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: %zu\n", length);
 254                 return -EINVAL;
 255         }
 256
 257         DEBUG(db->ctx, "Reading signature of %zu 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         INFO(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 #ifdef ENABLE_DEBUG
 683         // Save start time
 684         clock_t start = clock();
 685 #endif
 686
 687         while (lo <= hi) {
 688                 off_t i = (lo + hi) / 2;
 689
 690                 // Fetch AS in the middle between lo and hi
 691                 int r = loc_database_fetch_as(db, as, i);
 692                 if (r)
 693                         return r;
 694
 695                 // Check if this is a match
 696                 uint32_t as_number = loc_as_get_number(*as);
 697                 if (as_number == number) {
 698 #ifdef ENABLE_DEBUG
 699                         clock_t end = clock();
 700
 701                         // Log how fast this has been
 702                         DEBUG(db->ctx, "Found AS%u in %.4fms\n", as_number,
 703                                 (double)(end - start) / CLOCKS_PER_SEC * 1000);
 704 #endif
 705
 706                         return 0;
 707                 }
 708
 709                 // If it wasn't, we release the AS and
 710                 // adjust our search pointers
 711                 loc_as_unref(*as);
 712
 713                 if (as_number < number) {
 714                         lo = i + 1;
 715                 } else
 716                         hi = i - 1;
 717         }
 718
 719         // Nothing found
 720         *as = NULL;
 721
 722         return 1;
 723 }
 724
 725 // Returns the network at position pos
 726 static int loc_database_fetch_network(struct loc_database* db, struct loc_network** network,
 727                 struct in6_addr* address, unsigned int prefix, off_t pos) {
 728         if ((size_t)pos >= db->networks_count) {
 729                 DEBUG(db->ctx, "Network ID out of range: %jd/%jd\n",
 730                         (intmax_t)pos, (intmax_t)db->networks_count);
 731                 return -EINVAL;
 732         }
 733
 734
 735         DEBUG(db->ctx, "Fetching network at position %jd\n", (intmax_t)pos);
 736
 737         int r;
 738         switch (db->version) {
 739                 case LOC_DATABASE_VERSION_1:
 740                         r = loc_network_new_from_database_v1(db->ctx, network,
 741                                 address, prefix, db->networks_v1 + pos);
 742                         break;
 743
 744                 default:
 745                         return -1;
 746         }
 747
 748 #ifdef ENABLE_DEBUG
 749         if (r == 0) {
 750                 char* string = loc_network_str(*network);
 751                 DEBUG(db->ctx, "Got network %s\n", string);
 752                 free(string);
 753         }
 754 #endif
 755
 756         return r;
 757 }
 758
 759 static int __loc_database_node_is_leaf(const struct loc_database_network_node_v1* node) {
 760         return (node->network != htobe32(0xffffffff));
 761 }
 762
 763 static int __loc_database_lookup_handle_leaf(struct loc_database* db, const struct in6_addr* address,
 764                 struct loc_network** network, struct in6_addr* network_address, unsigned int prefix,
 765                 const struct loc_database_network_node_v1* node) {
 766         off_t network_index = be32toh(node->network);
 767
 768         DEBUG(db->ctx, "Handling leaf node at %jd (%jd)\n", (intmax_t)(node - db->network_nodes_v1), (intmax_t)network_index);
 769
 770         // Fetch the network
 771         int r = loc_database_fetch_network(db, network,
 772                 network_address, prefix, network_index);
 773         if (r) {
 774                 ERROR(db->ctx, "Could not fetch network %jd from database\n", (intmax_t)network_index);
 775                 return r;
 776         }
 777
 778         // Check if the given IP address is inside the network
 779         if (!loc_network_match_address(*network, address)) {
 780                 DEBUG(db->ctx, "Searched address is not part of the network\n");
 781
 782                 loc_network_unref(*network);
 783                 *network = NULL;
 784                 return 1;
 785         }
 786
 787         // A network was found and the IP address matches
 788         return 0;
 789 }
 790
 791 // Searches for an exact match along the path
 792 static int __loc_database_lookup(struct loc_database* db, const struct in6_addr* address,
 793                 struct loc_network** network, struct in6_addr* network_address,
 794                 const struct loc_database_network_node_v1* node, unsigned int level) {
 795         int r;
 796         off_t node_index;
 797
 798         // Follow the path
