options.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 "options.h"
  20
  21 const char *fw3_flag_names[FW3_DEFAULT_DROP_INVALID + 1] = {
  22         "filter",
  23         "nat",
  24         "mangle",
  25         "raw",
  26
  27         "IPv4",
  28         "IPv6",
  29
  30         "ACCEPT",
  31         "REJECT",
  32         "DROP",
  33         "NOTRACK",
  34         "DNAT",
  35         "SNAT",
  36 };
  37
  38 bool
  39 fw3_parse_bool(void *ptr, const char *val)
  40 {
  41         if (!strcmp(val, "true") || !strcmp(val, "yes") || !strcmp(val, "1"))
  42                 *((bool *)ptr) = true;
  43         else
  44                 *((bool *)ptr) = false;
  45
  46         return true;
  47 }
  48
  49 bool
  50 fw3_parse_int(void *ptr, const char *val)
  51 {
  52         int n = strtol(val, NULL, 10);
  53
  54         if (errno == ERANGE || errno == EINVAL)
  55                 return false;
  56
  57         *((int *)ptr) = n;
  58
  59         return true;
  60 }
  61
  62 bool
  63 fw3_parse_string(void *ptr, const char *val)
  64 {
  65         *((char **)ptr) = (char *)val;
  66         return true;
  67 }
  68
  69 bool
  70 fw3_parse_target(void *ptr, const char *val)
  71 {
  72         if (!strcmp(val, "ACCEPT"))
  73         {
  74                 *((enum fw3_target *)ptr) = FW3_TARGET_ACCEPT;
  75                 return true;
  76         }
  77         else if (!strcmp(val, "REJECT"))
  78         {
  79                 *((enum fw3_target *)ptr) = FW3_TARGET_REJECT;
  80                 return true;
  81         }
  82         else if (!strcmp(val, "DROP"))
  83         {
  84                 *((enum fw3_target *)ptr) = FW3_TARGET_DROP;
  85                 return true;
  86         }
  87         else if (!strcmp(val, "NOTRACK"))
  88         {
  89                 *((enum fw3_target *)ptr) = FW3_TARGET_NOTRACK;
  90                 return true;
  91         }
  92         else if (!strcmp(val, "DNAT"))
  93         {
  94                 *((enum fw3_target *)ptr) = FW3_TARGET_DNAT;
  95                 return true;
  96         }
  97         else if (!strcmp(val, "SNAT"))
  98         {
  99                 *((enum fw3_target *)ptr) = FW3_TARGET_SNAT;
 100                 return true;
 101         }
 102
 103         return false;
 104 }
 105
 106 bool
 107 fw3_parse_limit(void *ptr, const char *val)
 108 {
 109         struct fw3_limit *limit = ptr;
 110         enum fw3_limit_unit u = FW3_LIMIT_UNIT_SECOND;
 111         char *e;
 112         int n;
 113
 114         if (*val == '!')
 115         {
 116                 limit->invert = true;
 117                 while (isspace(*++val));
 118         }
 119
 120         n = strtol(val, &e, 10);
 121
 122         if (errno == ERANGE || errno == EINVAL)
 123                 return false;
 124
 125         if (*e && *e++ != '/')
 126                 return false;
 127
 128         if (!strlen(e))
 129                 return false;
 130
 131         if (!strncmp(e, "second", strlen(e)))
 132                 u = FW3_LIMIT_UNIT_SECOND;
 133         else if (!strncmp(e, "minute", strlen(e)))
 134                 u = FW3_LIMIT_UNIT_MINUTE;
 135         else if (!strncmp(e, "hour", strlen(e)))
 136                 u = FW3_LIMIT_UNIT_HOUR;
 137         else if (!strncmp(e, "day", strlen(e)))
 138                 u = FW3_LIMIT_UNIT_DAY;
 139         else
 140                 return false;
 141
 142         limit->rate = n;
 143         limit->unit = u;
 144
 145         return true;
 146 }
 147
 148 bool
 149 fw3_parse_device(void *ptr, const char *val)
 150 {
 151         struct fw3_device *dev = ptr;
 152
 153         if (*val == '*')
 154         {
 155                 dev->set = true;
 156                 dev->any = true;
 157                 return true;
 158         }
 159
 160         if (*val == '!')
