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         { NULL }
  26 };
  27
  28 static struct xtables_globals xtg = {
  29         .option_offset = 0,
  30         .program_version = "4",
  31         .orig_opts = base_opts,
  32 };
  33
  34 static struct xtables_globals xtg6 = {
  35         .option_offset = 0,
  36         .program_version = "6",
  37         .orig_opts = base_opts,
  38 };
  39
  40 /* Required by certain extensions like SNAT and DNAT */
  41 int kernel_version = 0;
  42
  43 void
  44 get_kernel_version(void)
  45 {
  46         static struct utsname uts;
  47         int x = 0, y = 0, z = 0;
  48
  49         if (uname(&uts) == -1)
  50                 sprintf(uts.release, "3.0.0");
  51
  52         sscanf(uts.release, "%d.%d.%d", &x, &y, &z);
  53         kernel_version = 0x10000 * x + 0x100 * y + z;
  54 }
  55
  56 static void fw3_init_extensions(void)
  57 {
  58         init_extensions();
  59         init_extensions4();
  60
  61 #ifndef DISABLE_IPV6
  62         init_extensions6();
  63 #endif
  64 }
  65
  66 struct fw3_ipt_handle *
  67 fw3_ipt_open(enum fw3_family family, enum fw3_table table)
  68 {
  69         struct fw3_ipt_handle *h;
  70
  71         h = fw3_alloc(sizeof(*h));
  72
  73         xtables_init();
  74
  75         if (family == FW3_FAMILY_V6)
  76         {
  77 #ifndef DISABLE_IPV6
  78                 h->family = FW3_FAMILY_V6;
  79                 h->table  = table;
  80                 h->handle = ip6tc_init(fw3_flag_names[table]);
  81
  82                 xtables_set_params(&xtg6);
  83                 xtables_set_nfproto(NFPROTO_IPV6);
  84 #endif
  85         }
  86         else
  87         {
  88                 h->family = FW3_FAMILY_V4;
  89                 h->table  = table;
  90                 h->handle = iptc_init(fw3_flag_names[table]);
  91
  92                 xtables_set_params(&xtg);
  93                 xtables_set_nfproto(NFPROTO_IPV4);
  94         }
  95
  96         if (!h->handle)
  97         {
  98                 free(h);
  99                 return NULL;
 100         }
 101
 102         fw3_xt_reset();
 103         fw3_init_extensions();
 104
 105         return h;
 106 }
 107
 108 static void
 109 debug(struct fw3_ipt_handle *h, const char *fmt, ...)
 110 {
 111         va_list ap;
 112
 113         printf("%s -t %s ", (h->family == FW3_FAMILY_V6) ? "ip6tables" : "iptables",
 114                             fw3_flag_names[h->table]);
 115
 116         va_start(ap, fmt);
 117         vprintf(fmt, ap);
 118         va_end(ap);
 119 }
 120
 121 void
 122 fw3_ipt_set_policy(struct fw3_ipt_handle *h, const char *chain,
 123                    enum fw3_flag policy)
 124 {
 125         if (fw3_pr_debug)
 126                 debug(h, "-P %s %s\n", chain, fw3_flag_names[policy]);
 127
 128 #ifndef DISABLE_IPV6
 129         if (h->family == FW3_FAMILY_V6)
 130                 ip6tc_set_policy(chain, fw3_flag_names[policy], NULL, h->handle);
 131         else
 132 #endif
 133                 iptc_set_policy(chain, fw3_flag_names[policy], NULL, h->handle);
 134 }
 135
 136 void
 137 fw3_ipt_flush_chain(struct fw3_ipt_handle *h, const char *chain)
 138 {
 139         if (fw3_pr_debug)
 140                 debug(h, "-F %s\n", chain);
 141
 142 #ifndef DISABLE_IPV6
 143         if (h->family == FW3_FAMILY_V6)
 144                 ip6tc_flush_entries(chain, h->handle);
 145         else
 146 #endif
 147                 iptc_flush_entries(chain, h->handle);
 148 }
 149
 150 static void
 151 delete_rules(struct fw3_ipt_handle *h, const char *target)
 152 {
 153         unsigned int num;
 154         const struct ipt_entry *e;
 155         const char *chain;
 156         const char *t;
 157         bool found;
 158
 159 #ifndef DISABLE_IPV6
 160         if (h->family == FW3_FAMILY_V6)
 161         {
 162                 for (chain = ip6tc_first_chain(h->handle);
 163                      chain != NULL;
 164                      chain = ip6tc_next_chain(h->handle))
 165                 {
 166                         do {
 167                                 found = false;
 168
 169                                 const struct ip6t_entry *e6;
 170                                 for (num = 0, e6 = ip6tc_first_rule(chain, h->handle);
 171                                          e6 != NULL;
 172                                          num++, e6 = ip6tc_next_rule(e6, h->handle))
 173                                 {
 174                                         t = ip6tc_get_target(e6, h->handle);
 175
 176                                         if (*t && !strcmp(t, target))
 177                                         {
 178                                                 if (fw3_pr_debug)
 179                                                         debug(h, "-D %s %u\n", chain, num + 1);
 180
 181                                                 ip6tc_delete_num_entry(chain, num, h->handle);
 182                                                 found = true;
 183                                                 break;
 184                                         }
 185                                 }
 186                         } while (found);
 187                 }
 188         }
 189         else
 190 #endif
 191         {
 192                 for (chain = iptc_first_chain(h->handle);
 193                      chain != NULL;
 194                      chain = iptc_next_chain(h->handle))
 195                 {
 196                         do {
 197                                 found = false;
 198
 199                                 for (num = 0, e = iptc_first_rule(chain, h->handle);
 200                                      e != NULL;
 201                                          num++, e = iptc_next_rule(e, h->handle))
 202                                 {
 203                                         t = iptc_get_target(e, h->handle);
 204
 205                                         if (*t && !strcmp(t, target))
 206                                         {
 207                                                 if (fw3_pr_debug)
 208                                                         debug(h, "-D %s %u\n", chain, num + 1);
 209
 210                                                 iptc_delete_num_entry(chain, num, h->handle);
 211                                                 found = true;
 212                                                 break;
 213                                         }
 214                                 }
 215                         } while (found);
 216                 }
 217         }
 218 }
 219
 220 void
 221 fw3_ipt_delete_chain(struct fw3_ipt_handle *h, const char *chain)
 222 {
 223         delete_rules(h, chain);
 224
 225         if (fw3_pr_debug)
 226                 debug(h, "-X %s\n", chain);
 227
 228 #ifndef DISABLE_IPV6
 229         if (h->family == FW3_FAMILY_V6)
 230                 ip6tc_delete_chain(chain, h->handle);
 231         else
 232 #endif
 233                 iptc_delete_chain(chain, h->handle);
 234 }
 235
 236 void
 237 fw3_ipt_create_chain(struct fw3_ipt_handle *h, const char *fmt, ...)
