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 = malloc(sizeof(*state));
  49
  50         if (!state)
  51                 error("Out of memory");
  52
  53         memset(state, 0, sizeof(*state));
  54         state->uci = uci_alloc_context();
  55
  56         if (!state->uci)
  57                 error("Out of memory");
  58
  59         if (runtime)
  60         {
  61                 sf = fopen(FW3_STATEFILE, "r");
  62
  63                 if (sf)
  64                 {
  65                         uci_import(state->uci, sf, "fw3_state", &p, true);
  66                         fclose(sf);
  67                 }
  68
  69                 if (!p)
  70                 {
  71                         uci_free_context(state->uci);
  72                         free(state);
  73
  74                         return false;
  75                 }
  76
  77                 state->statefile = true;
  78
  79                 run_state = state;
  80         }
  81         else
  82         {
  83                 if (!fw3_ubus_connect())
  84                         error("Failed to connect to ubus");
  85
  86                 if (uci_load(state->uci, "firewall", &p))
  87                 {
  88                         uci_perror(state->uci, NULL);
  89                         error("Failed to load /etc/config/firewall");
  90                 }
  91
  92                 if (!fw3_find_command("ipset"))
  93                 {
  94                         warn("Unable to locate ipset utility, disabling ipset support");
  95                         state->disable_ipsets = true;
  96                 }
  97
  98                 cfg_state = state;
  99         }
 100
 101         fw3_load_defaults(state, p);
 102         fw3_load_ipsets(state, p);
 103         fw3_load_zones(state, p);
 104         fw3_load_rules(state, p);
 105         fw3_load_redirects(state, p);
 106         fw3_load_snats(state, p);
 107         fw3_load_forwards(state, p);
 108         fw3_load_includes(state, p);
 109
 110         return true;
 111 }
 112
 113 static void
 114 free_state(struct fw3_state *state)
 115 {
 116         struct list_head *cur, *tmp;
 117
 118         list_for_each_safe(cur, tmp, &state->zones)
 119                 fw3_free_zone((struct fw3_zone *)cur);
 120
 121         list_for_each_safe(cur, tmp, &state->rules)
 122                 fw3_free_rule((struct fw3_rule *)cur);
 123
 124         list_for_each_safe(cur, tmp, &state->redirects)
 125                 fw3_free_redirect((struct fw3_redirect *)cur);
 126
 127         list_for_each_safe(cur, tmp, &state->snats)
 128                 fw3_free_snat((struct fw3_snat *)cur);
 129
 130         list_for_each_safe(cur, tmp, &state->forwards)
 131                 fw3_free_forward((struct fw3_forward *)cur);
 132
 133         list_for_each_safe(cur, tmp, &state->ipsets)
 134                 fw3_free_ipset((struct fw3_ipset *)cur);
 135
 136         list_for_each_safe(cur, tmp, &state->includes)
 137                 fw3_free_include((struct fw3_include *)cur);
 138
 139         uci_free_context(state->uci);
 140
 141         free(state);
 142
 143         fw3_ubus_disconnect();
 144 }
 145
 146
 147 static bool
 148 family_running(enum fw3_family family)
 149 {
 150         return (run_state && has(run_state->defaults.flags, family, family));
 151 }
 152
 153 static void
 154 family_set(struct fw3_state *state, enum fw3_family family, bool set)
 155 {
 156         if (!state)
 157                 return;
 158
 159         if (set)
 160                 set(state->defaults.flags, family, family);
 161         else
 162                 del(state->defaults.flags, family, family);
 163 }
 164
 165 static int
 166 stop(bool complete)
 167 {
 168         FILE *ct;
 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 && (ct = fopen("/proc/net/nf_conntrack", "w")) != NULL)
 226         {
 227                 info(" * Flushing conntrack table ...");
 228
 229                 fwrite("f\n", 2, 1, ct);
 230                 fclose(ct);
 231         }
 232
 233         if (!rv && run_state)
 234                 fw3_write_statefile(run_state);
 235
 236         return rv;
 237 }
 238
 239 static int
 240 start(void)
 241 {
 242         int rv = 1;
 243         enum fw3_family family;
 244         enum fw3_table table;
 245         struct fw3_ipt_handle *handle;
 246
 247         if (!print_family)
 248                 fw3_create_ipsets(cfg_state);
 249
 250         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 251         {
 252                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 253                         continue;
 254
 255                 if (print_family && family != print_family)
 256                         continue;
 257
 258                 if (!print_family && family_running(family))
 259                 {
 260                         warn("The %s firewall appears to be started already. "
 261                              "If it is indeed empty, remove the %s file and retry.",
 262                              fw3_flag_names[family], FW3_STATEFILE);
 263
 264                         continue;
 265                 }
 266
 267                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 268                 {
 269                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 270                                 continue;
