# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
+import uuid
import ldb
from ldb import LdbError
+from samba import werror
from samba.ndr import ndr_unpack
-from samba.dcerpc import misc
+from samba.dcerpc import misc, dnsp
+from samba.dcerpc.dnsp import DNS_TYPE_NS, DNS_TYPE_A, DNS_TYPE_AAAA, \
+ DNS_TYPE_CNAME, DNS_TYPE_SRV, DNS_TYPE_PTR
+
class DemoteException(Exception):
"""Base element for demote errors"""
return "DemoteException: " + self.value
-def remove_sysvol_references(samdb, rdn):
+def remove_sysvol_references(samdb, logger, dc_name):
+ # DNs under the Configuration DN:
realm = samdb.domain_dns_name()
- for s in ("CN=Enterprise,CN=Microsoft System Volumes,CN=System,CN=Configuration",
- "CN=%s,CN=Microsoft System Volumes,CN=System,CN=Configuration" % realm,
- "CN=Domain System Volumes (SYSVOL share),CN=File Replication Service,CN=System"):
+ for s in ("CN=Enterprise,CN=Microsoft System Volumes,CN=System",
+ "CN=%s,CN=Microsoft System Volumes,CN=System" % realm):
+ dn = ldb.Dn(samdb, s)
+
+ # This is verbose, but it is the safe, escape-proof way
+ # to add a base and add an arbitrary RDN.
+ if dn.add_base(samdb.get_config_basedn()) == False:
+ raise DemoteException("Failed constructing DN %s by adding base %s"
+ % (dn, samdb.get_config_basedn()))
+ if dn.add_child("CN=X") == False:
+ raise DemoteException("Failed constructing DN %s by adding child CN=X"
+ % (dn))
+ dn.set_component(0, "CN", dc_name)
try:
- samdb.delete(ldb.Dn(samdb,
- "%s,%s,%s" % (str(rdn), s, str(samdb.get_root_basedn()))))
- except ldb.LdbError, l:
- pass
+ logger.info("Removing Sysvol reference: %s" % dn)
+ samdb.delete(dn)
+ except ldb.LdbError as e:
+ (enum, estr) = e.args
+ if enum == ldb.ERR_NO_SUCH_OBJECT:
+ pass
+ else:
+ raise
+
+ # DNs under the Domain DN:
+ for s in ("CN=Domain System Volumes (SYSVOL share),CN=File Replication Service,CN=System",
+ "CN=Topology,CN=Domain System Volume,CN=DFSR-GlobalSettings,CN=System"):
+ # This is verbose, but it is the safe, escape-proof way
+ # to add a base and add an arbitrary RDN.
+ dn = ldb.Dn(samdb, s)
+ if dn.add_base(samdb.get_default_basedn()) == False:
+ raise DemoteException("Failed constructing DN %s by adding base %s"
+ % (dn, samdb.get_default_basedn()))
+ if dn.add_child("CN=X") == False:
+ raise DemoteException("Failed constructing DN %s by adding child "
+ "CN=X (soon to be CN=%s)" % (dn, dc_name))
+ dn.set_component(0, "CN", dc_name)
+
+ try:
+ logger.info("Removing Sysvol reference: %s" % dn)
+ samdb.delete(dn)
+ except ldb.LdbError as e1:
+ (enum, estr) = e1.args
+ if enum == ldb.ERR_NO_SUCH_OBJECT:
+ pass
+ else:
+ raise
+
-def remove_dns_references(samdb, dnsHostName):
+def remove_dns_references(samdb, logger, dnsHostName, ignore_no_name=False):
# Check we are using in-database DNS
zones = samdb.search(base="", scope=ldb.SCOPE_SUBTREE,
if len(zones) == 0:
return
+ dnsHostNameUpper = dnsHostName.upper()
+
try:
- rec = samdb.dns_lookup(dnsHostName)
- except RuntimeError as (enum, estr):
