src/database.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 <ctype.h>
  19 #include <errno.h>
  20 #include <netinet/in.h>
  21 #include <stddef.h>
  22 #include <stdint.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <sys/mman.h>
  27 #include <sys/types.h>
  28 #include <time.h>
  29 #include <unistd.h>
  30
  31 #ifdef HAVE_ENDIAN_H
  32 #  include <endian.h>
  33 #endif
  34
  35 #include <openssl/err.h>
  36 #include <openssl/evp.h>
  37 #include <openssl/pem.h>
  38
  39 #include <loc/libloc.h>
  40 #include <loc/as.h>
  41 #include <loc/as-list.h>
  42 #include <loc/compat.h>
  43 #include <loc/country.h>
  44 #include <loc/country-list.h>
  45 #include <loc/database.h>
  46 #include <loc/format.h>
  47 #include <loc/network.h>
  48 #include <loc/private.h>
  49 #include <loc/stringpool.h>
  50
  51 struct loc_database {
  52         struct loc_ctx* ctx;
  53         int refcount;
  54
  55         FILE* f;
  56
  57         enum loc_database_version version;
  58         time_t created_at;
  59         off_t vendor;
  60         off_t description;
  61         off_t license;
  62
  63         // Signatures
  64         char* signature1;
  65         size_t signature1_length;
  66         char* signature2;
  67         size_t signature2_length;
  68
  69         // ASes in the database
  70         struct loc_database_as_v1* as_v1;
  71         size_t as_count;
  72
  73         // Network tree
  74         struct loc_database_network_node_v1* network_nodes_v1;
  75         size_t network_nodes_count;
  76
  77         // Networks
  78         struct loc_database_network_v1* networks_v1;
  79         size_t networks_count;
  80
  81         // Countries
  82         struct loc_database_country_v1* countries_v1;
  83         size_t countries_count;
  84
  85         struct loc_stringpool* pool;
  86 };
  87
  88 #define MAX_STACK_DEPTH 256
  89
  90 struct loc_node_stack {
  91         off_t offset;
  92         int i; // Is this node 0 or 1?
  93         int depth;
  94 };
  95
  96 struct loc_database_enumerator {
  97         struct loc_ctx* ctx;
  98         struct loc_database* db;
  99         enum loc_database_enumerator_mode mode;
 100         int refcount;
 101
 102         // Search string
 103         char* string;
 104         struct loc_country_list* countries;
 105         struct loc_as_list* asns;
 106         enum loc_network_flags flags;
 107         int family;
 108
 109         // Flatten output?
 110         int flatten;
 111
 112         // Index of the AS we are looking at
 113         unsigned int as_index;
 114
 115         // Index of the country we are looking at
 116         unsigned int country_index;
 117
 118         // Network state
 119         struct in6_addr network_address;
 120         struct loc_node_stack network_stack[MAX_STACK_DEPTH];
 121         int network_stack_depth;
 122         unsigned int* networks_visited;
 123
 124         // For subnet search
 125         struct loc_network_list* stack;
 126 };
 127
 128 static int loc_database_read_magic(struct loc_database* db) {
 129         struct loc_database_magic magic;
 130
 131         // Read from file
 132         size_t bytes_read = fread(&magic, 1, sizeof(magic), db->f);
 133
 134         // Check if we have been able to read enough data
 135         if (bytes_read < sizeof(magic)) {
 136                 ERROR(db->ctx, "Could not read enough data to validate magic bytes\n");
 137                 DEBUG(db->ctx, "Read %zu bytes, but needed %zu\n", bytes_read, sizeof(magic));
 138                 return -ENOMSG;
 139         }
 140
 141         // Compare magic bytes
 142         if (memcmp(LOC_DATABASE_MAGIC, magic.magic, strlen(LOC_DATABASE_MAGIC)) == 0) {
 143                 DEBUG(db->ctx, "Magic value matches\n");
 144
 145                 // Parse version
 146                 db->version = magic.version;
 147
 148                 return 0;
 149         }
 150
 151         ERROR(db->ctx, "Unrecognized file type\n");
 152
 153         // Return an error
 154         return 1;
 155 }
 156
 157 static int loc_database_read_as_section_v1(struct loc_database* db,
 158                 const struct loc_database_header_v1* header) {
 159         off_t as_offset  = be32toh(header->as_offset);
 160         size_t as_length = be32toh(header->as_length);
 161
 162         DEBUG(db->ctx, "Reading AS section from %jd (%zu bytes)\n", (intmax_t)as_offset, as_length);
 163
 164         if (as_length > 0) {
 165                 db->as_v1 = mmap(NULL, as_length, PROT_READ,
 166                         MAP_SHARED, fileno(db->f), as_offset);
 167
 168                 if (db->as_v1 == MAP_FAILED)
 169                         return -errno;
 170         }
 171
 172         db->as_count = as_length / sizeof(*db->as_v1);
 173
 174         INFO(db->ctx, "Read %zu ASes from the database\n", db->as_count);
 175
 176         return 0;
 177 }
 178
 179 static int loc_database_read_network_nodes_section_v1(struct loc_database* db,
 180                 const struct loc_database_header_v1* header) {
 181         off_t network_nodes_offset  = be32toh(header->network_tree_offset);
 182         size_t network_nodes_length = be32toh(header->network_tree_length);
 183
 184         DEBUG(db->ctx, "Reading network nodes section from %jd (%zu bytes)\n",
 185                 (intmax_t)network_nodes_offset, network_nodes_length);
 186
 187         if (network_nodes_length > 0) {
 188                 db->network_nodes_v1 = mmap(NULL, network_nodes_length, PROT_READ,
 189                         MAP_SHARED, fileno(db->f), network_nodes_offset);
 190
 191                 if (db->network_nodes_v1 == MAP_FAILED)
 192                         return -errno;
 193         }
 194
 195         db->network_nodes_count = network_nodes_length / sizeof(*db->network_nodes_v1);
 196
 197         INFO(db->ctx, "Read %zu network nodes from the database\n", db->network_nodes_count);
 198
 199         return 0;
 200 }
 201
 202 static int loc_database_read_networks_section_v1(struct loc_database* db,
 203                 const struct loc_database_header_v1* header) {
 204         off_t networks_offset  = be32toh(header->network_data_offset);
 205         size_t networks_length = be32toh(header->network_data_length);
 206
