实验二

流密码主要算法实现

姓名：徐慧聪

学号：2023103793

1. 实验环境

  • ubuntu 22.04
  • Python 3.10
  • 文件结构（/dist/StreamCipher为可执行文件）

Untitled

2. 代码实现

2.1 Grain

  • LFSR存key
  • NFSR存全1
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class Grain128:
    def __init__(self, key):
        self.LFSR = key & 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
        self.NFSR = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF

    def clock(self):
        feedback_LFSR = (self.LFSR >> 7) & 1 ^ (self.LFSR >> 38) & 1 ^ (self.LFSR >> 70) & 1 ^ (self.LFSR >> 81) & 1 ^ (self.LFSR >> 96) & 1
        feedback_NFSR = self.LFSR & 1 ^ (self.NFSR >> 26) & 1 ^ (self.NFSR >> 56) & 1 ^ (self.NFSR >> 91) & 1 ^ (self.NFSR >> 96) & 1 ^ (self.NFSR >> 3) & (self.NFSR >> 67) & 1 ^ (self.NFSR >> 11) & (self.NFSR >> 13) & 1 ^ (self.NFSR >> 17) & (self.NFSR >> 18) & 1 ^ (self.NFSR >> 27) & (self.NFSR >> 59) & 1 ^ (self.NFSR >> 40) & (self.NFSR >> 48) & 1 ^ (self.NFSR >> 61) & (self.NFSR >> 65) & 1 ^ (self.NFSR >> 68) & (self.NFSR >> 84) & 1 ^ (self.NFSR >> 88) & (self.NFSR >> 92) & (self.NFSR >> 93) & (self.NFSR >> 95) & 1 ^ (self.NFSR >> 22) & (self.NFSR >> 24) & (self.NFSR >> 25) & 1 ^ (self.NFSR >> 70) & (self.NFSR >> 78) & (self.NFSR >> 82) & 1

        self.NFSR >>= 1
        self.NFSR |= feedback_LFSR << 127
        self.LFSR >>= 1
        self.LFSR |= feedback_NFSR << 127

        return feedback_LFSR, feedback_NFSR

    def h(self, s, b):
        return (b >> 12) & 1 ^ (s >> 8) & 1 ^ (s >> 13) & (s >> 20) & 1 ^ (b >> 95) & (s >> 42) & 1 ^ (s >> 60) & (s >> 79) & 1 ^ (b >> 12) & (b >> 95) & (s >> 94) & 1

    def generate_keystream(self, length):
        keystream = []
        for _ in range(length):
            feedback_LFSR, feedback_NFSR = self.clock()
            keystream.append(self.h(self.NFSR, self.LFSR))
        return keystream

    def encrypt(self, plaintext):
        keystream = self.generate_keystream(len(plaintext))
        ciphertext = bytes([plaintext[i] ^ keystream[i] for i in range(len(plaintext))])
        return ciphertext

    def decrypt(self, ciphertext):
        return self.encrypt(ciphertext)  # XOR 加密和解密是相同的操作

2.2 Trivium

  • 与Grain算法类似
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class Trivium:
    def __init__(self, key, iv):
        self.state = [0] * 288
        
        # 将密钥和初始向量放入寄存器
        for i in range(80):
            self.state[i] = (key >> i) & 1
        for i in range(94, 177):
            self.state[i] = (iv >> (i - 94)) & 1
        for i in range(285, 288):
            self.state[i] = 1

    def clock(self):
        t1 = self.state[65] ^ self.state[92]
        t2 = self.state[161] ^ self.state[176]
        t3 = self.state[242] ^ self.state[287]

        z = t1 ^ t2 ^ t3

        t1 ^= self.state[90] & self.state[91] ^ self.state[170]
        t2 ^= self.state[174] & self.state[175] ^ self.state[263]
        t3 ^= self.state[285] & self.state[286] ^ self.state[68]

        self.state = [t3] + self.state[:92] + [t1] + self.state[93:176] + [t2] + self.state[177:287]
        # print(len(self.state))
        return z
    
    def generate_keystream(self, length):
        keystream = []
        for _ in range(length):
            z = self.clock()
            keystream.append(z)
        return keystream
        
    def encrypt(self, plaintext):
        keystream = self.generate_keystream(len(plaintext))
        ciphertext = bytes([plaintext[i] ^ keystream[i] for i in range(len(plaintext))])
        return ciphertext

    def decrypt(self, ciphertext):
        return self.encrypt(ciphertext)  # XOR 加密和解密是相同的操作

