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 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 %d 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                 strncpy(path, search, plen);
 195                 sprintf(path + plen, "/%s", cmd);
 196
 197                 if (!stat(path, &s) && S_ISREG(s.st_mode))
 198                         return path;
 199
 200                 search = p + 1;
 201         }
 202         while (*p++);
 203
 204         return NULL;
 205 }
 206
 207 bool
 208 fw3_stdout_pipe(void)
 209 {
 210         pipe_fd = stdout;
 211         return true;
 212 }
 213
 214 bool
 215 __fw3_command_pipe(bool silent, const char *command, ...)
 216 {
 217         pid_t pid;
 218         va_list argp;
 219         int pfds[2];
 220         int argn;
 221         char *arg, **args, **tmp;
 222
 223         command = fw3_find_command(command);
 224
 225         if (!command)
 226                 return false;
 227
 228         if (pipe(pfds))
 229                 return false;
 230
 231         argn = 2;
 232         args = calloc(argn, sizeof(arg));
 233
 234         if (!args)
 235                 return false;
 236
 237         args[0] = (char *)command;
 238         args[1] = NULL;
 239
 240         va_start(argp, command);
 241
 242         while ((arg = va_arg(argp, char *)) != NULL)
 243         {
 244                 tmp = realloc(args, ++argn * sizeof(arg));
 245
 246                 if (!tmp)
 247                         break;
 248
 249                 args = tmp;
 250                 args[argn-2] = arg;
 251                 args[argn-1] = NULL;
 252         }
 253
 254         va_end(argp);
 255
 256         switch ((pid = fork()))
 257         {
 258         case -1:
 259                 free(args);
 260                 return false;
 261
 262         case 0:
 263                 dup2(pfds[0], 0);
 264
 265                 close(pfds[0]);
 266                 close(pfds[1]);
 267
 268                 close(1);
 269
 270                 if (silent)
 271                         close(2);
 272
 273                 execv(command, args);
 274
 275         default:
 276                 signal(SIGPIPE, SIG_IGN);
 277                 pipe_pid = pid;
 278                 close(pfds[0]);
 279                 fcntl(pfds[1], F_SETFD, fcntl(pfds[1], F_GETFD) | FD_CLOEXEC);
 280         }
 281
 282         pipe_fd = fdopen(pfds[1], "w");
 283         free(args);
 284         return true;
 285 }
 286
 287 void
 288 fw3_pr(const char *fmt, ...)
 289 {
 290         va_list args;
 291
 292         if (fw3_pr_debug && pipe_fd != stdout)
 293         {
 294                 va_start(args, fmt);
 295                 vfprintf(stderr, fmt, args);
 296                 va_end(args);
 297         }
 298
 299         va_start(args, fmt);
 300         vfprintf(pipe_fd, fmt, args);
 301         va_end(args);
 302 }
 303
 304 void
 305 fw3_command_close(void)
 306 {
 307         if (pipe_fd && pipe_fd != stdout)
 308                 fclose(pipe_fd);
 309
 310         if (pipe_pid > -1)
 311                 waitpid(pipe_pid, NULL, 0);
 312
 313         signal(SIGPIPE, SIG_DFL);
 314
 315         pipe_fd = NULL;
 316         pipe_pid = -1;
 317 }
 318
 319 bool
 320 fw3_has_table(bool ipv6, const char *table)
 321 {
 322         FILE *f;
 323
 324         char line[12];
 325         bool seen = false;
 326
 327         const char *path = ipv6
 328                 ? "/proc/net/ip6_tables_names" : "/proc/net/ip_tables_names";
 329
 330         if (!(f = fopen(path, "r")))
 331                 return false;
 332
 333         while (fgets(line, sizeof(line), f))
 334         {
 335                 if (!strncmp(line, table, strlen(table)))
 336                 {
 337                         seen = true;
 338                         break;
 339                 }
 340         }
 341
 342         fclose(f);
 343
 344         return seen;
 345 }
 346
 347
 348 bool
 349 fw3_lock(void)
 350 {
 351         lock_fd = open(FW3_LOCKFILE, O_CREAT|O_WRONLY, S_IRUSR|S_IWUSR);
 352
 353         if (lock_fd < 0)
 354         {
