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 = NULL;
  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_VIOLATION;
 174                 }
 175
 176                 if (attribute->num_values == 1) {
 177                         sambaPassword = (const char *)attribute->values[0].data;
 178                         ldb_msg_remove_attr(msg2, "sambaPassword");
 179                 }
 180         } else if (((attribute->flags & LDB_FLAG_MOD_MASK) == LDB_FLAG_MOD_ADD)
 181                    || ((attribute->flags & LDB_FLAG_MOD_MASK) == LDB_FLAG_MOD_REPLACE)) {
 182                 if (attribute->num_values > 1) {
 183                         ldb_set_errstring(module,
 184                                           talloc_asprintf(mem_ctx, "sambaPassword_handle: "
 185                                                           "attempted set of multiple sambaPassword attributes on %s rejected",
 186                                                           ldb_dn_linearize(mem_ctx, dn)));
 187                         return LDB_ERR_CONSTRAINT_VIOLATION;
 188                 }
 189
 190                 if (attribute->num_values == 1) {
 191                         sambaPassword = (const char *)attribute->values[0].data;
 192                         ldb_msg_remove_attr(msg2, "sambaPassword");
 193                 }
 194         }
 195
 196         modified_orig_request = talloc(mem_ctx, struct ldb_request);
 197         if (!modified_orig_request) {
 198                 talloc_free(mem_ctx);
 199                 return LDB_ERR_OPERATIONS_ERROR;
 200         }
 201
 202         *modified_orig_request = *req;
 203         switch (modified_orig_request->operation) {
 204         case LDB_REQ_ADD:
 205                 modified_orig_request->op.add.message = msg2;
 206                 break;
 207         case LDB_REQ_MODIFY:
 208                 modified_orig_request->op.mod.message = msg2;
 209                 break;
 210         }
 211
 212         /* Send the (modified) request of the original caller down to the database */
 213         ret = ldb_next_request(module, modified_orig_request);
 214         if (ret) {
 215                 return ret;
 216         }
 217
 218         /* While we do the search first (for the old password hashes),
 219          * we don't want to override any error that the modify may
 220          * have returned.  Now check the error */
 221         if (req->operation == LDB_REQ_MODIFY) {
 222                 if (old_ret) {
 223                         talloc_free(mem_ctx);
 224                         return old_ret;
 225                 }
 226
 227                 /* Find out the old passwords details of the user */
 228                 old_res = search_request->op.search.res;
 229
 230                 if (old_res->count != 1) {
 231                         ldb_set_errstring(module,
 232                                           talloc_asprintf(mem_ctx, "password_hash_handle: "
 233                                                           "(pre) search for %s found %d != 1 objects, for entry we just modified",
 234                                                           ldb_dn_linearize(mem_ctx, dn),
 235                                                           old_res->count));
 236                         /* What happend?  The above add/modify worked... */
 237                         talloc_free(mem_ctx);
 238                         return LDB_ERR_NO_SUCH_OBJECT;
 239                 }
 240
 241                 lmOldHash = samdb_result_hash(mem_ctx, old_res->msgs[0],   "lmPwdHash");
 242                 ntOldHash = samdb_result_hash(mem_ctx, old_res->msgs[0],   "ntPwdHash");
 243         }
 244
 245         /* Start finding out details we need for the second modify.
