keydb_fs.c

   1 /*
   2  * keydb_fs.c - Routines to store and fetch keys in a filesystem hierarchy.
   3  *
   4  * Copyright 2004 Daniel Silverstone <dsilvers@digital-scurf.org>
   5  *
   6  * This program is free software: you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the Free
   8  * Software Foundation; version 2 of the License.
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along with
  16  * this program; if not, write to the Free Software Foundation, Inc., 51
  17  * Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  */
  19
  20 #include <sys/types.h>
  21 #include <sys/uio.h>
  22 #include <sys/stat.h>
  23 #include <errno.h>
  24 #include <fcntl.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <unistd.h>
  29 #include <limits.h>
  30 #include <dirent.h>
  31
  32 #include "charfuncs.h"
  33 #include "decodekey.h"
  34 #include "keydb.h"
  35 #include "keyid.h"
  36 #include "keystructs.h"
  37 #include "ll.h"
  38 #include "mem.h"
  39 #include "onak-conf.h"
  40 #include "parsekey.h"
  41 #include "log.h"
  42 #include "wordlist.h"
  43
  44 /* Hack: We should really dynamically allocate our path buffers */
  45 #ifndef PATH_MAX
  46 #define PATH_MAX 1024
  47 #endif
  48
  49 static int keydb_lockfile_fd = -1;
  50 static bool keydb_lockfile_readonly;
  51
  52 /*****************************************************************************/
  53
  54 /* Helper functions */
  55
  56 #define FNV_offset_basis 2166136261ul
  57 #define FNV_mixing_prime 16777619ul
  58
  59 static uint32_t calchash(uint8_t * ptr)
  60 {
  61         register uint32_t h = FNV_offset_basis;
  62         register uint32_t p = FNV_mixing_prime;
  63         register uint32_t n = strlen((char *) ptr);
  64         register uint8_t *c = ptr;
  65         while (n--) {
  66                 h *= p;
  67                 h ^= *c++;
  68         }
  69         return h ? h : 1;       /* prevent a hash of zero happening */
  70 }
  71
  72
  73 static void keypath(char *buffer, size_t length, uint64_t _keyid)
  74 {
  75         uint64_t keyid = _keyid << 32;
  76         snprintf(buffer, length, "%s/key/%02X/%02X/%08X/%016" PRIX64,
  77                  config.db_dir, (uint8_t) ((keyid >> 56) & 0xFF),
  78                  (uint8_t) ((keyid >> 48) & 0xFF),
  79                  (uint32_t) (keyid >> 32), _keyid);
  80 }
  81
  82 static void keydir(char *buffer, size_t length, uint64_t _keyid)
  83 {
  84         uint64_t keyid = _keyid << 32;
  85         snprintf(buffer, length, "%s/key/%02X/%02X/%08X", config.db_dir,
  86                  (uint8_t) ((keyid >> 56) & 0xFF),
  87                  (uint8_t) ((keyid >> 48) & 0xFF),
  88                  (uint32_t) (keyid >> 32));
  89 }
  90
  91 static void prove_path_to(uint64_t keyid, char *what)
  92 {
  93         static char buffer[PATH_MAX];
  94         snprintf(buffer, sizeof(buffer), "%s/%s", config.db_dir, what);
  95         mkdir(buffer, 0777);
  96
  97         snprintf(buffer, sizeof(buffer), "%s/%s/%02X", config.db_dir, what,
  98                  (uint8_t) ((keyid >> 24) & 0xFF));
  99         mkdir(buffer, 0777);
 100
 101         snprintf(buffer, sizeof(buffer), "%s/%s/%02X/%02X", config.db_dir,
 102                  what,
 103                  (uint8_t) ((keyid >> 24) & 0xFF),
 104                  (uint8_t) ((keyid >> 16) & 0xFF));
 105         mkdir(buffer, 0777);
 106
 107         snprintf(buffer, sizeof(buffer), "%s/%s/%02X/%02X/%08X", config.db_dir,
 108                  what,
