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_id(uint64_t keyid,
 289               struct openpgp_publickey **publickey,
 290               bool intrans)
 291 {
 292         static char buffer[PATH_MAX];
 293         int ret = 0, fd;
 294         struct openpgp_packet_list *packets = NULL;
 295
 296         if (!intrans)
 297                 fs_starttrans();
 298
 299         if ((keyid >> 32) == 0)
 300                 keyid = fs_getfullkeyid(keyid);
 301
 302         keypath(buffer, sizeof(buffer), keyid);
 303         if ((fd = open(buffer, O_RDONLY)) != -1) {
 304                 /* File is present, load it in... */
 305                 read_openpgp_stream(file_fetchchar, &fd, &packets, 0);
 306                 parse_keys(packets, publickey);
 307                 free_packet_list(packets);
 308                 packets = NULL;
 309                 close(fd);
 310                 ret = 1;
 311         }
 312
 313         if (!intrans)
 314                 fs_endtrans();
 315         return ret;
 316 }
 317
 318 /**
 319  *      store_key - Takes a key and stores it.
 320  *      @publickey: A pointer to the public key to store.
 321  *      @intrans: If we're already in a transaction.
 322  *      @update: If true the key exists and should be updated.
 323  */
 324 static int fs_store_key(struct openpgp_publickey *publickey, bool intrans,
 325               bool update)
 326 {
 327         static char buffer[PATH_MAX];
 328         static char wbuffer[PATH_MAX];
 329         int ret = 0, fd;
 330         struct openpgp_packet_list *packets = NULL;
 331         struct openpgp_packet_list *list_end = NULL;
 332         struct openpgp_publickey *next = NULL;
 333         uint64_t keyid;
 334         struct ll *wordlist = NULL, *wl = NULL;
 335         struct skshash hash;
 336         uint64_t *subkeyids = NULL;
 337         uint32_t hashid;
 338         int i = 0;
 339
 340         if (get_keyid(publickey, &keyid) != ONAK_E_OK) {
 341                 logthing(LOGTHING_ERROR, "Couldn't find key ID for key.");
 342                 return 0;
 343         }
 344
 345         if (!intrans)
 346                 fs_starttrans();
 347
 348         prove_path_to(keyid, "key");
 349         keypath(buffer, sizeof(buffer), keyid);
 350
 351         if ((fd =
 352              open(buffer, O_WRONLY | (update ? O_TRUNC : O_CREAT),
 353                   0644)) != -1) {
 354                 next = publickey->next;
 355                 publickey->next = NULL;
 356                 flatten_publickey(publickey, &packets, &list_end);
 357                 publickey->next = next;
 358
 359                 write_openpgp_stream(file_putchar, &fd, packets);
 360                 close(fd);
 361                 free_packet_list(packets);
 362                 packets = NULL;
 363                 ret = 1;
 364         }
 365
 366         if (ret) {
 367                 wl = wordlist = makewordlistfromkey(wordlist, publickey);
 368                 while (wl) {
 369                         uint32_t hash = calchash((uint8_t *) (wl->object));
 370                         prove_path_to(hash, "words");
 371
 372                         worddir(wbuffer, sizeof(wbuffer), wl->object, hash);
 373                         mkdir(wbuffer, 0777);
 374                         wordpath(wbuffer, sizeof(wbuffer), wl->object, hash,
 375                                 keyid);
 376                         link(buffer, wbuffer);
 377
 378                         wl = wl->next;
 379                 }
 380                 llfree(wordlist, free);
 381
 382                 subkeyids = keysubkeys(publickey);
 383                 i = 0;
 384                 while (subkeyids != NULL && subkeyids[i] != 0) {
 385                         prove_path_to(subkeyids[i], "subkeys");
 386
 387                         subkeydir(wbuffer, sizeof(wbuffer), subkeyids[i]);
 388                         mkdir(wbuffer, 0777);
 389                         subkeypath(wbuffer, sizeof(wbuffer), subkeyids[i],
 390                                 keyid);
 391                         link(buffer, wbuffer);
 392
 393                         i++;
 394                 }
 395                 if (subkeyids != NULL) {
 396                         free(subkeyids);
 397                         subkeyids = NULL;
 398                 }
 399
 400                 get_skshash(publickey, &hash);
 401                 hashid = (hash.hash[0] << 24) + (hash.hash[1] << 16) +
 402                                 (hash.hash[2] << 8) + hash.hash[3];
 403                 prove_path_to(hashid, "skshash");
 404                 skshashpath(wbuffer, sizeof(wbuffer), &hash);
 405                 link(buffer, wbuffer);
 406         }
 407
 408         if (!intrans)
 409                 fs_endtrans();
 410         return ret;
 411 }
 412
 413 /**
 414  *      delete_key - Given a keyid delete the key from storage.
