Use GSSAPI auth for the ipa-replica-manage list and del commands.

This creates a new role, replicaadmin, so a non-DM user can do
limited management of replication agreements.

Note that with cn=config if an unauthorized user performs a search
an error is not returned, no entries are returned. This makes it
difficult to determine if there are simply no replication agreements or
we aren't allowed to see them. Once the ipaldap.py module gets
replaced by ldap2 we can use Get Effective Rights to easily tell the
difference.

ipaserver/install/replication.py

@@ -38,6 +38,8 @@ TIMEOUT = 120
 IPA_REPLICA = 1
 WINSYNC = 2
 
+SASL_AUTH = ldap.sasl.sasl({}, 'GSSAPI')
+
 class ReplicationManager:
     """Manage replication agreements between DS servers, and sync
     agreements with Windows servers"""
@@ -45,8 +47,13 @@ class ReplicationManager:
         self.hostname = hostname
         self.dirman_passwd = dirman_passwd
 
+        # If we are passed a password we'll use it as the DM password
+        # otherwise we'll do a GSSAPI bind.
         self.conn = ipaldap.IPAdmin(hostname, port=PORT, cacert=CACERT)
-        self.conn.do_simple_bind(bindpw=dirman_passwd)
+        if dirman_passwd:
+            self.conn.do_simple_bind(bindpw=dirman_passwd)
+        else:
+            self.conn.sasl_interactive_bind_s('', SASL_AUTH)
 
         self.repl_man_passwd = dirman_passwd
 
@@ -98,6 +105,16 @@ class ReplicationManager:
         return retval
 
     def find_replication_dns(self, conn):
+        """
+        The replication agreements are stored in
+        cn="$SUFFIX",cn=mapping tree,cn=config
+
+        FIXME: Rather than failing with a read error if a user tries
+        to read this it simply returns zero entries. We need to use
+        GER to determine if we are allowed to read this to return a proper
+        response. For now just return "No entries" even if the user may
+        not be allowed to see them.
+        """
         filt = "(|(objectclass=nsDSWindowsReplicationAgreement)(objectclass=nsds5ReplicationAgreement))"
         try:
             ents = conn.search_s("cn=mapping tree,cn=config", ldap.SCOPE_SUBTREE, filt)
@@ -465,6 +482,7 @@ class ReplicationManager:
         # allow connections using two different CA certs
         other_conn = ipaldap.IPAdmin(other_hostname, port=oth_port, cacert=oth_cacert)
         try:
+            # For now we always require a password to set up new replica
             other_conn.do_simple_bind(binddn=oth_binddn, bindpw=oth_bindpw)
         except Exception, e:
             if iswinsync: