utils.c

   1 /*
   2  * firewall3 - 3rd OpenWrt UCI firewall implementation
   3  *
   4  *   Copyright (C) 2013 Jo-Philipp Wich <jo@mein.io>
   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 #define _GNU_SOURCE
  20
  21 #include <net/if.h>
  22 #include <sys/ioctl.h>
  23
  24 #include "utils.h"
  25 #include "options.h"
  26
  27 #include "zones.h"
  28 #include "ipsets.h"
  29
  30
  31 static int fw3_lock_fd = -1;
  32 static pid_t pipe_pid = -1;
  33 static FILE *pipe_fd = NULL;
  34
  35 bool fw3_pr_debug = false;
  36
  37
  38 static void
  39 warn_elem_section_name(struct uci_section *s, bool find_name)
  40 {
  41         int i = 0;
  42         struct uci_option *o;
  43         struct uci_element *tmp;
  44
  45         if (s->anonymous)
  46         {
  47                 uci_foreach_element(&s->package->sections, tmp)
  48                 {
  49                         if (strcmp(uci_to_section(tmp)->type, s->type))
  50                                 continue;
  51
  52                         if (&s->e == tmp)
  53                                 break;
  54
  55                         i++;
  56                 }
  57
  58                 fprintf(stderr, "@%s[%d]", s->type, i);
  59
  60                 if (find_name)
  61                 {
  62                         uci_foreach_element(&s->options, tmp)
  63                         {
  64                                 o = uci_to_option(tmp);
  65
  66                                 if (!strcmp(tmp->name, "name") && (o->type == UCI_TYPE_STRING))
  67                                 {
  68                                         fprintf(stderr, " (%s)", o->v.string);
  69                                         break;
  70                                 }
  71                         }
  72                 }
  73         }
  74         else
  75         {
  76                 fprintf(stderr, "'%s'", s->e.name);
  77         }
  78
  79         if (find_name)
  80                 fprintf(stderr, " ");
  81 }
  82
  83 void
  84 warn_elem(struct uci_element *e, const char *format, ...)
  85 {
  86         if (e->type == UCI_TYPE_SECTION)
  87         {
  88                 fprintf(stderr, "Warning: Section ");
  89                 warn_elem_section_name(uci_to_section(e), true);
  90         }
  91         else if (e->type == UCI_TYPE_OPTION)
  92         {
  93                 fprintf(stderr, "Warning: Option ");
  94                 warn_elem_section_name(uci_to_option(e)->section, false);
  95                 fprintf(stderr, ".%s ", e->name);
  96         }
  97
  98     va_list argptr;
  99     va_start(argptr, format);
 100     vfprintf(stderr, format, argptr);
 101     va_end(argptr);
 102
 103         fprintf(stderr, "\n");
 104 }
 105
 106 void
 107 warn(const char* format, ...)
 108 {
 109         fprintf(stderr, "Warning: ");
 110     va_list argptr;
 111     va_start(argptr, format);
 112     vfprintf(stderr, format, argptr);
 113     va_end(argptr);
 114         fprintf(stderr, "\n");
 115 }
 116
 117 void
 118 error(const char* format, ...)
 119 {
 120         fprintf(stderr, "Error: ");
 121     va_list argptr;
 122     va_start(argptr, format);
 123     vfprintf(stderr, format, argptr);
 124     va_end(argptr);
 125         fprintf(stderr, "\n");
 126
 127         exit(1);
 128 }
 129
 130 void
 131 info(const char* format, ...)
