keydb_dynamic.c

   1 /*
   2  * keydb_dynamic.c - backend that can load the other backends
   3  *
   4  * Copyright 2005 Brett Parker <iDunno@sommitrealweird.co.uk>
   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 <dlfcn.h>
  21 #include <stdio.h>
  22 #include <string.h>
  23
  24 #include "decodekey.h"
  25 #include "hash.h"
  26 #include "keydb.h"
  27 #include "keyid.h"
  28 #include "keystructs.h"
  29 #include "log.h"
  30 #include "mem.h"
  31 #include "merge.h"
  32 #include "onak-conf.h"
  33 #include "openpgp.h"
  34 #include "parsekey.h"
  35 #include "sendsync.h"
  36
  37 static struct dbfuncs *loaded_backend = NULL;
  38 static void *backend_handle;
  39
  40 static bool close_backend(void)
  41 {
  42         loaded_backend = NULL;
  43         dlclose(backend_handle);
  44         backend_handle = NULL;
  45
  46         return true;
  47 }
  48
  49 static bool load_backend(void)
  50 {
  51         char *soname = NULL;
  52         char *funcsname = NULL;
  53
  54         if (loaded_backend != NULL) {
  55                 close_backend();
  56                 loaded_backend = NULL;
  57         }
  58
  59         if (config.use_keyd) {
  60                 free(config.db_backend);
  61                 config.db_backend = strdup("keyd");
  62         }
  63
  64         if (!config.db_backend) {
  65                 logthing(LOGTHING_CRITICAL, "No database backend defined.");
  66                 exit(EXIT_FAILURE);
  67         }
  68
  69         if (config.backends_dir == NULL) {
  70                 soname = malloc(strlen(config.db_backend)
  71                         + strlen("./libkeydb_")
  72                         + strlen(".so")
  73                         + 1);
  74
  75                 sprintf(soname, "./libkeydb_%s.so", config.db_backend);
  76         } else {
  77                 soname = malloc(strlen(config.db_backend)
  78                         + strlen("/libkeydb_")
  79                         + strlen(".so")
  80                         + strlen(config.backends_dir)
  81                         + 1);
  82
  83                 sprintf(soname, "%s/libkeydb_%s.so", config.backends_dir,
  84                         config.db_backend);
  85         }
  86
  87         logthing(LOGTHING_INFO, "Loading dynamic backend: %s", soname);
  88
  89         backend_handle = dlopen(soname, RTLD_LAZY);
  90         if (backend_handle == NULL) {
  91                 logthing(LOGTHING_CRITICAL,
  92                                 "Failed to open handle to library '%s': %s",
  93                                 soname, dlerror());
  94                 free(soname);
  95                 soname = NULL;
  96                 exit(EXIT_FAILURE);
  97         }
  98
  99         funcsname = malloc(strlen(config.db_backend)
 100                         + strlen("keydb_")
 101                         + strlen("_funcs")
 102                         + 1);
 103         sprintf(funcsname, "keydb_%s_funcs", config.db_backend);
 104
 105         loaded_backend = dlsym(backend_handle, funcsname);
 106         free(funcsname);
 107
 108         if (loaded_backend == NULL) {
 109                 logthing(LOGTHING_CRITICAL,
 110                                 "Failed to find dbfuncs structure in library "
 111                                 "'%s' : %s", soname, dlerror());
 112                 free(soname);
 113                 soname = NULL;
 114                 exit(EXIT_FAILURE);
 115         }
 116         free(soname);
 117         soname = NULL;
 118
 119         return true;
 120 }
 121
 122 static bool dynamic_starttrans()
 123 {
 124         if (loaded_backend == NULL) {
 125                 load_backend();
 126         }
 127
 128         if (loaded_backend != NULL) {
 129                 if (loaded_backend->starttrans != NULL) {
 130                         return loaded_backend->starttrans();
 131                 }
 132         }
 133
 134         return false;
 135 }
 136
 137 static void dynamic_endtrans()
 138 {
 139         if (loaded_backend == NULL) {
 140                 load_backend();
 141         }
 142
 143         if (loaded_backend != NULL) {
 144                 if (loaded_backend->endtrans != NULL) {
 145                         loaded_backend->endtrans();
 146                 }
 147         }
 148 }
 149
 150 static int dynamic_fetch_key(uint64_t keyid,
 151                 struct openpgp_publickey **publickey, bool intrans)
 152 {
 153         if (loaded_backend == NULL) {
 154                 load_backend();
