src/network.c

   1 /*
   2         libloc - A library to determine the location of someone on the Internet
   3
   4         Copyright (C) 2017 IPFire Development Team <info@ipfire.org>
   5
   6         This library is free software; you can redistribute it and/or
   7         modify it under the terms of the GNU Lesser General Public
   8         License as published by the Free Software Foundation; either
   9         version 2.1 of the License, or (at your option) any later version.
  10
  11         This library is distributed in the hope that it will be useful,
  12         but WITHOUT ANY WARRANTY; without even the implied warranty of
  13         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14         Lesser General Public License for more details.
  15 */
  16
  17 #include <arpa/inet.h>
  18 #include <assert.h>
  19 #include <errno.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23
  24 #ifdef HAVE_ENDIAN_H
  25 #  include <endian.h>
  26 #endif
  27
  28 #include <loc/libloc.h>
  29 #include <loc/compat.h>
  30 #include <loc/country.h>
  31 #include <loc/network.h>
  32 #include <loc/network-list.h>
  33 #include <loc/private.h>
  34
  35 struct loc_network {
  36         struct loc_ctx* ctx;
  37         int refcount;
  38
  39         int family;
  40         struct in6_addr first_address;
  41         struct in6_addr last_address;
  42         unsigned int prefix;
  43
  44         char country_code[3];
  45         uint32_t asn;
  46         enum loc_network_flags flags;
  47 };
  48
  49 static int valid_prefix(struct in6_addr* address, unsigned int prefix) {
  50         // The prefix cannot be larger than 128 bits
  51         if (prefix > 128)
  52                 return 1;
  53
  54         // And the prefix cannot be zero
  55         if (prefix == 0)
  56                 return 1;
  57
  58         // For IPv4-mapped addresses the prefix has to be 96 or lager
  59         if (IN6_IS_ADDR_V4MAPPED(address) && prefix <= 96)
  60                 return 1;
  61
  62         return 0;
  63 }
  64
  65 static struct in6_addr prefix_to_bitmask(unsigned int prefix) {
  66         struct in6_addr bitmask;
  67
  68         for (unsigned int i = 0; i < 16; i++)
  69                 bitmask.s6_addr[i] = 0;
  70
  71         for (int i = prefix, j = 0; i > 0; i -= 8, j++) {
  72                 if (i >= 8)
  73                         bitmask.s6_addr[j] = 0xff;
  74                 else
  75                         bitmask.s6_addr[j] = 0xff << (8 - i);
  76         }
  77
  78         return bitmask;
  79 }
  80
  81 static struct in6_addr make_first_address(const struct in6_addr* address, const struct in6_addr* bitmask) {
  82         struct in6_addr a;
  83
  84         // Perform bitwise AND
  85         for (unsigned int i = 0; i < 4; i++)
  86                 a.s6_addr32[i] = address->s6_addr32[i] & bitmask->s6_addr32[i];
  87
  88         return a;
  89 }
  90
  91 static struct in6_addr make_last_address(const struct in6_addr* address, const struct in6_addr* bitmask) {
  92         struct in6_addr a;
  93
  94         // Perform bitwise OR
  95         for (unsigned int i = 0; i < 4; i++)
  96                 a.s6_addr32[i] = address->s6_addr32[i] | ~bitmask->s6_addr32[i];
  97
  98         return a;
  99 }
 100
 101 static struct in6_addr address_increment(const struct in6_addr* address) {
 102         struct in6_addr a = *address;
 103
 104         for (int octet = 15; octet >= 0; octet--) {
 105                 if (a.s6_addr[octet] < 255) {
 106                         a.s6_addr[octet]++;
 107                         break;
 108                 } else {
 109                         a.s6_addr[octet] = 0;
 110                 }
 111         }
 112
 113         return a;
 114 }
 115
 116 LOC_EXPORT int loc_network_new(struct loc_ctx* ctx, struct loc_network** network,
 117                 struct in6_addr* address, unsigned int prefix) {
 118         // Address cannot be unspecified
 119         if (IN6_IS_ADDR_UNSPECIFIED(address)) {
 120                 DEBUG(ctx, "Start address is unspecified\n");
 121                 return -EINVAL;
 122         }
 123
 124         // Address cannot be loopback
 125         if (IN6_IS_ADDR_LOOPBACK(address)) {
 126                 DEBUG(ctx, "Start address is loopback address\n");
 127                 return -EINVAL;
 128         }
 129
 130         // Address cannot be link-local
 131         if (IN6_IS_ADDR_LINKLOCAL(address)) {
 132                 DEBUG(ctx, "Start address cannot be link-local\n");
 133                 return -EINVAL;
 134         }
 135
 136         // Address cannot be site-local
 137         if (IN6_IS_ADDR_SITELOCAL(address)) {
 138                 DEBUG(ctx, "Start address cannot be site-local\n");