 355                 warn("Cannot create lock file %s: %s", FW3_LOCKFILE, strerror(errno));
 356                 return false;
 357         }
 358
 359         if (flock(lock_fd, LOCK_EX))
 360         {
 361                 warn("Cannot acquire exclusive lock: %s", strerror(errno));
 362                 return false;
 363         }
 364
 365         return true;
 366 }
 367
 368 void
 369 fw3_unlock(void)
 370 {
 371         if (lock_fd < 0)
 372                 return;
 373
 374         if (flock(lock_fd, LOCK_UN))
 375                 warn("Cannot release exclusive lock: %s", strerror(errno));
 376
 377         close(lock_fd);
 378         unlink(FW3_LOCKFILE);
 379
 380         lock_fd = -1;
 381 }
 382
 383
 384 static void
 385 write_defaults_uci(struct uci_context *ctx, struct fw3_defaults *d,
 386                    struct uci_package *dest)
 387 {
 388         char buf[sizeof("0xffffffff\0")];
 389         struct uci_ptr ptr = { .p = dest };
 390
 391         uci_add_section(ctx, dest, "defaults", &ptr.s);
 392
 393         ptr.o      = NULL;
 394         ptr.option = "input";
 395         ptr.value  = fw3_flag_names[d->policy_input];
 396         uci_set(ctx, &ptr);
 397
 398         ptr.o      = NULL;
 399         ptr.option = "output";
 400         ptr.value  = fw3_flag_names[d->policy_output];
 401         uci_set(ctx, &ptr);
 402
 403         ptr.o      = NULL;
 404         ptr.option = "forward";
 405         ptr.value  = fw3_flag_names[d->policy_forward];
 406         uci_set(ctx, &ptr);
 407
 408         sprintf(buf, "0x%x", d->flags[0]);
 409         ptr.o      = NULL;
 410         ptr.option = "__flags_v4";
 411         ptr.value  = buf;
 412         uci_set(ctx, &ptr);
 413
 414         sprintf(buf, "0x%x", d->flags[1]);
 415         ptr.o      = NULL;
 416         ptr.option = "__flags_v6";
 417         ptr.value  = buf;
 418         uci_set(ctx, &ptr);
 419 }
 420
 421 static void
 422 write_zone_uci(struct uci_context *ctx, struct fw3_zone *z,
 423                struct uci_package *dest, struct ifaddrs *ifaddr)
 424 {
 425         struct fw3_device *dev;
 426         struct fw3_address *sub;
 427         struct ifaddrs *ifa;
 428         enum fw3_family fam = FW3_FAMILY_ANY;
 429
 430         char *p, buf[INET6_ADDRSTRLEN];
 431
 432         struct uci_ptr ptr = { .p = dest };
 433
 434         if (!z->enabled)
 435                 return;
 436
 437         if (fw3_no_table(z->flags[0]) && !fw3_no_table(z->flags[1]))
 438                 fam = FW3_FAMILY_V6;
 439         else if (!fw3_no_table(z->flags[0]) && fw3_no_table(z->flags[1]))
 440                 fam = FW3_FAMILY_V4;
 441         else if (fw3_no_table(z->flags[0]) && fw3_no_table(z->flags[1]))
 442                 return;
 443
 444         uci_add_section(ctx, dest, "zone", &ptr.s);
 445
 446         ptr.o      = NULL;
 447         ptr.option = "name";
 448         ptr.value  = z->name;
 449         uci_set(ctx, &ptr);
 450
 451         ptr.o      = NULL;
 452         ptr.option = "input";
 453         ptr.value  = fw3_flag_names[z->policy_input];
 454         uci_set(ctx, &ptr);
 455
 456         ptr.o      = NULL;
 457         ptr.option = "output";
 458         ptr.value  = fw3_flag_names[z->policy_output];
 459         uci_set(ctx, &ptr);
 460
 461         ptr.o      = NULL;
 462         ptr.option = "forward";
 463         ptr.value  = fw3_flag_names[z->policy_forward];
 464         uci_set(ctx, &ptr);
 465
 466         ptr.o      = NULL;
 467         ptr.option = "masq";
 468         ptr.value  = z->masq ? "1" : "0";
 469         uci_set(ctx, &ptr);
 470
 471         ptr.o      = NULL;
 472         ptr.option = "mtu_fix";
 473         ptr.value  = z->mtu_fix ? "1" : "0";
 474         uci_set(ctx, &ptr);
 475
 476         ptr.o      = NULL;
 477         ptr.option = "custom_chains";
 478         ptr.value  = z->custom_chains ? "1" : "0";
 479         uci_set(ctx, &ptr);
 480
 481         if (fam != FW3_FAMILY_ANY)
 482         {
 483                 ptr.o      = NULL;
 484                 ptr.option = "family";
 485                 ptr.value  = fw3_flag_names[fam];
 486                 uci_set(ctx, &ptr);
