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 subkeydir(char *buffer, size_t length, uint64_t subkey)
 130 {
 131         snprintf(buffer, length, "%s/subkeys/%02X/%02X/%08X",
 132                  config.db_dir,
 133                  (uint8_t) ((subkey >> 24) & 0xFF),
 134                  (uint8_t) ((subkey >> 16) & 0xFF),
 135                  (uint32_t) (subkey & 0xFFFFFFFF));
 136 }
 137
 138 /*****************************************************************************/
 139
 140 /**
 141  *      initdb - Initialize the key database.
 142  */
 143 static void fs_initdb(bool readonly)
 144 {
 145         char buffer[PATH_MAX];
 146
 147         keydb_lockfile_readonly = readonly;
 148
 149         snprintf(buffer, sizeof(buffer), "%s/.lock", config.db_dir);
 150
 151         if (access(config.db_dir, R_OK | W_OK | X_OK) == -1) {
 152                 if (errno != ENOENT) {
 153                         logthing(LOGTHING_CRITICAL,
 154                                  "Unable to access keydb_fs root of '%s'. (%s)",
 155                                  config.db_dir, strerror(errno));
 156                         exit(1);        /* Lacking rwx on the key dir */
 157                 }
 158                 mkdir(config.db_dir, 0777);
 159                 keydb_lockfile_fd = open(buffer, O_RDWR | O_CREAT, 0600);
 160         }
 161         chdir(config.db_dir);
 162         if (keydb_lockfile_fd == -1)
 163                 keydb_lockfile_fd = open(buffer,
 164                                          (keydb_lockfile_readonly) ?
 165                                          O_RDONLY : O_RDWR);
 166         if (keydb_lockfile_fd == -1)
 167                 keydb_lockfile_fd = open(buffer, O_RDWR | O_CREAT, 0600);
 168         if (keydb_lockfile_fd == -1) {
 169                 logthing(LOGTHING_CRITICAL,
 170                          "Unable to open lockfile '%s'. (%s)",
 171                          buffer, strerror(errno));
 172                 exit(1);        /* Lacking rwx on the key dir */
 173         }
 174 }
 175
 176 /**
 177  *      cleanupdb - De-initialize the key database.
 178  */
 179 static void fs_cleanupdb(void)
 180 {
 181         /* Mmmm nothing to do here? */
 182         close(keydb_lockfile_fd);
 183 }
 184
 185 /**
 186  *      starttrans - Start a transaction.
 187  */
 188 static bool fs_starttrans(void)
 189 {
 190         struct flock lockstruct;
 191         int remaining = 20;
 192         lockstruct.l_type =
 193             F_RDLCK | ((keydb_lockfile_readonly) ? 0 : F_WRLCK);
 194         lockstruct.l_whence = SEEK_SET;
 195         lockstruct.l_start = 0;
 196         lockstruct.l_len = 1;
 197
 198         while (fcntl(keydb_lockfile_fd, F_SETLK, &lockstruct) == -1) {
 199                 if (remaining-- == 0)
 200                         return false;   /* Hope to hell that noodles DTRT */
 201                 usleep(100);
 202         }
 203         return true;
 204 }
 205
 206 /**
 207  *      endtrans - End a transaction.
 208  */
 209 static void fs_endtrans(void)
 210 {
 211         struct flock lockstruct;
 212
 213         lockstruct.l_type = F_UNLCK;
 214         lockstruct.l_whence = SEEK_SET;
 215         lockstruct.l_start = 0;
 216         lockstruct.l_len = 1;
 217         fcntl(keydb_lockfile_fd, F_SETLK, &lockstruct);
 218 }
 219
 220 static uint64_t fs_getfullkeyid(uint64_t keyid)
 221 {
 222         static char buffer[PATH_MAX];
 223         DIR *d = NULL;
 224         struct dirent *de = NULL;
 225         uint64_t ret = 0;
 226
 227         keydir(buffer, sizeof(buffer), keyid);
 228
 229         d = opendir(buffer);
 230         if (d) {
 231                 do {
 232                         de = readdir(d);
 233                         if (de && de->d_name[0] != '.') {
 234                                 ret = strtoull(de->d_name, NULL, 16);
 235                         }
 236                 } while (de && de->d_name[0] == '.');
 237                 closedir(d);
 238         }
 239
 240         if (ret == 0) {
 241                 subkeydir(buffer, sizeof(buffer), keyid);
 242
 243                 d = opendir(buffer);
 244                 if (d) {
 245                         do {
 246                                 de = readdir(d);
 247                                 if (de && de->d_name[0] != '.') {
 248                                         ret = strtoull(de->d_name, NULL, 16);
 249                                 }
 250                         } while (de && de->d_name[0] == '.');
 251                         closedir(d);
 252                 }
 253         }
 254
 255         return ret;
 256 }
 257
 258 /**
 259  *      fetch_key - Given a keyid fetch the key from storage.