 246          * We do this after the first add/modify because other modules
 247          * will have filled in the templates, and we may have had
 248          * things like the username (affecting the salt) changed along
 249          * with the password. */
 250
 251         /* Now find out what is on the entry after the above add/modify */
 252         search_request = talloc(mem_ctx, struct ldb_request);
 253         if (!search_request) {
 254                 talloc_free(mem_ctx);
 255                 return LDB_ERR_OPERATIONS_ERROR;
 256         }
 257
 258         search_request->operation       = LDB_REQ_SEARCH;
 259         search_request->op.search.base  = dn;
 260         search_request->op.search.scope = LDB_SCOPE_BASE;
 261         search_request->op.search.tree  = ldb_parse_tree(module->ldb, NULL);
 262         search_request->op.search.attrs = user_attrs;
 263         search_request->controls = NULL;
 264
 265         ret = ldb_next_request(module, search_request);
 266         if (ret) {
 267                 talloc_free(mem_ctx);
 268                 return ret;
 269         }
 270
 271         /* Find out the full details of the user */
 272         res = search_request->op.search.res;
 273         if (res->count != 1) {
 274                 ldb_set_errstring(module,
 275                                   talloc_asprintf(mem_ctx, "password_hash_handle: "
 276                                                   "search for %s found %d != 1 objects, for entry we just added/modified",
 277                                                   ldb_dn_linearize(mem_ctx, dn),
 278                                                   res->count));
 279                 /* What happend?  The above add/modify worked... */
 280                 talloc_free(mem_ctx);
 281                 return LDB_ERR_NO_SUCH_OBJECT;
 282         }
 283
 284         userAccountControl = samdb_result_uint(res->msgs[0],   "userAccountControl", 0);
 285         sambaLMPwdHistory_len   = samdb_result_hashes(mem_ctx, res->msgs[0],
 286                                                  "sambaLMPwdHistory", &sambaLMPwdHistory);
 287         sambaNTPwdHistory_len   = samdb_result_hashes(mem_ctx, res->msgs[0],
 288                                                  "sambaNTPwdHistory", &sambaNTPwdHistory);
 289         ntPwdHash          = samdb_result_hash(mem_ctx, res->msgs[0],   "ntPwdHash");
 290         kvno               = samdb_result_uint(res->msgs[0],   "msDS-KeyVersionNumber", 0);
 291
 292         domain_sid         = samdb_result_sid_prefix(mem_ctx, res->msgs[0], "objectSid");
 293
 294
 295         objectclasses = ldb_msg_find_element(res->msgs[0], "objectClass");
 296         person_val = data_blob_string_const("person");
 297
 298         if (!objectclasses || !ldb_msg_find_val(objectclasses, &person_val)) {
 299                 /* Not a 'person', so the rest of this doesn't make
 300                  * sense.  How we got a sambaPassword this far I don't
 301                  * know... */
 302                 ldb_set_errstring(module,
 303                                   talloc_asprintf(mem_ctx, "password_hash_handle: "
 304                                                   "attempted set of sambaPassword on non-'person' object %s rejected",
 305                                                   ldb_dn_linearize(mem_ctx, dn)));
 306                 talloc_free(mem_ctx);
 307                 return LDB_ERR_CONSTRAINT_VIOLATION;
 308         }
 309
 310         computer_val = data_blob_string_const("computer");
 311
 312         if (ldb_msg_find_val(objectclasses, &computer_val)) {
 313                 is_computer = True;
 314         } else {
 315                 is_computer = False;
 316         }
 317
 318         domain_expression  = talloc_asprintf(mem_ctx, "(&(objectSid=%s)(objectClass=domain))",
 319                                              ldap_encode_ndr_dom_sid(mem_ctx, domain_sid));
 320
 321         /* Find the user's domain, then find out the domain password
 322          * properties */
 323         ret = ldb_search(module->ldb, NULL, LDB_SCOPE_SUBTREE, domain_expression,
 324                          domain_attrs, &dom_res);
 325         if (ret) {
 326                 talloc_free(mem_ctx);
 327                 return ret;
 328         }
 329
 330         if (dom_res->count != 1) {
