path: root/source4/scripting/bin/samba_upgradeprovision

#!/usr/bin/env python
# vim: expandtab
#
# Copyright (C) Matthieu Patou <mat@matws.net> 2009 - 2010
#
# Based on provision a Samba4 server by
# Copyright (C) Jelmer Vernooij <jelmer@samba.org> 2007-2008
# Copyright (C) Andrew Bartlett <abartlet@samba.org> 2008
#
#
# 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 logging
import optparse
import os
import shutil
import sys
import tempfile
import re
import traceback
# Allow to run from s4 source directory (without installing samba)
sys.path.insert(0, "bin/python")

import ldb
import samba
import samba.getopt as options

from base64 import b64encode
from samba.credentials import DONT_USE_KERBEROS
from samba.auth import system_session, admin_session
from ldb import (SCOPE_SUBTREE, SCOPE_BASE,
                FLAG_MOD_REPLACE, FLAG_MOD_ADD, FLAG_MOD_DELETE,
                MessageElement, Message, Dn, LdbError)
from samba import param, dsdb, Ldb
from samba.common import confirm
from samba.provision import (get_domain_descriptor, find_provision_key_parameters,
                            get_config_descriptor,
                            ProvisioningError, get_last_provision_usn,
                            get_max_usn, update_provision_usn, setup_path)
from samba.schema import get_linked_attributes, Schema, get_schema_descriptor
from samba.dcerpc import security, drsblobs
from samba.ndr import ndr_unpack
from samba.upgradehelpers import (dn_sort, get_paths, newprovision,
                                 get_ldbs, findprovisionrange,
                                 usn_in_range, identic_rename, get_diff_sddls,
                                 update_secrets, CHANGE, ERROR, SIMPLE,
                                 CHANGEALL, GUESS, CHANGESD, PROVISION,
                                 updateOEMInfo, getOEMInfo, update_gpo,
                                 delta_update_basesamdb, update_policyids,
                                 update_machine_account_password,
                                 search_constructed_attrs_stored,
                                 int64range2str, update_dns_account_password,
                                 increment_calculated_keyversion_number,
                                 print_provision_ranges)
from samba.xattr import copytree_with_xattrs

# make sure the script dies immediately when hitting control-C,
# rather than raising KeyboardInterrupt. As we do all database
# operations using transactions, this is safe.
import signal
signal.signal(signal.SIGINT, signal.SIG_DFL)

replace=2**FLAG_MOD_REPLACE
add=2**FLAG_MOD_ADD
delete=2**FLAG_MOD_DELETE
never=0


# Will be modified during provision to tell if default sd has been modified
# somehow ...

#Errors are always logged

__docformat__ = "restructuredText"

# Attributes that are never copied from the reference provision (even if they
# do not exist in the destination object).
# This is most probably because they are populated automatcally when object is
# created
# This also apply to imported object from reference provision
replAttrNotCopied = [   "dn", "whenCreated", "whenChanged", "objectGUID",
                        "parentGUID", "objectCategory", "distinguishedName",
                        "instanceType", "cn",
                        "lmPwdHistory", "pwdLastSet", "ntPwdHistory",
                        "unicodePwd", "dBCSPwd", "supplementalCredentials",
                        "gPCUserExtensionNames", "gPCMachineExtensionNames",
                        "maxPwdAge", "secret", "possibleInferiors", "privilege",
                        "sAMAccountType", "oEMInformation", "creationTime" ]

nonreplAttrNotCopied = ["uSNCreated", "replPropertyMetaData", "uSNChanged",
                        "nextRid" ,"rIDNextRID", "rIDPreviousAllocationPool"]

nonDSDBAttrNotCopied = ["msDS-KeyVersionNumber", "priorSecret", "priorWhenChanged"]


attrNotCopied = replAttrNotCopied
attrNotCopied.extend(nonreplAttrNotCopied)
attrNotCopied.extend(nonDSDBAttrNotCopied)
# Usually for an object that already exists we do not overwrite attributes as
# they might have been changed for good reasons. Anyway for a few of them it's
# mandatory to replace them otherwise the provision will be broken somehow.
# But for attribute that are just missing we do not have to specify them as the default
# behavior is to add missing attribute
hashOverwrittenAtt = {  "prefixMap": replace, "systemMayContain": replace,
                        "systemOnly":replace, "searchFlags":replace,
                        "mayContain":replace, "systemFlags":replace+add,
                        "description":replace, "operatingSystemVersion":replace,
                        "adminPropertyPages":replace, "groupType":replace,
                        "wellKnownObjects":replace, "privilege":never,
                        "defaultSecurityDescriptor": replace,
                        "rIDAvailablePool": never,
                        "versionNumber" : add,
                        "rIDNextRID": add, "rIDUsedPool": never,
                        "defaultSecurityDescriptor": replace + add,
                        "isMemberOfPartialAttributeSet": delete,
                        "attributeDisplayNames": replace + add,
                        "versionNumber": add}

dnNotToRecalculate = []
dnToRecalculate = []
backlinked = []
forwardlinked = set()
dn_syntax_att = []
not_replicated = []
def define_what_to_log(opts):
    what = 0
    if opts.debugchange:
        what = what | CHANGE
    if opts.debugchangesd:
        what = what | CHANGESD
    if opts.debugguess:
        what = what | GUESS
    if opts.debugprovision:
        what = what | PROVISION
    if opts.debugall:
        what = what | CHANGEALL
    return what


parser = optparse.OptionParser("provision [options]")
sambaopts = options.SambaOptions(parser)
parser.add_option_group(sambaopts)
parser.add_option_group(options.VersionOptions(parser))
credopts = options.CredentialsOptions(parser)
parser.add_option_group(credopts)
parser.add_option("--setupdir", type="string", metavar="DIR",
                  help="directory with setup files")
parser.add_option("--debugprovision", help="Debug provision", action="store_true")
parser.add_option("--debugguess", action="store_true",
                  help="Print information on which values are guessed")
parser.add_option("--debugchange", action="store_true",
                  help="Print information on what is different but won't be changed")
parser.add_option("--debugchangesd", action="store_true",
                  help="Print security descriptor differences")
parser.add_option("--debugall", action="store_true",
                  help="Print all available information (very verbose)")
parser.add_option("--resetfileacl", action="store_true",
                  help="Force a reset on filesystem acls in sysvol / netlogon share")
parser.add_option("--nontaclfix", action="store_true",
                  help="In full upgrade mode do not try to upgrade sysvol / netlogon acls")
parser.add_option("--fixntacl", action="store_true",
                  help="Only fix NT ACLs in sysvol / netlogon share")
parser.add_option("--db_backup_only", action="store_true",
                  help="Do the backup of the database in the provision, skip the sysvol / netlogon shares")
parser.add_option("--full", action="store_true",
                  help="Perform full upgrade of the samdb (schema, configuration, new objects, ...")

opts = parser.parse_args()[0]

handler = logging.StreamHandler(sys.stdout)
upgrade_logger = logging.getLogger("upgradeprovision")
upgrade_logger.setLevel(logging.INFO)

upgrade_logger.addHandler(handler)

provision_logger = logging.getLogger("provision")
provision_logger.addHandler(handler)

whatToLog = define_what_to_log(opts)

def message(what, text):
    """Print a message if this message type has been selected to be printed

    :param what: Category of the message
    :param text: Message to print """
    if (whatToLog & what) or what <= 0:
        upgrade_logger.info("%s", text)

if len(sys.argv) == 1:
    opts.interactive = True
lp = sambaopts.get_loadparm()
smbconf = lp.configfile

creds = credopts.get_credentials(lp)
creds.set_kerberos_state(DONT_USE_KERBEROS)



def check_for_DNS(refprivate, private):
    """Check if the provision has already the requirement for dynamic dns

    :param refprivate: The path to the private directory of the reference
                       provision
    :param private: The path to the private directory of the upgraded
                    provision"""

    spnfile = "%s/spn_update_list" % private
    dnsfile = "%s/dns_update_list" % private
    namedfile = lp.get("dnsupdate:path")

    if not namedfile:
       namedfile = "%s/named.conf.update" % private

    if not os.path.exists(spnfile):
        shutil.copy("%s/spn_update_list" % refprivate, "%s" % spnfile)

    if not os.path.exists(dnsfile):
        shutil.copy("%s/dns_update_list" % refprivate, "%s" % dnsfile)

    destdir = "%s/new_dns" % private
    dnsdir = "%s/dns" % private

    if not os.path.exists(namedfile):
        if not os.path.exists(destdir):
            os.mkdir(destdir)
        if not os.path.exists(dnsdir):
            os.mkdir(dnsdir)
        shutil.copy("%s/named.conf" % refprivate, "%s/named.conf" % destdir)
        shutil.copy("%s/named.txt" % refprivate, "%s/named.txt" % destdir)
        message(SIMPLE, "It seems that your provision did not integrate "
                "new rules for dynamic dns update of domain related entries")
        message(SIMPLE, "A copy of the new bind configuration files and "
                "template has been put in %s, you should read them and "
                "configure dynamic dns updates" % destdir)


def populate_links(samdb, schemadn):
    """Populate an array with all the back linked attributes

    This attributes that are modified automaticaly when
    front attibutes are changed

