Migration from authconfig to authselect

The authconfig tool is deprecated and replaced by authselect. Migrate
FreeIPA in order to use the new tool as described in the design page
https://www.freeipa.org/page/V4/Authselect_migration

Fixes:
https://pagure.io/freeipa/issue/7377

Reviewed-By: Alexander Koksharov <akokshar@redhat.com>
Reviewed-By: Florence Blanc-Renaud <frenaud@redhat.com>
Reviewed-By: Christian Heimes <cheimes@redhat.com>

freeipa.spec.in

@@ -597,7 +597,7 @@ Requires: python2-sssdconfig
 Requires: cyrus-sasl-gssapi%{?_isa}
 Requires: chrony
 Requires: krb5-workstation >= %{krb5_version}
-Requires: authconfig
+Requires: authselect >= 0.4-2
 Requires: curl
 # NIS domain name config: /usr/lib/systemd/system/*-domainname.service
 Requires: initscripts

ipaclient/install/client.py

@@ -2036,6 +2036,22 @@ def install_check(options):
             "Invalid hostname, '{}' must not be used.".format(hostname),
             rval=CLIENT_INSTALL_ERROR)
 
+    # --no-sssd is not supported any more for rhel-based distros
+    if not tasks.is_nosssd_supported() and not options.sssd:
+        raise ScriptError(
+            "Option '--no-sssd' is incompatible with the 'authselect' tool "
+            "provided by this distribution for configuring system "
+            "authentication resources",
+            rval=CLIENT_INSTALL_ERROR)
+
+    # --noac is not supported any more for rhel-based distros
+    if not tasks.is_nosssd_supported() and options.no_ac:
+        raise ScriptError(
+            "Option '--noac' is incompatible with the 'authselect' tool "
+            "provided by this distribution for configuring system "
+            "authentication resources",
+            rval=CLIENT_INSTALL_ERROR)
+
     # when installing with '--no-sssd' option, check whether nss-ldap is
     # installed
     if not options.sssd:
@@ -2899,9 +2915,11 @@ def _install(options):
 
     if not options.no_ac:
         # Modify nsswitch/pam stack
-        tasks.modify_nsswitch_pam_stack(sssd=options.sssd,
+        tasks.modify_nsswitch_pam_stack(
+            sssd=options.sssd,
             mkhomedir=options.mkhomedir,
-                                        statestore=statestore)
+            statestore=statestore
+        )
 
         logger.info("%s enabled", "SSSD" if options.sssd else "LDAP")
 

ipaplatform/base/paths.py

@@ -376,6 +376,8 @@ class BasePathNamespace(object):
     IF_INET6 = '/proc/net/if_inet6'
     WSGI_PREFIX_DIR = "/run/httpd/wsgi"
     AUTHCONFIG = None
+    AUTHSELECT = None
+    SYSCONF_NETWORK = None
     IPA_SERVER_UPGRADE = '/usr/sbin/ipa-server-upgrade'
     KEYCTL = '/usr/bin/keyctl'
     GETENT = '/usr/bin/getent'

ipaplatform/base/tasks.py

@@ -135,7 +135,7 @@ class BaseTaskNamespace(object):
 
     def modify_nsswitch_pam_stack(self, sssd, mkhomedir, statestore):
         """
-        If sssd flag is true, configure pam and nsswtich so that SSSD is used
+        If sssd flag is true, configure pam and nsswitch so that SSSD is used
         for retrieving user information and authentication.
 
         Otherwise, configure pam and nsswitch to leverage pure LDAP.
@@ -150,6 +150,13 @@ class BaseTaskNamespace(object):
 
         raise NotImplementedError()
 
+    def is_nosssd_supported(self):
+        """
+        Check if the flag --no-sssd is supported for client install.
+        """
+
+        return True
+
     def backup_auth_configuration(self, path):
         """
         Create backup of access control configuration.
@@ -165,6 +172,12 @@ class BaseTaskNamespace(object):
         """
         raise NotImplementedError()
 
