zones.c

   1 /*
   2  * firewall3 - 3rd OpenWrt UCI firewall implementation
   3  *
   4  *   Copyright (C) 2013 Jo-Philipp Wich <jo@mein.io>
   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 "zones.h"
  20 #include "ubus.h"
  21 #include "helpers.h"
  22
  23
  24 #define C(f, tbl, tgt, fmt) \
  25         { FW3_FAMILY_##f, FW3_TABLE_##tbl, FW3_FLAG_##tgt, fmt }
  26
  27 static const struct fw3_chain_spec zone_chains[] = {
  28         C(ANY, FILTER, UNSPEC,        "zone_%s_input"),
  29         C(ANY, FILTER, UNSPEC,        "zone_%s_output"),
  30         C(ANY, FILTER, UNSPEC,        "zone_%s_forward"),
  31
  32         C(ANY, FILTER, SRC_ACCEPT,    "zone_%s_src_ACCEPT"),
  33         C(ANY, FILTER, SRC_REJECT,    "zone_%s_src_REJECT"),
  34         C(ANY, FILTER, SRC_DROP,      "zone_%s_src_DROP"),
  35
  36         C(ANY, FILTER, ACCEPT,        "zone_%s_dest_ACCEPT"),
  37         C(ANY, FILTER, REJECT,        "zone_%s_dest_REJECT"),
  38         C(ANY, FILTER, DROP,          "zone_%s_dest_DROP"),
  39
  40         C(V4,  NAT,    SNAT,          "zone_%s_postrouting"),
  41         C(V4,  NAT,    DNAT,          "zone_%s_prerouting"),
  42
  43         C(ANY, RAW,    HELPER,        "zone_%s_helper"),
  44         C(ANY, RAW,    NOTRACK,       "zone_%s_notrack"),
  45
  46         C(ANY, FILTER, CUSTOM_CHAINS, "input_%s_rule"),
  47         C(ANY, FILTER, CUSTOM_CHAINS, "output_%s_rule"),
  48         C(ANY, FILTER, CUSTOM_CHAINS, "forwarding_%s_rule"),
  49
  50         C(V4,  NAT,    CUSTOM_CHAINS, "prerouting_%s_rule"),
  51         C(V4,  NAT,    CUSTOM_CHAINS, "postrouting_%s_rule"),
  52
  53         { }
  54 };
  55
  56 enum fw3_zone_logmask {
  57         FW3_ZONE_LOG_FILTER = (1 << 0),
  58         FW3_ZONE_LOG_MANGLE = (1 << 1),
  59 };
  60
  61 const struct fw3_option fw3_zone_opts[] = {
  62         FW3_OPT("enabled",             bool,     zone,     enabled),
  63
  64         FW3_OPT("name",                string,   zone,     name),
  65         FW3_OPT("family",              family,   zone,     family),
  66
  67         FW3_LIST("network",            device,   zone,     networks),
  68         FW3_LIST("device",             device,   zone,     devices),
  69         FW3_LIST("subnet",             network,  zone,     subnets),
  70
  71         FW3_OPT("input",               target,   zone,     policy_input),
  72         FW3_OPT("forward",             target,   zone,     policy_forward),
  73         FW3_OPT("output",              target,   zone,     policy_output),
  74
  75         FW3_OPT("masq",                bool,     zone,     masq),
  76         FW3_OPT("masq_allow_invalid",  bool,     zone,     masq_allow_invalid),
  77         FW3_LIST("masq_src",           network,  zone,     masq_src),
  78         FW3_LIST("masq_dest",          network,  zone,     masq_dest),
  79
  80         FW3_OPT("extra",               string,   zone,     extra_src),
  81         FW3_OPT("extra_src",           string,   zone,     extra_src),
  82         FW3_OPT("extra_dest",          string,   zone,     extra_dest),
  83
  84         FW3_OPT("mtu_fix",             bool,     zone,     mtu_fix),
  85         FW3_OPT("custom_chains",       bool,     zone,     custom_chains),
  86
  87         FW3_OPT("log",                 int,      zone,     log),
  88         FW3_OPT("log_limit",           limit,    zone,     log_limit),
  89
  90         FW3_OPT("auto_helper",         bool,     zone,     auto_helper),
  91         FW3_LIST("helper",             cthelper, zone,     cthelpers),
  92
  93         FW3_OPT("__flags_v4",          int,      zone,     flags[0]),
  94         FW3_OPT("__flags_v6",          int,      zone,     flags[1]),
  95
  96         FW3_LIST("__addrs",            address,  zone,     old_addrs),
  97
  98         { }
  99 };
 100
 101
 102 static void
 103 check_policy(struct uci_element *e, enum fw3_flag *pol, enum fw3_flag def,
 104              const char *name)
 105 {
 106         if (*pol == FW3_FLAG_UNSPEC)
 107         {
 108                 warn_elem(e, "has no %s policy specified, using default", name);
 109                 *pol = def;
 110         }
 111         else if (*pol > FW3_FLAG_DROP)
 112         {
 113                 warn_elem(e, "has invalid %s policy, using default", name);
 114                 *pol = def;
 115         }
 116 }
 117
 118 static bool
 119 check_masq_addrs(struct list_head *head)
 120 {
 121         struct fw3_address *addr;
 122         int n_addr = 0, n_failed = 0;
 123
 124         list_for_each_entry(addr, head, list)