    :param samdb: A LDB object for sam.ldb file
    :param schemadn: DN of the schema for the partition"""
    linkedAttHash = get_linked_attributes(Dn(samdb, str(schemadn)), samdb)
    backlinked.extend(linkedAttHash.values())
    for t in linkedAttHash.keys():
        forwardlinked.add(t)

def isReplicated(att):
    """ Indicate if the attribute is replicated or not

    :param att: Name of the attribute to be tested
    :return: True is the attribute is replicated, False otherwise
    """

    return (att not in not_replicated)

def populateNotReplicated(samdb, schemadn):
    """Populate an array with all the attributes that are not replicated

    :param samdb: A LDB object for sam.ldb file
    :param schemadn: DN of the schema for the partition"""
    res = samdb.search(expression="(&(objectclass=attributeSchema)(systemflags:1.2.840.113556.1.4.803:=1))", base=Dn(samdb,
                        str(schemadn)), scope=SCOPE_SUBTREE,
                        attrs=["lDAPDisplayName"])
    for elem in res:
        not_replicated.append(str(elem["lDAPDisplayName"]))


def populate_dnsyntax(samdb, schemadn):
    """Populate an array with all the attributes that have DN synthax
       (oid 2.5.5.1)

    :param samdb: A LDB object for sam.ldb file
    :param schemadn: DN of the schema for the partition"""
    res = samdb.search(expression="(attributeSyntax=2.5.5.1)", base=Dn(samdb,
                        str(schemadn)), scope=SCOPE_SUBTREE,
                        attrs=["lDAPDisplayName"])
    for elem in res:
        dn_syntax_att.append(elem["lDAPDisplayName"])


def sanitychecks(samdb, names):
    """Make some checks before trying to update

    :param samdb: An LDB object opened on sam.ldb
    :param names: list of key provision parameters
    :return: Status of check (1 for Ok, 0 for not Ok) """
    res = samdb.search(expression="objectClass=ntdsdsa", base=str(names.configdn),
                         scope=SCOPE_SUBTREE, attrs=["dn"],
                         controls=["search_options:1:2"])
    if len(res) == 0:
        print "No DC found. Your provision is most probably broken!"
        return False
    elif len(res) != 1:
        print "Found %d domain controllers. For the moment " \
              "upgradeprovision is not able to handle an upgrade on a " \
              "domain with more than one DC. Please demote the other " \
              "DC(s) before upgrading" % len(res)
        return False
    else:
        return True


def print_provision_key_parameters(names):
    """Do a a pretty print of provision parameters

    :param names: list of key provision parameters """
    message(GUESS, "rootdn      :" + str(names.rootdn))
    message(GUESS, "configdn    :" + str(names.configdn))
    message(GUESS, "schemadn    :" + str(names.schemadn))
    message(GUESS, "serverdn    :" + str(names.serverdn))
    message(GUESS, "netbiosname :" + names.netbiosname)
    message(GUESS, "defaultsite :" + names.sitename)
    message(GUESS, "dnsdomain   :" + names.dnsdomain)
    message(GUESS, "hostname    :" + names.hostname)
    message(GUESS, "domain      :" + names.domain)
    message(GUESS, "realm       :" + names.realm)
    message(GUESS, "invocationid:" + names.invocation)
    message(GUESS, "policyguid  :" + names.policyid)
    message(GUESS, "policyguiddc:" + str(names.policyid_dc))
    message(GUESS, "domainsid   :" + str(names.domainsid))
    message(GUESS, "domainguid  :" + names.domainguid)
    message(GUESS, "ntdsguid    :" + names.ntdsguid)
    message(GUESS, "domainlevel :" + str(names.domainlevel))


def handle_special_case(att, delta, new, old, useReplMetadata, basedn, aldb):
    """Define more complicate update rules for some attributes

    :param att: The attribute to be updated
    :param delta: A messageElement object that correspond to the difference
                  between the updated object and the reference one
    :param new: The reference object
    :param old: The Updated object
    :param useReplMetadata: A boolean that indicate if the update process
                use replPropertyMetaData to decide what has to be updated.
    :param basedn: The base DN of the provision
    :param aldb: An ldb object used to build DN
    :return: True to indicate that the attribute should be kept, False for
             discarding it"""

    # We do most of the special case handle if we do not have the
    # highest usn as otherwise the replPropertyMetaData will guide us more
    # correctly
    if not useReplMetadata:
        flag = delta.get(att).flags()
        if (att == "sPNMappings" and flag == FLAG_MOD_REPLACE and
            ldb.Dn(aldb, "CN=Directory Service,CN=Windows NT,"
                        "CN=Services,CN=Configuration,%s" % basedn)
                        == old[0].dn):
            return True
        if (att == "userAccountControl" and flag == FLAG_MOD_REPLACE and
            ldb.Dn(aldb, "CN=Administrator,CN=Users,%s" % basedn)
                        == old[0].dn):
            message(SIMPLE, "We suggest that you change the userAccountControl"
                            " for user Administrator from value %d to %d" %
                            (int(str(old[0][att])), int(str(new[0][att]))))
            return False
        if (att == "minPwdAge" and flag == FLAG_MOD_REPLACE):
            if (long(str(old[0][att])) == 0):
                delta[att] = MessageElement(new[0][att], FLAG_MOD_REPLACE, att)
            return True

        if (att == "member" and flag == FLAG_MOD_REPLACE):
            hash = {}
            newval = []
            changeDelta=0
            for elem in old[0][att]:
                hash[str(elem).lower()]=1
                newval.append(str(elem))

            for elem in new[0][att]:
                if not hash.has_key(str(elem).lower()):
                    changeDelta=1
                    newval.append(str(elem))
            if changeDelta == 1:
                delta[att] = MessageElement(newval, FLAG_MOD_REPLACE, att)
            else:
                delta.remove(att)
            return True

        if (att in ("gPLink", "gPCFileSysPath") and
            flag == FLAG_MOD_REPLACE and
            str(new[0].dn).lower() == str(old[0].dn).lower()):
            delta.remove(att)
            return True

        if att == "forceLogoff":
            ref=0x8000000000000000
            oldval=int(old[0][att][0])
            newval=int(new[0][att][0])
            ref == old and ref == abs(new)
            return True

        if att in ("adminDisplayName", "adminDescription"):
            return True

        if (str(old[0].dn) == "CN=Samba4-Local-Domain, %s" % (names.schemadn)
            and att == "defaultObjectCategory" and flag == FLAG_MOD_REPLACE):
            return True

        if (str(old[0].dn) == "CN=Title, %s" % (str(names.schemadn)) and
                att == "rangeUpper" and flag == FLAG_MOD_REPLACE):
            return True

        if (str(old[0].dn) == "%s" % (str(names.rootdn))
                and att == "subRefs" and flag == FLAG_MOD_REPLACE):
            return True
        #Allow to change revision of ForestUpdates objects
        if (att == "revision" or att == "objectVersion"):
            if str(delta.dn).lower().find("domainupdates") and str(delta.dn).lower().find("forestupdates") > 0:
                return True
        if str(delta.dn).endswith("CN=DisplaySpecifiers, %s" % names.configdn):
            return True

    # This is a bit of special animal as we might have added
    # already SPN entries to the list that has to be modified
    # So we go in detail to try to find out what has to be added ...
    if (att == "servicePrincipalName" and delta.get(att).flags() == FLAG_MOD_REPLACE):
        hash = {}
        newval = []
        changeDelta = 0
        for elem in old[0][att]:
            hash[str(elem)]=1
            newval.append(str(elem))

        for elem in new[0][att]:
            if not hash.has_key(str(elem)):
                changeDelta = 1
                newval.append(str(elem))
        if changeDelta == 1:
            delta[att] = MessageElement(newval, FLAG_MOD_REPLACE, att)
        else:
            delta.remove(att)
        return True

    return False

def dump_denied_change(dn, att, flagtxt, current, reference):
    """Print detailed information about why a change is denied

    :param dn: DN of the object which attribute is denied
    :param att: Attribute that was supposed to be upgraded
    :param flagtxt: Type of the update that should be performed
                    (add, change, remove, ...)
    :param current: Value(s) of the current attribute
    :param reference: Value(s) of the reference attribute"""

    message(CHANGE, "dn= " + str(dn)+" " + att+" with flag " + flagtxt
                + " must not be changed/removed. Discarding the change")
    if att == "objectSid" :
        message(CHANGE, "old : %s" % ndr_unpack(security.dom_sid, current[0]))
        message(CHANGE, "new : %s" % ndr_unpack(security.dom_sid, reference[0]))
    elif att == "rIDPreviousAllocationPool" or att == "rIDAllocationPool":
        message(CHANGE, "old : %s" % int64range2str(current[0]))
        message(CHANGE, "new : %s" % int64range2str(reference[0]))
    else:
        i = 0
        for e in range(0, len(current)):
            message(CHANGE, "old %d : %s" % (i, str(current[e])))
            i+=1
        if reference is not None:
            i = 0
            for e in range(0, len(reference)):
                message(CHANGE, "new %d : %s" % (i, str(reference[e])))
                i+=1

def handle_special_add(samdb, dn, names):
    """Handle special operation (like remove) on some object needed during
    upgrade

