Cloud based re encryption. this uses el gamal re encryption procedure which uses a manager as intermediate between the owner of the file and the receiver of the file. File is send using java socket prgmg.

利用阿里云对象存储服务的云端加密API实现对用户上传文件的加密存储，实现云服务商端的数据加密保护。-Ali cloud object storage service utilizing cloud encryption API for users to upload files to achieve encrypted storage, data encryption protection cloud service provider side.