 161         {
 162                 dev->invert = true;
 163                 while (isspace(*++val));
 164         }
 165
 166         if (*val)
 167                 snprintf(dev->name, sizeof(dev->name), "%s", val);
 168         else
 169                 return false;
 170
 171         dev->set = true;
 172         return true;
 173 }
 174
 175 bool
 176 fw3_parse_address(void *ptr, const char *val)
 177 {
 178         struct fw3_address *addr = ptr;
 179         struct in_addr v4;
 180         struct in6_addr v6;
 181         char *p, *s, *e;
 182         int i, m = -1;
 183
 184         if (*val == '!')
 185         {
 186                 addr->invert = true;
 187                 while (isspace(*++val));
 188         }
 189
 190         s = strdup(val);
 191
 192         if (!s)
 193                 return false;
 194
 195         if ((p = strchr(s, '/')) != NULL)
 196         {
 197                 *p++ = 0;
 198                 m = strtoul(p, &e, 10);
 199
 200                 if ((e == p) || (*e != 0))
 201                 {
 202                         if (strchr(s, ':') || !inet_pton(AF_INET, p, &v4))
 203                         {
 204                                 free(s);
 205                                 return false;
 206                         }
 207
 208                         for (i = 0, m = 32; !(v4.s_addr & 1) && (i < 32); i++)
 209                         {
 210                                 m--;
 211                                 v4.s_addr >>= 1;
 212                         }
 213                 }
 214         }
 215
 216         if (inet_pton(AF_INET6, s, &v6))
 217         {
 218                 addr->family = FW3_FAMILY_V6;
 219                 addr->address.v6 = v6;
 220                 addr->mask = (m >= 0) ? m : 128;
 221         }
 222         else if (inet_pton(AF_INET, s, &v4))
 223         {
 224                 addr->family = FW3_FAMILY_V4;
 225                 addr->address.v4 = v4;
 226                 addr->mask = (m >= 0) ? m : 32;
 227         }
 228         else
 229         {
 230                 free(s);
 231                 return false;
 232         }
 233
 234         free(s);
 235         addr->set = true;
 236         return true;
 237 }
 238
 239 bool
 240 fw3_parse_mac(void *ptr, const char *val)
 241 {
 242         struct fw3_mac *addr = ptr;
 243         struct ether_addr *mac;
 244
 245         if (*val == '!')
 246         {
 247                 addr->invert = true;
 248                 while (isspace(*++val));
 249         }
 250
 251         if ((mac = ether_aton(val)) != NULL)
 252         {
 253                 addr->mac = *mac;
 254                 addr->set = true;
 255                 return true;
 256         }
 257
 258         return false;
 259 }
 260
 261 bool
 262 fw3_parse_port(void *ptr, const char *val)
 263 {
 264         struct fw3_port *range = ptr;
 265         uint16_t n;
 266         uint16_t m;
 267         char *p;
 268
 269         if (*val == '!')