 331                 /* What happend?  The user we are modifying must be odd... */
 332                 ldb_set_errstring(module,
 333                                   talloc_asprintf(mem_ctx, "password_hash_handle: "
 334                                                   "search for domain %s found %d != 1 objects",
 335                                                   dom_sid_string(mem_ctx, domain_sid),
 336                                                   dom_res->count));
 337                 talloc_free(mem_ctx);
 338                 return LDB_ERR_NO_SUCH_OBJECT;
 339         }
 340
 341         pwdProperties    = samdb_result_uint(dom_res->msgs[0],   "pwdProperties", 0);
 342         pwdHistoryLength = samdb_result_uint(dom_res->msgs[0],   "pwdHistoryLength", 0);
 343         dnsDomain        = ldb_msg_find_string(dom_res->msgs[0], "dnsDomain", NULL);
 344         realm            = strupper_talloc(mem_ctx, dnsDomain);
 345
 346         /* Some operations below require kerberos contexts */
 347         if (smb_krb5_init_context(mem_ctx, &smb_krb5_context) != 0) {
 348                 talloc_free(mem_ctx);
 349                 return LDB_ERR_OPERATIONS_ERROR;
 350         }
 351
 352         /* Prepare the modifications to set all the hash/key types */
 353         modify_msg = ldb_msg_new(req);
 354         modify_msg->dn = talloc_reference(modify_msg, dn);
 355
 356 #define CHECK_RET(x) \
 357         do {                                    \
 358                 int check_ret = x;              \
 359                 if (check_ret != LDB_SUCCESS) { \
 360                         talloc_free(mem_ctx);   \
 361                         return check_ret;       \
 362                 }                               \
 363         } while(0)
 364
 365         /* Setup krb5Key (we want to either delete an existing value,
 366          * or replace with a new one).  Both the unicode and NT hash
 367          * only branches append keys to this multivalued entry. */
 368         CHECK_RET(ldb_msg_add_empty(modify_msg, "krb5Key", LDB_FLAG_MOD_REPLACE));
 369         /* Yay, we can compute new password hashes from the unicode
 370          * password */
 371         if (sambaPassword) {
 372                 Principal *salt_principal;
 373                 const char *user_principal_name = ldb_msg_find_string(res->msgs[0], "userPrincipalName", NULL);
 374
 375                 Key *keys;
 376                 size_t num_keys;
 377
 378                 /* compute the new nt and lm hashes */
 379                 if (E_deshash(sambaPassword, local_lmNewHash.hash)) {
 380                         lmPwdHash = &local_lmNewHash;
 381                 } else {
 382                         lmPwdHash = NULL;
 383                 }
 384                 E_md4hash(sambaPassword, local_ntNewHash.hash);
 385                 ntPwdHash = &local_ntNewHash;
 386                 CHECK_RET(ldb_msg_add_empty(modify_msg, "ntPwdHash",
 387                                             LDB_FLAG_MOD_REPLACE));
 388                 CHECK_RET(samdb_msg_add_hash(module->ldb, req,
 389                                              modify_msg, "ntPwdHash",
 390                                              ntPwdHash));
 391                 CHECK_RET(ldb_msg_add_empty(modify_msg, "lmPwdHash",
 392                                             LDB_FLAG_MOD_REPLACE));
 393                 if (lmPwdHash) {
 394                         CHECK_RET(samdb_msg_add_hash(module->ldb, req,
 395                                                      modify_msg, "lmPwdHash",
 396                                                      lmPwdHash));
 397                 }
 398
 399                 /* Many, many thanks to lukeh@padl.com for this
 400                  * algorithm, described in his Nov 10 2004 mail to
 401                  * samba-technical@samba.org */
 402
 403                 if (is_computer) {
 404                         /* Determine a salting principal */
 405                         char *samAccountName = talloc_strdup(mem_ctx, ldb_msg_find_string(res->msgs[0], "samAccountName", NULL));
 406                         char *saltbody;
 407                         if (!samAccountName) {
 408                                 ldb_set_errstring(module,
 409                                                   talloc_asprintf(mem_ctx, "password_hash_handle: "
