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 static void
 102 check_policy(struct uci_element *e, enum fw3_flag *pol, enum fw3_flag def,
 103              const char *name)
 104 {
 105         if (*pol == FW3_FLAG_UNSPEC)
 106         {
 107                 warn_elem(e, "has no %s policy specified, using default", name);
 108                 *pol = def;
 109         }
 110         else if (*pol > FW3_FLAG_DROP)
 111         {
 112                 warn_elem(e, "has invalid %s policy, using default", name);
 113                 *pol = def;
 114         }
 115 }
 116
 117 static bool
 118 check_masq_addrs(struct list_head *head)
 119 {
 120         struct fw3_address *addr;
 121         int n_addr = 0, n_failed = 0;
 122
 123         list_for_each_entry(addr, head, list)
 124         {
 125                 if (addr->invert)
 126                         continue;
 127
 128                 n_addr++;
 129
 130                 if (!addr->set && addr->resolved)
 131                         n_failed++;
 132         }
 133
 134         return (n_addr == 0 || n_failed < n_addr);
 135 }
 136
 137 static void
 138 resolve_networks(struct uci_element *e, struct fw3_zone *zone)
 139 {
 140         struct fw3_device *net, *tmp;
 141
 142         list_for_each_entry(net, &zone->networks, list)
 143         {
 144                 tmp = fw3_ubus_device(net->name);
 145
 146                 if (!tmp)
 147                 {
 148                         warn_elem(e, "cannot resolve device of network '%s'", net->name);
 149                         continue;
 150                 }
 151
 152                 snprintf(tmp->network, sizeof(tmp->network), "%s", net->name);
 153                 list_add_tail(&tmp->list, &zone->devices);
 154         }
 155 }
 156
 157 static void
 158 resolve_cthelpers(struct fw3_state *s, struct uci_element *e, struct fw3_zone *zone)
 159 {
 160         struct fw3_cthelpermatch *match;
 161
 162         if (list_empty(&zone->cthelpers))
 163         {
 164                 if (!zone->masq && zone->auto_helper)
 165                 {
 166                         fw3_setbit(zone->flags[0], FW3_FLAG_HELPER);
 167                         fw3_setbit(zone->flags[1], FW3_FLAG_HELPER);
 168                 }
 169
 170                 return;
 171         }
 172
 173         list_for_each_entry(match, &zone->cthelpers, list)
 174         {
 175                 if (match->invert)
 176                 {
 177                         warn_elem(e, "must not use a negated helper match");
 178                         continue;
 179                 }
 180
 181                 match->ptr = fw3_lookup_cthelper(s, match->name);
 182
 183                 if (!match->ptr)
 184                 {
 185                         warn_elem(e, "refers to not existing helper '%s'", match->name);
 186                         continue;
 187                 }
 188
 189                 if (fw3_is_family(match->ptr, FW3_FAMILY_V4))
 190                         fw3_setbit(zone->flags[0], FW3_FLAG_HELPER);
 191
 192                 if (fw3_is_family(match->ptr, FW3_FAMILY_V6))
 193                         fw3_setbit(zone->flags[1], FW3_FLAG_HELPER);
 194         }
 195 }
 196
 197 struct fw3_zone *
 198 fw3_alloc_zone(void)
 199 {
 200         struct fw3_zone *zone;
 201
 202         zone = calloc(1, sizeof(*zone));
 203         if (!zone)
 204                 return NULL;
 205
 206         INIT_LIST_HEAD(&zone->networks);
 207         INIT_LIST_HEAD(&zone->devices);
 208         INIT_LIST_HEAD(&zone->subnets);
 209         INIT_LIST_HEAD(&zone->masq_src);
 210         INIT_LIST_HEAD(&zone->masq_dest);
 211         INIT_LIST_HEAD(&zone->cthelpers);
 212
 213         INIT_LIST_HEAD(&zone->old_addrs);
 214
 215         zone->enabled = true;
 216         zone->auto_helper = true;
 217         zone->custom_chains = true;
 218         zone->log_limit.rate = 10;
 219
 220         return zone;
 221 }
 222
 223 void
 224 fw3_load_zones(struct fw3_state *state, struct uci_package *p)