+    def migrate_auth_configuration(self, statestore):
+        """
+        Migrate pam stack configuration to authselect.
+        """
+        return
+
     def set_selinux_booleans(self, required_settings, backup_func=None):
         """Set the specified SELinux booleans
 

ipaplatform/redhat/authconfig.py

@@ -19,6 +19,10 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 from __future__ import absolute_import
+import logging
+import six
+import abc
+import re
 
 from ipaplatform.paths import paths
 from ipapython import ipautil
@@ -27,8 +31,192 @@ import os
 
 FILES_TO_NOT_BACKUP = ['passwd', 'group', 'shadow', 'gshadow']
 
+logger = logging.getLogger(__name__)
 
-class RedHatAuthConfig(object):
+
+def get_auth_tool():
+    return RedHatAuthSelect()
+
+
+@six.add_metaclass(abc.ABCMeta)
+class RedHatAuthToolBase(object):
+
+    @abc.abstractmethod
+    def configure(self, sssd, mkhomedir, statestore):
+        pass
+
+    @abc.abstractmethod
+    def unconfigure(self, fstore, statestore,
+                    was_sssd_installed,
+                    was_sssd_configured):
+        pass
+
+    @abc.abstractmethod
+    def backup(self, path):
+        """
+        Backup the system authentication resources configuration
+        :param path: directory where the backup will be stored
+        """
+        pass
+
+    @abc.abstractmethod
+    def restore(self, path):
+        """
+        Restore the system authentication resources configuration from a backup
+        :param path: directory where the backup is stored
+        """
+        pass
+
+    @abc.abstractmethod
+    def set_nisdomain(self, nisdomain):
+        pass
+
+
+class RedHatAuthSelect(RedHatAuthToolBase):
+
+    def _get_authselect_current_output(self):
+        try:
+            current = ipautil.run(
+                [paths.AUTHSELECT, "current"], env={"LC_ALL": "C.UTF8"})
+        except ipautil.CalledProcessError:
+            logger.debug("Current configuration not managed by authselect")
+            return None
+
+        return current.raw_output.decode()
+
+    def _parse_authselect_output(self, output_text=None):
+        """
+        Parses the output_text to extract the profile and options.
+        When no text is provided, runs the 'authselect profile' command to
+        generate the text to be parsed.
+        """
+        if output_text is None:
+            output_text = self._get_authselect_current_output()
+            if output_text is None:
+                return None
+
+        cfg_params = re.findall(
+            r"\s*Profile ID:\s*(\S+)\s*\n\s*Enabled features:\s*(.*)",
+            output_text,
+            re.DOTALL
+        )
+
+        profile = cfg_params[0][0]
+
+        if not profile:
+            return None
+
+        features = re.findall(r"-\s*(\S+)", cfg_params[0][1], re.DOTALL)
+
+        return profile, features
+
+    def configure(self, sssd, mkhomedir, statestore):
+        # In the statestore, the following keys are used for the
+        # 'authselect' module:
+        # profile: name of the profile configured pre-installation
+        # features_list: lsit of features configured pre-installation
+        # mkhomedir: True if installation was called with --mkhomedir
+        # profile and features_list are used when reverting to the
+        # pre-install state
+        cfg = self._parse_authselect_output()
+        if cfg:
+            statestore.backup_state('authselect', 'profile', cfg[0])
+            statestore.backup_state(
+                    'authselect', 'features_list', " ".join(cfg[1]))
+        else:
+            # cfg = None means that the current conf is not managed by
+            # authselect but by authconfig.
+            # As we are using authselect to configure the host,
+            # it will not be possible to revert to a custom authconfig
+            # configuration later (during uninstall)
+            # Best thing to do will be to use sssd profile at this time
+            logger.warning(
+                "WARNING: The configuration pre-client installation is not "
+                "managed by authselect and cannot be backed up. "
+                "Uninstallation may not be able to revert to the original "
+                "state.")
+
+        cmd = [paths.AUTHSELECT, "select", "sssd"]
+        if mkhomedir:
+            cmd.append("with-mkhomedir")
+            statestore.backup_state('authselect', 'mkhomedir', True)
+        cmd.append("--force")
+
+        ipautil.run(cmd)
+
+    def unconfigure(
+        self, fstore, statestore, was_sssd_installed, was_sssd_configured
+    ):
+        if not statestore.has_state('authselect'):
+            logger.warning(
+                "WARNING: Unable to revert to the pre-installation state "
+                "('authconfig' tool has been deprecated in favor of "
+                "'authselect'). The default sssd profile will be used "
+                "instead.")
+            # Build the equivalent command line that will be displayed
+            # to the user
+            # This is a copy-paste of unconfigure code, except that it
+            # creates the command line but does not actually call it
+            authconfig = RedHatAuthConfig()
+            authconfig.prepare_unconfigure(
+                fstore, statestore, was_sssd_installed, was_sssd_configured)
+            args = authconfig.build_args()
+            logger.warning(
+                "The authconfig arguments would have been: authconfig %s",
+                " ".join(args))
+
+            profile = 'sssd'
+            features = ''
+        else:
+            profile = statestore.restore_state('authselect', 'profile')
+            features = statestore.restore_state('authselect', 'features_list')
+            statestore.delete_state('authselect', 'mkhomedir')
+
+        cmd = [paths.AUTHSELECT, "select", profile, features, "--force"]
+        ipautil.run(cmd)
+
+    def backup(self, path):
+        current = self._get_authselect_current_output()
+        if current is None:
+            return
+
+        if not os.path.exists(path):
+            os.makedirs(path)
+
+        with open(os.path.join(path, "authselect.backup"), 'w') as f:
+            f.write(current)
+
+    def restore(self, path):
+        with open(os.path.join(path, "authselect.backup"), "r") as f:
+            cfg = self._parse_authselect_output(f.read())
+
+        if cfg:
+            profile = cfg[0]
+
+            cmd = [
+                paths.AUTHSELECT, "select", profile,
+                " ".join(cfg[1]), "--force"]
+            ipautil.run(cmd)
+
+    def set_nisdomain(self, nisdomain):
+        try:
+            with open(paths.SYSCONF_NETWORK, 'r') as f:
+                content = [
+                    line for line in f
+                    if not line.strip().upper().startswith('NISDOMAIN')
+                ]
+        except IOError:
+            content = []
+
+        content.append("NISDOMAIN={}\n".format(nisdomain))
+
+        with open(paths.SYSCONF_NETWORK, 'w') as f:
+            f.writelines(content)
+
+
+# RedHatAuthConfig concrete class definition to be removed later
+# when agreed on exact path to migrate to authselect
+class RedHatAuthConfig(RedHatAuthToolBase):
     """
     AuthConfig class implements system-independent interface to configure
     system authentication resources. In Red Hat systems this is done with
@@ -95,6 +283,60 @@ class RedHatAuthConfig(object):
         except ipautil.CalledProcessError:
             raise ScriptError("Failed to execute authconfig command")
 