 410                                                                   "generation of new kerberos keys failed: %s is a computer without a samAccountName",
 411                                                                   ldb_dn_linearize(mem_ctx, dn)));
 412                                 talloc_free(mem_ctx);
 413                                 return LDB_ERR_OPERATIONS_ERROR;
 414                         }
 415                         if (samAccountName[strlen(samAccountName)-1] == '$') {
 416                                 samAccountName[strlen(samAccountName)-1] = '\0';
 417                         }
 418                         saltbody = talloc_asprintf(mem_ctx, "%s.%s", samAccountName, dnsDomain);
 419
 420                         krb5_ret = krb5_make_principal(smb_krb5_context->krb5_context, &salt_principal, realm, "host", saltbody, NULL);
 421                 } else if (user_principal_name) {
 422                         char *p;
 423                         user_principal_name = talloc_strdup(mem_ctx, user_principal_name);
 424                         if (!user_principal_name) {
 425                                 talloc_free(mem_ctx);
 426                                 return LDB_ERR_OPERATIONS_ERROR;
 427                         } else {
 428                                 p = strchr(user_principal_name, '@');
 429                                 if (p) {
 430                                         p[0] = '\0';
 431                                 }
 432                                 krb5_ret = krb5_make_principal(smb_krb5_context->krb5_context, &salt_principal, realm, user_principal_name, NULL);
 433                         }
 434                 } else {
 435                         const char *samAccountName = ldb_msg_find_string(res->msgs[0], "samAccountName", NULL);
 436                         if (!samAccountName) {
 437                                 ldb_set_errstring(module,
 438                                                   talloc_asprintf(mem_ctx, "password_hash_handle: "
 439                                                                   "generation of new kerberos keys failed: %s has no samAccountName",
 440                                                                   ldb_dn_linearize(mem_ctx, dn)));
 441                                 talloc_free(mem_ctx);
 442                                 return LDB_ERR_OPERATIONS_ERROR;
 443                         }
 444                         krb5_ret = krb5_make_principal(smb_krb5_context->krb5_context, &salt_principal, realm, samAccountName, NULL);
 445                 }
 446
 447
 448                 if (krb5_ret) {
 449                         ldb_set_errstring(module,
 450                                           talloc_asprintf(mem_ctx, "password_hash_handle: "
 451                                                           "generation of a saltking principal failed: %s",
 452                                                           smb_get_krb5_error_message(smb_krb5_context->krb5_context,
 453                                                                                      krb5_ret, mem_ctx)));
 454                         talloc_free(mem_ctx);
 455                         return LDB_ERR_OPERATIONS_ERROR;
 456                 }
 457
 458                 /* TODO: We may wish to control the encryption types chosen in future */
 459                 krb5_ret = hdb_generate_key_set_password(smb_krb5_context->krb5_context,
 460                                                     salt_principal, sambaPassword, &keys, &num_keys);
 461                 krb5_free_principal(smb_krb5_context->krb5_context, salt_principal);
 462
 463                 if (krb5_ret) {
 464                         ldb_set_errstring(module,
 465                                           talloc_asprintf(mem_ctx, "password_hash_handle: "
 466                                                           "generation of new kerberos keys failed: %s",
 467                                                           smb_get_krb5_error_message(smb_krb5_context->krb5_context,
 468                                                                                      krb5_ret, mem_ctx)));
 469                         talloc_free(mem_ctx);
 470                         return LDB_ERR_OPERATIONS_ERROR;
