3
 5a    nt = Rich_Service(attr_value)
                    in_elements.pop() # service
                else:
                    raise FirewallError(errors.INVALID_RULE, "invalid 'service' element")
            elif in_element == 'port':
                if attr_name in ['port', 'protocol']:
                    attrs[attr_name] = attr_value
                else:
                    self.element = Rich_Port(attrs.get('port'), attrs.get('protocol'))
                    in_elements.pop() # port
                    attrs.clear()
                    index = index -1 # return token to input
            elif in_element == 'icmp-block':
                if attr_name == 'name':
                    self.element = Rich_IcmpBlock(attr_value)
                    in_elements.pop() # icmp-block
                else:
                    raise FirewallError(errors.INVALID_RULE, "invalid 'icmp-block' element")
            elif in_element == 'icmp-type':
                if attr_name == 'name':
                    self.element = Rich_IcmpType(attr_value)
                    in_elements.pop() # icmp-type
                else:
                    raise FirewallError(errors.INVALID_RULE, "invalid 'icmp-type' element")
            elif in_element == 'masquerade':
                self.element = Rich_Masquerade()
                in_elements.pop()
                attrs.clear()
                index = index -1 # return token to input
            elif in_element == 'forward-port':
                if attr_name in ['port', 'protocol', 'to-port', 'to-addr']:
                    attrs[attr_name] = attr_value
                else:
                    self.element = Rich_ForwardPort(attrs.get('port'), attrs.get('protocol'), attrs.get('to-port'), attrs.get('to-addr'))
                    in_elements.pop() # forward-port
                    attrs.clear()
                    index = index -1 # return token to input
            elif in_element == 'source-port':
                if attr_name in ['port', 'protocol']:
                    attrs[attr_name] = attr_value
                else:
                    self.element = Rich_SourcePort(attrs.get('port'), attrs.get('protocol'))
                    in_elements.pop() # source-port
                    attrs.clear()
                    index = index -1 # return token to input
            elif in_element == 'log':
                if attr_name in ['prefix', 'level']:
                    attrs[attr_name] = attr_value
                elif element == 'limit':
                    in_elements.append('limit')
                else:
                    self.log = Rich_Log(attrs.get('prefix'), attrs.get('level'), attrs.get('limit'))
                    in_elements.pop() # log
                    attrs.clear()
                    index = index -1 # return token to input
            elif in_element == 'audit':
                if element == 'limit':
                    in_elements.append('limit')
                else:
                    self.audit = Rich_Audit(attrs.get('limit'))
                    in_elements.pop() # audit
                    attrs.clear()
                    index = index -1 # return token to input
            elif in_element == 'accept':
                if element == 'limit':
                    in_elements.append('limit')
                else:
                    self.action = Rich_Accept(attrs.get('limit'))
                    in_elements.pop() # accept
                    attrs.clear()
                    index = index -1 # return token to input
            elif in_element == 'drop':
                if element == 'limit':
                    in_elements.append('limit')
                else:
                    self.action = Rich_Drop(attrs.get('limit'))
                    in_elements.pop() # drop
                    attrs.clear()
                    index = index -1 # return token to input
            elif in_element == 'reject':
                if attr_name == 'type':
                    attrs[attr_name] = attr_value
                elif element == 'limit':
                    in_elements.append('limit