 139                 return -EINVAL;
 140         }
 141
 142         // Validate the prefix
 143         if (valid_prefix(address, prefix) != 0) {
 144                 DEBUG(ctx, "Invalid prefix: %u\n", prefix);
 145                 return -EINVAL;
 146         }
 147
 148         struct loc_network* n = calloc(1, sizeof(*n));
 149         if (!n)
 150                 return -ENOMEM;
 151
 152         n->ctx = loc_ref(ctx);
 153         n->refcount = 1;
 154
 155         // Store the prefix
 156         n->prefix = prefix;
 157
 158         // Convert the prefix into a bitmask
 159         struct in6_addr bitmask = prefix_to_bitmask(n->prefix);
 160
 161         // Store the first and last address in the network
 162         n->first_address = make_first_address(address, &bitmask);
 163         n->last_address = make_last_address(&n->first_address, &bitmask);
 164
 165         // Set family
 166         if (IN6_IS_ADDR_V4MAPPED(&n->first_address))
 167                 n->family = AF_INET;
 168         else
 169                 n->family = AF_INET6;
 170
 171         DEBUG(n->ctx, "Network allocated at %p\n", n);
 172         *network = n;
 173         return 0;
 174 }
 175
 176 LOC_EXPORT int loc_network_new_from_string(struct loc_ctx* ctx, struct loc_network** network,
 177                 const char* address_string) {
 178         struct in6_addr first_address;
 179         char* prefix_string;
 180         unsigned int prefix = 128;
 181         int r = -EINVAL;
 182
 183         DEBUG(ctx, "Attempting to parse network %s\n", address_string);
 184
 185         // Make a copy of the string to work on it
 186         char* buffer = strdup(address_string);
 187         address_string = prefix_string = buffer;
 188
 189         // Split address and prefix
 190         address_string = strsep(&prefix_string, "/");
 191
 192         DEBUG(ctx, "  Split into address = %s, prefix = %s\n", address_string, prefix_string);
 193
 194         // Parse the address
 195         r = loc_parse_address(ctx, address_string, &first_address);
 196         if (r) {
 197                 DEBUG(ctx, "The address could not be parsed\n");
 198                 goto FAIL;
 199         }
 200
 201         // If a prefix was given, we will try to parse it
 202         if (prefix_string) {
 203                 // Convert prefix to integer
 204                 prefix = strtol(prefix_string, NULL, 10);
 205
 206                 if (!prefix) {
 207                         DEBUG(ctx, "The prefix was not parsable: %s\n", prefix_string);
 208                         goto FAIL;
 209                 }
 210
 211                 // Map the prefix to IPv6 if needed
 212                 if (IN6_IS_ADDR_V4MAPPED(&first_address))
 213                         prefix += 96;
 214         }
 215
 216 FAIL:
 217         // Free temporary buffer
 218         free(buffer);
 219
 220         // Exit if the parsing was unsuccessful
 221         if (r)
 222                 return r;
 223
 224         // Create a new network
 225         return loc_network_new(ctx, network, &first_address, prefix);
 226 }
 227
 228 LOC_EXPORT struct loc_network* loc_network_ref(struct loc_network* network) {
 229         network->refcount++;
 230
 231         return network;
 232 }
 233
 234 static void loc_network_free(struct loc_network* network) {
 235         DEBUG(network->ctx, "Releasing network at %p\n", network);
 236
 237         loc_unref(network->ctx);
 238         free(network);
 239 }
 240
 241 LOC_EXPORT struct loc_network* loc_network_unref(struct loc_network* network) {
 242         if (!network)
 243                 return NULL;
 244
 245         if (--network->refcount > 0)
 246                 return network;
 247
 248         loc_network_free(network);
 249         return NULL;
 250 }
 251
 252 static int format_ipv6_address(const struct in6_addr* address, char* string, size_t length) {
 253         const char* ret = inet_ntop(AF_INET6, address, string, length);
 254         if (!ret)
 255                 return -1;
 256
 257         return 0;
 258 }
 259
 260 static int format_ipv4_address(const struct in6_addr* address, char* string, size_t length) {
 261         struct in_addr ipv4_address;
 262         ipv4_address.s_addr = address->s6_addr32[3];
 263
 264         const char* ret = inet_ntop(AF_INET, &ipv4_address, string, length);
 265         if (!ret)
 266                 return -1;
 267
 268         return 0;
 269 }
 270
 271 LOC_EXPORT char* loc_network_str(struct loc_network* network) {
 272         int r;
 273         const size_t length = INET6_ADDRSTRLEN + 4;
 274
 275         char* string = malloc(length);
 276         if (!string)
 277                 return NULL;
