path: root/ipaserver/install/server/replicainstall.py

#
# Copyright (C) 2015  FreeIPA Contributors see COPYING for license
#

from __future__ import print_function

import contextlib
import dns.exception as dnsexception
import dns.name as dnsname
import dns.resolver as dnsresolver
import dns.reversename as dnsreversename
import os
import shutil
import socket
import tempfile
import traceback

from pkg_resources import parse_version
import six

from ipaclient.install.ipachangeconf import IPAChangeConf
import ipaclient.install.ntpconf
from ipalib.install import certstore, sysrestore
from ipalib.install.kinit import kinit_keytab
from ipapython import ipaldap, ipautil
from ipapython.dn import DN
from ipapython.ipa_log_manager import root_logger
from ipapython.admintool import ScriptError
from ipaplatform import services
from ipaplatform.constants import constants as pconstants
from ipaplatform.tasks import tasks
from ipaplatform.paths import paths
from ipalib import api, constants, create_api, errors, rpc, x509
from ipalib.config import Env
from ipalib.util import (
    network_ip_address_warning,
    broadcast_ip_address_warning,
)
from ipaclient.install.client import configure_krb5_conf, purge_host_keytab
from ipaserver.install import (
    adtrust, bindinstance, ca, certs, dns, dsinstance, httpinstance,
    installutils, kra, krbinstance,
    ntpinstance, otpdinstance, custodiainstance, service)
from ipaserver.install.installutils import (
    create_replica_config, ReplicaConfig, load_pkcs12, is_ipa_configured,
    create_ipaapi_user)
from ipaserver.install.replication import (
    ReplicationManager, replica_conn_check)
import SSSDConfig
from subprocess import CalledProcessError

if six.PY3:
    unicode = str

NoneType = type(None)


def get_dirman_password():
    return installutils.read_password("Directory Manager (existing master)",
                                      confirm=False, validate=False)


def make_pkcs12_info(directory, cert_name, password_name):
    """Make pkcs12_info

    :param directory: Base directory (config.dir)
    :param cert_name: Cert filename (e.g. "dscert.p12")
    :param password_name: Cert filename (e.g. "dirsrv_pin.txt")
    :return: a (full cert path, password) tuple, or None if cert is not found
    """
    cert_path = os.path.join(directory, cert_name)
    if ipautil.file_exists(cert_path):
        password_file = os.path.join(directory, password_name)
        password = open(password_file).read().strip()
        return cert_path, password
    else:
        return None


def install_http_certs(host_name, realm_name, subject_base):
    principal = 'HTTP/%s@%s' % (host_name, realm_name)
    subject = subject_base or DN(('O', realm_name))
    db = certs.CertDB(realm_name, nssdir=paths.HTTPD_ALIAS_DIR,
                      subject_base=subject, user="root",
                      group=pconstants.HTTPD_GROUP, truncate=True)
    db.request_service_cert('Server-Cert', principal, host_name)
    # Obtain certificate for the HTTP service
    http = httpinstance.HTTPInstance()
    http.create_password_conf()


def install_replica_ds(config, options, ca_is_configured, remote_api,
                       ca_file, promote=False, pkcs12_info=None):
    dsinstance.check_ports()

    # if we have a pkcs12 file, create the cert db from
    # that. Otherwise the ds setup will create the CA
    # cert
    if pkcs12_info is None:
        pkcs12_info = make_pkcs12_info(config.dir, "dscert.p12",
                                       "dirsrv_pin.txt")

    if ca_is_configured:
        ca_subject = ca.lookup_ca_subject(remote_api, config.subject_base)
    else:
        ca_subject = installutils.default_ca_subject_dn(config.subject_base)

    ds = dsinstance.DsInstance(
        config_ldif=options.dirsrv_config_file)
    ds.create_replica(
        realm_name=config.realm_name,
        master_fqdn=config.master_host_name,
        fqdn=config.host_name,
        domain_name=config.domain_name,
        dm_password=config.dirman_password,
        subject_base=config.subject_base,
        ca_subject=ca_subject,
        pkcs12_info=pkcs12_info,
        ca_is_configured=ca_is_configured,
        ca_file=ca_file,
        promote=promote,  # we need promote because of replication setup
        api=remote_api,
    )

    return ds


def install_krb(config, setup_pkinit=False, promote=False):
    krb = krbinstance.KrbInstance()

    # pkinit files
    pkcs12_info = make_pkcs12_info(config.dir, "pkinitcert.p12",
                                   "pkinit_pin.txt")

    krb.create_replica(config.realm_name,
                       config.master_host_name, config.host_name,
                       config.domain_name, config.dirman_password,
                       setup_pkinit, pkcs12_info,
                       subject_base=config.subject_base,
                       promote=promote)

    return krb


def install_ca_cert(ldap, base_dn, realm, cafile, destfile=paths.IPA_CA_CRT):
    try:
        try:
            certs = certstore.get_ca_certs(ldap, base_dn, realm, False)
        except errors.NotFound:
            try:
                shutil.copy(cafile, destfile)
            except shutil.Error:
                # cafile == IPA_CA_CRT
                pass
        else:
            certs = [c[0] for c in certs if c[2] is not False]
            x509.write_certificate_list(certs, destfile)
    except Exception as e:
        raise ScriptError("error copying files: " + str(e))
    return destfile


def install_http(config, auto_redirect, ca_is_configured, ca_file,
                 promote=False,
                 pkcs12_info=None):
    # if we have a pkcs12 file, create the cert db from
    # that. Otherwise the ds setup will create the CA
    # cert
    if pkcs12_info is None:
        pkcs12_info = make_pkcs12_info(config.dir, "httpcert.p12",
                                       "http_pin.txt")


    http = httpinstance.HTTPInstance()
    http.create_instance(
        config.realm_name, config.host_name, config.domain_name,
        pkcs12_info, auto_redirect=auto_redirect, ca_file=ca_file,
        ca_is_configured=ca_is_configured, promote=promote)

    return http


def install_dns_records(config, options, remote_api):

    if not bindinstance.dns_container_exists(
            ipautil.realm_to_suffix(config.realm_name)):
        return

    try:
        bind = bindinstance.BindInstance(api=remote_api)
        for ip in config.ips:
            reverse_zone = bindinstance.find_reverse_zone(ip, remote_api)

            bind.add_master_dns_records(config.host_name,
                                        str(ip),
                                        config.realm_name,
                                        config.domain_name,
                                        reverse_zone)
    except errors.NotFound as e:
        root_logger.debug('Replica DNS records could not be added '
                          'on master: %s', str(e))

