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 #ifdef DISABLE_IPV6
  57 #undef __ipt_module
  58 #define __ipt_module(x) libxt_##x##_init, libipt_##x##_init,
  59 #else
  60 #undef __ipt_module
  61 #define __ipt_module(x) libxt_##x##_init, libipt_##x##_init, libip6t_##x##_init,
  62 #endif
  63
  64 static void fw3_init_extensions(void)
  65 {
  66         int i;
  67         void (*initfuncs[])(void) = { FW3_IPT_MODULES };
  68
  69         for (i = 0; i < sizeof(initfuncs)/sizeof(initfuncs[0]); i++)
  70                 if (initfuncs[i])
  71                         initfuncs[i]();
  72 }
  73
  74 struct fw3_ipt_handle *
  75 fw3_ipt_open(enum fw3_family family, enum fw3_table table)
  76 {
  77         struct fw3_ipt_handle *h;
  78
  79         h = fw3_alloc(sizeof(*h));
  80
  81         xtables_init();
  82
  83         if (family == FW3_FAMILY_V6)
  84         {
  85 #ifndef DISABLE_IPV6
  86                 h->family = FW3_FAMILY_V6;
  87                 h->table  = table;
  88                 h->handle = ip6tc_init(fw3_flag_names[table]);
  89
  90                 xtables_set_params(&xtg6);
  91                 xtables_set_nfproto(NFPROTO_IPV6);
  92 #endif
  93         }
  94         else
  95         {
  96                 h->family = FW3_FAMILY_V4;
  97                 h->table  = table;
  98                 h->handle = iptc_init(fw3_flag_names[table]);
  99
 100                 xtables_set_params(&xtg);
 101                 xtables_set_nfproto(NFPROTO_IPV4);
 102         }
 103
 104         if (!h->handle)
 105         {
 106                 free(h);
 107                 return NULL;
 108         }
 109
 110         fw3_xt_reset();
 111         fw3_init_extensions();
 112
 113         return h;
 114 }
 115
 116 static void
 117 debug(struct fw3_ipt_handle *h, const char *fmt, ...)
 118 {
 119         va_list ap;
 120
 121         printf("%s -t %s ", (h->family == FW3_FAMILY_V6) ? "ip6tables" : "iptables",
 122                             fw3_flag_names[h->table]);
 123
 124         va_start(ap, fmt);
 125         vprintf(fmt, ap);
 126         va_end(ap);
 127 }
 128
 129 void
 130 fw3_ipt_set_policy(struct fw3_ipt_handle *h, const char *chain,
 131                    enum fw3_flag policy)
 132 {
 133         if (fw3_pr_debug)
 134                 debug(h, "-P %s %s\n", chain, fw3_flag_names[policy]);
 135
 136 #ifndef DISABLE_IPV6
 137         if (h->family == FW3_FAMILY_V6)
 138                 ip6tc_set_policy(chain, fw3_flag_names[policy], NULL, h->handle);
 139         else
 140 #endif
 141                 iptc_set_policy(chain, fw3_flag_names[policy], NULL, h->handle);
 142 }
 143
 144 void
 145 fw3_ipt_flush_chain(struct fw3_ipt_handle *h, const char *chain)
 146 {
 147         if (fw3_pr_debug)
 148                 debug(h, "-F %s\n", chain);
 149
 150 #ifndef DISABLE_IPV6
 151         if (h->family == FW3_FAMILY_V6)
 152                 ip6tc_flush_entries(chain, h->handle);
 153         else
 154 #endif
 155                 iptc_flush_entries(chain, h->handle);
 156 }
 157
 158 static void
 159 delete_rules(struct fw3_ipt_handle *h, const char *target)
 160 {
 161         unsigned int num;
 162         const struct ipt_entry *e;
 163         const char *chain;
 164         const char *t;
 165         bool found;
 166
 167 #ifndef DISABLE_IPV6
 168         if (h->family == FW3_FAMILY_V6)
 169         {
 170                 for (chain = ip6tc_first_chain(h->handle);
 171                      chain != NULL;
 172                      chain = ip6tc_next_chain(h->handle))
 173                 {
 174                         do {
 175                                 found = false;
 176
 177                                 const struct ip6t_entry *e6;
 178                                 for (num = 0, e6 = ip6tc_first_rule(chain, h->handle);
 179                                          e6 != NULL;
 180                                          num++, e6 = ip6tc_next_rule(e6, h->handle))
 181                                 {
 182                                         t = ip6tc_get_target(e6, h->handle);
 183
 184                                         if (*t && !strcmp(t, target))
 185                                         {
 186                                                 if (fw3_pr_debug)
 187                                                         debug(h, "-D %s %u\n", chain, num + 1);
 188
 189                                                 ip6tc_delete_num_entry(chain, num, h->handle);
 190                                                 found = true;
 191                                                 break;
 192                                         }
 193                                 }
 194                         } while (found);
 195                 }
 196         }
 197         else
 198 #endif
 199         {
 200                 for (chain = iptc_first_chain(h->handle);
 201                      chain != NULL;
 202                      chain = iptc_next_chain(h->handle))
 203                 {
 204                         do {
 205                                 found = false;
 206
 207                                 for (num = 0, e = iptc_first_rule(chain, h->handle);
 208                                      e != NULL;
 209                                          num++, e = iptc_next_rule(e, h->handle))
 210                                 {
 211                                         t = iptc_get_target(e, h->handle);
 212
 213                                         if (*t && !strcmp(t, target))
 214                                         {
 215                                                 if (fw3_pr_debug)
 216                                                         debug(h, "-D %s %u\n", chain, num + 1);
 217
 218                                                 iptc_delete_num_entry(chain, num, h->handle);
 219                                                 found = true;
 220                                                 break;
 221                                         }
 222                                 }
 223                         } while (found);
 224                 }
 225         }
 226 }
 227
 228 void
 229 fw3_ipt_delete_chain(struct fw3_ipt_handle *h, const char *chain)
 230 {
 231         delete_rules(h, chain);
 232
 233         if (fw3_pr_debug)
 234                 debug(h, "-X %s\n", chain);
 235
 236 #ifndef DISABLE_IPV6
 237         if (h->family == FW3_FAMILY_V6)
 238                 ip6tc_delete_chain(chain, h->handle);
 239         else
 240 #endif
 241                 iptc_delete_chain(chain, h->handle);
 242 }
 243
 244 void
 245 fw3_ipt_create_chain(struct fw3_ipt_handle *h, const char *fmt, ...)
