在Python中实现AES-256-CFB的加解密

from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives import padding
from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC

def encrypt(plaintext, password):
    # 生成随机的盐值
    salt = b'\x00' * 16

    # 使用PBKDF2算法生成密钥
    kdf = PBKDF2HMAC(
        algorithm=hashes.SHA256(),
        length=32,
        salt=salt,
        iterations=100000,
        backend=default_backend()
    )
    key = kdf.derive(password)

    # 生成随机的初始化向量
    iv = b'\x00' * 16

    # 使用AES-256-CFB模式进行加密
    cipher = Cipher(algorithms.AES(key), modes.CFB(iv), backend=default_backend())
    encryptor = cipher.encryptor()

    # 对明文进行填充
    padder = padding.PKCS7(128).padder()
    padded_plaintext = padder.update(plaintext) + padder.finalize()

    # 加密密文
    ciphertext = encryptor.update(padded_plaintext) + encryptor.finalize()

    return ciphertext

def decrypt(ciphertext, password):
    # 生成随机的盐值
    salt = b'\x00' * 16

    # 使用PBKDF2算法生成密钥
    kdf = PBKDF2HMAC(
        algorithm=hashes.SHA256(),
        length=32,
        salt=salt,
        iterations=100000,
        backend=default_backend()
    )
    key = kdf.derive(password)

    # 生成随机的初始化向量
    iv = b'\x00' * 16

    # 使用AES-256-CFB模式进行解密
    cipher = Cipher(algorithms.AES(key), modes.CFB(iv), backend=default_backend())
    decryptor = cipher.decryptor()

    # 解密密文
    padded_plaintext = decryptor.update(ciphertext) + decryptor.finalize()

    # 去除填充
    unpadder = padding.PKCS7(128).unpadder()
    plaintext = unpadder.update(padded_plaintext) + unpadder.finalize()

    return plaintext

# 示例用法
plaintext = b"Hello, world!"
password = b"mysecretpassword"

ciphertext = encrypt(plaintext, password)
decrypted_plaintext = decrypt(ciphertext, password)

print("明文:", plaintext)
print("加密后的密文:", ciphertext)
print("解密后的明文:", decrypted_plaintext)