 207         DEBUG(db->ctx, "Reading networks section from %jd (%zu bytes)\n",
 208                 (intmax_t)networks_offset, networks_length);
 209
 210         if (networks_length > 0) {
 211                 db->networks_v1 = mmap(NULL, networks_length, PROT_READ,
 212                         MAP_SHARED, fileno(db->f), networks_offset);
 213
 214                 if (db->networks_v1 == MAP_FAILED)
 215                         return -errno;
 216         }
 217
 218         db->networks_count = networks_length / sizeof(*db->networks_v1);
 219
 220         INFO(db->ctx, "Read %zu networks from the database\n", db->networks_count);
 221
 222         return 0;
 223 }
 224
 225 static int loc_database_read_countries_section_v1(struct loc_database* db,
 226                 const struct loc_database_header_v1* header) {
 227         off_t countries_offset  = be32toh(header->countries_offset);
 228         size_t countries_length = be32toh(header->countries_length);
 229
 230         DEBUG(db->ctx, "Reading countries section from %jd (%zu bytes)\n",
 231                 (intmax_t)countries_offset, countries_length);
 232
 233         if (countries_length > 0) {
 234                 db->countries_v1 = mmap(NULL, countries_length, PROT_READ,
 235                         MAP_SHARED, fileno(db->f), countries_offset);
 236
 237                 if (db->countries_v1 == MAP_FAILED)
 238                         return -errno;
 239         }
 240
 241         db->countries_count = countries_length / sizeof(*db->countries_v1);
 242
 243         INFO(db->ctx, "Read %zu countries from the database\n",
 244                 db->countries_count);
 245
 246         return 0;
 247 }
 248
 249 static int loc_database_read_signature(struct loc_database* db,
 250                 char** dst, char* src, size_t length) {
 251         // Check for a plausible signature length
 252         if (length > LOC_SIGNATURE_MAX_LENGTH) {
 253                 ERROR(db->ctx, "Signature too long: %ld\n", length);
 254                 return -EINVAL;
 255         }
 256
 257         DEBUG(db->ctx, "Reading signature of %ld bytes\n", length);
 258
 259         // Allocate space
 260         *dst = malloc(length);
 261         if (!*dst)
 262                 return -ENOMEM;
 263
 264         // Copy payload
 265         memcpy(*dst, src, length);
 266
 267         return 0;
 268 }
 269
 270 static int loc_database_read_header_v1(struct loc_database* db) {
 271         struct loc_database_header_v1 header;
 272         int r;
 273
 274         // Read from file
 275         size_t size = fread(&header, 1, sizeof(header), db->f);
 276
 277         if (size < sizeof(header)) {
 278                 ERROR(db->ctx, "Could not read enough data for header\n");
 279                 return -ENOMSG;
 280         }
 281
 282         // Copy over data
 283         db->created_at  = be64toh(header.created_at);
 284         db->vendor      = be32toh(header.vendor);
 285         db->description = be32toh(header.description);
 286         db->license     = be32toh(header.license);
 287
 288         db->signature1_length = be16toh(header.signature1_length);
 289         db->signature2_length = be16toh(header.signature2_length);
 290
 291         // Read signatures
 292         if (db->signature1_length) {
 293                 r = loc_database_read_signature(db, &db->signature1,
 294                         header.signature1, db->signature1_length);
 295                 if (r)
 296                         return r;
 297         }
 298
 299         if (db->signature2_length) {
 300                 r = loc_database_read_signature(db, &db->signature2,
 301                         header.signature2, db->signature2_length);
 302                 if (r)
 303                         return r;
 304         }
 305
 306         // Open pool
 307         off_t pool_offset  = be32toh(header.pool_offset);
 308         size_t pool_length = be32toh(header.pool_length);
 309
 310         r = loc_stringpool_open(db->ctx, &db->pool,
 311                 db->f, pool_length, pool_offset);
 312         if (r)
 313                 return r;
 314
 315         // AS section
 316         r = loc_database_read_as_section_v1(db, &header);
 317         if (r)
 318                 return r;
 319
 320         // Network Nodes
 321         r = loc_database_read_network_nodes_section_v1(db, &header);
 322         if (r)
 323                 return r;
 324
 325         // Networks
 326         r = loc_database_read_networks_section_v1(db, &header);
 327         if (r)
 328                 return r;
 329
 330         // countries
 331         r = loc_database_read_countries_section_v1(db, &header);
 332         if (r)
 333                 return r;
 334
 335         return 0;
 336 }
 337
 338 static int loc_database_read_header(struct loc_database* db) {
 339         DEBUG(db->ctx, "Database version is %u\n", db->version);
 340
 341         switch (db->version) {
 342                 case LOC_DATABASE_VERSION_1:
 343                         return loc_database_read_header_v1(db);
 344
 345                 default:
 346                         ERROR(db->ctx, "Incompatible database version: %u\n", db->version);
 347                         return 1;
 348         }
 349 }
 350
 351 static int loc_database_read(struct loc_database* db, FILE* f) {
 352         clock_t start = clock();
 353
 354         int fd = fileno(f);
 355
 356         // Clone file descriptor
 357         fd = dup(fd);
 358         if (!fd) {
 359                 ERROR(db->ctx, "Could not duplicate file descriptor\n");
 360                 return -1;
 361         }
 362
 363         // Reopen the file so that we can keep our own file handle
 364         db->f = fdopen(fd, "r");
 365         if (!db->f) {
 366                 ERROR(db->ctx, "Could not re-open database file\n");
 367                 return -1;
 368         }
 369
 370         // Rewind to the start of the file
 371         rewind(db->f);
 372
 373         // Read magic bytes
 374         int r = loc_database_read_magic(db);
 375         if (r)
 376                 return r;
 377
 378         // Read the header
 379         r = loc_database_read_header(db);
 380         if (r)
 381                 return r;
 382
 383         clock_t end = clock();
 384
 385         INFO(db->ctx, "Opened database in %.4fms\n",
