python/samba/drs_utils.py

   1 # DRS utility code
   2 #
   3 # Copyright Andrew Tridgell 2010
   4 # Copyright Andrew Bartlett 2017
   5 #
   6 # This program is free software; you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation; either version 3 of the License, or
   9 # (at your option) any later version.
  10 #
  11 # This program is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15 #
  16 # You should have received a copy of the GNU General Public License
  17 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 #
  19
  20 from samba.dcerpc import drsuapi, misc, drsblobs
  21 from samba.net import Net
  22 from samba.ndr import ndr_unpack
  23 from samba import dsdb
  24 from samba import werror
  25 from samba import WERRORError
  26 import samba, ldb
  27
  28
  29 class drsException(Exception):
  30     """Base element for drs errors"""
  31
  32     def __init__(self, value):
  33         self.value = value
  34
  35     def __str__(self):
  36         return "drsException: " + self.value
  37
  38
  39 def drsuapi_connect(server, lp, creds):
  40     """Make a DRSUAPI connection to the server.
  41
  42     :param server: the name of the server to connect to
  43     :param lp: a samba line parameter object
  44     :param creds: credential used for the connection
  45     :return: A tuple with the drsuapi bind object, the drsuapi handle
  46                 and the supported extensions.
  47     :raise drsException: if the connection fails
  48     """
  49
  50     binding_options = "seal"
  51     if lp.log_level() >= 9:
  52         binding_options += ",print"
  53     binding_string = "ncacn_ip_tcp:%s[%s]" % (server, binding_options)
  54     try:
  55         drsuapiBind = drsuapi.drsuapi(binding_string, lp, creds)
  56         (drsuapiHandle, bindSupportedExtensions) = drs_DsBind(drsuapiBind)
  57     except Exception as e:
  58         raise drsException("DRS connection to %s failed: %s" % (server, e))
  59
  60     return (drsuapiBind, drsuapiHandle, bindSupportedExtensions)
  61
  62
  63 def sendDsReplicaSync(drsuapiBind, drsuapi_handle, source_dsa_guid,
  64         naming_context, req_option):
  65     """Send DS replica sync request.
  66
  67     :param drsuapiBind: a drsuapi Bind object
  68     :param drsuapi_handle: a drsuapi handle on the drsuapi connection
  69     :param source_dsa_guid: the guid of the source dsa for the replication
  70     :param naming_context: the DN of the naming context to replicate
  71     :param req_options: replication options for the DsReplicaSync call
  72     :raise drsException: if any error occur while sending and receiving the
  73         reply for the dsReplicaSync
  74     """
  75
  76     nc = drsuapi.DsReplicaObjectIdentifier()
  77     nc.dn = naming_context
  78
  79     req1 = drsuapi.DsReplicaSyncRequest1()
  80     req1.naming_context = nc;
  81     req1.options = req_option
  82     req1.source_dsa_guid = misc.GUID(source_dsa_guid)
  83
  84     try:
  85         drsuapiBind.DsReplicaSync(drsuapi_handle, 1, req1)
  86     except Exception as estr:
  87         raise drsException("DsReplicaSync failed %s" % estr)
  88
  89
  90 def sendRemoveDsServer(drsuapiBind, drsuapi_handle, server_dsa_dn, domain):
  91     """Send RemoveDSServer request.
  92
  93     :param drsuapiBind: a drsuapi Bind object
  94     :param drsuapi_handle: a drsuapi handle on the drsuapi connection
  95     :param server_dsa_dn: a DN object of the server's dsa that we want to
  96         demote
  97     :param domain: a DN object of the server's domain
  98     :raise drsException: if any error occur while sending and receiving the
  99         reply for the DsRemoveDSServer
 100     """
 101
 102     try:
 103         req1 = drsuapi.DsRemoveDSServerRequest1()
 104         req1.server_dn = str(server_dsa_dn)
 105         req1.domain_dn = str(domain)
 106         req1.commit = 1
 107
 108         drsuapiBind.DsRemoveDSServer(drsuapi_handle, 1, req1)
 109     except Exception as estr:
 110         raise drsException("DsRemoveDSServer failed %s" % estr)
 111
 112
 113 def drs_DsBind(drs):
 114     '''make a DsBind call, returning the binding handle'''
 115     bind_info = drsuapi.DsBindInfoCtr()
 116     bind_info.length = 28
 117     bind_info.info = drsuapi.DsBindInfo28()
 118     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_BASE
 119     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_ASYNC_REPLICATION
 120     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_REMOVEAPI
 121     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_MOVEREQ_V2
 122     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHG_COMPRESS
 123     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_DCINFO_V1
 124     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_RESTORE_USN_OPTIMIZATION
 125     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_KCC_EXECUTE
 126     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_ADDENTRY_V2
 127     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_LINKED_VALUE_REPLICATION
 128     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_DCINFO_V2
 129     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_INSTANCE_TYPE_NOT_REQ_ON_MOD
 130     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_CRYPTO_BIND
 131     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GET_REPL_INFO
 132     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_STRONG_ENCRYPTION
 133     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_DCINFO_V01
 134     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_TRANSITIVE_MEMBERSHIP
 135     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_ADD_SID_HISTORY
 136     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_POST_BETA3
 137     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GET_MEMBERSHIPS2
 138     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHGREQ_V6
 139     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_NONDOMAIN_NCS
 140     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHGREQ_V8
 141     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHGREPLY_V5
 142     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHGREPLY_V6
 143     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_ADDENTRYREPLY_V3
 144     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHGREPLY_V7
 145     bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_VERIFY_OBJECT
 146     (info, handle) = drs.DsBind(misc.GUID(drsuapi.DRSUAPI_DS_BIND_GUID), bind_info)
 147
 148     return (handle, info.info.supported_extensions)
 149
 150
 151 def drs_get_rodc_partial_attribute_set(samdb):
 152     '''get a list of attributes for RODC replication'''
 153     partial_attribute_set = drsuapi.DsPartialAttributeSet()
 154     partial_attribute_set.version = 1
 155
 156     attids = []
 157
 158     # the exact list of attids we send is quite critical. Note that
 159     # we do ask for the secret attributes, but set SPECIAL_SECRET_PROCESSING
 160     # to zero them out
 161     schema_dn = samdb.get_schema_basedn()
 162     res = samdb.search(base=schema_dn, scope=ldb.SCOPE_SUBTREE,
 163                        expression="objectClass=attributeSchema",
 164                        attrs=["lDAPDisplayName", "systemFlags",
 165                               "searchFlags"])
 166
 167     for r in res:
 168         ldap_display_name = r["lDAPDisplayName"][0]
 169         if "systemFlags" in r:
 170             system_flags      = r["systemFlags"][0]
 171             if (int(system_flags) & (samba.dsdb.DS_FLAG_ATTR_NOT_REPLICATED |
 172                                      samba.dsdb.DS_FLAG_ATTR_IS_CONSTRUCTED)):
 173                 continue
 174         if "searchFlags" in r:
 175             search_flags = r["searchFlags"][0]
 176             if (int(search_flags) & samba.dsdb.SEARCH_FLAG_RODC_ATTRIBUTE):
 177                 continue
 178         attid = samdb.get_attid_from_lDAPDisplayName(ldap_display_name)
 179         attids.append(int(attid))
 180
 181     # the attids do need to be sorted, or windows doesn't return
 182     # all the attributes we need
 183     attids.sort()
 184     partial_attribute_set.attids         = attids
 185     partial_attribute_set.num_attids = len(attids)
 186     return partial_attribute_set
 187
 188
 189 class drs_Replicate(object):
 190     '''DRS replication calls'''
 191
 192     def __init__(self, binding_string, lp, creds, samdb, invocation_id):
 193         self.drs = drsuapi.drsuapi(binding_string, lp, creds)
 194         (self.drs_handle, self.supported_extensions) = drs_DsBind(self.drs)
 195         self.net = Net(creds=creds, lp=lp)
 196         self.samdb = samdb
 197         if not isinstance(invocation_id, misc.GUID):
 198             raise RuntimeError("Must supply GUID for invocation_id")
 199         if invocation_id == misc.GUID("00000000-0000-0000-0000-000000000000"):
 200             raise RuntimeError("Must not set GUID 00000000-0000-0000-0000-000000000000 as invocation_id")
 201         self.replication_state = self.net.replicate_init(self.samdb, lp, self.drs, invocation_id)
 202
 203     def _should_retry_with_get_tgt(self, error_code, req):
 204
 205         # If the error indicates we fail to resolve a target object for a
 206         # linked attribute, then we should retry the request with GET_TGT
 207         # (if we support it and haven't already tried that)
 208
 209         # TODO fix up the below line when we next update werror_err_table.txt
 210         # and pull in the new error-code
 211         # return (error_code == werror.WERR_DS_DRA_RECYCLED_TARGET and
 212         return (error_code == 0x21bf and
 213                 (req.more_flags & drsuapi.DRSUAPI_DRS_GET_TGT) == 0 and
 214                 self.supported_extensions & drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHGREQ_V10)
 215
 216     def replicate(self, dn, source_dsa_invocation_id, destination_dsa_guid,
 217                   schema=False, exop=drsuapi.DRSUAPI_EXOP_NONE, rodc=False,
 218                   replica_flags=None, full_sync=True, sync_forced=False, more_flags=0):
 219         '''replicate a single DN'''
 220
 221         # setup for a GetNCChanges call
 222         if self.supported_extensions & drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHGREQ_V10:
 223             req = drsuapi.DsGetNCChangesRequest10()
 224             req.more_flags = more_flags
 225             req_level = 10
 226         else:
 227             req_level = 8
