source4/dsdb/samdb/ldb_modules/password_hash.c

   1 /*
   2    ldb database module
   3
   4    Copyright (C) Simo Sorce  2004
   5    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005
   6    Copyright (C) Andrew Tridgell 2004
   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 2 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, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23 /*
  24  *  Name: ldb
  25  *
  26  *  Component: ldb password_hash module
  27  *
  28  *  Description: correctly update hash values based on changes to sambaPassword and friends
  29  *
  30  *  Author: Andrew Bartlett
  31  */
  32
  33 #include "includes.h"
  34 #include "libcli/ldap/ldap.h"
  35 #include "ldb/include/ldb_errors.h"
  36 #include "ldb/include/ldb_private.h"
  37 #include "librpc/gen_ndr/ndr_misc.h"
  38 #include "librpc/gen_ndr/ndr_samr.h"
  39 #include "system/kerberos.h"
  40 #include "auth/kerberos/kerberos.h"
  41 #include "system/time.h"
  42 #include "dsdb/samdb/samdb.h"
  43 #include "ads.h"
  44 #include "hdb.h"
  45
  46 /* If we have decided there is reason to work on this request, then
  47  * setup all the password hash types correctly.
  48  *
  49  * If the administrator doesn't want the sambaPassword stored (set in the
  50  * domain and per-account policies) then we must strip that out before
  51  * we do the first operation.
  52  *
  53  * Once this is done (which could update anything at all), we
  54  * calculate the password hashes.
  55  *
  56  * This function must not only update the ntPwdHash, lmPwdHash and
  57  * krb5Key fields, it must also atomicly increment the
  58  * msDS-KeyVersionNumber.  We should be in a transaction, so all this
  59  * should be quite safe...
  60  *
  61  * Finally, if the administrator has requested that a password history
  62  * be maintained, then this should also be written out.
  63  *
  64  */
  65
  66
  67 static int password_hash_handle(struct ldb_module *module, struct ldb_request *req,
  68                              const struct ldb_message *msg)
  69 {
  70         int ret, old_ret = -1;
  71         uint_t pwdProperties, pwdHistoryLength;
  72         uint_t userAccountControl;
  73         const char *dnsDomain, *realm;
  74         const char *sambaPassword;
  75         struct samr_Password *sambaLMPwdHistory, *sambaNTPwdHistory;
  76         struct samr_Password *lmPwdHash, *ntPwdHash;
  77         struct samr_Password *lmOldHash = NULL, *ntOldHash = NULL;
  78         struct samr_Password *new_sambaLMPwdHistory, *new_sambaNTPwdHistory;
  79         struct samr_Password local_lmNewHash, local_ntNewHash;
  80         int sambaLMPwdHistory_len, sambaNTPwdHistory_len;
  81         uint_t kvno;
  82         struct dom_sid *domain_sid;
  83         time_t now = time(NULL);
  84         NTTIME now_nt;
  85         int i;
  86         krb5_error_code krb5_ret;
  87
  88         struct smb_krb5_context *smb_krb5_context;
  89
  90         struct ldb_message_element *attribute;
  91         struct ldb_dn *dn = msg->dn;
  92         struct ldb_message *msg2;
  93
  94         struct ldb_request *search_request = NULL;
  95         struct ldb_request *modify_request;
  96         struct ldb_request *modified_orig_request;
  97         struct ldb_result *res, *dom_res, *old_res;
  98
  99         struct ldb_message_element *objectclasses;
 100         struct ldb_val computer_val;
 101         struct ldb_val person_val;
 102         BOOL is_computer;
 103
 104         struct ldb_message *modify_msg;
 105
 106         const char *domain_expression;
 107         const char *old_user_attrs[] = { "lmPwdHash", "ntPwdHash", NULL };
 108         const char *user_attrs[] = { "userAccountControl", "sambaLMPwdHistory",
 109                                      "sambaNTPwdHistory",
 110                                      "ntPwdHash",
 111                                      "objectSid", "msDS-KeyVersionNumber",
 112                                      "objectClass", "userPrincipalName",
 113                                      "samAccountName",
 114                                      NULL };
 115         const char * const domain_attrs[] = { "pwdProperties", "pwdHistoryLength",
 116                                               "dnsDomain", NULL };
 117
 118         TALLOC_CTX *mem_ctx;
 119
 120         /* Do the original action */
 121
 122         /* If no part of this touches the sambaPassword, then we don't
 123          * need to make any changes.  For password changes/set there should
 124          * be a 'delete' or a 'modify' on this attribute. */
 125         if ((attribute = ldb_msg_find_element(msg, "sambaPassword")) == NULL ) {
 126                 return ldb_next_request(module, req);
 127         }
 128
 129         mem_ctx = talloc_new(module);
 130         if (!mem_ctx) {
 131                 return LDB_ERR_OPERATIONS_ERROR;
 132         }
 133
 134         if (req->operation == LDB_REQ_MODIFY) {
 135                 search_request = talloc(mem_ctx, struct ldb_request);
 136                 if (!search_request) {
