Methods and devices for protecting sensitive data of transaction activity based on smart contract in blockchain

A device for creating an account for a transaction activity in a blockchain system, the device comprising:

• one or more processors;
• and
• one or more computer-readable memories coupled to the one or more processors and having instructions stored thereon that are executable by the one or more processors, wherein the one or more processors are configured to:
• receive activity data for creating an account for the transaction activity from a user, wherein the activity data include at least an identifier of a smart contract in a blockchain and an expiration time of the transaction activity, and the smart contract includes computer-readable instructions for conducting the transaction activity;
• send the activity data to an authentication server for requesting a digital certificate of the activity data, wherein the digital certificate stores the identifier of the smart contract, and an expiration time of the digital certificate is set to be the expiration time of the transaction activity;
• receive the digital certificate from the authentication server, and cause the blockchain system to perform:
• determining whether the digital certificate is valid using a public key associated with the authentication server;
• and
• creating the account for the transaction activity based on a determination that the digital certificate is valid, wherein the created account is associated with the identifier of the smart contract;
• receive, from the blockchain system, an identifier of the account for the transaction activity;
• and
• send an indication that the account has been created to the user.

A non-transitory computer-readable medium having stored therein instructions that, when executed by a processor of a device, cause the device to perform a method for creating an account for a transaction activity in a blockchain system, the method comprising:

• receiving activity data for creating an account for the transaction activity from a user, wherein the activity data include at least an identifier of a smart contract in a blockchain and an expiration time of the transaction activity, and the smart contract includes computer-readable instructions for conducting the transaction activity;
• sending the activity data to an authentication server for requesting a digital certificate of the activity data, wherein the digital certificate stores the identifier of the smart contract, and an expiration time of the digital certificate is set to be the expiration time of the transaction activity;
• receiving the digital certificate from the authentication server, and causing the blockchain system to perform:
• determining whether the digital certificate is valid using a public key associated with the authentication server;
• and
• creating the account for the transaction activity based on a determination that the digital certificate is valid, wherein the created account is associated with the identifier of the smart contract;
• receiving, from the blockchain system, an identifier of the account for the transaction activity;
• and
• sending an indication that the account has been created to the user.