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Re: KDE Partition Manager and KPMcore 4.0 beta / KAuth review request / Name of the program

>Then it starts DBus interface where the
original GUI program can request execution of various partitioning commands as root. These requests are
RSA signed by the GUI program and come with a cryptographic nonce which prevents replaying them.

You can correctly identify the sender of the gui app that spawned us and you can verify that any new requests are from that sender. See QDBusContext.
DBus base service names are always unique and not something that could be faked on the system bus.