source3/passdb/secrets.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Copyright (C) Andrew Tridgell 1992-2001
   4    Copyright (C) Andrew Bartlett      2002
   5    Copyright (C) Rafal Szczesniak     2002
   6    Copyright (C) Tim Potter           2001
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 /* the Samba secrets database stores any generated, private information
  23    such as the local SID and machine trust password */
  24
  25 #include "includes.h"
  26 #include "../libcli/auth/libcli_auth.h"
  27 #include "librpc/gen_ndr/ndr_secrets.h"
  28 #include "secrets.h"
  29 #include "dbwrap.h"
  30 #include "../libcli/security/security.h"
  31
  32 #undef DBGC_CLASS
  33 #define DBGC_CLASS DBGC_PASSDB
  34
  35 static struct db_context *db_ctx;
  36
  37 /**
  38  * Use a TDB to store an incrementing random seed.
  39  *
  40  * Initialised to the current pid, the very first time Samba starts,
  41  * and incremented by one each time it is needed.
  42  *
  43  * @note Not called by systems with a working /dev/urandom.
  44  */
  45 static void get_rand_seed(void *userdata, int *new_seed)
  46 {
  47         *new_seed = sys_getpid();
  48         if (db_ctx) {
  49                 dbwrap_trans_change_int32_atomic(db_ctx, "INFO/random_seed",
  50                                                  new_seed, 1);
  51         }
  52 }
  53
  54 /* open up the secrets database */
  55 bool secrets_init(void)
  56 {
  57         char *fname = NULL;
  58         unsigned char dummy;
  59
  60         if (db_ctx != NULL)
  61                 return True;
  62
  63         fname = talloc_asprintf(talloc_tos(), "%s/secrets.tdb",
  64                                 lp_private_dir());
  65         if (fname == NULL) {
  66                 return false;
  67         }
  68
  69         db_ctx = db_open(NULL, fname, 0,
  70                          TDB_DEFAULT, O_RDWR|O_CREAT, 0600);
  71
  72         if (db_ctx == NULL) {
  73                 DEBUG(0,("Failed to open %s\n", fname));
  74                 TALLOC_FREE(fname);
  75                 return False;
  76         }
  77
  78         TALLOC_FREE(fname);
  79
  80         /**
  81          * Set a reseed function for the crypto random generator
  82          *
  83          * This avoids a problem where systems without /dev/urandom
  84          * could send the same challenge to multiple clients
  85          */
  86         set_rand_reseed_callback(get_rand_seed, NULL);
  87
  88         /* Ensure that the reseed is done now, while we are root, etc */
  89         generate_random_buffer(&dummy, sizeof(dummy));
  90
  91         return True;
  92 }
  93
  94 struct db_context *secrets_db_ctx(void)
  95 {
  96         if (!secrets_init()) {
  97                 return NULL;
  98         }
  99
 100         return db_ctx;
 101 }
 102
 103 /*
 104  * close secrets.tdb
 105  */
 106 void secrets_shutdown(void)
 107 {
 108         TALLOC_FREE(db_ctx);
 109 }
 110
 111 /* read a entry from the secrets database - the caller must free the result
 112    if size is non-null then the size of the entry is put in there
 113  */
 114 void *secrets_fetch(const char *key, size_t *size)
 115 {
 116         TDB_DATA dbuf;
 117         void *result;
 118
 119         if (!secrets_init()) {
 120                 return NULL;
 121         }
 122
 123         if (db_ctx->fetch(db_ctx, talloc_tos(), string_tdb_data(key),
 124                           &dbuf) != 0) {
 125                 return NULL;
 126         }
 127
 128         result = memdup(dbuf.dptr, dbuf.dsize);
 129         if (result == NULL) {
 130                 return NULL;
 131         }
 132         TALLOC_FREE(dbuf.dptr);
 133
 134         if (size) {
 135                 *size = dbuf.dsize;
 136         }
 137
 138         return result;
 139 }
 140
 141 /* store a secrets entry
 142  */
 143 bool secrets_store(const char *key, const void *data, size_t size)
 144 {
 145         NTSTATUS status;
 146
 147         if (!secrets_init()) {
 148                 return false;
 149         }
 150
 151         status = dbwrap_trans_store(db_ctx, string_tdb_data(key),
 152                                     make_tdb_data((const uint8 *)data, size),