 132 {
 133         va_list argptr;
 134     va_start(argptr, format);
 135     vfprintf(stderr, format, argptr);
 136     va_end(argptr);
 137         fprintf(stderr, "\n");
 138 }
 139
 140 void *
 141 fw3_alloc(size_t size)
 142 {
 143         void *mem;
 144
 145         mem = calloc(1, size);
 146
 147         if (!mem)
 148                 error("Out of memory while allocating %zd bytes", size);
 149
 150         return mem;
 151 }
 152
 153 char *
 154 fw3_strdup(const char *s)
 155 {
 156         char *ns;
 157
 158         ns = strdup(s);
 159
 160         if (!ns)
 161                 error("Out of memory while duplicating string '%s'", s);
 162
 163         return ns;
 164 }
 165
 166 const char *
 167 fw3_find_command(const char *cmd)
 168 {
 169         struct stat s;
 170         int plen = 0, clen = strlen(cmd) + 1;
 171         char *search, *p;
 172         static char path[PATH_MAX];
 173
 174         if (!stat(cmd, &s) && S_ISREG(s.st_mode))
 175                 return cmd;
 176
 177         search = getenv("PATH");
 178
 179         if (!search)
 180                 search = "/bin:/usr/bin:/sbin:/usr/sbin";
 181
 182         p = search;
 183
 184         do
 185         {
 186                 if (*p != ':' && *p != '\0')
 187                         continue;
 188
 189                 plen = p - search;
 190
 191                 if ((plen + clen) >= sizeof(path))
 192                         continue;
 193
 194                 snprintf(path, sizeof(path), "%.*s/%s", plen, search, cmd);
 195
 196                 if (!stat(path, &s) && S_ISREG(s.st_mode))
 197                         return path;
 198
 199                 search = p + 1;
 200         }
 201         while (*p++);
 202
 203         return NULL;
 204 }
 205
 206 bool
 207 fw3_stdout_pipe(void)
 208 {
 209         pipe_fd = stdout;
 210         return true;
 211 }
 212
 213 bool
 214 __fw3_command_pipe(bool silent, const char *command, ...)
 215 {
 216         pid_t pid;
 217         va_list argp;
 218         int pfds[2];
 219         int argn;
 220         char *arg, **args, **tmp;
 221
 222         command = fw3_find_command(command);
 223
 224         if (!command)
 225                 return false;
 226
 227         if (pipe(pfds))
 228                 return false;
 229
 230         argn = 2;
 231         args = calloc(argn, sizeof(arg));
 232
 233         if (!args)
 234                 return false;
 235
 236         args[0] = (char *)command;
 237         args[1] = NULL;
 238
 239         va_start(argp, command);
 240
 241         while ((arg = va_arg(argp, char *)) != NULL)
 242         {
 243                 tmp = realloc(args, ++argn * sizeof(arg));
 244
 245                 if (!tmp)
 246                         break;
 247
 248                 args = tmp;
 249                 args[argn-2] = arg;
 250                 args[argn-1] = NULL;
 251         }
 252
 253         va_end(argp);
 254
 255         switch ((pid = fork()))
 256         {
 257         case -1:
 258                 free(args);
 259                 return false;
 260
 261         case 0:
 262                 dup2(pfds[0], 0);
 263
 264                 close(pfds[0]);
 265                 close(pfds[1]);
 266
 267                 close(1);
 268
 269                 if (silent)
 270                         close(2);
 271
 272                 execv(command, args);
 273
 274         default:
 275                 signal(SIGPIPE, SIG_IGN);
 276                 pipe_pid = pid;
 277                 close(pfds[0]);
 278                 fcntl(pfds[1], F_SETFD, fcntl(pfds[1], F_GETFD) | FD_CLOEXEC);
 279         }
 280
 281         pipe_fd = fdopen(pfds[1], "w");
 282         free(args);
 283         return true;
 284 }
 285
 286 void
 287 fw3_pr(const char *fmt, ...)