 137                         talloc_free(mem_ctx);
 138                         return LDB_ERR_OPERATIONS_ERROR;
 139                 }
 140
 141                 /* Look up the old ntPwdHash and lmPwdHash values, so
 142                  * we can later place these into the password
 143                  * history */
 144
 145                 search_request->operation = LDB_REQ_SEARCH;
 146                 search_request->op.search.base = dn;
 147                 search_request->op.search.scope = LDB_SCOPE_BASE;
 148                 search_request->op.search.tree = ldb_parse_tree(module->ldb, NULL);
 149                 search_request->op.search.attrs = old_user_attrs;
 150                 search_request->controls = NULL;
 151
 152                 old_ret = ldb_next_request(module, search_request);
 153         }
 154
 155         /* we can't change things untill we copy it */
 156         msg2 = ldb_msg_copy_shallow(mem_ctx, msg);
 157
 158         /* look again, this time at the copied attribute */
 159         if (!msg2 || (attribute = ldb_msg_find_element(msg2, "sambaPassword")) == NULL ) {
 160                 /* Gah?  where did it go?  Oh well... */
 161                 return LDB_ERR_OPERATIONS_ERROR;
 162         }
 163
 164         /* Wipe out the sambaPassword attribute set, we will handle it in
 165          * the second modify.  We might not want it written to disk */
 166
 167         if (req->operation == LDB_REQ_ADD) {
 168                 if (attribute->num_values != 1) {
 169                         ldb_set_errstring(module,
 170                                           talloc_asprintf(mem_ctx, "sambaPassword_handle: "
 171                                                           "attempted set of multiple sambaPassword attributes on %s rejected",
 172                                                           ldb_dn_linearize(mem_ctx, dn)));
 173                         return LDB_ERR_CONSTRAINT_VIOLAION;
 174                 }
 175
 176                 sambaPassword = (const char *)attribute->values[0].data;
 177                 ldb_msg_remove_attr(msg2, "sambaPassword");
 178         } else if (((attribute->flags & LDB_FLAG_MOD_MASK) == LDB_FLAG_MOD_ADD)
 179                    || ((attribute->flags & LDB_FLAG_MOD_MASK) == LDB_FLAG_MOD_REPLACE)) {
 180                 if (attribute->num_values != 1) {
 181                         return LDB_ERR_CONSTRAINT_VIOLAION;
 182                 }
 183
 184                 sambaPassword = (const char *)attribute->values[0].data;
 185                 ldb_msg_remove_attr(msg2, "sambaPassword");
 186         } else {
 187                 sambaPassword = NULL;
 188         }
 189
 190         modified_orig_request = talloc(mem_ctx, struct ldb_request);
 191         if (!modified_orig_request) {
 192                 talloc_free(mem_ctx);
 193                 return LDB_ERR_OPERATIONS_ERROR;
 194         }
 195
 196         *modified_orig_request = *req;
 197         switch (modified_orig_request->operation) {
 198         case LDB_REQ_ADD:
 199                 modified_orig_request->op.add.message = msg2;
 200                 break;
 201         case LDB_REQ_MODIFY:
 202                 modified_orig_request->op.mod.message = msg2;
 203                 break;
 204         }
 205
 206         /* Send the (modified) request of the original caller down to the database */
 207         ret = ldb_next_request(module, modified_orig_request);
 208         if (ret) {
 209                 return ret;
 210         }
 211
 212         /* While we do the search first (for the old password hashes),
 213          * we don't want to override any error that the modify may
 214          * have returned.  Now check the error */
 215         if (req->operation == LDB_REQ_MODIFY) {
 216                 if (old_ret) {
 217                         talloc_free(mem_ctx);
 218                         return old_ret;
 219                 }
 220
 221                 /* Find out the old passwords details of the user */
 222                 old_res = search_request->op.search.res;
 223
 224                 if (old_res->count != 1) {
 225                         ldb_set_errstring(module,
 226                                           talloc_asprintf(mem_ctx, "password_hash_handle: "
 227                                                           "(pre) search for %s found %d != 1 objects, for entry we just modified",
 228                                                           ldb_dn_linearize(mem_ctx, dn),
 229                                                           old_res->count));
 230                         /* What happend?  The above add/modify worked... */
 231                         talloc_free(mem_ctx);
 232                         return LDB_ERR_NO_SUCH_OBJECT;
 233                 }
 234
 235                 lmOldHash = samdb_result_hash(mem_ctx, old_res->msgs[0],   "lmPwdHash");
 236                 ntOldHash = samdb_result_hash(mem_ctx, old_res->msgs[0],   "ntPwdHash");
 237         }
 238
 239         /* Start finding out details we need for the second modify.
