Method and system for backing up private key of electronic signature token

A system for backing up a private key of an electronic signature token, comprising a first electronic signature token and a second electronic signature token, wherein the first electronic signature token comprises a first sending module, a second verification module, a second determining module and a decrypting module, the second electronic signature token comprises a first verification module, a first determining module, an encrypting module and a second sending module,

• the first sending module is configured to send a private key backup request data packet, in which the private key request data packet comprises a first signature, and the first signature is obtained by signing at least a first indication information using a CA private key, the first indication information recording a primary-backup relationship of the first electronic signature token;
• the first verification module is configured to verify the first signature in the private key backup request data packet after receiving the private key backup request data packet;
• the first determining module is configured to determine according to the first indication information whether the first electronic signature token has a primary-backup relationship with the second electronic signature token, if the first signature passes verification;
• the encrypting module is configured to, encrypt a private key of the second electronic signature token to obtain an encrypted private key of the second electronic signature token if the first electronic signature token has a primary-backup relationship with the second electronic signature token;
• the second sending module is configured to send a private key backup response data packet, in which the private key backup response data packet comprises a second signature and the encrypted private key of the second electronic signature token, and the second signature is obtained by signing at least a second indication information using the CA private key, the second indication information recording a primary-backup relationship of the second electronic signature token;
• the second verification module is configured to verify the second signature in the private key backup response data packet after receiving the private key backup response data packet;
• the second determining module is configured to determine according to the second indication information whether the second electronic signature token has the primary-backup relationship with the first electronic signature token, if the second signature passes the verification;
• and
• the decrypting module is configured to decrypt the encrypted private key of the second electronic signature token in the private key backup response data packet to obtain the private key of the second electronic signature token, if the second electronic signature token has the primary-backup relationship with the first electronic signature token.