CryptoVerif Tutorial


 Amanda Chambers
 3 years ago
 Views:
Transcription
1 CryptoVerif Tutorial Bruno Blanchet INRIA ParisRocquencourt November 2014 Bruno Blanchet (INRIA) CryptoVerif Tutorial November / 14
2 Exercise 1: preliminary definition SUFCMA Definition (SUFCMA MACs) The advantage of the adversary against strong unforgeability under chosen message attacks (SUFCMA) of MACs is: Succ suf cma MAC (t, q m, q v, l) = [ max Pr A k R mkgen; (m, s) A mac(.,k),verify(.,k,.) : verify(m, k, s) s is not the result of calling the oracle mac(., k) on m where A runs in time at most t, calls mac(., k) at most q m times with messages of length at most l, calls verify(., k,.) at most q v times with messages of length at most l. MAC is SUFCMA if and only if Succ suf cma MAC (t, q m, q v, l) is negligible when t, q m, q v, l are polynomial in the security parameter. ] Bruno Blanchet (INRIA) CryptoVerif Tutorial November / 14
3 Exercise 1: preliminary definition INDCCA2 Definition (INDCCA2 symmetric encryption) The advantage of the adversary against indistinguishabibility under adaptive chosenciphertext attacks (INDCCA2) of a symmetric encryption scheme SE is: Succ ind cca2 SE (t, q e, q d, l e, l d ) = b {0, R 1}; k R kgen; max 2 Pr b A enc(lr(.,.,b),k),dec(.,k) : b = b A A has not called dec(., k) on the result of 1 enc(lr(.,., b), k) where A runs in time at most t, calls enc(lr(.,., b), k) at most q e times on messages of length at most l e, calls dec(., k) at most q d times on messages of length at most l d. SE is INDCCA2 if and only if Succ ind cca2 SE (t, q e, q d, l e, l d ) is negligible when t, q e, q d, L e, l d are polynomial in the security parameter. Bruno Blanchet (INRIA) CryptoVerif Tutorial November / 14
4 Exercise 1: preliminary definition INTCTXT Definition (INTCTXT symmetric encryption) The advantage of the adversary against ciphertext integrity (INTCTXT) of a symmetric encryption scheme SE is: Succ int ctxt SE (t, q e, q d, l e, l d ) = [ max Pr A k R kgen; c A enc(.,k),dec(.,k) : dec(c, k) c is not the result of a call to the enc(., k) oracle where A runs in time at most t, calls enc(., k) at most q e times with messages of length at most l e, calls dec(., k) at most q d times with messages of length at most l d. SE is INTCTXT if and only if Succ int ctxt SE (t, q e, q d, l e, l d ) is negligible when t, q e, q d, L e, l d are polynomial in the security parameter. ] Bruno Blanchet (INRIA) CryptoVerif Tutorial November / 14
5 Exercise 1 1 Show using CryptoVerif that, if the MAC scheme is SUFCMA and the encryption scheme is INDCPA, then the encryptthenmac scheme is INDCPA. 2 Show using the same assumptions that the encryptthenmac scheme is INDCCA2. 3 Show using the same assumptions that the encryptthenmac scheme is INTCTXT. 4 What happens if the MAC scheme is only UFCMA? Bruno Blanchet (INRIA) CryptoVerif Tutorial November / 14
6 Exercise 2: Preliminary definition A publickey encryption scheme AE consists of a key generation algorithm (pk, sk) R kgen a probabilistic encryption algorithm enc(m, pk) a decryption algorithm dec(m, sk) such that dec(enc(m, pk), sk) = m. The advantage of the adversary against indistinguishability under chosenplaintext attacks (INDCPA) is Succ ind cca2 AE (t) = max 2 Pr b {0, R 1}; (pk, sk) R kgen; (m A 0, m 1, s) A 1 (pk); y enc(m b, pk); 1 b A 2 (m 0, m 1, s, y) : b = b where A = (A 1, A 2 ) runs in time at most t. AE is INDCPA if and only if Succ ind cpa AE (t) is negligible when t is polynomial in the security parameter. Bruno Blanchet (INRIA) CryptoVerif Tutorial November / 14
7 Exercise 2 Suppose that H is a hash function in the Random Oracle Model and that f is a oneway trapdoor permutation. Consider the encryption function E pk (x) = f pk (r) H(r) x, where denotes concatenation and denotes exclusive or (Bellare & Rogaway, CCS 93). What is the decryption function? Show using CryptoVerif that this publickey encryption scheme is INDCPA. Bruno Blanchet (INRIA) CryptoVerif Tutorial November / 14
