source4/kdc/db-glue.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Database Glue between Samba and the KDC
   5
   6    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005-2009
   7    Copyright (C) Simo Sorce <idra@samba.org> 2010
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "includes.h"
  25 #include "system/time.h"
  26 #include "../libds/common/flags.h"
  27 #include "lib/ldb/include/ldb.h"
  28 #include "librpc/gen_ndr/netlogon.h"
  29 #include "libcli/security/security.h"
  30 #include "auth/auth.h"
  31 #include "auth/credentials/credentials.h"
  32 #include "auth/auth_sam.h"
  33 #include "dsdb/samdb/samdb.h"
  34 #include "dsdb/common/util.h"
  35 #include "librpc/ndr/libndr.h"
  36 #include "librpc/gen_ndr/ndr_drsblobs.h"
  37 #include "librpc/gen_ndr/lsa.h"
  38 #include "libcli/auth/libcli_auth.h"
  39 #include "param/param.h"
  40 #include "../lib/crypto/md4.h"
  41 #include "system/kerberos.h"
  42 #include "auth/kerberos/kerberos.h"
  43 #include <hdb.h>
  44 #include "kdc/samba_kdc.h"
  45 #include "kdc/db-glue.h"
  46
  47 enum samba_kdc_ent_type
  48 { SAMBA_KDC_ENT_TYPE_CLIENT, SAMBA_KDC_ENT_TYPE_SERVER,
  49   SAMBA_KDC_ENT_TYPE_KRBTGT, SAMBA_KDC_ENT_TYPE_TRUST, SAMBA_KDC_ENT_TYPE_ANY };
  50
  51 enum trust_direction {
  52         UNKNOWN = 0,
  53         INBOUND = LSA_TRUST_DIRECTION_INBOUND,
  54         OUTBOUND = LSA_TRUST_DIRECTION_OUTBOUND
  55 };
  56
  57 static const char *trust_attrs[] = {
  58         "trustPartner",
  59         "trustAuthIncoming",
  60         "trustAuthOutgoing",
  61         "whenCreated",
  62         "msDS-SupportedEncryptionTypes",
  63         "trustAttributes",
  64         "trustDirection",
  65         "trustType",
  66         NULL
  67 };
  68
  69 static KerberosTime ldb_msg_find_krb5time_ldap_time(struct ldb_message *msg, const char *attr, KerberosTime default_val)
  70 {
  71     const char *tmp;
  72     const char *gentime;
  73     struct tm tm;
  74
  75     gentime = ldb_msg_find_attr_as_string(msg, attr, NULL);
  76     if (!gentime)
  77         return default_val;
  78
  79     tmp = strptime(gentime, "%Y%m%d%H%M%SZ", &tm);
  80     if (tmp == NULL) {
  81             return default_val;
  82     }
  83
  84     return timegm(&tm);
  85 }
  86
  87 static HDBFlags uf2HDBFlags(krb5_context context, uint32_t userAccountControl, enum samba_kdc_ent_type ent_type)
  88 {
  89         HDBFlags flags = int2HDBFlags(0);
  90
  91         /* we don't allow kadmin deletes */
  92         flags.immutable = 1;
  93
  94         /* mark the principal as invalid to start with */
  95         flags.invalid = 1;
  96
  97         flags.renewable = 1;
  98
  99         /* All accounts are servers, but this may be disabled again in the caller */
 100         flags.server = 1;
 101
 102         /* Account types - clear the invalid bit if it turns out to be valid */
 103         if (userAccountControl & UF_NORMAL_ACCOUNT) {
 104                 if (ent_type == SAMBA_KDC_ENT_TYPE_CLIENT || ent_type == SAMBA_KDC_ENT_TYPE_ANY) {
 105                         flags.client = 1;
 106                 }
 107                 flags.invalid = 0;
 108         }
 109
 110         if (userAccountControl & UF_INTERDOMAIN_TRUST_ACCOUNT) {
 111                 if (ent_type == SAMBA_KDC_ENT_TYPE_CLIENT || ent_type == SAMBA_KDC_ENT_TYPE_ANY) {
 112                         flags.client = 1;
 113                 }
 114                 flags.invalid = 0;
 115         }
 116         if (userAccountControl & UF_WORKSTATION_TRUST_ACCOUNT) {
 117                 if (ent_type == SAMBA_KDC_ENT_TYPE_CLIENT || ent_type == SAMBA_KDC_ENT_TYPE_ANY) {
 118                         flags.client = 1;
 119                 }
 120                 flags.invalid = 0;
 121         }
 122         if (userAccountControl & UF_SERVER_TRUST_ACCOUNT) {
 123                 if (ent_type == SAMBA_KDC_ENT_TYPE_CLIENT || ent_type == SAMBA_KDC_ENT_TYPE_ANY) {
 124                         flags.client = 1;
 125                 }
 126                 flags.invalid = 0;
 127         }
 128
 129         /* Not permitted to act as a client if disabled */
 130         if (userAccountControl & UF_ACCOUNTDISABLE) {
 131                 flags.client = 0;
 132         }
 133         if (userAccountControl & UF_LOCKOUT) {
 134                 flags.invalid = 1;
 135         }
 136 /*
 137         if (userAccountControl & UF_PASSWORD_NOTREQD) {
 138                 flags.invalid = 1;
 139         }
 140 */
 141 /*
 142         UF_PASSWORD_CANT_CHANGE and UF_ENCRYPTED_TEXT_PASSWORD_ALLOWED are irrelevent
 143 */
 144         if (userAccountControl & UF_TEMP_DUPLICATE_ACCOUNT) {
 145                 flags.invalid = 1;
 146         }
 147
 148 /* UF_DONT_EXPIRE_PASSWD and UF_USE_DES_KEY_ONLY handled in samba_kdc_message2entry() */
 149
 150 /*
 151         if (userAccountControl & UF_MNS_LOGON_ACCOUNT) {
 152                 flags.invalid = 1;
 153         }
 154 */
 155         if (userAccountControl & UF_SMARTCARD_REQUIRED) {
 156                 flags.require_hwauth = 1;
 157         }
 158         if (userAccountControl & UF_TRUSTED_FOR_DELEGATION) {
 159                 flags.ok_as_delegate = 1;
 160         }
 161         if (!(userAccountControl & UF_NOT_DELEGATED)) {
 162                 flags.forwardable = 1;
 163                 flags.proxiable = 1;
 164         }
 165
 166         if (userAccountControl & UF_DONT_REQUIRE_PREAUTH) {
 167                 flags.require_preauth = 0;
 168         } else {
 169                 flags.require_preauth = 1;
 170
 171         }
 172         return flags;
 173 }
 174
 175 static int samba_kdc_entry_destructor(struct samba_kdc_entry *p)
 176 {
 177     hdb_entry_ex *entry_ex = p->entry_ex;
 178     free_hdb_entry(&entry_ex->entry);
 179     return 0;
 180 }
 181
 182 static void samba_kdc_free_entry(krb5_context context, hdb_entry_ex *entry_ex)
 183 {
 184         /* this function is called only from hdb_free_entry().