    This is mostly due to wrong creation of the object in previous provision.
    :param samdb: An Ldb object representing the SAM database
    :param dn: DN of the object to inspect
    :param names: list of key provision parameters
    """

    dntoremove = None
    objDn = Dn(samdb, "CN=IIS_IUSRS, CN=Builtin, %s" % names.rootdn)
    if dn == objDn :
        #This entry was misplaced lets remove it if it exists
        dntoremove = "CN=IIS_IUSRS, CN=Users, %s" % names.rootdn

    objDn = Dn(samdb,
                "CN=Certificate Service DCOM Access, CN=Builtin, %s" % names.rootdn)
    if dn == objDn:
        #This entry was misplaced lets remove it if it exists
        dntoremove = "CN=Certificate Service DCOM Access,"\
                     "CN=Users, %s" % names.rootdn

    objDn = Dn(samdb, "CN=Cryptographic Operators, CN=Builtin, %s" % names.rootdn)
    if dn == objDn:
        #This entry was misplaced lets remove it if it exists
        dntoremove = "CN=Cryptographic Operators, CN=Users, %s" % names.rootdn

    objDn = Dn(samdb, "CN=Event Log Readers, CN=Builtin, %s" % names.rootdn)
    if dn == objDn:
        #This entry was misplaced lets remove it if it exists
        dntoremove = "CN=Event Log Readers, CN=Users, %s" % names.rootdn

    objDn = Dn(samdb,"CN=System,CN=WellKnown Security Principals,"
                     "CN=Configuration,%s" % names.rootdn)
    if dn == objDn:
        oldDn = Dn(samdb,"CN=Well-Known-Security-Id-System,"
                         "CN=WellKnown Security Principals,"
                         "CN=Configuration,%s" % names.rootdn)

        res = samdb.search(expression="(distinguishedName=%s)" % oldDn,
                            base=str(names.rootdn),
                            scope=SCOPE_SUBTREE, attrs=["dn"],
                            controls=["search_options:1:2"])

        res2 = samdb.search(expression="(distinguishedName=%s)" % dn,
                            base=str(names.rootdn),
                            scope=SCOPE_SUBTREE, attrs=["dn"],
                            controls=["search_options:1:2"])

        if len(res) > 0 and len(res2) == 0:
            message(CHANGE, "Existing object %s must be replaced by %s. "
                            "Renaming old object" % (str(oldDn), str(dn)))
            samdb.rename(oldDn, objDn, ["relax:0", "provision:0"])

        return 0

    if dntoremove is not None:
        res = samdb.search(expression="(cn=RID Set)",
                            base=str(names.rootdn),
                            scope=SCOPE_SUBTREE, attrs=["dn"],
                            controls=["search_options:1:2"])

        if len(res) == 0:
            return 2
        res = samdb.search(expression="(distinguishedName=%s)" % dntoremove,
                            base=str(names.rootdn),
                            scope=SCOPE_SUBTREE, attrs=["dn"],
                            controls=["search_options:1:2"])
        if len(res) > 0:
            message(CHANGE, "Existing object %s must be replaced by %s. "
                            "Removing old object" % (dntoremove, str(dn)))
            samdb.delete(res[0]["dn"])
            return 0

    return 1


def check_dn_nottobecreated(hash, index, listdn):
    """Check if one of the DN present in the list has a creation order
       greater than the current.

    Hash is indexed by dn to be created, with each key
    is associated the creation order.

    First dn to be created has the creation order 0, second has 1, ...
    Index contain the current creation order

    :param hash: Hash holding the different DN of the object to be
                  created as key
    :param index: Current creation order
    :param listdn: List of DNs on which the current DN depends on
    :return: None if the current object do not depend on other
              object or if all object have been created before."""
    if listdn is None:
        return None
    for dn in listdn:
        key = str(dn).lower()
        if hash.has_key(key) and hash[key] > index:
            return str(dn)
    return None



def add_missing_object(ref_samdb, samdb, dn, names, basedn, hash, index):
    """Add a new object if the dependencies are satisfied

    The function add the object if the object on which it depends are already
    created

    :param ref_samdb: Ldb object representing the SAM db of the reference
                       provision
    :param samdb: Ldb object representing the SAM db of the upgraded
                   provision
    :param dn: DN of the object to be added
    :param names: List of key provision parameters
    :param basedn: DN of the partition to be updated
    :param hash: Hash holding the different DN of the object to be
                  created as key
    :param index: Current creation order
    :return: True if the object was created False otherwise"""

    ret = handle_special_add(samdb, dn, names)

    if ret == 2:
        return False

    if ret == 0:
        return True


    reference = ref_samdb.search(expression="(distinguishedName=%s)" % (str(dn)),
                                 base=basedn, scope=SCOPE_SUBTREE,
                                 controls=["search_options:1:2"])
    empty = Message()
    delta = samdb.msg_diff(empty, reference[0])
    delta.dn
    skip = False
    try:
        if str(reference[0].get("cn"))  == "RID Set":
            for klass in reference[0].get("objectClass"):
                if str(klass).lower() == "ridset":
                    skip = True
    finally:
        if delta.get("objectSid"):
            sid = str(ndr_unpack(security.dom_sid, str(reference[0]["objectSid"])))
            m = re.match(r".*-(\d+)$", sid)
            if m and int(m.group(1))>999:
                delta.remove("objectSid")
        for att in attrNotCopied:
            delta.remove(att)
        for att in backlinked:
            delta.remove(att)
        depend_on_yettobecreated = None
        for att in dn_syntax_att:
            depend_on_yet_tobecreated = check_dn_nottobecreated(hash, index,
                                                                delta.get(str(att)))
            if depend_on_yet_tobecreated is not None:
                message(CHANGE, "Object %s depends on %s in attribute %s. "
                                "Delaying the creation" % (dn,
                                          depend_on_yet_tobecreated, att))
                return False

        delta.dn = dn
        if not skip:
            message(CHANGE,"Object %s will be added" % dn)
            samdb.add(delta, ["relax:0", "provision:0"])
        else:
            message(CHANGE,"Object %s was skipped" % dn)

        return True

def gen_dn_index_hash(listMissing):
    """Generate a hash associating the DN to its creation order

    :param listMissing: List of DN
    :return: Hash with DN as keys and creation order as values"""
    hash = {}
    for i in range(0, len(listMissing)):
        hash[str(listMissing[i]).lower()] = i
    return hash

def add_deletedobj_containers(ref_samdb, samdb, names):
    """Add the object containter: CN=Deleted Objects

    This function create the container for each partition that need one and
    then reference the object into the root of the partition

    :param ref_samdb: Ldb object representing the SAM db of the reference
                       provision
    :param samdb: Ldb object representing the SAM db of the upgraded provision
    :param names: List of key provision parameters"""


    wkoPrefix = "B:32:18E2EA80684F11D2B9AA00C04F79F805"
    partitions = [str(names.rootdn), str(names.configdn)]
    for part in partitions:
        ref_delObjCnt = ref_samdb.search(expression="(cn=Deleted Objects)",
                                            base=part, scope=SCOPE_SUBTREE,
                                            attrs=["dn"],
                                            controls=["show_deleted:0",
                                                      "show_recycled:0"])
        delObjCnt = samdb.search(expression="(cn=Deleted Objects)",
                                    base=part, scope=SCOPE_SUBTREE,
                                    attrs=["dn"],
                                    controls=["show_deleted:0",
                                              "show_recycled:0"])
        if len(ref_delObjCnt) > len(delObjCnt):
            reference = ref_samdb.search(expression="cn=Deleted Objects",
                                            base=part, scope=SCOPE_SUBTREE,
                                            controls=["show_deleted:0",
                                                      "show_recycled:0"])
            empty = Message()
            delta = samdb.msg_diff(empty, reference[0])

            delta.dn = Dn(samdb, str(reference[0]["dn"]))
            for att in attrNotCopied:
                delta.remove(att)

            modcontrols = ["relax:0", "provision:0"]
            samdb.add(delta, modcontrols)

            listwko = []
            res = samdb.search(expression="(objectClass=*)", base=part,
                               scope=SCOPE_BASE,
                               attrs=["dn", "wellKnownObjects"])

            targetWKO = "%s:%s" % (wkoPrefix, str(reference[0]["dn"]))
            found = False

            if len(res[0]) > 0:
                wko = res[0]["wellKnownObjects"]

                # The wellKnownObject that we want to add.
                for o in wko:
                    if str(o) == targetWKO:
                        found = True
                    listwko.append(str(o))

            if not found:
                listwko.append(targetWKO)

                delta = Message()
                delta.dn = Dn(samdb, str(res[0]["dn"]))
                delta["wellKnownObjects"] = MessageElement(listwko,
                                                FLAG_MOD_REPLACE,
                                                "wellKnownObjects" )
                samdb.modify(delta)

def add_missing_entries(ref_samdb, samdb, names, basedn, list):
    """Add the missing object whose DN is the list

    The function add the object if the objects on which it depends are
    already created.