 225 {
 226         struct uci_section *s;
 227         struct uci_element *e;
 228         struct fw3_zone *zone;
 229         struct fw3_defaults *defs = &state->defaults;
 230
 231         INIT_LIST_HEAD(&state->zones);
 232
 233         uci_foreach_element(&p->sections, e)
 234         {
 235                 s = uci_to_section(e);
 236
 237                 if (strcmp(s->type, "zone"))
 238                         continue;
 239
 240                 zone = fw3_alloc_zone();
 241
 242                 if (!zone)
 243                         continue;
 244
 245                 if (!fw3_parse_options(zone, fw3_zone_opts, s))
 246                         warn_elem(e, "has invalid options");
 247
 248                 if (!zone->enabled)
 249                 {
 250                         fw3_free_zone(zone);
 251                         continue;
 252                 }
 253
 254                 if (!zone->extra_dest)
 255                         zone->extra_dest = zone->extra_src;
 256
 257                 if (!defs->custom_chains && zone->custom_chains)
 258                         zone->custom_chains = false;
 259
 260                 if (!defs->auto_helper && zone->auto_helper)
 261                         zone->auto_helper = false;
 262
 263                 if (!zone->name || !*zone->name)
 264                 {
 265                         warn_elem(e, "has no name - ignoring");
 266                         fw3_free_zone(zone);
 267                         continue;
 268                 }
 269
 270                 if (strlen(zone->name) > FW3_ZONE_MAXNAMELEN)
 271                 {
 272                         warn_elem(e, "must not have a name longer than %u characters",
 273                                      FW3_ZONE_MAXNAMELEN);
 274                         fw3_free_zone(zone);
 275                         continue;
 276                 }
 277
 278                 fw3_ubus_zone_devices(zone);
 279
 280                 if (list_empty(&zone->networks) && list_empty(&zone->devices) &&
 281                     list_empty(&zone->subnets) && !zone->extra_src)
 282                 {
 283                         warn_elem(e, "has no device, network, subnet or extra options");
 284                 }
 285
 286                 if (!check_masq_addrs(&zone->masq_src))
 287                 {
 288                         warn_elem(e, "has unresolved masq_src, disabling masq");
 289                         zone->masq = false;
 290                 }
 291
 292                 if (!check_masq_addrs(&zone->masq_dest))
 293                 {
 294                         warn_elem(e, "has unresolved masq_dest, disabling masq");
 295                         zone->masq = false;
 296                 }
 297
 298                 check_policy(e, &zone->policy_input, defs->policy_input, "input");
 299                 check_policy(e, &zone->policy_output, defs->policy_output, "output");
 300                 check_policy(e, &zone->policy_forward, defs->policy_forward, "forward");
 301
 302                 resolve_networks(e, zone);
 303
 304                 if (zone->masq)
 305                 {
 306                         fw3_setbit(zone->flags[0], FW3_FLAG_SNAT);
 307                 }
 308
 309                 if (zone->custom_chains)
 310                 {
 311                         fw3_setbit(zone->flags[0], FW3_FLAG_SNAT);
 312                         fw3_setbit(zone->flags[0], FW3_FLAG_DNAT);
 313                 }
 314
 315                 resolve_cthelpers(state, e, zone);
 316
 317                 fw3_setbit(zone->flags[0], fw3_to_src_target(zone->policy_input));
 318                 fw3_setbit(zone->flags[0], zone->policy_forward);
 319                 fw3_setbit(zone->flags[0], zone->policy_output);
 320
 321                 fw3_setbit(zone->flags[1], fw3_to_src_target(zone->policy_input));
 322                 fw3_setbit(zone->flags[1], zone->policy_forward);
 323                 fw3_setbit(zone->flags[1], zone->policy_output);
 324
