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         {
 218                 if (fw3_command_pipe(false, "ipset", "-exist", "-"))
 219                 {
 220                         fw3_destroy_ipsets(run_state);
 221                         fw3_command_close();
 222                 }
 223         }
 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         {
 249                 if (fw3_command_pipe(false, "ipset", "-exist", "-"))
 250                 {
 251                         fw3_create_ipsets(cfg_state);
 252                         fw3_command_close();
 253                 }
 254         }
 255
 256         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 257         {
 258                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 259                         continue;
 260
 261                 if (print_family && family != print_family)
 262                         continue;
 263
 264                 if (!print_family && family_running(family))
 265                 {
 266                         warn("The %s firewall appears to be started already. "
 267                              "If it is indeed empty, remove the %s file and retry.",
 268                              fw3_flag_names[family], FW3_STATEFILE);
 269
 270                         continue;
 271                 }
 272
 273                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 274                 {
 275                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 276                                 continue;
 277
 278                         if (!(handle = fw3_ipt_open(family, table)))
 279                                 continue;
 280
 281                         info(" * Populating %s %s table",
 282                              fw3_flag_names[family], fw3_flag_names[table]);
 283
 284                         fw3_print_default_chains(handle, cfg_state, false);
 285                         fw3_print_zone_chains(handle, cfg_state, false);
 286                         fw3_print_default_head_rules(handle, cfg_state, false);
 287                         fw3_print_rules(handle, cfg_state);
 288                         fw3_print_redirects(handle, cfg_state);
 289                         fw3_print_forwards(handle, cfg_state);
 290                         fw3_print_zone_rules(handle, cfg_state, false);
 291                         fw3_print_default_tail_rules(handle, cfg_state, false);
 292
 293                         if (!print_family)
 294                                 fw3_ipt_commit(handle);
 295                 }
 296
 297                 if (!print_family)
 298                         fw3_print_includes(cfg_state, family, false);
 299
 300                 family_set(run_state, family, true);
 301                 family_set(cfg_state, family, true);
 302
 303                 rv = 0;
 304         }
 305
 306         if (!rv)
 307         {
 308                 fw3_set_defaults(cfg_state);
 309
 310                 if (!print_family)
 311                 {
 312                         fw3_run_includes(cfg_state, false);
 313                         fw3_hotplug_zones(cfg_state, true);
 314                         fw3_write_statefile(cfg_state);
 315                 }
 316         }
 317
 318         return rv;
 319 }
 320
 321
 322 static int
 323 reload(void)
 324 {
 325         int rv = 1;
 326         enum fw3_family family;
 327         enum fw3_table table;
 328         struct fw3_ipt_handle *handle;
 329
 330         if (!print_family && run_state)
 331                 fw3_hotplug_zones(run_state, false);
 332
 333         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 334         {
 335                 if (!family_running(family))
 336                         goto start;
 337
 338                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 339                 {
 340                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 341                                 continue;
 342
 343                         if (!(handle = fw3_ipt_open(family, table)))
 344                                 continue;
 345
 346                         info(" * Clearing %s %s table",
 347                              fw3_flag_names[family], fw3_flag_names[table]);
 348
 349                         if (run_state)
 350                         {
 351                                 fw3_flush_rules(handle, run_state, true);
 352                                 fw3_flush_zones(handle, run_state, true);
 353                         }
 354
 355                         fw3_ipt_commit(handle);
 356                 }
 357
 358                 family_set(run_state, family, false);
 359                 family_set(cfg_state, family, false);
 360
 361 start:
 362                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 363                         continue;
 364
 365                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 366                 {
 367                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 368                                 continue;
 369
 370                         if (!(handle = fw3_ipt_open(family, table)))
 371                                 continue;
 372
 373                         info(" * Populating %s %s table",
 374                              fw3_flag_names[family], fw3_flag_names[table]);
 375
 376                         fw3_print_default_chains(handle, cfg_state, true);
 377                         fw3_print_zone_chains(handle, cfg_state, true);
 378                         fw3_print_default_head_rules(handle, cfg_state, true);
 379                         fw3_print_rules(handle, cfg_state);
 380                         fw3_print_redirects(handle, cfg_state);
 381                         fw3_print_forwards(handle, cfg_state);
