Using B1 account details in an asp,net application

Hi

I have developed an ASP.net application that allows employees to fill in worksheets documenting what they have been doing when. At the moment it has a login that query's the users input with a table within a database separate to the B1 database. What I was hoping to do was to allow the users of the worksheet to use their B1 username and password, which I think is attained from the OUSR table. Would this be possible, and if so how could it be done?

Thanks

Steve