 125         {
 126                 if (addr->invert)
 127                         continue;
 128
 129                 n_addr++;
 130
 131                 if (!addr->set && addr->resolved)
 132                         n_failed++;
 133         }
 134
 135         return (n_addr == 0 || n_failed < n_addr);
 136 }
 137
 138 static void
 139 resolve_networks(struct uci_element *e, struct fw3_zone *zone)
 140 {
 141         struct fw3_device *net, *tmp;
 142
 143         list_for_each_entry(net, &zone->networks, list)
 144         {
 145                 tmp = fw3_ubus_device(net->name);
 146
 147                 if (!tmp)
 148                 {
 149                         warn_elem(e, "cannot resolve device of network '%s'", net->name);
 150                         continue;
 151                 }
 152
 153                 snprintf(tmp->network, sizeof(tmp->network), "%s", net->name);
 154                 list_add_tail(&tmp->list, &zone->devices);
 155         }
 156 }
 157
 158 static void
 159 resolve_cthelpers(struct fw3_state *s, struct uci_element *e, struct fw3_zone *zone)
 160 {
 161         struct fw3_cthelpermatch *match;
 162
 163         if (list_empty(&zone->cthelpers))
 164         {
 165                 if (!zone->masq && zone->auto_helper)
 166                 {
 167                         fw3_setbit(zone->flags[0], FW3_FLAG_HELPER);
 168                         fw3_setbit(zone->flags[1], FW3_FLAG_HELPER);
 169                 }
 170
 171                 return;
 172         }
 173
 174         list_for_each_entry(match, &zone->cthelpers, list)
 175         {
 176                 if (match->invert)
 177                 {
 178                         warn_elem(e, "must not use a negated helper match");
 179                         continue;
 180                 }
 181
 182                 match->ptr = fw3_lookup_cthelper(s, match->name);
 183
 184                 if (!match->ptr)
 185                 {
 186                         warn_elem(e, "refers to not existing helper '%s'", match->name);
 187                         continue;
 188                 }
 189
 190                 if (fw3_is_family(match->ptr, FW3_FAMILY_V4))
 191                         fw3_setbit(zone->flags[0], FW3_FLAG_HELPER);
 192
 193                 if (fw3_is_family(match->ptr, FW3_FAMILY_V6))
 194                         fw3_setbit(zone->flags[1], FW3_FLAG_HELPER);
 195         }
 196 }
 197
 198 struct fw3_zone *
 199 fw3_alloc_zone(void)
 200 {
 201         struct fw3_zone *zone;
 202
 203         zone = calloc(1, sizeof(*zone));
 204         if (!zone)
 205                 return NULL;
 206
 207         INIT_LIST_HEAD(&zone->networks);
 208         INIT_LIST_HEAD(&zone->devices);
 209         INIT_LIST_HEAD(&zone->subnets);
 210         INIT_LIST_HEAD(&zone->masq_src);
 211         INIT_LIST_HEAD(&zone->masq_dest);
 212         INIT_LIST_HEAD(&zone->cthelpers);
 213
 214         INIT_LIST_HEAD(&zone->old_addrs);
 215
 216         zone->enabled = true;
 217         zone->auto_helper = true;
 218         zone->custom_chains = true;
 219         zone->log_limit.rate = 10;
 220
 221         return zone;
 222 }
 223
 224 void
 225 fw3_load_zones(struct fw3_state *state, struct uci_package *p)
 226 {
 227         struct uci_section *s;
 228         struct uci_element *e;
 229         struct fw3_zone *zone;
 230         struct fw3_defaults *defs = &state->defaults;
 231
 232         INIT_LIST_HEAD(&state->zones);
 233
 234         uci_foreach_element(&p->sections, e)
 235         {
 236                 s = uci_to_section(e);
 237
 238                 if (strcmp(s->type, "zone"))
 239                         continue;
 240
 241                 zone = fw3_alloc_zone();
 242
 243                 if (!zone)
 244                         continue;
 245
 246                 if (!fw3_parse_options(zone, fw3_zone_opts, s))
 247                         warn_elem(e, "has invalid options");
 248
 249                 if (!zone->enabled)
 250                 {
 251                         fw3_free_zone(zone);
 252                         continue;
 253                 }
 254
 255                 if (!zone->extra_dest)
 256                         zone->extra_dest = zone->extra_src;
 257
 258                 if (!defs->custom_chains && zone->custom_chains)
 259                         zone->custom_chains = false;
 260
 261                 if (!defs->auto_helper && zone->auto_helper)
 262                         zone->auto_helper = false;
 263
 264                 if (!zone->name || !*zone->name)
 265                 {
