iptables.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 "iptables.h"
  20
  21
  22 static struct option base_opts[] = {
  23         { .name = "match",  .has_arg = 1, .val = 'm' },
  24         { .name = "jump",   .has_arg = 1, .val = 'j' },
  25         { .name = "append", .has_arg = 1, .val = 'A' },
  26         { NULL }
  27 };
  28
  29 static struct xtables_globals xtg = {
  30         .option_offset = 0,
  31         .program_version = "4",
  32         .orig_opts = base_opts,
  33 };
  34
  35 static struct xtables_globals xtg6 = {
  36         .option_offset = 0,
  37         .program_version = "6",
  38         .orig_opts = base_opts,
  39 };
  40
  41 /* Required by certain extensions like SNAT and DNAT */
  42 int kernel_version = 0;
  43
  44 void
  45 get_kernel_version(void)
  46 {
  47         static struct utsname uts;
  48         int x = 0, y = 0, z = 0;
  49
  50         if (uname(&uts) == -1)
  51                 sprintf(uts.release, "3.0.0");
  52
  53         sscanf(uts.release, "%d.%d.%d", &x, &y, &z);
  54         kernel_version = 0x10000 * x + 0x100 * y + z;
  55 }
  56
  57 #ifdef DISABLE_IPV6
  58 #undef __ipt_module
  59 #define __ipt_module(x) libxt_##x##_init, libipt_##x##_init,
  60 #else
  61 #undef __ipt_module
  62 #define __ipt_module(x) libxt_##x##_init, libipt_##x##_init, libip6t_##x##_init,
  63 #endif
  64
  65 static void fw3_init_extensions(void)
  66 {
  67         int i;
  68         void (*initfuncs[])(void) = { FW3_IPT_MODULES };
  69
  70         for (i = 0; i < sizeof(initfuncs)/sizeof(initfuncs[0]); i++)
  71                 if (initfuncs[i])
  72                         initfuncs[i]();
  73 }
  74
  75 struct fw3_ipt_handle *
  76 fw3_ipt_open(enum fw3_family family, enum fw3_table table)
  77 {
  78         struct fw3_ipt_handle *h;
  79
  80         h = fw3_alloc(sizeof(*h));
  81
  82         xtables_init();
  83
  84         if (family == FW3_FAMILY_V6)
  85         {
  86 #ifndef DISABLE_IPV6
  87                 h->family = FW3_FAMILY_V6;
  88                 h->table  = table;
  89                 h->handle = ip6tc_init(fw3_flag_names[table]);
  90
  91                 xtables_set_params(&xtg6);
  92                 xtables_set_nfproto(NFPROTO_IPV6);
  93 #endif
  94         }
  95         else
  96         {
  97                 h->family = FW3_FAMILY_V4;
  98                 h->table  = table;
  99                 h->handle = iptc_init(fw3_flag_names[table]);
 100
 101                 xtables_set_params(&xtg);
 102                 xtables_set_nfproto(NFPROTO_IPV4);
 103         }
 104
 105         if (!h->handle)
 106         {
 107                 free(h);
 108                 return NULL;
 109         }
 110
 111         fw3_xt_reset();
 112         fw3_init_extensions();
 113
 114         return h;
 115 }
 116
 117 static void
 118 debug(struct fw3_ipt_handle *h, const char *fmt, ...)
 119 {
 120         va_list ap;
 121
 122         printf("%s -t %s ", (h->family == FW3_FAMILY_V6) ? "ip6tables" : "iptables",
 123                             fw3_flag_names[h->table]);
 124
 125         va_start(ap, fmt);
 126         vprintf(fmt, ap);
 127         va_end(ap);
 128 }
 129
 130 void
 131 fw3_ipt_set_policy(struct fw3_ipt_handle *h, const char *chain,
 132                    enum fw3_flag policy)
 133 {
 134         if (fw3_pr_debug)
 135                 debug(h, "-P %s %s\n", chain, fw3_flag_names[policy]);
 136
 137 #ifndef DISABLE_IPV6
 138         if (h->family == FW3_FAMILY_V6)
 139                 ip6tc_set_policy(chain, fw3_flag_names[policy], NULL, h->handle);
 140         else
 141 #endif
 142                 iptc_set_policy(chain, fw3_flag_names[policy], NULL, h->handle);
 143 }
 144
 145 void
 146 fw3_ipt_delete_chain(struct fw3_ipt_handle *h, const char *chain)
 147 {
 148         if (fw3_pr_debug)
 149         {
 150                 debug(h, "-F %s\n", chain);
 151                 debug(h, "-X %s\n", chain);
 152         }
 153
 154 #ifndef DISABLE_IPV6
 155         if (h->family == FW3_FAMILY_V6)
 156         {
 157                 if (ip6tc_flush_entries(chain, h->handle))
 158                         ip6tc_delete_chain(chain, h->handle);
 159         }
 160         else
 161 #endif
 162         {
 163                 if (iptc_flush_entries(chain, h->handle))
 164                         iptc_delete_chain(chain, h->handle);
 165         }
 166 }
 167
 168 void
 169 fw3_ipt_delete_rules(struct fw3_ipt_handle *h, const char *target)
 170 {
 171         unsigned int num;
 172         const struct ipt_entry *e;
 173         const char *chain;
 174         const char *t;
 175         bool found;
 176
 177 #ifndef DISABLE_IPV6
 178         if (h->family == FW3_FAMILY_V6)
 179         {
 180                 for (chain = ip6tc_first_chain(h->handle);
 181                      chain != NULL;
 182                      chain = ip6tc_next_chain(h->handle))
 183                 {
 184                         do {
 185                                 found = false;
 186
 187                                 const struct ip6t_entry *e6;
 188                                 for (num = 0, e6 = ip6tc_first_rule(chain, h->handle);
 189                                          e6 != NULL;
 190                                          num++, e6 = ip6tc_next_rule(e6, h->handle))
 191                                 {
 192                                         t = ip6tc_get_target(e6, h->handle);
