source4/dsdb/repl/replicated_objects.c

   1 /*
   2    Unix SMB/CIFS mplementation.
   3    Helper functions for applying replicated objects
   4
   5    Copyright (C) Stefan Metzmacher <metze@samba.org> 2007
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19
  20 */
  21
  22 #include "includes.h"
  23 #include "dsdb/samdb/samdb.h"
  24 #include "lib/ldb/include/ldb_errors.h"
  25 #include "lib/util/dlinklist.h"
  26 #include "librpc/gen_ndr/ndr_misc.h"
  27 #include "librpc/gen_ndr/ndr_drsuapi.h"
  28 #include "librpc/gen_ndr/ndr_drsblobs.h"
  29 #include "lib/crypto/crypto.h"
  30 #include "libcli/auth/libcli_auth.h"
  31
  32 static WERROR dsdb_decrypt_attribute_value(TALLOC_CTX *mem_ctx,
  33                                            const DATA_BLOB *gensec_skey,
  34                                            bool rid_crypt,
  35                                            uint32_t rid,
  36                                            DATA_BLOB *in,
  37                                            DATA_BLOB *out)
  38 {
  39         DATA_BLOB confounder;
  40         DATA_BLOB enc_buffer;
  41
  42         struct MD5Context md5;
  43         uint8_t _enc_key[16];
  44         DATA_BLOB enc_key;
  45
  46         DATA_BLOB dec_buffer;
  47
  48         uint32_t crc32_given;
  49         uint32_t crc32_calc;
  50         DATA_BLOB checked_buffer;
  51
  52         DATA_BLOB plain_buffer;
  53
  54         /*
  55          * users with rid == 0 should not exist
  56          */
  57         if (rid_crypt && rid == 0) {
  58                 return WERR_DS_DRA_INVALID_PARAMETER;
  59         }
  60
  61         /*
  62          * the first 16 bytes at the beginning are the confounder
  63          * followed by the 4 byte crc32 checksum
  64          */
  65         if (in->length < 20) {
  66                 return WERR_DS_DRA_INVALID_PARAMETER;
  67         }
  68         confounder = data_blob_const(in->data, 16);
  69         enc_buffer = data_blob_const(in->data + 16, in->length - 16);
  70
  71         /*
  72          * build the encryption key md5 over the session key followed
  73          * by the confounder
  74          *
  75          * here the gensec session key is used and
  76          * not the dcerpc ncacn_ip_tcp "SystemLibraryDTC" key!
  77          */
  78         enc_key = data_blob_const(_enc_key, sizeof(_enc_key));
  79         MD5Init(&md5);
  80         MD5Update(&md5, gensec_skey->data, gensec_skey->length);
  81         MD5Update(&md5, confounder.data, confounder.length);
  82         MD5Final(enc_key.data, &md5);
  83
  84         /*
  85          * copy the encrypted buffer part and
  86          * decrypt it using the created encryption key using arcfour
  87          */
  88         dec_buffer = data_blob_const(enc_buffer.data, enc_buffer.length);
  89         arcfour_crypt_blob(dec_buffer.data, dec_buffer.length, &enc_key);
  90
  91         /*
  92          * the first 4 byte are the crc32 checksum
  93          * of the remaining bytes
  94          */
  95         crc32_given = IVAL(dec_buffer.data, 0);
  96         crc32_calc = crc32_calc_buffer(dec_buffer.data + 4 , dec_buffer.length - 4);
  97         if (crc32_given != crc32_calc) {
  98                 return WERR_SEC_E_DECRYPT_FAILURE;
  99         }
 100         checked_buffer = data_blob_const(dec_buffer.data + 4, dec_buffer.length - 4);
 101
 102         plain_buffer = data_blob_talloc(mem_ctx, checked_buffer.data, checked_buffer.length);
 103         W_ERROR_HAVE_NO_MEMORY(plain_buffer.data);
 104
 105         /*
 106          * The following rid_crypt obfuscation isn't session specific
 107          * and not really needed here, because we allways know the rid of the
 108          * user account.