 266                         warn_elem(e, "has no name - ignoring");
 267                         fw3_free_zone(zone);
 268                         continue;
 269                 }
 270
 271                 if (strlen(zone->name) > FW3_ZONE_MAXNAMELEN)
 272                 {
 273                         warn_elem(e, "must not have a name longer than %u characters",
 274                                      FW3_ZONE_MAXNAMELEN);
 275                         fw3_free_zone(zone);
 276                         continue;
 277                 }
 278
 279                 fw3_ubus_zone_devices(zone);
 280
 281                 if (list_empty(&zone->networks) && list_empty(&zone->devices) &&
 282                     list_empty(&zone->subnets) && !zone->extra_src)
 283                 {
 284                         warn_elem(e, "has no device, network, subnet or extra options");
 285                 }
 286
 287                 if (!check_masq_addrs(&zone->masq_src))
 288                 {
 289                         warn_elem(e, "has unresolved masq_src, disabling masq");
 290                         zone->masq = false;
 291                 }
 292
 293                 if (!check_masq_addrs(&zone->masq_dest))
 294                 {
 295                         warn_elem(e, "has unresolved masq_dest, disabling masq");
 296                         zone->masq = false;
 297                 }
 298
 299                 check_policy(e, &zone->policy_input, defs->policy_input, "input");
 300                 check_policy(e, &zone->policy_output, defs->policy_output, "output");
 301                 check_policy(e, &zone->policy_forward, defs->policy_forward, "forward");
 302
 303                 resolve_networks(e, zone);
 304
 305                 if (zone->masq)
 306                 {
 307                         fw3_setbit(zone->flags[0], FW3_FLAG_SNAT);
 308                 }
 309
 310                 if (zone->custom_chains)
 311                 {
 312                         fw3_setbit(zone->flags[0], FW3_FLAG_SNAT);
 313                         fw3_setbit(zone->flags[0], FW3_FLAG_DNAT);
 314                 }
 315
 316                 resolve_cthelpers(state, e, zone);
 317
 318                 fw3_setbit(zone->flags[0], fw3_to_src_target(zone->policy_input));
 319                 fw3_setbit(zone->flags[0], zone->policy_forward);
 320                 fw3_setbit(zone->flags[0], zone->policy_output);
 321
 322                 fw3_setbit(zone->flags[1], fw3_to_src_target(zone->policy_input));
 323                 fw3_setbit(zone->flags[1], zone->policy_forward);
 324                 fw3_setbit(zone->flags[1], zone->policy_output);
 325
 326                 list_add_tail(&zone->list, &state->zones);
 327         }
 328 }
 329
 330
 331 static void
 332 print_zone_chain(struct fw3_ipt_handle *handle, struct fw3_state *state,
 333                  bool reload, struct fw3_zone *zone)
 334 {
 335         int i;
 336         struct fw3_ipt_rule *r;
 337         const struct fw3_chain_spec *c;
 338
 339         const char *flt_chains[] = {
 340                 "input",   "input",
 341                 "output",  "output",
 342                 "forward", "forwarding",
 343         };
 344
 345         const char *nat_chains[] = {
 346                 "prerouting",  "prerouting",
 347                 "postrouting", "postrouting",
 348         };
 349
 350         if (!fw3_is_family(zone, handle->family))
 351                 return;
 352
 353         set(zone->flags, handle->family, handle->table);
 354
 355         if (zone->custom_chains)
 356                 set(zone->flags, handle->family, FW3_FLAG_CUSTOM_CHAINS);
 357
 358         for (c = zone_chains; c->format; c++)
 359         {
 360                 /* don't touch user chains on selective stop */
 361                 if (reload && c->flag == FW3_FLAG_CUSTOM_CHAINS)
 362                         continue;
 363
 364                 if (!fw3_is_family(c, handle->family))
 365                         continue;
 366
 367                 if (c->table != handle->table)
 368                         continue;
 369
 370                 if (c->flag &&
 371                     !fw3_hasbit(zone->flags[handle->family == FW3_FAMILY_V6], c->flag))
 372                         continue;
 373
 374                 fw3_ipt_create_chain(handle, c->format, zone->name);
 375         }
 376
 377         if (zone->custom_chains)
 378         {
 379                 if (handle->table == FW3_TABLE_FILTER)
 380                 {
 381                         for (i = 0; i < sizeof(flt_chains)/sizeof(flt_chains[0]); i += 2)
