End-to-end secure data retrieval in a dispersed storage network

• US 10,095,441 B2
• Filed: 08/16/2016
• Issued: 10/09/2018
• Est. Priority Date: 09/24/2015
• Status: Expired due to Fees

• Current Assignee: Pure Storage, Inc.
• Original Assignee: International Business Machines Corporation
• Inventors: Dhuse, Greg R., Resch, Jason K., Vossberg, Trevor J.
• Primary Examiner(s): LAMARRE, GUY J
• Application Number:
  US15/237,874
• Publication Number:
  US 20170091031A1
• Time in Patent Office: 784 Days
• CPC Class Codes: G06F 11/1092 Rebuilding, e.g. when physically replacing a failing disk
• CPC Class Codes: G06F 3/0611 in relation to response time
• CPC Class Codes: G06F 3/0614 Improving the reliability of storage systems
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0653 Monitoring storage devices or systems
• CPC Class Codes: G06F 3/0659 Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/0661 Format or protocol conversion arrangements
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 8/65 Updates security arrangements therefor G06F21/57
• CPC Class Codes: H03M 13/1515 Reed-Solomon codes
• CPC Class Codes: H03M 13/154 Error and erasure correction, e.g. by using the error and erasure locator or Forney polynomial
• CPC Class Codes: H03M 13/3761 using code combining, i.e. using combining of codeword portions which may have been transmitted separately, e.g. Digital Fountain codes, Raptor codes or Luby Transform [LT] codes
• CPC Class Codes: H04L 63/061 for key exchange, e.g. in peer-to-peer networks cryptographic mechanisms or cryptographic arrangements for key agreement H04L9/0838
• CPC Class Codes: H04L 67/01 Protocols
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• CPC Class Codes: H04L 67/06 specially adapted for file transfer, e.g. file transfer protocol [FTP]
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: H04L 67/34 involving the movement of software or configuration parameters network booting or remote initial program loading [RIPL] G06F9/4416
• CPC Class Codes: H04L 67/60 Scheduling or organising the servicing of application requests, e.g. requests for application data transmissions using the analysis and optimisation of the required network resources admission control or resource allocation H04L47/70

Abstract

A method includes a first computing device retrieving a decode threshold number of encrypted encoded data slices. The method further includes the first computing device generating a decoding matrix based on pillar numbers of the decode threshold number of encrypted encoded data slices and an encoding matrix. The method further includes the first computing device dispersed storage error decoding the decode threshold number of encrypted encoded data slices based on the decoding matrix to produce an encrypted data segment. The method further includes the first computing device sending the encrypted data segment and the pillar numbers to a second computing device. The method further includes the second computing device identifying a particular subset of encryption keys of the set of encryption keys based on the pillar numbers. The method further includes the second computing device decrypting the encrypted data segment based on the particular subset of encryption keys.

Claims

1. A method for secure data retrieval in a dispersed storage network (DSN), the method comprises:

retrieving, by an interface of a first computing device of the DSN, a decode threshold number of encrypted encoded data slices of a set of encrypted encoded data slices from at least some storage units of a set storage units of the DSN, wherein the set of storage units encrypt a set of encoded data slices using a set of encryption keys to produce the set of encrypted encoded data slices, and wherein a first encoded data slice of the set of encoded data slices is encrypted based on a first encryption key of the set of encryption keys to produce a first encrypted encoded data slice of the set of encrypted encoded data slices;

generating, by the first computing device, a decoding matrix based on pillar numbers of the decode threshold number of encrypted encoded data slices and an encoding matrix;

dispersed storage error decoding, by the first computing device, the decode threshold number of encrypted encoded data slices based on the decoding matrix to produce an encrypted data segment;

sending, by the interface of the first computing device, the encrypted data segment and the pillar numbers to a second computing device of the DSN;

identifying, by the second computing device, a particular subset of encryption keys of the set of encryption keys based on the pillar numbers; and

decrypting, by the second computing device, the encrypted data segment based on the particular subset of encryption keys.

2. The method of claim 1, wherein the retrieving the decode threshold number of encrypted encoded data slices comprises:

receiving, by the first computing device, a data retrieval request for the set of encoded data slices from the second computing device;

sending, by the first computing device, a set of data retrieval requests to the set of storage units regarding the set of encoded data slices; and

receiving, by the first computing device, the decode threshold number of encrypted encoded data slices from the at least some of the storage units.

