Decentralized remotely encrypted file system

• US 6,405,315 B1
• Filed: 09/11/1997
• Issued: 06/11/2002
• Est. Priority Date: 09/11/1997
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Reed, Benjamin Clay, Long, Darrell, Chron, Edward Gustav, Burns, Randal Chilton
• Primary Examiner(s): Hayes, Gail
• Assistant Examiner(s): DI LORENZO, ANTHONY
• Application Number:
  US08/927,772
• Time in Patent Office: 1,734 Days
• Field of Search: 380/21, 380/49, 380/3, 380/4, 713/201, 713/190, 713/193
• US Class Current: 713/190
• CPC Class Codes: G06F 16/10 File systems; File servers
• CPC Class Codes: G06F 21/6218 to a system of files or objects, e.g. local or distributed file system or database
• CPC Class Codes: G06F 2211/007 Encryption, En-/decode, En-/decipher, En-/decypher, Scramble, (De-)compress

Abstract

A decentralized file system based on a network of remotely encrypted storage devices is disclosed. The file system includes a network to which a network client, a secure remotely encrypted storage device, a key manager, and a lock manager are attached. The system organizes data as files and directories. Files or directories are composed of one or more streams, which logically partition the data associated with the files or directories. The device serves as a repository of the system'"'"'s data. The key manager controls data access keys while the lock manager handles consistency of the files. A network user may have read or write access to a file. Access is controlled using keys and access lists maintained by the key manager.

Claims

1. A distributed file system for use with a network of storage devices, each device having means for storing data as remotely encrypted data objects including encrypted metadata describing a directory structure in said distributed file system, means for authenticating data requests and responses, and means for determining freshness of the requests, the system comprising:

at least one client that each performs file management tasks and can remotely encrypt and decrypt the data objects using a plurality of keys;

a key manager for controlling the keys used by the client to access the data objects; and

a lock manager for maintaining data consistency when the client accesses the data objects, wherein files and metadata may be copied directly from one storage device to another storage device in a secure manner, and only said clients possessing appropriate encryption and decryption keys have access to data stored in said storage devices.

2. The distributed file system of claim 1, wherein said storage devices replace old stored data with new data upon request of said client.

3. The distributed file system of claim 1, wherein said file management tasks include maintaining a logical mapping of locations of files and directory entries stored on said network of storage devices.

4. The distributed file system of claim 3, wherein said files and directory entries comprise one or more streams logically partitioning data into said data objects.

5. The distributed file system of claim 4, wherein each said directory entry is stored as a set of stream stripe sets each referring to a group of directory data objects on said storage devices, with each directory data object containing an encrypted parent reference, file metadata, and encrypted stream locations in terms of byte ranges on said storage devices.

6. The distributed file system of claim 5, wherein if said directory entry refers to another directory then the stream locations are given as another stream stripe set of the same structure, and if said directory entry refers to a file then each stream stripe set corresponds to a group of file data objects on said storage devices and includes several stripes each representing a given range of bytes of the stream on one or more of said storage devices.

7. The distributed file system of claim 6, wherein each of said stripes includes a list of associated file data objects, a stride describing the number of bytes written to a particular network object before moving to a next network object, and a chunk size describing the number of bytes subject to encryption at a time.

8. The distributed file system of claim 7, wherein each chunk includes a combination of file data together with a hash of the data, with the combination then encrypted with an encryption key associated with the stream stripe set.

9. A method for storing data as remotely encrypted data objects on a network of storage devices in a distributed file system, comprising the steps of:

requesting data from said storage devices using at least one client;

authenticating data requests and responses using a plurality of keys, controlling said keys using a key manager;

accessing data using at least one client to perform file management tasks; and

maintaining data consistency using a lock manager,

wherein files and metadata may be copied directly from one storage device to another storage device in a secure manner, and only said clients possessing appropriate encryption and decryption keys have access to data stored in said storage devices, and said remotely encrypted data objects include encrypted metadata describing a directory structure in said distributed file system.

10. The method of claim 9, wherein said storage devices replace old stored data with new data upon request of said client.

11. The method of claim 9, wherein said file management tasks include maintaining a logical mapping of locations of files and directory entries stored on said network of storage devices.

12. The method of claim 11, wherein said files and directory entries comprise one or more streams logically partitioning data into said data objects.

13. The method of claim 12, wherein each said directory entry is stored as a set of stream stripe sets each referring to a group of directory data objects on said storage devices, with each directory data object containing an encrypted parent reference, file metadata, and encrypted stream locations in terms of byte ranges on said storage devices.

14. The method of claim 13, wherein if said directory entry refers to another directory then the stream locations are given as another stream stripe set of the same structure, and if said directory entry refers to a file then each stream stripe set corresponds to a group of file data objects on said storage devices and includes several stripes each representing a given range of bytes of the stream on one or more of said storage devices.

15. The method of claim 14, wherein each of said stripes includes a list of associated file data objects, a stride describing the number of bytes written to a particular network object before moving to a next network object, and a chunk size describing the number of bytes subject to encryption at a time.

16. The method of claim 15, wherein each chunk includes a combination of file data together with a hash of the data, with the combination then encrypted with an encryption key associated with the stream stripe set.