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         mask->s_addr = htonl(~((1 << (32 - prefix)) - 1));
 613 }
 614
 615 #ifndef DISABLE_IPV6
 616 static void
 617 ip6prefix2mask(int prefix, struct in6_addr *mask)
 618 {
 619         char *p = (char *)mask;
 620
 621         if (prefix > 0)
 622         {
 623                 memset(p, 0xff, prefix / 8);
 624                 memset(p + (prefix / 8) + 1, 0, (128 - prefix) / 8);
 625                 p[prefix / 8] = 0xff << (8 - (prefix & 7));
 626         }
 627         else
 628         {
 629                 memset(mask, 0, sizeof(*mask));
 630         }
 631 }
 632 #endif
 633
 634 void
 635 fw3_ipt_rule_src_dest(struct fw3_ipt_rule *r,
 636                       struct fw3_address *src, struct fw3_address *dest)
 637 {
 638         if ((src && src->range) || (dest && dest->range))
 639         {
 640                 fw3_ipt_rule_addarg(r, false, "-m", "iprange");
 641         }
 642
 643         if (src && src->set)
 644         {
 645                 if (src->range)
 646                 {
 647                         fw3_ipt_rule_addarg(r, src->invert, "--src-range",
 648                                             fw3_address_to_string(src, false));
 649                 }
 650 #ifndef DISABLE_IPV6
 651                 else if (r->h->family == FW3_FAMILY_V6)
 652                 {
 653                         r->e6.ipv6.src = src->address.v6;
 654                         ip6prefix2mask(src->mask, &r->e6.ipv6.smsk);
 655
 656                         int i;
 657                         for (i = 0; i < 4; i++)
 658                                 r->e6.ipv6.src.s6_addr32[i] &= r->e6.ipv6.smsk.s6_addr32[i];
 659
 660                         if (src->invert)
 661                                 r->e6.ipv6.invflags |= IP6T_INV_SRCIP;
 662                 }
 663 #endif
 664                 else
 665                 {
 666                         r->e.ip.src = src->address.v4;
 667                         ip4prefix2mask(src->mask, &r->e.ip.smsk);
 668
 669                         r->e.ip.src.s_addr &= r->e.ip.smsk.s_addr;
 670
 671                         if (src->invert)
 672                                 r->e.ip.invflags |= IPT_INV_SRCIP;
 673                 }
 674         }
 675
 676         if (dest && dest->set)
 677         {
 678                 if (dest->range)
 679                 {
 680                         fw3_ipt_rule_addarg(r, dest->invert, "--dst-range",
 681                                             fw3_address_to_string(dest, false));
 682                 }
 683 #ifndef DISABLE_IPV6
 684                 else if (r->h->family == FW3_FAMILY_V6)
 685                 {
 686                         r->e6.ipv6.dst = dest->address.v6;
 687                         ip6prefix2mask(dest->mask, &r->e6.ipv6.dmsk);
 688
 689                         int i;
 690                         for (i = 0; i < 4; i++)
 691                                 r->e6.ipv6.dst.s6_addr32[i] &= r->e6.ipv6.dmsk.s6_addr32[i];
 692
 693                         if (dest->invert)
 694                                 r->e6.ipv6.invflags |= IP6T_INV_DSTIP;
 695                 }
 696 #endif
 697                 else
 698                 {
 699                         r->e.ip.dst = dest->address.v4;
 700                         ip4prefix2mask(dest->mask, &r->e.ip.dmsk);
 701
 702                         r->e.ip.dst.s_addr &= r->e.ip.dmsk.s_addr;
 703
 704                         if (dest->invert)
 705                                 r->e.ip.invflags |= IPT_INV_DSTIP;
 706                 }
 707         }
 708 }
 709
 710 void
 711 fw3_ipt_rule_sport_dport(struct fw3_ipt_rule *r,
 712                          struct fw3_port *sp, struct fw3_port *dp)
 713 {
 714         char buf[sizeof("65535:65535\0")];
 715
