3results about How to "Improve decryption efficiency" patented technology

The invention discloses a block chain-based lightweight message distribution mechanism for Internet of Things end equipment, CP-ABE decryption operation is unloaded to edge equipment for processing, and after the edge equipment completes ciphertext dimension reduction conversion, terminal equipment only needs to execute bilinear pairing operation and group element multiplication operation once to complete decryption. A task scheduling mechanism based on attribute cooperative authorization is designed, and distribution of ciphertext conversion tasks between edge devices is supported. According to the method, the ciphertext is encrypted by adopting CP-ABE, the identity information of the message receiver on the block chain is encrypted and hidden, and the temporary identity credential is decrypted on the edge equipment, so that correct distribution of the message is ensured, and the risk of inferring the long-term behavior privacy of the user through on-chain transaction mode analysis is prevented. A credible collaboration system is constructed based on an intelligent contract, and the traceability of a collaboration process, the compliance of node screening and the blocking of illegal equipment are guaranteed. The mechanism effectively avoids the limitation of the traditional scheme in the aspects of terminal computing load, edge expansibility, identity privacy protection and the like.

This invention relates to a fast decryption method for attribute-based encryption using a key policy based on SM9. The method includes: a key generation center first generates system public parameters and a system master private key based on given system security parameters; secondly, it defines the system's attribute space based on the attributes used in the system; finally, it publishes the system public parameters but keeps the master private key secret; the data owner encrypts the message based on the attribute set corresponding to the data, generating corresponding ciphertext; the key generation center sets an access policy based on the user's decryption permissions, where a matrix is ​​used to map rows in the matrix to attributes in the attribute set, generating a private key corresponding to the corresponding access policy; after receiving the ciphertext, the data receiver can successfully decrypt it if and only if the attribute set in the ciphertext satisfies the access policy on the key; otherwise, decryption fails. This invention overcomes the decryption efficiency problem in attribute-based encryption algorithms using a key policy based on SM9.

Embodiments of the present disclosure provide a decryption method, a variable storage method, and related devices, equipment, media and products. The decryption method monitors the current signal of the chip through the current probe, monitors the electromagnetic signal of the SRAM through the electromagnetic probe, determines the key bit value corresponding to the coordinate value stored in the SRAM based on the signal change mode of the current signal and the electromagnetic signal, and then obtains the decryption result. Through the current-electromagnetic dual-channel acquisition and analysis scheme, the ability to obtain effective information in the decryption process is improved, the redundant information processing process is reduced, and the password cracking efficiency is improved. The variable storage method stores the coordinate values of at least two coordinate dimensions of at least one password intermediate variable in at least two SRAMs, or stores the coordinate values of at least one coordinate dimension of at least two password intermediate variables in the same SRAM, which can avoid local electromagnetic radiation analysis and the storage process does not affect the execution efficiency of the encryption algorithm.