
 223                                 fw3_flush_rules(run_state, family, table, false, false);
 224                                 fw3_flush_zones(run_state, family, table, false, false);
 225
 226                                 /* pass 2 */
 227                                 fw3_flush_rules(run_state, family, table, false, true);
 228                                 fw3_flush_zones(run_state, family, table, false, true);
 229                         }
 230
 231                         fw3_pr("COMMIT\n");
 232                 }
 233
 234                 fw3_command_close();
 235                 family_set(run_state, family, false);
 236                 family_set(cfg_state, family, false);
 237
 238                 rv = 0;
 239         }
 240
 241         if (run_state)
 242         {
 243                 if (fw3_command_pipe(false, "ipset", "-exist", "-"))
 244                 {
 245                         fw3_destroy_ipsets(run_state);
 246                         fw3_command_close();
 247                 }
 248         }
 249
 250         if (complete && (ct = fopen("/proc/net/nf_conntrack", "w")) != NULL)
 251         {
 252                 info(" * Flushing conntrack table ...");
 253
 254                 fwrite("f\n", 2, 1, ct);
 255                 fclose(ct);
 256         }
 257
 258         if (!rv && run_state)
 259                 fw3_write_statefile(run_state);
 260
 261         return rv;
 262 }
 263
 264 static int
 265 start(void)
 266 {
 267         int rv = 1;
 268         enum fw3_family family;
 269         enum fw3_table table;
 270
 271         if (!print_rules)
 272         {
 273                 if (fw3_command_pipe(false, "ipset", "-exist", "-"))
 274                 {
 275                         fw3_create_ipsets(cfg_state);
 276                         fw3_command_close();
 277                 }
 278         }
 279
 280         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 281         {
 282                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 283                         continue;
 284
 285                 if (!print_rules && family_running(family))
 286                 {
 287                         warn("The %s firewall appears to be started already. "
 288                              "If it is indeed empty, remove the %s file and retry.",
 289                              fw3_flag_names[family], FW3_STATEFILE);
 290
 291                         continue;
 292                 }
 293
 294                 if (!restore_pipe(family, false))
 295                         continue;
 296
 297                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 298                 {
 299                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 300                                 continue;
 301
 302                         info(" * Populating %s %s table",
 303                              fw3_flag_names[family], fw3_flag_names[table]);
 304
 305                         fw3_pr("*%s\n", fw3_flag_names[table]);
 306                         fw3_print_default_chains(cfg_state, family, table, false);
 307                         fw3_print_zone_chains(cfg_state, family, table, false);
 308                         fw3_print_default_head_rules(cfg_state, family, table, false);
 309                         fw3_print_rules(cfg_state, family, table);
 310                         fw3_print_redirects(cfg_state, family, table);
 311                         fw3_print_forwards(cfg_state, family, table);
 312                         fw3_print_zone_rules(cfg_state, family, table, false);
 313                         fw3_print_default_tail_rules(cfg_state, family, table, false);
 314                         fw3_pr("COMMIT\n");
 315                 }
 316
 317                 fw3_print_includes(cfg_state, family, false);
 318
 319                 fw3_command_close();
 320                 family_set(run_state, family, true);
 321                 family_set(cfg_state, family, true);
 322
 323                 rv = 0;
 324         }
 325
 326         if (!rv)
 327         {
 328                 fw3_set_defaults(cfg_state);
 329
 330                 if (!print_rules)
 331                 {
 332                         fw3_run_includes(cfg_state, false);
 333                         fw3_hotplug_zones(cfg_state, true);
 334                         fw3_write_statefile(cfg_state);
 335                 }
 336         }
 337
 338         return rv;
 339 }
 340
 341
 342 static int
 343 reload(void)
 344 {
 345         int rv = 1;
 346         enum fw3_family family;
 347         enum fw3_table table;
 348
 349         if (!print_rules && run_state)
 350                 fw3_hotplug_zones(run_state, false);
 351
 352         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 353         {
 354                 if (!restore_pipe(family, true))
 355                         continue;
 356
 357                 if (!family_running(family))
 358                         goto start;
 359
 360                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 361                 {
 362                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 363                                 continue;
 364
 365                         info(" * Clearing %s %s table",
 366                              fw3_flag_names[family], fw3_flag_names[table]);
 367
 368                         fw3_pr("*%s\n", fw3_flag_names[table]);
 369
 370                         if (run_state)
 371                         {
 372                                 /* pass 1 */
 373                                 fw3_flush_rules(run_state, family, table, true, false);
 374                                 fw3_flush_zones(run_state, family, table, true, false);
 375
 376                                 /* pass 2 */
 377                                 fw3_flush_rules(run_state, family, table, true, true);
