Security for Grid Services

Grid computing is concerned with the sharing and coordinated use of diverse resources in distributed "virtual organizations." The dynamic and multi-institutional nature of these environments introduces challenging security issues that demand new technical approaches. In particular, one must deal with diverse local mechanisms, support dynamic creation of services, and enable dynamic creation of trust domains. We describe how these issues are addressed in two generations of the Globus Toolkit. First, we review the Globus Toolkit version 2 (GT2) approach; then, we describe new approaches developed to support the Globus Toolkit version 3 (GT3) implementation of the Open Grid Services Architecture, an initiative that is recasting Grid concepts within a service oriented framework based on Web services. GT3's security implementation uses Web services security mechanisms for credential exchange and other purposes, and introduces a tight least-privilege model that avoids the need for any privileged network service.Comment: 10 pages; 4 figure

Strengthening the Security of Authenticated Key Exchange against Bad Randomness

Recent history has revealed that many random number generators (RNGs) used in cryptographic algorithms and protocols were not providing appropriate randomness, either by accident or on purpose. Subsequently, researchers have proposed new algorithms and protocols that are less dependent on the random number generator. One exception is that all prominent authenticated key exchange (AKE) protocols are insecure given bad randomness, even when using good long-term keying material. We analyse the security of AKE protocols in the presence of adversaries that can perform attacks based on chosen randomness, i. e., attacks in which the adversary controls the randomness used in protocol sessions. We propose novel stateful protocols, which modify memory shared among a user’s sessions, and show in what sense they are secure against this worst case randomness failure. We develop a stronger security notion for AKE protocols that captures the security that we can achieve under such failures, and prove that our main protocol is correct in this model. Our protocols make substantially weaker assumptions on the RNG than existing protocols

SECURING CENTRALIZED SDN CONTROL WITH DISTRIBUTED BLOCKCHAIN TECHNOLOGY

Software Defined Networks (SDN) advocates segregation of network control logic, forwarding functions and management applications into different planes to achieve network programmability, automated and dynamic flow control in next generation networks. It promotes deployment of novel and augmented network management functions to have flexible, robust, scalable and cost-effective network deployments. All these features introduce new research challenges and require secure communication protocols among the segregated network planes. This manuscript focuses on the security issue of southbound interface which operates between the SDN control and data plane. We have highlighted the security threats associated with an unprotected southbound interface and the issues related with the existing TLS based security solution. A lightweight blockchain based decentralized security solution is proposed for southbound interface to secure the resources of logically centralized SDN controllers and distributed forwarding devices from opponents. The proposed mechanism can operate in multi-domain SDN deployment and can be used with wide range of network controllers and data plane devices. In addition to it, the proposed security solution is analyzed in terms of security features, communication and reauthentication overhead

ActiBot: A Botnet to Evade Active Detection

In recent years, botnets have emerged as a serious threat on the Internet. Botnets are commonly used for exploits such as distributed denial of service (DDoS) attacks, identity theft, spam, and click fraud. The immense size of botnets, some consisting of hundreds of thousands of compromised computers, increases the speed and severity of attacks. Unlike passive behavior anomaly detection techniques, active botnet detection aims to collect evidence actively, in order to reduce detection time and increase accuracy. In this project, we develop and analyze a botnet that we call ActiBot, which can evade some types of active detection mechanisms. Future research will focus on using ActiBot to strengthen existing detection techniques

Towards secure communication and authentication: Provable security analysis and new constructions

Secure communication and authentication are some of the most important and practical topics studied in modern cryptography. Plenty of cryptographic protocols have been proposed to accommodate all sorts of requirements in different settings and some of those have been widely deployed and utilized in our daily lives. It is a crucial goal to provide formal security guarantees for such protocols. In this thesis, we apply the provable security approach, a standard method used in cryptography to formally analyze the security of cryptographic protocols, to three problems related to secure communication and authentication. First, we focus on the case where a user and a server share a secret and try to authenticate each other and establish a session key for secure communication, for which we propose the first user authentication and key exchange protocols that can tolerate strong corruptions on the client-side. Next, we consider the setting where a public-key infrastructure (PKI) is available and propose models to thoroughly compare the security and availability properties of the most important low-latency secure channel establishment protocols. Finally, we perform the first provable security analysis of the new FIDO2 protocols, the promising proposed standard for passwordless user authentication from the Fast IDentity Online (FIDO) Alliance to replace the world's over-reliance on passwords to authenticate users, and design new constructions to achieve stronger security.Ph.D

Multi-ciphersuite security of the Secure Shell (SSH) protocol

The Secure Shell (SSH) protocol is widely used to provide secure remote access to servers, making it among the most important security protocols on the Internet. We show that the signed-Diffie--Hellman SSH ciphersuites of the SSH protocol are secure: each is a secure authenticated and confidential channel establishment (ACCE) protocol, the same security definition now used to describe the security of Transport Layer Security (TLS) ciphersuites. While the ACCE definition suffices to describe the security of individual ciphersuites, it does not cover the case where parties use the same long-term key with many different ciphersuites: it is common in practice for the server to use the same signing key with both finite field and elliptic curve Diffie--Hellman, for example. While TLS is vulnerable to attack in this case, we show that SSH is secure even when the same signing key is used across multiple ciphersuites. We introduce a new generic multi-ciphersuite composition framework to achieve this result in a black-box way

IoT Content Object Security with OSCORE and NDN: A First Experimental Comparison

The emerging Internet of Things (IoT) challenges the end-to-end transport of the Internet by low power lossy links and gateways that perform protocol translations. Protocols such as CoAP or MQTT-SN are degraded by the overhead of DTLS sessions, which in common deployment protect content transfer only up to the gateway. To preserve content security end-to-end via gateways and proxies, the IETF recently developed Object Security for Constrained RESTful Environments (OSCORE), which extends CoAP with content object security features commonly known from Information Centric Networks (ICN). This paper presents a comparative analysis of protocol stacks that protect request-response transactions. We measure protocol performances of CoAP over DTLS, OSCORE, and the information-centric Named Data Networking (NDN) protocol on a large-scale IoT testbed in single- and multi-hop scenarios. Our findings indicate that (a) OSCORE improves on CoAP over DTLS in error-prone wireless regimes due to omitting the overhead of maintaining security sessions at endpoints, and (b) NDN attains superior robustness and reliability due to its intrinsic network caches and hop-wise retransmissions