I don't know of any Canon-made extension tubes.
Canon makes two, the EF12 and EF25.
IMO while they are expensive relative to aftermarket brandes, they are not all that expensive as quality accessories. They are very well made, provide full connectivity between Canon cameras and lenses and mount/dismount smoothly. Plus they are strong enough to use with long lenses mounted to the tripod having the body hanging off the rear of the lens by the tube. (Why do I do this some may wonder -- to provide extra close focusing for small mammals and birds when using he long lenses.)
The biggest gripe I have heard with the aftermarket tubes is the camera and lens mounts are not smooth, followed by connectivity issues...