 378                                 fw3_flush_zones(run_state, family, table, true, true);
 379                         }
 380
 381                         fw3_pr("COMMIT\n");
 382                 }
 383
 384                 family_set(run_state, family, false);
 385                 family_set(cfg_state, family, false);
 386
 387 start:
 388                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 389                         goto skip;
 390
 391                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 392                 {
 393                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 394                                 continue;
 395
 396                         info(" * Populating %s %s table",
 397                              fw3_flag_names[family], fw3_flag_names[table]);
 398
 399                         fw3_pr("*%s\n", fw3_flag_names[table]);
 400                         fw3_print_default_chains(cfg_state, family, table, true);
 401                         fw3_print_zone_chains(cfg_state, family, table, true);
 402                         fw3_print_default_head_rules(cfg_state, family, table, true);
 403                         fw3_print_rules(cfg_state, family, table);
 404                         fw3_print_redirects(cfg_state, family, table);
 405                         fw3_print_forwards(cfg_state, family, table);
 406                         fw3_print_zone_rules(cfg_state, family, table, true);
 407                         fw3_print_default_tail_rules(cfg_state, family, table, true);
 408                         fw3_pr("COMMIT\n");
 409                 }
 410
 411                 fw3_print_includes(cfg_state, family, true);
 412
 413                 family_set(run_state, family, true);
 414                 family_set(cfg_state, family, true);
 415
 416                 rv = 0;
 417
 418 skip:
 419                 fw3_command_close();
 420         }
 421
 422         if (!rv)
 423         {
 424                 fw3_set_defaults(cfg_state);
 425
 426                 if (!print_rules)
 427                 {
 428                         fw3_run_includes(cfg_state, true);
 429                         fw3_hotplug_zones(cfg_state, true);
 430                         fw3_write_statefile(cfg_state);
 431                 }
 432         }
 433
 434         return rv;
 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 usage(void)
 481 {
 482         fprintf(stderr, "fw3 [-4] [-6] [-q] print\n");
 483         fprintf(stderr, "fw3 [-q] {start|stop|flush|reload|restart}\n");
 484         fprintf(stderr, "fw3 [-q] network {net}\n");
 485         fprintf(stderr, "fw3 [-q] device {dev}\n");
 486
 487         return 1;
 488 }
 489
 490
 491 int main(int argc, char **argv)
 492 {
 493         int ch, rv = 1;
 494         struct fw3_defaults *defs = NULL;
 495         enum fw3_family use_family = FW3_FAMILY_ANY;
 496
 497         while ((ch = getopt(argc, argv, "46dqh")) != -1)
 498         {
 499                 switch (ch)
 500                 {
 501                 case '4':
 502                         use_family = FW3_FAMILY_V4;
 503                         break;
 504
 505                 case '6':
 506                         use_family = FW3_FAMILY_V6;
 507                         break;
 508
 509                 case 'd':
 510                         fw3_pr_debug = true;
 511                         break;
 512
 513                 case 'q':
 514                         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 (use_family == FW3_FAMILY_ANY)
 536                         use_family = FW3_FAMILY_V4;
 537                 else if (use_family == FW3_FAMILY_V6 && defs->disable_ipv6)
 538                         warn("IPv6 rules globally disabled in configuration");
 539
 540                 freopen("/dev/null", "w", stderr);
 541
 542                 cfg_state->disable_ipsets = true;
 543                 print_rules = true;
 544
 545                 rv = start();
 546         }
 547         else if (!strcmp(argv[optind], "start"))
 548         {
 549                 if (fw3_lock())
 550                 {
 551                         rv = start();
 552                         fw3_unlock();
 553                 }
 554         }
 555         else if (!strcmp(argv[optind], "stop"))
 556         {
 557                 if (fw3_lock())
 558                 {
 559                         rv = stop(false);
 560                         fw3_unlock();
 561                 }
 562         }
 563         else if (!strcmp(argv[optind], "flush"))
 564         {
 565                 if (fw3_lock())
 566                 {
 567                         rv = stop(true);
 568                         fw3_unlock();
 569                 }
 570         }
 571         else if (!strcmp(argv[optind], "restart"))
 572         {
 573                 if (fw3_lock())
 574                 {
 575                         stop(true);
 576                         rv = start();
 577                         fw3_unlock();
 578                 }
 579         }
 580         else if (!strcmp(argv[optind], "reload"))
 581         {
 582                 if (fw3_lock())
 583                 {
 584                         rv = reload();
 585                         fw3_unlock();
 586                 }
 587         }
 588         else if (!strcmp(argv[optind], "network") && (optind + 1) < argc)
 589         {
 590                 rv = lookup_network(argv[optind + 1]);
 591         }
 592         else if (!strcmp(argv[optind], "device") && (optind + 1) < argc)
 593         {
 594                 rv = lookup_device(argv[optind + 1]);
 595         }
 596         else
 597         {
 598                 rv = usage();
 599         }
 600
 601 out:
 602         if (cfg_state)
 603                 free_state(cfg_state);
 604
 605         if (run_state)
 606                 free_state(run_state);
 607
 608         return rv;
 609 }