 109                  (uint8_t) ((keyid >> 24) & 0xFF),
 110                  (uint8_t) ((keyid >> 16) & 0xFF), (uint32_t) (keyid));
 111         mkdir(buffer, 0777);
 112 }
 113
 114 static void wordpath(char *buffer, size_t length, char *word, uint32_t hash,
 115                 uint64_t keyid)
 116 {
 117         snprintf(buffer, length, "%s/words/%02X/%02X/%08X/%s/%016" PRIX64,
 118                  config.db_dir, (uint8_t) ((hash >> 24) & 0xFF),
 119                  (uint8_t) ((hash >> 16) & 0xFF), hash, word, keyid);
 120 }
 121
 122 static void worddir(char *buffer, size_t length, char *word, uint32_t hash)
 123 {
 124         snprintf(buffer, length, "%s/words/%02X/%02X/%08X/%s", config.db_dir,
 125                  (uint8_t) ((hash >> 24) & 0xFF),
 126                  (uint8_t) ((hash >> 16) & 0xFF), hash, word);
 127 }
 128
 129 static void subkeypath(char *buffer, size_t length, uint64_t subkey,
 130                 uint64_t keyid)
 131 {
 132         snprintf(buffer, length, "%s/subkeys/%02X/%02X/%08X/%016" PRIX64,
 133                  config.db_dir,
 134                  (uint8_t) ((subkey >> 24) & 0xFF),
 135                  (uint8_t) ((subkey >> 16) & 0xFF),
 136                  (uint32_t) (subkey & 0xFFFFFFFF),
 137                  keyid);
 138 }
 139
 140 static void skshashpath(char *buffer, size_t length,
 141                 const struct skshash *hash)
 142 {
 143         snprintf(buffer, length, "%s/skshash/%02X/%02X/%02X%02X%02X%02X/"
 144                 "%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X",
 145                  config.db_dir,
 146                  hash->hash[0], hash->hash[1],
 147                  hash->hash[0], hash->hash[1], hash->hash[2], hash->hash[3],
 148                  hash->hash[4], hash->hash[5], hash->hash[6], hash->hash[7],
 149                  hash->hash[8], hash->hash[9], hash->hash[10], hash->hash[11],
 150                  hash->hash[12], hash->hash[13], hash->hash[14],
 151                  hash->hash[15]);
 152 }
 153 static void subkeydir(char *buffer, size_t length, uint64_t subkey)
 154 {
 155         snprintf(buffer, length, "%s/subkeys/%02X/%02X/%08X",
 156                  config.db_dir,
 157                  (uint8_t) ((subkey >> 24) & 0xFF),
 158                  (uint8_t) ((subkey >> 16) & 0xFF),
 159                  (uint32_t) (subkey & 0xFFFFFFFF));
 160 }
 161
 162 /*****************************************************************************/
 163
 164 /**
 165  *      initdb - Initialize the key database.
 166  */
 167 static void fs_initdb(bool readonly)
 168 {
 169         char buffer[PATH_MAX];
 170
 171         keydb_lockfile_readonly = readonly;
 172
 173         snprintf(buffer, sizeof(buffer), "%s/.lock", config.db_dir);
 174
 175         if (access(config.db_dir, R_OK | W_OK | X_OK) == -1) {
 176                 if (errno != ENOENT) {
 177                         logthing(LOGTHING_CRITICAL,
 178                                  "Unable to access keydb_fs root of '%s'. (%s)",
 179                                  config.db_dir, strerror(errno));
 180                         exit(1);        /* Lacking rwx on the key dir */
 181                 }
 182                 mkdir(config.db_dir, 0777);
 183                 keydb_lockfile_fd = open(buffer, O_RDWR | O_CREAT, 0600);
 184         }
 185         chdir(config.db_dir);
 186         if (keydb_lockfile_fd == -1)
 187                 keydb_lockfile_fd = open(buffer,
 188                                          (keydb_lockfile_readonly) ?