 325                 list_add_tail(&zone->list, &state->zones);
 326         }
 327 }
 328
 329
 330 static void
 331 print_zone_chain(struct fw3_ipt_handle *handle, struct fw3_state *state,
 332                  bool reload, struct fw3_zone *zone)
 333 {
 334         int i;
 335         struct fw3_ipt_rule *r;
 336         const struct fw3_chain_spec *c;
 337
 338         const char *flt_chains[] = {
 339                 "input",   "input",
 340                 "output",  "output",
 341                 "forward", "forwarding",
 342         };
 343
 344         const char *nat_chains[] = {
 345                 "prerouting",  "prerouting",
 346                 "postrouting", "postrouting",
 347         };
 348
 349         if (!fw3_is_family(zone, handle->family))
 350                 return;
 351
 352         set(zone->flags, handle->family, handle->table);
 353
 354         if (zone->custom_chains)
 355                 set(zone->flags, handle->family, FW3_FLAG_CUSTOM_CHAINS);
 356
 357         for (c = zone_chains; c->format; c++)
 358         {
 359                 /* don't touch user chains on selective stop */
 360                 if (reload && c->flag == FW3_FLAG_CUSTOM_CHAINS)
 361                         continue;
 362
 363                 if (!fw3_is_family(c, handle->family))
 364                         continue;
 365
 366                 if (c->table != handle->table)
 367                         continue;
 368
 369                 if (c->flag &&
 370                     !fw3_hasbit(zone->flags[handle->family == FW3_FAMILY_V6], c->flag))
 371                         continue;
 372
 373                 fw3_ipt_create_chain(handle, c->format, zone->name);
 374         }
 375
 376         if (zone->custom_chains)
 377         {
 378                 if (handle->table == FW3_TABLE_FILTER)
 379                 {
 380                         for (i = 0; i < sizeof(flt_chains)/sizeof(flt_chains[0]); i += 2)
 381                         {
 382                                 r = fw3_ipt_rule_new(handle);
 383                                 fw3_ipt_rule_comment(r, "Custom %s %s rule chain", zone->name, flt_chains[i+1]);
 384                                 fw3_ipt_rule_target(r, "%s_%s_rule", flt_chains[i+1], zone->name);
 385                                 fw3_ipt_rule_append(r, "zone_%s_%s", zone->name, flt_chains[i]);
 386                         }
 387                 }
 388                 else if (handle->table == FW3_TABLE_NAT)
 389                 {
 390                         for (i = 0; i < sizeof(nat_chains)/sizeof(nat_chains[0]); i += 2)
 391                         {
 392                                 r = fw3_ipt_rule_new(handle);
 393                                 fw3_ipt_rule_comment(r, "Custom %s %s rule chain", zone->name, nat_chains[i+1]);
 394                                 fw3_ipt_rule_target(r, "%s_%s_rule", nat_chains[i+1], zone->name);
 395                                 fw3_ipt_rule_append(r, "zone_%s_%s", zone->name, nat_chains[i]);
 396                         }
 397                 }
 398         }
 399
 400         set(zone->flags, handle->family, handle->table);
 401 }
 402
 403 static void
 404 print_interface_rule(struct fw3_ipt_handle *handle, struct fw3_state *state,
 405                                          bool reload, struct fw3_zone *zone,
 406                      struct fw3_device *dev, struct fw3_address *sub)
 407 {
 408         struct fw3_protocol tcp = { .protocol = 6 };
 409         struct fw3_ipt_rule *r;
 410         enum fw3_flag t;
 411
 412         char buf[32];
 413
 414         int i;
 415
 416         const char *chains[] = {
 417                 "input", "INPUT",
 418                 "output", "OUTPUT",
 419                 "forward", "FORWARD",
 420         };
 421
 422 #define jump_target(t) \
 423         ((t == FW3_FLAG_REJECT) ? "reject" : fw3_flag_names[t])
 424
 425         if (handle->table == FW3_TABLE_FILTER)
 426         {
 427                 for (t = FW3_FLAG_ACCEPT; t <= FW3_FLAG_DROP; t++)
