Cryptanalysis of GlobalPlatform Secure Channel Protocols

GlobalPlatform (GP) card specifications are the de facto standards for the industry of smart cards. Being highly sensitive, GP specifications were defined regarding stringent security requirements. In this paper, we analyze the cryptographic core of these requirements; i.e. the family of Secure Channel Protocols (SCP). Our main results are twofold. First, we demonstrate a theoretical attack against SCP02, which is the most popular protocol in the SCP family. We discuss the scope of our attack by presenting an actual scenario in which a malicious entity can exploit it in order to recover encrypted messages. Second, we investigate the security of SCP03 that was introduced as an amendment in 2009. We find that it provably satisfies strong notions of security. Of particular interest, we prove that SCP03 withstands algorithm substitution attacks (ASAs) defined by Bellare et al. that may lead to secret mass surveillance. Our findings highlight the great value of the paradigm of provable security for standards and certification, since unlike extensive evaluation, it formally guarantees the absence of security flaws

Supporting NAT traversal and secure communications in a protocol implementation framework

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do Grau de Mestre em Engenharia Electrotécnica e de ComputadoresThe DOORS framework is a versatile, lightweight message-based framework developed in ANSI C++. It builds upon research experience and subsequent knowledge garnered from the use and development of CVOPS and OVOPS, two well known protocol development frameworks that have obtained widespread acceptance and use in both the Finnish industry and academia. It conceptually resides between the operating system and the application, and provides a uniform development environment shielding the developer from operating system speci c issues. It can be used for developing network services, ranging from simple socket-based systems, to protocol implementations, to CORBA-based applications and object-based gateways. Originally, DOORS was conceived as a natural extension from the OVOPS framework to support generic event-based, distributed and client-server network applications. However, DOORS since then has evolved as a platform-level middleware solution for researching the provision of converged services to both packet-based and telecommunications networks, enterprise-level integration and interoperability in future networks, as well as studying application development, multi-casting and service discovery protocols in heterogeneous IPv6 networks. In this thesis, two aspects of development work with DOORS take place. The rst is the investigation of the Network Address Translation (NAT) traversal problem to give support to applications in the DOORS framework that are residing in private IP networks to interwork with those in public IP networks. For this matter this rst part focuses on the development of a client in the DOORS framework for the Session Traversal Utilities for NAT (STUN) protocol, to be used for IP communications behind a NAT. The second aspect involves secure communications. Application protocols in communication networks are easily intercepted and need security in various layers. For this matter the second part focuses on the investigation and development of a technique in the DOORS framework to support the Transport Layer Security (TLS) protocol, giving the ability to application protocols to rely on secure transport layer services

New Classes of Binary Random Sequences for Cryptography

In the vision for the 5G wireless communications advancement that yield new security prerequisites and challenges we propose a catalog of three new classes of pseudorandom random sequence generators. This dissertation starts with a review on the requirements of 5G wireless networking systems and the most recent development of the wireless security services applied to 5G, such as private-keys generation, key protection, and flexible authentication. This dissertation proposes new complexity theory-based, number-theoretic approaches to generate lightweight pseudorandom sequences, which protect the private information using spread spectrum techniques. For the class of new pseudorandom sequences, we obtain the generalization. Authentication issues of communicating parties in the basic model of Piggy Bank cryptography is considered and a flexible authentication using a certified authority is proposed