 799         int bit = in6_addr_get_bit(address, level);
 800         in6_addr_set_bit(network_address, level, bit);
 801
 802         if (bit == 0)
 803                 node_index = be32toh(node->zero);
 804         else
 805                 node_index = be32toh(node->one);
 806
 807         // If the node index is zero, the tree ends here
 808         // and we cannot descend any further
 809         if (node_index > 0) {
 810                 // Check boundaries
 811                 if ((size_t)node_index >= db->network_nodes_count)
 812                         return -EINVAL;
 813
 814                 // Move on to the next node
 815                 r = __loc_database_lookup(db, address, network, network_address,
 816                         db->network_nodes_v1 + node_index, level + 1);
 817
 818                 // End here if a result was found
 819                 if (r == 0)
 820                         return r;
 821
 822                 // Raise any errors
 823                 else if (r < 0)
 824                         return r;
 825
 826                 DEBUG(db->ctx, "No match found below level %u\n", level);
 827         } else {
 828                 DEBUG(db->ctx, "Tree ended at level %u\n", level);
 829         }
 830
 831         // If this node has a leaf, we will check if it matches
 832         if (__loc_database_node_is_leaf(node)) {
 833                 r = __loc_database_lookup_handle_leaf(db, address, network, network_address, level, node);
 834                 if (r <= 0)
 835                         return r;
 836         }
 837
 838         return 1;
 839 }
 840
 841 LOC_EXPORT int loc_database_lookup(struct loc_database* db,
 842                 struct in6_addr* address, struct loc_network** network) {
 843         struct in6_addr network_address;
 844         memset(&network_address, 0, sizeof(network_address));
 845
 846         *network = NULL;
 847
 848 #ifdef ENABLE_DEBUG
 849         // Save start time
 850         clock_t start = clock();
 851 #endif
 852
 853         int r = __loc_database_lookup(db, address, network, &network_address,
 854                 db->network_nodes_v1, 0);
 855
 856 #ifdef ENABLE_DEBUG
 857         clock_t end = clock();
 858
 859         // Log how fast this has been
 860         DEBUG(db->ctx, "Executed network search in %.4fms\n",
 861                 (double)(end - start) / CLOCKS_PER_SEC * 1000);
 862 #endif
 863
 864         return r;
 865 }
 866
 867 LOC_EXPORT int loc_database_lookup_from_string(struct loc_database* db,
 868                 const char* string, struct loc_network** network) {
 869         struct in6_addr address;
 870
 871         int r = loc_parse_address(db->ctx, string, &address);
 872         if (r)
 873                 return r;
 874
 875         return loc_database_lookup(db, &address, network);
 876 }
 877
 878 // Returns the country at position pos
 879 static int loc_database_fetch_country(struct loc_database* db,
 880                 struct loc_country** country, off_t pos) {
 881         if ((size_t)pos >= db->countries_count)
 882                 return -EINVAL;
 883
 884         DEBUG(db->ctx, "Fetching country at position %jd\n", (intmax_t)pos);
 885
 886         int r;
 887         switch (db->version) {
 888                 case LOC_DATABASE_VERSION_1:
 889                         r = loc_country_new_from_database_v1(db->ctx, db->pool, country, db->countries_v1 + pos);
 890                         break;
 891
 892                 default:
 893                         return -1;
 894         }
 895
 896         if (r == 0) {
 897                 DEBUG(db->ctx, "Got country %s\n", loc_country_get_code(*country));
 898         }
 899
 900         return r;
 901 }
 902
 903 // Performs a binary search to find the country in the list
 904 LOC_EXPORT int loc_database_get_country(struct loc_database* db,
 905                 struct loc_country** country, const char* code) {
 906         off_t lo = 0;
 907         off_t hi = db->countries_count - 1;
 908
 909 #ifdef ENABLE_DEBUG
 910         // Save start time
 911         clock_t start = clock();
 912 #endif
 913
 914         while (lo <= hi) {
 915                 off_t i = (lo + hi) / 2;
 916
 917                 // Fetch country in the middle between lo and hi
 918                 int r = loc_database_fetch_country(db, country, i);
 919                 if (r)
 920                         return r;
 921
 922                 // Check if this is a match
 923                 const char* cc = loc_country_get_code(*country);
 924                 int result = strcmp(code, cc);
 925
 926                 if (result == 0) {
 927 #ifdef ENABLE_DEBUG
 928                         clock_t end = clock();
 929
 930                         // Log how fast this has been
