2000 Pontiac Montana brakes problems

While driving north on us-57 in illinois, we experienced a failure of our braking system, apparently from a severed brake line. While my wife was driving, we exited the highway at exit #283, gilman, illinois. As we went up the ramp, my wife began braking, and the pedal went all the way to the floor, while barely slowing the vehicle. The brake warning light was not on before this point, but came on after several pumps of the pedal.

When I started the car this morning and stepped on the brake pedal, it went all the way to the floor. Upon inspection, there was a puddle of brake fluid on the driveway under the passenger door on the driver's side. I inspected further with a flashlight and mirror, and could see that the fluid was dripping from a bundle of brake lines attached to the chassis, of which one was severely corroded..