2.3 ZUC

  • 加载密钥
  • LFSR状态重组
  • 计算非线性函数F
  • LFSR的初始化模式和工作模式
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class ZUC_128:
    def __init__(self, key, iv, D):
        self.key = key # 128位密钥
        self.iv = iv # 128位初始化向量
        self.D = D # 240位常量
        
        self.LFSR = [0]*16 # 31bit*16寄存器单元
        self.R1 = 0 # 2个32bit记忆单元
        self.R2 = 0
        self.BRx = [0]*4 # 比特重组后的结果
        self.init_zuc()
    
    def load_key(self):
        # 将key ,iv,D重组为31bit*16LFSR
        # 将key,iv 分为8bit * 16个单元
        key_units = [(self.key >> (15 - i) * 8) & 0xFF for i in range(16)]
        iv_units = [(self.iv >> (15 - i) * 8) & 0xFF for i in range(16)]
        
        # 将D 分为15位16个单元
        D_units = [(self.D >> (15 - i) * 15) & 0x7FFF for i in range(16)]

        # 将8+8+15组成新的整数存入LFSR中
        for i in range(16):
            self.LFSR[i] = (key_units[i] << 23) | (iv_units[i] << 15) | D_units[i]
    
    def BR(self):
        # 将LFSR状态重组，生成四个X变量
        self.BRx[0] = ((self.LFSR[15] & 0x7fff8000) << 1) | (self.LFSR[14] & 0xffff)
        self.BRx[1] = ((self.LFSR[11] & 0xFFFF) << 16) | ((self.LFSR[9] >> 15) & 0x7fff)
        self.BRx[2] = ((self.LFSR[7] & 0xFFFF) << 16) | ((self.LFSR[5] >> 15) & 0x7fff)
        self.BRx[3] = ((self.LFSR[2] & 0xFFFF) << 16) | ((self.LFSR[0] >> 15) & 0x7fff)
    
    def L1(self, X):
        # 计算线性函数L1
        return X ^ (X << 2) ^ (X << 10) ^ (X << 18) ^ (X << 24)
    
    def L2(self, X):
        # 计算线性函数L2
        return X ^ (X << 8) ^ (X << 14) ^ (X << 22) ^ (X << 30)
    