 278
 279         unsigned int prefix = network->prefix;
 280
 281         switch (network->family) {
 282                 case AF_INET6:
 283                         r = format_ipv6_address(&network->first_address, string, length);
 284                         break;
 285
 286                 case AF_INET:
 287                         r = format_ipv4_address(&network->first_address, string, length);
 288                         prefix -= 96;
 289                         break;
 290
 291                 default:
 292                         r = -1;
 293                         break;
 294         }
 295
 296         if (r) {
 297                 ERROR(network->ctx, "Could not convert network to string: %s\n", strerror(errno));
 298                 free(string);
 299
 300                 return NULL;
 301         }
 302
 303         // Append prefix
 304         sprintf(string + strlen(string), "/%u", prefix);
 305
 306         return string;
 307 }
 308
 309 LOC_EXPORT int loc_network_address_family(struct loc_network* network) {
 310         return network->family;
 311 }
 312
 313 LOC_EXPORT unsigned int loc_network_prefix(struct loc_network* network) {
 314         switch (network->family) {
 315                 case AF_INET6:
 316                         return network->prefix;
 317
 318                 case AF_INET:
 319                         return network->prefix - 96;
 320         }
 321
 322         return 0;
 323 }
 324
 325 static char* loc_network_format_address(struct loc_network* network, const struct in6_addr* address) {
 326         const size_t length = INET6_ADDRSTRLEN;
 327
 328         char* string = malloc(length);
 329         if (!string)
 330                 return NULL;
 331
 332         int r = 0;
 333
 334         switch (network->family) {
 335                 case AF_INET6:
 336                         r = format_ipv6_address(address, string, length);
 337                         break;
 338
 339                 case AF_INET:
 340                         r = format_ipv4_address(address, string, length);
 341                         break;
 342
 343                 default:
 344                         r = -1;
 345                         break;
 346         }
 347
 348         if (r) {
 349                 ERROR(network->ctx, "Could not format IP address to string: %s\n", strerror(errno));
 350                 free(string);
 351
 352                 return NULL;
 353         }
 354
 355         return string;
 356 }
 357
 358 LOC_EXPORT const struct in6_addr* loc_network_get_first_address(struct loc_network* network) {
 359         return &network->first_address;
 360 }
 361
 362 LOC_EXPORT char* loc_network_format_first_address(struct loc_network* network) {
 363         return loc_network_format_address(network, &network->first_address);
 364 }
 365
 366 LOC_EXPORT const struct in6_addr* loc_network_get_last_address(struct loc_network* network) {
 367         return &network->last_address;
 368 }
 369
 370 LOC_EXPORT char* loc_network_format_last_address(struct loc_network* network) {
 371         return loc_network_format_address(network, &network->last_address);
 372 }
 373
 374 LOC_EXPORT int loc_network_match_address(struct loc_network* network, const struct in6_addr* address) {
 375         // Address must be larger than the start address
 376         if (in6_addr_cmp(&network->first_address, address) > 0)
 377                 return 0;
 378
 379         // Address must be smaller than the last address
 380         if (in6_addr_cmp(&network->last_address, address) < 0)
 381                 return 0;
 382
 383         // The address is inside this network
 384         return 1;
 385 }
 386
 387 LOC_EXPORT const char* loc_network_get_country_code(struct loc_network* network) {
 388         return network->country_code;
 389 }
 390
 391 LOC_EXPORT int loc_network_set_country_code(struct loc_network* network, const char* country_code) {
 392         // Set empty country code
 393         if (!country_code || !*country_code) {
 394                 *network->country_code = '\0';
 395                 return 0;
 396         }
 397
 398         // Check country code
 399         if (!loc_country_code_is_valid(country_code))
 400                 return -EINVAL;
 401
 402         loc_country_code_copy(network->country_code, country_code);
 403
 404         return 0;
 405 }
 406
 407 LOC_EXPORT int loc_network_match_country_code(struct loc_network* network, const char* country_code) {
 408         // Check country code
 409         if (!loc_country_code_is_valid(country_code))
 410                 return -EINVAL;
 411
 412         return (network->country_code[0] == country_code[0])
 413                 && (network->country_code[1] == country_code[1]);