 428                 {
 429                         if (t > FW3_FLAG_ACCEPT && zone->log & FW3_ZONE_LOG_FILTER)
 430                         {
 431                                 if (has(zone->flags, handle->family, fw3_to_src_target(t)))
 432                                 {
 433                                         r = fw3_ipt_rule_create(handle, NULL, dev, NULL, sub, NULL);
 434
 435                                         snprintf(buf, sizeof(buf) - 1, "%s %s in: ",
 436                                                  fw3_flag_names[t], zone->name);
 437
 438                                         fw3_ipt_rule_limit(r, &zone->log_limit);
 439                                         fw3_ipt_rule_target(r, "LOG");
 440                                         fw3_ipt_rule_addarg(r, false, "--log-prefix", buf);
 441                                         fw3_ipt_rule_replace(r, "zone_%s_src_%s",
 442                                                              zone->name, fw3_flag_names[t]);
 443                                 }
 444
 445                                 if (has(zone->flags, handle->family, t))
 446                                 {
 447                                         r = fw3_ipt_rule_create(handle, NULL, NULL, dev, NULL, sub);
 448
 449                                         snprintf(buf, sizeof(buf) - 1, "%s %s out: ",
 450                                                  fw3_flag_names[t], zone->name);
 451
 452                                         fw3_ipt_rule_limit(r, &zone->log_limit);
 453                                         fw3_ipt_rule_target(r, "LOG");
 454                                         fw3_ipt_rule_addarg(r, false, "--log-prefix", buf);
 455                                         fw3_ipt_rule_replace(r, "zone_%s_dest_%s",
 456                                                              zone->name, fw3_flag_names[t]);
 457                                 }
 458                         }
 459
 460                         if (has(zone->flags, handle->family, fw3_to_src_target(t)))
 461                         {
 462                                 r = fw3_ipt_rule_create(handle, NULL, dev, NULL, sub, NULL);
 463                                 fw3_ipt_rule_target(r, jump_target(t));
 464                                 fw3_ipt_rule_extra(r, zone->extra_src);
 465
 466                                 if (t == FW3_FLAG_ACCEPT && !state->defaults.drop_invalid)
 467                                         fw3_ipt_rule_extra(r,
 468                                                            "-m conntrack --ctstate NEW,UNTRACKED");
 469
 470                                 fw3_ipt_rule_replace(r, "zone_%s_src_%s", zone->name,
 471                                                      fw3_flag_names[t]);
 472                         }
 473
 474                         if (has(zone->flags, handle->family, t))
 475                         {
 476                                 if (t == FW3_FLAG_ACCEPT &&
 477                                     zone->masq && !zone->masq_allow_invalid)
 478                                 {
 479                                         r = fw3_ipt_rule_create(handle, NULL, NULL, dev, NULL, sub);
 480                                         fw3_ipt_rule_extra(r, "-m conntrack --ctstate INVALID");
 481                                         fw3_ipt_rule_comment(r, "Prevent NAT leakage");
 482                                         fw3_ipt_rule_target(r, fw3_flag_names[FW3_FLAG_DROP]);
 483                                         fw3_ipt_rule_replace(r, "zone_%s_dest_%s", zone->name,
 484                                                              fw3_flag_names[t]);
 485                                 }
 486
 487                                 r = fw3_ipt_rule_create(handle, NULL, NULL, dev, NULL, sub);
 488                                 fw3_ipt_rule_target(r, jump_target(t));
 489                                 fw3_ipt_rule_extra(r, zone->extra_dest);