 238 {
 239         char buf[32];
 240         va_list ap;
 241
 242         va_start(ap, fmt);
 243         vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
 244         va_end(ap);
 245
 246         if (fw3_pr_debug)
 247                 debug(h, "-N %s\n", buf);
 248
 249         iptc_create_chain(buf, h->handle);
 250 }
 251
 252 void
 253 fw3_ipt_flush(struct fw3_ipt_handle *h)
 254 {
 255         const char *chain;
 256
 257 #ifndef DISABLE_IPV6
 258         if (h->family == FW3_FAMILY_V6)
 259         {
 260                 for (chain = ip6tc_first_chain(h->handle);
 261                      chain != NULL;
 262                      chain = ip6tc_next_chain(h->handle))
 263                 {
 264                         ip6tc_flush_entries(chain, h->handle);
 265                 }
 266
 267                 for (chain = ip6tc_first_chain(h->handle);
 268                      chain != NULL;
 269                      chain = ip6tc_next_chain(h->handle))
 270                 {
 271                         ip6tc_delete_chain(chain, h->handle);
 272                 }
 273         }
 274         else
 275 #endif
 276         {
 277                 for (chain = iptc_first_chain(h->handle);
 278                      chain != NULL;
 279                      chain = iptc_next_chain(h->handle))
 280                 {
 281                         iptc_flush_entries(chain, h->handle);
 282                 }
 283
 284                 for (chain = iptc_first_chain(h->handle);
 285                      chain != NULL;
 286                      chain = iptc_next_chain(h->handle))
 287                 {
 288                         iptc_delete_chain(chain, h->handle);
 289                 }
 290         }
 291 }
 292
 293 void
 294 fw3_ipt_commit(struct fw3_ipt_handle *h)
 295 {
 296         int rv;
 297
 298 #ifndef DISABLE_IPV6
 299         if (h->family == FW3_FAMILY_V6)
 300         {
 301                 rv = ip6tc_commit(h->handle);
 302                 if (!rv)
 303                         warn("ip6tc_commit(): %s", ip6tc_strerror(errno));
 304         }
 305         else
 306 #endif
 307         {
 308                 rv = iptc_commit(h->handle);
 309                 if (!rv)
 310                         warn("iptc_commit(): %s", iptc_strerror(errno));
 311         }
 312 }
 313
 314 void
 315 fw3_ipt_close(struct fw3_ipt_handle *h)
 316 {
 317         if (h->libv)
 318         {
 319                 while (h->libc > 0)
 320                 {
 321                         h->libc--;
 322                         dlclose(h->libv[h->libc]);
 323                 }
 324
 325                 free(h->libv);
 326         }
 327
 328         free(h);
 329 }
 330
 331 struct fw3_ipt_rule *
 332 fw3_ipt_rule_new(struct fw3_ipt_handle *h)
 333 {
 334         struct fw3_ipt_rule *r;
 335
 336         r = fw3_alloc(sizeof(*r));
 337
 338         r->h = h;
 339         r->argv = fw3_alloc(sizeof(char *));
 340         r->argv[r->argc++] = "fw3";
 341
 342         return r;
 343 }
 344
 345
 346 static bool
 347 is_chain(struct fw3_ipt_handle *h, const char *name)
 348 {
 349 #ifndef DISABLE_IPV6
 350         if (h->family == FW3_FAMILY_V6)
 351                 return ip6tc_is_chain(name, h->handle);
 352         else
 353 #endif
 354                 return iptc_is_chain(name, h->handle);
 355 }
 356
 357 static char *
 358 get_protoname(struct fw3_ipt_rule *r)
 359 {
 360         const struct xtables_pprot *pp;
 361
 362         if (r->protocol)
 363                 for (pp = xtables_chain_protos; pp->name; pp++)
 364                         if (pp->num == r->protocol)
 365                                 return (char *)pp->name;
 366
 367         return NULL;
 368 }
 369
 370 static bool
 371 load_extension(struct fw3_ipt_handle *h, const char *name)
 372 {
 373         char path[256];
 374         void *lib, **tmp;
 375         const char *pfx = (h->family == FW3_FAMILY_V6) ? "libip6t" : "libipt";
 376
 377         snprintf(path, sizeof(path), "/usr/lib/iptables/libxt_%s.so", name);
 378         if (!(lib = dlopen(path, RTLD_NOW)))
 379         {
 380                 snprintf(path, sizeof(path), "/usr/lib/iptables/%s_%s.so", pfx, name);
 381                 lib = dlopen(path, RTLD_NOW);
 382         }
 383
 384         if (!lib)
 385                 return false;
 386
 387         tmp = realloc(h->libv, sizeof(lib) * (h->libc + 1));
 388
 389         if (!tmp)
 390                 return false;
 391
 392         h->libv = tmp;
 393         h->libv[h->libc++] = lib;
 394
 395         return true;
 396 }
 397
 398 static struct xtables_match *
 399 find_match(struct fw3_ipt_rule *r, const char *name)
 400 {
 401         struct xtables_match *m;
 402
 403         m = xtables_find_match(name, XTF_DONT_LOAD, &r->matches);
 404
 405         if (!m && load_extension(r->h, name))
 406                 m = xtables_find_match(name, XTF_DONT_LOAD, &r->matches);
 407
 408         return m;
 409 }
 410
 411 static void
 412 init_match(struct fw3_ipt_rule *r, struct xtables_match *m, bool no_clone)
 413 {
 414         size_t s;
 415         struct xtables_globals *g;
 416
 417         if (!m)
 418                 return;
 419
 420         s = XT_ALIGN(sizeof(struct xt_entry_match)) + m->size;
 421
 422         m->m = fw3_alloc(s);
 423
 424         fw3_xt_set_match_name(m);
 425
 426         m->m->u.user.revision = m->revision;
 427         m->m->u.match_size = s;
 428
 429         /* free previous userspace data */
 430         fw3_xt_free_match_udata(m);
