Current File : //usr/lib/python3/dist-packages/samba/drs_utils.py
# DRS utility code
#
# Copyright Andrew Tridgell 2010
# Copyright Andrew Bartlett 2017
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
from samba.dcerpc import drsuapi, misc, drsblobs
from samba.net import Net
from samba.ndr import ndr_unpack
from samba import dsdb
from samba import werror
from samba import WERRORError
import samba
import ldb
from samba.dcerpc.drsuapi import (DRSUAPI_ATTID_name,
DRSUAPI_SUPPORTED_EXTENSION_GETCHGREQ_V8,
DRSUAPI_SUPPORTED_EXTENSION_GETCHGREQ_V10)
import re
class drsException(Exception):
"""Base element for drs errors"""
def __init__(self, value):
self.value = value
def __str__(self):
return "drsException: " + self.value
def drsuapi_connect(server, lp, creds, ip=None):
"""Make a DRSUAPI connection to the server.
:param server: the name of the server to connect to
:param lp: a samba line parameter object
:param creds: credential used for the connection
:param ip: Forced target server name
:return: A tuple with the drsuapi bind object, the drsuapi handle
and the supported extensions.
:raise drsException: if the connection fails
"""
binding_options = "seal"
if lp.log_level() >= 9:
binding_options += ",print"
# Allow forcing the IP
if ip is not None:
binding_options += f",target_hostname={server}"
binding_string = f"ncacn_ip_tcp:{ip}[{binding_options}]"
else:
binding_string = "ncacn_ip_tcp:%s[%s]" % (server, binding_options)
try:
drsuapiBind = drsuapi.drsuapi(binding_string, lp, creds)
(drsuapiHandle, bindSupportedExtensions) = drs_DsBind(drsuapiBind)
except Exception as e:
raise drsException("DRS connection to %s failed: %s" % (server, e))
return (drsuapiBind, drsuapiHandle, bindSupportedExtensions)
def sendDsReplicaSync(drsuapiBind, drsuapi_handle, source_dsa_guid,
naming_context, req_option):
"""Send DS replica sync request.
:param drsuapiBind: a drsuapi Bind object
:param drsuapi_handle: a drsuapi handle on the drsuapi connection
:param source_dsa_guid: the guid of the source dsa for the replication
:param naming_context: the DN of the naming context to replicate
:param req_options: replication options for the DsReplicaSync call
:raise drsException: if any error occur while sending and receiving the
reply for the dsReplicaSync
"""
nc = drsuapi.DsReplicaObjectIdentifier()
nc.dn = naming_context
req1 = drsuapi.DsReplicaSyncRequest1()
req1.naming_context = nc
req1.options = req_option
req1.source_dsa_guid = misc.GUID(source_dsa_guid)
try:
drsuapiBind.DsReplicaSync(drsuapi_handle, 1, req1)
except Exception as estr:
raise drsException("DsReplicaSync failed %s" % estr)
def drs_DsBind(drs):
'''make a DsBind call, returning the binding handle'''
bind_info = drsuapi.DsBindInfoCtr()
bind_info.length = 28
bind_info.info = drsuapi.DsBindInfo28()
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_BASE
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_ASYNC_REPLICATION
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_REMOVEAPI
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_MOVEREQ_V2
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHG_COMPRESS
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_DCINFO_V1
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_RESTORE_USN_OPTIMIZATION
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_KCC_EXECUTE
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_ADDENTRY_V2
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_LINKED_VALUE_REPLICATION
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_DCINFO_V2
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_INSTANCE_TYPE_NOT_REQ_ON_MOD
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_CRYPTO_BIND
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GET_REPL_INFO
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_STRONG_ENCRYPTION
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_DCINFO_V01
