Building a Signing Server

The Android APK signing model sets the expectation that the signing key will be the same for the entire lifetime of the app. That can be seen in the recommended lifetype of an Android signing key: 20+ years. On top of that, it is difficult to migrate an app to a new key. Since the signing key is an essential part to preventing APKs from impersonating another, Android signing keys must be kept safe for the entire life of the app. [Read More]

On Verifying Identity Using Cryptography

One of the most important uses of cryptography these days is verifying the identity of the other side of a digital conversation. That conversation could be between two people using OTR-encrypted IM, a web browser showing a bank website, a Debian Developer uploading a package to the Debian build server, an ssh client logging into an ssh server, and on and on. In all of these cases, cryptography is used to ensure that the software is indeed receiving replies from the expected entity. [Read More]