freeipa/ipaserver/install/krbinstance.py
2025-08-12 22:28:56 +02:00

670 lines
25 KiB
Python

# Authors: Simo Sorce <ssorce@redhat.com>
#
# Copyright (C) 2007 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/>.
#
from __future__ import absolute_import
from __future__ import print_function
import logging
import os
import socket
import dbus
import dns.name
from pkg_resources import parse_version
from ipalib import x509
from ipalib.install import certstore
from ipaserver.install import service
from ipaserver.install import installutils
from ipapython import ipaldap
from ipapython import ipautil
from ipapython import kernel_keyring
from ipapython.version import KRB5_BUILD_VERSION
from ipalib import api, errors
from ipalib.constants import ANON_USER
from ipalib.install import certmonger
from ipapython.dn import DN
from ipapython.dogtag import KDC_PROFILE
from ipaserver.install import replication
from ipaserver.install import certs
from ipaserver.masters import (
find_providing_servers,
PAC_TKT_SIGN_SUPPORTED,
PKINIT_ENABLED,
)
from ipaplatform.constants import constants
from ipaplatform.tasks import tasks
from ipaplatform.paths import paths
logger = logging.getLogger(__name__)
MASTER_KEY_TYPE = 'aes256-sha2'
SUPPORTED_ENCTYPES = ('aes256-sha2:special', 'aes128-sha2:special',
'aes256-sha2:normal', 'aes128-sha2:normal',
'aes256-cts:special', 'aes128-cts:special',
'aes256-cts:normal', 'aes128-cts:normal',
'camellia256-cts:special', 'camellia128-cts:special',
'camellia256-cts:normal', 'camellia128-cts:normal')
def get_pkinit_request_ca():
"""
Return the certmonger CA name which is serving the PKINIT certificate
request. If the certificate is not tracked by Certmonger, return None
"""
pkinit_request_id = certmonger.get_request_id(
{'cert-file': paths.KDC_CERT})
if pkinit_request_id is None:
return None
return certmonger.get_request_value(pkinit_request_id, 'ca-name')
def is_pkinit_enabled():
"""
check whether PKINIT is enabled on the master by checking for the presence
of KDC certificate and it's tracking CA
"""
if os.path.exists(paths.KDC_CERT):
pkinit_request_ca = get_pkinit_request_ca()
if pkinit_request_ca and pkinit_request_ca != "SelfSign":
return True
return False
class KpasswdInstance(service.SimpleServiceInstance):
def __init__(self):
service.SimpleServiceInstance.__init__(self, "kadmin")
class KrbInstance(service.Service):
def __init__(self, fstore=None):
super(KrbInstance, self).__init__(
"krb5kdc",
service_desc="Kerberos KDC",
fstore=fstore
)
self.fqdn = None
self.realm = None
self.domain = None
self.host = None
self.admin_password = None
self.master_password = None
self.suffix = None
self.subject_base = None
self.kdc_password = None
self.sub_dict = None
self.pkcs12_info = None
self.master_fqdn = None
self.config_pkinit = None
suffix = ipautil.dn_attribute_property('_suffix')
subject_base = ipautil.dn_attribute_property('_subject_base')
def init_info(self, realm_name, host_name, setup_pkinit=False,
subject_base=None):
self.fqdn = host_name
self.realm = realm_name
self.suffix = ipautil.realm_to_suffix(realm_name)
self.subject_base = subject_base
self.config_pkinit = setup_pkinit
def get_realm_suffix(self):
return DN(('cn', self.realm), ('cn', 'kerberos'), self.suffix)
def move_service_to_host(self, principal):
"""
Used to move a host/ service principal created by kadmin.local from
cn=kerberos to reside under the host entry.
