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Douglas Bagnall 62cc4302b6 CVE-2023-0225 pytest/acl: test deleting dNSHostName as unprivileged user
BUG: https://bugzilla.samba.org/show_bug.cgi?id=15276

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
2023-04-05 02:10:35 +00:00

237 lines
8.1 KiB
Python
Executable File

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
import optparse
import sys
sys.path.insert(0, "bin/python")
import samba
from samba.tests.subunitrun import SubunitOptions, TestProgram
import samba.getopt as options
from ldb import ERR_INSUFFICIENT_ACCESS_RIGHTS
from ldb import Message, MessageElement, Dn
from ldb import FLAG_MOD_REPLACE, FLAG_MOD_DELETE
from samba.dcerpc import security
from samba.auth import system_session
from samba import gensec, sd_utils
from samba.samdb import SamDB
from samba.credentials import Credentials, DONT_USE_KERBEROS
import samba.tests
import samba.dsdb
parser = optparse.OptionParser("acl.py [options] <host>")
sambaopts = options.SambaOptions(parser)
parser.add_option_group(sambaopts)
parser.add_option_group(options.VersionOptions(parser))
# use command line creds if available
credopts = options.CredentialsOptions(parser)
parser.add_option_group(credopts)
subunitopts = SubunitOptions(parser)
parser.add_option_group(subunitopts)
opts, args = parser.parse_args()
if len(args) < 1:
parser.print_usage()
sys.exit(1)
host = args[0]
if "://" not in host:
ldaphost = "ldap://%s" % host
else:
ldaphost = host
start = host.rindex("://")
host = host.lstrip(start + 3)
lp = sambaopts.get_loadparm()
creds = credopts.get_credentials(lp)
creds.set_gensec_features(creds.get_gensec_features() | gensec.FEATURE_SEAL)
#
# Tests start here
#
class AclTests(samba.tests.TestCase):
def setUp(self):
super(AclTests, self).setUp()
strict_checking = samba.tests.env_get_var_value('STRICT_CHECKING', allow_missing=True)
if strict_checking is None:
strict_checking = '1'
self.strict_checking = bool(int(strict_checking))
self.ldb_admin = SamDB(ldaphost, credentials=creds, session_info=system_session(lp), lp=lp)
self.base_dn = self.ldb_admin.domain_dn()
self.domain_sid = security.dom_sid(self.ldb_admin.get_domain_sid())
self.user_pass = "samba123@"
self.configuration_dn = self.ldb_admin.get_config_basedn().get_linearized()
self.sd_utils = sd_utils.SDUtils(self.ldb_admin)
self.addCleanup(self.delete_admin_connection)
# used for anonymous login
self.creds_tmp = Credentials()
self.creds_tmp.set_username("")
self.creds_tmp.set_password("")
self.creds_tmp.set_domain(creds.get_domain())
self.creds_tmp.set_realm(creds.get_realm())
self.creds_tmp.set_workstation(creds.get_workstation())
print("baseDN: %s" % self.base_dn)
# set AttributeAuthorizationOnLDAPAdd and BlockOwnerImplicitRights
self.set_heuristic(samba.dsdb.DS_HR_ATTR_AUTHZ_ON_LDAP_ADD, b'11')
def set_heuristic(self, index, values):
self.assertGreater(index, 0)
self.assertLess(index, 30)
self.assertIsInstance(values, bytes)
# Get the old "dSHeuristics" if it was set
dsheuristics = self.ldb_admin.get_dsheuristics()
# Reset the "dSHeuristics" as they were before
self.addCleanup(self.ldb_admin.set_dsheuristics, dsheuristics)
# Set the "dSHeuristics" to activate the correct behaviour
default_heuristics = b"000000000100000000020000000003"
if dsheuristics is None:
dsheuristics = b""
dsheuristics += default_heuristics[len(dsheuristics):]
dsheuristics = (dsheuristics[:index - 1] +
values +
dsheuristics[index - 1 + len(values):])
self.ldb_admin.set_dsheuristics(dsheuristics)
def get_user_dn(self, name):
return "CN=%s,CN=Users,%s" % (name, self.base_dn)
