keydb_fs.c

   1 /*
   2  * keydb.h - Routines to store and fetch keys.
   3  *
   4  * Daniel Silverstone <dsilvers@digital-scurf.org>
   5  *
   6  * Copyright 2004 Daniel Silverstone and Project Purple
   7  */
   8
   9 #include <sys/types.h>
  10 #include <sys/uio.h>
  11 #include <sys/stat.h>
  12 #include <errno.h>
  13 #include <fcntl.h>
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <string.h>
  17 #include <unistd.h>
  18 #include <limits.h>
  19 #include <dirent.h>
  20
  21 #include "charfuncs.h"
  22 #include "decodekey.h"
  23 #include "keydb.h"
  24 #include "keyid.h"
  25 #include "keystructs.h"
  26 #include "ll.h"
  27 #include "mem.h"
  28 #include "onak-conf.h"
  29 #include "parsekey.h"
  30 #include "log.h"
  31 #include "wordlist.h"
  32
  33 /* Hack: We should really dynamically allocate our path buffers */
  34 #ifndef PATH_MAX
  35 #define PATH_MAX 1024
  36 #endif
  37
  38 static int keydb_lockfile_fd = -1;
  39 static bool keydb_lockfile_readonly;
  40
  41 /*****************************************************************************/
  42
  43 /* Helper functions */
  44
  45 #define FNV_offset_basis 2166136261ul
  46 #define FNV_mixing_prime 16777619ul
  47
  48 static uint32_t calchash(uint8_t * ptr)
  49 {
  50         register uint32_t h = FNV_offset_basis;
  51         register uint32_t p = FNV_mixing_prime;
  52         register uint32_t n = strlen((char *) ptr);
  53         register uint8_t *c = ptr;
  54         while (n--) {
  55                 h *= p;
  56                 h ^= *c++;
  57         }
  58         return h ? h : 1;       /* prevent a hash of zero happening */
  59 }
  60
  61
  62 static void keypath(char *buffer, size_t length, uint64_t _keyid)
  63 {
  64         uint64_t keyid = _keyid << 32;
  65         snprintf(buffer, length, "%s/key/%02X/%02X/%08X/%016" PRIX64,
  66                  config.db_dir, (uint8_t) ((keyid >> 56) & 0xFF),
  67                  (uint8_t) ((keyid >> 48) & 0xFF),
  68                  (uint32_t) (keyid >> 32), _keyid);
  69 }
  70
  71 static void keydir(char *buffer, size_t length, uint64_t _keyid)
  72 {
  73         uint64_t keyid = _keyid << 32;
  74         snprintf(buffer, length, "%s/key/%02X/%02X/%08X", config.db_dir,
  75                  (uint8_t) ((keyid >> 56) & 0xFF),
  76                  (uint8_t) ((keyid >> 48) & 0xFF),
  77                  (uint32_t) (keyid >> 32));
  78 }
  79
  80 static void prove_path_to(uint64_t keyid, char *what)
  81 {
  82         static char buffer[PATH_MAX];
  83         snprintf(buffer, sizeof(buffer), "%s/%s", config.db_dir, what);
  84         mkdir(buffer, 0777);
  85
  86         snprintf(buffer, sizeof(buffer), "%s/%s/%02X", config.db_dir, what,
  87                  (uint8_t) ((keyid >> 24) & 0xFF));
  88         mkdir(buffer, 0777);
  89
  90         snprintf(buffer, sizeof(buffer), "%s/%s/%02X/%02X", config.db_dir,
  91                  what,
  92                  (uint8_t) ((keyid >> 24) & 0xFF),
  93                  (uint8_t) ((keyid >> 16) & 0xFF));
  94         mkdir(buffer, 0777);
  95
  96         snprintf(buffer, sizeof(buffer), "%s/%s/%02X/%02X/%08X", config.db_dir,
  97                  what,
  98                  (uint8_t) ((keyid >> 24) & 0xFF),
  99                  (uint8_t) ((keyid >> 16) & 0xFF), (uint32_t) (keyid));
 100         mkdir(buffer, 0777);
 101 }
 102
 103 static void wordpath(char *buffer, size_t length, char *word, uint32_t hash,
 104                 uint64_t keyid)
 105 {
 106         snprintf(buffer, length, "%s/words/%02X/%02X/%08X/%s/%016" PRIX64,
 107                  config.db_dir, (uint8_t) ((hash >> 24) & 0xFF),
