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Key Exchange with Anonymous Authentication Using DAA-SIGMA Protocol
Key Exchange with Anonymous Authentication using DAA-SIGMA Protocol Jesse Walker and Jiangtao Li Intel Labs {jesse.walker, jiangtao.li}@intel.com Abstract. Anonymous digital signatures such as Direct Anonymous Attestation (DAA) and group signatures have been a fundamental building block for anonymous entity authentication. In this paper, we show how to incorporate DAA schemes into a key exchange protocol between two entities to achieve anonymous authentication and to derive a shared key between them. We propose a modification to the SIGMA key exchange protocol used in the Internet Key Exchange (IKE) standards to support anonymous authentication using DAA. Our key exchange protocol can be also extended to support group signature schemes instead of DAA. We present a secure model for key exchange with anonymous authentication derived from the Canetti-Krawczyk key-exchange security model. We prove that our DAA-SIGMA protocol is secure under our security model. 1 Introduction Anonymous digital signatures such as group signatures [22, 2, 5, 6], Direct Anonymous Attestation (DAA) [7, 8, 23, 24, 14], and anonymous credentials [15–17] play an important role in privacy en- hanced technologies. They allow an entity (e.g., a user, a computer platform, or a hardware device) to create a signature without revealing its identity. Anonymous signatures also enable anonymous entity authentication. The concept of group signature scheme was first introduced by Chaum and van Heyst [22] in 1991. In a group signature scheme, all the group members share a group public key, yet each member has a unique private key. A group signature created by a group member is anonymous to all the entities except a trusted group manager. -
SGX Attestation Process Research Seminar in Cryptograpy
SGX attestation process Research seminar in Cryptograpy Author: Hiie Vill Supervisor: Pille Pullonen Introduction Software Guard Extensions (SGX) is a technology, the main function of which is to establish special protected software containers, also known as enclaves. These enclaves can be used for provisioning sensitive parts of a software executable in order to protect them from malicious entities. In order to verify remotely that an application is running securely within an enclave, a remote attestation must be performed. This report gives an overview of the attestation process, the background related to it and the necessary requirements for remote attestation [1][2]. 1. Software Guard Extensions Software Guard Extensions (SGX) is a technology introduced by Intel in 2015, which provides hardware assisted security for the application layer. In itself, SGX is a set of processor extensions for establishing a protected execution environment, referred to as an enclave, and the software related to it. More specifically, enclaves are protected areas of execution in memory, providing a trusted execution environment, even on a compromised platform. In order to protect an application from malicious entities, the software’s code, data and stack are stored within the enclave and protected by hardware enforced access control policies, making the application inaccessible to any malware on the platform. This means that SGX enables applications to defend themselves, protecting any sensitive data used by the application (for example credentials and cryptographic keys), while retaining its integrity and confidentiality [1][2]. 2. Preliminaries In this section, some terminology will be briefly explained that is used in the remote attestation process in order to familiarize the reader with the background information. -
Hannes Tschofenig
Securing IoT applications with Mbed TLS Hannes Tschofenig Part#2: Public Key-based authentication March 2018 © 2018 Arm Limited Munich Agenda • For Part #2 of the webinar we are moving from Pre-Shared Secrets (PSKs) to certificated-based authentication. • TLS-PSK ciphersuites have • great performance, • low overhead, • small code size. • Drawback is the shared key concept. • Public key cryptography was invented to deal with this drawback (but itself has drawbacks). 2 © 2018 Arm Limited Public Key Infrastructure and certificate configuration © 2018 Arm Limited Public Key Infrastructure Various PKI deployments in existence Structure of our PKI The client has to store: self-signed • Client certificate plus corresponding private key. CA cert • CA certificate, which serves as the trust anchor. The server has to store: Signed by CA Signed by CA • Server certificate plus corresponding private key. Client cert Server cert (Some information for authenticating the client) 4 © 2018 Arm Limited Generating certificates (using OpenSSL tools) • When generating certificates you will be prompted to enter info. You are about to be asked to enter information that will be • The CA cert will end up in the trust incorporated into your certificate request. What you are about to enter is what is called a Distinguished anchor store of the client. Name or a DN. There are quite a few fields but you can leave some blank For some fields there will be a default value, • The Common Name used in the server If you enter '.', the field will be left blank. ----- cert needs to be resolvable via DNS Country Name (2 letter code) [AU]:. -