 260  *      @keyid: The keyid to fetch.
 261  *      @publickey: A pointer to a structure to return the key in.
 262  *      @intrans: If we're already in a transaction.
 263  */
 264 static int fs_fetch_key(uint64_t keyid, struct openpgp_publickey **publickey,
 265               bool intrans)
 266 {
 267         static char buffer[PATH_MAX];
 268         int ret = 0, fd;
 269         struct openpgp_packet_list *packets = NULL;
 270
 271         if (!intrans)
 272                 fs_starttrans();
 273
 274         if ((keyid >> 32) == 0)
 275                 keyid = fs_getfullkeyid(keyid);
 276
 277         keypath(buffer, sizeof(buffer), keyid);
 278         if ((fd = open(buffer, O_RDONLY)) != -1) {
 279                 /* File is present, load it in... */
 280                 read_openpgp_stream(file_fetchchar, &fd, &packets, 0);
 281                 parse_keys(packets, publickey);
 282                 free_packet_list(packets);
 283                 packets = NULL;
 284                 close(fd);
 285                 ret = 1;
 286         }
 287
 288         if (!intrans)
 289                 fs_endtrans();
 290         return ret;
 291 }
 292
 293 /**
 294  *      store_key - Takes a key and stores it.
 295  *      @publickey: A pointer to the public key to store.
 296  *      @intrans: If we're already in a transaction.
 297  *      @update: If true the key exists and should be updated.
 298  */
 299 static int fs_store_key(struct openpgp_publickey *publickey, bool intrans,
 300               bool update)
 301 {
 302         static char buffer[PATH_MAX];
 303         static char wbuffer[PATH_MAX];
 304         int ret = 0, fd;
 305         struct openpgp_packet_list *packets = NULL;
 306         struct openpgp_packet_list *list_end = NULL;
 307         struct openpgp_publickey *next = NULL;
 308         uint64_t keyid = get_keyid(publickey);
 309         struct ll *wordlist = NULL, *wl = NULL;
 310         uint64_t *subkeyids = NULL;
 311         int i = 0;
 312
 313
 314         if (!intrans)
 315                 fs_starttrans();
 316
 317         prove_path_to(keyid, "key");
 318         keypath(buffer, sizeof(buffer), keyid);
 319
 320         if ((fd =
 321              open(buffer, O_WRONLY | (update ? O_TRUNC : O_CREAT),
 322                   0644)) != -1) {
 323                 next = publickey->next;
 324                 publickey->next = NULL;
 325                 flatten_publickey(publickey, &packets, &list_end);
 326                 publickey->next = next;
 327
 328                 write_openpgp_stream(file_putchar, &fd, packets);
 329                 close(fd);
 330                 free_packet_list(packets);
 331                 packets = NULL;
 332                 ret = 1;
 333         }
 334
 335         if (ret) {
 336                 wl = wordlist = makewordlistfromkey(wordlist, publickey);
 337                 while (wl) {
 338                         uint32_t hash = calchash((uint8_t *) (wl->object));
 339                         prove_path_to(hash, "words");
 340
 341                         worddir(wbuffer, sizeof(wbuffer), wl->object, hash);
 342                         mkdir(wbuffer, 0777);
 343                         wordpath(wbuffer, sizeof(wbuffer), wl->object, hash,
 344                                 keyid);
 345                         link(buffer, wbuffer);
 346
 347                         wl = wl->next;
 348                 }
 349                 llfree(wordlist, free);
 350
 351                 subkeyids = keysubkeys(publickey);
 352                 i = 0;
 353                 while (subkeyids != NULL && subkeyids[i] != 0) {
 354                         prove_path_to(subkeyids[i], "subkeys");
 355
 356                         subkeydir(wbuffer, sizeof(wbuffer), subkeyids[i]);
 357                         mkdir(wbuffer, 0777);
 358                         subkeypath(wbuffer, sizeof(wbuffer), subkeyids[i],
 359                                 keyid);
 360                         link(buffer, wbuffer);
 361
 362                         i++;
 363                 }
 364                 if (subkeyids != NULL) {
 365                         free(subkeyids);
 366                         subkeyids = NULL;
 367                 }
 368         }
 369
 370         if (!intrans)
 371                 fs_endtrans();
 372         return ret;
 373 }
 374
 375 /**
 376  *      delete_key - Given a keyid delete the key from storage.