"""
service_dn = DN(('krbprincipalname', principal), self.get_realm_suffix())
service_entry = api.Backend.ldap2.get_entry(service_dn)
api.Backend.ldap2.delete_entry(service_entry)
# Create a host entry for this master
host_dn = DN(
('fqdn', self.fqdn), ('cn', 'computers'), ('cn', 'accounts'),
self.suffix)
host_entry = api.Backend.ldap2.make_entry(
host_dn,
objectclass=[
'top', 'ipaobject', 'nshost', 'ipahost', 'ipaservice',
'pkiuser', 'krbprincipalaux', 'krbprincipal',
'krbticketpolicyaux', 'ipasshhost'],
krbextradata=service_entry['krbextradata'],
krblastpwdchange=service_entry['krblastpwdchange'],
krbprincipalname=service_entry['krbprincipalname'],
krbcanonicalname=service_entry['krbcanonicalname'],
krbprincipalkey=service_entry['krbprincipalkey'],
serverhostname=[self.fqdn.split('.',1)[0]],
cn=[self.fqdn],
fqdn=[self.fqdn],
ipauniqueid=['autogenerate'],
managedby=[host_dn],
)
if 'krbpasswordexpiration' in service_entry:
host_entry['krbpasswordexpiration'] = service_entry[
'krbpasswordexpiration']
if 'krbticketflags' in service_entry:
host_entry['krbticketflags'] = service_entry['krbticketflags']
api.Backend.ldap2.add_entry(host_entry)
# Add the host to the ipaserver host group
self._ldap_update(['20-ipaservers_hostgroup.update'])
def pac_tkt_sign_support_enable(self):
"""
Advertise PAC ticket signature support in master's KDC entry in LDAP
"""
service.set_service_entry_config(
'KDC', self.fqdn, [PAC_TKT_SIGN_SUPPORTED], self.suffix)
def __common_setup(self, realm_name, host_name, domain_name, admin_password):
self.fqdn = host_name
self.realm = realm_name.upper()
self.host = host_name.split(".")[0]
self.ip = socket.getaddrinfo(host_name, None, socket.AF_UNSPEC, socket.SOCK_STREAM)[0][4][0]
self.domain = domain_name
self.suffix = ipautil.realm_to_suffix(self.realm)
self.kdc_password = ipautil.ipa_generate_password()
self.admin_password = admin_password
self.dm_password = admin_password
self.__setup_sub_dict()
self.backup_state("running", self.is_running())
try:
self.stop()
except Exception:
# It could have been not running
pass
def __common_post_setup(self):
self.step("creating anonymous principal", self.add_anonymous_principal)
self.step("starting the KDC", self.__start_instance)
self.step("configuring KDC to start on boot", self.__enable)
def create_instance(self, realm_name, host_name, domain_name, admin_password, master_password, setup_pkinit=False, pkcs12_info=None, subject_base=None):
self.master_password = master_password
self.pkcs12_info = pkcs12_info
self.subject_base = subject_base
self.config_pkinit = setup_pkinit
self.__common_setup(realm_name, host_name, domain_name, admin_password)
self.step("adding kerberos container to the directory", self.__add_krb_container)
self.step("configuring KDC", self.__configure_instance)
self.step("initialize kerberos container", self.__init_ipa_kdb)
self.step("adding default ACIs", self.__add_default_acis)
self.step("creating a keytab for the directory", self.__create_ds_keytab)
self.step("creating a keytab for the machine", self.__create_host_keytab)
self.step("adding the password extension to the directory", self.__add_pwd_extop_module)
self.__common_post_setup()
if KRB5_BUILD_VERSION >= parse_version('1.20'):