    :param ref_samdb: Ldb object representing the SAM db of the reference
                      provision
    :param samdb: Ldb object representing the SAM db of the upgraded
                  provision
    :param dn: DN of the object to be added
    :param names: List of key provision parameters
    :param basedn: DN of the partition to be updated
    :param list: List of DN to be added in the upgraded provision"""

    listMissing = []
    listDefered = list

    while(len(listDefered) != len(listMissing) and len(listDefered) > 0):
        index = 0
        listMissing = listDefered
        listDefered = []
        hashMissing = gen_dn_index_hash(listMissing)
        for dn in listMissing:
            ret = add_missing_object(ref_samdb, samdb, dn, names, basedn,
                                        hashMissing, index)
            index = index + 1
            if ret == 0:
                # DN can't be created because it depends on some
                # other DN in the list
                listDefered.append(dn)

    if len(listDefered) != 0:
        raise ProvisioningError("Unable to insert missing elements: "
                                "circular references")

def handle_links(samdb, att, basedn, dn, value, ref_value, delta):
    """This function handle updates on links

    :param samdb: An LDB object pointing to the updated provision
    :param att: Attribute to update
    :param basedn: The root DN of the provision
    :param dn: The DN of the inspected object
    :param value: The value of the attribute
    :param ref_value: The value of this attribute in the reference provision
    :param delta: The MessageElement object that will be applied for
                   transforming the current provision"""

    res = samdb.search(base=dn, controls=["search_options:1:2", "reveal:1"],
                        attrs=[att])

    blacklist = {}
    hash = {}
    newlinklist = []
    changed = False

    for v in value:
        newlinklist.append(str(v))

    for e in value:
        hash[e] = 1
    # for w2k domain level the reveal won't reveal anything ...
    # it means that we can readd links that were removed on purpose ...
    # Also this function in fact just accept add not removal

    for e in res[0][att]:
        if not hash.has_key(e):
            # We put in the blacklist all the element that are in the "revealed"
            # result and not in the "standard" result
            # This element are links that were removed before and so that
            # we don't wan't to readd
            blacklist[e] = 1

    for e in ref_value:
        if not blacklist.has_key(e) and not hash.has_key(e):
            newlinklist.append(str(e))
            changed = True
    if changed:
        delta[att] = MessageElement(newlinklist, FLAG_MOD_REPLACE, att)
    else:
        delta.remove(att)

    return delta


msg_elt_flag_strs = {
    ldb.FLAG_MOD_ADD: "MOD_ADD",
    ldb.FLAG_MOD_REPLACE: "MOD_REPLACE",
    ldb.FLAG_MOD_DELETE: "MOD_DELETE" }

def checkKeepAttributeOldMtd(delta, att, reference, current,
                                    basedn, samdb):
    """ Check if we should keep the attribute modification or not.
        This function didn't use replicationMetadata to take a decision.

        :param delta: A message diff object
        :param att: An attribute
        :param reference: A message object for the current entry comming from
                            the reference provision.
        :param current: A message object for the current entry commin from
                            the current provision.
        :param basedn: The DN of the partition
        :param samdb: A ldb connection to the sam database of the current provision.

        :return: The modified message diff.
    """
    # Old school way of handling things for pre alpha12 upgrade
    global defSDmodified
    isFirst = False
    txt = ""
    dn = current[0].dn

    for att in list(delta):
        msgElt = delta.get(att)

        if att == "nTSecurityDescriptor":
            defSDmodified = True
            delta.remove(att)
            continue

        if att == "dn":
            continue

        if not hashOverwrittenAtt.has_key(att):
            if msgElt.flags() != FLAG_MOD_ADD:
                if not handle_special_case(att, delta, reference, current,
                                            False, basedn, samdb):
                    if opts.debugchange or opts.debugall:
                        try:
                            dump_denied_change(dn, att,
                                msg_elt_flag_strs[msgElt.flags()],
                                current[0][att], reference[0][att])
                        except KeyError:
                            dump_denied_change(dn, att,
                                msg_elt_flag_strs[msgElt.flags()],
                                current[0][att], None)
                    delta.remove(att)
                continue
        else:
            if hashOverwrittenAtt.get(att)&2**msgElt.flags() :
                continue
            elif  hashOverwrittenAtt.get(att)==never:
                delta.remove(att)
                continue

    return delta

def checkKeepAttributeWithMetadata(delta, att, message, reference, current,
                                    hash_attr_usn, basedn, usns, samdb):
    """ Check if we should keep the attribute modification or not

        :param delta: A message diff object
        :param att: An attribute
        :param message: A function to print messages
        :param reference: A message object for the current entry comming from
                            the reference provision.
        :param current: A message object for the current entry commin from
                            the current provision.
        :param hash_attr_usn: A dictionnary with attribute name as keys,
                                USN and invocation id as values.
        :param basedn: The DN of the partition
        :param usns: A dictionnary with invocation ID as keys and USN ranges
                     as values.
        :param samdb: A ldb object pointing to the sam DB

        :return: The modified message diff.
    """
    global defSDmodified
    isFirst = True
    txt = ""
    dn = current[0].dn

    for att in list(delta):
        if att in ["dn", "objectSid"]:
            delta.remove(att)
            continue

        # We have updated by provision usn information so let's exploit
        # replMetadataProperties
        if att in forwardlinked:
            curval = current[0].get(att, ())
            refval = reference[0].get(att, ())
            delta = handle_links(samdb, att, basedn, current[0]["dn"],
                            curval, refval, delta)
            continue


        if isFirst and len(list(delta)) > 1:
            isFirst = False
            txt = "%s\n" % (str(dn))

        if handle_special_case(att, delta, reference, current, True, None, None):
            # This attribute is "complicated" to handle and handling
            # was done in handle_special_case
            continue

        attrUSN = None
        if hash_attr_usn.get(att):
            [attrUSN, attInvId] = hash_attr_usn.get(att)

        if attrUSN is None:
            # If it's a replicated attribute and we don't have any USN
            # information about it. It means that we never saw it before
            # so let's add it !
            # If it is a replicated attribute but we are not master on it
            # (ie. not initially added in the provision we masterize).
            # attrUSN will be -1
            if isReplicated(att):
                continue
            else:
                message(CHANGE, "Non replicated attribute %s changed" % att)
                continue

        if att == "nTSecurityDescriptor":
            cursd = ndr_unpack(security.descriptor,
                str(current[0]["nTSecurityDescriptor"]))
            cursddl = cursd.as_sddl(names.domainsid)
            refsd = ndr_unpack(security.descriptor,
                str(reference[0]["nTSecurityDescriptor"]))
            refsddl = refsd.as_sddl(names.domainsid)

            diff = get_diff_sddls(refsddl, cursddl)
            if diff == "":
                # FIXME find a way to have it only with huge huge verbose mode
                # message(CHANGE, "%ssd are identical" % txt)
                # txt = ""
                delta.remove(att)
                continue
            else:
                delta.remove(att)
                message(CHANGESD, "%ssd are not identical:\n%s" % (txt, diff))
                txt = ""
                if attrUSN == -1:
                    message(CHANGESD, "But the SD has been changed by someonelse "\
                                    "so it's impossible to know if the difference"\
                                    " cames from the modification or from a previous bug")
                    dnNotToRecalculate.append(str(dn))
                else:
                    dnToRecalculate.append(str(dn))
                continue

        if attrUSN == -1:
            # This attribute was last modified by another DC forget
            # about it
            message(CHANGE, "%sAttribute: %s has been "
                    "created/modified/deleted by another DC. "
                    "Doing nothing" % (txt, att))
            txt = ""
            delta.remove(att)
            continue
        elif not usn_in_range(int(attrUSN), usns.get(attInvId)):
            message(CHANGE, "%sAttribute: %s was not "
                            "created/modified/deleted during a "
                            "provision or upgradeprovision. Current "
                            "usn: %d. Doing nothing" % (txt, att,
                                                        attrUSN))
            txt = ""
            delta.remove(att)
            continue
        else:
            if att == "defaultSecurityDescriptor":
                defSDmodified = True
            if attrUSN:
                message(CHANGE, "%sAttribute: %s will be modified"
                                "/deleted it was last modified "
                                "during a provision. Current usn: "
                                "%d" % (txt, att, attrUSN))
                txt = ""
            else:
                message(CHANGE, "%sAttribute: %s will be added because "
                                "it did not exist before" % (txt, att))
                txt = ""
            continue

    return delta

def update_present(ref_samdb, samdb, basedn, listPresent, usns):
    """ This function updates the object that are already present in the
        provision

    :param ref_samdb: An LDB object pointing to the reference provision
    :param samdb: An LDB object pointing to the updated provision
    :param basedn: A string with the value of the base DN for the provision
                   (ie. DC=foo, DC=bar)
    :param listPresent: A list of object that is present in the provision
    :param usns: A list of USN range modified by previous provision and
                 upgradeprovision grouped by invocation ID
    """