 386                 (double)(end - start) / CLOCKS_PER_SEC * 1000);
 387
 388         return 0;
 389 }
 390
 391 LOC_EXPORT int loc_database_new(struct loc_ctx* ctx, struct loc_database** database, FILE* f) {
 392         // Fail on invalid file handle
 393         if (!f)
 394                 return -EINVAL;
 395
 396         struct loc_database* db = calloc(1, sizeof(*db));
 397         if (!db)
 398                 return -ENOMEM;
 399
 400         // Reference context
 401         db->ctx = loc_ref(ctx);
 402         db->refcount = 1;
 403
 404         DEBUG(db->ctx, "Database object allocated at %p\n", db);
 405
 406         int r = loc_database_read(db, f);
 407         if (r) {
 408                 loc_database_unref(db);
 409                 return r;
 410         }
 411
 412         *database = db;
 413
 414         return 0;
 415 }
 416
 417 LOC_EXPORT struct loc_database* loc_database_ref(struct loc_database* db) {
 418         db->refcount++;
 419
 420         return db;
 421 }
 422
 423 static void loc_database_free(struct loc_database* db) {
 424         int r;
 425
 426         DEBUG(db->ctx, "Releasing database %p\n", db);
 427
 428         // Removing all ASes
 429         if (db->as_v1) {
 430                 r = munmap(db->as_v1, db->as_count * sizeof(*db->as_v1));
 431                 if (r)
 432                         ERROR(db->ctx, "Could not unmap AS section: %s\n", strerror(errno));
 433         }
 434
 435         // Remove mapped network sections
 436         if (db->networks_v1) {
 437                 r = munmap(db->networks_v1, db->networks_count * sizeof(*db->networks_v1));
 438                 if (r)
 439                         ERROR(db->ctx, "Could not unmap networks section: %s\n", strerror(errno));
 440         }
 441
 442         // Remove mapped network nodes section
 443         if (db->network_nodes_v1) {
 444                 r = munmap(db->network_nodes_v1, db->network_nodes_count * sizeof(*db->network_nodes_v1));
 445                 if (r)
 446                         ERROR(db->ctx, "Could not unmap network nodes section: %s\n", strerror(errno));
 447         }
 448
 449         if (db->pool)
 450                 loc_stringpool_unref(db->pool);
 451
 452         // Free signature
 453         if (db->signature1)
 454                 free(db->signature1);
 455         if (db->signature2)
 456                 free(db->signature2);
 457
 458         // Close database file
 459         if (db->f)
 460                 fclose(db->f);
 461
 462         loc_unref(db->ctx);
 463         free(db);
 464 }
 465
 466 LOC_EXPORT struct loc_database* loc_database_unref(struct loc_database* db) {
 467         if (--db->refcount > 0)
 468                 return NULL;
 469
 470         loc_database_free(db);
 471         return NULL;
 472 }
 473
 474 LOC_EXPORT int loc_database_verify(struct loc_database* db, FILE* f) {
 475         // Cannot do this when no signature is available
 476         if (!db->signature1 && !db->signature2) {
 477                 DEBUG(db->ctx, "No signature available to verify\n");
 478                 return 1;
 479         }
 480
 481         // Start the stopwatch
 482         clock_t start = clock();
 483
 484         // Load public key
 485         EVP_PKEY* pkey = PEM_read_PUBKEY(f, NULL, NULL, NULL);
 486         if (!pkey) {
 487                 char* error = ERR_error_string(ERR_get_error(), NULL);
 488                 ERROR(db->ctx, "Could not parse public key: %s\n", error);
 489
 490                 return -1;
 491         }
 492
 493         int r = 0;
 494
 495         EVP_MD_CTX* mdctx = EVP_MD_CTX_new();
 496
 497         // Initialise hash function
 498         r = EVP_DigestVerifyInit(mdctx, NULL, NULL, NULL, pkey);
 499         if (r != 1) {
 500                 ERROR(db->ctx, "Error initializing signature validation: %s\n",
 501                         ERR_error_string(ERR_get_error(), NULL));
 502                 r = 1;
 503
 504                 goto CLEANUP;
 505         }
 506
 507         // Reset file to start
 508         rewind(db->f);
 509
 510         // Read magic
 511         struct loc_database_magic magic;
 512         fread(&magic, 1, sizeof(magic), db->f);
 513
 514         hexdump(db->ctx, &magic, sizeof(magic));
 515
 516         // Feed magic into the hash
 517         r = EVP_DigestVerifyUpdate(mdctx, &magic, sizeof(magic));
 518         if (r != 1) {
 519                 ERROR(db->ctx, "%s\n", ERR_error_string(ERR_get_error(), NULL));
 520                 r = 1;
 521
 522                 goto CLEANUP;
 523         }
 524
 525         // Read the header
 526         struct loc_database_header_v1 header_v1;
 527         size_t bytes_read;
 528
 529         switch (db->version) {
 530                 case LOC_DATABASE_VERSION_1:
 531                         bytes_read = fread(&header_v1, 1, sizeof(header_v1), db->f);
 532                         if (bytes_read < sizeof(header_v1)) {
 533                                 ERROR(db->ctx, "Could not read header\n");
 534                                 r = 1;
 535
 536                                 goto CLEANUP;
 537                         }
 538
 539                         // Clear signatures
 540                         memset(header_v1.signature1, '\0', sizeof(header_v1.signature1));
 541                         header_v1.signature1_length = 0;
 542                         memset(header_v1.signature2, '\0', sizeof(header_v1.signature2));
 543                         header_v1.signature2_length = 0;
 544
 545                         hexdump(db->ctx, &header_v1, sizeof(header_v1));
 546
 547                         // Feed header into the hash
 548                         r = EVP_DigestVerifyUpdate(mdctx, &header_v1, sizeof(header_v1));
 549                         if (r != 1) {
 550                                 ERROR(db->ctx, "%s\n", ERR_error_string(ERR_get_error(), NULL));
 551                                 r = 1;
 552
 553                                 goto CLEANUP;
 554                         }
 555                         break;
 556
 557                 default:
 558                         ERROR(db->ctx, "Cannot compute hash for database with format %d\n",
 559                                 db->version);
 560                         r = -EINVAL;
 561                         goto CLEANUP;
 562         }
 563
 564         // Walk through the file in chunks of 64kB
 565         char buffer[64 * 1024];
 566
 567         while (!feof(db->f)) {
 568                 bytes_read = fread(buffer, 1, sizeof(buffer), db->f);
 569
 570                 hexdump(db->ctx, buffer, bytes_read);
 571
 572                 r = EVP_DigestVerifyUpdate(mdctx, buffer, bytes_read);
 573                 if (r != 1) {
 574                         ERROR(db->ctx, "%s\n", ERR_error_string(ERR_get_error(), NULL));
 575                         r = 1;
 576
 577                         goto CLEANUP;
 578                 }
 579         }
 580
 581         // Check first signature
 582         if (db->signature1) {
 583                 hexdump(db->ctx, db->signature1, db->signature1_length);
 584
 585                 r = EVP_DigestVerifyFinal(mdctx,
 586                         (unsigned char*)db->signature1, db->signature1_length);
 587
 588                 if (r == 0) {
 589                         DEBUG(db->ctx, "The first signature is invalid\n");
 590                         r = 1;
 591                 } else if (r == 1) {
 592                         DEBUG(db->ctx, "The first signature is valid\n");
 593                         r = 0;
 594                 } else {
 595                         ERROR(db->ctx, "Error verifying the first signature: %s\n",
 596                                 ERR_error_string(ERR_get_error(), NULL));
 597                         r = -1;
 598                 }
 599         }
 600
 601         // Check second signature only when the first one was invalid
 602         if (r && db->signature2) {
 603                 hexdump(db->ctx, db->signature2, db->signature2_length);
 604
 605                 r = EVP_DigestVerifyFinal(mdctx,
 606                         (unsigned char*)db->signature2, db->signature2_length);
 607
 608                 if (r == 0) {
 609                         DEBUG(db->ctx, "The second signature is invalid\n");
 610                         r = 1;
 611                 } else if (r == 1) {
 612                         DEBUG(db->ctx, "The second signature is valid\n");
 613                         r = 0;
 614                 } else {
 615                         ERROR(db->ctx, "Error verifying the second signature: %s\n",
 616                                 ERR_error_string(ERR_get_error(), NULL));
 617                         r = -1;
 618                 }
 619         }
 620
 621         clock_t end = clock();
 622         DEBUG(db->ctx, "Signature checked in %.4fms\n",
 623                 (double)(end - start) / CLOCKS_PER_SEC * 1000);
 624
 625 CLEANUP:
 626         // Cleanup
 627         EVP_MD_CTX_free(mdctx);
 628         EVP_PKEY_free(pkey);
 629
 630         return r;
 631 }
 632
 633 LOC_EXPORT time_t loc_database_created_at(struct loc_database* db) {
 634         return db->created_at;
 635 }
 636
 637 LOC_EXPORT const char* loc_database_get_vendor(struct loc_database* db) {
 638         return loc_stringpool_get(db->pool, db->vendor);
 639 }
 640
 641 LOC_EXPORT const char* loc_database_get_description(struct loc_database* db) {
 642         return loc_stringpool_get(db->pool, db->description);
 643 }
 644
 645 LOC_EXPORT const char* loc_database_get_license(struct loc_database* db) {
 646         return loc_stringpool_get(db->pool, db->license);
 647 }
 648
 649 LOC_EXPORT size_t loc_database_count_as(struct loc_database* db) {
 650         return db->as_count;
 651 }
 652
 653 // Returns the AS at position pos
 654 static int loc_database_fetch_as(struct loc_database* db, struct loc_as** as, off_t pos) {
 655         if ((size_t)pos >= db->as_count)
 656                 return -EINVAL;
 657
 658         DEBUG(db->ctx, "Fetching AS at position %jd\n", (intmax_t)pos);
 659
 660         int r;
 661         switch (db->version) {
 662                 case LOC_DATABASE_VERSION_1:
 663                         r = loc_as_new_from_database_v1(db->ctx, db->pool, as, db->as_v1 + pos);
 664                         break;
 665
 666                 default:
 667                         return -1;
 668         }
 669
 670         if (r == 0) {
 671                 DEBUG(db->ctx, "Got AS%u\n", loc_as_get_number(*as));
 672         }
 673
 674         return r;
 675 }
 676
 677 // Performs a binary search to find the AS in the list
 678 LOC_EXPORT int loc_database_get_as(struct loc_database* db, struct loc_as** as, uint32_t number) {
 679         off_t lo = 0;
 680         off_t hi = db->as_count - 1;
 681
 682         // Save start time
 683         clock_t start = clock();
 684
 685         while (lo <= hi) {
 686                 off_t i = (lo + hi) / 2;
 687
 688                 // Fetch AS in the middle between lo and hi
 689                 int r = loc_database_fetch_as(db, as, i);
 690                 if (r)
 691                         return r;
 692
 693                 // Check if this is a match
 694                 uint32_t as_number = loc_as_get_number(*as);
 695                 if (as_number == number) {
 696                         clock_t end = clock();
 697
 698                         // Log how fast this has been
 699                         DEBUG(db->ctx, "Found AS%u in %.4fms\n", as_number,
 700                                 (double)(end - start) / CLOCKS_PER_SEC * 1000);
 701
 702                         return 0;
 703                 }
 704
 705                 // If it wasn't, we release the AS and
 706                 // adjust our search pointers
 707                 loc_as_unref(*as);
 708
 709                 if (as_number < number) {
 710                         lo = i + 1;
 711                 } else
 712                         hi = i - 1;
 713         }
 714
 715         // Nothing found
 716         *as = NULL;
 717
 718         return 1;
 719 }
 720
 721 // Returns the network at position pos
 722 static int loc_database_fetch_network(struct loc_database* db, struct loc_network** network,
 723                 struct in6_addr* address, unsigned int prefix, off_t pos) {
 724         if ((size_t)pos >= db->networks_count) {
 725                 DEBUG(db->ctx, "Network ID out of range: %jd/%jd\n",
 726                         (intmax_t)pos, (intmax_t)db->networks_count);