 382                         {
 383                                 r = fw3_ipt_rule_new(handle);
 384                                 fw3_ipt_rule_comment(r, "Custom %s %s rule chain", zone->name, flt_chains[i+1]);
 385                                 fw3_ipt_rule_target(r, "%s_%s_rule", flt_chains[i+1], zone->name);
 386                                 fw3_ipt_rule_append(r, "zone_%s_%s", zone->name, flt_chains[i]);
 387                         }
 388                 }
 389                 else if (handle->table == FW3_TABLE_NAT)
 390                 {
 391                         for (i = 0; i < sizeof(nat_chains)/sizeof(nat_chains[0]); i += 2)
 392                         {
 393                                 r = fw3_ipt_rule_new(handle);
 394                                 fw3_ipt_rule_comment(r, "Custom %s %s rule chain", zone->name, nat_chains[i+1]);
 395                                 fw3_ipt_rule_target(r, "%s_%s_rule", nat_chains[i+1], zone->name);
 396                                 fw3_ipt_rule_append(r, "zone_%s_%s", zone->name, nat_chains[i]);
 397                         }
 398                 }
 399         }
 400
 401         set(zone->flags, handle->family, handle->table);
 402 }
 403
 404 static void
 405 print_interface_rule(struct fw3_ipt_handle *handle, struct fw3_state *state,
 406                                          bool reload, struct fw3_zone *zone,
 407                      struct fw3_device *dev, struct fw3_address *sub)
 408 {
 409         struct fw3_protocol tcp = { .protocol = 6 };
 410         struct fw3_ipt_rule *r;
 411         enum fw3_flag t;
 412
 413         char buf[32];
 414
 415         int i;
 416
 417         const char *chains[] = {
 418                 "input", "INPUT",
 419                 "output", "OUTPUT",
 420                 "forward", "FORWARD",
 421         };
 422
 423 #define jump_target(t) \
 424         ((t == FW3_FLAG_REJECT) ? "reject" : fw3_flag_names[t])
 425
 426         if (handle->table == FW3_TABLE_FILTER)
 427         {
 428                 for (t = FW3_FLAG_ACCEPT; t <= FW3_FLAG_DROP; t++)
 429                 {
 430                         if (t > FW3_FLAG_ACCEPT && zone->log & FW3_ZONE_LOG_FILTER)
 431                         {
 432                                 if (has(zone->flags, handle->family, fw3_to_src_target(t)))
 433                                 {
 434                                         r = fw3_ipt_rule_create(handle, NULL, dev, NULL, sub, NULL);
 435
 436                                         snprintf(buf, sizeof(buf) - 1, "%s %s in: ",
 437                                                  fw3_flag_names[t], zone->name);
 438
 439                                         fw3_ipt_rule_limit(r, &zone->log_limit);
 440                                         fw3_ipt_rule_target(r, "LOG");
 441                                         fw3_ipt_rule_addarg(r, false, "--log-prefix", buf);
 442                                         fw3_ipt_rule_replace(r, "zone_%s_src_%s",
 443                                                              zone->name, fw3_flag_names[t]);
 444                                 }
 445
 446                                 if (has(zone->flags, handle->family, t))
 447                                 {
 448                                         r = fw3_ipt_rule_create(handle, NULL, NULL, dev, NULL, sub);
 449
 450                                         snprintf(buf, sizeof(buf) - 1, "%s %s out: ",
 451                                                  fw3_flag_names[t], zone->name);
 452
 453                                         fw3_ipt_rule_limit(r, &zone->log_limit);
 454                                         fw3_ipt_rule_target(r, "LOG");
 455                                         fw3_ipt_rule_addarg(r, false, "--log-prefix", buf);
 456                                         fw3_ipt_rule_replace(r, "zone_%s_dest_%s",
 457                                                              zone->name, fw3_flag_names[t]);
 458                                 }
 459                         }
 460
 461                         if (has(zone->flags, handle->family, fw3_to_src_target(t)))
 462                         {
 463                                 r = fw3_ipt_rule_create(handle, NULL, dev, NULL, sub, NULL);
 464                                 fw3_ipt_rule_target(r, jump_target(t));
 465                                 fw3_ipt_rule_extra(r, zone->extra_src);
 466
 467                                 if (t == FW3_FLAG_ACCEPT && !state->defaults.drop_invalid)