 185          * Make sure we neutralize the destructor or we will
 186          * get a double free later when hdb_free_entry() will
 187          * try to call free_hdb_entry() */
 188         talloc_set_destructor(entry_ex->ctx, NULL);
 189
 190         /* now proceed to free the talloc part */
 191         talloc_free(entry_ex->ctx);
 192 }
 193
 194 static krb5_error_code samba_kdc_message2entry_keys(krb5_context context,
 195                                                     TALLOC_CTX *mem_ctx,
 196                                                     struct ldb_message *msg,
 197                                                     uint32_t rid,
 198                                                     bool is_rodc,
 199                                                     uint32_t userAccountControl,
 200                                                     enum samba_kdc_ent_type ent_type,
 201                                                     hdb_entry_ex *entry_ex)
 202 {
 203         krb5_error_code ret = 0;
 204         enum ndr_err_code ndr_err;
 205         struct samr_Password *hash;
 206         const struct ldb_val *sc_val;
 207         struct supplementalCredentialsBlob scb;
 208         struct supplementalCredentialsPackage *scpk = NULL;
 209         bool newer_keys = false;
 210         struct package_PrimaryKerberosBlob _pkb;
 211         struct package_PrimaryKerberosCtr3 *pkb3 = NULL;
 212         struct package_PrimaryKerberosCtr4 *pkb4 = NULL;
 213         uint16_t i;
 214         uint16_t allocated_keys = 0;
 215         int rodc_krbtgt_number = 0;
 216         uint32_t supported_enctypes;
 217
 218         if (rid == DOMAIN_RID_KRBTGT || is_rodc) {
 219                 /* KDCs (and KDCs on RODCs) use AES, but not DES */
 220                 supported_enctypes = ENC_ALL_TYPES;
 221                 supported_enctypes &= ~(ENC_CRC32|ENC_RSA_MD5);
 222         } else if (userAccountControl & (UF_PARTIAL_SECRETS_ACCOUNT|UF_SERVER_TRUST_ACCOUNT)) {
 223                 /* DCs and RODCs comptuer accounts use AES */
 224                 supported_enctypes = ENC_ALL_TYPES;
 225         } else if (ent_type == SAMBA_KDC_ENT_TYPE_CLIENT ||
 226                    (ent_type == SAMBA_KDC_ENT_TYPE_ANY)) {
 227                 /* for AS-REQ the client chooses the enc types it
 228                  * supports, and this will vary between computers a
 229                  * user logs in from.  However, some accounts may be
 230                  * banned from using DES, so allow the default to be
 231                  * overridden
 232                  *
 233                  * likewise for 'any' return as much as is supported,
 234                  * to export into a keytab */
 235                 supported_enctypes = ldb_msg_find_attr_as_uint(msg, "msDS-SupportedEncryptionTypes",
 236                                                                ENC_ALL_TYPES);
 237         } else {
 238                 /* However, if this is a TGS-REQ, then lock it down to
 239                  * a reasonable guess as to what the server can decode
 240                  * - we must use whatever is in
 241                  * "msDS-SupportedEncryptionTypes", or the 'old' set
 242                  * of keys (ie, what Windows 2000 supported) */
 243                 supported_enctypes = ldb_msg_find_attr_as_uint(msg, "msDS-SupportedEncryptionTypes",
 244                                                                ENC_CRC32 | ENC_RSA_MD5 | ENC_RC4_HMAC_MD5);
 245         }
 246
 247         /* Is this the krbtgt or a RODC krbtgt */
 248         if (is_rodc) {
 249                 rodc_krbtgt_number = ldb_msg_find_attr_as_int(msg, "msDS-SecondaryKrbTgtNumber", -1);
 250
 251                 if (rodc_krbtgt_number == -1) {
 252                         return EINVAL;
 253                 }
 254         }
 255
 256
 257         /* If UF_USE_DES_KEY_ONLY has been set, then don't allow use of the newer enc types */
 258         if (userAccountControl & UF_USE_DES_KEY_ONLY) {
 259                 /* However, this still won't allow use of DES, if we
 260                  * were told not to by msDS-SupportedEncTypes */
 261                 supported_enctypes &= ENC_CRC32|ENC_RSA_MD5;
 262         } else {
 263                 switch (ent_type) {
 264                 case SAMBA_KDC_ENT_TYPE_KRBTGT:
 265                 case SAMBA_KDC_ENT_TYPE_TRUST:
 266                         /* Unless a very special effort it made,
 267                          * disallow trust tickets to be DES encrypted,
 268                          * it's just too dangerous */
 269                         supported_enctypes &= ~(ENC_CRC32|ENC_RSA_MD5);
 270                         break;
 271                 default:
 272                         break;
 273                         /* No further restrictions */
 274                 }
 275         }
 276
 277         entry_ex->entry.keys.val = NULL;
 278         entry_ex->entry.keys.len = 0;
 279
 280         entry_ex->entry.kvno = ldb_msg_find_attr_as_int(msg, "msDS-KeyVersionNumber", 0);
 281         if (is_rodc) {
 282                 entry_ex->entry.kvno |= (rodc_krbtgt_number << 16);
 283         }
 284
 285         /* Get keys from the db */
 286
 287         hash = samdb_result_hash(mem_ctx, msg, "unicodePwd");
 288         sc_val = ldb_msg_find_ldb_val(msg, "supplementalCredentials");
 289
 290         /* unicodePwd for enctype 0x17 (23) if present */
 291         if (hash) {
 292                 allocated_keys++;
 293         }
 294
 295         /* supplementalCredentials if present */
 296         if (sc_val) {
 297                 ndr_err = ndr_pull_struct_blob_all(sc_val, mem_ctx, &scb,
 298                                                    (ndr_pull_flags_fn_t)ndr_pull_supplementalCredentialsBlob);
 299                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 300                         dump_data(0, sc_val->data, sc_val->length);
 301                         ret = EINVAL;
 302                         goto out;
 303                 }
 304
 305                 if (scb.sub.signature != SUPPLEMENTAL_CREDENTIALS_SIGNATURE) {
 306                         NDR_PRINT_DEBUG(supplementalCredentialsBlob, &scb);
 307                         ret = EINVAL;
 308                         goto out;
 309                 }
 310
 311                 for (i=0; i < scb.sub.num_packages; i++) {
 312                         if (strcmp("Primary:Kerberos-Newer-Keys", scb.sub.packages[i].name) == 0) {
 313                                 scpk = &scb.sub.packages[i];
 314                                 if (!scpk->data || !scpk->data[0]) {
 315                                         scpk = NULL;
 316                                         continue;
 317                                 }
 318                                 newer_keys = true;
 319                                 break;
 320                         } else if (strcmp("Primary:Kerberos", scb.sub.packages[i].name) == 0) {
 321                                 scpk = &scb.sub.packages[i];
 322                                 if (!scpk->data || !scpk->data[0]) {
 323                                         scpk = NULL;
 324                                 }
 325                                 /*
 326                                  * we don't break here in hope to find
 327                                  * a Kerberos-Newer-Keys package
 328                                  */
 329                         }
 330                 }
 331         }
 332         /*
 333          * Primary:Kerberos-Newer-Keys or Primary:Kerberos element
 334          * of supplementalCredentials
 335          */
 336         if (scpk) {
 337                 DATA_BLOB blob;
 338
 339                 blob = strhex_to_data_blob(mem_ctx, scpk->data);
 340                 if (!blob.data) {
 341                         ret = ENOMEM;
 342                         goto out;
 343                 }
 344
 345                 /* we cannot use ndr_pull_struct_blob_all() here, as w2k and w2k3 add padding bytes */
 346                 ndr_err = ndr_pull_struct_blob(&blob, mem_ctx, &_pkb,
 347                                                (ndr_pull_flags_fn_t)ndr_pull_package_PrimaryKerberosBlob);
 348                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 349                         ret = EINVAL;
 350                         krb5_set_error_message(context, ret, "samba_kdc_message2entry_keys: could not parse package_PrimaryKerberosBlob");
 351                         krb5_warnx(context, "samba_kdc_message2entry_keys: could not parse package_PrimaryKerberosBlob");
 352                         goto out;
 353                 }
 354
 355                 if (newer_keys && _pkb.version != 4) {
 356                         ret = EINVAL;
 357                         krb5_set_error_message(context, ret, "samba_kdc_message2entry_keys: Primary:Kerberos-Newer-Keys not version 4");
 358                         krb5_warnx(context, "samba_kdc_message2entry_keys: Primary:Kerberos-Newer-Keys not version 4");
 359                         goto out;
 360                 }
 361
 362                 if (!newer_keys && _pkb.version != 3) {
 363                         ret = EINVAL;
 364                         krb5_set_error_message(context, ret, "samba_kdc_message2entry_keys: could not parse Primary:Kerberos not version 3");
 365                         krb5_warnx(context, "samba_kdc_message2entry_keys: could not parse Primary:Kerberos not version 3");
 366                         goto out;
 367                 }
 368
 369                 if (_pkb.version == 4) {
 370                         pkb4 = &_pkb.ctr.ctr4;
 371                         allocated_keys += pkb4->num_keys;
 372                 } else if (_pkb.version == 3) {
 373                         pkb3 = &_pkb.ctr.ctr3;
 374                         allocated_keys += pkb3->num_keys;
 375                 }
 376         }
 377
 378         if (allocated_keys == 0) {
 379                 /* oh, no password.  Apparently (comment in
 380                  * hdb-ldap.c) this violates the ASN.1, but this
 381                  * allows an entry with no keys (yet). */
 382                 return 0;
 383         }
 384
 385         /* allocate space to decode into */
 386         entry_ex->entry.keys.len = 0;
 387         entry_ex->entry.keys.val = calloc(allocated_keys, sizeof(Key));
 388         if (entry_ex->entry.keys.val == NULL) {
 389                 ret = ENOMEM;
 390                 goto out;
 391         }
 392
 393         if (hash && (supported_enctypes & ENC_RC4_HMAC_MD5)) {
 394                 Key key;
 395
 396                 key.mkvno = 0;
 397                 key.salt = NULL; /* No salt for this enc type */
 398
 399                 ret = krb5_keyblock_init(context,
 400                                          ENCTYPE_ARCFOUR_HMAC,
 401                                          hash->hash, sizeof(hash->hash),
 402                                          &key.key);
 403                 if (ret) {
 404                         goto out;
 405                 }
 406
 407                 entry_ex->entry.keys.val[entry_ex->entry.keys.len] = key;
 408                 entry_ex->entry.keys.len++;
 409         }
 410
 411         if (pkb4) {
 412                 for (i=0; i < pkb4->num_keys; i++) {
 413                         Key key;
 414
 415                         if (!pkb4->keys[i].value) continue;
 416
 417                         if (!(kerberos_enctype_to_bitmap(pkb4->keys[i].keytype) & supported_enctypes)) {
 418                                 continue;
 419                         }
 420
 421                         key.mkvno = 0;
 422                         key.salt = NULL;
 423
 424                         if (pkb4->salt.string) {
 425                                 DATA_BLOB salt;
 426
 427                                 salt = data_blob_string_const(pkb4->salt.string);
 428
 429                                 key.salt = calloc(1, sizeof(*key.salt));
 430                                 if (key.salt == NULL) {
 431                                         ret = ENOMEM;
 432                                         goto out;
 433                                 }
 434
 435                                 key.salt->type = hdb_pw_salt;
 436
 437                                 ret = krb5_data_copy(&key.salt->salt, salt.data, salt.length);
 438                                 if (ret) {
 439                                         free(key.salt);
 440                                         key.salt = NULL;
 441                                         goto out;
 442                                 }
 443                         }
 444
 445                         /* TODO: maybe pass the iteration_count somehow... */
 446
 447                         ret = krb5_keyblock_init(context,
 448                                                  pkb4->keys[i].keytype,
 449                                                  pkb4->keys[i].value->data,
 450                                                  pkb4->keys[i].value->length,
 451                                                  &key.key);
 452                         if (ret == KRB5_PROG_ETYPE_NOSUPP) {
 453                                 DEBUG(2,("Unsupported keytype ignored - type %u\n",
 454                                          pkb4->keys[i].keytype));
 455                                 ret = 0;
 456                                 continue;
 457                         }
 458                         if (ret) {
 459                                 if (key.salt) {
 460                                         free_Salt(key.salt);
 461                                         free(key.salt);
 462                                         key.salt = NULL;
 463                                 }
 464                                 goto out;
 465                         }
 466
 467                         entry_ex->entry.keys.val[entry_ex->entry.keys.len] = key;
 468                         entry_ex->entry.keys.len++;
 469                 }
 470         } else if (pkb3) {
 471                 for (i=0; i < pkb3->num_keys; i++) {
 472                         Key key;
 473
 474                         if (!pkb3->keys[i].value) continue;
 475
 476                         if (!(kerberos_enctype_to_bitmap(pkb3->keys[i].keytype) & supported_enctypes)) {
 477                                 continue;
 478                         }
 479
 480                         key.mkvno = 0;
 481                         key.salt = NULL;
 482
 483                         if (pkb3->salt.string) {
 484                                 DATA_BLOB salt;
 485
 486                                 salt = data_blob_string_const(pkb3->salt.string);
 487
 488                                 key.salt = calloc(1, sizeof(*key.salt));
 489                                 if (key.salt == NULL) {
 490                                         ret = ENOMEM;
 491                                         goto out;
 492                                 }
 493
 494                                 key.salt->type = hdb_pw_salt;
 495
 496                                 ret = krb5_data_copy(&key.salt->salt, salt.data, salt.length);
 497                                 if (ret) {
 498                                         free(key.salt);
 499                                         key.salt = NULL;
 500                                         goto out;
 501                                 }
 502                         }
 503
 504                         ret = krb5_keyblock_init(context,
 505                                                  pkb3->keys[i].keytype,
 506                                                  pkb3->keys[i].value->data,
 507                                                  pkb3->keys[i].value->length,
 508                                                  &key.key);
 509                         if (ret) {
 510                                 if (key.salt) {
 511                                         free_Salt(key.salt);
 512                                         free(key.salt);
 513                                         key.salt = NULL;
 514                                 }
 515                                 goto out;
 516                         }
 517
 518                         entry_ex->entry.keys.val[entry_ex->entry.keys.len] = key;
 519                         entry_ex->entry.keys.len++;
 520                 }
 521         }
 522
 523 out:
 524         if (ret != 0) {
 525                 entry_ex->entry.keys.len = 0;
 526         }
 527         if (entry_ex->entry.keys.len == 0 && entry_ex->entry.keys.val) {
 528                 free(entry_ex->entry.keys.val);
 529                 entry_ex->entry.keys.val = NULL;
 530         }
 531         return ret;
 532 }
 533
 534 /*
 535  * Construct an hdb_entry from a directory entry.