 471                 }
 472
 473                 /* Walking
 474                  */
 475                 for (i=0; i < num_keys; i++) {
 476                         unsigned char *buf;
 477                         size_t buf_size;
 478                         size_t len;
 479                         struct ldb_val val;
 480
 481                         if (keys[i].key.keytype == ENCTYPE_ARCFOUR_HMAC) {
 482                                 /* We might end up doing this below:
 483                                  * This ensures we get the unicode
 484                                  * conversion right.  This should also
 485                                  * be fixed in the Heimdal libs */
 486                                 continue;
 487                         }
 488                         ASN1_MALLOC_ENCODE(Key, buf, buf_size, &keys[i], &len, krb5_ret);
 489
 490                         val.data = talloc_memdup(req, buf, len);
 491                         val.length = len;
 492                         free(buf);
 493                         if (!val.data || krb5_ret) {
 494                                 hdb_free_keys (smb_krb5_context->krb5_context, num_keys, keys);
 495                                 talloc_free(mem_ctx);
 496                                 return LDB_ERR_OPERATIONS_ERROR;
 497                         }
 498                         ret = ldb_msg_add_value(modify_msg, "krb5Key", &val);
 499                         if (ret != LDB_SUCCESS) {
 500                                 hdb_free_keys (smb_krb5_context->krb5_context, num_keys, keys);
 501                                 talloc_free(mem_ctx);
 502                                 return ret;
 503                         }
 504                 }
 505
 506                 hdb_free_keys (smb_krb5_context->krb5_context, num_keys, keys);
 507         }
 508
 509         /* Possibly kill off the cleartext or store it */
 510         CHECK_RET(ldb_msg_add_empty(modify_msg, "sambaPassword", LDB_FLAG_MOD_REPLACE));
 511
 512         if (sambaPassword && (pwdProperties & DOMAIN_PASSWORD_STORE_CLEARTEXT) &&
 513             (userAccountControl & UF_ENCRYPTED_TEXT_PASSWORD_ALLOWED)) {
 514                 CHECK_RET(ldb_msg_add_string(modify_msg, "sambaPassword", sambaPassword));
 515         }
 516
 517         /* Even if we didn't get a sambaPassword, we can still setup
 518          * krb5Key from the NT hash.
 519          *
 520          * This is an append, so it works with the 'continue' in the
 521          * unicode loop above, to use Samba's NT hash function, which
 522          * is more correct than Heimdal's
 523          */
 524         if (ntPwdHash) {
 525                 unsigned char *buf;
 526                 size_t buf_size;
 527                 size_t len;
 528                 struct ldb_val val;
 529                 Key key;
 530
 531                 key.mkvno = 0;
 532                 key.salt = NULL; /* No salt for this enc type */
 533
 534                 krb5_ret = krb5_keyblock_init(smb_krb5_context->krb5_context,
 535                                          ENCTYPE_ARCFOUR_HMAC,
 536                                          ntPwdHash->hash, sizeof(ntPwdHash->hash),
 537                                          &key.key);
 538                 if (krb5_ret) {
 539                         return LDB_ERR_OPERATIONS_ERROR;
 540                 }
 541                 ASN1_MALLOC_ENCODE(Key, buf, buf_size, &key, &len, krb5_ret);
 542                 krb5_free_keyblock_contents(smb_krb5_context->krb5_context,
 543                                             &key.key);
 544
 545                 val.data = talloc_memdup(req, buf, len);
 546                 val.length = len;
 547                 free(buf);
 548                 if (!val.data || ret) {
 549                         return LDB_ERR_OPERATIONS_ERROR;
 550                 }
 551                 CHECK_RET(ldb_msg_add_value(modify_msg, "krb5Key", &val));
 552         }
 553
 554         /* If the original caller did anything with pwdLastSet then skip this.  It could be an incoming samsync */
 555         if ((attribute = ldb_msg_find_element(msg, "pwdLastSet")) == NULL ) {
 556                 /* Update the password last set time */
 557                 unix_to_nt_time(&now_nt, now);
 558                 CHECK_RET(ldb_msg_add_empty(modify_msg, "pwdLastSet", LDB_FLAG_MOD_REPLACE));