 246 {
 247         char buf[32];
 248         va_list ap;
 249
 250         va_start(ap, fmt);
 251         vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
 252         va_end(ap);
 253
 254         if (fw3_pr_debug)
 255                 debug(h, "-N %s\n", buf);
 256
 257         iptc_create_chain(buf, h->handle);
 258 }
 259
 260 void
 261 fw3_ipt_flush(struct fw3_ipt_handle *h)
 262 {
 263         const char *chain;
 264
 265 #ifndef DISABLE_IPV6
 266         if (h->family == FW3_FAMILY_V6)
 267         {
 268                 for (chain = ip6tc_first_chain(h->handle);
 269                      chain != NULL;
 270                      chain = ip6tc_next_chain(h->handle))
 271                 {
 272                         ip6tc_flush_entries(chain, h->handle);
 273                 }
 274
 275                 for (chain = ip6tc_first_chain(h->handle);
 276                      chain != NULL;
 277                      chain = ip6tc_next_chain(h->handle))
 278                 {
 279                         ip6tc_delete_chain(chain, h->handle);
 280                 }
 281         }
 282         else
 283 #endif
 284         {
 285                 for (chain = iptc_first_chain(h->handle);
 286                      chain != NULL;
 287                      chain = iptc_next_chain(h->handle))
 288                 {
 289                         iptc_flush_entries(chain, h->handle);
 290                 }
 291
 292                 for (chain = iptc_first_chain(h->handle);
 293                      chain != NULL;
 294                      chain = iptc_next_chain(h->handle))
 295                 {
 296                         iptc_delete_chain(chain, h->handle);
 297                 }
 298         }
 299 }
 300
 301 void
 302 fw3_ipt_commit(struct fw3_ipt_handle *h)
 303 {
 304         int rv;
 305
 306 #ifndef DISABLE_IPV6
 307         if (h->family == FW3_FAMILY_V6)
 308         {
 309                 rv = ip6tc_commit(h->handle);
 310                 if (!rv)
 311                         warn("ip6tc_commit(): %s", ip6tc_strerror(errno));
 312         }
 313         else
 314 #endif
 315         {
 316                 rv = iptc_commit(h->handle);
 317                 if (!rv)
 318                         warn("iptc_commit(): %s", iptc_strerror(errno));
 319         }
 320 }
 321
 322 void
 323 fw3_ipt_close(struct fw3_ipt_handle *h)
 324 {
 325         if (h->libv)
 326         {
 327                 while (h->libc > 0)
 328                 {
 329                         h->libc--;
 330                         dlclose(h->libv[h->libc]);
 331                 }
 332
 333                 free(h->libv);
 334         }
 335
 336         free(h);
 337 }
 338
 339 struct fw3_ipt_rule *
 340 fw3_ipt_rule_new(struct fw3_ipt_handle *h)
 341 {
 342         struct fw3_ipt_rule *r;
 343
 344         r = fw3_alloc(sizeof(*r));
 345
 346         r->h = h;
 347         r->argv = fw3_alloc(sizeof(char *));
 348         r->argv[r->argc++] = "fw3";
 349
 350         return r;
 351 }
 352
 353
 354 static bool
 355 is_chain(struct fw3_ipt_handle *h, const char *name)
 356 {
 357 #ifndef DISABLE_IPV6
 358         if (h->family == FW3_FAMILY_V6)
 359                 return ip6tc_is_chain(name, h->handle);
 360         else
 361 #endif
 362                 return iptc_is_chain(name, h->handle);
 363 }
 364
 365 static char *
 366 get_protoname(struct fw3_ipt_rule *r)
 367 {
 368         const struct xtables_pprot *pp;
 369
 370         if (r->protocol)
 371                 for (pp = xtables_chain_protos; pp->name; pp++)
 372                         if (pp->num == r->protocol)
 373                                 return (char *)pp->name;
 374
 375         return NULL;
 376 }
 377
 378 static bool
 379 load_extension(struct fw3_ipt_handle *h, const char *name)
 380 {
 381         char path[256];
 382         void *lib, **tmp;
 383         const char *pfx = (h->family == FW3_FAMILY_V6) ? "libip6t" : "libipt";
 384
 385         snprintf(path, sizeof(path), "/usr/lib/iptables/libxt_%s.so", name);
 386         if (!(lib = dlopen(path, RTLD_NOW)))
 387         {
 388                 snprintf(path, sizeof(path), "/usr/lib/iptables/%s_%s.so", pfx, name);
 389                 lib = dlopen(path, RTLD_NOW);
 390         }
 391
 392         if (!lib)
 393                 return false;
 394
 395         tmp = realloc(h->libv, sizeof(lib) * (h->libc + 1));
 396
 397         if (!tmp)
 398                 return false;
 399
 400         h->libv = tmp;
 401         h->libv[h->libc++] = lib;
 402
 403         return true;
 404 }
 405
 406 static struct xtables_match *
 407 find_match(struct fw3_ipt_rule *r, const char *name)
 408 {
 409         struct xtables_match *m;
 410
 411         m = xtables_find_match(name, XTF_DONT_LOAD, &r->matches);
 412
 413         if (!m && load_extension(r->h, name))
 414                 m = xtables_find_match(name, XTF_DONT_LOAD, &r->matches);
 415
 416         return m;
 417 }
 418
 419 static void
 420 init_match(struct fw3_ipt_rule *r, struct xtables_match *m, bool no_clone)
 421 {
 422         size_t s;
 423         struct xtables_globals *g;
 424
 425         if (!m)
 426                 return;
 427
 428         s = XT_ALIGN(sizeof(struct xt_entry_match)) + m->size;
 429
 430         m->m = fw3_alloc(s);
 431
 432         fw3_xt_set_match_name(m);
 433
 434         m->m->u.user.revision = m->revision;
 435         m->m->u.match_size = s;
 436
 437         /* free previous userspace data */
 438         fw3_xt_free_match_udata(m);
 439
 440         if (m->init)
 441                 m->init(m->m);
