Adding upstream version 2:4.20.0+dfsg.upstream/2%4.20.0+dfsg

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 456 insertions, 0 deletions

diff --git a/python/samba/drs_utils.py b/python/samba/drs_utils.py
new file mode 100644
index 0000000..06e6928
--- /dev/null
+++ b/python/samba/drs_utils.py
@@ -0,0 +1,456 @@
+# 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().__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().process_chunk(level, ctr, schema, req_level, req, first_chunk)