 415  *      @keyid: The keyid to delete.
 416  *      @intrans: If we're already in a transaction.
 417  */
 418 static int fs_delete_key(uint64_t keyid, bool intrans)
 419 {
 420         static char buffer[PATH_MAX];
 421         int ret;
 422         struct openpgp_publickey *pk = NULL;
 423         struct skshash hash;
 424         struct ll *wordlist = NULL, *wl = NULL;
 425         uint64_t *subkeyids = NULL;
 426         int i = 0;
 427
 428         if ((keyid >> 32) == 0)
 429                 keyid = fs_getfullkeyid(keyid);
 430
 431         if (!intrans)
 432                 fs_starttrans();
 433
 434         ret = fs_fetch_key_id(keyid, &pk, true);
 435
 436         if (ret) {
 437                 logthing(LOGTHING_DEBUG, "Wordlist for key %016" PRIX64,
 438                          keyid);
 439                 wl = wordlist = makewordlistfromkey(wordlist, pk);
 440                 logthing(LOGTHING_DEBUG,
 441                          "Wordlist for key %016" PRIX64 " done", keyid);
 442                 while (wl) {
 443                         uint32_t hash = calchash((uint8_t *) (wl->object));
 444                         prove_path_to(hash, "words");
 445
 446                         wordpath(buffer, sizeof(buffer), wl->object, hash,
 447                                 keyid);
 448                         unlink(buffer);
 449
 450                         wl = wl->next;
 451                 }
 452
 453                 subkeyids = keysubkeys(pk);
 454                 i = 0;
 455                 while (subkeyids != NULL && subkeyids[i] != 0) {
 456                         prove_path_to(subkeyids[i], "subkeys");
 457
 458                         subkeypath(buffer, sizeof(buffer), subkeyids[i],
 459                                 keyid);
 460                         unlink(buffer);
 461
 462                         i++;
 463                 }
 464                 if (subkeyids != NULL) {
 465                         free(subkeyids);
 466                         subkeyids = NULL;
 467                 }
 468
 469                 get_skshash(pk, &hash);
 470                 skshashpath(buffer, sizeof(buffer), &hash);
 471                 unlink(buffer);
 472         }
 473
 474         keypath(buffer, sizeof(buffer), keyid);
 475         unlink(buffer);
 476
 477         if (!intrans)
 478                 fs_endtrans();
 479         return 1;
 480 }
 481
 482 static struct ll *internal_get_key_by_word(char *word, struct ll *mct)
 483 {
 484         struct ll *keys = NULL;
 485         DIR *d = NULL;
 486         char buffer[PATH_MAX];
 487         uint32_t hash = calchash((uint8_t *) (word));
 488         struct dirent *de;
 489
 490         worddir(buffer, sizeof(buffer), word, hash);
 491         d = opendir(buffer);
 492         logthing(LOGTHING_DEBUG, "Scanning for word %s in dir %s", word,
 493                  buffer);
 494         if (d)
 495                 do {
 496                         de = readdir(d);
 497                         if (de && de->d_name[0] != '.') {
 498                                 if ((!mct)
 499                                     || (llfind(mct, de->d_name,
 500                                         (int (*)(const void *, const void *))
 501                                                     strcmp) !=
 502                                         NULL)) {
 503                                         logthing(LOGTHING_DEBUG,
 504                                                  "Found %s // %s", word,
 505                                                  de->d_name);
 506                                         keys =
 507                                             lladd(keys,
 508                                                   strdup(de->d_name));
 509                                 }
 510                         }
 511                 } while (de);
 512         closedir(d);
 513
 514         return keys;
 515 }
 516
 517 /*
 518  *      fetch_key_text - Trys to find the keys that contain the supplied text.
 519  *      @search: The text to search for.
 520  *      @publickey: A pointer to a structure to return the key in.
