freeipa/ipaserver/dnssec/bindmgr.py
François Cami 20f68d817d freeipa.spec: depend on bind-dnssec-utils
The OpenDNSSec integration code requires:
/usr/sbin/dnssec-keyfromlabel-pkcs11
which is provided by bind-pkcs11-utils, but that package is
only available on RHEL<9.

With this change, freeipa-server-dns depends on bind-dnssec-utils
on all Fedora releases and RHEL==9+, and uses:
/usr/sbin/dnssec-keyfromlabel -E pkcs11
instead of dnssec-keyfromlabel-pkcs11.

Fixes: https://pagure.io/freeipa/issue/9026
Signed-off-by: François Cami <fcami@redhat.com>
Reviewed-By: Rob Crittenden <rcritten@redhat.com>
Reviewed-By: Florence Blanc-Renaud <flo@redhat.com>
Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>
Reviewed-By: Timo Aaltonen <tjaalton@debian.org>
Reviewed-By: Antonio Torres Moríñigo <atorresm@protonmail.com>
2021-11-25 16:49:00 +01:00

244 lines
8.7 KiB
Python

#
# Copyright (C) 2014 FreeIPA Contributors see COPYING for license
#
from __future__ import absolute_import
from datetime import datetime
import logging
import dns.name
import errno
import os
import shutil
import stat
import six
import ipalib.constants
from ipapython.dn import DN
from ipapython import ipautil
from ipaplatform.constants import constants as platformconstants
from ipaplatform.paths import paths
from ipaserver.dnssec.temp import TemporaryDirectory
from ipaserver.install import installutils
logger = logging.getLogger(__name__)
time_bindfmt = '%Y%m%d%H%M%S'
# this daemon should run under ods:named user:group
# user has to be ods because ODSMgr.py sends signal to ods-enforcerd
FILE_PERM = (stat.S_IRUSR | stat.S_IRGRP | stat.S_IWGRP | stat.S_IWUSR)
DIR_PERM = (stat.S_IRWXU | stat.S_IRWXG)
class BINDMgr:
"""BIND key manager. It does LDAP->BIND key files synchronization.
One LDAP object with idnsSecKey object class will produce
single pair of BIND key files.
"""
def __init__(self, api):
self.api = api
self.ldap_keys = {}
self.modified_zones = set()
def notify_zone(self, zone):
cmd = ['rndc', 'sign', zone.to_text()]
result = ipautil.run(cmd, capture_output=True)
logger.info('%s', result.output_log)
def dn2zone_name(self, dn):
"""cn=KSK-20140813162153Z-cede9e182fc4af76c4bddbc19123a565,cn=keys,idnsname=test,cn=dns,dc=ipa,dc=example"""
# verify that metadata object is under DNS sub-tree
dn = DN(dn)
container = DN(self.api.env.container_dns, self.api.env.basedn)
idx = dn.rfind(container)
assert idx != -1, 'Metadata object %s is not inside %s' % (dn, container)
assert len(dn[idx - 1]) == 1, 'Multi-valued RDN as zone name is not supported'
return dns.name.from_text(dn[idx - 1]['idnsname'])
def time_ldap2bindfmt(self, str_val):
if isinstance(str_val, bytes):
str_val = str_val.decode('utf-8')
dt = datetime.strptime(
str_val,
ipalib.constants.LDAP_GENERALIZED_TIME_FORMAT
)
return dt.strftime(time_bindfmt).encode('utf-8')
def dates2params(self, ldap_attrs):
"""Convert LDAP timestamps to list of parameters suitable
for dnssec-keyfromlabel utility"""
attr2param = {'idnsseckeypublish': '-P',
'idnsseckeyactivate': '-A',
'idnsseckeyinactive': '-I',
'idnsseckeydelete': '-D'}
params = []
for attr, param in attr2param.items():
params.append(param)
if attr in ldap_attrs:
assert len(ldap_attrs[attr]) == 1, 'Timestamp %s is expected to be single-valued' % attr
params.append(self.time_ldap2bindfmt(ldap_attrs[attr][0]))
else:
params.append('none')
return params
def ldap_event(self, op, uuid, attrs):
"""Record single LDAP event - key addition, deletion or modification.
Change is only recorded to memory.
self.sync() has to be called to synchronize change to BIND."""
assert op in ('add', 'del', 'mod')
zone = self.dn2zone_name(attrs['dn'])
self.modified_zones.add(zone)
zone_keys = self.ldap_keys.setdefault(zone, {})
if op == 'add':
logger.info('Key metadata %s added to zone %s',
attrs['dn'], zone)
zone_keys[uuid] = attrs
elif op == 'del':
logger.info('Key metadata %s deleted from zone %s',
attrs['dn'], zone)
zone_keys.pop(uuid)
elif op == 'mod':
logger.info('Key metadata %s updated in zone %s',
