source4/scripting/python/samba/dbchecker.py

   1 #!/usr/bin/env python
   2 #
   3 # Samba4 AD database checker
   4 #
   5 # Copyright (C) Andrew Tridgell 2011
   6 #
   7 # This program is free software; you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation; either version 3 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # This program is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 #
  20
  21 import ldb
  22 from samba import dsdb
  23 from samba import common
  24 from samba.dcerpc import misc
  25
  26
  27 class dsdb_DN(object):
  28     '''a class to manipulate DN components'''
  29
  30     def __init__(self, samdb, dnstring, syntax_oid):
  31         if syntax_oid in [ dsdb.DSDB_SYNTAX_BINARY_DN, dsdb.DSDB_SYNTAX_STRING_DN ]:
  32             colons = dnstring.split(':')
  33             if len(colons) < 4:
  34                 raise Exception("invalid DN prefix")
  35             prefix_len = 4 + len(colons[1]) + int(colons[1])
  36             self.prefix = dnstring[0:prefix_len]
  37             self.dnstring = dnstring[prefix_len:]
  38         else:
  39             self.dnstring = dnstring
  40             self.prefix = ''
  41         try:
  42             self.dn = ldb.Dn(samdb, self.dnstring)
  43         except Exception, msg:
  44             print("ERROR: bad DN string '%s'" % self.dnstring)
  45             raise
  46
  47     def __str__(self):
  48         return self.prefix + str(self.dn.extended_str(mode=1))
  49
  50 class dbcheck(object):
  51     """check a SAM database for errors"""
  52
  53     def __init__(self, samdb, samdb_schema=None, verbose=False, fix=False, yes=False, quiet=False):
  54         self.samdb = samdb
  55         self.samdb_schema = (samdb_schema or samdb)
  56         self.verbose = verbose
  57         self.fix = fix
  58         self.yes = yes
  59         self.quiet = quiet
  60
  61     def check_database(self, DN=None, scope=ldb.SCOPE_SUBTREE, controls=[], attrs=['*']):
  62         '''perform a database check, returning the number of errors found'''
  63
  64         res = self.samdb.search(base=DN, scope=scope, attrs=['dn'], controls=controls)
  65         self.report('Checking %u objects' % len(res))
  66         error_count = 0
  67         for object in res:
  68             error_count += self.check_object(object.dn, attrs=attrs)
  69         if error_count != 0 and not self.fix:
  70             self.report("Please use --fix to fix these errors")
  71         self.report('Checked %u objects (%u errors)' % (len(res), error_count))
  72
  73         return error_count
  74
  75
  76     def report(self, msg):
  77         '''print a message unless quiet is set'''
  78         if not self.quiet:
  79             print(msg)
  80
  81
  82     ################################################################
  83     # a local confirm function that obeys the --fix and --yes options
  84     def confirm(self, msg):
  85         '''confirm a change'''
  86         if not self.fix:
  87             return False
  88         if self.quiet:
  89             return self.yes
  90         return common.confirm(msg, forced=self.yes)
  91
  92
  93     ################################################################
  94     # handle empty attributes
  95     def err_empty_attribute(self, dn, attrname):
  96         '''fix empty attributes'''
  97         self.report("ERROR: Empty attribute %s in %s" % (attrname, dn))
  98         if not self.confirm('Remove empty attribute %s from %s?' % (attrname, dn)):
  99             self.report("Not fixing empty attribute %s" % attrname)
 100             return
 101
 102         m = ldb.Message()
 103         m.dn = dn
 104         m[attrname] = ldb.MessageElement('', ldb.FLAG_MOD_DELETE, attrname)
 105         if self.verbose:
 106             self.report(self.samdb.write_ldif(m, ldb.CHANGETYPE_MODIFY))
 107         try:
 108             self.samdb.modify(m, controls=["relax:0"], validate=False)
 109         except Exception, msg:
 110             self.report("Failed to remove empty attribute %s : %s" % (attrname, msg))
 111             return
 112         self.report("Removed empty attribute %s" % attrname)
 113
 114
 115     ################################################################
 116     # handle normalisation mismatches
 117     def err_normalise_mismatch(self, dn, attrname, values):
 118         '''fix attribute normalisation errors'''
 119         self.report("ERROR: Normalisation error for attribute %s in %s" % (attrname, dn))
 120         mod_list = []
 121         for val in values:
 122             normalised = self.samdb.dsdb_normalise_attributes(self.samdb_schema, attrname, [val])
 123             if len(normalised) != 1:
 124                 self.report("Unable to normalise value '%s'" % val)
 125                 mod_list.append((val, ''))
 126             elif (normalised[0] != val):
 127                 self.report("value '%s' should be '%s'" % (val, normalised[0]))
 128                 mod_list.append((val, normalised[0]))
 129         if not self.confirm('Fix normalisation for %s from %s?' % (attrname, dn)):
 130             self.report("Not fixing attribute %s" % attrname)
 131             return
 132
 133         m = ldb.Message()
 134         m.dn = dn
 135         for i in range(0, len(mod_list)):
 136             (val, nval) = mod_list[i]
 137             m['value_%u' % i] = ldb.MessageElement(val, ldb.FLAG_MOD_DELETE, attrname)
 138             if nval != '':
 139                 m['normv_%u' % i] = ldb.MessageElement(nval, ldb.FLAG_MOD_ADD, attrname)
 140
 141         if self.verbose:
 142             self.report(self.samdb.write_ldif(m, ldb.CHANGETYPE_MODIFY))
 143         try:
 144             self.samdb.modify(m, controls=["relax:0"], validate=False)
 145         except Exception, msg:
 146             self.report("Failed to normalise attribute %s : %s" % (attrname, msg))
 147             return
 148         self.report("Normalised attribute %s" % attrname)
 149
 150     def is_deleted_objects_dn(self, dsdb_dn):
 151         '''see if a dsdb_DN is the special Deleted Objects DN'''
 152         return dsdb_dn.prefix == "B:32:18E2EA80684F11D2B9AA00C04F79F805:"
 153
 154
 155     ################################################################
 156     # handle a missing GUID extended DN component
 157     def err_incorrect_dn_GUID(self, dn, attrname, val, dsdb_dn, errstr):
 158         self.report("ERROR: %s component for %s in object %s - %s" % (errstr, attrname, dn, val))
 159         controls=["extended_dn:1:1"]
 160         if self.is_deleted_objects_dn(dsdb_dn):
 161             controls.append("show_deleted:1")
 162         try:
 163             res = self.samdb.search(base=str(dsdb_dn.dn), scope=ldb.SCOPE_BASE,
 164                                     attrs=[], controls=controls)
 165         except ldb.LdbError, (enum, estr):
 166             self.report("unable to find object for DN %s - cannot fix (%s)" % (dsdb_dn.dn, estr))
 167             return
 168         dsdb_dn.dn = res[0].dn
 169
 170         if not self.confirm('Change DN to %s?' % str(dsdb_dn)):
 171             self.report("Not fixing %s" % errstr)
 172             return
 173         m = ldb.Message()
 174         m.dn = dn
 175         m['old_value'] = ldb.MessageElement(val, ldb.FLAG_MOD_DELETE, attrname)
 176         m['new_value'] = ldb.MessageElement(str(dsdb_dn), ldb.FLAG_MOD_ADD, attrname)
 177         if self.verbose:
 178             self.report(self.samdb.write_ldif(m, ldb.CHANGETYPE_MODIFY))
 179         try:
 180             self.samdb.modify(m)
 181         except Exception, msg:
 182             self.report("Failed to fix %s on attribute %s : %s" % (errstr, attrname, msg))
 183             return
 184         self.report("Fixed %s on attribute %s" % (errstr, attrname))
 185
 186
 187     ################################################################
 188     # handle a DN pointing to a deleted object
 189     def err_deleted_dn(self, dn, attrname, val, dsdb_dn, correct_dn):
 190         self.report("ERROR: target DN is deleted for %s in object %s - %s" % (attrname, dn, val))
 191         self.report("Target GUID points at deleted DN %s" % correct_dn)
 192         if not self.confirm('Remove DN?'):
 193             self.report("Not removing")
 194             return
 195         m = ldb.Message()
 196         m.dn = dn
 197         m['old_value'] = ldb.MessageElement(val, ldb.FLAG_MOD_DELETE, attrname)
 198         if self.verbose:
 199             self.report(self.samdb.write_ldif(m, ldb.CHANGETYPE_MODIFY))
 200         try:
 201             self.samdb.modify(m)
 202         except Exception, msg:
 203             self.report("Failed to remove deleted DN attribute %s : %s" % (attrname, msg))
 204             return
 205         self.report("Removed deleted DN on attribute %s" % attrname)
 206
 207
 208     ################################################################
 209     # handle a DN string being incorrect
 210     def err_dn_target_mismatch(self, dn, attrname, val, dsdb_dn, correct_dn):
 211         self.report("ERROR: incorrect DN string component for %s in object %s - %s" % (attrname, dn, val))
 212         dsdb_dn.dn = correct_dn
 213
 214         if not self.confirm('Change DN to %s?' % str(dsdb_dn)):
 215             self.report("Not fixing %s" % errstr)
 216             return
 217         m = ldb.Message()
 218         m.dn = dn