 442
 443         /* don't merge options if no_clone is set and this match is a clone */
 444         if (no_clone && (m == m->next))
 445                 return;
 446
 447         /* merge option table */
 448         g = (r->h->family == FW3_FAMILY_V6) ? &xtg6 : &xtg;
 449         fw3_xt_merge_match_options(g, m);
 450 }
 451
 452 static bool
 453 need_protomatch(struct fw3_ipt_rule *r, const char *pname)
 454 {
 455         if (!pname)
 456                 return false;
 457
 458         if (!xtables_find_match(pname, XTF_DONT_LOAD, NULL))
 459                 return true;
 460
 461         return !r->protocol_loaded;
 462 }
 463
 464 static struct xtables_match *
 465 load_protomatch(struct fw3_ipt_rule *r)
 466 {
 467         const char *pname = get_protoname(r);
 468
 469         if (!need_protomatch(r, pname))
 470                 return NULL;
 471
 472         return find_match(r, pname);
 473 }
 474
 475 static struct xtables_target *
 476 find_target(struct fw3_ipt_rule *r, const char *name)
 477 {
 478         struct xtables_target *t;
 479
 480         if (is_chain(r->h, name))
 481                 return xtables_find_target(XT_STANDARD_TARGET, XTF_LOAD_MUST_SUCCEED);
 482
 483         t = xtables_find_target(name, XTF_DONT_LOAD);
 484
 485         if (!t && load_extension(r->h, name))
 486                 t = xtables_find_target(name, XTF_DONT_LOAD);
 487
 488         return t;
 489 }
 490
 491 static struct xtables_target *
 492 get_target(struct fw3_ipt_rule *r, const char *name)
 493 {
 494         size_t s;
 495         struct xtables_target *t;
 496         struct xtables_globals *g;
 497
 498         t = find_target(r, name);
 499
 500         if (!t)
 501                 return NULL;
 502
 503         s = XT_ALIGN(sizeof(struct xt_entry_target)) + t->size;
 504         t->t = fw3_alloc(s);
 505
 506         fw3_xt_set_target_name(t, name);
 507
 508         t->t->u.user.revision = t->revision;
 509         t->t->u.target_size = s;
 510
 511         /* free previous userspace data */
 512         fw3_xt_free_target_udata(t);
 513
 514         if (t->init)
 515                 t->init(t->t);
 516
 517         /* merge option table */
 518         g = (r->h->family == FW3_FAMILY_V6) ? &xtg6 : &xtg;
 519         fw3_xt_merge_target_options(g, t);
 520
 521         r->target = t;
 522
 523         return t;
 524 }
 525
 526 void
 527 fw3_ipt_rule_proto(struct fw3_ipt_rule *r, struct fw3_protocol *proto)
 528 {
 529         uint32_t pr;
 530
 531         if (!proto || proto->any)
 532                 return;
 533
 534         pr = proto->protocol;
 535
 536 #ifndef DISABLE_IPV6
 537         if (r->h->family == FW3_FAMILY_V6)
 538         {
 539                 if (pr == 1)
 540                         pr = 58;
 541
 542                 r->e6.ipv6.proto = pr;
 543                 r->e6.ipv6.flags |= IP6T_F_PROTO;
 544
 545                 if (proto->invert)
 546                         r->e6.ipv6.invflags |= XT_INV_PROTO;
 547         }
 548         else
 549 #endif
 550         {
 551                 r->e.ip.proto = pr;
 552
 553                 if (proto->invert)
 554                         r->e.ip.invflags |= XT_INV_PROTO;
 555         }
 556
 557         r->protocol = pr;
 558 }
 559
 560 void
 561 fw3_ipt_rule_in_out(struct fw3_ipt_rule *r,
 562                     struct fw3_device *in, struct fw3_device *out)
 563 {
 564 #ifndef DISABLE_IPV6
 565         if (r->h->family == FW3_FAMILY_V6)
 566         {
 567                 if (in && !in->any)
 568                 {
 569                         xtables_parse_interface(in->name, r->e6.ipv6.iniface,
 570                                                           r->e6.ipv6.iniface_mask);
 571
 572                         if (in->invert)
 573                                 r->e6.ipv6.invflags |= IP6T_INV_VIA_IN;
 574                 }
 575
 576                 if (out && !out->any)
 577                 {
 578                         xtables_parse_interface(out->name, r->e6.ipv6.outiface,
 579                                                            r->e6.ipv6.outiface_mask);
 580
 581                         if (out->invert)
 582                                 r->e6.ipv6.invflags |= IP6T_INV_VIA_OUT;
 583                 }
 584         }
 585         else
 586 #endif
 587         {
 588                 if (in && !in->any)
 589                 {
 590                         xtables_parse_interface(in->name, r->e.ip.iniface,
 591                                                           r->e.ip.iniface_mask);
 592
 593                         if (in->invert)
 594                                 r->e.ip.invflags |= IPT_INV_VIA_IN;
 595                 }
 596
 597                 if (out && !out->any)
 598                 {
 599                         xtables_parse_interface(out->name, r->e.ip.outiface,
 600                                                            r->e.ip.outiface_mask);
 601
 602                         if (out->invert)
 603                                 r->e.ip.invflags |= IPT_INV_VIA_OUT;
 604                 }
 605         }
 606 }
 607
 608
 609 static void
 610 ip4prefix2mask(int prefix, struct in_addr *mask)
 611 {
 612         if (prefix > 0)
 613                 mask->s_addr = htonl(~((1 << (32 - prefix)) - 1));
 614         else
 615                 mask->s_addr = 0;
 616 }
 617
 618 #ifndef DISABLE_IPV6
 619 static void
 620 ip6prefix2mask(int prefix, struct in6_addr *mask)
 621 {
 622         char *p = (char *)mask;
 623
 624         if (prefix > 0)
 625         {