 108                  (uint8_t) ((hash >> 16) & 0xFF), hash, word, keyid);
 109 }
 110
 111 static void worddir(char *buffer, size_t length, char *word, uint32_t hash)
 112 {
 113         snprintf(buffer, length, "%s/words/%02X/%02X/%08X/%s", config.db_dir,
 114                  (uint8_t) ((hash >> 24) & 0xFF),
 115                  (uint8_t) ((hash >> 16) & 0xFF), hash, word);
 116 }
 117
 118 static void subkeypath(char *buffer, size_t length, uint64_t subkey,
 119                 uint64_t keyid)
 120 {
 121         snprintf(buffer, length, "%s/subkeys/%02X/%02X/%08X/%016" PRIX64,
 122                  config.db_dir,
 123                  (uint8_t) ((subkey >> 24) & 0xFF),
 124                  (uint8_t) ((subkey >> 16) & 0xFF),
 125                  (uint32_t) (subkey & 0xFFFFFFFF),
 126                  keyid);
 127 }
 128
 129 static void skshashpath(char *buffer, size_t length,
 130                 const struct skshash *hash)
 131 {
 132         snprintf(buffer, length, "%s/skshash/%02X/%02X/%02X%02X%02X%02X/"
 133                 "%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X",
 134                  config.db_dir,
 135                  hash->hash[0], hash->hash[1],
 136                  hash->hash[0], hash->hash[1], hash->hash[2], hash->hash[3],
 137                  hash->hash[4], hash->hash[5], hash->hash[6], hash->hash[7],
 138                  hash->hash[8], hash->hash[9], hash->hash[10], hash->hash[11],
 139                  hash->hash[12], hash->hash[13], hash->hash[14],
 140                  hash->hash[15]);
 141 }
 142 static void subkeydir(char *buffer, size_t length, uint64_t subkey)
 143 {
 144         snprintf(buffer, length, "%s/subkeys/%02X/%02X/%08X",
 145                  config.db_dir,
 146                  (uint8_t) ((subkey >> 24) & 0xFF),
 147                  (uint8_t) ((subkey >> 16) & 0xFF),
 148                  (uint32_t) (subkey & 0xFFFFFFFF));
 149 }
 150
 151 /*****************************************************************************/
 152
 153 /**
 154  *      initdb - Initialize the key database.
 155  */
 156 static void fs_initdb(bool readonly)
 157 {
 158         char buffer[PATH_MAX];
 159
 160         keydb_lockfile_readonly = readonly;
 161
 162         snprintf(buffer, sizeof(buffer), "%s/.lock", config.db_dir);
 163
 164         if (access(config.db_dir, R_OK | W_OK | X_OK) == -1) {
 165                 if (errno != ENOENT) {
 166                         logthing(LOGTHING_CRITICAL,
 167                                  "Unable to access keydb_fs root of '%s'. (%s)",
 168                                  config.db_dir, strerror(errno));
 169                         exit(1);        /* Lacking rwx on the key dir */
 170                 }
 171                 mkdir(config.db_dir, 0777);
 172                 keydb_lockfile_fd = open(buffer, O_RDWR | O_CREAT, 0600);
 173         }
 174         chdir(config.db_dir);
 175         if (keydb_lockfile_fd == -1)
 176                 keydb_lockfile_fd = open(buffer,
 177                                          (keydb_lockfile_readonly) ?
 178                                          O_RDONLY : O_RDWR);
 179         if (keydb_lockfile_fd == -1)
 180                 keydb_lockfile_fd = open(buffer, O_RDWR | O_CREAT, 0600);
 181         if (keydb_lockfile_fd == -1) {
 182                 logthing(LOGTHING_CRITICAL,
 183                          "Unable to open lockfile '%s'. (%s)",
 184                          buffer, strerror(errno));
 185                 exit(1);        /* Lacking rwx on the key dir */
 186         }
 187 }
 188
 189 /**
 190  *      cleanupdb - De-initialize the key database.