- if enum == 0x000025F2: #WERR_DNS_ERROR_NAME_DOES_NOT_EXIST
- return
+ (dn, primary_recs) = samdb.dns_lookup(dnsHostName)
+ except RuntimeError as e4:
+ (enum, estr) = e4.args
+ if (enum == werror.WERR_DNS_ERROR_NAME_DOES_NOT_EXIST or
+ enum == werror.WERR_DNS_ERROR_RCODE_NAME_ERROR):
+ if ignore_no_name:
+ remove_hanging_dns_references(samdb, logger,
+ dnsHostNameUpper,
+ zones)
+ return
raise DemoteException("lookup of %s failed: %s" % (dnsHostName, estr))
samdb.dns_replace(dnsHostName, [])
-def offline_remove_server(samdb, server_dn,
+ res = samdb.search("",
+ scope=ldb.SCOPE_BASE, attrs=["namingContexts"])
+ assert len(res) == 1
+ ncs = res[0]["namingContexts"]
+
+ # Work out the set of names we will likely have an A record on by
+ # default. This is by default all the partitions of type
+ # domainDNS. By finding the canocial name of all the partitions,
+ # we find the likely candidates. We only remove the record if it
+ # maches the IP that was used by the dnsHostName. This avoids us
+ # needing to look a the dns_update_list file from in the demote
+ # script.
+
+ def dns_name_from_dn(dn):
+ # The canonical string of DC=example,DC=com is
+ # example.com/
+ #
+ # The canonical string of CN=Configuration,DC=example,DC=com
+ # is example.com/Configuration
+ return ldb.Dn(samdb, dn).canonical_str().split('/', 1)[0]
+
+ # By using a set here, duplicates via (eg) example.com/Configuration
+ # do not matter, they become just example.com
+ a_names_to_remove_from \
+ = set(dns_name_from_dn(str(dn)) for dn in ncs)
+
+ def a_rec_to_remove(dnsRecord):
+ if dnsRecord.wType == DNS_TYPE_A or dnsRecord.wType == DNS_TYPE_AAAA:
+ for rec in primary_recs:
+ if rec.wType == dnsRecord.wType and rec.data == dnsRecord.data:
+ return True
+ return False
+
+ for a_name in a_names_to_remove_from:
+ try:
+ logger.debug("checking for DNS records to remove on %s" % a_name)
+ (a_rec_dn, a_recs) = samdb.dns_lookup(a_name)
+ except RuntimeError as e2:
+ (enum, estr) = e2.args
+ if enum == werror.WERR_DNS_ERROR_NAME_DOES_NOT_EXIST:
+ return
+ raise DemoteException("lookup of %s failed: %s" % (a_name, estr))
+
+ orig_num_recs = len(a_recs)
+ a_recs = [r for r in a_recs if not a_rec_to_remove(r)]
+
+ if len(a_recs) != orig_num_recs:
+ logger.info("updating %s keeping %d values, removing %s values" %
+ (a_name, len(a_recs), orig_num_recs - len(a_recs)))
+ samdb.dns_replace(a_name, a_recs)
+
+ remove_hanging_dns_references(samdb, logger, dnsHostNameUpper, zones)
+
+
+def remove_hanging_dns_references(samdb, logger, dnsHostNameUpper, zones):
+
+ # Find all the CNAME, NS, PTR and SRV records that point at the
+ # name we are removing
+
+ def to_remove(value):
+ dnsRecord = ndr_unpack(dnsp.DnssrvRpcRecord, value)
+ if dnsRecord.wType == DNS_TYPE_NS \
+ or dnsRecord.wType == DNS_TYPE_CNAME \
+ or dnsRecord.wType == DNS_TYPE_PTR:
+ if dnsRecord.data.upper() == dnsHostNameUpper:
+ return True
+ elif dnsRecord.wType == DNS_TYPE_SRV:
+ if dnsRecord.data.nameTarget.upper() == dnsHostNameUpper:
+ return True
+ return False
+
+ for zone in zones:
+ logger.debug("checking %s" % zone.dn)
+ records = samdb.search(base=zone.dn, scope=ldb.SCOPE_SUBTREE,
+ expression="(&(objectClass=dnsNode)"
+ "(!(dNSTombstoned=TRUE)))",
+ attrs=["dnsRecord"])
+ for record in records:
+ try:
+ orig_values = record["dnsRecord"]
+ except KeyError:
+ continue
+
+ # Remove references to dnsHostName in A, AAAA, NS, CNAME and SRV
+ values = [ndr_unpack(dnsp.DnssrvRpcRecord, v)
+ for v in orig_values if not to_remove(v)]
+
+ if len(values) != len(orig_values):
+ logger.info("updating %s keeping %d values, removing %s values"
+ % (record.dn, len(values),
+ len(orig_values) - len(values)))
+
+ # This requires the values to be unpacked, so this
+ # has been done in the list comprehension above
+ samdb.dns_replace_by_dn(record.dn, values)
+
+
+def offline_remove_server(samdb, logger,
+ server_dn,
remove_computer_obj=False,
remove_server_obj=False,
remove_sysvol_obj=False,
- remove_dns_names=False):
+ remove_dns_names=False,
+ remove_dns_account=False):
res = samdb.search("",
scope=ldb.SCOPE_BASE, attrs=["dsServiceName"])
assert len(res) == 1
scope=ldb.SCOPE_BASE,
expression="(objectClass=server)")
msg = msgs[0]
- dc_name = msgs[0]["cn"]
+ dc_name = str(msg["cn"][0])
try:
- computer_dn = ldb.Dn(samdb, msgs[0]["serverReference"][0])
+ computer_dn = ldb.Dn(samdb, msg["serverReference"][0].decode('utf8'))
except KeyError:
computer_dn = None
try:
- dnsHostName = msgs[0]["dnsHostName"][0]
+ dnsHostName = str(msg["dnsHostName"][0])
except KeyError:
dnsHostName = None
if remove_server_obj:
- # Remove the server DN
- samdb.delete(server_dn)
+ # Remove the server DN (do a tree-delete as it could still have a
+ # 'DNS Settings' child object if it's a Windows DC)
+ samdb.delete(server_dn, ["tree_delete:0"])
if computer_dn is not None:
computer_msgs = samdb.search(base=computer_dn,
expression="objectclass=computer",
attrs=["msDS-KrbTgtLink",
- "rIDSetReferences"],
+ "rIDSetReferences",
+ "cn"],
scope=ldb.SCOPE_BASE)
if "rIDSetReferences" in computer_msgs[0]:
- samdb.delete(computer_msgs[0]["rIDSetReferences"][0])
+ rid_set_dn = str(computer_msgs[0]["rIDSetReferences"][0])
+ logger.info("Removing RID Set: %s" % rid_set_dn)
+ samdb.delete(rid_set_dn)
if "msDS-KrbTgtLink" in computer_msgs[0]:
- samdb.delete(computer_msgs[0]["msDS-KrbTgtLink"][0])
+ krbtgt_link_dn = str(computer_msgs[0]["msDS-KrbTgtLink"][0])
+ logger.info("Removing RODC KDC account: %s" % krbtgt_link_dn)
+ samdb.delete(krbtgt_link_dn)
if remove_computer_obj:
# Delete the computer tree
+ logger.info("Removing computer account: %s (and any child objects)" % computer_dn)
samdb.delete(computer_dn, ["tree_delete:0"])
- if "dnsHostName" in msgs[0]:
- dnsHostName = msgs[0]["dnsHostName"][0]
+ if "dnsHostName" in msg:
+ dnsHostName = str(msg["dnsHostName"][0])
+
+ if remove_dns_account:
+ res = samdb.search(expression="(&(objectclass=user)(cn=dns-%s)(servicePrincipalName=DNS/%s))" %