 193
 194                                         if (*t && !strcmp(t, target))
 195                                         {
 196                                                 if (fw3_pr_debug)
 197                                                         debug(h, "-D %s %u\n", chain, num + 1);
 198
 199                                                 ip6tc_delete_num_entry(chain, num, h->handle);
 200                                                 found = true;
 201                                                 break;
 202                                         }
 203                                 }
 204                         } while (found);
 205                 }
 206         }
 207         else
 208 #endif
 209         {
 210                 for (chain = iptc_first_chain(h->handle);
 211                      chain != NULL;
 212                      chain = iptc_next_chain(h->handle))
 213                 {
 214                         do {
 215                                 found = false;
 216
 217                                 for (num = 0, e = iptc_first_rule(chain, h->handle);
 218                                      e != NULL;
 219                                          num++, e = iptc_next_rule(e, h->handle))
 220                                 {
 221                                         t = iptc_get_target(e, h->handle);
 222
 223                                         if (*t && !strcmp(t, target))
 224                                         {
 225                                                 if (fw3_pr_debug)
 226                                                         debug(h, "-D %s %u\n", chain, num + 1);
 227
 228                                                 iptc_delete_num_entry(chain, num, h->handle);
 229                                                 found = true;
 230                                                 break;
 231                                         }
 232                                 }
 233                         } while (found);
 234                 }
 235         }
 236 }
 237
 238 void
 239 fw3_ipt_create_chain(struct fw3_ipt_handle *h, const char *fmt, ...)
 240 {
 241         char buf[32];
 242         va_list ap;
 243
 244         va_start(ap, fmt);
 245         vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
 246         va_end(ap);
 247
 248         if (fw3_pr_debug)
 249                 debug(h, "-N %s\n", buf);
 250
 251         iptc_create_chain(buf, h->handle);
 252 }
 253
 254 void
 255 fw3_ipt_flush(struct fw3_ipt_handle *h)
 256 {
 257         const char *chain;
 258
 259 #ifndef DISABLE_IPV6
 260         if (h->family == FW3_FAMILY_V6)
 261         {
 262                 for (chain = ip6tc_first_chain(h->handle);
 263                      chain != NULL;
 264                      chain = ip6tc_next_chain(h->handle))
 265                 {
 266                         ip6tc_flush_entries(chain, h->handle);
 267                 }
 268
 269                 for (chain = ip6tc_first_chain(h->handle);
 270                      chain != NULL;
 271                      chain = ip6tc_next_chain(h->handle))
 272                 {
 273                         ip6tc_delete_chain(chain, h->handle);
 274                 }
 275         }
 276         else
 277 #endif
 278         {
 279                 for (chain = iptc_first_chain(h->handle);
 280                      chain != NULL;
 281                      chain = iptc_next_chain(h->handle))
 282                 {
 283                         iptc_flush_entries(chain, h->handle);
 284                 }
 285
 286                 for (chain = iptc_first_chain(h->handle);
 287                      chain != NULL;
 288                      chain = iptc_next_chain(h->handle))
 289                 {
 290                         iptc_delete_chain(chain, h->handle);
 291                 }
 292         }
 293 }
 294
 295 void
 296 fw3_ipt_commit(struct fw3_ipt_handle *h)
 297 {
 298         int rv;
 299
 300 #ifndef DISABLE_IPV6
 301         if (h->family == FW3_FAMILY_V6)
 302         {
 303                 rv = ip6tc_commit(h->handle);
 304                 if (!rv)
 305                         fprintf(stderr, "ip6tc_commit(): %s\n", ip6tc_strerror(errno));
 306         }
 307         else
 308 #endif
 309         {
 310                 rv = iptc_commit(h->handle);
 311                 if (!rv)
 312                         fprintf(stderr, "iptc_commit(): %s\n", iptc_strerror(errno));
 313         }
 314 }
 315
 316 void
 317 fw3_ipt_close(struct fw3_ipt_handle *h)
 318 {
 319         if (h->libv)
 320         {
 321                 while (h->libc > 0)
 322                 {
 323                         h->libc--;
 324                         dlclose(h->libv[h->libc]);
 325                 }
 326
 327                 free(h->libv);
 328         }
 329
 330         free(h);
 331 }
 332
 333 struct fw3_ipt_rule *
 334 fw3_ipt_rule_new(struct fw3_ipt_handle *h)
 335 {
 336         struct fw3_ipt_rule *r;
 337
 338         r = fw3_alloc(sizeof(*r));
 339
 340         r->h = h;
 341         r->argv = fw3_alloc(sizeof(char *));
 342         r->argv[r->argc++] = "fw3";
 343
 344         return r;
 345 }
 346
 347
 348 static bool
 349 is_chain(struct fw3_ipt_handle *h, const char *name)
 350 {
 351 #ifndef DISABLE_IPV6
 352         if (h->family == FW3_FAMILY_V6)