 536  */
 537 static krb5_error_code samba_kdc_message2entry(krb5_context context,
 538                                          struct samba_kdc_db_context *kdc_db_ctx,
 539                                          TALLOC_CTX *mem_ctx, krb5_const_principal principal,
 540                                          enum samba_kdc_ent_type ent_type,
 541                                          struct ldb_dn *realm_dn,
 542                                          struct ldb_message *msg,
 543                                          hdb_entry_ex *entry_ex)
 544 {
 545         struct loadparm_context *lp_ctx = kdc_db_ctx->lp_ctx;
 546         uint32_t userAccountControl;
 547         unsigned int i;
 548         krb5_error_code ret = 0;
 549         krb5_boolean is_computer = FALSE;
 550         char *realm = strupper_talloc(mem_ctx, lpcfg_realm(lp_ctx));
 551
 552         struct samba_kdc_entry *p;
 553         NTTIME acct_expiry;
 554         NTSTATUS status;
 555
 556         uint32_t rid;
 557         bool is_rodc = false;
 558         struct ldb_message_element *objectclasses;
 559         struct ldb_val computer_val;
 560         const char *samAccountName = ldb_msg_find_attr_as_string(msg, "samAccountName", NULL);
 561         computer_val.data = discard_const_p(uint8_t,"computer");
 562         computer_val.length = strlen((const char *)computer_val.data);
 563
 564         if (ldb_msg_find_element(msg, "msDS-SecondaryKrbTgtNumber")) {
 565                 is_rodc = true;
 566         }
 567
 568         if (!samAccountName) {
 569                 ret = ENOENT;
 570                 krb5_set_error_message(context, ret, "samba_kdc_message2entry: no samAccountName present");
 571                 goto out;
 572         }
 573
 574         objectclasses = ldb_msg_find_element(msg, "objectClass");
 575
 576         if (objectclasses && ldb_msg_find_val(objectclasses, &computer_val)) {
 577                 is_computer = TRUE;
 578         }
 579
 580         memset(entry_ex, 0, sizeof(*entry_ex));
 581
 582         if (!realm) {
 583                 ret = ENOMEM;
 584                 krb5_set_error_message(context, ret, "talloc_strdup: out of memory");
 585                 goto out;
 586         }
 587
 588         p = talloc(mem_ctx, struct samba_kdc_entry);
 589         if (!p) {
 590                 ret = ENOMEM;
 591                 goto out;
 592         }
 593
 594         p->kdc_db_ctx = kdc_db_ctx;
 595         p->entry_ex = entry_ex;
 596         p->realm_dn = talloc_reference(p, realm_dn);
 597         if (!p->realm_dn) {
 598                 ret = ENOMEM;
 599                 goto out;
 600         }
 601
 602         talloc_set_destructor(p, samba_kdc_entry_destructor);
 603
 604         /* make sure we do not have bogus data in there */
 605         memset(&entry_ex->entry, 0, sizeof(hdb_entry));
 606
 607         entry_ex->ctx = p;
 608         entry_ex->free_entry = samba_kdc_free_entry;
 609
 610         userAccountControl = ldb_msg_find_attr_as_uint(msg, "userAccountControl", 0);
 611
 612
 613         entry_ex->entry.principal = malloc(sizeof(*(entry_ex->entry.principal)));
 614         if (ent_type == SAMBA_KDC_ENT_TYPE_ANY && principal == NULL) {
 615                 krb5_make_principal(context, &entry_ex->entry.principal, realm, samAccountName, NULL);
 616         } else {
 617                 ret = copy_Principal(principal, entry_ex->entry.principal);
 618                 if (ret) {
 619                         krb5_clear_error_message(context);
 620                         goto out;
 621                 }
 622
 623                 /* While we have copied the client principal, tests
 624                  * show that Win2k3 returns the 'corrected' realm, not
 625                  * the client-specified realm.  This code attempts to
 626                  * replace the client principal's realm with the one
 627                  * we determine from our records */
 628
 629                 /* this has to be with malloc() */
 630                 krb5_principal_set_realm(context, entry_ex->entry.principal, realm);
 631         }
 632
 633         /* First try and figure out the flags based on the userAccountControl */
 634         entry_ex->entry.flags = uf2HDBFlags(context, userAccountControl, ent_type);
 635
 636         /* Windows 2008 seems to enforce this (very sensible) rule by
 637          * default - don't allow offline attacks on a user's password
 638          * by asking for a ticket to them as a service (encrypted with
 639          * their probably patheticly insecure password) */
 640
 641         if (entry_ex->entry.flags.server
 642             && lpcfg_parm_bool(lp_ctx, NULL, "kdc", "require spn for service", true)) {
 643                 if (!is_computer && !ldb_msg_find_attr_as_string(msg, "servicePrincipalName", NULL)) {
 644                         entry_ex->entry.flags.server = 0;
 645                 }
 646         }
 647
 648         {
 649                 /* These (created_by, modified_by) parts of the entry are not relevant for Samba4's use
 650                  * of the Heimdal KDC.  They are stored in a the traditional
 651                  * DB for audit purposes, and still form part of the structure
 652                  * we must return */
 653
 654                 /* use 'whenCreated' */
 655                 entry_ex->entry.created_by.time = ldb_msg_find_krb5time_ldap_time(msg, "whenCreated", 0);
 656                 /* use 'kadmin' for now (needed by mit_samba) */
 657                 krb5_make_principal(context,
 658                                     &entry_ex->entry.created_by.principal,
 659                                     realm, "kadmin", NULL);
 660
 661                 entry_ex->entry.modified_by = (Event *) malloc(sizeof(Event));
 662                 if (entry_ex->entry.modified_by == NULL) {
 663                         ret = ENOMEM;
 664                         krb5_set_error_message(context, ret, "malloc: out of memory");
 665                         goto out;
 666                 }
 667
 668                 /* use 'whenChanged' */
 669                 entry_ex->entry.modified_by->time = ldb_msg_find_krb5time_ldap_time(msg, "whenChanged", 0);
 670                 /* use 'kadmin' for now (needed by mit_samba) */
 671                 krb5_make_principal(context,
 672                                     &entry_ex->entry.modified_by->principal,
 673                                     realm, "kadmin", NULL);
 674         }
 675
 676
 677         /* The lack of password controls etc applies to krbtgt by
 678          * virtue of being that particular RID */
 679         status = dom_sid_split_rid(NULL, samdb_result_dom_sid(mem_ctx, msg, "objectSid"), NULL, &rid);
 680
 681         if (!NT_STATUS_IS_OK(status)) {
 682                 ret = EINVAL;
 683                 goto out;
 684         }
 685
 686         if (rid == DOMAIN_RID_KRBTGT) {
 687                 entry_ex->entry.valid_end = NULL;
 688                 entry_ex->entry.pw_end = NULL;
 689
 690                 entry_ex->entry.flags.invalid = 0;
 691                 entry_ex->entry.flags.server = 1;
 692
 693                 /* Don't mark all requests for the krbtgt/realm as
 694                  * 'change password', as otherwise we could get into
 695                  * trouble, and not enforce the password expirty.
