Wykład Kryptografia 2005
Topics from the course:
- introduction:
symmetric encryption, asymmetric encryption, applications -- for
confidentiality and authentication,
attack through trial encryptions,
key establishment with asymmetric encryption,
man-in-the-middle attack, hybrid algorithms, hash functions,
conflict free hash functions, bit commitment,
digital signatures based on discrete logarithm problem - ElGamal signatures,
Diffie-Hellman key exchange, key transport - Shamir's algorithm,
Schnorr's proof of knowledge of discrete logarithm
- algebraic foundations: multiplicative groups modulo
n , modulo p, generalized Euclidean algorithm,
reverse element modulo n, Euler Theorem, Chinese Reminder Theorem,
modular exponentiation: basic algorithm,
-
RSA algorithm: soundness of decryption procedure,
primality test of Rabin-Miller, attacks:
common moduli, small public exponent, cyclic attack,
factorization problem:
Floyd's Algorithm, rho-Pollard method,
p-1 Pollard method,
strong prime numbers,
multiplication attack, attack through blinding
- other asymmetric algorithms: Rabin's encryption,
computing square roots modulo p and modulo n
fining square roots and factorization - randomized algorithm,
probabilistic encryption of Goldwasser-Micali,
- symmetric encryption:
encryption modes: ECB, CBC, CFB, OFB, encryption of file systems,
double and triple encryption, attack on double encryption,
Feistel scheme, DES, RC5, AES,
- cryptanalysis: differential cryptanalysis: through faults,
3-round DES, 4-round DES, characteristics, linear cryptanalysis,
saturation attack, side channel attack: reverse engineering,
energy consumption, masking technique, execution time, problems with multiplication
modulo 2 to 16 +1, testing cryptographic hardware and trapdoors for
cryptanalysis
- hashing functions:
hashing based on discrete logarithm,
padding, Rabin scheme, Davies scheme,
overview of SHA-1 construction, idea of attacks
- pseudorandom number generators:
LFSR, A5/1, BBS, unpredictability and unreversability,
- keys: betraying keys and subliminal channels: ElGamal ciphertexts,
Newton channel in ElGamal signatures, kleptography based on discrete logarithm
systems, dangers and countermeasures, key predistribution: subset construction,
user removal schemes based on polynomials,
- signatures: DSS signatures, ring signatures, undeniable signatures,
public key infrastructures: key rings of PGP, X.509, SPKI