+    def configure(self, sssd, mkhomedir, statestore):
+        if sssd:
+            statestore.backup_state('authconfig', 'sssd', True)
+            statestore.backup_state('authconfig', 'sssdauth', True)
+            self.enable("sssd")
+            self.enable("sssdauth")
+        else:
+            statestore.backup_state('authconfig', 'ldap', True)
+            self.enable("ldap")
+            self.enable("forcelegacy")
+
+            statestore.backup_state('authconfig', 'krb5', True)
+            self.enable("krb5")
+            self.add_option("nostart")
+
+        if mkhomedir:
+            statestore.backup_state('authconfig', 'mkhomedir', True)
+            self.enable("mkhomedir")
+
+        self.execute()
+        self.reset()
+
+    def prepare_unconfigure(self, fstore, statestore,
+                            was_sssd_installed,
+                            was_sssd_configured):
+        if statestore.has_state('authconfig'):
+            # disable only those configurations that we enabled during install
+            for conf in ('ldap', 'krb5', 'sssd', 'sssdauth', 'mkhomedir'):
+                cnf = statestore.restore_state('authconfig', conf)
+                # Do not disable sssd, as this can cause issues with its later
+                # uses. Remove it from statestore however, so that it becomes
+                # empty at the end of uninstall process.
+                if cnf and conf != 'sssd':
+                    self.disable(conf)
+        else:
+            # There was no authconfig status store
+            # It means the code was upgraded after original install
+            # Fall back to old logic
+            self.disable("ldap")
+            self.disable("krb5")
+            if not(was_sssd_installed and was_sssd_configured):
+                # Only disable sssdauth. Disabling sssd would cause issues
+                # with its later uses.
+                self.disable("sssdauth")
+            self.disable("mkhomedir")
+
+    def unconfigure(self, fstore, statestore,
+                    was_sssd_installed,
+                    was_sssd_configured):
+        self.prepare_unconfigure(
+            fstore, statestore, was_sssd_installed, was_sssd_configured)
+        self.execute()
+        self.reset()
+
     def backup(self, path):
         try:
             ipautil.run([paths.AUTHCONFIG, "--savebackup", path])
@@ -116,3 +358,9 @@ class RedHatAuthConfig(object):
             ipautil.run([paths.AUTHCONFIG, "--restorebackup", path])
         except ipautil.CalledProcessError:
             raise ScriptError("Failed to execute authconfig command")
+
+    def set_nisdomain(self, nisdomain):
+        # Let authconfig setup the permanent configuration
+        self.reset()
+        self.add_parameter("nisdomain", nisdomain)
+        self.execute()

