Officially there is no mouse and keyboard support for neither the Playstation 4, nor the Xbox One, the new current generation home consoles.
Officially is the keyword here…
Modder enables mouse and keyboard support for the PS4
A modder called Frank Zhao has developed some external hardware, which can, if connected with the Playstation 4, enable the support for a computer mouse and a common keyboard for said console.
In his preview video you can see that he is playing the game Battlefield 4 via a mouse and keyboard, instead of a controller. He says that he developed and programmed his external hardware device, which can enable the support for said accessories at every PS4.
Sony has not yet officially enabled support for mice and keyboards at their Playstation 4, but some rumours report that this might be possible in the future.
For more information about this, please visit Franks very own blog, at which he tells a bit more about his mod and how it exactly works.