freeipa/ipatests/test_cmdline/test_ipagetkeytab.py
Christian Heimes 53e0b2255d ipa-getkeytab: resolve symlink
Resolve one level of symbolic links to support a dangling symlink as
keytab target. To prevent symlink attacks, only resolve symlink when the
symlink is owned by the current effective user and group, or by root.

Fixes: https://pagure.io/freeipa/issue/4607
Signed-off-by: Christian Heimes <cheimes@redhat.com>
Reviewed-By: Rob Crittenden <rcritten@redhat.com>
Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>
2019-01-30 08:06:02 +01:00

345 lines
10 KiB
Python

# Authors:
# Rob Crittenden <rcritten@redhat.com>
#
# Copyright (C) 2010 Red Hat
# see file 'COPYING' for use and warranty information
#
# 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/>.
"""
Test `ipa-getkeytab`
"""
from __future__ import absolute_import
import os
import shutil
import tempfile
import gssapi
import pytest
from ipalib import api
from ipaplatform.paths import paths
from ipapython import ipautil, ipaldap
from ipaserver.plugins.ldap2 import ldap2
from ipatests.test_cmdline.cmdline import cmdline_test
from ipatests.test_xmlrpc.tracker import host_plugin, service_plugin
def use_keytab(principal, keytab):
try:
tmpdir = tempfile.mkdtemp(prefix = "tmp-")
ccache_file = 'FILE:%s/ccache' % tmpdir
name = gssapi.Name(principal, gssapi.NameType.kerberos_principal)
store = {'ccache': ccache_file,
'client_keytab': keytab}
os.environ['KRB5CCNAME'] = ccache_file
gssapi.Credentials(name=name, usage='initiate', store=store)
conn = ldap2(api)
conn.connect(autobind=ipaldap.AUTOBIND_DISABLED)
conn.disconnect()
except gssapi.exceptions.GSSError as e:
raise Exception('Unable to bind to LDAP. Error initializing principal %s in %s: %s' % (principal, keytab, str(e)))
finally:
os.environ.pop('KRB5CCNAME', None)
if tmpdir:
shutil.rmtree(tmpdir)
@pytest.fixture(scope='class')
def test_host(request):
host_tracker = host_plugin.HostTracker(u'test-host')
return host_tracker.make_fixture(request)
@pytest.fixture(scope='class')
def test_service(request, test_host):
service_tracker = service_plugin.ServiceTracker(u'srv', test_host.name)
test_host.ensure_exists()
return service_tracker.make_fixture(request)
@pytest.mark.needs_ipaapi
class KeytabRetrievalTest(cmdline_test):
"""
Base class for keytab retrieval tests
"""
command = "ipa-getkeytab"
keytabname = None
@classmethod
def setup_class(cls):
super(KeytabRetrievalTest, cls).setup_class()
keytabfd, keytabname = tempfile.mkstemp()
os.close(keytabfd)
os.unlink(keytabname)
cls.keytabname = keytabname
@classmethod
def teardown_class(cls):
super(KeytabRetrievalTest, cls).teardown_class()
try:
os.unlink(cls.keytabname)
except OSError:
pass
def run_ipagetkeytab(self, service_principal, args=tuple(),
raiseonerr=False):
new_args = [self.command,
"-p", service_principal,
"-k", self.keytabname]
if not args:
new_args.extend(['-s', api.env.host])
else:
new_args.extend(list(args))
return ipautil.run(
new_args,
stdin=None,
raiseonerr=raiseonerr,
capture_error=True)
def assert_success(self, *args, **kwargs):
result = self.run_ipagetkeytab(*args, **kwargs)
expected = 'Keytab successfully retrieved and stored in: %s\n' % (
self.keytabname)
assert expected in result.error_output, (
'Success message not in output:\n%s' % result.error_output)
def assert_failure(self, retcode, message, *args, **kwargs):
result = self.run_ipagetkeytab(*args, **kwargs)
err = result.error_output
assert message in err
rc = result.returncode
assert rc == retcode
@pytest.mark.tier0
class test_ipagetkeytab(KeytabRetrievalTest):
"""
Test `ipa-getkeytab`.
"""
command = "ipa-getkeytab"
keytabname = None
def test_1_run(self, test_service):
"""
Create a keytab with `ipa-getkeytab` for a non-existent service.
"""
test_service.ensure_missing()
result = self.run_ipagetkeytab(test_service.name)
err = result.error_output
assert 'Failed to parse result: PrincipalName not found.\n' in err, err
rc = result.returncode
assert rc > 0, rc
def test_2_run(self, test_service):
"""
Create a keytab with `ipa-getkeytab` for an existing service.
"""
test_service.ensure_exists()