 931                         DEBUG(db->ctx, "Found country %s in %.4fms\n", cc,
 932                                 (double)(end - start) / CLOCKS_PER_SEC * 1000);
 933 #endif
 934
 935                         return 0;
 936                 }
 937
 938                 // If it wasn't, we release the country and
 939                 // adjust our search pointers
 940                 loc_country_unref(*country);
 941
 942                 if (result > 0) {
 943                         lo = i + 1;
 944                 } else
 945                         hi = i - 1;
 946         }
 947
 948         // Nothing found
 949         *country = NULL;
 950
 951         return 1;
 952 }
 953
 954 // Enumerator
 955
 956 static void loc_database_enumerator_free(struct loc_database_enumerator* enumerator) {
 957         DEBUG(enumerator->ctx, "Releasing database enumerator %p\n", enumerator);
 958
 959         // Release all references
 960         loc_database_unref(enumerator->db);
 961         loc_unref(enumerator->ctx);
 962
 963         if (enumerator->string)
 964                 free(enumerator->string);
 965
 966         if (enumerator->countries)
 967                 loc_country_list_unref(enumerator->countries);
 968
 969         if (enumerator->asns)
 970                 loc_as_list_unref(enumerator->asns);
 971
 972         // Free network search
 973         free(enumerator->networks_visited);
 974
 975         // Free subnet stack
 976         if (enumerator->stack)
 977                 loc_network_list_unref(enumerator->stack);
 978
 979         free(enumerator);
 980 }
 981
 982 LOC_EXPORT int loc_database_enumerator_new(struct loc_database_enumerator** enumerator,
 983                 struct loc_database* db, enum loc_database_enumerator_mode mode, int flags) {
 984         struct loc_database_enumerator* e = calloc(1, sizeof(*e));
 985         if (!e)
 986                 return -ENOMEM;
 987
 988         // Reference context
 989         e->ctx = loc_ref(db->ctx);
 990         e->db = loc_database_ref(db);
 991         e->mode = mode;
 992         e->refcount = 1;
 993
 994         // Flatten output?
 995         e->flatten = (flags & LOC_DB_ENUMERATOR_FLAGS_FLATTEN);
 996
 997         // Initialise graph search
 998         e->network_stack_depth = 1;
 999         e->networks_visited = calloc(db->network_nodes_count, sizeof(*e->networks_visited));
1000
1001         // Allocate stack
1002         int r = loc_network_list_new(e->ctx, &e->stack);
1003         if (r) {
1004                 loc_database_enumerator_free(e);
1005                 return r;
1006         }
1007
1008         DEBUG(e->ctx, "Database enumerator object allocated at %p\n", e);
1009
1010         *enumerator = e;
1011         return 0;
1012 }
1013
1014 LOC_EXPORT struct loc_database_enumerator* loc_database_enumerator_ref(struct loc_database_enumerator* enumerator) {
1015         enumerator->refcount++;
1016
1017         return enumerator;
1018 }
1019
1020 LOC_EXPORT struct loc_database_enumerator* loc_database_enumerator_unref(struct loc_database_enumerator* enumerator) {
1021         if (!enumerator)
1022                 return NULL;
1023
1024         if (--enumerator->refcount > 0)
1025                 return enumerator;
1026
1027         loc_database_enumerator_free(enumerator);
1028         return NULL;
1029 }
1030
1031 LOC_EXPORT int loc_database_enumerator_set_string(struct loc_database_enumerator* enumerator, const char* string) {
1032         enumerator->string = strdup(string);
1033
1034         // Make the string lowercase
1035         for (char *p = enumerator->string; *p; p++)
1036                 *p = tolower(*p);
1037
1038         return 0;
1039 }
1040
1041 LOC_EXPORT struct loc_country_list* loc_database_enumerator_get_countries(
1042                 struct loc_database_enumerator* enumerator) {
1043         if (!enumerator->countries)
1044                 return NULL;
1045
1046         return loc_country_list_ref(enumerator->countries);
1047 }
1048
1049 LOC_EXPORT int loc_database_enumerator_set_countries(
1050                 struct loc_database_enumerator* enumerator, struct loc_country_list* countries) {
1051         if (enumerator->countries)
1052                 loc_country_list_unref(enumerator->countries);
1053
1054         enumerator->countries = loc_country_list_ref(countries);
1055
1056         return 0;
1057 }
1058
1059 LOC_EXPORT struct loc_as_list* loc_database_enumerator_get_asns(
1060                 struct loc_database_enumerator* enumerator) {
1061         if (!enumerator->asns)
1062                 return NULL;
1063
1064         return loc_as_list_ref(enumerator->asns);
1065 }
1066
1067 LOC_EXPORT int loc_database_enumerator_set_asns(
1068                 struct loc_database_enumerator* enumerator, struct loc_as_list* asns) {
