Turn Kerberos-related properties to Service class members

The Service class now accepts keytab path and service name part of Kerberos
principal as members. Kerberos principal is turned into a property computed
from service prefix, FQDN and realm. the handling of Kerberos principals and
keytabs in service installers was changed to use class members instead of
copy-pasted constants. This shall aid in the future refactoring of
principal/keytab handling code.

https://fedorahosted.org/freeipa/ticket/6392

Reviewed-By: Stanislav Laznicka <slaznick@redhat.com>

9 files changed, 95 insertions, 74 deletions

diff --git a/ipaserver/install/adtrustinstance.py b/ipaserver/install/adtrustinstance.py
index 95988498c..cab5a7239 100644
--- a/ipaserver/install/adtrustinstance.py
+++ b/ipaserver/install/adtrustinstance.py
@@ -136,7 +136,8 @@ class ADTRUSTInstance(service.Service):
         self.host_netbios_name = None
 
         super(ADTRUSTInstance, self).__init__(
-            "smb", service_desc="CIFS", fstore=fstore)
+            "smb", service_desc="CIFS", fstore=fstore, service_prefix=u'cifs',
+            keytab=paths.SAMBA_KEYTAB)
 
         self.__setup_default_attributes()
 
@@ -148,7 +149,6 @@ class ADTRUSTInstance(service.Service):
 
         # Constants
         self.smb_conf = paths.SMB_CONF
-        self.samba_keytab = paths.SAMBA_KEYTAB
         self.cifs_hosts = []
 
         # Values obtained from API.env
@@ -156,7 +156,6 @@ class ADTRUSTInstance(service.Service):
         self.host_netbios_name = make_netbios_name(self.fqdn)
         self.realm = self.realm or api.env.realm
 
-        self.cifs_principal = "cifs/" + self.fqdn + "@" + self.realm
         self.suffix = ipautil.realm_to_suffix(self.realm)
         self.ldapi_socket = "%%2fvar%%2frun%%2fslapd-%s.socket" % \
                             installutils.realm_to_serverid(self.realm)
@@ -173,7 +172,7 @@ class ADTRUSTInstance(service.Service):
                              api.env.container_cifsdomains,
                              self.suffix)
 
-        self.cifs_agent = DN(('krbprincipalname', self.cifs_principal.lower()),
+        self.cifs_agent = DN(('krbprincipalname', self.principal.lower()),
                              api.env.container_service,
                              self.suffix)
         self.host_princ = DN(('fqdn', self.fqdn),
@@ -494,8 +493,8 @@ class ADTRUSTInstance(service.Service):
         try:
             current = self.admin_conn.get_entry(targets_dn)
             members = current.get('memberPrincipal', [])
-            if not(self.cifs_principal in members):
-                current["memberPrincipal"] = members + [self.cifs_principal]
+            if not(self.principal in members):
+                current["memberPrincipal"] = members + [self.principal]
                 self.admin_conn.update_entry(current)
             else:
                 self.print_msg('cifs principal already targeted, nothing to do.')
@@ -530,7 +529,7 @@ class ADTRUSTInstance(service.Service):
 
     def __setup_principal(self):
         try:
-            api.Command.service_add(unicode(self.cifs_principal))
+            api.Command.service_add(unicode(self.principal))
         except errors.DuplicateEntry:
             # CIFS principal already exists, it is not the first time
             # adtrustinstance is managed
@@ -544,21 +543,21 @@ class ADTRUSTInstance(service.Service):
 
         try:
             ipautil.run(["ipa-getkeytab", "--server", self.fqdn,
-                                          "--principal", self.cifs_principal,
-                                          "-k", self.samba_keytab])
+                                          "--principal", self.principal,
+                                          "-k", self.keytab])
         except ipautil.CalledProcessError:
             root_logger.critical("Failed to add key for %s"
-                                 % self.cifs_principal)
+                                 % self.principal)
 
