diff --git a/main.cpp b/main.cpp new file mode 100644 index 0000000..364eaab --- /dev/null +++ b/main.cpp @@ -0,0 +1,360 @@ +#include +#include +#include +#include +#include +using namespace std; + +// AES S盒(完整256个值) +const array s_box = { + 0x63, 0x7C, 0x77, 0x7B, 0xF2, 0x6B, 0x6F, 0xC5, 0x30, 0x01, 0x67, 0x2B, 0xFE, 0xD7, 0xAB, 0x76, + 0xCA, 0x82, 0xC9, 0x7D, 0xFA, 0x59, 0x47, 0xF0, 0xAD, 0xD4, 0xA2, 0xAF, 0x9C, 0xA4, 0x72, 0xC0, + 0xB7, 0xFD, 0x93, 0x26, 0x36, 0x3F, 0xF7, 0xCC, 0x34, 0xA5, 0xE5, 0xF1, 0x71, 0xD8, 0x31, 0x15, + 0x04, 0xC7, 0x23, 0xC3, 0x18, 0x96, 0x05, 0x9A, 0x07, 0x12, 0x80, 0xE2, 0xEB, 0x27, 0xB2, 0x75, + 0x09, 0x83, 0x2C, 0x1A, 0x1B, 0x6E, 0x5A, 0xA0, 0x52, 0x3B, 0xD6, 0xB3, 0x29, 0xE3, 0x2F, 0x84, + 0x53, 0xD1, 0x00, 0xED, 0x20, 0xFC, 0xB1, 0x5B, 0x6A, 0xCB, 0xBE, 0x39, 0x4A, 0x4C, 0x58, 0xCF, + 0xD0, 0xEF, 0xAA, 0xFB, 0x43, 0x4D, 0x33, 0x85, 0x45, 0xF9, 0x02, 0x7F, 0x50, 0x3C, 0x9F, 0xA8, + 0x51, 0xA3, 0x40, 0x8F, 0x92, 0x9D, 0x38, 0xF5, 0xBC, 0xB6, 0xDA, 0x21, 0x10, 0xFF, 0xF3, 0xD2, + 0xCD, 0x0C, 0x13, 0xEC, 0x5F, 0x97, 0x44, 0x17, 0xC4, 0xA7, 0x7E, 0x3D, 0x64, 0x5D, 0x19, 0x73, + 0x60, 0x81, 0x4F, 0xDC, 0x22, 0x2A, 0x90, 0x88, 0x46, 0xEE, 0xB8, 0x14, 0xDE, 0x5E, 0x0B, 0xDB, + 0xE0, 0x32, 0x3A, 0x0A, 0x49, 0x06, 0x24, 0x5C, 0xC2, 0xD3, 0xAC, 0x62, 0x91, 0x95, 0xE4, 0x79, + 0xE7, 0xC8, 0x37, 0x6D, 0x8D, 0xD5, 0x4E, 0xA9, 0x6C, 0x56, 0xF4, 0xEA, 0x65, 0x7A, 0xAE, 0x08, + 0xBA, 0x78, 0x25, 0x2E, 0x1C, 0xA6, 0xB4, 0xC6, 0xE8, 0xDD, 0x74, 0x1F, 0x4B, 0xBD, 0x8B, 0x8A, + 0x70, 0x3E, 0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E, 0x61, 0x35, 0x57, 0xB9, 0x86, 0xC1, 0x1D, 0x9E, + 0xE1, 0xF8, 0x98, 0x11, 0x69, 0xD9, 0x8E, 0x94, 0x9B, 0x1E, 0x87, 0xE9, 0xCE, 0x55, 0x28, 0xDF, + 0x8C, 0xA1, 0x89, 0x0D, 0xBF, 0xE6, 0x42, 0x68, 0x41, 0x99, 0x2D, 0x0F, 0xB0, 0x54, 0xBB, 0x16 +}; + +// 轮常数 +const array rcon = { + 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1B, 0x36 +}; + +using State = array, 4>; +using RoundKey = array; + +// 辅助函数:字节转字 +uint32_t bytes_to_word(const array& bytes) { + return (bytes[0] << 24) | (bytes[1] << 16) | (bytes[2] << 8) | bytes[3]; +} + +// 辅助函数:字转字节 +array word_to_bytes(uint32_t word) { + return { + static_cast(word >> 24), + static_cast((word >> 16) & 0xFF), + static_cast((word >> 8) & 0xFF), + static_cast(word & 0xFF) + }; +} + +// 密钥扩展 +vector key_expansion(const RoundKey& key) { + vector round_keys(11); + round_keys[0] = key; + + for (int i = 1; i <= 10; ++i) { + RoundKey new_key; + array temp; + + // 获取前一个密钥的最后4字节 + for (int j = 0; j < 4; ++j) + temp[j] = round_keys[i - 1][j + 12]; + + // RotWord + uint8_t tmp = temp[0]; + temp[0] = temp[1]; + temp[1] = temp[2]; + temp[2] = temp[3]; + temp[3] = tmp; + + // SubWord + for (int j = 0; j < 4; ++j) + temp[j] = s_box[temp[j]]; + + // 异或Rcon + temp[0] ^= rcon[i - 1]; + + // 生成新的轮密钥 + for (int j = 0; j < 4; ++j) + new_key[j] = round_keys[i - 1][j] ^ temp[j]; + + for (int j = 4; j < 16; ++j) + new_key[j] = new_key[j - 4] ^ round_keys[i - 1][j]; + + round_keys[i] = new_key; + } + return round_keys; +} + +// 字节替换 +void sub_bytes(State& state) { + for (auto& row : state) + for (auto& b : row) + b = s_box[b]; +} + +// 行移位 +void shift_rows(State& state) { + // 第1行左移1字节 + uint8_t temp = state[1][0]; + state[1][0] = state[1][1]; + state[1][1] = state[1][2]; + state[1][2] = state[1][3]; + state[1][3] = temp; + + // 第2行左移2字节 + swap(state[2][0], state[2][2]); + swap(state[2][1], state[2][3]); + + // 第3行左移3字节 + temp = state[3][3]; + state[3][3] = state[3][2]; + state[3][2] = state[3][1]; + state[3][1] = state[3][0]; + state[3][0] = temp; +} + +// 有限域乘法 +uint8_t gf_mult(uint8_t a, uint8_t b) { + uint8_t res = 0; + uint8_t hi_bit; + for (int i = 0; i < 8; ++i) { + if (b & 1) res ^= a; + hi_bit = a & 0x80; + a <<= 1; + if (hi_bit) a ^= 0x1B; // 模x^8 + x^4 + x^3 + x + 1 + b >>= 1; + } + return res; +} + +// 列混合 +void mix_columns(State& state) { + for (int col = 0; col < 4; ++col) { + uint8_t a = state[0][col]; + uint8_t b = state[1][col]; + uint8_t c = state[2][col]; + uint8_t d = state[3][col]; + + state[0][col] = gf_mult(a, 0x02) ^ gf_mult(b, 0x03) ^ c ^ d; + state[1][col] = a ^ gf_mult(b, 0x02) ^ gf_mult(c, 0x03) ^ d; + state[2][col] = a ^ b ^ gf_mult(c, 0x02) ^ gf_mult(d, 0x03); + state[3][col] = gf_mult(a, 0x03) ^ b ^ c ^ gf_mult(d, 0x02); + } +} + +// 轮密钥加 +void add_round_key(State& state, const RoundKey& key) { + for (int i = 0; i < 4; ++i) + for (int j = 0; j < 4; ++j) + state[i][j] ^= key[i + 4 * j]; +} + +// PKCS7填充 +vector pkcs7_pad(const vector& data) { + size_t pad_len = 16 - (data.size() % 16); + vector padded(data); + padded.insert(padded.end(), pad_len, static_cast(pad_len)); + return padded; +} + +// AES加密主函数 +vector aes_encrypt(const vector& plaintext, const RoundKey& key) { + auto round_keys = key_expansion(key); + vector ciphertext; + + for (size_t i = 0; i < plaintext.size(); i += 16) { + State state; + // 初始化状态矩阵 + for (int row = 0; row < 4; ++row) + for (int col = 0; col < 4; ++col) + state[row][col] = plaintext[i + row + 4 * col]; + + // 初始轮密钥加 + add_round_key(state, round_keys[0]); + + // 10轮加密 + for (int round = 1; round <= 10; ++round) { + sub_bytes(state); + shift_rows(state); + if (round != 10) mix_columns(state); + add_round_key(state, round_keys[round]); + } + + // 