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 bool print_rules = false;
  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_rules && 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_rules)
 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_rules && family_running(family))
 262                 {
 263                         warn("The %s firewall appears to be started already. "
 264                              "If it is indeed empty, remove the %s file and retry.",
 265                              fw3_flag_names[family], FW3_STATEFILE);
 266
 267                         continue;
 268                 }
 269
 270                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 271                 {
 272                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 273                                 continue;
 274
 275                         if (!(handle = fw3_ipt_open(family, table)))
 276                                 continue;
 277
 278                         info(" * Populating %s %s table",
 279                              fw3_flag_names[family], fw3_flag_names[table]);
 280
 281                         fw3_print_default_chains(handle, cfg_state, false);
 282                         fw3_print_zone_chains(handle, cfg_state, false);
 283                         fw3_print_default_head_rules(handle, cfg_state, false);
 284                         fw3_print_rules(handle, cfg_state);
 285                         fw3_print_redirects(handle, cfg_state);
 286                         fw3_print_forwards(handle, cfg_state);
 287                         fw3_print_zone_rules(handle, cfg_state, false);
 288                         fw3_print_default_tail_rules(handle, cfg_state, false);
 289
 290                         fw3_ipt_commit(handle);
 291                 }
 292
 293                 //fw3_print_includes(cfg_state, family, false);
 294
 295                 family_set(run_state, family, true);
 296                 family_set(cfg_state, family, true);
 297
 298                 rv = 0;
 299         }
 300
 301         if (!rv)
 302         {
 303                 fw3_set_defaults(cfg_state);
 304
 305                 if (!print_rules)
 306                 {
 307                         fw3_run_includes(cfg_state, false);
 308                         fw3_hotplug_zones(cfg_state, true);
 309                         fw3_write_statefile(cfg_state);
 310                 }
 311         }
 312
 313         return rv;
 314 }
 315
 316
 317 static int
 318 reload(void)
 319 {
 320         int rv = 1;
 321         enum fw3_family family;
 322         enum fw3_table table;
 323         struct fw3_ipt_handle *handle;
 324
 325         if (!print_rules && run_state)
 326                 fw3_hotplug_zones(run_state, false);
 327
 328         for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 329         {
 330                 if (!family_running(family))
 331                         goto start;
 332
 333                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 334                 {
 335                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 336                                 continue;
 337
 338                         if (!(handle = fw3_ipt_open(family, table)))
 339                                 continue;
 340
 341                         info(" * Clearing %s %s table",
 342                              fw3_flag_names[family], fw3_flag_names[table]);
 343
 344                         if (run_state)
 345                         {
 346                                 fw3_flush_rules(handle, run_state, true);
 347                                 fw3_flush_zones(handle, run_state, true);
 348                         }
 349
 350                         fw3_ipt_commit(handle);
 351                 }
 352
 353                 family_set(run_state, family, false);
 354                 family_set(cfg_state, family, false);
 355
 356 start:
 357                 if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 358                         continue;
 359
 360                 for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 361                 {
 362                         if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))
 363                                 continue;
 364
 365                         if (!(handle = fw3_ipt_open(family, table)))
 366                                 continue;
 367
 368                         info(" * Populating %s %s table",
 369                              fw3_flag_names[family], fw3_flag_names[table]);
 370
 371                         fw3_print_default_chains(handle, cfg_state, true);
 372                         fw3_print_zone_chains(handle, cfg_state, true);
 373                         fw3_print_default_head_rules(handle, cfg_state, true);
 374                         fw3_print_rules(handle, cfg_state);
 375                         fw3_print_redirects(handle, cfg_state);
 376                         fw3_print_forwards(handle, cfg_state);
 377                         fw3_print_zone_rules(handle, cfg_state, true);
 378                         fw3_print_default_tail_rules(handle, cfg_state, true);
 379
 380                         fw3_ipt_commit(handle);
 381                 }
 382
 383                 //fw3_print_includes(cfg_state, family, true);
 384
 385                 family_set(run_state, family, true);
 386                 family_set(cfg_state, family, true);
 387
 388                 rv = 0;
 389         }
 390
 391         if (!rv)
 392         {
 393                 fw3_set_defaults(cfg_state);
