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 #include "iptables.h"
  32
  33
  34 static enum fw3_family print_family = FW3_FAMILY_ANY;
  35
  36 static struct fw3_state *run_state = NULL;
  37 static struct fw3_state *cfg_state = NULL;
  38
  39
  40 static bool
  41 build_state(bool runtime)
  42 {
  43         struct fw3_state *state = NULL;
  44         struct uci_package *p = NULL;
  45         FILE *sf;
  46
  47         state = malloc(sizeof(*state));
  48
  49         if (!state)
  50                 error("Out of memory");
  51
  52         memset(state, 0, sizeof(*state));
  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                         error("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         fw3_load_defaults(state, p);
 101         fw3_load_ipsets(state, p);
 102         fw3_load_zones(state, p);
 103         fw3_load_rules(state, p);
 104         fw3_load_redirects(state, p);
 105         fw3_load_forwards(state, p);
 106         fw3_load_includes(state, p);
 107
 108         return true;
 109 }
 110
 111 static void
 112 free_state(struct fw3_state *state)
 113 {
 114         struct list_head *cur, *tmp;
 115
 116         list_for_each_safe(cur, tmp, &state->zones)
 117                 fw3_free_zone((struct fw3_zone *)cur);
 118
 119         list_for_each_safe(cur, tmp, &state->rules)
 120                 fw3_free_rule((struct fw3_rule *)cur);
 121
 122         list_for_each_safe(cur, tmp, &state->redirects)
 123                 fw3_free_redirect((struct fw3_redirect *)cur);
 124
 125         list_for_each_safe(cur, tmp, &state->forwards)
 126                 fw3_free_forward((struct fw3_forward *)cur);
 127
 128         list_for_each_safe(cur, tmp, &state->ipsets)
 129                 fw3_free_ipset((struct fw3_ipset *)cur);
 130
 131         list_for_each_safe(cur, tmp, &state->includes)
 132                 fw3_free_include((struct fw3_include *)cur);
 133
 134         uci_free_context(state->uci);
 135
 136         free(state);
 137
 138         fw3_ubus_disconnect();
 139 }
 140
 141
 142 static bool
 143 family_running(enum fw3_family family)
 144 {
 145         return (run_state && has(run_state->defaults.flags, family, family));
 146 }
 147
 148 static void
 149 family_set(struct fw3_state *state, enum fw3_family family, bool set)
 150 {
 151         if (!state)
 152                 return;
 153
 154         if (set)
 155                 set(state->defaults.flags, family, family);
 156         else
 157                 del(state->defaults.flags, family, family);
 158 }
 159
 160 static int
 161 stop(bool complete)
 162 {
 163         FILE *ct;
 164
 165         int rv = 1;
 166         enum fw3_family family;
 167         enum fw3_table table;
 168         struct fw3_ipt_handle *handle;
 169
 170         if (!complete && !run_state)
 171         {
 172                 warn("The firewall appears to be stopped. "
 173                          "Use the 'flush' command to forcefully purge all rules.");
 174
 175                 return rv;
 176         }
 177
 178         if (!print_family && run_state)
 179                 fw3_hotplug_zones(run_state, false);
 180
 181         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 182         {
 183                 if (!complete && !family_running(family))
 184                         continue;
 185
 186                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 187                 {
 188                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 189                                 continue;
 190
 191                         if (!(handle = fw3_ipt_open(family, table)))
 192                                 continue;
 193
 194                         info(" * %sing %s %s table", complete ? "Flush" : "Clear",
 195                              fw3_flag_names[family], fw3_flag_names[table]);
 196
 197                         if (complete)
 198                         {
 199                                 fw3_flush_all(handle);
 200                         }
 201                         else if (run_state)
 202                         {
 203                                 fw3_flush_rules(handle, run_state, false);
 204                                 fw3_flush_zones(handle, run_state, false);
 205                         }
 206
 207                         fw3_ipt_commit(handle);
 208                         fw3_ipt_close(handle);
 209                 }
 210
 211                 family_set(run_state, family, false);
 212                 family_set(cfg_state, family, false);
 213
 214                 rv = 0;
 215         }
 216
 217         if (run_state)
 218                 fw3_destroy_ipsets(run_state);
 219
 220         if (complete && (ct = fopen("/proc/net/nf_conntrack", "w")) != NULL)
 221         {