 431
 432         if (m->init)
 433                 m->init(m->m);
 434
 435         /* don't merge options if no_clone is set and this match is a clone */
 436         if (no_clone && (m == m->next))
 437                 return;
 438
 439         /* merge option table */
 440         g = (r->h->family == FW3_FAMILY_V6) ? &xtg6 : &xtg;
 441         fw3_xt_merge_match_options(g, m);
 442 }
 443
 444 static bool
 445 need_protomatch(struct fw3_ipt_rule *r, const char *pname)
 446 {
 447         if (!pname)
 448                 return false;
 449
 450         if (!xtables_find_match(pname, XTF_DONT_LOAD, NULL))
 451                 return true;
 452
 453         return !r->protocol_loaded;
 454 }
 455
 456 static struct xtables_match *
 457 load_protomatch(struct fw3_ipt_rule *r)
 458 {
 459         const char *pname = get_protoname(r);
 460
 461         if (!need_protomatch(r, pname))
 462                 return NULL;
 463
 464         return find_match(r, pname);
 465 }
 466
 467 static struct xtables_target *
 468 find_target(struct fw3_ipt_rule *r, const char *name)
 469 {
 470         struct xtables_target *t;
 471
 472         if (is_chain(r->h, name))
 473                 return xtables_find_target(XT_STANDARD_TARGET, XTF_LOAD_MUST_SUCCEED);
 474
 475         t = xtables_find_target(name, XTF_DONT_LOAD);
 476
 477         if (!t && load_extension(r->h, name))
 478                 t = xtables_find_target(name, XTF_DONT_LOAD);
 479
 480         return t;
 481 }
 482
 483 static struct xtables_target *
 484 get_target(struct fw3_ipt_rule *r, const char *name)
 485 {
 486         size_t s;
 487         struct xtables_target *t;
 488         struct xtables_globals *g;
 489
 490         t = find_target(r, name);
 491
 492         if (!t)
 493                 return NULL;
 494
 495         s = XT_ALIGN(sizeof(struct xt_entry_target)) + t->size;
 496         t->t = fw3_alloc(s);
 497
 498         fw3_xt_set_target_name(t, name);
 499
 500         t->t->u.user.revision = t->revision;
 501         t->t->u.target_size = s;
 502
 503         /* free previous userspace data */
 504         fw3_xt_free_target_udata(t);
 505
 506         if (t->init)
 507                 t->init(t->t);
 508
 509         /* merge option table */
 510         g = (r->h->family == FW3_FAMILY_V6) ? &xtg6 : &xtg;
 511         fw3_xt_merge_target_options(g, t);
 512
 513         r->target = t;
 514
 515         return t;
 516 }
 517
 518 void
 519 fw3_ipt_rule_proto(struct fw3_ipt_rule *r, struct fw3_protocol *proto)
 520 {
 521         uint32_t pr;
 522
 523         if (!proto || proto->any)
 524                 return;
 525
 526         pr = proto->protocol;
 527
 528 #ifndef DISABLE_IPV6
 529         if (r->h->family == FW3_FAMILY_V6)
 530         {
 531                 if (pr == 1)
 532                         pr = 58;
 533
 534                 r->e6.ipv6.proto = pr;
 535                 r->e6.ipv6.flags |= IP6T_F_PROTO;
 536
 537                 if (proto->invert)
 538                         r->e6.ipv6.invflags |= XT_INV_PROTO;
 539         }
 540         else
 541 #endif
 542         {
 543                 r->e.ip.proto = pr;
 544
 545                 if (proto->invert)
 546                         r->e.ip.invflags |= XT_INV_PROTO;
 547         }
 548
 549         r->protocol = pr;
 550 }
 551
 552 void
 553 fw3_ipt_rule_in_out(struct fw3_ipt_rule *r,
 554                     struct fw3_device *in, struct fw3_device *out)
 555 {
 556 #ifndef DISABLE_IPV6
 557         if (r->h->family == FW3_FAMILY_V6)
 558         {
 559                 if (in && !in->any)
 560                 {
 561                         xtables_parse_interface(in->name, r->e6.ipv6.iniface,
 562                                                           r->e6.ipv6.iniface_mask);
 563
 564                         if (in->invert)
 565                                 r->e6.ipv6.invflags |= IP6T_INV_VIA_IN;
 566                 }
 567
 568                 if (out && !out->any)
 569                 {
 570                         xtables_parse_interface(out->name, r->e6.ipv6.outiface,
 571                                                            r->e6.ipv6.outiface_mask);
 572
 573                         if (out->invert)
 574                                 r->e6.ipv6.invflags |= IP6T_INV_VIA_OUT;
 575                 }
 576         }
 577         else
 578 #endif
 579         {
 580                 if (in && !in->any)
 581                 {
 582                         xtables_parse_interface(in->name, r->e.ip.iniface,
 583                                                           r->e.ip.iniface_mask);
 584
 585                         if (in->invert)
 586                                 r->e.ip.invflags |= IPT_INV_VIA_IN;
 587                 }
 588
 589                 if (out && !out->any)
 590                 {
 591                         xtables_parse_interface(out->name, r->e.ip.outiface,
 592                                                            r->e.ip.outiface_mask);
 593
 594                         if (out->invert)
 595                                 r->e.ip.invflags |= IPT_INV_VIA_OUT;
 596                 }
 597         }
 598 }
 599
 600
 601 void
 602 fw3_ipt_rule_src_dest(struct fw3_ipt_rule *r,
 603                       struct fw3_address *src, struct fw3_address *dest)
 604 {
 605         if ((src && src->range) || (dest && dest->range))
 606         {
 607                 fw3_ipt_rule_addarg(r, false, "-m", "iprange");
 608         }
 609
 610         if (src && src->set)