 414 }
 415
 416 LOC_EXPORT uint32_t loc_network_get_asn(struct loc_network* network) {
 417         return network->asn;
 418 }
 419
 420 LOC_EXPORT int loc_network_set_asn(struct loc_network* network, uint32_t asn) {
 421         network->asn = asn;
 422
 423         return 0;
 424 }
 425
 426 LOC_EXPORT int loc_network_match_asn(struct loc_network* network, uint32_t asn) {
 427         return network->asn == asn;
 428 }
 429
 430 LOC_EXPORT int loc_network_has_flag(struct loc_network* network, uint32_t flag) {
 431         return network->flags & flag;
 432 }
 433
 434 LOC_EXPORT int loc_network_set_flag(struct loc_network* network, uint32_t flag) {
 435         network->flags |= flag;
 436
 437         return 0;
 438 }
 439
 440 LOC_EXPORT int loc_network_match_flag(struct loc_network* network, uint32_t flag) {
 441         return loc_network_has_flag(network, flag);
 442 }
 443
 444 LOC_EXPORT int loc_network_cmp(struct loc_network* self, struct loc_network* other) {
 445         // Compare address
 446         int r = in6_addr_cmp(&self->first_address, &other->first_address);
 447         if (r)
 448                 return r;
 449
 450         // Compare prefix
 451         if (self->prefix > other->prefix)
 452                 return 1;
 453         else if (self->prefix < other->prefix)
 454                 return -1;
 455
 456         // Both networks are equal
 457         return 0;
 458 }
 459
 460 LOC_EXPORT int loc_network_overlaps(struct loc_network* self, struct loc_network* other) {
 461         // Either of the start addresses must be in the other subnet
 462         if (loc_network_match_address(self, &other->first_address))
 463                 return 1;
 464
 465         if (loc_network_match_address(other, &self->first_address))
 466                 return 1;
 467
 468         // Or either of the end addresses is in the other subnet
 469         if (loc_network_match_address(self, &other->last_address))
 470                 return 1;
 471
 472         if (loc_network_match_address(other, &self->last_address))
 473                 return 1;
 474
 475         return 0;
 476 }
 477
 478 LOC_EXPORT int loc_network_is_subnet(struct loc_network* self, struct loc_network* other) {
 479         // The prefix must be smaller (this avoids the more complex comparisons later)
 480         if (self->prefix > other->prefix)
 481                 return 0;
 482
 483         // If the start address of the other network is smaller than this network,
 484         // it cannot be a subnet.
 485         if (in6_addr_cmp(&self->first_address, &other->first_address) > 0)
 486                 return 0;
 487
 488         // If the end address of the other network is greater than this network,
 489         // it cannot be a subnet.
 490         if (in6_addr_cmp(&self->last_address, &other->last_address) < 0)
 491                 return 0;
 492
 493         return 1;
 494 }
 495
 496 LOC_EXPORT int loc_network_subnets(struct loc_network* network,
 497                 struct loc_network** subnet1, struct loc_network** subnet2) {
 498         int r;
 499         *subnet1 = NULL;
 500         *subnet2 = NULL;
 501
 502         // New prefix length
 503         unsigned int prefix = network->prefix + 1;
 504
 505         // Check if the new prefix is valid
 506         if (valid_prefix(&network->first_address, prefix))
 507                 return -1;
 508
 509         // Create the first half of the network
 510         r = loc_network_new(network->ctx, subnet1, &network->first_address, prefix);
 511         if (r)
 512                 return r;
 513
 514         // The next subnet starts after the first one
 515         struct in6_addr first_address = address_increment(&(*subnet1)->last_address);
 516
 517         // Create the second half of the network
 518         r = loc_network_new(network->ctx, subnet2, &first_address, prefix);
 519         if (r)
 520                 return r;
 521
 522         // Copy country code
 523         const char* country_code = loc_network_get_country_code(network);
 524         if (country_code) {
 525                 loc_network_set_country_code(*subnet1, country_code);
 526                 loc_network_set_country_code(*subnet2, country_code);
 527         }
 528
 529         // Copy ASN
 530         uint32_t asn = loc_network_get_asn(network);
 531         if (asn) {
 532                 loc_network_set_asn(*subnet1, asn);
 533                 loc_network_set_asn(*subnet2, asn);
 534         }
 535
 536         return 0;
 537 }
 538
 539 static int __loc_network_exclude(struct loc_network* network,
 540                 struct loc_network* other, struct loc_network_list* list) {
 541         struct loc_network* subnet1 = NULL;
