s4-samba-tool: added dbcheck commmand

this will be used as a consistency checker and repair tool for
sam.ldb. This initial checkin just checks for empty attributes and
offers to fix them

Autobuild-User: Andrew Tridgell <tridge@samba.org>
Autobuild-Date: Fri Jun 10 10:31:56 CEST 2011 on sn-devel-104

source4/scripting/python/samba/netcmd/__init__.py

@@ -212,3 +212,5 @@ from samba.netcmd.ldapcmp import cmd_ldapcmp
 commands["ldapcmp"] = cmd_ldapcmp()
 from samba.netcmd.testparm import cmd_testparm
 commands["testparm"] =  cmd_testparm()
+from samba.netcmd.dbcheck import cmd_dbcheck
+commands["dbcheck"] =  cmd_dbcheck()

source4/scripting/python/samba/netcmd/dbcheck.py

@@ -0,0 +1,123 @@
+#!/usr/bin/env python
+#
+# Samba4 AD database checker
+#
+# Copyright (C) Andrew Tridgell 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 <http://www.gnu.org/licenses/>.
+#
+
+import samba, ldb
+import samba.getopt as options
+from samba.auth import system_session
+from samba.samdb import SamDB
+from samba.dcerpc import security
+from samba.netcmd import (
+    Command,
+    CommandError,
+    Option
+    )
+
+def confirm(self, msg):
+    '''confirm an action with the user'''
+    if self.yes:
+        print("%s [YES]" % msg)
+        return True
+    v = raw_input(msg + ' [y/N] ')
+    return v.upper() in ['Y', 'YES']
+
+
+def empty_attribute(self, dn, attrname):
+    '''fix empty attributes'''
+    print("ERROR: Empty attribute %s in %s" % (attrname, dn))
+    if not self.fix:
+        return
+    if not confirm(self, 'Remove empty attribute %s from %s?' % (attrname, dn)):
+        print("Not fixing empty attribute %s" % attrname)
+        return
+
+    m = ldb.Message()
+    m.dn = dn
+    m[attrname] = ldb.MessageElement('', ldb.FLAG_MOD_DELETE, attrname)
+    try:
+        self.samdb.modify(m, ["relax:0"])
+    except Exception, msg:
+        print("Failed to remove empty attribute %s : %s" % (attrname, msg))
+        return
+    print("Removed empty attribute %s" % attrname)
+
+
+
+def check_object(self, dn):
+    '''check one object'''
+    if self.verbose:
+        print("Checking object %s" % dn)
+    res = self.samdb.search(base=dn, scope=ldb.SCOPE_BASE)
+    if len(res) != 1:
+        print("Object %s disappeared during check" % dn)
+        return
+    obj = res[0]
+    for attrname in obj:
+        if attrname == 'dn':
+            continue
+        for val in obj[attrname]:
+            if val == '':
+                empty_attribute(self, dn, attrname)
+                continue
+
+
+class cmd_dbcheck(Command):
+    """check local AD database for errors"""
+    synopsis = "dbcheck <DN> [options]"
+
+    takes_optiongroups = {
+        "sambaopts": options.SambaOptions,
+        "versionopts": options.VersionOptions,
+        "credopts": options.CredentialsOptionsDouble,
+    }
+
+    takes_args = ["DN?"]
+
+    takes_options = [
+        Option("--scope", dest="scope", default="SUB",
+            help="Pass search scope that builds DN list. Options: SUB, ONE, BASE"),
+        Option("--fix", dest="fix", default=False, action='store_true',
+               help='Fix any errors found'),
+        Option("--yes", dest="yes", default=False, action='store_true',
+               help="don't confirm changes, just do them all"),
+        Option("-v", "--verbose", dest="verbose", action="store_true", default=False,
+            help="Print more details of checking"),
+        ]
+
+    def run(self, DN=None, verbose=False, fix=False, yes=False,
+            scope="SUB", credopts=None, sambaopts=None, versionopts=None):
+        self.lp = sambaopts.get_loadparm()
+        self.creds = credopts.get_credentials(self.lp, fallback_machine=True)
+
+        self.samdb = SamDB(session_info=system_session(), url=None,
+                           credentials=self.creds, lp=self.lp)
+        self.verbose = verbose
+        self.fix = fix
+        self.yes = yes
+
+        scope_map = { "SUB": ldb.SCOPE_SUBTREE, "BASE":ldb.SCOPE_BASE, "ONE":ldb.SCOPE_ONELEVEL }
+        scope = scope.upper()
+        if not scope in scope_map:
+            raise CommandError("Unknown scope %s" % scope)
+        self.search_scope = scope_map[scope]
+
+        res = self.samdb.search(base=DN, scope=self.search_scope, attrs=['dn'])
+        for object in res:
+            check_object(self, object.dn)
+        print('Checked %u objects' % len(res))