 490                                 fw3_ipt_rule_replace(r, "zone_%s_dest_%s", zone->name,
 491                                                      fw3_flag_names[t]);
 492                         }
 493                 }
 494
 495                 for (i = 0; i < sizeof(chains)/sizeof(chains[0]); i += 2)
 496                 {
 497                         if (*chains[i] == 'o')
 498                                 r = fw3_ipt_rule_create(handle, NULL, NULL, dev, NULL, sub);
 499                         else
 500                                 r = fw3_ipt_rule_create(handle, NULL, dev, NULL, sub, NULL);
 501
 502                         fw3_ipt_rule_target(r, "zone_%s_%s", zone->name, chains[i]);
 503
 504                         if (*chains[i] == 'o')
 505                                 fw3_ipt_rule_extra(r, zone->extra_dest);
 506                         else
 507                                 fw3_ipt_rule_extra(r, zone->extra_src);
 508
 509                         fw3_ipt_rule_replace(r, chains[i + 1]);
 510                 }
 511         }
 512         else if (handle->table == FW3_TABLE_NAT)
 513         {
 514                 if (has(zone->flags, handle->family, FW3_FLAG_DNAT))
 515                 {
 516                         r = fw3_ipt_rule_create(handle, NULL, dev, NULL, sub, NULL);
 517                         fw3_ipt_rule_target(r, "zone_%s_prerouting", zone->name);
 518                         fw3_ipt_rule_extra(r, zone->extra_src);
 519                         fw3_ipt_rule_replace(r, "PREROUTING");
 520                 }
 521
 522                 if (has(zone->flags, handle->family, FW3_FLAG_SNAT))
 523                 {
 524                         r = fw3_ipt_rule_create(handle, NULL, NULL, dev, NULL, sub);
 525                         fw3_ipt_rule_target(r, "zone_%s_postrouting", zone->name);
 526                         fw3_ipt_rule_extra(r, zone->extra_dest);
 527                         fw3_ipt_rule_replace(r, "POSTROUTING");
 528                 }
 529         }
 530         else if (handle->table == FW3_TABLE_MANGLE)
 531         {
 532                 if (zone->mtu_fix)
 533                 {
 534                         if (zone->log & FW3_ZONE_LOG_MANGLE)
 535                         {
 536                                 snprintf(buf, sizeof(buf) - 1, "MSSFIX %s out: ", zone->name);
 537
 538                                 r = fw3_ipt_rule_create(handle, &tcp, NULL, dev, NULL, sub);
 539                                 fw3_ipt_rule_addarg(r, false, "--tcp-flags", "SYN,RST");
 540                                 fw3_ipt_rule_addarg(r, false, "SYN", NULL);
 541                                 fw3_ipt_rule_limit(r, &zone->log_limit);
 542                                 fw3_ipt_rule_comment(r, "Zone %s MTU fix logging", zone->name);
 543                                 fw3_ipt_rule_target(r, "LOG");
 544                                 fw3_ipt_rule_addarg(r, false, "--log-prefix", buf);
 545                                 fw3_ipt_rule_replace(r, "FORWARD");
 546                         }
 547
 548                         r = fw3_ipt_rule_create(handle, &tcp, NULL, dev, NULL, sub);
 549                         fw3_ipt_rule_addarg(r, false, "--tcp-flags", "SYN,RST");
 550                         fw3_ipt_rule_addarg(r, false, "SYN", NULL);
 551                         fw3_ipt_rule_comment(r, "Zone %s MTU fixing", zone->name);
 552                         fw3_ipt_rule_target(r, "TCPMSS");
 553                         fw3_ipt_rule_addarg(r, false, "--clamp-mss-to-pmtu", NULL);
 554                         fw3_ipt_rule_replace(r, "FORWARD");
 555                 }
 556         }
 557         else if (handle->table == FW3_TABLE_RAW)
 558         {
 559                 bool loopback_dev = (dev != NULL && !dev->any &&
 560                                      !dev->invert && fw3_check_loopback_dev(dev->name));
 561                 char *chain = loopback_dev || (sub != NULL && !sub->invert && fw3_check_loopback_addr(sub)) ?