     def clean_samba_keytab(self):
-        if os.path.exists(self.samba_keytab):
+        if os.path.exists(self.keytab):
             try:
-                ipautil.run(["ipa-rmkeytab", "--principal", self.cifs_principal,
-                                         "-k", self.samba_keytab])
+                ipautil.run(["ipa-rmkeytab", "--principal", self.principal,
+                             "-k", self.keytab])
             except ipautil.CalledProcessError as e:
                 if e.returncode != 5:
                     root_logger.critical("Failed to remove old key for %s"
-                                         % self.cifs_principal)
+                                         % self.principal)
 
     def srv_rec(self, host, port, prio):
         return "%(prio)d 100 %(port)d %(host)s" % dict(host=host,prio=prio,port=port)
diff --git a/ipaserver/install/bindinstance.py b/ipaserver/install/bindinstance.py
index bdafd0ff6..d32ced7a6 100644
--- a/ipaserver/install/bindinstance.py
+++ b/ipaserver/install/bindinstance.py
@@ -620,7 +620,9 @@ class BindInstance(service.Service):
             service_desc="DNS",
             fstore=fstore,
             api=api,
-            service_user=constants.NAMED_USER
+            service_user=constants.NAMED_USER,
+            service_prefix=u'DNS',
+            keytab=paths.NAMED_KEYTAB
         )
         self.dns_backup = DnsBackup(self)
         self.domain = None
@@ -778,7 +780,7 @@ class BindInstance(service.Service):
             BINDKEYS_FILE=paths.NAMED_BINDKEYS_FILE,
             MANAGED_KEYS_DIR=paths.NAMED_MANAGED_KEYS_DIR,
             ROOT_KEY=paths.NAMED_ROOT_KEY,
-            NAMED_KEYTAB=paths.NAMED_KEYTAB,
+            NAMED_KEYTAB=self.keytab,
             RFC1912_ZONES=paths.NAMED_RFC1912_ZONES,
             NAMED_PID=paths.NAMED_PID,
             NAMED_VAR_DIR=paths.NAMED_VAR_DIR,
@@ -875,24 +877,23 @@ class BindInstance(service.Service):
             self.__add_master_records(fqdn, addrs)
 
     def __setup_principal(self):
-        dns_principal = "DNS/" + self.fqdn + "@" + self.realm
-        installutils.kadmin_addprinc(dns_principal)
+        installutils.kadmin_addprinc(self.principal)
 
         # Store the keytab on disk
-        self.fstore.backup_file(paths.NAMED_KEYTAB)
-        installutils.create_keytab(paths.NAMED_KEYTAB, dns_principal)
-        p = self.move_service(dns_principal)
+        self.fstore.backup_file(self.keytab)
+        installutils.create_keytab(self.keytab, self.principal)
+        p = self.move_service(self.principal)
         if p is None:
             # the service has already been moved, perhaps we're doing a DNS reinstall
-            dns_principal = DN(('krbprincipalname', dns_principal),
+            dns_principal = DN(('krbprincipalname', self.principal),
                                ('cn', 'services'), ('cn', 'accounts'), self.suffix)
         else:
             dns_principal = p
 
         # Make sure access is strictly reserved to the named user
         pent = pwd.getpwnam(self.service_user)
-        os.chown(paths.NAMED_KEYTAB, pent.pw_uid, pent.pw_gid)
-        os.chmod(paths.NAMED_KEYTAB, 0o400)
+        os.chown(self.keytab, pent.pw_uid, pent.pw_gid)
+        os.chmod(self.keytab, 0o400)
 
         # modify the principal so that it is marked as an ipa service so that
         # it can host the memberof attribute, then also add it to the
@@ -1188,5 +1189,5 @@ class BindInstance(service.Service):
         if named_regular_running:
             self.named_regular.start()
 
-        installutils.remove_keytab(paths.NAMED_KEYTAB)
+        installutils.remove_keytab(self.keytab)
         installutils.remove_ccache(run_as=self.service_user)
diff --git a/ipaserver/install/cainstance.py b/ipaserver/install/cainstance.py
index 9e257b805..4953ff7a0 100644
--- a/ipaserver/install/cainstance.py
+++ b/ipaserver/install/cainstance.py
@@ -302,6 +302,7 @@ class CAInstance(DogtagInstance):
             subsystem="CA",
             service_desc="certificate server",
             host_name=host_name,
+            service_prefix=ipalib.constants.PKI_GSSAPI_SERVICE_NAME,
         )
 