 288 {
 289         va_list args;
 290
 291         if (fw3_pr_debug && pipe_fd != stdout)
 292         {
 293                 va_start(args, fmt);
 294                 vfprintf(stderr, fmt, args);
 295                 va_end(args);
 296         }
 297
 298         va_start(args, fmt);
 299         vfprintf(pipe_fd, fmt, args);
 300         va_end(args);
 301 }
 302
 303 void
 304 fw3_command_close(void)
 305 {
 306         if (pipe_fd && pipe_fd != stdout)
 307                 fclose(pipe_fd);
 308
 309         if (pipe_pid > -1)
 310                 waitpid(pipe_pid, NULL, 0);
 311
 312         signal(SIGPIPE, SIG_DFL);
 313
 314         pipe_fd = NULL;
 315         pipe_pid = -1;
 316 }
 317
 318 bool
 319 fw3_has_table(bool ipv6, const char *table)
 320 {
 321         FILE *f;
 322
 323         char line[12];
 324         bool seen = false;
 325
 326         const char *path = ipv6
 327                 ? "/proc/net/ip6_tables_names" : "/proc/net/ip_tables_names";
 328
 329         if (!(f = fopen(path, "r")))
 330                 return false;
 331
 332         while (fgets(line, sizeof(line), f))
 333         {
 334                 if (!strncmp(line, table, strlen(table)))
 335                 {
 336                         seen = true;
 337                         break;
 338                 }
 339         }
 340
 341         fclose(f);
 342
 343         return seen;
 344 }
 345
 346 bool
 347 fw3_has_target(const bool ipv6, const char *target)
 348 {
 349         FILE *f;
 350
 351         char line[12];
 352         bool seen = false;
 353
 354         const char *path = ipv6
 355                 ? "/proc/net/ip6_tables_targets" : "/proc/net/ip_tables_targets";
 356
 357         if (!(f = fopen(path, "r")))
 358                 return false;
 359
 360         while (fgets(line, sizeof(line), f))
 361         {
 362                 if (!strcmp(line, target))
 363                 {
 364                         seen = true;
 365                         break;
 366                 }
 367         }
 368
 369         fclose(f);
 370
 371         return seen;
 372 }
 373
 374 bool
 375 fw3_lock_path(int *fd, const char *path)
 376 {
 377         int lock_fd = open(path, O_CREAT|O_WRONLY, S_IRUSR|S_IWUSR);
 378
 379         if (lock_fd < 0)
 380         {
 381                 warn("Cannot create lock file %s: %s", path, strerror(errno));
 382                 return false;
 383         }
 384
 385         if (flock(lock_fd, LOCK_EX))
 386         {
 387                 warn("Cannot acquire exclusive lock: %s", strerror(errno));
 388                 close(lock_fd);
 389                 return false;
 390         }
 391
 392         *fd = lock_fd;
 393
 394         return true;
 395 }
 396
 397 bool
 398 fw3_lock()
 399 {
 400         return fw3_lock_path(&fw3_lock_fd, FW3_LOCKFILE);
 401 }
 402
 403
 404 void
 405 fw3_unlock_path(int *fd, const char *lockpath)
 406 {
 407         if (*fd < 0)
 408                 return;
 409
 410         if (flock(*fd, LOCK_UN))
 411                 warn("Cannot release exclusive lock: %s", strerror(errno));
 412
 413         close(*fd);
 414         unlink(FW3_LOCKFILE);
 415
 416         *fd = -1;
 417 }
 418
 419
 420 void
 421 fw3_unlock(void)
 422 {
 423         fw3_unlock_path(&fw3_lock_fd, FW3_LOCKFILE);
 424 }
 425
 426
 427 static void
 428 write_defaults_uci(struct uci_context *ctx, struct fw3_defaults *d,
 429                    struct uci_package *dest)
 430 {
 431         char buf[sizeof("0xffffffff")];
 432         struct uci_ptr ptr = { .p = dest };
 433
 434         uci_add_section(ctx, dest, "defaults", &ptr.s);
 435
 436         ptr.o      = NULL;
 437         ptr.option = "input";
 438         ptr.value  = fw3_flag_names[d->policy_input];
 439         uci_set(ctx, &ptr);
 440
 441         ptr.o      = NULL;
 442         ptr.option = "output";
 443         ptr.value  = fw3_flag_names[d->policy_output];
 444         uci_set(ctx, &ptr);
 445
 446         ptr.o      = NULL;
