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                 }
 209
 210                 family_set(run_state, family, false);
 211                 family_set(cfg_state, family, false);
 212
 213                 rv = 0;
 214         }
 215
 216         if (run_state)
 217                 fw3_destroy_ipsets(run_state);
 218
 219         if (complete && (ct = fopen("/proc/net/nf_conntrack", "w")) != NULL)
 220         {
 221                 info(" * Flushing conntrack table ...");
 222
 223                 fwrite("f\n", 2, 1, ct);
 224                 fclose(ct);
 225         }
 226
 227         if (!rv && run_state)
 228                 fw3_write_statefile(run_state);
 229
 230         return rv;
 231 }
 232
 233 static int
 234 start(void)
 235 {
 236         int rv = 1;
 237         enum fw3_family family;
 238         enum fw3_table table;
 239         struct fw3_ipt_handle *handle;
 240
 241         if (!print_family)
 242                 fw3_create_ipsets(cfg_state);
 243
 244         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 245         {
 246                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 247                         continue;
 248
 249                 if (print_family && family != print_family)
 250                         continue;
 251
 252                 if (!print_family && family_running(family))
 253                 {
 254                         warn("The %s firewall appears to be started already. "
 255                              "If it is indeed empty, remove the %s file and retry.",
 256                              fw3_flag_names[family], FW3_STATEFILE);
 257
 258                         continue;
 259                 }
 260
 261                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 262                 {
 263                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 264                                 continue;
 265
 266                         if (!(handle = fw3_ipt_open(family, table)))
 267                                 continue;
 268
 269                         info(" * Populating %s %s table",
 270                              fw3_flag_names[family], fw3_flag_names[table]);
 271
 272                         fw3_print_default_chains(handle, cfg_state, false);
 273                         fw3_print_zone_chains(handle, cfg_state, false);
 274                         fw3_print_default_head_rules(handle, cfg_state, false);
 275                         fw3_print_rules(handle, cfg_state);
 276                         fw3_print_redirects(handle, cfg_state);
 277                         fw3_print_forwards(handle, cfg_state);
 278                         fw3_print_zone_rules(handle, cfg_state, false);
 279                         fw3_print_default_tail_rules(handle, cfg_state, false);
 280
 281                         if (!print_family)
 282                                 fw3_ipt_commit(handle);
 283                 }
 284
 285                 if (!print_family)
 286                         fw3_print_includes(cfg_state, family, false);
 287
 288                 family_set(run_state, family, true);
 289                 family_set(cfg_state, family, true);
 290
 291                 rv = 0;
 292         }
 293
 294         if (!rv)
 295         {
 296                 fw3_set_defaults(cfg_state);
 297
 298                 if (!print_family)
 299                 {
 300                         fw3_run_includes(cfg_state, false);
 301                         fw3_hotplug_zones(cfg_state, true);
 302                         fw3_write_statefile(cfg_state);
 303                 }
 304         }
 305
 306         return rv;
 307 }
 308
 309
 310 static int
 311 reload(void)
 312 {
 313         int rv = 1;
 314         enum fw3_family family;
 315         enum fw3_table table;
 316         struct fw3_ipt_handle *handle;
 317
 318         if (!run_state)
 319                 return start();
 320
 321         fw3_hotplug_zones(run_state, false);
 322
 323         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 324         {
 325                 if (!family_running(family))
 326                         goto start;
 327
 328                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 329                 {
 330                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 331                                 continue;
 332
 333                         if (!(handle = fw3_ipt_open(family, table)))
 334                                 continue;
 335
 336                         info(" * Clearing %s %s table",
 337                              fw3_flag_names[family], fw3_flag_names[table]);
 338
 339                         fw3_flush_rules(handle, run_state, true);
 340                         fw3_flush_zones(handle, run_state, true);
 341                         fw3_ipt_commit(handle);
 342                 }
 343
 344                 family_set(run_state, family, false);
 345                 family_set(cfg_state, family, false);
 346
 347 start:
 348                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 349                         continue;
 350
 351                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 352                 {
 353                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 354                                 continue;
 355
 356                         if (!(handle = fw3_ipt_open(family, table)))
 357                                 continue;
 358
 359                         info(" * Populating %s %s table",
 360                              fw3_flag_names[family], fw3_flag_names[table]);
 361
 362                         fw3_print_default_chains(handle, cfg_state, true);
 363                         fw3_print_zone_chains(handle, cfg_state, true);
 364                         fw3_print_default_head_rules(handle, cfg_state, true);
 365                         fw3_print_rules(handle, cfg_state);
 366                         fw3_print_redirects(handle, cfg_state);
 367                         fw3_print_forwards(handle, cfg_state);