 611         {
 612                 if (src->range)
 613                 {
 614                         fw3_ipt_rule_addarg(r, src->invert, "--src-range",
 615                                             fw3_address_to_string(src, false, false));
 616                 }
 617 #ifndef DISABLE_IPV6
 618                 else if (r->h->family == FW3_FAMILY_V6)
 619                 {
 620                         r->e6.ipv6.src = src->address.v6;
 621                         r->e6.ipv6.smsk = src->mask.v6;
 622
 623                         int i;
 624                         for (i = 0; i < 4; i++)
 625                                 r->e6.ipv6.src.s6_addr32[i] &= r->e6.ipv6.smsk.s6_addr32[i];
 626
 627                         if (src->invert)
 628                                 r->e6.ipv6.invflags |= IP6T_INV_SRCIP;
 629                 }
 630 #endif
 631                 else
 632                 {
 633                         r->e.ip.src = src->address.v4;
 634                         r->e.ip.smsk = src->mask.v4;
 635
 636                         r->e.ip.src.s_addr &= r->e.ip.smsk.s_addr;
 637
 638                         if (src->invert)
 639                                 r->e.ip.invflags |= IPT_INV_SRCIP;
 640                 }
 641         }
 642
 643         if (dest && dest->set)
 644         {
 645                 if (dest->range)
 646                 {
 647                         fw3_ipt_rule_addarg(r, dest->invert, "--dst-range",
 648                                             fw3_address_to_string(dest, false, false));
 649                 }
 650 #ifndef DISABLE_IPV6
 651                 else if (r->h->family == FW3_FAMILY_V6)
 652                 {
 653                         r->e6.ipv6.dst = dest->address.v6;
 654                         r->e6.ipv6.dmsk = dest->mask.v6;
 655
 656                         int i;
 657                         for (i = 0; i < 4; i++)
 658                                 r->e6.ipv6.dst.s6_addr32[i] &= r->e6.ipv6.dmsk.s6_addr32[i];
 659
 660                         if (dest->invert)
 661                                 r->e6.ipv6.invflags |= IP6T_INV_DSTIP;
 662                 }
 663 #endif
 664                 else
 665                 {
 666                         r->e.ip.dst = dest->address.v4;
 667                         r->e.ip.dmsk = dest->mask.v4;
 668
 669                         r->e.ip.dst.s_addr &= r->e.ip.dmsk.s_addr;
 670
 671                         if (dest->invert)
 672                                 r->e.ip.invflags |= IPT_INV_DSTIP;
 673                 }
 674         }
 675 }
 676
 677 void
 678 fw3_ipt_rule_sport_dport(struct fw3_ipt_rule *r,
 679                          struct fw3_port *sp, struct fw3_port *dp)
 680 {
 681         char buf[sizeof("65535:65535\0")];
 682
 683         if ((!sp || !sp->set) && (!dp || !dp->set))
 684                 return;
 685
 686         if (!get_protoname(r))
 687                 return;
 688
 689         if (sp && sp->set)
 690         {
 691                 if (sp->port_min == sp->port_max)
 692                         sprintf(buf, "%u", sp->port_min);
 693                 else
 694                         sprintf(buf, "%u:%u", sp->port_min, sp->port_max);
 695
 696                 fw3_ipt_rule_addarg(r, sp->invert, "--sport", buf);
 697         }
 698
 699         if (dp && dp->set)
 700         {
 701                 if (dp->port_min == dp->port_max)
 702                         sprintf(buf, "%u", dp->port_min);
 703                 else
 704                         sprintf(buf, "%u:%u", dp->port_min, dp->port_max);
 705
 706                 fw3_ipt_rule_addarg(r, dp->invert, "--dport", buf);
 707         }
 708 }
 709
 710 void
 711 fw3_ipt_rule_device(struct fw3_ipt_rule *r, const char *device, bool out)
 712 {
 713         if (device) {
 714                 struct fw3_device dev = { .any = false };
 715                 strncpy(dev.name, device, sizeof(dev.name) - 1);
 716                 fw3_ipt_rule_in_out(r, (out) ? NULL : &dev, (out) ? &dev : NULL);
 717         }
 718 }
 719
 720 void
 721 fw3_ipt_rule_mac(struct fw3_ipt_rule *r, struct fw3_mac *mac)
 722 {
 723         char buf[sizeof("ff:ff:ff:ff:ff:ff\0")];
 724         uint8_t *addr = mac->mac.ether_addr_octet;
 725
 726         if (!mac)
 727                 return;
 728
 729         sprintf(buf, "%02x:%02x:%02x:%02x:%02x:%02x",
 730                 addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]);
 731
 732         fw3_ipt_rule_addarg(r, false, "-m", "mac");
 733         fw3_ipt_rule_addarg(r, mac->invert, "--mac-source", buf);
 734 }
 735
 736 void
 737 fw3_ipt_rule_icmptype(struct fw3_ipt_rule *r, struct fw3_icmptype *icmp)
 738 {
 739         char buf[sizeof("255/255\0")];
 740
 741         if (!icmp)
 742                 return;
 743
 744 #ifndef DISABLE_IPV6
 745         if (r->h->family == FW3_FAMILY_V6)
 746         {
 747                 if (icmp->code6_min == 0 && icmp->code6_max == 0xFF)
 748                         sprintf(buf, "%u", icmp->type6);
 749                 else
 750                         sprintf(buf, "%u/%u", icmp->type6, icmp->code6_min);
 751
 752                 fw3_ipt_rule_addarg(r, icmp->invert, "--icmpv6-type", buf);
 753         }
 754         else
 755 #endif
 756         {
 757                 if (icmp->code_min == 0 && icmp->code_max == 0xFF)
 758                         sprintf(buf, "%u", icmp->type);
 759                 else
 760                         sprintf(buf, "%u/%u", icmp->type, icmp->code_min);
 761