 270         {
 271                 range->invert = true;
 272                 while (isspace(*++val));
 273         }
 274
 275         n = strtoul(val, &p, 10);
 276
 277         if (errno == ERANGE || errno == EINVAL)
 278                 return false;
 279
 280         if (*p && *p != '-' && *p != ':')
 281                 return false;
 282
 283         if (*p)
 284         {
 285                 m = strtoul(++p, NULL, 10);
 286
 287                 if (errno == ERANGE || errno == EINVAL || m < n)
 288                         return false;
 289
 290                 range->port_min = n;
 291                 range->port_max = m;
 292         }
 293         else
 294         {
 295                 range->port_min = n;
 296                 range->port_max = n;
 297         }
 298
 299         range->set = true;
 300         return true;
 301 }
 302
 303 bool
 304 fw3_parse_family(void *ptr, const char *val)
 305 {
 306         if (!strcmp(val, "any"))
 307                 *((enum fw3_family *)ptr) = FW3_FAMILY_ANY;
 308         else if (!strcmp(val, "inet") || strrchr(val, '4'))
 309                 *((enum fw3_family *)ptr) = FW3_FAMILY_V4;
 310         else if (!strcmp(val, "inet6") || strrchr(val, '6'))
 311                 *((enum fw3_family *)ptr) = FW3_FAMILY_V6;
 312         else
 313                 return false;
 314
 315         return true;
 316 }
 317
 318 bool
 319 fw3_parse_icmptype(void *ptr, const char *val)
 320 {
 321         struct fw3_icmptype *icmp = ptr;
 322         bool v4 = false;
 323         bool v6 = false;
 324         char *p;
 325         int i;
 326
 327         for (i = 0; i < ARRAY_SIZE(fw3_icmptype_list_v4); i++)
 328         {
 329                 if (!strcmp(val, fw3_icmptype_list_v4[i].name))
 330                 {
 331                         icmp->type     = fw3_icmptype_list_v4[i].type;
 332                         icmp->code_min = fw3_icmptype_list_v4[i].code_min;
 333                         icmp->code_max = fw3_icmptype_list_v4[i].code_max;
 334
 335                         v4 = true;
 336                         break;
 337                 }
 338         }
 339
 340         for (i = 0; i < ARRAY_SIZE(fw3_icmptype_list_v6); i++)
 341         {
 342                 if (!strcmp(val, fw3_icmptype_list_v6[i].name))
 343                 {
 344                         icmp->type6     = fw3_icmptype_list_v6[i].type;
 345                         icmp->code6_min = fw3_icmptype_list_v6[i].code_min;
 346                         icmp->code6_max = fw3_icmptype_list_v6[i].code_max;
 347
 348                         v6 = true;
 349                         break;
 350                 }
 351         }
 352
 353         if (!v4 && !v6)
 354         {
 355                 i = strtoul(val, &p, 10);
 356
 357                 if ((p == val) || (*p != '/' && *p != 0) || (i > 0xFF))
 358                         return false;
 359
 360                 icmp->type = i;
 361
 362                 if (*p == '/')
 363                 {
 364                         val = ++p;
 365                         i = strtoul(val, &p, 10);
 366
 367                         if ((p == val) || (*p != 0) || (i > 0xFF))
 368                                 return false;
 369
 370                         icmp->code_min = i;
 371                         icmp->code_max = i;
 372                 }
 373                 else
 374                 {
 375                         icmp->code_min = 0;
 376                         icmp->code_max = 0xFF;
 377                 }
 378
 379                 icmp->type6     = icmp->type;
 380                 icmp->code6_min = icmp->code_max;
 381                 icmp->code6_max = icmp->code_max;
 382
 383                 v4 = true;
 384                 v6 = true;
 385         }
 386
 387         icmp->family = (v4 && v6) ? FW3_FAMILY_ANY
 388                                   : (v6 ? FW3_FAMILY_V6 : FW3_FAMILY_V4);
 389
 390         return true;
 391 }
 392
 393 bool
 394 fw3_parse_protocol(void *ptr, const char *val)
 395 {
 396         struct fw3_protocol *proto = ptr;
 397         struct protoent *ent;
 398
 399         if (*val == '!')
