python基于crypto实现加密与解密

1.安装crypto库

pip install pycryptodome

ps：
使用pip工具安装步骤：
1、直接安装pycryptodome模块即可
pip install pycryptodome
2、如果你已经通过pip install crypto命令安装了，那么需要做以下两步：
（1）切换到python安装目录的liib\site-packages目录下，将crypto目录名称修改为Crypto,即将首字母小写改成大写。
（2）安装pycryptodome，使用命令pip install pycryptodome。安装pycryptodome后Crypto目录会多出很多实际程序要用到的文件目录。

2.实现AES的加密解密

from Crypto.Cipher import AESfrom Crypto.Util.Padding import pad, unpadfrom Crypto.Random import get_random_bytesdef encrypt(plain_text, key):    iv = get_random_bytes(AES.block_size)    cipher = AES.new(key, AES.MODE_CBC, iv)    cipher_text = cipher.encrypt(pad(plain_text, AES.block_size))    return iv + cipher_textdef decrypt(cipher_text, key):    iv = cipher_text[:AES.block_size]    cipher = AES.new(key, AES.MODE_CBC, iv)    plain_text = unpad(cipher.decrypt(cipher_text[AES.block_size:]), AES.block_size)    return plain_texTKEy = get_random_bytes(16)  # 16字节（128位）的随机密钥plain_text = b'hello world'cipher_text = encrypt(plain_text, key)decrypted_text = decrypt(cipher_text, key)print('Plain text:', plain_text)print('Decrypted text:', decrypted_text)

不过要注意的是，在PyCharm使用需要注意，直接import Crypto会报错，因为安装后再文件夹内的文件名是crypto，全是小写，而我们直接import crypto也是会出错，需要我们手动修改库文件名字为Crypto,参考文章：
https://blog.csdn.net/weixin_44133008/article/details/107102575

3.实现3DES加密解密

from Crypto.Cipher import DES3from Crypto.Util.Padding import pad, unpad# 加密函数def encrypt(key, plaintext):    # 创建3DES加密器    cipher = DES3.new(key, DES3.MODE_ECB)    # 填充明文    plaintext = pad(plaintext, DES3.block_size)    # 加密明文    ciphertext = cipher.encrypt(plaintext)    return ciphertext# 解密函数def decrypt(key, ciphertext):    # 创建3DES解密器    cipher = DES3.new(key, DES3.MODE_ECB)    # 解密密文    plaintext = cipher.decrypt(ciphertext)    # 去除填充    plaintext = unpad(plaintext, DES3.block_size)    return plaintext# 示例用法key = b"0123456789abcdef"plaintext = b"Hello, world!"ciphertext = encrypt(key, plaintext)decrypted_plaintext = decrypt(key, ciphertext)print("明文：", plaintext)print("密文：", ciphertext)print("解密后明文：", decrypted_plaintext)

4.通过cryptography库实现3DES加密解密

其中需要指定加密方式为CBC，补码方式为PKCS7，不过以下代码解密后的内容有部分为乱码，有待解决。

from cryptography.hazmat.primitives.ciphers import Cipher, alGorithms, modesfrom cryptography.hazmat.backends import default_backendimport os# 3DES加密函数def des_3_encrypt(data, key):    # 创建3DES加密器    cipher = Cipher(algorithms.TripleDES(key), modes.CBC(os.urandom(8)), backend=default_backend())    # 加密数据    encryptor = cipher.encryptor()    padded_data = pad(data, 8, style='pkcs7')    encrypted_data = encryptor.update(padded_data) + encryptor.finalize()    return encrypted_data# 3DES解密函数def des_3_decrypt(data, key):    # 创建3DES解密器    cipher = Cipher(algorithms.TripleDES(key), modes.CBC(os.urandom(8)), backend=default_backend())    # 解密数据    decryptor = cipher.decryptor()    decrypted_data = decryptor.update(data) + decryptor.finalize()    unpadded_data = unpad(decrypted_data, 8, style='pkcs7')    return unpadded_data# PKCS7补码函数def pad(data, block_size, style='pkcs7'):    padding_size = block_size - len(data) % block_size    padding = bytes([padding_size] * padding_size)    if style == 'pkcs7':        return data + padding    elif style == 'x923':        return b'\x80' + data + padding    else:        raise ValueError('Invalid padding style')# PKCS7去码函数def unpad(data, block_size, style='pkcs7'):    if style == 'pkcs7':        padding_size = data[-1]    elif style == 'x923':        padding_size = data[-1]        if padding_size > block_size:            raise ValueError('Invalid padding')        if data[-padding_size:]!= bytes([padding_size] * padding_size):            raise ValueError('Invalid padding')    else:        raise ValueError('Invalid padding style')    return data[:-padding_size]key = b"0123456789abcdef"data = b"01234567890ABCDEF"encrypted_data = des_3_encrypt(data, key)decrypted_data = des_3_decrypt(encrypted_data, key)print("Original data:", data)print("Encrypted data:", encrypted_data)print("Decrypted data:", decrypted_data)print(decrypted_data.decode("ascii"))

来源地址：https://blog.csdn.net/LCY133/article/details/131801166