 447         ptr.option = "forward";
 448         ptr.value  = fw3_flag_names[d->policy_forward];
 449         uci_set(ctx, &ptr);
 450
 451         snprintf(buf, sizeof(buf), "0x%x", d->flags[0]);
 452         ptr.o      = NULL;
 453         ptr.option = "__flags_v4";
 454         ptr.value  = buf;
 455         uci_set(ctx, &ptr);
 456
 457         snprintf(buf, sizeof(buf), "0x%x", d->flags[1]);
 458         ptr.o      = NULL;
 459         ptr.option = "__flags_v6";
 460         ptr.value  = buf;
 461         uci_set(ctx, &ptr);
 462 }
 463
 464 static void
 465 write_zone_uci(struct uci_context *ctx, struct fw3_zone *z,
 466                struct uci_package *dest, struct ifaddrs *ifaddr)
 467 {
 468         struct fw3_device *dev;
 469         struct fw3_address *sub;
 470         struct ifaddrs *ifa;
 471         enum fw3_family fam = FW3_FAMILY_ANY;
 472
 473         char *p, buf[INET6_ADDRSTRLEN];
 474
 475         struct uci_ptr ptr = { .p = dest };
 476
 477         if (!z->enabled)
 478                 return;
 479
 480         if (fw3_no_table(z->flags[0]) && !fw3_no_table(z->flags[1]))
 481                 fam = FW3_FAMILY_V6;
 482         else if (!fw3_no_table(z->flags[0]) && fw3_no_table(z->flags[1]))
 483                 fam = FW3_FAMILY_V4;
 484         else if (fw3_no_table(z->flags[0]) && fw3_no_table(z->flags[1]))
 485                 return;
 486
 487         uci_add_section(ctx, dest, "zone", &ptr.s);
 488
 489         ptr.o      = NULL;
 490         ptr.option = "name";
 491         ptr.value  = z->name;
 492         uci_set(ctx, &ptr);
 493
 494         ptr.o      = NULL;
 495         ptr.option = "input";
 496         ptr.value  = fw3_flag_names[z->policy_input];
 497         uci_set(ctx, &ptr);
 498
 499         ptr.o      = NULL;
 500         ptr.option = "output";
 501         ptr.value  = fw3_flag_names[z->policy_output];
 502         uci_set(ctx, &ptr);
 503
 504         ptr.o      = NULL;
 505         ptr.option = "forward";
 506         ptr.value  = fw3_flag_names[z->policy_forward];
 507         uci_set(ctx, &ptr);
 508
 509         ptr.o      = NULL;
 510         ptr.option = "masq";
 511         ptr.value  = z->masq ? "1" : "0";
 512         uci_set(ctx, &ptr);
 513
 514         ptr.o      = NULL;
 515         ptr.option = "mtu_fix";
 516         ptr.value  = z->mtu_fix ? "1" : "0";
 517         uci_set(ctx, &ptr);
 518
 519         ptr.o      = NULL;
 520         ptr.option = "custom_chains";
 521         ptr.value  = z->custom_chains ? "1" : "0";
 522         uci_set(ctx, &ptr);
 523
 524         if (fam != FW3_FAMILY_ANY)
 525         {
 526                 ptr.o      = NULL;
 527                 ptr.option = "family";
 528                 ptr.value  = fw3_flag_names[fam];
 529                 uci_set(ctx, &ptr);
 530         }
 531
 532         ptr.o      = NULL;
 533         ptr.option = "device";
 534
 535         fw3_foreach(dev, &z->devices)
 536         {
 537                 char *ep;
 538
 539                 if (!dev)
 540                         continue;
 541
 542                 p = buf;
 543                 ep = buf + sizeof(buf);
 544
 545                 if (dev->invert)
 546                         p += snprintf(p, ep - p, "!");
 547
 548                 if (*dev->network)
 549                         p += snprintf(p, ep - p, "%s@%s", dev->name, dev->network);
 550                 else
 551                         p += snprintf(p, ep - p, "%s", dev->name);
 552
 553                 ptr.value = buf;
 554                 uci_add_list(ctx, &ptr);
 555         }
 556
 557         ptr.o      = NULL;
 558         ptr.option = "subnet";
 559
 560         fw3_foreach(sub, &z->subnets)
 561         {
 562                 if (!sub)
 563                         continue;
 564
 565                 ptr.value = fw3_address_to_string(sub, true, false);
 566                 uci_add_list(ctx, &ptr);
 567         }
 568
 569         ptr.o      = NULL;
 570         ptr.option = "__addrs";