 626                 memset(p, 0xff, prefix / 8);
 627                 memset(p + (prefix / 8) + 1, 0, (128 - prefix) / 8);
 628                 p[prefix / 8] = 0xff << (8 - (prefix & 7));
 629         }
 630         else
 631         {
 632                 memset(mask, 0, sizeof(*mask));
 633         }
 634 }
 635 #endif
 636
 637 void
 638 fw3_ipt_rule_src_dest(struct fw3_ipt_rule *r,
 639                       struct fw3_address *src, struct fw3_address *dest)
 640 {
 641         if ((src && src->range) || (dest && dest->range))
 642         {
 643                 fw3_ipt_rule_addarg(r, false, "-m", "iprange");
 644         }
 645
 646         if (src && src->set)
 647         {
 648                 if (src->range)
 649                 {
 650                         fw3_ipt_rule_addarg(r, src->invert, "--src-range",
 651                                             fw3_address_to_string(src, false));
 652                 }
 653 #ifndef DISABLE_IPV6
 654                 else if (r->h->family == FW3_FAMILY_V6)
 655                 {
 656                         r->e6.ipv6.src = src->address.v6;
 657                         ip6prefix2mask(src->mask, &r->e6.ipv6.smsk);
 658
 659                         int i;
 660                         for (i = 0; i < 4; i++)
 661                                 r->e6.ipv6.src.s6_addr32[i] &= r->e6.ipv6.smsk.s6_addr32[i];
 662
 663                         if (src->invert)
 664                                 r->e6.ipv6.invflags |= IP6T_INV_SRCIP;
 665                 }
 666 #endif
 667                 else
 668                 {
 669                         r->e.ip.src = src->address.v4;
 670                         ip4prefix2mask(src->mask, &r->e.ip.smsk);
 671
 672                         r->e.ip.src.s_addr &= r->e.ip.smsk.s_addr;
 673
 674                         if (src->invert)
 675                                 r->e.ip.invflags |= IPT_INV_SRCIP;
 676                 }
 677         }
 678
 679         if (dest && dest->set)
 680         {
 681                 if (dest->range)
 682                 {
 683                         fw3_ipt_rule_addarg(r, dest->invert, "--dst-range",
 684                                             fw3_address_to_string(dest, false));
 685                 }
 686 #ifndef DISABLE_IPV6
 687                 else if (r->h->family == FW3_FAMILY_V6)
 688                 {
 689                         r->e6.ipv6.dst = dest->address.v6;
 690                         ip6prefix2mask(dest->mask, &r->e6.ipv6.dmsk);
 691
 692                         int i;
 693                         for (i = 0; i < 4; i++)
 694                                 r->e6.ipv6.dst.s6_addr32[i] &= r->e6.ipv6.dmsk.s6_addr32[i];
 695
 696                         if (dest->invert)
 697                                 r->e6.ipv6.invflags |= IP6T_INV_DSTIP;
 698                 }
 699 #endif
 700                 else
 701                 {
 702                         r->e.ip.dst = dest->address.v4;
 703                         ip4prefix2mask(dest->mask, &r->e.ip.dmsk);
 704
 705                         r->e.ip.dst.s_addr &= r->e.ip.dmsk.s_addr;
 706
 707                         if (dest->invert)
 708                                 r->e.ip.invflags |= IPT_INV_DSTIP;
 709                 }
 710         }
 711 }
 712
 713 void
 714 fw3_ipt_rule_sport_dport(struct fw3_ipt_rule *r,
 715                          struct fw3_port *sp, struct fw3_port *dp)
 716 {
 717         char buf[sizeof("65535:65535\0")];
 718
 719         if ((!sp || !sp->set) && (!dp || !dp->set))
 720                 return;
 721
 722         if (!get_protoname(r))
 723                 return;
 724
 725         if (sp && sp->set)
 726         {
 727                 if (sp->port_min == sp->port_max)
 728                         sprintf(buf, "%u", sp->port_min);
 729                 else
 730                         sprintf(buf, "%u:%u", sp->port_min, sp->port_max);
 731
 732                 fw3_ipt_rule_addarg(r, sp->invert, "--sport", buf);
 733         }
 734
 735         if (dp && dp->set)
 736         {
 737                 if (dp->port_min == dp->port_max)
 738                         sprintf(buf, "%u", dp->port_min);
 739                 else
 740                         sprintf(buf, "%u:%u", dp->port_min, dp->port_max);
 741
 742                 fw3_ipt_rule_addarg(r, dp->invert, "--dport", buf);
 743         }
 744 }
 745
 746 void
 747 fw3_ipt_rule_mac(struct fw3_ipt_rule *r, struct fw3_mac *mac)
 748 {
 749         if (!mac)
 750                 return;
 751
 752         fw3_ipt_rule_addarg(r, false, "-m", "mac");
 753         fw3_ipt_rule_addarg(r, mac->invert, "--mac-source", ether_ntoa(&mac->mac));
 754 }
 755
 756 void
 757 fw3_ipt_rule_icmptype(struct fw3_ipt_rule *r, struct fw3_icmptype *icmp)
 758 {
 759         char buf[sizeof("255/255\0")];
 760
 761         if (!icmp)
 762                 return;
 763
 764 #ifndef DISABLE_IPV6
 765         if (r->h->family == FW3_FAMILY_V6)
 766         {
 767                 if (icmp->code6_min == 0 && icmp->code6_max == 0xFF)
 768                         sprintf(buf, "%u", icmp->type6);
 769                 else
 770                         sprintf(buf, "%u/%u", icmp->type6, icmp->code6_min);
 771
 772                 fw3_ipt_rule_addarg(r, icmp->invert, "--icmpv6-type", buf);
 773         }
 774         else
 775 #endif
 776         {
 777                 if (icmp->code_min == 0 && icmp->code_max == 0xFF)
 778                         sprintf(buf, "%u", icmp->type);
 779                 else