 468                                         fw3_ipt_rule_extra(r,
 469                                                            "-m conntrack --ctstate NEW,UNTRACKED");
 470
 471                                 fw3_ipt_rule_replace(r, "zone_%s_src_%s", zone->name,
 472                                                      fw3_flag_names[t]);
 473                         }
 474
 475                         if (has(zone->flags, handle->family, t))
 476                         {
 477                                 if (t == FW3_FLAG_ACCEPT &&
 478                                     zone->masq && !zone->masq_allow_invalid)
 479                                 {
 480                                         r = fw3_ipt_rule_create(handle, NULL, NULL, dev, NULL, sub);
 481                                         fw3_ipt_rule_extra(r, "-m conntrack --ctstate INVALID");
 482                                         fw3_ipt_rule_comment(r, "Prevent NAT leakage");
 483                                         fw3_ipt_rule_target(r, fw3_flag_names[FW3_FLAG_DROP]);
 484                                         fw3_ipt_rule_replace(r, "zone_%s_dest_%s", zone->name,
 485                                                              fw3_flag_names[t]);
 486                                 }
 487
 488                                 r = fw3_ipt_rule_create(handle, NULL, NULL, dev, NULL, sub);
 489                                 fw3_ipt_rule_target(r, jump_target(t));
 490                                 fw3_ipt_rule_extra(r, zone->extra_dest);
 491                                 fw3_ipt_rule_replace(r, "zone_%s_dest_%s", zone->name,
 492                                                      fw3_flag_names[t]);
 493                         }
 494                 }
 495
 496                 for (i = 0; i < sizeof(chains)/sizeof(chains[0]); i += 2)
 497                 {
 498                         if (*chains[i] == 'o')
 499                                 r = fw3_ipt_rule_create(handle, NULL, NULL, dev, NULL, sub);
 500                         else
 501                                 r = fw3_ipt_rule_create(handle, NULL, dev, NULL, sub, NULL);
 502
 503                         fw3_ipt_rule_target(r, "zone_%s_%s", zone->name, chains[i]);
 504
 505                         if (*chains[i] == 'o')
 506                                 fw3_ipt_rule_extra(r, zone->extra_dest);
 507                         else
 508                                 fw3_ipt_rule_extra(r, zone->extra_src);
 509
 510                         fw3_ipt_rule_replace(r, chains[i + 1]);
 511                 }
 512         }
 513         else if (handle->table == FW3_TABLE_NAT)
 514         {
 515                 if (has(zone->flags, handle->family, FW3_FLAG_DNAT))
 516                 {
 517                         r = fw3_ipt_rule_create(handle, NULL, dev, NULL, sub, NULL);
 518                         fw3_ipt_rule_target(r, "zone_%s_prerouting", zone->name);
 519                         fw3_ipt_rule_extra(r, zone->extra_src);
 520                         fw3_ipt_rule_replace(r, "PREROUTING");
 521                 }
 522
 523                 if (has(zone->flags, handle->family, FW3_FLAG_SNAT))
 524                 {
 525                         r = fw3_ipt_rule_create(handle, NULL, NULL, dev, NULL, sub);
 526                         fw3_ipt_rule_target(r, "zone_%s_postrouting", zone->name);
 527                         fw3_ipt_rule_extra(r, zone->extra_dest);
 528                         fw3_ipt_rule_replace(r, "POSTROUTING");
 529                 }
 530         }
 531         else if (handle->table == FW3_TABLE_MANGLE)
 532         {
 533                 if (zone->mtu_fix)
 534                 {
 535                         if (zone->log & FW3_ZONE_LOG_MANGLE)
 536                         {
 537                                 snprintf(buf, sizeof(buf) - 1, "MSSFIX %s out: ", zone->name);
 538
 539                                 r = fw3_ipt_rule_create(handle, &tcp, NULL, dev, NULL, sub);
 540                                 fw3_ipt_rule_addarg(r, false, "--tcp-flags", "SYN,RST");
 541                                 fw3_ipt_rule_addarg(r, false, "SYN", NULL);
 542                                 fw3_ipt_rule_limit(r, &zone->log_limit);
 543                                 fw3_ipt_rule_comment(r, "Zone %s MTU fix logging", zone->name);
 544                                 fw3_ipt_rule_target(r, "LOG");
 545                                 fw3_ipt_rule_addarg(r, false, "--log-prefix", buf);
