Authentication with username only

Question

I currently have an MVC website that uses forms authentication using the default SqlMembershipProvider.

In this website I can automatically log a user in by simply having a GUID that corresponds to their UserId in the aspnet_Membership table. All I do is query the table, then using their username I simply have forms authentication set the auth cookie.

I currently use:

FormsAuthentication.RedirectFromLoginPage(username, false)

But can optionally also use:

FormsAuthentication.SetAuthCookie(username, false, "/")

Now, I need to do something similar to this, but on SharePoint. SP does have access to my membership tables.

However, it seems that SP uses SecurityTokens for the validation:

        SecurityToken token = SPSecurityContext.SecurityTokenForFormsAuthentication(new Uri(SPContext.Current.Web.Url), formsClaimsAuthenticationProvider.MembershipProvider, formsClaimsAuthenticationProvider.RoleProvider, strUsername, strPassword);   

        if (null != token)   
        {   
            EstablishSessionWithToken(token);   
            Response.Redirect(strSource);
        }

Questions:

1. Is there a way to get this token by simply providing the username, without the password?
2. Or, can I manually create the SecurityToken to provide to SetPrincipalAndWriteSessionToken()?
3. Or, can I manually set the authentication cookies myself?

Answer 1

It is Forms Authentication and readily supports extension. Simply write a custom membership provider (or even use your current provider) and wire it into SharePoint

Answer 2

Since its forms authentication,

configure it with your existing membership database.

Have a custom login form where you can have user ID alone & follow the below article to proceed further:

[1]http://www.codeproject.com/Articles/165159/Custom-Membership-Providers