• Instructor:

  • Logistics:

  • Class timing: Tuesday (11:00 am - 12:30 pm) and Thursday (6:30 pm - 8:00 pm)
  • Venue: CSA 252

  • Course Description (1st half) :

One way Functions (Permutations), Hard-core Predicates, Pseudo-random Generators, (Strong) Pseudo-random Functions (Permutations)

Secret Key Encryptions (SKE): Various security notions such as perfect security, semantic security, indistinguishability based Security, CPA Security, CCA Security, Constructions, Block Cipher Mode of Operations.

Message Authentication Codes (MAC): Various Secrity notions such as CMA Security, (weak/strong) CMVA security, Domain Extension, CBC-MAC.

Advanced Encryption Schemes: Authenticated Encryptions.

Introduction to Secure Computation (Yao's 2PC protocol and circuit garbling)

  • Grading:

The course evaluation for the first half will be done as follows (most likely)

  • Scribe (10): Every student must scribe at least one lecture. The scribe submission deadline is one week after the corresponding lecture. The template tex file for a scribe can be downloaded from here. As you have guessed, the submission must be in Latex. Get first-hand ideas about scribing from various course webpages. Such as this.
  • Final Exam (40): Date and Time: 1st March'17, 5:30pm - 8:30pm

  • Reading Material and References:

Reference Books:

  • Jonathan Katz and Yehuda Lindell, Introduction to Modern Cryptography, second edition 2014, CRC Press. You should definitely have a copy of this book. We will mostly follow this book.
  • Cryptography: Theory and Practice by Douglas Stinson, Third edition, CRC Press.
  • Handbook of Applied Cryptography by Alfred Menezes, Paul Oorschot and Scott Vanstone. Available Online .
  • Foundations of Cryptography by Oded Goldreich. Available Online .
  • Cryptography, An Introduction by Nigel Smart. Available Online .
Some useful Course Notes/Lectures:

  • Other Info:

  • Office Hours: TBA

Lecture Details

Lecture # and Date
Lecture contents
Slides / Reading material (KL: Katz-Lindell 2nd Edition)
Scribes
Problem Set (KL: Katz-Lindell 2nd Edition)
Lecture 1 (05-01-2017) Introduction, Classical Crypto vs. Modern Crypto, Three Pillars of Modern crypto (definition + assumption + proof), Classical ciphers and pitfalls. Inroad towards Modern Crypto. [pptx] / Chapter 1 of KL Chapter 1 Questions
Lecture 2 (10-01-2017) Perfect Security: Definition, Construction (Vernam Cipher), Proof; Drawbacks of OTP [pptx] / Chapter 2 of KL Swati [ ], Ananth [ ]
Lecture 3 (12-01-2017) Proof for the inherent drawback on key length, Equivalent Alternative Definitions for Perfect Security, Shannon's Theorem, Relaxing perfect security. Introduction to Computational Security. [pptx] / Chapter 2 of KL Prasanth [], Ashok [] Chapter 2 Questions from KL
Lecture 4 (17-01-2017) Computational Security: Necessity of the relaxations in threat and break models. Definitions of PPT and negligible functions, Security Parameter. Sematic Security, Indistinguishability-based Security and its variant. [pptx / KL pp. 43-59 Gourav [ ], Shravan [ ]
Lecture 5 (19-01-2017) Pseudo-random Generators (PRGs): Definition, No PRG against unbounded distinguisher; coa-secure Scheme from PRG, Proof by Reduction, Proof of coa-secure scheme; coa-mult security and proof that no deterministic enc can be coa-mult secure. [pptx] /KL pp. 60-72 Akshay [ ], Akash[ ], Philips [ ] KL 3.1-3.8
Lecture 6 (24-01-2017) CPA, cpa security for single and multiple messages, why cpa security stronger than coa-mult. Need of randomized encryption scheme, PRF, definition, PRP, Strong PRP. [pptx] /KL pp. 73-81 Basheer [], Akanksha [], Arun. KL 3.9-3.17
Lecture 7 (31-01-2017) cpa-secure scheme from PRF, proof of security, Block-cipher mode of operations: ECB, CBC, OFB, CTR [pptx]/ KL 82-95 Urvashi [ ],Nidhin [], Megha KL 3.19-3.23, 3.25-3.27, 3.29
Lecture 8 (02-02-2017) Chosen Ciphertext Attacks (CCA), Padding Oracle Attack on CBC-mode encryption, cca-security, Break of cpa-secure (PRF-based) schemes. Malleability. Introduction to MACs. Issues of Message Authetication and Message Integrity. (strong and weak) cma-security for MACs. [pptx] / KL 96-100,107-116. Amit [], Nitish [] KL 3.18, 3.28
Lecture 9 (09-02-2017) MAC, Various Security Notions (cma, strong cma, cmva, strong cmva), cma-secure MAC from PRF, Domain Extension, Authenticated Encryption: Definition (cpa-security + Cipher Integrity), Construction from cpa-secure SKE and scma-secure MAC. Three approaches: authenticate-and-encrypt, authenticate-then-encrypt, encrypt-then-authenticate. [pptx] / KL 389-399,405-404, 387-89 Shivam [], Ravi, Razi Ur Rehman KL Chapter 4 questions
Lecture 10 (10-02-2016) Authenticated Encryption: Definition (cpa-security + Cipher Integrity), Construction from cpa-secure SKE and scma-secure MAC. Three approaches: authenticate-and-encrypt, authenticate-then-encrypt, encrypt-then-authenticate, AE implies CCA security. [pptx] Anil [], Adhithya [], Soumalya [] KL Chapter 4 questions
Lecture 11 (14-02-2017) PRG implies PRF (GGM Tree Construction). Hybrid Arguments. Proof. [pptx] [], [] , [ ], [] KL 7.14,7.15
Lecture 12 (26-02-2017) One-way Functions (OWF), One-way Permutations (OWP), Hard-core Predicates, OWF (OWP) implies Hard-core Predicates (Goldreich-Levin Theorem). One-way Functions (OWP) and Hard-core Predicates implies PRG. [pptx] [ ], [ ], [ ], [ ], [ ] KL Chapter 7 Questions
Lecture 13 (21-02-2016) Yao's 2PC Protocol, Circuit Garbling [pptx] [ ],[] KL Chapter 7 Questions

Tutorial Details

Tutorial 1 (07-01-2017): Vigenere Cipher Cryptanalysis, Question Set 1 [pdf]

Tutorial 2 (13-01-2017): Cryptanalysis of OTP when key is reused, Question Set 2 [pdf]

Tutorial 3 (20-01-2017): Question Set 3 [pdf]

Tutorial 4 (27-01-2017): Question Set 4 [pdf]

Tutorial 5 (03-02-2017): Question Set 5 [pdf]

Tutorial 6 (10-02-2017): AE implies CCA-security. Question Set 6 [pdf]