self.step("enable PAC ticket signature support",
self.pac_tkt_sign_support_enable)
self.start_creation()
self.kpasswd = KpasswdInstance()
self.kpasswd.create_instance('KPASSWD', self.fqdn, self.suffix,
realm=self.realm)
def create_replica(self, realm_name,
master_fqdn, host_name,
domain_name, admin_password,
setup_pkinit=False, pkcs12_info=None,
subject_base=None):
self.pkcs12_info = pkcs12_info
self.subject_base = subject_base
self.master_fqdn = master_fqdn
self.config_pkinit = setup_pkinit
self.__common_setup(realm_name, host_name, domain_name, admin_password)
self.step("configuring KDC", self.__configure_instance)
self.step("adding the password extension to the directory", self.__add_pwd_extop_module)
self.__common_post_setup()
if KRB5_BUILD_VERSION >= parse_version('1.20'):
self.step("enable PAC ticket signature support",
self.pac_tkt_sign_support_enable)
self.start_creation()
self.kpasswd = KpasswdInstance()
self.kpasswd.create_instance('KPASSWD', self.fqdn, self.suffix)
def __enable(self):
self.backup_state("enabled", self.is_enabled())
# We do not let the system start IPA components on its own,
# Instead we reply on the IPA init script to start only enabled
# components as found in our LDAP configuration tree
self.ldap_configure('KDC', self.fqdn, None, self.suffix)
def __start_instance(self):
try:
self.start()
except Exception:
logger.critical("krb5kdc service failed to start")
def __setup_sub_dict(self):
if os.path.exists(paths.COMMON_KRB5_CONF_DIR):
includes = 'includedir {}'.format(paths.COMMON_KRB5_CONF_DIR)
else:
includes = ''
fips_enabled = tasks.is_fips_enabled()
self.sub_dict = dict(FQDN=self.fqdn,
IP=self.ip,
PASSWORD=self.kdc_password,
SUFFIX=self.suffix,
DOMAIN=self.domain,
HOST=self.host,
SERVER_ID=ipaldap.realm_to_serverid(self.realm),
REALM=self.realm,
KRB5KDC_KADM5_ACL=paths.KRB5KDC_KADM5_ACL,
DICT_WORDS=paths.DICT_WORDS,
KRB5KDC_KADM5_KEYTAB=paths.KRB5KDC_KADM5_KEYTAB,
KDC_CERT=paths.KDC_CERT,
KDC_KEY=paths.KDC_KEY,
CACERT_PEM=paths.CACERT_PEM,
KDC_CA_BUNDLE_PEM=paths.KDC_CA_BUNDLE_PEM,
CA_BUNDLE_PEM=paths.CA_BUNDLE_PEM,
INCLUDES=includes,
FIPS='#' if fips_enabled else '')
if fips_enabled:
supported_enctypes = list(
filter(lambda e: not e.startswith('camellia'),
SUPPORTED_ENCTYPES))
else:
supported_enctypes = SUPPORTED_ENCTYPES
self.sub_dict['SUPPORTED_ENCTYPES'] = ' '.join(supported_enctypes)
self.sub_dict['MASTER_KEY_TYPE'] = MASTER_KEY_TYPE
# IPA server/KDC is not a subdomain of default domain
# Proper domain-realm mapping needs to be specified
domain = dns.name.from_text(self.domain)
fqdn = dns.name.from_text(self.fqdn)
if not fqdn.is_subdomain(domain):
logger.debug("IPA FQDN '%s' is not located in default domain '%s'",
fqdn, domain)
server_domain = fqdn.parent().to_unicode(omit_final_dot=True)
logger.debug("Domain '%s' needs additional mapping in krb5.conf",
server_domain)
dr_map = " .%(domain)s = %(realm)s\n %(domain)s = %(realm)s\n" \
% dict(domain=server_domain, realm=self.realm)
else:
dr_map = ""
self.sub_dict['OTHER_DOMAIN_REALM_MAPS'] = dr_map
# Configure KEYRING CCACHE if supported
if kernel_keyring.is_persistent_keyring_supported():
logger.debug("Enabling persistent keyring CCACHE")