 400         {
 401                 proto->invert = true;
 402                 while (isspace(*++val));
 403         }
 404
 405         if (!strcmp(val, "all"))
 406         {
 407                 proto->any = true;
 408                 return true;
 409         }
 410         else if (!strcmp(val, "icmpv6"))
 411         {
 412                 val = "ipv6-icmp";
 413         }
 414
 415         ent = getprotobyname(val);
 416
 417         if (ent)
 418         {
 419                 proto->protocol = ent->p_proto;
 420                 return true;
 421         }
 422
 423         proto->protocol = strtoul(val, NULL, 10);
 424         return (errno != ERANGE && errno != EINVAL);
 425 }
 426
 427 bool
 428 fw3_parse_ipset_method(void *ptr, const char *val)
 429 {
 430         if (!strncmp(val, "bitmap", strlen(val)))
 431         {
 432                 *((enum fw3_ipset_method *)ptr) = FW3_IPSET_METHOD_BITMAP;
 433                 return true;
 434         }
 435         else if (!strncmp(val, "hash", strlen(val)))
 436         {
 437                 *((enum fw3_ipset_method *)ptr) = FW3_IPSET_METHOD_HASH;
 438                 return true;
 439         }
 440         else if (!strncmp(val, "list", strlen(val)))
 441         {
 442                 *((enum fw3_ipset_method *)ptr) = FW3_IPSET_METHOD_LIST;
 443                 return true;
 444         }
 445
 446         return false;
 447 }
 448
 449 bool
 450 fw3_parse_ipset_datatype(void *ptr, const char *val)
 451 {
 452         struct fw3_ipset_datatype *type = ptr;
 453
 454         if (!strncmp(val, "dest_", 5))
 455         {
 456                 val += 5;
 457                 type->dest = true;
 458         }
 459         else if (!strncmp(val, "dst_", 4))
 460         {
 461                 val += 4;
 462                 type->dest = true;
 463         }
 464         else if (!strncmp(val, "src_", 4))
 465         {
 466                 val += 4;
 467                 type->dest = false;
 468         }
 469
 470         if (!strncmp(val, "ip", strlen(val)))
 471         {
 472                 type->type = FW3_IPSET_TYPE_IP;
 473                 return true;
 474         }
 475         else if (!strncmp(val, "port", strlen(val)))
 476         {
 477                 type->type = FW3_IPSET_TYPE_PORT;
 478                 return true;
 479         }
 480         else if (!strncmp(val, "mac", strlen(val)))
 481         {
 482                 type->type = FW3_IPSET_TYPE_MAC;
 483                 return true;
 484         }
 485         else if (!strncmp(val, "net", strlen(val)))
 486         {
 487                 type->type = FW3_IPSET_TYPE_NET;
 488                 return true;
 489         }
 490         else if (!strncmp(val, "set", strlen(val)))
 491         {
 492                 type->type = FW3_IPSET_TYPE_SET;
 493                 return true;
 494         }
 495
 496         return false;
 497 }
 498
 499
 500 void
 501 fw3_parse_options(void *s, const struct fw3_option *opts,
 502                   struct uci_section *section)
 503 {
 504         char *p;
 505         bool known;
 506         struct uci_element *e, *l;
 507         struct uci_option *o;
 508         const struct fw3_option *opt;
 509         struct list_head *item;
 510         struct list_head *dest;
 511
 512         uci_foreach_element(&section->options, e)
 513         {
 514                 o = uci_to_option(e);
 515                 known = false;
 516
 517                 for (opt = opts; opt->name; opt++)
 518                 {
 519                         if (!opt->parse)
 520                                 continue;
 521
 522                         if (strcmp(opt->name, e->name))
 523                                 continue;
 524
 525                         if (o->type == UCI_TYPE_LIST)
 526                         {
 527                                 if (!opt->elem_size)
 528                                 {
 529                                         warn_elem(e, "must not be a list");
 530                                 }
 531                                 else
 532                                 {
 533                                         uci_foreach_element(&o->v.list, l)
 534                                         {
 535                                                 if (!l->name)
 536                                                         continue;
 537
 538                                                 item = malloc(opt->elem_size);
 539
 540                                                 if (!item)
 541                                                         continue;
 542
 543                                                 memset(item, 0, opt->elem_size);
 544