 559                 CHECK_RET(samdb_msg_add_uint64(module->ldb, mem_ctx, modify_msg, "pwdLastSet", now_nt));
 560         }
 561
 562         /* If the original caller did anything with "msDS-KeyVersionNumber" then skip this.  It could be an incoming samsync */
 563         if ((attribute = ldb_msg_find_element(msg, "msDS-KeyVersionNumber")) == NULL ) {
 564                 if (kvno == 0) {
 565                         CHECK_RET(ldb_msg_add_empty(modify_msg, "msDS-KeyVersionNumber",
 566                                                     LDB_FLAG_MOD_REPLACE));
 567                         CHECK_RET(samdb_msg_add_uint(module->ldb, mem_ctx, modify_msg, "msDS-KeyVersionNumber", kvno + 1));
 568                 } else {
 569                         /* While we should be in a transaction, go one extra
 570                          * step in the dance for an 'atomic' increment.  This
 571                          * may be of value against remote LDAP servers.  (Note
 572                          * however that Mulitmaster replication stil offers no
 573                          * such guarantee) */
 574
 575                         struct ldb_val old_kvno, new_kvno;
 576                         old_kvno.data = (uint8_t *)talloc_asprintf(mem_ctx, "%u", kvno);
 577                         if (!old_kvno.data) {
 578                                 return -1;
 579                         }
 580                         old_kvno.length = strlen((char *)old_kvno.data);
 581
 582                         new_kvno.data = (uint8_t *)talloc_asprintf(mem_ctx, "%u", kvno + 1);
 583                         if (!new_kvno.data) {
 584                                 return -1;
 585                         }
 586                         new_kvno.length = strlen((char *)new_kvno.data);
 587
 588                         CHECK_RET(ldb_msg_add_empty(modify_msg, "msDS-KeyVersionNumber",
 589                                                     LDB_FLAG_MOD_DELETE));
 590                         CHECK_RET(ldb_msg_add_empty(modify_msg, "msDS-KeyVersionNumber",
 591                                                     LDB_FLAG_MOD_ADD));
 592                         modify_msg->elements[modify_msg->num_elements - 2].num_values = 1;
 593                         modify_msg->elements[modify_msg->num_elements - 2].values = &old_kvno;
 594                         modify_msg->elements[modify_msg->num_elements - 1].num_values = 1;
 595                         modify_msg->elements[modify_msg->num_elements - 1].values = &new_kvno;
 596                 }
 597         }
 598
 599         CHECK_RET(ldb_msg_add_empty(modify_msg, "sambaLMPwdHistory",
 600                                     LDB_FLAG_MOD_REPLACE));
 601         CHECK_RET(ldb_msg_add_empty(modify_msg, "sambaNTPwdHistory",
 602                                     LDB_FLAG_MOD_REPLACE));
 603
 604         /* If we have something to put into the history, or an old
 605          * history element to expire, update the history */
 606         if (pwdHistoryLength > 0 &&
 607             ((sambaNTPwdHistory_len > 0) || (sambaLMPwdHistory_len > 0)
 608              || lmOldHash || ntOldHash)) {
 609                 /* store the password history */
 610                 new_sambaLMPwdHistory = talloc_array(mem_ctx, struct samr_Password,
 611                                                 pwdHistoryLength);
 612                 if (!new_sambaLMPwdHistory) {
 613                         return LDB_ERR_OPERATIONS_ERROR;
 614                 }
 615                 new_sambaNTPwdHistory = talloc_array(mem_ctx, struct samr_Password,
 616                                                 pwdHistoryLength);
 617                 if (!new_sambaNTPwdHistory) {
 618                         return LDB_ERR_OPERATIONS_ERROR;
 619                 }
 620                 for (i=0;i<MIN(pwdHistoryLength-1, sambaLMPwdHistory_len);i++) {
 621                         new_sambaLMPwdHistory[i+1] = sambaLMPwdHistory[i];
 622                 }
 623                 for (i=0;i<MIN(pwdHistoryLength-1, sambaNTPwdHistory_len);i++) {
 624                         new_sambaNTPwdHistory[i+1] = sambaNTPwdHistory[i];
 625                 }
 626
 627                 /* Don't store 'long' passwords in the LM history,
 628                    but make sure to 'expire' one password off the other end */