 353                 return ip6tc_is_chain(name, h->handle);
 354         else
 355 #endif
 356                 return iptc_is_chain(name, h->handle);
 357 }
 358
 359 static char *
 360 get_protoname(struct fw3_ipt_rule *r)
 361 {
 362         const struct xtables_pprot *pp;
 363
 364         if (r->protocol)
 365                 for (pp = xtables_chain_protos; pp->name; pp++)
 366                         if (pp->num == r->protocol)
 367                                 return (char *)pp->name;
 368
 369         return NULL;
 370 }
 371
 372 static bool
 373 load_extension(struct fw3_ipt_handle *h, const char *name)
 374 {
 375         char path[256];
 376         void *lib, **tmp;
 377         const char *pfx = (h->family == FW3_FAMILY_V6) ? "libip6t" : "libipt";
 378
 379         snprintf(path, sizeof(path), "/usr/lib/iptables/libxt_%s.so", name);
 380         if (!(lib = dlopen(path, RTLD_NOW)))
 381         {
 382                 snprintf(path, sizeof(path), "/usr/lib/iptables/%s_%s.so", pfx, name);
 383                 lib = dlopen(path, RTLD_NOW);
 384         }
 385
 386         if (!lib)
 387                 return false;
 388
 389         tmp = realloc(h->libv, sizeof(lib) * (h->libc + 1));
 390
 391         if (!tmp)
 392                 return false;
 393
 394         h->libv = tmp;
 395         h->libv[h->libc++] = lib;
 396
 397         return true;
 398 }
 399
 400 static struct xtables_match *
 401 find_match(struct fw3_ipt_rule *r, const char *name)
 402 {
 403         struct xtables_match *m;
 404
 405         m = xtables_find_match(name, XTF_DONT_LOAD, &r->matches);
 406
 407         if (!m && load_extension(r->h, name))
 408                 m = xtables_find_match(name, XTF_DONT_LOAD, &r->matches);
 409
 410         return m;
 411 }
 412
 413 static void
 414 init_match(struct fw3_ipt_rule *r, struct xtables_match *m, bool no_clone)
 415 {
 416         size_t s;
 417         struct xtables_globals *g;
 418
 419         if (!m)
 420                 return;
 421
 422         s = XT_ALIGN(sizeof(struct xt_entry_match)) + m->size;
 423
 424         m->m = fw3_alloc(s);
 425
 426         fw3_xt_set_match_name(m);
 427
 428         m->m->u.user.revision = m->revision;
 429         m->m->u.match_size = s;
 430
 431         /* free previous userspace data */
 432         fw3_xt_free_match_udata(m);
 433
 434         if (m->init)
 435                 m->init(m->m);
 436
 437         /* don't merge options if no_clone is set and this match is a clone */
 438         if (no_clone && (m == m->next))
 439                 return;
 440
 441         /* merge option table */
 442         g = (r->h->family == FW3_FAMILY_V6) ? &xtg6 : &xtg;
 443         fw3_xt_merge_match_options(g, m);
 444 }
 445
 446 static bool
 447 need_protomatch(struct fw3_ipt_rule *r, const char *pname)
 448 {
 449         if (!pname)
 450                 return false;
 451
 452         if (!xtables_find_match(pname, XTF_DONT_LOAD, NULL))
 453                 return true;
 454
 455         return !r->protocol_loaded;
 456 }
 457
 458 static struct xtables_match *
 459 load_protomatch(struct fw3_ipt_rule *r)
 460 {
 461         const char *pname = get_protoname(r);
 462
 463         if (!need_protomatch(r, pname))
 464                 return NULL;
 465
 466         return find_match(r, pname);
 467 }
 468
 469 static struct xtables_target *
 470 find_target(struct fw3_ipt_rule *r, const char *name)
 471 {
 472         struct xtables_target *t;
 473
 474         if (is_chain(r->h, name))
 475                 return xtables_find_target(XT_STANDARD_TARGET, XTF_LOAD_MUST_SUCCEED);
 476
 477         t = xtables_find_target(name, XTF_DONT_LOAD);
 478
 479         if (!t && load_extension(r->h, name))
 480                 t = xtables_find_target(name, XTF_DONT_LOAD);
 481
 482         return t;
 483 }
 484
 485 static struct xtables_target *
 486 get_target(struct fw3_ipt_rule *r, const char *name)
 487 {
 488         size_t s;
 489         struct xtables_target *t;
 490         struct xtables_globals *g;
 491
 492         t = find_target(r, name);
 493
 494         if (!t)
 495                 return NULL;
 496
 497         s = XT_ALIGN(sizeof(struct xt_entry_target)) + t->size;
 498         t->t = fw3_alloc(s);
 499
 500         fw3_xt_set_target_name(t, name);
 501
 502         t->t->u.user.revision = t->revision;
 503         t->t->u.target_size = s;
 504
 505         /* free previous userspace data */
 506         fw3_xt_free_target_udata(t);
 507
 508         if (t->init)
 509                 t->init(t->t);
 510
 511         /* merge option table */
 512         g = (r->h->family == FW3_FAMILY_V6) ? &xtg6 : &xtg;
 513         fw3_xt_merge_target_options(g, t);
 514
 515         r->target = t;
 516
 517         return t;
 518 }
 519
 520 void
 521 fw3_ipt_rule_proto(struct fw3_ipt_rule *r, struct fw3_protocol *proto)
 522 {
 523         uint32_t pr;
 524
 525         if (!proto || proto->any)
 526                 return;
 527
 528         pr = proto->protocol;
 529
 530 #ifndef DISABLE_IPV6
 531         if (r->h->family == FW3_FAMILY_V6)
 532         {
 533                 if (pr == 1)
 534                         pr = 58;
 535
 536                 r->e6.ipv6.proto = pr;
 537                 r->e6.ipv6.flags |= IP6T_F_PROTO;
 538
 539                 if (proto->invert)
 540                         r->e6.ipv6.invflags |= XT_INV_PROTO;
 541         }
 542         else
 543 #endif
 544         {