 155         }
 156
 157         if (loaded_backend != NULL) {
 158                 if (loaded_backend->fetch_key != NULL) {
 159                         return loaded_backend->fetch_key(keyid,publickey,intrans);
 160                 }
 161         }
 162
 163         return -1;
 164 }
 165
 166 static int dynamic_store_key(struct openpgp_publickey *publickey, bool intrans,
 167                 bool update)
 168 {
 169         if (loaded_backend == NULL) {
 170                 load_backend();
 171         }
 172
 173         if (loaded_backend != NULL) {
 174                 if (loaded_backend->store_key != NULL) {
 175                         return loaded_backend->store_key(publickey,intrans,update);
 176                 }
 177         }
 178
 179         return -1;
 180 }
 181
 182 static int dynamic_delete_key(uint64_t keyid, bool intrans)
 183 {
 184         if (loaded_backend == NULL) {
 185                 load_backend();
 186         }
 187
 188         if (loaded_backend != NULL) {
 189                 if (loaded_backend->delete_key != NULL) {
 190                         return loaded_backend->delete_key(keyid, intrans);
 191                 }
 192         }
 193
 194         return -1;
 195 }
 196
 197 static int dynamic_fetch_key_text(const char *search,
 198                 struct openpgp_publickey **publickey)
 199 {
 200         if (loaded_backend == NULL) {
 201                 load_backend();
 202         }
 203
 204         if (loaded_backend != NULL) {
 205                 if (loaded_backend->fetch_key_text != NULL) {
 206                         return loaded_backend->fetch_key_text(search, publickey);
 207                 }
 208         }
 209
 210         return -1;
 211 }
 212
 213 static int dynamic_fetch_key_skshash(const struct skshash *hash,
 214                 struct openpgp_publickey **publickey)
 215 {
 216         if (loaded_backend == NULL) {
 217                 load_backend();
 218         }
 219
 220         if (loaded_backend != NULL) {
 221                 if (loaded_backend->fetch_key_skshash != NULL) {
 222                         return loaded_backend->fetch_key_skshash(hash,
 223                                                                 publickey);
 224                 }
 225         }
 226
 227         return -1;
 228 }
 229
 230 static int dynamic_iterate_keys(void (*iterfunc)(void *ctx,
 231                 struct openpgp_publickey *key), void *ctx)
 232 {
 233         if (loaded_backend == NULL) {
 234                 load_backend();
 235         }
 236
 237         if (loaded_backend != NULL) {
 238                 if (loaded_backend->iterate_keys != NULL) {
 239                         return loaded_backend->iterate_keys(iterfunc, ctx);
 240                 }
 241         }
 242
 243         return -1;
 244 }
 245
 246 /**
 247  *      keyid2uid - Takes a keyid and returns the primary UID for it.
 248  *      @keyid: The keyid to lookup.
 249  */
 250 static char *dynamic_keyid2uid(uint64_t keyid)
 251 {
 252         struct openpgp_publickey *publickey = NULL;
 253         struct openpgp_signedpacket_list *curuid = NULL;
 254         char buf[1024];
 255
 256         if (loaded_backend == NULL) {
 257                 load_backend();
 258         }
 259
 260         if (loaded_backend != NULL) {
 261                 if (loaded_backend->keyid2uid != NULL) {
 262                         return loaded_backend->keyid2uid(keyid);
 263                 }
 264         }
 265
 266         buf[0]=0;
 267         if (dynamic_fetch_key(keyid, &publickey, false) && publickey != NULL) {
 268                 curuid = publickey->uids;
 269                 while (curuid != NULL && buf[0] == 0) {
 270                         if (curuid->packet->tag == OPENPGP_PACKET_UID) {
 271                                 snprintf(buf, 1023, "%.*s",
 272                                                 (int) curuid->packet->length,
 273                                                 curuid->packet->data);
 274                         }
 275                         curuid = curuid -> next;
 276                 }
 277                 free_publickey(publickey);
 278         }
 279
 280         if (buf[0] == 0) {
 281                 return NULL;
 282         } else {
 283                 return strdup(buf);
 284         }
 285 }
 286
 287 /**
 288  *      getkeysigs - Gets a linked list of the signatures on a key.
 289  *      @keyid: The keyid to get the sigs for.
 290  *      @revoked: Is the key revoked?