 153                                     TDB_REPLACE);
 154         return NT_STATUS_IS_OK(status);
 155 }
 156
 157
 158 /* delete a secets database entry
 159  */
 160 bool secrets_delete(const char *key)
 161 {
 162         NTSTATUS status;
 163         if (!secrets_init()) {
 164                 return false;
 165         }
 166
 167         status = dbwrap_trans_delete(db_ctx, string_tdb_data(key));
 168
 169         return NT_STATUS_IS_OK(status);
 170 }
 171
 172 bool secrets_store_local_schannel_key(uint8_t schannel_key[16])
 173 {
 174         return secrets_store(SECRETS_LOCAL_SCHANNEL_KEY, schannel_key, 16);
 175 }
 176
 177 bool secrets_fetch_local_schannel_key(uint8_t schannel_key[16])
 178 {
 179         size_t size = 0;
 180         uint8_t *key;
 181
 182         key = (uint8_t *)secrets_fetch(SECRETS_LOCAL_SCHANNEL_KEY, &size);
 183         if (key == NULL) {
 184                 return false;
 185         }
 186
 187         if (size != 16) {
 188                 SAFE_FREE(key);
 189                 return false;
 190         }
 191
 192         memcpy(schannel_key, key, 16);
 193         SAFE_FREE(key);
 194         return true;
 195 }
 196
 197 /**
 198  * Form a key for fetching a trusted domain password
 199  *
 200  * @param domain trusted domain name
 201  *
 202  * @return stored password's key
 203  **/
 204 static char *trustdom_keystr(const char *domain)
 205 {
 206         char *keystr;
 207
 208         keystr = talloc_asprintf_strupper_m(talloc_tos(), "%s/%s",
 209                                             SECRETS_DOMTRUST_ACCT_PASS,
 210                                             domain);
 211         SMB_ASSERT(keystr != NULL);
 212         return keystr;
 213 }
 214
 215 /************************************************************************
 216  Routine to get account password to trusted domain
 217 ************************************************************************/
 218
 219 bool secrets_fetch_trusted_domain_password(const char *domain, char** pwd,
 220                                            struct dom_sid *sid, time_t *pass_last_set_time)
 221 {
 222         struct TRUSTED_DOM_PASS pass;
 223         enum ndr_err_code ndr_err;
 224
 225         /* unpacking structures */
 226         DATA_BLOB blob;
 227
 228         /* fetching trusted domain password structure */
 229         if (!(blob.data = (uint8_t *)secrets_fetch(trustdom_keystr(domain),
 230                                                    &blob.length))) {
 231                 DEBUG(5, ("secrets_fetch failed!\n"));
 232                 return False;
 233         }
 234
 235         /* unpack trusted domain password */
 236         ndr_err = ndr_pull_struct_blob(&blob, talloc_tos(), &pass,
 237                         (ndr_pull_flags_fn_t)ndr_pull_TRUSTED_DOM_PASS);
 238         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 239                 return false;
 240         }
 241
 242         SAFE_FREE(blob.data);
 243
 244         /* the trust's password */
 245         if (pwd) {
 246                 *pwd = SMB_STRDUP(pass.pass);
 247                 if (!*pwd) {
 248                         return False;
 249                 }
 250         }
 251
 252         /* last change time */
 253         if (pass_last_set_time) *pass_last_set_time = pass.mod_time;
 254
 255         /* domain sid */
 256         if (sid != NULL) sid_copy(sid, &pass.domain_sid);
 257
 258         return True;
 259 }
 260
 261 /**
 262  * Routine to store the password for trusted domain
 263  *
 264  * @param domain remote domain name
 265  * @param pwd plain text password of trust relationship
 266  * @param sid remote domain sid
 267  *
 268  * @return true if succeeded
 269  **/
 270
 271 bool secrets_store_trusted_domain_password(const char* domain, const char* pwd,
 272                                            const struct dom_sid *sid)
 273 {
 274         bool ret;
 275
 276         /* packing structures */
 277         DATA_BLOB blob;
 278         enum ndr_err_code ndr_err;
 279         struct TRUSTED_DOM_PASS pass;
 280         ZERO_STRUCT(pass);
 281
 282         pass.uni_name = domain;
