From e17c998a5197136d4eb9bd7e69e19739957a528e Mon Sep 17 00:00:00 2001 From: "Md. Anisul Haque" Date: Thu, 25 May 2023 01:42:35 +0530 Subject: [PATCH] fix: suggested changes --- hashing/sha256.cpp | 212 +++++++++++++++++++++++---------------------- 1 file changed, 110 insertions(+), 102 deletions(-) diff --git a/hashing/sha256.cpp b/hashing/sha256.cpp index a346da8ce..674111a89 100644 --- a/hashing/sha256.cpp +++ b/hashing/sha256.cpp @@ -17,6 +17,7 @@ #include /// For uint8_t, uint32_t and uint64_t data types #include /// For std::setfill and std::setw #include /// For std::stringstream +#include /// For std::move #include /// For std::vector /** @@ -24,6 +25,17 @@ * @brief Hashing algorithms */ namespace hashing { +/** + * @namespace SHA-256 + * @brief Functions for the [SHA-256](https://en.wikipedia.org/wiki/SHA-2) + * algorithm implementation + */ +namespace sha256 { +/** + * @class Hash + * @brief Contains hash array and functions to update it and convert it to a + * hexadecimal string + */ class Hash { // Initialize array of hash values with first 32 bits of the fractional // parts of the square roots of the first 8 primes 2..19 @@ -37,11 +49,91 @@ class Hash { }; /** - * @namespace SHA-256 - * @brief Functions for the [SHA-256](https://en.wikipedia.org/wiki/SHA-2) - * algorithm implementation + * @brief Rotates the bits of a 32-bit unsigned integer + * @param n Integer to rotate + * @param rotate Number of bits to rotate + * @return uint32_t The rotated integer */ -namespace sha256 { +uint32_t right_rotate(uint32_t n, size_t rotate) { + return (n >> rotate) | (n << (32 - rotate)); +} + +/** + * @brief Updates the hash array + * @param blocks Message schedule array + * @return void + */ +void Hash::update(const std::array &blocks) { + // Initialize array of round constants with first 32 bits of the fractional + // parts of the cube roots of the first 64 primes 2..311 + const std::array round_constants = { + 0x428A2F98, 0x71374491, 0xB5C0FBCF, 0xE9B5DBA5, 0x3956C25B, 0x59F111F1, + 0x923F82A4, 0xAB1C5ED5, 0xD807AA98, 0x12835B01, 0x243185BE, 0x550C7DC3, + 0x72BE5D74, 0x80DEB1FE, 0x9BDC06A7, 0xC19BF174, 0xE49B69C1, 0xEFBE4786, + 0x0FC19DC6, 0x240CA1CC, 0x2DE92C6F, 0x4A7484AA, 0x5CB0A9DC, 0x76F988DA, + 0x983E5152, 0xA831C66D, 0xB00327C8, 0xBF597FC7, 0xC6E00BF3, 0xD5A79147, + 0x06CA6351, 0x14292967, 0x27B70A85, 0x2E1B2138, 0x4D2C6DFC, 0x53380D13, + 0x650A7354, 0x766A0ABB, 0x81C2C92E, 0x92722C85, 0xA2BFE8A1, 0xA81A664B, + 0xC24B8B70, 0xC76C51A3, 0xD192E819, 0xD6990624, 0xF40E3585, 0x106AA070, + 0x19A4C116, 0x1E376C08, 0x2748774C, 0x34B0BCB5, 0x391C0CB3, 0x4ED8AA4A, + 0x5B9CCA4F, 0x682E6FF3, 0x748F82EE, 0x78A5636F, 0x84C87814, 0x8CC70208, + 0x90BEFFFA, 0xA4506CEB, 0xBEF9A3F7, 0xC67178F2}; + + // Initialize working variables + auto a = hash[0]; + auto b = hash[1]; + auto c = hash[2]; + auto d = hash[3]; + auto e = hash[4]; + auto f = hash[5]; + auto g = hash[6]; + auto h = hash[7]; + + // Compression function main loop + for (size_t block_num = 0; block_num < 64; ++block_num) { + const auto s1 = + right_rotate(e, 6) ^ right_rotate(e, 11) ^ right_rotate(e, 25); + const auto ch = (e & f) ^ (~e & g); + const auto temp1 = + h + s1 + ch + round_constants[block_num] + blocks[block_num]; + const auto s0 = + right_rotate(a, 2) ^ right_rotate(a, 13) ^ right_rotate(a, 22); + const auto maj = (a & b) ^ (a & c) ^ (b & c); + const auto temp2 = s0 + maj; + + h = g; + g = f; + f = e; + e = d + temp1; + d = c; + c = b; + b = a; + a = temp1 + temp2; + } + + // Update hash values + hash[0] += a; + hash[1] += b; + hash[2] += c; + hash[3] += d; + hash[4] += e; + hash[5] += f; + hash[6] += g; + hash[7] += h; +} + +/** + * @brief Convert the hash to a hexadecimal string + * @return std::string Final hash value + */ +std::string Hash::to_string() const { + std::stringstream ss; + for (size_t i = 0; i < 8; ++i) { + ss << std::hex << std::setfill('0') << std::setw(8) << hash[i]; + } + return ss.str(); +} + /** * @brief Computes size of the padded input * @param input Input string @@ -93,16 +185,6 @@ char get_char(const std::string &input, std::size_t pos) { extract_byte(input_size * 8, padded_input_size - pos - 1)); } -/** - * @brief Rotates the bits of a 32-bit unsigned integer - * @param n Integer to rotate - * @param rotate Number of bits to rotate - * @return uint32_t The rotated integer - */ -uint32_t right_rotate(uint32_t n, size_t rotate) { - return (n >> rotate) | (n << (32 - rotate)); -} - /** * @brief Creates the message schedule array * @param input Input string @@ -156,96 +238,19 @@ std::string sha256(const std::string &input) { return h.to_string(); } } // namespace sha256 - -/** - * @brief Updates the hash array - * @param blocks Message schedule array - * @return void - */ -void Hash::update(const std::array &blocks) { - // Initialize array of round constants with first 32 bits of the fractional - // parts of the cube roots of the first 64 primes 2..311 - const std::array k = { - 0x428A2F98, 0x71374491, 0xB5C0FBCF, 0xE9B5DBA5, 0x3956C25B, 0x59F111F1, - 0x923F82A4, 0xAB1C5ED5, 0xD807AA98, 0x12835B01, 0x243185BE, 0x550C7DC3, - 0x72BE5D74, 0x80DEB1FE, 0x9BDC06A7, 0xC19BF174, 0xE49B69C1, 0xEFBE4786, - 0x0FC19DC6, 0x240CA1CC, 0x2DE92C6F, 0x4A7484AA, 0x5CB0A9DC, 0x76F988DA, - 0x983E5152, 0xA831C66D, 0xB00327C8, 0xBF597FC7, 0xC6E00BF3, 0xD5A79147, - 0x06CA6351, 0x14292967, 0x27B70A85, 0x2E1B2138, 0x4D2C6DFC, 0x53380D13, - 0x650A7354, 0x766A0ABB, 0x81C2C92E, 0x92722C85, 0xA2BFE8A1, 0xA81A664B, - 0xC24B8B70, 0xC76C51A3, 0xD192E819, 0xD6990624, 0xF40E3585, 0x106AA070, - 0x19A4C116, 0x1E376C08, 0x2748774C, 0x34B0BCB5, 0x391C0CB3, 0x4ED8AA4A, - 0x5B9CCA4F, 0x682E6FF3, 0x748F82EE, 0x78A5636F, 0x84C87814, 0x8CC70208, - 0x90BEFFFA, 0xA4506CEB, 0xBEF9A3F7, 0xC67178F2}; - - // Initialize working variables - auto a = hash[0]; - auto b = hash[1]; - auto c = hash[2]; - auto d = hash[3]; - auto e = hash[4]; - auto f = hash[5]; - auto g = hash[6]; - auto h = hash[7]; - - // Compression function main loop - for (size_t block_num = 0; block_num < 64; ++block_num) { - const auto s1 = sha256::right_rotate(e, 6) ^ - sha256::right_rotate(e, 11) ^ - sha256::right_rotate(e, 25); - const auto ch = (e & f) ^ (~e & g); - const auto temp1 = h + s1 + ch + k[block_num] + blocks[block_num]; - const auto s0 = sha256::right_rotate(a, 2) ^ - sha256::right_rotate(a, 13) ^ - sha256::right_rotate(a, 22); - const auto maj = (a & b) ^ (a & c) ^ (b & c); - const auto temp2 = s0 + maj; - - h = g; - g = f; - f = e; - e = d + temp1; - d = c; - c = b; - b = a; - a = temp1 + temp2; - } - - // Update hash values - hash[0] += a; - hash[1] += b; - hash[2] += c; - hash[3] += d; - hash[4] += e; - hash[5] += f; - hash[6] += g; - hash[7] += h; -} - -/** - * @brief Convert the hash to a hexadecimal string - * @return std::string Final hash value - */ -std::string Hash::to_string() const { - std::stringstream ss; - for (size_t i = 0; i < 8; ++i) { - ss << std::hex << std::setfill('0') << std::setw(8) << hash[i]; - } - return ss.str(); -} } // namespace hashing /** * @brief Self-test implementations * @returns void */ -static void test_compute_padded_size() { +void test_compute_padded_size() { assert(hashing::sha256::compute_padded_size(55) == 64); assert(hashing::sha256::compute_padded_size(56) == 128); assert(hashing::sha256::compute_padded_size(130) == 192); } -static void test_extract_byte() { +void test_extract_byte() { assert(hashing::sha256::extract_byte(512, 0) == 0); assert(hashing::sha256::extract_byte(512, 1) == 2); bool exception = false; @@ -257,7 +262,7 @@ static void test_extract_byte() { assert(exception); } -static void test_get_char() { +void test_get_char() { assert(hashing::sha256::get_char("test", 3) == 't'); assert(hashing::sha256::get_char("test", 4) == '\x80'); assert(hashing::sha256::get_char("test", 5) == '\x00'); @@ -271,13 +276,13 @@ static void test_get_char() { assert(exception); } -static void test_right_rotate() { +void test_right_rotate() { assert(hashing::sha256::right_rotate(128, 3) == 16); assert(hashing::sha256::right_rotate(1, 30) == 4); assert(hashing::sha256::right_rotate(6, 30) == 24); } -static void test_sha256() { +void test_sha256() { struct TestCase { const std::string input; const std::string expected_hash; @@ -303,16 +308,19 @@ static void test_sha256() { } } +void test() { + test_compute_padded_size(); + test_extract_byte(); + test_get_char(); + test_right_rotate(); + test_sha256(); +} + /** * @brief Main function * @returns 0 on exit */ int main() { - // Run self-test implementations - test_sha256(); - test_compute_padded_size(); - test_extract_byte(); - test_get_char(); - test_right_rotate(); + test(); // Run self-test implementations return 0; }