 571
 572         fw3_foreach(dev, &z->devices)
 573         {
 574                 if (!dev)
 575                         continue;
 576
 577                 for (ifa = ifaddr; ifa; ifa = ifa->ifa_next)
 578                 {
 579                         if (!ifa->ifa_addr || strcmp(dev->name, ifa->ifa_name))
 580                                 continue;
 581
 582                         if (ifa->ifa_addr->sa_family == AF_INET)
 583                                 inet_ntop(AF_INET,
 584                                           &((struct sockaddr_in *)ifa->ifa_addr)->sin_addr,
 585                                           buf, sizeof(buf));
 586                         else if (ifa->ifa_addr->sa_family == AF_INET6)
 587                                 inet_ntop(AF_INET6,
 588                                           &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr,
 589                                           buf, sizeof(buf));
 590                         else
 591                                 continue;
 592
 593                         ptr.value = buf;
 594                         uci_add_list(ctx, &ptr);
 595                 }
 596         }
 597
 598         if (z->extra_src)
 599         {
 600                 ptr.o      = NULL;
 601                 ptr.option = "extra_src";
 602                 ptr.value  = z->extra_src;
 603                 uci_set(ctx, &ptr);
 604         }
 605
 606         if (z->extra_dest)
 607         {
 608                 ptr.o      = NULL;
 609                 ptr.option = "extra_dest";
 610                 ptr.value  = z->extra_dest;
 611                 uci_set(ctx, &ptr);
 612         }
 613
 614         snprintf(buf, sizeof(buf), "0x%x", z->flags[0]);
 615         ptr.o      = NULL;
 616         ptr.option = "__flags_v4";
 617         ptr.value  = buf;
 618         uci_set(ctx, &ptr);
 619
 620         snprintf(buf, sizeof(buf), "0x%x", z->flags[1]);
 621         ptr.o      = NULL;
 622         ptr.option = "__flags_v6";
 623         ptr.value  = buf;
 624         uci_set(ctx, &ptr);
 625 }
 626
 627 static void
 628 write_ipset_uci(struct uci_context *ctx, struct fw3_ipset *s,
 629                 struct uci_package *dest)
 630 {
 631         struct fw3_ipset_datatype *type;
 632
 633         char buf[sizeof("65535-65535")];
 634
 635         struct uci_ptr ptr = { .p = dest };
 636
 637         if (!s->enabled || s->external)
 638                 return;
 639
 640         uci_add_section(ctx, dest, "ipset", &ptr.s);
 641
 642         ptr.o      = NULL;
 643         ptr.option = "name";
 644         ptr.value  = s->name;
 645         uci_set(ctx, &ptr);
 646
 647         ptr.o      = NULL;
 648         ptr.option = "family";
 649         if (s->family == FW3_FAMILY_V4)
 650                 ptr.value = "ipv4";
 651         else
 652                 ptr.value = "ipv6";
 653         uci_set(ctx, &ptr);
 654
 655         ptr.o      = NULL;
 656         ptr.option = "storage";
 657         ptr.value  = fw3_ipset_method_names[s->method];
 658         uci_set(ctx, &ptr);
 659
 660         list_for_each_entry(type, &s->datatypes, list)
 661         {
 662                 snprintf(buf, sizeof(buf), "%s_%s", type->dir, fw3_ipset_type_names[type->type]);
 663                 ptr.o      = NULL;
 664                 ptr.option = "match";
 665                 ptr.value  = buf;
 666                 uci_add_list(ctx, &ptr);
 667         }
 668
 669         if (s->iprange.set)
 670         {
 671                 ptr.o      = NULL;
 672                 ptr.option = "iprange";
 673                 ptr.value  = fw3_address_to_string(&s->iprange, false, false);
 674                 uci_set(ctx, &ptr);
 675         }
 676
 677         if (s->portrange.set)
 678         {
 679                 snprintf(buf, sizeof(buf), "%u-%u", s->portrange.port_min, s->portrange.port_max);
 680                 ptr.o      = NULL;
 681                 ptr.option = "portrange";