8 Exercise 3 Consider the fixed version of the WooLam sharedkey protocol, by Gordon and Jeffrey (CSFW 01): A B: B A: A B: B S: S B: A N (fresh nonce) {m3, B, N} kas A, B, {m3, B, N} kas {m5, A, N} kbs At the end, B verifies that {m5, A, N} kbs is the message from S. Show that, at the end of the protocol, A is authenticated to B. Suggestion: one may consider 1 First, a simple version in which A talks only to B, B talks only to A, and S talks only to A and B. 2 Then, generalize to the case in which A, B, and S may also talk to dishonest participants. Bruno Blanchet (INRIA) CryptoVerif Tutorial November / 14
9 Exercise 4 Consider the NeedhamSchroeder publickey protocol, as fixed by Lowe. We first consider a simplified version without certificates: A B: B A: A B: {N A, pk A } pkb {N A, N B, pk B } pka {N B } pkb Show that, at the end of the protocol, A and B are mutually authenticated. Bruno Blanchet (INRIA) CryptoVerif Tutorial November / 14
10 Exercise 4 Now consider the full version with certificates: A S: (A, B) S A: (pk B, B, {pk B, B} sks ) A B: {N A, A} pkb B S: (B, A) S B: (pk A, A, {pk A, A} sks ) B A: {N A, N B, B} pka A B: {N B } pkb Show that, at the end of the protocol, A and B are mutually authenticated. Bruno Blanchet (INRIA) CryptoVerif Tutorial November / 14
11 Exercise 5 The advantage of the adversary against strong unforgeability under chosen message attacks (SUFCMA) of MACs is: Succ suf cma MAC (t, q m, q v, l) = [ max Pr A k R mkgen; (m, s) A mac(.,k),verify(.,k,.) : verify(m, k, s) s is not the result of calling the oracle mac(., k) on m where A runs in time at most t, calls mac(., k) at most q m times with messages of length at most l, calls verify(., k,.) at most q v times with messages of length at most l. Represent SUFCMA MACs in the CryptoVerif formalism. ] Bruno Blanchet (INRIA) CryptoVerif Tutorial November / 14
12 Exercise 6 A signature scheme S consists of a key generation algorithm (pk, sk) R kgen a signature algorithm sign(m, sk) a verification algorithm verify(m, pk, s) such that verify(m, pk, sign(m, sk)) = 1. The advantage of the adversary against unforgeability under chosen message attacks (UFCMA) of signatures is: Succ uf cma S (t, q s, l) = [ max Pr A (pk, sk) R kgen; (m, s) A sign(.,sk) (pk) : verify(m, pk, s) m was never queried to the oracle sign(., sk) where A runs in time at most t, calls sign(., sk) at most q s times with messages of length at most l. Represent UFCMA signatures in the CryptoVerif formalism. Bruno Blanchet (INRIA) CryptoVerif Tutorial November / 14 ]
13 Exercise 7 The advantage of the adversary against ciphertext integrity (INTCTXT) of a symmetric encryption scheme SE is: Succ int ctxt SE (t, q e, q d, l e, l d ) = [ max Pr A k R kgen; c A enc(.,k),dec(.,k) : dec(c, k) c is not the result of a call to the enc(., k) oracle where A runs in time at most t, calls enc(., k) at most q e times with messages of length at most l e, calls dec(., k) at most q d times with messages of length at most l d. Represent INTCTXT encryption in the CryptoVerif formalism. ] Bruno Blanchet (INRIA) CryptoVerif Tutorial November / 14
14 Exercise 8 A publickey encryption scheme AE consists of a key generation algorithm (pk, sk) R kgen a probabilistic encryption algorithm enc(m, pk) a decryption algorithm dec(m, sk) such that dec(enc(m, pk), sk) = m. The advantage of the adversary against indistinguishability under adaptive chosenciphertext attacks (INDCCA2) is Succ ind cca2 AE (t, q d ) = b {0, R 1}; (pk, sk) R kgen; max 2 Pr (m 0, m 1, s) A dec(.,sk) 1 (pk); y enc(m b, pk); A b A dec(.,sk) 2 (m 0, m 1, s, y) : b = b 1 A 2 has not called dec(., sk) on y where A = (A 1, A 2 ) runs in time at most t and calls dec(., sk) at most q d times. Represent INDCCA2 encryption in the CryptoVerif formalism. Bruno Blanchet (INRIA) CryptoVerif Tutorial November / 14
Authenticated Encryption: Relations among Notions and Analysis of the Generic Composition Paradigm By Mihir Bellare and Chanathip Namprempre
Authenticated Encryption: Relations among Notions and Analysis of the Generic Composition Paradigm By Mihir Bellare and Chanathip Namprempre Some slides were also taken from Chanathip Namprempre's defense
More informationProvableSecurity Analysis of Authenticated Encryption in Kerberos
ProvableSecurity Analysis of Authenticated Encryption in Kerberos Alexandra Boldyreva Virendra Kumar Georgia Institute of Technology, School of Computer Science 266 Ferst Drive, Atlanta, GA 303320765
More informationCiphertext verification security of symmetric encryption schemes
www.scichina.com info.scichina.com www.springerlink.com Ciphertext verification security of symmetric encryption schemes HU ZhenYu 1, SUN FuChun 1 & JIANG JianChun 2 1 National Laboratory of Information
More informationAuthenticated Encryption: Relations among notions and analysis of the generic composition paradigm
An extended abstract of this paper appears in Tatsuaki Okamoto, editor, Advances in Cryptology ASIACRYPT 2000, Volume 1976 of Lecture Notes in Computer Science, pages 531 545, Kyoto, Japan, December 3
More informationIntroduction. Chapter 1
Chapter 1 Introduction This is a chapter from version 1.1 of the book Mathematics of Public Key Cryptography by Steven Galbraith, available from http://www.isg.rhul.ac.uk/ sdg/cryptobook/ The copyright
More informationIntroduction. Digital Signature
Introduction Electronic transactions and activities taken place over Internet need to be protected against all kinds of interference, accidental or malicious. The general task of the information technology
More informationAuthenticated Encryption (AE) Instructor: Ahmad Boorghany
Sharif University of Technology Department of Computer Engineering Data and Network Security Lab Authenticated Encryption (AE) Instructor: Ahmad Boorghany Most of the slides are obtained from Bellare and
More informationMESSAGE AUTHENTICATION IN AN IDENTITYBASED ENCRYPTION SCHEME: 1KEYENCRYPTTHENMAC
MESSAGE AUTHENTICATION IN AN IDENTITYBASED ENCRYPTION SCHEME: 1KEYENCRYPTTHENMAC by Brittanney Jaclyn Amento A Thesis Submitted to the Faculty of The Charles E. Schmidt College of Science in Partial
More informationLecture 3: OneWay Encryption, RSA Example
ICS 180: Introduction to Cryptography April 13, 2004 Lecturer: Stanislaw Jarecki Lecture 3: OneWay Encryption, RSA Example 1 LECTURE SUMMARY We look at a different security property one might require
More informationThe Order of Encryption and Authentication for Protecting Communications (Or: How Secure is SSL?)
The Order of Encryption and Authentication for Protecting Communications (Or: How Secure is SSL?) Hugo Krawczyk Abstract. We study the question of how to generically compose symmetric encryption and authentication
More information1 Message Authentication
Theoretical Foundations of Cryptography Lecture Georgia Tech, Spring 200 Message Authentication Message Authentication Instructor: Chris Peikert Scribe: Daniel Dadush We start with some simple questions
More informationDIGITAL SIGNATURES 1/1
DIGITAL SIGNATURES 1/1 Signing by hand COSMO ALICE ALICE Pay Bob $100 Cosmo Alice Alice Bank =? no Don t yes pay Bob 2/1 Signing electronically Bank Internet SIGFILE } {{ } 101 1 ALICE Pay Bob $100 scan
More informationReconsidering Generic Composition
Reconsidering Generic Composition Chanathip Namprempre Thammasat University, Thailand Phillip Rogaway University of California, Davis, USA Tom Shrimpton Portland State University, USA 1/24 What is the
More informationAuthentication and Encryption: How to order them? Motivation
Authentication and Encryption: How to order them? Debdeep Muhopadhyay IIT Kharagpur Motivation Wide spread use of internet requires establishment of a secure channel. Typical implementations operate in
More informationMACs Message authentication and integrity. Table of contents
MACs Message authentication and integrity Foundations of Cryptography Computer Science Department Wellesley College Table of contents Introduction MACs Constructing Secure MACs Secure communication and
More information1 Construction of CCAsecure encryption
CSCI 5440: Cryptography Lecture 5 The Chinese University of Hong Kong 10 October 2012 1 Construction of secure encryption We now show how the MAC can be applied to obtain a secure encryption scheme.