1069         if (enumerator->asns)
1070                 loc_as_list_unref(enumerator->asns);
1071
1072         enumerator->asns = loc_as_list_ref(asns);
1073
1074         return 0;
1075 }
1076
1077 LOC_EXPORT int loc_database_enumerator_set_flag(
1078                 struct loc_database_enumerator* enumerator, enum loc_network_flags flag) {
1079         enumerator->flags |= flag;
1080
1081         return 0;
1082 }
1083
1084 LOC_EXPORT int loc_database_enumerator_set_family(
1085                 struct loc_database_enumerator* enumerator, int family) {
1086         enumerator->family = family;
1087
1088         return 0;
1089 }
1090
1091 LOC_EXPORT int loc_database_enumerator_next_as(
1092                 struct loc_database_enumerator* enumerator, struct loc_as** as) {
1093         *as = NULL;
1094
1095         // Do not do anything if not in AS mode
1096         if (enumerator->mode != LOC_DB_ENUMERATE_ASES)
1097                 return 0;
1098
1099         struct loc_database* db = enumerator->db;
1100
1101         while (enumerator->as_index < db->as_count) {
1102                 // Fetch the next AS
1103                 int r = loc_database_fetch_as(db, as, enumerator->as_index++);
1104                 if (r)
1105                         return r;
1106
1107                 r = loc_as_match_string(*as, enumerator->string);
1108                 if (r == 1) {
1109                         DEBUG(enumerator->ctx, "AS%d (%s) matches %s\n",
1110                                 loc_as_get_number(*as), loc_as_get_name(*as), enumerator->string);
1111
1112                         return 0;
1113                 }
1114
1115                 // No match
1116                 loc_as_unref(*as);
1117                 *as = NULL;
1118         }
1119
1120         // Reset the index
1121         enumerator->as_index = 0;
1122
1123         // We have searched through all of them
1124         return 0;
1125 }
1126
1127 static int loc_database_enumerator_stack_push_node(
1128                 struct loc_database_enumerator* e, off_t offset, int i, int depth) {
1129         // Do not add empty nodes
1130         if (!offset)
1131                 return 0;
1132
1133         // Check if there is any space left on the stack
1134         if (e->network_stack_depth >= MAX_STACK_DEPTH) {
1135                 ERROR(e->ctx, "Maximum stack size reached: %d\n", e->network_stack_depth);
1136                 return -1;
1137         }
1138
1139         // Increase stack size
1140         int s = ++e->network_stack_depth;
1141
1142         DEBUG(e->ctx, "Added node %jd to stack (%d)\n", (intmax_t)offset, depth);
1143
1144         e->network_stack[s].offset = offset;
1145         e->network_stack[s].i = i;
1146         e->network_stack[s].depth = depth;
1147
1148         return 0;
1149 }
1150
1151 static int loc_database_enumerator_filter_network(
1152                 struct loc_database_enumerator* enumerator, struct loc_network* network) {
1153         // Skip if the family does not match
1154         if (enumerator->family && loc_network_address_family(network) != enumerator->family) {
1155                 DEBUG(enumerator->ctx, "Filtered network %p because of family not matching\n", network);
1156                 return 1;
1157         }
1158
1159         // Skip if the country code does not match
1160         if (enumerator->countries && !loc_country_list_empty(enumerator->countries)) {
1161                 const char* country_code = loc_network_get_country_code(network);
1162
1163                 if (!loc_country_list_contains_code(enumerator->countries, country_code)) {
1164                         DEBUG(enumerator->ctx, "Filtered network %p because of country code not matching\n", network);
1165                         return 1;
1166                 }
1167         }
1168
1169         // Skip if the ASN does not match
1170         if (enumerator->asns && !loc_as_list_empty(enumerator->asns)) {
1171                 uint32_t asn = loc_network_get_asn(network);
1172
1173                 if (!loc_as_list_contains_number(enumerator->asns, asn)) {
1174                         DEBUG(enumerator->ctx, "Filtered network %p because of ASN not matching\n", network);
1175                         return 1;
1176                 }
1177         }
1178
1179         // Skip if flags do not match
1180         if (enumerator->flags && !loc_network_match_flag(network, enumerator->flags)) {
1181                 DEBUG(enumerator->ctx, "Filtered network %p because of flags not matching\n", network);
1182                 return 1;
1183         }
1184
1185         // Do not filter
1186         return 0;
1187 }
1188
1189 static int __loc_database_enumerator_next_network(
1190                 struct loc_database_enumerator* enumerator, struct loc_network** network, int filter) {