 189                                          O_RDONLY : O_RDWR);
 190         if (keydb_lockfile_fd == -1)
 191                 keydb_lockfile_fd = open(buffer, O_RDWR | O_CREAT, 0600);
 192         if (keydb_lockfile_fd == -1) {
 193                 logthing(LOGTHING_CRITICAL,
 194                          "Unable to open lockfile '%s'. (%s)",
 195                          buffer, strerror(errno));
 196                 exit(1);        /* Lacking rwx on the key dir */
 197         }
 198 }
 199
 200 /**
 201  *      cleanupdb - De-initialize the key database.
 202  */
 203 static void fs_cleanupdb(void)
 204 {
 205         /* Mmmm nothing to do here? */
 206         close(keydb_lockfile_fd);
 207 }
 208
 209 /**
 210  *      starttrans - Start a transaction.
 211  */
 212 static bool fs_starttrans(void)
 213 {
 214         struct flock lockstruct;
 215         int remaining = 20;
 216         lockstruct.l_type =
 217             F_RDLCK | ((keydb_lockfile_readonly) ? 0 : F_WRLCK);
 218         lockstruct.l_whence = SEEK_SET;
 219         lockstruct.l_start = 0;
 220         lockstruct.l_len = 1;
 221
 222         while (fcntl(keydb_lockfile_fd, F_SETLK, &lockstruct) == -1) {
 223                 if (remaining-- == 0)
 224                         return false;   /* Hope to hell that noodles DTRT */
 225                 usleep(100);
 226         }
 227         return true;
 228 }
 229
 230 /**
 231  *      endtrans - End a transaction.
 232  */
 233 static void fs_endtrans(void)
 234 {
 235         struct flock lockstruct;
 236
 237         lockstruct.l_type = F_UNLCK;
 238         lockstruct.l_whence = SEEK_SET;
 239         lockstruct.l_start = 0;
 240         lockstruct.l_len = 1;
 241         fcntl(keydb_lockfile_fd, F_SETLK, &lockstruct);
 242 }
 243
 244 static uint64_t fs_getfullkeyid(uint64_t keyid)
 245 {
 246         static char buffer[PATH_MAX];
 247         DIR *d = NULL;
 248         struct dirent *de = NULL;
 249         uint64_t ret = 0;
 250
 251         keydir(buffer, sizeof(buffer), keyid);
 252
 253         d = opendir(buffer);
 254         if (d) {
 255                 do {
 256                         de = readdir(d);
 257                         if (de && de->d_name[0] != '.') {
 258                                 ret = strtoull(de->d_name, NULL, 16);
 259                         }
 260                 } while (de && de->d_name[0] == '.');
 261                 closedir(d);
 262         }
 263
 264         if (ret == 0) {
 265                 subkeydir(buffer, sizeof(buffer), keyid);
 266
 267                 d = opendir(buffer);
 268                 if (d) {
 269                         do {
 270                                 de = readdir(d);
 271                                 if (de && de->d_name[0] != '.') {
 272                                         ret = strtoull(de->d_name, NULL, 16);
 273                                 }
 274                         } while (de && de->d_name[0] == '.');
 275                         closedir(d);
 276                 }
 277         }
 278
 279         return ret;
 280 }
 281
 282 /**
 283  *      fetch_key - Given a keyid fetch the key from storage.
 284  *      @keyid: The keyid to fetch.
 285  *      @publickey: A pointer to a structure to return the key in.
 286  *      @intrans: If we're already in a transaction.
 287  */
 288 static int fs_fetch_key(uint64_t keyid, struct openpgp_publickey **publickey,
 289               bool intrans)
 290 {
 291         static char buffer[PATH_MAX];
 292         int ret = 0, fd;
 293         struct openpgp_packet_list *packets = NULL;
 294
 295         if (!intrans)
 296                 fs_starttrans();
 297
 298         if ((keyid >> 32) == 0)
 299                 keyid = fs_getfullkeyid(keyid);
 300
 301         keypath(buffer, sizeof(buffer), keyid);
 302         if ((fd = open(buffer, O_RDONLY)) != -1) {
 303                 /* File is present, load it in... */
 304                 read_openpgp_stream(file_fetchchar, &fd, &packets, 0);
 305                 parse_keys(packets, publickey);
 306                 free_packet_list(packets);
 307                 packets = NULL;
 308                 close(fd);
 309                 ret = 1;
 310         }
 311
 312         if (!intrans)
 313                 fs_endtrans();
 314         return ret;
 315 }
 316
 317 /**
 318  *      store_key - Takes a key and stores it.