 545                                                 if (!opt->parse(item, l->name))
 546                                                 {
 547                                                         warn_elem(e, "has invalid value '%s'", l->name);
 548                                                         free(item);
 549                                                         continue;
 550                                                 }
 551
 552                                                 dest = (struct list_head *)((char *)s + opt->offset);
 553                                                 list_add_tail(item, dest);
 554                                         }
 555                                 }
 556                         }
 557                         else
 558                         {
 559                                 if (!o->v.string)
 560                                         continue;
 561
 562                                 if (!opt->elem_size)
 563                                 {
 564                                         if (!opt->parse((char *)s + opt->offset, o->v.string))
 565                                                 warn_elem(e, "has invalid value '%s'", o->v.string);
 566                                 }
 567                                 else
 568                                 {
 569                                         for (p = strtok(o->v.string, " \t");
 570                                              p != NULL;
 571                                              p = strtok(NULL, " \t"))
 572                                         {
 573                                                 item = malloc(opt->elem_size);
 574
 575                                                 if (!item)
 576                                                         continue;
 577
 578                                                 memset(item, 0, opt->elem_size);
 579
 580                                                 if (!opt->parse(item, p))
 581                                                 {
 582                                                         warn_elem(e, "has invalid value '%s'", p);
 583                                                         free(item);
 584                                                         continue;
 585                                                 }
 586
 587                                                 dest = (struct list_head *)((char *)s + opt->offset);
 588                                                 list_add_tail(item, dest);
 589                                         }
 590                                 }
 591                         }
 592
 593                         known = true;
 594                         break;
 595                 }
 596
 597                 if (!known)
 598                         warn_elem(e, "is unknown");
 599         }
 600 }
 601
 602
 603 void
 604 fw3_format_in_out(struct fw3_device *in, struct fw3_device *out)
 605 {
 606         if (in && !in->any)
 607                 fw3_pr(" %s-i %s", in->invert ? "! " : "", in->name);
 608
 609         if (out && !out->any)
 610                 fw3_pr(" %s-o %s", out->invert ? "! " : "", out->name);
 611 }
 612
 613 void
 614 fw3_format_src_dest(struct fw3_address *src, struct fw3_address *dest)
 615 {
 616         char s[INET6_ADDRSTRLEN];
 617
 618         if (src && src->set)
 619         {
 620                 inet_ntop(src->family == FW3_FAMILY_V4 ? AF_INET : AF_INET6,
 621                           &src->address.v4, s, sizeof(s));
 622
 623                 fw3_pr(" %s-s %s/%u", src->invert ? "! " : "", s, src->mask);
 624         }
 625
 626         if (dest && dest->set)
 627         {
 628                 inet_ntop(dest->family == FW3_FAMILY_V4 ? AF_INET : AF_INET6,
 629                           &dest->address.v4, s, sizeof(s));
 630
 631                 fw3_pr(" %s-d %s/%u", dest->invert ? "! " : "", s, dest->mask);
 632         }
 633 }
 634
 635 void
 636 fw3_format_sport_dport(struct fw3_port *sp, struct fw3_port *dp)
 637 {
 638         if (sp && sp->set)
 639         {
 640                 if (sp->port_min == sp->port_max)
 641                         fw3_pr(" %s--sport %u", sp->invert ? "! " : "", sp->port_min);
 642                 else
 643                         fw3_pr(" %s--sport %u:%u",
 644                                sp->invert ? "! " : "", sp->port_min, sp->port_max);
 645         }
 646
 647         if (dp && dp->set)
 648         {
 649                 if (dp->port_min == dp->port_max)
 650                         fw3_pr(" %s--dport %u", dp->invert ? "! " : "", dp->port_min);
 651                 else
 652                         fw3_pr(" %s--dport %u:%u",
