Crypto-erasure resilient to network outage

• US 10,205,594 B1
• Filed: 03/30/2016
• Issued: 02/12/2019
• Est. Priority Date: 03/30/2016
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Inventors: Kaufman, Charles W.
• Primary Examiner(s): Su, Sarah
• Application Number:
  US15/085,890
• Time in Patent Office: 1,049 Days
• CPC Class Codes: H04L 9/0822 using key encryption key
• CPC Class Codes: H04L 9/083 involving central third party, e.g. key distribution center [KDC] or trusted third party [TTP]
• CPC Class Codes: H04L 9/0891 Revocation or update of secret information, e.g. encryption key update or rekeying
• CPC Class Codes: H04L 9/0894 Escrow, recovery or storing of secret information, e.g. secret key escrow or cryptographic key storage

Abstract

Examples are generally directed towards providing a server polling component for remote cryptographic key erasure resilient to network outage. A set of keys received from a server are stored on data storage. The data storage sends a status request to the server. If a key enabled status is received, the data storage continues normal operations. If a key disabled status is received, a key failure action is performed. The key failure action includes deleting one or more of the keys in the set of keys or shutting down one or more storage devices of the data storage. If no response is received from the server, the data storage iteratively resends the status request at retry time intervals until a response is received from the server or until a time out period expires. On expiration of the time out period, the key failure action is performed.

Claims

1. A computer-implemented method executed by one or more processors, the method comprising:

receiving, at the one or more processors over a network, a local copy of a set of keys from an external key server located remotely from a data storage;

initiating utilization of the local copy of the set of keys for one or more of encrypting data and decrypting data, the local copy of the set of keys comprising at least one cryptographic key associated with encrypted data stored on the data storage;

storing the local copy of the set of keys in a memory of the data storage;

on occurrence of a polling time interval, sending, over the network by the one or more processors executing a server polling component, a status request to the external key server requesting a status of the set of keys stored on the external key server;

on determining a key available response to the status request is received from the external key server at the one or more processors over the network, continuing the utilization of the local copy of the set of keys, the key available response indicating an enabled status of the set of keys stored on the external key server; and

on determining a key unavailable response to the status request is received from the external key server at the one or more processors over the network, performing a key failure action to prevent the continued utilization of the local copy of the set of keys, the key unavailable response indicating at least one key in the set of keys stored on the external key server is disabled.

2. The computer-implemented method of claim 1 wherein the status request is a first status request and further comprising:

on determining a response wait time has passed without receiving a response to the first status request from the key server, sending a second status request to the key server;

on determining the response wait time has passed without receiving a response to the second status request from the key server, sending a third status request to the key server.

3. The computer-implemented method of claim 2, wherein the server polling component iteratively sends status requests to the key server at retry time intervals until a maximum number of status request retry attempts is reached, and further comprising:

on determining the maximum number of retry attempts have been made without receiving a response from the key server, performing the key failure action, wherein the maximum number of retry attempts is a threshold number of status requests the data storage sends to the key server at the retry time intervals without receiving a response to the status requests prior to performing the key failure action.

4. The computer-implemented method of claim 1, wherein the server polling component iteratively sends another status request to the key server at retry time intervals until a response is received from the key server or a time out period is reached, and further comprising:

on occurrence of the time out period without receiving a response from the key server, performing the key failure action, wherein the time out period is a maximum length of time for sending status requests to the key server at the retry time intervals without receiving a response to the status requests from the key server.

5. The computer-implemented method of claim 1 wherein performing the key failure action further comprises:

deleting the at least one key from the memory.

6. The computer-implemented method of claim 1, wherein performing the key failure action further comprises:

rebooting the data storage.

7. The computer-implemented method of claim 1, wherein performing the key failure action further comprises:

disabling at least one data storage device associated with the data storage.

8. The computer-implemented method of claim 1, wherein performing the key failure action further comprises:

sending a notification of initiation of the key failure action to at least one user.

9. The computer-implemented method of claim 1, wherein the key server is a first key server, and further comprising:

on occurrence of the polling time event, sending the status request to a set of key servers, the set of key servers comprising the first key server and a second key server, the first key server located remotely to the second key server;

on determining a key available response to the status request is received from both the first key server and the second key server, continuing utilization of the set of keys; and

on determining a key unavailable response to the status request is received from at least one key server in the set of key servers, performing a key failure action, the key failure action preventing continued utilization of the at least one key in the set of keys.