 716         if ((!sp || !sp->set) && (!dp || !dp->set))
 717                 return;
 718
 719         if (!get_protoname(r))
 720                 return;
 721
 722         if (sp && sp->set)
 723         {
 724                 if (sp->port_min == sp->port_max)
 725                         sprintf(buf, "%u", sp->port_min);
 726                 else
 727                         sprintf(buf, "%u:%u", sp->port_min, sp->port_max);
 728
 729                 fw3_ipt_rule_addarg(r, sp->invert, "--sport", buf);
 730         }
 731
 732         if (dp && dp->set)
 733         {
 734                 if (dp->port_min == dp->port_max)
 735                         sprintf(buf, "%u", dp->port_min);
 736                 else
 737                         sprintf(buf, "%u:%u", dp->port_min, dp->port_max);
 738
 739                 fw3_ipt_rule_addarg(r, dp->invert, "--dport", buf);
 740         }
 741 }
 742
 743 void
 744 fw3_ipt_rule_mac(struct fw3_ipt_rule *r, struct fw3_mac *mac)
 745 {
 746         if (!mac)
 747                 return;
 748
 749         fw3_ipt_rule_addarg(r, false, "-m", "mac");
 750         fw3_ipt_rule_addarg(r, mac->invert, "--mac-source", ether_ntoa(&mac->mac));
 751 }
 752
 753 void
 754 fw3_ipt_rule_icmptype(struct fw3_ipt_rule *r, struct fw3_icmptype *icmp)
 755 {
 756         char buf[sizeof("255/255\0")];
 757
 758         if (!icmp)
 759                 return;
 760
 761 #ifndef DISABLE_IPV6
 762         if (r->h->family == FW3_FAMILY_V6)
 763         {
 764                 if (icmp->code6_min == 0 && icmp->code6_max == 0xFF)
 765                         sprintf(buf, "%u", icmp->type6);
 766                 else
 767                         sprintf(buf, "%u/%u", icmp->type6, icmp->code6_min);
 768
 769                 fw3_ipt_rule_addarg(r, icmp->invert, "--icmpv6-type", buf);
 770         }
 771         else
 772 #endif
 773         {
 774                 if (icmp->code_min == 0 && icmp->code_max == 0xFF)
 775                         sprintf(buf, "%u", icmp->type);
 776                 else
 777                         sprintf(buf, "%u/%u", icmp->type, icmp->code_min);
 778
 779                 fw3_ipt_rule_addarg(r, icmp->invert, "--icmp-type", buf);
 780         }
 781 }
 782
 783 void
 784 fw3_ipt_rule_limit(struct fw3_ipt_rule *r, struct fw3_limit *limit)
 785 {
 786         char buf[sizeof("-4294967296/second\0")];
 787
 788         if (!limit || limit->rate <= 0)
 789                 return;
 790
 791         fw3_ipt_rule_addarg(r, false, "-m", "limit");
 792
 793         sprintf(buf, "%u/%s", limit->rate, fw3_limit_units[limit->unit]);
 794         fw3_ipt_rule_addarg(r, limit->invert, "--limit", buf);
 795
 796         if (limit->burst > 0)
 797         {
 798                 sprintf(buf, "%u", limit->burst);
 799                 fw3_ipt_rule_addarg(r, limit->invert, "--limit-burst", buf);
 800         }
 801 }
 802
 803 void
 804 fw3_ipt_rule_ipset(struct fw3_ipt_rule *r, struct fw3_setmatch *match)
 805 {
 806         char buf[sizeof("dst,dst,dst\0")];
 807         char *p = buf;
 808         int i = 0;
 809
 810         struct fw3_ipset *set;
 811         struct fw3_ipset_datatype *type;
 812
 813         if (!match || !match->set || !match->ptr)
 814                 return;
 815
 816         set = match->ptr;
 817         list_for_each_entry(type, &set->datatypes, list)
 818         {
 819                 if (i >= 3)
 820                         break;
 821
 822                 if (p > buf)
 823                         *p++ = ',';
 824
 825                 p += sprintf(p, "%s", match->dir[i] ? match->dir[i] : type->dir);
 826                 i++;
 827         }
 828
 829         fw3_ipt_rule_addarg(r, false, "-m", "set");
 830
 831         fw3_ipt_rule_addarg(r, match->invert, "--match-set",
 832                             set->external ? set->external : set->name);