 240          * We do this after the first add/modify because other modules
 241          * will have filled in the templates, and we may have had
 242          * things like the username (affecting the salt) changed along
 243          * with the password. */
 244
 245         /* Now find out what is on the entry after the above add/modify */
 246         search_request = talloc(mem_ctx, struct ldb_request);
 247         if (!search_request) {
 248                 talloc_free(mem_ctx);
 249                 return LDB_ERR_OPERATIONS_ERROR;
 250         }
 251
 252         search_request->operation       = LDB_REQ_SEARCH;
 253         search_request->op.search.base  = dn;
 254         search_request->op.search.scope = LDB_SCOPE_BASE;
 255         search_request->op.search.tree  = ldb_parse_tree(module->ldb, NULL);
 256         search_request->op.search.attrs = user_attrs;
 257         search_request->controls = NULL;
 258
 259         ret = ldb_next_request(module, search_request);
 260         if (ret) {
 261                 talloc_free(mem_ctx);
 262                 return ret;
 263         }
 264
 265         /* Find out the full details of the user */
 266         res = search_request->op.search.res;
 267         if (res->count != 1) {
 268                 ldb_set_errstring(module,
 269                                   talloc_asprintf(mem_ctx, "password_hash_handle: "
 270                                                   "search for %s found %d != 1 objects, for entry we just added/modified",
 271                                                   ldb_dn_linearize(mem_ctx, dn),
 272                                                   res->count));
 273                 /* What happend?  The above add/modify worked... */
 274                 talloc_free(mem_ctx);
 275                 return LDB_ERR_NO_SUCH_OBJECT;
 276         }
 277
 278         userAccountControl = samdb_result_uint(res->msgs[0],   "userAccountControl", 0);
 279         sambaLMPwdHistory_len   = samdb_result_hashes(mem_ctx, res->msgs[0],
 280                                                  "sambaLMPwdHistory", &sambaLMPwdHistory);
 281         sambaNTPwdHistory_len   = samdb_result_hashes(mem_ctx, res->msgs[0],
 282                                                  "sambaNTPwdHistory", &sambaNTPwdHistory);
 283         ntPwdHash          = samdb_result_hash(mem_ctx, res->msgs[0],   "ntPwdHash");
 284         kvno               = samdb_result_uint(res->msgs[0],   "msDS-KeyVersionNumber", 0);
 285
 286         domain_sid         = samdb_result_sid_prefix(mem_ctx, res->msgs[0], "objectSid");
 287
 288
 289         objectclasses = ldb_msg_find_element(res->msgs[0], "objectClass");
 290         person_val = data_blob_string_const("person");
 291
 292         if (!objectclasses || !ldb_msg_find_val(objectclasses, &person_val)) {
 293                 /* Not a 'person', so the rest of this doesn't make
 294                  * sense.  How we got a sambaPassword this far I don't
 295                  * know... */
 296                 ldb_set_errstring(module,
 297                                   talloc_asprintf(mem_ctx, "password_hash_handle: "
 298                                                   "attempted set of sambaPassword on non-'person' object %s rejected",
 299                                                   ldb_dn_linearize(mem_ctx, dn)));
 300                 talloc_free(mem_ctx);
 301                 return LDB_ERR_CONSTRAINT_VIOLAION;
 302         }
 303
 304         computer_val = data_blob_string_const("computer");
 305
 306         if (ldb_msg_find_val(objectclasses, &computer_val)) {
 307                 is_computer = True;
 308         } else {
 309                 is_computer = False;
 310         }
 311
 312         domain_expression  = talloc_asprintf(mem_ctx, "(&(objectSid=%s)(objectClass=domain))",
 313                                              ldap_encode_ndr_dom_sid(mem_ctx, domain_sid));
 314
 315         /* Find the user's domain, then find out the domain password
 316          * properties */
 317         ret = ldb_search(module->ldb, NULL, LDB_SCOPE_SUBTREE, domain_expression,
 318                          domain_attrs, &dom_res);
 319         if (ret) {
 320                 talloc_free(mem_ctx);
 321                 return ret;
 322         }
 323
 324         if (dom_res->count != 1) {