 382                         fw3_print_zone_rules(handle, cfg_state, true);
 383                         fw3_print_default_tail_rules(handle, cfg_state, true);
 384
 385                         fw3_ipt_commit(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
 400                 if (!print_family)
 401                 {
 402                         fw3_run_includes(cfg_state, true);
 403                         fw3_hotplug_zones(cfg_state, true);
 404                         fw3_write_statefile(cfg_state);
 405                 }
 406         }
 407
 408         return rv;
 409 }
 410
 411 static int
 412 lookup_network(const char *net)
 413 {
 414         struct fw3_zone *z;
 415         struct fw3_device *d;
 416
 417         list_for_each_entry(z, &cfg_state->zones, list)
 418         {
 419                 list_for_each_entry(d, &z->networks, list)
 420                 {
 421                         if (!strcmp(d->name, net))
 422                         {
 423                                 printf("%s\n", z->name);
 424                                 return 0;
 425                         }
 426                 }
 427         }
 428
 429         return 1;
 430 }
 431
 432 static int
 433 lookup_device(const char *dev)
 434 {
 435         struct fw3_zone *z;
 436         struct fw3_device *d;
 437
 438         list_for_each_entry(z, &cfg_state->zones, list)
 439         {
 440                 list_for_each_entry(d, &z->devices, list)
 441                 {
 442                         if (!strcmp(d->name, dev))
 443                         {
 444                                 printf("%s\n", z->name);
 445                                 return 0;
 446                         }
 447                 }
 448         }
 449
 450         return 1;
 451 }
 452
 453 static int
 454 usage(void)
 455 {
 456         fprintf(stderr, "fw3 [-4] [-6] [-q] print\n");
 457         fprintf(stderr, "fw3 [-q] {start|stop|flush|reload|restart}\n");
 458         fprintf(stderr, "fw3 [-q] network {net}\n");
 459         fprintf(stderr, "fw3 [-q] device {dev}\n");
 460
 461         return 1;
 462 }
 463
 464
 465 int main(int argc, char **argv)
 466 {
 467         int ch, rv = 1;
 468         struct fw3_defaults *defs = NULL;
 469
 470         while ((ch = getopt(argc, argv, "46dqh")) != -1)
 471         {
 472                 switch (ch)
 473                 {
 474                 case '4':
 475                         print_family = FW3_FAMILY_V4;
 476                         break;
 477
 478                 case '6':
 479                         print_family = FW3_FAMILY_V6;
 480                         break;
 481
 482                 case 'd':
 483                         fw3_pr_debug = true;
 484                         break;
 485
 486                 case 'q':
 487                         freopen("/dev/null", "w", stderr);
 488                         break;
 489
 490                 case 'h':
 491                         rv = usage();
 492                         goto out;
 493                 }
 494         }
 495
 496         build_state(false);
 497         build_state(true);
 498         defs = &cfg_state->defaults;
 499
 500         if (optind >= argc)
 501         {
 502                 rv = usage();
 503                 goto out;
 504         }
 505
 506         if (!strcmp(argv[optind], "print"))
 507         {
 508                 if (print_family == FW3_FAMILY_ANY)
 509                         print_family = FW3_FAMILY_V4;
 510                 else if (print_family == FW3_FAMILY_V6 && defs->disable_ipv6)
 511                         warn("IPv6 rules globally disabled in configuration");
 512
 513                 freopen("/dev/null", "w", stderr);
 514
 515                 cfg_state->disable_ipsets = true;
 516                 fw3_pr_debug = true;
 517
 518                 rv = start();
 519         }
 520         else if (!strcmp(argv[optind], "start"))
 521         {
 522                 if (fw3_lock())
 523                 {
 524                         rv = start();
 525                         fw3_unlock();
 526                 }
 527         }
 528         else if (!strcmp(argv[optind], "stop"))
 529         {
 530                 if (fw3_lock())
 531                 {
 532                         rv = stop(false);
 533                         fw3_unlock();
 534                 }
 535         }
 536         else if (!strcmp(argv[optind], "flush"))
 537         {
 538                 if (fw3_lock())
 539                 {
 540                         rv = stop(true);
 541                         fw3_unlock();
 542                 }
 543         }
 544         else if (!strcmp(argv[optind], "restart"))
 545         {
 546                 if (fw3_lock())
 547                 {
 548                         stop(true);
 549                         rv = start();
 550                         fw3_unlock();
 551                 }
 552         }
 553         else if (!strcmp(argv[optind], "reload"))
 554         {
 555                 if (fw3_lock())
 556                 {
 557                         rv = reload();
 558                         fw3_unlock();
 559                 }
 560         }
 561         else if (!strcmp(argv[optind], "network") && (optind + 1) < argc)
 562         {
 563                 rv = lookup_network(argv[optind + 1]);
 564         }
 565         else if (!strcmp(argv[optind], "device") && (optind + 1) < argc)
 566         {
 567                 rv = lookup_device(argv[optind + 1]);
 568         }
 569         else
 570         {
 571                 rv = usage();
 572         }
 573
 574 out:
 575         if (cfg_state)
 576                 free_state(cfg_state);
 577
 578         if (run_state)
 579                 free_state(run_state);
 580
 581         return rv;
 582 }