 228             req = drsuapi.DsGetNCChangesRequest8()
 229
 230         req.destination_dsa_guid = destination_dsa_guid
 231         req.source_dsa_invocation_id = source_dsa_invocation_id
 232         req.naming_context = drsuapi.DsReplicaObjectIdentifier()
 233         req.naming_context.dn = dn
 234
 235         # Default to a full replication if we don't find an upToDatenessVector
 236         udv = None
 237         hwm = drsuapi.DsReplicaHighWaterMark()
 238         hwm.tmp_highest_usn = 0
 239         hwm.reserved_usn = 0
 240         hwm.highest_usn = 0
 241
 242         if not full_sync:
 243             res = self.samdb.search(base=dn, scope=ldb.SCOPE_BASE,
 244                                     attrs=["repsFrom"])
 245             if "repsFrom" in res[0]:
 246                 for reps_from_packed in res[0]["repsFrom"]:
 247                     reps_from_obj = ndr_unpack(drsblobs.repsFromToBlob, reps_from_packed)
 248                     if reps_from_obj.ctr.source_dsa_invocation_id == source_dsa_invocation_id:
 249                         hwm = reps_from_obj.ctr.highwatermark
 250
 251             udv = drsuapi.DsReplicaCursorCtrEx()
 252             udv.version = 1
 253             udv.reserved1 = 0
 254             udv.reserved2 = 0
 255
 256             cursors_v1 = []
 257             cursors_v2 = dsdb._dsdb_load_udv_v2(self.samdb,
 258                                                 self.samdb.get_default_basedn())
 259             for cursor_v2 in cursors_v2:
 260                 cursor_v1 = drsuapi.DsReplicaCursor()
 261                 cursor_v1.source_dsa_invocation_id = cursor_v2.source_dsa_invocation_id
 262                 cursor_v1.highest_usn = cursor_v2.highest_usn
 263                 cursors_v1.append(cursor_v1)
 264
 265             udv.cursors = cursors_v1
 266             udv.count = len(cursors_v1)
 267
 268         req.highwatermark = hwm
 269         req.uptodateness_vector = udv
 270
 271         if replica_flags is not None:
 272             req.replica_flags = replica_flags
 273         elif exop == drsuapi.DRSUAPI_EXOP_REPL_SECRET:
 274             req.replica_flags = 0
 275         else:
 276             req.replica_flags = (drsuapi.DRSUAPI_DRS_INIT_SYNC |
 277                                  drsuapi.DRSUAPI_DRS_PER_SYNC |
 278                                  drsuapi.DRSUAPI_DRS_GET_ANC |
 279                                  drsuapi.DRSUAPI_DRS_NEVER_SYNCED |
 280                                  drsuapi.DRSUAPI_DRS_GET_ALL_GROUP_MEMBERSHIP)
 281             if rodc:
 282                 req.replica_flags |= (
 283                      drsuapi.DRSUAPI_DRS_SPECIAL_SECRET_PROCESSING)
 284             else:
 285                 req.replica_flags |= drsuapi.DRSUAPI_DRS_WRIT_REP
 286
 287         if sync_forced:
 288             req.replica_flags |= drsuapi.DRSUAPI_DRS_SYNC_FORCED
 289
 290         req.max_object_count = 402
 291         req.max_ndr_size = 402116
 292         req.extended_op = exop
 293         req.fsmo_info = 0
 294         req.partial_attribute_set = None
 295         req.partial_attribute_set_ex = None
 296         req.mapping_ctr.num_mappings = 0
 297         req.mapping_ctr.mappings = None
 298
 299         if not schema and rodc:
 300             req.partial_attribute_set = drs_get_rodc_partial_attribute_set(self.samdb)
 301
 302         if not self.supported_extensions & drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHGREQ_V8:
 303             req_level = 5
 304             req5 = drsuapi.DsGetNCChangesRequest5()
 305             for a in dir(req5):
 306                 if a[0] != '_':
 307                     setattr(req5, a, getattr(req, a))
 308             req = req5
 309
 310         num_objects = 0
 311         num_links = 0
 312         while True:
 313             (level, ctr) = self.drs.DsGetNCChanges(self.drs_handle, req_level, req)
 314             if ctr.first_object is None and ctr.object_count != 0:
 315                 raise RuntimeError("DsGetNCChanges: NULL first_object with object_count=%u" % (ctr.object_count))
 316
 317             try:
 318                 self.net.replicate_chunk(self.replication_state, level, ctr,
 319                     schema=schema, req_level=req_level, req=req)
 320             except WERRORError as e:
 321                 # Check if retrying with the GET_TGT flag set might resolve this error
 322                 if self._should_retry_with_get_tgt(e.args[0], req):
 323
 324                     print("Missing target object - retrying with DRS_GET_TGT")
 325                     req.more_flags |= drsuapi.DRSUAPI_DRS_GET_TGT
 326
 327                     # try sending the request again
 328                     continue
 329                 else:
 330                     raise e
 331
 332             num_objects += ctr.object_count
 333
 334             # Cope with servers that do not return level 6, so do not return any links
 335             try:
 336                 num_links += ctr.linked_attributes_count
 337             except AttributeError:
 338                 pass
 339
 340             if ctr.more_data == 0:
 341                 break
 342             req.highwatermark = ctr.new_highwatermark
 343
 344         return (num_objects, num_links)