 629                 if (lmOldHash) {
 630                         new_sambaLMPwdHistory[0] = *lmOldHash;
 631                 } else {
 632                         ZERO_STRUCT(new_sambaLMPwdHistory[0]);
 633                 }
 634                 sambaLMPwdHistory_len = MIN(sambaLMPwdHistory_len + 1, pwdHistoryLength);
 635
 636                 /* Likewise, we might not have a new NT password (lm
 637                  * only password change function) */
 638                 if (ntOldHash) {
 639                         new_sambaNTPwdHistory[0] = *ntOldHash;
 640                 } else {
 641                         ZERO_STRUCT(new_sambaNTPwdHistory[0]);
 642                 }
 643                 sambaNTPwdHistory_len = MIN(sambaNTPwdHistory_len + 1, pwdHistoryLength);
 644
 645                 CHECK_RET(samdb_msg_add_hashes(module->ldb, mem_ctx, modify_msg,
 646                                                "sambaLMPwdHistory",
 647                                                new_sambaLMPwdHistory,
 648                                                sambaLMPwdHistory_len));
 649
 650                 CHECK_RET(samdb_msg_add_hashes(module->ldb, mem_ctx, modify_msg,
 651                                                "sambaNTPwdHistory",
 652                                                new_sambaNTPwdHistory,
 653                                                sambaNTPwdHistory_len));
 654         }
 655
 656         /* Too much code above, we should check we got it close to reasonable */
 657         CHECK_RET(ldb_msg_sanity_check(modify_msg));
 658
 659         modify_request = talloc(mem_ctx, struct ldb_request);
 660         if (!modify_request) {
 661                 talloc_free(mem_ctx);
 662                 return LDB_ERR_OPERATIONS_ERROR;
 663         }
 664
 665         modify_request->operation = LDB_REQ_MODIFY;
 666         modify_request->op.mod.message = modify_msg;
 667         modify_request->controls = NULL;
 668
 669         ret = ldb_next_request(module, modify_request);
 670
 671         talloc_free(mem_ctx);
 672         return ret;
 673 }
 674
 675 /* add_record: do things with the sambaPassword attribute */
 676 static int password_hash_add(struct ldb_module *module, struct ldb_request *req)
 677 {
 678         const struct ldb_message *msg = req->op.add.message;
 679
 680         ldb_debug(module->ldb, LDB_DEBUG_TRACE, "password_hash_add_record\n");
 681
 682         if (ldb_dn_is_special(msg->dn)) { /* do not manipulate our control entries */
 683                 return ldb_next_request(module, req);
 684         }
 685
 686         return password_hash_handle(module, req, msg);
 687 }
 688
 689 /* modify_record: do things with the sambaPassword attribute */
 690 static int password_hash_modify(struct ldb_module *module, struct ldb_request *req)
 691 {
 692         const struct ldb_message *msg = req->op.mod.message;
 693
 694         ldb_debug(module->ldb, LDB_DEBUG_TRACE, "password_hash_modify_record\n");
 695
 696         if (ldb_dn_is_special(msg->dn)) { /* do not manipulate our control entries */
 697                 return ldb_next_request(module, req);
 698         }
 699
 700         return password_hash_handle(module, req, msg);
 701 }
 702
 703 static int password_hash_request(struct ldb_module *module, struct ldb_request *req)
 704 {
 705         switch (req->operation) {
 706
 707         case LDB_REQ_ADD:
 708                 return password_hash_add(module, req);
 709
 710         case LDB_REQ_MODIFY:
 711                 return password_hash_modify(module, req);
 712
 713         default:
 714                 return ldb_next_request(module, req);
 715
 716         }
 717 }
 718
 719 static const struct ldb_module_ops password_hash_ops = {
 720         .name          = "password_hash",
 721         .request       = password_hash_request
 722 };
 723
 724
 725 /* the init function */
 726 struct ldb_module *password_hash_module_init(struct ldb_context *ldb, const char *options[])
 727 {
 728         struct ldb_module *ctx;
 729
 730         ctx = talloc(ldb, struct ldb_module);
 731         if (!ctx)
 732                 return NULL;
 733
 734         ctx->private_data = NULL;
 735         ctx->ldb = ldb;
 736         ctx->prev = ctx->next = NULL;
 737         ctx->ops = &password_hash_ops;
 738
 739         return ctx;
 740 }