 696                  * Instead, only do it when request is for the kpasswd service */
 697                 if (ent_type == SAMBA_KDC_ENT_TYPE_SERVER
 698                     && principal->name.name_string.len == 2
 699                     && (strcmp(principal->name.name_string.val[0], "kadmin") == 0)
 700                     && (strcmp(principal->name.name_string.val[1], "changepw") == 0)
 701                     && lpcfg_is_my_domain_or_realm(lp_ctx, principal->realm)) {
 702                         entry_ex->entry.flags.change_pw = 1;
 703                 }
 704                 entry_ex->entry.flags.client = 0;
 705                 entry_ex->entry.flags.forwardable = 1;
 706                 entry_ex->entry.flags.ok_as_delegate = 1;
 707         } else if (is_rodc) {
 708                 /* The RODC krbtgt account is like the main krbtgt,
 709                  * but it does not have a changepw or kadmin
 710                  * service */
 711
 712                 entry_ex->entry.valid_end = NULL;
 713                 entry_ex->entry.pw_end = NULL;
 714
 715                 /* Also don't allow the RODC krbtgt to be a client (it should not be needed) */
 716                 entry_ex->entry.flags.client = 0;
 717                 entry_ex->entry.flags.invalid = 0;
 718                 entry_ex->entry.flags.server = 1;
 719
 720                 entry_ex->entry.flags.client = 0;
 721                 entry_ex->entry.flags.forwardable = 1;
 722                 entry_ex->entry.flags.ok_as_delegate = 0;
 723         } else if (entry_ex->entry.flags.server && ent_type == SAMBA_KDC_ENT_TYPE_SERVER) {
 724                 /* The account/password expiry only applies when the account is used as a
 725                  * client (ie password login), not when used as a server */
 726
 727                 /* Make very well sure we don't use this for a client,
 728                  * it could bypass the password restrictions */
 729                 entry_ex->entry.flags.client = 0;
 730
 731                 entry_ex->entry.valid_end = NULL;
 732                 entry_ex->entry.pw_end = NULL;
 733
 734         } else {
 735                 NTTIME must_change_time
 736                         = samdb_result_force_password_change(kdc_db_ctx->samdb, mem_ctx,
 737                                                              realm_dn, msg);
 738                 if (must_change_time == 0x7FFFFFFFFFFFFFFFULL) {
 739                         entry_ex->entry.pw_end = NULL;
 740                 } else {
 741                         entry_ex->entry.pw_end = malloc(sizeof(*entry_ex->entry.pw_end));
 742                         if (entry_ex->entry.pw_end == NULL) {
 743                                 ret = ENOMEM;
 744                                 goto out;
 745                         }
 746                         *entry_ex->entry.pw_end = nt_time_to_unix(must_change_time);
 747                 }
 748
 749                 acct_expiry = samdb_result_account_expires(msg);
 750                 if (acct_expiry == 0x7FFFFFFFFFFFFFFFULL) {
 751                         entry_ex->entry.valid_end = NULL;
 752                 } else {
 753                         entry_ex->entry.valid_end = malloc(sizeof(*entry_ex->entry.valid_end));
 754                         if (entry_ex->entry.valid_end == NULL) {
 755                                 ret = ENOMEM;
 756                                 goto out;
 757                         }
 758                         *entry_ex->entry.valid_end = nt_time_to_unix(acct_expiry);
 759                 }
 760         }
 761
 762         entry_ex->entry.valid_start = NULL;
 763
 764         entry_ex->entry.max_life = NULL;
 765
 766         entry_ex->entry.max_renew = NULL;
 767
 768         entry_ex->entry.generation = NULL;
 769
 770         /* Get keys from the db */
 771         ret = samba_kdc_message2entry_keys(context, p, msg,
 772                                            rid, is_rodc, userAccountControl,
 773                                            ent_type, entry_ex);
 774         if (ret) {
 775                 /* Could be bougus data in the entry, or out of memory */
 776                 goto out;
 777         }
 778
 779         entry_ex->entry.etypes = malloc(sizeof(*(entry_ex->entry.etypes)));
 780         if (entry_ex->entry.etypes == NULL) {
 781                 krb5_clear_error_message(context);
 782                 ret = ENOMEM;
 783                 goto out;
 784         }
 785         entry_ex->entry.etypes->len = entry_ex->entry.keys.len;
 786         entry_ex->entry.etypes->val = calloc(entry_ex->entry.etypes->len, sizeof(int));
 787         if (entry_ex->entry.etypes->val == NULL) {
 788                 krb5_clear_error_message(context);
 789                 ret = ENOMEM;
 790                 goto out;
 791         }
 792         for (i=0; i < entry_ex->entry.etypes->len; i++) {
 793                 entry_ex->entry.etypes->val[i] = entry_ex->entry.keys.val[i].key.keytype;
 794         }
 795
 796
 797         p->msg = talloc_steal(p, msg);
 798
 799 out:
 800         if (ret != 0) {
 801                 /* This doesn't free ent itself, that is for the eventual caller to do */
 802                 hdb_free_entry(context, entry_ex);
 803         } else {
 804                 talloc_steal(kdc_db_ctx, entry_ex->ctx);
 805         }
 806
 807         return ret;
 808 }
 809
 810 /*
 811  * Construct an hdb_entry from a directory entry.
 812  */
 813 static krb5_error_code samba_kdc_trust_message2entry(krb5_context context,
 814                                                struct samba_kdc_db_context *kdc_db_ctx,
 815                                                TALLOC_CTX *mem_ctx, krb5_const_principal principal,
 816                                                enum trust_direction direction,
 817                                                struct ldb_dn *realm_dn,
 818                                                struct ldb_message *msg,
 819                                                hdb_entry_ex *entry_ex)
 820 {
 821         struct loadparm_context *lp_ctx = kdc_db_ctx->lp_ctx;
 822         const char *dnsdomain;
 823         char *realm = strupper_talloc(mem_ctx, lpcfg_realm(lp_ctx));
 824         DATA_BLOB password_utf16;
 825         struct samr_Password password_hash;
 826         const struct ldb_val *password_val;
 827         struct trustAuthInOutBlob password_blob;
 828         struct samba_kdc_entry *p;
 829
 830         enum ndr_err_code ndr_err;
 831         int ret, trust_direction_flags;
 832         unsigned int i;
 833
 834         p = talloc(mem_ctx, struct samba_kdc_entry);
 835         if (!p) {
 836                 ret = ENOMEM;
 837                 goto out;
 838         }
 839
 840         p->kdc_db_ctx = kdc_db_ctx;
 841         p->entry_ex = entry_ex;
 842         p->realm_dn = realm_dn;
 843
 844         talloc_set_destructor(p, samba_kdc_entry_destructor);
 845
 846         /* make sure we do not have bogus data in there */
 847         memset(&entry_ex->entry, 0, sizeof(hdb_entry));
 848
 849         entry_ex->ctx = p;
 850         entry_ex->free_entry = samba_kdc_free_entry;
 851
 852         /* use 'whenCreated' */
 853         entry_ex->entry.created_by.time = ldb_msg_find_krb5time_ldap_time(msg, "whenCreated", 0);
 854         /* use 'kadmin' for now (needed by mit_samba) */
 855         krb5_make_principal(context,
 856                             &entry_ex->entry.created_by.principal,
 857                             realm, "kadmin", NULL);
 858
 859         entry_ex->entry.valid_start = NULL;
 860
 861         trust_direction_flags = ldb_msg_find_attr_as_int(msg, "trustDirection", 0);
 862
 863         if (direction == INBOUND) {
 864                 password_val = ldb_msg_find_ldb_val(msg, "trustAuthIncoming");
 865
 866         } else { /* OUTBOUND */
 867                 dnsdomain = ldb_msg_find_attr_as_string(msg, "trustPartner", NULL);
 868                 /* replace realm */
 869                 talloc_free(realm);
 870                 realm = strupper_talloc(mem_ctx, dnsdomain);
 871                 password_val = ldb_msg_find_ldb_val(msg, "trustAuthOutgoing");
 872         }
 873
 874         if (!password_val || !(trust_direction_flags & direction)) {
 875                 ret = ENOENT;
 876                 goto out;
 877         }
 878
 879         ndr_err = ndr_pull_struct_blob(password_val, mem_ctx, &password_blob,
 880                                            (ndr_pull_flags_fn_t)ndr_pull_trustAuthInOutBlob);
 881         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 882                 ret = EINVAL;
 883                 goto out;
 884         }
 885
 886         entry_ex->entry.kvno = -1;
 887         for (i=0; i < password_blob.count; i++) {
 888                 if (password_blob.current.array[i].AuthType == TRUST_AUTH_TYPE_VERSION) {
 889                         entry_ex->entry.kvno = password_blob.current.array[i].AuthInfo.version.version;
 890                 }
 891         }
 892
 893         for (i=0; i < password_blob.count; i++) {
 894                 if (password_blob.current.array[i].AuthType == TRUST_AUTH_TYPE_CLEAR) {
 895                         password_utf16 = data_blob_const(password_blob.current.array[i].AuthInfo.clear.password,
 896                                                          password_blob.current.array[i].AuthInfo.clear.size);
 897                         /* In the future, generate all sorts of