+ (ldb.binary_encode(dc_name), dnsHostName),
+ attrs=[], scope=ldb.SCOPE_SUBTREE,
+ base=samdb.get_default_basedn())
+ if len(res) == 1:
+ logger.info("Removing Samba-specific DNS service account: %s" % res[0].dn)
+ samdb.delete(res[0].dn)
if dnsHostName is not None and remove_dns_names:
- remove_dns_references(samdb, dnsHostName)
+ remove_dns_references(samdb, logger, dnsHostName)
if remove_sysvol_obj:
- remove_sysvol_references(samdb, "CN=%s" % dc_name)
+ remove_sysvol_references(samdb, logger, dc_name)
+
-def offline_remove_ntds_dc(samdb, ntds_dn,
+def offline_remove_ntds_dc(samdb,
+ logger,
+ ntds_dn,
remove_computer_obj=False,
remove_server_obj=False,
remove_connection_obj=False,
seize_stale_fsmo=False,
remove_sysvol_obj=False,
- remove_dns_names=False):
+ remove_dns_names=False,
+ remove_dns_account=False):
res = samdb.search("",
scope=ldb.SCOPE_BASE, attrs=["dsServiceName"])
assert len(res) == 1
- my_serviceName = res[0]["dsServiceName"][0]
+ my_serviceName = ldb.Dn(samdb, res[0]["dsServiceName"][0].decode('utf8'))
server_dn = ntds_dn.parent()
+ if my_serviceName == ntds_dn:
+ raise DemoteException("Refusing to demote our own DSA: %s " % my_serviceName)
+
try:
msgs = samdb.search(base=ntds_dn, expression="objectClass=ntdsDSA",
- attrs=["objectGUID"], scope=ldb.SCOPE_BASE)
- except LdbError as (enum, estr):
+ attrs=["objectGUID"], scope=ldb.SCOPE_BASE)
+ except LdbError as e5:
+ (enum, estr) = e5.args
if enum == ldb.ERR_NO_SUCH_OBJECT:
- raise DemoteException("Given DN %s doesn't exist" % ntds_dn)
+ raise DemoteException("Given DN %s doesn't exist" % ntds_dn)
else:
raise
if (len(msgs) == 0):
expression="(&(objectclass=nTDSConnection)"
"(fromServer=<GUID=%s>))" % ntds_guid)
for conn in stale_connections:
+ logger.info("Removing nTDSConnection: %s" % conn.dn)
samdb.delete(conn.dn)
if seize_stale_fsmo:
m.dn = role.dn
m['value'] = ldb.MessageElement(val, ldb.FLAG_MOD_REPLACE,
'fsmoRoleOwner')
+ logger.warning("Seizing FSMO role on: %s (now owned by %s)"
+ % (role.dn, my_serviceName))
samdb.modify(m)
# Remove the NTDS setting tree
try:
+ logger.info("Removing nTDSDSA: %s (and any children)" % ntds_dn)
samdb.delete(ntds_dn, ["tree_delete:0"])
- except LdbError as (enum, estr):
+ except LdbError as e6:
+ (enum, estr) = e6.args
raise DemoteException("Failed to remove the DCs NTDS DSA object: %s"
% estr)
- offline_remove_server(samdb, server_dn,
+ offline_remove_server(samdb, logger, server_dn,
remove_computer_obj=remove_computer_obj,
remove_server_obj=remove_server_obj,
remove_sysvol_obj=remove_sysvol_obj,
- remove_dns_names=remove_dns_names)
+ remove_dns_names=remove_dns_names,
+ remove_dns_account=remove_dns_account)
-def remove_dc(samdb, dc_name):
+def remove_dc(samdb, logger, dc_name):
- # TODO: Check if this is the last server
+ # TODO: Check if this is the last server (covered mostly by
+ # refusing to remove our own name)
samdb.transaction_start()
- msgs = samdb.search(base=samdb.get_config_basedn(),
- attrs=["serverReference"],