    # we should not fail here no matter what
    except Exception as e:
        root_logger.info('Replica DNS records could not be added '
                         'on master: %s', str(e))


def create_ipa_conf(fstore, config, ca_enabled):
    # Save client file on Domain Level 1
    target_fname = paths.IPA_DEFAULT_CONF
    fstore.backup_file(target_fname)

    ipaconf = IPAChangeConf("IPA Replica Install")
    ipaconf.setOptionAssignment(" = ")
    ipaconf.setSectionNameDelimiters(("[", "]"))

    xmlrpc_uri = 'https://{0}/ipa/xml'.format(
                    ipautil.format_netloc(config.host_name))
    ldapi_uri = 'ldapi://%2fvar%2frun%2fslapd-{0}.socket\n'.format(
                    installutils.realm_to_serverid(config.realm_name))

    # [global] section
    gopts = [
        ipaconf.setOption('basedn', str(config.basedn)),
        ipaconf.setOption('host', config.host_name),
        ipaconf.setOption('realm', config.realm_name),
        ipaconf.setOption('domain', config.domain_name),
        ipaconf.setOption('xmlrpc_uri', xmlrpc_uri),
        ipaconf.setOption('ldap_uri', ldapi_uri),
        ipaconf.setOption('mode', 'production')
    ]

    if ca_enabled:
        gopts.extend([
            ipaconf.setOption('enable_ra', 'True'),
            ipaconf.setOption('ra_plugin', 'dogtag'),
            ipaconf.setOption('dogtag_version', '10')
        ])

        if not config.setup_ca:
            gopts.append(ipaconf.setOption('ca_host', config.ca_host_name))
    else:
        gopts.extend([
            ipaconf.setOption('enable_ra', 'False'),
            ipaconf.setOption('ra_plugin', 'None')
        ])

    opts = [
        ipaconf.setSection('global', gopts),
        {'name': 'empty', 'type': 'empty'}
    ]
    ipaconf.newConf(target_fname, opts)
    # the new file must be readable for httpd
    # Also, umask applies when creating a new file but we want 0o644 here
    os.chmod(target_fname, 0o644)


def check_dirsrv():
    (ds_unsecure, ds_secure) = dsinstance.check_ports()
    if not ds_unsecure or not ds_secure:
        msg = ("IPA requires ports 389 and 636 for the Directory Server.\n"
               "These are currently in use:\n")
        if not ds_unsecure:
            msg += "\t389\n"
        if not ds_secure:
            msg += "\t636\n"
        raise ScriptError(msg)


def check_dns_resolution(host_name, dns_servers):
    """Check forward and reverse resolution of host_name using dns_servers
    """
    # Point the resolver at specified DNS server
    server_ips = []
    for dns_server in dns_servers:
        try:
            server_ips = list(
                a[4][0] for a in socket.getaddrinfo(dns_server, None))
        except socket.error:
            pass
        else:
            break
    if not server_ips:
        root_logger.error(
            'Could not resolve any DNS server hostname: %s', dns_servers)
        return False
    resolver = dnsresolver.Resolver()
    resolver.nameservers = server_ips

    root_logger.debug('Search DNS server %s (%s) for %s',
                      dns_server, server_ips, host_name)

    # Get IP addresses of host_name
    addresses = set()
    for rtype in 'A', 'AAAA':
        try:
            result = resolver.query(host_name, rtype)
        except dnsexception.DNSException:
            rrset = []
        else:
            rrset = result.rrset
        if rrset:
            addresses.update(r.address for r in result.rrset)

    if not addresses:
        root_logger.error(
            'Could not resolve hostname %s using DNS. '
            'Clients may not function properly. '
            'Please check your DNS setup. '
            '(Note that this check queries IPA DNS directly and '
            'ignores /etc/hosts.)',
            host_name)
        return False

    no_errors = True

    # Check each of the IP addresses
    checked = set()
    for address in addresses:
        if address in checked:
            continue
        checked.add(address)
        try:
            root_logger.debug('Check reverse address %s (%s)',
                              address, host_name)
            revname = dnsreversename.from_address(address)
            rrset = resolver.query(revname, 'PTR').rrset
        except Exception as e:
            root_logger.debug('Check failed: %s %s', type(e).__name__, e)
            root_logger.error(
                'Reverse DNS resolution of address %s (%s) failed. '
                'Clients may not function properly. '
                'Please check your DNS setup. '
                '(Note that this check queries IPA DNS directly and '
                'ignores /etc/hosts.)',
                address, host_name)
            no_errors = False
        else:
            host_name_obj = dnsname.from_text(host_name)
            if rrset:
                names = [r.target.to_text() for r in rrset]
            else:
                names = []
            root_logger.debug(
                'Address %s resolves to: %s. ', address, ', '.join(names))
            if not rrset or not any(
                    r.target == host_name_obj for r in rrset):
                root_logger.error(
                    'The IP address %s of host %s resolves to: %s. '
                    'Clients may not function properly. '
                    'Please check your DNS setup. '
                    '(Note that this check queries IPA DNS directly and '
                    'ignores /etc/hosts.)',
                    address, host_name, ', '.join(names))
                no_errors = False

    return no_errors


def configure_certmonger():
    messagebus = services.knownservices.messagebus
    try:
        messagebus.start()
    except Exception as e:
        raise ScriptError("Messagebus service unavailable: %s" % str(e),
                          rval=3)

    # Ensure that certmonger has been started at least once to generate the
    # cas files in /var/lib/certmonger/cas.
    cmonger = services.knownservices.certmonger
    try:
        cmonger.restart()
    except Exception as e:
        raise ScriptError("Certmonger service unavailable: %s" % str(e),
                          rval=3)

    try:
        cmonger.enable()
    except Exception as e:
        raise ScriptError("Failed to enable Certmonger: %s" % str(e),
                          rval=3)


def remove_replica_info_dir(installer):
    # always try to remove decrypted replica file
    try:
        if installer._top_dir is not None:
            shutil.rmtree(installer._top_dir)
    except OSError:
        pass


def common_cleanup(func):
    def decorated(installer):
        try:
            try:
                func(installer)
            except BaseException:
                remove_replica_info_dir(installer)
                raise
        except KeyboardInterrupt:
            raise ScriptError()
        except Exception:
            print(
                "Your system may be partly configured.\n"
                "Run /usr/sbin/ipa-server-install --uninstall to clean up.\n")
            raise

    return decorated


def preserve_enrollment_state(func):
    """
    Makes sure the machine is unenrollled if the decorated function
    failed.
    """
    def decorated(installer):
        try:
            func(installer)
        except BaseException:
            if installer._enrollment_performed:
                uninstall_client()
            raise

    return decorated


def uninstall_client():
    """
    Attempts to unenroll the IPA client using the ipa-client-install utility.