 898                          * hashes, but for now we can't safely convert
 899                          * the random strings windows uses into
 900                          * utf8 */
 901
 902                         /* but as it is utf16 already, we can get the NT password/arcfour-hmac-md5 key */
 903                         mdfour(password_hash.hash, password_utf16.data, password_utf16.length);
 904                         break;
 905                 } else if (password_blob.current.array[i].AuthType == TRUST_AUTH_TYPE_NT4OWF) {
 906                         password_hash = password_blob.current.array[i].AuthInfo.nt4owf.password;
 907                         break;
 908                 }
 909         }
 910
 911         if (i < password_blob.count) {
 912                 Key key;
 913                 /* Must have found a cleartext or MD4 password */
 914                 entry_ex->entry.keys.val = calloc(1, sizeof(Key));
 915
 916                 key.mkvno = 0;
 917                 key.salt = NULL; /* No salt for this enc type */
 918
 919                 if (entry_ex->entry.keys.val == NULL) {
 920                         ret = ENOMEM;
 921                         goto out;
 922                 }
 923
 924                 ret = krb5_keyblock_init(context,
 925                                          ENCTYPE_ARCFOUR_HMAC,
 926                                          password_hash.hash, sizeof(password_hash.hash),
 927                                          &key.key);
 928
 929                 entry_ex->entry.keys.val[entry_ex->entry.keys.len] = key;
 930                 entry_ex->entry.keys.len++;
 931         }
 932
 933         entry_ex->entry.principal = malloc(sizeof(*(entry_ex->entry.principal)));
 934
 935         ret = copy_Principal(principal, entry_ex->entry.principal);
 936         if (ret) {
 937                 krb5_clear_error_message(context);
 938                 goto out;
 939         }
 940
 941         /* While we have copied the client principal, tests
 942          * show that Win2k3 returns the 'corrected' realm, not
 943          * the client-specified realm.  This code attempts to
 944          * replace the client principal's realm with the one
 945          * we determine from our records */
 946
 947         krb5_principal_set_realm(context, entry_ex->entry.principal, realm);
 948         entry_ex->entry.flags = int2HDBFlags(0);
 949         entry_ex->entry.flags.immutable = 1;
 950         entry_ex->entry.flags.invalid = 0;
 951         entry_ex->entry.flags.server = 1;
 952         entry_ex->entry.flags.require_preauth = 1;
 953
 954         entry_ex->entry.pw_end = NULL;
 955
 956         entry_ex->entry.max_life = NULL;
 957
 958         entry_ex->entry.max_renew = NULL;
 959
 960         entry_ex->entry.generation = NULL;
 961
 962         entry_ex->entry.etypes = malloc(sizeof(*(entry_ex->entry.etypes)));
 963         if (entry_ex->entry.etypes == NULL) {
 964                 krb5_clear_error_message(context);
 965                 ret = ENOMEM;
 966                 goto out;
 967         }
 968         entry_ex->entry.etypes->len = entry_ex->entry.keys.len;
 969         entry_ex->entry.etypes->val = calloc(entry_ex->entry.etypes->len, sizeof(int));
 970         if (entry_ex->entry.etypes->val == NULL) {
 971                 krb5_clear_error_message(context);
 972                 ret = ENOMEM;
 973                 goto out;
 974         }
 975         for (i=0; i < entry_ex->entry.etypes->len; i++) {
 976                 entry_ex->entry.etypes->val[i] = entry_ex->entry.keys.val[i].key.keytype;
 977         }
 978
 979
 980         p->msg = talloc_steal(p, msg);
 981
 982 out:
 983         if (ret != 0) {
 984                 /* This doesn't free ent itself, that is for the eventual caller to do */
 985                 hdb_free_entry(context, entry_ex);
 986         } else {
 987                 talloc_steal(kdc_db_ctx, entry_ex->ctx);
 988         }
 989
 990         return ret;
 991
 992 }
 993
 994 static krb5_error_code samba_kdc_lookup_trust(krb5_context context, struct ldb_context *ldb_ctx,
 995                                         TALLOC_CTX *mem_ctx,
 996                                         const char *realm,
 997                                         struct ldb_dn *realm_dn,
 998                                         struct ldb_message **pmsg)
 999 {
1000         int lret;
1001         krb5_error_code ret;
1002         char *filter = NULL;
1003         const char * const *attrs = trust_attrs;
1004
1005         struct ldb_result *res = NULL;
1006         filter = talloc_asprintf(mem_ctx, "(&(objectClass=trustedDomain)(|(flatname=%s)(trustPartner=%s)))", realm, realm);
1007
1008         if (!filter) {
1009                 ret = ENOMEM;
1010                 krb5_set_error_message(context, ret, "talloc_asprintf: out of memory");
1011                 return ret;
1012         }
1013
1014         lret = ldb_search(ldb_ctx, mem_ctx, &res,
1015                           ldb_get_default_basedn(ldb_ctx),
1016                           LDB_SCOPE_SUBTREE, attrs, "%s", filter);
1017         if (lret != LDB_SUCCESS) {
1018                 DEBUG(3, ("Failed to search for %s: %s\n", filter, ldb_errstring(ldb_ctx)));
1019                 return HDB_ERR_NOENTRY;
1020         } else if (res->count == 0 || res->count > 1) {
1021                 DEBUG(3, ("Failed find a single entry for %s: got %d\n", filter, res->count));
1022                 talloc_free(res);
1023                 return HDB_ERR_NOENTRY;
1024         }
1025         talloc_steal(mem_ctx, res->msgs);
1026         *pmsg = res->msgs[0];
1027         talloc_free(res);
1028         return 0;
1029 }
1030
1031 static krb5_error_code samba_kdc_lookup_client(krb5_context context,
1032                                                 struct samba_kdc_db_context *kdc_db_ctx,
1033                                                 TALLOC_CTX *mem_ctx,
1034                                                 krb5_const_principal principal,
1035                                                 const char **attrs,
1036                                                 struct ldb_dn **realm_dn,
1037                                                 struct ldb_message **msg) {
1038         NTSTATUS nt_status;
1039         char *principal_string;
1040         krb5_error_code ret;
1041
1042         ret = krb5_unparse_name(context, principal, &principal_string);
1043
1044         if (ret != 0) {
1045                 return ret;
1046         }
1047
1048         nt_status = sam_get_results_principal(kdc_db_ctx->samdb,
1049                                               mem_ctx, principal_string, attrs,
1050                                               realm_dn, msg);
1051         free(principal_string);
1052         if (NT_STATUS_EQUAL(nt_status, NT_STATUS_NO_SUCH_USER)) {
1053                 return HDB_ERR_NOENTRY;
1054         } else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_NO_MEMORY)) {
1055                 return ENOMEM;
1056         } else if (!NT_STATUS_IS_OK(nt_status)) {
1057                 return EINVAL;
1058         }
1059
1060         return ret;
1061 }
1062
1063 static krb5_error_code samba_kdc_fetch_client(krb5_context context,
1064                                                struct samba_kdc_db_context *kdc_db_ctx,
1065                                                TALLOC_CTX *mem_ctx,
1066                                                krb5_const_principal principal,
1067                                                hdb_entry_ex *entry_ex) {
1068         struct ldb_dn *realm_dn;
1069         krb5_error_code ret;
1070         struct ldb_message *msg = NULL;
1071
1072         ret = samba_kdc_lookup_client(context, kdc_db_ctx,
1073                                        mem_ctx, principal, user_attrs,
1074                                        &realm_dn, &msg);
1075         if (ret != 0) {
1076                 return ret;
1077         }
1078
1079         ret = samba_kdc_message2entry(context, kdc_db_ctx, mem_ctx,
1080                                        principal, SAMBA_KDC_ENT_TYPE_CLIENT,
1081                                        realm_dn, msg, entry_ex);
1082         return ret;
1083 }
1084
1085 static krb5_error_code samba_kdc_fetch_krbtgt(krb5_context context,
1086                                               struct samba_kdc_db_context *kdc_db_ctx,
1087                                               TALLOC_CTX *mem_ctx,
1088                                               krb5_const_principal principal,
1089                                               uint32_t krbtgt_number,
1090                                               hdb_entry_ex *entry_ex)
1091 {
1092         struct loadparm_context *lp_ctx = kdc_db_ctx->lp_ctx;
1093         krb5_error_code ret;
1094         struct ldb_message *msg = NULL;
1095         struct ldb_dn *realm_dn = ldb_get_default_basedn(kdc_db_ctx->samdb);
1096
1097         krb5_principal alloc_principal = NULL;
1098         if (principal->name.name_string.len != 2
1099             || (strcmp(principal->name.name_string.val[0], KRB5_TGS_NAME) != 0)) {
1100                 /* Not a krbtgt */
1101                 return HDB_ERR_NOENTRY;
1102         }
1103
1104         /* krbtgt case.  Either us or a trusted realm */
1105
1106         if (lpcfg_is_my_domain_or_realm(lp_ctx, principal->realm)
1107             && lpcfg_is_my_domain_or_realm(lp_ctx, principal->name.name_string.val[1])) {