 394
 395                 if (!print_rules)
 396                 {
 397                         fw3_run_includes(cfg_state, true);
 398                         fw3_hotplug_zones(cfg_state, true);
 399                         fw3_write_statefile(cfg_state);
 400                 }
 401         }
 402
 403         return rv;
 404 }
 405
 406 static int
 407 lookup_network(const char *net)
 408 {
 409         struct fw3_zone *z;
 410         struct fw3_device *d;
 411
 412         list_for_each_entry(z, &cfg_state->zones, list)
 413         {
 414                 list_for_each_entry(d, &z->networks, list)
 415                 {
 416                         if (!strcmp(d->name, net))
 417                         {
 418                                 printf("%s\n", z->name);
 419                                 return 0;
 420                         }
 421                 }
 422         }
 423
 424         return 1;
 425 }
 426
 427 static int
 428 lookup_device(const char *dev)
 429 {
 430         struct fw3_zone *z;
 431         struct fw3_device *d;
 432
 433         list_for_each_entry(z, &cfg_state->zones, list)
 434         {
 435                 list_for_each_entry(d, &z->devices, list)
 436                 {
 437                         if (!strcmp(d->name, dev))
 438                         {
 439                                 printf("%s\n", z->name);
 440                                 return 0;
 441                         }
 442                 }
 443         }
 444
 445         return 1;
 446 }
 447
 448 static int
 449 usage(void)
 450 {
 451         fprintf(stderr, "fw3 [-4] [-6] [-q] print\n");
 452         fprintf(stderr, "fw3 [-q] {start|stop|flush|reload|restart}\n");
 453         fprintf(stderr, "fw3 [-q] network {net}\n");
 454         fprintf(stderr, "fw3 [-q] device {dev}\n");
 455
 456         return 1;
 457 }
 458
 459
 460 int main(int argc, char **argv)
 461 {
 462         int ch, rv = 1;
 463         struct fw3_defaults *defs = NULL;
 464         enum fw3_family use_family = FW3_FAMILY_ANY;
 465
 466         while ((ch = getopt(argc, argv, "46dqh")) != -1)
 467         {
 468                 switch (ch)
 469                 {
 470                 case '4':
 471                         use_family = FW3_FAMILY_V4;
 472                         break;
 473
 474                 case '6':
 475                         use_family = FW3_FAMILY_V6;
 476                         break;
 477
 478                 case 'd':
 479                         fw3_pr_debug = true;
 480                         break;
 481
 482                 case 'q':
 483                         freopen("/dev/null", "w", stderr);
 484                         break;
 485
 486                 case 'h':
 487                         rv = usage();
 488                         goto out;
 489                 }
 490         }
 491
 492         build_state(false);
 493         build_state(true);
 494         defs = &cfg_state->defaults;
 495
 496         if (optind >= argc)
 497         {
 498                 rv = usage();
 499                 goto out;
 500         }
 501
 502         if (!strcmp(argv[optind], "print"))
 503         {
 504                 if (use_family == FW3_FAMILY_ANY)
 505                         use_family = FW3_FAMILY_V4;
 506                 else if (use_family == FW3_FAMILY_V6 && defs->disable_ipv6)
 507                         warn("IPv6 rules globally disabled in configuration");
 508
 509                 freopen("/dev/null", "w", stderr);
 510
 511                 cfg_state->disable_ipsets = true;
 512                 print_rules = true;
 513
 514                 rv = start();
 515         }
 516         else if (!strcmp(argv[optind], "start"))
 517         {
 518                 if (fw3_lock())
 519                 {
 520                         rv = start();
 521                         fw3_unlock();
 522                 }
 523         }
 524         else if (!strcmp(argv[optind], "stop"))
 525         {
 526                 if (fw3_lock())
 527                 {
 528                         rv = stop(false);
 529                         fw3_unlock();
 530                 }
 531         }
 532         else if (!strcmp(argv[optind], "flush"))
 533         {
 534                 if (fw3_lock())
 535                 {
 536                         rv = stop(true);
 537                         fw3_unlock();
 538                 }
 539         }
 540         else if (!strcmp(argv[optind], "restart"))
 541         {
 542                 if (fw3_lock())
 543                 {
 544                         stop(true);
 545                         rv = start();
 546                         fw3_unlock();
 547                 }
 548         }
 549         else if (!strcmp(argv[optind], "reload"))
 550         {
 551                 if (fw3_lock())
 552                 {
 553                         rv = reload();
 554                         fw3_unlock();
 555                 }
 556         }
 557         else if (!strcmp(argv[optind], "network") && (optind + 1) < argc)
 558         {
 559                 rv = lookup_network(argv[optind + 1]);
 560         }
 561         else if (!strcmp(argv[optind], "device") && (optind + 1) < argc)
 562         {
 563                 rv = lookup_device(argv[optind + 1]);
 564         }
 565         else
 566         {
 567                 rv = usage();
 568         }
 569
 570 out:
 571         if (cfg_state)
 572                 free_state(cfg_state);
 573
 574         if (run_state)
 575                 free_state(run_state);
 576
 577         return rv;
 578 }