    An unsuccessful attempt to uninstall is ignored (no exception raised).
    """

    print("Removing client side components")
    ipautil.run([paths.IPA_CLIENT_INSTALL, "--unattended", "--uninstall"],
                raiseonerr=False, redirect_output=True)
    print()


def promote_sssd(host_name):
    sssdconfig = SSSDConfig.SSSDConfig()
    sssdconfig.import_config()
    domains = sssdconfig.list_active_domains()

    ipa_domain = None

    for name in domains:
        domain = sssdconfig.get_domain(name)
        try:
            hostname = domain.get_option('ipa_hostname')
            if hostname == host_name:
                ipa_domain = domain
        except SSSDConfig.NoOptionError:
            continue

    if ipa_domain is None:
        raise RuntimeError("Couldn't find IPA domain in sssd.conf")
    else:
        domain.set_option('ipa_server', host_name)
        domain.set_option('ipa_server_mode', True)
        sssdconfig.save_domain(domain)
        sssdconfig.write()

        sssd = services.service('sssd', api)
        try:
            sssd.restart()
        except CalledProcessError:
            root_logger.warning("SSSD service restart was unsuccessful.")


def promote_openldap_conf(hostname, master):
    """
    Reset the URI directive in openldap-client configuration file to point to
    newly promoted replica. If this directive was set by third party, then
    replace the added comment with the one pointing to replica

    :param hostname: replica FQDN
    :param master: FQDN of remote master
    """

    ldap_conf = paths.OPENLDAP_LDAP_CONF

    ldap_change_conf = IPAChangeConf("IPA replica installer")
    ldap_change_conf.setOptionAssignment((" ", "\t"))

    new_opts = []

    with open(ldap_conf, 'r') as f:
        old_opts = ldap_change_conf.parse(f)

        for opt in old_opts:
            if opt['type'] == 'comment' and master in opt['value']:
                continue
            elif (opt['type'] == 'option' and opt['name'] == 'URI' and
                    master in opt['value']):
                continue
            new_opts.append(opt)

    change_opts = [
        {'action': 'addifnotset',
         'name': 'URI',
         'type': 'option',
         'value': 'ldaps://' + hostname}
    ]

    try:
        ldap_change_conf.newConf(ldap_conf, new_opts)
        ldap_change_conf.changeConf(ldap_conf, change_opts)
    except Exception as e:
        root_logger.info("Failed to update {}: {}".format(ldap_conf, e))


@contextlib.contextmanager
def rpc_client(api):
    """
    Context manager for JSON RPC client.

    :param api: api to initiate the RPC client
    """
    client = rpc.jsonclient(api)
    client.finalize()
    client.connect()

    try:
        yield client
    finally:
        client.disconnect()


def check_remote_fips_mode(client, local_fips_mode):
    """
    Verify remote server's fips-mode is the same as this server's fips-mode

    :param client: RPC client
    :param local_fips_mode: boolean indicating whether FIPS mode is turned on
    :raises: ScriptError: if the checks fails
    """
    env = client.forward(u'env', u'fips_mode')['result']
    remote_fips_mode = env.get('fips_mode', False)
    if local_fips_mode != remote_fips_mode:
        if local_fips_mode:
            raise ScriptError(
                "Cannot join FIPS-enabled replica into existing topology: "
                "FIPS is not enabled on the master server.")
        else:
            raise ScriptError(
                "Cannot join replica into existing FIPS-enabled topology: "
                "FIPS has to be enabled locally first.")


def check_remote_version(client, local_version):
    """
    Verify remote server's version is not higher than this server's version

    :param client: RPC client
    :param local_version: API version of local server
    :raises: ScriptError: if the checks fails
    """
    env = client.forward(u'env', u'version')['result']
    remote_version = parse_version(env['version'])
    if remote_version > local_version:
        raise ScriptError(
            "Cannot install replica of a server of higher version ({}) than"
            "the local version ({})".format(remote_version, local_version))


def common_check(no_ntp):
    tasks.check_ipv6_stack_enabled()
    tasks.check_selinux_status()

    if is_ipa_configured():
        raise ScriptError(
            "IPA server is already configured on this system.\n"
            "If you want to reinstall the IPA server, please uninstall "
            "it first using 'ipa-server-install --uninstall'.")

    # Check to see if httpd is already configured to listen on 443
    if httpinstance.httpd_443_configured():
        raise ScriptError("Aborting installation")

    check_dirsrv()

    if not no_ntp:
        try:
            ipaclient.install.ntpconf.check_timedate_services()
        except ipaclient.install.ntpconf.NTPConflictingService as e:
            print("WARNING: conflicting time&date synchronization service "
                  "'{svc}' will\nbe disabled in favor of ntpd\n"
                  .format(svc=e.conflicting_service))
        except ipaclient.install.ntpconf.NTPConfigurationError:
            pass


def current_domain_level(api):
    """Return the current domain level.

    """
    # Detect the current domain level
    try:
        return api.Command['domainlevel_get']()['result']
    except errors.NotFound:
        # If we're joining an older master, domain entry is not
        # available
        return constants.DOMAIN_LEVEL_0


def check_domain_level_is_supported(current):
    """Check that the given domain level is supported by this server version.

    :raises: ScriptError if DL is out of supported range for this IPA version.