1108                 /* us, or someone quite like us */
1109                 /* Cludge, cludge cludge.  If the realm part of krbtgt/realm,
1110                  * is in our db, then direct the caller at our primary
1111                  * krbtgt */
1112
1113                 int lret;
1114                 char *realm_fixed;
1115
1116                 if (krbtgt_number == kdc_db_ctx->my_krbtgt_number) {
1117                         lret = dsdb_search_one(kdc_db_ctx->samdb, mem_ctx,
1118                                                &msg, kdc_db_ctx->krbtgt_dn, LDB_SCOPE_BASE,
1119                                                krbtgt_attrs, 0,
1120                                                "(objectClass=user)");
1121                 } else {
1122                         /* We need to look up an RODC krbtgt (perhaps
1123                          * ours, if we are an RODC, perhaps another
1124                          * RODC if we are a read-write DC */
1125                         lret = dsdb_search_one(kdc_db_ctx->samdb, mem_ctx,
1126                                                &msg, realm_dn, LDB_SCOPE_SUBTREE,
1127                                                krbtgt_attrs,
1128                                                DSDB_SEARCH_SHOW_EXTENDED_DN,
1129                                                "(&(objectClass=user)(msDS-SecondaryKrbTgtNumber=%u))", (unsigned)(krbtgt_number));
1130                 }
1131
1132                 if (lret == LDB_ERR_NO_SUCH_OBJECT) {
1133                         krb5_warnx(context, "samba_kdc_fetch: could not find KRBTGT number %u in DB!",
1134                                    (unsigned)(krbtgt_number));
1135                         krb5_set_error_message(context, HDB_ERR_NOENTRY,
1136                                                "samba_kdc_fetch: could not find KRBTGT number %u in DB!",
1137                                                (unsigned)(krbtgt_number));
1138                         return HDB_ERR_NOENTRY;
1139                 } else if (lret != LDB_SUCCESS) {
1140                         krb5_warnx(context, "samba_kdc_fetch: could not find KRBTGT number %u in DB!",
1141                                    (unsigned)(krbtgt_number));
1142                         krb5_set_error_message(context, HDB_ERR_NOENTRY,
1143                                                "samba_kdc_fetch: could not find KRBTGT number %u in DB!",
1144                                                (unsigned)(krbtgt_number));
1145                         return HDB_ERR_NOENTRY;
1146                 }
1147
1148                 realm_fixed = strupper_talloc(mem_ctx, lpcfg_realm(lp_ctx));
1149                 if (!realm_fixed) {
1150                         ret = ENOMEM;
1151                         krb5_set_error_message(context, ret, "strupper_talloc: out of memory");
1152                         return ret;
1153                 }
1154
1155                 ret = krb5_copy_principal(context, principal, &alloc_principal);
1156                 if (ret) {
1157                         return ret;
1158                 }
1159
1160                 free(alloc_principal->name.name_string.val[1]);
1161                 alloc_principal->name.name_string.val[1] = strdup(realm_fixed);
1162                 talloc_free(realm_fixed);
1163                 if (!alloc_principal->name.name_string.val[1]) {
1164                         ret = ENOMEM;
1165                         krb5_set_error_message(context, ret, "samba_kdc_fetch: strdup() failed!");
1166                         return ret;
1167                 }
1168                 principal = alloc_principal;
1169
1170                 ret = samba_kdc_message2entry(context, kdc_db_ctx, mem_ctx,
1171                                         principal, SAMBA_KDC_ENT_TYPE_KRBTGT,
1172                                         realm_dn, msg, entry_ex);
1173                 if (ret != 0) {
1174                         krb5_warnx(context, "samba_kdc_fetch: self krbtgt message2entry failed");
1175                 }
1176                 return ret;
1177
1178         } else {
1179                 enum trust_direction direction = UNKNOWN;
1180                 const char *realm = NULL;
1181
1182                 /* Either an inbound or outbound trust */
1183
1184                 if (strcasecmp(lpcfg_realm(lp_ctx), principal->realm) == 0) {
1185                         /* look for inbound trust */
1186                         direction = INBOUND;
1187                         realm = principal->name.name_string.val[1];
1188                 } else if (strcasecmp(lpcfg_realm(lp_ctx), principal->name.name_string.val[1]) == 0) {
1189                         /* look for outbound trust */
1190                         direction = OUTBOUND;
1191                         realm = principal->realm;
1192                 } else {
1193                         krb5_warnx(context, "samba_kdc_fetch: not our realm for trusts ('%s', '%s')",
1194                                    principal->realm, principal->name.name_string.val[1]);
1195                         krb5_set_error_message(context, HDB_ERR_NOENTRY, "samba_kdc_fetch: not our realm for trusts ('%s', '%s')",
1196                                                principal->realm, principal->name.name_string.val[1]);
1197                         return HDB_ERR_NOENTRY;
1198                 }
1199
1200                 /* Trusted domains are under CN=system */
1201
1202                 ret = samba_kdc_lookup_trust(context, kdc_db_ctx->samdb,
1203                                        mem_ctx,
1204                                        realm, realm_dn, &msg);
1205
1206                 if (ret != 0) {
1207                         krb5_warnx(context, "samba_kdc_fetch: could not find principal in DB");
1208                         krb5_set_error_message(context, ret, "samba_kdc_fetch: could not find principal in DB");
1209                         return ret;
1210                 }
1211
1212                 ret = samba_kdc_trust_message2entry(context, kdc_db_ctx, mem_ctx,
1213                                               principal, direction,
1214                                               realm_dn, msg, entry_ex);
1215                 if (ret != 0) {
1216                         krb5_warnx(context, "samba_kdc_fetch: trust_message2entry failed");
1217                 }
1218                 return ret;
1219         }
1220
1221 }
1222
1223 static krb5_error_code samba_kdc_lookup_server(krb5_context context,
1224                                                 struct samba_kdc_db_context *kdc_db_ctx,
1225                                                 TALLOC_CTX *mem_ctx,
1226                                                 krb5_const_principal principal,
1227                                                 const char **attrs,
1228                                                 struct ldb_dn **realm_dn,
1229                                                 struct ldb_message **msg)
1230 {
1231         krb5_error_code ret;
1232         const char *realm;
1233         if (principal->name.name_string.len >= 2) {
1234                 /* 'normal server' case */
1235                 int ldb_ret;
1236                 NTSTATUS nt_status;
1237                 struct ldb_dn *user_dn;
1238                 char *principal_string;
1239
1240                 ret = krb5_unparse_name_flags(context, principal,
1241                                               KRB5_PRINCIPAL_UNPARSE_NO_REALM,
1242                                               &principal_string);
1243                 if (ret != 0) {
1244                         return ret;
1245                 }
1246
1247                 /* At this point we may find the host is known to be
1248                  * in a different realm, so we should generate a
1249                  * referral instead */
1250                 nt_status = crack_service_principal_name(kdc_db_ctx->samdb,
1251                                                          mem_ctx, principal_string,
1252                                                          &user_dn, realm_dn);
1253                 free(principal_string);
1254
1255                 if (!NT_STATUS_IS_OK(nt_status)) {
1256                         return HDB_ERR_NOENTRY;
1257                 }
1258
1259                 ldb_ret = dsdb_search_one(kdc_db_ctx->samdb,
1260                                           mem_ctx,
1261                                           msg, user_dn, LDB_SCOPE_BASE,
1262                                           attrs, DSDB_SEARCH_SHOW_EXTENDED_DN, "(objectClass=*)");
1263                 if (ldb_ret != LDB_SUCCESS) {
1264                         return HDB_ERR_NOENTRY;
1265                 }
1266
1267         } else {
1268                 int lret;
1269                 char *filter = NULL;
1270                 char *short_princ;
1271                 /* server as client principal case, but we must not lookup userPrincipalNames */
1272                 *realm_dn = ldb_get_default_basedn(kdc_db_ctx->samdb);
1273                 realm = krb5_principal_get_realm(context, principal);
1274
1275                 /* TODO: Check if it is our realm, otherwise give referall */
1276
1277                 ret = krb5_unparse_name_flags(context, principal,  KRB5_PRINCIPAL_UNPARSE_NO_REALM, &short_princ);
1278
1279                 if (ret != 0) {