 319  *      @publickey: A pointer to the public key to store.
 320  *      @intrans: If we're already in a transaction.
 321  *      @update: If true the key exists and should be updated.
 322  */
 323 static int fs_store_key(struct openpgp_publickey *publickey, bool intrans,
 324               bool update)
 325 {
 326         static char buffer[PATH_MAX];
 327         static char wbuffer[PATH_MAX];
 328         int ret = 0, fd;
 329         struct openpgp_packet_list *packets = NULL;
 330         struct openpgp_packet_list *list_end = NULL;
 331         struct openpgp_publickey *next = NULL;
 332         uint64_t keyid;
 333         struct ll *wordlist = NULL, *wl = NULL;
 334         struct skshash hash;
 335         uint64_t *subkeyids = NULL;
 336         uint32_t hashid;
 337         int i = 0;
 338
 339         get_keyid(publickey, &keyid);
 340
 341         if (!intrans)
 342                 fs_starttrans();
 343
 344         prove_path_to(keyid, "key");
 345         keypath(buffer, sizeof(buffer), keyid);
 346
 347         if ((fd =
 348              open(buffer, O_WRONLY | (update ? O_TRUNC : O_CREAT),
 349                   0644)) != -1) {
 350                 next = publickey->next;
 351                 publickey->next = NULL;
 352                 flatten_publickey(publickey, &packets, &list_end);
 353                 publickey->next = next;
 354
 355                 write_openpgp_stream(file_putchar, &fd, packets);
 356                 close(fd);
 357                 free_packet_list(packets);
 358                 packets = NULL;
 359                 ret = 1;
 360         }
 361
 362         if (ret) {
 363                 wl = wordlist = makewordlistfromkey(wordlist, publickey);
 364                 while (wl) {
 365                         uint32_t hash = calchash((uint8_t *) (wl->object));
 366                         prove_path_to(hash, "words");
 367
 368                         worddir(wbuffer, sizeof(wbuffer), wl->object, hash);
 369                         mkdir(wbuffer, 0777);
 370                         wordpath(wbuffer, sizeof(wbuffer), wl->object, hash,
 371                                 keyid);
 372                         link(buffer, wbuffer);
 373
 374                         wl = wl->next;
 375                 }
 376                 llfree(wordlist, free);
 377
 378                 subkeyids = keysubkeys(publickey);
 379                 i = 0;
 380                 while (subkeyids != NULL && subkeyids[i] != 0) {
 381                         prove_path_to(subkeyids[i], "subkeys");
 382
 383                         subkeydir(wbuffer, sizeof(wbuffer), subkeyids[i]);
 384                         mkdir(wbuffer, 0777);
 385                         subkeypath(wbuffer, sizeof(wbuffer), subkeyids[i],
 386                                 keyid);
 387                         link(buffer, wbuffer);
 388
 389                         i++;
 390                 }
 391                 if (subkeyids != NULL) {
 392                         free(subkeyids);
 393                         subkeyids = NULL;
 394                 }
 395
 396                 get_skshash(publickey, &hash);
 397                 hashid = (hash.hash[0] << 24) + (hash.hash[1] << 16) +
 398                                 (hash.hash[2] << 8) + hash.hash[3];
 399                 prove_path_to(hashid, "skshash");
 400                 skshashpath(wbuffer, sizeof(wbuffer), &hash);
 401                 link(buffer, wbuffer);
 402         }
 403
 404         if (!intrans)
 405                 fs_endtrans();
 406         return ret;
 407 }
 408
 409 /**
 410  *      delete_key - Given a keyid delete the key from storage.
 411  *      @keyid: The keyid to delete.
 412  *      @intrans: If we're already in a transaction.
