how do i ldap authenticate with ldap3 and ssl, without a cert?

Question

I would like to authenticate a user with LDAPS.

So my first try was to do that in LDAP:

import os
import socket
import sys
sys.path.append('C:\\Users\\User\\Python\\modules\\')
sys.path.append('C:\\Users\\User\\Python\\modules\\ldap3-2.9.1\\')
import pyasn1

from ldap3 import Server, Connection, SUBTREE, LEVEL, ALL

server = Server('ldapip', get_info='ALL')
con=Connection(server,'aduser','adpassword', auto_bind=True)

BASE_DN = "DC=something,DC=something"

login2b = 'mylogin'
password2 = 'mypassword'

login = login2b
con.search (BASE_DN, '(&(mailNickname='+login+'))', attributes=['*'])
user_dn = str(con.entries[0]['cn'])
print('Login : ',login)
print('user_dn : ',user_dn)

if not con.rebind(user=user_dn, password=password2):
    print('error in rebind', con.result)
else:
    print('user authentificated', con.result)

That worked, but i cant get the SSL Version working.

Thats my code so far:

import os
import socket
import sys
sys.path.append('C:\\Users\\User\\Python\\modules\\')
sys.path.append('C:\\Users\\User\\Python\\modules\\ldap3-2.9.1\\')
import pyasn1
import ssl

from ldap3 import Server, Connection, Tls, SUBTREE, LEVEL, ALL

tls_configuration = Tls(validate=ssl.CERT_NONE, version=ssl.PROTOCOL_TLSv1_2)
server = Server('ldapip:636', use_ssl=True, tls=tls_configuration)
con=Connection(server,'aduser','adpassword', auto_bind=True)

BASE_DN = "DC=something,DC=something"
login5 = 'mylogin'
password5 = 'mypassword'

login = login5
con.search (BASE_DN, '(&(mailNickname='+login+'))', attributes=['*'])
user_dn = str(con.entries[0]['cn'])

if not con.rebind(user=user_dn, password=password5):
    print('error in rebind', con.result)
else:
    print('user authentificated', con.result)

The Error i get:

======= RESTART: C:\Users\User\Python\pyproj\project1\ldapsminimal.py ======
Traceback (most recent call last):
  File "C:\Users\User\Python\pyproj\project1\ldapsminimal.py", line 13, in <module>
    con=Connection(server,'adreadonly','alsach57', auto_bind=True)
  File "C:\Users\User\Python\modules\ldap3-2.9.1\ldap3\core\connection.py", line 363, in __init__
    self._do_auto_bind()
  File "C:\Users\User\Python\modules\ldap3-2.9.1\ldap3\core\connection.py", line 387, in _do_auto_bind
    self.open(read_server_info=False)
  File "C:\Users\User\Python\modules\ldap3-2.9.1\ldap3\strategy\sync.py", line 57, in open
    BaseStrategy.open(self, reset_usage, read_server_info)
  File "C:\Users\User\Python\modules\ldap3-2.9.1\ldap3\strategy\base.py", line 146, in open
    raise exception_history[0][0]
ldap3.core.exceptions.LDAPSocketOpenError: socket ssl wrapping error: [WinError 10054] Eine vorhandene Verbindung wurde vom Remotehost geschlossen

As far as i understand the change is only the server configuration incl. the tls configuration.

• I use validate=ssl.CERT_NONE because i dont want/need to use a cert.
• I use version=ssl.PROTOCOL_TLSv1_2 because i dont know which protocol the ldap is using.

I would like to know what i am doing wrong and a little push in the right direction...

Update: actual code:

import os
import socket
import sys
sys.path.append('C:\\Users\\User\\Python\\modules\\')
sys.path.append('C:\\Users\\User\\Python\\modules\\ldap3-2.9.1\\')
import pyasn1
import ssl

from ldap3 import Server, Connection, SAFE_SYNC, Tls, NTLM, SUBTREE, LEVEL, ALL



authuser = userdn
authpassword = userpassword
aduser = aduser
adpassword = adpassword

BASE_DN = "DC=Something,DC=Something"
t = Tls(validate=ssl.CERT_NONE)
server = Server(host='ldapip', port=636, use_ssl = True, tls=t, get_info='ALL')
con = Connection(server, user=aduser, password=adpassword, client_strategy=SAFE_SYNC , auto_bind='NONE', version=3, authentication='SIMPLE')
#con.bind()
con.unbind()

If i bind(), rebind() or open()i get : ldap3.core.exceptions.LDAPSocketOpenError: socket ssl wrapping error: [WinError 10054] And the connection was closed.