 546                                 fw3_ipt_rule_replace(r, "FORWARD");
 547                         }
 548
 549                         r = fw3_ipt_rule_create(handle, &tcp, NULL, dev, NULL, sub);
 550                         fw3_ipt_rule_addarg(r, false, "--tcp-flags", "SYN,RST");
 551                         fw3_ipt_rule_addarg(r, false, "SYN", NULL);
 552                         fw3_ipt_rule_comment(r, "Zone %s MTU fixing", zone->name);
 553                         fw3_ipt_rule_target(r, "TCPMSS");
 554                         fw3_ipt_rule_addarg(r, false, "--clamp-mss-to-pmtu", NULL);
 555                         fw3_ipt_rule_replace(r, "FORWARD");
 556                 }
 557         }
 558         else if (handle->table == FW3_TABLE_RAW)
 559         {
 560                 if (has(zone->flags, handle->family, FW3_FLAG_HELPER))
 561                 {
 562                         r = fw3_ipt_rule_create(handle, NULL, dev, NULL, sub, NULL);
 563                         fw3_ipt_rule_comment(r, "%s CT helper assignment", zone->name);
 564                         fw3_ipt_rule_target(r, "zone_%s_helper", zone->name);
 565                         fw3_ipt_rule_extra(r, zone->extra_src);
 566                         fw3_ipt_rule_replace(r, "PREROUTING");
 567                 }
 568
 569                 if (has(zone->flags, handle->family, FW3_FLAG_NOTRACK))
 570                 {
 571                         r = fw3_ipt_rule_create(handle, NULL, dev, NULL, sub, NULL);
 572                         fw3_ipt_rule_comment(r, "%s CT bypass", zone->name);
 573                         fw3_ipt_rule_target(r, "zone_%s_notrack", zone->name);
 574                         fw3_ipt_rule_extra(r, zone->extra_src);
 575                         fw3_ipt_rule_replace(r, "PREROUTING");
 576                 }
 577         }
 578 }
 579
 580 static void
 581 print_interface_rules(struct fw3_ipt_handle *handle, struct fw3_state *state,
 582                       bool reload, struct fw3_zone *zone)
 583 {
 584         struct fw3_device *dev;
 585         struct fw3_address *sub;
 586
 587         fw3_foreach(dev, &zone->devices)
 588         fw3_foreach(sub, &zone->subnets)
 589         {
 590                 if (!fw3_is_family(sub, handle->family))
 591                         continue;
 592
 593                 if (!dev && !sub)
 594                         continue;
 595
 596                 print_interface_rule(handle, state, reload, zone, dev, sub);
 597         }
 598 }
 599
 600 static struct fw3_address *
 601 next_addr(struct fw3_address *addr, struct list_head *list,
 602                 enum fw3_family family, bool invert)
 603 {
 604         struct list_head *p;
 605         struct fw3_address *rv;
 606
 607         for (p = addr ? addr->list.next : list->next; p != list; p = p->next)
 608         {
 609                 rv = list_entry(p, struct fw3_address, list);
 610
 611                 if (fw3_is_family(rv, family) && rv->set && rv->invert == invert)
 612                         return rv;
 613         }
 614
 615         return NULL;
 616 }
 617
 618 static void
 619 print_zone_rule(struct fw3_ipt_handle *handle, struct fw3_state *state,
 620                 bool reload, struct fw3_zone *zone)
 621 {
 622         bool first_src, first_dest;
 623         struct fw3_address *msrc;
 624         struct fw3_address *mdest;
 625         struct fw3_ipt_rule *r;
 626
 627         if (!fw3_is_family(zone, handle->family))
 628                 return;
 629
 630         info("   * Zone '%s'", zone->name);
 631
 632         switch (handle->table)
 633         {
 634         case FW3_TABLE_FILTER:
 635                 if (has(zone->flags, handle->family, FW3_FLAG_DNAT))
 636                 {
 637                         r = fw3_ipt_rule_new(handle);
 638                         fw3_ipt_rule_extra(r, "-m conntrack --ctstate DNAT");
 639                         fw3_ipt_rule_comment(r, "Accept port redirections");
 640                         fw3_ipt_rule_target(r, fw3_flag_names[FW3_FLAG_ACCEPT]);
 641                         fw3_ipt_rule_append(r, "zone_%s_input", zone->name);
 642
 643                         r = fw3_ipt_rule_new(handle);
 644                         fw3_ipt_rule_extra(r, "-m conntrack --ctstate DNAT");
 645                         fw3_ipt_rule_comment(r, "Accept port forwards");
 646                         fw3_ipt_rule_target(r, fw3_flag_names[FW3_FLAG_ACCEPT]);
 647                         fw3_ipt_rule_append(r, "zone_%s_forward", zone->name);
 648                 }
 649