Arxiv:1911.09312V2 [Cs.CR] 12 Dec 2019
Revisiting and Evaluating Software Side-channel Vulnerabilities and Countermeasures in Cryptographic Applications Tianwei Zhang Jun Jiang Yinqian Zhang Nanyang Technological University Two Sigma Investments, LP The Ohio State University [email protected] [email protected] [email protected] Abstract—We systematize software side-channel attacks with three questions: (1) What are the common and distinct a focus on vulnerabilities and countermeasures in the cryp- features of various vulnerabilities? (2) What are common tographic implementations. Particularly, we survey past re- mitigation strategies? (3) What is the status quo of cryp- search literature to categorize vulnerable implementations, tographic applications regarding side-channel vulnerabili- and identify common strategies to eliminate them. We then ties? Past work only surveyed attack techniques and media evaluate popular libraries and applications, quantitatively [20–31], without offering unified summaries for software measuring and comparing the vulnerability severity, re- vulnerabilities and countermeasures that are more useful. sponse time and coverage. Based on these characterizations This paper provides a comprehensive characterization and evaluations, we offer some insights for side-channel of side-channel vulnerabilities and countermeasures, as researchers, cryptographic software developers and users. well as evaluations of cryptographic applications related We hope our study can inspire the side-channel research to side-channel attacks. We present this study in three di- community to discover new vulnerabilities, and more im- rections. (1) Systematization of literature: we characterize portantly, to fortify applications against them. the vulnerabilities from past work with regard to the im- plementations; for each vulnerability, we describe the root cause and the technique required to launch a successful 1. -
Black-Box Security Analysis of State Machine Implementations Joeri De Ruiter
Black-box security analysis of state machine implementations Joeri de Ruiter 18-03-2019 Agenda 1. Why are state machines interesting? 2. How do we know that the state machine is implemented correctly? 3. What can go wrong if the implementation is incorrect? What are state machines? • Almost every protocol includes some kind of state • State machine is a model of the different states and the transitions between them • When receiving a messages, given the current state: • Decide what action to perform • Which message to respond with • Which state to go the next Why are state machines interesting? • State machines play a very important role in security protocols • For example: • Is the user authenticated? • Did we agree on keys? And if so, which keys? • Are we encrypting our traffic? • Every implementation of a protocol has to include the corresponding state machine • Mistakes can lead to serious security issues! State machine example Confirm transaction Verify PIN 0000 Failed Init Failed Verify PIN 1234 OK Verified Confirm transaction OK State machines in specifications • Often specifications do not explicitly contain a state machine • Mainly explained in lots of prose • Focus usually on happy flow • What to do if protocol flow deviates from this? Client Server ClientHello --------> ServerHello Certificate* ServerKeyExchange* CertificateRequest* <-------- ServerHelloDone Certificate* ClientKeyExchange CertificateVerify* [ChangeCipherSpec] Finished --------> [ChangeCipherSpec] <-------- Finished Application Data <-------> Application Data -
Demystifying Internet of Things Security Successful Iot Device/Edge and Platform Security Deployment — Sunil Cheruvu Anil Kumar Ned Smith David M
Demystifying Internet of Things Security Successful IoT Device/Edge and Platform Security Deployment — Sunil Cheruvu Anil Kumar Ned Smith David M. Wheeler Demystifying Internet of Things Security Successful IoT Device/Edge and Platform Security Deployment Sunil Cheruvu Anil Kumar Ned Smith David M. Wheeler Demystifying Internet of Things Security: Successful IoT Device/Edge and Platform Security Deployment Sunil Cheruvu Anil Kumar Chandler, AZ, USA Chandler, AZ, USA Ned Smith David M. Wheeler Beaverton, OR, USA Gilbert, AZ, USA ISBN-13 (pbk): 978-1-4842-2895-1 ISBN-13 (electronic): 978-1-4842-2896-8 https://doi.org/10.1007/978-1-4842-2896-8 Copyright © 2020 by The Editor(s) (if applicable) and The Author(s) This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Open Access This book is licensed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made. The images or other third party material in this book are included in the book’s Creative Commons license, unless indicated otherwise in a credit line to the material. -
7) Internet of Things a Survey on the Security of Iot Frameworks
