US 12,395,331 B2
Decryption key generation and recovery
Ramarathnam Venkatesan, Redmond, WA (US); and Nishanth Chandran, Bangalore (IN)
Assigned to MICROSOFT TECHNOLOGY LICENSING, LLC, Redmond, WA (US)
Filed by Microsoft Technology Licensing, LLC, Redmond, WA (US)
Filed on Sep. 13, 2022, as Appl. No. 17/931,733.
Prior Publication US 2024/0089098 A1, Mar. 14, 2024
Int. Cl. H04L 9/08 (2006.01)
CPC H04L 9/0894 (2013.01) [H04L 9/0825 (2013.01); H04L 9/085 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A system, comprising:
a processor; and
a memory that stores program code that, when executed by the processor, performs operations to recover a decryption key, the operations comprising:
receiving a cryptographic proof that a user is associated with an attribute required to access a resource in accordance with a policy;
verifying that the cryptographic proof is valid using a zero-knowledge proof;
responsive to verifying that the cryptographic proof is valid, providing a first portion of the decryption key;
determining that the user is at a location at which access to the resource is allowed in accordance with the policy;
responsive to determining that the user is at the location, providing a second portion of the decryption key; and
combining the first portion and the second portion to generate the decryption key.