US 12,170,723 B2
Methods for splitting and recovering key, program product, storage medium, and system
Jianliang Gu, Shanghai (CN); and Bangya Ma, Shanghai (CN)
Assigned to Shanghai NanoJClean Technology, Co., Ltd., Shanghai (CN)
Appl. No. 17/593,075
Filed by Shanghai NanoJClean Technology Co., Ltd., Shanghai (CN)
PCT Filed Mar. 11, 2020, PCT No. PCT/CN2020/078801
§ 371(c)(1), (2) Date Sep. 8, 2021,
PCT Pub. No. WO2020/182151, PCT Pub. Date Sep. 17, 2020.
Claims priority of application No. 201910179156.3 (CN), filed on Mar. 11, 2019.
Prior Publication US 2022/0191012 A1, Jun. 16, 2022
Int. Cl. H04L 9/08 (2006.01); H04L 9/32 (2006.01)
CPC H04L 9/0825 (2013.01) [H04L 9/085 (2013.01); H04L 9/0869 (2013.01); H04L 9/3247 (2013.01); H04L 2209/56 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for splitting a transaction key in a key management system, wherein the key management system comprises a management device for managing user devices of users in a user group and a hardware security module connected to the management device, and the method comprises: at the hardware security module,
acquiring a number of the users of the user group and a first predetermined value, wherein the first predetermined value indicates a minimum number of users for recovering the transaction key, and the user group is configured to manage the transaction key;
randomly generating the transaction key associated with processing authority of this transaction based on messages about other users except for a splitting user determined for splitting the transaction key in the user group, wherein the messages about other users at least indicate public keys of the other users;
splitting the transaction key into a plurality of sub-keys of the same number as the number of the users, wherein each sub-key in the plurality of sub-keys corresponds to one user in the user group; and
encrypting the plurality of sub-keys respectively with public keys of the users corresponding to the plurality of sub-keys.