 109          *
 110          * But for the rest of samba it's easier when we remove this static
 111          * obfuscation here
 112          */
 113         if (rid_crypt) {
 114                 uint32_t i, num_hashes;
 115
 116                 if ((checked_buffer.length % 16) != 0) {
 117                         return WERR_DS_DRA_INVALID_PARAMETER;
 118                 }
 119
 120                 num_hashes = plain_buffer.length / 16;
 121                 for (i = 0; i < num_hashes; i++) {
 122                         uint32_t offset = i * 16;
 123                         sam_rid_crypt(rid, checked_buffer.data + offset, plain_buffer.data + offset, 0);
 124                 }
 125         }
 126
 127         *out = plain_buffer;
 128         return WERR_OK;
 129 }
 130
 131 static WERROR dsdb_decrypt_attribute(const DATA_BLOB *gensec_skey,
 132                                      uint32_t rid,
 133                                      struct drsuapi_DsReplicaAttribute *attr)
 134 {
 135         WERROR status;
 136         TALLOC_CTX *mem_ctx;
 137         DATA_BLOB *enc_data;
 138         DATA_BLOB plain_data;
 139         bool rid_crypt = false;
 140
 141         if (attr->value_ctr.num_values == 0) {
 142                 return WERR_OK;
 143         }
 144
 145         switch (attr->attid) {
 146         case DRSUAPI_ATTRIBUTE_dBCSPwd:
 147         case DRSUAPI_ATTRIBUTE_unicodePwd:
 148         case DRSUAPI_ATTRIBUTE_ntPwdHistory:
 149         case DRSUAPI_ATTRIBUTE_lmPwdHistory:
 150                 rid_crypt = true;
 151                 break;
 152         case DRSUAPI_ATTRIBUTE_supplementalCredentials:
 153         case DRSUAPI_ATTRIBUTE_priorValue:
 154         case DRSUAPI_ATTRIBUTE_currentValue:
 155         case DRSUAPI_ATTRIBUTE_trustAuthOutgoing:
 156         case DRSUAPI_ATTRIBUTE_trustAuthIncoming:
 157         case DRSUAPI_ATTRIBUTE_initialAuthOutgoing:
 158         case DRSUAPI_ATTRIBUTE_initialAuthIncoming:
 159                 break;
 160         default:
 161                 return WERR_OK;
 162         }
 163
 164         if (attr->value_ctr.num_values > 1) {
 165                 return WERR_DS_DRA_INVALID_PARAMETER;
 166         }
 167
 168         if (!attr->value_ctr.values[0].blob) {
 169                 return WERR_DS_DRA_INVALID_PARAMETER;
 170         }
 171
 172         mem_ctx         = attr->value_ctr.values[0].blob;
 173         enc_data        = attr->value_ctr.values[0].blob;
 174
 175         status = dsdb_decrypt_attribute_value(mem_ctx,
 176                                               gensec_skey,
 177                                               rid_crypt,
 178                                               rid,
 179                                               enc_data,
 180                                               &plain_data);
 181         W_ERROR_NOT_OK_RETURN(status);
 182
 183         talloc_free(attr->value_ctr.values[0].blob->data);
 184         *attr->value_ctr.values[0].blob = plain_data;
 185
 186         return WERR_OK;
 187 }
 188
 189 static WERROR dsdb_convert_object(struct ldb_context *ldb,
 190                                   const struct dsdb_schema *schema,
 191                                   struct dsdb_extended_replicated_objects *ctr,
 192                                   const struct drsuapi_DsReplicaObjectListItemEx *in,
 193                                   const DATA_BLOB *gensec_skey,
 194                                   TALLOC_CTX *mem_ctx,
 195                                   struct dsdb_extended_replicated_object *out)
 196 {
 197         NTSTATUS nt_status;
 198         WERROR status;
 199         uint32_t i;
 200         struct ldb_message *msg;
 201         struct replPropertyMetaDataBlob *md;
 202         struct ldb_val guid_value;
 203         NTTIME whenChanged = 0;
 204         time_t whenChanged_t;
 205         const char *whenChanged_s;
 206         const char *rdn_name = NULL;
 207         const struct ldb_val *rdn_value = NULL;
 208         const struct dsdb_attribute *rdn_attr = NULL;
 209         uint32_t rdn_attid;
 210         struct drsuapi_DsReplicaAttribute *name_a = NULL;
 211         struct drsuapi_DsReplicaMetaData *name_d = NULL;
 212         struct replPropertyMetaData1 *rdn_m = NULL;
 213         struct dom_sid *sid = NULL;
 214         uint32_t rid = 0;
 215         int ret;
 216
 217         if (!in->object.identifier) {
 218                 return WERR_FOOBAR;
