JezK
Edit File: pso.py
# # Helper classes for testing Password Settings Objects. # # This also tests the default password complexity (i.e. pwdProperties), # minPwdLength, pwdHistoryLength settings as a side-effect. # # Copyright (C) Andrew Bartlett <abartlet@samba.org> 2018 # # 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 ldb from ldb import FLAG_MOD_DELETE, FLAG_MOD_ADD, FLAG_MOD_REPLACE from samba.dcerpc.samr import (DOMAIN_PASSWORD_COMPLEX, DOMAIN_PASSWORD_STORE_CLEARTEXT) class TestUser: def __init__(self, username, samdb, userou=None): initial_password = "Initial12#" self.name = username self.ldb = samdb self.dn = "CN=%s,%s,%s" % (username, (userou or "CN=Users"), self.ldb.domain_dn()) # store all passwords that have ever been used for this user, as well # as a pwd_history that more closely resembles the history on the DC self.all_old_passwords = [initial_password] self.pwd_history = [initial_password] self.ldb.newuser(username, initial_password, userou=userou) self.ldb.enable_account("(sAMAccountName=%s)" % username) self.last_pso = None def old_invalid_passwords(self, hist_len): """Returns the expected password history for the DC""" if hist_len == 0: return [] # return the last n items in the list return self.pwd_history[-hist_len:] def old_valid_passwords(self, hist_len): """Returns old passwords that fall outside the DC's expected history""" # if PasswordHistoryLength is zero, any previous password can be valid if hist_len == 0: return self.all_old_passwords[:] # just exclude our pwd_history if there's not much in it. This can # happen if we've been using a lower PasswordHistoryLength setting # previously hist_len = min(len(self.pwd_history), hist_len) # return any passwords up to the nth-from-last item return self.all_old_passwords[:-hist_len] def update_pwd_history(self, new_password): """Updates the user's password history to reflect a password change""" # we maintain 2 lists: all passwords the user has ever had, and an # effective password-history that should roughly mirror the DC. # pwd_history_change() handles the corner-case where we need to # truncate password-history due to PasswordHistoryLength settings # changes if new_password in self.all_old_passwords: self.all_old_passwords.remove(new_password) self.all_old_passwords.append(new_password) if new_password in self.pwd_history: self.pwd_history.remove(new_password) self.pwd_history.append(new_password) def get_resultant_PSO(self): """Returns the DN of the applicable PSO, or None if none applies""" res = self.ldb.search(self.dn, attrs=['msDS-ResultantPSO']) if 'msDS-ResultantPSO' in res[0]: return str(res[0]['msDS-ResultantPSO'][0]) else: return None def get_password(self): """Returns the user's current password""" # current password in the last item in the list return self.all_old_passwords[-1] def set_password(self, new_password): """Attempts to change a user's password""" ldif = """ dn: %s changetype: modify delete: userPassword userPassword: %s add: userPassword userPassword: %s """ % (self.dn, self.get_password(), new_password) # this modify will throw an exception if new_password doesn't meet the # PSO constraints (which the test code catches if it's expected to # fail) self.ldb.modify_ldif(ldif) self.update_pwd_history(new_password) def pwd_history_change(self, old_hist_len, new_hist_len): """ Updates the effective password history, to reflect changes on the DC. When the PasswordHistoryLength applied to a user changes from a low setting (e.g. 2) to a higher setting (e.g. 4), passwords #3 and #4 won't actually have been stored on the DC, so we need to make sure they are removed them from our mirror pwd_history list. """ # our list may have been tracking more passwords than the DC actually # stores. Truncate the list now to match what the DC currently has hist_len = min(new_hist_len, old_hist_len) if hist_len == 0: self.pwd_history = [] elif hist_len < len(self.pwd_history): self.pwd_history = self.pwd_history[-hist_len:] # corner-case where history-length goes from zero to non-zero. Windows # counts the current password as being in the history even before it # changes (Samba only counts it from the next change onwards). We don't # exercise this in the PSO tests due to this discrepancy, but the # following check will support the Windows behaviour if old_hist_len == 0 and new_hist_len > 0: self.pwd_history = [self.get_password()] def set_primary_group(self, group_dn): """Sets a user's primaryGroupID to be that of the specified group""" # get the primaryGroupToken of the group res = self.ldb.search(base=group_dn, attrs=["primaryGroupToken"], scope=ldb.SCOPE_BASE) group_id = res[0]["primaryGroupToken"] # set primaryGroupID attribute of the user to that group m = ldb.Message() m.dn = ldb.Dn(self.ldb, self.dn) m["primaryGroupID"] = ldb.MessageElement(group_id, FLAG_MOD_REPLACE, "primaryGroupID") self.ldb.modify(m) class PasswordSettings: def default_settings(self, samdb): """ Returns a object representing the default password settings that will take effect (i.e. when no other Fine-Grained Password Policy applies) """ pw_attrs = ["minPwdAge", "lockoutDuration", "lockOutObservationWindow", "lockoutThreshold", "maxPwdAge", "minPwdAge", "minPwdLength", "pwdHistoryLength", "pwdProperties"] res = samdb.search(samdb.domain_dn(), scope=ldb.SCOPE_BASE, attrs=pw_attrs) self.name = "Defaults" self.dn = None self.ldb = samdb self.precedence = 0 self.complexity = \ int(res[0]["pwdProperties"][0]) & DOMAIN_PASSWORD_COMPLEX self.store_plaintext = \ int(res[0]["pwdProperties"][0]) & DOMAIN_PASSWORD_STORE_CLEARTEXT self.password_len = int(res[0]["minPwdLength"][0]) self.lockout_attempts = int(res[0]["lockoutThreshold"][0]) self.history_len = int(res[0]["pwdHistoryLength"][0]) # convert to time in secs self.lockout_duration = int(res[0]["lockoutDuration"][0]) / -int(1e7) self.lockout_window =\ int(res[0]["lockOutObservationWindow"][0]) / -int(1e7) self.password_age_min = int(res[0]["minPwdAge"][0]) / -int(1e7) self.password_age_max = int(res[0]["maxPwdAge"][0]) / -int(1e7) def __init__(self, name, samdb, precedence=10, complexity=True, password_len=10, lockout_attempts=0, lockout_duration=5, password_age_min=0, password_age_max=60 * 60 * 24 * 30, history_len=2, store_plaintext=False, container=None): # if no PSO was specified, return an object representing the global # password settings (i.e. the default settings, if no PSO trumps them) if name is None: return self.default_settings(samdb) # only PSOs in the Password Settings Container are considered. You can # create PSOs outside of this container, but it's not recommended if container is None: base_dn = samdb.domain_dn() container = "CN=Password Settings Container,CN=System,%s" % base_dn self.name = name self.dn = "CN=%s,%s" % (name, container) self.ldb = samdb self.precedence = precedence self.complexity = complexity self.store_plaintext = store_plaintext self.password_len = password_len self.lockout_attempts = lockout_attempts self.history_len = history_len # times in secs self.lockout_duration = lockout_duration # lockout observation-window must be <= lockout-duration (the existing # lockout tests just use the same value for both settings) self.lockout_window = lockout_duration self.password_age_min = password_age_min self.password_age_max = password_age_max # add the PSO to the DB self.ldb.add_ldif(self.get_ldif()) def get_ldif(self): complexity_str = "TRUE" if self.complexity else "FALSE" plaintext_str = "TRUE" if self.store_plaintext else "FALSE" # timestamps here are in units of -100 nano-seconds lockout_duration = -int(self.lockout_duration * (1e7)) lockout_window = -int(self.lockout_window * (1e7)) min_age = -int(self.password_age_min * (1e7)) max_age = -int(self.password_age_max * (1e7)) # all the following fields are mandatory for the PSO object ldif = """ dn: {0} objectClass: msDS-PasswordSettings msDS-PasswordSettingsPrecedence: {1} msDS-PasswordReversibleEncryptionEnabled: {2} msDS-PasswordHistoryLength: {3} msDS-PasswordComplexityEnabled: {4} msDS-MinimumPasswordLength: {5} msDS-MinimumPasswordAge: {6} msDS-MaximumPasswordAge: {7} msDS-LockoutThreshold: {8} msDS-LockoutObservationWindow: {9} msDS-LockoutDuration: {10} """.format(self.dn, self.precedence, plaintext_str, self.history_len, complexity_str, self.password_len, min_age, max_age, self.lockout_attempts, lockout_window, lockout_duration) return ldif def apply_to(self, user_group, operation=FLAG_MOD_ADD): """Updates this Password Settings Object to apply to a user or group""" m = ldb.Message() m.dn = ldb.Dn(self.ldb, self.dn) m["msDS-PSOAppliesTo"] = ldb.MessageElement(user_group, operation, "msDS-PSOAppliesTo") self.ldb.modify(m) def unapply(self, user_group): """Updates this PSO to no longer apply to a user or group""" # just delete the msDS-PSOAppliesTo attribute (instead of adding it) self.apply_to(user_group, operation=FLAG_MOD_DELETE) def set_precedence(self, new_precedence, samdb=None): if samdb is None: samdb = self.ldb ldif = """ dn: %s changetype: modify replace: msDS-PasswordSettingsPrecedence msDS-PasswordSettingsPrecedence: %u """ % (self.dn, new_precedence) samdb.modify_ldif(ldif) self.precedence = new_precedence