 833
 834         fw3_ipt_rule_addarg(r, false, buf, NULL);
 835 }
 836
 837 void
 838 fw3_ipt_rule_time(struct fw3_ipt_rule *r, struct fw3_time *time)
 839 {
 840         int i;
 841         struct tm empty = { 0 };
 842
 843         char buf[84]; /* sizeof("1,2,3,...,30,31\0") */
 844         char *p;
 845
 846         bool d1 = memcmp(&time->datestart, &empty, sizeof(empty));
 847         bool d2 = memcmp(&time->datestop, &empty, sizeof(empty));
 848
 849         if (!d1 && !d2 && !time->timestart && !time->timestop &&
 850             !(time->monthdays & 0xFFFFFFFE) && !(time->weekdays & 0xFE))
 851         {
 852                 return;
 853         }
 854
 855         fw3_ipt_rule_addarg(r, false, "-m", "time");
 856
 857         if (time->utc)
 858                 fw3_ipt_rule_addarg(r, false, "--utc", NULL);
 859
 860         if (d1)
 861         {
 862                 strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%S", &time->datestart);
 863                 fw3_ipt_rule_addarg(r, false, "--datestart", buf);
 864         }
 865
 866         if (d2)
 867         {
 868                 strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%S", &time->datestop);
 869                 fw3_ipt_rule_addarg(r, false, "--datestop", buf);
 870         }
 871
 872         if (time->timestart)
 873         {
 874                 sprintf(buf, "%02d:%02d:%02d",
 875                         time->timestart / 3600,
 876                         time->timestart % 3600 / 60,
 877                         time->timestart % 60);
 878
 879                 fw3_ipt_rule_addarg(r, false, "--timestart", buf);
 880         }
 881
 882         if (time->timestop)
 883         {
 884                 sprintf(buf, "%02d:%02d:%02d",
 885                         time->timestop / 3600,
 886                         time->timestop % 3600 / 60,
 887                         time->timestop % 60);
 888
 889                 fw3_ipt_rule_addarg(r, false, "--timestop", buf);
 890         }
 891
 892         if (time->monthdays & 0xFFFFFFFE)
 893         {
 894                 for (i = 1, p = buf; i < 32; i++)
 895                 {
 896                         if (hasbit(time->monthdays, i))
 897                         {
 898                                 if (p > buf)
 899                                         *p++ = ',';
 900
 901                                 p += sprintf(p, "%u", i);
 902                         }
 903                 }
 904
 905                 fw3_ipt_rule_addarg(r, hasbit(time->monthdays, 0), "--monthdays", buf);
 906         }
 907
 908         if (time->weekdays & 0xFE)
 909         {
 910                 for (i = 1, p = buf; i < 8; i++)
 911                 {
 912                         if (hasbit(time->weekdays, i))
 913                         {
 914                                 if (p > buf)
 915                                         *p++ = ',';
 916
 917                                 p += sprintf(p, "%u", i);
 918                         }
 919                 }
 920
 921                 fw3_ipt_rule_addarg(r, hasbit(time->weekdays, 0), "--weekdays", buf);
 922         }
 923 }
 924
 925 void
 926 fw3_ipt_rule_mark(struct fw3_ipt_rule *r, struct fw3_mark *mark)
 927 {
 928         char buf[sizeof("0xFFFFFFFF/0xFFFFFFFF\0")];
 929
 930         if (!mark || !mark->set)
 931                 return;
 932
 933         if (mark->mask < 0xFFFFFFFF)
 934                 sprintf(buf, "0x%x/0x%x", mark->mark, mark->mask);
 935         else
 936                 sprintf(buf, "0x%x", mark->mark);
 937
 938         fw3_ipt_rule_addarg(r, false, "-m", "mark");
 939         fw3_ipt_rule_addarg(r, mark->invert, "--mark", buf);
 940 }
 941
 942 void
 943 fw3_ipt_rule_comment(struct fw3_ipt_rule *r, const char *fmt, ...)
