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 (!print_family && run_state)
 319                 fw3_hotplug_zones(run_state, false);
 320
 321         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 322         {
 323                 if (!family_running(family))
 324                         goto start;
 325
 326                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 327                 {
 328                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 329                                 continue;
 330
 331                         if (!(handle = fw3_ipt_open(family, table)))
 332                                 continue;
 333
 334                         info(" * Clearing %s %s table",
 335                              fw3_flag_names[family], fw3_flag_names[table]);
 336
 337                         if (run_state)
 338                         {
 339                                 fw3_flush_rules(handle, run_state, true);
 340                                 fw3_flush_zones(handle, run_state, true);
 341                         }
 342
 343                         fw3_ipt_commit(handle);
 344                 }
 345
 346                 family_set(run_state, family, false);
 347                 family_set(cfg_state, family, false);
 348
 349 start:
 350                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 351                         continue;
 352
 353                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 354                 {
 355                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 356                                 continue;
 357
 358                         if (!(handle = fw3_ipt_open(family, table)))
 359                                 continue;
 360
 361                         info(" * Populating %s %s table",
 362                              fw3_flag_names[family], fw3_flag_names[table]);
 363
 364                         fw3_print_default_chains(handle, cfg_state, true);
 365                         fw3_print_zone_chains(handle, cfg_state, true);
 366                         fw3_print_default_head_rules(handle, cfg_state, true);
 367                         fw3_print_rules(handle, cfg_state);
 368                         fw3_print_redirects(handle, cfg_state);
 369                         fw3_print_forwards(handle, cfg_state);
 370                         fw3_print_zone_rules(handle, cfg_state, true);
 371                         fw3_print_default_tail_rules(handle, cfg_state, true);
 372
 373                         fw3_ipt_commit(handle);
 374                 }
 375
 376                 fw3_print_includes(cfg_state, family, true);
 377
 378                 family_set(run_state, family, true);
 379                 family_set(cfg_state, family, true);
 380
 381                 rv = 0;
 382         }
 383
 384         if (!rv)
 385         {
 386                 fw3_set_defaults(cfg_state);
 387
 388                 if (!print_family)
 389                 {
 390                         fw3_run_includes(cfg_state, true);
 391                         fw3_hotplug_zones(cfg_state, true);
 392                         fw3_write_statefile(cfg_state);
 393                 }
 394         }
 395
 396         return rv;
 397 }
 398
 399 static int
 400 lookup_network(const char *net)
 401 {
 402         struct fw3_zone *z;
 403         struct fw3_device *d;
 404
 405         list_for_each_entry(z, &cfg_state->zones, list)
 406         {
 407                 list_for_each_entry(d, &z->networks, list)
 408                 {
 409                         if (!strcmp(d->name, net))
 410                         {
 411                                 printf("%s\n", z->name);
 412                                 return 0;
 413                         }
 414                 }
 415         }
 416
 417         return 1;
 418 }
 419
 420 static int
 421 lookup_device(const char *dev)
 422 {
 423         struct fw3_zone *z;
 424         struct fw3_device *d;
 425
 426         list_for_each_entry(z, &cfg_state->zones, list)
 427         {
 428                 list_for_each_entry(d, &z->devices, list)
 429                 {
 430                         if (!strcmp(d->name, dev))
 431                         {
 432                                 printf("%s\n", z->name);
 433                                 return 0;
 434                         }
 435                 }
 436         }
 437
 438         return 1;
 439 }
 440
 441 static int
 442 usage(void)
 443 {
 444         fprintf(stderr, "fw3 [-4] [-6] [-q] print\n");
 445         fprintf(stderr, "fw3 [-q] {start|stop|flush|reload|restart}\n");
 446         fprintf(stderr, "fw3 [-q] network {net}\n");
 447         fprintf(stderr, "fw3 [-q] device {dev}\n");
 448
 449         return 1;
 450 }
 451
 452
 453 int main(int argc, char **argv)
 454 {
 455         int ch, rv = 1;
 456         struct fw3_defaults *defs = NULL;
 457
 458         while ((ch = getopt(argc, argv, "46dqh")) != -1)
 459         {
 460                 switch (ch)
 461                 {
 462                 case '4':
 463                         print_family = FW3_FAMILY_V4;
 464                         break;
 465
 466                 case '6':
 467                         print_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 (print_family == FW3_FAMILY_ANY)
 497                         print_family = FW3_FAMILY_V4;
 498                 else if (print_family == FW3_FAMILY_V6 && defs->disable_ipv6)
 499                         warn("IPv6 rules globally disabled in configuration");
 500
 501                 freopen("/dev/null", "w", stderr);
 502
 503                 cfg_state->disable_ipsets = true;
 504                 fw3_pr_debug = true;
 505
 506                 rv = start();
 507         }
 508         else if (!strcmp(argv[optind], "start"))
 509         {
 510                 if (fw3_lock())
 511                 {
 512                         rv = start();
 513                         fw3_unlock();
 514                 }
 515         }
 516         else if (!strcmp(argv[optind], "stop"))
 517         {
 518                 if (fw3_lock())
 519                 {
 520                         rv = stop(false);
 521                         fw3_unlock();
 522                 }
 523         }
 524         else if (!strcmp(argv[optind], "flush"))
 525         {
 526                 if (fw3_lock())
 527                 {
 528                         rv = stop(true);
 529                         fw3_unlock();
 530                 }
 531         }
 532         else if (!strcmp(argv[optind], "restart"))
 533         {
 534                 if (fw3_lock())
 535                 {
 536                         stop(true);
 537                         rv = start();
 538                         fw3_unlock();
 539                 }
 540         }
 541         else if (!strcmp(argv[optind], "reload"))
 542         {
 543                 if (fw3_lock())
 544                 {
 545                         rv = reload();
 546                         fw3_unlock();
 547                 }
 548         }
 549         else if (!strcmp(argv[optind], "network") && (optind + 1) < argc)
 550         {
 551                 rv = lookup_network(argv[optind + 1]);
 552         }
 553         else if (!strcmp(argv[optind], "device") && (optind + 1) < argc)
 554         {
 555                 rv = lookup_device(argv[optind + 1]);
 556         }
 557         else
 558         {
 559                 rv = usage();
 560         }
 561
 562 out:
 563         if (cfg_state)
 564                 free_state(cfg_state);
 565
 566         if (run_state)
 567                 free_state(run_state);
 568
 569         return rv;
 570 }