         # for external CAs
@@ -323,6 +324,8 @@ class CAInstance(DogtagInstance):
         self.requestId = None
         self.log = log_mgr.get_logger(self)
         self.no_db_setup = False
+        self.keytab = os.path.join(
+            paths.PKI_TOMCAT, self.service_prefix + '.keytab')
 
     def configure_instance(self, host_name, dm_password, admin_password,
                            pkcs12_info=None, master_host=None, csr_file=None,
@@ -1229,23 +1232,19 @@ class CAInstance(DogtagInstance):
         sysupgrade.set_upgrade_state('dogtag', 'setup_lwca_key_retieval', True)
 
     def __setup_lightweight_ca_key_retrieval_kerberos(self):
-        service = ipalib.constants.PKI_GSSAPI_SERVICE_NAME
-        principal = '{}/{}@{}'.format(service, api.env.host, self.realm)
         pent = pwd.getpwnam(self.service_user)
 
         root_logger.info('Creating principal')
-        installutils.kadmin_addprinc(principal)
+        installutils.kadmin_addprinc(self.principal)
         self.suffix = ipautil.realm_to_suffix(self.realm)
-        self.move_service(principal)
+        self.move_service(self.principal)
 
         root_logger.info('Retrieving keytab')
-        keytab = os.path.join(paths.PKI_TOMCAT, service + '.keytab')
-        installutils.create_keytab(keytab, principal)
-        os.chmod(keytab, 0o600)
-        os.chown(keytab, pent.pw_uid, pent.pw_gid)
+        installutils.create_keytab(self.keytab, self.principal)
+        os.chmod(self.keytab, 0o600)
+        os.chown(self.keytab, pent.pw_uid, pent.pw_gid)
 
     def __setup_lightweight_ca_key_retrieval_custodia(self):
-        service = ipalib.constants.PKI_GSSAPI_SERVICE_NAME
         pent = pwd.getpwnam(self.service_user)
 
         root_logger.info('Creating Custodia keys')
@@ -1261,9 +1260,9 @@ class CAInstance(DogtagInstance):
             objectclass=['top', 'nsContainer'],
             cn=['dogtag'],
         )
-        keyfile = os.path.join(paths.PKI_TOMCAT, service + '.keys')
+        keyfile = os.path.join(paths.PKI_TOMCAT, self.service_prefix + '.keys')
         keystore = IPAKEMKeys({'server_keys': keyfile})
-        keystore.generate_keys(service)
+        keystore.generate_keys(self.service_prefix)
         os.chmod(keyfile, 0o600)
         os.chown(keyfile, pent.pw_uid, pent.pw_gid)
 
diff --git a/ipaserver/install/dnskeysyncinstance.py b/ipaserver/install/dnskeysyncinstance.py
index bcbeeec44..656242b3f 100644
--- a/ipaserver/install/dnskeysyncinstance.py
+++ b/ipaserver/install/dnskeysyncinstance.py
@@ -64,7 +64,9 @@ class DNSKeySyncInstance(service.Service):
         super(DNSKeySyncInstance, self).__init__(
             "ipa-dnskeysyncd",
             service_desc="DNS key synchronization service",
-            fstore=fstore
+            fstore=fstore,
+            service_prefix=u'ipa-dnskeysync',
+            keytab=paths.IPA_DNSKEYSYNCD_KEYTAB
         )
         self.logger = logger
         self.extra_config = [u'dnssecVersion 1', ]  # DNSSEC enabled
@@ -406,24 +408,23 @@ class DNSKeySyncInstance(service.Service):
 
     def __setup_principal(self):
         assert self.ods_gid is not None
-        installutils.remove_keytab(paths.IPA_DNSKEYSYNCD_KEYTAB)
-        dnssynckey_principal = "ipa-dnskeysyncd/" + self.fqdn + "@" + self.realm
-        installutils.kadmin_addprinc(dnssynckey_principal)
+        installutils.remove_keytab(self.keytab)
+        installutils.kadmin_addprinc(self.principal)
 