 682                 ptr.value  = buf;
 683                 uci_set(ctx, &ptr);
 684         }
 685 }
 686
 687 void
 688 fw3_write_statefile(void *state)
 689 {
 690         FILE *sf;
 691         struct fw3_state *s = state;
 692         struct fw3_zone *z;
 693         struct fw3_ipset *i;
 694         struct ifaddrs *ifaddr;
 695
 696         struct uci_package *p;
 697
 698         if (fw3_no_family(s->defaults.flags[0]) &&
 699             fw3_no_family(s->defaults.flags[1]))
 700         {
 701                 unlink(FW3_STATEFILE);
 702         }
 703         else
 704         {
 705                 sf = fopen(FW3_STATEFILE, "w+");
 706
 707                 if (!sf)
 708                 {
 709                         warn("Cannot create state %s: %s", FW3_STATEFILE, strerror(errno));
 710                         return;
 711                 }
 712
 713                 if (getifaddrs(&ifaddr))
 714                 {
 715                         warn("Cannot get interface addresses: %s", strerror(errno));
 716                         ifaddr = NULL;
 717                 }
 718
 719                 if ((p = uci_lookup_package(s->uci, "fw3_state")) != NULL)
 720                         uci_unload(s->uci, p);
 721
 722                 uci_import(s->uci, sf, "fw3_state", NULL, true);
 723
 724                 if ((p = uci_lookup_package(s->uci, "fw3_state")) != NULL)
 725                 {
 726                         write_defaults_uci(s->uci, &s->defaults, p);
 727
 728                         list_for_each_entry(z, &s->zones, list)
 729                                 write_zone_uci(s->uci, z, p, ifaddr);
 730
 731                         list_for_each_entry(i, &s->ipsets, list)
 732                                 write_ipset_uci(s->uci, i, p);
 733
 734                         uci_export(s->uci, sf, p, true);
 735                         uci_unload(s->uci, p);
 736                 }
 737
 738                 fsync(fileno(sf));
 739                 fclose(sf);
 740
 741                 if (ifaddr)
 742                         freeifaddrs(ifaddr);
 743         }
 744 }
 745
 746
 747 void
 748 fw3_free_object(void *obj, const void *opts)
 749 {
 750         const struct fw3_option *ol;
 751         struct list_head *list, *cur, *tmp;
 752
 753         for (ol = opts; ol->name; ol++)
 754         {
 755                 if (!ol->elem_size)
 756                         continue;
 757
 758                 list = (struct list_head *)((char *)obj + ol->offset);
 759                 list_for_each_safe(cur, tmp, list)
 760                 {
 761                         list_del(cur);
 762                         free(cur);
 763                 }
 764         }
 765
 766         free(obj);
 767 }
 768
 769 void
 770 fw3_free_list(struct list_head *head)
 771 {
 772         struct list_head *entry, *tmp;
 773
 774         if (!head)
 775                 return;
 776
 777         list_for_each_safe(entry, tmp, head)
 778         {
 779                 list_del(entry);
 780                 free(entry);
 781         }
 782
 783         free(head);
 784 }
 785
 786 bool
 787 fw3_hotplug(bool add, void *zone, void *device)
 788 {
 789         struct fw3_zone *z = zone;
 790         struct fw3_device *d = device;
 791
 792         if (!*d->network)
 793                 return false;
 794
 795         switch (fork())
 796         {
 797         case -1:
 798                 warn("Unable to fork(): %s\n", strerror(errno));
 799                 return false;
 800
 801         case 0:
 802                 break;
 803
 804         default:
 805                 return true;
 806         }
 807
 808         close(0);
 809         close(1);
 810         close(2);
 811         if (chdir("/")) {};
 812
 813         clearenv();
 814         setenv("ACTION",    add ? "add" : "remove", 1);
 815         setenv("ZONE",      z->name,                1);
 816         setenv("INTERFACE", d->network,             1);
 817         setenv("DEVICE",    d->name,                1);
