GlobalPlatform

Java Card Tutorial: Implementing Supplementary Security Domain to Limit ISD Privileges

A detailed technical guide demonstrates how to create a Supplementary Security Domain (SSD) on Java Card platforms to isolate applet management from the Issuer Security Domain (ISD). The approach prevents full card compromise if ISD keys are exposed by restricting SSD privileges to specific functions such as accepting extradition only from the ISD. Using the FunGP library and SCP02 protocol, the tutorial walks through installation, personalization with encrypted keys, and extradition of applets under the new domain. GlobalPlatform specifications including GP CS v2.3 and GP CIC v2.0 are followed for install parameters, privileges, and STORE DATA commands. After personalization the SSD reaches the PERSONALIZED lifecycle state, allowing secure delegation of applet control while the ISD retains overall card management rights. The method eliminates the need for custom operating systems and provides a standards-compliant way to enforce least-privilege access on smart cards.

Secure Personalization of Java Card Applets Using Issuer Security Domain and SCP02

The article explains how to leverage the Issuer Security Domain mechanisms on GlobalPlatform cards to establish secure channels for applet personalization without implementing custom ECDH-based key exchange. It addresses limitations of prior approaches that lacked authentication and required extensive PKI support. The solution uses SCP02 with specific security levels such as C_MAC and C_DECRYPTION to protect commands that store AES-128 keys and personal data on the card. Detailed code walkthroughs cover the applet constructor, process method, mutual authentication via SecureChannel.processSecurity, and unwrap operations for decrypting and verifying APDUs. Practical testing on NXP Java Cards demonstrates installation via FunGP library scripts that allow configurable security levels during mutual authentication. The implementation ensures that secret key updates enforce C_DECRYPTION while personal data writes accept C_MAC, with encrypted reads performed using AES-CBC.