self.sub_dict['OTHER_LIBDEFAULTS'] = \
" default_ccache_name = KEYRING:persistent:%{uid}\n"
else:
logger.debug("Persistent keyring CCACHE is not enabled")
self.sub_dict['OTHER_LIBDEFAULTS'] = ''
# Create kadm5.acl if it doesn't exist
if not os.path.exists(paths.KRB5KDC_KADM5_ACL):
open(paths.KRB5KDC_KADM5_ACL, 'a').close()
os.chmod(paths.KRB5KDC_KADM5_ACL, 0o600)
def __add_krb_container(self):
self._ldap_mod("kerberos.ldif", self.sub_dict)
def __add_default_acis(self):
self._ldap_mod("default-aci.ldif", self.sub_dict)
def __template_file(self, path, chmod=0o644, client_template=False):
if client_template:
sharedir = paths.USR_SHARE_IPA_CLIENT_DIR
else:
sharedir = paths.USR_SHARE_IPA_DIR
template = os.path.join(
sharedir, os.path.basename(path) + ".template")
conf = ipautil.template_file(template, self.sub_dict)
self.fstore.backup_file(path)
with open(path, 'w') as f:
if chmod is not None:
os.fchmod(f.fileno(), chmod)
f.write(conf)
def __init_ipa_kdb(self):
# kdb5_util may take a very long time when entropy is low
installutils.check_entropy()
#populate the directory with the realm structure
args = ["kdb5_util", "create", "-s",
"-r", self.realm,
"-x", "ipa-setup-override-restrictions"]
dialogue = (
# Enter KDC database master key:
self.master_password + '\n',
# Re-enter KDC database master key to verify:
self.master_password + '\n',
)
try:
ipautil.run(args, nolog=(self.master_password,), stdin=''.join(dialogue))
except ipautil.CalledProcessError as error:
logger.debug("kdb5_util failed with %s", error)
raise RuntimeError("Failed to initialize kerberos container")
def __configure_instance(self):
self.__template_file(paths.KRB5KDC_KDC_CONF, chmod=None)
self.__template_file(paths.KRB5_CONF)
self.__template_file(paths.KRB5_FREEIPA_SERVER)
self.__template_file(paths.KRB5_FREEIPA, client_template=True)
self.__template_file(paths.HTML_KRB5_INI)
self.__template_file(paths.KRB_CON)
self.__template_file(paths.HTML_KRBREALM_CON)
MIN_KRB5KDC_WITH_WORKERS = "1.9"
cpus = os.sysconf('SC_NPROCESSORS_ONLN')
workers = False
result = ipautil.run([paths.KLIST, '-V'],
raiseonerr=False, capture_output=True)
if result.returncode == 0:
verstr = result.output.split()[-1]
ver = tasks.parse_ipa_version(verstr)
min = tasks.parse_ipa_version(MIN_KRB5KDC_WITH_WORKERS)
if ver >= min:
workers = True
# Write down config file
# We write realm and also number of workers (for multi-CPU systems)
replacevars = {'KRB5REALM':self.realm}
appendvars = {}
if workers and cpus > 1:
appendvars = {'KRB5KDC_ARGS': "'-w %s'" % str(cpus)}
ipautil.backup_config_and_replace_variables(self.fstore, paths.SYSCONFIG_KRB5KDC_DIR,
replacevars=replacevars,
appendvars=appendvars)
tasks.restore_context(paths.SYSCONFIG_KRB5KDC_DIR)
#add the password extop module
def __add_pwd_extop_module(self):
self._ldap_mod("pwd-extop-conf.ldif", self.sub_dict)
def __create_ds_keytab(self):
ldap_principal = "ldap/" + self.fqdn + "@" + self.realm
installutils.kadmin_addprinc(ldap_principal)
self.move_service(ldap_principal)
self.fstore.backup_file(paths.DS_KEYTAB)
installutils.create_keytab(paths.DS_KEYTAB, ldap_principal)
constants.DS_USER.chown(paths.DS_KEYTAB)
def __create_host_keytab(self):