 291  *
 292  *      This function gets the list of signatures on a key. Used for key
 293  *      indexing and doing stats bits. If revoked is non-NULL then if the key
 294  *      is revoked it's set to true.
 295  */
 296 static struct ll *dynamic_getkeysigs(uint64_t keyid, bool *revoked)
 297 {
 298         struct ll *sigs = NULL;
 299         struct openpgp_signedpacket_list *uids = NULL;
 300         struct openpgp_publickey *publickey = NULL;
 301
 302         if ( loaded_backend == NULL ) {
 303                 load_backend();
 304         }
 305
 306         if (loaded_backend != NULL) {
 307                 if (loaded_backend->getkeysigs != NULL) {
 308                         return loaded_backend->getkeysigs(keyid,revoked);
 309                 }
 310         }
 311
 312         dynamic_fetch_key(keyid, &publickey, false);
 313
 314         if (publickey != NULL) {
 315                 for (uids = publickey->uids; uids != NULL; uids = uids->next) {
 316                         sigs = keysigs(sigs, uids->sigs);
 317                 }
 318                 if (revoked != NULL) {
 319                         *revoked = publickey->revoked;
 320                 }
 321                 free_publickey(publickey);
 322         }
 323
 324         return sigs;
 325 }
 326
 327 /**
 328  *      cached_getkeysigs - Gets the signatures on a key.
 329  *      @keyid: The key we want the signatures for.
 330  *
 331  *      This function gets the signatures on a key. It's the same as the
 332  *      getkeysigs function above except we use the hash module to cache the
 333  *      data so if we need it again it's already loaded.
 334  */
 335 static struct ll *dynamic_cached_getkeysigs(uint64_t keyid)
 336 {
 337         struct stats_key *key = NULL;
 338         struct stats_key *signedkey = NULL;
 339         struct ll        *cursig = NULL;
 340         bool              revoked = false;
 341
 342         if (keyid == 0)  {
 343                 return NULL;
 344         }
 345
 346         if (loaded_backend == NULL) {
 347                 load_backend();
 348         }
 349
 350         if (loaded_backend != NULL) {
 351                 if (loaded_backend->cached_getkeysigs != NULL) {
 352                         return loaded_backend->cached_getkeysigs(keyid);
 353                 }
 354         }
 355
 356         key = createandaddtohash(keyid);
 357
 358         if (key->gotsigs == false) {
 359                 key->sigs = dynamic_getkeysigs(key->keyid, &revoked);
 360                 key->revoked = revoked;
 361                 for (cursig = key->sigs; cursig != NULL;
 362                                 cursig = cursig->next) {
 363                         signedkey = (struct stats_key *) cursig->object;
 364                         signedkey->signs = lladd(signedkey->signs, key);
 365                 }
 366                 key->gotsigs = true;
 367         }
 368
 369         return key->sigs;
 370 }
 371
 372 /**
 373  *      getfullkeyid - Maps a 32bit key id to a 64bit one.
 374  *      @keyid: The 32bit keyid.
 375  *
 376  *      This function maps a 32bit key id to the full 64bit one. It returns the
 377  *      full keyid. If the key isn't found a keyid of 0 is returned.
 378  */
 379 static uint64_t dynamic_getfullkeyid(uint64_t keyid)
 380 {
 381         struct openpgp_publickey *publickey = NULL;
 382
 383         if (loaded_backend == NULL) {
 384                 load_backend();
 385         }
 386
 387         if (loaded_backend != NULL) {
 388                 if (loaded_backend->getfullkeyid != NULL) {
 389                         return loaded_backend->getfullkeyid(keyid);
 390                 }
 391         }
 392
 393         if (keyid < 0x100000000LL) {
 394                 dynamic_fetch_key(keyid, &publickey, false);
 395                 if (publickey != NULL) {
 396                         keyid = get_keyid(publickey);
 397                         free_publickey(publickey);
 398                         publickey = NULL;
 399                 } else {
 400                         keyid = 0;
 401                 }
 402         }
 403
 404         return keyid;
 405 }
 406
 407 /**
 408  *      update_keys - Takes a list of public keys and updates them in the DB.
 409  *      @keys: The keys to update in the DB.
 410  *      @sendsync: Should we send a sync mail to our peers.