self.assert_success(test_service.name, raiseonerr=True)
def test_3_use(self, test_service):
"""
Try to use the service keytab.
"""
use_keytab(test_service.name, self.keytabname)
def test_4_disable(self, test_service):
"""
Disable a kerberos principal
"""
retrieve_cmd = test_service.make_retrieve_command()
result = retrieve_cmd()
# Verify that it has a principal key
assert result[u'result'][u'has_keytab']
# Disable it
disable_cmd = test_service.make_disable_command()
disable_cmd()
# Verify that it looks disabled
result = retrieve_cmd()
assert not result[u'result'][u'has_keytab']
def test_5_use_disabled(self, test_service):
"""
Try to use the disabled keytab
"""
try:
use_keytab(test_service.name, self.keytabname)
except Exception as errmsg:
assert('Unable to bind to LDAP. Error initializing principal' in str(errmsg))
def test_dangling_symlink(self, test_service):
# see https://pagure.io/freeipa/issue/4607
test_service.ensure_exists()
fd, symlink_target = tempfile.mkstemp()
os.close(fd)
os.unlink(symlink_target)
# create dangling symlink
os.symlink(self.keytabname, symlink_target)
try:
self.assert_success(test_service.name, raiseonerr=True)
assert os.path.isfile(symlink_target)
assert os.path.samefile(self.keytabname, symlink_target)
finally:
os.unlink(symlink_target)
class TestBindMethods(KeytabRetrievalTest):
"""
Class that tests '-c'/'-H'/'-Y' flags
"""
dm_password = None
ca_cert = None
@classmethod
def setup_class(cls):
super(TestBindMethods, cls).setup_class()
dmpw_file = os.path.join(api.env.dot_ipa, '.dmpw')
if not os.path.isfile(dmpw_file):
pytest.skip('{} file required for this test'.format(dmpw_file))
with open(dmpw_file, 'r') as f:
cls.dm_password = f.read().strip()
tempfd, temp_ca_cert = tempfile.mkstemp()
os.close(tempfd)
shutil.copy(os.path.join(paths.IPA_CA_CRT), temp_ca_cert)
cls.ca_cert = temp_ca_cert
@classmethod
def teardown_class(cls):
super(TestBindMethods, cls).teardown_class()
try:
os.unlink(cls.ca_cert)
except OSError:
pass
def check_ldapi(self):
if not api.env.ldap_uri.startswith('ldapi://'):
pytest.skip("LDAP URI not pointing to LDAPI socket")
def test_retrieval_with_dm_creds(self, test_service):
test_service.ensure_exists()
self.assert_success(
test_service.name,
args=[
'-D', "cn=Directory Manager",
'-w', self.dm_password,
'-s', api.env.host])
def test_retrieval_using_plain_ldap(self, test_service):
test_service.ensure_exists()
ldap_uri = 'ldap://{}'.format(api.env.host)
self.assert_success(
test_service.name,
args=[
'-D', "cn=Directory Manager",
'-w', self.dm_password,
'-H', ldap_uri])
@pytest.mark.skipif(os.geteuid() != 0,
reason="Must have root privileges to run this test")
def test_retrieval_using_ldapi_external(self, test_service):
test_service.ensure_exists()
self.check_ldapi()
self.assert_success(
test_service.name,
args=[
'-Y',
'EXTERNAL',
'-H', api.env.ldap_uri])
def test_retrieval_using_ldap_gssapi(self, test_service):
test_service.ensure_exists()
self.check_ldapi()
self.assert_success(
test_service.name,
args=[
'-Y',
'GSSAPI',
'-H', api.env.ldap_uri])
def test_retrieval_using_ldaps_ca_cert(self, test_service):
test_service.ensure_exists()
self.assert_success(
test_service.name,
args=[
'-D', "cn=Directory Manager",
'-w', self.dm_password,
'-H', 'ldaps://{}'.format(api.env.host),
'--cacert', self.ca_cert])
def test_ldap_uri_server_raises_error(self, test_service):
test_service.ensure_exists()
self.assert_failure(
2,
"Cannot specify server and LDAP uri simultaneously",
test_service.name,
args=[
'-H', 'ldaps://{}'.format(api.env.host),
'-s', api.env.host],
raiseonerr=False)
def test_invalid_mech_raises_error(self, test_service):
test_service.ensure_exists()
self.assert_failure(
2,
"Invalid SASL bind mechanism",
test_service.name,
args=[
'-H', 'ldaps://{}'.format(api.env.host),
'-Y', 'BOGUS'],
raiseonerr=False)
def test_mech_bind_dn_raises_error(self, test_service):
test_service.ensure_exists()
self.assert_failure(
2,
"Cannot specify both SASL mechanism and bind DN simultaneously",
test_service.name,
args=[
'-D', "cn=Directory Manager",
'-w', self.dm_password,
'-H', 'ldaps://{}'.format(api.env.host),
'-Y', 'EXTERNAL'],
raiseonerr=False)