 562                               "OUTPUT" : "PREROUTING";
 563
 564                 if (has(zone->flags, handle->family, FW3_FLAG_HELPER))
 565                 {
 566                         r = fw3_ipt_rule_create(handle, NULL, loopback_dev ? NULL : dev, NULL, sub, NULL);
 567                         fw3_ipt_rule_comment(r, "%s CT helper assignment", zone->name);
 568                         fw3_ipt_rule_target(r, "zone_%s_helper", zone->name);
 569                         fw3_ipt_rule_extra(r, zone->extra_src);
 570                         fw3_ipt_rule_replace(r, chain);
 571                 }
 572
 573                 if (has(zone->flags, handle->family, FW3_FLAG_NOTRACK))
 574                 {
 575                         r = fw3_ipt_rule_create(handle, NULL, loopback_dev ? NULL : dev, NULL, sub, NULL);
 576                         fw3_ipt_rule_comment(r, "%s CT bypass", zone->name);
 577                         fw3_ipt_rule_target(r, "zone_%s_notrack", zone->name);
 578                         fw3_ipt_rule_extra(r, zone->extra_src);
 579                         fw3_ipt_rule_replace(r, chain);
 580                 }
 581         }
 582 }
 583
 584 static void
 585 print_interface_rules(struct fw3_ipt_handle *handle, struct fw3_state *state,
 586                       bool reload, struct fw3_zone *zone)
 587 {
 588         struct fw3_device *dev;
 589         struct fw3_address *sub;
 590
 591         fw3_foreach(dev, &zone->devices)
 592         fw3_foreach(sub, &zone->subnets)
 593         {
 594                 if (!fw3_is_family(sub, handle->family))
 595                         continue;
 596
 597                 if (!dev && !sub && !zone->extra_src && !zone->extra_dest)
 598                         continue;
 599
 600                 print_interface_rule(handle, state, reload, zone, dev, sub);
 601         }
 602 }
 603
 604 static struct fw3_address *
 605 next_addr(struct fw3_address *addr, struct list_head *list,
 606                 enum fw3_family family, bool invert)
 607 {
 608         struct list_head *p;
 609         struct fw3_address *rv;
 610
 611         for (p = addr ? addr->list.next : list->next; p != list; p = p->next)
 612         {
 613                 rv = list_entry(p, struct fw3_address, list);
 614
 615                 if (fw3_is_family(rv, family) && rv->set && rv->invert == invert)
 616                         return rv;
 617         }
 618
 619         return NULL;
 620 }
 621
 622 static void
 623 print_zone_rule(struct fw3_ipt_handle *handle, struct fw3_state *state,
 624                 bool reload, struct fw3_zone *zone)
 625 {
 626         bool first_src, first_dest;
 627         struct fw3_address *msrc;
 628         struct fw3_address *mdest;
 629         struct fw3_ipt_rule *r;
 630
 631         if (!fw3_is_family(zone, handle->family))
 632                 return;
 633
 634         info("   * Zone '%s'", zone->name);
 635
 636         switch (handle->table)
 637         {
 638         case FW3_TABLE_FILTER:
 639                 if (has(zone->flags, handle->family, FW3_FLAG_DNAT))
 640                 {
 641                         r = fw3_ipt_rule_new(handle);
 642                         fw3_ipt_rule_extra(r, "-m conntrack --ctstate DNAT");
 643                         fw3_ipt_rule_comment(r, "Accept port redirections");
 644                         fw3_ipt_rule_target(r, fw3_flag_names[FW3_FLAG_ACCEPT]);
 645                         fw3_ipt_rule_append(r, "zone_%s_input", zone->name);
 646
 647                         r = fw3_ipt_rule_new(handle);
 648                         fw3_ipt_rule_extra(r, "-m conntrack --ctstate DNAT");
 649                         fw3_ipt_rule_comment(r, "Accept port forwards");
 650                         fw3_ipt_rule_target(r, fw3_flag_names[FW3_FLAG_ACCEPT]);
 651                         fw3_ipt_rule_append(r, "zone_%s_forward", zone->name);
 652                 }
 653
 654                 r = fw3_ipt_rule_new(handle);
 655                 fw3_ipt_rule_target(r, "zone_%s_src_%s", zone->name,
 656                                      fw3_flag_names[zone->policy_input]);
 657                 fw3_ipt_rule_append(r, "zone_%s_input", zone->name);
 658
 659                 r = fw3_ipt_rule_new(handle);
 660                 fw3_ipt_rule_target(r, "zone_%s_dest_%s", zone->name,