    # This hash is meant to speedup lookup of attribute name from an oid,
    # it's for the replPropertyMetaData handling
    hash_oid_name = {}
    res = samdb.search(expression="objectClass=attributeSchema", base=basedn,
                        controls=["search_options:1:2"], attrs=["attributeID",
                        "lDAPDisplayName"])
    if len(res) > 0:
        for e in res:
            strDisplay = str(e.get("lDAPDisplayName"))
            hash_oid_name[str(e.get("attributeID"))] = strDisplay
    else:
        msg = "Unable to insert missing elements: circular references"
        raise ProvisioningError(msg)

    changed = 0
    controls = ["search_options:1:2", "sd_flags:1:0"]
    if usns is not None:
            message(CHANGE, "Using replPropertyMetadata for change selection")
    for dn in listPresent:
        reference = ref_samdb.search(expression="(distinguishedName=%s)" % (str(dn)), base=basedn,
                                        scope=SCOPE_SUBTREE,
                                        controls=controls)
        current = samdb.search(expression="(distinguishedName=%s)" % (str(dn)), base=basedn,
                                scope=SCOPE_SUBTREE, controls=controls)

        if (
             (str(current[0].dn) != str(reference[0].dn)) and
             (str(current[0].dn).upper() == str(reference[0].dn).upper())
           ):
            message(CHANGE, "Names are the same except for the case. "
                            "Renaming %s to %s" % (str(current[0].dn),
                                                   str(reference[0].dn)))
            identic_rename(samdb, reference[0].dn)
            current = samdb.search(expression="(distinguishedName=%s)" % (str(dn)), base=basedn,
                                    scope=SCOPE_SUBTREE,
                                    controls=controls)

        delta = samdb.msg_diff(current[0], reference[0])

        for att in backlinked:
            delta.remove(att)

        for att in attrNotCopied:
            delta.remove(att)

        delta.remove("name")

        nb_items = len(list(delta))

        if nb_items == 1:
            continue

        if nb_items > 1 and usns is not None:
            # Fetch the replPropertyMetaData
            res = samdb.search(expression="(distinguishedName=%s)" % (str(dn)), base=basedn,
                                scope=SCOPE_SUBTREE, controls=controls,
                                attrs=["replPropertyMetaData"])
            ctr = ndr_unpack(drsblobs.replPropertyMetaDataBlob,
                                str(res[0]["replPropertyMetaData"])).ctr

            hash_attr_usn = {}
            for o in ctr.array:
                # We put in this hash only modification
                # made on the current host
                att = hash_oid_name[samdb.get_oid_from_attid(o.attid)]
                if str(o.originating_invocation_id) in usns.keys():
                    hash_attr_usn[att] = [o.originating_usn, str(o.originating_invocation_id)]
                else:
                    hash_attr_usn[att] = [-1, None]

        if usns is not None:
            delta = checkKeepAttributeWithMetadata(delta, att, message, reference,
                                                    current, hash_attr_usn,
                                                    basedn, usns, samdb)
        else:
            delta =  checkKeepAttributeOldMtd(delta, att, reference, current, basedn, samdb)

        delta.dn = dn


        if len(delta) >1:
            # Skip dn as the value is not really changed ...
            attributes=", ".join(delta.keys()[1:])
            modcontrols = []
            relaxedatt = ['iscriticalsystemobject', 'grouptype']
            # Let's try to reduce as much as possible the use of relax control
            for attr in delta.keys():
                if attr.lower() in relaxedatt:
                    modcontrols = ["relax:0", "provision:0"]
            message(CHANGE, "%s is different from the reference one, changed"
                            " attributes: %s\n" % (dn, attributes))
            changed += 1
            samdb.modify(delta, modcontrols)
    return changed

def reload_full_schema(samdb, names):
    """Load the updated schema with all the new and existing classes
       and attributes.

    :param samdb: An LDB object connected to the sam.ldb of the update
                  provision
    :param names: List of key provision parameters
    """

    schemadn = str(names.schemadn)
    current = samdb.search(expression="objectClass=*", base=schemadn,
                                scope=SCOPE_SUBTREE)
    schema_ldif = ""
    prefixmap_data = ""

    for ent in current:
        schema_ldif += samdb.write_ldif(ent, ldb.CHANGETYPE_NONE)

    prefixmap_data = open(setup_path("prefixMap.txt"), 'r').read()
    prefixmap_data = b64encode(prefixmap_data)

    # We don't actually add this ldif, just parse it
    prefixmap_ldif = "dn: %s\nprefixMap:: %s\n\n" % (schemadn, prefixmap_data)

    dsdb._dsdb_set_schema_from_ldif(samdb, prefixmap_ldif, schema_ldif, schemadn)


def update_partition(ref_samdb, samdb, basedn, names, schema, provisionUSNs, prereloadfunc):
    """Check differences between the reference provision and the upgraded one.

    It looks for all objects which base DN is name.

    This function will also add the missing object and update existing object
    to add or remove attributes that were missing.

    :param ref_sambdb: An LDB object conntected to the sam.ldb of the
                       reference provision
    :param samdb: An LDB object connected to the sam.ldb of the update
                  provision
    :param basedn: String value of the DN of the partition
    :param names: List of key provision parameters
    :param schema: A Schema object
    :param provisionUSNs:  A dictionnary with range of USN modified during provision
                            or upgradeprovision. Ranges are grouped by invocationID.
    :param prereloadfunc: A function that must be executed just before the reload
                  of the schema
    """

    hash_new = {}
    hash = {}
    listMissing = []
    listPresent = []
    reference = []
    current = []

    # Connect to the reference provision and get all the attribute in the
    # partition referred by name
    reference = ref_samdb.search(expression="objectClass=*", base=basedn,
                                    scope=SCOPE_SUBTREE, attrs=["dn"],
                                    controls=["search_options:1:2"])

    current = samdb.search(expression="objectClass=*", base=basedn,
                                scope=SCOPE_SUBTREE, attrs=["dn"],
                                controls=["search_options:1:2"])
    # Create a hash for speeding the search of new object
    for i in range(0, len(reference)):
        hash_new[str(reference[i]["dn"]).lower()] = reference[i]["dn"]

    # Create a hash for speeding the search of existing object in the
    # current provision
    for i in range(0, len(current)):
        hash[str(current[i]["dn"]).lower()] = current[i]["dn"]


    for k in hash_new.keys():
        if not hash.has_key(k):
            if not str(hash_new[k]) == "CN=Deleted Objects, %s" % names.rootdn:
                listMissing.append(hash_new[k])
        else:
            listPresent.append(hash_new[k])

    # Sort the missing object in order to have object of the lowest level
    # first (which can be containers for higher level objects)
    listMissing.sort(dn_sort)
    listPresent.sort(dn_sort)

    # The following lines is to load the up to
    # date schema into our current LDB
    # a complete schema is needed as the insertion of attributes
    # and class is done against it
    # and the schema is self validated
    samdb.set_schema(schema)
    try:
        message(SIMPLE, "There are %d missing objects" % (len(listMissing)))
        add_deletedobj_containers(ref_samdb, samdb, names)

        add_missing_entries(ref_samdb, samdb, names, basedn, listMissing)

        prereloadfunc()
        message(SIMPLE, "Reloading a merged schema, which might trigger "
                        "reindexing so please be patient")
        reload_full_schema(samdb, names)
        message(SIMPLE, "Schema reloaded!")

        changed = update_present(ref_samdb, samdb, basedn, listPresent,
                                    provisionUSNs)
        message(SIMPLE, "There are %d changed objects" % (changed))
        return 1

    except StandardError, err:
        message(ERROR, "Exception during upgrade of samdb:")
        (typ, val, tb) = sys.exc_info()
        traceback.print_exception(typ, val, tb)
        return 0


def check_updated_sd(ref_sam, cur_sam, names):
    """Check if the security descriptor in the upgraded provision are the same
       as the reference

    :param ref_sam: A LDB object connected to the sam.ldb file used as
                    the reference provision
    :param cur_sam: A LDB object connected to the sam.ldb file used as
                    upgraded provision
    :param names: List of key provision parameters"""
    reference = ref_sam.search(expression="objectClass=*", base=str(names.rootdn),
                                scope=SCOPE_SUBTREE,
                                attrs=["dn", "nTSecurityDescriptor"],
                                controls=["search_options:1:2"])
    current = cur_sam.search(expression="objectClass=*", base=str(names.rootdn),
                                scope=SCOPE_SUBTREE,
                                attrs=["dn", "nTSecurityDescriptor"],
                                controls=["search_options:1:2"])
    hash = {}
    for i in range(0, len(reference)):
        refsd = ndr_unpack(security.descriptor,
                    str(reference[i]["nTSecurityDescriptor"]))
        hash[str(reference[i]["dn"]).lower()] = refsd.as_sddl(names.domainsid)


    for i in range(0, len(current)):
        key = str(current[i]["dn"]).lower()
        if hash.has_key(key):
            cursd = ndr_unpack(security.descriptor,
                        str(current[i]["nTSecurityDescriptor"]))
            sddl = cursd.as_sddl(names.domainsid)
            if sddl != hash[key]:
                txt = get_diff_sddls(hash[key], sddl, False)
                if txt != "":
                    message(CHANGESD, "On object %s ACL is different"
                                      " \n%s" % (current[i]["dn"], txt))



def fix_partition_sd(samdb, names):
    """This function fix the SD for partition containers (basedn, configdn, ...)
    This is needed because some provision use to have broken SD on containers

    :param samdb: An LDB object pointing to the sam of the current provision
    :param names: A list of key provision parameters
    """
    alwaysRecalculate = False
    if len(dnToRecalculate) == 0 and len(dnNotToRecalculate) == 0:
        alwaysRecalculate = True


    # NC's DN can't be both in dnToRecalculate and dnNotToRecalculate
    # First update the SD for the rootdn
    if alwaysRecalculate or str(names.rootdn) in dnToRecalculate:
        delta = Message()
        delta.dn = Dn(samdb, str(names.rootdn))
        descr = get_domain_descriptor(names.domainsid)
        delta["nTSecurityDescriptor"] = MessageElement(descr, FLAG_MOD_REPLACE,
                                                        "nTSecurityDescriptor")
        samdb.modify(delta)

    # Then the config dn
    if alwaysRecalculate or str(names.configdn) in dnToRecalculate:
        delta = Message()
        delta.dn = Dn(samdb, str(names.configdn))
        descr = get_config_descriptor(names.domainsid)
        delta["nTSecurityDescriptor"] = MessageElement(descr, FLAG_MOD_REPLACE,
                                                        "nTSecurityDescriptor" )
        samdb.modify(delta)

    # Then the schema dn
    if alwaysRecalculate or str(names.schemadn) in dnToRecalculate:
        delta = Message()
        delta.dn = Dn(samdb, str(names.schemadn))
        descr = get_schema_descriptor(names.domainsid)
        delta["nTSecurityDescriptor"] = MessageElement(descr, FLAG_MOD_REPLACE,
                                                        "nTSecurityDescriptor" )
        samdb.modify(delta)

def rebuild_sd(samdb, names):
    """Rebuild security descriptor of the current provision from scratch

    During the different pre release of samba4 security descriptors (SD)
    were notarly broken (up to alpha11 included)
    This function allow to get them back in order, this function make the
    assumption that nobody has modified manualy an SD
    and so SD can be safely recalculated from scratch to get them right.