 219         }
 220
 221         if (!in->object.identifier->dn || !in->object.identifier->dn[0]) {
 222                 return WERR_FOOBAR;
 223         }
 224
 225         if (in->object.attribute_ctr.num_attributes != 0 && !in->meta_data_ctr) {
 226                 return WERR_FOOBAR;
 227         }
 228
 229         if (in->object.attribute_ctr.num_attributes != in->meta_data_ctr->count) {
 230                 return WERR_FOOBAR;
 231         }
 232
 233         sid = &in->object.identifier->sid;
 234         if (sid->num_auths > 0) {
 235                 rid = sid->sub_auths[sid->num_auths - 1];
 236         }
 237
 238         msg = ldb_msg_new(mem_ctx);
 239         W_ERROR_HAVE_NO_MEMORY(msg);
 240
 241         msg->dn                 = ldb_dn_new(msg, ldb, in->object.identifier->dn);
 242         W_ERROR_HAVE_NO_MEMORY(msg->dn);
 243
 244         rdn_name        = ldb_dn_get_rdn_name(msg->dn);
 245         rdn_attr        = dsdb_attribute_by_lDAPDisplayName(schema, rdn_name);
 246         if (!rdn_attr) {
 247                 return WERR_FOOBAR;
 248         }
 249         rdn_attid       = rdn_attr->attributeID_id;
 250         rdn_value       = ldb_dn_get_rdn_val(msg->dn);
 251
 252         msg->num_elements       = in->object.attribute_ctr.num_attributes;
 253         msg->elements           = talloc_array(msg, struct ldb_message_element,
 254                                                msg->num_elements);
 255         W_ERROR_HAVE_NO_MEMORY(msg->elements);
 256
 257         md = talloc(mem_ctx, struct replPropertyMetaDataBlob);
 258         W_ERROR_HAVE_NO_MEMORY(md);
 259
 260         md->version             = 1;
 261         md->reserved            = 0;
 262         md->ctr.ctr1.count      = in->meta_data_ctr->count;
 263         md->ctr.ctr1.reserved   = 0;
 264         md->ctr.ctr1.array      = talloc_array(mem_ctx,
 265                                                struct replPropertyMetaData1,
 266                                                md->ctr.ctr1.count + 1); /* +1 because of the RDN attribute */
 267         W_ERROR_HAVE_NO_MEMORY(md->ctr.ctr1.array);
 268
 269         for (i=0; i < in->meta_data_ctr->count; i++) {
 270                 struct drsuapi_DsReplicaAttribute *a;
 271                 struct drsuapi_DsReplicaMetaData *d;
 272                 struct replPropertyMetaData1 *m;
 273                 struct ldb_message_element *e;
 274
 275                 a = &in->object.attribute_ctr.attributes[i];
 276                 d = &in->meta_data_ctr->meta_data[i];
 277                 m = &md->ctr.ctr1.array[i];
 278                 e = &msg->elements[i];
 279
 280                 status = dsdb_decrypt_attribute(gensec_skey, rid, a);
 281                 W_ERROR_NOT_OK_RETURN(status);
 282
 283                 status = dsdb_attribute_drsuapi_to_ldb(schema, a, msg->elements, e);
 284                 W_ERROR_NOT_OK_RETURN(status);
 285
 286                 m->attid                        = a->attid;
 287                 m->version                      = d->version;
 288                 m->originating_change_time      = d->originating_change_time;
 289                 m->originating_invocation_id    = d->originating_invocation_id;
 290                 m->originating_usn              = d->originating_usn;
 291                 m->local_usn                    = 0;
 292
 293                 if (d->originating_change_time > whenChanged) {
 294                         whenChanged = d->originating_change_time;
 295                 }
 296
 297                 if (a->attid == DRSUAPI_ATTRIBUTE_name) {
 298                         name_a = a;
 299                         name_d = d;
 300                         rdn_m = &md->ctr.ctr1.array[md->ctr.ctr1.count];
 301                 }
 302         }
 303
 304         if (rdn_m) {
 305                 ret = ldb_msg_add_value(msg, rdn_attr->lDAPDisplayName, rdn_value, NULL);
 306                 if (ret != LDB_SUCCESS) {
 307                         return WERR_FOOBAR;
 308                 }
 309
 310                 rdn_m->attid                            = rdn_attid;
 311                 rdn_m->version                          = name_d->version;
 312                 rdn_m->originating_change_time          = name_d->originating_change_time;
 313                 rdn_m->originating_invocation_id        = name_d->originating_invocation_id;
 314                 rdn_m->originating_usn                  = name_d->originating_usn;