         # Store the keytab on disk
-        installutils.create_keytab(paths.IPA_DNSKEYSYNCD_KEYTAB, dnssynckey_principal)
-        p = self.move_service(dnssynckey_principal)
+        installutils.create_keytab(self.keytab, self.principal)
+        p = self.move_service(self.principal)
         if p is None:
             # the service has already been moved, perhaps we're doing a DNS reinstall
             dnssynckey_principal_dn = DN(
-                ('krbprincipalname', dnssynckey_principal),
+                ('krbprincipalname', self.principal),
                 ('cn', 'services'), ('cn', 'accounts'), self.suffix)
         else:
             dnssynckey_principal_dn = p
 
         # Make sure access is strictly reserved to the named user
-        os.chown(paths.IPA_DNSKEYSYNCD_KEYTAB, 0, self.ods_gid)
-        os.chmod(paths.IPA_DNSKEYSYNCD_KEYTAB, 0o440)
+        os.chown(self.keytab, 0, self.ods_gid)
+        os.chmod(self.keytab, 0o440)
 
         dns_group = DN(('cn', 'DNS Servers'), ('cn', 'privileges'),
                        ('cn', 'pbac'), self.suffix)
@@ -487,4 +488,4 @@ class DNSKeySyncInstance(service.Service):
         except Exception:
             pass
 
-        installutils.remove_keytab(paths.IPA_DNSKEYSYNCD_KEYTAB)
+        installutils.remove_keytab(self.keytab)
diff --git a/ipaserver/install/dogtaginstance.py b/ipaserver/install/dogtaginstance.py
index cf1e5e078..5d25e42d8 100644
--- a/ipaserver/install/dogtaginstance.py
+++ b/ipaserver/install/dogtaginstance.py
@@ -108,14 +108,15 @@ class DogtagInstance(service.Service):
     server_cert_name = None
 
     def __init__(self, realm, subsystem, service_desc, host_name=None,
-                 nss_db=paths.PKI_TOMCAT_ALIAS_DIR):
+                 nss_db=paths.PKI_TOMCAT_ALIAS_DIR, service_prefix=None):
         """Initializer"""
 
         super(DogtagInstance, self).__init__(
             'pki-tomcatd',
             service_desc=service_desc,
             realm_name=realm,
-            service_user=constants.PKI_USER
+            service_user=constants.PKI_USER,
+            service_prefix=service_prefix
         )
 
         self.admin_password = None
diff --git a/ipaserver/install/dsinstance.py b/ipaserver/install/dsinstance.py
index d26f8380c..7c5cf92c1 100644
--- a/ipaserver/install/dsinstance.py
+++ b/ipaserver/install/dsinstance.py
@@ -227,6 +227,8 @@ class DsInstance(service.Service):
             "dirsrv",
             service_desc="directory server",
             fstore=fstore,
+            service_prefix=u'ldap',
+            keytab=paths.DS_KEYTAB,
             service_user=DS_USER,
             realm_name=realm_name
         )
@@ -308,7 +310,6 @@ class DsInstance(service.Service):
         self.fqdn = fqdn
         self.dm_password = dm_password
         self.domain = domain_name
-        self.principal = "ldap/%s@%s" % (self.fqdn, self.realm)
         self.subject_base = subject_base
         self.idstart = idstart
         self.idmax = idmax
@@ -1225,26 +1226,26 @@ class DsInstance(service.Service):
 
     def __get_ds_keytab(self):
 
-        self.fstore.backup_file(paths.DS_KEYTAB)
+        self.fstore.backup_file(self.keytab)
         try:
-            os.unlink(paths.DS_KEYTAB)
+            os.unlink(self.keytab)
         except OSError:
             pass
 
         installutils.install_service_keytab(self.api,
                                             self.principal,
                                             self.master_fqdn,
-                                            paths.DS_KEYTAB,
+                                            self.keytab,
                                             force_service_add=True)
 
         # Configure DS to use the keytab
-        vardict = {"KRB5_KTNAME": paths.DS_KEYTAB}
+        vardict = {"KRB5_KTNAME": self.keytab}
         ipautil.config_replace_variables(paths.SYSCONFIG_DIRSRV,
                                          replacevars=vardict)
 
         # Keytab must be owned by DS itself
         pent = pwd.getpwnam(self.service_user)
-        os.chown(paths.DS_KEYTAB, pent.pw_uid, pent.pw_gid)
+        os.chown(self.keytab, pent.pw_uid, pent.pw_gid)
 
     def __get_ds_cert(self):
         subject = self.subject_base or DN(('O', self.realm))
diff --git a/ipaserver/install/httpinstance.py b/ipaserver/install/httpinstance.py
index 2869116af..25d16f28e 100644
--- a/ipaserver/install/httpinstance.py
+++ b/ipaserver/install/httpinstance.py
@@ -124,7 +124,9 @@ class HTTPInstance(service.Service):
             "httpd",
             service_desc="the web interface",
             fstore=fstore,
-            service_user=HTTPD_USER)
+            service_prefix=u'HTTP',
+            service_user=HTTPD_USER,
+            keytab=paths.IPA_KEYTAB)
 
         self.cert_nickname = cert_nickname
         self.ca_is_configured = True
@@ -139,7 +141,6 @@ class HTTPInstance(service.Service):
         self.domain = domain_name
         self.suffix = ipautil.realm_to_suffix(self.realm)
         self.pkcs12_info = pkcs12_info
-        self.principal = "HTTP/%s@%s" % (self.fqdn, self.realm)
         self.dercert = None
         self.subject_base = subject_base
         self.sub_dict = dict(
@@ -202,9 +203,9 @@ class HTTPInstance(service.Service):
 
     def __create_http_keytab(self):
         if not self.promote:
-            installutils.remove_keytab(paths.IPA_KEYTAB)
+            installutils.remove_keytab(self.keytab)
             installutils.kadmin_addprinc(self.principal)
-            installutils.create_keytab(paths.IPA_KEYTAB, self.principal)
+            installutils.create_keytab(self.keytab, self.principal)
             self.move_service(self.principal)
 
         pent = pwd.getpwnam(self.service_user)
@@ -527,7 +528,7 @@ class HTTPInstance(service.Service):
             except ValueError as error:
                 root_logger.debug(error)
 
-        installutils.remove_keytab(paths.IPA_KEYTAB)
+        installutils.remove_keytab(self.keytab)
         installutils.remove_ccache(ccache_path=paths.KRB5CC_HTTPD,
                                    run_as=self.service_user)
 
diff --git a/ipaserver/install/odsexporterinstance.py b/ipaserver/install/odsexporterinstance.py
index a53ebe667..7caf27adb 100644
--- a/ipaserver/install/odsexporterinstance.py
+++ b/ipaserver/install/odsexporterinstance.py
@@ -24,7 +24,9 @@ class ODSExporterInstance(service.Service):
         super(ODSExporterInstance, self).__init__(
             "ipa-ods-exporter",
             service_desc="IPA OpenDNSSEC exporter daemon",
-            fstore=fstore
+            fstore=fstore,
+            keytab=paths.IPA_ODS_EXPORTER_KEYTAB,
+            service_prefix=u'ipa-ods-exporter'
         )
         self.ods_uid = None
         self.ods_gid = None
@@ -81,29 +83,29 @@ class ODSExporterInstance(service.Service):
     def __setup_principal(self):
         assert self.ods_uid is not None
 
-        for f in [paths.IPA_ODS_EXPORTER_CCACHE, paths.IPA_ODS_EXPORTER_KEYTAB]:
+        for f in [paths.IPA_ODS_EXPORTER_CCACHE, self.keytab]:
             try:
                 os.remove(f)
             except OSError:
                 pass
 
-        dns_exporter_principal = "ipa-ods-exporter/" + self.fqdn + "@" + self.realm
-        installutils.kadmin_addprinc(dns_exporter_principal)
+        installutils.kadmin_addprinc(self.principal)
 