    :param names: List of key provision parameters"""

    fix_partition_sd(samdb, names)

    # List of namming contexts
    listNC = [str(names.rootdn), str(names.configdn), str(names.schemadn)]
    hash = {}
    if len(dnToRecalculate) == 0:
        res = samdb.search(expression="objectClass=*", base=str(names.rootdn),
                        scope=SCOPE_SUBTREE, attrs=["dn", "whenCreated"],
                        controls=["search_options:1:2"])
        for obj in res:
                hash[str(obj["dn"])] = obj["whenCreated"]
    else:
        for dn in dnToRecalculate:
            if hash.has_key(dn):
                continue
            # fetch each dn to recalculate and their child within the same partition
            res = samdb.search(expression="objectClass=*", base=dn,
                        scope=SCOPE_SUBTREE, attrs=["dn", "whenCreated"])
            for obj in res:
                hash[str(obj["dn"])] = obj["whenCreated"]

    listKeys = list(set(hash.keys()))
    listKeys.sort(dn_sort)

    if len(dnToRecalculate) != 0:
        message(CHANGESD, "%d DNs have been marked as needed to be recalculated"\
                            ", recalculating %d due to inheritance"
                            % (len(dnToRecalculate), len(listKeys)))

    for key in listKeys:
        if (key in listNC or
                    key in dnNotToRecalculate):
            continue
        delta = Message()
        delta.dn = Dn(samdb, key)
        try:
            delta["whenCreated"] = MessageElement(hash[key], FLAG_MOD_REPLACE,
                                                    "whenCreated" )
            samdb.modify(delta, ["recalculate_sd:0","relax:0"])
        except LdbError, e:
            samdb.transaction_cancel()
            res = samdb.search(expression="objectClass=*", base=str(names.rootdn),
                                scope=SCOPE_SUBTREE,
                                attrs=["dn", "nTSecurityDescriptor"],
                                controls=["search_options:1:2"])
            badsd = ndr_unpack(security.descriptor,
                        str(res[0]["nTSecurityDescriptor"]))
            message(ERROR, "On %s bad stuff %s" % (str(delta.dn),badsd.as_sddl(names.domainsid)))
            return

def hasATProvision(samdb):
        entry = samdb.search(expression="(distinguishedName=@PROVISION)", base = "",
                                scope=SCOPE_BASE,
                                attrs=["dn"])

        if entry != None and len(entry) == 1:
            return True
        else:
            return False

def removeProvisionUSN(samdb):
        attrs = [samba.provision.LAST_PROVISION_USN_ATTRIBUTE, "dn"]
        entry = samdb.search(expression="(distinguishedName=@PROVISION)", base = "",
                                scope=SCOPE_BASE,
                                attrs=attrs)
        empty = Message()
        empty.dn = entry[0].dn
        delta = samdb.msg_diff(entry[0], empty)
        delta.remove("dn")
        delta.dn = entry[0].dn
        samdb.modify(delta)

def remove_stored_generated_attrs(paths, creds, session, lp):
    """Remove previously stored constructed attributes

    :param paths: List of paths for different provision objects
                        from the upgraded provision
    :param creds: A credential object
    :param session: A session object
    :param lp: A line parser object
    :return: An associative array whose key are the different constructed
             attributes and the value the dn where this attributes were found.
     """


def simple_update_basesamdb(newpaths, paths, names):
    """Update the provision container db: sam.ldb
    This function is aimed at very old provision (before alpha9)

    :param newpaths: List of paths for different provision objects
                        from the reference provision
    :param paths: List of paths for different provision objects
                        from the upgraded provision
    :param names: List of key provision parameters"""

    message(SIMPLE, "Copy samdb")
    shutil.copy(newpaths.samdb, paths.samdb)

    message(SIMPLE, "Update partitions filename if needed")
    schemaldb = os.path.join(paths.private_dir, "schema.ldb")
    configldb = os.path.join(paths.private_dir, "configuration.ldb")
    usersldb = os.path.join(paths.private_dir, "users.ldb")
    samldbdir = os.path.join(paths.private_dir, "sam.ldb.d")

    if not os.path.isdir(samldbdir):
        os.mkdir(samldbdir)
        os.chmod(samldbdir, 0700)
    if os.path.isfile(schemaldb):
        shutil.copy(schemaldb, os.path.join(samldbdir,
                                            "%s.ldb"%str(names.schemadn).upper()))
        os.remove(schemaldb)
    if os.path.isfile(usersldb):
        shutil.copy(usersldb, os.path.join(samldbdir,
                                            "%s.ldb"%str(names.rootdn).upper()))
        os.remove(usersldb)
    if os.path.isfile(configldb):
        shutil.copy(configldb, os.path.join(samldbdir,
                                            "%s.ldb"%str(names.configdn).upper()))
        os.remove(configldb)


def update_privilege(ref_private_path, cur_private_path):
    """Update the privilege database

    :param ref_private_path: Path to the private directory of the reference
                             provision.
    :param cur_private_path: Path to the private directory of the current
                             (and to be updated) provision."""
    message(SIMPLE, "Copy privilege")
    shutil.copy(os.path.join(ref_private_path, "privilege.ldb"),
                os.path.join(cur_private_path, "privilege.ldb"))


def update_samdb(ref_samdb, samdb, names, provisionUSNs, schema, prereloadfunc):
    """Upgrade the SAM DB contents for all the provision partitions

    :param ref_sambdb: An LDB object conntected to the sam.ldb of the reference
                       provision
    :param samdb: An LDB object connected to the sam.ldb of the update
                  provision
    :param names: List of key provision parameters
    :param provisionUSNs:  A dictionnary with range of USN modified during provision
                            or upgradeprovision. Ranges are grouped by invocationID.
    :param schema: A Schema object that represent the schema of the provision
    :param prereloadfunc: A function that must be executed just before the reload
                  of the schema
    """

    message(SIMPLE, "Starting update of samdb")
    ret = update_partition(ref_samdb, samdb, str(names.rootdn), names,
                            schema, provisionUSNs, prereloadfunc)
    if ret:
        message(SIMPLE, "Update of samdb finished")
        return 1
    else:
        message(SIMPLE, "Update failed")
        return 0


def backup_provision(paths, dir, only_db):
    """This function backup the provision files so that a rollback
    is possible

    :param paths: Paths to different objects
    :param dir: Directory where to store the backup
    :param only_db: Skip sysvol for users with big sysvol
    """
    if paths.sysvol and not only_db:
        copytree_with_xattrs(paths.sysvol, os.path.join(dir, "sysvol"))
    shutil.copy2(paths.samdb, dir)
    shutil.copy2(paths.secrets, dir)
    shutil.copy2(paths.idmapdb, dir)
    shutil.copy2(paths.privilege, dir)
    if os.path.isfile(os.path.join(paths.private_dir,"eadb.tdb")):
        shutil.copy2(os.path.join(paths.private_dir,"eadb.tdb"), dir)
    shutil.copy2(paths.smbconf, dir)
    shutil.copy2(os.path.join(paths.private_dir,"secrets.keytab"), dir)

    samldbdir = os.path.join(paths.private_dir, "sam.ldb.d")
    if not os.path.isdir(samldbdir):
        samldbdir = paths.private_dir
        schemaldb = os.path.join(paths.private_dir, "schema.ldb")
        configldb = os.path.join(paths.private_dir, "configuration.ldb")
        usersldb = os.path.join(paths.private_dir, "users.ldb")
        shutil.copy2(schemaldb, dir)
        shutil.copy2(usersldb, dir)
        shutil.copy2(configldb, dir)
    else:
        shutil.copytree(samldbdir, os.path.join(dir, "sam.ldb.d"))


def sync_calculated_attributes(samdb, names):
   """Synchronize attributes used for constructed ones, with the
      old constructed that were stored in the database.

      This apply for instance to msds-keyversionnumber that was
      stored and that is now constructed from replpropertymetadata.