 650                 r = fw3_ipt_rule_new(handle);
 651                 fw3_ipt_rule_target(r, "zone_%s_src_%s", zone->name,
 652                                      fw3_flag_names[zone->policy_input]);
 653                 fw3_ipt_rule_append(r, "zone_%s_input", zone->name);
 654
 655                 r = fw3_ipt_rule_new(handle);
 656                 fw3_ipt_rule_target(r, "zone_%s_dest_%s", zone->name,
 657                                      fw3_flag_names[zone->policy_forward]);
 658                 fw3_ipt_rule_append(r, "zone_%s_forward", zone->name);
 659
 660                 r = fw3_ipt_rule_new(handle);
 661                 fw3_ipt_rule_target(r, "zone_%s_dest_%s", zone->name,
 662                                      fw3_flag_names[zone->policy_output]);
 663                 fw3_ipt_rule_append(r, "zone_%s_output", zone->name);
 664
 665                 break;
 666
 667         case FW3_TABLE_NAT:
 668                 if (zone->masq && handle->family == FW3_FAMILY_V4)
 669                 {
 670                         /* for any negated masq_src ip, emit -s addr -j RETURN rules */
 671                         for (msrc = NULL;
 672                              (msrc = next_addr(msrc, &zone->masq_src,
 673                                                handle->family, true)) != NULL; )
 674                         {
 675                                 msrc->invert = false;
 676                                 r = fw3_ipt_rule_new(handle);
 677                                 fw3_ipt_rule_src_dest(r, msrc, NULL);
 678                                 fw3_ipt_rule_target(r, "RETURN");
 679                                 fw3_ipt_rule_append(r, "zone_%s_postrouting", zone->name);
 680                                 msrc->invert = true;
 681                         }
 682
 683                         /* for any negated masq_dest ip, emit -d addr -j RETURN rules */
 684                         for (mdest = NULL;
 685                              (mdest = next_addr(mdest, &zone->masq_dest,
 686                                                 handle->family, true)) != NULL; )
 687                         {
 688                                 mdest->invert = false;
 689                                 r = fw3_ipt_rule_new(handle);
 690                                 fw3_ipt_rule_src_dest(r, NULL, mdest);
 691                                 fw3_ipt_rule_target(r, "RETURN");
 692                                 fw3_ipt_rule_append(r, "zone_%s_postrouting", zone->name);
 693                                 mdest->invert = true;
 694                         }
 695
 696                         /* emit masquerading entries for non-negated addresses
 697                            and ensure that both src and dest loops run at least once,
 698                            even if there are no relevant addresses */
 699                         for (first_src = true, msrc = NULL;
 700                              (msrc = next_addr(msrc, &zone->masq_src,
 701                                                    handle->family, false)) || first_src;
 702                              first_src = false)
 703                         {
 704                                 for (first_dest = true, mdest = NULL;
 705                                      (mdest = next_addr(mdest, &zone->masq_dest,
 706                                                             handle->family, false)) || first_dest;
 707                                      first_dest = false)
 708                                 {
 709                                         r = fw3_ipt_rule_new(handle);
 710                                         fw3_ipt_rule_src_dest(r, msrc, mdest);
 711                                         fw3_ipt_rule_target(r, "MASQUERADE");
 712                                         fw3_ipt_rule_append(r, "zone_%s_postrouting", zone->name);
 713                                 }
 714                         }
 715                 }
 716                 break;
 717
 718         case FW3_TABLE_RAW:
 719                 fw3_print_cthelpers(handle, state, zone);
 720                 break;
 721
 722         case FW3_TABLE_MANGLE:
 723                 break;
 724         }
 725
 726         print_interface_rules(handle, state, reload, zone);
 727 }
 728
 729 void
 730 fw3_print_zone_chains(struct fw3_ipt_handle *handle, struct fw3_state *state,
 731                       bool reload)
 732 {
 733         struct fw3_zone *zone;
 734
 735         list_for_each_entry(zone, &state->zones, list)