 780                         sprintf(buf, "%u/%u", icmp->type, icmp->code_min);
 781
 782                 fw3_ipt_rule_addarg(r, icmp->invert, "--icmp-type", buf);
 783         }
 784 }
 785
 786 void
 787 fw3_ipt_rule_limit(struct fw3_ipt_rule *r, struct fw3_limit *limit)
 788 {
 789         char buf[sizeof("-4294967296/second\0")];
 790
 791         if (!limit || limit->rate <= 0)
 792                 return;
 793
 794         fw3_ipt_rule_addarg(r, false, "-m", "limit");
 795
 796         sprintf(buf, "%u/%s", limit->rate, fw3_limit_units[limit->unit]);
 797         fw3_ipt_rule_addarg(r, limit->invert, "--limit", buf);
 798
 799         if (limit->burst > 0)
 800         {
 801                 sprintf(buf, "%u", limit->burst);
 802                 fw3_ipt_rule_addarg(r, limit->invert, "--limit-burst", buf);
 803         }
 804 }
 805
 806 void
 807 fw3_ipt_rule_ipset(struct fw3_ipt_rule *r, struct fw3_setmatch *match)
 808 {
 809         char buf[sizeof("dst,dst,dst\0")];
 810         char *p = buf;
 811         int i = 0;
 812
 813         struct fw3_ipset *set;
 814         struct fw3_ipset_datatype *type;
 815
 816         if (!match || !match->set || !match->ptr)
 817                 return;
 818
 819         set = match->ptr;
 820         list_for_each_entry(type, &set->datatypes, list)
 821         {
 822                 if (i >= 3)
 823                         break;
 824
 825                 if (p > buf)
 826                         *p++ = ',';
 827
 828                 p += sprintf(p, "%s", match->dir[i] ? match->dir[i] : type->dir);
 829                 i++;
 830         }
 831
 832         fw3_ipt_rule_addarg(r, false, "-m", "set");
 833
 834         fw3_ipt_rule_addarg(r, match->invert, "--match-set",
 835                             set->external ? set->external : set->name);
 836
 837         fw3_ipt_rule_addarg(r, false, buf, NULL);
 838 }
 839
 840 void
 841 fw3_ipt_rule_time(struct fw3_ipt_rule *r, struct fw3_time *time)
 842 {
 843         int i;
 844         struct tm empty = { 0 };
 845
 846         char buf[84]; /* sizeof("1,2,3,...,30,31\0") */
 847         char *p;
 848
 849         bool d1 = memcmp(&time->datestart, &empty, sizeof(empty));
 850         bool d2 = memcmp(&time->datestop, &empty, sizeof(empty));
 851
 852         if (!d1 && !d2 && !time->timestart && !time->timestop &&
 853             !(time->monthdays & 0xFFFFFFFE) && !(time->weekdays & 0xFE))
 854         {
 855                 return;
 856         }
 857
 858         fw3_ipt_rule_addarg(r, false, "-m", "time");
 859
 860         if (time->utc)
 861                 fw3_ipt_rule_addarg(r, false, "--utc", NULL);
 862
 863         if (d1)
 864         {
 865                 strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%S", &time->datestart);
 866                 fw3_ipt_rule_addarg(r, false, "--datestart", buf);
 867         }
 868
 869         if (d2)
 870         {
 871                 strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%S", &time->datestop);
 872                 fw3_ipt_rule_addarg(r, false, "--datestop", buf);
 873         }
 874
 875         if (time->timestart)
 876         {
 877                 sprintf(buf, "%02d:%02d:%02d",
 878                         time->timestart / 3600,
 879                         time->timestart % 3600 / 60,
 880                         time->timestart % 60);
 881
 882                 fw3_ipt_rule_addarg(r, false, "--timestart", buf);
 883         }
 884
 885         if (time->timestop)
 886         {
 887                 sprintf(buf, "%02d:%02d:%02d",
 888                         time->timestop / 3600,
 889                         time->timestop % 3600 / 60,
 890                         time->timestop % 60);
 891
 892                 fw3_ipt_rule_addarg(r, false, "--timestop", buf);
 893         }
 894
 895         if (time->monthdays & 0xFFFFFFFE)
 896         {
 897                 for (i = 1, p = buf; i < 32; i++)
 898                 {
 899                         if (hasbit(time->monthdays, i))
 900                         {
 901                                 if (p > buf)
 902                                         *p++ = ',';
 903
 904                                 p += sprintf(p, "%u", i);
 905                         }
 906                 }
 907
 908                 fw3_ipt_rule_addarg(r, hasbit(time->monthdays, 0), "--monthdays", buf);
 909         }
 910
 911         if (time->weekdays & 0xFE)
 912         {
 913                 for (i = 1, p = buf; i < 8; i++)
 914                 {
 915                         if (hasbit(time->weekdays, i))
 916                         {
 917                                 if (p > buf)
 918                                         *p++ = ',';
 919
 920                                 p += sprintf(p, "%u", i);
 921                         }
 922                 }
 923
 924                 fw3_ipt_rule_addarg(r, hasbit(time->weekdays, 0), "--weekdays", buf);
 925         }
 926 }
 927
 928 void
 929 fw3_ipt_rule_mark(struct fw3_ipt_rule *r, struct fw3_mark *mark)
 930 {
 931         char buf[sizeof("0xFFFFFFFF/0xFFFFFFFF\0")];
 932
 933         if (!mark || !mark->set)
 934                 return;
 935
 936         if (mark->mask < 0xFFFFFFFF)
 937                 sprintf(buf, "0x%x/0x%x", mark->mark, mark->mask);
 938         else
 939                 sprintf(buf, "0x%x", mark->mark);
 940
 941         fw3_ipt_rule_addarg(r, false, "-m", "mark");
 942         fw3_ipt_rule_addarg(r, mark->invert, "--mark", buf);
 943 }
 944
 945 void
 946 fw3_ipt_rule_comment(struct fw3_ipt_rule *r, const char *fmt, ...)
