Question

我在python3中创建了这个软件。问题是如果我想要解密文件，我的软件不会写结果。我使用easygui作为gui的gui。最后，我没有任何错误消息。该软件通常关闭，但文件保持加密状态。

def decrypt(key, filename):
    chunksize = 64 * 1024
    outputFile = filename[11:]

    with open(filename, 'rb') as infile:
        filesize = int(infile.read(16))
        IV = infile.read(16)

        decryptor = AES.new(key, AES.MODE_CBC, IV)

        with open(outputFile, 'wb') as outfile:
            while True:
                chunk = infile.read(chunksize)

                if len(chunk) == 0:
                    break

                outfile.write(decryptor.decrypt(chunk))
            outfile.truncate(filesize)


def getKey(password):
    hasher = SHA256.new(password.encode('utf-8'))
    return hasher.digest()


def Main():
    image = "./images/encryption.gif"
    msg = "Do you want to encrypt or decrypt a file ?"
    choices = ["Encrypt", "Decrypt", "Exit"]
    reply = buttonbox(msg, image=image, choices=choices)


    if reply == 'Encrypt':
         filename = fileopenbox(msg="Select the file to Encrypt",title="Select the file to Encrypt", default='*', filetypes=None, multiple=False)
        password = passwordbox(msg="Enter a password",title="Enter a password",default="")
        encrypt(getKey(password),filename)

     elif reply == 'Decrypt':
        filename = fileopenbox(msg="Select the file to Decrypt", title="Select the file to Decrypt", default='*', filetypes=None, multiple=False)
        password = passwordbox(msg="Enter a password",title="Enter a password",default="")
        decrypt(getKey(password),filename)

    else:
        sys.exit(0)


 if __name__ == '__main__':
    Main()

Answer 1

您忘记考虑AESCipher.encrypt and AESCipher.decrypt的要求：您需要自己执行必要的填充：

对于MODE_ECB，MODE_CBC和MODE_OFB，明文长度（以字节为单位）必须是block_size的倍数。

如果由于消息的某些部分保留在缓存中而未提供正好是16字节的倍数的消息（文件内容），则可能会遗漏部分密文。因此，每次执行加密时，可能会从输入文件中删除0到15个字节。

显然，对于最多15个字节的非常小的文件，不会留下任何东西。

我可以用python 3中的pycrypto加密但不解密

1 个答案: