Novel secret key separated signing method and system

Abstract

The invention provides a secret key separated signing method with a self update capability of a secret key of an assisting device. The method comprises the steps that a singer generates an initial singer secret key SK0 according to two randomly selected parameters which are s0 and h0 and a password hash function H1, the assisting device will send the signer an assisting device update message SKUi at the beginning of each subsequent time slice to help the singer to update a temporary secret key SKi of a current time slice, the assisting device also carries out self update on a secret key of the assisting device in each time slice simultaneously with the operation that the assisting device helps the signer to update the temporary secret key of the signer, a parameter h0 is randomly selected in a time slice 0 to be regarded as the initial secret key HK0 of the assisting device, and the secret key of the assisting device is updated to HKi in a time slice i. The method can reduce the possibility that the secret key of the assisting device is revealed, and therefore the safety of the secret key separated signing method is enhanced greatly.

Description

technical field [0001] The present invention relates to the technical field of information security, in particular to a method and system for key isolation signature with the self-renewing capability of a facilitator key. Background technique [0002] Cryptography technology is an important basis for network security protection. Data encryption, authentication, digital signature, electronic currency, etc. are all closely related to cryptography technology. Through cryptographic algorithms, ordinary Internet users can not only protect their privacy, but also conduct reliable online transactions, online payments, and establish trust relationships on the Internet. [0003] With the development of new technologies, more and more mobile devices such as smart phones and mobile Internet devices have applied digital signature technology, but these mobile devices themselves do not have high security, making it difficult to avoid key leakage. In traditional cryptographic systems, onc...

AI Technical Summary

Problems solved by technology

[0004] The key leakage problem is a serious security problem. No matter how secure the cryptographic system is designed, as long as the key is leaked, all cryptographic operations related to this key are no longer safe.

However, this scheme does not have key isolation. If the key of the facilitator is leaked, the security of the system is difficult to be guaranteed; the system public key and the facilitator key increase linearly with the increase of the life cycle

[0008] Since the key update in the key isolation technology is completed depending on the key update message generated by the facilitator, once the key of the facilitator is leaked, the key isolation system is also insecure

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