         # Store the keytab on disk
-        installutils.create_keytab(paths.IPA_ODS_EXPORTER_KEYTAB, dns_exporter_principal)
-        p = self.move_service(dns_exporter_principal)
+        installutils.create_keytab(paths.IPA_ODS_EXPORTER_KEYTAB,
+                                   self.principal)
+        p = self.move_service(self.principal)
         if p is None:
             # the service has already been moved, perhaps we're doing a DNS reinstall
             dns_exporter_principal_dn = DN(
-                ('krbprincipalname', dns_exporter_principal),
+                ('krbprincipalname', self.principal),
                 ('cn', 'services'), ('cn', 'accounts'), self.suffix)
         else:
             dns_exporter_principal_dn = p
 
         # Make sure access is strictly reserved to the ods user
-        os.chmod(paths.IPA_ODS_EXPORTER_KEYTAB, 0o440)
-        os.chown(paths.IPA_ODS_EXPORTER_KEYTAB, 0, self.ods_gid)
+        os.chmod(self.keytab, 0o440)
+        os.chown(self.keytab, 0, self.ods_gid)
 
         dns_group = DN(('cn', 'DNS Servers'), ('cn', 'privileges'),
                        ('cn', 'pbac'), self.suffix)
@@ -146,10 +148,8 @@ class ODSExporterInstance(service.Service):
         self.start()
 
     def remove_service(self):
-        dns_exporter_principal = ("ipa-ods-exporter/%s@%s" % (self.fqdn,
-                                                              self.realm))
         try:
-            api.Command.service_del(dns_exporter_principal)
+            api.Command.service_del(self.principal)
         except errors.NotFound:
             pass
 
@@ -181,5 +181,5 @@ class ODSExporterInstance(service.Service):
         if signerd_running:
             signerd_service.start()
 
-        installutils.remove_keytab(paths.IPA_ODS_EXPORTER_KEYTAB)
+        installutils.remove_keytab(self.keytab)
         installutils.remove_ccache(ccache_path=paths.IPA_ODS_EXPORTER_CCACHE)
diff --git a/ipaserver/install/service.py b/ipaserver/install/service.py
index 79d6ceb8c..75a1304df 100644
--- a/ipaserver/install/service.py
+++ b/ipaserver/install/service.py
@@ -24,14 +24,20 @@ import datetime
 import traceback
 import tempfile
 
+import six
+
 from ipapython import ipautil, sysrestore
 from ipapython.dn import DN
 from ipapython.ipa_log_manager import root_logger
+from ipapython import kerberos
 from ipalib import api, errors, certstore
 from ipaplatform import services
 from ipaplatform.paths import paths
 
 
+if six.PY3:
+    unicode = str
+
 # The service name as stored in cn=masters,cn=ipa,cn=etc. In the tuple
 # the first value is the *nix service name, the second the start order.
 SERVICE_LIST = {
@@ -132,7 +138,8 @@ def find_providing_server(svcname, conn, host_name=None, api=api):
 class Service(object):
     def __init__(self, service_name, service_desc=None, sstore=None,
                  fstore=None, api=api, realm_name=None,
-                 service_user=None):
+                 service_user=None, service_prefix=None,
+                 keytab=None):
         self.service_name = service_name
         self.service_desc = service_desc
         self.service = services.service(service_name)
@@ -153,7 +160,8 @@ class Service(object):
 
         self.realm = realm_name
         self.suffix = DN()
-        self.principal = None
+        self.service_prefix = service_prefix
+        self.keytab = keytab
         self.dercert = None
         self.api = api
         self.service_user = service_user
@@ -165,6 +173,16 @@ class Service(object):
         """
         return api.Backend.ldap2
 
+    @property
+    def principal(self):
+        if any(attr is None for attr in (self.realm, self.fqdn,
+                                         self.service_prefix)):
+            return
+
+        return unicode(
+            kerberos.Principal(
+                (self.service_prefix, self.fqdn), realm=self.realm))
+
     def _ldap_mod(self, ldif, sub_dict=None, raise_on_err=True,
                   ldap_uri=None, dm_password=None):
         pw_name = None