 413  */
 414 static int fs_delete_key(uint64_t keyid, bool intrans)
 415 {
 416         static char buffer[PATH_MAX];
 417         int ret;
 418         struct openpgp_publickey *pk = NULL;
 419         struct skshash hash;
 420         struct ll *wordlist = NULL, *wl = NULL;
 421         uint64_t *subkeyids = NULL;
 422         int i = 0;
 423
 424         if ((keyid >> 32) == 0)
 425                 keyid = fs_getfullkeyid(keyid);
 426
 427         if (!intrans)
 428                 fs_starttrans();
 429
 430         ret = fs_fetch_key(keyid, &pk, true);
 431
 432         if (ret) {
 433                 logthing(LOGTHING_DEBUG, "Wordlist for key %016" PRIX64,
 434                          keyid);
 435                 wl = wordlist = makewordlistfromkey(wordlist, pk);
 436                 logthing(LOGTHING_DEBUG,
 437                          "Wordlist for key %016" PRIX64 " done", keyid);
 438                 while (wl) {
 439                         uint32_t hash = calchash((uint8_t *) (wl->object));
 440                         prove_path_to(hash, "words");
 441
 442                         wordpath(buffer, sizeof(buffer), wl->object, hash,
 443                                 keyid);
 444                         unlink(buffer);
 445
 446                         wl = wl->next;
 447                 }
 448
 449                 subkeyids = keysubkeys(pk);
 450                 i = 0;
 451                 while (subkeyids != NULL && subkeyids[i] != 0) {
 452                         prove_path_to(subkeyids[i], "subkeys");
 453
 454                         subkeypath(buffer, sizeof(buffer), subkeyids[i],
 455                                 keyid);
 456                         unlink(buffer);
 457
 458                         i++;
 459                 }
 460                 if (subkeyids != NULL) {
 461                         free(subkeyids);
 462                         subkeyids = NULL;
 463                 }
 464
 465                 get_skshash(pk, &hash);
 466                 skshashpath(buffer, sizeof(buffer), &hash);
 467                 unlink(buffer);
 468         }
 469
 470         keypath(buffer, sizeof(buffer), keyid);
 471         unlink(buffer);
 472
 473         if (!intrans)
 474                 fs_endtrans();
 475         return 1;
 476 }
 477
 478 static struct ll *internal_get_key_by_word(char *word, struct ll *mct)
 479 {
 480         struct ll *keys = NULL;
 481         DIR *d = NULL;
 482         char buffer[PATH_MAX];
 483         uint32_t hash = calchash((uint8_t *) (word));
 484         struct dirent *de;
 485
 486         worddir(buffer, sizeof(buffer), word, hash);
 487         d = opendir(buffer);
 488         logthing(LOGTHING_DEBUG, "Scanning for word %s in dir %s", word,
 489                  buffer);
 490         if (d)
 491                 do {
 492                         de = readdir(d);
 493                         if (de && de->d_name[0] != '.') {
 494                                 if ((!mct)
 495                                     || (llfind(mct, de->d_name,
 496                                         (int (*)(const void *, const void *))
 497                                                     strcmp) !=
 498                                         NULL)) {
 499                                         logthing(LOGTHING_DEBUG,
 500                                                  "Found %s // %s", word,
 501                                                  de->d_name);
 502                                         keys =
 503                                             lladd(keys,
 504                                                   strdup(de->d_name));
 505                                 }
 506                         }
 507                 } while (de);
 508         closedir(d);
 509
 510         return keys;
 511 }
 512
 513 /*
 514  *      fetch_key_text - Trys to find the keys that contain the supplied text.
 515  *      @search: The text to search for.
 516  *      @publickey: A pointer to a structure to return the key in.
 517  */
 518 static int fs_fetch_key_text(const char *search,
 519                    struct openpgp_publickey **publickey)
 520 {
 521         struct ll *wordlist = NULL, *wl = NULL;
 522         struct ll *keylist = NULL;
 523         char      *searchtext = NULL;
 524         int addedkeys = 0;
 525
 526         logthing(LOGTHING_DEBUG, "Search was '%s'", search);
 527
 528         searchtext = strdup(search);
 529         wl = wordlist = makewordlist(wordlist, searchtext);
 530
 531         keylist = internal_get_key_by_word(wordlist->object, NULL);
 532
 533         if (!keylist) {
 534                 llfree(wordlist, NULL);
 535                 free(searchtext);
 536                 searchtext = NULL;
 537                 return 0;
 538         }
 539
 540         wl = wl->next;
 541         while (wl) {
 542                 struct ll *nkl =
 543                     internal_get_key_by_word(wl->object, keylist);
 544                 if (!nkl) {
 545                         llfree(wordlist, NULL);
 546                         llfree(keylist, free);
 547                         free(searchtext);
 548                         searchtext = NULL;
 549                         return 0;
 550                 }
 551                 llfree(keylist, free);
 552                 keylist = nkl;
 553                 wl = wl->next;
 554         }
 555
 556         llfree(wordlist, NULL);
 557
 558         /* Now add the keys... */
 559         wl = keylist;
 560         while (wl) {
 561                 logthing(LOGTHING_DEBUG, "Adding key: %s", wl->object);
 562                 addedkeys +=
 563                     fs_fetch_key(strtoull(wl->object, NULL, 16), publickey,
 564                               false);
 565                 if (addedkeys >= config.maxkeys)
 566                         break;
 567                 wl = wl->next;
 568         }
 569
 570         llfree(keylist, free);
 571         free(searchtext);
 572         searchtext = NULL;
 573
 574         return addedkeys;
 575 }
 576
 577 /**
 578  *      fetch_key_skshash - Given an SKS hash fetch the key from storage.
 579  *      @hash: The hash to fetch.
 580  *      @publickey: A pointer to a structure to return the key in.
 581  *      @intrans: If we're already in a transaction.
 582  */
 583 static int fs_fetch_key_skshash(const struct skshash *hash,
 584               struct openpgp_publickey **publickey)
 585 {
 586         static char buffer[PATH_MAX];
 587         int ret = 0, fd;
 588         struct openpgp_packet_list *packets = NULL;
 589
 590         skshashpath(buffer, sizeof(buffer), hash);
 591         if ((fd = open(buffer, O_RDONLY)) != -1) {
 592                 read_openpgp_stream(file_fetchchar, &fd, &packets, 0);
 593                 parse_keys(packets, publickey);
 594                 free_packet_list(packets);
 595                 packets = NULL;
 596                 close(fd);
 597                 ret = 1;
 598         }
 599
 600         return ret;
 601 }
 602
 603 /**
 604  *      iterate_keys - call a function once for each key in the db.
 605  *      @iterfunc: The function to call.
 606  *      @ctx: A context pointer
 607  *
 608  *      Calls iterfunc once for each key in the database. ctx is passed
 609  *      unaltered to iterfunc. This function is intended to aid database dumps
 610  *      and statistic calculations.
 611  *
 612  *      Returns the number of keys we iterated over.
 613  */
 614 static int fs_iterate_keys(void (*iterfunc)(void *ctx,
 615                 struct openpgp_publickey *key), void *ctx)
 616 {
 617         return 0;
 618 }
 619
 620 /*
 621  * Include the basic keydb routines.
 622  */
 623 #define NEED_KEYID2UID 1
 624 #define NEED_GETKEYSIGS 1
 625 #define NEED_UPDATEKEYS 1
 626 #include "keydb.c"
 627
 628 struct dbfuncs keydb_fs_funcs = {
 629         .initdb                 = fs_initdb,
 630         .cleanupdb              = fs_cleanupdb,
 631         .starttrans             = fs_starttrans,
 632         .endtrans               = fs_endtrans,
 633         .fetch_key              = fs_fetch_key,
 634         .fetch_key_text         = fs_fetch_key_text,
 635         .fetch_key_skshash      = fs_fetch_key_skshash,
 636         .store_key              = fs_store_key,
 637         .update_keys            = generic_update_keys,
 638         .delete_key             = fs_delete_key,
 639         .getkeysigs             = generic_getkeysigs,
 640         .cached_getkeysigs      = generic_cached_getkeysigs,
 641         .keyid2uid              = generic_keyid2uid,
 642         .getfullkeyid           = fs_getfullkeyid,
 643         .iterate_keys           = fs_iterate_keys,
 644 };