 727                 return -EINVAL;
 728         }
 729
 730
 731         DEBUG(db->ctx, "Fetching network at position %jd\n", (intmax_t)pos);
 732
 733         int r;
 734         switch (db->version) {
 735                 case LOC_DATABASE_VERSION_1:
 736                         r = loc_network_new_from_database_v1(db->ctx, network,
 737                                 address, prefix, db->networks_v1 + pos);
 738                         break;
 739
 740                 default:
 741                         return -1;
 742         }
 743
 744         if (r == 0) {
 745                 char* string = loc_network_str(*network);
 746                 DEBUG(db->ctx, "Got network %s\n", string);
 747                 free(string);
 748         }
 749
 750         return r;
 751 }
 752
 753 static int __loc_database_node_is_leaf(const struct loc_database_network_node_v1* node) {
 754         return (node->network != htobe32(0xffffffff));
 755 }
 756
 757 static int __loc_database_lookup_handle_leaf(struct loc_database* db, const struct in6_addr* address,
 758                 struct loc_network** network, struct in6_addr* network_address, unsigned int prefix,
 759                 const struct loc_database_network_node_v1* node) {
 760         off_t network_index = be32toh(node->network);
 761
 762         DEBUG(db->ctx, "Handling leaf node at %jd (%jd)\n", (intmax_t)(node - db->network_nodes_v1), (intmax_t)network_index);
 763
 764         // Fetch the network
 765         int r = loc_database_fetch_network(db, network,
 766                 network_address, prefix, network_index);
 767         if (r) {
 768                 ERROR(db->ctx, "Could not fetch network %jd from database\n", (intmax_t)network_index);
 769                 return r;
 770         }
 771
 772         // Check if the given IP address is inside the network
 773         r = loc_network_match_address(*network, address);
 774         if (r) {
 775                 DEBUG(db->ctx, "Searched address is not part of the network\n");
 776
 777                 loc_network_unref(*network);
 778                 *network = NULL;
 779                 return 1;
 780         }
 781
 782         // A network was found and the IP address matches
 783         return 0;
 784 }
 785
 786 // Searches for an exact match along the path
 787 static int __loc_database_lookup(struct loc_database* db, const struct in6_addr* address,
 788                 struct loc_network** network, struct in6_addr* network_address,
 789                 const struct loc_database_network_node_v1* node, unsigned int level) {
 790         int r;
 791         off_t node_index;
 792
 793         // Follow the path
 794         int bit = in6_addr_get_bit(address, level);
 795         in6_addr_set_bit(network_address, level, bit);
 796
 797         if (bit == 0)
 798                 node_index = be32toh(node->zero);
 799         else
 800                 node_index = be32toh(node->one);
 801
 802         // If the node index is zero, the tree ends here
 803         // and we cannot descend any further
 804         if (node_index > 0) {
 805                 // Check boundaries
 806                 if ((size_t)node_index >= db->network_nodes_count)
 807                         return -EINVAL;
 808
 809                 // Move on to the next node
 810                 r = __loc_database_lookup(db, address, network, network_address,
 811                         db->network_nodes_v1 + node_index, level + 1);
 812
 813                 // End here if a result was found
 814                 if (r == 0)
 815                         return r;
 816
 817                 // Raise any errors
 818                 else if (r < 0)
 819                         return r;
 820
 821                 DEBUG(db->ctx, "No match found below level %u\n", level);
 822         } else {
 823                 DEBUG(db->ctx, "Tree ended at level %u\n", level);
 824         }
 825
 826         // If this node has a leaf, we will check if it matches
 827         if (__loc_database_node_is_leaf(node)) {
 828                 r = __loc_database_lookup_handle_leaf(db, address, network, network_address, level, node);
 829                 if (r <= 0)
 830                         return r;
 831         }
 832
 833         return 1;
 834 }
 835
 836 LOC_EXPORT int loc_database_lookup(struct loc_database* db,
 837                 struct in6_addr* address, struct loc_network** network) {
 838         struct in6_addr network_address;
 839         memset(&network_address, 0, sizeof(network_address));
 840
 841         *network = NULL;
 842
 843         // Save start time
 844         clock_t start = clock();
 845
 846         int r = __loc_database_lookup(db, address, network, &network_address,
 847                 db->network_nodes_v1, 0);
 848
 849         clock_t end = clock();
 850
 851         // Log how fast this has been
 852         DEBUG(db->ctx, "Executed network search in %.4fms\n",
 853                 (double)(end - start) / CLOCKS_PER_SEC * 1000);
 854
 855         return r;
 856 }
 857
 858 LOC_EXPORT int loc_database_lookup_from_string(struct loc_database* db,
 859                 const char* string, struct loc_network** network) {
 860         struct in6_addr address;
 861
 862         int r = loc_parse_address(db->ctx, string, &address);
 863         if (r)
 864                 return r;
 865
 866         return loc_database_lookup(db, &address, network);
 867 }
 868
 869 // Returns the country at position pos
 870 static int loc_database_fetch_country(struct loc_database* db,
 871                 struct loc_country** country, off_t pos) {
 872         if ((size_t)pos >= db->countries_count)
 873                 return -EINVAL;
 874
 875         DEBUG(db->ctx, "Fetching country at position %jd\n", (intmax_t)pos);
 876
 877         int r;
 878         switch (db->version) {
 879                 case LOC_DATABASE_VERSION_1:
 880                         r = loc_country_new_from_database_v1(db->ctx, db->pool, country, db->countries_v1 + pos);
 881                         break;
 882
 883                 default:
 884                         return -1;
 885         }
 886
 887         if (r == 0) {
 888                 DEBUG(db->ctx, "Got country %s\n", loc_country_get_code(*country));
 889         }
 890