 411  *
 412  *      Takes a list of keys and adds them to the database, merging them with
 413  *      the key in the database if it's already present there. The key list is
 414  *      update to contain the minimum set of updates required to get from what
 415  *      we had before to what we have now (ie the set of data that was added to
 416  *      the DB). Returns the number of entirely new keys added.
 417  */
 418 static int dynamic_update_keys(struct openpgp_publickey **keys, bool sendsync)
 419 {
 420         struct openpgp_publickey *curkey = NULL;
 421         struct openpgp_publickey *oldkey = NULL;
 422         struct openpgp_publickey *prev = NULL;
 423         int newkeys = 0;
 424         bool intrans;
 425
 426         if (loaded_backend == NULL) {
 427                 load_backend();
 428         }
 429
 430         if (loaded_backend != NULL) {
 431                 if (loaded_backend->update_keys != NULL) {
 432                         return loaded_backend->update_keys(keys, sendsync);
 433                 }
 434         }
 435
 436         for (curkey = *keys; curkey != NULL; curkey = curkey->next) {
 437                 intrans = dynamic_starttrans();
 438                 logthing(LOGTHING_INFO,
 439                         "Fetching key 0x%" PRIX64 ", result: %d",
 440                         get_keyid(curkey),
 441                         dynamic_fetch_key(get_keyid(curkey), &oldkey, intrans));
 442
 443                 /*
 444                  * If we already have the key stored in the DB then merge it
 445                  * with the new one that's been supplied. Otherwise the key
 446                  * we've just got is the one that goes in the DB and also the
 447                  * one that we send out.
 448                  */
 449                 if (oldkey != NULL) {
 450                         merge_keys(oldkey, curkey);
 451                         if (curkey->sigs == NULL &&
 452                                         curkey->uids == NULL &&
 453                                         curkey->subkeys == NULL) {
 454                                 if (prev == NULL) {
 455                                         *keys = curkey->next;
 456                                 } else {
 457                                         prev->next = curkey->next;
 458                                         curkey->next = NULL;
 459                                         free_publickey(curkey);
 460                                         curkey = prev;
 461                                 }
 462                         } else {
 463                                 prev = curkey;
 464                                 logthing(LOGTHING_INFO,
 465                                         "Merged key; storing updated key.");
 466                                 dynamic_store_key(oldkey, intrans, true);
 467                         }
 468                         free_publickey(oldkey);
 469                         oldkey = NULL;
 470
 471                 } else {
 472                         logthing(LOGTHING_INFO,
 473                                 "Storing completely new key.");
 474                         dynamic_store_key(curkey, intrans, false);
 475                         newkeys++;
 476                 }
 477                 dynamic_endtrans();
 478                 intrans = false;
 479         }
 480
 481         if (sendsync && keys != NULL) {
 482                 sendkeysync(*keys);
 483         }
 484
 485         return newkeys;
 486 }
 487
 488 static void dynamic_initdb(bool readonly)
 489 {
 490         if (loaded_backend == NULL) {
 491                 load_backend();
 492         }
 493
 494         if (loaded_backend != NULL) {
 495                 if (loaded_backend->initdb != NULL) {
 496                         loaded_backend->initdb(readonly);
 497                 }
 498         }
 499 }
 500
 501 static void dynamic_cleanupdb(void)
 502 {
 503         if (loaded_backend != NULL) {
 504                 if (loaded_backend->cleanupdb != NULL) {
 505                         loaded_backend->cleanupdb();
 506                 }
 507         }
 508
 509         close_backend();
 510 }
 511
 512 struct dbfuncs keydb_dynamic_funcs = {
 513         .initdb                 = dynamic_initdb,
 514         .cleanupdb              = dynamic_cleanupdb,
 515         .starttrans             = dynamic_starttrans,
 516         .endtrans               = dynamic_endtrans,
 517         .fetch_key              = dynamic_fetch_key,
 518         .fetch_key_text         = dynamic_fetch_key_text,
 519         .fetch_key_skshash      = dynamic_fetch_key_skshash,
 520         .store_key              = dynamic_store_key,
 521         .update_keys            = dynamic_update_keys,
 522         .delete_key             = dynamic_delete_key,
 523         .getkeysigs             = dynamic_getkeysigs,
 524         .cached_getkeysigs      = dynamic_cached_getkeysigs,
 525         .keyid2uid              = dynamic_keyid2uid,
 526         .getfullkeyid           = dynamic_getfullkeyid,
 527         .iterate_keys           = dynamic_iterate_keys,
 528 };