    def S(self, X):
        # 定义S函数，这里假设您已经有了四个8x8的S盒
        S_boxes = [
            # S0
            [
                [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]
            ],
            # S1
            [
                [0x51, 0xF4, 0xA7, 0x50, 0x68, 0x6B, 0x8A, 0x42, 0xDB, 0x32, 0xF0, 0xFD, 0x66, 0x03, 0x91, 0x26],
                [0x37, 0x6E, 0xD8, 0xCB, 0x1E, 0x09, 0x2C, 0x8F, 0xB5, 0x18, 0x89, 0x14, 0xF3, 0x9A, 0xF5, 0xE9],
                [0xC9, 0x4E, 0xD7, 0xE3, 0x5D, 0x50, 0x26, 0x3B, 0x04, 0xB8, 0xA5, 0xE8, 0x0A, 0x56, 0x8D, 0xE7],
                [0x60, 0xFC, 0xB1, 0xCC, 0x23, 0x3D, 0x36, 0x0F, 0x6F, 0x7D, 0x9B, 0x9E, 0x95, 0x10, 0x78, 0xA9],
                [0x7C, 0xD0, 0xF2, 0x6A, 0x3F, 0x1C, 0x71, 0x4B, 0xAD, 0x4D, 0x0D, 0x22, 0x2A, 0x90, 0x88, 0x46],
                [0xEE, 0xB8, 0x14, 0xDE, 0x5E, 0x0B, 0xDB, 0xE0, 0x32, 0x3A, 0x0A, 0x49, 0x06, 0x24, 0x5C, 0xC2],
                [0x49, 0x06, 0x24, 0x5C, 0xC2, 0xD3, 0xAC, 0x62, 0x91, 0x95, 0xE4, 0x79, 0xE7, 0xC8, 0x37, 0x6D],
                [0xB3, 0x8E, 0x67, 0x32, 0xCA, 0x4A, 0x1C, 0xA9, 0x7C, 0x03, 0xB7, 0x7B, 0x2A, 0x11, 0x99, 0x47],
                [0x70, 0x3E, 0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E, 0x61, 0x35, 0x57, 0xB9, 0x86, 0xC1, 0x1D, 0x9E],
                [0xC4, 0xF2, 0xD0, 0x46, 0x71, 0x1D, 0x18, 0xDB, 0x52, 0x9E, 0xE3, 0xB6, 0x36, 0x87, 0x0E, 0x95],
                [0x37, 0x6E, 0xD8, 0xCB, 0x1E, 0x09, 0x2C, 0x8F, 0xB5, 0x18, 0x89, 0x14, 0xF3, 0x9A, 0xF5, 0xE9],
                [0x5E, 0xFA, 0x64, 0xCB, 0xB4, 0x97, 0xBE, 0x2B, 0xBC, 0x77, 0x2E, 0x03, 0xD3, 0x19, 0x59, 0xCF],
                [0xBA, 0x78, 0x25, 0x2E, 0x1C, 0xA6, 0xB4, 0xC6, 0xE8, 0xDD, 0x74, 0x1F, 0x4B, 0xBD, 0x8B, 0x8A],
                [0x74, 0x1F, 0x4B, 0xBD, 0x8B, 0x8A, 0x70, 0x3E, 0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E, 0x61, 0x35],
                [0x02, 0x7F, 0x50, 0x3C, 0x9F, 0xA8, 0x7C, 0x80, 0x9F, 0x5D, 0x9D, 0x43, 0x59, 0xF9, 0xB9, 0x34],
                [0x59, 0xCF, 0x36, 0x09, 0x7D, 0xB8, 0x1E, 0x8F, 0x12, 0x4B, 0xDE, 0x6C, 0x91, 0x9B, 0x8D, 0x92]
            ],
            # S2
            [
                [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]
            ],
            # S3
            [
                [0x51, 0xF4, 0xA7, 0x50, 0x68, 0x6B, 0x8A, 0x42, 0xDB, 0x32, 0xF0, 0xFD, 0x66, 0x03, 0x91, 0x26],
                [0x37, 0x6E, 0xD8, 0xCB, 0x1E, 0x09, 0x2C, 0x8F, 0xB5, 0x18, 0x89, 0x14, 0xF3, 0x9A, 0xF5, 0xE9],
                [0xC9, 0x4E, 0xD7, 0xE3, 0x5D, 0x50, 0x26, 0x3B, 0x04, 0xB8, 0xA5, 0xE8, 0x0A, 0x56, 0x8D, 0xE7],
                [0x60, 0xFC, 0xB1, 0xCC, 0x23, 0x3D, 0x36, 0x0F, 0x6F, 0x7D, 0x9B, 0x9E, 0x95, 0x10, 0x78, 0xA9],
                [0x7C, 0xD0, 0xF2, 0x6A, 0x3F, 0x1C, 0x71, 0x4B, 0xAD, 0x4D, 0x0D, 0x22, 0x2A, 0x90, 0x88, 0x46],
                [0xEE, 0xB8, 0x14, 0xDE, 0x5E, 0x0B, 0xDB, 0xE0, 0x32, 0x3A, 0x0A, 0x49, 0x06, 0x24, 0x5C, 0xC2],
                [0x49, 0x06, 0x24, 0x5C, 0xC2, 0xD3, 0xAC, 0x62, 0x91, 0x95, 0xE4, 0x79, 0xE7, 0xC8, 0x37, 0x6D],
                [0xB3, 0x8E, 0x67, 0x32, 0xCA, 0x4A, 0x1C, 0xA9, 0x7C, 0x03, 0xB7, 0x7B, 0x2A, 0x11, 0x99, 0x47],
                [0x70, 0x3E, 0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E, 0x61, 0x35, 0x57, 0xB9, 0x86, 0xC1, 0x1D, 0x9E],
                [0xC4, 0xF2, 0xD0, 0x46, 0x71, 0x1D, 0x18, 0xDB, 0x52, 0x9E, 0xE3, 0xB6, 0x36, 0x87, 0x0E, 0x95],
                [0x37, 0x6E, 0xD8, 0xCB, 0x1E, 0x09, 0x2C, 0x8F, 0xB5, 0x18, 0x89, 0x14, 0xF3, 0x9A, 0xF5, 0xE9],
                [0x5E, 0xFA, 0x64, 0xCB, 0xB4, 0x97, 0xBE, 0x2B, 0xBC, 0x77, 0x2E, 0x03, 0xD3, 0x19, 0x59, 0xCF],
                [0xBA, 0x78, 0x25, 0x2E, 0x1C, 0xA6, 0xB4, 0xC6, 0xE8, 0xDD, 0x74, 0x1F, 0x4B, 0xBD, 0x8B, 0x8A],
                [0x74, 0x1F, 0x4B, 0xBD, 0x8B, 0x8A, 0x70, 0x3E, 0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E, 0x61, 0x35],
                [0x02, 0x7F, 0x50, 0x3C, 0x9F, 0xA8, 0x7C, 0x80, 0x9F, 0x5D, 0x9D, 0x43, 0x59, 0xF9, 0xB9, 0x34],
                [0x59, 0xCF, 0x36, 0x09, 0x7D, 0xB8, 0x1E, 0x8F, 0x12, 0x4B, 0xDE, 0x6C, 0x91, 0x9B, 0x8D, 0x92]
            ]
        ]
        