 891         return r;
 892 }
 893
 894 // Performs a binary search to find the country in the list
 895 LOC_EXPORT int loc_database_get_country(struct loc_database* db,
 896                 struct loc_country** country, const char* code) {
 897         off_t lo = 0;
 898         off_t hi = db->countries_count - 1;
 899
 900         // Save start time
 901         clock_t start = clock();
 902
 903         while (lo <= hi) {
 904                 off_t i = (lo + hi) / 2;
 905
 906                 // Fetch country in the middle between lo and hi
 907                 int r = loc_database_fetch_country(db, country, i);
 908                 if (r)
 909                         return r;
 910
 911                 // Check if this is a match
 912                 const char* cc = loc_country_get_code(*country);
 913                 int result = strcmp(code, cc);
 914
 915                 if (result == 0) {
 916                         clock_t end = clock();
 917
 918                         // Log how fast this has been
 919                         DEBUG(db->ctx, "Found country %s in %.4fms\n", cc,
 920                                 (double)(end - start) / CLOCKS_PER_SEC * 1000);
 921
 922                         return 0;
 923                 }
 924
 925                 // If it wasn't, we release the country and
 926                 // adjust our search pointers
 927                 loc_country_unref(*country);
 928
 929                 if (result > 0) {
 930                         lo = i + 1;
 931                 } else
 932                         hi = i - 1;
 933         }
 934
 935         // Nothing found
 936         *country = NULL;
 937
 938         return 1;
 939 }
 940
 941 // Enumerator
 942
 943 static void loc_database_enumerator_free(struct loc_database_enumerator* enumerator) {
 944         DEBUG(enumerator->ctx, "Releasing database enumerator %p\n", enumerator);
 945
 946         // Release all references
 947         loc_database_unref(enumerator->db);
 948         loc_unref(enumerator->ctx);
 949
 950         if (enumerator->string)
 951                 free(enumerator->string);
 952
 953         if (enumerator->countries)
 954                 loc_country_list_unref(enumerator->countries);
 955
 956         if (enumerator->asns)
 957                 loc_as_list_unref(enumerator->asns);
 958
 959         // Free network search
 960         free(enumerator->networks_visited);
 961
 962         // Free subnet stack
 963         if (enumerator->stack)
 964                 loc_network_list_unref(enumerator->stack);
 965
 966         free(enumerator);
 967 }
 968
 969 LOC_EXPORT int loc_database_enumerator_new(struct loc_database_enumerator** enumerator,
 970                 struct loc_database* db, enum loc_database_enumerator_mode mode, int flags) {
 971         struct loc_database_enumerator* e = calloc(1, sizeof(*e));
 972         if (!e)
 973                 return -ENOMEM;
 974
 975         // Reference context
 976         e->ctx = loc_ref(db->ctx);
 977         e->db = loc_database_ref(db);
 978         e->mode = mode;
 979         e->refcount = 1;
 980
 981         // Flatten output?
 982         e->flatten = (flags & LOC_DB_ENUMERATOR_FLAGS_FLATTEN);
 983
 984         // Initialise graph search
 985         e->network_stack_depth = 1;
 986         e->networks_visited = calloc(db->network_nodes_count, sizeof(*e->networks_visited));
 987
 988         // Allocate stack
 989         int r = loc_network_list_new(e->ctx, &e->stack);
 990         if (r) {
 991                 loc_database_enumerator_free(e);
 992                 return r;
 993         }
 994
 995         DEBUG(e->ctx, "Database enumerator object allocated at %p\n", e);
 996
 997         *enumerator = e;
 998         return 0;
 999 }
1000
1001 LOC_EXPORT struct loc_database_enumerator* loc_database_enumerator_ref(struct loc_database_enumerator* enumerator) {
1002         enumerator->refcount++;
1003
1004         return enumerator;
1005 }
1006
1007 LOC_EXPORT struct loc_database_enumerator* loc_database_enumerator_unref(struct loc_database_enumerator* enumerator) {
1008         if (!enumerator)
1009                 return NULL;
1010
1011         if (--enumerator->refcount > 0)
1012                 return enumerator;
1013
1014         loc_database_enumerator_free(enumerator);
1015         return NULL;
1016 }
1017
1018 LOC_EXPORT int loc_database_enumerator_set_string(struct loc_database_enumerator* enumerator, const char* string) {
1019         enumerator->string = strdup(string);
1020
1021         // Make the string lowercase
1022         for (char *p = enumerator->string; *p; p++)
1023                 *p = tolower(*p);
1024
1025         return 0;
1026 }
1027
1028 LOC_EXPORT struct loc_country_list* loc_database_enumerator_get_countries(
1029                 struct loc_database_enumerator* enumerator) {
1030         if (!enumerator->countries)
1031                 return NULL;
1032
1033         return loc_country_list_ref(enumerator->countries);
1034 }
1035
1036 LOC_EXPORT int loc_database_enumerator_set_countries(
1037                 struct loc_database_enumerator* enumerator, struct loc_country_list* countries) {
1038         if (enumerator->countries)
1039                 loc_country_list_unref(enumerator->countries);
1040
1041         enumerator->countries = loc_country_list_ref(countries);
1042
1043         return 0;
1044 }
1045
1046 LOC_EXPORT struct loc_as_list* loc_database_enumerator_get_asns(
1047                 struct loc_database_enumerator* enumerator) {
1048         if (!enumerator->asns)
1049                 return NULL;
1050
1051         return loc_as_list_ref(enumerator->asns);
1052 }
1053
1054 LOC_EXPORT int loc_database_enumerator_set_asns(
1055                 struct loc_database_enumerator* enumerator, struct loc_as_list* asns) {
1056         if (enumerator->asns)
1057                 loc_as_list_unref(enumerator->asns);
1058
1059         enumerator->asns = loc_as_list_ref(asns);
1060
1061         return 0;
1062 }
1063
1064 LOC_EXPORT int loc_database_enumerator_set_flag(
1065                 struct loc_database_enumerator* enumerator, enum loc_network_flags flag) {
1066         enumerator->flags |= flag;
1067
1068         return 0;
1069 }
1070
1071 LOC_EXPORT int loc_database_enumerator_set_family(