 944 {
 945         va_list ap;
 946         char buf[256];
 947
 948         if (!fmt || !*fmt)
 949                 return;
 950
 951         va_start(ap, fmt);
 952         vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
 953         va_end(ap);
 954
 955         fw3_ipt_rule_addarg(r, false, "-m", "comment");
 956         fw3_ipt_rule_addarg(r, false, "--comment", buf);
 957 }
 958
 959 void
 960 fw3_ipt_rule_extra(struct fw3_ipt_rule *r, const char *extra)
 961 {
 962         char *p, **tmp, *s;
 963
 964         if (!extra || !*extra)
 965                 return;
 966
 967         s = fw3_strdup(extra);
 968
 969         for (p = strtok(s, " \t"); p; p = strtok(NULL, " \t"))
 970         {
 971                 tmp = realloc(r->argv, (r->argc + 1) * sizeof(*r->argv));
 972
 973                 if (!tmp)
 974                         break;
 975
 976                 r->argv = tmp;
 977                 r->argv[r->argc++] = fw3_strdup(p);
 978         }
 979
 980         free(s);
 981 }
 982
 983 #ifndef DISABLE_IPV6
 984 static void
 985 rule_print6(struct ip6t_entry *e)
 986 {
 987         char buf[INET6_ADDRSTRLEN];
 988         char *pname;
 989
 990         if (e->ipv6.flags & IP6T_F_PROTO)
 991         {
 992                 if (e->ipv6.flags & XT_INV_PROTO)
 993                         printf(" !");
 994
 995                 pname = get_protoname(container_of(e, struct fw3_ipt_rule, e6));
 996
 997                 if (pname)
 998                         printf(" -p %s", pname);
 999                 else
1000                         printf(" -p %u", e->ipv6.proto);
1001         }
1002
1003         if (e->ipv6.iniface[0])
1004         {
1005                 if (e->ipv6.flags & IP6T_INV_VIA_IN)
1006                         printf(" !");
1007
1008                 printf(" -i %s", e->ipv6.iniface);
1009         }
1010
1011         if (e->ipv6.outiface[0])
1012         {
1013                 if (e->ipv6.flags & IP6T_INV_VIA_OUT)
1014                         printf(" !");
1015
1016                 printf(" -o %s", e->ipv6.outiface);
1017         }
1018
1019         if (memcmp(&e->ipv6.src, &in6addr_any, sizeof(struct in6_addr)))
1020         {
1021                 if (e->ipv6.flags & IP6T_INV_SRCIP)
1022                         printf(" !");
1023
1024                 printf(" -s %s/%u", inet_ntop(AF_INET6, &e->ipv6.src, buf, sizeof(buf)),
1025                                     xtables_ip6mask_to_cidr(&e->ipv6.smsk));
1026         }
1027
1028         if (memcmp(&e->ipv6.dst, &in6addr_any, sizeof(struct in6_addr)))
1029         {
1030                 if (e->ipv6.flags & IP6T_INV_DSTIP)
1031                         printf(" !");
1032
1033                 printf(" -d %s/%u", inet_ntop(AF_INET6, &e->ipv6.dst, buf, sizeof(buf)),
1034                                     xtables_ip6mask_to_cidr(&e->ipv6.dmsk));
1035         }
1036 }
1037 #endif
1038
1039 static void
1040 rule_print4(struct ipt_entry *e)
1041 {
1042         struct in_addr in_zero = { 0 };
1043         char buf[sizeof("255.255.255.255\0")];
1044         char *pname;
1045
1046         if (e->ip.proto)
1047         {
1048                 if (e->ip.flags & XT_INV_PROTO)
1049                         printf(" !");
1050
1051                 pname = get_protoname(container_of(e, struct fw3_ipt_rule, e));
1052
1053                 if (pname)
1054                         printf(" -p %s", pname);
1055                 else
1056                         printf(" -p %u", e->ip.proto);
1057         }
1058
1059         if (e->ip.iniface[0])
1060         {
1061                 if (e->ip.flags & IPT_INV_VIA_IN)
1062                         printf(" !");
1063
1064                 printf(" -i %s", e->ip.iniface);
1065         }
1066
1067         if (e->ip.outiface[0])
1068         {
1069                 if (e->ip.flags & IPT_INV_VIA_OUT)
1070                         printf(" !");
1071
1072                 printf(" -o %s", e->ip.outiface);