 545                 r->e.ip.proto = pr;
 546
 547                 if (proto->invert)
 548                         r->e.ip.invflags |= XT_INV_PROTO;
 549         }
 550
 551         r->protocol = pr;
 552 }
 553
 554 void
 555 fw3_ipt_rule_in_out(struct fw3_ipt_rule *r,
 556                     struct fw3_device *in, struct fw3_device *out)
 557 {
 558 #ifndef DISABLE_IPV6
 559         if (r->h->family == FW3_FAMILY_V6)
 560         {
 561                 if (in && !in->any)
 562                 {
 563                         xtables_parse_interface(in->name, r->e6.ipv6.iniface,
 564                                                           r->e6.ipv6.iniface_mask);
 565
 566                         if (in->invert)
 567                                 r->e6.ipv6.invflags |= IP6T_INV_VIA_IN;
 568                 }
 569
 570                 if (out && !out->any)
 571                 {
 572                         xtables_parse_interface(out->name, r->e6.ipv6.outiface,
 573                                                            r->e6.ipv6.outiface_mask);
 574
 575                         if (out->invert)
 576                                 r->e6.ipv6.invflags |= IP6T_INV_VIA_OUT;
 577                 }
 578         }
 579         else
 580 #endif
 581         {
 582                 if (in && !in->any)
 583                 {
 584                         xtables_parse_interface(in->name, r->e.ip.iniface,
 585                                                           r->e.ip.iniface_mask);
 586
 587                         if (in->invert)
 588                                 r->e.ip.invflags |= IPT_INV_VIA_IN;
 589                 }
 590
 591                 if (out && !out->any)
 592                 {
 593                         xtables_parse_interface(out->name, r->e.ip.outiface,
 594                                                            r->e.ip.outiface_mask);
 595
 596                         if (out->invert)
 597                                 r->e.ip.invflags |= IPT_INV_VIA_OUT;
 598                 }
 599         }
 600 }
 601
 602
 603 static void
 604 ip4prefix2mask(int prefix, struct in_addr *mask)
 605 {
 606         mask->s_addr = htonl(~((1 << (32 - prefix)) - 1));
 607 }
 608
 609 #ifndef DISABLE_IPV6
 610 static void
 611 ip6prefix2mask(int prefix, struct in6_addr *mask)
 612 {
 613         char *p = (char *)mask;
 614
 615         if (prefix > 0)
 616         {
 617                 memset(p, 0xff, prefix / 8);
 618                 memset(p + (prefix / 8) + 1, 0, (128 - prefix) / 8);
 619                 p[prefix / 8] = 0xff << (8 - (prefix & 7));
 620         }
 621         else
 622         {
 623                 memset(mask, 0, sizeof(*mask));
 624         }
 625 }
 626 #endif
 627
 628 void
 629 fw3_ipt_rule_src_dest(struct fw3_ipt_rule *r,
 630                       struct fw3_address *src, struct fw3_address *dest)
 631 {
 632         if ((src && src->range) || (dest && dest->range))
 633         {
 634                 fw3_ipt_rule_addarg(r, false, "-m", "iprange");
 635         }
 636
 637         if (src && src->set)
 638         {
 639                 if (src->range)
 640                 {
 641                         fw3_ipt_rule_addarg(r, src->invert, "--src-range",
 642                                             fw3_address_to_string(src, false));
 643                 }
 644 #ifndef DISABLE_IPV6
 645                 else if (r->h->family == FW3_FAMILY_V6)
 646                 {
 647                         r->e6.ipv6.src = src->address.v6;
 648                         ip6prefix2mask(src->mask, &r->e6.ipv6.smsk);
 649
 650                         int i;
 651                         for (i = 0; i < 4; i++)
 652                                 r->e6.ipv6.src.s6_addr32[i] &= r->e6.ipv6.smsk.s6_addr32[i];
 653
 654                         if (src->invert)
 655                                 r->e6.ipv6.invflags |= IP6T_INV_SRCIP;
 656                 }
 657 #endif
 658                 else
 659                 {
 660                         r->e.ip.src = src->address.v4;
 661                         ip4prefix2mask(src->mask, &r->e.ip.smsk);
 662
 663                         r->e.ip.src.s_addr &= r->e.ip.smsk.s_addr;
 664
 665                         if (src->invert)
 666                                 r->e.ip.invflags |= IPT_INV_SRCIP;
 667                 }
 668         }
 669
 670         if (dest && dest->set)
 671         {
 672                 if (dest->range)
 673                 {
 674                         fw3_ipt_rule_addarg(r, dest->invert, "--dst-range",
 675                                             fw3_address_to_string(dest, false));
 676                 }
 677 #ifndef DISABLE_IPV6
 678                 else if (r->h->family == FW3_FAMILY_V6)
 679                 {
 680                         r->e6.ipv6.dst = dest->address.v6;
 681                         ip6prefix2mask(dest->mask, &r->e6.ipv6.dmsk);
 682
 683                         int i;
 684                         for (i = 0; i < 4; i++)
 685                                 r->e6.ipv6.dst.s6_addr32[i] &= r->e6.ipv6.dmsk.s6_addr32[i];
 686
 687                         if (dest->invert)
 688                                 r->e6.ipv6.invflags |= IP6T_INV_DSTIP;
 689                 }
 690 #endif
 691                 else
 692                 {
 693                         r->e.ip.dst = dest->address.v4;