1072                 struct loc_database_enumerator* enumerator, int family) {
1073         enumerator->family = family;
1074
1075         return 0;
1076 }
1077
1078 LOC_EXPORT int loc_database_enumerator_next_as(
1079                 struct loc_database_enumerator* enumerator, struct loc_as** as) {
1080         *as = NULL;
1081
1082         // Do not do anything if not in AS mode
1083         if (enumerator->mode != LOC_DB_ENUMERATE_ASES)
1084                 return 0;
1085
1086         struct loc_database* db = enumerator->db;
1087
1088         while (enumerator->as_index < db->as_count) {
1089                 // Fetch the next AS
1090                 int r = loc_database_fetch_as(db, as, enumerator->as_index++);
1091                 if (r)
1092                         return r;
1093
1094                 r = loc_as_match_string(*as, enumerator->string);
1095                 if (r == 1) {
1096                         DEBUG(enumerator->ctx, "AS%d (%s) matches %s\n",
1097                                 loc_as_get_number(*as), loc_as_get_name(*as), enumerator->string);
1098
1099                         return 0;
1100                 }
1101
1102                 // No match
1103                 loc_as_unref(*as);
1104                 *as = NULL;
1105         }
1106
1107         // Reset the index
1108         enumerator->as_index = 0;
1109
1110         // We have searched through all of them
1111         return 0;
1112 }
1113
1114 static int loc_database_enumerator_stack_push_node(
1115                 struct loc_database_enumerator* e, off_t offset, int i, int depth) {
1116         // Do not add empty nodes
1117         if (!offset)
1118                 return 0;
1119
1120         // Check if there is any space left on the stack
1121         if (e->network_stack_depth >= MAX_STACK_DEPTH) {
1122                 ERROR(e->ctx, "Maximum stack size reached: %d\n", e->network_stack_depth);
1123                 return -1;
1124         }
1125
1126         // Increase stack size
1127         int s = ++e->network_stack_depth;
1128
1129         DEBUG(e->ctx, "Added node %jd to stack (%d)\n", (intmax_t)offset, depth);
1130
1131         e->network_stack[s].offset = offset;
1132         e->network_stack[s].i = i;
1133         e->network_stack[s].depth = depth;
1134
1135         return 0;
1136 }
1137
1138 static int loc_database_enumerator_filter_network(
1139                 struct loc_database_enumerator* enumerator, struct loc_network* network) {
1140         // Skip if the family does not match
1141         if (enumerator->family && loc_network_address_family(network) != enumerator->family)
1142                 return 1;
1143
1144         // Skip if the country code does not match
1145         if (enumerator->countries) {
1146                 if (!loc_country_list_empty(enumerator->countries)) {
1147                         const char* country_code = loc_network_get_country_code(network);
1148
1149                         if (!loc_country_list_contains_code(enumerator->countries, country_code))
1150                                 return 1;
1151                 }
1152         }
1153
1154         // Skip if the ASN does not match
1155         if (enumerator->asns) {
1156                 if (!loc_as_list_empty(enumerator->asns)) {
1157                         uint32_t asn = loc_network_get_asn(network);
1158
1159                         if (!loc_as_list_contains_number(enumerator->asns, asn))
1160                                 return 1;
1161                 }
1162         }
1163
1164         // Skip if flags do not match
1165         if (enumerator->flags &&
1166                         !loc_network_match_flag(network, enumerator->flags))
1167                 return 1;
1168
1169         // Do not filter
1170         return 0;
1171 }
1172
1173 static int __loc_database_enumerator_next_network(
1174                 struct loc_database_enumerator* enumerator, struct loc_network** network, int filter) {
1175         // Return top element from the stack
1176         while (1) {
1177                 *network = loc_network_list_pop(enumerator->stack);
1178
1179                 // Stack is empty
1180                 if (!*network)
1181                         break;
1182
1183                 // Throw away any networks by filter
1184                 if (filter && loc_database_enumerator_filter_network(enumerator, *network)) {
1185                         loc_network_unref(*network);
1186                         *network = NULL;
1187                         continue;
1188                 }
1189
1190                 // Return result
1191                 return 0;
1192         }
1193
1194         DEBUG(enumerator->ctx, "Called with a stack of %u nodes\n",
1195                 enumerator->network_stack_depth);
1196
1197         // Perform DFS
1198         while (enumerator->network_stack_depth > 0) {
1199                 DEBUG(enumerator->ctx, "Stack depth: %u\n", enumerator->network_stack_depth);
1200
1201                 // Get object from top of the stack
1202                 struct loc_node_stack* node = &enumerator->network_stack[enumerator->network_stack_depth];
1203
1204                 // Remove the node from the stack if we have already visited it
1205                 if (enumerator->networks_visited[node->offset]) {
1206                         enumerator->network_stack_depth--;
1207                         continue;
1208                 }
1209
1210                 // Mark the bits on the path correctly
1211                 in6_addr_set_bit(&enumerator->network_address,
1212                         (node->depth > 0) ? node->depth - 1 : 0, node->i);
1213
1214                 DEBUG(enumerator->ctx, "Looking at node %jd\n", (intmax_t)node->offset);
1215                 enumerator->networks_visited[node->offset]++;
1216
1217                 // Pop node from top of the stack
1218                 struct loc_database_network_node_v1* n =
1219                         enumerator->db->network_nodes_v1 + node->offset;
1220
1221                 // Add edges to stack
1222                 int r = loc_database_enumerator_stack_push_node(enumerator,
1223                         be32toh(n->one), 1, node->depth + 1);
1224
1225                 if (r)
1226                         return r;
1227
1228                 r = loc_database_enumerator_stack_push_node(enumerator,
