New proof of confidentiality and originality of data in strand space
Jiang Shao-hui · Journal of Guangxi University · 2009
The ideal and its corollaries in strand space model greatly simplify the analysis of security protocols.But the existing theorems are only adaptive to the security protocols based on symmetric key,they,however,can't be used to analyze the security protocols based on asymmetric key,so it is very tedious to analyze security protocols based on asymmetric key with the original strand space theorems.To analyze the security protocols based on symmetric as well as asymmetric key,the theorems of data confidentiality and the origin of confidential data are proposed,which can be used to analyze the security protocols based on symmetric and asymmetric key.First,the original strand space is extended,substrand and a group of confidential data substrands of regular strand are defined,and the theorem of data confidentiality is redefined,in the definition of data confidentiality theorem,the confidentiality of private key is added,and the theorem of data confidentiality is reproved completely from the aspect of regular strands and intruder strands.After that,with the theorem of data confidentiality,the theorem of origin of confidential data is proposed for the first time,which proves the unique origin of the confidential data.Since both theorems take the security protocols based on symmetric and asymmetric key into account,they can be applied to analyze security protocols based on symmetric key and asymmetric key.Compared to the original strand space,these two theorems can simplify the analysis of security protocols greatly and improve the efficiency of analysis.Finally,the theorems of data confidentiality and origin of confidential data are utilized to reanalyze NSPK protocol,the reason why the attack exists is explained.