 694                         ip4prefix2mask(dest->mask, &r->e.ip.dmsk);
 695
 696                         r->e.ip.dst.s_addr &= r->e.ip.dmsk.s_addr;
 697
 698                         if (dest->invert)
 699                                 r->e.ip.invflags |= IPT_INV_DSTIP;
 700                 }
 701         }
 702 }
 703
 704 void
 705 fw3_ipt_rule_sport_dport(struct fw3_ipt_rule *r,
 706                          struct fw3_port *sp, struct fw3_port *dp)
 707 {
 708         char buf[sizeof("65535:65535\0")];
 709
 710         if ((!sp || !sp->set) && (!dp || !dp->set))
 711                 return;
 712
 713         if (!get_protoname(r))
 714                 return;
 715
 716         if (sp && sp->set)
 717         {
 718                 if (sp->port_min == sp->port_max)
 719                         sprintf(buf, "%u", sp->port_min);
 720                 else
 721                         sprintf(buf, "%u:%u", sp->port_min, sp->port_max);
 722
 723                 fw3_ipt_rule_addarg(r, sp->invert, "--sport", buf);
 724         }
 725
 726         if (dp && dp->set)
 727         {
 728                 if (dp->port_min == dp->port_max)
 729                         sprintf(buf, "%u", dp->port_min);
 730                 else
 731                         sprintf(buf, "%u:%u", dp->port_min, dp->port_max);
 732
 733                 fw3_ipt_rule_addarg(r, dp->invert, "--dport", buf);
 734         }
 735 }
 736
 737 void
 738 fw3_ipt_rule_mac(struct fw3_ipt_rule *r, struct fw3_mac *mac)
 739 {
 740         if (!mac)
 741                 return;
 742
 743         fw3_ipt_rule_addarg(r, false, "-m", "mac");
 744         fw3_ipt_rule_addarg(r, mac->invert, "--mac-source", ether_ntoa(&mac->mac));
 745 }
 746
 747 void
 748 fw3_ipt_rule_icmptype(struct fw3_ipt_rule *r, struct fw3_icmptype *icmp)
 749 {
 750         char buf[sizeof("255/255\0")];
 751
 752         if (!icmp)
 753                 return;
 754
 755 #ifndef DISABLE_IPV6
 756         if (r->h->family == FW3_FAMILY_V6)
 757         {
 758                 if (icmp->code6_min == 0 && icmp->code6_max == 0xFF)
 759                         sprintf(buf, "%u", icmp->type6);
 760                 else
 761                         sprintf(buf, "%u/%u", icmp->type6, icmp->code6_min);
 762
 763                 fw3_ipt_rule_addarg(r, icmp->invert, "--icmpv6-type", buf);
 764         }
 765         else
 766 #endif
 767         {
 768                 if (icmp->code_min == 0 && icmp->code_max == 0xFF)
 769                         sprintf(buf, "%u", icmp->type);
 770                 else
 771                         sprintf(buf, "%u/%u", icmp->type, icmp->code_min);
 772
 773                 fw3_ipt_rule_addarg(r, icmp->invert, "--icmp-type", buf);
 774         }
 775 }
 776
 777 void
 778 fw3_ipt_rule_limit(struct fw3_ipt_rule *r, struct fw3_limit *limit)
 779 {
 780         char buf[sizeof("-4294967296/second\0")];
 781
 782         if (!limit || limit->rate <= 0)
 783                 return;
 784
 785         fw3_ipt_rule_addarg(r, false, "-m", "limit");
 786
 787         sprintf(buf, "%u/%s", limit->rate, fw3_limit_units[limit->unit]);
 788         fw3_ipt_rule_addarg(r, limit->invert, "--limit", buf);
 789
 790         if (limit->burst > 0)
 791         {
 792                 sprintf(buf, "%u", limit->burst);
 793                 fw3_ipt_rule_addarg(r, limit->invert, "--limit-burst", buf);
 794         }
 795 }
 796
 797 void
 798 fw3_ipt_rule_ipset(struct fw3_ipt_rule *r, struct fw3_ipset *ipset,
 799                    bool invert)
 800 {
 801         char buf[sizeof("dst,dst,dst\0")];
 802         char *p = buf;
 803
 804         struct fw3_ipset_datatype *type;
 805
 806         if (!ipset)
 807                 return;
 808
 809         list_for_each_entry(type, &ipset->datatypes, list)
 810         {
 811                 if (p > buf)
 812                         *p++ = ',';
 813
 814                 p += sprintf(p, "%s", type->dest ? "dst" : "src");
 815         }
 816
 817         fw3_ipt_rule_addarg(r, false, "-m", "set");
 818
 819         fw3_ipt_rule_addarg(r, invert, "--match-set",
 820                             ipset->external ? ipset->external : ipset->name);
 821
 822         fw3_ipt_rule_addarg(r, false, buf, NULL);
 823 }
 824
 825 void
 826 fw3_ipt_rule_time(struct fw3_ipt_rule *r, struct fw3_time *time)
 827 {
 828         int i;
 829         struct tm empty = { 0 };
 830
 831         char buf[84]; /* sizeof("1,2,3,...,30,31\0") */
 832         char *p;
 833
 834         bool d1 = memcmp(&time->datestart, &empty, sizeof(empty));
 835         bool d2 = memcmp(&time->datestop, &empty, sizeof(empty));
 836
 837         if (!d1 && !d2 && !time->timestart && !time->timestop &&
 838             !(time->monthdays & 0xFFFFFFFE) && !(time->weekdays & 0xFE))
 839         {
 840                 return;
 841         }
 842
 843         fw3_ipt_rule_addarg(r, false, "-m", "time");
 844
 845         if (time->utc)
 846                 fw3_ipt_rule_addarg(r, false, "--utc", NULL);
 847
 848         if (d1)
 849         {
 850                 strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%S", &time->datestart);
 851                 fw3_ipt_rule_addarg(r, false, "--datestart", buf);
 852         }
 853
 854         if (d2)
 855         {
 856                 strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%S", &time->datestop);
 857                 fw3_ipt_rule_addarg(r, false, "--datestop", buf);