ipaplatform/redhat/paths.py

@@ -37,6 +37,8 @@ class RedHatPathNamespace(BasePathNamespace):
         PAM_KRB5_SO = BasePathNamespace.PAM_KRB5_SO_64
         BIND_LDAP_SO = BasePathNamespace.BIND_LDAP_SO_64
     AUTHCONFIG = '/usr/sbin/authconfig'
+    AUTHSELECT = '/usr/bin/authselect'
+    SYSCONF_NETWORK = '/etc/sysconfig/network'
 
 
 paths = RedHatPathNamespace()

ipaplatform/redhat/tasks.py

@@ -45,7 +45,7 @@ import ipapython.errors
 
 from ipaplatform.constants import constants
 from ipaplatform.paths import paths
-from ipaplatform.redhat.authconfig import RedHatAuthConfig
+from ipaplatform.redhat.authconfig import get_auth_tool
 from ipaplatform.base.tasks import BaseTaskNamespace
 
 logger = logging.getLogger(__name__)
@@ -186,70 +186,67 @@ class RedHatTaskNamespace(BaseTaskNamespace):
                                              was_sssd_installed,
                                              was_sssd_configured):
 
-        auth_config = RedHatAuthConfig()
-        if statestore.has_state('authconfig'):
-            # disable only those configurations that we enabled during install
-            for conf in ('ldap', 'krb5', 'sssd', 'sssdauth', 'mkhomedir'):
-                cnf = statestore.restore_state('authconfig', conf)
-                # Do not disable sssd, as this can cause issues with its later
-                # uses. Remove it from statestore however, so that it becomes
-                # empty at the end of uninstall process.
-                if cnf and conf != 'sssd':
-                    auth_config.disable(conf)
-        else:
-            # There was no authconfig status store
-            # It means the code was upgraded after original install
-            # Fall back to old logic
-            auth_config.disable("ldap")
-            auth_config.disable("krb5")
-            if not(was_sssd_installed and was_sssd_configured):
-                # Only disable sssdauth. Disabling sssd would cause issues
-                # with its later uses.
-                auth_config.disable("sssdauth")
-            auth_config.disable("mkhomedir")
-
-        auth_config.execute()
+        auth_config = get_auth_tool()
+        auth_config.unconfigure(
+            fstore, statestore, was_sssd_installed, was_sssd_configured
+        )
 
     def set_nisdomain(self, nisdomain):
-        # Let authconfig setup the permanent configuration
-        auth_config = RedHatAuthConfig()
-        auth_config.add_parameter("nisdomain", nisdomain)
-        auth_config.execute()
+        try:
+            with open(paths.SYSCONF_NETWORK, 'r') as f:
+                content = [
+                    line for line in f
+                    if not line.strip().upper().startswith('NISDOMAIN')
+                ]
+        except IOError:
+            content = []
+
+        content.append("NISDOMAIN={}\n".format(nisdomain))
+
+        with open(paths.SYSCONF_NETWORK, 'w') as f:
+            f.writelines(content)
 
     def modify_nsswitch_pam_stack(self, sssd, mkhomedir, statestore):
-        auth_config = RedHatAuthConfig()
+        auth_config = get_auth_tool()
+        auth_config.configure(sssd, mkhomedir, statestore)
 
