#!/usr/bin/env python # # Samba4 AD database checker # # Copyright (C) Andrew Tridgell 2011 # Copyright (C) Matthieu Patou 2011 # # 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 . # import ldb from samba import dsdb from samba import common from samba.dcerpc import misc from samba.ndr import ndr_unpack from samba.dcerpc import drsblobs from samba.common import dsdb_Dn class dbcheck(object): """check a SAM database for errors""" def __init__(self, samdb, samdb_schema=None, verbose=False, fix=False, yes=False, quiet=False, in_transaction=False): self.samdb = samdb self.dict_oid_name = None self.samdb_schema = (samdb_schema or samdb) self.verbose = verbose self.fix = fix self.yes = yes self.quiet = quiet self.remove_all_unknown_attributes = False self.remove_all_empty_attributes = False self.fix_all_normalisation = False self.fix_all_DN_GUIDs = False self.remove_all_deleted_DN_links = False self.fix_all_target_mismatch = False self.fix_all_metadata = False self.fix_time_metadata = False self.fix_all_missing_backlinks = False self.fix_all_orphaned_backlinks = False self.in_transaction = in_transaction def check_database(self, DN=None, scope=ldb.SCOPE_SUBTREE, controls=[], attrs=['*']): '''perform a database check, returning the number of errors found''' res = self.samdb.search(base=DN, scope=scope, attrs=['dn'], controls=controls) self.report('Checking %u objects' % len(res)) error_count = 0 for object in res: error_count += self.check_object(object.dn, attrs=attrs) if DN is None: error_count += self.check_rootdse() if error_count != 0 and not self.fix: self.report("Please use --fix to fix these errors") self.report('Checked %u objects (%u errors)' % (len(res), error_count)) return error_count def report(self, msg): '''print a message unless quiet is set''' if not self.quiet: print(msg) ################################################################ # a local confirm function that obeys the --fix and --yes options def confirm(self, msg, allow_all=False, forced=False): '''confirm a change''' if not self.fix: return False if self.quiet: return self.yes if self.yes: forced = True return common.confirm(msg, forced=forced, allow_all=allow_all) ################################################################ # a local confirm function with support for 'all' def confirm_all(self, msg, all_attr): '''confirm a change with support for "all" ''' if not self.fix: return False if self.quiet: return self.yes if getattr(self, all_attr) == 'NONE': return False if getattr(self, all_attr) == 'ALL': forced = True else: forced = self.yes c = common.confirm(msg, forced=forced, allow_all=True) if c == 'ALL': setattr(self, all_attr, 'ALL') return True if c == 'NONE': setattr(self, all_attr, 'NONE') return True return c def do_modify(self, m, controls, msg, validate=True): '''perform a modify with optional verbose output''' if self.verbose: self.report(self.samdb.write_ldif(m, ldb.CHANGETYPE_MODIFY)) try: self.samdb.modify(m, controls=controls, validate=validate) except Exception, err: self.report("%s : %s" % (msg, err)) return False return True ################################################################ # handle empty attributes def err_empty_attribute(self, dn, attrname): '''fix empty attributes''' self.report("ERROR: Empty attribute %s in %s" % (attrname, dn)) if not self.confirm_all('Remove empty attribute %s from %s?' % (attrname, dn), 'remove_all_empty_attributes'): self.report("Not fixing empty attribute %s" % attrname) return m = ldb.Message() m.dn = dn m[attrname] = ldb.MessageElement('', ldb.FLAG_MOD_DELETE, attrname) if self.do_modify(m, ["relax:0", "show_recycled:1"], "Failed to remove empty attribute %s" % attrname, validate=False): self.report("Removed empty attribute %s" % attrname) ################################################################ # handle normalisation mismatches def err_normalise_mismatch(self, dn, attrname, values): '''fix attribute normalisation errors''' self.report("ERROR: Normalisation error for attribute %s in %s" % (attrname, dn)) mod_list = [] for val in values: normalised = self.samdb.dsdb_normalise_attributes(self.samdb_schema, attrname, [val]) if len(normalised) != 1: self.report("Unable to normalise value '%s'" % val) mod_list.append((val, '')) elif (normalised[0] != val): self.report("value '%s' should be '%s'" % (val, normalised[0])) mod_list.append((val, normalised[0])) if not self.confirm_all('Fix normalisation for %s from %s?' % (attrname, dn), 'fix_all_normalisation'): self.report("Not fixing attribute %s" % attrname) return m = ldb.Message() m.dn = dn for i in range(0, len(mod_list)): (val, nval) = mod_list[i] m['value_%u' % i] = ldb.MessageElement(val, ldb.FLAG_MOD_DELETE, attrname) if nval != '': m['normv_%u' % i] = ldb.MessageElement(nval, ldb.FLAG_MOD_ADD, attrname) if self.do_modify(m, ["relax:0", "show_recycled:1"], "Failed to normalise attribute %s" % attrname, validate=False): self.report("Normalised attribute %s" % attrname) def is_deleted_objects_dn(self, dsdb_dn): '''see if a dsdb_Dn is the special Deleted Objects DN''' return dsdb_dn.prefix == "B:32:18E2EA80684F11D2B9AA00C04F79F805:" ################################################################ # handle a DN pointing to a deleted object def err_deleted_dn(self, dn, attrname, val, dsdb_dn, correct_dn): self.report("ERROR: target DN is deleted for %s in object %s - %s" % (attrname, dn, val)) self.report("Target GUID points at deleted DN %s" % correct_dn) if not self.confirm_all('Remove DN link?', 'remove_all_deleted_DN_links'): self.report("Not removing") return m = ldb.Message() m.dn = dn m['old_value'] = ldb.MessageElement(val, ldb.FLAG_MOD_DELETE, attrname) if self.do_modify(m, ["show_recycled:1", "local_oid:%s:0" % dsdb.DSDB_CONTROL_DBCHECK], "Failed to remove deleted DN attribute %s" % attrname): self.report("Removed deleted DN on attribute %s" % attrname) ################################################################ # handle a missing target DN (both GUID and DN string form are missing) def err_missing_dn_GUID(self, dn, attrname, val, dsdb_dn): # check if its a backlink linkID = self.samdb_schema.get_linkId_from_lDAPDisplayName(attrname) if (linkID & 1 == 0) and str(dsdb_dn).find('DEL\\0A') == -1: self.report("Not removing dangling forward link") return self.err_deleted_dn(dn, attrname, val, dsdb_dn, dsdb_dn) ################################################################ # handle a missing GUID extended DN component def err_incorrect_dn_GUID(self, dn, attrname, val, dsdb_dn, errstr): self.report("ERROR: %s component for %s in object %s - %s" % (errstr, attrname, dn, val)) controls=["extended_dn:1:1", "show_recycled:1"] try: res = self.samdb.search(base=str(dsdb_dn.dn), scope=ldb.SCOPE_BASE, attrs=[], controls=controls) except ldb.LdbError, (enum, estr): self.report("unable to find object for DN %s - (%s)" % (dsdb_dn.dn, estr)) self.err_missing_dn_GUID(dn, attrname, val, dsdb_dn) return if len(res) == 0: self.report("unable to find object for DN %s" % dsdb_dn.dn) self.err_missing_dn_GUID(dn, attrname, val, dsdb_dn) return dsdb_dn.dn = res[0].dn if not self.confirm_all('Change DN to %s?' % str(dsdb_dn), 'fix_all_DN_GUIDs'): self.report("Not fixing %s" % errstr) return m = ldb.Message() m.dn = dn m['old_value'] = ldb.MessageElement(val, ldb.FLAG_MOD_DELETE, attrname) m['new_value'] = ldb.MessageElement(str(dsdb_dn), ldb.FLAG_MOD_ADD, attrname) if self.do_modify(m, ["show_recycled:1"], "Failed to fix %s on attribute %s" % (errstr, attrname)): self.report("Fixed %s on attribute %s" % (errstr, attrname)) ################################################################ # handle a DN string being incorrect def err_dn_target_mismatch(self, dn, attrname, val, dsdb_dn, correct_dn, errstr): self.report("ERROR: incorrect DN string component for %s in object %s - %s" % (attrname, dn, val)) dsdb_dn.dn = correct_dn if not self.confirm_all('Change DN to %s?' % str(dsdb_dn), 'fix_all_target_mismatch'): self.report("Not fixing %s" % errstr) return m = ldb.Message() m.dn = dn m['old_value'] = ldb.MessageElement(val, ldb.FLAG_MOD_DELETE, attrname) m['new_value'] = ldb.MessageElement(str(dsdb_dn), ldb.FLAG_MOD_ADD, attrname) if self.do_modify(m, ["show_recycled:1"], "Failed to fix incorrect DN string on attribute %s" % attrname): self.report("Fixed incorrect DN string on attribute %s" % (attrname)) ################################################################ # handle an unknown attribute error def err_unknown_attribute(self, obj, attrname): '''handle an unknown attribute error''' self.report("ERROR: unknown attribute '%s' in %s" % (attrname, obj.dn)) if not self.confirm_all('Remove unknown attribute %s' % attrname, 'remove_all_unknown_attributes'): self.report("Not removing %s" % attrname) return m = ldb.Message() m.dn = obj.dn m['old_value'] = ldb.MessageElement([], ldb.FLAG_MOD_DELETE, attrname) if self.do_modify(m, ["relax:0", "show_recycled:1"], "Failed to remove unknown attribute %s" % attrname): self.report("Removed unknown attribute %s" % (attrname)) ################################################################ # handle a missing backlink def err_missing_backlink(self, obj, attrname, val, backlink_name, target_dn): '''handle a missing backlink value''' self.report("ERROR: missing backlink attribute '%s' in %s for link %s in %s" % (backlink_name, target_dn, attrname, obj.dn)) if not self.confirm_all('Fix missing backlink %s' % backlink_name, 'fix_all_missing_backlinks'): self.report("Not fixing missing backlink %s" % backlink_name) return m = ldb.Message() m.dn = obj.dn m['old_value'] = ldb.MessageElement(val, ldb.FLAG_MOD_DELETE, attrname) m['new_value'] = ldb.MessageElement(val, ldb.FLAG_MOD_ADD, attrname) if self.do_modify(m, ["show_recycled:1"], "Failed to fix missing backlink %s" % backlink_name): self.report("Fixed missing backlink %s" % (backlink_name)) ################################################################ # handle a orphaned backlink def err_orphaned_backlink(self, obj, attrname, val, link_name, target_dn): '''handle a orphaned backlink value''' self.report("ERROR: orphaned backlink attribute '%s' in %s for link %s in %s" % (attrname, obj.dn, link_name, target_dn)) if not self.confirm_all('Remove orphaned backlink %s' % link_name, 'fix_all_orphaned_backlinks'): self.report("Not removing orphaned backlink %s" % link_name) return m = ldb.Message() m.dn = obj.dn m['value'] = ldb.MessageElement(val, ldb.FLAG_MOD_DELETE, attrname) if self.do_modify(m, ["show_recycled:1", "relax:0"], "Failed to fix orphaned backlink %s" % link_name): self.report("Fixed orphaned backlink %s" % (link_name)) ################################################################ # specialised checking for a dn attribute def check_dn(self, obj, attrname, syntax_oid): '''check a DN attribute for correctness''' error_count = 0 for val in obj[attrname]: dsdb_dn = dsdb_Dn(self.samdb, val, syntax_oid) # all DNs should have a GUID component guid = dsdb_dn.dn.get_extended_component("GUID") if guid is None: error_count += 1 self.err_incorrect_dn_GUID(obj.dn, attrname, val, dsdb_dn, "missing GUID") continue guidstr = str(misc.GUID(guid)) attrs=['isDeleted'] linkID = self.samdb_schema.get_linkId_from_lDAPDisplayName(attrname) reverse_link_name = self.samdb_schema.get_backlink_from_lDAPDisplayName(attrname) if