A User Centric Security Model for Tamper-Resistant Devices

6.3 Secure and Trusted Channel Protocol Service Provider
PrA-3 Secure Cryptographic Algorithms: The cryptographic algorithms used in the protocol
that include symmetric, asymmetric, and signature algorithms are secure against
a computationally bound adversary.
6.3 Secure and Trusted Channel Protocol Service Provider
In this section, we begin the discussion with a description of the proposed STCP SP along
with the rejection messages.
6.3.1 Protocol Prerequisites
The prerequisites to the STCP SP are listed below. This is an extension to the prerequisite
list in section 4.7.1.
PPR-8 User Signature Key Pair: When a user has taken ownership of a smart card and on
the successful conclusion of this process, the smart card generates a user signature
key pair. This key pair is used to provide proof of ownership during the STCP SP .
PPR-9 Authorised Customer: The user is a registered customer of the SP, which means
that the SP has sanctioned the user to download (lease) their application.
PPR-10 Established Connection: The user has the knowledge of the respective SP's application
server (AMS: gure 3.6) that the SP has provided to the smart card. The
smart card in return connects with the SP. Furthermore, the SP has knowledge of
the smart card's Internet Protocol (IP) address.
6.3.2 Protocol Description
In this protocol, the SP takes the role of the protocol initiator. The design of this STCP
variant is inspired by the requirements of user authentication as discussed in section 5.4.4.
STCP SP -1. SP : SI = f kSP (g r SP
||N SP ||SC IP )
SP → SC : SP i ||V R||N SP ||g r SP
||SP Sup ||SP Sel ||SI
SC : K = (g r SP
) r SC
mod p
SC : ek SC−SP = H K (N SP ||N SC || ′ 1 ′ )
SC : mk SC−SP = H K (N SP ||N SC || ′ 2 ′ )
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