SHA C++ Implementation

This repository contains a C++ implementation of various SHA (Secure Hash Algorithm) functions. The header file includes the following algorithms:

• SHA-256: Produces a 256-bit hash value.
• SHA-224: A truncated version of SHA-256 that produces a 224-bit hash value.
• SHA-512: Produces a 512-bit hash value.
• SHA-384: A truncated version of SHA-512 that produces a 384-bit hash value.
• SHA-512/224: A variant of SHA-512 that produces a 224-bit hash value.
• SHA-512/256: A variant of SHA-512 that produces a 256-bit hash value.

Classes

SHABase

The SHABase class provides common methods and utilities used by the SHA algorithms.

Protected Methods:

• to_bit_string(Type number): Converts a number to a bit string representation.
• to_integral(const char* data): Converts a character array to an integral type representation.
• to_integral_vector(const std::string& preprocessed_data): Converts a preprocessed string to a vector of integral types.
• to_hex(const std::string& str): Converts a string to its hexadecimal representation.
• to_string(const Type* hash_digest): Converts an array of hash values to a string representation.
• ch(Type x, Type y, Type z): Computes the 'ch' function used in hash computations.
• maj(Type x, Type y, Type z): Computes the 'maj' function used in hash computations.
• RotR(Type a, short n): Performs a right bitwise rotation.
• ShR(Type a, short n): Performs a right arithmetic shift.

SHA256

The SHA256 class implements the SHA-256 hashing function.

Public Methods:

• std::string hash(const char* data): Computes the SHA-256 hash of the input data.

SHA224

The SHA224 class implements the SHA-224 hashing function.

Public Methods:

• std::string hash(const char* data): Computes a SHA-224 hash from the input data.

SHA512

The SHA512 class implements the SHA-512 hashing function.

Public Methods:

• std::string hash(const char* data): Computes the SHA-512 hash of the input data.

Disclaimer: While the SHA-512 algorithm theoretically supports hashing up to 2¹²⁸ - 1 bits of data, this implementation is limited to handling up to 2⁶⁴ -1 bits of data.

SHA384

The SHA384 class implements the SHA-384 hashing function.

Public Methods:

• std::string hash(const char* data): Computes a SHA-384 hash from the input data.

SHA512_224

The SHA512_224 class implements the SHA-512/224 hashing function.

Public Methods:

• std::string hash(const char* data): Computes a SHA-512/224 hash from the input data.

SHA512_256

The SHA512_256 class implements the SHA-512/256 hashing function.

Public Methods:

• std::string hash(const char* data): Computes a SHA-512/256 hash from the input data.

Usage

To use the SHA hashing functions, include the header file in your C++ project and create instances of the desired SHA class. Call the hash method with the input data to obtain the hash value.

#include<iostream>
#include "sha.h"

int main() {
    sha::SHA256 sha256;
    std::string hash = sha256.hash("your data here");
    std::cout << "SHA-256 hash: " << hash << std::endl;
    return 0;
}

Benchmarking

To benchmark the performance of the SHA implementations, use the provided benchmarking executable. It measures the time taken to compute hashes for different SHA algorithms.

1. Build the Benchmarking Executable:

make benchmark

2. Run the Benchmark:

build/benchmark/sha_benchmark

Testing

To test the SHA implementations, use the provided test executable. It verifies the correctness of the hashing functions using predefined test cases.

1. Build the Test Executable:

make unit_tests

2. Run the Tests:

build/test/test_sha