 487         }
 488
 489         ptr.o      = NULL;
 490         ptr.option = "device";
 491
 492         fw3_foreach(dev, &z->devices)
 493         {
 494                 char *ep;
 495
 496                 if (!dev)
 497                         continue;
 498
 499                 p = buf;
 500                 ep = buf + sizeof(buf);
 501
 502                 if (dev->invert)
 503                         p += snprintf(p, ep - p, "!");
 504
 505                 if (*dev->network)
 506                         p += snprintf(p, ep - p, "%s@%s", dev->name, dev->network);
 507                 else
 508                         p += snprintf(p, ep - p, "%s", dev->name);
 509
 510                 ptr.value = buf;
 511                 uci_add_list(ctx, &ptr);
 512         }
 513
 514         ptr.o      = NULL;
 515         ptr.option = "subnet";
 516
 517         fw3_foreach(sub, &z->subnets)
 518         {
 519                 if (!sub)
 520                         continue;
 521
 522                 ptr.value = fw3_address_to_string(sub, true, false);
 523                 uci_add_list(ctx, &ptr);
 524         }
 525
 526         ptr.o      = NULL;
 527         ptr.option = "__addrs";
 528
 529         fw3_foreach(dev, &z->devices)
 530         {
 531                 if (!dev)
 532                         continue;
 533
 534                 for (ifa = ifaddr; ifa; ifa = ifa->ifa_next)
 535                 {
 536                         if (!ifa->ifa_addr || strcmp(dev->name, ifa->ifa_name))
 537                                 continue;
 538
 539                         if (ifa->ifa_addr->sa_family == AF_INET)
 540                                 inet_ntop(AF_INET,
 541                                           &((struct sockaddr_in *)ifa->ifa_addr)->sin_addr,
 542                                           buf, sizeof(buf));
 543                         else if (ifa->ifa_addr->sa_family == AF_INET6)
 544                                 inet_ntop(AF_INET6,
 545                                           &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr,
 546                                           buf, sizeof(buf));
 547                         else
 548                                 continue;
 549
 550                         ptr.value = buf;
 551                         uci_add_list(ctx, &ptr);
 552                 }
 553         }
 554
 555         sprintf(buf, "0x%x", z->flags[0]);
 556         ptr.o      = NULL;
 557         ptr.option = "__flags_v4";
 558         ptr.value  = buf;
 559         uci_set(ctx, &ptr);
 560
 561         sprintf(buf, "0x%x", z->flags[1]);
 562         ptr.o      = NULL;
 563         ptr.option = "__flags_v6";
 564         ptr.value  = buf;
 565         uci_set(ctx, &ptr);
 566 }
 567
 568 static void
 569 write_ipset_uci(struct uci_context *ctx, struct fw3_ipset *s,
 570                 struct uci_package *dest)
 571 {
 572         struct fw3_ipset_datatype *type;
 573
 574         char buf[sizeof("65535-65535\0")];
 575
 576         struct uci_ptr ptr = { .p = dest };
 577
 578         if (!s->enabled || s->external)
 579                 return;
 580
 581         uci_add_section(ctx, dest, "ipset", &ptr.s);
 582
 583         ptr.o      = NULL;
 584         ptr.option = "name";
 585         ptr.value  = s->name;
 586         uci_set(ctx, &ptr);
 587
 588         ptr.o      = NULL;
 589         ptr.option = "reload_set";
 590         ptr.value  = s->reload_set ? "true" : "false";
 591         uci_set(ctx, &ptr);
 592
 593         ptr.o      = NULL;
 594         ptr.option = "storage";
 595         ptr.value  = fw3_ipset_method_names[s->method];
 596         uci_set(ctx, &ptr);
 597
 598         list_for_each_entry(type, &s->datatypes, list)
 599         {
 600                 sprintf(buf, "%s_%s", type->dir, fw3_ipset_type_names[type->type]);
 601                 ptr.o      = NULL;
 602                 ptr.option = "match";
 603                 ptr.value  = buf;
 604                 uci_add_list(ctx, &ptr);
 605         }
 606
 607         if (s->iprange.set)
 608         {
 609                 ptr.o      = NULL;