写入密文 + for (int row = 0; row < 4; ++row) + for (int col = 0; col < 4; ++col) + ciphertext.push_back(state[row][col]); + } + return ciphertext; +} +// 逆S盒 +const array inv_s_box = { + 0x52, 0x09, 0x6A, 0xD5, 0x30, 0x36, 0xA5, 0x38, 0xBF, 0x40, 0xA3, 0x9E, 0x81, 0xF3, 0xD7, 0xFB, + 0x7C, 0xE3, 0x39, 0x82, 0x9B, 0x2F, 0xFF, 0x87, 0x34, 0x8E, 0x43, 0x44, 0xC4, 0xDE, 0xE9, 0xCB, + 0x54, 0x7B, 0x94, 0x32, 0xA6, 0xC2, 0x23, 0x3D, 0xEE, 0x4C, 0x95, 0x0B, 0x42, 0xFA, 0xC3, 0x4E, + 0x08, 0x2E, 0xA1, 0x66, 0x28, 0xD9, 0x24, 0xB2, 0x76, 0x5B, 0xA2, 0x49, 0x6D, 0x8B, 0xD1, 0x25, + 0x72, 0xF8, 0xF6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xD4, 0xA4, 0x5C, 0xCC, 0x5D, 0x65, 0xB6, 0x92, + 0x6C, 0x70, 0x48, 0x50, 0xFD, 0xED, 0xB9, 0xDA, 0x5E, 0x15, 0x46, 0x57, 0xA7, 0x8D, 0x9D, 0x84, + 0x90, 0xD8, 0xAB, 0x00, 0x8C, 0xBC, 0xD3, 0x0A, 0xF7, 0xE4, 0x58, 0x05, 0xB8, 0xB3, 0x45, 0x06, + 0xD0, 0x2C, 0x1E, 0x8F, 0xCA, 0x3F, 0x0F, 0x02, 0xC1, 0xAF, 0xBD, 0x03, 0x01, 0x13, 0x8A, 0x6B, + 0x3A, 0x91, 0x11, 0x41, 0x4F, 0x67, 0xDC, 0xEA, 0x97, 0xF2, 0xCF, 0xCE, 0xF0, 0xB4, 0xE6, 0x73, + 0x96, 0xAC, 0x74, 0x22, 0xE7, 0xAD, 0x35, 0x85, 0xE2, 0xF9, 0x37, 0xE8, 0x1C, 0x75, 0xDF, 0x6E, + 0x47, 0xF1, 0x1A, 0x71, 0x1D, 0x29, 0xC5, 0x89, 0x6F, 0xB7, 0x62, 0x0E, 0xAA, 0x18, 0xBE, 0x1B, + 0xFC, 0x56, 0x3E, 0x4B, 0xC6, 0xD2, 0x79, 0x20, 0x9A, 0xDB, 0xC0, 0xFE, 0x78, 0xCD, 0x5A, 0xF4, + 0x1F, 0xDD, 0xA8, 0x33, 0x88, 0x07, 0xC7, 0x31, 0xB1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xEC, 0x5F, + 0x60, 0x51, 0x7F, 0xA9, 0x19, 0xB5, 0x4A, 0x0D, 0x2D, 0xE5, 0x7A, 0x9F, 0x93, 0xC9, 0x9C, 0xEF, + 0xA0, 0xE0, 0x3B, 0x4D, 0xAE, 0x2A, 0xF5, 0xB0, 0xC8, 0xEB, 0xBB, 0x3C, 0x83, 0x53, 0x99, 0x61, + 0x17, 0x2B, 0x04, 0x7E, 0xBA, 0x77, 0xD6, 0x26, 0xE1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0C, 0x7D +}; + +// 逆字节替换 +void inv_sub_bytes(State& state) { + for (auto& row : state) + for (auto& b : row) + b = inv_s_box[b]; +} + +// 逆行移位 +void inv_shift_rows(State& state) { + // 第1行右移1字节 + uint8_t temp = state[1][3]; + state[1][3] = state[1][2]; + state[1][2] = state[1][1]; + state[1][1] = state[1][0]; + state[1][0] = temp; + + // 第2行右移2字节 + swap(state[2][0], state[2][2]); + swap(state[2][1], state[2][3]); + + // 第3行右移3字节 + temp = state[3][0]; + state[3][0] = state[3][1]; + state[3][1] = state[3][2]; + state[3][2] = state[3][3]; + state[3][3] = temp; +} + +// 逆列混合 +void inv_mix_columns(State& state) { + for (int col = 0; col < 4; ++col) { + uint8_t a = state[0][col]; + uint8_t b = state[1][col]; + uint8_t c = state[2][col]; + uint8_t d = state[3][col]; + + state[0][col] = gf_mult(a, 0x0e) ^ gf_mult(b, 0x0b) ^ gf_mult(c, 