 377  *      @keyid: The keyid to delete.
 378  *      @intrans: If we're already in a transaction.
 379  */
 380 static int fs_delete_key(uint64_t keyid, bool intrans)
 381 {
 382         static char buffer[PATH_MAX];
 383         int ret;
 384         struct openpgp_publickey *pk = NULL;
 385         struct ll *wordlist = NULL, *wl = NULL;
 386         uint64_t *subkeyids = NULL;
 387         int i = 0;
 388
 389         if ((keyid >> 32) == 0)
 390                 keyid = fs_getfullkeyid(keyid);
 391
 392         if (!intrans)
 393                 fs_starttrans();
 394
 395         ret = fs_fetch_key(keyid, &pk, true);
 396
 397         if (ret) {
 398                 logthing(LOGTHING_DEBUG, "Wordlist for key %016" PRIX64,
 399                          keyid);
 400                 wl = wordlist = makewordlistfromkey(wordlist, pk);
 401                 logthing(LOGTHING_DEBUG,
 402                          "Wordlist for key %016" PRIX64 " done", keyid);
 403                 while (wl) {
 404                         uint32_t hash = calchash((uint8_t *) (wl->object));
 405                         prove_path_to(hash, "words");
 406
 407                         wordpath(buffer, sizeof(buffer), wl->object, hash,
 408                                 keyid);
 409                         unlink(buffer);
 410
 411                         wl = wl->next;
 412                 }
 413
 414                 subkeyids = keysubkeys(pk);
 415                 i = 0;
 416                 while (subkeyids != NULL && subkeyids[i] != 0) {
 417                         prove_path_to(subkeyids[i], "subkeys");
 418
 419                         subkeypath(buffer, sizeof(buffer), subkeyids[i],
 420                                 keyid);
 421                         unlink(buffer);
 422
 423                         i++;
 424                 }
 425                 if (subkeyids != NULL) {
 426                         free(subkeyids);
 427                         subkeyids = NULL;
 428                 }
 429
 430         }
 431
 432         keypath(buffer, sizeof(buffer), keyid);
 433         unlink(buffer);
 434
 435         if (!intrans)
 436                 fs_endtrans();
 437         return 1;
 438 }
 439
 440 static struct ll *internal_get_key_by_word(char *word, struct ll *mct)
 441 {
 442         struct ll *keys = NULL;
 443         DIR *d = NULL;
 444         char buffer[PATH_MAX];
 445         uint32_t hash = calchash((uint8_t *) (word));
 446         struct dirent *de;
 447
 448         worddir(buffer, sizeof(buffer), word, hash);
 449         d = opendir(buffer);
 450         logthing(LOGTHING_DEBUG, "Scanning for word %s in dir %s", word,
 451                  buffer);
 452         if (d)
 453                 do {
 454                         de = readdir(d);
 455                         if (de && de->d_name[0] != '.') {
 456                                 if ((!mct)
 457                                     || (llfind(mct, de->d_name,
 458                                         (int (*)(const void *, const void *))
 459                                                     strcmp) !=
 460                                         NULL)) {
 461                                         logthing(LOGTHING_DEBUG,
 462                                                  "Found %s // %s", word,
 463                                                  de->d_name);
 464                                         keys =
 465                                             lladd(keys,
 466                                                   strdup(de->d_name));
 467                                 }
 468                         }
 469                 } while (de);
 470         closedir(d);
 471
 472         return keys;
 473 }
 474
 475 /*
 476  *      fetch_key_text - Trys to find the keys that contain the supplied text.