    """
    under_lower_bound = current < constants.MIN_DOMAIN_LEVEL
    above_upper_bound = current > constants.MAX_DOMAIN_LEVEL

    if under_lower_bound or above_upper_bound:
        message = ("This version of FreeIPA does not support "
                   "the Domain Level which is currently set for "
                   "this domain. The Domain Level needs to be "
                   "raised before installing a replica with "
                   "this version is allowed to be installed "
                   "within this domain.")
        root_logger.error(message)
        raise ScriptError(message, rval=3)


def enroll_dl0_replica(installer, fstore, remote_api, debug=False):
    """
    Do partial host enrollment in DL0:
        * add host entry to remote master
        * request host keytab from remote master
        * configure client-like /etc/krb5.conf to enable GSSAPI auth further
          down the replica installation
    """
    root_logger.info("Enrolling host to IPA domain")
    config = installer._config
    hostname = config.host_name

    try:
        installer._enrollment_performed = True
        host_result = remote_api.Command.host_add(
            unicode(config.host_name))['result']

        host_princ = unicode(host_result['krbcanonicalname'][0])
        purge_host_keytab(config.realm_name)

        getkeytab_args = [
            paths.IPA_GETKEYTAB,
            '-s', config.master_host_name,
            '-p', host_princ,
            '-D', unicode(ipaldap.DIRMAN_DN),
            '-w', config.dirman_password,
            '-k', paths.KRB5_KEYTAB,
            '--cacert', os.path.join(config.dir, 'ca.crt')
        ]
        ipautil.run(getkeytab_args, nolog=(config.dirman_password,))

        _hostname, _sep, host_domain = hostname.partition('.')

        fstore.backup_file(paths.KRB5_CONF)
        configure_krb5_conf(
            config.realm_name,
            config.domain_name,
            [config.master_host_name],
            [config.master_host_name],
            False,
            paths.KRB5_CONF,
            host_domain,
            hostname,
            configure_sssd=False
        )

    except CalledProcessError as e:
        raise RuntimeError("Failed to fetch host keytab: {}".format(e))


@common_cleanup
@preserve_enrollment_state
def install_check(installer):
    options = installer
    filename = installer.replica_file
    installer._enrollment_performed = False

    if tasks.is_fips_enabled():
        raise RuntimeError(
            "Installing IPA server in FIPS mode on domain level 0 is not "
            "supported")

    # check selinux status, http and DS ports, NTP conflicting services
    common_check(options.no_ntp)

    client_fstore = sysrestore.FileStore(paths.IPA_CLIENT_SYSRESTORE)
    if client_fstore.has_files():
        raise ScriptError(
            "IPA client is already configured on this system.\n"
            "Please uninstall it first before configuring the replica, "
            "using 'ipa-client-install --uninstall'.")

    sstore = sysrestore.StateFile(paths.SYSRESTORE)

    fstore = sysrestore.FileStore(paths.SYSRESTORE)

    # get the directory manager password
    dirman_password = options.password
    if not dirman_password:
        try:
            dirman_password = get_dirman_password()
        except KeyboardInterrupt:
            raise ScriptError(rval=0)
        if dirman_password is None:
            raise ScriptError("Directory Manager password required")

    config = create_replica_config(dirman_password, filename, options)
    config.ca_host_name = config.master_host_name
    config.kra_host_name = config.ca_host_name

    config.setup_ca = options.setup_ca
    config.setup_kra = options.setup_kra
    config.basedn = ipautil.realm_to_suffix(config.realm_name)
    installer._top_dir = config.top_dir
    installer._config = config

    ca_enabled = ipautil.file_exists(os.path.join(config.dir, "cacert.p12"))
    # Create the management framework config file
    # Note: We must do this before bootstraping and finalizing ipalib.api
    create_ipa_conf(fstore, config, ca_enabled)

    api.bootstrap(in_server=True, context='installer', confdir=paths.ETC_IPA)
    api.finalize()

    installutils.verify_fqdn(config.master_host_name, options.no_host_dns)

    cafile = os.path.join(config.dir, "ca.crt")
    if not ipautil.file_exists(cafile):
        raise RuntimeError("CA cert file is not available. Please run "
                           "ipa-replica-prepare to create a new replica file.")

    # look up CA subject name (needed for DS certmap.conf)
    options.ca_subject = unicode(
        DN(x509.load_certificate_from_file(cafile).subject))

    for pkcs12_name, pin_name in (('dscert.p12', 'dirsrv_pin.txt'),
                                  ('httpcert.p12', 'http_pin.txt')):
        pkcs12_info = make_pkcs12_info(config.dir, pkcs12_name, pin_name)
        tmp_db_dir = tempfile.mkdtemp('ipa')
        try:
            tmp_db = certs.CertDB(config.realm_name,
                                  nssdir=tmp_db_dir,
                                  subject_base=config.subject_base)
            if ca_enabled:
                trust_flags = 'CT,C,C'
            else:
                trust_flags = None
            tmp_db.create_from_pkcs12(pkcs12_info[0], pkcs12_info[1],
                                      ca_file=cafile,
                                      trust_flags=trust_flags)
            if not tmp_db.find_server_certs():
                raise RuntimeError(
                    "Could not find a suitable server cert in import in %s" %
                    pkcs12_info[0])
        except Exception as e:
            root_logger.error('%s', e)
            raise RuntimeError(
                "Server cert is not valid. Please run ipa-replica-prepare to "
                "create a new replica file.")
        finally:
            shutil.rmtree(tmp_db_dir)

    ldapuri = 'ldaps://%s' % ipautil.format_netloc(config.master_host_name)
    remote_api = create_api(mode=None)
    remote_api.bootstrap(in_server=True,
                         context='installer',
                         confdir=paths.ETC_IPA,
                         ldap_uri=ldapuri)
    remote_api.finalize()
    installer._remote_api = remote_api

    conn = remote_api.Backend.ldap2
    replman = None
    try:
        # Try out the password
        conn.connect(bind_dn=ipaldap.DIRMAN_DN, bind_pw=config.dirman_password,
                     cacert=cafile)
        replman = ReplicationManager(config.realm_name,
                                     config.master_host_name,
                                     config.dirman_password)

        # Check that we don't already have a replication agreement
        if replman.get_replication_agreement(config.host_name):
            root_logger.info('Error: A replication agreement for this '
                             'host already exists.')
            msg = ("A replication agreement for this host already exists. "
                   "It needs to be removed.\n"
                   "Run this on the master that generated the info file:\n"
                   "    %% ipa-replica-manage del %s --force" %
                   config.host_name)
            raise ScriptError(msg, rval=3)

        domain_level = current_domain_level(remote_api)
        check_domain_level_is_supported(domain_level)
        if domain_level != constants.DOMAIN_LEVEL_0:
            raise RuntimeError(
                "You must provide a file generated by ipa-replica-prepare to "
                "create a replica when the domain is at level 0."
            )