More informationChapter 11. Asymmetric Encryption. 11.1 Asymmetric encryption schemes
Chapter 11 Asymmetric Encryption The setting of publickey cryptography is also called the asymmetric setting due to the asymmetry in key information held by the parties. Namely one party has a secret
More informationSemantic Security for the McEliece Cryptosystem without Random Oracles
Semantic Security for the McEliece Cryptosystem without Random Oracles Ryo Nojima 1, Hideki Imai 23, Kazukuni Kobara 3, and Kirill Morozov 3 1 National Institute of Information and Communications Technology
More informationCS155. Cryptography Overview
CS155 Cryptography Overview Cryptography Is n A tremendous tool n The basis for many security mechanisms Is not n The solution to all security problems n Reliable unless implemented properly n Reliable
More informationKEY DISTRIBUTION: PKI and SESSIONKEY EXCHANGE. Mihir Bellare UCSD 1
KEY DISTRIBUTION: PKI and SESSIONKEY EXCHANGE Mihir Bellare UCSD 1 The public key setting Alice M D sk[a] (C) Bob pk[a] C C $ E pk[a] (M) σ $ S sk[a] (M) M, σ Vpk[A] (M, σ) Bob can: send encrypted data
More informationPrivacy in Encrypted Content Distribution Using Private Broadcast Encryption
Privacy in Encrypted Content Distribution Using Private Broadcast Encryption Adam Barth 1, Dan Boneh 1, and Brent Waters 2 1 Stanford University, Stanford, CA 94305 {abarth, dabo}@cs.stanford.edu 2 SRI
More informationRSA OAEP is Secure under the RSA Assumption
This is a revised version of the extended abstract RSA OAEP is Secure under the RSA Assumption which appeared in Advances in Cryptology Proceedings of CRYPTO 2001 (19 23 august 2001, Santa Barbara, California,
More information1 Digital Signatures. 1.1 The RSA Function: The eth Power Map on Z n. Crypto: Primitives and Protocols Lecture 6.
1 Digital Signatures A digital signature is a fundamental cryptographic primitive, technologically equivalent to a handwritten signature. In many applications, digital signatures are used as building blocks
More informationFoundations of Group Signatures: The Case of Dynamic Groups
A preliminary version of this paper appears in Topics in Cryptology CTRSA 05, Lecture Notes in Computer Science Vol.??, A. Menezes ed., SpringerVerlag, 2005. This is the full version. Foundations of
More informationMultiRecipient Encryption Schemes: Efficient Constructions and their Security
This is the full version of the paper with same title that appeared in IEEE Transactions on Information Theory, Volume 53, Number 11, 2007. It extends the previously published versions Ku, BBS. MultiRecipient
More informationSimple and Efficient PublicKey Encryption from Computational DiffieHellman in the Standard Model
Simple and Efficient PublicKey Encryption from Computational DiffieHellman in the Standard Model Kristiyan Haralambiev 1 Tibor Jager 2 Eike Kiltz 3 Victor Shoup 4 Abstract This paper proposes practical
More informationChosenCiphertext Security from IdentityBased Encryption
ChosenCiphertext Security from IdentityBased Encryption Dan Boneh Ran Canetti Shai Halevi Jonathan Katz Abstract We propose simple and efficient CCAsecure publickey encryption schemes (i.e., schemes
More informationAuthenticated encryption
Authenticated encryption Dr. Enigma Department of Electrical Engineering & Computer Science University of Central Florida wocjan@eecs.ucf.edu October 16th, 2013 Active attacks on CPAsecure encryption
More informationMAC. SKE in Practice. Lecture 5
MAC. SKE in Practice. Lecture 5 Active Adversary Active Adversary An active adversary can inject messages into the channel Active Adversary An active adversary can inject messages into the channel Eve
More informationChapter 12. Digital signatures. 12.1 Digital signature schemes
Chapter 12 Digital signatures In the public key setting, the primitive used to provide data integrity is a digital signature scheme. In this chapter we look at security notions and constructions for this
More informationCryptoVerifying Protocol Implementations in ML
CryptoVerifying Protocol Implementations in ML Karthikeyan Bhargavan 1,2 Ricardo Corin 1,3 Cédric Fournet 1,2 1 MSRINRIA Joint Centre 2 Microsoft Research 3 University of Twente June 2007 Abstract We
More informationOutline. Computer Science 418. Digital Signatures: Observations. Digital Signatures: Definition. Definition 1 (Digital signature) Digital Signatures
Outline Computer Science 418 Digital Signatures Mike Jacobson Department of Computer Science University of Calgary Week 12 1 Digital Signatures 2 Signatures via Public Key Cryptosystems 3 Provable 4 Mike
More information1 Signatures vs. MACs