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_TRANSITIVE_MEMBERSHIP
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_ADD_SID_HISTORY
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_POST_BETA3
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GET_MEMBERSHIPS2
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHGREQ_V6
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_NONDOMAIN_NCS
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHGREQ_V8
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHGREPLY_V5
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHGREPLY_V6
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_ADDENTRYREPLY_V3
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_GETCHGREPLY_V7
bind_info.info.supported_extensions |= drsuapi.DRSUAPI_SUPPORTED_EXTENSION_VERIFY_OBJECT
(info, handle) = drs.DsBind(misc.GUID(drsuapi.DRSUAPI_DS_BIND_GUID), bind_info)
return (handle, info.info.supported_extensions)
def drs_get_rodc_partial_attribute_set(samdb):
'''get a list of attributes for RODC replication'''
partial_attribute_set = drsuapi.DsPartialAttributeSet()
partial_attribute_set.version = 1
attids = []
# the exact list of attids we send is quite critical. Note that
# we do ask for the secret attributes, but set SPECIAL_SECRET_PROCESSING
# to zero them out
schema_dn = samdb.get_schema_basedn()
res = samdb.search(base=schema_dn, scope=ldb.SCOPE_SUBTREE,
expression="objectClass=attributeSchema",
attrs=["lDAPDisplayName", "systemFlags",
"searchFlags"])
for r in res:
ldap_display_name = str(r["lDAPDisplayName"][0])
if "systemFlags" in r:
system_flags = r["systemFlags"][0]
if (int(system_flags) & (samba.dsdb.DS_FLAG_ATTR_NOT_REPLICATED |
samba.dsdb.DS_FLAG_ATTR_IS_CONSTRUCTED)):
continue
if "searchFlags" in r:
search_flags = r["searchFlags"][0]
if (int(search_flags) & samba.dsdb.SEARCH_FLAG_RODC_ATTRIBUTE):
continue
attid = samdb.get_attid_from_lDAPDisplayName(ldap_display_name)
attids.append(int(attid))
# the attids do need to be sorted, or windows doesn't return
# all the attributes we need
attids.sort()
partial_attribute_set.attids = attids
partial_attribute_set.num_attids = len(attids)
return partial_attribute_set
def drs_copy_highwater_mark(hwm, new_hwm):
"""
Copies the highwater mark by value, rather than by object reference. (This
avoids lingering talloc references to old GetNCChanges reply messages).
"""
hwm.tmp_highest_usn = new_hwm.tmp_highest_usn
hwm.reserved_usn = new_hwm.reserved_usn
hwm.highest_usn = new_hwm.highest_usn
class drs_Replicate(object):
'''DRS replication calls'''
def __init__(self, binding_string, lp, creds, samdb, invocation_id):
self.drs = drsuapi.drsuapi(binding_string, lp, creds)
(self.drs_handle, self.supports_ext) = drs_DsBind(self.drs)
self.net = Net(creds=creds, lp=lp)
self.samdb = samdb
if not isinstance(invocation_id, misc.GUID):
raise RuntimeError("Must supply GUID for invocation_id")
if invocation_id == misc.GUID("00000000-0000-0000-0000-000000000000"):
raise RuntimeError("Must not set GUID 00000000-0000-0000-0000-000000000000 as invocation_id")
self.replication_state = self.net.replicate_init(self.samdb, lp, self.drs, invocation_id)
self.more_flags = 0
def _should_retry_with_get_tgt(self, error_code, req):
# If the error indicates we fail to resolve a target object for a
# linked attribute, then we should retry the request with GET_TGT
# (if we support it and haven't already tried that)
supports_ext = self.supports_ext
return (error_code == werror.WERR_DS_DRA_RECYCLED_TARGET and
supports_ext & DRSUAPI_SUPPORTED_EXTENSION_GETCHGREQ_V10 and
(req.more_flags & drsuapi.DRSUAPI_DRS_GET_TGT) == 0)
@staticmethod
def _should_calculate_missing_anc_locally(error_code, req):
# If the error indicates we fail to resolve the parent object
# for a new object, then we assume we are replicating from a
# buggy server (Samba 4.5 and earlier) that doesn't really
# understand how to implement GET_ANC
return ((error_code == werror.WERR_DS_DRA_MISSING_PARENT) and