 222                 info(" * Flushing conntrack table ...");
 223
 224                 fwrite("f\n", 2, 1, ct);
 225                 fclose(ct);
 226         }
 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_forwards(handle, cfg_state);
 279                         fw3_print_zone_rules(handle, cfg_state, false);
 280                         fw3_print_default_tail_rules(handle, cfg_state, false);
 281
 282                         if (!print_family)
 283                                 fw3_ipt_commit(handle);
 284
 285                         fw3_ipt_close(handle);
 286                 }
 287
 288                 if (!print_family)
 289                         fw3_print_includes(cfg_state, family, false);
 290
 291                 family_set(run_state, family, true);
 292                 family_set(cfg_state, family, true);
 293
 294                 rv = 0;
 295         }
 296
 297         if (!rv)
 298         {
 299                 fw3_set_defaults(cfg_state);
 300
 301                 if (!print_family)
 302                 {
 303                         fw3_run_includes(cfg_state, false);
 304                         fw3_hotplug_zones(cfg_state, true);
 305                         fw3_write_statefile(cfg_state);
 306                 }
 307         }
 308
 309         return rv;
 310 }
 311
 312
 313 static int
 314 reload(void)
 315 {
 316         int rv = 1;
 317         enum fw3_family family;
 318         enum fw3_table table;
 319         struct fw3_ipt_handle *handle;
 320
 321         if (!run_state)
 322                 return start();
 323
 324         fw3_hotplug_zones(run_state, false);
 325
 326         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 327         {
 328                 if (!family_running(family))
 329                         goto start;
 330
 331                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 332                 {
 333                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 334                                 continue;
 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                 family_set(run_state, family, false);
 349                 family_set(cfg_state, family, false);
 350
 351 start:
 352                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 353                         continue;
 354
 355                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 356                 {
 357                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 358                                 continue;
 359
 360                         if (!(handle = fw3_ipt_open(family, table)))
 361                                 continue;
 362
 363                         info(" * Populating %s %s table",
 364                              fw3_flag_names[family], fw3_flag_names[table]);
 365
 366                         fw3_print_default_chains(handle, cfg_state, true);
 367                         fw3_print_zone_chains(handle, cfg_state, true);
 368                         fw3_print_default_head_rules(handle, cfg_state, true);
 369                         fw3_print_rules(handle, cfg_state);
 370                         fw3_print_redirects(handle, cfg_state);
 371                         fw3_print_forwards(handle, cfg_state);
 372                         fw3_print_zone_rules(handle, cfg_state, true);
 373                         fw3_print_default_tail_rules(handle, cfg_state, true);
 374
 375                         fw3_ipt_commit(handle);
 376                         fw3_ipt_close(handle);
 377                 }
 378
 379                 fw3_print_includes(cfg_state, family, true);
 380
 381                 family_set(run_state, family, true);
 382                 family_set(cfg_state, family, true);
 383
 384                 rv = 0;
 385         }
 386
 387         if (!rv)
 388         {
 389                 fw3_set_defaults(cfg_state);
 390                 fw3_run_includes(cfg_state, true);
 391                 fw3_hotplug_zones(cfg_state, true);
 392                 fw3_write_statefile(cfg_state);
 393         }
 394
 395         return rv;
 396 }
 397
 398 static int
 399 lookup_network(const char *net)
 400 {
 401         struct fw3_zone *z;
 402         struct fw3_device *d;
 403
 404         list_for_each_entry(z, &cfg_state->zones, list)
 405         {
 406                 list_for_each_entry(d, &z->networks, list)
 407                 {
 408                         if (!strcmp(d->name, net))
 409                         {
 410                                 printf("%s\n", z->name);
 411                                 return 0;
 412                         }
 413                 }
 414         }
 415
 416         return 1;
 417 }
 418
 419 static int
 420 lookup_device(const char *dev)
 421 {
 422         struct fw3_zone *z;
 423         struct fw3_device *d;
 424