CS 120/ E177: Introduction to Cryptography Salil Vadhan and Alon Rosen Nov. 22, 2006 Lecture Notes 17: Digital Signatures Recommended Reading. KatzLindell 10 1 Signatures vs. MACs Digital signatures
More informationLecture 10: CPA Encryption, MACs, Hash Functions. 2 Recap of last lecture  PRGs for one time pads
CS 7880 Graduate Cryptography October 15, 2015 Lecture 10: CPA Encryption, MACs, Hash Functions Lecturer: Daniel Wichs Scribe: Matthew Dippel 1 Topic Covered Chosen plaintext attack model of security MACs
More informationIdentitybased Encryption with PostChallenge Auxiliary Inputs for Secure Cloud Applications and Sensor Networks
Identitybased Encryption with PostChallenge Auxiliary Inputs for Secure Cloud Applications and Sensor Networks Tsz Hon Yuen  Huawei, Singapore Ye Zhang  Pennsylvania State University, USA Siu Ming
More informationTrading OneWayness against ChosenCiphertext Security in FactoringBased Encryption
Trading OneWayness against ChosenCiphertext Security in FactoringBased Encryption Pascal Paillier 1 and Jorge L. Villar 2 1 Cryptography Group, Security Labs, Gemalto pascal.paillier@gemalto.com 2 Departament
More informationComputational Soundness of Symbolic Security and Implicit Complexity
Computational Soundness of Symbolic Security and Implicit Complexity Bruce Kapron Computer Science Department University of Victoria Victoria, British Columbia NII Shonan Meeting, November 37, 2013 Overview
More informationIdentityBased Encryption from the Weil Pairing
Appears in SIAM J. of Computing, Vol. 32, No. 3, pp. 586615, 2003. An extended abstract of this paper appears in the Proceedings of Crypto 2001, volume 2139 of Lecture Notes in Computer Science, pages
More informationMessage Authentication Codes 133
Message Authentication Codes 133 CLAIM 4.8 Pr[Macforge A,Π (n) = 1 NewBlock] is negligible. We construct a probabilistic polynomialtime adversary A who attacks the fixedlength MAC Π and succeeds in
More informationOn the Security of the Tor Authentication Protocol
On the Security of the Tor Authentication Protocol Ian Goldberg David R. Cheriton School of Computer Science, University of Waterloo, 00 University Ave W, Waterloo, ON NL 3G1 iang@cs.uwaterloo.ca Abstract.
More informationSecuring Remote Access Inside Wireless Mesh Networks
This is the full version of the paper which appears in: Information Security Applications: 10th International Workshop, WISA 2009, Busan, Korea, August 2527, 2009. H. Y. Youm, M. Yung (Eds.) SpringerVerlag,
More informationOverview of PublicKey Cryptography
CS 361S Overview of PublicKey Cryptography Vitaly Shmatikov slide 1 Reading Assignment Kaufman 6.16 slide 2 PublicKey Cryptography public key public key? private key Alice Bob Given: Everybody knows
More informationOn the Security of the CCM Encryption Mode and of a Slight Variant
On the Security of the CCM Encryption Mode and of a Slight Variant PierreAlain Fouque 1 and Gwenaëlle Martinet 2 and Frédéric Valette 3 and Sébastien Zimmer 1 1 École normale supérieure, 45 rue d Ulm,
More informationProvably Secure TimedRelease Public Key Encryption
Provably Secure TimedRelease Public Key Encryption JUNG HEE CHEON Seoul National University, Korea and NICHOLAS HOPPER, YONGDAE KIM and IVAN OSIPKOV University of Minnesota  Twin Cities A timedrelease
More informationAnonymity and Time in PublicKey Encryption
Anonymity and Time in PublicKey Encryption Elizabeth Anne Quaglia Thesis submitted to the University of London for the degree of Doctor of Philosophy Information Security Group Department of Mathematics
More informationFuzzy IdentityBased Encryption
Fuzzy IdentityBased Encryption Janek Jochheim June 20th 2013 Overview Overview Motivation (Fuzzy) IdentityBased Encryption Formal definition Security Idea Ingredients Construction Security Extensions
More informationUniversal Padding Schemes for RSA
Universal Padding Schemes for RSA JeanSébastien Coron, Marc Joye, David Naccache, and Pascal Paillier Gemplus Card International, France {jeansebastien.coron, marc.joye, david.naccache, pascal.paillier}@gemplus.com
More informationChapter 16: Authentication in Distributed System
Chapter 16: Authentication in Distributed System Ajay Kshemkalyani and Mukesh Singhal Distributed Computing: Principles, Algorithms, and Systems Cambridge University Press A. Kshemkalyani and M. Singhal
More informationAuthenticated Encryption in SSH: Provably Fixing the SSH Binary Packet Protocol
Authenticated Encryption in SSH: Provably Fixing the SSH Binary Packet Protocol Mihir Bellare UC San Diego mihir@cs.ucsd.edu Tadayoshi Kohno UC San Diego tkohno@cs.ucsd.edu Chanathip Namprempre Thammasat
More informationCryptosystems. Bob wants to send a message M to Alice. Symmetric ciphers: Bob and Alice both share a secret key, K.