 477  *      @search: The text to search for.
 478  *      @publickey: A pointer to a structure to return the key in.
 479  */
 480 static int fs_fetch_key_text(const char *search,
 481                    struct openpgp_publickey **publickey)
 482 {
 483         struct ll *wordlist = NULL, *wl = NULL;
 484         struct ll *keylist = NULL;
 485         char      *searchtext = NULL;
 486         int addedkeys = 0;
 487
 488         logthing(LOGTHING_DEBUG, "Search was '%s'", search);
 489
 490         searchtext = strdup(search);
 491         wl = wordlist = makewordlist(wordlist, searchtext);
 492
 493         keylist = internal_get_key_by_word(wordlist->object, NULL);
 494
 495         if (!keylist) {
 496                 llfree(wordlist, NULL);
 497                 free(searchtext);
 498                 searchtext = NULL;
 499                 return 0;
 500         }
 501
 502         wl = wl->next;
 503         while (wl) {
 504                 struct ll *nkl =
 505                     internal_get_key_by_word(wl->object, keylist);
 506                 if (!nkl) {
 507                         llfree(wordlist, NULL);
 508                         llfree(keylist, free);
 509                         free(searchtext);
 510                         searchtext = NULL;
 511                         return 0;
 512                 }
 513                 llfree(keylist, free);
 514                 keylist = nkl;
 515                 wl = wl->next;
 516         }
 517
 518         llfree(wordlist, NULL);
 519
 520         /* Now add the keys... */
 521         wl = keylist;
 522         while (wl) {
 523                 logthing(LOGTHING_DEBUG, "Adding key: %s", wl->object);
 524                 addedkeys +=
 525                     fs_fetch_key(strtoull(wl->object, NULL, 16), publickey,
 526                               false);
 527                 if (addedkeys >= config.maxkeys)
 528                         break;
 529                 wl = wl->next;
 530         }
 531
 532         llfree(keylist, free);
 533         free(searchtext);
 534         searchtext = NULL;
 535
 536         return addedkeys;
 537 }
 538
 539 /**
 540  *      iterate_keys - call a function once for each key in the db.
 541  *      @iterfunc: The function to call.
 542  *      @ctx: A context pointer
 543  *
 544  *      Calls iterfunc once for each key in the database. ctx is passed
 545  *      unaltered to iterfunc. This function is intended to aid database dumps
 546  *      and statistic calculations.
 547  *
 548  *      Returns the number of keys we iterated over.
 549  */
 550 static int fs_iterate_keys(void (*iterfunc)(void *ctx,
 551                 struct openpgp_publickey *key), void *ctx)
 552 {
 553         return 0;
 554 }
 555
 556 /*
 557  * Include the basic keydb routines.
 558  */
 559 #define NEED_KEYID2UID 1
 560 #define NEED_GETKEYSIGS 1
 561 #define NEED_UPDATEKEYS 1
 562 #include "keydb.c"
 563
 564 struct dbfuncs keydb_fs_funcs = {
 565         .initdb                 = fs_initdb,
 566         .cleanupdb              = fs_cleanupdb,
 567         .starttrans             = fs_starttrans,
 568         .endtrans               = fs_endtrans,
 569         .fetch_key              = fs_fetch_key,
 570         .fetch_key_text         = fs_fetch_key_text,
 571         .store_key              = fs_store_key,
 572         .update_keys            = generic_update_keys,
 573         .delete_key             = fs_delete_key,
 574         .getkeysigs             = generic_getkeysigs,
 575         .cached_getkeysigs      = generic_cached_getkeysigs,
 576         .keyid2uid              = generic_keyid2uid,
 577         .getfullkeyid           = fs_getfullkeyid,
 578         .iterate_keys           = fs_iterate_keys,
 579 };