US 12,393,740 B2
Methods and devices for secure access control to a data storage system and for data archiving
Hubertus Grobbel, Munich (DE)
Assigned to Swissbit AG, Bronschhofen (CH)
Filed by Swissbit AG, Bronschhofen (CH)
Filed on Dec. 14, 2022, as Appl. No. 18/065,993.
Claims priority of application No. 10 2021 133 155.2 (DE), filed on Dec. 14, 2021; and application No. 10 2022 201 339.5 (DE), filed on Feb. 9, 2022.
Prior Publication US 2023/0237205 A1, Jul. 27, 2023
Int. Cl. G06F 21/78 (2013.01); G06F 21/60 (2013.01); G06F 21/62 (2013.01)
CPC G06F 21/78 (2013.01) [G06F 21/602 (2013.01); G06F 21/6209 (2013.01)] 26 Claims
OG exemplary drawing
 
1. A method for secure access control to a data storage system for a host apparatus by-an access control device, the method comprising:
as part of a first operating mode of the access control device, receiving user data (D) from the host apparatus and transmitting of the same in unchanged or modified form (D/D′) to the data storage system for local storage;
exchanging a first cryptographic secret (K) with a computer system to enable data to be encrypted by the access control device as a function of the first cryptographic secret (K);
receiving a data read request (RR) for at least a portion of the user data stored in the data storage system;
in response to the data read request (RR), transitioning the access control device to a second mode of operation in which the access control device is configured to carry out read access but no write or delete access to the data storage system; and
in the second operating mode, retrieving user data (D/D′) requested according to the data read request (RR) from the data storage system, encrypting the user data (D/D′) using the first cryptographic secret (K) or a key derived as a function thereof in accordance with a key generation rule to produce encrypted user data (K(D/D′)) and transmitting the encrypted user data (K(D/D′)) to a predetermined user data recipient;
wherein as part of the method, the user data (D/D′) is processed in such a way that the encrypted user data (K(D/D′) transmitted as part of the second operating mode represent an information which is extractable therefrom for the user data recipient without any decryption of the encrypted user data (K(D/D′)), which information represents an identity (ID) of the access control device and/or of the data storage system or which allows a deduction of the same.