DCC Boxed DUIS Signing Tool API
An open-source HTTP API published by Smart DCC Limited for signing and validating DUIS (DCC User Interface Specification) XML messages. Two operations — POST /sign adds an XML digital signature to a Base64-encoded unsigned DUIS request (with an optional preserveCounter flag), and POST /verify validates the signature on a DUIS response and strips it. The tool ships with the ZAZ1 test SMKI certificates used by DCC Boxed and also performs XSD validation. It runs locally as a self-hosted server; Smart DCC operates no public hosted instance.