US 12,362,920 B2
Threshold secret sharing with hidden access structures
Foo Yee Yeo, Shugart (SG)
Assigned to SEAGATE TECHNOLOGY LLC, Fremont, CA (US)
Filed by Seagate Technology LLC, Fremont, CA (US)
Filed on May 19, 2022, as Appl. No. 17/748,900.
Prior Publication US 2023/0379144 A1, Nov. 23, 2023
Int. Cl. H04L 9/08 (2006.01)
CPC H04L 9/085 (2013.01) 20 Claims
OG exemplary drawing
 
1. A computing-processor-implemented method of cryptographically sharing a cryptographic secret among multiple parties, the method comprising:
generating a share of the cryptographic secret for each party of the multiple parties;
generating a set of multiple threshold access structure tokens for each party of the multiple parties, the multiple threshold access structure tokens being generated for a party from one or more random token polynomials selected from a finite field based on a number of the multiple parties capable of attempting to reconstruct the cryptographic secret; and
distributing the shares of the cryptographic secret and the sets of the multiple threshold access structure tokens to the multiple parties, each party receiving a different share of the cryptographic secret and a different set of the multiple threshold access structure tokens, wherein at least a threshold number of the parties can reconstruct the cryptographic secret using the shares of the cryptographic secret and the multiple threshold access structure tokens corresponding to at least a threshold number of the parties attempting to reconstruct the cryptographic secret and less than the threshold number of the parties cannot reconstruct the cryptographic secret using the shares of the cryptographic secret and the multiple threshold access structure tokens corresponding to the less than the threshold number of the parties.