Journal of Information Security and Applications 38 (2018) 8–27 Contents lists available at ScienceDirect Journal of Information Security and Applications journal homepage: www.elsevier.com/locate/jisa Internet of Things: A survey on the security of IoT frameworks ∗ Mahmoud Ammar a, , Giovanni Russello b, Bruno Crispo a a Department of Computer Science, KU Leuven University, Heverlee, 3001, Belgium b Department of Computer Science, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand a r t i c l e i n f o a b s t r a c t Article history: The Internet of Things (IoT) is heavily affecting our daily lives in many domains, ranging from tiny wear- able devices to large industrial systems. Consequently, a wide variety of IoT applications have been devel- Keywords: oped and deployed using different IoT frameworks. An IoT framework is a set of guiding rules, protocols, Internet of Things and standards which simplify the implementation of IoT applications. The success of these applications IoT mainly depends on the ecosystem characteristics of the IoT framework, with the emphasis on the security Framework mechanisms employed in it, where issues related to security and privacy are pivotal. In this paper, we sur- Platform vey the security of the main IoT frameworks, a total of 8 frameworks are considered. For each framework, Security we clarify the proposed architecture, the essentials of developing third-party smart apps, the compati- ble hardware, and the security features. Comparing security architectures shows that the same standards used for securing communications, whereas different methodologies followed for providing other security properties. -
Performance of State-Of-The-Art Cryptography on ARM-Based Microprocessors
NIST Lightweight Cryptography Workshop 2015 Session VII: Implementations & Performance Performance of State-of-the-Art Cryptography on ARM-based Microprocessors Hannes Tschofenig & Manuel Pegourie-Gonnard ([email protected], [email protected] ) Presented by Hugo Vincent ([email protected] ) IoT Business Unit Tuesday, July 21, 2015 1 Outline § Why does ARM care about crypto performance? § ARM Cortex-M vs. Cortex-A Class processors. § Short overview of the Cortex-M processor family. § Internet of Things – a world full of constraints. § Performance of crypto on Cortex-M class processors § Assumptions § Hardware used for measurement § Symmetric Key Cryptography § Public Key Crypto (with different curves) § Cortex-M3/M4 Performance § Cortex-M0/M0+ Performance § Curve25519 § RAM Usage § Applying Results to TLS/DTLS § Conclusion & Next Steps 2 Why does ARM care about Crypto Performance? 3 ARM Processors in Smartphones § ARM Cortex-A family: § Applications processors for feature-rich OS and 3rd party applications § ARM Cortex-R family: § Embedded processors for real-time signal processing, control applications § ARM Cortex-M family: § Microcontroller- oriented processors for MCU, ASSP, and SoC applications 4 Cortex-M Processors Maximum Performance Flexible Memory Cache Single & Double Precision FP Digital Signal Control (DSC)/ Examples: Automotive, Processor with DSP High-end audio set Accelerated SIMD Performance & efficiency Floating point (FP) Example: Sensor fusion, Feature rich connectivity motor control Example: -
Easy Encryption for Email, Photo, and Other Cloud Services John Seunghyun Koh
Easy Encryption for Email, Photo, and Other Cloud Services John Seunghyun Koh Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy under the Executive Committee of the Graduate School of Arts and Sciences COLUMBIA UNIVERSITY 2021 © 2021 John Seunghyun Koh All Rights Reserved Abstract Easy Encryption for Email, Photo, and Other Cloud Services John Seunghyun Koh Modern users carry mobile devices with them at nearly all times, and this likely has contribut- ed to the rapid growth of private user data—such as emails, photos, and more—stored online in the cloud. Unfortunately, the security of many cloud services for user data is lacking, and the vast amount of user data stored in the cloud is an attractive target for adversaries. Even a single compro- mise of a user’s account yields all its data to attackers. A breach of an unencrypted email account gives the attacker full access to years, even decades, of emails. Ideally, users would encrypt their data to prevent this. However, encrypting data at rest has long been considered too difficult for users, even technical ones, mainly due to the confusing nature of managing cryptographic keys. My thesis is that strong security can be made easy to use through client-side encryption using self-generated per-device cryptographic keys, such that user data in cloud services is well pro- tected, encryption is transparent and largely unnoticeable to users even on multiple devices, and encryption can be used with existing services without any server-side modifications. This dis- sertation introduces a new paradigm for usable cryptographic key management, Per-Device Keys (PDK), and explores how self-generated keys unique to every device can enable new client-side encryption schemes that are compatible with existing online services yet are transparent to users. -
Downloads BC Cessful, Then L Proceeds with Querying S for Available 8: SU (I) Run REKEYING( (I)) in Next DB SU (I) S ∈C C Tepoch Channels