1280                         krb5_set_error_message(context, ret, "samba_kdc_lookup_principal: could not parse principal");
1281                         krb5_warnx(context, "samba_kdc_lookup_principal: could not parse principal");
1282                         return ret;
1283                 }
1284
1285                 lret = dsdb_search_one(kdc_db_ctx->samdb, mem_ctx, msg,
1286                                        *realm_dn, LDB_SCOPE_SUBTREE,
1287                                        attrs,
1288                                        DSDB_SEARCH_SHOW_EXTENDED_DN,
1289                                        "(&(objectClass=user)(samAccountName=%s))",
1290                                        ldb_binary_encode_string(mem_ctx, short_princ));
1291                 free(short_princ);
1292                 if (lret == LDB_ERR_NO_SUCH_OBJECT) {
1293                         DEBUG(3, ("Failed find a entry for %s\n", filter));
1294                         return HDB_ERR_NOENTRY;
1295                 }
1296                 if (lret != LDB_SUCCESS) {
1297                         DEBUG(3, ("Failed single search for for %s - %s\n",
1298                                   filter, ldb_errstring(kdc_db_ctx->samdb)));
1299                         return HDB_ERR_NOENTRY;
1300                 }
1301         }
1302
1303         return 0;
1304 }
1305
1306 static krb5_error_code samba_kdc_fetch_server(krb5_context context,
1307                                                struct samba_kdc_db_context *kdc_db_ctx,
1308                                                TALLOC_CTX *mem_ctx,
1309                                                krb5_const_principal principal,
1310                                                hdb_entry_ex *entry_ex)
1311 {
1312         krb5_error_code ret;
1313         struct ldb_dn *realm_dn;
1314         struct ldb_message *msg;
1315
1316         ret = samba_kdc_lookup_server(context, kdc_db_ctx, mem_ctx, principal,
1317                                        server_attrs, &realm_dn, &msg);
1318         if (ret != 0) {
1319                 return ret;
1320         }
1321
1322         ret = samba_kdc_message2entry(context, kdc_db_ctx, mem_ctx,
1323                                 principal, SAMBA_KDC_ENT_TYPE_SERVER,
1324                                 realm_dn, msg, entry_ex);
1325         if (ret != 0) {
1326                 krb5_warnx(context, "samba_kdc_fetch: message2entry failed");
1327         }
1328
1329         return ret;
1330 }
1331
1332 krb5_error_code samba_kdc_fetch(krb5_context context,
1333                                 struct samba_kdc_db_context *kdc_db_ctx,
1334                                 krb5_const_principal principal,
1335                                 unsigned flags,
1336                                 unsigned kvno,
1337                                 hdb_entry_ex *entry_ex)
1338 {
1339         krb5_error_code ret = HDB_ERR_NOENTRY;
1340         TALLOC_CTX *mem_ctx;
1341         unsigned int krbtgt_number;
1342         if (flags & HDB_F_KVNO_SPECIFIED) {
1343                 krbtgt_number = kvno >> 16;
1344                 if (kdc_db_ctx->rodc) {
1345                         if (krbtgt_number != kdc_db_ctx->my_krbtgt_number) {
1346                                 return HDB_ERR_NOT_FOUND_HERE;
1347                         }
1348                 }
1349         } else {
1350                 krbtgt_number = kdc_db_ctx->my_krbtgt_number;
1351         }
1352
1353         mem_ctx = talloc_named(kdc_db_ctx, 0, "samba_kdc_fetch context");
1354         if (!mem_ctx) {
1355                 ret = ENOMEM;
1356                 krb5_set_error_message(context, ret, "samba_kdc_fetch: talloc_named() failed!");
1357                 return ret;
1358         }
1359
1360         if (flags & HDB_F_GET_CLIENT) {
1361                 ret = samba_kdc_fetch_client(context, kdc_db_ctx, mem_ctx, principal, entry_ex);
1362                 if (ret != HDB_ERR_NOENTRY) goto done;
1363         }
1364         if (flags & HDB_F_GET_SERVER) {
1365                 /* krbtgt fits into this situation for trusted realms, and for resolving different versions of our own realm name */
1366                 ret = samba_kdc_fetch_krbtgt(context, kdc_db_ctx, mem_ctx, principal, krbtgt_number, entry_ex);
1367                 if (ret != HDB_ERR_NOENTRY) goto done;
1368
1369                 /* We return 'no entry' if it does not start with krbtgt/, so move to the common case quickly */
1370                 ret = samba_kdc_fetch_server(context, kdc_db_ctx, mem_ctx, principal, entry_ex);
1371                 if (ret != HDB_ERR_NOENTRY) goto done;
1372         }
1373         if (flags & HDB_F_GET_KRBTGT) {
1374                 ret = samba_kdc_fetch_krbtgt(context, kdc_db_ctx, mem_ctx, principal, krbtgt_number, entry_ex);
1375                 if (ret != HDB_ERR_NOENTRY) goto done;
1376         }
1377
1378 done:
1379         talloc_free(mem_ctx);
1380         return ret;
1381 }
1382
1383 struct samba_kdc_seq {
1384         unsigned int index;
1385         unsigned int count;
1386         struct ldb_message **msgs;
1387         struct ldb_dn *realm_dn;
1388 };
1389
1390 static krb5_error_code samba_kdc_seq(krb5_context context,
1391                                      struct samba_kdc_db_context *kdc_db_ctx,
1392                                      hdb_entry_ex *entry)
1393 {
1394         krb5_error_code ret;
1395         struct samba_kdc_seq *priv = kdc_db_ctx->seq_ctx;
1396         TALLOC_CTX *mem_ctx;
1397         hdb_entry_ex entry_ex;
1398         memset(&entry_ex, '\0', sizeof(entry_ex));
1399
1400         if (!priv) {
1401                 return HDB_ERR_NOENTRY;
1402         }
1403
1404         mem_ctx = talloc_named(priv, 0, "samba_kdc_seq context");
1405
1406         if (!mem_ctx) {
1407                 ret = ENOMEM;
1408                 krb5_set_error_message(context, ret, "samba_kdc_seq: talloc_named() failed!");
1409                 return ret;
1410         }
1411
1412         if (priv->index < priv->count) {
1413                 ret = samba_kdc_message2entry(context, kdc_db_ctx, mem_ctx,
1414                                         NULL, SAMBA_KDC_ENT_TYPE_ANY,
1415                                         priv->realm_dn, priv->msgs[priv->index++], entry);
1416         } else {
1417                 ret = HDB_ERR_NOENTRY;
1418         }
1419
1420         if (ret != 0) {
1421                 TALLOC_FREE(priv);
1422                 kdc_db_ctx->seq_ctx = NULL;
1423         } else {
1424                 talloc_free(mem_ctx);
1425         }
1426
1427         return ret;
1428 }
1429
1430 krb5_error_code samba_kdc_firstkey(krb5_context context,
1431                                    struct samba_kdc_db_context *kdc_db_ctx,
1432                                    hdb_entry_ex *entry)
1433 {
1434         struct ldb_context *ldb_ctx = kdc_db_ctx->samdb;
1435         struct samba_kdc_seq *priv = kdc_db_ctx->seq_ctx;
1436         char *realm;
1437         struct ldb_result *res = NULL;
1438         krb5_error_code ret;
1439         TALLOC_CTX *mem_ctx;
1440         int lret;
1441
1442         if (priv) {
1443                 TALLOC_FREE(priv);
1444                 kdc_db_ctx->seq_ctx = NULL;
1445         }
1446
1447         priv = (struct samba_kdc_seq *) talloc(kdc_db_ctx, struct samba_kdc_seq);
1448         if (!priv) {
1449                 ret = ENOMEM;
1450                 krb5_set_error_message(context, ret, "talloc: out of memory");
1451                 return ret;
1452         }
1453
1454         priv->index = 0;
1455         priv->msgs = NULL;
1456         priv->realm_dn = ldb_get_default_basedn(ldb_ctx);
1457         priv->count = 0;
1458
1459         mem_ctx = talloc_named(priv, 0, "samba_kdc_firstkey context");
1460
1461         if (!mem_ctx) {
1462                 ret = ENOMEM;
1463                 krb5_set_error_message(context, ret, "samba_kdc_firstkey: talloc_named() failed!");
1464                 return ret;
1465         }
1466
1467         ret = krb5_get_default_realm(context, &realm);
1468         if (ret != 0) {
1469                 TALLOC_FREE(priv);
1470                 return ret;
1471         }
1472
1473         lret = ldb_search(ldb_ctx, priv, &res,
1474                           priv->realm_dn, LDB_SCOPE_SUBTREE, user_attrs,
1475                           "(objectClass=user)");
1476
1477         if (lret != LDB_SUCCESS) {
1478                 TALLOC_FREE(priv);
1479                 return HDB_ERR_NOENTRY;
1480         }
1481
1482         priv->count = res->count;
1483         priv->msgs = talloc_steal(priv, res->msgs);
1484         talloc_free(res);
1485
1486         kdc_db_ctx->seq_ctx = priv;
1487
1488         ret = samba_kdc_seq(context, kdc_db_ctx, entry);
1489
1490         if (ret != 0) {
1491                 TALLOC_FREE(priv);
1492                 kdc_db_ctx->seq_ctx = NULL;
1493         } else {
1494                 talloc_free(mem_ctx);
1495         }
1496         return ret;
1497 }
1498
1499 krb5_error_code samba_kdc_nextkey(krb5_context context,
1500                                   struct samba_kdc_db_context *kdc_db_ctx,
1501                                   hdb_entry_ex *entry)
1502 {
1503         return samba_kdc_seq(context, kdc_db_ctx, entry);
1504 }
1505
1506 /* Check if a given entry may delegate or do s4u2self to this target principal
1507  *
1508  * This is currently a very nasty hack - allowing only delegation to itself.
1509  *
1510  * This is shared between the constrained delegation and S4U2Self code.