 325                 /* What happend?  The user we are modifying must be odd... */
 326                 ldb_set_errstring(module,
 327                                   talloc_asprintf(mem_ctx, "password_hash_handle: "
 328                                                   "search for domain %s found %d != 1 objects",
 329                                                   dom_sid_string(mem_ctx, domain_sid),
 330                                                   dom_res->count));
 331                 talloc_free(mem_ctx);
 332                 return LDB_ERR_NO_SUCH_OBJECT;
 333         }
 334
 335         pwdProperties    = samdb_result_uint(dom_res->msgs[0],   "pwdProperties", 0);
 336         pwdHistoryLength = samdb_result_uint(dom_res->msgs[0],   "pwdHistoryLength", 0);
 337         dnsDomain        = ldb_msg_find_string(dom_res->msgs[0], "dnsDomain", NULL);
 338         realm            = strupper_talloc(mem_ctx, dnsDomain);
 339
 340         /* Some operations below require kerberos contexts */
 341         if (smb_krb5_init_context(mem_ctx, &smb_krb5_context) != 0) {
 342                 talloc_free(mem_ctx);
 343                 return LDB_ERR_OPERATIONS_ERROR;
 344         }
 345
 346         /* Prepare the modifications to set all the hash/key types */
 347         modify_msg = ldb_msg_new(req);
 348         modify_msg->dn = talloc_reference(modify_msg, dn);
 349
 350 #define CHECK_RET(x) \
 351         do {                                    \
 352                 int check_ret = x;              \
 353                 if (check_ret != LDB_SUCCESS) { \
 354                         talloc_free(mem_ctx);   \
 355                         return check_ret;       \
 356                 }                               \
 357         } while(0)
 358
 359         /* Setup krb5Key (we want to either delete an existing value,
 360          * or replace with a new one).  Both the unicode and NT hash
 361          * only branches append keys to this multivalued entry. */
 362         CHECK_RET(ldb_msg_add_empty(modify_msg, "krb5Key", LDB_FLAG_MOD_REPLACE));
 363         /* Yay, we can compute new password hashes from the unicode
 364          * password */
 365         if (sambaPassword) {
 366                 Principal *salt_principal;
 367                 const char *user_principal_name = ldb_msg_find_string(res->msgs[0], "userPrincipalName", NULL);
 368
 369                 Key *keys;
 370                 size_t num_keys;
 371
 372                 /* compute the new nt and lm hashes */
 373                 if (E_deshash(sambaPassword, local_lmNewHash.hash)) {
 374                         lmPwdHash = &local_lmNewHash;
 375                 } else {
 376                         lmPwdHash = NULL;
 377                 }
 378                 E_md4hash(sambaPassword, local_ntNewHash.hash);
 379                 ntPwdHash = &local_ntNewHash;
 380                 CHECK_RET(ldb_msg_add_empty(modify_msg, "ntPwdHash",
 381                                             LDB_FLAG_MOD_REPLACE));
 382                 CHECK_RET(samdb_msg_add_hash(module->ldb, req,
 383                                              modify_msg, "ntPwdHash",
 384                                              ntPwdHash));
 385                 CHECK_RET(ldb_msg_add_empty(modify_msg, "lmPwdHash",
 386                                             LDB_FLAG_MOD_REPLACE));
 387                 if (lmPwdHash) {
 388                         CHECK_RET(samdb_msg_add_hash(module->ldb, req,
 389                                                      modify_msg, "lmPwdHash",
 390                                                      lmPwdHash));
 391                 }
 392
 393                 /* Many, many thanks to lukeh@padl.com for this
 394                  * algorithm, described in his Nov 10 2004 mail to
 395                  * samba-technical@samba.org */
 396
 397                 if (is_computer) {
 398                         /* Determine a salting principal */
 399                         char *samAccountName = talloc_strdup(mem_ctx, ldb_msg_find_string(res->msgs[0], "samAccountName", NULL));
 400                         char *saltbody;
 401                         if (!samAccountName) {
 402                                 ldb_set_errstring(module,
 403                                                   talloc_asprintf(mem_ctx, "password_hash_handle: "