 762                 fw3_ipt_rule_addarg(r, icmp->invert, "--icmp-type", buf);
 763         }
 764 }
 765
 766 void
 767 fw3_ipt_rule_limit(struct fw3_ipt_rule *r, struct fw3_limit *limit)
 768 {
 769         char buf[sizeof("-4294967296/second\0")];
 770
 771         if (!limit || limit->rate <= 0)
 772                 return;
 773
 774         fw3_ipt_rule_addarg(r, false, "-m", "limit");
 775
 776         sprintf(buf, "%u/%s", limit->rate, fw3_limit_units[limit->unit]);
 777         fw3_ipt_rule_addarg(r, limit->invert, "--limit", buf);
 778
 779         if (limit->burst > 0)
 780         {
 781                 sprintf(buf, "%u", limit->burst);
 782                 fw3_ipt_rule_addarg(r, limit->invert, "--limit-burst", buf);
 783         }
 784 }
 785
 786 void
 787 fw3_ipt_rule_ipset(struct fw3_ipt_rule *r, struct fw3_setmatch *match)
 788 {
 789         char buf[sizeof("dst,dst,dst\0")];
 790         char *p = buf;
 791         int i = 0;
 792
 793         struct fw3_ipset *set;
 794         struct fw3_ipset_datatype *type;
 795
 796         if (!match || !match->set || !match->ptr)
 797                 return;
 798
 799         set = match->ptr;
 800         list_for_each_entry(type, &set->datatypes, list)
 801         {
 802                 if (i >= 3)
 803                         break;
 804
 805                 if (p > buf)
 806                         *p++ = ',';
 807
 808                 p += sprintf(p, "%s", match->dir[i] ? match->dir[i] : type->dir);
 809                 i++;
 810         }
 811
 812         fw3_ipt_rule_addarg(r, false, "-m", "set");
 813
 814         fw3_ipt_rule_addarg(r, match->invert, "--match-set",
 815                             set->external ? set->external : set->name);
 816
 817         fw3_ipt_rule_addarg(r, false, buf, NULL);
 818 }
 819
 820 void
 821 fw3_ipt_rule_time(struct fw3_ipt_rule *r, struct fw3_time *time)
 822 {
 823         int i;
 824         struct tm empty = { 0 };
 825
 826         char buf[84]; /* sizeof("1,2,3,...,30,31\0") */
 827         char *p;
 828
 829         bool d1 = memcmp(&time->datestart, &empty, sizeof(empty));
 830         bool d2 = memcmp(&time->datestop, &empty, sizeof(empty));
 831
 832         if (!d1 && !d2 && !time->timestart && !time->timestop &&
 833             !(time->monthdays & 0xFFFFFFFE) && !(time->weekdays & 0xFE))
 834         {
 835                 return;
 836         }
 837
 838         fw3_ipt_rule_addarg(r, false, "-m", "time");
 839
 840         if (time->utc)
 841                 fw3_ipt_rule_addarg(r, false, "--utc", NULL);
 842
 843         if (d1)
 844         {
 845                 strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%S", &time->datestart);
 846                 fw3_ipt_rule_addarg(r, false, "--datestart", buf);
 847         }
 848
 849         if (d2)
 850         {
 851                 strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%S", &time->datestop);
 852                 fw3_ipt_rule_addarg(r, false, "--datestop", buf);
 853         }
 854
 855         if (time->timestart)
 856         {
 857                 sprintf(buf, "%02d:%02d:%02d",
 858                         time->timestart / 3600,
 859                         time->timestart % 3600 / 60,
 860                         time->timestart % 60);
 861
 862                 fw3_ipt_rule_addarg(r, false, "--timestart", buf);
 863         }
 864
 865         if (time->timestop)
 866         {
 867                 sprintf(buf, "%02d:%02d:%02d",
 868                         time->timestop / 3600,
 869                         time->timestop % 3600 / 60,
 870                         time->timestop % 60);
 871
 872                 fw3_ipt_rule_addarg(r, false, "--timestop", buf);
 873         }
 874
 875         if (time->monthdays & 0xFFFFFFFE)
 876         {
 877                 for (i = 1, p = buf; i < 32; i++)
 878                 {
 879                         if (hasbit(time->monthdays, i))
 880                         {
 881                                 if (p > buf)
 882                                         *p++ = ',';
 883
 884                                 p += sprintf(p, "%u", i);
 885                         }
 886                 }
 887
 888                 fw3_ipt_rule_addarg(r, hasbit(time->monthdays, 0), "--monthdays", buf);
 889         }
 890
 891         if (time->weekdays & 0xFE)
 892         {
 893                 for (i = 1, p = buf; i < 8; i++)
 894                 {
 895                         if (hasbit(time->weekdays, i))
 896                         {
 897                                 if (p > buf)
 898                                         *p++ = ',';
 899
 900                                 p += sprintf(p, "%u", i);
 901                         }
 902                 }
 903
 904                 fw3_ipt_rule_addarg(r, hasbit(time->weekdays, 0), "--weekdays", buf);
 905         }
 906 }
 907
 908 void
 909 fw3_ipt_rule_mark(struct fw3_ipt_rule *r, struct fw3_mark *mark)
 910 {
 911         char buf[sizeof("0xFFFFFFFF/0xFFFFFFFF\0")];
 912
 913         if (!mark || !mark->set)
 914                 return;
 915
 916         if (mark->mask < 0xFFFFFFFF)
 917                 sprintf(buf, "0x%x/0x%x", mark->mark, mark->mask);
 918         else
 919                 sprintf(buf, "0x%x", mark->mark);
 920
 921         fw3_ipt_rule_addarg(r, false, "-m", "mark");
 922         fw3_ipt_rule_addarg(r, mark->invert, "--mark", buf);
 923 }
 924
 925 void
 926 fw3_ipt_rule_comment(struct fw3_ipt_rule *r, const char *fmt, ...)
