Wyklad Kryptografia 2006
Topics from the course:
-
symmetric encryption:
one-time pad, perfect security, stream ciphers and pseudorandom
bit generators, A5/1 generator, substitution ciphers and frequency analysis,
block ciphers: Feistel construction, open design principle, encryption modes:
CBC, CFB, encryption of disks, double and triple encryption,
design of DES, some design criteria, differential cryptanalysis: fault analysis,3-round and 4-round DES (characteristics), characteristics - general approach,
linear cryptanalysis, Two-fish and saturation attack, RC4 and RC5, Rijndael,
- asymmetric encryption: usage for data confidentiality and for authentication,
attack through trial encryptions, basics of discrete log systems: Zp, inverting elements with generalized Euclidean algorithm, generators, Descrete Logarithm Problem, ElGamal enryption, basics for RSA: Chinese Remainder Theorem, Z_n^*,
RSA encryption and decryption, factorization problem, Floyd's method,
rho-Pollard, p-1 Pollard, square roots for RSA numbers, primality test of Rabin-Miller,
generating RSA parameters, efficient modular exponentiation, attacks:
common moduli, small public exponent, cyclic attack,
multiplication attack, hard bit of RSA, Blum-GOldwasser probabilistic encryption,
- key management:
key establishment with asymmetric encryption,
Diffie-Hellman, man-in-the-middle attack, MTI, STI,
self-certifying public keys, Shamir's algorithm
- digital signatures: RSA signatures, multiplicative attack,
redundancy functions and
hash functions, ISO/IEC 9796 redundancy function,
ElGamal signature, attack on ElGamal when size of the signature
components not checked, problems with weak randomness, DSA,
Schnorr scheme, signing bit commitments,
- secret sharing : XOR, threshold schemes with polynomials,
information about general access structures,
- malicious cryptography: subliminal channel, kleptographic channel
- authentication: storing keys in UNIX and dictionary attacks,
passphrases, Lamport's scheme, mutual authentication protocol (of smart cards)