Cryptosystems Bob wants to send a message M to Alice. Symmetric ciphers: Bob and Alice both share a secret key, K. C= E(M, K), Bob sends C Alice receives C, M=D(C,K) Use the same key to decrypt. Public
More informationCapture Resilient ElGamal Signature Protocols
Capture Resilient ElGamal Signature Protocols Hüseyin Acan 1, Kamer Kaya 2,, and Ali Aydın Selçuk 2 1 Bilkent University, Department of Mathematics acan@fen.bilkent.edu.tr 2 Bilkent University, Department
More informationSymmetric Crypto MAC. PierreAlain Fouque
Symmetric Crypto MAC PierreAlain Fouque Birthday Paradox In a set of D elements, by picking at random D elements, we have with high probability a collision two elements are equal D=365, about 23 people
More information36 Toward Realizing PrivacyPreserving IPTraceback
36 Toward Realizing PrivacyPreserving IPTraceback The IPtraceback technology enables us to trace widely spread illegal users on Internet. However, to deploy this attractive technology, some problems
More informationCryptography Overview
Cryptography Overview Cryptography Is n A tremendous tool n The basis for many security mechanisms Is not n The solution to all security problems n Reliable unless implemented properly n Reliable unless
More informationWildcarded IdentityBased Encryption
Wildcarded IdentityBased Encryption Michel Abdalla 1, James Birkett 2, Dario Catalano 3, Alexander W. Dent 4, John MaloneLee 5, Gregory Neven 6,7, Jacob C. N. Schuldt 8, and Nigel P. Smart 9 1 Ecole
More informationDigital Signatures. Prof. Zeph Grunschlag
Digital Signatures Prof. Zeph Grunschlag (Public Key) Digital Signatures PROBLEM: Alice would like to prove to Bob, Carla, David,... that has really sent them a claimed message. E GOAL: Alice signs each
More informationLecture 2 August 29, 13:40 15:40
Lecture 2 August 29, 13:40 15:40 Publickey encryption with keyword search Anonymous identitybased encryption Identitybased encryption with wildcards Publickey encryption with keyword search & anonymous
More informationDigital Signatures. What are Signature Schemes?
Digital Signatures Debdeep Mukhopadhyay IIT Kharagpur What are Signature Schemes? Provides message integrity in the public key setting Counterparts of the message authentication schemes in the public
More informationTalk announcement please consider attending!
Talk announcement please consider attending! Where: Maurer School of Law, Room 335 When: Thursday, Feb 5, 12PM 1:30PM Speaker: Rafael Pass, Associate Professor, Cornell University, Topic: Reasoning Cryptographically
More informationHow to Formally Model Features of Network Security Protocols
, pp.423432 http://dx.doi.org/10.14257/ijsia How to Formally Model Features of Network Security Protocols Gyesik Lee Dept. of Computer & Web Information Engineering Hankyong National University Anseongsi,
More informationQ: Why security protocols?
Security Protocols Q: Why security protocols? Alice Bob A: To allow reliable communication over an untrusted channel (eg. Internet) 2 Security Protocols are out there Confidentiality Authentication Example:
More informationLecture 15  Digital Signatures
Lecture 15  Digital Signatures Boaz Barak March 29, 2010 Reading KL Book Chapter 12. Review Trapdoor permutations  easy to compute, hard to invert, easy to invert with trapdoor. RSA and Rabin signatures.
More informationNoninteractive and Reusable Nonmalleable Commitment Schemes
Noninteractive and Reusable Nonmalleable Commitment Schemes Ivan Damgård a Jens Groth b June 16, 2003 Abstract We consider nonmalleable (NM) and universally composable (UC) commitment schemes in the
More informationRecongurable Cryptography: A exible approach to longterm security
Recongurable Cryptography: A exible approach to longterm security Julia Hesse and Dennis Hofheinz and Andy Rupp Karlsruhe Institute of Technology, Germany {julia.hesse, dennis.hofheinz, andy.rupp}@kit.edu
More informationFormal Modelling of Network Security Properties (Extended Abstract)
Vol.29 (SecTech 2013), pp.2529 http://dx.doi.org/10.14257/astl.2013.29.05 Formal Modelling of Network Security Properties (Extended Abstract) Gyesik Lee Hankyong National University, Dept. of Computer
More informationQUANTUM COMPUTERS AND CRYPTOGRAPHY. Mark Zhandry Stanford University
QUANTUM COMPUTERS AND CRYPTOGRAPHY Mark Zhandry Stanford University Classical Encryption pk m c = E(pk,m) sk m = D(sk,c) m??? Quantum Computing Attack pk m aka Postquantum Crypto c = E(pk,m) sk m = D(sk,c)
More informationLecture 13: Message Authentication Codes
Lecture 13: Message Authentication Codes Last modified 2015/02/02 In CCA security, the distinguisher can ask the library to decrypt arbitrary ciphertexts of its choosing. Now in addition to the ciphertexts
More informationCIS 5371 Cryptography. 8. Encryption 
CIS 5371 Cryptography p y 8. Encryption  Asymmetric Techniques Textbook encryption algorithms In this chapter, security (confidentiality) is considered in the following sense: Allornothing secrecy.