1073         }
1074
1075         if (memcmp(&e->ip.src, &in_zero, sizeof(struct in_addr)))
1076         {
1077                 if (e->ip.flags & IPT_INV_SRCIP)
1078                         printf(" !");
1079
1080                 printf(" -s %s/%u", inet_ntop(AF_INET, &e->ip.src, buf, sizeof(buf)),
1081                                     xtables_ipmask_to_cidr(&e->ip.smsk));
1082         }
1083
1084         if (memcmp(&e->ip.dst, &in_zero, sizeof(struct in_addr)))
1085         {
1086                 if (e->ip.flags & IPT_INV_DSTIP)
1087                         printf(" !");
1088
1089                 printf(" -d %s/%u", inet_ntop(AF_INET, &e->ip.dst, buf, sizeof(buf)),
1090                                     xtables_ipmask_to_cidr(&e->ip.dmsk));
1091         }
1092 }
1093
1094 static void
1095 rule_print(struct fw3_ipt_rule *r, const char *prefix, const char *chain)
1096 {
1097         debug(r->h, "%s %s", prefix, chain);
1098
1099 #ifndef DISABLE_IPV6
1100         if (r->h->family == FW3_FAMILY_V6)
1101                 rule_print6(&r->e6);
1102         else
1103 #endif
1104                 rule_print4(&r->e);
1105
1106         fw3_xt_print_matches(&r->e.ip, r->matches);
1107         fw3_xt_print_target(&r->e.ip, r->target);
1108
1109         printf("\n");
1110 }
1111
1112 static bool
1113 parse_option(struct fw3_ipt_rule *r, int optc, bool inv)
1114 {
1115         struct xtables_rule_match *m;
1116         struct xtables_match *em;
1117
1118         /* is a target option */
1119         if (r->target && fw3_xt_has_target_parse(r->target) &&
1120                 optc >= r->target->option_offset &&
1121                 optc < (r->target->option_offset + 256))
1122         {
1123                 xtables_option_tpcall(optc, r->argv, inv, r->target, &r->e);
1124                 return false;
1125         }
1126
1127         /* try to dispatch argument to one of the match parsers */
1128         for (m = r->matches; m; m = m->next)
1129         {
1130                 em = m->match;
1131
1132                 if (m->completed || !fw3_xt_has_match_parse(em))
1133                         continue;
1134
1135                 if (optc < em->option_offset ||
1136                         optc >= (em->option_offset + 256))
1137                         continue;
1138
1139                 xtables_option_mpcall(optc, r->argv, inv, em, &r->e);
1140                 return false;
1141         }
1142
1143         /* unhandled option, might belong to a protocol match */
1144         if ((em = load_protomatch(r)) != NULL)
1145         {
1146                 init_match(r, em, false);
1147
1148                 r->protocol_loaded = true;
1149                 optind--;
1150
1151                 return true;
1152         }
1153
1154         if (optc == ':')
1155                 warn("parse_option(): option '%s' needs argument", r->argv[optind-1]);
1156
1157         if (optc == '?')
1158                 warn("parse_option(): unknown option '%s'", r->argv[optind-1]);
1159
1160         return false;
1161 }
1162
1163 void
1164 fw3_ipt_rule_addarg(struct fw3_ipt_rule *r, bool inv,
1165                     const char *k, const char *v)
1166 {
1167         int n;
1168         char **tmp;
1169
1170         if (!k)
1171                 return;
1172
1173         n = inv + !!k + !!v;
1174         tmp = realloc(r->argv, (r->argc + n) * sizeof(*tmp));
1175
1176         if (!tmp)
1177                 return;
1178
1179         r->argv = tmp;
1180
1181         if (inv)
1182                 r->argv[r->argc++] = fw3_strdup("!");
1183
1184         r->argv[r->argc++] = fw3_strdup(k);
1185
1186         if (v)
1187                 r->argv[r->argc++] = fw3_strdup(v);
1188 }
1189
1190 static unsigned char *
1191 rule_mask(struct fw3_ipt_rule *r)
1192 {
1193         size_t s;
1194         unsigned char *p, *mask = NULL;
1195         struct xtables_rule_match *m;
1196
1197 #define SZ(x) XT_ALIGN(sizeof(struct x))
1198
1199 #ifndef DISABLE_IPV6