 927 {
 928         va_list ap;
 929         char buf[256];
 930
 931         if (!fmt || !*fmt)
 932                 return;
 933
 934         va_start(ap, fmt);
 935         vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
 936         va_end(ap);
 937
 938         fw3_ipt_rule_addarg(r, false, "-m", "comment");
 939         fw3_ipt_rule_addarg(r, false, "--comment", buf);
 940 }
 941
 942 void
 943 fw3_ipt_rule_extra(struct fw3_ipt_rule *r, const char *extra)
 944 {
 945         char *p, **tmp, *s;
 946
 947         if (!extra || !*extra)
 948                 return;
 949
 950         s = fw3_strdup(extra);
 951
 952         for (p = strtok(s, " \t"); p; p = strtok(NULL, " \t"))
 953         {
 954                 tmp = realloc(r->argv, (r->argc + 1) * sizeof(*r->argv));
 955
 956                 if (!tmp)
 957                         break;
 958
 959                 r->argv = tmp;
 960                 r->argv[r->argc++] = fw3_strdup(p);
 961         }
 962
 963         free(s);
 964 }
 965
 966 #ifndef DISABLE_IPV6
 967 static void
 968 rule_print6(struct ip6t_entry *e)
 969 {
 970         char buf1[INET6_ADDRSTRLEN], buf2[INET6_ADDRSTRLEN];
 971         char *pname;
 972
 973         if (e->ipv6.flags & IP6T_F_PROTO)
 974         {
 975                 if (e->ipv6.flags & XT_INV_PROTO)
 976                         printf(" !");
 977
 978                 pname = get_protoname(container_of(e, struct fw3_ipt_rule, e6));
 979
 980                 if (pname)
 981                         printf(" -p %s", pname);
 982                 else
 983                         printf(" -p %u", e->ipv6.proto);
 984         }
 985
 986         if (e->ipv6.iniface[0])
 987         {
 988                 if (e->ipv6.flags & IP6T_INV_VIA_IN)
 989                         printf(" !");
 990
 991                 printf(" -i %s", e->ipv6.iniface);
 992         }
 993
 994         if (e->ipv6.outiface[0])
 995         {
 996                 if (e->ipv6.flags & IP6T_INV_VIA_OUT)
 997                         printf(" !");
 998
 999                 printf(" -o %s", e->ipv6.outiface);
1000         }
1001
1002         if (memcmp(&e->ipv6.src, &in6addr_any, sizeof(struct in6_addr)))
1003         {
1004                 if (e->ipv6.flags & IP6T_INV_SRCIP)
1005                         printf(" !");
1006
1007                 printf(" -s %s/%s",
1008                        inet_ntop(AF_INET6, &e->ipv6.src, buf1, sizeof(buf1)),
1009                        inet_ntop(AF_INET6, &e->ipv6.smsk, buf2, sizeof(buf2)));
1010         }
1011
1012         if (memcmp(&e->ipv6.dst, &in6addr_any, sizeof(struct in6_addr)))
1013         {
1014                 if (e->ipv6.flags & IP6T_INV_DSTIP)
1015                         printf(" !");
1016
1017                 printf(" -d %s/%s",
1018                        inet_ntop(AF_INET6, &e->ipv6.dst, buf1, sizeof(buf1)),
1019                        inet_ntop(AF_INET6, &e->ipv6.dmsk, buf2, sizeof(buf2)));
1020         }
1021 }
1022 #endif
1023
1024 static void
1025 rule_print4(struct ipt_entry *e)
1026 {
1027         struct in_addr in_zero = { 0 };
1028         char buf1[sizeof("255.255.255.255\0")], buf2[sizeof("255.255.255.255\0")];
1029         char *pname;
1030
1031         if (e->ip.proto)
1032         {
1033                 if (e->ip.flags & XT_INV_PROTO)
1034                         printf(" !");
1035
1036                 pname = get_protoname(container_of(e, struct fw3_ipt_rule, e));
1037
1038                 if (pname)
1039                         printf(" -p %s", pname);
1040                 else
1041                         printf(" -p %u", e->ip.proto);
1042         }
1043
1044         if (e->ip.iniface[0])
1045         {
1046                 if (e->ip.flags & IPT_INV_VIA_IN)
1047                         printf(" !");
1048
1049                 printf(" -i %s", e->ip.iniface);
1050         }
1051
1052         if (e->ip.outiface[0])
1053         {
1054                 if (e->ip.flags & IPT_INV_VIA_OUT)
1055                         printf(" !");
1056
1057                 printf(" -o %s", e->ip.outiface);
1058         }
1059
1060         if (memcmp(&e->ip.src, &in_zero, sizeof(struct in_addr)))
1061         {
1062                 if (e->ip.flags & IPT_INV_SRCIP)
1063                         printf(" !");
1064
1065                 printf(" -s %s/%s",
1066                        inet_ntop(AF_INET, &e->ip.src, buf1, sizeof(buf1)),
1067                        inet_ntop(AF_INET, &e->ip.smsk, buf2, sizeof(buf2)));
1068         }
1069
1070         if (memcmp(&e->ip.dst, &in_zero, sizeof(struct in_addr)))
1071         {
1072                 if (e->ip.flags & IPT_INV_DSTIP)
1073                         printf(" !");
1074
1075                 printf(" -d %s/%s",
1076                        inet_ntop(AF_INET, &e->ip.dst, buf1, sizeof(buf1)),
1077                        inet_ntop(AF_INET, &e->ip.dmsk, buf2, sizeof(buf2)));
1078         }
1079 }
1080
1081 static void
1082 rule_print(struct fw3_ipt_rule *r, const char *prefix, const char *chain)
1083 {
1084         debug(r->h, "%s %s", prefix, chain);
1085
1086 #ifndef DISABLE_IPV6
1087         if (r->h->family == FW3_FAMILY_V6)
1088                 rule_print6(&r->e6);
1089         else
1090 #endif
1091                 rule_print4(&r->e);
1092
1093         fw3_xt_print_matches(&r->e.ip, r->matches);
1094         fw3_xt_print_target(&r->e.ip, r->target);
1095
1096         printf("\n");
1097 }
1098
1099 static bool
1100 parse_option(struct fw3_ipt_rule *r, int optc, bool inv)
1101 {
1102         struct xtables_rule_match *m;
1103         struct xtables_match *em;
1104
1105         /* is a target option */
1106         if (r->target && fw3_xt_has_target_parse(r->target) &&
1107                 optc >= r->target->option_offset &&
1108                 optc < (r->target->option_offset + 256))
1109         {
1110                 xtables_option_tpcall(optc, r->argv, inv, r->target, &r->e);
1111                 return false;
1112         }
1113
1114         /* try to dispatch argument to one of the match parsers */
1115         for (m = r->matches; m; m = m->next)
1116         {
1117                 em = m->match;
1118
1119                 if (m->completed || !fw3_xt_has_match_parse(em))
1120                         continue;
1121
1122                 if (optc < em->option_offset ||
1123                         optc >= (em->option_offset + 256))
1124                         continue;
1125
1126                 xtables_option_mpcall(optc, r->argv, inv, em, &r->e);
1127                 return false;
1128         }
1129
1130         /* unhandled option, might belong to a protocol match */
1131         if ((em = load_protomatch(r)) != NULL)
1132         {
1133                 init_match(r, em, false);
1134
1135                 r->protocol_loaded = true;
1136                 optind--;
1137
1138                 return true;
1139         }
1140
1141         if (optc == ':')
1142                 warn("parse_option(): option '%s' needs argument", r->argv[optind-1]);
1143
1144         if (optc == '?')
