PROTECTION OF ENCRYPTION KEYS IN A DATABASE

• US 20100290623A1
• Filed: 05/12/2009
• Published: 11/18/2010
• Est. Priority Date: 08/17/2007
• Status: Active Grant

• Current Assignee: Sybase Incorporated (SAP SE)
• Original Assignee: Sybase Incorporated (SAP SE)
• Inventors: Banks, Barbara Jane, Chen, Shiping, Chitkara, Rajnish Kumar
• Granted Patent: US 9,158,933 B2
• Time in Patent Office: Days
• US Class Current: 380/277
• CPC Class Codes: G06F 21/6227 where protection concerns the structure of data, e.g. records, types, queries
• CPC Class Codes: H04L 9/085 Secret sharing or secret splitting, e.g. threshold schemes
• CPC Class Codes: H04L 9/0863 involving passwords or one-time passwords network architectures or network communication protocols for using one-time keys in a packet data network H04L63/067
• 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

System, method, computer program product embodiments and combinations and sub-combinations thereof for protection of encryption keys in a database are described herein. An embodiment includes a master key and a dual master key, both of which are used to encrypt encryption keys in a database. To access encrypted data, the master key and dual master key must be supplied to a database server by two separate entities, thus requiring dual control of the master and dual master keys. Furthermore, passwords for the master and dual master keys must be supplied separately and independently, thus requiring split knowledge to access the master and dual master keys. In another embodiment, a master key and a key encryption key derived from a user password is used for dual control. An embodiment also includes supplying the secrets for the master key and dual master key through server-private files.

Claims

1. A method for protecting encryption keys in a database, comprising:

(1) generating a master key, provided by a first entity;

(2) generating a dual master key, provided by a second entity; and

(3) encrypting said encryption keys using said master key and said dual master key.

2. The method of claim 1, wherein step (1) comprises:

receiving a command to create said master key;

receiving a password to protect said master key.

3. The method of claim 1, further comprising,

(4) configuring a database server associated with said database in an automatic master key access mode.

4. The method of claim 3, wherein said configuring step comprises:

enabling automatic master key access for said database server; and

creating automatic access key copies for said master key and said dual master key.

5. The method of claim 4, further comprising:

creating a key encryption key from random data;

encrypting said master key automatic access copy using said key encryption key; and

storing said key encryption key in a server-private master key startup file.

6. The method of claim 1, further comprising:

initializing a database server associated with said database in automatic master key access mode.

7. The method of claim 6, wherein said initializing step further comprises:

reading a master key copy'"'"'s key encryption key from a master key startup file;

decrypting a master key automatic access copy using said key encryption key.

8. The method of claim 1, further comprising:

altering said master key'"'"'s password.

9. The method of claim 8, wherein said altering step comprises:

receiving a first password;

receiving a second password; and

receiving a command to alter said master key,

wherein said first password is a password currently associated with said master key and said second password is a password to replace said first password.

10. The method of claim 1, further comprising:

recovering said master key and said dual master key.

11. The method of claim 1, further comprising:

regenerating said master key and said dual master key.

12. The method of claim 11, wherein said regenerating step comprises:

replacing a raw key value of said master key and said dual master key with a new raw key value; and

re-encrypting said encryption keys with regenerated master and dual master keys.

13. The method of claim 1, further comprising,

encrypting said encryption keys using a combination of said master key and a password derived key.

14. The method of claim 13, further comprising:

accessing encrypted data by providing said master key and said password derived key through different entities.

15. The method of claim 1, further comprising updating a master key startup file.

16. A database server for protecting encryption keys in a database, comprising:

a first module to generate a master key, obtained from a first entity;

a second module to generate a dual master key, obtained from a second entity; and

a third module to encrypt said encryption keys using said master key and said dual master key.

17. The system of claim 16, wherein said database server includes a key management module.

18. The system of claim 16, wherein said master key and said dual master key are database level keys.

19. The system of claim 16, wherein said master key and said dual master key are key encryption keys (KEKs) for user created keys.

20. The system of claim 16, wherein said first module uses said master key in combination with said dual master key as a composite key to provide dual control and split knowledge for all user-created keys.

21. The system of claim 16, wherein said first module uses said master key in combination with an explicit password to provide split knowledge and dual control of a user created encryption key.

22. The system of claim 16, further comprising a system table of said database, said master key being defined in said system table.

23. The system of claim 16, wherein said database server is configured in an automatic master key access mode.

24. The system of claim 23, wherein said database server creates a master key startup file for said automatic master key access mode.

25. The system of claim 24, wherein said database server reads in external MKEKs for said master and said dual master keys for all databases from said master key startup file into server memory.

26. The system of claim 24, wherein said database server creates said master key startup file as a read only file.

27. A computer program product having control logic stored therein, said control logic enabling a processor to protect encryption keys in a database, said control logic comprising:

first computer readable program code means for enabling a processor to generate a master key, provided by a first entity;

second computer readable program code means for enabling a processor to generate a dual master key, provided by a second entity; and

third computer readable program code means for enabling a processor to encrypt said encryption keys using said master key and said dual master key.