 368                         fw3_print_zone_rules(handle, cfg_state, true);
 369                         fw3_print_default_tail_rules(handle, cfg_state, true);
 370
 371                         fw3_ipt_commit(handle);
 372                 }
 373
 374                 fw3_print_includes(cfg_state, family, true);
 375
 376                 family_set(run_state, family, true);
 377                 family_set(cfg_state, family, true);
 378
 379                 rv = 0;
 380         }
 381
 382         if (!rv)
 383         {
 384                 fw3_set_defaults(cfg_state);
 385                 fw3_run_includes(cfg_state, true);
 386                 fw3_hotplug_zones(cfg_state, true);
 387                 fw3_write_statefile(cfg_state);
 388         }
 389
 390         return rv;
 391 }
 392
 393 static int
 394 lookup_network(const char *net)
 395 {
 396         struct fw3_zone *z;
 397         struct fw3_device *d;
 398
 399         list_for_each_entry(z, &cfg_state->zones, list)
 400         {
 401                 list_for_each_entry(d, &z->networks, list)
 402                 {
 403                         if (!strcmp(d->name, net))
 404                         {
 405                                 printf("%s\n", z->name);
 406                                 return 0;
 407                         }
 408                 }
 409         }
 410
 411         return 1;
 412 }
 413
 414 static int
 415 lookup_device(const char *dev)
 416 {
 417         struct fw3_zone *z;
 418         struct fw3_device *d;
 419
 420         list_for_each_entry(z, &cfg_state->zones, list)
 421         {
 422                 list_for_each_entry(d, &z->devices, list)
 423                 {
 424                         if (!strcmp(d->name, dev))
 425                         {
 426                                 printf("%s\n", z->name);
 427                                 return 0;
 428                         }
 429                 }
 430         }
 431
 432         return 1;
 433 }
 434
 435 static int
 436 usage(void)
 437 {
 438         fprintf(stderr, "fw3 [-4] [-6] [-q] print\n");
 439         fprintf(stderr, "fw3 [-q] {start|stop|flush|reload|restart}\n");
 440         fprintf(stderr, "fw3 [-q] network {net}\n");
 441         fprintf(stderr, "fw3 [-q] device {dev}\n");
 442
 443         return 1;
 444 }
 445
 446
 447 int main(int argc, char **argv)
 448 {
 449         int ch, rv = 1;
 450         enum fw3_family family = FW3_FAMILY_ANY;
 451         struct fw3_defaults *defs = NULL;
 452
 453         while ((ch = getopt(argc, argv, "46dqh")) != -1)
 454         {
 455                 switch (ch)
 456                 {
 457                 case '4':
 458                         family = FW3_FAMILY_V4;
 459                         break;
 460
 461                 case '6':
 462                         family = FW3_FAMILY_V6;
 463                         break;
 464
 465                 case 'd':
 466                         fw3_pr_debug = true;
 467                         break;
 468
 469                 case 'q':
 470                         freopen("/dev/null", "w", stderr);
 471                         break;
 472
 473                 case 'h':
 474                         rv = usage();
 475                         goto out;
 476                 }
 477         }
 478
 479         build_state(false);
 480         build_state(true);
 481         defs = &cfg_state->defaults;
 482
 483         if (optind >= argc)
 484         {
 485                 rv = usage();
 486                 goto out;
 487         }
 488
 489         if (!strcmp(argv[optind], "print"))
 490         {
 491                 if (family == FW3_FAMILY_ANY)
 492                         family = FW3_FAMILY_V4;
 493                 else if (family == FW3_FAMILY_V6 && defs->disable_ipv6)
 494                         warn("IPv6 rules globally disabled in configuration");
 495
 496                 freopen("/dev/null", "w", stderr);
 497
 498                 cfg_state->disable_ipsets = true;
 499                 print_family = family;
 500                 fw3_pr_debug = true;
 501
 502                 rv = start();
 503         }
 504         else if (!strcmp(argv[optind], "start"))
 505         {
 506                 if (fw3_lock())
 507                 {
 508                         rv = start();
 509                         fw3_unlock();
 510                 }
 511         }
 512         else if (!strcmp(argv[optind], "stop"))
 513         {
 514                 if (fw3_lock())
 515                 {
 516                         rv = stop(false);
 517                         fw3_unlock();
 518                 }
 519         }
 520         else if (!strcmp(argv[optind], "flush"))
 521         {
 522                 if (fw3_lock())
 523                 {
 524                         rv = stop(true);
 525                         fw3_unlock();
 526                 }
 527         }
 528         else if (!strcmp(argv[optind], "restart"))
 529         {
 530                 if (fw3_lock())
 531                 {
 532                         stop(true);
 533                         rv = start();
 534                         fw3_unlock();
 535                 }
 536         }
 537         else if (!strcmp(argv[optind], "reload"))
 538         {
 539                 if (fw3_lock())
 540                 {
 541                         rv = reload();
 542                         fw3_unlock();
 543                 }
 544         }
 545         else if (!strcmp(argv[optind], "network") && (optind + 1) < argc)
 546         {
 547                 rv = lookup_network(argv[optind + 1]);
 548         }
 549         else if (!strcmp(argv[optind], "device") && (optind + 1) < argc)
 550         {
 551                 rv = lookup_device(argv[optind + 1]);
 552         }
 553         else
 554         {
 555                 rv = usage();
 556         }
 557
 558 out:
 559         if (cfg_state)
 560                 free_state(cfg_state);
 561
 562         if (run_state)
 563                 free_state(run_state);
 564
 565         return rv;
 566 }