3. The method of claim 1, wherein the generating the decoding matrix comprises:

determining the pillar numbers of encoded data slices of the decode threshold number of encrypted encoded data slices; and

reducing the encoding matrix to include rows corresponding to the pillar numbers to produce the decoding matrix.

4. The method of claim 1 further comprises:

generating a first key stream from the first encryption key; and

finite field adding the first key stream with the first encoded data slices to produce the first encrypted encoded data slice.

5. The method of claim 4, wherein the finite field adding comprises:

exclusive ORing the first key stream with the first encoded data slices to produce the first encrypted encoded data slice.

6. The method of claim 1, wherein the identifying the particular subset of encryption keys comprises:

generating the decoding matrix based on the pillar numbers; and

determining the particular subset of encryption keys based on rows of the decoding matrix.

7. The method of claim 1, wherein the decrypting the encrypted data segment based on the particular subset of encryption keys further comprises:

generating a subset of key streams from the particular subset of encryption keys;

converting the encrypted data segment into an encrypted data matrix in accordance with the decoding matrix;

a finite field adding the subset of key streams with rows of the encrypted data matrix to produce a data matrix; and

converting the data matrix into the encrypted data segment.

8. A computer readable memory comprises:

a first memory element that stores operational instructions, which, when executed by a first computing device of a dispersed storage network (DSN), causes the first computing device to;

retrieve a decode threshold number of encrypted encoded data slices of a set of encrypted encoded data slices from at least some storage units of a set storage units of the DSN, wherein the set of storage units encrypt a set of encoded data slices using a set of encryption keys to produce the set of encrypted encoded data slices, and wherein a first encoded data slice of the set of encoded data slices is encrypted based on a first encryption key of the set of encryption keys to produce a first encrypted encoded data slice of the set of encrypted encoded data slices;

generate a decoding matrix based on pillar numbers of the decode threshold number of encrypted encoded data slices and an encoding matrix;

dispersed storage error decode the decode threshold number of encrypted encoded data slices based on the decoding matrix to produce an encrypted data segment;

send the encrypted data segment and the pillar numbers to a second computing device of the DSN; and

a second memory element that stores operational instructions, which, when executed by the second computing device, causes the second computing device to;

identify a particular subset of encryption keys of the set of encryption keys based on the pillar numbers; and

decrypt the encrypted data segment based on the particular subset of encryption keys.

9. The computer readable memory of claim 8, wherein the first memory element further stores operational instructions, which, when executed by the first computing device, causes the first computing device to retrieve the decode threshold number of encrypted encoded data slices by:

receiving a data retrieval request for the set of encoded data slices from the second computing device;

sending a set of data retrieval requests to the set of storage units regarding the set of encoded data slices; and

receiving the decode threshold number of encrypted encoded data slices from the at least some of the storage units.

10. The computer readable memory of claim 8, wherein the first memory element further stores operational instructions, which, when executed by the first computing device, causes the first computing device to generate the decoding matrix by:

determining the pillar numbers of encoded data slices of the decode threshold number of encrypted encoded data slices; and

reducing the encoding matrix to include rows corresponding to the pillar numbers to produce the decoding matrix.

11. The computer readable memory of claim 8 further comprises:

a third memory element that stores operational instructions, which, when executed by a first storage unit of the set of storage units, causes the first storage unit to;

generate a first key stream from the first encryption key; and

finite field add the first key stream with the first encoded data slices to produce the first encrypted encoded data slice.

12. The computer readable memory of claim 11, wherein the third memory element further stores operational instructions, which, when executed by a first storage unit of the set of storage units, causes the first storage unit to finite field adding by:

exclusive ORing the first key stream with the first encoded data slices to produce the first encrypted encoded data slice.

13. The computer readable memory of claim 8, wherein the second memory element further stores operational instructions, which, when executed by the second computing device, causes the second computing device to identifying the particular subset of encryption keys by:

generating the decoding matrix based on the pillar numbers; and

determining the particular subset of encryption keys based on rows of the decoding matrix.

14. The computer readable memory of claim 8, wherein the second memory element further stores operational instructions, which, when executed by the second computing device, causes the second computing device to decrypt the encrypted data segment based on the particular subset of encryption keys further by:

generating a subset of key streams from the particular subset of encryption keys;

converting the encrypted data segment into an encrypted data matrix in accordance with the decoding matrix;

a

finite field adding the subset of key streams with rows of the encrypted data matrix to produce a data matrix; and

converting the data matrix into the encrypted data segment.