 425         list_for_each_entry(z, &cfg_state->zones, list)
 426         {
 427                 list_for_each_entry(d, &z->devices, list)
 428                 {
 429                         if (!strcmp(d->name, dev))
 430                         {
 431                                 printf("%s\n", z->name);
 432                                 return 0;
 433                         }
 434                 }
 435         }
 436
 437         return 1;
 438 }
 439
 440 static int
 441 usage(void)
 442 {
 443         fprintf(stderr, "fw3 [-4] [-6] [-q] print\n");
 444         fprintf(stderr, "fw3 [-q] {start|stop|flush|reload|restart}\n");
 445         fprintf(stderr, "fw3 [-q] network {net}\n");
 446         fprintf(stderr, "fw3 [-q] device {dev}\n");
 447
 448         return 1;
 449 }
 450
 451
 452 int main(int argc, char **argv)
 453 {
 454         int ch, rv = 1;
 455         enum fw3_family family = FW3_FAMILY_ANY;
 456         struct fw3_defaults *defs = NULL;
 457
 458         while ((ch = getopt(argc, argv, "46dqh")) != -1)
 459         {
 460                 switch (ch)
 461                 {
 462                 case '4':
 463                         family = FW3_FAMILY_V4;
 464                         break;
 465
 466                 case '6':
 467                         family = FW3_FAMILY_V6;
 468                         break;
 469
 470                 case 'd':
 471                         fw3_pr_debug = true;
 472                         break;
 473
 474                 case 'q':
 475                         freopen("/dev/null", "w", stderr);
 476                         break;
 477
 478                 case 'h':
 479                         rv = usage();
 480                         goto out;
 481                 }
 482         }
 483
 484         build_state(false);
 485         build_state(true);
 486         defs = &cfg_state->defaults;
 487
 488         if (optind >= argc)
 489         {
 490                 rv = usage();
 491                 goto out;
 492         }
 493
 494         if (!strcmp(argv[optind], "print"))
 495         {
 496                 if (family == FW3_FAMILY_ANY)
 497                 {
 498                         family = FW3_FAMILY_V4;
 499                 }
 500                 else if (family == FW3_FAMILY_V6)
 501                 {
 502                         if (defs->disable_ipv6)
 503                                 warn("IPv6 rules globally disabled in configuration");
 504 #ifdef DISABLE_IPV6
 505                         else
 506                                 warn("IPv6 support is not compiled in");
 507 #endif
 508                 }
 509
 510                 freopen("/dev/null", "w", stderr);
 511
 512                 cfg_state->disable_ipsets = true;
 513                 print_family = family;
 514                 fw3_pr_debug = true;
 515
 516                 rv = start();
 517         }
 518         else if (!strcmp(argv[optind], "start"))
 519         {
 520                 if (fw3_lock())
 521                 {
 522                         rv = start();
 523                         fw3_unlock();
 524                 }
 525         }
 526         else if (!strcmp(argv[optind], "stop"))
 527         {
 528                 if (fw3_lock())
 529                 {
 530                         rv = stop(false);
 531                         fw3_unlock();
 532                 }
 533         }
 534         else if (!strcmp(argv[optind], "flush"))
 535         {
 536                 if (fw3_lock())
 537                 {
 538                         rv = stop(true);
 539                         fw3_unlock();
 540                 }
 541         }
 542         else if (!strcmp(argv[optind], "restart"))
 543         {
 544                 if (fw3_lock())
 545                 {
 546                         stop(true);
 547                         rv = start();
 548                         fw3_unlock();
 549                 }
 550         }
 551         else if (!strcmp(argv[optind], "reload"))
 552         {
 553                 if (fw3_lock())
 554                 {
 555                         rv = reload();
 556                         fw3_unlock();
 557                 }
 558         }
 559         else if (!strcmp(argv[optind], "network") && (optind + 1) < argc)
 560         {
 561                 rv = lookup_network(argv[optind + 1]);
 562         }
 563         else if (!strcmp(argv[optind], "device") && (optind + 1) < argc)
 564         {
 565                 rv = lookup_device(argv[optind + 1]);
 566         }
 567         else
 568         {
 569                 rv = usage();
 570         }
 571
 572 out:
 573         if (cfg_state)
 574                 free_state(cfg_state);
 575
 576         if (run_state)
 577                 free_state(run_state);
 578
 579         return rv;
 580 }