host_principal = "host/" + self.fqdn + "@" + self.realm
installutils.kadmin_addprinc(host_principal)
self.fstore.backup_file(paths.KRB5_KEYTAB)
installutils.create_keytab(paths.KRB5_KEYTAB, host_principal)
# Make sure access is strictly reserved to root only for now
os.chown(paths.KRB5_KEYTAB, 0, 0)
os.chmod(paths.KRB5_KEYTAB, 0o600)
self.move_service_to_host(host_principal)
def _wait_for_replica_kdc_entry(self):
master_dn = self.api.Object.server.get_dn(self.fqdn)
kdc_dn = DN(('cn', 'KDC'), master_dn)
ldap_uri = ipaldap.get_ldap_uri(self.master_fqdn)
with ipaldap.LDAPClient(
ldap_uri, cacert=paths.IPA_CA_CRT, start_tls=True
) as remote_ldap:
remote_ldap.gssapi_bind()
replication.wait_for_entry(
remote_ldap,
kdc_dn,
timeout=api.env.replication_wait_timeout
)
def _call_certmonger(self, certmonger_ca='IPA'):
subject = str(DN(('cn', self.fqdn), self.subject_base))
krbtgt = "krbtgt/" + self.realm + "@" + self.realm
certpath = (paths.KDC_CERT, paths.KDC_KEY)
prev_helper = None
try:
# on the first CA-ful master without '--no-pkinit', we issue the
# certificate by contacting Dogtag directly
ca_instances = find_providing_servers(
'CA', conn=self.api.Backend.ldap2, api=self.api)
use_dogtag_submit = all(
[self.master_fqdn is None,
self.pkcs12_info is None,
self.config_pkinit,
len(ca_instances) == 0])
if use_dogtag_submit:
ca_args = [
paths.CERTMONGER_DOGTAG_SUBMIT,
'--ee-url', 'https://%s:8443/ca/ee/ca' % self.fqdn,
'--certfile', paths.RA_AGENT_PEM,
'--keyfile', paths.RA_AGENT_KEY,
'--cafile', paths.IPA_CA_CRT,
'--agent-submit'
]
helper = " ".join(ca_args)
prev_helper = certmonger.modify_ca_helper(
certmonger_ca, helper
)
certmonger.request_and_wait_for_cert(
certpath=certpath,
subject=subject,
principal=krbtgt,
ca=certmonger_ca,
dns=[self.fqdn],
storage='FILE',
profile=KDC_PROFILE,
post_command='renew_kdc_cert',
perms=(0o644, 0o600),
resubmit_timeout=api.env.certmonger_wait_timeout
)
except dbus.DBusException as e:
# if the certificate is already tracked, ignore the error
name = e.get_dbus_name()
if name != 'org.fedorahosted.certmonger.duplicate':
logger.error("Failed to initiate the request: %s", e)
return
finally:
if prev_helper is not None:
certmonger.modify_ca_helper(certmonger_ca, prev_helper)
def pkinit_enable(self):
"""
advertise enabled PKINIT feature in master's KDC entry in LDAP
"""
service.set_service_entry_config(
'KDC', self.fqdn, [PKINIT_ENABLED], self.suffix)
def pkinit_disable(self):
"""
unadvertise enabled PKINIT feature in master's KDC entry in LDAP
"""
ldap = api.Backend.ldap2
dn = DN(('cn', 'KDC'), ('cn', self.fqdn), api.env.container_masters,
self.suffix)
entry = ldap.get_entry(dn, ['ipaConfigString'])
config = entry.setdefault('ipaConfigString', [])
config = [value for value in config
if value.lower() != PKINIT_ENABLED.lower()]
entry['ipaConfigString'][:] = config
try:
ldap.update_entry(entry)
except errors.EmptyModlist:
pass
def _install_pkinit_ca_bundle(self):
ca_certs = certstore.get_ca_certs(self.api.Backend.ldap2,
self.api.env.basedn,
self.api.env.realm,
False)
ca_certs = [c for c, _n, t, _u in ca_certs if t is not False]
x509.write_certificate_list(ca_certs, paths.CACERT_PEM, mode=0o644)
def issue_selfsigned_pkinit_certs(self):