1200         if (r->h->family == FW3_FAMILY_V6)
1201         {
1202                 s = SZ(ip6t_entry);
1203
1204                 for (m = r->matches; m; m = m->next)
1205                         s += SZ(ip6t_entry_match) + m->match->size;
1206
1207                 s += SZ(ip6t_entry_target) + r->target->size;
1208
1209                 mask = fw3_alloc(s);
1210                 memset(mask, 0xFF, SZ(ip6t_entry));
1211                 p = mask + SZ(ip6t_entry);
1212
1213                 for (m = r->matches; m; m = m->next)
1214                 {
1215                         memset(p, 0xFF, SZ(ip6t_entry_match) + m->match->userspacesize);
1216                         p += SZ(ip6t_entry_match) + m->match->size;
1217                 }
1218
1219                 memset(p, 0xFF, SZ(ip6t_entry_target) + r->target->userspacesize);
1220         }
1221         else
1222 #endif
1223         {
1224                 s = SZ(ipt_entry);
1225
1226                 for (m = r->matches; m; m = m->next)
1227                         s += SZ(ipt_entry_match) + m->match->size;
1228
1229                 s += SZ(ipt_entry_target) + r->target->size;
1230
1231                 mask = fw3_alloc(s);
1232                 memset(mask, 0xFF, SZ(ipt_entry));
1233                 p = mask + SZ(ipt_entry);
1234
1235                 for (m = r->matches; m; m = m->next)
1236                 {
1237                         memset(p, 0xFF, SZ(ipt_entry_match) + m->match->userspacesize);
1238                         p += SZ(ipt_entry_match) + m->match->size;
1239                 }
1240
1241                 memset(p, 0xFF, SZ(ipt_entry_target) + r->target->userspacesize);
1242         }
1243
1244         return mask;
1245 }
1246
1247 static void *
1248 rule_build(struct fw3_ipt_rule *r)
1249 {
1250         size_t s;
1251         struct xtables_rule_match *m;
1252
1253 #ifndef DISABLE_IPV6
1254         if (r->h->family == FW3_FAMILY_V6)
1255         {
1256                 struct ip6t_entry *e6;
1257
1258                 s = XT_ALIGN(sizeof(struct ip6t_entry));
1259
1260                 for (m = r->matches; m; m = m->next)
1261                         s += m->match->m->u.match_size;
1262
1263                 e6 = fw3_alloc(s + r->target->t->u.target_size);
1264
1265                 memcpy(e6, &r->e6, sizeof(struct ip6t_entry));
1266
1267                 e6->target_offset = s;
1268                 e6->next_offset = s + r->target->t->u.target_size;
1269
1270                 s = 0;
1271
1272                 for (m = r->matches; m; m = m->next)
1273                 {
1274                         memcpy(e6->elems + s, m->match->m, m->match->m->u.match_size);
1275                         s += m->match->m->u.match_size;
1276                 }
1277
1278                 memcpy(e6->elems + s, r->target->t, r->target->t->u.target_size);
1279
1280                 return e6;
1281         }
1282         else
1283 #endif
1284         {
1285                 struct ipt_entry *e;
1286
1287                 s = XT_ALIGN(sizeof(struct ipt_entry));
1288
1289                 for (m = r->matches; m; m = m->next)
1290                         s += m->match->m->u.match_size;
1291
1292                 e = fw3_alloc(s + r->target->t->u.target_size);
1293
1294                 memcpy(e, &r->e, sizeof(struct ipt_entry));
1295
1296                 e->target_offset = s;
1297                 e->next_offset = s + r->target->t->u.target_size;
1298
1299                 s = 0;
1300
1301                 for (m = r->matches; m; m = m->next)
1302                 {
1303                         memcpy(e->elems + s, m->match->m, m->match->m->u.match_size);
1304                         s += m->match->m->u.match_size;
1305                 }
1306
1307                 memcpy(e->elems + s, r->target->t, r->target->t->u.target_size);
1308
1309                 return e;
1310         }
1311 }
1312
1313 void
1314 __fw3_ipt_rule_append(struct fw3_ipt_rule *r, bool repl, const char *fmt, ...)