 947 {
 948         va_list ap;
 949         char buf[256];
 950
 951         if (!fmt || !*fmt)
 952                 return;
 953
 954         va_start(ap, fmt);
 955         vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
 956         va_end(ap);
 957
 958         fw3_ipt_rule_addarg(r, false, "-m", "comment");
 959         fw3_ipt_rule_addarg(r, false, "--comment", buf);
 960 }
 961
 962 void
 963 fw3_ipt_rule_extra(struct fw3_ipt_rule *r, const char *extra)
 964 {
 965         char *p, **tmp, *s;
 966
 967         if (!extra || !*extra)
 968                 return;
 969
 970         s = fw3_strdup(extra);
 971
 972         for (p = strtok(s, " \t"); p; p = strtok(NULL, " \t"))
 973         {
 974                 tmp = realloc(r->argv, (r->argc + 1) * sizeof(*r->argv));
 975
 976                 if (!tmp)
 977                         break;
 978
 979                 r->argv = tmp;
 980                 r->argv[r->argc++] = fw3_strdup(p);
 981         }
 982
 983         free(s);
 984 }
 985
 986 #ifndef DISABLE_IPV6
 987 static void
 988 rule_print6(struct ip6t_entry *e)
 989 {
 990         char buf[INET6_ADDRSTRLEN];
 991         char *pname;
 992
 993         if (e->ipv6.flags & IP6T_F_PROTO)
 994         {
 995                 if (e->ipv6.flags & XT_INV_PROTO)
 996                         printf(" !");
 997
 998                 pname = get_protoname(container_of(e, struct fw3_ipt_rule, e6));
 999
1000                 if (pname)
1001                         printf(" -p %s", pname);
1002                 else
1003                         printf(" -p %u", e->ipv6.proto);
1004         }
1005
1006         if (e->ipv6.iniface[0])
1007         {
1008                 if (e->ipv6.flags & IP6T_INV_VIA_IN)
1009                         printf(" !");
1010
1011                 printf(" -i %s", e->ipv6.iniface);
1012         }
1013
1014         if (e->ipv6.outiface[0])
1015         {
1016                 if (e->ipv6.flags & IP6T_INV_VIA_OUT)
1017                         printf(" !");
1018
1019                 printf(" -o %s", e->ipv6.outiface);
1020         }
1021
1022         if (memcmp(&e->ipv6.src, &in6addr_any, sizeof(struct in6_addr)))
1023         {
1024                 if (e->ipv6.flags & IP6T_INV_SRCIP)
1025                         printf(" !");
1026
1027                 printf(" -s %s/%u", inet_ntop(AF_INET6, &e->ipv6.src, buf, sizeof(buf)),
1028                                     xtables_ip6mask_to_cidr(&e->ipv6.smsk));
1029         }
1030
1031         if (memcmp(&e->ipv6.dst, &in6addr_any, sizeof(struct in6_addr)))
1032         {
1033                 if (e->ipv6.flags & IP6T_INV_DSTIP)
1034                         printf(" !");
1035
1036                 printf(" -d %s/%u", inet_ntop(AF_INET6, &e->ipv6.dst, buf, sizeof(buf)),
1037                                     xtables_ip6mask_to_cidr(&e->ipv6.dmsk));
1038         }
1039 }
1040 #endif
1041
1042 static void
1043 rule_print4(struct ipt_entry *e)
1044 {
1045         struct in_addr in_zero = { 0 };
1046         char buf[sizeof("255.255.255.255\0")];
1047         char *pname;
1048
1049         if (e->ip.proto)
1050         {
1051                 if (e->ip.flags & XT_INV_PROTO)
1052                         printf(" !");
1053
1054                 pname = get_protoname(container_of(e, struct fw3_ipt_rule, e));
1055
1056                 if (pname)
1057                         printf(" -p %s", pname);
1058                 else
1059                         printf(" -p %u", e->ip.proto);
1060         }
1061
1062         if (e->ip.iniface[0])
1063         {
1064                 if (e->ip.flags & IPT_INV_VIA_IN)
1065                         printf(" !");
1066
1067                 printf(" -i %s", e->ip.iniface);
1068         }
1069
1070         if (e->ip.outiface[0])
1071         {
1072                 if (e->ip.flags & IPT_INV_VIA_OUT)
1073                         printf(" !");
1074
1075                 printf(" -o %s", e->ip.outiface);
1076         }
1077
1078         if (memcmp(&e->ip.src, &in_zero, sizeof(struct in_addr)))
1079         {
1080                 if (e->ip.flags & IPT_INV_SRCIP)
1081                         printf(" !");
1082
1083                 printf(" -s %s/%u", inet_ntop(AF_INET, &e->ip.src, buf, sizeof(buf)),
1084                                     xtables_ipmask_to_cidr(&e->ip.smsk));
1085         }
1086
1087         if (memcmp(&e->ip.dst, &in_zero, sizeof(struct in_addr)))
1088         {
1089                 if (e->ip.flags & IPT_INV_DSTIP)
1090                         printf(" !");
1091
1092                 printf(" -d %s/%u", inet_ntop(AF_INET, &e->ip.dst, buf, sizeof(buf)),
1093                                     xtables_ipmask_to_cidr(&e->ip.dmsk));
1094         }
1095 }
1096
1097 static void
1098 rule_print(struct fw3_ipt_rule *r, const char *prefix, const char *chain)
1099 {
1100         debug(r->h, "%s %s", prefix, chain);
1101
1102 #ifndef DISABLE_IPV6
1103         if (r->h->family == FW3_FAMILY_V6)
1104                 rule_print6(&r->e6);
1105         else
1106 #endif
1107                 rule_print4(&r->e);
1108
1109         fw3_xt_print_matches(&r->e.ip, r->matches);
1110         fw3_xt_print_target(&r->e.ip, r->target);
1111
1112         printf("\n");
1113 }
1114
1115 static bool
1116 parse_option(struct fw3_ipt_rule *r, int optc, bool inv)
1117 {
1118         struct xtables_rule_match *m;
1119         struct xtables_match *em;
1120
1121         /* is a target option */
1122         if (r->target && fw3_xt_has_target_parse(r->target) &&
1123                 optc >= r->target->option_offset &&
1124                 optc < (r->target->option_offset + 256))
1125         {
1126                 xtables_option_tpcall(optc, r->argv, inv, r->target, &r->e);
1127                 return false;
1128         }
1129
1130         /* try to dispatch argument to one of the match parsers */
1131         for (m = r->matches; m; m = m->next)
1132         {
1133                 em = m->match;
1134
1135                 if (m->completed || !fw3_xt_has_match_parse(em))
1136                         continue;
1137
1138                 if (optc < em->option_offset ||
1139                         optc >= (em->option_offset + 256))
1140                         continue;
1141
1142                 xtables_option_mpcall(optc, r->argv, inv, em, &r->e);
1143                 return false;
1144         }
1145
1146         /* unhandled option, might belong to a protocol match */
1147         if ((em = load_protomatch(r)) != NULL)
1148         {
1149                 init_match(r, em, false);
1150
1151                 r->protocol_loaded = true;
1152                 optind--;
1153
1154                 return true;
1155         }
1156
1157         if (optc == ':')
1158                 warn("parse_option(): option '%s' needs argument", r->argv[optind-1]);
1159
1160         if (optc == '?')