reverse_link_name is not None: attrs.append(reverse_link_name) # check its the right GUID try: res = self.samdb.search(base="" % guidstr, scope=ldb.SCOPE_BASE, attrs=attrs, controls=["extended_dn:1:1", "show_recycled:1"]) except ldb.LdbError, (enum, estr): error_count += 1 self.err_incorrect_dn_GUID(obj.dn, attrname, val, dsdb_dn, "incorrect GUID") continue # now we have two cases - the source object might or might not be deleted is_deleted = 'isDeleted' in obj and obj['isDeleted'][0].upper() == 'TRUE' target_is_deleted = 'isDeleted' in res[0] and res[0]['isDeleted'][0].upper() == 'TRUE' # the target DN is not allowed to be deleted, unless the target DN is the # special Deleted Objects container if target_is_deleted and not is_deleted and not self.is_deleted_objects_dn(dsdb_dn): error_count += 1 self.err_deleted_dn(obj.dn, attrname, val, dsdb_dn, res[0].dn) continue # check the DN matches in string form if res[0].dn.extended_str() != dsdb_dn.dn.extended_str(): error_count += 1 self.err_dn_target_mismatch(obj.dn, attrname, val, dsdb_dn, res[0].dn, "incorrect string version of DN") continue # check the reverse_link is correct if there should be one if reverse_link_name is not None: match_count = 0 if reverse_link_name in res[0]: for v in res[0][reverse_link_name]: if v == obj.dn.extended_str(): match_count += 1 if match_count != 1: error_count += 1 if linkID & 1: self.err_orphaned_backlink(obj, attrname, val, reverse_link_name, dsdb_dn.dn) else: self.err_missing_backlink(obj, attrname, val, reverse_link_name, dsdb_dn.dn) continue return error_count def get_originating_time(self, val, attid): '''Read metadata properties and return the originating time for a given attributeId. :return: the originating time or 0 if not found ''' repl = ndr_unpack(drsblobs.replPropertyMetaDataBlob, str(val)) obj = repl.ctr for o in repl.ctr.array: if o.attid == attid: return o.originating_change_time return 0 def process_metadata(self, val): '''Read metadata properties and list attributes in it''' list_att = [] repl = ndr_unpack(drsblobs.replPropertyMetaDataBlob, str(val)) obj = repl.ctr for o in repl.ctr.array: att = self.samdb_schema.get_lDAPDisplayName_by_attid(o.attid) list_att.append(att.lower()) return list_att def fix_metadata(self, dn, attr): '''re-write replPropertyMetaData elements for a single attribute for a object. This is used to fix missing replPropertyMetaData elements''' res = self.samdb.search(base = dn, scope=ldb.SCOPE_BASE, attrs = [attr], controls = ["search_options:1:2", "show_recycled:1"]) msg = res[0] nmsg = ldb.Message() nmsg.dn = dn nmsg[attr] = ldb.MessageElement(msg[attr], ldb.FLAG_MOD_REPLACE, attr) if self.do_modify(nmsg, ["relax:0", "provision:0", "show_recycled:1"], "Failed to fix metadata for attribute %s" % attr): self.report("Fixed metadata for attribute %s" % attr) ################################################################ # check one object - calls to individual error handlers above def check_object(self, dn, attrs=['*']): '''check one object''' if self.verbose: self.report("Checking object %s" % dn) if '*' in attrs: attrs.append("replPropertyMetaData") try: res = self.samdb.search(base=dn, scope=ldb.SCOPE_BASE, controls=["extended_dn:1:1", "show_recycled:1", "show_deleted:1"], attrs=attrs) except ldb.LdbError, (enum, estr): if enum == ldb.ERR_NO_SUCH_OBJECT: if self.in_transaction: self.report("ERROR: Object %s disappeared during check" % dn) return 1 return 0 raise if len(res) != 1: self.report("ERROR: Object %s failed to load during check" % dn) return 1 obj = res[0] error_count = 0 list_attrs_from_md = [] list_attrs_seen = [] got_repl_property_meta_data = False for attrname in obj: if attrname == 'dn': continue if str(attrname).lower() == 'replpropertymetadata': list_attrs_from_md = self.process_metadata(obj[attrname]) got_repl_property_meta_data = True continue # check for empty attributes for val in obj[attrname]: if val == '': self.err_empty_attribute(dn, attrname) error_count += 1 continue # get the syntax oid for the attribute, so we can can have # special handling for some specific attribute types try: syntax_oid = self.samdb_schema.get_syntax_oid_from_lDAPDisplayName(attrname) except Exception, msg: self.err_unknown_attribute(obj, attrname) error_count += 1 continue flag = self.samdb_schema.get_systemFlags_from_lDAPDisplayName(attrname) if (not flag & dsdb.DS_FLAG_ATTR_NOT_REPLICATED and not flag & dsdb.DS_FLAG_ATTR_IS_CONSTRUCTED and not self.samdb_schema.get_linkId_from_lDAPDisplayName(attrname)): list_attrs_seen.append(str(attrname).lower()) if syntax_oid in [ dsdb.DSDB_SYNTAX_BINARY_DN, dsdb.DSDB_SYNTAX_OR_NAME, dsdb.DSDB_SYNTAX_STRING_DN, ldb.SYNTAX_DN ]: # it's some form of DN, do specialised checking on those error_count += self.check_dn(obj, attrname, syntax_oid) # check for incorrectly normalised attributes for val in obj[attrname]: normalised = self.samdb.dsdb_normalise_attributes(self.samdb_schema, attrname, [val]) if len(normalised) != 1 or normalised[0] != val: self.err_normalise_mismatch(dn, attrname, obj[attrname]) error_count += 1 break show_dn = True if got_repl_property_meta_data: rdn = (str(dn).split(","))[0] if rdn == "CN=Deleted Objects": isDeletedAttId = 131120 # It's 29/12/9999 at 23:59:59 UTC as specified in MS-ADTS 7.1.1.4.2 Deleted Objects Container expectedTimeDo = 2650466015990000000 originating = self.get_originating_time(obj["replPropertyMetaData"], isDeletedAttId) if originating != expectedTimeDo: if self.confirm_all("Fix isDeleted originating_change_time on '%s'" % str(dn), 'fix_time_metadata'): nmsg = ldb.Message() nmsg.dn = dn nmsg["isDeleted"] = ldb.MessageElement("TRUE", ldb.FLAG_MOD_REPLACE, "isDeleted") error_count += 1 self.samdb.modify(nmsg, controls=["provision:0"]) else: self.report("Not fixing isDeleted originating_change_time on '%s'" % str(dn)) for att in list_attrs_seen: if not att in list_attrs_from_md: if show_dn: self.report("On object %s" % dn) show_dn = False error_count += 1 self.report("ERROR: Attribute %s not present in replication metadata" % att) if not self.confirm_all("Fix missing replPropertyMetaData element '%s'" % att, 'fix_all_metadata'): self.report("Not fixing missing replPropertyMetaData element '%s'" % att) continue self.fix_metadata(dn, att) return error_count ################################################################ # check special @ROOTDSE attributes def check_rootdse(self): '''check the @ROOTDSE special object''' dn = ldb.Dn(self.samdb, '@ROOTDSE') if self.verbose: self.report("Checking object %s" % dn) res = self.samdb.search(base=dn, scope=ldb.SCOPE_BASE) if len(res) != 1: self.report("Object %s disappeared during check" % dn) return 1 obj = res[0] error_count = 0 # check that the dsServiceName is in GUID form if not 'dsServiceName' in obj: self.report('ERROR: dsServiceName missing in @ROOTDSE') return error_count+1 if not obj['dsServiceName'][0].startswith('" % guid_str, ldb.FLAG_MOD_REPLACE, 'dsServiceName') if self.do_modify(m, [], "Failed to change dsServiceName to GUID form", validate=False): self.report("Changed dsServiceName to GUID form") return error_count ############################################### # re-index the database def reindex_database(self): '''re-index the whole database''' m = ldb.Message() m.dn = ldb.Dn(self.samdb, "@ATTRIBUTES") m['add'] = ldb.MessageElement('NONE', ldb.FLAG_MOD_ADD, 'force_reindex') m['delete'] = ldb.MessageElement('NONE', ldb.FLAG_MOD_DELETE, 'force_reindex') return self.do_modify(m, [], 're-indexed database', validate=False)