1315 {
1316         void *rule;
1317         unsigned char *mask;
1318
1319         struct xtables_rule_match *m;
1320         struct xtables_match *em;
1321         struct xtables_target *et;
1322         struct xtables_globals *g;
1323
1324         int i, optc;
1325         bool inv = false;
1326         char buf[32];
1327         va_list ap;
1328
1329         va_start(ap, fmt);
1330         vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
1331         va_end(ap);
1332
1333         g = (r->h->family == FW3_FAMILY_V6) ? &xtg6 : &xtg;
1334         g->opts = g->orig_opts;
1335
1336         optind = 0;
1337         opterr = 0;
1338
1339         while ((optc = getopt_long(r->argc, r->argv, "-:m:j:", g->opts,
1340                                    NULL)) != -1)
1341         {
1342                 switch (optc)
1343                 {
1344                 case 'm':
1345                         em = find_match(r, optarg);
1346
1347                         if (!em)
1348                         {
1349                                 warn("fw3_ipt_rule_append(): Can't find match '%s'", optarg);
1350                                 goto free;
1351                         }
1352
1353                         init_match(r, em, true);
1354                         break;
1355
1356                 case 'j':
1357                         et = get_target(r, optarg);
1358
1359                         if (!et)
1360                         {
1361                                 warn("fw3_ipt_rule_append(): Can't find target '%s'", optarg);
1362                                 goto free;
1363                         }
1364
1365                         break;
1366
1367                 case 1:
1368                         if ((optarg[0] == '!') && (optarg[1] == '\0'))
1369                         {
1370                                 optarg[0] = '\0';
1371                                 inv = true;
1372                                 continue;
1373                         }
1374
1375                         warn("fw3_ipt_rule_append(): Bad argument '%s'", optarg);
1376                         goto free;
1377
1378                 default:
1379                         if (parse_option(r, optc, inv))
1380                                 continue;
1381                         break;
1382                 }
1383
1384                 inv = false;
1385         }
1386
1387         for (m = r->matches; m; m = m->next)
1388                 xtables_option_mfcall(m->match);
1389
1390         if (r->target)
1391                 xtables_option_tfcall(r->target);
1392
1393         rule = rule_build(r);
1394
1395 #ifndef DISABLE_IPV6
1396         if (r->h->family == FW3_FAMILY_V6)
1397         {
1398                 if (repl)
1399                 {
1400                         mask = rule_mask(r);
1401
1402                         while (ip6tc_delete_entry(buf, rule, mask, r->h->handle))
1403                                 if (fw3_pr_debug)
1404                                         rule_print(r, "-D", buf);
1405
1406                         free(mask);
1407                 }
1408
1409                 if (fw3_pr_debug)
1410                         rule_print(r, "-A", buf);
1411
1412                 if (!ip6tc_append_entry(buf, rule, r->h->handle))
1413                         warn("ip6tc_append_entry(): %s", ip6tc_strerror(errno));
1414         }
1415         else
1416 #endif
1417         {
1418                 if (repl)
1419                 {
1420                         mask = rule_mask(r);
1421
1422                         while (iptc_delete_entry(buf, rule, mask, r->h->handle))
1423                                 if (fw3_pr_debug)
1424                                         rule_print(r, "-D", buf);
1425
1426                         free(mask);
1427                 }
1428
1429                 if (fw3_pr_debug)
1430                         rule_print(r, "-A", buf);
1431
1432                 if (!iptc_append_entry(buf, rule, r->h->handle))
1433                         warn("iptc_append_entry(): %s\n", iptc_strerror(errno));
1434         }
1435
1436         free(rule);
1437
1438 free:
1439         for (i = 1; i < r->argc; i++)
1440                 free(r->argv[i]);
1441
1442         free(r->argv);
1443
1444         xtables_rule_matches_free(&r->matches);
1445
1446         if (r->target)
1447                 free(r->target->t);
1448
1449         free(r);
1450
1451         /* reset all targets and matches */
1452         for (em = xtables_matches; em; em = em->next)
1453                 em->mflags = 0;
1454
1455         for (et = xtables_targets; et; et = et->next)
1456         {
1457                 et->tflags = 0;
1458                 et->used = 0;
1459         }
1460
1461         xtables_free_opts(1);
1462 }
1463
1464 struct fw3_ipt_rule *
1465 fw3_ipt_rule_create(struct fw3_ipt_handle *handle, struct fw3_protocol *proto,
1466                     struct fw3_device *in, struct fw3_device *out,
1467                     struct fw3_address *src, struct fw3_address *dest)
1468 {
1469         struct fw3_ipt_rule *r;
1470
1471         r = fw3_ipt_rule_new(handle);
1472
1473         fw3_ipt_rule_proto(r, proto);
1474         fw3_ipt_rule_in_out(r, in, out);
1475         fw3_ipt_rule_src_dest(r, src, dest);
1476
1477         return r;
1478 }