This paper introduces Cit-cryptographic service provider ( Cit-CSP ) that is developed as a subsystem of the Cit / E-commerce security platform to provide strong key security services and cryptographic algorithms such as message digest, block cipher, cipher ( asymmetric ), signature and MAC functions. 介绍了Cit-CSP--Cit/E-commerce信息安全保障平台子系统,并阐述了它所提供的消息摘要、块加密、加密(公钥)、签名和MAC等功能和服务。