 542         struct loc_network* subnet2 = NULL;
 543
 544         int r = loc_network_subnets(network, &subnet1, &subnet2);
 545         if (r)
 546                 goto ERROR;
 547
 548         if (loc_network_cmp(other, subnet1) == 0) {
 549                 r = loc_network_list_push(list, subnet2);
 550                 if (r)
 551                         goto ERROR;
 552
 553         } else if (loc_network_cmp(other, subnet2) == 0) {
 554                 r = loc_network_list_push(list, subnet1);
 555                 if (r)
 556                         goto ERROR;
 557
 558         } else  if (loc_network_is_subnet(subnet1, other)) {
 559                 r = loc_network_list_push(list, subnet2);
 560                 if (r)
 561                         goto ERROR;
 562
 563                 r = __loc_network_exclude(subnet1, other, list);
 564                 if (r)
 565                         goto ERROR;
 566
 567         } else if (loc_network_is_subnet(subnet2, other)) {
 568                 r = loc_network_list_push(list, subnet1);
 569                 if (r)
 570                         goto ERROR;
 571
 572                 r = __loc_network_exclude(subnet2, other, list);
 573                 if (r)
 574                         goto ERROR;
 575
 576         } else {
 577                 ERROR(network->ctx, "We should never get here\n");
 578                 r = 1;
 579                 goto ERROR;
 580         }
 581
 582 ERROR:
 583         if (subnet1)
 584                 loc_network_unref(subnet1);
 585
 586         if (subnet2)
 587                 loc_network_unref(subnet2);
 588
 589         return r;
 590 }
 591
 592 static int __loc_network_exclude_to_list(struct loc_network* self,
 593                 struct loc_network* other, struct loc_network_list* list) {
 594         // Other must be a subnet of self
 595         if (!loc_network_is_subnet(self, other)) {
 596                 DEBUG(self->ctx, "Network %p is not contained in network %p\n", other, self);
 597
 598                 // Exit silently
 599                 return 0;
 600         }
 601
 602         // We cannot perform this operation if both networks equal
 603         if (loc_network_cmp(self, other) == 0) {
 604                 DEBUG(self->ctx, "Networks %p and %p are equal\n", self, other);
 605
 606                 // Exit silently
 607                 return 0;
 608         }
 609
 610         return __loc_network_exclude(self, other, list);
 611 }
 612
 613 LOC_EXPORT struct loc_network_list* loc_network_exclude(
 614                 struct loc_network* self, struct loc_network* other) {
 615         struct loc_network_list* list;
 616
 617 #ifdef ENABLE_DEBUG
 618         char* n1 = loc_network_str(self);
 619         char* n2 = loc_network_str(other);
 620
 621         DEBUG(self->ctx, "Returning %s excluding %s...\n", n1, n2);
 622
 623         free(n1);
 624         free(n2);
 625 #endif
 626
 627         // Create a new list with the result
 628         int r = loc_network_list_new(self->ctx, &list);
 629         if (r) {
 630                 ERROR(self->ctx, "Could not create network list: %d\n", r);
 631
 632                 return NULL;
 633         }
 634
 635         r = __loc_network_exclude_to_list(self, other, list);
 636         if (r) {
 637                 loc_network_list_unref(list);
 638
 639                 return NULL;
 640         }
 641
 642         // Return the result
 643         return list;
 644 }
 645
 646 LOC_EXPORT struct loc_network_list* loc_network_exclude_list(
 647                 struct loc_network* network, struct loc_network_list* list) {
 648         struct loc_network_list* to_check;
 649
 650         // Create a new list with all networks to look at
 651         int r = loc_network_list_new(network->ctx, &to_check);
 652         if (r)
 653                 return NULL;
 654
 655         struct loc_network* subnet = NULL;
 656         struct loc_network_list* subnets = NULL;
 657
 658         for (unsigned int i = 0; i < loc_network_list_size(list); i++) {
 659                 subnet = loc_network_list_get(list, i);
 660
 661                 // Find all excluded networks
 662                 if (!loc_network_list_contains(to_check, subnet)) {
 663                         r = __loc_network_exclude_to_list(network, subnet, to_check);
 664                         if (r) {
 665                                 loc_network_list_unref(to_check);
 666                                 loc_network_unref(subnet);
 667
 668                                 return NULL;
 669                         }
 670                 }
 671
 672                 // Cleanup
 673                 loc_network_unref(subnet);
 674         }
 675
 676         r = loc_network_list_new(network->ctx, &subnets);
 677         if (r) {
 678                 loc_network_list_unref(to_check);
 679                 return NULL;
 680         }
 681
 682         off_t smallest_subnet = 0;
 683
 684         while (!loc_network_list_empty(to_check)) {
 685                 struct loc_network* subnet_to_check = loc_network_list_pop_first(to_check);
 686
 687                 // Check whether the subnet to check is part of the input list
 688                 if (loc_network_list_contains(list, subnet_to_check)) {
 689                         loc_network_unref(subnet_to_check);
 690                         continue;
 691                 }
 692
 693                 // Marks whether this subnet passed all checks
 694                 int passed = 1;
 695
 696                 for (unsigned int i = smallest_subnet; i < loc_network_list_size(list); i++) {
 697                         subnet = loc_network_list_get(list, i);
 698
 699                         // Drop this subnet if is a subnet of another subnet
 700                         if (loc_network_is_subnet(subnet, subnet_to_check)) {
 701                                 passed = 0;
 702                                 loc_network_unref(subnet);
 703                                 break;
 704                         }
 705
 706                         // Break it down if it overlaps
 707                         if (loc_network_overlaps(subnet, subnet_to_check)) {
 708                                 passed = 0;
 709
 710                                 __loc_network_exclude_to_list(subnet_to_check, subnet, to_check);
 711
 712                                 loc_network_unref(subnet);
 713                                 break;
 714                         }
 715
 716                         // If the subnet is strictly greater, we do not need to continue the search
 717                         r = loc_network_cmp(subnet, subnet_to_check);
 718                         if (r > 0) {
 719                                 loc_network_unref(subnet);
 720                                 break;
 721
 722                         // If it is strictly smaller, we can continue the search from here next
 723                         // time because all networks that are to be checked can only be larger
 724                         // than this one.
 725                         } else if (r < 0) {
 726                                 smallest_subnet = i;
 727                         }
 728
 729                         loc_network_unref(subnet);
 730                 }
 731
 732                 if (passed) {
 733                         r = loc_network_list_push(subnets, subnet_to_check);
 734                 }
 735
 736                 loc_network_unref(subnet_to_check);
 737         }
 738
 739         loc_network_list_unref(to_check);
 740
 741         // Sort the result
 742         loc_network_list_sort(subnets);
 743
 744         return subnets;
 745 }
 746
 747 LOC_EXPORT int loc_network_to_database_v1(struct loc_network* network, struct loc_database_network_v1* dbobj) {
 748         // Add country code
 749         loc_country_code_copy(dbobj->country_code, network->country_code);
 750
 751         // Add ASN
 752         dbobj->asn = htobe32(network->asn);
 753
 754         // Flags
 755         dbobj->flags = htobe16(network->flags);
 756
 757         return 0;
 758 }
 759
 760 LOC_EXPORT int loc_network_new_from_database_v1(struct loc_ctx* ctx, struct loc_network** network,
 761                 struct in6_addr* address, unsigned int prefix, const struct loc_database_network_v1* dbobj) {
 762         char country_code[3] = "\0\0";
 763
 764         int r = loc_network_new(ctx, network, address, prefix);
 765         if (r) {
 766                 ERROR(ctx, "Could not allocate a new network: %s", strerror(-r));
 767                 return r;
 768         }
 769
 770         // Import country code
 771         loc_country_code_copy(country_code, dbobj->country_code);
 772
 773         r = loc_network_set_country_code(*network, country_code);
 774         if (r) {
 775                 ERROR(ctx, "Could not set country code: %s\n", country_code);
 776                 return r;
 777         }
 778
 779         // Import ASN
 780         uint32_t asn = be32toh(dbobj->asn);
 781         r = loc_network_set_asn(*network, asn);
 782         if (r) {
 783                 ERROR(ctx, "Could not set ASN: %d\n", asn);
 784                 return r;
 785         }
 786
 787         // Import flags
 788         int flags = be16toh(dbobj->flags);
 789         r = loc_network_set_flag(*network, flags);
 790         if (r) {
 791                 ERROR(ctx, "Could not set flags: %d\n", flags);
