Running on walls

Hello everyone!

I'm hoping to get a little bit of a pointer in the right direction regarding a feature I want in my game..

I'm making a first-person game and I would like for my character to be able to kind of freerun on vertical walls (basically something like Saints Row 4 or Spider-Man 2 or Titanfall)... my main problem with doing this is that I need it to work on uneven walls with things like light window geometry and I don't want my character to be getting hitched up on all of these edges.

P.S. I'm using a custom rigidbody character controller.

Any ideas would be great! Thanks in advance!