1511  */
1512 krb5_error_code
1513 samba_kdc_check_identical_client_and_server(krb5_context context,
1514                                             struct samba_kdc_db_context *kdc_db_ctx,
1515                                             hdb_entry_ex *entry,
1516                                             krb5_const_principal target_principal)
1517 {
1518         krb5_error_code ret;
1519         krb5_principal enterprise_prinicpal = NULL;
1520         struct ldb_dn *realm_dn;
1521         struct ldb_message *msg;
1522         struct dom_sid *orig_sid;
1523         struct dom_sid *target_sid;
1524         struct samba_kdc_entry *p = talloc_get_type(entry->ctx, struct samba_kdc_entry);
1525         const char *delegation_check_attrs[] = {
1526                 "objectSid", NULL
1527         };
1528
1529         TALLOC_CTX *mem_ctx = talloc_named(kdc_db_ctx, 0, "samba_kdc_check_constrained_delegation");
1530
1531         if (!mem_ctx) {
1532                 ret = ENOMEM;
1533                 krb5_set_error_message(context, ret, "samba_kdc_fetch: talloc_named() failed!");
1534                 return ret;
1535         }
1536
1537         if (target_principal->name.name_type == KRB5_NT_ENTERPRISE_PRINCIPAL) {
1538                 /* Need to reparse the enterprise principal to find the real target */
1539                 if (target_principal->name.name_string.len != 1) {
1540                         ret = KRB5_PARSE_MALFORMED;
1541                         krb5_set_error_message(context, ret, "samba_kdc_check_constrained_delegation: request for delegation to enterprise principal with wrong (%d) number of components",
1542                                                target_principal->name.name_string.len);
1543                         talloc_free(mem_ctx);
1544                         return ret;
1545                 }
1546                 ret = krb5_parse_name(context, target_principal->name.name_string.val[0],
1547                                       &enterprise_prinicpal);
1548                 if (ret) {
1549                         talloc_free(mem_ctx);
1550                         return ret;
1551                 }
1552                 target_principal = enterprise_prinicpal;
1553         }
1554
1555         ret = samba_kdc_lookup_server(context, kdc_db_ctx, mem_ctx, target_principal,
1556                                        delegation_check_attrs, &realm_dn, &msg);
1557
1558         krb5_free_principal(context, enterprise_prinicpal);
1559
1560         if (ret != 0) {
1561                 talloc_free(mem_ctx);
1562                 return ret;
1563         }
1564
1565         orig_sid = samdb_result_dom_sid(mem_ctx, p->msg, "objectSid");
1566         target_sid = samdb_result_dom_sid(mem_ctx, msg, "objectSid");
1567
1568         /* Allow delegation to the same principal, even if by a different
1569          * name.  The easy and safe way to prove this is by SID
1570          * comparison */
1571         if (!(orig_sid && target_sid && dom_sid_equal(orig_sid, target_sid))) {
1572                 talloc_free(mem_ctx);
1573                 return KRB5KDC_ERR_BADOPTION;
1574         }
1575
1576         talloc_free(mem_ctx);
1577         return ret;
1578 }
1579
1580 /* Certificates printed by a the Certificate Authority might have a
1581  * slightly different form of the user principal name to that in the
1582  * database.  Allow a mismatch where they both refer to the same
1583  * SID */
1584
1585 krb5_error_code
1586 samba_kdc_check_pkinit_ms_upn_match(krb5_context context,
1587                                     struct samba_kdc_db_context *kdc_db_ctx,
1588                                      hdb_entry_ex *entry,
1589                                      krb5_const_principal certificate_principal)
1590 {
1591         krb5_error_code ret;
1592         struct ldb_dn *realm_dn;
1593         struct ldb_message *msg;
1594         struct dom_sid *orig_sid;
1595         struct dom_sid *target_sid;
1596         struct samba_kdc_entry *p = talloc_get_type(entry->ctx, struct samba_kdc_entry);
1597         const char *ms_upn_check_attrs[] = {
1598                 "objectSid", NULL
1599         };
1600
1601         TALLOC_CTX *mem_ctx = talloc_named(kdc_db_ctx, 0, "samba_kdc_check_pkinit_ms_upn_match");
1602
1603         if (!mem_ctx) {
1604                 ret = ENOMEM;
1605                 krb5_set_error_message(context, ret, "samba_kdc_fetch: talloc_named() failed!");
1606                 return ret;
1607         }
1608
1609         ret = samba_kdc_lookup_client(context, kdc_db_ctx,
1610                                        mem_ctx, certificate_principal,
1611                                        ms_upn_check_attrs, &realm_dn, &msg);
1612
1613         if (ret != 0) {
1614                 talloc_free(mem_ctx);
1615                 return ret;
1616         }
1617
1618         orig_sid = samdb_result_dom_sid(mem_ctx, p->msg, "objectSid");
1619         target_sid = samdb_result_dom_sid(mem_ctx, msg, "objectSid");
1620
1621         /* Consider these to be the same principal, even if by a different
1622          * name.  The easy and safe way to prove this is by SID
1623          * comparison */
1624         if (!(orig_sid && target_sid && dom_sid_equal(orig_sid, target_sid))) {
1625                 talloc_free(mem_ctx);
1626                 return KRB5_KDC_ERR_CLIENT_NAME_MISMATCH;
1627         }
1628
1629         talloc_free(mem_ctx);
1630         return ret;
1631 }
1632
1633 NTSTATUS samba_kdc_setup_db_ctx(TALLOC_CTX *mem_ctx, struct samba_kdc_base_context *base_ctx,
1634                                 struct samba_kdc_db_context **kdc_db_ctx_out)
1635 {
1636         int ldb_ret;
1637         struct ldb_message *msg;
1638         struct auth_session_info *session_info;
1639         struct samba_kdc_db_context *kdc_db_ctx;
1640         /* The idea here is very simple.  Using Kerberos to
1641          * authenticate the KDC to the LDAP server is higly likely to
1642          * be circular.
1643          *
1644          * In future we may set this up to use EXERNAL and SSL
1645          * certificates, for now it will almost certainly be NTLMSSP_SET_USERNAME
1646         */
1647
1648         kdc_db_ctx = talloc_zero(mem_ctx, struct samba_kdc_db_context);
1649         if (kdc_db_ctx == NULL) {
1650                 return NT_STATUS_NO_MEMORY;
1651         }
1652         kdc_db_ctx->ev_ctx = base_ctx->ev_ctx;
1653         kdc_db_ctx->lp_ctx = base_ctx->lp_ctx;
1654
1655         session_info = system_session(kdc_db_ctx->lp_ctx);
1656         if (session_info == NULL) {
1657                 return NT_STATUS_INTERNAL_ERROR;
1658         }
1659
1660         /* Setup the link to LDB */
1661         kdc_db_ctx->samdb = samdb_connect(kdc_db_ctx, base_ctx->ev_ctx,
1662                                           base_ctx->lp_ctx, session_info, 0);
1663         if (kdc_db_ctx->samdb == NULL) {
1664                 DEBUG(1, ("hdb_samba4_create: Cannot open samdb for KDC backend!"));
1665                 talloc_free(kdc_db_ctx);
1666                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
1667         }
1668
1669         /* Find out our own krbtgt kvno */
1670         ldb_ret = samdb_rodc(kdc_db_ctx->samdb, &kdc_db_ctx->rodc);
1671         if (ldb_ret != LDB_SUCCESS) {
1672                 DEBUG(1, ("hdb_samba4_create: Cannot determine if we are an RODC in KDC backend: %s\n",
1673                           ldb_errstring(kdc_db_ctx->samdb)));
1674                 talloc_free(kdc_db_ctx);
1675                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
1676         }
1677         if (kdc_db_ctx->rodc) {
1678                 int my_krbtgt_number;
1679                 const char *secondary_keytab[] = { "msDS-SecondaryKrbTgtNumber", NULL };
1680                 struct ldb_dn *account_dn;
1681                 struct ldb_dn *server_dn = samdb_server_dn(kdc_db_ctx->samdb, kdc_db_ctx);
1682                 if (!server_dn) {
1683                         DEBUG(1, ("hdb_samba4_create: Cannot determine server DN in KDC backend: %s\n",
1684                                   ldb_errstring(kdc_db_ctx->samdb)));
1685                         talloc_free(kdc_db_ctx);
1686                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
1687                 }
1688
1689                 ldb_ret = samdb_reference_dn(kdc_db_ctx->samdb, kdc_db_ctx, server_dn,
1690                                              "serverReference", &account_dn);
1691                 if (ldb_ret != LDB_SUCCESS) {
1692                         DEBUG(1, ("hdb_samba4_create: Cannot determine server account in KDC backend: %s\n",
1693                                   ldb_errstring(kdc_db_ctx->samdb)));
1694                         talloc_free(kdc_db_ctx);
1695                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
1696                 }
1697
1698                 ldb_ret = samdb_reference_dn(kdc_db_ctx->samdb, kdc_db_ctx, account_dn,
1699                                              "msDS-KrbTgtLink", &kdc_db_ctx->krbtgt_dn);
1700                 talloc_free(account_dn);
1701                 if (ldb_ret != LDB_SUCCESS) {
1702                         DEBUG(1, ("hdb_samba4_create: Cannot determine RODC krbtgt account in KDC backend: %s\n",
1703                                   ldb_errstring(kdc_db_ctx->samdb)));
1704                         talloc_free(kdc_db_ctx);
1705                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
1706                 }
1707
1708                 ldb_ret = dsdb_search_one(kdc_db_ctx->samdb, kdc_db_ctx,
1709                                           &msg, kdc_db_ctx->krbtgt_dn, LDB_SCOPE_BASE,
1710                                           secondary_keytab,
1711                                           0,
1712                                           "(&(objectClass=user)(msDS-SecondaryKrbTgtNumber=*))");
1713                 if (ldb_ret != LDB_SUCCESS) {
1714                         DEBUG(1, ("hdb_samba4_create: Cannot read krbtgt account %s in KDC backend to get msDS-SecondaryKrbTgtNumber: %s: %s\n",
1715                                   ldb_dn_get_linearized(kdc_db_ctx->krbtgt_dn),
1716                                   ldb_errstring(kdc_db_ctx->samdb),
1717                                   ldb_strerror(ldb_ret)));
1718                         talloc_free(kdc_db_ctx);
1719                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
1720                 }
1721                 my_krbtgt_number = ldb_msg_find_attr_as_int(msg, "msDS-SecondaryKrbTgtNumber", -1);
1722                 if (my_krbtgt_number == -1) {
1723                         DEBUG(1, ("hdb_samba4_create: Cannot read msDS-SecondaryKrbTgtNumber from krbtgt account %s in KDC backend: got %d\n",
1724                                   ldb_dn_get_linearized(kdc_db_ctx->krbtgt_dn),
1725                                   my_krbtgt_number));
1726                         talloc_free(kdc_db_ctx);
1727                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
1728                 }
1729                 kdc_db_ctx->my_krbtgt_number = my_krbtgt_number;
1730
1731         } else {
1732                 kdc_db_ctx->my_krbtgt_number = 0;
1733                 ldb_ret = dsdb_search_one(kdc_db_ctx->samdb, kdc_db_ctx,
1734                                           &msg, NULL, LDB_SCOPE_SUBTREE,
1735                                           krbtgt_attrs,
1736                                           DSDB_SEARCH_SHOW_EXTENDED_DN,
1737                                           "(&(objectClass=user)(samAccountName=krbtgt))");
1738
1739                 if (ldb_ret != LDB_SUCCESS) {
1740                         DEBUG(1, ("samba_kdc_fetch: could not find own KRBTGT in DB: %s\n", ldb_errstring(kdc_db_ctx->samdb)));
1741                         talloc_free(kdc_db_ctx);
1742                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
1743                 }
1744                 kdc_db_ctx->krbtgt_dn = talloc_steal(kdc_db_ctx, msg->dn);
1745                 kdc_db_ctx->my_krbtgt_number = 0;
1746                 talloc_free(msg);
1747         }
1748         *kdc_db_ctx_out = kdc_db_ctx;
1749         return NT_STATUS_OK;
1750 }