 271
 272                         if (!(handle = fw3_ipt_open(family, table)))
 273                                 continue;
 274
 275                         info(" * Populating %s %s table",
 276                              fw3_flag_names[family], fw3_flag_names[table]);
 277
 278                         fw3_print_default_chains(handle, cfg_state, false);
 279                         fw3_print_zone_chains(handle, cfg_state, false);
 280                         fw3_print_default_head_rules(handle, cfg_state, false);
 281                         fw3_print_rules(handle, cfg_state);
 282                         fw3_print_redirects(handle, cfg_state);
 283                         fw3_print_snats(handle, cfg_state);
 284                         fw3_print_forwards(handle, cfg_state);
 285                         fw3_print_zone_rules(handle, cfg_state, false);
 286                         fw3_print_default_tail_rules(handle, cfg_state, false);
 287
 288                         if (!print_family)
 289                                 fw3_ipt_commit(handle);
 290
 291                         fw3_ipt_close(handle);
 292                 }
 293
 294                 if (!print_family)
 295                         fw3_print_includes(cfg_state, family, false);
 296
 297                 family_set(run_state, family, true);
 298                 family_set(cfg_state, family, true);
 299
 300                 rv = 0;
 301         }
 302
 303         if (!rv)
 304         {
 305                 fw3_set_defaults(cfg_state);
 306
 307                 if (!print_family)
 308                 {
 309                         fw3_run_includes(cfg_state, false);
 310                         fw3_hotplug_zones(cfg_state, true);
 311                         fw3_write_statefile(cfg_state);
 312                 }
 313         }
 314
 315         return rv;
 316 }
 317
 318
 319 static int
 320 reload(void)
 321 {
 322         int rv = 1;
 323         enum fw3_family family;
 324         enum fw3_table table;
 325         struct fw3_ipt_handle *handle;
 326
 327         if (!run_state)
 328                 return start();
 329
 330         fw3_hotplug_zones(run_state, false);
 331
 332         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 333         {
 334                 if (!family_running(family))
 335                         goto start;
 336
 337                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 338                 {
 339                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 340                                 continue;
 341
 342                         if (!(handle = fw3_ipt_open(family, table)))
 343                                 continue;
 344
 345                         info(" * Clearing %s %s table",
 346                              fw3_flag_names[family], fw3_flag_names[table]);
 347
 348                         fw3_flush_rules(handle, run_state, true);
 349                         fw3_flush_zones(handle, run_state, true);
 350                         fw3_ipt_commit(handle);
 351                         fw3_ipt_close(handle);
 352                 }
 353
 354                 family_set(run_state, family, false);
 355                 family_set(cfg_state, family, false);
 356
 357 start:
 358                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 359                         continue;
 360
 361                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 362                 {
 363                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 364                                 continue;
 365
 366                         if (!(handle = fw3_ipt_open(family, table)))
 367                                 continue;
 368
 369                         info(" * Populating %s %s table",
 370                              fw3_flag_names[family], fw3_flag_names[table]);
 371
 372                         fw3_print_default_chains(handle, cfg_state, true);
 373                         fw3_print_zone_chains(handle, cfg_state, true);
 374                         fw3_print_default_head_rules(handle, cfg_state, true);
 375                         fw3_print_rules(handle, cfg_state);
 376                         fw3_print_redirects(handle, cfg_state);
 377                         fw3_print_forwards(handle, cfg_state);
 378                         fw3_print_zone_rules(handle, cfg_state, true);
 379                         fw3_print_default_tail_rules(handle, cfg_state, true);
 380
 381                         fw3_ipt_commit(handle);
 382                         fw3_ipt_close(handle);
 383                 }
 384
 385                 fw3_print_includes(cfg_state, family, true);
 386
 387                 family_set(run_state, family, true);
 388                 family_set(cfg_state, family, true);
 389
 390                 rv = 0;
 391         }
 392
 393         if (!rv)
 394         {
 395                 fw3_set_defaults(cfg_state);
 396                 fw3_run_includes(cfg_state, true);
 397                 fw3_hotplug_zones(cfg_state, true);
 398                 fw3_write_statefile(cfg_state);
 399         }
 400
 401         return rv;
 402 }
 403
 404 static int
 405 lookup_network(const char *net)
 406 {
 407         struct fw3_zone *z;
 408         struct fw3_device *d;
 409
 410         list_for_each_entry(z, &cfg_state->zones, list)