- expression="(&(objectClass=server)(cn=%s))"
- % ldb.binary_encode(dc_name))
- if (len(msgs) == 0):
- raise DemoteException("%s is not an AD DC in %s"
- % (dc_name, samdb.domain_dns_name()))
- server_dn = msgs[0].dn
+ server_dn = None
- ntds_dn = ldb.Dn(samdb, "CN=NTDS Settings")
- ntds_dn.add_base(msgs[0].dn)
+ # Allow the name to be a the nTDS-DSA GUID
+ try:
+ ntds_guid = uuid.UUID(hex=dc_name)
+ ntds_dn = "<GUID=%s>" % ntds_guid
+ except ValueError:
+ try:
+ server_msgs = samdb.search(base=samdb.get_config_basedn(),
+ attrs=[],
+ expression="(&(objectClass=server)"
+ "(cn=%s))"
+ % ldb.binary_encode(dc_name))
+ except LdbError as e3:
+ (enum, estr) = e3.args
+ raise DemoteException("Failure checking if %s is an server "
+ "object in %s: %s"
+ % (dc_name, samdb.domain_dns_name(), estr))
+
+ if (len(server_msgs) == 0):
+ samdb.transaction_cancel()
+ raise DemoteException("%s is not an AD DC in %s"
+ % (dc_name, samdb.domain_dns_name()))
+ server_dn = server_msgs[0].dn
+
+ ntds_dn = ldb.Dn(samdb, "CN=NTDS Settings")
+ ntds_dn.add_base(server_dn)
+ pass
# Confirm this is really an ntdsDSA object
try:
- msgs = samdb.search(base=ntds_dn, attrs=[], scope=ldb.SCOPE_BASE,
- expression="(objectClass=ntdsdsa)")
- except LdbError as (enum, estr):
+ ntds_msgs = samdb.search(base=ntds_dn, attrs=[], scope=ldb.SCOPE_BASE,
+ expression="(objectClass=ntdsdsa)")
+ except LdbError as e7:
+ (enum, estr) = e7.args
if enum == ldb.ERR_NO_SUCH_OBJECT:
- offline_remove_server(samdb, msgs[0].dn,
- remove_computer_obj=True,
- remove_server_obj=True,
- remove_sysvol_obj=True,
- remove_dns_names=True)
-
- samdb.transaction_commit()
- return
- else:
+ ntds_msgs = []
pass
-
- offline_remove_ntds_dc(samdb, msgs[0].dn,
- remove_computer_obj=True,
- remove_server_obj=True,
- remove_connection_obj=True,
- seize_stale_fsmo=True,
- remove_sysvol_obj=True,
- remove_dns_names=True)
+ else:
+ samdb.transaction_cancel()
+ raise DemoteException(
+ "Failure checking if %s is an NTDS DSA in %s: %s" %
+ (ntds_dn, samdb.domain_dns_name(), estr))
+
+ # If the NTDS Settings child DN wasn't found or wasnt an ntdsDSA
+ # object, just remove the server object located above
+ if (len(ntds_msgs) == 0):
+ if server_dn is None:
+ samdb.transaction_cancel()
+ raise DemoteException("%s is not an AD DC in %s"
+ % (dc_name, samdb.domain_dns_name()))
+
+ offline_remove_server(samdb, logger,
+ server_dn,
+ remove_computer_obj=True,
+ remove_server_obj=True,
+ remove_sysvol_obj=True,
+ remove_dns_names=True,
+ remove_dns_account=True)
+ else:
+ offline_remove_ntds_dc(samdb, logger,
+ ntds_msgs[0].dn,
+ remove_computer_obj=True,
+ remove_server_obj=True,
+ remove_connection_obj=True,
+ seize_stale_fsmo=True,
+ remove_sysvol_obj=True,
+ remove_dns_names=True,
+ remove_dns_account=True)
samdb.transaction_commit()
-
def offline_remove_dc_RemoveDsServer(samdb, ntds_dn):
samdb.start_transaction()
- offline_remove_ntds_dc(samdb, ntds_dn)
+ offline_remove_ntds_dc(samdb, ntds_dn, None)
samdb.commit_transaction()