 661                                      fw3_flag_names[zone->policy_forward]);
 662                 fw3_ipt_rule_append(r, "zone_%s_forward", zone->name);
 663
 664                 r = fw3_ipt_rule_new(handle);
 665                 fw3_ipt_rule_target(r, "zone_%s_dest_%s", zone->name,
 666                                      fw3_flag_names[zone->policy_output]);
 667                 fw3_ipt_rule_append(r, "zone_%s_output", zone->name);
 668
 669                 break;
 670
 671         case FW3_TABLE_NAT:
 672                 if (zone->masq && handle->family == FW3_FAMILY_V4)
 673                 {
 674                         /* for any negated masq_src ip, emit -s addr -j RETURN rules */
 675                         for (msrc = NULL;
 676                              (msrc = next_addr(msrc, &zone->masq_src,
 677                                                handle->family, true)) != NULL; )
 678                         {
 679                                 msrc->invert = false;
 680                                 r = fw3_ipt_rule_new(handle);
 681                                 fw3_ipt_rule_src_dest(r, msrc, NULL);
 682                                 fw3_ipt_rule_target(r, "RETURN");
 683                                 fw3_ipt_rule_append(r, "zone_%s_postrouting", zone->name);
 684                                 msrc->invert = true;
 685                         }
 686
 687                         /* for any negated masq_dest ip, emit -d addr -j RETURN rules */
 688                         for (mdest = NULL;
 689                              (mdest = next_addr(mdest, &zone->masq_dest,
 690                                                 handle->family, true)) != NULL; )
 691                         {
 692                                 mdest->invert = false;
 693                                 r = fw3_ipt_rule_new(handle);
 694                                 fw3_ipt_rule_src_dest(r, NULL, mdest);
 695                                 fw3_ipt_rule_target(r, "RETURN");
 696                                 fw3_ipt_rule_append(r, "zone_%s_postrouting", zone->name);
 697                                 mdest->invert = true;
 698                         }
 699
 700                         /* emit masquerading entries for non-negated addresses
 701                            and ensure that both src and dest loops run at least once,
 702                            even if there are no relevant addresses */
 703                         for (first_src = true, msrc = NULL;
 704                              (msrc = next_addr(msrc, &zone->masq_src,
 705                                                    handle->family, false)) || first_src;
 706                              first_src = false)
 707                         {
 708                                 for (first_dest = true, mdest = NULL;
 709                                      (mdest = next_addr(mdest, &zone->masq_dest,
 710                                                             handle->family, false)) || first_dest;
 711                                      first_dest = false)
 712                                 {
 713                                         r = fw3_ipt_rule_new(handle);
 714                                         fw3_ipt_rule_src_dest(r, msrc, mdest);
 715                                         fw3_ipt_rule_target(r, "MASQUERADE");
 716                                         fw3_ipt_rule_append(r, "zone_%s_postrouting", zone->name);
 717                                 }
 718                         }
 719                 }
 720                 break;
 721
 722         case FW3_TABLE_RAW:
 723                 fw3_print_cthelpers(handle, state, zone);
 724                 break;
 725
 726         case FW3_TABLE_MANGLE:
 727                 break;
 728         }
 729
 730         print_interface_rules(handle, state, reload, zone);
 731 }
 732
 733 void
 734 fw3_print_zone_chains(struct fw3_ipt_handle *handle, struct fw3_state *state,
 735                       bool reload)
 736 {
 737         struct fw3_zone *zone;
 738
 739         list_for_each_entry(zone, &state->zones, list)
 740                 print_zone_chain(handle, state, reload, zone);
 741 }
 742
 743 void
 744 fw3_print_zone_rules(struct fw3_ipt_handle *handle, struct fw3_state *state,
 745                      bool reload)
 746 {
 747         struct fw3_zone *zone;