        # Check pre-existing host entry
        try:
            conn.find_entries(
                u'fqdn=%s' % config.host_name, ['fqdn'],
                DN(api.env.container_host, api.env.basedn))
        except errors.NotFound:
            pass
        else:
            root_logger.info('Error: Host %s already exists on the master '
                             'server.' % config.host_name)
            msg = ("The host %s already exists on the master server.\n"
                   "You should remove it before proceeding:\n"
                   "    %% ipa host-del %s" %
                   (config.host_name, config.host_name))
            raise ScriptError(msg, rval=3)

        dns_masters = remote_api.Object['dnsrecord'].get_dns_masters()
        if dns_masters:
            if not options.no_host_dns:
                master = config.master_host_name
                root_logger.debug('Check forward/reverse DNS resolution')
                resolution_ok = (
                    check_dns_resolution(master, dns_masters) and
                    check_dns_resolution(config.host_name, dns_masters))
                if not resolution_ok and installer.interactive:
                    if not ipautil.user_input("Continue?", False):
                        raise ScriptError(rval=0)
        else:
            root_logger.debug('No IPA DNS servers, '
                              'skipping forward/reverse resolution check')

        kra_enabled = remote_api.Command.kra_is_enabled()['result']

        if ca_enabled:
            options.realm_name = config.realm_name
            options.host_name = config.host_name
            ca.install_check(False, config, options)

        if kra_enabled:
            try:
                kra.install_check(remote_api, config, options)
            except RuntimeError as e:
                raise ScriptError(e)

        if options.setup_dns:
            dns.install_check(False, remote_api, True, options,
                              config.host_name)
            config.ips = dns.ip_addresses
        else:
            config.ips = installutils.get_server_ip_address(
                config.host_name, not installer.interactive, False,
                options.ip_addresses)

            # check addresses here, dns module is doing own check
            network_ip_address_warning(config.ips)
            broadcast_ip_address_warning(config.ips)

        if options.setup_adtrust:
            adtrust.install_check(False, options, remote_api)

        enroll_dl0_replica(installer, fstore, remote_api)
        ccache = os.environ['KRB5CCNAME']
        kinit_keytab('host/{env.host}@{env.realm}'.format(env=api.env),
                     paths.KRB5_KEYTAB,
                     ccache)

    except errors.ACIError:
        raise ScriptError("\nThe password provided is incorrect for LDAP server "
                          "%s" % config.master_host_name)
    except errors.LDAPError:
        raise ScriptError("\nUnable to connect to LDAP server %s" %
                          config.master_host_name)
    finally:
        if replman and replman.conn:
            replman.conn.unbind()
        if conn.isconnected():
            conn.disconnect()

    # installer needs to update hosts file when DNS subsystem will be
    # installed or custom addresses are used
    if options.setup_dns or options.ip_addresses:
        installer._update_hosts_file = True

    # check connection
    if not options.skip_conncheck:
        try:
            del os.environ['KRB5CCNAME']
            replica_conn_check(
                config.master_host_name, config.host_name, config.realm_name,
                options.setup_ca, config.ca_ds_port, options.admin_password,
                ca_cert_file=cafile)
        finally:
            os.environ['KRB5CCNAME'] = ccache

    installer._ca_enabled = ca_enabled
    installer._kra_enabled = kra_enabled
    installer._ca_file = cafile
    installer._fstore = fstore
    installer._sstore = sstore


def ensure_enrolled(installer):
    # Call client install script
    service.print_msg("Configuring client side components")
    try:
        installer._enrollment_performed = True

        args = [paths.IPA_CLIENT_INSTALL, "--unattended", "--no-ntp"]
        stdin = None
        nolog = []

        if installer.domain_name:
            args.extend(["--domain", installer.domain_name])
        if installer.server:
            args.extend(["--server", installer.server])
        if installer.realm_name:
            args.extend(["--realm", installer.realm_name])
        if installer.host_name:
            args.extend(["--hostname", installer.host_name])

        if installer.password:
            args.extend(["--password", installer.password])
            nolog.append(installer.password)
        else:
            if installer.admin_password:
                # Always set principal if password was set explicitly,
                # the password itself gets passed directly via stdin
                args.extend(["--principal", installer.principal or "admin"])
                stdin = installer.admin_password
            if installer.keytab:
                args.extend(["--keytab", installer.keytab])

        if installer.no_dns_sshfp:
            args.append("--no-dns-sshfp")
        if installer.ssh_trust_dns:
            args.append("--ssh-trust-dns")
        if installer.no_ssh:
            args.append("--no-ssh")
        if installer.no_sshd:
            args.append("--no-sshd")
        if installer.mkhomedir:
            args.append("--mkhomedir")

        ipautil.run(args, stdin=stdin, nolog=nolog, redirect_output=True)
        print()
    except Exception:
        raise ScriptError("Configuration of client side components failed!")


def promotion_check_ipa_domain(master_ldap_conn, basedn):
    entry = master_ldap_conn.get_entry(basedn, ['associatedDomain'])
    if not 'associatedDomain' in entry:
        raise RuntimeError('IPA domain not found in LDAP.')

    if len(entry['associatedDomain']) > 1:
        root_logger.critical(
            "Multiple IPA domains found. We are so sorry :-(, you are "
            "probably experiencing this bug "
            "https://fedorahosted.org/freeipa/ticket/5976. Please contact us "
            "for help.")
        raise RuntimeError(
            'Multiple IPA domains found in LDAP database ({domains}). '
            'Only one domain is allowed.'.format(
                domains=u', '.join(entry['associatedDomain'])
            ))

    if entry['associatedDomain'][0] != api.env.domain:
        raise RuntimeError(
            "Cannot promote this client to a replica. Local domain "
            "'{local}' does not match IPA domain '{ipadomain}'. ".format(
                local=api.env.domain,
                ipadomain=entry['associatedDomain'][0]
        ))


@common_cleanup
@preserve_enrollment_state
def promote_check(installer):
    options = installer
    installer._enrollment_performed = False
    installer._top_dir = tempfile.mkdtemp("ipa")

    # check selinux status, http and DS ports, NTP conflicting services
    common_check(options.no_ntp)

    client_fstore = sysrestore.FileStore(paths.IPA_CLIENT_SYSRESTORE)
    if not client_fstore.has_files():
        ensure_enrolled(installer)
    else:
        if (options.domain_name or options.server or options.realm_name or
                options.host_name or options.password or options.keytab):
            print("IPA client is already configured on this system, ignoring "
                  "the --domain, --server, --realm, --hostname, --password "
                  "and --keytab options.")

    sstore = sysrestore.StateFile(paths.SYSRESTORE)

    fstore = sysrestore.FileStore(paths.SYSRESTORE)

    env = Env()
    env._bootstrap(context='installer', confdir=paths.ETC_IPA, log=None)
    env._finalize_core(**dict(constants.DEFAULT_CONFIG))

    # pylint: disable=no-member
    xmlrpc_uri = 'https://{}/ipa/xml'.format(ipautil.format_netloc(env.host))
    api.bootstrap(in_server=True,
                  context='installer',
                  confdir=paths.ETC_IPA,
                  ldap_uri=installutils.realm_to_ldapi_uri(env.realm),
                  xmlrpc_uri=xmlrpc_uri)
    # pylint: enable=no-member
    api.finalize()

    config = ReplicaConfig()
    config.realm_name = api.env.realm
    config.host_name = api.env.host
    config.domain_name = api.env.domain
    config.master_host_name = api.env.server
    config.ca_host_name = api.env.ca_host
    config.kra_host_name = config.ca_host_name
    config.ca_ds_port = 389
    config.setup_ca = options.setup_ca
    config.setup_kra = options.setup_kra
    config.dir = installer._top_dir
    config.basedn = api.env.basedn

    http_pkcs12_file = None
    http_pkcs12_info = None
    dirsrv_pkcs12_file = None
    dirsrv_pkcs12_info = None
    pkinit_pkcs12_file = None
    pkinit_pkcs12_info = None

    if options.http_cert_files:
        if options.http_pin is None:
            options.http_pin = installutils.read_password(
                "Enter Apache Server private key unlock",
                confirm=False, validate=False)
            if options.http_pin is None:
                raise ScriptError(
                    "Apache Server private key unlock password required")
        http_pkcs12_file, http_pin, http_ca_cert = load_pkcs12(
            cert_files=options.http_cert_files,
            key_password=options.http_pin,
            key_nickname=options.http_cert_name,
            ca_cert_files=options.ca_cert_files,
            host_name=config.host_name)
        http_pkcs12_info = (http_pkcs12_file.name, http_pin)

    if options.dirsrv_cert_files:
        if options.dirsrv_pin is None:
            options.dirsrv_pin = installutils.read_password(
                "Enter Directory Server private key unlock",
                confirm=False, validate=False)
            if options.dirsrv_pin is None:
                raise ScriptError(
                    "Directory Server private key unlock password required")
        dirsrv_pkcs12_file, dirsrv_pin, dirsrv_ca_cert = load_pkcs12(
            cert_files=options.dirsrv_cert_files,
            key_password=options.dirsrv_pin,
            key_nickname=options.dirsrv_cert_name,
            ca_cert_files=options.ca_cert_files,
            host_name=config.host_name)
        dirsrv_pkcs12_info = (dirsrv_pkcs12_file.name, dirsrv_pin)

    if options.pkinit_cert_files:
        if options.pkinit_pin is None:
            options.pkinit_pin = installutils.read_password(
                "Enter Kerberos KDC private key unlock",
                confirm=False, validate=False)
            if options.pkinit_pin is None:
                raise ScriptError(
                    "Kerberos KDC private key unlock password required")
        pkinit_pkcs12_file, pkinit_pin, _pkinit_ca_cert = load_pkcs12(
            cert_files=options.pkinit_cert_files,
            key_password=options.pkinit_pin,
            key_nickname=options.pkinit_cert_name,
            ca_cert_files=options.ca_cert_files,
            host_name=config.host_name)
        pkinit_pkcs12_info = (pkinit_pkcs12_file.name, pkinit_pin)

    if (options.http_cert_files and options.dirsrv_cert_files and
            http_ca_cert != dirsrv_ca_cert):
        raise RuntimeError("Apache Server SSL certificate and Directory "
                           "Server SSL certificate are not signed by the same"
                           " CA certificate")

    installutils.verify_fqdn(config.host_name, options.no_host_dns)
    installutils.verify_fqdn(config.master_host_name, options.no_host_dns)

    ccache = os.environ['KRB5CCNAME']
    kinit_keytab('host/{env.host}@{env.realm}'.format(env=api.env),
                 paths.KRB5_KEYTAB,
                 ccache)

    cafile = paths.IPA_CA_CRT
    if not ipautil.file_exists(cafile):
        raise RuntimeError("CA cert file is not available! Please reinstall"
                           "the client and try again.")

    ldapuri = 'ldaps://%s' % ipautil.format_netloc(config.master_host_name)
    xmlrpc_uri = 'https://{}/ipa/xml'.format(
        ipautil.format_netloc(config.master_host_name))
    remote_api = create_api(mode=None)
    remote_api.bootstrap(in_server=True,
                         context='installer',
                         confdir=paths.ETC_IPA,
                         ldap_uri=ldapuri,
                         xmlrpc_uri=xmlrpc_uri)
    remote_api.finalize()
    installer._remote_api = remote_api

    with rpc_client(remote_api) as client:
        check_remote_version(client, api.env.version)
        check_remote_fips_mode(client, api.env.fips_mode)

    conn = remote_api.Backend.ldap2
    replman = None
    try:
        # Try out authentication
        conn.connect(ccache=ccache)
        replman = ReplicationManager(config.realm_name,
                                     config.master_host_name, None)

        promotion_check_ipa_domain(conn, remote_api.env.basedn)

        domain_level = current_domain_level(remote_api)
        check_domain_level_is_supported(domain_level)
        if domain_level < constants.DOMAIN_LEVEL_1:
            raise RuntimeError(
                "You used the wrong mechanism to install a replica in "
                "domain level {dl}:\n"
                "\tFor domain level >= 1 replica installation, first join the "
                "domain by running ipa-client-install, then run "
                "ipa-replica-install without a replica file."
                .format(dl=domain_level)
            )