More informationLecture 9  Message Authentication Codes
Lecture 9  Message Authentication Codes Boaz Barak March 1, 2010 Reading: BonehShoup chapter 6, Sections 9.1 9.3. Data integrity Until now we ve only been interested in protecting secrecy of data. However,
More informationMessage Authentication Code
Message Authentication Code Ali El Kaafarani Mathematical Institute Oxford University 1 of 44 Outline 1 CBCMAC 2 Authenticated Encryption 3 Padding Oracle Attacks 4 Information Theoretic MACs 2 of 44
More informationAn efficient and provably secure public key encryption scheme based on coding theory
SECUITY AND COMMUNICATION NETWOKS Security Comm. Networks (2010) Published online in Wiley Online Library (wileyonlinelibrary.com)..274 ESEACH ATICLE An efficient and provably secure public key encryption
More informationOverview of Cryptographic Tools for Data Security. Murat Kantarcioglu
UT DALLAS Erik Jonsson School of Engineering & Computer Science Overview of Cryptographic Tools for Data Security Murat Kantarcioglu Pag. 1 Purdue University Cryptographic Primitives We will discuss the
More information1 Domain Extension for MACs
CS 127/CSCI E127: Introduction to Cryptography Prof. Salil Vadhan Fall 2013 Reading. Lecture Notes 17: MAC Domain Extension & Digital Signatures KatzLindell Ÿ4.34.4 (2nd ed) and Ÿ12.012.3 (1st ed).
More informationOverview of Symmetric Encryption
CS 361S Overview of Symmetric Encryption Vitaly Shmatikov Reading Assignment Read Kaufman 2.14 and 4.2 slide 2 Basic Problem   ? Given: both parties already know the same secret Goal: send
More informationEfficient and Secure Authenticated Key Exchange Using Weak Passwords
Efficient and Secure Authenticated Key Exchange Using Weak Passwords Jonathan Katz Rafail Ostrovsky Moti Yung Abstract Mutual authentication and authenticated key exchange are fundamental techniques for
More informationIncremental Deterministic PublicKey Encryption
Incremental Deterministic PublicKey Encryption Ilya Mironov Omkant Pandey Omer Reingold Gil Segev Abstract Motivated by applications in large storage systems, we initiate the study of incremental deterministic
More informationCertificate Based Signature Schemes without Pairings or Random Oracles
Certificate Based Signature Schemes without Pairings or Random Oracles p. 1/2 Certificate Based Signature Schemes without Pairings or Random Oracles Joseph K. Liu, Joonsang Baek, Willy Susilo and Jianying
More informationChosenCiphertext Security from IdentityBased Encryption
ChosenCiphertext Security from IdentityBased Encryption Dan Boneh Ran Canetti Shai Halevi Jonathan Katz June 13, 2006 Abstract We propose simple and efficient CCAsecure publickey encryption schemes
More informationAdvanced Cryptography
Family Name:... First Name:... Section:... Advanced Cryptography Final Exam July 18 th, 2006 Start at 9:15, End at 12:00 This document consists of 12 pages. Instructions Electronic devices are not allowed.
More informationDelegation of Cryptographic Servers for CaptureResilient Devices
ACM, 2001. This is the authors' version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version is available at http://doi.acm.org/10.1145/501983.501986.
