无安全信道的OSBE方案

Oblivious signature-based envelope without secure channel

基于访问控制策略的协议无法解决信任协商中出现的循环依赖问题,OSBE(oblivious signature-based en-velope)方案可用来克服循环依赖,然而既有方案需要建立在一个安全信道上才能实施.利用基于身份的系统和基于证书加密的思想,提出一个高效率的不需要安全信道的OSBE方案,并证明了新方案不仅满足有效性、不经意性等OSBE的所有性质,而且也克服了原OSBE方案中接收者外传证书和签名的问题;在随机预言模型下,如果不存在一个多项式时间的算法能以不可忽略的概率伪造对消息的聚合签名,那么方案对接受者是安全的.

Exchange of digitally signed certificates was often used to establish mutual trust between strangers that wish to share resources or to conduct business transactions. Automated trust negotiation （ATN） was an approach to regulate the flow of sensitive information during such an exchange. But ATN cannot handle cyclic policy interdependency satisfactorily. Oblivious signature based envelope （OSBE） is a scheme to solve this problem. However, the existed scheme could only be implemented on a secure channel. An efficient OSBE scheme without the secure channel is proposed using the ideas of identity based systems and certificate-based encryption, which satisfies all the properties required by OSBE such as soundness and oblivious et al. Also, the scheme can achieve the desired security notations in the random oracle model.