transfer to and from location restriction

I want to restrict transfer To and From location as details mentioned below
Have a glimpse of the form given below I have 100 locations. now when initiating a transfer order I want to give permission to users so that user can enter only one permitted location at transfer from location...(may be through security filter)

Now I have created another table where I can specify locations against each user. So that at Transfer To location user can only enter the locations that are specified onto the table against their user id

like if my login user id is "production" ,then I can only enter transfer to locations among that are specified on that table, against the Production User id







I can pick up current user id but compairing the user id with the said table and pick locations that are fixed against the user id ....i cant manage the coding....plz help me out