      :param samdb: An LDB object attached to the currently upgraded samdb
      :param names: Various key parameter about current provision.
   """
   listAttrs = ["msDs-KeyVersionNumber"]
   hash = search_constructed_attrs_stored(samdb, names.rootdn, listAttrs)
   if hash.has_key("msDs-KeyVersionNumber"):
       increment_calculated_keyversion_number(samdb, names.rootdn,
                                            hash["msDs-KeyVersionNumber"])

# Synopsis for updateprovision
# 1) get path related to provision to be update (called current)
# 2) open current provision ldbs
# 3) fetch the key provision parameter (domain sid, domain guid, invocationid
#    of the DC ....)
# 4) research of lastProvisionUSN in order to get ranges of USN modified
#    by either upgradeprovision or provision
# 5) creation of a new provision the latest version of provision script
#    (called reference)
# 6) get reference provision paths
# 7) open reference provision ldbs
# 8) setup helpers data that will help the update process
# 9) update the privilege ldb by copying the one of referecence provision to
#    the current provision
# 10)get the oemInfo field, this field contains information about the different
#    provision that have been done
# 11)Depending  on whether oemInfo has the string "alpha9" or alphaxx (x as an
#    integer) or none of this the following things are done
#    A) When alpha9 or alphaxx is present
#       The base sam.ldb file is updated by looking at the difference between
#       referrence one and the current one. Everything is copied with the
#       exception of lastProvisionUSN attributes.
#    B) Other case (it reflect that that provision was done before alpha9)
#       The base sam.ldb of the reference provision is copied over
#       the current one, if necessary ldb related to partitions are moved
#       and renamed
# The highest used USN is fetched so that changed by upgradeprovision
# usn can be tracked
# 12)A Schema object is created, it will be used to provide a complete
#    schema to current provision during update (as the schema of the
#    current provision might not be complete and so won't allow some
#    object to be created)
# 13)Proceed to full update of sam DB (see the separate paragraph about i)
# 14)The secrets db is updated by pull all the difference from the reference
#    provision into the current provision
# 15)As the previous step has most probably modified the password stored in
#    in secret for the current DC, a new password is generated,
#    the kvno is bumped and the entry in samdb is also updated
# 16)For current provision older than alpha9, we must fix the SD a little bit
#    administrator to update them because SD used to be generated with the
#    system account before alpha9.
# 17)The highest usn modified so far is searched in the database it will be
#    the upper limit for usn modified during provision.
#    This is done before potential SD recalculation because we do not want
#    SD modified during recalculation to be marked as modified during provision
#    (and so possibly remplaced at next upgradeprovision)
# 18)Rebuilt SD if the flag indicate to do so
# 19)Check difference between SD of reference provision and those of the
#    current provision. The check is done by getting the sddl representation
#    of the SD. Each sddl in chuncked into parts (user,group,dacl,sacl)
#    Each part is verified separetly, for dacl and sacl ACL is splited into
#    ACEs and each ACE is verified separately (so that a permutation in ACE
#    didn't raise as an error).
# 20)The oemInfo field is updated to add information about the fact that the
#    provision has been updated by the upgradeprovision version xxx
#    (the version is the one obtained when starting samba with the --version
#    parameter)
# 21)Check if the current provision has all the settings needed for dynamic
#    DNS update to work (that is to say the provision is newer than
#    january 2010). If not dns configuration file from reference provision
#    are copied in a sub folder and the administrator is invited to
#    do what is needed.
# 22)If the lastProvisionUSN attribute was present it is updated to add
#    the range of usns modified by the current upgradeprovision


# About updating the sam DB
# The update takes place in update_partition function
# This function read both current and reference provision and list all
# the available DN of objects
# If the string representation of a DN in reference provision is
# equal to the string representation of a DN in current provision
# (without taking care of case) then the object is flaged as being
# present. If the object is not present in current provision the object
# is being flaged as missing in current provision. Object present in current
# provision but not in reference provision are ignored.
# Once the list of objects present and missing is done, the deleted object
# containers are created in the differents partitions (if missing)
#
# Then the function add_missing_entries is called
# This function will go through the list of missing entries by calling
# add_missing_object for the given object. If this function returns 0
# it means that the object needs some other object in order to be created
# The object is reappended at the end of the list to be created later
# (and preferably after all the needed object have been created)
# The function keeps on looping on the list of object to be created until
# it's empty or that the number of defered creation is equal to the number
# of object that still needs to be created.

# The function add_missing_object will first check if the object can be created.
# That is to say that it didn't depends other not yet created objects
# If requisit can't be fullfilled it exists with 0
# Then it will try to create the missing entry by creating doing
# an ldb_message_diff between the object in the reference provision and
# an empty object.
# This resulting object is filtered to remove all the back link attribute
# (ie. memberOf) as they will be created by the other linked object (ie.
# the one with the member attribute)
# All attributes specified in the attrNotCopied array are
# also removed it's most of the time generated attributes

# After missing entries have been added the update_partition function will
# take care of object that exist but that need some update.
# In order to do so the function update_present is called with the list
# of object that are present in both provision and that might need an update.

# This function handle first case mismatch so that the DN in the current
# provision have the same case as in reference provision

# It will then construct an associative array consiting of attributes as
# key and invocationid as value( if the originating invocation id is
# different from the invocation id of the current DC the value is -1 instead).

# If the range of provision modified attributes is present, the function will
# use the replMetadataProperty update method which is the following:
#  Removing attributes that should not be updated: rIDAvailablePool, objectSid,
#   creationTime, msDs-KeyVersionNumber, oEMInformation
#  Check for each attribute if its usn is within one of the modified by
#   provision range and if its originating id is the invocation id of the
#   current DC, then validate the update from reference to current.
#   If not or if there is no replMetatdataProperty for this attribute then we
#   do not update it.
# Otherwise (case the range of provision modified attribute is not present) it
# use the following process:
#  All attributes that need to be added are accepted at the exeption of those
#   listed in hashOverwrittenAtt, in this case the attribute needs to have the
#   correct flags specified.
#  For attributes that need to be modified or removed, a check is performed
#  in OverwrittenAtt, if the attribute is present and the modification flag
#  (remove, delete) is one of those listed for this attribute then modification
#  is accepted. For complicated handling of attribute update, the control is passed
#  to handle_special_case



if __name__ == '__main__':
    global defSDmodified
    defSDmodified = False

    if opts.nontaclfix and opts.fixntacl:
        message(SIMPLE, "nontaclfix and fixntacl are mutally exclusive")
    # From here start the big steps of the program
    # 1) First get files paths
    paths = get_paths(param, smbconf=smbconf)
    # Get ldbs with the system session, it is needed for searching
    # provision parameters
    session = system_session()

    # This variable will hold the last provision USN once if it exists.
    minUSN = 0
    # 2)
    ldbs = get_ldbs(paths, creds, session, lp)
    backupdir = tempfile.mkdtemp(dir=paths.private_dir,
                                    prefix="backupprovision")
    backup_provision(paths, backupdir, opts.db_backup_only)
    try:
        ldbs.startTransactions()

        # 3) Guess all the needed names (variables in fact) from the current
        # provision.
        names = find_provision_key_parameters(ldbs.sam, ldbs.secrets, ldbs.idmap,
                                                paths, smbconf, lp)
        # 4)
        lastProvisionUSNs = get_last_provision_usn(ldbs.sam)
        if lastProvisionUSNs is not None:
            v = 0
            for k in lastProvisionUSNs.keys():
                for r in lastProvisionUSNs[k]:
                    v = v + 1

            message(CHANGE,
                "Find last provision USN, %d invocation(s) for a total of %d ranges" % \
                            (len(lastProvisionUSNs.keys()), v /2 ))

            if lastProvisionUSNs.get("default") != None:
                message(CHANGE, "Old style for usn ranges used")
                lastProvisionUSNs[str(names.invocation)] = lastProvisionUSNs["default"]
                del lastProvisionUSNs["default"]
        else:
            message(SIMPLE, "Your provision lacks provision range information")
            if confirm("Do you want to run findprovisionusnranges to try to find them ?", False):
                ldbs.groupedRollback()
                minobj = 5
                (hash_id, nb_obj) = findprovisionrange(ldbs.sam, ldb.Dn(ldbs.sam, str(names.rootdn)))
                message(SIMPLE, "Here is a list of changes that modified more than %d objects in 1 minute." % minobj)
                message(SIMPLE, "Usually changes made by provision and upgradeprovision are those who affect a couple"\
                        " of hundred of objects or more")
                message(SIMPLE, "Total number of objects: %d" % nb_obj)
                message(SIMPLE, "")

                print_provision_ranges(hash_id, minobj, None, str(paths.samdb), str(names.invocation))

                message(SIMPLE, "Once you applied/adapted the change(s) please restart the upgradeprovision script")
                sys.exit(0)

        # Objects will be created with the admin session
        # (not anymore system session)
        adm_session = admin_session(lp, str(names.domainsid))
        # So we reget handle on objects
        # ldbs = get_ldbs(paths, creds, adm_session, lp)
        if not opts.fixntacl:
            if not sanitychecks(ldbs.sam, names):
                message(SIMPLE, "Sanity checks for the upgrade have failed. "
                        "Check the messages and correct the errors "
                        "before rerunning upgradeprovision")
                ldbs.groupedRollback()
                sys.exit(1)

