\section{Introduction} \texttt{libft\_ssl} is a C library implementing cryptographic hash functions from scratch. A cryptographic hash function maps an arbitrary-length input to a fixed-size digest. This operation is deterministic and one-way: it is computationally infeasible to recover the original input from its digest. The library currently implements the following algorithms: \begin{itemize} \item \textbf{MD5} - produces a 128-bit digest. \item \textbf{SHA-256} - produces a 256-bit digest. \item \textbf{Whirlpool} - produces a 512-bit digest. \end{itemize} These functions are commonly used for data integrity verification, digital signatures, and \textbf{M}essage \textbf{A}uthentication \textbf{C}ode\textbf{s} (MACs). \newpage