 521  */
 522 static int fs_fetch_key_text(const char *search,
 523                    struct openpgp_publickey **publickey)
 524 {
 525         struct ll *wordlist = NULL, *wl = NULL;
 526         struct ll *keylist = NULL;
 527         char      *searchtext = NULL;
 528         int addedkeys = 0;
 529
 530         logthing(LOGTHING_DEBUG, "Search was '%s'", search);
 531
 532         searchtext = strdup(search);
 533         wl = wordlist = makewordlist(wordlist, searchtext);
 534
 535         keylist = internal_get_key_by_word(wordlist->object, NULL);
 536
 537         if (!keylist) {
 538                 llfree(wordlist, NULL);
 539                 free(searchtext);
 540                 searchtext = NULL;
 541                 return 0;
 542         }
 543
 544         wl = wl->next;
 545         while (wl) {
 546                 struct ll *nkl =
 547                     internal_get_key_by_word(wl->object, keylist);
 548                 if (!nkl) {
 549                         llfree(wordlist, NULL);
 550                         llfree(keylist, free);
 551                         free(searchtext);
 552                         searchtext = NULL;
 553                         return 0;
 554                 }
 555                 llfree(keylist, free);
 556                 keylist = nkl;
 557                 wl = wl->next;
 558         }
 559
 560         llfree(wordlist, NULL);
 561
 562         /* Now add the keys... */
 563         wl = keylist;
 564         while (wl) {
 565                 logthing(LOGTHING_DEBUG, "Adding key: %s", wl->object);
 566                 addedkeys +=
 567                     fs_fetch_key_id(strtoull(wl->object, NULL, 16), publickey,
 568                               false);
 569                 if (addedkeys >= config.maxkeys)
 570                         break;
 571                 wl = wl->next;
 572         }
 573
 574         llfree(keylist, free);
 575         free(searchtext);
 576         searchtext = NULL;
 577
 578         return addedkeys;
 579 }
 580
 581 /**
 582  *      fetch_key_skshash - Given an SKS hash fetch the key from storage.
 583  *      @hash: The hash to fetch.
 584  *      @publickey: A pointer to a structure to return the key in.
 585  *      @intrans: If we're already in a transaction.
 586  */
 587 static int fs_fetch_key_skshash(const struct skshash *hash,
 588               struct openpgp_publickey **publickey)
 589 {
 590         static char buffer[PATH_MAX];
 591         int ret = 0, fd;
 592         struct openpgp_packet_list *packets = NULL;
 593
 594         skshashpath(buffer, sizeof(buffer), hash);
 595         if ((fd = open(buffer, O_RDONLY)) != -1) {
 596                 read_openpgp_stream(file_fetchchar, &fd, &packets, 0);
 597                 parse_keys(packets, publickey);
 598                 free_packet_list(packets);
 599                 packets = NULL;
 600                 close(fd);
 601                 ret = 1;
 602         }
 603
 604         return ret;
 605 }
 606
 607 /**
 608  *      iterate_keys - call a function once for each key in the db.
 609  *      @iterfunc: The function to call.
 610  *      @ctx: A context pointer
 611  *
 612  *      Calls iterfunc once for each key in the database. ctx is passed
 613  *      unaltered to iterfunc. This function is intended to aid database dumps
 614  *      and statistic calculations.
 615  *
 616  *      Returns the number of keys we iterated over.
 617  */
 618 static int fs_iterate_keys(void (*iterfunc)(void *ctx,
 619                 struct openpgp_publickey *key), void *ctx)
 620 {
 621         return 0;
 622 }
 623
 624 /*
 625  * Include the basic keydb routines.
 626  */
 627 #define NEED_KEYID2UID 1
 628 #define NEED_GETKEYSIGS 1
 629 #define NEED_UPDATEKEYS 1
 630 #define NEED_GET_FP 1
 631 #include "keydb.c"
 632
 633 struct dbfuncs keydb_fs_funcs = {
 634         .initdb                 = fs_initdb,
 635         .cleanupdb              = fs_cleanupdb,
 636         .starttrans             = fs_starttrans,
 637         .endtrans               = fs_endtrans,
 638         .fetch_key_id           = fs_fetch_key_id,
 639         .fetch_key_fp           = generic_fetch_key_fp,
 640         .fetch_key_text         = fs_fetch_key_text,
 641         .fetch_key_skshash      = fs_fetch_key_skshash,
 642         .store_key              = fs_store_key,
 643         .update_keys            = generic_update_keys,
 644         .delete_key             = fs_delete_key,
 645         .getkeysigs             = generic_getkeysigs,
 646         .cached_getkeysigs      = generic_cached_getkeysigs,
 647         .keyid2uid              = generic_keyid2uid,
 648         .getfullkeyid           = fs_getfullkeyid,
 649         .iterate_keys           = fs_iterate_keys,
 650 };