-        if sssd:
-            statestore.backup_state('authconfig', 'sssd', True)
-            statestore.backup_state('authconfig', 'sssdauth', True)
-            auth_config.enable("sssd")
-            auth_config.enable("sssdauth")
-        else:
-            statestore.backup_state('authconfig', 'ldap', True)
-            auth_config.enable("ldap")
-            auth_config.enable("forcelegacy")
-
-        if mkhomedir:
-            statestore.backup_state('authconfig', 'mkhomedir', True)
-            auth_config.enable("mkhomedir")
-
-        auth_config.execute()
-
-    def modify_pam_to_use_krb5(self, statestore):
-        auth_config = RedHatAuthConfig()
-        statestore.backup_state('authconfig', 'krb5', True)
-        auth_config.enable("krb5")
-        auth_config.add_option("nostart")
-        auth_config.execute()
+    def is_nosssd_supported(self):
+        # The flag --no-sssd is not supported any more for rhel-based distros
+        return False
 
     def backup_auth_configuration(self, path):
-        auth_config = RedHatAuthConfig()
+        auth_config = get_auth_tool()
         auth_config.backup(path)
 
     def restore_auth_configuration(self, path):
-        auth_config = RedHatAuthConfig()
+        auth_config = get_auth_tool()
         auth_config.restore(path)
 
+    def migrate_auth_configuration(self, statestore):
+        """
+        Migrate the pam stack configuration from authconfig to an authselect
+        profile.
+        """
+        # Check if mkhomedir was enabled during installation
+        mkhomedir = statestore.get_state('authconfig', 'mkhomedir')
+
+        # Force authselect 'sssd' profile
+        authselect_cmd = [paths.AUTHSELECT, "select", "sssd"]
+        if mkhomedir:
+            authselect_cmd.append("with-mkhomedir")
+        authselect_cmd.append("--force")
+        ipautil.run(authselect_cmd)
+
+        # Remove all remaining keys from the authconfig module
+        for conf in ('ldap', 'krb5', 'sssd', 'sssdauth', 'mkhomedir'):
+            statestore.restore_state('authconfig', conf)
+
+        # Create new authselect module in the statestore
+        statestore.backup_state('authselect', 'profile', 'sssd')
+        statestore.backup_state(
+            'authselect', 'features_list', '')
+        statestore.backup_state('authselect', 'mkhomedir', bool(mkhomedir))
+
     def reload_systemwide_ca_store(self):
         try:
             ipautil.run([paths.UPDATE_CA_TRUST])
@@ -408,7 +405,6 @@ class RedHatTaskNamespace(BaseTaskNamespace):
         if fstore.has_file(filepath):
             fstore.restore_file(filepath)
 
-
     def set_selinux_booleans(self, required_settings, backup_func=None):
         def get_setsebool_args(changes):
             args = [paths.SETSEBOOL, "-P"]

ipaserver/install/server/upgrade.py

@@ -1654,6 +1654,21 @@ def update_replica_config(db_suffix):
         api.Backend.ldap2.update_entry(entry)
 
 
+def migrate_to_authselect():
+    logger.info('[Migrating to authselect profile]')
+    if sysupgrade.get_upgrade_state('authcfg', 'migrated_to_authselect'):
+        logger.info("Already migrated to authselect profile")
+        return
+
+    statestore = sysrestore.StateFile(paths.IPA_CLIENT_SYSRESTORE)
+    try:
+        tasks.migrate_auth_configuration(statestore)
+    except ipautil.CalledProcessError as e:
+        raise RuntimeError(
+            "Failed to migrate to authselect profile: %s" % e, 1)
+    sysupgrade.set_upgrade_state('authcfg', 'migrated_to_authselect', True)
+
+
 def upgrade_configuration():
     """
     Execute configuration upgrade of the IPA services
@@ -1933,6 +1948,7 @@ def upgrade_configuration():
         ca.setup_lightweight_ca_key_retrieval()
         cainstance.ensure_ipa_authority_entry()
 
+    migrate_to_authselect()
     set_sssd_domain_option('ipa_server_mode', 'True')
     set_sssd_domain_option('ipa_server', api.env.host)