Universally composable password-based key exchange

Abstract We propose and realize a definition of security for password-based key exchange within theframework of universal composability (UC), thus providing security guarantees under arbitrary composition with other protocols. In addition, our definition captures some aspects of theproblem that were not adequately addressed by most prior notions. For instance, our definition does not assume any underlying probability distribution on passwords, nor does it assumeindependence between passwords chosen by different parties. We also formulate a definition of password-based secure channels, and show how to realize such channels given any password-based key exchange protocol