Allow HTTPd user to access SSSD IFP

For smart card and certificate authentication, Apache's
mod_lookup_identity module must be able to acess SSSD IFP. The module
accesses IFP as Apache user, not as ipaapi user.

Apache is not allowed to use IFP by default. The update code uses the
service's ok-to-auth-as-delegate flag to detect smart card / cert auth.

See: https://pagure.io/freeipa/issue/7751
Signed-off-by: Christian Heimes <cheimes@redhat.com>
Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>

ipaclient/install/client.py

@@ -45,6 +45,7 @@ from ipalib.util import (
     verify_host_resolvable,
 )
 from ipaplatform import services
+from ipaplatform.constants import constants
 from ipaplatform.paths import paths
 from ipaplatform.tasks import tasks
 from ipapython import certdb, kernel_keyring, ipaldap, ipautil
@@ -1036,8 +1037,13 @@ def sssd_enable_service(sssdconfig, name):
     return sssdconfig.get_service(name)
 
 
-def sssd_enable_ifp(sssdconfig):
+def sssd_enable_ifp(sssdconfig, allow_httpd=False):
     """Enable and configure libsss_simpleifp plugin
+
+    Allow the ``ipaapi`` user to access IFP. In case allow_httpd is true,
+    the Apache HTTPd user is also allowed to access IFP. For smart card
+    authentication, mod_lookup_identity must be allowed to access user
+    information.
     """
     service = sssd_enable_service(sssdconfig, 'ifp')
     if service is None:
@@ -1056,6 +1062,8 @@ def sssd_enable_ifp(sssdconfig):
         uids.add('root')
     # allow IPA API to access IFP
     uids.add(IPAAPI_USER)
+    if allow_httpd:
+        uids.add(constants.HTTPD_USER)
     service.set_option('allowed_uids', ', '.join(sorted(uids)))
     sssdconfig.save_service(service)