 610                 ptr.option = "iprange";
 611                 ptr.value  = fw3_address_to_string(&s->iprange, false, false);
 612                 uci_set(ctx, &ptr);
 613         }
 614
 615         if (s->portrange.set)
 616         {
 617                 sprintf(buf, "%u-%u", s->portrange.port_min, s->portrange.port_max);
 618                 ptr.o      = NULL;
 619                 ptr.option = "portrange";
 620                 ptr.value  = buf;
 621                 uci_set(ctx, &ptr);
 622         }
 623 }
 624
 625 void
 626 fw3_write_statefile(void *state)
 627 {
 628         FILE *sf;
 629         struct fw3_state *s = state;
 630         struct fw3_zone *z;
 631         struct fw3_ipset *i;
 632         struct ifaddrs *ifaddr;
 633
 634         struct uci_package *p;
 635
 636         if (fw3_no_family(s->defaults.flags[0]) &&
 637             fw3_no_family(s->defaults.flags[1]))
 638         {
 639                 unlink(FW3_STATEFILE);
 640         }
 641         else
 642         {
 643                 sf = fopen(FW3_STATEFILE, "w+");
 644
 645                 if (!sf)
 646                 {
 647                         warn("Cannot create state %s: %s", FW3_STATEFILE, strerror(errno));
 648                         return;
 649                 }
 650
 651                 if (getifaddrs(&ifaddr))
 652                 {
 653                         warn("Cannot get interface addresses: %s", strerror(errno));
 654                         ifaddr = NULL;
 655                 }
 656
 657                 if ((p = uci_lookup_package(s->uci, "fw3_state")) != NULL)
 658                         uci_unload(s->uci, p);
 659
 660                 uci_import(s->uci, sf, "fw3_state", NULL, true);
 661
 662                 if ((p = uci_lookup_package(s->uci, "fw3_state")) != NULL)
 663                 {
 664                         write_defaults_uci(s->uci, &s->defaults, p);
 665
 666                         list_for_each_entry(z, &s->zones, list)
 667                                 write_zone_uci(s->uci, z, p, ifaddr);
 668
 669                         list_for_each_entry(i, &s->ipsets, list)
 670                                 write_ipset_uci(s->uci, i, p);
 671
 672                         uci_export(s->uci, sf, p, true);
 673                         uci_unload(s->uci, p);
 674                 }
 675
 676                 fsync(fileno(sf));
 677                 fclose(sf);
 678
 679                 if (ifaddr)
 680                         freeifaddrs(ifaddr);
 681         }
 682 }
 683
 684
 685 void
 686 fw3_free_object(void *obj, const void *opts)
 687 {
 688         const struct fw3_option *ol;
 689         struct list_head *list, *cur, *tmp;
 690
 691         for (ol = opts; ol->name; ol++)
 692         {
 693                 if (!ol->elem_size)
 694                         continue;
 695
 696                 list = (struct list_head *)((char *)obj + ol->offset);
 697                 list_for_each_safe(cur, tmp, list)
 698                 {
 699                         list_del(cur);
 700                         free(cur);
 701                 }
 702         }
 703
 704         free(obj);
 705 }
 706
 707 void
 708 fw3_free_list(struct list_head *head)
 709 {
 710         struct list_head *entry, *tmp;
 711
 712         if (!head)
 713                 return;
 714
 715         list_for_each_safe(entry, tmp, head)
 716         {
 717                 list_del(entry);
 718                 free(entry);
 719         }
 720
 721         free(head);
 722 }
 723
 724 bool
 725 fw3_hotplug(bool add, void *zone, void *device)
 726 {
 727         struct fw3_zone *z = zone;
 728         struct fw3_device *d = device;
 729
 730         if (!*d->network)
 731                 return false;
 732
 733         switch (fork())
 734         {
 735         case -1:
 736                 warn("Unable to fork(): %s\n", strerror(errno));
 737                 return false;
 738
 739         case 0:
 740                 break;
 741
 742         default:
 743                 return true;
 744         }
 745
 746         close(0);
 747         close(1);
 748         close(2);