1145                 warn("parse_option(): unknown option '%s'", r->argv[optind-1]);
1146
1147         return false;
1148 }
1149
1150 void
1151 fw3_ipt_rule_addarg(struct fw3_ipt_rule *r, bool inv,
1152                     const char *k, const char *v)
1153 {
1154         int n;
1155         char **tmp;
1156
1157         if (!k)
1158                 return;
1159
1160         n = inv + !!k + !!v;
1161         tmp = realloc(r->argv, (r->argc + n) * sizeof(*tmp));
1162
1163         if (!tmp)
1164                 return;
1165
1166         r->argv = tmp;
1167
1168         if (inv)
1169                 r->argv[r->argc++] = fw3_strdup("!");
1170
1171         r->argv[r->argc++] = fw3_strdup(k);
1172
1173         if (v)
1174                 r->argv[r->argc++] = fw3_strdup(v);
1175 }
1176
1177 static unsigned char *
1178 rule_mask(struct fw3_ipt_rule *r)
1179 {
1180         size_t s;
1181         unsigned char *p, *mask = NULL;
1182         struct xtables_rule_match *m;
1183
1184 #define SZ(x) XT_ALIGN(sizeof(struct x))
1185
1186 #ifndef DISABLE_IPV6
1187         if (r->h->family == FW3_FAMILY_V6)
1188         {
1189                 s = SZ(ip6t_entry);
1190
1191                 for (m = r->matches; m; m = m->next)
1192                         s += SZ(ip6t_entry_match) + m->match->size;
1193
1194                 s += SZ(ip6t_entry_target);
1195                 if (r->target)
1196                         s += r->target->size;
1197
1198                 mask = fw3_alloc(s);
1199                 memset(mask, 0xFF, SZ(ip6t_entry));
1200                 p = mask + SZ(ip6t_entry);
1201
1202                 for (m = r->matches; m; m = m->next)
1203                 {
1204                         memset(p, 0xFF, SZ(ip6t_entry_match) + m->match->userspacesize);
1205                         p += SZ(ip6t_entry_match) + m->match->size;
1206                 }
1207
1208                 memset(p, 0xFF, SZ(ip6t_entry_target) + (r->target) ? r->target->userspacesize : 0);
1209         }
1210         else
1211 #endif
1212         {
1213                 s = SZ(ipt_entry);
1214
1215                 for (m = r->matches; m; m = m->next)
1216                         s += SZ(ipt_entry_match) + m->match->size;
1217
1218                 s += SZ(ipt_entry_target);
1219                 if (r->target)
1220                         s += r->target->size;
1221
1222                 mask = fw3_alloc(s);
1223                 memset(mask, 0xFF, SZ(ipt_entry));
1224                 p = mask + SZ(ipt_entry);
1225
1226                 for (m = r->matches; m; m = m->next)
1227                 {
1228                         memset(p, 0xFF, SZ(ipt_entry_match) + m->match->userspacesize);
1229                         p += SZ(ipt_entry_match) + m->match->size;
1230                 }
1231
1232                 memset(p, 0xFF, SZ(ipt_entry_target) + (r->target) ? r->target->userspacesize : 0);
1233         }
1234
1235         return mask;
1236 }
1237
1238 static void *
1239 rule_build(struct fw3_ipt_rule *r)
1240 {
1241         size_t s, target_size = (r->target) ? r->target->t->u.target_size : 0;
1242         struct xtables_rule_match *m;
1243
1244 #ifndef DISABLE_IPV6
1245         if (r->h->family == FW3_FAMILY_V6)
1246         {
1247                 struct ip6t_entry *e6;
1248
1249                 s = XT_ALIGN(sizeof(struct ip6t_entry));
1250
1251                 for (m = r->matches; m; m = m->next)
1252                         s += m->match->m->u.match_size;
1253
1254                 e6 = fw3_alloc(s + target_size);
1255
1256                 memcpy(e6, &r->e6, sizeof(struct ip6t_entry));
1257
1258                 e6->target_offset = s;
1259                 e6->next_offset = s + target_size;
1260
1261                 s = 0;
1262
1263                 for (m = r->matches; m; m = m->next)
1264                 {
1265                         memcpy(e6->elems + s, m->match->m, m->match->m->u.match_size);
1266                         s += m->match->m->u.match_size;
1267                 }
1268
1269                 if (target_size)
1270                         memcpy(e6->elems + s, r->target->t, target_size);
1271
1272                 return e6;
1273         }
1274         else
1275 #endif
1276         {
1277                 struct ipt_entry *e;
1278
1279                 s = XT_ALIGN(sizeof(struct ipt_entry));
1280
1281                 for (m = r->matches; m; m = m->next)
1282                         s += m->match->m->u.match_size;
1283
1284                 e = fw3_alloc(s + target_size);
1285
1286                 memcpy(e, &r->e, sizeof(struct ipt_entry));
1287
1288                 e->target_offset = s;
1289                 e->next_offset = s + target_size;
1290
1291                 s = 0;
1292
1293                 for (m = r->matches; m; m = m->next)
1294                 {
1295                         memcpy(e->elems + s, m->match->m, m->match->m->u.match_size);
1296                         s += m->match->m->u.match_size;
1297                 }
1298
1299                 if (target_size)
1300                         memcpy(e->elems + s, r->target->t, target_size);
1301
1302                 return e;
1303         }
1304 }
1305
1306 void
1307 __fw3_ipt_rule_append(struct fw3_ipt_rule *r, bool repl, const char *fmt, ...)