self._call_certmonger(certmonger_ca="SelfSign")
with open(paths.CACERT_PEM, 'w'):
pass
def issue_ipa_ca_signed_pkinit_certs(self):
try:
self._call_certmonger()
self._install_pkinit_ca_bundle()
self.pkinit_enable()
except RuntimeError as e:
logger.warning("PKINIT certificate request failed: %s", e)
logger.warning("Failed to configure PKINIT")
self.print_msg("Full PKINIT configuration did not succeed")
self.print_msg(
"The setup will only install bits "
"essential to the server functionality")
self.print_msg(
"You can enable PKINIT after the "
"setup completed using 'ipa-pkinit-manage'")
self.stop_tracking_certs()
self.issue_selfsigned_pkinit_certs()
def install_external_pkinit_certs(self):
certs.install_pem_from_p12(self.pkcs12_info[0],
self.pkcs12_info[1],
paths.KDC_CERT)
# The KDC cert needs to be readable by everyone
os.chmod(paths.KDC_CERT, 0o644)
certs.install_key_from_p12(self.pkcs12_info[0],
self.pkcs12_info[1],
paths.KDC_KEY)
self._install_pkinit_ca_bundle()
self.pkinit_enable()
def setup_pkinit(self):
if self.pkcs12_info:
self.install_external_pkinit_certs()
elif self.config_pkinit:
self.issue_ipa_ca_signed_pkinit_certs()
def enable_ssl(self):
"""
generate PKINIT certificate for KDC. If `--no-pkinit` was specified,
only configure local self-signed KDC certificate for use as a FAST
channel generator for WebUI. Do not advertise the installation steps in
this case.
"""
if self.master_fqdn is not None:
self._wait_for_replica_kdc_entry()
if self.config_pkinit:
self.steps = []
self.step("installing X509 Certificate for PKINIT",
self.setup_pkinit)
self.start_creation()
else:
self.issue_selfsigned_pkinit_certs()
try:
self.restart()
except Exception:
logger.critical("krb5kdc service failed to restart")
raise
def get_anonymous_principal_name(self):
return "%s@%s" % (ANON_USER, self.realm)
def add_anonymous_principal(self):
# Create the special anonymous principal
princ_realm = self.get_anonymous_principal_name()
dn = DN(('krbprincipalname', princ_realm), self.get_realm_suffix())
try:
self.api.Backend.ldap2.get_entry(dn)
except errors.NotFound:
installutils.kadmin_addprinc(princ_realm)
self._ldap_mod("anon-princ-aci.ldif", self.sub_dict)
try:
self.api.Backend.ldap2.set_entry_active(dn, True)
except errors.AlreadyActive:
pass
def stop_tracking_certs(self):
certmonger.stop_tracking(certfile=paths.KDC_CERT)
def delete_pkinit_cert(self):
ipautil.remove_file(paths.KDC_CERT)
ipautil.remove_file(paths.KDC_KEY)
def uninstall(self):
if self.is_configured():
self.print_msg("Unconfiguring %s" % self.service_name)
running = self.restore_state("running")
enabled = self.restore_state("enabled")
try:
self.stop()
except Exception:
pass
for f in [paths.KRB5KDC_KDC_CONF, paths.KRB5_CONF]:
try:
self.fstore.restore_file(f)
except ValueError as error:
logger.debug("%s", error)
# disabled by default, by ldap_configure()
if enabled:
self.enable()
# stop tracking and remove certificates
self.stop_tracking_certs()
ipautil.remove_file(paths.CACERT_PEM)
self.delete_pkinit_cert()
if running:
self.restart()
self.kpasswd = KpasswdInstance()
self.kpasswd.uninstall()
ipautil.remove_file(paths.KRB5_KEYTAB)
ipautil.remove_file(paths.KRB5_FREEIPA)
ipautil.remove_file(paths.KRB5_FREEIPA_SERVER)