        S = lambda i, x: S_boxes[i][x >> 4][x & 0xF]
        x0 = (X >> 24) & 0xFF
        x1 = (X >> 16) & 0xFF
        x2 = (X >> 8) & 0xFF
        x3 = X & 0xFF
        y = (S(0,x0) << 24) | (S(1,x1) << 16) | (S(2,x2) << 8) | S(3,x3)
        return y
    
    def F(self):
        # 计算非线性F函数
        self.BR()
        w = ((self.BRx[0] ^ self.R1) + self.R2 ) & 0xFFFFFFFF
        W1 = (self.R1 + self.BRx[1]) & 0xFFFFFFFF
        W2 = self.R2 ^ self.BRx[2]
        self.R1 = self.S(self.L1((W1 << 16) | (W2 >> 16)));
        self.R2 = self.S(self.L2((W2 << 16) | (W1 >> 16)));
        return w
        
    def LFSRWithInitMode(self,u):
        v = 0
        tmp = 0

        v = self.LFSR[0]
        tmp = mod_2exp_mul(self.LFSR[0], 8)
        v = mod_add(v, tmp)

        tmp = mod_2exp_mul(self.LFSR[4], 20)
        v = mod_add(v, tmp)

        tmp = mod_2exp_mul(self.LFSR[10], 21)
        v = mod_add(v, tmp)

        tmp = mod_2exp_mul(self.LFSR[13], 17)
        v = mod_add(v, tmp)

        tmp = mod_2exp_mul(self.LFSR[15], 15)
        v = mod_add(v, tmp)

