CMSC 456 Introduction to Cryptography

Slides:



Advertisements
Similar presentations
CMSC 414 Computer and Network Security Lecture 4 Jonathan Katz.
Advertisements

CMSC 414 Computer (and Network) Security Lecture 4 Jonathan Katz.
CS555Topic 191 Cryptography CS 555 Topic 19: Formalization of Public Key Encrpytion.
1 Introduction CSE 5351: Introduction to cryptography Reading assignment: Chapter 1 of Katz & Lindell.
Web Security for Network and System Administrators1 Chapter 4 Encryption.
CMSC 414 Computer (and Network) Security Lecture 5 Jonathan Katz.
CMSC 414 Computer and Network Security Lecture 6 Jonathan Katz.
CMSC 414 Computer (and Network) Security Lecture 9 Jonathan Katz.
CMSC 414 Computer and Network Security Lecture 3 Jonathan Katz.
CMSC 414 Computer (and Network) Security Lecture 2 Jonathan Katz.
CMSC 414 Computer and Network Security Lecture 7 Jonathan Katz.
Chapter 5 Cryptography Protecting principals communication in systems.
CMSC 414 Computer and Network Security Lecture 5 Jonathan Katz.
CMSC 414 Computer and Network Security Lecture 4 Jonathan Katz.
Henric Johnson1 Chapter3 Public-Key Cryptography and Message Authentication Henric Johnson Blekinge Institute of Technology, Sweden
CMSC 414 Computer and Network Security Lecture 9 Jonathan Katz.
Secure Hashing and DSS Sultan Almuhammadi ICS 454 Principles of Cryptography.
Cryptography and Network Security Chapter 12 Fourth Edition by William Stallings Lecture slides by Lawrie Brown.
CMSC 414 Computer and Network Security Lecture 6 Jonathan Katz.
CMSC 414 Computer and Network Security Lecture 4 Jonathan Katz.
CMSC 414 Computer and Network Security Lecture 7 Jonathan Katz.
Fall 2010/Lecture 311 CS 426 (Fall 2010) Public Key Encryption and Digital Signatures.
What is Cryptography? Definition: The science or study of the techniques of secret writing, esp. code and cipher systems, methods, and the like Google.
CMSC 414 Computer and Network Security Lecture 3 Jonathan Katz.
CMSC 414 Computer and Network Security Lecture 5 Jonathan Katz.
Lecture 4 Cryptographic Tools (cont) modified from slides of Lawrie Brown.
1 CSE 5351: Introduction to Cryptography Ten H. Lai Spring 2015 MW 3:55-5:15 PM, CL133.
Foundations of Cryptography Rahul Jain CS6209, Jan – April 2011
1 Chapter 4 Encryption. 2 Objectives In this chapter, you will: Learn the basics of encryption technology Recognize popular symmetric encryption algorithms.
CMSC 414 Computer and Network Security Lecture 3 Jonathan Katz.
1 Public-Key Cryptography and Message Authentication Ola Flygt Växjö University, Sweden
Lecture slides prepared for “Computer Security: Principles and Practice”, 2/e, by William Stallings and Lawrie Brown, Chapter 21 “Public-Key Cryptography.
Chi-Cheng Lin, Winona State University CS 313 Introduction to Computer Networking & Telecommunication Network Security (A Very Brief Introduction)
CMSC 414 Computer and Network Security Lecture 6 Jonathan Katz.
I-4 security.
© 2006 Cisco Systems, Inc. All rights reserved. Network Security 2 Module 3: VPN and Encryption Technology.
Introduction to Stream Cipher Sayed Mahdi Mohammad Hasanzadeh Spring 2004.
CS 4/585: Cryptography Tom Shrimpton FAB
Midterm Review Cryptography & Network Security
CS526: Information Security Prof. Sam Wagstaff September 16, 2003 Cryptography Basics.
Cryptographic Hash Functions Message Authentication Digital Signatures.
Lecture 4.1: Hash Functions, and Message Authentication Codes CS 436/636/736 Spring 2015 Nitesh Saxena.
1 Overview of Cryptography. Contents Introduction Symmetric-key cryptography Block ciphers Symmetric-key algorithms Cipher block modes Stream cipher Public-key.
Basic Cryptography 1. What is cryptography? Cryptography is a mathematical method of protecting information –Cryptography is part of, but not equal to,
Chapter 21 Public-Key Cryptography and Message Authentication.
CMSC 414 Computer and Network Security Lecture 5 Jonathan Katz.
Computer Security: Principles and Practice First Edition by William Stallings and Lawrie Brown Lecture slides by Lawrie Brown Chapter 2 – Cryptographic.
Chapter 4 Message Authentication MSc. NGUYEN CAO DAT Dr. TRAN VAN HOAI 1.
Cryptography Chapter 7 Part 3 Pages 812 to 833. Symmetric Cryptography Security Services – Only confidentiality, not authentication or non- repudiation.
A Quick Tour of Cryptographic Primitives Anupam Datta CMU Fall A: Foundations of Security and Privacy.
CMSC 414 Computer and Network Security Lecture 9 Jonathan Katz.
1 CIS 5371 Cryptography 4. Message Authentication Codes B ased on: Jonathan Katz and Yehuda Lindell Introduction to Modern Cryptography.
Class 4 Asymmetric Cryptography and Trusting Internal Components CIS 755: Advanced Computer Security Spring 2014 Eugene Vasserman
Cryptography 1 Crypto Cryptography 2 Crypto  Cryptology  The art and science of making and breaking “secret codes”  Cryptography  making “secret.
Class 3 Cryptography Refresher II CIS 755: Advanced Computer Security Spring 2014 Eugene Vasserman
Exam 1 Review CS461/ECE422 Fall Exam guidelines A single page of supplementary notes is allowed  8.5x11. Both sides. Write as small as you like.
ICOM 5995 (crypto) - Noack Crypto - Administrivia Prontuario - Please time-share and ask questions Info is in my homepage amadeus.uprm.edu/~noack/ Make.
Class 3 Cryptography Refresher II CIS 755: Advanced Computer Security Spring 2015 Eugene Vasserman
1 Symmetric-Key Encryption CSE 5351: Introduction to Cryptography Reading assignment: Chapter 2 Chapter 3 (sections ) You may skip proofs, but are.
CS555Spring 2012/Topic 71 Cryptography CS 555 Topic 7: Stream Ciphers and CPA Security.
Lecture 4.1: Hash Functions, and Message Authentication Codes CS 436/636/736 Spring 2014 Nitesh Saxena.
CS555Spring 2012/Topic 151 Cryptography CS 555 Topic 15: HMAC, Combining Encryption & Authentication.
Course summary COS 433: Crptography -Spring 2010 Boaz Barak.
Cryptography Lecture 12.
CMSC 414 Computer and Network Security Lecture 3
Cryptography Lecture 12.
Cryptography Lecture 11.
Cryptography Lecture 27.
Presentation transcript:

CMSC 456 Introduction to Cryptography Jonathan Katz

Overview of exam The exam is cumulative More emphasis on material covered in the second half of the semester Focus on understanding and application, less on being clever Please read instructions, and describe attacks or constructions clearly and unambiguously

Chapter 1 Historical private-key encryption schemes Why did we talk about these? Modern cryptography Definitions Assumptions Proofs

Chapter 2 Perfect secrecy The one-time pad Limitations of perfect secrecy Key as long as the message Key can only be used once No security against chosen-plaintext attacks Need pre-shared key!

Chapter 3a Computational security Private-key encryption Definitions: Indistinguishability in the presence of an eavesdropper Multiple-message indistinguishability CPA-security CCA-security

Chapter 3b Primitives Encryption schemes Pseudorandom generators Pseudorandom functions (block ciphers) AES, 3DES, (DES) Encryption schemes “Pseudo one-time pad” Deterministic encryption? Basic CPA-secure encryption scheme Modes of encryption

Chapter 4a Message authentication codes, defining security Collision-resistant hash functions SHA-1 Birthday attacks (other applications?) Constructions Basic construction for short messages HMAC CBC-MAC

Chapter 4b Privacy + message authentication, CCA-security Encrypt-then-authenticate Why are the other alternatives problematic?

Chapter 5 Definition of pseudorandomness… Concrete security requirements Substitution-permutation networks Attacks on reduced-round SPNs AES Feistel networks Attacks on reduced-round Feistel networks DES Increasing key length 3DES Meet-in-the-middle attacks

Chapter 7 Modular arithmetic, group theory, cyclic groups, generators ZN, Z*N, (N) Generating random primes Factoring assumption, RSA assumption, discrete logarithm assumption, Diffie-Hellman assumptions One-way functions, examples

Chapter 9 What are the limitations of private-key crypto? Why did we bother studying private-key crypto at all? Key exchange Definition of security Diffie-Hellman key exchange

Chapter 10a Public-key encryption Definitions Hybrid encryption Indistinguishability = CPA-security Deterministic encryption? CCA-security Why important Hybrid encryption

Chapter 10b RSA encryption El Gamal encryption Textbook RSA Padded RSA Why is it insecure? Padded RSA El Gamal encryption What assumption is it based on?

Chapter 12a Digital signatures Definition of security RSA signatures Advantages relative to MACs? Definition of security RSA signatures Textbook RSA Why is it insecure? Hashed RSA

Chapter 12b Hash-and-sign 1-time signatures, Lamport’s scheme PKI, certificates

The real world Pseudorandom functions (block ciphers) AES, 3DES Collision-resistant hash function SHA-1, others (NIST competition) Private-key encryption E.g., CBC mode, others for CPA-security Encrypt-then-authenticate for CCA-security Message authentication codes HMAC, CBC-MAC, others

The real world Key exchange Public-key encryption Signature schemes (Authenticated) Diffie-Hellman Public-key encryption (Variants of) padded RSA El Gamal encryption CCA-secure schemes Signature schemes (Variants of) hashed RSA DSS (we did not cover)