 748
 749         list_for_each_entry(zone, &state->zones, list)
 750                 print_zone_rule(handle, state, reload, zone);
 751 }
 752
 753 void
 754 fw3_flush_zones(struct fw3_ipt_handle *handle, struct fw3_state *state,
 755                 bool reload)
 756 {
 757         struct fw3_zone *z, *tmp;
 758         const struct fw3_chain_spec *c;
 759         char chain[32];
 760
 761         list_for_each_entry_safe(z, tmp, &state->zones, list)
 762         {
 763                 if (!has(z->flags, handle->family, handle->table))
 764                         continue;
 765
 766                 for (c = zone_chains; c->format; c++)
 767                 {
 768                         /* don't touch user chains on selective stop */
 769                         if (reload && c->flag == FW3_FLAG_CUSTOM_CHAINS)
 770                                 continue;
 771
 772                         if (!fw3_is_family(c, handle->family))
 773                                 continue;
 774
 775                         if (c->table != handle->table)
 776                                 continue;
 777
 778                         if (c->flag && !has(z->flags, handle->family, c->flag))
 779                                 continue;
 780
 781                         snprintf(chain, sizeof(chain), c->format, z->name);
 782                         fw3_ipt_flush_chain(handle, chain);
 783
 784                         /* keep certain basic chains that do not depend on any settings to
 785                            avoid purging unrelated user rules pointing to them */
 786                         if (reload && !c->flag)
 787                                 continue;
 788
 789                         fw3_ipt_delete_chain(handle, chain);
 790                 }
 791
 792                 del(z->flags, handle->family, handle->table);
 793         }
 794 }
 795
 796 void
 797 fw3_hotplug_zones(struct fw3_state *state, bool add)
 798 {
 799         struct fw3_zone *z;
 800         struct fw3_device *d;
 801
 802         list_for_each_entry(z, &state->zones, list)
 803         {
 804                 if (add != fw3_hasbit(z->flags[0], FW3_FLAG_HOTPLUG))
 805                 {
 806                         list_for_each_entry(d, &z->devices, list)
 807                                 fw3_hotplug(add, z, d);
 808
 809                         if (add)
 810                                 fw3_setbit(z->flags[0], FW3_FLAG_HOTPLUG);
 811                         else
 812                                 fw3_delbit(z->flags[0], FW3_FLAG_HOTPLUG);
 813                 }
 814         }
 815 }
 816
 817 struct fw3_zone *
 818 fw3_lookup_zone(struct fw3_state *state, const char *name)
 819 {
 820         struct fw3_zone *z;
 821
 822         if (list_empty(&state->zones))
 823                 return NULL;
 824
 825         list_for_each_entry(z, &state->zones, list)
 826         {
 827                 if (strcmp(z->name, name))
 828                         continue;
 829
 830                 return z;
 831         }
 832
 833         return NULL;
 834 }
 835
 836 struct list_head *
 837 fw3_resolve_zone_addresses(struct fw3_zone *zone, struct fw3_address *addr)
 838 {
 839         struct fw3_device *net;
 840         struct fw3_address *cur, *tmp;
 841         struct list_head *all;
 842
 843         all = calloc(1, sizeof(*all));
 844         if (!all)
 845                 return NULL;
 846
 847         INIT_LIST_HEAD(all);
 848
 849         if (addr && addr->set)
 850         {
 851                 tmp = malloc(sizeof(*tmp));
 852
 853                 if (tmp)
 854                 {
 855                         *tmp = *addr;
 856                         list_add_tail(&tmp->list, all);
 857                 }
 858         }
 859         else
 860         {
 861                 list_for_each_entry(net, &zone->networks, list)
 862                         fw3_ubus_address(all, net->name);
 863
 864                 list_for_each_entry(cur, &zone->subnets, list)
 865                 {
 866                         tmp = malloc(sizeof(*tmp));
 867
 868                         if (!tmp)
 869                                 continue;
 870
 871                         *tmp = *cur;
 872                         list_add_tail(&tmp->list, all);
 873                 }
 874         }
 875
 876         return all;
 877 }