Message Authentication Codes (MAC) represent a cryptographic primitive in symmetric cryptography designed to ensure message integrity and authenticity via unforgeability under chosen-message attacks (UF-CMA). Theoretical security relies on the reduction from Pseudorandom Function (PRF) properties, where any UF-CM-secure construction derived from a secure PRF is inherently protected against forgery. Furthermore, domain extension techniques transform fixed-input-length block ciphers into variable-input-length constructions while managing birthday attacks through output length and specific padding schemes.
Message Authentication Codes (MAC) represent a cryptographic primitive in symmetric cryptography designed to ensure message integrity and authenticity via unforgeability under chosen-message attacks …