 191  */
 192 static void fs_cleanupdb(void)
 193 {
 194         /* Mmmm nothing to do here? */
 195         close(keydb_lockfile_fd);
 196 }
 197
 198 /**
 199  *      starttrans - Start a transaction.
 200  */
 201 static bool fs_starttrans(void)
 202 {
 203         struct flock lockstruct;
 204         int remaining = 20;
 205         lockstruct.l_type =
 206             F_RDLCK | ((keydb_lockfile_readonly) ? 0 : F_WRLCK);
 207         lockstruct.l_whence = SEEK_SET;
 208         lockstruct.l_start = 0;
 209         lockstruct.l_len = 1;
 210
 211         while (fcntl(keydb_lockfile_fd, F_SETLK, &lockstruct) == -1) {
 212                 if (remaining-- == 0)
 213                         return false;   /* Hope to hell that noodles DTRT */
 214                 usleep(100);
 215         }
 216         return true;
 217 }
 218
 219 /**
 220  *      endtrans - End a transaction.
 221  */
 222 static void fs_endtrans(void)
 223 {
 224         struct flock lockstruct;
 225
 226         lockstruct.l_type = F_UNLCK;
 227         lockstruct.l_whence = SEEK_SET;
 228         lockstruct.l_start = 0;
 229         lockstruct.l_len = 1;
 230         fcntl(keydb_lockfile_fd, F_SETLK, &lockstruct);
 231 }
 232
 233 static uint64_t fs_getfullkeyid(uint64_t keyid)
 234 {
 235         static char buffer[PATH_MAX];
 236         DIR *d = NULL;
 237         struct dirent *de = NULL;
 238         uint64_t ret = 0;
 239
 240         keydir(buffer, sizeof(buffer), keyid);
 241
 242         d = opendir(buffer);
 243         if (d) {
 244                 do {
 245                         de = readdir(d);
 246                         if (de && de->d_name[0] != '.') {
 247                                 ret = strtoull(de->d_name, NULL, 16);
 248                         }
 249                 } while (de && de->d_name[0] == '.');
 250                 closedir(d);
 251         }
 252
 253         if (ret == 0) {
 254                 subkeydir(buffer, sizeof(buffer), keyid);
 255
 256                 d = opendir(buffer);
 257                 if (d) {
 258                         do {
 259                                 de = readdir(d);
 260                                 if (de && de->d_name[0] != '.') {
 261                                         ret = strtoull(de->d_name, NULL, 16);
 262                                 }
 263                         } while (de && de->d_name[0] == '.');
 264                         closedir(d);
 265                 }
 266         }
 267
 268         return ret;
 269 }
 270
 271 /**
 272  *      fetch_key - Given a keyid fetch the key from storage.
 273  *      @keyid: The keyid to fetch.
 274  *      @publickey: A pointer to a structure to return the key in.
 275  *      @intrans: If we're already in a transaction.
 276  */
 277 static int fs_fetch_key(uint64_t keyid, struct openpgp_publickey **publickey,
 278               bool intrans)
 279 {
 280         static char buffer[PATH_MAX];
 281         int ret = 0, fd;
 282         struct openpgp_packet_list *packets = NULL;
 283
 284         if (!intrans)
 285                 fs_starttrans();
 286
 287         if ((keyid >> 32) == 0)
 288                 keyid = fs_getfullkeyid(keyid);
 289
 290         keypath(buffer, sizeof(buffer), keyid);
 291         if ((fd = open(buffer, O_RDONLY)) != -1) {
 292                 /* File is present, load it in... */
 293                 read_openpgp_stream(file_fetchchar, &fd, &packets, 0);
 294                 parse_keys(packets, publickey);
 295                 free_packet_list(packets);
 296                 packets = NULL;
 297                 close(fd);
 298                 ret = 1;
 299         }
 300
 301         if (!intrans)
 302                 fs_endtrans();
 303         return ret;
 304 }
 305
 306 /**
 307  *      store_key - Takes a key and stores it.