            # Let's see provision parameters
            print_provision_key_parameters(names)

            # 5) With all this information let's create a fresh new provision used as
            # reference
            message(SIMPLE, "Creating a reference provision")
            provisiondir = tempfile.mkdtemp(dir=paths.private_dir,
                            prefix="referenceprovision")
            result = newprovision(names, creds, session, smbconf, provisiondir,
                    provision_logger)
            result.report_logger(provision_logger)

            # TODO
            # 6) and 7)
            # We need to get a list of object which SD is directly computed from
            # defaultSecurityDescriptor.
            # This will allow us to know which object we can rebuild the SD in case
            # of change of the parent's SD or of the defaultSD.
            # Get file paths of this new provision
            newpaths = get_paths(param, targetdir=provisiondir)
            new_ldbs = get_ldbs(newpaths, creds, session, lp)
            new_ldbs.startTransactions()

            populateNotReplicated(new_ldbs.sam, names.schemadn)
            # 8) Populate some associative array to ease the update process
            # List of attribute which are link and backlink
            populate_links(new_ldbs.sam, names.schemadn)
            # List of attribute with ASN DN synthax)
            populate_dnsyntax(new_ldbs.sam, names.schemadn)
            # 9)
            update_privilege(newpaths.private_dir, paths.private_dir)
            # 10)
            oem = getOEMInfo(ldbs.sam, str(names.rootdn))
            # Do some modification on sam.ldb
            ldbs.groupedCommit()
            new_ldbs.groupedCommit()
            deltaattr = None
        # 11)
            message(GUESS, oem)
            if oem is None or hasATProvision(ldbs.sam) or re.match(".*alpha((9)|(\d\d+)).*", str(oem)):
                # 11) A
                # Starting from alpha9 we can consider that the structure is quite ok
                # and that we should do only dela
                deltaattr = delta_update_basesamdb(newpaths.samdb,
                                paths.samdb,
                                creds,
                                session,
                                lp,
                                message)
            else:
                # 11) B
                simple_update_basesamdb(newpaths, paths, names)
                ldbs = get_ldbs(paths, creds, session, lp)
                removeProvisionUSN(ldbs.sam)

            ldbs.startTransactions()
            minUSN = int(str(get_max_usn(ldbs.sam, str(names.rootdn)))) + 1
            new_ldbs.startTransactions()

            # 12)
            schema = Schema(names.domainsid, schemadn=str(names.schemadn))
            # We create a closure that will be invoked just before schema reload
            def schemareloadclosure():
                basesam = Ldb(paths.samdb, session_info=session, credentials=creds, lp=lp,
                        options=["modules:"])
                doit = False
                if deltaattr is not None and len(deltaattr) > 1:
                    doit = True
                if doit:
                    deltaattr.remove("dn")
                    for att in deltaattr:
                        if att.lower() == "dn":
                            continue
                        if (deltaattr.get(att) is not None
                            and deltaattr.get(att).flags() != FLAG_MOD_ADD):
                            doit = False
                        elif deltaattr.get(att) is None:
                            doit = False
                if doit:
                    message(CHANGE, "Applying delta to @ATTRIBUTES")
                    deltaattr.dn = ldb.Dn(basesam, "@ATTRIBUTES")
                    basesam.modify(deltaattr)
                else:
                    message(CHANGE, "Not applying delta to @ATTRIBUTES because "
                        "there is not only add")
            # 13)
            if opts.full:
                if not update_samdb(new_ldbs.sam, ldbs.sam, names, lastProvisionUSNs,
                        schema, schemareloadclosure):
                    message(SIMPLE, "Rolling back all changes. Check the cause"
                            " of the problem")
                    message(SIMPLE, "Your system is as it was before the upgrade")
                    ldbs.groupedRollback()
                    new_ldbs.groupedRollback()
                    shutil.rmtree(provisiondir)
                    sys.exit(1)
            else:
                # Try to reapply the change also when we do not change the sam
                # as the delta_upgrade
                schemareloadclosure()
                sync_calculated_attributes(ldbs.sam, names)
                res = ldbs.sam.search(expression="(samaccountname=dns)",
                        scope=SCOPE_SUBTREE, attrs=["dn"],
                        controls=["search_options:1:2"])
                if len(res) > 0:
                    message(SIMPLE, "You still have the old DNS object for managing "
                            "dynamic DNS, but you didn't supply --full so "
                            "a correct update can't be done")
                    ldbs.groupedRollback()
                    new_ldbs.groupedRollback()
                    shutil.rmtree(provisiondir)
                    sys.exit(1)
            # 14)
            update_secrets(new_ldbs.secrets, ldbs.secrets, message)
            # 14bis)
            res = ldbs.sam.search(expression="(samaccountname=dns)",
                        scope=SCOPE_SUBTREE, attrs=["dn"],
                        controls=["search_options:1:2"])

            if (len(res) == 1):
                ldbs.sam.delete(res[0]["dn"])
                res2 = ldbs.secrets.search(expression="(samaccountname=dns)",
                        scope=SCOPE_SUBTREE, attrs=["dn"])
                update_dns_account_password(ldbs.sam, ldbs.secrets, names)
                message(SIMPLE, "IMPORTANT!!! "
                        "If you were using Dynamic DNS before you need "
                        "to update your configuration, so that the "
                        "tkey-gssapi-credential has the following value: "
                        "DNS/%s.%s" % (names.netbiosname.lower(),
                            names.realm.lower()))
            # 15)
            message(SIMPLE, "Update machine account")
            update_machine_account_password(ldbs.sam, ldbs.secrets, names)

            dnToRecalculate.sort(dn_sort)
            # 16) SD should be created with admin but as some previous acl were so wrong
            # that admin can't modify them we have first to recreate them with the good
            # form but with system account and then give the ownership to admin ...
            if str(oem) != "" and not re.match(r'.*alpha(9|\d\d+)', str(oem)):
                message(SIMPLE, "Fixing very old provision SD")
                rebuild_sd(ldbs.sam, names)

            # We calculate the max USN before recalculating the SD because we might
            # touch object that have been modified after a provision and we do not
            # want that the next upgradeprovision thinks that it has a green light
            # to modify them

            # 17)
            maxUSN = get_max_usn(ldbs.sam, str(names.rootdn))

            # 18) We rebuild SD if a we have a list of DN to recalculate or if the
            # defSDmodified is set.
            if defSDmodified or len(dnToRecalculate) >0:
                message(SIMPLE, "Some (default) security descriptors (SDs) have "
                                "changed, recalculating them")
                ldbs.sam.set_session_info(adm_session)
                rebuild_sd(ldbs.sam, names)

            # 19)
            # Now we are quite confident in the recalculate process of the SD, we make
            # it optional. And we don't do it if there is DN that we must touch
            # as we are assured that on this DNs we will have differences !
            # Also the check must be done in a clever way as for the moment we just
            # compare SDDL
            if len(dnNotToRecalculate) == 0 and (opts.debugchangesd or opts.debugall):
                message(CHANGESD, "Checking recalculated SDs")
                check_updated_sd(new_ldbs.sam, ldbs.sam, names)

            # 20)
            updateOEMInfo(ldbs.sam, str(names.rootdn))
            # 21)
            check_for_DNS(newpaths.private_dir, paths.private_dir)
            # 22)
            if lastProvisionUSNs is not None:
                update_provision_usn(ldbs.sam, minUSN, maxUSN, names.invocation)
            if opts.full and (names.policyid is None or names.policyid_dc is None):
                update_policyids(names, ldbs.sam)
        if opts.nontaclfix:
            if opts.full or opts.resetfileacl or opts.fixntacl:
                try:
                    update_gpo(paths, ldbs.sam, names, lp, message, 1)
                except ProvisioningError, e:
                    message(ERROR, "The policy for domain controller is missing. "
                                "You should restart upgradeprovision with --full")
                except IOError, e:
                    message(ERROR, "Setting ACL not supported on your filesystem")
            else:
                try:
                    update_gpo(paths, ldbs.sam, names, lp, message, 0)
                except ProvisioningError, e:
                    message(ERROR, "The policy for domain controller is missing. "
                                "You should restart upgradeprovision with --full")
        if not opts.fixntacl:
            ldbs.groupedCommit()
            new_ldbs.groupedCommit()
            message(SIMPLE, "Upgrade finished!")
            # remove reference provision now that everything is done !
            # So we have reindexed first if need when the merged schema was reloaded
            # (as new attributes could have quick in)
            # But the second part of the update (when we update existing objects
            # can also have an influence on indexing as some attribute might have their
            # searchflag modificated
            message(SIMPLE, "Reopening samdb to trigger reindexing if needed "
                    "after modification")
            samdb = Ldb(paths.samdb, session_info=session, credentials=creds, lp=lp)
            message(SIMPLE, "Reindexing finished")

            shutil.rmtree(provisiondir)
        else:
            ldbs.groupedRollback()
            message(SIMPLE, "ACLs fixed !")
    except StandardError, err:
        message(ERROR, "A problem occurred while trying to upgrade your "
                   "provision. A full backup is located at %s" % backupdir)
        if opts.debugall or opts.debugchange:
            (typ, val, tb) = sys.exc_info()
            traceback.print_exception(typ, val, tb)
        sys.exit(1)