 818
 819         execl(FW3_HOTPLUG, FW3_HOTPLUG, "firewall", NULL);
 820
 821         /* unreached */
 822         return false;
 823 }
 824
 825 int
 826 fw3_netmask2bitlen(int family, void *mask)
 827 {
 828         int bits;
 829         struct in_addr *v4;
 830         struct in6_addr *v6;
 831
 832         if (family == FW3_FAMILY_V6)
 833                 for (bits = 0, v6 = mask;
 834                      bits < 128 && (v6->s6_addr[bits / 8] << (bits % 8)) & 128;
 835                      bits++);
 836         else
 837                 for (bits = 0, v4 = mask;
 838                      bits < 32 && (ntohl(v4->s_addr) << bits) & 0x80000000;
 839                      bits++);
 840
 841         return bits;
 842 }
 843
 844 bool
 845 fw3_bitlen2netmask(int family, int bits, void *mask)
 846 {
 847         int i;
 848         uint8_t rem, b;
 849         struct in_addr *v4;
 850         struct in6_addr *v6;
 851
 852         if (family == FW3_FAMILY_V6)
 853         {
 854                 if (bits < -128 || bits > 128)
 855                         return false;
 856
 857                 v6 = mask;
 858                 rem = abs(bits);
 859
 860                 for (i = 0; i < sizeof(v6->s6_addr); i++)
 861                 {
 862                         b = (rem > 8) ? 8 : rem;
 863                         v6->s6_addr[i] = (uint8_t)(0xFF << (8 - b));
 864                         rem -= b;
 865                 }
 866
 867                 if (bits < 0)
 868                         for (i = 0; i < sizeof(v6->s6_addr); i++)
 869                                 v6->s6_addr[i] = ~v6->s6_addr[i];
 870         }
 871         else
 872         {
 873                 if (bits < -32 || bits > 32)
 874                         return false;
 875
 876                 v4 = mask;
 877                 v4->s_addr = bits ? htonl(~((1 << (32 - abs(bits))) - 1)) : 0;
 878
 879                 if (bits < 0)
 880                         v4->s_addr = ~v4->s_addr;
 881         }
 882
 883         return true;
 884 }
 885
 886 void
 887 fw3_flush_conntrack(void *state)
 888 {
 889         bool found;
 890         struct fw3_state *s = state;
 891         struct fw3_address *addr;
 892         struct fw3_device *dev;
 893         struct fw3_zone *zone;
 894         struct ifaddrs *ifaddr, *ifa;
 895         struct sockaddr_in *sin;
 896         struct sockaddr_in6 *sin6;
 897         char buf[INET6_ADDRSTRLEN];
 898         FILE *ct;
 899
 900         if (!state)
 901         {
 902                 if ((ct = fopen("/proc/net/nf_conntrack", "w")) != NULL)
 903                 {
 904                         info(" * Flushing conntrack table ...");
 905
 906                         fwrite("f\n", 1, 2, ct);
 907                         fclose(ct);
 908                 }
 909
 910                 return;
 911         }
 912
 913         if (getifaddrs(&ifaddr))
 914         {
 915                 warn("Cannot get interface addresses: %s", strerror(errno));
 916                 return;
 917         }
 918
 919         if ((ct = fopen("/proc/net/nf_conntrack", "w")) != NULL)
 920         {
 921                 list_for_each_entry(zone, &s->zones, list)
 922                 list_for_each_entry(addr, &zone->old_addrs, list)
 923                 {
 924                         found = false;
 925
 926                         list_for_each_entry(dev, &zone->devices, list)
 927                         {
 928                                 for (ifa = ifaddr; ifa && !found; ifa = ifa->ifa_next)
 929                                 {
 930                                         if (!ifa->ifa_addr || strcmp(dev->name, ifa->ifa_name))
 931                                                 continue;
 932
 933                                         sin = (struct sockaddr_in *)ifa->ifa_addr;
 934                                         sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
 935