 858         }
 859
 860         if (time->timestart)
 861         {
 862                 sprintf(buf, "%02d:%02d:%02d",
 863                         time->timestart / 3600,
 864                         time->timestart % 3600 / 60,
 865                         time->timestart % 60);
 866
 867                 fw3_ipt_rule_addarg(r, false, "--timestart", buf);
 868         }
 869
 870         if (time->timestop)
 871         {
 872                 sprintf(buf, "%02d:%02d:%02d",
 873                         time->timestop / 3600,
 874                         time->timestop % 3600 / 60,
 875                         time->timestop % 60);
 876
 877                 fw3_ipt_rule_addarg(r, false, "--timestop", buf);
 878         }
 879
 880         if (time->monthdays & 0xFFFFFFFE)
 881         {
 882                 for (i = 1, p = buf; i < 32; i++)
 883                 {
 884                         if (hasbit(time->monthdays, i))
 885                         {
 886                                 if (p > buf)
 887                                         *p++ = ',';
 888
 889                                 p += sprintf(p, "%u", i);
 890                         }
 891                 }
 892
 893                 fw3_ipt_rule_addarg(r, hasbit(time->monthdays, 0), "--monthdays", buf);
 894         }
 895
 896         if (time->weekdays & 0xFE)
 897         {
 898                 for (i = 1, p = buf; i < 8; i++)
 899                 {
 900                         if (hasbit(time->weekdays, i))
 901                         {
 902                                 if (p > buf)
 903                                         *p++ = ',';
 904
 905                                 p += sprintf(p, "%u", i);
 906                         }
 907                 }
 908
 909                 fw3_ipt_rule_addarg(r, hasbit(time->weekdays, 0), "--weekdays", buf);
 910         }
 911 }
 912
 913 void
 914 fw3_ipt_rule_mark(struct fw3_ipt_rule *r, struct fw3_mark *mark)
 915 {
 916         char buf[sizeof("0xFFFFFFFF/0xFFFFFFFF\0")];
 917
 918         if (!mark || !mark->set)
 919                 return;
 920
 921         if (mark->mask < 0xFFFFFFFF)
 922                 sprintf(buf, "0x%x/0x%x", mark->mark, mark->mask);
 923         else
 924                 sprintf(buf, "0x%x", mark->mark);
 925
 926         fw3_ipt_rule_addarg(r, false, "-m", "mark");
 927         fw3_ipt_rule_addarg(r, mark->invert, "--mark", buf);
 928 }
 929
 930 void
 931 fw3_ipt_rule_comment(struct fw3_ipt_rule *r, const char *fmt, ...)
 932 {
 933         va_list ap;
 934         char buf[256];
 935
 936         if (!fmt || !*fmt)
 937                 return;
 938
 939         va_start(ap, fmt);
 940         vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
 941         va_end(ap);
 942
 943         fw3_ipt_rule_addarg(r, false, "-m", "comment");
 944         fw3_ipt_rule_addarg(r, false, "--comment", buf);
 945 }
 946
 947 void
 948 fw3_ipt_rule_extra(struct fw3_ipt_rule *r, const char *extra)
 949 {
 950         char *p, **tmp, *s;
 951
 952         if (!extra || !*extra)
 953                 return;
 954
 955         s = fw3_strdup(extra);
 956
 957         for (p = strtok(s, " \t"); p; p = strtok(NULL, " \t"))
 958         {
 959                 tmp = realloc(r->argv, (r->argc + 1) * sizeof(*r->argv));
 960
 961                 if (!tmp)
 962                         break;
 963
 964                 r->argv = tmp;
 965                 r->argv[r->argc++] = fw3_strdup(p);
 966         }
 967
 968         free(s);
 969 }
 970
 971 #ifndef DISABLE_IPV6
 972 static void
 973 rule_print6(struct ip6t_entry *e)
 974 {
 975         char buf[INET6_ADDRSTRLEN];
 976         char *pname;
 977
 978         if (e->ipv6.flags & IP6T_F_PROTO)
 979         {
 980                 if (e->ipv6.flags & XT_INV_PROTO)
 981                         printf(" !");
 982
 983                 pname = get_protoname(container_of(e, struct fw3_ipt_rule, e6));
 984
 985                 if (pname)
 986                         printf(" -p %s", pname);
 987                 else
 988                         printf(" -p %u", e->ipv6.proto);
 989         }
 990
 991         if (e->ipv6.iniface[0])
 992         {
 993                 if (e->ipv6.flags & IP6T_INV_VIA_IN)
 994                         printf(" !");
 995
 996                 printf(" -i %s", e->ipv6.iniface);
 997         }
 998
 999         if (e->ipv6.outiface[0])
1000         {
1001                 if (e->ipv6.flags & IP6T_INV_VIA_OUT)
1002                         printf(" !");
1003
1004                 printf(" -o %s", e->ipv6.outiface);
1005         }
1006
1007         if (memcmp(&e->ipv6.src, &in6addr_any, sizeof(struct in6_addr)))
1008         {
1009                 if (e->ipv6.flags & IP6T_INV_SRCIP)
1010                         printf(" !");
1011
1012                 printf(" -s %s/%u", inet_ntop(AF_INET6, &e->ipv6.src, buf, sizeof(buf)),
1013                                     xtables_ip6mask_to_cidr(&e->ipv6.smsk));
1014         }
1015
1016         if (memcmp(&e->ipv6.dst, &in6addr_any, sizeof(struct in6_addr)))
1017         {
1018                 if (e->ipv6.flags & IP6T_INV_DSTIP)
1019                         printf(" !");
1020
1021                 printf(" -d %s/%u", inet_ntop(AF_INET6, &e->ipv6.dst, buf, sizeof(buf)),
1022                                     xtables_ip6mask_to_cidr(&e->ipv6.dmsk));
1023         }
1024 }
1025 #endif
1026
