PEP8: add spaces after operators
[nivanova/samba-autobuild/.git] / python / samba / remove_dc.py
index 41b9621e2780048dd5b539e9dc9983a4949993dc..3dc93741a45d0d29d9d26605ba7ae901a358d735 100644 (file)
 # 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"""
@@ -31,7 +36,7 @@ class DemoteException(Exception):
         return "DemoteException: " + self.value
 
 
-def remove_sysvol_references(samdb, dc_name):
+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",
@@ -41,15 +46,17 @@ def remove_sysvol_references(samdb, dc_name):
         # 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" \
+            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))
+            raise DemoteException("Failed constructing DN %s by adding child CN=X"
+                                  % (dn))
         dn.set_component(0, "CN", dc_name)
         try:
+            logger.info("Removing Sysvol reference: %s" % dn)
             samdb.delete(dn)
-        except ldb.LdbError as (enum, estr):
+        except ldb.LdbError as e:
+            (enum, estr) = e.args
             if enum == ldb.ERR_NO_SUCH_OBJECT:
                 pass
             else:
@@ -62,22 +69,25 @@ def remove_sysvol_references(samdb, dc_name):
         # 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" % \
+            raise DemoteException("Failed constructing DN %s by adding base" %
                                   (dn, samdb.get_default_basedn()))
         if dn.add_child("CN=X") == False:
-            raise DemoteException("Failed constructing DN %s by adding child %s"\
-                                  % (dn, rdn))
+            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 (enum, estr):
+        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,
@@ -87,19 +97,126 @@ def remove_dns_references(samdb, dnsHostName):
     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(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
@@ -115,7 +232,7 @@ def offline_remove_server(samdb, server_dn,
     dc_name = str(msgs[0]["cn"][0])
 
     try:
-        computer_dn = ldb.Dn(samdb, msgs[0]["serverReference"][0])
+        computer_dn = ldb.Dn(samdb, msgs[0]["serverReference"][0].decode('utf8'))
     except KeyError:
         computer_dn = None
 
@@ -125,44 +242,64 @@ def offline_remove_server(samdb, server_dn,
         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 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, 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 = ldb.Dn(samdb, 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:
@@ -170,10 +307,11 @@ def offline_remove_ntds_dc(samdb, ntds_dn,
 
     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):
@@ -196,6 +334,7 @@ def offline_remove_ntds_dc(samdb, ntds_dn,
                                          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:
@@ -211,74 +350,110 @@ def offline_remove_ntds_dc(samdb, ntds_dn,
             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 (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: "
+                                  % (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: "
+                                  % (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()