 315                 rdn_m->local_usn                        = 0;
 316                 md->ctr.ctr1.count++;
 317
 318         }
 319
 320         whenChanged_t = nt_time_to_unix(whenChanged);
 321         whenChanged_s = ldb_timestring(msg, whenChanged_t);
 322         W_ERROR_HAVE_NO_MEMORY(whenChanged_s);
 323
 324         nt_status = ndr_push_struct_blob(&guid_value, msg, &in->object.identifier->guid,
 325                                          (ndr_push_flags_fn_t)ndr_push_GUID);
 326         if (!NT_STATUS_IS_OK(nt_status)) {
 327                 return ntstatus_to_werror(nt_status);
 328         }
 329
 330         out->msg                = msg;
 331         out->guid_value         = guid_value;
 332         out->when_changed       = whenChanged_s;
 333         out->meta_data          = md;
 334         return WERR_OK;
 335 }
 336
 337 WERROR dsdb_extended_replicated_objects_commit(struct ldb_context *ldb,
 338                                                const char *partition_dn,
 339                                                const struct drsuapi_DsReplicaOIDMapping_Ctr *mapping_ctr,
 340                                                uint32_t object_count,
 341                                                const struct drsuapi_DsReplicaObjectListItemEx *first_object,
 342                                                uint32_t linked_attributes_count,
 343                                                const struct drsuapi_DsReplicaLinkedAttribute *linked_attributes,
 344                                                const struct repsFromTo1 *source_dsa,
 345                                                const struct drsuapi_DsReplicaCursor2CtrEx *uptodateness_vector,
 346                                                const DATA_BLOB *gensec_skey,
 347                                                TALLOC_CTX *mem_ctx,
 348                                                struct dsdb_extended_replicated_objects **_out)
 349 {
 350         WERROR status;
 351         const struct dsdb_schema *schema;
 352         struct dsdb_extended_replicated_objects *out;
 353         struct ldb_result *ext_res;
 354         const struct drsuapi_DsReplicaObjectListItemEx *cur;
 355         uint32_t i;
 356         int ret;
 357
 358         schema = dsdb_get_schema(ldb);
 359         if (!schema) {
 360                 return WERR_DS_SCHEMA_NOT_LOADED;
 361         }
 362
 363         status = dsdb_verify_oid_mappings_drsuapi(schema, mapping_ctr);
 364         W_ERROR_NOT_OK_RETURN(status);
 365
 366         out = talloc_zero(mem_ctx, struct dsdb_extended_replicated_objects);
 367         W_ERROR_HAVE_NO_MEMORY(out);
 368         out->version            = DSDB_EXTENDED_REPLICATED_OBJECTS_VERSION;
 369
 370         out->partition_dn       = ldb_dn_new(out, ldb, partition_dn);
 371         W_ERROR_HAVE_NO_MEMORY(out->partition_dn);
 372
 373         out->source_dsa         = source_dsa;
 374         out->uptodateness_vector= uptodateness_vector;
 375
 376         out->num_objects        = object_count;
 377         out->objects            = talloc_array(out,
 378                                                struct dsdb_extended_replicated_object,
 379                                                out->num_objects);
 380         W_ERROR_HAVE_NO_MEMORY(out->objects);
 381
 382         for (i=0, cur = first_object; cur; cur = cur->next_object, i++) {
 383                 if (i == out->num_objects) {
 384                         return WERR_FOOBAR;
 385                 }
 386
 387                 status = dsdb_convert_object(ldb, schema, out, cur, gensec_skey, out->objects, &out->objects[i]);
 388                 W_ERROR_NOT_OK_RETURN(status);
 389         }
 390         if (i != out->num_objects) {
 391                 return WERR_FOOBAR;
 392         }
 393
 394         /* TODO: handle linked attributes */
 395
 396         ret = ldb_extended(ldb, DSDB_EXTENDED_REPLICATED_OBJECTS_OID, out, &ext_res);
 397         if (ret != LDB_SUCCESS) {
 398                 DEBUG(0,("Failed to apply records: %d: %s\n",
 399                         ret, ldb_strerror(ret)));
 400                 talloc_free(out);
 401                 return WERR_FOOBAR;
 402         }
 403         talloc_free(ext_res);
 404
 405         if (_out) {
 406                 *_out = out;
 407         } else {
 408                 talloc_free(out);
 409         }
 410
 411         return WERR_OK;
 412 }