0x0d) ^ gf_mult(d, 0x09); + state[1][col] = gf_mult(a, 0x09) ^ gf_mult(b, 0x0e) ^ gf_mult(c, 0x0b) ^ gf_mult(d, 0x0d); + state[2][col] = gf_mult(a, 0x0d) ^ gf_mult(b, 0x09) ^ gf_mult(c, 0x0e) ^ gf_mult(d, 0x0b); + state[3][col] = gf_mult(a, 0x0b) ^ gf_mult(b, 0x0d) ^ gf_mult(c, 0x09) ^ gf_mult(d, 0x0e); + } +} + +// PKCS7去填充 +vector pkcs7_unpad(const vector& data) { + if (data.empty()) return data; + uint8_t pad_len = data.back(); + if (pad_len > 16 || pad_len == 0) return data; + for (size_t i = data.size() - pad_len; i < data.size(); ++i) + if (data[i] != pad_len) return data; + return vector(data.begin(), data.end() - pad_len); +} + +// AES解密主函数 +vector aes_decrypt(const vector& ciphertext, const RoundKey& key) { + auto round_keys = key_expansion(key); + vector plaintext; + + for (size_t i = 0; i < ciphertext.size(); i += 16) { + State state; + // 初始化状态矩阵 + for (int row = 0; row < 4; ++row) + for (int col = 0; col < 4; ++col) + state[row][col] = ciphertext[i + row + 4 * col]; + + // 初始轮密钥加(使用最后一个轮密钥) + add_round_key(state, round_keys[10]); + + // 10轮解密 + for (int round = 9; round >= 0; --round) { + inv_shift_rows(state); + inv_sub_bytes(state); + add_round_key(state, round_keys[round]); + if (round > 0) inv_mix_columns(state); + } + + // 写入明文 + for (int row = 0; row < 4; ++row) + for (int col = 0; col < 4; ++col) + plaintext.push_back(state[row][col]); + } + + // 去除填充 + return pkcs7_unpad(plaintext); +} + +// 用户交互界面 +void user_interface() { + RoundKey key = { + 0x2b, 0x7e, 0x15, 0x16, 0x28, 0xae, 0xd2, 0xa6, + 0xab, 0xf7, 0x15, 0x88, 0x09, 0xcf, 0x4f, 0x3c + }; + + while (true) { + cout << "\n=== AES-128 加解密系统 ===" + << "\n1. 加密" + << "\n2. 解密" + << "\n0. 退出" + << "\n请选择操作:"; + + int choice; + cin >> choice; + cin.ignore(); // 清除输入缓冲 + + if (choice == 0) break; + + string input; + vector data; + + switch (choice) { + case 1: { + cout << "请输入要加密的明文:"; + getline(cin, input); + data = vector(input.begin(), input.end()); + data = pkcs7_pad(data); + + auto cipher = aes_encrypt(data, key); + cout << "\n加密结果(HEX):"; + for (auto b : cipher) printf("%02x", b); + cout << endl; + break; + } + case 2: { + cout << "请输入要解密的密文(HEX):"; + getline(cin, input); + + // 转换HEX字符串到字节流 + data.clear(); + for (size_t i = 0; i < input.length(); i += 2) { + string byte = input.substr(i, 2); + data.push_back(static_cast(stoul(byte, nullptr, 16))); + } + + auto plain = aes_decrypt(data, key); + cout << "\n解密结果:"; + for (auto b : plain) cout << static_cast(b); + cout << endl; + break; + } + default: + cout << "无效选择!" << endl; + } + } +} + +int main() { + user_interface(); + return 0; +} \ No newline at end of file