 219         m['old_value'] = ldb.MessageElement(val, ldb.FLAG_MOD_DELETE, attrname)
 220         m['new_value'] = ldb.MessageElement(str(dsdb_dn), ldb.FLAG_MOD_ADD, attrname)
 221         if self.verbose:
 222             self.report(self.samdb.write_ldif(m, ldb.CHANGETYPE_MODIFY))
 223         try:
 224             self.samdb.modify(m)
 225         except Exception, msg:
 226             self.report("Failed to fix incorrect DN string on attribute %s : %s" % (attrname, msg))
 227             return
 228         self.report("Fixed incorrect DN string on attribute %s" % (attrname))
 229
 230
 231     ################################################################
 232     # specialised checking for a dn attribute
 233     def check_dn(self, obj, attrname, syntax_oid):
 234         '''check a DN attribute for correctness'''
 235         error_count = 0
 236         for val in obj[attrname]:
 237             dsdb_dn = dsdb_DN(self.samdb, val, syntax_oid)
 238
 239             # all DNs should have a GUID component
 240             guid = dsdb_dn.dn.get_extended_component("GUID")
 241             if guid is None:
 242                 error_count += 1
 243                 self.err_incorrect_dn_GUID(obj.dn, attrname, val, dsdb_dn, "missing GUID")
 244                 continue
 245
 246             guidstr = str(misc.GUID(guid))
 247
 248             # check its the right GUID
 249             try:
 250                 res = self.samdb.search(base="<GUID=%s>" % guidstr, scope=ldb.SCOPE_BASE,
 251                                         attrs=['isDeleted'], controls=["extended_dn:1:1", "show_deleted:1"])
 252             except ldb.LdbError, (enum, estr):
 253                 error_count += 1
 254                 self.err_incorrect_dn_GUID(obj.dn, attrname, val, dsdb_dn, "incorrect GUID")
 255                 continue
 256
 257             # the target DN might be deleted
 258             if ((not self.is_deleted_objects_dn(dsdb_dn)) and
 259                 'isDeleted' in res[0] and
 260                 res[0]['isDeleted'][0].upper() == "TRUE"):
 261                 # note that we don't check this for the special wellKnownObjects prefix
 262                 # for Deleted Objects, as we expect that to be deleted
 263                 error_count += 1
 264                 self.err_deleted_dn(obj.dn, attrname, val, dsdb_dn, res[0].dn)
 265                 continue
 266
 267             # check the DN matches in string form
 268             if res[0].dn.extended_str() != dsdb_dn.dn.extended_str():
 269                 error_count += 1
 270                 self.err_dn_target_mismatch(obj.dn, attrname, val, dsdb_dn, res[0].dn)
 271                 continue
 272
 273         return error_count
 274
 275
 276
 277     ################################################################
 278     # check one object - calls to individual error handlers above
 279     def check_object(self, dn, attrs=['*']):
 280         '''check one object'''
 281         if self.verbose:
 282             self.report("Checking object %s" % dn)
 283         res = self.samdb.search(base=dn, scope=ldb.SCOPE_BASE, controls=["extended_dn:1:1"], attrs=attrs)
 284         if len(res) != 1:
 285             self.report("Object %s disappeared during check" % dn)
 286             return 1
 287         obj = res[0]
 288         error_count = 0
 289         for attrname in obj:
 290             if attrname == 'dn':
 291                 continue
 292
 293             # check for empty attributes
 294             for val in obj[attrname]:
 295                 if val == '':
 296                     self.err_empty_attribute(dn, attrname)
 297                     error_count += 1
 298                     continue
 299
 300             # get the syntax oid for the attribute, so we can can have
 301             # special handling for some specific attribute types
 302             syntax_oid = self.samdb_schema.get_syntax_oid_from_lDAPDisplayName(attrname)
 303
 304             if syntax_oid in [ dsdb.DSDB_SYNTAX_BINARY_DN, dsdb.DSDB_SYNTAX_OR_NAME,
 305                                dsdb.DSDB_SYNTAX_STRING_DN, ldb.LDB_SYNTAX_DN ]:
 306                 # it's some form of DN, do specialised checking on those
 307                 error_count += self.check_dn(obj, attrname, syntax_oid)
 308
 309             # check for incorrectly normalised attributes
 310             for val in obj[attrname]:
 311                 normalised = self.samdb.dsdb_normalise_attributes(self.samdb_schema, attrname, [val])
 312                 if len(normalised) != 1 or normalised[0] != val:
 313                     self.err_normalise_mismatch(dn, attrname, obj[attrname])
 314                     error_count += 1
 315                     break
 316         return error_count