Masks the token on the left with the token on the right.

Both tokens are required to have the same size.

Compares the two binaries (one being masked) in constant-time to avoid timing attacks.

It is assumed the right token is masked according to the given mask.

Compares the two binaries in constant-time to avoid timing attacks.

See: http://codahale.com/a-lesson-in-timing-attacks/