 749         if (chdir("/")) {};
 750
 751         clearenv();
 752         setenv("ACTION",    add ? "add" : "remove", 1);
 753         setenv("ZONE",      z->name,                1);
 754         setenv("INTERFACE", d->network,             1);
 755         setenv("DEVICE",    d->name,                1);
 756
 757         execl(FW3_HOTPLUG, FW3_HOTPLUG, "firewall", NULL);
 758
 759         /* unreached */
 760         return false;
 761 }
 762
 763 int
 764 fw3_netmask2bitlen(int family, void *mask)
 765 {
 766         int bits;
 767         struct in_addr *v4;
 768         struct in6_addr *v6;
 769
 770         if (family == FW3_FAMILY_V6)
 771                 for (bits = 0, v6 = mask;
 772                      bits < 128 && (v6->s6_addr[bits / 8] << (bits % 8)) & 128;
 773                      bits++);
 774         else
 775                 for (bits = 0, v4 = mask;
 776                      bits < 32 && (ntohl(v4->s_addr) << bits) & 0x80000000;
 777                      bits++);
 778
 779         return bits;
 780 }
 781
 782 bool
 783 fw3_bitlen2netmask(int family, int bits, void *mask)
 784 {
 785         int i;
 786         uint8_t rem, b;
 787         struct in_addr *v4;
 788         struct in6_addr *v6;
 789
 790         if (family == FW3_FAMILY_V6)
 791         {
 792                 if (bits < -128 || bits > 128)
 793                         return false;
 794
 795                 v6 = mask;
 796                 rem = abs(bits);
 797
 798                 for (i = 0; i < sizeof(v6->s6_addr); i++)
 799                 {
 800                         b = (rem > 8) ? 8 : rem;
 801                         v6->s6_addr[i] = (uint8_t)(0xFF << (8 - b));
 802                         rem -= b;
 803                 }
 804
 805                 if (bits < 0)
 806                         for (i = 0; i < sizeof(v6->s6_addr); i++)
 807                                 v6->s6_addr[i] = ~v6->s6_addr[i];
 808         }
 809         else
 810         {
 811                 if (bits < -32 || bits > 32)
 812                         return false;
 813
 814                 v4 = mask;
 815                 v4->s_addr = bits ? htonl(~((1 << (32 - abs(bits))) - 1)) : 0;
 816
 817                 if (bits < 0)
 818                         v4->s_addr = ~v4->s_addr;
 819         }
 820
 821         return true;
 822 }
 823
 824 void
 825 fw3_flush_conntrack(void *state)
 826 {
 827         bool found;
 828         struct fw3_state *s = state;
 829         struct fw3_address *addr;
 830         struct fw3_device *dev;
 831         struct fw3_zone *zone;
 832         struct ifaddrs *ifaddr, *ifa;
 833         struct sockaddr_in *sin;
 834         struct sockaddr_in6 *sin6;
 835         char buf[INET6_ADDRSTRLEN];
 836         FILE *ct;
 837
 838         if (!state)
 839         {
 840                 if ((ct = fopen("/proc/net/nf_conntrack", "w")) != NULL)
 841                 {
 842                         info(" * Flushing conntrack table ...");
 843
 844                         fwrite("f\n", 1, 2, ct);
 845                         fclose(ct);
 846                 }
 847
 848                 return;
 849         }
 850
 851         if (getifaddrs(&ifaddr))
 852         {
 853                 warn("Cannot get interface addresses: %s", strerror(errno));
 854                 return;
 855         }
 856
 857         if ((ct = fopen("/proc/net/nf_conntrack", "w")) != NULL)
 858         {
 859                 list_for_each_entry(zone, &s->zones, list)
 860                 list_for_each_entry(addr, &zone->old_addrs, list)
 861                 {
 862                         found = false;
 863
 864                         list_for_each_entry(dev, &zone->devices, list)
 865                         {
 866                                 for (ifa = ifaddr; ifa && !found; ifa = ifa->ifa_next)
 867                                 {
 868                                         if (!ifa->ifa_addr || strcmp(dev->name, ifa->ifa_name))
 869                                                 continue;
 870
 871                                         sin = (struct sockaddr_in *)ifa->ifa_addr;