1191         // Return top element from the stack
1192         while (1) {
1193                 *network = loc_network_list_pop_first(enumerator->stack);
1194
1195                 // Stack is empty
1196                 if (!*network)
1197                         break;
1198
1199                 // Throw away any networks by filter
1200                 if (filter && loc_database_enumerator_filter_network(enumerator, *network)) {
1201                         loc_network_unref(*network);
1202                         *network = NULL;
1203                         continue;
1204                 }
1205
1206                 // Return result
1207                 return 0;
1208         }
1209
1210         DEBUG(enumerator->ctx, "Called with a stack of %u nodes\n",
1211                 enumerator->network_stack_depth);
1212
1213         // Perform DFS
1214         while (enumerator->network_stack_depth > 0) {
1215                 DEBUG(enumerator->ctx, "Stack depth: %u\n", enumerator->network_stack_depth);
1216
1217                 // Get object from top of the stack
1218                 struct loc_node_stack* node = &enumerator->network_stack[enumerator->network_stack_depth];
1219
1220                 // Remove the node from the stack if we have already visited it
1221                 if (enumerator->networks_visited[node->offset]) {
1222                         enumerator->network_stack_depth--;
1223                         continue;
1224                 }
1225
1226                 // Mark the bits on the path correctly
1227                 in6_addr_set_bit(&enumerator->network_address,
1228                         (node->depth > 0) ? node->depth - 1 : 0, node->i);
1229
1230                 DEBUG(enumerator->ctx, "Looking at node %jd\n", (intmax_t)node->offset);
1231                 enumerator->networks_visited[node->offset]++;
1232
1233                 // Pop node from top of the stack
1234                 struct loc_database_network_node_v1* n =
1235                         enumerator->db->network_nodes_v1 + node->offset;
1236
1237                 // Add edges to stack
1238                 int r = loc_database_enumerator_stack_push_node(enumerator,
1239                         be32toh(n->one), 1, node->depth + 1);
1240
1241                 if (r)
1242                         return r;
1243
1244                 r = loc_database_enumerator_stack_push_node(enumerator,
1245                         be32toh(n->zero), 0, node->depth + 1);
1246
1247                 if (r)
1248                         return r;
1249
1250                 // Check if this node is a leaf and has a network object
1251                 if (__loc_database_node_is_leaf(n)) {
1252                         off_t network_index = be32toh(n->network);
1253
1254                         DEBUG(enumerator->ctx, "Node has a network at %jd\n", (intmax_t)network_index);
1255
1256                         // Fetch the network object
1257                         r = loc_database_fetch_network(enumerator->db, network,
1258                                 &enumerator->network_address, node->depth, network_index);
1259
1260                         // Break on any errors
1261                         if (r)
1262                                 return r;
1263
1264                         // Return all networks when the filter is disabled
1265                         if (!filter)
1266                                 return 0;
1267
1268                         // Check if we are interested in this network
1269                         if (loc_database_enumerator_filter_network(enumerator, *network)) {
1270                                 loc_network_unref(*network);
1271                                 *network = NULL;
1272
1273                                 continue;
1274                         }
1275
1276                         return 0;
1277                 }
1278         }
1279
1280         // Reached the end of the search
1281         return 0;
1282 }
1283
1284 static int __loc_database_enumerator_next_network_flattened(
1285                 struct loc_database_enumerator* enumerator, struct loc_network** network) {
1286         // Fetch the next network
1287         int r = __loc_database_enumerator_next_network(enumerator, network, 1);
1288         if (r)
1289                 return r;
1290
1291         // End if we could not read another network
1292         if (!*network)
1293                 return 0;
1294
1295         struct loc_network* subnet = NULL;
1296         struct loc_network_list* subnets;
1297
1298         // Create a list with all subnets
1299         r = loc_network_list_new(enumerator->ctx, &subnets);
1300         if (r)
1301                 return r;
1302
1303         // Search all subnets from the database
1304         while (1) {
1305                 // Fetch the next network in line
1306                 r = __loc_database_enumerator_next_network(enumerator, &subnet, 0);
1307                 if (r) {
1308                         loc_network_unref(subnet);
1309                         loc_network_list_unref(subnets);
1310
1311                         return r;
1312                 }
1313
1314                 // End if we did not receive another subnet
1315                 if (!subnet)
1316                         break;
1317
1318                 // Collect all subnets in a list
1319                 if (loc_network_is_subnet(*network, subnet)) {
1320                         r = loc_network_list_push(subnets, subnet);
1321                         if (r) {
1322                                 loc_network_unref(subnet);
1323                                 loc_network_list_unref(subnets);
1324
1325                                 return r;
1326                         }
1327
1328                         loc_network_unref(subnet);
1329                         continue;
1330                 }
1331
1332                 // If this is not a subnet, we push it back onto the stack and break
1333                 r = loc_network_list_push(enumerator->stack, subnet);
1334                 if (r) {
1335                         loc_network_unref(subnet);
1336                         loc_network_list_unref(subnets);
1337
1338                         return r;
1339                 }
1340
1341                 loc_network_unref(subnet);
1342                 break;
1343         }
1344
1345         DEBUG(enumerator->ctx, "Found %zu subnet(s)\n", loc_network_list_size(subnets));
1346
1347         // We can abort here if the network has no subnets
1348         if (loc_network_list_empty(subnets)) {
1349                 loc_network_list_unref(subnets);
1350
1351                 return 0;
1352         }
1353
1354         // If the network has any subnets, we will break it into smaller parts
1355         // without the subnets.
1356         struct loc_network_list* excluded = loc_network_exclude_list(*network, subnets);
1357         if (!excluded) {
1358                 loc_network_list_unref(subnets);
1359                 return -1;
1360         }
1361
1362         // Merge subnets onto the stack
1363         r = loc_network_list_merge(enumerator->stack, subnets);
1364         if (r) {
1365                 loc_network_list_unref(subnets);
1366                 loc_network_list_unref(excluded);
1367
1368                 return r;
1369         }
1370
1371         // Push excluded list onto the stack
1372         r = loc_network_list_merge(enumerator->stack, excluded);
1373         if (r) {
1374                 loc_network_list_unref(subnets);
1375                 loc_network_list_unref(excluded);
1376
1377                 return r;
1378         }
1379
1380         loc_network_list_unref(subnets);
1381         loc_network_list_unref(excluded);
1382
1383         // Drop the network and restart the whole process again to pick the next network
1384         loc_network_unref(*network);
1385
1386         return __loc_database_enumerator_next_network_flattened(enumerator, network);
1387 }
1388
1389 LOC_EXPORT int loc_database_enumerator_next_network(
1390                 struct loc_database_enumerator* enumerator, struct loc_network** network) {
1391         // Do not do anything if not in network mode
1392         if (enumerator->mode != LOC_DB_ENUMERATE_NETWORKS)
1393                 return 0;
1394
1395         // Flatten output?
1396         if (enumerator->flatten)
1397                 return __loc_database_enumerator_next_network_flattened(enumerator, network);
1398
1399         return __loc_database_enumerator_next_network(enumerator, network, 1);
1400 }
1401
1402 LOC_EXPORT int loc_database_enumerator_next_country(
1403                 struct loc_database_enumerator* enumerator, struct loc_country** country) {
1404         *country = NULL;
1405
1406         // Do not do anything if not in country mode
1407         if (enumerator->mode != LOC_DB_ENUMERATE_COUNTRIES)
1408                 return 0;
1409
1410         struct loc_database* db = enumerator->db;
1411
1412         while (enumerator->country_index < db->countries_count) {
1413                 // Fetch the next country
1414                 int r = loc_database_fetch_country(db, country, enumerator->country_index++);
1415                 if (r)
1416                         return r;
1417
1418                 // We do not filter here, so it always is a match
1419                 return 0;
1420         }
1421
1422         // Reset the index
1423         enumerator->country_index = 0;
1424
1425         // We have searched through all of them
1426         return 0;
1427 }