Software smart cards via cryptographic camouflage

Abstract

A sensitive point in public key cryptography is how to protect the private key. We outline a method of protecting private keys using cryptographic camouflage. Specifically, we do not encrypt the private key with a password that is too long for exhaustive attack. Instead, we encrypt it so that only one password will decrypt it correctly, but many passwords will decrypt it to produce a key that looks valid enough to fool an attacker. For certain applications, this method protects a private key against dictionary attack, as a smart card does, but entirely in software.