What is the ruling on creating a program that blocks pornographic websites, if this requires passing and writing pornographic words and vulgar phrases into the program's database?

Striving to prevent websites that contain Sharia prohibitions, especially pornographic websites, is obligatory according to one's ability. There is no harm in creating programs that block these websites, as they are necessary for such programs to function, while trying to minimize personal harm to the program designer as much as possible.