        # Check authorization
        result = remote_api.Command['hostgroup_find'](
            cn=u'ipaservers',
            host=[unicode(api.env.host)]
        )['result']
        add_to_ipaservers = not result

        if add_to_ipaservers:
            if options.password and not options.admin_password:
                raise errors.ACIError(info="Not authorized")

            if installer._ccache is None:
                del os.environ['KRB5CCNAME']
            else:
                os.environ['KRB5CCNAME'] = installer._ccache

            try:
                installutils.check_creds(options, config.realm_name)
                installer._ccache = os.environ.get('KRB5CCNAME')
            finally:
                os.environ['KRB5CCNAME'] = ccache

            conn.disconnect()
            conn.connect(ccache=installer._ccache)

            try:
                result = remote_api.Command['hostgroup_show'](
                    u'ipaservers',
                    all=True,
                    rights=True
                )['result']

                if 'w' not in result['attributelevelrights']['member']:
                    raise errors.ACIError(info="Not authorized")
            finally:
                conn.disconnect()
                conn.connect(ccache=ccache)


        # Check that we don't already have a replication agreement
        if replman.get_replication_agreement(config.host_name):
            msg = ("A replication agreement for this host already exists. "
                   "It needs to be removed.\n"
                   "Run this command:\n"
                   "    %% ipa-replica-manage del {host} --force"
                   .format(host=config.host_name))
            raise ScriptError(msg, rval=3)

        # Detect if the other master can handle replication managers
        # cn=replication managers,cn=sysaccounts,cn=etc,$SUFFIX
        dn = DN(('cn', 'replication managers'), ('cn', 'sysaccounts'),
                ('cn', 'etc'), ipautil.realm_to_suffix(config.realm_name))
        try:
            conn.get_entry(dn)
        except errors.NotFound:
            msg = ("The Replication Managers group is not available in "
                   "the domain. Replica promotion requires the use of "
                   "Replication Managers to be able to replicate data. "
                   "Upgrade the peer master or use the ipa-replica-prepare "
                   "command on the master and use a prep file to install "
                   "this replica.")
            root_logger.error(msg)
            raise ScriptError(rval=3)

        dns_masters = remote_api.Object['dnsrecord'].get_dns_masters()
        if dns_masters:
            if not options.no_host_dns:
                root_logger.debug('Check forward/reverse DNS resolution')
                resolution_ok = (
                    check_dns_resolution(config.master_host_name,
                                         dns_masters) and
                    check_dns_resolution(config.host_name, dns_masters))
                if not resolution_ok and installer.interactive:
                    if not ipautil.user_input("Continue?", False):
                        raise ScriptError(rval=0)
        else:
            root_logger.debug('No IPA DNS servers, '
                              'skipping forward/reverse resolution check')

        entry_attrs = conn.get_ipa_config()
        subject_base = entry_attrs.get('ipacertificatesubjectbase', [None])[0]
        if subject_base is not None:
            config.subject_base = DN(subject_base)

        # Find if any server has a CA
        ca_host = service.find_providing_server(
                'CA', conn, config.ca_host_name)
        if ca_host is not None:
            config.ca_host_name = ca_host
            ca_enabled = True
            if options.dirsrv_cert_files:
                root_logger.error("Certificates could not be provided when "
                                  "CA is present on some master.")
                raise ScriptError(rval=3)
        else:
            if options.setup_ca:
                root_logger.error("The remote master does not have a CA "
                                  "installed, can't set up CA")
                raise ScriptError(rval=3)
            ca_enabled = False
            if not options.dirsrv_cert_files:
                root_logger.error("Cannot issue certificates: a CA is not "
                                  "installed. Use the --http-cert-file, "
                                  "--dirsrv-cert-file options to provide "
                                  "custom certificates.")
                raise ScriptError(rval=3)

        kra_host = service.find_providing_server(
                'KRA', conn, config.kra_host_name)
        if kra_host is not None:
            config.kra_host_name = kra_host
            kra_enabled = True
        else:
            if options.setup_kra:
                root_logger.error("There is no KRA server in the domain, "
                                  "can't setup a KRA clone")
                raise ScriptError(rval=3)
            kra_enabled = False

        if ca_enabled:
            options.realm_name = config.realm_name
            options.host_name = config.host_name
            ca.install_check(False, config, options)

        if kra_enabled:
            try:
                kra.install_check(remote_api, config, options)
            except RuntimeError as e:
                raise ScriptError(e)

        if options.setup_dns:
            dns.install_check(False, remote_api, True, options,
                              config.host_name)
            config.ips = dns.ip_addresses
        else:
            config.ips = installutils.get_server_ip_address(
                config.host_name, not installer.interactive,
                False, options.ip_addresses)

            # check addresses here, dns module is doing own check
            network_ip_address_warning(config.ips)
            broadcast_ip_address_warning(config.ips)

        if options.setup_adtrust:
            adtrust.install_check(False, options, remote_api)

    except errors.ACIError:
        root_logger.debug(traceback.format_exc())
        raise ScriptError("\nInsufficient privileges to promote the server."
                          "\nPossible issues:"
                          "\n- A user has insufficient privileges"
                          "\n- This client has insufficient privileges "
                          "to become an IPA replica")
    except errors.LDAPError:
        root_logger.debug(traceback.format_exc())
        raise ScriptError("\nUnable to connect to LDAP server %s" %
                          config.master_host_name)
    finally:
        if replman and replman.conn:
            replman.conn.unbind()
        if conn.isconnected():
            conn.disconnect()

    # check connection
    if not options.skip_conncheck:
        if add_to_ipaservers:
            # use user's credentials when the server host is not ipaservers
            if installer._ccache is None:
                del os.environ['KRB5CCNAME']
            else:
                os.environ['KRB5CCNAME'] = installer._ccache

        try:
            replica_conn_check(
                config.master_host_name, config.host_name, config.realm_name,
                options.setup_ca, 389,
                options.admin_password, principal=options.principal,
                ca_cert_file=cafile)
        finally:
            if add_to_ipaservers:
                os.environ['KRB5CCNAME'] = ccache

    installer._ca_enabled = ca_enabled
    installer._kra_enabled = kra_enabled
    installer._ca_file = cafile
    installer._fstore = fstore
    installer._sstore = sstore
    installer._config = config
    installer._add_to_ipaservers = add_to_ipaservers
    installer._dirsrv_pkcs12_file = dirsrv_pkcs12_file
    installer._dirsrv_pkcs12_info = dirsrv_pkcs12_info
    installer._http_pkcs12_file = http_pkcs12_file
    installer._http_pkcs12_info = http_pkcs12_info
    installer._pkinit_pkcs12_file = pkinit_pkcs12_file
    installer._pkinit_pkcs12_info = pkinit_pkcs12_info