 411         {
 412                 list_for_each_entry(d, &z->networks, list)
 413                 {
 414                         if (!strcmp(d->name, net))
 415                         {
 416                                 printf("%s\n", z->name);
 417                                 return 0;
 418                         }
 419                 }
 420         }
 421
 422         return 1;
 423 }
 424
 425 static int
 426 lookup_device(const char *dev)
 427 {
 428         struct fw3_zone *z;
 429         struct fw3_device *d;
 430
 431         list_for_each_entry(z, &cfg_state->zones, list)
 432         {
 433                 list_for_each_entry(d, &z->devices, list)
 434                 {
 435                         if (!strcmp(d->name, dev))
 436                         {
 437                                 printf("%s\n", z->name);
 438                                 return 0;
 439                         }
 440                 }
 441         }
 442
 443         return 1;
 444 }
 445
 446 static int
 447 usage(void)
 448 {
 449         fprintf(stderr, "fw3 [-4] [-6] [-q] print\n");
 450         fprintf(stderr, "fw3 [-q] {start|stop|flush|reload|restart}\n");
 451         fprintf(stderr, "fw3 [-q] network {net}\n");
 452         fprintf(stderr, "fw3 [-q] device {dev}\n");
 453
 454         return 1;
 455 }
 456
 457
 458 int main(int argc, char **argv)
 459 {
 460         int ch, rv = 1;
 461         enum fw3_family family = FW3_FAMILY_ANY;
 462         struct fw3_defaults *defs = NULL;
 463
 464         while ((ch = getopt(argc, argv, "46dqh")) != -1)
 465         {
 466                 switch (ch)
 467                 {
 468                 case '4':
 469                         family = FW3_FAMILY_V4;
 470                         break;
 471
 472                 case '6':
 473                         family = FW3_FAMILY_V6;
 474                         break;
 475
 476                 case 'd':
 477                         fw3_pr_debug = true;
 478                         break;
 479
 480                 case 'q':
 481                         freopen("/dev/null", "w", stderr);
 482                         break;
 483
 484                 case 'h':
 485                         rv = usage();
 486                         goto out;
 487                 }
 488         }
 489
 490         build_state(false);
 491         build_state(true);
 492         defs = &cfg_state->defaults;
 493
 494         if (optind >= argc)
 495         {
 496                 rv = usage();
 497                 goto out;
 498         }
 499
 500         if (!strcmp(argv[optind], "print"))
 501         {
 502                 if (family == FW3_FAMILY_ANY)
 503                 {
 504                         family = FW3_FAMILY_V4;
 505                 }
 506                 else if (family == FW3_FAMILY_V6)
 507                 {
 508                         if (defs->disable_ipv6)
 509                                 warn("IPv6 rules globally disabled in configuration");
 510 #ifdef DISABLE_IPV6
 511                         else
 512                                 warn("IPv6 support is not compiled in");
 513 #endif
 514                 }
 515
 516                 freopen("/dev/null", "w", stderr);
 517
 518                 cfg_state->disable_ipsets = true;
 519                 print_family = family;
 520                 fw3_pr_debug = true;
 521
 522                 rv = start();
 523         }
 524         else if (!strcmp(argv[optind], "start"))
 525         {
 526                 if (fw3_lock())
 527                 {
 528                         rv = start();
 529                         fw3_unlock();
 530                 }
 531         }
 532         else if (!strcmp(argv[optind], "stop"))
 533         {
 534                 if (fw3_lock())
 535                 {
 536                         rv = stop(false);
 537                         fw3_unlock();
 538                 }
 539         }
 540         else if (!strcmp(argv[optind], "flush"))
 541         {
 542                 if (fw3_lock())
 543                 {
 544                         rv = stop(true);
 545                         fw3_unlock();
 546                 }
 547         }
 548         else if (!strcmp(argv[optind], "restart"))
 549         {
 550                 if (fw3_lock())
 551                 {
 552                         stop(true);
 553                         rv = start();
 554                         fw3_unlock();
 555                 }
 556         }
 557         else if (!strcmp(argv[optind], "reload"))
 558         {
 559                 if (fw3_lock())
 560                 {
 561                         rv = reload();
 562                         fw3_unlock();
 563                 }
 564         }
 565         else if (!strcmp(argv[optind], "network") && (optind + 1) < argc)
 566         {
 567                 rv = lookup_network(argv[optind + 1]);
 568         }
 569         else if (!strcmp(argv[optind], "device") && (optind + 1) < argc)
 570         {
 571                 rv = lookup_device(argv[optind + 1]);
 572         }
 573         else
 574         {
 575                 rv = usage();
 576         }
 577
 578 out:
 579         if (cfg_state)
 580                 free_state(cfg_state);
 581
 582         if (run_state)
 583                 free_state(run_state);
 584
 585         return rv;
 586 }