(req.replica_flags & drsuapi.DRSUAPI_DRS_GET_ANC) != 0)
def _calculate_missing_anc_locally(self, ctr):
self.guids_seen = set()
# walk objects in ctr, add to guid_seen as we see them
# note if an object doesn't have a parent
object_to_check = ctr.first_object
while True:
if object_to_check is None:
break
self.guids_seen.add(str(object_to_check.object.identifier.guid))
if object_to_check.parent_object_guid is not None \
and object_to_check.parent_object_guid \
!= misc.GUID("00000000-0000-0000-0000-000000000000") \
and str(object_to_check.parent_object_guid) not in self.guids_seen:
obj_dn = ldb.Dn(self.samdb, object_to_check.object.identifier.dn)
parent_dn = obj_dn.parent()
print(f"Object {parent_dn} with "
f"GUID {object_to_check.parent_object_guid} "
"was not sent by the server in this chunk")
object_to_check = object_to_check.next_object
def process_chunk(self, level, ctr, schema, req_level, req, first_chunk):
'''Processes a single chunk of received replication data'''
# pass the replication into the py_net.c python bindings for processing
self.net.replicate_chunk(self.replication_state, level, ctr,
schema=schema, req_level=req_level, req=req)
def replicate(self, dn, source_dsa_invocation_id, destination_dsa_guid,
schema=False, exop=drsuapi.DRSUAPI_EXOP_NONE, rodc=False,
replica_flags=None, full_sync=True, sync_forced=False, more_flags=0):
'''replicate a single DN'''
# setup for a GetNCChanges call
if self.supports_ext & DRSUAPI_SUPPORTED_EXTENSION_GETCHGREQ_V10:
req = drsuapi.DsGetNCChangesRequest10()
req.more_flags = (more_flags | self.more_flags)
req_level = 10
else:
req_level = 8
req = drsuapi.DsGetNCChangesRequest8()
req.destination_dsa_guid = destination_dsa_guid
req.source_dsa_invocation_id = source_dsa_invocation_id
req.naming_context = drsuapi.DsReplicaObjectIdentifier()
req.naming_context.dn = dn
# Default to a full replication if we don't find an upToDatenessVector
udv = None
hwm = drsuapi.DsReplicaHighWaterMark()
hwm.tmp_highest_usn = 0
hwm.reserved_usn = 0
hwm.highest_usn = 0
if not full_sync:
res = self.samdb.search(base=dn, scope=ldb.SCOPE_BASE,
attrs=["repsFrom"])
if "repsFrom" in res[0]:
for reps_from_packed in res[0]["repsFrom"]:
reps_from_obj = ndr_unpack(drsblobs.repsFromToBlob, reps_from_packed)
if reps_from_obj.ctr.source_dsa_invocation_id == source_dsa_invocation_id:
hwm = reps_from_obj.ctr.highwatermark
udv = drsuapi.DsReplicaCursorCtrEx()
udv.version = 1
udv.reserved1 = 0
udv.reserved2 = 0
cursors_v1 = []
cursors_v2 = dsdb._dsdb_load_udv_v2(self.samdb,
self.samdb.get_default_basedn())
for cursor_v2 in cursors_v2:
cursor_v1 = drsuapi.DsReplicaCursor()
cursor_v1.source_dsa_invocation_id = cursor_v2.source_dsa_invocation_id
cursor_v1.highest_usn = cursor_v2.highest_usn
cursors_v1.append(cursor_v1)
udv.cursors = cursors_v1
udv.count = len(cursors_v1)
req.highwatermark = hwm
req.uptodateness_vector = udv
if replica_flags is not None:
req.replica_flags = replica_flags
elif exop == drsuapi.DRSUAPI_EXOP_REPL_SECRET:
req.replica_flags = 0
else:
req.replica_flags = (drsuapi.DRSUAPI_DRS_INIT_SYNC |
drsuapi.DRSUAPI_DRS_PER_SYNC |
drsuapi.DRSUAPI_DRS_GET_ANC |
drsuapi.DRSUAPI_DRS_NEVER_SYNCED |
drsuapi.DRSUAPI_DRS_GET_ALL_GROUP_MEMBERSHIP)
if rodc:
req.replica_flags |= (
drsuapi.DRSUAPI_DRS_SPECIAL_SECRET_PROCESSING)
else:
req.replica_flags |= drsuapi.DRSUAPI_DRS_WRIT_REP
if sync_forced:
req.replica_flags |= drsuapi.DRSUAPI_DRS_SYNC_FORCED
req.max_object_count = 402
req.max_ndr_size = 402116
req.extended_op = exop
req.fsmo_info = 0
req.partial_attribute_set = None
req.partial_attribute_set_ex = None
req.mapping_ctr.num_mappings = 0
req.mapping_ctr.mappings = None
if not schema and rodc:
req.partial_attribute_set = drs_get_rodc_partial_attribute_set(self.samdb)
if not self.supports_ext & DRSUAPI_SUPPORTED_EXTENSION_GETCHGREQ_V8:
req_level = 5
req5 = drsuapi.DsGetNCChangesRequest5()
