Adding new field in Logon Page

Hi Experts,

My requirement is to add a new field in the login page. The field that to be added is Passcode field, so I need the type of field as password. How can I add my new field in the Logon Page and how to validate this field. This validation should be done with respect to database table i.e., ztable.

I have imported WAR file, but in the logonPage.jsp I found the the SAP is using its own tags. Now how can I create the tags as SAP?