中文摘要：

为了解决目前文件安全方面存在的问题，进一步提高对文件数据的保护强度，对基于文件系统过滤驱动的文件透明加／解密技术进行了研究，针对传统方法在加密标识识别方面存在的不足，提出了文件头保存文件加密标识的方法。该方法通过过滤驱动为密文文件添加一个包含加密标识的文件头，在进行文件操作时通过该加密标识识别密文文件。同时过滤驱动在处理文件的读写操作时，通过设置文件读写偏移跳过文件头，完成正确的读写操作。结合实例，对测试结果进行了分析，验证了该设计的准确性、有效性和可行性。

英文摘要：

To resolve the problems in document security currently, improve the strength of the protection of file data further, the technology of file transparent encryption/decryption based on file system fiker driver is studied. Aiming at the problems of the traditional methods in encryption logo recognition, an idea of saving file encryption logo in file header is proposed. This idea is driven by the filter driver to add a ciphertext file header containing the encrypted identity, this idea can determine whether ci- phertext file by the eneryption identification during fi~.e operations. Whi~e the filter driver processes file read and write opera tions, the header is skpped by setting the file read and write offset to complete the correct read and write operations. With exam- ples, the test results are analyzed, the accuracy, validity and feasibility of the design is demonstrated.