for a in dir(req5):
if a[0] != '_':
setattr(req5, a, getattr(req, a))
req = req5
num_objects = 0
num_links = 0
first_chunk = True
while True:
(level, ctr) = self.drs.DsGetNCChanges(self.drs_handle, req_level, req)
if ctr.first_object is None and ctr.object_count != 0:
raise RuntimeError("DsGetNCChanges: NULL first_object with object_count=%u" % (ctr.object_count))
try:
self.process_chunk(level, ctr, schema, req_level, req, first_chunk)
except WERRORError as e:
# Check if retrying with the GET_TGT flag set might resolve this error
if self._should_retry_with_get_tgt(e.args[0], req):
print("Missing target object - retrying with DRS_GET_TGT")
req.more_flags |= drsuapi.DRSUAPI_DRS_GET_TGT
# try sending the request again (this has the side-effect
# of causing the DC to restart the replication from scratch)
first_chunk = True
continue
if self._should_calculate_missing_anc_locally(e.args[0],
req):
print("Missing parent object - calculating missing objects locally")
self._calculate_missing_anc_locally(ctr)
raise e
first_chunk = False
num_objects += ctr.object_count
# Cope with servers that do not return level 6, so do not return any links
try:
num_links += ctr.linked_attributes_count
except AttributeError:
pass
if ctr.more_data == 0:
break
# update the request's HWM so we get the next chunk
drs_copy_highwater_mark(req.highwatermark, ctr.new_highwatermark)
return (num_objects, num_links)
# Handles the special case of creating a new clone of a DB, while also renaming
# the entire DB's objects on the way through
class drs_ReplicateRenamer(drs_Replicate):
'''Uses DRS replication to rename the entire DB'''
def __init__(self, binding_string, lp, creds, samdb, invocation_id,
old_base_dn, new_base_dn):
super(drs_ReplicateRenamer, self).__init__(binding_string, lp, creds,
samdb, invocation_id)
self.old_base_dn = old_base_dn
self.new_base_dn = new_base_dn
# because we're renaming the DNs, we know we're going to have trouble
# resolving link targets. Normally we'd get to the end of replication
# only to find we need to retry the whole replication with the GET_TGT
# flag set. Always setting the GET_TGT flag avoids this extra work.
self.more_flags = drsuapi.DRSUAPI_DRS_GET_TGT
def rename_dn(self, dn_str):
'''Uses string substitution to replace the base DN'''
return re.sub('%s$' % self.old_base_dn, self.new_base_dn, dn_str)
def update_name_attr(self, base_obj):
'''Updates the 'name' attribute for the base DN object'''
for attr in base_obj.attribute_ctr.attributes:
if attr.attid == DRSUAPI_ATTID_name:
base_dn = ldb.Dn(self.samdb, base_obj.identifier.dn)
new_name = base_dn.get_rdn_value()
attr.value_ctr.values[0].blob = new_name.encode('utf-16-le')
def rename_top_level_object(self, first_obj):
'''Renames the first/top-level object in a partition'''
old_dn = first_obj.identifier.dn
first_obj.identifier.dn = self.rename_dn(first_obj.identifier.dn)
print("Renaming partition %s --> %s" % (old_dn,
first_obj.identifier.dn))
# we also need to fix up the 'name' attribute for the base DN,
# otherwise the RDNs won't match
if first_obj.identifier.dn == self.new_base_dn:
self.update_name_attr(first_obj)
def process_chunk(self, level, ctr, schema, req_level, req, first_chunk):
'''Processes a single chunk of received replication data'''
# we need to rename the NC in every chunk - this gets used in searches
# when applying the chunk
if ctr.naming_context:
ctr.naming_context.dn = self.rename_dn(ctr.naming_context.dn)
# rename the first object in each partition. This will cause every
# subsequent object in the partition to be renamed as a side-effect
if first_chunk and ctr.object_count != 0:
self.rename_top_level_object(ctr.first_object.object)
# then do the normal repl processing to apply this chunk to our DB
super(drs_ReplicateRenamer, self).process_chunk(level, ctr, schema,
req_level, req,
first_chunk)
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