 283         pass.uni_name_len = strlen(domain)+1;
 284
 285         /* last change time */
 286         pass.mod_time = time(NULL);
 287
 288         /* password of the trust */
 289         pass.pass_len = strlen(pwd);
 290         pass.pass = pwd;
 291
 292         /* domain sid */
 293         sid_copy(&pass.domain_sid, sid);
 294
 295         ndr_err = ndr_push_struct_blob(&blob, talloc_tos(), &pass,
 296                         (ndr_push_flags_fn_t)ndr_push_TRUSTED_DOM_PASS);
 297         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 298                 return false;
 299         }
 300
 301         ret = secrets_store(trustdom_keystr(domain), blob.data, blob.length);
 302
 303         data_blob_free(&blob);
 304
 305         return ret;
 306 }
 307
 308 /************************************************************************
 309  Routine to delete the password for trusted domain
 310 ************************************************************************/
 311
 312 bool trusted_domain_password_delete(const char *domain)
 313 {
 314         return secrets_delete(trustdom_keystr(domain));
 315 }
 316
 317 bool secrets_store_ldap_pw(const char* dn, char* pw)
 318 {
 319         char *key = NULL;
 320         bool ret;
 321
 322         if (asprintf(&key, "%s/%s", SECRETS_LDAP_BIND_PW, dn) < 0) {
 323                 DEBUG(0, ("secrets_store_ldap_pw: asprintf failed!\n"));
 324                 return False;
 325         }
 326
 327         ret = secrets_store(key, pw, strlen(pw)+1);
 328
 329         SAFE_FREE(key);
 330         return ret;
 331 }
 332
 333 /*******************************************************************
 334  Find the ldap password.
 335 ******************************************************************/
 336
 337 bool fetch_ldap_pw(char **dn, char** pw)
 338 {
 339         char *key = NULL;
 340         size_t size = 0;
 341
 342         *dn = smb_xstrdup(lp_ldap_admin_dn());
 343
 344         if (asprintf(&key, "%s/%s", SECRETS_LDAP_BIND_PW, *dn) < 0) {
 345                 SAFE_FREE(*dn);
 346                 DEBUG(0, ("fetch_ldap_pw: asprintf failed!\n"));
 347                 return false;
 348         }
 349
 350         *pw=(char *)secrets_fetch(key, &size);
 351         SAFE_FREE(key);
 352
 353         if (!size) {
 354                 /* Upgrade 2.2 style entry */
 355                 char *p;
 356                 char* old_style_key = SMB_STRDUP(*dn);
 357                 char *data;
 358                 fstring old_style_pw;
 359
 360                 if (!old_style_key) {
 361                         DEBUG(0, ("fetch_ldap_pw: strdup failed!\n"));
 362                         return False;
 363                 }
 364
 365                 for (p=old_style_key; *p; p++)
 366                         if (*p == ',') *p = '/';
 367
 368                 data=(char *)secrets_fetch(old_style_key, &size);
 369                 if ((data == NULL) || (size < sizeof(old_style_pw))) {
 370                         DEBUG(0,("fetch_ldap_pw: neither ldap secret retrieved!\n"));
 371                         SAFE_FREE(old_style_key);
 372                         SAFE_FREE(*dn);
 373                         SAFE_FREE(data);
 374                         return False;
 375                 }
 376
 377                 size = MIN(size, sizeof(fstring)-1);
 378                 strncpy(old_style_pw, data, size);
 379                 old_style_pw[size] = 0;
 380
 381                 SAFE_FREE(data);
 382
 383                 if (!secrets_store_ldap_pw(*dn, old_style_pw)) {
 384                         DEBUG(0,("fetch_ldap_pw: ldap secret could not be upgraded!\n"));
 385                         SAFE_FREE(old_style_key);
 386                         SAFE_FREE(*dn);
 387                         return False;
 388                 }
 389                 if (!secrets_delete(old_style_key)) {
 390                         DEBUG(0,("fetch_ldap_pw: old ldap secret could not be deleted!\n"));
 391                 }
 392
 393                 SAFE_FREE(old_style_key);
 394
 395                 *pw = smb_xstrdup(old_style_pw);
 396         }
 397
 398         return True;
 399 }
 400
 401 /**
 402  * Get trusted domains info from secrets.tdb.