TrustSAS: A Trustworthy Spectrum Access System for the 3.5 GHz CBRS Band Mohamed Grissa⋆, Attila A. Yavuz‡, and Bechir Hamdaoui⋆ ⋆ Oregon State University, grissam,[email protected] ‡ University of South Florida, [email protected] Abstract—As part of its ongoing efforts to meet the increased PU s. GAA users, on the other hand, operate opportunistically, spectrum demand, the Federal Communications Commission in that they need to query the DBs to learn about which 150 3.5 (FCC) has recently opened up MHz in the GHz band spectrum portions are available—not being used by higher tier for shared wireless broadband use. Access and operations in this PU band, aka Citizens Broadband Radio Service (CBRS), will be ( or PAL) users. Even though both PAL and GAA users managed by a dynamic spectrum access system (SAS) to enable are considered as secondary users, in the remaining parts of seamless spectrum sharing between secondary users (SU s) and this paper, for ease of illustration, SU refers to a GAA user, incumbent users. Despite its benefits, SAS ’s design requirements, since only GAA users need to query DBs to learn spectrum SU as set by FCC, present privacy risks to s, merely because availability; PAL users acquire spectrum access via bidding. SU s are required to share sensitive operational information (e.g., location, identity, spectrum usage) with SAS to be able A. Key SAS Requirements to learn about spectrum availability in their vicinity. In this As stipulated by FCC [1], SAS’s capabilities will exceed paper, we propose TrustSAS , a trustworthy framework for SAS that synergizes state-of-the-art cryptographic techniques those of TVWS [4], allowing a more dynamic, responsive with blockchain technology in an innovative way to address these and generally capable support of a diverse set of operational privacy issues while complying with FCC’s regulatory design scenarios and heterogeneous networks [5]. -
Performance Investigations
Performance Investigations Hannes Tschofenig, Manuel Pégourié-Gonnard 25th March 2015 1 Motivation § In <draft-ietf-lwig-tls-minimal> we tried to provide guidance for the use of DTLS (TLS) when used in IoT deployments and included performance data to help understand the design tradeoffs. § Later, work in the IETF DICE was started with the profile draft, which offers detailed guidance concerning credential types, communication patterns. It also indicates which extensions to use or not to use. § Goal of <draft-ietf-lwig-tls-minimal> is to offer performance data based on the recommendations in the profile draft. § This presentation is about the current status of gathering performance data for later inclusion into the <draft-ietf-lwig-tls-minimal> document. 2 Performance Data § This is the data we want: § Flash code size § Message size / Communication Overhead § CPU performance § Energy consumption § RAM usage § Also allows us to judge the improvements of various extensions and gives engineers a rough idea what to expect when planning to use DTLS/TLS in an IoT product. § <draft-ietf-lwig-tls-minimal-01> offers preliminary data about § Code size of various basic building blocks (data from one stack only) § Memory (RAM/flash) (pre-shared secret credential only) § Communication overhead (high level only) 3 Overview § Goal of the authors: Determine performance of asymmetric cryptography on ARM-based processors. § Next slides explains § Assumptions for the measurements, § ARM processors used for the measurements, § Development boards used, § Actual performance data, and § Comparison with other algorithms. 4 Assumptions § Main focus of the measurements so far was on § raw crypto (and not on protocol exchanges) § ECC rather than RSA § Different ECC curves § Run-time performance (not energy consumption, RAM usage, code size) § No hardware acceleration was used. -
Best Practices for Privileged Access Management on Cloud-Native Infrastructure
Best Practices for Privileged Access Management on Cloud-Native Infrastructure BY GRAVITATIONAL CONTENTS INTRODUCTION ......................................................................................................................................................................... 4 BACKGROUND OF ACCESS MANAGEMENT COMPONENTS ...................................................................................... 5 SSH ............................................................................................................................................................................................. 5 SSH Public Key Authentication ............................................................................................................................................ 5 OpenSSH Certificates ............................................................................................................................................................. 7 OpenSSH Certificate Authentication .................................................................................................................................. 7 LDAP .......................................................................................................................................................................................... 8 Identity Provider ...................................................................................................................................................................... 9 AUTHENTICATION AND AUTHORIZATION ...................................................................................................................