1027 static void
1028 rule_print4(struct ipt_entry *e)
1029 {
1030         struct in_addr in_zero = { 0 };
1031         char buf[sizeof("255.255.255.255\0")];
1032         char *pname;
1033
1034         if (e->ip.proto)
1035         {
1036                 if (e->ip.flags & XT_INV_PROTO)
1037                         printf(" !");
1038
1039                 pname = get_protoname(container_of(e, struct fw3_ipt_rule, e));
1040
1041                 if (pname)
1042                         printf(" -p %s", pname);
1043                 else
1044                         printf(" -p %u", e->ip.proto);
1045         }
1046
1047         if (e->ip.iniface[0])
1048         {
1049                 if (e->ip.flags & IPT_INV_VIA_IN)
1050                         printf(" !");
1051
1052                 printf(" -i %s", e->ip.iniface);
1053         }
1054
1055         if (e->ip.outiface[0])
1056         {
1057                 if (e->ip.flags & IPT_INV_VIA_OUT)
1058                         printf(" !");
1059
1060                 printf(" -o %s", e->ip.outiface);
1061         }
1062
1063         if (memcmp(&e->ip.src, &in_zero, sizeof(struct in_addr)))
1064         {
1065                 if (e->ip.flags & IPT_INV_SRCIP)
1066                         printf(" !");
1067
1068                 printf(" -s %s/%u", inet_ntop(AF_INET, &e->ip.src, buf, sizeof(buf)),
1069                                     xtables_ipmask_to_cidr(&e->ip.smsk));
1070         }
1071
1072         if (memcmp(&e->ip.dst, &in_zero, sizeof(struct in_addr)))
1073         {
1074                 if (e->ip.flags & IPT_INV_DSTIP)
1075                         printf(" !");
1076
1077                 printf(" -d %s/%u", inet_ntop(AF_INET, &e->ip.dst, buf, sizeof(buf)),
1078                                     xtables_ipmask_to_cidr(&e->ip.dmsk));
1079         }
1080 }
1081
1082 static void
1083 rule_print(struct fw3_ipt_rule *r, const char *chain)
1084 {
1085         struct xtables_rule_match *rm;
1086         struct xtables_match *m;
1087         struct xtables_target *t;
1088
1089         debug(r->h, "-A %s", chain);
1090
1091 #ifndef DISABLE_IPV6
1092         if (r->h->family == FW3_FAMILY_V6)
1093                 rule_print6(&r->e6);
1094         else
1095 #endif
1096                 rule_print4(&r->e);
1097
1098         for (rm = r->matches; rm; rm = rm->next)
1099         {
1100                 m = rm->match;
1101                 printf(" -m %s", fw3_xt_get_match_name(m));
1102
1103                 if (m->save)
1104                         m->save(&r->e.ip, m->m);
1105         }
1106
1107         if (r->target)
1108         {
1109                 t = r->target;
1110                 printf(" -j %s", fw3_xt_get_target_name(t));
1111
1112                 if (t->save)
1113                         t->save(&r->e.ip, t->t);
1114         }
1115
1116         printf("\n");
1117 }
1118
1119 static bool
1120 parse_option(struct fw3_ipt_rule *r, int optc, bool inv)
1121 {
1122         struct xtables_rule_match *m;
1123         struct xtables_match *em;
1124
1125         /* is a target option */
1126         if (r->target && fw3_xt_has_target_parse(r->target) &&
1127                 optc >= r->target->option_offset &&
1128                 optc < (r->target->option_offset + 256))
1129         {
1130                 xtables_option_tpcall(optc, r->argv, inv, r->target, &r->e);
1131                 return false;
1132         }
1133
1134         /* try to dispatch argument to one of the match parsers */
1135         for (m = r->matches; m; m = m->next)
1136         {
1137                 em = m->match;
1138
1139                 if (m->completed || !fw3_xt_has_match_parse(em))
1140                         continue;
1141
1142                 if (optc < em->option_offset ||
1143                         optc >= (em->option_offset + 256))
1144                         continue;
1145
1146                 xtables_option_mpcall(optc, r->argv, inv, em, &r->e);
1147                 return false;
1148         }
1149
1150         /* unhandled option, might belong to a protocol match */
1151         if ((em = load_protomatch(r)) != NULL)
1152         {
1153                 init_match(r, em, false);
1154
1155                 r->protocol_loaded = true;
1156                 optind--;
1157
1158                 return true;
1159         }
1160
1161         if (optc == ':')
1162                 fprintf(stderr, "parse_option(): option '%s' needs argument\n",
1163                         r->argv[optind-1]);
1164
1165         if (optc == '?')
1166                 fprintf(stderr, "parse_option(): unknown option '%s'\n",
1167                         r->argv[optind-1]);
1168
1169         return false;
1170 }
1171
1172 void
1173 fw3_ipt_rule_addarg(struct fw3_ipt_rule *r, bool inv,
1174                     const char *k, const char *v)
1175 {
1176         int n;
1177         char **tmp;
1178
1179         if (!k)
1180                 return;
1181
1182         n = inv + !!k + !!v;
1183         tmp = realloc(r->argv, (r->argc + n) * sizeof(*tmp));
1184
1185         if (!tmp)
1186                 return;
1187
1188         r->argv = tmp;
1189
1190         if (inv)
1191                 r->argv[r->argc++] = fw3_strdup("!");
1192
1193         r->argv[r->argc++] = fw3_strdup(k);
1194
1195         if (v)
1196                 r->argv[r->argc++] = fw3_strdup(v);
1197 }
1198
1199 void
1200 fw3_ipt_rule_append(struct fw3_ipt_rule *r, const char *fmt, ...)