1161                 warn("parse_option(): unknown option '%s'", r->argv[optind-1]);
1162
1163         return false;
1164 }
1165
1166 void
1167 fw3_ipt_rule_addarg(struct fw3_ipt_rule *r, bool inv,
1168                     const char *k, const char *v)
1169 {
1170         int n;
1171         char **tmp;
1172
1173         if (!k)
1174                 return;
1175
1176         n = inv + !!k + !!v;
1177         tmp = realloc(r->argv, (r->argc + n) * sizeof(*tmp));
1178
1179         if (!tmp)
1180                 return;
1181
1182         r->argv = tmp;
1183
1184         if (inv)
1185                 r->argv[r->argc++] = fw3_strdup("!");
1186
1187         r->argv[r->argc++] = fw3_strdup(k);
1188
1189         if (v)
1190                 r->argv[r->argc++] = fw3_strdup(v);
1191 }
1192
1193 static unsigned char *
1194 rule_mask(struct fw3_ipt_rule *r)
1195 {
1196         size_t s;
1197         unsigned char *p, *mask = NULL;
1198         struct xtables_rule_match *m;
1199
1200 #define SZ(x) XT_ALIGN(sizeof(struct x))
1201
1202 #ifndef DISABLE_IPV6
1203         if (r->h->family == FW3_FAMILY_V6)
1204         {
1205                 s = SZ(ip6t_entry);
1206
1207                 for (m = r->matches; m; m = m->next)
1208                         s += SZ(ip6t_entry_match) + m->match->size;
1209
1210                 s += SZ(ip6t_entry_target) + r->target->size;
1211
1212                 mask = fw3_alloc(s);
1213                 memset(mask, 0xFF, SZ(ip6t_entry));
1214                 p = mask + SZ(ip6t_entry);
1215
1216                 for (m = r->matches; m; m = m->next)
1217                 {
1218                         memset(p, 0xFF, SZ(ip6t_entry_match) + m->match->userspacesize);
1219                         p += SZ(ip6t_entry_match) + m->match->size;
1220                 }
1221
1222                 memset(p, 0xFF, SZ(ip6t_entry_target) + r->target->userspacesize);
1223         }
1224         else
1225 #endif
1226         {
1227                 s = SZ(ipt_entry);
1228
1229                 for (m = r->matches; m; m = m->next)
1230                         s += SZ(ipt_entry_match) + m->match->size;
1231
1232                 s += SZ(ipt_entry_target) + r->target->size;
1233
1234                 mask = fw3_alloc(s);
1235                 memset(mask, 0xFF, SZ(ipt_entry));
1236                 p = mask + SZ(ipt_entry);
1237
1238                 for (m = r->matches; m; m = m->next)
1239                 {
1240                         memset(p, 0xFF, SZ(ipt_entry_match) + m->match->userspacesize);
1241                         p += SZ(ipt_entry_match) + m->match->size;
1242                 }
1243
1244                 memset(p, 0xFF, SZ(ipt_entry_target) + r->target->userspacesize);
1245         }
1246
1247         return mask;
1248 }
1249
1250 static void *
1251 rule_build(struct fw3_ipt_rule *r)
1252 {
1253         size_t s;
1254         struct xtables_rule_match *m;
1255
1256 #ifndef DISABLE_IPV6
1257         if (r->h->family == FW3_FAMILY_V6)
1258         {
1259                 struct ip6t_entry *e6;
1260
1261                 s = XT_ALIGN(sizeof(struct ip6t_entry));
1262
1263                 for (m = r->matches; m; m = m->next)
1264                         s += m->match->m->u.match_size;
1265
1266                 e6 = fw3_alloc(s + r->target->t->u.target_size);
1267
1268                 memcpy(e6, &r->e6, sizeof(struct ip6t_entry));
1269
1270                 e6->target_offset = s;
1271                 e6->next_offset = s + r->target->t->u.target_size;
1272
1273                 s = 0;
1274
1275                 for (m = r->matches; m; m = m->next)
1276                 {
1277                         memcpy(e6->elems + s, m->match->m, m->match->m->u.match_size);
1278                         s += m->match->m->u.match_size;
1279                 }
1280
1281                 memcpy(e6->elems + s, r->target->t, r->target->t->u.target_size);
1282
1283                 return e6;
1284         }
1285         else
1286 #endif
1287         {
1288                 struct ipt_entry *e;
1289
1290                 s = XT_ALIGN(sizeof(struct ipt_entry));
1291
1292                 for (m = r->matches; m; m = m->next)
1293                         s += m->match->m->u.match_size;
1294
1295                 e = fw3_alloc(s + r->target->t->u.target_size);
1296
1297                 memcpy(e, &r->e, sizeof(struct ipt_entry));
1298
1299                 e->target_offset = s;
1300                 e->next_offset = s + r->target->t->u.target_size;
1301
1302                 s = 0;
1303
1304                 for (m = r->matches; m; m = m->next)
1305                 {
1306                         memcpy(e->elems + s, m->match->m, m->match->m->u.match_size);
1307                         s += m->match->m->u.match_size;
1308                 }
1309
1310                 memcpy(e->elems + s, r->target->t, r->target->t->u.target_size);
1311
1312                 return e;
1313         }
1314 }
1315
1316 void
1317 __fw3_ipt_rule_append(struct fw3_ipt_rule *r, bool repl, const char *fmt, ...)