 403  **/
 404
 405 struct list_trusted_domains_state {
 406         uint32 num_domains;
 407         struct trustdom_info **domains;
 408 };
 409
 410 static int list_trusted_domain(struct db_record *rec, void *private_data)
 411 {
 412         const size_t prefix_len = strlen(SECRETS_DOMTRUST_ACCT_PASS);
 413         struct TRUSTED_DOM_PASS pass;
 414         enum ndr_err_code ndr_err;
 415         DATA_BLOB blob;
 416         struct trustdom_info *dom_info;
 417
 418         struct list_trusted_domains_state *state =
 419                 (struct list_trusted_domains_state *)private_data;
 420
 421         if ((rec->key.dsize < prefix_len)
 422             || (strncmp((char *)rec->key.dptr, SECRETS_DOMTRUST_ACCT_PASS,
 423                         prefix_len) != 0)) {
 424                 return 0;
 425         }
 426
 427         blob = data_blob_const(rec->value.dptr, rec->value.dsize);
 428
 429         ndr_err = ndr_pull_struct_blob(&blob, talloc_tos(), &pass,
 430                         (ndr_pull_flags_fn_t)ndr_pull_TRUSTED_DOM_PASS);
 431         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 432                 return false;
 433         }
 434
 435         if (pass.domain_sid.num_auths != 4) {
 436                 DEBUG(0, ("SID %s is not a domain sid, has %d "
 437                           "auths instead of 4\n",
 438                           sid_string_dbg(&pass.domain_sid),
 439                           pass.domain_sid.num_auths));
 440                 return 0;
 441         }
 442
 443         if (!(dom_info = TALLOC_P(state->domains, struct trustdom_info))) {
 444                 DEBUG(0, ("talloc failed\n"));
 445                 return 0;
 446         }
 447
 448         dom_info->name = talloc_strdup(dom_info, pass.uni_name);
 449         if (!dom_info->name) {
 450                 TALLOC_FREE(dom_info);
 451                 return 0;
 452         }
 453
 454         sid_copy(&dom_info->sid, &pass.domain_sid);
 455
 456         ADD_TO_ARRAY(state->domains, struct trustdom_info *, dom_info,
 457                      &state->domains, &state->num_domains);
 458
 459         if (state->domains == NULL) {
 460                 state->num_domains = 0;
 461                 return -1;
 462         }
 463         return 0;
 464 }
 465
 466 NTSTATUS secrets_trusted_domains(TALLOC_CTX *mem_ctx, uint32 *num_domains,
 467                                  struct trustdom_info ***domains)
 468 {
 469         struct list_trusted_domains_state state;
 470
 471         secrets_init();
 472
 473         if (db_ctx == NULL) {
 474                 return NT_STATUS_ACCESS_DENIED;
 475         }
 476
 477         state.num_domains = 0;
 478
 479         /*
 480          * Make sure that a talloc context for the trustdom_info structs
 481          * exists
 482          */
 483
 484         if (!(state.domains = TALLOC_ARRAY(
 485                       mem_ctx, struct trustdom_info *, 1))) {
 486                 return NT_STATUS_NO_MEMORY;
 487         }
 488
 489         db_ctx->traverse_read(db_ctx, list_trusted_domain, (void *)&state);
 490
 491         *num_domains = state.num_domains;
 492         *domains = state.domains;
 493         return NT_STATUS_OK;
 494 }
 495
 496 /*******************************************************************************
 497  Store a complete AFS keyfile into secrets.tdb.
 498 *******************************************************************************/
 499
 500 bool secrets_store_afs_keyfile(const char *cell, const struct afs_keyfile *keyfile)
 501 {
 502         fstring key;
 503
 504         if ((cell == NULL) || (keyfile == NULL))
 505                 return False;
 506
 507         if (ntohl(keyfile->nkeys) > SECRETS_AFS_MAXKEYS)
 508                 return False;
 509
 510         slprintf(key, sizeof(key)-1, "%s/%s", SECRETS_AFS_KEYFILE, cell);
 511         return secrets_store(key, keyfile, sizeof(struct afs_keyfile));
 512 }
 513
 514 /*******************************************************************************
 515  Fetch the current (highest) AFS key from secrets.tdb
 516 *******************************************************************************/
 517 bool secrets_fetch_afs_key(const char *cell, struct afs_key *result)
 518 {
 519         fstring key;
 520         struct afs_keyfile *keyfile;
 521         size_t size = 0;
 522         uint32 i;
 523
 524         slprintf(key, sizeof(key)-1, "%s/%s", SECRETS_AFS_KEYFILE, cell);
 525
 526         keyfile = (struct afs_keyfile *)secrets_fetch(key, &size);
 527
 528         if (keyfile == NULL)
 529                 return False;
 530
 531         if (size != sizeof(struct afs_keyfile)) {
 532                 SAFE_FREE(keyfile);
 533                 return False;
 534         }
 535
 536         i = ntohl(keyfile->nkeys);
 537
 538         if (i > SECRETS_AFS_MAXKEYS) {
 539                 SAFE_FREE(keyfile);
 540                 return False;
 541         }
 542
 543         *result = keyfile->entry[i-1];
 544
 545         result->kvno = ntohl(result->kvno);
 546
 547         SAFE_FREE(keyfile);
 548
 549         return True;
 550 }
 551
 552 /******************************************************************************
 553   When kerberos is not available, choose between anonymous or
 554   authenticated connections.
 555
 556   We need to use an authenticated connection if DCs have the
 557   RestrictAnonymous registry entry set > 0, or the "Additional
 558   restrictions for anonymous connections" set in the win2k Local
 559   Security Policy.
 560
 561   Caller to free() result in domain, username, password
 562 *******************************************************************************/
 563 void secrets_fetch_ipc_userpass(char **username, char **domain, char **password)
 564 {
 565         *username = (char *)secrets_fetch(SECRETS_AUTH_USER, NULL);
 566         *domain = (char *)secrets_fetch(SECRETS_AUTH_DOMAIN, NULL);
 567         *password = (char *)secrets_fetch(SECRETS_AUTH_PASSWORD, NULL);
 568
 569         if (*username && **username) {
 570
 571                 if (!*domain || !**domain)
 572                         *domain = smb_xstrdup(lp_workgroup());
 573
 574                 if (!*password || !**password)
 575                         *password = smb_xstrdup("");
 576
 577                 DEBUG(3, ("IPC$ connections done by user %s\\%s\n",
 578                           *domain, *username));
 579
 580         } else {
 581                 DEBUG(3, ("IPC$ connections done anonymously\n"));
 582                 *username = smb_xstrdup("");
 583                 *domain = smb_xstrdup("");
 584                 *password = smb_xstrdup("");
 585         }
 586 }
 587
 588 bool secrets_store_generic(const char *owner, const char *key, const char *secret)
 589 {
 590         char *tdbkey = NULL;
 591         bool ret;
 592
 593         if (asprintf(&tdbkey, "SECRETS/GENERIC/%s/%s", owner, key) < 0) {
 594                 DEBUG(0, ("asprintf failed!\n"));
 595                 return False;
 596         }
 597
 598         ret = secrets_store(tdbkey, secret, strlen(secret)+1);
 599
 600         SAFE_FREE(tdbkey);
 601         return ret;
 602 }
 603
 604 bool secrets_delete_generic(const char *owner, const char *key)
 605 {
 606         char *tdbkey = NULL;
 607         bool ret;
 608
 609         if (asprintf(&tdbkey, "SECRETS/GENERIC/%s/%s", owner, key) < 0) {
 610                 DEBUG(0, ("asprintf failed!\n"));
 611                 return False;
 612         }
 613
 614         ret = secrets_delete(tdbkey);
 615
 616         SAFE_FREE(tdbkey);
 617         return ret;
 618 }
 619
 620 /*******************************************************************
 621  Find the ldap password.
 622 ******************************************************************/
 623
 624 char *secrets_fetch_generic(const char *owner, const char *key)
 625 {
 626         char *secret = NULL;
 627         char *tdbkey = NULL;
 628
 629         if (( ! owner) || ( ! key)) {
 630                 DEBUG(1, ("Invalid Parameters"));
 631                 return NULL;
 632         }
 633
 634         if (asprintf(&tdbkey, "SECRETS/GENERIC/%s/%s", owner, key) < 0) {
 635                 DEBUG(0, ("Out of memory!\n"));
 636                 return NULL;
 637         }
 638
 639         secret = (char *)secrets_fetch(tdbkey, NULL);
 640         SAFE_FREE(tdbkey);
 641
 642         return secret;
 643 }
 644