1201 {
1202         size_t s;
1203         struct xtables_rule_match *m;
1204         struct xtables_match *em;
1205         struct xtables_target *et;
1206         struct xtables_globals *g;
1207         struct ipt_entry *e;
1208
1209         int i, optc;
1210         bool inv = false;
1211         char buf[32];
1212         va_list ap;
1213
1214         va_start(ap, fmt);
1215         vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
1216         va_end(ap);
1217
1218         g = (r->h->family == FW3_FAMILY_V6) ? &xtg6 : &xtg;
1219         g->opts = g->orig_opts;
1220
1221         optind = 0;
1222         opterr = 0;
1223
1224         while ((optc = getopt_long(r->argc, r->argv, "m:j:", g->opts, NULL)) != -1)
1225         {
1226                 switch (optc)
1227                 {
1228                 case 'm':
1229                         em = find_match(r, optarg);
1230
1231                         if (!em)
1232                         {
1233                                 fprintf(stderr, "fw3_ipt_rule_append(): Can't find match '%s'\n", optarg);
1234                                 goto free;
1235                         }
1236
1237                         init_match(r, em, true);
1238                         break;
1239
1240                 case 'j':
1241                         et = get_target(r, optarg);
1242
1243                         if (!et)
1244                         {
1245                                 fprintf(stderr, "fw3_ipt_rule_append(): Can't find target '%s'\n", optarg);
1246                                 goto free;
1247                         }
1248
1249                         break;
1250
1251                 case 1:
1252                         if ((optarg[0] == '!') && (optarg[1] == '\0'))
1253                         {
1254                                 inv = true;
1255                                 continue;
1256                         }
1257
1258                         fprintf(stderr, "fw3_ipt_rule_append(): Bad argument '%s'\n", optarg);
1259                         return;
1260
1261                 default:
1262                         if (parse_option(r, optc, inv))
1263                                 continue;
1264                         break;
1265                 }
1266
1267                 inv = false;
1268         }
1269
1270         for (m = r->matches; m; m = m->next)
1271                 xtables_option_mfcall(m->match);
1272
1273         if (r->target)
1274                 xtables_option_tfcall(r->target);
1275
1276         if (fw3_pr_debug)
1277                 rule_print(r, buf);
1278
1279 #ifndef DISABLE_IPV6
1280         if (r->h->family == FW3_FAMILY_V6)
1281         {
1282                 struct ip6t_entry *e6;
1283
1284                 s = XT_ALIGN(sizeof(struct ip6t_entry));
1285
1286                 for (m = r->matches; m; m = m->next)
1287                         s += m->match->m->u.match_size;
1288
1289                 e6 = fw3_alloc(s + r->target->t->u.target_size);
1290
1291                 memcpy(e6, &r->e6, sizeof(struct ip6t_entry));
1292
1293                 e6->target_offset = s;
1294                 e6->next_offset = s + r->target->t->u.target_size;
1295
1296                 s = 0;
1297
1298                 for (m = r->matches; m; m = m->next)
1299                 {
1300                         memcpy(e6->elems + s, m->match->m, m->match->m->u.match_size);
1301                         s += m->match->m->u.match_size;
1302                 }
1303
1304                 memcpy(e6->elems + s, r->target->t, r->target->t->u.target_size);
1305                 ip6tc_append_entry(buf, e6, r->h->handle);
1306                 free(e6);
1307         }
1308         else
1309 #endif
1310         {
1311                 s = XT_ALIGN(sizeof(struct ipt_entry));
1312
1313                 for (m = r->matches; m; m = m->next)
1314                         s += m->match->m->u.match_size;
1315
1316                 e = fw3_alloc(s + r->target->t->u.target_size);
1317
1318                 memcpy(e, &r->e, sizeof(struct ipt_entry));
1319
1320                 e->target_offset = s;
1321                 e->next_offset = s + r->target->t->u.target_size;
1322
1323                 s = 0;
1324
1325                 for (m = r->matches; m; m = m->next)
1326                 {
1327                         memcpy(e->elems + s, m->match->m, m->match->m->u.match_size);
1328                         s += m->match->m->u.match_size;
1329                 }
1330
1331                 memcpy(e->elems + s, r->target->t, r->target->t->u.target_size);
1332
1333                 if (!iptc_append_entry(buf, e, r->h->handle))
1334                         fprintf(stderr, "iptc_append_entry(): %s\n", iptc_strerror(errno));
1335
1336                 free(e);
1337         }
1338
1339 free:
1340         for (i = 1; i < r->argc; i++)
1341                 free(r->argv[i]);
1342
1343         free(r->argv);
1344
1345         xtables_rule_matches_free(&r->matches);
1346
1347         if (r->target)
1348                 free(r->target->t);
1349
1350         free(r);
1351
1352         /* reset all targets and matches */
1353         for (em = xtables_matches; em; em = em->next)
1354                 em->mflags = 0;
1355
1356         for (et = xtables_targets; et; et = et->next)
1357         {
1358                 et->tflags = 0;
1359                 et->used = 0;
1360         }
1361
1362         xtables_free_opts(1);
1363 }
1364
1365 struct fw3_ipt_rule *
1366 fw3_ipt_rule_create(struct fw3_ipt_handle *handle, struct fw3_protocol *proto,
1367                     struct fw3_device *in, struct fw3_device *out,
1368                     struct fw3_address *src, struct fw3_address *dest)
1369 {
1370         struct fw3_ipt_rule *r;
1371
1372         r = fw3_ipt_rule_new(handle);
1373
1374         fw3_ipt_rule_proto(r, proto);
1375         fw3_ipt_rule_in_out(r, in, out);
1376         fw3_ipt_rule_src_dest(r, src, dest);
1377
1378         return r;
1379 }