 404                                                                   "generation of new kerberos keys failed: %s is a computer without a samAccountName",
 405                                                                   ldb_dn_linearize(mem_ctx, dn)));
 406                                 talloc_free(mem_ctx);
 407                                 return LDB_ERR_OPERATIONS_ERROR;
 408                         }
 409                         if (samAccountName[strlen(samAccountName)-1] == '$') {
 410                                 samAccountName[strlen(samAccountName)-1] = '\0';
 411                         }
 412                         saltbody = talloc_asprintf(mem_ctx, "%s.%s", samAccountName, dnsDomain);
 413
 414                         krb5_ret = krb5_make_principal(smb_krb5_context->krb5_context, &salt_principal, realm, "host", saltbody, NULL);
 415                 } else if (user_principal_name) {
 416                         char *p;
 417                         user_principal_name = talloc_strdup(mem_ctx, user_principal_name);
 418                         if (!user_principal_name) {
 419                                 talloc_free(mem_ctx);
 420                                 return LDB_ERR_OPERATIONS_ERROR;
 421                         } else {
 422                                 p = strchr(user_principal_name, '@');
 423                                 if (p) {
 424                                         p[0] = '\0';
 425                                 }
 426                                 krb5_ret = krb5_make_principal(smb_krb5_context->krb5_context, &salt_principal, realm, user_principal_name, NULL);
 427                         }
 428                 } else {
 429                         const char *samAccountName = ldb_msg_find_string(res->msgs[0], "samAccountName", NULL);
 430                         if (!samAccountName) {
 431                                 ldb_set_errstring(module,
 432                                                   talloc_asprintf(mem_ctx, "password_hash_handle: "
 433                                                                   "generation of new kerberos keys failed: %s has no samAccountName",
 434                                                                   ldb_dn_linearize(mem_ctx, dn)));
 435                                 talloc_free(mem_ctx);
 436                                 return LDB_ERR_OPERATIONS_ERROR;
 437                         }
 438                         krb5_ret = krb5_make_principal(smb_krb5_context->krb5_context, &salt_principal, realm, samAccountName, NULL);
 439                 }
 440
 441
 442                 if (krb5_ret) {
 443                         ldb_set_errstring(module,
 444                                           talloc_asprintf(mem_ctx, "password_hash_handle: "
 445                                                           "generation of a saltking principal failed: %s",
 446                                                           smb_get_krb5_error_message(smb_krb5_context->krb5_context,
 447                                                                                      krb5_ret, mem_ctx)));
 448                         talloc_free(mem_ctx);
 449                         return LDB_ERR_OPERATIONS_ERROR;
 450                 }
 451
 452                 /* TODO: We may wish to control the encryption types chosen in future */
 453                 krb5_ret = hdb_generate_key_set_password(smb_krb5_context->krb5_context,
 454                                                     salt_principal, sambaPassword, &keys, &num_keys);
 455                 krb5_free_principal(smb_krb5_context->krb5_context, salt_principal);
 456
 457                 if (krb5_ret) {
 458                         ldb_set_errstring(module,
 459                                           talloc_asprintf(mem_ctx, "password_hash_handle: "
 460                                                           "generation of new kerberos keys failed: %s",
 461                                                           smb_get_krb5_error_message(smb_krb5_context->krb5_context,
 462                                                                                      krb5_ret, mem_ctx)));
 463                         talloc_free(mem_ctx);
 464                         return LDB_ERR_OPERATIONS_ERROR;