 936                                         if (addr->family == FW3_FAMILY_V4 &&
 937                                                 sin->sin_family == AF_INET)
 938                                         {
 939                                                 found = !memcmp(&addr->address.v4, &sin->sin_addr,
 940                                                                                 sizeof(sin->sin_addr));
 941                                         }
 942                                         else if (addr->family == FW3_FAMILY_V6 &&
 943                                                          sin6->sin6_family == AF_INET6)
 944                                         {
 945                                                 found = !memcmp(&addr->address.v6, &sin6->sin6_addr,
 946                                                                                 sizeof(sin6->sin6_addr));
 947                                         }
 948                                 }
 949
 950                                 if (found)
 951                                         break;
 952                         }
 953
 954                         if (!found)
 955                         {
 956                                 inet_ntop(addr->family == FW3_FAMILY_V4 ? AF_INET : AF_INET6,
 957                                                   &addr->address.v4, buf, sizeof(buf));
 958
 959                                 info(" * Flushing conntrack: %s", buf);
 960                                 fprintf(ct, "%s\n", buf);
 961                         }
 962                 }
 963
 964                 fclose(ct);
 965         }
 966
 967         freeifaddrs(ifaddr);
 968 }
 969
 970 bool fw3_attr_parse_name_type(struct blob_attr *entry, const char **name, const char **type)
 971 {
 972         struct blob_attr *opt;
 973         unsigned orem;
 974
 975         if (!type || !name)
 976                 return false;
 977
 978         *type = NULL;
 979
 980         blobmsg_for_each_attr(opt, entry, orem)
 981                 if (!strcmp(blobmsg_name(opt), "type"))
 982                         *type = blobmsg_get_string(opt);
 983                 else if (!strcmp(blobmsg_name(opt), "name"))
 984                         *name = blobmsg_get_string(opt);
 985
 986         return *type != NULL ? true : false;
 987 }
 988
 989 const char *
 990 fw3_protoname(void *proto)
 991 {
 992         static char buf[sizeof("4294967295")];
 993         struct fw3_protocol *p = proto;
 994         struct protoent *pe;
 995
 996         if (!p)
 997                 return "?";
 998
 999         pe = getprotobynumber(p->protocol);
1000
1001         if (!pe)
1002         {
1003                 snprintf(buf, sizeof(buf), "%u", p->protocol);
1004                 return buf;
1005         }
1006
1007         return pe->p_name;
1008 }
1009
1010 bool
1011 fw3_check_loopback_dev(const char *name)
1012 {
1013         struct ifreq ifr;
1014         int s;
1015         bool rv = false;
1016
1017         s = socket(AF_LOCAL, SOCK_DGRAM, 0);
1018
1019         if (s < 0)
1020                 return false;
1021
1022         memset(&ifr, 0, sizeof(ifr));
1023         snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s", name);
1024
1025         if (ioctl(s, SIOCGIFFLAGS, &ifr) >= 0) {
1026                 if (ifr.ifr_flags & IFF_LOOPBACK)
1027                         rv = true;
1028         }
1029
1030         close(s);
1031
1032         return rv;
1033 }
1034
1035 bool
1036 fw3_check_loopback_addr(struct fw3_address *addr)
1037 {
1038         if (addr->family == FW3_FAMILY_V4 &&
1039             (ntohl(addr->address.v4.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET)
1040                 return true;
1041
1042         if (addr->family == FW3_FAMILY_V6 && !addr->range &&
1043             fw3_netmask2bitlen(FW3_FAMILY_V6, &addr->mask.v6) == 128 &&
1044             IN6_IS_ADDR_LOOPBACK(&addr->address.v6))
1045                 return true;
1046
1047         return false;
1048 }