More informationA Secure RFID Ticket System For Public Transport
A Secure RFID Ticket System For Public Transport Kun Peng and Feng Bao Institute for Infocomm Research, Singapore Abstract. A secure RFID ticket system for public transport is proposed in this paper. It
More informationDistributed Key Generation for Secure Encrypted Deduplication
Distributed Key Generation for Secure Encrypted Deduplication Yitao Duan NetEase Youdao Beijing, China duan@rd.netease.com Abstract. Largescale storage systems often attempt to achieve two seemingly conflicting
More informationA Method for Making PasswordBased Key Exchange Resilient to Server Compromise
A Method for Making PasswordBased Key Exchange Resilient to Server Compromise Craig Gentry 1, Philip MacKenzie 2, and Zulfikar Ramzan 3 1 Stanford University, Palo Alto, CA, USA, cgentry@cs.stanford.edu
More informationVictor Shoup Avi Rubin. fshoup,rubing@bellcore.com. Abstract
Session Key Distribution Using Smart Cards Victor Shoup Avi Rubin Bellcore, 445 South St., Morristown, NJ 07960 fshoup,rubing@bellcore.com Abstract In this paper, we investigate a method by which smart
More informationCryptographic Agility and its Relation to Circular Encryption
Cryptographic Agility and its Relation to Circular Encryption Tolga Acar 1 Mira Belenkiy 2 Mihir Bellare 3 David Cash 4 Abstract We initiate a provablesecurity treatment of cryptographic agility. A primitive
More information1. a. Define the properties of a oneway hash function. (6 marks)
1. a. Define the properties of a oneway hash function. (6 marks) A hash function h maps arbitrary length value x to fixed length value y such that: Hard to reverse. Given value y not feasible to find
More informationthe server that does not allow to treat relational databases. A fundamental question thus becomes what is the best guaranteed security that can be
New Security Models and ProvablySecure Schemes for Basic Query Support in Outsourced Databases Georgios Amanatidis Alexandra Boldyreva Adam O Neill Abstract In this paper, we take a closer look at the
More informationSimplified Security Notions of Direct Anonymous Attestation and a Concrete Scheme from Pairings
Simplified Security Notions of Direct Anonymous Attestation and a Concrete Scheme from Pairings Ernie Brickell Intel Corporation ernie.brickell@intel.com Liqun Chen HP Laboratories liqun.chen@hp.com March
More informationAn Efficient and Secure Data Sharing Framework using Homomorphic Encryption in the Cloud
An Efficient and Secure Data Sharing Framework using Homomorphic Encryption in the Cloud Sanjay Madria Professor and Site Director for NSF I/UCRC Center on NetCentric Software and Systems Missouri University
More informationProof of Freshness: How to efficiently use an online single secure clock to secure shared untrusted memory.
Proof of Freshness: How to efficiently use an online single secure clock to secure shared untrusted memory. Marten van Dijk, Luis F. G. Sarmenta, Charles W. O Donnell, and Srinivas Devadas MIT Computer
More informationIdentityBased Encryption Secure Against ChosenCiphertext Selective Opening Attack
IdentityBased Encryption Secure Against ChosenCiphertext Selective Opening Attack Junzuo Lai, Robert H. Deng, Shengli Liu, Jian Weng, and Yunlei Zhao Shanghai Jiao Tong University, Shanghai 200030, China
More informationA Generic Framework for ThreeFactor Authentication
A Generic Framework for ThreeFactor Authentication Jiangshan Yu 1 Guilin Wang 2 Yi Mu 2 Wei Gao 3 1 School of Computer Science University of Birmingham, UK 2 School of Computer Science and Software Engineering
More informationA CCA2 Secure Variant of the McEliece Cryptosystem
1 A CCA2 Secure Variant of the McEliece Cryptosystem Nico Döttling, Rafael Dowsley, Jörn MüllerQuade and Anderson C. A. Nascimento Abstract The McEliece publicey encryption scheme has become an interesting
More informationSecurity Analysis for Order Preserving Encryption Schemes
Security Analysis for Order Preserving Encryption Schemes Liangliang Xiao University of Texas at Dallas Email: xll052000@utdallas.edu Osbert Bastani Harvard University Email: obastani@fas.harvard.edu ILing
More informationCS558. Network Security. Boston University, Computer Science. Midterm Spring 2014.
CS558. Network Security. Boston University, Computer Science. Midterm Spring 2014. Instructor: Sharon Goldberg March 25, 2014. 9:3010:50 AM. Onesided handwritten aid sheet allowed. No cell phone or calculators
More informationEnsuring Integrity in Cloud Computing via Homomorphic Digital Signatures: new tools and results
Ensuring Integrity in Cloud Computing via Homomorphic Digital Signatures: new tools and results Dario Catalano Dario Fiore Luca Nizzardo University of Catania Italy IMDEA Software Institute Madrid, Spain
More informationLeakageResilient Authentication and Encryption from Symmetric Cryptographic Primitives
LeakageResilient Authentication and Encryption from Symmetric Cryptographic Primitives Olivier Pereira Université catholique de Louvain ICTEAM Crypto Group B1348, Belgium olivier.pereira@uclouvain.be
More informationNetwork Security. Computer Networking Lecture 08. March 19, 2012. HKU SPACE Community College. HKU SPACE CC CN Lecture 08 1/23
Network Security Computer Networking Lecture 08 HKU SPACE Community College March 19, 2012 HKU SPACE CC CN Lecture 08 1/23 Outline Introduction Cryptography Algorithms Secret Key Algorithm Message Digest
More informationSchnorr Signcryption. Combining public key encryption with Schnorr digital signature. Laura Savu, University of Bucharest, Romania
Schnorr Signcryption Combining public key encryption with Schnorr digital signature Laura Savu, University of Bucharest, Romania IT Security for the Next Generation European Cup, Prague 1719 February,
More information