def get_ldb_connection(self, target_username, target_password):
creds_tmp = Credentials()
creds_tmp.set_username(target_username)
creds_tmp.set_password(target_password)
creds_tmp.set_domain(creds.get_domain())
creds_tmp.set_realm(creds.get_realm())
creds_tmp.set_workstation(creds.get_workstation())
creds_tmp.set_gensec_features(creds_tmp.get_gensec_features()
| gensec.FEATURE_SEAL)
creds_tmp.set_kerberos_state(DONT_USE_KERBEROS) # kinit is too expensive to use in a tight loop
ldb_target = SamDB(url=ldaphost, credentials=creds_tmp, lp=lp)
return ldb_target
# Test if we have any additional groups for users than default ones
def assert_user_no_group_member(self, username):
res = self.ldb_admin.search(self.base_dn, expression="(distinguishedName=%s)" % self.get_user_dn(username))
try:
self.assertEqual(res[0]["memberOf"][0], "")
except KeyError:
pass
else:
self.fail()
def delete_admin_connection(self):
del self.sd_utils
del self.ldb_admin
class AclModifyTests(AclTests):
def setup_computer_with_hostname(self, account_name):
ou_dn = f'OU={account_name},{self.base_dn}'
dn = f'CN={account_name},{ou_dn}'
user, password = "mouse", "mus musculus 123!"
self.addCleanup(self.ldb_admin.deleteuser, user)
self.ldb_admin.newuser(user, password)
self.ldb_user = self.get_ldb_connection(user, password)
self.addCleanup(self.ldb_admin.delete, ou_dn,
controls=["tree_delete:0"])
self.ldb_admin.create_ou(ou_dn)
self.ldb_admin.add({
'dn': dn,
'objectClass': 'computer',
'sAMAccountName': account_name + '$',
})
host_name = f'{account_name}.{self.ldb_user.domain_dns_name()}'
m = Message(Dn(self.ldb_admin, dn))
m['dNSHostName'] = MessageElement(host_name,
FLAG_MOD_REPLACE,
'dNSHostName')
self.ldb_admin.modify(m)
return host_name, dn
def test_modify_delete_dns_host_name_specified(self):
'''Test deleting dNSHostName'''
account_name = self.id().rsplit(".", 1)[1][:63]
host_name, dn = self.setup_computer_with_hostname(account_name)
m = Message(Dn(self.ldb_user, dn))
m['dNSHostName'] = MessageElement(host_name,
FLAG_MOD_DELETE,
'dNSHostName')
self.assertRaisesLdbError(
ERR_INSUFFICIENT_ACCESS_RIGHTS,
"User able to delete dNSHostName (with specified name)",
self.ldb_user.modify, m)
def test_modify_delete_dns_host_name_unspecified(self):
'''Test deleting dNSHostName'''
account_name = self.id().rsplit(".", 1)[1][:63]
host_name, dn = self.setup_computer_with_hostname(account_name)
m = Message(Dn(self.ldb_user, dn))
m['dNSHostName'] = MessageElement([],
FLAG_MOD_DELETE,
'dNSHostName')
self.assertRaisesLdbError(
ERR_INSUFFICIENT_ACCESS_RIGHTS,
"User able to delete dNSHostName (without specified name)",
self.ldb_user.modify, m)
def test_modify_delete_dns_host_name_ldif_specified(self):
'''Test deleting dNSHostName'''
account_name = self.id().rsplit(".", 1)[1][:63]
host_name, dn = self.setup_computer_with_hostname(account_name)
ldif = f"""
dn: {dn}
changetype: modify
delete: dNSHostName
dNSHostName: {host_name}
"""
self.assertRaisesLdbError(
ERR_INSUFFICIENT_ACCESS_RIGHTS,
"User able to delete dNSHostName (with specified name)",
self.ldb_user.modify_ldif, ldif)
def test_modify_delete_dns_host_name_ldif_unspecified(self):
'''Test deleting dNSHostName'''
account_name = self.id().rsplit(".", 1)[1][:63]
host_name, dn = self.setup_computer_with_hostname(account_name)
ldif = f"""
dn: {dn}
changetype: modify
delete: dNSHostName
"""
self.assertRaisesLdbError(
ERR_INSUFFICIENT_ACCESS_RIGHTS,
"User able to delete dNSHostName (without specific name)",
self.ldb_user.modify_ldif, ldif)
ldb = SamDB(ldaphost, credentials=creds, session_info=system_session(lp), lp=lp)
TestProgram(module=__name__, opts=subunitopts)