 308  *      @publickey: A pointer to the public key to store.
 309  *      @intrans: If we're already in a transaction.
 310  *      @update: If true the key exists and should be updated.
 311  */
 312 static int fs_store_key(struct openpgp_publickey *publickey, bool intrans,
 313               bool update)
 314 {
 315         static char buffer[PATH_MAX];
 316         static char wbuffer[PATH_MAX];
 317         int ret = 0, fd;
 318         struct openpgp_packet_list *packets = NULL;
 319         struct openpgp_packet_list *list_end = NULL;
 320         struct openpgp_publickey *next = NULL;
 321         uint64_t keyid = get_keyid(publickey);
 322         struct ll *wordlist = NULL, *wl = NULL;
 323         struct skshash hash;
 324         uint64_t *subkeyids = NULL;
 325         uint32_t hashid;
 326         int i = 0;
 327
 328
 329         if (!intrans)
 330                 fs_starttrans();
 331
 332         prove_path_to(keyid, "key");
 333         keypath(buffer, sizeof(buffer), keyid);
 334
 335         if ((fd =
 336              open(buffer, O_WRONLY | (update ? O_TRUNC : O_CREAT),
 337                   0644)) != -1) {
 338                 next = publickey->next;
 339                 publickey->next = NULL;
 340                 flatten_publickey(publickey, &packets, &list_end);
 341                 publickey->next = next;
 342
 343                 write_openpgp_stream(file_putchar, &fd, packets);
 344                 close(fd);
 345                 free_packet_list(packets);
 346                 packets = NULL;
 347                 ret = 1;
 348         }
 349
 350         if (ret) {
 351                 wl = wordlist = makewordlistfromkey(wordlist, publickey);
 352                 while (wl) {
 353                         uint32_t hash = calchash((uint8_t *) (wl->object));
 354                         prove_path_to(hash, "words");
 355
 356                         worddir(wbuffer, sizeof(wbuffer), wl->object, hash);
 357                         mkdir(wbuffer, 0777);
 358                         wordpath(wbuffer, sizeof(wbuffer), wl->object, hash,
 359                                 keyid);
 360                         link(buffer, wbuffer);
 361
 362                         wl = wl->next;
 363                 }
 364                 llfree(wordlist, free);
 365
 366                 subkeyids = keysubkeys(publickey);
 367                 i = 0;
 368                 while (subkeyids != NULL && subkeyids[i] != 0) {
 369                         prove_path_to(subkeyids[i], "subkeys");
 370
 371                         subkeydir(wbuffer, sizeof(wbuffer), subkeyids[i]);
 372                         mkdir(wbuffer, 0777);
 373                         subkeypath(wbuffer, sizeof(wbuffer), subkeyids[i],
 374                                 keyid);
 375                         link(buffer, wbuffer);
 376
 377                         i++;
 378                 }
 379                 if (subkeyids != NULL) {
 380                         free(subkeyids);
 381                         subkeyids = NULL;
 382                 }
 383
 384                 get_skshash(publickey, &hash);
 385                 hashid = (hash.hash[0] << 24) + (hash.hash[1] << 16) +
 386                                 (hash.hash[2] << 8) + hash.hash[3];
 387                 prove_path_to(hashid, "skshash");
 388                 skshashpath(wbuffer, sizeof(wbuffer), &hash);
 389                 link(buffer, wbuffer);
 390         }
 391
 392         if (!intrans)
 393                 fs_endtrans();
 394         return ret;
 395 }
 396
 397 /**
 398  *      delete_key - Given a keyid delete the key from storage.
 399  *      @keyid: The keyid to delete.
 400  *      @intrans: If we're already in a transaction.