1229                         be32toh(n->zero), 0, node->depth + 1);
1230
1231                 if (r)
1232                         return r;
1233
1234                 // Check if this node is a leaf and has a network object
1235                 if (__loc_database_node_is_leaf(n)) {
1236                         off_t network_index = be32toh(n->network);
1237
1238                         DEBUG(enumerator->ctx, "Node has a network at %jd\n", (intmax_t)network_index);
1239
1240                         // Fetch the network object
1241                         r = loc_database_fetch_network(enumerator->db, network,
1242                                 &enumerator->network_address, node->depth, network_index);
1243
1244                         // Break on any errors
1245                         if (r)
1246                                 return r;
1247
1248                         // Return all networks when the filter is disabled
1249                         if (!filter)
1250                                 return 0;
1251
1252                         // Check if we are interested in this network
1253                         if (loc_database_enumerator_filter_network(enumerator, *network)) {
1254                                 loc_network_unref(*network);
1255                                 *network = NULL;
1256
1257                                 continue;
1258                         }
1259
1260                         return 0;
1261                 }
1262         }
1263
1264         // Reached the end of the search
1265         return 0;
1266 }
1267
1268 static int __loc_database_enumerator_next_network_flattened(
1269                 struct loc_database_enumerator* enumerator, struct loc_network** network) {
1270         // Fetch the next network
1271         int r = __loc_database_enumerator_next_network(enumerator, network, 1);
1272         if (r)
1273                 return r;
1274
1275         // End if we could not read another network
1276         if (!*network)
1277                 return 0;
1278
1279         struct loc_network* subnet = NULL;
1280         struct loc_network_list* subnets;
1281
1282         // Create a list with all subnets
1283         r = loc_network_list_new(enumerator->ctx, &subnets);
1284         if (r)
1285                 return r;
1286
1287         // Search all subnets from the database
1288         while (1) {
1289                 // Fetch the next network in line
1290                 r = __loc_database_enumerator_next_network(enumerator, &subnet, 0);
1291                 if (r)
1292                         goto END;
1293
1294                 // End if we did not receive another subnet
1295                 if (!subnet)
1296                         break;
1297
1298                 // Collect all subnets in a list
1299                 if (loc_network_is_subnet(*network, subnet)) {
1300                         r = loc_network_list_push(subnets, subnet);
1301                         if (r)
1302                                 goto END;
1303
1304                         loc_network_unref(subnet);
1305                         continue;
1306                 }
1307
1308                 // If this is not a subnet, we push it back onto the stack and break
1309                 r = loc_network_list_push(enumerator->stack, subnet);
1310                 if (r)
1311                         goto END;
1312
1313                 loc_network_unref(subnet);
1314                 break;
1315         }
1316
1317         DEBUG(enumerator->ctx, "Found %zu subnet(s)\n", loc_network_list_size(subnets));
1318
1319         // We can abort here if the network has no subnets
1320         if (loc_network_list_empty(subnets)) {
1321                 loc_network_list_unref(subnets);
1322
1323                 return 0;
1324         }
1325
1326         // If the network has any subnets, we will break it into smaller parts
1327         // without the subnets.
1328         struct loc_network_list* excluded = loc_network_exclude_list(*network, subnets);
1329         if (!excluded || loc_network_list_empty(excluded)) {
1330                 r = 1;
1331                 goto END;
1332         }
1333
1334         // Replace network with the first one
1335         loc_network_unref(*network);
1336
1337         *network = loc_network_list_pop_first(excluded);
1338
1339         // Push the rest onto the stack
1340         loc_network_list_reverse(excluded);
1341         loc_network_list_merge(enumerator->stack, excluded);
1342
1343         loc_network_list_unref(excluded);
1344
1345 END:
1346         if (subnet)
1347                 loc_network_unref(subnet);
1348
1349         loc_network_list_unref(subnets);
1350
1351         return r;
1352 }
1353
1354 LOC_EXPORT int loc_database_enumerator_next_network(
1355                 struct loc_database_enumerator* enumerator, struct loc_network** network) {
1356         // Do not do anything if not in network mode
1357         if (enumerator->mode != LOC_DB_ENUMERATE_NETWORKS)
1358                 return 0;
1359
1360         // Flatten output?
1361         if (enumerator->flatten)
1362                 return __loc_database_enumerator_next_network_flattened(enumerator, network);
1363
1364         return __loc_database_enumerator_next_network(enumerator, network, 1);
1365 }
1366
1367 LOC_EXPORT int loc_database_enumerator_next_country(
1368                 struct loc_database_enumerator* enumerator, struct loc_country** country) {
1369         *country = NULL;
1370
1371         // Do not do anything if not in country mode
1372         if (enumerator->mode != LOC_DB_ENUMERATE_COUNTRIES)
1373                 return 0;
1374
1375         struct loc_database* db = enumerator->db;
1376
1377         while (enumerator->country_index < db->countries_count) {
1378                 // Fetch the next country
1379                 int r = loc_database_fetch_country(db, country, enumerator->country_index++);
1380                 if (r)
1381                         return r;
1382
1383                 // We do not filter here, so it always is a match
1384                 return 0;
1385         }
1386
1387         // Reset the index
1388         enumerator->country_index = 0;
1389
1390         // We have searched through all of them
1391         return 0;
1392 }