 792                 return r;
 793         }
 794
 795         return 0;
 796 }
 797
 798 struct loc_network_tree {
 799         struct loc_ctx* ctx;
 800         int refcount;
 801
 802         struct loc_network_tree_node* root;
 803 };
 804
 805 struct loc_network_tree_node {
 806         struct loc_ctx* ctx;
 807         int refcount;
 808
 809         struct loc_network_tree_node* zero;
 810         struct loc_network_tree_node* one;
 811
 812         struct loc_network* network;
 813 };
 814
 815 int loc_network_tree_new(struct loc_ctx* ctx, struct loc_network_tree** tree) {
 816         struct loc_network_tree* t = calloc(1, sizeof(*t));
 817         if (!t)
 818                 return -ENOMEM;
 819
 820         t->ctx = loc_ref(ctx);
 821         t->refcount = 1;
 822
 823         // Create the root node
 824         int r = loc_network_tree_node_new(ctx, &t->root);
 825         if (r) {
 826                 loc_network_tree_unref(t);
 827                 return r;
 828         }
 829
 830         DEBUG(t->ctx, "Network tree allocated at %p\n", t);
 831         *tree = t;
 832         return 0;
 833 }
 834
 835 struct loc_network_tree_node* loc_network_tree_get_root(struct loc_network_tree* tree) {
 836         return loc_network_tree_node_ref(tree->root);
 837 }
 838
 839 static struct loc_network_tree_node* loc_network_tree_get_node(struct loc_network_tree_node* node, int path) {
 840         struct loc_network_tree_node** n;
 841
 842         if (path == 0)
 843                 n = &node->zero;
 844         else
 845                 n = &node->one;
 846
 847         // If the desired node doesn't exist, yet, we will create it
 848         if (*n == NULL) {
 849                 int r = loc_network_tree_node_new(node->ctx, n);
 850                 if (r)
 851                         return NULL;
 852         }
 853
 854         return *n;
 855 }
 856
 857 static struct loc_network_tree_node* loc_network_tree_get_path(struct loc_network_tree* tree, const struct in6_addr* address, unsigned int prefix) {
 858         struct loc_network_tree_node* node = tree->root;
 859
 860         for (unsigned int i = 0; i < prefix; i++) {
 861                 // Check if the ith bit is one or zero
 862                 node = loc_network_tree_get_node(node, in6_addr_get_bit(address, i));
 863         }
 864
 865         return node;
 866 }
 867
 868 static int __loc_network_tree_walk(struct loc_ctx* ctx, struct loc_network_tree_node* node,
 869                 int(*filter_callback)(struct loc_network* network, void* data),
 870                 int(*callback)(struct loc_network* network, void* data), void* data) {
 871         int r;
 872
 873         // Finding a network ends the walk here
 874         if (node->network) {
 875                 if (filter_callback) {
 876                         int f = filter_callback(node->network, data);
 877                         if (f < 0)
 878                                 return f;
 879
 880                         // Skip network if filter function returns value greater than zero
 881                         if (f > 0)
 882                                 return 0;
 883                 }
 884
 885                 r = callback(node->network, data);
 886                 if (r)
 887                         return r;
 888         }
 889
 890         // Walk down on the left side of the tree first
 891         if (node->zero) {
 892                 r = __loc_network_tree_walk(ctx, node->zero, filter_callback, callback, data);
 893                 if (r)
 894                         return r;
 895         }
 896
 897         // Then walk on the other side
 898         if (node->one) {
 899                 r = __loc_network_tree_walk(ctx, node->one, filter_callback, callback, data);
 900                 if (r)
 901                         return r;
 902         }
 903
 904         return 0;
 905 }
 906
 907 int loc_network_tree_walk(struct loc_network_tree* tree,
 908                 int(*filter_callback)(struct loc_network* network, void* data),
 909                 int(*callback)(struct loc_network* network, void* data), void* data) {
 910         return __loc_network_tree_walk(tree->ctx, tree->root, filter_callback, callback, data);
 911 }
 912
 913 static void loc_network_tree_free(struct loc_network_tree* tree) {
 914         DEBUG(tree->ctx, "Releasing network tree at %p\n", tree);
 915
 916         loc_network_tree_node_unref(tree->root);
 917
 918         loc_unref(tree->ctx);
 919         free(tree);
 920 }
 921
 922 struct loc_network_tree* loc_network_tree_unref(struct loc_network_tree* tree) {
 923         if (--tree->refcount > 0)
 924                 return tree;
 925
 926         loc_network_tree_free(tree);