@common_cleanup
def install(installer):
    options = installer
    ca_enabled = installer._ca_enabled
    kra_enabled = installer._kra_enabled
    fstore = installer._fstore
    sstore = installer._sstore
    config = installer._config
    promote = installer.promote
    cafile = installer._ca_file
    dirsrv_pkcs12_info = installer._dirsrv_pkcs12_info
    http_pkcs12_info = installer._http_pkcs12_info

    remote_api = installer._remote_api
    conn = remote_api.Backend.ldap2
    ccache = os.environ['KRB5CCNAME']

    # Make sure tmpfiles dir exist before installing components
    create_ipaapi_user()
    tasks.create_tmpfiles_dirs()

    if promote:
        if installer._add_to_ipaservers:
            try:
                conn.connect(ccache=installer._ccache)
                remote_api.Command['hostgroup_add_member'](
                    u'ipaservers',
                    host=[unicode(api.env.host)],
                )
            finally:
                if conn.isconnected():
                    conn.disconnect()
                os.environ['KRB5CCNAME'] = ccache
        config.dirman_password = ipautil.ipa_generate_password()

        # FIXME: allow to use passed in certs instead
        if ca_enabled:
            configure_certmonger()
    elif installer._update_hosts_file:
        installutils.update_hosts_file(config.ips, config.host_name, fstore)

    # Configure ntpd
    if not options.no_ntp:
        ipaclient.install.ntpconf.force_ntpd(sstore)
        ntp = ntpinstance.NTPInstance()
        ntp.create_instance()

    dsinstance.create_ds_user()

    try:
        conn.connect(ccache=ccache)
        # Update and istall updated CA file
        cafile = install_ca_cert(conn, api.env.basedn, api.env.realm, cafile)

        # Configure dirsrv
        ds = install_replica_ds(config, options, ca_enabled,
                                remote_api,
                                ca_file=cafile,
                                promote=promote,
                                pkcs12_info=dirsrv_pkcs12_info)

        # Always try to install DNS records
        install_dns_records(config, options, remote_api)

        if promote and ca_enabled:
            # we need to install http certs to setup ssl for httpd
            install_http_certs(config.host_name,
                               config.realm_name,
                               config.subject_base)

        ntpinstance.ntp_ldap_enable(config.host_name, ds.suffix,
                                    remote_api.env.realm)
    finally:
        if conn.isconnected():
            conn.disconnect()

        if promote:
            # Create the management framework config file. Do this irregardless
            # of the state of DS installation. Even if it fails,
            # we need to have master-like configuration in order to perform a
            # successful uninstallation
            # The configuration creation has to be here otherwise previous call
            # To config certmonger would try to connect to local server
            create_ipa_conf(fstore, config, ca_enabled)

    krb = install_krb(
        config,
        setup_pkinit=not options.no_pkinit,
        promote=promote)

    # restart DS to enable ipa-pwd-extop plugin
    print("Restarting directory server to enable password extension plugin")
    ds.restart()

    install_http(
        config,
        auto_redirect=not options.no_ui_redirect,
        promote=promote,
        pkcs12_info=http_pkcs12_info,
        ca_is_configured=ca_enabled,
        ca_file=cafile)

    otpd = otpdinstance.OtpdInstance()
    otpd.create_instance('OTPD', config.host_name,
                         ipautil.realm_to_suffix(config.realm_name))

    custodia = custodiainstance.CustodiaInstance(config.host_name,
                                                 config.realm_name)
    if promote:
        custodia.create_replica(config.master_host_name)
    else:
        custodia.create_instance()

    if ca_enabled:
        options.realm_name = config.realm_name
        options.domain_name = config.domain_name
        options.host_name = config.host_name
        options.dm_password = config.dirman_password
        ca.install(False, config, options)

    # Apply any LDAP updates. Needs to be done after the replica is synced-up
    service.print_msg("Applying LDAP updates")
    ds.apply_updates()

    if kra_enabled:
        kra.install(api, config, options)

    service.print_msg("Restarting the KDC")
    krb.restart()

    if promote:
        custodia.import_dm_password(config.master_host_name)
        promote_sssd(config.host_name)
        promote_openldap_conf(config.host_name, config.master_host_name)

    if options.setup_dns:
        dns.install(False, True, options, api)
    else:
        api.Command.dns_update_system_records()

    if options.setup_adtrust:
        adtrust.install(False, options, fstore, api)

    api.Backend.ldap2.disconnect()

    if not promote:
        # Call client install script
        service.print_msg("Configuring client side components")
        try:
            args = [paths.IPA_CLIENT_INSTALL, "--on-master", "--unattended",
                    "--domain", config.domain_name,
                    "--server", config.host_name,
                    "--realm", config.realm_name, "--no-ntp"]
            if options.no_dns_sshfp:
                args.append("--no-dns-sshfp")
            if options.ssh_trust_dns:
                args.append("--ssh-trust-dns")
            if options.no_ssh:
                args.append("--no-ssh")
            if options.no_sshd:
                args.append("--no-sshd")
            if options.mkhomedir:
                args.append("--mkhomedir")
            ipautil.run(args, redirect_output=True)
            print()
        except Exception:
            print("Configuration of client side components failed!")
            raise RuntimeError("Failed to configure the client")

        # remove the extracted replica file
        remove_replica_info_dir(installer)

    # Everything installed properly, activate ipa service.
    services.knownservices.ipa.enable()


def init(installer):
    installer.unattended = not installer.interactive
    installer.promote = installer.replica_file is None

    if installer.servers:
        installer.server = installer.servers[0]
    else:
        installer.server = None
    if installer.replica_file is None:
        installer.password = installer.host_password
    else:
        installer.password = installer.dm_password

    installer._ccache = os.environ.get('KRB5CCNAME')

    installer._top_dir = None
    installer._config = None
    installer._update_hosts_file = False
    installer._dirsrv_pkcs12_file = None
    installer._http_pkcs12_file = None
    installer._pkinit_pkcs12_file = None
    installer._dirsrv_pkcs12_info = None
    installer._http_pkcs12_info = None
    installer._pkinit_pkcs12_info = None