 465                 }
 466
 467                 /* Walking
 468                  */
 469                 for (i=0; i < num_keys; i++) {
 470                         unsigned char *buf;
 471                         size_t buf_size;
 472                         size_t len;
 473                         struct ldb_val val;
 474
 475                         if (keys[i].key.keytype == ENCTYPE_ARCFOUR_HMAC) {
 476                                 /* We might end up doing this below:
 477                                  * This ensures we get the unicode
 478                                  * conversion right.  This should also
 479                                  * be fixed in the Heimdal libs */
 480                                 continue;
 481                         }
 482                         ASN1_MALLOC_ENCODE(Key, buf, buf_size, &keys[i], &len, krb5_ret);
 483
 484                         val.data = talloc_memdup(req, buf, len);
 485                         val.length = len;
 486                         free(buf);
 487                         if (!val.data || krb5_ret) {
 488                                 hdb_free_keys (smb_krb5_context->krb5_context, num_keys, keys);
 489                                 talloc_free(mem_ctx);
 490                                 return LDB_ERR_OPERATIONS_ERROR;
 491                         }
 492                         ret = ldb_msg_add_value(modify_msg, "krb5Key", &val);
 493                         if (ret != LDB_SUCCESS) {
 494                                 hdb_free_keys (smb_krb5_context->krb5_context, num_keys, keys);
 495                                 talloc_free(mem_ctx);
 496                                 return ret;
 497                         }
 498                 }
 499
 500                 hdb_free_keys (smb_krb5_context->krb5_context, num_keys, keys);
 501         }
 502
 503         /* Possibly kill off the cleartext or store it */
 504         CHECK_RET(ldb_msg_add_empty(modify_msg, "sambaPassword", LDB_FLAG_MOD_REPLACE));
 505
 506         if (sambaPassword && (pwdProperties & DOMAIN_PASSWORD_STORE_CLEARTEXT) &&
 507             (userAccountControl & UF_ENCRYPTED_TEXT_PASSWORD_ALLOWED)) {
 508                 CHECK_RET(ldb_msg_add_string(modify_msg, "sambaPassword", sambaPassword));
 509         }
 510
 511         /* Even if we didn't get a sambaPassword, we can still setup
 512          * krb5Key from the NT hash.
 513          *
 514          * This is an append, so it works with the 'continue' in the
 515          * unicode loop above, to use Samba's NT hash function, which
 516          * is more correct than Heimdal's
 517          */
 518         if (ntPwdHash) {
 519                 unsigned char *buf;
 520                 size_t buf_size;
 521                 size_t len;
 522                 struct ldb_val val;
 523                 Key key;
 524
 525                 key.mkvno = 0;
 526                 key.salt = NULL; /* No salt for this enc type */
 527
 528                 krb5_ret = krb5_keyblock_init(smb_krb5_context->krb5_context,
 529                                          ENCTYPE_ARCFOUR_HMAC,
 530                                          ntPwdHash->hash, sizeof(ntPwdHash->hash),
 531                                          &key.key);
 532                 if (krb5_ret) {
 533                         return LDB_ERR_OPERATIONS_ERROR;
 534                 }
 535                 ASN1_MALLOC_ENCODE(Key, buf, buf_size, &key, &len, krb5_ret);
 536                 krb5_free_keyblock_contents(smb_krb5_context->krb5_context,
 537                                             &key.key);
 538
 539                 val.data = talloc_memdup(req, buf, len);
 540                 val.length = len;
 541                 free(buf);
 542                 if (!val.data || ret) {
 543                         return LDB_ERR_OPERATIONS_ERROR;
 544                 }
 545                 CHECK_RET(ldb_msg_add_value(modify_msg, "krb5Key", &val));
 546         }
 547
 548         /* If the original caller did anything with pwdLastSet then skip this.  It could be an incoming samsync */
 549         if ((attribute = ldb_msg_find_element(msg, "pwdLastSet")) == NULL ) {
 550                 /* Update the password last set time */
 551                 unix_to_nt_time(&now_nt, now);
 552                 CHECK_RET(ldb_msg_add_empty(modify_msg, "pwdLastSet", LDB_FLAG_MOD_REPLACE));