1318 {
1319         void *rule;
1320         unsigned char *mask;
1321
1322         struct xtables_rule_match *m;
1323         struct xtables_match *em;
1324         struct xtables_target *et;
1325         struct xtables_globals *g;
1326
1327         int i, optc;
1328         bool inv = false;
1329         char buf[32];
1330         va_list ap;
1331
1332         va_start(ap, fmt);
1333         vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
1334         va_end(ap);
1335
1336         g = (r->h->family == FW3_FAMILY_V6) ? &xtg6 : &xtg;
1337         g->opts = g->orig_opts;
1338
1339         optind = 0;
1340         opterr = 0;
1341
1342         while ((optc = getopt_long(r->argc, r->argv, "-:m:j:", g->opts,
1343                                    NULL)) != -1)
1344         {
1345                 switch (optc)
1346                 {
1347                 case 'm':
1348                         em = find_match(r, optarg);
1349
1350                         if (!em)
1351                         {
1352                                 warn("fw3_ipt_rule_append(): Can't find match '%s'", optarg);
1353                                 goto free;
1354                         }
1355
1356                         init_match(r, em, true);
1357                         break;
1358
1359                 case 'j':
1360                         et = get_target(r, optarg);
1361
1362                         if (!et)
1363                         {
1364                                 warn("fw3_ipt_rule_append(): Can't find target '%s'", optarg);
1365                                 goto free;
1366                         }
1367
1368                         break;
1369
1370                 case 1:
1371                         if ((optarg[0] == '!') && (optarg[1] == '\0'))
1372                         {
1373                                 optarg[0] = '\0';
1374                                 inv = true;
1375                                 continue;
1376                         }
1377
1378                         warn("fw3_ipt_rule_append(): Bad argument '%s'", optarg);
1379                         goto free;
1380
1381                 default:
1382                         if (parse_option(r, optc, inv))
1383                                 continue;
1384                         break;
1385                 }
1386
1387                 inv = false;
1388         }
1389
1390         for (m = r->matches; m; m = m->next)
1391                 xtables_option_mfcall(m->match);
1392
1393         if (r->target)
1394                 xtables_option_tfcall(r->target);
1395
1396         rule = rule_build(r);
1397
1398 #ifndef DISABLE_IPV6
1399         if (r->h->family == FW3_FAMILY_V6)
1400         {
1401                 if (repl)
1402                 {
1403                         mask = rule_mask(r);
1404
1405                         while (ip6tc_delete_entry(buf, rule, mask, r->h->handle))
1406                                 if (fw3_pr_debug)
1407                                         rule_print(r, "-D", buf);
1408
1409                         free(mask);
1410                 }
1411
1412                 if (fw3_pr_debug)
1413                         rule_print(r, "-A", buf);
1414
1415                 if (!ip6tc_append_entry(buf, rule, r->h->handle))
1416                         warn("ip6tc_append_entry(): %s", ip6tc_strerror(errno));
1417         }
1418         else
1419 #endif
1420         {
1421                 if (repl)
1422                 {
1423                         mask = rule_mask(r);
1424
1425                         while (iptc_delete_entry(buf, rule, mask, r->h->handle))
1426                                 if (fw3_pr_debug)
1427                                         rule_print(r, "-D", buf);
1428
1429                         free(mask);
1430                 }
1431
1432                 if (fw3_pr_debug)
1433                         rule_print(r, "-A", buf);
1434
1435                 if (!iptc_append_entry(buf, rule, r->h->handle))
1436                         warn("iptc_append_entry(): %s\n", iptc_strerror(errno));
1437         }
1438
1439         free(rule);
1440
1441 free:
1442         for (i = 1; i < r->argc; i++)
1443                 free(r->argv[i]);
1444
1445         free(r->argv);
1446
1447         xtables_rule_matches_free(&r->matches);
1448
1449         if (r->target)
1450                 free(r->target->t);
1451
1452         free(r);
1453
1454         /* reset all targets and matches */
1455         for (em = xtables_matches; em; em = em->next)
1456                 em->mflags = 0;
1457
1458         for (et = xtables_targets; et; et = et->next)
1459         {
1460                 et->tflags = 0;
1461                 et->used = 0;
1462         }
1463
1464         xtables_free_opts(1);
1465 }
1466
1467 struct fw3_ipt_rule *
1468 fw3_ipt_rule_create(struct fw3_ipt_handle *handle, struct fw3_protocol *proto,
1469                     struct fw3_device *in, struct fw3_device *out,
1470                     struct fw3_address *src, struct fw3_address *dest)
1471 {
1472         struct fw3_ipt_rule *r;
1473
1474         r = fw3_ipt_rule_new(handle);
1475
1476         fw3_ipt_rule_proto(r, proto);
1477         fw3_ipt_rule_in_out(r, in, out);
1478         fw3_ipt_rule_src_dest(r, src, dest);
1479
1480         return r;
1481 }