 872                                         sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
 873
 874                                         if (addr->family == FW3_FAMILY_V4 &&
 875                                                 sin->sin_family == AF_INET)
 876                                         {
 877                                                 found = !memcmp(&addr->address.v4, &sin->sin_addr,
 878                                                                                 sizeof(sin->sin_addr));
 879                                         }
 880                                         else if (addr->family == FW3_FAMILY_V6 &&
 881                                                          sin6->sin6_family == AF_INET6)
 882                                         {
 883                                                 found = !memcmp(&addr->address.v6, &sin6->sin6_addr,
 884                                                                                 sizeof(sin6->sin6_addr));
 885                                         }
 886                                 }
 887
 888                                 if (found)
 889                                         break;
 890                         }
 891
 892                         if (!found)
 893                         {
 894                                 inet_ntop(addr->family == FW3_FAMILY_V4 ? AF_INET : AF_INET6,
 895                                                   &addr->address.v4, buf, sizeof(buf));
 896
 897                                 info(" * Flushing conntrack: %s", buf);
 898                                 fprintf(ct, "%s\n", buf);
 899                         }
 900                 }
 901
 902                 fclose(ct);
 903         }
 904
 905         freeifaddrs(ifaddr);
 906 }
 907
 908 bool fw3_attr_parse_name_type(struct blob_attr *entry, const char **name, const char **type)
 909 {
 910         struct blob_attr *opt;
 911         unsigned orem;
 912
 913         if (!type || !name)
 914                 return false;
 915
 916         *type = NULL;
 917
 918         blobmsg_for_each_attr(opt, entry, orem)
 919                 if (!strcmp(blobmsg_name(opt), "type"))
 920                         *type = blobmsg_get_string(opt);
 921                 else if (!strcmp(blobmsg_name(opt), "name"))
 922                         *name = blobmsg_get_string(opt);
 923
 924         return *type != NULL ? true : false;
 925 }
 926
 927 const char *
 928 fw3_protoname(void *proto)
 929 {
 930         static char buf[sizeof("4294967295")];
 931         struct fw3_protocol *p = proto;
 932         struct protoent *pe;
 933
 934         if (!p)
 935                 return "?";
 936
 937         pe = getprotobynumber(p->protocol);
 938
 939         if (!pe)
 940         {
 941                 snprintf(buf, sizeof(buf), "%u", p->protocol);
 942                 return buf;
 943         }
 944
 945         return pe->p_name;
 946 }
 947
 948 bool
 949 fw3_check_loopback_dev(const char *name)
 950 {
 951         struct ifreq ifr;
 952         int s;
 953         bool rv = false;
 954
 955         s = socket(AF_LOCAL, SOCK_DGRAM, 0);
 956
 957         if (s < 0)
 958                 return false;
 959
 960         memset(&ifr, 0, sizeof(ifr));
 961         strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name) - 1);
 962
 963         if (ioctl(s, SIOCGIFFLAGS, &ifr) >= 0) {
 964                 if (ifr.ifr_flags & IFF_LOOPBACK)
 965                         rv = true;
 966         }
 967
 968         close(s);
 969
 970         return rv;
 971 }
 972
 973 bool
 974 fw3_check_loopback_addr(struct fw3_address *addr)
 975 {
 976         if (addr->family == FW3_FAMILY_V4 &&
 977             (ntohl(addr->address.v4.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET)
 978                 return true;
 979
 980         if (addr->family == FW3_FAMILY_V6 && !addr->range &&
 981             fw3_netmask2bitlen(FW3_FAMILY_V6, &addr->mask.v6) == 128 &&
 982             IN6_IS_ADDR_LOOPBACK(&addr->address.v6))
 983                 return true;
 984
 985         return false;
 986 }