 553                 CHECK_RET(samdb_msg_add_uint64(module->ldb, mem_ctx, modify_msg, "pwdLastSet", now_nt));
 554         }
 555
 556         /* If the original caller did anything with "msDS-KeyVersionNumber" then skip this.  It could be an incoming samsync */
 557         if ((attribute = ldb_msg_find_element(msg, "msDS-KeyVersionNumber")) == NULL ) {
 558                 if (kvno == 0) {
 559                         CHECK_RET(ldb_msg_add_empty(modify_msg, "msDS-KeyVersionNumber",
 560                                                     LDB_FLAG_MOD_REPLACE));
 561                         CHECK_RET(samdb_msg_add_uint(module->ldb, mem_ctx, modify_msg, "msDS-KeyVersionNumber", kvno + 1));
 562                 } else {
 563                         /* While we should be in a transaction, go one extra
 564                          * step in the dance for an 'atomic' increment.  This
 565                          * may be of value against remote LDAP servers.  (Note
 566                          * however that Mulitmaster replication stil offers no
 567                          * such guarantee) */
 568
 569                         struct ldb_val old_kvno, new_kvno;
 570                         old_kvno.data = (uint8_t *)talloc_asprintf(mem_ctx, "%u", kvno);
 571                         if (!old_kvno.data) {
 572                                 return -1;
 573                         }
 574                         old_kvno.length = strlen((char *)old_kvno.data);
 575
 576                         new_kvno.data = (uint8_t *)talloc_asprintf(mem_ctx, "%u", kvno + 1);
 577                         if (!new_kvno.data) {
 578                                 return -1;
 579                         }
 580                         new_kvno.length = strlen((char *)new_kvno.data);
 581
 582                         CHECK_RET(ldb_msg_add_empty(modify_msg, "msDS-KeyVersionNumber",
 583                                                     LDB_FLAG_MOD_DELETE));
 584                         CHECK_RET(ldb_msg_add_empty(modify_msg, "msDS-KeyVersionNumber",
 585                                                     LDB_FLAG_MOD_ADD));
 586                         modify_msg->elements[modify_msg->num_elements - 2].num_values = 1;
 587                         modify_msg->elements[modify_msg->num_elements - 2].values = &old_kvno;
 588                         modify_msg->elements[modify_msg->num_elements - 1].num_values = 1;
 589                         modify_msg->elements[modify_msg->num_elements - 1].values = &new_kvno;
 590                 }
 591         }
 592
 593         CHECK_RET(ldb_msg_add_empty(modify_msg, "sambaLMPwdHistory",
 594                                     LDB_FLAG_MOD_REPLACE));
 595         CHECK_RET(ldb_msg_add_empty(modify_msg, "sambaNTPwdHistory",
 596                                     LDB_FLAG_MOD_REPLACE));
 597
 598         /* If we have something to put into the history, or an old
 599          * history element to expire, update the history */
 600         if (pwdHistoryLength > 0 &&
 601             ((sambaNTPwdHistory_len > 0) || (sambaLMPwdHistory_len > 0)
 602              || lmOldHash || ntOldHash)) {
 603                 /* store the password history */
 604                 new_sambaLMPwdHistory = talloc_array(mem_ctx, struct samr_Password,
 605                                                 pwdHistoryLength);
 606                 if (!new_sambaLMPwdHistory) {
 607                         return LDB_ERR_OPERATIONS_ERROR;
 608                 }
 609                 new_sambaNTPwdHistory = talloc_array(mem_ctx, struct samr_Password,
 610                                                 pwdHistoryLength);
 611                 if (!new_sambaNTPwdHistory) {
 612                         return LDB_ERR_OPERATIONS_ERROR;
 613                 }
 614                 for (i=0;i<MIN(pwdHistoryLength-1, sambaLMPwdHistory_len);i++) {
 615                         new_sambaLMPwdHistory[i+1] = sambaLMPwdHistory[i];
 616                 }
 617                 for (i=0;i<MIN(pwdHistoryLength-1, sambaNTPwdHistory_len);i++) {
 618                         new_sambaNTPwdHistory[i+1] = sambaNTPwdHistory[i];
 619                 }
 620
 621                 /* Don't store 'long' passwords in the LM history,
 622                    but make sure to 'expire' one password off the other end */
