A block cipher is an encryption algorithm which encrypts fixed-size blocks of plaintext to same-sized blocks of ciphertext. For good ciphers every bit of the ciphertext block depends on every bit of the plaintext block and every bit of the key.
4
votes
0answers
86 views
Pseudo preimage for a hash made from a cipher
Consider the Miyaguchi–Preneel construction:
$H_0 = E(0,m_0) \oplus m_0$ (0 here means a vector filled with zeros)
$H_1 = E(H_0,m_1) \oplus H_0 \oplus m_1$
where $E(K,M)$ is a block cipher (for ...
2
votes
0answers
77 views
Are there any secure commutative ciphers?
This answer lists two commutative cipher algorithms - Pohlig-Hellman and SRA. However, they don't appear to be too secure.
My question is, here there any commutative ciphers out there that are secure ...