attrs['dn'], zone)
zone_keys[uuid] = attrs
def install_key(self, zone, uuid, attrs, workdir):
"""Run dnssec-keyfromlabel on given LDAP object.
:returns: base file name of output files, e.g. Kaaa.test.+008+19719
"""
logger.info('attrs: %s', attrs)
assert attrs.get('idnsseckeyzone', [b'FALSE'])[0] == b'TRUE', \
b'object %s is not a DNS zone key' % attrs['dn']
uri = b"%s;pin-source=%s" % (
attrs['idnsSecKeyRef'][0],
paths.DNSSEC_SOFTHSM_PIN.encode('utf-8')
)
cmd = [
paths.DNSSEC_KEYFROMLABEL,
'-E', 'pkcs11',
'-K', workdir,
'-a', attrs['idnsSecAlgorithm'][0],
'-l', uri
]
cmd.extend(self.dates2params(attrs))
if attrs.get('idnsSecKeySep', [b'FALSE'])[0].upper() == b'TRUE':
cmd.extend(['-f', 'KSK'])
if attrs.get('idnsSecKeyRevoke', [b'FALSE'])[0].upper() == b'TRUE':
cmd.extend(['-R', datetime.now().strftime(time_bindfmt)])
if platformconstants.NAMED_OPENSSL_ENGINE is not None:
cmd.extend(['-E', platformconstants.NAMED_OPENSSL_ENGINE])
cmd.append(zone.to_text())
installutils.check_entropy()
# keys has to be readable by ODS & named
result = ipautil.run(cmd, capture_output=True)
basename = result.output.strip()
private_fn = "%s/%s.private" % (workdir, basename)
os.chmod(private_fn, FILE_PERM)
# this is useful mainly for debugging
with open("%s/%s.uuid" % (workdir, basename), 'w') as uuid_file:
uuid_file.write(uuid)
with open("%s/%s.dn" % (workdir, basename), 'w') as dn_file:
dn_file.write(attrs['dn'])
def get_zone_dir_name(self, zone):
"""Escape zone name to form suitable for file-system.
This method has to be equivalent to zr_get_zone_path()
in bind-dyndb-ldap/zone_register.c."""
if zone == dns.name.root:
return "@"
# strip final (empty) label
zone = zone.relativize(dns.name.root)
escaped = []
for label in zone:
for char in label:
if six.PY3:
char = chr(char)
if char.isalnum() or char in "-_":
escaped.append(char.lower())
else:
escaped.append("%%%02X" % ord(char))
escaped.append('.')
# strip trailing period
return ''.join(escaped[:-1])
def sync_zone(self, zone):
logger.info('Synchronizing zone %s', zone)
zone_path = os.path.join(paths.BIND_LDAP_DNS_ZONE_WORKDIR,
self.get_zone_dir_name(zone))
try:
os.mkdir(zone_path, 0o770)
except FileExistsError:
pass
# fix HSM permissions
# TODO: move out
for prefix, dirs, files in os.walk(paths.DNSSEC_TOKENS_DIR, topdown=True):
for name in dirs:
fpath = os.path.join(prefix, name)
logger.debug('Fixing directory permissions: %s', fpath)
os.chmod(fpath, DIR_PERM | stat.S_ISGID)
for name in files:
fpath = os.path.join(prefix, name)
logger.debug('Fixing file permissions: %s', fpath)
os.chmod(fpath, FILE_PERM)
# TODO: move out
with TemporaryDirectory(zone_path) as tempdir:
for uuid, attrs in self.ldap_keys[zone].items():
self.install_key(zone, uuid, attrs, tempdir)
# keys were generated in a temporary directory, swap directories
target_dir = "%s/keys" % zone_path
try:
shutil.rmtree(target_dir)
except OSError as e:
if e.errno != errno.ENOENT:
raise e
shutil.move(tempdir, target_dir)
os.chmod(target_dir, DIR_PERM)
self.notify_zone(zone)
def sync(self, dnssec_zones):
"""Synchronize list of zones in LDAP with BIND.
dnssec_zones lists zones which should be processed. All other zones
will be ignored even though they were modified using ldap_event().
This filter is useful in cases where LDAP contains DNS zones which
have old metadata objects and DNSSEC disabled. Such zones must be
ignored to prevent errors while calling dnssec-keyfromlabel or rndc.
"""
logger.debug('Key metadata in LDAP: %s', self.ldap_keys)
logger.debug('Zones modified but skipped during bindmgr.sync: %s',
self.modified_zones - dnssec_zones)
for zone in self.modified_zones.intersection(dnssec_zones):
self.sync_zone(zone)
self.modified_zones = set()
def diff_zl(self, s1, s2):
"""Compute zones present in s1 but not present in s2.
Returns: List of (uuid, name) tuples with zones present only in s1."""
s1_extra = s1.uuids - s2.uuids
removed = [(uuid, name) for (uuid, name) in s1.mapping.items()
if uuid in s1_extra]
return removed