 623                 if (lmOldHash) {
 624                         new_sambaLMPwdHistory[0] = *lmOldHash;
 625                 } else {
 626                         ZERO_STRUCT(new_sambaLMPwdHistory[0]);
 627                 }
 628                 sambaLMPwdHistory_len = MIN(sambaLMPwdHistory_len + 1, pwdHistoryLength);
 629
 630                 /* Likewise, we might not have a new NT password (lm
 631                  * only password change function) */
 632                 if (ntOldHash) {
 633                         new_sambaNTPwdHistory[0] = *ntOldHash;
 634                 } else {
 635                         ZERO_STRUCT(new_sambaNTPwdHistory[0]);
 636                 }
 637                 sambaNTPwdHistory_len = MIN(sambaNTPwdHistory_len + 1, pwdHistoryLength);
 638
 639                 CHECK_RET(samdb_msg_add_hashes(module->ldb, mem_ctx, modify_msg,
 640                                                "sambaLMPwdHistory",
 641                                                new_sambaLMPwdHistory,
 642                                                sambaLMPwdHistory_len));
 643
 644                 CHECK_RET(samdb_msg_add_hashes(module->ldb, mem_ctx, modify_msg,
 645                                                "sambaNTPwdHistory",
 646                                                new_sambaNTPwdHistory,
 647                                                sambaNTPwdHistory_len));
 648         }
 649
 650         /* Too much code above, we should check we got it close to reasonable */
 651         CHECK_RET(ldb_msg_sanity_check(modify_msg));
 652
 653         modify_request = talloc(mem_ctx, struct ldb_request);
 654         if (!modify_request) {
 655                 talloc_free(mem_ctx);
 656                 return LDB_ERR_OPERATIONS_ERROR;
 657         }
 658
 659         modify_request->operation = LDB_REQ_MODIFY;
 660         modify_request->op.mod.message = modify_msg;
 661         modify_request->controls = NULL;
 662
 663         ret = ldb_next_request(module, modify_request);
 664
 665         talloc_free(mem_ctx);
 666         return ret;
 667 }
 668
 669 /* add_record: do things with the sambaPassword attribute */
 670 static int password_hash_add(struct ldb_module *module, struct ldb_request *req)
 671 {
 672         const struct ldb_message *msg = req->op.add.message;
 673
 674         ldb_debug(module->ldb, LDB_DEBUG_TRACE, "password_hash_add_record\n");
 675
 676         if (ldb_dn_is_special(msg->dn)) { /* do not manipulate our control entries */
 677                 return ldb_next_request(module, req);
 678         }
 679
 680         return password_hash_handle(module, req, msg);
 681 }
 682
 683 /* modify_record: do things with the sambaPassword attribute */
 684 static int password_hash_modify(struct ldb_module *module, struct ldb_request *req)
 685 {
 686         const struct ldb_message *msg = req->op.mod.message;
 687
 688         ldb_debug(module->ldb, LDB_DEBUG_TRACE, "password_hash_modify_record\n");
 689
 690         if (ldb_dn_is_special(msg->dn)) { /* do not manipulate our control entries */
 691                 return ldb_next_request(module, req);
 692         }
 693
 694         return password_hash_handle(module, req, msg);
 695 }
 696
 697 static int password_hash_request(struct ldb_module *module, struct ldb_request *req)
 698 {
 699         switch (req->operation) {
 700
 701         case LDB_REQ_ADD:
 702                 return password_hash_add(module, req);
 703
 704         case LDB_REQ_MODIFY:
 705                 return password_hash_modify(module, req);
 706
 707         default:
 708                 return ldb_next_request(module, req);
 709
 710         }
 711 }
 712
 713 static const struct ldb_module_ops password_hash_ops = {
 714         .name          = "password_hash",
 715         .request       = password_hash_request
 716 };
 717
 718
 719 /* the init function */
 720 struct ldb_module *password_hash_module_init(struct ldb_context *ldb, const char *options[])
 721 {
 722         struct ldb_module *ctx;
 723
 724         ctx = talloc(ldb, struct ldb_module);
 725         if (!ctx)
 726                 return NULL;
 727
 728         ctx->private_data = NULL;
 729         ctx->ldb = ldb;
 730         ctx->prev = ctx->next = NULL;
 731         ctx->ops = &password_hash_ops;
 732
 733         return ctx;
 734 }