#分组长度为16个字节，加密10轮 #AES-128 import copy import os # 密钥扩展 def gen_key(key): key_bytes = key.encode('utf-8') if len(key_bytes) != 16: raise ValueError("Key must be 16 bytes after UTF-8 encoding.") key_hex = [hex(b) for b in key_bytes] key_rotate = [] w = [[] for i in range(0, 44)] for i in range(0, 16): w[i // 4].append(key_hex[i]) for i in range(4, 44): gw = copy.deepcopy(w[i - 1]) if i % 4 == 0: gw[0], gw[1], gw[2], gw[3] = gw[1], gw[2], gw[3], gw[0] gw = substitute(gw) #g(w(i-1)) gw[0] = hex(int(gw[0], 16) ^ rcon[i // 4 - 1]) for j in range(0, 4): w[i].append(hex(int(gw[j], 16) ^ int(w[i-4][j], 16))) key_rotate = [w[i * 4] + w[i * 4 + 1] + w[i * 4 + 2] + w[ i* 4 + 3] for i in range(0, 11)] # 轮密钥列表,每个元素都是有16个字节的列表 return key_rotate # 两个多项式相乘 def mul(poly1, poly2): result = 0 for index in range(poly2.bit_length()): if poly2 & (1 << index): result ^= (poly1 << index) return result # 多项式poly模多项式100011011 def mod(poly, mod = 0b100011011): while poly.bit_length() > 8: poly ^= (mod << (poly.bit_length() - 9)) return poly #对输入的十六进制列表 m_hex 进行字节代换操作。 def substitute(m_hex, inverse=False): m_s = [] box = s_box if not inverse else i_s_box for i in m_hex: x, y = int(i, 16) // 16, int(i, 16) % 16 temp = hex(box[x*16+y]) m_s.append(temp) return m_s 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] i_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] rcon = [0x1, 0x2, 0x4, 0x8, 0x10, 0x20, 0x40, 0x80, 0x1B, 0x36] def xor(a, key): return [hex(int(ai, 16) ^ int(ki, 16)) for ai, ki in zip(a, key)] # 行移位 def shiftrows(a, inverse=False): #inverse为True时表示为逆操作，默认为False if not inverse: return [ a[0], a[5], a[10], a[15], a[4], a[9], a[14], a[3], a[8], a[13], a[2], a[7], a[12], a[1], a[6], a[11] ] else : return[ a[0], a[13], a[10], a[7], a[4], a[1], a[14], a[11], a[8], a[5], a[2], a[15], a[12], a[9], a[6], a[3] ] # 列混淆 def mixcolumn(m_row, inverse=False): matrix = mix_column_matrix if not inverse else i_mix_column_matrix m_col = [] for i in range(0, 16): x, y = i % 4, i // 4 result = 0 for j in range(0, 4): result ^= (mul(matrix[x * 4 + j], int(m_row[y * 4 + j], 16))) result = mod(result) m_col.append(hex(result)) return m_col # 列混合乘的矩阵 mix_column_matrix = [0x2, 0x3, 0x1, 0x1, 0x1, 0x2, 0x3, 0x1, 0x1, 0x1, 0x2, 0x3, 0x3, 0x1, 0x1, 0x2] # 列混合乘的逆矩阵 i_mix_column_matrix = [0xe, 0xb, 0xd, 0x9, 0x9, 0xe, 0xb, 0xd, 0xd, 0x9, 0xe, 0xb, 0xb, 0xd, 0x9, 0xe] def aes_encrypt_block(block, key_rotate): state = block state = xor(state, key_rotate[0]) for rnd in range(1, 10): state = substitute(state) state = shiftrows(state) state = mixcolumn(state) state = xor(state, key_rotate[rnd]) state = substitute(state) state = shiftrows(state) state = xor(state, key_rotate[10]) return [int(b, 16) for b in state] def aes_decrypt_block(block, key_rotate): state = block state = xor(state, key_rotate[10]) state = shiftrows(state, inverse=True) state = substitute(state, inverse=True) for rnd in range(9, 0, -1): state = xor(state, key_rotate[rnd]) state = mixcolumn(state, inverse=True) state = shiftrows(state, inverse=True) state = substitute(state, inverse=True) state = xor(state, key_rotate[0]) return [int(b, 16) for b in state] def pad(data): pad_len = 16 - (len(data) % 16) return data + bytes([pad_len] * pad_len) def unpad(data): pad_len = data[-1] return data[:-pad_len] def aes_cbc_encrypt(plaintext, key): key_rotate = gen_key(key) iv = os.urandom(16) print(f"\n[生成随机IV] (16字节): {iv.hex()}") plaintext = pad(plaintext.encode()) blocks = [plaintext[i:i+16] for i in range(0, len(plaintext), 16)] ciphertext = iv prev = iv for block in blocks: block = bytes([b ^ p for b, p in zip(block, prev)]) encrypted = aes_encrypt_block([hex(b)[2:].zfill(2) for b in block], key_rotate) encrypted_bytes = bytes(encrypted) ciphertext += encrypted_bytes prev = encrypted_bytes return ciphertext.hex() def aes_cbc_decrypt(ciphertext, key): key_rotate = gen_key(key) ciphertext = bytes.fromhex(ciphertext) iv = ciphertext[:16] blocks = [ciphertext[i:i+16] for i in range(16, len(ciphertext), 16)] plaintext = b'' prev = iv for block in blocks: decrypted = aes_decrypt_block([hex(b)[2:].zfill(2) for b in block], key_rotate) decrypted = bytes([d ^ p for d, p in zip(decrypted, prev)]) plaintext += decrypted prev = block return unpad(plaintext).decode() if __name__ == '__main__': mode = input("请输入模式 (encrypt/decrypt): ").strip().lower() key = input("请输入16字节密钥: ").strip() if len(key.encode('utf-8')) != 16: print("错误：密钥长度必须为16字节！") else: if mode == "encrypt": plaintext = input("请输入明文: ").strip() print("加密后密文:", aes_cbc_encrypt(plaintext, key)) elif mode == "decrypt": ciphertext = input("请输入密文 (16进制字符串): ").strip() try: print("解密后明文:", aes_cbc_decrypt(ciphertext, key)) except Exception as e: print(f"解密失败: {e}") else: print("无效模式，请输入 encrypt 或 decrypt")