1308 {
1309         void *rule;
1310         unsigned char *mask;
1311
1312         struct xtables_rule_match *m;
1313         struct xtables_match *em;
1314         struct xtables_target *et;
1315         struct xtables_globals *g;
1316
1317         int i, optc;
1318         bool inv = false;
1319         char buf[32];
1320         va_list ap;
1321
1322         va_start(ap, fmt);
1323         vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
1324         va_end(ap);
1325
1326         g = (r->h->family == FW3_FAMILY_V6) ? &xtg6 : &xtg;
1327         g->opts = g->orig_opts;
1328
1329         optind = 0;
1330         opterr = 0;
1331
1332         while ((optc = getopt_long(r->argc, r->argv, "-:m:j:", g->opts,
1333                                    NULL)) != -1)
1334         {
1335                 switch (optc)
1336                 {
1337                 case 'm':
1338                         em = find_match(r, optarg);
1339
1340                         if (!em)
1341                         {
1342                                 warn("fw3_ipt_rule_append(): Can't find match '%s'", optarg);
1343                                 goto free;
1344                         }
1345
1346                         init_match(r, em, true);
1347                         break;
1348
1349                 case 'j':
1350                         et = get_target(r, optarg);
1351
1352                         if (!et)
1353                         {
1354                                 warn("fw3_ipt_rule_append(): Can't find target '%s'", optarg);
1355                                 goto free;
1356                         }
1357
1358                         break;
1359
1360                 case 1:
1361                         if ((optarg[0] == '!') && (optarg[1] == '\0'))
1362                         {
1363                                 optarg[0] = '\0';
1364                                 inv = true;
1365                                 continue;
1366                         }
1367
1368                         warn("fw3_ipt_rule_append(): Bad argument '%s'", optarg);
1369                         goto free;
1370
1371                 default:
1372                         if (parse_option(r, optc, inv))
1373                                 continue;
1374                         break;
1375                 }
1376
1377                 inv = false;
1378         }
1379
1380         for (m = r->matches; m; m = m->next)
1381                 xtables_option_mfcall(m->match);
1382
1383         if (r->target)
1384                 xtables_option_tfcall(r->target);
1385
1386         rule = rule_build(r);
1387
1388 #ifndef DISABLE_IPV6
1389         if (r->h->family == FW3_FAMILY_V6)
1390         {
1391                 if (repl)
1392                 {
1393                         mask = rule_mask(r);
1394
1395                         while (ip6tc_delete_entry(buf, rule, mask, r->h->handle))
1396                                 if (fw3_pr_debug)
1397                                         rule_print(r, "-D", buf);
1398
1399                         free(mask);
1400                 }
1401
1402                 if (fw3_pr_debug)
1403                         rule_print(r, "-A", buf);
1404
1405                 if (!ip6tc_append_entry(buf, rule, r->h->handle))
1406                         warn("ip6tc_append_entry(): %s", ip6tc_strerror(errno));
1407         }
1408         else
1409 #endif
1410         {
1411                 if (repl)
1412                 {
1413                         mask = rule_mask(r);
1414
1415                         while (iptc_delete_entry(buf, rule, mask, r->h->handle))
1416                                 if (fw3_pr_debug)
1417                                         rule_print(r, "-D", buf);
1418
1419                         free(mask);
1420                 }
1421
1422                 if (fw3_pr_debug)
1423                         rule_print(r, "-A", buf);
1424
1425                 if (!iptc_append_entry(buf, rule, r->h->handle))
1426                         warn("iptc_append_entry(): %s\n", iptc_strerror(errno));
1427         }
1428
1429         free(rule);
1430
1431 free:
1432         for (i = 1; i < r->argc; i++)
1433                 free(r->argv[i]);
1434
1435         free(r->argv);
1436
1437         xtables_rule_matches_free(&r->matches);
1438
1439         if (r->target)
1440                 free(r->target->t);
1441
1442         free(r);
1443
1444         /* reset all targets and matches */
1445         for (em = xtables_matches; em; em = em->next)
1446                 em->mflags = 0;
1447
1448         for (et = xtables_targets; et; et = et->next)
1449         {
1450                 et->tflags = 0;
1451                 et->used = 0;
1452         }
1453
1454         xtables_free_opts(1);
1455 }
1456
1457 struct fw3_ipt_rule *
1458 fw3_ipt_rule_create(struct fw3_ipt_handle *handle, struct fw3_protocol *proto,
1459                     struct fw3_device *in, struct fw3_device *out,
1460                     struct fw3_address *src, struct fw3_address *dest)
1461 {
1462         struct fw3_ipt_rule *r;
1463
1464         r = fw3_ipt_rule_new(handle);
1465
1466         fw3_ipt_rule_proto(r, proto);
1467         fw3_ipt_rule_in_out(r, in, out);
1468         fw3_ipt_rule_src_dest(r, src, dest);
1469
1470         return r;
1471 }