Added QuickDigest5 for MD5 Hashing, added bare bones responding, added Helper namespace, and minor redesign of methods

libs/QuickDigest5/quickdigest5.cpp

@@ -0,0 +1,167 @@
+/*
+ * Copyright (c) 2024 - Nathanne Isip
+ * This file is part of QuickDigest5.
+ * 
+ * N8 is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation, either version 3 of the License,
+ * or (at your option) any later version.
+ * 
+ * N8 is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with N8. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/**
+ * @file QuickDigest5.hpp
+ * @author [Nathanne Isip](https://github.com/nthnn)
+ * @brief A header file for the QuickDigest5 class, a utility for MD5 hashing.
+ * 
+ * This file defines the `QuickDigest5` class, which provides functionalities 
+ * for computing MD5 hashes of strings and files. The class also includes 
+ * static methods for converting the computed hash to a string representation.
+ * 
+ * @note This class is designed as a final class and cannot be inherited.
+ */
+#ifndef QUICKDIGEST5_HPP
+#define QUICKDIGEST5_HPP
+
+#include <cstdint>
+#include <fstream>
+#include <iomanip>
+#include <sstream>
+#include <string>
+#include <vector>
+
+/**
+ * @class QuickDigest5
+ * @brief A utility class for MD5 hashing of strings and files.
+ * 
+ * The `QuickDigest5` class provides methods to compute MD5 hashes 
+ * for input strings and files, as well as converting the hash 
+ * to a hexadecimal string representation. This class encapsulates
+ * the internal MD5 computation logic and exposes static methods 
+ * for ease of use.
+ * 
+ * @note This class is marked `final` and cannot be subclassed.
+ */
+class QuickDigest5 final {
+private:
+    /**
+     * @brief Size of the input in bytes.
+     */
+    uint64_t size;
+
+    /**
+     * @brief Buffer for the MD5 computation.
+     */
+    std::vector<uint32_t> buffer;
+
+    /**
+     * @brief Input data to be processed for MD5 hashing.
+     */
+    std::vector<uint8_t> input;
+
+    /**
+     * @brief Stores the resulting MD5 hash.
+     */
+    std::vector<uint8_t> digest;
+
+    /**
+     * @brief Padding used during MD5 computation.
+     * 
+     * A static array defining the padding values required 
+     * to align the input data to a 512-bit boundary.
+     */
+    static uint8_t padding[64];
+
+    /**
+     * @brief Shift values used during MD5 computation.
+     * 
+     * A static array defining the shift amounts for each 
+     * step of the MD5 algorithm.
+     */
+    static uint32_t shift[64];
+
+    /**
+     * @brief Precomputed sine-derived constants.
+     * 
+     * A static array of constants derived from the fractional part 
+     * of sine values, used in the MD5 algorithm.
+     */
+    static uint32_t sineDerivation[64];
+
+    /**
+     * @brief Finalizes the MD5 computation.
+     * 
+     * This method performs any final transformations required 
+     * to complete the MD5 hash computation.
+     */
+    void finalize();
+
+    /**
+     * @brief Processes a single 512-bit block of input data.
+     * 
+     * @param inputVec A vector containing the input data to process.
+     */
+    void step(const std::vector<uint32_t>& inputVec);
+
+    /**
+     * @brief Updates the internal state with input data.
+     * 
+     * @param inputBuffer A pointer to the input data buffer.
+     * @param inputLength The length of the input data in bytes.
+     */
+    void update(
+        const uint8_t* inputBuffer,
+        size_t inputLength
+    );
+
+protected:
+    /**
+     * @brief Constructs a `QuickDigest5` object.
+     * 
+     * The constructor is protected to prevent direct instantiation. 
+     * Users should rely on the static methods provided by the class.
+     */
+    QuickDigest5();
+
+public:
+    /**
+     * @brief Computes the MD5 hash of a string.
+     * 
+     * @param input The input string to hash.
+     * @return A vector of bytes representing the MD5 hash.
+     */
+    static std::vector<uint8_t> digestString(const std::string& input);
+
+    /**
+     * @brief Computes the MD5 hash of a file.
+     * 
+     * @param filepath The path to the file to hash.
+     * @return A vector of bytes representing the MD5 hash.
+     */
+    static std::vector<uint8_t> digestFile(const std::string& filepath);
+
+    /**
+     * @brief Computes the MD5 hash of a string and returns it as a hex string.
+     * 
+     * @param input The input string to hash.
+     * @return A string representing the MD5 hash in hexadecimal format.
+     */
+    static std::string toHash(const std::string& input);
+
+    /**
+     * @brief Computes the MD5 hash of a file and returns it as a hex string.
+     * 
+     * @param filepath The path to the file to hash.
+     * @return A string representing the MD5 hash in hexadecimal format.
+     */
+    static std::string fileToHash(const std::string& filepath);
+};
+
+#endif