 736                 print_zone_chain(handle, state, reload, zone);
 737 }
 738
 739 void
 740 fw3_print_zone_rules(struct fw3_ipt_handle *handle, struct fw3_state *state,
 741                      bool reload)
 742 {
 743         struct fw3_zone *zone;
 744
 745         list_for_each_entry(zone, &state->zones, list)
 746                 print_zone_rule(handle, state, reload, zone);
 747 }
 748
 749 void
 750 fw3_flush_zones(struct fw3_ipt_handle *handle, struct fw3_state *state,
 751                 bool reload)
 752 {
 753         struct fw3_zone *z, *tmp;
 754         const struct fw3_chain_spec *c;
 755         char chain[32];
 756
 757         list_for_each_entry_safe(z, tmp, &state->zones, list)
 758         {
 759                 if (!has(z->flags, handle->family, handle->table))
 760                         continue;
 761
 762                 for (c = zone_chains; c->format; c++)
 763                 {
 764                         /* don't touch user chains on selective stop */
 765                         if (reload && c->flag == FW3_FLAG_CUSTOM_CHAINS)
 766                                 continue;
 767
 768                         if (!fw3_is_family(c, handle->family))
 769                                 continue;
 770
 771                         if (c->table != handle->table)
 772                                 continue;
 773
 774                         if (c->flag && !has(z->flags, handle->family, c->flag))
 775                                 continue;
 776
 777                         snprintf(chain, sizeof(chain), c->format, z->name);
 778                         fw3_ipt_flush_chain(handle, chain);
 779
 780                         /* keep certain basic chains that do not depend on any settings to
 781                            avoid purging unrelated user rules pointing to them */
 782                         if (reload && !c->flag)
 783                                 continue;
 784
 785                         fw3_ipt_delete_chain(handle, chain);
 786                 }
 787
 788                 del(z->flags, handle->family, handle->table);
 789         }
 790 }
 791
 792 void
 793 fw3_hotplug_zones(struct fw3_state *state, bool add)
 794 {
 795         struct fw3_zone *z;
 796         struct fw3_device *d;
 797
 798         list_for_each_entry(z, &state->zones, list)
 799         {
 800                 if (add != fw3_hasbit(z->flags[0], FW3_FLAG_HOTPLUG))
 801                 {
 802                         list_for_each_entry(d, &z->devices, list)
 803                                 fw3_hotplug(add, z, d);
 804
 805                         if (add)
 806                                 fw3_setbit(z->flags[0], FW3_FLAG_HOTPLUG);
 807                         else
 808                                 fw3_delbit(z->flags[0], FW3_FLAG_HOTPLUG);
 809                 }
 810         }
 811 }
 812
 813 struct fw3_zone *
 814 fw3_lookup_zone(struct fw3_state *state, const char *name)
 815 {
 816         struct fw3_zone *z;
 817
 818         if (list_empty(&state->zones))
 819                 return NULL;
 820
 821         list_for_each_entry(z, &state->zones, list)
 822         {
 823                 if (strcmp(z->name, name))
 824                         continue;
 825
 826                 return z;
 827         }
 828
 829         return NULL;
 830 }
 831
 832 struct list_head *
 833 fw3_resolve_zone_addresses(struct fw3_zone *zone, struct fw3_address *addr)
 834 {
 835         struct fw3_device *net;
 836         struct fw3_address *cur, *tmp;
 837         struct list_head *all;
 838
 839         all = calloc(1, sizeof(*all));
 840         if (!all)
 841                 return NULL;
 842
 843         INIT_LIST_HEAD(all);
 844
 845         if (addr && addr->set)
 846         {
 847                 tmp = malloc(sizeof(*tmp));
 848
 849                 if (tmp)
 850                 {
 851                         *tmp = *addr;
 852                         list_add_tail(&tmp->list, all);
 853                 }
 854         }
 855         else
 856         {
 857                 list_for_each_entry(net, &zone->networks, list)
 858                         fw3_ubus_address(all, net->name);
 859
 860                 list_for_each_entry(cur, &zone->subnets, list)
 861                 {
 862                         tmp = malloc(sizeof(*tmp));
 863
 864                         if (!tmp)
 865                                 continue;
 866
 867                         *tmp = *cur;
 868                         list_add_tail(&tmp->list, all);
 869                 }
 870         }
 871
 872         return all;
 873 }