GHASH function – Block Ciphers

Analyzing the TLS record, Exams of IT, GHASH function, IT Certification, Plaintext integrity, Security of generic composition, TLS Record protocol

CTR mode – Block Ciphers and Their Modes of Operation

08/31/202408/31/2024

Posted by Whitney Koehler

14.4.5 CTR mode The Counter (CTR) mode, illustrated in Figure 14.12, is a mode of operation that applies the underlying block cipher f to generate a key stream that is subsequently used for

Block ciphers in TLS 1.3 – Block Ciphers and Their Modes of Operation

04/15/202408/31/2024

Posted by Whitney Koehler

14.5 Block ciphers in TLS 1.3 In TLS, block ciphers are used for protecting the confidentiality and integrity of data transmitted over the TLS Record layer. More precisely, a block cipher is used for

Indistinguishability under a chosen-ciphertext attack – Authenticated Encryption

01/18/202408/31/2024

Posted by Whitney Koehler

15.1.2 Indistinguishability under a chosen-ciphertext attack Chosen-Ciphertext Attack (CCA) is a more powerful attack than a chosen-plaintext attack. Recall that in a chosen-plaintext attack Eve is

Security of generic composition – Authenticated Encryption

05/15/202308/31/2024

Posted by Whitney Koehler

15.3 Security of generic composition In their seminal publication Authenticated Encryption: Relations among Notions and Analysis of the Generic Composition Paradigm , Bellare and Namprempre analyze

Authenticated encryption with associated data – Authenticated Encryption

03/20/202308/31/2024

Posted by Whitney Koehler

15.4.1 Authenticated encryption with associated data In this section, by associated data we mean any data that should be authenticated but not encrypted. There are some scenarios where it is useful

Avoiding predictability with nonces – Authenticated Encryption

01/20/202308/31/2024

Posted by Whitney Koehler

15.4.2 Avoiding predictability with nonces Recall that an encryption scheme is called probabilistic if it returns different ciphertexts when the same plaintext is repeatedly encrypted. Otherwise, an

Authenticated encryption with CCM – Authenticated Encryption

12/15/202208/31/2024

Posted by Whitney Koehler

15.5.1 Authenticated encryption with CCM To apply CCM, sender Alice must provide the following four inputs: How to perform authenticated encryption with CCM based on these four inputs is illustrated

GHASH function – The Galois Counter Mode

06/05/202208/31/2024

Posted by Whitney Koehler

16.1.2 GHASH function GCM’s authentication mechanism is based on a hash function called GHASH. The function contains a multiplication by a fixed parameter H within GCM’s 𝔽2128 field.

GCM security – The Galois Counter Mode

03/05/202208/31/2024

Posted by Whitney Koehler

16.2 GCM security GCM’s biggest security risk is its fragility in case of nonce repetition. NIST’s GCM standard requires the following: The probability that the authenticated encryption function

GCM performance – The Galois Counter Mode

01/20/202208/31/2024

Posted by Whitney Koehler

16.3 GCM performance There is an old saying among cryptographers that the real challenge is not to design a secure algorithm, but one that is secure and fast. While this is typically said somewhat