 401  */
 402 static int fs_delete_key(uint64_t keyid, bool intrans)
 403 {
 404         static char buffer[PATH_MAX];
 405         int ret;
 406         struct openpgp_publickey *pk = NULL;
 407         struct skshash hash;
 408         struct ll *wordlist = NULL, *wl = NULL;
 409         uint64_t *subkeyids = NULL;
 410         int i = 0;
 411
 412         if ((keyid >> 32) == 0)
 413                 keyid = fs_getfullkeyid(keyid);
 414
 415         if (!intrans)
 416                 fs_starttrans();
 417
 418         ret = fs_fetch_key(keyid, &pk, true);
 419
 420         if (ret) {
 421                 logthing(LOGTHING_DEBUG, "Wordlist for key %016" PRIX64,
 422                          keyid);
 423                 wl = wordlist = makewordlistfromkey(wordlist, pk);
 424                 logthing(LOGTHING_DEBUG,
 425                          "Wordlist for key %016" PRIX64 " done", keyid);
 426                 while (wl) {
 427                         uint32_t hash = calchash((uint8_t *) (wl->object));
 428                         prove_path_to(hash, "words");
 429
 430                         wordpath(buffer, sizeof(buffer), wl->object, hash,
 431                                 keyid);
 432                         unlink(buffer);
 433
 434                         wl = wl->next;
 435                 }
 436
 437                 subkeyids = keysubkeys(pk);
 438                 i = 0;
 439                 while (subkeyids != NULL && subkeyids[i] != 0) {
 440                         prove_path_to(subkeyids[i], "subkeys");
 441
 442                         subkeypath(buffer, sizeof(buffer), subkeyids[i],
 443                                 keyid);
 444                         unlink(buffer);
 445
 446                         i++;
 447                 }
 448                 if (subkeyids != NULL) {
 449                         free(subkeyids);
 450                         subkeyids = NULL;
 451                 }
 452
 453                 get_skshash(pk, &hash);
 454                 skshashpath(buffer, sizeof(buffer), &hash);
 455                 unlink(buffer);
 456         }
 457
 458         keypath(buffer, sizeof(buffer), keyid);
 459         unlink(buffer);
 460
 461         if (!intrans)
 462                 fs_endtrans();
 463         return 1;
 464 }
 465
 466 static struct ll *internal_get_key_by_word(char *word, struct ll *mct)
 467 {
 468         struct ll *keys = NULL;
 469         DIR *d = NULL;
 470         char buffer[PATH_MAX];
 471         uint32_t hash = calchash((uint8_t *) (word));
 472         struct dirent *de;
 473
 474         worddir(buffer, sizeof(buffer), word, hash);
 475         d = opendir(buffer);
 476         logthing(LOGTHING_DEBUG, "Scanning for word %s in dir %s", word,
 477                  buffer);
 478         if (d)
 479                 do {
 480                         de = readdir(d);
 481                         if (de && de->d_name[0] != '.') {
 482                                 if ((!mct)
 483                                     || (llfind(mct, de->d_name,
 484                                         (int (*)(const void *, const void *))
 485                                                     strcmp) !=
 486                                         NULL)) {
 487                                         logthing(LOGTHING_DEBUG,
 488                                                  "Found %s // %s", word,
 489                                                  de->d_name);
 490                                         keys =
 491                                             lladd(keys,
 492                                                   strdup(de->d_name));
 493                                 }
 494                         }
 495                 } while (de);
 496         closedir(d);
 497
 498         return keys;
 499 }
 500
 501 /*
 502  *      fetch_key_text - Trys to find the keys that contain the supplied text.
 503  *      @search: The text to search for.
 504  *      @publickey: A pointer to a structure to return the key in.