        v = mod_add(v, u)
        if v == 0:
            v = 0x7fffffff

        self.LFSR = self.LFSR[1:] + [v]
    
    def LFSRWithWorkMode(self):
        v = 0
        tmp = 0

        v = self.LFSR[0]
        tmp = mod_2exp_mul(self.LFSR[0], 8)
        v = mod_add(v, tmp)

        tmp = mod_2exp_mul(self.LFSR[4], 20)
        v = mod_add(v, tmp)

        tmp = mod_2exp_mul(self.LFSR[10], 21)
        v = mod_add(v, tmp)

        tmp = mod_2exp_mul(self.LFSR[13], 17)
        v = mod_add(v, tmp)

        tmp = mod_2exp_mul(self.LFSR[15], 15)
        v = mod_add(v, tmp)

        if v == 0:
            v = 0x7fffffff

        self.LFSR = self.LFSR[1:] + [v]
    
    def init_zuc(self):
        self.load_key()
        self.R1 = 0
        self.R2 = 0
        for i in range(32):
            self.BR()
            w = self.F()
            self.LFSRWithInitMode(w>>1)

    def clock(self):
        self.BR()
        w = self.F()
        z = w ^ self.BRx[3]
        self.LFSRWithWorkMode()
        return z
    
    def generate_keystream(self, length):
        keystream = []
        self.BR()
        self.F()
        self.LFSRWithWorkMode()
        for _ in range(length):
            z = self.clock()
            # print(z)
            keystream.extend(z.to_bytes(4, byteorder='big'))
        return keystream

    def encrypt(self, plaintext):
        keystream = self.generate_keystream(len(plaintext))
        # print(len(plaintext))
        ciphertext = bytes([plaintext[i] ^ keystream[i] for i in range(len(plaintext))])
        return ciphertext

    def decrypt(self, ciphertext):
        return self.encrypt(ciphertext)  # XOR 加密和解密是相同的操作

3. 实验

3.1 main

  • 根据输入参数，选择加密算法
  • 根据输入参数，选择终端读入还是文件读入
    • 输入-：终端读入
    • 输入文件名：文件读入
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def main():
    if len(sys.argv) < 2:
        print("Usage: python cipher.py <algorithm> <input>")
        print("Supported algorithms: Grain, Trivium, ZUC")
        return

    algorithm = sys.argv[1].lower()
    input_file = sys.argv[2]

    if algorithm == "grain":
        key = 0x01234567  # 128 位密钥
        encryption = Grain128(key)
        decryption = Grain128(key)
    elif algorithm == "trivium":
        key = 0x01234
        iv = 0xabcde
        encryption = Trivium(key, iv)
        decryption = Trivium(key, iv)
    elif algorithm == "zuc":
        key = 0x01234567
        iv = 0x89abcdef
        D = 0x0123456789abcdef
        encryption = ZUC_128(key, iv,D)
        decryption = ZUC_128(key, iv,D)
    else:
        print("Unknown algorithm:", algorithm)
        return

    # 从终端输入读取
    if input_file == "-":
        plaintext = input("Enter plaintext: ")
        plaintext_bytes = plaintext.encode()
        ciphertext = encryption.encrypt(plaintext_bytes)
        print("Ciphertext:", ciphertext)

    # 从文件输入读取
    else:
        with open(input_file, "rb") as file:
            plaintext_bytes = file.read()
        ciphertext = encryption.encrypt(plaintext_bytes)
        with open("encrypted_output.bin", "wb") as file:
            print("Ciphertext:", ciphertext)
            file.write(ciphertext)
        print("Encryption complete. Output saved to encrypted_output.bin")

    # 解密
    decrypted_text = decryption.decrypt(ciphertext)
    print("Decrypted text:", decrypted_text.decode())

3.2 实验结果

  • Grain

Untitled

  • Trivium

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  • Zuc

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总结

  • 使用Python实现三类加密方法
  • 支持文件读入和终端读入
  • 利用PyInstaller实现Python文件打包成可执行文件