 927         return NULL;
 928 }
 929
 930 static int __loc_network_tree_dump(struct loc_network* network, void* data) {
 931         DEBUG(network->ctx, "Dumping network at %p\n", network);
 932
 933         char* s = loc_network_str(network);
 934         if (!s)
 935                 return 1;
 936
 937         INFO(network->ctx, "%s\n", s);
 938         free(s);
 939
 940         return 0;
 941 }
 942
 943 int loc_network_tree_dump(struct loc_network_tree* tree) {
 944         DEBUG(tree->ctx, "Dumping network tree at %p\n", tree);
 945
 946         return loc_network_tree_walk(tree, NULL, __loc_network_tree_dump, NULL);
 947 }
 948
 949 int loc_network_tree_add_network(struct loc_network_tree* tree, struct loc_network* network) {
 950         DEBUG(tree->ctx, "Adding network %p to tree %p\n", network, tree);
 951
 952         struct loc_network_tree_node* node = loc_network_tree_get_path(tree,
 953                         &network->first_address, network->prefix);
 954         if (!node) {
 955                 ERROR(tree->ctx, "Could not find a node\n");
 956                 return -ENOMEM;
 957         }
 958
 959         // Check if node has not been set before
 960         if (node->network) {
 961                 DEBUG(tree->ctx, "There is already a network at this path\n");
 962                 return -EBUSY;
 963         }
 964
 965         // Point node to the network
 966         node->network = loc_network_ref(network);
 967
 968         return 0;
 969 }
 970
 971 static int __loc_network_tree_count(struct loc_network* network, void* data) {
 972         size_t* counter = (size_t*)data;
 973
 974         // Increase the counter for each network
 975         counter++;
 976
 977         return 0;
 978 }
 979
 980 size_t loc_network_tree_count_networks(struct loc_network_tree* tree) {
 981         size_t counter = 0;
 982
 983         int r = loc_network_tree_walk(tree, NULL, __loc_network_tree_count, &counter);
 984         if (r)
 985                 return r;
 986
 987         return counter;
 988 }
 989
 990 static size_t __loc_network_tree_count_nodes(struct loc_network_tree_node* node) {
 991         size_t counter = 1;
 992
 993         if (node->zero)
 994                 counter += __loc_network_tree_count_nodes(node->zero);
 995
 996         if (node->one)
 997                 counter += __loc_network_tree_count_nodes(node->one);
 998
 999         return counter;
1000 }
1001
1002 size_t loc_network_tree_count_nodes(struct loc_network_tree* tree) {
1003         return __loc_network_tree_count_nodes(tree->root);
1004 }
1005
1006 int loc_network_tree_node_new(struct loc_ctx* ctx, struct loc_network_tree_node** node) {
1007         struct loc_network_tree_node* n = calloc(1, sizeof(*n));
1008         if (!n)
1009                 return -ENOMEM;
1010
1011         n->ctx = loc_ref(ctx);
1012         n->refcount = 1;
1013
1014         n->zero = n->one = NULL;
1015
1016         DEBUG(n->ctx, "Network node allocated at %p\n", n);
1017         *node = n;
1018         return 0;
1019 }
1020
1021 struct loc_network_tree_node* loc_network_tree_node_ref(struct loc_network_tree_node* node) {
1022         if (node)
1023                 node->refcount++;
1024
1025         return node;
1026 }
1027
1028 static void loc_network_tree_node_free(struct loc_network_tree_node* node) {
1029         DEBUG(node->ctx, "Releasing network node at %p\n", node);
1030
1031         if (node->network)
1032                 loc_network_unref(node->network);
1033
1034         if (node->zero)
1035                 loc_network_tree_node_unref(node->zero);
1036
1037         if (node->one)
1038                 loc_network_tree_node_unref(node->one);
1039
1040         loc_unref(node->ctx);
1041         free(node);
1042 }
1043
1044 struct loc_network_tree_node* loc_network_tree_node_unref(struct loc_network_tree_node* node) {
1045         if (!node)
1046                 return NULL;
1047
1048         if (--node->refcount > 0)
1049                 return node;
1050
1051         loc_network_tree_node_free(node);
1052         return NULL;
1053 }
1054
1055 struct loc_network_tree_node* loc_network_tree_node_get(struct loc_network_tree_node* node, unsigned int index) {
1056         if (index == 0)
1057                 node = node->zero;
1058         else
1059                 node = node->one;
1060
1061         if (!node)
1062                 return NULL;
1063
1064         return loc_network_tree_node_ref(node);
1065 }
1066
1067 int loc_network_tree_node_is_leaf(struct loc_network_tree_node* node) {
1068         return (!!node->network);
1069 }
1070
1071 struct loc_network* loc_network_tree_node_get_network(struct loc_network_tree_node* node) {
1072         return loc_network_ref(node->network);
1073 }