Brakes locked up
 

I have a 2001 Toyota Camry. I had the brakes lock up completely in it yesterday when I was leaving my driveway. I would push the pedal down and the brakes wouldn't release. The pedal would come back up, but the pedal itself has springs to make it return. It was all 4 brakes or definately at least the front 2. I would push the pedal down and it felt really soft until it hit the point in the pedals travel where the brakes were stuck at. I was automatically assuming the master cylinder, but I wanted to see if anyone else had any experience with this problem. To add a side note to this issue, for the past couple months, there's been a "creaking" noise when you would push the pedal down almost like the sound from when you open a door that needs greasing. I had thought this was just something to do with the pivot for the actual pedal. Now I'm thinking it was something internally in the master cylinder. Any help would be appreciated.