 505  */
 506 static int fs_fetch_key_text(const char *search,
 507                    struct openpgp_publickey **publickey)
 508 {
 509         struct ll *wordlist = NULL, *wl = NULL;
 510         struct ll *keylist = NULL;
 511         char      *searchtext = NULL;
 512         int addedkeys = 0;
 513
 514         logthing(LOGTHING_DEBUG, "Search was '%s'", search);
 515
 516         searchtext = strdup(search);
 517         wl = wordlist = makewordlist(wordlist, searchtext);
 518
 519         keylist = internal_get_key_by_word(wordlist->object, NULL);
 520
 521         if (!keylist) {
 522                 llfree(wordlist, NULL);
 523                 free(searchtext);
 524                 searchtext = NULL;
 525                 return 0;
 526         }
 527
 528         wl = wl->next;
 529         while (wl) {
 530                 struct ll *nkl =
 531                     internal_get_key_by_word(wl->object, keylist);
 532                 if (!nkl) {
 533                         llfree(wordlist, NULL);
 534                         llfree(keylist, free);
 535                         free(searchtext);
 536                         searchtext = NULL;
 537                         return 0;
 538                 }
 539                 llfree(keylist, free);
 540                 keylist = nkl;
 541                 wl = wl->next;
 542         }
 543
 544         llfree(wordlist, NULL);
 545
 546         /* Now add the keys... */
 547         wl = keylist;
 548         while (wl) {
 549                 logthing(LOGTHING_DEBUG, "Adding key: %s", wl->object);
 550                 addedkeys +=
 551                     fs_fetch_key(strtoull(wl->object, NULL, 16), publickey,
 552                               false);
 553                 if (addedkeys >= config.maxkeys)
 554                         break;
 555                 wl = wl->next;
 556         }
 557
 558         llfree(keylist, free);
 559         free(searchtext);
 560         searchtext = NULL;
 561
 562         return addedkeys;
 563 }
 564
 565 /**
 566  *      fetch_key_skshash - Given an SKS hash fetch the key from storage.
 567  *      @hash: The hash to fetch.
 568  *      @publickey: A pointer to a structure to return the key in.
 569  *      @intrans: If we're already in a transaction.
 570  */
 571 static int fs_fetch_key_skshash(const struct skshash *hash,
 572               struct openpgp_publickey **publickey)
 573 {
 574         static char buffer[PATH_MAX];
 575         int ret = 0, fd;
 576         struct openpgp_packet_list *packets = NULL;
 577
 578         skshashpath(buffer, sizeof(buffer), hash);
 579         if ((fd = open(buffer, O_RDONLY)) != -1) {
 580                 read_openpgp_stream(file_fetchchar, &fd, &packets, 0);
 581                 parse_keys(packets, publickey);
 582                 free_packet_list(packets);
 583                 packets = NULL;
 584                 close(fd);
 585                 ret = 1;
 586         }
 587
 588         return ret;
 589 }
 590
 591 /**
 592  *      iterate_keys - call a function once for each key in the db.
 593  *      @iterfunc: The function to call.
 594  *      @ctx: A context pointer
 595  *
 596  *      Calls iterfunc once for each key in the database. ctx is passed
 597  *      unaltered to iterfunc. This function is intended to aid database dumps
 598  *      and statistic calculations.
 599  *
 600  *      Returns the number of keys we iterated over.
 601  */
 602 static int fs_iterate_keys(void (*iterfunc)(void *ctx,
 603                 struct openpgp_publickey *key), void *ctx)
 604 {
 605         return 0;
 606 }
 607
 608 /*
 609  * Include the basic keydb routines.
 610  */
 611 #define NEED_KEYID2UID 1
 612 #define NEED_GETKEYSIGS 1
 613 #define NEED_UPDATEKEYS 1
 614 #include "keydb.c"
 615
 616 struct dbfuncs keydb_fs_funcs = {
 617         .initdb                 = fs_initdb,
 618         .cleanupdb              = fs_cleanupdb,
 619         .starttrans             = fs_starttrans,
 620         .endtrans               = fs_endtrans,
 621         .fetch_key              = fs_fetch_key,
 622         .fetch_key_text         = fs_fetch_key_text,
 623         .fetch_key_skshash      = fs_fetch_key_skshash,
 624         .store_key              = fs_store_key,
 625         .update_keys            = generic_update_keys,
 626         .delete_key             = fs_delete_key,
 627         .getkeysigs             = generic_getkeysigs,
 628         .cached_getkeysigs      = generic_cached_getkeysigs,
 629         .keyid2uid              = generic_keyid2uid,
 630         .getfullkeyid           = fs_getfullkeyid,
 631         .iterate_keys           = fs_iterate_keys,
 632 };