Key agreement method and device

Abstract

The invention discloses a key agreement method and a device. The method comprises the steps: a first user end obtains a long-term public key of a second user end conducting key agreement session with the first user end from a certificate authority; an ephemeral key of the first user end is selected randomly and the first hash calculation is conducted on the ephemeral key of the first user end and a long-term private key of the first user end to obtain a first intermediate value; according to the first intermediate value and the ephemeral key, first key agreement information is generated; after the first key agreement information is sent to the second user end, second key agreement information returned back from the second user end is received; and according to the second key agreement information, the long-term public key of the second user end, the ephemeral key of the first user end, the long-term private key of the first user end and the session identification of the key agreement session, the first user end conducts the second hash calculation to obtain a shared key. The method and the device improve the efficiency of the key agreement, and the long-term key and the ephemeral key of any party can not be simultaneously divulged, thus being capable of guaranteeing the security of agreement.

Description

Technical field [0001] The present invention relates to the technical field of secure communication, in particular to a key agreement method and device. Background technique [0002] Key agreement is a key establishment technology in which two or more participants in the system provide information together, and each derives a shared key whose results cannot be determined in advance by either party. Especially with the increasing complexity of the communication environment, the continuous development of information technology and the continuous improvement of computing power, the attack methods in the communication environment are also constantly developing, making many key agreement methods have different levels of security risks. Therefore, in modern communication , The participants in the communication should consider the security of the key agreement while ensuring the high efficiency of the key agreement. Common key agreement protocols include MQV, HMQV, NAXOS, CMQV, NETS, et...

AI Technical Summary

Problems solved by technology

The inventor found in the process of researching the existing technology that when performing key negotiation in the prior art, the two parties in the conversation need to perform multiple data exchanges to complete the key negotiation, and when one user or two parties using the protocol users When the long-term key sk is leaked at the same time, since the third party who obtains the leaked information can obtain the session key of the user in the system through calculation, the session security of the system is reduced

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