 653                                dp->invert ? "! " : "", dp->port_min, dp->port_max);
 654         }
 655 }
 656
 657 void
 658 fw3_format_mac(struct fw3_mac *mac)
 659 {
 660         if (!mac)
 661                 return;
 662
 663         fw3_pr(" -m mac %s--mac-source %s",
 664                mac->invert ? "! " : "", ether_ntoa(&mac->mac));
 665 }
 666
 667 void
 668 fw3_format_protocol(struct fw3_protocol *proto, enum fw3_family family)
 669 {
 670         uint16_t pr;
 671
 672         if (!proto)
 673                 return;
 674
 675         pr = proto->protocol;
 676
 677         if (pr == 1 && family == FW3_FAMILY_V6)
 678                 pr = 58;
 679
 680         if (proto->any)
 681                 fw3_pr(" -p all");
 682         else
 683                 fw3_pr(" %s-p %u", proto->invert ? "! " : "", pr);
 684 }
 685
 686 void
 687 fw3_format_icmptype(struct fw3_icmptype *icmp, enum fw3_family family)
 688 {
 689         if (!icmp)
 690                 return;
 691
 692         if (family != FW3_FAMILY_V6)
 693         {
 694                 if (icmp->code_min == 0 && icmp->code_max == 0xFF)
 695                         fw3_pr(" %s--icmp-type %u", icmp->invert ? "! " : "", icmp->type);
 696                 else
 697                         fw3_pr(" %s--icmp-type %u/%u",
 698                                    icmp->invert ? "! " : "", icmp->type, icmp->code_min);
 699         }
 700         else
 701         {
 702                 if (icmp->code6_min == 0 && icmp->code6_max == 0xFF)
 703                         fw3_pr(" %s--icmpv6-type %u", icmp->invert ? "! " : "", icmp->type6);
 704                 else
 705                         fw3_pr(" %s--icmpv6-type %u/%u",
 706                                    icmp->invert ? "! " : "", icmp->type6, icmp->code6_min);
 707         }
 708 }
 709
 710 void
 711 fw3_format_limit(struct fw3_limit *limit)
 712 {
 713         if (!limit)
 714                 return;
 715
 716         const char *units[] = {
 717                 [FW3_LIMIT_UNIT_SECOND] = "second",
 718                 [FW3_LIMIT_UNIT_MINUTE] = "minute",
 719                 [FW3_LIMIT_UNIT_HOUR]   = "hour",
 720                 [FW3_LIMIT_UNIT_DAY]    = "day",
 721         };
 722
 723         if (limit->rate > 0)
 724         {
 725                 fw3_pr(" -m limit %s--limit %u/%s",
 726                        limit->invert ? "! " : "", limit->rate, units[limit->unit]);
 727
 728                 if (limit->burst > 0)
 729                         fw3_pr(" --limit-burst %u", limit->burst);
 730         }
 731 }
 732
 733 void
 734 fw3_format_ipset(struct fw3_ipset *ipset, bool invert)
 735 {
 736         bool first = true;
 737         const char *name = NULL;
 738         struct fw3_ipset_datatype *type;
 739
 740         if (!ipset)
 741                 return;
 742
 743         if (ipset->external && *ipset->external)
 744                 name = ipset->external;
 745         else
 746                 name = ipset->name;
 747
 748         fw3_pr(" -m set %s--match-set %s", invert ? "! " : "", name);
 749
 750         list_for_each_entry(type, &ipset->datatypes, list)
 751         {
 752                 fw3_pr("%c%s", first ? ' ' : ',', type->dest ? "dst" : "src");
 753                 first = false;
 754         }
 755 }
 756
 757 void
 758 __fw3_format_comment(const char *comment, ...)
 759 {
 760         va_list ap;
 761         int len = 0;
 762         const char *c;
 763
 764         if (!comment || !*comment)
 765                 return;
 766
 767         fw3_pr(" -m comment --comment \"");
 768
 769         c = comment;
 770
 771         va_start(ap, comment);
 772
 773         do
 774         {
 775                 while (*c)
 776                 {
 777                         switch (*c)
 778                         {
 779                         case '"':
 780                         case '$':
 781                         case '`':
 782                         case '\\':
 783                                 fw3_pr("\\");
 784                                 /* fall through */
 785
 786                         default:
 787                                 fw3_pr("%c", *c);
 788                                 break;
 789                         }
 790
 791                         c++;
 792
 793                         if (len++ >= 255)
 794                                 goto end;
 795                 }
 796
 797                 c = va_arg(ap, const char *);
 798         }
 799         while (c);
 800
 801 end:
 802         va_end(ap);
 803         fw3_pr("\"");
 804 }
 805
 806 void
 807 fw3_format_extra(const char *extra)
 808 {
 809         if (!extra || !*extra)
 810                 return;
 811
 812         fw3_pr(" %s", extra);
 813 }