An integrated circuit comprising: a memory for storing mass storage data; and a microprocessor connected to the memory and operative for initiating communications with a host using a chip/smart card CCID interface in accordance with the International Standards Organization ISO 7816 protocol and transferring mass storage data using a mass storage interface in accordance with the USB mass storage class specification; the integrated circuit characterized by: comprising a USB firmware library and a file system with mass storage firmware and ISO 7816 protocol and CCID protocol firmware, both the mass storage firmware and the CCID protocol firmware operative with the USB firmware library; the microprocessor being operable to: call a first communications session to configure rights of a directory and grant files access using the CCID interface and subsequently transfer mass storage data using the mass storage interface wherein only the granted files are accessible through a host application using the mass storage interface; and support a control endpoint, a bulk-in endpoint and bulk-out endpoint when communicating with a host using a mass storage interface. a memory for storing mass storage data; and a microprocessor connected to the memory and operative for initiating communications with a host using a chip/smart card CCID interface in accordance with the International Standards Organization ISO 7816 protocol and transferring mass storage data using a mass storage interface in accordance with the USB mass storage class specification; the integrated circuit characterized by: comprising a USB firmware library and a file system with mass storage firmware and ISO 7816 protocol and CCID protocol firmware, both the mass storage firmware and the CCID protocol firmware operative with the USB firmware library; the microprocessor being operable to: call a first communications session to configure rights of a directory and grant files access using the CCID interface and subsequently transfer mass storage data using the mass storage interface wherein only the granted files are accessible through a host application using the mass storage interface; and support a control endpoint, a bulk-in endpoint and bulk-out endpoint when communicating with a host using a mass storage interface. comprising a USB firmware library and a file system with mass storage firmware and ISO 7816 protocol and CCID protocol firmware, both the mass storage firmware and the CCID protocol firmware operative with the USB firmware library; the microprocessor being operable to: call a first communications session to configure rights of a directory and grant files access using the CCID interface and subsequently transfer mass storage data using the mass storage interface wherein only the granted files are accessible through a host application using the mass storage interface; and support a control endpoint, a bulk-in endpoint and bulk-out endpoint when communicating with a host using a mass storage interface. call a first communications session to configure rights of a directory and grant files access using the CCID interface and subsequently transfer mass storage data using the mass storage interface wherein only the granted files are accessible through a host application using the mass storage interface; and support a control endpoint, a bulk-in endpoint and bulk-out endpoint when communicating with a host using a mass storage interface.